HSV-TK+GFP/GCV自杀基因系统对小鼠胰腺癌的治疗作用

目的: 探讨HSV-TK+GFP/GCV自杀基因系统对小鼠胰腺癌细胞系MPC体外及体内杀伤作用及其产生的旁观者效应.方法: 通过RT-PCR从基因组文库中扩增出HSV-TK基因全长CDS序列, 并将其与GFP基因定向克隆到质粒表达载体pcDNA3.1(+), 构建重组质粒pcDNA3.1+/HSV-TK+GFP. 脂质体法将重组质粒转染小鼠胰腺癌细胞株MPC细胞, 得到带有HSV-TK和GFP基因的MPC/HSV-TK+GFP细胞, 并将其分别用于体外和体结果: 重组质粒pcDNA3.1+/HSV-TK+GFP导入小鼠胰腺癌细胞株MPC细胞. 体外实验结果显示, 当MPC/HSV-TK+GFP细胞数占混合细胞10%时, 低浓度(20 mg/L)的GCV就可将50%左右的肿瘤细胞杀死. 体内实验结果显示GCV可明显抑制MPC /HSV-TK+GFP细胞在昆明小鼠体内的肿瘤形成.结论: HSV-TK和GFP基因转入小鼠胰腺癌细胞株MPC细胞并获得稳定表达, HSV-TK+GFP/GCV自杀基因系统在体内外对小鼠胰腺癌均有杀伤作用, 且存在明显的旁观者效应.     

人Midkine启动子驱动的HSV-TK自杀基因体外抗肝癌作用

目的 观察以人Midkine(MK)启动子调控单纯疱疹病毒胸苷激酶基因(HSV-TK)/丙氧鸟苷(GCV)自杀基因系统在体外对人肝癌细胞的杀伤效应.方法 以含有人MK启动子调控的HSV-TK基因的重组腺病毒分别感染体外培养的甲胎蛋白(AFP)阳性人肝癌细胞BEL-7402和AFP阴性人肝癌细胞SMMC-7721,RT-PCR法检测HSV-TK基因在上述两种细胞中的转录表达,观察GCV对人肝癌细胞的杀伤作用.结果 GCV在体外对重组腺病毒感染的BEL-7402及SMMC-7721均有明显的杀伤作用,又以前者为著.相同的病毒滴度,其杀伤作用随着GCV浓度的增高而增强.均具有旁观者效应.结论 在体外表现HSV-TK基因的AFP阳性及阴性人肝癌细胞均可被人MK启动子调控的自杀基因HSV-TK杀伤.     

Ad-HSV-TK/GCV自杀基因系统对人卵巢癌细胞增殖、凋亡的影响

目的 探讨腺病毒介导的单纯疱疹病毒腺苷激酶（HSV-TK）/丙氧鸟苷（GCV）自杀基因系统对人卵巢癌细胞SKOV-3增殖、凋亡的影响.方法 以人卵巢癌细胞SKOV-3为实验组,人成纤维细胞株MRC-5为对照组,两组分别取对数生长期,调整细胞浓度为1×107/mL.采用Ad-hTERT-HSV-TK分别转染两组细胞48 h,然后分别给予不同浓度的GCV（0.1、1、5、10、20、50、100、200 μg/mL）作用48 h.采用MTT法检测各组OD值,计算并比较两组细胞增殖率、凋亡率.结果 5、10、20、50、100、200 μg/mL GCV作用下实验组细胞增殖率较对照组降低（P＜0.05）,实验组GCV 10、100 μ/mL作用下细胞凋亡率高于对照组（P＜0.05）.结论 腺病毒介导HSV-TK基因转入人卵巢癌SKOV-3细胞并获稳定表达,Ad-HSV-TK/GCV自杀基因系统能明显抑制卵巢癌细胞增殖,促进卵巢癌细胞凋亡.     

