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At least 433 records · Page 24Linked to original sources
PubMed2002

N-terminal pro brain natriuretic peptide on admission for early risk stratification of patients with chest pain and no ST-segment elevation.

OBJECTIVES: The study evaluated the prognostic value of single measurement of N-terminal pro brain natriuretic peptide (NT-proBNP) obtained on admission in patients with symptoms suggestive of an acute coronary syndrome and no ST-segment elevation. BACKGROUND: Patients with symptoms suggestive of an acute coronary syndrome and no ST-segment elevation constitute a large and heterogeneous population. Early risk stratification has been based on clinical background factors, electrocardiography (ECG) and biochemical markers of myocardial damage. The neurohormonal activation has, so far, received less attention. METHODS: The NT-proBNP was analyzed on admission in 755 patients admitted because of chest pain and no ST-segment elevation. Patients were followed concerning death for 40 months (median). RESULTS: The median NT-proBNP level was 400 (111 to 1646) ng/l. Compared to the lowest quartile, patients in the second, third and fourth quartiles had a relative risk of subsequent death of 4.2 (1.6 to 11.1), 10.7 (4.2 to 26.8) and 26.6 (10.8 to 65.5), respectively. When NT-proBNP was added to a Cox regression model including clinical background factors, ECG and troponin T, the NT-proBNP levels were independently associated with prognosis. CONCLUSIONS: A single measurement of NT-proBNP on admission will substantially improve the early risk stratification of patients with symptoms suggestive of an acute coronary syndrome and no ST-segment elevation. A combination of clinical background factors, ECG, troponin T and NT-proBNP obtained on admission will provide a highly discerning tool for risk stratification and further clinical decisions.

Aged↗
PubMed1992

[Social conditions of hemophiliacs].

The objects of this investigation were 1. to describe the social conditions of haemophiliacs by means of questionnaires and to compare these with the population as a whole and 2. to investigate the social integration of haemophiliacs as assessed by type of family, occupation, club membership and contact with family and friends. The group investigated consisted of all Danish haemophiliacs with moderate to severe factor VIII and IX deficiency and cases of severe von Willebrand's disease. 64% replied (n = 135). Comparison by the age stratification with the population as a whole, showed that fewer haemophiliacs in the age group 25-44 years lived with partners and children and that more lived with their parents or alone. Haemophiliacs had a higher school education and more haemophiliacs were currently receiving occupational training. The occupational frequency was low for all age groups and more haemophiliacs had reduced working hours. The frequencies of contact with friends and family and access to practical assistance corresponded to that of the population as a whole. Social integration was correlated directly with school education and occupational training and satisfaction with contact with other people and inversely correlated with age, contact with social welfare offices and number of social payments received. Only a total of 6% of haemophiliacs were very poorly socially integrated.

Adolescent↗
PubMed2006

Association of phosphodiesterase 4D polymorphisms with ischemic stroke in a US population stratified by hypertension status.

BACKGROUND AND PURPOSE: Phosphodiesterase 4D (PDE4D) underlies the STRK1 linkage peak for stroke on chromosome 5q12 identified in Iceland. We tested association of 13 single-nucleotide polymorphisms (SNPs) and 1 microsatellite in a nested case-control sample of elderly white women (>65 years of age) from the Study of Osteoporotic Fractures (SOF) in the United States. METHODS: The genotypes of 248 women who experienced an incident ischemic stroke during an average of 5.4 years of follow-up were compared with 560 controls. RESULTS: Marginal associations with stroke (P<0.10) were found for 3 polymorphisms. Stratification of the population by hypertension markedly strengthened the association. SNPs 9 (hazard ratio [HR], 0.48; 95% CI, 0.26 to 0.91), 42 (HR, 1.73; 95% CI, 1.10 to 2.70), 219 (HR, 1.73; 95% CI, 1.13 to 2.64), and 220 (HR, 1.56; 95% CI, 1.05 to 2.32) showed significant association with stroke (P<0.05) under a dominant model in subjects without hypertension at baseline, and SNP 175 was significantly associated with stroke under an additive model (HR, 0.76; 95% CI, 0.59 to 0.98) in subjects with hypertension. Furthermore, the microsatellite AC008818-1 showed association with stroke only in the nonhypertensive subjects. Based on results in Iceland, specific haplotypes were tested in SOF, and stratification by hypertension also affected these association results. CONCLUSIONS: These data are consistent with an association of the PDE4D gene with stroke in a non-Icelandic sample and suggest an effect of hypertension status.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1997

Assortative sexual mixing in a heterosexual clinic population--a limiting factor in HIV spread?

