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1.
Neotrop Entomol ; 48(3): 515-521, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30637578

RESUMEN

Nasutitermes corniger (Motschulsky, 1855) (Termitidae: Nasutitermitinae) is an important pest in urban environments and bioinsecticides can be an alternative to its control. Here, we determined the toxicity and repellence of the essential oil (EO) prepared from stems of Aristolochia trilobata L. (Aristolochiaceae) and its major constituents on N. corniger. We also investigated behavioral changes of individuals exposed to limonene. The lethal dose required to kill 50% of N. corniger population (LD50) of EO of A. trilobata was 2.44 µg mg-1. Limonene was the most toxic compound to N. corniger followed by linalool (LD50 = 1.02 and 1.29 µg mg-1, respectively). In addition, all treatments presented median lethal time (LT50) less than 11 h. A. trilobata EO and its constituents showed irritability activity, but only limonene repelled soldiers more than workers. The negative behaviors of N. corniger groups were higher in individuals treated with limonene. A. trilobata EO and its constituents, especially the limonene, are promising for the control of N. corniger due the high toxicity, repellence, and possible disturbance in the colonies.


Asunto(s)
Aristolochia/química , Insecticidas , Isópteros , Aceites Volátiles , Monoterpenos Acíclicos , Animales , Repelentes de Insectos , Limoneno , Monoterpenos , Aceites de Plantas , Pruebas de Toxicidad Aguda
2.
Neotrop Entomol ; 47(6): 808-814, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30094633

RESUMEN

Aggressive behaviour can ensure animal access to local resources. To reduce constant costs in the defence of territories, species could save energy with conflicts avoiding aggression with neighbour or in situations with abundance of resources. In the present study, we analysed the effect of distance among colonies and resource availability on the aggression level and responses to chemical cues of Nasutitermes aff. coxipoensis (Holmgren) (Termitidae: Nasutitermitinae). Manipulation of resource offer was conducted in the field, where nests with different distances were kept without addition of baits (control), with addition of three or 16 sugarcane baits/nest. After 3 months, aggressiveness, linear and Y-shaped trail-following bioassays were carried out with all pairwise combinations of colonies in each treatment. Our results showed that aggressive index of N. aff. coxipoensis was affected by the resource availability. However, individuals from colonies with 0 and 3 baits/nest showed a higher number of fighting with neighbours than those from non-neighbours colonies. Termite workers from colonies without baits (control) followed shorter distance in the linear trails compared to those from colonies with addition of baits. In all treatments, there was no preference of workers in relation to the choice of chemical cues from own or other colonies. The response of intercolonial aggressiveness in N. aff. coxipoensis seems to be resource-dependent. These results may contribute to the comprehension of the use of space by N. aff. coxipoensis and could be useful to explain patterns of termite co-occurrence at different spatial scales, from local (inside the nest-e.g. cohabitation of nests by inquilines) to regional (e.g. around the nest).


Asunto(s)
Agresión , Isópteros/química , Isópteros/fisiología , Animales , Señales (Psicología) , Ecosistema , Comportamiento de Nidificación
3.
Neotrop Entomol ; 47(6): 769-779, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29995283

RESUMEN

Leaf-cutting ants belonging to the genus Atta (Formicidae: Myrmicinae) are important pests in agricultural and forest environments. In the present study, we evaluated the formicidal activity of the essential oil of Pogostemon cablin and its nanoformulation on the leaf-cutting ants: Atta opaciceps (Borgmeier, 1939), Atta sexdens (Linnaeus, 1758), and Atta sexdens rubropilosa Forel, 1908. The nanoformulation was developed by magnetic stirring using polyoxyethylene (36%), pure ethanol (36%), essential oil of P. cablin (18%), and water (10%). Bioassays of acute toxicity by fumigation and behavioral bioassays in treated arenas, with and without choice, were performed. The essential oil of P. cablin and its nanoformulation demonstrated efficient insecticidal activity and irritability to ant species. The concentration required to kill 50% of workers varied from 1.06 to 2.10 µL L-1, with a mean time to death of less than or equal to 42 h. The essential oil of P. cablin and its nanoformulation reduced the displacement and velocity speed of the workers of A. opaciceps and A. sexdens rubropilosa in totally treated arenas. In the bioassays with choices, the three species of ants walked less and at a greater speed on the treated side of arena. This work demonstrates the potential of the essential oil of P. cablin and its nanoformulation to the generation of new formicidal products.


