Multiple capillary malformations of progressive onset: Capillary malformation-arteriovenous malformation syndrome (CM-AVM).

BACKGROUND: Capillary malformation-arteriovenous malformation syndrome (CM-AVM) is an autosomal dominant disorder first described in 2003. PATIENTS AND METHODS: An 8-year-old girl was referred for the progressive appearance of multiple capillary malformations in childhood, evocative of CM-AVM syndrome. Molecular analysis of the RASA1 gene revealed a mutation but further examinations did not show arteriovenous malformation. DISCUSSION: CM-AVM syndrome is an autosomal dominant disease caused by RASA1 gene mutations. More than 100 mutations have been identified to date. The EPHB4 gene may also be involved. Capillary malformations with particular characteristics are described. High-flow vascular malformations are associated in 18.5% of cases, with 7.1% being intracerebral. CONCLUSION: CM-AVM syndrome is a recent diagnostic entity. Diagnosis should be considered in the presence of multifocal capillary malformations. This diagnosis may lead to the detection of high-flow arteriovenous malformation and raises the question of specific management for these patients.

Highly scalable femtosecond coherent beam combining demonstrated with 19 fibers.

Coherent beam combining in the femtosecond regime of a record number of 19 fibers is demonstrated. The interferometric phase measurement technique, particularly well suited to phase-lock a very large number of fibers, is successfully demonstrated in the femtosecond regime. A servo loop is implemented to control piezoelectric fiber stretchers for both phase and delay variation compensation. The residual phase errors are below λ/60 rms. Nearly 50% of the total energy is contained in the far-field central lobe. After compression, we obtain a combined pulse width of 300 fs identical to the master oscillator pulse width.

Experimental dog model for assessment of fasting and postprandial fatty acid metabolism: pitfalls and feasibility.

The dog is a widely-used model for conducting metabolic studies. This is mainly due to its large size and its physiology which is relatively similar to that of humans. Here, we attempted to optimize a postprandial metabolic study protocol used in dogs. Following acclimatization, female mongrel dogs underwent 9 h profiling for time-course baseline plasma data on triglyceride, adrenocorticotropic hormone (ACTH) and cortisol levels. One week later, carotid and jugular catheters were surgically inserted for sampling and infusions. Initial post-operative care, based on the literature (Protocol 1), consisted of analgesia (buprenorphine every 8-12 h and 2-3 doses/day of acepromazine), restriction by Pavlov harness within cages, and a two- to three-day recovery period. Throughout the experiment, dogs received a lipid tracer diluted in 5% bovine serum albumin (BSA). Compared with baseline, animals vomited (n = 6/6) and exhibited high ACTH + cortisol levels (stress biomarkers), resulting in blunted triglyceride peak levels. To avoid these undesirable effects, post-operative care was modified (Protocol 2) as follows: animals (n = 19) were given a single dose of buprenorphine and no acepromazine, were unrestrained and free to move within cages, the recovery period was extended to seven days, and the lipid tracer was diluted in 0.002% versus 5% BSA. Using this modified protocol, postprandial plasma-triglyceride and ACTH/cortisol patterns were similar to baseline values. Controlling for stressors, as well as for factors which may alter proper digestion, is critical for all postprandial metabolic studies. Our results show that an optimized postprandial metabolic protocol used in dogs reduces experimental variability, while improving animal care and comfort.

Lasting alterations of the sodium current by short-term hyperlipidemia as a mechanism for initiation of cardiac remodeling.

Clinical and animal studies indicate that increased fatty acid delivery to lean tissues induces cardiac electrical remodeling and alterations of cellular calcium homeostasis. Since this may represent a mechanism initiating cardiac dysfunction during establishment of insulin resistance and diabetes or anaerobic cardiac metabolism (ischemia), we sought to determine if short-term exposure to high plasma concentration of fatty acid in vivo was sufficient to alter the cardiac sodium current (INa) in dog ventricular myocytes. Our results show that delivery of triglycerides and nonesterified fatty acids by infusion of Intralipid + heparin (IH) for 8 h increased the amplitude of INa by 43% and shifted its activation threshold by -5 mV, closer to the resting membrane potential. Steady-state inactivation (availability) of the channels was reduced by IH with no changes in recovery from inactivation. As a consequence, INa "window" current, a strong determinant of intracellular Na+ and Ca2+ concentrations, was significantly increased. The results indicate that increased circulating fatty acids alter INa gating in manners consistent with an increased cardiac excitability and augmentation of intracellular calcium. Moreover, these changes could still be measured after the dogs were left to recover for 12 h after IH perfusion, suggesting lasting changes in INa. Our results indicate that fatty acids rapidly induce cardiac remodeling and suggest that this process may be involved in the development of cardiac dysfunctions associated to insulin resistance and diabetes.

