砷和香烟烟气溶液联合作用对大鼠淋巴细胞凋亡的影响

目的研究亚砷酸钠和香烟烟气溶液(CSS)联合作用对Wistar大鼠淋巴细胞凋亡的影响。方法按2×2析因设计将大鼠淋巴细胞分为4组:对照组、亚砷酸钠组、CSS组、联合作用组。磷脂酰丝氨酸外翻分析法检测各组细胞凋亡情况.并检测各组细胞的Alamar Blue还原率以反映细胞生长代谢情况。结果亚砷酸钠组(1043.47±55.25)、CSS组(1186.52±48.90)和联合作用组(1650.64±89.65)凋亡细胞数明显高于对照组(861.22±42.67,P<0.05);各染毒组的细胞Alamar Blue还原率均明显低于对照组(P<0.05)。析因设计方差分析结果表明亚砷酸钠和CSS对细胞凋亡具有协同式交互作用(F=10.39,P<0.05);而二者对细胞Alamar Blue还原率的影响未见交互作用(F=0.00,P>0.05)。结论亚砷酸钠和CSS均促进大鼠淋巴细胞凋亡,并存在协同式交互作用。     

氟砷单独及联合作用对正常人淋巴细胞增殖的影响观察

目的观察氟、砷单独及联合作用对正常人淋巴细胞增殖的影响.方法采用MTT实验测定亚砷酸钠及氟化钠对正常人淋巴细胞的LC50,然后以此为依据制定试验剂量(LC50的1/100～1/10),观察低剂量氟、砷单独及联合作用对正常人淋巴细胞增殖的影响.结果人淋巴细胞在经浓度为0.1,1μmol/L的NaAsO2及浓度为50mol/L的NaF染毒后,其MTT吸光度值与对照组相比,均呈下降趋势,且有统计学意义(P均＜0.01).结论氟砷联合作用对人淋巴细胞生长表现出明显的抑制作用,但经交互作用方差分析,尚不能认为氟砷联合作用对人淋巴细胞生长的抑制有交互作用(P＞0.05),低剂量亚砷酸钠及氟化钠对人淋巴细胞均存在明显的毒作用;氟与砷之间对人淋巴细胞的生长抑制作用并没有交互作用,仅表现为简单的相加作用.     

砷与氟单独及联合染毒对SGC-7901细胞基因组DNA损伤作用的SCGE法观察

目的观察砷、氟及砷氟联合染毒对SGC-7901细胞基因组DNA的损伤作用及特点。方法砷、氟染毒剂量10μmol／L，染毒后4h应用单细胞凝胶电泳技术结合彗星图像分析系统检测DNA损伤。结果①NaAsO2组尾长和尾动量明显大于对照组，NaF组拖尾率显著高于对照组；②氟砷联合染毒组拖尾率、尾DNA含量、尾长和尾动量与对照组差异均有显著意义，但氟与砷引起的DNA损伤作用之间没有观察到交互作用。结论NaAsO2与NaF均可引起DNA损伤，但它们的损伤机理可能是不同的；氟与砷联合染毒仅表现为简单相加作用。     

单细胞凝胶电泳法检测HBV患者外周血淋巴细胞DNA损伤

目的探讨乙型肝炎病毒与DNA损伤的关系以及不同感染模式慢性乙型肝炎患者(大三阳和小三阳患者)DNA损伤情况。方法应用单细胞凝胶电泳(SCGE)技术检测对照组和不同感染模式慢性乙型肝炎患者外周血淋巴细胞DNA的损伤情况,采用彗星分析软件对实验结果进行淋巴细胞损伤率、彗星尾长(Tail Extent)、彗星尾DNA百分含量(Tail % DNA)、彗星尾惯量(Tail Inertia)、Olive尾距(Olive Tail Moment)等指标进行分析。结果经SCGE技术后得HBV感染与DNA损伤断裂关系有统计学意义(P0.05);大小三阳组间DNA损伤断裂有统计学差异(P0.05)。小三阳组经SCGE技术后所得彗星图像可见有少量彗星尾。大三阳组经SCGE技术后所得彗星图像可见有明显彗星尾。慢性乙型肝炎组外周血淋巴细胞DNA损伤与对照组比较彗星尾长、尾惯量在统计学上有显著性差异(P0.05);不同感染模式的乙型肝炎外周血淋巴细胞DNA损伤比较,尾长、尾DNA百分含量和尾惯量在统计学上有统计学差异(P0.05)。结论 HBV感染可能造成外周血淋巴细胞DNA损伤,且不同感染模式的损伤情况不同。     

砷与5-氮胞苷对人淋巴细胞DNA损伤的联合作用

为探讨砷和5－氮胞苷对人淋巴细胞DNA损伤及修复的联合作用，应用单细胞凝胶电泳（SCGE）技术比较研究了5－氮胞苷与砷同时和前后作用于人类淋巴细胞产生的联合毒性，结果显示10μmol/L5-氮胞苷和10μmol/L砷单独处理人淋巴细胞2h引起明显的DNA泳动（彗星尾），但两试剂引起的DNA泳动（彗星尾）间无显差异，5－氮胞苷前处理与砷后处理2h引起的彗星尾与其单独处理组比较非常显，砷前处理与5－氮胞苷后处理引起的彗星尾与其单独处理组比较无显性差异，但较对照组差异显，10μmol/L5-氮胞苷和10μmol/L砷分别单独处理2h引起了人淋巴细胞显的DNA损伤（链断裂），5－氮胞苷与砷在对淋巴细胞DNA的损伤上表现为单纯相加作用。5－氮胞苷前处理显增加了细胞对砷的基因毒性的敏感性，或砷后处理显增加了5－氮胞苷引起的DNA损伤，5－氮胞苷后处理2h显抑制了细胞对砷所致DNA损伤的修复。     

