PubMed Health⌕ Search

Biomedical subjects

E C Larkin

Publications and source records attributed to E C Larkin.

At least 19 recordsLinked to original sources
PubMed1998

PFA-100 system: a new method for assessment of platelet dysfunction.

The PFA-100 system is a platelet function analyzer designed to measure platelet-related primary hemostasis. The instrument uses two disposable cartridges: a collagen/epinephrine (CEPI) and a collagen/ADP (CADP) cartridge. Previous experience has shown that CEPI cartridges detect qualitative platelet defects, including acetylsalicylic acid (ASA)-induced abnormalities, while CADP cartridges detect only thrombocytopathies and not ASA use. In this seven-center trial, 206 healthy subjects and 176 persons with various platelet-related defects, including 127 ASA users, were studied. The platelet function status was determined by a platelet function test panel. Comparisons were made as to how well the defects were identified by the PFA-100 system and by platelet aggregometry. The reference intervals for both cartridges, testing the 206 healthy subjects, were similar to values described in smaller studies in the literature [mean closure time (CT) 132 s for CEPI and 93 s for CADP]. The use of different lot numbers of cartridges or duplicate versus singleton testing revealed no differences. Compared with the platelet function status, the PFA-100 system had a clinical sensitivity of 94.9% and a specificity of 88.8%. For aggregometry, a sensitivity of 94.3% and a specificity of 88.3% were obtained. These values are based on all 382 specimens. A separate analysis of sensitivity by type of platelet defect, ASA use versus congenital thrombocytopathies, revealed for the PFA-100 system a 94.5% sensitivity in identifying ASA users and a 95.9% sensitivity in identifying the other defects. For aggregometry, the values were 100% for ASA users and 79.6% for congenital defects. Analysis of concordance between the PFA-100 system and aggregometry revealed no difference in clinical sensitivity and specificity between the systems (p > 0.9999). The overall agreement was 87.5%, with a Kappa index of 0.751. The two tests are thus equivalent in their ability to identify normal and abnormal platelet defects. Testing 126 subjects who took 325 mg ASA revealed that the PFA-100 system (CEPI) was able to detect 71.7% of ASA-induced defects with a positive predictive value of 97.8%. The overall clinical accuracy of the system, calculated from the area under the ROC curve, was 0.977. The data suggest that the PFA-100 system is highly accurate in discriminating normal from abnormal platelet function. The ease of operation of the instrument makes it a useful tool to use in screening patients for platelet-related hemostasis defects.

Adolescent↗
PubMed1997

Nutritional factors required for alcoholic liver disease in rats.

Decades ago it was suggested that nutritional factors are important in the development of alcoholic liver disease (ALD). However, several models of experimental alcoholism considered that the diets fed to animals were nutritionally adequate, complete and balanced. Therefore, a concept prevailed that the effects observed were due to alcohol per se and that they occurred despite a nutritionally adequate status in the animal. Examination of various models revealed that animals were malnourished because they ingested reduced levels of macro- and micronutrients. Furthermore, they consumed only small amounts of carbohydrate and a high level of unsaturated fat for long periods during the development of ALD. Alcoholic rats show many effects of inadequate nutritional status, such as a slow growth, depressed levels of liver glycogen and pancreatic amylase, enhanced protein degradation and circulating levels of branched-chain amino acids, and increased levels of enzymes involved in gluconeogenesis and alterations in the activities of enzymes related to the metabolism of carbohydrate as compared with controls. Chronic consumption of alcohol did not result in fatty liver, high blood alcohol concentration (BAC) or other observed effects when intake of energy, carbohydrate and other nutrients was increased. Furthermore, pre-existing effects of alcohol consumption, such as fatty liver, BAC and delayed gastric emptying, were reversed in rats receiving increased energy and carbohydrate intakes while continuing alcohol ingestion. Thus, nutritional status of the animal determines the production or prevention of ALD or other effects that were considered to be due to alcohol alone.

Animal Nutritional Physiological Phenomena↗
PubMed1997

Solitary extramedullary plasmacytoma five years after successful cardiac transplantation: case report and review of the literature.

