Biomedical subjects

Jae Yong Lee

Publications and source records attributed to Jae Yong Lee.

11 recordsLinked to original sources

PubMed2006

The role of tonicity responsive enhancer sites in the transcriptional regulation of human hsp70-2 in response to hypertonic stress.

The inducible 70 kDa heat shock proteins (Hsp70) in mice are encoded by two almost identical genes, hsp70.1 and hsp70.3. Studies have found that only hsp70.1 is induced by hypertonic stress while both hsp70.1 and hsp70.3 genes are expressed in response to heat shock stress. It is unclear if the human counterparts, hsp70-2 and hsp70-1, are differentially regulated by heat shock and osmotic stress. This study found that only hsp70-2 was induced by hypertonic stress in human embryonic kidney epithelial cells and fibroblasts, while heat shock stress induced both hsp70-1 and hsp70-2. The human hsp70-2 promoter region contains three TonE (tonicity-responsive enhancer) sites, which were reported to play an important role in the response to hypertonicity. When the reporter plasmids containing different parts of the 5' flanking region of hsp70-2 were transfected into human embryonic kidney epithelial cells or fibroblasts, one TonE site at -135 was found to play a key role in the response to hypertonicity. The inactivation of the TonE site using site-directed mutagenesis led to the complete loss of induction by hypertonicity, which demonstrates the essential role of the TonE site. This suggests that the TonE site and the TonEBP (TonE binding protein) are the major regulators for the cellular response against high osmolarity in human kidney tissue.

5' Flanking Region↗

PubMed2006

Analysis of gene expression profiles of normal human nasal mucosa and nasal polyp tissues by SAGE.

BACKGROUND: A systemic determination of gene expression profiles in nasal polyp compared with normal nasal mucosa would contribute considerably to the investigation of the disease marker in various rhinopathy and general knowledge on the formation of human nasal polyp. OBJECTIVE: The aim of this study was to identify the transcriptome of the normal human nasal mucosa and nasal polyp by the serial analysis of gene expression. METHODS: mRNA was extracted from normal inferior turbinate mucosa and nasal polyp. Short sequences (tags), each one usually corresponding to a distinct transcript, was isolated and concatemerized into long DNA molecules, which were cloned and sequenced. RESULTS: We detected 65,305 tags for normal nasal mucosa and 55,829 tags for nasal polyp, representing 20,629 and 17,636 potential transcripts species, respectively. Of the unique tags encountered more than once, 92% (normal nasal mucosa) and 90% (nasal polyp) matched known genes or expressed sequence tags, whereas the remainder did not match any GenBank sequences. Therefore, 504 and 539 novel transcripts were identified in normal nasal mucosa and nasal polyp, respectively. Although the expression levels of most transcripts in both libraries were similar, 114 transcripts were differentially expressed at a statistically significant level (P < .05)-that is, 65 and 49 transcripts among them were expressed at a higher level in normal nasal mucosa and nasal polyp, respectively. CONCLUSION: This information should be very useful for basic knowledge as well as for future studies on pathophysiological conditions of human nasal mucosa, providing some clues to evaluate the altered factors in a variety of rhinopathies. CLINICAL IMPLICATIONS: The results of this study might contribute to general knowledge on the formation of human nasal polyp.

Adult↗

PubMed2006

Comparative study on the long-term effectiveness between coblation- and microdebrider-assisted partial turbinoplasty.

OBJECTIVES: Various surgical methods have been tried to relieve the symptoms of nasal obstruction in patients with inferior turbinate hypertrophy. Recently, coblation that uses the radiofrequency and microdebrider is being increasingly used in turbinate surgery. The aim of this study was to compare the long-term postoperative outcome between the coblation- and microdebrider-assisted partial turbinoplasty. METHODS: We selected 60 patients for this prospective study who had nasal obstruction and hypertrophied turbinate mucosa that was refractory to medical treatment. Thirty patients were treated with coblation (group 1) and 30 patients were treated with microdebrider (group 2). Postoperative changes in degree of nasal obstruction were evaluated prospectively at 3, 6, and 12 months after the procedure. A cross-sectional area of second notch and volume of nasal cavity were compared at 12 months after operation. Operation time, duration of crust formation, postnasal drip, and postoperative bleeding were also compared. RESULTS: Nasal obstruction was improved significantly in both groups at 3, 6, and 12 months after the procedure. However, when compared between two groups, symptom improvement was statistically significant in group 2 at 12 months after surgery. Acoustic rhinometry performed at 12 months demonstrated a significant increase of cross-sectional area of second notch and volume of nasal cavity in group 2 in comparison with group 1. There were no significant differences in degree of postnasal drip, operation time, or duration of crust formation between the two groups. CONCLUSION: This study suggests that microdebrider-assisted partial turbinoplasty is more effective and satisfactory in long-term relief of nasal obstruction and reduction in mucosal volume of anterior head of inferior turbinate.

