Experimental evolution for generalists and specialists reveals multivariate genetic constraints on thermal reaction norms

Theory predicts the emergence of generalists in variable environments and antagonistic pleiotropy to favour specialists in constant environments, but empirical data seldom support such generalist–specialist trade-offs. We selected for generalists and specialists in the dung fly Sepsis punctum (Diptera: Sepsidae) under conditions that we predicted would reveal antagonistic pleiotropy and multivariate trade-offs underlying thermal reaction norms for juvenile development. We performed replicated laboratory evolution using four treatments: adaptation at a hot (31 °C) or a cold (15 °C) temperature, or under regimes fluctuating between these temperatures, either within or between generations. After 20 generations, we assessed parental effects and genetic responses of thermal reaction norms for three correlated life-history traits: size at maturity, juvenile growth rate and juvenile survival. We find evidence for antagonistic pleiotropy for performance at hot and cold temperatures, and a temperature-mediated trade-off between juvenile survival and size at maturity, suggesting that trade-offs associated with environmental tolerance can arise via intensified evolutionary compromises between genetically correlated traits. However, despite this antagonistic pleiotropy, we found no support for the evolution of increased thermal tolerance breadth at the expense of reduced maximal performance, suggesting low genetic variance in the generalist–specialist dimension.

Reproductive migration and population dynamics of the blue crab Callinectes danae in an estuary in southeastern Brazil

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

Habitat use and home range of brown-nosed coati, Nasua nasua (Carnivora: Procyonidae) in the Brazilian Cerrado biome

The brown-nosed coati (Nasua nasua) is a carnivorous species found in all the Brazilian biomes, some of which are endangered areas. The aim of this work was to determine the habitat use and selection, home range and core area of N. nasua in the Cerrado biome, central region of Tocantins, Brazil. The study was carried out in an area of approximately 20 000ha from May 2000 to July 2002. A total of seven box traps were placed in the area for 13 months, three of 11 captured animals were followed and monitored by radio-tracking during 13 months. The monitoring was conducted once a day, three times a week using a car and walking through the study area (radio-tracking and visual contact). The results demonstrate that these three males used more frequently the gallery forest formation, followed by cerrado and wetlands. The use of gallery forest by these animals indicated an habitat selection (Proportion test, z=12.98, p< 0.01). Besides, adult males used the gallery forest more frequently (Fisher's exact test, p<0.01) and wetlands less frequently (Fisher's exact test, p<0.01) than juvenile males, without significant differences between animal ages for cerrado percentage of habitat use. Besides, results also showed a gallery forest selection by adult (Proportion test z= 13.62, p<0.01) and juvenile (Proportion test z=2.68, p<0.01) males, and a wetland selection by the juvenile male (Proportion test z=3.90, p<0.01). The home ranges varied from 2.20 to 7.55km2 for the Minimum Convex Polygon 100% (MCP 100%) and from 4.38 to 13.32km2 for the Harmonic Mean 95% (HM 95%). The smallest home range overlap occurred between the adult males (Nm1 and Nm3), and the greatest between the juvenile Njm2 and the adult Nm1. The average of the core area (HM 75%) for the three monitored animals represented 21.29% of the home range calculated with HM 95%. No overlap between core areas was observed for adult males, but, it was an overlap between the core area of the juvenile male and its band with that of the two adult males. The present study provides new data on core area size and frequency habitat use by adult and juvenile males of N. nasua in the Brazilian Cerrado, that may support conservation efforts. Rev. Biol. Trop. 58 (3): 1069-1077. Epub 2010 September 01.

