Role of the C1858T polymorphism of protein tyrosine phosphatase non-receptor type 22 (PTPN22) in children and adolescents with type 1 diabetes.

In recent years, increasing interest has been devoted to the susceptibility gene polymorphisms in type 1 diabetes (T1D) as well as in other autoimmune diseases. Among these, a nucleotide polymorphism of the gene encoding for the protein tyrosine phosphatase non-receptor type 22 (PTPN22) has been associated with T1D in several studies. The aim of this study is to define the frequency of the C1858T polymorphism in the PTPN22 gene in a cohort of 113 Caucasian patients (58 males and 55 females) with T1D, and to assess a possible correlation with a group of clinically relevant variables: age at onset, gender, diabetes-related autoantibodies, residual ß-cell function and daily insulin requirement (IR) 6 months after diagnosis. Using a PCR-RFLP approach, we evidenced a 17.7% frequency of the PTPN22 C1858T polymorphism in diabetic patients, higher than the frequency showed in the general population. A statistically significant correlation between this polymorphism and higher levels of C-peptide at diagnosis and lower IR at 6 months from diagnosis was observed (P=0.001 and P=0.04). Moreover, 1858T variant carriers were more frequently positive for glutamic acid decarboxylase (GAD) autoantibodies at diagnosis than wild-type subjects (P=0.19). On the other hand, no significant difference regarding age at onset, gender distribution, insulinoma-associated 2 molecule (IA2) and islet cell antibodies (ICA) positivity was found. These findings, if adequately confirmed in the future and extended to larger samples, may characterize a subset of T1D patients with a defined genetic pattern, who may be eligible for trials aimed to preserve residual ß-cell function in the coming years.

Therapeutic implications of novel mutations of the RFX6 gene associated with early-onset diabetes.

Identification of the genetic defect underlying early-onset diabetes is important for determining the specific diabetes subtype, which would then permit appropriate treatment and accurate assessment of recurrence risk in offspring. Given the extensive genetic and clinical heterogeneity of the disease, high-throughput sequencing might provide additional diagnostic potential when Sanger sequencing is ineffective. Our aim was to develop a targeted next-generation assay able to detect mutations in several genes involved in glucose metabolism. All 13 known MODY genes, genes identified from a genome-wide linkage study or genome-wide association studies as increasing the risk of type 2 diabetes and genes causing diabetes in animal models, were included in the custom panel. We selected a total of 102 genes by performing a targeting re-sequencing in 30 patients negative for mutations in the GCK, HNF1α, HNF4α, HNF1ß and IPF1 genes at the Sanger sequencing analysis. Previously unidentified variants in the RFX6 gene were found in three patients and in two of them we also detected rare variants in WFS1 and ABCC8 genes. All patients showed a good therapeutic response to dipeptidyl peptidase-4 (DPP4) inhibitors. Our study reveals that next-generation sequencing provides a highly sensitive method for identification of variants in new causative genes of diabetes. This approach may help in understanding the molecular etiology of diabetes and in providing more personalized treatment for each genetic subtype.

Skipping Breakfast Is Associated with an Atherogenic Lipid Profile in Overweight and Obese Prepubertal Children.

