Immunohistochemical localization of pyruvate kinase isoenzymes in chicken tissues.

A method for the localization of pyruvate kinase isoenzymes type L, M2 and M1 in tissue sections is described. Mono-specific antibodies directed against isoenzymes of pyruvate kinase from chicken and the peroxidase antiperoxidase method were used. The following preferential localizations of the isoenzymes in chicken tissues were observed: Pyruvate kinase M1 was found in skeletal muscle. The white muscle fibers were more intensely stained than the red. Some dark muscles (e.g., anterior latissimus dorsi) and the heart muscle showed no reaction with antiserum against pyruvate kinase M1. Pyruvate kinase type L was found in the hepatocytes and in kidney cortex. Pyruvate kinase type M2 was seen in the distal tubules of kidney, in hepatocytes and sinusoidal cells in liver, in lung, adipose tissue, and in the spleen mainly in the bursa dependent areas. Pyruvate kinase type M2 was detected in high concentrations in the granulation tissue of regenerating liver after partial hepatectomy. Liver sections of a hen bearing a pancreatic tumor showed an unusually high content of pyruvate kinase type M2 in some hepatocytes, which were each clustered to spots in the liver parenchyma. Thus, contrary to previous reports, the tissue distribution of isoenzymes in chicken is similar to that of other vertebrates.


[Midline granuloma. A review of the literature with particular reference to diagnostic and therapeutic problems supplemented by 3 personal case reports].

The term midline granuloma and various synonyms have been used to describe a rare lesion that ultimately forms a necrotizing ulcerating destruction of the midface. The aetiology has been variously and repeatedly discussed, and a review of the literature shows that at least three entities, which are difficult to differentiate, should be considered. Wegener's granulomatosis, malignant lymphoma and atypical histiocytic lymphoma, a disease with a pleomorphic histology, may all have an extensive necrosis and an intense inflammatory reaction. Upon the diagnosis, which is confirmed by biopsy, depends the appropriate treatment of these fatal diseases. The collective term midline granuloma should be avoided since it may delay the correct management.


Osteochondritis dissecans in the dog: diagnosis and therapy.

Osteochondritis dissecans (OCD) is a manifestation of osteochondrosis. It is thought to be a metabolic disease of cartilage maturation and endochondral ossification. Therefore, any disturbance affecting the differentiation of growth cartilage constitutes osteochondrosis. When this disturbance affects the articular cartilage so that a piece detaches, it is called OCD. Osteochondritis dissecans is well recognized but poorly understood. The etiology remains controversial. Osteochondritis dissecans is most commonly recognized in the shoulder but can occur in other areas which makes it difficult to differentiate from other disease entities. Diagnosis of OCD is based on signalment (age, breed, and sex), history, and physical and radiographic evidence. Therapy must be individualized and based on the patient's clinical signs and not on the severity of the radiographic lesion. Therapy can be effective only when applied correctly.


Characterization of methanol extraction residue (MER) from Bacillus Calmette-Guérin (BCG).

Analysis of methanol extraction residue (MER) from Bacillus Calmette-Guerin (BCG) was carried out to determine some specific chemical compositional characteristics. Samples of MER were found to contain approximately 40% protein and/or peptide, 3% soluble lipids, 17% bound lipids, 8% elemental nitrogen, and less than 2% mycolic acids. Amino acid analysis showed the presence of alanine, glycine and glutamic acid as the major amino acids. The data are reported in terms of the range found for each constituent over the samples analyzed. Somewhat consistent results were obtained between different MER preparations, but notable compositional variations were observed in samples of MER suspensions.


Stereo-specific synthesis of 3-trifluoromethylcephalosporin derivative by microbial acylase.

Cephalosporin acylase (EC 3.5.1.11) obtained from Kluyvera citrophila ATCC 21285 was found to catalyze synthesis of 7-[2-(2-thienyl)acetamido]-3-trifluoromethyl-3-cephem-4-carboxylic acid from methyl thienylacetate and dl-7-amino-3-trifluoromethyl-3-cephem-4-carboxylic acid. The enzymatically-synthesized compound showed [alpha]25 D + 42.7 degrees (c 0.058, MeOH) and its biological activity was about twice as much as that of racemic 7-[2-(2-thienyl)acetamidol]-3-trifluoromethyl-3-cephem-4-carboxylic acid chemicall synthesized. As a result, N-acylation by this enzyme was demonstrated to be asymmetric synthesis.


2-Amino-5-methyl-5-hexenoic acid, a methionine analog produced by Streptomyces sp. MF374-C4.

2-Amino-5-methyl-5-hexenoic acid (AMHA), a new methionine analog, was isolated from a fermentation broth of Streptomyces sp. MF374-C4 based on its reversal of the effect of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) in a test system that determines the size of growth zones of revertants (His+) of Salmonella typhimurium TA1535. AMHA also inhibited growth of the tester strain in a synthetic medium. These AMHA activities were abolished by methionine. The incidence of spontaneous streptomycin-resistant mutations of Escherichia coli K12 was not decreased by AMHA at concentrations where cell growth was partially inhibited. AMHA inhibited protein synthesis but not DNA or RNA synthesis in S. typhimurium TA1535 and E. coli K-12. The analog inhibited formation of methionyl-tRNA but not of valyl-tRNA in a cell-free system of E. coli, and supported ATP-PPi exchange in the cell-free system. At concentrations where it inhibited cell growth, AMHA decreased the number of foci, induced by ROUS sarcoma virus, on cultured sheets of chick-embryo fibroblasts. The effects of AMHA on focus formation and on the cell growth were overcome by methionine.


Synthesis of a tight-binding, multisubstrate analog inhibitor of gentamicin acetyltransferase I.

Gentamicin acetyltransferase I will catalyze acyl transfer from chloroacetylcoenzyme A to form 3-N-chloroacetylgentamicin. This product can be linked to coenzyme A to form a multisubstrate analog by nucleophilic displacement of the chlorine by the sulfur of coenzyme A. The analog can be purified by selective binding to cationic and anionic ion exchange resins. Kinetic analysis of a time-dependent onset and reversal of inhibition of gentamicin acetyltransferase I by the purified multisubstrate analog yields an inhibition constant of 5 approximately 20 x 10(-10) M. The inhibitor does not potentiate antibiotic activity against resistant Escherichia coli. Nevertheless, the effectiveness of the tight-binding between the enzyme and the multisubstrate analog demonstrates that inhibitors of resistance can be designed and prepared by specific enzymatic synthesis.


Inhibition of ribosomal and RNA polymerase functions by rubradirin and its aglycone.

The antibiotic rubradirin is structurally related to the ansamycin family of antibiotics. Most members of this group act as specific inhibitors of bacterial RNAP. Rubradirin and its aglycone possess diverging modes of action. Rubradirin inhibits ribosomal functions related to the peptide chain initiation process. It does not inhibit RNAP. By contrast the aglycone of rubradirin retains moderate inhibitory activity towards ribosomal functions but acts essentially as an extremely potent inhibitor of RNAP.


Inhibition of the respiratory-linked membrane potential in E. coli membrane vesicles by octapeptin.

Octapeptin is a peptide antibiotic which affects bacterial membrane structure and selective membrane permeability for protons and potassium. The influence of octapeptin on the formation of a membrane potential generated across bacterial vesicles was monitored using the Rb+-valinomycin transport system. Octapeptin inhibited the respiratory-linked generation of membrane potentials formed in the presence of succinate or Asc/PMS. In addition, the antibiotic inhibited [3H]-leucine transport driven either by succinate or Asc/PMS. These studies support the proposal that the antimicrobial activity of octapeptin is due to inhibition of the formation of a membrane potential generated in the presence of appropriate respiratory substrates.


Serum glucocorticoids, growth hormone and insulin and plasma glucose in bulls given prostaglandin E2 or F2 alpha 1.

Plasma glucose and serum insulin, growth hormone and glucocorticoid concentrations were determined in five yearling bulls given (im) 5, 15 or 30 mg prostaglandin E2 (PGE2), 30 mg prostaglandin F2 alpha(PGF2 alpha) or saline. Jugular blood was collected at frequent intervals around the time of injection and at .5--hr intervals from 1 to 9 hr after injections. Thirty milligrams PGE2 and 30 mg PGF2 alpha each caused 15- to 20-fold increases in serum glucocorticoids. Glucocorticoids increased with increasing doses of PGE2. Although PGE2 and PGF2 alpha each increased blood growth hormone, this effect was about twofold larger after PGE2. By contrast, PGE2 depressed serum insulin about 50% for 1 hr, then insulin increased about sixfold until 3 to 4 hours. Blood serum insulin increased after PGF2 alpha, but this effect only approached significance (P less than .10). Plasma glucose increased about 10 mg/100 ml after PGE2, but was not affected significantly by PGF2 alpha. Thus, the effects of PGE2 and PGF2 alpha on hormones which control glucose metabolism differ markedly. We speculate that PGE2 caused a twofold increase in growth hormone secretion within 10 to 20 min, that increased growth hormone induced increased blood glucose within 1 to 2 hr and that increased glucose caused increased insulin secretion at 2 to 4 hr, but we cannot rule out a transitory (1 hr) suppressive effect of PGE2 directly on the pancreas.


Free amino acids in blood of ruminants--physiological and nutritional regulation.

Tissue free amino acid pools account for only a small fraction of the total amino acid content in the body. Blood of plasma free amino acid pools represent only a very small proportion of tissue free amino pools. Plasma free amino acid profiles have been used as a tool to study nutritional and metabolic aspects of protein status. Static measurements of plasma amino acid levels have limited value as sensitive indicators of protein status because such measurements do not reflect the magnitude of amino acid fluxes in and out free amino acid pools. Use of plasma amino acid profiles, under well defined experimental conditions, in assessing limiting amino acids and essential amino acid requirements in ruminants is discussed.


Microcomputer controlled titration for determination of protein nitrogen in feeds and wheat.

The determination of protein nitrogen in feeds and wheat by microcomputer controlled titration is described. The method involves direct titration of ammonia with standard hypochlorite titrant in the presence of bromide. The titrant is delivered by an automatic buret, and the microcomputer controlled, automatically computed potentiometric end points are precise to 0.1% over a 5-fold concentration range of nitrogen. Digestions performed with both mercury and copper catalysts show comparable results. Samples are weighed before digestion by an electronic balance interfaced to the computer which records sample number and weight. An automatic pipet aliquots, dilutes, and buffers samples directly from the digestion tubes; the samples can be immediately titrated with the automatic titrator. The results for protein in NBS standards and check feed samples from an offical testing program compare closely with average values reported for these standards. Results show that feed and wheat samples contained 10-100% protein. Precision for successive aliquots of the same digests is 0.1-0.4%relative standard deviation; precision for multiple digestions of the same sample is 0.1-0.8%.


