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At least 541 records · Page 30Linked to original sources
PubMedDate not supplied

Association of polymorphisms of interleukin-1 beta gene and Helicobacter pylori infection with the risk of gastric ulcer.

BACKGROUND/AIMS: Interleukin-1 beta (IL-1 beta) plays an important role in gastric inflammation and physiology. Functional polymorphisms of IL-1 beta gene have been related to different risks of gastric cancer and duodenal ulcer but their role in gastric ulcer remains unknown. In this study, we investigate a plausible association between gastric ulcer and the polymorphisms in the IL-1 beta and IL-1 receptor antagonist (IL-1RN) genes. The relationships among the cytokine genotyping, other environmental risks such as Helicobacter pylori infection and smoking, and clinical characteristics of gastric ulcer were also determined. METHODOLOGY: Peripheral blood DNAs from 120 unrelated Taiwan Chinese patients with gastric ulcer and 238 ethnically matched healthy controls were genotyped for the promoter (position -31 and -511) and Taq I polymorphism (position +3954) in the IL-1 beta gene and the variable number of tandem repeats polymorphisms in intron 2 of the IL-1RN gene. The status of Helicobacter pylori infection was determined by serology. RESULTS: The seropositive rate of Helicobacter pylori (95/120 vs. 134/238, OR: 2.95, 95%CI 1.77-4.91), habitual smoking (67/120 vs. 82/238, OR: 2.40, 95%CI 1.54-3.77) and blood group O (63/120 vs. 98/238, OR: 1.55, 95%CI 1.0-2.41) were significantly higher in patients with gastric ulcer than controls. The distributions of allele frequencies of IL-1 beta (-31 C/T or -511 C/T or +3954) and IL-1RN were similar between patients with gastric ulcer and controls. No significant differences were observed, including those analyzed after stratification of the infected population and by the ulcer subgroup. CONCLUSIONS: Our data suggested that Helicobacter pylori infection, cigarette smoking, and blood group O are risk factors of gastric ulcer and IL-1 beta or IL-1RN polymorphisms do not influence susceptibility to gastric ulcer in a Taiwanese population.

Aged↗
PubMed1989

Primary care utilization in Israel--analysis of national data.

Analysis of data from the 1981 National Health Services Utilization Survey was carried out in order to identify factors relevant to primary care utilization in Israel on a semi-quantitative basis. The analysis consisted of stratification of the sample population into age- and sex-groups and the use of a logistic regression model for each stratum. Within the strata age still played a major role in explaining the probability of utilization; in addition, origin, employment status and education were also significant for most strata. In men aged greater than or equal to 65, living arrangements (alone, with spouse or with children) affected utilization. These findings were consistent with previous published reports and with findings of small-scale studies in Israel.

Adolescent↗
PubMed1995

[Measles seroprevalence in the schoolchildren of Valencia. The Measles Study Group].

BACKGROUND: People born between 1978 and 1982 were the most affected by measles in the outbreaks occurring in the Valencian Community (Spain) in 1993. This age group has not been systematically immunized against measles and has not suffered the last large measles epidemics. HYPOTHESIS: global seroprevalence against measles in this age group is inadequate to prevent new outbreaks. METHODS: Prospective seroepidemiologic study in a sample of school-attending children, born between 1978 and 1982. Randomized sampling of all classrooms 5th to 8th grade high school of a Health Area; stratification depending on the population of the village (< 5,000, 5,001-20,000, > 20,000 inhabitants). Antecedents of measles immunization and the disease were collected. Measles IgG antibodies were measured by enzyme immunoassay, antibody titers 1:80 or higher were considered protective. RESULTS: Sample of 410 subjects, belonging to 17 classes. Measles antibody prevalence was 80.2% (95% CI: 76.6-83.8%), and was higher in less populated villages (p < 0.03). Immunization status was known in 253 subjects (61.7%). Protective titers were present in 86.1% of the vaccinated and in 68.1% of the non vaccinated (p < 0.001). CONCLUSIONS: There is a large percentage of subjects born between 1978 and 1982 unprotected against measles. Elimination of the disease will not be able unless an extraordinary vaccination campaign to include these subjects is taken.

