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S Hill

Publications and source records attributed to S Hill.

At least 19 recordsLinked to original sources
PubMed2006

Transient left ventricular dysfunction with apical ballooning (tako-tsubo cardiomyopathy) in Germany.

AIMS: A peculiar type of an acute coronary syndrome is characterised by acute onset of chest pain, STsegment changes, elevated troponin I levels and a transient balloon-like apical left ventricular dysfunction, but without significant coronary artery disease. We sought to assess this syndrome in German patients. METHODS AND RESULTS: A total of 22 females and 1 male with acute transient left ventricular dysfunction were identified during an interval of 2 years and were investigated clinically and angiographically. All patients presented without obstructive coronary artery disease. In 16 patients (70%) ST-segment elevations were observed mimicking acute myocardial infarction, whereas the remaining patients (30%) revealed only negative T waves. Deep negative Twaves were characteristically seen during the course of recovery in all patients. Elevated troponin I levels>2.0 microg/l (upper level of normal) were measured in all patients (mean 18+/-26.5 microg/l, range from 2.2-135.7 microg/l). Creatine kinase rose up to a mean of 282+/-236 IU/l (upper level of normal 180 U/l). Emotional or physical stress situations associated with the onset of the symptoms were observed in 16 patients (70%). Other suspected trigger factors were gastrointestinal infection and in one case a surgical intervention. In four patients a trigger factor could not be identified. Left ventriculography showed an ejection fraction of 53+/-15%. After an interval of 7+/-2 days after the first angiogram, ejection fraction had increased from 48+/-11% to 64+/-11% in eight controlled patients by repeated ventriculography. Coronary spasm with a lumen reduction>75% could be provoked using acetylcholine in 10 of 17 tested patients (59%) with reproduction of the symptoms. Within 14 days the LV dysfunction returned to normal in all patients. The ECG abnormalities disappeared completely as early as 3 months (74%) and were not seen in any patient after 6 months. CONCLUSION: Tako-tsubo cardiomyopathy is not exclusively a Japanese or Northern American phenomenon. Despite increased patient reports the exact underlying cause and pathophysiology of this syndrome remain unclear. However, despite the initial dramatic presentation of this disease the prognosis is good.

Aged↗
PubMed2005

Impairment of lung function, health status and functional capacity in patients with ANCA-associated vasculitis.

OBJECTIVE: To determine the effects of lung involvement on respiratory function in patients with ANCA-associated vasculitis and the relation to impaired health status. METHODS: Thirty patients with ANCA-associated vasculitis in remission (15 with lung involvement at diagnosis as determined by an abnormal chest X-ray) were examined. We measured lung function, skeletal muscle strength [quadriceps force (QF), respiratory muscle strength (Pi(max))], exercise capacity (VO(2) peak) using treadmill exercise tests, and health status using the Short Form 36 and St George's respiratory questionnaires. RESULTS: Exercise capacity was reduced compared with predicted values (58.2%, range 23-123%) and 18 patients showed functional aerobic impairment. Respiratory muscle function was reduced (72.1% predicted, range 20-108%) and was not related to lung involvement or steroid usage. Transfer factor correlated significantly with exercise capacity, suggesting inadequate delivery of oxygen to muscles. Nine patients had reduced transfer factor (seven with lung involvement). Patients with lung involvement had impaired gas transfer compared with those without lung involvement (96.9 +/- 6 vs 113.3 +/- 4.7% predicted, P = 0.04). However, there were significant abnormalities in other lung function parameters not related to previous lung involvement (eight patients had reduced forced expiratory volume in 1 s, and five patients had reduced residual volume). Twelve patients (five with previous lung involvement) had obstructive airways disease. Physical health status was impaired to a greater degree than mental health status across the whole group and was not related to lung involvement or original disease severity, but correlated with transfer factor. CONCLUSION: Patients with ANCA-associated disease may have significant lung function impairment irrespective of lung involvement at the time of diagnosis. Patients showed reduced respiratory muscle strength, health status and exercise capacity, which correlated with reduced transfer factor.

Adult↗
PubMed2005

Lipid metabolism in young men after acute resistance exercise at two different intensities.

The aim of this study was to examine the effects of different resistance training loads on blood lipids. Six healthy, untrained male volunteers performed three protocols: control (no exercise), high intensity (HI) and low intensity (LI) exercise seven days apart. Each protocol comprised eight exercises. The HI protocol used a 10-repetition maximum (RM) load and 10 repetitions. In the LI protocol, the load was halved and repetitions doubled. The volume of work performed in the two exercise protocols was identical. Blood samples were collected before, immediately after, and 15 min after each protocol and analysed for total, high density (HDL-C), low density cholesterol and triglyceride. The only significant effect of exercise was to acutely increase HDL-C in the immediate post exercise sample compared with the control. There was no significant effect on any lipid fraction resulting from the LI protocol compared with the control. The results of this study suggest that intensity alone has an effect in determining the HDL-C response to acute resistance exercise.

