APLICAÇÃO DE FOTOIRRADIAÇÃO SOLAR PARA TRATAMENTO DE EFLUENTES DE LATICÍNIOS

A indústria de laticínios gera grande volume de efluentes. Estudos têm avaliado novas tecnologias para o tratamento destes efluentes, com destaque para os Processos Oxidativos Avançados. O presente estudo teve como objetivo avaliar a redução de carga orgânica de efluentes lácteos utilizando um processo fotocatalítico heterogêneo com a construção de um reator fotocatalítico (TiO2/UVsolar). O reator foi montado em escala piloto para desenvolvimento dos testes preliminares e avaliação da efetividade do tratamento. Os efluentes foram avaliados nas formas: bruto (in natura) e tratado, exposto 2 horas à radiação solar com circulação do efluente sob a placa contendo TiO2. Foram avaliados as variáveis de pH, cor, turbidez, DBO e DQO. Os resultados revelaram que houve aumento nos parâmetros: pH, cor e turbidez do efluente tratado, no entanto, houve redução de 66,1% para a DBO e 66,5% para a DQO, indicando uma considerável diminuição de matéria orgânica no efluente. Porém, novos estudos deverão ser realizados com o objetivo de minimizar principalmente a cor e turbidez a fim de possibilitar melhoria no tratamento e possível utilização em escala industrial deste equipamento.Palavras-chave: Efluente lácteo; Matéria Orgânica; Fotoirradiação solar

Th17 cells in human disease

Our understanding of the role of T cells in human disease is undergoing revision as a result of the discovery of T-helper 17 (Th17) cells, a unique CD4 + T-cell subset characterized by production of interleukin-17 (IL-17). IL-17 is a highly inflammatory cytokine with robust effects on stromal cells in many tissues. Recent data in humans and mice suggest that Th17 cells play an important role in the pathogenesis of a diverse group of immune-mediated diseases, including psoriasis, rheumatoid arthritis, multiple sclerosis, inflammatory bowel disease, and asthma. Initial reports also propose a role for Th17 cells in tumorigenesis and transplant rejection. Important differences, as well as many similarities, are emerging when the biology of Th17 cells in the mouse is compared with corresponding phenomena in humans. As our understanding of human Th17 biology grows, the mechanisms underlying many diseases are becoming more apparent, resulting in a new appreciation for both previously known and more recently discovered cytokines, chemokines, and feedback mechanisms. Given the strong association between excessive Th17 activity and human disease, new therapeutic approaches targeting Th17 cells are highly promising, but the potential safety of such treatments may be limited by the role of these cells in normal host defenses against infection.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72455/1/j.1600-065X.2008.00628.x.pd

The All-Age Prevalence of Helicobacter pylori Infection and Potential Transmission Routes. A Population-Based Study

Background and aims: Previous research on H. pylori epidemiology has mostly focused on adult populations. We have aimed to study H. pylori prevalence in all age groups including children and adolescents and to identify potential routes of transmission. Methods: Subjects from all age groups (children 0–11 years, adolescents 12–17 years and adults ≥18 years of age), recruited from both an urban and a rural community in Northern Norway, were invited to provide stool samples for the diagnosis of H. pylori antigen and to fill in a questionnaire (adult and adolescents only) on gastrointestinal symptoms, lifestyle factors and biometric data. Results: A total of 1 624 (35.3%) of the invited subjects, including 173 (39.3%) of the children, 46 (19.2%) of the adolescents, and 1 416 (36.1%) of the adults, responded to the invitation. H. pylori infection was nearly undetectable (0.6%) among the children, whereas the prevalence increased from 20% in adolescents toward a peak of 45% in the highest age group. Univariate analyses of possible risk factors of H. pylori infection showed significant associations to private well water, the use of outhouse toilet, and having farm animals in childhood, but the associations waned in multivariate analyses. Conclusions: In our populations, with apparent high hygienic standards, the transmission of H. pylori infection may start not only in childhood, but also in adolescence, where potential transmission routes may be outdoor toilet use, private well water, and farm animals

The Special Relationship in the Development and Function of T Helper 17 and Regulatory T Cells.

T helper 17 (Th17) cells play an essential role in the clearance of extracellular pathogenic bacteria and fungi. However, this subset is critically involved in the pathology of many autoimmune diseases, e.g., psoriasis, multiple sclerosis, allergy, rheumatoid arthritis, and inflammatory bowel diseases in humans. Therefore, Th17 responses need to be tightly regulated in vivo to mediate effective host defenses against pathogens without causing excessive host tissue damage. Foxp3(+) regulatory T (Treg) cells play an important role in maintaining peripheral tolerance to self-antigens and in counteracting the inflammatory activity of effector T helper cell subsets. Although Th17 and Treg cells represent two CD4(+) T cell subsets with opposing principal functions, these cell types are functionally connected. In this review, we will first give an overview on the biology of Th17 cells and describe their development and in vivo function, followed by an account on the special developmental relationship between Th17 and Treg cells. We will describe the identification of Treg/Th17 intermediates and consider their lineage stability and function in vivo. Finally, we will discuss how Treg cells may regulate the Th17 cell response in the context of infection and inflammation, and elude on findings demonstrating that Treg cells can also have a prominent function in promoting the differentiation of Th17 cells