Analysis of antidiarrhoeic effect of plants used in popular medicine

People customarily use the extracts of plants known to have antidiarrhoeal effects without any scientific base to explain the action of the extract. For this reason, an investigation was undertaken with a view to determining the efficacy of the effects of the brute aqueous extract (BAE) of the leaves of Psidium guajava (guava), Stachytarpheta cayenensis (bastard vervain), Polygonum punctatum (water. smartweed), Eugenia uniflora (Brazil or Surinam cherry) and Aster squamatus (zé-da-silva) on the intestinal transport of water in rats and on the gastrointestinal propulsion in mice. With the exception of the BAE of S. cayenensis, all other BAE's have increased the absorption of water in one or more intestinal portion in relation to the control group. All tested BAE, except that of P. punctatum, reduced the gastrointestinal propulsion in relation to that of the control group. The results indicate that the BAE of the leaves of P. guajava, S. cayenensis, P. punctatum, E. uniflora and A. squamatus have a potential antidiarrhoeic effect to be confirmed by additional investigations in animals infected with enteropathogenic agents.

Avaliação da proteção conferida pela via de sinalização do Nrf2 num modelo experimental de sobrecarga de ferro in vivo

O ferro é encontrado em praticamente todos os seres vivos, sendo um cofator para proteínas que desempenham funções essenciais à vida. Nos mamíferos, a maioria do ferro está incorporada na hemoglobina ou armazenado no fígado, ligado à ferritina. É absorvido pelos enterócitos, sendo a principal forma de controlo dos seus níveis. A sobrecarga de ferro pode levar a hemocromatose, podendo ser tóxica para vários órgãos. O fator de transcrição Nrf2 é importante na ativação de genes citoprotetores em situações de stress oxidativo/eletrofílico, colocando-se a hipótese de que poderá estar envolvido na resposta à progressão de doença devido à sobrecarga de ferro. Com o objetivo de determinar se a via do Nrf2 representa uma proteção contra a toxicidade do ferro a nível hepático, foram realizadas duas experiências nas quais murganhos C57BL/6 (B6) e Nrf2-/- machos foram alimentados com dieta standard ou com dieta enriquecida em ferro carbonilo (FeC) (0,5% ou 2,0%). Os resultados demonstram sobrecarga de ferro nos animais que receberam dieta enriquecida, sendo que os que receberam FeC 2,0% apresentaram níveis mais elevados de ferro hepático e sérico, bem como da saturação da transferrina. Os murganhos Nrf2-/- são mais suscetíveis a esta acumulação, mostrando evidências patológicas mais graves, nomeadamente necrose hepatocítica e infiltração de células inflamatórias. A deleção do Nrf2 associado a uma dieta suplementada com FeC 2,0% parece não ser suficiente para o desenvolvimento de fibrose hepática. O estudo da expressão de genes e proteínas do metabolismo do ferro mostrou que os animais B6 e Nrf2-/- são igualmente capazes de responder à sobrecarga de ferro, sugerindo que a sua diferente suscetibilidade à toxicidade do ferro não se deverá a uma regulação ineficiente da homeostasia do Fe. A dieta com FeC 2,0% aumentou a expressão de dois genes alvo do Nrf2, Nqo1 e Gsta1, o que não se verificou com os genes e proteínas GCLC e GCLM. A expressão de genes pró-inflamatórios não mostrou evidências de inflamação nestes animais. Foi demonstrado que os animais Nrf2-/- são mais suscetíveis à toxicidade do ferro, concluindo-se que a via do Nrf2 é ativada em resposta a uma dieta contendo quantidades excessivas de FeC e que confere proteção contra a acumulação de ferro em murganhos B6.

