X-ray photon correlation spectroscopy using a fast pixel array detector with a grid mask resolution enhancer.

The performance of a fast pixel array detector with a grid mask resolution enhancer has been demonstrated for X-ray photon correlation spectroscopy (XPCS) measurements to investigate fast dynamics on a microscopic scale. A detecting system, in which each pixel of a single-photon-counting pixel array detector, PILATUS, is covered by grid mask apertures, was constructed for XPCS measurements of silica nanoparticles in polymer melts. The experimental results are confirmed to be consistent by comparison with other independent experiments. By applying this method, XPCS measurements can be carried out by customizing the hole size of the grid mask to suit the experimental conditions, such as beam size, detector size and sample-to-detector distance.

Tumor environment changed by combretastatin derivative (Cderiv) pretreatment that leads to effective tumor targeting, MRI studies, and antitumor activity of polymeric micelle carrier systems.

PURPOSE: To evaluate effect of a vascular disrupting agent, a combretastatin derivative (Cderiv), on tumor targeting for polymeric micelle carrier systems, containing either a diagnostic MRI contrast agent or a therapeutic anticancer drug. METHODS: Cderiv was pre-administered 72 h before polymeric micelle MRI contrast agent injection. Accumulation of the MRI contrast agent in colon 26 murine tumor was evaluated with or without pretreatment of Cderiv by ICP and MRI. RESULTS: Significantly higher accumulation of the MRI contrast agent was found in tumor tissues when Cderiv was administered at 72 h before MRI contrast agent injection. T(1)-weighted images of the tumor exhibited substantial signal enhancement in tumor area at 24 h after the contrast agent injection. In T(1)-weighted images, remarkable T(1)-signal enhancements were observed in part of tumor, not in whole tumor. These results indicate that Cderiv pretreatment considerably enhanced the permeability of the tumor blood vessels. Antitumor activity of adriamycin encapsulated polymeric micelles with the Cderiv pretreatment suppressed tumor growth in 44As3 human gastric scirrhous carcinoma-bearing nude mice. CONCLUSIONS: Pretreatment of Cderiv enhanced tumor permeability, resulting in higher accumulation of polymeric micelle carrier systems in solid tumors.

Effects of organic solvents on drug incorporation into polymeric carriers and morphological analyses of drug-incorporated polymeric micelles.

We incorporated an anticancer agent, camptothecin (CPT), into polymeric micelle carriers by using two different solvents (TFE and chloroform) in the solvent-evaporation drug incorporation process. We observed significant differences in the drug-incorporation behaviors, in the morphologies of the incorporated drug and the polymeric micelles, and in the pharmacokinetic behaviors between the two solvents' cases. In particular, the CPT-incorporated polymeric micelles prepared with TFE as the incorporation solvent exhibited more stable circulation in blood than those prepared with chloroform. This contrast indicates a novel technological perspective regarding the drug incorporation into polymeric micelle carriers. Morphological analyses of the inner core have revealed the presence of the directed alignment of the CPT molecules and CPT crystals in the micelle inner core. This is the first report of the morphologies of the drug incorporated into the polymeric micelle inner cores. We believe these analyses are very important for further pharmaceutical developments of polymeric micelle drug-carrier systems.

Impact of dry ejaculation caused by highly selective alpha1A-blocker: randomized, double-blind, placebo-controlled crossover pilot study in healthy volunteer men.

INTRODUCTION: Dry ejaculation with loss of seminal emission is reported in patients who have been administered silodosin, an alpha1A-adrenoceptor antagonist. AIM: We investigated the impact of dry ejaculation caused by orally administered silodosin on orgasmic function. METHODS: In a double-blind crossover study, 50 healthy volunteer men were randomly assigned to receive either a single dose of 4-mg silodosin or placebo with 3 days of washout before crossover. Subjects masturbated 4 hours after administering agents. MAIN OUTCOME MEASURES: Numerical rating scale (NRS) score from 0 (highest) to 10 (lowest) for subjective quality of orgasm, the subjective number of contractions of the bulbocavernosus/pelvic floor muscles, and the amount of semen were examined. Results. After the administration of silodosin, the NRS score worsened by 1.3 points (P = 0.003), the number of contractions of the bulbocavernosus/pelvic floor muscles decreased by about 1 (P = 0.003), and there was a decrease of 1.8 mL in the amount of semen produced (P < 0.0001). Eleven men overall (22%) on silodosin administration had less than a 50% decrease from baseline in the amount of semen. CONCLUSIONS: Silodosin may adversely affect the subjective orgasmic function by causing an abnormal ejaculation with decreased (or no) semen discharge and a decrease in the number of bulbocavernosus/pelvic floor muscle contractions. Semen passing through the urethra and sufficient rhythmic contraction of the muscle of the pelvic floor may contribute to the subjective pleasure of orgasm.

Growth kinetics and morphology of self-assembled monolayers formed by contact printing 7-octenyltrichlorosilane and octadecyltrichlorosilane on Si(100) wafers.

The growth kinetics and morphologies of self-assembled monolayers deposited by contact printing 7-octenyltrichlorosilane (OCT) and octadecyltrichlorosilane (OTS) on Si(100) were studied by ellipsometry and atomic force microscopy. We found that, for both OCT and OTS, full monolayers could be obtained at room temperature after printing times of 120-180 s; the printing-based monolayer assembly processes follow apparent Langmuir adsorption kinetics, with the measured film growth rates increasing both with the ambient humidity and with concentration of the ink used to load the stamp. At a dew point of 10 degrees C and an ink concentration (in toluene) of 50 mM, the observed film growth rate constant is 0.05 s(-)(1). When the printing was carried out at a lower ambient humidity (dew points of 1-3 degrees C), the measured rates of assembly were approximately a factor of 2 slower. Increasing the deposition temperature from 25 to 45 degrees C under these conditions increased the film growth rate only slightly. The morphology of the films depends on the identity of the ink. Uniform, high-coverage films could be obtained readily from the eight-carbon chain length adsorbate OCT, provided that the stamp was not overloaded with the ink; for high concentrations outside of the optimal range, the surface presented significant numbers of adsorbed particles ascribed, in part, to siloxane polymers formed by hydrolysis of the ink on the stamp before printing. In marked contrast, for the 18-carbon adsorbate OTS, the printed films always consisted of a mixture of a uniform monolayer plus adsorbed polysiloxane particles. The different film morphologies seen for OCT and OTS are proposed to result from the different transfer efficiencies of the organotrichlorosilane relative to polysiloxane hydrolysis products formed during the printing process. These transfer efficiencies exhibit sensitivities related to the permeation of the poly(dimethylsiloxane) (PDMS) stamp by the silane reagents. Short-chain inks such as OCT evidently permeate the PDMS stamp more deeply than longer-chain inks such as OTS. This difference, and the different diffusion rates of ink vs oligomeric silane hydrolysis products, determines the film morphology obtained by contact printing. The mass transfer dynamics of the process thus yield surface layers derived from varying quantities of siloxane oligomers, which subsequently transfer to the substrate along with unhydrolyzed silane adsorbate during the printing step. The structural evolution of the contact-printed films so obtained is strikingly different from that of SAMs prepared by immersion.