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991.
Hepatocyte growth factor (HGF) by stimulating the receptor tyrosine kinase c-Met induces angiogenesis and tissue regeneration. HGF has been shown to antagonize the angiotensin II-induced senescence of endothelial progenitor cells (EPCs), which is mediated by NADPH oxidase-dependent reactive oxygen species (ROS) formation. As growth factors, however, usually require ROS for their signaling, we hypothesized that the proangiogenic effects of HGF require NADPH oxidases and focused on the homolog Nox2, which is most abundantly expressed in EPCs and endothelial cells. Indeed, HGF increased the H(2)O(2) formation in EPCs and human umbilical vein endothelial cells (HUVECs), and this effect was not observed in Nox2-deficient cells. HGF induced the mobilization of EPCs and vascular outgrowth from aortic explants in wild-type (WT) but not Nox2(y/-) mice. HGF also stimulated migration and tube formation in HUVECs, and antisense oligonucleotides against Nox2 prevented this effect. To identify the signal transduction underlying these effects, we focused on the kinases Jak2 and Jnk. In HUVECs, HGF increased the phosphorylation of these in a Nox2-dependent manner as demonstrated by antisense oligonucleotides. Also, the HGF-induced Jak2-dependent activation of a STAT3 reporter construct was attenuated after downregulation of Nox2. Accordingly, the HGF-stimulated tube formation of HUVEC was blocked by inhibitors of Jak2 and Jnk. In vivo treatment with the Jnk inhibitor SP600125 blocked the HGF-induced mobilization of EPCs. Ex vivo, SP600125 blocked HGF-induced migration and tube formation. We conclude that HGF-induced mobilization of EPCs and the proangiogenic effects of the growth factor require a Nox2-dependent ROS-mediated activation of Jak2 and Jnk.  相似文献   
992.
Mucolipidosis type III (MLIII) is a mild form of Mucolipidosis type II (MLII, I-cell disease) of late onset, of which almost no pathological study has been reported, as it is a very rare disease. We encountered the case of a 23-year-old man of Japanese and Caucasian mixed parentage diagnosed with MLIII by enzyme assay and genotyping. He died suddenly due to severe dilated cardiomyopathy. On the day after his death, autopsy was performed, and accumulation of Luxol Fast Blue (LFB) positive material was found to be most severe in the neuronal cells of dorsal root ganglions (DRG). Electromicroscopic DRG revealed the neuronal cytoplasm was filled with a zebra-body-like membranous matrix. We tried immunohistochemistry to investigate the mechanism of such accumulation in the DRG that resulted in double positive anti-ubiquitin antibody (FK-2) and anti-LC3 antibody (as specific marker for autophagy) staining, and speculated activating of autophagosome pathway, and 'zebra-body' should be suspected as dysfunctional autophagosome. We also detected foamy cell proliferation in the dura mater, Auerbach's plexus (peripheral nervous system), podocytes of almost all glomeruli, cartilage tissue in lumbar discs, and in cardiac muscle. We tried FK-2 and anti-LC3 antibody staining also for the podocytes, the area with the most marked proliferation of foamy cells, but the result was negative. This led us to speculate that these pathological findings, namely, accumulation of LFB-positive material and foamy fibroblast proliferation, might be the forms of dysfunctional autophagosome at various stages of development. This pathological study of MLIII supports the theory that MLIII is a mild type of MLII because of the close similarity of their pathological findings.  相似文献   
993.
OBJECTIVE: The goal of this study was to use three-dimensional (3D) analysis to characterize the primary facial deformities in children with unilateral cleft lip and palate (UCLP) and then serially analyze the relationships between facial deformities and maxillofacial growth from infancy to adolescence. PARTICIPANTS: Twenty-one Japanese subjects with unilateral cleft lip and alveolus (UCLA) and 20 with UCLP who had been operated on and then followed up for more than 15 years were enrolled in this study. MAIN OUTCOME MEASURES: Facial cast models taken at cheiloplasty were scanned with a 3D laser scanner. Lateral cephalographs taken when subjects were 15 years of age or older were traced, and linear and angular measurements were calculated. The correlation between primary facial forms and maxillofacial morphology in adolescence was analyzed. RESULTS: Three-dimensional analysis showed larger ocular hypertelorism, wider cleft, greater deviation of the columella base, and more severe retruded position of the affected nasal alar base in subjects with UCLP than those with UCLA. Total surface area of the upper lips in subjects with UCLP was significantly smaller than those with UCLA. Correlation analyses revealed that the width of cleft lip, deviation of the columella base, difference of the nose base width, and surface area of the upper lip were statistically correlated with the maxillary length, the anterior position of the maxillary alveolar base, the posterior facial height, and the high angle of the mandible. CONCLUSION: The subjects who had less severe facial deformities and more tissue volume of the upper lips at cheiloplasty showed better maxillofacial growth.  相似文献   
994.
995.
