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S Lee

Publications and source records attributed to S Lee.

At least 793 records · Page 44Linked to original sources
PubMed1997

Neonatal severity of illness scoring systems: a comparison.

Several different scoring systems have been developed to predict neonatal morbidity and mortality. In this investigation we compared the utility of four severity of illness scoring systems (SISS) as predictors of days on ventilatory (DOV), length of hospital stay (LOS), and mortality in very-low-birth weight (VLBW) premature infants who required mechanical ventilation. The SISS assessed were the Score for Neonatal Acute Physiology (SNAP); the Score for Neonatal Acute Physiology-Perinatal Extension (SNAP + PE); Clinical Risk Index for Babies (CRIB), and the Sinkin Score at 12 hours (SS12). Results revealed significant correlations among the SS12, SNAP, SNAP + PE, CRIB, birth weight (BW), DOV, and LOS. However, none of the systems we assessed offered striking advantage over BW in a VLBW ventilated group.

Evaluation Studies as Topic↗
PubMed1997

Identification of amino acids in the tau 2-region of the mouse glucocorticoid receptor that contribute to hormone binding and transcriptional activation.

The tau 2-region of steroid hormone receptors is a highly conserved region located at the extreme N-terminal end of the hormone-binding domain. A protein fragment encoding tau 2 has been shown to function as an independent transcriptional activation domain; however, because this region is essential for hormone binding, it has been difficult to determine whether the tau 2-region also contributes to the transactivation function of intact steroid receptors. In this study a series of amino acid substitutions were engineered at conserved positions in the tau 2-region of the mouse glucocorticoid receptor (mGR, amino acids 533-562) to map specific amino acid residues that contribute to the hormone-binding function, transcriptional activation, or both. Substitution of alanine or glycine for some amino acids (mutations E546G, P547A, and D555A) reduced or eliminated hormone binding, but the transactivation function of the intact GR and/or the minimum tau 2-fragment was unaffected for each of these mutants. Substitution of alanine for amino acid S561 reduced transactivation activity in the intact GR and the minimum tau 2-fragment but had no effect on hormone binding. The single mutation L550A and the double amino acid substitution L541G+L542G affected both hormone binding and transactivation. The fact that the S561A and L550A substitutions each caused a loss of transactivation activity in the minimum tau 2-fragment and the full-length GR indicated that the tau 2-region does contribute to the overall transactivation function of the full-length GR. Overall, the N-terminal portion of the tau 2-region (mGR 541-547) was primarily involved in hormone binding, whereas the C-terminal portion of the tau 2-region (mGR 548-561) was primarily involved in transactivation.

Amino Acid Sequence↗
PubMed1997

A Ras GAP is essential for cytokinesis and spatial patterning in Dictyostelium.

Using the yeast two-hybrid system, we have identified developmentally regulated Dictyostelium genes whose encoded proteins interact with Ras-GTP but not Ras-GDP. By sequence homology and biochemical function, one of these genes encodes a Ras GAP (DdRasGAP1). Cells carrying a DdRasGAP1 gene disruption (ddrasgap1 null cells) have multiple, very distinct growth and developmental defects as elucidated by examining the phenotypes of ddrasgap1 null strains. First, vegetative ddrasgap1 null cells are very large and highly multinucleate cells when grown in suspension, indicating a severe defect in cytokinesis. When suspension-grown cells are plated in growth medium on plastic where they attach and can move, the cells rapidly become mono- and dinucleate by traction-mediated cell fission and continue to grow vegetatively with a number of nuclei (1-2) per cell, similar to wild-type cells. The multinucleate phenotype, combined with results indicating that constitutive expression of activated Ras does not yield highly multinucleate cells and data on Ras null mutants, suggest that Ras may need to cycle between GTP- and GDP-bound states for proper cytokinesis. After starvation, the large null cells undergo rapid fission when they start to move at the onset of aggregation, producing mononucleate cells that form a normal aggregate. Second, ddrasgap1 null cells also have multiple developmental phenotypes that indicate an essential role of DdRasGAP1 in controlling cell patterning. Multicellular development is normal through the mid-slug stage, after which morphological differentiation is very abnormal and no culminant is formed: no stalk cells and very few spores are detected. lacZ reporter studies show that by the mid-finger stage, much of the normal cell-type patterning is lost, indicating that proper DdRasGAP1 function and possibly normal Ras activity are necessary to maintain spatial organization and for induction of prestalk to stalk and prespore to spore cell differentiation. The inability of ddrasgap1 null cells to initiate terminal differentiation and form stalk cells is consistent with a model in which Ras functions as a mediator of inhibitory signals in cell-type differentiation at this stage. Third, DdRasGAP1 and cAMP dependent protein kinase (PKA) interact to control spatial organization within the organism. Overexpression of the PKA catalytic subunit in ddrasgap1 cells yields terminal structures that are multiply branched but lack spores. This suggests that RasGAP and PKA may mediate common pathways that regulate apical tip differentiation and organizer function, which in turn control spatial organization during multicellular development. It also suggests that DdRasGAP1 either lies downstream from PKA in the prespore to spore pathway or in a parallel pathway that is also essential for spore differentiation. Our results indicate that DdRasGAP1 plays an essential role in controlling multiple, potentially novel pathways regulating growth and differentiation in Dictyostelium and suggest a role for Ras in these processes.

