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21.
Probiotics and Antimicrobial Proteins - Probiotic-rich foods are consumed without much restriction. We report here, a case of septic shock caused by yogurt derived Lactobacillus species in a...  相似文献   
22.
We investigated how differences in circadian rhythm type affect the health of workers engaged in shift work. Employees, who were newly hired in a steel company between 2007 and 2011, received the Morningness–Eveningness Questionnaire (MEQ) survey. The target participants were 153 male shift workers who were not being treated with any antihyperlipidemic drugs and underwent periodic physical examinations including blood tests at least twice. According to the score of the MEQ at the time of joining the company, we classified the subjects into five types. Longitudinal changes in serum lipid level were estimated among the circadian rhythm types adjusted for age, BMI, and other covariates using a linear mixed model. The regression coefficient of total cholesterol level in the “definitely and moderately morning” group was ?17.83 (95% confidence interval (CI): ?33.42 to ?2.23), and in the “intermediate ‘group’ was ?16.84 [95% CI: ?30.40 to ?3.28], compared to the moderate evening type.” The total cholesterol level was higher in the moderately evening type than in any of the other groups. Between the Morningness–Eveningness (ME) type and Low-density lipoprotein (LDL) cholesterol levels, compared with the “moderately evening type” group, the regression coefficient in the “intermediate type” group was ?16.08 (95% CI: ?28.79 to ?3.37), and in the “definitely and moderately morning type” group was ?17.50 [95% CI: ?32.11 to ?2.88]. The “moderately evening type” group had a higher LDL cholesterol level than any of the other groups. Evening-type circadian rhythm type shift workers are more prone to elevated serum lipid levels.  相似文献   
23.
Plant Ecology - Volatile compounds from leaf litter of invasive alien Ageratina adenophora are known to inhibit growth of native species in sub-tropical Asia, but there is not...  相似文献   
24.
Previous studies indicate that the O-helix of Thermus aquaticus (Taq) DNA polymerase I (pol I) plays an important role in the replication fidelity of the enzyme. This study examines the role of Thr-664, which lies in the middle of the O-helix of Taq pol I. A mutant of Taq Pol I with a proline substitution of Thr-664 (T664P) exhibits much lower replication fidelity than the wild type enzyme in a forward mutation assay. T664P produces base substitution, single-base deletion, and single-base insertion errors at 20-, 5, and 50-fold higher rates than wild type, respectively. In specific activity and steady-state kinetic experiments, T664P was catalytically robust for insertion of correct nucleotides. In contrast, it incorporated incorrect nucleotides 6.1- to 10-fold more efficiently than wild type at a template dC. Mismatched primer termini were extended by T664P 4.2- to 9.5-fold more efficiently than wild type. These data imply that the O-helix with a proline at position 664 functions like wild type Taq pol I for correct nucleotide incorporations, but bends and enlarges the catalytic pocket of the enzyme and increases the rate of nucleotide misincorporation.  相似文献   
25.
B. Ludvik et al., have recently shown the effect of Caiapo (Ipomoea batatas L.) on reducing fasting blood glucose and insulin resistance in type-2 diabetic patients. It, however, was required 2-4 weeks after the single administration of Caiapo. The present study aimed to determine if the combination therapy of Caiapo with a mulberry leaf powder, which inhibits alpha-glucosidase, or with a loquat leaf extract, which shows an insulin-like effect, could make it possible to enhance the antidiabetic activities of Caiapo, and to shorten the time necessary for the inhibition of increasing blood glucose levels. A mixture of the pulverized tuber of Caiapo (357 mg/kg) and the mulberry leaf powder (143 mg/kg), or a mixture of the pulverized skin of Caiapo (194 mg/kg) and the powdered loquat leaf extract (6 mg/kg) was orally administered to 6 weeks-old male KK-Ay mice for 28 days and the glucose loading test was conducted every 7 days. In the glucose loading test after one week feeding, a reduction in blood glucose concentration after 60 minutes of the administration of glucose was observed in both mixture groups against the control group (p < 0.05) in the case of Caiapo only, similar delayed effects were seen in 2-3 weeks after feeding.  相似文献   
26.
