RESUMEN
Primary brain tumors remain among the deadliest of all cancers. Glioma grade IV (glioblastoma), the most common and malignant type of brain cancer, is associated with a 5-year survival rate of < 5%. Melatonin has been widely reported as an anticancer molecule, and we have recently demonstrated that the ability of gliomas to synthesize and accumulate this indolamine in the surrounding microenvironment negatively correlates with tumor malignancy. However, our understanding of the specific effects mediated through the activation of melatonin membrane receptors remains limited. Thus, here we investigated the specific roles of MT1 and MT2 in gliomas and medulloblastomas. Using the MT2 antagonist DH97, we showed that MT1 activation has a negative impact on the proliferation of human glioma and medulloblastoma cell lines, while MT2 activation has an opposite effect. Accordingly, gliomas have a decreased mRNA expression of MT1 (also known as MTNR1A) and an increased mRNA expression of MT2 (also known as MTNR1B) compared to the normal brain cortex. The MT1/MT2 expression ratio negatively correlates with the expression of cell cycle-related genes and is a positive prognostic factor in gliomas. Notably, we showed that functional selective drugs that simultaneously activate MT1 and inhibit MT2 exert robust anti-tumor effects in vitro and in vivo, downregulating the expression of cell cycle and energy metabolism genes in glioma stem-like cells. Overall, we provided the first evidence regarding the differential roles of MT1 and MT2 in brain tumor progression, highlighting their relevance as druggable targets. KEY MESSAGES: ⢠MT1 impairs while MT2 promotes the proliferation of glioma and medulloblastoma cell lines. ⢠Gliomas have a decreased expression of MT1 and an increased expression of MT2 compared to normal brain cortex. ⢠Tumors with a high MT1/MT2 expression ratio have significantly better survival rates. ⢠Functional selective drugs that simultaneously activate MT1 and inhibit MT2 downregulate the expression of cell cycle and energy metabolism genes in glioma stem-like cells and exert robust anti-tumor effects in vivo.
Asunto(s)
Neoplasias Encefálicas , Glioma , Receptor de Melatonina MT1 , Receptor de Melatonina MT2 , Animales , Encéfalo/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Proliferación Celular , Progresión de la Enfermedad , Femenino , Glioma/genética , Glioma/metabolismo , Glioma/mortalidad , Glioma/patología , Humanos , Estimación de Kaplan-Meier , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Receptor de Melatonina MT1/genética , Receptor de Melatonina MT1/metabolismo , Receptor de Melatonina MT2/genética , Receptor de Melatonina MT2/metabolismoRESUMEN
It is known that the level of dietary protein modulates the enzymatic activity of the digestive tract of fish; however, its effect at the molecular level on these enzymes and the hormones regulating appetite has not been well characterised. The objective of this study was to evaluate the effect of CP on the activity of proteases and the expression of genes related to the ingestion and protein digestion of juveniles of red tilapia (Oreochromis sp.), as well as the effects on performance, protein retention and body composition of tilapia. A total of 240 juveniles (29.32 ± 5.19 g) were used, distributed across 20 tanks of 100 l in a closed recirculation system. The fish were fed to apparent satiety for 42 days using four isoenergetic diets with different CP levels (24%, 30%, 36% and 42%). The results indicate that fish fed the 30% CP diet exhibited a higher growth performance compared to those on the 42% CP diet (P < 0.05). Feed intake in fish fed 24% and 30% CP diets was significantly higher than that in fish fed 36% and 42% CP diets (P < 0.05). A significant elevation of protein retention was observed in fish fed with 24% and 30% CP diets. Fish fed with 24% CP exhibited a significant increase in lipid deposition in the whole body. The diet with 42% CP was associated with the highest expression of pepsinogen and the lowest activity of acid protease (P < 0.05). The expression of hepatopancreatic trypsinogen increased as CP levels in the diet increased (P < 0.05) up to 36%, whereas trypsin activity showed a significant reduction with 42% CP (P < 0.05). The diet with 42% CP was associated with the lowest intestinal chymotrypsinogen expression and the lowest chymotrypsin activity (P < 0.05). α-amylase expression decreased with increasing (P < 0.05) CP levels up to 36%. No significant differences were observed in the expression of procarboxypeptidase, lipase or leptin among all the groups (P > 0.05). In addition, the diet with 42% CP resulted in a decrease (P < 0.05) in the expression of ghrelin and insulin and an increase (P < 0.05) in the expression of cholecystokinin and peptide yy. It is concluded that variation in dietary protein promoted changes in the metabolism of the red tilapia, which was reflected in proteolytic activity and expression of digestion and appetite-regulating genes.
