低氧诱导因子-1α减轻七氟烷处理小鼠心肌缺血再灌注损伤中的研究

目的:探究HIF-1α对于使用七氟烷后处理的小鼠减轻其心肌缺血/再灌注损伤的相关机制。方法:将8周龄小鼠随机分为四组分别进行假手术,心肌缺血/再灌注, HIF-1α稳定剂+心肌缺血/再灌注,HIF-1α抑制剂+心肌缺血/再灌注。对心肌缺血/再灌注模型采取经典的结扎冠状动脉左前降支,之后对小鼠进行七氟烷后处理。分别检测四组大鼠的心肌组织中HIF-1α,NF-κB,TLR4,SOD的蛋白表达水平以及相关mRNA水平,凋亡相关蛋白Bax,BCL2的表达水平,心肌组织MPO活性等。结果:在进行处理之前,四组小鼠的AAR/LV以及An/AAR差异无统计学意义(P0.05);经过处理后,I/R组小鼠的AAR/LV以及An/AAR均显著高于对照组(P0.001),DMOG+I/R组相比I/R组,AAR/LV以及An/AAR均发生了显著降低(P0.001),YC-1+I/R组相比I/R组,AAR/LV以及An/AAR又均发生了显著升高(P0.01);当小鼠发生心肌缺血/再灌注时,小鼠体内的HIF-1α蛋白水平显著下调,炎症因子NF-κB和TLR4显著上升,抗氧化蛋白SOD显著下降,促凋亡蛋白Bax显著升高,抗凋亡蛋白BCL2水平显著下降;而当在此基础上加入HIF-1α增强剂DMOG时,可以使炎症因子NF-κB和TLR4显著下调,抗氧化蛋白SOD显著上升,促凋亡蛋白Bax显著下降,抗凋亡蛋白BCL2水平显著升高,加入HIF-1α抑制剂YC-1现象相反;I/R组小鼠的NF-κB和TLR4水平显著升高(t=4.687,5.124,P0.05),DMOG+I/R组相比I/R组,其NF-κB和TLR4水平发生显著下降(t=4.112,4.197,P0.05),YC-1+I/R组相比I/R组,其NF-κB和TLR4水平发生显著回升(t=2.335,2.138,P0.05);经过处理之后,对照组小鼠的MPO活性为(0.28±0.54),I/R组小鼠的为(1.45±0.31),显著升高(t=3.875,P0.05),DMOG+I/R组的为(0.88±0.23),相比I/R组发生了显著降低(t=3.224,P0.05);而YC-1+I/R组的为(1.98±0.39),相比I/R组发生了显著回升(t=3.015,P0.05)。结论:HIF-1α可有效减轻大鼠在心肌损伤/再灌注所致的炎性损伤并避免心肌细胞凋亡,对心肌细胞起到良好的保护作用。     

吸入高浓度氢气对大鼠肺缺血再灌注损伤的影响

目的 探究高浓度氢气对大鼠肺缺血再灌注损伤的影响。方法 雄性SD大鼠30只,体重220～260 g,随机分为3组(n=10):假手术组(Sham组)、缺血再灌注组(I/R组)和氢气组(H2组)。采用阻断左侧肺门30min,再灌注1h的方法制备大鼠肺缺血再灌注模型。Sham组,只开胸,不建立缺血再灌注模型,I/R组和H2组建立缺血再灌注模型,H2组在再灌注期间吸入67%H2。再灌注1h后,采用ELISA法检测肺组织中白细胞介素-6(IL-6)、肿瘤坏死因子α(TNF-α)的水平,采用黄嘌呤氧化酶法和硫代巴比妥酸法检测肺组织中超氧化物歧化酶(SOD)的活性和丙二醛(MDA)的水平,并且用Western blot方法测定凋亡相关蛋白caspase-3和caspase-9的含量。结果 与Sham组比较,I/R组IL-6、TNF-α和MDA水平显著升高,SOD的活性降低,caspase-3和caspase-9的含量明显升高(P<0.05)。与I/R组比较,H2组IL-6、TNF-α和MDA水平显著降低,SOD的活性升高,caspase-3和caspase-9的含量明显降低(P<0.0...     

