Biotite (Black Mica) as an Adsorbent of Pesticides in Aqueous Solution

Chemical contamination of water resources on the planet generates a range of environmental disturbances which impair ecosystems. Humans ingest such chemicals often present in water. Conventional treatments fail to remove these contaminants from water, requiring complementary methods such as activated carbon filters, reverse osmosis, or distillation, which are expensive and seldom used in the public water supply. In recent years, there has been a search for alternative eco-friendly, low-cost methods which can effectively remove these contaminants. This study was conducted to test the effectiveness of biotite (black mica), an igneous mineral of the mica group, in removing pesticides from water. A trial was designed to assess the rate of pesticide removal using a methodology based on axes of variation of pH, temperature, concentration,and time. The pesticides tested were atrazine, fluazifopp- butyl, lambda-cyhalothrin, chlorpyrifos, and lactofen. The results showed higher removal rates in acidic conditions (pH 3) and temperatures between 20 and 30 °C, requiring about 6 h to reach maximum adsorption. More than 80 % of all the pesticides were adsorbed. The best result was obtained for fluazifop (94.2 %) in 6 h, under pH 3, and temperature of 25 °C. The study revealed that biotite has a high absorption capacity of complex and varied compounds. These findings signal the need for further studies and tests. Due to the high cost of pesticide analysis, which can only be made using a chromatograph mass spectrometer, financial resources will be required.CNPq (National Counsel of Technological and Scientific Development-Brazil) for the scholarship granted

Direitos humanos, paz, sustentabilidade e empresas globais: coletânea REDHIPAS

- Divulgação dos SUMÁRIOS das obras recentemente incorporadas ao acervo da Biblioteca Ministro Oscar Saraiva do STJ. Em respeito à Lei de Direitos Autorais, não disponibilizamos a obra na íntegra.- Localização na estante: 342.7 D598hg- Organizado por: Ana Luiza da Gama e Souza, Lara Denise Góes da Costa e Leticia Helena Medeiros Veloso

Consumption of Diet Containing Free Amino Acids Exacerbates Colitis in Mice

Dietary proteins can influence the maturation of the immune system, particularly the gut-associated lymphoid tissue, when consumed from weaning to adulthood. Moreover, replacement of dietary proteins by amino acids at weaning has been shown to impair the generation of regulatory T cells in the gut as well as immune activities such as protective response to infection, induction of oral and nasal tolerance as well as allergic responses. Polymeric and elemental diets are used in the clinical practice, but the specific role of intact proteins and free amino acids during the intestinal inflammation are not known. It is plausible that these two dietary nitrogen sources would yield distinct immunological outcomes since proteins are recognized by the immune system as antigens and amino acids do not bind to antigen-recognition receptors but instead to intracellular receptors such as mammalian target of rapamycin (mTOR). In this study, our aim was to evaluate the effects of consumption of an amino acid-containing diet (AA diet) versus a control protein-containing diet in adult mice at steady state and during colitis development. We showed that consumption of a AA diet by adult mature mice lead to various immunological changes including decrease in the production of serum IgG as well as increase in the levels of IL-6, IL-17A, TGF-β, and IL-10 in the small and large intestines. It also led to changes in the intestinal morphology, to increase in intestinal permeability, in the number of total and activated CD4+ T cells in the small intestine as well as in the frequency of proliferating cells in the colon. Moreover, consumption of AA diet during and prior to development of dextran sodium sulfate-induced colitis exacerbated gut inflammation. Administration of rapamycin during AA diet consumption prevented colitis exacerbation suggesting that mTOR activation was involved in the effects triggered by the AA diet. Therefore, our study suggests that different outcomes can result from the use of diets containing either intact proteins or free amino acids such as elemental, semielemental, and polymeric diets during intestinal inflammation. These results may contribute to the design of nutritional therapeutic intervention for inflammatory bowel diseases

Single Low Dose of Cocaine-Structural Brain Injury Without Metabolic and Behavioral Changes

Chronic cocaine use has been shown to lead to neurotoxicity in rodents and humans, being associated with high morbidity and mortality rates. However, recreational use, which may lead to addictive behavior, is often neglected. This occurs, in part, due to the belief that exposure to low doses of cocaine comes with no brain damage risk. Cocaine addicts have shown glucose metabolism changes related to dopamine brain activity and reduced volume of striatal gray matter. This work aims to evaluate the morphological brain changes underlying metabolic and locomotor behavioral outcome, in response to a single low dose of cocaine in a pre-clinical study. In this context, a Balb-c mouse model has been chosen, and animals were injected with a single dose of cocaine (0.5 mg/kg). Control animals were injected with saline. A behavioral test, positron emission tomography (PET) imaging, and anatomopathological studies were conducted with this low dose of cocaine, to study functional, metabolic, and morphological brain changes, respectively. Animals exposed to this cocaine dose showed similar open field activity and brain metabolic activity as compared with controls. However, histological analysis showed alterations in the prefrontal cortex and hippocampus of mice exposed to cocaine. For the first time, it has been demonstrated that a single low dose of cocaine, which can cause no locomotor behavioral and brain metabolic changes, can induce structural damage. These brain changes must always be considered regardless of the dosage used. It is essential to alert the population even against the consumption of low doses of cocaine