用聚合酶链反应检测血清标本诊断阿米巴肝脓肿的价值

用聚合酶链反应（ＰＣＲ）检测阿米巴肝脓肿患者血清标本中的溶组织内阿米巴３００００蛋白基因,结果４２例患者中有３５例呈阳性反应,阳性率８３．３％,低于脓标本ＰＣＲ阳性率（１００％）（Ｐ〈０．０１）。３例细菌性肝脓肿、１例肝癌及１０例其它部位脓肿患者的血清和脓对照标本ＰＣＲ均呈阴性反应。对ＰＣＲ检测血标本诊断阿米巴肝脓肿的价值进行了讨论。     

应用ELISA检测阿米巴脓抗原和循环抗原诊断阿米巴肝脓 …

应用ＥＬＩＳＡ法检测阿米巴肝脓肿患者脓液和血清标本中的阿米巴抗原,结果４２例患者中有４１例检出脓抗原检出率为９７．６％,其中包括８例镜检阿米巴滋养体阳性和３３例镜检阴性者;有３９例检出循环抗原,检出率为９２．９％,脓抗原阳性反应强度高于循环抗原者（Ｐ〈０．０５）,各种对照标本的阿米巴抗原检出的率为０,提示可用ＥＬＩＳＡ抗原检测法替代镜检和培养法进行阿米巴肝脓肿的病原学诊断。     

阿米巴肝脓肿患者血清sIL－2R水平与红细胞免疫功能相关性的研究

本文检测了３２例阿米巴肝脓肿患者的血清可溶性白细胞介素２受体（ｓＩＬ─２Ｒ）水平及红细胞免疫功能,并分析ｓＩＬ─２Ｒ与红细胞免疫功能之间的相关性。结果显示,阿米巴肝脓肿患者的ｓＩＬ─２Ｒ水平显著地高于正常对照组,而红细胞免疫功能则显著地低于正常对照组。经流式细胞仪测定,患者ＣＤ４细胞减少、ＣＤ８细胞增高,ＣＤ４／ＣＤ８比值下降。相关分析表明,血清ｓＩＬ─２Ｒ水平与红细胞Ｃ３ｂ受体花环率（ＲＢＣ─Ｃ３ｂＲＲ）呈显性负相关。阿米巴肝脓肿患者血清ｓＩＬ─２Ｒ水平的升高可能是导致患者红细胞免疫功能低下原因之一。     

替硝唑治疗阿米巴肝脓肿的疗效观察

目的观察替硝唑对阿米巴肝脓肿的临床疗效。方法以每日顿服替硝唑２．０ｇ，５日疗法治疗３３例阿米巴肝脓肿患者，并与甲硝唑１４日疗法治疗３１例阿米巴肝脓肿患者进行比较。结果替硝唑组患者体温恢复正常时间（３．７±０．５天），平均住院天数（２４．３±１．５天）及总有效率（７８．８％）与甲硝唑组比较，差异无显著性（Ｐ＞０．０５）。但替硝唑组患者脓腔缩小所需时间较短，肝区疼痛消失较早，不良反应亦比甲硝唑组较少（Ｐ＜０．０５）。结论替硝唑是一种治疗阿米巴肝脓肿的新的良好药物     

用聚合酶链反应检测肝脓液中溶组织内阿米巴复制基因片段

试用聚合酶链反应（ＰＣＲ）检测肝脓液中有无溶组织内阿米巴致病株编码３００００蛋白的复制基因的存在，结果２３例阿米巴肝脓肿患者的ＰＣＲ反应均呈阳性，而３例细菌性肝脓肿、１例肝癌及１０例其他部位脓肿患者的对照标本呈ＰＣＲ阴性反应，提示ＰＣＲ可用于阿米巴肝脓肿的病原学诊断。     

应用ELISA检测阿米巴脓抗原和循环抗原诊断阿米巴肝脓肿的价值

应用ELISA法检测阿米巴肝脏肿患者脓液和血清标本中的阿米巴抗原。结果42例患者中有41例植出脓抗原,检出率为97．6％,其中包括8例镜检阿米巴滋养体阳性和33例镜检阴性者;有39例检出循环抗原,检出率为92．9％。脓抗原阳性反应强度高于循环抗原者（P＜0．05）。各种对照标本的阿米巴抗原植出率为0。提示可用ELISA抗原检测法替代镜检和培养法进行阿米巴肝脓肿的病原学诊断。     