We document the occurrence of a solitary extramedullary plasmacytoma (SEP) in a cardiac transplant patient. The diagnosis of plasma cell malignancy was confirmed by histopathologic and immunohistochemical examination of a nodular skin lesion. A complete systemic evaluation showed no evidence of metastatic disease. The patient was treated locally with radiation therapy (RT), but disseminated multiple myeloma developed 4 months after diagnosis. A variety of tumors have been reported to develop in the cardiac or renal transplant recipient, although plasma cell malignancies are rare. To our knowledge, this is the first reported case of an SEP in an organ transplant recipient.

Cell Nucleus↗
PubMed1997

Treatment-related parameters predicting efficacy of Lym-1 radioimmunotherapy in patients with B-lymphocytic malignancies.

This study was designed to evaluate dosimetric, pharmacokinetic, and other treatment-related parameters as predictors of outcome in patients with advanced B-lymphocytic malignancies. Fifty-seven patients were treated with radiolabeled Lym-1 antibody in early phase trials between 1985 and 1994. Logistic regression and proportional hazards models were used to evaluate treatment parameters for their ability to predict outcome, taking into account patient risk group based on Karnofsky performance status and serum lactic dehydrogenase. The occurrence of a partial or complete response (31 of 57 patients) and development of human antimouse antibody (HAMA) predicted improved survival using a time-dependent proportional hazards model. The final multivariate model for survival with parameters significant at P </= 0.05 included overall response and pretreatment risk group. Although some of the dosimetric and pharmacokinetic parameters were predictive in univariate analyses, only longer half-time of radionuclide in the blood showed any indication of improved prediction beyond that provided by the lactic dehydrogenase/Karnofsky performance status-based risk groups. Splenic volume, splenectomy, and malignant tissue Lym-1 reactivity were not contributory. In this patient group, the effect of radiolabeled Lym-1 treatment as indicated by measurable tumor response was associated with improved survival. Development of HAMA was also associated with improved survival, indicating that concern about HAMA should not preclude exploration of radioimmunotherapy. Although dosimetry has a role in determining safety based on dose to normal organs, when adjusted for baseline clinical features, dosimetric and pharmacokinetic parameters showed limited ability to improve outcome prediction.

Adult↗
PubMed1995

Prognostic factors for radioimmunotherapy in patients with B-lymphocytic malignancies.

The Ann Arbor staging classification has proven less useful in nonHodgkin's lymphoma, because this malignancy is inherently a multifocal disorder. Since 1985, 57 adult patients with advanced B-lymphocytic malignancies that progressed despite standard therapy entered into one of three different therapy trials using radiolabeled Lym-1 antibody. Tumor regression in 31 (54%) of these patients fulfilled conventional requirements for an oncological response to the therapy. To define the role of radioimmunotherapy in B-lymphocytic malignancies better and to find opportunities for improving its therapeutic efficacy, the records of these patients were reviewed to assess the significance of various parameters as prognostic indicators. Twenty-one pretherapy characteristics were evaluated, including age at diagnosis, age at study entry, sex, Karnofsky performance status, prior chemotherapy and radiation therapy, interval since diagnosis, histology, constitutional B symptoms, extranodal malignancy (excluding marrow), bone marrow malignancy, tumor bulk, and circulating malignant cells; blood tests included lymphocyte, granulocyte, platelet, hematocrit, serum lactate dehydrogenase (LDH), interleukin 2 receptor, and human antimouse antibody levels. In the multivariate analysis, LDH and Karnofsky performance status were the parameters that best predicted survival, complete and partial remission, and time to progression; interleukin 2 receptor and LDH best predicted complete remission. These prognostic factors for radioimmunotherapy outcome are consistent with the pretherapy characteristics observed to be significant for chemotherapy.

Adult↗
PubMed1994

Induction of malnutrition in chronic alcoholism: role of gastric emptying.

