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1.
J Fish Biol ; 92(5): 1590-1603, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29624686

RESUMO

Migration of wild and cultivated juvenile honmoroko Gnathopogon caerulescens of from the spawning and nursery areas in Lake Biwa were investigated, both in the Ibanaiko Lagoon and its outlet to Daido River, using beam-trawl surveys in 2013 and 2014. The study demonstrated migration of G. caerulescens from a nursery lagoon toward Lake Biwa after the juvenile stage. These findings appear to be the first direct evidence for migration of an exclusively pelagic cyprinid species from a littoral nursery to a pelagic adult habitat in a large deep lake.


Assuntos
Migração Animal , Cyprinidae/fisiologia , Animais , Cyprinidae/crescimento & desenvolvimento , Ecossistema , Japão , Lagos , Rios
2.
J Pharm Biomed Anal ; 153: 126-134, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29477928

RESUMO

The present contribution aims to design new-generation bar adsorptive microextraction (BAµE) devices that promote an innovative and much better user-friendly analytical approach. The novel BAµE devices were lab-made prepared having smaller dimensions by using flexible nylon-based supports (7.5 × 1.0 mm) coated with convenient sorbents (≈ 0.5 mg). This novel advance allows effective microextraction and back-extraction ('only single liquid desorption step') stages as well as interfacing enhancement with the instrumental systems dedicated for routine analysis. To evaluate the achievements of these improvements, four antidepressant agents (bupropion, citalopram, amitriptyline and trazodone) were used as model compounds in aqueous media combined with liquid chromatography (LC) systems. By using an N-vinylpyrrolidone based-polymer phase good selectivity and efficiency were obtained. Assays performed on 25 mL spiked aqueous samples, yielded average recoveries in between 67.8 ±â€¯12.4% (bupropion) and 88.3 ±â€¯12.1% (citalopram), under optimized experimental conditions. The analytical performance also showed convenient precision (RSD < 12%) and detection limits (50 ng L-1), as well as linear dynamic ranges (160-2000 ng L-1) with suitable determination coefficients (r2 > 0.9820). The application of the proposed analytical approach on biological fluids showed negligible matrix effects by using the standard addition methodology. From the data obtained, the new-generation BAµE devices presented herein provide an innovative and robust analytical cycle, are simple to prepare, cost-effective, user-friendly and compatible with the current LC autosampler systems. Furthermore, the novel devices were designed to be disposable and used together with negligible amounts of organic solvents (100 µL) during back-extraction, in compliance with the green analytical chemistry principles. In short, the new-generation BAµE devices showed to be an eco-user-friendly approach for trace analysis of priority compounds in biological fluids and a versatile alternative over other well-stablished sorption-based microextraction techniques.


Assuntos
Antidepressivos/química , Microextração em Fase Líquida/métodos , Microextração em Fase Sólida/métodos , Adsorção , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Polímeros/química , Solventes/química , Água/química
3.
J Pharm Biomed Anal ; 129: 593-599, 2016 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-27519155

RESUMO

In this study, the enhancement for trace analysis of sulfonamide antibiotics (sulfathiazole, sulfamethoxazole and sulfadimethoxine) and trimethoprim in water matrices is proposed using bar adsorptive microextraction combined with micro-liquid desorption followed by high-performance liquid chromatography with diode array detection (BAµE-µLD/HPLC-DAD). By comparing different polymers and activated carbons as sorbent coatings for BAµE, the polystyrene-divinylbenzene polymer (PS-DVB) showed the best selectivity for the compounds under study. Assays performed through BAµE(PS-DVB)-µLD on 25mL of ultrapure water samples spiked at the 8.0µgL(-1) level showed recoveries ranging from 63.8±1.5% to 84.2±1.9%, under optimized experimental conditions. The validated method provided satisfactory limits of detection (0.08-0.16µgL(-1)) and good linear dynamic ranges (0.16-8.00µgL(-1)) with determination coefficients higher than 0.9958. The proposed analytical methodology was applied to real matrices, such as tap, estuarine and wastewater samples using the standard addition method. It showed to be easy to implement, with good reproducibility, sensitivity and requiring small amount of sample. Furthermore, negligible consumption of organic solvents was used in compliance with the green analytical chemistry principles. When compared to other well-established microextraction approaches, BAµE demonstrated better performance concerning recovery yields and sensitivity.


