RESUMO
This paper presents a comparison of six index properties collected during durability inspections of five Mexican seaports. Typical durability indicators such as compressive strength, saturated electrical resistivity, ultrasonic pulse velocity, percent total void content, capillary porosity, and chloride concentration profiles were analyzed to obtain empirical correlations with the non-steady-state chloride diffusion coefficient. These indices were compared to determine correlation coefficients that are the most important for obtaining better corrosion initiation forecasting. Two models of corrosion initiation time (ti) were used: Fick's second law of diffusion and the reported UNE-83994-2 (Spanish Association for Standardization, UNE) in which electrical resistivity was used to calculate concrete service life. The data from both models were cleaned using correlated variables, and the initial variables were compared with ti. The main result achieved was the verification of the feasibility of using correlations of variables to clean unnecessary data in order to calculate ti. Additionally, electrical resistivity was identified as one of the main durability indexes for in-service concrete structures exposed to marine environments. This is important because electrical resistivity is a non-destructive and reliable test that can be measured both in the laboratory and in the field very easily.
RESUMO
The plasma membrane forms a permeable barrier that separates the cytoplasm from the external environment, defining the physical and chemical limits in each cell in all organisms. The movement of molecules and ions into and out of cells is controlled by the plasma membrane as a critical process for cell stability and survival, maintaining essential differences between the composition of the extracellular fluid and the cytosol. In this process aquaporins (AQPs) figure as important actors, comprising highly conserved membrane proteins that carry water, glycerol and other hydrophilic molecules through biomembranes, including the cell wall and membranes of cytoplasmic organelles. While mammals have 15 types of AQPs described so far (displaying 18 paralogs), a single plant species can present more than 120 isoforms, providing transport of different types of solutes. Such aquaporins may be present in the whole plant or can be associated with different tissues or situations, including biotic and especially abiotic stresses, such as drought, salinity or tolerance to soils rich in heavy metals, for instance. The present review addresses several aspects of plant aquaporins, from their structure, classification, and function, to in silico methodologies for their analysis and identification in transcriptomes and genomes. Aspects of evolution and diversification of AQPs (with a focus on plants) are approached for the first time with the aid of the LCA (Last Common Ancestor) analysis. Finally, the main practical applications involving the use of AQPs are discussed, including patents and future perspectives involving this important protein family.
Assuntos
Aquaporinas , Proteínas de Plantas , Plantas/química , Aquaporinas/genética , Aquaporinas/metabolismo , Biotecnologia , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
Human immunodeficiency virus (HIV) infection can cause neuropsychiatric disorders such as cognitive impairment, behavioural difficulties or psychiatric symptoms –for instance, mania and psychosis. HIV patients with psychiatric comorbidities need an appropriate treatment which tackles the HIV infection as much as the particular mental symptoms. Here we present the case of a patient suffering from delusions, which turned out to be caused by encephalitis secondary to a previously unknown HIV infection. A review of psychosis in HIV-infected patients is also presented. This review is focused on the epidemiology, etiopathogenesis and clinical presentation of HIV-induced psychosis, as well as the recommended pharmacological treatment (antiretroviral therapy and antipsychotic medication) and the expected treatment response. We also present wide information concerning pharmacological interactions between antiretroviral and antipsychotic medications that we hope will help the clinician to better manage this complex condition.
