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1.
J Affect Disord ; 227: 713-720, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29179141

RESUMO

BACKGROUND: Findings from efficacy trials of group psychoeducation (PE) for bipolar disorders (BD) led to its inclusion in evidence-based guidelines as a first-line mandatory treatment. However, pragmatic trials and observational studies are needed to determine its real-world effectiveness, impact on outcomes deemed important to patients and to clarify potential mediators of any benefits. METHODS: Individuals with BD were offered the opportunity to participate in 20h of PE and asked to complete pre- and post-intervention ratings of symptoms, knowledge about BD, medication adherence, and illness perception. A priori, two key patient outcomes were identified (social functioning and self-esteem); sample attrition due to dropout or relapse was recorded. RESULTS: Of 156 individuals who completed the pre-PE assessments, 103 completed the program and post-PE assessments. Only 4 of 53 dropouts were associated with BD relapse. Post-intervention, the PE completers demonstrated a statistically significant improvement in social functioning (p = 0.003, Effect Size (ES) = 0.26) and a trend towards improved self-esteem (ES = 0.14). Whilst there were significant changes in medication adherence (p = 0.002, ES = 0.28), knowledge of BD (p < 0.001, ES = 1.20), and illness perception (p < 0.001, ES = -0.37), mediational analysis demonstrated that only change in illness perception was associated to change in functioning (p=0.03) with no contribution from changes in knowledge of BD or medication adherence. CONCLUSIONS: In real-world settings, over 60% individuals completed 10-session course of PE. After controlling for demography and baseline clinical state, change in illness perception, rather than change in knowledge or medication adherence, emerged as a potential mediator of some benefits of PE.


Assuntos
Terapia Cognitivo-Comportamental/métodos , Adesão à Medicação/psicologia , Cooperação do Paciente/psicologia , Educação de Pacientes como Assunto/métodos , Adulto , Transtorno Bipolar/psicologia , Transtorno Bipolar/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Prevenção Secundária , Resultado do Tratamento
2.
Epidemiol Infect ; 144(14): 3068-3079, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27435434

RESUMO

The objectives of this work were (i) geographical analysis of the 2012-2014 outbreak of rabies in Greece using GIS and (ii) comparative analysis of animal cases with data of potential human exposure to rabies together with environmental data, in order to provide information for risk assessment, effective monitoring and control. Most animal cases (40/48) involved red foxes, while domestic animals were also diagnosed with rabies. Overall, 80% of the cases were diagnosed in central northern Greece; 75% of the cases were diagnosed in low altitudes (<343·5 m), within a distance of 1 km from human settlements. Median distance from livestock farms was 201·25 m. Most people potentially exposed to rabies (889/1060) presented with dog bite injuries. Maximum entropy analysis revealed that distance from farms contributed the highest percentage in defining environmental niche profiles for rabid foxes. Oral vaccination programmes were implemented in 24 administrative units of the country during 2013 and 2014, covering a total surface area of ~60 000 km2. Rabies re-occurrence in Greece emphasizes the need for ongoing surveillance in cross-border areas and in areas with intense human activity.


Assuntos
Doenças do Gato/epidemiologia , Doenças dos Bovinos/epidemiologia , Surtos de Doenças , Doenças do Cão/epidemiologia , Raposas , Raiva/veterinária , Animais , Doenças do Gato/virologia , Gatos , Bovinos , Doenças dos Bovinos/virologia , Doenças do Cão/virologia , Cães , Sistemas de Informação Geográfica , Grécia/epidemiologia , Humanos , Raiva/epidemiologia , Vacina Antirrábica/administração & dosagem , Medição de Risco , Vacinação/veterinária
3.
Crit Rev Anal Chem ; 46(6): 521-37, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26980177

