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Id: biblio-2314
Autor: Garcia, Charlene Silvestrin Celi; Garcia, Luiz Carlos Celi; Henriques, João Antonio Pêgas; Ely, Mariana Roesch; Garcia, Paulo Miguel Celi.
Título: Enxerto autólogo de células-tronco derivadas do tecido adiposo: uma nova visão de sua aplicação no tratamento de queimados e na cirurgia plástica reparadora / Adipose tissue-derived stem cell autologous grafts: a new approach to application in the treatment of burn victims and reconstructive plastic surgery
Fonte: Rev. bras. cir. plást;31(3):417-423, 2016. ilus, tab.
Idioma: en; pt.
Resumo: No Brasil, 1 milhão de acidentes com queimaduras acontecem por ano e as infecções são responsáveis por 75% dos óbitos nestes pacientes, além de deixar lesões que ocasionam deformidades nas áreas atingidas. Sendo assim, o objetivo deste trabalho é fornecer uma visão atual sobre células-tronco mesenquimais (MSCs), com ênfase nas células-tronco derivadas do tecido adiposo (ADSCs), associadas a gel de plasma, gel de fibrina e membranas (scaffold). O uso de géis e membranas tendem a auxiliar o crescimento celular visando sua possível aplicação na Cirurgia Plástica Reparadora para o tratamento pacientes queimados ou que necessitam de enxerto de pele. O presente trabalho abordou de forma exploratória e narrativa o tema células-tronco mesenquimais, células-tronco mesenquimais derivadas do tecido adiposo, gel de fibrina, gel de plasma e scaffold. O tipo de pesquisa empregada foi conduzido com coleta de informações utilizando-se a Biblioteca Virtual em Saúde (BVS) e PubMed. O número absoluto de artigos publicados relacionados ao tratamento de queimaduras é considerável. Até o momento, a quantidade de pesquisas relacionadas à terapia com células-tronco derivadas do tecido adiposo, gel de fibrina, gel de plasma e scaffold para o tratamento de queimaduras apresenta-se escassa. O autoenxerto de ADSCs associado a biocurativos torna-se uma perspectiva promissora na Cirurgia Plástica Reparadora para o tratamento e recuperação de pacientes que sofreram queimaduras ou outros acidentes que necessitam de enxerto de pele. Estes recursos podem reduzir a dor e prover a dessecação da lesão, promovendo neovascularização e a reepitelização da ferida.

In Brazil, 1 million burn accidents occur annually, and subsequent wound infections account for 75% cases of deaths among these patients, in addition to inducing deformities in the affected areas. Therefore, the aim of this study was to discuss the current status of mesenchymal stem cells, with an emphasis on adipose-derived stem cells (ADSCs), in combination with plasma gel, glue fibrin, and membranes (scaffold). The use of gels and membranes supports cell growth, and aims at potential application in reconstructive plastic surgery for the treatment of burn patients or individuals requiring skin grafts. This study explores and discusses the role of mesenchymal stem cells, adipose-derived mesenchymal stem cells, glue fibrin, plasma gel, and the scaffold. This research collected information from the Virtual Health Library (VHL) and PubMed. A considerable number of articles have been published on burn treatment. However, there is little research on burn treatment with ADSCs, glue fibrin, plasma gel, and scaffold. An ADSC autograft combined with a biological dressing is promising in reconstructive plastic surgery for the treatment and recovery of burn patients or individuals with other injuries that require skin grafts. These features can reduce pain and aid in drying of the lesion, thus promoting neovascularization and wound reepithelialization.
