925 research outputs found
Aged Lewis rats exposed to low and moderate doses of rotenone are a good model for studying the process of protein aggregation and its effects upon central nervous system cell physiology
Physiology and nutritional contents of lettuce (Lactuca sativa L.) plants induced by Pseudomonas fluorescens / Fisiologia e conteúdo nutricional de plantas de alface (Lactuca sativa L.) induzidas por Pseudomonas fluorescensv
Sustainable agriculture and the larger scales of production needed to meet the higher demand for food each year have become models for several studies; beneficial microorganisms are one model that has been used as an alternative for greater production of and reductions in the use of chemical fertilizers. Thus, the objective of this work was to study the physiological changes in and nutrient contents of lettuce after inoculation with Pseudomonas fluorescens in combination with chemical fertilization. P. fluorescens had a positive influence on gas exchange, with increases of 41% in A, 44% in Gs, 29% in E, and 100% in A / Ci; increased Concentration of chlorophyll a and b, of 220% more chl a and 106% chl b; increased chlorophyll a fluorescence, higher relative water content; and nutrient content increases of 19% for nitrogen, 24% for phosphorus, and 105% for potassium. Plants inoculated with BRM-32111 presented increases for MFT, MFC and FF, in 37%, 34% and 26% respectively. However, when combined with fertilization, antagonism occurred, and the evaluated parameters were negatively affected
In vitro screening of cytotoxic activity of euphol from Euphorbia tirucalli on a large panel of human cancer-derived cell lines
A large number of classic antineoplastic agents are derived from plants. Euphorbia tirucalli L. (Euphorbiaceae) is a subtropical and tropical plant, used in Brazilian folk medicine against many diseases, including cancer, yet little is known about its true anticancer properties. The present study evaluated the antitumor effect of the tetracyclic triterpene alcohol, euphol, the main constituent of E. tirucalli in a panel of 73 human cancer lines from 15 tumor types. The biological effect of euphol in pancreatic cells was also assessed. The combination index was further used to explore euphol interactions with standard drugs. Euphol showed a cytotoxicity effect against several cancer cell lines (IC50 range, 1.41-38.89 µM), particularly in esophageal squamous cell (11.08 µM) and pancreatic carcinoma cells (6.84 µM), followed by prostate, melanoma, and colon cancer. Cytotoxicity effects were seen in all cancer cell lines, with more than half deemed highly sensitive. Euphol inhibited proliferation, motility and colony formation in pancreatic cancer cells. Importantly, euphol exhibited synergistic interactions with gemcitabine and paclitaxel in pancreatic and esophageal cell lines, respectively. To the best of our knowledge, this study constitutes the largest in vitro screening of euphol efficacy on cancer cell lines and revealed its in vitro anti-cancer properties, particularly in pancreatic and esophageal cell lines, suggesting that euphol, either as a single agent or in combination with conventional chemotherapy, is a potential anti-cancer drug.Amazônia Fitomedicamentos Ltda. (grant no. FITO 05/2012) and Barretos Cancer Hospital, all from Brazilinfo:eu-repo/semantics/publishedVersio
DESENVOLVIMENTO DO FILTRO VIDA
Este trabalho apresenta o projeto de um filtro portátil. O artigo baseado num projeto desenvolvido na disciplina projeto de produto IV aborda temas como design
sustentável, design social e universal. E da ênfase a necessidade do designer está contribuindo para a melhora da qualidade de vida da população, independente da classe social. Além disso, aborda a questão da água, que é uma substancia vital para a sobrevivência da espécie humana
The P450 oxidoreductase, RedA, controls development beyond the mound stage in Dictyostelium discoideum
<p>Abstract</p> <p>Background</p> <p>NADPH-cytochrome-P450 oxidoreductase (CPR) is a ubiquitous enzyme that belongs to a family of diflavin oxidoreductases and is required for activity of the microsomal cytochrome-P450 monooxygenase system. CPR gene-disruption experiments have demonstrated that absence of this enzyme causes developmental defects both in mouse and insect.