1.Histopathologic Reactions of Normal Tissues after Percutaneous Injection of Hot Saline: an Experimental Study in Pigs.
Hyun Ki YOON ; Ho Young SONG ; Sangsoo PARK ; Sang Woo SONG ; Kyung Hoon KANG ; Kyu Bo SUNG
Journal of the Korean Radiological Society 2000;42(3):447-452
PURPOSE: To determine the histopathologic changes occurring in normal pig organs after percutaneous injection of hot saline. MATERIALS AND METHODS: Under sonographic guidance, the livers, the gallbladders, kidneys, stomachs, and lungs of ten pigs weighing 15-20kg were punctured with a fine needle. Physiologic saline mixed with contrast medium and Lipiodol was heated to 100 degreeC and injected under fluoroscopic guidance. One to four weeks after injection, the animals were sacrificed and histopathologic examination was performed to investigate acute and chronic tissue responses. RESULTS: In all organs, coagulation necroses developed during the acute phase. Histopathologic changes observed four weeks after injection were as follows: in the liver, most damage was restored, though central necrosis persisted; in the kidney, parenchymal and uroepithelial damage fully recovered, and in the gallbladder and stomach, superficially located damage also fully recovered. In the lung, however, extensive pneumonic infiltration developed during the chronic phase. Fluoroscpoic examination revealed that saline in the liver or kidneys tended to leak easily into blood vessels, the bile duct, or ureter, and corresponding regions showed mild to moderate damage during the acute phase which fully recovered in the chronic phase. CONCLUSION: In normal pigs, significant chronic damage after the injection of hot saline mixture occurred only in the lungs.
Animals
;
Bile Ducts
;
Blood Vessels
;
Ethiodized Oil
;
Gallbladder
;
Hot Temperature
;
Kidney
;
Liver
;
Lung
;
Necrosis
;
Needles
;
Stomach
;
Swine*
;
Ultrasonography
;
Ureter
2.Invention of a Nasolacrimal Stent Retrieval Hook.
Tae Hyung KIM ; Yeong Kyun KIM ; Sangsoo PARK ; Ho Young SONG
Journal of the Korean Radiological Society 1997;37(1):59-62
PURPOSE: To evaluate the clinical usefulness of a nasolacrimal stent retrieval hook. MATERIALS AND METHODS:The retrieval hook consisted of two parts, a hook and pusher. The head of the hook part was made of 0.7 mm stainless steel wire and was question mark-spaped, while the body of this part was constructed by soldering together four stainless steel pipes ranging in thickness from 1.25 to 3.5 mm, serially. The pusher part was made of two plastic tubes and was designed in such a way that the hook grasped the stent tightly. The device was used to remove 46 stents in 40 patients, and tested for 1) average number of trials ; 2) success rate; and 3) average time of the procedure. RESULTS: The average number of trials, success rate, and average time taken to remove the stent was 4.7, 91%, and 1.8 minutes, respectively. CONCLUSION: In the removal of nasolacrimal stents, the retrieval hook was easy to use, useful and effective.
Hand Strength
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Head
;
Humans
;
Inventions*
;
Plastics
;
Stainless Steel
;
Stents*
3.Medical professionalism among emergency physicians in South Korea: a survey of perceptions and experiences of unprofessional behavior
Sangun NAH ; Sangsoo HAN ; Kyunghye PARK ; Chanwoong KIM ; Hyun NOH ; Eunkyung EO
Clinical and Experimental Emergency Medicine 2022;9(1):54-62
Objective:
The purpose of this study was to analyze the current situation concerning professionalism among emergency physicians in South Korea by conducting a survey regarding their perceptions and experiences of unprofessional behavior.
Methods:
In October 2018, the authors evaluated the responses to a questionnaire administered to 548 emergency physicians at 28 university hospitals. The participants described their perceptions and experiences concerning 45 unprofessional behaviors classified into the following five categories: patient care, communication with colleagues, professionalism at work, research, and violent behavior and abusive language. Furthermore, the responses were analyzed by position (resident vs. faculty). Descriptive statistics were generated on the general characteristics of the study participants. To compare differences in responses by position and sex, the chi-square and Fisher exact tests were performed.
Results:
Of the 548 individuals invited to participate in this study, 253 responded (response rate, 46.2%). In 34 out of 45 questionnaires, more than half of participants reported having experienced unprofessional behavior despite their negative perceptions. Eleven perception questions and 38 experience questions for unprofessional behavior showed differences by position.
Conclusion
Most emergency physicians were well aware of what constituted unprofessional behavior; nevertheless, many had engaged in or observed such behavior.
