Ⅸ型胶原与骨性关节炎

骨性关节炎(OA)是在力学和生物学因素的共同作用下,软骨细胞、细胞外基质(ECM)及软骨下骨三者间分解和合成代谢失衡的结果。其病因及发病机制尚未明了,目前有多种学说解释OA的发生机制。一种观点认为,在某些炎症介质和细胞因子的作用下,基质金属蛋白酶的分泌异常增多,分解ECM,导致OA发生:另一种观点认为反复过量的负荷会损害软骨细胞和ECM,导致OA发生;还有一种观点认为,软骨细胞过度凋亡可能在OA的发病中产生了重要影响。     

碱性成纤维细胞生长因子缓释微球治疗兔膝骨关节炎

骨关节炎(OA)的主要病理改变为关节软骨的损伤退变.碱性成纤维细胞生长因子(bFGF)是最有效的软骨细胞分裂素,bFGF缓释微球能维持其关节腔内的有效浓度.目前研究表明基质金属蛋白酶(MMP)-13、基质金属蛋白酶抑制剂(TIMP)-1为软骨细胞外基质合成和降解的主要调节因子.本研究旨在观察bFGF缓释微球治疗兔膝OA对MMP-13和TIMP-1 mRNA表达的影响,探讨bFGF治疗OA的作用机制.     

基质金属蛋白酶9及TGF-β_1 mRNA和蛋白在骨关节炎中的表达

目的 TGF-β1对骨关节炎(osteoarthritis,OA)关节软骨起保护作用,探讨OA中基质金属蛋白酶9(matrix metalloproteinase 9,MMP-9)、TGF-β1 mRNA和蛋白表达的相关性,为临床治疗OA寻找有效的干预靶点提供理论依据。方法取自愿捐赠的关节软骨及滑膜标本,其中OA患者60例(实验组),外伤截肢、交叉韧带断裂、盘状软骨损伤与半月板损伤患者20例(正常对照组)。行HE染色观察关节软骨与滑膜的病理组织学改变,免疫组织化学染色观测MMP-9及TGF-β1蛋白表达,原位杂交技术检测MMP-9及TGF-β1 mRNA表达;并进行相关性分析。结果 HE染色显示实验组关节软骨细胞固缩、坏死、排列紊乱,细胞外基质断裂,关节滑膜细胞肥大增生、淋巴细胞和单核细胞浸润,多数小血管增生;正常对照组软骨细胞排列整齐、基质染色均匀,滑膜组织无慢性炎症表现、无明显增生。两组均可见MMP-9、TGF-β1 mRNA和蛋白阳性表达,阳性细胞包括软骨细胞、滑膜衬里层细胞及滑膜下层的血管内皮细胞、成纤维细胞、炎性浸润细胞等。实验组MMP-9及TGF-β1 mRNA和蛋白表达均高于正常对照组(P<0....     

髋关节骨性关节炎组织学计量与炎性因子表达

目的 探讨骨性关节炎各组织成分中细胞冈子、金属基质蛋白酶等炎性物质表达水平与疾病的关系.方法 获取行OA组关节置换及创伤性股骨颈骨折组患者手术时的软骨、滑膜组织和软骨下骨,苏木素-伊红(HE)染色行软骨下骨组织形态计量分析,应用放射免疫测定肿瘤坏死因子(TNF)-α与门细胞介素(IL)-1β,以酶联免疫吸附试验(ELISA)测金属基质蛋白酶(MMP)-9蛋白表达水平,并将两组结果进行t检验,软骨下骨组织计量值与细胞因子水平进行相关分析.结果 OA组较非OA对照组软骨下骨骨形成增加,骨质硬化骨小梁数目增加并错乱;滑膜组织中MMP-9表达是调;软骨组织中MMP-9及IL-1 β较对照组提高;而在软骨下骨,MMP-9、TNF-α及IL-β均有增高,并且与软骨下骨组织学改变相关联.结论 证实了OA促炎症条件的病理学基础,并且炎性改变与软骨硬化及关节软骨退变相关.     

