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2.
Med Phys ; 42(1): 400-11, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25563280

RESUMO

PURPOSE: The response of alanine solid state dosimeters to ionizing radiation strongly depends on particle type and energy. Due to nuclear interactions, neutron fields usually also consist of secondary particles such as photons and protons of diverse energies. Various experiments have been carried out in three different neutron beams to explore the alanine dose response behavior and to validate model predictions. Additionally, application in medical neutron fields for boron neutron capture therapy is discussed. METHODS: Alanine detectors have been irradiated in the thermal neutron field of the research reactor TRIGA Mainz, Germany, in five experimental conditions, generating different secondary particle spectra. Further irradiations have been made in the epithermal neutron beams at the research reactors FiR 1 in Helsinki, Finland, and Tsing Hua open pool reactor in HsinChu, Taiwan ROC. Readout has been performed with electron spin resonance spectrometry with reference to an absorbed dose standard in a (60)Co gamma ray beam. Absorbed doses and dose components have been calculated using the Monte Carlo codes fluka and mcnp. The relative effectiveness (RE), linking absorbed dose and detector response, has been calculated using the Hansen & Olsen alanine response model. RESULTS: The measured dose response of the alanine detector in the different experiments has been evaluated and compared to model predictions. Therefore, a relative effectiveness has been calculated for each dose component, accounting for its dependence on particle type and energy. Agreement within 5% between model and measurement has been achieved for most irradiated detectors. Significant differences have been observed in response behavior between thermal and epithermal neutron fields, especially regarding dose composition and depth dose curves. The calculated dose components could be verified with the experimental results in the different primary and secondary particle fields. CONCLUSIONS: The alanine detector can be used without difficulty in neutron fields. The response has been understood with the model used which includes the relative effectiveness. Results and the corresponding discussion lead to the conclusion that application in neutron fields for medical purpose is limited by its sensitivity but that it is a useful tool as supplement to other detectors and verification of neutron source descriptions.


Assuntos
Alanina/efeitos da radiação , Terapia por Captura de Nêutron de Boro/instrumentação , Nêutrons/uso terapêutico , Radiometria/instrumentação , Terapia por Captura de Nêutron de Boro/métodos , Radioisótopos de Cobalto/uso terapêutico , Simulação por Computador , Relação Dose-Resposta à Radiação , Espectroscopia de Ressonância de Spin Eletrônica , Raios gama/uso terapêutico , Modelos Teóricos , Método de Monte Carlo , Fótons , Prótons , Radiometria/métodos
3.
Climacteric ; 16(3): 381-6, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22963154

RESUMO

AIM: To examine the relationships between depressive symptoms, menopausal status, and menopausal symptoms in middle-aged women. MATERIAL AND METHODS: This cross-sectional, population-based study involved patients in the Taiwanese community. Data were retrieved from the nationwide 2002 Health Promotion Knowledge, Attitude, and Performance Survey in Taiwan. We assessed depressive symptoms using the Taiwanese Depression Questionnaire with a cut-off point of 18 of 19. Self-reported perception of menopausal status, frequency of menstrual periods in the preceding 12 months, and a history of oophorectomy surgery were used to categorize the women's menopausal status into premenopause, perimenopause, postmenopause, and surgical menopause. RESULTS: A total of 3359 women aged 40-55 years were selected. Among these patients, 145 women (4.7%) experienced higher levels of concurrent depressive symptoms. The increase in depressive symptoms was significantly associated with menopausal status and most of the menopausal symptoms. After controlling for age, marital status, education, income, smoking, hormone therapy, and menopause symptoms, multivariate logistic regression showed that perimenopause was still significantly associated with depression in midlife women (odds ratio 1.97; 95% confidence interval 1.24-3.14). CONCLUSION: Independent of menopausal symptoms, perimenopausal status increases the risk of depression.


Assuntos
Depressão/epidemiologia , Perimenopausa/psicologia , Adulto , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Renda , Estado Civil , Menopausa , Pessoa de Meia-Idade , Inquéritos e Questionários , Taiwan/epidemiologia
4.
J Hazard Mater ; 138(3): 539-42, 2006 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-16839673

RESUMO

Speciation of copper in the incineration waste heat boiler (HB) and the down stream electrostatic precipitator (EP) fly ashes during the flue gas cooling down (1123-->473 K) has been studied by X-ray absorption near edge structural (XANES) spectroscopy in the present work. Copper species such as Cu(OH)(2) (59-67%), CuCl(2) (5-12%), CuO (24-26%), and a small amount of CuS (3-4%) in fly ashes were determined by semi-quantitative analyses of the XANES spectra. In the toxicity characteristics leaching procedure (TCLP) tests, about 83 and 20% of copper were leached from the EP and HB fly ashes, respectively. The relatively high leachability of copper for the EP fly ash might be due to the fact that CuCl(2) was enriched on the surfaces as observed by X-ray photoelectron spectroscopy (XPS). On the contrary, CuCl(2) was mainly encapsulated in the HB fly ashes.