Assuntos
Infecções por HIV/complicações , Transtornos Psicóticos/tratamento farmacológico , Transtornos Psicóticos/etiologia , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
BACKGROUND & AIMS: Nucleoplasmic Ca(2+) regulates cell growth in the liver, but the proteins through which this occurs are unknown. METHODS: We used Rapid Subtraction Hybridization (RaSH) to subtract genes in SKHep1 liver cells expressing the Ca(2+) buffer protein parvalbumin (PV) targeted to the nucleus, from genes in cells expressing a mutated form of nuclear-targeted PV which has one of two Ca(2+)-binding sites inactivated. The subtraction permitted the selection of genes whose expression was affected by a small alteration in nuclear Ca(2+) concentration. RESULTS: The asparaginyl endopeptidase legumain (LGMN) was identified in this screening. When Ca(2+) was buffered in the nucleus of SKHep1 cells, LGMN mRNA was decreased by 97%, in part by a transcriptional mechanism, and decreased expression at the protein level was observed by immunoblot and immunofluorescence. Treatment with hepatocyte growth factor increased LGMN expression. Knockdown of LGMN by siRNA decreased proliferation of SKHep1 cells by â¼50% as measured both by BrdU uptake and mitotic index, although an inhibitor of LGMN activity did not affect BrdU incorporation. A significant reduction in the fraction of cells in G2/M phase was seen as well. This was associated with increases in the expression of cyclins A and E. Furthermore, LGMN expression was increased in hepatocellular carcinoma cells relative to normal hepatocytes in the same specimens. CONCLUSIONS: These findings suggest a new role for LGMN and provide evidence that nuclear Ca(2+) signals regulate cell proliferation in part through the modulation of LGMN expression. Increased expression of LGMN may be involved in liver carcinogenesis.
Assuntos
Sinalização do Cálcio/fisiologia , Cálcio/metabolismo , Proliferação de Células , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , RNA Mensageiro/metabolismo , Carcinoma Hepatocelular/metabolismo , Núcleo Celular/metabolismo , Cisteína Endopeptidases/fisiologia , Pontos de Checagem da Fase G2 do Ciclo Celular , Técnicas de Silenciamento de Genes , Hepatócitos/metabolismo , Humanos , Células Tumorais CultivadasRESUMO
Las consecuencias fisiopatológicas y terapéuticas de los pacientes con trauma y con shock hemorrágico grave son causas de la alta mortalidad que muchas veces se escapan de nuestro control. Son la acidosis, la hipotermia y la coagulopatía las complicaciones que irremediablemente llevan a la muerte a los pacientes cuando no son previstas o prevenidas adecuadamente, y nos obligan a postergar el tratamiento quirúrgico definitivo con el objetivo de lograr una mayor supervivencia, mediante pasos consecutivos y ordenados basados en la tolerancia fisiológica del paciente, elemento este que hasta hace alrededor de una década no se tenía en cuenta en la reanimación del paciente con trauma grave. Estas estrategias han sido denominadas "cirugía de control de daños". En este trabajo nos propusimos realizar una revisión de las causas, consecuencias y tratamiento de los componentes de la tríada mortal para un mejor manejo del paciente traumatizado grave...(AU)
Assuntos
Humanos , Adulto , Traumatismo Múltiplo/complicações , Acidose/terapia , Hipotermia/terapia , Transtornos da Coagulação Sanguínea/terapia , Acidose/etiologia , Hipotermia/etiologia , /etiologia , Ressuscitação , Taxa de SobrevidaRESUMO
Las consecuencias fisiopatológicas y terapéuticas de los pacientes con trauma y con shock hemorrágico grave son causas de la alta mortalidad que muchas veces se escapan de nuestro control. Son la acidosis, la hipotermia y la coagulopatía las complicaciones que irremediablemente llevan a la muerte a los pacientes cuando no son previstas o prevenidas adecuadamente, y nos obligan a postergar el tratamiento quirúrgico definitivo con el objetivo de lograr una mayor supervivencia, mediante pasos consecutivos y ordenados basados en la tolerancia fisiológica del paciente, elemento este que hasta hace alrededor de una década no se tenía en cuenta en la reanimación del paciente con trauma grave. Estas estrategias han sido denominadas "cirugía de control de daños". En este trabajo nos propusimos realizar una revisión de las causas, consecuencias y tratamiento de los componentes de la tríada mortal para un mejor manejo del paciente traumatizado grave...
