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.

Background: Atopic dermatitis (AD) is a heterogeneous disease with different age of onset, disease course, clinical symptoms, severity, and risk of comorbidity. The characteristics of children with AD also vary by age or country. However, little is known about the clinical characteristics of AD in Korean school-aged children and adolescents. Furthermore, there are few studies on phenotypic differences according to onset age. This study aimed to explore the clinical characteristics and phenotypes according to onset age and severity of AD in children and adolescents in Korea. Methods: AD patients aged 6–18 years who presented to 18 hospitals nationwide were surveyed.The patients were examined for disease severity by pediatric allergy specialists, and data on history of other allergic diseases, familial allergy history, onset age, trigger factors, lesion sites,treatment history and quality of life were collected. The results of the patient’s allergy test were also analyzed. The patients were classified into infancy-onset (< 2 years of age), preschoolonset (2–5 years of age), and childhood-onset (≥ 6 years of age) groups. Study population was analyzed for clinical features according to onset-age groups and severity groups. Results: A total of 258 patients with a mean age of 10.62 ± 3.18 years were included in the study. Infancy-onset group accounted for about 60% of all patients and presented significantly more other allergic diseases, such as allergic rhinitis and asthma (P = 0.002 and P = 0.001, respectively). Food allergy symptoms and diagnoses were highly relevant to both earlier onset and more severe group. Inhalant allergen sensitization was significantly associated with both infancy-onset group and severe group (P = 0.012 and P = 0.024, respectively). A family history of food allergies was significantly associated with infancyonset group (P = 0.036). Severe group was significantly associated with a family history of AD, especially a paternal history of AD (P = 0.048 and P = 0.004, respectively). Facial (periorbital, ear, and cheek) lesions, periauricular fissures, hand/foot eczema, and xerosis were associated with infancy-onset group. The earlier the onset of AD, the poorer the quality of life (P = 0.038). Systemic immunosuppressants were used in only 9.6% of the patients in the severe group. Conclusion This study analyzed the clinical features of AD in Korean children and adolescents through a multicenter nationwide study and demonstrated the phenotypic differences according to onset age and severity. Considering the findings that the early-onset group is more severe and accompanied by more systemic allergic diseases, early management should be emphasized in young children and infants.

Polymorphic ventricular tachycardia (PVT) is a fatal arrhythmia that can occur during the treadmill test. This report documents an instance of PVT by the R-on-T phenomenon during an exercise stress test in a 61-year-old male with stable angina pectoris. The subject performed the treadmill test for 581 seconds, and stopped after reaching 115% of the target heart rate. Ischemic ST changes were observed in leads II, III, aVF, and V3-V6 from stage 3. Premature ventricular complexes were noted during the recovery period, with an occurrence of pulseless PVT, reflective of the R-on-T phenomenon. Spontaneous circulation was resumed after unsynchronized cardioversion at 200 J and 2 minutes of cardiopulmonary resuscitation. Emergency coronary angiography revealed 95% stenosis of the proximal right coronary artery, which was fully dilated after percutaneous coronary intervention with a drug-eluting stent. The patient was discharged without any neurologic sequelae.

With increasing need to prevent serious food allergy reactions, Korean food allergen labeling regulation has been revised repeatedly. This paper aims to summarize current statuses of food allergen labeling in Korea and foreign countries and to analyze the issue of food allergen labeling regulation. Korean food labeling regulation currently requires 19 items and 22 foods to be reported on labels (eggs, milk, buckwheat, peanut, soybean, wheat, mackerel, crab, shrimp, pork, peach, tomato, sulfite, walnut, chicken, beef, squid, shellfish, and pine nut). However, some common food triggers (for example, almond, cashew nut, and kiwi fruit) are not included in the current labeling regulation. Another issue is that the Korean labeling regulation has not yet been fully implemented for nonprepacked foods; thus, consumers still have difficulty in correctly identifying allergenic ingredients in food. It should be assessed whether warning statements for cross-contamination are reasonable. To prevent the occurrence of serious reactions from accidental ingestion, efforts must be made to solve recently raised issues including the items required to be listed on food labels, the system of standards for labeling and display methods.
Anacardium ; Arachis ; Chickens ; Decapodiformes ; Eating ; Fagopyrum ; Food Hypersensitivity ; Food Labeling ; Hypersensitivity ; Juglans ; Korea ; Lycopersicon esculentum ; Milk ; Nuts ; Perciformes ; Prunus dulcis ; Prunus persica ; Red Meat ; Shellfish ; Soybeans ; Triticum

