Characterization of KPC-Producing Serratia marcescens in an Intensive Care Unit of a Brazilian Tertiary Hospital.

Serratia marcescens has emerged as an important opportunistic pathogen responsible for nosocomial and severe infections. Here, we determined phenotypic and molecular characteristics of 54 S. marcescens isolates obtained from patient samples from intensive-care-unit (ICU) and neonatal intensive-care-unit (NIUC) of a Brazilian tertiary hospital. All isolates were resistant to beta-lactam group antibiotics, and 92.6% (50/54) were not susceptible to tigecycline. Furthermore, 96.3% showed intrinsic resistance to polymyxin E (colistin), a last-resort antibiotic for the treatment of infections caused by MDR (multidrug-resistant) Gram-negative bacteria. In contrast, high susceptibility to other antibiotics such as fluoroquinolones (81.5%), and to aminoglycosides (as gentamicin 81.5%, and amikacin 85.2%) was found. Of all isolates, 24.1% were classified as MDR. The presence of resistance and virulence genes were examined by PCR and sequencing. All isolates carried KPC-carbapenemase (bla KPC ) and extended spectrum beta-lactamase bla TEM genes, 14.8% carried bla OXA- 1, and 16.7% carried bla CTX-M- 1 group genes, suggesting that bacterial resistance to ß-lactam antibiotics found may be associated with these genes. The genes SdeB/HasF and SdeY/HasF that are associated with efflux pump mediated drug extrusion to fluoroquinolones and tigecycline, respectively, were found in 88.9%. The aac(6')-Ib-cr variant gene that can simultaneously induce resistance to aminoglycoside and fluoroquinolone was present in 24.1% of the isolates. Notably, the virulence genes to (i) pore-forming toxin (ShlA); (ii) phospholipase with hemolytic and cytolytic activities (PhlA); (iii) flagellar transcriptional regulator (FlhD); and (iv) positive regulator of prodigiosin and serratamolide production (PigP) were present in 98.2%. The genetic relationship among the isolates determined by ERIC-PCR demonstrated that the vast majority of isolates were grouped in a single cluster with 86.4% genetic similarity. In addition, many isolates showed 100% genetic similarity to each other, suggesting that the S. marcescens that circulate in this ICU are closely related. Our results suggest that the antimicrobial resistance to many drugs currently used to treat ICU and NIUC patients, associated with the high frequency of resistance and virulence genes is a worrisome phenomenon. Our findings emphasize the importance of active surveillance plans for infection control and to prevent dissemination of these strains.

High Prevalence of Multidrug-Resistant Klebsiella pneumoniae Harboring Several Virulence and ß-Lactamase Encoding Genes in a Brazilian Intensive Care Unit.

Klebsiella pneumoniae is an important opportunistic pathogen that commonly causes nosocomial infections and contributes to substantial morbidity and mortality. We sought to investigate the antibiotic resistance profile, pathogenic potential and the clonal relationships between K. pneumoniae (n = 25) isolated from patients and sources at a tertiary care hospital's intensive care units (ICUs) in the northern region of Brazil. Most of K. pneumoniae isolates (n = 21, 84%) were classified as multidrug resistant (MDR) with high-level resistance to ß-lactams, aminoglycosides, quinolones, tigecycline, and colistin. All the 25 isolates presented extended-spectrum beta-lactamase-producing (ESBL), including carbapenemase producers, and carried the bla KPC (100%), bla TEM (100%), bla SHV variants (n = 24, 96%), bla OXA-1 group (n = 21, 84%) and bla CTX-M-1 group (n = 18, 72%) genes. The K2 serotype was found in 4% (n = 1) of the isolates, and the K1 was not detected. The virulence-associated genes found among the 25 isolates were mrkD (n = 24, 96%), fimH-1 (n = 22, 88%), entB (100%), iutA (n = 10, 40%), ybtS (n = 15, 60%). The genes related with efflux pumps and outer membrane porins found were AcrAB (100%), tolC (n = 24, 96%), mdtK (n = 22, 88%), OmpK35 (n = 15, 60%), and OmpK36 (n = 7, 28%). ERIC-PCR was employed to determine the clonal relationship between the different isolated strains. The obtained ERIC-PCR patterns revealed that the similarity between isolates was above 70%. To determine the sequence types (STs) a multilocus sequence typing (MLST) assay was used. The results indicated the presence of high-risk international clones among the isolates. In our study, the wide variety of MDR K. pneumoniae harboring ß-lactams and virulence genes strongly suggest a necessity for the implementation of effective strategies to prevent and control the spread of antibiotic resistant infections.

