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We investigate the thermodynamic uncertainty relations (TURs) in mesoscopic devices for all universal symmetry classes of Wigner-Dyson and Dirac (chiral). The observables of interest include the TUR (MS), which is defined in terms of the ratio between the mean noise and mean conductance, as well as a new TUR (R) proposed in this article, which is based on the ensemble mean of the noise-to-conductance ratio. A detailed study is made on the quantum interference corrections associated with the TURs. We also analyze the influence of orbital and sublattice/chiral degrees of freedom for the validity of the observables in these chaotic mesoscopic billiards. Our investigation is based on the concatenation between the Landauer-Büttiker theory, the Mahaux-Wendeinmüller theory, and the TURs. We simulate the universal mesoscopic chaotic quantum dots using the random-matrix theory and compare our numerical results with the pertinent experimental data. The results were obtained for a different number of channels and tunneling rates that vary from the opaque to the ideal regime and, in all cases, demonstrate a clear phenomenological distinction between the TURs. In particular, the opaque regime engenders remarkable differences between the observables, even in the semiclassical regime, which characterizes a clear violation of the central limit theorem. Furthermore, we show that the phenomenology of the quantum interference corrections is strikingly robust, surprisingly exhibiting an order of magnitude greater than the supposedly leading semiclassical term for the TUR (R).
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BACKGROUND: Ecological disasters create dramatic changes as man-made and natural ecosystems adapt to their effects. In 2017, Hurricanes Irma and María devastated Puerto Rico. Public focus after such traumatic ecological events often neglects pre-existing community dynamics, heterogeneity of lived experience, and complexity of decision-making in the disaster context. We intended to better understand the lived experience of this ecological trauma in communities across ecosystems in Puerto Rico and among those displaced to Florida. METHOD: We used the Critical Medical Ecological (CME) framework to assess the relative contribution of ecological dimensions on lived experience across community levels and time. We used qualitative methods with emic coding and etic mapping of salient constructs to the ecological model. In total, 96 people participated in 23 discussion encounters. Two people coded interviews in Spanish using Dedoose. We identified common themes in sequential order mapped to elements of the CME to approximate the participants' temporal experience. RESULTS: Codes applied to the period of the hurricane's landfall, traverse, and exit were markedly distinct from the other two periods (before and after) examined in this study: the experience of the hurricane's strike was highly personal and, at this level, reflected a mix of sociocultural, biological, and abiotic factors. After the hurricanes, social and community factors re-emerged while new risks and conditions arose that were biological (e.g., leptospirosis, no food or water) or abiotic (e.g., unusable roads/bridges, structures destroyed), but created ongoing stressors and social needs for communities. As we found, the dynamics of the social and household landscape sometimes involved the decision to leave Puerto Rico altogether, or forced people to continually face and adapt to the ongoing collapse in basic services that were only slowly and differentially restored. CONCLUSION: Lived experience across each stage of the hurricanes differed substantially from one another. Communities disrupted by ecological disaster are also frequently entangled within global economic and political histories and dependencies that could preclude recovery. Island nations are especially vulnerable to both climate-induced ecological change and political-economic exploitation. The ongoing health effect of the hurricane remains palpable in many communities of Puerto Rico and among the diaspora in Florida.
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Tempestades Ciclônicas , Dípteros , Desastres , Animais , Ecossistema , Humanos , Porto RicoRESUMO
BACKGROUND: Two devastating sequential hurricanes impacted Puerto Rico during September of 2017. The hurricanes were traumatic and created social and ecological upheaval throughout Puerto Rico, and subsequently in communities of Central Florida where affected Puerto Ricans migrated. The 2017 hurricane season exposed and exacerbated previous long-standing socio-political, economic, environmental, and health crises, generating a humanitarian emergency in the country. The consequences of these human-ecological disasters destroyed much of Puerto Rico's residential and environmental infrastructure, displacing thousands of people and resulting in an unprecedented migration to the United States. We report on the lived experience of the investigator team and partnership in conducting community-based formative research subsequent to this disaster, research that aimed to identify salient issues relating to the impact of Hurricanes Irma and María on Puerto Rican communities both in Puerto Rico and in Central Florida. DISCUSSION: The challenges faced during the conduct of this research include but are not limited to (1) emotional distress of participants and team members, (2) access to affected populations, and (3) precarious environmental factors, such as unstable infrastructure. To address these challenges, the researchers applied a Critical Medical Ecological paradigm along with qualitative methods to assist constructing explanatory models while obtaining internally-valid (from the community perspective), cathartic narrative accounts of the lived experience of hurricane survivors. The experience of the research team may help inform other investigators conducting applied research during a humanitarian crisis. CONCLUSION: Lessons learned in this research included: (1) usefulness of applying the Critical Medical Ecological model in the development of the project, (2) incorporating participation and methods that prioritize authenticity, (3) understanding the trauma experience and using study methods sensitive to it, and (4) innovating with best approaches to conduct the study given the challenges in post-hurricane Puerto Rico. These lessons could provide new insights on how to conduct in-depth participatory health research with community members who have been traumatized and - often - displaced. This research also demonstrates the value of pre-existing partnerships, critical consciousness in the field team, and medical ecological modeling as experiential for organizing complex, inter-related, multi-level variables that explain community and individual impact of environmental disasters.
