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.

Objective: To evaluate the signal intensity of the periosteum using ultrashort echo time pulse sequence with threedimensional cone trajectory (3D UTE) with or without fat suppression (FS) to distinguish from artifacts in porcine tibias. Materials and Methods: The periosteum and overlying soft tissue of three porcine lower legs were partially peeled away from the tibial cortex. Another porcine tibia was prepared as three segments: with an intact periosteum outer and inner layer, with an intact periosteum inner layer, and without periosteum. Axial T1 weighted sequence (T1 WI) and 3D UTE (FS) were performed. Another porcine tibia without periosteum was prepared and subjected to 3D UTE (FS) and T1 WI twice, with positional changes. Two radiologists analyzed images to reach a consensus. Results: The three periosteal tissues that were partially peeled away from the cortex showed a high signal in 3D UTE (FS) and low signal on T1 WI. 3D UTE (FS) showed a high signal around the cortical surface with an intact outer and inner periosteum, and subtle high signals, mainly around the upper cortical surfaces with the inner layer of the periosteum and without periosteum. T1 WI showed no signal around the cortical surfaces, regardless of the periosteum state. The porcine tibia without periosteum showed changes in the high signal area around the cortical surface as the position changed in 3D UTE (FS). No signal was detected around the cortical surface in T1 WI, regardless of the position change. Conclusion The periosteum showed a high signal in 3D UTE and 3D UTE FS that overlapped with artifacts around the cortical bone.

Purpose: Despite aggressive medical and nutritional management, patients with methylmalonic acidemia (MMA) often suffer from multi-organ damage. Early deceased donor liver transplantation (DDLT) has emerged as an intervention to prevent disease progression. We investigated the efficacy of living donor LT (LDLT) with a potential carrier of MMA and a small volume of graft in patients with MMA as an alternative to DDLT. Methods: Of five patients (three male, two female; median age 5.7 years; range, 1.3–13.7 years), four underwent carrier LDLT, while one underwent non-carrier auxiliary LDLT. All patients received pre- and post-LT continuous renal replacement therapy and were provided with minimal restriction diet according to serum MMA level after LT. MMA levels in the serum and urine, the incidence of metabolic crisis, and clinical findings before and after LT were compared. Results: The survival rate was 100% during 2.2 years of follow up period after LT. In all five cases, MMA titer in the serum after transplantation decreased with less restrictive diet. Metabolic crisis was not observed during the follow-up period. In addition, no patient showed progression of severe renal impairment requiring hemodialysis. Progression of delayed cognitive development was not observed. Social functioning with improved neuropsychiatric development was observed. Conclusion This study showed that LDLT achieved improved quality of life with less restrictive diet, therefore it could be a feasible alternative option to DDLT for the treatment of patients with MMA, even with an auxiliary LT.

Objective: To evaluate the signal intensity of the periosteum using ultrashort echo time pulse sequence with threedimensional cone trajectory (3D UTE) with or without fat suppression (FS) to distinguish from artifacts in porcine tibias. Materials and Methods: The periosteum and overlying soft tissue of three porcine lower legs were partially peeled away from the tibial cortex. Another porcine tibia was prepared as three segments: with an intact periosteum outer and inner layer, with an intact periosteum inner layer, and without periosteum. Axial T1 weighted sequence (T1 WI) and 3D UTE (FS) were performed. Another porcine tibia without periosteum was prepared and subjected to 3D UTE (FS) and T1 WI twice, with positional changes. Two radiologists analyzed images to reach a consensus. Results: The three periosteal tissues that were partially peeled away from the cortex showed a high signal in 3D UTE (FS) and low signal on T1 WI. 3D UTE (FS) showed a high signal around the cortical surface with an intact outer and inner periosteum, and subtle high signals, mainly around the upper cortical surfaces with the inner layer of the periosteum and without periosteum. T1 WI showed no signal around the cortical surfaces, regardless of the periosteum state. The porcine tibia without periosteum showed changes in the high signal area around the cortical surface as the position changed in 3D UTE (FS). No signal was detected around the cortical surface in T1 WI, regardless of the position change. Conclusion The periosteum showed a high signal in 3D UTE and 3D UTE FS that overlapped with artifacts around the cortical bone.