Supplementation of cow milk naturally enriched in polyunsaturated fatty acids and polyphenols to growing rats.

This study investigated whether intake of cow milk, naturally enriched with polyunsaturated fatty acids (PUFA, omega-3) and polyphenols (from propolis extract and vitamin E), from manipulation of cow's diet, would result in positive metabolic effects in rats from weaning until adulthood. Male Wistar rats were fed a standard chow diet or a hypercaloric diet (metabolically disturbed rats, obese) which was supplemented with either whole common milk, milk enriched with PUFA (PUFA-M) or milk enriched with PUFA and polyphenols (PUFA/P-M), at 5mL/kg body weight,having water as control. Whole milk supplementation increased initial weight gain and reduced gain in the adulthood of rats. Intake of common milk reduced cholesterol levels in non-obese rats and reduced insulin resistance in obese rats. PUFA-milk showed a decreasing effect on plasma triacylglycerol and VLDL concentrations, increasing plasma HDL concentration and reducing adipocyte size of non-obese rats, but no effect was observed in obese rats. PUFA/P-milk in obese rats resulted in greater deposition of muscle mass and mesenteric fat, with a tendency to lower LDL levels, and resulted a visceral fat accumulation in non-obese rats. Thus, whole common milk and PUFA-rich milk have shown to be beneficial in a normal metabolic condition, whereas common milk and milk enriched with PUFA and polyphenols improve metabolic effects of obesity.

Immediate and residual effects of low-dose nandrolone decanoate and treadmill training on adipose and reproductive tissues of male Wistar rats.

CONTEXT: Residual effects after nandrolone decanoate (ND) treatment are not reported. OBJECTIVE: Immediate and residual effects of low-dose ND and treadmill training were investigated. MATERIALS AND METHODS: Male rats were trained and/or ND-treated for four weeks and the assessments were made after this period or four weeks later. RESULTS: The groups did not differ in final plasma glucose or AUC of the ivGTT, but hyperinsulinemia was noticed in some trained/treated groups. Training with ND increased muscle mass and ND decreased the reproductive structures. Decreased fat with training was reversed by detraining. DISCUSSION: The anabolic action of ND on skeletal muscle was enhanced by training. Fat and lipid changes were more linked to training/detraining, but the effects of ND on the reproductive structures persisted after treatment. CONCLUSIONS: The effects of training on fat and muscle were not maintained after detraining, but low-dose ND had persistent effects on the reproductive structures.

Autoeficácia na solução de problemas matemáticos e variáveis relacionadas / Self-efficacy in mathematics problem solving and related variables / Auto-eficacia en la resolución de problemas matemáticos y variables asociadas

Baseado na Teoria Social Cognitiva de Albert Bandura, o presente estudo teve como objetivo verificar a existência de relações entre as crenças de autoeficácia e o desempenho na solução de problemas matemáticos. Buscou-se também analisar as correlações entre os instrumentos e avaliar o autoconceito matemático e a autoeficácia para a aprendizagem autorregulada, além de outra variáveis pertinentes. Os participantes foram 131 estudantes da quinta série do período matutino, sendo 72 do gênero masculino e 59 do gênero feminino, matriculados em uma escola confessional privada de uma cidade de grande porte da região sudeste do país. A coleta de dados foi conduzida em período normal de aula e incluiu a aplicação dos seguintes instrumentos: escala autoeficácia para aprendizagem autorregulada, escala de autoconceito, escala de autoeficácia matemática, escala de importância da Matemática, e um instrumento de autoeficácia matemática. A análise dos resultados apontou que tanto a autoeficácia matemática, quanto a autoeficácia para autorregulação estavam relacionadas ao desempenho na tarefa de solução de problemas. Estes dados trazem implicações ao processo de ensino-aprendizagem de Matemática que deve compreender, além do desenvolvimento de habilidades, a construção de autopercepções favoráveis do estudante.

Based on Albert Bandura' Social Cognitive Theory the objective of the present study was to verify the existence of relations between self-efficacy beliefs and performance in mathematical problem solving. It also sought to evaluate the mathematical self-concept and self-efficacy for self-regulated learning. We attempted to study the correlation between the instruments and evaluate the mathematical self-concept and self-efficacy for self-regulated learning, and other relevant variables. Participants were 131 fifth graders, 72 males and 59 females from in a private religious school in a large city in the southeast of the country. Data have been collected in regular class schedules and included the following instruments: self-efficacy scale for regulated learning, self-concept-scale, importance of mathematics, and mathematics self-efficacy instruments 1 and 2. Results revealed that both mathematics self-efficacy, and self-efficacy for self-regulated learning were related to performance on solving problems. These data have implications for the process of teaching and learning of mathematics which shall include, in addition to developing abilities, building students' suitable self-perceptions.

