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Richard Ruffin

Publications and source records attributed to Richard Ruffin.

11 recordsLinked to original sources

Anti-inflammatory effects of zinc and alterations in zinc transporter mRNA in mouse models of allergic inflammation.

There is clinical evidence linking asthma with the trace element, zinc (Zn). Using a mouse model of allergic inflammation, we have previously shown that labile Zn decreases in inflamed airway epithelium (Truong-Tran AQ, Ruffin RE, Foster PS, Koskinen AM, Coyle P, Philcox JC, Rofe AM, Zalewski PD. Am J Respir Cell Mol Biol 27: 286-296, 2002). Moreover, mild nutritional Zn deficiency worsens lung function. Recently, a number of proteins belonging to the Solute Carrier Family 39 (ZIP) and Solute Carrier Family 30 (ZnT) have been identified that bind Zn and regulate Zn homeostasis. Mice were sensitized, and subsequently aerochallenged, with ovalbumin to induce acute and chronic airway inflammation. Mice received 0, 54, or 100 microg of Zn intraperitoneally. Tissues were analyzed for Zn content and histopathology. Inflammatory cells were counted in bronchoalveolar lavage fluid. Cytokine and Zn transporter mRNA levels were determined by cDNA gene array and/or real-time PCR. Zn supplementation decreased bronchoalveolar lavage fluid eosinophils by 40 and 80%, and lymphocytes by 55 and 66%, in the acute and chronic models, respectively. Alterations in Zn transporter expression were observed during acute inflammation, including increases in ZIP1 and ZIP14 and decreases in ZIP4 and ZnT4. Zn supplementation normalized ZIP1 and ZIP14, but it did not affect mRNA levels of cytokines or their receptors. Our results indicate that inflammation-induced alterations in Zn transporter gene expression are directed toward increasing Zn uptake. Increases in Zn uptake may be needed to counteract the local loss of Zn in the airway and to meet an increased demand for Zn-dependent proteins. The reduction of inflammatory cells by Zn in the airways provides support for Zn supplementation trials in human asthmatic individuals.

Animals↗

Use of a zinc fluorophore to measure labile pools of zinc in body fluids and cell-conditioned media.

Here we describe a rapid and sensitive zinquin-based fluorometric assay that enables one to monitor levels of labile Zn(II) in body fluids, buffers, and cell-conditioned culture media as well as changes in these pools in disease. Labile pools of Zn(II) are free or loosely bound pools and more tightly bound but zinquin-accessible pools in contrast to the fixed pools of Zn(II) within metalloproteins. In human plasma, mean labile Zn(II) was 8.1 microM (SEM 0.53; n = 81) and constituted about 70% of the total plasma Zn(II) and >90% of human plasma albumin Zn(II). Plasma labile Zn(II) was significantly depleted after 7 days of Zn(II) deprivation in mice, despite only small changes in body weight. Labile Zn(II) concentrations were also measured in the induced sputum plugs, saliva, and urine of normal adults and were 1.30 microM (SEM 0.27; n = 73), 0.11 microM (SEM 0.11; n = 6), and 0.23 microM (SEM 0.08; n = 8), respectively. Urinary labile Zn(II) concentration was significantly increased in some patients with type II diabetes mellitus (overall mean was 0.90 microM, SEM 0.30; n = 12). The technique may be particularly useful in assessing extracellular Zn(II) levels in diseases associated with altered Zn(II) homeostasis, identifying those subjects most in need of Zn(II) supplementation, and defining the optimum concentrations of available Zn(II) in buffers and culture media.

Animals↗

Assessment of an asthma quality of life scale using item-response theory.

