Consumo de bens duráveis e poupança em uma nova trajetória de comportamento do consumidor brasileiro

O trabalho avalia a dinâmica descrita pelo consumo de bens duráveis e poupança dos consumidores brasileiros entre setembro de 2005 e abril de 2011 e contribui com a literatura ao utilizar como ferramenta de análise um modelo autoregressivo com valor limite endógeno e dados qualitativos da pesquisa Sondagem de Expectativas do Consumidor Brasileiro, da FGV. Indicadores qualitativos para essas duas variáveis foram calculados e a metodologia proposta permitiu investigar, simultaneamente, a linearidade e estacionaridade de suas trajetórias. Os resultados sugerem, em ambos os casos, uma dinâmica não-linear com raiz unitária parcial. Adicionalmente, a estacionaridade constatada a partir de um valor limite estimado de 3,3 pontos percentuais para o Indicador de Compras de Bens Duráveis e de 3,6 pontos percentuais para o Indicador de Poupança permitem classificar seus históricos com indícios de saturação da capacidade de poupança e consumo dos indivíduos.

Electric Signaling and Pin2 Gene Expression on Different Abiotic Stimuli Depend on a Distinct Threshold Level of Endogenous Abscisic Acid in Several Abscisic Acid-Deficient Tomato Mutants1

Experiments were performed on three abscisic acid (ABA)-deficient tomato (Lycopersicon esculentum Mill.) mutants, notabilis, flacca, and sitiens, to investigate the role of ABA and jasmonic acid (JA) in the generation of electrical signals and Pin2 (proteinase inhibitor II) gene expression. We selected these mutants because they contain different levels of endogenous ABA. ABA levels in the mutant sitiens were reduced to 8% of the wild type, in notabilis they were reduced to 47%, and in flacca they were reduced to 21%. In wild-type and notabilis tomato plants the induction of Pin2 gene expression could be elicited by heat treatment, current application, or mechanical wounding. In flacca and sitiens only heat stimulation induced Pin2 gene expression. JA levels in flacca and sitiens plants also accumulated strongly upon heat stimulation but not upon mechanical wounding or current application. Characteristic electrical signals evolved in the wild type and in the notabilis and flacca mutants consisting of a fast action potential and a slow variation potential. However, in sitiens only heat evoked electrical signals; mechanical wounding and current application did not change the membrane potential. In addition, exogenous application of ABA to wild-type tomato plants induced transient changes in membrane potentials, indicating the involvement of ABA in the generation of electrical signals. Our data strongly suggest the presence of a minimum threshold value of ABA within the plant that is essential for the early events in electrical signaling and mediation of Pin2 gene expression upon wounding. In contrast, heat-induced Pin2 gene expression and membrane potential changes were not dependent on the ABA level but, rather, on the accumulation of JA.

Neuropharmacological basis of rTMS-induced analgesia: The role of endogenous opioids

We investigated the role of endogenous opioid systems in the analgesic effects induced by repetitive transcranial magnetic stimulation (rTMS). We compared the analgesic effects of motor cortex (M1) or dorsolateral prefrontal cortex (DLPFC) stimulation before and after naloxone or placebo treatment, in a randomized, double-blind crossover design, in healthy volunteers. Three groups of 12 volunteers were selected at random and given active stimulation (frequency 10 Hz, at 80% motor threshold intensity, 1500 pulses per session) of the right M1, active stimulation of the right DLPFC, or sham stimulation, during two experimental sessions 2 weeks apart. Cold pain thresholds and the intensity of pain induced by a series of fixed-temperature cold stimuli (5, 10, and 15 degrees C) were used to evaluate the analgesic effects of rTMS. Measurements were made at the left thenar eminence, before and 1 hour after the intravenous injection of naloxone (bolus of 0.1 mg/kg followed by a continuous infusion of 0.1 mg/kg/h until the end of rTMS) or placebo (saline). Naloxone injection significantly decreased the analgesic effects of M1 stimulation, but did not change the effects of rTMS of the DLPFC or sham rTMS. This study demonstrates, for the first time, the involvement of endogenous opioid systems in rTMS-induced analgesia. The differential effects of naloxone on M1 and DLPFC stimulation suggest that the analgesic effects induced by the stimulation of these 2 cortical sites are mediated by different mechanisms. (C) 2010 Published by Elsevier B.V. on behalf of International Association for the Study of Pain.

Detection of testosterone administration based on the carbon isotope ratio profiling of endogenous steroids: international reference populations of professional soccer players.

