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R I Lewy

Publications and source records attributed to R I Lewy.

14 recordsLinked to original sources
PubMed1996

Laboratory studies in breast implant patients: ANA positivity, gammaglobulin levels, and other autoantibodies.

Silicone polymers when used in augmentation prosthesis in breast surgery have been associated in the medical literature with various systemic clinical manifestations and abnormal laboratory testing suggestive of an atypical autoimmune disease. The most frequently cited abnormal test result is the antinuclear antibody. The literature regarding this test is reviewed in general, and then specific previous studies analyzed. The present study then compares the rate of positive antinuclear antibody tests in a case series of 3380 breast implant recipients with historical normal controls, and finds a six-fold increase in relative risk of a positive test. Analysis of the data show that this increased tendency is at least partially a function of duration of implant exposure to a significant degree (p < 0.001), and the same data shows it is not patient age related. Possible explanations of this phenomenon are discussed, including animal studies suggesting that silicone serves as an adjuvant, and therefore might have an effect on immune tolerance in the subject population.

Antibodies, Antinuclear↗
PubMed1995

Norplant.

Explore the source record for details and available documents.

Adolescent↗
PubMed1983

Role of thromboxanes in vasotonic versus vaso-occlusive angina.

We used a validated radioimmunoassay to examine plasma thromboxane B2 (TxB2) levels in 6 consecutive vasotonic angina (VA) patients, 14 patients with fixed, occlusive coronary artery (VO) disease and 9 healthy volunteers. In the latter groups, basal TxB2 release was absent. However, all 6 VA patients showed basal release. In one, sustained levels of up to 12 pmol/ml over 2 months of clinical instability were found. Daily aspirin rendered TxB2 undetectable with clinical improvement. In a second patient, angina coincided with up to 14 pmol/ml of TxB2 in peripheral blood, and myocardial infarction produced still further increases. The 14 VO patients were then studied by rapid atrial pacing to detect TxB2 release coinciding with pacing-induced angina and myocardial lactate production. All demonstrated significant occlusive disease (2.5 critical lesions per patient). Blood was taken simultaneously from coronary sinus (CS) and brachial artery (BA) catheters for lactate and TxB2 analysis before, immediately after and 10 min after pacing-induced ischemia. Lactate extraction fell from 29.3 +/- 3.7 per cent to -21.1 +/- 12.8 per cent to -74.3 +/- 20.3 per cent during pacing (all p less than 0.01) but was normal in 10 min (25.1 +/- 3.55). CS TxB2 rose from 18 per cent to 204 per cent of control during pacing but was absent after 10 min. BA TxB2 rose from 40 per cent to 132 per cent of control during and after pacing, but was absent after 10 min (p less than 0.05). In VA, TxB2 is uniquely, continuously present in peripheral blood and levels rise further during symptomatic intervals and myocardial infarction. In VO, even CS TxB2 is absent at rest, and rises less rapidly than in VA, even during pacing-induced ischemia. Although antiplatelet agent will block all TxB2 release even in VO, their clinical potential seems greatest in VA.

Angina Pectoris↗
PubMed1980

Effect of elevated plasma-free fatty acids on thromboxane release in patients with coronary artery disease.

Increases in endogenous free fatty acids (FFA) induced by several stimuli are associated with increases in platelet aggregates and platelet factor 4 in man. To determine if thromboxane (TxB) release is also an associated event, we measured plasma FFA and TxB2 levels before and 5 min after bolus injection of 2,500 U of heparin prior to coronary arteriography in 27 patients with angina. Significant increases in FFA occurred in all patients (p less than 0.02) and those with critical lesions (p less than 0.01), while TxB2 levels also rose (p less than 0.02, p less than 0.05, respectively). However, linear regression showed increases in FFA and TxB2 were independent. The observed TxB2 release may be due to lipolysis-induced exposure of vascular collagen or direct inhibition of platelet adenylate cyclase by heparin.

Aged↗
PubMed1979

Leukemia in patients with acquired idiopathic sideroblastic anemia: an evaluation of prognostic indicators.

The initial clinical and laboratory data of 25 patients with acquired idiopathic sideroblastic anemia (AISA) were analyzed. Criteria for accepting the diagnosis were hyperferremia, ringed marrow sideroblasts, ineffective erythropoiesis, and exclusion of associated hematologic disorders. The findings of a mean age at onset of 70 years, increased mean corpuscular volume, relative neutropenia; and occasional splenomegaly at diagnosis corresponded with previous reports. During the followup for a median period of 32 months, 6 patients (25%) transformed to acute myelogenous or myelomonocytic leukemia after widely variable intervals. The initial data base of these patients was compared to that of the remaining 19 patients in order to isolate predictive features. Only a lesser degree of hyperferremia (P less than 0.001) made the group going on to leukemia distinctive. The median survival of these patients was 20 months. The median survival of 19 patients not developing leukemia was 72 months for males and 42 months for females. Hemochromatosis was diagnosed in four patients and was a primary or associated cause of death in three. Analysis of the transfusion history suggested that intrinsic iron leading was a major factor in these patients. We conclude that leukemic transformation in AISA is a common, poorly predictable event which required lengthy followup for detection. Hemochromatosis in AISA occurs frequently and shortens the median survival.

Adult↗
PubMed1979

19-Hydroxy-prostaglandin E and infertility in human males.

We measured the content of 19-hydroxy-prostaglandin E (19-OH-PGE) and prostaglandin E (PGE) in the semen of 10 infertile males by alkaline dehydration, thin layer chromatographic separation and ultraviolet spectrophotometry. 7 fertile males were also studied. In both groups the content of seminal 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) also was measured by thin layer chromatographic separation and highly specific radioimmunoassay. The amounts of 19-OH-PGE and PGE were significantly lower (p < .02, p < .05) in the infertile group than the fertile group. Differences in mean seminal 6-keto-F1 alpha were not significant. The uterine stimulatory actions of 19-OH-PGE demonstrable in the monkey may apply to fertility in man.

6-Ketoprostaglandin F1 alpha↗