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81.
To achieve the potent therapeutic effects of human immunoglobulin G (IgG), highly concentrated formulations are required. However, the stabilization for highly concentrated human IgG is laborious work. In the present study, to investigate the potentials of polypseudorotaxane (PPRX) hydrogels consisting of polyethylene glycol (PEG) and α- or γ-cyclodextrin (α- or γ-CyD) as pharmaceutical materials for highly concentrated human IgG, we designed the PPRX hydrogels including human IgG and evaluated their pharmaceutical properties. The α- and γ-CyDs formed PPRX hydrogels with PEG (M.W. 20,000) even in the presence of highly concentrated human IgG (>100 mg/mL). According to the results of 1H-NMR, powder X-ray diffraction, and Raman microscopy, the formation of human IgG/CyD PPRX hydrogels was based on physical cross-linking arising from their columnar structures. The release profiles of human IgG from the hydrogels were in accordance with the non-Fickian diffusion model. Importantly, the stabilities of human IgG included into the hydrogels against thermal and shaking stresses were markedly improved. These findings suggest that PEG/CyD PPRX hydrogels are useful to prepare the formulation for highly concentrated human IgG.KEY WORDS: cyclodextrin, human IgG, hydrogel, polypseudorotaxane, stability  相似文献   
82.
The newly characterized cytokine IL-38 (IL-1F10) belongs to the IL-1 family of cytokines. Previous work has demonstrated that IL-38 inhibited Candida albicans-induced IL-17 production from peripheral blood mononuclear cells. However, it is still unclear whether IL-38 is an inflammatory or an anti-inflammatory cytokine. We generated anti-human IL-38 monoclonal antibodies in order to perform immunohistochemical staining and an enzyme-linked immunosorbent assay. While human recombinant IL-38 protein was not cleaved by recombinant caspase-1, chymase, or PR3 in vitro, overexpression of IL-38 cDNA produced a soluble form of IL-38 protein. Furthermore, immunohistochemical analysis showed that synovial tissues obtained from RA patients strongly expressed IL-38 protein. To investigate the biological role of IL-38, C57BL/6 IL-38 gene-deficient (?/?) mice were used in an autoantibody-induced rheumatoid arthritis (RA) mouse model. As compared with control mice, IL-38 (?/?) mice showed greater disease severity, accompanied by higher IL-1β and IL-6 gene expression in the joints. Therefore, IL-38 acts as an inhibitor of the pathogenesis of autoantibody-induced arthritis in mice and may have a role in the development or progression of RA in humans.  相似文献   
83.
Long noncoding RNAs (lncRNAs) are vastly transcribed and extensively studied but lncRNAs overlapping with the sense orientation of mRNA have been poorly studied. We analyzed the lncRNA DAPALR overlapping with the 5´ UTR of the Doublesex1 (Dsx1), the male determining gene in Daphnia magna. By affinity purification, we identified an RNA binding protein, Shep as a DAPALR binding protein. Shep also binds to Dsx1 5´ UTR by recognizing the overlapping sequence and suppresses translation of the mRNA. In vitro and in vivo analyses indicated that DAPALR increased Dsx1 translation efficiency by sequestration of Shep. This regulation was impaired when the Shep binding site in DAPALR was deleted. These results suggest that Shep suppresses the unintentional translation of Dsx1 by setting a threshold; and when the sense lncRNA DAPALR is expressed, DAPALR cancels the suppression caused by Shep. This mechanism may be important to show dimorphic gene expressions such as sex determination and it may account for the binary expression in various developmental processes.  相似文献   
84.
The fungus Beauveria bassiana (Balsamo) Vuillemin has previously been classified using morphological characteristics, but morphology cannot reveal the phylogenetic relationships among conventionally classified strains. High levels of homology have been found in gene sequences among various B. bassiana strains, complicating the determination of their evolutionary relationships. To elucidate phylogenetic relationships among conventionally known Beauveria species, we analyzed 57 major strains of B. bassiana and 3 strains of B. brongniartii (Saccardo) Petch isolated from Japan by analysis of internal transcribed spacer (ITS) sequences and genome profiling (GP) based on temperature gradient gel electrophoresis of random PCR products. The ITS sequence analysis placed the 57 conventional B. bassiana strains into two clusters, B. bassiana and Beauveria pseudobassiana Rehner et Humber. In contrast, GP analysis produced five clusters of B. bassiana strains that included B. pseudobassiana clusters. These results suggested that GP was more accurate than ITS sequence analysis for determining phylogenetic relationships within B. bassiana. In addition, our findings suggested that conventional strains of B. bassiana isolated from Japan include both B. bassiana and B. pseudobassiana groups.  相似文献   
85.
