紫草萘醌类提取物通过抑制DNA合成诱导肝癌细胞凋亡

目的 研究紫草萘醌类化合物(LE)抑制肝癌细胞生长及诱导凋亡的机制.方法 MTT法测定LE对人肝癌细胞系SMMC-7721和人胚肾细胞系HEK-293的生长抑制作用;透射电镜检查、DNA电泳和原位末端标记检测凋亡;流式细胞仪分析细胞周期.结果 LE明显抑制人肝癌细胞SMMC-7721的生长.药物孵育24～72 h,电镜检查可见凋亡的典型过程;原位末端标记显示细胞核阳性染色.药物孵育16 h后流式细胞术检查:S期细胞明显减少.药物与正常传代细胞系HEK293孵育,对细胞周期没有影响.结论 LE具有专一性抗肿瘤作用,可诱导肝癌细胞凋亡.其作用机制为首先抑制DNA合成,进而引起细胞凋亡.     

紫草萘醌组分抑制移植性肝癌新生血管的形成

目的研究紫草萘醌组分体内抗肝癌作用机制。方法建立可移植性小鼠Hep-A-22肝癌皮下接种动物模型,5-氟尿嘧啶(5-FU)腹腔注射,20 mg/kg;三组紫草萘醌组分制剂灌胃(2.5、5.0、10.0 mg/kg);阴性对照组予以相同容积的溶剂灌胃。以肿瘤称重为观察指标;采用免疫组织化学染色方法测定肿瘤微血管密度(MVD)和癌细胞血管内皮生长因子(VEGF)的表达。结果三组紫草萘醌类化合物均明显抑制可移植性肝癌原位生长;抑制Hep-A-22肿瘤细胞的VEGF表达并降低肿瘤组织的MVD。结论紫草萘醌萘醌组分对小鼠肝癌移植瘤具有增殖抑制作用,对肿瘤VEGF生成的抑制可能为其机制之一。     

千金子二萜醇对人肾癌7860细胞和小鼠肾癌renca细胞体外生长的抑制作用

目的观察中药千金子体外对人肾癌7860细胞和小鼠肾癌renca细胞的抑制作用。方法将人肾癌7860细胞和小鼠肾癌renca细胞在不同浓度含千金子二萜醇(111、333、1 000、3 000、9 000μg/ml)的培养基中培养,MTT法观察千金子二萜醇对细胞体外增殖情况的影响。结果24 h后两实验组细胞增殖速度减慢,并随浓度增加增殖速度减慢明显;3 000、9 000μg/ml浓度组有统计学差异(7860细胞:P=0.005,P=0.002;renca细胞:P=0.005,P=0.003),以9 000μg/ml浓度组作用最强,人肾癌7860细胞生长抑制率达76.03%,小鼠肾癌renca细胞生长抑制率为64.65%;与空白对照比较差异显著(P=0.002,P=0.003);两实验组细胞增殖比较没有明显差异(P0.05)。结论中药千金子体外对人肾癌7860细胞和小鼠肾癌renca细胞有明显抑制作用,使两细胞体外生长被显著抑制,证实千金子二萜醇是一种有临床应用前景的抗肿瘤中药提取物。     

榄香烯体内外抑制小鼠肝癌H_（22）细胞增殖与诱导凋亡作用的研究

[目的]研究中药莪术提取物榄香烯制剂（Elemene）对小鼠肝癌H22细胞增殖的抑制及诱导凋亡的作用。[方法]体内实验,通过建立H22小鼠肝癌实体瘤模型,观察榄香烯对荷瘤小鼠肿瘤生长的抑制作用,TdT酶介导的原位缺口末端标记法（TUNEL）检测凋亡细胞。体外进行细胞培养,采用MTT法检测榄香烯对细胞增殖的影响,Annexin V-FITC/PI双染色法检测细胞的凋亡。[结果]不同实验组对荷瘤小鼠肿瘤生长的抑制作用程度不同,5-氟脲嘧啶组抑制肿瘤生长最明显,榄香烯高剂量组较低剂量组抑瘤效果明显;MTT检测到榄香烯对H22细胞株具有抑制作用,呈剂量和作用时间的依赖性;Annexin V-FITC/PI法检测到早期凋亡细胞;TUNEL法检测到凋亡细胞。[结论]榄香烯可有效抑制小鼠肝癌H22细胞的增殖,其抑制癌细胞增殖的途径是通过诱导细胞发生凋亡而完成的。     

