Attenuation of waiting time mortality with heterotopic heart transplantation. As the number of heart transplants and the number of transplant programs has increased, so has the waiting time for a suitable organ. To more accurately assess the magnitude of this increase and the influence of recipient size, we reviewed waiting times for large (body surface area greater than or equal to 1.95 m2) and small (body surface area less than 1.95 m2) patients with respect to era of transplantation. Patients who underwent transplantation early (1984 to December 31, 1986) waited 35 +/- 47 days (mean +/- standard deviation), whereas patients who underwent transplantation in the late era (1987 to September 30, 1989) waited 83 +/- 102 days (p = 0.001). Large patients waited longer (130 +/- 142 days) in the late era than did small patients (60 +/- 67 days; p = 0.008). During the heterotopic era (October 1, 1989 to June 30, 1990), waiting times for large patients who received a heterotopic transplant (67 +/- 46 days) were significantly shorter than those for patients who received an orthotopic transplant (166 +/- 157 days; p = 0.05). Waiting times for small patients remained unchanged. In addition, waiting time mortality decreased from 24% to 9% (p less than 0.05). Comparison of orthotopic and heterotopic procedures performed during the same era revealed no significant differences in recipient age, preoperative status, graft ischemic time, donor age, early and midterm survival, or early postoperative functional status. Heterotopic heart transplantation may effectively increase the size of the donor pool, decrease the waiting time, and decrease waiting time mortality without increasing the morbidity of the procedure.


Cardiac valve replacement in patients infected with the human immunodeficiency virus. Major surgical procedures, especially when performed under general anesthesia, can depress immunological parameters measured in vitro. Therefore concern has been expressed that operation might have an adverse effect on the immune status of individuals infected with the human immunodeficiency virus (HIV). Four HIV-positive patients without symptoms of HIV disease underwent cardiac valve replacement in consequence of infective endocarditis. After up to 15 months postoperatively, 3 patients are alive and well without signs of progressive immunodeficiency or recurrent endocarditis. One patient died of recurrent endocarditis without evidence of HIV-related disease on autopsy. Cardiac operation does not seem to accelerate HIV-related immunodeficiency.


Repair of aortico-left ventricular tunnel associated with subpulmonary obstruction. Aortico-left ventricular tunnel is a rare congenital cardiac defect. Because the tunnel traverses the upper portion of the interventricular septum, the potential exists for an aneurysmal tunnel to obstruct the outflow of the right ventricle. We report our clinical experience with such a patient, and emphasize the importance of a two-patch technique to avoid its occurrence.


Mediastinal window: a cause of simultaneous bilateral spontaneous pneumothorax. A case of bilateral spontaneous pneumothorax with critical collapse of both lungs in a previously healthy 19-year-old woman is described. A congenital defect of mediastinal septum was suspected on the basis of roentgenographic findings and confirmed by right-sided thoracotomy. This mediastinal window between the pleural spaces allowed air leaking from a ruptured right lung apical bulla to collapse not only the right lung but also the left. Apical TA stapler resection and right-sided parietal pleurectomy was performed to prevent recurrence.


Intraoperative echocardiographic diagnosis of previously unrecognized cor triatriatum. Cor triatriatum is a congenital heart defect resulting in abnormal septation of the left atrium by a fibromuscular membrane. Echocardiography has improved the preoperative diagnosis of this rare congenital heart defect. We report a case where transesophageal echocardiography proved useful in the intraoperative diagnosis of a previously undetected cor triatriatum.


Anastomotic ulcer-induced aortoenteric fistula after esophagogastroplasty. A 67-year-old woman underwent an esophagogastrectomy and esophagogastrostomy for carcinoma of the distal esophagus. She died of massive hematemesis and exsanguination on the 14th postoperative day. An acute peptic ulcer-induced aortoenteric fistula was present at the anastomotic line. The literature on peptic ulcer-induced aortoenteric fistulas after esophagogastroplasty is reviewed.


Retrograde cerebral perfusion with circulatory arrest in aortic arch aneurysms. Two surgical cases of aortic arch aneurysms are presented. Retrograde (venoarterial) cerebral perfusion during circulatory arrest under deep hypothermia was performed to evacuate air and debris in cerebral vessels and preserve cerebral tissue. On postoperative day 1, the patients were conscious and alert with no neurological deficit. This technique is simple and can be applied during standard cardiopulmonary bypass. The technique is useful to avoid cerebral air and thromboembolisms.


Pericardioperitoneal shunt for persistent pericardial effusions: a new drainage procedure. We report a pericardioperitoneal shunt procedure in 2 patients with persistent pericardial effusions in which the classic surgical methods of shunting were inappropriate.


Coronary artery bypass grafting nine years after cardiac transplantation. Angina and increasing exertional dyspnea developed in a 53-year-old man 9 years after cardiac transplantation. Left heart catheterization revealed severe proximal triple coronary artery disease, and he underwent surgical revascularization. Now 18 months after the operation he continues to be free of symptoms.


Systemic atrioventricular valve replacement in an infant with corrected transposition of the great arteries. A 3-month-old infant with corrected transposition of the great arteries and severe systemic atrioventricular valve regurgitation due to "Ebstein-like anomaly" is reported. Through a right thoracotomy and longitudinal left atrial incision, a 19-mm St. Jude Medical valve was implanted into the annulus without removing the native valve. He is doing well 7 months after operation.


Videothoracoscopic enucleation of esophageal leiomyoma. A new thoracoscopic technique to enucleate esophageal leiomyomas is described. The procedure has been successfully performed in 3 patients. All patients benefited by this new surgical approach due to the decreased operative trauma, reduced postoperative pain, quick recovery, and minute skin scars. Although further clinical experience and longer periods of follow-up are needed to evaluate the full benefits and limits of this new access, the early results of the thoracoscopic approach are promising.


Placement of an endotracheal tube in the short tracheal stump. Placement of an endotracheal tube in the short tracheal stump, such as after a mediastinal tracheostomy, can be a difficult task. The tube may easily slide into the right main bronchus or slip out of the trachea completely. We have described a method for securing such an airway for ventilation during general anesthesia.


Simple method to monitor pulmonary artery pressure in infants after cardiac operations. Intraoperative placement of catheters to monitor pulmonary artery pressure and cardiac output by oximetry can easily be accomplished under direct vision. The insertion through a saphenous vein cutdown assures a much safer removal, eliminating the risk of bleeding, tamponade, and catheter entrapment.


Management of aortic cannulation site blowouts. An alternative technique of handling the aortic cannulation site blowout is described. The cannulation site is excluded with a side-biting clamp. The area is excised. Pericardial patch is sewn in to cover the defect.


Pericardioplasty.

Pericardioplasty. When so desired, a simple technique can be performed to close the pericardium after a cardiac operation. The only requirement is to think about it during the opening of the pericardium and make the appropriate cuts.


Current concepts concerning the nature and treatment of Barrett's esophagus and its complications. Current concepts regarding the nature and the treatment of Barrett's esophagus and its complications are reviewed. The columnar-lined lower esophagus is being increasingly recognized as an acquired condition caused by gastroesophageal reflux. Many patients are asymptomatic. Barrett's esophagus occurs in about 10% to 15% of patients with reflux esophagitis. The diagnosis depends on endoscopy and biopsy. Complications are common and include ulceration, stricture, dysplasia, and adenocarcinoma. Esophagitis, ulceration, and stricture can usually be treated medically. Surgical approaches are discussed for patients whose condition is refractory to medical therapy. The premalignant nature of Barrett's epithelium is well recognized, and strategies for surveillance and resection are discussed. Survival after resection of adenocarcinoma in Barrett's esophagus is not appreciably different from that of other carcinomas. Surveillance with endoscopy offers the best chance for early detection and cure.


Projections from cortical visual areas of the superior temporal sulcus to the superior colliculus, in macaque monkeys. 1. The distribution of tectal projections of two visual areas of the superior temporal sulcus (MT and MST areas) has been studied, in five Macaca fascicularis, by means of the autoradiographic method tracing the anterograde transport of tritiated aminoacids intracortically injected. 2. In all cases the ipsilateral superior colliculi (SC) were found labelled, whereas the contralateral ones were devoid of label. 3. The three brains injected in the MT area resulted in SC labels that involved the superficial gray layer (SGS), the stratum opticum (SO) and the intermediate gray layer (SGI), sparing the layers below SGI. 4. The collicular labels found after injections within the MST area exhibited their distribution over the deep SC subdivision, whereas they spared all the superficial layers but the deep part of the SO. 5. In two animals with large uptake zones, one in MT and the other in MST, the labelling within the SGI showed a cluster-like pattern. 6. The distinct found bulk of projections of MT and MST respectively to the superficial and deep subdivisions of the SC, along with a number of peculiar connections of the MST area as mentioned in the text, contribute to depict an overall neural network in which MST appears to be more strongly involved than MT in linking sensory visual with oculomotor attentive functions.


Activity of cat cerebellar neurons in penicillin epilepsy and amphetamine treatment. The discharge pattern of cerebellar Purkinje cells and fastigial neurons was studied after acute amphetamine treatment in immobilized cats, as well as during generalized penicillin-induced epilepsy. There was a marked reversible decrease in spontaneous firing rate of Purkinje cells and an increase in spontaneous firing rate of fastigial neurons after acute d-1 amphetamine administration (5 mg/kg, s.c.). The discharge pattern of Purkinje cells showed tendency towards inhibition, while the fastigial neurons showed less clear tendency towards disinhibition in the course of epilepsy induced by parenteral administration of penicillin (400.000-500.000 I.U./kg, i.m.). Moreover, acute amphetamine treatment (5 mg/kg, s.c.) performed after the development of penicillin-induced epileptic episodes elicited a prominent suppression of Purkinje cell discharges associated with a parallel increase in discharges of fastigial neurons. These results suggest that the changes in discharge rate of cerebellar corticonuclear neurons induced by amphetamine contribute to suppression of seizural activity in the feline model of generalized epilepsy.


Single unit activity in the guinea-pig cochlear nucleus during sleep and wakefulness. The effects of waking and sleep on the response properties of auditory units in the ventral cochlear nucleus (CN) were explored by using extracellular recordings in chronic guinea-pigs. Significant increases and decreases in firing rate were detected in two neuronal groups, a) the "sound-responding" and b) the "spontaneous" (units that do not show responses to any acoustic stimuli controlled by the experimenter). The "spontaneous" may be considered as belonging to the auditory system because the corresponding units showed a suppression of their discharge when the receptor was destroyed. The auditory CN units were characterized by their PSTH in response to tones at their characteristic frequency and also by the changes in firing rate and probability of discharge evaluated during periods of waking, slow wave and paradoxical sleep. The CNS performs functions dependent on sensory inputs during wakefulness and sleep phases. By studying the auditory input at the level of the ventral CN with constant sound stimuli, it was shown that, in addition to the firing rate shifts, some units presented changes in the temporal probability of discharge, implying central actions on the corresponding neurons. The mean latency of the responses, however, did not show significant changes throughout the sleep-waking cycle. The auditory efferent pathways are postulated to modulate the auditory input at CN level during different animal states. The probability of firing and the changes in the temporal pattern, as shown by the PSTH, are thus dependent on both the auditory input and the functional brain state related to the sleep-waking cycle.


