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J Bille

Publications and source records attributed to J Bille.

At least 91 records · Page 5Linked to original sources
PubMed1995

Seroprevalence of rubella among women of childbearing age in Switzerland.

A seroepidemiological study was carried out in Switzerland to define the population susceptible to rubella among women of childbearing age. IgG antibodies to rubella virus were determined in 9,046 women giving birth between 1 August 1990 and 30 September 1991 in 23 of 26 Swiss cantons. These sera represented 10-20% of the yearly total number of births in each Swiss canton. Anti-rubella IgG was measured by an automated enzyme-linked fluorescent assay for use with a commercial system (Vidas Rub IgG, bio-Mérieux, France). Before the study population was screened, the commercial system was compared to the traditional hemagglutination-inhibition (HAI) test using 500 consecutive samples from parturient women. The sensitivity was 97.7%, the specificity was 100%, and agreement between the two tests was 97.8%. The discrepancies corresponded to very low titres of antibodies as measured by HAI. The seroprevalence of rubella nationwide in women of childbearing age in Switzerland was 94.3%. The seroprevalence was higher (96.5%) in the 5,677 women of Swiss nationality than in the 3,090 women of a different nationality (90.4%) (p < 0.001). In Swiss women the seroprevalence of rubella did not increase significantly with age and was identical in primiparous and in multiparous women, thus indicating that women of childbearing age are probably not sufficiently immunised.

Adult↗
PubMed1995

Typing Listeria monocytogenes: a comparison of random amplification of polymorphic DNA with 5 other methods.

One hundred Listeria monocytogenes strains were typed by random amplification of polymorphic DNA (RAPD) with three different primers, and the results were compared with those obtained by serotyping, ribotyping, multilocus enzyme electrophoresis, restriction enzyme analysis and phage typing. The RAPD patterns of strains appear to be stable during epidemics even over periods of several years. Reproducibility of the RAPD patterns was good. The discriminatory power of RAPD typing was the best among all the methods tested. RAPD is therefore a very promising tool in the study of listeriosis epidemiology. However, the problems related to the standardization of the technique first have to be resolved before the wide use of RAPD is possible.

Bacterial Typing Techniques↗
PubMed1995

An epidemic of food-borne listeriosis in western Switzerland: description of 57 cases involving adults.

This article describes 57 cases of listeriosis that occurred in adults in western Switzerland during an outbreak associated with the consumption of a soft cheese. Twenty-one percent of the cases were of bacteremia, 40% were of meningitis, and 39% were of meningoencephalitis. Overall, 42% of the patients had an underlying disease and 54% were > 65 years of age. Patients with bacteremia were significantly older than those with meningitis or meningoencephalitis (median ages, 75, 69, and 55 years, respectively). The epidemic strain, defined by phage typing, was isolated in three-quarters of the listerial cases observed during the epidemic period and did not appear to differ significantly from the nonepidemic strains in terms of virulence. The overall mortality associated with the 57 cases was 32%. Among the patients' characteristics, age and type of clinical presentation were independent predictors of death in a multivariate logistic regression model (pseudo-r2 [coefficient of determination], .26; both P values < .05), and a presentation of meningoencephalitis was associated with an increased death risk (odds ratio, 6.5; 95% confidence interval, 1.1-39.5; P < .05). Neurological sequelae developed in 30% of the survivors of CNS listeriosis.

Adult↗
PubMed1995

Medical treatment of staphylococcal infective endocarditis.

Staphylococcal infective endocarditis is a severe event requiring aggressive therapy. Antibiotic regimen depends mainly on (1) the species of Staphylococcus (Staphylococcus aureus versus coagulase-negative staphylococci) and its resistance pattern (resistance to penicillin, to methicillin, to multiple classes of antibiotics); (2) the type of infected valve (native versus prosthetic); (3) the site of infection (left side versus right side endocarditis); (4) some underlying conditions of the host, in particular the presence or not of intravenous drug abuse. Based on in vitro susceptibility results, animal models and clinical trials, the following regimens are currently recommended. For native valve endocarditis, penicillin G 20 million units per day i.v. for 4-6 weeks for penicillin-susceptible strains; a penicillinase-resistant penicillin (oxacillin) 2 g i.v. q 4 h for 4-6 weeks plus an aminoglycoside (gentamicin) 1.0 mg.kg-1 i.v. q 8 h for 1 week, for penicillin-resistant, methicillin-susceptible strains; for methicillin resistant strains, vancomycin 30 mg.kg.day-1 i.v. in 2-4 doses for 4-6 weeks with the addition or not of rifampin 600-900 mg.day-1 orally. For a prosthetic valve endocarditis, a three-drug regimen (oxacillin or vancomycin, plus gentamicin and rifampin) and a longer duration (6 weeks or more) are generally recommended. Shorter (2 weeks) treatment could be delivered to uncomplicated cases of right-sided endocarditis. In view of an increased resistance to classic drugs and suboptimal efficacy of some of them, new therapeutic modalities should be looked at, in particular for endocarditis cases due to methicillin-resistant strains.

