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911.
Length–weight relationships were determined in 39 muraenid species belonging to seven genera collected during 2003–2008 from the waters around Taiwan. Various fishing methods were used to collect both the adult and pre‐adult moray eel specimens. Length–weight relationship records of 28 species are provided for the first time. New maximum size records of six species were also established: 61.2 cm for Gymnothorax monostigma, 88.2 cm for G. niphostigmus, 68.6 cm for G. shaoi, 53.9 cm for G. taiwanensis, 73.2 cm for G. thyrsoideus, and 37.3 cm for U. micropterus.  相似文献   
912.
Skin injury evokes both innate and adaptive immune responses to restore tissue integrity. TLRs play a critical role in host responses to injurious insults. Previous studies demonstrated that RNAs released from damaged tissues served as endogenous ligands for TLR3. In this study, we investigated the involvement of TLR3 in skin restoration after injury. Full excisional wounds were created on the skin of mice with TLR3 deficiency. We found that skin wound closure in TLR3(-/-) mice was significantly delayed compared with control littermates. Wound healing parameters, including re-epithelialization, granulation formation, and neovascularization, were decreased in TLR3(-/-) mice. Further studies revealed that the absence of TLR3 led to defective recruitment of neutrophils and macrophages, in association with decreased expression of the chemokines, MIP-2/CXCL2, MIP-1α/CCL3, and MCP-1/CCL2, in the wound. Moreover, in wild type mice, the mRNA level and protein content of TLR3 was significantly upregulated in wounded skins and silencing of TLR3 signal adaptor Toll/IL-1R domain-containing adapter inducing IFN-β with small interfering RNA retarded wound closure. These results indicate an essential role for TLR3 and Toll/IL-1R domain-containing adapter inducing IFN-β in wound healing by regulating chemokine production and recruitment of myeloid cells to wound for tissue repair.  相似文献   
913.
Species of Lophiidae collected from the western South Pacific Ocean are examined. Nine nominal species are recognized, all but one species with their distributions extended eastwards and southwards from the western Pacific Ocean. Two new species are described from Polynesia. Lophiodes iwamotoi n. sp. is described from five specimens collected from Savannah Seamount. It is characterized by a relatively long third dorsal-fin spine (56.9-70.8% standard length, L(S)) that extends (when retracted) to between the end of the soft dorsal fin and caudal-fin base; a relatively short fifth dorsal-fin spine (10.5-13.1% L(S)); a relatively short and narrow head; 19-20 pectoral-fin rays. Lophiodes maculatus n. sp. is described from 20 specimens collected from Marquesas Islands. It is characterized by an extremely long third dorsal-fin spine (71.9-87.2% L(S)), extending well beyond the caudal-fin base; a relatively short fifth dorsal-fin spine (11.4-16.5% L(S)); 17-18 pectoral-fin rays. A key to the lophiids in the western South Pacific Ocean is provided.  相似文献   
914.
Herpes simplex virus 1 (HSV-1) capsids leave the nucleus by a process of envelopment and de-envelopment at the nuclear envelope (NE) that is accompanied by structural alterations of the NE. As capsids translocate across the NE, transient primary enveloped virions form in the perinuclear space. Here, we provide evidence that torsinA (TA), a ubiquitously expressed ATPase, has a role in HSV-1 nuclear egress. TA resides within the lumen of the endoplasmic reticulum (ER)/NE and functions in maintaining normal NE architecture. We show that perturbation of TA normal function by overexpressing torsinA wild type (TAwt) inhibits HSV-1 production. Ultrastructural analysis of infected cells overexpressing TAwt revealed reduced levels of surface virions in addition to accumulation of novel, double-membrane structures called virus-like vesicles (VLVs). Although mainly found in the cytoplasm, VLVs resemble primary virions in their size, by the appearance of the inner membrane, and by the presence of pUL34, a structural component of primary virions. Collectively, our data suggest a model in which interference of TA normal function by overexpression impairs de-envelopment of the primary virions leading to their accumulation in a cytoplasmic membrane compartment. This implies novel functions for TA at the NE.  相似文献   
915.
