[The distribution of avian enteroviruses in Germany]

Sera from chicken flocks of different regions in Germany were examined for antibodies to avian nephritis virus (ANV) by indirect immunofluorescence. There was no evidence of a wide distribution of ANV, at least in chicken parent flocks, in contrast to results from investigations in England, Northern-Ireland and Japan.

[Primary ulcer of the small intestine. The value of peroperative endoscopy]

A case of primary non-specific small bowel ulceration in a 39-year-old man is reported. Because of massive bleeding, an exploratory laparotomy was performed and the jejunal ulcer was discovered by fiberoptic endoscopy through a small jejunal enterotomy. The authors review the literature about the incidence, the diagnostic approach, the pathology, the aetiopathogenesis and treatment of this rare disease.

[Infectious disease factors in poultry]

The increased importance of multicausal diseases of poultry in the present time is due to a better control and prevention of the monocausal diseases and epidemics predominant in the past. This development is supported by the intensive methods of modern poultry husbandry, the high stocking densities and the improved performance of the poultry by genetic selection. Opportunistic as well as pathogenic organisms can be involved in the development of infectious factorial diseases. A variety of clinical signs can be observed. Above all immunosuppression accompanied by mixed infections and other factors causes health problems of great economical importance. Frequently series of events take place in the development of infectious factorial diseases, in the course of which a preceding disturbance acts as factor of further diseases. Some examples of diseases and syndroms are given to substantiate the multiple involvement of different factors and infections in the development of series of events.

Biochemical, immunological and physicochemical comparisons between OHIO-1 and four SHV-type beta-lactamases

The biochemical, immunological and physicochemical properties of the beta-lactamase OHIO-1 were compared to those of four beta-lactamases commonly found in Klebsiella pneumoniae: SHV-1, SHV-3 and the beta-lactamases of strains GN 11-03 and GN 422. The substrate profile of SHV-1, OHIO-1 and of the beta-lactamases GN 11-03 and GN 422 were similar, while that of SHV-3 appeared comparable to that of the extended spectrum SHV-2. Moreover, anti-TEM-1 serum inactivated OHIO-1 as well as SHV-1 and the beta-lactamases of strains GN 11-03 and GN 422. Analysis of the electrophoretic mobilities, isoelectric points and titration curves demonstrated that OHIO-1 and the 4 other beta-lactamases examined were closely related variants. From these findings it appears that OHIO-1 could be classified among the SHV-type beta-lactamases.

The analysis of five carbenicillin-hydrolysing enzymes by electrophoretic methods

Five carbenicillin-hydrolysing enzymes (carbenicillinases, or CARB), PSE-4 (CARB-1), PSE-1 (CARB-2), CARB-3, CARB-4 and CARB-5, and the beta-lactamase PSE-2 were compared by analysing their isoelectric points (pI), electrophoretic mobilities (mR) and titration curves (pH gradient electrophoresis). The pI determined by isoelectric focusing were 4.3 (CARB-4), 5.3 (PSE-4/CARB-1), 5.7 (PSE-1/CARB-2), 5.75 (CARB-3), 6.1 (PSE-2) and 6.35 (CARB-5). Their mR were estimated by zone electrophoresis as congruent to 26 for PSE-1 (CARB-2), CARB-3 and CARB-5, congruent to 30 for PSE-2, congruent to 33 for PSE-4 (CARB-1) and congruent to 61 for CARB-4. Titration curve analyses indicated that (1) PSE-4 (CARB-1), PSE-1 (CARB-2), CARB-3 and CARB-5 are closely related variants differing by a few amino acid substitutions; (2) the qualitative titration curve of CARB-4 is different from those of PSE-4 (CARB-1), PSE-1 (CARB-2), CARB-3 and CARB-5, although their patterns are somewhat similar; and (3) PSE-2 has no structural relationship with any of the other carbenicillin-hydrolysing enzymes or carbenicillinases (CARB) studied. Electrophoretic methods, and in particular titration curve determination combined with other physicochemical and enzymatic data, allowed a rapid comparison of the molecular structures of the beta-lactamases, and hence their classification.

