2.The effect of fluoride-containing oral rinses on the corrosion resistance of titanium alloy (Ti-6Al-4V).
Gui Yue HUANG ; Heng Bo JIANG ; Jung Yul CHA ; Kwang Mahn KIM ; Chung Ju HWANG
The Korean Journal of Orthodontics 2017;47(5):306-312
OBJECTIVE: The purpose of this study was to examine the effect of commercially available fluoride-containing oral rinses on the corrosion behavior of titanium alloys, which are the main components of orthodontic miniscrews. METHODS: Four commercially available oral rinses (solution A, pH 4.46/260 ppm fluoride; solution B, pH 4.41/178 ppm fluoride; solution C, pH 6.30/117 ppm fluoride; and solution D, pH 4.17/3.92 ppm fluoride) were tested on titanium alloy (Ti-6Al-4V) circular plates, and saline was used as the control. The open-circuit potential and potentiodynamic polarization of these materials were measured. Thereafter, all samples were evaluated under a field-emission scanning electron microscope. RESULTS: Among the tested oral rinses, except solution D, the more the fluoride content was, the greater was the corrosion potential downtrend; the corrosion resistance of the titanium alloy sample was also lowered significantly (p < 0.05). Field-emission scanning electron microscopic analysis of the surface morphology of the titanium alloy samples revealed that all samples had some defects, crevices, or pitting after exposure to the oral rinses than before treatment. In particular, the samples in solution A showed the most changes. CONCLUSIONS: Commercially available oral rinses having a high fluoride concentration and a low pH may reduce the corrosion resistance of titanium alloys used in dental appliances such as orthodontic titanium miniscrews and brackets.
Alloys*
;
Corrosion*
;
Fluorides
;
Hydrogen-Ion Concentration
;
Titanium*
3.Isolation of anaerobic bacteria from intraabdominal abscess and susceptibility to several beta-lactam antibiotics.
Byung Soo DO ; Gwang Yul SONG ; Jae Hwang KIM ; Hong Jin KIM ; Min Chul SHIM ; Koing Bo KWUN ; Hee Sun KIM ; Sung Kwang KIM
Journal of the Korean Society of Coloproctology 1991;7(1):15-21
No abstract available.
Abscess*
;
Anti-Bacterial Agents*
;
Bacteria, Anaerobic*
4.A Case of von Hippel-Lindau Disease Presenting with Pancreatic Neuroendocrine Tumor.
Jung Hun OHN ; Junghee KIM ; Hyun Jung LEE ; Won Woo SEO ; Yul HWANG-BO ; Eun Shil HONG ; Jin Joo PARK ; Seong Yeon KIM
Endocrinology and Metabolism 2011;26(1):89-91
Von Hippel-Lindau (VHL) disease is an autosomal dominant disorder that results from a germline mutation of the VHL gene. The affected individuals might develop several benign or malignant tumors such as central nervous system or retinal haemangioblastomas, endolymphatic sac tumors, renal cell carcinomas, pheochromocytomas or pancreatic cysts and neuroendocrine tumors. We report here on a case of a 21 year old female with von Hippel-Lindau disease and she presented with only pancreatic neuroendocrine tumor and no evidence of haemangioblastomas or other visceral complications. Further, direct sequencing of the VHL gene reveals a novel germline frameshift mutation of codon 198 from the deletion of nucleotide 592 (cytosine), leading to truncation of the VHL protein.
Carcinoma, Renal Cell
;
Central Nervous System
;
Codon
;
Endolymphatic Sac
;
Female
;
Frameshift Mutation
;
Germ-Line Mutation
;
Humans
;
Neuroendocrine Tumors
;
Pancreas
;
Pancreatic Cyst
;
Pheochromocytoma
;
Retinaldehyde
;
von Hippel-Lindau Disease
5.Association of the Parathyroid Adenoma Volume and the Biochemical Parameters in Primary Hyperparathyroidism.