Amino Acid Sequence↗
PubMed1997

Fluorescence imaging in human identity testing.

We have investigated the use of fluorescence detection and the FluorImager S1 System (Molecular Dynamics) for analyzing a comprehensive set of human DNA typing tests. We used an alkaline phosphatase-conjugated YNH24 oligonucleotide probe to the repeat-containing D2S44 locus to detect both alleles in 50 ng of human genomic DNA (0.025 amol) by Southern hybridization using a chemifluorescent substrate. We used a similar approach to quantify human DNA using an enzyme-conjugated oligonucleotide probe to the D17Z1 locus. Both fluorescent nucleic acid gel staining and direct fluorescent labeling methods were tested to detect PCR-based D1S80 and short tandem repeat (STR) multiplex allele profiles. The fluorescent staining method sensitively detected these allelic profiles in both denaturing and non-denaturing acrylamide gels using a simple, 10-min procedure. Fluorescent primers eliminate the doublet band patterns often seen with staining methods, which label both strands of the amplified products. This complicates interpretation of STR typing tests. Only one primer for each locus is labeled, so only one strand of the DNA product is detected. Fluorescein end-labeled primers were used in multiplex PCR to amplify, detect and type STRs.

Benzothiazoles↗
PubMed1997

Pressure-interval relationship characterizes left ventricular irregular beat contractilities and their mean level during atrial fibrillation.

How left ventricular (LV) contractility relates to irregular RR intervals during atrial fibrillation (AF) is still unclear. We investigated the relationship between the LV contractility (Emax) of individual beats and their preceding RR intervals during AF in isovolumic contractions is excised cross-circulated canine hearts, and additionally in ejecting contractions in in situ canine hearts. Atrial high-frequency electrical stimulation induced AF. We recorded a LV electrocardiogram, volume and pressure, and calculated the Emax of every arrhythmic beat. Multiple linear regression analysis between Emax and the six preceding RR intervals of all arrhythmic beats during 1 min AF showed the preceding RR interval (RR1) and the pre-preceding interval (RR2) to be the predominant predictors of Emax. The Emax-RR1/RR2 scattergram was closely fitted by a linear regression line. We found Emax at RR1/RR2 = 1 on the regression line to be virtually identical with both mean Emax during AF and stable Emax obtained during irregular atrial pacing at the same intervals as the mean RR interval during AF. These results newly indicate that the pressure-interval relationship predominantly characterizes LV irregular beat contractilities and their mean level during AF.

Animals↗
PubMed1997

Pancreatic endocrine tumor admixed with a diffuse microcystic adenoma--a case report.

We report a case of pancreatic endocrine tumor admixed with a diffuse microcystic adenoma in a 67-year-old woman with a six months history of melena. Whipple's operation and near-total pancreatectomy were performed under the impression of a pancreatic cancer with duodenal invasion. The pancreas was enlarged and was entirely replaced by sponge-like tiny cysts, which were lined by a single layer of periodic acid Schiff positive cuboidal cells. Also encountered was a gray white solid area at the head portion which extended to the duodenum with an intraluminal polyp formation. The compact area was composed of solid and acinar structures of tumor cells, which showed a positive reaction for chromogranin A and neuron specific enolase, separated by delicate highly vascularized stroma. To the best of our knowledge, this is the first case report published with immunohistochemical studies to deal with a pancreatic endocrine tumor admixed with a diffuse microcystic adenoma.

Adenoma↗
PubMed1997

Extralobar pulmonary sequestration with an associated cyst of mixed bronchogenic and esophageal type--a case report.

