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PubMed2004

Specific ultrarush desensitization in Hymenoptera venom-allergic patients.

BACKGROUND: Hymenoptera venom hypersensitivity is an epidemiologically important problem. The only effective treatment in the management of venom-allergic patients with a history of generalized reactions to insect sting is specific immunotherapy. OBJECTIVE: To demonstrate safety and effectiveness of a modified ultrarush desensitization protocol in venom-allergic patients. METHODS: Fifty-seven patients with Hymenoptera venom allergy underwent a specific 1-day ultrarush desensitization by the subcutaneous route, reaching the cumulative dose of 101.1 microg in 2.5 hours. The maintenance dose (100 microg) was administered after 15 days and thereafter once a month. Patients were followed up for a year. Antihistamines were withheld for 15 days before and during desensitization to not underestimate the incidence of adverse effects. RESULTS: All patients but I completed the ultrarush desensitization. (This patient discontinued the treatment because of a hypertensive crisis not related to the desensitization.) The treatment caused a rapid variation of immunological parameters (IgE, IgG4) since the 15th day. After the desensitization, skin prick test results became negative in 15 patients (27%, decrease of 3.5 log), whereas they decreased in 14 patients (25%, decrease of 1 log). Sixty-four percent showed no adverse effects. Only 7% had a mild systemic reaction. CONCLUSIONS: Ultrarush desensitization is an effective and safe therapy in the management of patients with Hymenoptera venom allergy. In fact, it provides a faster tolerance, without significant differences regarding incidence of severe adverse effects, compared with traditional and rush protocols. It can be adopted for all patients, even children and teenagers.

Adolescent↗
PubMed2004

Strategies for disease modification in Alzheimer's disease.

Treating Alzheimer's disease (AD) is the biggest unmet medical need in neurology. Current drugs improve symptoms, but do not have profound disease-modifying effects. Three main classes of disease-modification approaches can be defined: one that is broadly neurotrophic or neuroprotective, one that targets specific aspects of AD pathology, and one that is based on epidemiological observation. This review discusses all three approaches, with particular emphasis on anti-amyloid strategies - currently the most active area of investigation. The approaches that are reviewed include secretase inhibition, amyloid-beta aggregation inhibition, immunotherapy and strategies that might indirectly affect the amyloid pathway.

Alzheimer Disease↗
PubMed2001

Prevention and treatment of cancer with indole-3-carbinol.

Indole-3-carbinol (I-3-C) is a naturally occurring constituent of many plant foods. Oral administration of I-3-C has been shown to manipulate estrogen metabolism in humans in a possibly beneficial manner. I-3-C increases the 2/16-hydroxyestrone ratio, a ratio found to be predictive of breast cancer risk in some prospective studies. Animal and in vitro studies have identified a number of other possibly beneficial effects of I-3-C and its metabolites, including inhibition of estrogen binding and modulation of oncogene expression. A chemopreventive effect of I-3-C has been demonstrated in a number of animal models. Some chemical carcinogenesis models have found a tumor promoting effect of I-3-C, however. Epidemiological studies support the hypothesis that high intakes of I-3-C may have broad chemopreventive effect. Preliminary human trials have demonstrated that I-3-C is well tolerated and has a sustained estrogen modifying effect. I-3-C is a good candidate for clinical trial in women at increased risk of developing breast cancer.

Animals↗
PubMed2002

[Fiber in the treatment of obesity and its comorbidities].

A considerable part of the health-care significance of obesity lies in its co-morbidity. Obesity is associated with high blood pressure, type 2 diabetes mellitus and dyslipidaemia, representing both individually and when taken together risk factors for cardiovascular disease, the main cause of death in industrialized countries. The influence of fibre consumption on body weight, the risk of type 2 diabetes and cardiovascular disease has been shown in important epidemiological surveys, but the mechanisms whereby fibre exercises this protective effect have not been definitively clarified. For the most part, the ability of fibre to slow down the process of absorption of nutrients by modifying the metabolic response to intake, its ability to increase the excretion of biliary acid and the metabolic effects of the short-chain fatty acids produced in the bacterial fermentation of fibre have all focussed the attention of the working hypotheses analyzed in the studies published in the last few years. This review is intended to identify the importance of fibre for the prevention and treatment of obesity and its comorbidities on the basis of the available evidence at present.

Cardiovascular Diseases↗
PubMed1976

Restriction and modification of Shigella flexneri phages by R factors.

