Platelet derived growth factor regulates ABCA1 expression in vascular smooth muscle cells

AbstractThe ATP-binding cassette transporter A1 (ABCA1) regulates lipid efflux from peripheral cells to High-density lipoprotein. The platelet-derived growth factor (PDGF) is a potent mitogen that enables vascular smooth muscle cells to participate in atherosclerosis. In this report, we showed that PDGF suppressed endogenous expression of ABCA1 in cultured vascular smooth muscle cells. Exposure of CRL-208 cells to PDGF elicited a rapid phosphorylation of a kinase downstream from PI3-K, Akt. The constitutively active form of both p110, a subunit of PI3-K, and Akt inhibited activity of the ABCA1 promoter. In conclusion, PI3-K-Akt pathways participate in PDGF-suppression of ABCA1 expression

Xanthogranuloma of the intrasellar region presenting in pituitary dysfunction: a case report

<p>Abstract</p> <p>Introduction</p> <p>Differentiation of cystic mass lesions of the sellar and parasellar regions may pose a diagnostic dilemma for physicians, neurosurgeons, radiologists and pathologists involved in treating patients with these entities. A considerable number of tumors previously identified as craniopharyngiomas may, in fact, have been xanthogranulomas. We report a case of pituitary dysfunction caused by xanthogranuloma of the intrasellar region.</p> <p>Case presentation</p> <p>A 47-year-old man of Japanese descent presented to our institution with a tumor located exclusively in the intrasellar region which manifested as severe hypopituitarism. MRI revealed a clearly defined intrasellar mass that was heterogeneously hyperintense on T1-weighted images and markedly hypointense on T2-weighted images. We preoperatively diagnosed the patient with Rathke's cleft cyst or non-functioning pituitary adenoma. Although the tumor was completely removed using a transsphenoidal approach, the improvement of the patient's endocrine function was marginal, and continued endocrine replacement therapy was needed. Postoperatively, a histological examination revealed the tumor to be a xanthogranuloma of the intrasellar region. His visual field defects and headache improved.</p> <p>Conclusion</p> <p>Because diagnosis depends on surgical intervention and xanthogranulomas of the intrasellar region are very rare, the natural history of xanthogranuloma is still unknown. Therefore, this entity is difficult to diagnose preoperatively. We suggest that xanthogranuloma should be included in the differential diagnosis, even in the case of sellar lesions, to formulate appropriate postoperative management and improve endocrine outcomes.</p

Chronic Haemolytic Anemia and Splenomegaly in a Patient with an Isolated Adrenocorticotropin Deficiency

Herein we describe a case of a 56-years old patient presented with general malaise, anorexia and progressive weight loss for about 5years associated recently with diarrhoea and repeated syncopal attacks for 1month. On admission, he had splenomegaly and his laboratory studies showed macrocytic hyperchromic haemolytic anemia [Hb = 9.4g/dl] and a significant hyponatremia [Na + = 111mmol/l]. Endocrinological evaluation revealed an isolated adrenocorticotropin deficiency (IAD) with a manifest hypoaldosteronism. On treatment with cortisone, both anemia and hyponatremia (but not splenomegaly) were markedly improved. Our case may represent an evidence for the pathogenesis of erythropoietic dysfunction in patients of adrenocortical insufficiency

Unique Dispersal of the Changjiang-Diluted Water Plume in the East China Sea Revealed from Satellite Monitoring of Colored Dissolved Organic Matter (CDOM)

The optical properties of colored dissolved organic matter (CDOM) in the Changjiang (Yangtze River) plume water were investigated during the summer of 2009 and 2010. The absorption coefficient of CDOM at 325 nm (aCDOM) increased inversely with decreasing sea-surface salinity (SSS), implying that aCDOM can be used as a natural tracer of Changjiang-diluted water (CDW). This aCDOM vs. SSS relationship, however, differed between 2009 and 2010. For mapping the CDW plume, the aCDOM was retrieved from an ocean-color satellite. Values of SSS were also derived from the satellite-retrieved aCDOM using field-based SSS vs. aCDOM relationships. Satellite observations revealed the temporary variable eastward extension of a high aCDOM, low SSS CDW plume in the central East China Sea (ECS) during the summer. The CDW plume during the summer of 2010 extended southeastward from the mouth of the Changjiang (Yangtze River) to almost 26°N. Moreover, the branch of this southeastward CDW plume was seen to extend northeastward to the eastern ECS where the Kuroshio Current flows northeastward along the shelf break. Subsequently, this branch was distributed around southern Kyushu. Satellite observations revealed this unique dispersal of the CDW plume, which illustrates that the aCDOM and SSS from ocean-color satellite data are useful for monitoring the dispersal of this river-water plume