Coronavirus disease 2019 (COVID-19) vaccination may non-specifically alter the host immune system. This study aimed to evaluate the effect of COVID-19 vaccination on hepatitis B surface Ag (HBsAg) titer and host immunity in chronic hepatitis B (CHB) patients. Consecutive 2,797 CHB patients who had serial HBsAg measurements during antiviral treatment were included in this study. Changes in the HBsAg levels after COVID-19 vaccination were analyzed. The dynamics of NK cells following COVID-19 vaccination were also examined using serial blood samples collected prospectively from 25 healthy volunteers. Vaccinated CHB patients (n=2,329) had significantly lower HBsAg levels 1–30 days post-vaccination compared to baseline (median, −21.4 IU/ml from baseline), but the levels reverted to baseline by 91–180 days (median, −3.8 IU/ml). The velocity of the HBsAg decline was transiently accelerated within 30 days after vaccination (median velocity: −0.06, −0.39, and −0.04 log 10 IU/ml/year in pre-vaccination period, days 1–30, and days 31–90, respectively). In contrast, unvaccinated patients (n=468) had no change in HBsAg levels. Flow cytometric analysis showed that the frequency of NK cells expressing NKG2A, an NK inhibitory receptor, significantly decreased within 7 days after the first dose of COVID-19 vaccine (median, −13.1% from baseline; p<0.001). The decrease in the frequency of NKG2A + NK cells was observed in the CD56dimCD16+ NK cell population regardless of type of COVID-19 vaccine. COVID-19 vaccination leads to a rapid, transient decline in HBsAg titer and a decrease in the frequency of NKG2A + NK cells.

The aim of this study was to analyze cells from human dental pulp tissue of impacted supernumerary teeth as stem cells with flow cytometry. Human dental pulp cells from 15 supernumerary teeth were identified their characteristics as stem cells by expression of mesenchymal stem cell markers through flow cytometry analysis at passage 3 and passage 10. Cluster of differentiation (CD) 73, CD 90, CD 34, CD 45 and STRO-1 cell surface markers were used to figure out characteristics of dental pulp stem cells from supernumerary teeth. At passage 3, the cell population showed positive expression of CD 73, CD90 and STRO-1, lacked expression of CD 34 and CD 45. At passage 10, CD 73, CD 90 and STRO-1 showed positive expression while CD 34 and CD 45 showed negative expression. This study indicated that dental pulp stem cells of supernumerary teeth had the properties of mesenchymal stem cells at both early and late passage. Impacted supernumerary teeth could be considered as a noble source of stem cells because of rapid growth and maintaining characteristics of stem cells until late passage.
Dental Pulp ; Flow Cytometry ; Humans ; Mesenchymal Stromal Cells ; Stem Cells ; Tooth, Supernumerary

PURPOSE: The purpose of this study is to investigate the correlations of various kinetic parameters derived from the time intensity curve in a xenograft mouse model injected with a prostate cancer model (PC-3 and LNCaP) using an ultrasound contrast agent with histopathologic parameters. MATERIALS AND METHODS: Twenty nude mice were injected with human prostate cancer cells (15 PC-3 and five LNCaP) on their hind limbs. A bolus of 500 microL (1 x 10(8) microbubbles) of second-generation US contrast agent (SonoVue) was injected into the retroorbital vein. The region of interest was drawn over the entire tumor. The time intensity curve was acquired and then fitted to a gamma variate function. The maximal intensity (A), time to peak (Tp), maximal wash-in rate (washin), washout rate (washout), area under the curve up to 50 sec (AUC50), area under the ascending slope (AUC(in)), and area under the descending slope (AUC(out)) were derived from the parameters of the gamma variate fit. Immunohistochemical staining for VEGF and CD31 was performed. Tumor volume, the area percentage of VEGF stained in a field, and the count of CD31 (microvessel density, MVD) positive vessels showed correlation with the parameters from the time intensity curve. RESULTS: No significant differences were observed between the kinetic and histopathological parameters from each group. MVD showed positive correlation with A (r=0.625, p=0.003), washin (r=0.462, p=0.040), AUC50 (r=0.604, p=0.005), and AUC(out) (r=0.587, p=0.007). Positive correlations were also observed between tumor volume and AUC50 (r=0.481, p=0.032), washin (r=0.662, p=0.001), and AUC(out) (r=0.547, p=0.012). Washout showed negative correlations with MVD (r=-0.454, p=0.044) and tumor volume (r=-0.464, p=0.039). The area percentage of VEGF did not show any correlation with calculated data from the curve. CONCLUSION: MVD showed correlations with several of the kinetic parameters. CE-US has the potential for prediction of tumor vascularity in a prostate cancer animal model.
Animals ; Extremities ; Humans ; Mice ; Mice, Nude ; Models, Animal ; Prostate ; Prostatic Neoplasms ; Transplantation, Heterologous ; Tumor Burden ; Vascular Endothelial Growth Factor A ; Veins

