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At least 973 records · Page 54Linked to original sources
PubMed2002

Effect of Reiki treatments on functional recovery in patients in poststroke rehabilitation: a pilot study.

OBJECTIVES: The three objectives of this study were: (1) to evaluate the effectiveness of Reiki as an adjunctive treatment for patients with subacute stroke who were receiving standard rehabilitation as inpatients, (2) to evaluate a double-blinded procedure for training Reiki practitioners, and (3) to determine whether or not double-blinded Reiki and sham practitioners could determine which category they were in. DESIGN: A modified double-blinded, placebo-controlled clinical trial with an additional historic control condition. SETTING: The stroke unit of a major rehabilitation hospital. SUBJECTS: Fifty (50) inpatients with subacute ischemic stroke, 31 male and 19 female. INTERVENTIONS: There were four conditions: Reiki master, Reiki practitioner, sham Reiki, and no treatment (historic control). Subjects received up to 10 treatments over a 2(1/2)-week period in addition to standard rehabilitation. OUTCOME MEASURES: Functional independence measure (FIM), and Center for Epidemiologic Studies--Depression (CES-D) measure. RESULTS: No effects of Reiki were found on the FIM or CES-D, although typical effects as a result of age, gender, and time in rehabilitation were detected. Blinded practitioners (sham or reiki) were unable to determine which category they were in. Sham Reiki practitioners reported greater frequency of feeling heat in the hands compared to Reiki practitioners. There was no reported difference between the sham and the real Reiki practitioners in their ability to feel energy flowing through their hands. Post hoc analyses suggested that Reiki may have had limited effects on mood and energy levels. CONCLUSION: Reiki did not have any clinically useful effect on stroke recovery in subacute hospitalized patients receiving standard-of-care rehabilitation therapy. Selective positive effects on mood and energy were not the result of attentional or placebo effects.

Aged↗
PubMed1988

Biotyping of aerobic actinomycetes by modified killer system.

Forty-four yeasts belonging to the genera Pichia, Candida, Saccharomyces and Kluyveromyces were tested for their potential killer effect on 13 aerobic actinomycetes (6 Nocardia asteroides, 1 N. brasiliensis, 1 N. caviae and 5 Actinomadura madurae). Only a few yeast strains did not display any killer activity against the aerobic actinomycetes studied, thus confirming that the killer phenomenon is widespread among microorganisms. For epidemiological purposes, a killer system was developed. According to their susceptibility to the 9 killer yeasts chosen, it was possible to differentiate the Nocardia and Actinomadura isolates into biotypes. Fitting conditions of the killer system to potential sensitive microorganisms with different characteristics of growth are also discussed.

Actinomycetaceae↗
PubMed1999

Low back pain and lifestyle. Part II--Obesity. Information from a population-based sample of 29,424 twin subjects.

STUDY DESIGN: A cross-sectional postal survey of 29,424 twin subjects aged 12-41 years obtained from a population-generated panel. OBJECTIVES: To determine whether obesity is associated with low back pain. SUMMARY OF BACKGROUND DATA: Despite a large number of epidemiologic studies in this area, it is unclear whether obesity and low back pain are positively associated, and if so, whether there is a causal association. METHODS: The association and dose-response connection between body mass index and nonspecific low back pain experienced by subjects in the preceding year were studied. Possible modifying effects of age, gender, type of work, and smoking were investigated. The prevalence of nonspecific low back pain was also studied in monozygotic twin pairs who were dissimilar in body mass index. RESULTS: There was a modest positive association between body mass index and low back pain that increased with the duration of low back pain. The underweight subjects consistently reported lower prevalence of low back pain (odds ratios < 1) than did those higher in weight. The dose-response curve was usually A-shaped. A positive monotonic dose response was apparent mainly in those with long-lasting or recurrent low back pain. The positive association between body mass index and low back pain disappeared when monozygotic twins who were dissimilar in body weight classification were studied. CONCLUSIONS: Obesity is modestly positively associated with low back pain, in particular with chronic or recurrent low back pain. However, because the association is weak, because there is no consistent positive monotonic dose response, and because the link disappears in monozygotic twins who are dissimilar in body mass index, it is unlikely that this association is causal. It is possible, however, that obesity plays a part in the chronicity of simple low back pain. Therefore, those with recurring or long-term low back pain deserve further attention.