RESUMO

The quest to improve the detection of biomolecules and cells in health and life sciences has led to the discovery and characterization of various affinity bioprobes. Libraries of synthetic oligonucleotides (ssDNA/ssRNA) with randomized sequences are employed during Systematic Evolution of Ligands by Exponential Enrichment (SELEX) to select highly specific affinity probes called aptamers. With much focus on the generation of aptamers for a variety of target molecules, conventional SELEX protocols have been modified to develop new and improved SELEX protocols yielding highly specific and stable aptamers. Various techniques have been used to analyze the binding interactions between aptamers and their cognate molecules with associated merits and limitations. This article comprehensively reviews research advancements in the generation of aptamers, analyses physicochemical conditions affecting their binding characteristics to cellular and biomolecular targets, and discusses various field applications of aptameric binding. Biophysical techniques employed in the characterization of the molecular and binding features of aptamers to their cognate targets are also discussed.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnica de Seleção de Aptâmeros/métodos , Sítios de Ligação , Ligantes
4.
Epidemiol Infect ; 143(10): 2137-60, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25266682

RESUMO

The bacterium Francisella tularensis causes the vector-borne zoonotic disease tularemia, and may infect a wide range of hosts including invertebrates, mammals and birds. Transmission to humans occurs through contact with infected animals or contaminated environments, or through arthropod vectors. Tularemia has a broad geographical distribution, and there is evidence which suggests local emergence or re-emergence of this disease in Europe. This review was developed to provide an update on the geographical distribution of F. tularensis in humans, wildlife, domestic animals and vector species, to identify potential public health hazards, and to characterize the epidemiology of tularemia in Europe. Information was collated on cases in humans, domestic animals and wildlife, and on reports of detection of the bacterium in arthropod vectors, from 38 European countries for the period 1992-2012. Multiple international databases on human and animal health were consulted, as well as published reports in the literature. Tularemia is a disease of complex epidemiology that is challenging to understand and therefore to control. Many aspects of this disease remain poorly understood. Better understanding is needed of the epidemiological role of animal hosts, potential vectors, mechanisms of maintenance in the different ecosystems, and routes of transmission of the disease.


Assuntos
Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/veterinária , Francisella tularensis/isolamento & purificação , Tularemia/epidemiologia , Tularemia/veterinária , Zoonoses/epidemiologia , Zoonoses/microbiologia , Animais , Aves , Doenças Transmissíveis Emergentes/microbiologia , Europa (Continente)/epidemiologia , Humanos , Invertebrados , Mamíferos , Topografia Médica , Tularemia/microbiologia
6.
Cancer Lett ; 352(2): 236-44, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25016061

RESUMO

Pheochromocytomas and paragangliomas are rare neuroendocrine tumors which develop from chromaffin cells of the adrenal medulla and extra-adrenal sites, leading to excess catecholamine release and hypertension. Many of the tumors are characterized by a high vascularity, suggesting the possible implementation of anti-angiogenic therapies for patients. Here, the efficacy of the tyrosine kinase inhibitors sunitinib and sorafenib was investigated in vivo and in vitro. Oral treatment with either sunitinib or sorafenib (40mg/kg/day) for 14days induced a marked reduction in the volume and weight of PC12 pheochromocytoma cell tumor xenografts in mice. Assessment of tumoral neo-angiogenesis, assessed by morphometric analysis of the vascular network after CD31 immunolabeling, showed that both sunitinib and sorafenib reduced the microvessel area (-85% and -80%, respectively) and length (-80% and -78%, respectively) in treated compared to control tumors. In addition, the number of vessel nodes was significantly lower in treated tumors (-95% and -84%, respectively). Furthermore, cleaved caspase 3 immunolabeling revealed a marked increase in the number of apoptotic cells in tumors from treated animals. Sunitinib and sorafenib could exert a direct effect on PC12 cell viability in vitro. While sunitinib induced a rapid (4h) and pronounced (5-fold) increase in caspase-3/7-dependent apoptosis, sorafenib seems to exert its cytotoxic activity through a different mechanism. Altogether, our data demonstrate that sunitinib and sorafenib have the ability to impair pheochromocytoma development by inhibiting angiogenesis and reducing tumor cell viability. These results strongly suggest that both sunitinib and sorafenib could represent valuable therapeutic tools for pheochromocytoma.