Adolescent↗
PubMed1994

[DNA ploidy of stem cells and prognosis of ductal adenocarcinoma of the pancreas].

The findings on DNA stem line ploidy of ductal adenocarcinomas of the pancreas, which have hitherto been published in the literature, are rather contradictory last but not least due to methodological problems. Thus, the DNA stem line ploidy and its prognostic significance were examined by Feulgen image cytometry on 10 microns sections of 100 paraffin-embedded radically resected ductal carcinomas of the pancreas from the records. In that process the parts of the tumour with the highest grade of malignancy were preferentially investigated. The aneuploidy rate (42%) was conspicuously low if compared with other adenocarcinomas. A highly significant positive correlation between DNA ploidy and histological grading according to Klöppel et al. could be observed, while there was only a tendency towards a positive correlation of DNA ploidy and post-surgical tumour stage. Regarding the 1-year survival rate, the DNA aneuploid tumour cases were significantly more unfavourable than the DNA peridiploid ones (p < 0.05). The prognostically decisive parameter, however, was the histological grading (p < 0.00005), which also showed the best stratification of the patient population. However, contrary to expectations the postsurgical stage of the primary tumour and the nodular state were only of low prognostic significance. The reason for that is on the one hand that the distribution over the pT-stages (in 81% pT2 tumours) is unbalanced, and on the other hand that the actual tumour cell dissemination is only insufficiently represented in the post-surgical staging.

Adenocarcinoma↗
PubMedDate not supplied

Predictors of prognosis in patients awaiting heart transplantation.

Patients enrolled in a clinical heart transplantation program were evaluated to identify the predictors of prognosis in patients with advanced heart disease and to optimize timing of heart transplantation. Three hundred eighty-eight subjects were consecutively evaluated from 1985 through 1989. One hundred eighty-four patients (47.5%) had dilated cardiomyopathy; 164 patients (42.2%) had ischemic heart disease; 34 patients (8.8%) had valvular heart disease, and six patients (1.5%) had miscellaneous disorders. In each patient, 45 different parameters were considered. During follow-up (mean, 8.4 months) 166 patients underwent heart transplantation; 99 patients died (heart failure, 66 patients; sudden death, 26 patients; thromboembolism, two patients; noncardiac causes, five patients). The actuarial survival was 83% at 3 months, 77% at 6 months, 73% at 9 months, 70% at 1 year, and 59% at 2 years. The median survival time was 28 months. Analysis by Cox proportional hazard regression model revealed seven independent and significant prognostic factors: etiology (p < 0.05), NYHA class (p < 0.05), third heart sound (p < 0.05), diastolic pulmonary artery pressure (p < 0.05), pulmonary wedge pressure (p < 0.01), mean systemic blood pressure (p < 0.05), and cardiac output (p < 0.05). Cox's analysis allows the computation of patient-specific curves for predictions of residual survival time at any moment during follow-up. Moreover it can be used to calculate a simple prognostic index, which enables stratification of the patient population into three risk classes: patients at high (n = 105), intermediate (n = 160) and low (n = 123) risk of early death. Pairwise comparisons of survival between the classes were significant at 1% level.

Adolescent↗
PubMed1997

Ambulatory system to aid in decision making and risk stratification in postinfarction patients.

Knowledge of the clinical and electrophysiological features of certain cardiovascular risk groups, the adaptation and specialization of clinical protocols, the availability of tools to make determinations for use in patient follow-up and to assess the efficacy of the treatments applied, and the proper processing of different parameters can aid in decision making, leading to the application of a given therapeutic approach, and can facilitate the performance of group and multicenter studies. To address these needs, a simple, low-cost, portable ECG processing system has been designed that complements the current techniques for managing patients with ischemic heart disease and nonmalignant ventricular arrhythmias. This system, consisting of an electrocardiograph and a laptop PC, determines the following parameters on the basis of the ECG: incidence of arrhythmia, heart rate variability, QT dispersion, ECG criteria for ventricular hypertrophy and late potentials. Left ventricular ejection fraction and diastolic function (according to Doppler ultrasound) and other basic epidemiological parameters are typed in. Moreover, the system integrates these parameters, which have usually been considered separately, to arrive at second-level indicators with a greater predictive capacity during the long-term follow-up of patients with ischemic heart disease and ventricular arrhythmias, thus providing an idea of the risk of mortality and the onset of arrhythmic events and allowing risk stratification in this patient population. Finally, the system includes a database of all the patients analyzed, with tools that make it possible to follow the course of their disease and to assess the efficacy of the treatments applied.

