Background: The Omicron variant has become the most prevalent SARS-CoV-2 variant. Omicron is known to induce milder lesions compared to the original Wuhan strain. Fatal infection of the Wuhan strain into the brain has been well documented in COVID-19 mouse models and human COVID-19 cases, but apparent infections into the brain by Omicron have not been reported in human adult cases or animal models. In this study, we investigated whether Omicron could spread to the brain using K18-hACE2 mice susceptible to SARS-CoV-2 infection. Results: K18-hACE2 mice were intranasally infected with 1 × 105 PFU of the original Wuhan strain and the Omicron variant of SARS-CoV-2. A follow-up was conducted 7 days post infection. All Wuhan-infected mice showed > 20% body weight loss, defined as the lethal condition, whereas two out of five Omicron-infected mice (40%) lost > 20% body weight. Histopathological analysis based on H&E staining revealed inflammatory responses in the brains of these two Omicron-infected mice. Immunostaining analysis of viral nucleocapsid protein revealed severe infection of neuron cells in the brains of these two Omicron-infected mice. Lymphoid depletion and apoptosis were observed in the spleen of Omicron-infected mice with brain infection. Conclusion Lethal conditions, such as severe body weight loss and encephalopathy, can occur in Omicron-infected K18-hACE2 mice. Our study reports, for the first time, that Omicron can induce brain infection with lymphoid depletion in the mouse COVID-19 model.

PURPOSE: The aim of the present study was to develop a serodiagnostic test for differentiation infected from vaccinated animal (DIVA) strategy accompanying the marker vaccine lacking an immunodominant epitope (IDE) of nucleoprotein of Newcastle disease virus (NDV). MATERIALS AND METHODS: Recombinant epitope-repeat protein (rERP) gene encoding eight repeats of the IDE sequence (ETQFLDLMRAVANSMR) by tetra-glycine linker was synthesized. Recombinant baculovirus carrying the rERP gene was generated to express the rERP in insect cells. Specificity and sensitivity of an indirect enzyme-linked immunosorbent assay (ELISA) employing the rERP was evaluated. RESULTS: The rERP with molecular weight of 20 kDa was successfully expressed by the recombinant baculovirus in an insect-baculovirus system. The rERP was antigenically functional as demonstrated by Western blotting. An indirect ELISA employing the rERP was developed and its specificity and sensitivity was determined. The ELISA test allowed discrimination of NDV infected sera from epitope deletion virus vaccinated sera. CONCLUSION: The preliminary results represent rERP ELISA as a promising DIVA diagnostic tool.
Animals ; Baculoviridae ; Blotting, Western ; Discrimination (Psychology) ; Enzyme-Linked Immunosorbent Assay ; Insects ; Molecular Weight ; Newcastle disease virus* ; Newcastle Disease* ; Nucleoproteins ; Sensitivity and Specificity

PURPOSE: Perinatal hypoxic-ischemic (HI) brain injury remains a common cause of chronic handicapping conditions of cerebral palsy, mental retardation, learning disability, and epilepsy. HI brain injury induces cell death via either necrosis or apoptosis. Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin family. It plays key roles in survival, differentiation, and maintenance of neurons. This study was to investigate the neuroprotective effects of BDNF via the mechanisms of anti-apoptosis in HI brain injury by using cortical astrocyte and neuronal cell culture. METHODS: Cortical astrocytes culture of 1-day-old Sprague-Dawley (SD) rat pups and embryonic cortical neuronal cell culture of SD rats at 14-day gestation were done. The Normoxia group was prepared in 5% CO2 incubators and the Hypoxia group and Hypoxia+BDNF group (after treatment with BDNF for 24 hours) were placed in 1% O2 incubators (94% N2, 5% CO2) for 6 or 18 hours. The expression of Bcl-2 and Bax were assessed by real-time PCR and western blot. The caspase-3 activation was evaluated by caspase activity assay kit. RESULTS: In astrocyte and neuronal cell, the expressions of Bcl-2 in the hypoxia groups were reduced compared to the normoxia groups, whereas, those in the Hypoxia+BDNF groups were increased compared to the hypoxia groups. However, the expressions of Bax and caspase-3 and the ratio of Bax/Bcl-2 were revealed reversely. In astrocyte, Hypoxia group for 6 hours was not significantly altered in Bcl-2, Bax expressions. CONCLUSION: BDNF neuroprotective effects on HI brain injury in neonatal rats may occur via anti-apoptotic mechanism.
Animals ; Anoxia ; Apoptosis ; Astrocytes ; Blotting, Western ; Brain Injuries ; Brain* ; Brain-Derived Neurotrophic Factor* ; Caspase 3 ; Cell Culture Techniques ; Cell Death ; Cerebral Palsy ; Epilepsy ; Humans ; Incubators ; Intellectual Disability ; Learning Disorders ; Necrosis ; Neurons ; Neuroprotective Agents ; Pregnancy ; Rats* ; Rats, Sprague-Dawley ; Real-Time Polymerase Chain Reaction