BACKGROUND: Skipping breakfast has been associated with a higher risk of obesity and cardiovascular (CV) risk factors. However, it is not known if skipping breakfast is also correlated with CV risk factors independently from obesity. The mechanisms explaining the role of skipping breakfast on promoting fat accumulation as well as CV risk are not known. Hormones, in particular, insulin-like growth factor-1 (IGF-1), may potentially play a role in the metabolic profile of breakfast skippers. AIM: This cross-sectional study aims to test, in a sample of overweight/obese children, the hypotheses that skipping breakfast is associated with a worse metabolic profile and that IGF-1 levels are associated with this unfavorable metabolic profile. METHODS AND RESULTS: We enrolled 112 overweight/obese prepubertal children (3-12 years). Anthropometric characteristics (height SDS, weight SDS, and body mass index (BMI) z-score) were measured. Blood samples were collected to evaluate glucose and lipid metabolisms and hormone profile (growth hormone (GH), IGF-1, insulin, and cortisol). The triglycerides/high-density lipoprotein (HDL) cholesterol ratio was calculated as a predictor of cardiovascular risk. Children were divided into two groups according to breakfast habits: consumers (≥5 weekly; N = 76) and skippers (≤4 weekly; N = 36). Glycaemia, total and low-density lipoprotein (LDL) cholesterol, triglycerides (p < 0.05), and triglycerides/HDL cholesterol ratio (p < 0.001) were higher, while HDL cholesterol was lower (p < 0.01) in skippers as compared to consumers. IGF-1 concentrations were inversely correlated with LDL cholesterol (r = -0.279, p=0.013) and directly correlated with HDL cholesterol (r = 0.226, p=0.047). IGF-1 correlated positively with HDL cholesterol (r = 0.266, p=0.045) in consumers and correlated negatively with LDL cholesterol (r = -0.442, p=0.024) in skippers. Breakfast consumption among prepubertal overweight/obese children showed a better lipid profile in comparison with those who skipped breakfast [OR: 0.165 (95% CI: 0.053-0.518), p=0.001]; these latter odds of the increased triglycerides/HDL cholesterol ratio was 6.1-fold higher. CONCLUSIONS: Breakfast skippers show a worse lipid profile when compared to breakfast consumers. IGF-1 might play a role as an independent modulator of lipid metabolism.

Can insulinoma cause generalised epilepsy?

Insulinoma is a common cause of seizures due to recurrent hypoglycemic crises. Surgical treatment usually results in disappearance of such seizures. We describe a previously healthy 17 year-old girl who became epileptic after the onset of insulinoma with persistent seizures after surgical removal of the tumour. Insulinoma must be taken into account for differential diagnosis with convulsions of unknown origin, and even after metabolic normalization it may cause epilepsy.

Recent advances on autosomal dominant nocturnal frontal lobe epilepsy: "understanding the nicotinic acetylcholine receptor (nAChR)".

Autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) is characterized by clusters of nocturnal motor seizures, which are often stereotyped and brief. They vary from simple arousals during sleep to dramatic, bizarre, hyperkinetic events with tonic or dystonic features. A minority of patients may experience aura. This disease is caused by various mutations of genes coding for subunits of neuronal acetylcholine receptor comprising the sodium/potassium ion channel. Recent advances in molecular genetics have provided the means for a better understanding of human epileptogenesis at a molecular level, which can facilitate clinical diagnosis and provides a more rational basis of therapy of this form of epilepsy. In this review, we report the recent data in the genetics of ADNFLE.

HLA DR/DQ alleles and risk of type I diabetes in childhood: a population-based case-control study.

The objective was to evaluate HLA DR/DQ alleles and their risk factor for type 1 diabetes in the Abruzzo region (central Italy). Sixty incident cases from the Abruzzo region were studied together with 120 unrelated control subjects living in the same administrative areas. The relative risk of diabetes associated with the alleles under study was calculated by deriving the odds ratio (OR) maximum likelihood estimates and their 95% confidence intervals (CI) by the exponentiation of the logistic regression beta-parameter. The combination DRB1*03/DQA1*0501/DQB1*0201 was found in 20.0% of patients and 7.1% of the control subjects, conferring an OR of 4.04 and a CI of 1.97-8.49. The combination DRB1*04/DQA1*0301/DQB1*0302 was found in 23.3% of diabetic patients and 6.7% of controls, giving an OR of 5.69 and a CI of 2.77-12.05. DRB1*11/DQA1*0505/DQB1*0301 and DQA1*0505/DQB1*0301 were negatively associated with type 1 diabetes (OR=0.27, CI 0.11-0.57; OR=0.07, CI 0.02-0.19). The DQA1 genotype at risk was found to be DQA1*0301/DQA1*0501: OR=23.80, CI 2.97-190.89, as it occurred with the highest frequency in the patient group. The DQB1 genotype at risk was found to be DQB1*0201/DQB1*0302, which occurred in 13.3% of patients but in only 1.1% of the control group (OR=29.75, CI 5.36-549.25). Our results shed further light on the risk of development of this disease during a specific time period in an area where the overall incidence of type 1 diabetes is known.

