• Title/Summary/Keyword: virus spread

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Immune Responses to Viral Infection (바이러스 감염에 대한 면역반응)

  • Hwang, Eung-Soo;Park, Chung-Gyu;Cha, Chang-Yong
    • IMMUNE NETWORK
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    • v.4 no.2
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    • pp.73-80
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    • 2004
  • Viruses are obligate intracellular parasites which cause infection by invading and replicating within cells. The immune system has mechanisms which can attack the virus in extracellular and intracellular phase of life cycle, and which involve both non-specific and specific effectors. The survival of viruses depends on the survival of their hosts, and therefore the immune system and viruses have evolved together. Immune responses to viral infection may be variable depending on the site of infection, the mechanism of cell-to-cell spread of virus, physiology of the host, host genetic variation, and environmental condition. Viral infection of cells directly stimulates the production of interferons and they induce antiviral state in the surrounding cells. Complement system is also involved in the elimination of viruses and establishes the first line of defence with other non-specific immunity. During the course of viral infection, antibody is most effective at an early stage, especially before the virus enters its target cells. The virus- specific cytotoxic T lymphocytes are the principal effector cells in clearing established viral infections. But many viruses have resistant mechanism to host immune responses in every step of viral infection to cells. Some viruses have immune evasion mechanism and establish latency or persistency indefinitely. Furthermore antibodies to some viruses can enhance the disease by the second infection. Immune responses to viral infection are very different from those to bacterial infection.

Histopathological observations and virus detection by in situ hybridization in wild rats intranasally infected with Aujeszky's disease virus isolated in Korea (국내분리 오제스키병 바이러스로 비강접종한 야생집쥐(Rattus norvegicus)의 병리학적 소견 및 in situ hybridization에 의한 바이러스 동정)

  • Song, Geun-seok;Moon, Oun-kyong;Jeong, Chang-geun;Kim, Soon-bok
    • Korean Journal of Veterinary Research
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    • v.39 no.3
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    • pp.531-537
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    • 1999
  • The present study was carried out to investigate the pathogenicity and pathogenesis of wild rats(Rattus norvegicus), trapped in nature, intranasally infected with Aujeszky's disease virus(ADV/NYJ-1-87) by histopathology, immunohistochemistry and in situ hybridization(ISH). Fifteen rats inoculated intranasally were roughened haircoat, anorexia, listlessness, and depression second day after inoculation, and three rats died in 66-72 hours. Eight rats showed severe pruritus at the face that was accompanied by frequent face-washing movements of the forelegs, and then became violent and spasmodic for an hour or until they died. Four rats slowly recovered after showing mild clinical signs of the disease. Microscopic lesions in infected rats were characterized by meningitis, perivascular round cell infiltration, focal gliosis, and neuronal degeneration and necrosis. And intranuclear inclusion bodies were frequently detected in the cerebral cortex and medulla. Positive reaction to ADV by immunohistochemistry and ISH were detected in the following areas : trigermimal ganglion, brain, tonsil, nasal mucosa, spleen, lung and liver. The result has suggested that ADV intranasally infected in wild rats is followed by replication in epithelial calls of nasal mucosa and tonsil, then invade local lymph nodes by way of the lymphatics. It is also believed that the virus invades bipolar olfactory cells and trigerminal ganglion; and then spread into central nervous system.

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Zika Virus-Encoded NS2A and NS4A Strongly Downregulate NF-κB Promoter Activity

  • Lee, Jeong Yoon;Nguyen, Thi Thuy Ngan;Myoung, Jinjong
    • Journal of Microbiology and Biotechnology
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    • v.30 no.11
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    • pp.1651-1658
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    • 2020
  • Since Zika virus (ZIKV) was first detected in Uganda in 1947, serious outbreaks have occurred globally in Yap Island, French Polynesia and Brazil. Even though the number of infections and spread of ZIKV have risen sharply, the pathogenesis and replication mechanisms of ZIKV have not been well studied. ZIKV, a recently highlighted Flavivirus, is a mosquito-borne emerging virus causing microcephaly and the Guillain-Barre syndrome in fetuses and adults, respectively. ZIKV polyprotein consists of three structural proteins named C, prM and E and seven nonstructural proteins named NS1, NS2A, NS2B, NS3, NS4A, NS4B, and NS5 in an 11-kb single-stranded positive sense RNA genome. The function of individual ZIKV genes on the host innate immune response has barely been studied. In this study, we investigated the modulations of the NF-κB promoter activity induced by the MDA5/RIG-I signaling pathway. According to our results, two nonstructural proteins, NS2A and NS4A, dramatically suppressed the NF-κB promoter activity by inhibiting signaling factors involved in the MDA5/RIG-I signaling pathway. Interestingly, NS2A suppressed all components of MDA5/RIG-I signaling pathway, but NS4A inhibited most signaling molecules, except IKKε and IRF3-5D. In addition, both NS2A and NS4A downregulated MDA5-induced NF-κB promoter activity in a dosedependent manner. Taken together, our results suggest that NS2A and NS4A signifcantly antagonize MDA5/RIG-I-mediated NF-κB production, and these proteins seem to be controlled by different mechanisms. This study could help understand the mechanisms of how ZIKV controls innate immune responses and may also assist in the development of ZIKV-specific therapeutics.

