Diversity and evolution of macrohabitat use, body size and morphology in a monophyletic group of Neotropical pitvipers (Bothrops)

The Neotropical pitviper genus Bothrops comprises about 40 species, which occur in all main ecosystems of cis-Andean South America. We explored the relationships of body size and form (tail length and stoutness) with macrohabitat use in 20 forms of Bothrops. Sen-ii-arboreal habits appeared only in forest forms. Semi-arboreals are significantly more slender and have longer tails than terrestrials; body size is not significantly different between terrestrials and semi-arboreals. Within Bothrops, independent contrasts for macrohabitat use were significantly correlated with contrasts of tail size (positively) and stoutness (negatively); thus, the more arboreal the species, the longer its tail and the more slender its body. Contrasts of adult body size seems to remain constant over the lower range of macrohabitat use, but to decrease in species of Bothrops which are more arboreal. Reconstructions of character states indicate that: (1) the ancestor of Bothrops was a small, stout, terrestrial species; (2) semi-arboreal habits appeared one to three times in the genus; (3) a decrease in stoutness and an increase in tail length occurred along with an increase in arboreality in some clades. Although macrohabitat use seems to be important in determining body form in Bothrops, our results also indicate that tail size, stoutness and body size may also be affected by selective agents other than macrohabitat use. The selective agents responsible for the shifts in macrohabitat use in Bothrops are still uncertain, although they may have included prey availability and/or predation pressure. The plasticity of macrohabitat use, morphology and body size described in this study may have been key features that facilitated the highly successful ecological diversification of Bothrops in South America.

Atomic Bose-Einstein condensation with three-body interactions and collective excitations

The stability of a Bose-Einstein condensed state of trapped ultra-cold atoms is investigated under the assumption of an attractive two-body and a repulsive three-body interaction. The Ginzburg-Pitaevskii-Gross (GPG) nonlinear Schrodinger equation is extended to include an effective potential dependent on the square of the density and solved numerically for the s-wave. The lowest collective mode excitations are determined and their dependences on the number of atoms and on the strength of the three-body force are studied. The addition of three-body dynamics can allow the number of condensed atoms to increase considerably, even when the strength of the three-body force is very small compared with the strength of the two-body force. We study in detail the first-order liquid-gas phase transition for the condensed state, which can happen in a critical range of the effective three-body force parameter.

Virtual States, Halos and Resonances in Three-Body Atomic and Nuclear Systems

By considering nuclear and ultracold trapped atomic systems, we review the trajectory of Efimov excited states in the complex plane by changing the two-body scattering lengths and one three-body scale.

Body size and flight distance in stingless bees (Hymenoptera: Meliponini): inference of flight range and possible ecological implications

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A Hypercaloric pellet-diet cycle induces obesity and co-morbidities in wistar rats

O objetivo do estudo foi desenvolver um ciclo de dietas hipercalóricas para promover obesidade em ratos. Ratos Wistar foram distribuídos em dois grupos: dieta normal (ND = 32; 3,5 kcal/g) e dietas hipercalóricas (HD; n = 32; 4,6 kcal/g). O grupo ND recebeu ração comercial e os animais HD um ciclo de diferentes dietas hipercalóricas, por 14 semanas. As variáveis analisadas foram peso corporal, parâmetros metabólicos e hormonais, pressão arterial sistólica e teste oral de tolerância à glicose. O nível de significância foi de 5%. O ciclo de dietas hipercalóricas promoveu aumento de peso e gordura corporal, pressão arterial sistólica e níveis séricos de glicose, triacilglicerol, insulina e leptina no grupo HD. Além disso, o grupo HD apresentou tolerância à glicose diminuída. em conclusão, os resultados deste estudo mostram que o ciclo de dietas hipercalóricas promove obesidade e exibe várias características comumente associadas com a obesidade humana, como aumento da pressão arterial, resistência à insulina, hiperglicemia, hiperinsulinemia, hiperleptinemia e dislipidemia.