Assuntos
Neoplasias das Glândulas Suprarrenais/tratamento farmacológico , Inibidores da Angiogênese/farmacologia , Indóis/farmacologia , Niacinamida/análogos & derivados , Compostos de Fenilureia/farmacologia , Feocromocitoma/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Pirróis/farmacologia , Administração Oral , Neoplasias das Glândulas Suprarrenais/irrigação sanguínea , Neoplasias das Glândulas Suprarrenais/enzimologia , Neoplasias das Glândulas Suprarrenais/patologia , Inibidores da Angiogênese/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Xenoenxertos , Indóis/administração & dosagem , Masculino , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neovascularização Patológica , Niacinamida/administração & dosagem , Niacinamida/farmacologia , Células PC12 , Compostos de Fenilureia/administração & dosagem , Feocromocitoma/irrigação sanguínea , Feocromocitoma/enzimologia , Feocromocitoma/patologia , Inibidores de Proteínas Quinases/administração & dosagem , Pirróis/administração & dosagem , Ratos , Sorafenibe , Sunitinibe , Fatores de Tempo , Carga Tumoral/efeitos dos fármacos
7.
Epidemiol Infect ; 142(6): 1205-13, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24001524

RESUMO

SUMMARY: The occurrence of Anaplasma phagocytophilum was investigated in spleen and serum samples from Swedish moose (Alces alces) in southern Sweden (island and mainland). Samples were analysed for presence of A. phagocytophilum DNA by real-time PCR (n = 263), and for Anaplasma antibodies with ELISA serology (n = 234). All serum samples had antibodies against A. phagocytophilum. The mean DNA-based prevalence was 26·3%, and significant (P < 0·01) temporal, and spatial variation was found. Island moose had significantly (P < 0·001) higher prevalence of A. phagocytophilum DNA than moose from the mainland areas. Two samples were sequenced to determine genetic variation in the 16S rRNA and groESL genes. Genetic sequence similarity with the human granulocytic anaplasmosis agent, equine granulocytic ehrlichiosis agent, and different wildlife-associated A. phagocytophilum variants were observed in the 16S rRNA and groESL genes. Our study shows that moose are exposed to A. phagocytophilum in Sweden, and represent a potential wildlife reservoir of the pathogen.


Assuntos
Anaplasma phagocytophilum/isolamento & purificação , Cervos , Ehrlichiose/veterinária , Anaplasma phagocytophilum/genética , Animais , Anticorpos Antibacterianos/sangue , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Chaperoninas/genética , Chaperoninas/metabolismo , DNA Bacteriano/genética , Reservatórios de Doenças , Ehrlichiose/epidemiologia , Ehrlichiose/microbiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Regulação Bacteriana da Expressão Gênica , Variação Genética , Masculino , RNA Bacteriano/genética , RNA Bacteriano/isolamento & purificação , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Suécia/epidemiologia , Fatores de Tempo
8.
Encephale ; 38(3): 266-73, 2012 Jun.
Artigo em Francês | MEDLINE | ID: mdl-22726415

RESUMO

An accurate treatment of first episodes in schizophrenia and bipolar disorders has a significant impact on compliance and prognosis. However, existing therapeutic guidelines may be poorly respected and may concern only typical clinical situations. Medical attitudes in clinical practice have been collected and structured on the basis of small interactive meetings (Focus Group [FG]), and a synthesis of practical attitudes has been compared with updated guidelines. The FG method applied to treatment initiation in schizophrenia and bipolar disorder is seen as complementary to evidence-based guidelines. It reveals that, in a reflexive manner, clinical attitudes are often more diverse and frequently consider first treatments after global evaluation, taking more into account external factors such as clinicians' experience, patient's history and willingness, clinical setting, and environment. A symptomatic approach is sometimes preferred, and a better alliance is always considered as a main objective. The FG method could be a supplementary support to continuous medical education.


