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Hyun Jun Kim

Publications and source records attributed to Hyun Jun Kim.

16 recordsLinked to original sources
PubMed2006

Immunohistochemical study of the distribution of sodium-dependent vitamin C transporters in adult rat brain.

Sodium-dependent vitamin C transporters (SVCTs) is known to transport the reduced form of ascorbic acid into the cell, whereas the oxidized form of vitamin C (VC) is moved through a facilitative sugar transporter, such as glucose transporter (GLUT). With regard to the distribution of SVCT1 and -2 within the various organs, they were reported to be expressed in different types of cells. Especially in the central nervous system, only SVCT2 mRNA was expressed mainly in neurons and some types of neuroglial cells. However, data on the expression of SVCT proteins in the brain are scant. Therefore, we tried to develop comprehensive data on the distribution of SVCT proteins in adult rat brain by using immunohistochemical techniques for the first time. In our study, SVCT2 immunoreactivities (IRs) were intensely localized in the neurons of cerebral cortex, hippocampus, and Purkinje cells of cerebellum, and much weaker SVCT2 IRs were found in the other brain regions. Judging from double-immunohistochemical data, most of the cells expressing SVCT2 IRs were likely to be neurons or microglia, even though the cells in choroids plexus or ependymal cells around the ventricles also exhibited SVCT2 IRs. Complete mapping of the distribution of SVCT2 IRs was available by using a semiquantitative method. The subcellular localization of SVCT proteins is necessary for understanding the exact role of the protein, so the current overall mapping of SVCT IRs in the rat brain could be the basis for further studies on related subjects.

Animals↗
PubMed2006

Bacteriological findings and antimicrobial susceptibility in chronic sinusitis with nasal polyp.

CONCLUSIONS: We recommend amoxacillin/clavulanate, cephalosporins and macrolides rather than penicillin as the first-line drug in chronic sinusitis with nasal polyps. In cases where there is no improvement of symptoms, cultures should be taken from the middle meatus, followed by appropriate selection of second-line antibiotics according to the sensitivity test results. OBJECTIVE: To investigate the causative bacteria and the antimicrobial susceptibility in patients with chronic sinusitis and nasal polyps in Korea. MATERIALS AND METHODS: The bacteriology and antimicrobial susceptibility of maxillary sinus aspirates from 81 patients were evaluated. RESULTS: Aerobes were isolated from 58.0% of the cultures from the middle meatus and from 48.1% of those from the maxillary sinus. Staphylococcus aureus, Haemophilus influenzae, and Streptococcus pneumoniae were the most prevalent aerobic pathogens. Anaerobes were isolated from 8.6% of the cultures from the middle meatus and from 18.5% of the cultures from the maxillary sinus. The predominant anaerobic organisms were Prevotella and Peptostreptococcus in adults but none of them were cultured in children. A high rate of concordance of the middle meatus and maxillary sinus was noted. Monomicrobial infection was most commonly observed. Ampicillin-resistant H. influenzae isolates were cultured in 46% of the cases. Penicillin resistance rates were 93% for Staph. aureus; 25% of Strep. pneumoniae were intermediate and 25% were resistant.

Adolescent↗
PubMed2006

The relationship between anatomic variations of paranasal sinuses and chronic sinusitis in children.

CONCLUSIONS: Anatomical variations in the nose and paranasal sinuses are common in children. Due to the absence of a definitive relationship between anatomical variations and sinus disease, local, systemic or environmental factors appear to be more significant in pediatric sinusitis than the anatomic variations. OBJECTIVE: Chronic sinusitis is increasing in the pediatric population. Following the initial reports of functional endoscopic sinus surgery (FESS) for children, the majority of patients undergoing this procedure have experienced improved quality of life. Thus, we need to know the precise anatomy and anatomical variations of the nose, as well as the relationship between such anatomy and chronic sinusitis. PATIENTS AND METHODS: To determine the extent and distribution of disease, as well as associated anatomic abnormalities, computed tomography (CT) scans were performed on 113 children with persistent symptoms of sinusitis after failure of medical therapies. RESULTS: The maxillary sinus was the most commonly involved sinus, followed by the ethmoid, sphenoid, and frontal sinuses. There was no relationship between age and severity of sinusitis. Agger nasi cell was the most common anatomical variation, followed by septal deviation, Haller cell, concha bullosa, paradoxical middle turbinate, and Onodi cell. The prevalence of septal deviation increased with age. There was no significant relationship between the sinusitis and anatomic variations.

Adolescent↗
PubMed2005

Optic nerve injury secondary to endoscopic sinus surgery: an analysis of three cases.

