Granular cell tumors of the larynx.
Granular cell tumor is a rare neoplasm that may involve the larynx. It is almost always benign. Laryngologists should be familiar with this unusual tumor, its implications and appropriate treatment.
Adult↗
Biomedical subjects
R Ossoff
Publications and source records attributed to R Ossoff.
Tissue ablation by a free-electron laser tuned to the amide II band.
Efforts to ablate soft tissue with conventional lasers have been limited by collateral damage and by concern over potential photochemical effects. Motivated by the thermal-confinement model, past infrared investigations targeted the OH-stretch mode of water with fast pulses from lasers emitting near 3,000 nm (refs 1, 7-9). What does a free-electron laser offer for the investigation of tissue ablation? Operating at non-photochemical single-photon energies, these infrared sources can produce trains of picosecond pulses tunable to the vibrational modes of proteins, lipids and/or water. We report here that targeting free-electron laser radiation to the amide II band of proteins leads to tissue ablation characterized by minimal collateral damage while maintaining a substantial ablation rate. To account for these observations we propose a novel ablation mechanism based on compromising tissue through resonant denaturation of structural proteins.
Amides↗
Role of immersion refractometry for investigating laser-induced effects in cells.
The broad background of scattered light observed in spectra of cell suspensions is reduced by factors of up to 20 by immersion refractometry allowing for improved spectroscopic determination of the absorption properties of cells in the 325-820 nm range. Refractive-index matched spectra of E. coli C1a exhibit a set of resonant features near 422, 561, and 582 nm. Exposure wavelengths are chosen based on this spectrum and cell viability is investigated in E. coli suspensions exposed to 350, 400, 422, 440, and 700 nm radiation delivered in nanosecond pulses with total doses from 500 millijoules to 60 Joules. We observe a loss in cell viability for doses greater than 1 Joule at 422 nm and for all doses at other wavelengths; exposures of less than 1 Joule at 422 nm enhance growth. Excluding exposures at wavelengths within the resonant feature, longer wavelengths are less effective at reducing the viability of E. coli C1a. This indicates the occurrence of at least two absorption processes.
Absorption↗
Reconstruction for large septal perforations.
Reconstruction of large nasoseptal perforations is often dismissed as surgically unfeasible. The insertion of polymer prostheses for amelioration of symptoms has substituted for surgical repair. Despite the important progress that has recently been made, troublesome defects, eg, the repair of 2 x 4-cm losses, are considered surgically unapproachable. One of us (M.S.K.), during the past seven years, has treated these defects with techniques developed in skull base surgery and, more recently, in maxillofacial and craniofacial surgery. The wide exposure achieved has permitted the use of large intranasal flaps for one-step repair. Photographs, graphic illustrations, and cadaver dissections are used to present the techniques. The literature is reviewed. Clinical material is reviewed, and special consideration is given to the problems of intranasal scarring and flap blood supply. The techniques used represent an evolutionary synthesis and implementation of surgical principles rather than a new technique. Nevertheless, the tools are now at hand for all to approach these large perforations with confidence.
Cicatrix↗
The staphylococcal scalded-skin syndrome versus erythema multiforme.
This article reports a case of scalded-skin syndrome in a young child. Characterized by a generalized exfoliative dermatitis resembling scalded skin, the disease may involve the oral mucosa and must be differentiated from Stevens-Johnson syndrome (erythema multiforme). Since the etiology is specific, the disease can be treated with antibiotics with dramatic results.
Administration, Oral↗
Blood viscosity reduction in negative charged capillary tubes.
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Blood Viscosity↗