人肝细胞癌和癌旁组织中性激素受体的改变

目的探讨肝细胞癌（ＨＣＣ）患者癌组织与癌旁组织中雄、雌激素受体的变化．方法用葡聚糖包裹活性炭吸附法检测２１例ＨＣＣ患者的癌组织和癌旁组织中雄激素受体（ＡＲ）和雌激素受体（ＥＲ），同时测量７例男性肝硬变患者肝组织中的ＡＲ和ＥＲ．结果癌组织中ＡＲ阳性率（７１４％）显著高于癌旁组织（３１３％）（Ｐ＜００１）及硬变肝组织（Ｐ＜００５）中的ＡＲ阳性率（２８６％），而ＥＲ含量均无显著差异（Ｐ＞００５）．结论ＡＲ表达的增加与肝细胞的癌变有关，部分ＨＣＣ具有雄激素依赖性，为ＨＣＣ可能的内分泌治疗提供分子生物学方面的理论依据．     

原发性肝癌患者外周血中甲胎蛋白mRNA的意义

目的由于ＰＣＲ技术的应用,血循环中癌细胞的检测近有很大进展．本文用ＲＴＰＣＲ检测肝癌（ＨＣＣ）和其他慢性肝病患者外周血中ＡＦＰｍＲＮＡ,藉以反映ＨＣＣ细胞的存在,并与其他血清标记物比较．方法ＨＣＣ患者２２例,肝硬变和慢性乙型肝炎患者各１０例,健康成人受试者（对照）５例．取患者和对照的外周血,分离单核细胞,提取总ＲＮＡ并作电泳鉴定,用合成的两对引物进行巢式ＲＴＰＣＲ扩增ＡＦＰｍＲＮＡ,同时分析血清ＡＦＰ和乙肝标记物．结果ＡＦＰｍＲＮＡ在１３例ＨＣＣ（５９１％）,２例肝硬变（２００％）患者外周血中测到,其余标本均为阴性．ＡＦＰｍＲＮＡ阳性的１３例患者肿瘤均大于５ｃｍ,为晚期患者．在该１３例患者中仅有６例（４６１％）在血清中测到ＡＦＰ,但有１２例（９２３％）ＨＢｓＡｇ,抗ＨＢｅ,抗ＨＢｃ全阳性,而ＡＦＰｍＲＮＡ阴性的５例该３标记物全阴性．结论ＲＴＰＣＲ扩增ＡＦＰｍＲＮＡ是检测ＨＣＣ和肝硬变患者循环肝癌细胞的敏感方法．患者外周血中的ＡＦＰｍＲＮＡ有可能作为肿瘤转移和复发的标记对ＨＣＣ诊断、随访观察和疗效评定有较大临床意义．     

不同外周血标本中HCV RNA检出比较

对５４例抗－ＨＣＶ阳性患者，用多聚酶链反应（ＰＣＲ）技术检测其外周血不同检材（血清、血浆、外周血单核细胞）中ＨＣＶ ＲＮＡ，结果检出率分别为５９．３％、５０％、５５．６％，以血清标本检出率最高。外周血单核细胞（ＰＢＭＣ）中亦有较高的检出率，且在部分（６％）血清测不到ＨＣＮ ＲＮＡ时，ＰＢＭＣ中可测及，提示ＰＢＭＣ可贮存ＨＣＶ ＲＮＡ。     

转化生长因子-β1在肝细胞性肝癌中表达增强

目的转化生长因子－β１（ＴＧＦβ１）在细胞生长的负性调节上有重要作用,是肝细胞生长和增殖的强抑制物但肝癌（ＨＣＣ）患者肝组织中ＴＧＦβ１ｍＲＮＡ表达高．现检测ＨＣＣ患者外周血中ＴＧＦβ１ｍＲＮＡ表达,血清ＴＧＦβ１水平,以及肝组织中ＴＧＦβⅡ型受体（ＴＧＦβＲⅡ）的表达．方法ＨＣＣ患者外周血分离单个核细胞（ＰＢＭＣ）,提取总ＲＮＡ,用反转录聚合酶链反应（ＲＴＰＣＲ）技术扩增ＴＧＦβ１ｍＲＮＡ．血清ＴＧＦβ１水平测定用Ｐｒｏｍｅｇａ公司产的试剂盒．肝组织ＴＧＦβＲⅡ表达的分析用原位杂交法．结果ＨＣＣ患者２０例ＰＢＭＣＴＧＦβ１ｍＲＮＡ用ＲＴＰＣＲ检测阳性率达７０％,对照组阴性．ＨＣＣ患者４０例血清ＴＧＦβ１水平（２７５８ｍｇ／Ｌ±８１０ｍｇ／Ｌ）明显高于对照组（８２７ｍｇ／Ｌ±３７２ｍｇ／Ｌ）．原位杂交表明,ＴＧＦβＲⅡ在ＨＣＣ细胞的胞质中有弱表达．结论ＨＣＣ患者ＴＧＦβ１基因在转录水平和翻译水平上均显示表达增强．ＰＢＭＣ有可能代替肝组织用以检测ＴＧＦβ１ｍＲＮＡ的表达应用于基础与临床的研究．     

Detection of Entamoeba histolytica using polymerase chain reaction in pus samples from amebic liver abscess.