Inhibitory effects of peripheral blood cells on in vitro colony formation by autologous bone marrow in aplastic anaemia: relation with response to immunosuppressive therapy.

The inhibitory activity of peripheral blood lymphocytes on autologous bone marrow was studied in 27 patients with aplastic anaemia after treatment with androgen. Inhibitory activity was hard to assess in 10 patients studied during the first year of treatment. The colony count was too low to be certain of differences between the samples incubated with or without lymphocytes. Among the 17 patients who had more than 10 colonies per 2 x 10(5) mononuclear bone marrow cells, nine showed inhibitory activity by peripheral blood lymphocytes. After 12 months of androgen therapy each of these patients showing inhibitory activity of bone marrow colony forming cells by peripheral lymphocytes responded to antithymocyte globulin. None of nine patients with few colony forming cells or no inhibitory activity of lymphocytes responded to immunosuppression.

Severe hypoglycemia in insulin-dependent diabetic children treated by multiple injection insulin regimen.

The occurrence and risk factors of severe hypoglycemic attacks were analyzed during a 4-year study in a group of children and adolescents who received human insulin and followed a multiple daily injection regimen (three or four injections per day); 29 patients experienced severe hypoglycemia at least once in 4 years. Of these, 13 suffered recurrent episodes: 8 had two episodes, 4 had four episodes, and 1 patient had seven episodes. For comparative purposes, the nonhypoglycemic population (217 diabetic children) was used as a control group. The hypoglycemic children received insulin doses which were significantly higher than for nonhypoglycemic patients (1.05 +/- 0.6 U/kg daily vs 0.87 +/- 0.7; P < 0.05). Moreover, the hypoglycemic group had a significantly higher mean number of previous episodes of severe hypoglycemia than the nonhypoglycemic group (0.98 +/- 1.2 vs 0.26 +/- 0.7; P < 0.001). There was no significant difference in age, sex, duration of disease, and metabolic control between hypoglycemic and nonhypoglycemic children. There was no association between severe hypoglycemia and the presence of retinopathy, persistent microalbuminuria, or autonomic neuropathy. Severe hypoglycemia is a recurrent problem, not related to the quality of metabolic control nor to the presence of long-term microvascular complications, and diabetic children with a personal history of severe hypoglycemia are at risk for future episodes.

Family history and risk of insulin-dependent diabetes mellitus: a population-based case-control study.

Insulin-dependent diabetes mellitus (type 1) is a common chronic disease of childhood occurring throughout the world. In the literature, its most important determinants include genetic, environmental and familial factors. We evaluated family history as a determinant of the risk of type 1 diabetes mellitus with a population-based case-control study. Information about type 1 patients was taken from the dedicated register of the Abruzzo Region; the register has been collecting incident cases in the age group 0-14 years, diagnosed between 1 January 1990 and 31 December 1996. The control group was taken from the lists of patients attending family pediatricians. The family history data for type 1 and type 2 patients was obtained by a questionnaire, administered to their parents. The risk of type 1 diabetes mellitus associated with its occurrence in first- and second-degree relatives was estimated using logistic regression methods. Our results show that the risk is indeed increased with a positive family history (OR=3.96; 95% CI 1.54-10.14). This shows that the risk of type 1 diabetes mellitus for children whose fathers are affected by the disease is 11 times higher with respect to controls. Moreover, the risk for children whose brothers are affected by the disease is 20 times higher with respect to controls. In contrast, a family history for type 2 diabetes mellitus does not influence the risk.