Assuntos
Antibacterianos/química , Sulfanilamidas/química , Águas Residuárias/análise , Água/química , Adsorção , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Reprodutibilidade dos Testes , Microextração em Fase Sólida/métodos , Sulfanilamida , Poluentes Químicos da Água/química
4.
J Theor Biol ; 386: 55-61, 2015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26382230

RESUMO

A leading edge vortex exists on the upper surface of an autorotating plant seed. The vortex enhances the vertical aerodynamic force acting on the seed and decreases the rate of descent. We analyzed the flight data of rotary seeds and revealed that the lift-drag ratio affects the descent factor more strongly than the vertical force coefficient. This has also been confirmed by falling tests of model rotors, which have various aspect ratios, airfoil shapes and total masses.


Assuntos
Modelos Biológicos , Rotação , Sementes/fisiologia , Algoritmos , Fenômenos Biomecânicos , Reologia , Sementes/anatomia & histologia , Árvores/anatomia & histologia , Árvores/fisiologia
5.
Chemosphere ; 135: 257-64, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25965005

RESUMO

We aimed to evaluate the ecological integrity of a large river, which receives agricultural and urban effluents and is used to water public supply. The fish species Astyanax bifasciatus was used as bioindicator during winter and spring 2012, and summer 2013 at the Middle Iguaçu River basin in Paraná state, Brazil. Water chemical and physical measures and ecotoxicological tests were carried out as well biochemical and genetic biomarkers in sampled fish in each period. The studied area was divided in three sample points: SP1, located where the water is collected to public supply; SP2, located in an urbanized area, and SP3, located at an urbanized area with the discharge of the sewage treatment. Although water chemical and physical analyzes were range of the Brazilian law to hydric bodies, anticholinesterasic effects were found in winter, oxidative stress in summer and spring. The higher genotoxic effect was in winter to all sample points. The temporal variation in biomarkers and the detection of caffeine in the water call attention to the water quality in this river mainly to be used to public supply.


Assuntos
Monitoramento Ambiental/métodos , Peixes/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Brasil , Rios , Estações do Ano , Água , Poluentes Químicos da Água/análise , Qualidade da Água , Abastecimento de Água
6.
Eur Psychiatry ; 25(7): 409-13, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20427155

RESUMO

OBJECTIVE: The objective of this study was to explore factors associated with hara-kiri as a method of suicide and suicidal behavior in contemporary Japan. METHODS: A retrospective study was conducted on medical records of 421 patients (174 male; 247 female) who were considered suicidal and treated at the Kitasato University Hospital Emergency Medical Center in Japan between January 2006 and March 2008. We compared hara-kiri and all other methods regarding sociodemographics and clinical features of all suicidal patients. RESULTS: Instances of hara-kiri suicide attempt had the highest proportion of males (63%) among all suicide and suicidal behavior. One-way analysis of variance revealed significant differences between hara-kiri and other suicide attempt methods in the age of the suicidal patients. Result of multiple logistic regression analysis indicated that those who attempted hara-kiri suicide were likely to be male, be diagnosed with schizophrenia, survive, and be married. CONCLUSION: Our findings indicate that hara-kiri as a method of suicide and suicidal behavior remains prevalent in Japan, and the study findings also suggest that both clinical and cultural factors might play a role in hara-kiri as a method of suicide and suicidal behavior.


Assuntos
Transtornos Mentais/psicologia , Tentativa de Suicídio/psicologia , Suicídio/psicologia , Fatores Etários , Análise de Variância , Feminino , Humanos , Japão , Modelos Logísticos , Masculino , Estado Civil , Prontuários Médicos , Escalas de Graduação Psiquiátrica , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais
7.
J Neural Eng ; 7(1): 16008, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20083862

RESUMO

Neurons cultured on multielectrode arrays almost always lack external stimulation except during the acute experimental phase. We have investigated the effects of chronic stimulation during the course of development in cultured hippocampal neural networks by applying paired pulses at half of the electrodes for 0, 1 or 3 r/day for 8 days. Spike latencies increased from 4 to 16 ms as the distance from the stimulus increased from 200 to 1700 microm, suggesting an average of four synapses over this distance. Compared to no chronic stimulation, our results indicate that chronic stimulation increased evoked spike counts per stimulus by 50% at recording sites near the stimulating electrode and increased the instantaneous firing rate. On trials where both pulses elicited responses, spike count was 40-80% higher than when only one of the pulses elicited a response. In attempts to identify spike amplitude plasticity, we found mainly amplitude variation with different latencies suggesting recordings from neurons with different identities. These data suggest plastic network changes induced by chronic stimulation that enhance the reliability of information transmission and the efficiency of multisynaptic network communication.