Assuntos
Carbono/química , Cobre/análise , Cobre/química , Incineração , Material Particulado/química , Cloretos/análise , Cinza de Carvão , Tamanho da Partícula , Análise Espectral , Eletricidade Estática , Difração de Raios X
7.
J Hazard Mater ; 91(1-3): 301-7, 2002 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-11900920

RESUMO

The speciation of copper and zinc in the incineration fly ash of a municipal solid waste in Taiwan was investigated in the present work. By the least-squares fitted X-ray absorption near edge structural (XANES) spectroscopy, we found that CuCO3, CuOH2, and CuO (fractions of 0.09, 0.39 and 0.51, respectively) were the main copper species in the fly ash. Quantitative analysis of the extended X-ray absorption fine structural (EXAFS) spectra indicated that the bond distance of Cu-O in the fly ash was 1.96 A with a coordination number (CN) of 3.9 in the first shell of copper. In the second shell, the bond distance and CN of Cu-(O)-Cu were 2.91 A and 2.7, respectively. In addition, speciation of Zn was also examined in the same X-ray absorption energy (8780-9970 eV). The bond distance of Zn-O and Zn-O-Zn were 1.97 and 2.94 A, respectively. However, the Zn-O-Cu structure was not found because of the physically unreasonable sigma(2) (Debye-Waller factor) values in the EXAFS data fitting process.


Assuntos
Cobre/química , Eliminação de Resíduos , Poluentes Atmosféricos/análise , Fenômenos Químicos , Físico-Química , Cidades , Incineração , Análise Espectral
8.
J Synchrotron Radiat ; 8(Pt 2): 931-3, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11512983

RESUMO

Copper species such as CuCO3, Cu(OH)2, CuS and CuO were found in the bag house and EP (electrostatic precipitator) fly ashes of waste incineration processes by X-ray absorption near edge structural (XANES) spectroscopy. A small amount of Cu(I) and metallic Cu was found in the bag house fly ash. The averaged Cu-O bond distance in the fly ashes determined by EXAFS (extended X-ray absorption fine structural) was 1.96 A with coordination numbers of 2.4-3.9. However, the Cu-(O)-Cu (2nd shell) bond distance of the fly ashes in the incineration process was decreased by 0.19-0.21 A if compared to that of the CuO standard. The coordination numbers of the 2nd shell contribution to the bag house fly ash were not very significant.


Assuntos
Carbono/análise , Cobre/análise , Incineração , Carbonatos/análise , Cinza de Carvão , Cobre/química , Análise de Fourier , Hidróxidos/análise , Material Particulado , Espectrometria por Raios X/métodos
9.
Environ Sci Technol ; 35(12): 2532-5, 2001 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-11432559

RESUMO

Speciation of copper in the fly ash solidification process has been studied by X-ray based spectroscopies inthe present work. Fourier transformed EXAFS (extended X-ray absorption fine structural) spectra of the solidified fly ashes showed that the bond distance of Cu-O (first shell) was 1.96 A with a coordination number (CN) of about 3.0. However, in the second shell of copper atoms, the bond distance of Cu-(O)-Cu was decreased by 0.12-0.22 A during solidification, which might cause the stabilization of the CuO species in the solidified fly ash matrix. By the least-squares fits of the XANES (X-ray absorption near edge structural) spectra, fractions of the main copper species in the solidified fly ashes such as CuCl2 (0.08-0.11), Cu2O (0.07-0.09), Cu(OH)2 (0.31-0.33), and CuO (0.49-0.52) were observed. Combined EXAFS and XANES observations suggested that chemical reactions such as hydroxylation of CuCl2 and oxidation of Cu2O and/or metallic Cu might involve in the solidification process, which also led to a significant reduction of the leachability of copper from the solidified fly ashes.


