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71.
The cDNA for a novel member of the FGFR family, named HrFGFR, was isolated from a Halocynthia roretzi cDNA library prepared at the mid-tailbud stage. This cDNA was 3507b long, and the deduced amino acid sequence contained a motif characteristic of the vertebrate FGFRs. The existence of a single copy of the FGFR homologue gene in H. roretzi was suggested by restriction site analysis of multiple clones. HrFGFR mRNA was expressed strongly in the posterior region in the epidermis from the middle neurula stage. By contrast, Xenopus FGFR homologues are expressed in the anterior region and are known to induce anterior neural formation. A transition of the region expressing FGFR might have induced the more complicated brain or head formation characteristic of vertebrates.  相似文献   
72.
73.
The recommendations presented here are designed to support easier communication of NMR data and NMR structures of proteins and nucleic acids through unified nomenclature and reporting standards. Much of this document pertains to the reporting of data in journal articles; however, in the interest of the future development of structural biology, it is desirable that the bulk of the reported information be stored in computer-accessible form and be freely accessible to the scientific community in standardized formats for data exchange. These recommendations stem from an IUPAC-IUBMB-IUPAB inter-union venture with the direct involvement of ICSU and CODATA. The Task Group has reviewed previous formal recommendations and has extended them in the light of more recent developments in the field of biomolecular NMR spectroscopy. Drafts of the recommendations presented here have been examined critically by more than 50 specialists in the field and have gone through two rounds of extensive modification to incorporate suggestions and criticisms.  相似文献   
74.
Secondary bile acid-producing bacteria were isolated from human feces to improve our appreciation of the functional diversity and redundancy of the intestinal microbiota. In total, 619 bacterial colonies were isolated using a nutrient-poor agar medium and the level of secondary bile acid formation was examined in each by a liquid culture, followed by thin-layer chromatography. Of five strains analyzed by 16S rRNA gene sequencing and biochemical testing, one was identified as Bacteroides intestinalis AM-1, which was not previously recognized as a secondary bile-acid producer. GC-MS revealed that B. intestinalis AM-1 converts cholic acid (CA) and chenodeoxycholic acid into their 7-oxo derivatives, 7-oxo-deoxycholic acid (7-oxo-DCA) and 7-oxo-lithocholic acid, respectively. Thus, B. intestinalis AM-1 possesses 7α-hydroxysteroid dehydrogenase (7α-HSDH) activity. In liquid culture, B. intestinalis AM-1 showed a relatively higher productivity of 7-oxo-DCA than Escherichia coli HB101 and Bacteroides fragilis JCM11019T, which are known to possess 7α-HSDH activity. The level of 7α-HSDH activity was higher in B. intestinalis AM-1 than in the other two strains under the conditions tested. The 7α-HSDH activity in each of the three strains is not induced by CA; instead, it is regulated in a growth phase-dependent manner.  相似文献   
75.
The purpose of this study was to attempt to find related variables of the canine genome with behavioural traits of dogs maintained and tested in a guide dog facility which provided a relatively uniform environment. The study involved 81 Labrador Retrievers that were being trained as guide dogs. Each dog was taken on walk-out sessions in which the trainer weekly recorded observations that were related to behavioural traits. The records were subjected to key-word analysis of 14 behaviour-related words. A factor analysis on the appearance rate of the 14 key words or phrases resulted in the extraction of six factors that accounted for 67.4% of the variance. Factor 1, referred to as aggressiveness, was significantly related to the success or failure of the dog in qualifying as a guide dog, and was also related to the variable of litter identification. Factor 2, referred to as distraction, was related to the variable of trainer. Factor 3, activity level, was related to the variable of sex, and was significantly related to the polymorphisms of c.471T>C in the solute carrier family 1 ( neuronal/epithelial high affinity glutamate transporter ) member 2 gene and c.216G>A in the catechol-O-methyltransferase gene. The involvement of polymorphisms c.471T>C and c.216G>A in behavioural patterns related to activity level is similar to comparable genetic studies in other mammalian species. These results contribute to a greater understanding of the role of these genes in behaviour.  相似文献   
76.
Peripheral blood mononuclear cell (PBMNC) is one of powerful tools for therapeutic angiogenesis in hindlimb ischemia. However, traditional approaches with transplanted PBMNCs show poor therapeutic effects in severe ischemia patients. In this study, we used autograft models to determine whether hypoxic pretreatment effectively enhances the cellular functions of PBMNCs and improves hindlimb ischemia. Rabbit PBMNCs were cultured in the hypoxic condition. After pretreatment, cell adhesion, stress resistance, and expression of angiogenic factor were evaluated in vitro. To examine in vivo effects, we autografted preconditioned PBMNCs into a rabbit hindlimb ischemia model on postoperative day (POD) 7. Preconditioned PBMNCs displayed significantly enhanced functional capacities in resistance to oxidative stress, cell viability, and production of vascular endothelial growth factor. In addition, autologous transplantation of preconditioned PBMNCs significantly induced new vessels and improved limb blood flow. Importantly, preconditioned PBMNCs can accelerate vessel formation despite transplantation on POD 7, whereas untreated PBMNCs showed poor vascularization. Our study demonstrated that hypoxic preconditioning of PBMNCs is a feasible approach for increasing the retention of transplanted cells and enhancing therapeutic angiogenesis in ischemic tissue.  相似文献   
77.