吡格列酮对大鼠肾小球系膜细胞氧化应激的影响

目的观察吡格列酮对大鼠肾小球系膜细胞(MCs)氧化应激的影响,探讨其肾脏保护机制。方法体外培养MCs,分为正常对照(NG)组,高糖(HG)组及不同剂量吡格列酮干预(P1、P2、P3)组。应用流式细胞仪检测细胞内活性氧簇(ROS)水平,对上清液中总超氧化物歧化酶(T-SOD)、过氧化氢酶(CAT)、丙二醛(MDA)进行检测。结果与NG组比较,HG组细胞内ROS水平增加,T-SOD、CAT活力降低,MDA含量增高(P0.01)。吡格列酮各干预组上述变化均受到抑制(P0.05),且呈剂量依赖性。结论吡格列酮可剂量依赖性地抑制高糖诱导的MCs氧化应激水平。     

氟中毒大鼠骨、肾组织自由基水平的变化

目的观察氟中毒大鼠骨、肾自由基水平与钙营养的关系。方法给大鼠饮水投氟10周。利用氟离子电极法测骨氟含量，采用电子自旋共振(ESR)方法观察了不同钙营养条件下大鼠骨自由基水平，并应用流式细胞术检测肾组织细胞内活性氧含量。结果两组饮用含氟水大鼠的骨氟含量较对照组有显著性增高；饲低钙食两组大鼠骨自由基含量较常规食对照组明显升高，而常规食加氟组大鼠骨自由基含量明显比常规食对照组低；大鼠肾组织细胞内活性氧(ROS)在投氟组较之对照组有增多趋势，而这2个投氟组大鼠的红细胞超氧化物歧化酶(SOD)活性较相应对照组偏低，细胞过氧化氢酶(cAT)的活性在低钙食投氟50nlg／L组较常规食100mgF^-／L组降低。结论氧化应激在氟中毒组织损害机制中的地位在骨与肾组织中是不同的，钙营养状况在氟中毒骨相损害中有着重要作用。     

氧化应激在七氟醚保护大鼠心肌细胞缺氧/复氧损伤中的作用

目的探讨七氟醚预处理对缺氧/复氧（H/R）引起的心肌细胞损伤的保护作用及氧化应激在其中的作用。方法将H9 c2细胞随机分为正常对照组（C组）、H/R组及七氟醚预处理组（S组）,缺氧2 h后复氧1 h,观察心肌细胞活力及细胞内活性氧,同时检测心肌细胞超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-Px）活性和丙二醛（MDA）含量。结果与C组比较,H/R组细胞存活显著减少,细胞内活性氧增多,SOD及GSH-Px活性减弱,MDA含量增多（P均〈0.05）;与H/R组比较,S组细胞存活显著增多,细胞内活性氧减少,SOD及GSH-Px活性增强,MDA含量减少（P均〈0.05）。结论七氟醚可能通过抑制心肌细胞活性氧产生、增强抗氧化酶活性以减轻心肌细胞的H/R损伤。     

丹参酮对过氧化氢致慢性乙型肝炎患者外周血淋巴细胞DNA损伤的影响

目的:观察丹参酮对过氧化氢致慢性乙型肝炎患者外周血淋巴细胞DNA损伤的影响.方法:利用快速、灵敏的检测细胞DNA损伤的单细胞凝胶电泳(SCGE)技术并结合IMI 1.0慧星分析软件,以"彗星"尾长、尾%DNA、尾惯量和尾矩来评价淋巴细胞DNA的损伤程度.结果:加入丹参酮后使过氧化氢致慢性乙肝患者外周血淋巴细胞的DNA经SCGE形成的"彗星"尾长、尾%DNA、尾惯量和尾矩值减小(P＜0.05).结论:丹参酮对过氧化氢致慢性乙型肝炎患者外周血淋巴细胞DNA损伤有一定的拮抗作用.     

电针刺激内关穴对模拟失重大鼠心脑血管氧化应激的影响

目的 探讨电针刺激内关穴对模拟失重大鼠心脑血管氧化应激水平的影响。 方法 30只雄性SD大鼠随机分为尾吊组、穴位刺激尾悬吊组和对照组,尾吊组和穴位刺激尾吊组大鼠均头低位-30°尾吊7 d,穴位刺激尾吊组大鼠需进行每天30 min的电针刺激内关穴,对照组不做任何处理。三组均在7 d后测量血清、心脏组织、脑组织、颈动脉及股动脉的超氧化物歧化酶（SOD）和丙二醛（MDA）含量。 结果 尾悬吊后大鼠血清及各血管组织中SOD含量显著低于对照组,MDA含量则显著高于对照组（P<0.05）。给予电针刺激后,穴位刺激尾悬吊组大鼠SOD和MDA含量与对照组相比无显著差异。 结论 电针刺激大鼠内关穴可减轻7 d尾悬吊模拟失重效应所产生的心脑血管氧化应激。     

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.     

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.     

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.     

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.