Age-period-cohort modelling of type 1 diabetes incidence rates among children included in the EURODIAB 25-year follow-up study.

AIMS: Specific patterns in incidence may reveal environmental explanations for type 1 diabetes incidence. We aimed to study type 1 diabetes incidence in European childhood populations to assess whether an increase could be attributed to either period or cohort effects. METHODS: Nineteen EURODIAB centres provided single year incidence data for ages 0-14 in the 25-year period 1989-2013. Case counts and person years were classified by age, period and cohort (APC) in 1-year classes. APC Poisson regression models of rates were fitted using restricted cubic splines for age, period and cohort per centre and sex. Joint models were fitted for all centres and sexes, to find a parsimonious model. RESULTS: A total of 57,487 cases were included. In ten and seven of the 19 centres the APC models showed evidence of nonlinear cohort effects or period effects, respectively, in one or both sexes and indications of sex-specific age effects. Models showed a positive linear increase ranging from approximately 0.6 to 6.6%/year. Centres with low incidence rates showed the highest overall increase. A final joint model showed incidence peak at age 11.6 and 12.6 for girls and boys, respectively, and the rate-ratio was according to sex below 1 in ages 5-12. CONCLUSION: There was reasonable evidence for similar age-specific type 1 diabetes incidence rates across the EURODIAB population and peaks at a younger age for girls than boys. Cohort effects showed nonlinearity but varied between centres and the model did not contribute convincingly to identification of environmental causes of the increase.

A COMMENTARY ON CLASSIFICATION OF DIABETES: LATENT AUTOIMMUNE DIABETES IN ADULTS (LADA) OR INTERMEDIARY DIABETES MELLITUS (IDM)?

Diabetes Mellitus is a huge syndrome which can be detected from the first day of life until the last year of life of a centenarian. In the current classification of diabetes among the so-called "idiopathic phenotypes", apart Type 1 Diabetes (T1D) and Type 2 Diabetes (T2D) has been included provisionally term "Latent Autoimmune Diabetes in Adults" (LADA). This has unclear characterization regarding the age at onset, the presence of anti-ß-cell antibodies and the level of insulin secretory function, in conformity with C-peptide levels. According to several recent publications, there are no specific biochemical or genetic markers for Latent Autoimmune Diabetes in Adults (LADA), but only a gradual transition from T1D to T2D. In addition, the word "latent" in the construction of "LADA" term is inaccurate because in this phenotype nothing is latent: both the autoimmunity and diabetes are present and are even parts of the diagnosis. So that, the best term should be what in reality this sub-phenotype is: an Intermediary Diabetes Mellitus (IDM). Some recent genetic data strongly support this designation.

Decreased paraoxonase 2 enzymatic activity in monocyte/macrophages cells. A comparative in vivo and in vitro study for diabetes.

AIM: To investigate peripheral blood monocytes/macrophages (Mo/Mᴓ) paraoxonase 2 (PON2) in diabetes and the factors modulating its activity. METHODS: One hundred and eighteen patients with newly diagnosed uncomplicated type 2 diabetes mellitus were compared regarding clinical, biochemical and oxidative stress parameters with 80 healthy subjects. The capacity of the peripheral blood mononuclear cells (PBMNC) to release pro-oxidants and to neutralise them was determined by measuring the respiratory burst (RB) and the intracellular antioxidant enzyme PON2. In vitro experiments were conducted on a differentiated monocytes cell line (dU937) that was exposed to serum deprivation followed by addition of isolated lipoproteins (VLDL or LDL). RESULTS: Paraoxonase 2 activity in Mo/Mᴓ was significantly lower in type 2 diabetes patients (0.042 ± 0.044 vs 0.165 ± 0.133U lactonase activity/mg protein in controls, p < .0005) and decreased in the obese in all groups. It was inversely correlated to parameters of adiposity (BMI and Waist Circumference), of glucose control (blood glucose, fructosamine and HbA1c) and insulin resistance (HOMA-IR). In multivariate regression models, 15-34% of the PON2 variance was explained by diabetes. The in vitro addition of VLDL normalised the RB of serum deprived dU937 cells, S- (to 82 ± 18% of the cells incubated with serum, S+) and PON2 activity (from 0.524 ± 0.061 in S - to 0.298 ± 0.048 U/mg protein). In contrast, when LDL was added, the RB remained lower (61 ± 12% of S+, p = .03) and PON2 higher (0.580 ± 0.030 U/mg protein, p = .003). CONCLUSIONS: The decrease in monocyte/macrophage PON2 enzymatic activity observed in type 2 diabetes cannot be totally explained by abdominal obesity and insulin resistance. The underlying molecular mechanisms need to be identified.