Anti-Bacterial Agents↗
PubMed1995

Studies of the detection of Listeria monocytogenes by culture and PCR in cerebrospinal fluid samples from ruminants with listeric encephalitis.

A total of 14 cerebrospinal fluid (CSF) samples from ruminants clinically suspected of suffering from listeric encephalitis were examined by polymerase chain reaction (PCR) for the detection of Listeria monocytogenes (L. m.). Of these samples, 11 were examined bacteriologically. Although the clinical diagnosis was confirmed in eight of 11 ruminants by histological and/or bacteriological examination of the brains, L. m. was only detected in one of the CSF samples using PCR, and in none by culture. The PCR-positive CSF sample was obtained from a sheep which had been treated with antibiotics prior to CSF sampling. From these findings, it was concluded that L. m. only occasionally gains access to the meningoventricular system in the course of listeric encephalitis of ruminants and that a reliable aetiological in vivo diagnosis of listeric encephalitis generally cannot be based on the detection of L. m. in the CSF of affected ruminants.

Animals↗
PubMed1995

Mechanisms of resistance to azole antifungal agents in Candida albicans isolates from AIDS patients involve specific multidrug transporters.

Azole antifungal agents, and especially fluconazole, have been used widely to treat oropharyngeal candidiasis in patients with AIDS. An increasing number of cases of clinical resistance against fluconazole, often correlating with in vitro resistance, have been reported. To investigate the mechanisms of resistance toward azole antifungal agents at the molecular level in clinical C. albicans isolates, we focused on resistance mechanisms related to the cellular target of azoles, i.e., cytochrome P450(14DM) (14DM) and those regulating the transport or accumulation of fluconazole. The analysis of sequential isogenic C. albicans isolates with increasing levels of resistance to fluconazole from five AIDS patients showed that overexpression of the gene encoding 14DM either by gene amplification or by gene deregulation was not the major cause of resistance among these clinical isolates. We found, however, that fluconazole-resistant C. albicans isolates failed to accumulate 3H-labelled fluconazole. This phenomenon was reversed in resistant cells by inhibiting the cellular energy supply with azide, suggesting that resistance could be mediated by energy-requiring efflux pumps such as those described as ATP-binding cassette (ABC) multidrug transporters. In fact, some but not all fluconazole-resistant clinical C. albicans isolates exhibited up to a 10-fold relative increase in mRNA levels for a recently cloned ABC transporter gene called CDR1. In an azole-resistant C. albicans isolate not overexpressing CDR1, the gene for another efflux pump named BENr was massively overexpressed. This gene was cloned from C. albicans for conferring benomyl resistance in Saccharomyces cerevisiae. Therefore, at least the overexpression or the deregulation of these two genes potentially mediates resistance to azoles in C. albicans clinical isolates from AIDS patients with oropharyngeal candidiasis. Involvement of ABC transporters in azole resistance was further evidenced with S. cerevisiae mutants lacking specific multidrug transporters which were rendered hypersusceptible to azole derivatives including fluconazole, itraconazole, and ketoconazole.

AIDS-Related Opportunistic Infections↗
PubMed1995

Division of Listeria monocytogenes serovar 4b strains into two groups by PCR and restriction enzyme analysis.