Purpose: Despite aggressive medical and nutritional management, patients with methylmalonic acidemia (MMA) often suffer from multi-organ damage. Early deceased donor liver transplantation (DDLT) has emerged as an intervention to prevent disease progression. We investigated the efficacy of living donor LT (LDLT) with a potential carrier of MMA and a small volume of graft in patients with MMA as an alternative to DDLT. Methods: Of five patients (three male, two female; median age 5.7 years; range, 1.3–13.7 years), four underwent carrier LDLT, while one underwent non-carrier auxiliary LDLT. All patients received pre- and post-LT continuous renal replacement therapy and were provided with minimal restriction diet according to serum MMA level after LT. MMA levels in the serum and urine, the incidence of metabolic crisis, and clinical findings before and after LT were compared. Results: The survival rate was 100% during 2.2 years of follow up period after LT. In all five cases, MMA titer in the serum after transplantation decreased with less restrictive diet. Metabolic crisis was not observed during the follow-up period. In addition, no patient showed progression of severe renal impairment requiring hemodialysis. Progression of delayed cognitive development was not observed. Social functioning with improved neuropsychiatric development was observed. Conclusion This study showed that LDLT achieved improved quality of life with less restrictive diet, therefore it could be a feasible alternative option to DDLT for the treatment of patients with MMA, even with an auxiliary LT.

Despite the great socioeconomic burden of stroke, there have been few reports of stroke statistics in Korea. In this scenario, the Epidemiologic Research Council of the Korean Stroke Society launched the “Stroke Statistics in Korea” project, aimed at writing a contemporary, comprehensive, and representative report on stroke epidemiology in Korea. This report contains general statistics of stroke, prevalence of behavioral and vascular risk factors, stroke characteristics, pre-hospital system of care, hospital management, quality of stroke care, and outcomes. In this report, we analyzed the most up-to-date and nationally representative databases, rather than performing a systematic review of existing evidence. In summary, one in 40 adults are patients with stroke and 232 subjects per 100,000 experience a stroke event every year. Among the 100 patients with stroke in 2014, 76 had ischemic stroke, 15 had intracerebral hemorrhage, and nine had subarachnoid hemorrhage. Stroke mortality is gradually declining, but it remains as high as 30 deaths per 100,000 individuals, with regional disparities. As for stroke risk factors, the prevalence of smoking is decreasing in men but not in women, and the prevalence of alcohol drinking is increasing in women but not in men. Population-attributable risk factors vary with age. Smoking plays a role in young-aged individuals, hypertension and diabetes in middle-aged individuals, and atrial fibrillation in the elderly. About four out of 10 hospitalized patients with stroke are visiting an emergency room within 3 hours of symptom onset, and only half use an ambulance. Regarding acute management, the proportion of patients with ischemic stroke receiving intravenous thrombolysis and endovascular treatment was 10.7% and 3.6%, respectively. Decompressive surgery was performed in 1.4% of patients with ischemic stroke and in 28.1% of those with intracerebral hemorrhage. The cumulative incidence of bleeding and fracture at 1 year after stroke was 8.9% and 4.7%, respectively. The direct costs of stroke were about ₩1.68 trillion (KRW), of which ₩1.11 trillion were for ischemic stroke and ₩540 billion for hemorrhagic stroke. The great burden of stroke in Korea can be reduced through more concentrated efforts to control major attributable risk factors for age and sex, reorganize emergency medical service systems to give patients with stroke more opportunities for reperfusion therapy, disseminate stroke unit care, and reduce regional disparities. We hope that this report can contribute to achieving these tasks.
Adult ; Aged ; Alcohol Drinking ; Ambulances ; Atrial Fibrillation ; Cerebral Hemorrhage ; Emergency Medical Services ; Emergency Service, Hospital ; Epidemiology ; Female ; Hemorrhage ; Hope ; Humans ; Hypertension ; Incidence ; Korea ; Male ; Mortality ; Prevalence ; Reperfusion ; Risk Factors ; Smoke ; Smoking ; Stroke ; Subarachnoid Hemorrhage ; Writing

