1.Mechanisms of Increase in Renal Blood Flow During Partial Ureteral Obstruction in Dogs.
Hun Mo YANG ; Young Gi MIN ; Jae Eung YOO
Korean Journal of Nephrology 1998;17(5):686-691
Although tubuloglomerular feedback (TGF) is involved in ureteral obstruction-induced increase in renal blood flow (RBF), its contribution to RBF is not well established due to the concommitant increases in prostaglandin (PG) and renal interstitial fluid pressure (Pisf), both of which affect RBF one way or the other. Since Pisf and TGF are closely affected by renal hemodynamics, RBF will respond differently to increases in ureteral pressure depending on renal hemodynamic conditions. Therefore, the purpose of the present study was to investigate how the changes in renal hemodynamics affect the response of RBF to increases in ureteral pressure. The effect of PG on RBF was assessed by comparing the effects obtained before and after indomethacin, a cyclooxygenase inhibitor. Six anesthetized dogs were prepared with flow probes and inflatable silastic occluder around the renal artery, the ureteral catheter with its free end attached to a water reservoir, and the arterial and venous catheters. RBFs were obtained at ureteral pressures of 0, 15, and 40cmH2O during the maintenance of the renal artery pressure (RAP) at the level of systemic arterial pressure, 10mmHg above and below the lower autoregulatory limit of RBF (65+/-4 mmHg) both before and after indomethacin administration (10mg/kg). In response to the ureteral pressure of 40cmH2O, RBF increased from 172+/-6 to 185+/-10ml/min when RAP's were equal to systemic arterial pressure and decreased from 162+/-10 to 120+/-9 ml/min when RAP's were 55+/-4mmHg. Indomethacin pretreatment, depending on the level of RAP either prevented an increase or augmented a decrease in RBF in response to ureteral pressure elevation. This suggests that RAP-dependent changes in susceptibility of the renal venous system to compression by increased Pisf is the main mechanism by which the changes in renal perfusion pressure modulate the response of RBF to ureteral pressure elevation.
Animals
;
Arterial Pressure
;
Catheters
;
Dogs*
;
Extracellular Fluid
;
Hemodynamics
;
Indomethacin
;
Perfusion
;
Prostaglandin-Endoperoxide Synthases
;
Renal Artery
;
Renal Circulation*
;
Ureter*
;
Ureteral Obstruction*
;
Urinary Catheters
;
Water
2.Outbreak of Nosocomial Urinary Tract Infections caused by Multidrug-Resistant Pseudomonas aeruginosa.
Yeon Joon PARK ; Eun Jee OH ; Gi Bum KIM ; So Yeon KIM ; Sung Taek KIM ; So Yeon YOO ; Yang Ree KIM ; Moon Won KANG ; Byung Kee KIM
Korean Journal of Nosocomial Infection Control 1999;4(1):1-6
BACKGROUND: Nosocomial urinary tract infection (UTI) accounts for 35% of the nosocomial infection and 80-90% of them are associated with urethral catheters. Recently, we experienced an outbreak of nosocomial UTI caused by multidrug-resistant Pseudomonas aeruginosa in neurosurgical intensive care unit (NSICU). METHODS: We investigated clinical records of the patients and observed the methods of care of urethral catheters in NSICU. Identification of P. aeruginose was done by API NE (API system; bioMerieux, France) and antibiotic susceptibility tests were done by disk diffusion method. Random Amplification of Polymorphic DNA (RAPD) assay was used as a genotyping method. RESULTS: Between November 1997 and January 1998, 11 P. aeruginosa strains were isolated from the urine of 11 patients hospitalized in NSICU of Kangnam St. Mary's Hospital. Routine regular bladder irrigation, and emptying urine with common urinal had been done falsely. Antibiogram of the isolates showed resistance to multiple antibiotics including imipenem, gentamicin. amikacin, piperacillin, ciprofloxacin, ceftazidime, and cefoperazone/sulbactam. RAPD of the outbreak strains showed clonal relatedness, which was different from those of other clinical strains, We instructed all the health care workers to stop bladder Irrigation, and to use the separate urinals for each patient. Thereafter, no further case of P. aeruginosa UTI has occurred. CONCLUSION: An outbreak of UTI, caused by a single clone of P. aeruginosa, was confirmed by RAPD and was eradicated after correction of false practice on care-of urinary catheter.
