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1.
Mol Biol Rep ; 47(6): 4345-4355, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32468255

RESUMO

Stearoyl-ACP desaturases (SADs) and fatty acid desaturases (FADs) play a critical role in plant lipid metabolism and also affect oil fatty acid composition introducing double bonds into the hydrocarbon chains to produce unsaturated fatty acids. In the present study, the genomic sequences of three SAD and three FAD candidate genes were characterized in olive and their expression was evaluated in different plant tissues. OeSAD genes corresponded to olive SAD1 and SAD2 and to a newly identified OeSAD4, sharing the conserved protein structure with other plant species. On the other hand, the full-length genomic sequences of two microsomal OeFAD genes (FAD2-1 and FAD2-2) and the plastidial FAD6, were released. When the level of expression was tested on different tissues of cv. Leccino, OeSAD1 and OeSAD2 were mainly expressed in the fruits, while OeFAD genes showed the lowest expression in this tissue. The mRNA profiling of all genes was directly studied in fruits of Leccino and Coratina cultivars during fruit development. In both genotypes, the expression level of OeSAD1 and OeSAD2 had the highest value during and after the pit-hardening period, when oil accumulation in fruit mesocarp is intensively increasing. Furthermore, the expression level of both OeFAD2 genes, which were the main candidates for oleic acid desaturation, were almost negligible during fruit ripening. These results have made possible to define candidate genes of the machinery regulation of fatty acid composition in olive oil, providing information on their sequence, gene structure and chromosomal location.


Assuntos
Ácidos Graxos Dessaturases/genética , Oxigenases de Função Mista/genética , Olea/genética , Ácidos Graxos/análise , Ácidos Graxos Insaturados , Frutas/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Olea/metabolismo , Ácido Oleico , Reguladores de Crescimento de Plantas/genética , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética
2.
Phys Med ; 119: 103300, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38325222

RESUMO

PURPOSE: The aim of the present study, conducted by a working group of the Italian Association of Medical Physics (AIFM), was to define typical z-resolution values for different digital breast tomosynthesis (DBT) models to be used as a reference for quality control (QC). Currently, there are no typical values published in internationally agreed QC protocols. METHODS: To characterize the z-resolution of the DBT models, the full width at half maximum (FWHM) of the artifact spread function (ASF), a technical parameter that quantifies the signal intensity of a detail along reconstructed planes, was analyzed. Five different commercial phantoms, CIRS Model 011, CIRS Model 015, Modular DBT phantom, Pixmam 3-D, and Tomophan, were evaluated on reconstructed DBT images and 82 DBT systems (6 vendors, 9 models) in use at 39 centers in Italy were involved. RESULTS: The ASF was found to be dependent on the detail size, the DBT angular acquisition range, the reconstruction algorithm and applied image processing. In particular, a progressively greater signal spread was observed as the detail size increased and the acquisition angle decreased. However, a clear correlation between signal spread and angular range width was not observed due to the different signal reconstruction and image processing strategies implemented in the algorithms developed by the vendors studied. CONCLUSIONS: The analysis led to the identification of typical z-resolution values for different DBT model-phantom configurations that could be used as a reference during a QC program.


Assuntos
Processamento de Imagem Assistida por Computador , Mamografia , Mamografia/métodos , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Artefatos , Algoritmos
3.
Br Poult Sci ; 54(3): 374-80, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23796119

RESUMO

1. This study was conducted to evaluate the influence of diet composition on egg number, physical and chemical characteristics of eggs and weight and survival of chicks throughout a breeding season in a captive-bred population of greater rheas (Rhea americana). 2. From August to December, individuals were offered two diets: processed feed for rheas and processed feed for chicken (which is the feed most commonly offered to farmed rheas in Argentina). Reproductive performance of 15 females was monitored and female body weight was recorded before egg-laying onset. Within each experimental group, the following variables were determined: egg morphometric variables and percentage of components, fatty acid composition, hatching success and initial weight of chicks and mortality during the first week of life. 3. Females that were fed on processed feed for rheas delayed onset of laying and reduced laying period and number of eggs produced. However, females of this group laid larger eggs, with higher percentages of yolk and yolk lipids, and exhibited higher hatching success and chick weight compared with those that received chicken diet. Survivorship of chicks in their first week of life was not affected by composition of the diet offered to parental female. 4. Some reproductive parameters of captive greater rhea females fed on processed feed for rheas were higher than those of individuals receiving processed feed for chicken.


