• Title/Summary/Keyword: co-infection

Search Result 723, Processing Time 0.029 seconds

Enhancing T Cell Immune Responses by B Cell-based Therapeutic Vaccine Against Chronic Virus Infection

  • Kim, Min Ki;Lee, Ara;Hwang, Yu Kyeong;Kang, Chang-Yuil;Ha, Sang-Jun
    • IMMUNE NETWORK
    • /
    • v.14 no.4
    • /
    • pp.207-218
    • /
    • 2014
  • Chronic virus infection leads to the functional impairment of dendritic cells (DCs) as well as T cells, limiting the clinical usefulness of DC-based therapeutic vaccine against chronic virus infection. Meanwhile, B cells have been known to maintain the ability to differentiate plasma cells producing antibodies even during chronic virus infection. Previously, ${\alpha}$-galactosylceramide (${\alpha}GC$) and cognate peptide-loaded B cells were comparable to DCs in priming peptide-specific $CD8^+$ T cells as antigen presenting cells (APCs). Here, we investigated whether B cells activated by ${\alpha}GC$ can improve virus-specific T cell immune responses instead of DCs during chronic virus infection. We found that comparable to B cells isolated from naïve mice, chronic B cells isolated from chronically infected mice with lymphocytic choriomeningitis virus (LCMV) clone 13 (CL13) after ${\alpha}GC$-loading could activate CD1d-restricted invariant natural killer T (iNKT) cells to produce effector cytokines and upregulate co-stimulatory molecules in both naïve and chronically infected mice. Similar to naïve B cells, chronic B cells efficiently primed LCMV glycoprotein (GP) 33-41-specific P14 $CD8^+$ T cells in vivo, thereby allowing the proliferation of functional $CD8^+$ T cells. Importantly, when ${\alpha}GC$ and cognate epitope-loaded chronic B cells were transferred into chronically infected mice, the mice showed a significant increase in the population of epitope-specific $CD8^+$ T cells and the accelerated control of viremia. Therefore, our studies demonstrate that reciprocal activation between ${\alpha}GC$-loaded chronic B cells and iNKT cells can strengthen virus-specific T cell immune responses, providing an effective regimen of autologous B cell-based therapeutic vaccine to treat chronic virus infection.

Transcriptional Activity of Plasmodium Subtilisin-like Protease 2 (Pf-Sub2)5' Untranslated Regions and Its Interaction with Hepatocyte Growth Factor

  • Liao, Shunyao;Liu, Yunqiang;Jung, Suk-Yul;Cho, Pyo-Yun;Zheng, Bing;Park, Hyun
    • Parasites, Hosts and Diseases
    • /
    • v.48 no.4
    • /
    • pp.291-295
    • /
    • 2010
  • The onset, severity, and ultimate outcome of malaria infection are influenced by parasite-expressed virulence factors and individual host responses to these determinants, In both humans and mice, liver injury is involved after parasite entry, which persists until the erythrocyte stage after infection with the fatal strain Plasmodium falciparum (Pf), Hepatocyte growth factor (HGF) has strong anti-apoptotic effects in various kinds of cells, and also has diverse metabolic functions. In this work, Pf-subtilisin-like protease 2 (Pf-Sub2) 5' untranslated region (UTR) was analyzed and its transcriptional activity was estimated by luciferase expression. Fourteen TATA boxes were observed but only one Oct-1 and c-Myb were done. In addition, host HGF interaction with Pf-Sub2 was evaluated by co-transfection of HGF- and Pf-Sub2-cloned vector. Interestingly, -1,422/+12 UTR exhibited the strongest luciferase activity but -329 to + 12 UTR did not exhibit luciferase activity. Moreover, as compared with the control of unexpressed HGF, the HGF protein suppressed luciferase expression driven by the 5' untranslated region of the Pf-Sub2 promoter. Taken together, it is suggested that HGF controls and interacts with the promoter region of the Pf-Sub2 gene.

