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1.
Mol Biochem Parasitol ; 225: 73-83, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30179636

RESUMO

Helminths are complex pathogens that ensure their long-term survival by influencing the immune responses of their host. Excretory/secretory products (ESP) can exert immunoregulatory effects which foster parasite survival. Galectins represent a widespread group of ß-galactoside-binding proteins which are involved in a multitude of biological processes operative in parasite-host interaction. We had earlier identified seven galectins in Strongyloides ratti, four of them detected in the ESP of distinct developmental stages of the parasite. In the present report, we focused on the characterization of two of them, Sr-galectin-1 (Sr-Gal-1) and Sr-galectin-3 (Sr-Gal-3). While Sr-Gal-3 expression was strongest in parasitic females, Sr-Gal-1 was predominantly expressed in free-living females. Both proteins were cloned and recombinantly expressed in an E. coli expression system. Their glycan-binding activity was verified by haemagglutination and glycan array analysis. Furthermore, primary immunological activities of the Sr-galectins were initially investigated by the application of an in vitro mucosal 3D-culture model, comprising of mucosa-associated epithelial and dendritic cells. The Sr-galectins stimulated preferentially the release of the type 2 cytokines thymic stromal lymphopoietin and IL-22, a first indication for immunoregulatory activity. In addition, the Sr-galectins dose-dependently fostered cell migration. Our results confirm the importance of these carbohydrate-binding proteins in host-parasite-interaction by indicating possible interaction with the host mucosa-associated cells.


Assuntos
Galectinas/metabolismo , Intestinos/parasitologia , Polissacarídeos/metabolismo , Strongyloides ratti/metabolismo , Animais , Clonagem Molecular , Citocinas/metabolismo , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Feminino , Galectinas/genética , Expressão Gênica , Perfilação da Expressão Gênica , Hemaglutinação , Masculino , Ligação Proteica , Ratos Wistar , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Strongyloides ratti/genética
2.
Rev Sci Tech ; 37(3): 985-997, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30964454

RESUMO

A cross-sectional study was conducted in five regions in Saudi Arabia to investigate the epidemiology of Middle East respiratory syndrome coronavirus (MERS-CoV) infection in dromedary camels (Camelus dromedarius) during April and May2015. Serum and nasal swab samples were tested for MERS-CoV antibodies andribonucleic acid (RNA) using a recombinant enzyme-linked immunosorbent assay (rELISA) and real-time reverse-transcription polymerase chain reaction (rRT-PCR), respectively. The overall MERS-CoV antibody seroprevalence was 80.5%, whereas the overall viral RNA prevalence was 2.4%. The associations of risk factors with each prevalence were quantified using univariate and multivariate analyses. The multivariate models identified region, age, grazing system, exposure to wild animals and dung removal as factors significantly associated with seroprevalence (p ??0.05). A higher seroprevalence was more likely to occur in camels from the Riyadh, Eastern, Northern and Makkah regions than those from the Jazan region; camels ??4 and 1-3 years of age (marginally significant) than calves < 1 year; and camels raised in zero grazing and semi-open grazing systems than those raised in an open grazing system. However, the presence of wild animals and daily dung removal were negatively associated with seroprevalence. On the other hand, region and sex were significantly associated with MERS-CoV RNA prevalence(p ??0.05). A higher viral RNA prevalence was more likely to occur in camels from the Riyadh region and Eastern region (marginally significant) than in those from the Makkah region, and in male camels than female camels. In conclusion, the risk factors identified in this study can be considered to be predictors of MERS-CoV infection in camels and should be taken into account when developing an efficient and cost-effective control strategy.