OBJECTIVE: To assess the degree of sexual mixing in a sexually transmitted disease clinic population stratified by country of birth. DESIGN: Prospective linked HIV serosurvey incorporating demographic and sexual risk data gathered by a doctor-administered questionnaire. SETTING: The Department of Genitourinary Medicine at St Thomas' Hospital, London, UK. SUBJECTS: Fifteen thousand eight hundred and seventy-eight heterosexuals who attended between April 1992 and February 1995. MAIN OUTCOME MEASURE: The degree of assortative (like-with-like) mixing, after stratification of the population by country of birth, of index patients, their parents and their sexual partners. RESULTS: Sexual mixing in this population of sexually transmitted disease clinic attenders is highly assortative when the CoB of parents (family origin) of index patients is taken into account. CONCLUSION: Our findings help to explain the low spread of heterosexual HIV infection in the UK to date, and may help future projections, and health targeting of those at risk. This model can be applied to other mixed population.

Ambulatory Care Facilities↗
PubMed2003

The associations of social class and social stratification with patterns of general and mental health in a Spanish population.

BACKGROUND: Social class, as a theoretical framework, represents a complementary approach to social stratification by introducing social relations of ownership and control over productive assets to the analysis of inequalities in economic, political, and cultural resources. In this study we examined whether measures of social class were able to explain and predict self-reported general and mental health over and above measures of social stratification. METHODS: We tested this using the Barcelona Health Interview Survey, a cross-sectional survey of 10 000 residents of the city's non-institutionalized population in 2000. We used Erik Olin Wright's indicators of social class position, based on ownership and control over productive assets. As measures of social stratification we used the Spanish version of the British Registrar General (BRG) classification, and education. Health-related variables included self-perceived health and mental health as measured by Goldberg's questionnaire. RESULTS: Among men, high level managers and supervisors reported better health than all other classes, including small business owners. Low-level supervisors reported worse mental health than high-level managers and non-managerial workers, giving support to Wright's contradictory class location hypothesis with regard to mental health. Social class indicators were less useful correlates of health and mental health among women. CONCLUSIONS: Our findings highlight the potential health consequences of social class positions defined by power relations within the labour process. They also confirm that social class taps into parts of the social variation in health that are not captured by conventional measures of social stratification and education.

Adolescent↗
PubMed2006

HIV infection and tobacco smoking behaviour: prospects for prevention? ANRS CO3 Aquitaine Cohort, 2002.

OBJECTIVE: To provide up-to-date and covariate-specific estimates on tobacco smoking prevalence in a representative cohort of French human immunodeficiency virus (HIV) 1 infected patients in 2002. DESIGN: We conducted a cross-sectional analysis of the Aquitaine Cohort of HIV-infected patients. A logistic regression model was used to estimate associations between regular tobacco smoking and sex, age, HIV transmission categories, duration and immuno-virological status of HIV infection and duration of antiretroviral therapy. Smoking prevalence estimates were compared with the general French population values after stratification on age and sex. RESULTS: Among 2036 patients included in the analysis, 51% were regular smokers (95%CI 49-53). Smoking prevalence was significantly higher with younger age (OR 1.7 among those < or = 45 years of age), among injecting drug users (OR 4.3), among those whose infection was not controlled (OR 1.2) and those whose HIV infection had been diagnosed for > or = 5 years (OR 1.5). The main difference with the general population was the peak smoking prevalence among HIV-positive patients infected through injecting drug use. CONCLUSIONS: HIV-infected patients are highly exposed to tobacco smoking, which is implicated in multiple conditions occurring in the course of HIV infection. Adapted smoking cessation programmes should become one of the priorities of the medical care of HIV-infected individuals.

Adolescent↗
PubMed2006

Family-based designs in the age of large-scale gene-association studies.

Both population-based and family-based designs are commonly used in genetic association studies to locate genes that underlie complex diseases. The simplest version of the family-based design--the transmission disequilibrium test--is well known, but the numerous extensions that broaden its scope and power are less widely appreciated. Family-based designs have unique advantages over population-based designs, as they are robust against population admixture and stratification, allow both linkage and association to be tested for and offer a solution to the problem of model building. Furthermore, the fact that family-based designs contain both within- and between-family information has substantial benefits in terms of multiple-hypothesis testing, especially in the context of whole-genome association studies.