Arrhythmias, Cardiac↗
PubMed2004

Postpartum haemorrhage in nulliparous women: incidence and risk factors in low and high risk women. A Dutch population-based cohort study on standard (> or = 500 ml) and severe (> or = 1000 ml) postpartum haemorrhage.

OBJECTIVE: To determine the incidence and risk factors for standard and severe postpartum haemorrhage (PPH) in vaginally delivering nulliparous women, before and after risk stratification. STUDY DESIGN: A population-based cohort study in an unselected cohort nulliparous women (N = 3464) in 'The Zaanstreek' district, The Netherlands. Risk stratification is part of routine care, where midwives cover all obstetrical care for women with low risk pregnancies. RESULTS: The incidence of standard PPH (> or = 500 ml) and severe PPH (> or = 1000 ml) were 19 and 4.2%, respectively. A retained placenta occurred in 1.8%. These data show consistently slightly higher values as compared to studies in literature. The most important risk factors for standard and severe PPH were related to an abnormal third stage of labour-third stage > or = 30 min and retained placenta (in severe PPH: odds ratio (OR) 14.1, 95% confidence interval (CI) 10.4-19.1). High birth weight and perineal damage were less important, but independent, significant risk factors. In the low risk group (N = 1416), incidence of severe PPH was 4.0%. Independent risk factors for severe PPH were third stage > or = 30 min (incidence 7.1%, OR 3.6) and retained placenta (incidence 1.2%, OR 21.6). In 25% of the women with a prolonged third stage (> or = 30 min), third stage was complicated due to retained placenta and/or severe PPH (1.8% of the low risk group). CONCLUSIONS: The incidence of PPH in nulliparous women in this cohort was on average higher than published data, while the most important risk factors for standard and severe PPH, even after risk stratification, were the same. A prolonged third stage of labour has to be considered as abnormal, requiring specific action.

Cohort Studies↗
PubMed1998

Diseases in European historical populations and their effects on individuals and society.

Traditionally, populations are considered "historical" when first written evidences appear. Cultural development with all it's features--agricultural innovations and as a consequence--population growth, social specialisation and stratification, and finally--urbanisation trigger new environmental conditions, among them also in epidemiological situation, that have the feedback effects on the population and the individual. At this time only qualitative evaluations on many of questions can be presented. This paper is an attempt to synthesize available data on the following specific topics related to Medieval/Early Modern European population welfare: nutritional intake, malnutrition and famine; great epidemics and their consequences; spreading of specific infectious diseases (tuberculosis, syphilis, leprosy), which also had a great social resonance in those times, professional diseases. Considerations on their impact on demographical situation (life expectancy, birth rate), life quality and physical development and body build of an individual are also presented. Finally, possibilities for directional selection and impact on modern genetic diversity in Europe are discussed.

Communicable Diseases↗
PubMed2006

Sudden death secondary to cardiac arrhythmias: mechanisms and treatment strategies.

PURPOSE OF REVIEW: This article reviews mechanisms and available therapeutic options for arrhythmias leading to sudden cardiac death in patients with coronary artery disease. RECENT FINDINGS: Intensive efforts have led to a better understanding of the pathophysiology and various treatments of sudden cardiac death. Antiarrhythmic medications have not demonstrated a survival benefit. Beta-adrenergic blocking agents have been revalidated in recent studies to improve survival and reduce risk of sudden cardiac death in patients with myocardial infarction. Angiotensin-converting enzyme inhibitors and aldosterone antagonists should also be used in these patients. Data from randomized trials demonstrate significant survival benefit with an implantable cardioverter-defibrillator and indications have expanded. Patients with established ischemic cardiomyopathy do not require electrophysiologic studies for induction of tachyarrhythmias based on these trials. One recent trial did not demonstrate mortality reduction with implantable defibrillators in patients with recent myocardial infarction. Devices may not provide survival benefit in patients with advanced New York Heart Association class IV heart failure. SUMMARY: The incidence of arrhythmia-related sudden death in the general population remains relatively high. Better risk stratification tools are needed to identify high-risk patients in the general population and in those with known coronary disease and to exclude low-risk patients.

