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BACKGROUND: Exercise training improves cardiometabolic outcomes in 'mean terms', but little information is available in children about the impact of the frequency/week and the wide inter-individual variability to exercise training reported in adults. OBJECTIVES: We compared the effects of resistance training (RT) and high-intensity interval training (HIT), and 'high' and 'low' frequency of training/week, for their effectiveness in decreasing insulin resistance (IR) levels in schoolchildren. A second aim was to decscribe and compare the prevalence of non-responders (NRs) between the different frequencies of training protocol. METHODS: Fifty-three schoolchildren with IR were randomly assigned into four groups: RT at high frequency (three times/week), HIT at high frequency, RT at a low frequency (two times/week) and HIT at low frequency. The intervention lasted 6 weeks. Blood samples and body composition, blood pressure and performance measurements were taken before and after the intervention. RESULTS: The prevalence of NRs was similar between the RTHF and HITHF (25.0% vs. 25.0%, P > 0.05) and RTLF and HITLF groups (20.0% vs. 46.6%, P = 0.174) for decreasing homeostasis model assessment of IR. However, significant differences in the prevalence of NRs were detected between RTHF and HITHF groups in fasting glucose (FGL) (18.7% vs. 58.3%, P < 0.031). CONCLUSIONS: Both RT and HIT improves the glucose control parameters in schoolchildren over 6 weeks, but only HIT is independent of a high or low frequency of training/week. The prevalence of NRs is similar for decreasing homeostasis model assessment of IR comparing each exercise mode in high vs. low frequency/week. However, both high- and low-frequency RT and HIT results in differences in the prevalence of NRs for FGL and other cardiometabolic and performance outcomes.
Assuntos
Glicemia/fisiologia , Terapia por Exercício/métodos , Exercício Físico/fisiologia , Resistência à Insulina/fisiologia , Adolescente , Pressão Sanguínea/fisiologia , Composição Corporal/fisiologia , Criança , Humanos , PrevalênciaRESUMO
[This corrects the article DOI: 10.1155/2017/9641392.].
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This study aimed to investigate the effect of heat stress and month of birth on growth performance, pelleted starter intake, and stress-related hormones in Holstein calves. Birth weight and growth records, representing 4735 Holstein calves from a large commercial dairy herd in northern Mexico (25° N; 22.3 °C mean annual temperature) from 2013 to 2015, were analyzed. Temperature-humidity index (THI) at calving, season of birth, and month of birth were the independent variables, whereas growth traits were the dependent variables. Increased THI at birth from < 65 to > 85 units was associated with a decrease in birth weight from 39.3 to 38.7 kg. Calves subjected to high THI (> 75 units) at calving showed lesser (P < 0.01) pre-weaning gains (405 ± 97 g/calf/day), whereas those calves born with THI < 70 units presented the highest gains (466 ± 112 g/calf/day). Birth during the fall months reduced (P < 0.01) weaning weight by about 5 kg compared with winter months. Also, the pre-weaning average daily gain for calves born in the fall was about 70 g less (P < 0.01) than calves delivered in winter months. Plasma triiodothyronine and tetraiodothyronine levels were lower (1.02 ± 0.21 and 48 ± 7.9 ng/mL, respectively; P < 0.01) in summer and highest in winter (1.64 ± 0.48 and 66 ± 11 ng/mL, respectively). Mean plasma cortisol concentration was higher in heat-stressed calves born in summer (59 ± 40 ng/mL) than calves born in winter (20 ± 28 ng/mL). Pelleted starter intake 1 week before weaning was lowest (P < 0.01) in the fall (0.82 ± 0.26 kg/calf/day; mean ± SD) and highest in spring (1.26 ± 0.43 kg/calf/day). It was concluded that in this particular environment, heat stress affects birth weight and growth rate of Holstein calves. Thus, environmental management of the newborn calf during hot spring and summer months is warranted to optimize pelleted starter intake and calf growth rates.