BACKGROUND/AIMS: Colorectal cancer is associated with different anatomical, biological, and clinical characteristics. We determined the impact of the primary tumor location in patients with metastatic colorectal cancer (mCRC). METHODS: Demographic data and clinical information were collected from 1,115 patients from the Republic of Korea, who presented with mCRC between January 2009 and December 2011, using web-based electronic case report forms. Associations between the primary tumor location and the patient's clinical characteristics were assessed, and factors inf luencing overall survival were analyzed using Cox proportional hazards regression models. RESULTS: Of the 1,115 patients recruited to the study, 244 (21.9%) had right colon cancer, 483 (43.3%) had left colon cancer, and 388 (34.8%) had rectal cancer. Liver and lung metastases occurred more frequently in patients with left colon and rectal cancer (p = 0.005 and p = 0.006, respectively), while peritoneal and ovarian metastases occurred more frequently in patients with right and left colon cancer (p < 0.001 and p = 0.031, respectively). The median overall survival of patients with tumors originating in the right colon was significantly shorter than that of patients whose tumors had originated in the left colon or rectum (13.7 months [95% confidence interval (CI), 12.0 to 15.5] vs. 18.0 months [95% CI, 16.3 to 19.7] or 19.9 months [95% CI, 18.5 to 21.3], respectively; p = 0.003). Tumor resection, the number of metastatic sites, and primary tumor location correlated with overall survival in the univariate and multivariate analyses. CONCLUSIONS: Primary tumor location influences the metastatic sites and prognosis of patients with mCRC.
Colon ; Colonic Neoplasms ; Colorectal Neoplasms* ; Humans ; Liver ; Lung ; Multivariate Analysis ; Neoplasm Metastasis ; Prognosis ; Rectal Neoplasms ; Rectum ; Republic of Korea

Müllerian duct aplasia-renal aplasia-cervicothoracic somite dysplasia (MURCS) association is a unique development disorder with four common types of malformations that include uterine aplasia or hypoplasia, renal ectopy or agenesis, vertebral anomalies, and short stature. The majority of MURCS patients are diagnosed with primary amenorrhea from late-adolescence. However, a few cases with MURCS association are not well diagnosed during childhood and long-term outcomes are not well reported. We report a case of an 8-year-old girl with MURCS association who presented with recurrent urinary tract infections and multiple congenital malformations, and who was followed for 10 years until adulthood. MURCS association should be considered as one of the differential diagnoses when evaluating prepubertal females with vertebral and renal malformations.
Amenorrhea ; Child ; Diagnosis, Differential ; Female ; Follow-Up Studies ; Humans ; Somites ; Urinary Tract Infections

BackgroundUntil now, various types of combined therapy with nucleotide analogs and pegylated interferon (Peg-INF) in patients with hepatitis B patients have been tried. However, studies regarding the benefits of de novo combination, late-add on, and sequential treatment are very limited. The objective of the current study was to identify the efficacy of sequential treatment of Peg-INF after short-term antiviral treatment.

MethodsBetween June 2010 and June 2015, hepatitis B e antigen (HBeAg)-positive patients (n = 162) received Peg-IFN for 48 weeks (mono-treatment group, n = 81) and entecavir (ETV) for 12 weeks with a 48-week course of Peg-IFN starting at week 5 of ETV therapy (sequential treatment group, n = 81). The primary endpoint was HBeAg seroconversion at the end of follow-up period after the 24-week treatment. The primary endpoint was analyzed using Chi-square test, Fisher's exact test, and regression analysis.

ResultsHBeAg seroconversion rate (18.2% vs. 18.2%, t = 0.03, P = 1.000) and seroclearance rate (19.7% vs. 19.7%, t = 0.03, P = 1.000) were same in both mono-treatment and sequential treatment groups. The rate of alanine aminotransferase (ALT) normalization (45.5% vs. 54.5%, t = 1.12, P = 0.296) and serum hepatitis B virus (HBV)-DNA <2000 U/L (28.8% vs. 28.8%, t = 0.10, P = 1.000) was not different in sequential and mono-treatment groups at 24 weeks of Peg-INF. Viral response rate (HBeAg seroconversion and serum HBV-DNA <2000 U/L) was not different in the two groups (12.1% vs. 16.7%, t = 1.83, P = 0.457). Baseline HBV-DNA level (7 logU/ml vs. 7.5 logU/ml, t = 1.70, P = 0.019) and hepatitis B surface antigen titer (3.6 logU/ml vs. 4.0 logU/ml, t = 2.19, P = 0.020) were lower and predictors of responder in mono-treatment and sequential treatment groups, respectively.

ConclusionsThe current study shows no differences in HBeAg seroconversion rate, ALT normalization, and HBV-DNA levels between mono-therapy and sequential therapy regimens.

Trial RegistrationClinicalTrials.gov, NCT01220596; https://clinicaltrials.gov/ct2/show/NCT01220596?term=NCT01220596&rank=1.

No abstract available.
Coronary Vessels* ; Pulmonary Artery*