Epidemiological studies reveal that chronic alcoholics exhibiting liver disease are generally malnourished. Experimental studies unequivocally demonstrate that incidence of malnutrition cannot be avoided in animals fed liquid diets containing high concentrations of alcohol. Furthermore, ingestion of additional amounts of macronutrients by such chronically alcoholic animals prevents or regresses alcohol-induced adverse effects despite a continuous intake of high amounts of alcohol. It is thus apparent that high amounts of alcohol intake and malnutrition are necessary factors to produce adverse effects in chronic alcoholism. The mechanism by which malnutrition manifests in chronic alcoholism is, however, not clear. Recent studies have demonstrated, a) an inverse relationship between alcohol and non-alcohol energy intake and its impact on alcohol-induced effects in chronically alcoholic rats, b) a synergism between malnutrition and high doses of alcohol intake in the induction of alcoholemia, and c) that chronic alcoholemia significantly prolongs the delay in gastric emptying. Data obtained from these studies enable us to hypothesize that abnormal prolongation of gastric emptying in alcoholics with chronic alcoholemia may play a major role in the initiation of macronutrient deficiencies leading eventually to the induction of malnutrition.

Alcoholism↗
PubMed1994

Unsaturated fat and low energy intake induce whereas an increment in energy intake ameliorates fatty liver during prolonged alcohol consumption by rats.

Two groups of rats were fed liquid diets containing 35% of energy as fat and either 36 or 26% of energy as alcohol to examine the effect of fat and energy intake on alcoholic fatty liver production. After 4 wk, five rats in each group were killed for analysis of liver triglyceride concentration, and then the alcohol diets fed to remaining rats were switched. All remaining rats were killed for hepatic triglyceride determination after another 4 wk. Rats initially fed the 36% alcohol diet or those switched to this diet ingested less energy, exhibited alcoholemia and slow growth, and developed fatty livers. Rats initially fed the 26% alcohol diet or those switched to this diet ingested significantly more energy, high amounts of alcohol and fat, exhibited low alcoholemia and faster growth than when they were fed the 36% alcohol diet. Fatty liver was absent in rats fed the 26% alcohol diet but was induced when they were fed the 36% alcohol diet. Fatty liver in rats initially fed the 36% alcohol diet regressed completely when the rats were switched to the 26% alcohol diet. Additional studies employing 36% alcohol diets containing 35% of energy as fat, derived from either corn oil or olive oil, revealed that unsaturated fat and not specifically linoleate plays a role in the induction of fatty liver. Thus, nutritional factors regulate the induction or regression of fatty liver and alcoholemia in alcoholic rats.

Alcoholism↗
PubMed1992

Carbohydrate intake determines pancreatic acinar amylase activity and release despite chronic alcoholemia in rats.

Adverse effects observed in alcoholic rats are often attributed to alcohol per se. Alcoholic liver damage, however, can be avoided by modulating nutritional factors despite high blood alcohol concentrations. Hence, we examined the effect of blood alcohol concentration on pancreatic enzyme activity and release. Three liquid diets containing 36 and 18% of total energy derived from alcohol and protein, respectively, were fed. Each alcohol diet contained 11, 21 or 31% of energy from carbohydrate, and the fat concentration was appropriately adjusted. The control groups of rats (fed an isoenergetic liquid diet without alcohol) and the alcoholic groups of rats were maintained for 2 wk. The three groups of alcoholic rats consumed 13.3 +/- 2.3, 13.3 +/- 2.2 and 13.2 +/- 1.9 g/kg of alcohol daily, and their corresponding blood alcohol levels were 41.5 +/- 4.3, 55.4 +/- 8.9 and 44.6 +/- 2.2 mmol/L. Pancreatic acinar amylase activity in alcoholic rats was proportional to carbohydrate ingested, despite high blood alcohol concentrations; chymotrypsin and trypsin activities were unchanged. Acinar enzyme activities in control rats were similar. Furthermore, cholecystokinin-octapeptide-stimulated amylase release in alcoholic rats corresponded with the amylase concentration in acini, whereas stimulated trypsin output was unaltered in both control and alcoholic rats. These results demonstrate that neither alcohol ingestion nor high blood alcohol concentration affects the activities of pancreatic proteases and that the changes in the activity and release of amylase are related to the intake of carbohydrate.