Molecular characterization of chicken anemia virus in Guangxi Province, southern China, from 2018 to 2020

  • Zhang, Minxiu;Deng, Xianwen;Xie, Zhixun;Zhang, Yanfang;Xie, Zhiqin;Xie, Liji;Luo, Sisi;Fan, Qing;Zeng, Tingting;Huang, Jiaoling;Wang, Sheng
    • Journal of Veterinary Science
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    • v.23 no.5
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    • pp.63.1-63.14
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    • 2022
  • Background: Chicken anemia virus (CAV) causes chicken infectious anemia, which results in immunosuppression; the virus has spread widely in chicken flocks in China. Objectives: The aim of this study was to understand recent CAV genetic evolution in chicken flocks in Guangxi Province, southern China. Methods: In total, 350 liver samples were collected from eight commercial broiler chicken farms in Guangxi Province in southern China from 2018 to 2020. CAV was detected by conventional PCR, and twenty CAV complete genomes were amplified and used for the phylogenetic analysis and recombination analysis. Results: The overall CAV-positive rate was 17.1%. The genetic analysis revealed that 84 CAVs were distributed in groups A, B, C (subgroups C1-C3) and D. In total, 30 of 47 Chinese CAV sequences from 2005-2020 belong to subgroup C3, including 15 CAVs from this study. There were some specific mutation sites among the intergenotypes in the VP1 protein. The amino acids at position 394Q in the VP1 protein of 20 CAV strains were consistent with the characteristics of a highly pathogenic strain. GX1904B was a putative recombinant. Conclusions: Subgroup C3 was the dominant genotype in Guangxi Province from 2018-2020. The 20 CAV strains in this study might be virulent according to the amino acid residue analysis. These data help improve our understanding of the epidemiological trends of CAV in southern China.

Comparative Evaluation of Measures against the Spread of Air-borne Infections in a Large National Hospital and Small and Medium-sized Clinics in Korea (국내 대형병원과 중·소규모 의원의 공기감염 확산 방지 대책의 비교 평가)

  • An, Jiwon;Yang, Young Kwon;Won, An-Na;Hwang, Jung Ha;Park, Jin Chul
    • Journal of Korean Living Environment System
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    • v.25 no.1
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    • pp.90-97
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    • 2018
  • The purpose of this study is to compare and analyze the air infections in middle and small hospitals with the facilities of large national hospitals that have air-borne infection isolation (AII) wards through actual condition investigation and airflow analysis simulation (CFD) and to provide basic data for prevention. The method and scope of the study are as follows. First, through literature review, data related to prevention of infection spread in domestic medical institutions were investigated. Second, we conducted a survey on the status of isolation facilities to prevent the spread of infectious diseases in large hospitals and small and medium - sized clinics in Korea. Third, airflow analysis simulation (CFD) was carried out using the isolation ward of the nationally designated inpatient ward and the data of the plane and facility system of the small clinic. As a result of the study, it is found that regulations applicable to small and medium-sized clinics are insufficient. In addition, the simulation results show that the infectious disease virus is likely to spread to other patients in the hospital.

Inhalation Configuration Detection for COVID-19 Patient Secluded Observing using Wearable IoTs Platform

  • Sulaiman Sulmi Almutairi;Rehmat Ullah;Qazi Zia Ullah;Habib Shah
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.18 no.6
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    • pp.1478-1499
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    • 2024
  • Coronavirus disease (COVID-19) is an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. COVID-19 become an active epidemic disease due to its spread around the globe. The main causes of the spread are through interaction and transmission of the droplets through coughing and sneezing. The spread can be minimized by isolating the susceptible patients. However, it necessitates remote monitoring to check the breathing issues of the patient remotely to minimize the interactions for spread minimization. Thus, in this article, we offer a wearable-IoTs-centered framework for remote monitoring and recognition of the breathing pattern and abnormal breath detection for timely providing the proper oxygen level required. We propose wearable sensors accelerometer and gyroscope-based breathing time-series data acquisition, temporal features extraction, and machine learning algorithms for pattern detection and abnormality identification. The sensors provide the data through Bluetooth and receive it at the server for further processing and recognition. We collect the six breathing patterns from the twenty subjects and each pattern is recorded for about five minutes. We match prediction accuracies of all machine learning models under study (i.e. Random forest, Gradient boosting tree, Decision tree, and K-nearest neighbor. Our results show that normal breathing and Bradypnea are the most correctly recognized breathing patterns. However, in some cases, algorithm recognizes kussmaul well also. Collectively, the classification outcomes of Random Forest and Gradient Boost Trees are better than the other two algorithms.