Seasonal variation in month of diagnosis in children with type 1 diabetes registered in 23 European centers during 1989-2008: little short-term influence of sunshine hours or average temperature.

BACKGROUND: The month of diagnosis in childhood type 1 diabetes shows seasonal variation. OBJECTIVE: We describe the pattern and investigate if year-to-year irregularities are associated with meteorological factors using data from 50 000 children diagnosed under the age of 15 yr in 23 population-based European registries during 1989-2008. METHODS: Tests for seasonal variation in monthly counts aggregated over the 20 yr period were performed. Time series regression was used to investigate if sunshine hour and average temperature data were predictive of the 240 monthly diagnosis counts after taking account of seasonality and long term trends. RESULTS: Significant sinusoidal pattern was evident in all but two small centers with peaks in November to February and relative amplitudes ranging from ± 11 to ± 38% (median ± 17%). However, most centers showed significant departures from a sinusoidal pattern. Pooling results over centers, there was significant seasonal variation in each age-group at diagnosis, with least seasonal variation in those under 5 yr. Boys showed greater seasonal variation than girls, particularly those aged 10-14 yr. There were no differences in seasonal pattern between four 5-yr sub-periods. Departures from the sinusoidal trend in monthly diagnoses in the period were significantly associated with deviations from the norm in average temperature (0.8% reduction in diagnoses per 1 °C excess) but not with sunshine hours. CONCLUSIONS: Seasonality was consistently apparent throughout the period in all age-groups and both sexes, but girls and the under 5 s showed less marked variation. Neither sunshine hour nor average temperature data contributed in any substantial way to explaining departures from the sinusoidal pattern.

The dynamics of life expectancy over the last six decades in elderly people with diabetes.

AIM: To investigate the historical changes in survival with diabetes in elderly people with diabetes. RESEARCH DESIGN AND METHODS: We analyzed 6504 deaths (44.5% males) registered in a large urban population, aged ≥65 years, and deceased between 1943 and 2009. We split the analysis into three time periods according to year of death: 1943-1965, 1966-1988 and 1989-2009. The parallel changes in the corresponding general population were available. RESULTS: The mean age at diabetes onset was 70.8 ± 4.7 years, with mean disease duration at death 7.5 ± 5 years, and mean age at death 78.3 ± 5.9 years. The mean survival loss due to diabetes (expected minus observed survival) was 4.5 ± 5.1 years (4.9 ± 5.1 years for females versus 4.1 ± 5.2 years for males, p<0.001). The mean disease duration at death was 6.4 ± 5.7 years in the period 1943-1965, followed by a significant (p=0.019) rise to 7 ± 5 years in 1966-1988, and 8.3 ± 4.9 years (p<0.001) in 1989-2009. There was a significant increase in coronary heart disease and stroke, and a significant decrease in infections and end-stage renal disease as causes of death. CONCLUSIONS: We found a significant increase in age at onset and survival with diabetes leading to a significant increase in age at death. Females had a higher survival loss due to diabetes compared with males.

Increase in total antioxidant capacity of plasma despite high levels of oxidative stress in uncomplicated type 2 diabetes mellitus.

