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61.
Diverticular disease of the colon was detected in a female Japanese monkey by X-ray examination. The monkey was 15 years old and had been kept under captive conditions for nine years. Lack of appetite and activity, and constipation were observed. The monkey was given fiber-rich vegetables and wild plants, and its appetite and activity then improved. Based on a consideration of various factors, it is suggested that one possible cause of the diverticulosis in this case was a low dietary fiber intake.  相似文献   
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The occurrence of accidental mutations or deletions caused by genome editing with CRISPR/Cas9 system remains a critical unsolved problem of the technology. Blocking excess or prolonged Cas9 activity in cells is considered as one means of solving this problem. Here, we report the development of an inhibitory DNA aptamer against Cas9 by means of in vitro selection (systematic evolution of ligands by exponential enrichment) and subsequent screening with an in vitro cleavage assay. The inhibitory aptamer could bind to Cas9 at low nanomolar affinity and partially form a duplex with CRISPR RNA, contributing to its inhibitory activity. We also demonstrated that improving the inhibitory aptamer with locked nucleic acids efficiently suppressed Cas9-directed genome editing in cells and reduced off-target genome editing. The findings presented here might enable the development of safer and controllable genome editing for biomedical research and gene therapy.  相似文献   
64.
Septins, a conserved family of GTP/GDP-binding proteins, are present in organisms as diverse as yeast and mammals. We analyzed the distribution of five septins, Sept6, Sept7, Sept8, Sept9 and Sept11, in various rat tissues by western blot analyses and found all septins to be expressed in brain. We also examined the developmental changes of expression of these septins in the rat brain and found that the level of Sept8 increased during post-natal development. Morphological analyses revealed that Sept8 is enriched at pre-synapses. Using yeast two-hybrid screening, we identified vesicle-associated membrane protein 2 (VAMP2), a soluble N -ethylmaleimide-sensitive factor attachment protein receptor (SNARE), as an interacting protein for Sept8. Synaptophysin is reported to associate with and recruit VAMP2 to synaptic vesicles and dissociate prior to forming the SNARE complex consisting of VAMP2, syntaxin and synaptosome-associated protein of 25 kDa. We showed that Sept8 suppresses the interaction between VAMP2 and synaptophysin through binding to VAMP2. In addition, we found that Sept8 forms a complex with syntaxin1A, and the Sept8-VAMP2 interaction is disrupted by synaptosome-associated protein of 25 kDa. These results suggest that Sept8 may participate in the process of the SNARE complex formation and subsequent neurotransmitter release.  相似文献   
65.
BACKGROUND: Many fibroblast growth factor family proteins (FGFs) bind to the heparan sulfate/heparin (HP) subtypes of sulfated glycosaminoglycans (GAGs), and a few have recently been reported to also interact with chondroitin sulfate (CS), another sulfated GAG subtype. METHODS: To gain additional insight into this interaction, we prepared all currently known FGFs (i.e., FGF1-FGF23) and assessed their affinity for HP, CS-B, CS-D and CS-E. In addition, midkine, hepatocyte growth factor and pleiotrophin were studied as other known HP-binding proteins. RESULTS: We found that members of the FGF19 subfamily (i.e., FGF15, 19, 21 and 23) had little or no affinity for HP; all of the other secretable growth factors tested had strong affinities for HP, as was indicated by the finding that their elution from HP-Sepharose columns required 1.0-1.5 M NaCl. We also found that FGF3, 6, 8 and 22 had strong affinities for CS-E, while FGF5 had a moderate affinity for CS-D. The interactions between FGFs and GAGs thus appear to be more diverse than previously understood. GENERAL SIGNIFICANCE: This is noteworthy, as the differential interactions of these growth factors with GAGs may be key determinants of their specific biological activities.  相似文献   
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Metagenomic analyses of viruses have revealed widespread diversity in the viriosphere, but it remains a challenge to identify specific hosts for a viral assemblage. To address this problem, we analyze the viral metagenome of a northeast Pacific hydrothermal vent with a comprehensive database of spacers derived from the clustered regularly interspaced short palindromic repeat (CRISPR) putative immune system. CRISPR spacer matches to the marine vent virome suggest that viruses infecting hosts from diverse taxonomic groups are present in this vent environment. Comparative virome analyses show that CRISPR spacers from vent isolates and from thermophiles in general have a higher percentage of matches to the vent virome than to other marine or terrestrial hot spring viromes. However, a high percentage of hits to spacers from mesophilic hosts, combined with a moderately high modeled alpha diversity, suggest that the marine vent virome is comprised of viruses that have the potential to infect diverse taxonomic groups of multiple thermal regimes in both the bacterial and the archaeal domains.  相似文献   
68.
26RFa and QRFP are endogenous ligands of GPR103. 26RFa binding sites are widely distributed in the brain and the spinal cord where they are involved in processing pain. In the present study, the effects of intrathecal and intracerebroventricular applications of 26RFa on the level of mechanical allodynia induced by partial sciatic nerve ligation were examined in rats. The level of mechanical allodynia was measured using von Frey filaments. Intrathecal and intracerebroventricular injection of 26RFa attenuated the level of mechanical allodynia. 26RFa has been reported to activate not only GPR103 but also neuropeptide FF2 receptor and the effect of intrathecally and intracerebroventricularly administered 26RFa was not antagonized by BIBP3226, an antagonist of neuropeptide FF receptor. Immunohistochemical examination revealed that QRFP-like immunoreactivity (QRFP-LI) was expressed mainly in the small to medium sized neurons in the L5 dorsal root ganglion (DRG) and that partial sciatic nerve injury increased the percentage of QRFP-LI positive neurons. 7 days after the nerve injury, QRFP-LI positive neurons in the L5 DRG ipsilateral to the partial sciatic nerve injury were larger than those in the L5 DRG ipsilateral to the sham operation. These data suggest that (1) exogenously applied 26RFa modulates nociceptive transmission at the spinal and the supraspinal brain in the neuropathic pain model, (2) the mechanism 26RFa uses to produce an anti-allodynic effect may be mediated by the activation of GPR103, and (3) partial sciatic nerve ligation affects the expression of QRFP-LI in the dorsal root ganglion.  相似文献   
69.