Electrophysiological relations between the superior colliculus and the red nucleus in the cat. The electrical activity of single units located in the parvicellular part of the red nucleus (pRP) was recorded extracellularly in nitrous oxide anesthetized and C1-transected adult cats. In this area, neurons were found to respond to electrical stimulation applied to intermediate and deep layers of the right superior colliculus (SC). Forty neurons located in the pRN of both sides were studied. Three neurons out of 18 (16.6%) located in the contralateral pRN and six neurons out of 22 (27.3%) located in the ipsilateral pRN were driven by the right SC stimulation. The pRN neurons were separated into four groups according to the latency response to the SC stimulation: 1) 0.6-1.9 ms, 2) 2-4 ms, 3) 4-6 ms, 4) variable latency responses. Each of these four groups of neurons showed a particular pattern of discharge, even though their discharge frequency showed a strong consistency. Four pRN neurons, which responded to SC stimulation, showed a significant correlation with spontaneous horizontal eye movements of saccadic type. It is known that the SC represents one of the main outputs of the striato-nigral motor system. The relation between the SC and the pRN described in the present study suggest that connections exist between the cortico-rubral and the striato-nigral systems, since both have the SC as a common output structure. It is likely, therefore, that the cortico-rubral-SC system is involved in the control of oculomotor functions, and that the SC may serve to establish interactions between systems concerned with eye movements.


Utilization of methoxylated benzoates and formation of intermediates by Desulfotomaculum thermobenzoicum in the presence or absence of sulfate. Desulfotomaculum thermobenzoicum strain TSB (DSM 6193) was found to utilize some methoxylated benzoates as carbon and energy source with or without sulfate. 3- or 4-Methoxybenzoate, vanillate (4-hydroxy-3-methoxybenzoate), syringate (3,5-dimethoxy-4-hydroxybenzoate) and 3,4,5-trimethoxybenzoate were converted to corresponding hydroxybenzoates. However, neither 2-methoxybenzoate nor 2,6-dimethoxybenzoate was utilized. The organism grew acetogenically on each of the methoxylated benzoates in the absence of sulfate. 3,4-Dihydroxy-5-methoxybenzoate was detected during conversion of syringate, and syringate and 3,4-dihydroxy-5-methoxybenzoate were detected during conversion of 3,4,5-trimethoxybenzoate as intermediates. These findings indicate that 4-methoxyl-group is most readily cleaved, whereas 2-methoxyl-group is not utilized by the organism.


Thiobacillus plumbophilus spec. nov., a novel galena and hydrogen oxidizer. From an uranium mine three strains of rod-shaped, mesophilic, chemolithouautotrophic bacteria were isolated. They grow by oxidation of H2S, galena (PbS) and H2. Angelsite (PbSO4) is formed from galena. No ferrous iron is oxidized by the isolates. They grow between pH 4 and 6.5 at temperatures of about 9 to 41 degrees C (optimum around 27 degrees C). The G + C content of the DNA is around 66 mol %. Based on their ability to oxidize sulfur compounds, the new organisms belong to the genus Thiobacillus. No significant homology with Thiobacillus ferrooxidans and Thiobacillus cuprinus was detected by DNA-DNA hybridization. Therefore the new isolates represent a new species within the genus Thiobacillus. Based on the unusual growth on galena, we name the new species Thiobacillus plumbophilus (type strain Gro7; DSM 6690).


Periplasmic location of nitrous oxide reductase and its apoform in denitrifying Pseudomonas stutzeri. Immunogold labelling techniques on ultrathin sections of low temperature embedded cells yielded evidence for the periplasmic location of the respiratory enzymes N2O reductase and nitrite reductase (cytochrome cd1) in Pseudomonas stutzeri strain ZoBell. Cell fractionation by spheroplast preparation and two-dimensional electrophoresis showed the absence of a membrane association of these enzymes. Immunocytochemical localization of N2O reductase in a mutant strain deficient in the chromophore of N2O reductase showed the gold label at the cell periphery, indicating that the copper chromophore processing takes place after export of this protein's apoform.


Synthesis in vitro of very long chain fatty acids in Vibrio sp. strain ABE-1. The activity of fatty acid synthetase (FAS) from Vibrio sp. strain ABE-1 required the presence of acyl carrier protein and was completely inhibited by thiolactomycin, an inhibitor specific for a type II FAS. These observations indicate that this enzyme is a type II FAS. Analysis by gas-liquid chromatography of the reaction products synthesized in vitro from [2-14C]malonyl-CoA by the partially purified FAS revealed, in addition to 16- and 18-carbon fatty acids which are normal constituents of this bacterium, the presence of fatty acids with very long chains. These fatty acids were identified as saturated and mono-unsaturated fatty acids with 20 up to as many as 30 carbon atoms. The longest fatty acids normally found in this bacterium contain 18-carbon atoms. These results suggest that the FAS from Vibrio sp. strain ABE-1 has potentially the ability to synthesize fatty acids with very long chains.


Gas vesicles are strengthened by the outer-surface protein, GvpC. The critical collapse pressure of gas vesicles isolated from Anabaena flos-aquae decreased from 0.557 to 0.190 MPa when GvpC, the hydrophilic 22 kDa protein present on the outer surface of the gas vesicle, was removed by rising in 6 M urea. Recombinant GvpC was purified from inclusion bodies, produced in an E. coli strain containing an expression vector bearing the gene encoding GvpC from A. flos-aquae, and then solubilised in 6 M urea. This recombinant GvpC became bound to gas vesicles that had been stripped of their native protein, when the urea was removed by dialysis; the amount which bound increased with the concentration of GvpC present. The critical pressure of these reconstituted gas vesicles increased to 0.533 MPa, 96% of the original value. These results indicate that the function of GvpC is to increase the strength of the structure.


Iron control of the Vibrio fischeri luminescence system in Escherichia coli. Iron influences luminescence in Vibrio fischeri; cultures iron-restricted for growth rate induce luminescence at a lower optical density (OD) than faster growing, iron-replete cultures. An iron restriction effect analogous to that in V. fischeri (slower growth, induction of luminescence at a lower OD) was established using Escherichia coli tonB and tonB+ strains transformed with recombinant plasmids containing the V. fischeri lux genes (luxR luxICDABEG) and grown in the presence and absence of the iron chelator ethylenediamine-di(o-hydroxylphenyl acetic acid) (EDDHA). This permitted the mechanism of iron control of luminescence to be examined. A fur mutant and its parent strain containing the intact lux genes exhibited no difference in the OD at induction of luminescence. Therefore, an iron-binding repressor protein apparently is not involved in iron control of luminescence. Furthermore, in the tonB and in tonB+ strains containing lux plasmids with Mu dI(lacZ) fusions in luxR, levels of beta-galactosidase activity (expression from the luxR promoter) and luciferase activity (expression from the luxICDABEG promoter) both increased by a similar amount (8-9 fold each for tonB, 2-3 fold each for tonB+) in the presence of EDDHA. Similar results were obtained with the luxR gene present on a complementing plasmid. The previously identified regulatory factors that control the lux system (autoinducer-LuxR protein, cyclic AMP-cAMP receptor protein) differentially control expression from the luxR and luxICDABEG promoters, increasing expression from one while decreasing expression from the other. Consequently, these results suggest that the effect of iron on the V. fischeri luminescence system is indirect.


Lethal and mutational effects of solar and UV radiation on Staphylococcus aureus. Strains of Staphylococcus aureus, an opportunistic pathogen commonly found on human skin, were exposed to sunlight and UV C radiation, and the lethal and mutational effects measured. Sunlight killed cells with an inactivation constant of 3 x 10(-5) per joule per square metre; UV C was much more lethal, giving an inactivation constant of approximately 0.1 per joule per square metre. Some strains tested showed a sensitivity to sunlight that was dependent on the growth phase of the cells, exponentially growing cells showing a greater sensitivity. Mutational effects of irradiation were measured by the appearance of mutants sensitive to methicillin following irradiation of a multiresistant strain. Mutants appeared at a frequency of 10(-3); this high frequency of mutation in the region of the mec gene has also been observed when multiresistant strains are subjected to nutritional or thermal stress. Mutants showed the same chromosomal alteration (seen in pulse-field gel electrophoresis of SmaI-digested DNA) whether induced by solar or UV C irradiation.


Clostridium neopropionicum sp. nov., a strict anaerobic bacterium fermenting ethanol to propionate through acrylate pathway. Strain X4 was isolated several years ago from an anaerobic mesophilic plant treating vegetable cannery waste waters. It was the first example of propionic fermentation from ethanol. Morphologic and physiologic characterizations of the strain are presented here. This strain is described as type strain of a new species, Clostridium neopropionicum sp. nov. Whole cells of strain X4 ferment [1-13C] ethanol and CO2 to [2-13C] propionate, [1-13C] acetate and [2-13C] propanol, suggesting the absence of a randomizing pathway during the propionate formation. Enzymes involved in this fermentation were assayed in cell-free extracts of cells grown with ethanol as sole substrate. Alcohol dehydrogenase, aldehyde dehydrogenase, phosphate acetyl transferase, acetate kinase, pyruvate synthase, lactate dehydrogenases, and the enzymes of the acrylate pathway were detected at activities sufficient to be involved in ethanol fermentation. The same pathway may be used for the degradation of lactate or acrylate to acetate.


Uptake of a fluorescent-labeled fatty acid by spiroplasma floricola cells. 12-(1-pyrene)dodecanoic fatty acid (P12) uptake by Spiroplasma floricola BNR-1 cells was characterized with regard to its kinetics, specificity, metabolism and susceptibility to protein and lipid inhibitors. The uptake process depended on temperature and pH, and exhibited biphasic saturation kinetics with a very low (2.7 microM) and a high (37 microM) apparent Km value. Lauric, myristic, palmitic, stearic and oleic fatty acids did not compete with P12 for transport. The fluorescence of P12 was exclusively recovered in the neutral lipid fraction, suggesting that this fatty acid is not further utilized for phospholipid biosynthesis. Valinomycin, carbonylcyanide m-chlorophenyldrazone (CCCP), dicyclohexylcarbodiimide (DCCD), and pronase strongly reduced P12 uptake by cells, but not by membrane vesicles, affecting the high affinity (low Km) component of the uptake system. Uptake of P12 by cells, as well as by membrane vesicles, was very sensitive to glutaraldehyde, chlorpromazine, phospholipase A21 and ascorbate with FeCl3, which affected the low affinity (high Km) component of a transport system. Digitonin stimulated P12 uptake. We suggest that the incorporation of P12 into spiroplasma cell membrane is a two-step process: a high specificity energy-dependent and protease-sensitive binding to the outer surface of membrane, and a low specificity and energy-independent diffusion and partition into the membrane lipid environment.