4.A streamlined pipeline based on HmmUFOtu for microbial community profiling using 16S rRNA amplicon sequencing
Hyeonwoo KIM ; Jiwon KIM ; Ji Won CHOI ; Kwang-Sung AHN ; Dong-Il PARK ; Sangsoo KIM
Genomics & Informatics 2023;21(3):e40-
Microbial community profiling using 16S rRNA amplicon sequencing allows for taxonomic characterization of diverse microorganisms. While amplicon sequence variant (ASV) methods are increasingly favored for their fine-grained resolution of sequence variants, they often discard substantial portions of sequencing reads during quality control, particularly in datasets with large number samples. We present a streamlined pipeline that integrates FastP for read trimming, HmmUFOtu for operational taxonomic units (OTU) clustering, Vsearch for chimera checking, and Kraken2 for taxonomic assignment. To assess the pipeline’s performance, we reprocessed two published stool datasets of normal Korean populations: one with 890 and the other with 1,462 independent samples. In the first dataset, HmmUFOtu retained 93.2% of over 104 million read pairs after quality trimming, discarding chimeric or unclassifiable reads, while DADA2, a commonly used ASV method, retained only 44.6% of the reads. Nonetheless, both methods yielded qualitatively similar β-diversity plots. For the second dataset, HmmUFOtu retained 89.2% of read pairs, while DADA2 retained a mere 18.4% of the reads. HmmUFOtu, being a closed-reference clustering method, facilitates merging separately processed datasets, with shared OTUs between the two datasets exhibiting a correlation coefficient of 0.92 in total abundance (log scale). While the first two dimensions of the β-diversity plot exhibited a cohesive mixture of the two datasets, the third dimension revealed the presence of a batch effect. Our comparative evaluation of ASV and OTU methods within this streamlined pipeline provides valuable insights into their performance when processing large-scale microbial 16S rRNA amplicon sequencing data. The strengths of HmmUFOtu and its potential for dataset merging are highlighted.
5.The Impact of Persistent Low Weight Status on the Occurrence of Vertebral Fractures: A Nationwide PopulationBased Cohort Study
Sang-Min PARK ; Jiwon PARK ; Sangsoo HAN ; Hae-Dong JANG ; Jae-Young HONG ; Kyungdo HAN ; Ho-Joong KIM ; Jin S. YEOM
Journal of Korean Medical Science 2023;38(7):e48-
Background:
Although, being underweight is commonly associated with osteoporosis and sarcopenia, its association with vertebral fractures (VFs), is less well researched. We investigated the influence of cumulative, chronic periods of low weight and changes in body weight on VF development.
Methods:
We used a nationwide, population-based database with data on people (> 40 years) who attended three health screenings between January 1, 2007, and December 31, 2009 to assess the incidence of new VFs. Cox proportional hazard analyses were used to establish the hazard ratios (HRs) for new VFs based on the degree of body mass index (BMI), the cumulative numbers of underweight participants, and temporal change in weight.
Results:
Of the 561,779 individuals in this analysis, 5,354 (1.0%) people were diagnosed three times, 3,672 (0.7%) were diagnosed twice, and 6,929 (1.2%) were diagnosed once. The fully adjusted HR for VFs in underweight individuals was 1.213. Underweight individuals diagnosed only once, twice, or three times had an adjusted HR of 0.904, 1.443, and 1.256, respectively. Although the adjusted HR was higher in adults who were consistently underweight, there was no difference in those who experienced a temporal change in body weight. BMI, age, sex, and household income were significantly associated with VF incidence.
Conclusion
Low weight is a risk factor for VFs in the general population. Given the significant correlation between cumulative periods of low weight and the risk of VFs, it is necessary to treat underweight patients before a VF to prevent its development and other osteoporotic fractures.
6.Physical Properties of a New Type of Self-expandable Nitinol Stent.