OBJECTIVE: Health-related quality of life (HRQOL) scores produced by simply summing individual item values have been criticized for lacking linearity and for not being equally discriminating across the range of scores. Differences in summed scores may depend more on their starting point on the scale rather than actual differences in the underlying dimension of HRQOL, making it difficult to judge what a particular score means. We sought to examine the usefulness of an alternative method of scoring questionnaires, item-response theory (IRT), for the clinical interpretation of a modified version of the Marks Asthma Quality of Life Questionnaire (MAQLQ-M). METHODOLOGY: Using the MAQLQ-M, we surveyed 293 adults with moderate to severe asthma, managed at two university teaching hospitals in Adelaide, South Australia. Scores obtained by usual summative Likert-type scores were compared to estimates using the partial credit method of IRT. RESULTS: We found a non-linear relationship between raw, summative scores and the IRT estimates. The departure from linearity was marked for summative scores below 3.0 and above 5.0 (range 1.0-7.0), values that included half of the study patients. Summative scoring did not produce scores at the interval level of measurement. CONCLUSION: For an equivalent difference measured in the underlying dimension of actual HRQOL using IRT, traditional summated scores showed a much smaller difference in scores at both the lower and upper end of HRQOL, than at the mid-range of HRQOL. Caution should be used when interpreting HRQOL surveys scored in the usual summative manner. Advantages may be gained by using IRT as an alternative method of scoring HRQOL questionnaires.

Adolescent↗

Difficulties identifying and targeting COPD and population-attributable risk of smoking for COPD: a population study.

STUDY OBJECTIVES: Respiratory public health interventions depend on accurate identification of the target group, yet this may vary depending on the diagnostic criteria used. We therefore compared the relative performance of various international criteria in identifying COPD cases. The burden of COPD due to smoking can only be determined from population-attributable risk (PAR) studies. These studies, lacking in the COPD literature, are necessary research in support of public health initiatives for COPD. In this representative population study, we also assessed the PAR for current and ex-smokers. DESIGN: A representative biomedical population sample of 2,501 South Australians aged > or = 18 years (The Northwest Adelaide Health [Cohort] Study). COPD diagnosis and severity were determined according to various FEV1/FVC and FEV1 percentage of predicted criteria recommended by international respiratory authorities. Demographic, health behavior, and quality-of-life data were obtained by telephone interview and self-completed questionnaire. SETTING: Northwest Adelaide. MEASUREMENTS AND RESULTS: The PAR of smoking (smokers and ex-smokers) for COPD ranged from 51 to 70% depending on the diagnostic respiratory criteria used. COPD prevalence varied depending on the criteria used: American Thoracic Society, 5.4%; British Thoracic Society, 3.5%; European Respiratory Society (ERS), 5.0%; Global Initiative for Chronic Obstructive Lung Disease, 5.4%. There was also substantial disagreement in the cases identified. An alternative approach using ERS reference values one residual SD from the mean produced a COPD prevalence estimate of 6.9%, with improved level of agreement with the established respiratory criteria suggesting their potential as screening criteria. CONCLUSIONS: The COPD risks associated with smoking and ex-smoking history were quantifiable using PAR, but PAR also suggests other, yet unquantified, risks. Targeting COPD cases for public health interventions is difficult given the range of spirometry criteria and the associated high level of underdiagnosis.

Adult↗

Asthma symptoms associated with depression and lower quality of life: a population survey.

OBJECTIVE: To identify any association between asthma and depression and quality of life. DESIGN AND SETTING: A face-to-face Health Omnibus Survey of a random and representative sample of the South Australian population in August 1998. PARTICIPANTS: 3010 randomly selected participants aged 15 years and over. MAIN OUTCOME MEASURES: Prevalence of doctor-diagnosed asthma, and scores for depression (measured by PRIME-MD instrument) and quality of life (measured by SF-36) in affected participants. RESULTS: The prevalence of asthma was 9.9%. The prevalence of major depression was significantly higher for those who experienced dyspnoea, wakening at night with asthma, and morning symptoms of asthma. Quality-of-life scores were also lower for the same groups. CONCLUSIONS: Depression is a serious but potentially remediable comorbidity with asthma that may affect appropriate diagnosis and outcome.

Adult↗

Body mass index, waist hip ratio, and waist circumference: which measure to classify obesity?

