多种实验动物对藐小棘隙吸虫易感性的实验研究

为观察不同实验动物对藐小棘隙吸虫的易感性 ,以定量囊蚴感染幼犬 2只、幼猫 2只、新西兰兔 3只、昆明小鼠 10只、猪 2头、鸡鸭各 10只 ,并观察犬体内藐小棘隙吸虫成虫寿命、日产虫卵量以及排卵动态。结果所有感染犬、兔、猫均检获成虫 ,10只小鼠有 7只感染成功 ,其他实验动物均为阴性 ;犬、兔、猫和鼠的获虫率分别为 5 6 .15 %、5 1.45 %、2 9.82 %和 11.93%。实验犬和兔的获虫率、所获虫体大小以及虫体子宫含卵数均明显高于或大于实验猫和小鼠。上述结果表明 ,犬和兔是藐小棘隙吸虫适宜终宿主 (其中兔为终宿主新记录 ) ,猫次之 ,小鼠的易感性较低。实验犬感染藐小棘隙吸虫后第 13d开始从粪便中排卵 ,此后排卵量迅速增加 ,感染后 3个月达到高峰 ,感染后 6个月时明显下降 ,10个月时排卵量处于很低水平 ,此后 10个月仍维持同一水平 ,未见明显升降或停止排卵现象。犬体内 13～ 2 5日龄藐小棘隙吸虫成虫日产卵量为 ( 48± 2 7)个。成虫在犬体内的寿命超过 2 0个月。另外 ,3只兔感染日本血吸虫 ( 2 0 0 0尾蚴 /只 ) 2 8d后再用藐小棘隙吸虫囊蚴攻击感染 ,结果对藐小棘隙吸虫产生了明显的抗性 ,与无血吸虫感染的实验兔相比其减虫率达到 86 .78%～ 10 0 % (平均为 92 .0 9% )。藐小棘隙吸虫 /兔模型对于研究异     

多种实验动物对藐小棘隙吸虫易感性的实验研究

为观察不同实验动物对藐小棘隙吸虫的易感性，以定量囊蚴感染幼犬２只、幼猫２只、新西兰兔３只、昆明小鼠１０只、猪２头、鸡鸭各１０只，并观察犬体内藐小棘隙吸虫成虫寿命、日产虫卵量以及排卵动态。结果所有感染犬、兔、猫均检获成虫，１０只小鼠有７只感染成功，其他实验动物均为阴性；犬、兔、猫和鼠的获虫率分别为５６．１５％、５１．４５％、２９．８２％和１１．９３％。实验犬和兔和获虫率、所获虫体大小以及虫体子宫含卵     

藐小棘隙吸虫尾蚴直接感染终宿主的研究

本实验为藐小棘隙吸虫尾蚴直接经口感染终宿主人、犬的可行性研究。9只幼犬分别喂以不同数量的尾蚴(4500～88000),并于感染后3.5h～34d分别解剖。结果:实验犬藐小棘隙吸虫感染率为100％,获虫率4.01％;感染后3.5b,部分尾蚴在胃中发育成囊蚴;8b,脱囊蚴虫在小肠内发现;13d,蚴虫发育成熟,虫卵在大便中检获。两自愿者分别感染尾蚴8400条和1500条,于感染后第15d、16d自粪中检获虫卵。提示人、畜生饮含有藐小棘隙吸虫尾蚴的水可致感染。     

藐小棘隙吸虫尾蚴直接感染终宿主的实验研究

本实验为用藐小棘隙吸虫尾蚴直接经口感染终宿主人、犬的研究。９只幼犬分别喂以不同数量的尾蚴（４５００～８８０００条），于感染后３．５ｈ至３４ｄ分别解剖。结果实验犬藐小棘隙吸虫感染率为１００％，获虫率４．０１％；感染后３．５ｈ，部分尾蚴在胃中发育成囊蚴；８ｈ脱囊幼虫在小肠内发现；１３ｄ，幼虫发育成熟，虫卵在大便中被检获，两名志愿者分别口服尾蚴８４００条和１５００条，于感染后第１５ｄ、１６ｄ自粪中检获虫卵。结果提示人、畜生饮含有藐小棘隙吸虫尾蚴的水可致感染。     

藐小棘隙吸虫不经中间宿主完成囊蚴期发育的发现

本文观察了藐小棘隙虫尾蚴在天然及实验室条件下生长发育情况。结果显示该尾蚴不仅可在第二中间宿主淡水鱼的鱼鳃中发育成囊蚴,还能在英终宿主犬的胃液中以及生理盐水等实验条件下完成囊蚴期发育。这一发现解释了藐小棘隙吸虫尾蚴经口直接感染终宿主(人、犬、猫)的原因。     

