Expression of the 64 kDa/glutamic acid decarboxylase rat islet cell autoantigen is influenced by the rate of insulin secretion. This study examined the relationship between insulin secretion and expression of the 64 kDa/glutamic acid decarboxylase autoantigen in pancreatic islets. Islets isolated from Wistar rats were cultured for 3 days under different conditions: in 5.5 mmol/l glucose with or without alpha-ketoisocaproic acid or glipizide and in 28 mmol/l glucose with or without diazoxide. The 64 kDa/glutamic acid decarboxylase autoantigen was precipitated from lysates of [35S]-methionine-labelled islets with sera from patients with Type 1 (insulin-dependent) diabetes mellitus and identified by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and fluorography. In parallel, insulin contents of the islets and the media were determined as well as the rates of glucose-stimulated (pro)insulin biosynthesis. alpha-Ketoisocaproic acid and glipizide were found to stimulate the expression of the 64 kDa/glutamic acid decarboxylase autoantigen and also the rate of insulin secretion. Diazoxide on the other hand reduced the rate of the 64 kDa/glutamic acid decarboxylase autoantigen synthesis in parallel with an inhibition of glucose-stimulated insulin release. Under most of the conditions employed, (pro)insulin biosynthesis was not affected. The correlation found between the rate of insulin release and expression of the 64 kDa/glutamic acid decarboxylase autoantigen might provide an explanation for the earlier observed relationship between the functional demands on the Beta cells and their rate of destruction which may result in diabetes.


Control, bioenergetics, and adaptation in health and disease: noninvasive biochemistry from nuclear magnetic resonance. The noninvasive study of cellular homeostasis, control, and energetics in tissues and organs within intact living systems is now possible. Nuclear magnetic resonance (NMR) spectroscopy in vivo provides information about key metabolites, reaction rates, the control of ionic equilibria and fluxes (including that of H+), and molecular diffusion and motions within the cell. When phosphorus (31P) is measured, the processes associated with the production and utilization of adenosine triphosphate (ATP) are followed. Using 13C for measurement, the pathways and fluxes in the synthesis and degradation of sugars (e.g., glycogen), amino acids, etc., can be observed. Intracellular, cytoplasmic pH (H+ concentration) can be determined from the 31P-NMR spectrum of organs and cells whereas Na+ and K+ (or its congener Rb+) are directly measurable by NMR. All these can be observed in physiological situations in almost any organism in the animal or plant kingdom. The bioenergetics of locust muscle in flight is as readily measured as that in human muscle in health, training, and disease. When spatially resolved, the NMR spectra can provide metabolic maps of the human heart, brain, and other organs. Thus we can now directly delineate the biochemical basis of human diseases.


Studies of intestinal stem cells using normal, chimeric, and transgenic mice. The mouse intestinal epithelium represents a continuous developmental system. Its four principal differentiated cell types--enterocytes, goblet, enteroendocrine, and Paneth cells--are derived from a common multipotent stem cell located near the base of monoclonal crypts. Members of these four lineages undergo rapid and perpetual renewal along an anatomically well-defined pathway. The gut epithelium provides a unique mammalian model for studying the biological features of stem cells (e.g., their ability to undergo asymmetric division, their enormous proliferative potential, their capacity for functional anchorage in a niche), examining how stem cell hierarchies are established and maintained in renewing cell populations, analyzing the relationships between passage through the cell cycle and lineage allocation (commitment), and defining the mechanisms that give stem cells a "positional address" along the cephalocaudal axis, allowing them to generate regional differences in the differentiation programs of their derived lineages (axial pattern formation).


Function of the c-Myc oncoprotein.

Function of the c-Myc oncoprotein. The c-Myc protein, the product of the c-myc proto-oncogene, is a nuclear phosphoprotein with DNA binding properties. Deregulated c-myc expression participates in the development of experimentally induced tumors, and its expression appears to be abnormal in many naturally occurring malignancies. Although the precise molecular mechanism of c-Myc activity in oncogenesis and in normal cell proliferation is unknown, recent advances have uncovered a series of molecular and cellular properties of c-Myc. These properties include nuclear localization, transcriptional activation, oligomerization nonspecific and specific DNA binding. Recently, the c-Myc protein was found to heterodimerize with Max, a protein that cooperates with c-Myc to bind specifically to a core DNA sequence, CAC(G/A)TG. These characteristics suggest that c-Myc participates in the regulation of gene transcription in normal and neoplastic cells.


Electrolyte transport in the epithelium of pulmonary segments of normal and cystic fibrosis lung. The epithelium of pulmonary segments from trachea to aveoli actively transports electrolytes and allows osmotic movement of water to maintain the ionic environment in the airway lumen. Models of airway absorption and secretion depict the operation of transporters localized to apical or basolateral membrane. In many epithelia, a variety of electrolyte transporters operate in different combinations to produce absorption or secretion. This also applies to pulmonary epithelium of the large airways (trachea, main-stem bronchi), bronchioles, and alveoli. Na+ absorption occurs in all three pulmonary segments but by different transporters: apical Na+ channels in large airways and bronchioles; Na+/H+ exchange and Na+ channels in adult alveoli. The Na+ channels in each pulmonary segment share a sensitivity to amiloride, a potent inhibitory of epithelial Na+ channels. Fetal alveoli display spontaneous Cl- secretion, as do the large airways of some mammals, such as dog and bovine trachea. Cl- channels differ in conductance properties and in regulation by intracellular second messengers, osmolarity, and voltage mediate stimulated Cl- secretion. Electroneutral carriers, such as NaCl(K) cotransport, Cl-/HCO3- exchange, and Na+/HCO3- exchange, operate in large airways and alveoli during absorption and secretion. Abnormal ion transport in airways of cystic fibrosis (CF) patients is manifest as a reduced Cl- conductance and increased Na+ conductance. Isolation of the CF gene and identification of its product CFTR now allow investigations into the basic defect. Intrinsic to these investigations is the development of systems to study the function of CFTR and its relation to electrolyte transporters and their regulation.


Elevation of lung glutathione by oral supplementation of L-2-oxothiazolidine-4-carboxylate protects against oxygen toxicity in protein-energy malnourished rats. The objectives of this study were to investigate whether oral supplementation of L-2-oxothiazolidine-4-carboxylate (OTC) is effective for increasing tissue glutathione (GSH) concentrations in rats fed a diet very low (0.5%) in protein-a model of wasting malnutrition-and to determine the efficacy of OTC for protection against pulmonary oxygen toxicity. Weanling rats, fed a 0.5 or 15% protein diet for 2 wk, were given an oral supplement of OTC, and tissue GSH concentrations were measured over a 24 h period. OTC supplementation to rats fed 0.5% protein significantly increased GSH concentrations in liver and lung, but not in kidney and blood, when compared with the 0.5% protein unsupplemented group. The liver GSH concentration in the 0.5% protein OTC-supplemented group was higher than the 15% control group. Daily supplementation of OTC protected rats from pulmonary oxygen toxicity during 4 days of 85% oxygen exposure as determined by lung-to-body weight ratios and in vivo proton magnetic resonance imaging. Although hyperoxia exposure increased lung GSH concentrations in all groups, OTC supplementation was effective for increasing lung GSH concentration in rats fed the 0.5% protein diet. This study demonstrated that oral administration of OTC to wasting malnourished rats is an effective procedure to increase GSH concentration rapidly in target organs such as lung, and that daily supplementation of a low dose of OTC has a sustained effect to protect against pulmonary oxygen toxicity during 4 days of hyperoxia exposure.


A parkinsonian syndrome induced in the goldfish by the neurotoxin MPTP. Parkinson's disease has been modeled in humans, lower primates, and to a lesser extent in some other vertebrates by administration of the potent neurotoxin MPTP (1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine). The MPTP model has thus drawn considerable attention as a system to search for anti-Parkinson's disease drugs, although the cost and scarcity of primates has limited extensive applications. We now report that a parkinsonian syndrome can be elicited in the common goldfish (Carassius auratus) by a single dose of MPTP. The syndrome is characterized by profound bradykinesia (slow movement), the full extent of which is reached 3 days after MPTP administration. The reduction in movement is paralleled by loss of dopamine and norepinephrine from the forebrain and midbrain and in other brain regions as well. The toxic oxidative product of MPTP, MPP+, is also accumulated predominantly in forebrain and midbrain, and pretreatment with the monoamine oxidase blocker tranylcypromine substantially reduces accumulation of the toxic metabolite. A barely perceptible coarseness in balance adjustment also occurs in treated animals. The MPTP-treated goldfish recover normal movement and normal brain monoamine levels within 10-13 days after administration of the drug. We interpret these and other data to indicate that MPTP can induce a Parkinson's disease-like syndrome in the goldfish that is similar in many aspects to the syndrome induced by MPTP in humans and other primates. This remarkable parallel may permit the goldfish to supplement expensive and scarce primates for the purpose of searching and screening neuroprotective drugs with specific relevance to Parkinson's disease.


Culture of bovine pulmonary artery endothelial cells on Gelfoam blocks. Conventional methods of endothelial cell culture on monolayers and beads require enzymatic digestion, traumatic scraping, or centrifugation to transfer cells to other experimental systems. Gelfoam, a porous gelatin block, not only supports the growth of bovine pulmonary artery endothelial cells but also allows the rapid transfer of cell-laden blocks from one experimental system to another with minimal intervention. This property has been shown to be especially useful for the rapid fixation of endothelial cells for microscopy using standard histologic methods. Histology confirmed that the trabecular nature of the substrate allows endothelial cells to line the interstices of the sponge matrix and grow in a configuration that simulates the appearance of the endothelium in small vessels and capillaries. The inoculation of 1 x 10(5) endothelial cells on 7.5 mg Gelfoam (24 x 8 x 2 mm blocks) was enhanced by fibroblast growth factor and resulted in cell attachment by day 2 with a cell doubling time of 1.7 days. In addition, endothelial cells completely infiltrated 1, 5 and 7.5 mg Gelfoam blocks, as verified by histology. Assays to quantify cell number and protein were easily performed. To facilitate cell counting, the Gelfoam matrix was rapidly removed by the addition of 0.05 mg/ml collagenase, a concentration that interfered minimally with the assay for cellular protein concentration. The data demonstrate that Gelfoam is a suitable support growth matrix for the in vitro culture of bovine pulmonary artery endothelial cells.


