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1.
目的探讨胶原凝胶包埋软骨细胞复合聚磷酸钙纤维/左旋聚乳酸(CPPf/PLLA)支架异体移植修复兔关节软骨缺损的有效性和可行性。方法将胶原凝胶包埋的软骨细胞接种CPPf/PLLA支架构建的复合物体外培养3周,行倒置显微镜和扫描电镜观察,并将复合物异体移植入兔关节软骨缺损,术后4、8、12周取材,从大体、组织学和Ⅱ型胶原免疫组织化学对再生软骨组织进行评价。结果复合物体外培养3周,细胞被大量基质包裹,在支架内分布均匀;新形成的组织为透明软骨样组织、表面光滑且与周围组织整合良好、基质内有Ⅱ型胶原分布。结论胶原凝胶包埋软骨细胞接种CPPf/PLLA支架的方法能提高细胞一支架复合物构建质量,胶原凝胶复合CPPf/PLLA支架可作为软骨细胞载体修复关节软骨缺损。  相似文献   

2.
目的:探讨软骨细胞均匀、高效种植于三维支架的细胞接种方法.方法:将胶原凝胶包埋的软骨细胞整合入CPPf/PLLA三维支架并进行体外培养,细胞计数检测细胞粘附情况,倒置显微镜观察细胞在支架内分布的均一性,组织形态学检测细胞-胶原凝胶-支架复合物形成软骨组织的情况.结果:超过90%的种植细胞能有效、均匀种植于CPPf/PLLA支架,体外培养3周的复合物能形成较成熟的工程化软骨组织.结论:胶原凝胶包埋软骨细胞三维接种能有效提高组织工程软骨的体外构建质量,同时结合了两种材料的优势.  相似文献   

3.
目的:探讨软骨细胞均匀、高效种植于三维支架的细胞接种方法。方法:将胶原凝胶包埋的软骨细胞整合入CPPf/PLLA三维支架并进行体外培养,细胞计数检测细胞粘附情况,倒置显微镜观察细胞在支架内分布的均一性,组织形态学检测细胞-胶原凝胶-支架复合物形成软骨组织的情况。结果:超过90%的种植细胞能有效、均匀种植于CPPf/PLLA支架,体外培养3周的复合物能形成较成熟的工程化软骨组织。结论:胶原凝胶包埋软骨细胞三维接种能有效提高组织工程软骨的体外构建质量,同时结合了两种材料的优势。  相似文献   

4.
骺板软骨细胞复合三维支架体外构建组织工程软骨的研究   总被引:6,自引:0,他引:6  
目的探讨将骺板软骨细胞复合三维支架经体外培养,构建组织工程软骨的效果及其生物学特点. 方法将3周龄幼兔第1代骺板软骨细胞与液态的生物凝胶混合,接种于聚磷酸钙纤维/L-聚乳酸(CPPF/PLLA)三维支架材料,构建组织工程软骨组织块,连续培养4周.行大体、倒置显微镜及组织学、Ⅰ型和Ⅱ型胶原免疫组织化学光镜观察,定量检测硫酸糖胺多糖(GAG)含量. 结果构建的组织工程软骨块在培养过程中能保持其初始外形,种子细胞呈稳定的三维均相分布,外观逐渐呈乳白色、半透明,硬度亦不断增加.培养1周有软骨细胞陷窝形成,2周后形成富含Ⅱ型胶原和蛋白聚糖、具有典型软骨组织结构的工程化软骨,且Ⅰ型胶原逐渐转为阴性.4周时构建软骨的组织结构与天然骺板软骨相类似,硫酸GAG含量平均为天然骺板软骨的34%以上. 结论骺板软骨细胞复合三维支架体外培养可生成典型软骨,且可形成类似天然骺板软骨的组织结构,能满足修复骺板缺损的基本要求.体外培养1~2周可能是植入体内修复骺板缺损的较佳时机.  相似文献   

5.
[目的]探讨补肾行气活血法在骨髓基质于细胞诱导软骨细胞修复兔关节软骨缺损中的作用. [方法]将胶原凝胶包埋的骨炎定含药血清培养的骨髓基质干细胞诱导的软骨细胞和异体软骨细胞接种CPPf/PLLA支架构建的复合物体外培养3周,行倒置显微镜和扫描电镜观察,并将复合物异体移植入兔关节软骨缺损,术后4、8、12周取材,从大体、组织学和Ⅱ型胶原免疫组织化学分别对再生软骨组织进行评价. [结果]诱导软骨细胞组在支架内分布均匀、透明软骨样组织的形成、表面光滑度、与周围组织整合程度及基质内有Ⅱ型胶原分布等方面明显优于软骨细胞组. [结论]补肾行气活血法在关节软骨缺损修复的作用中较传统的方法有其优越性.  相似文献   