BACKGROUND AND OBJECTIVES: The determination of the carbon isotope ratio in androgen metabolites has been previously shown to be a reliable, direct method to detect testosterone misuse in the context of antidoping testing. Here, the variability in the 13C/12C ratios in urinary steroids in a widely heterogeneous cohort of professional soccer players residing in different countries (Argentina, Italy, Japan, South Africa, Switzerland and Uganda) is examined. METHODS: Carbon isotope ratios of selected androgens in urine specimens were determined using gas chromatography/combustion/isotope ratio mass spectrometry (GC-C-IRMS). RESULTS: Urinary steroids in Italian and Swiss populations were found to be enriched in 13C relative to other groups, reflecting higher consumption of C3 plants in these two countries. Importantly, detection criteria based on the difference in the carbon isotope ratio of androsterone and pregnanediol for each population were found to be well below the established threshold value for positive cases. CONCLUSIONS: The results obtained with the tested diet groups highlight the importance of adapting the criteria if one wishes to increase the sensitivity of exogenous testosterone detection. In addition, confirmatory tests might be rendered more efficient by combining isotope ratio mass spectrometry with refined interpretation criteria for positivity and subject-based profiling of steroids.

Changes in the vascular reactivity of the isolated tail arteries of spontaneous and renovascular hypertensive rats to endogenous and exogenous noradrenaline.

We have investigated the changes in the responses to noradrenaline of isolated tail arteries of spontaneously hypertensive (SHR) and renovascular hypertensive rats (Wistar-Kyoto: two-kidney, one-clip model, WKY:2K1C) compared with normotensive (Wistar-Kyoto, WKY) rats. Renovascular hypertension was induced by 4 weeks' unilateral renal artery clipping. Arteries were vasoconstricted with exogenous noradrenaline, electrical field stimulation or high potassium. The effects of the latter two stimuli were abolished by reserpine and so were presumably dependent on the presence of endogenous noradrenaline. In the SHR the maximal vasoconstriction produced by all three stimuli was greater than in WKY. Dose-response curves were steeper and there was no change in threshold. Vascular mass was greater. We interpret these results as showing an increase in vascular reactivity in the SHR caused by structural adaptation. The WKY:2K1C responses to noradrenaline could also be explained in terms of structural adaptation but there was no increase in vascular mass. Sensitivity to potassium and electrical stimulation was decreased, suggesting a defect in vascular neurotransmission. This was supported by the observations of a decreased arterial noradrenaline content and of decreased sensitivity to cocaine.

Analysis of the transcriptional activity of endogenous NFAT5 in primary cells using transgenic NFAT-luciferase reporter mice

Background: The transcription factor NFAT5/TonEBP regulates the response of mammalian cells to hypertonicity. However, little is known about the physiopathologic tonicity thresholds that trigger its transcriptional activity in primary cells. Wilkins et al. recently developed a transgenic mouse carrying a luciferase reporter (9xNFAT-Luc) driven by a cluster of NFAT sites, that was activated by calcineurin-dependent NFATc proteins. Since the NFAT site of this reporter was very similar to an optimal NFAT5 site, we tested whether this reporter could detect the activation of NFAT5 in transgenic cells.Results: The 9xNFAT-Luc reporter was activated by hypertonicity in an NFAT5-dependent manner in different types of non-transformed transgenic cells: lymphocytes, macrophages and fibroblasts. Activation of this reporter by the phorbol ester PMA plus ionomycin was independent of NFAT5 and mediated by NFATc proteins. Transcriptional activation of NFAT5 in T lymphocytes was detected at hypertonic conditions of 360–380 mOsm/kg (isotonic conditions being 300 mOsm/kg) and strongly induced at 400 mOsm/kg. Such levels have been recorded in plasma in patients with osmoregulatory disorders and in mice deficient in aquaporins and vasopressin receptor. The hypertonicity threshold required to activate NFAT5 was higher in bone marrow-derived macrophages (430 mOsm/kg) and embryonic fibroblasts (480 mOsm/kg). Activation of the 9xNFAT-Luc reporter by hypertonicity in lymphocytes was insensitive to the ERK inhibitor PD98059, partially inhibited by the PI3-kinase inhibitor wortmannin (0.5 μM) and the PKA inhibitor H89, and substantially downregulated by p38 inhibitors (SB203580 and SB202190) and by inhibition of PI3-kinase-related kinases with 25 μM LY294002. Sensitivity of the reporter to FK506 varied among cell types and was greater in primary T cells than in fibroblasts and macrophages.Conclusion: Our results indicate that NFAT5 is a sensitive responder to pathologic increases in extracellular tonicity in T lymphocytes. Activation of NFAT5 by hypertonicity in lymphocytes was mediated by a combination of signaling pathways that differed from those required in other cell types. We propose that the 9xNFAT-Luc transgenic mouse model might be useful to study the physiopathological regulation of both NFAT5 and NFATc factors in primary cells.

