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PubMed2002

Minor recurrent aphthous stomatitis and smoking: an epidemiological study measuring plasma cotinine.

OBJECTIVE: To compare blood cotinine levels between a group of patients with minor recurrent aphthous stomatitis (RAS) and a group representative of the general population, matched for age and gender. SETTING: Although smoking has been implicated as a protective factor in RAS, few studies have compared the prevalence of smoking in RAS patients with population controls. Cotinine is a smoking derivative with a long half-life in the circulation. Measurement of plasma cotinine levels provides an accurate and objective measurement of an individual's cigarette consumption. METHODS: Blood samples were taken from 84 RAS patients and 81 controls. A microplate enzyme immunoassay (EIA) was used to detect plasma cotinine levels. RESULTS: The number of RAS patients [2 (2.4%)] who were smokers (plasma cotinine > 25 microg ml(-1) was significantly lower than in the control group [12 (14.8%); P = 0.00102]. Furthermore, the mean cotinine level amongst smokers in the RAS group was significantly lower than in smokers in the control group (P = 0.0068). CONCLUSION: This study shows that a group of RAS patients is significantly less likely to contain smokers than a matched control population, and among smokers the level of cigarette use was significantly lower in RAS patients than the control population. The perceived negative association between RAS and smoking was supported by this epidemiological study.

Adult↗
PubMed2005

Erythropoietin response in critically ill mechanically ventilated patients: a prospective observational study.

INTRODUCTION: Anemia is a common problem in critically ill patients. The etiology of anemia of critical illness is often determined to be multifactorial in the clinical setting, but the pathophysiology remains to be elucidated. Erythropoietin (EPO) is an endogenous glycoprotein hormone that serves as the primary stimulus for erythropoiesis. Recent evidence has demonstrated a blunted EPO response as a factor contributing to anemia of critical illness in specific subsets of patients. Critically ill patients requiring mechanical ventilation who exhibit anemia have not been the subject of previous studies. Our goal was to evaluate the erythropoietic response to anemia in the critically ill mechanically ventilated patient. METHODS: A prospective observational study was undertaken in the medical intensive care unit of a tertiary care, military hospital. Twenty patients admitted to the medical intensive care unit requiring mechanical ventilation for at least 72 hours were enrolled as study patients. EPO levels and complete blood count were measured 72 hours after admission and initiation of mechanical ventilation. Admission clinical and demographic data were recorded, and patients were followed for the duration of mechanical ventilation. Twenty patients diagnosed with iron deficiency anemia in the outpatient setting were enrolled as a control population. Control patients had baseline complete blood count and iron panel recorded by primary care physicians. EPO levels were measured at the time of enrollment in conjunction with complete blood count. RESULTS: The mean EPO level for the control population was 60.9 mU/ml. The mean EPO level in the mechanically ventilated patient group was 28.7 mU/ml, which was significantly less than in the control group (P = 0.035). The mean hemoglobin value was not significantly different between groups (10.6 g/dl in mechanically ventilated patients versus 10.2 g/dl in control patients; P > 0.05). CONCLUSION: Mechanically ventilated patients demonstrate a blunted EPO response to anemia. Further study of therapies directed at treating anemia of critical illness and evaluating its potential impact on mechanical ventilation outcomes and mortality is warranted.

Aged↗
PubMed2000

Increased premature mortality of competitive powerlifters suspected to have used anabolic agents.

Misuse of supraphysiological doses of anabolic steroids is claimed to have serious side effects. The aim of the study was to determine the mortality, and the cause of premature deaths among a group of subjects who are strongly suspected to have used anabolic steroids for a non-medical purpose over several years. The mortality of 62 male powerlifters placed 1st-5th in weight series 82.5-125 kg in Finnish championships during 1977-1982 was compared with the mortality of population controls. The mortality during the 12-year follow-up was 12.9% for the powerlifters compared to 3.1% in the control population. By 1993 eight of 62 powerlifters and 34 of 1094 population controls had died, thus the risk of death among the powerlifters was 4.6 times higher (95% CI 2.04-10.45; p = 0.0002). The causes of premature death among the powerlifters were suicide (3), acute myocardial infarction (3), hepatic coma (1) and non-Hodgkin's lymphoma (1). These findings add to the growing amount of evidence of an association between anabolic steroid abuse and premature death, and support the view that measures to decrease AAS misuse among both competitive and amateur athletes are justified.