[Thyroid function tests in healthy and ill elderly]. Thyroid function in the elderly has been a matter of discussion. The universe of the present study includes males and females 36 hospitalized with an average age of 72.97 +/- 8.70 years (group I) and 36 ambulatory asymptomatic elderly with 69.81 +/- 8.55 years of age (group II). Serum levels of T3, T4, T4L and TSH were measured in both groups. Mean values of T3 were significantly lower in the hospitalized patients than in the control group. The difference persisted on both, males and females, analyzed separately. Mean values of T4L were significantly lower in women of group II, while mean values of T3 were significantly lower in men of group I. The comparison of thyroid function tests in male and female showed that serum values of T3 and T4 were significantly lower in men of group I. By dividing results in age categories, serum levels of T4L in group II were significantly lower in the age group of 70 to 79 and 80 to 89. Thyroid function tests in asymptomatic ambulatory elderly tend to be normal, whereas the hospitalized patients showed a high proportion of alterations.


[Histologic changes in peptic disease].

[Histologic changes in peptic disease]. The purpose of this work is to describe pathological alterations produced by the gastric juice in esophagus, stomach, duodenum, and small intestine. Histology of these segments of the gastrointestinal tract are briefly explained. Peptic esophagitis, Barrett's esophagus, chronic gastritis, duodenitis, and peptic ulcer in several sites are described.


[Usefulness of ultrasonography in the complications of hepatic punction. Prospective studies]. We evaluated the usefulness of ultrasonography (US) to detect hepatic puncture complications. We studied 50 patients, 28 males and 22 females became hepatic puncture. The needles that we used were in 40 Tru-cut in two Chiba in one angiocath and in the other remaining two. US were performed one day before the liver puncture and were repeated 24 to 48 h post-puncture. The procedure was blindly on 29, in fourteen guided by US or scintigraphy, and by laparoscopy in seven. Six patients developed complications (12%), two hemobilia; two subcapsular hematoma, one hemoperitoneum and one hematoma of the abdominal wall. The US detected five of the six complications, and four patients had clinical signs. The sensitivity was 88 percent and the specificity 100%. Platelet count impaired was determinant for the complication. US is useful to detect liver puncture complications.


The detection of two antigenic groups among Renibacterium salmoninarum isolates. The analysis of the membrane proteins and their antigenic properties in a group of 14 geographically diverse strains of Renibacterium salmoninarum revealed the existence of antigenic diversity within this species. Eleven isolates, including the type strain ATCC 33209, shared a similar protein profile with a major component of 57 kDa whereas three strains showed a common pattern with a major protein of 30 kDa. The quantitative agglutination tests and Western blotting assays seem to indicate the existence of serological heterogeneity, with two distinct groups being detected.


[Rheumatic features of Grave's disease in children]. We report three cases from girls with Graves disease who developed serious rheumatic manifestations. One patient had systemic lupus erythematosus with articular, renal, neurological and cardiac afectation with fatal outcome. Other patient presented clinical features of scleroderma with skin thickness, myopathy, arthritis, Raynaud's phenomenon and findings of pulmonary fibrosis. A lupus-like syndrome associated to methimazole therapy (polyarthritis, rash and hemolytic anemia) with positive Cel-LE preparations but negative antinuclear-antibodies was observed in a third patient. A careful history and the recognition of these manifestations will help in the identification of these syndromes.


Two forms of ribulose-1,5-bisphosphate carboxylase/oxygenase from Thiobacillus denitrificans. The autotrophic, sulfur-oxidizing bacterium Thiobacillus denitrificans possesses two forms of the Calvin cycle enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO). The form I and form II genes were isolated from a cosmid library using heterologous DNA probes. Restriction enzyme analysis indicated that the genes are within 17 kbp of each other. Other Calvin cycle enzyme genes are not present. Analysis of T. denitrificans RNA indicated that the form I genes for the large and small subunits are co-transcribed with a length of 2800 nucleotides. The transcript for the form II gene is 1900 nucleotides in length.


Characterization of an extracellular factor that stimulates bile salt hydrolase activity in Lactobacillus sp. strain 100-100. Bile salt hydrolase activity in Lactobacillus sp. strain 100-100 is strictly intracellular. The strain produces an extracellular factor that stimulates the intracellular hydrolase activity. The factor is inducible by conjugated bile salts, has an apparent molecular mass over 12 kDa but less than 25 kDa, is stable in air, and resistant to pronase and heat. It is partially extractable into organic solvents and inactivated by a sulphydryl group inhibitor. We postulate that the factor functions by a novel mechanism to facilitate entry of conjugated bile salts into the bacterial cells.


Stage-specific proteinases of Leishmania mexicana mexicana promastigotes. Four distinct bands of cysteine proteinase activity were detected when stationary-phase populations of Leishmania mexicana mexicana were subjected to gelatin-SDS-PAGE. The highest mobility band contained at least three isoforms separable by mono Q anion exchange chromatography. These high mobility activities were distinct from all the major amastigote enzymes. Stationary-phase promastigote populations also contained two acid-activable precursor forms of the promastigote-specific band. It is suggested that these promastigote-specific activities occur in the infective metacyclic stage of the parasite and may have a role in parasite survival upon inoculation into a mammal.


[The influence of psychosocial deprivation and body composition on plasma gonadotrophins in children and adolescents]. The plasma concentrations of FSH and LH were measured in 250 boys with psychosocial deprivation (PSD) aged 9.0-15.9 years and in 357 clinically healthy boys of the same age. The results were correlated with chronological age (CA), weight, height and calculated lean body mass (LBM) and total body fat (TBT). On a group basis, PSD boys had the clinical onset of puberty at 13.9 years, while healthy boys did so at 11.9 years. In both groups, the mean weights at time of initiation of the adolescent growth spurt and time of peak velocity of weight gain were very close to each other and the same phenomenon was true for their heights and the amount of LBM. Based on CA mean plasma FSH concentrations in PSD boys and a steep rise two years later than in healthy boys; however, when analyzed as a function of body weight, height or LBM, no such difference emerged. On the other hand, mean plasma LH concentrations in PSD boys were higher than in healthy boys only up to 12.9 years, 42.9 kg of body weight, a height of 142.0 cms and LBM of 32.0 kg; however, no steep rise in plasma LH was observed in contrast to healthy boys. No correlations was observed between TBF and plasma gonadotropins. Therefore, although on the basis of CA, PSD boys had a delayed onset in plasma gonadotropins changes, this occurred in association with the attainment of similar body weight, height and LBM as in healthy boys.(ABSTRACT TRUNCATED AT 250 WORDS)


Improved method for electroporation of Staphylococcus aureus. We have developed a significantly improved method for the electroporation of plasmid DNA into Staphylococcus aureus. The highest transformation efficiency achieved with this procedure was 4.0 x 10(8) transformants per microgram of plasmid pSK265 DNA. This represents a 530-fold improvement over the previously reported optimum efficiency of 7.5 x 10(5) transformants per microgram of plasmid DNA after electroporation of S. aureus cells [9]. Identical results were obtained when electrocompetent cells, which had been stored frozen at -80 degrees C, were used. The improved efficiency is due primarily to the use of a modified medium (designated as B2 medium) and secondarily to the use of 0.1-cm cuvettes. Several other plasmids (pI258, pMH109, and pSK270) were also electrotransformed into competent cells using our procedure, and for each plasmid, the transformation efficiency was significantly reduced compared to that observed when pSK265 DNA was used. With respect to plasmid pI258, the transformation efficiency was 3500-fold higher than that reported previously for transformation of this plasmid into S. aureus RN4220 [9]. The optimized electroporation procedure was less successful in transforming other staphylococci. Electrocompetent cells of S. aureus ATCC 29213 and S. epidermidis ATCC 12228 produced 5.5 x 10(5) and 5 x 10(3) transformants per microgram of pSK265 DNA, respectively.


PCR amplification of streptococcal DNA using crude cell lysates. Gram-positive organisms such as streptococci and enterococci are often difficult to lyse. Obtaining DNA for procedures such as PCR amplification usually requires a large scale isolation for each strain under investigation. We describe a simple procedure for small volumes of whole cells, involving pretreatment with detergent and proteinase that allows for efficient release of DNA for PCR amplification. This procedure is fast, reproducible, can be used with a large number of samples, and has been successfully applied to a variety of streptococcal and enterococcal strains.


Transcription of glpT of Escherichia coli K12 is regulated by anaerobiosis and fnr. The transcriptional expression of the sn-glycerol 3-phosphate transport gene, glpT, was studied with a glpT-lac fusion contained on a low-copy-number plasmid pFZY1. The fusion was isolated during a 'shot gun' cloning of promoters expressed under anaerobic growth conditions. It was shown that glpT was induced six-fold by anaerobiosis. Furthermore, aerobic expression of glpT was induced by the substrate glycerol 3-phosphate, while the anaerobic expression of glpT was decreased by nitrate, glucose and a fnr mutation. However, nitrate repression on glpT expression was relieved if the upstream region from -290 of the transcription site was removed.


Sequential inactivation of ammonium and glucose transport in Saccharomyces cerevisiae during fermentation. Ethanol at concentrations above 12% (v/v) in mineral medium with glucose and with ammonium as the only nitrogen source induced rapid inactivation of the ammonium transport system in the strain IGC 3507 of Saccharomyces cerevisiae terminating protein synthesis. Subsequently, when glucose was present, the glucose transport system was irreversibly inactivated. This two-step mechanism may play a decisive role when ethanol stops fermentation by S. cerevisiae, before all the fermentable sugar has been consumed.


Cloning of a Clostridium thermocellum DNA fragment encoding polypeptides that bind the catalytic components of the cellulosome. A test based on the binding of 125I-labelled endoglucanase CelD was used to clone a DNA region encoding at least two different polypeptides that interact with the conserved reiterated segment present in many catalytic components of the Clostridium thermocellum cellulosome. One of the polypeptides corresponds to the COOH-terminal region of the SL (or S1) component of the cellulosome (U.T. Gerngross and A.L. Demain, personal communication). It comprises repeated domains that are responsible for binding 125I-labelled CelD, and presumably represent anchoring sites for the various catalytic components of the cellulosome. The other polypeptide is encoded by a gene that has not yet been described.


Differentiation of polyphosphate and poly-beta-hydroxybutyrate granules in an Acinetobacter sp. isolated from activated sludge. Cells containing polyphosphate 71 micrograms P (mg protein)-1 and no poly-beta-hydroxybutyrate showed metachromatic granules but no lipid granules; cells containing poly-beta-hydroxybutyrate (15% of dry weight) showed fluorescence lipid granules but no metachromatic granules; whereas cells containing both polyphosphate and poly-beta-hydroxybutyrate showed both types of granules. These observations, together with a critical review of the literature, show a clear distinction between metachromatic (or volutin) granules and lipid granules.


