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1.
Drug Alcohol Depend ; 128(3): 250-4, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23021515

RESUMO

BACKGROUND: Hypogonadism is common with opiate-like drug use and may contribute to cognitive abnormalities. With the increasing epidemic of HIV and substance use (SU) worldwide, it is important to understand the impact of these conditions on cognition, which may affect quality of life and possibly decrease adherence to treatment. We hypothesized that men with SU, by virtue of hypogonadism secondary to HIV and/or SU, may demonstrate impaired cognition. METHODS: We recruited men aged 18-50 from a population of low income, inner-city individuals. Details of HIV and SU status, serum blood levels of total testosterone (TT), free testosterone (FT) and estradiol (E2) were assessed. All subjects were administered ten neuropsychological tests. RESULTS: Our sample consisted of 68 men (mean age: 43.2 years (SD 5.8), African Americans: 86.6%). The recruited population was primarily from low socioeconomic status and unemployed. The mean level of TT was 553.9 ng/dL (SD 262.0), the mean level of FT was 69.5 pg/mL (SD 34.8), mean E2 was 3.2 pg/mL (SD 4.4). We found that 30.9% were hypogonadal and it was associated with higher SU. We observed some relationships between sex hormones and cognitive domains, however, after adjustment for age, drug use category, education, depression, HIV, there was no statistically significant correlation between cognitive performance and sex hormone levels. CONCLUSIONS: In this cross-sectional study of men with a high prevalence of SU and hypogonadism, endogenous levels of TT, FT or E2 were not related to cognitive performance. Other factors need to be identified which may contribute to poor cognitive function in the setting of SU.


Assuntos
Cognição/efeitos dos fármacos , Estradiol/sangue , Infecções por HIV/sangue , Hipogonadismo/sangue , Transtornos Relacionados ao Uso de Substâncias/sangue , Testosterona/sangue , Adolescente , Adulto , Análise de Variância , Cromatografia Líquida/métodos , Cognição/fisiologia , Estudos Transversais , Humanos , Masculino , Espectrometria de Massas/métodos , Pessoa de Meia-Idade , Testes Neuropsicológicos , Pobreza , Transtornos Relacionados ao Uso de Substâncias/psicologia , População Urbana
2.
Phys Chem Chem Phys ; 13(38): 17104-14, 2011 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-21869970

RESUMO

Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) investigations on the redox behavior of hemin at bare and 4,4'-thio-bis-benzene-thiolate (TBBT) covered n-GaAs (110) electrodes in dimethylsulfoxide (DMSO) revealed the high irreversibility of the electroreduction process, which appeared to be closely related to the stable adsorbed species strongly interfering with the electronic properties of the semiconducting substrate. The subsequent exploration of the hemin-modified electrodes by second harmonic generation (SHG), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) measurements pointed to significant differences between the iron protoporphyrin species adsorbed on the bare- and TBBT-GaAs (110) electrodes. Only Fe(2+) species having a flat configuration with the porphyrin plane oriented parallel to the surface were detected on GaAs, unlike the TBBT-GaAs, where Fe(2+) and Fe(3+) species having both flat and vertical adsorption positions could be observed. These differences originate from the mutual interactions between the solvent, hemin and dithiolate molecules as well as their competition for the surface sites found to play a key role in the electrochemical process under discussion.


