Biomedical subjects

J Etienne

Publications and source records attributed to J Etienne.

At least 199 records · Page 11Linked to original sources

PubMed1992

Induction of a putative laminin-binding protein of Streptococcus gordonii in human infective endocarditis.

There is evidence to suggest that the virulence of Streptococcus strains in infective endocarditis might be due to the expression of binding sites for the extracellular matrix proteins of damaged valves. In this communication, we draw attention to one laminin-binding protein from a strain of Streptococcus gordonii isolated from a patient with human endocarditis. This 145-kDa protein was found on the cell wall of the bacterium. The level of expression of this binding protein might be regulated by the presence of extracellular matrix proteins: the protein was lacking after in vitro selection of laminin, collagen I, and fibronectin nonbinding variants, and it was recovered after growth of the variants when laminin or collagen I was added to the growth medium. It was also missing after 10 subcultures in minimal medium, indicating some positive control. Furthermore, the 145-kDa protein was recognized as a major antigen by sera from patients treated for streptococcal infective endocarditis, while sera from patients with valvulopathies gave only slight recognition, suggesting an increase of the expression of this protein during infective endocarditis. It was also shown that the 145-kDa protein carried a collagen I-like determinant detected with anti-human collagen I antibodies.

Collagen↗

PubMed1992

Description and evaluation of the semiautomated 4-hour rapid ID 32 Strep method for identification of streptococci and members of related genera.

The rapid ID 32 Strep system (bioMérieux, La Balme les Grottes, France) is a new system which allows the identification in 4 h of most streptococci and members of related genera encountered in medical and veterinary bacteriology. Four hundred thirty-three isolates first identified by conventional methods and belonging to the genera Streptococcus, Lactococcus, Enterococcus, Aerococcus, Gemella, Leuconostoc, Erysipelothrix, Gardnerella, and Listeria were tested. Overall, rapid ID 32 Strep correctly identified 413 (95.3%) of the strains, with 109 (25.1%) requiring extra tests for complete identification. Sixteen strains (3.7%) were not identified, and 4 (1.0%) were misidentified. The rapid ID 32 Strep system is a suitable alternative for rapid identification of members of the genus Streptococcus and of related genera.

Bacterial Typing Techniques↗

PubMed1992

[Genes of the lipase family: comparison of nucleic and proteinic sequences].

Vertebrates' plasmatic apolipoproteins and a few number of lipases in their metabolism present sequence homologies. They are grouped in genes families. The four exons apolipoproteins gene family includes nine human genes: the divergence rate of their sequences allows to place the first ancestral gene very high in the phylogenetic tree of the evolution. However, a more recent duplication of apolipoprotein C-I gene dating from 40 millions years, may be a phylogenetic marker for the radiation of Monkeys. Pancreatic lipase and isoforms, lipoprotein-lipase and hepatic triacylglycerol-lipase form by their homologies a "superfamily" of genes, which also includes yolk proteins of Dipterians eggs. Sequence homologies of PL, LPL and HL are analysed and compared with multiple alignments of amino-acids and nucleotides on spreadsheets. From these comparisons we may characterize four classes of phylogenetic markers: 1) repetitive DNA sequence (Alu, B1, PRE-1) appeared during Mammals evolution, 2) short insertions or deletions (within N-terminal domain) and a gene conversion in guinea-pig lineage, 3) a progressive reduction of intron number during the lipases evolution, 4) several duplications of genes which have produced the five genes of this superfamily currently known in the human genome.

Amino Acid Sequence↗

PubMed1992

[Lipoprotein lipase deficiencies].

Lipoprotein lipase (LPL) is an enzyme which plays a major role in the metabolism of circulating triglyceride-rich lipoproteins. It hydrolyzes chylomicron and VLDL triglycerides, thereby delivering fatty acids to tissues for storage or oxidation. In order to gain insight into the molecular basis of LPL deficiency, the structure of the LPL gene (ten exons and nine introns spanning about 30 kb) is first set out in relation to the different domains of the LPL protein. There is a high sequence homology between the aminoacids of LPL and of other lipases, such as hepatic triglyceride lipase (HL) and pancreatic lipase (PL). The PL catalytic triad Ser132, Asp156, His241 is also present in LPL. Absence of LPL activity can result from absence of LPL protein synthesis (Brunzell class I), or from the synthesis of an LPL protein devoid of enzymatic activity consequently to a mutation (class II). LPL can also be unable to bind to endothelial cells--a defect combined with deficient enzymatic activity--(class III). Among the known mutations of the LPL gene (such as nonsense, frameshift, abnormality in intron-exon junction, deletion, duplication) resulting in pathological cases, the most frequent are punctual mutations located mainly in exons 4, 5 and 6, leading to the substitution of an aminoacid for another in essential domains of LPL. The combined deficiency LPL + HL has also been described. The study of the abnormalities of the LPL gene, known only since the years 1990-1991, allows not only to better understand the pathology of LPL deficiencies, but also to point out which aminoacids play a major role in LPL activity.