Adult↗
PubMed2005

Cooperative partnerships or conflict-of-interest? A national survey of interaction between the pharmaceutical industry and medical organizations.

BACKGROUND: There is extensive and varied interaction between the pharmaceutical industry and the medical profession. Most empirical research concerns contact between individual physicians and industry, and reflects North American experience. We sought to clarify the extent and nature of relationships between the pharmaceutical industry and Australian medical organizations. METHODS: We administered questionnaires to 63 medical organizations concerned with clinical practice, continuing medical education or professional accreditation, or the political representation of medical professionals. RESULTS: Survey instruments were received from 29 organizations, giving a response rate of 46%. Seventeen of these organizations (59%) had received support from one or more pharmaceutical company in the past financial year. Support was predominantly for annual conferences, with some support for continuing medical education, research, travel and library purchases. The majority of organizations had an academic journal or newsletter, and 10 (34%) accepted revenue from pharmaceutical advertising. Twenty organizations (72%) had policies or guidelines covering their relationship with industry. Few organizations indicated that they would be unable to continue their activities without pharmaceutical industry support. CONCLUSION: These data indicate a high level of inter-action between the pharmaceutical industry and medical organizations in Australia. While most organizations have policies for guiding their relationship with industry, it is unclear whether these are effective in preventing conflicts of interest and maintaining public trust.

Australia↗
PubMed2005

Soy intake plus moderate weight resistance exercise: effects on serum concentrations of lipid peroxides in young adult women.

AIM: Exercise can conceivably increase concentrations of lipid peroxides (by producing oxidant stress) or decrease their concentrations (by accelerating peroxide breakdown). The net effect could depend on exercise intensity and nutritional antioxidant intake. METHODS: Recreationally trained, young adult women (n=18) consumed antioxidant-rich soy protein or antioxidant-poor whey protein for 4 weeks (40 g protein/day). A moderate intensity, weight resistance exercise session was done before and after the 4 week period. Blood was drawn before each exercise session and postexercise at 0, 3 and 24 h. Serum from the pre-exercise draw was analyzed for antioxidant status (based on radical scavenging capacities); serum from pre- and postexercise draws were analyzed for concentrations of lipid peroxides as well as creatine kinase activities (which are affected by oxidant damage to muscles). RESULTS: Soy, but not whey intake, increased pre-exercise serum antioxidant status values and inhibited exercise-induced increases in creatine kinase activities. Before soy or whey intake, serum values for lipid peroxides rose at two of the three postexercise times. After whey intake, values for lipid peroxides showed no increase at the three postexercise times. After soy treatment, values for lipid peroxides actually showed a decrease at the three postexercise times. CONCLUSIONS: Moderate intensity exercise exerted variable effects on serum lipid peroxides with decreases occurring with 4 weeks of soy intake, which also produced other antioxidant effects.

Adolescent↗
PubMed2005

Risk factors for defaulting from tuberculosis treatment: a prospective cohort study of 301 cases in the Gambia.

SETTING: An urban tuberculosis (TB) clinic, The Gambia. OBJECTIVE: To identify patient characteristics associated with increased rates of defaulting from treatment, specifically knowledge and cost factors amenable to intervention. DESIGN: Prospective cohort study of TB cases at least 15 years of age commencing treatment, interviewed by semi-structured questionnaire and followed for attendance at thrice-weekly directly observed treatment (DOT). RESULTS: Of 301 patients, 76 (25.2%) defaulted from treatment and 25 did not return for treatment. The defaulting rate was higher among those who said they were uncertain that their treatment would work (HR 3.64; 95%CI 1.42-9.31, P = 0.007) and among those who incurred significant time or money costs travelling to receive treatment (HR 2.67; 95%CI 1.05-6.81; P = 0.04). These factors had differing effects with respect to time: uncertainty over treatment success was important in the first 90 days of treatment, while increased cost of travelling to the clinic was important after 90 days. CONCLUSION: In The Gambia, risk groups for defaulting can be recognised at the start of treatment and are at highest risk at different times. Home-based self-administration of medications after 3 months of DOT should be considered as confidence in treatment success rises, and the costs of travelling to receive treatment start to take their toll.

Adolescent↗
PubMed2004

The development of a DNA microarray-based assay for the characterization of commercially formulated microbial products.