A Comparison of Compliance with Standard Precautions for Infection Prevention between Nurses at Accredited Korean Medicine Hospitals and Non-accredited Korean Medicine Hospitals (인증 한방병원과 비인증 한방병원 간호사의 감염예방 표준주의지침 수행도의 차이 비교)

  • Shim, Sean Ja;Park, Hyunju
    • Journal of East-West Nursing Research
    • /
    • v.28 no.2
    • /
    • pp.91-99
    • /
    • 2022
  • Purpose: The purpose of this study was to compare compliance with standard precautions of infection prevention between nurses at accredited Korean medicine hospitals and non-accredited Korean medicine hospitals. Methods: Data were collected from a total of 138 participants (69 nurses from 3 accredited hospitals and 69 nurses from 3 non-accredited hospitals) in January of 2021 using structured questionnaires. Descriptive statistics, t-test, one-way ANOVA, and multiple regression analyses were carried using the SPSS Statistics 24.0 Program. Results: Results showed that the scores of nurses' compliance with standard precautions of infection prevention at accredited Korean medicine hospital (40.54±2.74) were significantly higher (p=.002) than the scores of nurses at the non-accredited Korean medicine hospitals (38.94±3.28). After controlling for covariates, the results were same. In addition, we found that scores of compliance with standard precaution for infection prevention in nurses at hospitals belong to university were significantly high compared to those of nurses at private hospitals. We also found that the scores of compliance with standard precaution for infection prevention in nurses with more than 5 years of experience were significantly higher than those of nurses with less than 3 years of experience (p=.039). Conclusion: Nurses working at the accredited Korean medicine hospitals showed higher scores of compliance with standard precaution for infection prevention. Therefore, it is suggested that the participation in the hospital accreditation program should be encouraged for the Korean medicine hospitals.

Construction of a System for the Strawberry Nursery Production towards Elimination of Latent Infection of Anthracnose Fungi by a Combination of PCR and Microtube Hybridization

  • Furuta, Kazuyoshi;Nagashima, Saki;Inukai, Tsuyoshi;Masuta, Chikara
    • The Plant Pathology Journal
    • /
    • v.33 no.1
    • /
    • pp.80-86
    • /
    • 2017
  • One of the major problems in strawberry production is difficulty in diagnosis of anthracnose caused by Colletotrichum acutatum or Glomerella cingulata in latent infection stage. We here developed a diagnostic tool for the latent infection consisting of initial culturing of fungi, DNA extraction, synthesis of PCR-amplified probes and microtube hybridization (MTH) using a macroarray. The initial culturing step is convenient to lure the fungi out of the plant tissues, and to extract PCR-inhibitor-free DNA directly from fungal hyphae. For specific detection of the fungi, PCR primers were designed to amplify the fungal MAT1-2 gene. The subsequent MTH step using the PCR products as probes can replace the laborious electrophoresis step providing us sequence information and high-throughput screening. Using this method, we have conducted a survey for a few thousands nursery plants every year for three consecutive years, and finally succeeded in eliminating latent infection in the third year of challenge.

Risk Factors and Clinical Outcomes for Vancomycin-Resistant Enterococcus Colonization on Intensive Care Unit Admission (중환자실 환자의 입실시 반코마이신 내성 장구균 집락의 위험요인과 임상적 결과)

  • Byun, Sook-Jin;Kang, Jiyeon
    • Journal of Korean Academy of Nursing
    • /
    • v.43 no.2
    • /
    • pp.287-295
    • /
    • 2013
  • Purpose: The purpose of this study was to identify vancomycin-resistant enterococcus (VRE) colonization rate in patients admitted to the intensive care unit (ICU), associated risk factors and clinical outcomes for VRE colonization. Methods: Of the 7,703 patients admitted to the ICUs between January, 2008 and December, 2010, medical records of 554 VRE colonized and 503 uncolonized patients were reviewed retrospectively. To analyzed the impact of colonization on patients' clinical outcomes, 199 VRE colonized patients were matched with 199 uncolonized patients using a propensity score matching method. Results: During the study period, 567 (7.2%) of the 7,703 patients were colonized with VRE. Multivariate analysis identified the following independent risk factors for VRE colonization: use of antibiotics (odds ratio [OR]=3.33), having bedsores (OR=2.92), having invasive devices (OR=2.29), methicillin-resistant Staphylococcus aureus co-colonization (OR=1.84), and previous hospitalization (OR=1.74). VRE colonized patients were more likely to have infectious diseases than uncolonized patients. VRE colonization was associated with prolonged hospitalization and higher mortality. Conclusion: Strict infection control program including preemptive isolation for high-risk group may be helpful. Further research needs to be done to investigate the effects of active surveillance program on the incidence of colonization or infection with VRE in the ICU.

