• Title/Summary/Keyword: Persistent Infection

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Reovirus and Tumor Oncolysis

  • Kim, Man-Bok;Chung, Young-Hwa;Johnston, Randal N.
    • Journal of Microbiology
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    • v.45 no.3
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    • pp.187-192
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    • 2007
  • REOviruses (Respiratory Enteric Orphan viruses) are ubiquitous, non-enveloped viruses containing 10 segments of double-stranded RNA (dsRNA) as their genome. They are common isolates of the respiratory and gastrointestinal tract of humans but are not associated with severe disease and are therefore considered relatively benign. An intriguing characteristic of reovirus is its innate oncolytic potential, which is linked to the transformed state of the cell. When immortalized cells are transfected in vitro with activated oncogenes such as Ras, Sos, v-erbB, or c-myc, they became susceptible to reovirus infection and subsequent cellular lysis, indicating that oncogene signaling pathways are exploited by reovirus. This observation has led to the use of the virus in clinical trials as an anti-cancer agent against oncogenic tumors. In addition to the exploitation of oncogene signaling, reovirus may further utilize host immune responses to enhance its antitumor activity in vivo due to its innate interferon induction ability. Reovirus is, however, not entirely benign to immunocompromised animal models. Reovirus causes so-called "black feet syndrome" in immunodeficient mice and can also harm neonatal animals. Because cancer patients often undergo immunosuppression due to heavy chemo/radiation-treatments or advanced tumor progression, this pathogenic response may be a hurdle in virus-based anticancer therapies. However, a genetically attenuated reovirus variant derived from persistent reovirus infection of cells in vitro is able to exert potent anti-tumor activity with significantly reduced viral pathogenesis in immunocompromised animals. Importantly, in this instance the attenuated, reovirus maintains its oncolytic potential while significantly reducing viral pathogenesis in vivo.

Hepatitis C Virus Nonstructural Protein 5A Interacts with Immunomodulatory Kinase IKKε to Negatively Regulate Innate Antiviral Immunity

  • Kang, Sang-Min;Park, Ji-Young;Han, Hee-Jeong;Song, Byeong-Min;Tark, Dongseob;Choi, Byeong-Sun;Hwang, Soon B.
    • Molecules and Cells
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    • v.45 no.10
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    • pp.702-717
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    • 2022
  • Hepatitis C virus (HCV) infection can lead to chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. HCV employs diverse strategies to evade host antiviral innate immune responses to mediate a persistent infection. In the present study, we show that nonstructural protein 5A (NS5A) interacts with an NF-κB inhibitor immunomodulatory kinase, IKKε, and subsequently downregulates beta interferon (IFN-β) promoter activity. We further demonstrate that NS5A inhibits DDX3-mediated IKKε and interferon regulatory factor 3 (IRF3) phosphorylation. We also note that hyperphosphorylation of NS5A mediates protein interplay between NS5A and IKKε, thereby contributing to NS5A mediated modulation of IFN-β signaling. Lastly, NS5A inhibits IKKε-dependent p65 phosphorylation and NF-κB activation. Based on these findings, we propose NS5A as a novel regulator of IFN signaling events, specifically by inhibiting IKKε downstream signaling cascades through its interaction with IKKε. Taken together, these data suggest an additional mechanistic means by which HCV modulates host antiviral innate immune responses to promote persistent viral infection.

Anterior Sagittal Transrectal Approach (ASTRA) for Urethrovaginal Fistula after Total Repair of Persistent Cloaca - 1 Case Report - (잔존 총배설강 기형 수술 후 발생한 요도-질 누공에 대한 전방 시상 경직장적 접근 술식 (Anterior Sagittal Transrectal Approach, ASTRA) 1 례보고)

  • Kim, Seong-Min;Kim, Chang-Woo;Kim, Byoung-Kyu;Oh, Jung-Tak;Han, Seok-Joo
    • Advances in pediatric surgery
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    • v.13 no.1
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    • pp.76-80
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    • 2007
  • The authors applied anterior sagittal transrectal apporach (ASTRA) for the repair of urethrovaginal fistula which developed after total repair of persistent cloaca. The patient had been diagnosed to have persistent cloaca, double uterus and double vagina, and received PSARP, excision of right-side uterus and vagina, and left vaginal switch operation at 22 months old. After operation, the patient admitted several times due to frequent urinary tract infection and ectopic stone formation in bladder and neovagina. Urethro-neovaginal fistula was confirmed by cystoscopy and corrected with ASTRA. Postoperative voiding cystourethrogram showed no fistula tract. ASTRA showed improved surgical field, minimized ureterocystic damage, and preserved perirectal nerve due to limited incision of rectum.