Asunto(s)
Cíclidos , Proteínas en la Dieta , Tilapia , Alimentación Animal/análisis , Animales , Cíclidos/genética , Dieta/veterinaria , Expresión Génica , Tilapia/metabolismoRESUMEN
Protein is the most costly nutrient in fish feed, and while diets offered in the early stages of development typically have high levels of CP, they do not always correspond to the real requirements of the animals. Thus, research that seeks to learn the true nutritional requirements of fish is fundamental to improving commercial fish culture. The present study evaluated the protein requirements of Nile tilapia (Oreochromis niloticus) under larviculture. Fish performance, gene expression for digestive enzymes and their enzymatic activity and stress response to air exposure were analyzed. Four experimental diets differing in CP level were formulated: 30%, 36%, 42% and 48%. Fish larvae were fed the experimental diets during development and sampled 10, 20 and 30 days after the beginning of the experiment for performance, gene expression and enzymatic activity. At sampling time 30, stress resistance was also evaluated by means of an air exposure test. At sampling time 10, CP levels between 36% and 48% could be used for a better performance. During this period, pepsinogen expression was greater for 30% CP, intermediate for 42% and lower for 36% and 48%. After this initial period, diets of between 30% and 42% CP are recommended for better performance. At sampling time 20, gene expression for digestive enzymes and their enzymatic activity were similar for all diets tested. At sampling time 30, the diet of 42% CP induced both greater pepsinogen expression and pepsin activity. Survival after the air exposure test after 30 days of feeding was influenced by CP level in the diet, with the highest survival being for fish fed with 36% CP. Taken together, the present results demonstrate that dietary CP influences digestive enzyme gene expression and activity, and suggest that the best CP levels for Nile tilapia larviculture vary depending on larval stage.
Asunto(s)
Alimentación Animal/análisis , Cíclidos/crecimiento & desarrollo , Dieta/veterinaria , Proteínas en la Dieta/administración & dosificación , Alimentación Animal/normas , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Cíclidos/genética , Cíclidos/metabolismo , Dieta/normas , Regulación Enzimológica de la Expresión Génica , Larva/enzimología , Larva/genética , Larva/crecimiento & desarrolloRESUMEN
The objective of this study was to investigate the influence of two cleaning and disinfection programs on broiler performance and on the microbiological status of the facilities. This trial was an observational study of comparative character. Two experiments were conducted, with 960 birds each. Both experiments were carried out in a positive-pressure broiler house. Broilers were distributed in pens equipped with a bell drinker and a tube feeder each. In the first experiment, new wood shavings were used as litter material, and in the second, reused wood shavings were used. Two treatments with16 replicates of 30 birds each were evaluated. The regular treatment consisted of dry and wet organic matter removal, followed by washing. The European treatment consisted of dry organic matter removal, humidification, washing with water under high pressure, detergent application, rinsing, and application of two combined disinfectants: glutaraldehyde 250g/L + formaldehyde 185g/L; p-chlor-m-cresol 210 g/L. Biosecurity measures were adopted during daily management tasks to prevent cross contamination between treatments. The effectiveness of the treatments was evaluated by microbiological analysis performed before and after treatment applications, as well as by broiler performance results. Live performance results were similar between both treatments when broilers were reared on new litter. When reused word-shavings were used as litter material, the European treatment promoted better broiler performance. The European treatment was more effective than the regular treatment in reducing total microbial counts in the facilities when reused wood shavings were used as litter material, and positively influenced broiler performance.