BACKGROUND AND OBJECTIVE: Direct demonstration of Entamoeba histolytica by conventional microscopy and in vitro culture in pus obtained from amebic liver abscess (ALA) is often unsuccessful. We evaluated polymerase chain reaction (PCR) for detection of E. histolytica DNA in such pus. METHODS: Species-specific primers were used for the amplification of E. histolytica DNA from liver pus obtained from 30 patients with ALA. Patients with pyogenic liver abscess and sterile (autoclaved) pus spiked with Entamoeba dispar and bacteria (Escherichia coli, Klebsiella spp. and Bacteroides spp.) were used as negative controls. RESULTS: PCR was positive in 83% of pus specimens from patients with ALA, and was negative in all 25 pus specimens obtained from pyogenic abscess and autoclaved pus spiked with known bacteria. Sensitivity and specificity of PCR were 83% and 100%, respectively. The overall positivity of PCR was higher compared to serological tests. CONCLUSION: PCR may be a more reliable and better alternative diagnostic modality for ALA.     

Antigenic stability and immunodominance of the Gal/GalNAc adherence lectin of Entamoeba histolytica

Immunoprecipitation of Entamoeba histolytica proteins was performed with the sera of patients recovered from amebic liver abscess and colitis. The patients' amebic infection had been acquired in diverse areas of the world. The amebic galactose and N-acetyl-D-galactosamine-inhibitable adherence lectin was the major amebic antigen immunoprecipitated. The adherence lectin was recognized by all of the patients' sera tested regardless of the site (liver abscess vs. colitis) or geographic region that the amebic infection had occurred.     

Antigens of Entamoeba histolytica recognized by immune sera from liver abscess patients

Immune sera from 11 patients cured of amebic liver abscess was used to identify antigens of Entamoeba histolytica. Strain HM1-IMSS, among the most virulent in axenic culture, was used. The 37 and 90 Kd antigens were surface glycoproteins as indicated by lactoperoxidase iodination and by Concanavalin A blotting; the 59 Kd antigen was a mannose containing glycoprotein that did not appear to be on the cell surface. Western blots of 11 different immune sera revealed specific binding of immune IgG to 9 amebic proteins. Most frequently recognized proteins were of molecular weight 37, 59, and 90 Kd. The immunoblot pattern in 5 patients was unchanged for up to 30 months post-treatment for liver abscess.     

Differences in complement-mediated killing of Entamoeba histolytica between men and women--an explanation for the increased susceptibility of men to invasive amebiasis?

Men are more than 7 times more likely to develop amebic liver abscess or amebic dysentery caused by Entamoeba histolytica than women. Because the complement system could play a key role in controlling amebiasis, we determined whether serum from men and women differ in the ability to kill amebic trophozoites. We found that serum from women was significantly more effective in killing E. histolytica trophozoites than serum from men, and this killing was complement dependent. Our results provide a possible explanation for the differential susceptibility of men and women to amebic liver abscess and amebic colitis.     

Specific detection of Entamoeba histolytica DNA by hemolysin gene targeted PCR

Diagnostic differentiation of pathogenic Entamoeba histolytica from non-pathogenic Entamoeba dispar is of great clinical importance. We have developed and evaluated a new polymerase chain reaction (PCR) assay (haemo-PCR) based on the novel E. histolytica hemolysin gene HLY6. The specificity of this assay was confirmed by analyzing different Entamoeba species, faeces samples, human and bacterial DNA, and digestion of amplification products with appropriate restriction enzymes. The sensitivity was confirmed by serial dilutions of E. histolytica HM-1:IMSS DNA in the excess of human DNA. Totally, 45 clinical samples were analyzed by the haemo-PCR assay including amoebic liver abscess (ALA) fluids from 23 patients suspected for amoebiasis, four faeces samples containing E. histolytica and E. dispar, and positive and negative controls. The results were compared with those obtained with PCRs for cystein-rich surface protein (P30) and small subunit ribosomal RNA (ssu rRNA) genes. The haemo-PCR gave a positive result in 18 (89%) ALA fluids compared with 14 (77%) and five (28%) by PCR for p30, and ssu rRNA, respectively. PCR products were obtained only from specimens containing E. histolytica DNA. The haemo-PCR assay was therefore found to be a valuable diagnostic tool for identification of E. histolytica infections both in faeces and ALA samples.     