OBJECTIVE: Oxidative stress is implicated in the pathophysiology of diabetes mellitus and its chronic complications. The aim of this study was to evaluate plasma antioxidant status in patients with uncomplicated type 2 diabetes, in order to understand the interactions between its components and the diabetic milieu. METHODS: Plasma samples were collected from 15 patients with type 2 diabetes receiving oral antidiabetic agents and from 18 healthy control subjects without diabetes. Glycosylated haemoglobin was measured as an indicator of blood glucose control. Total and residual antioxidant activities were measured. Lipid peroxides were measured as indicators of plasma oxidative stress. Copper and caeruloplasmin were also assayed as possible pro-oxidants. RESULTS: Antioxidant activities, lipid peroxide level, copper concentration and caeruloplasmin activity were significantly increased in the plasma of patients with diabetes compared with control subjects. CONCLUSIONS: The total antioxidant capacity of plasma was increased, despite high levels of oxidative stress, in patients with uncomplicated type 2 diabetes. Increased levels of copper and caeruloplasmin characterized the diabetic milieu, despite an absence of chronic complications.

Trends in childhood type 1 diabetes incidence in Europe during 1989-2008: evidence of non-uniformity over time in rates of increase.

AIMS/HYPOTHESIS: The aim of the study was to describe 20-year incidence trends for childhood type 1 diabetes in 23 EURODIAB centres and compare rates of increase in the first (1989-1998) and second (1999-2008) halves of the period. METHODS: All registers operate in geographically defined regions and are based on a clinical diagnosis. Completeness of registration is assessed by capture-recapture methodology. Twenty-three centres in 19 countries registered 49,969 new cases of type 1 diabetes in individuals diagnosed before their 15th birthday during the period studied. RESULTS: Ascertainment exceeded 90% in most registers. During the 20-year period, all but one register showed statistically significant changes in incidence, with rates universally increasing. When estimated separately for the first and second halves of the period, the median rates of increase were similar: 3.4% per annum and 3.3% per annum, respectively. However, rates of increase differed significantly between the first half and the second half for nine of the 21 registers with adequate coverage of both periods; five registers showed significantly higher rates of increase in the first half, and four significantly higher rates in the second half. CONCLUSIONS/INTERPRETATION: The incidence rate of childhood type 1 diabetes continues to rise across Europe by an average of approximately 3-4% per annum, but the increase is not necessarily uniform, showing periods of less rapid and more rapid increase in incidence in some registers. This pattern of change suggests that important risk exposures differ over time in different European countries. Further time trend analysis and comparison of the patterns in defined regions is warranted.

Detection of possible restriction sites for type II restriction enzymes in DNA sequences.

In order to make a step forward in the knowledge of the mechanism operating in complex polygenic disorders such as diabetes and obesity, this paper proposes a new algorithm (PRSD -possible restriction site detection) and its implementation in Applied Genetics software. This software can be used for in silico detection of potential (hidden) recognition sites for endonucleases and for nucleotide repeats identification. The recognition sites for endonucleases may result from hidden sequences through deletion or insertion of a specific number of nucleotides. Tests were conducted on DNA sequences downloaded from NCBI servers using specific recognition sites for common type II restriction enzymes introduced in the software database (n = 126). Each possible recognition site indicated by the PRSD algorithm implemented in Applied Genetics was checked and confirmed by NEBcutter V2.0 and Webcutter 2.0 software. In the sequence NG_008724.1 (which includes 63632 nucleotides) we found a high number of potential restriction sites for ECO R1 that may be produced by deletion (n = 43 sites) or insertion (n = 591 sites) of one nucleotide. The second module of Applied Genetics has been designed to find simple repeats sizes with a real future in understanding the role of SNPs (Single Nucleotide Polymorphisms) in the pathogenesis of the complex metabolic disorders. We have tested the presence of simple repetitive sequences in five DNA sequence. The software indicated exact position of each repeats detected in the tested sequences. Future development of Applied Genetics can provide an alternative for powerful tools used to search for restriction sites or repetitive sequences or to improve genotyping methods.

[Association of albuminuria with adipokines, inflammation and insulin resistance in non-diabetic subjects]. / Relatia dintre adipokine, markeri inflamatori, scaderea sensibilitatii la insulina si eliminarea urinara de albumina la subiecti nediabetici.

