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1.
Trop Anim Health Prod ; 56(7): 231, 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39096397

RESUMEN

The objective of this study was to evaluate the economic and financial viability of finishing of two sexes of Brazilian Somalis sheep in feedlot receiving diets with 0 and 15% reduction in the total digestible nutrients and crude protein contents. A completely randomized design was adopted, in a 2 × 2 factorial arrangement, with treatments consisting of two sexes (non-castrated males (21.13 ± 5.00 kg) and females (17.99 ± 3.79 kg) and two diets (0 and 15% reduction in the levels of total digestible nutrients and crude protein). Four simulations of productive scenarios were carried out: non-castrated males receiving the diet with 0% reduction; non-castrated males receiving the diet with 15% reduction; females receiving the diet with 0% reduction and females receiving the diet with 0% reduction, for a period of 70 days in feedlot. The highest costs of the system were with feeding and other costs, mainly the acquisition of animals. For both sexes, the 0% reduction diet showed the highest total cost, total revenue, break-even point. Non-castrated males fed a non-reduced diet and females fed a 15% reduction diet had higher net income, rate of return, total productivity, net present value, internal rate of return, profitability index and profitability rate. Less favorable situations were not profitable for any scenario. However, the increase in sales price favorability makes the activity viable. The reduction of total digestible nutrients and crude protein affects the economic and financial viability of Brazilian Somalis sheep. For non-castrated males it is recommended the diet without reduction and for females the diet with 15% reduction of nutrients.


Asunto(s)
Alimentación Animal , Crianza de Animales Domésticos , Fenómenos Fisiológicos Nutricionales de los Animales , Dieta , Animales , Masculino , Femenino , Brasil , Alimentación Animal/análisis , Alimentación Animal/economía , Crianza de Animales Domésticos/economía , Crianza de Animales Domésticos/métodos , Dieta/veterinaria , Dieta/economía , Oveja Doméstica/fisiología , Oveja Doméstica/crecimiento & desarrollo
2.
Int J Mol Sci ; 24(20)2023 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-37894781

RESUMEN

68Ga-based radiopharmaceuticals are routinely used for PET imaging of multiple types of tumors. Gallium-68 is commonly obtained from 68Ge/68Ga generators, which are limited in the quantity of activity produced. Alternatively, gallium-68 can easily be produced on a cyclotron using liquid targets. In this study, we optimized the GMP production of [68Ga]GaFAPI-46 using gallium-68 produced via a standard medical cyclotron using liquid targets. Starting from the published synthesis and quality control procedures described for other 68Ga-based radiopharmaceuticals, we have validated the synthesis process and the analytical methods to test the quality parameters of the final product to be used for routine clinical studies. [68Ga]GaFAPI-46 was successfully produced with high radiochemical purity and yield using an IBA Synthera® Extension module. Gallium chloride was produced on a medical cyclotron using a liquid target with activity of 4.31 ± 0.36 GBq at the end of purification (EOP). Analytical methods were established and validated, meeting Ph. Eur. standards. Full GMP production was also validated in three consecutive batches, producing 2.50 ± 0.46 GBq of [68Ga]GaFAPI-46 at the end of synthesis (EOS), with 98.94 ± 0.72% radiochemical purity measured via radio-HPLC. Quality was maintained for up to 3 h after the EOS. Production of [68Ga]GaFAPI-46 was performed and validated using a standard medical cyclotron with liquid targets. The quality control parameters (e.g., sterility, purity, and residual solvents) conformed to Ph. Eur. and a shelf life of 3 h was established. The activity of [68Ga]GaFAPI-46 produced was substantially higher than the one obtained with generators, enabling a better response to the clinical need for this radiopharmaceutical.


Asunto(s)
Radioisótopos de Galio , Radiofármacos , Ciclotrones , Tomografía de Emisión de Positrones
3.
Trop Anim Health Prod ; 53(3): 359, 2021 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-34125303

RESUMEN

The objective of this study was to evaluate the metabolic profile of Santa Inês ewe lambs fed diets for early or late-maturing diets with or without nutrient restrictions. The experiment consisted of a 2 × 2 completely randomized factorial experiment with either early- or late-maturity feed formulation according to "Nutrient Requirements of Small Ruminants" with or without 15% crude protein (CP) and total digestible nutrients (TDN) restrictions in diets formulated, five replications, and 20 ewe lambs averaging 15.1±2.6 kg. Lambs on early-maturity diets consumed greater (P<0.05) dietary ether extract (EE), non-fibrous carbohydrates, and TDN than those on late-maturity diets. Lambs on early-maturity diets had 7.11% greater dry matter digestibility (DMD) compared to lambs fed late-maturity diets. Lambs fed late-maturity diets, in general, had greater intake (IN), excreted (EN), and retained (RN) N as well as greater RN/IN and EN/IN ratios. There were no differences in blood total protein or albumin among lambs fed for different finishing maturity targets. Diets designed for late-maturing lambs resulted in greater microbial N and CP as well as rumen and metabolizable, degradable, and undegradable rumen and metabolizable CP. The selection of diets for early or late maturity carcasses depends on the production system goals. Diets without restrictions are recommended for early-maturity carcass finishing while diets with 15% CP and TDN restriction are recommend for late-maturity finishing.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Digestión , Alimentación Animal/análisis , Animales , Dieta/veterinaria , Femenino , Metaboloma , Nutrientes , Rumen , Ovinos , Oveja Doméstica , Destete
4.
Eur J Appl Physiol ; 120(5): 1097-1109, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32212025