Assuntos
Potenciais de Ação/fisiologia , Estimulação Elétrica/métodos , Potenciais Evocados/fisiologia , Hipocampo/fisiologia , Neurônios/fisiologia , Sinapses/fisiologia , Animais , Células Cultivadas , Microeletrodos , Plasticidade Neuronal/fisiologia , Probabilidade , Ratos , Processamento de Sinais Assistido por Computador , Fatores de Tempo
8.
J Small Anim Pract ; 50(11): 568-74, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19814769

RESUMO

OBJECTIVES: To define the outcome of a cohort of canine patients with a histological diagnosis of spindle cell tumour of soft tissue managed solely by surgery in first opinion practice. METHODS: Clinical details of 104 spindle cell sarcomas submitted to Finn Pathologists during the year 2000 were reviewed. Questionnaires were sent to the submitting veterinarians, requesting details about the tumour, surgery performed and ultimate outcome of the patient. RESULTS: The method of surgical resection was described as marginal in 45 dogs (44.2 per cent). Excision margins of 3 cm or more were described in less than 10 per cent of cases. Tumours recurred locally in 29 dogs (27.9 per cent). Eighteen dogs (21.7 per cent) died of tumour-related causes. Most deaths were unrelated to sarcoma (50 dogs, 60.2 per cent) or unknown (15 dogs, 18 per cent). The median survival time was 1013 days. Tumour size, location or degree of surgical resection were not significantly related to survival or tumour recurrence. A palpable assessment of tumour invasion into underlying tissues was significantly associated with decreased disease-free interval (P<0.0001) and survival time (P = 0.0070). CLINICAL SIGNIFICANCE: The results of this retrospective study indicate that many spindle cell tumours managed in first opinion practice exhibit a low-grade biological behaviour and may respond well to more conservative surgery than current recommendations advise.


Assuntos
Doenças do Cão/cirurgia , Sarcoma/veterinária , Neoplasias de Tecidos Moles/veterinária , Animais , Estudos de Coortes , Intervalo Livre de Doença , Doenças do Cão/mortalidade , Doenças do Cão/patologia , Cães , Extremidades , Feminino , Estimativa de Kaplan-Meier , Masculino , Invasividade Neoplásica , Recidiva Local de Neoplasia/veterinária , Estudos Retrospectivos , Sarcoma/mortalidade , Sarcoma/patologia , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/mortalidade , Neoplasias de Tecidos Moles/patologia , Neoplasias de Tecidos Moles/cirurgia , Resultado do Tratamento
9.
J Neural Eng ; 6(1): 014001, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19104141

RESUMO

Neuronal network output in the cortex as a function of synapse density during development has not been explicitly determined. Synaptic scaling in cortical brain networks seems to alter excitatory and inhibitory synaptic inputs to produce a representative rate of synaptic output. Here, we cultured rat hippocampal neurons over a three-week period to correlate synapse density with the increase in spontaneous spiking activity. We followed the network development as synapse formation and spike rate in two serum-free media optimized for either (a) neuron survival (Neurobasal/B27) or (b) spike rate (NbActiv4). We found that while synaptophysin synapse density increased linearly with development, spike rates increased exponentially in developing neuronal networks. Synaptic receptor components NR1, GluR1 and GABA-A also increase linearly but with more excitatory receptors than inhibitory. These results suggest that the brain's information processing capability gains more from increasing connectivity of the processing units than increasing processing units, much as Internet information flow increases much faster than the linear number of nodes and connections.


