Purpose: To report a case of retrobulbar optic neuritis after COVID-19 infection.Case summary: A 20-year-old Korean man, without any previous relevant medical history, presented with sudden blurred vision in the left eye that began 6 days after a COVID-19 infection. At his initial visit, the best-corrected visual acuity in the left eye was counting fingers at 30 cm. The pupil showed a grade 2 relative afferent pupillary defect. The fundus exam was normal in both eyes. In the visual evoked potential (VEP) exam, the P100 amplitude of the left eye was decreased and delayed. Orbit magnetic resonance imaging showed asymmetric enlargement and mild enhancement in the left optic nerve. No other lesions were observed around the optic nerve. Steroid pulse therapy was started after a diagnosis of retrobulbar optic neuritis. After 1 month, the patient’s visual acuity had improved to 1.0 in the left eye. The relative afferent pupillary defect and visual field defect disappeared. On VEP, the P100 amplitude recovered, and the delay disappeared. Conclusions Retrobulbar optic neuritis is a possible neuro-ophthalmological complication of COVID-19 infection. In such cases, high-dose steroid pulse therapy may be helpful, as in the treatment of other forms of optic neuritis.

Purpose: To report a case of retrobulbar optic neuritis after COVID-19 infection.Case summary: A 20-year-old Korean man, without any previous relevant medical history, presented with sudden blurred vision in the left eye that began 6 days after a COVID-19 infection. At his initial visit, the best-corrected visual acuity in the left eye was counting fingers at 30 cm. The pupil showed a grade 2 relative afferent pupillary defect. The fundus exam was normal in both eyes. In the visual evoked potential (VEP) exam, the P100 amplitude of the left eye was decreased and delayed. Orbit magnetic resonance imaging showed asymmetric enlargement and mild enhancement in the left optic nerve. No other lesions were observed around the optic nerve. Steroid pulse therapy was started after a diagnosis of retrobulbar optic neuritis. After 1 month, the patient’s visual acuity had improved to 1.0 in the left eye. The relative afferent pupillary defect and visual field defect disappeared. On VEP, the P100 amplitude recovered, and the delay disappeared. Conclusions Retrobulbar optic neuritis is a possible neuro-ophthalmological complication of COVID-19 infection. In such cases, high-dose steroid pulse therapy may be helpful, as in the treatment of other forms of optic neuritis.

Purpose: To report a case of retrobulbar optic neuritis after COVID-19 infection.Case summary: A 20-year-old Korean man, without any previous relevant medical history, presented with sudden blurred vision in the left eye that began 6 days after a COVID-19 infection. At his initial visit, the best-corrected visual acuity in the left eye was counting fingers at 30 cm. The pupil showed a grade 2 relative afferent pupillary defect. The fundus exam was normal in both eyes. In the visual evoked potential (VEP) exam, the P100 amplitude of the left eye was decreased and delayed. Orbit magnetic resonance imaging showed asymmetric enlargement and mild enhancement in the left optic nerve. No other lesions were observed around the optic nerve. Steroid pulse therapy was started after a diagnosis of retrobulbar optic neuritis. After 1 month, the patient’s visual acuity had improved to 1.0 in the left eye. The relative afferent pupillary defect and visual field defect disappeared. On VEP, the P100 amplitude recovered, and the delay disappeared. Conclusions Retrobulbar optic neuritis is a possible neuro-ophthalmological complication of COVID-19 infection. In such cases, high-dose steroid pulse therapy may be helpful, as in the treatment of other forms of optic neuritis.

Purpose: To report a case of retrobulbar optic neuritis after COVID-19 infection.Case summary: A 20-year-old Korean man, without any previous relevant medical history, presented with sudden blurred vision in the left eye that began 6 days after a COVID-19 infection. At his initial visit, the best-corrected visual acuity in the left eye was counting fingers at 30 cm. The pupil showed a grade 2 relative afferent pupillary defect. The fundus exam was normal in both eyes. In the visual evoked potential (VEP) exam, the P100 amplitude of the left eye was decreased and delayed. Orbit magnetic resonance imaging showed asymmetric enlargement and mild enhancement in the left optic nerve. No other lesions were observed around the optic nerve. Steroid pulse therapy was started after a diagnosis of retrobulbar optic neuritis. After 1 month, the patient’s visual acuity had improved to 1.0 in the left eye. The relative afferent pupillary defect and visual field defect disappeared. On VEP, the P100 amplitude recovered, and the delay disappeared. Conclusions Retrobulbar optic neuritis is a possible neuro-ophthalmological complication of COVID-19 infection. In such cases, high-dose steroid pulse therapy may be helpful, as in the treatment of other forms of optic neuritis.

