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1.
Opt Express ; 24(23): 26998, 2016 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-27857426

RESUMO

This publisher's note amends the Funding section of a recent publication [Opt. Express24, 20685 (2016].

2.
Opt Express ; 24(18): 20685-95, 2016 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-27607672

RESUMO

Synthetic two-dimensional transition metal dichalcogenides such as, tungsten disulphide (WS2), tungsten diselenide (WSe2), molybdenum disulphide (MoS2) as well as mixed molybdenum tungsten disulphide (Mo0.5W0.5S2) single crystals were grown by the chemical vapor transport method using halogens (bromine or chlorine) as transport agents. Multi- layer samples were cleaved from the single crystals, and their nonlinear optical (NLO) properties were obtained from both open aperture and closed aperture Z-scan measurements using a picosecond mode-locked Nd: YAG laser operating at a wavelength of 1064 nm, with pulse duration of 25 ps, and 20 Hz repetition rate. Both WS2 and MoS2 exhibited nonlinear saturable absorption (SA), whereas WSe2 and Mo0.5W0.5S2 showed nonlinear two-photon absorption (2PA). A large 2PA coefficient ß as high as + 1.91x10-8 cm/W was obtained for the Mo0.5W0.5S2, and an index of refraction coefficient γ = -2.47x10-9 cm2/W was obtained for the WSe2 sample.

3.
Opt Lett ; 38(5): 600-2, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23455236

RESUMO

We report a method for amplifying higher-order guided modes, synthesized with a spatial light modulator, in a hydrogen-filled hollow-core photonic crystal fiber. The gain mechanism is intermodal stimulated Raman scattering, a pump laser source in the fundamental mode providing amplification for weak higher-order seed modes at the Stokes frequency. The gain for higher-order modes up to LP31 is calculated and verified experimentally.

4.
Opt Lett ; 37(21): 4362-4, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23114296

RESUMO

In a relatively simple setup consisting of a microchip laser as pump source and two hydrogen-filled hollow-core photonic crystal fibers, a broad, phase-locked, purely rotational frequency comb is generated. This is achieved by producing a clean first Stokes seed pulse in a narrowband guiding photonic bandgap fiber via stimulated Raman scattering and then driving the same Raman transition resonantly with a pump and Stokes fields in a second broadband guiding kagomé-style fiber. Using a spectral interferometric technique based on sum frequency generation, we show that the comb components are phase locked.

5.
Oncogene ; 4(2): 249-52, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2927946

RESUMO

The plasma membrane associated subclass of simian virus 40 large T antigen is specifically acylated with palmitic acid in vivo. To further analyze possible biological functions of fatty acid acylation, we developed a target-bound cell free in vitro acylation assay, in which immunopurified large T, bound to protein A-sepharose, was incubated with [3H]fatty acid. In this assay, large T was efficiently labeled with [3H]palmitic acid, but not with [3H]myristic acid. Thus the specificity of the in vivo labeling was preserved in vitro, too. The specific acylation of large T in vitro seemed to occur by an autocatalytic reaction, since it was found to be independent of added acyltransferases and exogenous energy. The energy for this reaction must be provided by the large T molecule itself, probably by an energy-rich internal ester bond. Our results provide evidence for a novel mechanism for the covalent attachment of fatty acids to proteins, which might also operate in vivo.


Assuntos
Antígenos Transformantes de Poliomavirus/metabolismo , Ácidos Graxos/metabolismo , Acilação , Ácido Palmítico , Ácidos Palmíticos/metabolismo
6.
J Clin Endocrinol Metab ; 41(2): 395-8, 1975 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-808556

RESUMO

Total serum thyroxine (T4), free thyroxine index (FTI), thyroxine binding globulin (TBG) binding capacity, serum albumin, alpha-globulins and urinary protein excretion were measured in 50 patients with chronic renal failure, but without nephrotic syndrome. 25 patients were undergoing chronic hemodialysis. T4 was within the normal range in most patients. There was a tendency to lower T4 values as compared to an age and sex-matched control group, but this did not reach statistical significance. TBG was normal in most patients. 4 patients showed elevated TBG concomitant with elevation of other alpha-globulins. Serum albumin was significantly decreased. No correlation existed between daily protein excretion and TBG or alpha-globulins, but the correlation between serum albumin and proteinuria was highly significant. T4 and proteinuria correlated with borderline significance. A highly significant correlation between T4 and TBG-albumin values was found. No correlation existed between FTI and TBG-albumin levels. The data suggest that T4 and TBG are normal in most patients with renal failure, even in the presence of significant proteinuria. Low T4 values, when found in renal insufficiency, may be secondary to low serum albumin and possibly prealbumin.


