Behavioral Repertoire of Basal Fungus-Growing Ant Sexuals (Hymenoptera: Formicidae) in the Parental Nest

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Basal temperature and thermal sum in phenological phases of nectarine and peach cultivars

O objetivo deste trabalho foi avaliar a temperatura basal, a soma térmica acumulada em diferentes fases fenológicas, a duração das fenofases, a produtividade e a sazonalidade do ciclo de uma cultivar de nectarina e de 14 cultivares de pêssego, entre 2006 e 2009. As fases fenológicas consideradas foram: poda-brotação; brotação-florescimento, da gema inchada até a flor aberta; florescimento-frutificação, da queda das pétalas até o fruto médio; e maturação. As temperaturas basais mínimas obtidas foram: poda-brotação, 8°C, independentemente das cultivares avaliadas; brotação-florescimento, 10°C, com exceção de 'Cascata 968', que necessitou de Tb de 8°C; florescimento-frutificação, 12°C, exceto 'Oro Azteca', que necessitou de Tb de 14°C; maturação, 14°C, com exceção de 'Sunblaze', 'Diamante Mejorado' e 'Precocinho', com Tb de 12°C. Para a maioria das cultivares, as temperaturas basais máximas foram de 30, 34, 34 e 28ºC, nas fases poda-brotação, brotação-florescimento, florescimento-frutificação e maturação, respectivamente. 'Turmalina', 'Marli' e 'Tropic Beauty' apresentaram produtividade média de 3.945,0, 3.969,3 e 3.954,0 kg ha-1, em 2009, respectivamente, enquanto a nectarineira 'Sunblaze' produziu em torno de 3.900 kg ha-1 em 2008 e 2009. As cultivares diferiram quanto ao ciclo total e quanto às somas térmicas acumuladas que variaram, respectivamente, de 245 dias e 1.881,4 graus-dia em 'Oro Azteca', a 144 dias e 1.455,7 graus-dia em 'Precocinho'.

In vitro basal and metabolism-mediated cytotoxicity of flavonoids

The purpose of this study was to compare the basal cytotoxicity and metabolism-mediated cytotoxicity of kaempferol, quercetin and rutin. McCoy cells were exposed to various concentrations of the flavonols with and without the S9 system. The neutral red uptake assay was used to determine viability after 24 h at 35-37 degrees C. Dose-response curves were established for each flavonol in the presence and absence of external metabolizing systems. Kaempferol and quercetin were cytotoxic and provoked a dose-dependent decrease in cell viability, without the S9 system. The hepatic S9 microsomal fraction metabolized these compounds to less cytotoxic metabolites. In contrast, rutin at 500 mu g/ml failed to produce any overt signs of toxicity in either assay. (c) 2005 Elsevier Ltd. All rights reserved.

Exposure to chronic stress increases the locomotor response to cocaine and the basal levels of corticosterone in adolescent rats

Repeated exposure to stress results in augmentation in the locomotor response to psychostimulant drugs. We investigated the locomotor response to a novel environment or cocaine [ 10 mg/kg, intraperitoneally (i.p.)] and basal corticosterone levels in male adolescent rats exposed to chronic restraint or variable stress. Animals in the chronic restraint group were restrained for 1 hour daily. The chronic variable stress protocol consisted of exposure to different stressors twice a day in random order. Chronic restraint and variable stress regimens began simultaneously on postnatal day (P) 25 and were applied for 10 days. During this period the control group was left undisturbed except for cleaning the cages. Three days after the last exposure to stress, cocaine- and novelty-induced locomotion were recorded in an activity cage. Plasma corticosterone levels were determined in a subset of stress and control animals. Exposure to both chronic restraint and variable stress increased cocaine- induced locomotion and basal corticosterone plasma levels, while no change was observed in the response to a novel environment. Moreover, rats exposed to variable stress displayed the greatest locomotor response following a challenge dose with cocaine when compared to control and chronic restraint stress groups. This observation indicates that the stress regimen is relevant to the degree of stress-induced sensitization to cocaine.

Corrective eyeglasses and medial canthal basal cell carcinoma: a case-control study

Background Corrective eyeglasses are frequently worn by adults, particularly at older ages. Their lenses and frames provide ultraviolet protection. Medial canthal basal cell carcinomas are infrequent (38%), and their relation with the use of corrective glasses was not yet investigated. Objectives To assess the prevalence of corrective eyeglasses use in individuals with medial canthal basal cell carcinoma. Methods Case-control study using two controls matched by age, gender, and ethnicity for each case. Cases were patients with medial canthal basal cell carcinoma, and controls were patients with basal cell carcinoma elsewhere on the face. The prevalence of major risk variables was estimated and adjusted by conditional multiple logistic regression. Results Fifty cases and 100 controls were assessed. The mean patient age was 69.7 years, and 54% of the subjects were females. No difference regarding the eyeglasses use or use duration was found between groups. However, when visual defects were separately evaluated, eyeglasses for myopia correction were independently associated with lower risk of medial canthal basal cell carcinoma development (OR = 0.26; P = 0.03), what can be related to long term local photoprotection. Conclusion The use of eyeglasses for myopia correction is associated with lower prevalence of medial cantal basal cell carcinoma. Risk-reducing mechanisms should be elucidated.