Adolescent↗
PubMed2002

Pathways of inflammatory activation in Alzheimer's disease: potential targets for disease modifying drugs.

In the human brain several cell types are capable of initiating and amplifying a brain specific inflammatory response involving the synthesis of cytokines, prostaglandins and oxygen free radicals. In Alzheimer's disease (AD), signs of an inflammatory activation of microglia and astroglia are present inside and outside amyloid deposits. Cell culture and animal models suggest an interactive relationship between inflammatory activation, reduced neuronal functioning and deposition of amyloid. The activation of inflammation-associated enzymes such as p38 mitogen-activated protein kinase (p38 MAPK) and cycloxygenase-2 (COX-2) is not restricted to glial cells but also found in neurons and may contribute to intraneuronal damage. Epidemiological studies have shown a reduced risk of AD among users of anti-inflammatory drugs. Therefore, anti-inflammatory drugs have become the focus of several new treatment strategies. Small clinical trials with non-steroidal anti-inflammatory drugs (NSAIDs) such as indomethacin and diclofenac showed a trend for a disease modifying effect, while clinical trials with steroids did not show a beneficial effect. NSAIDs may not only act on COX-2 but also inhibit COX-1 activity or activate peroxisome proliferator-activated receptor gamma (PPAR gamma). Among promising new strategies to reduce the inflammatory activation in the CNS interfering with intracellular pro-inflammatory pathways has been shown to be effective in various cell culture and animal models. Inhibitors of p38MAPK and PPAR gamma agonists may be suitable agents to suppress inflammatory activation in AD.

Alzheimer Disease↗
PubMed2005

Postprandial hyperglycemia and diabetes complications: is it time to treat?

Increasing evidence suggests that the postprandial state is a contributing factor to the development of atherosclerosis. In diabetes, the postprandial phase is characterized by a rapid and large increase in blood glucose levels, and the possibility that the postprandial "hyperglycemic spikes" may be relevant to the onset of cardiovascular complications has recently received much attention. Epidemiological studies and preliminary intervention studies have shown that postprandial hyperglycemia is a direct and independent risk factor for cardiovascular disease (CVD). Most of the cardiovascular risk factors are modified in the postprandial phase in diabetic subjects and directly affected by an acute increase of glycemia. The mechanisms through which acute hyperglycemia exerts its effects may be identified in the production of free radicals. This alarmingly suggestive body of evidence for a harmful effect of postprandial hyperglycemia on diabetes complications has been sufficient to influence guidelines from key professional scientific societies. Correcting the postprandial hyperglycemia may form part of the strategy for the prevention and management of CVDs in diabetes.

Arteriosclerosis↗
PubMed2004

Cost-effectiveness analysis of tissue plasminogen activator for acute ischemic stroke: a comparative review.

PURPOSE: This work was undertaken to review current evidence of cost-effectiveness analysis (CEA) on thrombolysis for acute ischemic stroke. METHODS: An electronic search via PubMed, from 1995 until May 2004, was performed. The methods undertaken by these studies were examined with particular attention to their modeling assumptions, sources of data, and outcome measures. RESULTS: Three comprehensive CEAs of rtPA (recombinant tissue plasminogen activator) for acute ischemic stroke were reviewed. These studies were from the United States, Canada, and the United Kingdom. All these studies employed the perspective of a healthcare system and used a Markov decision-analytic modelling approach. Estimates of effectiveness of rtPA were based on the National Institute of Neurological Disorders and Stroke (NINDS) rtPA Stroke Trial, literature-derived values or a stroke registry. In each study, functional outcome measured by the modified Rankin Scale was used to represent health states, and quality-adjusted life year gained was the health outcome summary measure. The cost-effectiveness of rtPA therapy varied in magnitude, but seemingly with same positive implications. CONCLUSIONS: Cost-effectiveness analysis requires information on an intervention's effectiveness and country-specific sources of epidemiological and resource utilization data, most of which are not yet available in Taiwan. Despite the limitations, CEA is essential if a healthcare system would like to contain costs while maintaining, or improving, quality of care.