Liu L  Wen M  Wang W  Wang S  Yang L  Liu Y  Qian M  Zhang L  Shao Y  Kimata JT  Zhou P 《Journal of virology》2011,85(17):8467-8476
PG9 and PG16 are two recently isolated quaternary-specific human monoclonal antibodies that neutralize 70 to 80% of circulating HIV-1 isolates. The crystal structure of PG16 shows that it contains an exceptionally long CDR H3 that forms a unique stable subdomain that towers above the antibody surface to confer fine specificity. To determine whether this unique architecture of CDR H3 itself is sufficient for epitope recognition and neutralization, we cloned CDR H3 subdomains derived from human monoclonal antibodies PG16, PG9, b12, E51, and AVF and genetically linked them to a glycosyl-phosphatidylinositol (GPI) attachment signal. Each fusion gene construct is expressed and targeted to lipid rafts of plasma membranes through a GPI anchor. Moreover, GPI-CDR H3(PG16, PG9, and E51), but not GPI-CDR H3(b12 and AVF), specifically neutralized multiple clades of HIV-1 isolates with a great degree of potency when expressed on the surface of transduced TZM-bl cells. Furthermore, GPI-anchored CDR H3(PG16), but not GPI-anchored CDR H3(AVF), specifically confers resistance to HIV-1 infection when expressed on the surface of transduced human CD4(+) T cells. Finally, the CDR H3 mutations (Y100HF, D100IA, and G7) that were previously shown to compromise the neutralization activity of antibody PG16 also abolished the neutralization activity of GPI-CDR H3(PG16). Thus, we conclude that the CDR H3 subdomain of PG16 neutralizes HIV-1 when targeted to the lipid raft of the plasma membrane of HIV-1-susceptible cells and that GPI-CDR H3 can be an alternative approach for determining whether the CDR H3 of certain antibodies alone can exert epitope recognition and neutralization.  相似文献   
916.
917.
Methylation and demethylation of DNA are the complementary processes of epigenetic regulation. These two types of regulation influence a diverse array of cellular activities, including the maintenance of pluripotency and self-renewal in embryonic stem cells. It was generally believed that DNA demethylation occurs passively over several cycles of DNA replication and that active DNA demethylation is rare. Recently, evidence for active DNA demethylation has been obtained in several cancer, neuronal, and embryonic stem cell lines. Studies in embryonic stem cell models, however, suggested that active DNA demethylation might be restricted to the early development of progenitor cells. Whether active demethylation is involved in terminal differentiation of adult stem cells is poorly understood. We provide evidence that active DNA demethylation does occur during terminal specification of stem cells in an adipose-derived mesenchymal stem cell-derived osteogenic differentiation model. The medium CpG regions in promoters of the Dlx5, Runx2, Bglap, and Osterix osteogenic lineage-specific genes were demethylated during the increase in gene expression associated with osteogenic differentiation. The growth arrest and DNA damage-inducible protein GADD45A was up-regulated in these processes. Knockdown of GADD45A led to hypermethylation of Dlx5, Runx2, Bglap, and Osterix promoters, followed by suppression of the expression of these genes and interruption of osteogenic differentiation. These results reveal that GADD45A plays an essential role in gene-specific active DNA demethylation during adult stem cell differentiation. They enhance the current knowledge of osteogenic specification and may also lead to a better understanding of the common mechanisms underlying epigenetic regulation in adult stem cell differentiation.  相似文献   
918.
During cell division, interaction between kinetochores and dynamic spindle microtubules governs chromosome movements. The microtubule depolymerase mitotic centromere-associated kinesin (MCAK) is a key regulator of mitotic spindle assembly and dynamics. However, the regulatory mechanisms underlying its depolymerase activity during the cell cycle remain elusive. Here, we showed that PLK1 is a novel regulator of MCAK in mammalian cells. MCAK interacts with PLK1 in vitro and in vivo. The neck and motor domain of MCAK associates with the kinase domain of PLK1. MCAK is a novel substrate of PLK1, and the phosphorylation stimulates its microtubule depolymerization activity of MCAK in vivo. Overexpression of a polo-like kinase 1 phosphomimetic mutant MCAK causes a dramatic increase in misaligned chromosomes and in multipolar spindles in mitotic cells, whereas overexpression of a nonphosphorylatable MCAK mutant results in aberrant anaphase with sister chromatid bridges, suggesting that precise regulation of the MCAK activity by PLK1 phosphorylation is critical for proper microtubule dynamics and essential for the faithful chromosome segregation. We reasoned that dynamic regulation of MCAK phosphorylation by PLK1 is required to orchestrate faithful cell division, whereas the high levels of PLK1 and MCAK activities seen in cancer cells may account for a mechanism underlying the pathogenesis of genomic instability.  相似文献   
919.
920.
Habenula--a new target for treatment of intractable depression   总被引:1,自引:0,他引:1  
Wang S 《生理科学进展》2011,42(6):407-412
Despite substantial advancement in psychopharmacological and electro-magnetic treatments over the last decades on the depression patients, there are non-responders remain with a chronic disease and high suicidal risk yet. Deep brain stimulation (DBS) is now being experimentally to treat the intractable depression and yielded an impressive therapeutic benefit, and especially few adverse effect occurred. The beneficial action of DBS is closely related to the stimulation sit. And the efficacy of high frequency stimulation of lateral habenula is one of the best choice. In depression, the concentration of 5-HT released by the raphe nuclei is decreased. It's due to mainly the overactivation of the lateral habenula. High frequency stimulation of lateral habenula impairs the activation of lateral habenula, and the inhibitory effect of lateral habenula on raphe nuclei is decreased. Then, the 5-HT concentration released by the raphe nuclei is increased, the pathological changes of depression is eliminated. The lateral habenula could be a promising novel target for BDS in the cases of intractable depression.  相似文献   
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