Clostridium botulinum in soil on the site of the former Metropolitan (Caledonian) Cattle Market, London. Sixty soil samples were collected from the redeveloped site of the former Metropolitan (Caledonian) Cattle Market, Islington, London. Of these, 15 (25%) contained Clostridium botulinum and no less than four types (B, C, D and E) were demonstrated. Early British soil surveys suggested that only 4--8% of samples contained Cl. botulinum (type A or B). Although there can be no absolute proof, it seems likely that the striking prevalence at the Market site was the result of faecal contamination by a small proportion of the many millions of farm animals brought there from elsewhere. The distribution of Clostridium tetani was uneven, but of 18 soil samples taken from one area of the Market site, 16 (89%) were positive.


[The antibacterial activity of amniotic fluid with a correlation between zinc phosphorus concentrations (author's transl)]. Antibacterial activity of 22 amniotic fluids collected at different stage of pregnancy have been tested against different types of staphylococci: 209 P, 2961 and Escherichia Coli OMS and 83. At the same time zinc and phosphorus concentration in these fluids have been measured. 77 p. 100 of those fluids present an antibacterial activity, but no correlation has been found with their concentration in zinc and phosphorus. Probably this activity is multifactorial and further studies need to be done to identify the factor or factors responsible for that antibacterial activity.


[Bret's plastic operation on the uterus (author's transl)]. A comparison of our results with those in the literature confirms that Bret's plastic operation on the uterus is valuable in the cure of septate uterus with two cavities in infertile patients who have had several spontaneous abortions. In spite of this it is advisable to take care to select cases and to be guided by the classical indications for plastic operation on the uterus. The number of abortions (more than 2) is the major criterion but it is often difficult to confirm that the infertility which results is due to the malformation and not to associated pathology. The problem is even more complex when it is a question of sterility rather than repeated abortions.


Bacteriostasis of Escherichia coli by milk. III. The activity and stability of early, transitional and mature human milk collected locally. Milk from 150 local mothers has been assayed for bacteriostatic activity for milk-sensitive and milk-resistant indicator strains of Escherichia coli. Activity is greatest in colostrum which is active directly against all strains of E. coli. One week after delivery of the baby, milk is active against the milk-sensitive strain and becomes active against the milk-resistant strain in the presence of physiological amounts of bicarbonate and iron-binding protein. This activity decreases within 2--4 days on keeping milk unheated at 4 degrees C but is preserved for at least 4 months and often up to 2 years in milk heated to 56 degrees C then stored at 4 degrees C or in milk frozen, unheated, at -28 degrees C provided it is not repeatedly thawed and frozen. Later lactation milks are usually indistinguishable in activity from 1-week post-partum milk but may be less stable on storage particularly if frozen. Lyophyilization in vacuo preserves activity of early-lactation milk for at least 6 months. Heating milk to above 65 degrees C causes a progressive loss of activity which can be partially restored by adding bicarbonate and iron-binding protein. Iron abolishes the activity of milk and reduces that of colostrum.


Bacteriostasis of Escherichia coli by milk. IV. The bacteriostatic antibody of human milk. Bacteriostatic activity for milk-sensitive and milk-resistant strains of Escherichia coli is reduced when IgA is removed from milk by precipitation. Lysozyme is not involved in bacteriostasis and can be removed without loss of activity; heavy bentonite absorption however removes some lactoferrin causing partial loss of activity. The heat-labile antigen eliciting bacteriostatic antibody for E. coli is present in milk-sensitive and milk-resistant strains and in some other Enterobacteriaceae, e.g. salmonella; it cross reacts with the antigen in others, e.g. proteus and enterobacter. The antibody is therefore likely to be present in all human milk as a result of the normal commensal gut flora and with widespread activity.


Microbial contamination of pharmaceutical products in the home. One thousand, nine hundred and seventy-seven pharmaceutical products used in the home were examined for microbial contamination. Viable micro-organisms were recovered from 14.0% of samples. Medicines used in the home are apparently not exposed to the same opportunities for contamination as those used in hospital.


The effect on the virulence and infectivity of Salmonella typhimurium and Salmonella gallinarum of acquiring antibiotic resistance plasmids from organisms that had caused serious outbreaks of disease. Antibiotic resistance plasmids from organisms that had caused serious epidemics, including those responsible for epidemics of chloramphenicol-resistant typhoid fever and dysentery in Central America, were transferred to a strain of Salmonella typhimurium and of Salmonella gallinarum. The virulence and infectivity of these R(+) forms were then compared with the R(-) parent forms in orally inoculated chickens.None of the R(+) forms were more virulent than their R(-) parent forms. The mortality rates they produced were either the same as or less than that of their R(-) parent forms. The mortality rates were not increased by feeding the chickens on diets containing antibiotics against which the plasmids provided resistance.The removal of the plasmids from some R(+) forms of decreased virulence was not accompanied by any alteration in virulence, indicating that they were less virulent mutants of the parent strain that had conjugated preferentially. In other cases their virulence was increased, indicating that the very possession of the plasmid was involved in their decreased virulence. Of four forms of the S. gallinarum strain harbouring the plasmid that had been incriminated in the Central American dysentery outbreak, one was as virulent as the parent R(-) form and the other three were less virulent. Preferential conjugation by an avirulent mutant was responsible for the lack of virulence of one of them but the very possession of the plasmid appeared responsible for the decreased virulence of the other two. The decreased virulence of de-repressed F(+) and I(+) forms of the S. typhimurium strain was increased to that of repressed F(+) form and of the parent form by plasmid removal.Organisms of the R(+) forms of the S. typhimurium strain were not excreted in larger amounts or for longer periods of time by infected chickens than organisms of the R(-) parent form were. Neither did organisms of the R(+) forms of this strain or the S. gallinarum strain spread more rapidly or more extensively from infected chickens to in-contact chickens than organisms of the R(-) parent forms did. When antibiotics against which the infecting R(+) organisms provided resistance were included in the diet of these chickens the R(+) organisms were usually excreted in greater amounts, for longer periods of time and spread more rapidly and more extensively from the infected chickens to the in-contact chickens.


The distribution of plasmids determining citrate utilization in citrate-positive variants of Escherichia coli from humans, domestic animals, feral birds and environments. Sixty-seven isolates of citrate-positive variants of Escherichia coli were isolated from human, domestic animal, feral bird and environmental sources. With the exception of citrate utilization, all isolates were identified as typical E. coli by their biochemical reactions. The transmission of the ability to utilize citrate on Simmons' citrate agar was demonstrated in 53 (79.1%) out of the 67 citrate-positive E. coli variants obtained from various sources. Drug resistance determinants and citrate utilizing character were co-transmitted into E. coli K-12 by conjugation among citrate-positive E. coli isolates carrying R plasmids except for that isolated from horses. The other characters (haemolysin or colicin production, raffinose or sucrose fermentation) were not transmitted together with the citrate utilizing character. These facts suggested that the structural gene responsible for citrate utilizing ability in citrate-positive variants of E. coli was located on a conjugative plasmid.


A solid-phase enzyme linked immunosorbent assay for the detection of African swine fever virus antigen and antibody. A solid-phase enzyme-linked immunosorbent assay was developed to measure both African swine fever virus (ASFV) antigen and antibody. Experiments showed it to be reproducible and able to detect limiting antigen concentrations of 50--500 HAD50/ml. The assay was more sensitive than those used at present to detect ASFV antibody and it is suggested that it might be of great diagnostic use in countries where African swine fever has recently appeared.


Murine B cell leukemia (BCL1): organ distribution and kinetics of growth as determined by fluorescence analysis with an anti-idiotypic antibody. The life history of a transplantable B cell leukemia (BCL1) that arose spontaneously in a BALB/c mouse is described. Animals bearing this tumor live from 2 to 4 months in apparently good health despite massive splenomegaly and leukemia. Antibody to the idiotype or gamma light chain of the tumor IgM was used in conjunction with the fluorescence-activated cell sorter to identify tumor cells in the BCL1-bearing mice. The results suggest that these cells multiply and differentiate in the spleen and subsequently emigrate to the blood. Tumor cells do not recirculate as evidenced by their failure to enter the thoracic duct or to infiltrate lymph nodes to a significant extent. During tumor growth, a population of T cell blasts appears that may be involved with an immune response against the tumor.


Functional characterization of mouse T lymphocytes with IgM-Fc receptors. I. Studies on ADCC and helper cell function. The function of mouse T lymphocytes with receptors for IgM-Fc was analyzed by using immunofluorescence and a column separation method. The cellular uptake of FITC-IgM was inhibited with unlabeled Fc5 mu. IgM-FcR+ cells were active in ADCC against IgM-sensitized target cells, but not against IgG-coated target cells. The cells mediating ADCC with IgM antibody were shown to be distinct and physically separable from those mediating ADCC with IgG antibody. Helper T lymphocytes for humoral antibody formation in a hapten-carrier system were shown to be IgM-FcR+ and Fc-IgG-.


Maturation of bursal stem cells within allogeneic or syngeneic bursal microenvironment: acquisition of postbursal maturity. Differentiation of bursal stem cells in an allogeneic or syngeneic bursal microenvironment was compared. Bursal stem cells were transplanted into CY-treated 4-day-old recipients and permitted to differentiate in these hosts for 6 weeks. Their maturity degree was thereafter assessed by transplanting them into secondary recipients by using morphologic and functional criteria. As the secondary recipients 4-day-old CY-treated or CY-treated and surgically bursectomized chicks were used. The results obtained demonstrate that bursal stem cells develop to mature postbursal cells also within an allogeneic bursa. They also indicate that although the interaction of different lymphoid cells requires histocompatibility, the interaction between stromal cells in the bursa and lymphoid progenitors is not genetically restricted.


Surface Ig isotypes on cells responding to lipopolysaccharide by IgM and IgG secretion. Using the fluorescence-activated cell sorter (FACS), we have investigated the Ig isotypes present on murine B cells, which can be polyclonally activated by lipopolysaccharide (LPS) in low cell density cultures. The LPS response was partly inhibited as a result of staining with anti-IgD and anti-IgM reagents, but not with anti-IgG reagents. The IgM+, IgD+, or IgG- fractionated cell populations gave both an IgM and an IgG response comparable to controls, whereas the response of the IgM-, IgD- cells was 5- to 20-fold lower. IgG- cells separated 1 day after LPS stimulation could still mount an IgM and IgG response indistinguishable from controls at the peak of the response. It is concluded that IgM+, IgD+, IgG- cells constitute the major LPS-sensitive cell population in the low cell density culture system and that IgG is not a necessary cell surface isotype for precursors of IgG-secreting cells.


