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1.
Braz. j. biol ; 79(2): 263-272, Apr.-June 2019. tab, graf
Article Dans Anglais | LILACS | ID: biblio-989458

Résumé

Abstract The distribution of most species occurs in delimited regions with unique characteristics called "centers of endemism". In Eastern Amazon is located the Belém Endemism Center (BEC), one of the most intensely deforested in Brazilian Amazon. Here, we show information about orchid bee assemblages based on historical records from entomological collections. For each species, we calculated occurrence frequency and dominance, and we classified them in 3 statuses: common, intermediate or rare species. Curves of observed and estimated richness were built, based on Jackknife estimator. We found 1,257 specimens from 56 species, constituting records from 1917 to 2009, and one species is a new record for BEC. Higher number of specimens and species was concentrated in a few locations and surveys increased from the 70's. The results suggest a high richness of orchid bees in the BEC, although this scenario is far from what is expected for the entire area. The high occurrence of rare species may be related to their low representativeness in the collections, and the proximity between the areas had favored samplings. Even so, the species list and the conservation status presented here may be useful information in studies comparing past and current orchid bee fauna, and, allied to data on bees' responses to land use changes occurred in BEC over the years, can fit as a basis for defining priority areas for conservation.


Resumo A distribuição da maioria das espécies ocorre em regiões delimitadas com características únicas conhecidas como "centros de endemismo". Na Amazônia Oriental está localizado o Centro de Endemismo Belém (CEB), uma das áreas mais intensivamente desmatadas na Amazônia Brasileira. Aqui, apresentamos informações sobre assembleias de abelhas orquídeas baseadas em registros históricos de coleções entomológicas. Para cada espécie, foram calculadas a frequência de ocorrência e a dominância, classificando-as em 3 estados: espécies comuns, intermediárias ou raras. Foram geradas curvas de riqueza observada e estimada, com base no estimador Jackknife. Encontramos 1.257 espécimes de 56 espécies, constituindo registros de 1917 a 2009, e uma espécie é um novo registro no CEB. Maior número de espécimes e espécies foi concentrado em poucos locais, com intensificação nas coletas a partir dos anos70. Os resultados sugerem alta riqueza de abelhas orquídeas no CEB, embora esse cenário esteja longe do que é esperado para toda a área. A elevada ocorrência de espécies raras pode estar relacionada à baixa representatividade nas coleções e a proximidade entre as áreas favoreceu as amostragens. Mesmo assim, a lista de espécies e o estado de conservação aqui apresentados podem ser informações úteis em estudos interessados em comparar a fauna passada e atual de abelhas das orquídeas e, aliado a dados sobre as respostas das abelhas às mudanças de uso da terra ocorridas no CEB ao longo dos anos, podem servir de base para definição de áreas prioritárias para conservação.


Sujets)
Animaux , Histoire du 20ème siècle , Histoire du 21ème siècle , Abeilles/classification , Abeilles/physiologie , Brésil , Espèce en voie de disparition , Conservation des ressources naturelles
2.
Article Dans Anglais | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467190

Résumé

Abstract The distribution of most species occurs in delimited regions with unique characteristics called centers of endemism. In Eastern Amazon is located the Belém Endemism Center (BEC), one of the most intensely deforested in Brazilian Amazon. Here, we show information about orchid bee assemblages based on historical records from entomological collections. For each species, we calculated occurrence frequency and dominance, and we classified them in 3 statuses: common, intermediate or rare species. Curves of observed and estimated richness were built, based on Jackknife estimator. We found 1,257 specimens from 56 species, constituting records from 1917 to 2009, and one species is a new record for BEC. Higher number of specimens and species was concentrated in a few locations and surveys increased from the 70s. The results suggest a high richness of orchid bees in the BEC, although this scenario is far from what is expected for the entire area. The high occurrence of rare species may be related to their low representativeness in the collections, and the proximity between the areas had favored samplings. Even so, the species list and the conservation status presented here may be useful information in studies comparing past and current orchid bee fauna, and, allied to data on bees responses to land use changes occurred in BEC over the years, can fit as a basis for defining priority areas for conservation.