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Doenças dos Bovinos , Transtornos de Estresse por Calor , Ração Animal , Animais , Peso Corporal , Bovinos/sangue , Bovinos/crescimento & desenvolvimento , Doenças dos Bovinos/sangue , Ingestão de Alimentos , Feminino , Transtornos de Estresse por Calor/sangue , Transtornos de Estresse por Calor/veterinária , Umidade , Hidrocortisona/sangue , Temperatura , DesmameRESUMO
This study describes four multiple nucleocapsid nucleopolyhedrovirus isolates recovered from infected larvae of beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae), on crops in two different geographical regions of Mexico. Molecular and biological characterization was compared with characterized S. exigua multiple nucleopolyhedrovirus (SeMNPV) isolates from the United States (SeUS1 and SeUS2) and Spain (SeSP2). Restriction endonuclease analysis of viral DNA confirmed that all Mexican isolates were SeMNPV isolates, but molecular differences between the Mexican and the reference isolates were detected using PCR combined with restriction fragment length polymorphism (RFLP). Amplification of the variable region V01 combined with RFLP distinguished the two Mexican isolates, SeSLP6 and SeSIN6. BglII digestions showed that the majority of the isolates contained submolar bands, indicating the presence of genetic heterogeneity. Amplification of the variable regions V04 and V05 distinguished between American and the Spanish isolates. Biological characterization was performed against two laboratory colonies of S. exigua, one from Mexico, and another from Switzerland. Insects from the Mexican colony were less susceptible to infection than insects from Se-Swiss colony. In the Se-Mex colony, SeSP2 was the most pathogenic isolate followed by SeSIN6, although their virulence was similar to most of the isolates tested. In Se-Swiss colony, similar LD50 values were observed for the five isolates, although the virulence was higher for the SeSLP6 isolate, which also had the highest OB (occlusion body) yield. We conclude that the Mexican isolates SeSIN6 and SeSLP6 possess insecticidal traits of value for the development of biopesticides for the control of populations of S. exigua.
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DNA Viral/genética , Nucleopoliedrovírus/fisiologia , Controle Biológico de Vetores , Spodoptera/virologia , Animais , Larva/crescimento & desenvolvimento , Larva/virologia , México , Nucleopoliedrovírus/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Spodoptera/crescimento & desenvolvimentoRESUMO
Parkinson's disease (PD) is a neurodegenerative condition, which compromises the motor functions and causes the alteration of some executive brain functions. The presence of changes in cognitive symptoms in PD could be due to the procedure of deep brain stimulation (DBS). We searched in several databases for studies that compared performance in executive function tests before and after the DBS procedure in PE and then performed a meta-analysis. After the initial search, there were 15 articles that specifically evaluated the functions of verbal fluency, working memory, cognitive flexibility, abstract thinking, and inhibition. It was found that there were differences in the evaluation of the cognitive functions in terms of the protocols, which generated heterogeneity in the results of the meta-analysis. Likewise, a tendency to diminish functions like verbal fluency and inhibition was found, being this consistent with similar studies. In the other functions evaluated, no difference was found between pre- and postsurgery scores. Monitoring of this type of function is recommended after the procedure.
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After a traumatic injury to the central nervous system, the distal stumps of axons undergo Wallerian degeneration (WD), an event that comprises cytoskeleton and myelin breakdown, astrocytic gliosis, and overexpression of proteins that inhibit axonal regrowth. By contrast, injured neuronal cell bodies show features characteristic of attempts to initiate the regenerative process of elongating their axons. The main molecular event that leads to WD is an increase in the intracellular calcium concentration, which activates calpains, calcium-dependent proteases that degrade cytoskeleton proteins. The aim of our study was to investigate whether preventing axonal degeneration would impact the survival of retinal ganglion cells (RGCs) after crushing the optic nerve. We observed that male Wistar rats (weighing 200-400 g; n=18) treated with an exogenous calpain inhibitor (20 mM) administered via direct application of the inhibitor embedded within the copolymer resin Evlax immediately following optic nerve crush showed a delay in the onset of WD. This delayed onset was characterized by a decrease in the number of degenerated fibers (P<0.05) and an increase in the number of preserved fibers (P<0.05) 4 days after injury. Additionally, most preserved fibers showed a normal G-ratio. These results indicated that calpain inhibition prevented the degeneration of optic nerve fibers, rescuing axons from the process of axonal degeneration. However, analysis of retinal ganglion cell survival demonstrated no difference between the calpain inhibitor- and vehicle-treated groups, suggesting that although the calpain inhibitor prevented axonal degeneration, it had no effect on RGC survival after optic nerve damage.