Oligodendroglial lineage cells (OLC) vary in susceptibility to both necrosis and apoptosis depending on their developmental stages, which might be regulated by differential expression of Bcl-2-related genes. As an initial step to test this hypothesis, we examined the expression of 19 Bcl-2-related genes in purified cultures of rat oligodendroglial progenitors, immature and mature oligodendrocytes. All 'multidomain' anti-apoptotic members (Bcl-x, Bcl-2, Mcl-1, Bcl-w and Bcl2l10/Diva/Boo) except Bcl2a1/A1 are expressed in OLC. Semiquantitative and real-time RT-PCR revealed that Bcl-xL and Mcl-1 mRNAs are the dominant anti-apoptotic members and increase four- and twofold, respectively, with maturation. Bcl-2 mRNA is less abundant than Bcl-xL mRNA in progenitors and falls an additional 10-fold during differentiation. Bcl-w mRNA also increases, with significant changes in its splicing pattern, as OLC mature. Transfection studies demonstrated that Bcl-xL overexpression protects against kainate-induced excitotoxicity, whereas Bcl-2 overexpression does not. As for 'multidomain' pro-apoptotic members (Bax, Bad and Bok/Mtd), Bax and Bak are highly expressed throughout differentiation. Among 'BH3 domain-only' members examined (Bim, Biklk, DP5/Hrk, Bad, Bid, Noxa, Puma/Bbc3, Bmf, BNip3 and BNip3L), BNip3 and Bmf mRNAs increase markedly during differentiation. These results provide basic information to guide further studies on the roles for Bcl-2-related family proteins in OLC death.  相似文献   
27.
The (6-4) photoproduct formed by ultraviolet light is known as an alkali-labile DNA lesion. Strand breaks occur at (6-4) photoproducts when UV-irradiated DNA is treated with hot alkali. We have analyzed the degradation reaction of this photoproduct under alkaline conditions using synthetic oligonucleotides. A tetramer, d(GT(6-4)TC), was prepared, and its degradation in 50 mm KOH at 60 degrees C was monitored by high performance liquid chromatography. A single peak with a UV absorption spectrum similar to that of the starting material was detected after the reaction, and this compound was regarded as an intermediate before the strand break. The formation of this intermediate was compared with intermediates from the degradation of other alkali-labile lesions such as the abasic site, thymine glycol, and 5,6-dihydrothymine. The results strongly suggested that the first step of the alkali degradation of the (6-4) photoproduct was the hydrolysis between the N3 and C4 positions of the 5'-pyrimidine component. Analyses by NMR spectroscopy and mass spectrometry supported the chemical structure of this product. Assays of the complex formation with XPC.HR23B and the translesion synthesis by DNA polymerase eta revealed that the biochemical properties are indistinguishable between the intact and hydrolyzed photoproducts.  相似文献   
28.
29.
Supplement of 1% lithocholic acid (LCA) in the diet for 5-9 days resulted in elevated levels of the marker for liver damage aspartate aminotransferase and alkaline phosphatase activities in both farnesoid X receptor (FXR)-null and wild-type female mice. The levels were clearly higher in wild-type mice than in FXR-null mice, despite the diminished expression of a bile salt export pump in the latter. Consistent with liver toxicity marker activities, serum and liver levels of bile acids, particularly LCA and taurolithocholic acid, were clearly higher in wild-type mice than in FXR-null mice after 1% LCA supplement. Marked increases in hepatic sulfating activity for LCA (5.5-fold) and hydroxysteroid sulfotransferase (St) 2a (5.8-fold) were detected in liver of FXR-null mice. A 7.4-fold higher 3alpha-sulfated bile acid concentration was observed in bile of FXR-null mice fed an LCA diet compared with that of wild-type mice. Liver St2a content was inversely correlated with levels of alkaline phosphatase. In contrast, microsomal LCA 6beta-hydroxylation was not increased and was in fact lower in FXR-null mice compared in wild-type mice. Clear decreases in mRNA encoding sodium taurocholate cotransporting polypeptide, organic anion transporting polypeptide 1, and liver-specific organic anion transporter-1 function in bile acid import were detected in LCA-fed mice. These transporter levels are higher in FXR-null mice than wild-type mice after 1% LCA supplement. No obvious changes were detected in the Mrp2, Mrp3, and Mrp4 mRNAs. These results indicate hydroxysteroid sulfotransferase-mediated LCA sulfation as a major pathway for protection against LCA-induced liver damage. Furthermore, Northern blot analysis using FXR-null, pregnane X receptor-null, and FXR-pregnane X receptor double-null mice suggests a repressive role of these nuclear receptors on basal St2a expression.  相似文献   
30.
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