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991.
Nobuyuki Kobayashi Tomoyuki Nagata Shunichiro Shinagawa Naomi Oka Kazuya Shimada Akihiro Shimizu Yoshitaka Tatebayashi Hisashi Yamada Kazuhiko Nakayama Kazuhiro Kondo 《Biochemical and biophysical research communications》2013,430(3):907-911
After infection with herpes simplex virus type 1 (HSV-1), latent infection persists for life in the trigeminal ganglion and reactivation results in an outbreak of cold sores around the mouth. Many previous studies have reported HSV-1 reactivation to be a risk factor for Alzheimer’s disease (AD). This study enrolled subjects with AD (n = 85), subjects with amnestic mild cognitive impairment (aMCI; a prodromal stage of AD) (n = 34), and healthy controls (n = 28). The avidity index of anti-HSV-1 IgG antibodies—a known indicator of HSV-1 reactivation—was measured in order to clarify the relationship between HSV-1 reactivation and symptoms of cognitive function in AD.Cognitive function in AD and aMCI were evaluated using scores from the mini-mental state examination (MMSE) and frontal assessment battery (FAB). The results showed that the subjects with aMCI, for which cerebral function is better preserved than subjects with AD, had a higher anti-HSV-1 IgG antibody avidity index than the AD subjects or healthy controls. Furthermore, the anti-HSV-1 IgG antibody avidity index was even higher in the subjects with high MMSE scores on orientation to time and three-step command subscores. We observed a negative correlation between the anti-HSV-1 IgG antibody avidity index and plasma BDNF concentration, which is an indicator of encephalitis. This suggests that HSV-1 reactivation, as observed through an increase in the anti-HSV-1 IgG avidity index, does not progress to encephalitis. These results suggest that HSV-1 reactivation occurs from the stage of aMCI, which is prodromal to AD, and can affect AD symptoms without an intermediary stage of severe encephalitis. The study demonstrates that the anti-HSV-1 IgG antibody avidity index could be a useful biomarker for the early diagnosis of aMCI as well as AD, and suggests that antiviral medication to treat HSV-1 could play a role in preventing the onset of AD. 相似文献
992.
Koizumi K Nakayama M Zhu WJ Ito S 《Biochemical and biophysical research communications》2011,(2):426-431
Methylglyoxal (MGO) is a toxic and highly reactive alpha-oxoaldehyde, elevated in the states of various diseases underlying enhanced oxidative stress. Furthermore, MGO has been reported to generate another aldehyde, formic acid (FA). In this sense, investigating the biological property of FA is crucially important. The present study examined the effects of MGO and FA on cell viability using the U937 human histiocytic cell line. FA showed a dose-dependent increase in cell viability at the concentrations of MGO in which cell viability decreased. The mechanism of the increase by FA involved the presence of endogenous hydrogen peroxide (H2O2) and tetrahydrofolate in the folate pathway, whereas that of the decrease in cell viability by MGO involved interaction with H2O2 and oxidative damage. These findings suggest that FA production by MGO degradation may play a role in attenuation of oxidative cellular injury caused by MGO. We hypothesize that FA generation pathway constitutes a detoxification system for MGO. 相似文献
993.