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   
86.
To understand the role of prostaglandin (PG) receptor EP2 (Ptger2) signaling in ovulation and fertilization, we investigated time-dependent expression profiles in wild-type (WT) and Ptger2−/− cumuli before and after ovulation by using microarrays. We prepared cumulus cells from mice just before and 3, 9 and 14 h after human chorionic gonadotropin injection. Key genes including cAMP-related and epidermal growth factor (EGF) genes, as well as extracellular matrix- (ECM-) related and chemokine genes were up-regulated in WT cumuli at 3 h and 14 h, respectively. Ptger2 deficiency differently affected the expression of many of the key genes at 3 h and 14 h. These results indicate that the gene expression profile of cumulus cells greatly differs before and after ovulation, and in each situation, PGE2-EP2 signaling plays a critical role in cAMP-regulated gene expression in the cumulus cells under physiological conditions.  相似文献   
87.
88.
Background: The treatment and prevention of glucocorticoid (GC)-induced osteoporosis have been controversial in premenopausal women during their childbearing years.Objective: This study assessed the incidence and risk factors for symptomatic vertebral fracture in women of childbearing age newly treated with high-dose GC.Methods: An observational cohort study was conducted at the rheumatic center of Shimoshizu National Hospital in Chiba, Japan, from 1986 to 2006. The prevalence of symptomatic vertebral fractures, as determined by x-rays, was assessed in premenopausal (aged <50 years) women with collagen vascular disease newly treated with high-dose GC (≥20 mg/d prednisolone equivalent) compared with their counterparts who did not receive GC. Differences in the incidences of vertebral fractures were compared between groups by the Kaplan-Meier method and evaluated by the log-rank test. Hazard ratios (HRs) with 95% CIs were estimated using the Cox proportional hazards regression model.Results: A total of 373 women were assessed: 292 patients in the high-dose GC treatment group (mean [SD] initial age, 32.4 [8.2] years; initial dose, 43.8 [14.9] mg/d; follow-up time, 124.2 [75.4] months) and 81 patients in the non-GC control group (initial age, 39.3 [7.8] years; follow-up time, 106.5 [79.7] months). Symptomatic vertebral fractures occurred more frequently in the high-dose GC group (11.3%) than in the non-GC group (1.2%). Using the Cox model, the adjusted HR for the high-dose GC group was 13.96 (95% CI, 1.87–104.22) relative to the non-GC group. In the high-dose GC group, Kaplan-Meier analyses revealed that the incidence of fractures in women in their forties was significantly higher in comparison with those in their twenties (P < 0.001) and thirties (P < 0.05), and that the incidence of fractures in those who consumed alcohol (>80 g/wk of pure alcohol) was significantly higher than in those who did not (P < 0.05). The Cox model also revealed that the risk was independently higher with every 10-year increment of initial age (HR = 2.27; 95% CI, 1.46–3.53), with every GC dose increase (HR = 2.28; 95% CI, 1.58–3.31), and with each 1-gram decrease of cumulative GC dose (HR = 0.95; 95% CI, 0.93–0.98).Conclusions: In this study, high-dose GC use was associated with a significantly high prevalence of symptomatic vertebral fractures in premenopausal women with collagen vascular disease during their childbearing years. However, the fracture risk was relatively low in women of childbearing age, especially those in their twenties and thirties during the early years of treatment.  相似文献   
89.
Little is known about how synaptic activity is modulated in the central nervous system. We have identified SCRAPPER, a synapse-localized E3 ubiquitin ligase, which regulates neural transmission. SCRAPPER directly binds and ubiquitinates RIM1, a modulator of presynaptic plasticity. In neurons from Scrapper-knockout (SCR-KO) mice, RIM1 had a longer half-life with significant reduction in ubiquitination, indicating that SCRAPPER is the predominant ubiquitin ligase that mediates RIM1 degradation. As anticipated in a RIM1 degradation defect mutant, SCR-KO mice displayed altered electrophysiological synaptic activity, i.e., increased frequency of miniature excitatory postsynaptic currents. This phenotype of SCR-KO mice was phenocopied by RIM1 overexpression and could be rescued by re-expression of SCRAPPER or knockdown of RIM1. The acute effects of proteasome inhibitors, such as upregulation of RIM1 and the release probability, were blocked by the impairment of SCRAPPER. Thus, SCRAPPER has an essential function in regulating proteasome-mediated degradation of RIM1 required for synaptic tuning.  相似文献   
90.
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