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Biomedical subjects

E Williams

Publications and source records attributed to E Williams.

At least 109 records · Page 6Linked to original sources
PubMed1997

The role of surgical ligation of patent ductus arteriosus in the era of the Rashkind device.

BACKGROUND: The role of surgery in managing patent ductus arteriosus (PDA) was studied in the era of the Rashkind double-umbrella device. METHODS: All 354 patients with PDA referred to our center in a 5-year period were included in this report. Of the 354 patients, 236 underwent cardiac catheterization with the intent of transcatheter PDA closure, and 118 had surgical intervention. RESULTS: In 46 (19.5%) of the 236 patients having cardiac catheterization, the procedure either was abandoned or failed. Color Doppler echocardiography demonstrated total occlusion of the ductus after 24 hours in 97 patients (41%) in the cardiac catheterization group. An additional 20 patients had no residual leaks at follow-up. Twenty other patients underwent reocclusion because of a residual shunt. Thus, of the 236 patients, 137 (58%) had successful complete closure of the PDA. Surgical PDA ligation was performed in 118 patients as the initial procedure and in 26 of the 46 patients in whom transcatheter closure was abandoned. If the remaining 20 patients in whom transcatheter closure failed are added to the 144 patients who underwent PDA ligation, the percentage having surgical intervention versus transcatheter occlusion is higher than 46%. CONCLUSIONS: Our data suggest that surgery plays a major role in the management of patients with PDA despite the advent of new interventional catheterization techniques.

Adolescent↗
PubMed1997

An evaluation of initiatives to improve family planning use by African-American adolescents.

Teen pregnancies in the United States have reached epidemic proportions, and consequently, efforts to promote family planning among adolescents have increased. At the Orleans Parish Family Planning Clinic in New Orleans, Louisiana, adolescent-specific initiatives were implemented to improve understanding of family planning services and promote contraceptive use. Since 92% of the patients are African American, the study population was limited to this group. This study examines the efficacy of two initiatives (i.e., orientation sessions and 3-month booster visits conducted in adolescent-specific clinics) for improving initiation and continuation of family planning services among African-American adolescent women. Initiation of services was compared among those who attended the orientation session and those who did not attend. Continuation of services was determined by attendance of the annual visit for those who attended the 3-month follow-up visit and those who did not attend. Of 737 teens entering into the clinic, the mean age was 16 years, 95% were enrolled in school, 23% attended the orientation session, and 71% initiated services. Of the 507 who initiated services and who underwent follow-up for at least 12 months, 29% attended the 3-month follow-up visit and 32% attended an annual visit. Attendance of the orientation session was associated with initiation of services and attendance of the 3-month booster visits was associated with attendance of the annual visit in multivariate logistic regression. Simple and cost-effective techniques such as orientation sessions and follow-up visits conducted in adolescent clinics can improve initiation of family planning and compliance among adolescents.

Adolescent↗
PubMed1997

Problems found in the over-75s by the annual health check.

BACKGROUND: Research into the health of elderly people has found problems unknown to their general practitioners. It was anticipated that annual checks, as required by the 1990 general practitioner contract, would help to detect these problems, yet the value of these checks has been questioned. AIM: To investigate the problems found by general practice contractual annual checks of the over-75s and the consequent actions taken; to identify patient, demographic or practice characteristics associated with the discovery of problems. METHOD: In 40 practices, information was collected on patients over 75 years of age receiving a health check during a 3-month period. Practices used their normal methods of recruitment and assessment. Practice staff were interviewed to find how assessments were organized. RESULTS: Practices saw a mean of 12% of their over-75s during the study; 44% were found to have at least one problem. Action was taken to help resolve problems in 82% of patients with a problem. The most prevalent problems related to physical condition, and fewer functional problems than expected were found. There were large differences between practices in the proportions of elderly patients seen for a check and the proportion found to have problems; these were not attributable to practice size or demography. Multivariate analysis showed that practice or patient characteristics were poor predictors of finding problems. CONCLUSION: The argument in favour of conducting annual checks is supported by the finding that nearly half the patients assessed were found to have problems for which some action was taken. Some practices could increase their rate of uptake by modifying the organization of invitations for checks. More problems may be found by adopting a more functionally based assessment.

Aged↗
PubMed1997

The cost and benefit of prophylaxis against deep vein thrombosis in elective hip replacement. DVT/PE Prophylaxis Consensus Forum.