Resumo A distribuição da maioria das espécies ocorre em regiões delimitadas com características únicas conhecidas como centros de endemismo. Na Amazônia Oriental está localizado o Centro de Endemismo Belém (CEB), uma das áreas mais intensivamente desmatadas na Amazônia Brasileira. Aqui, apresentamos informações sobre assembleias de abelhas orquídeas baseadas em registros históricos de coleções entomológicas. Para cada espécie, foram calculadas a frequência de ocorrência e a dominância, classificando-as em 3 estados: espécies comuns, intermediárias ou raras. Foram geradas curvas de riqueza observada e estimada, com base no estimador Jackknife. Encontramos 1.257 espécimes de 56 espécies, constituindo registros de 1917 a 2009, e uma espécie é um novo registro no CEB. Maior número de espécimes e espécies foi concentrado em poucos locais, com intensificação nas coletas a partir dos anos70. Os resultados sugerem alta riqueza de abelhas orquídeas no CEB, embora esse cenário esteja longe do que é esperado para toda a área. A elevada ocorrência de espécies raras pode estar relacionada à baixa representatividade nas coleções e a proximidade entre as áreas favoreceu as amostragens. Mesmo assim, a lista de espécies e o estado de conservação aqui apresentados podem ser informações úteis em estudos interessados em comparar a fauna passada e atual de abelhas das orquídeas e, aliado a dados sobre as respostas das abelhas às mudanças de uso da terra ocorridas no CEB ao longo dos anos, podem servir de base para definição de áreas prioritárias para conservação.

3.
Braz. j. med. biol. res ; 44(6): 562-572, June 2011. ilus, tab
Article Dans Anglais | LILACS | ID: lil-589981

Résumé

Inhibition of type-5 phosphodiesterase by sildenafil decreases capacitative Ca2+ entry mediated by transient receptor potential proteins (TRPs) in the pulmonary artery. These families of channels, especially the canonical TRP (TRPC) subfamily, may be involved in the development of bronchial hyperresponsiveness, a hallmark of asthma. In the present study, we evaluated i) the effects of sildenafil on tracheal rings of rats subjected to antigen challenge, ii) whether the extent of TRPC gene expression may be modified by antigen challenge, and iii) whether inhibition of type-5 phosphodiesterase (PDE5) may alter TRPC gene expression after antigen challenge. Sildenafil (0.1 µM to 0.6 mM) fully relaxed carbachol-induced contractions in isolated tracheal rings prepared from naive male Wistar rats (250-300 g) by activating the NO-cGMP-K+ channel pathway. Rats sensitized to antigen by intraperitoneal injections of ovalbumin were subjected to antigen challenge by ovalbumin inhalation, and their tracheal rings were used to study the effects of sildenafil, which more effectively inhibited contractions induced by either carbachol (10 µM) or extracellular Ca2+ restoration after thapsigargin (1 µM) treatment. Antigen challenge increased the expression of the TRPC1 and TRPC4 genes but not the expression of the TRPC5 and TRPC6 genes. Applied before the antigen challenge, sildenafil increased the gene expression, which was evaluated by RT-PCR, of TRPC1 and TRPC6, decreased TRPC5 expression, and was inert against TRPC4. Thus, we conclude that PDE5 inhibition is involved in the development of an airway hyperresponsive phenotype in rats after antigen challenge by altering TRPC gene expression.


Sujets)
Animaux , Mâle , Rats , Canaux calciques/effets des médicaments et des substances chimiques , Carbachol/pharmacologie , Pipérazines/pharmacologie , Sulfones/pharmacologie , Canaux cationiques TRPC/effets des médicaments et des substances chimiques , Trachée/effets des médicaments et des substances chimiques , Vasodilatateurs/pharmacologie , Canaux calciques/métabolisme , Carbachol/antagonistes et inhibiteurs , Expression des gènes , Lactones/pharmacologie , Contraction musculaire/effets des médicaments et des substances chimiques , Contraction musculaire/physiologie , Monoxyde d'azote/métabolisme , Ovalbumine/pharmacologie , Purines/pharmacologie , Rat Wistar , Sesquiterpènes/pharmacologie , Canaux cationiques TRPC/génétique , Canaux cationiques TRPC/métabolisme , Trachée/métabolisme , Trachée/physiopathologie
4.
Arq. bras. med. vet. zootec ; 63(3): 729-735, June 2011. ilus, tab
Article Dans Portugais | LILACS | ID: lil-595591

Résumé

Avaliou-se o efeito da adição de caroço de algodão à dieta de bovinos confinados sobre o desempenho animal e características da carcaça. Usaram-se 36 novilhos Nelore com médias de idade e peso vivo inicial de 20 meses e 333,5kg. Os animais foram confinados e receberam dietas com os seguintes teores de caroço de algodão: 0; 14,35 por cento; 27,51 por cento; e 34,09 por cento na matéria seca da dieta. O ganho de peso diário, peso vivo final e consumo de matéria seca diminuíram linearmente com o aumento da proporção de caroço de algodão na dieta. Não foi observado efeito sobre o ganho de peso total ajustado ao consumo. Os pesos da carcaça e do contrafilé diminuíram linearmente com o aumento da proporção de caroço de algodão na dieta. Não foi observado efeito do teor de caroço de algodão sobre a área de olho de lombo. A espessura de gordura de cobertura do dorso e da garupa diminuíram com o aumento do teor de caroço de algodão. Observou-se correlação de 0,62 entre as duas medidas de gordura. A adição de caroço de algodão à dieta de bovinos de corte não se mostrou vantajosa, pois diminuiu o desempenho animal e a deposição de gordura na carcaça.


