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Camponotus textorForel is, to date, the only weaver ant recorded from Brazil, and all existing studies on the species are restricted to describing its weaving and nesting behaviors. The aim of this work is to establish the molecular profile of the species. We sampled eight different colonies by sequencing mitochondrial genes (COI, transfer DNA (tRNA), and an intergenic spacer) and the nuclear gene 28S ribosomal DNA (rDNA). We then assessed haplotype diversity and also analyzed distribution patterns of this species based on the correlation between genetic and geographic distances. Our results provide an additional tool for species identification by identifying new regions that can be used as molecular markers for barcoding (such as the intergenic spacer (IGS) and tRNA-Leu). In addition, the phylogenetic analysis revealed that C. textorhas features that could be associated with deep population divergences. We identified a wide range of mitotypes and three distinct groups, suggesting a possible reduction of gene flow between colonies.

Linepithema micans(Forel) is considered to be the main ant species responsible for the spread of Eurhizococcus brasiliensis(Wille), a soil scale that damages vine plants in southern Brazil. In this work, the seasonal life cycle of L. micanswas evaluated in vineyards to define the most appropriate time for the application of toxic baits for control. Ant nests were transported to the laboratory in plastic bags, and individual ants were separated into groups of eggs, larvae, pupae, workers, males, and queens, recording the number of individuals per colony. The seasonal life cycle of L. micansin the vineyards began in spring with the deposition of eggs by queens. During the warm months of the year (spring and summer), it was possible to observe nests consisting primarily of eggs and pupae. During the autumn and winter months, the colonies were composed predominantly of larvae and a reduction in eggs was observed. Because the main control strategy targets the larval stage of the insect, the application of toxic baits for the control of L. micansmust be performed during the winter.

Abstract: Linepithema micans (Forel) (Hymenoptera: Formicidae) is reported to occur from eastern Brazil to central Argentina in pasture or grassland, forest and second growth riparian forest, nesting under stones, rotting wood, and sandy soil. However, information on this species is poor and its ecological interactions and role as pests are unknown. Linepithema humile (Mayr), a closely related species to L. micans, known as the Argentine ant, is native to South America, and was accidentally introduced to several regions of the world. Recent studies have shown that other related species, such as L. micans, could become as pestiferous as L. humile because of its phylogenetic proximity. Samples of L. micans from different habitats in Southern Brazil were characterized by sequencing of the mitochondrial DNA. Sequences were compared to previously obtained sequences from samples of L. humile and the genetic distance and differences in the tRNALeu structure were investigated. Our data identified three haplotypes of L. micans, two of which were observed in ant populations closely associated with the Brazilian ground pearl Eurhizococcus brasiliensis (Hempel) (Hemiptera: Margarodidae), a soil scale that is a serious pest of vineyards. The third haplotype was identified in ants from populations invading residences in urban habitats.

The aim of this study was to select virulent strains of microfungi against Leucoagaricus gongylophorus, a symbiotic fungus cultivated by leaf-cutting ants. The results from in vitroassays showed that microfungal strains had a variable and significant impact on the colony development of L. gongylophorus. Specifically, Trichoderma harzianum, Escovopsis weberiCBS 810.71 and E. weberiA088 were more effective, inhibiting the L. gongylophoruscolonies by 75, 68 and 67%, respectively (P< 0.05) after 15 days. Strain E. weberiA086 and Acremonium kiliensewere less effective: 43 and 26%, respectively (P< 0.05). In spite of the current negative perspective of a microbiological control approach for these ants, the present work discusses the possibility of using mycopathogenic fungi for the control of these insects, and points out the importance of encouraging more studies in this area.The aim of this study was to select virulent strains of microfungi against Leucoagaricus gongylophorus, a symbiotic fungus cultivated by leaf-cutting ants. The results from in vitroassays showed that microfungal strains had a variable and significant impact on the colony development of L. gongylophorus. Specifically, Trichoderma harzianum, Escovopsis weberiCBS 810.71 and E. weberiA088 were more effective, inhibiting the L. gongylophoruscolonies by 75, 68 and 67%, respectively (P< 0.05) after 15 days. Strain E. weberiA086 and Acremonium kiliensewere less effective: 43 and 26%, respectively (P< 0.05). In spite of the current negative perspective of a microbiological control approach for these ants, the present work discusses the possibility of using mycopathogenic fungi for the control of these insects, and points out the importance of encouraging more studies in this area.