Distribution and immunological characterization of microbial aldehyde reductases. The distribution of microbial aldo-keto reductases was examined and their immunochemical characterization was performed. p-Nitrobenzaldehyde, pyridine-3-aldehyde and ethyl 4-chloro-3-oxobutanoate reductase activities were found to be widely distributed in a variety of microorganisms. In immunodiffusion studies, most yeasts belonging to the genera Sporobolomyces, Sporidiobolus and Rhodotorula formed precipitin bands with anti-Sporobolomyces salmonicolor aldehyde reductase serum. Furthermore, the results of immunotitration experiments suggested that Sporobolomyces salmonicolor AKU 4429 contains other enzyme(s) which can reduce p-nitrobenzaldehyde, pyridine-3-aldehyde and/or ethyl 4-chloro-3-oxobutanoate, and which are inactivated by anti-Sporobolomyces salmonicolor aldehyde reductase serum.


Environmental regulation of alcohol metabolism in thermotolerant methylotrophic Bacillus strains. The thermotolerant methylotroph Bacillus sp. C1 possesses a novel NAD-dependent methanol dehydrogenase (MDH), with distinct structural and mechanistic properties. During growth on methanol and ethanol, MDH was responsible for the oxidation of both these substrates. MDH activity in cells grown on methanol or glucose was inversely related to the growth rate. Highest activity levels were observed in cells grown on the C1-substrates methanol and formaldehyde. The affinity of MDH for alcohol substrates and NAD, as well as Vmax, are strongly increased in the presence of a Mr 50,000 activator protein plus Mg(2+)-ions [Arfman et al. (1991) J Biol Chem 266: 3955-3960]. Under all growth conditions tested the cells contained an approximately 18-fold molar excess of (decameric) MDH over (dimeric) activator protein. Expression of hexulose-6-phosphate synthase (HPS), the key enzyme of the RuMP cycle, was probably induced by the substrate formaldehyde. Cells with high MDH and low HPS activity levels immediately accumulated (toxic) formaldehyde when exposed to a transient increase in methanol concentration. Similarly, cells with high MDH and low CoA-linked NAD-dependent acetaldehyde dehydrogenase activity levels produced acetaldehyde when subjected to a rise in ethanol concentration. Problems frequently observed in establishing cultures of methylotrophic bacilli on methanol- or ethanol-containing media are (in part) assigned to these phenomena.


Fermentative degradation of glutarate via decarboxylation by newly isolated strictly anaerobic bacteria. Two strains of new strictly anaerobic, gram-negative bacteria were enriched and isolated from a freshwater (strain WoG13) and a saltwater (strain CuG11) anoxic sediment with glutarate as sole energy source. Strain WoG13 formed spores whereas strain CuG11 did not. Both strains were rod-shaped, motile bacteria growing in carbonate-buffered, sulfide-reduced mineral medium supplemented with 2% of rumen fluid. Both strains fermented glutarate to butyrate, isobutyrate, CO2, and small amounts of acetate. With methylsuccinate, the same products were formed, and succinate was fermented to propionate and CO2. No sugars, amino acids or other organic acids were used as substrates. Molar growth yields (Ys) were very small (0.5-0.9 g cell dry mass/mol dicarboxylate). Cells of strain WoG13 contained no cytochromes, and the DNA base ratio was 49.0 +/- 1.4 mol% guanine-plus-cytosine. Enzyme activities involved in glutarate degradation could be demonstrated in cell-free extracts of strain WoG13. A pathway of glutarate fermentation via decarboxylation of glutaconyl-CoA to crotonyl-CoA is suggested which forms butyrate and partly isobutyrate by subsequent isomerization.


The structural genes encoding CO dehydrogenase subunits (cox L, M and S) in Pseudomonas carboxydovorans OM5 reside on plasmid pHCG3 and are, with the exception of Streptomyces thermoautotrophicus, conserved in carboxydotrophic bacteria. Employing deoxyoligonucleotide probes and Southern hybridizations, we have examined in carboxydotrophic bacteria the localization on the genome of genes encoding the large, medium and small subunits of CO dehydrogenase (coxL, M and S, respectively). In Pseudomonas carboxydovorans OM5 coxL, M and S were identified on the plasmid pHCG3; they were absent on the chromosome. This was evident from positive hybridizations with plasmid DNA of the wild-type strain OM5 and the absence of hybridizations with chromosomal DNA from the plasmid cured mutant strain OM5-12. The genes coxL, M and S were found on plasmids in all other plasmid-containing carboxydotrophic bacteria e.g. Alcaligenes carboxydus, Azomonas B1, Pseudomonas carboxydoflava, Pseudomonas carboxydovorans OM2 and OM4. Cox L, M and S could be identified on the chromosome of the plasmid-free bacteria Arthrobacter 11/x, Bacillus schlegelii, Pseudomonas carboxydohydrogena, and Pseudomonas carboxydovorans OM3. These results essentially confirm and extend former reports that cox genes are rather conserved among carboxydotrophic bacteria of distinct taxonomic position. However, Streptomyces thermoautotrophicus is an noteworthy exception since none of the three cox genes could be detected. This refers to a new type of CO dehydrogenase and is in accord with results indicating that the S. thermoautotrophicus CO dehydrogenase has an unusual electron acceptor specificity and some other properties setting it apart from the 'classical' CO dehydrogenases.


Creatinine and N-methylhydantoin degradation in two newly isolated Clostridium species. With N-methylhydantoin (NMH) as the main organic substrate, two strictly anaerobic spore forming Gram-positive bacterial strains were isolated from sewage sludge. These strains, named Clostridium sp. FS23 and Clostridium sp. FS41, totally degraded NMH, via N-carbamoylsarcosine (CS) and sarcosine as intermediates. Strain FS23 grew also with creatinine, which was converted to NMH by creatinine iminohydrolase (EC 3.5.4.21). This enzyme was formed at high rates with all substrates tested. Cytosine and 5-fluorocytosine were not utilized as substrates by creatinine iminohydrolase preparations purified to a homogeneity of 98%. NMH amidohydrolase (NMHase) and N-carbamoylsarcosine amidohydrolase (CSHase) turned out to be inducible in both strains. Other than in aerobic organisms, NMHase from these two isolated did not require ATP for enzymatic activity. SH-group protecting agents were not necessary for stability.


Relationship between size of parent at cell division and relative size of its progeny in Escherichia coli. This article examines the empirical basis for the assumption of independence between the relative size (length or surface area) of a newborn cell w and the absolute size of its mother at cell division. Random samples from two strains of Escherichia coli B/r cells in steady-state exponential growth, covering a range of doubling times, were fixed in osmium tetroxide and prepared for electron microscopy by agar filtration. Length and diameter of over 3000 constricted cells were measured from the electron micrographs and cell surface area computed by assuming an idealized geometry of right circular cylinders with hemispherical polar caps. In general, these strains were found to divide into two daughter cells with a precision that is independent of the size of the mother. In addition, both a normal and a symmetrical beta-distribution were shown to fit the observed size distributions of w rather well; theoretical grounds for preferring the latter are discussed.


Biological effects of tolytoxin (6-hydroxy-7-O-methyl-scytophycin b), a potent bioactive metabolite from cyanobacteria. Tolytoxin, a macrocyclic lactone, is a potent antifungal antibiotic, exhibiting MICs in the range of 0.25 to 8 nanomolar. Tolytoxin also inhibits the growth of a variety of mammalian cells at similar doses, without specific inhibition of macromolecular synthesis. The effects in mammalian cells are primarily cytostatic, with cell death being time- and dose-dependent. Tolytoxin is highly toxic to mice, exhibiting an LD50 (ip) of 1.5 mg/kg. No antibacterial, antiviral, or hemolytic activities were observed.


Characterization of urease from Sporosarcina ureae. Alkaline stable (pH 7.75-12.5) urease from Sporosarcina ureae was purified over 400-fold by ion exchange and hydrophobic interaction chromatography. The cytoplasmic enzyme was remarkably active with a specific activity of greater than 9300 mumol urea degraded min-1 mg protein-1 at pH 7.5, where it has optimal activity. Although S. ureae is closely related to Bacillus pasteurii, known to possess a homopolymeric urease containing 1 nickel per subunit [M(r) = 65000], the S. ureae enzyme is comprised of three subunits [apparent M(r) = 63,100 (alpha), 14,500 (beta), and 8500 (gamma)] in an estimated alpha beta gamma 2 stoichiometry and contains 2.1 +/- 0.6 nickel ions per alpha beta gamma 2 unit as measured by atomic absorption spectrometry. Stationary phase cultures sometimes possessed low levels of urease activity, but the specific activity of cell extracts of partially purified urease preparations from such cultures could be elevated by heat treatment, dilution, or dialysis to values comparable to those observed in samples from exponentially grown cells.


Studies on the effect of NAD(H) on nitrogenase activity in Rhodospirillum rubrum. The effect of NAD(P) and analogs of this nucleotide on nitrogenase activity in Rhodospirillum rubrum has been studied. Addition of NAD+ to nitrogen fixing Rsp. rubrum leads to inhibition of nitrogenase. NADP+ has the same effect but NADH or analogs modified in the nicotinamide portion do not cause inhibition. In contrast to ammonium ions, addition of NAD+ leads to inhibition of nitrogenase in cells that have been N-starved under argon. The inhibitory effect of NAD+ is more pronounced at lower light intensities. Addition of NAD+ also leads to inhibition of glutamine synthetase, a phenomenon also occurring when "switch-off" is produced by the addition of effectors such as ammonium ions or glutamine. It is also shown that NAD+ is taken up by Rsp. rubrum cells.


Growth yield increase and ATP formation linked to succinate decarboxylation in Veillonella parvula. Veillonella parvula strain 259 (= DSM 2007) was able to grow on a mineral salts medium supplemented with (per litre) 1 g yeast extract, 1 g Tween-80, and 3 mg putrescine.2 HCl, with 6 mM thioglycolate as reductant and lactate as growth substrate. Succinate did not serve as a growth substrate, but when added in conjunction with lactate, it was decarboxylated to propionate and resulted in a measurable increase in growth yield, corresponding to the formation of 2.4 g cell dry mass per mol succinate. A growth yield increase linked to succinate metabolism occurred only while lactate was also being metabolised. Experiments with cell suspensions showed that succinate decarboxylating activity was constitutive. Addition of succinate produced clear increases in cellular ATP levels in ATP-depleted washed cells.