Descritores: Pele
Transplante Autólogo
Bioprótese
Queimaduras
Membrana Celular
Revisão
Procedimentos Cirúrgicos Reconstrutivos
Células-Tronco Mesenquimais
Géis
-Pele/lesões
Transplante Autólogo/métodos
Bioprótese/efeitos adversos
Bioprótese/normas
Queimaduras/cirurgia
Queimaduras/complicações
Membrana Celular/patologia
Membrana Celular/transplante
Tecido Adiposo
Tecido Adiposo/cirurgia
Tecido Adiposo/lesões
Procedimentos Cirúrgicos Reconstrutivos/métodos
Células-Tronco Mesenquimais/patologia
Géis/efeitos adversos
Géis/uso terapêutico
Neovascularização Patológica
Neovascularização Patológica/cirurgia
Neovascularização Patológica/patologia
Neovascularização Patológica/terapia
Limites: Humanos
História do Século XXI
Tipo de Publ: Revisão
Responsável: BR32.1 - Serviço de Biblioteca e Informação Biomédica


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Id: lil-780828
Autor: Mohamed, Yasmine Fathy; Abou-Shleib, Hamida Moustafa; Khalil, Amal Mohamed; El-Guink, Nadia Mohamed; El-Nakeeb, Moustafa Ahmed.
Título: Membrane permeabilization of colistin toward pan-drug resistant Gram-negative isolates
Fonte: Braz. j. microbiol;47(2):381-388, Apr.-June 2016. tab, graf.
Idioma: en.
Resumo: Abstract Pan-drug resistant Gram-negative bacteria, being resistant to most available antibiotics, represent a huge threat to the medical community. Colistin is considered the last therapeutic option for patients in hospital settings. Thus, we were concerned in this study to demonstrate the membrane permeabilizing activity of colistin focusing on investigating its efficiency toward those pan-drug resistant isolates which represent a critical situation. We determined the killing dynamics of colistin against pan-drug resistant isolates. The permeability alteration was confirmed by different techniques as: leakage, electron microscopy and construction of an artificial membrane model; liposomes. Moreover, selectivity of colistin against microbial cells was also elucidated. Colistin was proved to be rapid bactericidal against pan-drug resistant isolates. It interacts with the outer bacterial membrane leading to deformation of its outline, pore formation, leakage of internal contents, cell lysis and finally death. Furthermore, variations in membrane composition of eukaryotic and microbial cells provide a key for colistin selectivity toward bacterial cells. Colistin selectively alters membrane permeability of pan-drug resistant isolates which leads to cell lysis. Colistin was proved to be an efficient last line treatment for pan-drug resistant infections which are hard to treat.
Descritores: Membrana Celular/metabolismo
Infecções por Bactérias Gram-Negativas/microbiologia
Colistina/metabolismo
Farmacorresistência Bacteriana Múltipla
Bactérias Gram-Negativas/metabolismo
Antibacterianos/metabolismo
-Testes de Sensibilidade Microbiana
Membrana Celular/efeitos dos fármacos
Permeabilidade da Membrana Celular
Infecções por Bactérias Gram-Negativas/tratamento farmacológico
Colistina/farmacologia
Bactérias Gram-Negativas/isolamento & purificação
Bactérias Gram-Negativas/efeitos dos fármacos
Bactérias Gram-Negativas/ultraestrutura
Antibacterianos/farmacologia
Limites: Humanos
Responsável: BR1.1 - BIREME


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Id: biblio-839372
Autor: Mejía-Barajas, Jorge A; Montoya-Pérez, Rocío; Salgado-Garciglia, Rafael; Aguilera-Aguirre, Leopoldo; Cortés-Rojo, Christian; Mejía-Zepeda, Ricardo; Arellano-Plaza, Melchor; Saavedra-Molina, Alfredo.
Título: Oxidative stress and antioxidant response in a thermotolerant yeast
Fonte: Braz. j. microbiol;48(2):326-332, April.-June 2017. tab, graf.
Idioma: en.
