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31.
We identified a new subgroup of koala retrovirus (KoRV), named KoRV-J, which utilizes thiamine transport protein 1 as a receptor instead of the Pit-1 receptor used by KoRV (KoRV-A). By subgroup-specific PCR, KoRV-J and KoRV-A were detected in 67.5 and 100% of koalas originating from koalas from northern Australia, respectively. Altogether, our results indicate that the invasion of the koala population by KoRV-J may have occurred more recently than invasion by KoRV-A.  相似文献   
32.
When a solution of soybean acid-precipitated or 11S protein was frozen and stored at ?1 to ?5°C, the protein became partially insoluble after thawing. Ultracentrifugation and disc-electrophoresis of freeze-stored 11S protein solution after removing insoluble components revealed that new components which may be aggregates or associates of the 11S component were formed. When concentrated and stored at 5°C, disc-electrophoresis of 11S component showed that associates were formed. Mercaptoethanol could dissolve the insoluble protein and also convert the associates to the original 11S component. NEM–11S was not insolubilized by frozen storage at ?5°C or storage at 5°C after being concentrated. From these facts it can be concluded that denaturation of soybean protein by freezing may be caused by intermolecular reactions through S-S bonds as a result of concentration by freezing. This may suggest a mechanism of the formation of sponge-like texture in kori-tofu which is made by frozen storage of soybean curd for 15 to 20 days at ?1 to ?3°C.  相似文献   
33.
In the tricarboxylic acid (TCA) cycle, NADP+-specific isocitrate dehydrogenase (NADP+-ICDH) catalyzes oxidative decarboxylation of isocitric acid to form α-ketoglutaric acid with NADP+ as a cofactor. We constructed an NADP+-ICDH gene (icdA)-overexpressing strain (OPI-1) using Aspergillus niger WU-2223L as a host and examined the effects of increase in NADP+-ICDH activity on citric acid production. Under citric acid-producing conditions with glucose as the carbon source, the amounts of citric acid produced and glucose consumed by OPI-1 for the 12-d cultivation period decreased by 18.7 and 10.5%, respectively, compared with those by WU-2223L. These results indicate that the amount of citric acid produced by A. niger can be altered with the NADP+-ICDH activity. Therefore, NADP+-ICDH is an important regulator of citric acid production in the TCA cycle of A. niger. Thus, we propose that the icdA gene is a potentially valuable tool for modulating citric acid production by metabolic engineering.  相似文献   
34.
35.
The Roma people, living throughout Europe and West Asia, are a diverse population linked by the Romani language and culture. Previous linguistic and genetic studies have suggested that the Roma migrated into Europe from South Asia about 1,000–1,500 years ago. Genetic inferences about Roma history have mostly focused on the Y chromosome and mitochondrial DNA. To explore what additional information can be learned from genome-wide data, we analyzed data from six Roma groups that we genotyped at hundreds of thousands of single nucleotide polymorphisms (SNPs). We estimate that the Roma harbor about 80% West Eurasian ancestry–derived from a combination of European and South Asian sources–and that the date of admixture of South Asian and European ancestry was about 850 years before present. We provide evidence for Eastern Europe being a major source of European ancestry, and North-west India being a major source of the South Asian ancestry in the Roma. By computing allele sharing as a measure of linkage disequilibrium, we estimate that the migration of Roma out of the Indian subcontinent was accompanied by a severe founder event, which appears to have been followed by a major demographic expansion after the arrival in Europe.  相似文献   
36.

Background

Despite the high prevalence of gastroesophageal reflux disease (GERD), its risk factors are still a subject of controversy. This is probably due to inadequate distinction between reflux esophagitis (RE) and non-erosive reflux disease (NERD), and is also due to inadequate evaluation of adjacent stomach. Our aim is therefore to define background factors of RE and NERD independently, based on the evaluation of Helicobacter pylori infection and gastric atrophy.

Methods

We analyzed 10,837 healthy Japanese subjects (6,332 men and 4,505 women, aged 20–87 years) who underwent upper gastrointestinal endoscopy. RE was diagnosed as the presence of mucosal break, and NERD was diagnosed as the presence of heartburn and/or acid regurgitation in RE-free subjects. Using GERD-free subjects as control, background factors for RE and NERD were separately analyzed using logistic regression to evaluate standardized coefficients (SC), odds ratio (OR), and p-value.

Results

Of the 10,837 study subjects, we diagnosed 733 (6.8%) as RE and 1,722 (15.9%) as NERD. For RE, male gender (SC = 0.557, OR = 1.75), HP non-infection (SC = 0.552, OR = 1.74), higher pepsinogen I/II ratio (SC = 0.496, OR = 1.64), higher BMI (SC = 0.464, OR = 1.60), alcohol drinking (SC = 0.161, OR = 1.17), older age (SC = 0.148, OR = 1.16), and smoking (SC = 0.129, OR = 1.14) are positively correlated factors. For NERD, HP infection (SC = 0.106, OR = 1.11), female gender (SC = 0.099, OR = 1.10), younger age (SC = 0.099, OR = 1.10), higher pepsinogen I/II ratio (SC = 0.099, OR = 1.10), smoking (SC = 0.080, OR = 1.08), higher BMI (SC = 0.078, OR = 1.08), and alcohol drinking (SC = 0.076, OR = 1.08) are positively correlated factors. Prevalence of RE in subjects with chronic HP infection and successful HP eradication denotes significant difference (2.3% and 8.8%; p<0.0001), whereas that of NERD shows no difference (18.2% and 20.8%; p = 0.064).