Une étude transversale a été réalisée au cours des mois d'avril et de mai 2015 dans cinq régions d'Arabie saoudite afin d'élucider l'épidémiologie de l'infection par le coronavirus responsable du syndrome respiratoire du Moyen-Orient(MERS­CoV) chez les dromadaires (Camelus dromedarius). Des échantillons de sérum et des écouvillons nasaux prélevés de dromadaires ont été analysés afin de détecter la présence d'anticorps dirigés contre le MERS-CoV ou d'ARN de ce même virus, en utilisant respectivement une épreuve immuno-enzymatique recombinante (ELISAr) et une amplification en chaîne par polymérase couplée à une transcription inverse (PCR­RT) en temps réel. La prévalence sérologique globale des anticorps dirigés contre le MERS-CoV s'élevait à 80,5 %, tandis que la prévalence globale de l'ARN viral était de 2,4 %. Les corrélations entre les facteurs de risque et les prévalences obtenues ont été quantifiées au moyen d'analyses à une seule et à plusieurs variables. Les modèles à plusieurs variables ont fait apparaître une association significative (p ??0,05) entre la prévalence sérologique et les facteurs suivants : la région, l'âge des animaux, le système pastoral pratiqué, l'exposition à la faune sauvage et l'élimination du fumier. La probabilité d'une forte prévalence sérologique était plus élevée chez les dromadaires provenant des régions de Riyad, de l'Est, du Nord et de la Mecque que chez ceux de la région de Jizan ; chez les dromadaires âgés de plus de quatre ans, ou âgés d'un à trois ans (différence marginalement significative) plutôt que chez les jeunes de moins d'un an ; et enfin chez les dromadaires nourris en stabulation (zéro pâturage) ou en pâturage semi-ouvert plutôt que chez ceux nourris dans des systèmes de pâturage ouvert. En revanche, une corrélation négative a été constatée entre la prévalence sérologique d'une part et la présence d'animaux sauvages et/ou l'élimination quotidienne du fumier, d'autre part. En ce qui concerne la détection virale, une corrélation significative (p ??0,05) a été constatée entre la région et le sexe des animaux et la prévalence de l'ARN du MERS-CoV. La probabilité d'une prévalence plus élevée de l'ARN viral était plus prononcée chez les dromadaires des régions de Riyad et de l'Est (différence marginalement significative) que chez ceux de la région de La Mecque, et chez les mâles que chez les chamelles. En conclusion, les facteurs de risque identifiés dans cette étude peuvent servir d'annonciateurs de l'infection par le MERS-CoV chez les dromadaires et devraient être pris en compte pour élaborer une stratégie efficace et rentable de lutte contre cette maladie.


Los autores describen un estudio transversal efectuado en abril y mayo de 2015 en cinco regiones de Arabia Saudí con objeto de investigar la epidemiologia de la infección de dromedarios (Camelus dromedarius) por el coronavirus del síndrome respiratorio de Oriente Medio (MERS­CoV). A tal efecto se analizaron muestras de suero y exudado nasal para detectar en ellas anticuerpos contra el MERS­CoV y ácido ribonucleico (ARN) del virus, empleando para ello, respectivamente, una técnica de ensayo inmunoenzimático recombinante (ELISAr) y una de reacción en cadena de la polimerasa acoplada a transcripción inversa en tiempo real (rRT­PCR, por sus siglas en inglés). Se calculó que la seroprevalencia global de anticuerpos contra el virus era del 80,5% y que la prevalencia global de ARN vírico era del 2,4%. Utilizando análisis multifactoriales y de una sola variable se cuantificó también la correlación de cada una de esas prevalencias con una serie de factores de riesgo. Con los modelos multifactoriales se observó que la región, la edad, el régimen de pastoreo, la exposición a animales salvajes y la retirada de estiércol eran factores que presentaban una asociación significativa con la seroprevalencia (p ??0,05): era más probable encontrar niveles elevados de seroprevalencia en dromedarios de las regiones de Riad y La Meca y las regiones oriental y septentrional del país que en los de la región de Jizán; en los de 4 o más años y entre 1 y 3 años de edad (correlación ligeramente significativa) que en las crías menores de 1 año; y en los animales estabulados o criados en sistemas de pasto semiabierto que en los criados con regímenes de pasto al aire libre. La presencia de animales salvajes y la retirada cotidiana del estiércol, por su parte, presentaban una correlación negativa con la seroprevalencia. Por otro lado, los factores asociados significativamente con la prevalencia de ARN vírico (p ??0,05) eran la región y el sexo: había mayor probabilidad de encontrar niveles elevados de prevalencia de ARN vírico en dromedarios de la región de Riad y la región oriental (correlación ligeramente significativa) que en los de la región de La Meca, y en machos más que en hembras. En conclusión, los factores de riesgo detectados con este estudio pueden ser considerados predictivos de la infección de dromedarios por el MERS­CoV y deben ser tenidos en cuenta para elaborar una estrategia de lucha que ofrezca a la vez eficacia y rentabilidad.


