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1.
Rev Bras Med Trab ; 20(2): 178-184, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36127904

RESUMO

Introduction: Different forms of rationalization are introduced through work, which result from economic, political, and social changes that increase the need for labor force. Within this context, there are institutions that neglect the effects of poor work environments on workers' health, such as the development of work-related mental and psychological disorders. Objectives: To understand what it means to work as an official expert at a forensic medicine institute and investigate occupational and workplace factors that may contribute to emotional and psychological stress and/or depression. Methods: We conducted an exploratory, qualitative study at a forensic medicine institute of a Brazilian capital city. Data were collected using semi-structured interviews with study participants, which were selected according to inclusion and exclusion criteria. Results: Occupational factors, including physical organization and psychological demand, may generate or contribute to the development of psychological and emotional stress and/or depression in forensic medicine workers. Working conditions are related to the quality and quantitative performance of the worker and influence whether worker productivity meets the demands of those using the services provided by the institute. Conclusions: This study revealed the reality of those working at a forensic medicine institute and identified possible factors that may cause emotional instability, psychological and emotional stress, and/or depression. We identified the need for changes in the workplace and the creation of social policies focused on mental health to minimize occupational illness.

2.
Surg. cosmet. dermatol. (Impr.) ; 4(2): 114-120, Abr.-Jun. 2012. ilus.
Artigo em Inglês, Português | LILACS | ID: biblio-879476

RESUMO

Introdução: Melasma é hiperpigmentação adquirida que afeta primariamente a face, e acomete mais comumente mulheres de pele escura. Diversas são as terapias utilizadas para seu tratamento; seu manejo clínico a longo prazo, entretanto, permanece um desafio. Objetivos: Avaliar a eficácia do laser de érbio: YAG fracionado, analisar histologicamente as características usuais do melasma e a quantidade de pigmento na epiderme e derme antes e após o tratamento. Métodos: Dez pacientes foram submetidas a três sessões do laser de érbio: YAG fracionado ablativo com intervalo de um mês de uma para outra. As pacientes foram biopsiadas antes e após o tratamento. Foram realizadas avaliações clínicas subjetivas e objetivas, antes, durante e após o tratamento. Resultados: Não foi observada melhora do escore Masi ao longo do tratamento. Histologicamente foram observadas hiperpigmentação da camada basal e deposição de pigmento em derme superficial. Em sete casos observou-se redução no grau de hiperpigmentação da epiderme, sem significância estatística. Conclusões: O tratamento do melasma com o laser de érbio: YAG fracionado ablativo não se mostrou efetivo, apesar de haver tendência a diminuição dos escore Masi e no grau de hiperpigmentação da epiderme, sugerindo que o laser de érbio: YAG pode ser capaz de melhorar tanto clínica quanto histologicamente o grau de hiperpigmentação da pele.


Introduction: Melasma is an acquired hyperpigmentation that affects primarily the face and occurs more frequently in women with darker skin. There are several therapies for treating melasma, however its longterm management remains a challenge. Objectives: To evaluate fractional Erbium:YAG laser's clinical effectiveness in treating refractory melasma through the histological analysis of usual characteristics and the amount of epidermal and dermal pigment before and after treatment. Methods: Ten patients underwent three fractional Erbium:YAG laser sessions at monthly intervals. Biopsies were obtained before and after treatment. Subjective and objective clinical evaluations were carried out before, during, and after treatment. Results: No statistical improvement in Melasma Area Severity Index score was observed during the treatment. Hyperpigmentation of the basal layer and pigment deposition in the dermis was observed histologically. In seven cases, there was a reduction in the degree of hyperpigmentation in the epidermis, which was not statistically significant. Conclusions: The treatment of melasma with fractional Erbium:YAG laser was ineffective. Nonetheless, a decrease in Melasma Area Severity Index scores and in the degree of hyperpigmentation of the epidermis was detected, suggesting that fractional Erbium:YAG laser can clinically and histologically improve the degree of hyperpigmentation of the skin.

3.
An Bras Dermatol ; 86(4 Suppl 1): S17-20, 2011.
Artigo em Inglês, Português | MEDLINE | ID: mdl-22068761

RESUMO

Erosive adenomatosis of the nipple is a complex benign mammary proliferation that can be misdiagnosed as a malignant mammary neoplasm. The most common clinical presentation includes discharge, erythema, erosion and crusting. The process is usually asymptomatic. It resembles benign conditions such as contact dermatitis, psoriasis and infections, but its main differential diagnosis is Paget's disease. Treatment is usually surgical and the prognosis is excellent.


