应用同种异体组织工程软骨修复关节软骨缺损观察

目的用胶原蛋白和人血纤维蛋白混合物为载体支架在体外进行软骨细胞三维立体培养,构建人工软骨组织,利用此人工软骨修复关节软骨缺损。方法取2周龄兔关节软骨,经消化、分离的软骨细胞体外培养。培养第3周时,进行免疫组织化学分析;利用培养3周的人工软骨对异体成兔的关节软骨损伤进行修复。结果培养物内软骨细胞均得到较好存活,形成软骨陷窝,出现同源性细胞簇,分泌软骨基质;DNA和糖胺多糖(GAG)在培养第24天时达到高峰,分别为(5.18±0.19)、(214.3±2.8)μg/块;对异体关节软骨损伤的移植修复结果良好,在12周时,移植物与周边正常组织结合紧密、齐高,移植的软骨细胞趋于柱状排列,为透明软骨组织。结论用胶原蛋白和人血纤维蛋白为载体支架体外培养软骨细胞,可构建较大的组织工程软骨,能较好地修复同种异体关节软骨缺损。     

应用人胚软骨细胞修复关节软骨缺损的研究

目的了解应用人胚胎关节软骨细胞修复家兔膝关节软骨大面积深层缺损的效果,为临床上进一步应用人胚胎关节软骨细胞进行同种异体细胞移植的可行性提供佐证.方法将分离的人胚胎关节软骨细胞以天然胶原作为细胞外基质网架,进行体外三维培养1周后,植入家兔关节软骨大面积深层(5 mm×5 mm×4 mm)缺损处,对修复组织进行大体观察及组织学评估.结果移植术后12周,缺损部位平坦、光滑,已为类似关节软骨的半透明组织填充,修复组织与宿主关节软骨组织整合较好,界限模糊;移植术后24周,缺损表面为透明软骨填充,缺损深部的软骨下骨组织已经重建.结论人胚胎关节软骨细胞可以作为软骨组织工程的种子细胞用于修复关节软骨组织的缺损.     

同种异体骨骨髓基质细胞复合物联合VEGF对兔桡骨缺损愈合的影响

目的 观察同种异体骨骨髓基质细胞复合物联合VEGF局部应用对兔桡骨缺损愈合的影响.方法 以新西兰白兔松质骨为同种异体骨,取4月龄新西兰白兔红骨髓,分离、培养骨髓基质细胞,制备同种异体骨骨髓基质细胞复合物.另取新西兰白兔36只,制作桡骨缺损模型.随机分为A、B、C组,每组12只.A组植入同种异体骨骨髓基质细胞复合物,局部应用VEGF;B组只植入同种异体骨骨髓基质细胞复合物;C组植入同种异体松质骨(兔松质骨).分别于术后2、4、8、12周通过X线检查、组织学检查观察三组动物骨缺损愈合情况,术后12周采用万能实验机通过三点弯曲试验,测定骨缺损愈合处的桡骨弯矩和最大应力.结果 术后2、4、8、12周X线检查及组织学检查示A组骨形成及塑形情况均优于B组,B组优于C组.A、B、C组术后12周兔桡骨弯矩分别为( 82.55±6.29)、(70.22±5.11)、(66.13±5.07)N·cm,桡骨最大应力分别为(45.39±8.16)、( 35.28±8.67)、(27.53±9.40) Mpa,三组相比,P均＜0.05.结论 同种异体松质骨骨髓基质细胞复合物联合VEGF局部应用可明显促进兔桡骨缺损愈合,效果优于单用同种异体松质骨骨髓基质细胞复合物及同种异体骨.     