The purpose of this experiment was to evaluate the effect of adding whole cottonseed to the diet of feedlot cattle over the performance and carcass traits. Thirty six Nellore bullocks were used, with an average age of 20 months and average initial weight of 333.5kg. The animals were raised on feedlot and fed diets with the following content of whole cottonseed: 0; 14.35 percent; 27.51 percent; or 34.09 percent on a dry matter basis. The daily weight gain, final weight and dry matter intake decreased linearly as the proportion of cottonseed increased. No effect of cottonseed on total weight gain adjusted for intake was observed. Carcass and ribeye weights decreased linearly as cottonseed content increased. No effect of cottonseed content was observed for ribeye area. In contrast, back fat and rump fat thickness decreased as cottonseed content increased. A correlation of .62 was observed between back fat and rump fat. Adding whole cottonseed to beef cattle diets did not prove advantageous because it reduced animal performance and carcass fat deposition.


Sujets)
Animaux , Bovins , Régime alimentaire/médecine vétérinaire , Aliment pour animaux/analyse , Aliment pour animaux/effets indésirables , Consommation alimentaire , Prise de poids
5.
J. venom. anim. toxins incl. trop. dis ; 17(2): 199-208, 2011. ilus, graf, tab
Article Dans Anglais | LILACS | ID: lil-587780

Résumé

In the present study, the effects of Polybia paulista venom (PPV) on renal and vascular tissues were investigated. Isolated kidneys perfused with PPV (1 and 3 ìg/mL) had increased perfusion pressure, renal vascular resistance, urinary flow, and glomerular filtration rate; and reduced sodium tubular transport. Histological evaluation demonstrated deposits of proteins in Bowman's space and tubular lumen, and focal areas of necrosis. The venom promoted a cytotoxic effect on Madin-Darby canine kidney (MDCK) cells. A significant increase in lactic dehydrogenase levels was observed in response to venom exposure. In isolated mesenteric vascular beds, pressure and vascular resistance augmented in a dose-dependent manner. PPV increased the contractility of aortic rings maintained under basal tension. This contractile response was inhibited when preparations were maintained in Ca2+-free medium. Likewise, verapamil, a voltage-gated calcium channel blocker, also inhibited the contractile response. In this study, phentolamine, a blocker of á-adrenergic receptor blocker, significantly reduced the contractile effect of PPV in the aortic ring. In conclusion, PPV produced nephrotoxicity, which suggests a direct effect on necrotic cellular death in renal tubule cells. The vascular contractile effect of PPV appears to involve calcium influx through voltage-gated calcium channels via adrenergic regulation.


Sujets)
Animaux , Rats , Aorte , Inhibiteurs des canaux calciques , Rein , Venins de guêpe , Phentolamine , Rat Wistar , Vérapamil
6.
J. venom. anim. toxins incl. trop. dis ; 17(3): 333-347, 2011. graf, tab
Article Dans Anglais | LILACS | ID: lil-597233

Résumé

In this study, we evaluated the actions of Crotalus durissus cumanensis venom (CDCmV), and its crotoxin (Crtx) fraction, on renal and vascular functions in Wistar rats. In isolated perfused kidneys, CDCmV (10 µg/mL) significantly increased the perfusion pressure (PP) from 110.7 ± 2.4 to 125.3 ± 2.8 mmHg after 30 minutes. This effect was accompanied by an increased renal vascular resistance (RVR) from 5.4 ± 0.1 to 6.2 ± 0.2 mmHg/mL.g-1.min-1. We observed decreases in urinary flow (UF) from 0.13 ± 0.01 to 0.05 ± 001 mL.g-1.min-1 and glomerular filtration rate (GFR) from 0.66 ± 0.06 to 0.18 ± 0.02 mL.g-1.min-1. Crtx did not change PP or RVR, but diminished GFR (from 0.65 ± 0.05 to 0.26 ± 003 mL.g-1.min-1) and UF (from 0.11 ± 0.008 to 0.09 ± 0.008 mL.g-1.min-1). Both CDCmV and Crtx reduced the percentage of tubular transport of sodium, chloride and potassium. The cytotoxicity of these substances against MDCK cells was tested by the MTT method: only CDCmV caused a decrease in the cell viability with an IC50 of 5.4 µg/mL. In endothelium-intact isolated aortic rings, CDCmV (0.1 to 30 µg/mL) increased the sustained phenylephrine-induced contraction to a value of 130.0 ± 6.6 percent of its corresponding control, but showed a relaxant effect in endothelium-denuded preparations. Similar results were observed in aortic rings contracted with potassium (40 mM). Crtx was ineffective in aortic ring assays. Thus, it is reasonable to suggest that the renal effects induced by the CDCmV may be due to its influence on the endothelium's ability to release factors that can alter the contractile behavior of vascular smooth muscle. In conclusion, CDCmV is toxic to kidney cells. It changes parameters of the renal function including the glomerular filtration rate, renal vascular resistance and tubular transport. The actions induced by CDCmV also involve endothelium-dependent vasoactive properties. Their effects may be only partially attributed to Crtx.


