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81.
Steve W. N. Ueng Li‐Jen Yuan Song‐Shu Lin Chi‐Chien Niu Yi‐Sheng Chan I‐Chun Wang Chuen‐Yung Yang Wen‐Jer Chen 《Journal of orthopaedic research》2013,31(3):376-384
Heat shock proteins (HSPs), inflammatory cytokines, nitric oxide (NO), and localized hypoxia‐induced apoptosis are thought to be correlated to the degree of cartilage injury. We investigated the effect of hyperbaric oxygen (HBO) on (1) interleukin‐1β (IL‐1β)‐induced NO production and apoptosis of rabbit chondrocytes and (2) healing of articular cartilage defects. For the in vitro study, RT‐PCR and Western blotting were performed to detect mRNA and protein expressions of HSP70, inducible NO synthase (iNOS), and caspase 3 in IL‐1β‐treated chondrocytes. To clarify that the HSP70 was necessary for anti‐iNOS and anti‐apoptotic activity by HBO, we treated the cells with an HSP70 inhibitor, KNK437. For the in vivo study, cartilage defects were created in rabbits. The HBO group was exposed to 100% oxygen at 2.5 ATA for 1.5 h a day for 10 weeks. The control group was exposed to normal air. After sacrifice, specimen sections were sent for examination using a scoring system. Immunohistochemical analyses were performed to detect the expressions of iNOS, HSP70, and caspase 3. Our results suggested that HBO upregulated the mRNA and protein expressions of HSP70 and suppressed those of iNOS and caspase 3 in chondrocytes. KNK437 inhibited the HBO‐induced downregulation of iNOS and casapase 3 activities. The histological scores showed that HBO markedly enhanced cartilage repair. Immunohistostaining showed that HBO enhanced HSP70 expression and suppressed iNOS and caspase 3 expressions in chondrocytes. Accordingly, HBO treatment prevents NO‐induced apoptosis in articular cartilage injury via enhancement of the expression of heat shock protein 70. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 376–384, 2013 相似文献
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Xiang‐Rong Sun Lei Chen Wen‐Fang Chen Yan Xue Wing‐Ho Yung 《Synapse (New York, N.Y.)》2013,67(12):831-838
The globus pallidus plays a critical role in movement regulation. Glutamate being an important excitatory neurotransmitter modulates the activity of pallidal neurons through both ionotropic and metabotropic glutamate receptors (mGluRs). Morphological studies have shown that group III mGluRs are generally located presynaptically in the globus pallidus. Up to now, little is known about the in vivo electrophysiological effects of group III mGluRs on the pallidal neurons. This study investigated the electrophysiological and behavioral effects of group III mGluRs on pallidal neurons in both normal and 6‐hydroxydopamine (6‐OHDA) lesioned parkinsonian rats. Micropressure ejection of group III mGluR agonist, l ‐2‐amino‐4‐phosphonobutyrate (l ‐AP4), increased or decreased the firing rate of pallidal neurons in both normal and parkinsonian rats. The l ‐AP4‐induced excitatory effects on the lesioned side of parkinsonian rats (117.4 ± 17.2%) were stronger than that in normal rats (64.3 ± 10.1%). While the proportion of neurons that were unresponsive to l ‐AP4 on the lesioned side of parkinsonian rats (50%) was more than that of normal rats (13%). Unilateral microinjection of l ‐AP4 into the globus pallidus induced a contralateral dystonic posturing in the presence of systemic haloperidol administration. The selective group III mGluRs antagonist, (RS)‐α‐cyclopropyl‐4‐phosphonophenylglycine, had no effect on pallidal neurons when used alone and could block both l ‐AP4‐induced electrophysiological and behavioral effects. Combining electrophysiological and behavioral findings, we concluded that activation of group III mGluRs modulate the activity of pallidal neurons under both normal and parkinsonian state. Synapse 67:831–838, 2013 . © 2013 Wiley Periodicals, Inc. 相似文献
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Eva Velthorst Barnaby Nelson Suzanne Wiltink Lieuwe de Haan Stephen J. Wood Ashleigh Lin Alison R. Yung 《Schizophrenia Research》2013,143(1):132-137
