Expression of alpha-smooth muscle actin by and contraction of cells derived from synovium

Cells derived from synovium have drawn interest as donor cells for articular cartilage tissue engineering because they have been implicated in certain cartilage repair processes in vivo and the chondrogenic potential of the cells has been demonstrated in vitro. Studies have demonstrated that several other types of musculoskeletal connective tissue cells--including chondrocytes, fibrochondrocytes, ligament fibroblasts and osteoblasts, and mesenchymal stem cells can express the gene for the contractile actin isoform, alpha-smooth muscle actin (SMA), and can contract analogs of extracellular matrix in vitro. Although the physiological roles of SMA-enabled contraction of these cells have yet to be established, cell-mediated contraction of scaffolds employed for tissue engineering can alter the pore diameter of the matrix and distort its overall shape, and thus needs to be addressed. Toward this goal, the objective of this study was to investigate the expression of SMA by synovial cells and to evaluate their contraction of collagen-glycosaminoglycan (GAG) scaffolds. Synovial membranes obtained from the knees (stifle joints) of six adult dogs were evaluated for the presence of SMA by immunohistochemistry. Cells isolated from the synovial tissue were expanded through seven passages in monolayer culture, with samples from each passage allocated for Western blot analysis of SMA. Cells from passage 4 were seeded into porous type I collagen-GAG matrices and cultured for 4 weeks. Synovial cell-mediated contraction of the scaffolds was determined by measuring the diameters of the cell-seeded scaffolds and nonseeded controls every other day. Synovium-derived cells cultured as micropellets or in collagen-GAG matrices were incubated in chondrogenic medium with and without fetal bovine serum and evaluated for chondrogenesis by type II collagen immunohistochemistry. Immunohistochemistry revealed the presence of SMA in some cells (less than 10% of the cells) in the intimal layer of synovium from four of the five animals analyzed. Western blot analysis demonstrated a regular increase in the amount of SMA in the synovium-derived cells with passage number. Synovial cell-mediated contraction of the collagen-GAG scaffolds reached a value of 43% of the original diameter after 4 weeks, comparable to that found with other musculoskeletal cell types. Incubation of micropellet cultures of synovium-derived cells with chondrogenic medium revealed trace amounts of type II collagen production by immunohistochemistry. The findings of this study indicate that control of SMA-enabled contraction may be important when employing synovial cells for cartilage repair procedures, and warrant further investigation into the physiological role of SMA expression in synovial cells.     

Adelta and C primary afferents convey dorsal root reflexes after intradermal injection of capsaicin in rats

Antidromic activity was recorded in anesthetized rats from single afferent fibers in the proximal ends of cut dorsal root filaments at the L(4-6) level and tested for responses to acute cutaneous inflammation produced by intradermal injection of capsaicin. This antidromic activity included low-frequency spontaneous firing and dorsal root reflex (DRR) discharges evoked by applying von Frey hairs to the skin of the foot. DRRs could be recorded from both small myelinated (Adelta) and unmyelinated (C) afferent fibers, as well as from large myelinated (Abeta) fibers. After capsaicin was injected intradermally into the plantar skin of the foot, a significant enhancement of DRR activity was seen in Adelta and C fibers but not in Abeta fibers, and this increase lasted for approximately 1 h. This study supports the hypothesis that centrally mediated antidromic activity in Adelta and C primary afferent fibers contributes to the development of neurogenic inflammation, presumably by release of inflammatory substances in the periphery.     

Effects of a Short-Term “Fat Adaptation with Carbohydrate Restoration” Diet on Metabolic Responses and Exercise Performance in Well-Trained Runners

Periodized carbohydrate availability can enhance exercise capacity, but the effects of short-term fat adaptation carbohydrate restoration (FACR) diets on metabolic responses and exercise performance in endurance athletes have not been conclusively determined. This study aimed to investigate the effect of a FACR diet on measures of resting metabolism, exercise metabolism, and exercise performance. Well-trained male runners (n = 8) completed a FACR dietary intervention (five days’ carbohydrate < 20% and fat > 60% energy, plus one-day carbohydrate ≥ 70% energy), and a control high-carbohydrate (HCHO) diet for six days (carbohydrate > 60% energy; fat < 20% energy) in a randomized crossover design. Pre- and post-intervention metabolic measures included resting metabolic rate (RMR), respiratory quotient (RQ), maximum fat oxidation rate during exercise (MFO), and maximum fat oxidation intensity (FATmax). Measures of exercise performance included maximal oxygen uptake (VO₂max), running economy (RE), and 5 km running time trial (5 km-TT). In FACR compared with HCHO, there were significant improvements in FATmax (p = 0.006) and RE (p = 0.048). There were no significant differences (p > 0.05) between FACR and HCHO in RMR, RQ, VO₂max, or 5 km-TT. Findings suggest that a short-term (six days) FACR diet may facilitate increased fat oxidation and submaximal exercise economy but does not improve 5 km-TT performance.     