Norms for three visual memory tasks, including Corsi's block tapping test and the BEM 144 complex figures and visual recognition, were developed for neuropsychological assessment in Brazilian children. The tasks were measured in 127 children ages 7 to 10 years from rural and urban areas of the States of São Paulo and Minas Gerais. Analysis indicated age-related but not sex-related differences. A cross-cultural effect was observed in relation to copying and recall of Complex pictures. Different performances between rural and urban children were noted.

The blame for the semantic and set-theoretic paradoxes is often placed on self-reference and circularity. Some years ago, Yablo [1985; 1993] challenged this diagnosis, by producing a paradox that's liar-like but does not seem to involve circularity. But is Yablo's paradox really non-circular? In a recent paper, Beall [2001] has suggested that there are no means available to refer to Yablo's paradox without invoking descriptions, and since Priest [1997] has shown that any such description is circular, Beall concludes that Yablo's paradox itself is circular. In this paper, we argue that Beall's conclusion is unwarranted, given that (i) descriptions are not the only way to refer to Yablo's paradox, and (ii) we have no reason to believe that because the description involves self-reference, the denotation of that description is also circular. As a result, for all that's been said so far, we have no reason to believe that Yablo's paradox is circular.

La enfermedad de Cushing tiene baja prevalencia en la población infantil. Generalmente está producida por microadenomas hipofisarios secretores de hormona adrenocorticotropa (ACTH). La sintomatología puede pasar desapercibida largo tiempo, siendo los síntomas más constantes retraso del crecimiento y obesidad. Se presentan 4 pacientes diagnosticados de enfermedad de Cushing en un hospital terciario, desde enero de 1995 a diciembre del 2002. Dos eran chicos y 2 chicas, con edades entre 10 y 15 años. Las primeras manifestaciones fueron estancamiento estatural con rápida ganancia ponderal. El tiempo transcurrido desde el inicio de los síntomas hasta el diagnóstico fue de 2,5-5 años. Todos presentaban facies de “luna llena™ con aumento de grasa cervicodorsal. El cortisol libre urinario estaba elevado en los 4 pacientes. Había desaparecido el ritmo circadiano del cortisol en sangre (3/3), con una supresión de la cortisolemia y cortisoluria a menos del 50 % de los valores basales con dosis altas pero no bajas de dexametasona (2/2). En 3 pacientes se visualizó microadenoma hipofisario en la resonancia magnética (RM) con contraste; en el cuarto no se observó tumor pituitario y se realizó cateterismo de senos petrosos inferiores, mostrando lateralización izquierda de la secreción central de ACTH. Se practicó cirugía transesfenoidal en todos los pacientes: dos están en remisión; un tercero presentó recidiva de la enfermedad y hubo que realizar hipofisectomía total por imposibilidad de resección; en el cuarto paciente la enfermedad fue persistente tras una segunda cirugía y recibió radioterapia hipofisaria. Dos de los 4 pacientes presentan hipopituitarismo secundario.

Three groups of rats (A, B, C) were trained in a T-maze to discriminate between drug- and control solution-induced internal discriminative stimuli. The drugs used to induce discriminative stimuli were: d9-THC, 5.0 mg/kg (Group A); ethanol, 1.2 g/kg (Group B), and amphetamine, 1.0 mg/kg (Group C). After discrimination acquisition several drugs were tested for generalization in each group. Group A was tested with d8-THC, CBD, CBN, ethanol, pentobarbital, chlorpromazine, amphetamine, and apomorphine; only d8-THC and CBN induced d9-THC-like responses. Group B was tested with d9-THC, d8-THC, CBD, CBN, pentobarbital, and amphetamine; pentobarbital induced ethanol-like response. Group C was tested with d9-THC, apomorphine, and ethanol; d9-THC and apomorphine elicited amphetamine-like responses.