BACKGROUND: ABO antibody titration is useful for the evaluation of ABO-incompatible bone marrow or solid organ transplantations, yet the results quite vary between different test methods used. We compared the results of microcolumn agglutination and tube methods. METHODS: Anti-A and anti-B isoagglutionin titers were determined in 63 healthy individuals (23 O, 20 A, and 20 B blood groups) using 4 different methods: immediate spin tube (tube), microcolumn agglutination without anti-human globulin (AHG) (CAT), tube with AHG (tube-AHG) and microcolumn agglutination with AHG (CAT-AHG). RESULTS: The median (range) titers of anti-A and anti-B in group O individuals by tube, CAT, tube-AHG, and CAT-AHG methods were 64 (8-512), 64 (8-512), 128 (8-2,048), and 128 (16-2,048); 64 (16-128), 128 (16-256), 128 (16-512), and 256 (16-512), respectively. The median (range) titers of anti-A in group B and anti-B in group A individuals by the four methods were 64 (16-128), 128 (8-128), 128 (8-256), and 256 (8-256); 64 (8-128), 64 (8-128), 32 (8-128), and 64 (8-256), respectively. The isoagglutinin titer measured by CAT-AHGmethod was the highest. The titers measured by CAT and CAT-AHG methods were 0-1 titer higher than those by tube and tube-AHG methods, respectively. Whatever method was used, the isoagglutinin titers were higher in women than in men. CONCLUSIONS: CAT-AHG was the most sensitive method among the four methods tested. Since AHG titer values are critical for the clinical management and CAT has less manual procedures than tube method, CAT-AHG method could be used for the standardization of ABO antibody titration in different institutions.
Agglutination ; Animals ; Bone Marrow ; Cats ; Female ; Humans ; Organ Transplantation ; Transplants

BACKGROUND: The cis-AB is a very rare phenotype in the ABO blood group system. It corresponds to a special ABO allele that encodes glycosyltransferase that is capable of synthesizing both A and B antigens. Until now, the exon 6 and 7 gene sequences of cis-AB alleles are well known. In this study, we report on the intron 6 sequence structure of the cis-AB allele. METHODS: Standard serologic tests for the ABO blood group phenotypes were performed in four cis-AB samples. Allele-separation by cloning and subsequent sequencing was carried out. RESULTS: The results showed that intron 6 of cis-AB is almost identical to the A101 allele except for three single nucleotide polymorphisms at nucleotide positions 163, 179 and 662, where the nucleotides of the A101 replace those of B101. CONCLUSION: The intron 6 sequences of cis-AB in Koreans have both A101 and B101 blood group sequences.
ABO Blood-Group System ; Alleles ; Base Sequence ; Blood Grouping and Crossmatching ; Clone Cells ; Cloning, Organism ; Exons ; Introns ; Nucleotides ; Phenotype ; Polymorphism, Single Nucleotide ; Serologic Tests

