1.Fit of fixture/abutment/screw interfaces of internal connection implant system.
Jin Sup KIM ; Hee Jung KIM ; Chae Heon CHUNG ; Dae Hwa BAEK
The Journal of Korean Academy of Prosthodontics 2005;43(3):338-351
STATEMENT OF PROBLEM: Accurate fit between the implant components is important because the misfit of the implant components results in frequent screw loosening, irreversible screw fracture, plaque accumulation, poor soft tissue reaction, and destruction of osseointegration. PURPOSE: This study is to evaluate the machining accuracy and consistency of the implant fixture/abutment/screw interfaces of the internal connection system by using a Stereoscopic Zoom microscope and FE-SEM(field emission scanning electron microscope) MATERIALS AND METHODS: The implant systems selected in this study were internal connection type implants from AVANA(Osstem(R)), Bioplant(Cowell-Medi(R)), Dio(DIO(R)), Neoplant(Neobiotech (R)), Implantium(Dentium(R))systems. Each group was acquired 2 fixtures at random. Two piece type abutment and one piece type abutment for use with each implant system were acquired. Screw were respectively used to hold a two piece type abutment to a implant fixture. The implant fixtures were perpendiculary mounted in acrylic resin block. Each two piece abutment was secured to the implant fixture by screw and one piece abutment also secured to the implant fixture. Abutment/fixture assembly were mounted in liquid unsaturated polyester. All samples were cross-sectioned with grinder-polisher unit. Finally all specimens were analysed the fit between implant fixture/abutment/screw interfaces Results and CONCLUSIONS: 1. Implant fixture/abutment/screw connection interfaces of internal connection systems made in Korea were in good condition. 2. The results of the above study showed that materials and mechanical properties and quality of milling differed depending on their manufacturing companies.
Korea
;
Osseointegration
;
Polyesters
2.Protection Against Respiratory Syncytial Virus Infection Induced Airway Hyperresponsiveness by DNA Encoding RSV-G Protein Immunization.
Jae Youn CHO ; Dae Hyun LIM ; Kwang Je BAEK ; Kwang Ho IN ; Se Hwa YOO ; David H BROIDE
Pediatric Allergy and Respiratory Disease 2001;11(2):80-92
PURPOSE: Respiratory syncytial virus is the primary cause of pneumonia and bronchiloitis in young children and infants. RSV infection is also known to be very important to asthma patient, because previous RSV infection increases the frequency of the asthma development and RSV infection may cause airway hyperresponsiveness. Natural RSV infection does not provide complete immunity and reinfection occurs throughout life. Several strategies have recently been used in RSV vaccine development, including the generation of formalin inactivated RSV(FI-RSV), peptides, recombinant vaccine viruses (rVV), and DNA based vaccines. Previous studies in mice primed with RSV G protein enhanced lung pathology resulted from a Th2 host immune response against the viral G protein. We studied for the evaluation of protective immunity, effect on airway hyperesponsiveness, and influence on lung pathology after pND G immunization. METHODS: BALB/c mice were injected with pND G(50g in 1 g/l PBS), pND G-HA (50 g), pND(50 g) FI-RSV(10 6PFU) i.d.at 0, 2, 4 weeks. Four weeks later, mice were challenged with RSV(10 6PFU). Mice were sacrificed on postchallenge day 4 and their lungs were removed for RT-PCR and viral titration. The other mice were sacrificed on postchallenge day 6 for bronchoalveolar lavage, serum and histologic examination. Airway responsiveness was assessed by using a single chamber whole body plethysmography on post challenge day 5. RESULTS: 1) Vaccination with pND-G reduced the Mch(methacholine) induced airway hyperresponsiveness after RSV infection(P<0.05). 2) Viral titers are decreased in pND-G group and FI-RSV group(P<0.05) and complete protection from RSV infection was 9/12(75%) in pND-G group. 3) Serum anti-G IgG antibody is more increased in pND-G group than RSV group(P<0.05). 4) IFN-/IL-5 ratio is increased in pND-G group(0.59) and decreased in FI-RSV group(P<0.036). 5) Inflammatory response in BAL after RSV infection was decreased by pND-G vaccination(P>0.05). CONCLUSION: In this study, immunization with pND encoding G protein induced decrease in airway hyperresponsiveness, and protection against RSV infection of the lower respiratory tract infection and also induced virus neutralizing antibody and decrease in lymphocytic inflammation. pND G immunization elicited balanced pulmonary Th1/Th2 cytokine response without atypical pulmonary inflammatory responses.