Asunto(s)
Hormigas , Insecticidas , Aceites Volátiles , Pogostemon/química , Animales , Conducta Animal , Pruebas de Toxicidad Aguda
4.
Neotrop Entomol ; 47(6): 750-756, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29982978

RESUMEN

Symbiosis between plants and ants include examples in which the plant provides shelter and/or food for ants that, in turn, act in the defense or in the dispersion of seeds from the host plant. Although traditionally referred as mutualistic, the results of these interactions may vary with the ecological context in which patterns are involved. A range of species have facultative association with Turnera subulata (Turneraceae). Here, using behavioral bioassays, we investigated the effects of the most frequent ant species associated with T. subulata (Brachymyrmex sp.1, Camponotus blandus (Smith), Dorymyrmex sp.1, Crematogaster obscurata Emery, and Solenopsis invicta Buren) in the dispersion of plant host seeds and in the number of seedlings around the associated ant nests. We also evaluated the effects of these ant species in the germination of T. subulata seeds, in the consumption of elaiosome, and in the attractiveness to elaiosome odor. Our results showed that the ant species associated with T. subulata presented variation in the attraction by the odor and in the rate of consumption of the elaiosomes. However, none of the ant species studied contributed significantly to the increase of seed germination and seedling growth. Our results suggest that the consumption of the elaiosome by ant species is not a determinant factor to the success of germination of T. subulata. However, such species could contribute indirectly to seed germination by carrying seeds to sites more fertile to germination. In general, our results help to elucidate the results of ecological interactions involving ants and plants.


Asunto(s)
Hormigas/fisiología , Germinación , Dispersión de Semillas , Turnera/fisiología , Animales , Simbiosis
5.
Sci Total Environ ; 636: 1553-1564, 2018 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-29913616

RESUMEN

Abamectin (ABA) toxicity in fish, amphibian and mammals was already proven, but its effect on birds is almost unknown. Thus, the aim of our study is to assess the impact of exposure to water with ABA for 40 days at predicted environmentally relevant concentrations on the behavior of female Japanese quails (Coturnix coturnix japonica). The three following experimental groups (n = 10 each) were set: "control", quails exposed to drinking water, without ABA, "EC1x" and "EC1000x" (0.31 mg a.i./L and 310.0 a.i./L, respectively; via commercial formulation Kraft® 36EC). The open field test showed anxiolytic response in birds exposed to ABA. These birds did not show locomotor changes or aggressive behavior in the aggressiveness test. Quails exposed to the pesticide did not react to the introduction of an object in the experimental box during the object recognition test, and it suggested perception deficit due to ABA. Moreover, these birds did not recognize the cat (Felix catus) and the vocalization of a hawk (Rupornis magnirostris) as potential predatory threats. These responses also suggest anti-predatory behavior deficit due to the pesticide. Thus, our study is pioneer in showing that water with ABA, at tested concentrations, influences the behavior of C. coturnix japonica, as well as in highlighting the potential impacts of this pesticide on this group of birds.