Assuntos
Neurônios/fisiologia , Sinapses/fisiologia , Potenciais de Ação , Análise de Variância , Animais , Células Cultivadas , Hipocampo/fisiologia , Imuno-Histoquímica , Microeletrodos , Ratos , Receptores de AMPA/metabolismo , Receptores de GABA-A/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Sinaptofisina/metabolismo
10.
J Appl Toxicol ; 29(1): 15-9, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18651722

RESUMO

We previously reported a 65-year-old man who aspirated an alkaline detergent containing 3.3% w/v (weight of solute per volume of solution) monoethanolamine (MEA) into his lungs, causing asthma-like symptoms. We presently describe the mechanism of MEA-induced bronchoconstriction according to findings in guinea pigs. In anesthetized, artificially ventilated animals, changes in airway opening pressure (P(ao)) were measured as an index of bronchoconstriction. An aerosol of 3.3% MEA solution (0.1 ml kg(-1)) inhaled through a tracheal cannula induced significantly stronger bronchoconstriction than an aerosol of potassium hydroxide (KOH) solution (0.1 ml kg(-1)) at the same pH. MEA-induced bronchoconstriction was significantly suppressed by premedication with intravenously injected atropine sulfate (3 mg kg(-1)), a muscarinic receptor antagonist, or diphenhydramine hydrochloride (10 mg kg(-1)), a histamine-H(1) receptor antagonist. MEA-induced bronchoconstriction was not enhanced by premedication with an intravenous injection of neostigmine (0.1 mg kg(-1)), an acetylcholinesterase inhibitor. When bronchoconstriction was induced by MEA, histamine concentrations in bronchoalveolar lavage fluid (BALF) were not significantly greater than in BALF after KOH-induced bronchoconstriction or in BALF after inhalation of physiologic saline. In vitro, contraction of trachea denuded of epithelium during superfusion with MEA (10 mm) was suppressed by premedication with pyrilamine maleate, a histamine-H(1) receptor antagonist, at 10 and 100 microm. Contraction of trachea denuded of epithelium during superfusion with MEA (10 mm) was suppressed by premedication with atropine sulfate at 10 and 100 microm. These results suggest that asthma-like symptoms may result partly from agonistic MEA effects at histamine-H(1) receptors and muscarinic receptors.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Obstrução das Vias Respiratórias/induzido quimicamente , Asma/induzido quimicamente , Broncoconstrição/efeitos dos fármacos , Etanolamina/toxicidade , Aerossóis , Obstrução das Vias Respiratórias/fisiopatologia , Resistência das Vias Respiratórias/efeitos dos fármacos , Animais , Asma/fisiopatologia , Atropina/farmacologia , Líquido da Lavagem Broncoalveolar/química , Broncoconstrição/fisiologia , Broncodilatadores/farmacologia , Difenidramina/farmacologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Interações Medicamentosas , Etanolamina/administração & dosagem , Cobaias , Histamina/análise , Exposição por Inalação , Intubação Intratraqueal , Masculino , Neostigmina/farmacologia , Técnicas de Cultura de Órgãos , Traqueia/efeitos dos fármacos , Traqueia/fisiopatologia
12.
Intern Med ; 40(3): 246-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11310493

RESUMO

A 69-year-old woman with idiopathic thrombocytopenic purpura, who was regularly followed and treated with prednisolone and danazol, was admitted to our hospital because of shortness of breath. Chest roentgenogram showed a large amount of left-sided pleural effusion. Gram-positive branching rods, subsequently identified as Nocardia farcinica, were isolated from the fluid. Antibiotic treatment together with pleural drainage with an intercostal catheter resulted in complete remission of pyothorax. Pulmonary nocardiosis is a rare disease, but recognition of the disease in immunocompromised patients and the prompt initiation of appropriate treatments based on isolation of the pathogen can lead to a successful outcome.


Assuntos
Nocardiose/etiologia , Púrpura Trombocitopênica Idiopática/complicações , Idoso , Cilastatina/uso terapêutico , Empiema Pleural/complicações , Empiema Pleural/patologia , Empiema Pleural/terapia , Feminino , Humanos , Imipenem/uso terapêutico , Nocardia/isolamento & purificação , Nocardiose/patologia , Nocardiose/terapia , Inibidores de Proteases/uso terapêutico , Tienamicinas/uso terapêutico , Tórax/patologia
13.
Brain Res ; 890(2): 330-2, 2001 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-11164799

RESUMO

The postcentral sulcus has two fissurization patterns: (I) the sulcus extends continuously into the sylvian fissure; (II) the sulcus is interrupted in its trajectory. In the left but not in the right hemisphere, there was a sex difference in the distribution of these fissural patterns, type I being more frequent in men and type II being more frequent in women. No hemispheric asymmetry was found for these patterns in either sex.