BackgroundBaseline functioning has been found to be a strong predictor of transition to psychosis in ultra high risk populations. However, the time course of functioning may enhance prediction. We investigated whether there were different patterns of functioning over time and whether particular temporal patterns were related to baseline characteristics and psychosis outcome.MethodFunctional data was assessed at baseline and after 3 to 6 year follow-up in an ultra high risk sample (n = 158; 92 female, mean age = 19.28 (SD = 3.33), range = 14–29). Using the median score of the GAF and the QLS scale, a ‘High’ and ‘Low’ group (comprising of subjects functioning above or below median at both baseline and follow-up) and a ‘Deterioration’ group and ‘Improving’ group were created.ResultsChi-square analyses showed that the Low and Deteriorating functioning groups were the most likely to develop first-episode psychosis (FEP). Importantly, UHR individuals with deteriorating functioning were at higher risk of transition than those whose functioning was low at baseline but improved over time (GAF: X2 = 5.10, df = 1, p = .02; QLS: X2 = 9.13, df = 1, p = .003). Binary logistic regression analyses showed that a decline in functioning was more strongly associated with FEP (GAF: p = < .0001; QLS: p < .0001) than the level of baseline functioning (GAF: p = .005; QLS: p = .09). The deteriorating group could not be distinguished from the High group in terms of baseline symptomatology.DiscussionWith the addition of the ‘low functioning’ criterion to the UHR criteria, we may miss out on some true positive cases. Limiting our attention to baseline poor functioning may therefore distort the picture in terms of risk for psychosis. 相似文献
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Min Gi Shin Kun Yung Kim Young-Min Han Kyoung Min Kim Yu Seob Shin 《Journal of vascular and interventional radiology : JVIR》2019,30(5):655-660
PurposeTo investigate the safety and effectiveness of preoperative prostatic artery embolization (PAE) in relation to decrease in hemoglobin level, requirement for blood transfusion, length of hospitalization, and procedure-related complications.Materials and MethodsTen consecutive patients who underwent surgery after preoperative PAE were identified from May 2017 to October 2018 (embolization group: holmium-laser enucleation of the prostate [HoLEP] in 6 patients and robotic simple prostatectomy in 4 patients, mean age 72.9 ± 8.7 years, mean prostatic volume 106.5 ± 22.0 mL). For comparison, consecutive patients with a large prostatic volume (≥70 mL) who underwent surgery without preoperative PAE during the same period were enrolled (nonembolization group: HoLEP in 9 patients and robotic simple prostatectomy in 1 patients, mean age 71.2 ± 5.7 years, mean prostatic volume 87.8 ± 26.7 mL).ResultsPAE was technically successful in 90% of patients (9/10). The median interval between PAE and surgery was 2 days. The mean hemoglobin reduction was lower (1.40 ± 0.92 g/dL vs 3.07 ± 1.50 g/dL; P = .008) and the median length of hospitalization was shorter (8.5 days vs 11 days; P = .039) in the embolization group than the nonembolization group. The operating time (mean for HoLEP 146 ± 38 min vs 179 ± 59 min [P = .248], mean for robotic simple prostatectomy 223 ± 32 min vs 354 min) and number of blood transfusion (1 patient vs 2 patients; P = .392) were not significantly different between the 2 groups. None of the patients developed any complications except bleeding requiring transfusion.ConclusionsPreoperative PAE is safe and may reduce blood loss during prostate surgery. 相似文献
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Effect of radial shock wave therapy for carpal tunnel syndrome: A prospective randomized,double‐blind,placebo‐controlled trial 下载免费PDF全文
Yung‐Tsan Wu Ming‐Jen Ke Yu‐Ching Chou Chih‐Ya Chang Ching‐Yueh Lin Tsung‐Ying Li Feng‐Mei Shih Liang‐Cheng Chen 《Journal of orthopaedic research》2016,34(6):977-984