Asunto(s)
Animales , Pollos/microbiología , Desinfectantes/análisis , Desinfectantes/efectos adversosRESUMEN
The objective of this study was to investigate the influence of two cleaning and disinfection programs on broiler performance and on the microbiological status of the facilities. This trial was an observational study of comparative character. Two experiments were conducted, with 960 birds each. Both experiments were carried out in a positive-pressure broiler house. Broilers were distributed in pens equipped with a bell drinker and a tube feeder each. In the first experiment, new wood shavings were used as litter material, and in the second, reused wood shavings were used. Two treatments with16 replicates of 30 birds each were evaluated. The regular treatment consisted of dry and wet organic matter removal, followed by washing. The European treatment consisted of dry organic matter removal, humidification, washing with water under high pressure, detergent application, rinsing, and application of two combined disinfectants: glutaraldehyde 250g/L + formaldehyde 185g/L; p-chlor-m-cresol 210 g/L. Biosecurity measures were adopted during daily management tasks to prevent cross contamination between treatments. The effectiveness of the treatments was evaluated by microbiological analysis performed before and after treatment applications, as well as by broiler performance results. Live performance results were similar between both treatments when broilers were reared on new litter. When reused word-shavings were used as litter material, the European treatment promoted better broiler performance. The European treatment was more effective than the regular treatment in reducing total microbial counts in the facilities when reused wood shavings were used as litter material, and positively influenced broiler performance.(AU)
Asunto(s)
Animales , Pollos/microbiología , /efectos adversos , /análisis , Desinfectantes/efectos adversos , Desinfectantes/análisisRESUMEN
An experiment was carried out with 1200 23-week-old white Dekalb commercial laying hens to investigate production responses, egg quality, and energy utilization of laying hens fed different dietary energy levels at the beginning of lay. Birds were housed and divided in five groups of 240 birds according to dietary apparent metabolizable energy corrected for nitrogen (AMEn): 2700 kcal/kg; 2775 kcal/kg; 2850 kcal/kg; 2925 kcal/kg; and 3000 kcal/kg, with six replicates of 40 birds each. Birds were fed the experimental diets based on corn and soybean meal for 17 weeks. Diets were iso-nutritive, except for energy level. Increasing AMEn levels had a negative effect on egg production and egg mass (p0.05). AMEn levels did not influence body weight, egg weight, or livability (p>0.05). Increasing AMEn levels increased (p0.05) feed intake and AMEn conversion ratio and feed conversion ratio. AMEn intake remained constant, independently of dietary AMEn level (p>0.05). There were no differences in albumen height, yolk total solids content, or egg component percentages (p>0.05). Egg specific weight improved with increasing AMEn levels (p0.05). Therefore, the energy level of 2700 kcal/kg of feed may be fed to young laying hens.
Asunto(s)
Animales , Aves de Corral/crecimiento & desarrollo , Aves de Corral/embriología , Fuentes Generadoras de Energía/análisis , Huevos/análisis , DietaRESUMEN
An experiment was carried out with 1200 23-week-old white Dekalb commercial laying hens to investigate production responses, egg quality, and energy utilization of laying hens fed different dietary energy levels at the beginning of lay. Birds were housed and divided in five groups of 240 birds according to dietary apparent metabolizable energy corrected for nitrogen (AMEn): 2700 kcal/kg; 2775 kcal/kg; 2850 kcal/kg; 2925 kcal/kg; and 3000 kcal/kg, with six replicates of 40 birds each. Birds were fed the experimental diets based on corn and soybean meal for 17 weeks. Diets were iso-nutritive, except for energy level. Increasing AMEn levels had a negative effect on egg production and egg mass (p0.05). AMEn levels did not influence body weight, egg weight, or livability (p>0.05). Increasing AMEn levels increased (p0.05) feed intake and AMEn conversion ratio and feed conversion ratio. AMEn intake remained constant, independently of dietary AMEn level (p>0.05). There were no differences in albumen height, yolk total solids content, or egg component percentages (p>0.05). Egg specific weight improved with increasing AMEn levels (p0.05). Therefore, the energy level of 2700 kcal/kg of feed may be fed to young laying hens.(AU)
Asunto(s)
Animales , Aves de Corral/embriología , Aves de Corral/crecimiento & desarrollo , Huevos/análisis , Fuentes Generadoras de Energía/análisis , DietaRESUMEN