Assuntos
Falência Renal Crônica/sangue , Proteínas de Ligação a Tiroxina/metabolismo , Tiroxina/sangue , Adulto , Idoso , Dieta , Feminino , Humanos , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Nefrose/sangue , Proteinúria , Diálise Renal , Albumina Sérica/metabolismo , Soroglobulinas/metabolismo , Fatores de Tempo
7.
J Clin Endocrinol Metab ; 42(1): 60-3, 1976 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-175085

RESUMO

The corticotropic action of a synthetic ACTH derivative, D-Ser1 Lys17,18-1-18ACTH, after intranasal insufflation of 1 mg of the peptide was evaluated in 14 normal volunteers. Plasma cortisol and urinary 17-ketogenic steroids and 17-ketosteroids rose significantly over control values in all subjects (P less than 0.001). Plasma cortisol remained above the normal range for comparable clock times for 18 hr, but fell below 15 mug/100 ml after 12 hr. No evidence for suppression of the hypothalamo-pituitary axis was found the day after ACTH administration, as judged by normal plasma and urinary steroid values and normal diurnal variation. Intranasal administration of long-acting ACTH derivatives may provide a simple, painless and effective way to stimulate endogenous corticosteroid secretion.


Assuntos
17-Cetosteroides/urina , Hormônio Adrenocorticotrópico/análogos & derivados , Hidrocortisona/sangue , Administração Intranasal , Adolescente , Hormônio Adrenocorticotrópico/administração & dosagem , Hormônio Adrenocorticotrópico/sangue , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
8.
J Med Chem ; 20(12): 1694-7, 1977 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-592339

RESUMO

s-Triazolo[4,3-a][1,4]benzodiazepines bearing various substituents in the 1 position were prepared by oxidative cyclization of the appropriate aldehyde hydrazones of 2-hydrazinobenzodiazepines. Diethyl azodicarboxylate and activated manganese dioxide were used as oxidizing agents. The new triazolo compounds were active in the CNS tests but none of them reached the potency of the known triazolobenzodiazepines.


Assuntos
Benzodiazepinas/síntese química , Hidrazonas , Animais , Benzodiazepinas/farmacologia , Sistema Nervoso Central/efeitos dos fármacos , Fenômenos Químicos , Química , Ciclização , Camundongos , Oxirredução , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/farmacologia
9.
J Med Chem ; 19(12): 1378-81, 1976 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1003422

RESUMO

7-Nitro-substituted benzodiazepines were reduced with stannous chloride in a buffered system to the corresponding 7-hydroxyamino derivatives. These compounds were alkylated, acylated, and converted to nitroso and azoxy derivatives. The rearrangement of a hydroxyamine to an aminophenol and its oxidation to an aminoquinone are also exemplified. The results of the pharmacological screening for CNS effects are given.


Assuntos
Benzodiazepinas/síntese química , Animais , Benzodiazepinas/metabolismo , Benzodiazepinas/farmacologia , Sistema Nervoso Central/efeitos dos fármacos , Depressão Química , Camundongos , Pentilenotetrazol/antagonistas & inibidores , Relação Estrutura-Atividade
10.
J Med Chem ; 26(11): 1596-601, 1983 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6138437

RESUMO

The 2-benzazepine 9-chloro-7-(2-chlorophenyl)-5H-pyrimido[5,4-d] [2]benzazepine (1) has been selected for development as an anxiolytic agent. In support of this program, we have confirmed by chemical synthesis the structures of three in vitro (rat liver homogenate) metabolites of 1 and confirmed the structure of the major in vivo (dog and man) metabolite of 1, compound 2. Two of the metabolites, arising from hydroxylation of the pyrimidobenzazepine ring at the 5-position (2) and N-oxide formation at the 3-position of the pyrimidobenzazepine ring (3), were found to be as active as 1 in a series of pharmacological tests. The third metabolite, formed by hydroxylation of the 7-phenyl group in the 4-position (4), was found to be inactive in the same pharmacological screens.