Out of 420 R factors derived from Shigella flexneri strains, 50.8% restricted Escherichia coli and S. flexneri phages. Phage restriction was produced both by fi- and fi+ R factors. The R factors were divided into nine groups on the basis of the efficiency of plating of S. flexneri phages. Changes of phage types were produced by transferring R factors of different restrictive types. The changes offered some information concerning the evolution of phage types. Studies on phage modification supported the grouping of R factors determined on the basis of restriction. R factors of different restrictive types were type-specific except for types VII and IX. Modified phages proved to be highly practical for epidemiological purposes. The use of modified phages, as an additional phage-set besides that basic phage-set, was suggested to trace the source of strains which changed their phage types as an effect of R factors.

Bacteriophage Typing↗
PubMed1998

[Changes in female reproduction induced by ammonium metavanadate in Swiss albino mice].

Female reproduction alterations induced by vanadium salts, taken in periods no related with mating/gestation, correlated with histological alterations has not been reported. Vanadium is a metal from VB group of periodical table, and it has been detected in high concentrations in heavy petroleum produced in this region of our country, there have not had investigations about vanadium effect on species reproduction. In this work 100 and 200 ppm doses of ammonium vanadate (A.M.V.) prepared with demineralized water were administered orally to swiss albino mice in different periods. The administration of vanadium salt was suspended before mating. Pregnant mice were allowed to deliver and a statistical analysis were performed to pregnancy percent and pups means. Non pregnant mice were killed after 21 days of mating. Uterus and ovaries were weight, luteal bodies were counted and histological samples of ovaries were prepared. The results shown a non significative increase of pregnancy (p < 1) in mice exposed from weaning to adult, for animals exposed to maximum concentrations 200 ppm a significative reduction of pregnancy (p = 0.00001), to mean pups were detected (z = 0.68), and number of luteal bodies (s = 3.3 +/- 0.5). The microscopic observation shown polycystic ovary, atresic follicular increasing, follicle in mature stage and luteal bodies; hard decreasing; hard depletion was observed in thecoluteic cells of luteal bodies. A.M.V. modify reproduction even though if exposition have been made in period before mating and pregnancy. As doses and exposition periods increase detrimental effects induces alteration in the follicular phase and luteal of ovarian cycle. Epidemiological and genetic studies are recommended in regions where vanadium concentrations are high, and the drinking water and foods are contaminated with this metal, in order to know how it affect human reproduction.

Administration, Oral↗
PubMed1998

In-vitro effect of oncostatin M on the release by endothelial cells of von Willebrand factor, tissue-type plasminogen activator and plasminogen activator inhibitor-1.

Epidemiological studies have demonstrated that levels of plasma fibrinogen, von Willebrand factor (vWf), plasminogen activator inhibitor-1 (PAI-1) and tissue-type plasminogen activator (tPA) are associated with the incidence of vascular disease. Since oncostatin M dramatically induces fibrinogen biosynthesis by hepatocytes and could be implicated in vascular injury leading to atherosclerosis, we have analyzed the effect of oncostatin M on PAI-1, vWf and tPA secretion by endothelial cells. A 2-h incubation of human umbilical vein endothelial cells with oncostatin M increases thrombin-induced secretion of vWf to the same extent as tumour necrosis factor-alpha or interleukin-1 (137+/-26% of control for 5 ng/ml oncostatin M, P < 0.001, n=5). The effects on tPA and PAI-1 secretion were different depending on the type of endothelial cells tested. On human umbilical vein endothelial cells, oncostatin M induced an increase in PAI-1 and a decrease in tPA secretion, which could explain the thrombogenicity of oncostatin M on large vessels. On a human microvasculature endothelial cell line, oncostatin M did not modify PAI-1 but induced an increase in tPA secretion. This observation of the effects of oncostatin M on both macro- and microvasculature could explain the increased levels of vWf, PAI-1 and tPA in the plasma of atherosclerotic subjects identified in epidemiological studies, suggesting that oncostatin M could play a key role in the development of atherosclerotic lesions.

Arteriosclerosis↗
PubMed2006

Genotypic diversity and epidemiology of high-level gentamicin resistant Enterococcus in a Chinese hospital.