Sequence and characterization of the gcpE gene of Escherichia coli. In Escherichia coli, the gene gcpE encodes a protein of unknown function and lies immediately upstream of the hisS gene for histidyl-tRNA synthetase. The nucleic acid sequence of gcpE predicts an open reading frame for a protein of 40,681 Da. The probable transcription terminator of gcpE overlaps the hisS promoter. Haploid cells containing a disrupted gcpE could not be obtained, suggesting that the gcpE gene is essential.


An extracellular enzyme from Fusarium solani f. sp. phaseoli which catalyses hydration of the isoflavonoid phytoalexin, phaseollidin. Among the antimicrobial phytoalexins produced by Phaseolus vulgaris (French bean) are the prenylated isoflavonoids kievitone and phaseollidin. Two enzyme activities, kievitone hydratase and phaseollidin hydratase, occur in culture filtrates of the bean pathogen, Fusarium solani f. sp. phaseoli, and catalyse similar hydration reactions on the dimethylallyl moieties of the phytoalexins. The enzymes nearly co-purified during hydroxyapatite chromatography followed by preparative native gel electrophoresis. Eluates from successive slices taken from the native gel were assayed for both activities. Although they were not completely separated in the native gel, the activity profiles indicated that the two activities were distinct. The Km of phaseollidin hydratase for phaseollidin was approximately 7 microM.


Evidence for the existence of a restriction-modification system common to several species of the family Vibrionaceae. A broad-host-range vibriophage KVP40 originally isolated on Vibrio parahaemolyticus 1010 was restricted and modified by strains of at least five Vibrio and one Photobacterium species. 1010 was a non-restricting host. An anti-restriction mutant KVP40 aar1 was isolated after propagating the phage on a restricting host, V. anguillarum VIB36. KVP40 aar1 grown on either 1010 or VIB36, as well as the parental phage grown on VIB36, showed much higher efficiencies of plating on all the restricting hosts as compared with the parental phage grown on 1010, indicating that these restricting hosts probably share a common restriction-modification system active in vivo on KVP40.


Modified peptidoglycan precursors produced by glycopeptide-resistant enterococci. Cytoplasmic precursors of the peptidoglycan biosynthetic pathway were purified from vancomycin-treated, glycopeptide-sensitive and -resistant strains of Enterococcus faecium. Resistance was due to production of a modified precursor, UDP-MurNAc-L-Ala-D-Glu-L-Lys-D-Ala-D-lactate, where lactate was identified on the basis of mass of the precursor and on its ability to act as a substrate for D-lactate dehydrogenase after release from the precursor. The presence of the D-lactate residue instead of D-alanine in the terminal position would hinder formation of a vancomycin-precursor complex, without preventing incorporation of the precursor into mature peptidoglycan.


Molecular monitoring of the transcriptional activation of the yeast Saccharomyces kluyveri mating pheromone signal transduction by using FUS1-lacZ fusion gene. To analyse the molecular mechanism by which a mating pheromone signal is transmitted in Saccharomyces kluyveri, the S. cerevisiae FUS1-lacZ fusion gene was introduced into S. kluyveri cells and its transcriptional activation was investigated. The expression of FUS1-lacZ fusion product was cell-type-specifically induced by pheromone treatment in S. kluyveri. The result suggests that S. kluyveri pheromone signal may be transduced by a mechanism similar to that in S. cerevisiae. This system may provide a model for analysing the molecular mechanism of the mating reaction in Saccharomyces kluyveri.


The role of Eh, pH and iron in the bactericidal power of human plasma. The bactericidal power of fresh human plasma against Klebsiella pneumoniae and Escherichia coli was extremely sensitive to changes in Eh and pH. At a high Eh (approx. +200 mV) the bacteria were destroyed, but rapid regrowth occurred when the Eh was lowered to approx. -400 mV. Abolition of the bactericidal effect was also produced by adding ferric iron at a high Eh (approx. +200 mV). Lowering the pH to 6.50 reduced or prevented the bactericidal effect. These results are probably related to the availability of iron for bacterial growth, and could be important for understanding the development of infection in injured or diseased tissue.


pH track of expanding bacterial populations. A method of pH distribution measurements in agar nutrient media containing expanding bacterial populations is described. It is based on measuring pH microsamples taken at different points of the media. The sample volume was 10 microliters. A pH sensitive field effect transistor was used as a measuring electrode. Acidification was found to occur in glucose media, while alkalization occurred in the media containing peptone.


Comparative evaluation of the metabolic potentials of different strains of Peptostreptococcus productus: utilization and transformation of aromatic compounds. Three strains of Peptostreptococcus productus were tested for growth at the expense of methoxylated aromatic compounds. Strain M8A-18 (human fecal isolate) was unable to utilize methoxylated aromatic compounds. While the type strain ATCC 27340 (human septicemia isolate) was capable of minimal growth with methoxylated aromatic compounds, ATCC 35244 (sewage sludge isolate) displayed significant growth on methoxylated aromatic compounds. Methoxylated phenols, benzoates, benzyl alcohol and phenylacrylates supported the growth of ATCC 35244 and were O-demethylated to their respective hydroxylated derivatives. During O-methyl- or CO-dependent growth, the double bond of the acrylate side chain of certain methoxylated and non-methoxylated phenylacrylates was reduced. Although other aromatic substituent groups (-COOH and -CH3) were transformed during CO-dependent growth, in short-term growth studies, the aromatic ring was not subject to reduction or degradation. Of the three strains tested, only strain M8A-18 failed to grow at the expense of carbon monoxide (CO).


The location of the arginine-specific carboxypeptidase in the membrane of Mycoplasma salivarium and its physiological functions. A non-penetrating probe, 2,4,6-trinitrobenzenesulfonate, inhibited the activity of the carboxypeptidase purified from the cell membranes of Mycoplasma salivarium and the same enzymatic activity of intact Mycoplasma cells as well. Growth of the organism in medium containing benzoylglycyl-L-arginine resulted in a higher pH and higher turbidity than growth in the same medium without this supplement. It was concluded that the enzyme existed in the outer surface of the membrane of the cells and probably functioned to supply the organism with arginine as an energy source.


Production of monovalent antisera by induction of immunological tolerance for capsular typing of Streptococcus pneumoniae. Hyperimmune and high-titered polyclonal pneumococcal antisera, specific for cross-reactive types within groups, were produced in adult rabbits. Purified capsular polysaccharide was injected intravenously into adult rabbits. One week later, these rabbits were given multiple intravenous injections of formalin-inactivated pneumococci of the cross-reactive type by an established method. Each of the resultant antisera were specific for the cross-reactive type indicating that the previous injection of the polysaccharide had induced epitope-specific tolerance. This method was successful for production of antisera against pneumococcal types 6A, 6B, 9N, 9V, 19F and 19A. Polyclonal rabbit pneumococcal antisera have some advantages over murine monoclonal antibodies for serologic studies and this method should be applicable for producing type-specific antibodies to cross-reactive polysaccharides of clinical interest. Further, this method is simpler and generally produces higher titered monovalent (factor) reagents than absorbed antisera.


Relationship between electroporation conditions, electropermeability and respiratory activity for Frankia strain ACN14a. The use of electroporation for introducing macromolecules into intact cells of the actinomycete Frankia was investigated. Electropermeability was demonstrated by the uptake of dextran (70 kDa) molecules labeled with fluorescein isothiocyanate (FITC) inside Frankia cells. Upon pulsation with an exponentially decaying electric field, the cell membranes became permeable. Loading increased with initial pulsed electric field strength and capacitance. Increased loading efficiency was inversely related to INT (2-(p-iodophenyl-3-(p-nitrophenyl)-5- phenyltetrazolium chloride) reduction activity (respiring bacteria) of the cell population. The presence of CaCl2 in the electroporation and resealing buffer raised INT-reduction activity but K2SO4 decreased this activity. Resealing of electropores was confirmed by a decreasing FITC-dextran loading through the recovery period. The use of FITC-dextran molecules and INT-reduction assay are two new approaches for the study of permeabilization and cellular activity of electroporated bacteria.


Genetic variation in two bone-related proteins: is there an association with bone mineral density or skeletal size in postmenopausal women? In an effort to determine if structural variation in proteins important in bone metabolism might influence bone mineral density (BMD) and thus be a determinant of susceptibility to osteoporosis in older women, the authors typed a group of 258 non-Black women (age 65-90) participating in the Study of Osteoporotic Fractures (SOF) for two polymorphic bone-related proteins, group specific component (Gc), also known as vitamin D-binding protein, and alpha 2HS glycoprotein (AHSG). These two proteins exhibit common structural variation in populations that can be detected by isoelectric focusing/immunoblotting of serum. An important function of Gc is the binding, solubilization, and transport of vitamin D sterols in the bloodstream while AHSG is a glycoprotein constituent of calcified cortical bone matrix. There are six common phenotypes of Gc and four of AHSG. Using Gc or AHSG phenotypes as categorical variables, statistical analyses were done to determine if bone mineral density of the proximal or distal radius or calcaneus differed by phenotype. Neither Gc nor AHSG phenotype demonstrated a statistically significant relationship with BMD at any site. Adjustments for age and degree of obesity did not substantively affect these results. Subsequent analyses to determine if phenotype of either of these proteins was associated with variables related to skeletal size showed an association of AHSG with height (P less than .02). This may indicate that AHSG phenotype is related to postmenopausal loss of height, or it may be a chance statistical finding.


Familial analysis of eosinophilia caused by helminthic parasites. A highly significant familial aggregation of eosinophil levels (X2(3) = 38.00) was detected in a sample from three Brazilian populations with a high incidence of helminthic parasitism. The data were unable to resolve genetic or common environment causation due to the lack of environmental concomitant variables. Results of path analysis indicate that the familial cause accounts for about 58% of the total variability of eosinophil levels among parasite-infected individuals.