MMP-9在心肌缺血再灌注中的作用和机制研究

目的探讨血清基质金属蛋白酶-9(MMP-9)在心肌缺血再灌注中的表达和作用机制。方法建立大鼠急性心肌缺血再灌注模型,构建MMP-9-siRNA慢病毒,并分为对照组、缺血再灌注(I/R)组、I/R+control-siRNA组、I/R+MMP-9-siRNA组。观察并记录术后28 d各组大鼠生存情况,Western Blot检测在大鼠I/R术后1 d,7 d,14 d,28 d心肌中MMP-9的表达;M型超声评价各组大鼠心功能改变;Real time PCR法检测干扰素-γ(IFN-γ)、白介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)的变化。结果I/R+MMP-9-siRNA组大鼠生存率达80%,生存率显著提高,与I/R组比较,具有统计学意义(P0.05)。I/R组和I/R+control-siRNA组左室收缩末期内径(LVESD)、左室舒张末期内径(LVEDD)以及左心室质量指数(LVMI)增加(P0.05),对I/R组大鼠进行MMP-9-siRNA干预后,可见3个指标减少,与I/R组比较,差异具有统计学意义(P0.05)。I/R术后,MMP-9蛋白表达明显增加,与术后1 d比较,差异具有统计学意义(P0.05)。当缺血再灌注时IFN-γ、IL-6、TNF-α急剧增加(P0.05),MMP-9-siRNA干预后,可见IFN-γ、IL-6、TNF-α不同程度的减低,与I/R组大鼠比较,差异具有统计学意义(P0.05)。结论以MMP-9-siRNA作为靶标可减轻缺血再灌注损伤和心室重构,改善心室功能。     

血浆miRNA-21和miRNA-126与心肌缺血再灌注损伤的相关性研究

目的观察血浆微小核糖核酸-21(miRNA-21)、微小核糖核酸-126(miRNA-126)在急性ST段抬高型心肌梗死(STEMI)患者经皮冠状动脉介入治疗(PCI)术前后表达水平的变化,探讨二者与心肌缺血再灌注损伤的关系。方法选取2017年6月至2018年12月山西白求恩医院住院治疗的STEMI患者100例,根据冠状动脉造影梗死相关血管心肌梗死溶栓治疗试验血流分级情况分为血管自发再通(SR)组(39例)和非SR组(61例),收集患者临床资料,比较两组患者PCI术前、术后心肌肌钙蛋白I(cTnI)、肌酸激酶同工酶(CK-MB)、高敏C反应蛋白(hs-CRP)、miRNA-21及miRNA-126的表达水平,分析miRNA-21、miRNA-126与cTnI、CK-MB及hs-CRP的相关性。结果两组患者一般临床资料比较,差异均无统计学意义(均P>0.05)。两组患者PCI术前cTnI、CK-MB及hs-CRP表达水平比较,差异均无统计学意义(均P>0.05);非SR组术后cTnI[(58.43±39.11)ng/ml比(39.66±21.19)ng/ml]、CK-MB[(138.94±69.77)ng/ml比(92.78±37.01)ng/ml]、hs-CRP[(21.33±10.74)mg/L比(16.50±7.64)mg/L]表达水平较SR组更高,差异均有统计学意义(均P<0.05)。两组患者PCI术前miRNA-21和miRNA-126的表达水平比较,差异均无统计学意义(均P>0.05);非SR组患者PCI术后miRNA-21[(1.98±0.46)比(1.68±0.22),P<0.001]、miRNA-126[(2.54±0.56)比(1.63±0.22),P<0.001]表达水平较SR组更高,差异均有统计学意义。Pearson相关性分析显示,miRNA-21表达水平与cTnI(r=0.557,P<0.001)、CK-MB(r=0.625,P<0.001)、hs-CRP(r=0.606,P=0.001)呈正相关,miRNA-126表达水平与cTnI(r=0.543,P=0.004)、CK-MB(r=0.669,P<0.001)、hs-CRP(r=0.558,P=0.002)均呈正相关。结论再灌注损伤时miRNA-21和miRNA-126的表达水平上调,二者与心肌损伤程度呈正相关。     

