Viral load and the duration of viral shedding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are important determinants of the transmission of coronavirus disease 2019.In this study, we examined the effects of viral doses on the lung and spleen of K18-hACE2 transgenic mice by temporal histological and transcriptional analyses. Approximately, 1×105 plaque-forming units (PFU) of SARS-CoV-2 induced strong host responses in the lungs from 2 days post inoculation (dpi) which did not recover until the mice died, whereas responses to the virus were obvious at 5 days, recovering to the basal state by 14 dpi at 1×102 PFU. Further, flow cytometry showed that number of CD8+ T cells continuously increased in 1×102 PFU-virusinfected lungs from 2 dpi, but not in 1×105 PFU-virus-infected lungs. In spleens, responses to the virus were prominent from 2 dpi, and number of B cells was significantly decreased at 1×105PFU; however, 1×102 PFU of virus induced very weak responses from 2 dpi which recovered by 10 dpi. Although the defense responses returned to normal and the mice survived, lung histology showed evidence of fibrosis, suggesting sequelae of SARS-CoV-2 infection. Our findings indicate that specific effectors of the immune response in the lung and spleen were either increased or depleted in response to doses of SARS-CoV-2. This study demonstrated that the response of local and systemic immune effectors to a viral infection varies with viral dose, which either exacerbates the severity of the infection or accelerates its elimination.

PURPOSE: The purpose of this study was to evaluate potential prognostic factors in patients with adenoid cystic carcinoma (ACC). MATERIALS AND METHODS: A total of 68 patients who underwent curative surgery and had available tissue were enrolled in this study. Their medical records and pathologic slides were reviewed and immunohistochemistry for basic fibroblast growth factor, fibroblast growth factor receptor (FGFR) 2, FGFR3, c-kit, Myb proto-oncogene protein, platelet-derived growth factor receptor beta, vascular endothelial growth factor (VEGF), and Ki-67 was performed. Univariate and multivariate analysis was performed for determination of disease-free survival (DFS) and overall survival (OS). RESULTS: In univariate analyses, primary site of nasal cavity and paranasal sinus (p=0.022) and Ki-67 expression of more than 7% (p=0.001) were statistically significant factors for poor DFS. Regarding OS, perineural invasion (p=0.032), high expression of VEGF (p=0.033), and high expression of Ki-67 (p=0.007) were poor prognostic factors. In multivariate analyses, primary site of nasal cavity and paranasal sinus (p=0.028) and high expression of Ki-67 (p=0.004) were independent risk factors for poor DFS, and high expression of VEGF (p=0.011) and Ki-67 (p=0.011) showed independent association with poor OS. CONCLUSION: High expression of VEGF and Ki-67 were independent poor prognostic factors for OS in ACC.
Adenoids* ; Carcinoma, Adenoid Cystic* ; Disease-Free Survival ; Fibroblast Growth Factor 2 ; Humans ; Immunohistochemistry ; Medical Records ; Multivariate Analysis ; Nasal Cavity ; Prognosis ; Proto-Oncogenes ; Receptors, Fibroblast Growth Factor ; Receptors, Platelet-Derived Growth Factor ; Risk Factors ; Vascular Endothelial Growth Factor A*

PURPOSE: This research sought to identify the utility value of chest computed tomography (CT) when it comes to the diagnosis of lung metastasis in cases of colorectal cancer. METHODS: From September 2004 to January 2008, 266 patients who were treated for colorectal cancer at Department of Surgery, Hanyang University College of Medicine, were divided into two groups: one that underwent preoperative and postoperative periodical chest CT (periodical inspection group, PIG; May 2006 to January 2008, 135 patients) and one that did not undergo periodical chest CT (non-periodical inspection group, NPIG; September 2004 to April 2006, 131 patients) for comparison. RESULTS: The overall lung metastasis diagnosis rates did not manifest any significant difference. The times to diagnose lung metastasis patients were 6.3 months and 15.7 months for the PIG and the NPIG, respectively (P = 0.022). The size of the metastatic lung nodule was smaller in the PIG than in the NPIG (< 1 cm in 9/9 patients vs. < 1 cm in 6/9 patients in the PIG and the NPIG, respectively; P = 0.02). A solitary lung metastasis was more frequently found in the PIG (5/9 patients) than in the NPIG (1/11 patients) (P = 0.024). During the follow-up period, 100% (2/2 patients) and 60% (3/5 patients) of the patients in the PIG and the NPIG, respectively, with stage III cancer underwent a lung metastasectomy (P = 0.002). CONCLUSION: Chest CT enables early diagnosis with a smaller size and a lower number of lung metastases in patients with colorectal cancer. Moreover, pulmonary the rate of the pulmonary resection for selected patients may be improved. However, the contribution of chest CT to increasing the survival rate must be investigated in a prospective randomized study.
Colorectal Neoplasms ; Early Diagnosis ; Follow-Up Studies ; Humans ; Lung ; Metastasectomy ; Neoplasm Metastasis ; Prospective Studies ; Survival Rate ; Thorax

