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91.
Yokoro M Suzuki M Yatani M Yamashita H Takahashi Y Tsuji H Kimoto M 《Bioscience, biotechnology, and biochemistry》2012,76(2):400-403
We produced a monoclonal antibody (mAb) against N(G),N(G)-dimethyl-L-arginine (asymmetric dimethylarginine: ADMA), an endogenous competitive inhibitor of nitric oxide synthase (NOS), and developed an enzyme-linked immunosorbent assay (ELISA). The competitive ELISA method using the mAb determined 5 nM-100 nM ADMA, and ADMA levels in human plasma and urine were found to be 0.78 μM and 51.3 μmol/g of creatinine respectively. 相似文献
92.
Combination of hTERT and bmi-1, E6, or E7 induces prolongation of the life span of bone marrow stromal cells from an elderly donor without affecting their neurogenic potential 下载免费PDF全文
Mori T Kiyono T Imabayashi H Takeda Y Tsuchiya K Miyoshi S Makino H Matsumoto K Saito H Ogawa S Sakamoto M Hata J Umezawa A 《Molecular and cellular biology》2005,25(12):5183-5195
Murine bone marrow stromal cells differentiate not only into mesodermal derivatives, such as osteocytes, chondrocytes, adipocytes, skeletal myocytes, and cardiomyocytes, but also into neuroectodermal cells in vitro. Human bone marrow stromal cells are easy to isolate but difficult to study because of their limited life span. To overcome this problem, we attempted to prolong the life span of bone marrow stromal cells and investigated whether bone marrow stromal cells modified with bmi-1, hTERT, E6, and E7 retained their differentiated capability, or multipotency. In this study, we demonstrated that the life span of bone marrow stromal cells derived from a 91-year-old donor could be extended and that the stromal cells with an extended life span differentiated into neuronal cells in vitro. We examined the neuronally differentiated cells morphologically, physiologically, and biologically and compared the gene profiles of undifferentiated and differentiated cells. The neuronally differentiated cells exhibited characteristics similar to those of midbrain neuronal progenitors. Thus, the results of this study support the possible use of autologous-cell graft systems to treat central nervous system diseases in geriatric patients. 相似文献
93.
The objective of this study was to develop an ideal freezing extender and method for rat epididymal sperm cryopreservation. Epididymal sperm collected from 30 Wistar males was frozen, and experiments were conducted to study its post-thaw characteristics when freezing with raffinose-free buffer or various concentrations of raffinose and egg yolk dissolved in distilled and deionised water, PBS, or modified Krebs–Ringer bicarbonate (mKRB)-based extender. Different concentrations of glycerol, Equex STM, or sodium dodecyl sulfate (SDS) dissolved in either PBS or mKRB containing egg yolk were also tested. Based on the data from these experiments, further experiments tested how different sugars such as raffinose, trehalose, lactose, fructose, and glucose dissolved in mKRB with Equex STM, SDS and egg yolk supplementation affected the post-thaw characteristics of cryopreserved sperm. Cryosurvival of frozen-thawed sperm were judged by microscopic assessment of the sperm motility index (SMI), and acrosome integrity was measured using FITC-PNA staining. Thawed sperm were subjected to 3 h of a thermal resistance test. Beneficial effects on the post-thaw survival of sperm were obtained when 0.1 M raffinose in mKRB was used with 0.75% Equex STM, 0.05% SDS, and 20% egg yolk. Sperm cryopreserved with this treatment exhibited a higher motility index and maintained greater SMI and acrosome integrity throughout incubation when compared to sperm frozen in various concentrations of other cryoprotectants and trehalose, lactose, fructose, glucose. In conclusion, cryopreservation in an extender solution of raffinose dissolved in mKRB containing Equex STM, SDS and egg yolk greatly enhances the freezability of rat epididymal sperm. 相似文献
94.
Clostridium cellulovorans, an anaerobic bacterium, produces a small nonenzymatic protein called HbpA, which has a surface layer homology domain and a type I cohesin domain similar to those found in the cellulosomal scaffolding protein CbpA. In this study, we demonstrated that HbpA could bind to cell wall fragments from C. cellulovorans and insoluble polysaccharides and form a complex with cellulosomal cellulases endoglucanase B (EngB) and endoglucanase L (EngL). Synergistic degradative action of the cellulosomal cellulase and HbpA complexes was demonstrated on acid-swollen cellulose, Avicel, and corn fiber. We propose that HbpA functions to bind dockerin-containing cellulosomal enzymes to the cell surface and complements the activity of cellulosomes. 相似文献
95.
96.
Contra-IL 2; a suppressor lymphokine that inhibits IL 2 activity 总被引:3,自引:0,他引:3
T Maki S Satomi M Gotoh A P Monaco 《Journal of immunology (Baltimore, Md. : 1950)》1986,136(9):3298-3303
Suppressive activity of culture supernatant of AS-9 (AS-9 CS), a T cell hybridoma line that was derived from fusion of BW5147 thymoma and splenic T cells of anti-lymphocyte serum-treated C3H mice, was analyzed. AS-9 CS inhibited allogeneic cytotoxic T lymphocyte (CTL) generation as well as T cell proliferation to alloantigens and mitogens, but failed to inhibit B cell response to lipopolysaccharide or growth of tumor and fibroblast cells. Although addition of AS-9 CS to the allogeneic sensitization culture as late as on day 2 of incubation resulted in maximal inhibiton of CTL generation, removal of AS-9 CS on day 3 of incubation abolished its inhibitory effect. Addition of purified IL 2 together with AS-9 CS to the allogeneic sensitization cultures only partially abrogated the suppression. Experiments with IL 2-dependent cytotoxic T cell line (CTLL) showed that AS-9 CS suppressed the IL 2-induced proliferation of CTLL. Preincubation of AS-9 CS with CTLL removed its inhibitory effect on CTL generation. These results indicate that AS-9 CS interferes with the mechanism of T cell activation by IL 2. On this basis, AS-9 CS was named contra-IL 2. 相似文献
97.