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Retrospective Study for Morbidity and Mortality after Major Lung Resection (폐절제술후 발생한 합병증 및 사망률에 대한 후향적 고찰)

  • Moon, Kwang-Deok;Lee, Cheol-Joo;Kim, Young-Jin;Choi, Ho;Kim, Jung-Tae;Kang, Joon-Kyu;Hong, Joon-Hwa
    • Journal of Chest Surgery
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    • v.33 no.4
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    • pp.310-315
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    • 2000
  • Background: A retrospectiye study was done for understanding morbidity and mortality after major lung resection. Material and Method: From June 1994 to August 1998, 203 patients received major lung resections for various causes. There were 142 males and 62 females with a mean age of 47.5 years. Initial complains were cough in 47.8%, sputum in 33.0%, hemoptysis or blood-tinged sputum in 23.2%, dyspnea in 18.2%, chest pain in 15.3%, weight loss in 10.8%, fever and chill in 4.9%. There were no complaints in 5.9% of the total patients. The underlying diseases were lung tumor(102 cases/50.2%), bronchectasis(28 cases/13.8%), aspergillosis(24 cases/1.8%), tuberculosis(20 cases/9.9%) and others (29 cases/66.5%) and pneumonectomy(68 cases/33.5%). The postoperative complications were classified as : empyema, BPF, respiratory problem, persistent air leakage over 7 days, arrhythmia, ventilator applied over 24 hours, bleeding, wound infection and chylothorax. The postlobectomy complications were revealed as follow: empyema(3.7%), BPF(2.2%), respiratory problem(5.2%), persistent air leakage over 7days(8.9%), arrhythmia(2.2%), ventilator applied over 24 hours(2.2%), bleeding(1.5%), wound infection(2.9%), chylothorax(0.7%). The postpneumonectomy complications were revealed as follow : empyema(5.9%), BPF (5.9%), respiratory problem(17.6%), persistent air leakage over 7days(0%), arrhythmia(5.4%), ventialtor apply over 24 hours(7.4%), bleeding (7.4%), wound infection(2.9%) and chylothorax(1.5%). Reoperation was done in 8 cases (4.0%). There were 5.8% operative mortalities in pneumonectomy and 0.7% in lobectomy.

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Risk factors for persistent otitis media with effusion in children: a case-control study

  • Lee, Ju Yeon;Kim, Se-Hyung;Song, Chan Il;Kim, Young Ree;Kim, Yoon-Joo;Choi, Jae Hong
    • Journal of Yeungnam Medical Science
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    • v.35 no.1
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    • pp.70-75
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    • 2018
  • Background: Otitis media with effusion (OME) is defined as middle ear effusion without acute signs of infection. OME usually resolves spontaneously; however, persistent OME may require the insertion of a ventilation tube. This study investigated risk factors for persistent OME in children who undergo ventilation tube insertion. Methods: Children who were admitted to undergo ventilation tube insertion at Jeju National University Hospital between August 2015 and July 2016 were enrolled as the case group. Healthy children without persistent OME from August 2016 to July 2017 were enrolled as the control group. Baseline characteristics and predisposing factor data were collected using an interview questionnaire. Middle ear fluids were collected from the case group. Results: A total of 31 patients underwent ventilation tube insertion. The mean age of the case group was 4.53 years, with a male-to-female ratio of 21:10. Twenty-nine (93.5%) children attended a daycare center, and 21 (67.7%) had experience with bottle feeding. Fifteen (48.4%) children in the case group and 3 (9.7%) in the control group first attended a daycare center at <1 year of age (odds ratio=9.96; 95% confidence interval=2.44-39.70; p=0.001). No bacteria were found in middle ear fluid collected from the 31 operated children. Nasopharyngeal bacterial colonization was found in 13 (41.9%) and 17 (54.8%) children in the case and control groups, respectively. Conclusion: Earlier attendance at a daycare center was the only predisposing factor for ventilation tube insertion in our study. The aseptic nature of middle ear fluids found in children with OME highlights the efficacy of antimicrobial use.