Cost-Benefit Analysis↗
PubMed1986

[The cluster method in conducting epidemiological research].

The Expanded Programme on Immunization (EPI) whose goal is to reduce morbidity and mortality by providing children with immunizations against diphtheria, pertussis, tetanus, poliomyelitis, measles, and tuberculosis continually faces the problem of documenting immunization coverage rates. Therefore the EPI seeks simple, effective, and inexpensive methods of evaluation which could be implemented in different countries. An example of such a method is a simplified cluster sampling technique of estimation of immunization coverage through the examination of 210 children, selected randomly as 30 groups of 7 children each. In 1978-1984 more than 1000 immunization coverage surveys were performed all over the world, mainly in developing countries. In a modified way this method is also used to collect data on morbidity and mortality of certain EPI target diseases as well as diarrhoeal diseases.

Child↗
PubMed1982

A method for using epidemiologic data to estimate the potential impact of an intervention on the health status of a target population.

A general method is proposed for estimating the potential impact of a prevention program involving risk factor modification on the incidence of specific diseases in a target population. An evaluative framework for comparing alternative intervention strategies is also presented. On the basis of results from epidemiologic studies, the user must specify certain parameters regarding the distribution of the risk factor that is to be modified in the population, the magnitude of the association between the risk factor and disease, and the total risk of disease in the population. A quantitative measure, called the potential impact fraction, is derived to estimate the proportion of expected new cases that may be prevented under intervention programs of varying success. Estimates of this measure are then used to assess the potential efficacy, effectiveness, adequacy, and efficiency of planned intervention strategies. The method is illustrated with published data relating relative weight and coronary heart disease among middle-aged U.S. men, comparing different strategies of weight reduction. Key assumptions of the method and interpretation of results are discussed.

Adult↗
PubMed2004

Cigarette smoking, cytochrome P4501A1 polymorphisms, and breast cancer among African-American and white women.

INTRODUCTION: Previous epidemiologic studies suggest that women with variant cytochrome P4501A1 (CYP1A1) genotypes who smoke cigarettes are at increased risk for breast cancer. METHODS: We evaluated the association of breast cancer with CYP1A1 polymorphisms and cigarette smoking in a population-based, case-control study of invasive breast cancer in North Carolina. The study population consisted of 688 cases (271 African Americans and 417 whites) and 702 controls (285 African Americans and 417 whites). Four polymorphisms in CYP1A1 were genotyped using PCR/restriction fragment length polymorphism analysis: M1 (also known as CYP1A1*2A), M2 (CYP1A1*2C), M3 (CYP1A1*3), and M4 (CYP1A1*4) RESULTS: No associations were observed for CYP1A1 variant alleles and breast cancer, ignoring smoking. Among women who smoked for longer than 20 years, a modest positive association was found among women with one or more M1 alleles (odds ratio [OR] = 2.1, 95% confidence interval [CI] = 1.2-3.5) but not among women with non-M1 alleles (OR = 1.2, 95% CI = 0.9-1.6). Odds ratios for smoking longer than 20 years were higher among African-American women with one or more M3 alleles (OR = 2.5, 95% CI = 0.9-7.1) compared with women with non-M3 alleles (OR = 1.3, 95% CI = 0.8-2.2). ORs for smoking in white women did not differ appreciably based upon M2 or M4 genotypes. CONCLUSIONS: Cigarette smoking increases breast cancer risk in women with CYP1A1 M1 variant genotypes and in African-American women with CYP1A1 M3 variant genotypes, but the modifying effects of the CYP1A1 genotype are quite weak.

Black or African American↗
PubMed1990

The protective effect of the oral contraceptive pill on rheumatoid arthritis: an overview of the analytic epidemiological studies using meta-analysis.