Recently, the survival rates of extremely low-birth-weight (ELBW) infants have improved with the development of neonatal intensive care. However, these infants were susceptible to intestinal perforation due to prematurity, fluid restriction, and injection of indomethacin, etc. Because of the risks of transportation, anesthesia and surgery itself, peritoneal drainage has been compared with laparotomy. Through our experience, we investigate the usefulness of peritoneal drainage retrospectively. From 1997 to 2007, six ELBW (M:F=5:1) underwent primary peritoneal drainage for intestinal perforation. Their median birth weight was 685 g (405~870) and gestational age was 25(+1) weeks (24(+3)~27(+0)). We noticed the intestinal perforation at median 10.5 days (8~18) after birth, and placed Penrose drain or Jackson-Pratt drain through right lower quadrant incision under local anesthesia. The cause of intestinal perforation was necrotizing enterocolitis in one patient, but that of the others was not clear. Three patients who showed normal platelet count and stable vital signs recovered uneventfully. Two patients (birth weight less than 500 g) who showed unstable vital signs and low platelet count (12,000 / mm3 to 30,000 / mm3) expired despite aggressive resuscitation. One patient required laparotomy due to persistent intestinal obstruction after drain removal and survived. Our experience shows that peritoneal drainage was an acceptable treatment for ELBW infants and the prognosis was related to vital sign and platelet count at the time of intestinal perforation, and birth weight.
Anesthesia ; Anesthesia, Local ; Birth Weight ; Drainage ; Enterocolitis, Necrotizing ; Gestational Age ; Humans ; Indomethacin ; Infant ; Infant, Low Birth Weight ; Infant, Newborn ; Intensive Care, Neonatal ; Intestinal Obstruction ; Intestinal Perforation ; Laparotomy ; Parturition ; Platelet Count ; Prognosis ; Resuscitation ; Retrospective Studies ; Survival Rate ; Transportation ; Vital Signs

Primary urethral carcinoma accounts for less than 1% of the malignancies in males and adenocarcinoma accounts for 5% of all urethral carcinomas. A 36-year-old man with a history suggestive of urethral stricture was scheduled to undergo retrograde urethrography and visual urethrotomy. On urethroscopic examination, an abnormal polypoid mass was found in the proximal bulbous urethra, so transurethral resection biopsy was added to the urethrotomy. Histopathologic examination demonstrated urethral adenocarcinoma with no invasion to the corpus spongiosum and cavernosa on the magnetic resonance imaging. There was no evidence of metastasis and the search for the primary focus of adenocarcinoma revealed that the tumor originated from the urethra. The patient underwent segmental urethral resection and there has been no recurrence for 1-year follow-up.
Adenocarcinoma* ; Adult ; Biopsy ; Follow-Up Studies ; Humans ; Magnetic Resonance Imaging ; Male ; Neoplasm Metastasis ; Recurrence ; Urethra ; Urethral Stricture

