Clin Pediatr (Phila)
December 1988
A 2.7-year-old developmentally delayed boy diagnosed as having chronic lung disease, severe hyaline membrane disease, and persistent pulmonary hypertension with interstitial emphysema was referred in hopes of modifying his refusal to wear a mask during nebulized administrations of Chromolyn. The child was prescribed four 20-minute nebulized treatments daily but resisted treatment and removed the mask by turning his head and pushing the mask away with his hands.
View Article and Find Full Text PDFPrevious studies have demonstrated that brief pulses of selectively absorbed optical radiation can be used to confine thermal injury to pigmented targets within tissues. We performed studies in rabbits to assess the usefulness of this technique for selectively coagulating the colonic vasculature. By measuring the optical absorbance of rabbit colon with a spectrophotometer, it was determined that hemoglobin exhibits strong absorption relative to the rabbit colon at a wavelength of 577 nm.
View Article and Find Full Text PDFBovine cumulus-oocyte complexes (COC) (n = 4230) were used in this study to assess the effects of culture method, hormonal supplementation, and cumulus cell concentration on maturation, fertilization and development of resulting embryos. Five treatments were evaluated. 1) 10 COC/50-microliter drops under oil in TCM 199 supplemented with 10% heat-treated fetal calf serum, follicle-stimulating hormone (0.
View Article and Find Full Text PDFCapacitation of bovine sperm was evaluated by determining the ability of sperm to fertilize bovine oocytes in vitro and to undergo an acrosome reaction upon exposure to lysophosphatidylcholine (LC). Incubation of sperm with heparin (10 micrograms/ml) increased the percentage of oocytes fertilized, but this required exposing sperm to heparin for at least 4 h before adding them to oocytes. There was no effect on the percentage of motile or acrosome-reacted sperm after exposure of noncapacitated sperm to 100 micrograms/ml LC for 15 min.
View Article and Find Full Text PDFCoordination of professional services of behalf of children often hinges on the involvement of informed parents. The purposes of this study were to identify and experimentally and socially validate skills required of parents for effective communication with professionals. Target skills were identified on the basis of judges' social validation ratings of (a) sample interactions between parents and professionals and (b) the behaviors comprising a resultant task analysis.
View Article and Find Full Text PDFLaser radiation was employed to ablate venous thrombus or emboli with parameters that would not injure endovascular tissues. Output from a 482-nm, 1-microsec pulsed dye laser was delivered through a 320-microns-diameter fiber to in vitro samples of fresh thrombus (T), venous or pulmonary emboli (VE), inferior vena cava (IVC), pulmonary artery (PA), pulmonary valve, and endocardium (atrial and ventricular). The mean threshold fluences for ablation of T and VE were 1.
View Article and Find Full Text PDFThe safety and efficacy of pulsed tunable dye laser fragmentation of common bile duct stones was assessed in pigs. Laser pulses were conducted through a flexible quartz fiber that was in direct contact with stones that had been surgically implanted into the common bile duct. All calculi were rapidly fragmented into small pieces without significant damage to the common bile duct.
View Article and Find Full Text PDFDNA damage repaired by the excision repair system and measured as unscheduled DNA synthesis (UDS) was assessed in freshly excised human skin after 193 and 248 nm ultraviolet (UV)-excimer laser ablative incisions. Laser irradiation at 248 nm induced DNA damage throughout a zone of cells surrounding the ablated and heat-damaged area. In contrast, with 193 nm irradiation UDS was not detected in cells adjacent to the ablated area, even though DNA strongly absorbs this wavelength.
View Article and Find Full Text PDFThe feasibility of using lasers to fragment biliary calculi was examined in vitro. Flashlamp-pumped tunable dye lasers were coupled to small-diameter flexible quartz fibers that were placed in direct contact with biliary calculi. The minimum laser energy necessary to damage a calculus was measured for wavelengths between 450 and 700 nm and for pulse durations between 0.