RESUMEN

PURPOSE: This study aims to analyze swimmers' oxygen uptake kinetics ([Formula: see text]K) and bioenergetic profiles in 50, 100, and 200 m simulated swimming events and determine which physiological variables relate with performance. METHODS: Twenty-eight well-trained swimmers completed an incremental test for maximal oxygen uptake (Peak-[Formula: see text]) and maximal aerobic velocity (MAV) assessment. Maximal trials (MT) of 50, 100, and 200-m in front crawl swimming were performed for [Formula: see text]K and bioenergetic profile. [Formula: see text]K parameters were calculated through monoexponential modeling and by a new growth rate method. The recovery phase was used along with the blood lactate concentration for bioenergetics profiling. RESULTS: Peak-[Formula: see text] (57.47 ± 5.7 ml kg-1 min-1 for male and 53.53 ± 4.21 ml kg-1 min-1 for female) did not differ from [Formula: see text]peak attained at the 200-MT for female and at the 100 and 200-MT for male. From the 50-MT to 100-MT and to the 200-MT the [Formula: see text]K presented slower time constants (8.6 ± 2.3 s, 11.5 ± 2.4 s and 16.7 ± 5.5 s, respectively), the aerobic contribution increased (~ 34%, 54% and 71%, respectively) and the anaerobic decreased (~ 66%, 46% and 29%, respectively), presenting a cross-over in the 100-MT. Both energy systems, MAV, Peak-[Formula: see text], and [Formula: see text] peak of the MT's were correlated with swimming performance. DISCUSSION: The aerobic energy contribution is an important factor for performance in 50, 100, and 200-m, regardless of the time taken to adjust the absolute oxidative response, when considering the effect on a mixed-group regarding sex. [Formula: see text]K speeding could be explained by a faster initial pacing strategy used in the shorter distances, that contributed for a more rapid increase of the oxidative contribution to the energy turnover.


Asunto(s)
Metabolismo Energético/fisiología , Consumo de Oxígeno , Oxígeno/metabolismo , Desempeño Psicomotor/fisiología , Natación/fisiología , Adolescente , Femenino , Humanos , Cinética , Ácido Láctico/sangre , Masculino
5.
Trop Anim Health Prod ; 52(4): 2111-2117, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32065335

RESUMEN

Contagious agalactia is a disease caused by Mycoplasma agalactiae that leads to a reduction or complete stop of milk production. Caprine arthritis encephalitis (CAE) is an infectious disease caused by a lentivirus of the Retroviridae family, member of the small ruminant lentivirus (SRLV) group. Although these diseases are caused by distinct pathogens, the clinical presentation is similar. Hence, this study aimed to perform a serological investigation, as well as to assess correlation between both diseases and risk factors associated in two mesoregions of Rio Grande do Norte, Brazil. Enzyme-linked immunosorbent assay (ELISA) was used for contagious agalactia and western blot for CAE. A total of 538 serum samples were used in this study that were collected from goats and sorted from a blood bank of the Brazilian Agricultural Research Corporation. Seroprevalence of M. agalactiae in flocks from Rio Grande do Norte was 7.8% (42/538). In both regions that were investigated, 25.9% (14/54) of farms had positive animals. CAE results revealed that 3.9% (21/538) of animals and 42.6% (23/54) of farms had this disease. Concerning risk factors, only sex and animal category presented significant relevance (P < 0.05) for contagious agalactia, in which females presented higher frequency of seropositive individuals (10.1%; 39/387). In the animal category, 4.3% (14/326) and 11.1% (36/323) of female breeders were positive for CAE and contagious agalactia, respectively, and significance was identified only in the latter (P < 0.05). In conclusion, there was no correlation between the investigated diseases, considering that no animal demonstrated antibodies for both pathogens.


Asunto(s)
Virus de la Artritis-Encefalitis Caprina/aislamiento & purificación , Enfermedades de las Cabras/epidemiología , Infecciones por Lentivirus/veterinaria , Infecciones por Mycoplasma/veterinaria , Mycoplasma agalactiae/aislamiento & purificación , Animales , Brasil/epidemiología , Coinfección , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Enfermedades de las Cabras/microbiología , Cabras , Infecciones por Lentivirus/complicaciones , Infecciones por Lentivirus/epidemiología , Masculino , Infecciones por Mycoplasma/complicaciones , Infecciones por Mycoplasma/epidemiología , Factores de Riesgo , Estudios Seroepidemiológicos
6.
Trop Anim Health Prod ; 52(4): 1945-1952, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31970632

