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1.
Appl Radiat Isot ; 156: 109010, 2020 Feb.
Article in English | MEDLINE | ID: mdl-32056690

ABSTRACT

In this study, we validated the feasibility of an energy weighted algorithm that highlights a characteristic area including the Compton edge as a single peak in a proof-of-principle radiation portal monitor system with a plastic scintillator measuring 50 × 100 × 5 cm3. We measured the energy weighted spectra with steel shielding and the dynamic movements of the 137Cs and 60Co sources. The results showed that the peak locations of each source could be identified under shielded or dynamic motion conditions, each within a maximum difference of 0.08 MeV.

2.
Exp Mol Med ; 51(12): 1-13, 2019 12 11.
Article in English | MEDLINE | ID: mdl-31827068

ABSTRACT

During viral infection, virus-derived cytosolic nucleic acids are recognized by host intracellular specific sensors. The efficacy of this recognition system is crucial for triggering innate host defenses, which then stimulate more specific adaptive immune responses against the virus. Recent studies show that signal transduction pathways activated by sensing proteins are positively or negatively regulated by many modulators to maintain host immune homeostasis. However, viruses have evolved several strategies to counteract/evade host immune reactions. These systems involve viral proteins that interact with host sensor proteins and prevent them from detecting the viral genome or from initiating immune signaling. In this review, we discuss key regulators of cytosolic sensor proteins and viral proteins based on experimental evidence.


Subject(s)
Genome, Viral/genetics , Immunity, Innate/physiology , Animals , Cytoplasm/metabolism , DEAD Box Protein 58/genetics , DEAD Box Protein 58/metabolism , Host-Pathogen Interactions , Humans , Immunity, Innate/genetics , Interferon-Induced Helicase, IFIH1/genetics , Interferon-Induced Helicase, IFIH1/metabolism , RNA Helicases/genetics , RNA Helicases/metabolism , Receptors, Immunologic , Signal Transduction/genetics , Signal Transduction/physiology
3.
PLoS Pathog ; 15(8): e1008004, 2019 08.
Article in English | MEDLINE | ID: mdl-31412082

ABSTRACT

Fas-associated factor 1 is a death-promoting protein that induces apoptosis by interacting with the Fas receptor. Until now, FAF1 was reported to interact potentially with diverse proteins and to function as a negative and/or positive regulator of several cellular possesses. However, the role of FAF1 in defense against bacterial infection remains unclear. Here, we show that FAF1 plays a pivotal role in activating NADPH oxidase in macrophages during Listeria monocytogenes infection. Upon infection by L. monocytogenes, FAF1 interacts with p67phox (an activator of the NADPH oxidase complex), thereby facilitating its stabilization and increasing the activity of NADPH oxidase. Consequently, knockdown or ectopic expression of FAF1 had a marked effect on production of ROS, proinflammatory cytokines, and antibacterial activity, in macrophages upon stimulation of TLR2 or after infection with L. monocytogenes. Consistent with this, FAF1gt/gt mice, which are knocked down in FAF1, showed weaker inflammatory responses than wild-type mice; these weaker responses led to increased replication of L. monocytogenes. Collectively, these findings suggest that FAF1 positively regulates NADPH oxidase-mediated ROS production and antibacterial defenses.


Subject(s)
Adaptor Proteins, Signal Transducing/physiology , Apoptosis Regulatory Proteins/physiology , Immunity, Innate/immunology , Inflammation/immunology , Listeriosis/immunology , Macrophages/immunology , NADPH Oxidases/metabolism , Reactive Oxygen Species/metabolism , Animals , Cytokines/metabolism , Inflammation/metabolism , Inflammation/microbiology , Listeria monocytogenes/immunology , Listeriosis/metabolism , Listeriosis/microbiology , Macrophages/metabolism , Macrophages/microbiology , Mice , Mice, Inbred C57BL , NADPH Oxidases/genetics , Phosphoproteins/genetics , Phosphoproteins/metabolism , Signal Transduction
4.
Viruses ; 11(7)2019 07 03.
Article in English | MEDLINE | ID: mdl-31277257