In vivo and in vitro effects of RAD001 on bladder cancer

Objective: To evaluate the influence of Everolimus (RAD001) on chemically induced urothelial lesions in mice and its influence on in vitro human bladder cancer cell lines. Methods: ICR male mice were given N-butyl-N-(4-hydroxybutyl) nitrosamine in drinking water for a period of 12 weeks. Subsequently, RAD001 was administered via oral gavage, for 6 weeks. At the end of the experiment, all the animals were sacrificed and tumor development was determined by means of histopathologic evaluation; mammalian target of rapamycin (mTOR) expressivity was evaluated by immunohistochemistry. Three human bladder cancer cell lines (T24, HT1376, and 5637) were treated using a range of RAD001 concentrations. MTT assay, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), and flow cytometry were used to assess cell proliferation, apoptosis index, and cell cycle analysis, respectively. Immunoblotting analysis of 3 cell line extracts using mTOR and Akt antibodies was performed in order to study the expression of Akt and mTOR proteins and their phosphorylated forms. Results: The incidence of urothelial lesions in animals treated with RAD001 was similar to those animals not treated. RAD001 did not block T24 and HT1376 cell proliferation or induce apoptosis. A reduction in cell proliferation rate and therefore G0/G1 phase arrest, as well as a statistically significant induction of apoptosis (P 0.001), was only observed in the 5637 cell line. Conclusion: RAD001 seems not to have a significant effect on chemically induced murine bladder tumors. The effect of RAD001 on tumor proliferation and apoptosis was achieved only in superficial derived bladder cancer cell line, no effect was observed in invasive cell lines.

Immunoperoxidase technique in experimental chronic chagasic myocarditis

Chagas'disease has been described as the commonest form of chronic myocarditis. An immunologic pathogenesis has been discribed for this form of the disease. So far, no immunoperoxidase technique has been used for the detection of immunological deposits in chronic experimental Chagas'myocardiopathy. Forty-one Swiss mice, three months old were inoculated intraperitoneally with doses between 10 and 10(5) Tulahuen trypomastigotes. Mice were reinoculated one month after with doses between 10² and 10(5) and sacrificed at 6 (n=21) and 9 months (n=9) after the first inoculation. ECGs were recorded before sacrifice. Immunoperoxidase technique (peroxidase-antiperoxidase method), immunofluorescence (direct and indirect) as well as histological studies were performed in myocardiums and skeletal muscles of the surviving animals. The most sensitive methods for detecting chronic chagasic infection were the routine histologic studies (73%) and the ECGs 83% and 89% on 6 and 9 mo. post-infected mice, respectively. Myocardial involvement varied from interstitial mild focal lymphocyte infiltrates up to replacement of myocytes by loose connective tissue. Atrial myocardiums (21/23, 91%) were more affected than ventricles (9/23, 39%). Typical chagasic nests were rarely found. Skeletal muscle involvement (11/18 and 7/9) varied from mild to extensive lymphocyte and plasmacell infiltrates, and necrotic fibers. The involved antigen were shown in skeletal muscles by the immunoperoxidase technique as diffusely arranged granular intracytoplasmatic deposit for both IgC and total immunoglobulins. The coincidence between this technique and histologic muscle lesions was 11/18 (61(%) in 6 mo. and 6/8 (75%) at 9 mo. post-infection. In heart, delicate granular deposits of total immunoglobulins were seen diffusely arranged within the ventricular myocytes; coincidence between immunoperoxidase technique anl histologic involvement increased from 36 to 66% in animals sacrifeced 6 and 9 mo. post-infection. This strongly stressed the increase of immunologic phenomena with the chronification of infection. Concerning sensitivity, immunoperoxidase and direct immunofluorescence were highly sensitive in skeletal muscle (100%, p < 0.01). Conversely, direct immunofluorescence technique showed poor results in heart while immunoperoxidase increased its sensitivity from 21.4% (at 6 mo.) to 66.6% (at 9 mo.) post-infection (p < 0.001). Considering the necessity of obtaining an adequate vaccine in order to prevent this disease an experimental model like this, rendering immunological reactions as revealed by the immunoperoxidase technique, would be useful.

Neostigmine in the treatment of snake accidents caused by Micrurus frontalis: report of two cases

Antivenom in order to be effective in the treatment of coral snake accidents must be injected very soon after the bite owing to the rapid rate of absorption of the venom neurotoxins. As this is not always possible, other forms of treatment besides serotherapy must be employed to avoid asphyxia and death. Neostigmine and artificial respiration are used for this purpose. Neostigmine restores neuromuscular transmission if the venom-induced blockade results from a reversible interaction of its neurotoxins with the end-plate receptors. This is the mechanism of the neuromuscular blockade produced by the venom of M. frontalis snakes from centereastern and southern Brazil, and Argentine. Neostigmine is able, therefore, to antagonize the blockade, and has been shown to be very effective in the treatment of the experimental envenomation of dogs and monkeys. In the present communication, two cases of M. frontalis accidents treated with antivenom and neostigmine are reported. In both, neostigmine was successful in producing regression of the paralysis, confirming the effectiveness shown in the treatment of the poisoning induced in animals by M. frontalis venom.