Studies on 30S ribosomal protein S1 from E. coli. I. Purification and physicochemical properties.

1. The distribution of ribosomal protein S1 in subcellular fractions of E. coli was determined by radioimmunoassay. It was found that about 70%, 20% and 10% of protein S1 were present in the high salt (1.0 M NH4Cl)-washed ribosomes, the ribosomal wash and the S100 fraction, respectively. 2. Protein S1 was purified from unwashed ribosomes by an improved procedure which included: (i) extraction of protein S1 from unwashed ribosomes with 1.2 M LiCl and 1.0 M NH4Cl, (ii) ammonium sulfate fractionation, (iii) two successive column chromatographies on DEAE-Sephadex, and (iv) hydroxylapatite column chromatography. Purified protein S1 was homogeneous in polyacrylamide gel electrophoresis under native and denatured conditions. 3. The molecular weights determined by sedimentation equilibrium and by SDS-polyacrylamide gel electrophoresis were 83,000 and 70,000 respectively. The sedimentation coefficient was estimated as 3.0S by glycerol gradient centrifugation. The stokes radius determined by Sephadex G-200 gel filtration was 45 A. From these data, the frictional ratio of protein S1 was calculated to be 1.65, assuming the molecular weight and partial specific volume to be 70,000 and 0.736, respectively. Protein S1 had an elongated shape with an axial ratio of approximately 8.5. 4. Protein S1 contained 2 residues of half-cystine and about 10 residues of tryptophan. From CD measurements, the contents of alpha-helix and beta-structure were estimated to be 32 and 27%, respectively. 5. As reported by Kolb et al. (1977) (Proc. Natl. Acad. Sci. U.S. 74, 2379-2383), and Draper et al. (1977) (Proc. Natl. Acad. Sci. U.S. 74, 4786-4790), the intrinsic fluorescence of protein S1 was markedly quenched on interaction with poly(U). The maximal quenching was observed when 30 mol of poly(U) (as UMP residues) was added to one mol of the protein.


Early sequential lesions during development of experimental gastric cancer with special reference to dysplasias.

The early sequential development of gastric cancer was studied with experimental animals and examined with respect to what conclusions can be drawn for understanding carcinogenesis in man. After limited oral administration of N-methyl-N'nitro-N-nitrosoguanidine to 174 rats carcinomas developed in most cases directly from the otherwise unchanged mucosa through various successive stages of transformation, without passing through a benign-appearing proliferative or neoplastic epithelial lesion. Focal dysplasia grade I was the first recognizable change observed by light microscopy, followed by dysplasia grade II, and subsequently dysplasia grade III. In spite of very similar morphological characteristics, the experimentally induced dysplasias cannot be simply equated in their etiology and biological behavior with the dysplasias of the human stomach. Dysplasias of grade I and II commonly found in man are usually associated with a chronic gastritis; they are located in the upper third of the mucosa and are for the most part reversible. The experimental dysplasias occuring in the proliferative zone of an otherwise undisturbed mucosa must be considered potentially premalignant, as they are irreversible and develop progressively. This finding points out that in man dysplasias grade III within the regenerative zone of non-inflammatory mucosa should be considered particularly as possible precursors of gastric carcinomas.


Regulation of the G1 leads to S phase transition in chick embryo fibroblasts with alpha-keto acids and L-alanine.

Temporal inhibition of protein synthesis with cycloheximide prevents subsequent insulin, but not serum-stimulated DNA synthesis in G1-arrested chick embryo fibroblasts (CEF). The inhibition is measured by the incorporation of 3H-thymidine into acid insoluble material and confirmed by chemical estimate of the DNA content of inhibited and uninhibited cells. Cycloheximide treatment is without effect if the cell cultures are maintained at 4 degrees C while exposed to the drug. Several alpha-keto acids (pyruvate, oxaloacetate, alpha-ketobutyrate) at 0.5-1 mM concentrations restore DNA synthesis in previously inhibited cells when combined with insulin. L-alanine (D-alanine is inert) is even more effective than the keto acids in stimulating DNA synthesis after cycloheximide treatment. Glucose transport was unaffected by cycloheximide treatment while lactate levels in medium from inhibited, insulin-stimulated CEF were reduced 70% compared to uninhibited counterparts. We speculate that cycloheximide treatment may lead to the decay of a glycolytic enzyme which compromises the ability of inhibited cells to synthesize pyruvate from glucose, and thus induces an exogenous requirement for alpha-keto acid or L-alanine. A serum component(s) with a molecular weight of about 100 permitted insulin-stimulated DNA synthesis in inhibited cells.


Combined microspectrophotometry and automated quantitative autoradiography applied to the analysis of the plant cell cycle.

Two methods, which relate grain number to cell cycle phase in Feulgen-stained autoradiographic preparations, have been developed and compared. Both methods automate grain number estimations, one by taking integrated absorbance measurements at different wavelengths, the other by measuring absorption at a single wavelength before and after chemical removal of silver grains. With tritium-labelled tobacco mosaic virus as a probe, a quantitative analysis has been made of the binding of virus particles to plant protoplasts in different compartments of the DNA replication and partition cycle. The preliminary results indicate that the quantity of virus bound by protoplasts is related to their cell cycle phase. Whilst in this case, the methods have been used with plant cells, both techniques are equally applicable to animal cells.


Insulin-induced receptor loss in the cultured human lymphocyte: quantitative morphological perturbations in the cell and plasma membrane.

When cultured human lymphocytes (IM-9) are exposed to 10(-6) M procine insulin for 6 h, washed, and incubated with 125I-insulin, the ability of the cell to bind the labelled hormone is reduced by a mean of 78%. Under these experimental conditions that induce insulin-receptor loss in this cell there is a mean 95% increase in microinvaginations in the plasma membrane revealed by electron microscopy on freez-fractured replicas of the cell. At the same time, horseradish peroxidase uptake, a marker of endocytosis, is increased in the cells incubated with insulin. Coupled with our recent EM autoradiographic evidence that labelled insulin is acutely internalized by this cell, these studies are consistent with the possibility that endocytosis represents a mechanism by which receptor is removed from the cell surface.


Rapid identification of Enterobacteriaceae by using noncommercial micro-tests in conjunction with API 20E profile data.

A total of 371 (97%) of 382 strains of Enterobacteriaceae representing 26 species were identified cheaply, accurately, and rapidly by using a test system based upon standard 96-well microdilution plates and the API 20E profile data.


Compatible results obtained from biotyping and serotyping in Serratia marcescens.

The correspondence between complete serotype and biotype (P.A.D. Grimont and F. Grimont, J. Clin. Microbiol. 8:73-83, 1978) of 474 Serratia marcescens strains was studied. Of 127 serotypes, 70 were represented by two or more strains of the same serotype belonged to one biotype. However, for 91% of serotypes, strains of the same serotype belonged to one biogroup--i.e., a group of closely related biotypes. Biogroups are A1 (A1a, A1b); A2/6 (A2a, A2b, A6a, A6b); A3 (A3a, A3b, A3c, A3d); A4 (A4a, A4b); A5/8 (A5, A8a, A8b, A8c); and TCT (TCT, TT). Only two serotypes were composed of a mixture of pigmented and nonpigmented biogroups. Pigmented biogroups (A1 and A2/6) were otherwise differentiated from nonpigmented biogroups (A3, A4, A5/8, and TCT) by serotyping. Some biogroups preferentially occurred in some O serogroups: A4 in 01; A2/6 in O6, O8, and O14; and A3 in O9, O12, and O15. Three H serogroups were found to be biochemically homogeneous: H1, H7, and H20 were respectively and uniquely composed of biogroups A4, TCT, and A3. A square matrix of O versus H serogroups, with the corresponding biogroup for each O X H combination, was used for comparisons between O groups and between H groups. Identical patterns of biogroups were shown by serogroups O6, O8, and O14. Taxonomical, ecological, and practical consequences of these findings are discussed.


Charcoal-yeast extract agar: primary isolation medium for Legionella pneumophila.

Charcoal-yeast extract agar is a new bacteriological medium that supports excellent growth of the Legionella pneumophila. It results from modifications made in an existing L. pneumophila medium, F-G agar. Yeast extract, instead of an acid hydrolysate of casein, serves as the protein source. Beef extractives and starch are not added. Activated charcoal (Norit A or Norit SG) is included at 0.20% (wt/vol). Comparison of charcoal-yeast extract and F-G agars showed that a greater number of colony-forming units of L. pneumophila was recovered from a standardized tissue inoculum on charcoal-yeast extract agar (4.35 x 10(6) colony-forming units) than on F-G agar (4.85 x 10(4) colony-forming units). Macroscopic colonies of L. pneumophila were visible on the new medium within 3 days, whereas 4 days of growth was required on F-G agar.


Indirect sandwich enzyme-linked immunosorbent assay for rapid detection of Haemophilus influenzae type b infection.

We report the development and testing of an enzyme-linked immunosorbent assay with excellent sensitivity for the detection of Haemophilus influenzae type b (HI(b)) antigen in clinical specimens from patients with HI(b) meningitis. The assay, an indirect sandwich technique, uses polystyrene balls as a solid phase and an alkaline phosphatase-labeled goat anti-rabbit globulin conjugate. Specimens are incubated with polystyrene balls armed with burro anti-HI(b) antiserum, and recognition antibody is visualized by addition of alkaline phosphatase-labeled anti-globulin, together with the enzyme substrate p-nitrophenyl phosphate. Concentrations of antigen are determined from standard curves prepared by using purified HI(b) capsular antigen polyribophosphate. The assay reproducibly detects polyribophosphate at concentrations between 1 and 5 ng/ml. Cross-reactions have not as yet been encountered in simulated and authentic clinical specimens containing other species including Escherichia coli, Klebsiella pneumoniae, group B Streptococcus, Pseudomonas aeruginosa, Streptococcus pneumoniae, Staphylococcus aureus, Neisseria meningitidis, and Listeria monocytogenes. In preliminary tests with 11 spinal fluid specimens, 2 serum specimens, and 5 urine specimens from patients with culture-proved HI(b) meningitis, antigen was detected in all specimens in concentrations ranging from 1 to 7,000 ng/ml. Antigen was not detected in any of 62 clinical specimens which were culture negative for HI(b), including 11 spinal fluid specimens from patients with bacterial meningitis caused by microorganisms other than HI(b). The enzyme-linked immunosorbent assay technique described here is considerably simpler than radioimmunoassay and, based on concurrent tests with 14 positive clinical specimens, may be more sensitive than counterimmunoelectrophoresis. It seems, therefore, to hold considerable promise for clinical use in rapid detection of systemic HI(b) infections.