Cytogenetic studies of Brazilian pediatric myelodysplastic syndrome cases: challenges and difficulties in a large and emerging country

Myelodysplastic syndromes (MDS) and juvenile myelomonocytic leukemia (JMML) are rare hematopoietic stem cell diseases affecting children. Cytogenetics plays an important role in the diagnosis of these diseases. We report here the experience of the Cytogenetic Subcommittee of the Brazilian Cooperative Group on Pediatric Myelodysplastic Syndromes (BCG-MDS-PED). We analyzed 168 cytogenetic studies performed in 23 different cytogenetic centers; 84 of these studies were performed in patients with confirmed MDS (primary MDS, secondary MDS, JMML, and acute myeloid leukemia/MDS+Down syndrome). Clonal abnormalities were found in 36.9% of the MDS cases and cytogenetic studies were important for the detection of constitutional diseases and for differential diagnosis with other myeloid neoplasms. These data show the importance of the Cooperative Group for continuing education in order to avoid a late or wrong diagnosis.

Intraspecific Variation of Biological Activities in Venoms from Wild and Captive Bothrops jararaca

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

EFFECTS of DIURON on MALE RAT REPRODUCTIVE ORGANS: A DEVELOPMENTAL and POSTNATAL STUDY

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

Population structure and reproductive period of whitebelly prawn Nematopalaemon schmitti (Holthuis 1950) (Decapoda: Caridea: Palaemonidae) on the southeastern coast of Brazil

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

Developmental changes in cold tolerance and ability to autoresuscitate from hypothermic respiratory arrest are not linked in rats and hamsters

In adult mammals, severe hypothermia leads to respiratory and cardiac arrest, followed by death. Neonatal rats and hamsters can survive much lower body temperatures and, upon artificial rewarming, spontaneously recover from respiratory arrest (autoresuscitate), typically suffering no long-term effects. To determine developmental and species differences in cold tolerance (defined here as the temperature of respiratory arrest) and its relation to the ability to autoresuscitate, we cooled neonatal and juvenile Sprague-Dawley rats and Syrian hamsters until respiration ceased, followed by rewarming. Ventilation and heartbeat were continuously monitored. In rats, cold tolerance did not change throughout development, however the ability to autoresuscitate from hypothermic respiratory arrest did (lost between postnatal days, P, 14 and 20), suggesting that the mechanisms for maintaining breathing at low temperatures was retained throughout development while those initiating breathing on rewarming were altered. Hamsters, however, showed increased cold tolerance until P26-28 and were able to autoresuscitate into adulthood (provided the heart kept beating throughout respiratory arrest). Also, hamsters were more cold tolerant than rats. We saw no evidence of gasping to initiate breathing following respiratory arrest, contributing to the hypothesis that hypothermic respiratory arrest does not lead to anoxia. (C) 2012 Elsevier B.V. All rights reserved.

Neoproterozoic tectonic and magmatic episodes in the NW sector of Borborema Province, NE Brazil, during assembly of Western Gondwana

The Medio Coreau domain of NE Brazil is located along the northwest margin of Borborema Province, the western branch of a Brasiliano/Pan-African collisional belt that formed during the assembly of Western Gondwana. The early Paleoproterozoic basement of the Medio Coreau domain is composed of migmatitic gneisses and juvenile granulites, overlain by late Paleoproterozoic and Neoproterozoic rocks intruded by syn- to post-tectonic Brasiliano granitoids. According to integrated structural and geochronological data (U-Pb zircon and monazite ages), the Neoproterozoic tectonic evolution of the Medio Coreau is characterized by low-angle thrusting and transcurrent deformation. U-Pb geochronological data from plutons intruded during this compressional regime indicate the collisional evolution began at approximately 622 Ma and continued until about 591 Ma. The continuation of convergence until approximately 560 Ma resulted in the formation of NE-SW and E-W shear zones within the Borborema Province and adjoining West African provinces. The final stage of the ductile tectonism was characterized by uplift and high-angle fault generation between approximately 560 and 545 Ma. The last tectonic event was an extensional phase, resulting in the formation of the Jaibaras graben and intrusion of post-orogenic granites at around 532 Ma. (c) 2007 Elsevier Ltd. All rights reserved.