HSV—TK／GCV系统对小鼠肝癌细胞旁杀伤效应的观察

目的 研究单纯疱疹病毒-胸苷激酶/9-(1,3-二羟-2-丙氧甲基)鸟嘌呤(HSV-TK/GCV)系统对小鼠肝癌细胞旁杀伤效应。方法 应用逆转录病毒载体介导HSV-TK基因修饰MM45T.Li细胞,命名为M45/TK,将M45/TK细胞或M45/TK细胞与未经基因修饰的M45细胞等比例混合接种Balb/c小鼠皮下,联合应用GCV,观察其致瘤性及其体内的旁杀伤效应。免疫组化分析肿瘤组织中免疫细胞的浸润情况。结果 M45/TK细胞在小鼠体内致瘤性显著下降(P<0.01),说明在体内GCV对M45/TK也很敏感,并且M45/TK细胞在小鼠体内具有明显旁杀伤效应,即肿瘤生长明显受到抑制(P<0.05)。M45/TK细胞联合GCV治疗组的肿瘤组织中有较多的CD4~ ,CD8~ 淋巴细胞浸润。结论 HSV-TK/GCV系统对小鼠肝癌细胞具有良好的旁杀伤细胞效应,并提示机体的免疫反应,可能参与增强自杀基因系统的旁杀伤效应。     

腺病毒介导的KDR-HSV-tk系统对血管内皮细胞的杀伤作用及旁观者效应

目的研究腺病毒介导的KDR-HSV-tk系统对血管内皮细胞的杀伤作用及旁杀效应。方法体外构建受KDR启动子和巨细胞病毒(CMV)启动子调控并可表达HSV-tk基因的Ad KDR-HSV-tk和Ad CMV-HSV-tk,经293细胞包装、扩增后,分别感染表达KDR的人脐静脉血管内皮细胞(HUVEC)和不表达KDR的人鼻咽癌细胞CNE-2,建立HUVEC/tk及CNE-2/tk,观察丙氧鸟苷(GCV)处理后HUVEC杀伤率及旁观者效应。结果受感染的HUVEC和CNE-2细胞中均有绿色荧光蛋白的表达。在感染复数(MOI)为100的条件下,GCV浓度由0增至50 mg/L时含Ad KDRHSV-tk的HUVEC和CNE-2细胞存活率从100%分别降至(23.1±3.9)%和(69.8±3.1)%(P0.01);感染Ad CMV-HSV-tk的HUVEC和CNE-2细胞存活率从100%分别降至(13.9±2.9)%和(15.7±5.2)%(P0.05);HUVEC/tk细胞对GCV的敏感性明显高于亲代HUVEC细胞,HUVEC+HUVEC/tk混合细胞的生存率随HUVEC/tk比例的增加而下降,说明Ad KDR-HSV-tk/GCV系统不但能杀伤转染tk基因的HUVEC,也能杀伤未导入转染tk基因的HUVEC细胞,存在明显的旁观者效应。结论腺病毒介导的KDR-HSV-tk/GCV系统对血管内皮细胞具有特异的杀伤作用及旁观者效应,为抗肿瘤血管靶向治疗奠定了基础。     

18β-GA对人高转移卵巢癌HO-8910PM细胞增殖、黏附和侵袭能力的影响

目的观察18β-甘草次酸（18β-GA）对人高转移卵巢癌HO-8910PM细胞增殖、黏附和侵袭能力及黏附斑激酶（FAK）、基质金属蛋白酶（MMP）-9表达的影响。方法将18β-GA作用于HO-8910PM细胞,采用MTT法检测HO-8910PM细胞增殖抑制率;细胞黏附试验检测细胞黏附能力;Transwell chamber法检测细胞侵袭能力;Westernblot法检测细胞FAK、MMP-9蛋白表达水平。结果 18β-GA明显抑制高转移卵巢癌细胞HO-8910PM的生长增殖、黏附和侵袭能力;Western blot法检测表明药物能下调FAK、MMP-9蛋白的表达。结论 18β-GA可抑制HO-8910PM细胞黏附、侵袭,其机制可能是通过下调FAK、MMP-9蛋白表达而进行的。     