6.
目的:应用组织工程学技术,体外初步构建组织工程化人工关节软骨。方法:制备三维多孔软骨支架材料CPP/PLLA,体外诱导兔MSCs向软骨细胞表型分化,免疫组织化学染色检测软骨特异性Ⅱ型胶原表达,将诱导细胞与软骨支架材料CPP/PLLA复合,体外培养构建人工关节软骨,1周后终止培养,扫描电镜观察组织工程化人工软骨的微观结构;同时将构建人工软骨移植于兔大腿皮下,3周后处死动物,甲苯胺蓝染色观察。结果:扫描电镜观察可见该复合材料CPP/PLLA为高孔隙率的网状、连通、微孔结构,微孔分布均匀,孔径大小为300~400μm之间;兔MSCs经体外软骨表型定向诱导后,Ⅱ型胶原免疫组化染色阳性。诱导后的MSCs可在支架材料内良好贴附生长,细胞被分泌的胶原基质包裹;从体内获取的培养物组织切片观察可见大量的软骨细胞生成,甲苯胺蓝染色阳性。结论:经软骨起源诱导后的MSCs与CPP/PLLA复合培养可以构建自体软骨移植的替代物,为应用软骨组织工程方法修复关节软骨缺损和功能重建提供一种新材料,具有较大的潜在应用价值。  相似文献   

7.
目的应用组织工程学技术,体外初步构建组织工程化人工关节软骨。方法制备三维多孔软骨支架材料CPP/PLLA,体外诱导兔MSCs向软骨细胞表型分化,免疫组织化学染色检测软骨特异性Ⅱ型胶原表达,将诱导细胞与软骨支架材料CPP/PLLA复合,体外培养构建人工关节软骨,1周后终止培养,扫描电镜观察组织工程化人工软骨的微观结构;同时将构建人工软骨移植于兔大腿皮下,3周后处死动物,甲苯胺蓝染色观察。结果扫描电镜观察可见该复合材料CPP/PLLA为高孔隙率的网状、连通、微孔结构,微孔分布均匀,孔径大小为300~400Ⅳn之间;兔MSCs经体外软骨表型定向诱导后,Ⅱ型胶原免疫组化染色阳性。诱导后的MSCs可在支架材料内良好贴附生长,细胞被分泌的胶原基质包裹;从体内获取的培养物组织切片观察可见大量的软骨细胞生成,甲苯胺蓝染色阳性。结论经软骨起源诱导后的MSCs与CPP/PLLA复合培养可以构建自体软骨移植的替代物,为应用软骨组织工程方法修复关节软骨缺损和功能重建提供一种新材料,具有较大的潜在应用价值。  相似文献   

8.
组织工程骺板软骨移植修复兔胫骨上骺板缺损   总被引:4,自引:2,他引:2  
目的 探讨在体外以三维支架构建的组织工程骺板软骨修复胫骨上骺板缺损的效果 ,了解促进植入工程化软骨与受区骺板融合方法的效果。 方法 酶消化分离幼兔骺板软骨细胞并接种培养 ,收获第 1代软骨细胞 ,制成 2 .5× 10 7/ ml的细胞凝胶混悬液 ,接种于聚磷酸钙纤维 / L-聚乳酸 (CPPf/ PL L A)复合支架体外构建组织工程化软骨。采用幼兔右侧胫骨上骺板 4 0 %缺损模型 ,将日本大耳白兔 72只分为 4组 ,每组 18只 :A组缺损区植入同窝幼兔来源的工程化软骨 ,并以相同的细胞凝胶混悬液充填其间隙 ;B组充填复合有生物凝胶而无细胞的 CPPf/ PL L A支架材料 ;C组植入皮下脂肪 ;D组不做任何充填。分别于术后 2、4、6、8、12和 16周摄 X线片、大体及组织学观察。 结果 A组术后2周组织工程化软骨在骺板缺损区即衍生为典型的骺板组织结构 ,并与受区骺板组织很好融合 ;4周修复骺板组织 ,结构正常、胫骨无畸形 ;8周后骺板修复区出现早闭的组织学表现 ,胫骨出现短缩和内翻畸形 ;16周修复区骺板已闭合 ,胫骨畸形明显 ,生长功能恢复率为 4 3.6 %。B、C、D3组术后 2周胫骨即出现畸形 ;4周骺板缺损区均已骨性闭合 ,畸形明显 ;16周畸形严重。后三组间差异无统计学意义 ,骺板缺损区无骨生长。 结论 组织工程化的骺板软骨  相似文献   