UNLABELLED: The objective of this study was to evaluate the association of traditional cardiovascular risk factors, adipokines, inflammation and insulin resistance with low-grade urinary albumin-to-creatinine ratio (ACR) in nondiabetic, healthy subjects. MATERIAL AND METHODS: The study included 117 healthy subjects (64 men and 53 women), who were classified according to their body mass index (BMI) into three groups: lean (BMI<25 kg/m2), overweight (25< or =BMI<30 kg/m2) and obese (BMI> or =30 kg/m2). RESULTS: ACR was higher in obese men and women compared to overweight and lean men and women (men - 3 mg/g vs. 6.1 mg/g vs. 8.9 mg/g, p=0.018; women - 2.1 mg/g vs. 6.7 mg/g vs. 9.1 mg/g, p=0.03). In univariate analyses ACR was associated in obese men with adiponectin (r=-0.43, p=0.021) and systolic blood pressure (r=0.51, p=0.006) and in non-obese men with systolic blood pressure (r=0.39, p=0.041). In women systolic blood pressure was the only determinant both in obese (r=0.49, p=0.022) and non-obese subjects (r=0.42, p=0.04). CONCLUSIONS: Adiponectin is an important mediator of low-grade albuminuria in obese, non-diabetic men.

Birthweight and the risk of childhood-onset type 1 diabetes: a meta-analysis of observational studies using individual patient data.

AIMS/HYPOTHESIS: We investigated whether children who are heavier at birth have an increased risk of type 1 diabetes. METHODS: Relevant studies published before February 2009 were identified from literature searches using MEDLINE, Web of Science and EMBASE. Authors of all studies containing relevant data were contacted and asked to provide individual patient data or conduct pre-specified analyses. Risk estimates of type 1 diabetes by category of birthweight were calculated for each study, before and after adjustment for potential confounders.Meta-analysis techniques were then used to derive combined ORs and investigate heterogeneity between studies. RESULTS: Data were available for 29 predominantly European studies (five cohort, 24 case-control studies), including 12,807 cases of type 1 diabetes. Overall, studies consistently demonstrated that children with birthweight from 3.5 to 4 kg had an increased risk of diabetes of 6% (OR 1.06 [95% CI 1.01-1.11]; p=0.02) and children with birthweight over 4 kg had an increased risk of 10% (OR 1.10 [95% CI 1.04-1.19]; p=0.003), compared with children weighing 3.0 to 3.5 kg at birth. This corresponded to a linear increase in diabetes risk of 3% per 500 g increase in birthweight (OR 1.03 [95% CI 1.00-1.06]; p=0.03). Adjustments for potential confounders such as gestational age, maternal age, birth order, Caesarean section, breastfeeding and maternal diabetes had little effect on these findings. CONCLUSIONS/INTERPRETATION: Children who are heavier at birth have a significant and consistent, but relatively small increase in risk of type 1 diabetes.

Caesarean section is associated with an increased risk of childhood-onset type 1 diabetes mellitus: a meta-analysis of observational studies.

AIMS/HYPOTHESIS: The aim of this study was to investigate the evidence of an increased risk of childhood-onset type 1 diabetes in children born by Caesarean section by systematically reviewing the published literature and performing a meta-analysis with adjustment for recognised confounders. METHODS: After MEDLINE, Web of Science and EMBASE searches, crude ORs and 95% CIs for type 1 diabetes in children born by Caesarean section were calculated from the data reported in each study. Authors were contacted to facilitate adjustments for potential confounders, either by supplying raw data or calculating adjusted estimates. Meta-analysis techniques were then used to derive combined ORs and to investigate heterogeneity between studies. RESULTS: Twenty studies were identified. Overall, there was a significant increase in the risk of type 1 diabetes in children born by Caesarean section (OR 1.23, 95% CI 1.15-1.32, p < 0.001). There was little evidence of heterogeneity between studies (p = 0.54). Seventeen authors provided raw data or adjusted estimates to facilitate adjustments for potential confounders. In these studies, there was evidence of an increase in diabetes risk with greater birthweight, shorter gestation and greater maternal age. The increased risk of type 1 diabetes after Caesarean section was little altered after adjustment for gestational age, birth weight, maternal age, birth order, breast-feeding and maternal diabetes (adjusted OR 1.19, 95% CI 1.04-1.36, p = 0.01). CONCLUSIONS/INTERPRETATION: This analysis demonstrates a 20% increase in the risk of childhood-onset type 1 diabetes after Caesarean section delivery that cannot be explained by known confounders.

