877 resultados para burns
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gp330/megalin, a member of the low density lipoprotein (LDL) receptor gene family, is expressed on the apical surfaces of epithelial tissues, including the neuroepithelium, where it mediates the endocytic uptake of diverse macromolecules, such as cholesterol-carrying lipoproteins, proteases, and antiproteinases. Megalin knockout mice manifest abnormalities in epithelial tissues including lung and kidney that normally express the protein and they die perinatally from respiratory insufficiency. In brain, impaired proliferation of neuroepithelium produces a holoprosencephalic syndrome, characterized by lack of olfactory bulbs, forebrain fusion, and a common ventricular system. Similar syndromes in humans and animals are caused by insufficient supply of cholesterol during development. Because megalin can bind lipoproteins, we propose that the receptor is part of the maternal-fetal lipoprotein transport system and mediates the endocytic uptake of essential nutrients in the postgastrulation stage.
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The lack of efficient mechanisms for stable genetic transformation of medically important insects, such as anopheline mosquitoes, is the single most important impediment to progress in identifying novel control strategies. Currently available techniques for foreign gene expression in insect cells in culture lack the benefit of stable inheritance conferred by integration. To overcome this problem, a new class of pantropic retroviral vectors has been developed in which the amphotropic envelope is completely replaced by the G glycoprotein of vesicular stomatitis virus. The broadened host cell range of these particles allowed successful entry, integration, and expression of heterologous genes in cultured cells of Anopheles gambiae, the principle mosquito vector responsible for the transmission of over 100 million cases of malaria each year. Mosquito cells in culture infected with a pantropic vector expressing hygromycin phosphotransferase from the Drosophila hsp70 promoter were resistant to the antibiotic hygromycin B. Integrated provirus was detected in infected mosquito cell clones grown in selective media. Thus, pantropic retroviral vectors hold promise as a transformation system for mosquitoes in vivo.
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Photolithographic micromachining of silicon is a candidate technology for the construction of high-throughput DNA analysis devices. However, the development of complex silicon microfabricated systems has been hindered in part by the lack of a simple, versatile pumping method for integrating individual components. Here we describe a surface-tension-based pump able to move discrete nanoliter drops through enclosed channels using only local heating. This thermocapillary pump can accurately mix, measure, and divide drops by simple electronic control. In addition, we have constructed thermal-cycling chambers, gel electrophoresis channels, and radiolabeled DNA detectors that are compatible with the fabrication of thermocapillary pump channels. Since all of the components are made by conventional photolithographic techniques, they can be assembled into more complex integrated systems. The combination of pump and components into self-contained miniaturized devices may provide significant improvements in DNA analysis speed, portability, and cost. The potential of microfabricated systems lies in the low unit cost of silicon-based construction and in the efficient sample handling afforded by component integration.
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A pantropic pseudotyped retroviral vector containing the envelope protein of vesicular stomatitis virus was used as a gene transfer vector in the dwarf surfclam, Mulinia lateralis. These pantropic retroviral vectors have an extremely broad host cell range and can infect many nonmammalian species. Newly fertilized dwarf surfclam eggs were electroporated at 700 V in the presence of 1 x 10(4) colony-forming units of pantropic pseudotyped retroviral particles. Infection was well tolerated and did not affect the survival rate of the embryos. Gametes collected from P1 presumptive transgenic animals were analyzed for the presence of provirus by PCR, and in different experiments 13-33% of the gamete pools were positive for the transgene. Dot blot hybridization of DNA samples from the F1 offspring of two different crosses between infected P1 and wild-type individuals revealed that 28% and 31% of F1 offspring were transgenic, respectively. Southern blot analysis of DNA isolated from PCR-positive F1 animals confirmed integration of a single copy of the provirus into the host genome. Thus, the germ lines of these two P1 transgenic animals were mosaic for the transgene. Expression of beta-galactosidase encoded by the provirus was detected in transgenic but not control surfclam embryos. Pantropic pseudotyped retroviral vectors provide a useful method for the stable introduction of foreign genetic information into surfclams and may facilitate the introduction of desirable genetic traits into commercially important shellfish and crustaceans.
