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1.
Parkinsonism Relat Disord ; 16(1): 16-20, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19616987

RESUMO

OBJECTIVE: 6002-US-051 was a 12-week, double-blind study evaluating the safety and efficacy of istradefylline, a selective A(2A) adenosine receptor antagonist, as monotherapy in patients with Parkinson's disease (PD). METHODS: Patients with Hoehn-Yahr stages 1-2.5 who had not received dopaminergic drugs in the past 30 days or levodopa for >30 days at anytime were randomized to 40 mg/day istradefylline or placebo. The primary efficacy outcome was the change from Baseline to Endpoint in the Unified Parkinson's Disease Rating Scale (UPDRS) Subscale III score. Safety was assessed by physical examination, laboratory tests, electrocardiograms, and adverse event monitoring. RESULTS: 176 patients comprised the intent-to-treat population. Although istradefylline showed numerically greater improvements in UPDRS Subscale III at each time point and reached statistical significance at Week 2 (LS mean difference = -1.47), it did not show statistically significant improvement from placebo for the primary endpoint (least square [LS] mean difference = -1.11). Similar proportions of patients in each group experienced treatment-emergent adverse events (63% istradefylline, 65% placebo). CONCLUSIONS: Istradefylline, as monotherapy in patients with PD, is safe and well tolerated. However, efficacy in improving motor symptoms in early PD was not statistically demonstrated by this study.


Assuntos
Antiparkinsonianos/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Purinas/uso terapêutico , Idoso , Análise de Variância , Transtornos Cognitivos/tratamento farmacológico , Transtornos Cognitivos/etiologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Doença de Parkinson/complicações , Estudos Retrospectivos , Índice de Gravidade de Doença , Estados Unidos
2.
Parkinsonism Relat Disord ; 14(3): 205-12, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17900967

RESUMO

OBJECTIVE: This multicenter, cross-sectional study was conducted to determine the sensitivity and specificity of a 9-item Wearing-off Questionnaire (WOQ-9) compared with assessment by a clinician. METHODS: Patients with a diagnosis of Parkinson's disease (PD) for 5 or=90 days, completed the WOQ-9 before independent evaluation by the physician. RESULTS: One hundred fifty-seven patients reported WO using the WOQ-9; only 79 had been previously diagnosed with WO by a physician. The most frequent items used by physicians to diagnose WO included type of symptoms (69.6%), symptom response (63.3%), and timing of symptom response (58.2%) to medication. Physician assessment of WO and WOQ-9 results corresponded in 76 of 79 cases; physicians disagreed with WO identification in 81 of 157 cases. Sensitivity of the WOQ-9 was 96.2% and specificity was 40.9%. CONCLUSION: The WOQ-9 is a useful screening tool to aid diagnosis of WO in PD patients.


Assuntos
Avaliação da Deficiência , Resistência a Medicamentos/fisiologia , Avaliação de Resultados em Cuidados de Saúde , Doença de Parkinson/fisiopatologia , Inquéritos e Questionários , Idoso , Antiparkinsonianos/uso terapêutico , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/tratamento farmacológico , Estudos Retrospectivos , Sensibilidade e Especificidade , Índice de Gravidade de Doença
3.
Chest ; 110(2): 577-8, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8697877
4.
Am Surg ; 61(11): 954-5, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7486424

RESUMO

Most lipomas occurring in the scrotum originate and develop in the spermatic cord. In rare cases, however, lipomas originate in the fat cells of the subcutaneous tissues of the scrotal walls themselves. These primary lipomas of the scrotum vary in size. We describe a patient with a scrotal mass that, to our knowledge, is the largest scrotal lipoma originating in the tunica dartos reported in the English literature.


