犬骨髓间叶干细胞的分离培养和生物学特性

目的 建立犬骨髓间叶干细胞的体外分离、培养、扩增与鉴定方法，了解其生物学特性，为心肌梗死、心力衰竭及缓慢性心律失常的干细胞移植提供细胞材料。方法 抽取犬骨髓液10ml，以DMEM1：1稀释，用1.063g／ml percoll密度分离液，以600g离心力、30min分离骨髓单个核细胞；以LG-DMEM及10% FBS添加100U／ml青霉素，100μg／ml链霉素，25μg／ml两性霉素B培养骨髓干细胞；利用细胞贴壁筛选法分离、培养、扩增骨髓间叶干细胞；应用干细胞表面标志蛋白检测，诱导剂诱导分化间叶组织细胞等方法进行犬骨髓间叶干细胞的鉴定。结果 分离出的犬骨髓单个核细胞约占细胞总数的10^-4～10^-6，在LG-DMEM与选择性血清培养基上生长良好。犬骨髓间叶干细胞孵育24h即可见细胞贴壁生长，贴壁细胞约占接种单个核细胞总数的10^-6。犬骨髓间叶干细胞增殖分裂迅速，38～48h内增殖多个细胞，约72h即可增殖形成大的细胞克隆，7～1Od即可布满瓶底。细胞融合时类似成纤维细胞，呈纺锤状，细胞小而密集，螺旋梳状排列。连续培育10代以上，未见细胞形态、增殖特性发生改变。未见骨髓间叶干细胞自发分化其它类型细胞，仍维持原代培养细胞的增殖特性。犬骨髓间叶干细胞的表面标志SH2阳性，CD45则阴性。在化学诱导液的作用下，犬骨髓间叶干细胞能定向分化为心肌细胞、脂肪细胞、成骨细胞等多种间叶组织类型细胞。结论 密度梯度分离法与贴壁筛选法能较好地进行犬骨髓间叶干细胞的体外分离、培养与扩增，犬骨髓间叶干细胞具备易于分离培养，巨大增殖潜力，独特细胞表型，多系分组能力等细胞生物学特性。为心肌梗死、心力衰竭与心律失常的细胞移植修复治疗提供了理想细胞材料。     

大鼠骨髓间充质干细胞的分离、培养和鉴定

目的 探讨体外分离和培养大鼠骨髓间充质干细胞(MSCs)的生物学特性,对其表型和生长曲线进行初步鉴定.方法 采用全骨髓培养法提取培养MSCs,绘制原代及三代细胞生长曲线,利用免疫组化法检测表面标志物CD34、CD44;流式细胞分析法检测表面标志物CD90.结果 成功培养出MSCs,免疫组化CD44阳性表达,CD34阴性表达;流式细胞术CD90阳性表达.结论 该实验分离培养的细胞群与MSCs的生物学特性相吻合,说明MSCs易于体外分离、培养和扩增.     

成人骨髓间充质干细胞的纯化及部分生物学特性的研究

目的探讨成人骨髓间充质干细胞(bone marrow mesenchymal stem cells或bone maglow stroma cells，MSCs)体外纯化的方法，观察其生物学特性，为其在风湿病治疗中应用提供了初步实验体系和依据。方法抽取健康正常人骨髓3-5ml，Percoll分离液分离后低糖达氏修正依氏培养基(LG—DMEM)培养，流式细胞仪检测表面标记物与细胞周期，绘制生长曲线，并对长时间培养的传代细胞行碱性磷酸酶(AKP)染色及Von Kossa染色。结果①经分离出的细胞为MSCs；②经自然纯化。第2代细胞(P2)与第3代细胞(P3)均质性分别达90％及98％以上；③纯化后，细胞在第3代(P3)细胞增生旺盛，第7代(P7)后细胞呈增长缓慢趋势；④MSCs长期培养，有向成骨细胞分化的趋势。结论利用MSCs特性，经自然纯化．是当前纯化MSCs的一种较好且行之有效的方法。     

巴马香猪骨髓间充质干细胞的分离扩增及初步鉴定

目的 建立巴马香猪骨髓间充质干细胞(mesenchymal stem cells,MSCs)分离、培养、扩增的方法,并进行鉴定.方法 采用梯度离心法分离并结合贴壁筛选法传代纯化培养猪的MSCs;采用倒置相差显微镜观察MSCs的形态学特征;流式细胞仪检测第3代细胞表面标志抗原CD71、CD34的表达率.结果 原代培养的MSCs于6 h后贴壁,贴壁细胞呈集群生长趋势.培养7～9 d后可见细胞融合,14～21 d达到95%融合.第3代细胞表面标记物CD71阳性率为95%,CD34阳性率为0%.结论 采用全骨髓梯度离心法分离并结合贴壁筛选法能够成功分离和培养巴马香猪的MSCs,在第3代可获得高纯度MSCs.     