Toru Yamazaki Masashi Yamori Shiro Tanaka Keiichi Yamamoto Eriko Sumi Megumi Nishimoto-Sano Keita Asai Katsu Takahashi Takeo Nakayama Kazuhisa Bessho 《PloS one》2013,8(11)
Background
Several studies have reported osteomyelitis of the jaw (OMJ) as a side effect of bisphosphonates (BPs), and the risk of oral BPs has been recently clarified. However, other systemic risk factors of OMJ remain unclear. Importantly, the possibility of risk classification based on the clinical characteristics of patients has not been explored. Here, we clarified risk factors of OMJ and evaluate the predictive accuracy of risk indices in osteoporosis patients.Methods
We performed sub-analysis using a database developed for a retrospective cohort study in patients taking medications for osteoporosis at Kyoto University Hospital. Risk indices for OMJ were constructed using logistic regression analysis, and odds ratios (OR) for OMJ cases and 95% confidence intervals (CI) were estimated. Potential risk factors included in the statistical analysis were age; sex; diabetes; use of oral BPs, corticosteroids, cancer chemotherapy, antirheumatic drugs, and biologic agents; and their interactions. Risk indices were calculated by the sum of potential risk factors of an individual patient multiplied by the regression coefficients. The discriminatory power of the risk indices was assessed by receiver operating characteristic (ROC) analysis.Results
In analysis of all patients, oral BPs (OR: 4.98, 95% CIs: 1.94-12.75), age (OR: 1.28, 95% CI: 1.06-1.60) and sex-chemotherapy interaction (OR: 11.70, 95% CI: 1.46-93.64) were significant risk factors of OMJ. Areas under the ROC curves of these risk indices provided moderate sensitivity or specificity regardless of group (0.683 to 0.718).Conclusions
Our data suggest that oral BP use, age, and sex-chemotherapy are predictors of OMJ in osteoporosis patients. The risk indices are moderately high, and allow the prediction of OMJ incidence. 相似文献994.
The viscosity change of myosin A concentrated solution with or without other components was measured as the incubation time elapsed at 30°C.The viscosity of myosin A solution increased, but that of F-actin solution did not. The shear stress at 0.04 sec?1 was not increased to 1.0 dyne/cm2 in the former, but in the latter was below 0.5 dyne/cm2.The viscosity of myosin B solution increased slightly, but that of native tropomyosin-free myosin B solution decreased remarkably. In both the shear stress at 0.04 sec?1 was greater than or equal to 15 dynes/cm2.The speed of the viscosity increase in the presence of 3 mm pyrophosphate and 3 mm MgCl2 was higher in concentrated solution of myosin B than in that of native tropomysin-free myosin B. The shear stress at 0.04 sec?1 after 6 hr at 30°C was 11.5 and 8.2 dynes/cm2, respectively.The effect of native tropomyosin and actin on the viscosity change was discussed. 相似文献
995.
Yuzuru Sanemitsu Yoshinori Nakayama Satoru Inoue 《Bioscience, biotechnology, and biochemistry》2013,77(11):2913-2914
The interfacial adsorptivity of lysophosphatidylcholine (LPC) was investigated in relation to formation of stable emulsions and interaction of LPC on lipoproteins. The proportion of adsorbed LPC on the interface was measured by using the quantitative interaction between free LPC in an aqueous phase and multilamellar vesicle PC (MLV-PC) that was added after emulsification. Moreover, the effects of free fatty acid on the adsorptivity of LPC were measured by the decrease of LPC-fatty acid vesicles after emulsification. The line widths of 31P-NMR spectra broadened and mean diameters of droplets decreased with the increase of absorptivity. Thus, the restriction of headgroup motional freedom of LPC was correlated with the interaction between LPC and triacylglycerol or free fatty acid on the interface, and the adsorptivity and interaction varied with the fatty acid composition of oil phase and with the emulsifying temperature. 相似文献
996.
Akihiko Matsuo Mitsuru Nakayama Tetsuo Nakamoto Yasuto Uchio Shûichi Hayashi 《Bioscience, biotechnology, and biochemistry》2013,77(4):925-927
One hundred fifty strains of actinomycetes were isolated from soils on plate cultures containing beet arabinan as the sole carbon source. About one-third of the culture fluids were found to have arabinosidase activity. A wild-type strain, Streptomyces sp. No. 17-1, was selected as the best producer of arabinosidase. The highest enzymatic activity was obtained in the culture fluid when the initial pH was adjusted to 9.0. An α-l-arabinofuranosidase was highly purified from the culture filtrate of No. 17-1 by combining column chromatography on DEAE-cellulose, gel filtration on Sephadex G-100, and isoelectric focusing. The molecular weight of the purified enzyme was estimated to be about 92, 000, and its isoelectric point was pH 4.4. The enzymatic activity was maximum at pH 6.0 and was completely inhibited by Hg2+. The apparent Km value of the enzyme for p-nitrophenyl-α-l-arabinofuranoside was determined to be 3.6 mM. 相似文献
997.