Asunto(s)
Conducta Animal/efectos de los fármacos , Coturnix/fisiología , Ivermectina/análogos & derivados , Plaguicidas/toxicidad , Animales , Gatos , Femenino , Ivermectina/toxicidad
6.
Neotrop Entomol ; 47(3): 329-335, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28466145

RESUMEN

Organisms acquire energy from environment and must allocate it among different life traits (growth, maintenance and reproduction). Social insects must manage the energy allocation to various levels such as colony growth and caste functions. Here, we addressed the question of whether resource density affects the energy allocation to the number of individuals and caste functions as well as nest's growth rate in the Neotropical termite Nasutitermes aff. coxipoensis (Homgren) (Termitidae: Nasutitermitinae). In a manipulative field experiment, colonies of N. aff. coxipoensis, with known volume, were maintained in plots with three different resource's density (0.32, 0.64 and 1.92 baits/m2) over 3 months. After this period, the number of individuals as well as the caste identity and nest volume were measured. Surprisingly, our results showed that colonies reared in the extremes of resource's density (0.32 and 1.92 baits/m2) produced a higher number of individuals compared with colonies reared with intermediate resource density (0. 64 baits/m2). The mean number of workers increased linearly with resource density; however, the average number of immature was higher in colonies reared with 0.32 baits/m2 compared with colonies reared with 0.64 and 1.92 baits/m2. No significant differences of resource density were observed in the mean number of soldiers, worker/soldier ratio as well as in the nest's growth rate. In conclusion, the resource's density seems to play an important role in determining the investment of energy in the number of individuals and caste in N. aff. coxipoensis colonies.


Asunto(s)
Isópteros/fisiología , Animales , Brasil , Ecosistema , Metabolismo Energético , Densidad de Población
7.
Braz. j. biol ; 77(3): 519-526, July-Sept. 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-888795

RESUMEN

Abstract Habitat fragmentation is considered to be one of the biggest threats to tropical ecosystem functioning. In this region, termites perform an important ecological role as decomposers and ecosystem engineers. In the present study, we tested whether termite community is negatively affected by edge effects on three fragments of Brazilian Atlantic Rainforest. Termite abundance and vegetation structure were sampled in 10 transects (15 × 2 m), while termite richness, activity, and soil litter biomass were measured in 16 quadrants (5 × 2 m) at forest edge and interior of each fragment. Habitat structure (i.e. number of tree, diameter at breast height and soil litter biomass) did not differ between forest edge and interior of fragments. Termite richness, abundance and activity were not affected by edge effect. However, differences were observed in the β diversity between forest edge and interior as well as in the fragments sampled. The β diversity partitioning indicates that species turnover is the determinant process of termite community composition under edge effect. Our results suggest that conservation strategies should be based on the selection of several distinct sites instead of few rich sites (e.g. nesting).


Resumo A fragmentação do habitat é considerada uma das maiores ameaças para o funcionamento do ecossistema tropical. Nesta região, os cupins desempenham um papel ecológico importante como decompositores e engenheiros do ecossistema. No presente estudo, testamos se comunidades de cupins são negativamente afetadas pelo efeito de borda em três fragmentos de Mata Atlântica. Para isso, foram amostrados a abundância de cupins e a estrutura da vegetação em 10 transectos (15 × 2 m), enquanto a riqueza, abundância de cupins e biomassa da serrapilheira foram amostrados em 16 parcelas (5 × 2 m) na borda e no interior de cada um dos três fragmentos. A estrutura do habitat (número de árvores, diâmetro à altura do peito e biomassa da serrapilheira) não diferiu entre a borda e o interior dos fragmentos. A riqueza, abundância e atividade dos cupins também não foram afetados pelo efeito de borda. No entanto, foram observadas diferenças na diversidade β entre borda e interior dos fragmentos, bem como nos fragmentos amostrados. O particionamento da diversidade β indicou que a substituição de espécies ("turnover") é o processo determinante da composição da comunidade de cupins sob efeito de borda. Nossos resultados sugerem que as estratégias de conservação devem ser baseadas na seleção de locais distintos em vez de poucos locais (via processo de aninhamento - "nesting").