Animals
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Antibodies, Neutralizing
;
Asthma
;
Bronchoalveolar Lavage
;
Child
;
DNA*
;
Formaldehyde
;
GTP-Binding Proteins
;
Humans
;
Immunization*
;
Immunoglobulin G
;
Infant
;
Inflammation
;
Lung
;
Mice
;
Pathology
;
Peptides
;
Plethysmography, Whole Body
;
Pneumonia
;
Respiratory Syncytial Viruses*
;
Respiratory Tract Infections
;
Vaccination
;
Vaccines
3.Three Cases of Multiple Primary Cancer in Esophagus and Stomach.
Hye Jeong YOON ; Hyo Jong BAEK ; Sang Moon LEE ; Choong Ki LEE ; Hwa Ryoung SEO ; Dae Hyun KIM ; Dong Hwan LEE ; Hak Keun KIM
Korean Journal of Gastrointestinal Endoscopy 1996;16(3):459-467
Multiple primary cancer is defined as the case of primary malignant tumors of different histologic origins each other in one person, The incidence of multiple primary cancer has been increasing recently due to more developed diagnostie procedure and long survival of cancer patients. In esophageal cancer patients, comibined prevalence of other malignancy is rela tively high. We have experienced three cases of gastric adenocarcinoma with esophageal squamous cell carcinoma and report these cases with a review of literatures.
Adenocarcinoma
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Carcinoma, Squamous Cell
;
Esophageal Neoplasms
;
Esophagus*
;
Humans
;
Incidence
;
Prevalence
;
Stomach*
4.Nontraumatic Intracystic Hemorrhage of Arachnoid Cyst: CT and MR Findings.
Seung Jin KIM ; Hye Jin BAEK ; Jin Il MOON ; Soo Buem CHO ; Bo Hwa CHOI ; Kyungsoo BAE ; Kyung Nyeo JEON ; Dae Seob CHOI
Investigative Magnetic Resonance Imaging 2016;20(2):120-122
Arachnoid cysts (AC) are intraarachnoidal cerebrospinal fluid collections, and account for 1% of all intracranial space-occupying lesions. Intracystic hemorrhage of the AC can occur spontaneously, but this is an extremely rare event. Herein, we present a case of hemorrhagic AC in a nontraumatic patient in the left middle cranial fossa. We also performed relevant literature review on this disease.
Arachnoid Cysts
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Arachnoid*
;
Cerebrospinal Fluid
;
Cranial Fossa, Middle
;
Hemorrhage*
;
Humans
;
Magnetic Resonance Imaging
;
Rupture
5.Susceptibility Vessel Sign for the Detection of Hyperacute MCA Occlusion: Evaluation with Susceptibility-weighted MR Imaging.
Sangmin LEE ; Soo Bueum CHO ; Dae Seob CHOI ; Sung Eun PARK ; Hwa Seon SHIN ; Hye Jin BAEK ; Ho Cheol CHOI ; Ji Eun KIM ; Hye Young CHOI ; Mi Jung PARK
Investigative Magnetic Resonance Imaging 2016;20(2):105-113
PURPOSE: Susceptibility vessel sign (SVS) on gradient echo image, which is caused by MR signal loss due to arterial thrombosis, has been reported in acute middle cerebral artery (MCA) infarction. However, the reported sensitivity and diagnostic accuracy of SVS have been variable. Susceptibility-weighted imaging (SWI) is a newly developed MR sequence. Recent studies have found that SWI may be useful in the field of cerebrovascular diseases, especially for detecting the presence of prominent veins, microbleeds and the SVS. The purpose of this study was to evaluate the diagnostic values of SWI for the detection of hyperacute MCA occlusion. MATERIALS AND METHODS: Sixty-nine patients (37 males, 32 females; 46-89 years old [mean, 69.1]) with acute stroke involving the MCA territory underwent MR imaging within 6 hours after the symptom onset. MR examination included T2, FLAIR (fluid-attenuated inversion recovery), DWI, SWI, PWI (perfusion-weighted imaging), contrast-enhanced MR angiography (MRA) and contrast-enhanced T1. Of these patients, 28 patients also underwent digital subtraction angiography (DSA) within 2 hours after MR examination. Presence or absence of SVS on SWI was assessed without knowledge of clinical, DSA and other MR imaging findings. RESULTS: On MRA or DSA, 34 patients (49.3%) showed MCA occlusion. Of these patients, SVS was detected in 30 (88.2%) on SWI. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of SWI were 88.2%, 97.1%, 96.8%, 89.5% and 92.8%, respectively. CONCLUSION: SWI was sensitive, specific and accurate for the detection of hyperacute MCA occlusion.
Angiography
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Angiography, Digital Subtraction
;
Cerebrovascular Disorders
;
Female
;
Humans
;
Infarction
;
Magnetic Resonance Imaging*
;
Male
;
Middle Cerebral Artery
;
Sensitivity and Specificity
;
Stroke
;
Thrombosis
;
Veins
6.Splenial Lesions of the Corpus Callosum: Disease Spectrum and MRI Findings.