Resumo: Abstract Stress tolerance is a key attribute that must be considered when using yeast cells for industrial applications. High temperature is one factor that can cause stress in yeast. High environmental temperature in particular may exert a natural selection pressure to evolve yeasts into thermotolerant strains. In the present study, three yeasts (Saccharomyces cerevisiae, MC4, and Kluyveromyces marxianus, OFF1 and SLP1) isolated from hot environments were exposed to increased temperatures and were then compared with a laboratory yeast strain. Their resistance to high temperature, oxidative stress, and antioxidant response were evaluated, along with the fatty acid composition of their cell membranes. The SLP1 strain showed a higher specific growth rate, biomass yield, and biomass volumetric productivity while also showing lower duplication time, reactive oxygen species (ROS) production, and lipid peroxidation. In addition, the SLP1 strain demonstrated more catalase activity after temperature was increased, and this strain also showed membranes enriched in saturated fatty acids. It is concluded that the SLP1 yeast strain is a thermotolerant yeast with less oxidative stress and a greater antioxidant response. Therefore, this strain could be used for fermentation at high temperatures.
Descritores: Saccharomyces cerevisiae/fisiologia
Estresse Fisiológico
Kluyveromyces/fisiologia
Estresse Oxidativo
Antioxidantes/metabolismo
-Saccharomyces cerevisiae/crescimento & desenvolvimento
Saccharomyces cerevisiae/efeitos da radiação
Saccharomyces cerevisiae/química
Kluyveromyces/crescimento & desenvolvimento
Kluyveromyces/efeitos da radiação
Kluyveromyces/química
Peroxidação de Lipídeos
Catalase/análise
Membrana Celular/química
Espécies Reativas de Oxigênio/metabolismo
Biomassa
Ácidos Graxos/análise
Temperatura Alta
Responsável: BR1.1 - BIREME


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Id: lil-504112
Autor: Shohael, Abdullah Mohammad; Murthy, Hosakatte Niranjana; Hahn, Eun-Joo; Paek, Kee-Yoeup.
Título: Methyl jasmonate induced overproduction of eleutherosides in somatic embryos of Eleutherococcus senticosus cultured in bioreactors
Fonte: Electron. j. biotechnol;10(4):633-637, oct. 2007. tab.
Idioma: en.
Projeto: Ministry of Education and Human Resources Development; . Ministry of Commerce, Industry and Energy; . Ministry of Labor; . Korean Federation of Science and Technology Societies. Brain Pool Fellowship.
Resumo: This study was concentrated on the production of eleutherosides and chlorogenic acid in embryogenic suspension cultures of Eleutherococcus senticosus by exposing them to different concentrations (50-400 µM) of methyl jasmonate (MJ) during the culture period. In the bioreactor cultures, eleutheroside content increased significantly by elicitation of MJ, however, the fresh weight, dry weight and growth ratio of embryos was strongly inhibited by increasing MJ concentrations. The highest total eleutheroside (7.3 fold increment) and chlorogenic acid (3.9 fold increment) yield was obtained with 200 µM MJ treatment. There was 1.4, 3.4 and 14.9 fold increase in the eleutheroside B, E, and E1 production respectively with such elicitation treatment. These results suggest that MJ elicitation is beneficial for eleutheroside accumulation in the embryogenic cell suspension cultures.
Descritores: Eleutherococcus/metabolismo
Extratos Vegetais/análise
Reatores Biológicos
Reguladores de Crescimento de Planta/metabolismo
-Eleutherococcus/citologia
Eleutherococcus/embriologia
Membrana Celular/metabolismo
Técnicas de Cultura de Células
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-912695
Autor: López Armengol, María Fernanda; Rubio, Natalia; Sabino, Guillermo Ariel; Bérgamo, Nadia Soledad; Pelufo, Valeria.
Título: Microscopic sperm head damage and abnormalities as heat stress indicators in Australian Merino rams (Ovis aries) in Northern Patagonia, Argentina / Danos e anormalidades microscópicas das cabeças espermáticas como indicadores de estresse por calor em carneiros Merino Australiano (Ovis aries) da Patagônia Norte, Argentina
Fonte: Braz. J. Vet. Res. Anim. Sci. (Online);55(1):1-11, 2 abr. 2018. ilus, tab, graf.
