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‣ Desenvolvimento e validação de metodologia analítica para determinação de hormônios, considerados disruptores endócrinos, nas águas destinadas ao abastecimento público na região do Rio Paraíba do Sul, SP; Development and validation of analytical methodology for endocrine disruptors hormones determination in water for public supply at region of Paraíba do Sul River, SP

Otomo, Juliana Ikebe
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 12/11/2010 Português
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Os disruptores endócrinos são substâncias químicas, sintéticas ou naturais, capazes de interferir no sistema endócrino de seres humanos e animais. Pertencem à classe dos micro poluentes, pois mesmo em concentrações de μg e ng.L-1 causam efeitos adversos aos organismos a eles expostos. Os hormônios destacam-se dentre os disruptores endócrinos por serem compostos potencialmente ativos no sistema biológico e estão relacionados à origem de diversos tipos de cânceres. Esta dissertação teve por objetivo desenvolver e validar metodologia para determinar hormônios, considerados disruptores endócrinos, em amostras de água bruta e tratada da região da Bacia Hidrográfica do Rio Paraíba do Sul utilizando a técnica de cromatografia gasosa com detecção por espectrometria de massas. A população atendida pelas unidades da SABESP dessa região é de aproximadamente 11 milhões de habitantes. Através do processo de validação, a metodologia desenvolvida pode ser considerada seletiva, robusta, exata, linear e precisa para a análise proposta. Aplicando o procedimento analítico validado nas amostras coletadas, alguns dos compostos estudados puderam ser detectados tanto em água bruta como em água tratada permanecendo abaixo do limite de quantificação...

‣ Efeito do hipertiroidismo experimental, induzido em ratas durante a gestação, sobre componentes do sistema renina-angiotensina cardíaco da prole.; Effect of experimental hyperthyroidism induced in female rats during pregnancy in the components of cardiac Renin-Angiotensin System of the offspring.

Shibata, Caroline Emy Rodrigues
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 25/02/2011 Português
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Durante a gestação normal, o Sistema Renina-Angiotensina (SRA) exerce um papel de importância vital no balanço de sais, pressão sanguínea e homeostase da água e, consequentemente, no bem estar da mãe e do feto. Neste sentido, merece destaque não apenas o SRA clássico (descrito inicialmente como um sistema puramente endócrino), mas também, o SRA local, no caso, útero-placentário, onde nos tecidos materno e fetal os vários componentes do sistema se comportam diferentemente, sob regulação e estímulos locais. As perturbações do SRA útero¬placentário podem ocasionar hemorragias e redução no fluxo sanguíneo entre mãe e feto, podendo levar, como conseqüência, à pré-eclampsia e crescimento intrauterino retardado. Já é bem estabelecido que disfunções da tireóide, como ocorre no hipertiroidismo, promovem amplas alterações no sistema cardiovascular, agindo sobre contratilidade cardíaca, débito cardíaco, pressão sanguínea e resistência vascular sistêmica. Sabe-se ainda que o hipertiroidismo é responsável por importantes alterações sobre o padrão de comportamento dos vários componentes do SRA no indivíduo adulto, e estas, por sua vez, também estão envolvidas com o aparecimento de alterações cardiovasculares. Assim...

‣ Avaliação de desreguladores endócrinos em machos: estudo dos efeitos tóxicos da Ipomoea carnea em caprinos; Evaluation of endocrine disruptors in males: study of toxic effects of Ipomoea carnea in goats

Gotardo, André Tadeu
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 09/09/2013 Português
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Recentemente, pesquisas vêm claramente demonstrando que xenobióticos podem apresentar efeitos deletérios sobre o sistema endócrino e passam a ser de grande importância toxicológica à medida que se tornam contaminantes ambientais. Tais substâncias passaram a ser denominadas de desreguladores endócrinos (DEs). Entre os diferentes DEs identificados, muitos são praguicidas, amplamente utilizados no meio agropecuário em todo o mundo. Atualmente, já são bem estabelecidas as metodologias para avaliação do potencial efeito DE de diferentes substâncias em roedores; porém uma busca na literatura deixa clara a falta de estudos e de protocolos para avaliação de DEs em animais de produção ruminantes, os quais certamente estão expostos a um grande número de agentes tóxicos com estas características. Assim, foi objetivo desta pesquisa dar início ao desenvolvimento de um protocolo para avaliação de efeitos DEs de xenobióticos em ruminantes. Para tal, estudou-se o bisfenol A (BPA), o qual é, classicamente, um DE para roedores. Além disto, avaliou-se o potencial efeito DE da I. carnea, uma planta tóxica de grande importância para ruminantes no Brasil e em outros países. O estudo foi realizado em duas etapas, na primeira avaliou-se os efeitos do BPA e da planta nos caprinos machos púberes; na segunda etapa propôs-se avaliar os efeitos tóxicos da exposição in utero de caprinos machos púberes a estas mesmas substâncias. Os resultados obtidos mostraram que os bodes púberes expostos ao BPA apresentaram redução significante dos níveis séricos de tiroxina...