Immunological Mechanisms by Which Concomitant Helminth Infections Predispose to the Development of Human Tuberculosis

  • Mendez-Samperio, Patricia
    • Parasites, Hosts and Diseases
    • /
    • v.50 no.4
    • /
    • pp.281-286
    • /
    • 2012
  • Helminthic infections afflict over 1.5 billion people worldwide, while Mycobacterium tuberculosis infects one third of the world's population, resulting in 2 million deaths per year. Although tuberculosis and helminthic infections coexist in many parts of the world, and it has been demonstrated that the T-helper 2 and T-regulatory cell responses elicited by helminths can affect the ability of the host to control mycobacterial infection, it is still unclear whether helminth infections in fact affect tuberculosis disease. In this review article, current progress in the knowledge about the immunomodulation induced by helminths to diminish the protective immune responses to bacille Calmette-Guerin vaccination is reviewed, and the knowledge about the types of immune responses modulated by helminths and the consequences for tuberculosis are summarized. In addition, recent data supporting the significant reduction of both M. tuberculosis antigen-specific Toll-like receptor (TLR) 2 and TLR9 expression, and pro-inflammatory cytokine responses to TLR2 and TLR9 ligands in individuals with M. tuberculosis and helminth co-infection were discussed. This examination will allow to improve understanding of the immune responses to mycobacterial infection and also be of great relevance in combating human tuberculosis.

A Inquiry of Tracer Gas for Analysis of Dispersion and Prediction of Infection Possibility according to Airborne Viral Contaminants (건축공간에서 공기 감염균 확산을 해석하기 위한 추적가스 고찰과 농도에 따른 감염 위험성 예측 연구)

  • Lim, Tae-Seob;Kang, Seung-Mo;Kim, Byung-Seon
    • Korean Institute of Interior Design Journal
    • /
    • v.18 no.3
    • /
    • pp.102-113
    • /
    • 2009
  • The SARS virus began to appear and spread in North America and Southeast Asia in the early 2000' s, infecting and harming many people. In the process of examining the causes for the virus, studies on the airborne SARS virus and the way it spread were carried out mainly in the medical field. In the field of architecture, studies were done on the diffusion of air pollutants in buildings using gases such as $CO_2$, $N_2O$, or $SF_6$, but research on virus diffusion was limited. There were also explanations of only the diffusion process without accurate information and discussion on virus characteristics. The aim of this study is to analyze the physical characteristics of airborne virus, consider the possibility of using coupled analysis model and tracer gas for analyzing virus diffusion in building space and, based on reports of how the infection spread in a hospital where SARS patients were discovered, analyze infection risk using tracer gas density and also diffusion patterns according to the location, shape, and volume of supply diffusers and exhaust grilles. This paper can provide standards and logical principles for evaluating various alternatives for making decisions on vertical or horizontal ward placement, air supply and exhaust installation and air volumes in medium or high story medical facilities.

Light and Electron Microscopy Studies Elucidating Mechanisms of Tomato Leaf Infection by Pseudocercospora fuligena

