骨细胞密度对骨生物力学性能的影响

目的 探讨骨细胞密度是否为衡量骨生物力学性能的指标. 方法 40只7月龄雌性SD大鼠随机分为去卵巢组(OVX)、OVX+金雀异黄酮(GEN,5 mg·kg-1·d-1)和OVX+1713雌二醇(EST,10 μg·kg-1·d-1)组及假手术组(SHAM),每组lO只.手术后15周第5腰椎(L5)椎体进行压缩试验,L6椎体先行显微CT扫描测量三维骨密度和骨微结构参数,然后进行疲劳损伤试验,最后行大块组织品红染色、塑料包埋和磨片.磨片标本用于微损伤、骨细胞密度检测. 结果 去卵巢后15周时,OVX组骨细胞密度为(1268.1±191.2)个/mm2,较SHAM组(1760.8±376.6)个/mm2及EST组(1550.9±202.2)个/mm2降低(F=3.531,P<0.05);OVX组最大应力为(84.4±16.9)N,较SHAM(110.3±25.6)N、EST(103.9±15.8)N及GEN组(110.1±4.9)N降低(F=9.561,P<0.05);OVX组骨小梁连接密度为(47.4±7.4)mm-3,较SHAM(71.8±16.0)mm-3及EST组(74.0±12.7)mm-3降低(F=7.635,P<0.05);OVX组骨矿含量为(6.5±2.2)g,较SHAM组(7.9±1.2)g降低(F=2.489,P<0.05);OVX组微破裂平均长度(58.1±6.8)μm,较SHAM(24.2±8.1)/Lm、EST(36.5±9.7)μm及GEN组(28.5±7.5)μm增加(F=3.179,P<0.05);OVX组骨小梁间隔(315.0±32.7)μm,较SHAM(222.5±21.7)μm及EST组(273.3±50.O)μm增加(F=7.007,P<0.05).骨细胞密度与最大应力(R2=0.7874,P<0.05)、骨小梁连接密度(R2=0.1153,P<0.05)、骨矿含量(R2=0.1309,P<0.05)呈正相关,与微破裂平均长度(R2=0.5738,P<0.05)、骨小梁分离度(R2=0.3964,P<0.05)负相关. 结论 骨细胞在维持骨力学性能中起重要作用,骨细胞密度可能是潜在的评价骨力学性能的重要指标.     

异丙酚对幼兔心肌缺血再灌注损伤的保护作用

目的观察异丙酚对幼兔未成熟心肌缺血再灌注损伤的影响,初步探讨其作用机制。方法24只日本大耳幼兔(雌雄不限,兔龄21～28d)随机分为缺血再灌注组(A组)、异丙酚组(B组)和对照组(C组)3组。结扎冠状动脉前降支(LAD)制作在体兔心肌缺血再灌注损伤动物模型,其中C组只穿线不结扎,B组于结扎前给予异丙酚300μg·kg-1·h-1,A、B组结扎LAD60min,再灌注120min时抽取动脉血测血清一氧化氮(NO)、丙二醛(MDA)和同型半胱氨酸(Hcy)浓度,取缺血区心肌测心肌含水量,透射电镜观察缺血区心肌超微结构。结果与C组比较,A组血清NO浓度[(246.04±11.65)μmol/L]、MDA浓度[(10.20±1.90)nmol/L]、Hcy浓度[(18.62±6.33)μmol/L]和心肌含水量[(77.26±0.42)%]均升高(P<0.05),B组血清NO浓度[(280.00±13.23)μmol/L]升高(P<0.05)。与A组比较,B组血清NO浓度[(280.00±13.23)μmol/L]升高,MDA浓度[(8.00±1.17)nmol/L]、Hcy浓度[(10.54±3.76)μmol/L]和心肌含水量[(74.16±0.28)%]下降(P<0.05)。电镜观察显示,B组心肌超微结构损伤程度轻于A组,C组心肌结构接近正常。结论异丙酚对幼兔心肌缺血再灌注损伤有保护作用,其机制与异丙酚增加心肌的NO浓度、减少MDA发挥其抗氧化作用及减轻Hcy堆积等有关。     

