Biomedical subjects
Publications and source records attributed to R J Triana.
Central adenoid cystic carcinomas are rare malignancies that are believed to arise in ectopic salivary gland tissue within the maxilla or mandible. We describe the diagnosis and treatment of a central adenoid cystic carcinoma in a 54-year-old man, which we believe was a recurrence of an earlier growth that had not been completely excised. We also present a review of the literature.
The aging process affects the underlying structural integrity of the eyelids as well as the overlying skin, muscle, and fat. Gravitational descent of the deep supporting soft tissues of the eyelid complex coupled with skin texture changes exemplified by loss of skin elasticity, solar actinic changes, and dynamic and static rhytids result in the aged eyelid. Surgery of the lower eyelid on the youthful face usually involves excisional fat sculpting without skin removal. Lower eyelid blepharoplasty performed on the mature face often requires excision of periorbital fat combined with some treatment of the lower eyelid skin. In the aging eyelid, the surgeon must also be prepared to address lower eyelid laxity to prevent the potential complications of lower eyelid retraction or scleral show.
In a rat model, we investigated the role of tumor necrosis factor (TNF) and interleukin-1 (IL-1) in endotoxin-induced middle ear effusions (MEEs). After the eustachian tube was obstructed, the middle ear was transtympanically injected with 35 microL of either 1) 1 mg/ mL lipopolysaccharide (LPS); 2) LPS and 100 micrograms TNF binding protein (TNFbp); 3) LPS and 1 microgram IL-1 receptor antagonist (IL-1ra); or 4) LPS, TNFbp, and IL-1ra. Every 2 hours, the fluid within the middle ear was collected, and the quantity of albumin in the fluid, an index of vascular leakage, was determined by enzyme-linked immunosorbent assay. After 6 hours, the middle ear was fixed for histologic analysis. The TNFbp significantly attenuated vascular extravasation into the middle ear. The IL-1ra did not significantly alter effusion development. These results indicate that TNF, but not IL-1, is a mediator of LPS-induced MEE. Therefore, TNFbp may represent a novel approach to the treatment of otitis media with effusion.
The congenic spontaneous hypertensive/National Institutes of Health (Bethesda, Md)-corpulent rat (SHR/N-cp) is a model for non-insulin-dependent diabetes mellitus. A previous study in our laboratory found significant loss of outer hair cells (OHC) in diabetic rats at 5.0 months of age. Our present study was designed to further evaluate the effects of the diabetic state on the inner ear in 10.5-month-old rats. The following comparisons were made: diabetic vs euglycemic control animals; obese vs lean phenotypes; and sucrose vs starch as the source of dietary carbohydrate. Cochleas were removed, fixed, stained, mounted on slides, and analyzed for OHC loss. We found a significant OHC loss in the cochleas of all diabetic animals. No statistical difference was found when comparing obese and lean phenotypes. Increased OHC loss was observed in all sucrose-fed vs starch-fed diabetic animals, although this increase was not statistically significant. Compared with an earlier study, an increase in OHC loss was also noted in the 10.5-month-old lean SHR/N-cp animals. Our results indicate that there is a relationship between non-insulin-dependent diabetes mellitus and inner ear damage and suggest that OHC loss is related to hyperglycemia and a genetic predisposition for glucose intolerance.
The association between diabetes mellitus and hearing impairment has been debated in many previous studies. The spontaneous hypertensive/NIH-corpulent (SHR/N-cp) rat has been shown to be a unique genetic model for non-insulin-dependent diabetes mellitus. Seventeen diabetic and 17 control young male rats were divided into groups according to diet and phenotype. The rats were fed either 54% of sucrose or 54% starch diets for 3.5 months and killed at 5 months. The cochleas were fixed, decalcified, dissected, and stained for hair cell counting. A significant loss of outer hair cells was noted in the diabetic obese (SHR/N-cp) animals when compared with the control obese (LA/N-cp) animals in every group. Although no significant difference was noted between the diabetic obese (SHR/N-cp) animals receiving the starch and sugar diets, the diabetic obese (SHR/N-cp) animals were more severely affected than the nondiabetic lean (SHR/N-cp) rats.