Three QIAG93 strains, QIAG9301, QIAG9302 and QIAG9303 that have been identified as Getah virus (GETV) are analyzed in this study. The morphological features of three virus isolates were observed by using electron microscopy, suggesting that the QIAG9301, QIAG9302 and QIAG9303 isolate can be classified as tentative member of Alphavirus species in the Semliki Forest complex. The full length of the structural polyprotein gene of each QIAG93 isolate (QIAG9301, QIAG9302 and QIAG9303) was determined that are identical in size, comprising 3759 nucleotides that encoded 1253 amino acids. The sequence analysis of the structural polyprotein gene, including the C, E3, E1, 6K and E2 domain, showed that each QIAG93 isolate shares >98.9% sequence identity. The phylogenetic analysis and evolutionary distance (ED) estimation based on the structural polyprotein gene sequence showed that the QIAG9301 isolate is closely related to GETV South Korea strain (99.9% sequence identity and ED value 0.001) and Chinese GETV YN0540 strain (99.3% sequence identity ED value 0.007) than other Alphavirus species analyzed in this study. Both QIAG9032 and QIAG9303 isolate exhibited genetically close relationship with Mongolian GETV LEIV17741MPR strain (at least 99.3% sequence identity and mean ED value 0.0065). Therefore, our findings will be valuable for molecular epidemiological analyses of GETV in Korea and contribute to a further study on pathogenicity of three QIAG93 isolates in animals.
Alphavirus* ; Amino Acids ; Animals ; Asian Continental Ancestry Group ; Humans ; Korea* ; Microscopy, Electron ; Molecular Epidemiology ; Nucleotides ; Sequence Analysis ; Trees ; Virulence

Hemagglutination inhibition (HI) test employing whole virus antigen is a prescribed serological test for serotyping, diagnosis and surveillance for avian paramyxoviruses (APMVs). For use as alternative to the virus antigen, hemagglutinin-neuraminidase (HN) protein gene of the wild duck isolate APMV-6/WB12-163FS of APMV serotype 6 (APMV-6) was amplified, cloned and expressed in Spodoptera frugiperda insect cells. The HN gene of 1,842 bps in length showed nucleotide and amino acid homology of 93.4% and 97.1%, respectively with that of APMV-6 prototype strain. Putative sialic acid binding motif and potential N-linked glycosylation sites were conserved. In Western blot analysis, the expressed protein had a molecular mass of 66 kDa and reacted specifically with antiserum to APMV-6. In addition, the recombinant HN protein showed biological properties such as hemagglutination (HA) and elution. The recombinant HN protein produced from infected cells showed high HA titers (approximately 2(13) HA unit/ml). The HA activity of the recombinant HN protein was inhibited by antisera to APMV-6. In cross HA inhibition test, the recombinant HN protein had the highest titers with antisera to homologous APMV serotype, although there was weak cross reaction with some of antisera to other APMV serotypes. Our results indicated that recombinant APMV-6 HN protein would have the potential as alternative to the APMV-6 antigen in HI assays.
Avulavirus* ; Baculoviridae* ; Blotting, Western ; Clone Cells ; Cross Reactions ; Diagnosis ; Ducks ; Glycosylation ; Hemagglutination ; HN Protein ; Immune Sera ; Insects ; N-Acetylneuraminic Acid ; Serologic Tests ; Serotyping ; Spodoptera