SangSoo PARK ; Tae Hyung KIM ; Sang Woo SONG ; Seong Gwon KANG ; Soo Jin HUH ; Eun Sang KIM ; Cheol Saeng KIM ; Ho Young SONG
Journal of the Korean Radiological Society 1999;41(2):275-280
PURPOSE: To study the physical properties including hoop strength and flexibility of a newly developed nitinol stent. MATERIALS AND METHODS: The new stent was made of a single nitinol wire 0.15 -0 . 25 mm in diameter. This was wound around a cylindrical metallic jig with a constant angle to the longitudinal direction, and stents which varied with regard to wire thickness, number of wires at a lateral cut surface, and number of longitudinal windings were constructed. Hoop strength of the stents was measured with a spring gauge and compared with that of Wallstent and Hanaro stents. The flexibility of the new stent was evaluated on the basis of changes in s-tent diameter when bent in the direction of 180 degrees. RESULTS: Hoop strength of the new nitinol stent was proportional to 3.8(+/-0.3)-th power of the wire thickness. A greater number of wires on a lateral cut surface or a greater number of longitudinal windings also resulted in increased strength. However, the former caused an increase in total wire area and the latter resulted increased stent length when compressed. Hoop strength of the new nitinol stent was superior to that of Wallstent and Hanaro stents, and stent diameter did not decrease when the stent was bent in the direction of 180 degrees. CONCLUSIONS: Hoop strength of the new nitinol stent was most significantly affected by wire thickness. The s-tent was very flexible and thus seemed suitable for an angled lumen.
Pliability
;
Stents*
;
Wind
;
Wounds and Injuries
7.A New Liquid Embolic Agent(Embol) for Transcatheter Renal Artery Embolization: An Experimental Study in Rabbit.
Gyoo Sik JUNG ; Ji Ho KO ; Hyun Chul KIM ; Sang Hee LEE ; Kyung Seung OH ; Jin Do HUH ; Young Duk JOH ; Bang HUR ; Sangsoo PARK
Journal of the Korean Radiological Society 2002;46(1):17-24
PURPOSE: To evaluate the effectiveness and safety of a new liquid embolic agent in renal arterial embolization in the rabbit, and its clinical applicability. MATERIALS AND METHODS: A new embolic agent, Embol, was obtained by partial hydrolysis of polyvinyl acetate and dissolved in a mixture of 45% ethanol and 55% non-ionic contrast medium. Its radioopacity was therefore good. An average of 0.8 cc(0.5-0.9 cc) of Embol was used to embolize the renal artery of one kidney in 15 rabbits. The immediate effect of this was examined angiographically 5 minutes after the procedure. To permit histologic examination, five rabbits in each group were sacrificed 3 days (I), 2 weeks (II), and 4 weeks (III) after embolization: prior to embolization and prior to sacrifice, one rabbit in each group underwent renal scanning, and prior to sacrifice all underwent follow-up angiography. In three rabbits, blood urea nitrogen (BUN), creatinine, sodium(Na), and potassium(K) levels were measured before and 1, 3, 5, 7 and 14 days after embolization. RESULTS: Embol was easy to use and its radiopacity was good. Five minutes after embolization, angiography showed that total occlusion of the main renal or interlobar artery had been achieved in all rabbits. Serum BUN, creatinine, Na and K levels were within normal limits. Follow-up angiogram obtained in each group showed persistent occlusion of the renal artery in all but one rabbit in group I and one in group III. Renal scans revealed no evidence of radionuclide uptake in embolized kidneys, which were slightly enlarged in group I but became gradually smaller in groups II and III. In all animals, histologic examination showed diffuse coagulation necrosis of the embolized kidneys and in group III the cortex of these was extensively calcified. In group I the renal artery showed an apparently fresh occluding thrombosis, and in groups II and III a completely organized thrombosis was present. In group III this was calcified. CONCLUSION: Because of its good radioopacity, Embol is easy to controa, and is effective for renal artery embolization. As a permanent embolic agent, it appears suitable for clinical applications.
Angiography
;
Animals
;
Arteries
;
Blood Urea Nitrogen
;
Creatinine
;
Ethanol
;
Follow-Up Studies
;
Hydrolysis
;
Kidney
;
Necrosis
;
Polyvinyls
;
Rabbits
;
Renal Artery*
;
Thrombosis
8.Efficacy and Safety of Pancreatobiliary Endoscopic Procedures during Pregnancy.
Jae Joon LEE ; Sung Koo LEE ; Sang Hyung KIM ; Ga Hee KIM ; Do Hyun PARK ; Sangsoo LEE ; Dongwan SEO ; Myung Hwan KIM
Gut and Liver 2015;9(5):672-678
BACKGROUND/AIMS: Endoscopic therapy with endoscopic retrograde cholangiopancreatography (ERCP) has been suggested as an effective diagnostic and therapeutic tool for biliary and pancreatic disorders during pregnancy. In this report, we describe our experiences with pancreatobiliary endoscopic procedures during pregnancy. METHODS: We reviewed ERCP and endoscopic ultrasonography (EUS) procedures that were performed at a single tertiary care referral center between January 2002 and October 2013. Medical records were reviewed for the procedure indication, the duration of fluoroscopy, postprocedure complications, etc. Pregnancy outcomes and fetal complications were identified by chart review and phone calls to patients. RESULTS: A total of 10 ER-CPs and five EUSs were performed in 13 pregnant patients: four of whom underwent the procedure in the first trimester, eight in the second trimester, and one in the third trimester. Indications for endoscopic therapy included gallstone pancreatitis, obstructive jaundice with common bile duct (CBD) stone, asymptomatic CBD stone, pancreatic cyst, choledochal cyst, and acute cholecystitis. Only one patient had a complication, which was postprocedural hyperamylasemia. Two patients underwent an artificial abortion, one according to her own decision and the other due to an adverse drug reaction. CONCLUSIONS: ERCP seems to be effective and safe for pregnant women. Additionally, EUS can be an alternative to ERCP during pregnancy.
