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1.
J Sex Res ; 59(9): 1133-1139, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35060403

RESUMO

We tested whether CSD500 (Futura Medical; Guildford, UK), a novel condom containing erectogenic gel designed to increase penile firmness, penile size, and erection duration, results in greater sexual pleasure. In 2017-2020, we randomized heterosexual couples in Thanh Hoa, Vietnam to use CSD500 (N = 248) or standard condoms (N = 252) and followed them up for six months. Women completed the Quality of Sexual Experience (QSE) scale; men completed the QSE, Sexual Experience Questionnaire (SEX-Q), and 11 condom acceptability items. Female participants' mean age was 32.1 years (SD = 0.24; range 21-46). QSE scores were higher among women (B, 0.12; 95% CI, 0.03-0.21) and men (B, 0.21; 95% CI, 0.08-0.35) in the CSD500 relative to the control arm. SEX-Q scores were higher among men in the CSD500 compared to the control arm (B, 3.22; 95% CI, 1.53-4.91). Higher proportions of men in the CSD500 relative to the control arm reported the condom felt "natural" during sex (68.6% vs. 32.3%; p < .01) and that sex with the condom felt "a lot better" than condomless sex (15.5% vs. 5.3%; p < .01). Compared with standard condoms, CSD500 use was associated with higher reports of sexual pleasure and condom acceptability.


Assuntos
Preservativos , Parceiros Sexuais , Masculino , Feminino , Humanos , Adulto , Prazer , Comportamento Sexual , Heterossexualidade
3.
Protein Sci ; 10(3): 581-91, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11344326

RESUMO

Two new parameters, I: and C:, are introduced for the quantitative evaluation of functional chimeras: I: (impact) and C: (context dependence) are the free energy difference and sum, respectively, of the effects on a given property measured in forward and retro chimeras. The forward chimera is made by substitution of a part "a" from ensemble A into the analogous position of homologous ensemble B (S:(B --> A)). The C: value is a measure of the interaction of the interrogated position with its surroundings, whereas I: is an expression of the quantitative importance of the probed position. Both I: and C: vary with the evaluated property, for example, kinetics, binding, thermostability, and so forth. The retro chimera is the reverse substitution of the analogous part "b" from B into A, S:(A --> B). The I: and C: values derived from original data for forward and retro mutations in aspartate and tyrosine aminotransferase, from literature data for quasi domain exchange in oncomodulin and for the interaction of Tat with bovine and human TAR are evaluated. The most salient derived conclusions are, first, that Thr 109 (AATase) or Ser 109 (TATase) is an important discriminator for dicarboxylic acid selectivity by these two enzymes (I: < -2.9 kcal/mol). The T109S mutation in AATase produces a nearly equal and opposite effect to S109T in TATase (C: < 0.4 kcal/mol). Second, an I: value of 5.5 kcal/mol describes the effects of mirror mutations D94S (site 1) and S55D (site 2) in the Ca(2+) binding sites of oncomodulin on Ca(2+) affinity. The second mirror set, G98D (site 1) and D59G (site 2), yields a smaller impact (I: = -3.4 kcal/mol) on Ca(2+) binding; however, the effect is significantly more nearly context independent (C: = -0.6 versus C: = -2.7 kcal/mol). Third, the stem and loop regions of HIV and BIV TAR are predominantly responsible for the species specific interaction with BIV Tat(65-81) (I: = -1.5 to -1.6 kcal/mol), whereas I: = 0.1 kcal/mol for bulge TAR chimeras. The C: values are from -0.3 to -1.2 kcal/mol. The analysis described should have important applications to protein design.


Assuntos
Aspartato Aminotransferases/genética , Mutagênese Sítio-Dirigida/genética , Relação Quantitativa Estrutura-Atividade , Proteínas Recombinantes de Fusão/genética , Tirosina Transaminase/genética , Aspartato Aminotransferases/química , Aspartato Aminotransferases/metabolismo , Proteínas de Ligação ao Cálcio/química , Escherichia coli , Cinética , Substâncias Macromoleculares , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Ativação Transcricional , Tirosina Transaminase/química , Tirosina Transaminase/metabolismo
4.
Anal Biochem ; 253(1): 46-9, 1997 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-9356140