Adult↗
PubMed2006

The role of self-defined race/ethnicity in population structure control.

Population-based association studies are powerful tools for the genetic mapping of complex diseases. However, this method is sensitive to potential confounding by population structure. While statistical methods that use genetic markers to detect and control for population structure have been the focus of current literature, the utility of self-defined race/ethnicity in controlling for population structure has been controversial. In this study of 1334 individuals, who self-identified as either African American, European American or Hispanic, we demonstrated that when the true underlying genetic structure and the self-defined racial/ethnic groups were roughly in agreement with each other, the self-defined race/ethnicity information was useful in the control of population structure.

Black or African American↗
PubMed2003

Bleomycin-induced chromosome breaks as a risk marker for lung cancer: a case-control study with population and hospital controls.

Environmental exposure to carcinogens and individual susceptibility play significant roles in cancer risk. Suboptimal DNA repair capability, measured by quantifying mutagen-induced chromosome breaks, might explain variable host susceptibility to environmental carcinogens. In an ongoing lung cancer case-control study, we compared individual sensitivity to bleomycin-induced chromosome breaks in 152 non-small cell lung cancer patients with 94 population controls and 85 hospital controls with no history of cancer. Mutagen sensitivity was measured by mean number of chromatid breaks per cell in cultured peripheral blood lymphocytes treated with bleomycin. Non-parametric tests and chi(2) tests were used to determine the statistical significance of the crude case-control comparisons, followed by logistic regression to adjust for important covariates. The mean number of bleomycin-induced breaks per cell was 1.01 for the cases compared with 0.86 for hospital controls (P < 0.01) and 0.89 for population controls (P < 0.01). The mean number of breaks per cell was 1.01 for those >65 years old and 0.81 for those < or = 65 years old (P < 0.01) among population controls. Defining bleomycin sensitive as >0.84 break/cell (the median level in population controls), 67% of the cases were bleomycin sensitive compared with 49% of the hospital controls [adjusted odds ratio (OR) = 2.69, 95% confidence interval (CI) = 1.44, 5.04], and 51% of the population controls (adjusted OR = 2.18, 95% CI = 1.13, 4.21). Our data indicate that the increased number of bleomycin-induced chromosome breaks was significantly associated with an increased risk of lung cancer in the first 331 subjects.

Aged↗
PubMed1995

Assessment of physical activity in daily life.

The absence of physical activity represents a major risk factor for coronary heart disease. Therefore, the evaluation of physical activity is a very current topic within the framework of epidemiologic studies. The aim of this study, based on the Baecke questionnaire, was to compare the various indices [leisure time activity index (LAI) and sport activity index (SAI)] obtained in a control population (control group) with those obtained in a population presenting risks of coronary disease [cardiovascular risk factor (CVRF)]. The control group consisted of 195 volunteers and the CVRF group of 69. All volunteers were between 27 and 60 years of age and had similar professional activities; therefore, the occupation activity index (OAI) evaluated in the original Baecke questionnaire was not taken into account. Maximal oxygen consumption (VO2max) was calculated for each volunteer using the indirect method involving shuttle run tests. The results have shown a direct correlation between SAI and VO2max in the control group (r = 0.309; p < 0.01), whereas VO2max did not appear to be correlated with the SAI in the CVRF group. This is probably because the VO2max value is underestimated. The use of indirect methods in populations presenting risk factors for coronary disease may be inappropriate, as the psychological attitude of the volunteers towards physical activity must be taken into account. Multiple regression analyses revealed that in both groups, 30% of the VO2max variations could be predicted by parallel variations in the mass of body fat and of the SAI, although the influence of these parameters is different in the two study groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Mapping disease genes: family-based association studies.

