Biomedical subjects

Eun-Jeong Lee

Publications and source records attributed to Eun-Jeong Lee.

5 recordsLinked to original sources

PubMed2007

Cognitive phenotypes in temporal lobe epilepsy.

The objective of this study is to determine if distinct cognitive phenotypes could be identified in temporal lobe epilepsy. Epilepsy patients (n = 96) and healthy controls (n = 82) underwent comprehensive neuropsychological assessment. Adjusted (age, gender, and education) test scores for epilepsy subjects were grouped into cognitive domains (intelligence, language, visuoperception, immediate and delayed memory, executive function, and cognitive/psychomotor speed). Cluster analysis revealed three distinct cognitive profiles types: (1) minimally impaired (47% of subjects); (2) memory impaired (24%); and (3) memory, executive, and speed impaired (29%). The three cluster groups exhibited different patterns of results on demographic, clinical epilepsy, brain volumetrics, and cognitive course over a 4-year interval. The specific profile characteristics of the identified cognitive phenotypes are presented and their implications for the investigation of the neurobehavioral complications of epilepsy are discussed.

Adolescent↗

PubMed2006

New insights into the passive force enhancement in skeletal muscles.

The steady-state isometric force following active stretching of a muscle is always greater than the steady-state isometric force obtained in a purely isometric contraction at the same length. This phenomenon has been termed "residual force enhancement" and it is associated with an active and a passive component. The origin of these components remains a matter of scientific debate. The purpose of this work was to test the hypothesis that the passive component of the residual force enhancement is caused by a passive structural element. In order to achieve this purpose, single fibers (n=6) from the lumbrical muscles of frog (Rana pipiens) were isolated and attached to a force transducer and a motor that could produce computer-controlled length changes. The passive force enhancement was assessed for three experimental conditions: in a normal Ringer's solution, and after the addition of 5 and 15mM 2,3-butanedione monoxime (BDM) which inhibits force production in a dose-dependent manner. If our hypothesis was correct, one would expect the passive force enhancement to be unaffected following BDM application. However, we found that increasing concentrations of BDM decreased the isometric forces, increased the normalized residual force enhancement, and most importantly for this study, increased the passive force enhancement. Furthermore, BDM decreased the rate of force relaxation after deactivation following active stretching of fibers, passive stretching in the Ringer's and BDM conditions produced the same passive force-sarcomere length relationship, and passive force enhancement required activation and force production. These results led to the conclusion that the passive force enhancement cannot be caused by a structural component exclusively as had been assumed up to date, but must be associated, directly or indirectly, with cross-bridge attachments upon activation and the associated active force.

Animals↗

PubMed2006

Acute myopathy associated with liver cirrhosis.

AIM: Many cirrhotic patients have muscular symptoms and rhabdomyolysis. However, myopathy associated with liver cirrhosis has not been established as a disease entity. We evaluated the clinical significance of acute myopathy associated with liver cirrhosis. METHODS: We retrospectively reviewed the medical records of 5440 cirrhotic patients who had been admitted to Gyeongsang National University Hospital from August 1997 to January 2003. Among these, 99 developed acute myopathies, and they were analyzed with respect to clinical and laboratory parameters, and outcomes. RESULTS: The Child-Pugh classification at the time of myopathy onset was A in 3(3.1%) cases, B in 33(33.3%), and C in 63 (63.6%). Infection was identified as the most predisposing factor to myopathy. Fifty percent of 18 idiopathic cases who were tested for influenza antibody were positive. Forty-two of the 99 cases were complicated by acute renal failure, and 25 (59.5%) of these expired. Apart from 6 cases lost to follow-up, 64 of 93 recovered, giving a mortality rate of 31.2%. Mortality was higher in Child-Pugh class C than in B or A. CONCLUSION: Acute myopathy can develop as a serious complication in liver cirrhosis. Its frequency, severity and mortality depend on underlying liver function, and are higher in decompensated liver cirrhosis. Influenza should be considered as an etiologic factor in idiopathic cases. It is proposed that acute myopathy associated with liver cirrhosis be called 'hepatic myopathy', and that careful monitoring for hepatic myopathy is necessary in the patients with advanced liver cirrhosis.

Acute Disease↗

PubMed2005

Modulation of passive force in single skeletal muscle fibres.

In this study, we investigated the effects of activation and stretch on the passive force-sarcomere length relationship in skeletal muscle. Single fibres from the lumbrical muscle of frogs were placed at varying sarcomere lengths on the descending limb of the force-sarcomere length relationship, and tetanic contractions, active stretches and passive stretches (amplitudes of ca 10% of fibre length at a speed of 40% fibre length/s) were performed. The passive forces following stretch of an activated fibre were higher than the forces measured after isometric contractions or after stretches of a passive fibre at the corresponding sarcomere length. This effect was more pronounced at increased sarcomere lengths, and the passive force-sarcomere length relationship following active stretch was shifted upwards on the force axis compared with the corresponding relationship obtained following isometric contractions or passive stretches. These results provide strong evidence for an increase in passive force that is mediated by a length-dependent combination of stretch and activation, while activation or stretch alone does not produce this effect. Based on these results and recently published findings of the effects of Ca2+ on titin stiffness, we propose that the observed increase in passive force is caused by the molecular spring titin.

Animals↗

PubMed2005

Sugar responsible and tissue specific expression of a gene encoding AtCIPK14, an Arabidopsis CBL-interacting protein kinase.

Expression of AtCIPK14 (an Arabidopsis CBL-interacting protein kinase 14) was induced by metabolic sugars. Two A/T-rich sequences similar to elements involved in sugar-inducible expression of other genes were found within the -183 bp 5' region of the AtCIPK14 promoter that was responsible for the sugar induction. Histochemical analysis using a reporter gene indicated vascular-specific expression of AtCIPK14.

Arabidopsis↗