Additional antiprotozoal constituents from Cuphea pinetorum, a plant used in Mayan traditional medicine to treat diarrhoea

In addition to kaempferol and quercetin already found in the roots from Cuphea pinetorum, bioassay-guided fractionation of the crude extract of the aerial part of this species gave four flavonoid glycosides, quercetin-3-O-alpha-rhamnopyranoside, luteolin-7-O-beta-D-glucopyranoside, apigenin-7-O-alpha-L-rhamnopyranoside and apigenin-7-O-beta-D-glucopyranoside, as well as squalen and beta-sitosterol. In vitro antiamoebic and antigiardial activities of isolated compounds indicated that kaempferol is the principal antiprotozoal agent in C. pinetorum. Based on finding this antiprotozoal inhibitor, flavonoids were studied in order to elucidate structure-activity relationships. These data suggest that kaempferol may play an important role in antidiarrhoeal activity of C. pinetorum.     

兔颞颌关节骨关节病模型的建立及组织学观察

（1）目的 研究强力霉素对颞颌关节骨关节病的预防性治疗作用。（2）方法 应用胶原酶注射法制备30例兔颞颌关节骨关节病模型。随机分为实验组和对照组两组,实验组动物在胶原酶注射的次日起每天给予口服强力霉素,在第4,8和12周末每组分别处死5只动物,分别在光镜下和电镜下观察关节盘和关节软骨的病理变化。（2）结果 在第4周末,对照组动物关节盘血管增生明显,软骨细胞增生活跃,实验组只表现为轻微的病变,在第8周末,对照组病变更为典型,出现软骨裂隙和凝胶样物质脱落,而实验组出现病变的修复;在第12周末,对照组出关节病的发展,促进关节的自身修复,对早、中期的颞颌关节骨关节病有显著的治疗作用。     

Amebiasis in the newborn

Infestation withEntamoeba histolytica is especially common in areas with low socioeconomic status. Extra intestinal invasive involvement is more frequent in young children with significant mortality. This disease is rarely reported in the newborns. This 19-day-old newborn who was infected with orally given surgar solution is presented. He was successfully treated with ornidazole.     

Immunohistochemical characterization of human fulminant amoebic colitis

In cases of fulminant amoebic colitis we have determined the interactions between Entamoeba histolytica trophozoites and immune cells in order to better understand the pathophysiology of amoebic colitis. Eleven specimens of amoebic colitis and five specimens of colon without amoebic lesions were studied. Trophozoites and immune cells were located by topographic stains, histochemistry and immunohistochemistry. Trophozoites were seen in both damaged and undamaged areas of the colonic mucosa. Specimens of fulminant amoebic colitis showed: (a) an increase in IgA+, IgG+ B cells and neutrophils; (b) a reduction in IgM+ B cells, CD8+ T cells, macrophages, eosinophils and mast cells; and (c) no change in the number of NK and CD4+ T cells. The cellular infiltrate in amoebic colitis may represent the combined effects of amoebic monocyte locomotion inhibitory factor and switching of IgM+ B cells to IgG+ and IgA+ plasma cells, induced by amoebic antigens. Tissue damage in the absence of trophozoites may result from ischaemia or host immune responses.     

Colonic amoebiasis and spirochetosis: morphological, ultrastructural and microbiological evaluation

BACKGROUND: The present study reports on a prompt diagnosis of colonic amoebiasis with colonic spirochetosis by Brachyspira aalborgi and B. pilosicoli; such diagnosis allowed exclusion of other diseases and resolution of the case after specific treatment. METHODS AND RESULTS: A 37-year-old Italian man with a history of several months' mucosal diarrhea travelled to Greece, Romania and Tunisia. After his last trip he presented with an increase of up to 3-5 discharges daily, associated with bloody diarrhea, supporting the clinical suspect of inflammatory bowel disease. Colonoscopy revealed erosions from the cecum to the rectum, and ulcers both in the descending and sigmoid colon. Structures resembling amoebic trophozoites and sinusoidal microorganisms were observed in the colonic biopsies at histopathology and electron microscopy. Entamoeba histolytica DNA was detected by small-subunit rDNA polymerase chain reaction (PCR) from feces, rectal biopsies and isolated trophozoites. Spirochetes were identified from feces, colonic biopsies and cultures using a 16S rDNA restriction fragment length polymorphism-PCR specific for the detection of B. aalborgi and B. pilosicoli. After therapy, the patient was restored to health. CONCLUSIONS: The rapid identification of E. histolytica, B. aalborgi and B. pilosicoli using traditional and specific and sensitive molecular methods permitted an accurate diagnosis and a specific therapy. It is suggested that mixed infection by parasites and spirochetes might occur more frequently than expected: it would be of extreme interest and importance to intensify clinical findings, and one infection should not prompt the pathologist/clinician to stop looking.     