组织工程软骨修复全层大面积关节软骨损伤的实验研究

目的观察由软骨细胞体外培养的人工软骨组织对家兔膝关节软骨全层缺损修复的可行性.方法分离收集兔软骨细胞(4周龄),用培养液悬浮,经离心管体外培养成组织工程软骨,然后植入兔膝关节股骨负重面的缺损(5 mm×4 mm)部位,观察2,4,8,12周软骨缺损的修复情况,并进行大体和组织学观察.结果移植后第8周,移植部位填充物与宿主已完全整合,缺损处表面光滑;组织学显示,缺损部位新生软骨与所移植软骨有较好的连续性,并且缺损底部有软骨下骨及海绵状骨生成;对照组(未移植组),从组织学观察到缺损部位呈纤维样修复,未见有由新生软骨细胞形成软骨组织.结论用体外培养的组织工程软骨做移植物修复家兔关节软骨组织深层缺损具有较好的疗效.     

生长因子与软骨细胞-胶原海绵复合体联合应用修复软骨缺损的研究

目的研究在体条件下碱性成纤维生长因子（bFGF）与软骨细胞-胶原海绵复合体联合应用修复软骨缺损的疗效. 方法取3日龄异体幼兔膝关节软骨细胞,体外培养后接种在胶原海绵支架上,再做移植.同一大白兔双侧膝关节内外髁分为4组：空白对照组、软骨细胞-胶原海绵复合体移植组（复合体移植组）、bFGF应用组和软骨细胞-胶原海绵复合体与bFGF联合应用组.移植术后不同时间分批处死,进行大体、光镜和电镜观察. 结果移植术后12周联合应用组软骨缺损修复以完全修复为主,而复合体移植组以不完全修复为主,差异有统计学意义;20周时2组均得到修复,差异无统计学意义,组织学分析均为软骨组织;在不同时间点空白对照组和单纯bFGF应用组软骨缺损修复差异无统计学意义,但组织学上修复的组织,前者为纤维组织,而后者同时有软骨组织存在. 结论 bFGF在软骨组织工程中有促进软骨缺损早期修复的作用.     

关节软骨组织体外保存力学环境构建

<正>目前多种治疗方法运用于关节软骨缺损的修复,但大多数疗效不理想,修复组织也以纤维软骨为多,缺乏正常透明软骨的生物力学性能及耐用性。同种异体骨软骨移植术是将供体关节的活性骨软骨块移植到受体关节软骨及软骨下骨缺损区,以修复关节软骨损伤〔1,2〕。患者软骨缺损区完全被透明软骨修复;关节软骨细胞完全包埋在周围软骨基质中,为"免疫豁免"组织。关节软骨是一种特殊的结缔组织,表面光滑位于骨两端关节面位置,在骨与骨间的关节处为其活动提供低磨损和摩擦     

组织工程软骨修复兔膝关节软骨大面积深层缺损的实验研究

目的　将培养的软骨细胞埋在胶原凝胶中,观察其对家兔漆关节软骨大面积深层缺损的修复作用。方法体外培养软骨细胞,然后与胶原以一定比例混合培养,植入免膝关节股骨负重面的缺损（５ｍｍ ×４ｍｍ）部位,观察 ２、４、８．１２周软骨缺损的修复情况,并进行大体和组织学观察。结果移植后第 ８周,所修复组织的边缘变得模糊,与周围宿主整合得很好,缺损边缘不清晰。组织学观察,缺损处表面光滑,边缘与宿主完全整合,缺损处呈典型的关节软骨样组织,并且底部有新形成的软骨及骨小梁生成。对照组（未移植组）组织学观察缺损部位主要为纤维组织所填充,未见有由新生软骨细胞形成的软骨组织。结论埋在胶原凝胶中软骨细胞对家兔膝关节软骨深层缺损的修复作用。     

应用自体软骨细胞移植物修复关节软骨缺损

目的 通过体外扩增关节软骨细胞，构建软骨组织工程移植物，观察移植物对自体关节软骨损伤的修复作用。方法 由8周龄成年兔髌骨外侧缘获取关节软骨，分离软骨细胞，体外扩增后，与牛Ⅰ型胶原、人血冻干纤维蛋白原、凝血酶按一定比例混合，制成软骨培养物，体外培养4d。用于对成兔自体关节软骨损伤的移植修复。结果 成年家兔关节软骨细胞体外单层培养至第2代时开始出现去分化现象，可利用生长因子抑制去分化；该移植物的移植修复效果良好，修复后12周移植物与周边正常组织结合紧密、齐高，细胞趋于柱状排列，已形成透明软骨组织。结论 利用体外扩增的方法能获得足够量表型良好的关节软骨细胞，当应用胶原-纤维蛋白为载体制备出软骨组织工程培养物后，能较好地修复自体关节软骨损伤。     

