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Biomedical subjects

M Lee

Publications and source records attributed to M Lee.

At least 397 records · Page 22Linked to original sources
PubMed1998

(Re)constructing relationships with grandparents: a turning point analysis of granddaughters' relational development with maternal grandmothers.

This study explores how granddaughters account for the development of their relationships with their maternal grandmothers. The retrospective interviewing technique was used to elicit turning points in their relational histories. Analysis of the turning point content revealed several different types of turning points that reflected both normative and idiosyncratic events. Increases in relational closeness resulted from decreases in geographic separation, engaging in shared activities, deaths or serious illnesses in the family, and family disruptions. Decreases in closeness were associated with negative experiences with the grandmother, increases in geographic separation, and the transition to college. Granddaughters reported that turning points related to death or serious illness and participation in shared activities were the most significant ones in their relationships with maternal grandmothers.

Adolescent↗
PubMed1998

Heterogeneity of IgE response to TDI-HSA conjugates by ELISA in toluene diisocyanate (TDI) -induced occupational asthma (OA) patients.

Toluene diisocyanate (TDI), a low molecular weight reactive chemical, is known to be a main cause of occupational asthma (OA) in Korea. Although it is thought that inhaled TDI may act as a hapten, the precise mechanisms of TDI-induced OA are unknown. In this study, TDI-human serum albumin (HSA) conjugates (5, 10, 20 and 30 min) were prepared in the range of 1.5 to 5.0 TDI mole/HSA mole. Specific binding of serum IgE to TDI-HSA (30 min) was observed using IgE ELISA as well as ELISA inhibition assay. Around 40% of TDI-induced OA patients were positive for serum specific IgE by ELISA. Degrees of serum IgE binding were different depending on which TDI-HSA conjugate was used as an antigen. Moreover, binding patterns were different depending on the individuals. Interestingly, higher binding of IgE to TDI-HSA (5 min) than to TDI-HSA (30 min) which was more highly substituted was observed in some patients. Probably new antigenic epitopes on carrier proteins were targets of the specific IgE. The results of this study indicated that IgE responses to TDI-HSA conjugates were heterogeneous in TDI-induced OA patients and self-proteins modified by reactive chemicals can become a major target antigen of IgE in certain cases.

Antibody Specificity↗
PubMed1998

Cytokine secretion patterns of T cells responding to haptenized-human serum albumin in toluene diisocyanate (TDI)-induced asthma patients.

Our understanding immune response mechanisms to chemical allergens has been limited. It was partly due to the nature of antigens, recognized by T cells, not being well characterized. In the present study, we examined a hypothesis that a reactive chemical allergen, toluene diisocyanate (TDI), react with autologous proteins, thereby inducing T cell responses to the modified self protein in vivo. TDI-human serum albumin (HSA) conjugates were prepared and the presence of antigenic epitopes on the TDI-HSA conjugate was confirmed by IgE ELISA. We examined proliferative and cytokine production responses in TDI-induced asthma patients using the TDI-HSA conjugate as an antigen. Although proliferative responses of peripheral blood mononuclear cells (PBMCs) were not detected, production of IFN-gamma was observed in both PBMC and T cell lines obtained from some newly-diagnosed patients by ELISA. Mitogen-inducible IL-4 production was also detected in some T cell lines. Results of this study may have two implications. One is that presentation of haptenized-self protein to the immune system may induce activation of T cells. The other is that T cells responding to this modified self protein may play a role in the pathogenesis of the chemical allergen-induced asthma by producing cytokines such as IFN-gamma and possibly IL-4.

Allergens↗
PubMed1998

The effect of heterogeneous hyperimmune IgG antibody on prophylaxis and treatment of Pneumocystis carinii infection in rats.

Immunotherapy has been used in support of trimethoprim-sulfamethoxazole treatment for Pneumocystis carinii pneumonia. The present study investigated the therapeutic or preventive effects of heterogeneous hyperimmune IgG antibody (HIA) in experimental rats. Their immunity was suppressed by steroid injection, and they were also injected peritoneally with HIA which reacted with 40-55, 92, 116, and 200 kDa bands of the crude antigen. All rats were infected by P. carinii and the cystic forms on lung impression smears were counted. The count was 20.5-76.5 (mean 52.5 + 19.3) in those which received steroid only, but decreased to 6.0-21.0 (mean 13.5 + 10.6) in those of group 3 which received HIA for the same duration. In other groups, the mean count ranged from 29.9 + 32.9 to 54.1 + 47.7, and in those which received 13.7 mg HIA the reduction effect was greater than in those which received 6.8 mg or 20.5 mg HIA. The present finding confirmed that in rats during the early stage of infection, the heterogeneous HIA to MSG antigen bands had a partial effect on P. carinii pneumonia, both prophylactically and therapeutically.