Mobility and density of AgB, "Ia", and Fc receptors on the surface of lymphocytes from young and old rats. Analysis of spleen cell populations from old Lewis rats (greater than 24 months) and from young Lewis rats (3 to 4 months) in a fluorescence-activated cell sorter indicated that with aging there is a loss of brightly stained Ia and Fc receptor- (FcR) positive cells. The density of AgB, Ia, and FcR was diminished on the surface of cells from old rats. The rate of capping of all three membrane proteins was slower on cells from old rats. Colchicine treatment allows capping of AgB with a single ligand only in young rats. Fluorescence photobleach recovery experiments (FPR) show that the fluidity of the lymphocyte membrane from old rats is diminished and the lateral diffusion of AgB is decreased. The colchicine and FPR experiments suggest that the changes in capping in old rats are due to, in part, alterations in membrane fluidity and cytoskeletal function.


Macrophage stimulation by bacterial lipopolysaccharides. III. Selective unresponsiveness of C3H/HeJ macrophages to the lipid A differentiation signal. Peritoneal macrophages from the endotoxin-unresponsive C3H/HeJ substrain of mice were entirely refractory to activation in vitro by protein-free LPS, a defect that was not overcome by co-culture of spleen cells from the responder C3H/St substrain with LPS resistant C3H/HeJ macrophages. The defect in responsiveness appears confined to the lipid A activation signal since C3H/HeJ macrophages were fully activated after in vitro treatment by lipid A protein (LAP)--LPS complex, isolated LAP, and BCG. Moreover, after exposure to allogeneic tumor cells in vivo, C3H/HeJ macrophages were cytotoxic for tumor target cells in vitro. By contrast, macrophages from the responder C3H/St strain were fully activated by protein-free LPS to become cytolytic for tumor cells in vitro. C3H/HeJ macrophages, therefore, exhibit a highly selective defect characterized by unresponsiveness to the lipid A activation signal of protein-free LPS and resistance to the toxic effects of high concentrations of LPS that were lethal to the responder C3H/St strain.


A cell surface antigen, TER, expressed by embryos and germ cells. An antiserum prepared in rabbits against the C3HeB/FeJ mouse ovarian teratocarcinoma E6496 was absorbed in vivo in C3HeB/FeJ mice. This absored antiserum identified an antigen, denoted TER, that is present on sperm, ova, embryonic germ cells, and cells of the early mouse embryo. TER was absent from all adult somatic cells tested, but found on several murine tumors.


Effect of protease pretreatment on immunomorphologic demonstration of hepatitis-B-surface antigen in conventional paraffin-embedded liver biopsy material: quantitative evaluation. The effect of protease pretreatment on the demonstration of hepatitis-B-surface antigen by immunofluorescence (IF) and the unlabeled peroxidase-antiperoxidase technique (PAP) in conventionally processed (formalin-fixed, paraffin-emmbedded) liver biopsy material was quantitatively assessed by microphotometry. Protease digestion significantly enhances the intensity of specific staining by both methods, and, in addition, suppresses non-specific background fluorescence. The sensitivity of the immunomorphologic test is significantly enhanced, and antigen in low amounts, for example hepatitis-B-surface antigen associated with liver cell membrane ('membrane' staining), is easily detected.


Red cell-linked antibody assay for detection of antigenic markers on cell surfaces. A direct method for demonstrating antigenic markers on cell surface has been developed which makes use of the ability of bovine red blood cells coated with protein A of Staphylococcus aureus (ES) to binding IgG antibody without agglutinating. Red cell-linked rabbit IgG antibody reagents (ESA) were prepared in this way, and Ig-, IgM- and Thy-1-bearing mouse spleen and peripheral blood lymphocytes were identified by a rosette assay.


Direct tissue isoelectric focusing in agarose. We are isoelectric focusing small amounts of tissues placed directly on electroendosmosis-free agarose gels instead of using the saline extracts of tissue homogenates. More numerous proteins are extracted during isoelectric focusing of the solid tissues than present in the same tissues.


A micro method for enumerating T and B cells in mouse peripheral blood. A micro method has been devised to assess T and B cells in mouse peripheral blood. This technique permits simultaneous determination of B lymphocytes and monocytes. T lymphocytes are determined by a cytotoxicity assay. Tests require only 0.2 ml of whole blood and avoid the loss of certain cell populations secondary to flotation separation techniques. Percentages of IgM and IgG bearing B lymphocytes, Thy-1 bearing T lymphocytes as well as monocytes in mouse peripheral blood were determined in a total of 50 mice of 11 different strains.


A rapid, inexpensive and easily quantified assay for phagocytosis and microbicidal activity of macrophages and neutrophils. The objective of the present study was to develop a technique to quantitate the phagocytic and intracellular microbicidal activity in different populations of phagocytes, i.e. neutrophils and macrophages. Elicited peritoneal neutrophils and macrophages as well as alveolar macrophages and adherent splenic macrophages were used as representative cell types. The method to assess intracellular killing was based upon dye uptake and concentration by a dead micro-organism; methylene blue was used as the indicator dye and the test organism was Saccharomyces cerevisiae. Phagocytosis was measured by counting, microscopically, the number of ingested yeast (Saccharomyces cerevisiae) within the neutrophils or macrophages. A number of killed yeast, i.e., those which took up the dye, were readily visualized. The temporal pattern of phagocytosis and killing was determined concurrently. Splenic macrophages demonstrated the slowest phagocytic activity whereas neutrophils and alveolar macrophages manifested a similar phagocytic activity. Peritoneal macrophages exhibited a continuous increase in activity throughout the test period. Microbicidal activity was similar for all 4 cells types. The new technique for measuring phagocytosis and killing provides a rapid, inexpensive and easily quantified assay for assessing discrete phagocytic cell functions.


Genetic control of anti-DNP response to DNP-BSA given by continuous infusion technique. Ten inbred strains of mice were administrated with dinitrophenyl-bovine serum albumin (DNP-BSA) at a dose of 30 or 300 microgram/day by continuous infusion technique. Anti-DNP plaque-forming cells (PFC) in their spleens were assayed 10 to 12 days after the beginning of the infusion. NZB, BALB/c, C3H/He and NC strains were high responders to both doses of DNP-BSA. KK, SII and TES strains were low responders at both doses. SJL/J, C57B1/6 and DDD strains were intermediate responders: the antibody response was low to the dose of 30 microgram/day, and high to the dose of 300 microgram/day. Breeding tests between high responder BALB/c and intermediate responder DDD mice indicated that the immune response was largely controlled by a gene linked to the H-2 complex. Similar studies with high responder NZB and low responder TES mice suggested an involvement of a few genes: at least one of the controlling genes may be linked to the H-2 complex.


[Application of 4-META on adhesive opaque resin. (Part 1) Adhesive strength and the stability (author's transl)]. Mechanical devices, which has been conventionally used for retaining thermo-setting acrylic resin veneers possesses disadvantage of poor marginal sealing and requires rather complicated procedure applying on the metal casting. An application of adhesive resins to overcome these disadvantages was studied. Adhesive opaque resin consisted of MMA, epoxy acrylate, TiO2 and adhesive monomer 4-META was prepared and the adhesive bonding strength between the opaque resin and Ni-Cr alloy which is for crown and bridge works, was measured. As the results, the opaque resin applied on the metal casting with proper surface treatment showed an excellent adhesive bonding strength of 260 kg/cm2. This value did not decreased even after subjected to 300 time thermal cyclings (4 degrees C and 60 degrees C). After a three months immersion in water at 37 degrees C, adhesive bonding strength decreased slightly to 190 kg/cm2.


Physicians and the dying: a historical sketch. The tradition fo Western medicine established during the period of classical antiquity and extending through the early modern period encouraged the physician to avoid or to refuse to treat the seriously and/or terminally ill patient. The cultural environment and general attitudes toward death and dying helped to maintain this practice. Since the nineteenth century, however, the physician has increasingly accepted more responsibility, until he has become the central figure in management of the terminally ill patient. This paper examines the evolution of the relationship between the physician and the dying patient with the intention of illuminating various factors which helped to determine that relationship.


The origin of yolk-DNA in Xenopus laevis. Xenopus laevis serum and plasma was found to contain an average of 25 microgram DNA/ml. Isolated X. laevis oocytes incubated in medium containing 25 microgram DNA/ml labeled with either 125I, 32P or 14C and from three different sources (bovine, E. coli and X. laevis), incorporated the label at an average rate of 0.11 ng.mm-2.hr-1. Sucrose gradient fractionation of oocytes revealed that 40-75% of the acid-precipitable label incorporated was associated with the yolk platelets. Additional incubations of oocytes in unlabeled medium demonstrated that the DNA incorporated into the yolk platelets was undergoing turnover; only 20% of the yolk-associated DNA was still present after a one-week incubation. Our data suggest that yolk-DNA arises by the adventitious uptake of DNA present in the maternal serum by vitellogenic oocytes.


Serologic diagnosis of human infections with lymphocytic choriomeningitis virus: comparative evaluation of seven methods. The aim of this work was to compare different procedures for the serodiagnosis of human infections with the lymphocytic choriomeningitis (LCM) virus and to single out those which are both reliable and practicable. By the use of 46 sera from as many persons who had undergone infection with this virus either some time in the past or very recently and of 26 control sera, seven methods were evaluated. For making a rapid diagnosis soon after infection, determination of antibody by the immunofluorescence procedure appears to be the method of choice. Of equal reliability, though less easy to perform, is demonstration of sensitizing antibody by a plaque reduction assay, this procedure having the additional advantage of detecting antibody many years after infection, probably for life. For the demonstration of neutralizing antibody, three of four methods which were analyzed in this study gave the expected information, two employing mice, one employing cell cultures for the determination of residual infectivity. Neutralizing antibody was found to appear relatively late after infection and cannot, therefore, be recommended for the demonstration of seroconversion early in covalescence. This antibody, however, persists for many years, presumably lifelong, and is well suited to detect infections with this virus if they have occurred in the more distant past. Based on previous observations by ourselves and others, as well as on the work reported here, the complement fixation test appears to be of little value for the serological diagnosis of infection with LCM virus.


