Entamoeba histolytica: inflammatory process during amoebic liver abscess formation involves cyclooxygenase-2 expression in macrophages and trophozoites.

It has been demonstrated that expression of cyclooxygenase-2 (COX-2) isoform is induced by Entamoeba histolytica in macrophages and polymorphonuclear cells during amoebic liver abscess (ALA) formation in hamsters. Trophozoites present in the lesion were also positive for COX-2 signal. However, no cross reactivity of the anti-COX-2 antibody with protein extract of cultivated trophozoites was found. To clarify if trophozoites are involved in PGE(2) production during ALA development, COX-2 expression was detected by in situ hybridization and RT-PCR in liver tissue from intrahepatically infected hamsters. COX-2 mRNA was in polymorphonuclear cells since 4h postinfection, and subsequently, local macrophages expressed COX-2 mRNA in a similar way. Additionally, a positive signal for COX-2 mRNA expression was detected in E. histolytica trophozoites, suggesting that, in vivo, parasite COX expression may be an important mechanism to promote inflammation.

Use of antipsychotic drugs in nursing homes: current compliance with OBRA regulations.

OBJECTIVE: To examine the degree and patterns of compliance with the Omnibus Budget Reconciliation Act (OBRA) regulations regarding the use of antipsychotic drugs in nursing homes. DESIGN: Retrospective chart review of all resident records. PARTICIPANTS: Eight nursing homes: five community, two county-owned, and one university-affiliated Veterans Administration facility. MEASUREMENTS: A structured assessment instrument to track compliance with each aspect of the OBRA regulations regarding antipsychotic drug use. RESULTS: A total of 1573 nursing home residents' pharmacy records were reviewed between August 1994 and March 1996. Two hundred seventy-nine residents were actively taking antipsychotic medications (prevalence = 17.7%). Mean compliance greater than 70% was found for (1) appropriate diagnostic indication (mean = 70.9%), (2) dosage within recommended limits (mean = 90.1%), and 3) documented appropriate target symptoms (mean = 90.4%). Dosages were more likely to exceed limits in those patients with histories of major mental illness, particularly schizophrenia. CONCLUSIONS: Nursing homes were better able to comply with those guidelines that are most specific. Educational interventions now need to focus on behavioral interventions, monitoring of adverse effects, and efficacy. These data are useful in establishing threshold levels of performance and can be used by nursing homes for continuous quality improvement. OBRA continues to impact neuroleptic drug prescribing practices in nursing homes significantly.

Prospective study of Entamoeba dispar infection in a cohort of mothers and their infants: relationship to serum antibody response.

The sera of cohorts of newborn infants and their mothers, characterized as cyst passers of Entamoeba with nonpathogenic zymodemes (E. dispar) and seropositive for amoebic antigens, were analyzed. Both cohorts were followed for a period of 12 months by microscopic examination of feces and determination of serum anti-amoebic antibody titers using the indirect hemagglutination assay. Control groups (noncyst passer mothers and their infants) were included and followed. To characterize antigens involved in the induction of IgG and IgA antibody responses, Western blots of serum from all participants were tested and immunoplots of the frequency of antigenic recognition were constructed. Results of clinical follow-up and microscopic examination of feces showed that during the 12-month period none of the cyst passer mothers had episodes of diarrhea attributable to E. histolytica invasion; five of 21 children of cyst passer mothers became infected during the study, five of five infected children developed serum antiamebic antibodies (titers 1:64-1:128); none of the cohort of children from cyst passer mothers had diarrhea due to E. histolytica. Western blot analysis showed that there are antigenic fractions that induce serum antibodies of the IgG and IgA classes against E. dispar very early in the host-parasite relationship. Our results suggest that mechanisms of antibody induction different from intestinal invasion may be operating in amebic infection. Intestinal absorption of antigen, systemic reflection of secretory antibody response, and priming of newborns by maternal anti-idiotypic antibody transfer are discussed.

Entamoeba histolytica: antibody response to recent and past invasive events.

Sero-epidemiological data from endemic amoebiasis areas are difficult to evaluate because the serology of individuals affected by an active process of Entamoeba histolytica tissue invasion is, at present, almost impossible to distinguish from that of individuals who have had an invasive event in the past. The present study compares serum antigenic recognition frequencies among three groups of individuals with different infective conditions: amoebic liver abscess patients; asymptomatic cyst passers; and individuals who have had amoebic liver abscess from one to three years before the study. Control groups consisted of Mexican and Canadian healthy adults. Western blots of E. histolytica membrane extract antigen were reacted with sera from the studied individuals, recognition frequency values were calculated and immunoplots of frequency differences were constructed. The results obtained suggest that the identification and purification of antigenic fractions, which are frequently recognized by sera of amoebic liver abscess patients (136, 132, 93, 70 and 62 kDa), or preferentially associated with past invasive events (144, 140 and 49 kDa), or related to the E. histolytica cyst passer condition (62 and 136 kDa), are important improvements in the use of serology for diagnosis and epidemiological studies in endemic areas of amoebiasis.

