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921.
Iwamoto J Sato Y Takeda T Matsumoto H 《Journal of musculoskeletal & neuronal interactions》2012,12(3):136-143
A randomized controlled trial was conducted to determine the effect of 6 months of whole body vibration (WBV) exercise on physical function in postmenopausal osteoporotic women treated with alendronate. Fifty-two ambulatory postmenopausal women with osteoporosis (mean age: 74.2 years, range: 51-91 years) were randomly divided into two groups: an exercise group and a control group. A four-minute WBV exercise was performed two days per week only in the exercise group. No exercise was performed in the control group. All the women were treated with alendronate. After 6 months of the WBV exercise, the indices for flexibility, body balance, and walking velocity were significantly improved in the exercise group compared with the control group. The exercise was safe and well tolerated. The reductions in serum alkaline phosphatase and urinary cross-linked N-terminal telopeptides of type I collagen during the 6-month period were comparable between the two groups. The present study showed the benefit and safety of WBV exercise for improving physical function in postmenopausal osteoporotic women treated with alendronate. 相似文献
922.
T Yoshida M Ishikawa T Niitsu M Nakazato H Watanabe T Shiraishi A Shiina T Hashimoto N Kanahara T Hasegawa M Enohara A Kimura M Iyo K Hashimoto 《PloS one》2012,7(8):e42676
Background
Meta-analyses have identified serum levels of brain-derived neurotrophic factor (BDNF) as a potential biomarker for major depressive disorder (MDD). However, at the time, commercially available human ELISA kits are unable to distinguish between proBDNF (precursor of BDNF) and mature BDNF because of limited BDNF antibody specificity. In this study, we examined whether serum levels of proBDNF, mature BDNF, and matrix metalloproteinase-9 (MMP-9), which converts proBDNF to mature BDNF, are altered in patients with MDD.Methodology/Principal Findings
Sixty-nine patients with MDD and 78 age- and gender-matched healthy subjects were enrolled. Patients were evaluated using 17 items on the Structured Interview Guide for the Hamilton Depression Rating Scale. Cognitive impairment was evaluated using the CogState battery. Serum levels of proBDNF, mature BDNF, and MMP-9 were measured using ELISA kits. Serum levels of mature BDNF in patients with MDD were significantly lower than those of normal controls. In contrast, there was no difference in the serum levels of proBDNF and MMP-9 between patients and normal controls. While neither proBDNF nor mature BDNF serum levels was associated with clinical variables, there were significant correlations between MMP-9 serum levels and the severity of depression, quality of life scores, and social function scores in patients.Conclusions/Significance
These findings suggest that mature BDNF may serve as a biomarker for MDD, and that MMP-9 may play a role in the pathophysiology of MDD. Further studies using larger sample sizes will be needed to investigate these results. 相似文献923.
H Matsumoto K Shibasaki M Uchigashima A Koizumi M Kurachi Y Moriwaki H Misawa K Kawashima M Watanabe S Kishi Y Ishizaki 《PloS one》2012,7(8):e42841
It has been long speculated that specific signals are transmitted from photoreceptors to the retinal pigment epithelium (RPE). However, such signals have not been identified. In this study, we examined the retinal expression and localization of acetylcholine-related molecules as putative candidates for these signals. Previous reports revealed that α7 nicotinic acetylcholine receptors (nAChRs) are present in the microvilli of RPE cells that envelope the tips of photoreceptor outer segments (OS). Secreted mammalian leukocyte antigen 6/urokinase-type plasminogen activator receptor-related protein-1 (SLURP-1) is a positive allosteric modulator of the α7 nAChR. Therefore, we first focused on the expression of SLURP-1. SLURP-1 mRNA was expressed in the outer nuclear layer, which is comprised of photoreceptor cell bodies. SLURP-1 immunoreactivity co-localized with rhodopsin and S-opsin in photoreceptor OS, while choline acetyltransferase (ChAT) and high affinity choline transporter (CHT-1) were also expressed in photoreceptor OS. Immunoelectron microscopy identified that the majority of SLURP-1 was localized to the plasma membranes of photoreceptor OS. These results provide evidence that SLURP-1 is synthesized in photoreceptor cell bodies and transported to photoreceptor OS, where SLURP-1 may also be secreted. Our findings suggest that photoreceptor OS communicate via neurotransmitters such as ACh and SLURP-1, while RPE cells might receive these signals through α7 nAChRs in their microvilli. 相似文献
924.