We report an unusual case of extralobar pulmonary sequestration (ELS) with an associated cyst of mixed bronchogenic and esophageal type. A 58-year-old woman was incidentally found to have a 6 x 6 x 5 cm sized mass in the right superior mediastinum. The mass consisted of sequestrated pulmonary tissue and an unilocular cyst with a direct communication. The cyst could not be easily classified because it was lined by squamous or respiratory epithelium with two distinct muscle layers and bronchial glands. Bronchial cartilage was present in close proximity to the ELS. This unusual combination of ELS with a foregut cyst might be a part of bronchopulmonary foregut malformation, attributed to a common embryologic pathogenesis.

Bronchogenic Cyst↗
PubMed1997

Monitoring of WT-1 gene expression in peripheral blood of patients with acute leukemia by semiquantitative RT-PCR; possible marker for detection of minimal residual leukemia.

The expression of the WT-1 gene which is found exclusively in human leukemic blasts frequently disappears from bone marrow of leukemia patients in complete remission (CR). Using semiquantitative RT-PCR, we investigated the expression of the WT-1 gene in peripheral bloods (PBs) of 33 patients with acute leukemia (AML 26; ALL 7) and monitored its expression after achievement of CR. None of the 6 normal controls expressed detectable levels of WT-1 transcripts (< 10(-4), background level), whereas 31 (93.9%) of 33 patients expressed variable levels of WT-1 transcripts (range, 10(-4) to 10(1)) at diagnosis. The level of WT-1 expression was not different between AML and ALL. By monitoring WT-1 gene expression in PB of 31 patients during CR, 5 patients relapsed (two from the 18 patients with undetectable levels of WT-1 gene expression and three from the 13 with WT-1 gene expression in low levels). Three of the 5 relapsed patients showed preceding reappearance or rise of WT-1 gene expression. From these results, we reconfirmed that the WT-1 gene is a pan-acute leukemic marker, which can be used to monitor minimal residual leukemia (MRL) after chemotherapy or in patients with CR.

Biomarkers, Tumor↗
PubMed1997

Eight-year experience of malignant lymphoma--survival and prognostic factors.

Several reports have suggested a geographic difference in the histopathologic characteristics and prognosis of malignant lymphoma around the world. We tried to evaluate the clinical and histopathologic characteristics, therapeutic outcomes, and prognostic features of malignant lymphoma, particularly in Korean patients. Three hundred and seventy-six adult patients with the initial histopathologic diagnosis of malignant lymphoma of Yonsei University College of Medicine over an 8-year period were analyzed, retrospectively, with the following results: 1) There were 47 cases of Hodgkin's disease (HD) (12.5%) and 329 of non-Hodgkin's lymphoma (NHL) (87.5%) with a 1:7 ratio. The most common histopathologic subtype of HD was mixed cellularity (44.7%), and that of NHL was intermediate grade (70.8%), especially diffuse large-cell type (44.1%), whereas follicular type was less common. In regard to the incidence of extranodal presentation, it is rare in HD (4.2%), but occurs in 49.8% of patients with NHL. 2) The complete remission (CR) rate was 91.5% in HD and 63.6% in NHL, and the 5-year and 7-year disease-free survival rates were 71.3% and 57.0% in HD; 67.0% and 49.6% in NHL. The 5-year and 8-year overall survival rates were 90.7% and 68.0% in HD; 65.2% and 60.2% in NHL. 3) By multivariate analysis, we found that age, performance status, histopathologic grade, stage, serum lactate dehydrogenase (LDH) and beta 2-microglobulin were the useful prognostic factors in predicting survival in NHL, while no definite prognostic factors were found in HD. Also, in NHL patients less than 60 years old, stage, serum LDH, and histopathologic grade were closely associated with their therapeutic outcomes. In conclusion, the characteristics of malignant lymphoma in our hospital differ from those in Western countries with respect to the clinical, histopathologic and immunophenotypic patterns, but the prognostic factors and overall therapeutic outcomes were quite comparable to those of other reports from Western countries.

Adolescent↗
PubMed1997

Diagnostic criteria of Behçet's disease: problems and suggestions.

There are no specific diagnostic laboratory tests for Behçet's disease. Diagnosis relies on proper history-taking and typical clinical manifestations. To provide more objectivity to the diagnosis, several diagnostic criteria have been introduced including one major set of guidelines by the International Study Group for Behçet's Disease (ISGBD) in 1990 which has made a significant contribution, although some disagreements exist in interpretation. Based on this criteria, recurrent oral ulceration is an obligatory manifestation for the diagnosis of Behçet's disease; however, some data indicates it is not a requirement for the diagnosis. In this article the author critically reviews different accepted diagnostic criteria or classifications of Behçet's disease and gives recommendations for a more thorough diagnosis.