Assuntos
Poluentes Atmosféricos/análise , Cobre/análise , Monitoramento Ambiental/métodos , Cobre/química , Hidroxilação , Incineração , Eliminação de Resíduos , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Chin J Physiol ; 44(4): 169-79, 2001 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-11908546

RESUMO

The aim of the present study was to examine the relationship between the lateral tegmental field (FTL), a cardioinhibitory area, with other cardioinhibitory areas, i.e., the ambiguus nucleus (NA) and the dorsal motor nucleus of vagus (DMV) and the caudal ventrolateral medulla (CVLM), a vasopressor inhibitory area. In 55 cats anesthetized with chloralose (40 mg/kg) and urethane (400 mg/kg), the cardiovascular responses of heart rate (HR), systemic arterial blood pressure (SAP) and vertebral nerve activity (VNA) were recorded. The FTL, NA, DMV and CVLM were identified first by stimulation (rectangular pulses in 80 Hz, 0.5 ms, 50-100 microA) and then confirmed by microinjection of sodium glutamate (Glu, 0.25M, 70 nl). In studying the influence of NA, DMV, or CVLM lesion on the Gluinduced responses in FTL, kainic acid (KA, 24 mM, 100 nl) was microinjected into the NA, DMV or CVLM. FTL stimulation produced an average decrease of HR by 55%. After KA lesioning of the ipsilateral NA or the DMV, the decreased HR induced by FTL was significantly diminished. After subsequent lesion of the contralateral DMV or NA, the bradycardia of FTL was abolished. The reduction of resting HR was more intense after lesioning the NA than DMV and with the left side more than that of the right side. These studies suggest that the cardioinhibitory responses of FTL are mediated through both NA and DMV with predominance of the former, while the hypotensive effect of FTL is mediated through CVLM. The precise pathway responsible for the FTL-induced bradycardia and hypotension is to be determined.


Assuntos
Fenômenos Fisiológicos Cardiovasculares , Bulbo/fisiologia , Tegmento Mesencefálico/fisiologia , Nervo Vago/fisiologia , Animais , Pressão Sanguínea/fisiologia , Gatos , Estimulação Elétrica , Feminino , Sistema de Condução Cardíaco/fisiologia , Masculino , Inibição Neural/fisiologia
11.
Biochem Biophys Res Commun ; 269(1): 14-20, 2000 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-10694469

RESUMO

Penicillium notatum is a well-known indoor aeroallergen and is frequently included in skin test panels for allergic diagnosis. On two-dimensional immunoblotting using patients' sera containing IgE and monoclonal antibody D7B8 specific for Pen c 1 of P. citrinum, two allergens with a molecular mass of 33 kDa but different isoelectric points were identified. A novel cDNA coding for Pen n 13 was cloned and sequenced. The nucleotide sequence codes for a protein 397 amino acids including a putative signal peptide of 25 amino acids and a propeptide of 90 amino acids. The allergen is an alkaline serine protease that shares more than 39% identical residues with other kinds of mold allergens. The coding cDNA of Pen n 13 was cloned into vector pQE-30 and expressed in E. coli M15 as a His-tag fusion protein and purified to homogeneity. The fusion protein reacted with monoclonal antibodies of Pen c 1 and with IgE from Penicillium-allergic patients. Furthermore, it also cross-reacted strongly with IgE specific for the natural Pen c 1, indicating that similar IgE binding epitopes may exist in the allergens of P. notatum and P. citrinum. Antigenicity index plots indicated that there are several similar epitope regions of high antigenic indices in Pen c 1 and Pen n 13, corroborating that mold allergens belonging to the alkaline serine protease family possess similar protein structure and strong antigenic cross-reactivity.


Assuntos
Alérgenos/genética , Antígenos de Fungos/genética , Penicillium/genética , Penicillium/imunologia , Alérgenos/química , Sequência de Aminoácidos , Anticorpos Antifúngicos/sangue , Anticorpos Monoclonais , Antígenos de Fungos/química , Sequência de Bases , Reações Cruzadas , Primers do DNA/genética , DNA Fúngico/genética , Epitopos/química , Epitopos/genética , Humanos , Hipersensibilidade/imunologia , Ponto Isoelétrico , Dados de Sequência Molecular , Peso Molecular , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Homologia de Sequência de Aminoácidos
12.
Psychiatry Clin Neurosci ; 53(5): 575-8, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10595682

RESUMO

Ramsay Hunt syndrome (RHS) is a rare condition within the progressive myoclonic epilepsies syndrome (PME), with a triad of action myoclonus, grand mal seizure and severe cerebellar ataxia. There are few reports about the psychiatric disturbances associated with PME or RHS. The present study examines the evidence that RHS may accompany an organic mental syndrome, ethanol's effective suppression of myoclonus, and the possible resultant problem of alcohol dependence in RHS patients. Two brothers with the previous long-standing diagnosis of RHS and their mental symptoms of persecutory delusion and depression are reported, as well as the additional problem of alcohol dependence in one of them. The cerebellar dysfunction found in RHS may be associated with an underlying organic condition. Determination of the relationship between cerebellar dysfunction and psychosis in RHS will require further study. Although the mechanism of the suppression of myoclonus by alcohol remains unclear, patients should be allowed to drink socially, and alcohol consumption should not be totally prohibited. However, effective treatment of the problems of alcohol tolerance, abuse, or dependence requires the cooperation of both neurologists and psychiatrists.