成年犬自体骨髓基质干细胞经冠状动脉移植在心梗后心肌组织内分化

目的　探讨经冠状动脉移植成年犬自体骨髓基质干细胞在心梗后心肌组织内的存活、分化情况。方法　结扎犬冠状动脉前降支制备心肌梗死模型 ;细胞移植组将体外培养、诱导的自体骨髓基质干细胞标记后在心肌梗死后 4周经冠状动脉植入心脏 ;对照组植入等量培养基 ;细胞移植 4周后取犬心脏 ,行组织学检查、免疫组织化学检查及电镜检查。结果　细胞移植组植入骨髓基质干细胞在心肌组织内存活 ;免疫组织化学检查结蛋白、肌钙蛋白I染色阳性 ;电镜示心肌疤痕组织中可见胞浆丰富的异源性细胞 ,圆形或椭圆形 ,细胞体积较大 ,核糖体丰富 ,线粒体较丰富 ,有肌丝样结构 ,单核。对照组心脏标本中可见疤痕组织 ;心肌细胞结蛋白染色阴性 ,肌钙蛋白I染色阳性 ;电镜未发现异源性细胞。结论　成年犬骨髓基质干细胞经冠状动脉移植后在心肌组织内存活并分化为肌源性细胞。     

骨关节炎软骨移植的研究进展

骨关节炎是一种常见的关节病 ,以关节软骨的进行性变性和破坏为特征 ,可能与关节软骨生物力学及生物化学尤其是细胞外基质的代谢异常有关。在骨关节炎早期 ,软骨细胞增生及细胞外基质合成增多 ,关节软骨可进行自身修复 ,随着慢性损伤的持续加重 ,蛋白溶解酶合成明显增加而导致关节软骨修复失败。至今改善骨关节炎病情进展的有效方法还十分缺乏 ,而骨软骨和软骨细胞移植则可能是目前较有前途的治疗方法之一。1　软骨的免疫原性一直认为关节软骨为免疫“特惠”组织 ,然而软骨尤其是软骨细胞亦具有抗原性。研究发现兔膝关节对软骨细胞移植物发…     

The immunoneuroendocrine role of melatonin

Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.     

Changes in connexin43, the gap junction protein of astrocytes, during development of the rat pineal gland

Abstract: The abundance of gap junctions between rat pineal astrocytes formed by connexin43 (Cx43) was studied during development. Levels and distribution of Cx43 were measured by immunoblotting and indirect immunofluorescence, respectively. The amount of Cx43 in cells located within the gland was low until about the 7th postnatal day and increased to adult values between the 14th and 21st days postpartum. Although astrocytes, recognized by their vimentin immunoreactivity, were scarce before birth, they were abundant by the 7th postnatal day suggesting that the low levels of Cx43 found at this age corresponded to a low expression of this protein. Localization of the immunoreactivity to Cx43 and vimentin showed a close correlation, indicating that mature or immature pineal astrocytes form gap junctions made of Cx43. Since Cx43 levels attained their adult values at about the time the innervation and the functional state of the gland reached maturity (2–3 weeks after birth), it is proposed that astrocyte gap junctions are involved in the function of the adult rat pineal gland.     

Response of rat pineal melatonin to calcium, magnesium, and lithium is circadian stage dependent

Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.     

Conservative management of perforated duodenal diverticulum： A case report and review of the literature

Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.     

