We present a critical analysis of the generalized use of the "impact factor". By means of the Kruskal-Wallis test, it was shown that it is not possible to compare distinct disciplines using the impact factor without adjustments. After assigning the median journal the value of one (1.000), the impact factor value for each journal was calculated by the rule of three. The adjusted values were homogeneous, thus permitting comparison among distinct disciplines.

OBJECTIVE: To evaluate the therapeutic efficacy of oxamniquine and praziquantel, the two most clinically important schistosomicide drugs, and to compare the accuracy of faecal examination with the accuracy of oogram in testing for Schistosoma mansoni infection. METHODS: In a triple-masked and randomized controlled trial, 106 patients infected with S. mansoni were randomly allocated to one of three statistically homogeneous groups. One group was given 60 mg/kg praziquantel per day for three consecutive days, another was given two daily doses of 10 mg/kg oxamniquine, and the placebo group received starch. Faecal examinations (days 15, 30, 60, 90, 120, 150, and 180 after treatment) and biopsy of rectal mucosa by quantitative oogram (days 30, 60, 120, and 180) were used for the initial diagnosis and for evaluating the degree of cure. The chi2 test and the Kruskal-Wallis test were used to compare variables in the three groups. Survival analysis (Kaplan-Meier) and the log-rank test were used to evaluate the efficacy of the treatments. FINDINGS: The sensitivity of stool examinations ranged from 88.9% to 94.4% when patients presented with >5000 S. mansoni eggs per gram of tissue (oogram); when the number of eggs dropped to <1000 eggs per gram, sensitivity was reduced (range, 22.7-34.0%). When cure was evaluated by stool examination, oxamniquine and praziquantel had cure rates of 90.3% and 100%, respectively. However, when the oogram was used as an indicator of sensitivity, the oxamniquine cure rate dropped dramatically (to 42.4%), whereas the rate for praziquantel remained high, at 96.1%. CONCLUSIONS: Praziquantel was significantly more effective than oxamniquine in treating S. mansoni infection. The oogram was markedly more sensitive than stool examinations in detecting S. mansoni eggs and should be recommended for use in clinical trials with schistosomicides.

OBJETIVO: Evaluar la eficacia terapéutica de la oxamniquina y el prazicuantel, los dos esquistosomicidas más importantes a nivel clínico, y comparar la precisión del examen coprológico y la precisión del oograma como medios diagnósticos de la infección por Schistosoma mansoni. MÉTODOS: En un ensayo controlado y aleatorizado a triple ciego, se procedió a asignar aleatoriamente a 106 pacientes infectados por S. mansoni a alguno de los tres grupos estadísticamente homogéneos establecidos: a un grupo se le administraron 60 mg/ kg diarios de prazicuantel durante tres días consecutivos, a otro se le dieron dos dosis diarias de 10 mg/kg de oxamniquina, y al tercero, el grupo placebo, se le administró almidón. El diagnóstico inicial y la evaluación del grado de curación se basaron en los exámenes coprológicos (días 15, 30, 60, 90, 120, 150 y 180 después del tratamiento) y la biopsia de la mucosa rectal mediante oograma cuantitativo (días 30, 60, 120 y 180). Para comparar las variables en los tres grupos se utilizaron la prueba del chi-cuadrado y la prueba de Kruskal-Wallis, y la evaluación de la eficacia de los tratamientos se basó en el análisis de la supervivencia (Kaplan-Meier) y la prueba del rango logarítmico. RESULTADOS: La sensibilidad de los exámenes coprológicos fue del 88,9%-94,4% cuando los pacientes acudieron al médico con más de 5000 huevos de S. mansoni por gramo de tejido (oograma); en los casos en que el número de huevos caía por debajo de 1000 por gramo, la sensibilidad disminuía (intervalo: 22,7%-34,0%). Cuando la curación se evaluó mediante examen coprológico, la oxamniquina y el prazicuantel lograron tasas de curación de 90,3% y 100%, respectivamente; sin embargo, cuando se utilizó el oograma como indicador de la sensibilidad, la tasa de curación con oxamniquina descendió pronunciadamente (a 42,4%), mientras que la tasa correspondiente al prazicuantel siguió siendo alta, 96,1%. CONCLUSIÓN: La eficacia del prazicuantel fue significativamente mayor que la de la oxamniquina como tratamiento de la infección por S. mansoni. En lo que respecta a la detección de los huevos, el oograma fue mucho más sensible que los exámenes coprológicos, por lo que se recomienda el uso del primero en los ensayos clínicos de esquistosomicidas.