RESUMEN

The objective of this study was to determine the frequency of seropositivity Corynebacterium pseudotuberculosis in sheep in five states of northeastern Brazil, using an indirect enzyme-linked immunosorbent assay (i-ELISA). Young and adult sheep of both sexes were used. Blood samples were collected from 2638 sheep from 223 herds across all states. For the i-ELISA, antigens produced from the strain of C. pseudotuberculosis BRM 029971, a bacterial isolate from the Northeast region of Brazil, were used. Sensitivity and specificity indexes were calculated for the validation of the test, using as reference 49 and 134 serum samples from sheep known to be positive and negative, respectively. The i-ELISA presented four false-negative and four false-positive results, showing a specificity of 97.01%, a sensitivity of 91.84%, and an accuracy of 95.63%. These results were calculated based on an optical density (OD) cutoff point = 0.138. Of the 2638 sheep tested, 996 (37.76%, 95% CI = 35.93-39.62%) were seropositive, and of the 223 evaluated herds, 210 (94.17%, 95% CI = 90.28-96.56%) seropositive. The i-ELISA showed adequate sensitivity and specificity, proving to be a useful tool in the diagnosis of caseous lymphadenitis (CLA) in sheep. Infection by C. pseudotuberculosis, determined by serology, is disseminated in the sheep herds in the states of Northeast Brazil. Thus, there is a need to implement effective control measures that prevent the spread of infectious agents.


Asunto(s)
Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis/aislamiento & purificación , Linfadenitis/veterinaria , Enfermedades de las Ovejas/epidemiología , Animales , Brasil/epidemiología , Infecciones por Corynebacterium/epidemiología , Infecciones por Corynebacterium/microbiología , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Linfadenitis/epidemiología , Linfadenitis/microbiología , Masculino , Prevalencia , Sensibilidad y Especificidad , Estudios Seroepidemiológicos , Ovinos , Enfermedades de las Ovejas/microbiología , Oveja Doméstica
7.
Parasite Immunol ; 41(4): e12613, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30582754

RESUMEN

This study's purpose was to identify polymorphisms (SNP) in the goat ß-defensin 1 gene and to associate these SNPs with traits related to nematodean and protozoan infections in Anglo-Nubian goats from semiarid region of Brazil. A total of 184 animals were used for DNA extraction, PCR and DNA automatic sequencing. The association analyses included the fixed effects of animal age, bloodline and genotype of the SNP marker in the statistical model. The means of genotypes were compared by the Fisher test (P < 0.05). Twelve polymorphism genotypes were found: two in intron 1, seven in exon 2 and three in 3' untranslated region. The SNPs of exon 2 were responsible for amino acid substitutions in six genetic codes, and the changes in the 25th and 33rd codes affected the protein function. The SNP 1937 was significantly associated with number of protozoan oocysts, whereas SNP 2001 was associated with degree of anaemia (Famacha©). Polymorphism 2046, in turn, showed a significant association with Famacha© degree and number of protozoan oocysts. SNP 2140 associated with maximum EPG of the animal. Results from this study suggest that the ß-defensin 1 gene can be used as a molecular marker for selection of goats regarding the susceptibility to endoparasites infections.


Asunto(s)
Cabras/genética , Cabras/parasitología , Nematodos/clasificación , Infecciones Protozoarias en Animales/parasitología , beta-Defensinas/genética , Sustitución de Aminoácidos/genética , Animales , Secuencia de Bases , Brasil , Heces/parasitología , Femenino , Predisposición Genética a la Enfermedad/genética , Genotipo , Nematodos/aislamiento & purificación , Polimorfismo de Nucleótido Simple/genética , Análisis de Secuencia de ADN
8.
J Sports Sci ; 37(17): 2037-2044, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31079555

RESUMEN

Leucine metabolites may reduce training-induced inflammation; however, there is scant evidence for this assertion. We conducted a double-blind randomized controlled pragmatic trial where 40 male participants were allocated into 4 groups: α-hydroxyisocaproic acid group ([α-HICA], n = 10, Fat-free mass [FFM] = 62.0 ± 7.1 kg), ß-hydroxy-ß-methylbutyrate free acid group ([HMB-FA], n = 11, FFM = 62.7 ± 10.5 kg), calcium ß-hydroxy-ß-methylbutyrate group ([HMB-Ca], n = 9, FFM = 65.6 ± 10.1 kg) or placebo group ([PLA]; n = 10, FFM = 64.2 ± 5.7 kg). An 8-week whole-body resistance training routine (3 training sessions per week) was employed to induce gains in skeletal-muscle thickness. Skeletal muscle thickness (MT), one repetition maximum (1RM), interleukin-6 (IL-6), high-sensitivity C-reactive protein (hsCRP) and tumour necrosis factor alpha (TNF-α) were assessed at baseline and at the end of weeks 4 and 8. Time-dependent increases were detected from baseline to week 8 for MT (vastus lateralis: p = 0.009; rectus femoris: p = 0.018), 1RM (back squat: α-HICA, 18.5% ± 18.9%; HMB-FA, 23.2% ± 16%; HMB-Ca, 10.5% ± 13.8%; PLA, 19.7% ± 9% and bench press: α-HICA, 13.8% ± 19.1%; HMB-FA, 15.5% ± 9.3%; HMB-Ca, 10% ± 10.4%; PLA, 14.4 ± 11.3%, both p < 0.001), IL-6, hsCRP (both p < 0.001) and TNF-α (p = 0.045). No differences were found between groups at any time point. No leucine metabolite attenuated inflammation during training. Additionally, backwards elimination regressions showed that no circulating inflammatory marker consistently shared variance with the change in any outcome. Using leucine metabolites to modulate inflammation cannot be recommended from the results obtained herein. Furthermore, increases in inflammatory markers, from training, do not correlate with any outcome variable and are likely the result of training adaptations.