STATEMENT OF PROBLEM: Titanium and its alloy, with their excellent bio-compatibility and above average resistance to corrosion, have been widely used in the field of dentistry. However, the excessive oxidization of titanium which occurs during the process of firing on porcelain makes the bonding of titanium and porcelain more difficult than that of the conventional metal-porcelain bonding. To solve this problem related to titanium-porcelain bonding, several methods which modify the surfaces, coat the surfaces of titanium with various pure metals and ceramics, to enable the porcelain adhesive by limiting the diffusion of oxygen and forming the adhesive oxides surfaces, have been investigated. PURPOSE: The purpose of this study was to know whether the titanium-porcelain bonding strength could be enhanced by treating the titanium surface with gold and TiN followed by fabrication of clinically applicable porcelain-fused-to-titanium crown. MATERIAL AND METHOD: The porcelain-fused-to-titanium crown was fabricated after sandblasting the surface of the casting titanium coping with Al2O3 and treating the surface with gold and TiN coating followed by condensation and firing of ultra-low fusing porcelain. To compare with porcelain-fused-to-titanium crowns, porcelain-fused-to-gold crowns were fabricated and used as control groups. The bonding strengths of porcelain-fused-to-gold crowns and porcelain-fused-totitanium crowns were set for comparison when the porcelain was fractured on purpose to get the experimental value of fracture strength. Then, the surface were examined by SEM and each fracturing pattern were compared with each other. RESULT: Those results are as follows. 1. The highest value of fracture strength of porcelain-fused-to-titanium crowns was in the order of group with gold coating, group with TiN coating, group with Al2O3 sandblasting. No statistically significant difference was found among the three (P>.05). 2. The porcelain-fused-to-gold crowns showed the highest value in bonding strength. The bonding strength of crowns porcelain-fused-to-titanium crowns of rest groups showed bonding strength reaching only 85%-94% of that of PFG, though simple comparision seemed unacceptable due to the difference in materials used. 3. The fracturing patterns between metal and porcelain showed mixed type of failure behavior including cohesive failure and adhesive failure as a similar patterns by examination with the naked eye and SEM. But porcelain-fused-to-gold crowns showed high incidence of adhesive failure and porcelain-fused-to-titanium crowns showed high incidence of cohesive failure. CONCLUSION: Above results proved that when fabricating porcelain-fused-to-titanium crowns, treating casting titanium surface with gold or TiN was able to enhance the bonding strength between titanium and porcelain. Mean value of masticatory force was found to showed clinically acceptable values in porcelain bonding strength in all three groups. However, more experimental studies and evaluations should be done in order to get better porcelain bonding strength and various surface coating methods that can be applied on titanium surface with ease.
Adhesives ; Alloys ; Bite Force ; Ceramics ; Corrosion ; Crowns* ; Dental Porcelain ; Dentistry ; Diffusion ; Fires ; Incidence ; Metals ; Oxides ; Oxygen ; Tin ; Titanium*

STATEMENT OF PROBLEM: Titanium has many advantages of high biocompatibility, physical properties, low-weight, low price and radiolucency, but it is incompatible with conventional dental porcelain due to titanium's oxidative nature. Many previous studies have shown that they used the method of sandblast for surface treatment prior to porcelain application, the researches are processing about the method of acid etching or surface coating. PURPOSE: The purpose of this research is to study the effect on bond strength of surface roughness between titanium and porcelain with the same surface topography. MATERIAL AND METHOD: In this study, we evaluated the bond strength by using 3-point bending test based on ISO 9693 after classified 8 groups - group P : polished with #1200 grit SiC paper, group S10 : 1.0 micrometer surface roughness with sandblasting, group S15 : 1.5 micrometer surface roughness with sandblasting, group S20 : 2.0 micrometer surface roughness with sandblasting, group S25 : 2.5 micrometer surface roughness with sandblasting, group S30 : 3.0 micrometer surface roughness with sandblasting, group S35 : 3.5 micrometer surface roughness with sandblasting, group E : 1.0 micrometer surface roughness with HCl etching. RESULTS: Within the confines of our research, the following results can be deduced. 1. In the results of 3-point bending test, the bond strength of sandblasting group showed significant differences from one of polishing group, acid etching group(P<.05). 2. The bond strength of sandblasting groups did not show significant differences. 3. After surface treatments, the group treated with sandblasting showed irregular aspect formed many undercuts, in the SEM photographs. The bond strength of sandblasting group was higher than 25 MPa, the requirement of ISO 9693. CONCLUSION: In above results, bond strength of titanium and low-fusing porcelain is influenced more to surface aspect than surface roughness. And titanium has clinically acceptable bond strength below surface roughness of 3.5 micrometer.
Dental Porcelain ; Titanium

