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PubMed2001

Epidemiology of multiple system atrophy. ESGAP Consortium. European Study Group on Atypical Parkinsonisms.

Multiple system atrophy (MSA) is a form of atypical parkinsonism with unknown etiology. The epidemiological studies conducted up to now on this disease are scarce. The incidence rate is about 0.6 cases per 100,000 persons per year. The prevalence rates show 4-5 cases per 100,000 persons. In Italy, about 4,900 prevalent cases have been estimated. The mean onset age is about 54 years; the median survival is 7-9 years. Only one case-control study has been performed on this disease. This study showed an increased risk of MSA associated with occupational exposure to organic solvents, plastic monomers and additives, pesticides and metals. Smoking habits seem to be less frequent in MSA cases (as in Parkinson's disease cases) than in healthy controls. Quinn's clinical criteria and those of the Consensus Conference promoted by the American Academy of Neurology are in fair agreement. We have performed a case-control study on 73 MSA cases, 146 hospital controls and 73 population controls.

Age of Onset↗
PubMed2001

Epidemiology of progressive supranuclear palsy. ESGAP Consortium. European Study Group on Atypical Parkinsonisms.

Progressive supranuclear palsy (PSP) is a rare form of parkinsonism. The incidence rates are about 0.3-1.1 cases per 100,000 persons. The only two case-control studies performed up to now show conflictual results as regards education and residence in rural areas. Recently, a cluster of PSP and atypical parkinsonism has been observed in French Antilles. The hypothesis is that a consumption of both tropical fruit and herbal tea may be associated with PSP onset. Some PSP families with a probably autosomal dominant transmission have been described. A high frequency of a tau haplotype (H1/H1) associated with PSP is reported by some authors. The significance of this association is still not clear. We have performed a case-control study on 58 PSP cases, 116 hospital controls and 58 population controls.

Age of Onset↗
PubMed1993

Development defects of enamel in humans with hereditary epidermolysis bullosa.

Developmental defects of enamel are often reported as a feature of the more severe forms of epidermolysis bullosa (EB). The purpose of this investigation was to determine the prevalence and character of enamel defects in each of the major hereditary EB types. Clinical evaluations were made on 237 individuals representing all of the major EB types and 58 unaffected individuals. All EB cases were categorized by phenotype, mode of inheritance and skin biopsy. The frequency of individuals having developmental enamel defects ranged from 8.6% in recessive dystrophic EB to 100% in junctional EB; 27.5% of the control population had these defects. Generalized hypoplasia characterized by either severe pitting and/or thin enamel was seen in all junctional EB cases but not in any other EB type. There was a tendency for the severe Herlitz form of junctional EB to have thin enamel while non-Herlitz junctional EB cases had less severe pitting and generally no reduction in enamel thickness. The prevalence of individuals with hypoplastic enamel bands was greater in the EB population (9.7%) than controls (1.9%). Thus individuals with simplex and dominant dystrophic EB typically have enamel defects that are similar in frequency and distribution to those of unaffected individuals. Developmental defects of enamel are a consistent feature of junctional EB, although the clinical expression is highly variable.

Adolescent↗
PubMed1987

Increased risk for lethal forms of liver disease among HBsAg-positive blood donors in the United States.

We have used a death-record search to define the frequency of lethal outcomes of hepatitis B virus infection among a population of more than 15,000 overtly healthy blood donors found positive in routine HBsAg testing. We have compared the study population with a control group of some 18,000 donors selected on the basis of a negative test result. The index and control groups were observed for periods reflecting a total of 55 and 59 thousand person-years, respectively. Twenty percent of the 134 deaths identified among HBsAg positive donors were in some way liver related, including seven deaths due to hepatitis, seven to cirrhosis and six to hepatoma. In contrast, only one of the 95 deaths in the control population was liver related, and was due to fatty degeneration of the liver. The majority (four) of the hepatoma deaths occurred among blacks, three of whom were less than 35 at the time of death. In contrast, deaths from cirrhosis were all among whites. We conclude that there is significant mortality associated with the HBsAg positive state, even though the affected individuals may be asymptomatic and well enough to give blood at some stage. We estimate the standardised mortality ratio for hepatoma among HBsAg-positive persons in the United States is at least 27, confirming the association observed in other populations. The risk for hepatoma among young, HBsAg positive black males appears to approach that reported for HBsAg positive males in Taiwan. Data on the feasibility of AFP testing for early detection of hepatoma are included and discussed.

