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11.
Summary The prevalence of ESBL was determined among isolates of Escherichia coli (n = 571) and Klebsiella spp. (n = 196) collected during a 1-week study period in 8 university and 3 large regional laboratories all over the Netherlands. 18 isolates were positive for at least one of the screening tests used, i.e., VITEK-ESBL, E-test ESBL and MIC ratio of ceftazidime/ceftazidime-clavulanic acid, cefotaxime/cefotaxime-clavulanic acid. In 5 of these 18 putative ESBLs no betalactamase production was detectable. A TEM type was found in three E. coli and two Klebsiella spp. An SHV type was present in five Klebsiella spp. In one E. coli and one Klebsiella pneumoniae both enzymes were present. In one Klebsiella oxytoca neither of the two enzymes was present. Using PCR for both ESBL TEM and ESBL SHV, an SHV ESBL was found in one E. coli and four Klebsiella isolates. The mutations at position 238 and 240 were already described. In one E. coli isolate a TEM ESBL was found with three mutations, at position 21, 164 and 265. These mutations were already described in other ESBLs but not in this combination suggesting a new TEM ESBL. The overall prevalence of ESBL producing E. coli and Klebsiella spp. was less than 1% (6 out of 767). Received: December 14, 1998 · Accepted: September 19, 1999  相似文献   
12.
To verify the clinical usefulness of extracellular cyclic nucleotide determination as a tumor marker, plasma cyclic AMP (cAMP) and cyclic GMP (cGMP) levels were measured in 70 normal subjects and 173 acute leukemia patients studied in different stages of their disease. Mean plasma cAMP levels were similar in leukemic and normal subjects, although in 48 patients in the active stage of the disease, first diagnosis, or relapse, the cAMP values were below the normal range, and most of these patients failed to respond to chemotherapy. Plasma cGMP levels were markedly elevated in untreated patients, normalized in all patients who attained complete remission, and increased promptly to pretreatment values in patients who relapsed, suggesting that their determination may be useful to monitor the patients' response to treatment.  相似文献   
13.
To determine the spread of Staphylococcus aureus within and between nursing home (NH) residents in the Euregion Meuse-Rhine, a cross-border region of the Netherlands and Germany, we investigated the prevalence of antibiotic resistance, genetic background and population structure of both methicillin-susceptible S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) isolates. A total of 245 S. aureus isolates were collected from NH residents. Susceptibility testing was performed with microbroth dilution. The genetic background was determined using spa typing, SCCmec typing, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Differences in the prevalence of resistance between the German and Dutch MSSA isolates were observed for the macrolides (15 % vs. 2 %, p?=?0.003), clindamycin (15 % vs. 0 %, p?=?0.003) and ciprofloxacin (34 % vs. 25 %). The macrolide and ciprofloxacin resistance varied between the NHs, while trimethoprim–sulfamethoxazole resistance was low in all residents. The MRSA prevalence was 3.5 % and <1 % among the German and Dutch NH residents, respectively (p?=?0.005). The German MRSAs, isolated in 7 out of 10 NHs, belonged to ST22-MRSA-IV or ST225-MRSA-II. spa clonal complexes (spa-CCs) 015 and 002 were prevalent among the German MSSA isolates and spa-CCs 024 and 1716 were prevalent among the Dutch MSSA isolates. The antibiotic resistance of MSSA and the MRSA prevalence were significantly higher among the German NH residents. The spread of two MRSA clones was observed within and between the German NHs, but not between the Dutch and German NHs. Differences in the prevalence of resistance and the prevalence of MRSA between NHs on both sides of the border warrant the continuation of surveillance at a local level.  相似文献   
14.
15.
The prevalence of atopic diseases, including eczema, allergic rhinoconjunctivitis and asthma, has increased worldwide, predominantly in westernized countries. Recent epidemiological studies and experimental research suggest that microbial stimulation of the immune system influences the development of tolerance to innocuous allergens. The gastrointestinal microbiota composition may be of particular interest, as it provides an early and major source of immune stimulation and seems to be a prerequisite for the development of oral tolerance. In this review the observational studies of the association between the gut microbiota and atopic diseases are discussed. Although most studies indicated an association between the gut microbiota composition and atopic sensitization or symptoms, no specific harmful or protective microbes can be identified yet. Some important methodological issues that have to be considered are the microbiological methods used (traditional culture vs molecular techniques), the timing of examining the gut microbiota, the definition of atopic outcomes, confounding and reverse causation. In conclusion, the microbiota hypothesis in atopic diseases is promising and deserves further attention. To gain more insight into the role of the gut microbiota in the etiology of atopy, large-scale prospective birth cohort studies using molecular methods to study the gut microbiota are needed.  相似文献   
16.