Heterogeneity of lipoteichoic acid detected by anion exchange chromatography. A complex polydispersity became apparent when the poly(glycerophosphate) lipoteichoic acid of Enterococcus faecalis was chromatographed on DEAE-Sephadex. The chain length varied between 13 and 33 glycerophosphate residues per lipid anchor. In parallel, the extent of chain glycosylation increased from 0.2 to 0.4 diglucosyl residues per glycerophosphate unit. Substitution with D-alanine ester showed a reverse distribution dropping with increasing chain length from 0.53 to 0.23 mol D-alanine per mol phosphorus. Variations in the fatty acid composition were also observed. The results extent and modify the current picture of lipoteichoic acid biosynthesis. They further suggest that during infection the mammalian organism may be confronted particularly with long-chain less hydrophobic molecular species.


Purification of a periplasmic insulin-cleaving proteinase from Acinetobacter calcoaceticus. Cells of Acinetobacter calcoaceticus contain a constitutive periplasmic metalloproteinase showing similar properties as the periplasmic metalloproteinase of Escherichia coli. The periplasmic proteinase of A. calcoaceticus was purified, starting from periplasm, by ammonium sulfate precipitation, hydrophobic interaction chromatography and chromatofocusing up to the homogeneity of the enzyme in SDS-electrophoresis with a yield of 6.7% and a purification factor of 417. The enzyme has a molecular mass of 108,000 (gel filtration) or 112,000 (native electrophoresis), and consists of four identical subunits with a molecular mass of 27,000 (SDS-electrophoresis). The purified enzyme degrades preferentially polypeptides such as glucagon and insulin. Larger proteins are accepted as substrates to a considerably lower extent. All tested synthetic substrates with trypsin, chymotrypsin, elastase and thermolysin specificity were not cleaved. Therefore, the described enzyme was designated "insulin-cleaving proteinase" (ICP).


Energy conservation in malolactic fermentation by Lactobacillus plantarum and Lactobacillus sake. A comparably poor growth medium containing 0.1% yeast extract as sole non-defined constituent was developed which allowed good reproducible growth of lactic acid bacteria. Of seven different strains of lactic acid bacteria tested, only Lactobacillus plantarum and Lactobacillus sake were found to catalyze stoichiometric conversion of L-malate to L-lactate and CO2 concomitant with growth. The specific growth yield of malate fermentation to lactate at pH 5.0 was 2.0 g and 3.7 g per mol with L. plantarum and L. sake, respectively. Growth in batch cultures depended linearly on the malate concentration provided. Malate was decarboxylated nearly exclusively by the cytoplasmically localized malo-lactic enzyme. No other C4-dicarboxylic acid-decarboxylating enzyme activity could be detected at significant activity in cell-free extracts. In pH-controlled continuous cultures, L. plantarum grew well with glucose as substrate, but not with malate. Addition of lactate to continuous cultures metabolizing glucose or malate decreased cell yields significantly. These results indicate that malo-lactic fermentation by these bacteria can be coupled with energy conservation, and that membrane energetization and ATP synthesis through this metabolic activity are due to malate uptake and/or lactate excretion rather than to an ion-translocating decarboxylase enzyme.


Anaerobic malonate decarboxylation by Citrobacter diversus. Growth and metabolic studies, and evidence of ATP formation. Citrobacter diversus ATCC 27156 was able to grow by decarboxylation of malonate to acetate under strictly anaerobic conditions, in the presence of yeast extract. The growth yield, corrected for growth on yeast extract, was 2.03 g cell dry mass per mol malonate. The addition of malonate to ATP-depleted cell suspensions (less than 0.2 nmol ATP/mg cell protein) resulted in a rapid increase in cellular ATP levels to between 4.5 and 6.0 nmol/mg cell protein. Intact cells decarboxylated malonate at rates of up to 1.5 mumol/min.mg protein. Enzyme assays on malonate-grown cells indicated activation of malonate by an ATP-dependent ligase reaction and by CoA transfer from acetyl-CoA, followed by decarboxylation of malonyl-CoA to acetyl-CoA with subsequent recovery of the invested ATP by substrate level phosphorylation through the activity of acetate kinase. Net ATP synthesis is postulated to be mediated by gradient formation coupled to the decarboxylation of malonyl-CoA. The protonophore CCCP and H(+)-ATPase inhibitor DCCD significantly reduced cellular ATP levels, suggesting a role for proton gradients in the energy metabolism of this strain when growing an malonate. Inhibitors of sodium metabolism or ommission of sodium had no effect on ATP levels or malonate decarboxylation.


Decreased hepatic phosphoenolpyruvate carboxykinase gene expression after 2,3,7,8-tetrachlorodibenzo-p-dioxin treatment: implications for the acute toxicity of chlorinated dibenzo-p-dioxins in the rat. Decreased activity of the rate limiting gluconeogenic enzyme, phosphoenolpyruvate carboxykinase (PEPCK), has been recently suggested to be the critical lesion in the acute toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). We now show that other toxicologically relevant chlorinated dibenzo-p-dioxins (CDDs), with chlorine substituents in the crucial 2-,3-,7-, and 8-positions, exert the same effect on PEPCK activity. The doses required to cause this enzyme inhibition are within the acutely toxic range for each homologue, suggesting the same mechanism of action for these compounds. To further investigate the mechanism whereby dioxins decrease PEPCK activity, Northern analysis was performed using a cDNA probe complementary to a portion of the PEPCK mRNA. We could demonstrate that after TCDD treatment hepatic PEPCK mRNA was decreased by as much as 90% compared to pair-fed control animals (day 8 after dosing). This decrease in PEPCK mRNA was paralleled by a decrease of the amount of PEPCK protein and enzymatic activity. These results indicate that the physiological changes which occur in TCDD-treated animals (decreased feed consumption, low plasma insulin and elevated plasma corticosterone levels) which under normal conditions increase PEPCK gene expression and enzyme activity, are not effective in stimulating PEPCK synthesis in TCDD-treated animals.


Blood mercury and serum selenium concentrations in reindeer herders in the arctic area of northern Finland. 163 healthy reindeer herders living in the arctic area of northern Finland were investigated for blood mercury and serum selenium concentrations. More than ten percent of the subjects had blood mercury above the upper normal limit. High organic and total organic mercury levels were most common in the northeastern part of the country. High organic and total mercury and selenium values were more common in the Lapps than the Finns. Blood mercury levels increased with increasing fish consumption. The pollution in the northeastern part of this country probably leads to the increased formation of organic mercury, and its enrichment in the food chain. The association of high selenium with high mercury probably reduces the toxicity of the latter.


Variations in prevalence of endocrine tumors among different colonies of rats? A retrospective study in the Hannover registry data base. Illustrated by data derived from the endocrine system it could be demonstrated that at least the following requirements have to be fulfilled when using historical control data for the interpretation of animal studies: The main and basic requirement is the utilization of standardized diagnostic criteria and a systematized nomenclature for all data which should be compared. This includes the historical control data as well as histopathological diagnoses obtained from other animal studies. All findings stored in the REGISTRY are based on standardized criteria and this nomenclature was also applied for the more recent studies which were evaluated by pathologists of the member companies. Data from literature which are frequently used for comparison and interpretation cannot always fulfill this requirement due to the variation of diagnostic criteria used by different investigators. The second important requirement is an exact knowledge of study-related details. Some dependencies of the tumor rate on the sex, the strain, the breeder and the age were shown in a few examples. But other parameters, like diet, caging, bedding etc. may also influence the frequency of spontaneously occurring tumors and therefore have to be taken into account. In the REGISTRY such data from routine carcinogenicity and toxicity studies are available because all these studies are performed under GLP conditions and all parameters are carefully recorded. During the relatively short period of its activity, the REGISTRY has become not only source of historical laboratory data, but also it subserves as indispensable tool of quality control warranted by peer-review effects of panel meetings. An additional benefit will emanate from the data base in the near future: Exact knowledge of the magnitude of the influence of distinct parameters will enable the member companies to use the information for the design or optimization of new studies, as well as to extend the analysis and support the interpretation of observed results.


Biologically based modeling in toxicology research. Biologically based modeling can be described as the process by which the specific mechanistic steps governing tissue disposition and toxic action of chemicals are expressed in quantitative terms by a set of equations leading to prediction of the outcome of specific toxicological experiments by computer simulation. These models are useful in risk assessment because their mechanistic biological basis permits the high-to-low dose, route to route and interspecies extrapolation of the tissue disposition and toxic action of chemicals. By far their greatest utility is not as "finished" risk assessment models, but as research tools that convey a quantitative expression of our hypotheses of tissue disposition and toxic action of a chemical. A structured modeling approach to toxicology problems helps identify the data gaps in the areas of chemical disposition and toxic action, thus prioritizing on-going research to obtain critical information required to conduct quantitative risk assessment. This paper examines progress in developing comprehensive biologically based models for cancer induction by non-genotoxic carcinogens that are cytotoxic in target tissues. The strategies for linking the models on dosimetry, cytotoxicity, and carcinogenicity are described in detail. The basic concepts and approaches discussed here can be applied to many other toxic chemicals and to toxicity endpoints other than cancer.


Multi-compartment model to study the effect of air-blood and blood-tissue partition coefficients on concentration-time-effect relationships. The influence of the air-blood (lambda) and blood-tissue partition coefficients of substances on the concentration-time-effect relationship E = [aCnT]b was studied by model simulation of uptake and distribution of gases. The model consisted of a lung compartment and four tissue compartments. Rat and human model parameters were obtained from physiological data, and substance-dependent variables. The observable effect E (righting reflex, mortality, etc.) for directly acting systemic agents was supposed to be related to the (arbitrarily chosen) concentration of the substance in the arterial blood or in the liver compartment. We conclude that for a directly acting systemic agent n greater than or equal to 1. If n less than 1 other mechanisms such as metabolism must be incorporated in the model which, however, should not be excluded when n greater than or equal to 1. If the observable effect is related to arterial concentration of the substance, n increases with decreasing lambda. If the liver concentration is related to the observable effect, man and rat may behave quite differently. This has major consequences for the extrapolation of animal results to the human situation in risk assessment.


[Immunologic reaction and ventilatory function in hemp-processing workers]. The relationship between immunological status and respiratory function was studied in 42 hemp workers and in 49 control workers. The highest prevalence of positive skin tests was recorded for a mixture of hemp and flax (64%), followed by flax (48%), hemp on a combining machine (41%), hemp on a carding machine (38%), hemp on spinning and weaving machines (33%), and hemp on a softening machine (20%). The prevalence of positive skin tests in control workers was smaller and varied from 21 to 5%. Increased IgE was found in 35.7% of the hemp workers and in 5.0% of the controls (P less than 0.05). Hemp workers with positive skin tests had a significantly higher prevalence of chronic respiratory symptoms than those with negative skin tests. Acute ventilatory capacity reductions did not differ in respect to the immunological status. An extract of hemp dust caused a constriction of an isolated guinea pig tracheal smooth muscle in vitro. Our data suggest that hemp dust as well as producing an immunological effect may exert an irritant effect on the respiratory system in exposed textile workers.