Amikacin
;
Anti-Bacterial Agents
;
Ceftazidime
;
Ciprofloxacin
;
Clone Cells
;
Cross Infection
;
Delivery of Health Care
;
Diffusion
;
DNA
;
Drug Resistance, Multiple
;
Gentamicins
;
Humans
;
Imipenem
;
Intensive Care Units
;
Microbial Sensitivity Tests
;
Piperacillin
;
Pseudomonas aeruginosa*
;
Pseudomonas*
;
Urinary Bladder
;
Urinary Catheters
;
Urinary Tract Infections*
;
Urinary Tract*
3.Histological Evaluation of Bone Ingrowth around Titanium and Hydroxyapatite-coated Titanium Implant in Dogs.
Taek Rim YOON ; Sung Taek JUNG ; Sun Ju YANG ; Kyung Yeon YOO ; Seung Gi LEE ; Yoon Ho SON
Journal of Korean Orthopaedic Research Society 1998;1(1):57-67
Since the concept of osseointegration has been introduced, a lot of researches were performed to achieve stronger fixation of the implant. In this study, we tried to find the different pattern of bone ingrowth after implanting pure titanium implant and Hydroxyapatite coated titanium implant in dogs. Four typed of cylindrical titanium implants (diameter 6 mm, length 1 mm) were inserted in the distal femur of adult dogs. The histological examination was done at postoperative 2, 4, 8, and 12 weeks. There was no foreign body reaction at contact site and all implants kept direct contact with bone tissue. In the light microscopic finding, after 2 weeks, the cases with Hydroxyapatite-coated Implant (HAP) showed greater formation of immature woven bone in comparison to Titanium implant. After 4 weeks, Hydroxyapatite-coated Implant (HAP) showed more mature lamellar bone. After 8 and 12 weeks, most of the woven bone was transformed into mature lamellar bone. The fluorescence microscopic finding, after 2 weeks, revealed calcein green fluorescence around implants in all cases and it was more prominent in the cases with Hydroxyapatite-coated Implant (HAP). After 4 weeks, the center of trabecula gave out green fluorescent light, the corner of them showed red fluorescent light, and they were more prominent in the cases with Hydroxyapatite-coated Implant (HAP). After 8 and 12 weeks, green fluorescence disappeared gradually, red fluorescence appeared for the most part, and there was no difference in each cases, especially in 12 weeks. As a result, we support the concept that Hydroxyapatite-coated Implant (HAP) induces faster bone ingrowth in 4 weeks than Titanium implant, and that it may be more profitable for early bone ingrowth and implant stability.
Adult
;
Animals
;
Bone and Bones
;
Dogs*
;
Durapatite
;
Femur
;
Fluorescence
;
Foreign-Body Reaction
;
Humans
;
Osseointegration
;
Titanium*
4.Cholesterol embolism associated with acute renal failure after coronary angiography.
Hyeong Ho KIM ; Mi Kyeong KIM ; Jae Hyuk JUNG ; Doo Ryeon JUNG ; Won Seok YANG ; Jong Koo LEE ; Chang Gi HONG ; Eun Sil YOO
Korean Journal of Nephrology 1993;12(3):464-469
No abstract available.
Acute Kidney Injury*
;
Cholesterol*
;
Coronary Angiography*
;
Embolism, Cholesterol*
5.Development of New Device to Improve Sucess Rate of Maze Procedure with Radiofrequency Energy.