Case-Control Studies↗
PubMed1999

The modelled benefits of individualizing radiotherapy patients' dose using cellular radiosensitivity assays with inherent variability.

OBJECTIVE: To model the increases in local tumour control that may be achieved, without increasing normal tissue complications, by prescribing a patient's dose based on cellular radiosensitivity measured using an assay possessing inherent variability. METHOD: Patient populations with varying radiosensitivity were simulated, based on measured distributions among cancer patients of the surviving fraction of their fibroblasts given a dose of 2 Gy in vitro (SF2). The dose-response curve for complications in the population was assessed using a formula relating SF2 to normal tissue complication probability (NTCP), by summing the data for the individuals. This curve was similar to clinically-derived dose-response curves. The effect of individualizing the patients' doses was explored, based on individual radiosensitivities measured by SF2, so that every patient had the same low (5%) value of NTCP. RESULTS: It was found that a significant gain (up to around 30%) in tumour control probability (TCP) was predicted for the population when the doses were individualized using a predictive assay result strongly correlated with NTCP. A greater gain in TCP was predicted when each of the individuals were assumed to have a higher sensitivity and the distribution of radiosensitivity in the population was widened to compensate. The gain in TCP was less (around 20%) when considering less-sensitive patients and a narrower distribution of radiosensitivities. The effect of assay variability and other factors that could affect the predictive power of the assay was simulated. Assay variability and an imperfect correlation between in vitro cell survival and tissue complications, rapidly increased the NTCP for the population when treated with individualized doses. However the individualized doses could be reduced so that NTCP declined to an acceptable level, but in this case the TCP for the population also declined. For example, when the assay variability was half the true variability in SF2, the gain in TCP was reduced to around 6%. Also, the predicted gains in population TCP were higher if tumour and normal tissue radiosensitivity were assumed to be correlated. In this case, and in the absence of assay variability, increases in population TCP of about 50% and 30% were predicted, depending on the assumed relative sensitivities of the individual patients compared with that of the population average. For practical application, the division of the patient population simply into three groups of high, average and low radiosensitivity was also examined. The three groups were treated with different doses and the NTCP for the population was kept below 5%. Although the gain in population TCP was less than that predicted with the full individualization, considerable gains of up to 20% were still predicted. This method of dividing the population was more resilient to assay variability and other factors that may affect complications in patients. The modelling suggests that small improvements in TCP (5-10%) may still be achievable even if the correlation between SF2 and late complications is lower at around - 0.4 to - 0.6, as reported in some clinical series. CONCLUSION: Modelling based on measured distributions of fibroblast radiosensitivity shows that improvements in tumour control rates may be achievable through the individualization of radiotherapy dose prescriptions of cancer patients, when assay variability is less than about 50% of the true variability in radiosensitivity, and with greater benefits if tumour and normal tissue radiosensitivity are correlated. Tripartite stratification of the population proved to be less sensitive to assay uncertainty, and can provide most of the benefits of the full individualization.

Algorithms↗
PubMed2002

Estimated prevalence of immunity to poliomyelitis in the city of São Paulo, Brazil: a population-based survey.

Objectives. Estimate the prevalence of immunity to poliomyelitis (anti-polio antibodies) in the city of São Paulo/Brazil through a population-based survey. Methods. A quantitative and inductive method was used to draw a representative sample of the population. Randomization and stratification (based on sex, age and residence region) was done, and 1,059 individuals were studied on a home-visit basis (structured questionnaires and blood samples). A microneutralization test was performed to detect anti-polio antibodies against serotypes 1, 2 and 3. Results. The estimated prevalence of immunity to poliomyelitis was high, with 94.6% prevalence of anti-polio 1 antibodies, 98.8% anti-polio 2 and 91.9% anti-polio 3. Despite this high prevalence, there were significantly lower prevalence levels in some groups, specially among age and residence region groups. Discussion. Routine child immunization and NIDs with OPV have provided excellent levels of serological immunity to poliomyelitis in the population of the city of São Paulo, Brazil. However, there may be specific groups with a lower prevalence of immunity. Estimations of the prevalence of immunity to poliomyelitis were made in a population-based survey, which could be used as an auxiliary tool for supporting the polio eradication program.

Adolescent↗
PubMed2006

A cluster of parvovirus B19 infections in renal transplant recipients: a prospective case series and review of the literature.