Idioma: en.
Projeto: Universidad Nacional del Comahue.
Resumo: In Northern Patagonia, the mating season starts on March 15th, when rams are submitted to summer temperatures. Exposure of rams to heat stress increases the prevalence of microscopic damage to spermatozoa, morphological abnormalities, and reductions in fertility. This study assesses the adaptive capabilities of six unshorn and six shorn Australian Merino rams, half of which were treated in a heat chamber for eight hours for five days, gradually reaching a temperature of up to 40 °C. Microscopic damage, abnormalities and ultramicroscopic alterations of the plasma membrane and the acrosome of sperm head were analysed. There were significant differences in the percentage of tailless spermatozoa and proximal cytoplasmic droplets between post-treatment periods. Temperature primarily affected the shorn rams and the sperm heads during spermiogenesis. Submicroscopic alterations were observed when the plasma membrane was present in the anterior segment. These alterations can be intact, waved, or dilated. When the plasma membrane was absent, the acrosome might be intact, dilated, and waved. In addition, the outer acrosomal membrane may completely lose its contents or have a nude nucleus. The plasma membrane assumes a waved shape as a result of the effect of temperature on the epididymis. According to this study, the tailless head, proximal cytoplasmic droplets, and the ultramicroscopic categories studied were robust indicators of semen heat stress. After ten weeks, the sperm head recovered its normal shape. Unshorn rams are better adapted to summer heat stress than shorn ones. Microscopy and transmission electron microscopy alterations have been shown to be excellent indicators of thermal stress in Australian Merino rams and may be useful tools to help sheep farmers choose when to begin the mating season, which will vary depending on the environmental conditions of the summer.(AU)

Na Patagônia Norte, os ovinos têm sua estação de acasalamento iniciada em 15 de março, portanto, ficam sujeitos às temperaturas do verão. A exposição de carneiros a estresse térmico aumenta a prevalência de danos microscópicos e anomalias morfológicas nos espermatozoides, que implica uma redução na fertilidade. Este trabalho avaliou a capacidade adaptativa de carneiros Merino Australiano com lã (N = 6) e tosquiados (N = 6): metade ficou ao ar livre e outra metade foi mantida em uma câmara climática por oito horas, durante cinco dias, chegando gradualmente a uma temperatura máxima de 40 °C. Foram analisados danos microscópicos, anormalidades e alterações ultramicroscópicas da membrana plasmática e do acrossoma da cabeça dos espermatozoides. Os resultados microscópicos confirmaram a existência de diferença significativa na porcentagem de espermatozoides sem cauda e com gota citoplasmática proximal, entre os ejaculados pós-tratamento. A temperatura afetou os carneiros tosquiados, principalmente a cabeça de seus espermatozoides, durante a espermatogênese. Alterações submicroscópicas foram observados na membrana plasmática quando ela estava presente no segmento anterior: quando não intacta, ficava ondulada ou dilatada. Quando a membrana plasmática estava ausente, o acrossoma podia se apresentar ondulado ou dilatado. Além disso, sob efeito do calor, a membrana acrossomal externa pode perder completamente seu conteúdo ou apresentar núcleo desnudo. A membrana plasmática assume uma forma ondulada pelo efeito da temperatura no epidídimo. Depois de dez semanas, a cabeça dos espermatozoides recuperou sua forma normal. Como demonstrado neste estudo, a cabeça sem cauda, as gotas citoplasmáticas proximais e as categorias ultramicroscópicas estudadas são indicadores do efeito do estresse térmico no sêmen, e os carneiros com maior cobertura de lã se adaptam melhor ao estresse por calor. Alterações de microscopia e de microscopia eletrônica de transmissão têm se mostrado excelentes indicadores de estresse por calor em carneiros Merino Australiano e podem ser ferramentas úteis para ajudar criadores de ovelhas a escolher quando começar a época de acasalamento, o que irá variar de acordo com as condições ambientais do verão.(AU)
Descritores: Cabeça do Espermatozoide/ultraestrutura
Acrossomo/ultraestrutura
Ovinos/fisiologia
Membrana Celular/ultraestrutura
Transtornos de Estresse por Calor/complicações
Teratozoospermia/diagnóstico por imagem
-Argentina
Cauda do Espermatozoide/ultraestrutura
Espermatogênese
Limites: Animais
Masculino
Responsável: BR68.1 - Biblioteca Virginie Buff D'Ápice


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Id: biblio-894938
Autor: Agustinho, Daniel P; Miller, Liza C; Li, Lucy X; Doering, Tamara L.