西维来司钠对大鼠脑缺血再灌注损伤的保护作用

目的 探讨西维来司钠(ONO-5046)对大鼠全脑缺血再灌注(I/R)损伤的保护作用及其机制.方法 SD大鼠随机分为假手术组、I/R组和I/R+ONO-5046组,I/R组和I/R+ONO-5046组根据再灌注时间的不同分为6、12、24、48 h四个亚组.采用四血管阻断法制备I/R模型,缺血15 min,I/R+ONO-5046组于再灌注时经股静脉持续给予 ONO-5046 2 mg·kg-1·h-1,假手术组和I/R组给予生理盐水.观察大鼠脑组织病理学变化,并检测中性粒细胞弹性蛋白酶(NE)、丙二醛 (MDA)含量及超氧化物歧化酶(SOD)、肿瘤坏死因子-α(TNF-α)活性.结果 I/R后,NE含量随再灌注时间延长而不断增强(P＜0.05或P＜0.01),TNF-α表达量也增加并于再灌注12 h达最高峰(P＜0.01).ONO-5046组显著降低缺血再灌注后脑组织NE、MDA含量,升高SOD活性以及减少TNF-α表达,明显改善脑组织病理形态.结论 ONO-5046对脑缺血-再灌注损伤有明显的保护作用,其机制可能与降低NE、MDA含量,升高SOD活性及下调TNF-α阳性表达细胞有关.     

低剂量三羟异黄酮对家兔缺血/再灌注损伤心肌梗死范围的影响

目的研究三羟异黄酮(genistein,GST)对家兔心肌缺血/再灌注(I/R)损伤心肌梗死范围的影响。方法通过阻断家兔心脏左冠状动脉前降支45min,再灌注180min引起心肌I/R损伤,测量血流动力学数据及心肌梗死面积,梗死面积(IS)用IS与缺血面积(AAR)的比值表示。结果在心肌I/R期间,平均动脉压(MAP),率压积(RPP)和左心室±dp/dtmax显著降低;损伤对照组的IS/AAR为(61.3±4.5)%,缺血后灌注GST(0.5,1.0,和2.0mg/kg)分别使IS/AAR为(45.5±4.3)%,(42.6±5.1)%(P<0.01)和(57.8±6.2)%(P>0.05)。缺血前灌注GST(0.5mg/kg)使IS/AAR为(35.8±4.4)%(P<0.01)。以上各剂量GST对缺血面积(AAR)没有影响。结论缺血前和缺血后灌注低剂量(≤1.0mg/kg)GST可减少家兔心肌缺血/再灌注损伤模型的心肌梗死面积。     

缺血后适应对心肌缺血再灌注损伤大鼠p38丝裂原活化蛋白激酶和血小板-白细胞聚集体表达的影响

目的:从炎症-血栓机制角度初步探讨缺血后适应减轻心肌缺血再灌注损伤的可能机制。方法:60只SD大鼠随机分为六组:假手术组(n=10)、缺血再灌注(I/R)组(n=10)、缺血后适应组(n=10)、SB203580组(n=10)、Anisomycin+缺血后适应(Ani+缺血后适应)组(n=10)和Ani组(n=10)。建立大鼠心肌缺血再灌注模型,检测心肌损伤标志物血清肌酸激酶同工酶(CK-MB)和肌钙蛋白I(Tn I)水平,采用流式细胞仪在不同时间点检测血小板-白细胞聚集体(PLA)表达水平,使用2,3,5-氯化三苯基四氮唑(TTC)染色检测心肌梗死面积以及利用免疫蛋白印迹法测定磷酸化p38丝裂原活化蛋白激酶(p38MAPK)表达水平。结果:与I/R组相比,缺血后适应组和SB203580组的CK-MB和Tn I水平、梗死面积和再灌注60 min和3 h时PLA表达水平明显降低(P0.05)。与缺血后适应组相比,SB203580组、Ani+缺血后适应组和Ani组的上述指标明显升高(P0.05),Ani组和I/R组之间没有差异(P0.05)。与I/R组相比,缺血后适应组、SB203580组和Ani+缺血后适应组明显抑制了磷酸化p38MAPK的表达(P0.05),Ani组的磷酸化p38MAPK表达水平明显升高(P0.05)。与缺血后适应组相比,Ani+缺血后适应组和Ani组磷酸化p38MAPK表达水平明显升高(P0.05)。SB203580组具有与缺血后适应组类似的心脏保护作用。在Tn I、CK-MB、梗死面积和PLA水平方面,Ani+缺血后适应的保护作用减弱。结论:缺血后适应通过抑制p38MAPK的磷酸化而减少再灌注过程中PLA的表达,从而减轻缺血再灌注损伤。     