DNA Mutational Analysis↗

PubMed1992

[Infectious agents associated with exacerbations of chronic obstructive bronchopneumopathies and asthma attacks].

Infections of the respiratory airways are frequently responsible for exacerbations of chronic obstructive pulmonary disease (COPD) and attacks of asthma. However, the causal infectious agents in practice are rarely precisely identified. We have undertaken a prospective study with the aim of researching into the bacteria and viruses associated with these exacerbations. Forty-seven patients who were in hospital between 1987 and 1989 for attacks of asthma (13 episodes) or exacerbations of COPD (35 episodes) were included in this study. The microbiological analysis consisted of: 1) the bacteriology of expectorated material or the products aspirated by fibroscopy with direct examination, quantitative cytology and culture; 2) samples taken from the nasal airways to identify and isolate pneumotropic viruses and mycoplasma; 3) serial serology looking for antibodies against pneumotropic bacteria and viruses. One of more infectious agents were shown in 47% of the episode studies of which 57% were exacerbations of COPD and treated 23% attacks of asthma. In the cases COPD bacteria were identified in 13 cases including Haemophilus influenzae [3], Streptococcus pneumoniae [3], Pseudomonas aeruginosa [3]. Amongst the 14 viruses recovered, the influenza virus [8] and the respiratory syncytial virus (VRS) [4] predominated. In 14 cases of acute asthma only 4 infectious agents were shown; Mycoplasma pneumoniae, influenza A, VRS and parainfluenza virus. The influenza virus was the agent most frequently discovered (26%) during the course of exacerbation of COPD and of asthma.

Bacteria↗

PubMed1992

Evaluation of a blood culture medium BHI-S-Lysis for BCB Release System Roche.

The new blood culture medium BHI-S Lysis for the BCB Release System (F. Hoffmann-La Roche AG., Basel, Switzerland), which lyses blood cells, was compared with the Hémoline performance Duo (BioMérieux, Marcy l'Etoile, France) including a diphasic medium and a modified Wilkins Chalgren broth. A total of 1998 sets were each inoculated with 7 ml of blood. In the laboratory, agar-coated paddles were attached to the BHI-S-Lysis. Overall, there was a statistically significant difference between the BHI-S-Lysis and the diphasic medium, or Wilkins Chalgren broth, in the recovery of clinically important microorganisms. The yield of pathogens with the BHI-S-Lysis, diphasic medium and Wilkins Chalgren broth was 115, 68 and 58, respectively. Staphylococci were detected by the BHI-S-Lysis significantly more frequently. Out of 50 bacteraemias, 12 were diagnosed with the BHI-S-Lysis only, three with the diphasic medium only, and three with the Wilkins Chalgren broth only. Contaminant isolates occurred with significantly greater frequency in the BHI-S-Lysis than in the two BioMérieux systems, in particular with coagulase-negative staphylococci. No speed advantage was present for all groups of micro-organisms and blood culture media. This good performance of the BHI-S-Lysis medium in detecting a larger number of pathogens should be confirmed by further evaluations.

Bacteremia↗

PubMed1991

Characterization of staphylococcal plasmids hybridizing with the fosfomycin resistance gene fosB.

The distribution of the fosB gene, coding for fosfomycin resistance, in 105 fosfomycin-resistant isolates of Staphylococcus from various geographical areas, was studied by Southern blot hybridization. Nucleotide sequences related to fosB were detected in 36 strains belonging to five species. Plasmids bearing fosB were often of a size similar to that of pIP1842 (2.54 kb) in S. epidermidis, most often small (2.4 to 4.1 kb) in other species including S. aureus where a 2.7-kb plasmid was found in 16 out of the 18 strains studied. The fosB gene was geographically dispersed since it was present in six different locations in France and also in Japan. The weak hybridization observed with plasmid DNA of certain strains of S. aureus, S. epidermidis, S. haemolyticus, S. saprophyticus, and S. warneri may indicate gene heterogeneity for fosfomycin resistance in Staphylococcus spp.