Do bilineal pedigrees represent a problem for linkage analysis? Basic principles and simulation results for single-gene diseases with no heterogeneity. Some investigators have expressed concern--especially for psychiatric disorders--that bilineal pedigrees should not be included in linkage studies. This study compares the "informativeness" of bilineal and unilineal families for a homogeneous single-gene disorder. Three approaches were used: (1) simulation studies of three-generation pedigrees, (2) calculation of expected lod scores (ELODs) in nuclear families, and (3) calculation of Fisher's information number I(theta) in nuclear families. The simulation studies in (1) permitted a realistic comparison between bilineal datasets and purely unilineal ones. The calculations in nuclear families in (2) and (3) then made it possible to analyze the sources of information loss in bilineal families. Overall, in datasets of five three-generation pedigrees each, the drop in mean maximum lod score was approximately 50% from purely unilineal datasets to extremely bilineal ones. In less-extreme bilineal datasets, which are closer to most real data than the extremely bilineal ones, the drops in lod score were very small--less than 10% in some, and practically zero in others. The details will vary, depending on size and structure of the pedigree, genetic model, true value of the recombination fraction, and informativeness of the marker. However, these results imply that the information loss due to bilineality is not necessarily very great. The nuclear-family calculations showed that for phase-known matings there is relatively little information loss in bilineal families, but for phase-unknown matings there the loss is much greater. In conclusion, for single-gene disorders with no genetic heterogeneity, whereas bilineal families can be less informative than comparable unilineal families, they are not so much less informative that they should automatically be discarded from linkage datasets. The implications of bilineal pedigrees for linkage studies of heterogeneous disorders are also discussed.


Detection of genetic heterogeneity for complex quantitative phenotypes. Statistically characterizing factors responsible for quantitative phenotype expression (e.g., polygenes, major genes, shared household factors, etc.) through model selection strategies is a difficult task. A great deal of effort has been expended on refining mathematical and computational aspects of various segregation models used to characterize unique expressions of quantitative phenotypes in an effort to make these models easier to implement and evaluate for a given set of data. In this paper a slightly different angle is emphasized: namely, the explicit modeling of the potentially numerous heterogeneous genetic and environmental processes (i.e., segregation patterns, household aggregations, etiologic processes, etc.) that could contribute to the overall variation of a quantitative trait. As such, this paper describes tools for detecting quantitative trait heterogeneity that are meant to answer such questions as "are there pedigrees among a great many that show a pattern consistent with a possibly very specific single locus segregation pattern while the rest show compatibility with a polygenic or purely environmental pattern?" Methods for determining the significance of such heterogeneity are also discussed, as are the results of numerous examples and simulation studies carried out in an effort to validate and further elaborate aspects of the proposed techniques.


SPECT imaging in psychiatry. A review.

SPECT imaging in psychiatry. A review. In the last two decades, brain imaging has become an integral part of clinical and research psychiatry. Single photon computed emission tomography (SPECT) is rapidly gaining acceptance as one of the major imaging techniques available, along with computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET). Each of these techniques has its assets and drawbacks. This review concerns SPECT, a highly prevalent imaging technique whose potential value in brain imaging has not been appreciated until recently. Its purpose is to expose practicing clinicians and research psychiatrists alike to the attributes of this instrument, which is available in most nuclear medicine departments today. An effort is made to provide a comprehensive account of this technique, including a brief summary of the basic principles, the various methods of its application, and recent findings in most psychiatric disorders. Analogies to its "aristocratic cousin," PET, are presented to emphasize similarities and differences. Finally, directions for future development and implementation of SPECT are suggested.


Prevalence of psychiatric disorders in three primary-care clinics in Beersheba, Israel. Concurrent assessment by the General Health Questionnaire, General Practitioners, and Research Diagnostic Criteria. The General Health Questionnaire (GHQ) had identified fully 69% of 776 respondents who attended 12 primary-care clinics as "probable cases" of psychiatric disorders, whereas the general practitioners (GPs) involved had thought only 31% had psychological problems. To investigate more accurately the prevalence of psychiatric disorders we examined 112 of the original sample with the Schedule for Affective Disorders and Schizophrenia, Life-time version and found only 15% to have had a Research Diagnostic Criteria disorder at the time of the initial study. Raising the GHQ threshold to 15/16 improved specificity and positive predictive value, and improved GPs' case-finding modestly. These respondents either suffered from high rates of subclinical distress or readily report subjective distress in the clinic, or both.


Crying following stroke. A report on 30 cases. Following stroke, many patients experience a heightened tendency to cry. The aim of the present study was to provide a detailed description of this behavior and its accompaniments. Thirty stroke patients who had cried in the previous month were studied using a detailed structured clinical interview. There was a wide range of frequency of crying. The components of crying combine in a more complex and varied way than commonly held stereotyped views suggest. No distinct subtypes were identified. Further research is required to determine the relationship between emotionalism and the frequency and severity of symptoms of depression.


The comorbidity of DSM-III-R personality disorders in somatization disorder. In order to understand psychiatric factors that complicate the medical management of somatizing patients, 94 subjects with known somatization disorder (SD) were evaluated for 13 personality disorders with the Structured Clinical Interview for DSM-III-R Personality Disorders. Referred from multiple primary care settings, the patient sample was predominantly female (85%), married (67%), high school graduates (64%), and had a mean age of 43. Structured interviews documented that 23.4% of SD patients had one personality disorder, and 37.2% had two or more disorders. The four most frequently identified personality disorders were avoidance 26.7%, paranoia 21.3%, self-defeating 19.1%, and obsessive-compulsive 17.1%. Interestingly histrionic personality disorder was identified in only 12.8% of the sample and antisocial personality disorder in 7.4%. In making the diagnosis of SD, health care providers need to avoid the common clinical impression that histrionic behavior often accompanies the disorder. Further research with SD patients is needed to examine the relationship of co-occurring personality disorders to symptom recurrence, health care utilization, and readiness for psychiatric referral.


Resuscitation. Patient and staff attitudes in the context of cancer. One hundred oncology and hematology cancer patients from a major teaching hospital and their treating doctors were studied regarding their attitudes toward cardiopulmonary resuscitation (CPR). A descriptive approach was used, incorporating semistructured interviews of patients and medical staff and established questionnaire measures, examining knowledge of and attitudes toward disease and treatment, and projected attitude toward CPR and current psychological functioning. One-third of the patient sample anticipated a time when they would not consent to cardiopulmonary resuscitation. This was significantly associated with good disease prognosis. Patients with a psychiatric past history were also overrespresented. It appears that patient attitude to treatment withdrawal and refusal of CPR is related to disease progression and likely to change over time. This supports a dynamic and evolving model of advance directives rather than any fixed decree. Medical staff reported that they planned to provide half the sample with intensive medical treatment (including Intensive Care support in the event of their cardiac arrest), and 32% were designated for ward-based resuscitation only. Eighteen percent would not be resuscitated. These patients were older, had more treatment side effects, and a poorer quality of life. Those patients with either a psychiatric past history or higher ratings of depressive affect were also overincluded in the doctors' "Do-Not-Resuscitate" (DNR) group. These results suggest that there are other qualitative factors (e.g., current psychological functioning and past psychiatric history) that contribute to DNR decisions beyond the usual disease-based criteria seen in formal DNR protocols.


Thyroid screening tests in psychiatric inpatients. This study reports on a retrospective evaluation of the current practice of screening for thyroid dysfunction in an adult psychiatric inpatient program. Sixty-four percent of 342 admissions were tested during their hospital stay. Although 13.7% of tests yielded abnormal values on one or more of the thyroid indices, only 0.9% resulted in a diagnosis of hypothyroidism. None of the other abnormal test results led to any specific action being taken. The present pattern of use of thyroid function screening as observed in this study does not appear optimal. Issues in the selection of thyroid screening tests, and the value of the results obtained are discussed.


Dissociative experiences among psychiatric inpatients. The Dissociative Experiences Scale was administered to 299 inpatients on an acute care general adult psychiatric ward over a 2-year period. The average score was 14.6, which is significantly higher than the mean for the general population. About one in six inpatients reported very high scores above 50 on the seven most common items in the scale, indicating a high level of dissociative psychopathology. Based on the responses to four items which form a scale factor called Activities of Dissociated States, an estimate is made that 6%-8% of general adult inpatients may have multiple personality disorder. Dissociative psychopathology is common on inpatient units.


Use of increased anesthetic dose prior to electroconvulsive therapy to prevent postictal excitement. The authors report on three patients who developed severe postictal excitement at several consecutive electroconvulsive therapy (ECT) treatments. In all three cases, an increase in the anesthetic (or equivalent medication) dosage prior to ECT prevented the emergence of postictal excitement at subsequent treatments. This strategy, among others, should be considered in the management of patients who repeatedly manifest this phenomenon during a course of ECT.


[Analysis of the origin of the Vietnam dairy cow breed using the results of marker character study]. The phylogenesis analysis of Vietnam milk cows breed was performed using eleven different mathematical methods. 14 to 144 markers were used in this analysis, whose synthesis is controlled by eleven genetical systems of blood groups and six polymorphic systems of proteins. It has been demonstrated that the accuracy of the phylogenesis analysis depends on the quality of the markers applied and on the methods used. It was established that the way of breed formation was reflected in the dendrogram composed by the matrix based on the formula of Eisner and Meshcheryakova (1978). The properties of other methods in use are discussed.


[Genetic analysis of some behavioral and physiologic characters in hybrids between hypertensive and normotensive rats. Analysis of the nature of the inheritance]. As a result of crosses between the SHR rats (spontaneously hypertensive strain) and WKY rats (normotensive strain), the F1 and F2 hybrids and the B1 and B2 backcrosses were obtained. Analysis of genetic control nature in these generations revealed that the WKY genes responsible for the level of arterial pressure, sensitivity to the electric current stimulation and salt (sodium and potassium) appetite characteristics were dominant. The heterosis effect was found for the body mass. Analysis of dynamics of different types of exploratory activity (in a shuttle box, in "horizontal plane", in an open field) demonstrated specificity of their genetic formulae and peculiarities of changes in their genetic control during the test.


[Transcription activity of ribosomal genes in the pre- and postnatal periods of human development]. Transcriptional activity of silver-stained nucleolar-organizing region (NOR) of human chromosomes was studied in 50 medical abortuses at 6-12 weeks of gestation and 125 healthy individuals from 20 to 85-years-old. Transcriptional activity of rRNA genes was higher at the prenatal period of ontogenesis than at the postnatal period. Decline in total activity of ribosomal genes in both sexes was shown. Linear regression coefficients of the NOR activity in dependence of age satisfactorily predict the level of total NOR activity at the prenatal period of human development.