Assuntos
Ração Animal/análise , Dieta/veterinária , Óvulo/fisiologia , Reiformes/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Animais Recém-Nascidos/fisiologia , Argentina , Peso Corporal , Cruzamento , Casca de Ovo , Clara de Ovo/química , Gema de Ovo/química , Feminino , Ovalbumina/análise , Oviposição/fisiologia , Óvulo/química , Estações do Ano
4.
Phys Med ; 96: 149-156, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35301162

RESUMO

The aim of this work was the investigation of the ion recombination and polarity factors (ksat ad kpol) for a PTW Advanced Markus ionization chamber exposed to proton and carbon ion beams at the Centro Nazionale di Adroterapia Oncologica. Measurements with protons were specifically dedicated for ocular treatments, in the low energy range and for small, collimated scanning fields. For both protons and carbon ions, several measurements were performed by delivering a 2D single energy layer of 3x3 cm2 and homogeneous, biologically-optimized SOBPs. Data were collected at different depths in water, by varying the voltage values of the ionization chamber and for two different dose rates (the nominal one and one reduced to 20% of it). The ksat-values were determined from extrapolation of the saturation curves. Furthermore kpol-values were calculated using the recommendations from the International Atomic Energy Agency (IAEA) Technical Report Series (TRS)-398 Code of Practice. Results showed that the Advanced Markus performs optimally in this clinical scenario characterized by small treatment volumes and high dose gradients although for both particle types, but particularly for carbon ions, a charge multiplication effect up to 1.7% occurs at voltage higher than 150 V. For protons, both the ion recombination and polarity corrections were always smaller than 0.3%, for all the analysed cases and adopted dose rates, so not affecting the dosimetric measurements for clinical routine. For carbon ions the polarity effect can be neglected while ion recombination has to be carefully calculated and cannot be neglected since corrections even higher than 1% can be found, especially at high LET measuring points.


Assuntos
Terapia com Prótons , Prótons , Carbono , Íons , Radiometria/métodos , Síncrotrons
5.
Br Poult Sci ; 51(6): 838-46, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21161792

RESUMO

1. A study was conducted to evaluate how body weight and age of each female are related to the number and physical and chemical characteristics of the eggs produced throughout a breeding season in a captive-bred population of Greater Rheas (Rhea americana). 2. Reproductive performance of 15 females of three age classes (5 individuals per class) was monitored; female body weight was recorded before laying-onset. All the eggs laid were collected and identified, and different morphometric variables, percentage of components and fatty acid composition were determined. 3. The earlier the female started egg-laying, the longer the laying period and the greater the overall number of eggs produced. The onset of egg-laying in turn seemed to be related to the attainment of a high body weight. 4. Except for length, the values of the morphometric variables of the egg and unsaturated fatty acids (palmitoleic, oleic and linoleic) increased with female age. 5. High body weight was associated with low palmitic and palmitoleic fatty acids and high linoleic, linolenic and total unsaturated fatty acids. 6. Live weight and age of females can determine several physical and chemical characteristics of eggs.