Sujets)
Animaux , Femelle , Rats , Crotalus , Crotoxine , Rat Wistar , Venins de crotalidé/toxicité
7.
Arq. Inst. Biol. (Online) ; 77(4): 741-750, out.-dez. 2010.
Article Dans Portugais | VETINDEX, LILACS | ID: biblio-1395925

Résumé

Os métodos moleculares de detecção rápida e eficaz de lotes de aves infectados por bactérias como Salmonella sp. Campylobacter sp. e Listeria monocytogenes são importantes para reduzir a frequência da transmissão destes patógenos entre os lotes de aves e aos consumidores de produtos de origem animal. Recentemente, as técnicas de biologia molecular, em especial a reação em cadeia polimerase, que permite a amplificação específica de segmentos de DNA, têm possibilitado novos rumos na identificação de bactérias supracitadas, reduzindo o tempo de cultivo e ampliando a confiabilidade das provas diagnósticas. A utilização da biologia molecular por laboratórios de diagnóstico humano e animal, assim como em programas de controle de qualidade de alimentos e produtos de origem animal, já é realidade e tende a se expandir rapidamente. O objetivo deste artigo é fazer uma breve revisão dos testes diagnósticos convencionais e moleculares para identificar Campylobacter sp., Salmonella sp. e Listeria monocytogenes. Concluindo, o diagnóstico molecular é um campo em avanço científico e tecnológico, no qual novas técnicas moleculares estão em desenvolvimento para o diagnóstico de bactérias em alimentos.


The molecular methods for quick and efficient detection of chicken lots infected by bacteria such as Salmonella sp. Campylobacter sp. and Listeria monoytogenes is basic for the effort to reduce the frequency of the transmission between chicken lots and to the consumers of poultry products. Recently, the development of techniques involving molecular biology, especially polymerase chain reaction, which allows the specific enlargement of segments of DNA, has been making new procedures possible for the identification of the abovementioned bacteria, reducing the time necessary for the tests and enhancing the reliability of the resulting diagnoses. The use of molecular biology in laboratories for human and animal diagnosis, as well as in quality control programs for foods and products of animal origin is already a reality and has tended to expand quickly. The objective of this article is to present a brief review of the conventional diagnostic and molecular tests for the identification of Campylobacter sp., Salmonella sp. and Listeria monocytogenes. In conclusion, molecular diagnosis is a field undergoing scientific and technological advancement, in which new molecular techniques are under development for the diagnosis of bacteria in foods.


Sujets)
Animaux , Volaille/microbiologie , Salmonelloses animales/diagnostic , Infections à Campylobacter/diagnostic , Infections à Listeria/diagnostic , Salmonella/isolement et purification , Campylobacter/isolement et purification , Techniques microbiologiques/méthodes , Listeria monocytogenes/isolement et purification
8.
Acta cir. bras ; 20(supl.1): 242-246, 2005.
Article Dans Portugais | LILACS | ID: lil-474160

Résumé

PURPOSE: The objective was to evaluate the quality of diet and the relationship between protein diet and calciuria in children and adolescents with nephrolithiasis. METHODS: Forty-nine children and adolescents (28 male and 21 female; 10.1 +/- 3.16 years old) with nephrolithiasis were included in study. Diet evaluation was performed over a 3 day period in order to determine nutrient consumption. The analysis of diets were carried out by DietWin Clínico 3.0 software. One 24-hour urine sample was collected for the measurement of calcium. Nutritional status was also assessed by Body Mass Index (BMI). RESULTS: The diet of patients containe insufficient energy and calcium. High levels of protein (69.64 +/- 16.42 gm), mainly animal source (65.81 +/- 11.45%) and low levels of calcium (500.95 +/- 284.64 mg) was observed (95%). Analysis of 24 hour urine samples revealed that 25.0% of the patients presented hypercalciuria. A positive correlation (r = 0.26680) between animal protein intake and calciuria was found, in opposite of vegetable protein and calciuria correlation (r = -0.2675). CONCLUSIONS: Animal protein of the diet has a significant effect in urinary excretion of calcium in patients with nephrolithiasis.