Animals↗
PubMed1998

Control of clonorchiasis by repeated praziquantel treatment and low diagnostic efficacy of sonography.

In Korea, Clonorchis sinensis infection is still highly prevalent because case detection in the field is difficult and the detected cases used to be incompletely cured due to treatment failure. The present study tried to control clonorchiasis in an endemic village by repeated treatments with praziquantel every 6 months and to evaluate sonography as a diagnostic measure. By stool examinations, the egg positive rate in the endemic village was 22.7%, but it decreased to 19.6% at 6 months, 15.1% at 12 months. 12.2% at 18 months, 6.3% at 24 months, 11.4% at 30 months, and 6.3% at 42 months after the beginning of repeated praziquantel administration. The sonography showed 61 (49.6%) positive cases of 123 screened residents: among egg-positives the sonography positive rate was 52.2% and among egg-negatives it was still 49%. The rate among cured cases was 64.3% after 6 months, 50.0% after 12 months, 50.0% after 18 months, and 66.7% after 24 months. In a non-endemic village, 64 residents were found egg-negative by fecal examination, but 20 (31.3%) of them were positive by sonography. The present findings indicate that control of clonorchiasis in an endemic village by repeated praziquantel treatment for 42 months is still insufficient and sonography is of little value for diagnosis of clonorchiasis.

Animals↗
PubMed1998

Clinical and electrophysiological characteristics in Korean patients with WPW syndrome.

This study was designed to investigate the clinical and electrophysiologic characteristics of WPW syndromes in Korea. A total of 400 symptomatic WPW syndrome patients were consecutively recruited. The most common documented symptomatic tachyarrhythmia was orthodromic atrioventricar reentrant tachycardia (75.3%), followed by atrial fibrillation (31.3%), and antidromic atrioventricular reentrant tachycardia (6.2%). There was a higher incidence of multiple bypass tract in patients with antidromic tachycardia than in those with orthodromic tachycardia (30.4 vs 4.3%, P < 0.001). The inducibility of tachyarrhythmia with electrophysiologic study in this study population was 95.8%. The most frequent location of the accessory pathway was the left free wall (48.0%), followed by the right free wall (29.1%), posterior septum (17.5%) and anterior septum (3.5%). These results indicated that 1) clinical and electrophysiological characteristics of Korean patients with WPW syndrome were similar to those of western countries and 2) the electrophysiologic study was important in the evaluation of patients with WPW syndrome.

Adolescent↗
PubMed1998

Establishing guidelines for the role of minor salivary gland biopsy in clinical practice for Sjögren's syndrome.

OBJECTIVE: To evaluate the predictive value of clinical variables for the finding of a positive minor salivary gland biopsy (focus score > or = 2) in patients investigated for Sjögren's syndrome (SS). METHODS: One hundred twenty-one patients with sicca symptoms were referred to a multidisciplinary SS clinic in a tertiary hospital. Each patient was evaluated on protocol and labial salivary gland (LSG) biopsy was obtained. Using the San Diego criteria as a model, patient data were subjected to a cross sectional analysis on an algorithm to determine when the LSG biopsy would be most useful for determining the diagnosis of SS in clinical practice. RESULTS: Eighty-four patients had sufficient data to be included in the study. Forty patients had LSG biopsy with focus score < 2 and 44 had focus score > or = 2. Twenty-three patients had objective evidence of sicca and positive serology according to criteria standards. Eighteen of these had a positive biopsy (78%). The remaining 5 patients had many extraglandular features suggestive of SS, and the biopsies appeared to add little practical information. Patients with incomplete criteria for sicca could be diagnosed as possible SS (3 of 4 criteria) with a positive biopsy in 14 of 18 cases. The finding of anti-Ro or anti-La positivity in patients with incomplete criteria for sicca predicted a positive LSG biopsy in 85.7% of such cases. Patients with incomplete sicca and negative anti-Ro and anti-La had a negative LSG biopsy in 82% of cases. CONCLUSION: The LSG biopsy is most necessary in patients who have partial San Diego criteria for sicca and positive anti-Ro or anti-La antibody. Where SS is not reasonably suspected, or where the diagnosis is clinically obvious, the LSG biopsy adds little useful clinical information.

Antibodies, Antinuclear↗
PubMed1998

Gene array and expression of mouse retina guanylate cyclase activating proteins 1 and 2.