Blood Donors↗
PubMed1992

Prevalence of markers of hepatotropic viruses among drug addicts in Warsaw, Poland.

We studied 100 unselected parenteral drug abusers for infection with hepatitis C, B, A and D virus (HCV, HBV, HAV and HDV). Seventy-six percent had serological evidence of HCV infection. 12% were positive for HBsAg and at least one marker of HBV infection was present in 69%. These results were significantly higher than in a matched control population. Compared to controls, the prevalence of anti-HAV (65%) was not significantly increased in drug addicts. Of the anti-HCV-positive drug addicts, 80.3% had at least one marker of HBV infection compared to 33.3% of anti-HCV-negative cases (p less than 0.001). No such correlation was found between the prevalence of HCV or HBV infection markers and the presence of anti-HAV. Antibodies against HDV were detected in 16 (16%) of the samples from drug addicts. No significant association was found between antibodies to HCV and gender, age and duration of drug abuse. The risk of HBV infection increased significantly with years of drug abuse but was not associated with age and sex. The presence of anti-HAV was related to age only. Sixteen (16%) of the subjects were definitely positive for anti-HIV-1, but at the time of the study they were asymptomatic. No significant association was found between the presence of anti-HIV and the prevalence of serological markers of HBV, HCV, HAV and HDV infection.

Adolescent↗
PubMed2006

Ginsenoside content and variation among and within American ginseng (Panax quinquefolius L.) populations.

The contents of five ginsenosides (Rg1, Re, Rb1, Rc and Rd) were measured in American ginseng roots collected from 10 populations grown in Maryland. Ginsenoside contents and compositions varied significantly among populations and protopanaxatriol (Rg1 and Re) ginsenosides were inversely correlated within root samples and among populations. The most abundant ginsenoside within a root and by population was either Rg1 or Re, followed by Rb1. Ginseng populations surveyed grouped into two chemotypes based on the relative compositions of Rg1 and Re. Four populations, including the control population in which plants were grown from TN and WI seed sources, contained roots with the recognized chemotype for American ginseng of low Rg1 composition relative to Re. The remaining 6 populations possessed roots with a distinctive chemotype of high relative Rg1 to Re compositions. Chemotype did not vary by production type (wild versus cultivated) and roots within a population rarely exhibited chemotypes different from the overall population chemotype. These results provide support for recent evidence that relative Rg1 to Re ginsenoside contents in American ginseng roots vary by region and that these differences are likely influenced more by genotype than environmental factors. Because the physiological and medicinal effects of different ginsenosides differ and can even be oppositional, our findings indicate the need for fingerprinting ginseng samples for regulation and recommended usage. Also, the High Rg1/Low Re chemotype discovered in MD could potentially be used therapeutically for coronary health based on recent evidence of the positive effects of Rg1 on vascular growth.

Chromatography, High Pressure Liquid↗
PubMed1997

Functional aspects of apoptosis in hematopoiesis and consequences of failure.