Nam Hee PARK ; Yang gi YOO ; Jae Won LEE
The Korean Journal of Thoracic and Cardiovascular Surgery 2004;37(6):467-473
BACKGROUND: The sinus conversion rate after the maze procedure in chronic atrial fibrillation using radiofrequency energy is lower than with either conventional 'cut and saw' technique or cryothermia. The creation of incomplete transmural lesions due to poor tissue-catheter contact is thought to be the main cause. To address this problem, the current study was aimed to evaluate the effectiveness of a specially constructed compression device designed to enhance tissue catheter contact during unipolar radiofrequency catheter ablation. MATERIAL AND METHOD: Circumferential right auricular epicardial lesions were created with a linear radiofrequency catheter in 10 anesthetized pigs. A device specially designed to increase contact by compression of the catheter to the atrial wall was used in 5 pigs (study group). This device was not used in the control group (5 pigs). Conduction block across the right auricular lesion was assessed by pacing, and the transmurality of the lesions were confirmed by microscopic examination. RESULT: Conduction block was observed in a total of 8 pigs; 5 in study group and 3 in control group. Transmural injury was confirmed microscopically by the accumulation of acute inflammatory cells and loss of elastic fibers in the endocardium. In two pigs with failed conduction block, microscopic examination of the endocardium appeared normal. CONCLUSION: Failed radiofrequency ablation is strongly related to non-transmural energy delivery. The specially constructed compression device in the current study was successful in creating firm tissue-catheter contact and thereby generating transmural lesions during unipolar radiofrequency ablation.
Atrial Fibrillation
;
Catheter Ablation
;
Catheters
;
Elastic Tissue
;
Endocardium
;
Equipment Design
;
Swine
6.Rhabdomyolysis associated with lovastatin-cyclosporine combination therapy : report of three cases in kidney transplant recipients.
Ki Dong YOO ; Won Young LEE ; Gi Won PARK ; Chul Woo YANG ; Dong Chan JIN ; Sun Ae YOON ; Young Suk YOON ; Byung Kee BANG
Korean Journal of Nephrology 1993;12(4):715-719
No abstract available.
Kidney*
;
Rhabdomyolysis*
;
Transplantation*
7.Comparison of suicide and self-harm characteristics before and after the COVID-19 outbreak in South Korea
Hyeonbeom BYEON ; Heewon YANG ; Yoo Jin CHOI ; Hyukhoon KIM ; Young-Gi MIN
Journal of the Korean Society of Emergency Medicine 2023;34(4):314-322
Objective:
This study analyzed patients who visited emergency departments (EDs) following suicide and self-harm attempts to determine the impact of the coronavirus disease 2019 (COVID-19) on suicide and self-harm trends.
Methods:
This study retrospectively collected the data of patients who visited five EDs following suicide and self-harm attempts before (March to December 2019) and after (March to December 2020) the COVID-19 outbreak using the National Emergency Department Information System database in South Korea.
Results:
In this study, 2,333 and 2,303 patients visited EDs following suicide and self-harm attempts before and after COVID-19, respectively. The number of females was 1,421 versus 1,490 (P=0.008), and the number of those in their twenties (20s) was 576 versus 705 (P<0.001), respectively. The proportion of patients with suicide attempts increased after the outbreak (1.0 vs. 0.7%; P=0.009). The severity scores on the Korean Triage and Acuity Scale (KTAS) levels 1 and 2 decreased-before 169 (7.2%) and 633 (27.1%); after 144 (6.3%) and 525 (22.8%); P=0.003. The outcomes of patients following hospital admission were significantly different in terms of increased safe discharge numbers, decreased discharges against medical advice and transfers to other hospitals, and fewer deaths during admission.
Conclusion
During the COVID-19 outbreak, there were notable characteristic changes in the rate of suicide attempts in young adults, with the decreased severity of suicide and self-harm among the patients who visited EDs.
8.Effect of Microalgal Extracts of Tetraselmis suecica against UVB-Induced Photoaging in Human Skin Fibroblasts.