Assuntos
Adenoma/patologia , Neoplasias da Mama/patologia , Mamilos/patologia , Adenoma/cirurgia , Adulto , Neoplasias da Mama/cirurgia , Feminino , Humanos , Mamilos/cirurgia
4.
An. bras. dermatol ; 86(4,supl.1): 17-20, jul,-ago. 2011. ilus
Artigo em Português | LILACS | ID: lil-604110

RESUMO

A adenomatose erosiva do mamilo é uma complexa proliferação benigna mamária que pode ser confundida com neoplasias malignas da mama. A apresentação típica cursa com descarga mamária, eritema, erosão e formação de crostas. O processo é geralmente assintomático e de instalação insidiosa. A adenomatose erosiva do mamilo pode ser confundida com condições benignas, como a dermatite de contato, psoríase e infecções, mas seu principal diagnóstico diferencial é a Doença de Paget. O tratamento é cirúrgico e o prognóstico, excelente.


Erosive adenomatosis of the nipple is a complex benign mammary proliferation that can be misdiagnosed as a malignant mammary neoplasm. The most common clinical presentation includes discharge, erythema, erosion and crusting. The process is usually asymptomatic. It resembles benign conditions such as contact dermatitis, psoriasis and infections, but its main differential diagnosis is Paget's disease. Treatment is usually surgical and the prognosis is excellent.


Assuntos
Adulto , Feminino , Humanos , Adenoma/patologia , Neoplasias da Mama/patologia , Mamilos/patologia , Adenoma/cirurgia , Neoplasias da Mama/cirurgia , Mamilos/cirurgia
5.
Brain Res ; 1070(1): 15-23, 2006 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-16405927

RESUMO

Opioid peptides exert an inhibitory effect on hypothalamic gonadotropin releasing hormone (GnRH) secretion mainly by interacting with mu-opioid receptors. Although a direct role for opioids via delta-opioid receptors (DORs) has been suggested, the presence of these receptors on GnRH neurons has never been demonstrated. In the present study, we determined the distribution of DORs in the basal hypothalamus of rat with special focus on their relation to GnRH neurons. Double-labelling immunofluorescence and confocal microscopy revealed that DORs are exclusively present in a subpopulation of GnRH nerve terminals, with the highest density in the external layer of the median eminence. We then studied the functional characteristics of DORs in an immortalized GnRH-secreting neuronal cell line (GT1-1) known to endogenously express this receptor. Here, pertussis toxin pretreatment abolished the delta-agonist (DPDPE) inhibitory effect on cAMP accumulation. We also analyzed the type of G proteins involved in the signal transduced by the DOR and showed that GT1-1 cells express the inhibitory Go and Gi2 alpha-subunits. However, only Go was down-regulated under chronic DPDPE exposure. Finally, since DOR is expressed postnatally in brain, we compared GnRH neuronal cells immortalized at different developmental stages (the more mature GT1-1 and GT1-7 cells, versus the more immature GN11 cells), evidencing that only mature neurons express DOR. In conclusion, our study indicates that a direct control of opioids via delta-receptors occurs on GnRH neurons and validates the use of GT1 cells to further investigate the nature of the DOR present on GnRH neurons.


Assuntos
Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo/metabolismo , Neurônios/metabolismo , Receptores Opioides delta/metabolismo , Animais , Linhagem Celular Transformada , Senescência Celular , AMP Cíclico/antagonistas & inibidores , Regulação para Baixo , D-Penicilina (2,5)-Encefalina/farmacologia , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Hipotálamo/citologia , Hipotálamo Médio/citologia , Hipotálamo Médio/metabolismo , Terminações Nervosas/metabolismo , Neurônios/fisiologia , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
6.
Brasília méd ; 43(1/4): 40-47, 2006.
Artigo em Português | LILACS | ID: lil-566737

