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排序方式: 共有1685条查询结果,搜索用时 31 毫秒
1.
Nilson de Jesus Carlos Débora Alves Pinto Mario Augusto Ono Emerson Jose Venancio Zoilo Pires de Camargo Ayako Sano Eiko Nakagawa Itano 《Microbiology and immunology》2014,58(3):212-214
This study investigated the major soluble antigens produced by Paracoccidioides brasiliensis (Pb339) cultured in solid Sabouraud (pH 5.6 and 8.5), Sabouraud plus brain heart infusion and liquid tomato juice‐enriched complex medium media at intervals of 3 days over 30 days by immunoblotting and concluded that, to optimize the source of each antigen, both time and growth conditions should be considered. 相似文献
2.
A novel membrane protein involved in protein translocation across the cytoplasmic membrane of Escherichia coli. 总被引:18,自引:6,他引:12 下载免费PDF全文
A novel factor, which is a membrane component of the protein translocation machinery of Escherichia coli, was discovered. This factor was found in the trichloracetic acid-soluble fraction of solubilized cytoplasmic membrane. The factor was purified to homogeneity by ion exchange column chromatographies and found to be a hydrophobic protein with a molecular mass of approximately 12 kDa. The factor caused > 20-fold stimulation of the protein translocation when it was reconstituted into proteoliposomes together with SecE and SecY. SecE, SecY, SecA and ATP were essential for the factor-dependent stimulation of the activity. The factor stimulated the translocation of all three precursor proteins examined, including authentic proOmpA. Stimulation of the translocation of proOmpF-Lpp, a model presecretory protein, was especially remarkable, since no translocation was observed unless proteoliposomes were reconstituted with the factor. Partial amino acid sequence of the purified factor was determined. An antibody raised against a synthetic peptide of this sequence inhibited the protein translocation into everted membrane vesicles, indicating that the factor is playing an important role in protein translocation into membrane vesicles. The partial amino acid sequence was found to coincide with that deduced from the reported DNA sequence of the upstream region of the leuU gene. Cloning and sequencing of the upstream region revealed the presence of a new open reading frame, which encodes a hydrophobic protein of 11.4 kDa. We propose that the factor is a general component of the protein translocation machinery of E. coli. 相似文献
3.
T Murakami T Nishiyama T Shirotani Y Shinohara M Kan K Ishii F Kanai S Nakazuru Y Ebina 《The Journal of biological chemistry》1992,267(13):9300-9306
4.
Nishiyama N 《Biophysical chemistry》1994,52(2):139-143
We present a model of limit cycle oscillators for collective oscillations in intracellular calcium concentration in cell communities. A phase-dependent discrete coupling between nearest neighbors is introduced into the model on the basis of the experimental observation that intercellular transmission of calcium or calcium mobilizing messenger is effected by gap junction and gap junctional permeability is affected by intracellular calcium concentration. The spatial phase pattern of several clusters in which oscillations are in phase is found with the phase-dependent discrete coupling. 相似文献
5.
K Yorimitsu O Shinmi M Nishiyama K Moroi Y Sugita T Saito Y Inagaki T Masaki S Kimura 《FEBS letters》1992,314(3):395-398
The biosynthetic pathway of endothelin (ET)-2 was analyzed in cultured ACHN cells. In the supernatant, we detected three ET-2-related peptides, ET-2, big ET-2(1-38) and big ET-2(22-38). Phosphoramidon decreased the amount of ET-2 and increased that of big ET-2(1-38) dose-dependently. The amount of big ET-2(1-37) did not significantly change. These results suggest that big ET-2 is composed of 38 and not 37 amino acid residues, and that a putative ET-2-converting enzyme (ECE-2) should be classified as a phosphoramidon-sensitive neutral metalloprotease, bearing a resemblance to the putative ET-1-converting enzyme (ECE-1) in endothelial cells. 相似文献
6.
Manami Matsumoto Mami Nishiyama Hayato Maeda Akio Tonouchi Katsuhiro Konno Masaru Hashimoto 《Bioorganic & medicinal chemistry letters》2019,29(8):982-985
The novel trichothecene 12-deoxytrichodermin (3) was isolated from the fungus Trichoderma sp. 1212-03, and included with other known natural trichothecenes in a structure-activity relationship investigation against a human colon cancer cell line (COLO201) and filamentous fungus Cochliobolus miyabeanus. This revealed that the 12-epoxide functionality is critical for the cytotoxicity of simple trichothecenes trichodermin (4) and deoxynivalenol (2), while not critical for the cytotoxicity of roridin J (6) and epiisororidin E (8). In contrast, 12-epoxide is essential for the antifungal activity. 相似文献
7.