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Protein kinase C (PKC) is involved in the proliferation and differentiation of many cell types. In human erythroleukemia (K-562) cells, the PKC isoforms alpha and beta II play distinct functional roles. alpha PKC is involved in phorbol 12-myristate 13-acetate-induced cytostasis and megakaryocytic differentiation, whereas beta II PKC is required for proliferation. To identify regions within alpha and beta II PKC that allow participation in these divergent pathways, we constructed chimeras in which the regulatory and catalytic domains of alpha and beta II PKC were exchanged. These PKC chimeras can be stably expressed, exhibit enzymatic properties similar to native alpha and beta II PKC in vitro, and participate in alpha and beta II PKC isotype-specific pathways in K-562 cells. Expression of the beta/alpha PKC chimera induces cytostasis in the same manner as overexpression of wild-type alpha PKC. In contrast, the alpha/beta II PKC chimera, like wild-type beta II PKC, selectively translocates to the nucleus and leads to increased phosphorylation of the nuclear envelope polypeptide lamin B in response to bryostatin-1. Therefore, the catalytic domains of alpha and beta II PKC contain determinants important for alpha and beta II PKC isotype function. These results suggest that the catalytic domain represents a potential target for modulating PKC isotype activity in vivo.
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Conventional myosin II is an essential protein for cytokinesis, capping of cell surface receptors, and development of Dictyostelium cells. Myosin II also plays an important role in the polarization and movement of cells. All conventional myosins are double-headed molecules but the significance of this structure is not understood since single-headed myosin II can produce movement and force in vitro. We found that expression of the tail portion of myosin II in Dictyostelium led to the formation of single-headed myosin II in vivo. The resultant cells contain an approximately equal ratio of double- and single-headed myosin II molecules. Surprisingly, these cells were completely blocked in cytokinesis and capping of concanavalin A receptors although development into fruiting bodies was not impaired. We found that this phenotype is not due to defects in myosin light chain phosphorylation. These results show that single-headed myosin II cannot function properly in vivo and that it acts as a dominant negative mutation for myosin II function. These results suggest the possibility that cooperativity of myosin II heads is critical for force production in vivo.
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Rho-dependent transcription termination at certain terminators in Escherichia coli also depends on the presence of NusG [Sullivan, S. L. & Gottesman, M. E. (1992) Cell 68, 989-994]. We have found that termination at the first intragenic terminator in lacZ (tiZ1) is strongly dependent on NusG when transcription is done in vitro with the concentrations of NTPs found in vivo. With a lower level of NTPs, and consequently a slower rate of RNA-chain growth, Rho causes some termination by itself that is enhanced with NusG. These results suggest that NusG serves to overcome a kinetic limitation of Rho to function at certain terminators. At a second intragenic terminator within the lacZ reading frame (tiZ2) the efficiency of Rho-mediated termination was unaffected by either NusG or by RNA polymerase elongation kinetics. Thus, using purified components and intracellular levels of NTPs, we have confirmed the in vivo finding that certain Rho-dependent terminators also depend on NusG, whereas others do not.
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The rat cell line REF52 is not permissive for gene amplification. Simian virus 40 tumor (T) antigen converts these cells to a permissive state, as do dominant negative mutants of p53, suggesting that the effect of T antigen is due mainly to its ability to bind to p53. To manipulate permissivity, we introduced a temperature-sensitive mutant of T antigen (tsA58) into REF52 cells and selected for resistance to N-(phosphonacetyl)-L-aspartate (PALA). Most freshly isolated PALA-resistant colonies, each of approximately 200 cells, selected at a permissive temperature, arrested when shifted to a nonpermissive temperature. Growth arrest was stable, with no evidence of apoptosis, as long as T antigen was absent but was reversed when T antigen was restored. In contrast, PALA-resistant clones grown to approximately 10(7) cells at a permissive temperature did not arrest when shifted to a nonpermissive temperature. All PALA-resistant clones examined had amplified carbamoyl-phosphate synthetase-aspartate transcarbamoylase-dihydroorotase (CAD) genes, present in structures consistent with a mechanism involving bridge-breakage-fusion (BBF) cycles. We propose that p53-mediated growth arrest operates only early during the complex process of gene amplification, when newly formed PALA-resistant cells contain broken DNA, generated in BBF cycles. During propagation under permissive conditions, the broken DNA ends are healed, and, even though the p53-mediated pathway is still intact at a nonpermissive temperature and the cells contain amplified DNA, they are not arrested in the absence of broken DNA. The data support the hypothesis that BBF cycles are an important mechanism of amplification and that the broken DNA generated in each cycle is a key signal that regulates permissivity for gene amplification.