Evaluation of the modified Micro-ID system for identification of Enterobacteriaceae.

Micro-ID is a system designed to identify the Enterobacteriaceae by utilizing reagent-impregnated disks for 15 biochemical tests. Since its initial evaluations, the system has undergone modification in formulation and in its computer data base. In a dual-center evaluation, 306 isolates of Enterobacteriaceae were tested: 145 common and typical isolates at the Mayo Clinic and 161 unusual or atypical isolates at the Center for Disease Control. Each laboratory also exchanged 50 cultures to test the system's reproducibility. Micro-ID correctly identified 142 (98%) of the common clinical isolates and 123 (76%) of the unusual or atypical organisms. However, in this latter group, three species tested were not in the system's data base. When these organisms were deleted from the analysis, 138 of 146 (95%) of the unusual or atypical isolates were correctly identified. Analysis of the 100 isolates identified in duplicate revealed 93% reproducibility of genus and species identification and 62% reproducibility of octal code numbers. Of the 31 strains with the same identification but different code numbers, 74% differed in only one biochemical test.


Hemagglutination by Escherichia coli in septicemia and urinary tract infections.

The agglutination of erythrocytes from various animal species by Escherichia coli was studied. The 405 strains of E. coli were isolated from urine in patients with urinary tract infections, from blood in septicemic patients, or from feces in persons without intestinal or urinary disorders. In urinary tract infections, d-mannose-resistant agglutination (MRHA) of human erythrocytes was the most common finding (23% of the strains). The highest frequency of mannose-sensitive hemagglutination (MSHA) attributed to type I (common type) pili occurred with guinea pig erythrocytes (11.5%). Of the 78 E. coli strains isolated from blood cultures, 11 (14%) produced MRHA of human erythrocytes and only one gave MSHA. In the stool cultures, only 1 of 170 E. coli strains was MSHA reacting, whereas 28 strains (16.5%) showed MRHA of human erythrocytes. No MRHA strain reacted with antiserum against colonization factor antigen (CFA)/I of pilus nature in enterotoxigenic human E. coli strains (O78:H12). MRHA of bovine erythrocytes, reputedly typical of enterotoxigenic E. coli of serogroups O6 and O8, was shown by only two strains, neither of which agglutinated with CFA/II antiserum. The most common hemagglutinating pattern of E. coli from urine and blood thus was MRHA for human erythrocytes. This agglutination may have been caused by pili or other surface properties of one or more serotypes. These may represent a new class of colonization-promoting antigens (adhesins).


Identification of Enterobacteriaceae in frozen microdilution trays prepared by Micro-Media Systems.

Frozen microdilution trays, with 20 different biochemical test media for identification of Enterobactericeae, were evaluated. The test panels were those provided by Micro-Media Systems (MMS), who also provided a code book for interpretation of the test results. The interpretations of the MMS test system and of the Analytab API 20E test system were compared with those obtained from tests with conventional media. Tests with 468 Enterobacteriaceae demonstrated nearly comparable results with the two commercial systems. About 6% (API) and 7% (MMS) of the isolates could not be identified without additional tests, and another 3% (MMS) to 4% (API) of the isolates gave test patterns that were not found in the code books. One to three percent of the isolates were misidentified. It was concluded that the MMS Enteric Quad Panels provide an efficient, relatively inexpensive, and reasonably accurate method for identification of the Enterobacteriaceae.


Evaluation of Micro-Media Quad Panels for identification of the Enterobacteriaceae.

The Micro-Media Quad Enteric Panel and coding system were evaluated by comparing the identifications of 193 stock and 216 clinical isolates, representing 31 species of Enterobacteriaceae, with those provided by conventional methods. The results corresponded for 91% of the organisms if only the single or most probable identification was accepted and for 93% if the correct identification was listed as one of several possible, but not the most probable, identification by the coding system. With 73% of the isolates, the single identification provided by the coding system was correct, and in 20% of instances the correct identification was listed as the first of several choices in descending order of probability but requiring additional tests for differentiation. In most of the latter instances, these additional tests consisted of serological confirmation of salmonellae or shigellae. Discrepancies consisted of incorrect identifications (4%) and organisms with code numbers not appearing in the coding system (3%).


Semiquantitative catalase test as an aid in identification of oxidative and nonsaccharolytic gram-negative bacteria.

A simple and rapid semiquantitative slide catalase test useful for the identification of oxidative and nonsaccharolytic gram-negative bacteria, i.e., "nonfermenters," is described. Using the interpretative criterion of time of appearance of oxygen bubbles in 3% hydrogen peroxide, three categories of nonfermenters were established. The rapid catalase producers included Achromobacter xylosoxidans and Achromobacter species; Acinetobacter anitratus and Acinetobacter lwoffii; Bordetella bronchiseptica; CDC group IVE; Pseudomonas aeruginosa, P. fluorescens, P. putida, P. diminuta, and P. acidovorans; and Moraxella urethralis and M-6. The delayed catalase producers included Bordetella parapertussis, CDC group VA-1, P. alcaligenes, P. cepacia, P. mendocina, P. pickettii (VA-2), P. pseudoalcaligenes, P. putrefaciens, P. stutzeri, P. testosteroni, and P. vesicularis. The third group consisted of an additional 17 taxa of nonfermenters which were classified as moderate catalase producers.


Adhesion to a human cell line by Escherichia coli strains isolated during urinary tract infections.

It has been shown that some, but not all, Escherichia coli strains isolated from urine adhere, in vitro, to the surface of uroepithelial or vaginal cells. In the present study, 212 strains, isolated from urine of 212 infected patients, were tested for adhesion by using an in vitro human cell line assay. A variable degree of attachment to the cell monolayer was detected in these strains. From patients with cystitis, only 19 (9.7%) of the 195 strains examined were adherent, whereas 5 (29.4%) of the 17 pyelonephritis strains had similar properties (P less than 0.05). To investigate the incidence of adhesion in the clinical manifestations of urinary tract infection, a sample of patients was picked at random from those with cystitis. During cystitis caused by adhesive bacteria, patients suffer more often from macroscopic hematuria than from dysuria, frequency, or recurrency (P less than 0.05). This study shows that E. coli strains isolated from urine samples possess a strikingly difference in capacity to adhere to a human cell line surface as demonstrated previously with uroepithelial or vaginal cells. Moreover, according to these data, the adhesion of E. coli may be considered as a virulent factor and would play a part in the infection of the urinary tract in humans.


Acceptability and cost savings of selective sputum microbiology in a community teaching hospital.

Our experience in introducing selective sputum microbiology into a clinical laboratory was recorded prospectively and analyzed. Based on low-power microscopy with determination of ratios of polymorphonuclear to squamous cells, 32% of specimens were discarded as unfit for culture. Speedy processing and prompt telephone calls afforded opportunities to replace these with better specimens, but only 29% of rejected specimens were resubmitted. Interpretive readings of smears for microorganisms yielded meaningful yielded meaningful information to clinicians and correctly predicted culture results in 73.8% of acceptable specimens. Technological time was similar to that required to process the same number of specimens in the usual way, but rejection of unsatisfactory specimens led to a 22% saving in supplies. Clinicians readily accepted the new system. Where nurses are responsible for specimen collection, they must be informed of the rationale for selective culture and the unreliability of gross visual inspection in evaluating sputum.


Rapid identification of Prototheca species by the API 20C system.

The conventional auxanographic method of testing for the assimilation of carbohydrates and alcohols by the various species of Prototheca requires at least 2 weeks of incubation at 25 to 30 degrees C before definitive results are obtained. Even though Prototheca spp., in culture as well as in fixed tissues, can be identified more rapidly by fluorescent-antibody techniques in which species-specific reagents are used, such diagnostic facilities and reagents are not available in most diagnostic laboratories. The API 20C clinical yeast identification system, a commercially available ready-to-use micromethod, was found to permit the definitive identification of P. stagnora, P. wickerhamii, and P. zopfii within 4 days.


Detection of antibodies to alphaviruses by enzyme-linked immunosorbent assay.

Cell culture-derived antigens detected antibodies to alphaviruses in human sera with the enzyme-linked immunosorbent assay technique. Results correlated with those from hemagglutination inhibition and neutralization tests.


Stability of anti-Candida precipitating antibody in stored sera as determined by counterimmunoelectrophoresis.

Prolonged storage of sera at -20 degrees C did not significantly affect anti-Candida precipitin titers measured by counterimmunoelectrophoresis when compared with the original determinations.


The effect of tetracycline and/or scaling on human periodontal disease.

The objective of this study was to test the efficacy of scaling and root planing with or without adjunctive tetracycline therapy in the treatment of periodonitis in humans. The presence of plaque, gingival inflammation, probing depths and attachment levels was assessed for all teeth in 12 patients with chronic, advanced periodontitis. After an initial examination all patients were given detailed oral hygiene instructions. The teeth in one-half of each arch were then scaled and root planed. The teeth in the contralateral half were not treated. Six patients were given tetracycline (1 gm/day) during the first and second weeks and the seventh and eighth weeks of the trial. The study thus included four different treatment groups: 1) no treatment, 2) scaling and root planing alone, 3) tetracycline administration alone, and 4) scaling and root planing combined with tetracycline administration. All patients were reexamined at 8 and 25 weeks subsequent to the initiation of therapy. Both PlI and GI scores decreased significantly in all groups. The GI scores were significantly lower in the scaled and root planed areas as compared to the contralateral sides at both the 8- and 25-week examinations. The PlI score was lower in the scaled and root planed areas only at the 25-week interval. The gingival probing depths were reduced in all groups. A significantly greater decrease in probing depth, however, was noted in scaled and root planed areas. There was a trend to gain of attachment in the treated areas but the magnitude of the gain was very small. The findings of the trail also revealed that the administration of tetracycline had only a minor effect on the parameters examined.


Periodontal self-examination. A motivational tool in periodontics.