This study aimed to evaluate diets supplemented with prebiotic, probiotic and symbiotic as an alternative to antibiotics on the performance and immune response against the virus of Newcastle disease in broiler chickens. 1,400 one-day old male Cobb 500 chicks were raised until 42 days old in a completely randomized design with 2x2+1 factorial scheme with seven replications. The treatments were: diet without supplementation (base diet - BD), BD + prebiotic, BD + probiotic, BD + symbiotic (prebiotic + probiotic), and BD + antibiotic. The parameters evaluated were performance and antibody serum titers against Newcastle disease. No antibiotic effect was observed on performance. The symbiotic provided better results for weight gain and feed:gain ratio until 21 days old than isolated additives. At 28 days old, the broilers fed diets with prebiotic presented better feed: gain ratio. In the same period (28 d-old), there was an antibody production increase against the Newcastle disease virus in the group supplemented with prebiotic. It can be concluded that the utilization of symbiotic in broiler chickens' diets can substitute performance enhancing antibiotics. The inclusion of prebiotic in the diet improves feed: gain ratio at 1-28 days old. The chickens' immune response increases at 28 days against the Newcastle disease virus in the group supplemented with prebiotic.(AU)
Asunto(s)
Animales , Aves de Corral/crecimiento & desarrollo , Aves de Corral/microbiología , Prebióticos/administración & dosificación , Prebióticos/análisis , Probióticos/administración & dosificación , Probióticos/análisis , Simbióticos/administración & dosificación , Simbióticos/análisis , Antibacterianos/análisis , Inmunidad Mucosa , Vacunas/análisisRESUMEN
The aim of this work was to evaluate different transport times for pacama juvenile (Lophiosilurus alexandri) previously trained to feed formulated diets. Four hundred and eighty-six pacama juveniles (2.52±0.71g) were submitted to 24 hours of fasting before transport. The animals were divided into nine plastic bags, with density of 54 juveniles in 5L of clean water for each bag after that inflated with pure oxygen and then sealed. Fish were transported for three hours and bags were open at 5, 6 and 7.5 hours after closing. For each time three replications were used. Survival was monitored for 96 hours post-transport. The longest time tested showed the lowest values of dissolved oxygen and pH, while the total ammonia was similar in the different treatments. Survival was 100% for different transport times after 96 hours. Some juveniles returned to feed 48 hours and the majority 72 hours after opening the bags, suggesting the efficiency of transport made at different times.(AU)
Asunto(s)
Animales , Carnívoros , PecesRESUMEN
The aim of this work was to evaluate different transport times for pacama juvenile (Lophiosilurus alexandri) previously trained to feed formulated diets. Four hundred and eighty-six pacama juveniles (2.52±0.71g) were submitted to 24 hours of fasting before transport. The animals were divided into nine plastic bags, with density of 54 juveniles in 5L of clean water for each bag after that inflated with pure oxygen and then sealed. Fish were transported for three hours and bags were open at 5, 6 and 7.5 hours after closing. For each time three replications were used. Survival was monitored for 96 hours post-transport. The longest time tested showed the lowest values of dissolved oxygen and pH, while the total ammonia was similar in the different treatments. Survival was 100% for different transport times after 96 hours. Some juveniles returned to feed 48 hours and the majority 72 hours after opening the bags, suggesting the efficiency of transport made at different times.
Asunto(s)
Animales , Carnívoros , PecesRESUMEN
Foram utilizadas 1200 poedeiras comerciais da linhagem Lohmann LSL, com 64 semanas, em gaiolas convencionais. Estas foram divididas em cinco grupos, de acordo com o nível de energia metabolizável aparente corrigida pelo nitrogênio (EMAn) presente em sua dieta: 2700kcal/kg; 2775kcal/kg; 2850kcal/kg; 2925kcal/kg; e 3000kcal/kg, com seis repetições. As aves receberam as rações, á base de milho e farelo de soja, por 16 semanas. O delineamento experimental foi inteiramente ao acaso, e as médias foram submetidas à regressão polinomial e ao teste de Kruskal-Wallis. O aumento de EMAn não exerceu efeito sobre a produção, a massa e o peso de ovos, bem como sobre o peso das aves e a viabilidade. O consumo de ração diminuiu de acordo com o aumento na energia da dieta, porém a conversão energética foi pior com esse aumento. Em contrapartida, a conversão alimentar melhorou o aumento dos níveis de EMAn. O consumo de EMAn é constante independentemente do seu nível dietético. Não há diferença nas unidades Haugh, nos sólidos da gema e na porcentagem dos componentes do ovo. O peso específico melhora com o aumento dos níveis de EMAn. Os níveis nutricionais para poedeiras velhas podem estar sendo superestimados.(AU)