View Article and Find Full Text PDFThe number of bovine spermatozoa separated in a swim-up procedure was quantified using an electronic cell counter. In an initial test of the swim-up procedure, non-frozen sperm samples with different ratios of live to dead cells were prepared and tested for the number of spermatozoa counted by the swim-up procedure. In ejaculates from six bulls, the number of spermatozoa swimming up was related to the number of live cells present (R2 = 0.
View Article and Find Full Text PDFThe pulsed dye laser was used to fragment ureteric calculi in 10 pig ureters, compared to electrohydraulic disintegration in six pig ureters. The stones were impacted in the proximal ureter and approached by rigid ureteroscopy. Four ureters did not have stones impacted but had ureteroscopes passed.
View Article and Find Full Text PDFThe properties of a laser which effect stone fragmentation have been studied. The pulsed dye laser emitting at 504 nm. in one microsecond duration pulses appears to be the optimum out of a wide range of parameters tested.
View Article and Find Full Text PDFIt has been shown recently that brief pulses of 577 nm radiation from the tunable dye laser are absorbed selectively by oxyhemoglobin. This absorption is associated with highly specific damage to superficial vascular plexus blood vessels in those with lightly pigmented (type I-II) skin. To determine whether pigmentary differences in the overlying epidermis influence this target specificity, we exposed both type I (fair) and type V (dark) normal human skin to varying radiant exposure doses over 1.
View Article and Find Full Text PDFNonacceptance of prescribed oral medications among young children hinders medical treatment. The literature pertaining to teaching children how to swallow pills or capsules is reviewed. In addition, a multiple case study demonstrating the efficacy of a brief, easy-to-implement procedure designed to promote capsule acceptance is presented.
View Article and Find Full Text PDFSystemic administration of the photoactive drug 8-methoxypsoralen to a group of mice bearing cutaneous allografts, followed by exposure to long-wave ultraviolet radiation (UVA, 320-400 nm) (PUVA) daily for 14 days at a site distant from the allograft, significantly increased the survival time of the allografts. This effect was seen both in donor-recipient combinations that differ at the major histocompatibility complex and in those differing only at minor histocompatibility loci. Treatment with 8-methoxypsoralen or long-wave UV radiation alone was ineffective in prolonging allograft survival, as were doses of mid-wave UV radiation (UVB, 280-320 nm) that produced greater inflammation than the PUVA protocol.
View Article and Find Full Text PDFThe pulsed dye laser, emitting at wavelengths of 504 nm. for 1 microsecond. at a frequency of 5 Hz.
View Article and Find Full Text PDFThe ability to increase laser-induced cutaneous blood vessel damage selectivity is dependent upon optimizing various intrinsic laser parameters. Varying the laser emission wavelength, pulse duration, and/or incident energy dosage allows the clinician potential improvement in the laser treatment of cutaneous small blood vessel processes such as port-wine hemangioma and telangiectasia. The pulsed dye laser at 577 nm and a pulse duration of 300 to 400 microseconds, incorporates desired laser parameters into its design.
View Article and Find Full Text PDFThe cytotoxicity of 193 and 248 nm excimer laser radiation was compared to that produced by a germicidal lamp (predominantly 254 nm) using Chinese hamster ovary cells (CHO), and a human diploid fibroblast line, AG-1522A. Excimer laser radiation at 248 nm (3.5 X 10(2) w/m2) and germicidal radiation (5.
View Article and Find Full Text PDFA new method is presented for controlled removal of the stratum corneum of human skin. An excimer laser (193 nm wavelength, 14 ns pulsewidth) was used to remove stratum corneum from in vitro human skin samples by an ablative process. The tritiated water (3H2O) permeability constant and electrical resistance of skin samples were measured in a diffusion chamber apparatus to quantify the enhancement of skin permeability.
View Article and Find Full Text PDFAnn Dermatol Venereol
September 1987
Since 1962, lasers have been used in dermatology and have become the first choice in the treatment of superficial, vascular ectasia. Lasers are unique sources of light; they are coherent, monochromatic, collimated and intense. By careful selection of wavelength, pulse duration, and intensity, it is often possible to selectively confine a laser effect to a specific histologic structure in tissue, depending upon the tissue properties.
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