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961.
962.
Kuniko Akama Tomoe Horikoshi Atsushi Sugiyama Satoko Nakahata Aoi Akitsu Nobuyoshi Niwa Atsushi Intoh Yasutaka Kakui Michiko Sugaya Kazuo Takei Noriaki Imaizumi Takaya Sato Rena Matsumoto Hitoshi Iwahashi Shin-ichi Kashiwabara Tadashi Baba Megumi Nakamura Tosifusa Toda 《Biochimica et Biophysica Acta - Proteins and Proteomics》2010,1804(6):1272-1284
In mammalian spermiogenesis, sperm mature during epididymal transit to get fertility. The pig sharing many physiological similarities with humans is considered a promising animal model in medicine. We examined the expression profiles of proteins from boar epididymal caput, corpus, and cauda sperm by two-dimensional gel electrophoresis and peptide mass fingerprinting. Our results indicated that protein disulfide isomerase-P5 (PDI-P5) human homolog was down-regulated from the epididymal corpus to cauda sperm, in contrast to the constant expression of protein disulfide isomerase A3 (PDIA3) human homolog. To examine the functions of PDIA3 and PDI-P5, we cloned and sequenced cDNAs of pig PDIA3 and PDI-P5 protein precursors. Each recombinant pig mature PDIA3 and PDI-P5 expressed in Escherichia coli showed thiol-dependent disulfide reductase activities in insulin turbidity assay. Although PDIA3 showed chaperone activity to promote oxidative refolding of reduced denatured lysozyme, PDI-P5 exhibited anti-chaperone activity to inhibit oxidative refolding of lysozyme at an equimolar ratio. SDS-PAGE and Western blotting analysis suggested that disulfide cross-linked and non-productively folded lysozyme was responsible for the anti-chaperone activity of PDI-P5. These results provide a molecular basis and insights into the physiological roles of PDIA3 and PDI-P5 in sperm maturation and fertilization. 相似文献
963.
A three-dimensional angiographic analysis of the deep palmar arterial arches and their correlating arteries in Cercopithecidae, Pongidae and Hominidae revealed the following features. In Cercopithecidae, 3 deep palmar arches are formed by the perforating branches of the 2nd dorsal metacarpal artery: 2 proximal arches (the catella volaris proximalis and the arcus volaris profundus) and 1 distal arch (the catella volaris distalis). The intermetacarpal arteries arise from the catella volaris proximalis and the palmar metacarpal arteries arise from the arcus volaris profundus. In Pongidae, the arches are formed by the perforating branches of the 1st dorsal metacarpal artery, and they are composed of only the catella volaris proximalis and catella volaris distalis. In Hominidae, the arches are formed by the perforating branches of the 1st dorsal metacarpal artery, and they consist of the arcus volaris profundus and an incomplete catella volaris distalis. 相似文献
964.
Masako Matsumoto Yoshiteru Hashimoto Yuki Saitoh Takuto Kumano 《Bioscience, biotechnology, and biochemistry》2016,80(6):1230-1237
An inducible expression vector, pSH19, which harbors regulatory expression system PnitA-NitR, for streptomycetes was constructed previously. Here, we have modified pSH19 to obtain shuttle vectors for Streptomyces-E. coli by introducing the replication origin of a plasmid for E. coli (ColE1) and an antibiotic-resistant gene. Six inducible shuttle vectors, pESH19cF, pESH19cR, pESH19kF, pESH19kR, pESH19aF, and pESH19aR, for Streptomyces-E. coli, were successfully developed. The stability of these vectors was examined in five different E. coli strains and Streptomyces lividans TK24. The stability test showed that the pSH19-derived shuttle vectors were stable in E. coli Stbl2 and S. lividans TK24. Heterologous expression experiments involving each of the catechol 2,3-dioxygenase, nitrilase, and N-substituted formamide deformylase genes as a reporter gene showed that pESH19cF, pESH19kF, and pESH19aF possess inducible expression ability in S. lividans TK24. Thus, these vectors were found to be useful expression tools for experiments on both Gram-negative and Gram-positive bacterial genes. 相似文献
965.
Tetsu Yamane Masako Mitsumata Noriko Yamaguchi Tadao Nakazawa Kunio Mochizuki Tetsuo Kondo Tomonori Kawasaki Shin-ichi Murata Yoji Yoshida Ryohei Katoh 《Cell and tissue research》2010,340(3):471-479
Remodeling of endothelial basement membrane is important in atherogenesis. Since little is known about the actual relationship
between type IV collagen and matrix metalloprotease−2 (MMP-2) in endothelial cells (ECs) under shear stress by blood flow,
we performed quantitative analysis for type IV collagen and MMP-2 in ECs under high shear stress. The mRNA of type IV collagen
from ECs exposed to high shear stress (10 and 30 dyn/cm2) had a higher expression compared to ECs exposed to a static condition or low shear stress (3 dyn/cm2) (P < 0.01). 3H-proline uptake analysis and fluorography revealed a remarkable increase of type IV collagen under high shear stress (P < 0.01). In contrast, zymography revealed that exposing to high shear stress, however similar positivity was leveled in the
intracellular MMP-2 in the control and high shear stress-exposed ECs, reduced the secretion of MMP-2 in ECs. The results of
Northern blotting, gelatin zymography and monitoring the intracellular trafficking of GFP-labeled MMP-2 revealed that MMP-2
secretion by ECs was completely suppressed by high shear stress, but the intracellular mRNA expression, protein synthesis,
and transport of MMP-2 were not affected. In conclusion, we suggest that high shear stress up-regulates type IV collagen synthesis
and down-regulates MMP-2 secretion in ECs, which plays an important role in remodeling of the endothelial basement membrane
and may suppress atherogenesis. 相似文献
966.