Three recent studies demonstrated the positive effect of extracorporeal shock wave therapy (ESWT) for treating carpal tunnel syndrome (CTS). However, none have entirely proved the effects of ESWT on CTS because all studies had a small sample size and lacked a placebo‐controlled design. Moreover, radial ESWT (rESWT) has not been used to treat CTS. We conducted a prospective randomized, controlled, double‐blinded study to assess the effect of rESWT for treating CTS. Thirty‐four enrolled patients (40 wrists) were randomized into intervention and control groups (20 wrists in each). Participants in the intervention group underwent three sessions of rESWT with nightly splinting, whereas those in the control group underwent sham rESWT with nightly splinting. The primary outcome was visual analog scale (VAS), whereas the secondary outcomes included the Boston Carpal Tunnel Syndrome Questionnaire (BCTQ), cross‐sectional area (CSA) of the median nerve, sensory nerve conduction velocity of the median nerve, and finger pinch strength. Evaluations were performed before treatment and at 1, 4, 8, and 12 weeks after the third rESWT session. A significantly greater improvement in the VAS, BCTQ scores, and CSA of the median nerve was noted in the intervention group throughout the study as compared to the control group (except for BCTQ severity at week 12 and CSA at weeks 1 and 4) (p < 0.05). This is the first study to assess rESWT in a randomized placebo‐controlled trial and demonstrate that rESWT is a safe and effective method for relieving pain and disability in patients with CTS. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:977–984, 2016. 相似文献
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Although previously described as an inert space filler, there is now compelling evidence to underscore the importance of hyaluronan in physiologic and pathologic processes. Despite its simple structure, hyaluronan plays essential roles in embryonic development, phenotypic changes, proliferation, wound healing, inflammation and angiogenesis. Hyaluronan is a major component of the glycocalyx that forms a protective barrier around mesothelial cells, and bestows upon the peritoneal membrane a slippery non-adhesive surface preventing abrasion, infection and tumor dissemination. Hyaluronan is associated with mesothelial-to-mesenchymal transdifferentiation, recruitment of leukocytes to sites of inflammation, and mediates the reparative process after tissue injury by initiating increased synthesis of growth factors. Serum and dialysate levels of hyaluronan are increased in patients maintained on peritoneal dialysis (PD), of which the levels are further increased during episodes of peritonitis. The level of hyaluronan in PD effluents is often used as a surrogate marker for peritoneal inflammation and can predict patient survival. This review will describe the multifaceted roles of hyaluronan in the peritoneum and how these roles are modulated during PD. 相似文献
90.
Birmingham DJ Irshaid F Gavit KF Nagaraja HN Yu CY Rovin BH Hebert LA 《Molecular immunology》2007,44(14):3510-3516
The type one complement receptor (CR1) contains a variable number of binding domains for C3b and C4b, formed through a nearly identical set of repeating units known as short consensus repeats (SCRs). Each SCR contains four cysteines that, by forming two disulfide bonds, impart a conformation critical for function. In this study, we identified a CR1 single nucleotide polymorphism (1597C>T) that results in an additional cysteine (483R>C) in SCR 8 of the N-terminal C3b/C4b binding domain, and occurring sporadically in corresponding SCRs of other repeated C3b/C4b binding domains. The normal carrier frequency for 483-C was 6.3% in 175 African Americans, and 2.4% in 153 Caucasians. In expression constructs containing one C3b/C4b binding domain, the 483-C residue reduced binding to C3b, C3bi, and C4b by over 80% (each p<0.0001), versus the wildtype construct. Full-length CR1 from 483-C carriers also exhibited reduced binding to C3b and C4b, although the effect was influenced by the total number of binding domains present. Race-matched comparisons between SLE patients (86 African Americans, 228 Caucasians) and the normal cohort showed that 483-C carrier status alone is not a risk factor for SLE or lupus nephritis. The physiological role of this polymorphism remains to be determined. 相似文献