Asunto(s)
Caproatos/administración & dosificación , Inflamación/sangre , Leucina/metabolismo , Entrenamiento de Fuerza , Fenómenos Fisiológicos en la Nutrición Deportiva , Valeratos/administración & dosificación , Adulto , Biomarcadores/sangre , Composición Corporal , Proteína C-Reactiva/análisis , Calcio , Suplementos Dietéticos , Método Doble Ciego , Humanos , Interleucina-6/sangre , Masculino , Fuerza Muscular , Músculo Esquelético/crecimiento & desarrollo , Músculo Esquelético/fisiología , Factor de Necrosis Tumoral alfa/sangre , Adulto Joven
9.
Trop Anim Health Prod ; 51(4): 745-752, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30421374

RESUMEN

Goat breeding in the Northeast region of Brazil plays an important socioeconomic role. However, there are significant losses caused by sanitary deficits and infectious diseases, particularly caseous lymphadenitis (CL). Although CL is considered endemic in Northeastern Brazil, a comprehensive and up-to-date study of this disease in goat herds in this region is necessary. The objective of this study was to determine the farm-level and animal-level seroprevalences for the disease and to identify the possible risk factors that characterize CL in the caprine species of five Northeastern's states (Ceará, Piauí, Rio Grande do Norte, Paraíba, and Sergipe). A total of 2744 goat serum samples from 230 farms were collected between 2010 and 2012. The diagnosis of Corynebacterium pseudotuberculosis infection was performed using the indirect ELISA technique. Farm-level and animal-level seroprevalences were 87.8% and 30.3%, respectively, suggesting that C. pseudotuberculosis is widespread in goat herds of the Northeast region. The risk factors were as follows: absence of forage silage (odds ratio = 5.39), not separating animals by sex (odds ratio = 4.16) or by age (odds ratio = 6.30), not replacing old goat breeders (odds ratio = 7.80), and non-treatment of CL lumps prior to spontaneous rupture (odds ratio = 10.34). This study supports the idea that caseous lymphadenitis is widely disseminated in goats from Northeastern Brazil and based on the risk factor analysis attention should be given to the need to establish adequate control measures, such as incision and early drainage of superficial abscesses, quarantine and elimination of affected animals, periodic inspection of the herd, non-introduction of infected animals, and early disposal of animals with recurrent CL.


Asunto(s)
Crianza de Animales Domésticos , Infecciones por Corynebacterium/veterinaria , Corynebacterium pseudotuberculosis/aislamiento & purificación , Enfermedades de las Cabras/epidemiología , Linfadenitis/veterinaria , Animales , Brasil/epidemiología , Infecciones por Corynebacterium/epidemiología , Demografía , Ensayo de Inmunoadsorción Enzimática/veterinaria , Enfermedades de las Cabras/sangre , Cabras , Linfadenitis/epidemiología , Factores de Riesgo , Estudios Seroepidemiológicos
10.
Eur J Appl Physiol ; 118(3): 573-583, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29313111

RESUMEN

PURPOSE: Long-term training influence on athletes' immune cell response to acute exercise has been poorly studied, despite the complexity of both chronic and acute adaptations induced by training. The purpose of the study is to study the influence of a 4-month swimming training cycle on the immune cell response to a high-intensity training session, during 24 h of recovery, considering sex, maturity, and age group. METHODS: Forty-three swimmers (16 females, 14.4 ± 1.1 years; 27 males, 16.2 ± 2.0) performed a standardized high-intensity session, after the main competition of the first (M1), and second (M2) macrocycles. Blood samples were collected before (Pre), immediately after (Post), 2 h after (Post2h) and 24 h after (Post24h) exercise. Haemogram and lymphocytes subsets were assessed by an automatic cell counter and by flow cytometry, respectively. Subjects were grouped according to sex, competitive age groups, or pubertal Tanner stages. Results express the percentage of relative differences from Pre to Post, Post2h and Post24h. Upper respiratory symptoms (URS) and training load were quantified. RESULTS: At M2, we observed smaller increases of leukocytes (M1: 14.0 ± 36.3/M2: 2.33 ± 23.0%) and neutrophils (M1: 57.1 ± 71.6/M2: 38.9 ± 49.9%) at Post; and less efficient recoveries of total lymphocytes (M1: - 22.0 ± 20.1/M2: - 30.0 ± 18.6%) and CD19+ (M1: 4.09 ± 31.1/M2: - 19.1 ± 24.4%) at Post2h. At Post2h, the increment of CD4+/CD8+ was smaller in youth (M1: 21.5 ± 16.0/M2: 9.23 ± 21.4%), and bigger in seniors (M1: 3.68 ± 9.21/M2: 23.2 ± 15.0%); and at Post24h late pubertal swimmers' CD16+56+ recovered less efficiently (M1: - 0.66 ± 34.6/M2: - 20.5 ± 34.2%). CONCLUSIONS: The training cycle induced an attenuated immune change immediately after exercise and a less efficient recovery of total lymphocytes, involving an accentuated CD19+ decrease. The concomitant higher URS frequency suggests a potential immune depression and a longer interval of susceptibility to infection.