Human enterovirus infection in stray dogs. Some aspects of interest to public health

To investigate the possible role of domestic animals as reservoirs of human enteroviruses, we studied 212 stray dogs captured in different areas of the municipality of São Paulo. The captured animals were divided into 19 groups of 10 to 20 dogs each; faeces of 126 of the 212 dogs were processed for enterovirus isolation. The following viruses were isolated from 12 dogs: poliovirus type 1 (2 dogs), poliovirus type 3 (1 dog), echovirus type 7 (8 dogs) and echovirus type 15 (1 dog). Of the 12 infected animals, four had specific homotypic neutralizing antibody titres > 16. All 212 animals were tested for the presence of neutralizing antibodies to human enteroviruses. The frequency of neutralizing antibodies present in titres of > 16 was 10.3%, 3,8% and 4.3% for vaccinal prototypes of polioviruses 1, 2 and 3 respectively; 1,9%, 1.4% and 1.5% for wild prototypes of the same viruses, 11.3% for echovirus 7, and 2.4% for echovirus 15. The proportion of dogs with neutralizing antibodies varied with the virus studied. Some indication of the susceptibility of dogs to infection with human enteroviruses was demonstrated, and the importance of this fact for the Plan for Global Eradication of the Wild Poliovirus is discussed.

INFLUENCE OF DIETARY PROTEIN CONTENT ON Trypanosoma cruzi INFECTION IN GERMFREE AND CONVENTIONAL MICE

Germfree (GF) and conventional (CV) mice were fed on diets containing 4.4, 13.2 or 26.4% of protein (weight/weight). CV mice fed on low protein diet did not gain weight during four weeks, whereas the protein deficient diet did not affect the growth of GF mice. After four weeks on these diets, the mice were inoculated with 5x103 trypomastigotes of Trypanosoma cruzi. The protein deficiency affected less the GF than the CV mice, according to the following parameters: weight gain, hemoglobin, plasma protein and albumin levels and water and protein contents of the carcass. Infection with T. cruzi produced a significant decrease in hemoglobin levels, red blood cell count, and water and protein contents in the carcass. This decrease was more pronounced in the GF mice. Histopathologically, there was no difference between the treatments in animals with the same microbiological status (GF or CV). However, the disease was more severe in the GF than in the CV mice.

Experimental dermatophytosis in hamsters inoculated with Trichophyton mentagrophytes in the cheek pouch

This study presents the results of T. mentagrophytes inoculation in the cheek pouch of the hamster, an immunologically privileged site. Forty two animals were used: 21 inoculated with 10(6) fungi in the cheek pouch (group 1) and 21 inoculated initially with 10(6) fungi in the foot pad and 15 days later in the cheek pouch, with the same amount of fungi (group 2). Animals were sacrificed at 20 hours, 3, 7, 14, 30, 60, and 120 days; samples from inoculated cheek pouch, and foot pads submitted to the foot pad test (FPT), were collected. Independent of group and time of evolution of infection, animals did not develop delayed hypersensitivity evaluated through the FPT. The pre-inoculation of fungi in the foot pad did not change the morphology of lesions induced in the cheek pouch. Therefore, in animals of group 1 and 2, the introduction of the fungus in the cheek pouch resulted in focal lesion composed of a sterile acute inflammatory infiltrate, with abscess formation that evolved to a macrophagic reaction, and later to resolution even in the absence of immune response detectable by FPT. Our results indicate that in spite of the important role of the immune response in the spontaneous regression of dermatophytosis, other factors are also an integral part in the defense against this fungal infection.