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Tempestades Ciclônicas , Desastres , Florida , Hispânico ou Latino , Humanos , Porto Rico , Estados UnidosRESUMO
Oculocutaneous albinism (OCA) increases predisposition to skin malignancies. Nevertheless, the differential diagnosis between melanoma and naevi in patients with OCA is still challenging, because pigmentary lesions have rarely been described in this population. We aimed to describe the dermoscopic patterns of naevi in patients with OCA. We prospectively evaluated 83 naevi from 37 patients with OCA in a single centre in Brazil. Lesions were analysed by eye and by dermoscopy and were grouped by dermoscopic pattern. Eight main patterns were identified: homogeneous structureless pattern (n = 28; 33.7%), globular pattern (n = 27; 32.5%), reticular pattern (n = 8; 9.6%), peripheral reticular pattern with central hypopigmentation (n = 8; 9.6%), peripheral globules (n = 8; 9.6%), irregular brown globules with pink background (n = 2; 2.4%), reticular globular disorganized pattern (n = 1; 1.2%) and peripheral reticular globular with central hypopigmentation (n = 1; 1.2%). We found previously undescribed dermoscopic patterns in patients with OCA, in addition to confirming previously described patterns. These descriptions may help the understanding of pigmented naevi in patients with OCA.
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Albinismo Oculocutâneo/patologia , Dermoscopia , Nevo/patologia , Neoplasias Cutâneas/patologia , Adolescente , Albinismo Oculocutâneo/complicações , Brasil , Criança , Feminino , Humanos , Masculino , Nevo/complicações , Estudos Prospectivos , Neoplasias Cutâneas/complicações , Adulto JovemRESUMO
The broad-snouted caiman (Caiman latirostris) is a crocodilian species that inhabits South American wetlands. As in all other crocodilians, the egg incubation temperature during a critical thermo-sensitive window (TSW) determines the sex of the hatchlings, a phenomenon known as temperature-dependent sex determination (TSD). In C. latirostris, we have shown that administration of 17-ß-estradiol (E2) during the TSW overrides the effect of the male-producing temperature, producing phenotypic females (E2SD-females). Moreover, the administration of E2 during TSW has been proposed as an alternative way to improve the recovery of endangered reptile species, by skewing the population sex ratio to one that favors females. However, the ovaries of E2SD-female caimans differ from those of TSD-females. In crocodilians, the external genitalia (i.e. clitero-penis structure or phallus) are sexually dimorphic and hormone-sensitive. Despite some morphological descriptions aimed to facilitate sexing, we found no available data on the C. latirostris phallus histoarchitecture or hormone dependence. Thus, the aims of this study were: (1) to establish the temporal growth pattern of the phallus in male and female caimans; (2) to evaluate histo-morphological features and the expression of estrogen receptor alpha (ERα) and androgen receptor (AR) in the phallus of male and female pre-pubertal juvenile caimans; and (3) to determine whether the phallus of TSD-females differs from the phallus of E2SD-females. Our results demonstrated sexually dimorphic differences in the size and growth dynamics of the caiman external genitalia, similarities in the shape and spatial distribution of general histo-morphological compartments, and sexually dimorphic differences in innervation, smooth muscle fiber distribution, collagen organization, and ERα and AR expressions. The external genitalia of E2SD-females differed from that of TSD-females in many histological features and in the expression of ERα and AR, resembling patterns described in males. Our results alert on the effects of estrogen agonist exposure during TSW and suggest that caution must be taken regarding the use of E2SD as a procedure for wildlife population management.