[Isoproterenol toxicity in the myocardium in an experiment]. The effect of toxic doses of isoproterenol (ISP) on total activities and isoenzyme patterns of creatine kinase (CK) and lactate dehydrogenase (LDH) in rat sera was investigated and correlated with histopathological changes in the myocardial tissue. A single dose of 25 mg ISP per 100 g body weight caused a statistically important elevation of CK and LDH total activities and of the activities of cardiospecific isoenzymes CK-MB, LDH-1 and LDH-2 six hours after intraperitoneal administration. The isomorphic LDH isoenzyme pattern, which was also observed, was taken to be a proof of the ISP-induced cardiogenic shock. The increase in the activity of CK-MM and LDH-5 isoenzymes could be explained as a secondary consequence of cardiogenic shock and of the consecutive damage of the tissue with anaerobic metabolism such as liver. The findings were confirmed by a histopathological analysis showing the development of coagulative necrosis and myocytolysis as well as undulations of heart muscle cells as a sign of cardiogenic shock.


[Xenobiotic and biochemical parameters of isolated rat hepatocytes]. The authors investigated the effects of the inductors (griseofulvin and fenitoin) and the inhibitors of the cytochrome P-450 (metronidazole, chloramphenicol and phenylbutazone), the effects of the drugs with the purine structure (aminophylline, xanthinol-nicotinate, pentoxiphylline, azathioprine, thioguanine, 6-mercaptopurine), and the effects of several pesticides (lindane, binapicrile, parathion) on some biochemical parameters of the rat liver. The following parameters were determined: viability of hepatocytes, the content of glutathione and cytochrome P-450, and the activity of xanthinoxidase and lipoperoxidase. The experiments were performed in vivo and in vitro. The results showed that the cell viability as well as the other parameters studied, were most drastically affected by chloramphenicol, azathioprine and parathion, whereas the other substances elicited less intensive changes.


[Cytogenetic changes in persons exposed to polychlorinated biphenyls]. A cytogenetic study performed in a group of workers exposed to polychlorinated biphenyls comprised analysis of structural chromosomal aberrations in the lymphocytes in the first division in vitro, analysis of micronuclei frequency in binuclear lymphoblasts induced by cytochalasin B and analysis of sister chromatid exchanges. The study included 48 exposed workers and 15 controls. In 16 exposed workers increased incidence of unstable chromosomal aberrations (dicentrics, rings and acentrics) was found, while in 19 no structural chromosomal aberrations could be detected. In 11 workers changes defined as chromosomal and chromatid breaks were noted. This type of change, however, can be evidenced in a non-exposed population as well. In two workers stable chromosomal aberrations were recorded (translocations and inversions). The incidence of micronuclei as well as exchange of sister chromatids were elevated in the exposed group of workers compared to controls.


[The effect of occupational noxae in the tobacco industry on pulmonary function in exposed workers]. A study was carried out to determine respiratory hazards to workers in tobacco manufacture. The investigations at the workplace included analysis of the work technology and measurements of chemical pollutants and dust concentrations in the work rooms. Ventilatory lung function tests were performed in 95 workers exposed to tobacco dust and in 129 control workers. Results of workplace analysis showed the presence of tobacco dust levels exceeding the maximum permissible concentrations. The values of some lung function tests for exposed workers non-smokers were significantly lower than for control workers non-smokers. They could be attributed to the effect of occupational noxae on the respiratory system.


[Epidemiologic and sociologic aspects of occupational bronchial asthma]. The main problems confronted in epidemiological investigations of occupational bronchial asthma are described, such as the absence of a definition of the disease, the need for a standardized questionnaire for the symptoms of the disease and the heterogeneity of the functional lung tests. The questionnaires most frequently used for respiratory symptoms and the most suitable tests for measuring and evaluating ventilatory lung function are discussed. The problem of identifying the persons who are at risk of developing occupational bronchial asthma is also dealt with.


[Psychological methods in the evaluation of neurotoxic effects of organic solvents]. Organic solvents comprise a large and heterogenous group of chemical compounds and mixtures, largely belonging to volatile hydrocarbons. They are widely used in various industries. Long-term exposure to organic solvents as a cause of the central nervous system impairement has been subject of extensive epidemiological and clinical studies for years, especially in Scandinavia, but often with inconsistent results. In 1985 the World Health Organization published the criteria for the evaluation of neurotoxic effects of solvents that are now commonly accepted. The present paper provides a short review of the current state of knowledge in the field emphasizing the role of neuropsychological methods in assessing solvent toxicity.


Hip pain in children.

Hip pain in children. Children who present with a limp and pain in the hip, anterior thigh and the knee can have a serious disorder of the hip. The age at presentation tends to provide a guide to the possible problem, such as a slipped upper femoral epiphysis and a stress fracture of the femoral neck in adolescents.


Cosmetic surgery for the ageing face.

Cosmetic surgery for the ageing face. Cosmetic surgery is unique in that the results are qualitative. Recent technical advances now allow the skilled and artistic surgeon to achieve the degree of change requested by most patients, without the obvious operated look. General practitioners should extend their professional relationship with cosmetic surgery patients. Preliminary counselling can reduce patient's anxiety by clarifying their objectives and by providing relevant information and support. The relationship of trust so engendered is helpful for post operative support and allows the practitioner to share in the satisfaction experienced by the patient as a result of surgery.


The injured hand.

The injured hand. Careful evaluation and diagnosis of the injured hand, with appropriate early treatment, can reduce the morbidity of a hand injury substantially. Aim for uncomplicated primary healing of injured structures, keeping oedema, inflammation and subsequent scar immobility to a minimum. If the repair is beyond your surgical skills or experience--refer early.


Common pitfalls in plastic surgery from the GP perspective. General practitioners are responsible for the overall management of patients and their expertise is invaluable in this respect. With the ever changing horizons in disease processes and therapeutics, the dedicated family physician has more knowledge in general than many of his specialist colleagues. It is unfair, however, to expect general practitioners to have an in-depth knowledge of all conditions. These notes, I believe, offer family practitioners some beneficial information on possible pitfalls. My plastic surgeon colleagues would agree, I am sure, that further advice on any dilemma is merely a telephone call away.


Recent advances in plastic surgery.

Recent advances in plastic surgery. Scarless healing and the creation of like-tissue for reconstruction have been the aims of plastic surgery since its inception. Recent advances bring us even closer to the ideal.


Liver transplantation in the 1990s.

Liver transplantation in the 1990s. Liver transplantation is now the therapy of choice for advanced, irreversible, progressive liver disease. The authors look at who should have a transplant and explain that the predicted outcomes of surgery depend on the pre-operative disease. A brief overview of post-operative care is given.


Barriers to cervical screening in older women. To explore the reasons why some older women do not have regular Papanicolaou smear tests. The Ballarat region of Victoria. Cross-sectional survey administered by telephone interview. Three hundred and forty-seven women aged 40 to 70. 1. 41% of women had not had a Papanicolaou smear test within the preceding 2 years. 2. Women who agreed with the statement that healthy women do not need to have Papanicolaou tests were six times more likely to be overdue for a Papanicolaou test than women who did not agree. 3. Being over 60 significantly increased the likelihood that a woman would be overdue for a Papanicolaou test, compared with younger women. 4. Women who thought that the test is only needed at intervals of 3 years or more were over six times more likely to be overdue than women who believed the interval to be 2 years or less. 5. Women who perceived themselves as being too embarrassed were nearly seven times more likely to be overdue than women who claimed no embarrassment. 6. Women who saw themselves as being too busy to have the test were three times more likely to be overdue than women who did not see themselves this way. 7. Women with a spouse were less likely to be overdue than other women. 8. Women who knew to start having Papanicolaou tests when they were sexually active were less likely to be overdue than women who did not know this. Many of these barriers can be overcome by the clinician in routine practice.


The effect of trans-cockpit authority gradient on Navy/Marine helicopter mishaps. Navy and Marine Corps helicopter mishaps which had a pilot causal factor assigned were examined to determine if the relative military rank of the pilot and copilot was associated with the rate of occurrence per 100,000 flight hours. All class A and B helicopter flight mishaps for the 11 calendar year period 1980-1990 were examined. Although no statistically significant differences were noted, pairing pilots who were of equal rank yielded the lowest rate, seemingly refuting Elwyn Edward's notion that a flat "trans-cockpit authority gradient" may lead to greater problems in the cockpit than his hypothetical "optimum gradient." Moreover, when copilots flew with pilots who differed by two or more ranks, the largest pilot error rate was revealed. This last finding seems to support Edward's hypothesis that a steep "trans-cockpit authority gradient" may be detrimental to aviation safety.


Cardiovascular responses to positive pressure breathing using the tactical life support system. The improved protection afforded by the Tactical Life Support System (TLSS) vs. other partial pressure ensembles has not been reported with respect to the cardiovascular effects of positive pressure breathing (PPB). Nine seated subjects wearing TLSS were exposed to 30, 50, and 70 mm Hg PPB (breathing air) with four times this pressure in the G-suit. Experiments were conducted at ground-level in order, separated by 4 min rest and preceded by a 1-min control period. Stroke volume and cardiac output (SV, CO) and indexes (SI, CI) were determined by impedance cardiography. Mean arterial pressure (MAP) was directly related to PPB level, increasing by 23%, 32%, and 47% for each PPB level, respectively (p less than 0.01). HR, SV, and CO were unaffected after 4 min of 30, 50, and 70 mm Hg PPB. The results indicate that cardiovascular function decay is less severe than that reported using other PPB ensembles at similar PPB levels. Improved protection is most likely due to the greater pressurization of the G-suit and the 45% greater bladder volume in the leg bladders, leading to restored venous return and SV.


Maximum intra-thoracic pressure with anti-G straining maneuvers and positive pressure breathing during +Gz. Positive pressure breathing during +Gz (PBG) and anti-G straining maneuvers (AGSM) each improve +Gz tolerance by increasing blood pressure through increases in intra-thoracic pressure, but the maximal intra-thoracic pressure from their combined effect is not known. Six subjects performed the following: 1) maximal AGSM at +1 Gz; 2) assisted PBG (constant 60 mm Hg) at +Gz; 3) submaximal AGSM at +Gz (enough to maintain peripheral vision); 4) maximal AGSM at +Gz; and 5) combined PBG and maximal AGSM at +Gz. They wore TLSS mask/helmet ensemble, CSU-15/P G-suit, and TLSS-style jerkin. Intra-thoracic pressure was measured with a catheter-tip pressure transducer in the esophagus (Pes). The change in gastric pressure was also measured (delta Pga). For both Pes and delta Pga, there were no significant differences among experimental conditions (1), (4) and (5), as above. Group mean Pes and delta Pga in these three conditions were 139 and 197 mm Hg, respectively. The similar results between maximal AGSM, and maximal AGSM and PBG are explained by limited support from the thoracic counter-pressure garment, and the characteristics of the respiratory system.