Assuntos
Lateralidade Funcional/fisiologia , Caracteres Sexuais , Córtex Somatossensorial/anatomia & histologia , Adulto , Idoso , Feminino , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Pessoa de Meia-Idade , Córtex Somatossensorial/fisiologia , Percepção Espacial/fisiologia , Comportamento Verbal/fisiologia
14.
Thyroid ; 11(11): 1055-61, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11762716

RESUMO

Medullary thyroid carcinoma (MTC) arises from parafollicular or C cells of the thyroid gland and produces a variety of peptides such as calcitonin (CT) and gastrin-releasing peptide (GRP). Here we measured serum levels of pro-gastrin-releasing peptide (Pro-GRP), a more stable precursor of GRP, in 15 patients with MTC (4 males, 11 females) who did not show any clinical or radiologic signs of small cell lung cancer. Serum Pro-GRP levels were elevated in 80% (12/15) patients. Significant correlation was observed between serum Pro-GRP and CT (r = 0.52) and carcinoembryonic antigen (CEA) (r = 0.56). Serum Pro-GRP levels also correlated with tumor size (r = 0.70). Serum Pro-GRP levels also decreased below the cut-off range in one patient after surgical resection. Our data suggest that Pro-GRP, which is considered to be a specific marker for small cell lung carcinoma, seems to be also helpful and additional marker for the diagnosis and monitoring the response to therapy in patients with MTC in addition to calcitonin as the main tumor marker.


Assuntos
Carcinoma Medular/sangue , Carcinoma de Células Pequenas/sangue , Peptídeos/sangue , Precursores de Proteínas/sangue , Neoplasias da Glândula Tireoide/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Calcitonina/sangue , Antígeno Carcinoembrionário/sangue , Carcinoma Medular/cirurgia , Carcinoma de Células Pequenas/cirurgia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Radioimunoensaio , Neoplasias da Glândula Tireoide/cirurgia
15.
Thyroid ; 10(11): 975-9, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11128725

RESUMO

Thirty-two patients with differentiated thyroid carcinomas with distant metastasis were examined using a radioactive iodine (131I) tracer dose prior to 131I therapy and followed up for 10 years or until death (whichever occurred first). Nineteen patients who received 131I therapy had an accumulation of 131I in the metastases (group I) and 15 of those patients were alive more than 10 years after the first 131I treatment. In contrast, all 13 patients in whom the metastases did not show accumulation of 131I died within 10 years. Of the latter group, eight patients had received 131I therapy (group II), four of whom died with anaplastic changes within 5 years of treatment. p53 gene mutation was identified by immunohistochemistry in primary thyroid carcinoma tissue from patients with anaplastic changes that were evident during total thyroidectomy. Five patients did not receive 131I therapy (group III), of whom one, who also had a p53 gene mutation in the original tumor, died with anaplastic change 10 years after thyroidectomy. Seven patients in group I had p53 gene mutations in their thyroid carcinoma tissues, but none showed anaplastic changes. Our results suggest that 131I therapy may be useful for patients with distant metastases, with or without p53 gene mutations, which show accumulation of 131I from tracer and therapeutic doses. In contrast, 131I therapy is apparently not effective in patients who do not show sufficient accumulation of 131I, but rather, may cause early anaplastic changes with a p53 gene mutation.


Assuntos
Carcinoma Papilar/radioterapia , Carcinoma Papilar/secundário , Radioisótopos do Iodo/uso terapêutico , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/secundário , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Carcinoma Papilar/genética , Diferenciação Celular , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mutação/efeitos da radiação , Radioterapia/normas , Neoplasias da Glândula Tireoide/genética , Proteína Supressora de Tumor p53/análise
16.
J Lab Clin Med ; 136(5): 344-54, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11079461