Asunto(s)
Entrenamiento de Intervalos de Alta Intensidad/métodos , Subgrupos Linfocitarios , Natación/fisiología , Adolescente , Femenino , Humanos , Masculino
11.
An Acad Bras Cienc ; 89(2): 1189-1203, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28640356

RESUMEN

Currently, there is a lack of studies on the correct utilization of continuous distributions for dry tropical forests. Therefore, this work aims to investigate the diameter structure of a brazilian tropical dry forest and to select suitable continuous distributions by means of statistic tools for the stand and the main species. Two subsets were randomly selected from 40 plots. Diameter at base height was obtained. The following functions were tested: log-normal; gamma; Weibull 2P and Burr. The best fits were selected by Akaike's information validation criterion. Overall, the diameter distribution of the dry tropical forest was better described by negative exponential curves and positive skewness. The forest studied showed diameter distributions with decreasing probability for larger trees. This behavior was observed for both the main species and the stand. The generalization of the function fitted for the main species show that the development of individual models is needed. The Burr function showed good flexibility to describe the diameter structure of the stand and the behavior of Mimosa ophthalmocentra and Bauhinia cheilantha species. For Poincianella bracteosa, Aspidosperma pyrifolium and Myracrodum urundeuva better fitting was obtained with the log-normal function.


Asunto(s)
Bosques , Dispersión de las Plantas/fisiología , Árboles/crecimiento & desarrollo , Clima Tropical , Anacardiaceae/crecimiento & desarrollo , Aspidosperma/crecimiento & desarrollo , Bauhinia/crecimiento & desarrollo , Biodiversidad , Brasil , Caesalpinia/crecimiento & desarrollo , Mapeo Geográfico , Mimosa/crecimiento & desarrollo , Valores de Referencia , Estadísticas no Paramétricas , Árboles/clasificación
12.
An Acad Bras Cienc ; 89(3): 1815-1828, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28954167

RESUMEN

Dry tropical forests are a key component in the global carbon cycle and their biomass estimates depend almost exclusively of fitted equations for multi-species or individual species data. Therefore, a systematic evaluation of statistical models through validation of estimates of aboveground biomass stocks is justifiable. In this study was analyzed the capacity of generic and specific equations obtained from different locations in Mexico and Brazil, to estimate aboveground biomass at multi-species levels and for four different species. Generic equations developed in Mexico and Brazil performed better in estimating tree biomass for multi-species data. For Poincianella bracteosa and Mimosa ophthalmocentra, only the Sampaio and Silva (2005) generic equation was the most recommended. These equations indicate lower tendency and lower bias, and biomass estimates for these equations are similar. For the species Mimosa tenuiflora, Aspidosperma pyrifolium and for the genus Croton the specific regional equations are more recommended, although the generic equation of Sampaio and Silva (2005) is not discarded for biomass estimates. Models considering gender, families, successional groups, climatic variables and wood specific gravity should be adjusted, tested and the resulting equations should be validated at both local and regional levels as well as on the scales of tropics with dry forest dominance.


Asunto(s)
Biomasa , Bosques , Brasil , Monitoreo del Ambiente , México , Modelos Estadísticos , Clima Tropical
13.
J Sports Sci ; 35(16): 1614-1621, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27602781

RESUMEN

The present study aimed to examine how high- and low-speed swimmers organise biomechanical, energetic and coordinative factors throughout extreme intensity swim. Sixteen swimmers (eight high- and eight low-speed) performed, in free condition, 100-m front crawl at maximal intensity and 25, 50 and 75-m bouts (at same pace as the previous 100-m), and 100-m maximal front crawl on the measuring active drag system (MAD-system). A 3D dual-media optoelectronic system was used to assess speed, stroke frequency, stroke length, propelling efficiency and index of coordination (IdC), with power assessed by MAD-system and energy cost by quantifying oxygen consumption plus blood lactate. Both groups presented a similar profile in speed, power output, stroke frequency, stroke length, propelling efficiency and energy cost along the effort, while a distinct coordination profile was observed (F(3, 42) = 3.59, P = 0.04). Speed, power, stroke frequency and propelling efficiency (not significant, only a tendency) were higher in high-speed swimmers, while stroke length and energy cost were similar between groups. Performing at extreme intensity led better level swimmers to achieve superior speed due to higher power and propelling efficiency, with consequent ability to swim at higher stroke frequencies. This imposes specific constraints, resulting in a distinct IdC magnitude and profile between groups.