Assuntos
Benzeno/química , Hemina/química , Compostos de Sulfidrila/química , Arsenicais/química , Espectroscopia Dielétrica , Técnicas Eletroquímicas , Eletrodos , Gálio/química , Microscopia de Força Atômica , Oxirredução , Espectroscopia Fotoeletrônica
3.
Future Oncol ; 5(8): 1211-20, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19852734

RESUMO

Cancer cachexia is a complex syndrome, affecting up to 60% of the approximately 1.4 million patients diagnosed with cancer each year in the USA. This condition is characterized by progressive deterioration of a patient's nutritional status, weight loss, anorexia, diminished quality of life and increased mortality and morbidity. Current therapy with progestational, anti-inflammatory and anabolic agents is often ineffective and has a large number of undesirable effects. The newly developed nonsteroidal selective androgen receptor modulator Ostarine has demonstrated promising results in Phase I and II clinical trials, increasing total lean body mass, enhancing functional performance and decreasing total tissue percent fat. This selective androgen receptor modulator may have the ability to perform as a potent anabolic agent with minimal side effects on other organs (prostate and hair follicles), thus presenting a new strategy in managing cancer cachexia. However, more extensive data is required before its efficacy is confirmed.


Assuntos
Amidas/farmacologia , Caquexia/tratamento farmacológico , Caquexia/etiologia , Neoplasias/complicações , Receptores Androgênicos/efeitos dos fármacos , Anilidas , Ensaios Clínicos como Assunto , Humanos
4.
Langmuir ; 25(11): 6522-31, 2009 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-19374442

RESUMO

Second harmonic generation (SHG) investigations on alpha-CN-terthiophene-thiolate-covered GaAs(110) electrodes in 1 N H2SO4 solution revealed significant changes in the rotational anisotropy of the SH response. The enhancement of the 1- and the 3-fold contributions around -250 mV suggests changes in the symmetry properties of the delocalized electron system due to an alteration of the adsorption geometry induced by the applied potentials. The analysis of the EIS data showed that in the potential region where the SH signal exhibits the more important changes the Mott-Schottky plot undergoes a pronounced shift to more negative potentials as a result of the charging of the surface states grouped about 1.06 eV below the conduction band edge. Semiempirical MO calculations suggest that the most energetically favorable interaction implies electron transfer from the semiconductor conduction band to the lowest unoccupied molecular orbital of the organic molecule with epsilon(LUMO)=-1.707 eV. Such a chemisorption bond bringing the organic molecule to a quasi-planar position is well supported by the major changes in the XPS spectra of the electrochemically biased samples with respect to the as-prepared ones. Two distinct N 1s species instead of one and a shift of 1.6 eV to higher BE of the terthiophene S 2s core level are strong evidence for a potential-induced change in the adsorption geometry. Taking into account that the acceptor-like surface state group located close to the semiconductor valence edge (EC,S=-1.06 eV) may correspond to the LUMO level (shifted downward by the adsorption process), we assume that the organic molecule, initially adsorbed by the thiolate end, undergoes a conformational change from a tilted to an almost flat position when the applied potential brings the semiconductor Fermi level into its neighborhood. This assumption is in a very good agreement with the potential-induced variation in the thiol thickness estimated from the thiol capacitance.

5.
Vet Hum Toxicol ; 26(4): 305-8, 1984 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6464348

RESUMO

Groups of rats were given either propoxur, were left as untreated controls, or were given phenobarbital, DDT, chlordane or toxaphene which are known to induce liver microsomal detoxification enzymes. Microsomal enzyme activity was measured by testing the ability of liver homogenates to degrade EPN (O-ethyl O-(4-nitrophenyl) phenylphosphonothioate) to p-nitrophenol. The activity of aminopyrine-N-demethylase, cytochrome P-450 and p-nitroanisole-O-demethylase in liver homogenates of rats receiving propoxur was measured. Liver microsomal detoxification enzymes were not induced by propoxur exposure.


Assuntos
Microssomos Hepáticos/enzimologia , Propoxur/toxicidade , Aminopirina N-Desmetilase/metabolismo , Animais , Sistema Enzimático do Citocromo P-450/metabolismo , Indução Enzimática , Feminino , Masculino , Nitroanisol O-Desmetilase/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Fenobarbital/farmacologia , Ácido Fenilfosfonotioico, 2-Etil 2-(4-Nitrofenil) Éster/metabolismo , Ratos , Ratos Endogâmicos
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