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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Influ?ncia de fatores ambientais na incid?ncia do v?rus da infec??o hipodermal e necrose hematopoi?tica (IHHNV) no camar?o Litopenaeus vannamei cultivado em fazendas do Estado do Rio Grande do Norte (RN)

Silva, Cim?ria Porf?rio Rodrigues de Oliveira da 29 August 2008 (has links)
Made available in DSpace on 2014-12-17T14:10:17Z (GMT). No. of bitstreams: 1 CimariaPROS.pdf: 1137578 bytes, checksum: 6105cd049ff9ace294e10673c0d93fea (MD5) Previous issue date: 2008-08-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The shrimp farming industry is the most profitable area of the aquaculture at Rio Grande do Norte (RN) state, which is one of the largest producers in Brazil. However the infections that affect the shrimp cause major economic losses. The infection is a result of the interaction between the shrimp, the environment and pathogen. The change of these factors may lead to a condition of stress and susceptibility to opportunistic infections. One of these infections caused by Infectious Hypodermal and Hematopoietic Necrosis Virus (IHHNV) is widely distributed in several countries and affects a wide range of hosts. To optimize conditions for production of Litopenaeus vannamei shrimp, the more species cultivated in Brazil, it is necessary to understand the effects of environmental factors in the susceptibility of this species to infections. The aim of this study was to determine the IHHNV prevalence and to investigate the influence of environmental factors as salinity, temperature, stocking density, dissolved oxygen and rainfall in the IHHNV incidence in L. vannamei grown in farms, in the RN state. To determine the IHHNV prevalence were used 1089 samples of L. vannamei collected in seven farms. To perform the study about the influence of environmental factors, 525 samples of L. vannamei shrimp were collected in eight farms located in regions of low (0-1 ), medium (21-30 ) and high (38-57 ) salinity, using extensive (&#8804;15 shrimp/m2 ), semi-intensive (18-33 shrimp/m2) or intensive (>36 shrimp/m2) stocking density systems. The IHHNV infection was determined in pleopod and hemolymph using the polymerase chain reaction (PCR). The environmental factors were recorded during the collection of animals, using a refractometer to measure the salinity and a multi-parameter meter to measure the temperature and concentration of dissolved oxygen in the water. The IHHNV prevalence in RN was 43% (468 infected shrimp out of 1089), varying on different farms. On the seven farms studied, IHHNV prevalence ranged from 18.6% to 54.8%. The infection rates in the shrimp cultured in low, medium and high salinity were respectively 43.10% (125/290), 31.2% (15/48) and 24.6% (46/187) and was significantly higher in shrimp grown in low salinity (P<0.001). The infection rates in ponds of extensive, semi-intensive and intensive systems were respectively, 28.7%, 28.28% and 47.84%, and was significantly higher in high stocking densities (P<0.001). This study indicated a high IHHNV prevalence and a significant effect of salinity and stocking density, but not of the temperature, rainfall and dissolved oxygen on the IHHNV infection rate in the L. vannamei shrimp cultured in the northeastern Brazil / A carcinicultura ? a ?rea da aquicultura mais rent?vel do Rio Grande do Norte (RN), que ? um dos maiores produtores do Brasil. Por?m, as infec??es que acometem os camar?es v?m causando importantes perdas econ?micas. A infec??o ? resultado da intera??o entre o camar?o, o meio ambiente e o pat?geno. A altera??o desses fatores, pode levar a uma situa??o de estresse e suscetibilidade ? infec??es oportunistas. Uma dessas infec??es, causada pelo v?rus da Infec??o Hipodermal e Necrose Hematopoi?tica (IHHNV), encontra-se largamente distribu?da em v?rios pa?ses e apresenta uma grande variedade de hospedeiros. Para otimizar as condi??es de produ??o do camar?o de cultivo Litopenaeus vannamei, a esp?cie mais cultivada no Brasil, ? necess?rio compreender os efeitos dos fatores ambientais na suscetibilidade dessa esp?cie ?s infec??es. O presente estudo teve por objetivo determinar a preval?ncia do IHHNV e investigar a influ?ncia de fatores ambientais como a salinidade, temperatura, densidade de estocagem, oxig?nio dissolvido e pluviosidade na incid?ncia do IHHNV em fazendas de cultivo do L. vannamei, no estado do RN. Para determinar a preval?ncia do IHHNV foram utilizados 1089 amostras de L. vannamei coletados de sete fazendas. Para a realiza??o do estudo sobre a influ?ncia de fatores ambientais 525 amostras do camar?o L. vannamei foram coletadas em oito fazendas localizadas em regi?es de ?guas oligohalinas (0-1 ), mesohalinas (21-30 ) e hipersalinas (38-57 ), utilizando sistema de densidade de estocagem extensivo (&#8804;15 camar?es/m2), semi-intensivo (18-27 camar?es/m2) e intensivo (>30 camar?es/m2). A infec??o pelo IHHNV foi determinada em ple?podos e hemolinfa utilizando a rea??o da polimerase em cadeia (PCR). Os fatores ambientais foram registrados durante a coleta dos animais nos viveiros das fazendas, utilizando um refrat?metro para medir a salinidade e um medidor multi-par?metro para medir a temperatura e o oxig?nio dissolvido da ?gua. A preval?ncia do IHHNV no RN foi 43% (468 camar?es infectados de 1089), variando nas diferentes fazendas. Nas sete fazendas estudadas, a preval?ncia do IHHNV variou de 18,6% a 54,8%. As taxas de infec??o nas fazendas de ?guas oligohalinas, mesohalinas e hipersalinas foram respectivamente 43,10% (125/290), 31,2% (15/48) e 24,6% (46/187) e foi significativamente maior em camar?es cultivados em ?guas oligohalinas (P<0,001). As taxas de infec??o nos viveiros de sistema extensivo, semi-intensivo e intensivo foram respectivamente, 28,7%, 28,28% e 47,84% e foi significativamente maior em alta densidade de estocagem (P<0,001). Neste trabalho foi encontrado uma alta preval?ncia do IHHNV e um efeito significativo da salinidade e da densidade de estocagem, mas n?o da temperatura, pluviosidade e concentra??o do oxig?nio dissolvido sobre a taxa de infec??o pelo IHHNV no camar?o L. vannamei cultivado no Nordeste brasileiro
52