The institution of proper oral hygiene procedures and habits is a learning process. This paper describes a self-instructing periodontal self-examination program to be used in the initial phase of periodontal treatment. The program was designed in an effort to facilitate learning by taking the teaching conditions into consideration. The program tries to utilize the patient's curiosity and need for activity and to involve the patient himself in an effort to make the patient apprehend the relevance of subject matter. The program also allows for an individualized learning speed of the patient. The self-examination program was tested on 108 periodontal patients (19-75 years of age) and the patients' findings were compared to those made by a dentist. Questionnaires before and after the self-examination were used in the evaluation of opinions of the patient. The present study showed that the patients were able to perform the self-examination without individual professional guidance. A rather close correlation was noted between findings made by the patient and the dentist. Furthermore, the program was well accepted and appreciated by the patients according to their answers on the questionnaires.


Conversion of a stable T-cell lesion to a progressive B-cell lesion in the pathogenesis of chronic inflammatory periodontal disease: an hypothesis.

Changes in the host's immunological response or, alternatively, changes in the oral microflora have been implicated as possible mechanisms by which a stable lesion of chronic inflammatory periodontal disease may become a progressive lesion leading to tissue destruction and tooth loss. It has recently been established that the progressive lesion in humans can be unequivocally considered as a B-cell response. Circumstantial evidence exists which suggests that the stable lesion is in fact a T-cell-mediated mechanism. An hypothesis is presented to explain the change from a stable to a progressive state in terms of a shift from a predominantly T-cell lesion to one involving large numbers of B-cells. Mechanisms of this shift in cell populations are considered together with a discussion of possible means of preventing such a shift.


Clinical evaluation of spiramycin and erythromycin in control of periodontal disease.

Two studies are reported. Each was double-blind in which Spiramycin was compared to Erythromycin and a placebo, to determine the value of Spiramycin as a therapeutic agent in the control of periodontal disease. In Study 1, 48 adults with varying degrees of periodontal disease were randomly assigned to treatment and control groups. Assessments of gingival index, plaque height, pocket depth, crevicular fluid volume and wet plaque weight were made. During this 4-week clinical trial, the patients maintained their usual oral hygiene. The medication was administered systemically for 5 days, starting at the conclusion of week 2. Spiramycin significantly reduced the scores for the five parameters recorded. When comparison were made, the greatest recorded effect with Spiramycin treatment was found in patients with advanced periodontal disease. The indication of this trend favouring Spiramycin led to an extension of this clinical trial involving only patients with advanced periodontal lesions. This second study comprised 54 adults. The same parameters were measured over the same time period as in Study 1. Spiramycin again was responsible for the greatest reduction in the recorded scores. For example, average pocket depth was decreased by approximately 30%, whereas Erythromycin produced a reduction of 15%. It would appear that Spiramycin is of definite benefit in the management of periodontal disease, especially in the more advanced cases.


Nickel feeding in nickel-sensitive patients with hand eczema.

Ten women with vesicular hand eczema and delayed hypersensitivity to nickel were given 0.5 mg nickel supplements to their diets. The double-blind controlled supplements were given on Monday and Tuesday of each week for at least 1 month. The nickel supplement was lower than that used in previous studies, and only one subject had reproducible flaring of her vesicular dermatitis. We conclude that dietary restriction of nickel is not warranted based on nickel supplement studies, but nickel's role in hand eczema could be clarified by depleting nickel from body stores with chelating agents.


Efficacy of mycophenolic acid for the treatment of psoriasis.

The efficacy of orally administered mycophenolic acid (MPA), an inhibitor of guanosine monophosphate (GMP) synthesis, for the treatment of psoriasis, was studied in a double-blind fashion. Of twenty-one patients completing the study period, ten of eleven patients treated with MPA had a greater than 25% decrease in severity score compared with only two of ten patients treated with placebo. The placebo group had a slight increase in severity score compared to almost 50% reduction in the average severity score of the MPA-treated group. After termination of the double-blind portion of the study, the placebo group was treated with MPA and showed a 60% decrease in severity score. Adverse effects encountered included anorexia, nausea, vomiting, and diarrhea. One patient had an uncomplicated episode of herpes zoster. Other than a mild decrease hemoglobin, no hematologic toxicity was noted.


Thallium as an industrial poison (review of literature).

The presented reports on cases of occupational thallium poisoning clearly demonstrate that the possibility of their occurrence in industrial plants is very real. The number of such intoxications is much higher than that of non-industrial poisonings, but this is predominantly due to the less pronounced clinical picture and to the fact that specific tests for thallium are not performed. As a result, these cases partly escape registration altogether and partly are wrongly diagnosed. Thallium and its compounds belong to the first class of poisons, their dangerousness being enhanced by their easy permeability through the skin. Industrial thallium poisoning can be either acute or chronic, but in all cases, it is characterized by a long duration and severity of its course. Strict hygienic demands on the organization of the technological process and the measures of protection of persons working with thallium are indispensable. Compulsory examination of the urine of those working with thallium for the presence of this substance should also be introduced.


Taxonomic position of Klebsiella atlantae and Klebsiella edwardsii.

The taxonomic position of two species of the genus Klebsiella (K. atlantae and K. edwardsii) is being introduced. 211 strains of different origin were studied: 80 strains of K. pneumoniae, 46 strains of K. oxytoca, 50 strains of K. atlantae and 35 strains of K. edwardsii. Sixty biochemical characteristics were determined 40 of these pertaining to carbohydrate metabolism. It was discussed whether both are to be considered species or biotypes of another Klebsiella species, however, by determining citrate as carbon source, by MR test and by tests on malonate, gluconate, methyl-xyloside, 1 (--) sorbose, inulin, amylose, methyl-d-mannoside, glycogen, melezitose, VP test, amygdalin, d-tartrate and gas from glucose, we arrived at the conclusion that both could be considered species of the genus. These conclusions were confirmed by the determination of biotypes of both (according to C. Richard). Later, we expect to study their participation in human infective processes and their sensitivity by antibiotic therapy.


Experimental study of vaccines against Salmonella typhimurium infection.

Serological and protective activities of vaccines from S. typhimurium and S. minnesota were studied. It has been demonstrated that active protection against infection in experimental salmonellosis in mice can only be obtained by immunization of the animals using vaccines from complete antigenic complexes isolated from S-strains. It has been found that expressed anti-infection immunity (unlike anti-endotoxic immunity) is induced to the same extent by either high-molecular components (2,000,000 daltons and more), showing great serological activity, or components with relatively low molecular weight (15,000--20,000 daltons) and minimum serological activity. Vaccines from Ra- and Re-strains of S. minnesota do not induce resistance to S. typhimurium infection in mice in either active protection tests or passive protection tests.


Immunoreactive alpha and beta subunits of follicle stimulating and luteinizing hormones in peripheral blood throughout the menstrual cycle and following stimulation with synthetic gonadotropin releasing hormone (GnRH).

The concentration of immunoreactive alpha and beta subunits of human LH (hLH) and human FSH (hFSH) were measured in unfractionated serum throughout normal menstrual cycles, and when GnRH was administered at about midcycle. The RIA subunit systems employed were sufficiently sensitive and specific to measure basal levels of free alpha-hLH, beta-hLH, and alpha-hFSH. The beta-hFSH system lacked sufficient sensitivity to measure beta-hFSH in unfractionated serum. In normal cycles, alpha-hLH, beta-hLH and alpha-hFSH were shown to circulate in the free form with highest concentrations occurring at the time of midcycle peak of LH and FSH. The concentration of subunits during the follicular phase were not significantly different from those observed during the luteal phase of the cycle. In response to GnRH administration during the periovulatory phase of the cycle, the increases in circulating free alpha-hLH, beta-hLH, and of alpha-hFSH subunits were directly related to the increases in LH and FSH. Other investigators have shown that increases in circulating levels of free subunits are due to secretion from the pituitary gland rather than from peripheral dissociation of intact hormone. Therefore, it can be assumed that the increase in immunoreactive alpha-hLH, beta-hLH, and of alpha-hFSH subunits observed in this study at midcycle represent release of free subunits in response to endogenous or exogenous GnRH administration.


Production of pyrogenic exotoxin by groups of streptococci: association with group A.

Several groups of streptococci were tested for production of pyrogenic exotoxins (SPE) with Ouchterlony immunodiffusion, a newly developed passive hemagglutination inhibition assay, and an assay for pyrogenicity and capacity to enhance lethal endotoxin shock. With use of these assays, 68 (91%) of 75 group A streptococcal strains were positive for one or more of SPE types A, B, and C; seven were negative for both the known SPE types and antigenically unrelated pyrogenic exotoxins. Group A strains producing both SPE B and C were the most common, and strains producing A alone or AB and AC together were the least common. All of 11 rheumatogenic group A streptococci elaborated SPE C either alone or together with one or both of SPE types A and B. The 10 nephritogenic strains tested were positive for SPE B; five were positive for B alone. In contrast to group A streptococci, non-group A strains (41 tested) did not produce the known SPE types, and 19 of 19 tested were negative for antigenically unrelated pyrogenic exotoxins. Group A strains from Holland, India, and Japan also elaborated SPE. Several group A streptococci used widely in laboratory experiments were tested for SPE types produced.


Heterogeneous pituitary secretion in familial hypogonadotropic hypogonadism.

Dynamic testing of the hypothalamic pituitary system in familial hypogonadotropic hypogonadism has suggested the possibility of a central nervous disorder associated with variable pituitary secretory secretion. In order to investigate this issue further 7 patients of two families were studied. Male patients exhibited two types of FSH responses to LHRH administration. Two patients had a small response, and the other exhibited a normal response. The LH response was absent or small in both male and female patients. One month therapy with daily injections of LHRH did not improve pituitary responsiveness to a second LHRH test. Estrogen treatment given to females during one month had no improvement effect on another LHRH test. Estradiol benzoate produced a surge in both LH and FSH in half of patients tested which is surprising in the presence of a previous clomiphene negative response. Two of four women had elevated prolactin levels which increased defectuously after metoclopramide administration which could suggest an abnormal hypothalamic status. On the basis of these results it seems that familial hypogonadotropism is originated by an abnormality at two levels, the anterior pituitary and the hypothalamus as well.


Human immunity to group B streptococci measured by indirect immunofluorescence: correlation with protection in chick embryos.

An indirect immunofluorescence (IF) assay has been developed as a useful semiquantitative method for determination of type-specific IgG antibody in human sera to the five serotypes of group B Streptococcus. Antibody titers measured by IF correlated with passive protection in chick embryos, and antibody titers associated with chick embryo protection were delineated. Except for types Ia and Ic, IF antibody to each of the streptococcal types was completely absorbed by homologous strains, and antibody titers were unchanged by incubation with heterologous bacteria. For types Ia and Ic, IF antibody was absorbed by either the Ia or the Ic strain and by native Ia carbohydrate antigen. Antibody titers measured by IF and chick embryo protection against types Ia and Ic were similar, but were divergent for Ib and Ic, a finding suggesting that antibody is predominantly directed to the major carbohydrate determinants. In addition, 29 of 31 sera that had been tested in chick embryos yielded comparable results in mice against challenge with type Ia group B Streptococcus, a finding further validating the chick embryo assay. Sera from all of 43 mothers of infants infected with group B streptococci had antibody titers by IF that were less than titers associated with protection in chick embryos.