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Axônios/efeitos dos fármacos , Glicoproteínas/farmacologia , Traumatismos do Nervo Óptico/tratamento farmacológico , Polivinil/farmacologia , Células Ganglionares da Retina/efeitos dos fármacos , Degeneração Walleriana/tratamento farmacológico , Animais , Axônios/patologia , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Imuno-Histoquímica , Masculino , Microscopia Eletrônica de Transmissão , Compressão Nervosa , Traumatismos do Nervo Óptico/patologia , Ratos Wistar , Células Ganglionares da Retina/patologia , Fatores de Tempo , Resultado do Tratamento , Degeneração Walleriana/patologiaRESUMO
After a traumatic injury to the central nervous system, the distal stumps of axons undergo Wallerian degeneration (WD), an event that comprises cytoskeleton and myelin breakdown, astrocytic gliosis, and overexpression of proteins that inhibit axonal regrowth. By contrast, injured neuronal cell bodies show features characteristic of attempts to initiate the regenerative process of elongating their axons. The main molecular event that leads to WD is an increase in the intracellular calcium concentration, which activates calpains, calcium-dependent proteases that degrade cytoskeleton proteins. The aim of our study was to investigate whether preventing axonal degeneration would impact the survival of retinal ganglion cells (RGCs) after crushing the optic nerve. We observed that male Wistar rats (weighing 200-400 g; n=18) treated with an exogenous calpain inhibitor (20 mM) administered via direct application of the inhibitor embedded within the copolymer resin Evlax immediately following optic nerve crush showed a delay in the onset of WD. This delayed onset was characterized by a decrease in the number of degenerated fibers (P<0.05) and an increase in the number of preserved fibers (P<0.05) 4 days after injury. Additionally, most preserved fibers showed a normal G-ratio. These results indicated that calpain inhibition prevented the degeneration of optic nerve fibers, rescuing axons from the process of axonal degeneration. However, analysis of retinal ganglion cell survival demonstrated no difference between the calpain inhibitor- and vehicle-treated groups, suggesting that although the calpain inhibitor prevented axonal degeneration, it had no effect on RGC survival after optic nerve damage.
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Animais , Masculino , Polivinil/farmacologia , Células Ganglionares da Retina/efeitos dos fármacos , Axônios/efeitos dos fármacos , Degeneração Walleriana/tratamento farmacológico , Glicoproteínas/farmacologia , Traumatismos do Nervo Óptico/tratamento farmacológico , Axônios/patologia , Imuno-Histoquímica , Sobrevivência Celular/efeitos dos fármacos , Resultado do Tratamento , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Ratos Wistar , Traumatismos do Nervo Óptico/patologia , Microscopia Eletrônica de Transmissão , Compressão NervosaRESUMO
Little is known about local Criollo pig genetic resources and relationships among the various populations. In this paper, genetic diversity and relationships among 17 Criollo pig populations from 11 American countries were assessed with 24 microsatellite markers. Heterozygosities, F-statistics, and genetic distances were estimated, and multivariate, genetic structure and admixture analyses were performed. The overall means for genetic variability parameters based on the 24 microsatellite markers were the following: mean number of alleles per locus of 6.25 ± 2.3; effective number of alleles per locus of 3.33 ± 1.56; allelic richness per locus of 4.61 ± 1.37; expected and observed heterozygosity of 0.62 ± 0.04 and 0.57 ± 0.02, respectively; within-population inbreeding coefficient of 0.089; and proportion of genetic variability accounted for by differences among breeds of 0.11 ± 0.01. Genetic differences were not significantly associated with the geographical location to which breeds were assigned or their country of origin. Still, the NeighborNet dendrogram depicted the clustering by geographic origin of several South American breeds (Criollo Boliviano, Criollo of northeastern Argentina wet, and Criollo of northeastern Argentina dry), but some unexpected results were also observed, such as the grouping of breeds from countries as distant as El Salvador, Mexico, Ecuador, and Cuba. The results of genetic structure and admixture analyses indicated that the most likely number of ancestral populations was 11, and most breeds clustered separately when this was the number of predefined populations, with the exception of some closely related breeds that shared the same cluster and others that were admixed. These results indicate that Criollo pigs represent important reservoirs of pig genetic diversity useful for local development as well as for the pig industry.
