426 research outputs found

    Transference of natural diversity from the apomictic germplasm of Paspalum notatum to a sexual synthetic population

    Get PDF
    Genetic improvement in apomictic forage species has been restricted because of the absence of genetic variability in sexual germplasm with the same ploidy level. Following a new breeding scheme, a sexual synthetic tetraploid population (SSTP) of Paspalum notatum has been generated. The objectives of this work were: (a) to evaluate the genetic variability in SSTP by means of molecular markers, morphologic and agronomic traits, and seed fertility and quality traits and (b) to assess the transference of genetic variability from the apomictic germplasm to the sexual one. Molecular markers revealed a twofold higher level of variability in the SSTP in comparison with the sexual germplasm utilised for its generation, and similar levels with the apomictic ones; moreover, markers showed that most of the variability was inherited from theapomictic germplasm. Morphologic and agronomic traits and seed fertility and quality traits showed high levels of variation in the three groups of genotypes indicating that the new breeding scheme was effective in transferring variability from the apomictic germplasm to the SSTP. This new population will be useful in breeding of P. notatum, and the breeding scheme used for its generation may be used in other apomictic species.Fil: Zilli, Alex Leonel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Acuña, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Schulz, Roberto R.. Universidad Nacional del Nordeste; ArgentinaFil: Marcón, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Brugnoli, Elsa Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Novo, Sabina F.. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias; ArgentinaFil: Quarin, Camilo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Martínez, Eric Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentin

    Aerobic capacity, activity levels and daily energy expenditure in male and female adolescents of the kenyan nandi sub-group

    Get PDF
    The relative importance of genetic and socio-cultural influences contributing to the success of east Africans in endurance athletics remains unknown in part because the pre-training phenotype of this population remains incompletely assessed. Here cardiopulmonary fitness, physical activity levels, distance travelled to school and daily energy expenditure in 15 habitually active male (13.9±1.6 years) and 15 habitually active female (13.9±1.2) adolescents from a rural Nandi primary school are assessed. Aerobic capacity ([Formula: see text]) was evaluated during two maximal discontinuous incremental exercise tests; physical activity using accelerometry combined with a global positioning system; and energy expenditure using the doubly labelled water method. The [Formula: see text] of the male and female adolescents were 73.9±5.7 ml(.) kg(-1.) min(-1) and 61.5±6.3 ml(.) kg(-1.) min(-1), respectively. Total time spent in sedentary, light, moderate and vigorous physical activities per day was 406±63 min (50% of total monitored time), 244±56 min (30%), 75±18 min (9%) and 82±30 min (10%). Average total daily distance travelled to and from school was 7.5±3.0 km (0.8-13.4 km). Mean daily energy expenditure, activity-induced energy expenditure and physical activity level was 12.2±3.4 MJ(.) day(-1), 5.4±3.0 MJ(.) day(-1) and 2.2±0.6. 70.6% of the variation in [Formula: see text] was explained by sex (partial R(2) = 54.7%) and body mass index (partial R(2) = 15.9%). Energy expenditure and physical activity variables did not predict variation in [Formula: see text] once sex had been accounted for. The highly active and energy-demanding lifestyle of rural Kenyan adolescents may account for their exceptional aerobic fitness and collectively prime them for later training and athletic success

    Contribution of abdominal adiposity to age-related differences in insulin sensitivity and plasma lipids in healthy nonobese women