Analysis of the molecular relatedness of four extended spectrum beta-lactamases (SHV-2, SHV-3, SHV-4 and SHV-5) by comparative protein titration curves

Six beta-lactamases from Klebsiella pneumoniae, five of which (SHV-1, SHV-2, SHV-3, SHV-4 and SHV-5) were plasmid-encoded and one which (beta 1a GN 11-03) was chromosomally-encoded, were compared by analysis of their isoelectric points (pI), electrophoresis mobilities (MF) and titration curves or pH gradient electrophoresis. Four groups were defined by their pI and MF, namely SHV-1 and SHV-2 (pI = 7.6, MF approximately 14), SHV-3 and beta 1a GN 11-03 (pI = 7.0, MF approximately 20), SHV-4 (pI = 7.8 MF approximately 12) and SHV-5 (pI = 8.2, MF approximately 5). The titration curves of SHV-1 and SHV-2 enzymes on the one hand, and SHV-3 and beta 1a GN 11-03 on the other were completely superimposable for the whole of the pH gradient (3.5-10), indicating strongly similarity. Conservative amino-acid substitutions could account for the differences in the substrate spectra of the purified enzymes. The differences observed between the titration curves of the enzymes SHV-1/SHV-3, SHV-1/beta 1a GN 11-03, SHV-2/SHV-3 and SHV-5/SHV-4 pairs were consistent with the replacement of a basic amino-acid residue in the former enzyme of each pair by an acidic residue in the latter. Similarly, the titration curves of SHV-1/SHV-4 and of SHV-2/SHV-4 pairs may suggest the replacement of an acidic amino-acid in the former beta-lactamases by a neutral amino-acid in the latter of each pair. However, the presence of several self-cancelling or neutral substitutions is also possible. In contrast, when SHV-1 and TEM-1 (pI = 5.4 MF approximately 45) were titrated together, no structural relationship could be inferred.

Novel carbenicillin-hydrolyzing beta-lactamase (CARB-5) from Acinetobacter calcoaceticus var. anitratus

A strain of Acinetobacter calcoaceticus var. anitratus highly resistant to ticarcillin but susceptible to ticarcillin in combination with clavulanic acid (2 mg/l) was found to produce a constitutive beta-lactamase. This enzyme was periplasmic with a characteristic substrate profile of a carbenicillin-hydrolyzing enzyme. Enzyme inhibition was detected with antiserum (anti-CARB-3), pCMB, cloxacillin, clavulanic acid and sulbactam. This novel enzyme with a molecular mass of 28,000 resembles other plasmid-mediated carbenicillinases (CARB) but differs in its apparent isoelectric point estimated as 6.3 and has been designated CARB-5 on this basis.

Dissemination in five French hospitals of Klebsiella pneumoniae serotype K25 harbouring a new transferable enzymatic resistance to third generation cephalosporins and aztreonam

A strain of Klebsiella pneumoniae K25 resistant to newer beta-lactam drugs was isolated in clusters in five hospitals in the Paris area. The MICs of ceftazidime and aztreonam (greater than or equal to 128 mg/l) were higher than that of cefotaxime (16 mg/l) for the strain but, when measured in the presence of clavulanic acid, they were less than or equal to 1 mg/l. The donor strains and derivatives produced a beta-lactamase with a pI of 7.75-7.8 and hydrolysing activity against a wide spectrum of beta-lactams similar to that of SHV-2 and SHV-3, but with significant hydrolysis of ceftazidime. This new enzyme could be designated SHV-4.

[Plasmid resistance to 3d generation cephalosporins]

Beta-lactamases still play an important part in medical bacteriology, as shown by the emergence, since 1983, of plasmid-mediated beta-lactamases with an enlarged spectrum (SHV-2, CTX-1, etc.). Such enzymes are only produced by enterobacteria and, more specifically, by Klebsiella pneumoniae. This phenomenon, described in Europe and in Africa, is certainly more widespread than it would appear, as some strains are now known to be less sensitive to third generation cephalosporins (MIC 1 to 4 mg/l). Despite differences in behaviour (cefotaximase and ceftazidimase phenotypes), resistance to amino-, carboxy- and ureido-penicillins is associated with reduced sensitivity or resistance to oxyimino beta-lactams (cefotaxime, ceftriaxone, ceftazidime, aztreonam), but cefamycins and imipenem are untouched. Being sensitive to enzyme inhibitors (e.g. clavulanic acid), these beta-lactamases can easily be detected and some infections (notably urinary tract infections) can probably be treated using these inhibitors. These enzymes show modified kinetic constants (better affinity and quicker hydrolysis) against penicillins, third generation aminothiazolimino-cephalosporins and aztreonam. The producing strains are mutants, with aminoacid 1 to 2 substitutions, of those which produce the usual plasmid-borne and transposable beta-lactamases (TEM or SHV). Because these beta-lactamases are plasmid-mediated, enzyme production mechanisms are spreading among enterobacteria species in relation to other resistance markers (tobramycin, netilmicin, amikacin). Strains which produce these new enzymes are mainly isolated from patients treated in intensive care units.