Assuntos
Neoplasias dos Genitais Masculinos/patologia , Lipoma/patologia , Escroto/patologia , Adulto , Neoplasias dos Genitais Masculinos/epidemiologia , Neoplasias dos Genitais Masculinos/cirurgia , Humanos , Lipoma/epidemiologia , Lipoma/cirurgia , Masculino
5.
Nat Struct Biol ; 1(11): 771-81, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7634087

RESUMO

In vertebrate rod cells, the activated alpha-subunit of rod transducin interacts with the gamma (regulatory) subunits of phosphodiesterase to disinhibit the catalytic subunits. A 22-amino acid long region of rod transducin involved in phosphodiesterase activation has recently been identified. We have used peptides from this region of rod transducin and from several other G protein alpha-subunits to study the nature and specificity of the G protein alpha-effector interaction. Although peptides derived from rod transducin, cone transducin and gustducin are similar, only the rod peptide is capable of activating rod phosphodiesterase. Using substituted peptides we have identified five residues on one exposed face of rod transducin as important to phosphodiesterase activation. These results disagree with previous models which propose that loop regions of rod transducin interact with phosphodiesterase gamma.


Assuntos
3',5'-AMP Cíclico Fosfodiesterases/metabolismo , Transducina/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Bovinos , Ativação Enzimática , Proteínas de Ligação ao GTP/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Ratos , Células Fotorreceptoras Retinianas Bastonetes/enzimologia , Homologia de Sequência de Aminoácidos
6.
Biopolymers ; 32(6): 649-66, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1643268

RESUMO

Solution structures were determined for a linear analogue of growth hormone releasing factor (GRF), and cyclic and dicyclic analogues in which the side chains of aspartyl and lysyl residues spaced at positions i-(i + 4) were joined to form a lactam. The four analogues were [Ala15]-GRF-(1-29)-NH2 and its cyclo8-12, cyclo21-25, and dicyclo8-12;21-25 derivatives. The peptides were studied in two solvent systems: 75% methanol/25% water at pH 6.0; and 100% water at pH 3.0. CD spectroscopy was used to assess the overall alpha-helical content. Nuclear magnetic resonance spectroscopy was used to determine the structures in more detail. Nearly complete proton resonance assignments were made for each of the peptides, in both solvents. Nuclear Overhauser effects were converted into distance constraints and applied in the molecular dynamics program CHARMM to evaluate the range of low-energy structures that satisfied the nmr data. In 75% methanol, all of the peptides are comprised of a single alpha-helical segment with fraying of one to three residues at each end. The linear analogue has a tendency to kink. In water, the analogues have two helical segments with flexible regions between them and at the termini of the peptides. The linear analogue is helical at residues 7-14 and 21-28. In the cyclo8-12 analogue, the N-terminal helical region extends to include residues 7-19, while the other helical region is slightly shortened. In the cyclo21-25 analogue, the C-terminal helical region is extended to include residues 19-28, while the N-terminal helical region is destabilized. The dicyclic analogue has the largest N-terminal helix, spanning residues 7-20, but its helical segment at residues 21-28 is not well ordered. All of the analogues exhibit substantial biological activity. The cyclic and dicyclic analogues show dramatically increased resistance to degradation during incubation with human plasma. The i-(i + 4) lactam, therefore, appears to be a synthetic means of stabilizing a local alpha-helical conformation, which may be of general use in the design of active, stable peptides.


Assuntos
Hormônio Liberador de Hormônio do Crescimento/análogos & derivados , Hormônio Liberador de Hormônio do Crescimento/química , Peptídeos Cíclicos/química , Sequência de Aminoácidos , Dicroísmo Circular , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Software , Soluções
7.
Addict Behav ; 17(3): 291-6, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1636476

RESUMO

Until now mass media smoking cessation studies have relied almost exclusively on self-reports of smoking cessation because biochemical confirmation has not seemed practical. This study investigated the reliability of mailed salivary cotinine specimens for the determination of smoking status. Two simultaneous saliva specimens were obtained from 10 smokers and 10 nonsmokers. One of each pair was frozen immediately. The other was sent through the local U.S. mail and then subjected to additional physical agitation and heat before being frozen. All specimens were subsequently analyzed for cotinine. No cotinine was detectable in any of the nonsmokers' specimens. There was excellent correlation between the paired smokers' specimens. These results show that the mailing of saliva specimens for cotinine analysis is practical and provides accurate data on smoking status. It is an approach which could easily be used in mass media smoking cessation studies to biochemically confirm smoking behavior.