Wol Soon JO ; Kwang Mo YANG ; Hee Sung PARK ; Gi Yong KIM ; Byung Hyouk NAM ; Min Ho JEONG ; Yoo Jin CHOI
Toxicological Research 2012;28(4):241-248
Exposure of cells to ultraviolet B (UVB) radiation can induce production of free radicals and reactive oxygen species (ROS), which damage cellular components. In addition, these agents can stimulate the expression of matrix metalloproteinase (MMP) and decrease collagen synthesis in human skin cells. In this study, we examined the anti-photoaging effects of extracts of Tetraselmis suecica (W-TS). W-TS showed the strongest scavenging activity against 2,2-difenyl-1-picrylhydrazyl (DPPH) and peroxyl radicals, followed by superoxide anions from the xanthine/xanthine oxidase system. We observed that the levels of both intracellular ROS and lipid peroxidation significantly increased in UVB-irradiated human skin fibroblast cells. Furthermore, the activities of enzymatic antioxidants (e.g., superoxide dismutase) and the levels of non-enzymatic antioxidants (e.g., glutathione) significantly decreased in cells. However, W-TS pretreatment, at the maximum tested concentration, significantly decreased intracellular ROS and malondialdehyde (MDA) levels, and increased superoxide dismutase and glutathione levels in the cells. At this same concentration, W-TS did not show cytotoxicity. Type 1 procollagen and MMP-1 released were quantified using RT-PCR techniques. The results showed that W-TS protected type 1 procollagen against UVB-induced depletion in fibroblast cells in a dose-dependent manner via inhibition of UVB-induced MMP-1. Taken together, the results of the study suggest that W-TS effectively inhibits UVB-induced photoaging in skin fibroblasts by its strong anti-oxidant ability.
Antioxidants
;
Collagen
;
Fibroblasts
;
Free Radicals
;
Glutathione
;
Humans
;
Lipid Peroxidation
;
Malondialdehyde
;
Oxidoreductases
;
Procollagen
;
Reactive Oxygen Species
;
Skin
;
Superoxide Dismutase
;
Superoxides
9.A Case of Transvaginal Expulsion of Intramural Leiomyoma after Uterine Artery Embolization.
Seung Jun PARK ; Gi Young KIM ; Sang Hwak HAN ; Jeong Bum CHOI ; Sin Hye KIM ; Ji Hoon YOO ; Hwan Sung JOE ; Hyo Sang HAN ; In Cheul HWANG ; Seung Boo YANG
Korean Journal of Obstetrics and Gynecology 2006;49(11):2438-2444
Uterine artery embolization for the treatment of uterine leiomyomas is gaining acceptance as an effective alternative to surgical treatment in preserving uterus and reducing symptoms. Vaginal expulsion of leiomyomas after UAE is uncommon, and has been regarded as a side effect of the procedure, as well as a natural phenomenon of treatment response. A-28-year-old unmarried woman who has been suffered from menorrhagia underwent UAE. MRI revealed the remnant leiomyomas were reduced in size and volume and also symptoms of leiomyomas were much improved. After 6 month, We've made sure about non-visualization of leiomyoma on follow-up pelvic dynamic MRI. We report this rare case of vaginal expusion of intramural leoimyoma with a brief literature.
Female
;
Follow-Up Studies
;
Humans
;
Leiomyoma*
;
Magnetic Resonance Imaging
;
Menorrhagia
;
Single Person
;
Uterine Artery Embolization*
;
Uterine Artery*
;
Uterus
10.A case report: A case of fibroepithelial polyp on vulvoperineal area.
Kyung Do KI ; Seon Kyung LEE ; Dong Kyu NOH ; Sang Gi SEO ; Moon Ho YANG ; Yoon Wha KIM ; Young Chun YOO
Korean Journal of Obstetrics and Gynecology 2005;48(2):505-508
A case of fibroepithelial polyp on vulvoperineal area is described. Her age is 20 year old and the tumor measured 9 cm in its largest diameter and was connected to the left labium majus. This case is very unusual in that almost all reported vulvar fibroepithelial polyps are small and sessile, and should distinguish from malignant cancer. We have experienced an unusually large vulvoperineal mass that was surgically excised and histologically diagnosed as benign fibroepithelial polyp and present this case with a brief review of literature.
Humans
;
Polyps*
;
Young Adult