长春新碱对大鼠小肠肌电及动力的影响

目的 探讨抗肿瘤药长春新碱(VCR)对清醒大鼠小肠肌电和动力及相关机制的影响.方法 SD大鼠72只,分为6组,A组为对照组(n=18),尾静脉注射0.9%氯化钠溶液;B组为VCR尾静脉注射组,按给药剂量分为0.25 mg/kg(n=6)、0.5 mg/kg(n=6)和0.75 mg/kg(n=18)组;C组为假手术组(n=6),仅剖腹,尾静脉注射0.9%氯化钠溶液;D组为假手术+VCR 0.75 mg/kg(n=6);E组为双侧膈下迷走神经切断+0.9%氯化钠溶液(n=6);F组为双侧膈下迷走神经切断+VCR 0.75 mg/kg(n=6).观察用药后大鼠小肠的肌电及动力变化.采用生物机能实验系统记录小肠慢波频率、曲线下面积,移行性复合运动(MMC)周期、MMC Ⅲ相持续时间;测定小肠推进率,免疫荧光染色观察肠肌间神经元及Cajal间质细胞的表达.结果 VCR 0.25 mg/kg组对小肠动力无明显改变.0.5和0.75 mg/kg组均出现小肠肌电活动异常,且随作用时期不同表现不同,静脉注射(51.00±14.27)min后MMC模式被连续性峰电取代,(78.33±13.08)min后MMC逐渐恢复,0.5和0.75 mg/kg组MMC周期分别为(343.17±142.93)s和(302.67±66.67)s,较A组[(740.22±98.92)s]缩短(F=31.325,P<0.01).用药后第3天,0.5和0.75 mg/kg组曲线下面积为(2.56±0.30)mV·s和(2.57±0.56)mV·s,较A组降低[(4.04±0.64)mV·s,F=11.442,P<0.01].用药第3天,VCR 0.75 mg/kg组小肠推进率为(33.59±1.43)%,较A组减慢[(60.34±2.41)%,t=23.360,P<0.01].迷走神经切断组用药当日仍保持MMC相模式,第3天出现不规则峰电活动及慢波节律紊乱,VCR组曲线下面积为(2.49±0.33)mV·s,较A组降低[(4.10±0.80)mV·s,t=4.549,P=0.001].用药第3天,VCR 0.75 mg/kg组Cajal间质细胞阳性面积比为(5.84±3.11)%,较A组减少[(24.90±1.86)%,t=20.357,P<0.01];肠肌间神经元阳性面积比为(14.37±2.00)%,与A组比较差异无统计学意义[(14.17±2.63)%,P>0.05].结论 VCR改变小肠肌电活动及动力,并与剂量及时间相关.推测初期是通过迷走神经通路增强小肠运动,后期损伤Cajal间质细胞,导致小肠动力减弱.     

淫羊藿总黄酮对去卵巢大鼠骨组织细胞凋亡的影响

目的 观察淫羊藿总黄酮(HEF)对去卵巢大鼠骨组织中细胞凋亡的影响.方法 54只雌性SD大鼠随机分成6组:假手术组,去卵巢组,尼尔雌醇组(0.1 mg·kg-1·d-1)和HEF低、中、高剂量组(40,80和160 mg·kg-1·d-1),治疗12周,测定大鼠令身骨密度及雌二醇水平,采用3'-OH末端DNA原位标记技术和透射电镜检测细胞凋亡,并用免疫组化方法观察骨转化生长因子β1(TGF-β1)、成纤维细胞生长因子(FGF-2)和凋亡相关基因Fas的蛋白表达.结果 HEF增加去卵巢大鼠的全身骨密度,中、高剂量组与去卵巢组差异有统计学意义(均P<0.01),但不增加血清雌二醇水平(P>0.05).去卵巢组骨细胞、成骨细胞凋亡较假手术组明显增高(P<0.01),HEr组明显降低(P<0.01).与去卵巢组相比,HEF组Fas的表达明显降低(P<0.01),TGF-β1、FGF-2表达明显增加,尤以中、高剂量组为显著(P<0.01).结论 HEF对去卵巢大鼠骨丢失具有防治作用,其部分机制可能与促进TGF-β1、FGF-2,抑制Fas蛋白的表达和抑制骨细胞、成骨细胞凋亡有关.     