Combined liver and islet transplantation using steroid-free immunosuppression.

Due to a vicious circle in which HCV favors insulin resistance and, alternatively, insulin resistance facilitates the persistence of HCV, HCV patients have often diabetes associated with liver cirrhosis. We present the case of combined liver and pancreatic islets transplantation performed in a patient with HCV liver cirrhosis associated with insulin-dependent diabetes. This is also the first case of islet allotransplantation in Romania. A 40-year-old male diagnosed with liver cirrhosis due to HCV infection and insulin dependent diabetes underwent combined liver and islet transplantation. Our therapeutic design was based on data provided by both the use of Edmonton immunosuppressive steroid-free protocol in islets cell transplantation and the findings of international studies on the effects of this protocol in liver transplantation for patients with HCV infection. Good metabolic control of the diabetes was obtained. The absence of anti beta cell autoimmunity could explain also the good tolerance for the transplanted islets, proved by the rapid and durable decrease of the insulin need, from 64 U/day to 20 U/day at one month post-transplantation, dose that was maintained for 16 months when the patient died due to recurrent HCV hepatitis. Islet transplantation can be associated to liver transplantation in order to improve the associated diabetes in cirrhotic patients.

For a new paradigm of diabetes.

The main beta cell function is that of pre-proinsulin synthesis and of insulin exocytosis in a regulated manner. After the detachment of a small signal peptide, the remaining proinsulin molecule is transferred in the endoplasmic reticulum. During the emergence of the secretory vesicles and their maturation, proinsulin is split into insulin and C peptide. Diabetes mellitus is characterized by a poor maturation of secretory vesicles explaining the higher levels of proinsulin both in beta cells and in the plasma. The defect is associated to alterations in the exocytosis machinery, initially minor (disappearance of oscillatory pattern of insulin release, and/or the amputation of early phase of insulin response) and later major (a progressive decrease of the overall insulin response). Because the increase in plasma glucose levels is a late indicator of the diabetogenic process (a decrease with more than 50% of beta cell mass/function), we propose as marker of the prehyperglycaemia the high levels of plasma proinsulin or of the proinsulin/insulin ratio. In type 1 diabetes, the autoimmune destruction of beta cell mass will have a fast evolution, while in the type 2 phenotype, the same process takes a slower, but also progressive evolution. In both cases, the decrease in beta cell mass will be induced by an increased apoptosis and the decreased regeneration reaction.

Mortality trends in noninsulin-treated type 2 diabetes mellitus patients in the 1943-2000 period.

AIMS: To investigate the major aspects of mortality in patients with noninsulin-treated type 2 diabetes mellitus (T2DM), from 1942 till 2000. SUBJECTS AND METHODS: We performed a retrospective study in 9698 noninsulin-treated T2DM patients, 5001 (51.6%) males and 4695 (48.4%) females, registered in Bucharest Diabetes Center and deceased between 1943 and 2000. For each patient the age at diabetes onset, disease duration, age at death, cause of death, sex, height and weight were recorded. RESULTS: The mean age at diabetes onset was 58.3 +/- 9.1 years in 1943-1960 period (no significant differences by sex) and 60.6 +/- 10.3 years in 1981-2000 (59.3 +/- 10.3 years in males and 61.8 +/- 10.1 years in females, p < 0.01 vs. males). The mean disease duration at death was 7.7 +/- 5.2 years in 1943-1960 period (no significant differences by sex) and 11.3 +/- 8.1 years in 1981-2000 (11.9 +/- 8.4 years in males and 10.7 +/- 7.6 years in females, p < 0.01 vs. males). The mean age at death was 66 +/- 9.8 years in 1943-1960 period (no significant differences by sex) and 71.9 +/- 9.7 years in 1981-2000 (71.2 +/- 9.9 years in males and 72.5 +/- 9.5 years in females, p < 0.01 vs. males). In the Cox regression analysis, an increase in mortality was associated with the masculine sex--9.6% (CI 95% 1-19%, p = 0.028) compared with feminine sex; 1 year increase in age at onset--4.8% (CI 95% 4.3-5.3%, p < 0.01); 1 kg/m2 increase in body mass index--2.9% (CI 95% 1.9-3.8%, p < 0.01); 1 mg/dl increase in mean fasting blood glucose--0.1% (CI 95% 0-0.2%, p = 0.025). The major causes of death in noninsulin-treated T2DM patients in the 1981-2000 period were: ischemic heart disease (53.8%), stroke (14.4%), cancer (9%), digestive diseases (6.3%), diabetes (5.3%), end stage renal disease (4.6%), infections (2.7%), diabetes coma (2.2%) and others (1.7%). CONCLUSIONS: There is a statistically significant increase in the proportion of death caused by ischemic heart disease, while infections significantly decreased in importance during the study period. The masculine sex, age at onset, mean fasting blood glucose and body mass index were all significant predictors of mortality in the Cox regression analysis, adjusted for the year of death.

