性激素水平对染氟大鼠生精细胞凋亡的调节作用

目的探讨性激素水平对染氟大鼠生精细胞凋亡的调节作用。方法通过腹腔注射氟化钠(NaF)溶液的方法建立大鼠氟中毒模型,采用放射免疫的方法检测血清睾酮和雌二醇水平,采用末端标记法(TUNEL)检测凋亡的生精细胞。结果①NaF10、20mg·kg-1·(2d)-1染毒28d时,睾酮水平为(10.39±0.54)、(8.34±1.29)nmol/L,较对照组降低(P<0.05或0.01);染毒38d时,睾酮水平为(9.82±0.66)、(6.33±0.68)nmol/L,较对照组降低(P<0.01)。②NaF10、20mg·kg-1·(2d)-1染毒28d时,雌二醇水平为(44.24±11.32)、(36.27±3.00)pmol/L,较对照组降低(P<0.01);染毒38d时,雌二醇水平为(42.90±9.81)、(26.02±16.14)pmol/L,较对照组降低(P<0.01)。③与对照组相比,各染氟组生精细胞凋亡率均升高(P<0.01)。④生精细胞凋亡率与血清睾酮水平呈负相关(r值为-0.901～-0.886),与血清雌二醇水平呈负相关(r值为-0.989～-0.936)。结论氟在一定剂量和作用时间内可致大鼠血清性激素水平紊乱,是导致生精细胞凋亡的重要原因之一。     

氟对大鼠睾丸生殖细胞增殖细胞核抗原表达的影响

目的了解氟对大鼠睾丸生殖细胞增殖功能的影响。方法对雄性大鼠腹腔注射NaF溶液建立氟中毒模型,观察睾丸的病理学、生殖细胞数量及生精功能的改变,免疫组化法测定睾丸生殖细胞中增殖细胞核抗原(PCNA)的表达。结果高剂量染毒组(20mg/kg)与低剂量染毒组(10mg/kg)大鼠的睾丸生殖细胞数分别为(161.00±16.16)和(268.00±12.13),低于对照组(P<0.05),其生殖细胞PCNA表达率分别为(0.60±0.81)%和(0.71±0.05)%,亦低于对照组(P<0.05);其精子数目、精子活动度比对照组显著降低(P<0.05),精子畸形率比对照组显著升高(P<0.05)。结论氟可能通过抑制PCNA的表达,从而减少生殖细胞的数量,对雄性生殖系统造成损害。     

何首乌饮对衰老大鼠生精细胞凋亡的影响

目的探讨何首乌饮对衰老大鼠睾丸生精细胞凋亡的影响。方法选用18月龄Wistar大鼠为自然衰老动物模型,以12月龄大鼠作为青年对照,采用原位末端标记法和流氏细胞术分别检测何首乌饮灌胃用药60 d和30 d的18月龄大鼠睾丸组织细胞凋亡率变化和DNA含量的变化。结果与青年对照组相比,自然衰老组睾丸细胞凋亡率明显增高,单倍体和4倍体细胞明显减少并以二倍体为主,G_1/G0期细胞明显增多(P<0.05),细胞增殖指数明显降低(P<0.05);而何首乌饮用药后与自然衰老组相比,细胞凋亡率明显降低(P<0.05);4倍体和单倍体比例明显增加(P<0.05),与青年对照组无显著性差异(P>0.05);细胞增殖指数明显升高(P<0.05),G_1/G_0期细胞明显减少(P<0.05)。结论何首乌饮可以抑制生精细胞凋亡,促进细胞增殖,达到延缓睾丸组织衰老的效果,但其具体作用机制有待研究。     

