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Biomedical subjects

M J Davidson

Publications and source records attributed to M J Davidson.

At least 19 recordsLinked to original sources
PubMed1997

High-grade papillary cystadenocarcinoma of the tongue.

AIMS: Salivary gland tumours of the tongue are rare. The most common type is low-grade mucoepidermoid carcinoma followed by adenoid cystic carcinoma. Papillary cystadenocarcinoma of salivary glands are uncommon lesions with low-grade mucoepidermoid carcinoma followed by adenoid cystic carcinoma. Papillary cystadenocarcinoma of salivary glands are uncommon lesions with low-grade histological and clinical features. We report a high-grade papillary cystadenocarcinoma in an 80-year-old man who presented with a tongue mass and metastatic disease in the neck. METHODS AND RESULTS: He was treated with partial glossectomy and bilateral neck dissection but developed local and regional recurrences 6 months later. The tumour had a prominent cystic appearance and had areas of necrosis. The cyst lumen was occupied by numerous papillae lined by pseudostratified columnar cells with a high nuclear-cytoplasmic ratio. The cytoplasm was eosinophilic, the nuclei were pleomorphic and exhibited irregular nuclear membranes, vesicular chromatin and prominent eosinophilic nucleoli. The mitotic activity was high and there were occasional abnormal mitotic figures. Metastatic carcinoma was present in four lymph nodes. The differential diagnosis of this unusual lesion includes cystadenoma, salivary duct carcinoma and metastases. CONCLUSIONS: This case and a review of the literature indicates that papillary cystadenocarcinomas of salivary gland origin exhibit a wider morphologic spectrum than described in the latest World Health Organization (WHO) classification which defines these lesions as low-grade neoplasms.

Aged↗
PubMed1997

Predicting postlaryngectomy voice outcome in an era of primary tracheoesophageal fistulization: a retrospective evaluation.

OBJECTIVES: Not all laryngectomees appear to have the same potential to develop functional spoken communication. Our goal was to evaluate voice outcome in different functional subgroups of laryngectomees and to identify physical and demographic factors associated with success and failure to achieve functional spoken communication. DESIGN: Retrospective chart review. SETTING: Surgery was performed at a tertiary care hospital. Multidisciplinary follow-up was conducted at weekly head and neck clinics held at the associated regional cancer centre. Voice rehabilitation procedures took place in both settings. PATIENTS: Sixty-four consecutive patients who had undergone total laryngectomy during the era of primary tracheoesophageal fistulization (TEF) at this facility. Patients were subdivided into four groups according to whether they had undergone primary TEF, or whether this had been contraindicated by locoregional factors of TEF candidacy/performance status, or both. INTERVENTIONS: Primary TEF was performed whenever technically feasible and traditional TEF candidacy criteria were met. Voice rehabilitation procedures were initiated prior to discharge. OUTCOME MEASURES: A judgement of voice outcome was assigned based on documentation on at least one of three patient treatment records by a physician or speech-language pathologist that a patient had demonstrated functional spoken communication within the clinical setting. RESULTS: Forty-five of 64 patients (70%) achieved functional spoken communication. Six laryngectomized subgroups were ultimately identified and characterized. Voice outcome varied considerably between these subgroups. Prelaryngectomy communication status and age emerged as predictors of voice outcome. CONCLUSIONS: Voice outcome is related to several factors present prior to or at laryngectomy. Different combinations of such factors create various postlaryngectomy recovery streams for which voice outcome may be predicted more specifically.

Adult↗
PubMed1996

Phenotypic characterization of individuals with 30-40 CAG repeats in the Huntington disease (HD) gene reveals HD cases with 36 repeats and apparently normal elderly individuals with 36-39 repeats.

Abnormal CAG expansions in the IT-15 gene are associated with Huntington disease (HD). In the diagnostic setting it is necessary to define the limits of the CAG size ranges on normal and HD-associated chromosomes. Most large analyses that defined the limits of the normal and pathological size ranges employed PCR assays, which included the CAG repeats and a CCG repeat tract that was thought to be invariant. Many of these experiments found an overlap between the normal and disease size ranges. Subsequent findings that the CCG repeats vary by 8 trinucleotide lengths suggested that the limits of the normal and disease size ranges should be reevaluated with assays that exclude the CCG polymorphism. Since patients with between 30 and 40 repeats are rare, a consortium was assembled to collect such individuals. All 178 samples were reanalyzed in Cambridge by using assays specific for the CAG repeats. We have optimized methods for reliable sizing of CAG repeats and show cases that demonstrate the dangers of using PCR assays that include both the CAG and CCG polymorphisms. Seven HD patients had 36 repeats, which confirms that this allele is associated with disease. Individuals without apparent symptoms or signs of HD were found at 36 repeats (aged 74, 78, 79, and 87 years), 37 repeats (aged 69 years), 38 repeats (aged 69 and 90 years), and 39 repeats (aged 67, 90, and 95 years). The detailed case histories of an exceptional case from this series will be presented: a 95-year-old man with 39 repeats who did not have classical features of HD. The apparently healthy survival into old age of some individuals with 36-39 repeats suggests that the HD mutation may not always be fully penetrant.

Adult↗
PubMed1993

Huntington's disease in Grampian region: correlation of the CAG repeat number and the age of onset of the disease.

