Nonobese Diabetic (NOD) Mouse Dendritic Cells Stimulate Insulin Secretion by Prediabetic Islets

In the Nonobese diabetic (NOD) mouse, a spontaneous model of type 1 diabetes, the pathogenic process is classically thought to start at 3-4 weeks of age with an accumulation of antigen-presenting cells (APC), especially CD11c⁺ dendritic cells (DC), around the pancreatic islets of Langerhans. Concomitantly, hyperinsulinemia and slight hyperglucagonemia are observed, which may be either the cause or consequence of the initial APC infiltration. To determine whether infiltrating DC can affect islet activity in control (C57BL/6) and NOD mice, we performed experiments in which islets and DC were isolated and co-cultured. We first showed that, immediately after isolation, islets from 8-week-old prediabetic NOD mice had significantly higher insulin and glucagon contents than those from C57BL/6 controls. Moreover, as is the case in vivo, prediabetic NOD mouse islets secrete more insulin in vitro at 11.1 mM glucose than C57BL/6 ones. In DC-islet co-cultures, insulin secretion was significantly increased for NOD mice only, while that of glucagon was not significantly affected. These findings indicate that NOD DC are good candidates for stimulating the NOD mouse &#103 -cell hyperactivity that is observed both in vivo and in vitro, and might, consequently, sensitize NOD islets to an autoimmune attack.     

Could FISH on buccal smears become a new method of screening in children suspect of HNF1B anomaly?

HNF1B gene anomalies include renal development defects associated with cysts and are well known by pediatric nephrologists that ask for molecular analysis of this gene. Two types of genomic rearrangements are reported: mutation and more frequently deletion. Using microsatellites or CGH array the size of the deletion was found to be at least of 1.2 Mb including 15 genes among which HNF1B, leading to the diagnosis of chromosomal microdeletion. Fluorescent In Situ Hybridization (FISH) is a simple routinely performed technique, considered as the referring tool to diagnose microdeletion in genetic practice. We performed interphasic FISH on buccal smears from 6 patients known to have HNF1B deletion to valid our technique and to determine the size of the 17q12 deletion. All the patients were found to present a 17q12 microdeletion. Our results showed that FISH is a rapid, reliable and specific technique to diagnose 17q12 microdeletion and might be performed as non invasive sampling procedure useful in pediatric practice. In conclusion we propose to use interphasic FISH to screen pediatric patients presenting with renal abnormalities possibly linked to HNF1B anomaly. Molecular analysis and MLPA (Multiplex Ligand Probe Analysis) could be performed in cases with normal interphasic FISH to detect a point mutation of the gene or more rarely a single exon deletion.     

Improving outcomes of acute myocarditis in children

Acute viral myocarditis may impair prognosis in children of all ages. Its true incidence is underestimated because of heterogeneity of presentation and outcome. Patients may either recover or progress to chronic cardiomyopathy or death. Improving short-term and long-term prognosis is challenging but can probably be achieved by new diagnostic techniques and novel targeted therapies. The objectives of this review are: (1) to detail the current state of knowledge of the pathophysiological mechanisms of acute myocarditis; (2) to provide an update on diagnostic tools such as magnetic resonance imaging and endomyocardial biopsy; and (3) to present new insights in therapeutic strategies, targeted therapies and management of fulminant cases. Options for improving outcomes in acute myocarditis in the pediatric population are discussed.     

Early visual ERPs are influenced by individual emotional skills

Processing information from faces is crucial to understanding others and to adapting to social life. Many studies have investigated responses to facial emotions to provide a better understanding of the processes and the neural networks involved. Moreover, several studies have revealed abnormalities of emotional face processing and their neural correlates in affective disorders. The aim of this study was to investigate whether early visual event-related potentials (ERPs) are affected by the emotional skills of healthy adults. Unfamiliar faces expressing the six basic emotions were presented to 28 young adults while recording visual ERPs. No specific task was required during the recording. Participants also completed the Social Skills Inventory (SSI) which measures social and emotional skills. The results confirmed that early visual ERPs (P1, N170) are affected by the emotions expressed by a face and also demonstrated that N170 and P2 are correlated to the emotional skills of healthy subjects. While N170 is sensitive to the subject’s emotional sensitivity and expressivity, P2 is modulated by the ability of the subjects to control their emotions. We therefore suggest that N170 and P2 could be used as individual markers to assess strengths and weaknesses in emotional areas and could provide information for further investigations of affective disorders.     

Sociodemographic factors associated with the dental health of persons with diabetes in France

This paper describes and compares the oral health status among people with and without diabetes in France, and analyzes the related socioeconomic factors. The study is based on data from the cross‐sectional national health survey conducted in France from 2002 to 2003, which included 19,231 people over 35 years of age, among whom 1,111 reported having diabetes. Data were collected through interviews that inquired about oral health status and use of dental care services, income, educational level, health insurance, place of residence, and birthplace. The prevalence of oral health problems was higher among subjects who had diabetes, compared with those who were nondiabetic (16.4% vs. 13.4%). Dental care utilization during the survey period was reported to be 8.7% among subjects who were diabetic versus 12.9% among those who were nondiabetic. The subjects with diabetes were more likely to have dental problems (OR = 1.47, CI = 1.03–2.08) and wear removable dentures (partial and complete) when their income was lower (OR = 2.17, CI = 1.52–3.10). There were social inequalities in oral health among people with diabetes in France according to income level.     

Prevalence of Thoracic Aortic Aneurysms in Patients with Degenerative Abdominal Aortic Aneurysms: Results from the Prospective ACTA Study

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Matricryptins and matrikines: biologically active fragments of the extracellular matrix

Numerous extracellular proteins and glycosaminoglycans (GAGs) undergo limited enzymatic cleavage resulting in the release of fragments exerting biological activities, which are usually different from those of the full‐length molecules. In this review, we define matrikines and matricryptins, which are bioactive fragments released from the extracellular matrix proteins, proteoglycans and GAGs and report their major biological activities. These fragments regulate a number of physiopathological processes including angiogenesis, cancer, fibrosis, inflammation, neurodegenerative diseases and wound healing. The challenges to translate these fragments from molecules biologically active in vitro and in experimental models to potential drugs are discussed in the last part of the review.