UNLABELLED: A consensus forum was convened to evaluate the economic considerations associated with prophylaxis against thrombo-embolic disease in patients undergoing hip replacement therapy in South Africa. This forum consists of orthopaedic surgeons, vascular surgeons and a statistician. METHODS: The forum was instructed to evaluate the economic costs of the commonly used forms of prophylaxis of thrombo-embolism in patients undergoing hip replacement surgery in South Africa, looking at short-term events only. The methods used for the prophylaxis of thrombo-embolism in South Africa were determined by a postal survey. A decision tree was constructed to determine the events that will occur after a clinical decision to use no prophylaxis. The probabilities of these events were then determined. Protocols for and costs of prophylaxis and treatment were established. With the decision tree and these costs, the cost of the various modalities of prophylaxis was then determined. RESULTS: The probability, determined by the forum, of developing a deep-vein thrombosis (DVT) when no prophylaxis is used was 0.5, with a mortality rate of 2.1%. The cost of this decision was R875. No prophylaxis given, but a venogram performed on day 7, reduced the mortality rate to 0.7%; however, this cost R3 017. The cost of low-molecular-weight heparin was R1 223 (probability 0.26, mortality rate 1.1%), while unfractionated heparin with a graduated compression stocking (GCS) cost R1 351 (probability 0.24, mortality rate 1%). Aspirin with a GCS cost R777 (probability 0.35, mortality rate 1.5%).

Anticoagulants↗
PubMed1997

Physician job satisfaction: developing a model using qualitative data. SGIM Career Satisfaction Study Group.

The purpose of this study was to develop a current and comprehensive model of physician job satisfaction. Information was gathered by (1) analysis of open-ended responses from a large group practice physician survey in 1988, and (2) analysis of focus group data of diverse physician subgroups from 1995. Participants were 302 physicians from large-group practices and 26 participants in six focus groups of HMO, women, minority, and inner-city physicians. Data were used to develop a comprehensive model of physician job satisfaction. The large group practice survey data supported the key importance of day-to-day practice environment and relationships with patients and physician peers. Future concerns focused on the effect of managed care on the physician-patient relationship and the ability of physicians to provide quality care. Focus groups provided contemporary data on physician job satisfaction, reinforcing the centrality of relationships as well as special issues for diverse physician subgroups of practicing physicians. New variables that relate to physician job satisfaction have emerged from economic and organizational changes in medicine and from increasing heterogeneity of physicians with respect to gender, ethnicity, and type of practice. A more comprehensive model of physician job satisfaction may enable individual physicians and health care organizations to better understand and improve physician work life.

Adult↗
PubMed1996

Ventral striatopallidothalamic projection: IV. Relative involvements of neurochemically distinct subterritories in the ventral pallidum and adjacent parts of the rostroventral forebrain.

Retrograde and anterograde tract-tracing studies were carried out to determine whether the capacity of the nucleus accumbens to influence the thalamic mediodorsal nucleus via ventral striatopallidothalamic connections disproportionately favors the shell over the core subterritory. After injections of Fluoro-Gold into the mediodorsal thalamic nucleus, retrogradely labeled neurons were detected in sections also processed for calbindin-D 28-kD and neurotensin immunoreactivities to facilitate identification of subterritories in the ventral pallidum. Fluoro-Gold-labeled cells were counted in series of sections cut through the ventral pallidum, rostral globus pallidus, nucleus of the vertical limb of the diagonal band, preoptic region, lateral hypothalamus, and the sublenticular gray region, including parts of the extended amygdala. Data were expressed as cells/unit area and as percentages of all labeled forebrain cells. Mediodorsal nucleus-projecting rostroventral forebrain neurons were most numerous in the ventromedial part of the subcommissural ventral pallidum and pallidal parts of the olfactory tubercle. Few were observed in the dorsolateral part of the subcommissural ventral pallidum. In addition, following injections into the ventral pallidum, anterogradely transported biotinylated dextran amine was evaluated in sections processed for calbindin or tyrosine hydroxylase immunoreactivities. Injection into the ventromedial part of the subcommissural ventral pallidum resulted in robust anterograde labeling of the medial segment of the mediodorsal nucleus and ventral tegmental area and weak labeling of the substantia nigra and subthalamic nucleus. Conversely, after injection into the dorsolateral part of the subcommissural ventral pallidum, anterograde labeling was weak in the mediodorsal nucleus and ventral tegmental area, but robust in the substantia nigra and subthalamic nucleus. The results are consistent with a predominant accumbens shell influence on the mediodorsal nucleus and with cortico-ventral striatopallidal-thalamocortical pathways that begin and end in different parts of the frontal lobe.