‣ Quantitative Analysis of Endocrine Disruptors by Comprehensive Two-Dimensional Gas Chromatography

Moreira,Miriany A.; André,Leiliane C.; Ribeiro,Alexandra B.; Silva,Marco D. R. G. da; Cardeal,Zenilda L.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2015 Português
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Comprehensive two-dimensional gas chromatography has been successfully applied to the analysis of various organic contaminants; however, few studies report its use in the analysis of endocrine disrupting compounds. These compounds are suspected to cause dysfunction of the endocrine system in humans and animals. This work describes the development of a method to analyse dibutylphthalate, benzylbutylphthalate, nonylphenol and octylphenol in water using solid-phase microextraction (SPME) and comprehensive two-dimensional gas chromatography with a flame ionisation detector. The merit parameters of the comprehensive two-dimensional gas chromatography with flame ionisation detector method were weighed against a gas chromatography/mass spectrometry-single ion monitoring method of endocrine disrupting compounds analysis. The compounds were evaluated over a concentration range of 0.2 to 6.0 µg L-1 . The use of a two-dimensional chromatography method proved to be advantageous in analysing endocrine disrupting compounds, according to the observed increase of the signal relative to the noise and peak resolution.

‣ Evidence for alteration of the vitamin D-endocrine system in obese subjects.

Bell, N H; Epstein, S; Greene, A; Shary, J; Oexmann, M J; Shaw, S
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/1985 Português
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Serum immunoreactive parathyroid hormone (PTH) is increased in obese as compared with nonobese subjects and declines with weight loss. To determine whether alteration of the vitamin D-endocrine system occurs in obesity and whether ensuing secondary hyperparathyroidism is associated with a reduction in urinary calcium, a study was performed in 12 obese white individuals, five men and seven women, and 14 nonobese white subjects, eight men and six women, ranging in age from 20 to 35 yr. Body weight averaged 106 +/- 6 kg in the obese and 68 +/- 2 kg in the nonobese subjects (P less than 0.01). Each of them were hospitalized on a metabolic ward and were given a constant daily diet containing 400 mg of calcium and 900 mg of phosphorus. Whereas mean serum calcium, serum ionized calcium, and serum phosphorus were the same in the two groups, mean serum immunoreactive PTH (518 +/- 48 vs. 243 +/- 33 pg/ml, P less than 0.001), mean serum 1,25-dihydroxyvitamin D [1,25(OH)2D] (37 +/- 2 vs. 29 +/- 2, P less than 0.01), and mean serum Gla protein (33 +/- 2 vs. 24 +/- 2 ng/ml, P less than 0.02) were significantly higher, and mean serum 25-hydroxyvitamin D (25-OHD) (8 +/- 1 vs. 20 +/- 2 ng/ml, P less than 0.001) was significantly lower in the obese than in the nonobese men and women. Mean urinary phosphorus was the same in the two groups...

‣ Evidence for alteration of the vitamin D-endocrine system in blacks.