Single case study. Diazepam (Valium) detoxification. In the chronic abuser, diazepam (Valium) withdrawal can be a protracted event. In this report a case is presented of a 37-year-old Caucasian female who had been ingesting 60 to 80 mg of diazepam daily for 8 years. Twelve days following discontinuation of the drug, the patient continued to experience diarrhea, restlessness, emotional lability, and anxiety. Serial blood levels of diazepam and desmethyldiazepam were acquired and found to yield significant levels of desmethyldiazepam for 21 days and greater than trace amounts for 30 days. The results were interpreted as consistent with the slow release of the drug from peripheral storage sites. The prolonged period needed for detoxification in this patient raises important question regarding the appropriate length of hospitalization or close supervision required to withdraw the diazepam addict.


The role of blood-brain barrier transport of tryptophan and other neutral amino acids in the regulation of substrate-limited pathways of brain amino acid metabolism. Many pathways of essential neutral amino acid metabolism in the CNS are influenced by precursor availability. Since the delivery of circulating amino acids to brain cells is primarily controlled by the rate of amino acid transport through the blood-brain barrier (BBB), pathways of brain amino acid metaboliransport system. The Km of BBB transport is in the 0.1--0.6 mM range, which approximates the physiologic plasma levels and forms the basis of the unusual sensitivity of the brain to competition effects on neutral amino acid transport. Unlike the brain, the Km of amino acid transport into other organs is in the 1--10 mM range or greater, which frees these tissues from competition effects in the physiologic range of plasma amino acids. Tryptophan circulates 80--90% bound to albumin; however, the capacity/affinity ratio of the BBB neutral amino acid transport system exceeds the capacity/affinity ratio of albumin binding of tryptophan, which enables the carrier to strip tryptophan off albumin as it traverses the brain capillary. The activity of the BBB neutral amino acid transport system is probably not modulated by insulin, but is influenced by changes in thyroid hormone status; the transport system is also induced in states of hepatic encephalopathy and this induction process is the primary cause of the increased brain tryptophan and serotonin levels in cirrhosis.


Reinnervation following guanethidine-induced sympathectomy of adult rats. The reinnervation of various tissues by autonomic neurons has been studied in adult rats which had been sympathectomized by chronic guanethidine treatment (30 or 60 mg/kg/day for 8--15 weeks). In the heart, iris, ileum, mesentery, vas deferens and epididymis, fluorescence histochemistry reveals an almost complete disappearance of adrenergic fibres which is very longlasting. Even after 63 weeks few fluorescent fibres can be seen in these tissues and the density of innervation is not increased by incubation in alpha-methylnoradrenaline. The superior cervical ganglion represents an exception; large numbers of fluorescent fibres but few fluorescent ganglion cells were apparent during recovery. Axon counts carried out by electron microscopy on the vas deferens showed that after recovery for one year the number of axons was similar to that of controls; however, the pattern of innervation was abnormal, small granular vesicles were rarely seen and there was little uptake of 5-hydroxydopamine. On the basis of this evidence and of some pharmacological data it is suggested that there is a limited reinnervation by adrenergic axons accompanied by a great increase in the number of non-adrenergic, possibly cholinergic, axons.


The consequences of diaphragmatic muscle fatigue in the newborn infant. We have previously demonstrated that diaphragmatic muscle fatigue can be diagnosed in infants from spectral frequency analysis of the surface diaphragmatic electromyogram. This requires a digital computer, but the analysis takes several days. Spectral frequency changes, however, can be accurately reflected by band pass filtering and expressing the ratio of high-frequency power to low-frequency power. A fall in this ratio of greater than 20% indicates muscle fatigue. Using a simple analog device to obtain this ratio permits the results to be immediately available; we have used this method to study weaning from mechanical ventilators in ten infants. With a successful weaning step there is no significant change in the ratio, whereas an unsuccessful weaning step invariably leads to a decrease in the ratio of greater than 20%, which precedes CO2 retention and clinical deterioration. These data indicate that diaphragmatic muscle fatigue plays an important role in the infant's response to lung disease. Monitoring of the high/low frequency ratio may be helpful in weaning infants from assisted ventilation.


Intravenous trimethoprim-sulfamethoxazole in the treatment of serious infections in children. Intravenous TMP-SMZ was used to treat 19 infectious episodes in 18 patients ranging in age from 3 weeks to 13 years. Thirteen patients with various soft tissue or skeletal infections caused by Haemophilus influenzae, Streptococcus pneumoniae, Staphylococcus aureus. Streptococcus pyogenes, or Acinetobacter anitratus were successfully treated. Three children with four episodes of CSF shunt infections due to coagulase-negative staphylococci were treated successfully also. The only treatment failures were in two newborn infants with enteric gram-negative bacterial ventriculitis. TMP-SMZ was given at a daily dose of 10 and 50 mg/kg, respectively, every six hours. The drug was administered intravenously for a mean duration of 10 days (range 4 to 32); in 11 patients this was followed by oral administration for a mean of nine days (range 2 to 18). Half-life of TMP after intravenous administration was 5 1/4 hours; that of SMA was 8 1/2 hours. Levels determined three to four days after starting therapy were generally higher than levels obtained at corresponding times after the first dose. CSF/blood TMP and SMA ratios, determined in four patients, were 0.6 and 0.5, respectively. Side effects were observed in 14 patients, and neutropenia was the most common adverse reaction. Intravenous TMP-SMZ is an effective antimicrobic agent in the treatment of infections due to susceptible organisms. The frequent side effects, although reversible and of no major clinical consequence, suggest that future use of TMP-SMZ should be monitored closely.


Periodontal therapy in humans. I. Microbiological and clinical effects of a single course of periodontal scaling and root planing, and of adjunctive tetracycline therapy. The present results showed that maarked and long-lasting changes in the subgingival microflora associated with periodontal disease could be achieved by a single course of periodontal treatment. Immediately following therapy, the total number of subgingival organisms decreased 10- to 100-fold and the proportions of cultivable  Gram negative organisms and anaerobic organisms generally decreased 3- to 4-fold or more. After treatment, most periodontal pockets were populated by a scant microflora predominated by facultative Actinomyces and Streptococcus species. The kinetics of the subgingival bacterial recolonization revealed that the total cell counts and the proportions of spirochetes and Capnocytophaga species did not reach their pretreatment levels even after 6 months. Other Gram negative anaerobic species returned to pretreatment proportions after 3 to 6 months. Several Gram positive species exhibited higher posttreatment than pretreatment proportions throughout the 6 months study. The microbiological shifts paralleled significant changes in the clinical status of the periodontal tissues. Following therapy, the periodontal pocket depths decreased generally 1 to 4 mm, the gingival inflammatory index, the gingival fluid flow, and the suppurative index were generally lower, and nine of 33 test pockets examined showed apposition of alveolar bone. The microbiological and clinical changes described were exhibited by two patients treated with periodontal scaling and root planing alone and by two patients treated with the adjunctive use of systemic tetracycline therapy. In two other patients, mechanical periodontal therapy only slightly reduced the total number of subgingival organisms and the proportions of spirochetes and other Gram negative anaerobic rods. A shift in the subgingival microbial composition was achieved in these two patients after tetracycline therapy. The following model for treatment of periodontal disease is proposed: (1) Conventional therapy including thorough periodontal scaling and root planing; (2) Monitoring the subgingival flora and the clinical course; and (3) Use of antimicrobial therapy in refractory cases. Further studies are needed to develop means for rapid identification of refractory patients, and to determine the optimal antimicrobial agent, the optimal route of administration, and the optimal dosage regime.


Lyophilized bone allografts in periodontal intraosseous defects. Nine patients with 10 pairs of intraosseous periodontal defects were treated. Most of the patients had identical bilateral lesions (referred to as "mirror-image" defects). In each pair, one of the defects was randomly selected and treated as a flap and currettage control whereas the other defect was grafted with freeze-dried cortical powdered allografts of bone. Evaluation was based on radiographs, photographs, and measurements taken during both the initial surgery and at reentry approximately 1 year after transplantation. Control procedures (flap and curettage) demonstrated the same amount of osseous regeneration as that seen with the graft procedure. The amount of osseous regeneration demonstrated with the grafting procedures agreed with previously published studies. Evaluation revealed that (1) an autologous control such as incorporated in the "mirrow-image" design of this study is probably the most valid experimental model available for evaluating the clinical effectiveness of any human periodontal grafting procedures; (2) the effectiveness of freeze-dried cortical powdered bone allografts in human periodontal osseous defects is questionable and needs additional study; and (3) nongrafting procedures may be more effective in generating new attachments or reattachments in human periodontal osseous defects than previously believed.


Methods of altering crestal levels. Clinical case reports. Selected cases have been presented using different techniques to alter crestal levels. Self Regeneration or Autogenous bone grafts have been most successful in cases of three-wall and two-wall infrabony lesions. When a hemiseptal lesion occurs on the mesial of a tooth an uprighting procedure can be accomplished. When there is an adjacent tooth a forced eruption technique using orthodontic forces can be used. A surgical elevation technique has been presented which also has shown positive changes in bony topography.


Suppression of inflammation and bone resorption by indomethacin during experimental periodontitis in dogs. 1. The placement of cotton floss ligatures in a position apical to the gingival margin of premolars and molars in young dogs induced an acute inflammatory reaction in the periodontal tissues resulting in loss of connective tissue attachment and alveolar bone. 2. Bone resorption could be observed histologically within 7 days, and radiographically within 2 to 3 weeks after ligature placement. 3. Daily administration of indomethacin interfered with the periodontal tissue response to ligature placement. Indomethacin was shown to (i) delay the onset and to suppress the magnitude of the acute inflammatory reaction, and (ii) decrease the degree of alveolar bone resorption.


The experimental induction of "functionally" oriented fibers attached to cementum. Decalcified autogenous bone induced the least amount of new bone yet observed. It also apparently helped to induce the formation of functionally oriented connective tissue fibers attached to cementum. Clinical trials are indicated.


Combined orthodontic-periodontal treatment of an infrabony defect. A case report. A case presentation involving the combined orthodontic-periodontic treatment of a distally inclined mandibular left central incisor with a mesial infrabony defect is reported. Treatment was performed in three phases: (a) the tooth was moved upright (b) periodontal surgery with osseous grafting of the infrabony defect was then performed; and (c) the operative site was reentered 5 months later. The patient was followed and soft and hard tissue changes were documented for 12 months from time of initiation of treatment.