Tsutomu Nakayama Fumitaka Hayase Hiromichi Kato 《Bioscience, biotechnology, and biochemistry》2013,77(5):1201-1202
An exo-β-1,3-glucanase was purified from the commercial enzyme preparation “Kitalase” which is a yeast cell wall lytic enzyme preparation. The purification procedures consisted of following steps: ammonium sulfate fraction, SP-Sephadex C-50 and CM-Cellulose C-32 column chromatography, and Sephadex G-100 gel filtration. The optimum pH value was 5.8, and the optimum temperature was 55°C. The enzyme was stable in the pH range of 5.1 to 9.8 and at temperatures below 53°C. The isoelectric point and the molecular weight were estimated to be pH 9.3 and 73000, respectively. The enzyme was shown to bypass β-1,6-linkaged branches to cleave β-1,3-linkages when scleroglucan was used as substrate. The Km values for laminariri, laminari-pentaose, laminaritetraose and laminaritriose were 0.16, 2.01, 2.24 and 1.34 mM, respectively. 相似文献
998.
999.
Yoshinobu Naoshima Hisashi Ike Tomiaki Ogawa Torn Nakayama Hirokiyo Kondo 《Bioscience, biotechnology, and biochemistry》2013,77(8):2151-2153
We investigated the effect of dietary phospholipid (PL) concentrate from bovine milk on the epidermis. Thirteen-week-old hairless male and female mice (Hos:HR-1) were separated into two experimental groups, each fed two experimental diets: the control group and the PL group. The mice were given the experimental diets for 6 weeks. Stratum corneum hydration and transepidermal water loss (TEWL) were measured using Corneometer CM825 and Tewameter TM300 (Courage and Khazaka Electronics, Cologne, Germany) at 3 weeks and 6 weeks. After the feeding period, ceramides in stratum corneum were analyzed. We found that stratum corneum hydration and ceramides in the PL group were significantly higher than those in the control group and that TEWL in the PL group tended to decrease.These results indicate that dietary PL concentrate improves epidermal function by increasing the amount of ceramides, resulting in higher hydration. 相似文献
1000.
Kiyoshi Nakayama Hiroshi Kase Shukuo Kinoshita 《Bioscience, biotechnology, and biochemistry》2013,77(2):282-288
α,ε-Diaminopimelic acid (DAP)-requiring mutants isolated from Aerobacter aerogenes ATCC 8308 and Serratia marcescens ATCC 19180 were found to accumulate N-succinyl-l-diaminopimelic acid (SDAP) which was an intermediate in the biosynthesis of lysine in Escherichia coli. SDAP was isolated from the culture broth and identified by the behavior in paper chromatography, melting point, elementary analysis, infrared spectrum, and optical rotation.The culture conditions for SDAP production by A. aerogenes KY 7049 (DAP?) and S. marcescens KY 8921 (DAP?/Lys?) were investigated. A. aerogenes KY 7049 has an absolute requirement for DAP together with a relative requirement for l-lysine. High levels of DAP (2000~4000 μg/ml) were proved to be favorable for SDAP accumulation, while if lysine along with DAP was added to the fermentation medium, optimal level of DAP for SDAP production was relatively low (about 200 μg/ml at 200 μg/ml of lysine). A variety of compounds which may conceivably affect the course of a fermentation process, i.e., carbon source, inorganic nitrogen source, amino acids, vitamines, precursors, were screened at optimal levels of lysine and DAP. Thus, the amount of SDAP accumulation reached a level of 19.9 mg/ml with the medium containing 10% glucose and 2000 μg/ml of DAP. S. marcescens KY 8921 requires either DAP or lysine for growth. Optimal level of DAP and lysine for SDAP accumulation was 50~100μg/ml. 相似文献