Blotting, Southern↗

PubMed1991

Long-acting chloramphenicol versus intravenous ampicillin for treatment of bacterial meningitis.

In most developing countries, bacterial meningitis (BM) is associated with a high case-fatality rate. The search for a simple, convenient, and inexpensive antibiotic treatment remains a priority. In this study, a non-blinded, multicentre, randomised clinical trial of 528 cases of BM was done in two hospitals in Mali and Niger, between March, 1989, and May, 1990, to see whether a double injection of long-acting chloramphenicol (on admission to hospital and 48 h later) is as effective as a course of intravenous ampicillin (8 days, 4 times a day). The cumulative case-fatality rate on day 4 (principal end-point) among the chloramphenicol (254 patients) and ampicillin (274) groups were, respectively, 28% and 24.5% (relative risk 1.14, 95% confidence interval 0.86-1.52). No outbreak occurred during the study period. The hospital case-fatality rate was 33.1%. Main risk factors for death were associated with clinical condition on admission--ie, altered consciousness, convulsions, or dehydration. The case-fatality rates were 13% (21/161) for Neisseria meningitidis, 36.1% (48/133) for Haemophilus influenzae, and 67% (77/115) for Streptococcus pneumoniae. In a multiple logistic regression model, controlling for the differential distribution of potential risk factors (including bacterial species), there was no difference between treatment groups. Our findings suggest that long-acting chloramphenicol is a useful first-line presumptive treatment for BM in high-incidence countries.

Ampicillin↗

PubMed1991

Recombinant human interleukin-1 suppresses lipoprotein lipase activity, but not expression of lipoprotein lipase mRNA in mesenchymal rat heart cell cultures.

The effect of human recombinant interleukin-1 (IL-1) on the regulation of lipoprotein lipase (LPL) was studied in rat heart mesenchymal cell cultures. A time-dependent reduction in enzyme activity occurred with a 30% fall after 1 h. The suppression of enzyme activity was accompanied by a commensurate reduction in enzyme mass. The reduction in LPL activity was most prominent in the heparin releasable pool; IL-1 treatment resulted in a 7.2-8.3-fold decrease in the functional compartment and a 2.5-2.8-fold decrease in residual cellular activity. The effect of IL-1 could be prevented by the addition of the IL-1 inhibitor. However, in contradistinction to the effect of tumor necrosis factor (TNF), there was no change in LPL mRNA in cultures treated with IL-1. The present results show that the regulation of LPL in mesenchymal heart cell cultures by IL-1 occurs posttranscriptionally, as has been shown in 3T3 cells. The more pronounced effect on LPL activity in the functional pool suggests that IL-1 treatment might have influenced also the processing and/or transport of the enzyme to the cell surface.

Animals↗

PubMed1991

The expression of lipoprotein lipase activity and mRNA in mesenchymal rat heart cell cultures is modulated by bFGF.

The effect of basic fibroblast growth factor (FGF) on lipoprotein lipase (LPL) production was studied in mesenchymal rat heart cell cultures. Addition of FGF to culture medium containing 20% serum resulted in a 3-fold increase in LPL activity. The minimal effective dose of FGF was 10 ng/ml and the increase occurred after exposure for 48 h. Addition of FGF was effective during the first week in culture, when enzyme activity was increasing, but not after 11 days when the cultures were superconfluent and the enzyme activity was high. Addition of FGF to serum-poor medium was able to replace serum required to sustain LPL activity. In FGF-treated cultures, more LPL activity was present in the functional pool, but not in the medium, than in the controls. The increase in enzymic activity was accompanied by an increase in enzyme mass and in LPL mRNA.

Animals↗

PubMed1991

Effect of magnesium deficiency on post-heparin lipase activity and tissue lipoprotein lipase in the rat.