Modulation of parasitemia and antibody responce to Trypanosoma cruzy by cyclophosphamide in Calomys callosus (Rodentia, Cricetidae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effects of prolonged oral administration of fumonisin B(1) and aflatoxin B(1) in rats

The effects of prolonged oral administration (21 days) of fumonisin B(1) (FB(1)) and aflatoxin B(1) (AFB(1)) were evaluated on male Wistar rats. The animals were housed in individual metabolic cages and submitted to the following treatments: 1-0 mug AFB(1) + 0 mg FB(1)/100g bw.; 2-72 mug AFB(1)+ 0 mg FB(1)/100 g bw; 3-0 mug AFB(1) + 0.5 mg FB(1) g bw; 4-0 mug AFB(1) + 1.5 mg FB(1)/100 g bw; 5-72 mug AFB(1) + 0.5 mg FB(1)/100g bw; 6-72 mu gAFB(1) + 1.5 mg FB(1)/100g bw. on day 21, the rats were sacrificed for evaluation. The results showed that treated animals presented differences in body weight and absolute/relative weights of liver and kidney as well as altered hepatic function and cholesterol blood levels. Rats fed with the greatest doses of AFB(1) and FB(1) gained less weight (2.79 g/day) at the end of the experimental period; their blood concentrations of liver enzymes aspartate aminotransferase (AST) and alkaline phosphatase (AP) were above control levels (130.35 mu /l and 471.00 mu /l, respectively). Blood cholesterol increased in the groups treated with the highest dose of FB(1) or FB(1) associated with AFB(1). Histopathology revealed the occurrence of apoptosis in the liver of rats exposed to FB(1). The association of aflatoxin B(1) with fumonisin B(1) at higher dose probably potentiated the effects of the higher dose of fumonisin B(1)acting singly.

Ventricular remodeling and diastolic myocardial dysfunction in rats submitted to protein-calorie malnutrition

The effects of protein-calorie malnutrition (PCM) on heart structure and function are not completely understood. We studied heart morphometric, functional, and biochemical characteristics in undernourished young Wistar rats. They were submitted to PCM from birth (undernourished group, UG). After 10 wk, left ventricle function was studied using a Langendorff preparation. The results were compared with age-matched rats fed ad libitum (control group, CG). The UG rats achieved 47% of the body weight and 44% of the left ventricular weight (LVW) of the CG. LVW-to-ventricular volume ratio was smaller and myocardial hydroxyproline concentration was higher in the UG. Left ventricular systolic function was not affected by the PCM protocol. The myocardial stiffness constant was greater in the UG, whereas the end-diastolic pressure-volume relationship was not altered. In conclusion, the heart is not spared from the adverse effects of PCM. There is a geometric alteration in the left ventricle with preserved ventricular compliance despite the increased passive myocardial stiffness. The systolic function is preserved.

MODULATION OF PARASITEMIA AND ANTIBODY-RESPONSE TO TRYPANOSOMA-CRUZI BY CYCLOPHOSPHAMIDE IN CALOMYS-CALLOSUS (RODENTIA, CRICETIDAE)

Calomys callosus a wild rodent, previously described as harboring Trypanosoma cruzi, has a low susceptibility to infection by this protozoan.Experiments were designed to evaluate the contribution of the immune response to the resistance to T. cruzi infection exhibited by C. callosus. Animals were submitted to injections of high (200 mg/kg body weight) and low (20 mg/kg body weight) doses of cyclophosphamide on days -1 or -1 and +5, and inoculated with 4 x 10(3) T. cruzi on day O. Parasitemia, mortality and antibody response as measured by direct agglutination of trypomastigotes were observed. Two hundred mg doses of cyclophosphamide resulted in higher parasitemia and mortality as well as in suppression of the antibody response. A single dose of 20 mg enhanced antibody levels on the 20th day after infection, while an additional dose did not further increase antibody production. Parasitemia levels were not depressed, but rather increased in both these groups as compared to untreated controls. Passive transfer of hyperimmune C. callosus anti-T. cruzi serum to cyclophosphamide immunosuppressed animals resulted in lower parasitemia and mortality rates. These results indicate that the immune response plays an important role in the resistance of C. callosus to T. cruzi.