Up to 9% of renal transplant recipients have severe multifactorial erythropoietin-resistant anemia. Human parvovirus B19 (PVB19) infection can cause severe anemia and is likely underreported. Sparse information on epidemiology and management in this population exists. To address these issues, after our first index case, we modified our clinical practice to prospectively screen patients with persistent hemoglobin (Hb) <10 mg/dL for PVB19 infection after excluding common causes of anemia including erythropoietin resistance. Potentially infected patients were further evaluated by serology, qualitative polymerase chain reaction (quPCR) and bone marrow biopsy (BMB) for cytomegalovirus, Epstein-Barr virus, PVB19 and other etiologies. Over 3 months, 212 kidney recipients visited outpatient clinics. Of 52 recipients with anemia, 8 had an Hb <10 mg/dL with erythropoietin resistance and were screened for PVB19 infection. Three cases had PVB19 infection by quPCR and often-inconclusive serology/BMB results. Cases had immunosuppression reduced and received IVIG (0.5 gm/kg x 4 doses) with recovery from anemia, viral clearance in two cases and one recurrence. PVB19-mediated anemia occurred in up to three out of eight (38%) screened kidney recipients with Hb <10 mg/dL resistant to erythrypoietin. We recommend prospective risk stratification for this population, high indices of suspicion using at least qualitative techniques for diagnosis and treatment goal for viral eradication.

Adult↗
PubMed1996

16S rRNA genes reveal stratified open ocean bacterioplankton populations related to the Green Non-Sulfur bacteria.

Microorganisms play an important role in the biogeochemistry of the ocean surface layer, but spatial and temporal structures in the distributions of specific bacterioplankton species are largely unexplored, with the exceptions of those organisms that can be detected by either autofluorescence or culture methods. The use of rRNA genes as genetic markers provides a tool by which patterns in the growth, distribution, and activity of abundant bacterioplankton species can be studied regardless of the ease with which they can be cultured. Here we report an unusual cluster of related 16S rRNA genes (SAR202, SAR263, SAR279, SAR287, SAR293, SAR307) cloned from seawater collected at 250 m in the Sargasso Sea in August 1991, when the water column was highly stratified and the deep chlorophyll maximum was located at a depth of 120 m. Phylogenetic analysis and an unusual 15-bp deletion confirmed that the genes were related to the Green Non-Sulfur phylum of the domain Bacteria. This is the first evidence that representatives of this phylum occur in the open ocean. Oligonucleotide probes were used to examine the distribution of the SAR202 gene cluster in vertical profiles (0-250 m) from the Atlantic and Pacific Oceans, and in discrete (monthly) time series (O and 200 m) (over 30 consecutive months in the Western Sargasso Sea. The data provide robust statistical support for the conclusion that the SAR202 gene cluster is proportionately most abundant at the lower boundary of the deep chlorophyll maximum (P = 2.33 x 10(-5)). These results suggest that previously unsuspected stratification of microbial populations may be a significant factor in the ecology of the ocean surface layer.

Animals↗
PubMed2006

Microvolt t-wave alternans with exercise in pediatrics and congenital heart disease: limitations and predictive value.

BACKGROUND: Microvolt t-wave alternans (TWA) in early exercise is a noninvasive marker of life-threatening ventricular arrhythmia in some adult cardiac populations. The incidence and potential significance of sustained TWA in pediatric and congenital heart disease (CHD) populations has not been well defined. METHODS: TWA treadmill exercise studies in pediatric patients with CHD, myopathy, potential myocardial ischemia, syncope, or history of cardiac arrest were analyzed. Tests were categorized as abnormal for sustained TWA with onset heart rate < 130 beats/min with specific analyses for lower onset heart rates. Patient characteristics were analyzed as possible correlates of TWA. RESULTS: Over 2 years, 318 consecutive TWA exercise studies were performed in 304 patients (60% male, median 14 years, 6-41) for indications of syncope, cardiac arrest, possible ventricular arrhythmia, or evaluation of functional myocardial perfusion. Underlying conditions included apparently normal hearts (45%), CHD (16%), cardiomyopathy (11%), coronary anomalies (11%), electrical myopathy (9%), and transplant (8%). Abnormal TWA was seen in 24 (7%, onset HR 106 +/- 18) and included 19 at high clinical risk for serious events including 3 with cardiac arrest. By multivariate analysis sustained TWA was associated with cardiac arrest, ventricular arrhythmias, and a clinical classification of high risk. CONCLUSIONS: TWA is associated with pediatric and CHD diagnoses at high risk of serious events and may contribute, with other diagnostic tools, to management choices. While the absence of TWA has relatively high negative predictive value, it does not completely exclude the potential for serious sustained ventricular arrhythmias. A more robust noninvasive marker for risk stratification in these populations is required.