Background

Recently, combination of tonsillectomy and steroid pulse therapy was reported to be effective as the treatment of the immunoglobulin A nephropathy (IgAN). However, the gene expression difference between the tonsils in patients with IgAN and those in control patients is not established.

Methods

We performed tonsillectomy combined with steroid pulse as a treatment to IgAN, analyzed the gene expression in the tonsils (N = 23) using microarray, compared with those with patients suffering from chronic tonsillitis (N = 22). From some candidate genes related with IgAN, we confirmed the apolipoprotein B messenger RNA-editing enzyme catalytic polypeptides 2 (APOBEC2) gene expression in the tonsil and we also analyzed its expression levels and clinical features.

Results

Up-regulated genes seem to be categorized into two groups. One group belongs to the muscle related genes which might be caused by structural differences. The other group includes the immune system-related genes, such as APOBEC2, CALB2, DUSP27, and CXCL11. APOBEC2 was positively stained in the epithelium and the peripheral region of the germinal center in both tonsils. APOBEC2 expression level was negatively related with serum igg level, but did not correlate with clinical course after tonsillectomy.

Conclusion

We confirmed gene expression differences related with immune system and muscle structure. The APOBEC2 was confirmed to be elevated in the tonsils with IgAN patients, and the gene expression level was negatively related with serum igg level in overall patients. These results might be helpful to reveal the mechanism of IgAN.  相似文献   
78.
We investigated the spatial and temporal distribution of xylans in the cell walls of differentiating earlywood tracheids of Cryptomeria japonica using two different types of monoclonal antibodies (LM10 and LM11) combined with immunomicroscopy. Xylans were first deposited in the corner of the S1 layer in the early stages of S1 formation in tracheids. Cell corner middle lamella also showed strong xylan labeling from the early stage of cell wall formation. During secondary cell wall formation, the innermost layer and the boundary between the S1 and S2 layers (S1/S2 region) showed weaker labeling than other parts of the cell wall. However, mature tracheids had an almost uniform distribution of xylans throughout the entire cell wall. Xylan localization labeled with LM10 antibody was stronger in the outer S2 layer than in the inner layer, whereas xylans labeled with LM11 antibody were almost uniformly distributed in the S2 layer. In addition, the LM10 antibody showed almost no xylan labeling in the S1/S2 region, whereas the LM11 antibody revealed strong xylan labeling in the S1/S2 region. These findings suggest that structurally different types of xylans may be deposited in the tracheid cell wall depending on the developmental stage of, or location in, the cell wall. Our study also indicates that deposition of xylans in the early stages of tracheid cell wall formation may be spatially consistent with the early stage of lignin deposition in the tracheid cell wall.  相似文献   
79.
80.
MyD88 is a cytoplasmic adaptor protein that is critical for Toll-like receptor (TLR) signaling. The subcellular localization of MyD88 is characterized as large condensed forms in the cytoplasm. The mechanism and significance of this localization with respect to the signaling function, however, are currently unknown. Here, we demonstrate that MyD88 localization depends on the entire non-TIR region and that the correct cellular targeting of MyD88 is indispensable for its signaling function. The Toll-interleukin I receptor-resistance (TIR) domain does not determine the subcellular localization, but it mediates interaction with specific TLRs. These findings reveal distinct roles for the TIR and non-TIR regions in the subcellular localization and signaling properties of MyD88.  相似文献   
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