Adolescent↗

PubMed2006

Usefulness of autologous cartilage and fibrin glue for the prevention of septal perforation during septal surgery: a preliminary report.

OBJECTIVES: Septal surgery is one of the most common causes of nasal septal perforation. In cases in which a septal mucosal defect at the corresponding area has occurred, autologous cartilage is usually inserted between the injured mucosal flaps. In addition, we applied fibrin glue to the margins of injured mucosal surface to fix the inserted cartilage and to promote mucosal regeneration. The aim of this study was to evaluate the efficacy of this method in the prevention of nasal septal perforation. STUDY DESIGN: Retrospective analysis of medical records. METHODS: A total of 463 septal surgeries were performed between March 2003 and August 2005. Septal mucosal defect at the corresponding area occurred in 34 patients. In group 1 (23 patients), septal or auricular cartilage was inserted between the injured mucosal flaps. In group 2 (11 patients), septal or auricular cartilage was inserted, and fibrin glue was applied on the mucosal margins of cartilage insertion site. We compared the perforation rate between the two groups. RESULTS: In group 1, nasal septal perforation occurred 8 of 23 (34.8%) patients, and in group 2, 1 of 11 (9.1%) patients experienced perforation. Although the occurrence rate of perforation was significantly lower in group 2, statistical significance between the two groups could not be established because of the small number of patients who experienced septal perforation. CONCLUSION: The application of fibrin glue at the bilaterally injured mucosal surface after cartilage insertion is thought to be very useful as a preventive measure of nasal septal perforation. We report these results as preliminary data for further study to determine the usefulness of fibrin glue in the prevention of nasal septal perforation.

Adolescent↗

PubMed2006

Is lack of placement of drains after thyroidectomy with central neck dissection safe? A prospective, randomized study.

OBJECTIVE: Selective use of drains after thyroidectomy has been suggested in the literature. Although the safety of thyroidectomy without drains has been reviewed, there is little specific data available to identify the safety of thyroidectomy combined with central neck dissection (CND) without drains. This study aims to determine the feasibility and safety of thyroidectomy without drains, especially in cases of combined CND. STUDY DESIGN: Prospective, randomized study. MATERIALS AND METHODS: One hundred ninety-eight consecutive thyroidectomized patients were enrolled in this study. Drain group (n = 101) consisted of 41 hemithyroidectomies (HT), 28 total thyroidectomies (TT), and 32 total TT with CND. No-drain group (n = 97) consisted of 42 HT, 18 TT, and 37 TT with CND. The following variables were examined: perioperative complications (hemorrhage, hematoma, seroma), intraoperative bleeding, operation time, volume of resected thyroid gland, time of hospital discharge after operation, duration of drain placement, and total amount of drainage (drain group). RESULTS: There were no significant differences in age, sex, volume of resected thyroid gland, types of operation, operation time, and histopathlologic diagnosis between two groups. In the drain group, overall perioperative complications occurred in seven (7/101, 6.9%) patients. In the no-drain group, overall perioperative complications occurred in nine (10/97, 10.3%) patients. There was no significant difference in overall perioperative complications between the drain and no-drain groups, even in cases of performing CND. Time of hospital discharge after operation was significantly shorter in the no-drain group than the drain group (P < .05). CONCLUSIONS: We conclude that thyroidectomy without drains is safe and effective even in combination with CND and appears to confer several advantages over the routine drainage method. In addition, we achieved significant reduction of hospital stay, which led to a reduction in costs for the patients.