基质金属蛋白酶9及TGF-β1 mRNA和蛋白在骨关节炎中的表达

目的 TGF-β1对骨关节炎(osteoarthritis,OA)关节软骨起保护作用,探讨OA中基质金属蛋白酶9(matrix metalloproteinase 9,MMP-9)、TGF-β1 mRNA和蛋白表达的相关性,为临床治疗OA寻找有效的干预靶点提供理论依据。方法取自愿捐赠的关节软骨及滑膜标本,其中OA患者60例(实验组),外伤截肢、交叉韧带断裂、盘状软骨损伤与半月板损伤患者20例(正常对照组)。行HE染色观察关节软骨与滑膜的病理组织学改变,免疫组织化学染色观测MMP-9及TGF-β1蛋白表达,原位杂交技术检测MMP-9及TGF-β1 mRNA表达;并进行相关性分析。结果 HE染色显示实验组关节软骨细胞固缩、坏死、排列紊乱,细胞外基质断裂,关节滑膜细胞肥大增生、淋巴细胞和单核细胞浸润,多数小血管增生;正常对照组软骨细胞排列整齐、基质染色均匀,滑膜组织无慢性炎症表现、无明显增生。两组均可见MMP-9、TGF-β1 mRNA和蛋白阳性表达,阳性细胞包括软骨细胞、滑膜衬里层细胞及滑膜下层的血管内皮细胞、成纤维细胞、炎性浸润细胞等。实验组MMP-9及TGF-β1 mRNA和蛋白表达均高于正常对照组(P<0.01)。实验组MMP-9 mRNA与蛋白表达成正相关(r=0.924,P=0.000),TGF-β1 mRNA及蛋白表达亦成正相关(r=0.941,P=0.000);实验组MMP-9及TGF-β1蛋白表达成负相关(r=—0.762,P=0.000),MMP-9 mRNA及TGF-β1 mRNA表达成负相关(r=?0.681,P=0.000)。结论 OA中TGF-β1的高表达下调了关节软骨与滑膜中MMP-9的表达,对OA关节软骨起保护作用,从而延缓OA进展。     

槲皮素对人类风湿性关节炎成纤维样滑膜细胞炎症因子和基质金属蛋白酶的表达的影响

目的探讨槲皮素对类风湿性关节炎成纤维样滑膜细胞(MH7A)炎症因子和基质金属蛋白酶的表达的影响及可能机制。方法选用人类风湿性关节炎成纤维样滑膜细胞(MH7A)为研究对象,TNF-α诱导MH7A细胞,用不同浓度的槲皮素干预,RT-PCR法检测对IL-1β、IL-6、IL-8、MMP-1、MMP-3、MMP-13的变化的影响,Western blot法检测对NF-κB的影响。结果槲皮素浓度依赖性地降低TNF-α诱导的MH7A细胞IL-1β、IL-6、IL-8、MMP-1、MMP-3、MMP-13的表达,对TNF-α诱导的MH7A细胞NF-κB的磷酸化有明显的抑制作用。结论槲皮素可有效地减轻类风湿性关节炎成纤维样滑膜细胞炎症因子及基质金属蛋白酶的表达,其机制可能和抑制NF-κB的表达相关,槲皮素是治疗类风湿性关节炎的潜在有效药物。     

兔骨关节炎中基质金属蛋白酶-1、3与白细胞介素-1β表达及关节软骨细胞凋亡的研究

目的 观察骨关节炎(OA)中基质金属蛋白酶(MMP)-1、3与白细胞介素-1β(IL-1β)的表达及关节软骨细胞凋亡,探讨其在OA发病机制中的作用.方法 将20只中国大白兔随机分成正常组(A组)、实验组(B组),每组10只,A组未造模,B组采用Hulth法制成OA模型,4周后取胫骨平台关节软骨进行组织病理学检查,采用免疫组织化学和原位末端标记细胞凋亡检测法分别检测关节软骨和滑膜中的MMP-1、3、IL-1β及软骨细胞凋亡指数(AI)的水平.结果 组织病理学检查可见,B组关节软骨退变程度明显重于A组,符合OA关节软骨退变特征;通过检测MMP-1、3,IL-1β和AI,A组的结果分别是21.005±9.406、18.697±8.225、0.100±0.040和14.900±3.400,B组的结果分别是56.147±22.340、46.182±20.561、0.180±0.060和25.400 ±5.200;B组MMP-1、3和AI的水平均明显高于A组(P＜0.01),B组IL-1β水平高于A组(P＜0.05).结论 MMP-1、MMP-3、IL-1β的表达及关节软骨细胞凋亡在OA发病机制中作用重要,其异常升高与OA关节软骨退变和炎症反应密切相关.     

