Preexisting Vascular Lesions Research Articles

Platelets in diabetes: the role in the hemostatic regulation in atherosclerosis.

Vascular diseases and related complications still represent the main cause of death in diabetic patients. Neuropathy, nephropathy, retinopathy, and disturbed nutritive tissue perfusion may result from reduced capillary microcirculation. These disturbances are diabetes specific. Macroangiopathy does not differ structurally from atherosclerotic lesions of nondiabetic subjects, but leads to accelerated cerebral, coronary, and peripheral artery disease. Occurrence of life-terminating thrombotic events, which are superimposed on those vascular lesions, are increased. Thus, morbidity and mortality of diabetics depend mainly on vascular complications. Normal blood flow is a prerequisite of adequate organ perfusion and results from vasomotion, plasma components, corpuscular blood elements, vascular architecture, and the undisturbed interaction of these components at the endothelial interface. Functional thromboresistance of the endothelial layer is reduced in the diabetic state. Increased intravascular thrombin generation, reduced fibrinolytic potential, and hyperactive platelets lead to a prethrombotic state. This thrombotic diathesis increases the permanent danger of acute flow interruption. Activated platelets operate by three mechanisms: (1) Microembolization of the capillaries; (2) local progression of preexisting vascular lesions by secretion of constrictive, mitogenic, and oxidative substances; (3) trigger of the prognosis-limiting arterial thrombotic event. We were able to show that the increased functional properties of diabetic platelets result from the primary release of larger platelets with enhanced thromboxane formation capacity and increased numbers of functional glycoprotein receptors GPIb and GPIIb/IIIa, which are synthesized in the megakaryocytes. The megakaryocyte-platelet system is turned on in diabetes mellitus. It could be demonstrated with the Duesseldorf III method of flow cytometric activation marker testing (CD62, CD63, thrombospondin) that predominantly large platelets circulate in an activated state in diabetes mellitus.(ABSTRACT TRUNCATED AT 250 WORDS)

Oral intravascular papillary endothelial hyperplasia

Intravascular papillary endothelial hyperplasia (IPEH) is usually a cutaneous lesion thought to represent a peculiar manifestation of an organizing thrombus. IPEH can be subdivided into a pure form that occurs within a dilated vascular space and a mixed form that appears as a focal change within a preexisting vascular lesion, such as hemangioma. The principle significance of the lesion lies in the fact that it may be mistaken for angiosarcoma. Oral lesions are uncommon and the present paper reports on 16 new cases of oral IPEH, analyzing their clinical and histomorphologic features. Histologically, 11 lesions appeared in a pure form and 5 lesions in a mixed form. Thrombi were detected in all but one case. The most common location was the lip, followed in decreasing frequency by the tongue and buccal mucosa. Local excision was the treatment of choice.

CEREBROVASCULAR COMPLICATIONS OF PREGNANCY

Summary 1. Cerebrovascular complications are frequently associated with toxemia of pregnancy, greatly increase the mortality rate, and often pass unrecognized. 2. These complications may manifest themselves as hemorrhage or enc.ephalomalacia, usually depend on some pre-existing vascular lesion not peculiar to pregnancy, and therefore are not to be classified among the true toxemas. 3. In the absence of such chronic vascular disease, it is suggested that temporary vasospasm may result in distal softening with or without hemorrhage. 4. Careful neurologic examination of the pregnant hypertensive patient is mandatory if these complications are to be discovered. This is an obvious prerequisite to the institution of adequate treatment, which may improve the generally unfavorable prognosis.

Cerebrovascular Complications of Pregnancy

Summary 1. Cerebrovascular complications are frequently associated with toxemia of pregnancy, greatly increase the mortality rate, and often pass unrecognized. 2. These complications may manifest themselves as hemorrhage or enc.ephalomalacia, usually depend on some pre-existing vascular lesion not peculiar to pregnancy, and therefore are not to be classified among the true toxemas. 3. In the absence of such chronic vascular disease, it is suggested that temporary vasospasm may result in distal softening with or without hemorrhage. 4. Careful neurologic examination of the pregnant hypertensive patient is mandatory if these complications are to be discovered. This is an obvious prerequisite to the institution of adequate treatment, which may improve the generally unfavorable prognosis.