STATEMENT OF PROBLEM: Titanium is well known as a proper metal for the dental restorations, because it has an excellent biocompatibility, resistance to corrosion, and mechanical property. However, adhesion between titanium and dental porcelains is related to the diffusion of oxygen to the reaction layers formed on cast-titanium surfaces during porcelain firing and those oxidized layers make the adhesion difficult to be formed. Many studies using mechanical, chemical and physical methods to enhance the titanium-ceramic adhesion have been actively performed. PURPOSE: This study meant to comparatively analyse the adhesion characteristics depending on different titanium surface coatings after coating the casts and wrought titanium surfaces with Au and TiN. MATERIAL AND METHOD: In this study, the titanium specimens (CP-Ti, Grade 2, Kobe still Co. Japan) were categorized into cast and wrought titanium. The wrought titanium was cast by using the MgO-based investment(Selevest CB, Selec). The cast and wrought titanium were treated with Au coating(ParaOne(R), Gold Ion Sputter, Model PS-1200) and TiN coating(ATEC system, Korea) and the ultra low fusing dental porcelain was fused and fired onto the samples. Biaxial flection test was done on the fired samples and the porcelain was separated. The adhesion characteristics of porcelain and titanium after firing and the specimen surfaces before and after the porcelain fracture test were observed with SEM. The atomic percent of Si on all sample surfaces was comparatively analysed by EDS. In addition, the constituents of specimen surface layers after the porcelain fracture and the formed compound were evaluated by X-ray diffraction diagnosis. RESULT: The results of this study were obtained as follows : 1. The surface characteristics of cast and wrought titanium after surface treatment(Au, TiN, Al2O3 sandblasting) were similar and each cast and wrought titanium showed similar bonding characteristics. 2. Before and after the biaxial flection test, the highest atomic weight change of Si component was found in Al2O3 sandblasted wrought titanium(28.6at.% --> 8.3at.%). On the other hand, the least change was seen in Au-Pd-In alloy(24.5at.%--> 19.1at.%). 3. Much amount of Si components was uniformly distributed in Au and TiN coated titanium, but less amount of Si's was unevenly dispersed on Al2O3 sandblasting surfaces. 4. In X-ray diffraction diagnosis after porcelain debonding, we could see Au2Ti compound and TiN coating layers on Au and TiN coated surfaces and TiO2, typical oxide of titanium, on all titanium surfaces. 5. Debonding of porcelain on cast and wrought titanium surface after the biaxial flection is considered as a result of adhesion deterioration between coating layers and titanium surfaces. We found that there are both adhesive failure and cohesive failure at the same time. CONCLUSION: These results showed that the titanium-ceramic adhesion could be improved by coating cast and wrought titanium surfaces with Au and TiN when making porcelain fused to metal crowns. In order to use porcelain fused to titanium clinically, it is considered that coating technique to enhance the bonding strength between coating kKlayers and titanium surfaces should be developed first.
Adhesives ; Corrosion ; Crowns ; Dental Porcelain* ; Diagnosis ; Diffusion ; Fires ; Hand ; Oxygen ; Tin ; Titanium* ; X-Ray Diffraction

BACKGROUND: There have been several studies showing that angiotensin II and the angiotensin convertingenzyme (ACE) contribute to the activation of fibroblast including the pulmonary fibrosis, and apoptosis of the al veolar epithelium in idiopathic intersititial pneumonia. This study was performed to identify the relationship between the serum angiotensin II. ACE and the pulmonary function test (PFT), the dyspnea score, and the cell fraction of the bronchoalveolar lavage fluid (BALF). METHODS: Twenty three patients with idiopathic interstitial pneumonia from March, 1999 to October, 2001 at Gachon medical school were enrolled in this study. They were divided into IPF(UIP) (16) and NSIP (7) group. Twelve of the idiopathic interstitial pneumonia patients (UIP : 5, NSIP: 7) were diagnosed by an open lung biopsy, 11 of IPF patients were diagnosed by the American Thoracic Society (ATS) diagnostic criteria. The PFT values, dyspnea score, serum ACE and angiotensin II were measured, and a bronchoscopy was performed to obtain the BALF. RESULTS: Of all the patients, 7 were in the normal range and 14 showed an increase in the serum level of angiotensin II. In terms of the serum ACE level, 14 patients had an increased level. The DLCO% of the angiotensin II. increased group was significantly lower than the not-increased group (p=0.021). Other factors did not correlate with the serum ACE or the angiotensin II increased group and not-increased group. CONCLUSION: These results suggest that an increased angiotensinII serum level may be associated with in crease in the of alveolar capillary block in the progression of pulmonary fibrosis in idiopathic interstitial pneumonia.
Angiotensin II* ; Angiotensins* ; Apoptosis ; Biomarkers* ; Biopsy ; Bronchoalveolar Lavage Fluid ; Bronchoscopy ; Capillaries ; Dyspnea ; Epithelium ; Fibroblasts ; Fibrosis ; Humans ; Idiopathic Interstitial Pneumonias* ; Lung ; Peptidyl-Dipeptidase A* ; Pneumonia ; Pulmonary Fibrosis ; Reference Values ; Respiratory Function Tests ; Schools, Medical