Dominance hierarchies and social status ascent opportunity: Anticipatory behavioral and physiological adjustments in a Neotropical cichlid fish

In this work we characterized the social hierarchy of non-reproductive individuals of Cichlasoma dimerus (Heckel, 1840). independently for both sexes, and its relationship to the opportunity for social status ascent. Female and male individuals who were located on the top rank of the social hierarchy, ascended in social status when the opportunity arose, therefore indicating that dominance is directly correlated with social ascent likelihood. Dominance was positively correlated with size in males but not in females, suggesting for the latter a relationship with intrinsic features such as aggressiveness or personality rather than to body and/or ovarian size. Physiological and morphometrical variables related to reproduction, stress and body color were measured in non-reproductive fish and correlated with dominance and social ascent likelihood. Dominance was negatively correlated with plasma cortisol levels for both sexes. No correlation with dominance was found for androgen plasma levels (testosterone and 11-ketotestosterone). No correlation was detected between dominance and the selected morphological and physiological variables measured in females, suggesting no reproductive inhibition in this sex at a physiological level and that all females seem to be ready for reproduction. In contrast, social hierarchy of non-reproductive males was found to be positively correlated with follicle stimulating hormone (FSH) pituitary content levels and gonadosomatic indexes. This suggests an adaptive mechanism of non reproductive males, adjusting their reproductive investment in relation to their likelihood for social status ascent, as perceived by their position in the social hierarchy. This likelihood is translated into a physiological signal through plasma cortisol levels that inhibit gonad investment through pituitary inhibition of FSH, representing an anticipatory response to the opportunity for social status ascent. (C) 2012 Elsevier Inc. All rights reserved.

Computerized imaging analysis of seedlings for assessment of physiological potential of wheat seeds

Nowadays, image analysis is one of the most modern tools in evaluating physiological potential of seeds. This study aimed at verifying the efficiency of the seedling imaging analysis to assess physiological potential of wheat seeds. The seeds of wheat, cultivars IAC 370 and IAC 380, each of which represented by five different lots, were stored during four months under natural environmental conditions of temperature (T) and relative humidity (RH), in municipality of Piracicaba, Stated of São Paulo, Brazil. For this, bimonthly assessments were performed to quantify moisture content and physiological potential of seeds by means of tests of: germination, first count, accelerated aging, electrical conductivity, seedling emergence, and computerized analysis of seedlings, using the Seed Vigor Imaging System (SVIS®). It has been concluded that the computerized analyses of seedling through growth indexes and vigor, using the SVIS®, is efficient to assess physiological potential of wheat seeds.

Double-Stranded RNA-Activated Protein Kinase Is a Key Modulator of Insulin Sensitivity in Physiological Conditions and in Obesity in Mice

The molecular integration of nutrient-and pathogen-sensing pathways has become of great interest in understanding the mechanisms of insulin resistance in obesity. The double-stranded RNA-dependent protein kinase (PKR) is one candidate molecule that may provide cross talk between inflammatory and metabolic signaling. The present study was performed to determine, first, the role of PKR in modulating insulin action and glucose metabolism in physiological situations, and second, the role of PKR in insulin resistance in obese mice. We used Pkr(-/-) and Pkr(+/+) mice to investigate the role of PKR in modulating insulin sensitivity, glucose metabolism, and insulin signaling in liver, muscle, and adipose tissue in response to a high-fat diet. Our data show that in lean Pkr(-/-) mice, there is an improvement in insulin sensitivity, and in glucose tolerance, and a reduction in fasting blood glucose, probably related to a decrease in protein phosphatase 2A activity and a parallel increase in insulin-induced thymoma viral oncogene-1 (Akt) phosphorylation. PKR is activated in tissues of obese mice and can induce insulin resistance by directly binding to and inducing insulin receptor substrate (IRS)-1 serine307 phosphorylation or indirectly through modulation of c-Jun N-terminal kinase and inhibitor of kappa B kinase beta. Pkr(-/-) mice were protected from high-fat diet-induced insulin resistance and glucose intolerance and showed improved insulin signaling associated with a reduction in c-Jun N-terminal kinase and inhibitor of kappa B kinase beta phosphorylation in insulin-sensitive tissues. PKR may have a role in insulin sensitivity under normal physiological conditions, probably by modulating protein phosphatase 2A activity and serine-threonine kinase phosphorylation, and certainly, this kinase may represent a central mechanism for the integration of pathogen response and innate immunity with insulin action and metabolic pathways that are critical in obesity. (Endocrinology 153:5261-5274, 2012)

