PubMed Health⌕ Search

Biomedical subjects

L Willis

Publications and source records attributed to L Willis.

At least 19 recordsLinked to original sources
PubMed2005

Histopathologic indicators of breast cancer biology: insights from population mammographic screening.

Histopathologic features of breast cancer such as tumour size, grade and axillary lymph node (LN) status variably reflect tumour biology and time. Recent evidence suggests that the biological character of breast cancer is established at an early stage and has a major impact on clinical course. The aim of this study was to distinguish the impact of biology on breast cancer histopathology by comparing features of breast cancers diagnosed following population mammographic screening with prevalent vs incident detection and screening interval. Central histopathology review data from 1147 cases of ductal in situ and/or invasive breast cancer were examined. Size, grade and LN status of invasive cancers were positively correlated (P < 0.001). Prevalent invasive cancers were larger (P < 0.001) and more likely to be LN positive (P = 0.02) than incident cases, but grade was not associated with screening episode (P = 0.7). Screening interval for incident cancers was positively associated with invasive cancer size (P = 0.05) and LN status (P = 0.002) but not grade (P = 0.1). Together, these data indicate that biology and time both impact on size and LN status of invasive breast cancer, but grade reflects biology alone. In view of the clinical importance of breast cancer biology, grade as its most direct indicator assumes particular significance.

Adult↗
PubMed2005

Regulation of trophic factor expression by innervating target regions in intraocular double transplants.

Trophic factors have been found to play a significant role both in long-term survival processes and in more rapid and dynamic processes in the brain and spinal cord. However, little is known regarding the regulation of expression of growth factors, and how these proteins interact on a cell-to-cell basis. We have studied protein levels of one growth factor known to affect the noradrenergic innervation of the hippocampal formation, namely brain-derived neurotrophic factor (BDNF). The purpose of the present study was to determine if appropriate innervation or contact between the LC noradrenergic neurons and their target, the hippocampus, affects expression of this growth factor in either brain region. Fetal brain stem tissue, containing the LC, and hippocampal formation were dissected from embryonic day 17 rat fetuses and transplanted together or alone into the anterior chamber of the eye of adult Fisher 344 rats. The tissue was grown together for 6 weeks, after which the animals were sacrificed and ELISAs for BDNF were undertaken. Transplantation to the anterior chamber of the eye increased the expression of BDNF in the hippocampal but not the brain stem tissue, compared with levels observed in fetal and adult rats in vivo. In addition, double grafting with hippocampal tissue more than tripled BDNF levels in brain stem grafts and doubled BDNF levels in the hippocampal portion of double grafts compared with hippocampal single grafts. Triple grafts containing basal forebrain, hippocampus, and brain stem LC tissue increased brain stem and hippocampal BDNF levels even further. Colchicine treatment of LC-hippocampal double grafts gave rise to a significant decrease in hippocampal BDNF levels to levels seen in single hippocampal grafts, while only a partial reduction of BDNF levels was seen in the brain stem portion of the same double grafts treated with colchicine. The findings suggest that an appropriate hippocampal innervation or contact with its target tissues is essential for regulation of BDNF expression in the brain stem, and that retrograde transport of BDNF can occur between double grafted fetal tissues in oculo.

Animals↗
PubMed2001

MRI predictors of cognition in subcortical ischemic vascular disease and Alzheimer's disease.