Previous studies have provided evidence that Mg deficiency affects lipid metabolism. The present experiments were designed to assess whether the hypertriglyceridemia associated with Mg deficiency was related to alterations in post-heparin lipase activity (PHLA). Mg-deficient and control diets were pair-fed to weanling Wistar rats for eight days and plasma lipoproteins were separated into various density classes by sequential preparative ultracentrifugation. Triglycerides were significantly increased in chylomicrons and in the very low density lipoprotein, low density lipoprotein and high density lipoprotein (HDL) fractions. Cholesterol and phospholipid levels were significantly lower in the HDL fraction. PHLA in deficient rat was substantially lower than in control rats. The inverse correlation between plasma triglyceride concentration and PHLA strongly suggests that hypertriglyceridemia is the result of defective lipolysis of plasma triglycerides in Mg-deficient rats. Further examination of the PHLA was carried out by salt-mediated inhibition of lipoprotein lipase (LPL) and by heparin sepharose affinity chromatography and purified rat LPL antiserum. The results indicate that hepatic lipase is significantly decreased in Mg-deficient rats but the low PHLA is due mainly to a decline in LPL. However, total LPL activity, that is, both the intracellular and the extracellular pools of LPL in adipose tissue, heart and diaphragm, were unaffected by Mg deficiency. The results suggest that the decrease of LPL activity in the plasma of Mg-deficient rats may be due to a selective decrease in the heparin-releasable pool of enzyme.

Adipose Tissue↗

PubMed1991

Ivor Lewis operation for epidermoid carcinoma of the esophagus.

One hundred patients, 95 men and 5 women with a mean age of 59 years (age range, 35 to 77 years), were treated by the same initiate surgeon in practice from 1982 to 1988 for epidermoid carcinoma of the lower two-thirds of the esophagus using the Ivor Lewis procedure. Fifty-eight tumors were located in the middle third of the esophagus and 42, in the lower third. Postoperative staging revealed 30 stage I/II and 70 stage III carcinomas (ie, tumors extending beyond the esophageal wall or lymph node extension). Operative procedure was considered curative in 70 patients and palliative in 30 patients. The same procedure has been used for all patients. In all patients we were able to perform extended esophagectomy with anastomosis located 3 to 7 cm under the pharyngoesophageal junction. Postoperative mortality was 4%. Morbidity due to leakage was 7%; proper drainage enabled spontaneous healing in 5 patients. Fifteen patients had pulmonary complications, none of which fatal, Median actuarial survival was 17 months. Actuarial survival at 24 months is significantly higher for patients in stage I and II (68.4%) than for patients in stage III (23.2%) (p less than 0.01). The Ivor Lewis procedure is a safe surgical approach for the treatment of the esophageal carcinoma that has a high survival rate and allows a good quality of life.

Actuarial Analysis↗

PubMed1991

Delta-like haemolysin produced by Staphylococcus lugdunensis.

Thirty independent clinical isolates of Staphylococcus lugdunensis were tested for expression of haemolysin characteristics of Staphylococcus aureus and for the presence of DNA sequences with homology to S. aureus toxin genes. Twenty-six strains produced a thermostable haemolysin with greatest activity against rabbit erythrocytes. DNA-DNA hybridisation was performed with S. lugdunesis DNA and probed with the alpha, beta, delta and gamma toxin gene probes of S. aureus as well as that for coagulase. Hybridisation was found with the delta probe in 28 strains including 6 which did not express haemolysin. Two strains did not hybridise with any of the probes. These findings suggest that S. lugdunensis strains produce a delta-like toxin which shares homology with the delta toxin of S. aureus.

Bacterial Proteins↗

PubMed1991

Characterization of clinically significant isolates of Staphylococcus epidermidis from patients with cerebrospinal fluid shunt infections.

Biotyping, slime production, antibiograms, extrachromosomal DNA banding and total DNA restriction analysis were used to characterize Staphylococcus epidermidis strains causing cerebrospinal fluid shunt infections in 11 patients. Infections considered to be community acquired and those acquired in the first 2 weeks of hospital admission were due to oxacillin-susceptible isolates. Multiply resistant strains were isolated from patients who were in hospital for more than 1 month before tube implantation. Slime was detected in staphylococci for 54% of cases, but its expression varied. Strains from different patients could be differentiated from one another by the extrachromosomal DNA bandings and total DNA restriction patterns, but isolates from the same patient were usually similar. During the period of external drainage, epidemiological markers were useful in differentiating persistence of infection from contamination or re-infection by a new strain.