[Myelodysplastic syndrome: experience of the Study and Treatment of Bone Marrow Failure Group]. / Sindromes mielodisplásticos: experiencia del Grupo de Estudio y Tratamiento de las Insuficiencias Medulares (GETIM).

Myelodysplastic syndromes (SMD) were studied in 58 patients (37 men, 21 women; mean age 61 years, range 18-81) who were grouped according to FAB criteria (Table 1). None of them showed a secondary SMD to medullary toxic agents or cytostatic treatments although 5 presented concomitant neoplastic disease. Morphologic alterations in peripheral blood smears and bone marrow were registered by 3 hematologists working independently. The intracellular and extracellular iron deposits were evaluated in every case with Perls; peroxidase activity was determined in 16 patients and intraleucocitary alkaline phosphatase reaction was carried out in 17 patients. Twenty five patients (43%) had refractory anemia (RA); 10 (17%) sideroblastic anemia; 13 (25%) refractory anemia with excess of blasts (AREB); 3 (5%) AREB in transformation (AREB-T) and 7 myelomonocytic leukemia (LMMC). Clinical manifestations at diagnosis are described in Table 2. In the observation period there were cases of anemia requiring transfusion, bacterial infections, muco-cutaneous hemorrhage and hemorrhagic episodes in the central nervous system. In the bone marrow smears the cellularity was normal or increased in 53 cases and diminished in only 3. The degree of dysplastic characteristics (erythroid, granulocytic and megakaryocytic) ranged from low to severe. It was low in most of AR, being the erythroid population the most affected in AS and the granulocytic one in AREB and AREB-T. Patients with LMMC showed similar characteristics to those with myeloproliferative syndromes and the differential diagnosis were sometimes difficult, accounting for their separate inclusion in Table 4. Out of 23 patients, 5 presented clonal pathology detected in cytogenetic studies.(ABSTRACT TRUNCATED AT 250 WORDS)

[The families of diabetic children: a 2-year follow-up]. / Studio su famiglie di bambini diabetici: follow-up di 2 anni.

A great amount of clinical and experimental evidence has been accumulated on the role of immunological early events in the development of type 1 diabetes mellitus. In order to try to make a precocious diagnosis of type 1 diabetes mellitus, the Authors have studied all the components of the family in a group of diabetic children. This study is a part of a collaborative International Study called IFS (International Family Study). The Authors describe the scheme of this project in detail. During this study the Authors made a very early diagnosis of diabetes in a child, brother of another diabetic boy. The importance of this approach to the diabetic disease is discussed.

Acute interhemispheric subdural haematoma. A case report.

Acute interhemispheric subdural haematoma (AISH) was considered extremely rare until identification with imaging studies. Interhemispheric subdural hematoma in adults is a rare complication of head injury with no more than 100 cases reported since 1940. The classical presentation of this disorder is a contralateral monoparesis of the leg or a hemiparesis more pronounced in the leg1. Treatment may consist of conservative observation or craniotomy and is dictated by the clinical course. Conservative management is the treatment of choice for patients without disturbances of consciousness and for patients with stable clinical conditions. Surgical treatment is necessary in patients with progressive neurological deterioration. We describe the case of traumatic AISH in a 31-year-old patient who presented a contralateral monoparesis of the leg.

Positional cloning of a cyromazine resistance gene in Drosophila melanogaster.

Cyromazine is an effective insecticide used to control dipteran insects. Its precise mode of action is yet to be determined, although it has been suggested that it interferes with the hormone system, sclerotization of the cuticle, or nucleic acid metabolism. To understand the way in which cyromazine acts, we have positionally cloned a cyromazine resistance gene from Drosophila melanogaster. Six cyromazine resistance alleles had previously been generated by ethyl methanasulphonate treatment. Two of these failed to complement each other and here we identify them as having independent non-sense mutations in CG32743, which is an ortholog of Smg1 of worms and mammals and encodes a phosphatidylinositol kinase-like kinase (PIKK). RNAi experiments confirm that cyromazine resistance can be achieved by knocking down CG32743. These are the first cyromazine resistant mutations identified at the nucleotide level. In mammals Smg1 phosphorylates P53 in response to DNA damage. This finding supports the hypothesis that cyromazine interferes with nucleic acid metabolism.