Asunto(s)
Rendimiento Atlético/fisiología , Destreza Motora/fisiología , Natación/fisiología , Fenómenos Biomecánicos , Metabolismo Energético/fisiología , Humanos , Ácido Láctico/sangre , Masculino , Consumo de Oxígeno/fisiología , Estudios de Tiempo y Movimiento , Adulto Joven
14.
Malar J ; 14: 128, 2015 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-25890318

RESUMEN

BACKGROUND: The understanding of the mechanisms of immunity in malaria is crucial for the rational development of interventions such as vaccines. During blood stage infection, the spleen is considered to play critical roles in both immunity and immunopathology of Plasmodium falciparum infections. METHODS: Saimiri sciureus monkeys were inoculated with blood stages of P. falciparum (FUP strain) and spleens removed during acute disease (days 7 and 13 of infection) and during convalescence (15 days after start of chloroquine treatment). Cytokine (IFNγ, TNFα, IL2, IL6, IL10, and IL12) responses of splenocytes stimulated with P. falciparum-parasitized red blood cells were assessed by real-time PCR using specific Saimiri primers, and histological changes were evaluated using haematoxylin-eosin and Giemsa-stained slides. RESULTS: Early during infection (day 7, 1-2% parasitaemia), spleens showed disruption of germinal centre architecture with heavy B-cell activation (centroblasts), and splenocytes showed increased expression of IFNγ, IL6 and IL12 upon in vitro stimuli by P. falciparum-parasitized red blood cells (pRBC). Conversely, 15 days after treatment of blood stage infection with chloroquine, splenocytes showed spontaneous in vitro expression of TNFα, IL2, IL6, IL10, and IL12, but not IFNγ, and stimulation with P. falciparum pRBC blocked the expression of all these cytokines. During the acute phase of infection, splenic disarray with disorganized germinal centres was observed. During convalescence, spleens of the chloroquine-treated animals showed white pulp hyperplasia with extensive lymphocyte activation and persistency of heavily haemozoin-laden macrophages throughout the red pulp. CONCLUSIONS: Inability to eliminate haemozoin is likely involved in the persistent lymphocyte activation and in the anergic responses of Saimiri splenocytes to P. falciparum pRBC, with important negative impact in immune responses and implications for the design of malaria vaccine.


Asunto(s)
Citocinas/genética , Eritrocitos/parasitología , Malaria Falciparum/patología , Plasmodium falciparum/inmunología , Bazo/parasitología , Animales , Citocinas/metabolismo , Cartilla de ADN/genética , Modelos Animales de Enfermedad , Eritrocitos/citología , Humanos , Malaria Falciparum/parasitología , Parasitemia/parasitología , Parasitemia/patología , Reacción en Cadena en Tiempo Real de la Polimerasa , Saimiri , Bazo/patología
15.
J Strength Cond Res ; 29(10): 2836-43, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25148466

RESUMEN

The purpose of this study was to understand the ventilatory and physiological responses immediately below and above the maximal lactate steady-state (MLSS) velocity and to determine the relationship of oxygen uptake (VO2) kinetics parameters with performance, in swimmers. Competitive athletes (N = 12) completed in random order and on different days a 400-m all-out test, an incremental step test comprising 5 × 250- and 1 × 200-m stages and 30 minutes at a constant swimming velocity (SV) at 87.5, 90, and 92.5% of the maximal aerobic velocity for MLSS velocity (MLSSv) determination. Two square-wave transitions of 500 m, 2.5% above and below the MLSSv were completed to determine VO2 on-kinetics. End-exercise VO2 at 97.5 and 102.5% of MLSSv represented, respectively, 81 and 97% of VO2max; the latter was not significantly different from maximal VO2 (VO2max). The VO2 at MLSSv (49.3 ± 9.2 ml·kg(-1)·min(-1)) was not significantly different from the second ventilatory threshold (VT2) (51.3 ± 7.6 ml·kg(-1)·min(-1)). The velocity associated with MLSS seems to be accurately estimated by the SV at VT2 (vVT2), and vVO2max also seems to be estimated with accuracy from the central 300-m mean velocity of a 400-m trial, indicators that represent a helpful tool for coaches. The 400-m swimming performance (T400) was correlated with the time constant of the primary phase VO2 kinetics (τp) at 97.5% MLSSv, and T800 was correlated with τp in both 97.5 and 102.5% of MLSSv. The assessment of the VO2 kinetics in swimming can help coaches to build training sets according to a swimmer's individual physiological response.