Amines↗
PubMed1996

Effects of MF-268, a new cholinesterase inhibitor, on acetylcholine and biogenic amines in rat cortex.

MF-268 bitartrate [(3a S, 8a R)-1,2,3,3a,8,8a-hexahydro-1,3a,8-trimethylpyrrolo[2,3-b]indol- 5-ol[8-(cis2,-6-dimethyl-morpholin-4-yl)octyl]-carbamate L-bitartrate hydrate; Mediolanum Farmaceutici, Milan, Italy] is a pseudo-reversible carbamate-type cholinesterase inhibitor (ChEI) which interacts with the catalytic and regulatory anionic site of the enzyme. Its effects on extracellular levels of acetylcholine (ACh), norepinephrine (NE), dopamine (DA), and serotonin (5-HT, 5-hydroxytryptamine) were studied in rat cortex by using a microdialysis technique coupled with high-performance liquid chromatography-electrochemical detection (HPLC-ECD). Conscious, freely moving rats were systemically [per os (p.o.) and subcutaneously (s.c.)] administered MF-268 with no ChEI in the probe. Cholinesterase inhibition in brain was assayed in parallel experiments. Oral administration of MF-268 (0.5, 2.0, and 5.0 mg/kg) produced a significant increase of extracellular ACh in cortex; the maximal increase was 300% [not significant (n.s.)], 460% and 1,200%, respectively. Maximal cholinesterase (ChE) inhibition was 2.3% (n.s.) at 9 hr and 9.7% (P < .05) at 12 hr after the 2.0 and 5.0 mg/kg doses, respectively. Norepinephrine and DA levels were increased 180% and 100% after the 5.0 mg/kg dose, respectively; 100% and 60% after the 2.0 mg/kg dose, respectively; and 70% for both amines after the 0.5 mg/kg dose, respectively. The elevation lasted at least 5 hr with the 2.0 and 5.0 mg/kg doses. There were no major changes in 5-HT levels at these three doses. Subcutaneous administration (0.5 and 2.0 mg/kg) produced a maximal 360% (5.5 hr) and 2,500% (5 hr) increase in extracellular ACh, respectively. Maximal ChE inhibition was 13% (0.5 mg/kg) and 41% (2.0 mg/kg). Neither 0.5 nor 2.0 mg/kg produced a consistent modification of NE. Only a transient increase in DA was seen with the 0.5 mg/kg dose. There were no changes in 5-HT levels at these two doses. MF-268-treated animals showed slight cholinergic side effects (chewing, tremor) at both doses. MF-268 administered intracortically through the microdialysis probe at a concentration of 50 microM induced a 5,900% increase in ACh levels at 6 hr. This effect started 30 min after injection and continued throughout the period of administration. MF-268 produced a significant decrease in NE levels (-44%) starting at 30 min, and a slight but significant increase in DA levels of 45% at 2.5 hr. A significant increase of 5-HT (58%) was also observed starting at 4 hr. Slight symptoms of cholinergic toxicity were observed during intracortical administration.

Acetylcholine↗
PubMed1996

The effect of the selective reversible acetylcholinesterase inhibitor E2020 on extracellular acetylcholine and biogenic amine levels in rat cortex.

E2020 is a piperidine cholinesterase inhibitor (ChEI) which is structurally distinct from other compounds presently under study for treatment of Alzheimer's disease. We studied the effect of this compound on acetylcholine (ACh), norepinephrine (NE), dopamine (DA) and serotonin (5-HT; 5-hydroxytryptamine) by means of transcortical microdialysis in the cortex of awake rats with no ChEI in the probe. We also compared the inhibition of brain cholinesterase (ChE) by two different approaches. Following 0.5 and 2.0 mg/kg s.c. administration, the increase in ACh was 200% (30 min) and 2100% (1 hr), respectively. The maximal ChE inhibition at 30 min was 35.5% (2.0 mg/kg) and 15.6% (0.5 mg/kg) when measured as ACh hydrolysis in the diluted homogenate. After the 2.0 mg/kg dose, phosphorylation by DFP was completely blocked at 30 min. After 0.5 mg/kg, ChE phosphorylation was maximally inhibited at 30 min (56%) and declined thereafter to negligible levels by 3 hr. In addition, E2020 increased extracellular levels of catecholamines in cortex in agreement with our previous findings with carbamate ChEI. Following 2.0 mg/kg, both NE (100%) and DA (80%) were elevated, whereas after 0.5 mg/kg only NE (50%) was affected. Neither dose affected extracellular 5-HT. Thus, E2020, which inhibits brain ChE by a novel, reversible mechanism, elevates extracellular ACh in a comparable manner to other centrally-active ChEI, and this elevation of ACh is associated with stimulation of catecholamine release.