Smad与肾纤维化

转化生长因子-β(transforming growth factor-β,TGF-β)是介导肾小球硬化和肾间质纤维化关键的细胞因子，其作用包括趋化和活化炎性细胞，介导肾小管上皮细胞向间充质细胞转分化，以及刺激细胞外基质蛋白的合成及降低基质金属蛋白酶的活性和俄增加蛋白酶抑制剂的合成来促进细胞外基质的沉积。由于TGF-β在肾纤维化中的核心作用，TGF-β信号传导机制引起了人们极大的兴趣。     

柚皮苷抑制骨关节炎软骨细胞凋亡实验研究

目的研究柚皮苷在炎症环境下对人骨关节炎（OA）软骨细胞凋亡的影响和可能的作用机制。方法采用不同浓度（0、0．1、1、10、100 mg／L）柚皮苷对 OA 软骨细胞进行预处理2 h 后,加入或不加入炎症因子混合液（白细胞介素-1β5 ng／ml 和肿瘤坏死因子-α20 ng／ml）共作用24 h。首先检测柚皮苷对炎症环境下软骨细胞活性和凋亡的影响,然后检测软骨细胞在柚皮苷作用下的一氧化氮（NO）水平及半胱氨酸天冬氨酸特异性蛋白酶（caspase）-3、caspase-8活性变化情况。结果柚皮苷预处理后软骨细胞在炎症因子刺激下发生凋亡显著减轻,且其抑制细胞凋亡作用具有浓度依赖性。进一步分子生物学检测显示,柚皮苷对 NO 生成及激活的 caspase 信号转导通路具有明显抑制作用。结论柚皮苷能有效抑制人 OA 软骨细胞凋亡,其作用机制可能是柚皮苷阻断了 NO 产生并抑制了下游的 caspase 信号通路,有望应用于 OA 治疗新药的研发。     

NPWT促进糖尿病足溃疡创面愈合分子机制的初步研究

目的通过检测与创面愈合进程相关的组织基因表达,探讨采用负压创面治疗(nagetive pressure wound therapy,NPWT),促进糖尿病足溃疡(diabetic foot ulcer, DFU)愈合的作用机制。方法将纳入的50例DFU患者随机分成NPWT组(25例)和对照组(25例)。对照组接受局部湿敷治疗。两组患者治疗前后10 d均取创面肉芽行组织活检,利用RT-PCR检测转移生长因子-β1(transforminggrowth factor beta 1, TGF-β1)、血管内皮生长因子(vascular endothelial growth factor, VEGF)、肿瘤坏死因子-α(tumor necrosis factor-α, TNF-α)、白介素-1β(interleukin-1β, IL-1β)、基质金属蛋白酶-1(matrix metalloproteinase-1, MMP-1)、基质金属蛋白酶-9(matrixmetalloproteinase-9, MMP-9)和基质金属蛋白酶抑制剂-1(tissue inhibitor of metalloproteinase-1, TIMP-1)的mRNA表达,并进行对比分析。结果治疗后10 d,NPWT组患者创面肉芽组织中VEGF、TGF-β1和TIMP-1 mRNA的表达较治疗前显著增加,IL-1β、TNF-α、MMP-1和MMP-9 mRNA的表达显著下降(P<0.05);而对照组上述各项指标的mRNA表达,治疗前后均无显著变化(P>0.05)。结论 NPWT可能通过影响生长因子、炎症细胞因子和基质金属蛋白酶的表达来促进DFU愈合。     

Reduction of Plasma Fibrinogen, Immunoglobulin G, and Immunoglobulin M Concentrations by Immunoadsorption Therapy with Tryptophan and Phenylalanine Adsorbents