Major orbital complications after the endoscopic sinus surgeries are rare and of these, optic nerve injury is one of the most serious. This study was to undertaken to analyze 3 cases of optic nerve injury after endoscopic sinus surgery. The three cases included one patient with a loss of visual acuity and visual field defect, and two patients with total blindness. In all cases, no improvement of visual acuity was observed despite treatment. It is important to frequently check the location and direction of the endoscope during surgery to avoid optic nerve injury. In addition, surgeons must have a precise knowledge of the detailed anatomy through cadaver dissections, an ability to interpret the PNS CT scan and experienced procedural surgical skills.

Adult↗
PubMed2004

Diplopia secondary to endoscopic sinus surgery.

OBJECTIVE: Diplopia after endoscopic sinus surgery (ESS) is rare but very serious. In this study, we investigated the characteristics, prognosis and treatment of diplopia occurring after ESS. MATERIAL AND METHODS: A retrospective analysis was carried out to investigate three patients with diplopia after ESS referred to us from other hospitals. RESULTS: In one case, an improvement in ocular motility was seen after surgical treatment. In the other cases, no improvement was observed, despite surgical treatment. CONCLUSION: In order to prevent diplopia after ESS, the surgeon must possess a complete anatomical knowledge obtained by means of cadaveric dissection, the ability to carefully read preoperative CT scans and the necessary surgical experience.

Adult↗
PubMed2003

Percutaneous transhepatic cholangioscopic treatment of patients with benign bilio-enteric anastomotic strictures.

BACKGROUND: Percutaneous transhepatic cholangioscopy is a nonoperative method for accessing bilio-enteric anastomotic strictures that cannot be reached via the transpapillary route. This study evaluated the immediate and long-term results of treatment via percutaneous transhepatic cholangioscopy of patients with benign bilio-enteric anastomotic strictures. METHODS: A retrospective analysis was conducted of 21 patients who, between October 1994 and March 2001, had undergone percutaneous transhepatic cholangioscopy for bilio-enteric anastomotic strictures. Follow-up ranged from 12 to 79 months (mean 33.3 months). RESULTS: The initial technical success rate was 100%, and the short-term morbidity and mortality rates were, respectively, 14.3% and 0%. However, strictures recurred in 8 patients (38.1%) at a mean of 17.1 months (range 2-38 months). The success rate exclusive of patients with recurrent strictures was 61.9%, and the overall success rate was 81.0% when the procedures were repeated. The long-term morbidity rate was 38.1%, but most complications resolved with conservative treatment. In 17 patients (81.0%), strictures were complicated by biliary stones, and these were successfully treated via percutaneous transhepatic cholangioscopy (stone removal rate 94.1%, recurrence rate 37.5%). CONCLUSIONS: Percutaneous transhepatic cholangioscopy-based treatment of patients with benign bilio-enteric anastomotic strictures is safe and effective. This minimally invasive method frequently can be used as a substitute for surgery.

Adult↗
PubMed2003

EUS in the evaluation of pancreatic cystic lesions.

BACKGROUND: The differential diagnosis in pancreatic cystic lesions is often difficult despite the availability of various modern imaging modalities. This study assessed the role of EUS in the following: (1) discrimination of pseudocysts from pancreatic cystic tumors, (2) differential diagnosis between serous cystadenoma and mucinous cystic tumor, and (3) prediction of accompanying malignancy in intraductal papillary mucinous tumor. METHODS: EUS findings in 75 patients with pancreatic cystic lesions (58 cystic tumors, 17 pseudocysts) were evaluated. In the comparison of pseudocysts and cystic tumors, the latter included intraductal papillary mucinous tumor, mucinous cystic tumors, and serous cystadenomas, but not solid-pseudopapillary tumors. RESULTS: In univariate analysis, pseudocysts exhibited echogenic debris and parenchymal changes more often than cystic tumors did (respectively, 29% vs. 6%, p < 0.05; and 65% vs. 4%, p < 0.001). In contrast, septa and mural nodules were found more frequently in cystic tumors than pseudocysts (respectively, 69% vs. 12%, p < 0.001; 56% vs. 12%, p < 0.01). Multivariate analysis revealed that parenchymal changes (odds ratio [OR] = 83.59; p < 0.01); septa (OR = 30.75; p < 0.05); and mural nodules (OR = 21.38; p < 0.05) were independent predictors of differentiation between pseudocysts and cystic tumors. Serous cystadenoma exhibited diverse EUS features, as well as a honeycomb appearance. Mural nodules were found more often in mucinous cystic tumors than in serous cystadenomas (p < 0.05). There were no factors that predicted malignancy in intraductal papillary mucinous tumor. CONCLUSIONS: EUS is a useful complementary imaging method for differentiation of pancreatic cystic lesions.