Genetic relatedness of white spot syndrome virus (WSSV) from imported frozen shrimp (수입 냉동새우에서 검출된 WSSV의 유전학적 근연관계 조사)

  • Choi, So Won;Baek, Eun Jin;Choi, Ji Yeong;Tae, Won Jun;Kim, Hyoung Soon;Park, Woo Seong;Kim, Min Jae;Kim, Kwang Il
    • Journal of fish pathology
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    • v.34 no.2
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    • pp.141-147
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    • 2021
  • In this study, of the imported shrimps between 2017 and 2020, we investigated white spot syndrome virus (WSSV), covert mortality nodavirus (CMNV) and decapod iridescent virus 1 (DIV-1). Of the imported shrimps (a total of 29 groups), WSSV was detected as 31% (9/29) by nested PCR assay. And CMNV and DIV-1 were not identified in this study. To investigate the genetic relatedness of WSSV identified from imported shrimp, VR 14/15 region showed WSSV genomic variable loci was compared with reference isolates. Among the nine WSSV-positive samples, VR 14/15 region was amplified in only a sample (20-CH-1 isolate, imported from China in 2020). And the 20-CH-1 isolate showed 99.8% identity with WSSV-IN-05-01 which was reported in India in 2005, suggesting that those of WSSV have been spread from India to China. Furthermore, although the pathogenicity of WSSV identified from frozen shrimp was not evaluated, the international trade of diseased frozen shrimps could be led to the potential risk of virus transmission.

Three Cases of Kaposi's Varicelliform Eruption (Kaposi수두양 발진 3예)

  • Kim, Hyun-Sug;Hwang, Kae-Yang;Choi, Jong-Soo;Kim, Ki-Hong
    • Journal of Yeungnam Medical Science
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    • v.4 no.2
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    • pp.205-210
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    • 1987
  • Kaposi's varicelliform eruption is a more or less generalized infection of the skin, and sometimes of internal organs, with herpes simplex, vaccinia or Coxsackie virus A 16 ; it appears in people who have atopic dermatitis or some other skin diseases. There is a predilection for infants and children, but no age-group is exempt. We reported 3 cases of Kaposi's varicelliform eruption with atopic dermatitis. They had characteristic multiple umbilicated vesicles on the sites that atopic dermatitis had been involved. A 14-year-old boy and a 2-month-old infant had fever. A 17-year-old boy had wide-spread vesicles. All three patients showed multinucleated giant cells on Tzanck test, that suggests herpes simplex virus origin. They were treated with acyclovir. Within 1 to 2 days after the initiation of the therapy, new lesions had ceased to develop. Most of the lesions were cleared in 7 days without complication.

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Agroinfiltration-based Potato Virus X Replicons to Dissect the Requirements of Viral Infection

  • Park, Sang-Ho;Kim, Kook-Hyung
    • The Plant Pathology Journal
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    • v.22 no.4
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    • pp.386-390
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    • 2006
  • Extensive research of the Potato virus X(PVX) has been performed in in vitro transcription system using the bacteriophage T7 promoter. We constructed an efficient T-DNA based binary vector, pSNU1, and modified vectors carrying PVX replicons. The suitability of the construct to transiently express PVX RNA using Agrobacterium tumefaciens was tested by analysis of infectivity in plants. The expressed PVX RNA was infectous and systemically spread in three plant species including Nicotiana benthamiana, N. tabacum cv. Xanthi-nc, and Capsicum annuum cv. Chilsungcho. The PVX full length construct, pSPVXp31, was caused severe mosaic symptoms on N. benthamiana, severe necrotic lesions on C. annuum while milder symptoms and delayed mosaic symptoms were appeared on the systemic leaves on N. tabaccum. RT-PCR analysis confirmed the presence of PVX RNAs on both inoculated and systemic leaves in all three plant species tested. Our results indicated that PVX replicons were efficiently expressed PVX RNA in at least three tested species. Further investigation win be needed to elucidate the mechanism of PVX replication, translation, movement and assembly/disassembly processes.

Kushta Jast, a conventional herbo-mineral immunity booster tonic: potential use in COVID-19

  • Ahmad, Tasleem;Zakir, Mohammad;Fatma, Syeda Hajra;Kazmi, Munawwar Husain;Javed, Ghazala;Ali, Shakir
    • CELLMED
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    • v.10 no.3
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    • pp.24.1-24.6
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    • 2020
  • Kushta Jast (KJ) is a unique herbo-mineral preparation of the Unani System of Medicine (USM) which is prepared by taklis (calcination) and prescribed by the practitioners of USM for the treatment of various ailments, including the respiratory ailments. It is used as muqawwi (tonic) to boost the immunity (Muqawwi-i-badan), and can increase the phagocyte activity of the immune cells, thereby, promoting the growth and spread of lymphocytes and increasing circulating antibodies to neutralize a harmful pathogen and reduce humma or body fever (Dafi'-i-humma). Incidentally, the principal mineral component of KJ, zinc, has been widely acknowledged for its beneficial influence on the immune function, and decrease the risk of developing serious respiratory illnesses. In this manuscript, we provide a glimpse of the literature on KJ and postulate its potential beneficial effects in respiratory infections, including COVID-19.