We used intravital fluorescent microscopy coupled with computerized video image processing to examine the cochlear microvasculature. In Mongolian gerbils the bulla was opened ventrally and a small window was made in the second turn of the cochlea. After fluorescein isothiocyanate-dextran administration, the radiating arterioles were video-recorded under X675 magnification. Computer determinations of arteriolar response to norepinephrine bitartrate (mixed alpha 1/alpha 2 agonist), phenylephrine hydrochloride (alpha 1 agonist), and UK 14,304 tartrate (alpha 2 agonist) were made at multiple dose levels over time. Findings were consistent with arteriolar constriction in response to alpha-adrenergic stimulation. The presence of alpha 1 and alpha 2 receptors was established, and a predominance of alpha 2 receptors in the cochlea was suggested.
The successful healing of the tympanic membrane (TM) following myringotomy or tympanoplasty is dependent upon the maintenance of the blood supply to the injured area of the TM. The blood supply of the TM is derived from the manubrial plexus and the peripheral plexus of vessels. This study concentrated on measuring blood flow derived from the manubrial vessels. The TM of the guinea pig was used as an in vivo model. Ten Outbred Hartley guinea pigs were anesthetized with Inactin 100 mg/kg, the common carotid artery cannulated, and FITC-dextran 150 injected intra-arterially. Blood pressures (mean 66.0 mmHg +/- 5.0 mmHg) and heart rates (330 bpm +/- 12.0 bpm) remained relatively constant throughout the experiment. Following injection of FITC-dextran 150, the TM was visualized under fluorescence microscopy and images recorded by video recorder; measurements of vessel diameter, blood velocity, and blood flow were made. Analysis of the in vivo studies revealed blood flow in the tympanic membrane to travel in two directions: down the manubrial artery towards the periphery and up the manubrial veins from vessels in the periphery. The manubrial artery divides and branches into a series of arcading vessels that extend towards the periphery of the TM. Manubrial artery diameter was measured (mean 0.0521 mm +/- 0.0004 mm) and blood flow calculated (mean 0.0439 mm3/min +/- 0.0007 mm3/min). Blood flow from the manubrial artery supplying the superior quadrants (0.18 mm3/min +/- 0.01) was statistically greater when compared to the blood flow in the inferior quadrants (0.08 mm3/min +/- 0.007) (p less than .001).
OBJECTIVE: To evaluate and discuss the free flap reconstructive options for patients with partial and total maxillectomy defects. DESIGN: Retrospective review of cases. SETTING: Two tertiary referral centers. PATIENTS: Fifty-one patients had partial or total maxillectomy defects resulting from oncologic surgical resection, and 7 had partial maxillectomy defects resulting from trauma. Inferior or partial maxillectomy defects included 10 anterior arch and hemipalate defects and 12 subtotal or total palate defects. Total maxillectomy defects with and without orbital exenteration included 36 maxilla defects with hemipalate and malar eminence. INTERVENTION: There were 11 fibula, 14 rectus abdominis, 9 scapular, 10 radial forearm, 5 latissimus dorsi, and 13 combination latissimus dorsi and scapular flaps. MAIN OUTCOME MEASURES: Separation of the oral cavity from the sinonasal cavities, diet, type of dental restoration, type of orbital restoration, speech intelligibility, and complications. RESULTS: Only 1 flap failure was reported. There was loss of bone in 2 flaps and loss of the skin paddle in 1 flap. All palatal defects were sealed by the separation of the oral and sinonasal cavities. Thirty-eight patients were able to eat a regular diet while the remaining patients maintained a soft diet. All patients conversed on the telephone without difficulty in intelligibility. Eight patients had an implant-borne dental prosthetic, and 30 patients had a conventional partial prosthetic. Orbit restoration was achieved in 2 patients with an implant-borne prosthetic, and 6 patients retained a standard orbit prosthetic. CONCLUSIONS: Free flap reconstruction of the maxilla creates reproducible permanent separation of the oral and sinonasal cavities in a single-stage procedure. In addition, there exists the potential for dental rehabilitation with restoration of masticatory and phonatory function. Free flap reconstruction also provides a good cosmetic result, which improves patients' outlook and contributes to their overall well-being. Reconstructive flaps are designed to fit specific maxillary defects and patient needs to provide optimally functional and cosmetic results.