Biomedical subjects

Na-Hye Myong

Publications and source records attributed to Na-Hye Myong.

8 recordsLinked to original sources

PubMed2006

Electromyographic findings in nucleus pulposus-induced radiculopathy in the rat.

STUDY DESIGN: This study was conducted to investigate the electromyographic changes and their pathophysiologic background in the animal model of nucleus pulposus-induced radiculopathy. OBJECTIVES: To observe the abnormal spontaneous activities in the electromyography (EMG) of rats with nucleus pulposus-induced radiculopathy and assess the role of nitric oxide in their development. SUMMARY OF BACKGROUND DATA: It has been shown that application of nucleus pulposus to nerve roots induces changes consistent with radiculopathy. However, to our knowledge, electromyographic findings and their background have never been studied in this model of radiculopathy. METHODS: Autologous nucleus pulposus was harvested from the tails of Sprague-Dawley rats, and applied to L4 and L5 nerve roots. The rats were tested for mechanical allodynia, motor paresis, and needle EMG, before and after surgery. Specimens of nerve roots were stained histochemically for nitrotyrosine. RESULTS: The rats had mechanical allodynia after surgery, but motor paresis was absent. EMG showed abnormal spontaneous activities after surgery, but only temporarily. Immunoreactivity for nitrotyrosine was detected in the cell bodies and axons of nerve roots. CONCLUSIONS: The data indicate that abnormal spontaneous activities can be observed in electromyographic examination of nucleus pulposus-induced radiculopathy. The development of these activities is considered related to nitric oxide-mediated protein nitration and resultant axonal dysfunction.

Animals↗

PubMed2005

Tissue microarray analysis of Fas and FasL expressions in human non-small cell lung carcinomas; with reference to the p53 and bcl-2 overexpressions.

Lack of surface Fas expression is a main route for apoptotic resistance which is considered an important mechanism of tumorigenesis and tumor progression. Fas and FasL expressions in 110 non-small cell lung carcinomas (NSCLCs) were investigated to evaluate their roles in pulmonary carcinogenesis and to examine the clinicopathologic significance of Fas expression with its relationship with p53 and bcl-2 overexpressions. Immunohistochemical analysis using tissue microarray demonstrated that a large proportion of NSCLC patients (60%) showed lack of membranous Fas expression. The Fas-negative cases revealed the significantly lower survival rate than Fas-positive ones. Also, the loss of Fas receptor expression was found more frequently in advanced stage and higher nodal status. FasL protein was increased in most NSCLCs (89%) compared to normal lungs. p53 and bcl-2 overexpressions showed no association with Fas expression. Conclusively, reduced membranous Fas expression as a mechanism of apoptotic resistance is considered to play an important part of the pulmonary carcinogenesis, which may predict poor survival and have a bad prognostic influence. Increased FasL expression is thought to be a basis for the immune evasion in NSCLCs. The rare bcl-2 overexpression suggests that this anti-apoptotic protein is unlikely to play a role in the apoptotic resistance of NSCLCs.

Apoptosis↗

PubMed2003

Detection of Helicobacter pylori in gastric mucosa of patients with gastroduodenal diseases by PCR-restriction analysis using the RNA polymerase gene (rpoB).

A novel PCR restriction analysis method using the RNA polymerase beta-subunit- coding gene (rpoB) was employed to both detect and identify Helicobacter pylori in biopsy specimens and culture isolates. The rpoB DNAs (458 bp) were specifically amplified by PCR with the Helicobacter-specific primers (HF and HR). Based on the determined rpoB sequences of the culture isolates, an H. pylori-specific restriction site, Tru9I, was found. H. pylori can be identified by observing two discernible DNA fragments (288 and 138 bp) after Tru9I digestion and agarose gel electrophoresis. The rpoB PCR and subsequent restriction analysis (PRA) enabled the specific detection and identification of H. pylori in biopsy specimens from patients with gastroduodenal diseases. The rpoB PRA conferred a compatible or a slightly higher positive rate (53.7%) than did the Campylobacter-like organism (CLO) test (50.4%) and glmM PCR (48.8%), suggesting that it is useful for diagnosing an H. pylori infection without culture in the clinical laboratory.

Bacterial Typing Techniques↗

PubMed2003

First male case of lymphocytic hypophysitis in Korea.