Acetylcholine↗
PubMed1996

Arthrogryposis multiplex congenita in a monozygotic twin. An intrauterine lesion?

Arthrogryposis multiplex congenita is a specific, well-defined congenital deformity which primarily affects muscles of limbs resulting in secondary joint deformities. The aetiology is still uncertain. One of monozygotic twin brothers with classical arthrogryposis multiplex congenita is presented, proving that this specific condition is not genetically transmitted.

Arthrogryposis↗
PubMed1996

Hyperactivity and delay aversion. III: The effect on cognitive style of imposing delay after errors.

The claim that impulsiveness associated with hyperactivity is the result of deficits in inhibition of responses over time was examined. The cognitive style of hyperactive children was studied under two conditions. As in previous studies hyperactive children appeared impulsive (i.e. gave shorter latencies and made more errors than controls) under conditions where this style led to shorter trials. In contrast, in a revised condition where each error led to an enforced/fixed trial length, hyperactive children waited as long as controls before responding, but still made more errors. Hyperactive children withheld responses when this offered them the best chance of avoiding extra delay. They were however, unable to use the extra time provided as effectively as controls. The link between hyperactive children's aversion to delay and their poor use of time is discussed.

Child↗
PubMed1996

Seasonal-, tidal-cycle- and microhabitat-related variation in membrane order of phospholipid vesicles from gills of the intertidal mussel Mytilus californianus

Alterations in the order, or fluidity, of cellular membranes in response to variations in environmental temperature are well known. The mussel Mytilus californianus, a common inhabitant of mid-intertidal regions along the Pacific coast of North America, can experience large (20 &deg;C or more) and cyclic (every 6 h) changes in body temperature (Tb ) during tidal cycles. In the present study, we explore membrane order during seasonal and tidal temperature cycles and find that vesicles prepared from gill phospholipids exhibit significant seasonal differences in order that are consistent with homeoviscous adaptation and suggest winter-acclimatization to mean Tb values and summer-acclimatization to upper extreme Tb values or to large cyclic thermal fluctuations, despite repeated resubmergence in sea water at 10 &deg;C during both seasons. Phospholipid vesicles prepared from the gills of mussels acclimated for 6 weeks to constant high or low temperatures in the laboratory fail to exhibit temperature-compensatory differences in order. In addition, during the summer, mussels inhabiting high intertidal sites, but not those from low sites, possess the ability to alter membrane order rapidly (within hours). This alteration of order appears to represent a mechanism designed to offset the thermal variations encountered during the tidal cycle. Thus, M. californianus have the ability to adjust membrane order on seasonal as well as hourly time scales and do so on the basis of their height in the intertidal region.

Journal Article↗
PubMed1996

Clinical and laboratory features of adult T-cell leukaemia lymphoma in Barbados.

We describe the clinical and pathological features of 23 Afro-Caribbean patients with adult T-cell leukaemia/lymphoma admitted to the Queen Elizabeth Hospital, Barbados over a 5 year period. There were 9 males and 14 females, with a median age of 38 years (range 14-84). Twelve had acute leukaemia, 10 lymphoma (including 4 with solitary extra nodal lesions) and 1 smouldering subtype. Two patients had a past history of tropical spastic paraparesis/HTLV I associated myelopathy (TSP/HAM). The prognosis was poor, with only 3 complete responses to chemotherapy (CHOP) lasting from 9 to 36 months. We conclude that ATLL in Barbados is similar to the disease in the other Caribbean islands and Japan, except that in Barbados the age of onset is over a decade younger than in Japan.

Adolescent↗
PubMed1996

Mammary hamartoma--an under-recognised breast lesion.

The clinical, histological and immunohistochemical features of the first three cases of mammary hamartoma diagnosed at the University Hospital of the West Indies are reported. These tumours are innocuous and under-recognized although the mammographic features are characteristic. With increased utilization of this test in breast cancer detection in our region, it is likely that more of these lesions will be identified.

Adenofibroma↗