Adult
;
Biliary Tract Diseases/*surgery
;
Cholangiopancreatography, Endoscopic Retrograde/*adverse effects/methods
;
Endosonography/*adverse effects/methods
;
Female
;
Fetus
;
Humans
;
Obstetric Surgical Procedures/*adverse effects/methods
;
Pancreatic Diseases/*surgery
;
Pregnancy
;
Pregnancy Complications/*surgery
;
Pregnancy Outcome
;
Retrospective Studies
;
Young Adult
9.GTVseq: A Web-based Genotyping Tool for Viral Sequences.
Jae Min SHIN ; Ho Eun PARK ; Yong Ju AHN ; Doo Ho CHO ; Ji Han KIM ; Mee Kyung KEE ; Sung Soon KIM ; Joo Shil LEE ; Sangsoo KIM
Genomics & Informatics 2008;6(1):54-56
Genotyping Tool for Viral SEQuences (GTVseq) provides scientists with the genotype information on the viral genome sequences including HIV-1, HIV-2, HBV, HCV, HTLV-1, HTLV-2, poliovirus, enterovirus, flavivirus, Hantavirus, and rotavirus. GTVseq produces alternative and additive genotype information for the query viral sequences based on two different, but related, scoring methods. The genotype information produced is reported in a graphical manner for the reference genotype matches and each graphical output is linked to the detailed sequence alignments between the query and the matched reference sequences. GTVseq also reports the potential 'repeats' and/or 'recombination' sequence region in a separated window. GTVseq does not replace completely other well-known genotyping tools such as NCBI's virus sequence genotyping tool (http://www.ncbi. nlm.nih.gov/projects/genotyping/formpage.cgi), but provides additional information useful in the confirmation or for further investigation of the genotype(s) for the newly isolated viral sequences.
Enterovirus
;
Flavivirus
;
Genome, Viral
;
Genotype
;
Hantavirus
;
HIV-1
;
HIV-2
;
Human T-lymphotropic virus 1
;
Human T-lymphotropic virus 2
;
Poliovirus
;
Recombination, Genetic
;
Research Design
;
Rotavirus
;
Sequence Alignment
;
Viruses
10.GTVseq: A Web-based Genotyping Tool for Viral Sequences.
Jae Min SHIN ; Ho Eun PARK ; Yong Ju AHN ; Doo Ho CHO ; Ji Han KIM ; Mee Kyung KEE ; Sung Soon KIM ; Joo Shil LEE ; Sangsoo KIM
Genomics & Informatics 2008;6(1):54-56
Genotyping Tool for Viral SEQuences (GTVseq) provides scientists with the genotype information on the viral genome sequences including HIV-1, HIV-2, HBV, HCV, HTLV-1, HTLV-2, poliovirus, enterovirus, flavivirus, Hantavirus, and rotavirus. GTVseq produces alternative and additive genotype information for the query viral sequences based on two different, but related, scoring methods. The genotype information produced is reported in a graphical manner for the reference genotype matches and each graphical output is linked to the detailed sequence alignments between the query and the matched reference sequences. GTVseq also reports the potential 'repeats' and/or 'recombination' sequence region in a separated window. GTVseq does not replace completely other well-known genotyping tools such as NCBI's virus sequence genotyping tool (http://www.ncbi. nlm.nih.gov/projects/genotyping/formpage.cgi), but provides additional information useful in the confirmation or for further investigation of the genotype(s) for the newly isolated viral sequences.
Enterovirus
;
Flavivirus
;
Genome, Viral
;
Genotype
;
Hantavirus
;
HIV-1
;
HIV-2
;
Human T-lymphotropic virus 1
;
Human T-lymphotropic virus 2
;
Poliovirus
;
Recombination, Genetic
;
Research Design
;
Rotavirus
;
Sequence Alignment
;
Viruses