Altogether, 133 strains of Listeria monocytogenes serovar 4b were investigated. A segment of 2,916 bp containing parts of the two genes inlA and inlB in L. monocytogenes was amplified by the PCR technique. The PCR product obtained was cleaved with the restriction enzyme AluI, and the fragments generated were separated by gel electrophoresis, leading to two distinct groups: PCR-restriction enzyme analysis groups I and II, containing 37 and 96 strains, respectively. The PCR-restriction enzyme analysis method described in this paper could be a useful tool for the subtyping of L. monocytogenes serovar 4b strains.

Animals↗
PubMed1995

Cluster of oral atypical Candida albicans isolates in a group of human immunodeficiency virus-positive drug users.

Twenty-one chlamydospore-forming and germ tube-positive Candida albicans clinical isolates from 15 human immunodeficiency virus (HIV)-positive and 3 HIV-negative patients were examined by two different genetic methods. Multilocus enzyme electrophoresis and hybridization with the C. albicans-specific Ca3 probe showed that such isolates can be split into two genetically distinct groups that can be clearly distinguished. One group mainly contained strains with atypical sugar assimilation patterns and could be distinguished from the other group by the absence of intracellular beta-glucosidase activity. All 13 strains belonging to this group were isolated from the oral cavities of asymptomatic HIV-positive drug users and may be less pathogenic than the eight strains from the other group isolated either from HIV-positive patients with oropharyngeal candidiasis or from HIV-negative patients with invasive candidiasis.

AIDS-Related Opportunistic Infections↗
PubMed1994

[Multicenter evaluation of oral antibiotics: resistance behavior in 5 Swiss centers].

The susceptibility of 2196 fresh clinical isolates to twelve different oral compounds was assessed in five Swiss microbiology institutions during summer 1992. A standardized microdilution system including all other material necessary was employed to assess the antibacterial activity of penicillin G, ampicillin, ampicillin + sulbactam, amoxycillin + clavulanic acid, cefadroxil, cephalexin, cefaclor, cefuroxime, cefetamet, doxycycline, erythromycin and clindamycin. The aminopenicillins (including the beta-lactamase inhibitor combinations) were highly active against the streptococci, in combination with a beta-lactamase inhibitor they covered the majority of the bla+ E. coli and Proteus mirabilis and between 60 to 80% of the Klebsiella spp. and Proteus vulgaris isolates. All the cephalosporins exhibited good activity against the streptococci, they were active against Gram-negative fermentative rods to a varying degree. Cefetamet was also active against many cefaclor and cefuroxime-resistant isolates. A considerable part of the species studied exhibited resistance to doxycycline; the observed resistance of S. agalactia, P. mirabilis, and Morganella morganii agreed with previous findings. Most of the Streptococcus spp. were inhibited by erythromycin and clindamycin. There were only single penicillin resistant S. pneumoniae isolates in the five Swiss centers. Taking account of the above particulars the epidemiology of antimicrobial resistance in Switzerland can be considered satisfactory.

Anti-Bacterial Agents↗
PubMed1994

[Nucleic probes and PCR: application in the diagnosis of bacterial infections].

Probes and amplification systems represent new technologic developments in the domain of clinical microbiology. In spite of their high specificity, simple applicability and high velocity the DNA probes show only little sensitivity especially for the direct detection of microorganisms in clinical samples. This sensitivity lead to the development of DNA-amplification technics. PCR is the most famous of them and the most often used one. Next to the direct detection of microorganisms in clinical samples without culture these technics also allow the direct isolation of bacterial toxins, of genes for resistance to antibiotics as well as a systematic search for pathogens in diseases with unknown cause. Different problems of these methods in daily clinical practice are illustrated by four applications 1. direct detection of mycobacterium tuberculosis complex (M. tbc) in clinical samples, 2. rapid identification of mycobacterial species, 3. their typing for epidemiologic intentions, 4. rapid detection of resistance to antibiotics.

Bacterial Infections↗
PubMed1994

Immunization of BALB/c mice against Helicobacter felis infection with Helicobacter pylori urease.