Título: Peeling the onion: the outer layers of Cryptococcus neoformans
Fonte: Mem. Inst. Oswaldo Cruz;113(7):e180040, 2018. graf.
Idioma: en.
Projeto: NIH.
Resumo: Cryptococcus neoformans is an opportunistic fungal pathogen that is ubiquitous in the environment. It causes a deadly meningitis that is responsible for over 180,000 deaths worldwide each year, including 15% of all AIDS-related deaths. The high mortality rates for this infection, even with treatment, suggest a need for improved therapy. Unique characteristics of C. neoformans may suggest directions for drug discovery. These include features of three structures that surround the cell: the plasma membrane, the cell wall around it, and the outermost polysaccharide capsule. We review current knowledge of the fundamental biology of these fascinating structures and highlight open questions in the field, with the goal of stimulating further investigation that will advance basic knowledge and human health.
Descritores: Polissacarídeos
Cryptococcus neoformans
-Membrana Celular
Parede Celular
Limites: Humanos
Responsável: BR1.1 - BIREME


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Id: biblio-893117
Autor: Troncoso, Claudia; Pavez, Mónica; Santos, Andrés; Salazar, Rodrigo; Barrientos, Leticia.
Título: Implicancias estructurales y fisiológicas de la célula bacteriana en los mecanismos de resistencia antibiótica / Structural and physiological implications of bacterial cell in antibiotic resistance mechanisms
Fonte: Int. j. morphol;35(4):1214-1223, Dec. 2017. graf.
Idioma: es.
Projeto: Conicyt.
Resumo: RESUMEN: La alta capacidad de adaptación de las bacterias a ambientes hostiles ha permitido el desarrollo de resistencia a antibacterianos, causando problemas de impacto mundial en la salud hospitalaria y de la comunidad, limitando las opciones terapéuticas lo que afecta el control de enfermedades, elevando las tasas de morbi-mortalidad. Esta capacidad de resistencia es mediada por factores estructurales y fisiológicos de las bacterias que actúan a diferentes niveles tanto extracelular como intracelular. A niveles extracelulares se destaca la capacidad de las poblaciones bacterianas en la formación de biopelículas y la regulación de señales celulares quorum sensing, permitiendo la evasión de la acción antibiótica. A nivel de envoltura celular se destaca el funcionamiento y comportamiento de la pared celular y de la membrana celular, principalmente por medio de la regulación de la expresión de canales de entrada o porinas y/ o bombas de expulsión que impiden el acceso o inducen la salida de antibióticos; otros mecanismos integran la modificación de la actividad de drogas por medio de la hidrólisis o modificación del sitio activo del fármaco. A nivel intracelular, las bacterias pueden cambiar los procesos de óxido/reducción, modificar los sitios objetivos del antibiótico e inactivar los grupos transfer, y modificar las subunidades ribosomales afectando la acción de los antibióticos que inhiben la síntesis de proteínas. A esto se añaden las modificaciones en la expresión génica y del código genético, que regula todos los anteriores, y es capaz de generar cambios adaptativos, resistencia a fármacos y desinfectantes, entre otros. La presente revisión tiene como objetivo describir las implicancias estructurales y fisiológicas de la célula bacteriana en los mecanismos de resistencia antibiótica considerando la organización estructural y fisiológica involucrada en los principales mecanismos de resistencia a antibióticos presentes en bacterias de importancia clínica que conllevan a fallas terapéuticas con alto costo en salud humana.