Fundamentado en la teoría social cognitiva de Albert Bandura, el presente investigó la existencia de relaciones entre las creencias de auto-eficacia y el rendimiento en la solución de problemas matemáticos. Hemos tratado de estudiar la correlación entre los instrumentos y evaluar el auto-concepto matemático, la auto-eficacia para el aprendizaje auto-regulado, y otras variables pertinentes. Los participantes fueron 131 estudiantes de quinto grado del período de la mañana, 72 varones y 59 mujeres inscritos en una escuela religiosa privada en una gran ciudad en el sureste del país. La colecta de datos se llevó a cabo en la clase normal y estén incluidos los siguientes instrumentos: escala de auto-eficacia para el aprendizaje autorregulado, escala de auto-concepto, escala de la importancia de las matemáticas, y un instrumento de auto-eficacia matemática. Los resultados mostraron que tanto la auto-eficacia matemática y auto-eficacia de la autorregulación se relacionam con el rendimiento en la tarea de resolver los problemas. Estos datos tienen implicaciones para el proceso de enseñanza y aprendizaje de las matemáticas, que incluirá, además de desarrollar habilidades, la construcción de auto-percepción a favor del estudiante.

Autoeficácia na solução de problemas matemáticos e variáveis relacionadas / Self-efficacy in mathematics problem solving and related variables / Auto-eficacia en la resolución de problemas matemáticos y variables asociadas

Baseado na Teoria Social Cognitiva de Albert Bandura, o presente estudo teve como objetivo verificar a existência de relações entre as crenças de autoeficácia e o desempenho na solução de problemas matemáticos. Buscou-se também analisar as correlações entre os instrumentos e avaliar o autoconceito matemático e a autoeficácia para a aprendizagem autorregulada, além de outra variáveis pertinentes. Os participantes foram 131 estudantes da quinta série do período matutino, sendo 72 do gênero masculino e 59 do gênero feminino, matriculados em uma escola confessional privada de uma cidade de grande porte da região sudeste do país. A coleta de dados foi conduzida em período normal de aula e incluiu a aplicação dos seguintes instrumentos: escala autoeficácia para aprendizagem autorregulada, escala de autoconceito, escala de autoeficácia matemática, escala de importância da Matemática, e um instrumento de autoeficácia matemática. A análise dos resultados apontou que tanto a autoeficácia matemática, quanto a autoeficácia para autorregulação estavam relacionadas ao desempenho na tarefa de solução de problemas. Estes dados trazem implicações ao processo de ensino-aprendizagem de Matemática que deve compreender, além do desenvolvimento de habilidades, a construção de autopercepções favoráveis do estudante.(AU).

Based on Albert Bandura' Social Cognitive Theory the objective of the present study was to verify the existence of relations between self-efficacy beliefs and performance in mathematical problem solving. It also sought to evaluate the mathematical self-concept and self-efficacy for self-regulated learning. We attempted to study the correlation between the instruments and evaluate the mathematical self-concept and self-efficacy for self-regulated learning, and other relevant variables. Participants were 131 fifth graders, 72 males and 59 females from in a private religious school in a large city in the southeast of the country. Data have been collected in regular class schedules and included the following instruments: self-efficacy scale for regulated learning, self-concept-scale, importance of mathematics, and mathematics self-efficacy instruments 1 and 2. Results revealed that both mathematics self-efficacy, and self-efficacy for self-regulated learning were related to performance on solving problems. These data have implications for the process of teaching and learning of mathematics which shall include, in addition to developing abilities, building students' suitable self-perceptions.(AU).

Fundamentado en la teoría social cognitiva de Albert Bandura, el presente investigó la existencia de relaciones entre las creencias de auto-eficacia y el rendimiento en la solución de problemas matemáticos. Hemos tratado de estudiar la correlación entre los instrumentos y evaluar el auto-concepto matemático, la auto-eficacia para el aprendizaje auto-regulado, y otras variables pertinentes. Los participantes fueron 131 estudiantes de quinto grado del período de la mañana, 72 varones y 59 mujeres inscritos en una escuela religiosa privada en una gran ciudad en el sureste del país. La colecta de datos se llevó a cabo en la clase normal y estén incluidos los siguientes instrumentos: escala de auto-eficacia para el aprendizaje autorregulado, escala de auto-concepto, escala de la importancia de las matemáticas, y un instrumento de auto-eficacia matemática. Los resultados mostraron que tanto la auto-eficacia matemática y auto-eficacia de la autorregulación se relacionam con el rendimiento en la tarea de resolver los problemas. Estos datos tienen implicaciones para el proceso de enseñanza y aprendizaje de las matemáticas, que incluirá, además de desarrollar habilidades, la construcción de auto-percepción a favor del estudiante.(AU).

