Impact of a home-based walking and resistance training program on quality of life in patients with heart failure

Patients with heart failure (HF) often have profound activity limitations and diminished quality of life (QOL) due to symptoms of dyspnea and fatigue. Although recent studies demonstrate positive physiologic and psychological benefits of low to moderate intensity, supervised, aerobic exercise training performed 3 to 5 days/ week for 20 to 40 minutes' duration, in a monitored setting, the efficacy of a home-based exercise program combining endurance and resistance exercise on symptoms and QOL, are unknown. This randomized controlled study examined the efficacy, safety, and adherence rates of a 3-month home-based combined walking and resistance exercise program on symptoms and QOL in 40 women and men aged 30 to 76 years with New York Heart Association class II to III HF. Baseline and 3-month evaluations consisted of a chronic HF questionnaire to assess symptoms and QOL and exercise capacity by symptom-limited treadmill exercise test with respiratory gas analysis. The exercise intervention improved fatigue (p = 0.02), emotional function (p = 0.01), and mastery (p = 0.04). Overall exercise adherence was excellent (90%) and there were no reported adverse events. A moderate intensity home-based combined walking and resistance program for patients with class II to III HF is safe and effective in reducing symptoms and improving QOL.     

Immunity to hepatitis B, poliomyelitis and measles in fully vaccinated Aboriginal and Torres Strait Island children

Objective: To determine the immunity to hepatitis B, poliomyelitis and measles in fully vaccinated Aboriginal and Torres Strait Island children in north Queensland.
Methodology: A cross-sectional survey of immunity in a sample of children; 101 fully vaccinated Aboriginal and Torres Strait Island children, with a median age of 24.5 months, from 10 communities in North Queensland participated in this study. The main outcome measures were the prevalence of adequate antibody levels against hepatitis B, poliomyelitis and measles.
Results: Only 54% (95% Cl 44–63%) of the children had adequate immunity (10 m iu/mL) to hepatitis B, and one child had been infected despite vaccination. Although all the children (95% Cl 96–100%) had adequate immunity (i.e. neutralizing antibodies at a dilution of 1:8) to poliovirus 2, only 93% (95% Cl 86–96%) and 60% (95% Cl 50–69%) had adequate immunity to polioviruses 1 and 3, respectively. Nearly all (96%; 95% Cl 90–98%) of the children had adequate immunity (i.e. detectable IgG antibody) to measles.
Conclusions: Although a relatively low proportion of the children had adequate antibody levels against hepatitis B the clinical significance of this observation is uncertain. Further studies are needed to determine whether fully vaccinated Torres Strait Island children have been adequately protected and whether they require a booster dose of hepatitis B vaccine. A substantial proportion of fully vaccinated Aboriginal and Torres Strait Island children are inadequately protected against poliomyelitis, and therefore any such child with acute flaccid paralysis should be investigated fully for poliomyelitis. Vaccinated Aboriginal and Torres Strait Island children are well protected against measles, as are other Australian children.     

Promoting physical activity: the new imperative for public health

The aim of this essay is to provide an overview of initiatives designed to increase physical activity among different populations and in different settings, and to set the context for the major challenges that lie ahead. The decline in habitual physical activity with modernization, and the causal link between physical activity and health are briefly reviewed. The need to understand physical activity as a health behavior and examples of behavior change theories that have been applied to the promotion of physical activity are discussed. Diverse projects and campaigns in three countries, i.e. South Africa, Australia and the US, are highlighted. Common themes found in these physical activity initiatives include the development of a theory-driven research base, inclusion of behavioral and social scientists on multidisciplinary teams, and advocacy for environmental changes that promote physical activity. Within the next decade, research projects and national campaigns such as those described herein will yield important new findings on how to increase physical activity levels among targeted sectors of the population. The research agenda for the future includes development of both basic and applied research on physical activity, and the integration of theory across social, behavioral and biomedical disciplines.     

Preparation-induced errors in EPR dosimetry of enamel: Pre- and post-crushing sensitivity

Polyakov et al. (1995) showed errors in dose estimation as a function of grain size for enamel grains given beta irradiation after crushing. We tested the effect of gamma irradiation applied to the specimens before and after crushing. We confirmed Polyakov's observations and found that post-crushing irradiation altered the slope of the dose-response curve of the hydroxyapatite signal and produced a grain-size-dependent offset. No changes in the slope of the dose-response curve were seen in enamel caps irradiated whole before crushing.     

Death during jogging or running. A study of 18 cases.