[Ecologic ultraviolet--a real mutagenic factor for vegetative cells of Bacillus subtilis]. The frequency of leu----Leu+ reversions represented mainly by suppressor mutations is increased in Bacillus subtilis uvr+ and uvr-1 cells after exposure to natural sunlight. Dependence of mutation yield on the time of exposure is linear (one hit kinetics) in case of the uvr-1 strain. In the uvr+ cells the yield of mutations is also linear, but only at short times of exposure, the curve bending and levelling off the plateau after 10-min cell illumination. It has been established in the experiments with optical filters that the mutagenic effect is related to wavelengths which correspond to the UVB zone of ecological UV. The mutagenesis caused by sunlight can be modified (weakened) by some post-irradiation treatments of bacteria, which also led to a decrease of mutations frequencies in B. subtilis uvr+ and uvr-1 cells after exposure to 254-nm UV. The data indicate that: 1) mutagenic influence of sunlight can be overcome only by the joint action of activities of the two cellular repair systems--photoreactivation and excision repair, 2) the real mutagenic effect of sunlight on such a non-photoreactivating organism as B. subtilis would not be enhanced with the increase of the UVB flow in sunlight spectrum.


[Integration of the plasmid-cloned lysA gene of Bacillus subtilis into the chromosome of this microorganism]. Integration of the Bacillus subtilis lysA gene cloned on pLP1 plasmid, into the 250 degrees region of the chromosome of this microorganism was performed. Significant differences in the level and character of their expression were shown between lysA gene integrated into the chromosome and plasmid-borne genes. It is suggested that the expression of the lysA gene could be under control of a certain cis-acting factor which is able to promote transcription of the lysA gene and mediate gene specific regulation.


[The plasmid pEJ6.6 carrying the activated c-Ha-ras-1 oncogene increases the mutation frequency in Chinese hamster cells]. The induction of gene mutations and chromosome aberrations by the plasmid pEJ6.6 carrying the activated c-Ha-ras-1 oncogene from human bladder carcinoma was studied in cultured Chinese hamster cells. Both an increase in the frequency of gene mutations to 6-mercaptopurine resistance and of chromosome aberrations was observed after pEJ6.6 treatment as compared to control series (pBR322). Thus the results of experiments carried out show that the pEJ6.6 plasmid possesses a mutagenic activity.


The foraging locus: behavioral tests for normal muscle movement in rover and sitter Drosophila melanogaster larvae. We used Drosophila melanogaster larvae with different alleles at the foraging (for) locus in a variety of behavioral tests to evaluate normal muscle usage of rover and sitter phenotypes. The results show that sitter and lethal sitter alleles of for do not affect larval behavior through a mutation which affects larval muscle usage. In general the behavior of rovers and sitters differed on food but not on non-nutritive substrates. Rovers and sitters moved equally well on non-nutritive substrates, and measures such as the time to roll over and length of forward stride showed no significant strain differences. Larvae with different alleles at for did not differ in body length. Rovers took more strides, not longer ones, than sitters while on foraging substrates. We conclude that differences in larval locomotion during foraging found in larvae with different alleles at for can not be explained on the basis of muscle usage alone. It is more likely that for affects larval ability to perceive or respond to the foraging environment.


Karyotypic comparison among Cebuella pygmaea, Callithrix jacchus and C. emiliae (Callitrichidae, Primates) and its taxonomic implications. The karyotype of Cebuella pygmaea (2n = 44) obtained by G-, C-banding, and NOR-staining is described. This species presents a heteromorphic C band in the intersticial region of the short arm of chromosome 2. The data obtained were compared with those previously described for the karyotypes of Callithrix jacchus and Callithrix emiliae. The three species differ in the amount and distribution of non-centromeric constitutive heterochromatin. The importance of the variation in constitutive heterochromatin for the phylogeny of the group is discussed. Comparison of the karyotypes in terms of G-banding patterns showed that C. pygmaea and C. emiliae differ from C. jacchus by a Robertsonian translocation and a paracentric inversion, whereas C. pygmaea and C. emiliae differ from each other by a reciprocal translocation between an acrocentric autosome and the short arm of the submetacentric chromosomes that distinguishes their karyotypes from that of C. jacchus. The possible evolutionary paths followed by the karyotypes of the three species are discussed.


Topical indomethacin in the treatment of chronic cystoid macular edema. Eighty percent of 30 eyes with chronic cystoid macular edema (CME) after cataract extraction achieved improved visual acuity of three or more lines when treated with 1% indomethacin eye drops. Of these patients 53% demonstrated an "on/off" phenomenon induced by the initiation and cessation of treatment documented by visual acuity measurements and fluorescein angiography. This "on/off" phenomenon suggests that there is a direct relationship between the use of 1% indomethacin eye drops and the resolution of chronic CME after cataract extraction. Previous studies on the treatment of CME with indomethacin have not addressed the use of indomethacin eye drops for chronic CME.


Intraocular pressure determination in infants with severe retinopathy of prematurity. We determined intraocular pressure (IOP) in 55 premature infants (122 determinations) with stage V retinopathy of prematurity (ROP) by applanation and indentation tonometry corrected for scleral rigidity and found a modest correlation of r = 0.52 between readings. Chronologic age and the scleral rigidity coefficient were the most significant factors affecting the closeness in readings. Our findings suggest that the applanation method of obtaining IOP values is preferable in infants with ROP because this method is less affected by technical error and the variable nature of premature infant sclera. Frequent examination may be necessary to detect an early IOP increase, especially in infants who have had successful retinal reattachment through vitreoretinal techniques.


Chlamydia keratoconjunctivitis determination of Chlamydia trachomatis specific secretory immunoglobulin A in tears by enzyme immunoassay. Determination of Chlamydia trachomatis specific antibodies in serum and tears, isolation of C. trachomatis in cell culture and C. trachomatis antigen detection by direct immunofluorescence test were evaluated for the laboratory diagnosis of Chlamydia trachomatis infection in 30 patients with chronic conjunctivitis. C. trachomatis specific secretory immunoglobulin A (s-IgA) was detected in the tears of all 8 patients with a positive result in culture and the direct immunofluorescence test. In 4 additional patients, the s-IgA assay of tears was also positive. A presumptive clinical diagnosis of Chlamydia conjunctivitis was correlated with the presence of s-IgA in tears. S-IgA was not detected in the serum of any of the patients, indicating that s-IgA is locally produced and not transudated from the serum. For the diagnosis of chronic Chlamydia conjunctivitis, we recommend the determination of s-IgA in tears in addition to a test for Chlamydia detection.


Apparent cleavage of the retinal nerve fiber layer in asymptomatic eyes with high myopia. The appearance of the retinal nerve fiber layer was studied in one eye of 203 normal Asians (59 with high myopia greater than or equal to -5 D, and 144 with emmetropia or hyperopia). "Cleavage" of the retinal nerve fiber layer was observed in 3 of these 59 highly myopic eyes, but there was no significant damage to either the retinal pigment epithelium or the choroid. In contrast, no cleavage was observed in the other 144 emmetropic or hyperopic eyes. High myopia (P = 0.0237, Fisher's exact test) was a significant risk factor for "cleavage" development in the retinal nerve fiber layer. The occurrence of a defect (nerve fiber loss) in the retinal nerve fiber layer in severe myopia (5/59, 8%) was also greater than that in either emmetropia or hyperopia (2/144, 1%; P = 0.0229). These results indicate that subtle changes can occur in the appearance of the retinal nerve fiber layer of the eye in some patients with asymptomatic myopia.


Extracellular matrix changes of the optic nerve lamina cribrosa in monkey eyes with experimentally chronic glaucoma. Using light microscopic immunohistochemistry, we studied the immunolocalization and immunoreactivity of the extracellular matrix, including collagen types III, IV, VI, laminin, and alpha elastin in the lamina cribrosa of monkey eyes with normal and experimentally chronic glaucoma. Our results showed: (1) abnormal linearlike immunodeposits of both collagen type IV and laminin in the margin of the lamina cribrosa with significant density in the glaucomatous eyes; (2) the immunoreactivity of collagen type III resembled that of the normal eye, but was slightly stronger at the laminar surface; (3) findings with collagen type VI resembled those of type III with an enhanced linearlike staining surrounding the nerve-fiber bundles. Furthermore, staining of alpha elastin demonstrated dramatic changes in both reactivity and localization. The lamina cribrosa of glaucomatous eyes showed a markedly reduced immunoreactivity as well as an irregular, interrupted pattern. These observations suggest that the changes might be a secondary to the long-standing elevation of intraocular pressure. The alteration of these macromolecules may modify the course of glaucomatous optic damage.


Immunohistochemical detection of extravasated fibrinogen (fibrin) in human diabetic retina. In diabetic retinopathy, breakdown of the blood-retinal barrier is an early functional disorder that can cause retinal edema, which in turn results in visual disturbance. Hard exudates, composed mainly of lipid and proteinaceous material, are one sign of chronic retinal edema caused by long-standing leakage from the vessels due to breakdown of the blood-retinal barrier. Utilizing diabetic retinas in which hard exudates were present, we performed immunohistochemical staining for fibrinogen. Because fibrinogen is a serum protein, its extravascular localization implies the existence of blood-retinal barrier breakdown. Our studies showed that the extravasated fibrinogen from blood-retinal barrier breakdown accumulated in the hard exudates and in areas of hemorrhage found primarily in the outer plexiform layer and was then phagocytosed by macrophages.


Digital image analysis of optic nerve head pallor as a diagnostic test for early glaucoma. We developed a computer-based technique to quantify optic nerve head pallor from videographically acquired digitized optic nerve images and tested the ability of pallor measurements to discriminate between normal eyes and eyes with early glaucoma. Corresponding pixel values from images obtained under 540 nm (green) and 640 nm (red) light with a videographic fundus camera were used to quantify optic nerve head pallor. A pallor density histogram was calculated for each eye, and contained values between 0 (red) to 1 (white). A measure of the distribution width of the histogram provided pallor measurements standardized to the measurements of the large veins of the disc. A database of one eye each of 44 normal controls and 70 patients with early open angle glaucoma was used to test the measurements for diagnostic sensitivity and specificity. These standardized pallor measurements did not perform better than absolute pallor measurements to discriminate between normal and glaucomatous eyes. The sensitivity and specificity of standardized pallor measurements (49% and 57%, respectively, for this database) were not as good as those for stereoscopic measurements of disc rim area in the same database (70% and 73%). Pallor measurements of this type do not appear to be sensitive or specific indicators of early glaucoma.


Alterations of saccadic eye movements in myotonic dystrophy. Saccadic eye movements were examined by means of infrared reflection oculography in 8 patients having myotonic dystrophy and in 65 control subjects. In 7 patients typical alterations of the saccades could be observed. In comparison with the normal controls the saccades were significantly hypometric, of longer duration, of lower peak velocity, and showed a typical pattern of velocity and acceleration.