Assuntos
Antimaníacos/administração & dosagem , Antipsicóticos/administração & dosagem , Transtorno Bipolar/tratamento farmacológico , Grupos Focais , Transtornos Psicóticos/tratamento farmacológico , Esquizofrenia/tratamento farmacológico , Psicologia do Esquizofrênico , Adulto , Sistemas de Notificação de Reações Adversas a Medicamentos , Idoso , Antimaníacos/efeitos adversos , Antipsicóticos/efeitos adversos , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/psicologia , Esquema de Medicação , Interações Medicamentosas , Quimioterapia Combinada , Medicina Baseada em Evidências , Feminino , Humanos , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/psicologia , Esquizofrenia/diagnóstico
9.
J Mol Endocrinol ; 48(2): 115-27, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22217803

RESUMO

We have previously demonstrated that measurement of tissue concentrations of the secretogranin II (SgII or SCG2 as listed in the HUGO database)-derived peptide EM66 may help to discriminate between benign and malignant pheochromocytomas and that EM66 represents a sensitive plasma marker of pheochromocytomas. Here, we investigated the gene expression and protein production of SgII in 13 normal adrenal glands, and 35 benign and 16 malignant pheochromocytomas with the goal to examine the molecular mechanisms leading to the marked variations in the expression of EM66 in tumoral chromaffin tissue. EM66 peptide levels were 16-fold higher in benign than in malignant pheochromocytomas and had an area under the receiver-operating characteristic curve of 0.95 for the distinction of benign and malignant tumors. Q-PCR experiments indicated that the SgII gene was significantly underexpressed in malignant tumors compared with benign tumors. Western blot analysis using antisera directed against SgII and SgII-derived fragments revealed lower SgII protein and SgII-processing products in malignant tumors. Western blot also showed that low p-cAMP-responsive element-binding (CREB) concentrations seemed to be associated with the malignant status. In addition, the prohormone convertase PC1 and PC2 genes and proteins were overexpressed in benign pheochromocytomas compared with malignant pheochromocytomas. Low concentrations of EM66 found in malignant tumors are associated with reduced expression and production of SgII and SgII-derived peptides that could be ascribed to a decrease in SgII gene transcription, probably linked to p-CREB down-regulation, and to lower PC levels. These findings highlight the mechanisms leading to lower concentrations of EM66 in malignant pheochromocytoma and strengthen the notion that this peptide is a suitable marker of this neuroendocrine tumor.


Assuntos
Neoplasias das Glândulas Suprarrenais/metabolismo , Biomarcadores Tumorais/metabolismo , Fragmentos de Peptídeos/metabolismo , Feocromocitoma/metabolismo , Secretogranina II/metabolismo , Adolescente , Neoplasias das Glândulas Suprarrenais/genética , Neoplasias das Glândulas Suprarrenais/patologia , Glândulas Suprarrenais/patologia , Glândulas Suprarrenais/fisiologia , Adulto , Idoso , Biomarcadores Tumorais/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/genética , Feocromocitoma/genética , Feocromocitoma/patologia , Pró-Proteína Convertase 1/genética , Pró-Proteína Convertase 1/metabolismo , Pró-Proteína Convertase 2/genética , Pró-Proteína Convertase 2/metabolismo , Secretogranina II/genética , Adulto Jovem
10.
Eur Psychiatry ; 27(8): 570-6, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21978427