A total of 1200 Lohmann LSL laying hens, with 64 weeks of age in conventional cages was used. These were divided into five groups according to the level of apparent metabolizable energy corrected for nitrogen retention (AMEn) present in the diet: 2700kcal/kg; 2775kcal/kg; 2850kcal/kg; 2925kcal/kg and 3000kcal/kg, with six replicates. The birds received the diets based on corn and soybean meal for 16 weeks. The experimental design was completely randomized and the means were submitted to polynomial regression and the Kruskal-Wallis test. The increased level of AMEn had no effect on production, egg mass and weight. There was no influence of AMEn on bird weight, egg weight and viability. Feed intake decreased with increasing levels, however, and the conversion of AMEn was worse with its increase, and in return feed conversion worsened with increasing consumption. AMEn is constant regardless of the level of the feed. There is no difference in Haugh units, yolk solids and percentage of egg components. The specific gravity improves with increasing levels of AMEn. The nutritional levels for older laying hens may be overestimated.(AU)
Asunto(s)
Animales , Proteínas del Huevo/análisis , Pollos/crecimiento & desarrollo , Pollos/metabolismo , Pollos/fisiologíaRESUMEN
Most studies in nutrition for the South American catfish (surubim) were limited to the initial phase of development. However, it is clear that performance and nutrient utilization can change during the life stages of a fish. Therefore, this study aimed to evaluate the performance and nutrient utilization in juveniles of surubim fed diets varying in protein and energy levels. Two experiments were performed to test different levels of energy and protein in formulated diets. In the first experiment, surubim juveniles (89.2±4.8g) were fed five diets containing different levels of energy (18.0, 18.8, 19.6, 20.5, 21.3 MJ/kg). In the second experiment, juveniles (170.03±3.35g) were fed five diets containing different levels of protein (360, 400, 440, 480 and 520g/kg). The most favorable energy level for weight gain was 20.3 MJ/kg. The increasing energy levels provided a rise in fat and decrease in protein whole-body composition. The protein amount was between 360 to 400g/kg (383g/kg), which was adequate for performance and nutrient assimilation in surubim juveniles.(AU)
A maior parte dos estudos a respeito dos aspectos nutricionais do surubim está limitada às primeiras fases de desenvolvimento. Entretanto, é claro que o desempenho e a utilização dos nutrientes podem mudar durante os diferentes estágios de desenvolvimento destes animais. Assim sendo, este estudo teve como objetivo avaliar o desempenho e a utilização de nutrientes em juvenis de surubim alimentados com dietas contendo níveis variáveis de energia e proteína. Dois experimentos foram realizados para testar os diferentes níveis de proteína e energia. No primeiro experimento, juvenis de surubim (89,2±4,8g) foram alimentados com cinco dietas contendo níveis diferentes de energia (18.0, 18.8, 19.6, 20.5, 21.3MJ/kg). No segundo experimento, os juvenis (170,03±3,35g) foram alimentados com dietas contendo cinco níveis de proteína (360, 400, 440, 480 e 520g/kg). O melhor nível de energia para ganho de peso foi 20,3 MJ/kg. O aumento dos níveis de energia levou a um incremento nos níveis de lipídeo e diminuição da proteína corporal. Níveis de proteína entre 360 a 400g/kg foram os mais adequados para o desempenho e utilização dos nutrientes em juvenis grandes de surubim.(AU)
Asunto(s)
Animales , Análisis de Secuencia de Proteína/veterinaria , Fenómenos Fisiológicos Nutricionales de los Animales/fisiología , Peces/anatomía & histología , Peces/clasificación , Peces/genéticaRESUMEN
Foram utilizadas 1200 poedeiras comerciais da linhagem Lohmann LSL, com 64 semanas, em gaiolas convencionais. Estas foram divididas em cinco grupos, de acordo com o nível de energia metabolizável aparente corrigida pelo nitrogênio (EMAn) presente em sua dieta: 2700kcal/kg; 2775kcal/kg; 2850kcal/kg; 2925kcal/kg; e 3000kcal/kg, com seis repetições. As aves receberam as rações, á base de milho e farelo de soja, por 16 semanas. O delineamento experimental foi inteiramente ao acaso, e as médias foram submetidas à regressão polinomial e ao teste de Kruskal-Wallis. O aumento de EMAn não exerceu efeito sobre a produção, a massa e o peso de ovos, bem como sobre o peso das aves e a viabilidade. O consumo de ração diminuiu de acordo com o aumento na energia da dieta, porém a conversão energética foi pior com esse aumento. Em contrapartida, a conversão alimentar melhorou o aumento dos níveis de EMAn. O consumo de EMAn é constante independentemente do seu nível dietético. Não há diferença nas unidades Haugh, nos sólidos da gema e na porcentagem dos componentes do ovo. O peso específico melhora com o aumento dos níveis de EMAn. Os níveis nutricionais para poedeiras velhas podem estar sendo superestimados.