SUMMARY: The high adaptability of bacteria to hostile environments has favored antibacterial resistance development, impacting hospital and community healthcare worldwide. It has also affected disease control, limited therapeutic options and raised morbiditymortality rate. This resistance ability is mediated by structural and physiological factors of bacteria acting at both extracellular and cellular levels. The ability of bacterial populations in biofilm formation and regulation of cellular signal quorum sensing at the extracellular level, allows for the evasion of antibiotic action. At a cellular level, the performance and behavior of the cell wall and cell membrane is emphasized, mainly by regulating the expression of inlet channels or porins and/or expulsion pumps preventing access to, or inducing the outflow of antibiotics. Other mechanisms integrate modification of drug activity by hydrolysis or modification of the active site of the drug. Further into intracellular level, bacteria can change the oxidation/reduction processes; modify the target sites of the antibiotic and inactivate transfer groups. Bacteria can also modify the ribosomal subunits affecting the antibiotics which inhibit protein synthesis, and cause modifications of gene expression and genetic code that regulate the above mechanism. These may also generate adaptive changes and resistance to drugs and disinfectants. The aim of the present review is to describe the structural and physiological implications of bacterial cell in the mechanisms of antibiotic resistance. The study also considered the structural and physiological organization involved in the main mechanisms of antibiotic resistance in bacteria relevant to clinical healthcare.
Descritores: Membrana Celular/fisiologia
Farmacorresistência Bacteriana/fisiologia
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-889442
Autor: Garcia, Israel José Pereira; Cézar, Jessica Silva; Lemos, Bruno Silva; Silva, Lilian Nayra; Ribeiro, Rosy Iara Maciel de Azambuja; Santana, Camilla Camerino; Grillo, Luciano Aparecido Meireles; Pinto, Flavia Carmo Horta; Buzelle, Samyra Lopes; Cortes, Vanessa Faria; Santos, Hérica de Lima; Santos, Maria Emilia Soares Martins dos; Barbosa, Leandro Augusto.
Título: Effects of high fat diet on kidney lipid content and the Na, K-ATPase activity
Fonte: Braz. J. Pharm. Sci. (Online);54(1):e17165, 2018. tab, graf, ilus.
Idioma: en.
Projeto: Fundação de Amparo a Pesquisa do Estado de Minas Gerais; . Coordenação de Aperfeiçoamento de Pessoal de Nível Superior; . Conselho Nacional de Desenvolvimento Científico e Tecnológico.
Resumo: ABSTRACT It is widely known that high fat diet (HFD) can contribute to the advent of health problems. Recent studies have indicated that obesity imposes a hemodynamic overload to the kidneys. In order to further investigate such injuries, two groups of six Swiss mice each were fed with a controlled AIN93G diet or a high fat (AIN93G modified) diet for eight weeks. Blood samples were collected to determine the hormonal, lipid profile, glucose, urea, and creatinine levels. Histopathological and immunohistochemical analysis were carried out to analysis the kidney damage. Fractions of renal membranes were prepared to assess the Na,K-ATPase activity, lipid peroxidation, total cholesterol, and phospholipid content. The results indicated that the blood lipid profile, urea and creatinine was not altered by the HFD. On the other hand, it was observed in HFD diet mice elevated glucose blood levels along with an augment on insulin and a decrease on corticosterone release. HFD provoked a reduction in the diameter of the convoluted tubules and cell volume in Bowman's capsule and an increased number of positive cells with Na,K-ATPase, but reduced the Na,K-ATPase activity and the cholesterol content in the kidney cell membrane but favored the lipid peroxidation.
