Mitochondrial cytopathy has been associated with modifications of lipid metabolism in various situations, such as the acquisition of an abnormal adipocyte phenotype observed in multiple symmetrical lipomatosis or triglyceride (TG) accumulation in muscles associated with the myoclonic epilepsy with ragged red fibers syndrome. However, the molecular signaling leading to fat metabolism dysregulation in cells with impaired mitochondrial activity is still poorly understood. Here, we found that preadipocytes incubated with inhibitors of mitochondrial respiration such as antimycin A (AA) accumulate TG vesicles but do not acquire specific markers of adipocytes. Although the uptake of TG precursors is not stimulated in 3T3-L1 cells with impaired mitochondrial activity, we found a strong stimulation of glucose uptake in AA-treated cells mediated by calcium and phosphatidylinositol 3-kinase/Akt1/glycogen synthase kinase 3 ␤ , a pathway known to trigger the translocation of glucose transporter 4 to the plasma membrane in response to insulin. TG accumulation in AA-treated cells is mediated by a reduced peroxisome proliferator-activated receptor ␥ activity that downregulates muscle carnitine palmitoyl transferase-1 expression and fatty acid ␤ -oxidation, and by a direct conversion of glucose into TGs accompanied by the activation of carbohydrate-responsive element binding protein, a lipogenic transcription factor. Taken together, these results could explain how mitochondrial impairment leads to the multivesicular phenotype found in some mitochondria-originating diseases associated with a dysfunction in fat metabolism. The role of mitochondria in lipid homeostasis has been strongly emphasized in recent studies focusing on mitochondrial respiratory deficiency. Indeed, chronic mitochondrial dysfunction can lead to diseases characterized by lipid metabolism disorders and pathological triglyceride (TG) accumulation in several cell types (1-3). Genetic mitochondrial pathologies usually result from point mutations or deletions in mitochondrial DNA that finally impair oxidative phosphorylation capacity (4). Interestingly, some mitochondrial disorders affect lipid-metabolizing tissues such as muscular and adipose tissues. For example, the myoclonic epilepsy with ragged red fibers (MERRF) syndrome, commonly caused by a point mutation in the mitochondrial tRNA Lys -encoding gene (A8344G), is associated with myopathy, TG accumulation in muscles (5), and, in some cases, multiple symmetrical lipomatosis (MSL) (2, 6). MSL is a pathology characterized by the formation of lipomas containing abnormal white adipocytes smaller than normal adipocytes showing a multivesicular phenotype (1, 2, 7). Moreover, biochemical analyses have shown that cytochrome c oxidase activity is impaired in muscles from patients with MSL (8), supporting the fact that the disease is linked to mitochondrial dysfunction (6, 9). The role of mitochondria in the lipid metabolism of white adipose tissue was also strengthened in the pathogenesis of Abbreviations: AA,...

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We present a very rare case of a neonatal multiple haemangiomatosis with a cystic interventricular cardiac haemangioma. An anechoic cyst of 10 mm of diameter, located in the superior third of the interventricular septum was found by foetal echocardiography at 30 weeks of pregnancy. The baby was born at 39 weeks of pregnancy and the skin was covered with multiple purple cutaneous haemangiomas. As neonatal haemangiomatosis may be associated with visceral haemangiomas, the diagnosis of cardiac haemangioma was considered and transthoracic echocardiography revealed a translucent cyst consistent with this diagnosis. At 6 months of age, the cardiac mass was barely visible and most cutaneous lesions had regressed without treatment. Cardiac haemangiomas must be considered in the diagnosis of cystic masses, and the present case emphasizes the tendency towards spontaneous regression of these lesions.

The Visible-Infrared SASE Amplifier (VISA) undulator [1] consists of four 99cm long segments. Each undulator segment is set up on a pulsed-wire bench, to characterize the magnetic properties and to locate the magnetic axis of the FODO array [2]. Subsequently, the location of the magnetic axis, as defined by the wire, is referenced to tooling balls on each magnet segment by means of a straightness interferometer. After installation in the vacuum chamber, the four magnet segments are aligned with respect to themselves and globally to the beam line reference laser. A specially designed alignment fixture is used to mount one straightness interferometer each in the horizontal and vertical plane of the beam. The goal of these procedures is to keep the combined rms trajectory error, due to magnetic and alignment errors, to 50µm.