Bell, N H; Greene, A; Epstein, S; Oexmann, M J; Shaw, S; Shary, J
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/1985 Português
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As compared with values in white subjects, bone mass is known to be increased and urinary calcium to be diminished in black individuals. To evaluate the possibility that these changes are associated with alterations in the vitamin D-endocrine system, an investigation was performed in 12 black subjects, 7 men and 5 women, and 14 white subjects, 8 men and 6 women, ranging in age from 20 to 35 yr. All of them were hospitalized on a metabolic ward and were given a constant daily diet containing 400 mg of calcium, 900 mg of phosphorus, and 110 meq of sodium. Whereas mean serum calcium, ionized calcium, and phosphate were the same in the two groups, mean serum immunoreactive parathyroid hormone (350 +/- 34 vs. 225 +/- 26 pg/ml, P less than 0.01) and mean serum 1,25-dihydroxyvitamin D (1,25(OH)2D) (41 +/- 3 vs. 29 +/- 2 pg/ml, P less than 0.01) were significantly higher, and mean serum 25-hydroxy-vitamin D (25-OHD) was significantly lower in the blacks than in the whites (6 +/- 1 vs. 20 +/- 2 ng/ml, P less than 0.001). Mean urinary sodium and 24-h creatinine clearance were the same in the two groups, whereas mean urinary calcium was significantly lower (101 +/- 14 vs. 166 +/- 13 mg/d, P less than 0.01) and mean urinary cyclic AMP was significantly higher (3.11 +/- 0.47 vs. 1.84 +/- 0.25 nM/dl glomerular filtrate...

‣ Proliferative activity of neuroendocrine tumours of the gastroenteropancreatic endocrine system: DNA flow cytometric and immunohistological investigations.

von Herbay, A; Sieg, B; Schürmann, G; Hofmann, W J; Betzler, M; Otto, H F
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/1991 Português
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The proliferative activity of 16 tumour specimens from 13 patients with neuroendocrine tumours of the gastroenteropancreatic endocrine system was studied by DNA flow cytometry and immunohistology for the nuclear Ki67 proliferation antigen. Equivalent results were obtained with both methods, which showed the proliferative activity of gastroenteropancreatic neuroendocrine tumours to be heterogeneous. In four malignant small intestinal carcinoids and one extravisceral carcinoid localised in the retroperitoneum the percentage (index) of proliferating tumour cells as measured by DNA flow cytometry ranged from 2.9 to 36.2% corresponding to low, moderate, or high proliferative activity. In four malignant pancreatic endocrine tumours and their metastases indices ranged from 8.7 to 18.3%, corresponding to low, moderate, or high proliferative activity. In four benign pancreatic endocrine tumours indices ranged from 4.3 to 7.7%, all corresponding to low proliferative activity. This heterogeneity of proliferative activity may in part explain the heterogeneous results reported of chemotherapy treatment. As chemotherapy of tumours is largely affected by favourable cell cycling kinetics, individual diagnostic investigations of the proliferative activity of these neuroendocrine tumours may be of value for identifying patients suitable for this treatment.

‣ From the bench to emerging new clinical concepts: Our present understanding of the importance of the vitamin D endocrine system (VDES) for skin cancer

Trémezaygues, Léa; Reichrath, Jörg
Fonte: Landes Bioscience Publicador: Landes Bioscience
Tipo: Artigo de Revista Científica
Publicado em //2011 Português
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It is well accepted that growth and differentiation of keratinocytes and other cell types are regulated by 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], the active form of vitamin D. Moreover, growing evidence now indicates that the UV-B-mediated cutaneous photosynthesis of vitamin D [and the consecutive cutaneous production of 1,25(OH)2D3)] represents an evolutionary highly-conserved endocrine system that protects the skin against environmental hazards that may promote skin cancerogenesis, including ultraviolet and ionizing radiation. It is the aim of this review to summarize our present understanding of the cutaneous vitamin D endocrine system (VDES) and its importance for the prevention of skin cancerogenesis.

‣ Hypothalamic-Pituitary-Gonadal Endocrine System in the Hagfish

Nozaki, Masumi
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Publicado em 30/12/2013 Português
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The hypothalamic-pituitary system is considered to be a seminal event that emerged prior to or during the differentiation of the ancestral agnathans (jawless vertebrates). Hagfishes as one of the only two extant members of the class of agnathans are considered the most primitive vertebrates known, living or extinct. Accordingly, studies on their reproduction are important for understanding the evolution and phylogenetic aspects of the vertebrate reproductive endocrine system. In gnathostomes (jawed vertebrates), the hormones of the hypothalamus and pituitary have been extensively studied and shown to have well-defined roles in the control of reproduction. In hagfish, it was thought that they did not have the same neuroendocrine control of reproduction as gnathostomes, since it was not clear whether the hagfish pituitary gland contained tropic hormones of any kind. This review highlights the recent findings of the hypothalamic-pituitary-gonadal endocrine system in the hagfish. In contrast to gnathostomes that have two gonadotropins (GTH: luteinizing hormone and follicle-stimulating hormone), only one pituitary GTH has been identified in the hagfish. Immunohistochemical and functional studies confirmed that this hagfish GTH was significantly correlated with the developmental stages of the gonads and showed the presence of a steroid (estradiol) feedback system at the hypothalamic-pituitary levels. Moreover...