Descritores: Sódio/análise
ATPase Trocadora de Hidrogênio-Potássio/análise
Dieta Hiperlipídica/efeitos adversos
-Imuno-Histoquímica/métodos
Membrana Celular
Análise Estatística
Insuficiência Renal/fisiopatologia
Rim/fisiopatologia
Limites: Animais
Masculino
Camundongos
Responsável: BR40.1 - DBD - Divisão de Biblioteca e Documentacão do Conjunto das Químicas


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Id: biblio-955111
Autor: Mello, Thaís Pereira de; Aor, Ana Carolina; Gonçalves, Diego de Souza; Seabra, Sergio Henrique; Branquinha, Marta Helena; Santos, André Luis Souza dos.
Título: Scedosporium apiospermum, Scedosporium aurantiacum, Scedosporium minutisporum and Lomentospora prolificans: a comparative study of surface molecules produced by conidial and germinated conidial cells
Fonte: Mem. Inst. Oswaldo Cruz;113(6):e180102, 2018. tab, graf.
Idioma: en.
Resumo: BACKGROUND Scedosporium/Lomentospora species are opportunistic mould pathogens, presenting notable antifungal resistance. OBJECTIVES/METHODS We analysed the conidia and germinated conidia of S. apiospermum (Sap), S. aurantiacum (Sau), S. minutisporum (Smi) and L. prolificans (Lpr) by scanning electron microscopy and exposition of surface molecules by fluorescence microscopy. FINDINGS Conidia of Sap, Smi and Sau had oval, ellipsoidal and cylindrical shape, respectively, with several irregularities surrounding all surface areas, whereas Lpr conidia were rounded with a smooth surface. The germination of Sap occurred at the conidial bottom, while Smi and Sau germination primarily occurred at the centre of the conidial cell, and Lpr germination initiated at any part of the conidial surface. The staining of N-acetylglucosamine-containing molecules by fluorescein-labelled WGA primarily occurred during the germination of all studied fungi and in the conidial scars, which is the primary location of germination. Calcofluor white, which recognises the polysaccharide chitin, strongly stained the conidial cells and, to a lesser extent, the germination. Both mannose-rich glycoconjugates (evidenced by fluoresceinated-ConA) and cell wall externally located polypeptides presented distinct surface locations and expression according to both morphotypes and fungal species. In contrast, sialic acid and galactose-containing structures were not detected at fungal surfaces. MAIN CONCLUSIONS The present study demonstrated the differential production/exposition of surface molecules on distinct morphotypes of Scedosporium/Lomentospora species.
Descritores: Esporos Fúngicos/fisiologia
Membrana Celular/ultraestrutura
Scedosporium/crescimento & desenvolvimento
-Microscopia Eletrônica de Varredura
Diferenciação Celular
Microscopia de Fluorescência
Limites: Humanos
Responsável: BR1.1 - BIREME


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Id: lil-714336
Autor: Cabrera, Paulina; Sánchez, Raúl; Risopatrón, Jennie.
Título: Selección espermática en semen congelado/descongelado de equino: evaluación de las membranas plasmática, acrosomal y potencial de membrana mitocondrial / Sperm selection in frozen/thawed semen of equine: evaluation of plasma, acrosome membranes and mitochondrial membrane potential
Fonte: Int. j. morphol;32(2):725-731, jun. 2014. ilus.
Idioma: es.