With recent rapid advances in mapping of the human genome, including highly polymorphic and closely linked markers, studies of marker associations with disease are increasingly relevant for mapping disease genes. The use of nuclear-family data in association studies was initially developed to avoid possible ethnic mismatching between patients and randomly ascertained controls. The parental marker alleles not transmitted to an affected child or never transmitted to an affected sib pair form the so-called AFBAC (affected family-based controls) population. In this paper, the theoretical foundation of the AFBAC method is proved for any single-locus model of disease and for any nuclear family-based ascertainment scheme. In a random-mating population, when there is a marker association with disease, the AFBAC population provides an unbiased estimate of the overall population (control) marker alleles when the recombination fraction (theta) between the marker and disease genes is sufficiently small that it can be taken as zero (theta = 0). With population stratification, only marker associations present in the subpopulations will be detected with family-based analyses. Of more importance, however, is the fact that, when theta not equal to 0, differences between transmitted parental (patient) marker allele frequencies and non- or never-transmitted parental marker allele frequencies (implying a marker association with disease) can only be observed for marker genes linked to a disease gene (theta < 1/2). Thus, associations of unlinked marker loci with disease at the population level, caused by population stratification, migration, or admixture, are eliminated. This validates the use of family-based association tests as an appropriate strategy for mapping disease genes.

Chromosome Mapping↗
PubMed1989

Foam at inner eye canthus in office workers, compared with an average Danish population as control group.

Foam formation in the eye canthus is well-known. The presence of foam was observed in 169 office workers in 4 town halls in Copenhagen County compared with 112 control persons from the general population in the same area. The presence of foam depends on age and gender. A significant increase with age was observed in the control population (P = 0.0078). In both groups, females had a significantly lower occurrence of foam than males (P = 0.0043, P = 0.010). This difference was mainly caused by the use of eye make-up. After correction for age, gender and use of eye make-up, the prevalence of foam was significantly lower in the office population than in the control population (P less than 0.0001). Furthermore, low foam formation was significantly correlated to reported subjective eye irritation in the office population (P = 0.0074), but not in the control population (P = 0.40). Also, significant positive correlation between absence of foam and different degrees of dry eyes (expressed as a combination of premature break-up of the precorneal tearfilm and lissamine green stained epithelial damage of the bulbar conjunctiva) was found both in the office population and in the control population (P = 0.0090, P = 0.0034). However, after correction for the more frequent appearance of dry eyes in the office population, foam was still observed significantly less frequently in the office population than in the control population (P = 0.0001). It is concluded that the decreased foam formation in the office worker constitutes a key symptom in the development of 'office eye syndrome'. In what way the office environment influences the foam formation is unknown. Possible mechanisms are discussed.

Adult↗
PubMed1987

Resolution on family planning, 10 July 1987.

On 10 July 1987 the People's Congress Standing Committee of Guangxi adopted a Resolution on strengthening family planning work and strictly controlling population growth. The Resolution reads as follows: "Over the past few years, our region has scored some achievements in promoting family planning work. Quite a few areas have not firmly grasped family planning work, but have perfunctorily carried out ideological work and shown a poor command of the relevant policies, thus bringing about an excessively fast population growth rate. Moreover, our region is currently entering a new fertility peak. Therefore, we are faced with the very arduous tasks of fulfilling the population program listed in the Seventh 5-Year Plan and the population control targets set for the last years of this century." The Resolution adds: "We must strengthen the management and supply of contraceptives, raise the technical standards of sterilization, and improve services in this regard. We must also strengthen the management of family planning work concerning the floating population. Financial departments at all levels must successfully arrange the funds essential for family planning work. Judicial organs at all levels must strike severe blows at all illegal and criminal activities disrupting family planning work."

Asia↗
PubMedDate not supplied

The effect of total shoulder arthroplasty on self-assessed health status is comparable to that of total hip arthroplasty and coronary artery bypass grafting.

The purpose of this study was to assess the impact of total shoulder arthroplasty on the self-assessed health status of a large series of patients with glenohumeral osteoarthritis. In 91 patients we were able to compare the 8 quantitative domains of Short Form-36 (SF-36) before surgery and at 30 to 60 months after surgery. These preoperative and postoperative scores were compared with data from an age- and gender-matched control population. These results were also compared with those reported for patients who underwent other common, effective surgical procedures. Preoperative SF-36 values were significantly lower than population controls for 6 of 8 SF-36 domains (physical function, social function, physical role function, emotional role function, vitality, and comfort). Patients improved significantly in 4 of 8 SF-36 domains at 30 to 60 months after total shoulder arthroplasty: physical role function (P <.01), comfort (P <.01), social function (P <.01), and mental health (P <.05). Although the improvements were significant and similar to the postoperative scores reported for total hip arthroplasty and coronary bypass procedures, the scores did not reach those of the general population.

Aged↗
PubMed1986

Survival, prognosis, and causes of death in rheumatoid arthritis.