Background
The involvement of local and systemic oxidative stress in intraocular pressure (IOP) elevation and optic nerve damage has been hypothesized in the pathogenesis of glaucoma. To test this, we measured the systemic levels of prooxidants and antioxidants by analyzing the blood biochemistry in patients with glaucoma.Methods
Peripheral blood samples were collected from Japanese patients with primary open-angle glaucoma (PG) (n = 206), exfoliation syndrome (EX) (n = 199), and controls (n = 126). Plasma levels of lipid peroxides, ferric-reducing activity, and thiol antioxidant activity were measured by diacron reactive oxygen metabolites (dROM), biological antioxidant potential (BAP), and sulfhydryl (SH) tests, respectively, using a free radical analyzer.Results
In the PG, EX, and control groups, the mean ± standard deviation values were 355±63, 357±69, and 348±56 (U. Carr), respectively, for dROM; 1,951±282, 1,969±252, and 2,033±252 (µmol/L), respectively, for BAP (µmol/L); and 614±98, 584±91, and 617±99 (µmol/L), respectively, for SH. The differences in the BAP values were significant between the PG and control groups (p = 0.0062), for SH between the EX and control groups (p = 0.0017), and for SH between the PG and EX groups (p = 0.0026). After adjustment for differences in age and sex among groups using multiple regression analysis, lower BAP values were correlated significantly with PG (p = 0.0155) and EX (p = 0.0049). Higher dROM values with and without glaucoma were correlated with female gender, and lower SH values with older age. There were no significant differences between the higher (≥21 mmHg) and lower (<21 mmHg) baseline IOPs in the PG group or between the presence or absence of glaucoma in the EX group.Conclusions
Lower systemic antioxidant capacity that measured by ferric-reducing activity is involved in the pathogenesis of PG and EX. 相似文献925.
The Col2a1 gene is expressed in notochord, otic vesicle, cartilaginous tissue and the anlage of endochondral bone during development in higher vertebrates. Type II collagen, a homotrimeric product of the Col2a1 gene, functions as a key regulatory protein for cartilage development and endochondral ossification. In medaka and zebrafish, a single homolog of the col2a1 gene has been identified. However, it is necessary to note that many genes are duplicated in teleost fishes. To clarify function of col2a1 genes in teleost fishes and to further understand the process of cartilage development and endochondral ossification, we cloned and mapped the gene loci of two col2a1 orthologs in medaka. The proteins encoded by both medaka col2a1a and col2a1b genes were highly conserved (85.3% and 82.6%) relative to human COL2A1, but synteny was not observed. We also examined the expression patterns of col2a1a and col2a1b during embryonic development. Whole-mount insitu hybridization data suggests that expression patterns of both medaka co2a1a and col2a1b genes are similar to that of zebrafish co2a1 in the early embryonic stages. In medaka, the two col2a1 genes show a closely correlated pattern of spatial and temporal expression. In late embryonic stages, however, there were differences in both expression patterns in the pectoral fin. This study is the first report of two homologs of col2a1 in teleosts and also the first examination of col2a1a and col2a1b expression patterns in this group. 相似文献
926.
Yamaguchi K Matsumoto H Ochiai M Tsuzuki S Hayakawa Y 《Insect biochemistry and molecular biology》2012,42(3):183-192
Growth rates of immature animals are governed by their feeding activities. A reduction in feeding sometimes causes serious growth retardation in insects; a typical case is often seen in host insects parasitized by a solitary endoparasitoid wasp. However, understanding of the mechanisms underlying the physiological repression of parasitized insects is fragmentary. Here we analyzed brain gene expression of the host common cutworm, Spodoptera litura, parasitized by a solitary endoparasitoid, Microplitis manilae, and identified a novel gene whose expression was significantly enhanced by parasitization. The gene encoded a pre-pro-peptide of a cytokine-like molecule and its expression was observed mainly in nervous tissues, hemocytes, and integuments. The 25 amino acid cytokine-like peptide encoded by the C-terminus of this gene was demonstrated to exist in the hemolymph of S. litura larvae and to change hemocytes from non-adhesive to adhesive in vitro. Further, injection of the active peptide reduced feeding activities of test larvae and consequently delayed their growth. The enhanced gene expression was also observed in larvae under severe stress conditions: abdominal ligature, proleg cutting, mechanical vibration, low temperature, and heat shock at 45 °C. Elevated gene expression was maintained only in seriously growth-retarded larvae but not in recovered larvae at 24 h or 48 h after heat treatment. Thus, it is reasonable to conclude that stress-induced elevation of the peptide gene expression highly correlates with reduced feeding activities and growth retardation of the host larvae parasitized by M. manilae. Based on the conclusion, we named this peptide stress-responsive peptide (SRP). 相似文献
927.