Relationship of venom ontogeny and diet in Bothrops

We studied ontogenetic changes in venom toxicity of the pitvipers Bothrops jararaca and B. alternatus in order to evaluate the relationship between venom action and diet. Toxicity tests (LD50) were performed for the venoms of adult and juvenile snakes on mice and bullfrog froglets, which represented endothermic and ectothermic prey respectively. The venom of juveniles of B. jararaca, but not of B. alternatus, had a higher toxicity on anurans than that of adults. This finding is consistent with the feeding habits of these two species, because juveniles of B. jararaca feed mainly on small anurans and lizards, shifting to endothermic prey at maturity, whereas B. alternatus preys mainly on endotherms throughout its life. Venom toxicity in endotherms was higher for adults of B. jararaca compared to juveniles, a feature not observed for B. alternatus. It is proposed that prey death/immobilization is the main function of the venom of juvenile snakes. As the snake grows, the digestive role of venom may become increasingly important, because adults prey upon large and bulky prey. The importance of adult venoms in prey digestion is reflected in their higher proteolytic activity.

Developmental morphology of mouthparts and foregut of the larvae and postlarvae of Lepidophthalmus siriboia Felder & Rodrigues, 1993 (Decapoda: Callianassidae)

A morfologia dos apêndices bucais e o estômago de larvas e pós-larvas de Lepidophthalmus siriboia cultivados em laboratório foi investigada. Os apêndices bucais (maxilas e maxilípedes) durante os estágios zoeae apresentam número reduzido de cerdas e espinhos, ou mesmo, ausentes em alguns indivíduos. O estômago aparece pouco desenvolvido, com poucas cerdas pequenas nas câmaras cardíaca e pilórica. Contrariamente, após a metamorfose para o estágio megalopa, todas estas estruturas bucais possuem muitas cerdas, e o estômago apresenta um moinho gástrico bem desenvolvido com dois fortes dentes laterais. No estágio juvenil ocorre incremento de cerdas e espinhos em todas estruturas bucais e o estômago torna-se mais especializado. Estas observações sugerem fortemente que as zoeae de L. siriboia têm desenvolvimento lecitotrófico, mas que as megalopae e juvenis passam a ingerir alimentos exógenos.

Development and functional morphology of the foreguts of larvae and postlarvae of three crustacean decapods

O desenvolvimento da estrutura do estômago e da função digestiva foi examinada em larvas e pós-larvas de Litopenaeus vannamei, Sesarma rectum e Callichirus major. O estômago do protozoea de L. vannamei é muito simples, sem válvula cárdiopilórica e apresenta um filtro pilórico rudimentar. Em mysis, o filtro pilórico parece ser mais desenvolvido. No juvenil I surgem calhas e dentes laterais pouco desenvolvidos. Os estômagos dos zoeae de S. rectum possuem a válvula cárdiopilórica e o filtro pilórico funcionais. Nos estágios megalopa e juvenil I o moinho gástrico é complexo. Em C. major, os estômagos dos zoeae se mostram especializados exibindo algumas estruturas rígidas, mas não apresentam moinho gástrico. Esta estrutura surge no megalopa e juvenil I. Os resultados suportam suposições anteriores que o comportamento alimentar de larvas e pós-larvas está diretamente relacionado com as características morfológicas dos estômagos.

Nematode parasites of Pescada Gó, Macrodon ancylodon Bloch and Schneider, 1801 (Osteichthyes, Sciaenidae), from Vila dos Pescadores, Bragança-PA, Brazil

The objective of this work was to evaluate the host/parasite relationship of nematodes in Macrodon ancylodon. Ninety seven fishes (50 in wet season and 47 in dry season) were weighed (167.1 ± 109.9g) and measured (28.3 ± 5.2cm). Only twelve specimens were not infected by any parasites and the prevalence of infection was 87.6%. The highest prevalence values were observed in August and September (dry season, 100%). The stomach was the most infected organ during the whole months (prevalence of 64.2%, and mean intensity of 4.6±7.8 parasites/fish), and the medium intestine showed the lowest infection (prevalence 27.3% and mean intensity 2.5±2.1 parasites/fish). The nematodes were identified as Raphidascaris sp., Goezia sp. and Cucullanus sp. Only the male and juvenile fishes could be presented different values of infection according to rainfall, being more infected in August to October. The female hosts presented higher values of abundance and mean intensity of infection (p<0.01) throughout the year.