Assuntos
Peso Corporal , Tamanho da Ninhada , Reiformes/fisiologia , Fatores Etários , Animais , Ácidos Graxos Monoinsaturados/metabolismo , Ácidos Graxos Insaturados/metabolismo , Feminino , Ácido Linoleico/metabolismo , Óvulo/citologia , Óvulo/metabolismo , Ácido Palmítico/metabolismo , Reprodução , Reiformes/anatomia & histologia , Fatores de Tempo
6.
Phys Med Biol ; 64(9): 095010, 2019 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-30844771

RESUMO

Within the dosimetric characterization of particle beams, laterally-integrated depth-dose-distributions (IDDs) are measured and provided to the treatment planning system (TPS) for beam modeling or used as a benchmark for Monte Carlo (MC) simulations. The purpose of this work is the evaluation, in terms of ion recombination and polarity effect, of the dosimetric correction to be applied to proton and carbon ion curves as a function of linear energy transfer (LET). LET was calculated with a MC code for selected IDDs. Several regions of Bragg peak (BP) curve were investigated. The charge was measured with the plane-parallel BP-ionization chamber mounted in the Peakfinder as a field detector, by delivering a fixed number of particles at the maximum flux. The dose rate dependence was evaluated for different flux levels. The chamber was connected to an electrometer and exposed to un-scanned pencil beams. For each measurement the chamber was supplied with {±400, +200, +100} V. Recombination and polarity correction factors were then calculated as a function of depth and LET in water. Three energies representative of the clinical range were investigated for both particle types. The corrected IDDs (IDD k s) were then compared against MC. Recombination correction factors were LET and energy dependent, ranging from 1.000 to 1.040 (±0.5%) for carbon ions, while nearly negligible for protons. Moreover, no corrections need to be applied due to polarity effect being <0.5% along the whole IDDs for both particle types. IDD k s showed a better agreement than uncorrected curves when compared to MC, with a reduction of the mean absolute variation from 1.2% to 0.9%. The aforementioned correction factors were estimated and applied along the IDDs, showing an improved agreement against MC. Results confirmed that corrections are not negligible for carbon ions, particularly around the BP region.


Assuntos
Radioterapia com Íons Pesados , Terapia com Prótons , Radiometria/instrumentação , Planejamento da Radioterapia Assistida por Computador/métodos , Algoritmos , Transferência Linear de Energia , Método de Monte Carlo , Água
7.
Ecancermedicalscience ; 10: 677, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27729942

RESUMO

PURPOSE: The aim of this retrospective study is to evaluate patient profile, feasibility, and acute toxicity of RadioTherapy (RT) delivered by VERO® in the first 20 months of clinical activity. METHODS: Inclusion criteria: 1) adult patients; 2) limited volume cancer (M0 or oligometastatic); 3) small extracranial lesions; 4) treatment between April 2012 and December 2013 and 5) written informed consent. Two techniques were employed: intensity modulated radiotherapy (IMRT) and stereotactic body radiotherapy (SBRT). Toxicity was evaluated using Radiation Therapy Oncology Group/European Organisation for Research and Treatment of Cancer (RTOG/EORTC) criteria. RESULTS: Between April 2012 and December 2013, 789 consecutive patients (957 lesions) were treated. In 84% of them one lesion was treated and in 16% more than one lesion were treated synchronously/metachronously; first radiotherapy course in 85%, re-irradiation in 13%, and boost in 2% of cases. The treated region included pelvis 46%, thorax 38%, upper abdomen 15%, and neck 1%. Radiotherapy schedules included <5 and >5 fractions in 75% and 25% respectively. All patients completed the planned treatment and an acceptable acute toxicity was observed. CONCLUSIONS: RT delivered by VERO® was administrated predominantly to thoracic and pelvic lesions (lung and urologic tumours) using hypofractionation. It is a feasible approach for limited burden cancer offering short and well accepted treatment with favourable acute toxicity profile. Further investigation including dose escalation and other available VERO® functionalities such as real-time dynamic tumour tracking is warranted in order to fully evaluate this innovative radiotherapy system.