Adaptations to unilateral lower limb suspension in humans. This study examined the effect of unilateral lower limb suspension (ULLS) on neuromuscular function in humans. Eight subjects (31 +/- 4 years old) performed all ambulatory activity on crutches for 6 weeks while wearing a shoe with a 10-cm sole on the right foot to unweight the left lower limb. Knee extensor (KE) torque during eccentric, concentric, and isometric actions, and electromyography (EMG) of m. vastus lateralis (m. VL), m. gastrocnemius medialis (m. GM) and m. soleus (m. SL) during isometric actions were assessed pre-ULLS, post-ULLS, and after 4 d of recovery. Average muscle cross-sectional area (CSA) of the KE was measured pre- and post-ULLS and that of the ankle extensors (AE) post-ULLS using magnetic resonance imaging. Strength of the KE of the suspended left limb was reduced (p less than 0.05) 21 and 15%, respectively, after ULLS and 4 d later. Average muscle CSA of the left KE decreased (p less than 0.05) 16%. The KE of the non-suspended right limb showed no changes in muscle CSA. Thus, average muscle CSA of the KE of the suspended limb was 17% less (p less than 0.05) than that of the non-suspended limb. Average muscle CSA of the AE, likewise, was smaller (18%, p less than 0.05) in the left than right leg after ULLS. Maximal integrated EMG of VL and overall mean power frequency of GM and SL for submaximal isometric actions were both decreased (p less than 0.05) post-ULLS.(ABSTRACT TRUNCATED AT 250 WORDS)


Exercise performance, core temperature, and metabolism after prolonged restricted activity and retraining in dogs. To study physiological effects of restricted activity (RA) and subsequent retraining, 10 male mongrel dogs (1-5 years) performed a submaximal exercise endurance test on a treadmill (12 degrees slope, 1.6 m.s-1) during kennel control, after 8 weeks of cage (40 cm-w x 80 cm-h x 110 cm-l) confinement, and after 8 weeks of retraining using the same treadmill protocol 1 h/d for 6 d/week. Compared with control endurance (172 +/- 19 min), endurance decreased to 102 +/- 15 min (delta = -41%, p less than 0.05) after RA and increased to 223 +/- 24 min (delta = +30%, p less than 0.05) after training: the respective final levels and changes in rectal temperature were 41.25 and +2.15 degrees C, 41.60 and +2.70 degrees C (NS), and 41.35 and +2.40 degrees C (NS), respectively. Resting and post-exercise blood glucose and lactate concentrations were unchanged in the three experiments. After RA, resting muscle glycogen was reduced from a control level of 49.9 +/- 4.3 to 34.1 +/- 4.5 mmol.kg-1 (delta = 32%, p less than 0.05) which returned to the control level of 58.4 +/- 3.5 mmol.kg-1 after retraining. Resting plasma FFA levels were unchanged, but the RA post-exercise change was decreased from a control level of +0.400 +/- 0.099 to +0.226 +/- 0.039 mmol.L-1 (p less than 0.05). Neither restricted activity nor training affected glucose tolerance significantly. The results indicated that RA reduces exercise endurance, the effectiveness of exercise thermoregulation, muscle glycogen stores, and the lipolytic response to exercise and to noradrenaline stimulation. All these changes were reversed following 8 weeks of retraining.


Influence of self-induced hypnosis on thermal responses during immersion in 25 degrees C water. The efficacy of self-induced post-hypnotic suggestion to improve thermogenic responses to head-out immersion in 25 degrees C water was evaluated in 12 males. An on-line computerized system permitted the change in body heat storage to be used as the independent variable and immersion time as the dependent variable. Test-retest reliability was good, exhibiting a coefficient of variation of less than 5% for exposure time. Immersion profiles consisted of the following: rest until 200 kJ of heat were lost, leg exercise at VO2 approximately 1.5 L.min-1 to regain 200 kJ, rest until 100 kJ were lost, and repeat the exercise to regain 100 kJ. A control immersion was done prior to two 1-h hypnotic training sessions. A second immersion (hypnotic) occurred within 24 h after training. There were no differences in rates of heat production, heat loss, mean skin temperature, or rectal temperature between control and hypnotic immersions. Individual hypnotic susceptibility scores did not correlate with changes in thermal status. Ratings of perceived exertion during exercise were similar for both immersions, but perceived sensation of cold was lower during the second rest period of the hypnotic immersion. Three subjects used images of warm environments during their hypnotic immersion and lost heat at a faster rate than during control immersions. These results indicate that brief hypnotic training did not enhance the thermogenic response to cool water immersion.


Effect of high terrestrial altitude and supplemental oxygen on human performance and mood. Sustained exposure to high terrestrial altitudes is associated with cognitive decrement, mood changes, and acute mountain sickness (AMS). Such impairment in aviators could be a safety hazard. Thirteen male soldiers, ages 19-24, ascended in 10 min from sea level to 4,300 m (simulated), and remained there 2.5 d. Four times per day, subjects completed a test battery consisting of nine cognitive tests, a mood scale, and an AMS questionnaire. During one test session per day, subjects breathed 35% oxygen instead of ambient air. Analysis revealed transient deficits on altitude day 1 for three cognitive tasks. Most tasks displayed a persistent training effect. Sick subjects' moods were more negative and their performance improvement less. On altitude day 1, oxygen administration improved performance on two cognitive tests and one mood subscale. Following rapid ascent to 4,300 m, performance is most affected during the first 8 h. Individuals affected by AMS tend to improve more slowly in performance and have more negative moods than those who feel well.


Emesis in ferrets following exposure to different types of radiation: a dose-response study. Ferrets were exposed to gamma rays (60Co), fission neutrons, high-energy electrons (18.5 MeV) or iron particles (56Fe, 600 MeV/amu) in order to establish the dose-response relationships for emesis following exposure to different types of radiation. The results showed that the mean effective doses (ED50s) for iron particles (35 cGy) and neutrons (40 cGy) were similar. High-energy electrons were the least effective radiation, with an ED50 of 138 cGy. Gamma rays, with an ED50 of 95 cGy, showed an intermediate effectiveness. The results suggest that the relative effectiveness of different types of radiation generally increases with an increase in linear energy transfer (LET), although LET is not completely predictive of relative behavioral effectiveness.


The effect of captopril on +Gz tolerance of normotensives. Recently, there has been considerable interest in whether angiotensin converting enzyme inhibitors can be used to treat hypertensive pilots without compromising their operational effectiveness. This study was undertaken to evaluate the possible effects of captopril on tolerance to +Gz, of relevance in tactical fighter operations. A counterbalanced double blind crossover protocol was used to administer 25 mg of captopril or placebo twice daily in identical capsules to seven fit, normotensive individuals from the DCIEM acceleration research panel. The five males and two females took each course of capsules for 4 d prior to G-tolerance assessment and waited 1 week for drug wash-out after assessment on their first condition prior to commencement of the second course of capsules. The subjects did not wear G-suits. Standard ASCC gradual onset runs, relaxed and with a straining maneuver, and rapid onset runs were used to assess G tolerance. The group G tolerances are listed as mean +/- S.E.M.: during relaxed gradual onset runs (GOR) 3.96 +/- 0.14 on placebo and 3.61 +/- 0.10 on captopril (p = 0.02, paired t-test). Corresponding results for relaxed rapid onset runs (ROR) were 3.36 +/- 0.17 on placebo and 3.33 +/- 0.18 on captopril (p = 0.21, Wilcoxon signed ranks test). The straining tolerances during GOR runs were 7.21 +/- 0.23 on placebo and 6.83 +/- 0.25 while on captopril (p = 0.05, paired t-test). Given the relatively low dosage and the significant compromise of Gz-tolerance on both relaxed and straining GOR runs, caution is recommended in using captopril to treat hypertensive fighter aircrew.(ABSTRACT TRUNCATED AT 250 WORDS)


Effect of Gz forces and head movements on cervical erector spinae muscle strain. A portable surface-integrated EMG (IEMG) device was used to investigate the strain caused by low and high Gz forces and head movements on the cervical erector spinae muscles during flight missions. The obtained IEMG activities were normalized by comparing them with activities representing maximal voluntary contraction (MVC) of the cervical erector spinae muscles in each subject. The muscular strain increased with increasing Gz forces and head movements. Under +7.0 Gz the mean muscular strain was 5.9-fold compared with +1.0 Gz and was 37.9% of the MVC. In some individuals, the muscular tolerance (100% of the MVC) was ipsilaterally reached already under +4.0 Gz with concomitant movements and twisted positions of the head. Pilots are susceptible to acute neck injury when the protection afforded by their neck muscles is insufficient.


Treatment of acute diarrhea with norfloxacin during Desert Storm deployment. A retrospective study on the treatment of diarrhea in a U.S. Air Force Wing deployed to Egypt during Operation Desert Storm was conducted. Two groups of patients were compared for treatment efficacy. One group was treated with norfloxacin 800 mg as a single dose with the onset of symptoms. The other group was treated conservatively. The group treated with norfloxacin was noted to become asymptomatic in one-fourth the time of the group treated conservatively. This was highly significant, statistically, and in practice. It is recommended that diarrhea be treated aggressively during deployments to third world countries.


Crewmember communication in space: a survey of astronauts and cosmonauts. A total of 54 astronauts and cosmonauts returned questionnaires which addressed various aspects of crewmember communication in space. All respondents believed that crewmembers should be fluent in one shared common language, but American and Soviet space travelers were less tolerant of dialect differences than their international counterparts. Sensory activities (Watching and Listening) were rated as significantly increasing in space, whereas more complex communicative activities (Reading, Gesturing, and Writing) were judged to significantly decrease. Cosmonauts scored higher than astronauts in all verbal and nonverbal activities, possibly reflecting more responsiveness to the space environment. Several factors were rated as significantly helping intracrew communication: Shared Experience, Excitement of Space Flight, Close Quarters, and Isolation from Earth. Other factors were judged to significantly hinder communication: Facial Swelling, Spacecraft Ambient Noise, and Space Sickness. These findings have important operational and scientific implications involving future manned space missions.


Injuries associated with the use of ejection seats in Finnish pilots. During the years 1958-91 17 Finnish pilots were forced to use ejection seats. The aircraft types were as follows: a) BA Hawk in 6 instances; b) a Mig 21-F-13 in 4; c) a Mig-21-Bis in 3; d) a Gnat Folland in 2; e) a Vampire Trainer in 1; and f) a MU-3 in 1 case. There were 3 ejections completed successfully, 12 pilots sustained slight injuries, and 5 pilots suffered major injuries--3 from compression fractures of the thoracic spine, 1 from fracture of the femur, and 1 from rupture of the medial collateral ligament of the knee. All major injuries were associated with Soviet aircraft. One BA-Hawk pilot died due to a direct impact against a tree after a low-altitude ejection. Two pilots launched the seat under negative G-forces. One of these became temporarily blind, and suffered a partial loss of vision for 3 months. Four Hawk pilots were saved during landing phase by a tandem ejection, receiving only minor injuries.