Defective production of reactive oxygen intermediates (ROI) in a patient with recurrent amebic liver abscess

Previously, we reported the case of a man in the fourth decade of life afflicted with three independent episodes of amebic liver abscesses over a period of 4 years. Previous evidence has indicated that the cellular immune response is involved in protection against recurrent invasive amebic infection, and macrophage-mediated effector mechanisms appear important for host resistance to Entamoeba histolytica infection. The aim of the present work was to investigate locomotor activity and oxidative burst function of peripheral mononuclear cells of this individual after healing of the third amebic liver abscess. A locomotion assay using Boyden chemotaxis chambers and the respiratory burst evaluated by chemiluminescence were performed in both mononuclear phagocytes (MPs) and polymorphonuclear (PMN) leukocytes. Levels of salivary IgA and serum IgG anti-amebic antibodies were followed during 48 months after the second amebic liver abscess. Results obtained showed a deficiency in MP but not in PMN leukocyte respiratory burst. Respiratory burst is a major microbicidal mechanism in MP leukocytes; this also has been considered as a host resistance strategy against E. histolytica. It may be at least one risk factor in our patient that was responsible for recurrence of amebic liver abscess.     

Usefulness of multiplex-PCR for identification of Entamoeba histolytica and Entamoeba dispar

We evaluated the usefulness of a multiplex-PCR method for differentiation of Entamoeba histolytica and Entamoeba dispar, which are morphologically indistinguishable species. Cultured trophozoites of E. histolytica HM-1: IMSS and E. dispar SAW were used as the positive control. Seven human fecal samples, from which E. histolytica-like cysts were detected by microscopic examination, and three intestinal protozoan parasites, Cryptosporidium parvum HNJ-1, Giardia intestinalis Portland-1, and Blastocytis hominis Nand II, were used for the evaluation of sensitivity and specificity of the PCR method. The other PCR method, which has been used for the diagnosis of amebic infections in Japan, was also performed by using the same samples for the evaluation. In comparison with the conventional PCR method, the multiplex-PCR showed 1) higher sensitivity, 2) the size of diagnostic fragments of PCR products was clearly different in both Entamoeba species, 3) it was possible to perform PCR using a single tube per sample, and then to save the amount of DNA polymerase, 4) no diagnostic amplification products were found in other intestinal protozoan parasites, and 5) E. histolytica specific fragment was amplified in all clinical samples examined. In conclusion, it is considered that the multiplex-PCR method is a useful tool for detection of both Entamoeba species DNA from fecal samples and for the distinction between E. histolytica and E. dispar.     

Amebiasis: Clinical implications of the recognition of Entamoeba dispar

Entamoeba histolytica was recently reclassified to recognize the existence of two genetically distinct but morphologically indistinguishable species: E. histolytica, the protozoan parasite that causes amebic dysentery and liver abscess, and Entamoeba dispar, a nonpathogenic intestinal parasite. Acceptance of this redefinition has dramatically changed both our understanding of the true epidemiology of E. histolytica and the optimal methods for diagnosing amebiasis. Molecular-based diagnostic tests using polymerase chain reaction (PCR) to amplify amebic DNA or enzyme-linked immunosorbent assay (ELISA) to identify amebic antigens in stool samples have been developed to distinguish infection with E. histolytica from infection with E. dispar. Because of its ability to differentiate strains of E. histolytica, PCR is a very useful research tool. Only the ELISA-based test is simple to perform, making it clinically useful in the developing world. To avoid unnecessary treatment of individuals infected with E. dispar, the World Health Organization has stressed the importance of making a specific diagnosis of E. histolytica infection (not E. histolytica/E. dispar) before treating for amebiasis.     

A recurrent case of amebic liver abscess seventeen years after the first occurrence

A 49-year-old male who had been diagnosed as having amebic liver abscess when he was 32-year-old was admitted to our hospital with fever and watery diarrhea. Ultrasonography and CT examination demonstrated a solitary abscess in the right lobe of the liver. Cysts of Entamoeba histolytica were detected in the stool and an aspiration of the liver abscess looked like anchovy paste. Serum amebic antibody by the IFA method was positive and the case was diagnosed as amebic liver abscess. The patient was treated with metronidazole, and percutaneous transhepatic abscess drainage was performed. The liver abscess decreased remarkably in size and serum amebic antibody was negative after the treatment. Recurrence of amebic liver abscess is rare and we report this case with some literature.