OBJECTIVES: The aims of this study were to know the prevalence of cognitive disorders in patients with thyroid cancer, and identify related variables to them. METHODS: Subjects were consisted of fourty-two patients with thyroid cancer, who were admitted for radioiodine ablative therapy at 6-12 months after total thyroidectomy. The data were obtained from interviews about history and assessments of depression and cognitive function(Korean Version of the Montreal Cognitive Assessment, MoCA-K). RESULTS: 1) Among subjects, those with below 22 of total score of the MoCA-K were twenty-one(50.0%). 2) Upon age, education, Pre-radioiodine therapy thyroid stimulating hormone(TSH), there were statistically significant difference between subgroup with above 23 of the total MoCA-K score and those below 22. 3) The total scores of the MoCA-K in subjects had significant correlation with age, education, comorbidity, Pre-radioiodine therapy TSH, total score of the HDRS-17. CONCLUSIONS: Cognitive disorders were more prevalent among patients with thyroid cancer before radioiodine therapy. Therefore, further study should be needed to clarify the mechanism for the cognitive disorders in thyroid cancer. Furthermore, physicians should pay attention to the cognitive function and prepare preventative measures for cognitive disorder during management of thyroid cancer.
Carcinoma, Papillary* ; Comorbidity ; Depression ; Education ; Humans ; Prevalence ; Thyroid Gland* ; Thyroid Neoplasms ; Thyroidectomy ; Thyrotropin

The present study was carried out to examine the toxicity and target organs of oral cholera vaccine (OCV) after repeated oral administration in Sprague-Dawley rats for 6 weeks (3 administrations, once every 2 weeks). OCV is an inactivated oral cholera vaccine that contains Vibrio cholerae and confers protection against cholera caused by V. cholera serogroups O1 (Inaba and Ogawa serotypes) and O139 (strain 4260B). The animals were orally administered either OCV placebo (negative control) or OCV at a dose equivalent to 240 times the anticipated human dose. Throughout the administration period, no significant change was detected in clinical signs, body weight, food or water consumption, urinalysis results, hematological and clinical biochemistry test results, organ weights, necropsy, or histopathological examination results. Minor changes were found in hematological and clinical biochemistry tests; however, these changes were within normal ranges. The above results suggest that oral administration of OCV in rats did not induce any toxicologically meaningful changes, and the target organs could not be determined. This study was conducted in accordance with the guidelines established by Good Laboratory Practice (2009-183, KFDA, December 22, 2009) and the OECD Principles of Good Laboratory Practice (1997).
Administration, Oral ; Animals ; Biochemistry ; Body Weight ; Cholera ; Drinking ; Humans ; Organ Size ; Rats ; Rats, Sprague-Dawley ; Reference Values ; Urinalysis ; Vibrio cholerae

OBJECTIVES: We have investigated the toxic effects of the inhalation of subchronic and acute levels of n-octane. METHODS: The rats were exposed to n-octane of 0, 2.34, 11.68 and 23.36 mg/L (n = 5 rats/group/gender) in an acute inhalation test (Organization for Economic Co-operation and Development (OECD) TG 403), or to 0, 0.93, 2.62 and 7.48 mg/L (n = 10 rats/group/gender) for a subchronic inhalation test (OECE TG 413), to establish a national chemical management system consistent with the Globally Harmonized Classification System (GHS). RESULTS: Acutely-exposed rats became lethargic but recovered following discontinuation of inhalation. Other clinical symptoms such as change of body weight and autopsy finds were absent. The LC50 for the acute inhalation toxicity of n-octane was determined to exceed 23.36 mg/L and the GHS category was 'not grouping'. Subchronically-treated rats displayed no significant clinical and histopathological differences from untreated controls; also, target organs were affected hematologically, biochemically and pathologically. Therefore, the no observable adverse effect level was indicated as exceeding 7.48 mg/L and the GHS category was 'not grouping' for the specific target organ toxicity upon repeated exposure. CONCLUSION: However, n-octane exposure should be controlled to be below the American Conference of Industrial Hygienists recommendation (300 ppm) to prevent inhalation-related adverse health effects of workers.
Animals ; Autopsy ; Body Weight ; Inhalation ; Octanes ; Rats