Asunto(s)
Animales , Isópteros , Biodiversidad , Bosque Lluvioso , Brasil
8.
Braz J Biol ; 77(3): 519-526, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27683814

RESUMEN

Habitat fragmentation is considered to be one of the biggest threats to tropical ecosystem functioning. In this region, termites perform an important ecological role as decomposers and ecosystem engineers. In the present study, we tested whether termite community is negatively affected by edge effects on three fragments of Brazilian Atlantic Rainforest. Termite abundance and vegetation structure were sampled in 10 transects (15 × 2 m), while termite richness, activity, and soil litter biomass were measured in 16 quadrants (5 × 2 m) at forest edge and interior of each fragment. Habitat structure (i.e. number of tree, diameter at breast height and soil litter biomass) did not differ between forest edge and interior of fragments. Termite richness, abundance and activity were not affected by edge effect. However, differences were observed in the ß diversity between forest edge and interior as well as in the fragments sampled. The ß diversity partitioning indicates that species turnover is the determinant process of termite community composition under edge effect. Our results suggest that conservation strategies should be based on the selection of several distinct sites instead of few rich sites (e.g. nesting).


Asunto(s)
Biodiversidad , Isópteros , Bosque Lluvioso , Animales , Brasil
9.
J Anim Physiol Anim Nutr (Berl) ; 99(6): 1149-60, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25846129

RESUMEN

Whole oilseeds such as soya beans have been utilized in dairy rations to supply additional fat and protein. However, antinutritional components contained in soya beans, such as trypsin inhibitors and haemagglutinins (lectins) may alter digestibility of nutrients and consequently affect animal performance. The objective of the present experiment was to quantify the effect of different levels of whole raw soya beans in diets of dairy cows on nutrient intake, total tract digestion, nutrient balances and milk yield and composition. Sixteen mid to late-lactation cows (228 ± 20 days in milk; mean ± SD) were used in four replicated 4 × 4 Latin square design experiment with 21-d periods. Cows were assigned to each square according to milk yield and DIM. The animals were randomly allocated to treatments: control (without soya beans addition; CO), WS9, WS18 and WS27, with addition of 9%, 18% and 27% of whole raw soya bean in diet on a dry matter (DM) basis respectively. All diets contained identical forage and concentrate components and consisted of maize silage and concentrate based on ground corn and soya beans at a ratio of 60:40. There were no differences in OM, CP, NDF and NEL intakes (kg/day and MJ/day) among the treatments (p > 0.05). However, DM and NFC intakes were negatively affected (p = 0.04 and p < 0.01, respectively) and ether extract (EE) intake was positively affected (p < 0.01). Total tract digestion increased linearly with whole raw soya beans for EE (p < 0.01) and NDF (p = 0.01). The excretion (kg/day) of digested soya beans grains increased linearly according to addition of whole raw soya beans. However, the nutritive characteristics of excreted grains were not altered. Milk (kg), milk lactose (kg) and protein (kg) yield decreased linearly (p < 0.01, p < 0.01 and p = 0.04, respectively) milk fat content (%) increased linearly (p < 0.01) with whole raw soya beans inclusion. Increasing addition of whole raw soya beans affected milk fatty acid profile with a linear decrease of cis-9-trans 11CLA and total saturated FA; and linear increase of total unsaturated and C18:3 FA. Energy balance was positively affected (p = 0.03) by whole raw soya beans as well as efficiency of NEL milk/DE intake (p = 0.02). Nitrogen balance and microbial protein synthesis were not affected by whole raw soya beans. Increasing doses of whole raw soya beans decreased dry matter intake and milk yield, however, led to an increase of unsaturated acids in milk and higher milk fat concentration.


Asunto(s)
Alimentación Animal/análisis , Dieta/veterinaria , Digestión/fisiología , Tracto Gastrointestinal/fisiología , Glycine max/química , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Bovinos , Femenino
10.
Archivos de zootecnia ; 61: 67-78, 2012.
Artículo en Portugués | LILACS, MTYCI | ID: biblio-948638