Peptide histidine methionine (PHM) increases ileostomy output

The human vasoactive intestinal peptide (VIP) gene also encodes peptides histidine methionine (PHM) which has substantial sequence homology with VIP. Both are present in nerve fibers in the human ileum and circulate in greatly increased concentrations in patients with the watery diarrhoea syndrome. We have infused PHM (23 pmol/kg/min) into 5 patients with ileostomies to determine the effect of PHM on human ileal output. Plasma PHM levels rose from 22 +/- 6 to 6013 +/- 874 pM (mean +/- S.E.M.) during PHM infusions and ileal output rose from 16 +/- 3 to 177 +/- 27 g/30 min (P less than 0.0001). PHM infusions also produced a significant fall in the percentage of solid material and a rise in the concentration of chloride in the ileal effluent. Mean plasma PHM concentrations during PHM infusions were equal to the highest levels seen in patients with the watery diarrhoea syndrome, so PHM may contribute to diarrhoea in this condition. Neuronal PHM may exert physiological control over ileal transport of water and electrolytes.

Immunological comparison of constitutive beta-lactamases of gram-negative bacteria by neutralization in zymogram gels: properties of anti-TEM-1 and anti-TEM-2 sera

The zymogram technique was applied to a beta-lactamase neutralization assay with anti-TEM-1 and anti-TEM-2 sera. Both were shown to contain neutralizing antibodies directed towards various beta-lactamases of Gram-negative bacteria. The quantitative neutralization allowed classification into five groups of the 28 beta-lactamases used as standards and 61 from clinical isolates. In the first were enzymes such as TEM-1 and TEM-2 including TLE-1, SHV-1, SHV-2, penicillinases of Klebsiella pneumoniae and CTX-1. Partial neutralization distinguished two groups containing the CARB group of enzymes, which are different from PSE-2 and PSE-3, and the MAL penicillinases of Levinea malonatica, which are different from L. amalonatica enzymes. Broad spectrum beta-lactamases of K. oxytoca constituted a unique group of partially neutralized enzymes. Among the beta-lactamases not neutralized by either serum were the plasmid-mediated OXA-enzymes, various species-specific beta-lactamases and cephalosporinases. The antigenic similarities of the enzymes appeared to correlate with the extent of similarities of their catalytic properties, namely those of penicillinases. Such comparisons between the beta-lactamase groups provide an indirect approach to the physiological and structural analysis of established and recently evolved beta-lactamases.

[Titration curves (ph gradient electrophoresis) of SHV-1 and SHV-2 beta-lactamases and a new type]

The molecular structures of the SHV-1 (p 453) and SHV-2 (pBP 60-1) beta-lactamases and of a new enzyme, a SHV-2 like extended broad-spectrum beta-lactamase (86-4), were compared by analysis of their titration curves (pH gradient electrophoresis). The titration curves of SHV-1 and SHV-2, which have the same isoelectric points (pI = 7.7). were completely superimposable for the whole of the pH gradient (pH 3.5-10), indicating a close homology between the two proteins, with perhaps the substitution of several amino acids by ones having the same charge. The curves of SHV-1 (pI = 7.7) and the new SHV-2-like enzyme (pI = 6.98) indicated that a basic residue in SHV-1 has been replaced by an acidic residue in the new SHV-2-like enzyme. These results show that, like SHV-2, the new beta-lactamase is a variant of SHV-1, and that the structural differences are probably limited to a very small number of amino acid residues. Nevertheless, this new beta-lactamase (SHV-3) may have arisen directly from SHV-1, indirectly via SHV-2, or even from another beta-lactamase.