Intraspecific competition in Zabrotes subfasciatus: Physiological and behavioral adaptations to different amounts of host

The effects of competition on populations of the bean weevil Zabrotes subfasciatus were analyzed during 41 generations under different competition levels. Three competition environments were established by maintaining the number of couples (6) and varying the amount of available host seeds: HC, high (limited availability of host: 1.35 g); IC, intermediate (intermediate availability of host: 6 g); and LC, low competition (abundance of host: 36 g). It was found that the distribution of the eggs laid on grains was different among treatments: in LC, for example, although females showed high fecundity (35.4 +/- 5.6 eggs/female) the number of eggs laid on each grain was small (1.2 +/- 0.4 eggs on each seed), thus avoiding larval competition of their offspring; whereas in HC treatment, females showed low fecundity (27.04 +/- 4.5 eggs/female) but laid many eggs on each grain (15.03 +/- 4.3 eggs). There were no changes in the ability to respond to different amounts of host via oviposition behavior (egg distribution) during 41 generations. However, HC females had more offspring than LC females under HC conditions. This suggests that HC insects evolved toward higher fitness in crowded conditions. In addition, after inverting the competition level, insects behaved independently of the treatment conditions they experienced through generations, thus showing that oviposition behavior is flexible. Taken together, our results show that Z. subfasciatus presents a broad range of behavioral and physiological responses which allows for quick and reversible adjustments to sudden changes in the amount of resources.

Physiological effects of glyphosate over amino acid profile in conventional and transgenic soybean (Glycine max)

This paper compares the responses of conventional and transgenic soybean to glyphosate application in terms of the contents of 17 detectable soluble amino acids in leaves, analyzed by HPLC and fluorescence detection. Glutamate, histidine, asparagine, arginine + alanine, glycine + threonine and isoleucine increased in conventional soybean leaves when compared to transgenic soybean leaves, whereas for other amino acids, no significant differences were recorded. Univariate analysis allowed us to make an approximate differentiation between conventional and transgenic lines, observing the changes of some variables by glyphosate application. In addition, by means of the multivariate analysis, using principal components analysis (PCA), cluster analysis (CA) and linear discriminant analysis (LDA) it was possible to identify and discriminate different groups based on the soybean genetic origin. (C) 2011 Elsevier Inc. All rights reserved.

PHYSIOLOGICAL CHANGES IN SEEDS AND ANTIOXIDANT METABOLISM OF LETTUCE SEEDLING EXPOSED TO THE ACTION OF Zantedeschia aethiopica Spreng. LEAF EXTRACT

This work aimed to evaluate the influence of different concentrations of Zantedeschia aethiopica Spreng. extract on the physiological performance of the seed and on the response of the antioxidant metabolism of lettuce seedlings. The treatments consisted of leaves extracts from Z. aethiopica at concentrations of 0, 6, 12, 25 and 50%. Germination, first germination count, germination speed and index, length of shoot and radicle, seedling total dry mass, chlorophyll content, activity of superoxide dismutase, catalase and ascorbarte peroxidase enzymes, lipid peroxidation, hydrogen peroxide quantification and seedling emergence, length of organs, and total dry mass of seedlings were evaluated. The percentage of germination, the length of the shoot and radicle of seedlings and the total dry mass of seedlings grown in the greenhouse were reduced as the concentration of the extract increased. There were increases of electrical conductivity, of superoxide dismutase, catalase and ascorbate peroxidadase enzymes and the amount of hydrogen peroxide and lipid peroxidation in seedlings with increasing extract concentration. The extract reduced the physiological quality of lettuce seeds and induced an increased production of hydrogen peroxide in seedlings, which increased the activity of antioxidant enzymes that were not effective in tissue detoxification, resulting in cellular damage and increased numbers of abnormal seedlings.