Commercially formulated bioproducts containing a complex consortia of bacteria as an active ingredient pose a significant challenge for regulatory agencies and companies seeking to assess the safety and efficacy of these bioproducts. The main challenge stems from how to characterize the bacterial composition of these products, for which there is presently a lack of suitable methods. A prototype DNA microarray composed of oligonucleotide probes for functional genes, virulence factors, and taxonomic genes for a number of bacterial species was developed to examine the utility of microarray technology as a molecular tool for characterizing consortia bioproducts. The genomic DNA from four different products was extracted by two methods and examined with the microarray prototype and by denaturing gradient gel electrophoresis (DGGE). Although the identity of the consortial species remains unknown, the microarray assay provided unique and reproducible hybridization patterns for all four products, and agreed with the fingerprints generated by DGGE. The ability to differentiate between a variety of consortia products demonstrates that DNA microarrays have the potential to be a powerful tool in monitoring complex microbial communities.

Bacteriological Techniques↗
PubMed2004

Weight and body composition changes during and after adjuvant chemotherapy in women with breast cancer.

Uncontrolled trials have reported significant weight gain in women with breast cancer during treatment with adjuvant chemotherapy. We prospectively evaluated body composition before (visit 1), immediately after (visit 2), and 6 months after (visit 3) chemotherapy in 20 women with stages I-IIIA breast cancer [body mass index (BMI): 24.1 +/- 3.9 kg/m(2)]. We compared their weight change to 51 age- and BMI-matched healthy controls (BMI: 25.5 +/- 3.8 kg/m(2)). In women with breast cancer, there was no weight change from visit 1-2, or from visit 1-3, but weight increased from visit 2-3 (+1.09 +/- 2.46 kg; P = 0.05). Weight change was not different from controls during either interval. In the breast cancer group, the percentage of body fat assessed by air displacement plethysmography increased, and fat-free mass decreased from visit 1-2 (+2.3 +/- 4% and -2.2 +/- 4%; P = 0.02) and from visit 1-3 (+4.0 +/- 6% and -3.8 +/- 6%; P = 0.01). By dual energy x-ray absorptiometry, the percentage of body fat increased from visit 2-3 (+0.9 +/- 1.6%; P = 0.02). Bone mineral content decreased from visit 2-3 (-0.02 +/- 0.04 kg; P = 0.02) and from visit 1-3 (-0.04 +/- 0.06 kg; P = 0.005). By computed tomography, the visceral adipose to sc adipose tissue ratio decreased from visit 1-3 (-0.02 +/- 0.05 ml; P = 0.02). We conclude that, compared with controls, women with breast cancer receiving modern adjuvant chemotherapy regimens show no significant changes in weight during the first year of their treatment. They do, however, appear to undergo unfavorable changes in body composition.

Absorptiometry, Photon↗
PubMed2003

Frequency of venous thromboembolism in low to moderate risk long distance air travellers: the New Zealand Air Traveller's Thrombosis (NZATT) study.

BACKGROUND: The frequency and role of risk factors for venous thromboembolism related to air travel is uncertain. We aimed to establish the frequency of this disorder in a group of long distance air travellers and to investigate the role of potential risk factors. METHODS: We designed a prospective study into which we recruited individuals aged between 18 and 70 years, travelling for 4 h or more by aircraft. D-dimer measurement was done before and after travel. Participants with a negative D-dimer (<500 ng/L) before travel were included in the study. Those who became D-dimer positive or developed high clinical probability symptoms during the 3 months after travel were investigated with bilateral compression ultrasonography and CT pulmonary angiography. Suspected clinical and thrombophilic risk factors, and use of prophylactic measures, were assessed. FINDINGS: 1000 individuals were recruited, with 878 meeting inclusion criteria and completing the study. All participants travelled at least 10 h, with a mean total duration of air travel of 39 h (SD 12.5). 112 patients underwent radiological assessment on return. Frequency of venous thromboembolism associated with travel was 1.0% (9/878, 95% CI 0.5-1.9), which included four cases of pulmonary embolism and five of deep venous thrombosis. Six patients with venous thromboembolism had pre-existing clinical risk factors, two had a recognised thrombophilic risk factor, two travelled exclusively in business class, five used aspirin, and four wore compression stockings. INTERPRETATION: Our results suggest an association between multiple long distance air flights and venous thromboembolism, even in individuals at low to moderate risk. The role of traditional risk factors and prophylactic measures in air travel-related venous thromboembolism needs further investigation.

Adolescent↗
PubMed2003

Angle-resolved mapping of the fermi velocity in a quasi-two-dimensional organic conductor.

