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81.
Hnin Thanda Aung Alessio Porta Marco Clericuzio Yoshiaki Takaya Giovanni Vidari 《化学与生物多样性》2017,14(5)
Two new sterols 1 and 2 and five known ones 3 – 7 were isolated for the first time from the fruiting bodies of Cortinarius glaucopus. Their structures were established by 1‐ and 2D‐NMR spectra and HR‐FABS‐MS. The relative configuration of 1 was firmly determined by comparison of the observed 1H–1H couplings and NOESY correlations, with those predicted for the computed geometries of the conformers. Calculations were performed by means of DFT with the B3LYP functional at 6‐31 + G(d,p) level of theory, in CHCl3 as the solvent. The structures of the new ergosterol derivatives, called glaucoposterol A ( 1 ) and B ( 2 ), were thus established as (3S,5R,7R,10R,13R,17R,20S,22R,23R,24R)‐5,6‐epoxy‐3,7,23‐trihydroxystrophast‐8‐en‐14‐one and (22E,3S,5S,9S,10R,13R,17R,20R,24R)‐3,5‐dihydroxyergosta‐6,8(14),22‐trien‐15‐one, respectively. Moreover, the configuration of known strophasterol C ( 3 ) was determined as (3S,5R,6S,7R,10R,13R,17R,20S,22S,24R). Glaucoposterol A ( 1 ) and strophasterol C ( 3 ) represent the second finding in nature of steroids with the rare strophastane skeleton. 相似文献
82.
Induction of an organ-specific autoimmune disease, lymphocytic hypophysitis, in hamsters by recombinant rubella virus glycoprotein and prevention of disease by neonatal thymectomy. 下载免费PDF全文
J W Yoon D S Choi H C Liang H S Baek I Y Ko H S Jun S Gillam 《Journal of virology》1992,66(2):1210-1214
Glycosylated, membrane-associated E1 (58-kDa) and E2 (47- to 49-kDa) rubella virus proteins and unglycosylated nucleoprotein C (33 kDa), from separately expressed vaccinia virus recombinants, were injected into golden Syrian hamsters. Rubella virus E1 and E2 glycoproteins consistently induced an organ-specific autoimmune disease, autoimmune lymphocytic hypophysitis, which was evidenced by the induction of autoantibodies against pituitary cells and by lymphocytic infiltration of the pituitary. Neonatal thymectomy prevented the disease. In contrast, rubella virus nucleoprotein C did not induce either autoantibodies against pituitary cells or lymphocytic infiltration of the pituitary. This finding raises the possibility that virus-specific protein itself can induce an organ-specific autoimmune disease in certain circumstances. 相似文献
83.
DISC1 localizes to the centrosome by binding to kendrin 总被引:1,自引:0,他引:1
Miyoshi K Asanuma M Miyazaki I Diaz-Corrales FJ Katayama T Tohyama M Ogawa N 《Biochemical and biophysical research communications》2004,317(4):1195-1199
Disrupted-In-Schizophrenia 1 (DISC1) was identified as a novel gene disrupted by a (1;11)(q42.1;q14.3) translocation that segregated with major mental disorders in a Scottish family. Using the yeast two-hybrid system, we screened a human brain cDNA library for interactors of the DISC1 protein. One of the positive clones encoded kendrin/pericentrin-B, a giant protein known to localize specifically to the centrosome. The interaction between DISC1 and kendrin in mammalian cells was demonstrated by an immunoprecipitation assay. Residues 446-533 of DISC1 were essential for the interaction with kendrin. Immunocytochemical analysis revealed the colocalization of DISC1 and kendrin to the centrosome. These data indicate that DISC1 localizes to the centrosome by binding to kendrin. Kendrin has been reported to anchor the gamma-tubulin complex to the centrosome, providing microtubule nucleation sites. The present study suggests the possible involvement of DISC1 in the pathophysiology of mental disorders due to its putative effect on centrosomal function. 相似文献
84.
Cheung CH Lin WH Hsu JT Hour TC Yeh TK Ko S Lien TW Coumar MS Liu JF Lai WY Shiao HY Lee TR Hsieh HP Chang JY 《PloS one》2011,6(8):e23485
Background
Over-expression of Aurora kinases promotes the tumorigenesis of cells. The aim of this study was to determine the preclinical profile of a novel pan-Aurora kinase inhibitor, BPR1K653, as a candidate for anti-cancer therapy. Since expression of the drug efflux pump, MDR1, reduces the effectiveness of various chemotherapeutic compounds in human cancers, this study also aimed to determine whether the potency of BPR1K653 could be affected by the expression of MDR1 in cancer cells.Principal Findings
BPR1K653 specifically inhibited the activity of Aurora-A and Aurora-B kinase at low nano-molar concentrations in vitro. Anti-proliferative activity of BPR1K653 was evaluated in various human cancer cell lines. Results of the clonogenic assay showed that BPR1K653 was potent in targeting a variety of cancer cell lines regardless of the tissue origin, p53 status, or expression of MDR1. At the cellular level, BPR1K653 induced endo-replication and subsequent apoptosis in both MDR1-negative and MDR1-positive cancer cells. Importantly, it showed potent activity against the growth of xenograft tumors of the human cervical carcinoma KB and KB-derived MDR1-positive KB-VIN10 cells in nude mice. Finally, BPR1K653 also exhibited favorable pharmacokinetic properties in rats.Conclusions and Significance
BPR1K653 is a novel potent anti-cancer compound, and its potency is not affected by the expression of the multiple drug resistant protein, MDR1, in cancer cells. Therefore, BPR1K653 is a promising anti-cancer compound that has potential for the management of various malignancies, particularly for patients with MDR1-related drug resistance after prolonged chemotherapeutic treatments. 相似文献85.