Abstract Immunoadsorption (1A) therapy with tryptophan (TR-350) or phenylalanine (PH-350) adsorbents has been used to reduce the concentration of serum antibodies in human lymphocyte antigen (HLA)-immunized patients. Other forms of plasma purification have been reported to reduce the level of fibrinogen, which affects the blood properties. In this study we investigated the effects of IA therapy using both adsorbents on plasma fibrinogen and immunoglobulins G and M in 13 patients (8 patients were treated with TR-350, and 5 patients were treated with PH-350). During each session 1 plasma volume (2.8 ± 0.4 L of plasma) was processed through the immunocolumn and then returned to the patient together with the blood cells. Compared with the pretreatment values, the plasma fibrinogen, IgG, and IgM concentrations were significantly reduced after IA therapy (p < 0.01 for TR-350; p < 0.04 for PH-350). There was a positive correlation between the degree of reduction of plasma proteins and the number of IA treatments given. A nonpara-metric test (Wilcoxon's signed-rank test or the Mann-Whitney test) was used for statistical analysis. We conclude from our study that IA therapy effectively lowers the plasma levels of fibrinogen, IgG, and IgM and thus can be considered a valuable alternative to other blood purification methods.     

Is the recovery profile of mivacurium independent of the rate of decay of its plasma concentration in patients with normal plasma cholinesterase activity?

Background: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. Methods: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg . kg^?1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg . kg^?1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg . kg^?1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. Results: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). Conclusion: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.     

Membranes in Artificial Organs

Abstract: Membrane processes play a pivotal and enabling role in modern replacement therapy for acute and chronic organ failure and in the management of immunologic diseases. In fact, virtually all contemporary extracorporeal blood purification methods employ membrane devices, and the next generation of artificial organs and tissue engineering therapies are almost certain to be similarly grounded in membrane technology. In this short essay, we comment on the similarities and differences among synthetic membranes and their natural counterparts and also provide a critical overview of the demographics and technology of hemodialysis, hemofiltration, apheresis, oxygenation, and emerging membrane technologies and applications.     

The multiply injured child

Blunt trauma is the principal cause of childhood death in many developed countries. This review outlines the differences between adults and children with respect to resuscitation and treatment of orthopaedic injuries in a child with polytrauma. Recent advances in techniques of fracture stabilization are reported.     

Dilemma of Membrane Biocompatibility and Reuse

Abstract: Numerous articles have been published on the multiple use of dialyzers and on the effect of different reprocessing chemicals and techniques on the dialyzer biocompatibility and performance. The results often appear contradictory, especially those comparing standard biocompatibility parameters. Despite this confusion, a discerning review of the published works allows certain limited conclusions to be drawn. Reprocessing of used hemodialyzers changes the biocompatibility profile of a dialyzer as defined by the parameters complement activation. leukopenia, and cytokine release. The effect of reprocessing depends on the chemicals and reprocessing technique applied and also on the type of membrane polymer being subjected to the reprocessing procedure. Reports of pyrogenic reactions indicate that the flux of the membrane also influences how suitable it is for safe reuse. An increased risk of allergic and pyrogenic reactions appears to be associated with dialyzer reuse. Furthermore, there has been a lack of investigations into the immunologic effect of the layer of adsorbed and chemically altered proteins that remains on the inner surface of reprocessed dialyzers. We conclude that the clinical benefit of dialyzer reuse cannot be generally accepted from a biocompatibility point of view.     

The analgesic effect of racemic ketamine in patients with chronic ischemic pain due to lower extremity arteriosclerosis obliterans

Background : Ketamine in sub-dissociative doses has been shown to have analgesic and phantom-Limb pain, where conventional treatment has often failed. Chronic ischemic pain due to lower extremity arteriosclerosis obliterans often responds poorly to analgesics, and the pain-generating mechanisms are not well understood.
Methods : Eight patients with rest pain in the lower extremity due to arteriosclerosis obliterans were given sub-dissociative doses of 0.15, 0.30, or 0.45 mg/kg racemic ketamine and morphine 10 mg as a 5-min infusion on four separate days in a cross-over, double-blind, randomised protocol. Plasma levels of (S)- and (R)-ketamine and their nor-metabolites were analysed with an enantioselective high-performance liquid chromatography (HPLC) method. Pain levels were evaluated with a visual analogue scale (VAS).
Results : Individual pain levels were highly variable during and after all the infusions but the pooled pain levels showed a dose-dependent analgesic effect of ketamine with a transient but complete pain relief in all patients at the highest dose (0.45 mg/ kg). Side-effects, mainly disturbed cognition and perception, were pronounced and dose-dependent. Morphine 10 mg had an analgesic peak at 20 min and 5/8 patients had complete pain relief. The remaining 3 patients also had high baseline pain scores, indicating a higher analgesic potency for the 0.30 and 0.45 mg/ kg ketamine doses than for morphine 10 mg.
Conclusion : We have demonstrated a potent dose-dependent analgesic effect of racemic ketamine in clinical ischemic pain. Due to a narrow therapeutic window, this analgesic effect is probably best utilised in combination with other analgesics.     