RESUMEN

O carrapato bovino Riphicephalus microplus (Acari: Ixodidae) constitui um dos grandes problemas enfrentado pelos pecuaristas de várias partes do mundo. No Brasil este ectoparasita causa grandes prejuízos à bovinocultura devido ao processo de hematofagia e pela transmissão de agentes patogênicos nos animais hospedeiros. Diante dessa situação os produtores normalmente aplicam carrapaticidas organossintéticos de forma indiscriminada. Este método normalmente resulta em: intoxicação dos animais e dos aplicadores, resíduos de carrapaticidas nos produtos de origem animal, resistência dos carrapatos aos carrapaticidas químicos e poluição ambiental. Uma alternativa para diminuir esses problemas é uso de biocarrapaticidas de origem botânica. Os pesticidas botânicos são produtos naturais derivados do metabolismo secundário das plantas. Esse metabolismo produz uma grande diversidade de compostos com ação carrapaticida que podem ser explorados através do uso de óleos essenciais ou como modelo para síntese de pesticidas sintéticos. A necessidade de métodos mais seguros, menos agressivos ao homem e ao meio ambiente, tem estimulado a busca de novos carrapaticidas a partir de produtos vegetais. Assim, acredita-se que o uso de óleos essenciais de plantas medicinais e aromáticas de uma forma isolada ou associada pode reduzir: a velocidade do desenvolvimento da resistência dos carrapatos aos carrapaticidas, os resíduos nos produtos de origem animal e a toxicidade para os animais, aplicadores e meio ambiente.


Asunto(s)
Plantas Medicinales , Aceites Volátiles , Brasil , Rhipicephalus
11.
Child Care Health Dev ; 37(2): 261-5, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20637023

RESUMEN

BACKGROUND: West syndrome (WS), an age-specific epilepsy of infancy and early childhood, considered of poor prognosis, may have remission. With the objective of describing the clinical features, treatment and outcome of the children with WS followed in a Latin American country, we devised a retrospective study. METHODS: Infants with recurrent spasms, and typical or atypical hypsarrhythmia on electroencephalography (EEG) were included, and their medical report reviewed with particular interest on therapy (anti-epileptic drug, steroids) and outcome. Short-term (remission of spasms up to 6 months after the beginning) and long-term outcome (development and seizure status over the age of 2 years) were focused. RESULTS: Of the 37 selected infants, most (29/37, 78.3%) were classified as symptomatic, and neonatal history of hypoxia (10/29) was the most frequent etiology. The majority had a typical hypsarrhythmia EEG pattern. Most used a combination of anti-epileptic drugs and steroids. A favourable short-term outcome occurred in 20 infants, but only three had normal development and were seizure free after the age of 2 years. CONCLUSION: Early seizure remission is not assurance of normal final outcome in WS.


Asunto(s)
Espasmos Infantiles/diagnóstico , Edad de Inicio , Anticonvulsivantes/uso terapéutico , Discapacidades del Desarrollo/etiología , Femenino , Glucocorticoides/uso terapéutico , Humanos , Lactante , Masculino , Pronóstico , Inducción de Remisión , Estudios Retrospectivos , Espasmos Infantiles/tratamiento farmacológico , Espasmos Infantiles/etiología , Resultado del Tratamiento
12.
Neotrop Entomol ; 40(6): 677-81, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-23939274

RESUMEN

In Hymenoptera, midgut changes begin in the last instar. At this stage, the larval epithelial digestive cells degenerate, leaving only the basal membrane and the regenerative cells which will develop into a new epithelium during the pupal stage and in the adult. Epithelium renewal is followed by changes in volume and shape of the midgut. Morphometric analysis of digestive cells and total midgut volume of Melipona quadrifasciata anthidioides (Lepeletier) were conducted to verify whether cell volume increase are sufficient to account for the total midgut volume increase that occurs during metamorphosis. An increase in midgut volume was verified in spite of the scarcity of cell proliferation found during metamorphosis. At the end of metamorphosis, the increase in cell volume was not sufficient to explain the increase in volume of the midgut, indicating that an increase in the number of digestive cells is apparently necessary. Nevertheless, the mechanism by which regenerative cells reconstitute the epithelium during metamorphosis remains unknown.