BACKGROUND: Causes of cognitive impairment in subcortical ischemic vascular disease (SIVD) are less well understood than in AD, but have been thought to result from direct effects of subcortical lacunes and white matter lesions, perhaps related to disruption of important cortical-subcortical pathways. OBJECTIVE: To examine the relation between cognitive abilities and quantitative MRI measures of subcortical cerebrovascular disease and cortical and hippocampal atrophy. METHODS: Subjects were 157 participants in a multicenter study of SIVD and AD who included cognitively normal, cognitively impaired, and demented individuals with and without subcortical lacunar infarcts. Dependent variables were neuropsychological tests of global cognitive function, memory, language, and executive function. Independent variables were quantitative MRI measures of volume of lacunar infarcts in specific subcortical structures, volume of white matter lesion (WML), volume of cortical gray matter (cGM), and total hippocampal volume (HV). Multiple regression analyses were used to identify MRI predictors of cognition. RESULTS: Subcortical lacunes were not related to cognitive measures independent of effects of other MRI variables. WML was independently related to selected, timed measures. HV and cGM were strong and independent predictors of cognitive variables, with effects that did not differ in subjects with and without subcortical lacunes. CONCLUSIONS: Results suggest that cognitive impairment associated with subcortical ischemic vascular disease is primarily a result of associated hippocampal and cortical changes.

Aged↗
PubMed2001

Custody planning. a retrospective review of oncology patients who were single parents.

With rising numbers of single-parent families, a phenomenon becoming increasingly prevalent is the child orphaned by cancer. We sought to examine issues related to custody planning addressed prior to the patient's death. Ten deceased patients with minor children were identified. The contact person was administered a brief questionnaire regarding the minor children and custody issues. The study involved twenty children, ages ranging from 3-20, mean age 9.8. Only five of the ten families developed custody plans that were ultimately successful. One-half of the families reported the patient had suffered with this issue and almost one-half of the children were not aware of the custody plans that had been arranged for them. In 40% of the cases, the children ultimately went to people to whom the deceased parents were opposed. It is our belief that if we can improve these statistics, we might improve the quality of life of these families.

Child↗
PubMed2000

Home phototherapy for neonatal jaundice--technology and teamwork meeting consumer and service need.

32 babies with uncomplicated physiological jaundice received home phototherapy from a hospital/community team in southern Brisbane. All babies showed acceptable reductions in their serum bilirubin on home therapy, and none required hospital re-admission for phototherapy. Their families were highly satisfied with the home program, and recorded high levels of confidence in their therapeutic responsibilities. Community providers were able to deliver a high quality 24-hour service, integrated with appropriate neonatology support. The cost of delivering the home program was significantly less than a comparable hospital stay.

Bilirubin↗
PubMed1998

Ideomotor apraxia in early Alzheimer's disease: time and accuracy measures.

Twenty-six Alzheimer's disease (AD) and 42 healthy control (NC) subjects were evaluated with neuropsychological and apraxia batteries. ADs produced a greater range of error types, but did not differ from NCs in their most frequent error types. Hand sequencing ability contributed significantly to AD praxis with no predictors for NCs. Although groups did not differ in gesture time, the AD group had significantly longer response latencies for periods prior to gesture execution and the effect was prominent for transitive tasks and nondominant hand use. Results illustrate the sensitivity of timing measures in identifying abnormal praxis in early stages of AD.

Alzheimer Disease↗
PubMed1997

Impact of psychosocial factors on health outcomes in the elderly. A prospective study.

One hundred and thirty-five initially healthy men and women older than 65 years of age were studied prospectively to identify factors associated with health outcomes. At study onset, measures of personality, social interaction, and health locus of control were obtained while participants were still healthy. A reliable health outcome measure was developed, based on the annual objective coding of morbidity. Correlations between variables showed significant associations between age, a less independent personality trait, and poor health outcomes. Anxiety and low levels of social interaction were associated with poor health after 8 years. Gender and health locus of control were not significantly related to health outcomes. A path analysis showed significant direct paths between age and trait anxiety and 8-year health outcomes, and indirect paths between anxiety and extroversion and 8-year health, by way of social interaction. There was no evidence that social interaction mediated the effects of either anxiety or extroversion on health. The structure of psychosocial characteristics of the healthy elderly sample was revealed in the pattern of correlations between personality, social interaction, and locus of control.

Aged↗
PubMed1993

Leadership development for medical students--beyond the prescription pad.