Lymphocytic hypophysitis is a rare inflammatory disorder which is caused by autoimmune destruction of the pituitary gland. Almost all reported cases have been in women and the disease is often associated with pregnancy. We describe here the first male case of lymphocytic hypophysitis in Korea. The patient presented with headache, impotence, decreased libido, and deteriorated vision. Endocrinologic studies showed panhypopituitarism, and pituitary MRI imaging revealed a homogeneously enhanced pituitary mass with a thickened stalk. Treatment with prednisolone and thyroid hormone for five months was ineffective. Transsphenoidal resection of the pituitary mass was performed successfully with normalization of the visual field defect. Histologic examination revealed diffuse lymphocytic infiltration with dense collagenous fibrosis, consistent with lymphocytic hypophysitis. Lymphocytic hypophysitis should be considered in differential diagnosis even in men with hypopituitarism and an enlarged pituitary gland.

Adult↗

PubMed2003

Thyroid transcription factor-1 (TTF-1) expression in human lung carcinomas: its prognostic implication and relationship with wxpressions of p53 and Ki-67 proteins.

This study was aimed to evaluate the prevalence and prognostic implication of thyroid transcription factor-1 (TTF-1) immunoreactivity in 81 human lung carcinomas, including 65 cases of non-small cell lung carcinoma (NSCLC) and 16 cases of small cell lung carcinoma (SCLC); and also to investigate its relationship with the cell proliferation and regulation by immunostaining of Ki-67 and p53 proteins, respectively. The immunohistochemical staining for TTF-1 (clone 8G7G3/1) was performed and several clinicopathologic variables and the follow-up data were obtained. The immunostaining results for TTF-1 were semiquantitatively interpreted as negative and positive. Of NSCLCs, TTF-1 is highly expressed in adenocarcinomas (76%), whereas squamous cell carcinomas revealed no immunoreactivity (0%). SCLCs showed strong TTF-1 expression (88%). In NSCLC, TTF-1 expression was inversely correlated with Ki-67 proliferative activity and independent of p53 overexpression. TTF-1 (+) group tended to show better survival than TTF-1 (-) group in NSCLC. Conclusively, these observations suggest that TTF-1 is a sensitive and specific diagnostic marker for pulmonary adenocarcinomas and SCLCs; that TTF-1 might have a good prognostic implication based on its inverse correlation with Ki-67 proliferative activity and tendency for better survival in NSCLC; that this cell lineage marker may play a role in the molecular pathogenesis of lung cancers at the level of transcription.

Adenocarcinoma↗

PubMed2003

The proteomics approach to find biomarkers in gastric cancer.

Gastric cancer is a very serious disease and is naturally resistant to many anticancer drugs. To reduce the mortality and improve the effectiveness of therapy, many studies have tried to find key biomarkers. Proteomic technologies are providing the tools needed to discover and identify disease-associating biomarkers. The proteomic study of gastric cancer establishes any specific events that lead to cancer, and it provides a direct way to define the true function of genes. Using two dimensional (2-D) electrophoresis of the stomach cancer tissue, we have gained about 1,500 spots in each gel, and 140 protein spots also were identified. Among the identified proteins, there were seven over-expressed proteins in stomach cancer tissue: NSP3, transgelin, prohibitin, heat shock protein (hsp) 27 and variant, protein disulfide isomerase A3, unnamed protein product and glucose regulated protein. There were also seven under-expressed proteins in stomach cancer: Apolipoprotein A-1, p20, nucleoside diphosphate isomerase A, alpha 1 antitrypsin, desmin, serum albumin and serotransferrin.

Adaptor Proteins, Signal Transducing↗

PubMed2002

Mucociliary transport and histologic characteristics of the mucosa of deviated nasal septum.

OBJECTIVE: To investigate differences in mucociliary clearance, histologic characteristics, and surface structure of the bilateral nasal septal mucosa in patients with nasal septal deviation. DESIGN: Mucociliary transport was measured by saccharin clearance time in both nasal cavities of 20 patients with nasal septal deviation. Their septal mucosae were taken during septoplasty, and the ciliary population was studied by scanning electron microscopy. Histologic differences in the lamina propria of septal mucosae were compared under a light microscope. RESULTS: The concave side showed longer saccharin clearance time than the convex side and revealed much more severe loss of cilia. Inflammatory cells more heavily infiltrated the concave side, and seromucinous glands were less densely distributed. CONCLUSION: Concave-side septal mucosae have impaired mucociliary transport, presumably due to ciliary loss, increased inflammation, and decreased density of the glandular acini.

Adult↗

PubMed2002

Primary intimal sarcoma of the aorta: role of transesophageal echocardiography.

Diagnosis of primary tumors of the aorta is difficult. A patient who had a primary intimal sarcoma of the aorta with metastasis presented with obstructive symptoms and computed tomography showed a thrombus-like mass in the aorta. However, transesophageal echocardiography revealed an inhomogeneous and echo-dense mass with an outer membrane, unlike a thrombus, and suggestive of a primary aortic tumor. Pathologic examination of specimens from exploration and autopsy revealed a primary intimal sarcoma.

Adult↗