肾气丸对衰老大鼠睾丸抗氧化能力和生精细胞凋亡的影响

目的观察肾气丸对衰老大鼠睾丸抗氧化能力和生精细胞凋亡的影响。方法 Wistar大鼠分成4组,制备D-半乳糖亚急性衰老大鼠模型,分别灌胃相应剂量的肾气丸或生理盐水;6 w后,检测血清睾酮和睾丸组织超氧化物歧化酶(SOD)、丙二醛(MDA)水平及睾丸凋亡曲细精管数和凋亡细胞百分率。结果与正常组比较,模型组比较正常组,大鼠血清睾酮和睾丸组织SOD水平显著下降(P<0.01),睾丸组织MDA水平及凋亡曲细精管数和凋亡细胞百分率均显著升高(P<0.01);肾气丸可明显升高衰老模型大鼠血清睾酮和睾丸组织SOD水平(P<0.05或P<0.01),明显降低睾丸组织MDA水平及凋亡曲细精管数和凋亡细胞百分率(P<0.05,P<0.01)。结论肾气丸可通过提高衰老大鼠血清睾酮水平、增强睾丸组织抗氧化能力及降低其生精细胞的凋亡指数,发挥延缓性腺衰老的作用。     

Fas/FasL途径在氟致人神经母细胞瘤SH-SY5Y细胞凋亡中的作用

目的 探讨Fas/FasL途径在氟致人神经母细胞瘤SH-SY5Y细胞凋亡中的作用.方法 用不同剂量氟化钠[NaF,0(对照)、20、40、80 mg/L].SH-SY5Y细胞进行染毒,24 h后检测细胞存活率、凋亡率和Fas、FasL mRNA表达;选择40 mg/L NaF组,观察在Fas受体激动剂(CH11)或拮抗剂(ZB4)作用下细胞凋亡率及Fas、FasL mRNA表达水平的改变.结果 40、80 mg/L组细胞存活率[(84.63±2.57)%、(69.04±5.63)%]明显低于对照组(100.00%),组间比较差异有统计学意义(P<0.01);细胞凋亡率随染毒剂量的升高呈上升趋势.40、80 mg/L组细胞凋亡率[(8.54±1.95)%、(17.94±2.71)%]明显高于对照组[(3.32±1.33)%],组间比较差异有统计学意义(Jp<0.05);NaF能不同程度地上调Fas、FasL mRNA表达,使Fas/β-actin[40mg/L组(0.94±0.51)、80 mg/L组(0.99±0.12)]和FasL/β-actin[40 mg/L组(0.96±0.42)、80 mg/L组(0.99±0.24)]比值增加.与对照组[Fas/β-actin(0.50±0.33)、FasL/β-actin(0.58±0.23)]比较,差异均有统计学意义(P<0.05).在对细胞凋亡率和Fas、FasL mRNA表达水平的影响中,NaF与CH11之间存在协同作用(,值分别为32.89、18.46、14.69,P<0.01),NaF与ZB4之间存在拈抗作用(F值分别为5.73、24.26、10.17,P<0.05或<0.01).结论 NaF可诱导SH-SY5Y细胞凋亡,Fas/FasL途径在NaF诱导SH-SY5Y细胞凋亡中起重要作用.     

白藜芦醇对兔动脉粥样硬化斑块内细胞凋亡的拮抗作用

目的 探讨白藜芦醇对兔动脉粥样硬化斑块内细胞凋亡的作用. 方法成熟健康雄性新西兰白兔70只,适应性喂养10 d后随机分为5组:正常对照组给予普通饲料,病理对照组及白藜芦醇下预组给予高脂饲料,干预组同时每天分别给予4 mg/kg、8 rag/kg和16 mg/kg的白藜芦醇;苏木精-伊红染色观察病理组织学变化,脱氧核苷酸未端转移酶介导的脱氧三磷酸尿苷缺口末端标记法(TUNEI)榆测细胞凋亡. 结果高脂饲料喂养12周后,成功建立兔动脉粥样硬化模型.正常对照组血管内膜偶见少量的凋亡细胞,病理对照组有严重的动脉粥样硬化病理改变,粥样斑块内有大量的凋亡细胞.两组细胞凋亡指数分别为2.21±0.31和10.62±1.53(P<0.01);白藜芦醇干预均可抑制斑块内细胞的凋亡,且具有剂量依赖性.与病理对照组比较,低剂量组细胞凋亡指数为9.07±1.41(P<0.05),中、高剂量组分别为7.55±0.96和5.41±1.00(P<0.01). 结论白藜芦醇可抑制兔动脉粥样硬化斑块内的细胞凋亡.从而稳定斑块、抑制动脉粥样硬化病变进展.     