Enteropathy-associated T-cell lymphoma (EATL) is an unusual primary gastrointestinal lymphoma, and it is particularly associated with celiac sprue. These patients typically suffer from abdominal pain, diarrhea and/or weight loss. Primary intestinal T-cell lymphoma without celiac sprue is known to be rare. We report here on a case of EATL that presented with persistent abdominal pain and diarrhea, but this patient was without celiac sprue.
Abdominal Pain* ; Celiac Disease ; Diarrhea* ; Enteropathy-Associated T-Cell Lymphoma ; Humans ; Intestines ; Lymphoma ; Lymphoma, T-Cell* ; T-Lymphocytes* ; Weight Loss

Enteropathy-associated T-cell lymphoma (EATL) is an unusual primary gastrointestinal lymphoma, and it is particularly associated with celiac sprue. These patients typically suffer from abdominal pain, diarrhea and/or weight loss. Primary intestinal T-cell lymphoma without celiac sprue is known to be rare. We report here on a case of EATL that presented with persistent abdominal pain and diarrhea, but this patient was without celiac sprue.
Abdominal Pain* ; Celiac Disease ; Diarrhea* ; Enteropathy-Associated T-Cell Lymphoma ; Humans ; Intestines ; Lymphoma ; Lymphoma, T-Cell* ; T-Lymphocytes* ; Weight Loss

BACKGROUND/AIMS: Internet has become an important source of medical information not only for medical personnels but also for patients. The aim of this study was to evaluate the quality of internet based medical information about 'gastroesophageal reflux' or 'reflux esophagitis' in Korea. METHODS: The first 15 internet sites using the key words 'gastroesophageal reflux' or 'reflux esophagitis' were retrieved from the 7 most frequently used internet search engines. The quality of information from a total of 108 websites was evaluated using a checklist. RESULTS: Among total 108 sites related to 'gastroesophageal reflux' or 'reflux esophagitis', fifty-six sites (51.8%) were made by hospitals or clinics and 94 sites (87.0%) were made for patients. Of the 108 sites, eleven web sites (10.1%) had more than three JAMA benchmarks (authorship, references, currency, and disclosure). Higher quality sites (at least three JAMA benchmarks) were less likely to contain inaccurate information than lower quality sites (fewer than three JAMA benchmarks)-3/11 (27.2%) vs. 60/97 (61.9%) (p<0.01). Despite the fact that articles in the literature emphasized an insufficient evidence to support an association between the lifestyle, dietary behaviors, and GERD, such guidelines continue to be recommended as first-line therapy in most websites. CONCLUSIONS: Informations about gastroesophageal reflux disease were incomplete in the majority of medical web sites. These would bring about confusion to patients seeking for an information about GERD through the internet. There is a need for better sources in evidence based informations about gastroesophaeal reflux diseases on the web.
Gastroesophageal Reflux/diagnosis/drug therapy/*etiology ; Health Education/*standards ; Humans ; Information Services/standards ; *Internet ; Korea ; Quality of Health Care ; User-Computer Interface

BACKGROUND: With the progress of limited surgery and endoscopic treatment for early gastric cancer (EGC), multiple synchronous EGCs, a cause of recurrence, become more important. The objective of this study was to elucidate the characteristics of multiple synchronous EGCs with an emphasis on features of preoperatively undiagnosed lesions. METHODS: We retrospectively reviewed medical records of 496 patients who underwent a gastrectomy for EGC at our institution between January 2004 and December 2004. RESULTS: Twenty-four patients (4.8%) had multiple synchronous EGCs with 24 main and 27 accessory lesions. Multiple synchronous EGCs showed male predominance (p=0.03). Other characteristics including lymph node metastasis were the same as with single EGC. Out of 27 accessory lesions, six lesions (22%) were not detected preoperatively in six patients (25%). Macroscopically five lesions were flat and one lesion was depressed. Five lesions were located at the anterior or posterior wall of the middle and low third portion and one lesion was located at the lesser curvature side of the upper third portion of the stomach. Two lesions were 4 mm, one lesion was 8 mm, two lesions were 12 mm and one lesion was 15 mm in size (mean diameter = 9.1 mm). Histologically, four lesions were of the differentiated type and two lesions were of the undifferentiated type. CONCLUSIONS: Multiple synchronous EGCs have same clinicopathologic features as a single EGC except for male predominance. Considering the possibility of a synchronous lesion, one should examine the entire stomach precisely with special attention to the anterior, posterior wall and lesser curvature side of the same or neighboring area of a known EGC lesion before treatment.
Gastrectomy ; Humans ; Lymph Nodes ; Male ; Medical Records ; Neoplasm Metastasis ; Recurrence ; Retrospective Studies ; Stomach ; Stomach Neoplasms*