8.
Metabolism ; 35(4): 337-42, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3515118

RESUMO

The effect of oral glucose and arginine infusion on plasma glucose, glucagon, serum insulin, and C-peptide concentrations was evaluated in 16 patients with hyperthyroid Graves' disease and in ten euthyroid age- and sex-matched normal subjects. Basal plasma glucose concentrations were significantly higher in the hyperthyroid patients, but the plasma glucose response following glucose and arginine administration was similar in the two groups. The insulin response was similar in the hyperthyroid and normal subjects after glucose administration and significantly lower during arginine infusion in the hyperthyroid patients. The serum C-peptide response to both glucose and arginine administration was markedly blunted in the hyperthyroid patients, and the plasma glucagon response to arginine infusion was decreased. These results suggest that pancreatic beta and alpha cell secretory function is impaired in hyperthyroidism as assessed by C-peptide and glucagon secretion following oral glucose administration and arginine infusion. The apparent discrepancy between C-peptide and insulin secretion in the hyperthyroid patients following glucose administration might be due to diminished hepatic extraction of insulin or enhanced metabolism of C-peptide.


Assuntos
Arginina/farmacologia , Peptídeo C/sangue , Glucagon/sangue , Glucose/farmacologia , Hipertireoidismo/sangue , Insulina/sangue , Adulto , Análise de Variância , Feminino , Teste de Tolerância a Glucose , Humanos , Ilhotas Pancreáticas/metabolismo , Masculino , Pessoa de Meia-Idade , Proinsulina/sangue
9.
Neuropeptides ; 15(3): 129-32, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2174517

RESUMO

The aim of this study was to evaluate beta-endorphin, ACTH, and cortisol plasma levels during metyrapone administration in man after chronic opioid receptor stimulation. Metyrapone (750 mg every 4 hr for 6 doses) was administered to ten male heroin addicts, who had been on a maintenance therapy with methadone for at least 6 months and to ten healthy sex- and age-matched volunteers. Before metyrapone administration the basal levels of cortisol and ACTH were significantly decreased in addicts as compared to normal controls, while plasma beta-endorphin was not different. The response of beta-endorphin and ACTH to metyrapone administration was significantly blunted in addicts (p less than 0.01). These results suggest that the chronic stimulation of opiate receptors can impair the function of the anterior pituitary gland.


Assuntos
Hormônio Adrenocorticotrópico/sangue , Dependência de Heroína/sangue , Hidrocortisona/sangue , Metirapona/farmacologia , beta-Endorfina/sangue , Adulto , Humanos , Masculino , Metadona , Receptores Opioides/fisiologia , Valores de Referência , Transtornos Relacionados ao Uso de Substâncias/sangue
10.
Behav Brain Res ; 81(1-2): 19-24, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8949997

RESUMO

Correlations between aggressiveness and its components and plasma concentrations of norepinephrine (NE), epinephrine (EPI), testosterone (T), cortisol (Cort) and prolactin (Prl) were studied in 158 physically and psychologically healthy male volunteers. Global aggressiveness, examined directly in the probands by the Buss-Durkee Hostility Inventory (BDHI), was not correlated with any of the biochemical parameters investigated, but reports by first-degree relatives and spouses showed positive correlations between global aggressiveness and NE and T levels. The BDHI scores for 'irritability' and 'resentment' were positively correlated with NE, T and Cort.


Assuntos
Agressão/fisiologia , Hormônios/fisiologia , Neurotransmissores/fisiologia , Adolescente , Adulto , Emoções/fisiologia , Epinefrina/sangue , Hormônios/sangue , Humanos , Hidrocortisona/sangue , Masculino , Pessoa de Meia-Idade , Neurotransmissores/sangue , Norepinefrina/sangue , Determinação da Personalidade , Prolactina/sangue , Valores de Referência , Testosterona/sangue
11.
Life Sci ; 51(4): 247-51, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1625515