Sung Eun PARK ; Dae Seob CHOI ; Hwa Seon SHIN ; Hye Jin BAEK ; Ho Cheol CHOI ; Ji Eun KIM ; Hye Young CHOI ; Mi Jung PARK
Korean Journal of Radiology 2017;18(4):710-721
The corpus callosum (CC) is the largest white matter structure in the brain, consisting of more than 200–250 million axons that provide a large connection mainly between homologous cerebral cortical areas in mirror image sites. The posterior end of the CC is the thickest part, which is called the splenium. Various diseases including congenital to acquired lesions including congenital anomalies, traumatic lesions, ischemic diseases, tumors, metabolic, toxic, degenerative, and demyelinating diseases, can involve the splenium of the CC and their clinical symptoms and signs are also variable. Therefore, knowledge of the disease entities and the imaging findings of lesions involving the splenium is valuable in clinical practice. MR imaging is useful for the detection and differential diagnosis of splenial lesions of the CC. In this study, we classify the disease entities and describe imaging findings of lesions involving the splenium of the CC based on our experiences and a review of the literature.
Axons
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Brain
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Corpus Callosum*
;
Demyelinating Diseases
;
Diagnosis, Differential
;
Magnetic Resonance Imaging*
;
White Matter
7.MR Findings of Seizure-Related Cerebral Cortical Lesions during Periictal Period.
Na Yoon KIM ; Hye Jin BAEK ; Dae Seob CHOI ; Jee Young HA ; Hwa Seon SHIN ; Ju Ho KIM ; Ho Cheol CHOI ; Ji Eun KIM ; Mi Jung PARK
Investigative Magnetic Resonance Imaging 2017;21(2):82-90
PURPOSE: This study investigated the MRI, MR angiography (MRA) and MR perfusion findings of seizure-related cerebral cortical lesions during the periictal period. MATERIALS AND METHODS: From a retrospective review of the institutional database between 2011 and 2014, a total of 21 patients were included in this study. Two radiologists assessed periictal MRI, including MRA and MR perfusion, in patients with seizure-related cortical lesions. The parameters examined include: location of cortical abnormality, multiplicity of the affected cortical region, cerebral vascular dilatation, perfusion abnormality and other parenchymal lesions. RESULTS: All patients showed T2 hyperintense cerebral cortical lesions with accompanying diffusion restriction, either unilateral (18/21, 85.7%) or bilateral (3/21, 14.3%). Of the 21 patients enrolled, 10 (47.6%) had concurrent T2 hyperintense thalamic lesions, and 10 (47.6%) showed hippocampal involvement. Of the 17 patients (81%) who underwent MRA, 13 (76.5%) showed vascular dilatation with increased flow signal in the cerebral arteries of the affected cortical regions. On MR perfusion, all 5 patients showed cortical hyperperfusion, corresponding to the region of cortical abnormalities. CONCLUSION: Seizure-related cerebral cortical lesions are characterized by T2 and diffusion hyperintensities, with corresponding cerebral hyperperfusion and vascular dilatation. These findings can be helpful for making an accurate diagnosis in patients with seizure.
Angiography
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Cerebral Arteries
;
Diagnosis
;
Diffusion
;
Dilatation
;
Humans
;
Magnetic Resonance Angiography
;
Magnetic Resonance Imaging
;
Perfusion
;
Retrospective Studies
;
Seizures
8.MR Findings of Seizure-Related Cerebral Cortical Lesions during Periictal Period.
Na Yoon KIM ; Hye Jin BAEK ; Dae Seob CHOI ; Jee Young HA ; Hwa Seon SHIN ; Ju Ho KIM ; Ho Cheol CHOI ; Ji Eun KIM ; Mi Jung PARK
Investigative Magnetic Resonance Imaging 2017;21(2):82-90
PURPOSE: This study investigated the MRI, MR angiography (MRA) and MR perfusion findings of seizure-related cerebral cortical lesions during the periictal period. MATERIALS AND METHODS: From a retrospective review of the institutional database between 2011 and 2014, a total of 21 patients were included in this study. Two radiologists assessed periictal MRI, including MRA and MR perfusion, in patients with seizure-related cortical lesions. The parameters examined include: location of cortical abnormality, multiplicity of the affected cortical region, cerebral vascular dilatation, perfusion abnormality and other parenchymal lesions. RESULTS: All patients showed T2 hyperintense cerebral cortical lesions with accompanying diffusion restriction, either unilateral (18/21, 85.7%) or bilateral (3/21, 14.3%). Of the 21 patients enrolled, 10 (47.6%) had concurrent T2 hyperintense thalamic lesions, and 10 (47.6%) showed hippocampal involvement. Of the 17 patients (81%) who underwent MRA, 13 (76.5%) showed vascular dilatation with increased flow signal in the cerebral arteries of the affected cortical regions. On MR perfusion, all 5 patients showed cortical hyperperfusion, corresponding to the region of cortical abnormalities. CONCLUSION: Seizure-related cerebral cortical lesions are characterized by T2 and diffusion hyperintensities, with corresponding cerebral hyperperfusion and vascular dilatation. These findings can be helpful for making an accurate diagnosis in patients with seizure.
