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C Wharton

Publications and source records attributed to C Wharton.

11 recordsLinked to original sources
PubMed2005

Encasement of bedding does not improve asthma in atopic adult asthmatics.

AIM: We evaluated the impact of impermeable bed covers on asthma in asthmatics with clinically relevant house dust mite (HDM) sensitization. METHODS: The study included 32 HDM-sensitized asthmatics in whom HDM allergy was considered as a significant factor in their asthma. They were randomized into either an intervention group whose bedding was encased with impermeable covers, or a control group who received cotton covers. Before and 3 and 6 months after encasement, dust samples were collected from the bedding and assayed for Der p 1. Clinical outcomes included quality of life, lung function, bronchial reactivity to methacholine, symptoms, medications and peak flow rates. RESULTS: Baseline Der p 1 levels in both the active and the placebo groups were comparable and high (19.2 vs 18.9 microg/g of dust). There was a significant reduction in Der p 1 levels in the active group after 6 months, but not in the placebo group (7.3 vs 21.9 microg/g of dust). Quality of life improved significantly in both the intervention and control groups, but there was no significant difference in the improvements between the groups. There was no significant change in lung function, symptoms, and requirements for medications. CONCLUSIONS: Encasement of bedding significantly reduced the Der p 1 levels. However, this was not sufficient to produce worthwhile clinical improvement in those in whom dust mite avoidance might well have been recommended as part of their clinical management.

Adult↗
PubMed2001

The rising prevalence of asthma in young Melbourne adults is associated with improvement in treatment.

BACKGROUND: Asthma is a common source of morbidity and is now recognized as a national health priority in Australia. Although a number of epidemiologic studies have been conducted in Australia to determine the prevalence of asthma in adults, it is unclear whether the prevalence is changing. OBJECTIVES: To determine the prevalence in 1998 of self-reported asthma and respiratory symptoms among young adults and changes in prevalence between 1990 and 1999. METHODS: Cross-sectional postal survey to 4,455 young adults (aged 20 to 44 years) randomly selected from the electoral rolls of the inner southeastern suburbs of metropolitan Melbourne. The survey instrument was the validated European Community Respiratory Health Survey screening questionnaire, which gathered data on self-reported respiratory symptoms, including whether asthma had been diagnosed. Identically worded questions from similar surveys conducted in 1990, 1992, and 1999 were used to compare changes in prevalence. RESULTS: A response rate of 72% was achieved in 1998 after three mailings and telephone followup. Forty-two percent reported nasal allergies, 26% wheezed within the past 12 months, and 20% ever had asthma. The prevalence of doctor-diagnosed asthma was 18%, whereas 10% reported using asthma medications within the past 12 months. Nine percent of respondents reported an asthma attack within the past 12 months. The prevalence of having ever had asthma, doctor-diagnosed asthma, and using asthma medications had increased significantly since 1990. However, the prevalence of respiratory symptoms did not significantly change over this time. CONCLUSIONS: The prevalence of asthma is likely to be rising, but the symptoms of asthma are being better managed in young Melbourne adults.

Adult↗
PubMed2000

The calculating brain: an fMRI study.

To explore brain areas involved in basic numerical computation, functional magnetic imaging (fMRI) scanning was performed on college students during performance of three tasks; simple arithmetic, numerical magnitude judgment, and a perceptual-motor control task. For the arithmetic relative to the other tasks, results for all eight subjects revealed bilateral activation in Brodmann's area 44, in dorsolateral prefrontal cortex (areas 9 and 10), in inferior and superior parietal areas, and in lingual and fusiform gyri. Activation was stronger on the left for all subjects, but only at Brodmann's area 44 and the parietal cortices. No activation was observed in the arithmetic task in several other areas previously implicated for arithmetic, including the angular and supramarginal gyri and the basal ganglia. In fact, angular and supramarginal gyri were significantly deactivated by the verification task relative to both the magnitude judgment and control tasks for every subject. Areas activated by the magnitude task relative to the control were more variable, but in five subjects included bilateral inferior parietal cortex. These results confirm some existing hypotheses regarding the neural basis of numerical processes, invite revision of others, and suggest productive lines for future investigation.

Adult↗
PubMed2000

Asthma is more prevalent in rural New South Wales than metropolitan Victoria, Australia.