PURPOSE: We wished to develop the web based Picture Archiving and Communication System in the emergency room for early decision making in emergency treatment planning at a full PACS Hospital. MATERIALS AND METHODS: The program tools were Microsoft Visual Studio 6.0 - Visual C++ 6.0, and the Microsoft SQL 7.0 under the Microsoft Windows 2000 server(R) operation system. The achievement of images was performed by an auto transport program installed in the ER and the radiology department. RESULTS: The average compression rates were 5:1 for CT and MR, and 20:1 for CR with JPEG 2000 lossy compression. All the images were stored on hard disk for 3 months. The patients' information was displayed for 2 weeks for reducing the security risk. For interdepartmental consultation, patient query by patient hospital number was available. CONCLUSION: Our Web based ER PACS could be useful system for early decision making for treatment planning in the emergency room because it reduces the risk factors for the security of the Web PACS by using a system independent from PACS in the hospital and minimizing the information patients.
Decision Making ; Emergencies* ; Emergency Service, Hospital* ; Emergency Treatment ; Humans ; Risk Factors

STATEMENT OF PROBLEM: One of the common problems of dental implant prosthesis is the loosening of the screw that connects each component, and this problem is more common in single implant-supported prostheses with external connection. PURPOSE: The purpose of this study was to examine the changes of detorque values of abutment screws with external connection in different abutment heights. MATERIALS AND METHODS: After cyclic loading on three different abutment heights, detorque values were measured. Abutments were retained with titanium abutment screws tightened to 30 Ncm (30.5 kgmm) with digital torque gauge as recommended by the manufacturer. Replacing abutments, implants and titanium abutment screws with new ones at every measurement, initial detorque values were measured six times. In measuring detorque values after cyclic loading, Avana Cemented Abutments of 4.0 mm collar, 7.0 mm height (Osstem Co., Ltd., Seoul, Korea) were used with three different lengths of 5.0, 8.0, 11.0 mm. Shorter abutments were made by milling of 11.0 mm abutment to have the same force-exercised area of 4.5 mm diameter. Sine curve force (20N-320N, 14Hz) was applied, and detorque values were measured after cyclic loading of 2 million times by loading machine. Detorque values of initial and after-loading were measured by digital torque gauge. One-way ANOVA was employed to see if there was any influence from different abutment heights. RESULTS: The results were as follows : 1. The initial detorque value was 27.8+/-0.93 kgmm, and the ratio of the initial detorque value to the tightening torque was 0.91(27.8/30.5). 2. Measured detorque values after cyclic loading were declined as the height of the abutment increased, that was, 5.0 mm; 22.3+/-0.82 kgmm, 8.0 mm; 21.8+/-0.93 kgmm, and 11.0 mm; 21.3+/-0.94 kgmm. 3. One-way ANOVA showed no statistically significant differences among these (p> 0.05). 4. Noticeable mobility at the implant-abutment interface was not observed in any case after cyclic loading at all.
Dental Implants ; Prostheses and Implants* ; Seoul ; Titanium ; Torque

PURPOSE: To report the early results of preopeartive concurrent radio-chemotherapy (CRCT) for treating rectal cancer. MATERIALS AND METHODS: From June 1999 to April 2002, 40 rectal cancer patients who either had lesions with a questionable resectability or were candidates for sphincter-sacrificing surgery received preoperative CRCT. Thirty-seven patients completed the planned CRCT course. 45 Gy by 1.8 Gy daily fraction over 5 weeks was delivered to the whole pelvis in the prone position. The chemotherapy regimens were oral UFT plus oral leucovorin (LV) in 12 patients, intravenous bolus 5-FU plus LV in 10 patients, and intravenous 5-FU alone in 15 patients (bolus infusion in 10, continuous infusion in 5). Surgery was planned in 4~6 weeks of the completion of the preoperative CRCT course, and surgery was attempted in 35 patients. RESULTS: The compliance to the current preoperative CRCT protocol was excellent, where 92.5% (37/40) completed the planned treatment. Among 35 patients, in whom surgery was attempted after excluding two patients with new metastatic lesions in the liver and the lung, sphincter-preservation was achieved in 22 patients (62.9%), while resection was abandoned during laparotomy in two patients (5.7%). Gross complete resection was performed in 30 patients, gross incomplete resection was performed in one patient, and no detailed information on the extent of surgery was available in two patients. Based on the surgical and pathological findings, the down-staging rate was 45.5% (15/33), and the complete resection rate with the negative resection margin 78.8% (26/33). During the CRCT course, grade 3~4 neutropenia developed in four patients (10.8%). Local recurrence after surgical resection developed in 12.1% (4/33), and distant metastases after the preoperative CRCT start developed in 21.6% (8/37). The overall 3-years survival rate was 87%. CONCLUSION: Preoperative CRCT in locally advanced rectal cancer is well tolerated and can lead to high resection rate, down-staging rate, sphincter preservation rate, however, longer term follow-up will be necessary to confirm these results.
Compliance ; Drug Therapy ; Fluorouracil ; Follow-Up Studies ; Humans ; Laparotomy ; Leucovorin ; Liver ; Lung ; Neoplasm Metastasis ; Neutropenia ; Pelvis ; Prone Position ; Rectal Neoplasms* ; Recurrence ; Survival Rate

