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J C Bina

Publications and source records attributed to J C Bina.

At least 19 recordsLinked to original sources
PubMed1999

[High intensity signal in basal ganglia on T1 weighted images: case report in Manson's Schistosomiasis with portal systemic encephalopathy].

We report a case of mansonic schistosomiasis with portal systemic encephalopathy associated with a high intensity signal in basal ganglia on TI weighted images due to deposition of manganese in tissues related with portal-systemic collateral vessels. A bibliographic review was done focusing the magnetic resonance findings. To the best of our knowledge, these signal changes have not yet been associated with Manson's schistosomiasis.

Adult↗
PubMed1993

Correlation between cell-mediated immunity and degree of infection in subjects living in an endemic area of schistosomiasis.

Cell-mediated immunity to Schistosoma mansoni antigens, unrelated antigens and mitogens was evaluated in 50 subjects with the same degree of exposure to infection living in an endemic area of schistosomiasis. The degree of infection, assessed by the number of eggs/g of stool, was variable in this population (0-5604), suggesting differences in susceptibility to infection. Absence of lymphoproliferative response was observed in 56% of this group, despite having a response to purified protein derivative of tuberculin (PPD) and tetanus toxoid (TT) antigens and to pokeweed mitogen. The 50 subjects were divided into two groups, according to their degree of infection. The lymphoproliferative responses to schistosomula and adult worm antigens in the group with a low degree of infection (< 400 eggs/g of stool) were higher than the ones documented in patients with a high degree of infection (> 400 eggs/g of stool), and these differences were statistically significant (p < 0.001). An inverse correlation between the lymphocyte proliferation in response to S. mansoni antigens and the degree of infection was also observed (p = 0.02), indicating that subjects with a lower degree of infection have a higher lymphoproliferative response to schistosomula and adult worm antigens. No differences in the lymphocyte reactivity to other antigens (PPD and TT) were detected in these groups. An impairment of interferon-gamma in vitro production was observed when the lymphocytes from these subjects were stimulated with S. mansoni adult worm antigen, although they produced gamma interferon in response to phytohemagglutinin.

Adolescent↗
PubMed1993

Characteristics of the acquired immunodeficiency syndrome in Brazil.

The clinical and epidemiologic characteristics of the acquired immunodeficiency syndrome (AIDS) were studied in a tropical area of Brazil. During an 18-month period (July 1989-January 1991), 111 consecutive AIDS patients (102 men and nine women) were evaluated. Patients reported homosexual/bisexual activities (60%), intravenous drug use (19%), or both (6%), heterosexual activities (11%), blood transfusions (2%), and 2% belonged to an undetermined category. Weight loss, fever, oral thrush, and diarrhea were present in > or = 70% of the patients at presentation. An unexpected high frequency of hepatomegaly (49%) was detected, and found to be significantly associated with tuberculosis (P < 0.0001). Although the epidemiologic features of human immunodeficiency virus transmission were comparable to the United States/European pattern, the clinical spectrum of opportunistic infections more closely resembled that reported in Africa and Haiti, with a greater frequency of fungal and mycobacterial infections than Pneumocystis carinii pneumonia and viral infections.

AIDS-Related Opportunistic Infections↗
PubMed1992

[Specific treatment as a weapon for controlling schistosomiasis].

The specific treatment of schistosomiasis has been thought to prevent or revert severe forms of the disease, since 1957. Starting in 1977, prospective and controlled studies performed in different endemic areas of Brazil were able to confirm such facts. The new drugs, of high efficacy and well tolerated--Oxamniquine and Praziquantel--can actually prevent and cure the severe forms of some patients, contributing to change the morbidity pattern of the disease, thus being considered as important weapons in its control. Analysis of the principal Brazilian articles on the subject is presented.

Adolescent↗
PubMed1988

Human resistance to Schistosoma mansoni is associated with IgG reactivity to a 37-kDa larval surface antigen.

The aim of this work was to determine whether human resistance to Schistosoma mansoni was associated with increased antibody reactivity to certain larval surface Ag. To this end, young residents of a hyperendemic area were selected for their low or high susceptibility to reinfection after parasitologic cure, and the reactivity of their sera to individual larval surface Ag was determined at different times before and after treatment. The data showed that six Ag: 202, 165, 90 to 92, 85, 72, and 37 kDa are the principal targets on the larva of IgG in the sera of resistant subjects. The comparative study, by immunoblotting and ELISA on purified Ag, of the sera from high and low susceptibility subjects indicates that IgG reactivity toward the 37-kDa Ag may be associated with resistance. This work and ongoing vaccination trials carried out in mice suggest that the 37-kDa Ag may have vaccinating potentials.