Prevalence of antibodies to Toxoplasma gondii in pregnant women in Oregon.

Sera from 95,929 pregnant women were screened for antibodies to Toxoplasma gondii with the indirect hemagglutination test (IHA) at a 1:64 dilution of the sera. An indirect fluorescent antibody-IgM specific test (IFA-IgM) was used on all sera found to have an IHA titer of greater than or equal to 1:256. From August 1973 to December 1976, 8.1% of pregnant women had IHA titers of greater than or equal to 1:64. In addition, 129 (18.4%) of 700 pregnant women with IHA titers of greater than or equal to 1:256 had IFA-IgM titers of greater than or equal to 1:4. The IHA test was an acceptable test for mass screening of sera from pregnant women. In Oregon, one in every 200 women contracts toxoplasmosis during her pregnancy.


Prevalence of antibody to Legionella pneumophila in middle-aged and elderly Americans.

An indirect fluorescent antibody (IFA) test was used to establish the background prevalence of antibody to Legionella pneumophila in single serum specimens from 1,143 persons. The serum specimens had been obtained from volunteers 46 years of age and older who were not acutely ill and who resided in the areas of Atlanta, Georgia; Washington, D.C.; Houston, Texas; and Rochester, New York. The overall prevalence of seropositivity (reciprocal titer, greater than or equal to 64) was 1.7%. The prevalence of seropositivity did not vary with age, sex, or geographic location. Groups of persons in which the prevalence of reciprocal titers of greater than or equal to 64 is significantly higher than 1.7% may have unusually great exposure to L. pneumophila. In the population tested, a reciprocal IFA titer of greater than or equal to 64 would have a specificity of 98.3% in the diagnosis of an acute illness as Legonnnaires' disease.


Subtraction serum bactericidal assay: a method for estimating in vivo effects of antibiotic combinations.

The subtraction serum bactericidal assay has been developed to assess the effects of the individual components of antibiotic combinations in serum specimens from patients with serious bacterial infection. The technique can be performed easily with conventional microtiter technology, and the results compare favorably with those obtained by conventional in vitro determinations of the additive and synergistic activity of fixed antibiotic combinations against various Enterobacteriaceae. Three combinations of gentamicin and ampicillin were used, and synergistic or additive activity was demonstrated against each of the 11 clinical isolates tested, but only with one or two of the antibiotic combinations. This finding suggests the clinical importance of a test that can determine the effects of the actual concentrations of individual antibiotics that are achieved in patients with serious infections that are being treated with antibiotic combinations.


[An experimental study on the regeneration of the peripheral nerve--adaptation of the funiculus at the sutured site (author's transl)].

We consider it necessary to investigate the passage of axon through the sutured site, besides problems of misdirection, in order to understand the factors which affect the regeneration of the peripheral nerve. We performed the following experiments assuming that different situations occurring at sutured site is to be considered as mono-funiculus situation, and studied them mainly from the histological point of view. Twenty-five adult hybrid dogs were used. We performed several different experiments, mentioned below, on the sciatic nerve, at about 3 cm below the greater trochanter with 9-0 monofilament nylon by microsurgical technique. The sciatic nerve was separated 4 cm away from the surrounding tissue, and only the peroneal nerve funiculus was isolated 2 cm away from the other funiculus and was cut at the center. Models of experiment. 1. Proper suture of both cut end...Optimum. 2. Suture by tension after excision of 1 cm in length...Tension, 3. Suture by compression...Compression, 4. Suture by shifting both cut ends about 1/2 of their surface...Offset, 5. Suture by buckling...Buckling, 6. Suture with gap of 5 mm after excision of 5 mm in length...Gap. Five weeks and ten weeks after the operation, the nerves were examined electrophysiologically and histologically. The nerve was stimulated at about 1 cm proximal to the sutured site directly using needle electrode, and the most distal part was searched for, where the nerve action potential was recorded. For the histological study, the nerve was sectioned longitudinally and transversely. These specimens were stained by H. E., Holmes' (for the axon), and L. F. B. method (for the myelin sheath). The regeneration of the nerve was classified into four grades, according to the number and the size of the axon passing through the sutured site, namely poor, fair, good, excellent. 1) The offset of the funiculus at the sutured site is the most important factor which disturbs the regeneration of the axon. 2) The influence of about 5 mm gap is not so big for the regeneration of the axon, compared to the severe offset. 3) The moderate tension which can be produced by the ordinary microsurgical suture does not much influence the regeneration of the axon, and the compression at the sutured site has not much influence to the nerve regeneration as long as the adaptation is good.


[Experimental study on an artificial hip joint made of Al2O3 ceramics (author's transl)].

For the purpose of developing the ceramic artificial hip joint, we carried out biological and mechanical experiments. Tiny blocks of polycrystalline ceramic were inserted into the femurs of rabbits. Also, ceramic powder was injected into the knee joints of rabbits. Biological reaction were examined after varying intervals. It was proved, as a result, that ceramics have good affinity with living tissue. As a next step, wedge-shaped test pieces were inserted into the distal end of the femurs of dogs and tensile tests were carried out to investigate the degree of fixation of ceramic with bone. The result was that ceramic test pieces showed firmer fixation than those of metal. In the hip joints of five dogs, ceramic total hip prostheses for dogs were implanted. The dogs were autopsied after varying intervals and investigated histopathologically and scanning electron microscopically. Fixation of the socket and the prosthesis with the bone was superior to those made of metal and, moreover, virtually no wearing had taken place. However, the socket or prosthetic stems in four dogs were observed damaged in some parts. From the above mentioned, it is evident that when making ceramic total hip prostheses, we have to select ceramics of good quality and thicken their weightconcentrated parts by a device of its own design or use partly metal components coated with ceramic.


Butorphanol/acetaminophen double-blind study in postoperative pain.

An oral butorphanol/acetaminophen (4 mg/650 mg) combination product was evaluated for analgesic activity in 120 postoperative patients employing a double-blind experimental design. The combination product was significantly (p less than 0.05) superior to either butorphanol (4 mg) or acetaminophen (650 mg) as well as placebo. Except for acetaminophen which was only significantly different (p less than 0.05) from placebo at 2 hours according to pain relief, all other treatments were superior to placebo over the entire 4 hour observation period. The data demonstrate that butorphanol and acetaminophen have at least additive analgesic activity with a suggestion of synergism. A single tablet dose of the combination product (butorphanol 2 mg/acetaminophen 325 mg) was evaluated in a second study involving 60 patients and was significantly (p less than 0.05) superior to placebo. Both studies demonstrate that the butorphanol/acetaminophen combination product has potent analgesic activity with a minimal side effect profile.


Pentoxifylline -- a biomedical profile.

The therapeutical benefit of pentoxifylline (Trental) in vascular disorders and chronic diseases which provoke disturbances in nutritive microcirculation is reviewed. With its hemorheological activity, pentoxifylline offers a new approach to ameliorate impaired blood flow in affected microvasculature. This statement is given evidence by numerous experimental and clinical data which demonstrate efficacy in various indications, wuch as cerebrovascular insufficiency, senile organic brain syndrome, transient ischemic attacks, cerebral infarctus, ocular and otological circulatory disorders, peripheral angiopathies of arteriosclerotic, diabetic, or inflammatory origin with intermittent claudication, leg ulcers and other disturbances. In vitro and in vivo findings disclose that the efficacy is based on hemorheological effects, such as improving local hyperviscosity, hyperaggregability of red cells or platelets, erythrocyte fluidity and hypercoagulability resulting in a better oxygenation of affected tissues.


Cerebrovascular circulatory disorders: new aspects of pathophysiology and therapy.

After reviewing new aspects in the pathophysiology of the poststenotic cerebral ischemia as the cause of the various syndromes of cerebrovascular disorders, therapeutic approaches are discussed. The fatal vicious cycle of the disturbances of the nutritive blood flow within the cerebral microcirculation can be interrupted by means of pentoxifylline. By amelioration of the disturbed flow properties of blood in the microcirculation due to improvement of red cell deformability and inhibition of platelet aggregation, oxygen supply is enhanced and more glucose offered. Membrane permeability and functions of the cells are normalized by the inhibitory action on edematous changes in the brain tissue and by removal of the mechanical obstacles of microcirculation. The disturbed cerebral metabolism is stimulated by enhancement of the energy-rich phosphates in the brain cells. The combined rheological, antiedematous and metabolic effects of pentoxifylline offer a complex therapy of cerebrovascular insufficiency.


Immunofluorescence studies on deoxyribonuclease from mouse teratocarcinoma cells during cell differentiation.

Specific anti-DNase-I IgG have been used to detect deoxyribonuclease in teratocarcinoma cells by an indirect immunofluorescence method. All the cells studied show fluorescence staining. However, the patterns are quite different in embryonal carcinoma cells (amorphous cytoplasmic fluorescence and absence of nuclear staining) as compared to differentiated cell lines (diffuse, bright granular nuclear and fibrillar cytoplasmic fluorescence). It is possible by this method to distinguish different cell types derived from the same origin. Deoxyribonuclease from teratocarcinoma cells can therefore be considered as a marker of cell differentiation in this system.


Mercury-induced loss of K+ from yeast cells investigated by electron probe x-ray microanalysis.

According to Passow & Rothstein (1960), the mercury-induced loss of K+ from yeast cells is an all-or-none effect. This hypothesis was tested by analysing individual yeast cells by means of energy-dispersive X-ray microanalysis. A dual effect of mercury was observed. The cell population was split into two parts: one part consisted of cells that had suffered a (nearly) complete loss of K+- the number of these cells increased with increasing concentrations of HgCl2; the other consisted of cells that had only lost part of their K+ content--these cells showed a normal distribution around a central value that decreased with increasing concentrations of HgCl2. Our analysis shows that the effect of mercury is more complex than originally suggested and that, in addition to an all-or-none effect, a gradual loss of K+ occurs.


Thermophilic and thermotolerant fungi in poultry droppings in Nigeria.

Ten species of fungi were obtained from poultry droppings in Nigeria. Six of these are true thermophiles while the other four are thermotolerant. Aspergillus fumigatus Fresenius, Mucor pusillus Lindt and Thermoascus aurantiacus Stolk are known human pathogens. Except for M. pusillus, all the thermotolerant species had a higher occurrence at 45 degrees C while the thermophilic varieties were readily obtained at 50 degrees C.