Adult↗
PubMed2003

Ectopic opening of the common bile duct in the duodenal bulb: clinical implications.

BACKGROUND: An ectopic opening of the common bile duct in the duodenal bulb is extremely rare, and the clinical significance of this anomaly has not been clarified. This study analyzed the clinical implications and cholangiographic findings of this anomaly. METHODS: A total of 18 patients (15 men, 3 women; median age, 51 years) with an ectopic opening of the common bile duct in the duodenal bulb were studied. Medical records, endoscopic findings, and cholangiographic and other radiographic findings were reviewed. RESULTS: All 18 patients had biliary pain; 7 had fever and chills. Fifteen (83%) had diffuse dilatation of the extrahepatic bile ducts with or without intrahepatic bile duct dilation. Associated bile duct stones were found in 10 (56%) patients. The papilla in the bulb had an orifice stained with bile at endoscopy, which was associated with duodenal ulcer disease found in 13 (72%) patients. The distal end of the common bile duct was tapered and narrowed and had a hook shape in all patients. CONCLUSION: An ectopic opening of the common bile duct in the duodenal bulb may be associated with clinical entities such as recurrent or intractable duodenal ulcer, choledocholithiasis, or acute cholangitis. Although these openings are rare, knowledge of the endoscopic and radiographic findings of an ectopic opening of the common bile duct in the duodenal bulb may help to clarify the cause of chronic recurrent duodenal ulcer disease in some patients and prevent damage to the bile duct during surgery.

Adult↗
PubMed2003

Idiopathic acute pancreatitis.

After routine investigations, including a thorough history, routine laboratory study, and noninvasive imaging with transcutaneous ultrasonogram, 10% to 25% of cases of acute pancreatitis have no readily identifiable cause and are termed idiopathic. But modern medicine has made notable advances in uncovering various causes of acute pancreatitis, and several new diagnostic tools that allow clinicians to less invasively approach the patient without sacrificing the diagnostic yield have been introduced. By being knowledgeable of these new changes and by their proper use in a proper circumstances, clinicians will be able to find the cause more accurately and earlier. This better management will not only improve the well-being of the patients but also reduce the number of "true" idiopathic acute pancreatitis to a minimum.

Acute Disease↗
PubMed2003

[Clinical characteristics and malignant predictive factors in patients with nonfunctioning islet cell tumors of the pancreas].

BACKGROUND/AIMS: It is difficult to determine preoperatively whether nonfunctioning islet cell tumors (NFICTs) are malignant or benign. The purposes of this study were to evaluate clinical characteristics and to differentiate benign from malignant behavior of NFICTs. METHODS: We retrospectively analyzed 21 patients with NFICTs between 1990 and 2002. RESULTS: Mean age was 51.4+/-13.2 years and female was predominant. Tumor size ranged from 0.5 to 13 cm (average 3.3+/-1.8 cm). Thirteen patients had variable symptoms. Histologically, 14 tumors were malignant and 7 were benign. In 9 out of 13 patients, pancreatogram showed narrowing of the main pancreatic duct, which was more frequently detected in patients with malignant NFICTs than in patients with benign ones (p<0.01). Surgical resection was performed in 20 patients. All patients with benign NFICTs are still alive after surgery, while 3 out of 14 patients with malignant NFICTs died 11, 22, 30 months after operation or diagnosis, respectively. The follow up time ranged from 1 to 111 months (mean 32.6 months) CONCLUSIONS: The presenting symptoms of patients with NFICTs were non-specific. The malignancy rate of NFICTs was high. Narrowing of the main pancreatic duct on pancreatogram suggested the malignancy.

Adenoma, Islet Cell↗
PubMed2003

[Usefulness and limitation of magnetic resonance cholangiopancreatography in patients with hepatolithiasis].