PHYSIOLOGICAL QUALITY OF OSMOPRIMED EGGPLANT SEEDS

Eggplant seeds germination can be slow and uneven, justifying the use of pre-germinative treatments to improve the performance of seed lots. One option of treatment is the controlled hydration of seeds by priming. In this way, this study aimed to evaluate the performance of eggplant seeds cv. Embu submitted to different methodologies of priming. The seeds used in the experiment were stored in cold chamber (15 degrees C and 55% RH) in paper bags. The research was carried out at Central Laboratory of Seeds/UFLA. The seeds were submitted to the priming in aerated solutions varying the following factors: temperature (15 degrees C and 25 degrees C), time (24, 48 and 72 hours) and solution (water, PEG, KNO3 and PEG+KNO3). Seeds were washed in running water and dried at 30 degrees C, until the return to the initial moisture content, around 10%. The variables analyzed were percentage of germination, percentage of emergence, speed index of emergence and electrical conductivity. The treatments were arranged in a completely randomized design, according to a factorial arrangement 2x3x4+1 (control - seeds without priming). The results showed that priming improves the vigour of eggplant seeds with no effect on viability; the priming in water or KNO3 is efficient to improve the seed vigour and priming in water or KNO3 may use temperature of 15 degrees C or 25 degrees C for 24, 48 or 72 hours.

Physiological responses and rate of perceived exertion in Brazilian jiu-jitsu athletes

In this study, the physiological responses and rate of perceived exertion in Brazilian jiu-jitsu fighters submitted to a combat simulation were investigated. Venous blood samples and heart rate were taken from twelve male Brazilian jiu-jitsu athletes (27.1+/-2.7 yrs, 75.4+/-8.8 kg, 174.9+/-4.4 cm, 9.2+/-2.4% fat), at rest, after a warm-up (ten minutes), immediately after the fight simulation (seven minutes) and after recovery (fourteen minutes). After the combat the rate of perceived exertion was collected. The combat of the Brazilian jiu-jitsu fighters did not change blood concentrations of glucose, triglycerides, total cholesterol, low density lipoprotein and very low density lipoprotein, ureia and ammonia. However, blood levels of high density lipoprotein were significantly higher post-fight (before: 43.0+/-6.9 mg/dL, after: 45.1+/-8.0 mg/dL) and stayed at high levels during the recovery period (43.6+/-8.1 mg/dL) compared to the rest values (40.0+/-6.6 mg/dL). The fight did not cause changes in the concentrations of the cell damage markers of creatine kinase, aspartate aminotransferase and creatinine. However, blood concentrations of the alanine aminotransferase (before: 16.1+/-7.1 U/L, after: 18.6+/-7.1 U/L) and lactate dehydrogenase (before: 491.5+/-177.6 U/L, after: 542.6+/-141.4 U/L) enzymes were elevated after the fight. Heart rate (before: 122+/-25 bpm, after: 165+/-17 bpm) and lactate (before: 2.5+/-1.2 mmol/L, after: 11.9+/-5.8 mmol/L) increased significantly with the completion of combat. Despite this, the athletes rated the fight as being light or somewhat hard (12+/-2). These results showed that muscle glycogen is not the only substrate used in Brazilian jiu-jitsu fights, since there are indications of activation of the glycolytic, lipolytic and proteolytic pathways. Furthermore, the athletes rated the combats as being light or somewhat hard although muscle damage markers were generated.

Pre- and post-puberty physiological plasma oxytocin concentrations in male domestic cats (Felis silvestris catus)

Souza J.O.T., Andriolo A., Franci C.R. & Genaro G. 2012. Pre- and post-puberty physiological plasma oxytocin concentrations in male domestic cats (Felis silvestris catus). Pesquisa Veterinaria Brasileira 32(11):1196-1198. Programa de Pos-Graduacao em Psicobiologia, Faculdade de Filosofia Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo, Cx. Postal 390, Ribeirao Preto, SP 14001-970, Brazil. E-mail: gelsongenaro@hotmail.com The hormone oxytocin is released by the neuropituitary gland through stimulation of the neurons of the supraoptic and paraventricular nuclei of the hypothalamus. In order to determine the physiological concentrations of this hormone in domestic cats, blood samples were collected from 15 male animals (Felis silvestris catus) during the pre- and post-puberty periods (at four and eight months of age, respectively). Oxytocin determination was accomplished by radioimmunoassay. The average oxytocin concentrations measured in the pre- and post-puberty periods were 2.54 +/- 0.24 (mu g/dL) and 2.53 +/- 0.28 (mu g/dL), respectively, and there were no statistical differences between these measurements. Because there are few literature on the analysis of this hormone, especially in the case of male Felis silvestris catus, more studies on the influence of oxytocin on the physiology and reproduction of this species should be conducted under maintenance and situations of stress (such as transportation), and other routine events.