</p> <p>Results</p> <p>Annotation of the sequenced genome of <it>D. discoideum </it>revealed the presence of three genes (<it>redA</it>, <it>redB </it>and <it>redC</it>) that encode putative members of the diflavin oxidoreductase protein family. <it>redA </it>transcripts are present during growth and early development but then decline, reaching undetectable levels after the mound stage. <it>redB </it>transcripts are present in the same levels during growth and development while <it>redC </it>expression was detected only in vegetative growing cells. We isolated a mutant strain of <it>Dictyostelium discoideum </it>following restriction enzyme-mediated integration (REMI) mutagenesis in which <it>redA </it>was disrupted. This mutant develops only to the mound stage and accumulates a bright yellow pigment. The mound-arrest phenotype is cell-autonomous suggesting that the defect occurs within the cells rather than in intercellular signaling.</p> <p>Conclusion</p> <p>The developmental arrest due to disruption of <it>redA </it>implicates CPR in the metabolism of compounds that control cell differentiation.</p
O professor de l?ngua portuguesa como elaborador de seu pr?prio material did?tico para o aluno surdo
A presente pesquisa tem como objetivo analisar o perfil necess?rio para o professor de L?ngua
Portuguesa como elaborador do seu pr?prio material did?tico para o aluno surdo. Enfatizamos as
caracter?sticas e a relev?ncia dele ser produtor do seu material did?tico, assim como ter as compet?ncias e
as habilidades necess?rias para o Ensino do Portugu?s como segunda l?ngua para o aluno surdo. Desse
modo, nossa abordagem foi de cunho qualitativo, tendo como tipo de pesquisa a bibliogr?fica e explorat?ria.
Elaborada a partir de trabalhos acad?micos nos anos de 2014-2020. Utilizamos os seguintes autores para
nortear essa pesquisa: M?ximo (2020), Liberali (2008), Geraldi (1996), Koch(2006), Bezerra (2002),
Botelho (2005). Como resultados obtidos, constatamos a necessidade do professor ser aut?nomo, inovador
e respons?vel, mantendo uma postura reflexiva e cr?tica na sua pr?tica em sala de aula. Assim, o professor
ter dom?nio da L?ngua de Sinais e da cultura surda contribuir? para que possa ser um ex?mio produtor de
material did?tico
Prevalência de enteroparasitoses em crianças de creches públicas da cidade de Belo Horizonte, Minas Gerais, Brasil
The objective of this study was to verify the occurrence of intestinal parasites in 3 to 6-year-old children from daycare centers maintained by the municipal government of Belo Horizonte, Minas Gerais, Brazil. Coproparasitological tests performed in 472 children have shown that 24.6% of them had some type of parasites, 6.6% of the children having more than one type. Among protozoa, Entamoeba coli (14.0%) and G. duodenalis (9.5%) were the most prevalent, whereas Ascaris lumbricoides (3.0%) and Trichuris trichiura (1.1%) were the most frequent among the helminths. Thus, we can observe that intestinal parasites still represent a serious public health problem in Belo Horizonte, especially among children and in areas where the socioeconomic conditions are less favorable.O objetivo deste trabalho foi verificar a ocorrência de parasitos intestinais em crianças de 3 a 6 anos de idade, oriundas de creches mantidas pela Prefeitura Municipal de Belo Horizonte, Minas Gerais, Brasil. Exames coproparasitológicos realizados em 472 crianças demonstraram que 24,6% apresentavam algum tipo de parasitose, sendo que 6,6% apresentavam mais de um parasito. Entre os protozoários, Entamoeba coli (14,0%) e G. duodenalis (9,5%) foram os mais prevalentes, enquanto Ascaris lumbricoides (3,0%) e Trichuris trichiura (1,1%) foram os mais encontrados entre os helmintos. Desta forma, observa-se que as parasitoses intestinais ainda são um problema de saúde pública em Belo Horizonte, principalmente entre a população infantil e em áreas onde as condições sócio-econômicas são menos favoráveis
Soil loss risk and habitat quality in streams of a meso-scale river basin
Soil loss expectation and possible relationships among soil erosion, riparian vegetation and water quality were studied in the São José dos Dourados River basin, State of São Paulo, Brazil. Through Geographic Information System (GIS) resources and technology, Soil Loss Expectation (SLE) data obtained using the Universal Soil Loss Equation (USLE) model were analyzed. For the whole catchment area and for the 30 m buffer strips of the streams of 22 randomly selected catchments, the predominant land use and habitat quality were studied. Owing mainly to the high soil erodibility, the river basin is highly susceptible to erosive processes. Habitat quality analyses revealed that the superficial water from the catchments is not chemically impacted but suffers physical damage. A high chemical purity is observed since there are no urban areas along the catchments. The water is physically poor because of high rates of sediment delivery and the almost nonexistence of riparian vegetation.Expectativa de perda de