Intravascular ultrasound analysis of the radial artery for coronary artery bypass grafting.

BACKGROUND: The radial artery has become a popular conduit for coronary artery bypass surgery. However, limited information has been provided regarding the atherosclerotic nature of this artery, which may affect both the immediate intraoperative difficulties and long-term graft patency. METHODS: We examined intravascular ultrasound (IVUS) images of the radial artery in patients with coronary artery diseases. Cross sections of the radial artery were assessed using the following factors: lumen diameter, lumen area, vessel diameter, vessel area, plaque area, percent plaque area, and extent of calcium deposition. RESULTS: The IVUS images were obtained from radial arteries of 58 patients (47 men, average 67 +/- 9 years) during transradial procedures; ie, transradial coronary angiography and/or transradial coronary intervention. Mean luminal diameter was 3.28 +/- 0.69 mm and 3.00 +/- 0.70 mm at the proximal and distal segments, respectively, and 2.58 +/- 0.73 mm at the minimal lumen cross section. A percent plaque area greater than 50% was seen in five radial arteries (8.6%) whose average plaque length was 26.4 +/- 30.8 mm. Of these, one showed a plaque length greater than 50 mm, and another showed vessel caliber less than 2.0 mm. Five of 58 radial arteries (8.6%) showed calcium deposition, two of which showed diffuse calcification (> 50 mm). Thus, among 58 radial arteries, four (6.9%: one with diffuse arteriosclerosis, one small radial artery, two with diffuse calcification) were considered unsuitable for bypass conduit. CONCLUSIONS: Preoperative evaluation of the radial artery is recommended in order to prevent unnecessary exploration of the forearm and to improve graft patency.

420 nm intense continuous light therapy for acne.

BACKGROUND: Topical antibiotics, isotretinoin or systemic antibiotics are usually used for acne therapy. However, isotretinoin cannot be used during pregnancy because it can cause significant birth defects while systemic antibiotics can have adverse side effects such as gastrointestinal irritation, photosensitivity and tetracycline sensitivity. Describe here is a high-intensity, narrow-band, blue light (ClearLight) system, and its therapeutic clinical effect is investigated on acne using cutaneous measurements, bacterial observations and ultrastructural changes. MATERIALS AND METHODS: A total of 28 adult healthy volunteers with facial acne (mean age 28.1 years, range 16-56 years) were recruited for this study. They were treated with a total of eight serial biweekly 15-minute treatment sessions. Clinical counts of acne, as well as moisture, sebum and pH measurements were taken between each session. Nine of the 28 patients were followed for 2-3 months after the last treatment. Detection of bacteria in acne pustules was analyzed by culture and by polymerase chain reaction (PCR). Ultrastructural changes were examined in eight patients after four sessions of the light therapy. RESULTS: All patients completed the study. Overall, there was a 64.7% improvement in acne lesions. There were no bacterial changes before or after the therapy, although damaged Propionibacterium acnes were observed at the ultrastructural level. CONCLUSIONS: ClearLight performed eight times over 4 weeks can be useful in the treatment of acne. Further investigation will be needed to elucidate the mechanism of action of ClearLight.

Identification of R(-)-isomer of efonidipine as a selective blocker of T-type Ca2+ channels.

Efonidipine, a derivative of dihydropyridine Ca(2+) antagonist, is known to block both L- and T-type Ca(2+) channels. It remains to be clarified, however, whether efonidipine affects other voltage-dependent Ca(2+) channel subtypes such as N-, P/Q- and R-types, and whether the optical isomers of efonidipine have different selectivities in blocking these Ca(2+) channels, including L- and T-types. To address these issues, the effects of efonidipine and its R(-)- and S(+)-isomers on these Ca(2+) channel subtypes were examined electrophysiologically in the expression systems using Xenopus oocytes and baby hamster kidney cells (BHK tk-ts13). Efonidipine, a mixture of R(-)- and S(+)-isomers, exerted blocking actions on L- and T-types, but no effects on N-, P/Q- and R-type Ca(2+) channels. The selective blocking actions on L- and T-type channels were reproduced by the S(+)-efonidipine isomer. By contrast, the R(-)-efonidipine isomer preferentially blocked T-type channels. The blocking actions of efonidipine and its enantiomers were dependent on holding potentials. These findings indicate that the R(-)-isomer of efonidipine is a specific blocker of the T-type Ca(2+) channel.

Ultrastructural changes elicited by a non-ablative wrinkle reduction laser.

BACKGROUND AND OBJECTIVES: Cosmeceuticals, chemical peels and collagen injections are used to rejuvenate skin, but none of these methods is effective or permanent. Recently, laser resurfacing has been found to be effective, but the incidence of side effects is relatively high. Two years ago, the non-ablative wrinkle reduction laser (N-Lite, ICN Photonics, UK) was developed, and there have been several reports about its clinical effectiveness. In this study, we have investigated ultrastructural changes elicited by exposure to the N-Lite laser. STUDY DESIGN/MATERIALS AND METHODS: Eight adult volunteers were recruited for this study. They were treated with the N-Lite laser and 3-mm skin punch biopsies were obtained 3 hours, 1 day, 3 days, 1 week, 2 weeks, 4 weeks and 5 weeks after the laser exposure. These specimens were examined by electron microscopy. RESULTS: Three hours after the laser therapy, the capillaries showed endothelial cell edema with hemostasis and marked edema was observed around them. Neutrophils, monocytes and mast cells were observed in the extravascular dermis. These acute dermal inflammatory changes were observed until 1 week after the laser treatment. Two weeks after the laser treatment, the capillaries showed an almost normal structure, and dermal edema was not observed around them. New elastic fibers and collagen fibers had increased around the capillaries. Four weeks after the laser treatment, interstitial fibrosis was observed around the capillaries. CONCLUSIONS: N-Lite laser irradiation leads to interstitial fibrosis, especially around the capillaries, 4 weeks after the laser irradiation.