BACKGROUND: Physicians are often perceived as leaders in their communities and are expected to participate in politics, business, and volunteer activities. Medical students receive little guidance about becoming effective community leaders. PROGRAM DESCRIPTION: We developed a leadership training program for medical students. Participation in the program was voluntary. The principal forum for this program was a dinner seminar series, which emphasized presentations by current community leaders and identification of leadership opportunities in which medical students could participate. PROGRAM EVALUATION: Information collected at the onset of the program identified the students' concern and priorities regarding leadership activities. Seventy-seven percent of participating students identified good communication skills as the most important quality of a leader. In identifying an issue in which physicians might become involved, students noted only medically related issues, such as access to health care. No long term evaluation data are available to assess the effect of this program. CONCLUSION: Medical school curricula should teach students the leadership skills they will need to participate in community activities.

Community Participation↗
PubMed1987

A prospective study of response to stressful life events in initially healthy elders.

Behavioral and physiological reactions to the stress of a major life crisis were studied prospectively in a group of healthy elderly individuals. Significant decreases in caloric intake, body weight, and lymphocyte count were found following the stressful event with a return toward baseline levels after a recovery period. Significant increases were found for psychological distress and serum cortisol. The results support the thesis that behavioral and physiological changes occur during an event perceived by an elderly person to be stressful and that such changes can have adverse effects on health.

Aged↗
PubMedDate not supplied

Acute myeloid leukemia in elderly adults.

One hundred and fifteen previously untreated adults aged over 60 years were referred to St Bartholomew's Hospital between 1978 and 1986 for management of acute myeloid leukemia (AML). Twenty-seven patients received symptomatic or palliative treatment only because combination chemotherapy was considered inappropriate. Eighty-eight patients received intensive chemotherapy with curative intent. There was a 48 per cent 'early death' rate and a 24 per cent incidence of resistant disease; complete remission (CR) was achieved in 25/88 patients (28 per cent). By multivariate analysis, a blast count less than 50 x 10(9)/l at presentation was the only factor predictive for achievement of CR whilst the latter and a presentation blast count less than 50 x 10(9)/l predicted for superior survival. Treatment was often curtailed on account of unacceptable toxicity; only 2/88 patients received the planned six cycles of treatment. Two patients died in CR. Four patients are alive in first CR at 3-9 years from treatment; one is alive in second CR following meningeal relapse. Overall survival was significantly worse than that of a contemporaneous group of adults aged 15-59 years treated at this hospital, but duration of CR was comparable. There are great difficulties involved in the intensive treatment of AML in elderly adults, but the major survival benefit gained by achieving CR should stimulate the search for better tolerated but still curative regimens.

Aged↗
PubMedDate not supplied

Practical classification of chin deformities.

A visually pleasing chin is an important component of facial harmony. This study was undertaken to introduce a practical classification of chin dysmorphology, which can be used to guide the surgeon toward the appropriate surgical approach to chin repair. Analysis of life-size photography, based on standard anthropometric measurements, was completed on 2,879 patients from 1981 to 1991. Six hundred eighty-four patients were noted to have normal occlusion with some form of chin deformity. Analysis of this group of patients identified seven categories of chin dysmorphism: Class I, macrogenia (n = 170, 24.9%); Class II, microgenia (n = 435, 63.6%); Class III, combination of macrogenia in one direction and microgenia in the other direction (n = 54, 7.9%); Class IV, asymmetry (n = 4, 0.6%); Class V, soft tissue ptosis ("witch's chin") (n = 13, 1.9%); Class VI, pseudomacrogenia (normal skeletal symphysis menti with excess soft tissue covering) (n = 5, 0.73%); and Class VII, pseudomicrogenia (long-face deformity producing clockwise rotation of the normal mandible) (n = 3, 0.4%). Having diagnosed the dysmorphism, logical surgical recommendations for lower face improvement were postulated. Only patients with Class II chin deformity can be corrected with augmentation. Classes I, III, and IV require an osteotomy of the chin. Classes V and VI benefit from soft tissue correction. Class VII deformity can be corrected with a maxillary osteotomy.

Adolescent↗