BACKGROUND: Anaphylaxis is increasing in young children. The aim of the present study was to analyze the clinical characteristics of anaphylaxis in Korean infants, with a focus on food triggers. METHODS: The study analyzed the medical records of infants aged 0 to 2 years old who had been diagnosed with anaphylaxis in 23 secondary or tertiary hospitals in Korea. RESULTS: We identified 363 cases of infantile anaphylaxis (66.9% male). Cutaneous symptoms were most prevalent (98.6%), followed by respiratory (83.2%), gastrointestinal (29.8%), and neurologic (11.6%) symptoms. Cardiovascular symptoms were noted in 7.7% of the cases. Most of the cases of anaphylaxis (338; 93.1%) were induced by foods. The most common trigger food was cow's milk and cow's milk products (43.8%), followed by hen's eggs (21.9%), walnuts (8.3%), wheat (7.7%), peanuts (4.8%), other nuts (3.0%), and fish (2.1%). In cow's milk-induced anaphylaxis cases, more than half the cases had cow's milk specific immunoglobulin E (sIgE) levels that were lower than the diagnostic decision points (DDPs), which is 5 kUA/L for those under the age of 1 and 15 kUA/L for those over the age of 1. In anaphylaxis induced by hen's egg, most of the cases (91.8%) had hen's egg sIgE levels that were higher than the DDP, which is 2 kUA/L for those under the age of 2 and 7 kUA/L for those over the age of 2. Of the infantile anaphylaxis cases, 46.8% had been treated with epinephrine, and 25.1% had been prescribed an epinephrine auto-injector. CONCLUSION: Cow's milk is the most frequent trigger food of anaphylaxis in Korean infants. However, we found no significant correlation between the sIgE level and clinical severity. Education is required regarding the importance of epinephrine as the first line therapy for anaphylaxis and on properly prescribing epinephrine for infants with a history of anaphylaxis.
Anaphylaxis ; Arachis ; Child ; Education ; Eggs ; Epinephrine ; Humans ; Immunoglobulin E ; Immunoglobulins ; Infant ; Juglans ; Korea ; Medical Records ; Milk ; Nuts ; Ovum ; Retrospective Studies ; Tertiary Care Centers ; Triticum

Food allergy has emerged as an important public health problem affecting people of all ages in many countries. The prevalence varies according to age, geographic regions, and ethnicity. For several years, many studies have suggested that the prevalence of food allergy is increasing at an alarming rate, for unclear reasons. Conversely, some studies have also provided findings that sensitization to common food allergens did not increase. Increased recognition rather than an actual increase in patients with IgE-mediated food allergy might lead to the increases in the prevalence of self-reported or physician-diagnosed food allergy. It is also noted that the prevalence of food allergy differs even in the same region according to the study design, i.e., hospital-based or community-based studies. Despite these limitations, epidemiologic data are important because they provide useful information on diagnosis, treatment, and prevention of food allergy. This review focuses on advances in the epidemiology of food allergy in Korean children.
Allergens ; Child ; Diagnosis ; Epidemiology ; Food Hypersensitivity ; Humans ; Prevalence ; Public Health

PURPOSE: Gastric emptying may influence the quality of life of patients who undergo distal gastrectomy. Little is known, however, about gastric emptying after distal gastrectomy. The aim of our study was to investigate gastric emptying patterns after distal gastrectomy. METHODS: This gastric-emptying study investigated patients who underwent distal gastrectomy in the 6 months or more before May 2008 to July 2013 at Chungbuk National University Hospital with a study sample of 205 patients. We analyzed patterns of gastric emptying. RESULTS: Delayed gastric emptying was found in 109 of the 205 patients (53.2%). Food stasis was more frequent in a group with delayed gastric emptying. In multivariate analysis, risk factors for gastroparesis were laparoscopic operation (hazard ratio [HR], 2.731; P = 0.008) and duration of less than 24 months after distal gastrectomy (HR, 2.795; P = 0.001). Delayed gastric emptying tended to decrease with duration of the postoperative period. CONCLUSION: Delayed gastric emptying is common in distal gastrectomy, and is related to laparoscopic operation and duration of the postoperative period. Food stasis was more frequent in a group with delayed gastric emptying.
Chungcheongbuk-do ; Gastrectomy* ; Gastric Emptying* ; Gastroparesis ; Humans ; Multivariate Analysis ; Postoperative Period ; Quality of Life ; Risk Factors ; Stomach Neoplasms

