PubMed Health⌕ Search

Biomedical subjects

M Weston

Publications and source records attributed to M Weston.

At least 19 recordsLinked to original sources

The effect of match standard and referee experience on the objective and subjective match workload of English Premier League referees.

The aim of the present study was to examine the effect of match standard and referee experience on the objective and subjective workload of referees during English Premier League and Football League soccer matches. We also examined the relationship between heart rate (HR) and ratings of perceived exertion (RPE) for assessing match intensity in soccer referees. Heart rate responses were recorded using short-range telemetry and RPE scores were collected using a 10-point scale. Analysis revealed a significant relationship between mean match HR and match RPE scores (r=0.485, p<0.05, n=18). There were significant differences in match HR (Premier League 83.6+/-2.6% maximal HR (HRmax) versus Football League 81.5+/-2.2%HRmax, p<0.05) and match RPE scores (Premier League 7.8+/-0.8 versus Football League 6.9+/-0.8, p<0.05) between standards of competition. Referee experience had no effect on match HR and RPE responses to Premier League and Football League matches. The results of the present study demonstrate the validity of using HR and RPE as a measure of global match intensity in soccer referees. Referee experience had no effect on the referees' objective and subjective match workload assessments, whereas match intensity was correlated to competition standard. These findings have implications for fitness preparation and evaluation in soccer referees. When progressing to a higher level of competition, referees should ensure that appropriate levels of fitness are developed in order to enable them to cope with an increase in physical match demands.

Adult↗

Premature atherosclerosis in primary antiphospholipid syndrome: preliminary data.

OBJECTIVE: To investigate the atherosclerosis hypothesis in primary antiphospholipid syndrome (PAPS). METHODS: The intima media thickness (IMT) of carotid arteries and other cardiovascular risk factors was measured in 20 patients with PAPS (mean (SD) age 35 (12) years) and in 20 controls matched for age and sex (34 (12) years). RESULTS: The frequency of smoking, hypertension, and dyslipidaemia was similar in the two groups, but plasma homocysteine was higher in patients with PAPS (mean (SD) 11.9 (6.2) v 8.2 (3.4) micromol/l, p = 0.037). The IMT was slightly greater in patients with PAPS than in controls at the carotid bifurcation (mean (SD) 0.61 (0.24) v 0.48 (0.09) mm, p = 0.04) and internal carotid artery (0.52 (0.22) v 0.40 (0.08), p = 0.01). These differences were more evident in patients aged >40 years than in those aged <30 years at the carotid bifurcation (0.76 (0.25) v 0.55 (0.06), p = 0.0007) and internal carotid artery (0.63 (0.25) v 0.45 (0.09), p = 0.02); no differences were seen in the younger age group compared with controls. CONCLUSION: Atherosclerosis is a possibility in patients with PAPS in their fourth decade of life or older.

Adult↗

Evolving trends in risk profiles and causes of death after heart transplantation: a ten-year multi-institutional study.

BACKGROUND: As therapeutic options evolve for advanced heart failure, the appropriate role for cardiac transplantation will require survival analyses that reflect changing trends in causes of death and patient and institutional risk profiles. Results from multi-institutional studies could be used to monitor progress in individual centers. METHODS: Between 1990 and 1999, 7290 patients undergoing cardiac transplantation in 42 institutions entered a formal outcomes study. Changing survival, causes of death, and patient risk profiles were analyzed. Multivariable risk-factor equations were applied to a single institution (300 primary heart transplants) to examine differences in risk-adjusted expected versus observed actuarial outcomes over time. RESULTS: Overall survival in the 42 institutions improved during the decade (P =.02). One- and 3-year cardiac transplant research database survival was as follows: era 1 (1990-1992), 84% and 76%, respectively; era 2 (1993-1995), 85% and 79%, respectively; and era 3 (1996-1999), 85% and 79%, respectively. Causes of death changed over time. Pretransplantation risk profiles increased over time (P =.0001), with increases in reoperations, devices, diabetes, severely ill recipients, pulmonary vascular resistance, sensitization, ischemic times, donor age, and donor inotropic support. Three-year actuarial survival in a single institution was 3% less than risk-adjusted predicted survival in era 1, 1% higher than predicted in era 2, and 7% higher than predicted in era 3. CONCLUSIONS: Survival after cardiac transplantation is gradually improving, despite increasing risk profiles. Further improvement requires periodic re-evaluation of risk profiles and causes of death to target areas of surveillance, therapy, and research. By using these methods, progress at individual institutions can be assessed in a time-related, risk-adjusted manner that also reflects changing institutional experience, expertise, or both.