Yul HWANG-BO ; Jung Hee KIM ; Jee Hyun AN ; Eun Shil HONG ; Jung Hun OHN ; Eun Ky KIM ; Ah Reum KHANG ; Sun Wook CHO ; Do Joon PARK ; Kyong Soo PARK ; Seong Yeon KIM ; Bo Youn CHO ; Chan Soo SHIN
Endocrinology and Metabolism 2011;26(1):62-66
BACKGROUND: The objective of this study is to demonstrate the relationship between the volume of a parathyroid adenoma and the preoperative biochemical parameters in patients undergoing surgery for primary hyperparathyroidism. METHODS: The medical records of 68 patients who underwent a parathyroidectomy for a single parathyroid adenoma were retrospectively reviewed. The volume of the adenoma was estimated using its measured size and a mathematical formula. The correlation between the volume of the parathyroid adenoma and the preoperative laboratory data was assessed. RESULTS: There were no correlations between the estimated volume of the adenoma and the serum calcium, alkaline phosphatase and parathyroid hormone levels. However, the volume of the adenoma was associated with the preoperative level of serum phosphorus. After excluding 5 adenomas with cystic degeneration, a positive correlation was noted between the adenoma volume and the preoperative levels of alkaline phosphatase and parathyroid hormone. CONCLUSION: The preoperative serum levels of calcium, alkaline phosphatase and parathyroid hormone are of limited use to predict the volume of the parathyroid adenoma in patients with a single parathyroid adenoma. We suggest that the absence of a correlation between the volume of the adenoma and the biochemical parameters can be attributed to the cystic degeneration of the adenomas.
Adenoma
;
Alkaline Phosphatase
;
Calcium
;
Humans
;
Hyperparathyroidism
;
Hyperparathyroidism, Primary
;
Medical Records
;
Parathyroid Hormone
;
Parathyroid Neoplasms
;
Parathyroidectomy
;
Phosphorus
;
Retrospective Studies
6.Malignancy Rate in Sonographically Suspicious Thyroid Nodules of Less than a Centimeter in Size Does Not Decrease with Decreasing Size.
Yul Hwang BO ; Hwa Young AHN ; Yun Hee LEE ; Ye Jin LEE ; Jung Hee KIM ; Jung Hun OHN ; Eun Shil HONG ; Kyung Won KIM ; In Kyung JEONG ; Sung Hee CHOI ; Soo LIM ; Do Joon PARK ; Hak Chul JANG ; Byung Hee OH ; Bo Youn CHO ; Young Joo PARK
Journal of Korean Medical Science 2011;26(2):237-242
We evaluated the malignancy and nondiagnostic rates using fine needle aspiration cytology (FNAC) results in thyroid nodules smaller than 1 cm according to the subdivided size. We retrospectively reviewed the medical records of all subjects underwent FNAC from 2003 to 2009 in our hospital, and 2,756 patients of subcentimeter thyroid nodules with one or more suspicious sonographic features and 7,105 with nodule sized 1 cm or more were included. The malignancy rate was higher in those subcentimeter nodules with suspicious sonographic findings than the nodule sized 1cm or more (19.7% vs 7.8%, P < 0.001). We grouped the nodules based on size with mm interval and observed that the malignancy rate did not decrease but the nondiagnostic results increased its size decrement. When we divided the subjects arbitrarily into a 5 mm or smaller and a 6-9 mm sized group, nondiagnostic cytology findings were reported more frequently in the smaller group (24.3% vs 18.1%, P = 0.001), while the rate of "malignant" was similar (18.3% vs 15.5%, P = 0.123) and the rate of "suspicious for malignancy" was higher (6.8% vs 2.9%, P < 0.001). Therefore when we decide to perform FNAC or not in subcentimeter-sized nodules, we should consider sonographic findings and other clinical risk factors but not the nodular size itself.
Adult
;
Biopsy, Fine-Needle
;
Female
;
Humans
;
Male
;
Middle Aged
;
Retrospective Studies
;
Risk Factors
;
Thyroid Gland/pathology/ultrasonography
;
Thyroid Neoplasms/diagnosis/*pathology/*ultrasonography
;
Thyroid Nodule/diagnosis/*pathology/*ultrasonography
7.Investigation of Sarcopenia and Its Association with Cardiometabolic Risk Factors in Elderly Subjects.
