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1.
An animal model, using distraction force on adult rabbits, was developed to study the effects of nonweight-bearing on articular cartilage in a moving joint. Histologic evaluation was used to compare the morphology of chondrocytes, safranin O intensity, cartilage thickness, and structural changes between the test and contralateral joints. At 3 and 6 weeks, the chondrocytes in superficial and intermediate zones were round, with an increase in cellular volume density and mean cell volume and with less metachromasia; the safranin O intensity and cartilage thickness were the same as in the controls. In cartilage of the 9-week group, mean cell volume decreased with cell cloning in the superficial zone, while numerical density increased and mean matrix volume per cell decreased in the superficial and intermediate zones. The cartilage, with a 34% reduction in thickness and a 53–72% decrease in safranin O intensity from the superficial to the deep zone, had superficial fibrotic proliferation, suface erosion or depression, ard tidemark irregularity. Continuous distraction in a moving joint caused morphological changes in chondrocytes prior to degeneration of cartilage. These results support the hypothesis that the forces perceived by cells may dictate their shape and then stimulate alterations in cellular biochemistry and matrix metabolism.  相似文献   
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Several studies have suggested that the regulator of G-protein signaling 4 (RGS4) may be a positional and functional candidate gene for schizophrenia. Three single nucleotide polymorphisms (SNP) located at the promoter region (SNP4 and SNP7) and the intron 1 (SNP18) of RGS4 have been verified in different ethnic groups. Positive results have been reported in these SNPs with different numbers of SNP combinatory haplotypes. In this study, these three SNP markers were genotyped in 218 schizophrenia pedigrees of Taiwan (864 individuals) for association analysis. Among these three SNPs, neither SNP4, SNP7, SNP18 has shown significant association with schizophrenia in single locus association analysis, nor any compositions of the three SNP haplotypes has shown significantly associations with the DSM-IV diagnosed schizophrenia. Our results fail to support the RGS4 as a candidate gene for schizophrenia when evaluated from these three SNP markers.  相似文献   
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The group I metabotropic glutamate receptor agonist DHPG has been shown to produce two major effects on CA3 pyramidal cells at rest: a reduction in the background conductance and an activation of a voltage-gated inward current ( I mGluR(V)). Both effects contribute to depolarising CA3 pyramidal cells and the latter has been implicated in eliciting prolonged epileptiform population bursts. We observed that DHPG-induced depolarisation was smaller in CA1 pyramidal cells than in CA3 cells. Voltage clamp studies revealed that while DHPG elicited I mGluR(V) in CA3 pyramidal cells, such a response was absent in CA1 pyramidal cells. Both mGluR1 and mGluR5 have been localised in CA3 pyramidal cells, whereas only mGluR5 has been detected in CA1 pyramidal cells. Using mGluR1 knockout mice, we evaluated whether the absence of an I mGluR(V) response can be correlated with the absence of mGluR1. In these experiments, DHPG failed to elicit I mGluR(V) in CA3 pyramidal cells. This suggests that the smaller depolarising effects of DHPG on wild-type CA1 pyramidal cells is caused, at least in part, by the absence of I mGluR(V) in these cells and that the difference in the responses of CA1 and CA3 cells may be attributable to the lack of mGluR1 in CA1 pyramidal cells.  相似文献   
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Leukemia is one of the major diseases causing cancer‐related deaths in the young population, and its cure rate is unsatisfying with side effects on patients. Fluorouracil (5‐FU) is currently used as an anticancer drug for leukemia patients. Casticin, a natural polymethoxyflavone, exerts anticancer activity against many human cancer cell lines in vitro, but no other reports show 5‐FU combined with casticin increased the mouse leukemia cell apoptosis in vitro. Herein, the antileukemia activity of 5‐FU combined with casticin in WEHI‐3 mouse leukemia cells was investigated in vitro. Treatment of two‐drug combination had a higher decrease in cell viability and a higher increase in apoptotic cell death, the level of DNA condensation, and the length of comet tail than that of 5‐FU or casticin treatment alone in WEHI‐3 cells. In addition, the two‐drug combination has a greater production rate of reactive oxygen species but a lower level of Ca2+ release and mitochondrial membrane