Retinal vessel autoregulation in sickle cell patients. We tested retinal vessel autoregulation in 16 sickle cell patients and 6 controls by computer-assisted measurements of constriction of the superior and inferior temporal veins and arteries after pure oxygen breathing. Compared to the controls and corrected for age, we found a decrease of vasoconstriction in three of the four vessels measured in the sickle cell group, which was statistically significant only for the superior temporal artery (P 0.009). The number of patients was too small to allow a separate analysis of possible contributory factors within the sickle cell group, such as sickle cell hemoglobin subtype and extent of retinal ischemia. Our findings indicate a factor not yet well known in the pathophysiology of sickle cell disease: an abnormality of local microvascular control.


A comparative study of optic nerve head in low- and high-tension glaucomas. The disc and rim areas in 15 eyes from 15 selected low-tension glaucoma (LTG) patients were compared with those in 15 eyes from 15 selected high-tension glaucoma (HTG) patients. In all patients, visual field defects (VFD) were at an early stage (mean deviation greater than -5 dB, program 30-2 of Humphrey Visual Field Analyzer, STATPAC) and were confined to either the upper or lower hemifield. There were no significant differences in the degree of VFD between LTG and HTG, and the peak intraocular pressure averaged 18.9 and 29.2 mmHg for LTG and HTG eyes, respectively. The disc and rim areas were determined from stereoscopic disc photographs using the method of Littman. The half rim area corresponding to the upper or lower hemifield without VFD was significantly smaller for LTG than HTG (LTG 0.26 +/- 0.08 mm2, HTG 0.31 +/- 0.08 mm2, mean +/- SD, n = 15, P less than 0.005). The rim area corresponding to the upper or lower hemifield with VFD was also significantly smaller for LTG than HTG (LTG 0.19 +/- 0.08 mm2, HTG 0.24 +/- 0.08 mm2, P less than 0.01). On the other hand, there was no significant difference in the disc area between LTG and HTG (LTG 1.96 +/- 0.57 mm2, HTG 2.03 +/- 0.45 mm2, P greater than 0.4). It was suggested that the differences in rim area were already present prior to the manifestation of the VFD.


Effect of dexamethasone 0.1% and prednisolone acetate 1.0% eye drops on the blood-aqueous barrier after cataract surgery: a controlled randomized fluorophotometric study. Using non-invasive anterior chamber fluorophotometry, we performed a double-blind, randomized clinical trial on the effects of dexamethasone 0.1% and prednisolone acetate 1.0% eye drops on the blood-aqueous barrier after phacoemulsification and posterior chamber lens implantation. Twenty patients received one of the preparations topically to the surgically treated eye 5 times daily for a period of 5 days, beginning the day after surgery. Patients chosen for the study had no history of eye disease other than senile cataract nor of systemic diseases influencing the eyes. No other steroids or non-steroidal anti-inflammatory drugs were given before or during the investigation. The fluorometric data measured 5 days after surgery show a lower mean concentration of fluorescein in the dexamethasone alcohol 0.1% treated group compared with the prednisolone acetate 1.0% treated group. The difference is statistically not significant. The clinical assessment of postoperative ocular inflammation did correlate with the fluorophotometric measurements. The results of the study indicate that although dexamethasone is the more potent anti-inflammatory agent, with a better binding affinity to glucocorticoid receptors, we are--with the number of cases measured--unable to demonstrate any difference in the efficacy in protecting the blood-aqueous barrier after cataract extraction and posterior chamber lens implantation to prednisolone acetate.


Bullous retinal detachment and multiple retinal pigment epithelial detachments in patients receiving hemodialysis. Two patients receiving hemodialysis for chronic renal failure developed bilateral bullous retinal detachment associated with multiple underlying serous detachments of the pigment epithelium. Many of the detachments of the pigment epithelium were surrounded by subretinal whitish exudate that was probably fibrinous in type. There was fluorescein angiographic evidence of dehiscence of the pigment epithelium at the margin of some of the pigment epithelial detachments. Failure to recognize the nature of the retinal detachment in one patient resulted in an unsuccessful scleral buckling procedure.


Prognostic value of new retinal tears associated with the development of postoperative proliferative vitreoretinopathy. We prospectively evaluated for the presence of new retinal tears 60 eyes of 60 patients who developed recurrent retinal detachment complicated by proliferative vitreoretinopathy (PVR) after surgery for primary rhegmatogenous retinal detachment. New retinal tears associated with the development or recurrence of postoperative PVR were disclosed in 27 eyes (45%). New tears were categorized into two distinct groups: (1) peripheral new tears and (2) posterior new tears. Peripheral new tears were disclosed in 11 eyes. They were invariably located at the posterior edge of the vitreous base and showed a prevalence in the inferior quadrants. The prognosis for permanent retinal reattachment after reoperation was not influenced by the presence of peripheral new tears. Posterior new tears were disclosed in 19 eyes. They were located in the mid-periphery or close to the posterior pole. They were more frequent in grade D PVR (57.7%) compared with grade C PVR (11.7%) (P less than 0.01). Posterior new tears were associated with a poor prognosis. In grade D PVR the anatomic success rate following repeated surgery was only 13.3% (2/15 eyes), whereas all eyes with grade D PVR and no posterior new tears were successfully reattached (P less than 0.001). Failures to reattach the retina were related to recurrent PVR. It is concluded that the development of posterior new tears in postoperative PVR reflects a severe and active PVR process.


Cellular response to intravitreal injection of endotoxin and xanthine oxidase in rabbits. In the present study, the ocular inflammatory response to intravitreally injected endotoxin and xanthine oxidase was studied and the cellular response of the anterior and posterior segments was contrasted. There was a clear dose response relationship to both compounds in aqueous humor protein concentration and aqueous and vitreous humor white cell number. Xanthine oxidase and low doses of endotoxin (0.25 and 1.0 ng) produce a mainly mononuclear response in the anterior segment. Higher doses of endotoxin (10 and 100 ng) produced a predominantly neutrophilic response. Cellular infiltration into the posterior segment differed qualitatively and quantitatively from the anterior segment in response to the same stimuli. Myeloperoxidase (MPO) activity (a marker for neutrophils) of the iris-ciliary body was increased only in those eyes with a large neutrophilic response and thus is not recommended for use as a definitive index of the ocular inflammatory response, but may be a useful adjunct for such studies.


The ultrastructure of transplanted rabbit retinal epithelium. Retinal epithelial cells from pigmented rabbits have been cultured and radiolabelled during division with 3H-thymidine and transplanted to the subretinal space of albino rabbits using a pars plana transvitreal approach. The host rabbits were maintained on cyclosporine immunosuppression after transplantation surgery. The transplant cells survive and maintain a morphologically normal appearance for at least 5 months. The pigmented epithelial cells retain their pigmentation and become integrated with the host retinal epithelium forming junctional complexes with both the host and other transplant cells. The transplant cells contact host photoreceptors with their apical processes and phagocytize outer segments. There appears to be no significant cell division among the transplant cells.


Developmental study of chondroitin-6-sulphate in normal and dystrophic rat retina. The RCS rat is a widely studied model of human retinal dystrophies including retinitis pigmentosa. Chondroitin-6-sulphate (C6S) in the interphotoreceptor matrix was localised immunocytochemically in both the normal congenic and dystrophic strains of the RCS rat up to 65 days postnatally. From postnatal days 5 to 15 the distribution of C6S in both strains was similar, being localised in the interstices of developing inner and outer segments and adjacent to the RPE surface. In the normal rats, the distribution of C6S did not change with age. In the RCS rats, however, at postnatal days 20 to 35 staining was observed as a dense band at the junction of inner and outer segments and no staining was observed adjacent to the surface of the RPE. At postnatal day 45 onwards there was a decrease and a complete absence of C6S staining in these rats. This change in the pattern of staining correlated with the morphological observation of the progressive degeneration of photoreceptor cells suggesting that C6S may be important in photoreceptor degeneration in the RCS rat.


Toxicity of 1-(beta-D-arabinofuranosyl)cytosine after intravitreal injection in the rabbit eye. The retinal toxicity of intravitreally injected 1-(beta-D-arabinofuranosyl)cytosine (cytarabine) was examined in 7 chinchilla rabbits to determine if cytarabine can be used as local therapy for vitreoretinal non-Hodgkin's lymphoma. Fractionated dose of 600 micrograms, 1500 micrograms, and 2700 micrograms cytarabine in stabilized saline were given intravitreally in one eye (2 x 300 micrograms, 5 x 300 micrograms, and 3 x 900 micrograms, respectively, with an interval time of 24 h) and stabilized saline in the other eye as control. Toxic effects were evaluated with biomicroscopy, direct ophthalmoscopy, fluorophotometry, electroretinography, light, and electron microscopy. Toxic effects were found with the 1500 micrograms and 2700 micrograms doses only. They consisted of a temporary impairment of the blood retina barrier function for fluorescein as measured by fluorophotometry and an irreversible change of the b-wave in the electroretinograms. No histopathologic changes were seen under the light microscope. Electron microscopic examination showed aberrations in the synaptic pedicles of the photoreceptor cells at a dose of 1500 micrograms cytarabine. The results suggest that the cytarabine dose that is expected to be therapeutic for vitreoretinal non-Hodgkin's lymphoma (about 90 micrograms given in three doses of 30 micrograms) is non-toxic for ocular structures.


Vitreous, retinal and subretinal hemorrhages associated with von Willebrand's syndrome. Two patients with von Willebrand's syndrome had intraocular hemorrhages without trauma or neovascularization. A 13-year-old Japanese girl complained of sudden spotted vision in her left eye. Vitreous, peripapillary retinal, and subretinal hemorrhages were seen by ophthalmoscopy in the affected eye. In addition, a 19-year-old Japanese man had repeated vitreous hemorrhage and epistaxis. Also noted was gyrate atrophy of the choroid and retina. Analysis of the coagulation-fibrinolysis system revealed decreased activities of Factor VIII and von Willebrand's factor in both patients. The amount of von Willebrand's factor antigen also was decreased. These results suggested that the patients had von Willebrand's syndrome. The bleeding tendency in the disorder appeared to be responsible for the pathogenesis of the intraocular hemorrhages seen in these patients.