RESUMO

A continuous assay for Escherichia coli tyrosine aminotransferase (TATase) that employs Lactobacillus delbrueckii ssp. bulgaricus hydroxyisocaproate dehydrogenase (HO-HxoDH) as a coupling enzyme is described. alpha-Keto acids, including those formed by TATase-catalyzed transamination of l-phenylalanine, l-tyrosine, l-tryptophan, l-methionine, and l-leucine, are converted to the corresponding alpha-hydroxy acids by the auxiliary enzyme. The concomitant reduction of NADH by this enzyme can be followed as a decrease in absorbance at 340 nm. Importantly, HO-HxoDHcatalyzed reduction of alpha-ketoglutarate (alpha-KG), a cosubstrate of TATase required to regenerate the pyridoxal-5'-phosphate cofactor of this enzyme from pyridoxamine-5'-phosphate, is a poor substrate and does not interfere with the assay. The kinetic parameters determined for the transamination of phenylalanine by TATase (kcat = 180 s-1, KM (L-Phe) = 0.56 mM, KM (alpha-KG) = 5 mM) with HO-HxoDH as a coupling enzyme are comparable to those reported in the literature, which were determined by direct monitoring of the formation of phenylpyruvate at 280 nm. This new assay offers the advantages of increased sensitivity and broad substrate specificity.


Assuntos
Escherichia coli/enzimologia , Tirosina Transaminase/análise , Oxirredutases do Álcool , Aminoácidos/metabolismo , Indicadores e Reagentes , Cinética , Lactobacillus/enzimologia , Espectrofotometria Ultravioleta/métodos , Especificidade por Substrato , Tirosina Transaminase/metabolismo
5.
Angiology ; 38(10): 727-36, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2959174

RESUMO

The cutaneous laser Doppler device (LDF) was employed to determine its usefulness in differentiating the circulation of the feet in normal subjects from that in patients with arteriosclerosis obliterans. It is shown that the laser Doppler frequencies correlated well with results from venous occlusion plethysmography, which measured volume rate of flow. Thus, one can determine volume rate of flow by the simple Doppler method. There was a linear relationship between these two methods of measurements. Using the LDF method, it was determined that normal individuals have toe flows that on the average are 42% of finger flows in supine resting subjects. In peripheral vascular disease of the lower extremities, the LDF measurements showed a decreased circulation in the large toes when the patients are supine and the lower extremities flat. The results between health and disease are exaggerated by elevating the feet, at which time the diseased circulation falls to extremely low values compared with those of normal subjects. A similar decrease in skin oxygen tension in the diseased lower extremities was observed when the limbs were elevated.


Assuntos
Lasers , Reologia , Pele/irrigação sanguínea , Adulto , Arteriosclerose Obliterante/fisiopatologia , Velocidade do Fluxo Sanguíneo , Monitorização Transcutânea dos Gases Sanguíneos , Feminino , Dedos/irrigação sanguínea , Humanos , Claudicação Intermitente/fisiopatologia , Masculino , Pessoa de Meia-Idade , Oxigênio/metabolismo , Pletismografia , Pele/metabolismo , Supinação , Dedos do Pé/irrigação sanguínea
6.
J Pharmacol ; 12(3): 263-75, 1981.
Artigo em Francês | MEDLINE | ID: mdl-7289623

RESUMO

This study investigates in anaesthetized dogs kinetics and efficiency of peripheral vasodilator effects of naftidrofuryl and nicergoline after intraarterial and intramuscular administration and also their possible action on arterial blood pressure. The study of kinetics of vasodilator effects of naftidrofuryl and nicergoline by the intraarterial route at doses equal or according to the doses used in clinical practice on the one hand and the study of the dose-vasodilatation and dose-hypotension regressions for doses of 0.025-0.050-0.100 mg/kg on the other hand show that: 1. naftidrofuryl has a good dilator effect, stronger and a little shorter than that of nicergoline. 2. nicergoline produces a dose-related decrease in arterial pressure whereas naftidrofuryl does not alter it. The results obtained by the intramuscular administration show that: 3. naftidrofuryl, at 2-4-8 mg/kg, has a strong and lasting vasodilator effect, proportional to doses, without alteration of the arterial pressure. 4. nicergoline, at 0.25-1-4 mg/kg, is very hypotensive and its vasodilator effect observed by the intraarterial route is not confirmed.


Assuntos
Ergolinas/farmacologia , Furanos/farmacologia , Nafronil/farmacologia , Nicergolina/farmacologia , Vasodilatadores , Animais , Pressão Sanguínea , Cães , Relação Dose-Resposta a Droga , Feminino , Artéria Femoral/efeitos dos fármacos , Injeções Intra-Arteriais , Injeções Intramusculares , Cinética , Masculino , Fatores de Tempo
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