We investigated the circumstances of death and the medical and activity histories of 18 individuals who died during or immediately after jogging. Thirteen men died of coronary heart disease (CHD) and four men and one woman died of other causes. Six CHD subjects had medical histories relevant to the cardiovascular system, but only one had diagnosed CHD. Six CHD subjects experienced prodromal symptoms but continued vigorous exercise programs. Two subjects had exercised less than a month, but most had trained regularly for years. The CHD risk factors for the CHD cases did not differ significantly from those for other age-matched, physically active men. Superior physical fitness does not guarantee protection against exercise deaths. Physicians and exercising adults should be aware of this fact and give appropriate attention to possible prodromal symptoms.     

Effects of cold stress on sleep of an hibernator, the golden-mantled ground squirrel (C. lateralis).

Contrary to previously reported decreased sleep in nonhibernators, sleep patterns of ground squirrels remained unchanged on acute cold exposure (5δC). However, cold exposure did constitute a physiological stress as indicated by a 55% increase in heart rate. Significant increases in sleep time occurred during recovery sleep (22δC) consistent with the more general finding of a strong correlation between sleep length and metabolic rate in mammals.     

Cognitive and mood improvements of caffeine in habitual consumers and habitual non-consumers of caffeine

Rationale The cognitive and mood effects of caffeine are well documented. However, the majority of studies in this area involve caffeine-deprived, habitual caffeine users. It is therefore unclear whether any beneficial findings are due to the positive effects of caffeine or to the alleviation of caffeine withdrawal.Objectives The present placebo-controlled, double-blind, balanced crossover study investigated the acute cognitive and mood effects of caffeine in habitual users and habitual non-users of caffeine.Method Following overnight caffeine withdrawal, 24 habitual caffeine consumers (mean=217 mg/day) and 24 habitual non-consumers (20 mg/day) received a 150 ml drink containing either 75 or 150 mg of caffeine or a matching placebo, at intervals of 48 h. Cognitive and mood assessments were undertaken at baseline and 30 min post-drink. These included the Cognitive Drug Research computerised test battery, two serial subtraction tasks, a sentence verification task and subjective visual analogue mood scales.Results There were no baseline differences between the groups mood or performance. Following caffeine, there were significant improvements in simple reaction time, digit vigilance reaction time, numeric working memory reaction time and sentence verification accuracy, irrespective of group. Self-rated mental fatigue was reduced and ratings of alertness were significantly improved by caffeine independent of group. There were also group effects for rapid visual information processing false alarms and spatial memory accuracy with habitual consumers outperforming non-consumers. There was a single significant interaction of group and treatment effects on jittery ratings. Separate analyses of each groups responses to caffeine revealed overlapping but differential responses to caffeine. Caffeine tended to benefit consumers mood more while improving performance more in the non-consumers.Conclusions These results do not support a withdrawal alleviation model. Differences in the patterns of responses to caffeine by habitual consumers and habitual non-consumers may go some way to explaining why some individuals become caffeine consumers.     

Recovery from impaired dark adaptation in nightblind pregnant Nepali women who receive small daily doses of vitamin A as amaranth leaves, carrots, goat liver, vitamin A-fortified rice, or retinyl palmitate

BACKGROUND: It is not known whether daily consumption of vitamin A-containing foods is efficacious for treating nightblindness. OBJECTIVE: We assessed the effect of supplementation with vitamin A from food or synthetic sources on dark adaptation and plasma retinol concentrations in nightblind pregnant Nepali women. DESIGN: Nightblind pregnant women were randomly assigned to 1 of 6 treatment groups to receive 6 d/wk for 6 wk either 850 microg retinol equivalents/d as retinyl palmitate, vitamin A-fortified rice, goat liver, amaranth leaves, or carrots or 2000 microg retinol equivalents/d as retinyl palmitate. Dark adaptation was assessed weekly by using the pupillary threshold (PT) test; plasma retinol concentrations were measured before and after the intervention. These outcomes were also assessed in a comparison group of nonnightblind pregnant women. RESULTS: In the nightblind women, the mean PT improved significantly (P<0.0001) from -0.71+/-0.04 to -1.42+/-0.02 log cd/m2, and the final mean PT did not differ significantly from that in the nonnightblind women (-1.43+/-0.04; P=0.55). Improvement in dark adaptation was greater in the liver group than in the vitamin A-fortified rice group (P<0.02). Plasma retinol concentrations increased significantly (P<0.0001) from 0.95+/-0.05 to 1.07+/-0.05 micromol/L. The plasma retinol response was greater in the higher-dose capsule and liver groups than in the vegetable groups and significantly greater in the liver group than in the vitamin A-fortified rice group (both: P<0.05). CONCLUSION: Improvement in dark adaptation did not differ significantly between women who received vitamin A as liver, amaranth leaves, carrots, or retinyl palmitate.