Assuntos
Cotinina/farmacocinética , Saliva/metabolismo , Fumar/sangue , Manejo de Espécimes , Humanos , Serviços Postais , Valor Preditivo dos Testes
8.
Biochemistry ; 28(6): 2399-409, 1989 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-2730873

RESUMO

Structures have been determined for a potent analogue of vasoactive intestinal peptide (VIP), Ac-[Lys12, Lys14, Nle17, Val26, Thr28]VIP (VIP'), in methanol/water solutions. In CD studies, both VIP and VIP' were helical in methanol/water, with the percentage of alpha-helix increasing with percentage methanol. The pH had little effect on the structure. Complete 1H NMR assignments were made for VIP' in 25% methanol at pH 4 and 6 and in 50% methanol at pH 6, using two-dimensional COSY, NOESY, and relay-COSY experiments. There were no widespread changes in chemical shifts between the samples at pH 4 and 6; however, widespread changes were observed between the samples in 25% and 50% methanol. Complete sets of NOEs were obtained for VIP' in 25% methanol, pH 4, and in 50% methanol, pH 6. These NOEs were converted into distance constraints and applied in molecular dynamics and energy minimization calculations using the program CHARMM. A set of low-energy structures was obtained for VIP' in each solvent system. In 25% methanol, VIP' has two helical segments at residues 9-17 and 23-28. The remainder of the structure is not well determined. In 50% methanol, residues 8-26 form a regular, well-defined alpha-helix and residues 5-8 form a type III beta-turn. The remaining residues are not ordered. These structural assessments agree with the CD data. In the lowest energy structure in 50% methanol, the side chains of Asp3, Phe6, Thr7, and Tyr10 are clustered together--these residues are conserved throughout the family of peptide hormones homologous to VIP.


Assuntos
Peptídeo Intestinal Vasoativo/análogos & derivados , Dicroísmo Circular , Espectroscopia de Ressonância Magnética/métodos , Modelos Moleculares , Conformação Proteica , Termodinâmica
10.
J Lipid Res ; 25(6): 646-50, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6747468

RESUMO

This paper describes the synthesis of 5 beta-cholestane-3 beta, 7 alpha,25-triol and 5 beta-cholestane-3 beta, 7 alpha, 12 alpha, 25-tetrol from their corresponding 3 alpha-analogs. The method consists of refluxing a mixture of a steroid alcohol, triphenylphosphine, and diethyl azodicarboxylate in benzene solution with an acid such as formic acid. The sterically pure ester (3 beta-formate) so formed after saponification then allows an easy access to the epimer of the starting alcohol. Differentiation of these 3 beta-hydroxy bile alcohols from their corresponding 3 alpha-epimeric analogs was made possible on the basis of proton, 13C-NMR, and mass spectra as well as chromatographic mobility. Steric requirements of sterols and nucleophilicity of attacking acidic components played an important role for the success of this synthesis. Only equatorial hydroxyl groups in these bile alcohols reacted under mild conditions and epimerization, as well as protection of the alcoholic group, was achieved in one step. Formic acid was the acid of choice since the axial formate ester formed is sufficiently reactive to be hydrolyzed (KHCO3/aq X MeOH) under mild conditions.


Assuntos
Ácidos e Sais Biliares , Colestanóis/síntese química , Espectroscopia de Ressonância Magnética , Estereoisomerismo
11.
Steroids ; 42(4): 441-8, 1983 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6679948

RESUMO

An unrecognized pentahydroxy bile alcohol has been isolated from the bile and feces of patients with cerebrotendinous xanthomatosis (CTX). Its structure, 5 beta-cholestane-3 alpha, 7 alpha, 12 alpha, 25, 26-pentol has been deduced by spectroscopic methods and confirmed by comparison with a synthetic analog.