Summary In this paper we describe how morphological castes can be distinguished using multivariate statistical methods combined with jackknife estimators of the allometric coefficients. Data from the polymorphic ant,Camponotus rufipes, produced two distinct patterns of allometric variation, and thus two morphological castes. Morphometric analysis distinguished different allometric patterns within the two castes, with overall variability being greater in the major workers. Caste-specific scaling variabilities were associated with the relative importance of first principal component. The static multivariate allometric coefficients for each of 10 measured characters were different between castes, but their relative magnitudes within castes were similar. Multivariate statistical analysis of worker polymorphism in ants is a more complete descriptor of shape variation than, and provides statistical and conceptual advantages over, the standard bivariate techniques commonly used.

Workers and males of the stingless beeScaptotrigona postica emerge from morphologically similar cells. Normally only one bee is reared in each brood cell, but we found that some of the cells, interspersed throughout the brood comb, contained more than one egg. Because these additional eggs produced adult males, they were probably laid by nurse bees (workers) after the queen had oviposited in the cells concerned.

In a parallel, double‐blind study, 12 untreated hypertensive patients received terazosin (2–4 mg/day for 4 weeks), and 12 received placebo during the same period. Systolic and diastolic blood pressure decreased significantly in the terazosin group, from 150 ± 5.0 mmHg systolic and 99.6 ± 2.0 diastolic before treatment, to 134.0 ± 7.0 systolic and 85.6 ± 3.0 mmHg diastolic at week 4 of treatment. No significant blood pressure changes occurred in the placebo group. Blood pressure decrease showed a positive correlation (r = .62 and r = .52 for systolic and diastolic blood pressure, respectively) with the patient's age (P < .05). Total plasma cholesterol decreased 18% in the terazosin group (P < .05) and 9% in the placebo group (P > .05). Urinary dopamine excretion decreased significantly from 692.8 ± 180.0 to 330.5 ± 52.0 μg/24 hours in the terazosin group (P < .05) and showed a nonsignificant increase in the placebo group. Compared with 22 age‐ and sex‐matched healthy volunteers, urinary dopamine excretion in the hypertensive group before treatment was not statistically different (779.3 ± 83.1 μg/24 hours). Dopamine excretion was higher in untreated hypertensive men and in male healthy volunteers compared with women. The decrease of urinary dopamine excretion observed under terazosin treatment could be due to a decrease of kidney dopamine synthesis or release induced by blood pressure reduction, or secondarily to the blockade of kidney α1‐receptors, modulating dopamine excretion. No significant changes were observed in urinary excretion of noradrenaline and adrenaline.

The inhibition of gamma-aminobutyric acid (GABA)-gated chloride currents by the protein kinase C (PKC) activator 4beta-phorbol 12-myristate 13-acetate (PMA) was investigated using recombinant human GABAA receptors expressed in Xenopus oocytes. PMA (5 nM) reduced the GABA response in oocytes expressing the alpha1 beta2 gamma2L receptor construct, as measured by the two-electrode voltage-clamp method. GABA responses declined to approximately 25% of their pretreatment value within 45 min. GABA responses in oocytes expressing a receptor construct from which the known PKC phosphorylation sites were absent, alpha1 beta2(S410A), were comparably inhibited. Phorbol 12-monomyristate (PMM; 5 nM), which does not activate PKC, did not alter the GABA response in either construct, while the PKC inhibitor calphostin C (0.5 microM) prevented the PMA effect. To further investigate PMA inhibition of the GABA response, a GABAA receptor alpha1 subunit/green fluorescent protein (GFP) chimera (alpha1GFP) was used to visualize GABAA receptor distribution. Similar to the wild type constructs, PMA robustly decreased GABA responses in oocytes expressing alpha1GFP beta2 gamma2L and alpha1GFP beta2(S410A) receptor constructs. Following PMA treatment, GFP fluorescence in the oocyte plasma membrane was decreased to approximately 45% of the pretreatment values indicating GABAA receptor internalization. This effect of PMA was prevented by calphostin C and was not produced by PMM. Experiments with bd24, a monoclonal antibody which recognizes an extracellular epitope of the alpha1 subunit, were used to demonstrate that PMA, but not PMM, decreases alpha1 subunit immunoreactivity in the plasma membrane of intact oocytes expressing the alpha1 beta2 gamma2L construct, thus confirming the results obtained with the chimeric receptor. It is concluded that, in Xenopus oocytes, PMA induces an internalization of the GABAA receptor through PKC-mediated phosphorylation of an unidentified protein(s) and that this contributes to the decrease in electrophysiological responses to GABA following PKC activation.