缺血后处理对梗阻性黄疸肾缺血再灌注损伤大鼠血清 TNF-α水平的影响

目的探讨缺血后处理对梗阻性黄疸肾缺血再灌注损伤大鼠血清TNF-α水平的影响。方法 60只SD大鼠随机分成梗阻性黄疸对照组(S组)、梗阻性黄疸肾缺血再灌注组(I/R组)、梗阻性黄疸肾缺血再灌注缺血后处理组(IPO组),每组20只。根据缺血后再灌注时间点各组又分为再灌注0 h(T0)、1 h(T1)、3 h(T2)、6 h(T3)4个亚组各5例。检测再灌注后的各时点血清中尿素氮(BUN)、肌酐(Cr)、TNF-α水平,观察肾组织的病理改变。结果 I/R组和IPO组血清BUN、Cr、TNF-α水平均高于S组(P均<0.05),IPO组T2时间点血清Cr、BUN、TNF-α水平均低于I/R组(P均<0.05)。结论缺血后处理可以下调大鼠血清TNF-α水平,从而减轻梗阻性黄疸大鼠肾缺血再灌注损伤,其机制可能与抑制炎症反应有关。     

炎症因子对心肌间质的影响及缺血后处理对其保护作用

目的探讨缺血后处理对大鼠心脏缺血-再灌注损伤中肿瘤坏死因子(TNF)-α和白细胞介素(IL)-6的影响,及其对心肌间质和心脏功能的保护作用。方法将24只雄性SD大鼠随机分为三组,假手术对照组(SC组,n=8)、缺血-再灌注组(I/R组,n=8)和缺血后处理组(IPTC组,n=8),结扎左冠状动脉前降支造成缺血-再灌注损伤动物模型。通过心室内插管、多导生理记录仪监测左室血流动力学变化,计算心肌组织中胶原含量变化,酶联免疫吸附试验(ELISA)试剂盒检测血浆中TNF-α和IL-6浓度改变,Western印迹检测基质金属蛋白酶(MMP)-2表达情况。结果与SC组比较I/R组血浆TNF-α和IL-6浓度升高,同时心肌MMP-2蛋白明显升高,而心肌胶原含量下降并伴随左室心功能下降;IPTC组在血浆TNF-α和IL-6浓度明显降低的同时,心肌MMP-2蛋白也明显降低,而心肌胶原含量、左室舒缩功能明显高于I/R组。结论 IPTC对缺血-再灌注损伤心肌有保护作用,机制可能与其减少炎性介质TNF-α和IL-6的释放以抑制MMP-2的表达,从而减轻心肌间质的损伤有关。     

粉防己碱抑制心肌细胞磷酸化减轻缺血/再灌注损伤引发的炎症反应

目的:探讨心肌缺血/再灌注过程中粉防己碱(Tet)对核转录因子(NF)-κB的抑制因子(IκB-α)磷酸化及肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)表达的影响以及机制。方法:60只SD大鼠被随机分为3组:缺血/再灌注损伤组(I/R)、假手术组、粉防己碱治疗组(Tet)。I/R组结扎大鼠左前降支造成心肌缺血30min后再灌注24h,然后处死大鼠;假手术组只穿针不结扎,余步骤同I/R组;Tet组在缺血前20min腹腔注射Tet,余步骤同I/R组。处死大鼠24h后取心肌标本,用酶联免疫吸附法(ELISA)检测心肌组织中TNF-α、IL-6表达水平,应用免疫组织化学方法检测磷酸化IκB-α(P-IκB-α)的表达。结果:Tet组与I/R组相比TNF-α、IL-6表达水平明显减低[(208.40±25.12)pg/ml∶(306.65±17.78)pg/ml,(587.40±137.40)pg/ml∶(1003.75±138.33)pg/ml,P均0.01],而Tet组与假手术组相比表达明显增强[(208.40±25.12)pg/ml∶(61.45±9.20)pg/ml,(587.40±137.40)pg/ml∶(229.25±90.13)pg/ml,P均0.01]。Tet组大鼠心肌细胞胞浆中P-IκB-α的表达明显低于I/R组[(0.0817±0.09)pg/ml∶(0.1755±0.01)pg/ml,但明显高于假手术组[(0.0817±0.09)pg/ml∶(0.0513±0.03)pg/ml,P均0.01]。结论:Tet可以抑制IκB-α磷酸化,显著减少前炎症因子TNF-α、IL-6的产生,减轻心肌缺血/再灌注损伤。     

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.