BACKGROUND/AIMS: Diagnosis of bile duct strictures as well as detection and localization of hepatolithiasis is important for an effective treatment of hepatolithiasis. For this purpose, endoscopic retrograde cholangiopancreatography (ERCP) and percutaneous transhepatic cholangiography (PTC) have been preferred as the diagnostic modalities of choice for hepatolithiasis. At present, magnetic resonance cholangiopancreatography (MRCP) is rapidly replacing ERCP. To determine the usefulness and limitation of MRCP for detecting hepatolithiasis and biliary strictures, we compared the result of MRCP with that of percutaneous transhepatic cholangioscopy (PTCS) as the standard reference. METHODS: Sixty-six patients with primary hepatolithiasis who underwent both MRCP and PTCS were enrolled. All patients underwent PTCS within 2 weeks of MRCP. The results of MRCP were reviewed by radiologists who were unaware of the clinical information about the location of hepatolithiasis and the presence of biliary strictures. RESULTS: The sensitivity and specificity of MRCP for detecting intrahepatic stones were 72.4 and 90%, respectively. The sensitivity of MRCP for depicting intrahepatic bile duct strictures was 64%. The overall agreement between MRCP and PTCS for intrahepatic stones showed a good reliability (kappa value=0.64, p<0.05). The agreement of MRCP for hepatolithiasis with intrahepatic bile duct strictures with reference to PTCS showed a moderate reliability (kappa value=0.47, p<0.05). Imaging findings such as pneumobilia and hepatic parenchymal atrophy were related to false positive results in location of hepatolithiasis (p<0.05). CONCLUSIONS: MRCP has a good agreement rate in evaluation of intrahepatic stones and a moderate agreement rate in intrahepatic strictures, compared to PTCS.

Adult↗
PubMed2002

IL-13 suppresses MUC5AC gene expression and mucin secretion in nasal epithelial cells.

Recently, it was found that IL-13 is involved in allergic inflammation and mucus hypersecretion in in vivo animal models. However, the role of IL-13 in in vitro cellular models has yet to be determined. This study aimed to investigate the direct effect of IL-13 on mucin gene expression and mucin secretion in cultured normal human nasal epithelial cells. After treatment with IL-13, total mucin and MUC5AC mucin levels were measured using an immunoblotting assay. MUC2, MUC5AC and MUC8 mRNA expression were determined using reverse transcription-polymerase chain reaction. Also, immunostaining was performed using a MUC5AC antibody on histologic and cytospin slides. After treatment with > or = 5 ng/ml IL-13, the level of total mucin and MUC5AC mucin secretion decreased substantially. The expression of MUC2 and MUC8 mRNA increased with higher concentrations of IL-13, but the expression of MUC5AC mRNA decreased. On the 7th day after IL-13 treatment, a significant decrease in the number of MUC5AC-positive cells was confirmed by immunostaining. These findings indicate that IL-13 suppresses MUC5AC mucin gene expression and mucin secretion in cultured normal human nasal epithelial cells in vitro.

Cell Count↗
PubMedDate not supplied

The risk of olfactory disturbance from conchal plate injury during ethmoidectomy.

BACKGROUND: Even though the olfactory function usually is improved or unchanged after ethmoidectomy, some patients complain of olfactory disturbance, which may be caused by direct injury to the olfactory nerves. However, the detailed anatomic pathway of the olfactory nerves that leave the olfactory mucosa and after going through the cribriform plate insert into the olfactory bulb is uncertain. In the studies of lateral nasal wall, we referred to the thin bone that connects the middle, superior, and supreme turbinates to the skull base as the "conchal plate." We undertook this study to determine the anatomic relation between the conchal plate and the olfactory nerve. METHODS: Ten midsagittal sections from adult cadaver head specimens were used for gross anatomy and the midportion of the conchal plate was taken and fixed in 10% formalin. The microscopic structures of the conchal plate were observed after hematoxylin and eosin staining. RESULTS: The olfactory nerves originated from the olfactory mucosa lining the middle and superior turbinates and ran upward within the bone of the conchal plate. These results suggest that the olfactory nerve may be injured inadvertently in the conchal plate during ethmoidectomy and that this injury is likely to be one of the possible causes of olfactory disturbance. CONCLUSION: We propose a possibility that injury to the conchal plate can affect olfactory function. Therefore, care should be taken to avoid damage to the conchal plate during ethmoidectomy.

Adult↗
PubMedDate not supplied

Multislice CT cholangiography using thin-slab minimum intensity projection and multiplanar reformation in the evaluation of patients with suspected biliary obstruction: preliminary experience.

Thirty-three patients with suspected biliary obstruction were prospectively evaluated with multislice CT cholangiography using thin-slab minimum intensity projection (MinIP) and multiplanar reformation (MPR) to determine its usefulness and to compare with the comparative studies of endoscopic retrograde cholangiography (ERC), magnetic resonance cholangiography (MRC), or percutaneous transhepatic cholangiography (PTC). CT cholangiography made correct diagnoses in all biliary obstructions except in two patients with common bile duct stones. The correspondence with the comparative study was 93.9%. Multislice CT cholangiography may be favorable in noninvasive evaluation of biliary obstructions.

Bile Duct Diseases↗