BACKGROUND/AIMS: Because Helicobacter pylori is a potentially dangerous human pathogen, the protective potential of oral immunization with H. pylori urease and its subunits was evaluated in an animal model. METHODS: Mice were orally immunized with H. pylori sonicate, urease, or recombinant enzymatically inactive urease subunits and then challenged with Helicobacter felis. Control mice were sham-immunized. RESULTS: H. felis colonization was present 5 days after challenge in 9 of 10 sham-immunized, 6 of 9 sonicate-immunized, and 3 of 10 urease-immunized animals (P = 0.031 vs. sham-immunized). Twelve days after challenge, urease B-immunized mice had a weaker colonization than sham-immunized controls, whereas urease A had no effect. After 70 days, most urease A- and urease B-immunized mice had cleared the colonization (10/17: P = 0.0019; 16/20: P = 0.00002 vs. sham-immunized). In urease B-immunized animals, protection was often associated with corpus gastritis. CONCLUSIONS: Oral immunization with H. pylori urease protects mice against H. felis infection. Enzymatically inactive urease A and B subunits contain protective epitopes. It is unclear whether protection depends on the development of a mononuclear inflammatory response in the gastric corpus. Our observations should encourage the development of a human vaccine.

Administration, Oral↗
PubMed1994

Rapid detection and identification of Candida albicans and Torulopsis (Candida) glabrata in clinical specimens by species-specific nested PCR amplification of a cytochrome P-450 lanosterol-alpha-demethylase (L1A1) gene fragment.

PCR of a Candida albicans cytochrome P-450 lanosterol-alpha-demethylase (P450-L1A1) gene segment is a rapid and sensitive method of detection in clinical specimens. This enzyme is a target for azole antifungal action. In order to directly detect and identify the clinically most important species of Candida, we cloned and sequenced 1.3-kbp fragments of the cytochrome P450-L1A1 genes from Torulopsis (Candida) glabrata and from Candida krusei. These segments were compared with the published sequences from C. albicans and Candida tropicalis. Amplimers for gene sequences highly conserved throughout the fungal kingdom were first used; positive PCR results were obtained for C. albicans, T. glabrata, C. krusei, Candida parapsilosis, C. tropicalis, Cryptococcus neoformans, and Trichosporon beigelii DNA extracts. Primers were then selected for a highly variable region of the gene, allowing the species-specific detection from purified DNA of C. albicans, T. glabrata, C. krusei, and C. tropicalis. The assay sensitivity as tested for C. albicans in seeded clinical specimens such as blood, peritoneal fluid, or urine was 10 to 20 cells per 0.1 ml. Compared with results obtained by culture, the sensitivity, specificity, and efficiency of the species-specific nested PCR tested with 80 clinical specimens were 71, 95, and 83% for C. albicans and 100, 97, and 98% for T. glabrata, respectively.

Amino Acid Sequence↗
PubMed1994

Duodenal bacterial overgrowth during treatment in outpatients with omeprazole.

The extent of duodenal bacterial overgrowth during the pronounced inhibition of acid secretion that occurs with omeprazole treatment is unknown. The bacterial content of duodenal juice of patients treated with omeprazole was therefore examined in a controlled prospective study. Duodenal juice was obtained under sterile conditions during diagnostic upper endoscopy. Aspirates were plated quantitatively for anaerobic and aerobic organisms. Twenty five outpatients with peptic ulcer disease were investigated after a 5.7 (0.5) weeks (mean (SEM)) treatment course with 20 mg (nine patients) or 40 mg (16 patients). The control group consisted of 15 outpatients referred for diagnostic endoscopy without prior antisecretory treatment. No patient in the control group had duodenal bacterial overgrowth. In the omeprazole group bacterial overgrowth (> or = 10(5) cfu/ml) was found in 14 (56%) patients (p = 0.0003). The number of bacteria (log10) in duodenal juice in patients treated with omeprazole was distinctly higher (median 5.7; range < 2-8.7) when compared with the control group (median < 2; range < 2-5.0; p = 0.0004). As well as orally derived bacteria, faecal type bacteria were found in seven of 14 and anaerobic bacteria in three of 14 patients. Bacterial overgrowth was similar with the two doses of omeprazole. These results indicate that duodenal bacterial overgrowth of both oral and faecal type bacteria occurs often in ambulatory patients treated with omeprazole. Further studies are needed to determine the clinical significance of these findings, particularly in high risk groups during long term treatment with omeprazole.

Adult↗
PubMed1994

Gastric and duodenal bacterial colonization in HIV-infected patients without gastrointestinal symptoms.