老龄兔骨髓间充质干细胞体外培养影响因素的研究

目的研究体外培养老龄兔骨髓间充质干细胞(MSCs)的影响因素。方法以密度梯度离心技术及贴壁筛选法相结合,在体外分离检测MSCs表面CD29、CD34、CD44、CD45的表达;诱导分化反向证明部分细胞可分化为成骨细胞及脂肪细胞,具有分化潜能,鉴定该细胞群为干细胞。细胞记数法计算MSCs倍增时间;观察供体自然老龄情况下,不同换液时间、不同血清浓度、不同种植密度等因素对MSCs生长的影响。结果MSCs CD29和CD44表达阳性,不表达造血干细胞标志CD34和CD45。高密度接种(3×106~4×106个/cm2),低浓度(8%~10%)血清的低糖DMEM培养,在体外可保持MSCs未分化增殖状态,并获得纯度较高同源性较好的干细胞群,高浓度血清(20%)并不加速细胞生长,而促进分化。结论MSCs具有体外多分化潜能,老龄供体骨髓中MSCs的生长、增殖特性受不同换液时间、不同血清浓度及不同种植密度等因素的影响。     

大鼠骨髓间充质干细胞的分离培养及生物学特性

用密度梯度离心结合贴壁培养法分离纯化大鼠骨髓间充质干细胞(MSCs),体外培养传代扩增,观察细胞生长特性,对细胞进行免疫组化染色鉴定,电镜观察细胞形态。动态观察示培养细胞具有不断增殖的干细胞特性,并保持细胞活性。证实密度梯度离心结合贴壁法以及消化传代能有效分离纯化和扩增骨髓MSCs,培养的细胞具有骨髓MSCs的基本表型和特性。本研究可为临床进行细胞移植奠定基础。     

胎肝来源间充质干细胞的分离、培养与多向分化

目的从胎肝中分离培养间充质下细胞，并研究其牛物学特性。方法用优化的方法从胎肝中分离获得间充质干细胞。利用流式细胞仪分析细胞表型和细胞周期分布，并体外诱导成骨、成脂肪和成肝组织细胞分化。并用染色方法鉴定成骨、成脂肪分化结合形态学方法和RT-PCR方法鉴定成肝组织分化结果。结果从胎肝中分离培养的细胞为成纤维样，贴壁生长．表型相对均一，表面标志为CD90，CD44，CD147，而CD34，CD45，HLA-DR，具有向肝组织分化的潜能，并可向成骨和成脂肪分化。结论从胎肝中可分离培养得到具有多向分化潜能的间充质干细胞。     

大鼠骨髓间充质干细胞体外分离培养及生物学特性研究

目的建立大鼠骨髓间质干细胞（mesenchymal stem cells，MSCs）体外分离、纯化及扩增的方法及对大鼠MSCs的生物学特性进行研究。方法采用贴壁筛选法分离大鼠MSCs，并通过不断传代进行纯化和扩增培养，检测大鼠MSCs生长周期，绘制细胞生长曲线。结果大鼠MSCs在体外分离培养扩增，大鼠MSCs形态呈长梭形，细胞周期显示第3代MSCs约有81．48％的细胞处于G0／G1期，细胞生长曲线呈S形。结论所建立的分离和培养方法获取的大鼠MSCs具有生物学特性。     

MRL/lpr鼠骨髓间充质干细胞对T淋巴细胞作用的研究

目的 探讨狼疮鼠（MRL／lpr）及正常鼠（C57BL／6）骨髓间充质干细胞（MSCs）体外生物学特性、对T淋巴细胞作用的影响。方法 采用直接贴壁筛选法分离培养扩增两种鼠系骨髓MSCs，流式细胞术鉴定MSCs表面标记物，观察MSCs生长状况并绘制生长曲线；取C57BL／6鼠脾脏细胞，经尼龙毛柱分选CD3T淋巴细胞．经刀豆蛋白A（ConA）刺激，取正常及狼疮鼠MSCs或MSCs培养上清与T细胞共培养72h，然后羧基荧光素二醋酸盐琥珀酰亚胺酯（CFSE）染色测定T细胞增殖，流式细胞术检测共培养前后T细胞活化及T细胞的凋亡率。结果 第2代（P2）后狼疮鼠MSCs生长增殖快于正常鼠MSCs；正常及狼疮鼠MSCs共培养均可抑制正常鼠T细胞的增殖（P〈0．05），与MSCs上清共培养对正常鼠T细胞增殖无抑制作用（P〉0．05）；与两种MSCs或上清共培养均可降低正常T细胞的活化（P〈0．05）及凋亡率（P〈0．05）。对正常T细胞增殖、活化、凋亡的影响，狼疮鼠MSCs与正常鼠MSCs间差异无统计学意义（P〉0．05）。结论 狼疮鼠MSCs在体外生长上存在异常．但对T细胞增殖、活化、凋亡免疫调节无异常。     

大鼠骨髓间充质干细胞体外诱导分化为神经元样细胞的初步研究

目的探讨体外培养、扩增骨髓间充质干细胞(MSCs)的方法,诱导MSCs向神经元样细胞定向分化。方法取大鼠骨髓,采用贴壁培养筛选法分离MSCs,进行培养扩增,观察其生物学特性;用IBMX诱导MSCs向神经元样细胞分化,并通过细胞免疫化学法鉴定分化细胞。结果大鼠MSCs可通过贴壁法成功分离,并可在体外大量扩增,经IBMX诱导,MSCs可向神经元样细胞分化,出现胞体和突起,细胞免疫化学染色神经元特异性烯醇化酶和巢蛋白呈阳性。结论MSCs易分离和培养,体外培养条件下生长良好,可连续传代,诱导剂作用下可分化出神经元样细胞。     

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.     

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.     

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.     

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.