Assuntos
Ansiolíticos/síntese química , Benzazepinas/síntese química , Animais , Benzazepinas/farmacologia , Bioensaio , Diazepam/metabolismo , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Conformação Molecular , Atividade Motora/efeitos dos fármacos , Receptores de Superfície Celular/efeitos dos fármacos , Receptores de Superfície Celular/metabolismo , Receptores de GABA-A , Espectrofotometria Infravermelho , Relação Estrutura-Atividade
11.
J Med Chem ; 34(3): 1209-21, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2002463

RESUMO

A series of [1,2,4]triazolo[4,3-alpha][1,4]benzodiazepines bearing an ethynyl functionality at the 8-position and the isosteric thieno[3,2-f][1,2,4]triazolo[4,3-alpha][1,4]diazepines were prepared and evaluated as antagonists of platelet activating factor. The effects of substitution were explored in in vitro and in vivo test systems designed to measured PAF-antagonistic activity. Results are discussed and compared with previously published data. Many of the compounds had activity superior to WEB 2086, compound 1. In general, the thieno analogues exhibited better oral activity than the corresponding benzodiazepines. The duration of activity upon oral administration was modulated by the substitution on the acetylenic side chain. Compounds 71 and 81 were selected for further pharmacological evaluation as a result of their good oral potency and exceptionally long duration of action.


Assuntos
Azepinas/farmacologia , Benzodiazepinas/farmacologia , Fator de Ativação de Plaquetas/antagonistas & inibidores , Tiofenos/farmacologia , Triazóis/farmacologia , Animais , Azepinas/síntese química , Benzodiazepinas/síntese química , Plaquetas/metabolismo , Broncoconstrição/efeitos dos fármacos , Fenômenos Químicos , Química , Cães , Cobaias , Masculino , Conformação Molecular , Estrutura Molecular , Fator de Ativação de Plaquetas/metabolismo , Relação Estrutura-Atividade , Tiofenos/síntese química , Triazóis/síntese química
12.
J Med Chem ; 34(4): 1440-6, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2016721

RESUMO

The preparations of thienotriazolodiazepines bearing a substituted ethynyl group at the 2-position, and the corresponding cis-olefins and fully saturated analogues are described. The compounds were evaluated as potential antagonists of platelet-activating factor (PAF) in in vitro and in vitro test models. The new thienotriazolodiazepines are compared with known related compounds such as WEB 2086 (compound 6) and the phenylethyl derivatives 27 and 28.


Assuntos
Azepinas/síntese química , Fator de Ativação de Plaquetas/antagonistas & inibidores , Tiofenos/síntese química , Triazóis/síntese química , Animais , Azepinas/química , Azepinas/farmacologia , Cobaias , Indicadores e Reagentes , Pulmão/efeitos dos fármacos , Pulmão/fisiologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Relação Estrutura-Atividade , Tiofenos/química , Tiofenos/farmacologia , Triazóis/química , Triazóis/farmacologia
13.
J Med Chem ; 26(3): 367-72, 1983 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6681844

RESUMO

The facile synthesis of [1,2,3]triazolo((4,5-d][2]benzazepines and dibenzo[c,f][1,2,3]triazolo[3,4-a]azepines by the addition of sodium azide to acetylenic benzophenones is described. Examination of the pharmacological data indicates that selected triazolobenzazepines are as potent as diazepam in the anti-pentylenetetrazole test and are weaker in the inclined screen and rotarod tests, suggesting that these compounds have antianxiety properties similar to diazepam with fewer deficits in motor coordination. In addition, a possible diazepam antagonist was found in the triazolo-benzazepine series. The dibenzotriazoloazepines were found to be inactive in four standard CNS screening procedures.


