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Cellular localization of the Yes-associated protein (YAP) is dependent on large tumor suppressor (LATS) kinase activity and initiates lineage specification in the preimplantation embryo. We temporally reduced LATS activity to disrupt this early event, allowing its reactivation at later stages. This interference resulted in an irreversible lineage misspecification and aberrant polarization of the inner cell mass (ICM). Complementation experiments revealed that neither epiblast nor primitive endoderm can be established from these ICMs. We therefore conclude that precisely timed YAP localization in early morulae is essential to prevent trophectoderm marker expression in, and lineage specification of, the ICM.  相似文献   
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Manufacture of lead-containing products has long been associated with various health risks. To get an insight into the related genotoxic risks, we conducted a biomonitoring study in 50 exposed workers and 48 matched controls using a battery of endpoints that sensitively detect the extent of genome instability in peripheral blood lymphocytes. The levels of primary DNA damage were estimated with the alkaline comet assay, while cytogenetic abnormalities were determined with the cytokinesis-block micronucleus (CBMN) cytome assay. Additionally, CBMN slides of 20 exposed and 16 control participants were subjected to fluorescence in situ hybridisation (FISH), coupled with pancentromeric probes to establish the incidence of centromere-positive micronuclei, nuclear buds, and nucleoplasmic bridges. Blood lead levels (B-Pb) were measured with atomic absorption spectrometry. To further characterise cumulative effects of occupational exposure, we measured erythrocyte protoporphyrin (EP) concentrations and delta-aminolevulinic acid dehydratase (ALAD) activity in blood. We also assessed the influence of serum folate (S-folate) and vitamin B12 (S-B12) on genome stability. Compared to controls, occupationally exposed workers demonstrated significantly higher B-Pb (298.36±162.07 vs 41.58±23.02), MN frequency (18.71±11.06 vs 8.98±7.50), centromere positive MN (C+ MN) (8.15±1.8 vs 3.69±0.47), and centromere negative MN (C- MN) (14.55±1.80 vs 4.56±0.89). Exposed women had significantly higher comet tail intensity (TI) and length (TL) than control women. Furthermore, workers showed a positive correlation between age and nuclear buds and MN, between MN and years of exposure, and between S-B12 levels and TI and ALAD activity, while a negative correlation was found between TI and B-Pb. These findings suggest that occupational settings in the manufacture of lead-containing products pose significant genotoxic risks, which calls for developing more effective work safety programmes, including periodical monitoring of B-Pb and genetic endpoints.Key words: blood lead, genetic endpoints, genome damage, human lymphocytes, MN-FISH  相似文献   
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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   
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Madelung syndrome (benign lipomatosis): clinical course and treatment.   总被引:2,自引:0,他引:2  
Madelung syndrome is a rare disease found predominantly in the Mediterranean area. It has a distinctive clinical appearance. Staged surgery is the treatment of choice, which produces substantial improvement in both functional and aesthetic appearance. Recurrences usually occur when it is impossible to resect the disease completely.  相似文献   
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Purpose  

The aim of the study was to evaluate exposure to moulds and house dust mite Dermatophagoides pteronyssinus in poultry farms, and related health effects in poultry workers (PW).  相似文献   
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