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As queimaduras na infância compreendem importante causa de atendimento hospitalar e internação e podem desencadear sequelas físicas e emocionais. Dependendo da gravidade e complexidade das lesões, a hospitalização da criança é prolongada para realização de tratamento adequado e ela é afastada tanto do convívio familiar como do social. O número de crianças em idade escolar que sofrem queimaduras, e consequentemente interrompem as atividades escolares, por períodos curtos ou até as abandonam, é significativo, tornando digno de preocupação o processo de reinserção escolar. Este estudo teve como objetivo interpretar os significados do processo de reinserção escolar de crianças sobreviventes de queimaduras. Realizou-se uma pesquisa com abordagem metodológica qualitativa, fundamentada no referencial teórico da Antropologia Interpretativa e no método etnográfico. Após a aprovação do estudo pelos Comitês de Ética em Pesquisa com Seres Humanos das instituições envolvidas, convidaram-se crianças sobreviventes de queimaduras em seguimento em um hospital-escola do interior paulista. Coletaram-se dados no hospital, no domicílio e na escola das crianças, de janeiro de 2012 a dezembro de 2013, por meio de entrevistas em profundidade audiogravadas e observação participante, complementadas pelo diário de campo. Participaram da pesquisa 14 crianças e os atores sociais envolvidos neste processo, como familiares, profissionais de saúde, professores, vizinha e amigo, totalizando 57 participantes. A coleta e análise dos dados ocorreram concomitantemente, e esta última seguiu os pressupostos da análise temática indutiva. Identificaram-se códigos, os quais, posteriormente, embasaram a construção das duas unidades de sentidos: \"Fatos e fatores prévios ao retorno escolar\" e \"A volta à escola\". A partir destas, identificou-se o núcleo temático, \"O olho puxa essas coisas. A gente olha mesmo\": enxergando o outro como diferente, o qual apresenta a explicação compreensiva do processo de reinserção escolar, fornecendo os significados da experiência. Os significados foram explicados por meio dos conceitos antropológicos de estigma, identidade e corporeidade. O culto ao corpo presente no contexto cultural brasileiro foi fator intensificador do estigma sofrido pelas crianças. Identificaram-se fatores facilitadores do processo, como: dar continuidade às atividades escolares e manter contato com professores e colegas durante a hospitalização; preparar a escola para receber a criança; abordar sobre queimadura na escola para evitar curiosidade; encarar a presença da discriminação e trabalhar as diferenças. Estas estratégias fazem com que todos os envolvidos se sintam ao menos mais confortáveis durante esse difícil processo que merece atenção e envolvimento dos familiares, profissionais de saúde e equipe escolar. A partir dos resultados desta pesquisa, esperamos empoderar as crianças e seus familiares acerca da melhor maneira para lidar com as queimaduras durante a reinserção escolar e contribuir para o desenvolvimento de ações e estratégias baseadas na cultura para que este processo ocorra da forma menos traumática possível
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Chronic wasting disease is a fatal neurological disease found in deer and elk in 14 western and mid-western states and two Canadian provinces. It is believed to have been first observed in Colorado and Wyoming in 1967. It is a disease caused by prions by an unknown transmission vector and impossible to cure at this time. Most of the management options currently available are labor-intensive and costly. The potential use of controlled burns to reduce or eliminate the prions that cause the disease was shown to have no effect on the prevalence of the disease in either study area. The temperatures needed to destroy prions were not reached by either surface or crown fires.