solo e possíveis relações entre erosão, vegetação ripária e qualidade da água foram estudados na bacia do rio São José dos Dourados (SP). Através de recursos de geoprocessamento e da Equação Universal de Perda de Solos, os dados sobre expectativa de perda de solo foram levantados. Para a área de drenagem total e a faixa tampão dos corpos d'água de 22 sub-bacias aleatoriamente selecionadas, analisou-se a cobertura do solo predominante e qualidade do habitat. Devido principalmente à alta erodibilidade do solo, a área estudada é altamente suscetível ao processo erosivo. As análises de qualidade da água revelaram que as águas superficiais das sub-bacias estão quimicamente não impactadas, mas fisicamente degradadas. A alta pureza química deve-se, possivelmente, à ausência de áreas urbanizadas ao longo das sub-bacias e as alterações nas características físicas são, possivelmente, decorrentes das altas taxas de transferência de sedimento aos corpos d'água e à quase ausência de mata ciliar
Examining the Effect of Charged Lipids on Mitochondrial Outer Membrane Dynamics Using Atomistic Simulations
The outer mitochondrial membrane (OMM) is involved in multiple cellular functions such as apoptosis, inflammation and signaling via its membrane-associated and -embedded proteins. Despite the central role of the OMM in these vital phenomena, the structure and dynamics of the membrane have regularly been investigated in silico using simple two-component models. Accordingly, the aim was to generate the realistic multi-component model of the OMM and inspect its properties using atomistic molecular dynamics (MD) simulations. All major lipid components, phosphatidylinositol (PI), phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidylserine (PS), were included in the probed OMM models. Because increased levels of anionic PS lipids have potential effects on schizophrenia and, more specifically, on monoamine oxidase B enzyme activity, the effect of varying the PS concentration was explored. The MD simulations indicate that the complex membrane lipid composition (MLC) behavior is notably different from the two-component PC-PE model. The MLC changes caused relatively minor effects on the membrane structural properties such as membrane thickness or area per lipid; however, notable effects could be seen with the dynamical parameters at the water-membrane interface. Increase of PS levels appears to slow down lateral diffusion of all lipids and, in general, the presence of anionic lipids reduced hydration and slowed down the PE headgroup rotation. In addition, sodium ions could neutralize the membrane surface, when PI was the main anionic component; however, a similar effect was not seen for high PS levels. Based on these results, it is advisable for future studies on the OMM and its protein or ligand partners, especially when wanting to replicate the correct properties on the water-membrane interface, to use models that are sufficiently complex, containing anionic lipid types, PI in particular
The effect of pH on the simultaneous determination of Sulfamethoxazole and Trimethoprim by Ultraviolet Spectrophotometry and Multivariate Calibration
Analytical techniques based on Ultraviolet (UV) spectrophotometry are widely used in pharmaceutical analysis, because they are simple and inexpensive. The choice of pH is critical in the development of univariate methods for pharmaceutical quantitation by UV spectrophotometry since changes may modify the absorption spectrum profile. Similar to univariate methods by UV spectrophotometry changes in pH may influence the predictive ability of multivariate models, affecting the resultant analytical performance. We report herein on the influence of pH on the simultaneous determination of sulfamethoxazole (SMZ) and trimethoprim (TMP) in tablets using UV spectrophotometry and multivariate calibration. Data were recorded using a UV spectrophotometer in the wavelength range of 200 to 350 nm. The experimental matrix was constructed using 36 synthetic samples of SMZ-TMP mixtures. The concentration ranges used for the investigation were 14.0 to 26.0 mg L-1 for SMZ and 2.8 to 5.2 mg L-1 for TMP. The Partial Least Squares (PLS) regression models were generated with full-spectrum and multiple pH levels. At pH 4.3, lower values of relative standard error of prediction (RSEP %) for SMZ (1.83) and TMP (1.13) were obtained. The PLS model at pH 4.3 was used for the quantification of real samples (tablets obtained from 13 different manufacturers) and the results were compared with conventional procedures using high performance liquid chromatography (HPLC).
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