Hirohito Mori Hideki Kobara Takaaki Tsushimi Noriko Nishiyama Shintaro Fujihara Tsutomu Masaki 《PloS one》2015,10(4)
Objective
Objective evaluation of resected specimen and tumor size is critical because the tumor diameter after endoscopic submucosal dissection affects therapeutic strategies. In this study, we investigated whether the true tumor diameter of gastrointestinal cancer specimens measured by flexible endoscopy is subjective by testing whether the specimen is correctly attached to the specimen board after endoscopic submucosal dissection resection and whether the size differs depending on the endoscopist who attached the specimen.Methods
Seventy-two patients diagnosed with early gastric cancer who satisfied the endoscopic submucosal dissection expanded-indication guideline were enrolled. Three endoscopists were randomly selected before every endoscopic submucosal dissection. Each endoscopist separately attached the same resected specimen, measured the maximum resection diameter and tumor size, and removed the lesion from the attachment board.Results
The resected specimen diameters of the 3 endoscopists were 44.5±13.9 mm (95% Confidence Interval (CI): 23–67), 37.4±12.0 mm (95% CI: 18–60), and 41.1±13.3 mm (95% CI: 20–63) mm. Comparison among 3 groups (Kruskal Wallis H- test), there were significant differences (H = 6.397, P = 0.040), and recorded tumor sizes were 38.3±13.1 mm (95% CI: 16–67), 31.1±11.2 mm (95% CI: 12.5–53.3), and 34.8±12.8 (95% CI: 11.5–62.3) mm. Comparison among 3 groups, there were significant differences (H = 6.917, P = 0.031).Conclusions
Human errors regarding the size of attached resected specimens are unavoidable, but it cannot be ignored because it affects the patient’s additional treatment and/or surgical intervention. We must develop a more precise methodology to obtain accurate tumor size.Trial Registration
University hospital Medical Information Network UMIN No. 000012915 相似文献8.
Cohesin is a ring‐shaped protein complex that plays a crucial role in sister chromatid cohesion and gene expression. The dynamic association of cohesin with chromatin is essential for these functions. However, the exact nature of cohesin dynamics, particularly cohesin translocation, remains unclear. We evaluated the dynamics of individual cohesin molecules on DNA and found that the cohesin core complex possesses an intrinsic ability to traverse DNA in an adenosine triphosphatase (ATPase)‐dependent manner. Translocation ability is suppressed in the presence of Wapl‐Pds5 and Sororin; this suppression is alleviated by the acetylation of cohesin and the action of mitotic kinases. In Xenopus laevis egg extracts, cohesin is translocated on unreplicated DNA in an ATPase‐ and Smc3 acetylation‐dependent manner. Cohesin movement changes from bidirectional to unidirectional when cohesin faces DNA replication; otherwise, it is incorporated into replicating DNA without being translocated or is dissociated from replicating DNA. This study provides insight into the nature of individual cohesin dynamics and the mechanisms by which cohesin achieves cohesion in different chromatin contexts. 相似文献
9.
Sequence Analysis of Amplified DNA Fragments Containing the Region Encoding the Putative Lipase Substrate-Binding Domain and Genotyping of Aeromonas hydrophila 下载免费PDF全文
Noboru Watanabe Koji Morita Tomoko Furukawa Taki Manzoku Eiko Endo Masato Kanamori 《Applied microbiology》2004,70(1):145-151
DNA fragments were amplified by PCR from all tested strains of Aeromonas hydrophila, A. caviae, and A. sobria with primers designed based on sequence alignment of all lipase, phospholipase C, and phospholipase A1 genes and the cytotonic enterotoxin gene, all of which have been reported to have the consensus region of the putative lipase substrate-binding domain. All strains showed lipase activity, and all amplified DNA fragments contained a nucleotide sequence corresponding to the substrate-binding domain. Thirty-five distinct nucleotide sequence patterns and 15 distinct deduced amino acid sequence patterns were found in the amplified DNA fragments from 59 A. hydrophila strains. The deduced amino acid sequences of the amplified DNA fragments from A. caviae and A. sobria strains had distinctive amino acids, suggesting a species-specific sequence in each organism. Furthermore, the amino acid sequence patterns appear to differ between clinical and environmental isolates among A. hydrophila strains. Some strains whose nucleotide sequences were identical to one another in the amplified region showed an identical DNA fingerprinting pattern by repetitive extragenic palindromic sequence-PCR genotyping. These results suggest that A. hydrophila, and also A. caviae and A. sobria strains, have a gene encoding a protein with lipase activity. Homologs of the gene appear to be widely distributed in Aeromonas strains, probably associating with the evolutionary genetic difference between clinical and environmental isolates of A. hydrophila. Additionally, the distinctive nucleotide sequences of the genes could be attributed to the genotype of each strain, suggesting that their analysis may be helpful in elucidating the genetic heterogeneity of Aeromonas. 相似文献
10.