Glucose evaluation trial for remission (GETREM) in type 1 diabetes: a European multicentre study.

OBJECTIVE: Strict metabolic control during the 1st year of type 1 diabetes is thought to be a key factor for achieving clinical remission. The aims of this study were two-fold: (i) to evaluate the frequency and duration of spontaneous remission (defined according to the parameters issued by the International Diabetic Immunotherapy Group (IDIG)) in a European population of consecutive recent onset type 1 diabetes patients (aged 5-35 years), followed-up for a period of 36 months with a common protocol of intensive insulin therapy and without adjunct immune-intervention; and (ii) to identify the predictive factors for clinical remission. RESEARCH DESIGN AND METHOD: A total of 189 consecutive patients with newly diagnosed type 1 diabetes according to ADA criteria were recruited in participating centres (Belgium, Czech Republic, Estonia, France, Germany, Hungary, Italy, Poland, Romania, Sweden and Turkey) and followed-up for a period of up to 36 months. In all patients, intensive insulin therapy was implemented consisting of three or four injections of regular insulin daily with NPH insulin at bedtime. Adjustment of insulin dose was made according to a common protocol. Various clinical characteristics (age, gender, severity of presentation, etc.), history (presence of diabetic siblings in the family, etc.) and integrated parameters of metabolic control (HbA(1c), blood glucose, the total insulin dose at hospital discharge adjusted for body weight) were collected. RESULTS: Twenty-two patients (11.6%) experienced remission. The median duration of remission was 9.6 months and the range was 31 months. There was a wide variation among centres. Logistic regression analysis focused on the centre as the main variable in achieving remission. CONCLUSION: Remission was shown to be very heterogeneous between centres depending on 'other factors' such as patient care and family awareness of the disease rather than on 'measurable factors' such as sex, age, HbA(1c) and severity of presentation at diagnosis. Using intensive insulin therapy and optimisation of metabolic control, remission occurred in nearly one out of eight patients.

Meal testing and postprandial state of type 2 diabetic patients with metabolic syndrome.