The origin of the electrophoretic doublet of thyroglobulin. Bovine and human thyroglobulin show two closely migrating bands in reducing SDS-PAGE. Limited digestion with chymotrypsin, trypsin and thermolysin converted the slower band of the doublet into a peptide identical to the faster band, with an apparent mass of 270 kDa, in both species. The starting point of the faster band of the doublet was established at Ileu 520 with native bovine Tg and at Ser 503 with native human Tg, and at Ser 503 and Ser 504 with chymotrypsin-digested bovine and human Tg, respectively. These data explain the electrophoretic heterogeneity of thyroglobulin and unveil a region highly susceptible to proteolysis at about 500 residues from the NH2-terminus of the molecule.


Neurocalcin, a novel calcium binding protein with three EF-hand domains, expressed in retinal amacrine cells and ganglion cells. Neurocalcin (molecular weight 23,000 and 24,000) is a newly identified Ca2+ binding protein with three EF-hand domains and has a strong amino acid sequence homology with visinin and recoverin (Terasawa, M., Nakano, A., Kobayashi, R., and Hidaka, H. J. Biol. Chem. In press). We produced antibody against neurocalcin. Immunoblotting showed the presence of neurocalcin in bovine retina as well as brain, suggesting that neurocalcin was a neuron specific Ca2+ binding protein. Immunohistochemistry revealed the expression of neurocalcin in retinal amacrine cells and ganglion cells but not in the photoreceptor layer. This distribution of neurocalcin was quite different from that of visinin and recoverin. Our results suggest that neurocalcin may play an important role in a Ca2+ signal pathway of the nervous system.


Propagation of a calcium pulse between osteoblastic cells. Using rat calvaria cells in primary culture monolayers and bone-like nodules, and isolated rat osteosarcoma cells, we show via laser scanning confocal microscopy and fluorescent indicator fluo-3/AM, that mechanical perturbation of a cell results in a transient increase (pulse) of measured intracellular calcium concentration that propagates from cell to cell, even between cells connected only by a thin process. The calcium pulse does not occur in the mechanically perturbed cell in calcium-free bathing medium, nor is there pulse propagation under this condition. Halothane, which blocks gap junctions, inhibits propagation. Propagation velocity does not decrease with successive cell to cell steps. These observations suggest the existence of a self-regenerating calcium signaling mechanism that may be based on a form of calcium-induced calcium release.


Reactive oxygen-reducing and protein-refolding activities of adult T cell leukemia-derived factor/human thioredoxin. Reducing and protein-refolding activities of adult T cell leukemia-derived factor (ADF)/human thioredoxin were studied. Recombinant ADF/human thioredoxin produced by E. coli, which has an insulin-reducing activity as efficient as that of E. coli thioredoxin, also reduced some reactive oxygen species, such as hydrogen peroxide. Furthermore, recombinant ADF/human thioredoxin was found to have protein-refolding activity for scrambled (mispaired disulfide-containing) RNase A. Cys-31 at the active site of ADF/human thioredoxin proved essential for reducing activity, and loss of Cys-31 in ADF/human thioredoxin attenuated the protein-refolding activity. These data suggest a physiological role of ADF/human thioredoxin in protecting living cells from proteotoxicity caused by reactive oxygens in vivo.


Evaluation of the holoenzyme content of aromatic L-amino acid decarboxylase in brain and liver tissues. We have re-evaluated the content of the holo-form of aromatic L-amino acid decarboxylase in rat tissues. Aromatic L-amino acid decarboxylase was found to consume pyridoxal 5'-phosphate while it underwent decarboxylation-dependent transamination as a side reaction. We observed that the total dopamine formation was proportional to the amount of holoenzyme. Dopamine formation in a tissue extract, which was preincubated with pyridoxal 5'-phosphate, was compared with the same tissue sample but which was prepared without preincubation. Percentages of holo-form of aromatic L-amino acid decarboxylase obtained from such comparison were 78% for brain and 94% for liver tissues. These values were significantly higher than those reported earlier in which the decarboxylation-dependent transamination of the decarboxylase had been overlooked.


Augmented expression of HSP72 protein in normal human fibroblasts irradiated with ultraviolet light. Normal human fibroblasts synthesized heat shock protein (HSP) 72 constitutively and its expression was augmented 6 hours after UV irradiation. Maximum induction of HSP72 was obtained at 12 hours and HSP72 showed a punctuated distribution in nucleus. While unscheduled DNA synthesis was almost completed 12 hours after UV irradiation, the S phase fraction decreased immediately and recovered after 6 hours. Thus, HSP72 augmentation was occurred coincidentally with the recovery of S phase, and suggested that HSP72 had some function during the recovery of DNA replication inhibited after UV irradiation.


The characterization of 5 histidine-serine mutants of human 5-lipoxygenase. The physical and catalytic properties of 5 histidine-serine mutants of human 5-lipoxygenase (5-LO) have been characterized. The mutants HS363, HS391 and HS400 have activities, pH optima and stabilities similar to those of the wild type enzyme. The iron content of each of these mutants is 0.30-0.53 mol Fe/mol 5-LO which is within the range observed for the wild type enzyme. HS368 contains iron (0.15 and 0.43 mol Fe/mol 5-LO in 2 preparations) but has no detectable oxygenase, leukotriene A4 synthase or anaerobic arachidonate-dependent hydroperoxidase activities. HS368 does have significant reducing agent-dependent hydroperoxidase activity suggesting that His-368 may not be an iron ligand but rather may be involved in interactions with arachidonic acid or the formation of the arachidonyl radical intermediate. HS373 contains no iron and has no detectable activities.


Construction of a tRNA-embedded-ribozyme trimming plasmid. We have combined Cotten and Birnstiel's tRNA-embedded ribozymes and our 5'- and 3'-trimming system. Although the activity of the tRNA-embedded ribozyme was ca. 30% lower than those of naked ribozymes, since the stability of the former in bovine serum was higher than those of naked ribozymes, the tRNA-embedded ribozymes appear useful especially when the 5'- and 3'-trimming units are concatenated in tandem.


Effects of a bone lysine-rich 18 kDa protein on osteoblast-like MC3T3-E1 cells. A lysine-rich 18 kDa protein was isolated from bovine bone and examined for its effects on osteoblast-like MC3T3-E1 cells. This protein is homologous to a heparin-binding protein in brain and uterus. This protein enhanced cell attachment independent of the Arg-Gly-Asp cell-binding sequence and stimulated proliferation during the growth phase. Addition of this protein to cell cultures on days 11, 12, and 13 after confluency resulted in a 1.6-2.0-fold increase in the alkaline phosphatase activity and little increase in the DNA content. These findings suggest that the 18 kDa protein may be functional in promoting the proliferation and differentiation of osteoblasts.


Effect of glycolipids on the phase behavior and dynamic properties of phospholipid liposomes. The glycolipids of Acholeplasma laidlawii AIH089 membranes were identified and purified. The effect of monoglucosyldiacylglycerol (MGDG) and diglucosyldiacylglycerol (DGDG) on the thermotropic behavior of multilamellar vesicles of dipalmitoylphosphatidylcholine (DPPC), dipalmitoylphosphatidylglycerol (DPPG) has been investigated by high sensitivity differential scanning calorimetry. The main transition peaks were broadened, the enthalpies were decreased. DGDG caused the decrease in the transition temperatures of DPPC, DPPG liposomes by 3.08 degrees C, 4.18 degrees C, respectively. MGDG did not cause the alteration of the transition temperature of DPPC liposomes but caused the decrease of the transition temperatures of DPPG liposomes by 2.20 degrees C. ESR experiments indicate that MGDG decreased the rotational correlation time of DPPC and DPPG liposomes.


4-Amino-6-methylhept-2-enoic acid: a leucine analogue and potential probe for localizing sites of proteolytic control in the hepatocyte. A recent analysis of leucine analogues has suggested that the carboxyl group is not required for mediating low concentration proteolytic inhibition in liver cells. In designing a probe to localize the regulatory site(s), we tested this hypothesis by synthesizing an analogue with a 2-carbon insert between the carboxyl and alpha-carbon. The Wittig product, a trans olefin, was fully active. Surprisingly, low concentration activity was lost when the double bond was eliminated by hydrogenation although some inhibitory effectiveness at high concentrations was evident. Since the double bond extends the carboxyl group away from the alpha-carbon, the results support the above hypothesis as well as the feasibility of adding functional groups to the carboxyl end of leucine.


Temperature-dependent protein folding in vivo--lower growth temperature increases yield of two genetic variants of Xenopus laevis Cu,Zn superoxide dismutase in Escherichia coli. Two genetic variants of Xenopus laevis Cu,Zn superoxide dismutase, XSODA and XSODB, have been expressed in Escherichia coli by recombinant DNA techniques. Production of both proteins was obtained, although with different yields, XSODB being more abundant than XSODA in all the conditions tested. Lowering the temperature of growth was found to be a specific factor, decisive in obtaining quantitatively abundant, active Xenopus enzymes. Impaired folding of these proteins in the E.coli cytoplasm was found to parallel their in vitro properties.


Nuclear proteins from Capan-2 cell line form specific complexes with the 17-1A antigen gene promoter. To determine the location of sites important for the function of the 17-1A antigen gene promoter and to characterize the protein factors binding to these sites, fragments of the promoter region were analysed by gel retardation assay with nuclear extracts from Capan 2 cell line. At least two separate regions, which specifically bind nuclear proteins, were identified within the 5'flanking region of the 17-1A antigen gene. These regions have been located between nucleotides -877 to -518 (distal region) and -193 to +3 (proximal region) and presumably participate in regulation of expression of the 17-1A antigen gene.


Heterotopic bone formation induced by bone morphogenetic protein in mice with collagen-induced arthritis. A study was conducted to investigate the influence of systemic inflammation on heterotopic bone formation induced by bone morphogenetic protein (BMP). Five-milligram pellets of BMP were implanted in mice with type II collagen-induced arthritis. Intraperitoneal injections of interleukin-1 (IL-1) were also administered to a group of mice without collagen-induced arthritis. The amount of BMP-induced heterotopic bone formation was evaluated by soft X-ray radiography, histology, and assay of calcium content. BMP-induced heterotopic bone formation was markedly enhanced in mice with collagen-induced arthritis, and also in IL-1-treated mice. These findings suggest that bone formation is enhanced in mice with collagen-induced arthritis, and that IL-1 may be responsible.


Phospholipid import into mitochondria: possible regulation mediated through lipid polymorphism. We previously demonstrated that the translocation of microsomal phosphatidylserine to the inner mitochondrial membrane occurs via contact sites before decarboxylation. According to the specific lipid composition of contact sites, we investigated lipid polymorphism as a possible regulation mechanism of phospholipid import into mitochondria. Phosphatidylserine import into mitochondria is increased in the presence of calcium, under conditions where non bilayer lipid-structures can be induced in cardiolipin-containing membranes. The results are discussed in terms of structural as well as functional domains heterogeneity within contact sites.