染氟小鼠成骨细胞系MC3T3-E1细胞中还原型谷胱甘肽和氧化型谷胱甘肽观察

目的 观察染氟小鼠成骨细胞系MC3T3-E1细胞中还原型谷胱甘肽(GSH)和氧化型谷胱甘肽(GSSG)的水平.方法 采用噻唑蓝(MTT)法检测不同染氟条件下[F-剂量分别为0(对照)、0.5、1.0、2.0、4.0、8.0、12.0、20.0 mg/L]MC3T3-E1细胞1、2、4、10 d的细胞活性.另外,按染氟剂量,将MC3T3-E1细胞分为0(对照)、2、8、20 mg/L组,分别染氟2、4、10 d,采用高效液相色谱—串联四极杆质谱技术检测细胞内GSH、GSSG和谷氨酰胺(Gln)水平.结果 染氟1d时2.0 mg/L组细胞活性(0.57±0.05)明显高于对照组(0.49±0.03,P＜0.01);染氟4d时8.0、12.0 mg/L组细胞活性(0.49±0.07、0.47±0.09)明显低于对照组(0.63±0.06,P＜ 0.05或＜ 0.01);染氟10d时8.0 mg/L组细胞活性(1.52±0.29)明显高于对照组(0.86±0.23),而20.0 mg/L组细胞活性(0,54±0.07)明显低于对照组(P均＜0.01).染氟2、10d时20 mg/L组细胞中GSH水平[(13.92±4.63)、(0.53±0.30) μmol/L]明显低于相应的对照组[(26.42±3.67)、(24.85±5.68)μmol/L,P均＜0.01].染氟2d时2 mg/L组、染氟4d时8 mg/L组、染氟10 d时8 mg/L组细胞内GSSG水平[(1.12±0.62)、(2.13±0.62)、(2.97±1.30)μmol/L]明显高于相应的对照组[(0.55±0.22)、(1.46±0.46)、(1.35±0.50)μmol/L,P＜ 0.05或＜ 0.01].染氟4d时2 mg/L组和染氟10d时8、20 mg/L组细胞内Gln水平[(62.80±17.41)、(122.26±19.51)、(19.38±8.11) μmol/L]明显低于相应的对照组[(83.28±14.32)、(147.15±16.95) rmol/L,P均＜0.05或＜ 0.01].结论 染氟能明显改变成骨细胞内的GSH、GSSG和Gln水平,从而影响细胞内氧化还原平衡态.     

Hoechst33342/PI双荧光活染法检测氟对体外培养大鼠肾小管上皮细胞凋亡的影响

目的研究氟对体外培养的大鼠肾小管上皮细胞凋亡的影响。方法取新生Wistar大鼠肾皮质,制备细胞悬液,传代培养。给予不同浓度的氟化钠(40、80、160μmol/L)处理培养细胞48h后,用Hoechst33342/PI双荧光活染法检测细胞凋亡情况。结果倒置显微镜下发现培养细胞出现细胞碎片明显增多。Hoechst33342/PI双荧光活染法染色检测发现坏死细胞增多。紫外光激发后,40μmol/L NaF处理组出现凋亡细胞,80μmol/L NaF处理组凋亡细胞增多,160μmol/L NaF处理组凋亡细胞明显增多。绿色光激发后,发现80μmol/L NaF处理组出现染色质凝集的晚期凋亡细胞和染色质不凝集的死亡细胞,160μmol/L NaF处理组晚期凋亡细胞较以上各组明显增多。低、中、高氟浓度组凋亡率分别为15.0%、32.4%和62.2%,即随氟浓度的提高,凋亡细胞百分比增加。结论不同浓度的氟均可诱导大鼠肾小管上皮细胞凋亡,随着氟化钠浓度的增加,凋亡细胞增多。     