Role of oxytocin in energy metabolism.

The basic mechanisms that lead obesity are not fully understood; however, several peptides undoubtedly play a role in regulating body weight. Obesity, a highly complex metabolic disorder, involves central mechanisms that control food intake and energy expenditure. Previous studies have shown that central or peripheral oxytocin administration induces anorexia. Recently, in an apparent discrepancy, rodents that were deficient in oxytocin or the oxytocin receptor were shown to develop late-onset obesity without changing their total food intake, which indicates the physiological importance of oxytocin to body metabolism. Oxytocin is synthesized not only within magnocellular and parvocellular neurons but also in several organs, including the ovary, uterus, placenta, testis, thymus, kidney, heart, blood vessels, and skin. The presence of oxytocin receptors in neurons, the myometrium and myoepithelial cells is well recognized; however, this receptor has also been identified in other tissues, including the pancreas and adipose tissue. The oxytocin receptor is a typical class I G protein-coupled receptor that is primarily linked to phospholipase C-ß via Gq proteins but can also be coupled to other G proteins, leading to different functional effects. In this review, we summarize the present knowledge of the effects of oxytocin on controlling energy metabolism, focusing primarily on the role of oxytocin on appetite regulation, thermoregulation, and metabolic homeostasis.

Cimicifuga racemosa impairs fatty acid ß-oxidation and induces oxidative stress in livers of ovariectomized rats with renovascular hypertension.

The aim of this work was to evaluate the effects of therapeutic doses of Cimicifuga racemosa on cardiovascular parameters and on liver lipid metabolism and redox status in an animal model of estrogen deficiency associated with hypertension, a condition that could make the liver more vulnerable to drug-induced injuries. Female Wistar rats were subjected to the surgical procedures of bilateral ovariectomy (OVX) and induction of renovascular hypertension (two-kidneys, one-clip; 2K1C). These animals (OVX + 2K1C) were treated with daily doses of a C. racemosa extract, using a dose that is similar to that recommended to postmenopausal women (0.6 mg/kg), over a period of 15 days. The results were compared to those of untreated OVX + 2K1C, OVX, and control rats. The treatment with C. racemosa caused a significant reduction in blood pressure. In the liver, treatment did not prevent the development of steatosis, and it reduced the mitochondrial and peroxisomal capacity to oxidize octanoyl-CoA compared to the untreated animals. In addition, C. racemosa caused numerous undesirable effects on the liver redox status: it increased the mitochondrial reactive oxygen species generation, an event that was not accompanied by an increase in the activity of superoxide dismutase, and it induced a decrease in peroxisomal catalase activity. Although the reduced glutathione content had not been affected, a phenomenon that probably reflected the restoration of glucose-6-phosphate dehydrogenase activity by C. racemosa, oxidative damage was evidenced by the elevated level of thiobarbituric acid-reactive substances found in the liver of treated animals.

Atitudes de professores e futuros professores em relação à Matemática / Attitudes of teachers and future teachers towards Mathematics

O estudo compara a existência e a direção da atitude em relação à Matemática de quatro grupos amostrais: estudantes de licenciatura em matemática em dois momentos de sua formação, e professores de matemática em dois momentos de exercício profissional. Os dados foram obtidos de participantes voluntários (N = 440), por meio de escala de atitude, texto autobiográfico, questionário e entrevista semi-estruturada. A análise estatística dos dados permitiu constatar diferenças na medida de atitudes em relação à Matemática entre os grupos amostrais, sendo significativa a presença de atitude favorável de alunos do início da licenciatura em comparação à de professores em exercício. Essas diferenças foram corroboradas por traços característicos dos tipos de atitude, identificados por análise qualitativa. A mudança de atitude em relação à Matemática pode ser explicada pelas particularidades das diferentes circunstâncias da vida estudantil e profissional. Recomendações para a formação docente em Matemática são sugeridas.