Adolescent↗
PubMed1993

Prognostic value of karyometric and clinical characteristics in renal cell carcinoma. Quantitative assessment of tumor heterogeneity.

BACKGROUND: The variation in tumor cell differentiation within one renal cell carcinoma, also termed tumor heterogeneity, renders visual tumor grading of these carcinomas difficult. Karyometric analysis enables description of nuclear characteristics of multiple tumor areas. Hence, karyometric analysis can be used to quantify tumor heterogeneity and thus may aid in a more objective grading of renal cell carcinoma. METHODS: In 121 patients with renal cell carcinoma (tumors in International Union Against Cancer [UICC] stages I [5 cases], II [23 cases], III [33 cases], and IV [60 cases]), clinical and karyometric features were studied to obtain routinely applicable prognostic factors. Several parts of the tumor were analyzed to obtain a measure of tumor heterogeneity. Univariate and multivariate Cox regression analyses were used to determine the predictive value of karyometric features independent of tumor stage and other clinical characteristics. RESULTS: The Cox univariate regression analysis showed correlation of several clinical and karyometric characteristics with survival. Of the clinical characteristics, TNM stage, tumor size, weight reduction, and performance status were significantly associated with survival. The karyometric features, especially those measurements associated with tumor heterogeneity (e.g. differences in nuclear size or chromatin texture between tumor subpopulations) were of value in predicting prognosis. In the Cox multivariate regression analysis, the Robson and UICC stages proved to be the most powerful predictors of survival (P < 0.0001). Of the clinical features, weight reduction and performance score were the only characteristics offering additional information regarding tumor stage (P < 0.0001). From the karyometric analysis quantification of anisokaryosis in the tumor at time of diagnosis offered additional prognostic information. Moreover, the differences of karyometric features within the tumor presumably associated with tumor heterogeneity correlated with survival. Using the features from the multivariate analysis, prognostic groups could be defined. CONCLUSION: We conclude that karyometric analysis offers a useful means for quantifying tumor heterogeneity. Multivariate Cox analysis revealed additional value of a grading system based on karyometric analysis to tumor stage. Karyometric analysis can be a useful tool for stratification of patient populations.

Adult↗
PubMed1998

[Value of the Hannover Intensive Score (HIS) in internal medicine intensive care].

BACKGROUND AND OBJECTIVES: Scoring systems are important tools for quality control and stratification of study populations in intensive care medicine. The study aims to systematically evaluate predictive ability and severity classification ability of the combined physiologic-therapeutic Hannover Intensiv Score (HIS). Such data are not existing regarding medical intensive care medicine. METHODS: 1060 consecutive patients (ICU stay > 4 hours) being admitted to a medical ICU were prospectively investigated. HIS was determined for all patients each day during ICU stay. The results were compared to the physiologically based APACHE II and to the therapeutically based TISS, which both were determined as well. RESULTS: HIS provided sufficient discrimination between survival and nonsurvival [hospital mortality; area under the ROC curve (AUC) = 0.822] with no significant differences compared to APACHE II (AUC = 0.838) and TISS (AUC = 0.798), respectively. During longer course of ICU stay HIS offers better outcome prognostication compared to the unilateral systems with respect to specificity and total correct classification rate. There was a nearly linear increase of hospital mortality with an increase of day-1-HIS. The same was observed with APACHE II and TISS. Mean day-1-scores for survivors were significantly higher compared to non-survivors with all systems (p < 0.0001). Day-1-HIS moderately correlates with both other systems (APACE II: r = 0.766; TISS: r = 0.814). CONCLUSIONS: The Hannover Intensiv Score as a model of a combined physiologic-therapeutic scoring system was successfully validated concerning hospital outcome prediction and severity of disease classification in a large medical ICU population. Thus, for these applications it can be used in similar German ICUs. A main argument for applying the system is the employment of a fairly small set of easily accessible parameters.

APACHE↗
PubMed2005

[Possible ways of managing cardiovascular prevention: polypharmacy, additional payment or application of evidence based medicine?].