Cause of Death↗

Duplication of the vertebral artery: report of two cases and review of the literature.

Duplication of the vertebral artery is rare. We report two cases in which it was an incidental finding. In the first, duplication of the right vertebral artery was demonstrated by magnetic resonance angiography (MRA) and conventional angiography. The second patient had duplication of the right vertebral artery demonstrated by MRA. We discuss the origin of this abnormality, its radiological implications and its potential clinical significance are discussed.

Aged↗

Venesection needle coring increases positive results with RT-PCR for detection of circulating cells expressing CEA mRNA.

We assessed whether circulating cell positivity using RT-PCR for carcinoembryonic antigen (CEA) cDNA was affected by venesection via a needle compared with a pre-aspirated venous cannula, and by increased PCR cycles. Systemic blood was sampled by needle and pre-aspirated cannula in 101 healthy individuals with no cancer history. After erythrocyte removal, samples were subjected to RT-PCR using specific primers for CEA, with 29 or 35 RT-PCR cycles. There was a significant difference between the number of subjects whose samples were negative when collected via needle venesection and positive when collected via pre-aspirated cannula, compared with positive by needle venesection and negative by pre-aspirated cannula for both 29 (P = 0.016) and 35 (P = 0.0111) RT-PCR cycles. Venesection technique (P = 0.01) and number of cycles (P = 0.003) were significant predictors of a positive result. Positive results in healthy subjects were reduced to less than 3% when an aspirated cannula was used for venesection and >29 PCR cycles were avoided.

Adult↗

Conserved residues amino-terminal of cytoplasmic tyrosines contribute to the SHP-1-mediated inhibitory function of killer cell Ig-like receptors.

The sequence I/VxYxxL, often referred to as an immunoreceptor tyrosine-based inhibition motif (ITIM), binds to the C-terminal Src homology 2 domain of the tyrosine phosphatase SHP-1. Conserved residues N-terminal of the tyrosine are not ordinarily found in other Src homology 2 domain binding motifs. The inhibitory forms of killer cell Ig-like receptors (KIR) contain two ITIMs. The role of each ITIM, and of the conserved residues upstream of the tyrosine, in the inhibition of NK cells was tested by vaccinia virus-mediated expression of mutant KIRs. Substitution of the tyrosine in the membrane-proximal ITIM abrogated the ability of KIR to block Ab-dependent cellular cytotoxicity, whereas mutation of the membrane-distal ITIM tyrosine had little effect. Substitution of the conserved hydrophobic amino acid that was located two residues N-terminal to the tyrosine weakened, but did not eliminate, the function of the receptor. In contrast, these substitutions drastically reduced the amount of SHP-1 immunoprecipitated with KIR, suggesting that weak interactions with SHP-1 may be sufficient for inhibition.

Amino Acid Sequence↗

Up-training loading responses in older adults.

