Biomedical subjects

E Scanlon

Publications and source records attributed to E Scanlon.

4 recordsLinked to original sources

PubMed2006

Squamous cell carcinoma of the larynx in HIV-positive patients: difficulties in diagnosis and management.

Patients who are infected with human immunodeficiency virus (HIV) are at increased risk of developing laryngeal squamous cell carcinoma. This malignancy on average appears in a younger age group at a more advanced stage and has a more aggressive course in HIV patients. These patients have difficult management challenges, diagnostically, in staging, and particularly in determining the optimal treatment for each individual patient because their underlying HIV infection can markedly increase morbidity associated with active treatments. They frequently have problems associated with swallowing both before and after treatment. We present two cases that highlight difficulties in the diagnosis and management of these patients as well as post-treatment complications, with particular emphasis on swallowing problems.

Adult↗

PubMed2000

Murine RARbeta4 displays reduced transactivation activity, lower affinity for retinoic acid, and no anti-AP1 activity.

The biological actions of retinoic acid (RA) are mediated by retinoic acid receptors (RARalpha, beta, and gamma) and retinoid X receptors (RXR alpha, beta, and gamma). Each of the RARs is expressed as four to seven different isoforms. Four isoforms of RAR beta (beta1, beta2, beta3, and beta4), which differ only in their N-terminal sequence (A domain) have been described. These RARbeta isoforms display a specific pattern of expression in developing and adult animals and are highly evolutionarily conserved suggesting that they mediate distinct cellular effects of vitamin A. Experiments were performed to examine directly the RA-binding activity, transactivation activity, and anti-AP1 activity of each of these four RARbeta isoforms. The results demonstrate that RARbeta1, beta2, and beta3 bind RA with a similar K(d) value, have a similar EC(50) value in RA-dependent transactivation assays and inhibit AP1 activity to a similar level. By contrast, RARbeta4 has an elevated K(d) for RA, an increased EC(50) value in RA-dependent transactivation assays and does not display the ability to inhibit AP1 activity. This provides additional evidence that at least one RAR isoform, RARbeta4, may mediate distinct activities within a cell. Furthermore, these data suggest that the presence of an A domain in RARbeta is important for modulating these activities of RARs.

Alitretinoin↗

PubMed1996

An objective assessment of speech and swallowing following free flap reconstruction for oral cavity cancers.

In this prospective study, eight consecutive patients underwent excision of oral cavity cancer and reconstruction with a microvascular free flap. Six patients had one pre- and two postoperative assessments of speech and swallowing at four to six weeks and four to six months respectively. One patient could not attend for the preoperative assessment and another for the first postoperative assessment. The speech assessment consisted of an intelligibility score and an articulation score. The swallowing assessment consisted of a videofluoroscopic examination. Five patients had an excellent postoperative speech assessment score, two had a moderate and one a poor result. Videofluoroscopy demonstrated minor swallowing problems preoperatively in one patient. Postoperatively, three patients had severe or moderate loss of control of bolus. Significant aspiration was detected in two and mild aspiration in one patient at the second postoperative assessment. The abnormalities of speech and swallowing were minor in the majority of the patients and the overall outlook was good. This information should be of value for preoperative counselling.

Adult↗

PubMed1992

Do cancers invade veins?

It is postulated that all malignant tumors spread in the same way. They invade through the basement membrane, spread through the interstitial compartment for variable distances, enter a lymphatic vessel through natural clefts, and reach the vascular compartment through lymphatic venous anastomoses or terminal lymphatics. The brain would seem to be an ideal site to test these ideas since it contains no lymphatic vessels. Injections of a well-characterized murine mammary tumor into the brains of 123 mice resulted in growth of the tumor in 82 mice (67%). Autopsy revealed only five cases in which there was distant tumor that had invaded beyond the brain.

Animals↗