OBJECTIF: Evaluer l'efficacité thérapeutique de l'oxamniquine et du praziquantel, les deux antibilharziens les plus importants au plan clinique, et comparer le degré d'exactitude de l'examen coprologique à celui de l'oogramme pour la recherche des infections à Schistosoma mansoni. MÉTHODES: Dans un essai contrôlé randomisé à l'aveugle, 106 patients infectés par S. mansoni ont été répartis aléatoirement dans trois groupes statistiquement homogènes. L'un des groupes a reçu 60 mg/kg de praziquantel par jour pendant trois jours consécutifs, le suivant deux doses quotidiennes de 10 mg/kg d'oxamniquine, tandis que le groupe placebo recevait de l'amidon. Le diagnostic initial et le degré de guérison ont été déterminés d'après l'examen coprologique (aux jours 15, 30, 60, 90, 120, 150 et 180 après traitement) et la biopsie de muqueuse rectale pratiquée pour obtenir un oogramme quantitatif (aux jours 30, 60, 120 et 180). Le test du <FONT FACE=Symbol>c</FONT>2 et l'analyse de variance (test de Kruskal-Wallis si nécessaire) ont été utilisés pour comparer les variables dans les trois groupes. L'évaluation de l'efficacité des traitements a été faite par l'analyse de survie (méthode de Kaplan-Meier) et la méthode du log-rank. RÉSULTATS: L'examen coprologique avait une sensibilité de 88,9 % à 94,4 % quand le nombre d'œufs de S. mansoni par gramme de tissu (oogramme) était >5000 ; la sensibilité était diminuée quand le nombre d'œufs tombait en-dessous de 1000 par gramme (22,7-34,0 %). Quand la guérison était appréciée par examen coprologique, l'oxamniquine et le praziquantel avaient des taux de guérison de respectivement 90,3 % et 100 %. En utilisant l'oogramme comme indicateur de la sensibilité, le taux de guérison avec l'oxamniquine s'effondrait à 42,4 %, tandis que le taux de guérison par le praziquantel se maintenait à 96,1 %. CONCLUSION: Le praziquantel s'est montré significativement plus efficace que l'oxamniquine dans le traitement de l'infection à S. mansoni. L'oogramme s'avère bien plus sensible que l'examen coprologique pour la recherche des œufs de S. mansoni et il convient de le recommander dans les essais cliniques des antibilharziens.

Camundongos albinos não-isogênicos, normais ou infectados com 30 cercárias de Schistosoma mansoni (cepa LE) foram submetidos a hepatectomia parcial (65%) na fase aguda (70 dias) ou crônica (160 dias) da doença. Um grupo de animais infectados foi tratado, na fase aguda, com 400 mg/kg oxamniquine antes da hepatectomia. Animais não infectados, infectados e tratados mas não hepatectomizados, foram mantidos como controles. A regeneração hepática foi avaliada pela incorporação de timidina tritiada, injetada peritonealmente em animais hepatectomizados ou não, 24 horas após cirurgia. Os resultados mostraram que a remoção de 65% do parênquina hepático, na fase aguda, levou a um aumento estatisticamente significativo da incorporação de timidina, quando comparado com os animais controles (não infectados e hepatectomizados). Este fenômeno não foi observado na fase crônica. O tratamento com oxamniquina, administrado na fase aguda, levou a uma diminuição da taxa de incorporação de timidina, 160 dias após infecção (90 dias após tratamento) e 24 horas após hepatectomia. Os dados obtidos sugerem que a infecção com S. mansoni representa um estímulo considerável para a capacidade regeneradora do fígado na fase aguda, mas não na fase crônica da doença.

Outbred male albino mice normal or infected with 30 cercariae of Schistosoma mansoni (LE strain) were submitted to 65% hepatectomy during the acute (70 days) and chronic phase (160 days) phases of the disease. A group of the infected animals was treated with 400 mg/kg of oxamniquine during the acute phase before hepatectomy. Non-infected, infected and treated but not hepatectomized animals were kept as controls. Hepatic regeneration was evaluated by incorporation of tritiated thymidine, intraperitoneally injected into non-hepatectomized and hepatectomized animals, 24 hours after surgery. The results showed that removal of 65% of the hepatic parenchyma, during the acute phase, led to a statistically significant increase of thymidine incorporation, when compared with the uninfected hepatectomized controls. This phenomenon was not observed at the chronic phase. Treatment with oxamniquine administered during the acute phase led to a decrease in thymidine incorporation rate 160 days after infection (90 days after treatment) and 24 hours after hepatectomy. The data suggest that infection with S. mansoni represents a considerable stimulus for the regenerative capacity of the liver during the acute, but not the chronic phase of disease.

Estudamos a modulação da resposta inflamatória granulomatosa em torno de ovos de S. mansoni no fígado de camundongos albinos (Mus musculus), que receberam 7% de etanol como única fonte de líquido. Os animais que receberam etanol aos 60 e 90 dias após a infecção apresentaram granulomas menores do que os controles, quando sacrificados aos 120 dias após a infecção. Não houve diferença no diâmetro dos granulomas quando a ingestão de etanol foi iniciada 4 meses antes e prolongada até 120 dias após a infecção. Nossos resultados indicam que a modulação da inflamação granulomatosa varia de acordo com o tempo e a duração da ingestão do etanol.

We studied the role of ethanol on the modulation of liver granulomata around Schistosoma mansoni eggs in mice. Albino mice, receiving 7% ethanol as the sole drinking liquid, at 60 and 90 days post-infection, presented smaller granulomata than controls did, when sacrificed at 120 days post-infection. No differences in diameters could be observed, when ethanol was given 4 months before up to 120 days after infection. The results suggested that modulation of schistosome granulomata by ethanol ingestion varies with time and duration of drug consumption.

A infecção de camundongos pelo Trypanosoma cruzi inibe a formação do granuloma hepático esquistossomótico. Este efeito imunodepressor ocorreu em camundongos com a fase aguda ou crônica da doença de Chagas, sendo os granulomas significativamente menores que nos animais controles. Os dados sugerem que a doença de Chagas deprime diretamente a imunidade celular.

Infection by Trypanosoma cruzi in mice depresses hepatic granuloma formation around Schistosoma mansoni eggs. This immunodepressive effect occurred in mice with Chagas' disease at the acute and/or chronic phases, granulomas being signijicantly smaller than those in Controls. Data suggest that Chagas ' disease depresses the delayed hypersensitivity immune response directly.