‣ Immunohistochemical Localization of Huntingtin-associated Protein 1 in Endocrine System of the Rat

Liao, Min; Shen, Jianying; Zhang, Yinong; Li, Shi-Hua; Li, Xiao-Jiang; Li, He
Fonte: SAGE Publications Publicador: SAGE Publications
Tipo: Artigo de Revista Científica
Publicado em /12/2005 Português
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Huntingtin-associated protein 1 (HAP1) was originally found to be localized in neurons and is thought to play an important role in neuronal vesicular trafficking and/or organelle transport. Based on functional similarity between neuron and endocrine cell in vesicular trafficking, we examined the expression and localization of HAP1 in the rat endocrine system using immunohistochemistry. HAP1-immunoreactive cells are widely distributed in the anterior lobe of the pituitary, scattered in the wall of the thyroid follicles, or clustered in the interfollicular space of the thyroid gland, exclusively but diffusely distributed in the medullae of adrenal glands, and selectively located in the pancreas islets. HAP1-containing cells were also found in the mucosa of stomach and small intestine with a distributive pattern similar to that of gastrointestinal endocrine cells. However, no HAP1-immunoreactive cell was found in the cortex of the adrenal gland, the testis, and the ovary. In the posterior lobe of the pituitary, HAP1-immunoreactive products were not detected in the cell bodies but in many stigmoid bodies, one kind of non-membrane-bound cytoplasmic organelle with a central or eccentric electron-lucent core. HAP1-immunoreactive stigmoid bodies were also found in the cytoplasm of endocrine cells in the thyroid gland...

‣ Long non-coding RNAs as regulators of the endocrine system

Knoll, Marko; Lodish, Harvey F.; Sun, Lei
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Português
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Long non-coding RNAs (lncRNAs) are a large and diverse group of RNAs that are often lineage-specific and that regulate multiple biological functions. Many are nuclear and are essential parts of ribonucleoprotein complexes that modify chromatin segments and establish active or repressive chromatin states; others are cytosolic and regulate the stability of mRNA or act as microRNA sponges. This Review summarizes the current knowledge of lncRNAs as regulators of the endocrine system, with a focus on the identification and mode of action of several endocrine-important lncRNAs. We highlight lncRNAs that have a role in the development and function of pancreatic β cells, white and brown adipose tissue, and other endocrine organs, and discuss the involvement of these molecules in endocrine dysfunction (for example, diabetes mellitus). We also address the associations of lncRNAs with nuclear receptors involved in major hormonal signalling pathways, such as estrogen and androgen receptors, and the relevance of these associations in certain endocrine cancers.

‣ Possible Involvement of Photoperiodic Regulation in Reproductive Endocrine System of Female Olive Flounder Paralichthys olivaceus

Kim, Hyun Chul; Lee, Chi Hoon; Hur, Sung Pyu; Kim, Byeong Hoon; Park, Jun Young; Lee, Young Don
Fonte: Korean Society of Developmental Biology Publicador: Korean Society of Developmental Biology
Tipo: Artigo de Revista Científica
Publicado em /03/2015 Português
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This study investigated possible involvement of photoperiodic regulation in reproductive endocrine system of female olive flounder. To investigate the influence on brain-pituitary axis in endocrine system by regulating photoperiod, compared expression level of Kisspeptin and sbGnRH mRNA in brain and FSH-β, LH-β and GH mRNA in pituitary before and after spawning. Photoperiod was treated natural photoperiod and long photoperiod (15L:9D) conditions from Aug. 2013 to Jun. 2014. Continuous long photoperiod treatment from Aug. (post-spawning phase) was inhibited gonadal development of female olive flounder. In natural photoperiod group, the Kiss2 expression level a significant declined in Mar. (spawning period). And also, FSH-β, LH-β and GH mRNA expression levels were increasing at this period. However, in long photoperiod group, hypothalamic Kiss2, FSH-β, LH-β and GH mRNA expression levels did not show any significant fluctuation. These results suggest that expression of hypothalamic Kiss2, GtH and GH in the pituitary would change in response to photoperiod and their possible involvement of photoperiodic regulation in reproductive endocrine system of the BPG axis.