Adult↗

PubMed1991

Comparison of different antibiotic regimens for therapy of 32 cases of Q fever endocarditis.

We studied 32 cases of Q fever endocarditis diagnosed in France between January 1985 and December 1989 to evaluate the efficacies of the different regimens of antibiotics used for treatment. Each patient was monitored during the treatment (range, 12 to 60 months), and clinical and biological information was computerized. Various treatments were prescribed, including doxycycline alone (9 cases) or in association with rifampin (4 cases), quinolones (16 cases), or sulfamethoxazole-trimethoprim (1 case). Two patients died before the beginning of the treatment. Nineteen patients had hemodynamic failure and subsequently underwent valve replacement. Nine valve tissue cultures were positive despite previous antibiotic treatment. In terms of their effects on mortality, the difference between doxycycline alone and doxycycline plus quinolones is statistically significant. We conclude that the addition of quinolones to doxycycline is beneficial. On the basis of clinical, serological, and valve tissue culture results, no treatment was able to cure Q fever endocarditis within 2 years, even with a combination of antibiotics. We advise a minimum duration of treatment of 3 years with therapy combining quinolones and doxycycline.

4-Quinolones↗

PubMed1991

Molecular epidemiology of Staphylococcus haemolyticus strains isolated in an Albanian hospital.

A recent outbreak of erythroderma in young children in an Albanian hospital was investigated. The etiology was not established, but Staphylococcus haemolyticus was frequently isolated from the affected children and from staff working in the same unit. Possible relationships among the isolates were investigated by using classical techniques (biotype, antimicrobial susceptibility, and extrachromosomal DNA pattern) and by restriction endonuclease analysis (REA) of total DNA. Control isolates of proven pathogenicity from hospitalized patients in Lyon, France were subjected to the same procedures. Distinct REA patterns were obtained after digestion with two enzymes in 7 of 10 isolates from five affected children. Six distinct patterns were observed in nine isolates from six staff members; two REA patterns from patient isolates and two from staff members were identical, and these were distinguishable by the other markers examined. Only two different REA patterns were found in the pathogenic control isolates despite the use of a third additional enzyme. Again, the isolates with the same REA patterns could be distinguished by their plasmid profile or antimicrobial resistance profile. REA of total DNA used in combination with other markers indicated that the Albanian isolates differed considerably, whereas the French pathogenic isolates showed little variability.

Albania↗

PubMed1991

Comparison and evaluation of nine bibliographic databases concerning adverse drug reactions.

Few evaluations and statistical comparisons of bibliographic databases have been published. As a drug information center, we were particularly interested in databases providing references on adverse drug reactions (ADRs). Ten drugs were randomly chosen from the 2000 files at our center. Nine databases were selected according to the high frequency of references concerning ADRs: eight online systems (MEDLINE, BIOSIS, TOXLINE, Iowa Drug Information System, PASCAL, EMBASE, PHARMLINE, and International Pharmaceutical Abstracts [IPA]), and one Compact Disk Read Only Memory (CD-ROM) system (Core MEDLINE). The total number of references, the number of references from 1987 to 1989, and the number of relevant references from 1987 to 1989 were analyzed using the Friedman two-way ANOVA by ranks. The overlap between databases for only one drug, carboplatin, and the quality:cost ratio were also studied. Considering the total number of references, TOXLINE and EMBASE were significantly superior to IPA, PHARMLINE, PASCAL, and Core MEDLINE. For the period 1987-1989, EMBASE was significantly superior to PASCAL, IPA, PHARMLINE, and Core MEDLINE with regard to total number of references, and significantly superior to PASCAL, Core MEDLINE, and IPA with regard to relevance. MEDLINE, TOXLINE, and EMBASE had the best quality:cost ratio. EMBASE had the slightest overlap of references, with 53 percent of the unique references on carboplatin. This comparative evaluation showed that the ability of bibliographic databases to provide information on ADRs is dependent on both the size and the quality of each database.

Databases, Bibliographic↗

PubMed1991

[Structural characteristics of the human lipoprotein lipase gene].

Lipoprotein lipase plays a major role in the metabolism of circulating triglyceride-rich lipoproteins. In relation with this study, the fundamental results concerning the structure of human LPL gene are first summarized. Sequencing of this gene enabled us to characterize an Alu sequence. Interest of these repetitive sequences is exposed.

Base Sequence↗