OBJECTIVE: To investigate the antibiotics resistance of Enterococcus, the aminoglycoside-modifying enzymes (AME) and homology of high-level gentamicin resistant (HLGR) Enterococcus in clinical specimens for the implementation of effective infection control measures. METHODS: The resistance of 13 antimicrobial agents was determined by Kirby-Bauer (K-B) or agar dilution method. And the HLGR and high-level streptomycin resistant (HLSR) isolates were screened by agar screen. Production of beta-lactamases was tested by the nitrocefin disc method. The aminoglycoside-modifying enzyme genes were detected by polymerase chain reaction (PCR). Pulsed-field gel electrophoresis (PFGE) was used to analyze the homology of HLGR isolates from in-patients. RESULTS: No isolates resistant to linezolid, vancomycin and teicoplanin were found. Ampicillin-resistant isolates did not produce beta-lactamases and 68 HLGR isolates were screened at the rate of 64.2%. The positive rate of aac(6')-Ie-aph(2'')-Ia was 86.8% and 3 isolates had the new AME gene designated aph(2'')-Ie mostly similar to aph(2'')-Id. Among 51 HLGR isolates from in-patients, PFGE grouped 17 Enterococcus faecalis (E. faecalis) isolates into 4 clusters (A-D), and 33 Enterococcus faecium (E. faecium) isolates into 8 clusters (A-H), of which the A cluster is the main. CONCLUSIONS: HLGR has become the important antibiotic resistance pathogen causing nocosomial infection. And the aac(6')-Ie-aph(2'')-Ia gene was the main aminoglycoside-modifying enzyme gene leading to HLGR.

Acetyltransferases↗
PubMed1999

Strategic issues in the design and interpretation of studies on metabolic polymorphisms and cancer.

This chapter describes in a simple way the most important issues of epidemiological design, with emphasis on studies on metabolic polymorphisms. Different options are offered to the researcher who approaches a molecular epidemiology study. Case-control studies and cohort studies have different and sometimes complementary advantages and disadvantages. The sources of bias and the choice of controls, with specific problems in the context of investigations on metabolic polymorphisms, are key issues. Confounding is an issue that needs further clarification in the field, partly because of the lack of complete biological knowledge on the complex relationships between exposure, markers of susceptibility, and cancer. Metabolic polymorphisms are correctly interpreted as effect modifiers of the exposure-disease relationship. This interpretation implies that studies should be planned in order to have sufficient statistical power and that an interactive term should be modelled in the statistical analysis.

Bias↗
PubMed1992

A modeling perspective on the culture of driving.

Each driver is influenced by the collective behavior of other drivers. At the same time, each driver is also part of this collective, and thus influences others. Underlying many driver control and traffic safety programs are two implicit and related assumptions: that drivers are sensitive to the "culture of driving" around them and emulate it; and, that a small shift in the behavior of few might be amplified or snowball to a much larger effect resulting in a changed traffic environment or a modified culture of driving. The paper discusses possible mechanisms for the interactions between individuals, collectives, and culture, drawing on literature from social psychology, sociology, economics, communication, epidemiology, and other disciplines. Traffic behavior modeling could benefit from considering concepts developed in other social disciplines while providing challenging research issues and data sources for testing and developing those concepts.

Automobile Driving↗
PubMed1998

Identifying patient populations at high risk for stroke.

Although the treatment of acute ischemic stroke has improved, the greatest reductions in stroke mortality and morbidity may possibly be achieved through more effective prevention strategies. Toward this goal, risk factor profiles for initial and recurrent stroke have been identified through longitudinal epidemiologic studies. Nonmodifiable risk markers for initial ischemic stroke include age, sex, family history, and race/ethnicity. Modifiable risk factors for first ischemic stroke include hypertension, cardiac disease (particularly atrial fibrillation), diabetes, hyperlipidemia, cigarette smoking, alcohol abuse, physical inactivity, asymptomatic carotid stenosis, and transient ischemic attack. As improved acute treatments increase survival after a first stroke, the threat of increased morbidity from stroke recurrence will have greater significance. The risk and specific determinants of early and late stroke recurrence are the subject of ongoing investigations. Age, stroke syndrome, hypertension, cardiac disease (particularly congestive heart failure), hyperglycemia, and alcohol abuse have been identified as predictors of late stroke recurrence. Now that many risk factors are established, greater emphasis should be placed on identifying high stroke-risk patient populations for intensive risk factor modification and antithrombotic treatments. Better understanding and management of stroke risk factors will undoubtedly improve our ability to prevent first and recurrent ischemic stroke.

Brain Ischemia↗
PubMed2000

Applied pharmacoeconomics: modeling data from internal and external sources.