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Jacarés e Crocodilos/fisiologia , Genitália Feminina/fisiologia , Hormônios Esteroides Gonadais/metabolismo , Processos de Determinação Sexual , Temperatura , Jacarés e Crocodilos/anatomia & histologia , Animais , Proliferação de Células/efeitos dos fármacos , Colágeno/metabolismo , Desmina/metabolismo , Feminino , Genitália Feminina/citologia , Genitália Feminina/crescimento & desenvolvimento , Masculino , Receptores de Superfície Celular/metabolismoRESUMO
This work deals with the effects of an apex predator on the cyclic competition among three distinct species that follow the rules of the rock-paper-scissors game. The investigation develops standard stochastic simulations but is motivated by a procedure which is explained in the work. We add the apex predator as the fourth species in a system that contains three species that evolve following the standard rules of migration, reproduction, and predation, and study how the system evolves in this new environment, in comparison with the case in the absence of the apex predator. The results show that the apex predator engenders the tendency to spread uniformly in the lattice, contributing to destroy the spiral patterns, keeping biodiversity but diminishing the average size of the clusters of the species that compete cyclically.
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Cadeia Alimentar , Modelos Biológicos , Comportamento Predatório , Distribuição Animal , Animais , Simulação por Computador , Teoria dos Jogos , Jogos Experimentais , Reprodução , Processos EstocásticosRESUMO
GST-tagged proteins are important tools for the production of recombinant proteins. Removal of GST tag from its fusion protein, frequently by harsh chemical treatments or proteolytic methods, is often required. Thus, the monitoring of the proteins in tag-free form requires a significant effort to determine the remnants of GST during purification process. In the present study, we developed both a conventional enzyme-linked immunosorbent assay (ELISA) and an immuno-polymerase chain reaction (IPCR) assay, both specific for detection of recombinant GST (rGST). rGST was expressed in Escherichia coli JM109, using a pGEX4T-3 vector, and several anti-rGST monoclonal antibodies were generated using hybridoma technology. Two of these were rationally selected as capture and detection antibodies, allowing the development of a sandwich ELISA with a limit of detection (LOD) of 0.01 µg/ml. To develop the rGST-IPCR assay, we selected "Universal-IPCR" format, comprising the biotin-avidin binding as the coupling system. In addition, the rGST-IPCR was developed in standard PCR tubes, and the surface adsorption of antibodies on PCR tubes, the optimal neutravidin concentrations, the generation of a reporter DNA and the concentration effect were studied and determined. Under optimized assay conditions, the rGST-IPCR assay provided a 100-fold increase in the LOD as well as an expanded working range, in comparison with rGST-ELISA. The proposed method exhibited great potentiality for application in several fields in which measurement of very low levels of GST is necessary, and might provide a model for other IPCR assays.
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Anticorpos Monoclonais/biossíntese , Ensaio de Imunoadsorção Enzimática/métodos , Escherichia coli/genética , Glutationa Transferase/isolamento & purificação , Proteínas de Helminto/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Schistosoma japonicum/química , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/isolamento & purificação , Avidina/química , Biotina/química , Clonagem Molecular , Escherichia coli/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Glutationa Transferase/biossíntese , Glutationa Transferase/genética , Proteínas de Helminto/biossíntese , Proteínas de Helminto/genética , Hibridomas/imunologia , Hibridomas/patologia , Limite de Detecção , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Schistosoma japonicum/enzimologia , Baço/citologia , Baço/imunologiaRESUMO
We demonstrate the presence of chaos in stochastic simulations that are widely used to study biodiversity in nature. The investigation deals with a set of three distinct species that evolve according to the standard rules of mobility, reproduction and predation, with predation following the cyclic rules of the popular rock, paper and scissors game. The study uncovers the possibility to distinguish between time evolutions that start from slightly different initial states, guided by the Hamming distance which heuristically unveils the chaotic behavior. The finding opens up a quantitative approach that relates the correlation length to the average density of maxima of a typical species, and an ensemble of stochastic simulations is implemented to support the procedure. The main result of the work shows how a single and simple experimental realization that counts the density of maxima associated with the chaotic evolution of the species serves to infer its correlation length. We use the result to investigate others distinct complex systems, one dealing with a set of differential equations that can be used to model a diversity of natural and artificial chaotic systems, and another one, focusing on the ocean water level.