The "in vitro" antifungal activity evaluation of propolis G12 ethanol extract on Cryptococcus neoformans

Cryptococcosis is a worldwide disease caused by the etiological agent Cryptococcus neoformans. It affects mainly immunocompromised humans. It is relatively rare in animals only affecting those that have received prolonged antibiotic therapy. The propolis is a resin that can present several biological properties, including antibacterial, antifungal and antiviral activities. The standard strain C. neoformans ATTC 90112 was used to the antifungal evaluation. The tests were realized with propolis ethanol extract (PEE) G12 in concentrations from 0.1 to 1.6 mg mL-1. The evaluation of MIC and MFC were done according to DUARTE (2002)5. The inhibitory effect of PEE G12 on the fungal growing was seen at the concentration of 0.2 mg mL-1 and 1.6 mg mL-1 was considered a fungicidal one.

Nocardiosis: an overview and additional report of 28 cases in cattle and dogs

Phenotypic characteristics, antimicrobial susceptibility profile, and clinical-epidemiological features of 28 Nocardia strains isolated from 19 cases of bovine mastitis, eight cutaneous-subcutaneous lesions and one case of pneumonia in dogs were evaluated. Microbiological, biochemical, cytological and scanning electron microscopy methods were used in diagnosis. Nocardia asteroides type IV, Nocardia otitidiscaviarum,Nocardia nova (type III) and Nocardia farcinica (type V) were isolated from bovine milk, bronchial lavage and/or cutaneous-subcutaneous abscesses in dogs. Nocardial bovine mastitis was diagnosed predominantly in clinical cases, in dairy herds with poor environmental hygienic conditions between milking and inappropriate intramammary therapy. Canine nocardiosis was observed commonly in animals co-infected with distemper virus. Sulphamethoxazole-trimethoprim (92.8%), amikacin (92.8%) and ceftiofur (92.8%) were the most effective drugs in 28 isolates. Multiple drug resistance to three or more and five or more antimicrobials was observed in ten (35.7%) and three (10.7%) strains, respectively, predominantly with use of cloxaxillin, cefoperazone and ampicillin. The species (type) classification, clinical-epidemiological characteristics, diagnosis, multiple-drug resistance and public health considerations in Nocardia strains isolated from cattle and dogs in Brazil are discussed, with special reference to report of bovine mastitis by N. otitidiscaviarum by first time in Brazil and the similarity between Nocardia species isolated from human and animal origin.

Potential utility of hyperbaric oxygen therapy and propolis in enhancing the leishmanicidal activity of glucantime

In this study we investigated the efficacy of hyperbaric oxygen (HBO) therapy, alone or combined with the pentavalent antimonial glucantime on Leishmania amazonensis infection. In parallel, the effect of Brazilian red propolis gel (propain) alone or combined with glucantime on L. amazonensis infection was evaluated. The inhibition of the infection in macrophages treated with glucantime in combination with HBO exposition was greater than that of macrophages treated with glucantime alone or HBO alone. The susceptible mouse strain BALB/c infected in the shaved rump with L. amazonensis treated with glucantime and exposed to HBO showed: time points in the course of the disease in which lesions were smaller than those of mice treated with glucantime alone and revascularization of the skin in the lesion site; interferon-gamma (IFN-g) levels were not elevated in lymph node cells from these animals. Propain alone was not efficient against lesions, although less exudative lesions were observed in animals treated with propain alone or combined with glucantime. These results reveal the potential value of HBO and red propolis in combination with glucantime for treating cutaneous leishmaniasis and encourage further studies on the effect of more aggressive HBO, propolis and glucantime therapies on different mouse models of leishmaniasis.

Effects of vitamin C supplementation on acute phase Chagas disease in experimentally infected mice with Trypanosoma cruzi QM1 strain

The tissue changes that occur in Chagas disease are related to the degree of oxidative stress and antioxidant capacity of affected tissue. Studies with vitamin C supplementation did not develop oxidative damage caused by Chagas disease in the host, but other studies cite the use of peroxiredoxins ascorbate - dependent on T. cruzi to offer protection against immune reaction. Based on these propositions, thirty "Swiss" mice were infected with T. cruzi QM1 strain and treated with two different vitamin C doses in order to study the parasitemia evolution, histopathological changes and lipid peroxidation biomarkers during the acute phase of Chagas disease. The results showed that the parasite clearance was greater in animals fed with vitamin C overdose. There were no significant differences regarding the biomarkers of lipid peroxidation and inflammatory process or the increase of myocardium in animals treated with the recommended dosage. The largest amount of parasite growth towards the end of the acute phase suggests the benefit of high doses of vitamin C for trypomastigotes. The supplementation doesn't influence the production of free radicals or the number of amastigote nests in the acute phase of Chagas disease.