Assuntos
Infecções por Coronavirus , Coronavírus da Síndrome Respiratória do Oriente Médio , Animais , Camelus , Infecções por Coronavirus/veterinária , Estudos Transversais , Feminino , Masculino , Arábia Saudita , Estudos Soroepidemiológicos
3.
Tissue Cell ; 42(3): 165-75, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20434749

RESUMO

In this study the long-term effects of morphine sulphate treatment (MST) on histopathological and biochemical changes in the cerebellum was assessed in albino rats. Normal saline (5ml) was given orally as placebo in the control group (n=25). Morphine groups received morphine orally at a dose level of 5mg/kg body weight day after day for 10, 20 and 30 days (n=25/group). Light microscopy revealed that the molecular layer showed vacuolation. The Purkinje cells lost their specific shaped appearance, decreased in size and numbers. The granular cells highly degenerated. Electron microscopy revealed fragmentation of the cisterns of the both types of endoplasmic reticulum, resulted in a progressive depletion of total protein contents as well as general carbohydrates in all treated groups as supported by histochemical observation. Obvious destruction of mitochondrial inner membrane and cristae mediate cell death. Also, abnormal nucleus with deformed perforated nuclear membrane and deformation of the plasma membrane with degeneration of the synapses could interpreted as a sign of necrosis. Biochemical analysis revealed that dopamine (DA) and norepinephrine (NE) were significantly decreased in four brain areas (cortex striatum, thalamus/hypothalamus, and cerebellum). In contrast, serotonin (5-HT) level was increased in these brain regions; with an exception of 5-HT on day 10 and neurotransmitter levels in the pons were unaffected. The quantitative analysis showed a significant decrease (P<0.05) in the diameter of Purkinje cells and in the thickness of both molecular and granular layers treated groups. Morphine sulphate induces may be a cell death or necrosis in the rat cerebellum and modulating neurotransmitter system. Our findings pointed out the risk of increased cerebellum damage due to long-term of morphine use.


Assuntos
Albinismo , Cerebelo/metabolismo , Cerebelo/patologia , Morfina/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Cerebelo/efeitos dos fármacos , Dopamina/metabolismo , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/patologia , Retículo Endoplasmático/ultraestrutura , Imuno-Histoquímica , Morfina/administração & dosagem , Norepinefrina/metabolismo , Células de Purkinje/metabolismo , Células de Purkinje/patologia , Células de Purkinje/ultraestrutura , Ratos , Serotonina/metabolismo
4.
Zentralbl Bakteriol Naturwiss ; 135(3): 252-9, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-6775436

RESUMO

The effects of 2,4-D on respiration, carbohydrate and nitrogen metabolism have excited much interest in relation to higher plants (Hansen 1946, Hseuth and Lou 1946, SMITH et al. 1947, and Said and Naguib 1955). But the effects of 2,4-D on dungi have been tackled to a much less extent (Guiscafre-Arrilaga 1948, Bever and Slife 1948, Wei and Ling 1948, and Manil and Strazewska 1950). These investigators studied the effects exerted on fungal growth. Said and Naguib (1962) studied the effect of 2,4-D on the carbohydrate metabolism of Fusarium moniliforme. They showed that both sucrose inversion and absorption were retarded in the presence of 2,4-D. In the present investigation, a trial was carried out in order to elucidate the effect of 2,4-D on growth, nitrogen and carbohydrate metabolism of Aspergillus terreus when grown on two different nitrogen sources, namely sodium nitrate and ammonium phosphate.


Assuntos
Ácido 2,4-Diclorofenoxiacético/farmacologia , Aspergillus/efeitos dos fármacos , Metabolismo dos Carboidratos , Dióxido de Carbono/metabolismo , Nitrogênio/metabolismo , Aspergillus/análise , Aspergillus/metabolismo , Microbiologia do Solo , Sacarose/metabolismo
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