Assuntos
Bile/metabolismo , Encefalopatias/metabolismo , Colestanóis/análise , Xantomatose/metabolismo , Cromatografia Gasosa , Cromatografia em Camada Fina , Fezes/análise , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Oxirredução , Esteróis/análise
12.
J Lipid Res ; 21(1): 130-5, 1980 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7354249

RESUMO

This study was designed to examine whether 13C nuclear magnetic resonance (NMR) spectroscopy can be used to differentiate between the 25R and 25S diastereoisomers of 5 beta-cholestane-3 alpha, 7 alpha, 26-triol, a key intermiediate in the biosynthetic pathway of chenodeoxycholic acid. Chemical shift values were assigned to the individual carbon atoms with the help of model compounds and multiplicity in the single-frequency off-resonance decoupled spectra. It was found that the corresponding carbons 1-20 afforded identical chemical shifts for both compounds, whereas five of the remaining side-chain carbons gave observed shift differences of 0.05-0.20 ppm. Thus 13C NMR can be used as an additional tool to distinguish between the two 5 beta-cholestanetriols isomeric at C-25.


Assuntos
Colestanóis , Fenômenos Químicos , Química , Espectroscopia de Ressonância Magnética , Estereoisomerismo
13.
J Microsc ; 114(1): 31-9, 1978 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-361962

RESUMO

In morphometric studies of lung tissue, accurate determination of the total number of any specific type of cell, such as the endothelial cell, requires knowledge of the shape of the cell nucleus. This knowledge of shape is necessary to calculate the mean caliper diameter, which, in turn, is an indispensible element of the equation for the number of nuclei (therefore cells) per unit volume (NV). Nine human hung endothelial cell nuclei were therfore reconstructed in dental wax from serial sections and were found to be pleomorphic triaxial ellipsoids. Five of these approached an oblate shape. The axes of these nine nuclear models were directly measured and a computer program using numerical integration was written to determine the mean caliper diameters of these ellipsoids. The estimated mean semi-axes of the nine nuclei were (+/-SD) 5.98+/-1.61, 3.61+/-0.70, 1.36+/-0.34; and the estimated overall mean caliper diameter for the total population of human lung endothelial nuclei was 7.97+/-1.27 micrometers.


Assuntos
Núcleo Celular/ultraestrutura , Pulmão/ultraestrutura , Modelos Estruturais , Endotélio/ultraestrutura , Técnicas Histológicas , Humanos , Moldagem de Cera para Incrustações
14.
J Microsc ; 114(1): 41-8, 1978 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-361963

RESUMO

Morphometric studies of lung tissue in which the number of cell nuclei (therefore cells) are determined require the determination of the mean caliper diameter for each type of cell nucleus studied. We determined the mean caliper diameter for the five most common classes of cells found in the gas exchange portion of rat lung. This was done by serially sectioning through ten nuclei from each class of cells and then constructing wax models of the nuclei. Most of the nuclei were found to be triaxial ellipsoids and direct measurements taken from the models were used to calculate the following estimated overall mean caliper diameters (+/-SE): alveolar type I nuclei, 7.97+/-0.2 micrometers, alveolar type II nuceli, 6.77 +/-0.19 micrometers, interstitial cell nuclei, 7.64+/-0.35 micrometers, endothelial cell nuclei, 7.22+/-0.19 micrometers, and alveolar macrophage nuclei, 7.65+/-0.17 micrometers.


Assuntos
Núcleo Celular/ultraestrutura , Pulmão/ultraestrutura , Modelos Estruturais , Ratos/anatomia & histologia , Animais , Técnicas Histológicas , Moldagem de Cera para Incrustações , Pulmão/citologia , Masculino
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