Presence of immunoreactive growth hormone and prolactin in the ovine pineal gland

Abstract: The use of antisera raised against bovine growth hormone (GH) and ovine prolactin (PRL) enabled the detection of related immunoreactive (ir) sequences of proteins in ovine pineal tissue. The isolation of PRL-like ir-material was accomplished using a 0.25 M ammonium sulphate (pH 5.5) extraction followed by ethanol precipitation, whereas the resulting 2.0 M ammonium sulphate (pH 7.0) precipitate contained a GH-like immunoreactivity. Gel chromatography of the GH-like immunoreactivity (Sephadex G-100) indicated the presence of several GH-like fragments ranging in the M_r range of 7,000 to 55,000. Analyses of the PRL-like ir-material found in pineal tissue on HPLC using a TSK 545-DEAE column led to the resolution into a single peak of immunoreactivity. A single peak of activity was also observed following chromatofocusing and hydrophobic interaction chromatography of the ir-peak from the TSK 545-DEAE column. The PRL-like ir-material inhibited the binding of [¹²⁵I]ovine PRL-S14 to anti-ovine PRL antibodies without showing an affinity for binding to anti-rat PRL or anti-bovine GH antibodies. Scatchard analysis of the binding of pineal PRL-like ir-material and pituitary ovine PRL-S14 to liver membranes from day-20 pregnant rats revealed similar affinity constants (K_a of 4.7 ± 0.2 × 10⁹ M^-1). In addition, the replication of Nb 2 Node rat lymphoma cells was stimulated by pineal PRL-like ir-material, an effect known to be specific for lactogenic hormones. The pineal PRL-like immunoreactivity appeared on sodium dodecyl sulfate polyacrylamide gels as a single major band of M_r 24,000. The functional status of PRL-and GH-like ir-material in the ovine pineal remains to be determined, but evidence is presented that the overall protein synthesis rate of the rat pineal responded to circulating concentrations of PRL.     

Microbiology of human immunodeficiency virus anorectal disease

PURPOSE: Individuals who are seropositive for the human immunodeficiency virus are at high risk for opportunistic infection and anorectal disorders. Little prospective information is available regarding anorectal pathogens in these patients. METHODS: One hundred sixty-three HIV-seropositive patients presented to the colorectal clinic between 1989 and 1992. Forty-seven (29 percent) patients were thought to have an infectious process and were prospectively studied using a standardized multiculture protocol. RESULTS: Mean age was 33 (range, 19–59) years. All were male; high-risk behavior accounted for 87 percent of HIV transmissions. Presenting complaints included anorectal pain (79 percent), pus per anum (28 percent), and blood per anum (26 percent). Examination revealed perianal tenderness (60 percent), condyloma (38 percent), perianal ulcers (38 percent), and anal fissures (34 percent). Sixty-six sets of cultures were performed; 28 patients had one set, 15 had two sets, and 4 had three sets. Thirty-two of these 47 patients (68 percent) had positive cultures including herpes (50 percent), cytomegalovirus (25 percent),Neisseria gonorrhoeae (16 percent), chlamydia (16 percent), acidfast bacilli (2 percent), and others (9 percent). Six of 32 patients with positive cultures had more than one organism cultured. Sixteen (50 percent) patients with positive cultures were treated medically, 8 (25 percent) were treated surgically and 8 (25 percent) were treated with both modalities. Sixty-one procedures were performed on 17 patients for condylomata. Eighteen patients had 20 procedures for abscesses, 50 percent of whom had positive cultures for other than common bowel flora; all improved. Fourteen patients underwent 33 procedures for perianal fistulas.Mycobacterium fortuitum was cultured from one patient who required 13 procedures for abscesses and fistulas. Forty-five (96 percent) patients were followed for an average of 12.5 months ±2.9 SEM (range, 1–94 months). Symptoms were improved or resolved in 22 of 32 (69 percent) patients with positive cultures and in 11 of 13 (84 percent) with negative cultures. CONCLUSIONS: Specific pathogens may often be identified in human immunodeficiency virus-seropositive patients with anorectal disorders if aggressively sought. Although patients without specific pathogens identified may be expected to improve with planned empiric treatment, positive identification allows more directed therapy.