Asunto(s)
Abejas/anatomía & histología , Abejas/crecimiento & desarrollo , Metamorfosis Biológica , Animales , Sistema Digestivo/anatomía & histología , Sistema Digestivo/crecimiento & desarrollo
13.
Acta Trop ; 113(2): 180-9, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19879849

RESUMEN

Insecticide resistance is one of the main problems in vector control programs. Because insects have developed resistance to all classes of available chemical insecticides, a proper surveillance and management of resistance in areas where these compounds are being utilized is crucial for the success of control programs. Since the mechanisms and molecular bases of resistance are various, they must be characterized to allow efficient monitoring strategies. Here we report the establishment of an Aedes aegypti strain resistant to temephos, named RecR, selected under laboratory conditions. The parental A. aegypti population was obtained from eggs collected in an area where temephos had been used for 8 years, and presented a baseline resistance ratio (RR) of 7. After 17 generations under selective pressure, the RR has increased to 180. Biochemical assays indicate that metabolic mechanisms are involved on temephos resistance in the selected strain. These experiments showed that, compared to the susceptible colony Rockefeller, RecR present higher activity of glutathione S-transferases (GSTs), alpha- and beta-esterases, and, to a lesser degree, mixed function oxidases (MFO). At the 14th or 17th generations, there was no cross resistance of these insects to deltamethrin, cypermethrin and malathion, while a low resistance level (RR=3) was observed for pyriproxyfen, a juvenile hormone analogue. Experiments on resistance reversal, performed through three different field simulated schemes using the resistant strain, showed that temephos susceptibility can be recovered. The establishment of an A. aegypti colony resistant to temephos is extremely valuable for a deeper understanding of resistance mechanisms and thus for further improvements in control strategies against this vector. With the urgent need on improving methodologies to monitor resistance, molecular studies such as microarrays, and resistant colonies such as RecR will certainly hasten such studies.


Asunto(s)
Aedes/efectos de los fármacos , Aedes/genética , Resistencia a los Insecticidas , Insecticidas/farmacología , Temefós/farmacología , Aedes/crecimiento & desarrollo , Animales , Animales de Laboratorio , Bioensayo , Brasil , Evolución Molecular Dirigida , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Insectos Vectores/efectos de los fármacos , Insectos Vectores/genética , Resistencia a los Insecticidas/genética
14.
Bull Entomol Res ; 99(6): 603-9, 2009 12.
Artículo en Inglés | MEDLINE | ID: mdl-19302722

RESUMEN

Why is the ground brown, when detritivores and decomposers have the numbers and ability to speed up the turnover of dark-coloured soil organic carbon? We consider this soil analogue to the 'green world' hypothesis measuring in the field how fast termites occupied cellulosic baits of varying quantity and quality and how predation risks by ants affect such encounters. Single baits with ants were occupied by termites later than triple baits without ants, implying that termites may spend longer searching for suitable food than feeding on it, thereby delaying decomposition rates of both chosen and neglected items. Because termites' feeding speeds up dissimilation of polymers by decomposers, such results may imply that bottom-up and top-down forces, ultimately, impair carbon processing and release from soil. We argue that the ground is brown partly because of delays imposed upon termites' use of resources by bottom-up and top-down forces.


Asunto(s)
Carbono/metabolismo , Cadena Alimentaria , Isópteros/fisiología , Suelo , Animales , Hormigas/fisiología , Conducta Alimentaria , Conducta Predatoria , Factores de Tiempo
15.
Biophys Chem ; 134(3): 246-53, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18346834

RESUMEN

Porcine S100A12 is a member of the S100 proteins, family of small acidic calcium-binding proteins characterized by the presence of two EF-hand motifs. These proteins are involved in many cellular events such as the regulation of protein phosphorylation, enzymatic activity, protein-protein interaction, Ca2+ homeostasis, inflammatory processes and intermediate filament polymerization. In addition, members of this family bind Zn2+ or Ca2+ with cooperative effect on binding. In this study, the gene sequence encoding porcine S100A12 was obtained by the synthetic gene approach using E. coli codon bias. Additionally, we report a thermodynamic study of the recombinant S100A12 using circular dichroism, fluorescence and isothermal titration calorimetry. The results of urea and temperature induced unfolding and refolding processes indicated a reversible two-state process. Also, the ANS fluorescence studies showed that in presence of divalent ions the protein exposes hydrophobic sites which could facilitate the interaction with other proteins and trigger the physiological responses.