‣ Endocrine Disruption Research: Final Report. Exploring novel endpoints, exposure, low-dose and mixture effects in humans, aquatic wildlife and laboratory animals

Kortenkamp, Andreas; Pottinger, Thomas; Sharpe, Richard; Skakkeb??k, Niels; Toppari, Jorma; Gerritsen, Anton; Sumpter, John; Mayer, Ian; Olea, Nicol??s; Vartiainen, Terttu; Eggen, Rik I. L.; Vermeulen, Nico; Hock, Bertold; Jegou, Bernard; Segner, Helmut;
Fonte: EDEN (Endocrine Disruption Research) Project Publicador: EDEN (Endocrine Disruption Research) Project
Tipo: Relatório
Português
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The EDEN project is an interdisciplinary effort conceived to address key issues that have hampered sound hazard and risk assessment for endocrine disrupting chemicals (EDCs) in the European Union. It has adopted an approach that fully integrates human, wildlife, exposures, mechanisms and low-dose/mixture evaluations. The project was structured into four interlocking themes focusing on EDC mixture exposures, mechanisms of action and novel endpoints, effects on male reproductive health and the evaluation of low-dose and mixture effects of EDCs. For the first time, the simultaneous occurrence of nearly 150 different EDCs in human and wildlife tissues was measured. These studies revealed that numerous EDCs occur together in humans, yet differences in the levels of individual EDCs in specimens from boys with cryptorchidism and from women suffering from breast cancer and their respective controls did not become apparent. It appears that the likelihood of developing any of the above conditions cannot be attributed to any individual chemical at relevant exposure levels. However, there are signs that simultaneous exposure to many different EDCs may play a cumulative role in these disease processes. This means that efforts to develop biomarkers of cumulative EDC exposure should be re-doubled. In contrast...

‣ Exposici??n humana a compuestos con actividad disruptora endocrina en la poblaci??n espa??ola

Arrebola Moreno, Juan Pedro; Fern??ndez, Mariana F.; Molina-Molina, Jos??-Manuel; Freire Warden, Carmen; Fern??ndez, M.; Amaya, E.; Ramos, R.; Navea, N.; S??enz, J.M.; Oc??n-Hern??ndez, Olga; Calvente, Irene; Olea, Nicol??s
Fonte: Universidad de Granada, Facultad de Farmacia Publicador: Universidad de Granada, Facultad de Farmacia
Tipo: Artigo de Revista Científica
Português
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Introducci??n: En el concepto de disruptor endocrino se incluye un amplio grupo de compuestos qu??micos, con diversas estructuras moleculares, que comparten su capacidad de interferir sobre el sistema hormonal. Los disruptores endocrinos est??n presentes en ??tiles y elementos de uso cotidiano, desde pl??sticos, papel reciclado a plaguicidas y cosm??ticos. Numerosos estudios han demostrado efectos adversos sobre la salud humana derivados de la exposici??n a disruptores endocrinos, como alteraciones reproductivas y aumento de ciertos tipos de c??ncer. Objetivo: Recopilar informaci??n acerca del grado de exposici??n de la poblaci??n general espa??ola a disruptores endocrinos. Metodolog??a: Revisi??n sistem??tica de todas las publicaciones cient??ficas de los ??ltimos 5 a??os acerca de exposici??n humana a disruptores endocrinos, en muestras de poblaci??n general espa??ola. Discusi??n: De la revisi??n realizada se deduce que la poblaci??n espa??ola est?? expuesta de forma frecuente a disruptores endocrinos, ya que se encuentran niveles detectables de estos compuestos en diferentes matrices biol??gicas de diversos grupos de poblaci??n. La progresiva incorporaci??n de nuevas sustancias en el mercado, as?? como la falta de estudios cient??ficos que eval??en la incertidumbre en torno al efecto combinado de m??ltiples residuos...