    Get PDF
    WSTĘP. Autorzy sprawdzili słuszność hipotezy zakładającej, że związany z wiekiem przyrost tkanki tłuszczowej trzewnej odpowiada częściowo za ujemny wpływ na insulinowrażliwość i profil lipidowy u kobiet bez otyłości. MATERIAŁ I METODY. Bezpośrednio oceniono: powierzchnię podskórnej i trzewnej tkanki tłuszczowej (tomografia komputerowa), zużycie glukozy (badanie metodą hiperinsulinowej/euglikemicznej klamry metabolicznej), elementy składowe organizmu (metoda absorpcjometrii promieniami X dwoistej energii), profil lipidowy oraz maksymalne zużycie tlenu (VO2max) u 178 kobiet bez otyłości, zakwalifikowanych do odpowiednich grup wiekowych: grupa 1 - 28 &plusmn; 4 lata (n = 88); grupa 2 - 46 &plusmn; 2 lata (n = 38); grupa 3 - 53 &plusmn; 2 lata (n = 31); grupa 4 - 67 &plusmn; 6 lat (n = 21). WYNIKI. Powierzchnia trzewnej tkanki tłuszczowej zwiększa się wraz z wiekiem (2,36 cm2 rocznie, p < 0,0001). Zanotowano związany z wiekiem wzrost stężenia cholesterolu całkowitego (p < 0,0003), triglicerydów (p < 0,0009), cholesterolu frakcji LDL (p < 0,027) i stosunku stężenia cholesterolu całkowitego do cholesterolu frakcji HDL (p < 0,042). Obserwowane różnice w insulinowrażliwości także wiązały się z wiekiem, jednakże w tym przypadku zależność była odmienna. Insulinowrażliwość, wyrażona jako całkowita lub przeliczona na kilogram beztłuszczowej masy ciała, była najniższa w grupie 4, ale nie różniła się istotnie między grupami 1, 2 i 3. Po analizie statystycznej, uwzględniającej powierzchnię tkanki tłuszczowej trzewnej, niższa insulinowrażliwość utrzymywała się, jednocześnie, relatywnie zmniejszyła się różnica w porównaniu z pozostałymi grupami. Wpływ zawartości trzewnej tkanki tłuszczowej na związane z wiekiem zmiany profilu lipidowego był silniejszy. Różnice w powierzchni trzewnej i głębokiej podskórnej tkanki tłuszczowej znosiły wpływ wieku na stężenie cholesterolu całkowitego, triglicerydów i cholesterolu frakcji LDL. Nie obserwowano natomiast wpływu wartości VO2max lub aktywnego wypoczynku na zależne od wieku zmiany w insulinowrażliwości bądź profilu lipidowym. WNIOSKI. 1) Wraz z wiekiem zwiększa się powierzchnia trzewnej tkanki tłuszczowej, podczas gdy zmniejszenie insulinowrażliwości obserwuje się tylko u kobiet starszych; 2) Związane z wiekiem różnice w trzewnej tkance tłuszczowej tylko w niewielkim stopniu odpowiadają za spadek insulinowrażliwości u kobiet bez otyłości; 3) Niepożądane zmiany profilu lipidowego w dużym stopniu wiążą się z zależnym od wieku przyrostem trzewnej tkanki tłuszczowej.INTRODUCTION. We examined the hypothesis that an age-related increase in the compartments of visceral fat would account, in part, for the deleterious changes in insulin sensitivity and blood lipid profile in nonobese women. MATERIAL AND METHODS. We directly assessed visceral and subcutaneous abdominal adipose tissue areas (computed tomography), glucose disposal (hyperinsulinemic-euglycemic clamp), body composition (dual energy X-ray absorptiometry), blood-lipid profile, and aerobic fitness (VO2max) in 178 nonobese women categorized into four age groups: group 1, 28 &plusmn; 4 years, n = 88; group 2, 46 &plusmn; 2 years, n = 38; group 3, 53 &plusmn; 2 years, n = 31; and group 4, 67 &plusmn; 6 years, n = 21. RESULTS. Visceral abdominal adipose tissue area increased with age (2.36 cm2 per year, P < 0.0001). We noted an age-related increase in total cholesterol (P < 0.0003), triglycerides (P < 0.0009), LDL cholesterol (P < 0.027), and the ratio of total cholesterol to HDL cholesterol (P < 0.042). However, agerelated changes in insulin sensitivity exhibited a different age-related pattern. That is, insulin sensitivity, expressed on an absolute basis or indexed per kilogram of fat-free mass, was lowest in group 4 but was not significantly different among groups 1, 2, and 3. After statistical control for visceral fat, lower insulin sensitivity persisted in group 4, although differences were diminished relative to other groups. However, the effect of visceral fat on agerelated changes in the blood-lipid profile was stronger. That is, differences in visceral and deep subcutaneous adipose tissue area abolished age-related differences in total cholesterol, triglycerides, and LDL cholesterol. No independent effects of VO2max or leisure-time physical activity on age-related changes in insulin sensitivity or on the blood-lipid profile were noted. CONCLUSIONS. We conclude that 1) visceral fat shows an increase with advancing age, whereas a decrease in insulin sensitivity was noted only in older women; 2) age-related differences in visceral fat explain only a modest part of the decline in insulin sensitivity in nonobese women; and 3) unfavorable changes in plasma lipids were strongly associated with the age-related increase in visceral abdominal adipose tissue