RESUMO

In order to establish possible alterations in the gamma aminobutyric acid (GABA)ergic control of growth hormone (GH) secretion in heroin addicts, ten patients (age, 25.8 +/- 1.07 yr (mean +/- SE); duration of heroin addiction, range 3-8 yr; weight, 67.3 +/- 0.87 kg body weight), and ten age (29.1 +/- 0.84 yr)- and weight (69.7 +/- 0.87 kg)-matched normal controls were tested with the GABAergic B-receptor agonist baclofen (10 mg p.o. at 09.00 h) (experimental test) or a placebo (control test). Blood samples for GH assay were taken every 15 min for the next 150 min. Normal controls underwent one control and one experimental test. Heroin addicts were submitted to both baclofen and placebo test twice, once around the time of their admission to a recovery community for drug abusers, when they were still assuming heroin, and again after two months of permanence in the community. From the time of their admission to the community, the patients were forbidden to use heroin. For two weeks after admission they were treated with clonidine and acetylsalicilic acid to attenuate withdrawal symptoms. Thereafter, the patients underwent a period of wash-out of pharmacological treatments for at least 6 weeks before being retested. Basal GH levels were similar in normal controls and heroin addicts in all tests and remained unmodified during control tests in all subjects. The administration of baclofen increased four times the serum GH levels within 120 minutes in the normal controls, whereas it did not modify serum GH concentrations in heroin addicts either during the period of drug abuse or after two months of abstinence. These data show that the control of GH secretion mediated by GABAergic B-receptors is impaired in heroin addicts. It is hypothesized that this neuroendocrine alteration might represent a trait marker of heroin addiction, or more likely, that it was a consequence of a long addiction to heroin persisting after two months of abstinence.


Assuntos
Baclofeno/farmacologia , Hormônio do Crescimento/metabolismo , Dependência de Heroína/sangue , Adulto , Análise de Variância , Método Duplo-Cego , Hormônio do Crescimento/sangue , Hormônio do Crescimento/efeitos dos fármacos , Humanos , Masculino , Distribuição Aleatória
12.
Life Sci ; 62(7): 617-25, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9472721

RESUMO

The relationship between different degrees of normal aggressiveness (low, medium, high) and neurotransmitter-neuroendocrine responses to the administration of psychologically stressful tests (Mental Arithmetic, Stroop Color Word Interference task, Trial Social Stress test) was examined in thirty male peripubertal junior school adolescents. Plasma concentrations of norepinephrine (NE), epinephrine (EPI), ACTH, cortisol (CORT), growth hormone (GH), prolactin (PRL) and testosterone (T) were measured immediately before the beginning of the tests and at their end, 30 min later. High-normal aggressiveness have been found associated with significantly higher basal concentrations of NE, ACTH, PRL, and T and with a significant increase of GH responses to the stressful stimuli.


Assuntos
Comportamento do Adolescente/fisiologia , Agressão/fisiologia , Hormônios/fisiologia , Neurotransmissores/fisiologia , Estresse Psicológico/sangue , Estresse Psicológico/fisiopatologia , Adolescente , Hormônio Adrenocorticotrópico/sangue , Pressão Sanguínea/fisiologia , Criança , Epinefrina/sangue , Frequência Cardíaca/fisiologia , Hormônios/sangue , Hormônio do Crescimento Humano/sangue , Humanos , Hidrocortisona/sangue , Masculino , Neurotransmissores/sangue , Norepinefrina/sangue , Prolactina/sangue , Serotonina/sangue , Testosterona/sangue
13.
Int Clin Psychopharmacol ; 13(1): 1-9, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9988361

RESUMO

(+/-)3,4-Methylene-dioxymethamphetamine (MDMA, or 'Ecstasy') effects on serotonin system function and behaviour in humans are unclear. Fifteen MDMA users, who did not have other drug dependencies or alcohol abuse, and had not used other drugs for prolonged periods, and 15 control individuals were included in a study to assess the biological and psychological changes after chronic use of MDMA. Prolactin and cortisol responses to D-fenfluramine challenge, clinical psychobehavioural changes, personality characteristics, including mood, aggressiveness and temperamental aspects, were evaluated 3 weeks after MDMA discontinuation. MDMA users had significantly reduced prolactin and cortisol responses in comparison with control individuals (p < 0.001 and p < 0.005, respectively). Dysphoria and mood changes were exhibited in seven individuals, tiredness in five and sensation-seeking behaviour in twelve at the clinical evaluation. Significantly higher scores were found in MDMA individuals than in control individuals for Minnesota Multiphasic Personality Inventory subscale for Depression, for Buss Durkee Hostility Inventory direct and guilt subscales, for Hamilton Depression Rating Scale and for novelty-seeking Tridimensional Personality Questionnaire subscale. Prolactin responses to D-fenfluramine stimulation area under the curve among MDMA users were negatively correlated with direct aggressiveness scores for Buss Durkee Hostility Inventory; a negative correlation between prolactin responses and novelty-seeking scores was also evidenced among MDMA users. These data suggest an association between serotonin system impairment and MDMA use in humans; in interpretation of these results, the possibility that serotonin deficit in MDMA individuals was partially related to a premorbid condition, in relationship with novelty-seeking behaviour and mood disorders, can not be excluded.