potential (ΔΨm) than that of 5‐FU alone. Combined drugs also induced higher caspase‐3 and caspase‐8 activities than that of casticin alone and higher caspase‐9 activity than that of 5‐FU or casticin alone at 48 hours treatment. Furthermore, 5‐FU combined with casticin has a higher expression of Cu/Zn superoxide dismutase (SOD [Cu/Zn]) and lower catalase than that of 5‐FU or casticin treatment alone. The combined treatment has higher levels of Bax, Endo G, and cytochrome C of proapoptotic proteins than that of casticin alone and induced lower levels of B‐cell lymphoma 2 (BCL‐2) and BCL‐X of antiapoptotic proteins than that of 5‐FU or casticin only. Furthermore, the combined treatment had a higher expression of cleaved poly (ADP‐ribose) polymerase (PARP) than that of casticin only. Based on these findings, we may suggest that 5‐FU combined with casticin treatment increased apoptotic cell death in WEHI‐3 mouse leukemia cells that may undergo mitochondria and caspases signaling pathways in vitro.  相似文献   
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The aim of this study was to provide a systematic review and meta‐analysis of reports comparing laparoendoscopic single‐site (LESS) living‐donor nephrectomy (LDN) vs standard laparoscopic LDN (LLDN). A systematic review of the literature was performed in September 2013 using PubMed, Scopus, Ovid and The Cochrane library databases. Article selection proceeded according to the search strategy based on Preferred Reporting Items for Systematic Reviews and Meta‐analyses criteria. Weighted mean differences (WMDs) were used to measure continuous variables and odds ratios (ORs) to measure categorical ones. Nine publications meeting eligibility criteria were identified, including 461 LESS LDN and 1006 LLDN cases. There were more left‐side cases in the LESS LDN group (96.5% vs 88.6%, P < 0.001). Meta‐analysis of extractable data showed that LLDN had a shorter operative time (WMD 15.06 min, 95% confidence interval [CI] 4.9–25.1; P = 0.003), without a significant difference in warm ischaemia time (WMD 0.41 min, 95% CI –0.02 to 0.84; P = 0.06). Estimated blood loss was lower for LESS LDN (WMD ?22.09 mL, 95% CI –29.5 to –14.6; P < 0.001); however, this difference was not clinically significant. There was a greater likelihood of conversion for LESS LDN (OR 13.21, 95% CI 4.65–37.53; P < 0.001). Hospital stay was similar (WMD –0.11 days, 95% CI –0.33 to 0.12; P = 0.35), as well as the visual analogue pain score at discharge (WMD –0.31, 95% CI –0.96 to 0.35; P = 0.36), but the analgesic requirement was lower for LESS LDN (WMD –2.58 mg, 95% CI –5.01 to –0.15; P = 0.04). Moreover, there was no difference in the postoperative complication rate (OR 1.00, 95% CI 0.65–1.54; P = 0.99). Renal function of the recipient, as based on creatinine levels at 1 month, showed similar outcomes between groups (WMD 0.10 mg/dL, –0.09 to 0.29; P = 0.29). In conclusion, LESS LDN represents an emerging option for living kidney donation. This procedure offers comparable surgical and early functional outcomes to the conventional LLDN, with a lower analgesic requirement. However, it is more technically challenging than LLDN, as shown by a greater likelihood of conversion. The role of LESS LDN remains to be defined.  相似文献   
7.
Clinical trials have indicated that sodium-glucose co-transporter-2 (SGLT2) inhibitors have a favourable effect on serum alanine aminotransferase (ALT) levels in people with type 2 diabetes (T2D), but supporting evidence from real-world studies is lacking. We identified patients with T2D who initiated SGLT2 inhibitors during the period 2016 to 2017 from Chang Gung Research Database, which covers 1.3 million individuals from seven hospitals (6% of the Taiwan population). We classified patients by baseline ALT level and evaluated changes in ALT values from baseline to 1 year after initiation of SGLT2 inhibitors. We identified 11 690 new users of SGLT2 inhibitors with a mean (SD) age of 59.3 (11.8) years. The mean (SD) glycated haemoglobin and ALT levels were 8.9 (1.7)% and 34.7 (28.9) U/L at baseline, respectively. The mean change in ALT levels was −5.0 U/L (95% confidence interval [CI] –6.4, −3.5) 1 year after initiation of SGLT2 inhibitors. In patients with ALT levels ≤1× the upper limit of normal (ULN), the change in ALT levels was 1.6 U/L (95% CI –0.1, 3.4), while in those with ALT levels >1× ULN, the change in ALT levels was −26.5 U/L (95% CI –28.6, −24.3). The higher the baseline ALT level, the greater the decline after SGLT2 inhibitor treatment. Our findings suggest the initiation of SGLT2 inhibitors for T2D management could improve serum ALT levels in clinical practice, particularly in patients with especially high ALT levels.  相似文献   
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