Apoptosis is an internally directed, physiological method of cell destruction. Cellular components are dismantled within the confines of an intact cell membrane, and rapid ingestion by phagocytic cells prevents local inflammation. A variety of genes have now been identified as positive or negative regulators of apoptosis. Transfection experiments and studies of gene cooperation in viral transformation suggest that full cellular transformation requires not only the deregulation of proliferation, but also the inhibition of concomitant apoptosis programs. The regulation of apoptosis is fundamental to hematopoietic homeostasis. Stem cell renewal is continuously counterbalanced by apoptosis in functionally inactive or terminally differentiated cells. Extensive cell death in developing lymphocyte populations ensures that only cells recognizing non-self antigens are released into the periphery, and the finite lifespan of terminally differentiated cells enables the extensive cell turnover demanded by functional aspects of the hematopoietic system. The requirement of each hematopoietic sub-population for a specific sub-set of survival factors, provides a flexible mechanism for dictating the cellular composition of the mature population and for controlling population size. Surplus cell production and apoptosis are therefore normal features of hematopoiesis. The consequences of deregulated apoptosis are severe. Excessive apoptosis in lymphocyte populations plays a major role in the pathogenesis of acquired immunodeficiency syndrome (AIDS), whereas ineffective apoptosis has been associated with the development of inflammation, autoimmunity and hematological malignancies. The identification of various genetic abnormalities which influence apoptosis in leukaemic cells (e.g., mutant p53, Bcr-Abl and over-expression of Bcl-2), suggests that the acquisition of an anti-apoptotic lesions is an important event in the multi-step evolution of hematological malignancies. In addition, the nature of some leukaemias particularly the chronic leukemias, in which the leukemic cells are nonproliferative and long lived, suggests that anti-apoptotic lesions are early events in the pathogenesis of these diseases. It is likely that the utilization of mechanisms to evade apoptosis would facilitate disease progression in all leukemias and contribute to the development of multi-drug resistance. A better understanding of apoptosis mechanisms in hematopoietic cells, and their exploitation by leukemic cells should be useful in the development of improved cytotoxic regimes.

Acquired Immunodeficiency Syndrome↗
PubMed2002

Risk of diabetes-related amputation in South Asians vs. Europeans in the UK.

AIMS: To compare the risk of and risk factors for diabetes-related amputation in South Asians and Europeans. METHODS: This was a population-based case control study based in the health districts of Bolton, Oldham and Central Manchester in the UK. Cases with diabetes-related amputation performed between 1992 and 1997 (n = 172) and controls with diabetes and no amputation (n = 376) were selected from the primary care-based North-west Diabetes Foot Study database. Risk factor data were also collected. RESULTS: Age at diagnosis adjusted odds ratio (OR) of amputation in South Asians compared with Europeans was 0.26, 95% confidence interval (CI) 0.11-0.65, P = 0.004. In the control population, South Asians were less likely than Europeans to have peripheral vascular disease (PVD) (9% vs. 24%, P = 0.02), neuropathy (30% vs. 54%, P = 0.003), and less likely to have ever been smokers (31% vs. 57%, P = 0.03). When these factors were added to the model, the OR was attenuated to 0.84, 95% CI 0.23-3.08, P = 0.8. CONCLUSIONS: South Asians with diabetes have about a quarter of the risk of amputation of Europeans. This is mostly explained by low rates of PVD and neuropathy in South Asians, in part associated with low rates of smoking. The reasons for the South Asian protection from both PVD and neuropathy deserve further exploration.

Age of Onset↗
PubMed1999

A case-controlled multicenter study of vasovagal reactions in blood donors: influence of sex, age, donation status, weight, blood pressure, and pulse.

BACKGROUND: Vasovagal reactions occur in a small, but significant number of blood donors. These reactions may decrease return donation and disrupt blood collection activities. The purpose of this study was to define the contributory role of sex, age, weight, blood pressure, and pulse in vasovagal reactions with syncope in blood donors. STUDY DESIGN AND METHODS: A retrospective case-control study involved 1890 blood donors with syncope from three large United States blood centers during 1994 and 1995. Case controls and random population controls were used in a logistic regression analysis to determine the significance of individual variables to syncopal reactions. RESULTS: Female donors, young donors, first-time donors, low-weight donors, and donors with low predonation blood pressure had higher absolute donation reaction rates than other donors. When each variable was adjusted for other variables by regression analysis, age, weight, and donation status (first-time or repeat donor) were significant (p<0.0001), and sex, predonation blood pressure, and predonation pulse were not. The most important variables, in descending order, were age, weight, and donation status (first-time or repeat donor). CONCLUSIONS: Donation-related vasovagal syncopal reactions are a multifactorial process determined largely by age, weight, and first-time donor status.

Adult↗
PubMed1990

Predation and control of laboratory populations of the snail Biomphalaria glabrata by the freshwater prawn Macrobrachium rosenbergii.