RESUMO

BACKGROUND: The clinical and dimensional features associated with suicidal behaviour in bipolar patients during euthymic states are not well characterised. METHODS: In a sample of 652 euthymic bipolar patients, we assessed clinical features with the Diagnostic Interview for Genetics Studies (DIGS) and dimensional characteristics with questionnaires measuring impulsivity/hostility and affective lability/intensity. Bipolar patients with and without suicidal behaviour were compared for these clinical and dimensional variables. RESULTS: Of the 652 subjects, 42.9% had experienced at least one suicide attempt. Lifetime history of suicidal behaviour was associated with being a woman, a history of head injury, tobacco misuse and indicators of severity of bipolar disorder including early age at onset, high number of depressive episodes, positive history of rapid cycling, alcohol misuse and social phobia. Indirect hostility and irritability were dimensional characteristics associated with suicidal behaviour in bipolar patients, whereas impulsivity and affective lability/intensity were not associated with suicidal behaviour. LIMITATIONS: This study had a retrospective design with no replication sample. CONCLUSIONS: Bipolar patients with earlier onset, mood instability (large number of depressive episodes, rapid cycling) and/or particular addictive and anxiety comorbid disorders might be at high risk of suicidal behaviour. In addition, hostility dimensions (indirect hostility and irritability), may be trait components associated with suicidal behaviour in euthymic bipolar patients.


Assuntos
Transtorno Ciclotímico/fisiopatologia , Tentativa de Suicídio/psicologia , Adulto , Transtorno Ciclotímico/epidemiologia , Transtorno Ciclotímico/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais
11.
Arch Pediatr ; 16(11): 1491-8, 2009 Nov.
Artigo em Francês | MEDLINE | ID: mdl-19800205

RESUMO

There are no official guidelines for the treatment of anorexia nervosa in young patients. Some recommendations have been proposed by a group of British experts (N.I.C.E., 2004), based on results from controlled studies. Our inpatient care unit takes into account the different dimensions of anorexia nervosa in this subgroup of young patients and proposes an integrated approach including medical care, nutritional care, and psychological care, as suggested by the N.I.C.E. recommendations. We attempt to take into account variables that are unique to these young patients. More specifically, we insist on weight restoration that will permit adequate growth and we do not systematically separate the patient from his or her family. In addition, family therapy or counseling is systematically provided. The aim of this approach is to support parents, to provide psychoeducational guidance, and to help the family acquire new behaviors and new ways of understanding the eating disorder. Most patients are treated on an outpatient basis, but inpatient care is offered when the patient displays severe medical conditions or a severe comorbid psychiatric illness. Anorexia nervosa is a protracted disorder that requires multidisciplinary outpatient medical follow-up, including the intervention of a general practitioner and a psychiatric team.


Assuntos
Anorexia Nervosa/terapia , Hospitalização , Equipe de Assistência ao Paciente , Unidade Hospitalar de Psiquiatria , Psicoterapia/métodos , Adolescente , Assistência Ambulatorial , Criança , Terapia Combinada , Comportamento Cooperativo , Medicina Baseada em Evidências , Medicina de Família e Comunidade , Terapia Familiar , Humanos , Comunicação Interdisciplinar , Avaliação Nutricional , Apoio Nutricional , Guias de Prática Clínica como Assunto , Terapia Psicanalítica , Psicoterapia de Grupo/métodos , Aumento de Peso
12.
J Neuroendocrinol ; 17(6): 372-8, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15929742

RESUMO

The neuroendocrine protein secretogranin II is the precursor of several neuropeptides, including secretoneurin and a novel 66-amino acid peptide, EM66, the sequence of which has been highly conserved across the vertebrae phylum. The presence of EM66 has been detected in the adult and fetal human adrenal gland, as well as the rat pituitary and adrenal glands. The present study aimed to explore a possible neuroendocrine role of EM66 by analysing its occurrence and distribution within the jerboa hypothalamus, and its potential implication in the control of feeding behaviour. High-performance liquid chromatography analysis of jerboa hypothalamic extracts combined with a radioimmunoassay of EM66 revealed a single peak of immunoreactive material exhibiting the same retention time as recombinant EM66. Immunocytochemical labelling showed that EM66-producing neurones are widely distributed in several hypothalamic regions, including the preoptic area, the suprachiasmatic, supraoptic, parvocellular paraventricular and arcuate nuclei, and the lateral hypothalamus. Food deprivation for 5 days induced a significant increase in the number of EM66-containing neurones within the arcuate nucleus (105% increase) and the parvocellular aspect of the paraventricular nucleus (115% increase), suggesting that EM66 could be involved in the control of feeding behaviour and/or the response to stress associated with fasting. Altogether, these data reveal the physiological plasticity of the EM66 system in the hypothalamus and implicate this novel peptide in the regulation of neuroendocrine functions.