丁酸钠对胃癌细胞株MGC-803的增殖抑制和凋亡诱导作用机制

目的研究丁酸钠对人胃癌细胞系MGC-803的生长抑制和诱导凋亡作用，并探讨其作用机制。方法以不同浓度的丁酸钠对体外培养的人胃癌细胞系MGC-803进行处理，应用MTE法检测其对细胞生长的抑制情况；应用免疫细胞化学染色法观察其对凋亡相关基因p53表达的影响。结果不同浓度的丁酸钠均可抑制MGC-803细胞的增殖，且抑制率具有剂量和时间依赖性；突变型p53在丁酸钠作用的细胞中的表达明显低于未进行处理的细胞（P〈0．05）。结论丁酸钠可抑制体外培养的人胃癌细胞的生长，诱导癌细胞发生凋亡。     

CCK-8法检测表没食子儿茶素没食子酸酯对胰腺癌PANC-1细胞增殖的抑制作用

目的 检测表没食子儿茶素没食子酸酯(epigallocatechin-3-gallate,EGCG)对体外培养的人胰腺癌细胞系PANC-1增殖的影响.方法 缺氧条件下体外培养胰腺癌PANC-1细胞,外源性给予不同剂量的EGCG(10、20、40、60、80、100、160 μg/mL)作用细胞不同时间(12、24、48 h),CCK-8法检测不同浓度药物对胰腺癌细胞增殖的影响.结果 EGCG可显著抑制人胰腺癌细胞PANC-1的增殖,其抑制率在药物浓度和时间上呈剂量依赖性和时间依赖性关系;160 μg/mL EGCG作用48 h后,PANC-1细胞的生长抑制率高达(91.03±2.32)%.结论 EGCG对体外缺氧培养的人胰腺癌细胞系PANC-1的增殖有显著抑制作用.     

蒿甲醚在体外及荷瘤小鼠体内条件下抑制人胃癌SGC-7901细胞增殖的机制

目的:探讨蒿甲醚(artemether,ART)在体外以及荷瘤小鼠体内对于人胃癌SGC-7901细胞的杀伤作用及增殖抑制作用及具体机制.方法:采用MTT法检测不同浓度ART在体外环境下对于人胃癌细胞株SGC-7901的抑制作用,采用流式细胞术对经过不同浓度的A RT处理后的人胃癌S G C-7901细胞进行细胞周期分析,检测凋亡情况.建立人胃癌裸鼠移植瘤模型,通过计算肿瘤体积和抑瘤率探讨ART在荷瘤裸鼠体内的抗肿瘤作用.利用Western blot方法探讨ART抑制肿瘤细胞生长增殖的具体机制.结果:MTT结果显示,相比于对照组ART对该株肿瘤细胞具有显著的杀伤作用(P0.05),分析应用的A RT变化、作用时间和细胞不良反应变化关系发现,ART对于人胃癌细胞株SGC-7901杀伤作用呈现时间依赖和剂量依赖特性(P0.05);FCM检测结果表明,ART抑制癌细胞增殖的机制主要是在于阻滞细胞周期进程,使其细胞周期停滞于G0/G1期和诱导细胞凋亡;与对照组比较,中、高剂量ART组对人胃癌S G C-7901细胞裸鼠移植瘤的生长抑制效果最明显(P0.05),抑瘤率分别为34.5%和41.0%.Westernblot法检测发现A R T处理后细胞增殖细胞核抗原(proliferating cellnuclearantigen,P C N A)、B淋巴细胞瘤-2基因(B-cell lymphoma-2,Bcl-2)蛋白表达量下降,Bcl-2相关X蛋白(Bcl-2associated X protein,Bax)蛋白表达量上升(P0.05).结论:ART对人胃癌细胞株SGC-7901有较明显的细胞毒效应,且具有时间依赖性和剂量依赖性;其抑制作用与阻滞细胞周期进程和诱导细胞凋亡有关.ART对人胃癌SGC-7901细胞裸鼠移植瘤的生长具有明显的抑制作用,ART阻滞细胞周期进程和诱导细胞凋亡可能与抑制PCNA、Bcl-2蛋白表达,促进Bax蛋白表达相关.     