OBJECTIVE: The aim of this study was to compare the prevalence of adult respiratory symptoms and conditions in a rural setting with a metropolitan setting. METHODOLOGY: We used cross-sectional population surveys of respiratory health using the European Respiratory Health Survey screening questionnaire. A random sample of 4455 eligible young adults aged 20-44 years, from electoral rolls in south-eastern metropolitan Melbourne, Victoria, and 4521 from rural south-western New South Wales were surveyed. RESULTS: Response rates of 72% (n=3194) and 69% (n=3121) were achieved in Melbourne and the Riverina, respectively. Respondents from the Riverina reported significantly higher prevalences of nocturnal dyspnoea (P<0.01), chronic bronchitis (P=0.03), an asthma attack in the previous 12 months (P<0.001), ever having had asthma (P<0.001) and doctor-diagnosed asthma (P<0.001) compared to those from Melbourne. However, among those with 'asthma attacks in the last 12 months', Melbourne respondents experienced a higher frequency of attacks (P<0.05). Riverina respondents reported a higher prevalence of smoking (P<0.05) and smoked more cigarettes on average (P<0.001) than Melbourne respondents. However, annoyance from air pollution was higher in Melbourne than in the Riverina. CONCLUSIONS: These results suggest that asthma is more prevalent in rural southern New South Wales than in Melbourne but follows a different pattern of exacerbations.

Adult↗
PubMed1984

Conformational changes and loss of opsonic function in frozen or heat-treated plasma fibronectin.

Using human peripheral blood monocytes to assay opsonic protein activity, we have examined the efficiency of various procedures for isolating fibronectin from plasma for experimental or therapeutic use. In addition, we have assessed the protein's opsonic activity after cold storage, and after heat treatment to inactivate hepatitis virus. The purification procedures recovered only 30% of available plasma fibronectin whilst cold storage and heat treatment of the purified protein removed all of its remaining opsonic activity. This was associated with no alteration in overall molecular weight or in subunit size but was accompanied by changes in ultraviolet spectrum, suggesting a conformational change in the protein structure. Initial experiments to protect the purified protein against these changes were unsuccessful and unless further attempts are more encouraging, fresh-frozen plasma may be the only current economic source of opsonically active fibronectin. Since this would waste other valuable proteins required for other purposes, the widespread use of plasma fibronectin outside of clinical trials may be unjustified at this present time.

Chromatography, Affinity↗
PubMed1978

Niemann-Pick disease: prenatal diagnoses and studies of sphingomyelinase activities.

Five pregnancies were monitored for couples at-risk for having a child with some form of Niemann-Pick disease (NPD). Three of these were for the classic Type A form in which affected children usually have less than 1% of normal sphingomyelinase activity. Two of these pregnancies were terminated after the cultured amniotic-fluid cells were determined to have less than 1% of normal sphingomyelinase activity (0.4 and 0.6 nmole/mg protein/hr versus the control mean of 61.7). In the other pregnancy at risk for Type A NPD near normal activity was measured and it was continued to term. The two other pregnancies were monitored for couples in which severely affected children were found to have partially deficient sphingomyelinase activity (about 20% of normal) in cultured skin fibroblasts. Cultural amniotic-fluid cells from one of these pregnancies also had about 20% of control sphingomyelinase activity, but the woman underwent a spontaneous abortion soon after the cells were received and no studies on the fetus were done. The other sample was taken at the time of abortion for social reasons. In this case the cultured amniotic-fluid cells and cultured fetal skin fibroblasts gave normal sphingomyelinase activity. Enzymatic studies on tissues from the two fetuses predicted to be affected with Type A NPD confirmed the prenatal diagnosis. Studies of sphingomyelinase activity in the brains from these fetuses and from a child who died with Type A NPD indicated significant levels of activity when measured at pH 7.4 in the presence of magnesium. The higher level of the pH 7.4 sphingomyelinase activity in developing brain may indicate some important role in normal brain development.

Adult↗
PubMed1978

Synthetic substrate beta-glucosidase activity in leukocytes: a reproducible method for the identification of patients and carriers of Gaucher's disease.

A method is described for the identification of patients and carriers of Gaucher's disease, using leukocytes from a small volume of blood. The fluorogenic substrate, 4-methylumbelliferyl-beta-D-glucopyranoside, was assayed in the presence of pure sodium taurocholate (2.5 mg/ml) and Triton X-100 (2.0 mg/ml). Some commercial brands of pure sodium taurocholate were satisfactory for this purpose. The pH optimum for controls, Gaucher disease carriers and Gaucher disease patients was 5.4 using citrate-phosphate buffer. Although leukocytes prepared from only a small amount of blood (2-8 ml) are required, there is sufficient quantity for measuring other lysosomal enzymes as controls. Using this method, 12 patients with all types of Gaucher's disease and 12 obligate heterozygotes were identified. Carrier status was predicted in six other family members and ruled out in six others. Eight unaffected people married to Gaucher carriers or Gaucher patients were predicted to be non-carriers of Gaucher's disease, thereby ruling out children affected with Gaucher's disease in that mating.

Adult↗