A total of 1200 Lohmann LSL laying hens, with 64 weeks of age in conventional cages was used. These were divided into five groups according to the level of apparent metabolizable energy corrected for nitrogen retention (AMEn) present in the diet: 2700kcal/kg; 2775kcal/kg; 2850kcal/kg; 2925kcal/kg and 3000kcal/kg, with six replicates. The birds received the diets based on corn and soybean meal for 16 weeks. The experimental design was completely randomized and the means were submitted to polynomial regression and the Kruskal-Wallis test. The increased level of AMEn had no effect on production, egg mass and weight. There was no influence of AMEn on bird weight, egg weight and viability. Feed intake decreased with increasing levels, however, and the conversion of AMEn was worse with its increase, and in return feed conversion worsened with increasing consumption. AMEn is constant regardless of the level of the feed. There is no difference in Haugh units, yolk solids and percentage of egg components. The specific gravity improves with increasing levels of AMEn. The nutritional levels for older laying hens may be overestimated.
Asunto(s)
Animales , Pollos/crecimiento & desarrollo , Pollos/fisiología , Pollos/metabolismo , Proteínas del Huevo/análisisRESUMEN
Most studies in nutrition for the South American catfish (surubim) were limited to the initial phase of development. However, it is clear that performance and nutrient utilization can change during the life stages of a fish. Therefore, this study aimed to evaluate the performance and nutrient utilization in juveniles of surubim fed diets varying in protein and energy levels. Two experiments were performed to test different levels of energy and protein in formulated diets. In the first experiment, surubim juveniles (89.2±4.8g) were fed five diets containing different levels of energy (18.0, 18.8, 19.6, 20.5, 21.3 MJ/kg). In the second experiment, juveniles (170.03±3.35g) were fed five diets containing different levels of protein (360, 400, 440, 480 and 520g/kg). The most favorable energy level for weight gain was 20.3 MJ/kg. The increasing energy levels provided a rise in fat and decrease in protein whole-body composition. The protein amount was between 360 to 400g/kg (383g/kg), which was adequate for performance and nutrient assimilation in surubim juveniles.
A maior parte dos estudos a respeito dos aspectos nutricionais do surubim está limitada às primeiras fases de desenvolvimento. Entretanto, é claro que o desempenho e a utilização dos nutrientes podem mudar durante os diferentes estágios de desenvolvimento destes animais. Assim sendo, este estudo teve como objetivo avaliar o desempenho e a utilização de nutrientes em juvenis de surubim alimentados com dietas contendo níveis variáveis de energia e proteína. Dois experimentos foram realizados para testar os diferentes níveis de proteína e energia. No primeiro experimento, juvenis de surubim (89,2±4,8g) foram alimentados com cinco dietas contendo níveis diferentes de energia (18.0, 18.8, 19.6, 20.5, 21.3MJ/kg). No segundo experimento, os juvenis (170,03±3,35g) foram alimentados com dietas contendo cinco níveis de proteína (360, 400, 440, 480 e 520g/kg). O melhor nível de energia para ganho de peso foi 20,3 MJ/kg. O aumento dos níveis de energia levou a um incremento nos níveis de lipídeo e diminuição da proteína corporal. Níveis de proteína entre 360 a 400g/kg foram os mais adequados para o desempenho e utilização dos nutrientes em juvenis grandes de surubim.