PURPOSE: To identify gene arrangement, chromosomal localization, and expression pattern of mouse guanylate cyclase activating proteins GCAP1 and GCAP2, retina-specific Ca2+-binding proteins, and photoreceptor guanylate cyclase activators. METHODS: The GCAP1 and GCAP2 genes were cloned from genomic libraries and sequenced. The chromosomal localization of the GCAP array was determined using fluorescent in situ hybridization. The expression of GCAP1 and GCAP2 in mouse retinal tissue was determined by immunocytochemistry. RESULTS: In this study, the mouse GCAP1 and GCAP2 gene array, its chromosomal localization, RNA transcripts, and immunolocalization of the gene products were fully characterized. The GCAP tail-to-tail array is located at the D band of chromosome 17. Each gene is transcribed into a single transcript of 0.8 kb (GCAP1) and 2 kb (GCAP2). Immunocytochemistry showed that both GCAP genes are expressed in retinal photoreceptor cells, but GCAP2 was nearly undetectable in cones. GCAP2 was also found in amacrine and ganglion cells of the inner retina. Light-adapted and dark-adapted retinas showed no significant difference in the distribution of the most intense GCAP2 staining within the outer segment and outer plexiform layers. CONCLUSIONS: Identical GCAP gene structures and the existence of the tail-to-tail gene array in mouse and human suggest an ancient gene duplication-inversion event preceding mammalian diversification. Identification of both GCAPs in synaptic regions, and of GCAP2 in the inner retina suggest roles of these Ca-binding proteins in addition to regulation of phototransduction.

Adaptation, Ocular↗
PubMed1998

[p53 expression and response to hepatic intraarterial infusion chemotherapy in patients with colorectal cancer metastasis to liver].

We have reported that hepatic artery infusion (HAI) chemotherapy with 5-fluorouracil for unresectable colorectal liver metastasis may lead to improved overall survival for some patients compared with controls. The aim of this work is to determine whether p53 nuclear protein expression examined by immunohistochemical technique could predict the outcome of patients treated with HAI chemotherapy. No significant difference was found in the response rate (p > .99, Fisher's exact method.) and median survival time (12 months in patients with p53-positive tumors and 11 months with negative tumors). Our results indicate that HAI chemotherapy is an effective treatment for liver metastasis regardless of p53 nuclear protein expression.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1997

Subregional localization of 21 chromosome 7-specific expressed sequence tags (ESTs) by FISH using newly identified YACs and P1s.

Twenty-one putative chromosome 7-derived expressed sequence tags (ESTs) identified 33 yeast artificial chromosomes (YACs) or P1 clones, which were then used as reagents for physical mapping. FISH mapping established that the ESTs contained within these clones were distributed throughout chromosome 7, with all major cytogenetic bands represented, except 7p13-p15, 7p11, 7q31.2, and 7q35. Each EST sequence identified at least one other sequence in publicly available databases (using search tools such as BLASTN, basic local alignment search tool), and many of the ESTs identified cDNAs and several genomic DNA sequences. However, 7 ESTs did not identify highly significant matches (P < 1 x 10(-5)). Only one (EST01924-D7S2281E) failed to identify any other EST from the dbEST homology searches. BLAST analysis identified at least five genes from EST sequence comparisons: protein tyrosine phosphatase zeta (PTPRZ, also known as RPTPZ) (EST02092), which we had mapped to 7q31.3, in agreement with previous studies; cAMP-dependent protein kinase regulatory subunit bI (EST01644); rat integral membrane glycoprotein (EST00085); human IFNAR gene for interferon alpha/beta receptor (EST00817); and rat 14-3.3 protein gamma subtype (putative protein kinase C regulatory protein) (EST00762). These ESTs will help to develop the map of chromosome 7, which integrates physical, transcriptional, and cytogenetic data, as well as to provide candidate disease genes for chromosome 7-specific disorders.

Animals↗
PubMed1997

Structure of the mouse leukaemia inhibitory factor receptor gene: regulated expression of mRNA encoding a soluble receptor isoform from an alternative 5' untranslated region.

