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511.
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Nakayama J Kobayashi T Tanaka S Korenori Y Tateyama A Sakamoto N Kiyohara C Shirakawa T Sonomoto K 《FEMS immunology and medical microbiology》2011,63(3):397-406
We investigated the correlation between fecal bacteria composition in early infancy and the prevalence of allergic diseases in late infancy. The fecal microbiota in the first 2?months was profiled using the 16S rRNA V6 short-tag sequences in the community and statistically compared between two groups of subjects who did and did not show allergic symptoms in the first 2?years (n?=?11 vs. 11). In the allergic group, genus Bacteroides at 1?month and genera Propionibacterium and Klebsiella at 2?months were more abundant, and genera Acinetobacter and Clostridium at 1?month were less abundant than in the nonallergic group. Allergic infants who showed high colonization of Bacteroides and/or Klebsiella showed less colonization of Clostridium perfringens/butyricum, suggesting antagonism between these bacterial groups in the gastrointestinal tract. It was also remarkable that the relative abundance of total Proteobacteria, excluding genus Klebsiella, was significantly lower in the allergic than in the nonallergic group at the age of 1?month. These results indicate that pyrosequence-based 16S rRNA gene profiling is valid to find the intestinal microbiotal disorder that correlates with allergy development in later life. 相似文献
513.
Gabriela G. Oliveira Luciane H. Silveira Eiko N. Itano Rodrigo M. Soares Roberta L. Freire Maria A. E. Watanabe Zoilo P. Camargo Mario A. Ono 《Mycopathologia》2011,171(3):197-202
The objective of this study was to detect antibodies against Paracoccidioides brasiliensis in free-range and caged chickens Gallus domesticus. Initially, the humoral immune response of two chickens immunized with P. brasiliensis was evaluated. Both animals showed the production of antibodies to gp43, the major P. brasiliensis antigen. The seroepidemiological survey was conducted in chickens from the Pantanal region in Mato Grosso do Sul State (free-range
n = 40) and from northern region of Paraná State (free-range n = 100, caged n = 43). The serum samples were analyzed by indirect ELISA using gp43 as antigen. The positivity observed in free-range chickens
from Mato Grosso do Sul (55%) was significantly higher (P = 0.0001) than in free-range chickens from Paraná State (16%). In contrast to the free-range chickens, no positivity was
observed in the caged chickens (P = 0.003). This is the first report showing serological evidence of P. brasiliensis infection in chickens. The results suggest that free-range chickens are more frequently infected by P. brasiliensis, probably due to the constant contact with soil than caged chickens and could be useful as epidemiological markers of paracoccidioidomycosis. 相似文献
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Burgett AW Poulsen TB Wangkanont K Anderson DR Kikuchi C Shimada K Okubo S Fortner KC Mimaki Y Kuroda M Murphy JP Schwalb DJ Petrella EC Cornella-Taracido I Schirle M Tallarico JA Shair MD 《Nature chemical biology》2011,7(9):639-647
Cephalostatin 1, OSW-1, ritterazine B and schweinfurthin A are natural products that potently, and in some cases selectively, inhibit the growth of cultured human cancer cell lines. The cellular targets of these small molecules have yet to be identified. We have discovered that these molecules target oxysterol binding protein (OSBP) and its closest paralog, OSBP-related protein 4L (ORP4L)--proteins not known to be involved in cancer cell survival. OSBP and the ORPs constitute an evolutionarily conserved protein superfamily, members of which have been implicated in signal transduction, lipid transport and lipid metabolism. The functions of OSBP and the ORPs, however, remain largely enigmatic. Based on our findings, we have named the aforementioned natural products ORPphilins. Here we used ORPphilins to reveal new cellular activities of OSBP. The ORPphilins are powerful probes of OSBP and ORP4L that will be useful in uncovering their cellular functions and their roles in human diseases. 相似文献
516.
Kenji Keyamura Chikako Sakaguchi Yoshino Kubota Hironori Niki Takashi Hishida 《The Journal of biological chemistry》2013,288(41):29229-29237
Escherichia coli RecN is an SMC (structural maintenance of chromosomes) family protein that is required for DNA double-strand break (DSB) repair. Previous studies show that GFP-RecN forms nucleoid-associated foci in response to DNA damage, but the mechanism by which RecN is recruited to the nucleoid is unknown. Here, we show that the assembly of GFP-RecN foci on the nucleoid in response to DNA damage involves a functional interaction between RecN and RecA. A novel RecA allele identified in this work, recAQ300R, is proficient in SOS induction and repair of UV-induced DNA damage, but is deficient in repair of mitomycin C (MMC)-induced DNA damage. Cells carrying recAQ300R fail to recruit RecN to DSBs and accumulate fragmented chromosomes after exposure to MMC. The ATPase-deficient RecNK35A binds and forms foci at MMC-induced DSBs, but is not released from the MMC-induced DNA lesions, resulting in a defect in homologous recombination-dependent DSB repair. These data suggest that RecN plays a crucial role in homologous recombination-dependent DSB repair and that it is required upstream of RecA-mediated strand exchange. 相似文献
517.
Gang Fu Chikako Nagasato Toshiaki Ito Dieter G. Müller Taizo Motomura 《Protoplasma》2013,250(1):261-272
Flagellar development in the plurilocular zoidangia of sporophytes of the brown alga Ectocarpus siliculosus was analyzed in detail using transmission electron microscopy and electron tomography. A series of cell divisions in the plurilocular zoidangia produced the spore-mother cells. In these cells, the centrioles differentiated into flagellar basal bodies with basal plates at their distal ends and attached to the plasma membrane. The plasma membrane formed a depression (flagellar pocket) into where the flagella elongated and in which variously sized vesicles and cytoplasmic fragments accumulated. The anterior and posterior flagella started elongating simultaneously, and the vesicles and cytoplasmic fragments in the flagellar pocket fused to the flagellar membranes. The two flagella (anterior and posterior) could be clearly distinguished from each other at the initial stage of their development by differences in length, diameter and the appendage flagellar rootlets. Flagella continued to elongate in the flagellar pocket and maintained their mutually parallel arrangement as the flagellar pocket gradually changed position. In mature zoids, the basal part of the posterior flagellum (paraflagellar body) characteristically became swollen and faced the eyespot region. Electron dense materials accumulated between the axoneme and the flagellar membrane, and crystallized materials could also be observed in the swollen region. Before liberation of the zoospores from the plurilocular zoidangia, mastigoneme attachment was restricted to the distal region of the anterior flagellum. Structures just below the flagellar membrane that connected to the mastigonemes were clearly visible by electron tomography. 相似文献
518.
Chizuru Sasaki Masaki Ichitani Ko-Ki Kunimoto Chikako Asada Yoshitoshi Nakamura 《Bioscience, biotechnology, and biochemistry》2013,77(5):874-877
Arbutin is a tyrosinase inhibitor and is extensively used as a human skin-whitening agent. This study investigated the optimum conditions for extracting arbutin by ultrasonic homogenization from discarded branches pruned from Japanese pear (Pyrus pyrifolia cv. Kousui) trees. The arbutin content was measured in the branches and also in the leaves, stems, fruit peel, and fruit flesh. 相似文献
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