大肠癌癌细胞缝隙连接蛋白Cx43表达及与肿瘤转移的相关性探讨

目的探讨癌细胞能穿出血管内皮进入靶器官继续生长形成转移瘤的机理。方法将人血管内皮细胞单独培养及分别与大肠癌低转移细胞HT29、高转移细胞Lovo共同培养,至细胞长成单层采用免疫组化SP法检测细胞缝隙连接蛋白Cx43表达。结果在单纯血管内皮细胞Cx43蛋白表达最强,次之为与HT29细胞共培养,而与Lovo细胞共培养后Cx43几乎无阳性表达。结论 Cx43蛋白在大肠癌细胞转移中起重要作用;检测Cx43蛋白表达有助于判断肿瘤的转移能力。     

TK 基因治疗库欣病的实验研究

目的：探讨胸苷激酶（ TK）基因在库欣病的基因治疗中的作用及机制。方法采用免疫印迹法检测腺病毒载体AdPOMCTK转入小鼠垂体瘤AtT20细胞及人乳腺癌T47D细胞后TK基因的表达情况;采用非放射性细胞增殖检测试剂盒检测AdPOMCTK在不同感染复数（ MOI）下转染AtT20细胞和人T47D细胞后对更昔洛韦（ GCV）的敏感性。将转染了AdPOMCTK的AtT20细胞和未经转染的细胞以不同比例混合,观察旁观者效应。结果 TK基因转染入AtT20细胞并成功表达,但在T47D细胞中表达不明显,说明POMC启动子具有靶向性;即使在低MOI下,转染组细胞仍明显表现出对GCV的敏感性;混合细胞与对照细胞相比杀伤作用明显,说明旁观者效应存在。结论将TK基因导入AtT20细胞并经GCV处理后可明显降低细胞存活率。本研究为临床TK基因治疗库欣病奠定了实验基础。     

人卵巢癌细胞HABP1的表达及其与侵袭转移能力的相关性

目的探讨透明质酸结合蛋白1（HABP1）在卵巢癌侵袭转移过程中的作用。方法分别用荧光实时定量RT—PCR和Western blot法检测HABP1 mRNA和HABP1蛋白在人卵巢癌细胞株HO-8910及高转移HO-8910PM细胞株中的表达,采用体外侵袭实验测定细胞侵袭能力。结果HO-8910PM中HABP1 mRNA和蛋白的表达水平均高于HO-8910,HO-8910PM的侵袭转移能力高于HO-8910。结论HABP1的高表达可能在人卵巢癌细胞的侵袭转移过程中发挥一定作用。     

前列腺癌细胞连接蛋白43表达和细胞间隙连接交流状况

目的　观察前列腺癌 (PCa)细胞连接蛋白 (Connexin ,Cx)表达和细胞间隙连接交流(GJIC)状况 ,探讨胸苷激酶 (TK)自杀基因治疗前列腺癌时旁观者效应不够强大的原因以及GJIC与前列腺癌发生的关系。　方法　分别采用逆转录 聚合酶链式反应 (RT PCR)、链霉亲和素免疫组化法 (SABC法 )和划痕标记染料示踪技术 (SLDT)检测前列腺癌细胞系PC 3m的连接蛋白 4 3(Cx4 3)mRNA、蛋白表达和GJIC功能状况 ,并观察Cx4 3蛋白在正常前列腺和前列腺癌组织中的表达。　结果　PC 3m有Cx4 3mRNA和蛋白表达 ,但其表达较弱 ,且Cx4 3蛋白大多异常定位于细胞浆中而非细胞膜上 ;组织切片显示前列腺癌组织Cx4 3蛋白异常定位且表达水平较正常前列腺组织明显减弱 ,与病理分级呈负相关关系 (χ2 =4 0 2 5 ,P <0 0 5 ) ,高分化和中等分化、低分化腺癌的表达率分别为5 2 9%及 7 1%。此外 ,PC 3m细胞GJIC功能低下 ,半定量为 ( )或 (- )。　结论　前列腺癌细胞GJIC功能低下 ,Cx4 3基因下调表达和蛋白异常定位均可能为导致这一现象的原因。GJIC功能缺陷可能是引起单纯疱疹病毒 胸苷激酶 /更昔洛韦系统杀伤前列腺癌细胞时旁观者效应不够强大的原因 ,亦可能是前列腺癌发生、发展中的分子事件。     

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.