蟾毒灵对人肝癌细胞增殖与侵袭的影响

目的:研究蟾毒灵(bufalin,Bu)对肝癌BEL-7402细胞生长、迁移侵袭的作用.方法:体外培养人肝癌BEL-7402细胞,应用CCK-8比色法、流式细胞仪、Transwell小室迁移侵袭实验观测不同浓度和作用时间Bu对肝癌细胞增殖、迁移、侵袭的影响.结果:Bu明显抑制肝癌BEL-7402细胞生长和增殖,呈浓度-时间效应关系;0.085μg/mL Bu分别作用于肝癌BEL-7402细胞48、72 h,肝癌细胞周期阻滞于G2/S期[48 h(G2:t=-6.618,P<0.01;S:t=-5.339,P<0.01),72 h(G2:t=-14.273,P<0.01;S:t=-4.812,P<0.01)];0.085μg/mL Bu作用肝癌BEL-7402细胞72 h,显著抑制肝癌细胞迁移(t=11.717,P<0.01)和侵袭(t=5.437,P<0.01).结论:Bu能抑制肝癌细胞迁移、侵袭,并且通过阻滞肝癌细胞周期于G2/S期,抑制肝癌细胞增殖,其生长抑制作用呈时间和剂量依赖效应.     

不同血清浓度及体外培养时间对小鼠成纤维细胞L929细胞系生长曲线和细胞形态学的影响

目的 探讨不同实验条件下不同血清浓度及体外培养时间对小鼠成纤维细胞L929细胞系生长曲线和细胞形态学变化的影响.方法 采用体外细胞培养技术进行小鼠成纤维细胞L929细胞的培养,并用磺基罗丹明B(sulforhodamine B,SRB)酶标仪法(A490 nm波长)测量各孔的吸光值(OD值)并转化为小鼠成纤维细胞L929细胞系生长曲线.同时,分别采用HE染色法、吖啶橙荧光染色进行小鼠成纤维细胞L929细胞系形态学观察.结果 小鼠成纤维细胞L929细胞系分别在不同浓度的血清中培养2、4、6、8 d,其表现出不同的生长和生存情况及细胞形态学改变.将该细胞系处于相同培养时间和不同血清浓度(0%、20%、40%、60%、80%、100%)时,在20%和40%血清浓度组中,成纤维细胞的生长基本表现为OD值呈现快速增加趋势、且对细胞生长促进作用较强;而血清浓度为0%和100%时对小鼠成纤维细胞L929细胞生长表现出明显抑制作用及OD值呈逐渐减小的趋势.当该细胞系处于不同培养时间、且相同血清浓度时,除0%组OD值呈现减弱趋势,其他浓度组随时间的延长OD值呈增加趋势,在4 d之内OD值增长较快,4~6 d增长趋势减弱,6~8 d增长趋势回升,尤其是100%组.在这种实验条件下,小鼠成纤维细胞L929细胞的形态学也发生了相应改变.结论 不同血清浓度及不同培养时间等体外培养环境对小鼠成纤维细胞L929细胞系生长和生存及细胞学形态均有明显影响,提示利用血清进行体外细胞培养时应充分考虑所添加血清的浓度以及细胞培养的时间.     

自然杀伤细胞抑制肝癌肺转移

目的研究自然杀伤(natural killer,NK)细胞对肝癌的抑制作用,为临床应用提供实验依据.方法从人外周血分离培养及鉴定NK细胞.在体外,研究NK细胞抑制肝癌细胞的增殖、迁徙、转移.在体内,检测NK细胞在裸鼠肝脏存活情况.利用人肝癌组织裸鼠肝脏原位移植模型来评估NK细胞在体内对肝癌生长、转移的抑制功能.通过检测NK细胞活化受体、NKB1、穿孔素和颗粒酶的表达情况来评估白介素(interleukin,IL)-2对NK细胞免疫功能的刺激作用.结果采用密度梯度法可以获取较大量的外周血单个核细胞,且能够从中分离到高活力的NK细胞.NK细胞经IL-2激活后活力增高,成簇悬浮繁殖、扩增、生长.在体外,NK细胞可抑制肝癌细胞的增殖、迁移和侵袭.在体内,NK细胞在裸鼠肝脏可长期存活;NK细胞可明显抑制裸鼠肝癌肺转移.然而,NK细胞对肝脏肿瘤生长抑制不明显.IL-2可诱导NK细胞免疫相关分子的表达并提高其肿瘤抑制功能.结论NK细胞的免疫学功能可被IL-2活化从而抑制肝癌的转移.     

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.