OBJECTIVE: To assess the prevalence of gastric and duodenal bacterial colonization in HIV-infected patients. METHODS: Twenty-three consecutive outpatients at various stages of HIV infection were examined. No patient received antibiotic therapy or antisecretory drugs, and none presented with digestive symptoms. A second group consisted of 39 patients without risk factors for HIV infection referred to the gastroenterology outpatient clinic for suspected peptic ulcer disease. Gastric and duodenal juices were aspirated separately through the endoscope under direct visual control, using a sterilized double-sheathed tube. Specimens were plated quantitatively for both aerobic and anaerobic organisms. Parasitological evaluation was done on duodenal samples. RESULTS: gastric and/or duodenal bacterial colonization was documented in 7/23 (30%) HIV+patients and in 3/39 (8%) patients in the second group (p < 0.05). No parasites were detected. All isolates were oral Gram-positive cocci or bacilli. Mean fasting gastric pH was significantly higher in HIV-infected patients with bacterial colonization than in HIV-infected patients and patients in the second group without bacterial colonization (p < 0.02). There was no correlation between the presence of bacterial colonization and CD4+ cells counts. CONCLUSION: HIV infection may predispose to asymptomatic digestive bacterial colonization. Further studies are needed to assess the role of bacterial colonization in symptomatic patients presenting with diarrhea and/or weight loss.

Adult↗
PubMed1993

Early symptoms and outcome of Listeria monocytogenes rhombencephalitis: 14 adult cases.

Listeria monocytogenes rhombencephalitis has never been studied in a significant group of patients. We describe 14 adult cases who were seen over a 10-year period. A biphasic illness was characteristic: (1) prodromes (5-15 days) with malaise, fatigue, headache, nausea or vomiting, and fever; (2) cranial nerve palsy with facial palsy, diplopia, dysphagia, dysarthria, usually multiple. Meningism and hemi- or tetraparesis were present in 11 patients and cerebellar dysfunction in 9 patients. In 4 cases, CT showed widening of the brain stem with disappearance of the surrounding cisterns. The cerebrospinal fluid was abnormal in all patients in whom this investigation was done (pleocytosis, elevation in protein content). The patients received antibiotic therapy for 2-6 weeks. In the 9 patients who recovered, the neurological dysfunction improved within 2 days to 1 week of the initiation of therapy. There were 5 deaths. At autopsy in 2 cases, there was severe purulent meningitis and rhombencephalitis with predominantly polymorphonuclear cellular infiltration in 1 case, while numerous microabscesses in the midbrain, pons and medulla were observed in the other. We conclude that L. monocytogenes infection should be considered in patients who develop fever and focal neurological signs particularly localized to the brain stem.

Adult↗
PubMed1993

Characterization of Listeria strains from a foodborne listeriosis outbreak by rDNA gene restriction patterns compared to four other typing methods.

The rDNA gene restriction patterns of 134 isolates of Listeria species were determined with pKK3535--a pBR322 derived plasmid containing an Escherichia coli rRNA operon--used as a probe following digestion of chromosomal DNA by EcoRI endonuclease. Nineteen reference and type strains representing all species and serotypes of Listeria showed 17 distinct ribotypes. One hundred and fifteen wild strains of Listeria monocytogenes were ribotyped and the results were compared to those of serotyping, phage typing, multilocus enzyme electrophoresis (MEE) and restriction endonuclease analysis (REA). Ninety-six Listeria monocytogenes serotype 4b wild strains displayed six distinct ribotypes (I-VI), 72% (69/96) of them clustering in two very close rDNA patterns (I and II) of eight and nine bands, respectively. The same 96 strains displayed six REA patterns and eight MEE electrotypes. Among the 96 Listeria monocytogenes 4b isolates, the 34 epidemic strains defined by phage typing and by epidemiological data all belonged to one ribotype (ribotype I) representing 56% of the strains belonging to this ribotype. These same 34 epidemic strains were also grouped by REA and MEE typing in a unique profile (REA-A) and MEE electrotype (ET 1). Twenty-two Listeria monocytogenes strains of serogroup 1/2 analyzed by rDNA typing showed nine distinct ribotypes. For the 96 Listeria monocytogenes 4b strains studied, the discriminatory index was highest for phage typing and for any combination including phage typing. Ribotyping appears to be a well reproducible molecular typing method and could be a useful complement to other typing methods for the epidemiological study of listeriosis.

Bacterial Typing Techniques↗