Nuclear abnormalities in erythrocytes and morphometric indexes in the catfish Cathorops spixii (Ariidae) from different sites on the southeastern Brazilian coast

Nuclear abnormalities in erythrocytes (NAE) were taken as biomarkers in the catfish Cathorops spixii (Ariidae) sampled in an estuary little affected by human activity (Cananeia) and in three regions (Santos Channel: SC, Santos Bay: SB and Sao Vicente Channel: SVC) of the Santos-Sao Vicente estuary impacted by various anthropogenic activities. Increases in NAE were observed in fish from SC and SVC sampled in the summer period as compared with specimens from the Cananeia estuary. These results suggest the presence of genotoxic compounds in these regions. However, the absence of significant differences in micronuclei frequency reflects slight mutagenic effects in these individuals. It is possible that the lower NAE frequency in specimens from SB might be associated with the greater remobilization and dilution of chemicals in this region. The low frequency of NAE in C. spixii from the Cananeia estuary is in accordance with the slight anthropogenic influence in this system, and may be suggestive of the absence of genotoxic and mutagenic effects in these organisms.

Anthropometric, physiological, performance, and nutritional profile of the Brazil National Canoe Polo Team

The purpose of this study was to determine the physiological, anthropometric, performance, and nutritional characteristics of the Brazil Canoe Polo National Team. Ten male canoe polo athletes (age 26.7 +/- 4.1 years) performed a battery of tests including assessments of anthropometric parameters, upper-body anaerobic power (Wingate), muscular strength, aerobic power, and nutritional profile. In addition, we characterized heart rate and plasma lactate responses and the temporal pattern of the effort/recovery during a simulated canoe polo match. The main results are as follows: body fat, 12.3 +/- 4.0%; upper-body peak and mean power, 6.8 +/- 0.5 and 4.7 +/- 0.4 W . kg(-1), respectively; 1-RM bench press, 99.1 +/- 11.7 kg; peak oxygen uptake, 44.3 +/- 5.8 mL . kg(-1) . min(-1); total energy intake, 42.8 +/- 8.6 kcal . kg(-1); protein, carbohydrate, and fat intakes, 1.9 +/- 0.1, 5.0 +/- 1.5, and 1.7 +/- 0.4 g . kg(-1), respectively; mean heart rate, 146 +/- 11 beats . min(-1); plasma lactate, 5.7 +/- 3.8 mmol . L-1 at half-time and 4.6 +/- 2.2 mmol . L-1 at the end of the match; effort time (relative to total match time), 93.1 +/- 3.0%; number of sprints, 9.6 +/- 4.4. The results of this study will assist coaches, trainers, and nutritionists in developing more adequate training programmes and dietary interventions for canoe polo athletes.

Diversity and Physiological Characterization of D-Xylose-Fermenting Yeasts Isolated from the Brazilian Amazonian Forest

Background: This study is the first to investigate the Brazilian Amazonian Forest to identify new D-xylose-fermenting yeasts that might potentially be used in the production of ethanol from sugarcane bagasse hemicellulosic hydrolysates. Methodology/Principal Findings: A total of 224 yeast strains were isolated from rotting wood samples collected in two Amazonian forest reserve sites. These samples were cultured in yeast nitrogen base (YNB)-D-xylose or YNB-xylan media. Candida tropicalis, Asterotremella humicola, Candida boidinii and Debaryomyces hansenii were the most frequently isolated yeasts. Among D-xylose-fermenting yeasts, six strains of Spathaspora passalidarum, two of Scheffersomyces stipitis, and representatives of five new species were identified. The new species included Candida amazonensis of the Scheffersomyces clade and Spathaspora sp. 1, Spathaspora sp. 2, Spathaspora sp. 3, and Candida sp. 1 of the Spathaspora clade. In fermentation assays using D-xylose (50 g/L) culture medium, S. passalidarum strains showed the highest ethanol yields (0.31 g/g to 0.37 g/g) and productivities (0.62 g/L.h to 0.75 g/L.h). Candida amazonensis exhibited a virtually complete D-xylose consumption and the highest xylitol yields (0.55 g/g to 0.59 g/g), with concentrations up to 25.2 g/L. The new Spathaspora species produced ethanol and/or xylitol in different concentrations as the main fermentation products. In sugarcane bagasse hemicellulosic fermentation assays, S. stipitis UFMG-XMD-15.2 generated the highest ethanol yield (0.34 g/g) and productivity (0.2 g/L.h), while the new species Spathaspora sp. 1 UFMG-XMD-16.2 and Spathaspora sp. 2 UFMG-XMD-23.2 were very good xylitol producers. Conclusions/Significance: This study demonstrates the promise of using new D-xylose-fermenting yeast strains from the Brazilian Amazonian Forest for ethanol or xylitol production from sugarcane bagasse hemicellulosic hydrolysates.

