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41.
B cells bifurcating along ‘type 1’ or ‘type 2’ pathways under the influence of polarizing cytokines can, in turn, influence the direction of an immune response. Here, we compare the capacity of human B cells residing within naïve and memory compartments to participate in type 1 polarizing responses. B‐cell receptor (BCR) engagement provided the main signal for interleukin (IL)‐12Rβ1 expression in the two subsets: this was potentiated by CD154 together with interferon‐γ (IFN‐γ) but inhibited by IL‐12. IL‐12Rβ2 could be induced on a minority of B cells by the same signals, and also by IFN‐γ alone. WSX‐1, a receptor for IL‐27, was expressed in both subsets with no evidence for its regulation by the signals studied. While neither subset was capable of secreting much IL‐12 p70, memory B cells could produce a small amount of IL‐12 p40 on CD40 ligation. Memory B cells also, exclusively, expressed IL‐23 p19 mRNA on BCR triggering. Importantly, products of appropriately stimulated memory – but not naive – B cells were shown to promote the synthesis of IFN‐γ in uncommitted T‐helper cells. The data indicate an equal capacity for naïve and memory B cells to respond within a type 1 polarizing environment. Although poorly equipped for initiating type 1 responses, B cells – by virtue of the memory subset – reveal a capacity for their maintenance and amplification following T‐dependent signalling.  相似文献   
42.
Three cases of Clostridium difficile-associated disease in children were detected within a short time interval. Intensive therapy was required in 2 cases with colectomy in one of them. One of the severe cases was community-acquired. Two patients had underlying diseases (Hirschprung disease, Down syndrome) and also tested positive for enteric viruses (rotavirus, calicivirus).  相似文献   
43.

Background

The aim of this study was to examine whether 31P NMR can efficiently detect X-ray radiation induced changes of energy metabolism in mice. Exposure to ionizing radiation causes changes in energy supply that are associated with the tissue damage because of oxidative stress and uncoupled oxidative phosphorylation. This has as a consequence decreased phosphocreatine to adenosine triphosphate ratio (Pcr/ATP) as well as increased creatine kinase (CK) and liver enzymes (transaminases AST and ALT) levels in serum.

Materials and methods

In this study, experimental mice that received 7 Gy of X-ray radiation and a control group were studied by 31P NMR spectroscopy and biochemically by measuring CK and liver enzyme levels in plasma. Mice (irradiated and control) were measured at regular time intervals for the next three weeks after the exposure to radiation.

Results

A significant change in the Pcr/ATP ratio, determined from corresponding peaks of 31P NMR spectra, was observed in the 7 Gy group 2 days or more after the irradiation, while no significant change in the Pcr/ATP ratio, was observed in the control group. This result was supported by parallel measurements of CK levels that were highly increased immediately after the irradiation which correlates with the observed decrease of the Pcr/ATP ratio and with it associated drop of muscle energy supply.

Conclusions

The 31P NMR measurements of the Pcr/ATP ratio can in principle serve as an instantaneous and noninvasive index for assessment of the received dose of irradiation.  相似文献   
44.
OBJECTIVE: Genetic factors play an important role in the development of asbestosis. The aim of this study was to investigate whether genetic polymorphisms of glutathione S-transferase (GST) P1 represent a risk factor for this disease. METHODS: The study population included 262 workers with asbestosis and 265 matched controls. Information on cumulative asbestos exposure was available. A real-time PCR based on the 5' nuclease assay was designed for the analysis of GSTP1 Ile105Val and Ala114Val polymorphisms. RESULTS: Asbestosis was associated with GSTP1 genotype coding for an enzyme with high conjugation capacity versus genotypes resulting in intermediate and low enzyme activity (odds ratio = 1.49, confidence interval = 1.06-2.10). CONCLUSIONS: The key finding of the study was that GSTP1 genotype coding for an enzyme with high conjugation capacity significantly increases the risk of developing asbestosis.  相似文献   
45.
Muscular hypertrophy secondary to denervation is very rare, but well-documented phenomena in adults. This is the first report of a child with neurogenic unilateral hypertrophy due to S1 radiculopathy. A 12-year-old girl presented with left calf hypertrophy and negative history of low back pain or trauma. The serum creatinine kinase level and inflammatory markers were normal. Magnetic resonance imaging showed muscle hypertrophy of the left gastrocnemius and revealed a protruded lumbar disc at the L5-S1 level. The protruded disc abuts the S1 root on the left side. Electromyography showed mild left S1 radiculopathy. Passive stretching and work load might clarify the origin of neurogenic hypertrophy but there is still a need for further evidence. Clinical, laboratory, magnetic resonance imaging and electromyography findings showed that S1 radiculopathy could be a cause of unilateral calf swelling in youth even in the absence of a history of back or leg pain.  相似文献   
46.