BACKGROUND AND AIMS: C reactive protein (CRP), a non-specific acute phase reactant, has been associated with multiple patogenic mechanisms involved in chronic illnesses, but up to now the significance of CRP in the postprandial state in diabetes mellitus has not been addressed. MATERIAL AND METHODS: We evaluated 58 type 2 diabetic patients (33F/25 M) with associated metabolic syndrome. The main characteristics of the patients were: age 58.1+/-9.15 years, duration of diabetes 3.9+/-3.07 years, BMI 26.2+/-3.26 kg/m2, waist circumference 97.7+/-9.88 cm and HbA1c 7.2+/-1.2%. Men and women were matched for age, duration of diabetes, BMI and HbA1c. The patients had a 330 kcal standard meal, blood samples were taken in fasting condition and 2 and 4 hours postprandial and the following parameters were obtained: glycemia, total cholesterol, HDL-cholesterol, triglycerides, apolipoprotein A1 and B and also CRP levels. The patients were also evaluated through duplex scan 2D ultrasound for intima-media thickness (IMT) of common carotid artery bilaterally. Data were analysed with Epi Info, SPSS and Statistica Software. RESULTS: Fasting CRP correlated to BMI and waist circumference (p=0.0068 and p=0.038 respectively). At two hours postprandial, we found a significant nonparametric correlation between CRP level and total cholesterol (p=0.01), which remained significant even after adjusting for age, BMI, HbA1c and blood pressure values (adjusted p=0.018). Patients in the lowest quartile for CRP level compared to those in the highest quartile had lower fasting apolipoprotein B levels (146 vs 197 mg/dl, p=0.042), lower postprandial blood glucose levels (188 vs 241 mg/dl, p=0.035) and lower nonHDL-cholesterol levels (148 vs 192 mg/dl, p=0.005). Common carotid artery IMT correlated with the duration of diabetes (p=0.026) and systolic blood pressure values both in clino and orthostatism (p=0.007 and p=0.006 respectively). CONCLUSION: The results confirm that C reactive protein and apolipoprotein B have close relationships with other components of the metabolic syndrome in type 2 diabetic patients. High CRP and apolipoprotein B levels could be a marker for an excessive postprandial response, leading to an increased risk for chronic vascular complications and atherogenesis.

Intradermal reactions to purified protein derivative in patients with diabetes mellitus.

Diabetes mellitus is known to adversely affect the immune system. Immune dysfunction is also associated with the etiology of diabetes mellitus. Immune dysfunction is associated with diminished chemotactic, phagocytic and monocyte activity. There is also increased T-cell activity. All these are associated with acute hyperglycemia. We investigated the cellular arm of the immune system of patients with diabetes mellitus using intradermal reactions (IDR) to purified protein derivative (PPD). Both groups high blood glucose [HBG] vs. low blood glucose [LBG]) were homogeneous in terms of size and sex and average age (24. vs. 22.; 21 F vs 25 M; 56.5yrs. vs. 54.5 yrs.). The LBG had a greater average duration of diabetes (13.6 yrs vs. 9.3 yrs), which suggests an increased tendency to complications of diabetes mellitus. The results showed an average blood glucose and IDR (HBG vs. LBG) of 235.8 +/- 46.5 mg/dl vs. 144.3 +/- 26.7 mg/dl and 18.5 +/- 8.5 mm vs. 12.2 +/- 7.0 mm respectively. These results showed that IDR is significantly affected by hyperglycemia. This increased IDR may be a consequence of the synergy between interferon-gamma and tumor necrosis factor alpha which is a significant factor in diabetes. Also, there is an accentuation of this synergy following injection of PPD. It appears to be clear that IDR to PPD may be influenced by the diabetic state, especially acute hyperglycemia. However, it also appears that IDR to PPD may not be an adequate method for assessing cutaneous cell-mediated immunity.

Strong association of insulin gene INS-VNTR polymorphisms with type 1 diabetes in the Romanian population.

Type 1 diabetes (T1DM) is a common, chronic disease with autoimmune pathogeny, conditioned by genetic factors. Class II HLA DR and DQ and insulin gene polymorphisms encode for most of the T1DM genetic susceptibility. We have previously shown that class I alleles of the insulin gene INS-VNTR locus are strongly associated with T1DM in the Romanian population. The aim of our study was to confirm the contribution of INS-VNTR to T1DM genetic susceptibility in Romania. For this we typed the insulin gene -23HphI A/T polymorphism (an accurate marker for the INS-VNTR alleles) on 219 Romanian T1DM families using Taqman. Allele transmission to diabetics and unaffected siblings was assessed using the Transmission Disequilibrium Test (TDT). We found a significantly increased transmission of -23HphI A allele to diabetics (78.31% transmission, pTDT = 2.4 e-07) which confirms our previous findings. Combined with the data from the first 204 Romanian T1DM families, the transmission of -23HphI A allele to diabetics is almost 80% (79.78%, pTDT = 2.8 e-15). This percentage indicates the same level of predisposition as for the most diabetogenic HLA's. In conclusion, our results indicate an exceptionally strong association of the class I INS-VNTR alleles with T1DM for the Romanian population.