The use and application of techniques for modeling data obtained from various data sources are discussed. Modeling with internal and external data has become a popular way for health care organizations to apply pharmacoeconomics to pharmacy practice. Modeling studies use existing clinical and epidemiologic data to project the effect of a clinical, policy, or medication decision on a patient, population, or organization. Although several modeling techniques have been used in health care, the most common approaches are to modify and adapt existing models or to develop a unique model to answer questions of interest in a specific practice setting. Typically, an economic model developed by adapting an existing one will use either the clinical decision-analysis or Markov modeling technique. Regardless of the technique used, external data must be carefully evaluated to ensure that the data are appropriate for use in making decisions at a specific organization. For example, cost data must be analyzed to ensure that the calculations are reproducible. Also, it must be acknowledged that this strategy may not always be appropriate. The use of modeling techniques can assist decision-makers in making more informed clinical, policy, and medication decisions in real-world settings. Caution is required when adapting and interpreting existing models to ensure appropriate application in a specific organization.

Algorithms↗
PubMed2002

Interactive effect of chemical substances and occupational electromagnetic field exposure on the risk of gliomas and meningiomas in Swedish men.

The objective of our study was to investigate the possible interactive effect of occupational exposure to extremely low-frequency magnetic field (ELFMF) and to known or suspected carcinogenic chemicals on the incidence of the two main histological types of brain cancer, gliomas and meningiomas, in a cohort of male Swedish workers. The historical cohort of all Swedish men gainfully employed in 1970 were followed 19 years (1971-1989). Exposure to ELFMF and to nine chemicals were assessed using two Swedish job exposure matrices based on occupational codes and industrial activity. Relative risks adjusted for age, period, geographical area, and town size were computed using log-linear Poisson models. The main finding was the absence of ELFMF effect on glioma risk in the absence of a simultaneous exposure to chemical products. The effect of petroleum products was independent of the intensity of ELFMF exposure whereas solvents, lead, and pesticides/herbicides were only associated with glioma in workers also exposed to moderate or high levels of ELFMF. On the other hand, whereas ELFMF seemed to enhance the effect of specific chemicals in the causation of gliomas, we did not find a relationship between ELFMF exposure and meningiomas. The potential for ELFMF to act as an effect modifier of the association of chemical agents and glioma is an interesting new finding. It would be worthwhile to evaluate this hypothesis for other tumors. Also, it is necessary to confirm these results in epidemiological studies with individual exposure assessments, and in experimental studies that may elucidate whether there is a true causal mechanism for the results we observed.

Adult↗
PubMed1986

Periodontal health and periodontal disease in young people: global epidemiology.

A review of epidemiological surveys of the periodontal conditions of young people has shown that chronic marginal gingivitis associated primarily with plaque, is global, very common and even endemic in some population groups. Data on the prevalence of transient gingival conditions associated with tooth eruption, puberty and systemic factors are lacking and therefore their contribution to the prevalence of periodontal disease is unknown. Reports of periodontitis in young people are relatively uncommon except in a few populations where it appears as an adult-type of chronic marginal periodontitis. Juvenile periodontitis and other more destructive forms of periodontitis are not common. However, problems in epidemiological methodology and clinical differential diagnosis make comparative evaluation of survey data difficult and subjective. Two epidemiological indices, the Periodontal Index and the Community Periodontal Index of Treatment Needs (CPITN) have been used for many surveys in varied population groups. They provide data which agree on the ubiquity of gingivitis, whether identified visually or by bleeding-on-probing, and the low frequency of periodontitis. Data from CPITN surveys reveal a higher prevalence of calculus (sub-gingival) associated with gingivitis in young people than previously reported. All the epidemiological data reviewed point to plaque as the primary aetiological agent in gingivitis. There is little evidence of the involvement of other factors except that host resistance/susceptibility in this age group may modify the microbial effect.

Adolescent↗
PubMed1980

Vaccination against poliomyelitis in economically underdeveloped countries.

Poliomyelitis lameness surveys in children of school age recently reported from Burma, Egypt, Ghana, and the Philippines have indicated an estimated, average annual endemic incidence of paralytic poliomyelitis similar to or higher than the overall average annual rate in the USA during the peak years in the prevaccine era. Contrary to oft-expressed dogma, high rates of paralytic poliomyelitis are occurring annually in regions with high infant mortality rates, continuing undernutrition, and absence of basic sanitary facilities. Recent data indicate that prolonged breast feeding does not impede the effectiveness of oral poliovirus vaccine (OPV). A high prevalence of nonpoliovirus enteric infections can modify, delay, and lower the frequency of seroconversion after OPV, but these effects are overcome by multiple doses. The problem of eliminating paralytic poliomyelitis from economically underdeveloped countries depends on administrative rather than immunological or epidemiological factors, although a specially concentrated effort is needed in countries where most of the cases occur during the first two years of life and where paralytic polioviruses are propagating throughout the year in a large proportion of the infant population. Under such circumstances, expanded routine infant immunization programmes, which include OPV but reach at best only 20-40% of the total infant population, who receive only one or a few doses of vaccines requiring multiple doses, cannot be expected to eliminate paralytic poliomyelitis as an important public health problem. Injections of multiple doses of quadruple vaccine (DPT + inactivated poliomyelitis vaccine) would not only greatly increase the cost of routine immunizations but would not achieve more or as much as feeding OPV at the time of the DPT injections. Mass administration of OPV each year on 2 days of the year 2 months apart, to all children under 2, 3, or 4 years of age (depending on the epidemiological situation), without reference to the number of OPV doses they may have had before, can be expected to yield optimum results in countries with small numbers of professional health personnel and many other year-round problems.