Assuntos
Afeto/efeitos dos fármacos , Agressão/efeitos dos fármacos , Comportamento Exploratório/efeitos dos fármacos , Alucinógenos/farmacologia , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Serotonina/farmacologia , Adolescente , Adulto , Fenfluramina , Humanos , Hidrocortisona/análise , Masculino , Determinação da Personalidade , Serotoninérgicos
14.
Int Clin Psychopharmacol ; 9(3): 211-5, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7814832

RESUMO

Gamma-hydroxybutyric acid (GHBA) has been recently introduced for alcohol detoxication but few data are available concerning the central mechanism of action of this gamma-aminobutyric acid (GABA) catabolite. GHBA ability to stimulate growth hormone (GH) and prolactin (PRL) secretion has been reported: the involvement of GABA, dopamine or serotonin systems acting on pituitary hormones has been hypothesized. In the present study we investigated GH and PRL responses to GHBA with or without flumazenil (a benzodiazepine receptor antagonist) i.v. pretreatment. Our study included nine male healthy volunteers (aged 23.2 +/- 2.5 years) who were submitted to three tests in random order: (1) oral GHB administration; (2) oral GHBA and i.v. flumazenil administration; (3) oral placebo and i.v. saline administration. Blood samples for GH and PRL assays were collected during the three tests at -15, 0, 15, 30, 45, 60 and 90 min. GHBA induced a significant increase in GH plasma levels; flumazenil pretreatment antagonized GHBA action on GH secretion. No changes were obtained with placebo and saline administration. A subpopulation of GABA receptors or GHBA-specific receptors seems to be involved in GHBA action. The benzodiazepine receptor antagonist flumazenil was able to influence the sensitivity and the neuroendocrine consequences of GHBA binding site stimulation.


Assuntos
Flumazenil/farmacologia , Hormônio do Crescimento/sangue , Prolactina/sangue , Oxibato de Sódio/antagonistas & inibidores , Administração Oral , Adulto , Humanos , Injeções Intravenosas , Masculino , Pré-Medicação , Oxibato de Sódio/farmacologia
15.
Int Clin Psychopharmacol ; 10(4): 245-50, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8748046

RESUMO

Gamma-hydroxybutyric acid (GHB) has been recently used in alcohol detoxification, but conflicting data are available concerning the central mechanism of action of this GABA catabolite. GHB ability to stimulate growth hormone (GH) secretion has been reported. Our previous studies revealed the ability of flumazenil (a benzodiazepine antagonist) to counteract GHB effects on GH secretion. Other hypotheses, including an opioid or serotonergic role of GHB, have been considered. In the present study we investigated GH responses to GHB with or without naloxone (an opiate receptor antagonist) or metergoline (a serotonin receptor antagonist) pretreatment. This study included 10 male healthy volunteers (aged 24.3 +/- 2.9 years) who were submitted to four tests in random order: (A) oral GHB administration; (B) oral GHB and i.v. naloxone administration; (C) oral GHB and oral metergoline administration; and (D) oral placebo and i.v. saline administration. Blood samples for GH assay were collected during the three tests at -15, 0, 15, 30, 45, 60 and 90 min. GHB induced a significant increase in GH plasma levels; naloxone pretreatment did not antagonize GHB action on GH secretion; metergoline significantly decreased GH response to GHB (p < 0.05). No changes were obtained with placebo and saline administration. The opioid system does not seem to be involved in GHB effects on GH-secreting pituitary cells; GHB effects on the serotonergic system influencing GH secretion, on the other hand, cannot be excluded.