Assuntos
Dibenzazepinas/síntese química , Triazóis/síntese química , Animais , Comportamento Animal/efeitos dos fármacos , Fenômenos Químicos , Química , Diazepam/metabolismo , Dibenzazepinas/farmacologia , Pentilenotetrazol/antagonistas & inibidores , Equilíbrio Postural/efeitos dos fármacos , Triazóis/farmacologia
14.
J Med Chem ; 26(11): 1589-96, 1983 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6138436

RESUMO

A series of 5H-pyrimido[5,4-d][2]benzazepines has been synthesized, starting from the corresponding 2-benzazepin-5-ones, and evaluated as potential anxiolytic agents. Selected compounds from this series show a pharmacological profile of action different than that of diazepam. They are more potent than diazepam in the anti-pentylenetetrazole test and in the [3H]diazepam binding assay, yet show less activity in the inclined screen test. A pharmacological data profile is given for 9-chloro-7-(2-chlorophenyl)-5H-pyrimido[5,4-d] [2]benzazepine (7c). The structure-activity relationships of these potential anxiolytic agents are discussed.


Assuntos
Ansiolíticos/síntese química , Benzazepinas/síntese química , Animais , Benzazepinas/farmacologia , Bioensaio , Diazepam/metabolismo , Avaliação Pré-Clínica de Medicamentos , Interações Medicamentosas , Etanol/farmacologia , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Pirimidinas/síntese química , Pirimidinas/farmacologia , Receptores de Superfície Celular/efeitos dos fármacos , Receptores de Superfície Celular/metabolismo , Receptores de GABA-A , Reflexo/efeitos dos fármacos , Espectrofotometria Infravermelho , Relação Estrutura-Atividade
15.
Urologe A ; 38(4): 370-1, 1999 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-10444797

RESUMO

A 74-years old patient is admitted to the hospital with a over a period of 4 years growing, scrotal, ulcerated tumor. There is no connection to the testicle or the epididymis palpable. All laboratory findings including the tumorparameters are normal. The scrotal sonography shows a solid tumor, that is filled with vessels in the Doppler sonography. The complete tumor resection with histological examination leads to the diagnosis of a scrotal leiomyoma. This rare, benign tumor is a differential diagnosis to paratesticular or non-germinal tumors.


Assuntos
Neoplasias dos Genitais Masculinos/diagnóstico , Leiomioma/diagnóstico , Escroto , Idoso , Diagnóstico Diferencial , Neoplasias dos Genitais Masculinos/patologia , Neoplasias dos Genitais Masculinos/cirurgia , Humanos , Leiomioma/patologia , Leiomioma/cirurgia , Masculino , Escroto/patologia , Escroto/cirurgia , Úlcera Cutânea/diagnóstico , Úlcera Cutânea/patologia , Úlcera Cutânea/cirurgia , Ultrassonografia Doppler
16.
J Fr Ophtalmol ; 36(9): 769-74, 2013 Nov.
Artigo em Francês | MEDLINE | ID: mdl-23932587

RESUMO

Untreated refractive errors represent the main visual impairment in the world but also the easiest to avoid. The goal of this survey is to use clinical and epidemiological data to efficiently plan distribution of corrective glasses in a project supported by the Swiss Red Cross in the central region of Togo. To achieve this goal, 66 primary schools were identified randomly in the catchment area of the project. The teachers at these schools were previously trained to test visual acuity (VA). The schoolchildren referred by these teachers were examined by eye care professionals. The schoolchildren with ametropia (VA≤7/10 in at least one eye) underwent cycloplegic autorefraction. Of a total of 19,252 registered schoolchildren, 13,039 underwent VA testing by the teachers (participation rate=68%). Among them, 366 cases of ametropia were identified (prevalence about 3%). The average age of the schoolchildren examined was 10.7±2.3years, with a sex ratio of 1.06. Autorefraction, which was performed for 37% of the schoolchildren with ametropia allowed them to be classified into three groups: hyperopia (4%), myopia (5%) and astigmatism of all types (91%). Regardless of the type of ametropia, the degree of severity was mild in 88%. The results of this survey have highlighted the importance of the teachers' contribution to eye care education in the struggle against refractive errors within the school environment, as well as helping to efficiently plan actions against ametropia.


Assuntos
Erros de Refração/epidemiologia , Adolescente , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino , Prevalência , Instituições Acadêmicas , Togo/epidemiologia , Testes Visuais
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