Hemolytic uremic syndrome associated with Entamoeba histolytica intestinal infection

Amebiasis secondary to Entamoeba histolytica (E. histolytica) continues to be a major source of morbidity and mortality worldwide, mainly in developing countries. An association between amebic dysentery and hemolytic uremic syndrome (HUS) has been mentioned, but a cause-and-effect relationship has never been confirmed. We report the case of an 11-year-old healthy white female who developed severe bloody diarrhea after drinking contaminated unboiled water, developing classic HUS and requiring acute intermittent hemodialysis. The etiological study confirmed numerous cysts and hematophagous trophozoites of E. histolytica on stool smear, but without evidence of other pathogens. This report contributes to the concept that classic post-diarrheal HUS, usually related to colitis secondary to enterohemorragic Shiga-toxin producing Escherichia coli (E.coli) strains, may be associated with other pathogens, including E. histolytica. Additional information regarding mechanisms of virulence of E. histolytica and host immunological reaction is needed to clarify the temporal association of these two disorders (HUS and amebiasis).     

Amebic liver abscess rupturing into the lesser omentum space

A case of an amebic abscess localized in the lesser omentum is reported. There was no sign of a liver abscess in the imaging examination or the operative findings. However, it is likely that the amebic infection occurred after a liver abscess ruptured into the abdominal cavity. Early diagnosis and therapy are required when an abscess of unknown origin borders the liver, given the possibility of amebic abscess.     

Human amoebic hepatic abscess: in situ interactions between trophozoites, macrophages, neutrophils and T cells

Amoebic liver abscesses (ALA) are the most frequent and severe extraintestinal clinical presentations of amoebiasis. During the early establishment of amoebae in the liver parenchyma, as well as during the extension of the tissue necrosis, parasites interact with the parenchymal liver cells and, as a consequence of these interactions, hepatocytes can be destroyed and host immune cells can become activated. However, little is known about the nature of these interactions in the liver or about the factors involved in the local immune response. In this investigation we studied the localization of Entamoeba histolytica trophozoites, TCD4+, TCD8+ cells, CD68+ macrophages and CD15+ neutrophils in human ALA using immunohistochemical techniques. Trophozoites were found close to undamaged hepatocytes in both lysed and non-lysed areas with either sparse or abundant inflammatory infiltrate. CD8+ cells were more abundant than CD4+ T cells. CD 68+ macrophages and CD15+ neutrophils were also detected, suggesting that neutrophils, macrophages and T cells might be related to the local host immune mechanisms in ALA. We also found that E. histolytica possesses proteins recognized by antibodies raised against inducible nitric oxide synthase.     

Direct amplification of <Emphasis Type="Italic">Entamoeba histolytica</Emphasis> DNA from amoebic liver abscess pus using polymerase chain reaction

An important and serious complication of intestinal infection with Entamoeba histolytica is the involvement of the liver (hepatic amoebiasis). Hepatic amoebiasis is usually diagnosed by the clinical picture (pain in the right upper quadrant and fever), ultrasound examination and positive serology. However, none of these tests are definitive and the picture overlaps with pyogenic liver abscess caused by bacteria. It is for this reason that the feasibility of using polymerase chain reaction (PCR) for the detection of E. histolytica DNA in liver abscess pus was investigated. A comparative study was done to verify the sensitivity of ten pairs of primers specific for detecting E. histolytica in stools. Samples of liver abscess pus from 22 serology-positive patients were collected under ultrasound guidance; and these were used directly in PCR assays without any prior pre-treatment of the samples. Of the ten pairs of previously published primers tested, two pairs of primers (P1 + P2 and P11 + P12) were found to give 100% sensitivity. Based on these results, we recommend that PCR assay can be successfully used to confirm the diagnosis of amoebic liver abscess with the primers identified. Received: 12 March 2000 / Accepted: 18 April 2000     

Treatment of symptomatic amebic colitis in human immunodeficiency virus-infected persons

While most Entamoeba histolytica appearing in male homosexuals infected with human immunodeficiency virus (HIV) is considered non-invasive in Western countries, and treatment of amebiasis in these persons has received very little attention, in Japan some male homosexual amebiasis patients infected with HIV complain of symptoms attributable to E. histolytica infection. We investigated whether symptomatic E histolytica amebic colitis in HIV-infected persons requires higher doses or longer duration of antiamebic drug therapy than in non HIV-infected patients. Four symptomatic amebic colitis patients infected with HIV-1, three of them severely immunocompromised, with CD4 cell counts <200/mm³, were treated with oral metronidazole: 1500 mg a day for 10 days in 2 patients, 1000 mg a day for 10 days in 1 patient, and 1000 mg a day for 6 days and then 750 mg for 4 days in 1 patient, and good therapeutic results with no side effects were obtained. This indicates that symptomatic amebic colitis in HIV-infected persons can be successfully treated with metronidazole at the same dose and duration of treatment used in non-HIV-infected persons.