Assuntos
Hormônio do Crescimento/sangue , Metergolina/farmacologia , Naloxona/farmacologia , Oxibato de Sódio/farmacologia , Ácido gama-Aminobutírico/metabolismo , Adulto , Hormônio do Crescimento/efeitos dos fármacos , Humanos , Masculino
16.
Psychiatry Res ; 58(2): 153-60, 1995 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-8570767

RESUMO

The function of the central serotonergic system was examined indirectly through the measurement of prolactin (PRL) and cortisol responses to fenfluramine challenges in 27 heroin addicts 2 months after detoxification and in nine healthy volunteers. Heroin abusers included nine addicts with comorbid depressive disorders (Group A), nine with aggressive behavior and antisocial personality (Group B), and nine with heroin addiction uncomplicated by other Axis I and II psychiatric disorders (Group C). PRL and cortisol responses of patients in Group A were blunted, while those of patients in Groups B and C did not differ from those of the healthy volunteers. Cortisol responses in Group A differed significantly from those in the other patient groups and in the normal comparison group for AUC analyses, but the diagnosis x time interaction showed a significant difference only between Group A and the normal group. Our data suggest that the function of the serotonergic system is impaired in heroin addicts with comorbid depression but not in heroin addicts who are not clinically depressed. Thus, the serotonergic system does not appear to be impaired by prolonged opioid exposure, per se.


Assuntos
Fenfluramina , Dependência de Heroína/reabilitação , Hidrocortisona/sangue , Prolactina/sangue , Inibidores Seletivos de Recaptação de Serotonina , Serotonina/fisiologia , Adulto , Agressão/fisiologia , Transtorno da Personalidade Antissocial/fisiopatologia , Transtorno da Personalidade Antissocial/psicologia , Transtorno da Personalidade Antissocial/reabilitação , Transtorno Depressivo/fisiopatologia , Transtorno Depressivo/psicologia , Transtorno Depressivo/reabilitação , Dependência de Heroína/fisiopatologia , Dependência de Heroína/psicologia , Humanos , Masculino , Valores de Referência
17.
Psychiatry Res ; 77(2): 89-96, 1998 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-9541144

RESUMO

The function of the GABAergic system was examined in 20 subjects with heroin dependence and abuse, 2 months after detoxification, and in 10 healthy volunteers, by measuring the growth hormone (GH) response to a challenge with the GABA B receptor agonist baclofen. Ten heroin addicts had comorbid anxiety disorder (Group A), while the other ten had heroin addiction uncomplicated by Axis I and II psychopathologies (Group B). GH responses to baclofen stimulation of Group A patients were significantly blunted, while those of Group B subjects did not differ from responses of healthy volunteers. Our data show that the function of the GABAergic system is impaired only in heroin addicts with comorbid anxiety disorders (anxious cluster), suggesting that the GABA system is not persistently influenced by prolonged exposure to opioid receptor stimulation.


Assuntos
Transtornos de Ansiedade/psicologia , Dependência de Heroína/reabilitação , Heroína/farmacocinética , Receptores de GABA/metabolismo , Adulto , Análise de Variância , Transtornos de Ansiedade/complicações , Transtornos de Ansiedade/diagnóstico , Baclofeno/farmacologia , Agonistas GABAérgicos/farmacologia , Dependência de Heroína/complicações , Humanos , Inativação Metabólica , Masculino , Escalas de Graduação Psiquiátrica , Receptores de GABA/efeitos dos fármacos
18.
Psychiatry Res ; 66(1): 33-43, 1997 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9061802

RESUMO

Aggressiveness was experimentally induced in 30 psychophysically healthy male subjects, 18-19 years old, divided into 15 cases with low normal and 15 with high normal basal aggressivity. Plasma norepinephrine (NE), epinephrine (EPI), growth hormone (GH), prolactin (PRL), cortisol (CORT) and testosterone (Te) concentrations were measured in basal conditions and during experimentally induced aggressiveness. Basal Te and stimulated NE, GH and Cort levels were higher in subjects with high-normal than in those with low-normal aggressiveness, suggesting that the functional tonus of the NE system and of the NE-dependent hormonal axes might be a modulator of the behavioral parameter.