Aplicação de ensaio imunoenzimático para detecção de anticorpos contra o vírus respiratório sincicial em repectores de transplante de células tronco-hematopoéticas / Enzime-linked immunosorbent assay for detection of respiratory syncytial virus antibodies in hematopoietic stem cell transplant recipients

José de Paula Paz Junior 18 August 2008 (has links)
O vírus respiratório sincicial (RSV) é responsável por importante morbidade em receptores de transplante de células tronco-hematopoéticas (TCTH), especialmente no período que antecede a enxertia. A imunidade induzida pela infecção pelo RSV é transitória e as reinfecções são freqüentes. O comportamento e papel dos anticorpos anti-RSV em receptores de TCTH é desconhecido. Em amostras de soro estocadas, ensaio imunoenzimático (ELISA) foi aplicado para detecção de anticorpos anti-RSV para avaliar a dinâmica desses anticorpos antes e após o TCTH, em pacientes com e sem infecção pelo RSV, bem como a resposta de anticorpos específicos nos pacientes com infecção pelo RSV diagnosticada por imunofluorescência direta. A mediana do tempo de coleta das amostras pré-TCTH foi de -35 e -44 dias nos casos e controles, respectivamente, com média de títulos de anticorpos anti-RSV de 2490 UA/mL e 2872 UA/mL, respectivamente. Após o transplante, as medianas de tempo das 3 amostras analisadas dos pacientes com infecção pelo RSV foram d+14, d+52 e d+89 e os respectivos títulos de anticorpos foram 2457 UA/mL, 2715 UA/mL e 2950 UA/mL. Nos pacientes sem infecção pelo RSV (controles), as medianas de tempo das 3 amostras analisadas foram d+9, d+69 e d+93 e os respectivos títulos de anticorpos foram 2738 UA/mL, 2794 UA/mL e 2642 UA/mL. Não houve diferença estatística entre os dois grupos. Nenhum dos pacientes com infecção pelo RSV apresentou elevação de quatro vezes nos títulos de anticorpos / Respiratory syncytial virus (RSV) infection can cause significant morbidity and mortality in haematopoietic stem cell transplant (HSCT) recipients, especially when upper respiratory tract infection (RTI) progresses to lower RTI, which is expected to occur in more than 50% of the patients. The humoral immunity induced by RSV infection is transient and reinfections are frequent. The dynamics and role of anti-RSV antibodies in HSCT recipients are unknown. In stored serum samples, an enzyme-linked immunosorbent assay (EIA) was applied to evaluate the dynamics of anti-RSV antibodies in HSCT recipients with and without RSV infection, as well as the specific humoral response in HSCT recipients with RSV infection diagnosed by direct immunofluorescent assay in nasal wash samples. Pre-transplant samples were selected at a median time of 35 and 44 days and the mean concentration of RSV antibodies were 2490 AU/mL and 2872 AU/mL, in cases and controls, respectively. After HSCT, serum samples from patients with RSV infection (cases) were evaluated at median time of 14, 52 and 89 days, and the respective mean concentrations of anti- RSV antibodies were 2457 AU/mL, 2715 AU/mL and 2950 AU/mL. In patients without RSV (controls), serum samples were evaluated at median time of 9, 69 and 93 days, and the respective mean concentrations of anti-RSV antibodies were 2738 AU/mL, 2794 AU/mL e 2642 AU/mL. Difference was not statistically significant. No patient developed a four-fold rise in RSV antibody titers
53