[Electrophoretic behavior of beta-lactamases in gram-negative bacteria]

The ongoing discoveries of new beta-lactamases, mainly penicillinases, in Gram-negative bacteria has emphasized the problem of their precise identification, and thus their phylogeny. Crude extracts, prepared by sonication, of 14 plasmid beta-lactamases, types TEM, carbenicillinases (CARB or PSE) and oxacillinases (OXA) were analysed by a simple, rapid (3.5 to 4 hours) method of electrophoresis on polyacrylamide (7%) agarose (1.4%) gels, using Tris-glycine buffer at pH 8.7. Preliminary serial dilutions were made to determine enzymic activity levels. Enzymes were then characterized by their relative electrophoretic mobilities. These mobilities had coefficients of variability between 2% and 10%, ranged from 5 to 61, and were correlated with their isoelectric points (pI). Thus, the lower the pI is, the greater the mobility is. Despite the high resolving power of the polyacrylamide-agarose gel system, enzymes with similar pI's and of similar types (PSE-1 and CARB-3, or OXA-1 and OXA-4) or different types (SHV-1 and OXA-6) could not be distinguished on the basis of their mobilities. However, this technique provides for rapid and easy identification of the major penicillinases in Gram-negative bacteria. A combination of polyacrylamide-agarose gel electrophoresis and pH gradient electrophoresis (titration curve) could provide a powerful approach to the study of the molecular structure of these enzymes.

[Human Pasteurella multocida infections. Value of serological diagnosis]

In five human cases of Pasteurella multocida infection, high titres of specific antibodies were found by indirect haemagglutination (capsular antigens) and agglutination (somatic antigens). The specificity of the antibodies fitted with the serotypes of the isolated strains (three A 3 and two A 7). Subsequent changes in antibody titres in human beings were similar to those observed in animals. The risk of this animal-acquired infection being probably underestimated in medical practice, the usefulness of these tests in human beings is discussed.

Sequence of the halobacterial glycosaminoglycan

The cell-surface glycoprotein of halobacterium contains a sulfated repeating unit saccharide chain, similar to the mammalian glycosaminoglycans. The composition of a presumptive repeating pentasaccharide unit of this glycosaminoglycan is 1 GlcNAc, 1 GalNAc, 1 Gal, 1 GalA (where GalA represents galacturonic acid), 1 3-O-methyl-GalA, and 2 SO42-. Linkage to protein of this glycoconjugate involves the hitherto unique unit Asn-GalNAc, with the N-linked asparagine residue being the second NH2-terminal amino acid and part of the common N-linked glycosyl acceptor sequence Asn-X-Thr(Ser). Transfer of the completed, sulfated glycosaminoglycan from its lipid precursor to the protein occurs at the cell surface, and the presence of this sulfated saccharide chain in the cell-surface glycoprotein seems to be required to maintain the structural integrity of the rod-shaped halobacteria. In this paper, we report the complete saccharide structure of this N-linked glycosaminoglycan. This structure is deduced from chemical analyses of fragments that were isolated after hydrazinolysis and subsequent nitrous acid deamination or after mild acidic hydrolysis of purified Pronase-derived glycosaminoglycan-peptides. The halobacterial glycosaminoglycan consists, on the average, of 10 repeating pentasaccharide units of the following structure. (formula: see text) The reducing end N-acetylgalactosamine residue is linked directly to the asparagine, without a special saccharide linker region.

[Titration curves of beta-lactamases using pH gradient electrophoresis]

The molecular relationships of two types of plasmid-mediated beta-lactamases, TEM-1 (R 111), TEM-2 (RP 4) and OXA-1 (RGN 238), OXA-4 (pMG 90) were analysed by combined isoelectrofocusing-electrophoresis. Titration curves of TEM-1 (pI 5.4) and TEM-2 (pI 5.6) together were consistent with the known substitution of a glutamic acid in the former by a lysin in the latter. When OXA-1 (pI 7.4) and OXA-4 (pI 7.45) were titrated, one single mobility curve was obtained reflecting their structural homogeneity. The titration curve technique will be usefull for the study of structure of beta-lactamases.

