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.

No abstract available.
Humans ; Multiple Myeloma ; Plasma Cells ; Plasma ; Precursor Cell Lymphoblastic Leukemia-Lymphoma

Bronchial carcinosarcoma is a very rare malignant tumor that is composed of carcinomatous and sarcomatous elements. We describe the first case in which digital tomosynthesis was useful for the evaluation of airway obstruction by bronchial carcinosarcoma that was overlooked on initial chest radiography.
Airway Obstruction* ; Carcinosarcoma* ; Radiography ; Thorax

PURPOSE: This study examined the effect of indirect medical oversight on the quality of prehospital emergency care by emergency medical technicians. METHODS: Indirect medical oversight was applied for a year and 119 rescue run sheets were retrospectively analyzed before and after the program to study the effect of an indirect medical oversight program in one city. The general characteristics of patients who visited hospitals before and after the program were analyzed, along with patient evaluation records, personal data, outbreak patterns, transfer information, direct medical oversight, and emergency medical services (EMS) mobilization reports. In addition, by comparing medical records and the 119 rescue run sheets, changes in the accuracy of 119 rescue run reports, the adequacy of patient classification, and the adequacy of medical direction were analyzed. After gathering these data, statistical analysis was performed and the level of significance was defined as p<0.05. RESULTS: After executing the indirect medical oversight, there was significant improvement in the accuracy of 119 rescue run sheets (p<0.001) and in the consistency of severity classification in 119 rescue run sheets compared with medical records (p=0.016). The adequacy of direct medical oversight request also showed improvement after the indirect medical oversight took effect (p<0.001). However, there was no statistical significance in prehospital procedures. CONCLUSION: Indirect medical oversight significantly improved the quality of emergency medical service by emergency medical technicians. However, the further application and improvement of indirect medical oversight programs are required for the development of prehospital emergency medical care.
Classification ; Emergencies* ; Emergency Medical Services* ; Emergency Medical Technicians* ; Humans ; Medical Records ; Retrospective Studies

Low molecular proteins (LMPs) which are smaller than 20 kDa are difficult to visible on a standard two-dimensional SDS-polyacrylamide gel electrophoresis (2-D SDS-PAGE) map. LMPs must be enriched appropriately to be analyzed. We isolated LMPs of Helicobacter pylori 26695 from 1-D polyacrylamide gel and digested by pepsin. Pepsin-digested LMPs were separated by HPLC and each fraction was analyzed by hybrid tandem mass spectrometer. Seventy nine peptides, representing 27 genes, including copper ion binding protein (CopP, 7 kDa), thioredoxin (TrxA, 11.9 kDa) and ribosomal protein L23 (Rpl23, 10.5 kDa) were identified. Some proteins larger than 40 kDa including Omp2, Omp21, Omp27, Omp30, Omp32, catalase and HP1083 were also identified. This work may give researchers a useful way to analyse the expressed LMPs which could not be identified on the conventional 2-D SDS-PAGE.
Acrylic Resins ; Carrier Proteins ; Catalase ; Chimera ; Chromatography, High Pressure Liquid ; Chromatography, Liquid ; Copper ; Electrophoresis ; Electrophoresis, Polyacrylamide Gel ; Helicobacter pylori ; Molecular Weight ; Pepsin A ; Peptides ; Proteins ; Proteome ; Ribosomal Proteins ; Thioredoxins

BACKGROUND AND OBJECTIVES: This study was done to evaluate the safety of Gore-Tex as a nasal implant. Materials and METHOD: A retrospective multicenter study was carried out on 15 surgeons from 11 general hospitals and 4 private practice clinics regarding the safety of the Gore-Tex as a nasal implant. The study involved 853 patients, of whom 656 received primary surgery and 197 revision surgery. Gore-Tex was mainly used as a dorsal implant in a form of sheet or as a reinforced nasal implant. RESULTS: The overall complication rate associated with Gore-Tex was 2.5% (21 cases). Infection was the most common complication (18 cases ; 2.1%) followed by 2 cases of seroma and 1 case of persistent nasal swelling. In 19 out of 21 complication cases, the graft needed removal to control the infection or seroma (91% removal rate). Nine cases of infection developed in both primary cases (1.37%) and in revision cases (4.57%), which suggests a higher association rate between infection and revision cases (p=0.0062). Infection developed within 1 month in 5 cases while 9 cases developed infection after 6 months of operation. Other complications such as aesthetic problems (malpositioning of the implant or dorsal irregularities) were found in 15 cases (1.8%) and hematoma in 1 case. CONCLUSION: The infection rate of Gore-Tex used in rhinoplasty was about 2% and it rose significantly in the revision cases. If infected, almost all of the implanted Gore-Tex needs removal; therefore, we suggest judicious use of Gore-Tex in rhinoplasty.
Hematoma ; Hospitals, General ; Humans ; Polytetrafluoroethylene* ; Private Practice ; Retrospective Studies ; Rhinoplasty* ; Seroma ; Transplants