慢性氟中毒大鼠脑组织氧化应激水平及学习记忆功能的变化

目的 观察慢性氟中毒大鼠脑组织及血浆氧化应激水平的改变,探讨氟中毒性神经损害发病机制中氧化应激水平与学习记忆的关系.方法 SD大鼠按体质量随机分为3组,每组8只.对照组:自由饮用自来水,自来水含氟量低于0.5 mg/L;低剂量染氟组:饮水含氟量为5 mg/L;高剂量染氟组:饮水含氟量为50ms/L.实验期为6个月.检测大鼠学习记忆功能、血浆和脑组织总抗氧化能力(T-AOC)及丙二醛(MDA)水平.结果 高剂量染氟组大鼠逃避潜伏期[(14.37±3.48)s]长于对照组[(5.84±1.87)s]和低剂量染氟组[(7.18±1.42)s],两组间比较差异有统计学意义(P<0.05);高剂量染氟组、低剂量染氟组大鼠血浆和脑组织T-AOC水平[(1.37±0.27)×103 U/L、(0.24±0.06)×103 U/g Pr,(1.20±0.14)×103 U/L、(0.41±0.10)×103 U/g Pr]低于对照组[(2.17±0.11)×103 U/L,(0.79±0.11)×103 U/g Pr],两组间比较差异有统计学意义(P<0.05);高剂量染氟组大鼠血浆和脑组织MDA水平[(3.72±0.59)mmol/L、(4.01±0.21)mmol/g Pr]显著高于对照组[(2.34±0.16)nunol/L、(2.97±0.11)mmol/g Pr]和低剂量染氟组[(2.68±0.33)mmol/L、(3.38±0.21)mmol/g Pr],两组间比较差异有统计学意义(P<0.05).结论 慢性氟中毒可使机体氧化应激水平升高,大鼠学习记忆能力减退可能与氧化应激水平的升高有关.     

大肠埃希菌感染诱导小鼠生精细胞凋亡的研究

目的探讨大肠埃希菌感染对雄性小鼠生精细胞凋亡以及对凋亡调控基因Fas/FasL的影响,进一步阐明大肠埃希菌感染致男性不育的分子机理。方法用大肠埃希菌直接注入成年雄性小鼠膀胱内模拟逆行感染的途径,感染后第7d处死小鼠,取睾丸组织分别作HE染色和用TUNEL法观察生精细胞凋亡及睾丸的病理变化;免疫组化法检测Fas/FasL在睾丸组织中的表达,同时检测精子数量、精子活动率和精子畸形率。结果大肠埃希菌感染小鼠后生精细胞的凋亡指数及Fas和FasL表达水平分别为(18.50±1.50)%、(48.10±4.19)%和(34.60±4.18)%,对照组分别为(7.40±1.69)%、(23.50±2.66)%和(19.10±4.30)%,差异均有统计学意义(P均<0.05)。感染组精子数量、精子活动率和精子畸形率分别为(6.00±1.41)×106/ml、(59.80±5.29)%和(14.78±2.03)%,对照组分别为(12.00±4.12)×106/ml、(88.90±5.37)%和(5.88±1.10)%,感染组和正常对照组比较差异均有统计学意义(P均<0.01)。感染组小鼠睾丸组织出现明显的病理变化。结论雄性小鼠感染大肠埃希菌后,可导致生精细胞凋亡增加及上调Fas和FasL蛋白的表达水平;Fas和FasL在小鼠睾丸组织的高表达诱导生精细胞的凋亡,最终使小鼠精子形成减少,活动率下降,畸形率增加。大肠埃希菌感染造成生精细胞凋亡可能是导致男性不育的原因之一。     

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.