Angiography
;
Cerebral Arteries
;
Diagnosis
;
Diffusion
;
Dilatation
;
Humans
;
Magnetic Resonance Angiography
;
Magnetic Resonance Imaging
;
Perfusion
;
Retrospective Studies
;
Seizures
9.Perfusion Hyperintensities in Patients With Seizures: Evaluation With Arterial Spin Labeling Magnetic Resonance Imaging Within 24 Hours After Onset
Dong Hyun KOH ; Hyeong Gi CHOI ; Dae Seob CHOI ; Hwa Seon SHIN ; Hye Jin BAEK ; Young Soo KIM ; Eun Ha KOH
Investigative Magnetic Resonance Imaging 2024;28(1):18-26
Purpose:
We used arterial spin labeling (ASL) perfusion magnetic resonance (MR) imaging to evaluate cerebral perfusion abnormalities in patients with seizures within 24 hours of symptom onset.
Materials and Methods:
A retrospective search of our institutional database identified 27 patients who had undergone ASL perfusion studies for seizures or seizure-like symptoms.The inclusion criteria were as follows: 1) history of seizure, 2) MR examination performed within 24 hour of seizure onset, and 3) localized perfusion abnormality on ASL. We evaluated the presence, location, and extent of perfusion abnormalities on ASL and signal abnormalities on fluid-attenuated inversion recovery (FLAIR), diffusion-weighted image (DWI), and susceptibility-weighted image (SWI), respectively. All pathological MR findings, accompanying focal neurological symptoms, and electroencephalogram (EEG) findings were compared.
Results:
The mean time from symptom onset to MR examination was 5 h 54 min. All patients (n = 27) showed localized increased perfusion on ASL perfusion imaging. On FLAIR imaging, 20 patients (74.1%) showed hyperintensity in the area of perfusion abnormality.In 19 patients (70.4%), DWI showed hyperintensity of the lesion with decreased apparent diffusion coefficient value (ADC). Seven patients (25.9%) showed a focal parenchymal area of pseudo-narrowed cortical veins on SWI, associated with focal hyperperfusion. In 20 patients (74.1%), the extent of perfusion abnormalities on ASL was greater than that of signal abnormalities on FLAIR or DWI. In 14/16 patients (87.5%) with abnormal EEG findings, the area with EEG findings and the location of the hyperperfusion abnormality on ASL corresponded.
Conclusion
In patients with seizures within 24 hours of symptom onset, ASL perfusion imaging revealed localized hyperperfusion, which was more frequent than signal intensity abnormalities on FLAIR or DWI. The locations of hyperperfusion areas correlated with EEG abnormalities. Thus, the ASL sequence may be a useful clinical assessment protocol for evaluating patients with seizures.
10.Impact of Wildfire Smoke Exposure on Health in Korea
Kihyun LEE ; Sung-Soo OH ; Kyoung Sook JEONG ; Yeon-Soon AHN ; Sei Jin CHANG ; Se Hwa HONG ; Dae Ryong KANG ; Sung-Kyung KIM ; Sang-Baek KOH
Yonsei Medical Journal 2022;63(8):774-782
Purpose:
The characteristic topography and climate often affect the occurrence of large-scale wildfires in the Eastern Gangwon-do region of Korea. However, there are no studies on the health effects of these wildfires in Korea. This study aimed to analyze the differences in medical use between a wildfire-affected area and an adjacent non-affected area before and after a wildfire in 2019 in Gangwon-do, Korea.
Materials and Methods:
We used medical usage data from the Korean National Health Insurance Corporation. Rates of medical use were determined for citizens of a wildfire-affected area in the Eastern Yeongdong region and a non-affected area in the Western Yeongseo region. Logistic regression analysis was performed considering an increase in medical use per individual as a dependent variable; age, sex, income, smoking, drinking, and exercise were included as confounding variables.
Results:
The odds ratio for medical use in Yeongdong region increased significantly after 3 days, 3 months, and 1 year after a fire occurred, compared with Yeongseo region.
Conclusion
The results of this study confirmed that the use of medical care increased for residents of a wildfire-affected area, compared with those of an adjacent non-affected area. This is the first study on the relationship between wildfires and inpatient medical use in Korea.