This study compares the existence and direction of attitude towards Mathematics shown by four sample groups composed of students enrolled at Mathematics teachers' College in two moments of their training courses, and Mathematics teachers in two moments of their professional life. Data were obtained from volunteer participants (N = 440), by means of an attitude scale, an autobiographical text, a questionnaire and a semi-structured interview. The statistical analysis show differences in attitude measurements concerning Mathematics among the sample groups, with a significant presence of favorable attitude in students at the beginning of College when compared to attitudes of practicing teachers. These differences were corroborated by the characteristic traits of attitude types, identified by a qualitative analysis. The attitude change toward Mathematics can be explained by the peculiarities of the different circumstances on the students' and the teachers' lives. Recommendations for teaching training in Mathematics are pointed out.

Atitudes de professores e futuros professores em relação à Matemática / Attitudes of teachers and future teachers towards Mathematics

O estudo compara a existência e a direção da atitude em relação à Matemática de quatro grupos amostrais: estudantes de licenciatura em matemática em dois momentos de sua formação, e professores de matemática em dois momentos de exercício profissional. Os dados foram obtidos de participantes voluntários (N = 440), por meio de escala de atitude, texto autobiográfico, questionário e entrevista semi-estruturada. A análise estatística dos dados permitiu constatar diferenças na medida de atitudes em relação à Matemática entre os grupos amostrais, sendo significativa a presença de atitude favorável de alunos do início da licenciatura em comparação à de professores em exercício. Essas diferenças foram corroboradas por traços característicos dos tipos de atitude, identificados por análise qualitativa. A mudança de atitude em relação à Matemática pode ser explicada pelas particularidades das diferentes circunstâncias da vida estudantil e profissional. Recomendações para a formação docente em Matemática são sugeridas.(AU)

This study compares the existence and direction of attitude towards Mathematics shown by four sample groups composed of students enrolled at Mathematics teachers' College in two moments of their training courses, and Mathematics teachers in two moments of their professional life. Data were obtained from volunteer participants (N = 440), by means of an attitude scale, an autobiographical text, a questionnaire and a semi-structured interview. The statistical analysis show differences in attitude measurements concerning Mathematics among the sample groups, with a significant presence of favorable attitude in students at the beginning of College when compared to attitudes of practicing teachers. These differences were corroborated by the characteristic traits of attitude types, identified by a qualitative analysis. The attitude change toward Mathematics can be explained by the peculiarities of the different circumstances on the students' and the teachers' lives. Recommendations for teaching training in Mathematics are pointed out.(AU)

Energetic responses to cold temperatures in rats lacking forebrain-caudal brain stem connections.

Hypothalamic neurons are regarded as essential for integrating thermal afferent information from skin and core and issuing commands to autonomic and behavioral effectors that maintain core temperature (T(c)) during cold exposure and for the control of energy expenditure more generally. Caudal brain stem neurons are necessary elements of the hypothalamic effector pathway and also are directly driven by skin and brain cooling. To assess whether caudal brain stem processing of thermal afferent signals is sufficient to drive endemic effectors for thermogenesis, heart rate (HR), T(c), and activity responses of chronic decerebrate (CD) and control rats adapted to 23 degrees C were compared during cold exposure (4, 8, or 12 degrees C) for 6 h. Other CDs and controls were exposed to 4 or 23 degrees C for 2 h, and tissues were processed for norepinephrine turnover (NETO), a neurochemical measure of sympathetic drive. Controls maintained T(c) for all temperatures. CDs maintained T(c) for the 8 and 12 degrees C exposures, but T(c) declined 2 degrees C during the 4 degrees C exposure. Cold exposure elevated HR in CDs and controls alike. Tachycardia magnitude correlated with decreases in environmental temperature for controls, but not CDs. Cold increased NETO in brown adipose tissue, heart, and some white adipose tissue pads in CDs and controls compared with their respective room temperature controls. These data demonstrate that, in neural isolation from the hypothalamus, cold exposure drives caudal brain stem neuronal activity and engages local effectors that trigger sympathetic energetic and cardiac responses that are comparable in many, but not in all, respects to those seen in neurologically intact rats.

Crenças de auto-eficácia, autoconceito e desempenho em matemática / Self-efficacy beliefs, self-concept and performance in mathematics

Este trabalho teve como objetivo investigar as relações entre o autoconceito, as crenças de auto-eficácia e o desempenho em Matemática de alunos das séries iniciais do Ensino Fundamental. Participaram do estudo 122 estudantes de terceira e quarta séries, de ambos os gêneros, com idade variando de oito a treze anos, matriculados em uma escola pública estadual de um município do interior de São Paulo. Os dados foram coletados por meio de um questionário de auto-eficácia matemática, uma escala de autoconceito matemático e uma prova de matemática. Para se verificar correlações entre as variáveis, foi efetuada a matriz de correlação de Pearson. A análise dos resultados mostrou que o desempenho dos alunos encontrava-se positivamente relacionado ao autoconceito e à auto-eficácia matemática. Além disso, pôde-se evidenciar uma relação positiva e significativa entre tais constructos. De forma geral, os resultados deste estudo confirmaram dados de outros sobre a mesma temática, bem como as formulações teóricas da perspectiva sócio-cognitiva.

