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151.
152.
Isolation of Borna disease virus from human brain tissue   总被引:7,自引:0,他引:7       下载免费PDF全文
Serological and molecular epidemiological studies indicate that Borna disease virus (BDV) can infect humans and is possibly associated with certain neuropsychiatric disorders. We examined brain tissue collected at autopsy from four schizophrenic patients and two healthy controls for the presence of BDV markers in 12 different brain regions. BDV RNA and antigen was detected in four brain regions of a BDV-seropositive schizophrenic patient (P2) with a very recent (2 years) onset of disease. BDV markers exhibited a regionally localized distribution. BDV RNA was found in newborn Mongolian gerbils intracranially inoculated with homogenates from BDV-positive brain regions of P2. Human oligodendroglia (OL) cells inoculated with brain homogenates from BDV-positive gerbils allowed propagation and isolation of BDVHuP2br, a human brain-derived BDV. Virus isolation was also possible by transfection of Vero cells with ribonucleoprotein complexes prepared from BDV-positive human and gerbil brain tissues. BDVHuP2br was genetically closely related to but distinct from previously reported human- and animal-derived BDV sequences.  相似文献   
153.
Damping-off of tomato caused by Rhizoctonia solani was controlled in a pot test using the biological agent, Bacillus subtilis RB14-C, and the chemical pesticide, Flutolanil. The co-utilization of B. subtilis RB14-C, and Flutolanil decreased the amount of Flutolanil used from 375 g/pot when Flutolanil was used alone to 94 g/pot, while exerting the same effect of reducing disease occurrence.  相似文献   
154.
155.
Secondary bile acid-producing bacteria were isolated from human feces to improve our appreciation of the functional diversity and redundancy of the intestinal microbiota. In total, 619 bacterial colonies were isolated using a nutrient-poor agar medium and the level of secondary bile acid formation was examined in each by a liquid culture, followed by thin-layer chromatography. Of five strains analyzed by 16S rRNA gene sequencing and biochemical testing, one was identified as Bacteroides intestinalis AM-1, which was not previously recognized as a secondary bile-acid producer. GC-MS revealed that B. intestinalis AM-1 converts cholic acid (CA) and chenodeoxycholic acid into their 7-oxo derivatives, 7-oxo-deoxycholic acid (7-oxo-DCA) and 7-oxo-lithocholic acid, respectively. Thus, B. intestinalis AM-1 possesses 7α-hydroxysteroid dehydrogenase (7α-HSDH) activity. In liquid culture, B. intestinalis AM-1 showed a relatively higher productivity of 7-oxo-DCA than Escherichia coli HB101 and Bacteroides fragilis JCM11019T, which are known to possess 7α-HSDH activity. The level of 7α-HSDH activity was higher in B. intestinalis AM-1 than in the other two strains under the conditions tested. The 7α-HSDH activity in each of the three strains is not induced by CA; instead, it is regulated in a growth phase-dependent manner.  相似文献   
156.
The purpose of this study was to attempt to find related variables of the canine genome with behavioural traits of dogs maintained and tested in a guide dog facility which provided a relatively uniform environment. The study involved 81 Labrador Retrievers that were being trained as guide dogs. Each dog was taken on walk-out sessions in which the trainer weekly recorded observations that were related to behavioural traits. The records were subjected to key-word analysis of 14 behaviour-related words. A factor analysis on the appearance rate of the 14 key words or phrases resulted in the extraction of six factors that accounted for 67.4% of the variance. Factor 1, referred to as aggressiveness, was significantly related to the success or failure of the dog in qualifying as a guide dog, and was also related to the variable of litter identification. Factor 2, referred to as distraction, was related to the variable of trainer. Factor 3, activity level, was related to the variable of sex, and was significantly related to the polymorphisms of c.471T>C in the solute carrier family 1 ( neuronal/epithelial high affinity glutamate transporter ) member 2 gene and c.216G>A in the catechol-O-methyltransferase gene. The involvement of polymorphisms c.471T>C and c.216G>A in behavioural patterns related to activity level is similar to comparable genetic studies in other mammalian species. These results contribute to a greater understanding of the role of these genes in behaviour.  相似文献   
157.