Adrenergic beta-Antagonists↗
PubMed1996

Gene mapping in Gypsies identifies a novel demyelinating neuropathy on chromosome 8q24.

Founder effect and linkage disequilibrium have been successfully exploited to map single gene disorders, and the study of isolated populations is emerging as a major approach to the investigation of genetically complex diseases. In the search for genetic isolates ranging from Pacific islands to Middle East deserts, the 10 million Gypsies resident in Europe have largely escaped the attention of geneticists. Because of their geographical ubiquity, lack of written history and the presumed social and cultural nature of their isolation, Gypsies are construed as not meeting the criteria for a well defined founder population. Gypsy society has a complex structure with subdivisions and stratifications that are incomprehensible to the surrounding populations. Marginalization by the health care systems in most countries results in a lack of information on causes of morbidity and mortality and little is known about hereditary disorders or the population genetic characteristics of Gypsies. This study is the first example of mapping a disease gene in endogamous Gypsy groups. Using lod score analysis and linkage disequilibrium, we have located a novel demyelinating neuropathy to a narrow interval on chromosome 8q24. We show that the disease, occurring in Gypsy groups of different identity and history of migrations, is caused by a single mutation whose origin predates the divergence of these groups.

Adolescent↗
PubMedDate not supplied

Frequency of focal cerebral transient ischemic attacks during a 12 month period. The Copenhagen city heart study.

As an offshoot of a larger prospective cardiovascular population study, the present study aimed to determine the 12 months frequency of focal cerebral transient ischemic attacks (TIAs) in persons randomly selected after age stratification from the Copenhagen city population register. A questionnaire of 5 questions pertaining to cerebrovascular attacks sustained within the last 12 months was distributed to 2,357 persons. The TIA-questionnaire was returned by 88%, of whom 22% responded affirmatively to one or more questions. The positive responders were interviewed by phone, and when suspected of having TIAs they were examined by a neurologist. A total of 11 persons proved to have had TIAs, which for the age group of 60 years and over gives o 12 months frequency of 8/1000. Dizziness, ophthalmologic problems and migraine were the most frequent causes of a "false" positive response.

Aged↗
PubMed1994

The impact of implantable cardioverter defibrillator therapy on health care systems.

Implantable cardioverter defibrillators (ICDs) are now widely used for the secondary prevention of sudden cardiac death and are being offered as a primary preventive therapy. This technology has potential for significant fiscal impact on health care budgets. Technologic innovation will result in more complex devices that are more effective and better accepted by patients and physicians. The clinical impact of these devices will be predicated, in part, by absolute survival benefits but also by their relative advantages over alternative therapies in terms of survival, safety, morbidity, quality of life, and cost. The impact on public health will depend on the effectiveness of screening methods for identification of populations likely to benefit from primary prevention. Risk stratification algorithms are now being tested in several ongoing clinical trials. Dilution of benefit by competing illnesses may occur to different extents in individual patient populations. The economic impact is predicated on the future cost of ICD systems, limitation of hospitalization costs associated with this therapy, and accurate prospective stratification in primary prevention populations. Cost efficacy analyses and quality of life assessment in ongoing and future clinical trials are essential to the development of this therapy and its diffusion into different health care systems. Achievement of clinical benefits, functional independence, and a return to gainful employment by patients will be important determinants of the support lent by health care systems to the dissemination of this therapy.

Cost-Benefit Analysis↗
PubMed2007

The ethical implications of stratifying by race in pharmacogenomics.