Resumo: Los procedimientos de criopreservación inducen cambios morfofuncionales en los espermatozoides. Es importante post descongelación espermática utilizar procedimientos de selección que permitan recuperar espermatozoides altamente funcionales. El objetivo del presente estudio fue comparar la eficiencia del Swim-up y Equipure® en la selección de espermatozoides funcionales en semen descongelado de equino. Semen de 4 potros reproductores Criollos Chilenos (A, B, C y D), fueron descongelados separadamente y procesados (n=15) por: I.- Swim-up (SU) y II.- Equipure® (EQ). Post descongelación se determinó por citometría de flujo la viabilidad e integridad de membrana plasmática (SYBR-14/PI), potencial de membrana mitocondrial (YDm; JC-1), integridad de la membrana acrosomal (FITC-PSA/PI). La motilidad progresiva (%) en dos animales fue más alta (P<0,05) por SU comparado con EQ: A (55,7±5,8% v/s 38,17±3,7%) y C (37,5±7% vs. 32±2,1%, respectivamente). La integridad de la membrana plasmática (%), tres animales presentaron diferencias (P<0,05), siendo más alta por SU en dos animales comparado con EQ (A: 54,3±1,7 vs. 36,7±1,9, C: 36,1±5,7 vs. 29,4±4,8 y D: 34,4±9,4 vs. 52,7±5,2; respectivamente), solamente un animal fue superior EQ. En el YDm (%), diferencias significativas (P<0,05) fueron detectadas en los cuatro animales, siendo más altos en SU comparado con EQ (A: 69,1±8,6% vs. 47,4±3,3%, B: 59,34±12,3% vs. 24,8±1,5%, C: 54,9±12,3% vs. 43,2±3,1% y D: 53,1±17,6% vs. 37,5±5,7%; respectivamente). Los resultados obtenidos en el presente estudio demostraron que los métodos de selección espermática Swim-up y Equipure® permiten recuperar espermatozoides de diferente calidad funcional en semen congelado-descongelado de equino, presentándose diferencias individuales entre los animales con respecto a los métodos. Se observó una tendencia del método Swim-up en seleccionar espermatozoides de equino descongelados con mayor calidad funcional comparado con Equipure®.

Freeze-thaw procedures induce structural and functional changes in sperm. It is important to use post thaw sperm selection procedures that can retrieve highly functional sperm. The aim of this study was to compare the efficiency of the Swim-up and Equipure® in the selection of functional sperm of thawed equine semen. Semen of four Chilean Criollo reproductive stallions (A, B , C and D) were frozen and thawed using a standard protocol and processed separately (n = 15) : I. Swim-up (SU) and II. Equipure® (EQ). Post sperm selection,was determined by flow cytometry. Viability and plasma membrane integrity (SYRB-14/PI), mitochondrial membrane potential (YDm, JC -1), acrosome membrane integrity (FITC-PSA/PI). Progressive motility (%) was higher (P<0.05) in two animals per SU compared with EQ, A (55.7±5.8% vs. 38.17±3.7%) and C (37.5±7.0% vs. 32±2.1%, respectively). The viability and integrity of the plasma membrane (%), three animals showed differences (P<0.05), being higher for SU in two animals compared with EQ (A: 54.3±1.7 vs. 36.7±1.9, C: 36.1±5.7 vs. 29.4±4.8 and D: 34.4±9.4 vs. 52.7±5.2, respectively), only one animal was higher EQ. In YDm (%), significant differences were detected (P<0.05) in all four animals, being higher in SU compared with EQ (A: 69.1±8.6% vs. 47.4±3.3% B: 59.34±12.3% vs. 24.8±1.5%, C: 54.9±12.3% vs. 43.2±3.1% and D: 53.1±17.6% vs. 37.5±5.7%, respectively). The results obtained in this study showed that sperm selection methods Swim-up and Equipure® can retrieve different functional sperm quality in frozen-thawed equine semen, and that individual differences were registered among animals with respect to methods. In the Swim-up method a tendency for selecting higher functional quality in thawed equine sperm was observed when compared to Equipure®.
Descritores: Espermatozoides/fisiologia
Criopreservação/veterinária
Cavalos
-Preservação do Sêmen
Motilidade Espermática/fisiologia
Acrossomo/fisiologia
Membrana Celular/fisiologia
Potencial da Membrana Mitocondrial/fisiologia
Análise do Sêmen
Citometria de Fluxo
Limites: Animais
Masculino
Responsável: CL1.1 - Biblioteca Central



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