Lentiviral vector mediated haematopoietic stem cell gene therapy for mucopolysaccharidosis type IIIA

Langford-Smith, Alexander William Walker January 2012 (has links)
Mucopolysaccharidosis type III (Sanfilippo) is comprised of four phenotypically similar lysosomal storage disorders (MPS IIIA-D) caused by the deficiency of enzymes that catabolise heparan sulphate (HS). Progressive accumulation of HS results in abnormal behaviour, progressive cognitive and motor impairment and death in mid-teens. There are currently no treatments for MPS III. To assess the effect of novel therapeutics in the mouse models of MPS III it is necessary to examine the effect on primary storage of HS, secondary storage and behaviour. The reported behaviour of MPS IIIA and B mice is conflicting therefore we developed a one-hour open field test, performed at the same time of day during a period of hyperactivity observed in a previous circadian rhythm study of MPS IIIB mice. At 8 months of age MPS IIIB mice were hyperactive, with increased rapid exploratory behaviour and a reduction in immobility time. The MPS IIIA mice presented with the same behavioural phenotype as the MPS IIIB mice and were significantly hyperactive at 4 and 6 months of age and also displayed a reduced sense of danger. The hyperactivity and reduced sense of danger observed in the mice is consistent with the patient phenotype. Whilst haematopoietic stem cell transplant (HSCT) is the standard therapy used to treat the similar HS storage disorder MPS I Hurler, it is ineffectual in MPS IIIA. We hypothesise that HSCT failure in MPS IIIA is due to insufficient enzyme production in the brain by donor-derived microglial cells. By increasing expression of N-sulphoglucosamine sulphohydrolase (SGSH) we may be able to treat MPS IIIA. Therefore we compared the effect of HSCT using normal haematopoietic stem cells (WT-HSCT) to lentiviral overexpression of SGSH in normal cells (LV-WT-HSCT) or MPS IIIA cells (LV-IIIA-HSCT) in MPS IIIA mice, using the behavioural tests developed.SGSH activity in the brain of MPS IIIA recipients was not significantly increased by WT-HSCT, but was significantly increased by LV-IIIA-HSCT and LV-WT-HSCT. HS was significantly reduced by all transplants but the best treatment was LV-WT-HSCT. Neuroinflammation, indicated by the number of microglia in the brain, was significantly reduced by all treatments but remains significantly elevated. GM2 gangliosides were significantly reduced by WT-HSCT and LV-WT-HSCT and were no longer significantly elevated, but LV-IIIA-HSCT had no significant effect. Critically LV-WT-HSCT corrected the behaviour at 4 and 6 months of age whilst the other treatments had no significant effect. LV-WT-HSCT and WT-HSCT reduced GM2 gangliosides and neuroinflammation equally but only LV-WT-HSCT corrected behaviour and primary HS storage, suggesting they are the important factors in MPS IIIA pathology. LV-WT-HSCT corrects the neurological phenotype in MPS IIIA mice and is a clinically viable approach to treat MPS IIIA and other neuropathic lysosomal storage disorders.

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