Alcoholism↗
PubMed1989

Reversal by glucose of pancreatic amylase insufficiency in chronic alcoholic rats.

Carbohydrate consumption regulates pancreatic amylase synthesis in rats. The Lieber-DeCarli 36% alcohol diet employed in chronic alcohol studies and the isocaloric control diet contain 11 and 47% of total calories from carbohydrates, respectively. Young rats fed ad libitum the 36% ethanol diet for 2 weeks obtained 1.2 g/day of carbohydrate, whereas those pair-fed with control diet received 5.8 g/day. Rats fed the 36% ethanol diet and given an intramuscular injection of a solution of 1.5 g of glucose daily for 2 weeks received twofold greater amounts of carbohydrate than saline-injected controls (2.7 versus 1.2 g). These changes in carbohydrate intake produced proportionate changes in pancreatic amylase levels. The secretory responses to cholecystokinin-octapeptide (CCK8) of acini from control and glucose-injected rats were significantly higher compared with those in the saline-injected or noninjected alcohol groups. The blood alcohol levels in glucose-injected rats were markedly reduced compared with other alcohol groups (71.7 versus 274.9 mg/dl) despite similar amounts of ethanol ingestion daily (2.4 g) in the three groups. In vitro experiments with acini from rats fed a nutritionally optimal diet revealed that high pharmacologic concentrations of ethanol, while inducing basal secretion, inhibited CCK8-stimulated amylase secretion. These results indicate that: (a) the amount of alcohol consumption does not correlate with either the levels of blood alcohol or of pancreatic amylase; (b) the carbohydrate availability in rats regulates pancreatic amylase levels despite significant levels of alcohol in blood; (c) blood alcohol levels observed in vivo may not affect synthetic and secretory processes of amylase in pancreatic acini.

Alcoholism↗
PubMed1989

Regulation of pancreatic amylase by dietary carbohydrate in chronic alcoholic rats.

The nutritional adequacy of dietary ingredients is essential for optimal food consumption and growth of animals. Dietary carbohydrate levels regulate pancreatic amylase synthesis. Ethanol diets with 36% of total calories from ethanol and 11% from carbohydrate are nutritionally inadequate, whereas a 26% ethanol diet made isocaloric to the 36% alcohol diet by the addition of maltose-dextrins provides all nutrients in amounts recommended for normal growth. Young rats fed the modified ethanol diet for 3 months consume 101.4 ml of diet daily compared to 66.5 ml by those on the 36% ethanol diet. Increased food consumption results in (a) similar amounts of alcohol consumption (3.6 vs. 3.3 g/day), (b) a threefold enhancement in carbohydrate intake (5.1 vs. 1.7 g/day), and (c) a normal growth rate (6.7 vs. 3.1 g/day). Both the acinar content of amylase (20.2 +/- 0.3 micrograms/mg of protein) and the acinar response to cholecystokinin-octapeptide in 36% ethanol diet-fed rats are significantly reduced compared to those of 26% ethanol diet-fed rats (34.1 +/- 5.6 micrograms/mg of protein). These results confirm (a) the nutritional adequacy of the 26% ethanol diet compared to the 36% ethanol diet, and (b) that carbohydrate inadequacy, and not ethanol consumption per se, is the primary cause of pancreatic amylase insufficiency in chronic alcoholic rats.

Alcoholism↗
PubMed1988

Is malnutrition necessary for the development of alcoholic fatty liver in the rat?

Ingestion of various liquid diets containing 36% calories as ethanol and 35% calories as fat does not provide adequate nutrition to young growing rats. Studies conducted with the aforementioned diets have the effects of malnutrition confounded with those of alcohol administration. Feeding a 26% alcohol liquid diet, which results in adequate nutrient intake with the same level of alcohol ingestion as the 36% alcohol diet, does not result in fatty liver development in the rat. The concept that prevailed for 25 years that fatty liver is caused despite adequate nutrition and hence is due to alcohol alone is therefore erroneous.

Animals↗