Generation time statistics of Escherichia coli B measured by synchronous culture techniques.

Synchronous cultures of Escherichia coli B were produced under various environmental conditions. Analysis of the cell number data permitted the characterization of the generation time distribution for these organisms and the estimation of the mother-daughter generation time correlation coefficients. For all growth conditions, the distribution of generation times was found to be symmetrical with a coefficienoefficient was significantly negative at doubling times between 40 and 64 min. However, the results for a culture growing in succinate medium at 37 degrees C, which had a significantly greater generation time, yielded a correlation coefficient close to zero. Within the range of temperatures studied (26 to 37 degrees C), no significant effect on the correlation coefficient was observed.


Mutational consequences of exposure to ethylene oxide.

Additional restrictions on exposure to ethylene oxide, an effective and widely-used sterilant, have recently been proposed (EPA, 1978). Substantial amounts of evidence indicate that ethylene oxide is mutagenic. The data from sub-mammalian systems, including demonstrations of point and chromosomal mutations in bacterial and eukaryotic systems, and from a limited number of studies in mammalian systems are reviewed. The accumulated information, and its context of current guidelines for mutagen testing, are considered in terms of extrapolation to evaluation of potential risk to exposed humans. The available evidence does not appear sufficient to condemn ethylene oxide as a human mutagen at currently acceptable exposure levels.


Interrelation of DNA replication, specific growth rate and growth temperature in the sensitivity of Escherichia coli to cold shock.

Escherichia coli W3110 was grown in a chemostat under conditions of carbon limitation at various temperatures and specific growth rates (mu). Exponential survivor-time curves following cold osmotic shock were biphasic. These could be described by the sum of two exponential functions representing the survival of sensitive and resistant fractions of the population where the size of the sensitive fraction was directly proportional to mu. Decimal reduction times for the more resistant fraction were unaffected by mu yet decreased with increasing growth temperature. Sensitivity to cold shock was evaluated for an E. coli CR34 mutant, temperature-sensitive in initiation of DNA replication. When grown in the chemostat at the non-restrictive temperature (30 degrees C) sensitivity was directly proportional to mu. Following a rise in the incubation temperature to 42 degrees C, sensitivity decreased markedly and reached a minimum 45 to 60 min after the temperature increase. Sensitivity of the E. coli mutant grown at 30 degrees C and raised to 42 degrees C for 1 h was low and relatively unaffected by growth rate.


Anaerobic growth of Escherichia coli K12 with fumarate as terminal electron acceptor. Genetic studies with menaquinone and fluoroacetate-resistant mutants.

Fifteen independent menaquinone biosynthesis mutants (men) of Escherichia coli K12, selected for their inability to use fumarate as terminal electron acceptor, were investigated. Two nutritionally distinct groups were detected. The major group (13 mutants) responded to 1,4-dihydroxy-2-naphthoate (DHN), 2-succinylbenzoate (SB) and its dilactone, whereas the minor group (2 mutants) only responded to DHN. DHN was at least five times more effective than SB  but it inhibited growth at concentrations greater than 10 microM. For anaerobic growth on glucose minimal medium the auxotrophs responded to much lower concentrations of DHN and SB and these intermediates could be replaced by uracil. Anaerobic growth tests showed that glycerol, formate and H2 are good substrates for E. coli when fumarate is the ultimate electron acceptor but growth with lactate or with fumarate alone is poor. All 15 men mutations were located between glpT and purF at approximately 49 min in the E. coli linkage map. Cotransduction frequencies with relevant markers were: nalA (21%), glpT (35%) and purF (15%). The presence of at least three genetically distinct classes (menC and menD, SB-requirers; menB, DHN-requirers) was indicated using abortive transduction as a complementation test and three-factor genetic analysis. The relative orientation nalA...menC-(D,B)...purF was indicated. Fluoroacetate-resistant mutants were isolated and four different classes were identified: ack, lacking acetate kinase; pta, lacking phosphotransacetylase; facA, lacking both of these activities; and facB, which retained both of these enzyme activities. Some of the pta mutants and all of the facA mutants failed to grow on media containing fumarate as terminal electron acceptor or anaerobically on glucose minimal medium. All four types had genetic lesions clustered between the men and purF sites. Average cotransduction frequencies with relevant markers were: nalA (4%), men (27 to 35%) and purF (71 to 80%).


Effect of R plasmid RPI on the nutritional requirements of Escherichia coli in batch culture.

The minimal nutritional requirements of Escherichia coli have been quantitatively determined in batch culture for cells with (R+) and without (R-) the R plasmid RP1. In these conditions R+ cells have a greater requirement than R- for several nutrients, particularly Mg2+, K+, Fe2+ and PO43-. The maximum growth rate in a simple salts medium was the same for R+ and R- cells. At low concentrations of phosphate, the specific growth rate of R+ cells differed from that found for R- cells. The R plasmid was stable in simple salts medium, irrespective of the nutrient ultimately depleted by growth, but, on storage, R+ cells survived for a shorter time than R- cells.


Allele specific and locus non-specific suppressors in Aspergillus nidulans.

Using N-methyl-N'-nitro-N-nitrosoguanidine, ultraviolet irradiation, ethyl methanesulphonate or 4-nitroquinoline-1-oxide mutagenesis and an enrichment method for the isolation of auxotrophs, 25 mutants with defects in the adA locus were obtained after screening 41,376 colonies. One of these, adA24, did not complement with any of the other adA mutants, had a very high reversion rate and had some other properties which usually characterize strains carrying nonsense mutations. All revertants of adA24 carried dominant suppressor mutations. A group of adA24 suppressors was tested for allele and locus specificity. They were found to suppress only some adA alleles, and at the same time, some mutations in the methG, methH, argB and proA loci. It is proposed that the allele specific and locus non-specific adenine suppressors are suppressors of nonsense mutations.


Cysteine auxotrophs of Salmonella typhimurium which grow without cysteine in a hydrogen/carbon dioxide atmosphere.

Cysteine auxotrophs of Salmonella typhimurium mutated in cysB, cysI or cysJ grew with sulphate as a sulphur source when incubated under a hydrogen/carbon dioxide atmosphere. Yields obtained under these conditions were equivalent to those characteristic of wild-type S. typhimurium. The same mutants failed to grow with sulphate as a sulphur source when incubated aerobically. Auxotrophs mutated in cysA, cysC, cysD, cysE, cysG and cysH required cysteine for growth under both incubation conditions. The results suggest that mutations in cysB (regulation of the several cys operons) and also cysI and cysJ (sulphite reductase activity) can be circumvented during anaerobic growth under hydrogen.


Is the DNA of virus T7 methylated?

DNA modification of T7 wild type and of T7 M-mutants was studied by determining the percentage of 5-methylcytosine (5MC)/cytosine (C) and N6-aminopurine (6MA)/adenine (A) and by evaluating the plating efficiencies of restriction-sensitive T7 M-mutants on modifying and non-modifying host strains. Only 0.03% adenine and 0.02% cytosine were methylated in the DNA of T7 wild type as well as in T7 M-mutants, which was independent of the host DNA methylation (30- to 50-fold higher). The restriction of T7 M-mutants, determined from the plating efficiencies, was not altered on modifying or non-modifying hosts. These results indicate that host-specific modification is blocked during T7 development and that this is not due to the M-protein.


Comparison of tricalcium phosphate and frozen allogenic bone implants in man.

As part of their treatment, eight patients with 47 infrabony pockets and horizontal bone defects had 29 tricalcium phosphate and 18 frozen allogenic bone implants placed. One year after surgery the sites were reentered. At the tricalcium phosphate implant sites the average amount of bone apposition was 1.2 mm and pocket depth induction 1.8 mm; 38% of the pockets remained deeper than 3.0 mm. At the allogenic bone sites the average amount of bone apposition was 1.5 mm and pocket depth reduction was 2.0 mm; 22% of the pockets remained deeper than 3.0 mm. The implant materials were well tolerated and there were no complications during the period of the study. Though storage and handling of tricalcium phosphate was simpler, use of allogenic bone led to greater bone apposition and reduction in pocket depth.


A cementum-bound antigen: its reaction with serum antibody and localization, in situ.

The results which have been presented give clear evidence to the presence of an antigen(s) on the cementum of teeth exposed to a periodontal pocket, which is capable of reacting with human serum antibody. It was not possible to demonstrate human antibody reactivity against any components derived from the cementum of completely unexposed bony impacted teeth. Regardless of any speculations dealing with the character or origin of such antigens, their very presence would suggest they may have profound implications in the etiology and progression of the periodontal disease process.


[Methods available for measuring temperature (author's transl)].

Numerous techniques are in use in medicine for temperature determination either from thermal conduction phenomena, or from hot body radiations. These are essentially thermometry, radiometry and thermography. During attempts to treat cancer by hyperthermia, temperature knowledge, at the level of the target volume and the adjoining parts, is essential. These deep temperature measurements are yet a problem and certainly need new sensor technologies.


Balint, the doctor, and the fear of being unscientific.

The current debate on the contribution of Michael Balint's work to general practice has been initiated by Sowerby's (1977) lengthy critique.Sowerby's arguments, however, depend on one particular definition of science, simplify some complex issues, and have rigid and restrictive qualities. I give some examples to illustrate this.Secondly, Sowerby's definition of the science of psychology leads to an intellectual separatism which Balint sought to reduce. The alternative diagnosis of ;depressive illness' is neither more helpful nor precise.Finally, criticisms of Balint seminars which Sowerby perceives as dangerous are challenged. I argue that Balint's approach in verifying and refuting hypotheses in the face of prospective observations and evidence was truly scientific.


The leukocyte adherence inhibition assay in rheumatoid arthritis.

Peripheral blood leukocytes (PBL) from patients with rheumatoid arthritis (RA) and from control subjects were exposed to rheumatoid and osteoarthritic synovial membrane extracts. The number of nonadherent PBL in the presence of each extract was monitored in a test tube leukocyte adherence inhibition (LAI) assay. Six of 7 rheumatoid synovial extracts produced significantly greater nonadherence values when RA leukocytes were used as the test cell (36 +/- 5) compared with values obtained when control leukocytes were used (-5 +/- 3). Preincubation of LAI reactive leukocytes from RA patients with the RA synovial extracts abrogated the positive response, whereas preincubation with the OA extract had no effect. These studies indicate that leukocytes from RA subjects respond to a greater degree to extracts derived from rheumatoid synovium than to extracts derived from osteoarthritic synovium and add further support to the concept that unique substances (putative neoantigens?) are present in RA synovium.