Specific antibody response to Pasteurella multocida

Six patients with culturally proven Pasteurella multocida infection were evaluated serologically. The infections were 1 foot abscess, 1 septicemia, 3 bronchitis and 1 bronchopneumonia. Most of them were elderly women closely exposed to pets or domestic animals. The serotypes of the strains were determined in 5 cases (3 A3, 2 A7). Specific antibodies against capsular and somatic antigens of P. multocida were determined by indirect hemagglutination and agglutination respectively. The antibodies were strictly directed against the capsular and somatic specificities of the isolated strain. The range of the serum antibody titers were 20 to 2,560 to capsular antigens and 5 to 640 to somatic antigens within 2 weeks after the first clinical signs of infection. Several months after successful treatment, the capsular antibodies were lower while the somatic antibodies had almost disappeared. These findings suggest a good sensitivity for these serologic methods in active cases. Declining antibody titers follow healing. Cross-reactivity of the serologic tests with other bacteria was not observed. Serologic diagnosis of P. multocida infections is a possible alternative to direct diagnosis when cultures are negative or when unusual localizations must be confirmed.

[Mechanism of enzymatic resistance to beta-lactam antibiotics]

The resistance of bacteria, particularly Gram-negative bacteria, to beta-lactam antibiotics is principally caused by enzymes. Beta-lactamases inactivate these antibiotics by opening, more or less rapidly, the beta-lactam ring. The chronology of therapeutic discoveries is governed by natural and acquired resistance. The first step was to establish the characteristics of beta-lactamases (location, biogenesis, enzymatic profile, affinity constant, inhibition profile, isoelectric point, molecular weight, genetic determination, etc.). Advances in the selection of natural or semi-synthetic compound are centred on the following points: increased stability to beta-lactamases, inhibitory effect, reduced inducibility, low affinity for the enzyme, greater speed of penetration through the bacterial wall, increased tropism for targets. Notable among the new beta-lactam antibiotics are acylureidopenicillins, beta-lactamase inhibitors and carbapenems. The antibacterial activity of third generation cephalosporins is 10 to 1000 times higher than that of previous cephalosporins; the result is a wider spectrum including, in particular, cephalosporinase-producing organisms. Concerning acquired resistance, the behaviour of new antibiotics must be examined by comparing the minimum inhibitory concentrations of isogeneic and clinical strains, and according to phenotype or mechanism: sensitive, penicillinase producer, cephalosporinase producer or producer of both penicillinases and cephalosporinases. During synthesis of a penicillinase, penicillins and some cephalosporins are more or less inactivated. With a constitutive cephalosporinase, all cephalosporins are inactivated as are, to a lesser degree, penicillins and monobactams, e.g. aztreonam. The emergence of new enzymes, including broad-spectrum beta-lactamases, and their extension to sensitive bacteria show that the enzymatic mechanism still has potentials for development.

Characterization of a beta-lactamase from Pasteurella multocida

A bovine strain of Pasteurella multocida was found to produce a beta-lactamase. The minimal inhibitory concentrations of amoxicillin (128 mg/l) and ticarcillin (512 mg/l) were high for this strain. The enzyme was periplasmic and produced constitutively, and there was no obvious permeability barrier. This enzyme had a TEM-substrate profile, and no inhibition was detected with antisera (anti-TEM-1, anti-TEM-2). The apparent isoelectric point was estimated at 8.8.

Incidence and aetiology of fractures of the facio-maxillary skeleton in Trivandrum: a retrospective study

A retrospective look at the incidence and aetiology of fractures of the facio-maxillary skeleton over a 2 year period was carried out in the department of Oral and Maxillofacial Surgery, Dental College, Trivandrum, India.

Asparaginyl-N-acetylgalactosamine. Linkage unit of halobacterial glycosaminoglycan

The cell surface glycoprotein of Halobacteria contains two different types of sulfated saccharides: hexuronic acid-containing oligosaccharides linked to the protein via asparaginylglucose, and a serially repeated saccharide unit containing amino sugars that resembles the animal glycosaminoglycans. Here we report that 1) the sulfated repeating unit saccharide is linked to the cell surface glycoprotein via asparaginyl-N-acetylgalactosamine, 2) the amino acid sequence surrounding this linkage region is -Asn-Ala-Ser-, and thus in agreement with the acceptor sequence ASN-X-Thr(Ser) common to all eucaryotic N-glycosidically bound saccharides determined so far; 3) in addition to galactose, galacturonic acid, N-acetylglucosamine, and N-acetylgalactosamine, the methylated hexuronic acid 3-O-methylgalacturonic acid occurs as a stoichiometric constituent of the sulfated building block of the glycosaminoglycan chain.