The financial balance of the health care system has changed dramatically due to a longer life expectancy and improved treatment options in elderly patients. More than 80% of cardiovascular events are lifestyle related and potentially preventable. Lifestyle modification is therefore the causal approach to decrease cardiovascular events. Improvement of nutrition and activity habits and prevention of cigarette smoking should start in the kindergarten, school and later at the workplace. A co-operation between medical societies and government institutions is necessary to achieve a population wide modification of lifestyle habits to lower the incidence of cardiovascular events in the population. Individual risk stratification is the basis for pharmacological prevention of cardiovascular events. The concept of the polypill has to be tested in controlled randomised studies.

Cardiotonic Agents↗
PubMed2005

Minimal clinical benefit of single agent Orathecin (Rubitecan) in heavily pretreated metastatic breast cancer.

PURPOSE: The purpose of this phase II study was to evaluate the efficacy and tolerability of Orathecin, an oral camptothecin analog that has exhibited antitumor activity in breast cancer patients during preclinical studies. METHODS: Sixteen patients with metastatic breast cancer previously treated with anthracycline and taxane were utilized in the study. Orathecin was administered orally at 1.5 mg/m2 /day for the first five consecutive days of the cycle followed by 2 days of rest on a 7-day schedule. The end points of the study were efficacy and toxicity. RESULTS: The median age of the patients was 51 years (range, 35-73). Eight patients (50%) had multiple disease sites, and nine patients (56%) received more than three chemotherapy regimens. All patients were evaluated for toxicity, three patients were removed from the study for toxicity or disease progression prior to 8 weeks and were thus not evaluated for efficacy. The median follow-up was 110 days (range, 15-554). There were no responses to treatment. Five of the 13 evaluable patients (38%) had stable disease, eight (61%) had progressive disease. Most adverse events were mild to moderate in intensity. The median time to progression (TTP) for evaluable patients was 109 days (range, 56-374 days) (lower 95% C.I., 57 days). The median survival time was 272 days (lower 95% C.I., 209 days). CONCLUSIONS: Orathecin at the dose and regimen used in this study resulted in no objective tumor responses for this heavily pretreated population. Accurate risk stratification strategies can improve patients' selection and contribute to determine the appropriate benefit of therapies in MBC.

Adult↗
PubMed1999

No association between the HLA-A2 allele and Alzheimer disease.

The apolipoprotein E (APOE)-4 allele is a major risk factor for late-onset Alzheimer disease (AD), but it does not account for all the genetic variation in late-onset AD; thus, other genetic markers must be examined. Previous studies suggest an HLA-A2 allele association with risk and earlier onset age of AD. Because these effects may be additive to those of APOE-4, we studied HLA-A2 and APOE-4 frequencies in AD patients and cognitively intact controls. A total of 712 unrelated Caucasian subjects included 479 patients with AD (435 sporadic, 44 familial) and 233 controls. Patients (mean+/-SD age 73.9+/-7.9 years, range 42-93 years) had probable AD, according to standard diagnostic criteria; controls (mean+/-SD age 70.4+/-8.5 years, range 37-92 years) were cognitively intact. APOE and HLA-A2 typing used polymerase chain reaction to indicate the number of APOE-4 alleles present as well as the presence (A1/A2, A2/A2 genotypes) or absence (A1/A1 genotype) of HLA-A2. A two-way analysis of variance was used to assess the effect of the HLA-A2 allele on age at onset of dementia. No association between HLA-A2 and APOE-4 was found, and the presence of HLA-A2 allele did not increase AD risk. There was also no evidence for an association between HLA-A2 and earlier onset age of AD. Examination age, sex, family history of AD, and recruitment site had no influence on these results. In conclusion, the HLA-A2 allele did not influence AD risk or onset age in this study population. A2 heterozygosity, and population differences, including stratification sub-structures, and other undetermined factors could contribute to discrepant findings among studies.

Adult↗
PubMedDate not supplied

Computer models of albumin and haemoglobin glycation.

UNLABELLED: Two first-order mathematical models were developed to mimic the glycation of haemoglobin (H) and albumin (A). The total concentrations of A and H were assumed to be constant. The responses of the two models to varying blood glucose level were compared. The parameters of the haemoglobin model were not numerically estimated, only an informal fit was performed using clinical and published data. Nonlinear regression analysis was used to estimate the parameters of the albumin model. The level of glycated A (GA) was derived from the measured fructosamine level. Three diabetics were monitored daily for the level of fructosamine and blood glucose profile over a period of 10, 16 and 21 days, respectively. CONCLUSIONS: (1) The difference between GA and glycated H (GH) resulting from different elimination rates is decreased by the stratification of erythrocyte population. (2) Both GA and GH seem to have higher elimination rates than their nonglycated equivalents.

Blood Glucose↗