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Modelos Biológicos , Dinâmica não Linear , Processos Estocásticos , Algoritmos , Evolução Biológica , Simulação por ComputadorRESUMO
UNLABELLED: The hypertensive disorders of pregnancy complicate up to 10% of pregnancies worldwide and are a leading cause of maternal, foetal, and neonatal morbidity and mortality. The aim of this study was to present an overview of recent studies addressing offspring's medium and long-term health outcomes after intrauterine exposure to maternal hypertension. A search on PubMed/MEDLINE and Bireme databases was conducted to identify observational studies that reported any offspring outcome measured after the 6th month of life. The search was limited to studies published after May 2008. Forty-five articles were included and categorized into four groups of outcomes: cardiovascular, immune, metabolic and behavioural/neurological effects. According to our findings, hypertensive disorders of pregnancy had an overall negative impact on offspring's cardiovascular, immune and neurological health, although not all parameters analysed in each group had consistent results among studies. The most prominent and reliable associations were verified between gestational hypertension and higher offspring's blood pressure and between preeclampsia and offspring's lower cognitive functioning. In the metabolic outcomes, body composition had conflicting results among papers, while all studies that examined blood biomarkers showed no evidence that preeclampsia or gestational hypertension could be associated with an alteration of this metabolic outcomes. Most included studies were highly heterogeneous regarding the measure of outcomes and covariables used for adjustments. Future studies should consider using the same protocols and cut-off points already published so that results can be better compared and summarized. This review was registered in PROSPERO. REGISTRATION NUMBER: CRD42015020838.
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Doenças Cardiovasculares/etiologia , Transtornos Cognitivos/etiologia , Hipertensão Induzida pela Gravidez/fisiopatologia , Doenças Metabólicas/etiologia , Doenças Cardiovasculares/patologia , Transtornos Cognitivos/patologia , Feminino , Humanos , Recém-Nascido , Doenças Metabólicas/patologia , GravidezRESUMO
We derive analytical expressions for the correlation functions of the electronic conductance fluctuations of an open quantum dot under several conditions. Both the variation of energy and that of an external parameter, such as an applied perpendicular or parallel magnetic fields, are considered in the general case of partial openness. These expressions are then used to obtain the ensemble-averaged density of maxima, a measure recently suggested to contain invaluable information concerning the correlation widths of chaotic systems. The correlation width is then calculated for the case of energy variation, and a significant deviation from the Weisskopf estimate is found in the case of two terminals. The results are extended to more than two terminals. All of our results are analytical. The use of these results in other fields, such as nuclei, where the system can only be studied through a variation of the energy, is then discussed.
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We present analytical and numerical results that demonstrate the presence of the Braess paradox in chaotic quantum dots. The paradox that we identify, originally perceived in classical networks, shows that the addition of more capacity to the network can suppress the current flow in the universal regime. We investigate the weak localization term, showing that it presents the paradox encoded in a saturation minimum of the conductance, under the presence of hyperflow in the external leads. In addition, we demonstrate that the weak localization suffers a transition signal depending on the overcapacity lead and presents an echo on the magnetic crossover before going to zero due to the full time-reversal symmetry breaking. We also show that the quantum interference contribution can dominate the Ohm term in the presence of constrictions and that the corresponding Fano factor engenders an anomalous behavior.
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We investigate the correlation functions of mesoscopic electronic transport in open chaotic quantum dots with finite tunnel barriers in the crossover between Wigner-Dyson ensembles. Using an analytical stub formalism, we show the emergence of a depletion and amplification of conductance fluctuations as a function of tunnel barriers for both parametric variations of electron energy and magnetoconductance fields. Furthermore, even for pure Dyson ensembles, correlation functions of conductance fluctuations in chaotic quantum dots can exhibit anticorrelation. Experimental support to our findings is pointed out.
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We present a simple measure of the conductance fluctuations in open ballistic chaotic quantum dots, extending the number of maxima method originally proposed for the statistical analysis of compound nuclear reactions. The average number of extreme points (maxima and minima) in the dimensionless conductance T as a function of an arbitrary external parameter Z is directly related to the autocorrelation function of T(Z). The parameter Z can be associated with an applied gate voltage causing shape deformation in quantum dot, an external magnetic field, the Fermi energy, etc. The average density of maxima is found to be <ρ(Z)>=α(Z)/Z(c), where α(Z) is a universal constant and Z(c) is the conductance autocorrelation length, which is system specific. The analysis of <ρ(Z)> does not require large statistic samples, providing a quite amenable way to access information about parametric correlations, such as Z(c).