967.
F.?HyodoEmail author Y.?Takematsu T.?Matsumoto Y.?Inui T.?Itioka 《Insectes Sociaux》2011,58(3):417-426
Despite the recognition of the functional role of Hymenoptera (ants, bees and wasps) and Isoptera (termites) in tropical ecosystems,
their detailed feeding habits are not well known. To examine the feeding habits of these groups, we measured nitrogen (N)
and carbon (C) stable isotope ratios (δ15N and δ13C) of hymenopterans (12 families, ≥16 genera and ≥32 species) and isopterans (one family and 10 species) collected in a tropical
rain forest, Sarawak, Malaysia. We compared the isotopic signatures of these insects to those previously reported for other
consumers collected in the same forest. The δ15N and δ13C values of these insects overlapped with those of the other consumers, indicating that they have access to diverse C and
N sources in the forest. The δ15N values of ants and termites indicated that their feeding habits range along a continuum from herbivory (i.e. dependent on
honeydew and nectar) to predation and from wood-feeders to soil-feeders, respectively. In addition, the δ15N values of wasps varied greatly from −0.1‰ (Braconidae sp.) to 8.6‰ (Bembix sp.), suggesting that their feeding habits also range from omnivory to predation. The ant species Camponotus gigas had δ13C values similar to those of invertebrate detritivores and omnivores rather than to those of invertebrate herbivores, although
the diet of this species consists mostly of honeydew. This discrepancy suggests that the ant uses carbohydrates as an energy
source, the isotopic signatures of which are not well retained in the body tissues. Values of both δ15N and δ13C of the predatory army ant Leptogenys diminuta and the soil-feeding termite Dicuspiditermes nemorosus did not differ significantly, indicating that both trophic level and the humification of feeding substrates can increase
the isotopic signatures of terrestrial consumers. 相似文献
968.
969.
Ryu K Li L Khrestian CM Matsumoto N Sahadevan J Ruehr ML Van Wagoner DR Efimov IR Waldo AL 《American journal of physiology. Heart and circulatory physiology》2007,293(2):H1231-H1241
The canine sterile pericarditis model is characterized by impaired conduction and atrial arrhythmia vulnerability. Electrical and structural remodeling processes caused by the inflammatory response likely promote these abnormalities. In the present study, we tested the hypothesis that altered distribution of atrial connexins is associated with markedly abnormal atrial conduction, thereby contributing to vulnerability to atrial flutter (AFL) and atrial fibrillation (AF) induction and maintenance. During rapid pacing and induced, sustained AFL or AF in five sterile pericarditis (SP) and five normal (NL) dogs, epicardial atrial electrograms were recorded simultaneously from both atria (380 electrodes) or from the right atrium (RA) and Bachmann's bundle (212 electrodes). Tissues from RA sites were subjected to immunostaining and immunoblotting to assess connexin (Cx) 40 and Cx43 distribution and expression. Transmural myocyte (alpha-actinin) and fibroblast (vimentin) volume were also assessed by immunostaining. RA pacing maps showed markedly abnormal conduction in SP, with uniform conduction in NL. Total RA activation time was significantly prolonged in SP vs. NL at 300-ms and 200-ms pacing-cycle lengths. Sustained arrhythmias were only inducible in SP [total: 4/5 (AFL: 3/5; AF: 1/5)]. In NL, Cx40, Cx43, alpha-actinin, and vimentin were homogeneously distributed transmurally. In SP, Cx40, Cx43, and alpha-actinin were absent epicardially, decreased midmyocardially, and normal endocardially. SP increased epicardial vimentin expression, suggesting fibroblast proliferation. Immunoblot analysis confirmed reduced expression of Cx40 and Cx43 in SP. The transmural gradient in the volume fraction of Cx40 and Cx43 in SP is associated with markedly abnormal atrial conduction and is likely an important factor in the vulnerability to induction and maintenance of AFL/AF in SP. 相似文献
970.
Y. Yamagata K. Sasaki O. Takaoka S. Sano K. Inomata K. Kanemitsu Y. Inoue I. Matsumoto 《Origins of life and evolution of the biosphere》1990,20(5):389-399
By heating an aqueous solution of aspartic acid and urea, carbamylaspartic acid is first formed and then the molecule is cyclized to dihydroorotic acid (DHO) with loss of water. Irradiation of an aqueous solution of DHO with a tungsten lamp yields orotic acid by photo-dehydrogenation of the molecule. This pathway of orotic acid formation is quite similar to that of biosynthesis of the molecule. 相似文献