The objective of the present study was to investigate the relationship between involving self-efficacy beliefs, self-concept and performance in mathematics amongst early elementary school students. The subjects comprised 122 third and fourth graders, both male and female, whose ages varied from eight to thirteen, attending a state public school in an inner city in the state of São Paulo. Data were collected using a mathematical self-efficacy questionnaire, a mathematical self-concept scale, and a mathematics test. To investigate correlations among variables, a Pearson correlation test was conducted. The results indicated that student performance was positively related to self-concept and mathematical self-efficacy. In addition, a significant, positive relationship could be seen between the beliefs of mathematical self-concept and mathematical self-efficacy. The results of the present study, in general terms, bear out other research data on the same theme, as well as theoretical assumptions from a socio-cognitive perspective.

Crenças de auto-eficácia, autoconceito e desempenho em matemática / Self-efficacy beliefs, self-concept and performance in mathematics

Este trabalho teve como objetivo investigar as relações entre o autoconceito, as crenças de auto-eficácia e o desempenho em Matemática de alunos das séries iniciais do Ensino Fundamental. Participaram do estudo 122 estudantes de terceira e quarta séries, de ambos os gêneros, com idade variando de oito a treze anos, matriculados em uma escola pública estadual de um município do interior de São Paulo. Os dados foram coletados por meio de um questionário de auto-eficácia matemática, uma escala de autoconceito matemático e uma prova de matemática. Para se verificar correlações entre as variáveis, foi efetuada a matriz de correlação de Pearson. A análise dos resultados mostrou que o desempenho dos alunos encontrava-se positivamente relacionado ao autoconceito e à auto-eficácia matemática. Além disso, pôde-se evidenciar uma relação positiva e significativa entre tais constructos. De forma geral, os resultados deste estudo confirmaram dados de outros sobre a mesma temática, bem como as formulações teóricas da perspectiva sócio-cognitiva.(AU)

The objective of the present study was to investigate the relationship between involving self-efficacy beliefs, self-concept and performance in mathematics amongst early elementary school students. The subjects comprised 122 third and fourth graders, both male and female, whose ages varied from eight to thirteen, attending a state public school in an inner city in the state of São Paulo. Data were collected using a mathematical self-efficacy questionnaire, a mathematical self-concept scale, and a mathematics test. To investigate correlations among variables, a Pearson correlation test was conducted. The results indicated that student performance was positively related to self-concept and mathematical self-efficacy. In addition, a significant, positive relationship could be seen between the beliefs of mathematical self-concept and mathematical self-efficacy. The results of the present study, in general terms, bear out other research data on the same theme, as well as theoretical assumptions from a socio-cognitive perspective.(AU)

Differential sympathetic drive to adipose tissues after food deprivation, cold exposure or glucoprivation.

Surplus energy is principally stored in white adipose tissue (WAT) as triacylglycerol and mobilized via lipolysis through norepinephrine (NE) released from sympathetic nervous system terminals innervating WAT. We demonstrated that central melanocortin receptor agonism provokes differential sympathetic drives across WAT pads and interscapular brown adipose tissue (IBAT). Here we tested for differential WAT and IBAT sympathetic drive to known lipolytic stimuli {glucoprivation [2-deoxy-D-glucose (2-DG)], cold exposure (5 degrees C), food deprivation (16 h), or both cold exposure and food deprivation} by measuring NE turnover (NETO). Only inguinal WAT NETO significantly increased across all stimuli. Dorsal subcutaneous WAT NETO only increased with glucoprivation. Retroperitoneal WAT NETO increased with glucoprivation, cold and cold + food deprivation, but not by food deprivation. Epididymal WAT NETO was unaffected by glucoprivation but increased with cold, cold + food deprivation or food deprivation, but to a small significant degree. IBAT NETO was unaffected by glucoprivation or food deprivation, but increased with cold and cold + food deprivation. Plasma glucose decreased with food deprivation and increased with 2-DG administration or cold exposure. Plasma glycerol was increased with food deprivation, cold, and their combination but not with 2-DG, whereas plasma free fatty acids increased with food deprivation, cold + food deprivation, and 2-DG. These data show differential sympathetic drive to WAT and BAT for four different lipolytic stimuli, exemplifying the fat pad-specific pattern of WAT sympathetic drive across lipid-mobilizing conditions and emphasizing the need to analyze multiple adipose depots for measures of NETO and likely most measures.