RESUMO

Humoral factors produced by activated T cells are thought to be important in the development of bone loss in patients with rheumatoid arthritis (RA). We investigated the inhibitory effect of etidronate disodium (EHDP) on apoptosis of human osteoblasts induced by supernatants from in vitro activated T cell cultures. Human osteoblastic cell line MG63 cells and human primary osteoblast-like cells were used in the present study as human osteoblasts. T cells were incubated with interleukin-2 and further activated with 1 2-o-tetradecanoyl-phorbol 13-acetate and ionomycin, either in the presence or absence of EHDP. After we carried out the cultivation, we examined the cytotoxicity of cultured T cell supernatants toward MG63 cells and human primary osteoblast-like cells. Supernatants from activated but not resting T cell cultures efficiently induced apoptosis of MG63 cells and primary osteoblast-like cells. Supernatants from activated T cell cultures, incubated with EHDP, exhibited significantly less cytotoxicity than did supernatants incubated in the absence of EHDP. In contrast, the cytotoxicity of activated T cell culture supernatants was not affected by direct treatment of human osteoblasts with EHDP. The concentration of soluble Fas ligand in activated T cell culture supernatants was actually increased by EHDP. However, EHDP did not influence soluble Fas and tumor necrosis factor-alpha concentrations in the supernatant. Furthermore, treatment of human osteoblasts with EHDP did not alter their expression of Bcl-2/Bcl-xL or their sensitivity to anti-Fas immunoglobulin M-induced apoptosis. Our results suggest that EHDP inhibits the production of soluble factor that induces apoptosis of human osteoblasts and thus exhibits a protective action toward human osteoblast apoptosis induced by activated T cell culture supernatants. Although the exact EHDP-regulated molecule that induces apoptosis of human osteoblasts is unknown at present, our study may explain part of the therapeutic action of bisphosphonates in RA complicated by bone loss.


Assuntos
Apoptose/efeitos dos fármacos , Ácido Etidrônico/farmacologia , Ativação Linfocitária , Osteoblastos/efeitos dos fármacos , Linfócitos T/fisiologia , Linhagem Celular , Humanos , Fator de Necrose Tumoral alfa/farmacologia
17.
Thyroid ; 10(8): 641-6, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11014307

RESUMO

Leptin is a protein product of the ob gene, mainly produced by adipocytes. Leptin is thought to play an important role in the homeostasis of body weight by suppressing appetite and increasing energy consumption. The aim of this study was to investigate the possible effect of thyroid hormone on the regulation of the leptin system during suppression of beta-adrenergic receptors in Graves' patients. We studied 15 adult female patients with Graves' disease. Thyroid function, serum levels of leptin, and percent body fat (%BF) were examined at four different clinical conditions during therapy (A, untreated; B, beta-adrenergic antagonist only [A, B; hyperthyroid], C, beta-adrenergic antagonist and antithyroid drug; D, antithyroid drug only [C, D; euthyroid]). The use of beta-adrenergic antagonist significantly reduced heart rate in spite of hyperthyroid state, indicating sufficient suppression of beta-adrenergic receptors. During treatment with beta-adrenergic antagonist, leptin percentage of body fat (%BF) ratio significantly decreased in euthyroid state compared to that in hyperthyroid state (from 38.7 +/- 21.3 to 18.1 +/- 19.3, p = 0.003). Moreover, there was a significantly positive correlation between delta leptin/%BF and delta free thyroxine (FT4) (r = 0.51, p = 0.008). Under a euthyroid state induced by antithyroid drug treatment, leptin/%BF did not change in spite of withdrawal of beta-adrenergic antagonist. Our data indicate that thyroid hormones could increase serum leptin level during suppression of beta-adrenergic receptors in Graves' patients. Our data also suggest that the beta-adrenergic action of thyroid hormones might be partly mediated by regulation of leptin.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Doença de Graves/sangue , Leptina/sangue , Tiroxina/fisiologia , Antagonistas Adrenérgicos beta/farmacologia , Adulto , Idoso , Feminino , Doença de Graves/tratamento farmacológico , Humanos , Pessoa de Meia-Idade
18.
Thyroid ; 10(7): 595-9, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10958312