Laboratory experiments were conducted on predation by the giant freshwater prawn, Macrobrachium rosenbergii, on Biomphalaria glabrata, a snail intermediate host of human schistosomiasis. Prawns greater than 22 mm carapace length could consume snails of any size. Smaller prawns exhibited a size-specific upper limit on the size of snail they could kill. Below the maximum size of prey consumed, little selectivity for prey size was demonstrated. All prawns heavier than 2.5 g killed the largest size of snail offered (16 mm diameter). Consumption, in terms of the numbers of snails killed, and the snails' wet weight and percentage of prawn body weight eaten per day, increased with prawn size. Large prawns consumed snails at a high rate (39% of body weight per day). Population experiments demonstrated that a prawn of 25 mm carapace length could eliminate 95% of a population of 80 snails in a 20-1 aquarium within 20 days and all snails by day 40. A prawn of 15 mm carapace length could not eliminate all snails. Large snails (24% of the initial population) had some protection from predation because of their size. Although the snails bred continuously, no snails were able to recruit to these populations in the presence of small prawns. In contrast, snail populations in control aquaria without prawns expanded to a mean of 919 snails by the end of the experiment (day 70). Since M. rosenbergii are voracious predators on B. glabrata, exhibit considerable habitat overlap with the snail prey, and are likely to treat snails as highly preferred food, further experimentation on these prawns in the context of biological control of schistosomiasis is warranted. The ready availability of prawns through established prawn hatcheries and the synergistic use of these prawns in aquaculture may ensure the reliability of stocking procedures and meet the standards of availability and cost-effectiveness required of a biological control agent. Polyculture of Macrobrachium with fin fish (Tilapia) indicates that these prawns may be a particularly useful control agent in aquacultural environments.

Animals↗
PubMed2006

Fecundity in Drosophila following desiccation is dependent on nutrition and selection regime.

Life-history trade-offs of populations of Drosophila melanogaster selected for enhanced desiccation resistance (D populations) include increased pupal mortality, retarded development, increased longevity, and decreased fecundity. We tested the effects of acute desiccation on fecundity and the effects of various nutritional regimes on fecundity following a bout of desiccation in the D populations and their control populations (C populations). Female flies were desiccated for 8 h (C populations) or 24 h (D populations) and then recovered on one of four treatments: distilled water, a saline solution, a saline and sucrose solution, or food. Each treatment was tested in the presence and absence of a yeast supplement. Fecundity was then measured on an oviposition medium over a 12-h period. Fecundity was also measured in flies that did not undergo a desiccation stress. Yeast increased fecundity under all conditions examined in the C populations but not in the D populations. There was an overall effect of recovery treatment on fecundity but no effect of desiccation stress.

Animal Nutritional Physiological Phenomena↗
PubMed2002

Studies on the human leukocyte antigen-DR in patients with endometriosis: genotyping of HLA-DRB1 alleles.

BACKGROUND: An increasing number of reports suggest that endometriosis is associated with abnormal immune function involving changes in both cell-mediated and humoral immunity, although the aetiology of the disease remains undefined. The human leukocyte antigen system (HLA) is known to play a role in the aetiology of a number of diseases. This study examines the possible association between the HLA-DR and endometriosis. METHODS: Eighty-three patients diagnosed with endometriosis by laparoscopic examination were typed for HLA-DR antigens using a PCR-restriction fragment length polymorphism analysis. The frequency of HLA-DR genotypes in this patient population was compared with that in a population of general controls. RESULTS: The incidence of HLA-DRB1*1403 in the patient group was 6.0% (10/166 alleles) compared with 1.4% in the control group (6/444 alleles), and the incidence of the HLA-DRB1*1403 allele was significantly greater in patients with endometriosis compared with the control population [odds ratio 4.68, 95% confidence interval 1.67-13.09, P = 0.0013 (chi(2) analysis), (corrected P values: Pc = 0.0494)]. No significant difference was found between the two groups with regards to the frequency of the other HLA-DR alleles. CONCLUSIONS: The results from this study may be helpful to implicate a role of HLA-DR antigens in the development of endometriosis, although further investigation is required.

Alleles↗
PubMed1989

Occupation and bladder cancer in Spain: a multi-centre case-control study.