维生素A对大鼠实验性肺气肿肺泡壁细胞增殖与凋亡的影响

目的 观察维生素A对大鼠实验性肺气肿的干预作用,探讨其对肺泡壁细胞增殖和凋亡的影响.方法 雄性Wistar大鼠24只,采用随机数字表法分为对照组、模型组和维生素A组,每组8只.模型组、维生素A组在实验之初采用气管内滴入2 kU/kg弹性蛋白酶复制肺气肿模型,对照组气管内滴入等量生理盐水,术后第5周起进行药物干预,维生素A组每天给予100 kU/kg维生素A灌胃,其他两组给予等量油剂,共进行4周.实验第8周后处死大鼠.行HE染色观察各组大鼠肺泡的病理学变化,免疫组织化学法观察增殖细胞核抗原(PCNA)的表达,末端脱氧核酸转移酶介导的dUTP缺口末端标记(TUNEL)法观察肺泡壁细胞的凋亡.统计学处理采用单因素方差分析,多组间两两比较采用LSD法.结果 模型组平均肺泡数(43±11)明显低于对照组(101±15)和维生素A组(56±8);平均肺泡面积[(3763±504)μm2]明显高于对照组[(1919±270)μm2]和维生素A组[(2710±276)μm2];增殖指数[(30.7±7.6)%]明显高于对照组[(9.9±1.8)%],明显低于维生素A组[(45.4±5.0)%];凋亡指数[(22.0±4.6)%]明显高于对照组[(9.8±1.7)%]和维生素A组[(17.3±3.5)%];增殖指数/凋亡指数(1.03±0.19)与对照组(1.45±0.52)无明显差别,明显低于维生素A组(2.73±0.64).结论 维生素A能促进弹性蛋白酶诱导大鼠实验性肺气肿的肺泡壁细胞增殖并抑制其凋亡,使肺泡壁细胞增殖/凋亡的平衡向增殖倾斜,从而对大鼠实验性肺气肿起到一定的改善作用.     

硫酸羟氯喹治疗MRL/lpr狼疮鼠的疗效研究

目的 探讨硫酸羟氯喹(HCQ)对MRL/lpr狼疮鼠的疗效及作用机制.方法 MRL/lpr鼠随机分为HCQ治疗组、青蒿琥酯(ART)治疗组和对照组.18周龄时HCQ组给予HCQ 150 mg·kg-1·d-1,ART组给予ART 50 mg·kg-1·d-1治疗14周.考马斯亮蓝法检测尿蛋白定量(24 h),酶联免疫吸附法(ELISA)检测抗双链DNA(dsDNA)抗体水平,观察肾脏病理改变,流式细胞术检测脾脏和淋巴结中CD4+Foxp3+T细胞百分率.结果 ①尿蛋白定量(24 h)28周时HCQ组[(2.5±2.0)mg]和ART组[(2.4±2.0)mg]低于对照组[(4.8±3.2)mg](P<0.05),30周时HCQ组[(2.8±1.1)mgj和ART组[(2.4±1.9)mg]显著低于对照组[(6.4±1.9)mg](P<0.01).②32周龄时HCQ组体质量[(41.4±1.6)g]显著高于对照组[(37.1±1.0)g](P<0.01),血清肌酐[(7.8±4.0)μmol/L]低于对照组[(12.5±2.3)μmol/L](P<0.05),血清抗dsDNA抗体水平[(3047±1025)U/ml]显著低于对照组[(6093±2935)U/ml](P<0.05).③HCQ组和ART组肾脏病理损伤较对照组减轻.④HCQ组[(2.3±0.7)%]和ART组[(2.2±0.5)%]脾脏中CD4+ Foxp3+T细胞百分率均显著高于对照组[(1.5±0.5)%](P<0.05),HCQ组[(0.68±0.33)%]和ART组[(0.97±0.28)%]淋巴结中CD4+Foxp3+T细胞百分率均显著低于对照组[(2.15±0.72)%](P<0.01 o结论 HCQ治疗MRL/lpr狼疮有效,可以改善肾脏病理损伤,降低尿蛋白.HCQ和ART均能上调脾脏中的CD4+Foxp3+T细胞百分率.     

雷洛昔芬对骨保护蛋白基因缺失小鼠的抗骨质疏松作用

目的 利用骨保护蛋白(osteoprotegerin,OPG)基因剔除小鼠模型研究选择性雌激素受体调节剂雷洛昔芬对雌鼠和雄鼠的抗骨质疏松作用.方法 取二月龄OPG基因剔除(OPG-/-)的雌鼠和雄鼠各20只.随机分为雷洛昔芬组(3 mg·kg-1·d-1)和安慰剂组,另取野生犁雌鼠10只作为对照组,1个月后杀鼠取材.测量骨密度、骨生物力学、骨形态计量学,并进行骨组织病理学检查及破骨细胞染色,评价雷洛昔芬的疗效.结果 OPG-/-小鼠呈现明显的骨质疏松表型.雷洛昔芬组的雌鼠较安慰剂组腰椎、股骨骨密度明显增高(均P<0.05);骨生物力学结果显示腰椎和股骨最大载荷(P<0.05或P<0.01),弹性模鼍(P<0.05或P<0.01),结构韧性(均P<0.01)均增高,提示骨折风险性下降;破骨细胞染色示腰椎和股骨破骨细胞面积明显减少(均P<0.01);HE染色示骨小梁数目增加,连接性上升;骨形态计量学结果显示骨形成率降低(P<0.05).雷洛昔芬组的雄鼠与安慰剂组相比较无上述改变.结论 选择性雌激素受体调节剂雷洛昔芬在OPG基因缺失的情况下仍可改善雌鼠骨质疏松,其作用不完全依赖于OPG基因.雷洛昔芬对OPG-/-雄鼠无效.     