    Loneliness, social support and cardiovascular reactivity to laboratory stress

    No full text
    Self-reported or explicit loneliness and social support have been inconsistently associated with cardiovascular reactivity (CVR) to stress. The present study aimed to adapt an implicit measure of loneliness, and use it alongside the measures of explicit loneliness and social support, to investigate their correlations with CVR to laboratory stress. Twenty-five female volunteers aged between 18 and 39 years completed self-reported measures of loneliness and social support, and an Implicit Association Test (IAT) of loneliness. The systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) reactivity indices were measured in response to psychosocial stress induced in the laboratory. Functional support indices of social support were significantly correlated with CVR reactivity to stress. Interestingly, implicit, but not explicit, loneliness was significantly correlated with DBP reactivity after one of the stressors. No associations were found between structural support and CVR indices. Results are discussed in terms of validity of implicit versus explicit measures and possible factors that affect physiological outcomes

    Normal Values of Circulating IGF-I Bioactivity in the Healthy Population: Comparison with five widely used IGF-I immunoassays

    Get PDF
    Background: IGF-I immunoassays are primarily used to estimate IGF-I bioactivity. Recently, an IGFI specific Kinase Receptor Activation Assay (KIRA) has been developed as an alternative method. However, no normative values have been established for the IGF-I KIRA. Objective: To establish normative values for the IGF-I KIRA in healthy adults. Design: Cross-sectional study in healthy non-fasting blood donors. Study participants: 426 healthy individuals (310 M, 116 F; age range: 18 – 79 yrs) Main outcome Measures: IGF-I bioactivity determined by the KIRA. Results were compared with total IGF-I, measured by five different IGF-I immunoassays. Results: Mean (± SD) IGF-I bioactivity was 423 (± 131) pmol/L and decreased with age (β = -3.4 pmol/L/yr, p < 0.001). In subjects younger than 55 yrs mean IGF-I bioactivity was significantly higher in women than in men. Above this age this relationship was inverse, suggesting a drop in IGF-I bioactivity after menopause. This drop was not reflected in total IGF-I levels. IGF-I bioactivity was significantly related to total IGF-I (rs varied between 0.46 – 0.52; P-values < 0.001). Conclusions: We established age-specific normative values for the IGF-I KIRA. We observed a significant drop in IGF-I bioactivity in women between 50 and 60 years, which was not perceived by IGF-I immunoassays. The IGF-I KIRA, when compared to IGF-I immunoassays, theoretically has the advantage that it measures net effects of IGF-binding proteins on IGF-I receptor activation. However, it has to be proven whether information obtained by the IGF-I KIRA is clinically more relevant than measurements obtained by IGF-I immunoassays

    Resistance training with soy vs whey protein supplements in hyperlipidemic males

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Most individuals at risk for developing cardiovascular disease (CVD) can reduce risk factors through diet and exercise before resorting to drug treatment. The effect of a combination of resistance training with vegetable-based (soy) versus animal-based (whey) protein supplementation on CVD risk reduction has received little study. The study's purpose was to examine the effects of 12 weeks of resistance exercise training with soy versus whey protein supplementation on strength gains, body composition and serum lipid changes in overweight, hyperlipidemic men.</p> <p>Methods</p> <p>Twenty-eight overweight, male subjects (BMI 25–30) with serum cholesterol >200 mg/dl were randomly divided into 3 groups (placebo (n = 9), and soy (n = 9) or whey (n = 10) supplementation) and participated in supervised resistance training for 12 weeks. Supplements were provided in a double blind fashion.</p> <p>Results</p> <p>All 3 groups had significant gains in strength, averaging 47% in all major muscle groups and significant increases in fat free mass (2.6%), with no difference among groups. Percent body fat and waist-to-hip ratio decreased significantly in all 3 groups an average of 8% and 2%, respectively, with no difference among groups. Total serum cholesterol decreased significantly, again with no difference among groups.</p> <p>Conclusion</p> <p>Participation in a 12 week resistance exercise training program significantly increased strength and improved both body composition and serum cholesterol in overweight, hypercholesterolemic men with no added benefit from protein supplementation.</p
    corecore