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This book contains 19 essays that have been written by current LIS Students who were enrolled in the LIS4330: Library Instruction class at the University of Denver, 2016. Designed to provide a short and pithy overview of a topic that is related to instruction, education, or information literacy, each essays aims to be accessible and approachable for time-pressed librarians who may not have time to catch up.
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Introducción: El estudio ATHAC recoge datos sobre heridas agudas y crónicas que son candidatas a un tratamiento a base de apósitos grasos neutros como la gama URGOTUL. Objetivos: Describir las características de las heridas, describir los tratamiento aplicados a estas heridas y explorar las opiniones de los profesionales de enfermería y los pacientes sobre los tratamientos en términos de aplicabilidad, adaptabilidad y confort para el paciente. Material y métodos: 1.500 pacientes fueron incluidos en el estudio de acuerdo al tipo de herida y a los tratamientos en uso. Se recogieron datos a partir de dos cuestionarios: uno para el paciente y otro para la enfermera responsable de sus cuidados. Las enfermeras recogieron los datos en el primer día de inclusión y los pacientes respondían al cuestionario 1 mes más tarde o antes si la herida había cicatrizado. Las variables recogidas por la enfermera fueron: datos sociodemográficos, etiología de las lesiones, características y localización de las heridas, aspectos y opiniones sobre el tratamiento. A los pacientes se les preguntó por la duración del tratamiento, el estado de la lesión en el momento de contestar y desde su punto de vista, así como su opinión sobre el dolor, satisfacción general y aceptabilidad. Se llevaron a cabo análisis descriptivos uni y bivariados. Para cada paciente, si tenía más de una lesión, se recogieron datos de la lesión de mayor tamaño. Resultados: Finalmente, se estudiaron 1.432 pacientes con una o más lesiones (420 tenían más de una lesión). El 60,4% eran mujeres y la edad media fue de 66 ± 19 años. En el caso de las heridas crónicas (657 lesiones) predominaron las úlceras venosas (47%) y las úlceras por presión (23%). En las heridas agudas (775 lesiones), la mayoría fueron traumáticas (41%) y quemaduras (32,5%). La principal localización en todas las lesiones fueron los miembros inferiores (57,4% en heridas crónicas y 39% en agudas). El 84,4% de los casos indicó presentar algún tipo de dolor previo al comienzo de este estudio. Al finalizar el estudio, un porcentaje menor del 20% indicó presentar algún tipo de dolor. El 72% de las heridas agudas y el 35% de las crónicas, como refieren los pacientes, había cicatrizado al finalizar el estudio (en un tiempo medio de entre 20-40 días). El 54% de las heridas crónicas evoluciona favorablemente y el 26% de las agudas. Más del 80% de las heridas estudiadas fueron tratadas con la gama URGOTUL. Conclusión: URGOTUL es una buena opción para el tratamiento de este tipo de heridas, especialmente para las heridas agudas, en relación a su carácter atraumático y a su capacidad de cicatrización, así como la buena aceptación y satisfacción de los pacientes.