Adolescent↗

PubMed2005

Downstream components of RhoA required for signal pathway of superoxide formation during phagocytosis of serum opsonized zymosans in macrophages.

Rac1 and Rac2 are essential for the control of oxidative burst catalyzed by NADPH oxidase. It was also documented that Rho is associated with the superoxide burst reaction during phagocytosis of serum- (SOZ) and IgG-opsonized zymosan particles (IOZ). In this study, we attempted to reveal the signal pathway components in the superoxide formation regulated by Rho GTPase. Tat-C3 blocked superoxide production, suggesting that RhoA is essentially involved in superoxide formation during phagocytosis of SOZ. Conversely SOZ activated both RhoA and Rac1/2. Inhibition of RhoA-activated kinase (ROCK), an important downstream effector of RhoA, by Y27632 and myosin light chain kinase (MLCK) by ML-7 abrogated superoxide production by SOZ. Extracellular signaling-regulated kinase (ERK)1/2 and p38 mitogen-activated protein kinase (MAPK) were activated during phagocytosis of SOZ, and Tat-C3 and SB203580 reduced ERK1/2 and p38 MAPK activation, suggesting that RhoA and p38 MAPK may be upstream regulators of ERK1/2. Inhibition of ERK1/2, p38 MAPK, phosphatidyl inositol 3-kinase did not block translocation of RhoA to membranes, suggesting that RhoA is upstream to these kinases. Inhibition of RhoA by Tat-C3 blocked phosphorylation of p47(PHOX). Taken together, RhoA, ROCK, p38MAPK, ERK1/2, and p47(PHOX) may be subsequently activated, leading to activation of NADPH oxidase to produce superoxide.

Animals↗

PubMed2005

Expression and distribution of ion transport mRNAs in human nasal mucosa and nasal polyps.

CONCLUSIONS: Our results indicate that the electrogenic kidney Na(+)/HCO(3)(-) cotransporter (kNBC), KCl cotransporter (KCC1 and -4) and Ca(2+)-activated Cl(-) channel (CaCC1, -2, -3) mRNAs are expressed in normal nasal mucosa and nasal polyp, suggesting that altered expression of all CaCC mRNAs in nasal polyp may cause impaired electrolyte and water transport across the epithelial cells. OBJECTIVE: Electrolyte transport by nasal epithelia has been suggested to be important for controlling the quantity and composition of the nasal fluid and may play an important role in the development of nasal polyps. Transepithelial transport of ions and water in various fluid-transporting epithelia is strictly dependent on the localization of specific membrane proteins in the polarized epithelial cells. In this study we investigated the expression and distribution of mRNA transcripts for kNBC, pancreatic NBC, KCC1, -2, -3, -4 and CaCC1, -2, -3 gene families in human nasal mucosa and nasal polyp. MATERIAL AND METHODS: The expression and localization of these gene families were investigated in inferior turbinate tissues and nasal polyp using reverse transcriptase polymerase chain reaction (RT-PCR), semiquantitative RT-PCR and in situ hybridization. RESULTS: mRNAs for kNBC, KCC1 and -4 and all the CaCC families (CaCC1, -2 and -3) are expressed in human turbinate mucosa and nasal polyp. The expression levels of kNBC and KCC1 and -4 mRNAs did not differ between nasal mucosa and nasal polyp. However, the expression levels of all the CaCC genes were significantly decreased in nasal polyp. In situ hybridization revealed that the expression of these genes was mainly localized in the epithelial layer and submucosal glands of inferior turbinate mucosa and in the epithelial layer of nasal polyp.

Adult↗

PubMed2004

Intracellular delivery of p53 fused to the basic domain of HIV-1 Tat.

p53 is a potent tumor suppressor inactivated in many cancers. In this study, the membrane permeability of the HIV-1 Tat basic domain was exploited to introduce functional p53 into cancer cells. We expressed and purified a p53 fusion protein with the HIV-1 Tat basic domain at its N terminus (Tat-p53), and examined its transduction profile and biological activity in cancer cells. Tat-p53 was efficiently delivered to both the cytoplasm and nucleus of cells, and was transcriptionally active, as judged by the level of p21/WAF1 protein and of p21 promoter activity. Transduction of cells with Tat-p53 resulted in apoptotic cell death in both p53 positive and negative human tumor cell lines. These results suggest that Tat-p53 could be useful in cancer therapy.