ABSTRACT

The herbs Plantago asiatica and Clerodendrum trichotomum have been commonly used for centuries in indigenous and folk medicine in tropical and subtropical regions of the world. In this study, we show that extracts from these herbs have antiviral effects against the respiratory syncytial virus (RSV) in vitro cell cultures and an in vivo mouse model. Treatment of HEp2 cells and A549 cells with a non-cytotoxic concentration of Plantago asiatica or Clerodendrum trichotomum extract significantly reduced RSV replication, RSV-induced cell death, RSV gene transcription, RSV protein synthesis, and also blocked syncytia formation. Interestingly, oral inoculation with each herb extract significantly improved viral clearance in the lungs of BALB/c mice. Based on reported information and a high-performance liquid chromatography (HPLC) analysis, the phenolic glycoside acteoside was identified as an active chemical component of both herb extracts. An effective dose of acteoside exhibited similar antiviral effects as each herb extract against RSV in vitro and in vivo. Collectively, these results suggest that extracts of Plantago asiatica and Clerodendrum trichotomum could provide a potent natural source of an antiviral drug candidate against RSV infection.


Subject(s)
Antiviral Agents/pharmacology , Clerodendrum/chemistry , Plant Extracts/pharmacology , Plantago/chemistry , Respiratory Syncytial Virus Infections/drug therapy , Respiratory Syncytial Viruses/drug effects , Animals , Antiviral Agents/therapeutic use , Cell Line , Disease Models, Animal , Female , Glucosides , HeLa Cells , Humans , Lung/virology , Mice , Mice, Inbred BALB C , Phenols , Plant Extracts/therapeutic use , Respiratory Syncytial Virus Infections/virology
5.
Cell Rep ; 27(7): 2105-2118.e5, 2019 05 14.
Article in English | MEDLINE | ID: mdl-31091449

ABSTRACT

Small heterodimer partner (SHP) is an orphan nuclear receptor that acts as a transcriptional co-repressor by interacting with nuclear receptors and transcription factors. Although SHP plays a negative regulatory function in various signaling pathways, its role in virus infection has not been studied. Here, we report that SHP is a potent negative regulator of the virus-mediated type I IFN signaling that maintains homeostasis within the antiviral innate immune system. Upon virus infection, SHP interacts specifically with CREB-binding protein (CBP) in the nucleus, thereby obstructing CBP/ß-catenin interaction competitively. Consequently, SHP-deficient cells enhance antiviral responses, including transcription of the type I IFN gene, upon virus infection. Furthermore, SHP-deficient mice show higher levels of IFN production and are more resistant to influenza A virus infection. Our results suggest that SHP is a nuclear regulator that blocks transcription of the type I IFN gene to inhibit excessive innate immune responses.


Subject(s)
Cell Nucleus/immunology , Immunity, Innate , Membrane Proteins/immunology , Phosphoproteins/immunology , Receptors, Cytoplasmic and Nuclear/immunology , Virus Diseases/immunology , Animals , Cell Nucleus/genetics , Cell Nucleus/virology , Membrane Proteins/genetics , Mice , Mice, Knockout , Phosphoproteins/genetics , Receptors, Cytoplasmic and Nuclear/genetics , Virus Diseases/genetics
6.
J Virol ; 93(2)2019 01 15.
Article in English | MEDLINE | ID: mdl-30355684