Comparação entre o Disease Activity Score-28 e o Juvenile Arthritis Disease Activity Score na artrite idiopática juvenil

Introduction: the assessment of the activity of rheumatoid arthritis and juvenile idiopathic arthritis is made by means of different tools, respectively DAS-28 and JADAS.Objective: To compare DAS-28 and JADAS with scores of 71, 27 and 10 joint counts in juvenile idiopathic arthritis.Method: A secondary analysis of a phase III placebo-controlled trial, testing safety and efficacy of abatacept was conducted in 8 patients with 178 assessment visits. Joint count scores for active and limited joints, physician's and parents'global assessment by 0-10 cm Visual Analog Scale, and erythrocyte sedimentation rate normalized to 0-10 scale, in all visits. The comparison among the activity indices in different observations was made through Anova or adjusted gamma model. The paired observations between DAS-28 and JADAS 71, 27 and 10, respectively, were analyzed by linear regression.Results: There were significant differences among individual measures, except for ESR, in the first four months of biological treatment, when five of the eight patients reached ACR-Pedi 30, with improvement. The indices of DAS-28, JADAS 71, 27 and 10 also showed significant difference during follow-up. Linear regression adjusted model between DAS-28 and JADAS resulted in mathematical formulas for conversion: [DAS-28 = 0.0709 (JADAS 71) + 1.267] (R-2 = 0.49); [DAS-28 = 0.084 (JADAS 27) + 1.7404] (R-2 = 0.47) and [DAS-28 = 0.1129 (JADAS-10) + 1.5748] (R-2 = 0.50).Conclusion: The conversion of scores of DAS-28 and JADAS 71, 27 and 10 for this mathematical model would allow equivalent application of both in adolescents with arthritis. (C) 2014 Elsevier Editora Ltda. All rights reserved.

Impacts of Plant Size, Density, Herbivory, and Desease on Native Platte Thistle (Cirsium Canescens)

Abstract. Based on prior field observations, we hypothesized that individual and interacting effects of plant size, density, insect herbivory, and especially fungal disease, influenced seedling and juvenile plant growth in native Platte thistle populations (Cirsium canescens Nutt.). We worked at Arapaho Prairie in the Nebraska Sandhills (May - August 2007), monitoring plant growth, insect damage, and fungal infection within different density thistle patches. In the main experiment, we sprayed half of test plants in different density patches with fungicide (Fungonil© Bonide, containing chlorothalonil) and half with a water control. Fungal infection rates were very low, so we found no difference in fungal attack between these treatments. However, plants that received the fungicide treatment had significantly faster growth over the season than did the control plants. At the same time, plants in the fungicide treatment had significantly reduced insect herbivory. These results strongly suggest that the fungicide had insecticidal effects and that insect herbivory significantly decreases juvenile Platte thistle growth. Further, damage by insect herbivores tended to be higher for larger plants, and herbivory was variable among different patches. However, plant density did not appear to have a large effect on the amount of insect herbivory that individual juvenile Platte thistle plants received. In the second experiment, we examined germination and survival success in relationship to seed density, and found that germination success was higher in areas of lower seed density. In the third experiment, we tested germination for filled seeds categorized primarily by color variation and size, and found no difference in germination related to either color or seed weight. We conclude that seed density, but not seed quality as estimated by color or size, affects germination success. Further, although herbivory was not significantly affected by plant density at any of the scales examined, insect herbivory significantly reduces the growth and success of juveniles of this characteristic native sand prairie plant.