Assuntos
Agressão , Neurotransmissores/sangue , Personalidade , Adolescente , Adulto , Cromatografia Líquida de Alta Pressão , Frequência Cardíaca , Humanos , Masculino , Determinação da Personalidade
19.
Int J Psychophysiol ; 28(1): 99-111, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9506313

RESUMO

A variety of studies reported psychological and physiological effects of music. Different types of music have been found to induce different neuroendocrine changes. The aim of the present experiment was to investigate the possible combination of emotional and endocrine changes in response to techno-music and to define personality variables as predictors of respective changes. Sixteen psychosomatically healthy subjects (18- to 19-year-olds, eight males and eight females) were exposed, in random order, to techno-music or to classical music (30 min each). Plasma norepinephrine (NE), epinephrine (EPI), growth hormone (GH), prolactin (PRL), adrenocorticotropic hormone (ACTH) cortisol (CORT), beta-endorphin (beta-EP) concentrations and changes of emotional state were measured in basal conditions and after the experimental trials with two different types of music. Techno-music was associated with a significant increase in heart rate, systolic blood pressure and significant changes in self-rated emotional states. A significant increase was observed in beta-EP, ACTH, NE, GH and CORT after listening to techno-music. Classical music induced an improvement in emotional state, but no significant changes in hormonal concentrations. No differences between male and female subjects' responses to music have been found. Plasma levels of PRL and EPI were unaffected by techno- and classical music. Changes in emotional state and NE, beta-EP and GH responses to techno-music correlated negatively with harm avoidance scores and positively with the novelty-seeking temperament score on the Cloninger scale. Listening to techno-music induces changes in neurotransmitters, peptides and hormonal reactions, related to mental state and emotional involvement: personality traits and temperament may influence the wide inter-individual variability in response to music.


Assuntos
Emoções/fisiologia , Música , Sistemas Neurossecretores/fisiologia , Personalidade/fisiologia , Adolescente , Pressão Sanguínea/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Hormônios/sangue , Humanos , Masculino , Testes de Personalidade
20.
Rev Assoc Med Bras (1992) ; 44(4): 273-6, 1998.
Artigo em Português | MEDLINE | ID: mdl-9852645

RESUMO

BACKGROUND: To define the normal values of amniotic fluid alphafetoprotein in pregnant women, whose gestational ages range from 14 to 21 weeks, in the Hospital de Clínicas de Porto Alegre. MATERIAL AND METHOD: One hundred thirty seven women with indication for amniocentesis were studied. The alphafetoprotein was measured in all samples using enzyme immunoassay. One hundred and nine normal pregnancies were selected. All of these fetuses had normal karyotype and had no malformation. They were not twins and their amniotic fluid samples were not bloody. These samples were divided by their gestational ages. Then the medians of the alphafetoprotein values and their multiples were calculated. RESULTS: The medians of alphafetoprotein (KUI/ml) for each gestational age were as follows: 14 weeks: 16.32; 15 weeks: 14.36; 16 weeks: 13.43; 17 weeks: 10.93; 18 weeks: 8.22; 19 weeks: 7.35; 20 weeks: 5.62; 21 weeks: 4.47. CONCLUSION: The establishment of alphafetoprotein normal values in our service allows us to use this assay for patients at risk of neural tube defects. It also makes possible to analyze samples sent for cytogenetic or metabolic studies, in order to identify elevated levels of alphafetoprotein, so that these fetuses could have a more detailed sonography study to look for malformations.


Assuntos
Líquido Amniótico/química , alfa-Fetoproteínas/análise , Adulto , Amniocentese , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Segundo Trimestre da Gravidez , Valores de Referência
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