This randomized, experimental-control group, multiple-observation study examined the ability of older adults to use center of pressure feedback to up-train the vertical loading response (LR) and the impact that such training had on changes in clinical tests of balance. Eleven community ambulators, aged at least 65 years, with no recent history of falls were recruited by convenience sampling. Each group received 6 baseline sessions and 6 control/training sessions, followed by 1 posttest session. All sessions included visual cueing about stance equilibrium followed by 30 randomly timed dynamic, toes-up perturbations (8 degrees, 66 degrees per second). Training consisted of verbal instructions with visual and auditory feedback of a 225 msec response window to shape an increase in total LR following perturbations. Subjects in the experimental group demonstrated a tendency to decrease vertical loading relative to baseline regardless of visual and verbal feedback encouraging strategies to increase it. Specifically, the T3 or 150-225 msec component of the response window showed a decline from session 7 to session 12. Up-training, however, appears to cause a faster rate of rise to the maintenance window, but this event probably occurs too late to correct for a loss of balance. No correlation was found between change in load values and change in performance on clinical balance tests.

Accidental Falls↗

Prenatal diagnosis of an extensive fetal lymphangioma using ultrasonography, magnetic resonance imaging and cytology.

An unusual case of fetal lymphangioma diagnosed before delivery is reported in a second trimester pregnant woman. The lymphangioma was suspected at 28 weeks on the basis of the ultrasound appearances and progression of the lesions with advancing gestation. MRI was used to evaluate the extent and the tissue characteristics of the lesions. Cytology of the fluid aspirated from the cystic lesions showed abundant lymphocytes and macrophages, confirming the diagnosis of a lymphangioma. The parents opted for a pregnancy termination because of the rapid growth of the lesions and the poor prognosis. It is suggested that the combination of these tests could enable the early diagnosis of these tumours at a stage when the lesion is relatively limited and accessible to therapy in utero.

Adult↗

Case report: The "veiled right kidney sign"--an ultrasound finding in retroperitoneal perforation of the duodenum.

We report a case of traumatic duodenal perforation where the diagnosis was first considered during abdominal ultrasound examination. A subsequent CT scan identified the site of perforation which was confirmed at laparotomy. This condition typically produces few clinical signs or symptoms initially but has a high mortality related to delayed diagnosis. The ultrasound findings that prompted early diagnosis are described.

Adult↗

Lessons learned from Hurricane Andrew: recommendations for care of the elderly in long-term care facilities.

We report on the experience of a 500-bed, long-term care facility in Miami, Fla, which provides housing and nursing care units for patients--ranging from those who are independently ambulatory to those who are acutely ill and feeble--in preparing for, during, and in the immediate aftermath of Hurricane Andrew, which struck on August 24, 1992. The problems encountered included a massive influx of evacuated elderly to the facility, facility isolation, loss of electrical power, loss of running water, special dietary needs, and limited professional staffing due to personal property losses or loss of transportation. Overwhelmed county emergency medical services, limited access to hospitals and patient care, and difficulty in procuring supplies exacerbated the already complicated situation resulting from the storm. As a result of these catastrophic conditions, a number of challenges specific to the care of the elderly were identified. In conjunction with the Florida Department of Elder Affairs, we drafted a comprehensive blueprint that could serve as a disaster plan for other long-term care facilities facing a similar threat during the hurricane season.

Aged↗

Randomised trial of coronary intervention with antibody against platelet IIb/IIIa integrin for reduction of clinical restenosis: results at six months. The EPIC Investigators.