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This study examines the effects of neonatal exposure to the endocrine disruptor bisphenol A (BPA) on the neural network that controls estrous cyclicity. From postnatal day 1 (PND1) to PND7, female pups were injected with vehicle (control) or BPA (BPA.05: 0.05mg/kg-d, BPA20: 20mg/kg-d). At PND100 BPA.05-females showed alterations in estrous cyclicity and BPA20-females were incapable of producing an estradiol-induced LH surge. By real-time PCR we determined that hypothalamic expression of mature LH-releasing hormone (LHRH) mRNA was increased in BPA.05 and decreased in BPA20-females. Furthermore, unprocessed intron A-containing LHRH RNA was decreased in the cytoplasm of hypothalamic cells of both groups. Immunohistochemistry revealed that estrogen receptor alpha protein was up-regulated in anteroventral periventricular and down-regulated in arcuate nucleus of both groups. Our results show that BPA permanently disrupts hypothalamic LHRH pre-mRNA processing and steroid receptors expression in nuclei that control estrous cyclicity in adult rats.
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Disruptores Endócrinos/toxicidade , Receptor alfa de Estrogênio/metabolismo , Ciclo Estral/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo/efeitos dos fármacos , Fenóis/toxicidade , Precursores de RNA/metabolismo , Animais , Animais Recém-Nascidos , Compostos Benzidrílicos , Citoplasma/metabolismo , Relação Dose-Resposta a Droga , Disruptores Endócrinos/administração & dosagem , Ciclo Estral/sangue , Ciclo Estral/metabolismo , Feminino , Hormônio Liberador de Gonadotropina/genética , Hipotálamo/metabolismo , Hipotálamo/patologia , Íntrons , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Rede Nervosa/efeitos dos fármacos , Rede Nervosa/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Especificidade de Órgãos , Fenóis/administração & dosagem , RNA Mensageiro/metabolismo , Ratos , Ratos WistarRESUMO
This study examines the effects of neonatal exposure to the endocrine disruptor bisphenol A (BPA) on the hypothalamic circuitry controlling the female sexual behaviors of adult rats. From postnatal day 1 (PND1) to PND7, pups were injected with corn oil (control) or BPA (BPA20: 20mg/kg-d; BPA.05: 0.05 mg/kg-d) and at PND85 the rats were bilaterally ovariectomized (OVX). At PND100, OVX-rats received estradiol alone or estradiol and progesterone to evaluate estrogen-dependent gene expression in the hypothalamus and sexual behavior. In BPA-exposed females, estrogen receptor alpha (ER alpha) expression was down-regulated in both the medial preoptic (MPN) and ventromedial nucleus (VMHvl), while repressor of estrogen receptor activity (REA) expression was up-regulated in the VMHvl. Interestingly, BPA-exposed females displayed significantly lower levels of proceptive behavior. Our results show that BPA permanently alters the hypothalamic estrogen-dependent mechanisms that govern sexual behavior in the adult female rat.
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Estrogênios não Esteroides/farmacologia , Fenóis/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Compostos Benzidrílicos , Relação Dose-Resposta a Droga , Estradiol/metabolismo , Receptor alfa de Estrogênio/análise , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Imunofluorescência , Imuno-Histoquímica , Ovariectomia , Ratos , Ratos Wistar , Receptores de Progesterona/metabolismoRESUMO
Normal parturition in guinea-pig involves changes in responsiveness of the genital tract to estrogen and progesterone. To better characterize endocrine control of guinea-pig parturition, protein and mRNA expression of estrogen receptor-alpha (ERalpha) and progesterone receptor (PR) were quantitatively evaluated in lower (LUS) and upper (UUS) uterine segments, cervix (C) and pubic symphyseal ligament (PSL) at three stages of pregnancy (established based on interpubic distance, 0mm: non-relaxed group, 4-6mm: 5 days before parturition, 11-14 mm: 1-2 days prepartum) and immediately after parturition. Towards parturition, no changes in PR mRNA levels were recorded in the UUS, whereas the LUS displayed a gradual increase. PR transcripts exhibited decreased levels during parturition in C and PSL. Levels of PR mRNA were increased in the LUS compared with that of the UUS only at parturition. Regarding protein expression during parturition, PR levels decreased in the UUS whereas in the LUS increased. In C and PSL, PR protein expression decreased 1-2 days prepartum and remained low during parturition. None of the regions studied showed changes in mRNA or protein expression of ERalpha. Therefore, functional regionalization of the guinea-pig genital tract is associated with changes in the spatio-temporal pattern of PR expression as parturition approaches.