Measles Viral Infection in PD-1 Gene Knockout Mice (PD-1 유전자 제거 마우스에서 홍역바이러스 감염)

  • Chun, Jin Kyong;Kim, Kyu Yeun;Hur, Ji Ae;Kang, Dong Won;Kim, Ki Hwan;Kim, Dong Soo
    • Pediatric Infection and Vaccine
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    • v.20 no.3
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    • pp.123-130
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    • 2013
  • Purpose: Subacute sclerosing panencephalitis (SSPE) is a neurodegerative disease due to persistent measles virus infection. We investigated the role of programmed death-1 (PD-1) molecule which is related with chronic viral infection in developing SSPE in mouse. Methods: We adopt the $PD-1^{-/-}$, $PD-1^{-/+}$, and wild type BALB/c 3 week old mice to make an animal model of SSPE by injecting measles virus (SSPE strain) intraventricularly. Three months after infusion of virus, the mice were sacrificed and examined if the typical pathologic lesions had been progressed. The sera were collected from each group of mice and the serum level of IL-21 was measured with ELISA kit. Results: The necrotic lesions on white matter and gliosis were found in focal areas in wild type BALB/c. The extent of lesion was smaller in heterotype BALB/c. Scanty lesions were found in $PD-1^{-/-}$ mice. The sera level of IL-21 was not elevated in all three groups. Conclusion: Our data suggest that the PD-1 molecule may play a role in persistent viral infection.

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Microbial etiology of endodontic treatment failure

  • Kum, Kee-Yeon
    • Proceedings of the KACD Conference
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    • 2003.11a
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    • pp.606-606
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    • 2003
  • There have been many studies that have evaluated success and failure of endodontic treatment (Nair, Sjogren), but there is remarkably limited information concerning the specific microorganisms that are involved in the teeth with treatment failure. Microorganisms that survive root canal treatment to cause a persistent infection must possess specific characteristics to avoid the host defense. These can be broadly classified as; 1. Sequestration:A physical barrier between the microbe and the host. 2. Cellular evasion:Microorganisms avoid leukocyte dependent antibacterial mechanisms. 3. Humoral evasion:Extracellular bacteria avoid the hosts antibodies and complement.(omitted)

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Serological evidence on the persistence of porcine epidemic diarrhea virus infection (돼지 유행성 설사병(porcine epidemic diarrhea)의 상재화에 대한 혈청학적 증명)

  • Park, Bong-kyun;Han, Kyung-soo;Lyoo, Kwang-soo;Kim, Jun-young;Jeong, Hyun-kyu
    • Korean Journal of Veterinary Research
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    • v.38 no.4
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    • pp.818-822
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    • 1998
  • The persistence of porcine epidemic diarrhea virus(PEDV) infection was demonstrated in 7 swine farms employing continuous pig flow management even after seasonal outbreaks. Clinically, sporadic postweaning diarrhea was a major concern in those farms. Subsequently circulatory antibody detection using serum neutralizing test made useful for confirmation of PEDV persistent infections. The persistence of PEDV in the premise might have induced recurrence over the period of time.

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Alcohol Induced Hepatic Degeneration of HCV-Tg Mouse

  • Noh, Dong-hyung;Yu, Dae-yeul;Jeong, Kyu-shik
    • Proceedings of the Korean Society of Veterinary Pathology Conference
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    • 2003.10a
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    • pp.18-18
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    • 2003
  • Hepatitis C virus (HCV) has become a major public health issue and is prevalent in most countries. HCV infection starts frequently without clinical symptoms, and progresses in the majority of patients (70 to 85%) to persistent viremia and chronic hepatitis including cirrhosis and hepatocellularcarcinoma (HCC) [1]. Alcohol is one of the independent cofactors accelerating the development of HCC in chronic hepatitis C patients. This is of great interest because a synergy between excessive alcohol intake and HCV infection has been documented in the development of HCC in chronic hepatitis C patients [2]. The aim of this study is to investigate liver changes in ethanol feeding HCV-transgenic (Tg) mouse and to establish an animal model system. (omitted)

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Essential of Endodontic microsurgery with the use of a Surgical Operating Microscope (외과적 근관치료의 핵심 - 치근단 미세누출 폐쇄술)

  • Kim, Sunil
    • The Journal of the Korean dental association
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    • v.55 no.8
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    • pp.556-564
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    • 2017
  • Endodontic surgery is a procedure to treat apical periodontitis or abscess in cases that did not heal after nonsurgical treatment or retreatment. This might include situations with persistent intracanal infection after root canal treatment. Other reasons might be found in extraradicular infection, such as bacterial biofilm on the apical root surface or bacteria within the lesion. For many years, the treatment standard was the traditional approach with surgical burs and amalgam for root-end filling. Endodontic microsurgery is the most recent step in the evolution of endodontic surgery, applying not only ultrasonic tip and biocompatible filling materials but also incorporating high-power magnification and illumination. Although many studies have been published that advocate the use of modern technique, the traditional techniques are still widely used in the surgery community. The purpose of this study was to demonstrate the endodontic microsurgery procedure including the root-end preparation and filling with the use of a surgical operating microscope.

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