Effects of 2 or 5 consecutive exercise days on adipocyte area and lipid parameters in Wistar rats

Background: Exercise has been prescribed in the treatment and control of dyslipidemias and cholesterolemia, however, lipid responses to different training frequencies in hypercholesterolemic men have been inconsistent. We sought to verify if different frequencies of continuous moderate exercise (2 or 5 days/week, swimming) can, after 8 weeks, promote adaptations in adipocyte area and lipid parameters, as well as body weight and relative weight of tissues in normo and hypercholesterolemic adult male rats.Methods: Normal cholesterol chow diet or cholesterol-rich diet (1% cholesterol plus 0.25% cholic acid) were freely given during 8 weeks to the rats divided in 6 experimentals groups: sedentary normal cholesterol chow diet (C); sedentary cholesterol-rich diet (H); 5x per week continuous training normal cholesterol chow diet (TC5) and cholesterol-rich diet (TH5); 2x per week continuos traning normal cholesterol chow diet (TC2) and cholesterol-rich diet (TH2).Results: No changes were observed in lipid profile in normal cholesterol chow diet, but both 2 a 5 days/week exercise improved this profile in cholesterol-rich diet. Body weight gain was lower in exercised rats. Decrease in retroperitoneal and epididymal relative weights as well as reductions in adipocyte areas under all diets types were observed only in 5 days/week, while 2 days/week showed improvements mainly in cholesterol-rich diet rats.Conclusion: Our results confirm the importance of exercise protocols to control dyslipidemias and obesity in rats. The effects of 5 days/week exercise were more pronounced compared with those of 2 consecutive days/week training.

Effects of soy protein and resistance exercise on body composition and blood lipids in postmenopausal women

Objective: To assess the effect of soy protein and progressive resistance training on body composition and lipids in postmenopausal women.Design: In a controlled trial, 46 postmenopausal women were randomized to one of four groups: 25 g of soy protein (SP, n = 10), 25 g of soy protein plus resistance exercise (SPE, n = 14), 25 g of maltodextrine (placebo) (PL, n = 11), or placebo plus resistance exercise (PLE, n = 11). Progressive resistance training was held three times a week for 16 weeks and included 8 exercises (3 series of 8-12 repetitions). At baseline and after 16 weeks, body mass index, waist circumference (WC), body fat, muscle mass and serum lipid levels were measured. To confirm isoflavone absorption, urinary concentrations were determined. The t-test of Student and ANOVA were used in the statistical analysis.Results: Subjects were classified as overweight and showed android fat distribution: Urinary isoflavone excretion indicated compliance to soy protein treatment. After 16 weeks of intervention, both SPE and PLE groups showed a significant increase of 1.3 kg in muscle mass and reduction in WC of -1.4 and -2.1 cm, respectively (p < 0.05). Significant decreases in the mean values of total cholesterol and LDL (-29.0 and -24.0 mg/dL, p < 0.001 and p < 0.006, respectively) were observed in the users of soy protein alone (SP).Conclusions: Soy protein supplementation did not influence the indicators of body composition. However, it exerted possible favorable effects on lipid profile in postmenopausal women. The increase in muscle mass and reduction in abdominal fat were correlated with resistance training. (c) 2006 Elsevier B.V.. All rights reserved.

Demonstration of the cellular viability and safety of Enterococcus faecium CRL 183 in long-term experiments

Enterococcus faecium CRL 183, a strain isolated from NSLAB cheese starter, has been the focus of much research on its potential probiotic capacity, although its survival through the gastrointestinal tract has not been demonstrated so far. In order to determine the capacity of E. faecium CRL 183 to survive such conditions, this strain was administered daily to rats for 30 weeks. The experimental animals were divided into Group I: those that did not receive E. faecium, Group II: those that received a pure culture of E. faecium CRL 183 and Group III: animals that received E. faecium CRL 183 in the form of a fermented soy-based product. Faecal samples were collected at the beginning and at the 50%, 75% and 100% stages of the experimental period. Isolation and counts of Enterococcus were carried out on KF selective media. To distinguish the various Enterococcus species in the faeces, biochemical (API Strep 20) and molecular (PCR) tests were performed. Initially, E. faecium was absent from the intestinal flora of the rats; however, after 15 weeks of administration, E. faecium could be recovered from the faeces of Groups II and III, demonstrating that E. faecium CRL 183 was able to survive gastrointestinal transit under the study conditions. This is further evidence of the probiotic qualities of this strain. The safety of the strain was also investigated with regard to body weight and serum biochemical analysis.