Asunto(s)
Pliegue de Proteína , Proteínas S100/química , Proteínas S100/metabolismo , Porcinos/metabolismo , Animales , Calcio/química , Calcio/metabolismo , Calorimetría , Dicroismo Circular , Expresión Génica , Concentración de Iones de Hidrógeno , Unión Proteica , Desnaturalización Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/clasificación , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Proteínas S100/clasificación , Proteínas S100/aislamiento & purificación , Temperatura , Termodinámica , Zinc/química , Zinc/metabolismo
16.
Braz. j. biol ; 67(4): 611-617, Nov. 2007. graf, tab
Artículo en Inglés | LILACS | ID: lil-474183

RESUMEN

Several bromeliads species store water and organic substrates, allowing the establishment of phytotelmata and associated fauna on their leaves. In this study, we sampled 70 individuals of Vriesea sp. (Carrière) (Bromeliaceae), in rupestrian fields in the Serra de Ouro Branco-MG, Brazil. The relationships between invertebrate species richness and abundance and size of bromeliads were tested using multiple regression. We found 19 species associated with bromeliads, mainly Diptera larvae. The abundance of the phytotelmate fauna increased principally in relation to the volume of water in the bromeliad reservoir. Phytotelmata richness was affected principally by diameter of the reservoir. There was a significant relationship between the abundance and richness of invertebrates associated with leaves with diameter and height of the plant. Invertebrate richness was better explained by abundance of individuals. These results suggest that the increase of richness was attended by higher numbers of microhabitats and more space for colonization of bigger bromeliads. Additionally, there was more chance of sampling different species in locales with greater abundance of individuals.


Muitas espécies de bromélias são capazes de armazenar água e detritos, permitindo o estabelecimento de comunidades associadas aos seus tanques de água e às suas folhas. Neste trabalho, foram amostrados 70 indivíduos de Vriesea sp. (Carrière) (Bromeliaceae), em uma área de campo rupestre na Serra de Ouro Branco-MG, Brasil. Foi testada a relação entre a riqueza e a abundância das comunidades de invertebrados associados e o tamanho da bromélia. Em todos os casos foram utilizadas análises de regressão linear múltipla. Foram amostradas 19 espécies, principalmente larvas de Diptera associadas à bromélia. A abundância da fauna fitotelmata aumentou principalmente com o volume de água no reservatório da bromélia. Já a riqueza de fitotelmata foi relacionada principalmente com o diâmetro da planta. No entanto, a abundância e riqueza dos invertebrados associados às folhas apresentaram relação significativa com a altura e o diâmetro da planta. A riqueza de invertebrados foi mais bem explicada pela abundância de indivíduos do que pelo tamanho da bromélia. Estes resultados sugerem que o aumento da riqueza pode ter sido resultante do maior número de microhabitats e de espaço para colonização em bromélia de maior tamanho. Além disso, houve maior chance de amostrar espécies diferentes em locais com maior abundância de indivíduos.


Asunto(s)
Animales , Bromelia/anatomía & histología , Ecosistema , Invertebrados/fisiología , Brasil , Densidad de Población
17.
Braz J Biol ; 67(4): 611-7, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18278311

RESUMEN

Several bromeliads species store water and organic substrates, allowing the establishment of phytotelmata and associated fauna on their leaves. In this study, we sampled 70 individuals of Vriesea sp. (Carrière) (Bromeliaceae), in rupestrian fields in the Serra de Ouro Branco-MG, Brazil. The relationships between invertebrate species richness and abundance and size of bromeliads were tested using multiple regression. We found 19 species associated with bromeliads, mainly Diptera larvae. The abundance of the phytotelmate fauna increased principally in relation to the volume of water in the bromeliad reservoir. Phytotelmata richness was affected principally by diameter of the reservoir. There was a significant relationship between the abundance and richness of invertebrates associated with leaves with diameter and height of the plant. Invertebrate richness was better explained by abundance of individuals. These results suggest that the increase of richness was attended by higher numbers of microhabitats and more space for colonization of bigger bromeliads. Additionally, there was more chance of sampling different species in locales with greater abundance of individuals.