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Genitália Feminina/metabolismo , Cobaias , Parto/fisiologia , Prenhez/metabolismo , Receptores de Progesterona/metabolismo , Animais , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Genitália Feminina/anatomia & histologia , Cobaias/anatomia & histologia , Cobaias/fisiologia , Humanos , Gravidez , Receptores de Progesterona/genética , Fatores de TempoRESUMO
Vascular growth of the uterine cervix during pregnancy is associated with mast cell (MC) degranulation. To better understand the mechanism underlying this process, uterine cervices of intact pregnant rats were dissected and endothelial cell proliferation was measured by a bromodeoxyuridine incorporation technique. Total vascular endothelial growth factor (VEGF) mRNA expression and the relative abundance of VEGF splice variants (120, 164, and 188) were determined by RT-PCR. VEGF protein expression was evaluated by immunohistochemistry. To investigate the role of MCs on cervical angiogenesis, a second set of pregnant animals were treated with an MC stabilizer (disodium cromoglycate) to inhibit MC degranulation. Furthermore, 17beta-estradiol (E(2)) serum levels were established by RIA. In intact pregnant rats, VEGF mRNA expression was positively correlated with endothelial cell proliferation and circulating E(2) levels. All selected splice variants of VEGF gene were detected and their relative abundance did not show any change throughout pregnancy. Animals treated with disodium cromoglycate showed a decrease in endothelial cell proliferation and in VEGF mRNA expression compared with controls. Relative abundance of VEGF mRNA splice variants and E(2) serum levels showed no differences between these experimental groups. These results show a time-dependent correlation between VEGF mRNA expression and E(2) serum levels in the uterine cervix of intact pregnant rats, while MC stabilizer-treated animals reduced the VEGF expression without modifying E(2) serum levels. We suggest that cervical angiogenesis during pregnancy could be regulated by a mechanism which involves endogenous E(2) and chemical mediators stored in MC granules via a VEGF-dependent pathway.
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Colo do Útero/citologia , Mastócitos/fisiologia , Prenhez/fisiologia , RNA Mensageiro/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Processamento Alternativo , Animais , Degranulação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Colo do Útero/irrigação sanguínea , Colo do Útero/metabolismo , Cromolina Sódica/farmacologia , Estradiol/sangue , Feminino , Imuno-Histoquímica , Neovascularização Fisiológica , Gravidez , RNA Mensageiro/análise , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
The gene for estrogen receptor alpha (ER alpha) has been shown to be under complex hormonal control and its activity can be regulated by mRNA alternative splicing. Here we examined the regulation of ER alpha transcription and translation in the rat uterus by ovarian steroid hormones. We examined whether expression of ER alpha mRNA splice isoforms is hormonally regulated in ovariectomized (OVX) and cycling rats. Adult OVX female rats were treated daily with 17-beta estradiol (E2) (0.05 microg/rat or 5 microg/rat), progesterone (P4) (1 mg/rat) or a combination of both hormones for 4 days. Animals were killed 24 h after the last injection and uterine horns were removed. In order to determine whether ER alpha mRNA isoforms are differentially expressed under various physiological conditions, animals were evaluated at proestrus, estrus and diestrus. The ER alpha protein and mRNA were detected by immunohistochemistry and comparative RT-PCR analysis respectively. The presence of ER alpha mRNA isoforms was evaluated using a nested RT-PCR assay. In OVX control rats, ER alpha mRNA and protein levels were high, demonstrating a constitutive expression of the ER alpha gene in the uterus. When animals received P4 or the high dose of E2, a significant decrease in both ER alpha mRNA and protein was observed in the uterus. However, when rats were protein was treated with the low dose of E2, only the ER alpha down-regulated; no changes were observed in ER alpha mRNA expression. In addition to the full-length ER alpha mRNA, OVX control rat uteri expressed three shorter transcripts: sigma3, sigma4 and sigma3,4 (lacking exon 3, exon 4, or both 3 and 4 respectively). Surprisingly, when OVX animals were treated with P4, the low dose of E2 or a combination of both steroids, expression of the sigma3 isoform was completely abolished. During the estrous cycle, all ER alpha mRNA splicing variants were detected at proestrus and estrus. However, in diestrus, significant low levels of the sigma3 isoform were observed. In summary, our results suggest a dose-dependent relationship between E2 concentrations and the level of control in the ER alpha transcription-translation cascade. Moreover, the alternative splicing of the ER alpha primary transcript is influenced by the hormonal milieu, suggesting that these events could affect the estrogen responsiveness of the rat uterus during the estrous cycle.