Inhibition of external pancreatic secretion by intracolonic and intraileal infusions in the cat. 1. Infusions of oleic acid into the colon or the distal part of the ileum in anaesthetized cats inhibits secretion of water and amylase by the pancreas, stimulated by secretin and pancreozymin. Intraileal infusions of other non-water-soluble substances or hypertonic solutions can also inhibit the pancreas. 2. As inhibition can be produced after extrinsic denervation of the pancreas and gut, it must in part be humorally mediated. 3. Pentagastrin-stimulated gastric secretion of acid and pepsin is also inhibited by the intraileal infusions, but the inhibition of acid secretion is less than that of pancreatic secretion. 4. It is suggested that the physiological counterpart of the inhibitory effects induced by the infusion of non-physiological solutions into the colon or ileum is an inhibition of pancreatic secretion brought about by the cessation of intestinal absorption, which marks the completion of the post-prandial digestive process.


Pancreotone, an inhibitor of pancreatic secretion in extracts of ileal and colonic mucosa. 1. Pancreotone is a polypeptide material obtained from ileal and colonic mucosa by extraction with alcohol and subsequent precipitation by bile salts. 2. In anaesthetized cats in inhibits the actions of secretin on the pancreas, and of pancreozymin on the pancreas and gall-bladder. 3. Pancreotone has a less powerful inhibitory action on pentagastrin-stimulated gastric secretion. 4. The actions of pancreotone resemble the inhibitory effects on the pancreas and stomach of intraileal and intracolonic infusions of oleic acid and other substances in cats with the vagal and splanchnic nerves cut. Pancreotone may be the humoral mediator of these inhibitory effects. 5. A possible relationship between the actions of pancreotone and somatostatin on the stomach, and of pancreotone and pancreatic polypeptide on the pancreas, is discussed.


Physical-chemical aspects of denture retention and stability: a review of the literature. The physical-chemical mechanism of retention of dentures is a highly complex one. A review of the literature suggests in addition that retention also is a personal phenomenon under the control of numerous factors. Chief among the factors involved in the retention of a well-adapted denture are the forces related to the wetting of the denture and of the mucosal surfaces and the cohesive or intermolecular characteristics of the saliva. The ill-fitting denture most often results from an increase of variation in the denture-mucosa interspace, probably due to bone resorption rather than to any major changes in the physical-chemical factors.


Minimizing postinsertion problems: a procedure for removable partial denture placement. A procedure for removable partial denture placement has been described. This procedure involves correction of pressure spots and overextensions, harmonizing of occlusion, and patient home-care instructions. Use of this procedure does not eliminate the need for postinsertion observations. Postinsertion adjustments, however, may be minimized by careful attention to each step at the placement visit.


Conservative alternative to full esthetic crowns. Several alternatives to full esthetic crowns have been presented. Preparation techniques and factors to be used in patient selection have been discussed for using all-metal esthetic retainers. Problems that arise from the indiscriminate use of full-coverage crowns must not be overlooked. Adjunctive esthetic retainers such as pinledges, three-quarter crowns, and inlays can be used to provide a functional, conservative alternative to full crowns while maintaining maximum esthetics.


Biogeometric guide to groove placement on three-quarter crown preparations. An attempt has been made to establish a practical guide to placing the grooves on a three-quarter crown which fulfills biologic, mechanical, and structural requirements. It is our intention to refine and adjust groove placement to biologic and practical limitations in the hopes of ending some of the confusion and difficulty in partial veneer preparations.


Reactive force distributions for teeth when loaded singly and when used as fixed partial denture abutments. 1. A finite element model was devised to examine mechanical responses of the periodontium to loads applied to the model in vertical, oblique, and horizontal directions for an individual tooth having varied alveolar levels, splinted teeth, and a cantilever type of fixed partial denture. 2. Forces applied to the teeth are balanced by stresses generated within the periodontal membrane and alveolar bone. 3. It was substantiated that the teeth were evolved to carry axial types of loads, since stresses on the periodontium were smaller than those obtained for oblique or horizontal types of loads. Axial types of loads produce compressive stresses on the periodontium; oblique or horizontal types of loads produce zones of compressive and tensile stresses. 4. Mechanically, splinting teeth is a desirable procedure. 5. A cantilever type of fixed partial denture should have at least two abutments. It should not be used to replace more than one tooth.


Identification of fracture zones in porcelain-veneered-to-metal bond test specimens by ESCA analysis. The ESCA technique provides a useful approach to identifying probable sites of fracture initiation in ceramic-fused-to-metal systems in which the analyzed fracture area is 1 mm2 or larger. The primary disadvantages of this technique include high equipment cost, the need for meticulous removal of superficial oxide layers formed at room temperature, and susceptibility to surface contamination by carbon, nitrogen, and oxygen. From this study the following may be concluded: 1. Judgment of the composition of any fracture surface (except that which occurs exclusively in porcelain) by naked-eye examination or optical microscopic inspection may be erroneous. 2. Generalizations on the nature of adherence zone failures for nonprecious allow-ceramic systems should not be made in the absence of fracture surface or adherence zone composition data determined by means of an acceptable analytical technique. 3. It appears unlikely that fractures originating in one of the regions of the adherence zone will have a composition analysis identical to that of metal, metal oxide, or bonding agent standards, since considerable interdiffusion or chemical interaction between these regions will have altered the original chemical compositions.


The grinding efficiency of diamond burs. Deterioration of round diamond burs during 8 minutes of operation was found to be more pronounced for burs with low particle densities than for burs with high particle density. No definitive relationship was found between the initial grinding rate and initial particle density.


Prosthodontic principles in surgical planning for maxillary and mandibular resection patients. Discussion between the surgeon and prosthodontist on surgical planning is important. It is necessary that they each be aware of the other's problems. Only in this way can continuity be established between surgical and prosthetic procedures. This will provide a maximum level of treatment for the maxillofacial patients, thereby returning them to society most expeditiously.


Plastic stopping--update.

Plastic stopping--update. Dura Seal powder and liquid and Dura Lay liquid acrylic resin materials have many uses. Methods for using these acrylic resin materials for copings, functionally generated paths, fitting crowns to clasps, centric relation stops, temporary fixed partial dentures, and porcelain additions have been described.


Relationship of the incisive papilla to the maxillary central incisors. The average distance between the most anterior point of the maxillary central incisors and the most posterior point of the incisive papilla was 12.454 mm with a standard deviation of 3.867 mm. This distance was measured when these two points were projected on a plane which was parallel to the reference plane formed by the tips of three interdental papillae; i.e., the papilla between two central incisors (A), between the first and second molars on the right side (R), and on the left side (L). The average error incurred due to inconsistency of the method employed was less than 3% or less than 0.372 mm for the position of the central incisor. It is believed that the application of this anatomic relation can provide a reliable point for arranging and checking the position of the anterior maxillary teeth for complete dentures.


Clinical progress of sealed and unsealed caries. Part I: Depth changes and bacterial counts. 1. A method for measuring depth changes in carious lesions has been developed. 2. A method for estimating bacterial viability in the study lesions has been developed. 3. Sealed cavities showed little or no change in depth over a 1-year period. 4. Open lesions showed a significant increase in depth as compared to sealed lesions. 5. Elimination or marked decrease in viable organisms under the sealant occurred.


Comparison of the retentive strength of two cast gold pin techniques. The retention contributed by the use of pins with gold castings can be substantially increased by the technique of placing a threaded pin in the dentin and making a casting with a threaded receptacle to fit the pin. The basis for the improvement is the greater retention of threaded pins to dentin compared to that of smooth, cemented pins that are part of the casting. The limitation on the retention achieved with the new technique is the cohesive strength of the cement. Zinc phosphate cement provided the highest retention, and EBA and polycarboxylate cements provided lower and similar retention when threaded pins were cemented to threaded receptacles.


The quality of restorative dental care.

The quality of restorative dental care. This study investigated the quality of restorative care in a group of health center employees. With limitations in sample size, representativeness of the sample, and methods of measuring quality clearly recognized, the results of the study suggest that significant improvements in the quality of amalgams, synthetic restorations, crowns, fixed partial denture abutments, and pontics will probably require advances in the science and technology of dentistry and modifications in the present system for delivering dental care. The impact of a quality review system is unlikely to affect the care provided by the majority of dentists. Quality review should play a role in monitoring the services fo the small percentage of dentists whose care is very inadequate. Admittedly, these conclusions are speculative and are not based on a large body of experimental information. Nevertheless, the evidence that is available is suggestive, and the development of a national policy to monitor the quality of dental care must consider what can be reasonably achieved with a quality assurance system.


A simplified approach to the complete porcelain margin. The technique described produces a metal-ceramic crown exhibiting excellent esthetic qualities and marginal accuracy superior to that achieved on the cast metal margin. A platinum foil apron or refractory dies are not necessary. A precise shoulder preparation, preferably with two master dies, is required. A chamfer with a bevel, a shoulder with a bevel, or chamfer preparations are not suited to this technique. Quantitative evaluation using a measuring microscope showed that a marginal gap on a crown fabricated on an International Bureau of Standards crown die measured 6 microns at the porcelain shoulder and from 17 to 34 microns on a gold margin of the same crown. On a prepared-tooth, rubber-base compression densite die, the marginal gap on the porcelain shoulder was 10 microns.


A radiographic technique for examination of internal defects in metal frameworks. A technique is presented which allows the dentist to evaluate metal restorations using a standard clinical radiographic machine. This technique eliminates the additional time and expense involved in using a commercial laboratory.


Ultrastructural damage to the malaria parasite in the sickled cell. The process by which malaria parasites are killed in sickled erythrocytes was studied by electron microscopy. In vitro cultures of Plasmodium falciparum in sickle cell hemoglobin (HbS) homozygous (SS) and heterozygous (SA) red cells were deoxygenated for up to 6 h and fixed under anaerobic conditions. Parasites in SS cells appeared to be disrupted by intrusions of needle-like deoxyHbS aggregates; disintegration of cytoplasm and membranes followed. In SA red cells, the parasites were generally not disrupted. Instead, extensive vacuolization occurred, a sign of metabolic inhibition. The resistance of HbS gene carriers to malaria results partly from these causes of intracellular parasite death.