A case-control study on bladder cancer was carried out in four regions of Spain. The study included 497 cases (438 males and 59 females), 583 hospital controls and 530 population controls matched by sex, age and residence. The present paper reports the results of the analyses on occupational history. Among men, an increased risk of bladder cancer was found for textile workers (OR = 1.97, 95% CL 1.2-3.3), mechanics and maintenance workers (OR = 1.86, 95% CL 1.2-2.8), workers in the printing industry (OR = 2.06, 95% CL 1.0-4.3) and for managers (OR = 2.03, 95% CL 1.2-3.5). The risk was highest among those first employed in the textile industry before the age of 25 and prior to 1960. Among mechanics the risk was highest for those who started after the age of 25 and later than 1960. The OR for smokers who had also been employed in one of the high risk occupations was 7.82 (95% CL 4.4-14.0) which is compatible with a multiplicative effect of joint exposure to tobacco and occupational hazards.

Aged↗
PubMed1992

Occupational and environmental hazards associated with lung cancer.

In a hospital-based case-control study 194 lung cancer cases, 194 hospital controls, and 194 population controls were interviewed for their smoking, occupational, and residential history by trained interviewers, using a standardized questionnaire. In order to include many different environmental exposures, case ascertainment took place in seven different hospitals with catchment areas ranging from rural to highly industrialized. Lung cancer risk strongly increases with cumulative cigarette dose, reaching an odds ratio (OR) of 16.19 (95% confidence limits (CL): 5.10, 51.33) for male smokers of more than 40 pack-years and an OR of 19.99 (95% CL: 4.98, 80.24) for female smokers of more than 20 pack-years. For the quantification of occupational exposure to known carcinogens of the lung a novel approach was developed which accumulates exposure information obtained by supplemental questionnaires through an automatic procedure. The OR for the highest exposure group in males was 2.7 (95% CL: 1.23, 5.78). Significantly increased risks were observed in the metal industry, particularly in smelter and foundry workers (OR 4.8, 95% CL: 1.15, 20.16) and in turners (OR 2.2, 95% CL: 1.05, 4.75). In the construction industry the risks were particularly high in road construction workers (OR 3.7, 95% CL: 1.06, 13.20) and in unskilled construction workers (OR 2.7, 95% CL: 1.24, 5.76). The risks in these occupational groups increased with duration and with latency. Quantification of air pollution was done on a county basis by time period. An index based on emission data for sulphur dioxide was compared to a semiquantitative index, which included additional information on ambient air pollution. After adjustment for smoking and occupational exposures an OR of 1.01 (95% CL: 0.53, 1.91) for an emission index and of 1.16 (95% CL: 0.64, 2.13) for a semiquantitative index was obtained.

Adult↗
PubMed1991

Tobacco smoke inhalation pattern, tobacco type, and bladder cancer in Spain.

The association between tobacco smoking and bladder cancer was investigated in a multicenter case-control study conducted in five provinces of Spain between 1983 and 1986. A matched analysis was carried out in males, based on 430 histologically confirmed cases, 405 hospital controls, and 386 population controls, matched by age and place of residence. An increased risk was found for smokers as compared with nonsmokers (odds ratio (OR) = 3.79, 95% confidence intervals (CI) 2.41-5.97), and this increase was significantly associated with the intensity of smoking. Smokers of filter-tipped cigarettes had a reduced risk as compared with smokers of non-filter-tipped cigarettes (OR = 0.57, 95% CI 0.32-1.02). A diminution of risk was also observed for smokers of low-tar and low-nicotine ("light") cigarettes. Depth of inhalation was strongly associated with illness. No difference was shown in the logistic regression model between smokers of black tobacco and smokers of blond tobacco after controlling for depth of inhalation. Although the number of persons who smoked blond tobacco exclusively was small, the results suggest that it is important to consider inhalation patterns when studying risk variations between smokers of black tobacco and smokers of blond tobacco. The age at which a person started to smoke did not appear to affect risk. An analysis of the decrease in risk associated with years since quitting smoking suggested that different components of cigarette smoke may play a role at different stages of the carcinogenic process.

Female↗
PubMed2001

Impact of antibiotic resistance on clinical outcomes and the cost of care.