Endogenous labor market participation and the business cycle

Existing models of equilibrium unemployment with endogenous labor market participation are complex, generate procyclical unemployment rates and cannot match unemployment variability relative to GDP. We embed endogenous participation in a simple, tractable job market matching model, show analytically how variations in the participation rate are driven by the cross-sectional density of home productivity near the participation threshold, andhow this density translates into an extensive-margin labor supply elasticity. A calibration of the model to macro data not only matches employment and participation variabilities but also generates strongly countercyclical unemployment rates. With some wage rigidity the model also matches unemployment variations well. Furthermore, the labor supply elasticity implied by our calibration is consistent with microeconometric evidence for the US.

Investigations on hydrogen isotope ratios of endogenous urinary steroids: reference-population-based thresholds and proof-of-concept.

Carbon isotope ratio (CIR) analysis has been routinely and successfully used in sports drug testing for many years to uncover the misuse of endogenous steroids. One limitation of the method is the availability of steroid preparations exhibiting CIRs equal to endogenous steroids. To overcome this problem, hydrogen isotope ratios (HIR) of endogenous urinary steroids were investigated as a potential complement; results obtained from a reference population of 67 individuals are presented herein. An established sample preparation method was modified and improved to enable separate measurements of each analyte of interest where possible. From the fraction of glucuronidated steroids; pregnanediol, 16-androstenol, 11-ketoetiocholanolone, androsterone (A), etiocholanolone (E), dehydroepiandrosterone (D), 5α- and 5β-androstanediol, testosterone and epitestosterone were included. In addition, sulfate conjugates of A, E, D, epiandrosterone and 17α- and 17β-androstenediol were considered and analyzed after acidic solvolysis. The obtained results enabled the calculation of the first reference-population-based thresholds for HIR of urinary steroids that can readily be applied to routine doping control samples. Proof-of-concept was accomplished by investigating urine specimens collected after a single oral application of testosterone-undecanoate. The HIR of most testosterone metabolites were found to be significantly influenced by the exogenous steroid beyond the established threshold values. Additionally, one regular doping control sample with an extraordinary testosterone/epitestosterone ratio of 100 without suspicious CIR was subjected to the complementary methodology of HIR analysis. The HIR data eventually provided evidence for the exogenous origin of urinary testosterone metabolites. Despite further investigations on HIR being advisable to corroborate the presented reference-population-based thresholds, the developed method proved to be a new tool supporting modern sports drug testing procedures.

Peripheral T cell activation and deletion induced by transfer of lymphocyte subsets expressing endogenous or exogenous mouse mammary tumor virus.

Murine T cell reactivity with products of the minor lymphocyte stimulatory (Mls) locus correlates with the expression of particular variable (V) domains of the T cell receptor (TCR) beta chain. It was recently demonstrated that Mls antigens are encoded by an open reading frame (ORF) in the 3' long terminal repeat of either endogenous or exogenous mouse mammary tumor virus (MMTV). Immature thymocytes expressing reactive TCR-V beta domains are clonally deleted upon exposure to endogenous Mtv's. Mature T cells proliferate vigorously in response to Mls-1a (Mtv-7) in vivo, but induction of specific anergy and deletion after exposure to Mtv-7-expressing cells in the periphery has also been described. We show here that B cells and CD8+ (but not CD4+) T cells from Mtv-7+ mice efficiently induce peripheral deletion of reactive T cells upon transfer to Mtv-7- recipients, whereas only B cells stimulate specific T cell proliferation in vivo. In contrast to endogenous Mtv-7, transfer of B, CD4+, or CD8+ lymphocyte subsets from mice maternally infected with MMTV(SW), an infectious homologue of Mtv-7, results in specific T cell deletion in the absence of a detectable proliferative response. Finally, we show by secondary transfers of infected cells that exogenous MMTV(SW) is transmitted multidirectionally between lymphocyte subsets and ultimately to the mammary gland. Collectively our data demonstrate heterogeneity in the expression and/or presentation of endogenous and exogenous MMTV ORF by lymphocyte subsets and emphasize the low threshold required for induction of peripheral T cell deletion by these gene products.

The risk factors for fractures and trabecular bone-score value in patients with endogenous Cushing's syndrome.