Objective

We aimed to examine factors associated with untreated diabetes in a nationally representative sample of the Japanese population.

Research Design and Methods

We pooled data from the Japanese National Health and Nutrition Survey from 2005 to 2009 (n = 20,496). Individuals aged 20 years and older were included in the analysis. We classified participants as having diabetes if they had HbA1c levels ≥6.5% (≥48 mmol/mol). People with diabetes who self-reported that they were not currently receiving diabetic treatment were considered to be untreated. We conducted a multinomial logistic regression analysis to determine factors associated with untreated diabetes relative to non-diabetic individuals.

Results

Of 20,496 participants who were included in the analysis, untreated diabetes was present in 748 (3.6%). Among participants with untreated diabetes, 48.3% were previously diagnosed with diabetes, and 46.5% had HbA1c levels ≥7.0% (≥53 mmol/mol). Participants with untreated diabetes were significantly more likely than non-diabetic participants to be male, older, and currently smoking, have lower HDL cholesterol levels and higher BMI, non-HDL cholesterol levels, and systolic blood pressure.

Conclusions

A substantial proportion of people in Japan with untreated diabetes have poor glycemic control. Targeting relevant factors for untreated diabetes in screening programs may be effective to enhance the treatment and control of diabetes.  相似文献   
158.
159.
In this study, the equivalence of the kinetic mechanisms of the formation of urea-induced kinetic folding intermediates and non-native equilibrium states was investigated in apomyoglobin. Despite having similar structural properties, equilibrium and kinetic intermediates accumulate under different conditions and via different mechanisms, and it remains unknown whether their formation involves shared or distinct kinetic mechanisms. To investigate the potential mechanisms of formation, the refolding and unfolding kinetics of horse apomyoglobin were measured by continuous- and stopped-flow fluorescence over a time range from approximately 100 μs to 10 s, along with equilibrium unfolding transitions, as a function of urea concentration at pH 6.0 and 8°C. The formation of a kinetic intermediate was observed over a wider range of urea concentrations (0–2.2 M) than the formation of the native state (0–1.6 M). Additionally, the kinetic intermediate remained populated as the predominant equilibrium state under conditions where the native and unfolded states were unstable (at ~0.7–2 M urea). A continuous shift from the kinetic to the equilibrium intermediate was observed as urea concentrations increased from 0 M to ~2 M, which indicates that these states share a common kinetic folding mechanism. This finding supports the conclusion that these intermediates are equivalent. Our results in turn suggest that the regions of the protein that resist denaturant perturbations form during the earlier stages of folding, which further supports the structural equivalence of transient and equilibrium intermediates. An additional folding intermediate accumulated within ~140 μs of refolding and an unfolding intermediate accumulated in <1 ms of unfolding. Finally, by using quantitative modeling, we showed that a five-state sequential scheme appropriately describes the folding mechanism of horse apomyoglobin.  相似文献   
160.
Gravity change affects many immunological systems. We investigated the effects of hypergravity (2G) on murine thymic cells. Exposure of mice to 2G for three days reduced the frequency of CD4+CD8+ thymocytes (DP) and mature medullary thymic epithelial cells (mTECs), accompanied by an increment of keratin-5 and keratin-8 double-positive (K5+K8+) TECs that reportedly contain TEC progenitors. Whereas the reduction of DP was recovered by a 14-day exposure to 2G, the reduction of mature mTECs and the increment of K5+K8+ TEC persisted. Interestingly, a surgical lesion of the inner ear’s vestibular apparatus inhibited these hypergravity effects. Quantitative PCR analysis revealed that the gene expression of Aire and RANK that are critical for mTEC function and development were up-regulated by the 3-day exposure and subsequently down-regulated by the 14-day exposure to 2G. Unexpectedly, this dynamic change in mTEC gene expression was independent of the vestibular apparatus. Overall, data suggest that 2G causes a temporary reduction of DP and a persistent reduction of mature mTECs in a vestibular system-dependent manner, and also dysregulates mTEC gene expression without involving the vestibular system. These data might provide insight on the impact of gravity change on thymic functions during spaceflight and living.  相似文献   
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