[Bacterial flora in gastric juice taken at endoscopy in 93 normal subjects]

Bacteriologic examination of gastric juice samples taken during endoscopy in ninety-three subjects free of endoscopically-detectable disease was performed. Mucosal pH was determined using bromocresol green dye. Among the 17 subjects with a mucosal pH exceeding 4, 11 (64%) had more than 10(5) organisms/ml. In contrast, similar counts were found in only 10 of the 76 subjects with a normal mucosal pH. The pathogens recovered were normal hosts of the upper digestive tract and a few nitrate reductase + Enterobacteriaceae. Questions still to be resolved are whether these pathogens can induce disease and whether bacterial colonization correlates with the increased gastric nitrosamine levels and microscopic mucosal lesions previously described in patients with a gastric pH above 4.

Halobacterial flagellins are sulfated glycoproteins

The cell-surface glycoprotein of Halobacteria contains oligosaccharides of the type Glc4----1GlcA4----1GlcA4----1GlcA (where GlcA indicates glucuronic acid) with a sulfate group attached to each of the GlcA residues. We report here that in addition to this cell-surface glycoprotein, the halobacterial flagellar proteins (recently described by Alam, M., and Oesterhelt, D. (1984) J. Mol. Biol. 176, 459-475) also contain the same type of sulfated oligosaccharides. These flagellins have the following features. All of the individual flagellar proteins contain identical sulfated saccharide moieties linked to the amido nitrogen of Asn through a Glc residue (the novel type of N-glycosidic linkage that has been found in the cell-surface glycoprotein from Halobacteria (Wieland, F., Heitzer, R., and Schaefer, W. (1983) Proc. Natl. Acad. Sci. U.S.A. 80, 5470-5474)). The amino acid sequence of one carbohydrate-binding region is Gln-Ala-Ala-Gly-Ala-Asp-Asn-Jle-Asn-Leu-Thr-Lys. This surrounding sequence CHO is consistent with the general formula Asn-X-Thr(Ser), common to all N-linked glycopeptides determined so far. Biosynthesis of flagellar glycoconjugates involved sulfated oligosaccharides linked to dolichol monophosphate. The individual glycoproteins making up the flagella are structurally closely related to one another.

[Enterobacter cloacae and E. aerogenes septicemia: emergence of resistant variants (derepressed cephalosporinase) during treatment with third-generation cephalosporins]

From three patients hospitalised in intensive care units with Enterobacter septicaemia (two cases with E. cloacae, and one with E. aerogenes), cefotaxime therapy, alone or in combination with an aminoglycoside, selected variants (R) with increased resistance to beta-lactam antibiotics. The cross-resistance extended to all the beta-lactam antibiotics tested, penicillins and cephalosporins, including third-generation cephalosporins. The crude extracts of uninduced cultures of R variants showed high beta-lactamase activity and of the cephalosporinase type. These variants were selected in vitro with a frequency of 10(-6) to 10(-7) and may result from a mutation involving the regulation of Enterobacter cephalosporinases, usually inducible. Data from the literature indicated that this new type of resistance is actually emerging and observed not only in Enterobacter sp. The problem of emergence of R variants exhibiting cross-resistance to beta-lactam antibiotics should be considered when third-generation cephalosporins are used.

[Antibiotic sensitivity test. Comparative multicenter study of the gel diffusion and ATB methods]

The ATB method is a new method for antibiotic susceptibility testing. In a collaborative study, it was compared to a standard disc diffusion method. 23 strains were tested to determine reproducibility and 969 strains were used in the comparative study. Reproducibility of both methods is equivalent; differences due to strains were observed. Agreement between both methods is 87,9%, minor discrepancies are 8,7% and major discrepancies are 3,3%. Significant differences were found for carbenicillin and cefalotin and confirmed by MIC determination using the agar dilution method. Overall results show that the ATB method is reliable and comparable to disc diffusion for routine susceptibility testing.

