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Biomedical subjects

G Mason

Publications and source records attributed to G Mason.

At least 55 records · Page 3Linked to original sources
PubMed1995

Proton nuclear magnetic resonance spectroscopic imaging of human temporal lobe epilepsy at 4.1 T.

We performed proton magnetic resonance spectroscopic imaging (MRSI) at high magnetic field (4.1 T) to study N-acetylaspartate, creatine, and choline levels in the brains of normal control subjects and patients with intractable temporal lobe epilepsy. We compared the results of MRSI to those of other presurgical techniques to determine the sensitivity of this method in the lateralization of the epileptic focus. The normal hippocampal creatine-N-acetylaspartate ratio was 0.71 +/- 0.14 with no differences between left and right. Using the mean control hippocampal creatine-N-acetylaspartate ratio plus 2 standard deviations to identify statistically significant changes, we found lateralizing metabolic abnormalities corresponding to the operated temporal lobe in all patients. Four patients (40%) had contralateral abnormalities, and 2 of them had bilateral independent seizure onset confirmed by intracranial electroencephalographic studies. Statistically significant increases in the choline-N-acetylaspartate ratio in comparison to healthy volunteers were observed in 8 of the 10 patients. With the creatine-N-acetylaspartate ratio, MRSI demonstrated a 100% sensitivity compared to magnetic resonance imaging, which identified pathology in 70% of the patients. These findings suggest that proton MRSI yields a distinctive metabolic profile in patients with temporal lobe epilepsy and is sensitive in detecting bilateral metabolic abnormalities in some patients. These preliminary findings suggest that MRSI is more sensitive than magnetic resonance imaging in the lateralization of epileptic foci in temporal lobe epilepsy.

Adult↗
PubMed1995

Fungal eosinophilic pustular folliculitis.

A young woman presented with a persistent unilateral erosive and pustular plaque of the forearm. Repeated biopsy was required to make the diagnosis of a fungal cause for her eosinophilic pustular folliculitis.

Adult↗
PubMed1995

Keratotic basal cell carcinoma of the upper eyelid.

A 62 year old woman presented with two large slowly growing pedunculated tumours. These were excised from the lateral aspect of the upper eyelid and were found to be keratotic basal cell carcinomas.

Basal Cell Carcinoma↗
PubMed1995

Polydactylous Bowen's disease of the nail bed.

A case is presented with tender swelling and nail bed hyperplasia in 2 fingers. Histopathology revealed Bowen's disease in both fingers and after amputation, invasive squamous cell carcinoma in one finger.

Amputation, Surgical↗
PubMed1995

Plantar wart presenting as a cutaneous horn.

An elderly man presented with a longstanding, tender lesion on the sole of the foot. Clinically this was a cutaneous horn but biopsy revealed the features of a viral wart. The cytopathic effects of cutaneous human papillomaviruses are discussed.

Aged↗
PubMed1995

In search of effective programs to address students' emotional distress and behavioral problems. Part I: Defining the problem.

This article discusses the prevalence and seriousness of emotional difficulties and behavioral problems in students, with a special focus on high school students and the obstacles they encounter when addressing these problems. The educational, psychological, and medical literature which addressed the problem over the past five years was evaluated, and 22 references were selected. It was determined that the lack of consensus on the terms used to describe the problem prevented accurate assessment of its prevalence. However, one fifth to one third of the students were found to be affected, leading to serious educational, psychosocial, and economic difficulties--and more are likely to be affected in the 1990s. Since the school and mental health systems have not been entirely successful in addressing the problem, adolescents' patterns of seeking help indicate that peer support groups can be part of the solution. It was concluded that the enormity of the problem requires a low-cost gate-keeping mechanism to facilitate early identification and intervention. Thus, school peer-support programs, if proven effective, may complement traditional mental health services in addressing adolescents' emotional distress and behavioral problems.

Adolescent↗
PubMed1995

In search of effective programs to address students' emotional distress and behavioral problems. Part II: Critique of school- and community-based programs.

Part I of this article discussed the dimensions of students' emotional distress and behavioral problems and proposed school programs to address it. This section evaluates the school- and community-based programs advocated in educational, psychological, and psychiatric journals over the past five years. Twenty-nine articles were selected, and the programs classified by location, focus, and format. Their merits and limitations based on their results are discussed. This review found that (1) some programs poorly defined the study populations; (2) emotional distress was not included as a criterion; (3) a strictly behavioral approach or narrow focus on specific populations or issues prevailed. Only four programs used emotional expression and social support; (4) outcome measures focused on specific behaviors with only one study evaluating the emotional outcome; (5) none addressed the student's acceptance of the program; (6) only five measured the outcome beyond the immediate termination of the intervention, and only to a limited degree. While the programs reviewed support the likelihood that such interventions may be helpful, definitive conclusions which can be generalized to average high school students are still lacking. Recommendations for future school-based programs are proposed.

