[In vitro effect against Giardia of 14 plant extracts]. / Efecto antigiardiásico in vitro de 14 extractos de plantas.

OBJECTIVE: To investigate antigiardiasic activity in plants used in Mexico as antidiarrheics and/or antiparasitics. MATERIALS AND METHODS: Fourteen species were evaluated. The antigiardiasic activity was measured in vitro in a blinded fashion using trophozoites of Giardia duodenalis incubated with plant extracts. The viability of trophozoites was ascertained using MTT (3-[4,5-dimethylthiazol-2-il]-2, 5-diphenyl tetrazolium bromide) which is reduced to MTT-formazan by the activity of live trophozoites. The reduced MTT was extracted with an acidified alcohol (2-propanol with HCI 0.04 M) and measured in a spectrophotometer at 570 nm. Negative (trophozoites without extract) and positive controls (incubated with tinadazol) were included. RESULTS: The scientific and trivial names of the plants are given (trivials in Spanish marked by an asterisk). They had the following trophozoite mortality (mean +/- SD in percent): Justicia spicigera (muicle*) = 91 +/- 0.5; Lipia beriandieri (oregano) = 90 +/- 0.6; Psidium guajava (guava) = 87 +/- 1.0; positive control of tinidazol = 79 +/- 1.9; Punica granutus (granado*) = 78 +/- 1.3; Magnifera indica (mango) = 77 +/- 1.0; Plantago major (lante*) = 76 +/- 1.2; Cupressus semperbirens (cipres) = 73 +/- 1.2; Castella tormentosa (chaparro amargoso*) = 70 +/- 0.7; Hematoxilon campechanum (palo de Campeche*) = 67 +/- 1.2. Without or with a low mean activity were Prosopis juliflora (mesquite*) and Rizophora mangle (mangle*) with 0%, Oriza sativa (rice) with 5%, Capsicum annum (pimiento*) with 21% and Persea americana (avocado) with 23%. There were no associations of the antigiardiasic effect with concentration or osmolality of the extracts. CONCLUSIONS: A clear in vitro antigiardiasic effects was seen in nine species. Three of them were superior to tinidazol which is a drug of common use in the treatment of giardiasis.

[Giardia duodenalis: analysis of malic enzyme expression with isoelectric focusing]. / Giardia duodenalis: análisis de la expresión de la enzima málica mediante isoelectroenfoque.

We wish to propose a data base of the isoelectric point (pl) for Giardia duodenalis isozymes [corrected]. As a contribution to this end we characterized by electrophoresis the isozymes of the malic enzyme (ME) of ten G. duodenalis isolates from Mexican children. Isoelectric focusing was performed in a vertical system using a one mm slab gel of 5.5% acrylamide prepared with 6.5% carrier ampholytes, pH 3-10, and 10% glycerol. Each test sample (10 micrograms) and a series of protein markers of known pl were applied in duplicate, and a minimum of six samples for each isolate were prefocused at 1.5 W, 200 V for 0.25 hour and focused at 2100 volt-hour, 3 W, 800 V. With the regression equation for protein markers Y = 1.886 + 5.709(X) (standard error for X = 0.001 and Y = 0.136), we calculated the pls for each isozyme of the malic enzyme detected in the G. duodenalis isolates. The pl of the isozymes were between 5.70-7.63 and the clone INP-100588-CMG1 was different from the parental isolates in three isozymes: pl 7.34, 7.16 and 6.99. The determination of isoelectric points of the isozymes of other enzymes of Giardia duodenalis should be a useful tool for the detection of their genetic variability by numeric comparison.

[Fascioliasis in children. A study of 10 cases]. / Fasciolosis en los niños. Estudio de 10 casos.

