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111.
The time-dependent effects of daily dosing of IGF-I (1.21 mg/g) on the linear growth of the femur were investigated in mice. The femoral length and volume and the number of osteoclasts were significantly greater after IGF-I injection as compared to the non-injected control, suggesting that the IGF-I imbalance might cause a quick turnover cycle of the bone resulting in the altered femoral modeling.  相似文献   
112.
Distribution of the freshwater fishes of Japan: an historical overview   总被引:2,自引:0,他引:2  
Japanese freshwater fishes, including lampreys, comprise 15 orders, 35 families, and 96 genera, with 211 species and subspecies. Most belong to the families Cyprinidae (29% of species and subspecies), Gobiidae (21%), Salmonidae (10%), and Cobitidae (8%). Cyprinids and cobitids presumably originated from east Asia, gobiids from southeast Asia, and cottids and salmonids from the north Pacific. Japanese freshwater fishes include 88 endemic species and subspecies, of which three have been extirpated. Fishes introduced into natural rivers and lakes for inland commercial fisheries and sport fishing, and by accident, include many exotic species, of which 23 now inhabit natural freshwaters. These often have destroyed the local fish fauna by predation, and caused genetic pollution by hybridization with local strains. Destruction of freshwater environments by land development also poses a threat to Japanese freshwater fish communities. In addition Japanese freshwater systems have been markedly altered by development of rice paddy fields which have caused some species to decline but others to flourish, and changed the distribution patterns of fishes between upstream and downstream areas. To conserve endangered species and declining communities of Japanese freshwater fishes, we need to clarify the characteristics of their original habitats and the effects of developing paddy fields, from both the ecological and historical points of view.  相似文献   
113.
We present 3 adult cases of visceral toxocariasis from the same family, who each consumed thin slices of raw bovine liver weekly, and developed eosinophilia and multiple small lesions in their livers and lungs. Serological examinations using the larval excretory–secretory product of Toxocara canis strongly indicated infection with Toxocara species larvae. The patients responded well to treatment with albendazole. Ingestion of raw liver from paratenic animals is considered to be a common transmission route of human toxocariasis, especially in adults.  相似文献   
114.
The serine/threonine protein kinase Akt is involved in a variety of cellular processes including cell proliferation, survival, metabolism and gene expression. It is essential in vascular endothelial growth factor (VEGF)-mediated angiogenesis; however, it is not known how Akt regulates the migration of endothelial cells, a crucial process for vessel sprouting, branching and the formation of networks during angiogenesis. Here we report that Akt-mediated phosphorylation of Girdin, an actin-binding protein, promotes VEGF-dependent migration of endothelial cells and tube formation by these cells. We found that exogenously delivered adenovirus harbouring Girdin short interfering RNA in Matrigel embedded in mice, markedly inhibited VEGF-mediated angiogenesis. Targeted disruption of the Girdin gene in mice impaired vessel remodelling in the retina and angiogenesis from aortic rings, whereas Girdin was dispensable for embryonic vasculogenesis. These findings demonstrate that the Akt/Girdin signalling pathway is essential in VEGF-mediated postneonatal angiogenesis.  相似文献   
115.
Aim: Inorganic polyphosphate exists as chains of phosphate molecules and is distributed in osteoblasts, and regulates osteoblastic cell differentiation and bone matrix calcification. The purpose of this study was to clarify the effects of inorganic polyphosphate on periodontitis. Material and methods: Subgingival local irrigation with inorganic polyphosphate was studied in a randomised double‐blind study of 33 patients with periodontitis. Scaling and root planing were performed 1 week after the initial examination. Results: No significant differences between the inorganic polyphosphate group and control were detected in each item except IL‐1β. Patients in whom both the bleeding on probing and gingival index at 1 week had improved were significantly older in the inorganic polyphosphate group than in the control group (p < 0.05). Bone regeneration was seen in one case of the inorganic polyphosphate group. Conclusions: Inorganic polyphosphate was useful in the treatment of periodontitis in the elderly, indicating a probable effect of anti‐ageing, with similar bone regenerations occurring in both groups.  相似文献   
116.