In a cohort study of 182 consecutive patients with active endogenous Cushing's syndrome, the only predictor of fracture occurrence after adjustment for age, gender bone mineral density (BMD) and trabecular bone score (TBS) was 24-h urinary free cortisol (24hUFC) levels with a threshold of 1472 nmol/24 h (odds ratio, 3.00 (95 % confidence interval (CI), 1.52-5.92); p = 0.002). INTRODUCTION: The aim was to estimate the risk factors for fracture in subjects with endogenous Cushing's syndrome (CS) and to evaluate the value of the TBS in these patients. METHODS: All enrolled patients with CS (n = 182) were interviewed in relation to low-traumatic fractures and underwent lateral X-ray imaging from T4 to L5. BMD measurements were performed using a DXA Prodigy device (GEHC Lunar, Madison, Wisconsin, USA). The TBS was derived retrospectively from existing BMD scans, blinded to clinical outcome, using TBS iNsight software v2.1 (Medimaps, Merignac, France). Urinary free cortisol (24hUFC) was measured by immunochemiluminescence assay (reference range, 60-413 nmol/24 h). RESULTS: Among enrolled patients with CS (149 females; 33 males; mean age, 37.8 years (95 % confidence interval, 34.2-39.1); 24hUFC, 2370 nmol/24 h (2087-2632), fractures were confirmed in 81 (44.5 %) patients, with 70 suffering from vertebral fractures, which were multiple in 53 cases; 24 patients reported non-vertebral fractures. The mean spine TBS was 1.207 (1.187-1.228), and TBS Z-score was -1.86 (-2.07 to -1.65); area under the curve (AUC) was used to predict fracture (mean spine TBS) = 0.548 (95 % CI, 0.454-0.641)). In the final regression model, the only predictor of fracture occurrence was 24hUFC levels (p = 0.001), with an increase of 1.041 (95 % CI, 1.019-1.063), calculated for every 100 nmol/24-h cortisol elevation (AUC (24hUFC) = 0.705 (95 % CI, 0.629-0.782)). CONCLUSIONS: Young patients with CS have a low TBS. However, the only predictor of low traumatic fracture is the severity of the disease itself, indicated by high 24hUFC levels.

Participation of endogenous opioids in the antinociception induced by resistance exercise in rats

Exercise is a low-cost intervention that promotes health and contributes to the maintenance of the quality of life. The present study was designed to investigate the influence of different resistance exercise protocols on the nociceptive threshold of rats. Female Wistar rats were used to perform exercises in a weight-lifting exercise model. The following groups were examined (N = 6 per group): untrained rats (control group); an acute protocol group consisting of rats submitted to 15 sets of 15 repetitions of resistance exercise (acute group); rats exercised with 3 sets of 10 repetitions, three times per week for 12 weeks (trained group), and a group consisting of trained rats that were further submitted to the acute protocol (trained-acute group). The nociceptive threshold was measured by the paw-withdrawal test, in which the withdrawal threshold (escape reaction) was measured by an apparatus applying force to the plantar surface of the animal paw. The opioid antagonist naloxone (2 mg/kg) was administered subcutaneously 10 min before the exercise protocols. The trained group demonstrated antinociception only up to day 45 of the 12-week training period. A significant increase (37%, P < 0.05) in the nociceptive threshold was produced immediately after exercise, decreasing to 15% after 15 min, when the acute exercise protocol was used. Naloxone reversed this effect. These data show that the acute resistance exercise protocol was effective in producing antinociception for 15 min. This antinociceptive effect is mediated by the activation of opioid receptors.

A low threshold level of expression of mutant-template telomerase RNA inhibits human tumor cell proliferation

The ribonucleoprotein telomerase synthesizes telomeric DNA by copying an intrinsic RNA template. In most cancer cells, telomerase is highly activated. Here we report a telomerase-based antitumor strategy: expression of mutant-template telomerase RNAs in human cancer cells. We expressed mutant-template human telomerase RNAs in prostate (LNCaP) and breast (MCF-7) cancer cell lines. Even a low threshold level of expression of telomerase RNA gene constructs containing various mutant templates, but not the control wild-type template, decreased cellular viability and increased apoptosis. This occurred despite the retention of normal levels of the endogenous wild-type telomerase RNA and endogenous wild-type telomerase activity and unaltered stable telomere lengths. In vivo tumor xenografts of a breast cancer cell line expressing a mutant-template telomerase RNA also had decreased growth rates. Therefore, mutant-template telomerase RNAs exert a strongly dominant-negative effect on cell proliferation and tumor growth. These results support the potential use of mutant-template telomerase RNA expression as an antineoplastic strategy.