These are the observation found in ten children with fascioliasis diagnosis at the Servicio de Parasitología, of the Instituto Nacional de Pediatría, from 1979 to 1990; six children in scholar age; one prescholar and three teenagers; only one was female. Four of them lined at the State of Mexico; three at Morelos; one at Puebla, another one at Oaxaca and the other one at Mexico City. In nine of the watercress eaten was confirmed. The most important clinic manifestations were: fever, weight lose, paleness, hepatomegaly, hiporexia, right hypochondrium pain and diarrhoea. Diagnosis was established by: counterimmunoelectrophoresis, indirect haemagglutination and there were found eggs by simple sedimentation, Ritchie's method and microscopic study of duodenal sample. Leukocytes counts were between 11,000 and 34,000/mm3. Eosinophils were to 77% with 24,430 totals. Only in three of them haemoglobin was found under 9 g/dL. All of them had hypergammaglobulinemia. In nine patients the alkaline phosphatase was found in higher levels; only in three of them, transaminase, oxalacetic and glutamic piruvic were found in higher levels. The most effective drug in the treatment was dehidroemetine.

[Trichinosis in children. A report of 8 cases]. / Triquinosis en el niño. Informe de 8 casos.

A comparative study between 8 cases of trichinosis and 16 of typhoid fever is presented in this paper; all of them were attended in the INP during the period from 1970 to 1990. The diagnosis was established under epidemiologic, clinic and laboratory bases. The range of age of these patients was from 10 to 14 years, from low socioeconomic status; half of the cases had history of in take of infested pork meat. The most characteristic symptoms were: fever, myalgia and limitation of muscular movements. Leukocytosis in addition to eosinophilia were found in 7 cases. Correlation with indirect hemagglutination, CIEF positive test for Trichinella spiralis and biopsy of muscle was done. Thiabendozole therapy was utilized for treatment with satisfactory evolution, except in one case that developed progressive and fatal neurologic damage.

[Serum levels of IgE in children with invasive amebiasis]. / Niveles de IgE sérica en niños con amibiasis invasora.

In order to determine whether an elevation of the IgE serum level exist in children with invasive amebiasis when compared with a control group, a prospective, observational and descriptive study was performed on 20 patients from the problem group and 21 from a control group, where the possibility of other causes which could raise the IgE levels were dismissed. This antibody was measured in serum and compared with the reported levels of mexican and foreign populations. A notable elevation of the IgE level was found in the studied groups, without any significant differences between them. It wasn't demonstrated that the serum level is as high as immunological response against E. histolytica.

Excystation and culture of Giardia spp. from human source.

In this paper, we report the hatching of Giardia spp. trophozoites from purified cysts harvested in Sheather's solution from human feces. Isolated cysts were induced by acidic Hank's Balanced Salt Solution (HBSS), incubated at 37 degrees C for 30 minutes, concentrated by centrifugation and washed with pH 7.5 HBSS. The cysts were placed in 8 ml. culture medium (Pancreatic digest of casein and yeast extracts) supplemented with human serum and bile in borosilicate glass tubes with screw caps. Trophozoite excystation was scanned in a Commandon chamber filled with the suspension, sealed with a cover glass and vaseline. The trophozoite emergence was recorded with phase contrast in a photomicroscope. The excystation began within the first 3 minutes, after inoculation into medium. The trophozoites emerged trough a small hole at one end of the cyst and simultaneously began cellular division, the whole process required 5-30 minutes. The trophozoites attached themselves to the walls of the culture tube, permitting the replacement and removal of contaminants without dislodging them from the tube walls. The isolates MM-INP and MG-INP have been maintained at 37 degrees C for more than six months.

Susceptibility to genotoxic effects of niclosamide in human peripheral lymphocytes exposed in vitro and in vivo.

Niclosamide added in 2-h pulses to lymphocyte cultures induced a small clastogenic effect in one blood donor, while in two other blood donors it inhibited mitosis. In the presence of the 'S9' metabolic activation system, the antihelminthic drug exhibited a dose-related increase in clastogenicity in 2 of 4 blood samples. A weak dose-related increase in S.C.E. was observed only in the lymphocytes from one of these blood samples. From 5 patients treated with niclosamide, 3 showed an increase in chromosomal aberrations after treatment; in none of them was an induction of S.C.E. observed. These results suggest differences in lymphocyte susceptibility to the genotoxic effects of therapeutic drugs and also underline the need for evaluating chromosomal aberrations as well as SCE in any study of genotoxic substances.