Small cell lung cancer (SCLC) is one of the most fatal cancers in humans and many factors are known to be related to its poor prognosis. Immunohistochemical (IHC) stainings were done on SCLC specimens in order to investigate the prognostic value of the apoptosis-related gene expression and the tumor proliferative maker, and the relationships among these IHC results and patients clinical characteristics, chemoresponsiveness, and survival were analyzed. The medical records of 107 patients were reviewed retrospectively. IHC stainings for p53, bcl-2 and Ki-67 expressions were performed in the 66 paraffin-embedded biopsy samples. Sixty-six out of the 107 patients were evaluable for response rate and survival. The overall response rate was 75% (95% Confidence Interval=74-76%) and the median survival time was 14 months. The median survival time of limited stage was 16 months and that of extensive stage was 10 months. The prevalence of p53, bcl-2 and Ki-67 expression was 62%, 70%, and 49%, respectively. There were no correlations among the immunoreactivities of p53, bcl-2 and Ki-67 with clinical stage, chemoresponsiveness or overall survival. The clinical stage was the only prognostic factor influencing survival. The expression rates of p53, bcl-2, and Ki-67 were relatively high in SCLC without any prognostic significance. The exact clinical role of these markers should be defined through further investigations.
Adult ; Aged ; Carcinoma, Small Cell/metabolism/*pathology ; Female ; Humans ; Immunohistochemistry ; Ki-67 Antigen/analysis ; Lung Neoplasms/metabolism/*pathology ; Male ; Middle Aged ; Multivariate Analysis ; Prognosis ; Proto-Oncogene Proteins c-bcl-2/analysis ; Survival Analysis ; Tumor Markers, Biological/*analysis ; Tumor Suppressor Protein p53/analysis

BACKGROUND/AIMS: Although erythrocyte sedimentation rate (ESR) is included as a laboratory parameter in Truelove and Witts' classification, C-reactive protein (CRP) is also used for severity assessment in ulcerative colitis (UC). Frequently, the discordance between ESR and CRP is observed in clinical practice. The aim of this study was to determine which parameter is more related with clinical activity in UC patients. METHODS: A total of 155 patients with UC were identified from January 2004 to March 2005. Their medical records were reviewed within these patients, a total of 541 assessments of disease activity were made. Correlation of clinical activity and laboratory tests were evaluated by Pearson's correlation coefficient. RESULTS: Pearson's correlation coefficients of ESR and CRP with clinical symptoms were 0.376 and 0.258, respectively. The correlation coefficient between ESR and CRP was 0.403 (p=0.000). A total of 131 (24.2%) assessments revealed discordance between ESR and CRP. When discordance occurred, the correlation coefficients with clinical symptoms were 0.338 for ESR (p=0.000) and 0.034 for CRP (p>0.01). Dividing discordant patients into high ESR/low CRP group and low ESR/high CRP group, the coefficients were 0.420 for ESR and 0.226 for CRP in high ESR/low CRP group, and 0.333 for ESR and 0.068 for CRP in low ESR/high CRP group. CONCLUSIONS: The correlation analysis indicates that ESR appears to be a more reliable laboratory parameter of disease activity than CRP in assessing the severity of UC. In particular, when the level of ESR and CRP is discordant, ESR is more useful in assessing the disease activity in UC patients.
*Blood Sedimentation ; C-Reactive Protein/*analysis ; Colitis, Ulcerative/blood/*diagnosis ; Humans ; Severity of Illness Index

BACKGROUND: In spite of active HIV/AIDS control and managements, UNAIDS estimate that 40 million people were living worldwide with HIV at the end of 2001. In Korea, The member of HIV- infected adults are continuously growing. For improvement of HIV screening and prevention, we analyzed over times the relationship between the changes in initial CD4+ T cell counts of newly HIV- diagnosed adults, sex, and exposure route. METHODS: We selected 1011 newly HIV-diagnosed adults whose initial CD4+ T cell count was determined within 6 months of HIV diagnosis between 1990 and June, 2002. Based on CD4+ T cell counts, the selected people were grouped into 4 as follows: <200 cells/mm3, 200-349 cells/mm3, 350-699 cells/mm3, and >700 cells/mm3. The relationship between initial CD4+ T cell counts, age, sex, and HIV risk category were studied by regression statistic methods. RESULTS: The median initial CD4+ T cell counts decreased over times (P<0.001). In each major group, over 50% of initial CD4+ T cell counts were below 350 cells/mm3. For homosexually infected adults, the median age did not statistically increase (P=0.062). However, in heterosexually infected adults, the median age increased throughout the time period examined (P<0.001) with an exception of female group (P=0.427). The multi-regression analyses revealed that older age (P<0.001) and male sex (P<0.001) were independently associated with lower initial CD4+ T cell counts, but not exposure group (P=0.483). For each year cohort of newly diagnosed adults, the median initial CD4+ T cell counts in subsequent years decreased until 1998 and then increased thereafter. CONCLUSION: These results show that a large proportion of HIV-infected adults are being diagnosed late in the course of HIV infection, particularly heterosexually infected male group. Therefore, we should continuously enforce screening, prevention and prompt diagnosis of high risk groups.
Adult ; Cell Count* ; Cohort Studies ; Diagnosis ; Female ; HIV ; HIV Infections ; Homosexuality ; Humans ; Korea ; Male ; Mass Screening