OBJECTIVES: To determine the proportion of a representative population sample of adults in South Australia who have a body mass index (a measure of overall obesity) classified as normal or underweight, but who also have a waist circumference or waist hip ration (measures of central obesity) that indicates obesity. METHODS: A representative population sample of adults aged 18 years and over living in the north west region of Adelaide (n = 2523) were recruited to the study. Clinical measures of height, weight, waist and hip circumference were obtained and used to determine body mass index, waist hip ratio and waist circumference. RESULTS: Among women with a normal body mass index, 19.0% had a high waist circumference (> or = 80 cm) and 8.5% had a high waist hip ratio (> 0.85). Among males with a normal body mass index, 3.4% had a high waist circumference (> or = 95 cm) and 0.1% had a high waist hip ratio (> 1.0). CONCLUSIONS: Body mass index, waist hip ratio and waist circumference all have a role in the identification of those who are obese or overweight.

Adolescent↗

Sustained improvements in dyspnea and pulmonary function 3 to 5 years after lung volume reduction surgery.

OBJECTIVES: To determine long-term survival rates of patients who underwent lung volume reduction surgery (LVRS) for emphysema and the factors associated with longer survival, and to evaluate levels of perceived dyspnea and health-related quality of life (HRQL) after a follow-up period of 3 to 5.5 years. DESIGN: Retrospective observational study. SETTING: Academic medical center METHODS: Telephone and postal surveys were used to obtain patient dyspnea scores and HRQL scores. Hospital databases and state registries were searched to determine patient survival and pulmonary function. RESULTS: Of 54 patients undergoing LVRS, 29 patients (18 men and 11 women) were available for follow-up, which ranged from 36 to 66 months (mean +/- SE, 51 +/- 1.5 months). There was significant sustained improvement in modified Medical Research Council scores compared to pre-LVRS: 2.19 +/- 0.19 vs 2.88 +/- 0.14 (p = 0.0000). Eleven of 22 patients demonstrated an increase in all three Mahler baseline dyspnea index grades of at least one level. Baseline body mass index (BMI) and post-LVRS length of stay (LOS) were significantly associated with survival: survivor vs deceased baseline BMI, 24.2 +/- 0.6 vs 21.4 +/- 0.5 (p = 0.002), and post-LVRS LOS, 15.4 +/- 1.7 days vs 28.7 +/- 5.3 days (p = 0.015). Compared to pre-LVRS, 20 patients with mean follow-up time of 45 months demonstrated significant sustained improvements in FEV(1) percentage of predicted (31.4 +/- 2.1% vs 39.8 +/- 3.5%, p = 0.038), total lung capacity percentage of predicted (136 +/- 4% vs 122 +/- 3%, p = 0.0004), and residual volume percentage of predicted (237 +/- 14% vs 172 +/- 11%, p = 0.0001). Patient HRQL measured using the Dartmouth Primary Care Co-operative Quality of Life questionnaire was more favorable than that reported in aged-care settings. Caregiver burden scale scores indicate caring for a recipient of LVRS carries similar burden to that for caring for individuals with other chronic illnesses. CONCLUSIONS: In this population, a majority of the LVRS patients survived for >/= 3 years. Among survivors, dyspnea and lung function benefits were seen. Baseline BMI and postoperative LOS were significantly associated with survival.

Aged↗

Effect of feedback regarding urinary cotinine and brief tailored advice on home smoking restrictions among low-income parents of children with asthma: a controlled trial.

BACKGROUND: Since most smoker parents of children with asthma are unable to quit, an alternative measure that would reduce their children's exposure to environmental tobacco smoke (ETS) is to ban smoking in the home. METHODS: Compared with 136 usual-care controls, 128 intervention-group parents recruited from South Australian pediatric hospital outpatient waiting rooms were given written and verbal feedback about their 1- to 11-year-old child's urinary cotinine-to-creatinine level, information booklets, and two telephone calls encouraging a ban on smoking at home. RESULTS: At 6 months, 49.2% of the intervention group reported having banned smoking in the home compared with 41.9% of controls, but the differential rate of change from baseline was not significant (P = 0.40). At follow-up, there were no significant differences between groups in the percentage reporting bans on smoking in the car, the mean reduction from baseline in total daily consumption or consumption in front of the child, children's urinary cotinine level, or parental smoking cessation. CONCLUSIONS: The intervention did not change parents' propensity to create or maintain bans on smoking in their homes or otherwise change smoking habits to reduce their children's exposure to ETS. More intensive interventions may be required to achieve change among low-income smoker parents of children with asthma.

Adult↗