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

BACKGROUND: It is known that air borne particulates are closely related with the respiratory symptoms and peak expiratory flow (PEF) in patients with respiratory diseases. In Korea, concentrations of airborne dust and inhalable particulates are dramatically increased by the Yellow sand phenomenon, especially in springtime. OBJECTIVE: This study was performed to evaluate the effect of Yellow sand-related airborne dust on the respiratory symptoms and pulmonary function of patients with bronchial asthma. METHOD: 21 non-smoking, tree pollen non-sensitized subjects with bronchial asthma in Seoul were included in this study. For each subject, asthma and rhinoconjunctivitis symptoms were recorded by self-administered standardized questionnaire and by monitoring PEF between April and May 2000. Symptom score and diurnal variability of PEF were compared with the levels of inhalable particulate matter (PM10) checked in that time at 25 points in Seoul. RESULTS: 15 (71.4%) of the enrolled subjects successfully finished this study. There was no statistically significant relationship between the increment of Yellow sand-related PM10 and respiratory symptom or PEF variability. Of the 15 subjects, there were increased symptoms for the eye in 2 (13.3%) subjects, nose in 3 (20.0%), and sinus in 1 (6.7%), which were associated with Yellow sand-related increase of airborne dust levels. 5 (33.3%) subjects showed changes of PEF variability proportional to the change of PM10. CONCLUSION: Meteorological phenomenon related with Yellow sand has a potential risk of aggravating the upper respiratory tract symptoms and of deteriorating pulmonary functions in patients with asthma.
Asthma* ; Dust ; Humans ; Korea ; Nose ; Particulate Matter ; Pollen ; Respiratory System ; Seoul ; Silicon Dioxide* ; Surveys and Questionnaires

PURPOSE: To evaluate normal human gastric wall layers in vitro using magnetic resonance*(MR) imaging, to correlate the results with the histologic findings, and to determine the optimal technique for evaluation of the gastric wall. MATERIALS AND METHODS: Forty-one normal resected gastric specimens obtained from 25 patients were dissected and placed in a polyethylene tube filled with normal saline. MR imaging with four MR sequences, T1-weighted FLASH*(T1FLASH), fat-saturated T1-weighted FLASH, T2-weighted TSE*(T2TSE), and True-FISP, was performed. The number of gastric wall layers and signal intensity of each layer were determined, and after correlating MR images with the histologic findings, the conspicuity of each layer*(mucosa, submucosa, and muscle), the distinction between each layer, and overall image quality were assessed. RESULTS: The gastric wall was shown by TIFLASH to have two (n=6, 14-6%), three (n=31, 75.6%) and four layers (n=4, 9.8%); by fat-saturated TIFLASH to have two (n=6, 14.6%) and three (n=35, 85.4%) ; by T2TSE to have three (n=24, 58.5%), four (n=11, 26.8%), and five (n=6, 14.6%); and by True-FISP to have one (n=2, 4.9%), two (n=8, 19.5%), three (n=23, 56%), four (n=4, 9.8%), and five (n=4, 9.8%) . The signal intensity of each layer at T1FLASH and fat-saturated T1FLASH was high-intermediate from the lumen in two-layer cases, high-low-high/intermediate in three-layer cases, and high-low-high-intermediate in four-layer cases. The signal intensity of each layer at T2TSE was intermediate/high-low-intermediate in three-layer cases, intermediate low-high-intermediate/low in four-layer cases, and low-high-low-high-low in five-layer cases. Three-layered gastric wall corresponded mostly to mucosa, submucosa, and muscle from the inner to outer layers, respectively. T1FLASH, fat-saturated T1FLASH, and T2TSE were superior to True-FISP in evaluating the gastric wall. T1FLASH and fat-saturated T1FLASH were the best sequences for demonstrating mucosa (p<0.05), and T2TSE was the best for submucosa and the distinction between this and muscle (p<0.05). Both T1FLASH and T2TSE provided the best overall image quality (p<0.05). CONCLUSION: In-vitro MR imaging is an excellent technique for the evaluation of layers of normal gastric wall. T2TSE is the sequence which best demonstrates the conspicuity of submucosa, the distinction between submucosa and muscle, and overall image quality.
Humans ; Magnetic Resonance Imaging* ; Mucous Membrane ; Polyethylene

PURPOSE: We conducted this study to determine the efficacy of conventional treatments for patients with Hodgkin's disease and identify the patients who have poor prognosis and need high-dose chemotherapy and autologous stem cell transplantation. MATERIALS AND METHODS: Between Jun. 1989 and Dec. 1997, 50 patients were enrolled and 39 patients were evaluable. Patients were treated with radiotherapy (5 patients) or combination chemotherapy (21 patients) or combined chemotherapy and radiotherapy (13 patients) according to their disease stage. Chemotherapy regimens were C-MOPP (cyclo- phosphamide, vincristine, procarbazine, and prednisone), MOPP (mechlorethamine, vin- cristine, procarbazine, and prednisone), ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine), alternating C-MOPP/ABVD, and MOPP/ABV hybrid. Radiation therapy was performed when there was residual tumor after chemotherapy or bulky disease. The response to treatments was analyzed by clinical stage I-II and stage III-IV patients group, respectively. RESULTS: The complete response rate was 76.9% for total patients, 83.3% for stage I-II patients, and 71.4% for stage III-IV patients. Of the 30 patients achieving complete response, four (13.3%) relapsed at 6, 12, 22, and 28 months after complete response, respectively. The median follow-up duration was 24 months. Nine patients died. Four patients died of Hodgkins disease. Three-year overall survival rate was 72.9% for total patients, 72.5% for stage I-II patients, and 70% for stage III-IV patients. Two-year disease- free survival rate was 77.6% for total patients, 79% for stage I-II stage patients, and 73.9% for stage III-IV patients. The prognostic factor analysis showed that performance status affected the disease-free survival rate. CONCLUSION: Conventional treatments in patients with Hodgkins disease showed results comparable to previous studies. But we were unable to identify the patients, who need high-dose chemotherapy and autologous stem cell transplantation, because of small number of study patients and short follow up duration.
Bleomycin ; Dimethoate ; Disease-Free Survival ; Drug Therapy ; Drug Therapy, Combination ; Follow-Up Studies ; Hodgkin Disease* ; Humans ; Neoplasm, Residual ; Procarbazine ; Prognosis ; Radiotherapy ; Stem Cell Transplantation ; Survival Rate ; Vinblastine ; Vincristine