Freeze-fracture study of malaria sporozoites: antibody-induced changes of the pellicular membrane. Plasmodium cynomolgi, Plasmodium knowlesi, and Plasmodium berghei sporozoites, before and after incubation with immune serum, were studied after freeze-fracture by electron microscopy. There were evenly distributed numerous intramembranous particles (IMP) on the P face of the outer membrane. The E face of the plasma membrane had fewer IMP than its P face. The E face of the intermediate membrane had few IMP and also linear arrays of slightly raised ridges running the length of the parasite. The P face of the intermediate membrane had many IMP aligned along the long axis of the sporozoite. On the P face of the inner membrane, IMP were arranged in very distinct rows conforming to the long axis of the parasite; the E face of this membrane had a few randomly distributed IMP. A prominent change in the sporozoite incubated in immune serum was the appearance of a layer of aggregated particles around the parasite. The P face of the plasma membrane had several clear areas devoid of IMP and IMP aggregates. No changes were seen in the other fractured faces of the pellicle. These observations suggest that immune serum acts only on the P face of the plasma membrane.


Acetate oxidation by bloodstream forms of Trypanosoma cruzi. Bloodstream forms of Trypanosoma cruzi had a substantial increase in respiration in the presence of acetate. Oxidation of acetate took place via the tricarboxylic acid cycle and involved an antimycin A-sensitive respiratory pathway. Oxygen uptake in the presence of acetate was a sensitive to antimycin A inhibition as was CO2 production. There was a 6--7% residual O2 uptake which was not inhibited by high antimycin concentrations. Human anti-T. cruzi sera had no effect on oxygen uptake.


The effect of gold salts on the phagocytic activity of synovial macrophages in organ culture. The effect of the gold salt, gold sodium thioglucose, has been studied on the phagocytic activity of tissue macrophages in synovium excised from patients with rheumatoid arthritis (RA) and maintained as explants in organ culture. Specimens of synovial membrane were taken for culture from synovial tissue excised from the knee joints of 22 patients with RA undergoing surgery and 14 menisectomy controls. Glass coverslips coated with yeast were placed on the synovium and the specimens maintained in organ culture. The phagocytic activity was assessed by counting the percentage of macrophages containing yeast on the coverslip removed after 24 hr in culture. The effect of gold salts was assessed by adding gold sodium thioglucose at concentrations of 3 and 30 microgram/ml to the medium, and using sodium thioglucose as an additional control. Results (means %) indicated significantly higher phagocytic activity in RA macrophages (68.6) compared with controls (40.1), p smaller than or equal to 0.001. Gold thioglucose significantly suppressed phagocytosis at 3 microgram/ml (48.0) p smaller than 0.01, and at 30 microgram/ml (47.7) p smaller than 0.02 in RA but had not effect on control synovium. Sodium thioglucose had no significant effect on phagocytosis at either concentration on RA synovium.


Gold excretion and retention during auranofin treatment: a preliminary report. Auranofin, an oral gold compound, was administered to 12 patients with rheumatoid arthritis using 2 dosage schedules (3 mg or 1 mg twice daily for 8 weeks, and then once daily for 18 weeks). In addition to outpatient clinic monitoring, all patients were admitted to a metabolic ward for 3 days for collection of 24 hr daily urine and feces. Gold content of excreta was determined by atomic absorption spectroscopy. Seventy-three per cent of the administered gold was recovered in the urine and feces of patients receiving 3 mg b.i.d., and all the gold was recovered in those taking 1 mg b.i.d. Ninety-five per cent of the recovered gold was in the feces and 5% was in the urine. These findings contrast with those observed during intramuscular (gold sodium thiomalate) chrysotherapy: 40% of the injected dose was recovered, 70% in urine, 30% in feces. Less tissue gold retention occurred with oral gold than with parenteral therapy. Following 20 weeks of auranofin (6 mg/day) chrysotherapy approximately 66 mg of gold was retained. By comparison, 300 mg of gold was retained after injectable gold sodium thiomalate treatment. The significance of these findings is discussed.


Gold and modulation of the immune response. The effects of gold on immune responses are reviewed. Gold salts used therapeutically can be followed by a decline in serum immunoglobulin levels, and rheumatoid factor titers in rheumatoid arthritis; in pemphigus there is similarly a drop in anti-epithelial antibody titers. Gold inhibits stimulation of immunoglobulin-secreting cells. Gold inhibits the activation of the classical and alternate complement pathways. Gold compounds inhibit numerous cell-mediated immune responses to various mitogens and antigens. Inhibition may be due to the effect of gold on macrophages acting as helper cell in these reactions. Auranofin is a new oral compound which seems to be particularly potent in its immuno-regulatory actions; it differs from other gold compounds in its pharmacokinetics, and in the nature of its ligand. Gold has also been reported to enhance certain immune reactions. The extent of the immuno-regulatory effects of gold in vivo is unknown, and the relation of these effects to its therapeutic actions remains to be clarified.


Synthesis and biological activity of peptide antagonists of luliberin (luteinizing hormone-releasing hormone). A series of des-His2 octa- and nonapeptide analogues of luliberin (luteinizing hormone-releasing hormone) with modifications in the 1 and 6 positions, and in some instances the 10 position, has been prepared. Some of these analogues are potent inhibitors of luliberin in vitro and in vivo. The use of ultraviolet absorption measurements for evaluating peptides containing tyrosine and tryptophan is described. An efficient synthesis of O-methyl-d-tyrosine is reported.


Hypothesis: that rheumatoid arthritis will disappear. The first unequivocally clear description of rheumatoid arthritis occurred in 1800. It is possible, however, that the disease existed in earlier times and that Emperor Constantine IX Monomachus (circa 980-1055) was a sufferer. The disease is common today in all races throughout the world. The features of rheumatoid arthritis are consistent with its being an infection, perhaps a slow-virus infection. On the basis of behaviour of other bacterial and viral infections, it is possible that we may now expect the current pandemic to disappear. Perhaps by the end of the next century it will be mild and rare or even non-existent.


Synthesis and biological activities of ftorafur metabolites. 3'- and 4'-hydroxyftorafur. Four isomers of ftorafur were synthesized as authentic samples of possible ftorafur (FT) metabolites. 2,3-Dihydrofuran was treated with perbenzoic acid in MeOH to give 2-methoxy-3-hydroxytetrahydrofuran, which upon treatment with Ac2O/pyridine yielded the key intermediate 2-methoxy-3-acetoxytetrahydrofuran. The other intermediate, 2-ethoxy-4-acetoxytetrahydrofuran, was prepared by acid hydrolysis (HCl/50% EtOH) of 1,1-diethoxy-3,4-dihydroxybutane, followed by acetylation (Ac2O/pyridine). Treatment of 2,4-bis(trimethylsilyl)-5-fluorouracil with either 2-methoxy-3-acetoxytetrahydrofuran or 2-ethoxy-4-acetoxytetrahydrofuran in 1,2-dichloroethane at room temperature using SnCl4 as catalyst afforded cis- and trans-3'-OAc-FT or 4'-OAc-FT, respectively. However, trans-3'-OAc-FT and cis-4'-OAc-FT were the major condensation products. In each case, separation of these cis and trans isomers was achieved by silica gel column chromatography. Treatment of 3'- or 4'-OAc-FT with NH3/CH3OH at 5 degrees C overnight yielded the described hydroxylated FT. Both trans-3'-OH-FT and cis-4'-OH-FT showed no significant activity against L1210 up to 100 mg/kg. These two agents produced an inhibitory effect on HeLa cell growth equal to that of ftorafur, with ID50 = 200 MICROGRAMS/KG.


Oxaprozin: a once-daily treatment regimen in rheumatoid arthritis. The development of oxaprozin provided an opportunity to evaluate the control of inflammation in rheumatoid arthritis by a drug that can be administered once daily. A double-blind 12-week evaluation suggested comparable efficacy between 1,200 mg oxaprozin given as a single daily dose and 3,900 mg ASA given in 4 equally divided doses. A lower incidence of side effects was noted in the oxaprozin group. An open 6-month study substantiated the efficacy and safety of oxaprozin.


Anticandidal activity of 5-fluorocytosine-peptide conjugates. An approach to the development of new anticandidal drugs is described that employs peptides as carriers of toxic agents into cells. 5-Flurorcytosine (5-FC) was chosen as a toxic agent with which to prepare 5-FC-peptide conjugates as models to test the carrier proposal. Model compounds were synthesized and then tested for antiyeast activity against S. Cerevisiae 9763, C. albicans 1-V, C. albicans WD 18-4, and C. Krusei 1-T. The 5-FC derivatives showed antiyeast activity comparable to 5-FC in all strains except C. krusei 1-T, in which case the compounds were less active. The solution stabilities of 5-FC conjugates at 37 degrees C were tested in the same growth medium used for susceptibility testing. The results indicated a range of stabilities where the half-life (t1/2) = 0.3--17.6 h. These results and those obtained in the susceptibility testing suggest extracellular hydrolysis and indicate that the type of linkage used to conjugate 5-FC to peptides will not provide appropriate compounds to evaluate the peptide-carrier concept.


Sexes of affected cases in sibships containing two or more members with anencephaly or spina bifida. A study has been made of the sexes of the affected within sibships containing two or more members with anencephaly or spina bifida (ASB). There is no clear evidence for variation between ASB-prone women in their propensity to bear affected cases of one sex rather than the other. It is suggested that the point should be regarded as open until further data have settled the issue.


A social-psychological perspective on successful community control of high blood pressure: a review. This review brings together studies dealing with factors that affect participation in screening, referral, and treatment for high blood pressure (HBP). Community-based screening programs are examined first, in order to describe the changing and the current distribution of hypertensives as "unaware," untreated, treated but uncontrolled, and controlled by treatment. Factors influencing this distribution are examined. Next, data on referral, acceptance of treatment, and staying in treatment are discussed, with a special reference to intervention studies. The review then brings in the broader social science literature on the psychosocial dynamics of health-maintaining and risk-reducing behaviors. The article concludes with an interpretive summary and some suggestions for further action.