Jung Hee KIM ; Yul HWANG BO ; Eun Shil HONG ; Jung Hun OHN ; Chi Hoon KIM ; Hye Won KIM ; Hwa Young AHN ; Ji Won YOON ; Seon Mee KANG ; Young Joo PARK ; Hak Chul JANG ; Soo LIM
Journal of the Korean Geriatrics Society 2010;14(3):121-130
BACKGROUND: The aim of this study was to investigate sarcopenia and its association with cardiometabolic risk factors in a community-based elderly cohort in Korea. METHODS: We recruited 287 men and 278 women aged 65 years or older and without physical disability. Appendicular skeletal muscle mass (ASM) was measured with dual energy X-ray absorptiometry. We used two definitions for sarcopenia-ASM divided by height2 (kg/m2) or by weight (%) <1 SD below the sex-specific mean for young adults. We compared RBP-4, adiponectin, hsCRP, lipid profiles, and insulin resistance between the sarcopenic and normal groups using ASM/Ht2 and ASM/Wt. RESULTS: The prevalence of sarcopenia was 35.3% in men and 13.4% in women with sarcopenia defined by ASM/Ht2. However, it was 38.3% in men and 62.6% in women by ASM/Wt. In correlation analysis, body mass index was positively correlated with ASM/Ht2 and negatively correlated with ASM/Wt. The sarcopenic group, when defined as ASM/Ht2, showed lower RBP4, fasting plasma glucose, and HOMA-IR and higher adiponectin than the normal group but not significantly different lipid profiles. The sarcopenic group defined by ASM/Wt had higher RBP4, fasting plasma glucose, and HOMA-IR, and lower adiponectin than the normal group in both sexes. Only in the males did the sarcopenic group defined by ASM/Wt reveal higher total cholesterol, triglycerides, and LDL cholesterol, and lower HDL cholesterol than the normal group. CONCLUSION: In conclusion, the sarcopenic group defined by ASM/Wt was more closely associated with cardiometabolic risk factors than the normal group in a community-based elderly cohort.
Absorptiometry, Photon
;
Adiponectin
;
Aged
;
Body Mass Index
;
Cholesterol
;
Cholesterol, HDL
;
Cholesterol, LDL
;
Cohort Studies
;
Fasting
;
Female
;
Glucose
;
Humans
;
Insulin Resistance
;
Korea
;
Male
;
Muscle, Skeletal
;
Plasma
;
Prevalence
;
Risk Factors
;
Sarcopenia
;
Triglycerides
;
Young Adult
8.Clinical Characteristics of Langerhans Cell Histiocytosis with Hypothalamo-Pituitary Involvement.
Eun Shil HONG ; Jung Hun OHN ; Jung Hee KIM ; Yul HWANG-BO ; Jin Joo KIM ; Jung Hee KWON ; Jung Won LEE ; Se Youn CHOI ; Eun Kyung LEE ; Sun Wook CHO ; Chan Soo SHIN ; Kyong Soo PARK ; Hak Chul JANG ; Bo Youn CHO ; Hong Kyu LEE ; Choong Ho SHIN ; Sei Won YANG ; Seong Yeon KIM
Endocrinology and Metabolism 2011;26(1):38-43
BACKGROUND: Langerhans cell histiocytosis (LCH) is a rare disease that involves a clonal proliferation of Langerhans cells. LCH has a predilection for hypothalamo-pituitary axis (HPA) dysfunction, and this leads to diabetes insipidus (DI) and/or anterior pituitary dysfunction. Here, we describe the endocrine dysfunction and clinical characteristics of adult patients with LCH and we analyzed the differences between an adult-onset type and a childhood-onset type. METHODS: The data was obtained from a retrospective chart review of the patients with LCH that involved the HPA and who attended Seoul National University Hospital. The patients were classified into the adult-onset type (age at the time of diagnosis > or = 16) and the childhood-onset type (age at the time of diagnosis < or = 15). RESULTS: Ten patients (9 males and 1 female) were diagnosed with LCH involving the HPA. Five patients were classified as an adultonset type and the other five patients were classified as a childhood-onset type. The median follow-up duration was 6 (3-12) years for the adult-onset type and 16 (15-22) years for the childhood-onset type. All the patients presented with DI as the initial manifestation of HPA involvement. Four adult-onset patients and three childhood-onset patients had a multi-system disease. Panhypopituitarism developed in three adult-onset patients and in one childhood-onset patient. The pituitary lesion of the three adult-onset patients had spread to the brain during the follow-up duration. In contrast, the pituitary lesion of the other two adult-onset patients without panhypopituitarism and all the childhood-onset patients had not changed. CONCLUSION: DI was the initial presentation symptom of HPA involvement. Anterior pituitary hormone deficiency followed in some patients. Compared with the childhood-onset patients, the adult-onset patients were more likely to have panhypopituitarism and a poor prognosis.
Adult
;
Brain
;
Diabetes Insipidus
;
Follow-Up Studies
;
Histiocytosis, Langerhans-Cell
;
Humans
;
Hypopituitarism
;
Langerhans Cells
;
Male
;
Prognosis
;
Rare Diseases
;
Retrospective Studies
;
Axis, Cervical Vertebra