Stephen O Opiyo Rosevelt L Pardy Hideaki Moriyama Etsuko N Moriyama 《BMC evolutionary biology》2010,10(1):362
Background
Lipid A is the highly immunoreactive endotoxic center of lipopolysaccharide (LPS). It anchors the LPS into the outer membrane of most Gram-negative bacteria. Lipid A can be recognized by animal cells, triggers defense-related responses, and causes Gram-negative sepsis. The biosynthesis of Kdo2-lipid A, the LPS substructure, involves with nine enzymatic steps. 相似文献98.
Yu Yokoyama Masaki Tanito Koji Nitta Maki Katai Yasushi Kitaoka Kazuko Omodaka Satoru Tsuda Toshiaki Nakagawa Toru Nakazawa 《PloS one》2014,9(6)
PurposeThe Glaucoma Stereo Analysis Study (GSAS), a cross sectional multicenter collaborative study, used a stereo fundus camera to assess various morphological parameters of the optic nerve head (ONH) in glaucoma patients and investigated the relationships between these parameters and patient characteristics.ResultsPatient characteristics included refractive error of −3.38±3.75 diopters, intraocular pressure (IOP) of 13.6±2.6 mmHg, and visual field mean deviation (MD) of −4.71±3.26 dB. Representative ONH parameters included a horizontal disc width of 1.66±0.28 mm, vertical disc width of 1.86±0.23 mm, disc area of 2.42±0.63 mm2, cup area of 1.45±0.57 mm2, and cup volume of 0.31±0.22 mm3. Correlation analysis revealed significant negative associations between vertical cup-to-disc ratio (0.82±0.08) and MD (r = −0.40, P<0.01) and between disc tilt angle (10.5±12.5 degrees) and refractive error (r = −0.36, P<0.01). Seventy-five percent of the eyes had a positive value for rim decentering (0.30±0.42), indicating that rim thinning manifested more often as an inferior lesion than a superior lesion.ConclusionWe used stereoscopic analysis to establish a database of ONH parameters, which may facilitate future studies of glaucomatous changes in ONH morphology. 相似文献
99.
Hiroaki Iidzuka Hideaki Goto Michimasa Yamasaki Naoya Osawa 《Entomological Science》2014,17(2):167-180
Ambrosia beetles (many Scolytinae and all Platypodinae) are one of the most important insect pests for forestry worldwide, but little is known about the community structure of ambrosia beetles in terms of their vertical variations and resource utilization. We clarified the community structure and seasonal population trends of ambrosia beetles on 11 living and three newly dead Fagus crenata Blume trees using individual tube traps placed up to 10 m high from May to November in 2007 and 2008. We captured seven scolytine species (Ambrosiodmus lewisi (Blandford), Euwallacea validus (Eichhoff), Trypodendron proximum (Niisima), Xyleborinus saxeseni (Ratzeburg), Xyleborus atratus Eichhoff, Xylosandrus brevis (Eichhoff) and Xylosandrus germanus (Blandford)) and three platypodine species (Crossotarsus niponicus Blandford, Platypus hamatus Blandford and Platypus severini Blandford). The ambrosia beetles were suggested to breed at species‐specific height ranges, with the equal host resource use per individual among the species. Of the three major species, C. niponicus, P. hamatus and P. severini, two (C. niponicus and P. hamatus) had male‐biased sex ratios, which is considered a reproductive strategy to increase maternal fitness. Morphological characteristics of the mandibles may play an important role in the difference of sex roles on reproduction in the three major species. 相似文献
100.
Sakuraba Y Sezutsu H Takahasi KR Tsuchihashi K Ichikawa R Fujimoto N Kaneko S Nakai Y Uchiyama M Goda N Motoi R Ikeda A Karashima Y Inoue M Kaneda H Masuya H Minowa O Noguchi H Toyoda A Sakaki Y Wakana S Noda T Shiroishi T Gondo Y 《Biochemical and biophysical research communications》2005,336(2):609-616
The large-scale mouse mutagenesis with ENU has provided forward-genetic resources for functional genomics. The frozen sperm archive of ENU-mutagenized generation-1 (G1) mice could also provide a "mutant mouse library" that allows us to conduct reverse genetics in any particular target genes. We have archived frozen sperm as well as genomic DNA from 9224 G1 mice. By genome-wide screening of 63 target loci covering a sum of 197 Mbp of the mouse genome, a total of 148 ENU-induced mutations have been directly identified. The sites of mutations were primarily identified by temperature gradient capillary electrophoresis method followed by direct sequencing. The molecular characterization revealed that all the identified mutations were point mutations and mostly independent events except a few cases of redundant mutations. The base-substitution spectra in this study were different from those of the phenotype-based mutagenesis. The ENU-based gene-driven mutagenesis in the mouse now becomes feasible and practical. 相似文献