Peroxisome proliferator-activated receptor-gamma-mediated positive energy balance in the rat is associated with reduced sympathetic drive to adipose tissues and thyroid status.

Peroxisome proliferator-activated receptor-gamma (PPARgamma) activation up-regulates thermogenesis-related genes in rodent white and brown adipose tissues (WAT and BAT) without increasing whole-body energy expenditure. We tested here whether such dissociation is the result of a negative modulation of sympathetic activity to WAT and BAT and thyroid axis components by PPARgamma activation. Administration of the PPARgamma agonist rosiglitazone (15 mg/kg.d) for 7 d to male Sprague Dawley rats increased food intake (10%), feed efficiency (31%), weight gain (45%), spontaneous motor activity (60%), and BAT and WAT mass and reduced whole-body oxygen consumption. Consistent with an anabolic setting, rosiglitazone markedly reduced sympathetic activity to BAT and WAT (>50%) and thyroid status as evidenced by reduced levels of plasma thyroid hormones (T(4) and T(3)) and mRNA levels of BAT and liver T(3)-generating enzymes iodothyronine type 2 (-40%) and type 1 (-32%) deiodinases, respectively. Rosiglitazone also decreased mRNA levels of the thyroid hormone receptor (THR) isoforms alpha1 (-34%) and beta (-66%) in BAT and isoforms alpha1 (-20%) and alpha2 (-47%) in retroperitoneal WAT. These metabolic effects were associated with a reduction in mRNA levels of the pro-energy expenditure peptides CRH and CART in specific hypothalamic nuclei. A direct central action of rosiglitazone is, however, unlikely based on its low brain uptake and lack of metabolic effects of intracerebroventricular administration. In conclusion, a reduction in BAT sympathetic activity and thyroid status appears to, at least partly, explain the PPARgamma-induced reduction in energy expenditure and the fact that up-regulation of thermogenic gene expression does not translate into functional stimulation of whole-body thermogenesis in vivo.

Relações entre a percepção da estrutura de um problema, a memória e a memória matemática / Relations among mathematical memory, memory and perception of a problem structure

Este estudo partiu do pressuposto que, ao solucionar um problema matemático, o indivíduo, inicialmente, percebe seus elementos componentes, analítica e sinteticamente, isolando-os, estabelecendo hierarquia, combinações e relações entre eles. Considerando algumas relações teóricas entre a percepção da estrutura de um problema, a memória e a memória matemática, buscou-se estudar tais relações empiricamente. Trinta e dois sujeitos foram selecionados dentre 177 estudantes de quinta e oitava séries do Ensino Fundamental e terceira série do Ensino Médio, mediante o desempenho em uma prova matemática e uma prova para avaliar a memória matemática. Esses sujeitos foram submetidos ao teste das figuras complexas de Rey. Por meio de análise de correlação, foi obtido coeficiente de Pearson 0,54 entre os desempenhos na prova para avaliar a memória matemática e o teste de reprodução das figuras complexas. A análise qualitativa das relações entre os resultados obtidos por dois sujeitos mostrou que um deles, tendo percebido os elementos do mais geral aos mais específicos, tanto nos problemas matemáticos, como na figura complexa, teve maior facilidade em representá-los, retê-los e recuperá-los. O outro sujeito, entretanto, percebia na figura elementos justapostos sem que fosse estabelecida relação entre eles. Essa dificuldade de percepção e recuperação também foi observada na prova para avaliar a memória matemática.(AU)

This study assumed that during a mathematical problem solving the person, at the beginning, perceive synthetically and analytically their elements. The analytic perception is characterized by the problem elements isolate, differentiate accessing and hierarchy establishing. The synthetic perception happens during relations and combinations establishing between problem elements by the person. Considering the theoretical relations between mathematical memory, memory and perception, this research aimed to study this relationship empirically. For that, 32 students were selected among 177 students from basic education, considering their performance in a mathematics test and a mathematical memory test. These students were submitted to the reproduction and copy test of Rey complex figures. Through correlation analysis it was obtained the Pearson coefficient 0,54 between reproduction complex figures test and mathematical memory test performance. The qualitative analysis of relations between individual results in complex figures test and the performance in mathematical memory test showed that when a person perceives the elements from the general toward specific, either in mathematical problems or in complex figures, the person recovered, retrieved and represented it easily. Otherwise, when the person perceived juxtaposed elements in the figure, without relations establishing, this retrieving and perception difficulty was observed also in mathematical memory test.(AU)

Fat storage is partially dependent on vagal activity and insulin secretion of hypothalamic obese rat.