The oral contraceptive pill (OCP) has been implicated as having a protective effect on the development of rheumatoid arthritis (RA). The results of 12 studies have now been reported and produced differing results and conclusions. Because of the discrepancy in results and the importance of the issue we undertook a review of the studies and performed a meta-analysis. In all, 9 independent studies satisfied the criteria for selection, 6 case-control design and 3 longitudinal. Using standard meta-analysis techniques, the overall pooled odds ratio for all the studies was 0.68 for the crude results (95% CI 0.58-0.78) and 0.73 for the adjusted results (95% CI 0.61-0.85). The graphical odd-man-out method produced a 94% interval of 0.70-0.72. The pooled odds ratio of the case-control studies was lower than for the longitudinal studies. However, subdividing studies by the type of case source produced a pooled odds ratio for studies using hospital-based cases of 0.49 (95% CI 0.39-0.63) which was considerably less than that of studies using population-based cases: 0.95 (0.78-1.16). This difference was unlikely to have explained by bias due to selection of controls. We suggest that OCP use may not have a "protective effect" on the development of RA but may prevent the progression to severe disease by modifying the disease process.

Arthritis, Rheumatoid↗
PubMed2006

A protocol for investigation of the effects of outdoor air pollution on stroke incidence, phenotypes and survival using the South London Stroke Register.

Stroke is a major cause of death and disability. About 5.3 million people die every year from stroke worldwide with over 9 million people surviving at any one time after suffering a stroke. About 1 in 4 men and 1 in 5 women aged 45 years will suffer a stroke if they live to their 85th year. It is estimated that by 2023 there will be an absolute increase in the number of people experiencing a first ever stroke of about 30% compared with 1983. In the UK, stroke is the third commonest cause of death and the most common cause of adult physical disability and consumes 5% of the health and social services budget. Stroke is assuming strategic public health importance because of increased awareness in society, an ageing population and emerging new treatments. It is an NHS health service and research priority, being identified as a target in Our Healthier Nation and the NSF for Older People for prevention and risk factor control and in the NHS Plan as a disease requiring intermediate care planning and reduction in inequalities of care. Whilst a number of risk factors for stroke are well known (e.g. increasing age, ethnicity, socioeconomic deprivation, hypertension), the potential importance of outdoor air pollution as a modifiable risk factor is much less well recognised. This is because studies to date are inconclusive or have methodological limitations. In Sheffield, we estimated that 11% of stroke deaths may be linked to current levels of outdoor air pollution and this high figure is explained by the fact that so many people are exposed to air pollution.We plan to study the effects of outdoor air pollution on stroke using a series of epidemiological (i.e. population based) studies. The purpose of this project is: to examine if short term increases in pollution can trigger a stroke in susceptible individuals, to investigate if the occurrence of stroke is higher amongst people living in more polluted areas (which would be explained by a combination of exposure to short term increases and longer term exposure to higher pollution levels), and to see if people living in more polluted areas have reduced survival following their stroke. We will use geographical information systems, robust statistical methods and powerful grid computing facilities to link and analyse the data. The datasets we will use are the South London Stroke Register database, daily monitored pollution data from national monitoring networks and modelled pollution data for London from the Greater London Authority. The South London Stroke Register records information on all patients who suffer a stroke ("incident" cases) living within a defined area. This stroke incidence dataset offers major advantages over previous studies examining the effects of pollution on hospital admissions and mortality, as not all patients with stroke are admitted or die and there may be a delay between the onset of stroke and admission or death. In addition, it contains other useful information, particularly the type of stroke people have suffered. Air pollution is a potentially modifiable risk factor for stroke. This study will provide robust population level evidence regarding the effects of outdoor air pollution on stroke. If it confirms the link, it will suggest to policy-makers at national and international levels that targeting policy interventions at high pollution areas may be a feasible option for stroke prevention.

Adult↗
PubMed2005

Could visible light contribute to the development of leukaemia and other cancers in children?