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Processamento Alternativo , Estradiol/farmacologia , Receptor alfa de Estrogênio/genética , Regulação da Expressão Gênica , Progesterona/farmacologia , Útero/metabolismo , Animais , Relação Dose-Resposta a Droga , Regulação para Baixo , Receptor alfa de Estrogênio/análise , Feminino , Imuno-Histoquímica/métodos , Ovariectomia , Isoformas de Proteínas/análise , Isoformas de Proteínas/genética , RNA Mensageiro/análise , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Útero/química , Útero/efeitos dos fármacosRESUMO
During pregnancy, it is essential that sufficient nutrients are supplied by the vascular system to support the dramatic modifications of the rat uterine cervix. Angiogenesis refers to the growth of new blood vessels from pre-existing microcirculation and mast cells have been associated with this process. This study examined the modifications of the vascular compartment and the distribution of mast cells on cervical tissue during pregnancy. Using disodium cromoglycate as a mast cell stabilizer, we determined the effects of the mast cell degranulation on cervical angiogenesis. Mast cell distribution and their degranulation status were evaluated by immunohistochemistry. Endothelial cell proliferation was measured by bromodeoxyuridine incorporation. Vascular areas (absolute and relative) and maturation indices were assessed by quantitative immunohistochemistry of von Willebrand factor and alpha-smooth muscle actin respectively. Mast cells were predominantly observed during the first half of pregnancy in the perivascular zones. The values of bromodeoxyuridine incorporation, absolute vascular area and vascular maturation index exhibited a significant increase throughout pregnancy. All animals that received mast cell stabilizer showed more than 40% of non-degranulated mast cells. Treated rats exhibited a decrease in endothelial proliferation and in relative vascular area; in addition, a large proportion of mature blood vessels was observed, suggesting a diminished level of new vessel formation. The effects of the mast cell stabilizer were sustained beyond the end of treatment. This is the first report that brings evidence that mast cell degranulation could be a necessary process to contribute to the normal angiogenesis of the rat cervix during pregnancy. Further investigations are needed to elucidate the possible implications of abnormal vascular development of the uterine cervix on the physiological process of ripening and parturition.
Assuntos
Degranulação Celular , Colo do Útero/irrigação sanguínea , Mastócitos/fisiologia , Neovascularização Fisiológica , Prenhez/fisiologia , Animais , Degranulação Celular/efeitos dos fármacos , Divisão Celular , Colo do Útero/citologia , Cromolina Sódica/farmacologia , Células Endoteliais/citologia , Feminino , Imuno-Histoquímica/métodos , Mastócitos/efeitos dos fármacos , Gravidez , Distribuição Aleatória , Ratos , Ratos WistarRESUMO
OBJECTIVE: To determine the effectiveness of transvaginal electrical stimulation (TES) in treating urinary incontinence, and to assess the clinical improvement 6 months after ending the treatment. PATIENTS AND METHODS: In a double-blind randomized controlled clinical trial, 36 women (24 patients and 12 controls) with stress, urge or mixed urinary incontinence were chosen to use TES or placebo (identical equipment but with no electrical current). The patients had their treatment at home twice a day (20-min sessions) for 12 weeks. They completed a voiding diary and had a urodynamic study at the beginning and end of treatment. They were clinically re-evaluated after 6 months. RESULTS: The mean time of use of TES was similar in both groups (approximately 40 h); the treatment group had a significant increase in maximum bladder capacity (P < 0.02), a significant reduction in the total number of voids (over 24 h; P < 0.02), in the number of episodes of voiding urgency (P < 0.001) and, importantly, in the number of episodes of urinary incontinence (P < 0.001). At the first evaluation, after ending the treatment, 88% of the patients had a significant reduction in symptoms or went into remission. At the 6-month re-evaluation, a third of the patients required another therapeutic approach. CONCLUSION: TES is a practical alternative with few side-effects, and is effective for treating the main forms of female urinary incontinence.