The interaction of nutrition and infection: a succinct review. Malnutrition combined with susceptibility to infection threatens the health and survival of a large portion of the world's population. Of the many components of the host-parasite relation, nutrition has not received the attention it deserves. There has been increasing activity in recent years on the elucidation of the role nutritional factors play in the behavior of both host and parasite.This paper reviews the effects vitamins exert on the course of parasitic infections.


Effects of repeated exposures to peak concentrations of nitrogen dioxide and ozone on resistance to streptococcal pneumonia. Exposures to various mixtures of nitrogen dioxide (NO2) and ozone (O3) reduced the resistance of mice to streptococcal pneumonia as evidenced by increased mortality rates and shortened survival time. Daily 3-h exposures (5 d/wk) for 2--6 mo to an air pollutant mixture consisting of 940 microgram/m3 (0.5 ppm) NO2 and 196 microgram/m3 (0.1 ppm) O3 were most effective in reducing the resistance to infection. The decrease in resistance to the infection occurred sooner than the mice continued to be exposed to the air pollutants instead of clean air for 14 d after the respiratory challenge with Streptococcus pyogenes aerosol. After 3 mo of exposure to the pollutant mixture, there was some decrease in the ability of mice to clear inhalated streptococci from their lungs. At the same time the total cell count in the fluid lavaged from the lungs of mice was markedly reduced, as were the viability and phagocytic activity of the alveolar macrophages. Exposure to the pollutants combined with challenge with Streptococcus aerosol resulted in marked morphological changes in lung tissues as seen by scanning electron microscopy.


Carcinogenicity of toxaphene: a review.

Carcinogenicity of toxaphene: a review. Toxaphene is highly carcinogenic in rats and mice. Toxaphene induced malignant neoplasms of the liver in rats. Neoplasms at all sites, as well as malignant neoplasms, were increased in male and female rats ingesting toxaphene. Sarcomas were found more often in male rats and carcinomas in female rats. Neoplasms of the endocrine organs were also increased in male and female toxaphene-treated rats. The incidence of neoplasms of the reproductive system was increased in female rats, as was the incidence of mammary gland neoplasms in male rats. Toxic changes in male rats given toxaphene included interstitial fibrosis of the kidney and atrophy of the testes. Toxaphene induced malignant neoplasms of the liver in male and female mice. The incidence of malignant neoplasms at all sites was also increased. In addition to hepatic neoplasms, male mice had leukemia or lymphosarcoma and females had sarcomas of the uterus.


Muscle flap with simultaneous mesh skin graft for skin defects of the lower leg. Since 1974 we have performed muscle flap transposition (myoplasty) for the treatment of a skin loss of the lower leg with associated exposure of the bone. In order that the operative treatment may be completed in one stage, mesh skin graft was done simultaneously with muscle transfer. Twelve cases so far have been treated successfully by this procedure, the mesh skin graft taking well on the muscle flap.


Predicting fatal sepsis in burn patients. The high morbidity after severe thermal insult is believed to be related partially to a resultant decrease in immunocompetence. We tested the ability of phytohemagglutinin (PHA) and Concanavalin (Con A) to stimulate lymphocyte transformation in 17 patients with moderate to severe thermal injury (greater than 25% BSA). The patients acted as their own controls and the per cent change in their mitogen response was measured over time. Eight acutely burned patients who subsequently developed severe sepsis (Group I) had decreased ability (mean, 12% of normal) to proliferate in response to PHA, and six of these died of severe sepsis. The depressed response appeared 4 to 7 days postinjury and predated clinical evidence of sepsis by 2 to 4 days. Cells from four patients who had mild infectious complications (Group II) demonstrated greatly augmented mitogen responses (mean + 243%) approximately 7 to 10 days postinjury. Five burn patients whose clinical course was sepsis free (Group III) exhibited only minimal changes in their mitogen responses (mean +30%). Although the Con A responses of the patients' cells corresponded less to their pathology, Group I patients whose cells exhibited depressed PHA responsiveness also had diminished Con A responses. Group II patients' cells also showed increases in Con A-induced stimulation. Group III patients, who had only slightly augmented PHA responses, had minimal decreases of the Con A-induced lymphocyte transformation. Many severely burned patients develop septicemia as a result of their large wound surfaces. The appearance of decreases in mitogen-induced proliferation, however, appears to characterize those patients who will be unable to handle the septic challenge.


Efficacy of tangential excision and immediate autografting of deep second-degree burns of the hand. Fifty patients, with 71 hands affected by deep dermal burns, underwent tangetial excision and immediate autografting at a mean of the fifth postburn day. Assessment of the group at 6 weeks showed an 8% mortality, good hand function in 50%, fair function in 18%, and poor function in 24%. The total group was partitioned into patients with burns of 40% or less and those with burns of greater than 40% of body surface. The former group had significantly better hand function than the latter. Early tangetial excision with immediate autografting of deep dermal hand burns is recommedned for almost all patients with small to moderate thermal cutaneous injury. However, only after careful evaluation should patients with large, life-threatening thermal injuries be selected for this procedure.


Liquid propane cold injury: a clinicopathologic and experimental study. A case of liquid propane cold injury is described. This injury was produced by evaporative heat loss, without ignition, from skin and underlying tissues. The cutaneous appearance was that of a flame burn but underlying deep tissue damage was present. Acute vascular compromise and progressive wound sepsis were complications which required surgical intervention. A liquid propane animal model was created which defined the pathophysiology of the clinical injury. The potential for this injury exists wherever volatile liquified gases are used.


Can postmarketing surveillance help to effect optimal drug therapy? Postmarketing drug surveillance (PMS) assesses the epidemiology of drug use and monitors beneficial or harmful effects of drugs following marketing. If used systematically, PMS can substantially improve drug therapy in the United States. This can be accomplished by generating information on drug use and effects otherwise unavailable, by enabling a more efficient drug approval process, and by educating drug prescribers. However, to be successful, any PMS system will need a good deal of input from such prescribers.


Clinical trials in vaccination with leukemia associated antigens in acute myelogenous leukemia. Vaccination with purified leukemia associated antigens (LAA) was performed in sixty adult patients with acute myelogenous leukemia (AML) who were admitted to Medical City, Yermok Hospital, Alshaab Hospital, Altefelalarabie Hospital, Basrah Hospital, Mosul Hospital, Althawra Hospital and Samaon Hospital. LAA were prepared from leukemic cells, using hypotonic lysis and low frequency sonication, followed by discontinuous polyacrylamide gel electrophoresis or column chromatography. Five doses were given intradermally, after discontinuation of the maintenance therapy. Clinical and immunological studies were done prevaccination and used to evaluate the effect of this vaccine. The patients were randomized into two groups: one group included 32 patients who received LAA alone and the other group included 28 patients who received LAA with BCG-cell wall skeleton as an adjuvant. Control groups of patients were also randomized into two subgroups: one subgroup included 30 patients who did not receive any kind of immunotherapy, the other subgroup included 30 patients who received BCG-cell wall skeleton only. All the LAA vaccinated groups showed increased blastogenic response to LAA most pronounced on day 22 and afterwards. There was increased response to non-specific mitogens after vaccination, especially after the 63rd day. All the vaccinated groups showed increased skin reactivity to LAA after vaccination. Fifty-seven of these patients had an initial weak reaction but it became more marked after vaccination. There was a correlation between the blastogenic responses and skin test reactivity to the clinical course. All the nonvaccinated group and those who were given BCG-cell wall skeleton alone died within 9 weeks (range 7--11 weeks) after discontinued chemotherapy making the survival range from 23--40 weeks (median of 29 weeks), in contrast all the vaccinated groups who received LAA alone or in combination with three BCG-cell wall skeleton doses are in complete unmaintained remission ranging in survival from 58 weeks to 74 weeks (median value is 63 weeks).


Immunoassay with fluorescein-labelled antigens--device of a method and its clinical application. A simple, sensitive, highly reproducible method for assay of antibodies using fluorescein-labelled antigens according to the method by Farr is described. We measured titers of anti-BSA antibodies and antigen binding capacity of sera in BSA immunized rabbits by fluorometric assay with fluorescein isothiocyanate (FITC) labelled BSA, and obtained highly reproducible and quantitative results. The resultd times more sensitive than the results from single radial immunodiffusion. FITC-labelled double or single stranded calf thymus DNA was incubated with sera of patients with systemic lupus erythematosus and New Zealand Black mice. Both anti-double and single stranded DNA antibodies were detected in sera of systemic lupus erythematosus, but only anti-single stranded DNA antibodies in sera of New Zealand Black mice.


[Surgical treatment of complications of myocardial infarct]. Complications of myocardial infarction in the form of aneurysm of the heart, mitral incompetence and ventricular septal defect cause considerable changes in intracardiac hemodynamics which lead to severe disturbances in the circulation system in different periods after myocardial infarction. The timely and properly made diagnosis allows the prognostic severity of the complication to be appraised and the optimum therapeutic tactics determined. The given classifications of this pathological conditions promote a differential approach in considering the indications and contraindications in each case. Analysis of 312 operations shows that correction of the abnormality under conditions of extra-corporeal circulation in combination with direct myocardial revascularization is the most adequate intervention.


[Comparative evaluation of the myocardial contractile indices of the left ventricle in ischemic heart disease]. The indices of hemodynamics and myocardial contractility rate (end diastolic and end systolic volumes, ejection fraction, average rate of shortening of circumferential fibres, and average normalized rate of systolic ejection) were studied in 44 patients with ischemic heart disease to appraise the informative value of each parameter and reveal myocardial dysfunction. Calculations were done on an electronic computer system. The data obtained were compared with the findings in practically healthy persons. It was found that increase of the residual volume is the first sign of disturbed myocardial contractility and correlates well with the extent and volume of impaired contractility of the left ventricular segments. A decrease of the ejection fraction is noted only with an increase of the residual volume, the degree of the decrease correlating most closely with the degree of the decrease of the rate indices. The number and localization of the affected segments of the left ventricular wall have an effect on the contractile function of the myocardium.