福建棘隙吸虫与相关虫种随机引物扩增多态DNA分析及感染实验观察

目的：探讨福建棘隙吸虫与相关虫种分类问题。方法：应用 ２８ 个随机引物扩增多态性 Ｄ Ｎ Ａ,根据福建棘隙吸虫、藐小棘隙吸虫（安徽）与日本棘隙吸虫（福建和江西）作相似性分析;现场采检叶形棘隙吸虫（湖北）、藐小棘隙吸虫（安徽）和福建棘隙吸虫囊蚴进行人工感染实验及形态观察。结果：分析福建、安徽与江西省 ３ 种棘隙吸虫的 ４６９ 个多态 Ｄ Ｎ Ａ 片段,福建棘隙吸虫与日本棘隙吸虫福建株、日本棘隙吸虫江西株与福建株、福建棘隙吸虫与安徽的藐小棘隙吸虫间基因组 Ｄ Ｎ Ａ 的 Ｒ Ａ Ｐ Ｄ 相似率分别为 ２０．８％ 、９９．７％ 及 ９７．６％ 。湖北、安徽和福建 ３ 省均分别获得叶形棘隙吸虫、福建棘隙吸虫及日本棘隙吸虫 ３ 种棘隙吸虫。结论：福建棘隙吸虫与日本棘隙吸虫为两个独立虫种,安徽的藐小棘隙吸虫与福建棘隙吸虫为同一虫种。湖北、安徽与福建 ３ 省均存在叶形棘隙吸虫、福建棘隙吸虫和日本棘隙吸虫 ３ 种吸虫的混合感染,其中福建棘隙吸虫较为常见     

卫氏并殖吸虫和斯氏狸殖吸虫感染禽、蛙及宿主转换的研究

目的 :探讨卫氏并殖吸虫和斯氏狸殖吸虫在禽、蛙体内的分布与发育 ,以及童虫对终宿主的侵袭力。方法 :从江西、广东两省并殖吸虫流行区采集溪蟹 ,分离囊蚴。以每只动物 30 -2 0 0个囊蚴分别感染雏鸡、雏鸭、鹌鹑、鹦鹉和蛙 ,定期剖检。将禽、蛙体内所获童虫经口感染犬或猫 ,60 d后剖检 ,观察虫体发育情况。结果 :两种并殖吸虫均可在鸡、鸭、鹌鹑和鹦鹉体内存活 ,虫体分布于体腔、肝脏、肺和肌肉。所有虫体为小型滞育童虫。斯氏狸殖吸虫对蛙的感染率为 1.7%- 4 0 .0 % ,未查见卫氏并殖吸虫感染蛙。童虫经宿主转换后 ,在犬、猫胸腔或肺虫囊内检获虫体 ,除部分为成熟前期虫体外 ,多数为含卵成虫。结论 :在流行区 ,禽和蛙在人体并殖吸虫病传播中的作用 ,应予重视。     

安徽和县陈桥洲人体藐小棘隙吸虫流行区的发现

藐小棘隙吸虫(Echinochasmus liliputanus),主要寄生于犬、猫、鼠等哺乳动物和鸟类。到目前为止,国内外未见人体感染的报道。1991年春我们在安徽和县陈桥洲作居民肠道寄生虫病粪便普查时,查见大量棘口科吸虫卵,经药物驱虫,虫体和虫卵送安徽医科大学刘昌威、杨兆莘教授和福建师范大学汪溥钦教授鉴定为藐小棘隙吸虫及其虫卵。现将流行情况报告如下。     

藐小棘隙吸虫病感染方式的研究

经流行病学调查及实验研究表明，居民感染藐小棘隙吸虫系由于生饮含有该吸虫见蚴的水或食入其活囊蚴。经常喝生水的居民的感染率为20.1％，较不喝生水居民的感染率1．5％高12．6倍。该地水体中仅检到该吸虫尾蚴．未发现囊蚴。因此可以认为，藐小棘隙吸虫感染人体的主要方式是尾蚴直接经口，而囊蚴经口感染为次要。     

藐小棘隙吸虫体被超微结构的扫描电镜观察

目的 :观察藐小棘隙吸虫体被的超微形态学特征。方法 :采用扫描电镜观察实验犬体内藐小棘隙吸虫成虫的体表结构。结果 :该吸虫体被除头冠、腹吸盘和虫体亚末端外 ,均具有体棘 ,其以螺旋式规律排列成行 ,其间距由前向后逐渐增宽 ,但体棘大小基本不变。感觉乳突有 3种 ,其一是带触毛的扣状乳突 ;另两种不具触毛 ,为无触毛扣状乳突和丘状乳突 ,前者数量最多 ,分布最广。虫体表面不平坦 ,呈一定规律的凹凸状,不同部位具不同的体表结构。结论 :该虫体被超微结构是长期适应肠道内寄生而逐渐进化的结果 ,与肠道内寄生生活相适应 ,其特征在分类学上有一定意义。     

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.