Intravenous endotoxin does not increase tissue extravasation of albumin in rats

Background : It is unclear whether activation of the inducible nitric oxide synthase (iNOS) increases or decreases the extravasation of plasma.
Methods : Chloralose anaesthetised male Wistar rats received E. coli lipopolysacharide (LPS), 3 mg kg^-1 i.v., or the corresponding volume of saline, 3 or 5 h before the end of the experiment. Mean arterial pressure (MAP) and heart rate (HR) were recorded. Tissue clearance of radio-labelled albumin, during the last 2 h of each experiment, was determined by a double-isotope method. In separate animals, the serum concentration of nitrite and nitrate was determined, 5 h after LPS or the solvent.
Main Results : LPS initially decreased MAP and lastingly increased HR. In the 3-h LPS animals (n=8), tissue plasma clearance was lower in the heart and calf muscle and increased only in diaphragm, compared to corresponding control animals (n=8). In the 5-h LPS rats, clearance was lowered (n=8) in the entire gastrointestinal tract and in testes, compared to controls (n=8). The serum nitrite/nitrate concentration was higher in animals given LPS (n=6) than in controls (n=6).
Conclusion : After LPS, tissue clearance of albumin was not increased in any major tissue, in spite of increased serum levels of NO end products. Apparently, after activation of iNOS, the augmented release of NO is not necessarily associated with increased albumin extravasation.     

Adrenaline markedly improves thoracic epidural analgesia produced by a low-dose infusion of bupivacaine, fentanyl and adrenaline after major surgery: A randomised, double-blind, cross-over study with and without adrenaline

Background: Basic pharmacological research indicates that there are synergistic antinociceptive effects at the spinal cord level between adrenaline, fentanyl and bupivacaine. Our clinical experience with such a mixture in a thoracic epidural infusion after major surgery confirms this. The objectives of the present study were to evaluate the effects on postoperative pain intensity, pain relief and side effects when removing adrenaline from this triple epidural mixture. Methods: A prospective, randomised, double-blind, cross-over study was carried out in 24 patients after major thoracic or abdominal surgery. Patients with only mild pain when coughing during a titrated thoracic epidural infusion of about 10 ml · h^?1 of bupivacaine 1 mg · ml^?1, fentanyl 2 μg · ml^?1, and adrenaline 2 μg · ml^?1 were included. On the 1^st and 2^nd postoperative days each patient was given a double-blind epidural infusion, at the same rate, with or without adrenaline. The effect was observed for 4 h or until pain when coughing became unacceptable in spite of a rescue analgesic procedure. Rescue analgesia consisted of up to two epidural bolus injections per hour and i.v. morphine if necessary. All patients received rectal paracetamol 1 g, every 8 h. Fentanyl serum concentrations were measured with a radioimmunoassay technique at the start and end of each study period. Main outcome measures were extent of sensory blockade and pain intensity at rest and when coughing, evaluated by a visual analogue scale, a verbal categorical rating scale, the Prince Henry Hospital pain score, and an overall quality of pain relief score. Results: The number of hypaesthetic dermatomal segments decreased (P <0.001) and pain intensity at rest and when coughing increased (P <0.001) when adrenaline was omitted from the triple epidural mixture. This change started within the first hour after removing adrenaline. After 3 h pain intensity when coughing had increased to unacceptable levels in spite of rescue analgesia (epidural bolus injections and i.v. morphine). Within 15–20 min after restarting the triple epidural mixture with adrenaline, pain intensity was again reduced to mild pain when coughing. Serum concentration of fentanyl doubled from 0.22 to 0.45 ng · ml^?1 (P <0.01), and there was more sedation during the period without adrenaline. Conclusions: Adrenaline increases sensory block and improves the pain-relieving effect of a mixture of bupivacaine and fentanyl infused epidurally at a thoracic level after major thoracic or abdominal surgery. Serum fentanyl concentrations doubled and sedation increased when adrenaline was removed from the epidural infusion, indicating more rapid vascular absorption and systemic effects of fentanyl.