Objective

To assess the efficacy of orally administered capsules containing the probiotics Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14 (Lactogyn, JGL, Rijeka, Croatia) compared to placebo in otherwise healthy women diagnosed with bacterial vaginosis.

Study design

Randomized, double-blind, multicentric, placebo-controlled trial, including a total of 544 subjects. Included were women older than 18 years of age, diagnosed with vaginal infection. Subjects received either probiotic (395 subjects or 72.6%) or identical-looking placebo capsules (149 subjects or 27.4%,) per day over a period of 6 weeks. Six and 12 weeks after the beginning of the study, subjects underwent two additional gynecological examinations and their vaginal swabs were evaluated by a clinical cytologist.

Results

Mean follow-up period after the baseline visit was 44 days. After this period, restitution to balanced vaginal microbiota was reported in 40 subjects (26.9%) in the placebo group, compared to 243 subjects (61.5%) in the probiotic group. Differences between groups were statistically significant at p < 0.001. After the additional 6 weeks of follow up, normal vaginal microbiota were still present in more than half (51.1%) of subjects in the probiotic group, but only in around one-fifth (20.8%) of subjects who were taking placebo (p < 0.001).

Conclusion

Oral probiotics could be an alternative, side effect-free treatment for one of the most common indications in gynecology, combining the good aspects of both metronidazole and vaginal capsules.  相似文献   
47.
48.
IntroductionAimed at preparing the basis for planning evidence-based public health measures for preservation/ improvement of nurses’ work ability (WA), the objective was to assess the relationship between WA and sense of coherence (SOC).MethodsA cross-sectional study was conducted in 2018 among 713 nurses in Croatia. The association between poor WA index (PWAI) and SOC score (SOCS), adjusted for possible confounders, was determined by binary logistic regression analysis.ResultsThe results of univariate logistic regression analysis showed a statistically significant negative association between SOCS and PWAI (OR=0.977, 95% CI 0.968 – 0.986, p<0.001). The results of multivariate logistic analysis showed an even stronger statistically significant negative association between SOCS and PWAI (OR=0.966, 95% CI 0.954 – 0.977, p<0.001) when adjusted for confounders.ConclusionsThe present study suggested SOC as an important health promoting resource of nurses which might offer protection regarding work-related stress. Weak SOC could be an important explanatory factor of poor WA. Accordingly, improving SOC by implementing health promotion measures in nurses’ workplace could be an important way to increase the WA among nurses.  相似文献   
49.
The primary objective in the study is determination of efficacy of probiotic preparation as a supportive therapy in eradication of Helicobacter pylori.The study was multicenter, prospective, randomized, placebo controlled, and double-blind. The subjects first filled out a specially designed questionnaire to assess the severity of the 10 symptoms, which can be related to eradication therapy to be monitored during the trial. Each subject then received 28 capsules of probiotic preparation or matching placebo capsules, which they were supposed to take over the following 14 days, twice a day, at least 2 hours prior to or after the antibiotic therapy administration.A total of 804 patients were enrolled in the trial, of which 650 (80.85%) were included in the analysis. The results show a significantly larger share of cured subjects in the probiotic arm versus the placebo arm (87.38% vs 72.55%; P < 0.001). Additionally, presence and intensity of epigastric pain, bloating, flatulence, taste disturbance, loss of appetite, nausea, vomiting, heartburn, rash, and diarrhea were monitored over the study period. At 15 days postinclusion, probiotic treatment was found superior to placebo in 7 of 10 mentioned symptoms. Average intensity for symptoms potentially related to antibiotic therapy was significantly higher in the placebo group, 0.76 vs 0.55 (P < 0.001).Adding probiotics to the standard triple therapy for H pylori eradication significantly contributes to treatment efficacy and distinctly decreases the adverse effects of therapy and the symptoms of the underlying disease.  相似文献   
50.
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