Behcet Syndrome↗
PubMed1997

Dermatologic manifestation of Behçet's disease.

Dermatologic lesions in Behçet's disease are regarded as important manifestation for diagnosis. Various kinds of cutaneous lesions appear in patients with Behçet's disease. They present as erythema nodosum-like lesion, papulopustular eruption, erythema multiforme-like lesion, thrombophlebitis, skin ulcer, Sweet's syndrome-like lesion, bullous necrotizing vasculitis, and pyoderma gangrenosum. The hyperreactivity of the skin to any intracutaneous injection or needle prick, which is known as pathergy, is one clinically-unique feature of the disease.

Behcet Syndrome↗
PubMed1997

Epidemiological and clinical features of Behçet's disease in Korea.

Behçet's disease occurs with a high prevalence in the Far East including Korea. In this report we inspected 1,155 patients with Behçet's disease and collected information concerning the clinical and epidemiologic features of Behçet's disease in Korea. In summary, patients in their 30s were the most common, with the most common age of onset in the 20s; the sex ratio was 0.63:1 with female predominance; according to revised Shimizu's classification, the order of frequency of the different types was incomplete (38.2%), suspected (25.4%), possible (20.3%) and complete (16.1%); oral ulcers were the most frequent major symptom (97.5%) and the most common initial symptom (78.5%); erythema nodosum-like lesion (55.3%) was the most common type of skin lesion; a seasonal aggravation of the disease was observed in 21.3% of patients; and the most common type of childhood onset Behçet's disease was suspected type.

Adolescent↗
PubMed1997

The influence of pregnancy on Behçet's disease.

Behçet's disease is a multisystem disorder that affects mainly young adults. Conflicting reports of the effects of pregnancy on the course of Behçet's disease have been reported. We studied 27 pregnant women with Behçet's disease using questionnaires, clinical examination, and laboratory tests. The condition of 18 patients worsened (66.7%) and 9 patients (33.3%) improved during pregnancy. In the deteriorated group, clinical exacerbation of Behçet's disease occurred most commonly during the first trimester (77.8%). They were primarily of the suspected or mucocutaneous type, while in the improved group, the majority of patients were of the incomplete and complete type, or the arthritic and ocular type. Of interest was the fact that all patients in the improved group showed exacerbations related to menstruation or postpartum, which indicated that progesterone may be the major hormone influencing the course of Behçet's disease.

Adult↗
PubMed1997

Biosynthetic studies on the alpha-glucosidase inhibitor acarbose in Actinoplanes sp.: source of the maltose unit.

To investigate the source of the maltose unit in acarbose, feeding experiments using 3H- or 2H-labeled maltose or maltotriose were carried out with resting cells of Actinoplanes sp. SN223/29. It was found by experiments with [6"-3H]- and [1-3H]maltotriose that a maltose unit from the nonreducing end of maltotriose is incorporated into acarbose more efficiently than from the reducing end. However, experiments with [6"-2H]- and [2-2H]maltotriose showed that maltose from either the reducing end or from the nonreducing end of maltotriose was incorporated into acarbose. The results established that acarbose is formed from maltotriose by two routes; (1) Sixty percent of the acarbose are formed by attachment of maltose, produced by removing a glucose exclusively from the nonreducing end of maltotriose, to the pseudodisaccharide core unit. (2) The other 40% of the acarbose are formed by direct attachment of maltotriose to the core unit followed by loss of the terminal glucose from the reducing end. Furthermore, it was observed that there is no scrambling of label between the two glucose moieties of acarbose, that maltotriose is a comparably efficient precursor of acarbose as is maltose, and that the core unit is enriched up to 50% from the 2H-glucose liberated from the deuterated maltotrioses.

Acarbose↗
PubMed1997

The variable presentation and early recognition of anorexia nervosa in Hong Kong.

One of the western diagnostic criteria for anorexia nervosa is a 'morbid or intense fear of fatness', which is absent in some Chinese anorexic patients in Hong Kong. As a result, patients often visit non-psychiatric doctors and have extensive investigations performed. By the time they are referred to psychiatrists, some may already have reached an advanced stage of illness. In this report of two patients with anorexia nervosa, we attempt to illustrate the variable presentation of anorexic patients in Hong Kong, and to alert health professionals to the early recognition and treatment of this potentially lethal disorder.

Journal Article↗