Assuntos
Alcoolismo/complicações , Epilepsias Mioclônicas Progressivas/complicações , Transtornos Parkinsonianos/complicações , Adulto , Transtorno Depressivo/etiologia , Humanos , Masculino , Epilepsias Mioclônicas Progressivas/patologia , Epilepsias Mioclônicas Progressivas/psicologia , Transtornos Parkinsonianos/patologia , Transtornos Parkinsonianos/psicologia , Esquizofrenia Paranoide/etiologia
13.
Psychiatry Clin Neurosci ; 53(6): 673-6, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10687749

RESUMO

Patients who visited the psychiatric outpatient service of Chang Gung Medical Centre, Tao-Yuan, Taiwan during an 8-year period were studied retrospectively. Among the 10,418 outpatients, 86 (0.83%) were diagnosed as having DSM-IV delusional disorder (DD), including 61 (70.9%) with persecutory type, 12 (14.0%) with the mixed type, seven (8.1%) with jealous type, two (2.3%) with somatic type, two (2.1%) with unspecified type, one (1.2%) with erotomanic type, and another one with grandiose type. The ratio of women to men was 0.86. The mean age at onset was 42.4 +/- 15.41 years, with women being older than men. Thirty-seven cases (43.0%) presented with depressive symptoms at their first visit. Subjects were divided into four groups: persecutory type, jealous type, mixed type and others. There were no significant differences between the four groups in terms of gender, age at onset, time-lapse before seeking psychiatric help, the presence of hallucination or the presence of depression.


Assuntos
Esquizofrenia Paranoide/psicologia , Adulto , Idade de Início , Depressão/complicações , Depressão/psicologia , Feminino , Alucinações/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Escalas de Graduação Psiquiátrica , Estudos Retrospectivos , Esquizofrenia Paranoide/complicações , Taiwan
14.
J Med Chem ; 29(9): 1754-60, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3091832

RESUMO

The poly-gamma-glutamyl derivatives of n10-propargyl-5,8-dideazafolic acid (PDDF) with a chain length of up to five glutamate residues were synthesized from N10-propargyl-5,8-dideazapteroic acid by the solid-phase procedure. These compounds were evaluated for their antifolate activity using folate-requiring microorganisms and intact and permeabilized L1210 cells and as inhibitors of dihydrofolate reductase and thymidylate synthase derived from L. casei. The polyglutamylated derivatives of PDDF (1) were more active than the parent compound in inhibiting the growth of L. casei, thymidylate synthesis in permeabilized L1210 cells, and L. casei thymidylate synthase. Two analogues of 5,8-dideazafolic acid (2 and 3), one with a 2-butyne and another with a cyclopropylmethyl substituent at N10, were also synthesized and evaluated for their antifolate activities using the above-mentioned test systems. They were considerably less active than PDDF or its polyglutamylated derivatives. N10-Propargyl-5,8-dideazapteroyl tri-, tetra-, and pentaglutamates were equipotent with 5-fluorodeoxyuridylate as inhibitors of thymidylate synthesis in permeabilized L1210 cells. The polyglutamyl metabolites of PDDF were shown to be the most potent antifolate inhibitors of L. casei and L1210 thymidylate synthases yet described.


Assuntos
Antagonistas do Ácido Fólico/farmacologia , Ácido Fólico/análogos & derivados , Quinazolinas , Animais , Fenômenos Químicos , Química , Ácido Fólico/síntese química , Ácido Fólico/farmacologia , Antagonistas do Ácido Fólico/síntese química , Lacticaseibacillus casei/efeitos dos fármacos , Lacticaseibacillus casei/enzimologia , Lacticaseibacillus casei/crescimento & desenvolvimento , Leucemia L1210/enzimologia , Streptococcus/enzimologia , Relação Estrutura-Atividade , Timidilato Sintase/antagonistas & inibidores
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