间歇性高血糖对胰岛β细胞功能和凋亡的影响

目的 观察间歇性高血糖和持续性高血糖对糖尿病大鼠胰岛β细胞功能和凋亡的影响.方法 雄性GK大鼠22只,随机分为持续高血糖组(HG)、波动性高血糖组(FG),11只Wistar大鼠作为正常对照组(NG).FG组每天定时腹腔注射超短效胰岛素类似物诺和锐并错时给予葡萄糖,造成1d中血糖浓度大幅度波动模型.HG和NG组给予生理盐水注射.制模6周后,进行葡萄糖耐量试验及胰岛素释放试验以评估胰岛β细胞的功能.以免疫组化染色及形态测量半定量分析胰岛素表达,TUNEL法观察胰岛细胞的凋亡并计数胰岛中β细胞凋亡率.结果 (1)FG组空腹血糖及糖负荷后15、30、60、120 min血糖均显著高于HG组(均P<0.01),FG组葡萄糖曲线下面积(AUCg)也高于HG组[(1 012.14±82.62对813.60±56.70)ng·ml~(-1)·h~(-1)·10~4,P<0.01];糖负荷后15、30、60、120 min胰岛素水平、胰岛素曲线下面积/葡萄糖曲线下面积(AUCi/AUCg)及15 min胰岛素增值/血糖增值(Δ115'/ΔG15')较HG组降低[(0.55±0.18对0.95±0.28,0.43±0.17对0.85±0.21,0.47±0.11对0.76±0.16,0.58±0.13对1.08±0.26)ng/ml;(9.56±2.53对21.36±4.16)×10~(-7);(3.95±3.45对27.02±8.62)×10~(-7),均P<0.05].(2)FG组胰岛素染色阳性面积、胰岛素染色阳性率和积分光密度均低于HG组(均P<0.05).(3)FG组β细胞凋亡率显著高于HG组[(24.17±7.25对16.55±5.11)%,P<0.01].结论 波动性高血糖可能较持续性高血糖对胰岛β细胞功能的损害更加明显,β细胞凋亡增加可能是血糖波动导致胰岛功能改变的机制之一.     

罗格列酮对OLETF大鼠胰岛β细胞凋亡水平的影响

目的探讨罗格列酮对2型糖尿病(T2DM)OLETF大鼠胰岛β细胞凋亡的影响。方法OLETF大鼠40只,随机分为罗格列酮干预组和对照组各20只,LETO大鼠10只为正常对照组。干预组从8周龄起以罗格列酮3mg·kg-1·d-1灌胃,其余两组以等量清水灌胃。定期行OGTT,分批宰杀,HE染色观察胰岛结构,TUNEL 免疫组化法检测β细胞凋亡率。结果干预组高血糖出现延迟,程度减轻,胰岛结构明显好于对照组。在32和40周龄时对照组β细胞凋亡率分别为0·28%±0·03%、0·26%±0·03%,干预组为0·18%±0·02%、0·17%±0·04%。同周龄干预组β细胞凋亡率显著低于对照组(P<0·01)。结论罗格列酮能显著降低OLETF大鼠β细胞凋亡率。     

原发性高血压患者血清抵抗素水平与颈动脉内膜中层厚度的关系

目的:探讨不同体质指数(BMI)的原发性高血压患者血清抵抗素(Res)水平的变化以及与颈动脉内膜中层厚度(IMT)的相关关系.方法:51例原发性高血压患者按BMI分为:肥胖组(BMI≥24,A组,23例)与非肥胖组(BMI<24,B组,28例),另选26例体检正常者作为对照组(C组),采用酶联免疫吸附法检测空腹血清Res水平;同时检测血脂、血压、身高、体重,计算BMI;采用彩色超声诊断仪测定IMT.结果:与C组空腹血清Res水平[(20.92±1.42)μg/L]相比,A组[(24.26±1.98)μg/L]和B组[(22.03±2.15)μg/L]明显升高,分别为P<0.01和P<0.05;A组与B组比较,Res水平差异有统计学意义(P<0.01);A组和B组Res均与收缩压(r=0.554,P<0.05;r=0.411,P<0.05)、TG(r=0.453,P<0.05;r=0.482,P<0.05)正相关,A组Res还与BMI(r=0.390,P<0.05)正相关,C组Res与收缩压(r=0.397,P<0.05)正相关.A组IMT[(1.17±0.48)mm]显著高于B组[(0.94±0.55)mm]和C组[(0.85±0.42)mm],均P<0.05;IMT与Res、年龄正相关.结论:Res与IMT、高血压、肥胖正相关,在动脉粥样硬化的发生和发展中起重要作用.     

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.