Intravascular papillary endothelial hyperplasia (IPEH), or Masson's tumor, is a rare, benign vascular lesion characterized by reactive endothelial proliferation with venous stasis and thrombus. Lesions typically arise in vascular regions of the head and neck or extremities, but involvement of other organ systems has been reported. Clinically, IPEH mimics other benign lesions (hemangiomas) and m...

We report a rare case of intravascular papillary endothelial hyperplasia (IPEH) arising from the upper lip. Pathologically, it consisted of a few lobulated masses lined by an incomplete fibrous capsule of variable thickness which was separated from the surrounding tissue and which partially formed papillary structures bearing fibrous stalks and a single layer of endothelium. The capillary forma...

We report a rare case of intravascular papillary endothelial hyperplasia (IPEH) of the oral mucosa. This neoplasm, known as Masson's tumor, is an unusual vascular lesion of proliferating endothelial cells. It is usually confined to the lumen of preexisting vessels or vascular malformations. The principal significance of IPEH is its microscopic resemblance to angiosarcoma and possible misdiagnos...

The somatostatin analog octreotide was administered to male and female Sprague-Dawley rats by subcutaneous injection for thirteen weeks at 0 (saline control), 0 (placebo control [mannitol and lactic acid; pH 4.2]), 1.25 mg/kg/day and 2.5 mg/kg/day to explore its potential effect on cutaneous vascular morphology. The placebo caused an increase in the incidence of intimal hyperplasia compared to ...

This study examines the growth response of vascular smooth muscle cells following induction of acute hypertension in rats by partial ligation of the abdominal aorta between the renal arteries. Systolic blood pressures proximal to the ligature increased dramatically within 3 days (from 135 +/- 3 to 195 +/- 7 torr) of surgery while pressures distal to the ligature were reduced from control values...

T ransplantation is the accepted treatment of end-stage organ failure. The introduction of cyclosporine (CsA) in the early 1980s greatly improved the outcome of solid organ transplantation, with an increase in 3-year survival from almost 40% to 70%. Substantial advances in the development of additional immunosuppressants have allowed transplant physicians to more specifically modulate the immun...

The P2Y receptor family is a class of G protein-coupled receptors activated primarily by adenosine triphosphate (ATP), diphosphate (ADP), uridine (UTP) and (UDP). P2Y12 expressed on platelets which mediates platelet aggregation morphological changes. At the same time, during process vascular remodeling atherosclerosis, ADP can also promote migration proliferation smooth muscle endothelial cells...

Complex lymphatic anomalies (CLAs) are sporadically occurring diseases caused by the maldevelopment of vessels. We and others recently reported that somatic activating mutations in KRAS can cause CLAs. However, mechanisms which CLAs poorly understood. Here, we show G12D expression endothelial cells (LECs) during embryonic development impairs formation lymphovenous valves causes enlargement demo...