M Shinada F Narumi Y Osada K Matsumoto T Yoshida K Higuchi T Kawasaki H Tanaka M Satoh 《Bioorganic & medicinal chemistry》2012,20(16):4901-4914
Phenserine is a potentially attractive drug for Alzheimer's disease. In order to further expand SAR study for inhibitions of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), the methyl group at the 3a-position of phenserine was replaced with an alkyl or alkenyl group, and its phenylcarbamoyl moiety was substituted at the o- or p-position. The synthetic methodology for these phenserine analogues includes the efficient cascade reactions for introduction of the 3a-substituent and assembly of the quaternary carbon center followed by reductive cyclization to the key pyrroloindoline structure. The bulkiness of the substituent at 3a-position of phenserine derivatives tends to reduce the inhibitory effect on AChE activity in the following order: methyl>ethyl>vinyl>propyl≈allyl>reverse-prenyl groups. Among the series synthesized, the 3a-ethyl derivative demonstrated the highest AChE selectivity. In construct, the 3a-reverse-prenyl derivative indicated modest BuChE selectivity. 相似文献
928.
Yamamoto S Matsunaga N Hitaka T Yamada M Hara T Miyazaki J Santou T Kusaka M Yamaoka M Kanzaki N Furuya S Tasaka A Hamamura K Ito M 《Bioorganic & medicinal chemistry》2012,20(1):422-434
A series of 4-phenylpyrrole derivatives D were designed, synthesized, and evaluated for their potential as novel orally available androgen receptor antagonists therapeutically effective against castration-resistant prostate cancers. 4-Phenylpyrrole compound 1 exhibited androgen receptor (AR) antagonistic activity against T877A and W741C mutant-type ARs as well as wild-type AR. An arylmethyl group incorporated into compound 1 contributed to enhancement of antagonistic activity. Compound 4n, 1-{[6-chloro-5-(hydroxymethyl)pyridin-3-yl]methyl}-4-(4-cyanophenyl)-2,5-dimethyl-1H-pyrrole-3-carbonitrile exhibited inhibitory effects on tumor cell growth against the bicalutamide-resistant LNCaP-cxD2 cell line as well as the androgen receptor-dependent JDCaP cell line in a mouse xenograft model. These results demonstrate that this series of pyrrole compounds are novel androgen receptor antagonists with efficacy against prostate cancer cells, including castration-resistant prostate cancers such as bicalutamide-resistant prostate cancer. 相似文献
929.
The combination of histone posttranslational modifications occurring in nucleosomal histones determines the epigenetic code. Histone modifications such as acetylation are dynamically controlled in response to a variety of signals during the cell cycle and differentiation, but they are paradoxically maintained through cell division to impart tissue specific gene expression patterns to progeny. The dynamics of histone modifications in living cells are poorly understood, because of the lack of experimental tools to monitor them in a real-time fashion. Recently, FRET-based imaging probes for histone H4 acetylation have been developed, which enabled monitoring of changes in histone acetylation during the cell cycle and drug treatment. Further development of this type of fluorescent probes for other modifications will make it possible to visualize complicated epigenetic regulation in living cells. 相似文献
930.
M Hara-Yokoyama M Kukimoto-Niino K Terasawa S Harumiya KA Podyma-Inoue N Hino K Sakamoto S Itoh N Hashii Y Hiruta N Kawasaki C Mishima-Tsumagari Y Kaitsu T Matsumoto M Wakiyama M Shirouzu T Kasama H Takayanagi N Utsunomiya-Tate K Takatsu T Katada Y Hirabayashi S Yokoyama M Yanagishita 《Structure (London, England : 1993)》2012,20(9):1585-1595
The leukocyte cell-surface antigen CD38 is the major nicotinamide adenide dinucleotide glycohydrolase in mammals, and its ectoenzyme activity is involved in calcium mobilization. CD38 is also a raft-dependent signaling molecule. CD38 forms a tetramer on the cell surface, but the structural basis and the functional significance of tetramerization have remained unexplored. We identified the interfaces contributing to the homophilic interaction of mouse CD38 by site-specific crosslinking on the cell surface with an expanded genetic code, based on a crystallographic analysis. A combination of the three interfaces enables CD38 to tetramerize: one interface involving the juxtamembrane α-helix is responsible for the formation of the core dimer, which is further dimerized via the other two interfaces. This dimerization of dimers is required for the catalytic activity and the localization of CD38 in membrane rafts. The glycosylation prevents further self-association of the tetramer. Accordingly, the tetrameric interaction underlies the multifaceted actions of CD38. 相似文献