Norman E. Levan

Diabetic dermangiopathy.A spectrum including pigmented pretibial patches and necrobiosis lipoidica diabeticorum.

Necrobiosis Lipoidica Diabeticorum (NLD) and Pigmented Pretibial Patches (PPP) are characterized by their association with diabetes mellitus, by their pretibial predilection, and by vascular alterations compatible with diabetic microangiopathy. Despite differences in the gross and microscopic morphology, both may be considered part of a spectrum of cutaneous lesions for which the term diabetic dermangiopathy is suggested.

Peripheral Blood Flow in the Neonate. 1. Changes in Total, Skin, and Muscle Blood Flow with Gestational and Postnatal Age

Summary: Total peripheral blood flow and blood flow through the skin and muscle were measured in the calf with an electrocapacitance plethysmograph with counter pressure in a group of 62 “well” newborn infants (birth weight, ≤3500 g). Blood pressure in the contralateral leg was measured with an Arteriosonde 1010, and peripheral vascular resistance was calculated as mean blood pressure (mm Hg) divided by blood flow (ml per 100 ml tissue per min). The results show that total peripheral blood flow and blood flow through the skin and muscle correlated inversely with increasing birth weight and gestational age. Postnatally, total blood flow and blood flow through the skin and muscle decreased gradually during the first 7 days of life and in the rest of the neonatal period. Peripheral vascular resistance and resistance in the skin and muscle correlated directly with increasing birth weight and gestational age. Postnatally, peripheral vascular resistance and resistance in the skin and muscle increased during the first 7 days of life and the neonatal period.Speculation: The lower peripheral vascular resistance and hypervascularity in the skin of immature infants account for higher peripheral blood flow in these infants. The associated increment in peripheral vascular resistance account for the gradual decrement in periphera1 blood flow with advancing maturity and postnatal age. Differences in change of total peripheral blood flow and blood flow in the skin and muscle in relation to change in state, environment, and biochemical alterations need to be studied.

Lucio's phenomenon: an immune complex deposition syndrome in lepromatous leprosy.

Abstract Lucios phenomenon is an acute lepra reaction in diffuse lepromatous leprosy characterized by cutaneous infarctions secondary to a necrotizing vasculitis. Five cases of Lucios phenomenon were studied to elucidate the pathogenesis of this complication of leprosy. Direct immunofluorescent studies of the lesions revealed the presence of deposits of complement and immunoglobulin in the walls of dermal blood vessels and in perivascular areas. The deposits were eluted when the cryostat sections of skin were incubated with an acidic buffer. Cryoglobulins of the “mixed type” containing IgG, IgM, IgA, C3, and C1q were found in the serum of four patients. Analysis of the cryoglobulins revealed an enrichment of rheumatoid factor activity in the cryoprecipitate over that of the serum. Immune complexes were found in the serum of all patients. Hypocomplementemia was observed in one patient. These data suggest that Lucios phenomenon is mediated by the deposition of immune complexes in dermal blood vessels.

Changes in Blood Flow in the Skin and Muscle with Phototherapy

Extract: The electrocapacitance plethysmograph with local counterpressure was adapted for measurement of total blood flow and blood flow through the muscle and skin in 20 icteric preterm infants. Measurements were recorded from each infant, before and during phototherapy. In 10 infants in study I, the incubator was set to maintain skin temperature of 36.5° initially and during phototherapy and no attempt was made to alter the incubator settings. Total blood flow was found to increase by a mean of 116% due primarily to increased skin blood flow (224%) and to a lesser extent, muscle blood flow (35%). Concomitant increases in heart rate, respiration rate, skin and incubator temperature were found, but no change was observed in rectal temperature. In 10 infants in study II, the skin temperature was kept constant at 36.5° before and during phototherapy by adjustment of incubator temperature. Significant increases, but of lesser magnitude, were observed in skin (52%) and total blood flow (37%), whereas muscle blood flow remained unchanged. Rectal temperature fell by a mean of 0.6° and respiration rate and heart rate remained unchanged.Speculation: During phototherapy both an increase in surface temperature and the direct effect of light results in augmentation of total blood flow. Increasing skin temperature appears to affect blood flow in both skin and muscle, whereas the direct effect of light from phototherapy lamps appears to affect skin blood flow only and to a lesser degree. The augmentation in skin blood flow should increase the efficiency of phototherapy. However, in small or sick infants the metabolic demands due to increasing temperature may outweigh any benefit from increasing blood flow.

Changes in the capillary filtration coefficient of cutaneous vessels in women with premenstrual tension

Abstract In an attempt to explain excessive fluid retention, the most common feature in the syndrome of subjective and objective changes called premenstrual tension, we investigated changes in the peripheral circulations of women with this complaint. To obtain evidence on the vascular systems ability to maintain a constant circulating fluid volume, we measured capillary filtration coefficient in the forearm. Women who complained of premenstrual distress showed a significant change in capillary filtration coefficient (CFC) during the month; the lowest CFC values were found immediately after the onset of the menses; the highest values occurred just before the beginning of menstruation. In a group of women who claim to be completely free of the complaint, the CFC was uniform throughout the cycle.

BLOOD FLOW AND VENOUS DISTENSIBILITY IN THE UPPER AND LOWER EXTREMITIES OF NEWBORN INFANTS

Abstract. The electrocapacitance plethysmograph was utilized to measure peripheral blood flow and venous distensibility in 17 newborn infants and 20 adults. Measurements were made in the upper and lower extremities in each subject under identical environmental conditions. Blood flow in the forearm and calf were found to be significantly higher in infants than adults. In infants there were no significant differences in the blood flow between the upper and lower extremities. In contrast, in the adults, the blood flow was significantly higher in the upper than in the lower extremities. Similarly, venous distensibility was observed to be higher in infants than in adults. While no significant differences were observed in the venous distensibility between the upper and lower extremities in infants, the venous distensibility was found to be higher in the forearm than in the leg in adults.

Melanoma. Associated antigens in benign melanocytic disorders.

ABSTRACT: Three instances of depigmentation occurring in children with congenital large nevocytic nevi are reported. Serologic studies for tumor‐associated antigens to melanoma were performed by indirect immunofluorescence and complement fixation on these patients and others with benign melanocytic disorders. Positive reactivity in several children was observed. The small numbers studied and lack of uniformity of other testing methods leave open the question of relevanc of such reactivity to malignant conversion or protection in congenital nevi.