Low-dose danazol for vascular access and dialyzer thrombosis in hemodialysis patients. Four hemodialysis patients (1 male and 3 females, aged 29-40 years) with unusual recurrent vascular access or dialyzer thrombosis were studied to find out whether a hypercoagulable state exists. Measurements of euglobulin clot lysis time (ELT), fibrinogen, antithrombin III (AT III), protein C (PC), protein S (PS), tissue plasminogen activator (tPA), and plasminogen activator inhibitor (PAI) were done. Results indicated that all patients had prolonged ELT, low tPA, elevated PAI, normal AT III, and PS. Three patients had elevated fibrinogen level and two had low PC. Danazol 200 mg orally once a day effectively prevented any further thrombosis. In 4 weeks' time, all the abnormal coagulation studies normalized in addition to elevation of AT III, PC and PS. Only 1 female patient had a prolonged menstrual period, which was reversed by lowering the daily dose of danazol to 100 mg. No other side effects were encountered. These data indicate that hypofibrinolysis may play a major role in vascular access or dialyzer thrombosis and that low-dose danazol may provide an effective prophylaxis and treatment. Larger controlled studies are needed to confirm these findings.


Factor VIII concentrates in HIV-1-positive hemophiliacs--is pure better? 39 human immunodeficiency-virus-1 (HIV-1)-positive hemophiliacs who had been regularly treated with non-virus-inactivated intermediate-purity factor VIII concentrates were divided into two groups. Group A consisted of 21 patients with a CD4/CD8 cell ratio of less than 1.0 and group B of 18 patients with a CD4/CD8 cell ratio of greater than 1.0. All patients of group A were switched to a high-purity virus-inactivated factor VIII concentrate, whereas patients of group B continued to receive the intermediate-purity concentrate. There was no significant difference in the average decline of CD4 cells between the two groups during the observation period. 9 patients of group A and 4 patients of group B developed AIDS. 5 patients of group A but 11 patients of group B remained clinically asymptomatic. We conclude that the 15-fold increase in purity of the factor VIII concentrate had no apparent beneficial effect on the CD4 cell counts in this patient group.


Electrophoretic studies on molecular defects of von Willebrand factor and platelet glycoprotein IIb-IIIa with antibodies produced in egg yolk from laying hens. Immunoglobulins isolated from egg yolk (IgYs) are a convenient source of polyclonal antibodies. Their purification is simple and the yields important (50 mg immunoglobulins/egg). Nevertheless their biochemical characteristics are different from those of rabbit antibodies generally used for the study of molecular defects of plasmatic and platelet proteins. Provided standardization is achieved, IgYs can be used for immunoelectrophoresis, immunoprecipitation or immunoblotting assays. We describe here the electrophoretic and immunoblotting conditions employed to explore human plasmatic and platelet von Willebrand factor (vWF) and human platelet GP IIb-IIIa using IgYs. These two proteins are involved in primary hemostasis and their absence or abnormality is responsible for hereditary bleeding disorders. The methods were applied to the characterization of patients with vWF or GP IIb-IIIa defects and compared to classical mammalian IgG immunoelectrophoretic techniques. Results were further confirmed by flow cytometric analysis.


Isolation of a fibrinolytic protease, M4, from venom of Crotalus molossus molossus (northern blacktail rattlesnake). M4, a fibrinolytic protease, was isolated from the venom of Crotalus molossus molossus. It has a pI of 9.6 and a molecular weight of 27,000. The protease hydrolyzes the A alpha and B beta chains of fibrinogen, and the alpha and beta chains of fibrin. This activity was inhibited by EDTA and restored by Ca2+ or Zn2+, but not Mg2+. The protease hydrolyzed hide power azure and casein, but it had no effect on collagen, hyaluronic acid, complement or synthetic substrates for thrombin, plasmin or kallikrein. Subcutaneous injections into mice with doses as high as 100 micrograms did not cause hemorrhage. This protease may have therapeutic use as a thrombolytic agent.


Fibrinogen Milano IV, another case of congenital dysfibrinogenemia with an abnormal fibrinopeptide A release (A alpha 16 Arg----His). An abnormal fibrinogen, denoted as 'fibrinogen Milano IV', has been found in a 36-year-old woman without any bleeding manifestations or thrombotic tendency. Routine coagulation studies revealed prolonged thrombin and reptilase clotting times, very low plasma fibrinogen concentration determined by the functional assay but a normal fibrinogen concentration measured by the immunologic assay. Turbidity curves, measured following addition of thrombin to purified fibrinogen Milano IV, both in presence of calcium or EDTA, were markedly delayed. Release of fibrinopeptide B by thrombin was normal, whereas only half the normal amount of fibrinopeptide A was cleaved. The fibrinopeptide A peak of fibrinogen was preceded by an abnormal fibrinopeptide A*. Both peaks were collected for amino acid analysis which showed an exchange of arginine by histidine in position 16 of the A alpha chain of the fibrinopeptide A*.


Safety evaluation of dibenzyl ether.

Safety evaluation of dibenzyl ether. Dibenzyl ether (FEMA No. 2371, CAS No. 103-50-4) was given in the diet to rats at a rate of 62, 196 or 620 mg/kg/day for 91 consecutive days. Body weights and food consumption were measured weekly; haematological, clinical chemistry and urinalysis values were obtained at wk 6 and 12. Gross and microscopic pathological changes were observed and organ weights recorded. The high-dose females had increased absolute and relative liver weights; this was considered to be related to dose. Other statistically significant events that occurred sporadically within the test groups were unrelated to dose and were considered to be normal adaptive change. No toxicological or pathological effects were noted at any of the dose levels after 91 consecutive days of feeding dibenzyl ether. A no-effect level was achieved at 196 mg/kg/day. In a 60-kg human, this would be equivalent to approximately 11.8 g/day, assuming a direct relationship between dose and body weight across species. Based on the possible average daily intake of 19.2 mg/day, this would confer a safety factor of 600. The safety factor based on the more realistic consumption per capita of 23.6 micrograms/day would be approximately 500,000.


A 28-day feeding study with ethyl acetoacetate in rats. Ethyl acetoacetate encapsulated in gum arabic was administered in rodent diet for a minimum of 28 consecutive days to groups of 16 male and 16 female rats (Sprague-Dawley strain) at levels of approximately 100, 300 and 1000 mg/kg body weight/day. A further group of 16 male and 16 female rats was given rodent diet containing gum arabic as a control. The administration of ethyl acetoacetate in the diet did not adversely affect the growth or general health of the animals or their food intakes. None of the minor variations observed in the haematology, serum chemical analyses or urine analyses are considered to be indicative of a treatment-related toxic effect. Caecal enlargement was seen in male rats treated with the top dose of ethyl acetoacetate, but this was accompanied by a normal histopathology. Few histopathological abnormalities were observed. Proteinaceous casts were found in the bladder of approximately half the male rats given 1000 mg ethyl acetoacetate/kg, and nephrocalcinosis was a common occurrence in female rats in this dose group. Renal function was unimpaired in treated male and female rats, and the histopathological findings are common in the strain of rats chosen for this study. Although the caecal enlargement and the changes in kidney and bladder of rats given 1000 mg ethyl acetoacetate/kg are noted, it is considered that ethyl acetoacetate did not produce treatment-related adverse effects in rats during this study.


Metabolism of an imidazole fungicide (prochloraz) in the rat after oral administration. The metabolic fate and pathway of the imidazole fungicide prochloraz (1-[N-propyl-N-2-(2,4,6-trichlorophenoxy) ethyl carbamoyl] imidazole) were investigated in the rat after administration of oral single doses with radiolabelled molecules. At both dose levels (50 and 250 mg/kg body weight), virtually all of the ingested [14C-phenyl]prochloraz was excreted in the urine or faeces within 96 hr, the bulk of excretion occurring between 24 and 48 hr after dosing. Urinary elimination accounted for 61 and 68% of the respective initial doses. Urinary metabolic products were isolated and identified by thin-layer chromatography, gas chromatography or gas chromatography coupled with mass spectrometry analysis. Prochloraz was completely metabolized with no unchanged compound being excreted in the urine. The main biotransformation products in rat urine were 2,4,6-trichlorophenoxyacetic acid and its corresponding alcohol, the latter as a glucuronic acid conjugate. Ring hydroxylation also occurred, with the hydroxy-2,4,6-trichlorophenoxyethanol and hydroxy-2,4,6-trichlorophenoxyacetic acid metabolites excreted in small amounts in the urine. 2,4,6-Trichlorophenol and unconjugated 2,4,6-trichlorophenoxyethanol were identified as minor urinary metabolites.


A comparative study of micronucleus frequency in peripheral blood lymphocytes of human subjects given dietary cis, trans and saturated fat. The micronucleus test using peripheral blood lymphocytes has been used to study the clastogenic effects of saturated, cis or trans fatty acids in human volunteers. Consumption of diets rich in either saturated fats (palmitic acid), monounsaturated cis fats (oleic acid) or monounsaturated trans fats (elaidic acid) for 3 wk had no effect on either the number of micronuclei or the frequency of micronucleated cells in lymphocytes in culture. This study adds to the accumulating body of evidence to suggest that dietary intake of trans fatty acids is not especially linked to genetic damage.


Effects of indole-3-carbinol on biotransformation enzymes in the rat: in vivo changes in liver and small intestinal mucosa in comparison with primary hepatocyte cultures. Groups of male Wistar rats were fed semi-synthetic diets containing 0, 200 or 500 mg indole-3-carbinol (13C)/kg for 2, 7, 14 or 28 days. After 2 days, P-450 activities were already induced, but the isoenzyme pattern induced was different in the liver and the small intestine. Hepatic P4501A1, P4501A2 and P4502B1 apoprotein levels were dose-relatedly enhanced, whereas in the small intestine induced levels of P4502B1 and P4501A1 were detected but P4501A2 was not induced. Pentoxy- and ethoxyresorufin dealkylation (PROD and EROD) were dose-relatedly enhanced in the liver (5- and 7-fold, respectively, in the higher dose group) as well as in the small intestine (8- and 13-fold, respectively, at 500 mg 13C/kg diet). Testosterone 16 alpha- and 16 beta-hydroxylation in the small intestine were enhanced (6-9-fold) from day 2 onwards, but in the liver these activities were only slightly enhanced from day 7 onwards. Thus, the major forms induced in the liver appear to be P4501A1, P4501A2, P4502B1 and, to a lesser extent, P4503A, whereas in the small intestine all of the effects that were found are associated with only one cytochrome P-450, P4502B1. After 2 days I3C (500 mg/kg) induced glutathione S-transferase in the liver (1.3-fold) and small intestine (1.5-fold). Hepatic glucuronyl transferase (GT1) was induced (about 1.6-fold) after 7, 14 and 28 days. DT-diaphorase was induced in the liver (2.7-fold) and small intestine (1.5-fold) after 14 days of exposure to 500 mg I3C/kg diet. Treatment of rat hepatocytes with indole-3-acetonitrile and 3,3'-diindolylmethane, but not I3C and indole-3-carboxaldehyde, enhanced EROD activity and halved testosterone 16 alpha- and 2 alpha-hydroxylation. All four indoles slightly induced glutathione S-transferase in cultured hepatocytes. Thus, the in vitro studies suggest that the in vivo effects of I3C have to be attributed to indole-condensation products, such as 3,3'-diindolylmethane, but not to I3C itself.