Mutagenicity of halogenated and oxygenated three-carbon compounds.

Four structurally related three-carbon compounds, known for their antifertility activity in the male, and the brominated derivatives of two of these compounds were tested for mutagenic activity by the Salmonella typhimurium test of Ames et al. In the presence of strain TA-100, a base-pair substituion detector strain, 1,2-dibromo-3-chloropropane (DBCP), was the most active compound tested but required enzymatic conversion by 59 microsomal preparation to an active mutagen. Three of these compounds containing an epoxide group-epichlorohydrin, epibromohydrin, and glycidol-were highly active direct mutagens, not requiring 59 for activation, alpha-Chlorohydrin was the least active compound tested; alpha-bromohydrin was 40 times more active than its chlorinated analog. Epibromohydrin was only slightly more active than epichlorohydrin, but both were highly active. With both of the halogenated epoxides, 59 preparation caused a substantial decrease in mutagenic activity at every concentration tested. All six compounds showed dose-related responsiveness for the base-pair substitution detector strains used. However, they were relatively inactive against the frameshift detector strain of S. typhimurium, TA-98. Glycerol, propylene glycol, and n-propanol, which are also three-carbon compounds containing one or more hydroxy groups, were inactive when trested at high concentrations with strain TA-100.


Lymphomatoid granulomatosis of the larynx in a renal transplant recipient.

This is a case of lymphomatoid granulomatosis in a renal transplant patient, which presented as an ulcerating pharyngeal lesion and caused death by exsanguination from carotid artery erosion. The diagnosis was established at limited necropsy on the basis of a characteristic vaso-infiltrative and atypical lymphoreticular infiltration as defined by Liebow, et al, in 1972. As far as can be ascertained, this is the second reported case of lymphomatoid granulomatosis in an immunosuppressed patient and also is a presumed localized extrapulmonary form of this disorder which has recently been reported. The striking histologic similarities to midline malignant reticulosis are discussed.


Serum immunoglobulin concentrations, malarial and schistosomal antibodies in patients with massive splenomegaly in Malawi.

Serum immunoglobulin concentrations, malarial antibodies and schistosomal antibodies were measured in 33 patients with a provisional diagnosis of schistosomal splenomegaly, 16 with TSS of presumed malarial aetiology and in 52 controls. IgG and IgM were higher in both splenomegaly groups than in the controls and IgG was significantly higher in patients with schistosomal splenomegaly than in TSS. Although a very high IgM was found more often in the TSS group, there was no significant difference between the mean IgM levels in the two splenomegaly groups. The mean antischistosomal antibody titres were significantly higher in the schistosomal group than in those with TSS but there was no difference in the antimalarial antibody titres. These results emphasise the problems of diagnosis of gross splenomegaly in areas where schistosomiasis and malaria coexist.


[Laboratory and clinical studies on cefuroxime (author's transl)].

The authors have carried out the laboratory and clinical studies of cefuroxime (CXM). The results were as follows: The sensitivity was measured by plate dilution method on 26 strains of S. aureus, 22 strains of E. coli and 24 strains of K. pneumoniae isolated from patients. The distribution of sensitivity of S. aureus was 0.78 approximately 3.13 micrograms/ml and the peak of distribution was 1.56 micrograms/ml. The distribution of sensitivity of E. coli was 1.56 approximately 50 micrograms/ml and the peak was 6.25 micrograms/ml. The growth of 79.2% K. pneumoniae was inhibited in concentration of less than 3.13 micrograms/ml. CXM was given intravenously for 30 minutes at a single dose of 20 mg/kg to 3 children. The serum mean levels of CXM were 99.0 +/- 10.6 micrograms/ml at 30 minutes, 18.0 +/- 10.7 micrograms/ml at 1 hour, 7.0 +/- 2.0, 2.2 +/- 0.6, 0.79 +/- 0.2 microgram/ml at 2, 4 and 6 hours after drip infusion for 30 minutes, respectively. Mean half life was 48 minutes. The mean urinary recovery rate was 96.2% up to 8 hours after administration. CXM was effective in 9 of 10 cases of bacterial infections. No side effect was observed except for 1 case with elevation of serum transaminase.


Deletion of mitochondrial genetic markers in yeast by ethidium and the photoaffinity probe, ethidium azide.

Induction of petite (cytoplasmic-respiration-deficient, rho-,rho-) mutations in yeast and deletion of mitochondrial drug-resistance genetic markers were compared after after treatment with ethidium and the corresponding photoaffinity probe, ethidium azide. Deletion of mitochondrial drug-resistance markers for chloramphenicol, erythromycin and oligomycin in these petite mutants was observed during prolonged treatment times with ethidium and with ethidium azide in the dark. A similar loss of drug-resistance markers was also observed in petites produced by photolytic treatment with the azide analogue, although the rate of loss appeared to be somewhat less. These results confirmed the usefulness of photoaffinity labeling with ethidium monoazide for studies of mitochondrial mutations.


Quartan malarial nephrotic syndrome in children.

Quartan malarial infection causes an immune complex nephritis in some individuals, which, once established, is sustained by mechanisms not yet fully explained, but which probably involve autoimmune processes. The presenting clinical and biochemical findings of the quartan malarial nephrotic syndrome are similar to those classically described for the nephrotic syndrome in childhood, but the renal pathology seen on light, electron, and immunofluorescent microscopy show striking differences and distinctive features. The disease tends to pursue a chronic course and in most patients is nonresponsive to treatment with antimalarial drugs, prednisolone, and immunosuppresive drugs. The overall prognosis is poor, with most patients developing hypertension and evidence of renal failure within 3 to 5 years of onset.


Pathophysiology of Tamm-Horsfall protein.

Tamm-Horsfall protein, a renal glycoprotein present in normal urine, is the primary constituent of urinary casts. Immunoelectron microscopy has shown that this protein is localized selectively along surface membranes of the thick ascending loop of Henle. In this surface membrane site, the unique aggregation and gel formation of Tamm-Horsfall protein in response to increasing concentrations of electrolytes within physiologic ranges may influence the permeability characteristics of this nephron segment. These aggregation characteristics also play a role in pathologic conditions and lead to the prolonged persistence of interstitial Tamm-Horsfall protein deposits in several tubulointerstitial diseases. Recent studies have demonstrated immunologic responses to this protein, including an immune complex tubulointerstitial nephritis in rats mediated by autoantibodies to Tamm-Horsfall protein.


[Keratoplasty and reconstruction of the anterior segment of the eye after severe ocular trauma (author's transl)].

Severe ocular trauma is frequently not limited to the cornea, but affects the entire anterior segment of the eye. This requires "reconstruction" of the anterior segment. The procedure is long and complicated, but it is definitely justified to attempt to restore and save some vision, espeically in one-eyed patients or when both eyes have been affected by the accident.


[On the technic of dacryocystorhinostomy (author's transl)].

A new simplified operative technique for dacryocystorhinostomy is presented. The modifications are compared with the methods of Toti, Ohm, Dupuy-Dutemps, Kaleff and Hollwich.


Developmental patterns of alcohol dehydrogenase and aldehyde dehydrogenases in homogenates and subcellular fractions of rat liver.

Both alcohol dehydrogenase (ADH) and the two isoenzymes of aldehyde dehydrogenase (ALDH-I-NAD+ and ALDH-II-NAD+) were first detected in foetal rat liver about 5 days before birth. All enzymes developed gradually and showed no abrupt increases in activity. The specific activities of ALDH-I-NAD+ and ALDH-II-NAD+ in the mitochondrial fractions, ALDH-II-NAD+ in the microsomal fractions and ADH in liver homogenates all produced a major percentage of the adult activity within a month, whereas the total activities increased over a longer part of the developmental period.


The effects of the hypocholesteremic compound 3 beta-(beta-dimethylaminoethoxy)-androst-5-en-17-one on the sterol and steryl ester composition of Saccharomyces cerevisiae.

When yeast was grown in the presence of 10(-4) M 3 beta-(beta-dimethylaminoethoxy)-androst-5-en-17-one (DMAE-DHA), the compound 2,3;22,23-dioxidosqualene (DOS) accumulated. Total free sterol was reduced by about 30%, whereas almost no steryl esters were found. The same drug at lower concentration (3 x 10(-6) M) caused a slight increase in steryl ester production, and a 24% reduction in free sterol content. The marked accumulation of ergostra-5,7,22,24(28)-tetraen-3 beta-ol with 3 x 10(-6) M DMAE-DHA indicated that the C24-28 reductase is especially sensitive to the action of the drug.


[Epidemiological study of onchocerciasis and malaria in Bamendjin dam area (Cameroon). Malacologic fauna and risks of schistosomian introduction (author's transl)].

Report of survey in Bamendjin dam area indicates that 25 p. 100 of the population have a blood smear positive for malaria (P. falciparum) and 80 p. 100 have a positive indirect immunofluorescent test for malaria. The vector is A. funestus. In male inhabitants 23,2 p. 100 of the snip-biopsies are positive for O. volvulus and 40 p. 100 of the indirect immunofluorescent test are positive. In female inhabitants the respective ratios are 14,4 p. 100 and 48,8 p. 100. There is no urinary or intestinal schistosomiasis in this area but specimens of potential vectors have been detected.


[Evaluation of two methods for detecting HBS antigen in serum (author's transl)].

Two methods of third generation are described: the inverse passive agglutination test and the immunoenzymologic method of the ELISA test. From 500 serum tests, it is suggested that ELISA test has a sensibility of 5,2 p. 100 superior to that of the inverse passive agglutination test which, in addition gives 1 p. 100 of false positive results. It must be noted that the ELISA test requires a very careful technical skill.


[Immunoenzymatic diagnosis (ELISA) of human African trypanosomiasis. (A comparative study of several antigens) (author's transl)].

A comparative study, by ELISA, of purified exoantigen and of five crude antigenic extracts from several strains of T.b. gambiense and T.b. brucei has shown a wide range of results. The best sensitivity is obtained with virulent strains from human origin. For more accuracy, an association of such antigens would be preferable.


Nucleotide sequence of the region required for maintenance of colicin E1 plasmid.