A desmoplastic small round cell tumor (DSRCT) is a rare, aggressive neoplasm that occurs predominantly in children and young men. It presents as a large mass inside the abdomen, particularly within the pelvis, and may be accompanied by extensive tumor implants throughout the peritoneum. Microscopically, it typically appears as nests of small undifferentiated cells within a desmoplastic stroma. A DSRCT shows a special immunohistochemical staining pattern, expressing epithelial, neural, and muscle markers. A DSRCT is associated with a specific chromosomal translocation, t (11;22) (p13;q12), resulting in a chimeric EWS/WT1 transcript that is helpful for diagnosing this tumor. We experienced a case of DSRCT in a 19-year-old man who had been diagnosed with Down's syndrome.
Abdomen ; Child ; Desmoplastic Small Round Cell Tumor ; Down Syndrome ; Humans ; Male ; Muscles ; Pelvis ; Peritoneum ; Translocation, Genetic ; Young Adult

BACKGROUND: The manifestation of Membranoproliperative glomerulonephritis (MPGN) is variable from asymptomatic hematuria, nephrotic syndrome to advanced chronic kidney disease. The etiology, pathogenesis, and treatment of MPGN are unclear. The incidence of idiopathic MPGN is also rare in Korea, and the clinical course was rarely studied. So we investigated clinical course of idiopathic MPGN type 1. METHODS: From March 1990 to November 2004, renal biopsy was done in about 1500 patients in Dong-A universty hospital. Among them, 16 patients were diagnosed as idiopathic MPGN. Fourteen patients were observed over 6 months. We analyzed clinical data of these patients retrospectively. RESULTS: Male to female ratio of total 16 patients is 2.2:1. Mean age of patients was 37.6 years (14-76 years) at the time of diagnosis. Thirteen cases (81%) had nephrotic range proteinuria, 8 cases (50%) had hypertention, 12 cases (75%) had edema, and 4 cases (25%) had decreased renal fuction (serum creatinine>1.2 mg/dL) at the time of diagnosis. Average observation time was 55.7+/-37.4 (6-122)months. Six cases ended up with progressive renal failure. Three cases achieved complete remission. Renal survival time for 50% of cases was 92 months. In our study, edema and decreased renal fucntion at the time of diagnosis were related with later development of progressive renal failure (p<0.05). Of the total 14 cases, 4 cases ware treated conservatively, 6 cases were treated with anti-platelet agents, and 4 cases were treated with anti-platelet agents and prednisone. In conservative treatment group, 1 case ended up with progressive renal failure and 1 case achieved complete remission. In anti-platelet agents treatment goup, 4 cases ended up progressive renal failure. In combined anti-platelet agents and prednisone treatment group, 1 case ended up progressive renal failure and 2 cases achieved complete remission. However, the effect of each treatment is inconclusive because the number of the patients are too small. CONCLUSIONS: We suspect that deceased renal function and edema at the time of diagnosis may be risk factor predicting progressive renal failure in patients with idiopathic MPGN type 1.
Biopsy ; Diagnosis ; Edema ; Female ; Glomerulonephritis ; Glomerulonephritis, Membranoproliferative* ; Hematuria ; Humans ; Incidence ; Korea ; Male ; Nephrotic Syndrome ; Prednisone ; Proteinuria ; Renal Insufficiency ; Renal Insufficiency, Chronic ; Retrospective Studies ; Risk Factors