Assuntos
Humanos , Adulto , Acidose , Transtornos da Coagulação Sanguínea , Hipotermia , Traumatismo Múltiplo/complicações , Taxa de Sobrevida , RessuscitaçãoRESUMO
El Divertículo de Meckel es la anomalía congénita más frecuente del intestino delgado, es el resultado de una obliteración incompleta del conducto onfalomesentérico, es único, verdadero y se sitúa en el borde antimesentérico a unos 90 cm del íleon terminal. El propósito fundamental de este trabajo fue determinar la incidencia de esta entidad en el Servicio de Cirugía General del Hospital Universitario Dr. Mario Muñoz Monroy , de Colón, provincia de Matanzas, en el período comprendido entre enero/1977 hasta diciembre/1999. Se presentaron 35 enfermos en los cuales se practicó una intervención quirúrgica por dicha patología (incidencia del 0,4 por ciento). La mayor frecuencia fue en el sexo masculino y en edades que fluctuaron entre los 5 y 73 años. La perforación, inflamación y la obstrucción del tránsito intestinal fueron las complicaciones más frecuentes del divertículo y que permitieron su diagnóstico durante laparotomías de urgencias en el 66 por ciento de los casos, en el 34 por ciento restante el diagnóstico se hizo como un hallazgo transoperatorio en el curso de laparotomías electivas por otras causas. La técnica quirúrgica más frecuentemente usada fue la diverticulectomía (77 por ciento). El estudio anátomo patológico de las piezas quirúrgicas demostraron mucosa heterotópica en el 40 por ciento de los casos. La evolución postoperatoria de todos los casos fue muy buena, no existiendo complicaciones inherentes al proceder realizado. El divertículo de Meckel es una entidad con la que el cirujano general se enfrenta con relativa frecuencia por lo que la actualización en el tema siempre resulta necesaria...(AU)
Assuntos
Humanos , Adulto , Divertículo Ileal/epidemiologia , Divertículo Ileal/cirurgiaRESUMO
The study of the Schistosoma mansoni genome, one of the etiologic agents of human schistosomiasis, is essential for a better understanding of the biology and development of this parasite. In order to get an overview of all S. mansoni catalogued gene sequences, we performed a clustering analysis of the parasite mRNA sequences available in public databases. This was made using softwares PHRAP and CAP3. The consensus sequences, generated after the alignment of cluster constituent sequences, allowed the identification by database homology searches of the most expressed genes in the worm. We analyzed these genes and looked for a correlation between their high expression and parasite metabolism and biology. We observed that the majority of these genes is related to the maintenance of basic cell functions, encoding genes whose products are related to the cytoskeleton, intracellular transport and energy metabolism. Evidences are presented here that genes for aerobic energy metabolism are expressed in all the developmental stages analyzed. Some of the most expressed genes could not be identified by homology searches and may have some specific functions in the parasite.
Assuntos
Perfilação da Expressão Gênica , RNA Mensageiro/genética , Schistosoma mansoni/genética , Schistosoma mansoni/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Análise por Conglomerados , Etiquetas de Sequências Expressas , Biblioteca Gênica , Genes de Helmintos , Estágios do Ciclo de Vida , Dados de Sequência Molecular , RNA Mensageiro/fisiologia , Schistosoma mansoni/crescimento & desenvolvimento , Transcrição GênicaRESUMO
The study of the Schistosoma mansoni genome, one of the etiologic agents of human schistosomiasis, is essential for a better understanding of the biology and development of this parasite. In order to get an overview of all S. mansoni catalogued gene sequences, we performed a clustering analysis of the parasite mRNA sequences available in public databases. This was made using softwares PHRAP and CAP3. The consensus sequences, generated after the alignment of cluster constituent sequences, allowed the identification by database homology searches of the most expressed genes in the worm. We analyzed these genes and looked for a correlation between their high expression and parasite metabolism and biology. We observed that the majority of these genes is related to the maintenance of basic cell functions, encoding genes whose products are related to the cytoskeleton, intracellular transport and energy metabolism. Evidences are presented here that genes for aerobic energy metabolism are expressed in all the developmental stages analyzed. Some of the most expressed genes could not be identified by homology searches and may have some specific functions in the parasite