The low-affinity leukaemia inhibitory factor receptor (LIF-R) is a component of cell-surface receptor complexes for the multifunctional cytokines leukaemia inhibitory factor, ciliary neurotrophic factor, oncostatin M and cardiotrophin-1. Both soluble and transmembrane forms of the protein have been described and several LIF-R mRNAs have been reported previously. In order to determine the coding potential of LIF-R mRNAs we have isolated and characterized the mouse LIF-R gene. mRNA encoding soluble LIF-R (sLIF-R) is formed by inclusion of an exon in which polyadenylation signals are provided by a B2 repeat. This exon is located centrally within the LIF-R gene but is excluded from the transmembrane LIF-R mRNA by alternative splicing. The transmembrane receptor is encoded by 19 exons distributed over 38 kb. Two distinct 5' non-coding exons have been identified, indicating the existence of alternative promoters. One of these is G/C rich and possesses a consensus initiator sequence as well as potential Sp1 binding sites. Expression of exon 1 from this promoter occurs in a wide variety of tissues, whereas expression of the alternative 5' untranslated region (exon 1a) is normally restricted to liver, the principal source of sLIF-R. During pregnancy expression of exon 1a becomes detectable also in the uterus. Expression of exon 1a increases dramatically during gestation and is accompanied by a similar quantitative rise in expression of sLIF-R mRNA. These findings establish that expression of LIF-R is under complex transcriptional control and indicate that regulated expression of the soluble cytokine receptor isoform may be due principally to an increase in the activity of a dedicated promoter.

Animals↗
PubMed1997

Long terminal repeat and nef gene variants of human immunodeficiency virus type 1 in perinatally infected long-term survivors and rapid progressors.

HIV-1 sequences from perinatally infected children were analyzed in the long terminal repeat (LTR) region and nef in order to investigate associations of viral variation and disease progression. Four long-term survivors who reached 10 years of age or older, and four rapid progressors who survived less than 2 years, participated in this study. LTR sequences of multiple independent viral variants from each individual were compared. No sequence pattern within the LTR consistently distinguished long-term survivors from rapid progressors or vice versa. Deletions and insertions within transcription factor binding sites of the LTR and nef ranging from 8 to 341 bp were found in viral variants from the eldest long-term survivor (LTS047). These deletions and duplications may be associated with the survival of LTS047 via an unknown mechanism. Among all children in this study, the sites in the untranslated region (NF-kappaB, SP1, and TATA box) were more conserved than the sites in the nef/LTR overlap region (NFAT, purine-rich region, USF, TCF1alpha), reflecting the importance of the sites in the untranslated region for viral replication. A mutation in the E box motif within the USF site among the sequences from a long-term survivor (LTS113) is predicted to disrupt protein binding and may be associated with slow disease progression. Mutations of the SP1-III site in a rapid progressor (RP056) indicate that this site is not necessary for rapid disease progression.

Amino Acid Sequence↗
PubMed1997

Posteroanterior stiffness in the lumbosacral spine. The correlation between adjacent vertebral levels.

STUDY DESIGN: A descriptive design of posteroanterior stiffness in the lumbosacral spine. OBJECTIVES: To measure posteroanterior stiffness between L1 and S1 to establish the pattern of stiffness in individuals with no history of low back pain. SUMMARY OF BACKGROUND DATA: In clinical examination for low back pain, manual assessment of abnormal stiffness is used to determine the site of the pain-producing lesion. However, there is little objective evidence of the variation in stiffness between levels in normal spines or of the factors that determine posteroanterior stiffness. METHOD: Posteroanterior stiffness was measured with a specially developed measuring device at each of the six vertebral levels between L1 and S1. Force-displacement relations were computed for each vertebral level. The gradient of the linear part of the force-displacement relation was used as a coefficient of stiffness, and the amount of displacement between 5 N and 30 N of applied force (D5-30) was used as a measure of the length of the toe region. RESULTS: Overall there was a significant linear trend of increasing stiffness from L1 to S1. Ninety percent of the difference scores for adjacent level comparisons were less than 3.6 N/mm. There was considerable variation in the patterns of stiffness found in different individuals. The stiffness coefficient and D5-30 correlated significantly with skinfold thickness measurements and body mass index. CONCLUSION: A linear trend of increasing stiffness was found between L1 and S1, but this pattern was influenced by variables related to body type (adiposity).

Adult↗
PubMed1997

Long-term potentiation trains induce mossy fiber sprouting.

It has been shown that both amygdaloid and hippocampal kindling induce sprouting of the mossy fibers in the dentate gyrus. In this study, we investigated whether non-epileptogenic stimulation could also induce mossy fiber sprouting. Long-term potentiation (LTP) was induced in the dentate gyrus by the application of brief, high frequency trains to the perforant path. The potentiating stimulation was applied each day for 10 days, and the tissue was prepared for Timm labelling 7 days later. Sprouting was significantly increased in the LTP group compared to the implanted control rats. These results suggest that mossy fiber sprouting is not damage-induced and is dependent on neuronal activation.

Animals↗