Assuntos
Núcleo Arqueado do Hipotálamo/metabolismo , Cromograninas/metabolismo , Privação de Alimentos/fisiologia , Núcleo Hipotalâmico Paraventricular/metabolismo , Fragmentos de Peptídeos/metabolismo , Secretogranina II/metabolismo , Sequência de Aminoácidos , Animais , Cromograninas/química , Comportamento Alimentar/fisiologia , Feminino , Imuno-Histoquímica , Masculino , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Roedores , Secretogranina II/química
16.
Microsc Res Tech ; 54(3): 137-57, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11458398

RESUMO

Pituitary adenylate cyclase-activating polypeptide (PACAP), a novel peptide of the secretin/glucagon/vasoactive intestinal polypeptide superfamily, has been initially characterized in mammals in 1989 and, only 2 years later, its counterpart has been isolated in amphibians. A number of studies conducted in the frog Rana ridibunda have demonstrated that PACAP is widely distributed in the central nervous system (particularly in the hypothalamus and the median eminence) and in peripheral organs including the adrenal gland. The cDNAs encoding the PACAP precursor and 3 types of PACAP receptors have been cloned in amphibians and their distribution has been determined by in situ hybridization histochemistry. Ontogenetic studies have revealed that PACAP is expressed early in the brain of tadpoles, soon after hatching. In the frog Rana ridibunda, PACAP exerts a large array of biological effects in the brain, pituitary, adrenal gland, and ovary, suggesting that, in amphibians as in mammals, PACAP may act as neurotrophic factor, a neurotransmitter and a neurohormone.


Assuntos
Glândulas Suprarrenais/metabolismo , Encéfalo/metabolismo , Neuropeptídeos/metabolismo , Rana ridibunda/metabolismo , Receptores do Hormônio Hipofisário/metabolismo , Sequência de Aminoácidos , Animais , Humanos , Dados de Sequência Molecular , Neuropeptídeos/química , Neuropeptídeos/genética , Neuropeptídeos/isolamento & purificação , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase
17.
Mol Pharmacol ; 60(1): 42-52, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11408599

RESUMO

Secretoneurin (SN) is a novel bioactive peptide that derives from the neuroendocrine protein secretogranin II (SgII) by proteolytic processing and participates in neuro-immune communication. The neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP-38) dose-dependently stimulates (EC(50) approximately 3 nM) SN release (up to 4-fold) and SgII gene expression (up to 60-fold) in cultured bovine adrenochromaffin cells. The effect of PACAP on both SN secretion and SgII mRNA levels is rapid and long lasting. We analyzed in this neuroendocrine cell model the transduction pathways involved in both SN secretion and SgII gene transcription in response to PACAP. The cytosolic calcium chelator BAPTA-AM and the nonselective calcium channel antagonist NiCl(2) equally inhibited both secretion of the peptide and transcription of the SgII gene, indicating a major contribution of calcium influx in PACAP-induced SN biosynthesis and release in chromaffin cells. Inhibition of protein kinase A (PKA) or C (PKC) also reduced PACAP-evoked SN release but did not alter the stimulatory effect of PACAP on SgII mRNA levels. Conversely, application of mitogen-activated protein kinase inhibitors suppressed PACAP-induced SgII gene expression. The effect of PACAP on SgII mRNA levels, like the effect of the PKC stimulator 12-O-tetradecanoylphorbol-13-acetate (TPA), was not affected by cycloheximide, whereas the effects of the PKA stimulator forskolin or cell-depolarization by high K(+) were significantly reduced by the protein synthesis inhibitor. PACAP and TPA both increased the binding activity of the SgII cAMP response element to trans-acting factors present in chromaffin cell nuclear extracts, which are recognized by antibodies to activator protein-1-related proteins. These data indicate that SN biosynthesis is regulated by PACAP in chromaffin cells through complex signaling cascades, suggesting that SN may play a function during trans-synaptic stimulation of the adrenal medulla.