Adolescent↗
PubMed1986

Enhancement of human eosinophil cytotoxicity and leukotriene synthesis by biosynthetic (recombinant) granulocyte-macrophage colony-stimulating factor.

Culture medium conditioned by activated human T lymphocytes enhances the in vitro cytotoxicity of purified human eosinophils toward Schistosoma mansoni larvae, suggesting the existence of a mechanism for T lymphocyte regulation of eosinophil function. Here we show that purified biosynthetic (recombinant) human T lymphocyte granulocyte-macrophage colony-stimulating factor (GM-CSF) enhanced markedly two eosinophil functions: cytotoxicity toward schistosomula by a mean of 676%, and calcium ionophore A23187-induced generation of leukotriene C4 (LTC4) by a mean of 135%. Augmentation of each eosinophil function by GM-CSF was time- and dose-dependent, with a dose-response relationship at concentrations between 1 and 20 pM. Tumor necrosis factor (TNF) enhanced eosinophil cytotoxicity with slower kinetics, a different dose-dependence relationship, and to a lower maximum, as compared with GM-CSF. There was no detectable effect of TNF on calcium ionophore A23187-induced generation of LTC4. The effect of GM-CSF on arachidonic acid metabolism to LTC4 reached a plateau with 60 min of incubation before stimulation with ionophore, and was characterized by an initial augmentation of the intracellular level of LTC4 and a subsequent increment in extracellular LTC4. Thus, GM-CSF can serve as a mediator for T lymphocyte regulation of functions of mature eosinophils. It is also the first defined macromolecule known to enhance metabolism of membrane-derived arachidonic acid via the 5-lipoxygenase pathway.

Calcimycin↗
PubMed1984

Modulation of eosinophil cytotoxicity by blood mononuclear cells from healthy subjects and patients with chronic schistosomiasis mansoni.

Human blood mononuclear cells in culture release a factor(s) that markedly enhances eosinophil cytotoxicity. This factor(s) stimulates eosinophils to kill Schistosoma mansoni larvae at low antibody concentrations and cell/target ratios. A study of the mononuclear cells of 78 subjects with chronic schistosomiasis mansoni and 33 controls suggests that the production of eosinophil cytotoxicity enhancing activity (ECEA) is suppressed in most patients with S. mansoni infections. Suppression of ECEA production was not observed, however, with cells from many patients with heavy infections, including patients with hepatosplenomegaly. The possible role of ECEA in the development of pathology is discussed.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1982

Titres of antibodies to gut-derived antigens in patients with chronic schistosomiasis mansoni.

Serum titres of antibodies against six intestinal, one ubiquitous and one non-intestinal bacteria were determined in patients with severe hepatosplenic schistosomiasis mansoni, with light intestinal schistosomiasis and in normal subjects. No significant difference was observed among the three groups of subjects for levels of antibodies against two non-intestinal bacteria and four of the intestinal bacteria. Patients with hepatosplenic schistosomiasis had titres of antibodies against one strain of Pseudomonas aeruginosa and one strain of Escherichia coli lower than those observed in other groups of subjects. Despite the partial obliteration of the hepatic blood outflow and the elevated portal pressure, hepatic clearance of the portal blood is efficient in chronic human schistosomiasis, and unlike alcoholic liver cirrhosis, avoids excessive stimulation of the immune system by a gut-derived antigens.

Antibodies↗
PubMed1981

Correlation of circulating immune complexes and complement breakdown products with the severity of the disease in human schistosomiasis mansoni.

Circulating immune complexes and complements compounds were measured in serum and plasma from 66 patients with three different clinical forms of chronic schistosomiasis mansoni: intestinal, hepato-intestinal and hepatosplenic. Three different methods were used: the 125I-C1q-binding assay, conglutinin-binding assay (KgB) and Raji cell-binding assay. Approximately 25% of the patients were positive for circulating immune complexes as measured by the C1q and Raji assays. The levels of complexes increased significantly with the severity of the disease. 60% of the patients were positive for immune complexes as measured by the KgB-assay but the incidence of positive results was not clearly influenced by the stage of the disease. There was no significant correlation between immunoglobulin levels and immune complexes. The complement profile of these patients does not suggest a dramatic activation of the complement system. However, there was a progressive decrease in the plasma levels of C4 and an increase of C3d levels which correlated significantly with the severity of the disease.