RESUMO

O estudo dos neurônios que produzem o hormônio liberador das gonadotrofinas (GnRH), hormônio hipotalámico que estimula a secreção, das gonadotrofinas hipofisárias, tem recebido vigoroso impulso com a disponibilidade das células imortalizadas, que especificamente sintetizam e secretam o hormônio em questão. Duas são as linhas celulares obtidas por tumorigênese induzida em camundongos transgênicos: 1) as células GT1 (com os seus subclones GT1-1, GT1-3, GT1-7) e 2) as células GN (com os seus subclones GN10, GN11, NLT). As células GT1 foram derivadas de um tumor hipotalâmico. Pode-se constatar que elas são dotadas de propriedades dos neurônios maduros secretores de GnRH, que completaram o seu trajeto da sua sede de origem, o placóide olfatório, até a sua sede definitiva, o hipotálamo, e já perderam a capacidade de mover-se. Por essas características, as células GT1 são utilizadas sobretudo para o estudo das propriedades secretórias dos neurônios que produzem o GnRH e para identificar os sinais que ali chegam. Pode-se assim evidenciar uma série de receptores, que, ativados pelos seus ligantes (neurotransmissores, hormônios, fatores de crescimento), modulam a síntese e a secreção do GnRH. As células GN foram retiradas de um tumor do bulbo olfatório, portanto, elas são consideradas mais semelhantes aos neurônios imaturos secretores de GnRH que ainda estão desenvolvendo o processo de migração do placóide olfatório até o hipotálamo. Desse modo, tais células são utilizadas sobretudo para identificar e caracterizar os fatores que possam influenciar os processos de migração dos neurônios que produzem o GnRH. Em particular, pode-se constatar que a motilidade dos neurônios secretores desse hormônio é estimulada pela anosmina, a proteína codificada pelo gene KAL1, que, nas suas formas mutantes, ocasiona o hipogonadismo hipogonadotrófico conhecido como a síndrome de Kallmann, por alguns fatores de crescimento (fator de crescimento de fibroblasto, fator de crescimento...


The study of the neurons secreting the gonadotropin releasing hormone (GnRH), the hypothalamic hormone stimulating the release of pituitary gonadotropins, has been potentiated by the development of immortalized cells that specifically synthetize and secrete GnRH. Two cell lines have been obtained by targeted tumorigenesis in transgenic mice: 1) the GT1 cells (with GT1-1, GT1-3 and GT1-7 subclones), and 2) the GN cells (with the GN10, GN11 and NLT subclones). GT1 cells have been obtained from a hypothalamic tumor and exhibit the properties of fully mature GnRH secreting neurons after they reached their final destination in the hypothalamus starting from the olfactory placode. Because of their characteristics GT1 cells have been mainly utilized to investigate the secretory properties of GnRH neurons and to identify the inputs modulating their activity. By this way a consistent number of receptors responding to specific ligands (neurotransmitters, hormones, growth factors) controlling GnRH synthesis and secretion has been identified. GN cells have been derived from a tumor of the olfactory bulb and are considered to replicate the properties of immature GnRH secreting neurons still retaining the capacity of moving. Consequently these cells are used to identify and characterize the factors influencing the migratory process of GnRH neurons from the olfactory placode to the hypothalamus. It has been found that factors stimulating GnRH neuron motility include anosmin, the protein encoded by the KAL1 gene, whose mutations lead to the form of hypogonadotropic hypogonadism known as Kallmann’s syndrome, growth factors such as fibroblast growth factor, hepatocyte growth factor, vascular endothelial growth factor, and cytoskeleton associated proteins (stathmin). On the contrary GABA agonists and glucocorticoids depress GN cells motility. As a whole the findings reported in this review seem particularly important to provide further information on the central...


Assuntos
Humanos , Gonadotropinas Hipofisárias , Hipotálamo , Hormônio Liberador de Gonadotropina , Hormônios Hipofisários , Hormônios Liberadores de Hormônios Hipofisários , Receptores LHRH , Síndrome de Kallmann
7.
Neuroendocrinology ; 82(3-4): 151-63, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16498266

RESUMO

Prenatal exposure of rodents to glucocorticoids (Gc) affects the sexual development of the offspring, possibly interfering with the differentiation of the hypothalamic-pituitary-gonadal axis. Glucocorticoid receptors (GR) are present on gonadotropin-releasing hormone (GnRH) neurons in the rat hypothalamus, suggesting a direct effect of Gc in the control of the synthesis and/or release of the hormone. In this study, we demonstrate the colocalization of immunoreactive GR with GnRH in a subpopulation of mouse hypothalamic GnRH neurons, confirming the possible involvement of Gc in mouse GnRH neuronal physiology. Receptor-binding assay, RT-PCR, immunocytochemistry, and immunoblotting experiments carried out in GN11 immortalized GnRH neurons show the presence of GR even in the more immature mouse GnRH neurons and confirm the expression of GR in GT1-7 mature GnRH cells. In GN11 cells, the activation of GR with dexamethasone produces nuclear translocation, but does not lead to the inhibition of GnRH gene expression already reported in GT1-7 cells. Long-term exposure of GN11 cells to dexamethasone induces an epithelial-like phenotype with a reorganization of F-actin in stress fibers. Finally, we found that Gc treatment significantly decreases the migratory activity in vitro and the levels of phosphorylated focal adhesion kinase of GN11 immature neurons. In conclusion, these data indicate that GR are expressed in mouse hypothalamic GnRH neurons in vivo as well as in the immature GN11 GnRH neurons in vitro. Moreover, the effects of the GR activation in GN11 and in GT1-7 cells may be related to the neuronal maturational stage of the two cell lines, suggesting a differential role of Gc in neuronal development.