Restenosis after coronary angioplasty occurs in at least 30% of patients in the first six months and, as yet, there is no known treatment to decrease this event. We tested a monoclonal antibody Fab fragment (c7E3) directed against the platelet glycoprotein IIb/IIIa integrin, the receptor mediating the final common pathway of platelet aggregation, to see whether it reduced the frequency of clinical restenosis. Patients who had unstable angina, recent or evolving myocardial infarction, or high-risk angiographic morphology, were randomised to receive c7E3 bolus and a 12 hour infusion of c7E3 (708 patients), c7E3 bolus and placebo infusion (695 patients), or placebo bolus and placebo infusion (696 patients). With maintenance of the double-blind state, patients were followed-up for at least 6 months to determine the need for repeat angioplasty or surgical coronary revascularisation and the occurrence of ischaemic events. By 30 days, 12.8% of placebo bolus/placebo infusion patients had had a major ischaemic event (death, myocardial infarction, urgent revascularisation), compared with 8.3% of c7E3 bolus/c7E3 infusion patients, yielding a 4.5% difference (35% reduction, p = 0.008). At 6 months, the absolute difference in patients with major ischaemic event or elective revascularisation was 8.1% between placebo bolus/placebo infusion and c7E3 bolus/c7E3 infusion patients (35.1% vs 27.0%; 23% reduction p = 0.001). The favourable long-term effect was mainly due to less need for bypass surgery or repeat angioplasty in patients with an initial successful procedure, since need for repeat target vessel revascularisation was 26% less for c7E3 bolus/c7E3 infusion than for placebo treatment (16.5% vs 22.3%; p = 0.007). The c7E3 bolus/placebo infusion group had an intermediate outcome which was not significantly better than that of the placebo bolus/placebo infusion group. These results extend the benefit of c7E3 bolus/c7E3 infusion from reducing abrupt closure and acute-phase adverse outcomes to a diminished need for subsequent coronary revascularisation procedures. Because this therapy carries a risk of bleeding complications and has been studied only in high-risk angioplasty patients, further evaluation is needed before it can be applied to other patient groups.

Angioplasty, Balloon, Coronary↗

Effects of pediatric HIV infection and prenatal drug exposure on mental and psychomotor development.

Examined the effects of HIV infection and prenatal drug exposure on infant neurodevelopmental functioning. Three groups of infants were compared: HIV-infected infants, seroreverters, and a comparison group who were prenatally exposed to drugs, but not HIV. Two thirds of the HIV-infected and seroreverter infants were prenatally drug-exposed. Infants (ages 4-30 months) were administered the Bayley Scales of Infant Development. Children who were both HIV-infected and prenatally drug exposed performed significantly lower on both the mental and psychomotor scales of the Bayley. Drug exposure and neurological dysfunction were associated with mental development, whereas neurological dysfunction, drug exposure, and HIV status were associated with psychomotor development.

Child Development↗

Avascular necrosis of bone following intensified steroid therapy for acute lymphoblastic leukaemia and high-grade malignant lymphoma.

Five out of nine adults (55%) with lymphoblastic disease developed severe avascular necrosis of bone (AVN) when treated with a Berlin-Frankfurt-Munster (BFM) ALL protocol similar to the current joint MRC-ECOG ALL trial (UKALL XII). The principal purpose of these intensified regimens is to improve long-term disease-free survival without necessarily increasing toxicity and secondary morbidity. The presentation of all five was non-specific bone pain occurring after the re-intensification block of chemotherapy containing high doses of dexamethasone. Three types of diagnostic imaging were performed and magnetic resonance imaging (MRI) proved superior in demonstrating AVN and showed it at an earlier stage than plain radiographs or isotopic scans. We believe that the dose of corticosteroids was the major factor in the development of AVN. The five men in our series all remain in first remission with a median disease-free survival of 3.5 years (range 2-8 years) but with varying degrees of disability due to AVN. Clinicians involved in UKALL XII and similar trials should be aware of this debilitating and potentially crippling complication when using high-dose steroid-containing regimens, perform MRI scan early and modify treatment if necessary.

Adolescent↗

Changes in local blood volume during cold gel pack application to traumatized ankles.

Whether application of a cold modality following soft tissue trauma causes reactive vasodilation causes reactive vasodilation is an important clinical question since one goal of using a cold modality is to limit edema formation. The purpose of this study was to measure change in local blood volume during application of a cold gel pack following inversion sprain of the ankle. Fifteen volunteers participated as subjects (age range: 18-46 years, mean age: 22.2 years). A bilateral tetrapolar impedance plethysmograph was used with venous occlusion to measure the change in local limb volume at the ankle over a 20-minute period during two conditions: at rest and with cold gel pack application. A significant reduction in local blood volume occurred during cold gel pack application compared with rest. A significant vasodilation response was not observed. The lack of vasodilation response lends support to the clinical use of a cold gel pack following soft tissue trauma when applied to the ankle for a period of up to 20 minutes.

Adolescent↗