Biosynthesis of basement membrane matrix by isolated rat renal glomeruli. The incorporation of radioactive precursors into the extracellular basement membrane matrix has been investigated in a purified preparation of isolated rat kidney glomeruli. Using deoxycholate extraction of isolated glomeruli which were incubated with radioactively labeled amino acids and carbohydrates, as an assay system for the measurement of incorporation of basement membrane precursors into intact deoxycholate insoluble basement membrane material, we demonstrated the in vitro biosynthesis of this structure. The assay system minimized the possibility of contamination of the isolated labeled basement membrane with labeled cell membrane fragments which may occur with the standard isolation procedures involving sonication and centrifugation. A linear incorporation of labeled proline, lysine, glycine, glucosamine, and galactose into glomerular basement membrane was shown. Basement membrane synthesis was inhibited by metabolic poisons and protein synthesis inhibitors as well as by inhibitors of collagen synthesis, but not by colchicine, an inhibitor of collagen secretion. Rhe appearance of 14C-hydroxyproline in the basement membrane matrix was negligible during the first 4 hours of incubation and rose only to 1% of the total proline counts thereafter. The results are consistent with the characterization of glomerular basement membrane synthesis and deposition as a two component system comprising a rapidly synthesized and deposited noncollagenous glycoprotein component(s) and a collagenous component which is only deposited after a delay of 4 to 6 hours.


[Orbital aspergillosis--a contribution to its diagnosis and treatment (author's transl)]. In connection with a case report, the mycological diagnosis and treatment of orbital aspergillosis are reviewed. In a 59-year-old male patient an exophthalmus on the right side could be diagnosed as aspergillosis spreading from the corresponding sinus maxillaris into retro- and peri-orbicular regions, after other causes had been excluded by differential diagnosis. In a biopsy specimen from the retrobulbar tumor, a fungal granuloma was found which, histologically and by isolation of the fungus, could be identified as an infection by A. fumigatus. Because of the good visus of the right eye, no exenteratio orbitae but an enoral revision of the sinus maxillaris, ethmoidal bone, and bottom of orbita was performed.--By infusions of amphotericin B and local washings with pimaricin (natamycin) in the sinus maxillaris and the region of the operation, a complete healing of the mycotic process was achieved.--Since 1 1/2 years, the patient has not had a relaps. This success of therapy was possible by exemplary cooperation of otorhinolaryngologists, ophthalmologists, pathologists and microbiologists.--In view of the prophylaxis of such infections, recent contributions to the epidemiology of aspergillosis are discussed.


The clinical and physiological aspects of tuftsin deficiency syndromes exhibiting defective phagocytosis. The tetrapeptide tuftsin (Thr-Lys-Pro-Arg) stimulates phagocytosis by blood neutrophilic granulocytes and tissue macrophages in a highly specific manner. Tuftsin is cleaved off the carrier gamma-globulin molecule as the free active form by two enzymes. One of these is in the spleen and the other on the outer membrane of the phagocyte. Congenital tuftsin deficiency usually arises when the peptide is mutated to an inactive peptide. The acquired type occurs if the spleen function is curtailed by removal or disease. Tuftsin deficiency is manifested by severe recurrent infections involving primarily the skin, lymph nodes and lungs. Therapy is limited to gamma-globulin injection along with appropriate chemotherapy.


[Acute leukemia in multiple myeloma: case histories, a review of the literature and assessment of the incidence]. The results of a follow-up study of 112 patients with multiple myeloma are presented. Three of these patients developed acute leukaemia during the respective period of clinical observation (maximum: 11 years)--one case of acute myeloblastic leukaemia, myelomonocytic leukaemia and erythroleukaemia, respectively. For estimating the incidence of acute leukaemia in the presence of multiple myeloma an extended life table method was applied. On the basis of our data this method gave a probability of 5.9% for a patient to develop acute leukaemia at any time after the diagnosis of multiple myeloma. In a statistical discussion this result is considered to confirm the assumption of a highly increased AL-risk in patients with multiple myeloma. In a survey of the literature some important data of 100 cases with the association acute leukaemia--multiple myeloma are reported.


Computer-assisted morphometric analysis for three-dimensional cell shape. Quantitative, morphometric analysis of 3-dimensional cell shape may prove to be a valuable adjunct to scanning electron microscopy and to the evaluation of epithelial transport phenomena. Therefore, to facilitate the wider use of cell shape analysis, a computer-assisted technique has been developed to supplement or replace the usually tedious and otherwise limited manual techniques previously available. The computer programs described here have been designed to run in a small laboratory computer, do not require a large amount of operator time, and are shown to provide an accuracy and efficiency not practical with manual procedures.


Immunofluorescent localization of fibronectin in the human kidney. Fibronectin is a glycoprotein shown previously to be present on the surfaces of cells, connective tissue matrices, and in extracellular fluids. Its distribution in the human kidney was evaluated by immunofluorescence methods studying 65 renal biopsies with a variety of pathologic disorders. Fibronectin was found in the mesangium of the normal kidney and increased proportionately in the disease states characterized by mesangial expansion. It was visualized in glomerular capillary loops in some biopsies with membranoproliferative glomerulonephritis, diffuse proliferative glomerulonephritis, and membranous nephropathy. Additionally, fibronectin was detected in glomerular crescents, diabetic nodules, vascular thrombi, glomerular sclerosis, and variably in the interstitium.


[Current concepts concerning the genesis of vestibulo-vegetative disorders in weightlessness]. The up-to-date hypotheses of the genesis of vestibulo-vegetative disorders in weightlessness are taken under critical analysis. Preference is given to the concept which attaches greatest importance to the changes in stereotyped interactions of analyzers responsible for space perception. It is, however, emphasized that neither hypothesis can account for all the phenomena seen in crewmembers in orbital flight. It is, therefore, indicated that mechanisms of vestibulo-vegetative disorders need further study. It is believed that the most promising line of research is to study the role of endogenous factors determining individual variations of motion sickness susceptibility.


The alcoholic personality. A reanalysis of the literature. A review of the literature suggests that the concept of "the alcoholic personality" might be usefully broken down into two concepts--a clinical alcoholic personality and a prealcoholic personality.


Anaplastic cardcinoma of the thyroid in a population irradiated for Hodgkin Disease, 1910--1960. Post-irradiation carcinoma of the thyroid is usually histologically well-differentiated. In general, those subjects who developed carcinoma had been exposed to low-to-moderate doses of irradiation for benign conditions. We reviewed the charts of 520 patients with Hodgkin's disease seen at Roswell Park Memorial Institute, and found 2 cases of anaplastic carcinoma amongst other thyroidal abnormalities. The existing reports of post-irradiation carcinoma are reviewed and suggestions are made for the management of heavily irradiated, potentially cured patients with Hodgkin's disease.


Simple method for measurement of cardiac output by thermodilution after cardiac operation. Cardiac output by the thermodilution technique was measured by a new No. 2 Fr. transthoracic (2F-TT) thermistor catheter placed at cardiac operation into the pulmonary artery directly through the right ventricular outflow tract. Cold (0 degree C) 5% dextrose in water (D5W) was used as indicator and injected through a percutaneously placed central venous pressure (CVP) catheter in the jugular vein. Comparison to the No. 7 Fr. Swan-Ganz (7F-SG) catheter demonstrated a close correlation (r = 0.87) and almost identical mean thermodilution cardiac output values during 530 determinations in 10 patients. No difficulty was experienced in insertion or removal of the 2F-TT catheter and no bleeding complications were noted. Experiments in six dogs showed that variation in position of the tip of the CVP catheter within the superior vena caval venous system and right atrium was not a critical factor in measurement of thermodilution cardiac output. The thermodilution cardiac output technique in general and the ease of insertion, as well as the small size of the 2F-TT catheter, should make this method especially advantageous in infants and small children.


Swaddling then, there and now: historical, anthropological and current practices. Swaddling is an ancient practice which has been used for many reasons in almost every country in the world. Some current investigators have noted that the inhibition of movement by swaddling seems to quiet irritable babies and this might be a useful nursing intervention.


Age-related changes in immune function of rats and the effect of long-term hypophysectomy. The effect of age on the ability of rats to raise antibodies to sheep erythrocytes and on the number of IgM plaque-forming cells in the spleen was investigated. An age-related decline in both parameters was observed. Additionally, the possibility that long-term hypophysectomy coupled with minimal replacement therapy might result in a delay and/or reversal of the age-related decline in immune function was studied. It was observed that long-term hypophysectomized rats responded better to immunization with sheep erythrocytes than did their age-matched unoperated littermates. The possible relationship of this to aging is discussed.


Pathology: the evolution of a specialty in American medicine. The historical evolution of pathology as a full-time specialty in medicine is viewed as a response of pathologists to changes in the level and pattern of demand for their services. The development and decline of morphologic pathology, changes in academic pathology and the evolution of clinical pathology from a medical specialty to an industry with an extensive division of labor are all examined in this perspective. It is shown that pathology as a medical specialty is most successful within a limited range of demand, neither too low to support full-time specialization nor too high to lead to deprofessionalization through routinization of the work activities of pathologists.


[Antibiotic treatment of pneumococcal meningitis (author's transl)]. Pneumococcal meningitis, which represents the third in frequency among the purulent forms of meningitis, continues to be, in spite of antibiotic therapy, a serious problem due to its high mortality rate, which reaches 50 per cent in patients of advanced age. The antibiotic treatment of choice is penicillin G, using chloramphenicol as the substitute antibiotic and the cephalosporins in other instances. This article is a review of the cases of pneumococcal meningitis which were admitted to our hospital in the period between 1969-1977, placing especial stress on the therapy followed. Our experience in the treatment of 28 patients affected with this condition indicates therapeutic success in 45 per cent of the cases treated with penicillin G, and a rate of 70 per cent using cephaloridine. In view of these results we believe that cephaloridine should be considered an important alternative antibiotic in the therapy of pneumococcal meningitis.


[Early ureteral complications after renal transplantation (author's transl)]. Ureteral complications occurred in 23 cases after 225 renal transplantations. The complications consisted of 17 urinary fistulas and 6 stenoses of the ureter. Fourteen of the urinary fistulas were successfully treated by conservative management. Two transplants were lost secondary to operation because of ureteral obstruction. Factors contributing to ureteral leakage were the technique of ureteral anastomosis, the handling of the donor ureter during donor nephrectomy and possibly ureteral necrosis by rejection crises. Ureteral stenosis and rejection crisis may have the same symptoms. Urinary fistulas can easily be observed by the urine extravasation. The treatment of urinary fistulas can be managed only by replacing the suprapubical drainage. The stenosis of ureter with subsequent deterioration of graft function needs an operation with the danger of loss of the transplanted kidney.