[Frequency of vulvovaginitis in girls with intestinal enterobiasis]. / Frecuencia de vulvovaginitis en niñas con enterobiasis intestinal.

The study included 415 female patients with the diagnosis of enterobiasis seen at the Hospital del Niño, DIF. Vulvovaginitis was found in 78 cases (18%), with definite predominance in the school-age group. The clinical manifestations in order of frequency were: perianal and vulvar pruritus, abdominal pain, leukorrhea and vulvar edema. Graham's perianal and perineal smear method was performed with 100% positiveness in personal and 85% in perineal smears. The treatment should be directed to improve the family sanitary habites and the prescription of the choice drug to the patient and to his family. The following drugs are quite as effective: piperazine citrate, pyrvinium pamoate, pyrantel pamoate and mebendazole. The physician should use the drug that better fits the patients convenience, keeping in mind the easy determination of the dose and the cost in order to offer the patient and his family the best choice.

[Evaluation of the effectiveness of thiabendazole, pyrantel and mebendazole in the treatment of necatoriasis in children]. / Evaluación de la efectividad del tiabendazol, pirantel y mebendazol en el tratamiento de la necatoriasis en los niños.

A study was made of 48 patients from the different departments of the Hospital del Niño, DIF, in which hookworm eggs were demonstrated by qualitative coproparasitoscopic study (CPS). During the study, quantitative CPS was practiced on them by Stoll's dilution and the Harada-Mori technique, for the identification of the hookworm larvae. They were divided into three groups: A, B and C (16 patients in each group); the study was single-blind. The effectiveness of the evaluated drugs was based on the disappearance or diminution of hookworms eggs in the CPS (Stoll) practiced 2 weeks after the drug treatment had finished. The work was done with patients parasitized by Necator americanus (verified by the Harada-Mori technique). The A group was given pyrantel pamoate; the B group, thiabendazole and the C group, mebendazole. The results obtained were statistically processed by means of X2 proportions. There was no significant difference between the three groups when a light to moderate necatoriasis was treated; when a massive infection was involved, there was a significant difference and it was found that the best drug was pyrantel pamoate administered at the dose of 20 mg/kg/day/3 days. There were few side effects in the three groups, but they were not sufficient to cause suspension of the treatment. The cheapest drug was thiabendazole.

[Strongyloidiasis in children. Report of 17 cases]. / Estrongiloidósis en el niño Communicación de 17 casos

Results from the study of 17 strongyloides infections without other associated parasitoses seen at the Hospital del Niño, IMAN between January 1971 and June 1976 are reported. The most affected age groups were of pre-school children with no sex predominance. Patients came from the states of Veracruz, Guerrero, Hidalgo, Michoacín, Morelos, San Luis Potosí and Sinalos. Different degrees of malnutrition were found in 10 out of the 17 patients. Predominant signs or symptoms were as follows: paleness, nausea, vomiting, diarrhea, bloody and mucous stools, hyporexia, hyperthermia, pain and abdominal distention. Ferreira's method for coproparasitoscopic examination was the most efficient to show Strongyloides sterocarlis larvae. Moderate eosinophilia from 10 to 14% was found in most of the patients. Treatment was carried out with thiabendazole in most of the patients. This drug proved to be quite effective in the treatment for strongyloidoisis.

[Subcutaneous cysticercosis. 8 cases in children]. / Cisticercosis subcutánea. Informe de ocho casos en niños

Observations in eight patients with subcutaneous or submucous cysticercosis studied at the "Hospital del Nino, IMAN", between November 1970 and June 1975 are reported; the age of the patients varied between 4 and 14 years; six of them were females and 2 were males. One of the patients was found to have C. cellulosae in the central nervous system as well. In the presence of subcutaneous and submucous nodules, cysticercosis should be considered in the differential diagnosis, and anatomic and histopathological documentation should be sought; in cases in which cysticercosis is verified, the patient should be carefully studied, to rule out the presence of C. cellulosae in other locations, mainly the central nervous system.