The factors associated with mortality were examined in a prospective longitudinal study, over an average of 12 years, with 94% followup of patients diagnosed as having rheumatoid arthritis. Of 805 patients, 233 died during the period of the study. Survivorship of rheumatoid arthritis patients was approximately 50% less than that of population controls. Survivorship was decreased by the traditional demographic variables of greater age and male sex; however, a significant independent effect of variables reflecting disease severity (American Rheumatism Association functional class, rheumatoid factor titer, number of involved joints) was identified by multivariate analysis. Seventy-nine excess deaths (i.e., those that would not have been expected in a control population) were due in part to disease-related causes, to infections, and to gastrointestinal complications of therapy. Treatment with gold or prednisone did not seem to affect survivorship or cause of death, except for the clustering of deaths of patients with vasculitis within the prednisone group. Our findings indicate that rheumatoid arthritis, a chronic disabling disease, is also associated with a major decrease in survivorship.

Age Factors↗
PubMed2001

Total mortality is increased in rheumatoid arthritis. A 17-year prospective study.

The purpose of this study was to determine the total and cause-specific mortality in rheumatoid arthritis (RA) patients compared to a control population in northern Norway. One hundred and eighty-seven patients with RA and 930 population controls matched for age, gender and municipality were followed until death or for a maximum of 17 years. The total mortality in RA patients was twice that of their controls (MRR = 2.0, 95% CI = 1.6-2.5). Patients possessing serum rheumatoid factors did not have a higher relative mortality than the seronegative patients. There was no statistically significant increased mortality from cancer or cardiovascular diseases. Indications for a higher death rate in RA patients than in controls were found for infection and sudden death.

Adult↗
PubMed2005

Mitochondrial DNA mutations in patients with postlingual, nonsyndromic hearing impairment.

Mitochondrial mutations have previously been reported anecdotally in families with maternally inherited, nonsyndromic hearing impairment. To ascertain the contribution of mitochondrial mutations to postlingual but early-onset, nonsyndromic hearing impairment, we screened patients collected from within two different populations (southern Italy and UK) for previously reported mtDNA mutations associated with hearing disorders. Primer extension (SNP analysis) was used to screen for specific mutations, revealing cases of heteroplasmy and its extent. The most frequently implicated tRNA genes, Leu(UUR) and Ser(UCN), were also sequenced in all Italian patients. All tRNA genes were sequenced in those UK patients showing the clearest likelihood of maternal inheritance. Causative mtDNA mutations were found in approximately 5% of patients in both populations, representing almost 10% of cases that were clearly familial. Age of onset, where known, was generally before adulthood, and hearing loss was typically progressive. Haplogroup analysis revealed a possible excess of haplogroup cluster HV in the patients, compared with population controls, but of borderline statistical significance. In contrast, we did not find any of the previously reported mtDNA mutations, nor a significant deviation from haplogroup cluster frequencies typical of the control population, in patients with late adult-onset hearing loss (age-related hearing impairment) from the UK or Finland.

Age of Onset↗
PubMed2001

Impaired endothelium-dependent vasodilatation in renal failure in humans.

BACKGROUND: The main causes of death in patients with chronic renal failure (CRF) are cardiovascular complications. The aim of the present study was to compare endothelium-dependent vasodilatation (EDV) in patients with chronic renal failure with a control population controlling for hypertension, diabetes mellitus and hypercholesterolaemia. METHODS: Fifty-six patients with moderate CRF (mean creatinine clearance 29.4 ml/min/1.73 m(2)) underwent evaluation of EDV and endothelium-independent vasodilatation (EIDV) by means of forearm blood flow (FBF) measurements with venous occlusion plethysmography during local intra-arterial infusions of methacholine (Mch, 2 and 4 microg/min evaluating EDV) and sodium nitroprusside (SNP, 5 and 10 microg/min evaluating EIDV). Fifty-six control subjects without renal impairment underwent the same investigation. RESULTS: Infusion of Mch increased FBF significantly less in patients with renal failure than in controls (198 vs 374%, P<0.001), whereas no significant difference was seen regarding the vasodilatation induced by SNP (278 vs 269%). The differences in EDV between the groups were still significant after controlling for hypertension, blood glucose, and serum cholesterol in multiple regression analysis (P<0.001). EDV was related to serum creatinine (r=-0.37, P<0.01), creatinine clearance (r=0.45, P<0.005) and to serum triglyceride levels (r=-0.29, P<0.005) in the CRF group. CONCLUSIONS: Patients with moderate CRF have an impaired EDV even after correction for traditional cardiovascular risk factors and this impairment is related to the degree of renal failure.