Antibiotic-resistant organisms are common in intensive care unit infection and can be either Gram-positive or Gram-negative. A number of studies have evaluated whether these organisms can lead to excess morbidity, mortality, or cost. In general, the studies are confounded by a number of methodologic issues, including the selection of an appropriate control population. Cases and controls must be appropriately matched for the presence of infection, the presence of infection with similar organisms (but ones that are either antibiotic-sensitive or -resistant), and severity of illness. In addition, studies must account for the therapies given to patients who are infected with resistant organisms because resistance is an important risk factor for inadequate empirical therapy, and such therapy is itself a potent determinant of a number of adverse outcomes, including mortality. To date, the data with methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococcus are inconsistent with regard to the effect on mortality rates, although infection with both organisms can lead to excess length of stay and increased cost of care. When studies have been adequately controlled and powered, infection with vancomycin-resistant enterococcus has had more of an effect on the mortality rate than infection with antibiotic-sensitive enterococci. Infection with resistant Gram-negatives also has adverse impact on outcome, with excess mortality being seen in patient groups infected with Acinetobacter and Pseudomonas aeruginosa. If we are to minimize the effect of resistance on medical outcomes and cost, it will be necessary to have a current knowledge of each intensive care unit's pathogens and susceptibility patterns, so that empirical therapy will have a good likelihood of being effective. In addition, new therapeutic agents may improve on the efficacy of older agents and could reduce cost if they allow for some patients to leave the hospital and to finish therapy with an oral formulation of a highly bioavailable agent.

Cross Infection↗
PubMedDate not supplied

Activity monitors can detect brisk walking in patients with chronic obstructive pulmonary disease.

PURPOSE: Brisk walking forms the foundation of aerobic training regimes within a pulmonary rehabilitation service for patients with chronic obstructive pulmonary disease (COPD). Repeated bouts of aerobic training are encouraged in the domestic environment. This study was designed to examine the discriminatory properties of an activity monitor, to assess if brisk walking can be identified clearly from all other activities of daily living. Secondly, the authors examined the overall level of activity generated by patients with COPD compared with a healthy control population. METHODS: Eleven patients with COPD and nine age-matched healthy controls were recruited. All subjects were required to wear an activity monitor for 48 hours. Subjects simultaneously recorded their activity (grouped into 10 categories) to the nearest minute. RESULTS: The data indicated that the monitors can detect brisk walking as a distinct activity in patients and a control population. The healthy individuals achieve a significantly higher level of activity than patients, but that the duration of this high intensity activity (i.e., brisk walking) is significantly lower than the patient group. Total activity was not correlated with age, sex, or forced expiratory volume in 1 second. CONCLUSION: Activity monitors have the capacity to discriminate brisk walking from other domestic activities and can be used to identify low levels of domestic activity in the patient population.

Activities of Daily Living↗
PubMed2000

No association of the 5' promoter region polymorphism of CYP17 with breast cancer risk in Japan.

To examine the association between breast cancer risk and a T-to-C substitution polymorphism at the 5' promoter region of CYP17, a case-control study was conducted at Aichi Cancer Center Hospital in Japan. Subjects were 144 histologically confirmed breast cancer patients diagnosed in the past 4 years and 166 hospital controls without cancer. Allele frequency among controls was 44.9% (95% confidence interval; 39.5 - 50.2) for C allele. Odds ratio (OR) of the polymorphism relative to TT-genotype was 0.97 (0.58 - 1.64) for TC-genotype and 0.81 (0.39 - 1.68) for CC-genotype. Subgroup analyses revealed that the OR was not statistically significant for the subgroups stratified by interval after diagnosis, age at menarche, age at first birth, menopausal status, body mass index, and mother / sisters' history of breast cancer. Consistent with previous studies conducted in other countries, the 5' promoter region polymorphism of CYP17 affected breast cancer risk of Japanese women to a limited extent. Although this is not a large-scale case-control study with population controls, these findings provide enough information to discourage further studies on the association between this polymorphism and breast cancer risk in Japan at large, and suggest that this polymorphism is useless for breast cancer risk estimation.

Adult↗