LT受体拮抗剂对大鼠肺纤维化LTB_4及血F_n的影响

45只大鼠随机分为 3组 ,对照组、模型组、治疗组各 15只。治疗组气管内单次灌注博莱霉素 (5 mg)后每日以安可来 (ACL,10 mg/ kg)灌胃 ;模型组气管内灌注同治疗组 ,灌胃以生理盐水代替。 3组动物在气管内灌注后分别于第 7、14、2 8d随机处死 5只 ,取左肺下叶 1g匀浆测 L TB4,心腔血测纤维联结蛋白 (Fn)。模型组和治疗组在气管内灌注后白三烯 B4(L TB4)迅速上升 ,第 7d达高峰 ,第 2 8d模型组 L TB4仍较高 ,治疗组 L TB4明显下降 ;Fn浓度模型组在第 7d明显升高 ,治疗组及对照组较低。结论 :在鼠实验性肺间质化过程中 L TB4明显增高 ,白三烯对肺间质纤维化的发生发展起一定作用     

LT受体拮抗剂对大鼠肺纤维化LTB4及血Fn的影响

45只大鼠随机分为3组,对照组、模型组、治疗组各15只。治疗组气定内单次灌注博莱霉素（5mg)后每日以安可来（ACL,10mg/kg)灌胃;模型组气管内灌注同治疗组,灌胃以生理盐水代替。3组动物在气管内灌注后分别于第7、14、28d随机处死5只,取左肺下叶1g匀浆测LTB4,心腔血测纤维联结蛋白（Fn)。模型组和治疗组在气管内灌注后白三烯B4（LTB4）迅速上升,第7d达高峰,第28d模型组LTB4仍较高,治疗组LTB4明显下降;Fn浓度模型组在第7d明显升高,治疗组及对照组较低。结论：在鼠实验性肺间质化过程中LTB4明显增高,白三烯对肺间质纤维化的发生发展起一定作用。     

血清血管内皮生长因子测定在鼻咽癌检测中的意义

目的：探讨血清血管内皮生长因子能否作为鼻咽癌的肿瘤标志物,并作为鼻咽癌诊断与分期检测的指标。方法：对88例鼻咽癌患者和60例鼻咽颈部良性病变及73例正常人进行血清血管内皮生长因子的定量测定。结果：鼻咽癌患者与鼻咽颈部良性病变、正常人比较和鼻咽癌临床各期比较血清血管内皮生长因子含量有显著性的差异。结论：血清血管内皮生长因子含量测定可作为鼻咽癌的发现诊断和临床分期简便可靠的检测指标。     

复发性口腔溃疡与血清TNF-α,TGF-β浓度关系的临床研究

目的 :研究复发性口腔溃疡与血清TNF α,TGF β浓度关系。方法 :选择复发性口腔溃疡患者 3 2例 ,采用ELISA检测其血清TNF α ,TGF β水平 ,并与正常成年人作对照。结果 :复发性口腔溃疡患者TNF α水平较正常组明显升高 (P <0 .0 1) ,TGF β水平与正常组相比 ,无显著统计学差异 (P >0 .0 5 )。结论 :复发性口腔溃疡的致病过程与细胞因子TNF α有关 ,与TGF β关系不密切     

端粒酶及nm23的表达与胃腺癌预后的关系探讨

目的 :探讨端粒酶和nm2 3癌基因蛋白表达与胃癌根治术后复发及预后的关系。方法 :采用端粒酶原位分子杂交技术及免疫组化S P法分别对 4 5例原发性胃腺癌组织中端粒酶的活性及nm2 3进行检测 ,并结合内镜及随访资料进行分析。结果 :胃腺癌端粒酶阳性表达率及nm2 3低表达率在有淋巴结转移组显著高于无淋巴结转移组 ;在术后 5年内复发者中显著高于无复发者。虽然随着胃腺癌分化程度的降低及浸润深度的增加 ,端粒酶活性及nm2 3低表达呈增强趋势 ,但其差异无统计学意义。结论 :胃腺癌组织中端粒酶的活性表达及nm2 3的低表达与淋巴结转移及术后复发显著相关 ,两者的表达变化对判断胃癌术后复发及预后判断有重要临床意义     

Clinical significance and assessment of cytokines in various stages of ulcerative colitis

Summary In order to study the clinical significance and change of interleukin (IL)-1β and IL-10 concentration in intestinal mucosal tissues in various stage of ulcerative colitis (UC), IL-1β and IL10 levels were measured by enzyme linked immunosorbent assays (ELISA). Our results showed that IL-β level caused by spontaneous secretion in the intestinal mucous tissues in active stage of ulcerative colitis was significantly higher than that in normal controls and in remission stage of ulcerative colitis (P <0. 01,P<0. 001). IL-10 level in various stage of UC was relatively lower in controls, but there was no significantly difference between the two groups. Our study suggested that higher IL-1β level in active might play an important role in pathogenesis of UC, and IL-10, as an anti-inflammatory cytokine, was low in active UC, suggesting that it may be a important factor contributing to the development of higher IL-1β level. This project was supported by the grant of the Scientific Research Fund of the Ministry of Health (No. 98-2-387).