Plasmids carrying various portions of colicin E1 plasmid (ColE1) DNA have been isolated in an attempt to determine the regions of ColE1 DNA which are required for maintenance of the plasmid in bacteria. To construct the plasmids, the DNA of a ColE1 derivative that contains a gene which controls ampicillin resistance was cleaved by the restriction endonuclease HaeII. The digestion products were joined by T4 DNA ligase and then used to transform bacteria to ampicillin resistance. The plasmid derivatives obtained in this way were always composed of certain HaeII segments. These contain approximately 10% of the ColE1 genome and include the origin of replication of ColE1. We presume that the region of ColE1 which is common to all these derivatives is required for maintenance of the plasmid. After a description of these results, the nucleotide sequence of this region is presented, and possible roles of the region in plasmid replication and maintenance are discussed.


The DNA-protein relaxation complex of the plasmid RK2: location of the site-specific nick in the region of the proposed origin of transfer.

The broad jost range plasmid, RK2, has been isolated as a DNA-protein relaxation complex. Nicking of the plasmid DNA in the relaxation complex occurs at a single specific site (rlx) located approximately 20 kb away from the origin of DNA replication. A cis-acting function required for plasmid transfer, the presumptive origin of transfer, maps in the same region as rlx. The region of RK2 encompassing rlx has been cloned onto pBR322 and shown to promote mobilization of the hybrid plasmid by an RK2 derivative. These results indicate that the RK2 relaxation complex nicks at or near the origin of transfer of the RK2 plasmid.


Some properties of the chloramphenicol resistance transposon Tn9.

We have isolated variants of the plasmid RTF which have received the transposon Tn9 from bacteriophage P1Cm. We have shown by the formation of heteroduplex molecules between one RTF:Tn9 derivative and R100.1 that Tn9 is homologous to the r-determinant region of R100.1 which carries the determinants for chloramphenicol resistance. This suggests that Tn9 was derived from an r-det like structure by deletion, possibly mediated by one of the flanking IS1 elements. In spite of the similarity in structure between Tn9 and r-det however, we have demonstrated two distinct differences in the behavior of these two elements: 1) Tn9 but not r-det, is able to amplify, by a recA dependent mechanism, when cells harboring RTF::Tn9 are grown in the presence of chloramphenicol, and 2) Tn9, unlike r-det, does not form extrachromosomal circular molecules when RTF::Tn9 is tegrated into the bacterial chromosome.


IS2-61 and IS2-611 arise by illegitimate recombination from IS2-6.

A more stable derivative of IS2-6 has been isolated, which had lost 54 bp of the 108 bp long insert characteristic of IS2-6. This new allele of IS2, IS2-61, segregates the remaining 54 bp to yield allele IS2-611. DNA sequence analysis shows that the segregation products of IS2-6 arise by recA-independent, illegitimate recombination at 9 bp long direct sequence repetitions.


DNA repair in Proteus mirabilis. VI. Plasmid (R46-) mediated recovery and UV mutagenesis.

The expression of plasmid R46-mediated recovery and mutagenic function (s) was studied in P. mirabilis, which is normally either weakly or non-mutable after UV exposure. The plasmid was found to confer on P. mirabilis enhanced UV resistance as well as UV-induced mutability for various types of forward mutations and reversion of the thr273 mutation. The plasmid enhanced survival of UV-irradiated phages in P. mirabilis both in unirradiated host cells and with increased efficiency after UV-exposure of host cells, as is characteristic of UV-inducible phage reactivation. Spontaneous mutability of P. mirabilis harboring R46 was about 2 to 7 times higher than that of cells without plasmid, depending on the marker, repair type, and plating density of the cells used. All of these R46-mediated rescue and mutagenic functions require the rec672 + gene function. It is assumed that the plasmid R46 adds functions to P. mirabilis comparable to those deficient in umuC and uvm mutants of E. coli (Kato and Shinoura, 1977; Steinborn, 1978) and that P. mirabilis possesses functions homologous to those controlled in E. coli by the recA + and lexA + genes. The significance of plasmid-mediated rescue and mutagenic functions for bacteria which lack the misrepair branch of mutagenesis, is discussed.


Lipid composition and polyene antibiotic sensitivity in isolates of Candida albicans.

When Candida albicans cells were grown on hydroquinone (Hy cells) or ascorbic acid (As cells) supplemented media, they exhibited a 26% rise and 16% drop in ergosterol content, respectively. C. albicans cells manifested a gradual increase in total lipid levels, when they were grown on n-alkanes of different chain lengths. The magnitude of the nystatin effect (in terms of proline uptake and K+ efflux) was more pronounced in cells having more ergosterol (Hy cells) compared with the cells having low levels of ergosterol (As cells), suggesting a correlation between nystatin sensitivity and ergosterol content of the C. albicans cells. However, such correlation could not be demonstrated in alkane grown cells where levels of different lipids were variable. Results demonstrated that several other lipids besides sterol may also influence the polyene antibiotic sensitivity in C. albicans cells.


Environmental factors influencing nitrate respiration in Escherichia coli K12 and Rhizobium trifolii.

The nitrate respiratory systems of both the facultative anaerobe Escherichia coli K12 strain W3350 and the aerobe Rhizobium trifolii strain T1 are regulated in a similar manner by a complex set of interactions involving H2, N2, CO2, glucose and nitrate. In addition, the nitrate respiratory system of strain T1 can be regulated by chlorate. A possible mechanism is presented to illustrate how these complex interactions might take place.


A modification of the polyethylene glycol technique for the purification of small quantities of tobacco mosaic virus.

An adaptation of the polyethylene glycol method for the purification of tobacco mosaic virus (sunnhemp strain) from small (2 g) samples of French bean lamina is described. The virus can be precipitated from 1-2 ml of clarified sap by the addition of an equal volume of 8% polyethylene glycol 6000 (w/v) (PEG), and pelleted by centrifugation for 10 min at 1,8000 x g. Details are given of tests which establish that the purity and quality of the virus obtained by the small-scale method are as good as those achieved by the established large-scale method. Even with very low virus titres, the small-scale method effectively precipitates total tobacco mosaic virus nucleoprotein without substantial loss of infectivity. The results are reproducible and in a relatively short time it is possible to purify the virus from large numbers of replicate samples.


Growth and survival studies of psychrophilic and mesophilic yeasts.

The effect of temperature on the growth of members of five genera of yeasts was studied in one glucose-containing and two glucose-free media. The maximum growth rate was seen in the glucose-containing medium, and the minimum growth was in either of the two glucose-free media depending upon the organism. Data obtained by optical density measurements was supported by total cell counts. The highest survival at the restrictive temperatures was within 5 degrees C of the optimum temperature for a particular organism. Among the temperatures other than the optimum, the highest growth rate and cell yield was obtained at a temperature 5 degrees C below or above the optimum.


Purification and properties of a protein surface antigen of Streptococcus mutants.

A protein, designated antigen III, was extracted from cells and culture supernatant of Streptococcus mutans serotype c, and purified by ammonium sulphate precipitation followed by chromatography on anion-exchanged and gel filtration columns. Monospecific antisera were raised by injecting purified antigen III in rabbits. Antigen III prepared from cells and supernatants appeared identical by reaction with antisera and were of similar chemical composition and physico-chemical properties. Antigen III was resistant to most proteolytic enzymes, but pepsin digestion decreased its molecular weight from 44,000 to 24,000 without destroying antigenic activity. Immunofluorescence showed that antigen III was located at or near the cell surface of S. mutans serotypes b, c, e and f.


[A modification of microglia impregnation (author's transl)].

A modification of the Weil and Davenport (1933) silver carbonate method for microglia impregnation is described. Formalin-dextran-CaCl2 solution was used as a fixation solution. The technique is simple, reproducible and improved. The staining method includes the demonstration of as well resting as progressive microglia.


Identification of beta-hemolytic streptococci isolated from hospitalized children in Baghdad.

Two hundred and twenty four hospitalized children in Baghdad aged between 1 month and 10 years were examined for Streptococcal infections. Thirty-four percent of the throat and saliva specimens were positive for beta-hemolytic streptococci. Males were more susceptible to infection with group A streptococci than females. Streptococcus of group A was isolated from 39.5% of the positive cases while group G was 47.4%. The etiological significance of the latter group in tonsillitis and otitis media is to be further investigated. Ninety six percent of the isolated streptococci were T typable and 13.3% of the strains were M typable. A high frequency of type T-11 was found in streptococcal infections. T type 3875 was found to be a new provisional type. All isolates were M untypable, and antiopacity factor negative except for two isolates of T type 4 which were positive in both typings.


"Pseudolysogenization" by RNA phage Q beta.

We isolated fairly stable lysogenic-like bacteria from a lysogenic state established between an amber mutant for the maturation protein gene of RNA phage Q beta (Q beta am 205) and its nonpermissive host BE110. These bacteria contained few mature phages intracellularly (less than 10(-3) plaque forming unit per cell), continued to grow with a potentiality to produce Q beta am 205 spontaneously, and showed an immunity-like response against homologous phage infection. These characteristics were maintained by growth in liquid medium containing anti-Q beta serum. We designated these cells as pseudolysogenic bacteria. The relative amounts of RNA genomes in these pseudolysogenic cells (about 10(2) infectious RNA strands per cell) indicated that the RNA genomes could replicate in nonpermissive cells and be distributed in daughter cells synchronizing well with cell division.


Local production of antisperm antibodies in infertile women.

The presence and significance of locally produced antisperm antibody in 20 well-documented infertile patients has been investigated. Sera and vaginal washings both from patients and from fertile controls were examined for antisperm antibody by means of four methods. Antisperm antibody was detected in 25% of the washings taken from infertile patients, but in none of those from fertile women. Detection of antibody by the microimmobilization technique discriminated best between infertile and fertile women both in serum (P=0.0166) and in washings (P=0.0166). The results of this study support the concept that locally produced antisperm antibody contributes to conception failure in a subgroup of infertile women, and that the routine study both of sera and of vaginal washings of infertile patients has practical value.


[Isolation of the intracellular lipase of Serratia marcescens].

Various methods have been tested in order to isolate endolipase from the cells of Serratia marcescens 345: cell disintegration by ultrasound and French press as well as incubation of the cellular suspension with sodium salts of bile acids. The combined effect of ultrasound and these salts on the cellular suspension of S. marcescens 345 was also studied. The highest lipolytic activity was found in the supernatant obtained upon incubation of the cells with sodium cholate at a concentration of 0.8% for 30 min.


[Search for life on Mars].

The paper presents the data about the catalytic activity of several minerals from the Martian ground and of some laboratory analogues of the planet ground. It has been shown that it is possible to obtain unambigious data about life on Mars by using such methodological approaches which are based on biological principles of the determination of living matter. Microbiological methods for detection of extraterrestrial life should be preferred in future over biogeochemical methods which were used by the Viking stations.