Comparison of cereal-based diet with purified diet by short-term feeding studies in rats, mice and hamsters, with emphasis on toxicity characteristics. Animal diets used in toxicity studies are prepared either from natural ingredients (cereal-based diet) or from more refined products (purified diet). The type of diet may influence both the outcome of the study and the values obtained with the various parameters in test and control animals. To detect the parameters sensitive to changes in diet composition, short-term (4-wk) studies were conducted in rats, mice and hamsters fed either a cereal-based diet or the AIN-76A purified diet supplemented with vitamins and minerals at the highest recommended levels for each of the species used. Although the purified diet was more palatable to rats and showed a higher protein quality, growth rate and food intake were generally slightly higher with the cereal-based diet in each of the species examined. The haematological values of the two diet groups were generally comparable. On the cereal-based diet the production of faeces was considerably higher than on the purified diet and was accompanied by a higher weight of the caecum. These findings were attributed to the relatively high level and mixed composition of the fibre fraction in the cereal-based diet. Blood levels of cholesterol and phospholipids were clearly lower on the cereal-based diet than on the purified diet. Because the differences were probably due to the level and composition of the fibre fraction, they support the suggestion to replace the 5% cellulose of the AIN-76A diet by a higher level of a more composite but well defined source of dietary fibre.


Dose-dependent effects of dietary phytosterol on epithelial cell proliferation of the murine colon. Phytosterols are a group of compounds in plants that have been found to inhibit tumour development and decrease enhanced colonic epithelial cell proliferation in carcinogen-treated rats. The mechanism by which phytosterols may inhibit tumour development and alter cell proliferation is unknown. However, studies have shown that dietary phytosterol intake may alter levels of certain promoters in the colonic lumen, leading to altered levels of colonic epithelial cell proliferation. In this study, the effect of dietary phytosterol on the proliferative status of the intestinal epithelium was investigated in mice. Inbred C57B1/6J mice were fed semi-synthetic diet (control); 0.1% cholic acid, 0% phytosterol (cholic acid control); and cholic acid plus 0.3, 1.0 or 2.0% phytosterol. Dietary cholic acid significantly increased colonic epithelial cell proliferation and the highest labelled cell position by 92 and 35%, respectively. Phytosterol significantly reduced the enhanced labelling index and the position of the highest labelled cell in a dose-dependent manner. Mitotic index was also reduced significantly by phytosterol but not in a dose-dependent manner. The results of this study indicate that phytosterol influences the colonic epithelial cell morphometrics, that are important preneoplastic events in colon carcinogenesis, and may thus contribute to a reduced risk of cancer.


Proteins and amino acids as scavengers of nitrite: inhibitory effect on the formation of nitrosodimethylamine and diazoquinone. Protein and its components in high concentrations similar to those found in the digestive tract effectively scavenged nitrite and thus inhibited the formation of mutagens from nitrite. Various amino acids at 100 mM, bovine serum albumin (BSA) and trypsinized casein at 100 mg/ml effectively decreased the nitrite level of 50 mM-nitrite solution at pH 3 and 37 degrees C. Most, but not all, amino acids can convert nitrite into nitrogen gas; Pro can be converted into non-mutagenic nitrosoproline, CySH to S-nitrosocysteine, Trp to weakly mutagenic nitrosotryptophan and Tyr to non-mutagenic diazotyrosine. BSA was cross-linked, probably owing to the reaction of Tyr and Lys residues. Most amino acids inhibited more than 50% of nitrosodimethylamine formation in the reaction between 200 mM-dimethylamine and 50 mM-nitrite at pH 3 and 37 degrees C; BSA inhibited 50% of nitrosodimethylamine formation, and trypsinized casein, 100%. Most amino acids inhibited more than 50% of p-diazoquinone formation in the reaction between 25 mM-phenol and 100 mM-nitrite at pH 3 and 37 degrees C; BSA inhibited 80%, and trypsinized casein, 95% of such formation. Trypsinized casein effectively inhibited the development of the mutagenic effects attributable to the formation of diazobamethan from bamethan and nitrite.


Genotoxicity studies of the food additive ester gum. Ester gum (EG) is used in citrus oil-based beverage flavourings as a weighting or colouring agent. In the present study, concentrations of 50, 100 and 150 mg/kg body weight were administered orally to male Swiss albino mice, and sister chromatid exchange and chromosomal aberration were used as the cytogenetic endpoints to determine the genotoxic and clastogenic potential of the food additive. Although EG was weakly clastogenic and could induce a marginal increase in sister chromatid exchange frequencies, it was not a potential health hazard at the doses tested.


Effects of isopropanol on the development of inflammatory reactions in rats. The effects of isopropanol on the development of inflammation were studied in rats. Isopropanol inhibited both the histamine-induced increase in cutaneous vascular permeability and the carrageenan-induced plasma exudation into the pleural cavity. The lipopolysaccharide-induced leucocyte emigration into the subcutaneous pouch was unaffected by isopropanol, but the leucocyte emigration of carrageenan-induced pleural inflammation was markedly inhibited by isopropanol. In contrast, when isopropanol was administered with an anti-inflammatory drug (indomethacin or dexamethasone), it enhanced the pleural inflammatory reaction. These results suggest that isopropanol may exert toxic effects through interference with the normal processes of inflammation and interaction with other agents that affect inflammatory reactions.


A compilation of genotoxicity and carcinogenicity data on aromatic aminosulphonic acids. A review is presented to evaluate existing information on genotoxicity and carcinogenicity testing of various aromatic aminosulphonic acids (AASAs). A great variety of water-soluble azo dyes can form aromatic phenyl- or naphthyl-aminosulphonic acids by chemical and enzymatic reduction. AASAs are also used as intermediates in the synthesis of azo dyes and azo pigments and can arise as contaminants in the final products. Comparisons have been made with the data available on the corresponding unsulphonated analogues, some of which are known to be genotoxic and/or carcinogenic. The vast majority of the AASAs were conclusively non-mutagenic in the Ames test. In most cases the absence of genotoxicity was also demonstrated with a variety of other test systems in vitro and in vivo. It is concluded that AASAs, in contrast with some of their unsulphonated analogues, generally have no or very low genotoxic and tumorigenic potential.


[Spontaneous dissection of the internal carotid artery]. A typical case history of spontaneous dissection of the internal carotid artery is presented. In young patients with cerebral ischemia, initial pain in the affected side of the head and neck, a possible provocative mechanism and a transient or even persistent Horner's syndrome are highly suggestive. The angiographic picture of carotid artery dissection is characteristic. Spontaneous resolution is common, and recurrence rare. Surgical treatment can therefore be reserved for individual cases with recurrent ischemia and caused by emboli originating in the dissected segment of the artery.


The experience of bereavement in caregivers of family members with Alzheimer's disease. This paper reports an analysis of the bereavement experience described by 13 caregivers of family members with Alzheimer's disease. Utilizing the constant comparative method, four patterns of experience and two major concepts describing bereavement were identified. Two stages of bereavement are described: The first during caregiving and the second following the death of the family member. Findings support the need for professional intervention for caregivers during the caregiving period, which may also be a time of intense bereavement.


Men's views about hysterectomies and women who have them. Men's (N = 25) views about the effects of hysterectomy on women and on their relationships with women they knew who had experienced hysterectomies were solicited by interviews. Many men were not knowledgeable about hysterectomy. They perceived negative psychological, social and sexual effects of hysterectomy on women; but they did not think hysterectomy affected their relationships with women. However, they also communicate very little with women or health care professionals about hysterectomy.


Health policy dilemmas related to high technology infertility services. As cost containment in health care becomes an important concern, the costs and benefits of specific health care services will be more closely examined. The costs and benefits of one type of health care, high technology infertility services, are explored in this paper. These services may be particularly susceptible to cost containment since they are costly, raise ethical issues, and because they currently are provided to healthy individuals not experiencing life-threatening illness who can afford them.


Ethical concerns in a long-term tube feeding study. Five ethical concerns about decision-making in relation to tube feeding were determined through secondary analysis of findings from a chart review study examining long-term tube feeding practices. The five ethical concerns are: (1) who should make the decision to tube feed? (2) how should tube feeding decisions be made? (3) what are valid reasons for initiating and continuing tube feeding? (4) is it permissible to withdraw tube feeding once it is initiated? and (5) is tube feeding an effective and appropriate life supporting technology? Ethical concerns are described, using examples from research data. Implications for health care follow.


Functional status outcomes of a nursing intervention in hospitalized elderly. This paper examines the effectiveness of a nursing intervention for elderly hospitalized patients (N = 235) as measured by functional outcomes. A nursing intervention targeted at factors which influence acute confusion or delirium employed strategies to educate nursing staff, mobilize patients, monitor medication and make environmental and sensory modifications. Subjects who received the intervention were more likely to improve in functional status from admission to discharge than subjects who did not receive the intervention.


Conceptualizing psychological well-being in cognitively-impaired older persons. This article addresses a neglected area within nursing knowledge development: appropriate conceptual frameworks for guiding care of institutionalized, cognitively-impaired elders. Following a review of possible conceptual frameworks, psychological well-being, as defined by Lawton (1983), is proposed as an appropriate framework for guiding knowledge development and care of this elderly population. Two aspects of psychological well-being, positive and negative affect, may be appropriate indicators of the concept in cognitively-impaired elders. Instruments for measurement of psychological well being are also discussed. The implications of using psychological well-being as a conceptual basis for both research and nursing care are presented.


Postpartum depression: a nursing perspective on women's health and behaviors. Postpartum depression is examined from different disciplinary perspectives including obstetrics, psychiatry, psychology and nursing. These perspectives are compared in relation to knowledge development, research designs and interventions for clinical practice. Nursing's contributions to understanding women's health and behaviors are highlighted in three areas: exploring women's experiences with symptoms of depression; delineating the character of women's affective changes during childbearing; and further study of another form of symptom distress conceptualized as dysphoria. Three alternative hypotheses are presented as new directions for future nursing research.