[Enterobacter cloacae. In vivo emergence of a variant resistant to new beta-lactams during treatment with lamoxactam-gentamicin]

In a patient recently operated for an abdominal gun wound, and given gentamicin-cephalosporin (cefoxitin for one day, then moxalactam) for 11 days, treatment failed as a result of emergence of a E. cloacae variant resistant to beta-lactams only, i.e. carbenicillin, mezlocillin, cefamandole (CFM), cefoperazone (CPZ), cefotaxim (CTX) and moxalactam ( MOX ). The initial susceptible strains isolated from blood cultures (SH1, SH2) and the resistant ones isolated 11 days later from pancreatic pus (RP) and blood cultures ( RH1 , RH2 ) shared the same chemotype. MICs of CFM, CPZ, CTX, and MOX were much higher (1 000 to 4 000 fold) for RH1 than for SH1. The biochemical mechanism of resistance showed the six following features: loss of antimicrobial activity of CFM, CTX and MOX added to RH1 cultures; much higher (1 500 fold) beta-lactamase activity for RH1 than for SH1 (iodometric and microacidimetric methods); beta-lactamases focusing at the same pl (greater than 8) produced by RH1 , RP and also, but only after induction, SH1 and SH2; cephalosporinase-type beta-lactamase according to the enzymatic activity profile; restoration of RH1 's susceptibility to CFM, CTX and MOX merely by adding cloxacillin; apparently unchanged crypticity for RH1 . The enzymatic mechanism (cephalosporinase hyperproducing variant) seems very likely.

[Beta-lactamases of ampicillin-resistant Salmonella]

One hundred and five strains of Salmonella, including 103 clinical isolates, were examined for resistance to beta-lactams (ampicillin, carbenicillin). The resistance frequency was 5.9 and 40.6%, respectively, according to the geographical source: France or Senegal. The mechanism of resistance to beta-lactam antibiotics was always related to the biosynthesis of one constitutive beta-lactamase (beta la+). By analytical isoelectric focusing on gel of all crude sonic extracts, four types of enzymes were identified: TEM-1, TEM-2, OXA-1 and SHV -1. TEM-1, the most prevalent, was observed among 17 serotypes, TEM-2 among 3 including S. poona , and OXA-1 among 2 serotypes. SHV -1 was detected in all isolates of S. ordonez (38) but only among strains of this serotype. Among others factors involved in their distribution, differences were reported according to the geographical origin of the studied strains. In France, the three types, TEM-1, TEM-2 and OXA-1, were isolated only in the north. Moreover, the resistance frequency was 4-fold higher (7.3%) than in the south (1.8%). In Africa (Senegal), three types were individualized: TEM-1, TEM-2 and SHV -1. The SHV -1 type was only detected in clinical isolates of S. ordonez from Senegal, all of which were multi-resistant to other antibiotics (chloramphenicol, sulfonamides and tetracyclines).

Tinnitus asymmetry

In the present study, the relationship between the location of tinnitus and the location of the greater hearing impairment was investigated. 62 subjects suffering from tinnitus underwent audiometric testing and were required to identify the location of their tinnitus. All of the subjects had a history of exposure to loud noise. The results of the study showed an asymmetric relationship between the variables examined. Most of the subjects with a greater hearing loss on the right side reported right-sided tinnitus, while the majority of subjects with a greater loss in the left ear reported tinnitus heard identically in both ears or tinnitus heard louder on the right side. An assumption was made that this phenomenon is related to differential hemispheric responsiveness to abnormal neural activity arising in the peripheral parts of the auditory system as a result of cochlear damage, activity which is the presumed origin of neurogenic tinnitus.

Nosocomial infections by chlorhexidine solution contaminated with Pseudomonas pickettii (Biovar VA-I)

Over a period of 10 days, six patients in a cardiac intensive care unit developed Pseudomonas pickettii (biovar VA-I) septicaemia after installation of a venous catheter. The organism was also recovered from all the vials of the aqueous solution of 0.05 per cent chlorhexidine ('Hibitane') prepared with contaminated bidistilled water. There were no further cases of infection when the use of this water was prohibited.