  • Zelalem Mersha;Girma Birru;Bernhard Hau
    • The Plant Pathology Journal
    • /
    • v.39 no.2
    • /
    • pp.181-190
    • /
    • 2023
  • The fungal pathogen Pseudocercospora fuligena, known to affect tomatoes in the tropics and subtropics, has been reported from temperate climates including the United States and Turkey in recent years. In this study, an isolate from fresh tomatoes and the disease it causes were characterized and infection mechanisms investigated. Macroscopically, both sides of tomato leaves show indistinct effuse patches but prolific production of fuliginous lesions is conspicuous on the abaxial side first but also on the adaxial side later on as infection progressed. Microscopically, fascicles of conidiophores (11-128 ㎛ × 3.5-9 ㎛) arising from stromata and conidia with up to 12 septations were observed. Molecular characterization of the isolate revealed high homology (99.8%) to other P. fuligena isolated from tomatoes in Turkey. Out of the 10 media tested, P. fuligena grew significantly well and sporulated better on unsealed tomato oatmeal agar and carrot leaf decoction agar, both supplemented with CaCO3. Direct transfer of conidia from profusely sporulating lesions was the easiest and quickest method of isolation for in-vitro studies. Light and scanning electron microscopy on cleared and intact tomato leaves further confirmed stomatal penetration and egress as well as prevalence of primary and secondary infection hyphae. In situ, blocked stomatal aperture areas of 154, 401, and 2,043 ㎛2 were recorded at 7, 12, and 17 days after inoculation, respectively. With the recent expanded horizon of the pathosystem and its consequential impact, such studies will be useful for a proper diagnosis, identification and management of the disease on tomato worldwide.

Modeling Incorporating the Severity-Reducing Long-term Immunity: Higher Viral Transmission Paradoxically Reduces Severe COVID-19 During Endemic Transition

  • Hyukpyo Hong;Ji Yun Noh;Hyojung Lee;Sunhwa Choi;Boseung Choi;Jae Kyoung Kim;Eui-Cheol Shin
    • IMMUNE NETWORK
    • /
    • v.22 no.3
    • /
    • pp.23.1-23.12
    • /
    • 2022
  • Natural infection with severe acute respiratory syndrome-coronavirus-2 or vaccination induces virus-specific immunity protecting hosts from infection and severe disease. While the infection-preventing immunity gradually declines, the severity-reducing immunity is relatively well preserved. Here, based on the different longevity of these distinct immunities, we develop a mathematical model to estimate courses of endemic transition of coronavirus disease 2019 (COVID-19). Our analysis demonstrates that high viral transmission unexpectedly reduces the rates of progression to severe COVID-19 during the course of endemic transition despite increased numbers of infection cases. Our study also shows that high viral transmission amongst populations with high vaccination coverages paradoxically accelerates the endemic transition of COVID-19 with reduced numbers of severe cases. These results provide critical insights for driving public health policies in the era of 'living with COVID-19.'

Potential of Hanjeli (Coix lacryma-jobi) essential oil in preventing SARS-CoV-2 infection via blocking the Angiotensin Converting Enzyme 2 (ACE2) receptor

  • Diningrat, Diky Setya;Sari, Ayu Nirmala;Harahap, Novita Sari;Kusdianti, Kusdianti
    • Journal of Plant Biotechnology
    • /
    • v.48 no.4
    • /
    • pp.289-303
    • /
    • 2021
  • Covid-19 is an ongoing pandemic as we speak in 2022. This infectious disease is caused by the SARS-CoV-2 virus, which infects cells by binding to the angiotensin-converting enzyme 2 (ACE2) receptor on the cell surface. Thus, strategies that inhibit the binding of SARS-CoV-2 to the ACE2 receptor can stop this contagion. Hanjeli (Coix lacryma-jobi) essential oil contains many bioactive compounds, including dodecanoic acid; tetradecanoic acid; 7-Amino-8-imino-2-(2-imino-2H-chromen-3-yl); and 1,5,7,10-tetraaza-phen-9-one. These compounds suppress viral replication and may prevent Covid-19. Accordingly, this study assessed whether, these four limonoid compounds can block the ACE2 receptor. To this end, their physicochemical properties were predicted using Lipinski's "rule of five" on the SwissADME website, and their toxicity was assessed using the online tools ProTox and pkCSM. Additionally, their interactions with the ACE2 receptor were predicted via molecular docking using Autodock Vina. All the four compounds satisfied the "rule of five" and tetradecanoic acid was predicted to have a higher affinity than the comparison compound remdesivir and the original ligand of ACE2. Molecular docking results suggested that the compounds from hanjeli essential oil interact with the active site of the ACE2 receptor similarly as the original ligand and remdesivir. In conclusion, hanjeli essential oil contains compounds predicted hinder the interaction of SARS-CoV-2 with the ACE2 receptor. Accordingly, our data may facilitate the development of a phytomedical strategy against SARS-CoV-2 infection.