Hypothalamic MSG-obese rats show hyperinsulinemia and tissue insulin resistance, and they display intense parasympathetic activity. Current analysis investigates whether early subdiaphragmatic vagotomy prevents tissue insulin sensitivity impairment in adult obese MSG-rats. Hypothalamic obesity was induced by MSG (4 mg/g BW), daily, from birth up to 5 days. Control animals receiving saline solution. On the 30th day rats underwent bilateral subdiaphragmatic vagotomy or sham surgery. An intravenous glucose tolerance test (i.v.GTT) was performed when rats turned 90 days old. Total white fat tissue (WAT) from rat carcass was extracted and isolated; the interscapular brown fat tissue (IBAT) was weighed. Rather than blocking obesity, vagotomy reduced WAT and IBAT in MSG-obese rats when the latter were compared to sham MSG-rats. High blood fasting insulin and normal glucose levels were also observed in MSG-obese rats. Although glucose intolerance, high insulin secretion, and significant insulin resistance were recorded, vagotomy improved fasting insulinemia, glucose tolerance and insulin tissue sensitivity in MSG-obese rats. Results suggest that increased fat accumulation is caused, at least in part, by high blood insulin concentration, and enhanced parasympathetic activity on MSG-obese rats.

Differential activation of the sympathetic innervation of adipose tissues by melanocortin receptor stimulation.

Melanocortins are implicated in the control of energy intake/expenditure. Centrally administered melanotan II (MTII), a synthetic melanocortin 3/4-receptor agonist, decreases adiposity beyond that accountable by food intake decreases. Melanocortin-4 receptor (MC4-R) mRNA is expressed on sympathetic nervous system (SNS) outflow neurons to white adipose tissue (WAT) in Siberian hamsters, suggesting a role in lipid mobilization. Therefore, we tested whether third ventricular injections of MTII increased sympathetic drive to WAT and interscapular brown adipose tissue (IBAT) using norepinephrine turnover (NETO) as a measure of sympathetic drive. We also tested for MTII-induced changes in lipolysis-related WAT gene expression (beta3-adrenoceptors, hormone sensitive lipase) and IBAT thermogenesis (beta3-adrenoceptor, uncoupling protein-1). Finally, we tested whether third ventricularly injected MTII, a highly selective MC4-R agonist (cyclo[beta-Ala-His-D-Phe-Arg-Trp-Glu]NH2) increased or agouti-related protein decreased IBAT temperature in hamsters implanted with sc IBAT temperature transponders. Centrally administered MTII provoked differential sympathetic drives to WAT and IBAT (increased inguinal WAT, dorsosubcutaneous WAT and IBAT NETO, but not epididymal WAT and retroperitoneal WAT NETO). MTII also increased circulating concentrations of the lipolytic products free fatty acids and glycerol but not plasma catecholamines, suggesting lipid mobilization via WAT SNS innervation and not via adrenal medullary catecholamines. WAT or IBAT gene expression was largely unaffected by acute MTII treatment, but IBAT temperature was increased by MTII and the MC4-R agonist and decreased by agouti-related protein. Collectively, this is the first demonstration of central melanocortin agonist stimulation of WAT lipolysis through the SNS and confirms melanocortin-induced changes in BAT thermogenesis.

Atitudes em relação à estatística e à matemática / Attitudes toward statistics and toward mathematics

O objetivo deste trabalho foi verificar se as atitudes em relação à estatística poderiam estar relacionadas às atitudes em relação à matemática desenvolvidas durante a trajetória escolar do estudante. Os sujeitos foram 330 alunos de graduação que cursavam estatística introdutória em 1998. Foi aplicado um questionário, uma escala de atitudes em relação à estatística e outra em relação à matemática. As duas escalas apresentaram altos coeficientes de consistência interna. Verificou-se que os alunos apresentaram atitudes mais positivas em relação à matemática do que em relação à estatística. Não foram encontradas diferenças por gênero nas pontuações das duas escalas. Os alunos de exatas apresentaram atitudes mais positivas em relação à matemática e os de humanas atitudes mais negativas em relação à estatística. Os resultados indicaram que existe uma associação das atitudes em relação à matemática na formação das atitudes em relação à estatística e que essa associação é mais forte para os alunos de humanas.