Background and aimsPeripheral artery disease (PAD), intermittent claudication, and impaired mobility contribute to the loss of skeletal muscle. This study investigated the impact of endovascular treatment (EVT) in patients suffering from PAD above the knee and its relation to baseline glycemic control.Methods and resultsMid-thigh muscle volume was measured before EVT, 3 months after EVT and 6 months after EVT. Mid-thigh muscle volumes of ipsilateral PAD patients with ischemic and non-ischemic legs were compared. Correlations between total thigh muscle volume and clinical characteristics were analyzed using univariable and multivariable analysis. Overall, thigh muscle volume increased after EVT. The mid-thigh muscle volume was significantly lower in patients with ipsilateral lesions and in those with ischemic lower limbs. The thigh muscle volume of those with ischemic lower limbs increased after EVT. Baseline glycated hemoglobin was the only factor that was negatively correlated with changes in the muscle volume after EVT. Muscle volume significantly increased in normoglycemic HbA1c<6.5% (47 mmol/mol) patients. There was no significant alteration in the muscle volume of hyperglycemic HbA1c ≥ 6.5% patients.ConclusionIschemic muscle atrophy was ameliorated after EVT in normoglycemic patients. There is a need for a large-scale trial to investigate whether EVT can protect or delay skeletal muscle loss.  相似文献   
996.
The active involvement of hospital laboratory in surveillance is crucial to the success of nosocomial infection control. The recent dramatic increase of antimicrobial-resistant organisms and their spread into the community suggest that the infection control strategy of independent medical institutions is insufficient. To share the clinical data and surveillance in our local medical region, we developed a microbiology data warehouse for networking hospital laboratories in Akita prefecture. This system, named Akita-ReNICS, is an easy-to-use information management system designed to compare, track, and report the occurrence of antimicrobial-resistant organisms. Participating laboratories routinely transfer their coded and formatted microbiology data to ReNICS server located at Akita University Hospital from their health care system's clinical computer applications over the internet. We established the system to automate the statistical processes, so that the participants can access the server to monitor graphical data in the manner they prefer, using their own computer's browser. Furthermore, our system also provides the documents server, microbiology and antimicrobiotic database, and space for long-term storage of microbiological samples. Akita-ReNICS could be a next generation network for quality improvement of infection control.  相似文献   
997.
The present study investigates the anti-oxidative effects of D-allose on ischemic damage. Rats were subjected to transient middle cerebral artery occlusion (MCAO) for 1 h under pentobarbital anesthesia. D-allose was intravenously infused during occlusion and a further 1 h after reperfusion (400 mg/kg). The effects of D-allose on focal cerebral ischemia were examined by measuring brain damage (infarction and atrophy volume) and behavioral deficits 7 days after MCAO. In another set of rats, apurnic/apyrimidic abasic sites (AP-sites) and 8-hydroxy-2'-deoxyguanosine (8-OHdG), oxidative stress markers, were investigated 24 h after MCAO to examine the anti-oxidative effects of D-allose. Brain damage and behavioral deficits were significantly decreased by D-allose administration compared to vehicle. The number of AP-sites and 8-OHdG levels were also reduced by D-allose. Thus, the present study suggests that D-allose has anti-oxidative effects and induces neuroprotection in focal cerebral ischemia.  相似文献   
998.
To clarify the involvement of GluR2 and GluR3 subunits of AMPA receptor in orofacial neuropathic pain, we studied changes in nocifensive behavior and extracellular-signal regulated kinase (ERK) phosphorylation followed by infraorbital nerve (ION)-partial transection model applied to GluR2 or GluR3 delta7 knock-in (KI) mice. In these animals, last seven amino acids of GluR2 or GluR3 subunit, the binding sites of interacting protein, are deleted in vivo. Head-withdrawal threshold to mechanical stimulation of the whisker pad skin ipsilateral to ION-partial transection was significantly reduced at 1, 3, 5, 7, 11 and 14 days after transection compared with that before transection in wild-type mice. In the GluR2 and GluR3 delta7 KI mice, the head-withdrawal threshold did not change following ION-partial transection. The number of pERK-LI cells examined in Vc and C1-C2 in wild-type mice after the non-noxious stimulation was larger than that of GluR2 and GluR3 delta7 KI mice. The present findings suggest that GluR2 and GluR3 subunits of AMPA receptor play roles in the trigeminal nerve injury-mediated enhancement of Vc and C1-C2 neuronal excitability, and hyperalgesia.  相似文献   
999.
1000.
Chylous joint effusion is a rare condition in which synovial fluids containing large amounts of lipids take on a milky appearance as a result. We report on a 19-year-old male patient with posttraumatic chylous knee effusion. Several days after striking his knee against the ground because of a traffic accident, his left knee showed obvious swelling. Aspiration of his knee was performed, yielding 70 ml of purulent-appearing fluid. To distinguish this condition from purulent or tuberculosis arthritis, arthroscopic biopsy and debridement were performed. Arthroscopic examination visualized distinctive yellow-white soft lesions covering much of the joint capsule, resembling a cobweb. Tissue cultures for bacteria were negative. Pathologically, we identified clusters of xanthoma cells with fibrin exudation due to disruption of the synovium and intra-articular fat pad necrosis. Centrifuging the aspiration fluid yielded a thick creamy lipid layer as the supernatant. A fresh drop preparation showed that the specimen contained innumerable fat globules, which stained red with oil red O stain. The patient was able to walk without difficulty or further swelling of his knee at the end of the second postoperative week. Posttraumatic chylous effusion is self-limited. Purulent arthritis or tuberculosis arthritis, however, should still be the presumptive diagnosis in such cases. Arthroscopic irrigation and debridement should be considered for these traumatic cases to confirm diagnosis and to speed up recovery.  相似文献   
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