Sujets)
Adolescent , Enfant , Enfant d'âge préscolaire , Femelle , Humains , Mâle , Calcium/urine , Régime alimentaire , État nutritionnel/physiologie , Phénomènes physiologiques nutritionnels chez l'enfant/physiologie , Néphrolithiase/métabolisme , Protéines alimentaires/administration et posologie , Indice de masse corporelle , Enquêtes sur le régime alimentaire , Phénomènes physiologiques nutritionnels chez l'adolescent/physiologie , Comportement alimentaire/physiologie , Ration calorique/physiologie , Néphrolithiase/urine , Protéines alimentaires/métabolisme
10.
Rev. Inst. Med. Trop. Säo Paulo ; 32(5): 328-37, set.-out. 1990. ilus, tab
Article Dans Anglais | LILACS | ID: lil-103604

Résumé

Numa tentativa de estar o mais próximo possível a pacientes infectados e tratados nas áreas endêmicas de esquistosomose (S. mansoni) e também para obter um período mais longo de seguimento, camundongos foram repetidamente infectado com um número baixo de cercarias. Dados de sobrevivência e variáveis histológicas tais como granuloma esquistosomótico, alteraçöes portais, necrose hepatocelular, regeneraçäo hepática, pigmento esquistosomótico, fibrose periductal e principalmente, alteraçöes dos ductos biliares foram analisados nos animais infectados tratados e näo tratados. Aa terapêutica por oxamniquina ns animais repetidamente infectados prolonga a sobrevivência de maneira singificante (Chi-quadrado 9,24, p = 0,0024), portanto confirmando resultados anteriores com um modelo semelhante mas com um período mais curto de seguimento. Ainda, a mortalidadade decresce rapidamente depois do tratamento, sugerindo uma abrupta reduçäo na gravidade das lesöes hepáticas. O fígado foi anida estudados sob o ponto de vista morfológico imunohistoquímico. Fibrose portal, com um quadro que lembra a fibrose humana do tipo Symmers está presente na fase tardia da infecçäo. As alteraçöes de ductos biliares säo muito próximas daquelas descritas na esquistosomose manônica humana. Antígeno esquistomótico foi observado e, uma célula isolada do revestimento alterado de ductos biliares. A patogênese das alteraçöes ductais e sua possível relaçäo com a infecçäo parasitária e/ou seus antígenos foi discutida


Sujets)
Souris , Animaux , Femelle , Conduits biliaires/anatomopathologie , Parasitoses hépatiques/anatomopathologie , Schistosomiase à Schistosoma mansoni/anatomopathologie , Antigènes d'helminthe/isolement et purification , Conduits biliaires/parasitologie , Parasitoses hépatiques/traitement médicamenteux , Foie/anatomopathologie , Oxamniquine/usage thérapeutique , Schistosoma mansoni/immunologie , Schistosomiase à Schistosoma mansoni/traitement médicamenteux
12.
Rev. Inst. Med. Trop. Säo Paulo ; 24(6): 349-52, 1982.
Article Dans Anglais | LILACS | ID: lil-10922

Résumé

Camundongos SW, machos, infectados com a cepa FL ou com a Y do T.cruzi foram decomplementados com CVF. A parasitemia dos camundongos decomplementados e infectados com a cepa FL foi significativamente mais alta no 10o dia de infeccao do que a do grupo controle, infectado mas normocomplementemico, mas nao no 12o dia. A parasitemia dos camundongos decomplementados e infectados com a cepa Y nao foi significativamente diferente da dos controles nem no 5o, nem no 7o dia de infeccao. O exame histopatologico do coracao demonstrou que a intensidade da resposta inflamatoria dos camundongos infectados com a cepa Y e pouco menor para os controles. Nao foram observadas diferencas significativas no grau da resposta inflamatoria entre os camundongos decomplementados e os nao decomplementados, infectados com a cepa FL do T.cruzi


Sujets)
Mâle , Animaux , Souris , Maladie de Chagas , Protéines du système du complément , Cardiomyopathie associée à la maladie de Chagas
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