Use of an interactive teaching program to teach medical workers, about MUMPS programming. The MUMPS computer language is widely and increasingly used for medical applications. It is useful for medical students and others in the medical environment to have an understanding of such languages that can help them perform their jobs well. The author is therefore making available an interactive teaching program to instruct such people in the MUMPS computer language. Use of the teaching program is reported for 19 novice MUMPS programmers and compared with results for two experienced programmers. Free-text comments by the novices emphasize areas in which they had difficulty. There is a considerable variation in the mean time taken by the novices to answer the questions, and in the number of questions repeated because of erroneous answers. Most novices found the teaching program very helpful. A copy of the Standard MUMPS teaching program and the QUEST driver on which it is based has been sent to 24 institutions, including six in Europe and one in Japan, for further use.


An interactive computer program to teach and investigate diagnostic processing. An interactive computer program designed to present information about a patient taken from a history, physical examination and investigations is described. The application and advantages of the technique for the purposes of teaching and investigating medical (diagnostic) problem-solving are briefly discussed.


Modelling in biomechanics: an overview.

Modelling in biomechanics: an overview. The state of the art in biomechanical modelling is reviewed with specific reference being made to physical and mathematical idealizations of the human body and its segments. Scale models and anthropomorphic dummies which fall within the physical category are discussed briefly. Mathematical models which are much more prevalent and virtually synonymous with computer simulation models are then considered in two major classifications: deformable element and rigid body representations. The former include lumped parameter, discrete parameter, finite element and continuum models and are commonly used to represent the vertebral column. Examples of rigid body models of the total body response and inertial parameter variety are outlined. Finally, topics relating directly to the construction of sport and locomotion models are discussed. These include considerations for developing a static or dynamic model, utilizing Newtonian or Lagrangian equations of motion, and dealing with indeterminate systems.


[Possibilities of using lasers in medical endoscopy]. The article presents a review and analysis of publications dealing with laser use in endoscopy. Construction of light guides and laser-endoscope models are discussed intended for bleeding coagulation, neoplasm destruction and stimulation of regenerative processes in pathologically changed tissues.


Insulin deficiency and insulin resistance interaction in diabetes: estimation of their relative contribution by feedback analysis from basal plasma insulin and glucose concentrations. The liver and beta cells function in a negative feedback loop, which appears to have a predominant role in regulating both the basal plasma glucose and insulin concentrations. The degree of basal hyperglycemia in diabetes probably provides a bioassay of both the effect of a reduction in insulin secretory capacity and the degree of insulin resistance. A mathematic model of the interaction of insulin deficiency and insulin resistance has been constructed, based on the known response characteristics of the beta cells to glucose, and of plasma glucose and insulin control of hepatic and peripherpal glucose flux. The degree to which beta cell deficiency increases basal plasma glucose reflects the hyperbolic shape of the normal insulin secretory response to different glucose concentrations. The height of basal plasma insulin is a function of the degree of insulin resistance. From the basal plasma insulin and glucose concentrations, the model provides an estimate of the degree to which both beta cell deficiency and insulin resistance contribute to diabetes. The predictions arising from the model are in accord with experimental data in man and in animals. In normal-weight diabetics who do not have increased insulin resistance, the model predicts that more than 85% of beta cell function has to be lost for the basal plasma glucose to rise to 6 mmol/liter, but a further 5%--10% loss increases the basal plasma glucose to over 10 mmol/liter. In a third of a consecutive series of 65 newly presenting, uncomplicated diabetics, both normal weight and obese, the analysis from the model suggested that insulin resistance, rather than beta cell deficit, was the predominant feature.


Isolation and characterization of DNA repetitions carrying the chromosomal beta-lactamase gene of Escherichia coli K-12. A ColEl hybrid plasmid, pNUl, carrying the amp operon coding for chromosomal beta-lactamase was isolated from the Clarke and Carbon collection and physically mapped. The physical location of ampC within this plasmid was further deduced by in vitro cloning. By reciprocal recombination between pNUl and chromosome of two unstable beta-lactamase hyperproducing E. coli K-12 mutants a large plasmid from each mutant was obtained. The respective plasmid was physically mapped and found to contain five and two repeated DNA segments. The repetitions within each plasmid were equal in size, 9,800 bp and 11,900 bp respectively and were organized in tandem. The end points of the repeats were different in the two plasmids but shared a DNA segment carrying the ampC gene. The chromosomal DNA of the beta-lactamase hyperproducing E. coli mutants were found to contain an amplified DNA segment equal in size to the repeated unit found in the respective plasmid. The data shows that up to 10 identical repeats organized in tandem can be generated by a normal mutation frequency in E. coli.


Relief of polarity in E. coli depleted of 30S ribosomal subunits. Escherichia coli was depleted of ribosomes by a thermal shock at 47 degrees C which quantitatively destroyed the 30S ribosomal subunits. During recovery in minimal medium at 30 degrees C RNA is synthesized while protein synthesis resumes only after about 90 min. It is shown that lac mRNA is synthesized in the complete absence of ribosomal activity and hence RNA synthesis is not coupled to protein synthesis. Lac mRNA from a series of lac nonsense mutants was examined in both heated and untreated cells. It was found that the polar effect of nonsense mutation is relieved in the absence of ribosomes and that this relief is due to the synthesis of larger mRNA molecules. Since Rho remained active in thermally treated cells, premature termination at secondary signals within the lac operon must also depend on the presence of active ribosomes.


Synthesis and degradation of lac mRNA in E. coli depleted of 30S ribosomal subunits. Escherichia coli was depleted of active ribosomes by a thermal shock at 47 degrees C which quantitatively destroyed the 30S ribosomal subunits. During recovery, RNA is synthesized while protein synthesis resumes only after about 90 minutes. It is shown that lac mRNA is synthesized in the complete absence of ribosomal activity and hence RNA synthesis is not coupled to protein synthesis. Transcription time and average transcript length were slightly less than in untreated cells. lac mRNA was degraded much more slowly in bacteria depleted of ribosomes. In E. coli W both functional half life (T 1/2 = 28 min vs. 2.25 in untreated cells) and chemical stability. The analysis of rna and pnp mutants showed that polynucleotide phosphorylase is involved in lac mRNA degradation in heat treated cells but that RNase I is not. The functional T 1/2 was increased in pnp mutants and was 95 min during the recovery period. The rate of chemical decay is so slow that the half-life cannot be accurately determined.


Isolation and characterisation of a strain of Saccharomyces cerevisiae deficient in in vitro RNA polymerase B(II) activity. Two hundred strains of Saccharomyces cerevisiae temperature sensitive for RNA synthesis were selected and screened in crude extracts for DNA-dependent RNA polymerase activities. One strain was isolated which had only residual in vitro RNA polymerase B activity. In normal growth conditions total RNA, poly A+ RNA and protein synthesis were indistinguishable from those of the wild type strain at 23 degrees C and after shift to 37 degrees C. A temperature sensitive phenotype was detected only when rpoB containing strains were grown in adverse conditions. The mutant character showed mendelian segregation and was coexpressed with the wild type character in heterozygous diploids. Residual enzyme activity was characterised in crude extracts using synthetic polymers and natural templates in different ionic conditions.


Biogenesis of mitochondria 51: biochemical characterization of a mitochondrial mutation in Saccharomyces cerevisiae affecting the mitochondrial ribosome by conferring resistance to aminoglycoside antibiotics. An examination of the effect of the aminoglycoside antibiotics paromomycin and neomycin on mitochondrial ribosome function in yeast has been made. Both antibiotics are potent inhibitors of protein synthesis in isolated mitochondria. With isolated mitochondrial ribosomes programmed with polyuridylic acid (poly U), the drugs are shown to inhibit polyphenylalanine synthesis at moderately high concentrations (above 100 microgram/ml). At lower concentrations (about 10 microgram/ml), paromomycin and neomycin cause a 2-3 fold stimulation in the extent of misreading of the UUU codons in poly U, over and above the significant level of misreading catalyzed by the ribosomes in the absence of drugs. Comparative studies have been made between a paromomycin sensitive strain D585-11C and a mutant strain 4810P carrying the par l-r mutation in mtDNA, which leads to high resistance to both paromomycin and neomycin in vivo. A high level of resistance to these antibiotics is observed in strain 4810P at the level of mitochondrial protein synthesis in vitro. Whilst the degree of resistance of isolated mitochondrial ribosomes from strain 4810P judged by the inhibition of polyphenylalanine synthesis by paromomycin and neomycin is not extensive, studies on misreading of the poly U message promoted by these drugs demonstrate convincingly the altered properties of mitochondrial ribosomes from the mutant strain 4810P. These ribosomes show resistance to the stimulation of misreading of the codon UUU brought about by paromomycin and neomycin in wild-type mitochondrial ribosomes. Although strain 4810P was originally isolated as being resistant to paromomycin, in all the in vitro amino acid incorporation systems tested here, the 4810P mitochondrial ribosomes show a higher degree of resistance to neomycin than to paromomycin. It is concluded that the parl-r mutation in strain 4810P affects a component of the mitochondrial ribosome, possibly by altering the 15S rRNA or a protein of the small ribosomal subunit. The further elucidation of the functions in the ribosomes that are modified by the parl-r mutation was hampered by the inability of current preparations of yeast mitochondrial ribosomes to translate efficiently natural messenger RNAs from the several sources tested.


Post-translational modification of Escherichia coli ribosomal protein S6. Escherichia coli has multiple forms of ribosomal protein S6, differing in number of glutamyl resideus at the C-terminal end. Three forms are revealed when crude cell extracts are fractionated by a two-dimensional gel electrophoresis technique. Pulse-chase experiments show that the shortest and most alkaline form of S6 is the first to appear. In about one doubling time this form reaches equilibrium with the two other forms of S6, implicating the existence of an enzyme, which adds glutamic acid residues to S6. We show that the relative levels of these three S6 forms are not affected by the growth rate of the culture.


Restriction enzyme analysis of the plasmid ColIb DNA. Plasmid ColIb (61.5 Mdal) was digested with restriction enzymes EcoRI and HindIII. The DNA digestion products were separated by electrophoresis on 1.2% agarose gels. There were identified 22 fragments of ColIb DNA generated by the endonuclease EcoRI and 21 fragments produced by HindIII. Molecular weights of the fragments were estimated. The total molecular weight of the fragments generated by EcoRI was 61.42 Mdal and for HindIII fragments 62.79 Mdal.