STUDY DESIGN: In-vitro experimental study. OBJECTIVES: To determine the proteoglycan synthesis of the rabbit nucleus pulposus cells in various concentration of extracellular collagen type I and II under the stimulation of TGF-beta1. SUMMARY OF LITERATURE REVIEW: Therapeutic effect of growth factor and gene therapy can be altered by composition of extracellular matrix. However, the effect of extracellular collagen types I and II on synthetic activity of intervertebral disc cells is not thoroughly studied before. MATERIALS AND METHODS: The nucleus pulposus cells were isolated and cultured from 10 skeletally mature rabbits. Cultures were trypsinized and incorporated into alginate beads with different concentration of extracellular collagen type I and II (0.5%, 1.0% and 1.5%). Those cultures with TGF-beta1 (10 ng/ml) served stimulated condition of matrix synthesis. Newly synthesized proteoglycans were assessed by 35 S-sulfate incorporation using chromatography on Sephadex G-25 in PD-10 columns. Scintillation count was normalized with DNA content by Hoechst dye method. RESULTS: In basal condition, difference in proteoglycan synthesis in given concentration of extracellular collagen type I and II were statistically insignificant. In stimulated condition with TGF-beta1, difference in proteoglycan synthesis in given concentration of extracellular collagen type I and II was also statistically insignificant. However, cultures in stimulated condition with TGF-beta1 showed increased amount of newly synthesized proteoglycans compared to those of basal condition regardless of the concentration of extracellular collagen type I and II (p < 0.05). CONCLUSION: Anabolic response of rabbit nucleus pulposus cells is relatively insensitive to extracellular matrix composition, which facilitates application of gene therapy in various conditions of disc degeneration.
Chromatography ; Collagen Type I ; Collagen* ; DNA ; Extracellular Matrix* ; Genetic Therapy ; Intervertebral Disc Degeneration ; Intervertebral Disc* ; Proteoglycans ; Rabbits ; Transforming Growth Factor beta1 ; Trypsin

PURPOSE: The purpose of this study was to evaluate the accuracy and the usefulness of MRI in patients with shoulder injuries. MATERIALS AND METHODS: The sensitivity and the accuracy of MRI in the diagnosis of various lesion were evaluated in 20 patients with shoulder injuries. RESULTS: MRI enabled Bankart lesions and SLAP lesions to be accurately predicted with 100% sensitivity and 90% accuracy in both. However, for types of SLAP lesions, the sensitivity and the accuracy were 60% and 70%, respectively, and for full-thickness or partial-thickness tear of rotator cuff, the sensitivity and the accuracy were 75% in both. MRI was also effective at predicting rotator cuff tear with 100% sensitivity and 95% accuracy. Sensitivity and accuracy for the diagnosis of Hill-Sachs lesion were 91.7% and 90%, respectively. For all lesions except Hill-Sachs lesion, the negative prediction value was higher than the positive prediction value, which means MRI overestimated the lesions. CONCLUSION: MRI was accurate and useful in the prediction of prediction of rotator cuff tear, labral tear and Hill-Sachs lesions. However, for the identification of full-thickness or partial-thickness tear of rotator cuff, and types of SLAP lesions, it was less accurate and less useful.
Diagnosis ; Humans ; Magnetic Resonance Imaging* ; Rotator Cuff ; Shoulder*