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Cruzamento/métodos , Repetições de Microssatélites/genética , Suínos/genética , Alelos , América , Animais , Variação Genética/genética , HeterozigotoRESUMO
The Uruguayan Creole cattle population (N = 600) is located in a native habitat in south-east Uruguay. We analyzed its genetic diversity and compared it to other populations of American Creole cattle. A random sample of 64 animals was genotyped for a set of 17 microsatellite loci, and the D-loop hyper-variable region of mtDNA was sequenced for 28 calves of the same generation. We identified an average of 5.59 alleles per locus, with expected heterozygosities between 0.466 and 0.850 and an expected mean heterozygosity of 0.664. The polymorphic information content ranged from 0.360 to 0.820, and the global FIS index was 0.037. The D-loop analysis revealed three haplotypes (UY1, UY2 and UY3), belonging to the European matriline group, with a haplotype diversity of 0.532. The history of the population, changes in the effective population size, bottlenecks, and genetic drift are possible causes of the genetic variability patterns that we detected.
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DNA Mitocondrial/genética , Variação Genética , Repetições de Microssatélites/genética , Alelos , Animais , Cruzamento , Bovinos , Evolução Molecular , Frequência do Gene , Genética Populacional , Haplótipos , FilogeniaRESUMO
Peripheral-nerve injuries are a common clinical problem and often result in long-term functional deficits. Reconstruction of peripheral-nerve defects is currently undertaken with nerve autografts. However, there is a limited availability of nerves that can be sacrificed and the functional recovery is never 100% satisfactory. We have previously shown that gene therapy with vascular endothelial growth factor (VEGF) significantly improved nerve regeneration, neuronal survival, and muscle activity. Our hypothesis is that granulocyte colony-stimulating factor (G-CSF) synergizes with VEGF to improve the functional outcome after sciatic nerve transection. The left sciatic nerves and the adjacent muscle groups of adult mice were exposed, and 50 or 100 µg (in 50 µl PBS) of VEGF and/or G-CSF genes was injected locally, just below the sciatic nerve, and transferred by electroporation. The sciatic nerves were transected and placed in an empty polycaprolactone (PCL) nerve guide, leaving a 3-mm gap to challenge nerve regeneration. After 6 weeks, the mice were perfused and the sciatic nerve, the dorsal root ganglion (DRG), the spinal cord and the gastrocnemius muscle were processed for light and transmission electron microscopy. Treated animals showed significant improvement in functional and histological analyses compared with the control group. However, the best results were obtained with the G-CSF+VEGF-treated animals: quantitative analysis of regenerated nerves showed a significant increase in the number of myelinated fibers and blood vessels, and the number of neurons in the DRG and motoneurons in the spinal cord was significantly higher. Motor function also showed that functional recovery occurred earlier in animals receiving G-CSF+VEGF-treatment. The gastrocnemius muscle showed an increase in weight and in the levels of creatine phosphokinase, suggesting an improvement of reinnervation and muscle activity. These results suggest that these two factors acted synergistically and optimized the nerve repair potential, improving regeneration after a transection lesion.