Asunto(s)
Animales , Análisis de Secuencia de Proteína/veterinaria , Fenómenos Fisiológicos Nutricionales de los Animales/fisiología , Peces/anatomía & histología , Peces/clasificación , Peces/genéticaRESUMEN
AIMS/HYPOTHESIS: Supervised exercise programmes improve glycaemic control in type 2 diabetes, but training characteristics associated with reduction in HbA(1c) remain unclear. We conducted a systematic review with meta-regression analysis of randomised clinical trials (RCTs) assessing the association between intensity and volume of exercise training (aerobic, resistance or combined) and HbA(1c) changes in patients with type 2 diabetes. METHODS: Five electronic databases were searched (1980-2012) to retrieve RCTs of at least 12 weeks' duration, consisting of supervised exercise training vs no intervention, that reported HbA(1c) changes and exercise characteristics. Two independent reviewers conducted study selection and data extraction. RESULTS: Twenty-six RCTs (2,253 patients) met the inclusion criteria. In multivariate analysis, baseline HbA(1c) and exercise frequency explained nearly 58% of between-study variance. Baseline HbA(1c) was inversely correlated with HbA(1c) reductions after the three types of exercise training. In aerobic training, exercise volume (represented by frequency of sessions) was associated with changes in HbA(1c) (weighted r = -0.64), while no variables were correlated with glycaemic control induced by resistance training. In combined training, weekly volume of resistance exercise explained heterogeneity in multivariate analysis and was associated with changes in HbA(1c) levels (weighted r = -0.70). CONCLUSIONS/INTERPRETATION: Reduction in HbA(1c) is associated with exercise frequency in supervised aerobic training, and with weekly volume of resistance exercise in supervised combined training. Therefore, exercise volume is a major determinant of glycaemic control in patients with type 2 diabetes.
Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Ejercicio Físico/fisiología , HumanosRESUMEN
The predators Hippodamia convergens Guérin-Menéville (Coleoptera: Coccinelidae) and Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae), are frequently observed on vegetable crops, especially on tomato plants, as well as on flowers of several plants around crop fields. It is well known that when predators feed on pollen and nectar they can increase their longevity and reproductive capacity. The objective of this work was to identify plants that could be a pollen source for H. convergens and C. externa in order to develop strategies to attract and keep these predators in vegetable fields like the tomato crop. Adults of C. externa (53 individuals) and H. convergens (43 individuals) were collected in fields from 2004-2005 at Embrapa Hortaliças, Brasília, Federal District. The insects were processed by the acetolysis method and pollen from them was extracted and identified. A total of 11335 grains of pollen belonging to 21 families were extracted from C. externa. A total of 46 pollen grains belonging to ten families were extracted from H. convergens. The Poaceae family was the most abundant one for C. externa while Asteraceae was the commonest pollen for H. convergens. The importance of pollen from different plant species as a food resource for each predator species gives an indication of the importance of plant community structure inside and around crop fields for the establishment of these predator populations and to enhance conservation biological control.
Asunto(s)
Preferencias Alimentarias/fisiología , Insectos/fisiología , Magnoliopsida/clasificación , Polen/clasificación , Animales , Escarabajos/clasificación , Escarabajos/fisiología , Insectos/clasificación , Estaciones del AñoRESUMEN
Nephrogenic diabetes insipidus (NDI) is an inherited disorder characterized by renal resistance to the antidiuretic effect of arginine vasopressin (AVP), resulting in polyuria, polydipsia, and hypoosmolar urine. In the vast majority of cases, NDI is associated with germ-line mutations in the vasopressin receptor type 2 gene (AVPR2) and in about 8% of the cases with the water channel aquaporin-2 gene (AQP-2) mutations. To date, approximately 277 families with 185 germ-line mutations in the AVPR2 gene have been described worldwide. In the present study, the AVPR2 gene was genotyped in eight unrelated Brazilian kindred with NDI. In five of these NDI families, novel mutations were noted (S54R, I130L, S187R, 219delT, and R230P), whereas three seemingly unrelated probands were found to harbor previously described AVPR2 gene mutations (R106C, R137H, R337X). Additionally a novel polymorphism (V281V) was detected. In conclusion, although NDI is a rare disease, the findings of mutations scattered over the entire coding region of the AVPR2 gene are a valuable model to determine structure function relationship in G-protein-coupled receptor related diseases. Furthermore, our data indicate that in Brazil the spectrum of AVPR2 gene mutations is "family specific".