Assuntos
Células Cromafins/efeitos dos fármacos , Neuropeptídeos/metabolismo , Neuropeptídeos/farmacologia , Proteínas/genética , Fator de Transcrição AP-1/metabolismo , Transcrição Gênica/efeitos dos fármacos , Animais , Sítios de Ligação , Transporte Biológico/efeitos dos fármacos , Cálcio/metabolismo , Carcinógenos/farmacologia , Bovinos , Células Cultivadas , Células Cromafins/metabolismo , Células Cromafins/fisiologia , Cromogranina A , Cromograninas/metabolismo , Colforsina/farmacologia , Cicloeximida/farmacologia , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Neuropeptídeos/efeitos dos fármacos , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Potássio/farmacologia , Proteínas Quinases/metabolismo , Inibidores da Síntese de Proteínas/farmacologia , Proteínas/efeitos dos fármacos , Secretogranina II , Acetato de Tetradecanoilforbol/farmacologia , Fatores de Tempo , Fator de Transcrição AP-1/efeitos dos fármacos
18.
J Comp Neurol ; 431(1): 11-27, 2001 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-11169987

RESUMO

The anatomic distribution and biochemical characteristics of the neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) were investigated in the central nervous system of the frog, Rana ridibunda, during development. Three to four days after hatching, at stages IV-VII, PACAP-immunoreactive perikarya were detected in the dorsal thalamus within the anterior ventral area, and a few fibers were found in the medial pallium. Positive cell bodies were first observed in the hypothalamus at stages VIII-IX, at the level of the dorsal and ventral infundibular nuclei. In these regions, the number of positive perikarya increased during ontogeny. In tadpoles, during the mid- and late premetamorphosis, a more complex organization of the PACAP-immunoreactive system was found in the thalamus with the appearance, at stages IX-XII, of two additional groups of positive neurons in the ventrolateral area and posterocentral nucleus. At stages XIII-XVIII of larval development and subsequent larval stages, PACAP-immunoreactive fibers were found in the median eminence. In newly metamorphosed animals, several additional groups of positive perikarya appeared in the medial pallium, the preoptic nucleus, the torus semicircularis, the tegmentum of the mesencephalon, and the cerebellum. The immunoreactive peptide contained in the tadpole brain was characterized by high performance liquid chromatography analysis combined with radioimmunoassay quantification. At all stages investigated, the predominant form of PACAP-immunoreactive material coeluted with synthetic frog PACAP38. The occurrence of PACAP soon after hatching indicates that the peptide may exert neurotrophic activities. The existence of immunoreactive elements in several thalamic regions at mid- and late premetamorphic stages suggests that PACAP may act as a neurotransmitter, neuromodulator, or both, during ontogenesis. Finally, the presence of PACAP-immunoreactive perikarya in hypothalamic nuclei and nerve fibers in the median eminence supports the view that PACAP may play a role in the control of pituitary hormone secretion during larval development.


Assuntos
Encéfalo/enzimologia , Larva/crescimento & desenvolvimento , Neuropeptídeos/metabolismo , Rana ridibunda/crescimento & desenvolvimento , Fatores Etários , Animais , Encéfalo/citologia , Imuno-Histoquímica , Larva/citologia , Larva/enzimologia , Metamorfose Biológica/fisiologia , Neurônios/citologia , Neurônios/enzimologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Hipófise/metabolismo , Rana ridibunda/anatomia & histologia , Rana ridibunda/metabolismo
19.
J Mol Endocrinol ; 25(2): 157-68, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11013344