Cell blocks allow reliable evaluation of expression of basal (CK5/6) and luminal (CK8/18) cytokeratins and smooth muscle actin (SMA) in breast carcinoma

Objective:Gene expression studies have revealed several molecular subtypes of breast carcinoma with distinct clinical and biological behaviours. DNA microarray studies correlated with immunohistochemical profiling of breast carcinomas using cytokeratin (CK) markers, Her2/neu, oestrogen receptor (ER), and basal myoepithelial cell markers have identified five breast tumour subtypes: (i) luminal A (ER+; Her2/neu-), (ii) luminal B (ER+; Her2/neu+), (iii) Her2 overexpression (ER-; Her2/neu+), (iv) basal-like (ER-; Her2/neu-, CK5/6 and 14+), and (v) negative for all markers. Luminal carcinomas express cytokeratins in a luminal pattern (CK8/18), and the basal-like type expresses CK5/6 and CK14 or basal epithelial cell markers. CK5/6, CK8/18, and smooth muscle actin (SMA) expression were assessed in cell blocks and compared with expression in surgical specimens.Methods:Sixty-two cases of breast carcinoma diagnosed by fine needle aspiration cytology with cell blocks and available surgical specimens were included. Cell blocks containing at least 10 high-power fields each with at least 10 tumour cells and surgical specimens were immunostained for CK5/6, CK8/18 and SMA.Results:Percentage sensitivity, specificity, positive predictive value, negative predictive value and accuracy were, respectively, 77, 100, 100, 92 and 94 for CK5/6; 98, 66, 96, 80 and 95 for CK8/18; and 92, 96, 85, 98 and 95 for SMA.Conclusion:The identification of CK5/6, CK8/18 and SMA by immunohistochemistry in cell blocks can be a reliable method that yields results close to those obtained in surgical specimens, and can contribute to the classification of breast carcinomas with luminal and basal expression patterns, providing helpful information in the choice of treatment and in the evaluation of prognostic and predictive factors.

First evidence of an intimate symbiotic association between fungi and larvae in basal attine ants

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Cytogenetic characterisation of the ornamental freshwater fish, Piabucus melanostomus (Iguanodectinae) from Brazilian wetlands and its relation with species of Characidae basal group

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Dominance and Subordination Interactions Among Nestmates in Pre and Post-Emergence Phases of the Basal Eusocial Wasp Mischocyttarus (Monogynoecus) montei (Hymenoptera, Vespidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

2,6-Di-hidroxiacetofenona e tipo de corte basal no enraizamento de estacas semi-lenhosas de pessegueiro Okinawa

A propagação do pessegueiro (Prunus persica) no Brasil é baseada na enxertia sobre porta-enxertos oriundos de sementes. Outros métodos de propagação de frutíferas poderiam ser utilizados para o pessegueiro visando obtenção de materiais de melhor qualidade. Neste trabalho objetivou-se avaliar o efeito do 2,6-di-hidroxiacetofenona aplicado previamente ao ácido indol-butírico em estacas semi-lenhosas de pessegueiro da cultivar Okinawa preparadas com diferentes tipos de corte basal. Foram coletados ramos do porta-enxerto Okinawa em dezembro de 2001 para o preparo das estacas sem folhas, com 12cm de comprimento, 7mm de diâmetro, quatro gemas e diferentes tipos de cortes basais (corte longitudinal, corte lateral e corte da casca) tratado-as na base com 0 e 300mg L-1 de 2,6-di-hidroxiacetofenona por 4h em aeração (oxigenação) e depois com 2500mg L-1 ácido indol-butírico por 5s. As estacas foram plantadas em bandejas de poliestireno expandido (72 células) com vermiculita fina e colocadas em casa de nebulização por 45 dias. A aplicação de 300mg L-1 de 2,6-DHAP e a realização de lesões nas bases das estacas foram eficientes para aumentar o enraizamento das estacas semi-lenhosas do pessegueiro Okinawa , demonstrando que estas técnicas podem ser utilizadas para a propagação de pessegueiro por estaquia.

Calcium bioavailability from the kale (Brassica-oleracea) consumed as a complement of a basal rice and bean diet

The bioavailability of calcium from the kale (Brassica oleracea var. acephala) consumed as a complement of a basal rice and bean diet was studied. Three groups of diets, two controls and one experimental were fed to Wistar female rats. The protein source of the first control was casein and of the second, a mixture of bean and rice. To both groups, graded levels of CaCO3 were added. The experimental diet was similar to the second control, except that CaCO3 was substituted for kale supplying the same amount of calcio. At 35 days of experimental period, they were killed and the calcium and phosphorus were determined in the right femur. The results indicated that the calcium from the kale is better utilized than that of the CaCO3. There was no significant difference in the concentration of calcium in the soft tissues studied among three dietary groups. Considering the high concentration and availability of calcium from the kale its consumption as a complement of the basal rice and bean diet may be recommended as a cheap and good source of this mineral.

Intraspecific variability in the basal metabolic rate: Testing the food habits hypothesis

Several competing hypotheses attempt to explain how environmental conditions affect mass-independent basal metabolic rate (BMR) in mammals. One of the most inclusive and yet debatable hypotheses is the one that associates BMR with food habits, including habitat productivity. These effects have been widely investigated at the interspecific level under the assumption that for any given species all traits are fixed. Consequently, the variation among individuals is largely ignored. Intraspecific analysis of physiological traits has the potential to compensate for many of the pitfalls associated with interspecific analyses and, thus, to be a useful approach for evaluating hypotheses regarding metabolic adaptation. In this study, we investigated the effects of food quality, availability, and predictability on the BMR of the leaf-eared mouse Phyllotis darwini. BMR was measured on freshly caught animals from the field, since they experience natural seasonal variations in environmental factors ( and, hence, variations in habitat productivity) and diet quality. BMR was significantly correlated with the proportion of dietary plants and seeds. In addition, BMR was significantly correlated with monthly habitat productivity. Path analysis indicated that, in our study, habitat productivity was responsible for the observed changes in BMR, while diet per se had no effect on this variable.