The use of severity indexes to estimate the risk of death in Intensive Care

The Simplified Acute Physiology Score II (SAPS II) and Logistic Organ Dysfunction System (LODS) are instruments used to classify Intensive Care Unit (ICU) inpatients according to the severity of their condition and risk of death, and evaluate the quality of nursing care. The objective of this study is to evaluate and compare the performance of SAPS II and LODS to predict the mortality of patients admitted to the ICU. The participants were 600 patients from four ICUs located in Sao Paulo, Brazil. Receiver Operator Characteristic (ROC) curves were used to compare the performance of the indexes. Results: The areas under the ROC curves of LODS (0.69) and SAPS II (0.71) indicated moderate discriminatory capacity to identify death or survival. No statistically significant differences were found between these areas (p=0.26). In conclusion, there was equivalence between SAPS II and LODS to estimate the risk of death of ICU patients.

Selection of early-maturing sweet orange cultivars by performance indexes

The objective of this work was to select adequate early-maturing sweet orange cultivars for the fresh fruit market and for industrial processing using performance indexes. Performance indexes for citrus were established from data collected in an experiment carried out in the southwest region of the state of Sao Paulo, involving 12 early-maturing sweet orange cultivars. New results were obtained by identifying cultivars with superior characteristics. In a comparison with 'Hamlin' sweet orange, a standard early-maturing cultivar, 'Valencia 2' and 'Salustiana' were considered better materials for the fresh fruit market, whereas 'Westin' sweet orange was identified as a superior cultivar for orange juice processing.

N-acetylcysteine prevents pulmonary edema and acute kidney injury in rats with sepsis submitted to mechanical ventilation

Campos R, Shimizu MH, Volpini RA, de Bragan a AC, Andrade L, Lopes FD, Olivo C, Canale D, Seguro AC. N-acetylcysteine prevents pulmonary edema and acute kidney injury in rats with sepsis submitted to mechanical ventilation. Am J Physiol Lung Cell Mol Physiol 302: L640-L650, 2012. First published January 20, 2012; doi: 10.1152/ajplung.00097.2011.-Sepsis is a common cause of acute kidney injury (AKI) and acute lung injury. Oxidative stress plays as important role in such injury. The aim of this study was to evaluate the effects that the potent antioxidant N-acetylcysteine (NAC) has on renal and pulmonary function in rats with sepsis. Rats, treated or not with NAC (4.8 g/l in drinking water), underwent cecal ligation and puncture (CLP) 2 days after the initiation of NAC treatment, which was maintained throughout the study. At 24 h post-CLP, renal and pulmonary function were studied in four groups: control, control + NAC, CLP, and CLP + NAC. All animals were submitted to low-tidal-volume mechanical ventilation. We evaluated respiratory mechanics, the sodium cotransporters Na-K-2Cl (NKCC1) and the alpha-subunit of the epithelial sodium channel (alpha-ENaC), polymorphonuclear neutrophils, the edema index, oxidative stress (plasma thiobarbituric acid reactive substances and lung tissue 8-isoprostane), and glomerular filtration rate. The CLP rats developed AKI, which was ameliorated in the CLP + NAC rats. Sepsis-induced alterations in respiratory mechanics were also ameliorated by NAC. Edema indexes were lower in the CLP + NAC group, as was the wet-to-dry lung weight ratio. In CLP + NAC rats, alpha-ENaC expression was upregulated, whereas that of NKCC1 was downregulated, although the difference was not significant. In the CLP + NAC group, oxidative stress was significantly lower and survival rates were significantly higher than in the CLP group. The protective effects of NAC (against kidney and lung injury) are likely attributable to the decrease in oxidative stress, suggesting that NAC can be useful in the treatment of sepsis.