We demonstrate a new method for determining the Fermi velocity in quasi-two-dimensional (Q2D) conductors. Application of a magnetic field parallel to the conducting layers results in periodic open orbit quasiparticle trajectories along the Q2D Fermi surface. Averaging of this motion over the Fermi surface leads to a resonance in the interlayer microwave conductivity. The resonance frequency is simply related to the extremal value of the Fermi velocity perpendicular to the applied field. Thus, angle dependent microwave studies enable a complete mapping of the in-plane Fermi velocity. We illustrate the applicability of this method for the highly 2D organic conductor kappa-(BEDT-TTF)2I3.

Journal Article↗
PubMed2003

Quantum coherence in an exchange-coupled dimer of single-molecule magnets.

A multi- high-frequency electron paramagnetic resonance method is used to probe the magnetic excitations of a dimer of single-molecule magnets. The measured spectra display well-resolved quantum transitions involving coherent superposition states of both molecules. The behavior may be understood in terms of an isotropic superexchange coupling between pairs of single-molecule magnets, in analogy with several recently proposed quantum devices based on artificially fabricated quantum dots or clusters. These findings highlight the potential utility of supramolecular chemistry in the design of future quantum devices based on molecular nanomagnets.

Journal Article↗
PubMed2003

Definitive spectroscopic determination of the transverse interactions responsible for the magnetic quantum tunneling in Mn(12)-acetate.

We present detailed angle-dependent single crystal electron paramagnetic resonance (EPR) data for field rotations in the hard plane of the S=10 single molecule magnet Mn(12)-acetate. A clear fourfold variation in the resonance positions may be attributed to an intrinsic fourth-order transverse anisotropy (O(4)/(4)). Meanwhile, a fourfold variation of the EPR line shapes confirms a recently proposed model wherein disorder associated with the acetic acid of crystallization induces a locally varying quadratic (rhombic) transverse anisotropy [O (2)/(2) identical with E(S (2)/(x)-S(2)/(y))]. These findings explain most aspects of the magnetic quantum tunneling observed in Mn(12)-acetate.

Journal Article↗
PubMed2003

A phase II study of carboplatin and vinorelbine in patients with poor prognosis small cell lung cancer.

AIM: The aim of this study was to evaluate the activity of the combination of carboplatin and vinorelbine in patients with poor prognosis small cell lung cancer (SCLC). Patients with good prognosis disease were included who were not medically fit to tolerate conventional chemotherapy. Activity was assessed primarily as response rate and secondarily in terms of toxicity, time to progression and survival. PATIENTS AND METHODS: Fifty-eight patients, 37 men and 21 women, with histologically or cytologically confirmed SCLC, who had bi-dimensionally measurable disease, with ECOG performance status > or = 2, with adequate haematological, hepatic and renal function received first-line chemotherapy with carboplatin (AUC x 5) day 1 and vinorelbine (30 mg/m2) days 1 and 8 of a 28-day cycle. Response was assessed after every two cycles of chemotherapy, with patients receiving a maximum of six cycles of treatment. RESULTS: The combination of carboplatin and vinorelbine is an active regimen in the treatment of SCLC, with an overall intention-to-treat response rate of 55% [95% confidence interval (CI): 42-68%] with six (10%) of patients having a complete response. Median time to progression was 18 weeks (95% CI: 15-21 weeks). Median overall survival was 26 weeks (95% CI: 21-31 weeks). Ten patients failed to complete two cycles of treatment, and were not evaluable for response for the following reasons: septic death (1 neutropaenic, 1 no myelotoxicity), non-toxic death (1 tumour eroded through the pulmonary artery, 1 ischaemic heart disease) ischaemic heart disease (1) and patient decision (5). There were a total of three toxic deaths all sepsis-complicating neutropaenia. Forty-four (76%) patients experienced grade 3 or 4 neutropaenia, six (11%) grade 3 or 4 thrombocytopaenia, 10 (13%) grade 3 lethargy, three (5%) grade 3 nausea and two (3%) grade 3 diarrhoea. CONCLUSIONS: The combination of carboplatin and vinorelbine is active against SCLC but the toxicity profile in this group of patients suggests that further evaluation is not appropriate.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2003

Use of pharmacoeconomics in prescribing research. Part 1: costs--moving beyond the acquisition price for drugs.

This paper addresses pharmacoeconomics in prescribing research and reflects the increasing use of techniques of economic evaluation to aid drug purchasing decisions in a variety of settings -- for national drug subsidization programmes, provincial purchasing plans, insurance programmes, and for hospital and area health authority formulary decisions. First, we focus on the cost component of an economic evaluation and discuss methodological issues that are relevant to all pharmacoeconomic analyses.

Cost Control↗