‣ The Effects of Opioids and Opioid Analogs on Animal and Human Endocrine Systems

Vuong, Cassidy; Van Uum, Stan H. M.; O'Dell, Laura E.; Lutfy, Kabirullah; Friedman, Theodore C.
Fonte: The Endocrine Society Publicador: The Endocrine Society
Tipo: Artigo de Revista Científica
Português
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Opioid abuse has increased in the last decade, primarily as a result of increased access to prescription opioids. Physicians are also increasingly administering opioid analgesics for noncancer chronic pain. Thus, knowledge of the long-term consequences of opioid use/abuse has important implications for fully evaluating the clinical usefulness of opioid medications. Many studies have examined the effect of opioids on the endocrine system; however, a systematic review of the endocrine actions of opioids in both humans and animals has, to our knowledge, not been published since 1984. Thus, we reviewed the literature on the effect of opioids on the endocrine system. We included both acute and chronic effects of opioids, with the majority of the studies done on the acute effects although chronic effects are more physiologically relevant. In humans and laboratory animals, opioids generally increase GH and prolactin and decrease LH, testosterone, estradiol, and oxytocin. In humans, opioids increase TSH, whereas in rodents, TSH is decreased. In both rodents and humans, the reports of effects of opioids on arginine vasopressin and ACTH are conflicting. Opioids act preferentially at different receptor sites leading to stimulatory or inhibitory effects on hormone release. Increasing opioid abuse primarily leads to hypogonadism but may also affect the secretion of other pituitary hormones. The potential consequences of hypogonadism include decreased libido and erectile dysfunction in men...

‣ Occupational exposure and effects on the male reproductive system

Queiroz,Erika Kaltenecker Retto de; Waissmann,William
Fonte: Escola Nacional de Saúde Pública Sergio Arouca, Fundação Oswaldo Cruz Publicador: Escola Nacional de Saúde Pública Sergio Arouca, Fundação Oswaldo Cruz
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2006 Português
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A significant increase in the incidence of male infertility has been described in the international literature, raising questions about its causes. Part of this effect may result from synthetic toxic substances acting on the endocrine system (endocrine disruptors), many of which are routinely used in work processes. We provide a critical review of the specialized literature on work-related chemical substances capable of causing male infertility. Pesticides such as DDT, linuron, and others, heavy metals like mercury, lead, cadmium, and copper, and substances from various industrial uses and residues such as dioxins, polychlorinated biphenyls (PCBs), ethylene dibromide (EDB), phthalates, polyvinyl chloride (PVC), and ethanol are among the main endocrine disruptors that can cause male infertility. Based on the literature, gonadal dysfunction and congenital malformation are the main alterations caused by these substances in the male reproductive system. We conclude that despite the relative lack of studies on this issue, the relevance of such risk calls for further studies as well as measures to prevent workers' exposure to the various substances.

‣ A characterization of selected endocrine disruptor compounds in a Portuguese wastewater treatment plant

Maurício, R.; Diniz, Mario S.; Petrovic, Mira; Almaral, L.; Peres, I.; Barceló, Damià; Santana, F.
Fonte: Springer Publicador: Springer
Tipo: Artículo Formato: 19968 bytes; application/msword
Português
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13 pages, 6 tables, 2 figures.-- PMID: 16897535 [PubMed].; Anthropogenic compounds that are able to disrupt the endocrine system of wildlife species are a major cause for concern and have led to a demand for new screening methods. The identification and quantification of endocrine disruptor compounds at wastewater treatment plant is of major interest to assess the endocrine activity of wastewater treatment plant discharges into the environment. This study consists of a preliminary survey of concentrations of previously selected endocrine disruptor compounds, undertaken to establish environmental concentrations and to support a biological program assay exposing freshwater fish to them. Selected endocrine disrupting chemicals (APEs, bisphenol A and 17 β-estradiol) were measured in samples from a wastewater treatment plant located in Lisbon (Portugal), using recent commercial enzyme-linked immunosorbent assay kits and also LC-MS/MS. The results show that the wastewater treatment plant treatment process is efficient on the removal of target endocrine disruptor compounds. However, environmentally significant concentrations are still present in the treated effluent. The results also show that enzyme-linked immunosorbent assay kit is suitable for routine analysis of the selected compounds. The results are also useful since the wastewater treatment plant is located in a Mediterranean region...