This paper suggests to rigorously test the hypothesis that there are causal links between visible light and the development of leukaemia and other cancers in children. Light can be considered as a candidate risk factor because it suppresses melatonin biosynthesis which may play a role in a series of anticancer defences. Indeed, melatonin may offer some protection against all "hallmarks of cancer" [i.e., self-sufficiency in growth signals; insensitivity to growth-inhibitory signals; evasion of programmed cell death (apoptosis); limitless replicative potential; sustained angiogenesis; tissue invasion and metastasis] recently suggested by Hanahan and Weinberg. Already ongoing investigations into the possible nexus of light, endocrine systems and the development of cancers will be further fueled by recent insights into photoreception and -- transduction, including the discovery of "novel" photoreceptors in the eye. Among a variety of different photosensory tasks, these receptors constitute crucial gates for light information from the environment which is employed for the temporal organization of our physiology and it has been proposed that chronodisruption, i.e., a significant disturbance of the coordination and thus order of biological rhythms, could contribute to the development of cancers. With regard to public health, the pervasive exposures to light -- at work and in homes -- imply that visible radiation could be a strong risk factor defined epidemiologically as a causal contributor to disease in a large proportion of cases. Importantly, if light were to be corroborated as a contributor to cancers in children, it would be amenable to manipulations with the perspective of reducing inherent risks significantly. In fact, it could be much easier -- and much more effective -- to reevaluate and modify lighting systems than to manipulate other possible determinants of the chronic processes of cancer such as genetic, nutritional or lifestyle factors.

Child↗
PubMed2003

Is aortic stenosis a preventable disease?

Aortic stenosis (AS) is the most common valvular disease requiring valve replacement. Its prevalence increases with age. When the severity of AS is only mild to moderate, it is well tolerated. When it becomes severe, AS confers significant morbidity and mortality. Adverse events can be avoided if it is possible to prevent or retard the progression from mild or moderate AS to severe AS. Progression of AS parallels the progression of sclerotic changes involving the aortic valve, which share histological and immunochemical similarities with the process of atherosclerosis. Far from being just a degenerative process, the development of AS is a complex and highly regulated process with a number of modifiable factors. One of the key factors appears to be lipoproteins, which are intimately involved in several pathways crucial to the development of AS. The importance of lipoproteins is further supported by epidemiological and clinical studies showing a strong association between lipoproteins and AS. The time has come to initiate prospective studies to assess the effect of cholesterol lowering on the progression of AS.

Animals↗
PubMed1997

Role of fetal and infant growth in programming metabolism in later life.

Fetal growth and development is dependent upon the nutritional, hormonal and metabolic environment provided by the mother. Any disturbance in this environment can modify early fetal development with possible long-term outcomes as demonstrated by extensive work on 'programming'. Growth restriction resulting from a deficit in tissue/organ cell number (as measured by tissue DNA content) is irrecoverable. However, when the cell size (or cell protein content) is reduced, the effects on growth may not be permanent. Recent epidemiological studies using archival records of anthropometric measurements related to early growth in humans have shown strong statistical associations between these indices of early development and diseases in later life. It has been hypothesised that the processes explaining these associations involve adaptive changes in fetal organ development in response to maternal and fetal malnutrition. These adaptations may permanently alter adult metabolism in a way which is beneficial to survival under continued conditions of malnutrition but detrimental when nutrition is abundant. This hypothesis is being tested in a rat model which involves studying the growth and metabolism in the offspring of rat dams fed a low-protein diet during pregnancy and/or lactation. Using this rat model, it has been demonstrated that there is: (i) Permanent growth retardation in offspring nursed by dams fed a low-protein diet. (ii) Permanent and selective changes in organ growth. Essential organs like the brain and lungs are relatively protected from reduction in growth at the expense of visceral organs such as the liver, pancreas, muscle and spleen. (iii) Programming of liver metabolism as reflected by permanent changes in activities of key hepatic enzymes of glycolysis and gluconeogenesis (glucokinase and phosphoenolpyruvate carboxykinase) in a direction which would potentially bias the liver towards a 'starved' setting. We have speculated that these changes could be a result of altered periportal and perivenous regions of the liver which may also affect other aspects of hepatic function. (iv) Deterioration in glucose tolerance with age. (v) An increase in the life span of offspring exposed to maternal protein restriction only during the lactation period, and a decrease in life span when exposed to maternal protein restriction only during gestation. These studies show that hepatic metabolism and even longevity can be programmed by events during early life.