RESUMO

Growth hormone-releasing hormone (GHRH) and pituitary adenylate cyclase-activating polypeptide (PACAP) belong to the same superfamily of regulatory neuropeptides and have both been characterized on the basis of their hypophysiotropic activities. This review describes the molecular evolution of the GHRH/PACAP gene family from urochordates to mammals and presents the hypothesis that the respective roles of GHRH and PACAP in the control of GH secretion are totally inverted in phylogenetically distant groups of vertebrates. In mammals, GHRH and PACAP originate from distinct precursors whereas, in all submammalian taxa investigated so far, including birds, amphibians and fish, a single precursor encompasses a GHRH-like peptide and PACAP. In mammals, GHRH-containing neurons are confined to the infundibular and dorsomedial nuclei of the hypothalamus while PACAP-producing neurons are widely distributed in hypothalamic and extrahypothalamic areas. In fish, both GHRH- and PACAP-immunoreactive neurons are restricted to the diencephalon and directly innervate the adenohypophysis. In mammals and birds, GHRH plays a predominant role in the control of GH secretion. In amphibians, both GHRH and PACAP are potent stimulators of GH release. In fish, PACAP strongly activates GH release whereas GHRH has little or no effect on GH secretion. The GHRH/PACAP family of peptides thus provides a unique model in which to investigate the structural and functional facets of evolution.


Assuntos
Hormônio Liberador de Hormônio do Crescimento/genética , Hormônio do Crescimento Humano/metabolismo , Neuropeptídeos/genética , Sequência de Aminoácidos , Animais , Encéfalo/anatomia & histologia , Encéfalo/metabolismo , Evolução Molecular , Variação Genética , Humanos , Dados de Sequência Molecular , Família Multigênica , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Homologia de Sequência de Aminoácidos
20.
Pharmacol Rev ; 52(2): 269-324, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10835102

RESUMO

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a 38-amino acid peptide that was first isolated from ovine hypothalamic extracts on the basis of its ability to stimulate cAMP formation in anterior pituitary cells. PACAP belongs to the vasoactive intestinal polypeptide (VIP)-glucagon-growth hormone releasing factor-secretin superfamily. The sequence of PACAP has been remarkably well conserved during the evolution from protochordate to mammals, suggesting that PACAP is involved in the regulation of important biological functions. PACAP is widely distributed in the brain and peripheral organs, notably in the endocrine pancreas, gonads, and respiratory and urogenital tracts. Characterization of the PACAP precursor has revealed the existence of a PACAP-related peptide whose activity remains unknown. Two types of PACAP binding sites have been characterized. Type I binding sites exhibit a high affinity for PACAP and a much lower affinity for VIP whereas type II binding sites have similar affinity for PACAP and VIP. Molecular cloning of PACAP receptors has shown the existence of three distinct receptor subtypes, the PACAP-specific PAC1 receptor, which is coupled to several transduction systems, and the two PACAP/VIP-indifferent VPAC1 and VPAC2 receptors, which are primarily coupled to adenylyl cyclase. PAC1 receptors are particularly abundant in the brain and pituitary and adrenal glands whereas VPAC receptors are expressed mainly in the lung, liver, and testis. The wide distribution of PACAP and PACAP receptors has led to an explosion of studies aimed at determining the pharmacological effects and biological functions of the peptide. This report reviews the current knowledge concerning the multiple actions of PACAP in the central nervous system and in various peripheral organs including the endocrine glands, the airways, and the cardiovascular and immune systems, as well as the different effects of PACAP on a number of tumor cell types.


Assuntos
Neuropeptídeos/farmacologia , Receptores do Hormônio Hipofisário/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Humanos , Dados de Sequência Molecular , Neuropeptídeos/química , Neuropeptídeos/genética , Neuropeptídeos/fisiologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Receptores do Hormônio Hipofisário/genética , Receptores Tipo II de Peptídeo Intestinal Vasoativo , Receptores Tipo I de Polipeptídeo Intestinal Vasoativo
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