Western blot of Entamoeba histolytica antigenic fractions: reactivity analysis with sera from intestinal amoebiasis patients.

The reactivity of sera from acute-phase intestinal amoebiasis patients (two weeks evolution) was studied to determine which of the Entamoeba histolytica antigens are most frequently immunogenic. Sera were examined by means of immunoelectrotransferase assay using crude extract of HM1:IMSS E. histolytica trophozoites. Three populations of clinically healthy adults from Mexico, Canada and Germany, with no evidence of parasites in faeces, were used as controls. The frequency of antigen recognition was analysed. In ailing individuals, the bands of 23, 24, 26 and 51 kDa were recognized most frequently (65 and 60%) followed by the 62 kDa band (56%). The combination of some of these bands, namely 3.4, 4.1 and 6.7, with molecular weights of 62, 51 and 24 kDa, increased the recognition frequency of patients to 91.4%. These results constitute a first but important step towards the design of more accurate methods for the successful immunodiagnosis and epidemiology of acute intestinal amoebiasis.

Inhibition of adhesion process mediated by anti-Entamoeba histolytica specific monoclonal IgA antibodies.

Adhesion of trophozoites to target cells in the host intestine is the first of three consecutive steps (adherence, cytolytic effect and phagocytosis) involved in the invasion of colonic tissue by E. histolytica. To investigate the possible participation of the local secretory immune response in the interference with this early host-parasite relationship, we produced IgA monoclonal anti-E. histolytica antibodies to test their capacity for blocking the adhesion process in vitro (MDCK and HT-29 cell lines) and in situ (colonic mucosa from Balb/c mice and gerbils). Results demonstrate that the monoclonal antibodies tested inhibited trophozoite adherence both in vitro and in situ. This suggests that the local antibody response may play an important role in protection against the invasive process in intestinal amebiasis.

[Report on the therapeutic use of rimantadine and amantadine]. / Reporte sobre el uso de la rimantadina y la amantadina.

A discussion is carried out about the experiences with the application of rimantadine and amantadine to patients with influenza. The basic general results consisted in the fact that 2 of the 74 patients treated had a high cure percent (> 68.0%) within the first 72 hours after using the drug. No new diseased were found among the 40 contacts to whom chemoprophylaxis was applied. There were only 3.9% adverse reactions among the total number of people treated with amantadine.

[Experience with the use of amantadine for the control of an influenza outbreak at an Elderly Home]. / Experiencias del uso de la amantadina en el control de un brote de gripe en un Hogar de Ancianos.

A study of an outbreak of acute respiratory disease was done at the "Carlos Font Pupo" Old People's Home. Las Tunas Province, where 30 diseased old individuals were detected; grippe was diagnosed to two of them. General attack rate was 8.6%. Curative treatment with amantadine was administered to 29 old patients and chemoprophylaxis to 26, for a total of 55 old individuals treated. The evolution of the patients was satisfactory and none new case was observed. Diarrhea was the only one secondary reaction observed in a patient under chemoprophylactic treatment. The need to carry on performing similar studies is pointed out.

[Intravesical echography. I. Anatomical correlation]. / Ecografía intravesical. I: Correlación anatómica.

The scan images of the normal bladder were obtained by intravesical ultrasonography (IVU) and the ultrasonographic-anatomic correlation were defined based on 179 procedures. Except in bladder cancer, IVU did not prove to be useful in the evaluation of other bladder conditions or adjacent structures, including gynecological disorders.

Ureolytic Citrobacter freundii infection of the urine as a cause of dissolution of cystine renal calculi.

We report a case of cystinuria with staghorn renal lithiasis in a solitary right kidney and chronic renal failure. Right nephropyelolithotomy was performed and although 29 renal calculi were extracted many stones remained in situ. A permanent nephrostomy was left in the kidney. Several months later the urine was infected chronically with a ureolytic Citrobacter freundii bacteria and urinary pH oscillated between 8.0 and 9.2. Spontaneous dissolution of the cystine calculi was observed and many tiny fragments of cystine were expulsed through the nephrostomy, following which renal function improved. Despite the conditions favoring struvite calculi, formation did not occur.