Animals↗
PubMed1997

Adenocarcinomas of the esophagus and gastric cardia: the role of diet.

The incidence of adenocarcinomas of the esophagus and gastric cardia (ACEGC) has been increasing for the past 10-15 years in the United States. The reason for this increase is unknown. This hospital-based case-control study was conducted to assess the effects of dietary and nutritional factors on the risk of ACECG. A total of 95 incident cases with pathological diagnosis and 132 cancer-free controls were included in the study. Patients were recruited at Memorial Sloan-Kettering Cancer Center from 1 November 1992 to 1 November 1994. Epidemiologic data were collected by a modified National Cancer Institute Health Habits History Questionnaire. Nutritional and dietary factors were analyzed using a logistic regression model. Increased risk of ACEGC was significantly related to higher intake of dietary calories and fat after controlling for several potential confounding factors. Decreased risk of ACEGC was significantly associated with high ingestion of dietary fiber, lutein, niacin, vitamin B6, iron, and zinc. Higher intakes of vitamin A, beta-carotene, vitamin E, folate, phosphorus, and potassium were associated with a decreased risk of the disease, but these were not statistically significant. The study suggests that ACEGC can be preventable through dietary interventions.

Adenocarcinoma↗
PubMed1992

Reproductive factors in breast cancer epidemiology.

There is abundant epidemiologic evidence showing that early menarche, late menopause, low parity and late age at first birth are related to increased risk of breast cancer. However, in younger age groups, uniparous women seem to be at higher risk than nulliparous, and the effect of later pregnancies is less clear in this group. Intervals between pregnancies may modify the general protective effect. Some studies have indicated an adverse effect of late age at pregnancies after the first. Further studies are necessary to determine if the general protective effect of pregnancies after the first is preceded by a transient increase in breast cancer risk. No clear association has been established with number of abortions. Results from two large prospective studies suggest that breast feeding is not strongly related to risk of breast cancer among Western populations.

Abortion, Induced↗
PubMed1992

Depressive symptoms and weight change in a national cohort of adults.

To assess the influence of depressive symptoms (defined using the CES-D) on weight change, we analysed data from 1794 adults, aged 25-74 years, who participated in the first National Health and Nutrition Examination Survey in 1971-1975 and the National Health Epidemiologic Follow-up Study in 1982-1984. After adjusting for baseline covariates using multiple linear regression, the data show that younger men (< 55 years) who were depressed at baseline gained nearly 3 kg more over the follow-up period than those who were not depressed. Among these younger men, however, education modified the effect of depression on weight change; those with < 12 years of education gained more weight with depression than those with more education (6.2 vs. 1.2 kg, respectively; P < or = 0.01). In contrast, depressed younger women gained slightly less weight than those who were not depressed. Among younger women, education also modified the effects of depression on weight change; those with < 12 years of education gained less weight with depression than those with more education (-3.2 vs. 0.6 kg, respectively; P < or = 0.01). Among older people (> or = 55 years), both men and women who were depressed lost more weight than those who were not depressed. Depression may play a substantial role in the patterns of weight change among adults in the United States. These patterns of weight change may contribute to the adverse health effects associated with depression.

Adult↗
PubMed1997

[Individual autonomy and the principles of occupational health care].

The effect of work-related diseases on the health condition of the population at large has increased the interest in etiology and epidemiology of these diseases and intensified activities aimed at providing effective treatment of occupational diseases, but first of all at preventing their occurrence. That is why workers are now recognised as the largest population group subjected to active counselling. In order to meet the recommendations of the International Labour Organization, Polish labour law has been modified so that every worker is guaranteed an opportunity to benefit from medical prevention within the range required by his/her working conditions. This concern for workers' health contributed to the fact that health has now become a supreme value to which all other values and human needs are submitted. The author discusses the issues of compulsory prophylactic examinations and protection against employment at a workplace that is inadmissible because of health reasons, in the perspective of the human right to keep his/her own ailments in secret and the right to freedom of choice concerning his/her own health and living and conditions.

Environmental Monitoring↗