9.
目的 探讨胶原凝胶包埋软骨细胞接种BCM支架的三维培养对软骨细胞生长及功能的影响.方法 将胶原凝胶包埋的关节软骨细胞接种BCM支架并在体外培养,应用倒置相差显微镜和扫描电镜观察软骨细胞的粘附、生长和增殖情况,培养14d,行苏木精-伊红、甲苯胺蓝染色观察软骨组织形成情况.结果 软骨细胞在支架上粘附、生长和增殖良好,体外培养14d能形成较成熟的软骨组织.结论 胶原凝胶复合BCM支架具有良好的细胞相容性,可作为负载生长因子的载体.  相似文献   

10.
人组织工程软骨的实验研究   总被引:2,自引:0,他引:2  
目的 了解组织工程研究的基本原理 ,完善制作组织工程化人软骨的技术方法 ,探讨天然可吸收材料组织 ,引导再生胶原膜作为人软骨细胞体外培养支架的可行性 ,为广泛开展组织工程的研究与应用开辟新的途径。方法 利用组织工程技术制作人组织工程化软骨 ,并应用组织学方法 ,对获得的人组织工程化组织形态和功能进行表征。结果 培养的软骨细胞均匀沉降于医用组织引导再生胶原膜上 ,1周后形成一层乳白色软骨样组织 ;植入 8周后从裸鼠体内获得软骨样组织 ,组织学检测证实软骨细胞的存在 ,软骨细胞可以分泌硫酸软骨素。结论 医用组织引导再生胶原膜以其特有的三维结构和细胞网结功能 ,可以作为组织工程技术应用研究中软骨细胞培养的支架 ;利用组织工程技术 ,能够完成人组织工程化软骨的制作。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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 1st and 2nd 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.  相似文献   

18.
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.  相似文献   

19.
Enteral feeding is often limited by gastric and intestinal motility disturbances in critically ill patients, particularly in patients with shock. So, promotility agents are frequently used to improve tolerance to enteral nutrition. This review summaries the pathophysiology, presents the available pharmacological strategies, the clinical data, the counter-indications and the principal limits. The clinical data are poor. No study demonstrates a positive effect on clinical outcomes. Metoclopramide and erythromycin seems to be the more effective. Considering the risk of antibiotic resistance, the first line use of erythromycin should be avoided in favor of metoclopramide.  相似文献   

20.

Introduction

The practice of pediatric anesthesia requires a regular update of scientific knowledge and technical skills. To provide the most adequate Continuing Medical Education programs, it is necessary to assess the practices of pediatric anesthesiologists. Thus, the objective of this survey was to draw a picture of the current clinical practices of general anesthesia in children, in France.

Material and methods

One thousand one hundred and fifty questionnaires were given to anesthesiologists involved in pediatric cases. These questionnaires collected information on various aspects of clinical practice relative to induction, maintenance, recovery from general anaesthesia and also classical debated points such as children with Upper Respiratory Infection (URI), emergence agitation, epileptoid signs or anaesthetic management of adenoidectomy. Differences in practices between CHG (general hospital), CHU (teaching hospital), LIBERAL (private) and PSPH (semi-private) hospitals were investigated.

Results

There were 1025 questionnaires completed. Fifty-five percent of responders worked in public hospitals (CHG and CHU); 77% had a practice that was 25% or less of pediatric cases. In children from 3 to 10 years: 72% of respondents used always premedication and two thirds performed inhalation induction in more than 50% of cases. For induction, 53% used sevoflurane (SEVO) at 7 or 8%. Respondents from LIBERAL used higher SEVO concentrations. Tracheal intubation was performed with SEVO alone (37%), SEVO and propofol (55%) and SEVO with myorelaxant (8%), 93% of respondents used a bolus of opioid. For maintenance, the majority of respondents used SEVO associated with sufentanil; desflurane and remifentanil were more frequently used in CHU. Two thirds of respondents used N2O. Depth of anesthesia was commonly assessed by hemodynamic changes (52%), end tidal concentration of halogenated (38%) or automated devices based on EEG (7%). In children with URI, 98% of respondents used SEVO for anesthesia. To control the airway 42% used a tracheal tube, 30% a laryngeal mask and 20% a facial mask. Emergence agitation was an important concern for two thirds of respondents, while epileptoid signs were considered as important by only 20%. Eighty-nine percent of respondents practiced anesthesia for adenoidectomy. Anesthesia was induced by inhalation of SEVO 7–8% (41%), 6% (39%) or 4% (12%), 66% put an intravenous line (less frequently in LIBERAL). 67% of the responders managed adenoidectomy without any device to control the airway (more frequently in LIBERAL), 32% administrated a bolus of opioid (less frequently in LIBERAL).

Discussion

This survey demonstrated that the practices regarding general anesthesia in children are relatively homogenous. Most of the differences appeared between LIBERAL and the others structures; the anaesthetic management for adenoidectomy illustrates these findings.  相似文献   

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