Assuntos
Hormônio Liberador de Gonadotropina/metabolismo , Neurônios/metabolismo , Receptores de Glucocorticoides/metabolismo , Fatores Etários , Animais , Northern Blotting , Células Cultivadas , Dexametasona/farmacologia , Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , Hormônio Liberador de Gonadotropina/efeitos dos fármacos , Hipotálamo/crescimento & desenvolvimento , Hipotálamo/metabolismo , Imuno-Histoquímica , Masculino , Camundongos , Neurônios/efeitos dos fármacos , Receptores de Glucocorticoides/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Hum Mol Genet ; 13(22): 2781-91, 2004 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-15471890

RESUMO

X-linked Kallmann's syndrome (KS) is a genetic disease characterized by anosmia and hypogonadism due to impairment in the development of olfactory axons and in the migration of gonadotropin-releasing hormone (GnRH)-producing neurons. Deletions or point mutations of a gene located at Xp22.3 (KAL1) are responsible for the disease. This gene encodes for a secreted heparin-binding protein (KAL or anosmin-1) which exhibits similarities with cell-adhesion molecules. In the present study, we show for the first time a direct action of anosmin-1 on the migratory activity of GnRH neurons. Specifically, we exposed immortalized migrating GnRH neurons (GN11 cells) to conditioned media (CM) of COS or CHO cells transiently transfected with human KAL1 gene in microchemotaxis and collagen gel assays. We found that anosmin-1-enriched media produced a cell-specific chemotactic response of GN11 cells. None of the CM enriched on three forms of anosmin-1 carrying different missense mutations (N267K, E514K and F517L) found in patients affected by X-linked KS affected the chemomigration of GN11 cells. Anosmin binds to the GN11 cell surface by interacting with the heparan sulphate proteoglycans, and the chemotactic effect of anosmin-1-enriched CM can be specifically blocked by heparin or by heparitinase pretreatment. These results strongly suggest an involvement of anosmin-1 in the control of the migratory behaviour of GnRH neurons and provide novel information on the pathogenesis of KS.


Assuntos
Proteínas da Matriz Extracelular/genética , Hormônio Liberador de Gonadotropina/metabolismo , Síndrome de Kallmann/genética , Proteínas do Tecido Nervoso/genética , Neurônios/fisiologia , Animais , Linhagem Celular , Quimiotaxia , Chlorocebus aethiops , Cromossomos Humanos X , Cricetinae , Cricetulus , Proteínas da Matriz Extracelular/metabolismo , Humanos , Camundongos , Mutação , Mutação de Sentido Incorreto , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Mutação Puntual
9.
Eur J Neurosci ; 18(6): 1410-8, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14511321

RESUMO

In this report we studied and compared the biochemical and the electrophysiological characteristics of two cell lines (GT1-7 and GN11) of immortalized mouse LHRH-expressing neurons and the correlation with their maturational stage and migratory activity. In fact, previous results indicated that GN11, but not GT1-7, cells exhibit an elevated motility in vitro. The results show that the two cell lines differ in terms of immunoreactivity for tyrosine hydroxylase and nestin as well as of production and release of 3,4-dihydroxyphenylalanine (DOPA) and of intracellular distribution and release of the LHRH. Patch-clamp recordings in GN11 cells, reveal the presence of a single inward rectifier K+ current indicative of an immature neuronal phenotype (neither firing nor electrical activity). In contrast, as known from previous studies, GT1-7 cells show the characteristics of mature LHRH neurons with a high electrical activity characterized by spontaneous firing and excitatory postsynaptic potentials. K+-induced depolarization induces in GT1-7 cells, but not in GN11 cells, a strong increase in the release of LHRH in the culture medium. However, depolarization of GN11 cells significantly decreases their chemomigratory response. In conclusion, these results indicate that GT1-7 and GN11 cells show different biochemical and electrophysiological characteristics and are representative of mature and immature LHRH neurons, respectively. The early stage of maturation of GN11 cells, as well as the low electrical activity detected in these cells, appears to correlate with their migratory activity in vitro.