PURPOSE: Gastric emptying may influence the quality of life of patients who undergo distal gastrectomy. Little is known, however, about gastric emptying after distal gastrectomy. The aim of our study was to investigate gastric emptying patterns after distal gastrectomy. METHODS: This gastric-emptying study investigated patients who underwent distal gastrectomy in the 6 months or more before May 2008 to July 2013 at Chungbuk National University Hospital with a study sample of 205 patients. We analyzed patterns of gastric emptying. RESULTS: Delayed gastric emptying was found in 109 of the 205 patients (53.2%). Food stasis was more frequent in a group with delayed gastric emptying. In multivariate analysis, risk factors for gastroparesis were laparoscopic operation (hazard ratio [HR], 2.731; P = 0.008) and duration of less than 24 months after distal gastrectomy (HR, 2.795; P = 0.001). Delayed gastric emptying tended to decrease with duration of the postoperative period. CONCLUSION: Delayed gastric emptying is common in distal gastrectomy, and is related to laparoscopic operation and duration of the postoperative period. Food stasis was more frequent in a group with delayed gastric emptying.
Chungcheongbuk-do ; Gastrectomy* ; Gastric Emptying* ; Gastroparesis ; Humans ; Multivariate Analysis ; Postoperative Period ; Quality of Life ; Risk Factors ; Stomach Neoplasms

PURPOSE: Age-based causes and clinical characteristics of immediate-type food allergy (FA) have not been sufficiently studied. Therefore, we investigated age-dependent clinical profiles of FA in Korean children through an extensive multicenter investigation. METHODS: Using a case report form developed by the authors, a retrospective medical record review was performed of patients (0-18 years old) diagnosed with immediate-type FA between September 2014 and August 2015 in 14 tertiary hospitals in Korea. RESULTS: A total of 1,353 children and adolescents, 93% younger than 7 years, were enrolled in the present study, and 1,661 cases of immediate-type FA were recorded in these patients. The 7 major causative foods were cow's milk (28.1%), hen's eggs (27.6%), wheat (7.9%), walnuts (7.3%), peanuts (5.3%), buckwheat (1.9%), and shrimps (1.9%). Categorizing the patients into 4 age groups revealed that the most common causative food was different for each age group: cow's milk (<2 years), walnuts (2–6 years), walnuts (7–12 years), and buckwheat (13-18 years). The onset time of symptoms was less than 10 minutes in 49%, between 10 and 30 minutes in 17%, and between 30 minutes and 2 hours in 34% of cases. Food-induced anaphylaxis was reported in 506 (30.5%) out of 1,661 cases, and the 7 major causes of food-induced anaphylaxis was cow's milk (27.5%), hen's eggs (21.9%), wheat (11.3%), walnuts (10.5%), peanuts (5.9%), buckwheat (4.2%), and pine nuts (3.0%). The proportion of anaphylaxis was highest in the patients allergic to buckwheat (67.7%), followed by those allergic to pine nuts (57.7%), walnuts (43.8%), wheat (43.5%), and peanuts (34.1%). CONCLUSIONS: The 5 major causative foods of immediate-type FA in Korean children were cow's milk, hen's eggs, wheat, walnuts, and peanuts. The distribution of causative foods was considerably distinctive according to different age groups. Anaphylaxis was reported in 30.5% of immediate-type FA cases.
Adolescent ; Anaphylaxis ; Arachis ; Child* ; Eggs ; Fagopyrum ; Food Hypersensitivity* ; Humans ; Juglans ; Korea ; Medical Records ; Milk ; Nuts ; Ovum ; Retrospective Studies ; Tertiary Care Centers ; Triticum