17.
Spa typing/based upon repeat pattern (BURP) sometimes cannot differentiate multilocus sequence typing (MLST) clonal complexes (CCs) within spa-CCs. It has been observed previously that virulence factors, such as collagen adhesin (CNA) and toxic shock syndrome toxin 1 (TSST-1), are associated with certain Staphylococcus aureus lineages. Analysis of methicillin-sensitive and methicillin-resistant S. aureus by spa typing/BURP and detection of CNA and TSST-1 observed an association between CNA and MLST CC1, 12, 22, 30, 45, 51, and 239 and between TSST-1 and MLST CC30. In spa-CC 012, associated with MLST CC7, CC15, and CC30, MLST CC30 could be distinguished from MLST CC7 and CC15 with CNA and TSST-1 as lineage-specific markers. Lineage-specific markers can overcome clustering of nonrelated MLST CCs into 1 spa-CC.  相似文献   
18.
As part of a large, prospective study we investigated the prevalence Helicobacter pylori serum antibodies in children with recurrent abdominal pain (RAP). All patients suffered from recurrent bouts of abdominal pain for at least 6 months and ranged in age from 6 to 12 years. H. pylori antibodies were detected using an enzyme-linked immunosorbent assay. The prevalence of H. pylori antibodies in the RAP group was compared to that of a control group which consisted predominantly of pre-operative children. None of the control group suffered or had suffered from RAP. Antibodies to H. pylori were found in 7 of 82 (8.5%) RAP patients and in 2 of 39 (5.1%) control children. The latter difference is not significant and suggests that RAP is only rarely caused in children by H. pylori infection.  相似文献   
19.
OBJECTIVE: To assess the efficacy of roxithromycin relative to amoxicillin. STUDY DESIGN: We conducted a double-blind randomized controlled trial of oral 500 mg amoxicillin 3 times per day vs oral 300 mg roxithromycin once a day for 10 days. POPULATION: We included 196 adults who had presented to a general practitioner with lower respiratory tract infection (LRTI) and, in the physician's opinion, needed antibiotic treatment. OUTCOMES MEASURED: We measured clinical response after 10 and 28 days, defined in 4 ways: (1) decrease in LRTI symptoms; (2) complete absence of symptoms; (3) decrease in signs; and (4) complete absence of signs. Self-reported response included the decrease in symptoms and the time until resumption of impaired or abandoned daily activities on days 1 through 10, 21, and 27. RESULTS: Clinical cure rates after the completion of antibiotic treatment (10 days) were not significantly different for the 2 groups. After 28 days, the roxithromycin group showed no increase in cure rate as evidenced by the decrease in symptoms, indicating a significantly lower cure rate. However, this difference did not alter physicians' overall conclusion after complete follow-up that 90% of patients, regardless of age, had been effectively treated with either amoxicillin or roxithromycin. CONCLUSIONS: The surplus value of roxithromycin was not confirmed. Amoxicillin remains a reliable first-choice antibiotic in the treatment of LRTI in general practice.  相似文献   
20.
We studied the influences of antimicrobial agents on the colonization of the respiratory tract and infection with Enterococcus faecalis in intensive care unit (ICU) patients receiving mechanical respiration for at least 3 days. In a matched-cohort analysis, patients receiving topical antimicrobial prophylaxis (TAP) of the oropharynx and stomach with antimicrobial agents not treating E. faecalis were compared with patients not receiving TAP. Patients were matched with controls on the basis of their duration in the ICU, their use of systemic antibiotics treating and not treating E. faecalis, the administration of TAP, their APACHE II score, and surgical procedures they had undergone. In all, 276 patients were analyzed. The colonization of the oropharynx and/or trachea by E. faecalis at admission was demonstrated for 43 patients (16%). Twenty patients (9%) acquired tracheal colonization and 91 patients (40%) acquired oropharyngeal colonization with E. faecalis. In the matched-cohort analysis, 43 patients receiving TAP were matched in two controls each. TAP patients more frequently acquired tracheal colonization (15 of 43 versus 2 of 86 patients, P < 0.00001) and infections with E. faecalis (6 of 43 versus 1 of 86 patients, P < 0.01). The use of topical antibiotics and treating E. faecalis increased the risk for colonization and infection with E. faecalis.  相似文献   
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