[Immunologic changes in diabetic ketoacidosis]. / Alterazioni immunologiche in corso di chetoacidosi diabetica.

We studied 13 children and adolescents during diabetic ketoacidosis; the duration of diabetes ranged from 1.4 to 6.0 years. A group of 13 diabetic sex, age and duration of disease-matched children served as control. Patients in ketoacidosis showed important abnormalities of T subset percentages (OKT3: 63.4 +/- 1.87% vs 72.1 +/- 3.4; p less than 0.001. OKT4: 37.18 +/- 1.85% vs 44.6 +/- 3.9; p less than 0.01. OKT8: 28.5 +/- 6.51% vs 28.1 +/- 1.9; p less than 0.04) and impaired neutrophil chemotaxis (53.10 +/- 3.3 vs 88.1 +/- 7.2; p less than 0.001). The patients showed normal levels of all classes of immunoglobulins. No correlation was observed between these abnormalities and the degree of ketoacidosis or glycaemia. When the patients were re-evaluated out of ketoacidosis, the values of the immunological parameters were normal and similar to those of the control group.

Autonomic neuropathy in diabetic children.

OBJECTIVE: Evaluate the presence of cardiovascular autonomic nerve dysfunction in children and adolescents with insulin-dependent diabetes mellitus. METHODOLOGY: We studied 110 patients (54 male, 56 female) and 100 healthy sex and age-matched children. Autonomic nerve function was assessed by standard cardiovascular reflex tests: (1) Fall in systolic blood pressure in response to standing. (2) Heart rate in response to standing. (3) Beat-to-beat rate variation during deep breathing. (4) Quotient of heart rate during and after Valsalva manoeuvre. (5) Change in blood pressure response to sustained handgrip. The coefficient of variation of heart rate was determined from 150 systoles using a microcomputer-based technique. The lower limits of normal were defined according to statistical analysis taking into account the relationship between heart rate variability and age. RESULTS: Forty-seven of the 110 diabetic children and adolescents studied showed one or more abnormal tests for cardiovascular autonomic dysfunction; many patients had an abnormality in more than one test. Twenty-two patients showed early involvement, 18 patients had definite and 7 severe involvement. No correlation was found between sex, glycaemic control, duration of diabetes or presence of retinopathy and persistent microalbuminuria and the autonomic nerve function. CONCLUSIONS: In the paediatric age group also, autonomic nerve dysfunction can be present in asymptomatic diabetic patients. Heart rate variation during Valsalva manoeuvre and maximum/minimum 30:15 ratio are the most sensitive indices to detect autonomic abnormalities in children.

Education, knowledge and metabolic control in children with type 1 diabetes.

We studied thirty diabetic patients and we evaluated their knowledge of main topics of diabetes mellitus. The level of the knowledge was evaluated by multiple choice questionnaires. On the basis of score obtained the patients were divided into two groups: Group A, with high knowledge level, Group B, with low knowledge level. All the patients were followed-up for a 12 months period after a careful education. At the end of follow-up, we compared the Group A patients with another group of 14 diabetic children, who have followed an educational programme from the diagnosis of the disease (Group C). We assessed the knowledge score and the principal metabolic parameters in the three groups of patients; during the follow-up, we found a significant increase of these parameters in Group A and B patients, more evident in Group A patients. At the end of follow-up, the Group C patients showed a higher knowledge score and metabolic parameters than the Group A children. This study shows that education of disease is important for the increase of metabolic parameters and its usefulness is higher if is carried out from the onset of the disease.