Apoptosis↗

PubMed2004

Exposure to genistein does not adversely affect the reproductive system in adult male mice adapted to a soy-based commercial diet.

Genistein, a soybean-originated isoflavone, is widely consumed by humans for putative beneficial health effects but its estrogenic activity may affect adversely the development of male reproductive system. Five-week-old ICR mice were purchased and fed with a soybean-based Purina Chow diet until 6 months of age. The animals were exposed by gavage to genistein (2.5 mg/kg/day) or 17beta-estradiol (7.5 microg/kg/day) for five weeks. Corn oil was used for the negative control. The animals were fed the casein-based AIN-76A diet throughout the experimental periods. There were no significant differences in body and organ weights of mice among experimental groups. No significant differences in sperm counts and sperm motile characteristics were found between the control and the genistein groups. Treatment of 17beta-estradiol caused a significant decrease in epididymal sperm counts compared to the control (p<0.05). The level of phospholipid hydroxide glutathione peroxidase in the epididymis of mice exposed to genistein was significantly higher than that of the control mice (p<0.05). 17beta-estradiol treatment caused a reduction of germ cells in the testis and hyperplasia of mucosal fold region in the prostate of mice. Genistein treatment did not cause any lesion in the testis, epididymis, and prostate. These results suggest that dietary uptake of genistein at adult stage of life may not affect male reproductive system and functions.

Animals↗

PubMed2003

Dexamethasone-induced differentiation of pancreatic AR42J cell involves p21(waf1/cip1) and MAP kinase pathway.

Dexamethasone converts pluripotent pancreatic AR42J cells into exocrine cells expressing digestive enzymes. In order to address molecular mechanism of this differentiation, we have investigated the role of mitogen-activated protein (MAP) kinase pathway and gene expressions of p21(waf1/cip1) and nuclear oncogenes (c-fos and c-myc) during AR42J cell differentiation. Dexamethasone markedly increased the intracellular and secreted amylase contents as well as its mRNA level. However, cell growth and DNA content were significantly decreased. With these phenotypic changes, AR42J cells induced transient mRNA expression of p21(waf1/cip1) gene, which reached maximal level by 6 h and then declined gradually toward basal state. In contrast to p21(waf1/cip1), c-fos gene expression was transiently inhibited by 6 h and then recovered to basal level by 24 h. Increased c-myc expression detected after 3 h, peaked by 12 h, and remained elevated during the rest of observation. Dexamethasone inhibited epidermal growth factor-induced phosphorylation of extracellular signal regulated kinase. Inhibition of MAP kinase pathway by PD98059 resulted in further elevation of the dexamethasone-induced amylase mRNA and p21(waf1/cip1) gene expression. These results suggest that p21(waf1/cip1) and nuclear oncogenes are involved in dexamethasone-induced differentiation and inhibition of MAP kinase pathway accelerates the conversion of undifferentiated AR42J cells into amylase-secreting exocrine cells.

Amylases↗

PubMed2002

Spatiospectral transmission of a plane-mirror Fabry-Perot interferometer with nonuniform finite-size diffraction beam illuminations.

The transmission of a plane-mirror Fabry-Perot (PFP) interferometer is theoretically modeled and investigated by treating the spatial and spectral features in a unified manner. A spatiospectral transfer function is formulated and utilized to describe the beam propagation and the multiple-beam interference occurring in an ideal one-dimensional strip PFP interferometer with no diffraction loss. The spatial-frequency filtration of a finite-size beam input not only determines the transmitted spatial beam profile but also plays a crucial role in affecting the overall spectral transmittance. The inherent deviations of the spectral transmittance from what we know as the standard Airy's formula are revealed in diverse aspects, including the less-than-unity peak transmittance, the displacement of a resonance peak frequency, and the asymmetric detuning profile. Our theoretical analysis extends to the misaligned PFP interferometers, such as the cases in which non-normal-incidence beams or wedge-aligned mirrors are used that could severely degrade the effective interferometer finesse.

Journal Article↗