Carbon monoxide, autophagy and cytoprotection in response to cerebral ischemia

Dissertação para obtenção do Grau de Mestre em Genética Molecular e Biomedicina

Antibody response to Salmonella typhi lw human Schistosomiasis mansoni

Antibody response to Salmonella typhi O and H antigens was evaluated in 24 individuals with either hepatointestinal or hepatosplenic schistosomiasis mansoni before and after typhoid vaccination, and compared with that of non-infected controls. Before vaccination, Schistosoma-infected patients showed a higher frequency of positive antibody to O antigen and the same frequency to H antigen when compared with that of healthy individuals. However, those with hepatosplenic schistosomiasis showed higher titres of antibody to H antigen than those with hepatointestinal disease or healthy individuals. Infected subjects, particularly those with hepatointestinal disease, showed a decreased response after typhoid vaccine. Tins diminished ability to mount an immune response towards typhoid antigens dining schistosomiasis may interfere ivith the clearance of the bacteria from blood stream and, therefore, play a role in the prolonged survival of salmonella as obsewed in some patients with chronic salmonellosis associated with schistosomiasis.

Human immune response to triatomine embryo extract

Dipetalogaster maximus embryo extracts were used to stimulate peripheral blood mononuclear cells (PBMC) and in ELISA with sera either from Trypanosoma cruzi infected or non-infected individuals. The results showed that there was significant proliferative response and high antibody titers in sera of chagasic patients.

Modeling of integrated inductors for RF circuit design

Dissertação para obtenção do Grau de Mestre em Engenharia Electrotécnica

Integrated approach to assess vulnerability of the Coastal Region of Bangladesh due to climate change

Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.

Predictors of an unsatisfactory response to pentavalent antimony in the treatment of American visceral leishmaniasis

Although treatment of visceral leishmaniasis with pentavalent antimony is usually successful, some patients require second-line drug therapy, most commonly with amphotericin B. To identify the clinical characteristics that predict an inadequate response to pentavalent antimony, a case-control study was undertaken in Teresina, Piaui, Brazil. Over a two-year period, there were 19 cases of VL in which the staff physicians of a hospital prescribed second-line therapy with amphotericin B after determining that treatment with pentavalent antimony had failed. The control group consisted of 97 patients that were successfully treated with pentavalent antimony. A chart review using univariate and multivariate analysis was performed. The cure rate was 90% with amphotericin B. The odds ratio for the prescription of amphotericin B was 10.2 for children less than one year old, compared with individuals aged over 10 years. Patients who presented coinfection had an OR of 7.1 while those on antibiotics had an OR of 2.8. These data support either undertaking a longer course of therapy with pentavalent antimony for children or using amphotericin B as a first-line agent for children and individuals with coinfections. It also suggests that chemoprophylaxis directed toward bacterial coinfection in small children with VL may be indicated.

Trypanosoma cruzi in marsupial didelphids (Philander frenata and Didelhis marsupialis): differences in the humoral immune response in natural and experimental infections

Philander frenata and Didelphis marsupialis harbor parasitism by Trypanosoma cruzi without developing any apparent disease and on the contrary to D. marsupialis, P. frenata maintains parasitism by T. cruzi II subpopulations. Here we compared the humoral immune response of the two didelphids naturally and experimentally infected with T. cruzi II group, employing SDS-PAGE/Western blot techniques and by an Indirect immunofluorescence assay. We also studied the histopathological pattern of naturally and experimentally infected P. frenata with T. cruzi. P. frenata sera recognized more antigens than D. marsupialis, and the recognition pattern did not show any change over the course of the follow up of both didelphid species. Polypeptides of 66 and 90kDa were the most prominent antigens recognized by both species in the soluble and enriched membrane fractions. P. frenata recognized intensely also a 45kDa antigen. Our findings indicate that: 1) there were no quantitative or qualitative differences in the patent or subpatent phases in the recognition pattern of P. frenata; 2) the significant differences in the recognition pattern of parasitic antigens by P. frenata and D. marsupialis sera suggest that they probably "learned" to live in harmony with T. cruzi by different strategies; 3) although P. frenata do not display apparent disease, tissular lesions tended to be more severe than has been described in D. marsupialis; and 4) Both didelphids probably acquired infection by T. cruzi after their evolutionary divergence.

Integrated functional genomics for improved manufacture of recombinant enveloped virus

Dissertation presented to obtain the Ph.D degree in Engineering and Technology Sciences-Biotechnology

Regulation of gene expression by SnRK1 kinases and miRNAs during the plant stress response

Dissertation presented to obtain the Ph.D degree in Plant Physiology

Evaluation of the immune response to CRA and FRA recombinant antigens of Trypanosoma cruzi in C57BL/6 mice

Humoral and cellular immune responses were evaluated in 44 C57BL/6 mice immunized with the Trypanosoma cruzi recombinant antigens CRA and FRA. Both antigens induced cutaneous immediate-type hypersensitivity response. The levels of IgG1, IgG2a, IgG2b and IgG3 were high in CRA immunized mice. IgG3 was the predominant isotype. Although no difference in antibody levels was observed in FRA-immunized mice when compared to control mice, both antigens were able to induce lymphoproliferation in immunized mice. Significant differences were observed between incorporation of [³H]- thymidine by spleen cell stimulated in vitro with CRA or FRA and the control group. These results suggest that CRA and FRA could be involved in mechanisms of resistance to Trypanosoma cruzi infection.

Response to chemotherapy with benznidazole of clones isolated from the 21SF strain of Trypanosoma cruzi (biodeme Type II, Trypanosoma cruzi II)

Susceptibility to chemotherapy with benznidazole was investigated of 5 clones isolated from the 21 SF strain (biodeme Type II, Trypanosoma cruzi II). Swiss mice were infected with the parental strain for each clone and submitted to chemotherapy with benznidazole (100mg/kg/day during 90 days). Treatment determined negativity of the parasitemia. Cure rates were evaluated by parasitological cure tests. Serology was evaluated for treated animals (titers from negative to 1:640) and untreated controls (1:160 to 1:640). Cure rates varied from 30 to 100% for the 5 clones, and were 25% for the parental strain. Results suggested that the variability of response to treatment of the clonal populations of Trypanosoma cruzi II strains is responsible for the high variation in the response to chemotherapy with benznidazole and nifurtimox by strains of this biodeme.

The role of integrated home-based care in patient adherence to antiretroviral therapy

Non-adherence is one of the primary obstacles to successful antiretroviral therapy in HIV+ patients worldwide. In Brazil, the Domiciliary Therapeutic Assistance is a multidisciplinary and integrated home-based assistance program provided for HIV+ patients confined in their homes due to physical deficiency. This study investigated ADT's ability to monitor and promote appropriate adherence to ARV therapy. Fifty-six individuals were recruited from three study groups: Group 1 - patients currently in the ADT program, Group 2 - 21 patients previously treated by the ADT program, and Group 3 - 20 patients who have always been treated using conventional ambulatory care. Using multivariable self-reporting to evaluate adherence, patients in the ADT program had significantly better adherence than patients in ambulatory care (F = 6.66, p = 0.003). This effect was independent of demographic and socioeconomic characteristics as well as medical history. Patients in the ADT program also showed a trend towards greater therapeutic success than ambulatory patients. These results suggest the incorporation of characteristics of ADT in conventional ambulatory care as a strategy to increase adherence to ARV therapy.

DNA-Protein interaction: a response regulatory protein associated with Mo homeostasis in Desulfovibrio alaskensis G20.

Dissertation for a degree in Doctor in Sustainable Chemistry