Child↗
PubMedDate not supplied

A method of analysis of laboratory data in an epidemiological study where time trends are present.

Where data are collected over an extended period, in either cross-sectional or prospective studies, time trends in laboratory measurements can have misleading effects on observed associations, especially where it has not been possible to randomize the order of entry of participants to the study. In an ongoing prospective study of ischaemic heart disease, a modified cusum technique is used to examine the data for time trends. The paper considers a method for estimating where changes may have occurred, a method for adjusting for such changes in investigating the associations between variables and the appropriateness of making such adjustments.

Adenosine Diphosphate↗
PubMed2003

Prenatal exposure to nicotine modifies kidney weight and blood pressure in genetically susceptible rats: a case of gene-environment interaction.

BACKGROUND: Epidemiologic studies suggest that in utero exposure to maternal smoking is associated with elevated blood pressure (BP) later in life. Our aims were: (1) to examine effects of intrauterine exposure to nicotine on BP and hypertension target-organ size in rats; and (2) to investigate whether such effects depend on genetic background, by studying two genetically distinct strains of rats: the spontaneously hypertensive rat (SHR) and the normotensive Brown Norway (BN) rat. METHODS: Nicotine or saline was administered to dams via subcutaneous osmotic minipumps throughout gestation. In nine-week-old male offspring, we measured BP and heart rate, assessed the weight of kidneys and heart, and determined fasting levels of glucose, insulin, triglycerides (TG), and cholesterol. We also measured gene expression of the insulin-like growth factor (IGF) system in the liver and kidneys. RESULTS: SHR and BN offspring differed in their response to intrauterine exposure to nicotine. SHR exposed to nicotine (vs. saline) exhibited higher BP (P < 0.02) and serum cholesterol levels (P = 0.01), and lower kidney weight (P < 0.0001). In contrast, BN rats did not demonstrate differences between the nicotine and saline groups in these variables, but the nicotine-exposed BN rats showed a significant up-regulation in the gene expression of IGF-1 in the liver (P < 0.0001) and IGF receptor in the kidney (P = 0.006). CONCLUSION: These results suggest that intrauterine exposure to nicotine alters the cardiovascular system depending on the genetic background and, as such, supports the notion that the intrauterine environment interacts with genes in determining an individual's health later in life.

Animals↗
PubMed2005

The association between stress and drinking: modifying effects of gender and vulnerability.

AIMS: To assess the relationship between number and type of past-year stressful experiences and alcohol consumption, with a focus on how gender, poverty, and psychological vulnerability moderate this association. METHODS: Data from 26 946 US past-year drinkers 18 years of age and over, interviewed in the 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), were used to construct multivariate linear regression models predicting six measures of drinking pattern and volume. RESULTS: There was a consistent positive relationship between number of past-year stressors experienced and all measures of heavy drinking. Frequency of heavy (5+ drinks for men; 4+ drinks for women) drinking increased by 24% with each additional stressor reported by men and by 13% with each additional stressor reported by women. In contrast, the frequency of moderate drinking (<5 drinks for men; <4 drinks for women) decreased as stress levels increased. Job-related and legal sources of stress were more strongly associated with alcohol consumption than were social and health-related stress. Men showed a stronger association than women between the number of stressors and the most consumption measures; they also responded more strongly to the presence of any legal and job-related stress. Having an income below the poverty level intensified the effects of job-related stress, but having a mood or anxiety disorder did not affect any of the associations between stress and consumption. CONCLUSIONS: Stress does not so much lead individuals to drink more often as to substitute larger quantities of alcohol on the days when they do drink. Treatment and brief interventions aimed at problem drinkers might benefit from addressing the issue of tension alleviation and the development of alternative coping mechanisms.

Adaptation, Psychological↗