Tinnitus pitch and acoustic trauma

56 Subjects complaining of tinnitus underwent an audiometric test and a test for identifying the analogous pitch of their tinnitus. All of the subjects reported that they had been exposed to noise in the past. The subjects were divided into two groups on the basis of their audiometric test results. Group P was composed of subjects who showed a sensorineural hearing loss typical of acoustic trauma. Group N was composed of subjects whose hearing was within normal limits. The pitch of the tinnitus in group P was concentrated in the high-frequency range, whereas in group N tinnitus pitch values were distributed over the low and mid-audiometric frequency spectrum. It was deduced that different processes are involved in the generation of tinnitus in the two groups.

[Rapid determination of the synergy of clavulanic acid and beta lactams by measuring the intracellular ATP by bioluminescence]

Twenty clinical isolates of ampicillin- and carbenicillin-resistant or susceptible (two strains) Gram-negative rods, producing at least one beta-lactamase, were examined for susceptibility to a combination of ampicillin or carbenicillin with clavulanic acid (enzymatic inhibitor). Synergy was evaluated by the reduction of the beta-lactam agar dilution MIC and by the measurement of intracellular AYP using firefly bioluminescence. The potentiation effect of clavulanic acid was variable, depending on resistance levels, species and types of beta-lactamase (TEM, SHV-1, CARB, OXA, MAL and Cpase). The synergy was significant, with 10 mg/l of inhibitor for all the strains producing TEM-1, TEM-2 and Carb-2 except for one strain of Serratia marcescens (TEM-2). The synergy was weak for Levinea strains (Citrobacter diversus biotype b), biosynthesizing specific penicillinases as MAL-1. No potentiation effect was observed for strains producing a cephalosporinase, such as Escherichia coli and Pseudomonas aeruginosa. This effect appeared to be variable for strains producing the oxacillin-hydrolysing enzyme (OXA-1), such as E. coli and P. aeruginosa. A positive correlation was clearly demonstrated between the MIC values and the intracellular ATP concentration in bacteria within 2 h. The opportunity of using the firefly assay for the rapid determination of synergy between beta-lactam antibiotics and clavulanic acid is discussed.

Paternity testing: analysis of six blood groups and HLA markers, with particular reference to comparison of races

Blood groups (ABO, Rh, MNSs, Kell, Duffy, and Kidd) and HLA markers were tested in cases involving 563 children of disputed parentage. In 149 (26.5%) cases, the accused men were excluded as the biologic fathers of the children in question. One hundred forty of the 149 exclusions were direct exclusions. Five exclusions were based on red blood cell data alone, i.e., HLA was non-exclusionary. Of the remaining 414 cases in which the alleged father could not be excluded as the biologic father, in 361 (87.2%) instances, the plausibility of paternity ws 95% or greater, and in 385 (93.0%) instances the comparison of men value was 20 or greater. Caucasians, blacks, and men of other races were involved in 367 (65.1%), 185 (33%), and 11 (1.9%) cases, respectively. No significant difference among races was observed in the rate of exclusion of accused men. However, of the non-excluded men, in a significantly greater proportion of black men than white men, the plausibility of paternity was below 95%. The difference was probably due to lower polymorphism of the markers tested in blacks than in whites. It is suggested that tests for additional polymorphic genes be directed towards the 12-15% of the nonexclusionary cases with plausibility of paternity values below 95%.

[Rapid bioassay of gentamicin by bioluminescence (author's transl)]

Assay of bacterial intracellular ATP levels using the firefly bioluminescence system allows a very sensitive monitoring of bacterial growth. This test has been used in some laboratories fro performing a rapid microbiological assay of the concentration of antibiotics in the serum of treated patients. Rapidity of antibiotic determination is especially important in the case of antibiotics for which therapeutic concentration are close to toxic concentration. In the present work we have used the bacterial strain Klebsiella edwardsii var. atlantae for a rapid assay of gentamicin in the serum. We show that this assay is very accurate in the range of therapeutic serum concentrations. It may be readily performed in a routine laboratory with commercially available ATP extractors and luciferine-luciferose mixtures. This assay has been shown to correlate optimally with the classical plate diffusion assay (r = 0,983) and to be independent of the presence of beta-lactams in the serum.