Biomedical subjects

P F Castellanos

Publications and source records attributed to P F Castellanos.

6 recordsLinked to original sources

PubMed2000

Changes in the hypopharynx may suggest supraesophageal reflux disease.

Supraesophageal reflux disease is difficult to diagnose because its markers are not well defined. However, debate among gastroenterologists continues about the possibility that changes in the appearance and function of the hypopharynx can be valid indicators of atypical reflux disease. Detecting these indicators presents a challenge, albeit a necessary one, if reflux disease is to be identified and treated appropriately. This paper reviews the anatomical and functional characteristics of supraesophageal reflux disease.

Erythema↗

PubMed1997

Method and clinical results of a new transthyrotomy closure of the supraglottic larynx for the treatment of intractable aspiration.

A new procedure has been developed to surgically separate the pharynx from the trachea that employs the best features of the Montgomery technique, but restricts the closure to only the epiglottis and the aryepiglottic folds. The petiole of the epiglottis is plicated to the false vocal folds and the interarytenoid mucosa. It is performed entirely through a midline thyrotomy approach and avoids injury to any of the structures within the rima glottidis. It has been successfully performed on seven very ill patients to date. The surgical decision-making process involved, a complete description of the surgical procedure, and a summary of the patients' preoperative condition, workup, and outcomes are presented and discussed.

Adult↗

PubMed1994

Anatomic considerations in botulinum toxin type A therapy for spasmodic dysphonia.

Chemodenervation by injection of botulinum toxin type A into the vocal fold(s) has become the preferred treatment for patients with adductor spasmodic dysphonia. Injection may be done either perorally or transcutaneously; each method has its advocates and advantages. The authors have used the transcutaneous transcricothyroid membrane route exclusively with satisfactory results in more than 50 patients. Temporary breathliness and aspiration are common. The preferred injection site should be as close as possible to the motor end plates of the affected muscle. The thyroarytenoid muscle end plates are distributed throughout the muscle, whereas in the lateral cricoarytenoid muscle they are located in band in the center of the muscle. The transcutaneous injection site is below and posterior to the midpoint of the vibrating vocal fold as visualized by indirect laryngoscopy. The proximity of this site to the lateral cricoarytenoid muscle suggests that postinjection breathiness and aspiration may be related to spread of botulinum toxin type A to the lateral cricoarytenoid muscle. However, it is likely that thyroarytenoid muscle paresis is mainly responsible for this side effect and that the rapid clearing of the breathy dysphonia in the face of prolonged relief of spasmodic dysphonia symptoms suggests the action of an adaptive neural response, such as axonal sprouting. Further research of this subject is warranted.

Botulinum Toxins↗

PubMed1984

Evidence for peptide aggregation.

Evidence is presented that peptides may occur in aggregated form. Addition of 125I-Tyr-DSIP to serum resulted in four peaks after gel filtration chromatography on a column of Sephadex G-25. One of the peaks (C) eluted at the same position as the labeled peptide standard. Two Peaks (A and B) eluted before the standard and one (peak D) afterwards. The first peak (A) eluted at void volume, a position expected for labeled peptide bound to protein. The other two peaks (B and D), corresponding to smaller molecular size material, were greatly reduced by addition of glacial acetic acid or the chelating agent 1,10-phenanthroline before or even after mixing of the peptide with serum. Iron was one of the ions found to interact with 125I-Tyr-DSIP, and chromatography of a mixture of ferric chloride and peptide without serum resulted in the additional formation of peak B. A substantial portion of peaks A, B, and C (but not D) reacted with a specific DSIP antibody, indicating the presence of intact peptide. The results are consistent with the concept that peptides may occur in multiple forms.

Chromatography, Gel↗

PubMed1982

Differential penetration of DSIP peptides into rat brain.

Delta sleep-inducing peptide (DSIP) or five closely related peptides were injected peripherally and the levels of DSIP-like immunoreactivity measured in the brains of 100 g and 500 g rats decapitated a minute later after washout with 0.9% NaCl. Higher concentrations of immunoreactive material were found in brain tissue with injection of des Trp1-DSIP, D-Ala4-DSIP, and, after correction for cross-reactivity, with D-Ala4-DSIP-NH2 than with the other peptides. Both peptides substituted in the fourth position with D-alanine resulted in higher concentrations in 500 g rats than in 100 g rats, indicating a possible effect of age. The 5-10 fold greater brain to blood ratios of radioactivity after 125I-N-Tyr-DSIP than after 125-I radioiodinated serum albumin (RISA) provided additional evidence against non-specific leakage or contamination of the brains with substantial amounts of residual blood. The results suggest that penetration of the blood-brain barrier (BBB) by small amounts of peptides, at least DSIP peptides, may be somewhat selective.

Animals↗

PubMed1981

Radioimmunoassay of DSIP-like material in human blood: possible protein binding.

A radioimmunoassay (RIA) for DSIP-like material was established in unextracted human plasma. Most of the immunoreactivity was found in a "large" fraction while a much smaller amount co-eluted with DSIP from Sephadex as a "free" fraction. Both peaks progressively increased with increasing amounts of added DSIP. Acidification, but not treatment with charcoal-dextran, resulted in a relative decrease in the "large" peak and an increase in the "free" peak. This RIA, therefore, appears to measure both bound and free forms of DSIP-like immunoreactivity, the levels of which were higher at 4 p.m. than at 8 a.m.

Animals↗