The molecular mechanisms of laser-induced changes in the cell structure and function are not well known. The authors examined the effects of low-power laser irradiation on unnucleated pig blood platelets. The obtained results showed that laser irradiation (1-5 J) caused in blood platelets lipid peroxidation (measured as thiobarbituric acid reactive substances) and superoxide anion generation, c...

Directional dithering of a laser beam potentially limits the detection accuracy of a laser triangulation displacement probe. A theoretical analysis indicates that the measurement accuracy will linearly decrease as the laser dithering angle increases. To suppress laser dithering, a scheme for reduction of the influence of laser beam directional dithering in a laser triangulation displacement pro...

A new device consisting of a conventional fiberscope and a new TV system (model OTV-S5, Olympus Optical Co., Tokyo, Japan) has been developed to achieve accurate irradiation of laser light in photodynamic therapy for gastric cancer. This model has high resolution and sensitivity, and its signal can be transmitted by red, green and blue. In front of the CCD we inserted a special interference fil...

Standing-wave excitation of fluorescence is highly desirable in optical microscopy because it improves the axial resolution. We demonstrate here that multiplanar excitation of fluorescence by a standing wave can be produced in a single-spot laser scanning microscope by placing a plane reflector close to the specimen. We report here a variation in the intensity of fluorescence of successive plan...

Over-abundant populations of white-tailed deer (Odocoileus virginianus) create agricultural and human health and safety issues. The increased economic damage associated with locally overabundant deer populations accentuates the need for efficient techniques to mitigate the losses. Although red lasers can be an efficient tool for reducing damage caused by birds, they are not effective for deer b...

We investigate the physics of an optically trapped red blood cell under physiological conditions. When a single, live red blood cell, is placed in an optical trap, the normal biconcave disk shaped cell is observed to undergo a folding action and thereby take up a rod like shape. If such an RBC has any shape anisotropies due to perturbation through malarial infection or hyperosmotic stress, it i...

PURPOSE Angioscotomas are scotomata caused by vessel shadows. Their extent may be influenced by physiological and pharmacologic conditions and disease. In this study, the authors quantified angioscotomas in normal subjects using a fundus perimetry technique with a scanning laser ophthalmoscope. They further investigated the influence of two different wavelengths on scotoma depth. METHODS For ...

BACKGROUND Induction of delayed hypersensitivity reactions by red tattoos has been occasionally reported. Little is known about the inks used. Azo pigments have been implicated in some instances, but there is only one reported case involving quinacridones. OBJECTIVES To describe the clinical and pathological features and outcome of skin reactions induced by red tattoo pigments. PATIENTS, MA...

New BODIPY dyes with two 4-formylphenyl, 4-(2,2-dimethoxycarbonylvinyl)phenyl and 4-(2,2-dicyanovinyl)phenyl groups at the 3- and 5-positions have been successfully designed and synthesized via palladium-catalyzed coupling reaction or Knoevenagel-type condensations. Structural modification of the BODIPY core via conjugation-extending residues significantly affects the spectroscopy and photophys...

The purpose of this in vitro study was to evaluate the antimicrobial effect of photodynamic therapy on Streptococcus mutans (A TCC 25175) suspensions, using a red laser for one minute in combination with toluidine blue O (TBO) or methylene blue (MB). Both photosensitizers were used in three concentrations (25, 10 and 5 mg/L). The activity ofphotosensitizers and laser irradiation were tested sep...