Aged↗
PubMed1985

Antifertility effect of busulfan and procarbazine in male and female coyotes.

Antifertility effects of two cytostatic agents, busulfan and procarbazine, were evaluated using 43 captive breeding pairs of adult coyotes. Nineteen pairs served as untreated controls. Only the male or female of remaining pairs was treated. Females received either 8 mg busulfan/kg or 6 mg procarbazine/kg just prior to onset of the breeding season. Males were treated once with either 8 mg busulfan/kg just before onset of breeding or with 4 mg busulfan/kg or 6 mg procarbazine/kg about 1 mo before onset of the breeding season. Uterine implantation sites were counted in females of all breeding pairs postpartum via laparotomy. Busulfan given to males at 4 mg/kg or to either females or males at 8 mg/kg significantly reduced implantation sites compared to untreated controls. Thus, busulfan may be successful in controlling population in coyotes in the field where both the male and female of a breeding pair may ingest the compound. However, multiple doses at a lower rate would be preferred because dosages greater than 10 mg/kg resulted in mortality. Although procarbazine has a mode of action similar to busulfan, doses of 6 mg procarbazine/kg did not reduce implantation sites or disrupt normal spermatogenesis. Increased doses need to be evaluated before effectiveness of procarbazine for coyote population control can be determined.

Animals↗
PubMed1985

Influence of selection for milk yield on endogenous hormones and metabolites in Holstein heifers and cows.

Plasma concentrations of prolactin (PRL), growth hormone (GH), insulin, glucagon, glucose, urea and free fatty acids (FFA) were measured in Holstein calves, yearlings, bred heifers and primiparous cows, either sired by bulls with high predicted differences (PD) for milk (selection group) or by bulls from an unselected random bred control population (control group; n = 6). Serial blood samples were collected before and after feeding for an 8-h period from 0900 to 1700 h. All animals were fed a complete feed at 1100 h and administered insulin (.6 IU/100 kg body weight) at 1400 h. Mean plasma PRL was greater in control animals after feeding and insulin administration, while GH was greater overall in selection cattle. Insulin remained elevated longer in selection animals after exogenous administration, and plasma glucagon was increased in the control group. While plasma glucose and urea were unaffected by genetic group, plasma FFA were elevated in selection group calves and primiparous cows compared with the control group. All hormones and metabolites differed among the pre- and post-feeding and insulin administration periods and also with age. Mean PRL and GH increased after feeding, while glucagon decreased after exogenous insulin. Plasma FFA declined after feeding, while urea and glucose were similar before and after feeding. Mean PRL increased and glucagon decreased with advancing age and plasma GH and insulin showed inverse relationships at different ages. Plasma FFA changes closely followed GH changes with age, while plasma glucose more closely followed insulin changes with age. Results indicate that all hormones measured and FFA responded to genetic selection for milk, and increases in GH are uniformly associated with increased genetic potential for milk yield.

Animals↗
PubMed1996

Adolescent milk, dairy product and fruit consumption and testicular cancer.

There is an association between dairy product consumption and the incidence of testicular cancer in different countries. To test the hypothesis that milk and dairy products are risk factors, a case-control study was performed in East Anglia, UK. All the cases were men with testicular cancer and for each of the 200 cases there were four controls, two cancer controls and two population controls. The response rate of those eligible subjects who received a questionnaire was: cases 73%, cancer controls 65% and population controls 57%. All responding subjects completed a dietary questionnaire including questions on current and adolescent milk, dairy product and fruit and vegetable consumption. The answers were corroborated when possible by the subjects' mothers using a separate questionnaire. Cases consumed significantly more milk in adolescence than population controls, but this difference did not apply to other dairy products or fruit. The consumption of milk by cancer controls was intermediate between cases and population controls. Cancer controls with non-epithelial cancers had a milk consumption similar to cases, whereas subjects with epithelial cancers had a consumption similar to population controls. In a multivariate analysis the odds ratio between cases and population controls for the association of undescended testis and testicular cancer was 7.19 (95% CI 2.36-21.9) and for each extra quarter pint of milk consumed it was 1.39 (95% CI 1.19-1.63).

Adolescent↗