Many predict that pharmacogenomics is poised to deliver on the promises of the genomic revolution in ushering an era of personalized medicine. However, questions have emerged over whether the field will deliver a truly individualized medicine or if population-based therapies that build on conventional notions of racial biology will prevail. At the heart of this issue is the challenge of knowing which axes of stratification are appropriate in identifying population differences and to what extent is race and/or ethnicity an appropriate method of comparison in studies of genetic variation. These questions make plain that in addition to the development of technical tools to identify salient gene variants associated with drug response, serious consideration over how best to characterize populations in human genetic variation research must be given in order to realize the putative benefits of tailored therapeutics.

Biomedical Research↗
PubMedDate not supplied

Development of cholinergic amacrine cell stratification in the ferret retina and the effects of early excitotoxic ablation.

The present study has examined the emergence of cholinergic stratification within the developing inner plexiform layer (IPL), and the effect of ablating the cholinergic amacrine cells on the formation of other stratifications within the IPL. The population of cholinergic amacrine cells in the ferret's retina was identified as early as the day of birth, but their processes did not form discrete strata until the end of the first postnatal week. As development proceeded over the next five postnatal weeks, so the positioning of the cholinergic strata shifted within the IPL toward the outer border, indicative of the greater ingrowth and elaboration of processes within the innermost parts of the IPL. To examine whether these cholinergic strata play an instructive role upon the development of other stratifications which form within the IPL, one-week-old ferrets were treated with L-glutamate in an attempt to ablate the population of cholinergic amacrine cells. Such treatment was shown to be successful, eliminating all of the cholinergic amacrine cells as well as the alpha retinal ganglion cells in the central retina. The remaining ganglion cell classes as well as a few other retinal cell types were partially reduced, while other cell types were not affected, and neither retinal histology nor areal growth was compromised in these ferrets. Despite this early loss of the cholinergic amacrine cells, which are eliminated within 24 h, other stratifications within the IPL formed normally, as they do following early elimination of the entire ganglion cell population. While these cholinergic amacrine cells are present well before other cell types have differentiated, apparently neither they, nor the ganglion cells, play a role in determining the depth of stratification for other retinal cell types.

Aging↗
PubMed2006

Stratification of foot ulcer risk in patients with diabetes: a population-based study.

This trial assessed whether a simple clinical tool can be used to stratify patients with diabetes, according to risk of developing foot ulceration. This was a prospective, observational follow-up study of 3526 patients with diabetes (91% type 2 diabetes) attending for routine diabetes care. Mean age was 64.7 (range 15-101) years and duration of diabetes was 8.8 (+/-1.5 SD) years. Patients were categorised into 'low' (64%), 'moderate' (23%) or 'high' (13%) risk of developing foot ulcers by trained staff using five clinical criteria during routine patient care. During follow-up (1.7 years), 166 (4.7%) patients developed an ulcer. Foot ulceration was 83 times more common in high risk and six times more in moderate risk, compared with low-risk patients. The negative predictive value of a 'low-risk score' was 99.6% (99.5-99.7%; 95% confidence interval). This clinical tool accurately predicted foot ulceration in routine practice and could be used direct scarce podiatry resources towards those at greatest need.

Adolescent↗
PubMed2004

Asthma population management: development and validation of a practical 3-level risk stratification scheme.

OBJECTIVE: To define and validate a practical risk stratification scheme based on administrative data for use in identifying patients at high, medium, and low risk of requiring emergency hospital care for asthma. STUDY DESIGN: Retrospective cohort. PATIENTS AND METHODS: Predictors in 1999 were evaluated in relation to 2000 asthma emergency hospital care (any asthma hospitalization or emergency department visit) in a training set (n = 8789, 2000 emergency hospital care = 5.5%) and a testing set (n = 6104, 2000 emergency hospital care = 7.9%). Logistic regression was used to assign risk points in the training set, and positive and negative predictive values, sensitivities, and specificities were calculated in the training and testing sets. RESULTS: High risk was defined as asthma emergency hospital care in the previous year or use of >14 beta-agonist canisters and oral corticosteroid use; medium risk was defined as no emergency hospital care but use of either >14 beta-agonist canisters or oral corticosteroids; and low risk was defined as none of the above. For the high-risk groups in the training and testing sets, positive predictive values were 12.9% and 22.0%, sensitivities were 24.8% and 25.4%, specificities were 90.3% and 92.0%, and negative predictive values were 95.4% and 93.2%, respectively. The medium-risk groups identified another 32.6% of patients in the training set and 28.3% in the testing set requiring subsequent asthma emergency hospital care. CONCLUSION: This simple risk stratification scheme is useful for identifying patients from administrative data who are at increased risk of experiencing emergency hospital care for asthma.