The identification of an unstable trinucleotide repeat as the mutation responsible for Huntington's disease (HD) has given the hope that additional information can be provided about age of onset and mode of action of the mutated gene. We present in this paper results of a clinical and molecular study of 82 patients affected with HD from 46 pedigrees within the Grampian region, Scotland. Our results show a correlation between age of onset and size of the CAG expansion. This study has produced no overlap in mutation size between affected and unaffected alleles. The sex of the parent transmitting the mutated allele and the size of the normal allele have no significant effect on the clinical features of the disease. In the three juvenile cases the affected parent was the father but the number of cases is too small to produce statistical significance. An increase in the CAG repeat size is shown in the transmission of the gene in five cases, accompanied by an earlier age of onset in four; in three of these cases, the affected parent was the father. Eleven sib pairs were studied and there is a negative correlation between the difference in age at onset and the difference in repeat size. Thus there is some evidence of a relationship, but this is not statistically significant because of the small numbers involved. The presence of the same or different normal allele had no effect on age of onset in this small group. We suggest that additional factors, as yet unrecognised, influence the age of onset and clinical presentation of HD.

Adolescent↗
PubMed1993

Visual display units and pregnancy outcome: a prospective study.

This paper presents the results of a prospective study of the impact of work with visual display units (VDUs) and associated ergonomic and stress variables on pregnancy outcome and infertility. An apparent relationship between VDU use and pregnancy outcome in retrospective data probably reflected the operation of recall bias. Prospective data did not reveal any evidence for an adverse effect of VDUs on pregnancy in this sample, or any mechanism by which such an effect could occur. There was no evidence for any effect of VDU use on infertility. Implications for working women and future research are also presented.

Adolescent↗
PubMed1991

Ewing's sarcoma of the temporal bone. A case report.

An 11-year-old girl with a primary Ewing's sarcoma in the squamous temporal bone is described, and differential diagnosis and management are discussed. The membranous bones of the skull are rare sites for a primary Ewing's sarcoma; the squamous temporal bone has not been previously described as a primary site.

Child↗
PubMed1991

The use of computed tomography in the management of facial trauma by British oral and maxillofacial surgeons.

A survey of 184 British oral and maxillofacial surgeons on their use of computed tomography (CT) in the management of craniofacial trauma showed that the majority of the 116 surgeons who replied used this form of imaging for frontal, nasoethmoidal, and orbital fractures. Only 6% of respondents reported no advantage in CT imaging over plain radiography. The access to CT scanners and the value of the reports in the management of patients was rated as satisfactory by 75% of respondents, and a similar percentage reported that CT service was becoming increasingly available to their units.

Consultants↗
PubMed1991

Prosthetic plate mandibular reconstruction.

The head and neck surgeon may choose one of several available methods to reconstruct the mandible following tumor ablation. This article discusses the use of metallic mandibular prostheses, the indications for alloplastic mandibular reconstruction, techniques of plate application (AO and THRP), and associated complications.

Bone Plates↗
PubMed1990

Computed tomography in the diagnosis of maxillofacial trauma.

A study of 34 patients who were investigated for maxillofacial trauma using high resolution computed tomography (CT) scanning is presented. The areas where this increasingly available technique offers more accurate information than conventional plain radiographs are discussed.

Eye Injuries↗
PubMed1990

Thin section computed tomography in the evaluation of naso-ethmoidal trauma.

We reviewed the computed tomography (CT) appearances, plain film radiographs and clinical findings of 17 patients who suffered fractures of the naso-ethmoidal complex. Six patients (35%) with diplopia were noted on CT to have lateral displacement of medial orbital wall fragments into the orbit (medial wall 'blow-in' fractures) leading to displacement of the globe or extra-ocular muscles. Medial displacement of ethmoid bone fragments (medial wall 'blow-out' fractures) with medial rectus entrapment was noted in a further two cases (11%) also. Multiple associated facial fractures were seen in all but one case with CT evidence of frontal bone fracture and intracranial injury in 12 (70%) patients. CT was judged to add valuable information to clinical findings and plain film radiography and was especially helpful where marked soft tissue swelling precluded detailed physical examination of the naso-orbital region. The CT features of naso-ethmoidal trauma are illustrated and discussed and the advantages of CT in the pre-operative evaluation of such injuries are emphasised.

Diplopia↗
PubMed1982

Stress in the police service.

In this study, the sources of stress among supervisory police officers were explored. It was found that one of the major sources of stress across all managerial levels among the police was the perception that the police service was inhibited by unnecessary bureaucratic and outside obstacles, e.g., increased paperwork, interdepartmental politics, lack of adequate planning and resources and the inability of the courts to prosecute offenders. It was also found that junior and middle supervisory police officers were adversely affected by lack of available manpower and long working hours, whereas senior officers were affected more by the conflict in maintaining positive policing as well as good community relations.

Adult↗
PubMed1981

Metoprolol overdose.

We report the first two documented cases of the deliberate metoprolol overdose occurring in the United States, one of which eventually proved fatal. The potentially lethal cardiotoxic effects of this drug are illustrated and correlated with the blood and tissue levels of metoprolol. We emphasize the often sudden and rapid clinical deterioration which excessive ingestion of this drug may produce, and the need for close, careful supervision and monitoring of these patients.

Adult↗