SIDCER informed consent form: principles and a developmental guideline.

The quality of informed consent forms (ICFs) remains an issue in clinical research. The lengthy and complicated ICFs currently being used lower research participants’ ability to read and understand the information provided therein. In collaboration with the Strategic Initiative for Developing Capacity in Ethical Review (SIDCER), we have developed the SIDCER ICF, which could be of value in improving the quality of the ICFs. The three principles underlying the SIDCER ICF were: (i) an ICF contains all the required regulatory elements; (ii) an ICF provides only such information as is relevant for the subject’s decision-making; and (iii) an ICF presents information in a simple format that conveys relevant information to the target population. The SIDCER ICF template, with its instructions, was then structured to assist an investigator in developing an enhanced ICF according to the three principles. The applicability of the SIDCER ICF was tested using a phase I study protocol, and a variety of experts with a special interest in ethics and clinical research were invited to evaluate the comprehensiveness of the three-page ICF for the phase I study. The SIDCER ICF template was refined and finalised in accordance with the results and comments from the experts.

Identification of HLA-A24 restricted pre-erythrocytic stage specific T-cell epitopes using Plasmodium falciparum synthetic peptides: a preliminary study.

Fourteen (9 amino acids) peptides of Plasmodium falciparum pre-erythrocytic stage antigens, namely, TRAP, CTRP, LSA-1, STARP and MSP-1, restricted to HLA-A24 and specific to T-cell response were identified. The antigen-specific IFN-gamma responses of these synthetic peptides in malaria exposed and non-malaria exposed healthy adult volunteers were detected using the ex vivo ELISPOT assay. Five peptides from TRAP and CTRP antigens significantly increased IFN-y responses of 1/9 in malaria-exposed volunteers. There is no statistically significant difference in positive T-cell response induced by any peptides in malaria exposed volunteers when evaluated as a group. The frequency of expressed HLA-A24 in malaria-exposed and non-malaria-exposed healthy adults living in northwest and central Thailand was 90% (27/30) and 100% (12/12), respectively. Although no association between positive T-cell response and HLA-A24 was found, due to the low number of positive responders achieved, one positive responder in malaria- exposed group was presented as HLA-24.

Blood transfusion and iatrogenic risks in Mexico city: anti-Trypanosoma cruzi seroprevalence in 43,048 blood donors, evaluation of parasitemia, and electrocardiogram findings in seropositive

Iatrogenous transmission of Trypanosoma cruziby blood transfusion was suggested as a potential risk by Pellegrino (1949). Seropositive blood donors in Mexico were first reported in 1978, however, limited information is available due to small sampling, the use of heterogeneous serologic assays, and geographically limited studies. A wide survey carried out in 18 out of the 32 states of Mexico, showed a national mean of 1.6 percent seropositive among 64,969 donors, ranging from 0.2 to 2.8 percent. In the present study, we have screened 43,048 voluntary blood donors in a period of five years at the Instituto Nacional de Cardiología I. Chávez, a concentration hospital located in Mexico city which serves mainly the metropolitan area and accepts from all over the country. Standardized ELISA and IIF were used to identify seropositive individuals in addition to hemoculture, PCR and standard 12 lead ECG tests that were applied to a group of seropositive patients (29/161). The result showed a seropositivity of 0.37 percent (161/43,048). From the group of seropositive individuals 40 percent (12/29) were potential carriers of T. cruzi at the donation time and 5/29 had subclinical ECG abnormalities. Parasitological tests performed in 70 erythrocyte and platelet fractions from seropositive units (70/161) showed negative results. Our findings strongly support T. cruzi screening in the transfusion medicine practice and identify subclinical heart disease among seropositive blood donors.

Electrocardiographic findings in Mexican chagasic subjects living in high and low endemic regions of Trypanosoma cruzi infection

In México the first human chronic chagasic case was recognized in 1940. In spite of an increasing number of cases detected since that time, Chagas disease in México has been poorly documented. In the present work we studied 617 volunteers subjects living in high and low endemic regions of Trypanosoma cruzi infection with seroprevalence of 22 percent and 4 percent respectively. Hemoculture performed in those seropositive subjects failed to demonstrate circulating parasites, however polymerase chain reaction identified up to 60 percent of them as positives. A higher level of anti-T. cruzi antibodies was observed in seropositive residents in high endemic region, in spite of similar parasite persistence (p < 0.05). On standard 12 leads electrocardiogram (ECG) 20 percent to 22 percent seropositive individuals from either region showed right bundle branch block or ventricular extrasystoles which were more prevalent in seropositive than in seronegative individuals (p < 0.05). In conclusion, the frequency or type of ECG abnormality was influenced by serologic status but not by endemicity or parasite persistence. Furthermore, Mexican indeterminate patients have a similar ECG pattern to those reported in South America