Adolescent↗
PubMed2004

Screening potential elderly preferred markers: exploratory analysis of Cardiovascular Health Study (CHS) data.

The Cardiovascular Health Study (CHS) analyzes risk factors for coronary heart disease and stroke in people age 65 and older. Since CHS is designed to comprehensively study cardiovascular risk factors in an elderly population, it provides a unique opportunity to study the association of risk factors with mortality, as well as morbidity risk. With the growth of the elderly as population and life insurance market segments, the need to more precisely stratify mortality within a standard risk group of the elderly has grown as well. This exploratory analysis assesses medical factors that could be used to improve mortality risk stratification within a "standard" mortality population, using the CHS public use data set. Participants with a personal history of cardiovascular disease, diabetes, or major electrocardiographic abnormalities were excluded from the analysis in order to mimic a standard life insurance selection process. Then, Cox proportional hazards regression was used to study 10 medical risk factors. This model suggested that forced vital capacity >80% predicted, serum creatinine <1.5 mg/dL (133 mcmol/L), hemoglobin >11 g/dL (110 g/L), and serum albumin >3.5 mg/L (35 mmol/ L) are significantly associated (p = 0.05) with favorable mortality. C-reactive protein <1 mg/L is associated with favorable mortality at borderline significance levels (p = 0.09). On the other hand, a family history of cardiovascular disease (MI and/or stroke) and low BMI (<26 kg/m2) are associated with unfavorable mortality in the analysis. Total to HDL cholesterol ratio of <6, presence of supine systolic blood pressure < or = 140 mmHg, and the presence of minor rest electrocardiographic findings were not statistically significant factors in the multivariate model. Further assessment of the predictive value of the "significant" medical factors identified is required in insured lives.

Aged↗
PubMed1999

Outcome analysis of coronary artery bypass grafting: minimally invasive versus standard techniques.

Minimally invasive coronary artery bypass grafting (MIDCAB) procedures are purported to result in improvements in patient management over standard techniques. A comparative study was performed on risk-stratified patients treated with either technique. Following institutional review board approval, a retrospective random chart review was conducted on 27 MIDCAB and 37 standard coronary artery bypass grafting (CABG) patients who were operated on over a 12-month period at the University of Nebraska Medical Center. Risk stratification was accomplished by dividing the two patient populations, MIDCAB and 'standard', into one of four subgroups based on a preoperative risk score. Risk stratification was achieved by dividing the patient populations into one of four subgroups: good, fair, poor and high risk. Both groups received similar operations and surgical interventions, except for the inclusion of cardiopulmonary bypass (CPB). Approximately 200 parameters were collected and analyzed in the following categories: anthropometric, operative and postoperative outcomes. The MIDCAB group had a significantly lower number of vessels bypassed (2.0+/-0.7 vs 3.4+/-0.9, p < 0.0001). Total postoperative blood product transfusions trended higher in the standard group (6.1+/-12.6 U) when compared to the MIDCAB patients (2.3+/-5.5 U, p < 0.15), although not statistically significant. Postoperative inotrope use was significantly less in the MIDCAB group (19% vs 59%, p < 0.002). Ventilator time in the MIDCAB group was 10.5+/-5.4 h vs 15.0+/-12.3 h in the standard group (p < 0.07). The MIDCAB group had an overall greater length of stay, but was only statistically different within the poor-risk subgroup (12.2+/-10.7 vs 7.5+/-3.9, p < 0.04). The results of this study show that when CPB is not utilized in treating patients undergoing CABG procedures, the benefits in regards to patient outcomes are unclear. This necessitates the need for further work when comparing outcomes for risk-stratified patients.

Aged↗