Building the genomic nation: ‘Homo Brasilis’ and the ‘Genoma Mexicano’ in comparative cultural perspective

This article explores the relationship between genetic research, nationalism and the construction of collective social identities in Latin America. It makes a comparative analysis of two research projects – the ‘Genoma Mexicano’ and the ‘Homo Brasilis’ – both of which sought to establish national and genetic profiles. Both have reproduced and strengthened the idea of their respective nations of focus, incorporating biological elements into debates on social identities. Also, both have placed the unifying figure of the mestizo/mestiço at the heart of national identity constructions, and in so doing have displaced alternative identity categories, such as those based on race. However, having been developed in different national contexts, these projects have had distinct scientific and social trajectories: in Mexico, the genomic mestizo is mobilized mainly in relation to health, while in Brazil the key arena is that of race. We show the importance of the nation as a frame for mobilizing genetic data in public policy debates, and demonstrate how race comes in and out of focus in different Latin American national contexts of genomic research, while never completely disappearing

Vaccination with Recombinant Microneme Proteins Confers Protection against Experimental Toxoplasmosis in Mice

Toxoplasmosis, a zoonotic disease caused by Toxoplasma gondii, is an important public health problem and veterinary concern. Although there is no vaccine for human toxoplasmosis, many attempts have been made to develop one. Promising vaccine candidates utilize proteins, or their genes, from microneme organelle of T. gondii that are involved in the initial stages of host cell invasion by the parasite. In the present study, we used different recombinant microneme proteins (TgMIC1, TgMIC4, or TgMIC6) or combinations of these proteins (TgMIC1-4 and TgMIC1-4-6) to evaluate the immune response and protection against experimental toxoplasmosis in C57BL/6 mice. Vaccination with recombinant TgMIC1, TgMIC4, or TgMIC6 alone conferred partial protection, as demonstrated by reduced brain cyst burden and mortality rates after challenge. Immunization with TgMIC1-4 or TgMIC1-4-6 vaccines provided the most effective protection, since 70% and 80% of mice, respectively, survived to the acute phase of infection. In addition, these vaccinated mice, in comparison to non-vaccinated ones, showed reduced parasite burden by 59% and 68%, respectively. The protective effect was related to the cellular and humoral immune responses induced by vaccination and included the release of Th1 cytokines IFN-γ and IL-12, antigen-stimulated spleen cell proliferation, and production of antigen-specific serum antibodies. Our results demonstrate that microneme proteins are potential vaccines against T. gondii, since their inoculation prevents or decreases the deleterious effects of the infection

A Recombinant Human Anti-Platelet scFv Antibody Produced in Pichia pastoris for Atheroma Targeting

Cells of the innate and adaptive immune system are key factors in the progression of athero-sclerotic plaque, leading to plaque instability and rupture, potentially resulting in acute ather-othrombotic events such as coronary artery disease, cerebrovascular disease and peripheral arterial disease. Here, we describe the cloning, expression, purification, and immunoreactivity assessment of a recombinant single-chain variable fragment (scFv) derived from a human anti-αIIbβ3 antibody (HuAb) selected to target atheromatous lesions for the presence of platelets. Indeed, platelets within atheroma plaques have been shown to play a role in inflammation, in platelet-leucocyte aggregates and in thrombi formation and might thus be considered relevant biomarkers of atherosclerotic progression. The DNA sequence that encodes the anti-αIIbβ3 TEG4 scFv previously obtained from a phage-display selection on activated platelets, was inserted into the eukaryote vector (pPICZαA) in fusion with a tag sequence encoding 2 cysteines useable for specific probes grafting experiments. The recombinant protein was expressed at high yields in Pichia pastoris (30 mg/L culture). The advantage of P. pastoris as an expression system is the production and secretion of recombinant proteins in the supernatant, ruling out the difficulties encountered when scFv are produced in the cytoplasm of bacteria (low yield, low solubility and reduced affinity). The improved conditions allowed for the recovery of highly purified and biologically active scFv fragments ready to be grafted in a site-directed way to nanoparticles for the imaging of atherosclerotic plaques involving inflammatory processes and thus at high risk of instability

Cárie dentária e flúor: uma relação do século XX Dental caries and fluorine: a twentieth century relation

No início do século XX a cárie dentária era um problema de saúde pública, na maior parte do planeta. As populações conviviam com infecção, dor, sofrimento e mutilação. A descoberta do efeito preventivo do flúor o transformou, ao longo do século, no principal agente utilizado no enfrentamento da doença em todo o mundo. Em vários países e também no Brasil produtos fluorados têm sido apontados como os principais responsáveis pelo declínio observado na prevalência da cárie. No Brasil, estudos pioneiros realizados nos anos 50 e 60 corroboraram a eficácia preventiva da fluoretação das águas. No período 1986-1996, com 42% da população recebendo água fluoretada, a queda na prevalência da cárie entre crianças de 12 anos de idade foi de 53%. Além da água fluoretada também os dentifrícios são, no presente, amplamente utilizados como veículos para uso do flúor em saúde pública. Neste artigo são abordados aspectos históricos do emprego de flúor, algumas características epidemiológicas da cárie dentária no Brasil, e as perspectivas da continuidade do uso de produtos fluorados nas próximas décadas.<br>In the early of Twentieth Century, dental caries were a big public health problem around world. Infection, pain, suffering and mutilation reached all people. The discovering of preventive effect of fluorine became them, through the Century, the main agent in fighting to disease worldwide. In various countries, including Brazil, fluoridated products have been pointed as main causes for dental caries prevalence decline. Also in Brazil, at the 50s and 60s, the preventive effect of water fluoridation was ratified for some pioneer studies. For the period 1986-1996 epidemiological data shown a significant reduction of 53% in the DMF-T index value at 12-years-old schoolchildren. Water and dentifrices are largely used as vehicle for fluoride in public health actions. In Brazil 42% of population has access to fluoridated water. Most dentifrices contain fluoride. This paper approach historical aspects of fluoride uses in public health and presents any epidemiological data on dental caries prevalence in Brazil. Conclude asking if fluoridated products will have same importance for oral health promotion in next decades