Resumo:
Aunque los apósitos de cura en ambiente (CAH) húmedo se han utilizado predominantemente en heridas crónicas, ello no es óbice para que su uso en heridas agudas permita solucionar algunos problemas, como el conseguir un ambiente óptimo que facilite la migración epitelial, así como una adecuada protección de las heridas y una correcta gestión del exudado. Es por ello que, dentro del marco del estudio AURIGA-04, nos planteamos la realización de un estudio prospectivo observacional, abierto y multicéntrico, de medidas repetidas en una cohorte de pacientes que presentan heridas agudas de diversa etiología en el que se incluyeron pacientes con heridas traumáticas, quirúrgicas o quemaduras tratados por profesionales de Atención Primaria, con el objetivo de generar evidencias acerca de la utilización de apósitos de CAH, en concreto, de la gama de apósitos hidrocelulares Allevyn®, en el tratamiento de heridas agudas. Se consideraron como criterios de exclusión heridas con signos clínicos de infección. Solo se incluyó una lesión por paciente. En el caso de los pacientes con heridas agudas, la muestra a estudio quedó compuesta por 61 pacientes con una edad media de 71,1 años; 36 casos corresponden a mujeres (60%). El estado general de salud de la muestra era bueno en un 49,1% de los casos y prácticamente la totalidad de los pacientes presentaba pluripatología. Un 10% de los pacientes consumía fármacos que podían interferir en la cicatrización y un 6% presentaba malnutrición. El 67,2% de las lesiones eran heridas traumáticas, el 24,6% quirúrgicas y un 8,2% quemaduras. Un 37% de las lesiones fueron clasificadas como superficiales y el 63% restante como profundas. Presentaban 64 días de evolución previa a su inclusión en el estudio y una superficie media de 23,34 cm2. Los pacientes permanecieron en el estudio un promedio de 43,6 días, con una cadencia de cambios de apósito cada 2,7 días. Durante el estudio cicatrizaron el 63,9% de las heridas, en un promedio de 40,9 días. La superficie inicial de las lesiones mostró una reducción significativa a lo largo del seguimiento (inicial: 23,34 cm2, final: 4,27 cm2, p ≤ 0,001). En los modelos de regresión de Cox, sólo resultó estadísticamente significativa la edad del paciente, en el grupo de lesiones traumáticas (RR: –0,03, p= 0,039). Durante el período de seguimiento, un 80,3% de los pacientes fue tratado en combinación con Intrasite Conformable®, Iruxol Mono® o la combinación de ambos productos. Los profesionales que realizaron las curas con Allevyn® valoraron muy favorablemente su manejo durante todo el estudio; así, en más del 96% de los cambios se consideró fácil de colocar, en el 100% indoloro y también en el 100% de fácil retirada. A la vista de los resultados, los apósitos de CAH y, en concreto, la gama de apósitos Allevyn®, tienen una clara aplicación en el caso de las heridas agudas, permitiendo un óptimo abordaje local de las lesiones, proporcionando unos niveles óptimos de humedad, pH y temperatura para las células implicadas en el proceso de cicatrización. Así, se promueve la formación de tejido de granulación y facilita la epitelización, además de proteger la herida ante traumatismos y gérmenes.
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In the chemical textile domain experts have to analyse chemical components and substances that might be harmful for their usage in clothing and textiles. Part of this analysis is performed searching opinions and reports people have expressed concerning these products in the Social Web. However, this type of information on the Internet is not as frequent for this domain as for others, so its detection and classification is difficult and time-consuming. Consequently, problems associated to the use of chemical substances in textiles may not be detected early enough, and could lead to health problems, such as allergies or burns. In this paper, we propose a framework able to detect, retrieve, and classify subjective sentences related to the chemical textile domain, that could be integrated into a wider health surveillance system. We also describe the creation of several datasets with opinions from this domain, the experiments performed using machine learning techniques and different lexical resources such as WordNet, and the evaluation focusing on the sentiment classification, and complaint detection (i.e., negativity). Despite the challenges involved in this domain, our approach obtains promising results with an F-score of 65% for polarity classification and 82% for complaint detection.
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The present work has two dimensions: analytical and environmental. On the one hand we proved that thermogravimetric analysis can be used to perform fast characterization of oil refinery sludge. To this end, thermogravimetric curves were deconvoluted by using autocatalytic kinetics to take into account acceleratory phases in a thermal degradation performed in oxygen-containing atmosphere or at high heating rates. Based on thermogravimetric results, oil refinery sludge was modeled in terms of various fractions (pseudo-components) which degrade as major oil cuts. On the other hand, as an alternative to landfill, we have seen that Soxhlet extraction allows recovery almost half of the weight of sludge as a mixture of hydrocarbons, similar to gas–oil, which burns without residue. This ensures both, waste inerting and significant reduction in sludge volume.