Cyclin B2 suppresses mitotic failure and DNA re-replication in human somatic cells knocked down for both cyclins B1 and B2.

Cyclin-dependent kinase 1 (CDK1) plays a crucial role in establishing metaphase and has also been shown to prevent DNA re-replication. Cyclins B1 and B2 are two known activators of CDK1 operating during mitosis in human cells. Little is known about the specific roles of each of these cyclins in CDK1 activation, but cyclin B2 is thought to play a minor role and to be unable to replace cyclin B1 for mitosis completion. In our study, we found that severe reduction by separate RNA interference of either cyclin B1 or cyclin B2 protein levels results in little or no alteration of the cell cycle and, more specifically, of mitosis progression. In contrast, simultaneous depletion of both B-type cyclins leads to massive accumulation of 4N cells, mitotic failure, premature mitosis exit and DNA re-replication. These defects can be corrected by the ectopic expression of a cyclin B2 resistant to the short hairpin RNA. Altogether, these data show that, in cycling human cells, cyclin B2 can compensate for the downregulation of cyclin B1 during mitosis. They also clearly implicate cyclins B1 and B2 as crucial activators of CDK1 in its biological function of DNA re-replication prevention.

[Group therapy versus individual follow-up in the management of the obese child]. / Comparaison de l'education thérapeutique collective au suivi individuel pour la prise en charge de l'obésité de l'enfant.

OBJECTIVE: To compare the 1-year outcome of obese children managed medically and dietetically in a group setting with those managed individually. PATIENTS AND METHODS: Two hundred and seventy-eight obese children [168 girls and 110 boys; body mass index (BMI) > + 2 SD] were followed by the Department of Pediatrics of the University Hospital of Angers between January 1996 and December 2002 (175 children in a group setting and 103 individually). The group program consisted of 3 monthly sessions of slide shows for groups of 10 children, followed by individual consultations once every 3 months alternating medical and dietetic concerns. The individual program consisted of successive medical and dietetic consultations on the same day once every 3 months. RESULTS: The children were 10.3 +/- 2.9 years old, and their BMI was 5.5 +/- 2.1 SD, with no difference between groups. The drop-out rate (children not returning after the 1st consultation) was 17%, with no difference between groups. The drop-out rate after 1 year was 65% in the group program and 41% in the individual program (p < 0.05). Of the children who were followed for 1 year, 88% of those treated in a group setting had stabilized or reduced their BMI, whereas 74% of the individually-treated children had done so (p < 0.05). CONCLUSION: Among obese children followed for 1 year, group treatment resulted in a greater percentage of stabilization or reduction in BMI than did individual treatment, although the drop-out rate was higher in the group setting. Psychological support and physical activity sessions adapted for obese children would help to maintain motivation in these children.

Stability of the human papillomavirus type 18 E2 protein is regulated by a proteasome degradation pathway through its amino-terminal transactivation domain.

The E2 proteins of papillomaviruses regulate both viral transcription and DNA replication. The human papillomavirus type 18 (HPV18) E2 protein has been shown to repress transcription of the oncogenic E6 and E7 genes, inducing growth arrest in HeLa cells. Using HPV18 E2 fused to the green fluorescent protein (GFP), we showed that this protein was short-lived in transfected HeLa cells. Real-time microscopy experiments indicated that the E2-dependent signal increased for roughly 24 h after transfection and then rapidly disappeared, indicating that E2 was unstable in HeLa cells and could confer instability to GFP. Similar studies done with a protein lacking the transactivation domain indicated that this truncation strongly stabilizes the E2 protein. In vitro, full-length E2 or the transactivation domain alone was efficiently ubiquitinated, whereas deletion of the transactivation domain strongly decreased the ubiquitination of the E2 protein. Proteasome inhibition in cells expressing E2 increased its half-life about sevenfold, which was comparable to the half-life of the amino-terminally truncated protein. These characteristics of E2 instability were independent of the E2-mediated G(1) growth arrest in HeLa cells, as they were reproduced in MCF7 cells, where E2 does not affect the cell cycle. Altogether, these experiments showed that the HPV18 E2 protein was degraded by the ubiquitin-proteasome pathway through its amino-terminal transactivation domain. Tight regulation of the stability of the HPV 18 E2 protein may be essential to avoid accumulation of a potent transcriptional repressor and antiproliferative agent during the viral vegetative cycle.