PubMed Health⌕ Search

Biomedical subjects

J Cronin

Publications and source records attributed to J Cronin.

33 records · Page 2Linked to original sources
PubMed1991

A prospective analysis of cholestasis in infants supported with extracorporeal membrane oxygenation.

Cholestasis develops in many infants supported with extracorporeal membrane oxygenation. We prospectively investigated the role of hemolysis and di-(2-ethylhexyl) phthalate exposure in the development of this cholestasis. Both di-(2-ethylhexyl) phthalate levels and hemolysis, as measured by maximum free hemoglobin, were significantly (p less than 0.025) associated with the degree of cholestasis. Other clinical and laboratory factors that may contribute to cholestasis were also investigated and not found to be related to the degree of cholestasis. We speculate that hemolysis during extracorporeal membrane oxygenation support produces a large bilirubin load whose excretion is inhibited by mechanisms similar to the inspissated bile syndrome and/or by di-(2-ethylhexyl) phthalate. This would result in a predominantly direct hyperbilirubinemia with little evidence of hepatocellular or canalicular injury.

Analysis of Variance↗
PubMed1988

Chronic seizures and collateral sprouting of dentate mossy fibers after kainic acid treatment in rats.

Kainic acid (KA) injections destroy hippocampal pyramidal cells, induce recurrent collateral sprouting of the hilar mossy fibers (MFs), and lead to chronic seizures. In the present study, rats were injected systemically with KA (14 mg/kg) to determine whether the subsequent occurrence of seizures was correlated with MF sprouting, as indicated by Timm's staining of proximal dendrites. At 4 weeks, 56% of the KA-treated rats had MF sprouting in the temporal (ventral) hippocampus, and 52% had shown seizures between 10 and 28 days. Both seizures and sprouting were seen in 32% of the treated animals. While Timm's staining of MFs in the inner molecular layer was not directly correlated with seizure scores, animals which exhibited chronic seizures had significantly more sprouting than animals which did not have seizures.

Animals↗
PubMed1986

Criteria for extracorporeal membrane oxygenation in a population of infants with persistent pulmonary hypertension of the newborn.

Extracorporeal membrane oxygenation (ECMO) has been available since 1975 as a therapy of last resort to provide adequate oxygenation for term infants with acute lung disorders that do not respond to maximal medical therapy. Virtually all term infants with serious lung disease have persistent pulmonary hypertension of the newborn (PPHN) characterized by significant right-to-left shunting of blood and severe diffusion defects manifested as increased alveolar-arterial oxygen gradients (AaDO2). Criteria for initiation of ECMO therapy have been developed in several institutions but at the present time there are no universal criteria applicable to all infants with PPHN. We have attempted to establish entry criteria that may be used for different populations of infants with PPHN. Based on a retrospective review of 30 infants with PPHN in our institution, we have defined standards of maximal medical therapy. An alveolar-arterial oxygen difference (AaDO2) of greater than or equal to 610 for 8 hours has been shown to be associated with 79% mortality in this population. This AaDO2/time interval is established as a major criterion for institution of extracorporeal membrane oxygenation.

Carbon Dioxide↗
PubMed1979

Biomathematical models of schizophrenia.

This paper summarizes the work of developing and analyzing a mathematical model of schizophrenia. First the psychological and physiological studies of patients with periodic catatonia made by R. R. Gjessing are briefly described. Then a mathematical model, which is based on Gjessing's work and consists of a set of nonlinear ordinary differential equations, is derived. Gjessing showed that there was a periodic change in the basal metabolic rate associated with a periodic change in the symptoms of catatonia. This suggests a study of the thyroid control system, and since the thyroid control system is a negative feedback system, previous engineering studies are followed and a system of ordinary differential equations is used as a model. The first such model was due to Danziger and Elmergreen, and their model and improvements of their model are described. Then the models are analyzed qualitatively and the mathematical results are interpreted medically. Solutions of the system of differential equations corresponding to a stable set of symptoms in the schizophrenic patients, solutions corresponding to periodic patterns of symptoms (periodic catatonia), and solutions corresponding to random or unpredictable patterns of symptoms are obtained. The model suggests that since certain parameters are varied, various types of solutions and hence various patterns of symptoms are obtained. There are a number of unresolved questions in this study, and these problems are discussed in detail as they arise.

Humans↗
PubMed1978

Coupling polylysine to glass beads for plasma membrane isolation.

Solid glass beads for use in isolating cell membranes were coated with a stable, covalently attached layer of polylysine. The optimal conditions for coating the bead surface were established and the beads were tested by measuring the attachment of human erythrocyte plasma membranes. When compared to other beads, such as those with absorbed polylysine or protamine, none retained red-cell membranes as well as glass beads with covalently linked polylysine.

Adsorption↗