Islet Neogenesis-associated Protein (ingap): The Role Of Its Endogenous Production As A Positive Modulator Of Insulin Secretion.

Islet neogenesis-associated protein (INGAP) is a peptide found in pancreatic exocrine-, duct- and islet- non-β-cells from normal hamsters. Its increase induced by either its exogenous administration or by the overexpression of its gene enhances β-cell secretory function and increases β-cell mass by a combination of stimulation of cell replication and islet neogenesis and reduction of β-cell apoptosis. We studied the potential modulatory role of endogenous INGAP in insulin secretion using two different experimental approaches. Hamster islets transfected with INGAP-small interfering RNA (INGAP-siRNA) were used to study glucose-stimulated insulin secretion (GSIS). In parallel, freshly isolated islets were incubated with high glucose and the same concentration of either a specific anti-INGAP rabbit serum or normal rabbit serum. INGAP-siRNA transfected islets reduced their INGAP mRNA and protein content by 35.1% and 47.2%, respectively whereas GSIS decreased by 25.8%. GSIS by transfected islets attained levels comparable to those recorded in control islets when INGAP pentadecapeptide (INGAP-PP) was added to the culture medium. INGAP antibody in the medium decreased significantly GSIS in a dose-dependent manner. These results indicate that endogenous INGAP plays a physiological positive modulatory role in insulin secretion, supporting its possible use in the treatment of prediabetes and Type 2 diabetes.

Pain Threshold And Sleep Quality In Women With Endometriosis.

Pain is a common complaint in women with endometriosis and can be influenced by many variables, including sleep disorders; however, no data are available on the sleep quality of women with endometriosis or on the correlation between sleep quality and pain. The 510 volunteers included in this study were divided into two groups: 257 women with a laparoscopic and histopathological diagnosis of endometriosis and 253 women with no history of endometriosis and no endometriosis-related symptoms. The volunteers answered two questionnaires: the Post-Sleep Inventory to evaluate sleep quality and the International Physical Activity Questionnaire to assess their level of physical activity. Pain was evaluated using a visual analogue scale (VAS) and women were also submitted to a physical examination, during which their pain threshold was assessed at 20 different body sites. Sleep quality was significantly poorer in women with endometriosis compared to women without the disease. The pain threshold was significantly lower in the greater trochanter and abdomen in women with endometriosis when compared to women without the disease; however, there was no difference in VAS pain score between the groups. The higher the VAS pain score, the lower the Post-Sleep Inventory score. Additionally, there was a significant positive correlation between the pain threshold at some body sites and sleep quality. Sleep quality was poorer and the pain threshold at certain body sites was lower in the group of women with endometriosis.

Hypobromous Acid, A Powerful Endogenous Electrophile: Experimental And Theoretical Studies.

Hypobromous acid (HOBr) is an inorganic acid produced by the oxidation of the bromide anion (Br(-)). The blood plasma level of Br(-) is more than 1,000-fold lower than that of chloride anion (Cl(-)). Consequently, the endogenous production of HOBr is also lower compared to hypochlorous acid (HOCl). Nevertheless, there is much evidence of the deleterious effects of HOBr. From these data, we hypothesized that the reactivity of HOBr could be better associated with its electrophilic strength. Our hypothesis was confirmed, since HOBr was significantly more reactive than HOCl when the oxidability of the studied compounds was not relevant. For instance: anisole (HOBr, k2=2.3×10(2)M(-1)s(-1), HOCl non-reactive); dansylglycine (HOBr, k2=7.3×10(6)M(-1)s(-1), HOCl, 5.2×10(2)M(-1)s(-1)); salicylic acid (HOBr, k2=4.0×10(4)M(-1)s(-1), non-reactive); 3-hydroxybenzoic acid (HOBr, k2=5.9×10(4)M(-1)s(-1), HOCl, k2=1.1×10(1)M(-1)s(-1)); uridine (HOBr, k2=1.3×10(3)M(-1)s(-1), HOCl non-reactive). The compounds 4-bromoanisole and 5-bromouridine were identified as the products of the reactions between HOBr and anisole or uridine, respectively, i.e. typical products of electrophilic substitutions. Together, these results show that, rather than an oxidant, HOBr is a powerful electrophilic reactant. This chemical property was theoretically confirmed by measuring the positive Mulliken and ChelpG charges upon bromine and chlorine. In conclusion, the high electrophilicity of HOBr could be behind its well-established deleterious effects. We propose that HOBr is the most powerful endogenous electrophile.