Adolescent↗
PubMed1994

Taking account of vaginal bleeding in screening for Down's syndrome.

OBJECTIVE: To derive a method for revising the risk of Down's syndrome in maternal serum marker screening when there is vaginal bleeding. The effect on screening performance of routinely allowing for the presence or absence of bleeding in all women is also assessed. DESIGN: Overview of published studies on the rate of reported vaginal bleeding in pregnancies with Down's syndrome, on the rate according to maternal age and on the association of bleeding with alpha-fetoprotein (AFP) level. The publications are supplemented with data on unconjugated oestriol (uE3), human chorionic gonadotrophin (hCG) and AFP levels in a consecutive series of screened women. SETTING: Routine Down's syndrome screening tests carried out on women having antenatal care at the St James's University Hospital, Leeds. SUBJECTS: Eight hundred and nine screened women. RESULTS: In five studies the rate of vaginal bleeding in Down's syndrome pregnancies was 1.7 times that in unaffected pregnancies on average. In three studies, the vaginal bleeding rate increased proportionally by 2.2% on average for each year of maternal age. Three studies and our own data were consistent with a 10% increase in the mean AFP level associated with vaginal bleeding, but it did not appear to materially alter uE3 and hCG levels or the standard deviations and correlation coefficients for any of the three analytes. An individual woman's risk was calculated by multiplying her age-specific odds of Down's syndrome by two likelihood ratios, one relating to the vaginal bleeding itself and one from the marker levels. Routine allowance for the presence or absence of vaginal bleeding was estimated to increase the detection rate by less than 1%. CONCLUSION: Our method is of clinical value in revising the risk when there is concern that vaginal bleeding might be responsible for a negative maternal serum Down's syndrome screening result. A policy of routinely incorporating information on vaginal bleeding in risk estimation for all women would have too small an effect on overall screening performance to recommend it.

Adult↗
PubMed1994

Plasma cell balanitis and vulvitis (of Zoon). A study of 10 cases.

We report six cases of plasma cell balanitis and four of plasma cell vulvitis. The patients' ages ranged from 26-88 years in males and 30-60 in females. All the men were uncircumcised and presented with a discharge and erythematous lesions on the glans penis and prepuce. In females the main presenting complaints were vulvar soreness, pruritus, smarting/burning, discharge and bleeding. Two were on hormone replacement therapy, two had undergone a mastectomy for carcinoma of the breast, and one was an insulin-dependent diabetic. Another patient subsequently developed diabetes mellitus. Topical and intralesional corticosteroid preparations resulted in satisfactory improvements in all cases, male and female. Two males subsequently underwent circumcision, which was curative.

Adult↗
PubMed1993

An unusual tricentric X chromosome detected prenatally.

We describe a female fetus with a de novo X chromosome rearrangement detected prenatally in both chorion villi and a pleural effusion. Chromosome painting showed the chromosome to be composed entirely of X chromosome material, while G-banding indicated a duplication of X short arms, four copies of the proximal long arm, and deletion of the distal long arm of the X. C-banding showed the presence of one active and two inactive centromeres and X-inactivation studies demonstrated the tricentric chromosome to be late replicating in all cells examined. The origin of this complex de novo rearrangement appears to have involved two separate breakage events, the first leading to the production of a dicentric X chromosome and the second generating the tricentric X.

Adult↗
PubMed1993

Central serotonergic changes following antidepressant treatment: a neuroendocrine assessment.

We employed a neuroendocrine challenge paradigm to study the effects of antidepressant treatment on serotonergic systems in depressed patients. We compared the maximum prolactin response to intravenous clomipramine (CMI) in depressed patients who responded to antidepressant treatment to that of nonresponders. Pretreatment baseline prolactin concentrations and pretreatment prolactin responses to clomipramine challenge were not different in responders compared to non-responders. However, following antidepressant treatment, the 6 responders demonstrated a significant change in their clomipramine challenge test results, as indicated by an increase in prolactin responses. In contrast, the 7 nonresponders did not demonstrate a change in their prolactin response to clomipramine challenge following treatment. These data support the hypothesis that serotonergic system dysfunction, as manifested by blunted prolactin response to clomipramine challenge, tends to normalize after successful treatment for depression, and that abnormal serotonergic function may be a state-dependent characteristic.

Adolescent↗