FUNGI ISOLATED FROM THE EXCRETA OF WILD BIRDS IN SCREENING CENTERS IN PELOTAS, RS, BRAZIL

The identification of the fungal species belonging to the healthy microflora in animals is a precondition for the recognition of pathological processes causing them. The aim of this study was to investigate the presence of potentially pathogenic fungi in the feces of wild birds collected in Screening Centers. Samples were collected from the feces of 50 cages with different species of birds. The samples were processed according to the modified method STAIB and the plates incubated at 32 °C for up to ten days with daily observation for detection of fungal growth. The isolation of the following species was observed: Malassezia pachydermatis, Candida albicans, C. famata, C. guilliermondii, C. sphaerica, C. globosa, C. catenulata, C. ciferri, C. intermedia, Cryptococcus laurentii, Trichosporon asahii, Geotrichum klebahnii, Aspergillus spp., A. niger and Penicillium spp. Knowing the character of some opportunistic fungi is important in identifying them, facilitating the adoption of preventive measures, such as proper cleaning of cages, since the accumulation of excreta may indicate a risk for both health professionals and centers for screening public health.

CANINE VISCERAL LEISHMANIASIS CASE INVESTIGATION IN THE JACARE REGION OF NITEROI, RIO DE JANEIRO, BRAZIL

SUMMARY American visceral leishmaniasis is a vector-borne zoonosis in expansion in Brazil. Dogs are the main urban reservoir. Departing from a case of canine visceral leishmaniasis (CVL) in Jacaré, Niterói, Rio de Janeiro State, an epidemiological canine and entomological study was performed to assess the extension of the disease at the location. Sample was collected around the case and the dogs identified by serological tests (rapid double platform immunochromatographic exams, immunoenzymatic assay/ELISA, indirect immunofluorescence/IFAT). The parasitological diagnosis was performed in animals positive in at least one of these tests. The entomological study was carried out by using light traps and manual collection. The associations between canine variables and outcome (ELISA and IFAT reagents) were assessed by the chi-square test and adjusted by multivariate logistic regression for those associations with p < 0.1 in the bivariate analysis. Seventeen cases of CVL were detected among 110 evaluated dogs (prevalence of 15.5%). Presence of ectoparasites (OR 6.5; 95% CI 1.1-37.4), animals with clinical signs (OR 9.5; 95% CI 1.2-76.6), and previous cases of CVL in the same house (OR 17.9; 95% CI 2.2-147.1) were associated with the outcome. Lutzomyia longipalpiswas not detected. Our results are indicative of an ongoing transmission in the area.

The FML (Fucose Mannose Ligand) of Leishmania donovani: a new tool in diagnosis, prognosis, transfusional control and vaccination against human kala-azar

The Fucose-Mannose Ligand (FML) of Leishmania donovani is a complex glycoproteic fraction. Its potential use as a tool for diagnosis of human visceral leishmaniasis was tested with human sera from Natal, Rio Grande do Norte, Brazil. The FML-ELISA test, showed 100% sensitivity and 96% specificity, identifying patients with overt kala-azar (p < 0.001, when compared to normal sera), and subjects with subclinical infection. More than 20% apparently healthy subjects with positive reaction to FML developed overt kala-azar during the following 10 months. In the screening of human blood donnors, a prevalence of 5% of sororeactive subjects was detected, attaining 17% in a single day. The GP36 glycoprotein of FHL is specifically reconized by human kala-azar sera. The immunoprotective effect of FML on experimental L. donovanii infection was tested in swiss albino mice. The protection scheemes included three weekly doses of FML, supplemented or not with saponin by the subcutaneous or intraperitoneal routes and challenge with 2x 10(7) amastigotes of Leishmania donovani. An enhancement of 80.0 % in antibody response (p<0.001) and reduction of 85.5 % parasite liver burden (p<0.001) was detected in animals immunized with FML saponin, unrespectivety of the immunization route.