Assuntos
Diferenciação Celular/fisiologia , Movimento Celular/fisiologia , Hormônio Liberador de Gonadotropina/metabolismo , Proteínas do Tecido Nervoso , Neurônios/fisiologia , Anestésicos Locais/farmacologia , Animais , Monoaminas Biogênicas/análise , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Bloqueadores dos Canais de Cálcio/farmacologia , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Césio/farmacologia , Quimiotaxia/efeitos dos fármacos , Cloretos/farmacologia , Di-Hidroxifenilalanina/metabolismo , Relação Dose-Resposta a Droga , Imuno-Histoquímica , Proteínas de Filamentos Intermediários/metabolismo , Potenciais da Membrana/efeitos dos fármacos , Camundongos , Nestina , Condução Nervosa/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Nifedipino/farmacologia , Técnicas de Patch-Clamp/instrumentação , Técnicas de Patch-Clamp/métodos , Cloreto de Potássio/farmacologia , Tetrodotoxina/farmacologia , Fatores de Tempo , Células Tumorais Cultivadas , Tirosina 3-Mono-Oxigenase/metabolismo
10.
Arq. neuropsiquiatr ; 55(3A): 444-51, set. 1997. tab, graf
Artigo em Inglês | LILACS | ID: lil-209534

RESUMO

The studies on the factors that regulate the biology of the neuroblastoma cell lines may ofter important information on the development of tissues on organs that derive from the neural crest. In the present paper we study the action of epidermal growth factor (EGF) on two human neuroblastoma cell lines: SK-N-SH which is composed at least of two cellular phenotypes (neuroblastic and melanocytic/glial cells), and its pure neuroblastic subclone SH-SY5Y. The results show that EGF (10 ng/ml) significantly stimulates the incorporation of [3H]-thymidine in the SK-N-SH cells only in the presence of fetal bovine serum (FBS) (control = 58285 + 9327 cpm; EGF= 75523 + 4457; p<0.05). Such effect is not observed in the presence of a chemical defined medium, that is, in the absence of FBS (control = 100997 + 4375; EGF = 95268 + 4683; NS). In the SH-SY5Y cells the EGF does not modify the incorporation of [3H]thymidine either in the presence of 10 percent of BFS (control = 113838 + 6978; EGF = 119434 + 9411; NS) or in its absence (control = 46197 + 3335; EGF = 44472 + 3493; NS). The results here reported suggest that: a) EGF may effect the proliferation of cells derived from a primary human neuroblastoma; b) this is evident by the EGF-induced increase of [3H]-thymidine incorporation in SK-N-SH cells; c) it is required the presence of other growth factors, present in the FBS, for the mitogenic action to be accomphished; d) since the pure neuroblastic SH-SY5Y cell line are refractory to the EGF, the effects observed in SK-N-SH cells probably occur on the melanocytic/glial cell subpopulation.


Assuntos
Humanos , Fator de Crescimento Epidérmico/farmacologia , Técnicas In Vitro , Neuroblastoma , Timidina/fisiologia , Células Tumorais Cultivadas/efeitos dos fármacos
11.
RBM rev. bras. med ; 43(8): 215-8, ago. 1986. ilus
Artigo em Português | LILACS | ID: lil-35600

RESUMO

Os estudos desenvolvidos nos últimos anos, levaram a um rápido avanço nos conhecimentos do papel fisiológico e fisiopatológico dos Peptídeos Opióides Endógenos. Sabemos que estes peptídeos derivam de três precursores, nominalmente proopiomelanocortina, proencefalinas A e B, originando três grupos de substâncias, que têm em comum atividade semelhante aos derivados do ópio. Agem através de seis receptores de membrana denominados pelas letras gregas: mi, delta, capa, sigma, lambda e épsilo. Têm açöes no sistema endócrino, exercendo um controle inibitório sobre a secreçäo de TSH, e do LH, e estimulatório sobre a secreçäo de ADH, da oxitocina, do ACTH, da prolactina e do hormônio de crescimento. Participam também do metabolismo dos carbo-hidratos e na regulaçäo do apetite


Assuntos
Endorfinas/farmacologia , Endorfinas/biossíntese
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