Asunto(s)
Umbral Anaerobio/fisiología , Natación/fisiología , Adolescente , Rendimiento Atlético/fisiología , Prueba de Esfuerzo , Humanos , Cinética , Masculino , Consumo de Oxígeno/fisiología , Distribución Aleatoria , Adulto Joven
16.
Brain Behav Immun ; 39: 186-93, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24412212

RESUMEN

High intensity training regimens appear to put athletes at a higher risk of illness. As these have been linked to alterations in the proportions of differentiated T cells, how training load affects these populations could have important implications for athlete susceptibility to disease. This study examined the effect of a winter training season on the proportions of circulating naïve and memory T cells subsets of high competitive level swimmers. Blood samples were taken at rest at 4 time-points during the season: before the start of the season (t0-September), after 7weeks of an initial period of gradually increasing training load (t1-November), after 6weeks of an intense training cycle (t2-February) and 48h after the main competition (t3-April) and from eleven non-athlete controls at 2 similar time-points (t2 and t3). CD4, CD8 and gamma-delta (γδ) T cells expressing the naïve (CCR7(+)CD45RA(+)), central-memory (CM-CCR7(+)CD45RA(-)), effector-memory (EM-CCR7(-)CD45RA(-)) and terminal effector (TEMRA-CCR7(-)CD45RA(+)) were quantified by flow cytometry. Statistical analyses were performed using multilevel modeling regression. Both T CD4(+) naïve and CM presented a linear increase in response to the first moment of training exposure, and had an exponential decrease until the end of the training exposure. As for TCD4(+) EM, changes were observed from t2 until the end of the training season with an exponential trend, while TCD4(+) TEMRA increased linearly throughout the season. TCD8(+) naïve increased at t1 and decreased exponentially thereafter. TCD8(+) TEMRA values decreased at t1 and increased exponentially until t3. γδT-EM had an increase at t1 and an exponential decrease afterwards. In contrast, γδT-TEMRA decreased at t1 and exponentially increased during the remaining 20weeks of training. An increase in TEMRA and EM T cells alongside a decrease in naïve T cells could leave athletes more susceptible to illness in response to variation in training stimulus during the season.


Asunto(s)
Natación/fisiología , Subgrupos de Linfocitos T/inmunología , Adolescente , Adulto , Atletas , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Femenino , Humanos , Memoria Inmunológica , Masculino , Adulto Joven
17.
J Sports Sci Med ; 13(3): 708-14, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25177203

RESUMEN

Studies examining the immune response to acute intensive swimming have shown increased leukocytosis and lymphocyte populations. However, studies concerning mucosal immunity and sex differences remain controversial. The objective of the study was to examine sex differences on the immune response to maximal incremental swimming exercise in well trained swimmers. Participants (11 females, controlled for menstrual cycle phase effects; 10 males) performed a maximal incremental 7x200 m front crawl set. Fingertip capillary blood samples were obtained after each 200 m swim for lactate assessment. Venous blood and saliva samples were collected before and 5 minutes after the swimming test to determine total numbers of leukocytes, lymphocytes and subpopulations, and serum and salivary immunoglobulin A (IgA) levels. IgA secretion rate was calculated. Menstrual cycle phase did not influence the immune response to exercise. As for sex differences, exercise induced an increase in leukocytes, total lymphocytes, CD3(+), CD4(+), CD8(+), and CD16(+)/56(+) in males. In females, only leukocytosis, of a lower magnitude than was observed in males, occurred. CD19(+) increased and CD4(+)/CD8(+) ratio decreased in both groups following exercise whilst IgA, SIgA concentrations, and srIgA did not change. Both males and females finished the incremental exercise very close to the targeted race velocity, attaining peak blood lactate concentrations of 14.6±2.25 and 10.4±1.99 mmol.L(-1), respectively. The effect of a maximal incremental swimming task on immunity is sex dependent and more noticeable in men. Males, as a consequence of higher levels of immunosurveillance may therefore be at a lower risk of infection than females. Key PointsMaximal exercise induces an immune response.This study investigated the influence of sex over the leukocytes subpopulations and mucosal immune responses to maximal swimming.Male swimmers showed a stronger increase of T helper, T cytotoxic and NK lymphocytes than females, suggesting they may be at a lower risk of infection, due to a higher immunosurveillance.Mucosal immunity remained unchanged in both sexes.

18.
Cells ; 13(13)2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38995013

RESUMEN

Skeletal muscle regeneration after injury is a complex process involving inflammatory signaling and myoblast activation. Pro-inflammatory cytokines like tumor necrosis factor-alpha (TNF-α) are key mediators, but their effects on gene expression in proliferating myoblasts are unclear. We performed the RNA sequencing of TNF-α treated C2C12 myoblasts to elucidate the signaling pathways and gene networks regulated by TNF-α during myoblast proliferation. The TNF-α (10 ng/mL) treatment of C2C12 cells led to 958 differentially expressed genes compared to the controls. Pathway analysis revealed significant regulation of TNF-α signaling, along with the chemokine and IL-17 pathways. Key upregulated genes included cytokines (e.g., IL-6), chemokines (e.g., CCL7), and matrix metalloproteinases (MMPs). TNF-α increased myogenic factor 5 (Myf5) but decreased MyoD protein levels and stimulated the release of MMP-9, MMP-10, and MMP-13. TNF-α also upregulates versican and myostatin mRNA. Overall, our study demonstrates the TNF-α modulation of distinct gene expression patterns and signaling pathways that likely contribute to enhanced myoblast proliferation while suppressing premature differentiation after muscle injury. Elucidating the mechanisms involved in skeletal muscle regeneration can aid in the development of regeneration-enhancing therapeutics.