Conclusions

Significantly associated factors of NERD are considerably different from those of RE, indicating that these two disorders are pathophysiologically distinct. Eradication of Helicobacter pylori may have disadvantageous effects on RE but not on NERD.  相似文献   
37.

Background

Carotid sinus syndrome (CSS) can cause prodromal symptoms of syncope such as dizziness and nausea. Patients with end-stage cancer lose self-efficacy associated with reduced activities of daily life (ADL). Herein, we report a case of end-stage cancer in which self-efficacy was enhanced as the patient gained self-control of prodromal symptoms of syncope.

Case presentation

A 70-year-old patient with end-stage esophageal cancer and enlarged supraclavicular lymph nodes developed CSS. The CSS was a mixed type with both bradycardia and decreased blood pressure, accompanied by prodromal symptoms prior to syncope episodes. The patient incidentally discovered that he could decrease the duration of symptoms by contracting the muscles in his hands and legs. By applying this coping method at the onset of prodromal symptoms, he was also able to reduce the severity and duration of symptoms, which resulted in enhanced self-efficacy. As a result, the frequency of prodromal symptoms also decreased even though ADL improved.

Conclusion

This patient was diagnosed with vasoinhibitory-predominant mixed-type CSS. The coping method the patient developed seemed to avoid the onset of abrupt blood pressure decrease via peripheral vascular constriction action. Achievement of adequate coping such as self-control of prodromal symptoms enabled our patient to improve his self-efficacy even at the end stages of cancer. This case of enhanced self-efficacy could possibly illustrate a placebo effect for prevention of recurrence.
  相似文献   
38.
PurposeTo apply M-CHARTS for quantitative measurements of metamorphopsia in eyes with acute branch retinal vein occlusion (BRVO) and to elucidate the pathomorphology that causes metamorphopsia.MethodsThis prospective study consisted of 42 consecutive patients (42 eyes) with acute BRVO. Both at baseline and one month after treatment with ranibizumab, metamorphopsia was measured with M-CHARTS, and the retinal morphological changes were examined with optical coherence tomography.ResultsAt baseline, metamorphopsia was detected in the vertical and/or horizontal directions in 29 (69.0%) eyes; the mean vertical and horizontal scores were 0.59 ± 0.57 and 0.52 ± 0.67, respectively. The maximum inner retinal thickness showed no association with the M-CHARTS score, but the M-CHARTS score was correlated with the total foveal thickness (r = 0.43, p = 0.004), the height of serous retinal detachment (r = 0.31, p = 0.047), and the maximum outer retinal thickness (r = 0.36, p = 0.020). One month after treatment, both the inner and outer retinal thickness substantially decreased. However, metamorphopsia persisted in 26 (89.7%) of 29 eyes. The posttreatment M-CHARTS score was not correlated with any posttreatment morphological parameters. However, the posttreatment M-CHARTS score was weakly correlated with the baseline total foveal thickness (r = 0.35. p = 0.024) and closely correlated with the baseline M-CHARTS score (r = 0.78, p < 0.001).ConclusionsMetamorphopsia associated with acute BRVO was quantified using M-CHARTS. Initial microstructural changes in the outer retina from acute BRVO may primarily account for the metamorphopsia.  相似文献   
39.
It is now known that multicomponent protein assemblies strictly regulate many protein functions. The S100 protein family is known to play various physiological roles, which are associated with alternative complex formations. To prepare sufficient amounts of heterodimeric S100A8 and S100A9 proteins, we developed a method for bicistronic coexpression from a single-vector system using Escherichia coli cells as a host. The complex formation between S100A8 and S100A9 appears to be dependent on the thermodynamic stability of the protein during expression. The stable S100A8/A9 heterodimer complex spontaneously formed during coexpression, and biologically active samples were purified by cation-exchange chromatography. Semi-stable homodimers of S100A8 and S100A9 were also formed when expressed individually. These results suggest that the assembly of S100 protein complexes might be regulated by expression levels of partner proteins in vivo. Because protein assembly occurs rapidly after protein synthesis, coexpression of relevant proteins is crucial for the design of multicomponent recombinant protein expression systems.  相似文献   
40.
Trolox, a water‐soluble vitamin E analogue has been used as a positive control in Trolox equivalent antioxidant capacity and oxygen radical antioxidant capacity assays due to its high antioxidative effect. In this study, the ex vivo antioxidative effects of Trolox and its concentration in blood and brain microdialysates from rat after administration were evaluated by newly established semi‐microflow injection analysis, chemiluminescence detection and HPLC‐UV. In the administration test, the antioxidative effect of Trolox in blood and brain microdialysates after a single administration of 200 mg/kg of Trolox to rats could be monitored. The antioxidative effects in blood (12.0 ± 2.1) and brain (8.4 ± 2.1, × 103 antioxidative effect % × min) also increased. Additionally, the areas under the curve (AUC)s0–360 (n = 3) for blood and brain calculated with quantitative data were 10.5 ± 1.2 and 9.7 ± 2.5 mg/mL × min, respectively. This result indicates that Trolox transferability through the blood–brain barrier is high. The increase in the antioxidative effects caused by Trolox in the blood and brain could be confirmed because good correlations between concentration and antioxidative effects (r ≥ 0.702) were obtained. The fact that Trolox can produce an antioxidative effect in rat brain was clarified. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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