Adolescent↗
PubMed1980

Enhanced helminthotoxic capacity of eosinophils from patients with eosinophilia.

To determine whether eosinophils from patients with eosinophilia have an enhanced capacity to kill parasites, we compared purified eosinophils (mean purity, 89 per cent) from 30 patients with various degrees of eosinophilia and with or without infection with Schistosoma mansoni for the capacity to kill schistosomula, the larval stage of S. mansoni, in vitro. There was a significant correlation between peripheral eosinophil count and antibody-dependent, eosinophil-mediated death of parasites after 40 hours of culture (P < 0.0001). Antibody-dependent adherence of eosinophils, measured after two hours of incubation, also correlated with the capacity of the eosinophils to kill the parasites. The correlation between the killing capacity of eosinophils and their peripheral-blood count was observed in patients both with and without S. mansoni infection. We suggest that eosinophilia involves not only a quantitative change in eosinophil numbers but also a qualitative change in functional capacity that renders circulating eosinophils more effective in resisting parasitic infections.

Antibodies↗
PubMed1977

Mother-child relationship in human schistosomiasis mansoni. I. Parasitic antigens and antibodies in milk.

Immunoglobulins, anti-Schistosoma mansoni antibodies, complement components and schistosome antigens were investigated in milk from mothers infected with S. mansoni. No significant differences of immunoglobulins or complement component levels were observed between infected and control mothers. Anti-S. mansoni antibodies were detected in the milk of 8 out of 25 infected mothers. A significant relationship was observed between serum and "4", were demonstrated in milk from infected patients by the double diffusion micromethod. The function of these immunologically active substances transmitted by milk from mother to child is discussed.

Antibodies↗
PubMed1977

Immunological studies in human schistosomiasis. III. Immunoglobulin levels, antibodies, and delayed hypersensitivity.

Levels of IgG, IgE, IgM, and IgA were determined, specific antibodies were detected by the fluorescent antibody test, hemagglutination test, complement fixation test and immunoelectrophoresis, and intradermal tests for delayed hypersensitivity to Schistosoma mansoni antigens were performed in Brazilian patients with schistosomiasis mansoni. The results were compared according to the clinical forms of the disease. IgG levels and antibody titers increased progressively in the subclinical, hepatomegalic, and hepatosplenic forms and there was a statistical relationship between IgG levels and the intensity of responses to the four serological tests; Delayed hypersensitivity (DHS) was found more frequently in hepatosplenic patients and more particularly in those with splenomegaly. DHS also correlated with age, but not with sex or with skin color. The strongest DHS reactions were observed in patients 20 to 34 years old, and in those having the highest fecal egg output. IgG levels, antibody titers, and DHS responses decreased after splenectomy and portal filtration of the worms. No significant variation was observed between untreated subjects, patients who were splenectomized and a group not subject to reinfection for 4 yearsk0

Antibodies↗
PubMed1977

Circulating immune complexes in schistosomiasis.

Circulating immune complexes (CIC) were investigated by the [125I]Clq binding test, the complement fixation test (CFT) and optical density measurement after redissolving 3% polyethylene glycol precipitates of serum from patients infected by Schistosoma mansoni. A highly significant correlation was obtained among these three techniques. More than 60% of the patients demonstrated significantly higher values than control individuals. The level of CIC was found to be higher in the mild than in the hepatosplenic form of the disease. Parasite antigen, IgG, IgM and IgE were characterized in these CIC. In experimental schistosomiasis in mice, maximum levels of CIC, evaluated by the CFT, were observed between the 40th and the 70th day of infection.

Animals↗
PubMed1976

Sensitization to Schistosoma mansoni antigen in uninfected children born to infected mothers.

Sensitization to Schistosoma mansoni antigen in uninfected children born to infected or uninfected mothers was studied by intradermal reaction. Immediate skin reaction, Arthus phenomenon, and delayed skin responses were noted. The skin response at 24 hr was positive in 48.1% of the uninfected children born to infected mothers, and in only 7.5% of uninfected (control) children born to uninfected mothers. Areas of skin reactions were also larger in the group born to infected mothers. Both of these differences were statistically significant. There were no significant variations according to age or sex. Only one immediate skin reaction was noted in each group, and Arthus phenomenon was never observed.

Antigens↗