‣ Review: the role of neural crest cells in the endocrine system

Adams, Meghan Sara; Bronner, Marianne E.
Fonte: Humana Press Publicador: Humana Press
Tipo: Article; PeerReviewed Formato: application/pdf
Publicado em /06/2009 Português
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The neural crest is a pluripotent population of cells that arises at the junction of the neural tube and the dorsal ectoderm. These highly migratory cells form diverse derivatives including neurons and glia of the sensory, sympathetic, and enteric nervous systems, melanocytes, and the bones, cartilage, and connective tissues of the face. The neural crest has long been associated with the endocrine system, although not always correctly. According to current understanding, neural crest cells give rise to the chromaffin cells of the adrenal medulla, chief cells of the extra-adrenal paraganglia, and thyroid C cells. The endocrine tumors that correspond to these cell types are pheochromocytomas, extra-adrenal paragangliomas, and medullary thyroid carcinomas. Although controversies concerning embryological origin appear to have mostly been resolved, questions persist concerning the pathobiology of each tumor type and its basis in neural crest embryology. Here we present a brief history of the work on neural crest development, both in general and in application to the endocrine system. In particular, we present findings related to the plasticity and pluripotency of neural crest cells as well as a discussion of several different neural crest tumors in the endocrine system.

‣ RITMOS HORMONAIS DO PÂNCREAS ENDÓCRINO: DOS FUNDAMENTOS CRONOBIOLÓGICOS ÀS IMPLICAÇÕES CLÍNICAS; HORMONE RHYTHMS OF THE ENDOCRINE PANCREAS: FROM THE CHRONOBIOLOGICAL FUNDAMENTALS TO THE CLINICAL IMPLICATIONS

Delattre, Edson
Fonte: Universidade de São Paulo. Faculdade de Medicina de Ribeirão Preto Publicador: Universidade de São Paulo. Faculdade de Medicina de Ribeirão Preto
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf
Publicado em 30/06/2004 Português
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Inicialmente, são apresentadas as bases teóricas para o conhecimento dos ritmos endócrinos, considerando-se que, virtualmente, todas as secreções hormonais apresentam acentuadas oscilações, o que demonstra um alto grau de organização temporal do sistema endócrino. A seguir, o trabalho revisa a ritmicidade do pâncreas endócrino, ressaltando os ritmos circadianos e ultradianos da insulina, em razão de sua importância para a fisiologia e fisiopatologia desse órgão. São apresentados tanto os resultados obtidos in vitro, quanto aqueles verificados clinicamente. Discutem-se as razões biológicas para a secreção pulsátil dos hormônios em geral, bem como as alterações desse ritmo em patologias do pâncreas endócrino.; Initially the theoretical basis for the knowledge of the endocrine rhythms are presented, by taking into consideration that all hormonal secretions display stressed oscillations that denotes a high degree of temporal organization in the endocrine system. Next, the work reviews the rhythm of the endocrine pancreas, by pointing out the circadian and ultradian rhythms of insulin, due to its importance for the physiology and physiopathology of that organ. Both the results secured in vitro and those noticed clinically are presented. The biological reasons for the pulsatile hormones secretion in general are discussed as well as changes of that rhythm...

‣ Occupational exposure and effects on the male reproductive system

Queiroz,Erika Kaltenecker Retto de; Waissmann,William
Fonte: Escola Nacional de Saúde Pública Sergio Arouca, Fundação Oswaldo Cruz Publicador: Escola Nacional de Saúde Pública Sergio Arouca, Fundação Oswaldo Cruz
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2006 Português
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A significant increase in the incidence of male infertility has been described in the international literature, raising questions about its causes. Part of this effect may result from synthetic toxic substances acting on the endocrine system (endocrine disruptors), many of which are routinely used in work processes. We provide a critical review of the specialized literature on work-related chemical substances capable of causing male infertility. Pesticides such as DDT, linuron, and others, heavy metals like mercury, lead, cadmium, and copper, and substances from various industrial uses and residues such as dioxins, polychlorinated biphenyls (PCBs), ethylene dibromide (EDB), phthalates, polyvinyl chloride (PVC), and ethanol are among the main endocrine disruptors that can cause male infertility. Based on the literature, gonadal dysfunction and congenital malformation are the main alterations caused by these substances in the male reproductive system. We conclude that despite the relative lack of studies on this issue, the relevance of such risk calls for further studies as well as measures to prevent workers' exposure to the various substances.