First record of the tribe Trigonoderini (Hymenoptera: Pteromalidae) from South Korea with descriptions of two new species 下载免费PDF全文
The tribe Trigonoderini (Hymenoptera: Pteromalidae) contains six genera (Gastracanthus Westwood, Janssoniella Kerrich, Miscogasteriella Girault, Platygerrhus Thomson, Plutothrix Förster and Trigonoderus Westwood). This tribe is recorded from South Korea for the first time. Two new species, Janssoniella albiclava Tselikh & Lee sp. nov. from South Korea and J. magna Tselikh & Lee sp. nov. from South Korea and the South Far East of Russia, are described. Eight species (Gastracanthus acutus (Kamijo), G. nigrescens Kamijo, Janssoniella intermedia Hedqvist, Miscogasteriella sulcate (Kamijo), Plutothrix scrobicula Kamijo, P. trifasciata (Thomson), Trigonoderus fraxini Yang and T. nigrocephalus Kamijo) are recorded from South Korea for the first time. The keys for identification of the Eastern–Palearctic species of Janssoniella and Gastracanthus are given and photos of diagnostic characters of the new species are provided. 相似文献
86.
R.P. Herd L. Ko S.E. Weisbrode D.D. Heath 《International journal for parasitology》1984,14(2):141-149
Herd R. P., Ko L., Weisbrode S. E. and Heath D. D. 1984. Sequential morphologic changes in adult Echinococcus granulosus during complement-mediated lysis in vitro. International Journal for Parasltology14:141–149. Sequential changes (5,10, 20, 30,40, 50 min, 1, 2, 3, 4, 5, 6, 7, 8, h) were observed by light, scanning and transmission electron microscopy after 38-day-old adult Echinococcus granulosus were exposed to 50% guinea pig serum in vitro. Early changes within 3 h included contraction of worms, fusion of microtriehes, vacuolization and vesiculization of the distal cytoplasm, followed by rupture of vesicles leading to erosion and loss of the distal cytoplasm. This was most marked in the terminal proglottid but ultimately there was complete erosion of the distal cytoplasm of all proglottids and the scolex. After 3 h there was loss of definition of organelles, apparent edema of the perinuclear cytoplasm and, in some instances, rupture of the circular muscle layer with extrusion of parenchyma. Adult tape-worms exposed to heat-inactivated complement showed none of these changes. Lysis and death of the parasite was attributed to osmotic changes subsequent to the formation of trans-membrane channels induced by complement-mediated attack of the tegument after activation of the alternate pathway by factors present in the cestode tegument. 相似文献
87.
This review focuses on utilization of plant lectins as medical diagnostic reagents and tools. The lectin-related diagnostic
is aimed at detection of several diseases connected to alteration of the glycosylation profiles of cells and at identification
of microbial and viral agents in clinical microbiology. Certain lectins, proposed for or used as diagnostic tools could even
recognize those cellular determinants, which are not detected by available antibodies. Broad information is presented on the
lectinomics field, illustrating that lectin diagnostics might become practical alternative to antibody-based diagnostic products.
In addition, the rising trend of lectin utilization in biomedical diagnostics might initiate a development of innovative methods
based on better analytical technologies. Lectin microarray, a rapid and simple methodology, can be viewed as an example for
such initiative. This technology could provide simple and efficient screening tools for analysis of glycosylation patterns
in biological samples (cellular extracts, tissues and the whole cells), allowing thus personalized detection of changes associated
with carbohydrate-related diseases. 相似文献
88.
D V Lychakov Ia A Vinnikov K A Ko?chev A Boiadzhieva-Mikha?lova I Khristov 《Zhurnal evoliutsionno? biokhimii i fiziologii》1983,19(4):369-373
Rhesus monkeys have been kept in horizontal position under klinostatic or antiorthostatic hypokinetic conditions for 7 and 19 days. Using scanning electron microscope, studies were made of the otolithic membrane of the utricle, the receptor surface of the utricle, crista ampullaris of the lateral semicircular canals, the organ of Corti, the stria vascularis and spiral ligament. No significant differences were found between control and experimental animals. 相似文献
89.
90.