Expression of the B cell-associated tyrosine kinase gene Lyn in primary neuroblastoma tumours and its modulation during the differentiation of neuroblastoma cell lines. The src-related intracellular protein tyrosine kinase Lyn is a signal transducing molecule for surface immunoglobulin M and is expressed predominantly in hemopoietic cells. We report here the expression of the lyn gene in human neuroblastoma. In surgical tumour samples lyn transcripts were found preferentially at early stages whereas they were barely detectable in highly malignant tumours. In a cloned human neuroblastoma cell line, Be(2)C, lyn mRNA levels increased during neuronal differentiation induced by retinoic acid. Lyn mRNA levels were undetectable and did not respond to retinoic acid in a glial-type neuroblastoma clone, SH-EP. Retinoic acid-induced glial differentiation was associated with a reduction of lyn transcripts in a clonal I-type neuroblastoma cell line, SH-IN, which shares properties of both neuronal- and glial-type clones. Like pp60c-src Lyn may be involved in a signalling pathway of neuroblasts committed to neuronal differentiation.


Induction of platelet-derived growth factor chain A gene expression in human smooth muscle cells by oxidized low density lipoproteins. Abnormal proliferation of vascular smooth muscle cells is a key event in the formation of atherosclerotic plaques in humans. It has been suggested that modulation of platelet derived growth factor chain A (PDGF-A) gene expression may contribute to atherosclerosis. Using an 'in situ hybridization' technique the present study shows that the presence of low density lipoproteins induces an eight fold increased expression of the transforming gene PDGF-A in human smooth muscle cells. The influence on PDGF-A expression only occurred after oxidative modification of low density lipoproteins, a process known to be important in atherogenesis. The non-atherogenic high density lipoproteins did not modulate the PDGF-A mRNA levels in smooth muscle cells. Consequently, oxidized low density lipoproteins may participate in atherosclerotic lesion formation as a result of autocrine stimulation of PDGF-A.


Interaction of DNA with cationic liposomes: ability of transfecting lentil protoplasts. The vesicle made of dipalmitoylphosphatidylcholine and stearylamine (9:1) were multilamellar and rather homogeneous in shape as seen by transmission electron microscopy. Upon addition of circular DNA plasmids of different lengths to the liposomes, the formation of vesicle clusters around the DNA filament was observed, with dimensions dictated by the ratio DNA/lipid. These liposomes were able to transfect lentil (Lens culinaris) protoplasts inside the cells two different reporter genes, chloramphenicol-acetyltransferase and beta-glucuronidase. The activity of these two enzymes could be found in the cell lysates after 24 h from the incubation of protoplasts with the lipid-DNA complexes.


Microbial oxidation of adamantanone by Pseudomonas putida carrying the camphor catabolic plasmid. Intact cells of (+/-)camphor-grown Pseudomonas putida, ATCC17453(CAM), have been shown to oxidize readily the monoketone derivative of cage hydrocarbon adamantane, forming oxygenated products indicative of both biological Baeyer-Villiger and hydroxylation reactions. Formed products were identified as 4-oxahomoadamantan-5-one, 5-hydroxyadamantan-2-one and 1-hydroxy-4-oxahomoadamantan-5-one. Minor products formed as a result of secondary reactions were tentatively identified as syn- and anti-1,4-dihydroxyadamantanes and bicyclo[3.3.1]nonan-3-ol. Adamantanone initial concentrations determined whether 1-hydroxy-4-oxahomoadamantan-5-one was the sole product (below 120 mg/l) or 4-oxahomoadamantan-5-one was the principle (up to 92%) product (240-600 mg/l). Formation of 1-hydroxy-4-oxahomoadamantan-5-one appears to occur by two routes determined by the sequence of lactonization and hydroxylation.


Development of hydrophobicity parameters for prenylated proteins. We have determined hydrophobicity parameters for the side-chains of the prenyl thioether protein modifications, farnesyl-cysteine and geranylgeranyl-cysteine. Farnesyl-Cys is somewhat more hydrophobic than palmitoyl-Cys, but geranylgeranyl-Cys is more than two log(P) units more non-polar. These post-translational modifications represent the most hydrophobic residues yet described quantitatively. Furthermore, such modifications occur at the COOH-terminus which is generally methyl esterified. Loss of the terminal negative charge and formation of the ester proceeds with the gain of an additional 2.343 log(P) units of hydrophobicity. Clearly, COOH-terminal prenylation and esterification impart sufficient potential to render the terminus membrane bound. Thus, hydrophobicity parameters presented here for the prenylated amino acyl residues extend our understanding of these important physiological derivatives and enable computational analysis of proteins thus modified.


Age-associated decreases in prostaglandin contents in human gastric mucosa. This study was designed to clarify effects of ageing on human gastric mucosal prostaglandin (PG) contents. Forty examinees were divided into 5 age groups of 8 persons each, as follows: age under 40, age 40-49, age 50-59, age 60-69, and age over 70. PG contents in human gastric mucosa were measured by microcolumn high performance liquid chromatography (HPLC) with helium/cadmium laser induced fluorescence detection using biopsy samples obtained by endoscopy. The contents of 6-keto-PGF1 alpha, PGF2 alpha, PGE2, and PGD2 in the under 40 group were 638 +/- 39, 97 +/- 16, 468 +/- 68, 497 +/- 86 (pg/mg tissue), respectively. No significant differences in PG contents among groups aged under 70 were observed. In contrast, significantly low PG contents in the over 70 group were observed, i.e., the contents of 6-keto-PGF1 alpha, PGF2 alpha, PGE2, and PGD2 were 311 +/- 58, 36 +/- 8, 196 +/- 48, 171 +/- 40, respectively, and their contents were significantly lower than those in other age groups. In conclusion, gastric mucosal PG contents decrease significantly in over 70 years-old and this might be a contributing factor in the pathogenesis of gastric ulcers in elderly people.


Genes for bone morphogenetic proteins are differentially transcribed in early amphibian embryos. We have previously demonstrated that activin, a member of the TGF-beta family, has a potent mesoderm-inducing activity in Xenopus embryos. In the course of screening for activin-related genes from Xenopus, we have cloned cDNAs for Xenopus homologue of BMP-2, -4 and -7. Northern blot analysis revealed that these BMP genes are maternally encoded and differentially regulated after fertilization. Alkaline phosphatase-inducing assay using the recombinant BMP proteins has shown that at least BMP-2 and -4 have similar activity to mammalian counterparts.


Sensitive detection and identification of mycoplasma-like organisms in plants by polymerase chain reactions. DNA amplification by polymerase chain reactions (PCR) was employed to detect host plant infection by several mycoplasmalike organisms (MLOs), including the aster yellows (AY), dwarf aster yellows (DAY), and periwinkle little leaf (0-1) MLOs. For PCR, two pairs of oligonucleotide primers, designated AY18pm and AY19pm, respectively, were synthesized on the basis of partial sequences of cloned AY MLO DNA fragments AY18 and AY19. Reaction mixtures containing primer pair AY18pm yielded a DNA product of 1.6Kbp, when template consisted of DNA extracted from AY MLO- or DAY MLO-infected Catharanthus roseus (periwinkle). A DNA product of 1.0Kbp was obtained with primer pair AY19pm, when template consisted of DNA extracted from C. roseus infected by AY MLO, DAY MLO, or periwinkle little leaf (strain O-1) MLO. MLO-specific bands were observed when reaction mixtures contained as little as 5 pg total nucleic acid from infected plants. No PCR product was observed when reaction mixtures contained only DNA from healthy plants or DNA from plants infected by western X MLO or by tomato big bud MLO. The findings indicated that the PCR system is useful for sensitive detection and differentiation of MLOs in infected hosts.


PDGF AA homodimers are potent chemoattractants for fibroblasts and neutrophils, and for monocytes activated by lymphocytes or cytokines. The A-chain homodimers of the platelet-derived growth factor (PDGF AA) are widely expressed in normal and transformed cells. The mitogenic properties of PDGF AA are well established; however, the chemotactic potential of PDGF AA remains controversial. We now show that PDGF AA is a strong chemoattractant for human monocytes, granulocytes, and fetal bovine ligament fibroblasts. However, highly purified (greater than 98%) monocytes require the addition of lymphocytes or IL-1 for chemotactic responsiveness to PDGF AA but not for full chemotactic activity with formyl-methionyl-leucyl-phenylalanine (fMLP) or C5a. These results indicate that PDGF AA is a potent chemoattractant. These results also indicate that monocytes require activation either by lymphocytes or exogenous cytokines in order to respond chemotactically to PDGF AA but not to fMLP or C5a and suggest roles of the lymphocyte and cytokine in the chemotactic response of the monocyte to PDGF AA in vivo.


Methylation inhibits the interaction of DNA binding proteins with a potential c-abl intron regulatory element. We have identified DNA binding proteins which interact with a sequence found in an intron of the tyrosine kinase coding portion of the murine c-abl gene. Several specific DNA: protein complexes were observed. Those complexes of approximate molecular weights 64 and 66kDa were detected when an Msp I site (CCGG) within the sequence was unmethylated, but were not observed when that site was methylated. Insertion of the intron sequence 5' to the rat somatic cytochrome C promoter and chloramphenicol acetyl transferase (CAT) sequences resulted in at least four-fold stimulation of CAT activity. These data suggest a potential role for the intron sequence in the regulation of gene expression.


Isolation and structural characterization of a new crosslinking amino acid, cyclopentenosine, from the acid hydrolysate of elastin. A novel polyfunctional crosslinking amino acid, which was developed slower than lysinonorleucine and faster than desmosine on thin layer chromatography, was isolated from the hydrolysate of bovine aorta elastin. Its proposed structure was verified by ultraviolet spectroscopy, fast atom bombardment mass spectroscopy, and nuclear magnetic resonance spectroscopy. The data indicated it to be a trifunctional amino acid with a cyclopentene structure. The mass spectral analysis indicated a parent compound with a mass of 381 (C18H27N3O6). The proposed structure is one derived from the condensation of three allysine residues. Based on the names of other crosslinking amino acids found in elastin, the trivial name of cyclopentenosine is given to this compound.


SK&F 96365 inhibits histamine-induced formation of endothelium-derived relaxing factor in human endothelial cells. Formation of endothelium-derived relaxing factor (EDRF) strictly correlates with the intracellular free Ca2+ ([Ca2+]i) concentration. We now demonstrate that the histamine-induced rise in [Ca2+]i of human umbilical vein endothelial cells is mostly due to activation of a membrane current which allows Ca2+ entry. This membrane current is sensitive to the novel inhibitor of agonist-induced Ca2+ entry, SK&F 96365, which blocked the histamine-induced sustained rise in [Ca2+]i, as well as 45Ca2+ uptake and membrane currents. Inhibition of the above cellular responses to histamine was accompanied by a considerable reduction of EDRF formation and release. Thus biosynthesis and release of EDRF from human umbilical vein endothelial cells significantly depend on agonist-induced Ca2+ entry involving receptor-operated Ca(2+)-permeable channels which can be blocked by SK&F 96365.