RESUMO

The use of propylthiouracil (PTU) for the treatment of Graves' disease is associated with few adverse effects such as skin eruptions, liver dysfunction, and agranulocytosis. Furthermore, recent studies described the development of antineutrophil cytoplasmic antibody (ANCA)-related glomerulonephritis and vasculitis in patients treated with PTU. Here we investigated whether PTU therapy per se is associated with the appearance of ANCA in patients with Graves' disease. We analyzed 119 serum samples from 117 patients with Graves' disease treated with either PTU (n = 56), or methimazole (MMI) (n = 21), as well as untreated patients (n = 42). Myeloperoxidase (MPO)-ANCA and proteinase 3 (PR3)-ANCA were tested by enzyme-linked immunosorbent assay (ELISA) kits. MPO-ANCA was negative in all patients treated with MMI therapy and untreated patients. However, MPO-ANCA was detected in 21 (37.5%) of 56 patients treated with PTU therapy. Furthermore, two patients who were negative for MPO-ANCA became positive after PTU therapy. The proportion of patients positive for MPO-ANCA increased with the prolongation of PTU therapy, but did not correlate with age, gender, and positive antithyroperoxidase (TPO) antibody. Among 21 MPO-ANCA positive patients, 12 had no symptoms, but 9 patients complained of myalgia, arthralgia, or common cold like symptoms after the appearance of MPO-ANCA. Three patients developed agranulocytosis or granulocytopenia, but none showed abnormal urinary findings. Our results suggest that PTU per se is associated with the production of MPO-ANCA in patients with Graves' disease.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos/sangue , Antitireóideos/efeitos adversos , Doença de Graves/tratamento farmacológico , Propiltiouracila/efeitos adversos , Adulto , Idoso , Agranulocitose/imunologia , Antitireóideos/uso terapêutico , Autoanticorpos/sangue , Feminino , Doença de Graves/imunologia , Humanos , Iodeto Peroxidase/imunologia , Masculino , Pessoa de Meia-Idade , Mieloblastina , Peroxidase/imunologia , Propiltiouracila/uso terapêutico , Serina Endopeptidases/imunologia
20.
Clin Endocrinol (Oxf) ; 52(2): 203-9, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10671948

RESUMO

OBJECTIVE: Osteopenia is an important feature of primary hyperparathyroidism (PHP). However, little is known about the change of bone mineral density (BMD) in PHP after surgery. The aim was to investigate the mechanisms of increased BMD after parathyroidectomy in patients with PHP. DESIGN: Prospective observational study. PATIENTS: Ten patients with PHP (7 women, 3 men; mean age 53.2+/-9.1 years). All patients underwent parathyroidectomy for excision of parathyroid adenoma. MEASUREMENTS: BMDs of two cancellous bone-rich sites (L2-L4 lumbar spine and ultra-distal end of the radius, RUD) and one cortical bone-rich site (distal third of the radius, R33%) were measured using dual energy X-ray absorptiometry, before, and 3, 6 and 12 months after surgery. Serum intact PTH, intact osteocalcin, bone type alkaline phosphatase (b-ALP), alkaline phosphatase, calcium, and urinary deoxypyridinoline (Dpd) were measured before, and 1 and 3 days, and 1, 2, 3, 4, 6, 8, 12, and 24 weeks after surgery. RESULTS: Parathyroidectomy resulted in a significant increase in BMDs of L2-L4 and RUD at 3 months postoperatively. Urinary Dpd levels decreased within a few days after surgery, while b-ALP and osteocalcin decreased more slowly throughout the first few months after surgery. The ratio of osteocalcin/Dpd at 1 week after surgery correlated significantly with the percentage change in BMD of L2-L4 at 3 and 6 months after surgery. The ratio of osteocalcin/Dpd at 2 weeks correlated significantly with the percentage change in BMD of L2-L4 at 3, 6 and 12 months after surgery. The preoperative values of osteocalcin, b-ALP, PTH and calcium were positively correlated with the change in BMD of RUD at 3 months and L2-L4 at 12 months, RUD at 6 months, RUD at 3 months and L2-L4 at 12 months, respectively. CONCLUSIONS: In primary hyperparathyroidism patients, the major increase in bone mineral density following parathyroidectomy occurs within 3 months. Parathyroidectomy resulted in a marked increase in bone mineral density of cancellous bones compared to that of cortical bones. The early increase in bone mineral density was due to a preferential activation of bone formation over bone resorption as evidenced by changes in bone metabolic markers. Our results also showed that the preoperative levels of bone metabolic markers may predict the gain in bone mineral density after parathyroidectomy.


Assuntos
Densidade Óssea , Hiperparatireoidismo/fisiopatologia , Hiperparatireoidismo/cirurgia , Paratireoidectomia , Adenoma/fisiopatologia , Adenoma/cirurgia , Adulto , Fosfatase Alcalina/sangue , Aminoácidos/urina , Biomarcadores/sangue , Biomarcadores/urina , Remodelação Óssea , Cálcio/sangue , Feminino , Humanos , Hiperparatireoidismo/metabolismo , Masculino , Pessoa de Meia-Idade , Osteocalcina/sangue , Hormônio Paratireóideo/sangue , Neoplasias das Paratireoides/fisiopatologia , Neoplasias das Paratireoides/cirurgia , Período Pós-Operatório , Estudos Prospectivos
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