The number of peroxisomes in a cell can change rapidly in response to changing environmental and physiological conditions. Pexophagy, a type of selective autophagy, is involved in peroxisome degradation, but its physiological role remains to be clarified. Here, we report that cells of the cucumber anthracnose fungus Colletotrichum orbiculare undergo peroxisome degradation as they infect host plants. We performed a random insertional mutagenesis screen to identify genes involved in cucumber pathogenesis by C. orbiculare. In this screen, we isolated a homolog of Pichia pastoris ATG26, which encodes a sterol glucosyltransferase that enhances pexophagy in this methylotrophic yeast. The C. orbiculare atg26 mutant developed appressoria but exhibited a specific defect in the subsequent host invasion step, implying a relationship between pexophagy and fungal phytopathogenicity. Consistent with this, its peroxisomes are degraded inside vacuoles, accompanied by the formation of autophagosomes during infection-related morphogenesis. The autophagic degradation of peroxisomes was significantly delayed in the appressoria of the atg26 mutant. Functional domain analysis of Atg26 suggested that both the phosphoinositide binding domain and the catalytic domain are required for pexophagy and pathogenicity. In contrast with the atg26 mutant, which is able to form appressoria, the atg8 mutant, which is defective in the entire autophagic pathway, cannot form normal appressoria in the earlier steps of morphogenesis. These results indicate a specific function for Atg26-enhanced pexophagy during host invasion by C. orbiculare.  相似文献   
117.
AimsThe aim of this study was to investigate the significance of epidermal growth factor receptor (EGFR) ligands produced in syncytiotrophoblasts during normal pregnancy.Main methodsWe examined the expression of EGFR ligands in human pregnancy by real-time PCR, and analyzed the relationship between EGFR ligands and human chorionic gonadotropin (hCG) or human placental lactogen in amniotic fluid by ELISA. In addition, we also examined the EGFR ligands in syncytiotrophoblasts and the amount of hCG secretion in JAR, JEG3 and BeWo cells in the presence of each EGFR ligand.Key findingsIn order to identify possible candidates among the EGFR ligands, we examined the predominant expression of an EGFR ligand in the chorionic villi and amniotic fluid during normal pregnancy, and analyzed the relationship between EGFR ligands and hCG in trophoblastic model cells. Amphiregulin was primarily expressed throughout human pregnancy and stimulated the secretion of hCG, indicating that amphiregulin is a key molecule among EGFR ligands.SignificanceAmphiregulin may play a pivotal role in the development or maturation of placenta.  相似文献   
118.
We have characterized the structural and molecular interactions of CC-chemokine receptor 5 (CCR5) with three CCR5 inhibitors active against R5 human immunodeficiency virus type 1 (HIV-1) including the potent in vitro and in vivo CCR5 inhibitor aplaviroc (AVC). The data obtained with saturation binding assays and structural analyses delineated the key interactions responsible for the binding of CCR5 inhibitors with CCR5 and illustrated that their binding site is located in a predominantly lipophilic pocket in the interface of extracellular loops and within the upper transmembrane (TM) domain of CCR5. Mutations in the CCR5 binding sites of AVC decreased gp120 binding to CCR5 and the susceptibility to HIV-1 infection, although mutations in TM4 and TM5 that also decreased gp120 binding and HIV-1 infectivity had less effects on the binding of CC-chemokines, suggesting that CCR5 inhibition targeting appropriate regions might render the inhibition highly HIV-1-specific while preserving the CC chemokine-CCR5 interactions. The present data delineating residue by residue interactions of CCR5 with CCR5 inhibitors should not only help design more potent and more HIV-1-specific CCR5 inhibitors, but also give new insights into the dynamics of CC-chemokine-CCR5 interactions and the mechanisms of CCR5 involvement in the process of cellular entry of HIV-1.  相似文献   
119.
A preceding paper suggested 81 candidates of stage-specifically expressed proteins for either stage IA or IIIA by global shotgun proteomics and spectral counting. Six proteins, a subset of these proteins, were chosen for a further verification study since they are potentially soluble and/or secretory, which nature is convenient for detecting them in blood in clinical practice. The multiple-reaction monitoring (MRM) quantitative analysis suggested that napsin-A and anterior gradient protein 2 homolog (hAG-2) out of the 6 candidates would be useful for determining stage IA or IIIA and are related to metastasis. In the study we noted that stage IIIA patients with better outcome showed napsin-A profiles similar to that of stage IA patients. We therefore examined 14 additional patients for analysis, which contained the IA-stage patients of poorer outcome and the IIIA-stage patients of better outcome. The MRM analysis of napsin-A for all patients suggests that napsin-A contents correlate with better outcome in stage IA. This and discovery studies demonstrate that direct isolation of tumor cells alone by laser microdissection (LMD) greatly reduces complexity on comprehensive analyses, and that MRM mass spectrometry using the endogenous internal standard is a feasible technology for quantitative verification of target proteins in formalin-fixed paraffin embedded (FFPE) tissues.  相似文献   
120.
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