Asunto(s)
Bromelia/anatomía & histología , Ecosistema , Invertebrados/fisiología , Animales , Brasil , Densidad de Población
18.
Int J Immunogenet ; 33(2): 111-5, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16611255

RESUMEN

A descriptive case study was performed on 75 patients with NF1 (neurofibromatosis type 1) from the CNNF (Brazil) database. Serum IgE levels were determined using the IgE radioimmunosorbent test, with the reference values of 75-502 IU mL(-1). The patients were divided into groups, with 25 patients presenting plexiform neurofibromas, 25 presenting neurofibromas and 25 presenting no neurofibromas. The purposes of this study were to determine the serum IgE levels of patients with NF1 presenting plexiform neurofibromas, neurofibromas and no neurofibromas, as well as to determine possible correlations between serum IgE levels and the size of the plexiform neurofibromas and neurofibromas presented by these patients. Elevated serum IgE levels were observed in all the patient groups. We did not observe a correlation between IgE levels and age in these patients; however, we did observe correlations between IgE levels and neurofibroma and plexiform neurofibroma size. We suggest further studies to confirm these results and to investigate in greater depth the possible role of IgE in the development and growth of neurofibromas and plexiform neurofibromas in NF1.


Asunto(s)
Inmunoglobulina E/sangre , Neurofibromatosis 1/inmunología , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Neurofibromatosis 1/sangre , Neurofibromatosis 1/diagnóstico , Factores Sexuales
19.
Acta Crystallogr D Biol Crystallogr ; 57(Pt 12): 1877-80, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11717503

RESUMEN

Active cytosolic (CT) Cu,Zn superoxide dismutase from Schistosoma mansoni (SmCTSOD) was recovered after thrombin cleavage of a glutathione-S-transferase linked fusion protein (GST-SmCTSOD) expressed in the presence of the active-site metals. Crystals have been obtained in two space groups, P2(1)2(1)2(1) and P2(1). The former have unit-cell parameters a = 74.64, b = 78.24, c = 95.18 A and typically diffract to 2.2 A. The monoclinic crystals have unit-cell parameters a = 39.27, b = 95.08, c = 78.41 A, beta = 103.55 degrees and diffract to at least 1.55 A. The calculated solvent content of the crystals is compatible with two dimers of SmCTSOD in the asymmetric unit in both cases. Molecular-replacement solutions have been obtained for both crystal forms and show that slight distortions in the crystal packing relate one form to the other.


Asunto(s)
Schistosoma mansoni/enzimología , Superóxido Dismutasa/química , Animales , Cristalización , Cristalografía por Rayos X , Citosol/enzimología , Modelos Moleculares , Conformación Proteica , Proteínas Recombinantes/química , Superóxido Dismutasa/biosíntesis
20.
Arq Neuropsiquiatr ; 59(3-B): 812-4, 2001 Sep.
Artículo en Portugués | MEDLINE | ID: mdl-11593290

RESUMEN

In the last few years we have been able to diagnose a larger number of cases of Moebius syndrome, perhaps due to its increased incidence--since a number of environmental factors have been related to the genesis of the syndrome. Out of the cases evaluated in two specialized ambulatory, it is worthwhile to mention one of them due to an uncommon association with cortical heterotopy, among others malformations.


Asunto(s)
Encefalopatías/diagnóstico , Síndrome de Mobius/diagnóstico , Encéfalo/anomalías , Encéfalo/patología , Encefalopatías/complicaciones , Preescolar , Humanos , Imagen por Resonancia Magnética , Masculino , Síndrome de Mobius/complicaciones
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