Key message

RNAi-mediated suppression of the endogenous storage proteins in MucoRice-CTB-RNAi seeds affects not only the levels of overexpressed CTB and RAG2 allergen, but also the localization of CTB and RAG2.

Abstract

A purification-free rice-based oral cholera vaccine (MucoRice-CTB) was previously developed by our laboratories using a cholera toxin B-subunit (CTB) overexpression system. Recently, an advanced version of MucoRice-CTB was developed (MucoRice-CTB-RNAi) through the use of RNAi to suppress the production of the endogenous storage proteins 13-kDa prolamin and glutelin, so as to increase CTB expression. The level of the α-amylase/trypsin inhibitor-like protein RAG2 (a major rice allergen) was reduced in MucoRice-CTB-RNAi seeds in comparison with wild-type (WT) rice. To investigate whether RNAi-mediated suppression of storage proteins affects the localization of overexpressed CTB and major rice allergens, we generated an RNAi line without CTB (MucoRice-RNAi) and investigated gene expression, and protein production and localization of two storage proteins, CTB, and five major allergens in MucoRice-CTB, MucoRice-CTB-RNAi, MucoRice-RNAi, and WT rice. In all lines, glyoxalase I was detected in the cytoplasm, and 52- and 63-kDa globulin-like proteins were found in the aleurone particles. In WT, RAG2 and 19-kDa globulin were localized mainly in protein bodies II (PB-II) of the endosperm cells. Knockdown of glutelin A led to a partial destruction of PB-II and was accompanied by RAG2 relocation to the plasma membrane/cell wall and cytoplasm. In MucoRice-CTB, CTB was localized in the cytoplasm and PB-II. In MucoRice-CTB-RNAi, CTB was produced at a level six times that in MucoRice-CTB and was localized, similar to RAG2, in the plasma membrane/cell wall and cytoplasm. Our findings indicate that the relocation of CTB in MucoRice-CTB-RNAi may contribute to down-regulation of RAG2.  相似文献   
70.
Sphingosine-1-phosphate (S1P) is a biologically active sphingolipid that acts through the members of a family of five G protein-coupled receptors (S1P1–S1P5). S1P1 is a major regulator of lymphocyte trafficking, and fingolimod, whose active metabolite fingolimod phosphate acts as a nonselective S1P receptor agonist, exerts its immunomodulatory effect, at least in part, by regulating the lymphocyte trafficking by inducing down regulation of lymphocyte S1P1. Here, we detail the pharmacological profile of 5-{5-[3-(trifluoromethyl)-4-{[(2S)-1,1,1-trifluoropropan-2-yl]oxy}phenyl]-1,2,4-oxadiazol-3-yl}-1H-benzimidazole (ASP4058), a novel next-generation S1P receptor agonist selective for S1P1 and S1P5. ASP4058 preferentially activates S1P1 and S1P5 compared with S1P2, 3, 4 in GTPγS binding assays in vitro. Oral administration of ASP4058 reduced the number of peripheral lymphocytes and inhibited the development of experimental autoimmune encephalomyelitis (EAE) in Lewis rats. Further, ASP4058 prevented relapse of disease in a mouse model of relapsing-remitting EAE. Although these immunomodulatory effects were comparable to those of fingolimod, ASP4058 showed a wider safety margin than fingolimod for bradycardia and bronchoconstriction in rodents. These observations suggest that ASP4058 represents a new therapeutic option for treating multiple sclerosis that is safer than nonselective S1P receptor agonists such as fingolimod.  相似文献   
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