Asunto(s)
Proliferación Celular , Mioblastos , Transducción de Señal , Factor de Necrosis Tumoral alfa , Mioblastos/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Proliferación Celular/efectos de los fármacos , Animales , Ratones , Línea Celular , Quimiocinas/metabolismo , Quimiocinas/genética , Citocinas/metabolismo , Citocinas/genética , Regulación de la Expresión Génica/efectos de los fármacos
19.
Sci Rep ; 14(1): 20652, 2024 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-39232125

RESUMEN

Long COVID has been linked to a decline in physical activity and functional capacity. However, it remains unclear which physical symptoms are associated with specific aspects of movement behaviors and functional capacity. We aimed to investigate the associations of fatigue, dyspnea, post-exertional malaise, myalgia, and the co-occurrence of symptoms with movement behaviors and functional capacity in individuals with Long COVID. A cross-sectional multicenter study was conducted. Questionnaires were used to assess fatigue, dyspnea, post-exertional malaise, and myalgia. Accelerometry was employed to assess sedentary time, steps per day, light physical activity, and moderate-to-vigorous physical activity. The six-minute walk test, 30-s chair stand test, and timed up and go were used to assess functional capacity. One hundred and two community-dwelling individuals who had been living with Long COVID for 15 ± 10 months participated in the study. Fatigue, post-exertional malaise, and the co-occurrence of physical symptoms showed a negative association with step count, while post-exertional malaise was also negatively associated with moderate-to-vigorous physical activity. Dyspnea showed a negative association with the functional score, including all tests. Our findings suggest that fatigue, post-exertional malaise, and the co-occurrence of physical symptoms are negatively associated with physical activity, while dyspnea is negatively associated with functional capacity in individuals with Long COVID.


Asunto(s)
Acelerometría , COVID-19 , Disnea , Ejercicio Físico , Fatiga , Humanos , Masculino , Femenino , COVID-19/fisiopatología , COVID-19/complicaciones , Estudios Transversales , Persona de Mediana Edad , Fatiga/fisiopatología , Anciano , Disnea/fisiopatología , Síndrome Post Agudo de COVID-19 , SARS-CoV-2/aislamiento & purificación , Movimiento , Encuestas y Cuestionarios , Mialgia/fisiopatología , Adulto
20.
Br J Haematol ; 162(3): 336-47, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23725219

RESUMEN

Although specific microRNA (miRNA) signatures in classical Hodgkin lymphoma (cHL) have been proposed, their relationship with clinical outcome remains unclear. Despite treatment advances, a substantial subset of patients with advanced cHL are refractory to standard therapies based on adriamycin and its variants. Global miRNA expression data of 29 advanced cHL patients and five cHL-derived cell lines were used to identify profiles from Hodgkin-Reed-Sternberg (HRS) cells and their non-tumoural microenvironment. A cHL-miRNA signature was identified with 234 miRNAs differentially expressed. A subset of these miRNAs was associated with outcome and selected for study in an independent set of 168 cHL samples using quantitative reverse transcription polymerase chain reaction. Multivariate Cox regression analyses including cross-validation with failure-free survival (FFS) as clinical endpoint revealed a miRNA signature with MIR21, MIR30E, MIR30D and MIR92B* that identified two risk-groups with significant differences in 5-year FFS (81% vs. 35.7%; P < 0.001). Additionally, functional silencing of MIR21 and MIR30D in L428 cells showed increased sensitivity to doxorubicin-induced apoptosis, pointing towards abnormalities of mitochondrial intrinsic and TP53-CDKN1A pathways as related to miRNA deregulation in cHL. These results suggest that clinical outcome in cHL is associated with a specific miRNA signature. Moreover, functional analyses suggest a role for MIR21 and MIR30D in cHL pathogenesis and therapeutic resistance.


Asunto(s)
Biomarcadores de Tumor/genética , Enfermedad de Hodgkin/genética , MicroARNs/genética , ARN Neoplásico/genética , Adulto , Anciano , Antibióticos Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Apoptosis/efectos de los fármacos , Doxorrubicina/farmacología , Femenino , Perfilación de la Expresión Génica/métodos , Silenciador del Gen , Enfermedad de Hodgkin/tratamiento farmacológico , Enfermedad de Hodgkin/patología , Humanos , Masculino , MicroARNs/metabolismo , Persona de Mediana Edad , Estadificación de Neoplasias , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Células de Reed-Sternberg/metabolismo , Análisis de Supervivencia , Resultado del Tratamiento , Células Tumorales Cultivadas , Microambiente Tumoral , Adulto Joven
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