ABSTRACT

Tryptophanyl-tRNA synthetase (WRS) is one of the aminoacyl-tRNA synthetases (ARSs) that possesses noncanonical functions. Full-length WRS is released during bacterial infection and primes the Toll-like receptor 4 (TLR4)-myeloid differentiation factor 2 (MD2) complex to elicit innate immune responses. However, the role of WRS in viral infection remains unknown. Here, we show that full-length WRS is secreted by immune cells in the early phase of viral infection and functions as an antiviral cytokine. Treatment of cells with recombinant WRS protein promotes the production of inflammatory cytokines and type I interferons (IFNs) and curtails virus replication in THP-1 and Raw264.7 cells but not in TLR4-/- or MD2-/- bone marrow-derived macrophages (BMDMs). Intravenous and intranasal administration of recombinant WRS protein induces an innate immune response and blocks viral replication in vivo These findings suggest that secreted full-length WRS has a noncanonical role in inducing innate immune responses to viral infection as well as to bacterial infection.IMPORTANCE ARSs are essential enzymes in translation that link specific amino acids to their cognate tRNAs. In higher eukaryotes, some ARSs possess additional, noncanonical functions in the regulation of cell metabolism. Here, we report a novel noncanonical function of WRS in antiviral defense. WRS is rapidly secreted in response to viral infection and primes the innate immune response by inducing the secretion of proinflammatory cytokines and type I IFNs, resulting in the inhibition of virus replication both in vitro and in vivo Thus, we consider WRS to be a member of the antiviral innate immune response. The results of this study enhance our understanding of host defense systems and provide additional information on the noncanonical functions of ARSs.


Subject(s)
Rhabdoviridae Infections/immunology , Tryptophan-tRNA Ligase/genetics , Tryptophan-tRNA Ligase/metabolism , Vesiculovirus/pathogenicity , Administration, Intranasal , Administration, Intravenous , Animals , Cell Line , Cytokines/metabolism , HEK293 Cells , HeLa Cells , Humans , Immunity, Innate , Interferon Type I/metabolism , Mice , RAW 264.7 Cells , Rhabdoviridae Infections/genetics , THP-1 Cells , Tryptophan-tRNA Ligase/administration & dosage , Vesiculovirus/immunology
8.
Investig Clin Urol ; 59(3): 166-176, 2018 05.
Article in English | MEDLINE | ID: mdl-29744473

ABSTRACT

Purpose: Lower urinary tract symptoms (LUTS) can be distressing and socially isolating, and the economic impact can be substantial. Further data to characterize the epidemiology and effects of LUTS in South Korea would be beneficial. Materials and Methods: In an international, internet-based survey, the prevalence and impact of LUTS was evaluated in adults aged ≥40 years. Questions related to International Continence Society (ICS) symptom definitions and the bother associated with each symptom. The international prostate symptom score (IPSS) and the overactive bladder symptom score (OABSS) were assessed. Results: Of the 2,080 participants from South Korea, 1,090 (52.4%) were women and 740 (35.6%) were aged ≥60 years. The prevalence of LUTS according to ICS criteria was 68.2% (men, 70.6%; women, 66.0%). LUTS prevalence increased significantly with age (p=0.01 in men and women). Storage symptoms only were reported in 16.2% of men and 30.5% of women, making this the most common ICS symptom group overall. Individual symptoms with the highest prevalence in the overall population were nocturia, frequency, and weak stream (36%, 30%, and 29%, respectively). IPSS results showed that 40.1% of participants had at least moderate symptoms. The prevalence of OABSS-defined overactive bladder was 19.7% (men, 19.5%; women, 19.9%). Fourteen percent of individuals with any LUTS visited healthcare professionals regarding urinary symptoms. Conclusions: LUTS affect the majority of adults aged ≥40 years in South Korea. The low percentage of individuals with LUTS consulting healthcare professionals regarding urinary symptoms indicates a need to improve rates of diagnosis and treatment.


Subject(s)
Diabetes Mellitus/epidemiology , Heart Diseases/epidemiology , Hyperlipidemias/epidemiology , Hypertension/epidemiology , Lower Urinary Tract Symptoms/epidemiology , Adult , Age Factors , Aged , Aged, 80 and over , Comorbidity , Female , Health Surveys , Humans , Lower Urinary Tract Symptoms/physiopathology , Male , Middle Aged , Nervous System Diseases/epidemiology , Nocturia/epidemiology , Prevalence , Republic of Korea/epidemiology , Severity of Illness Index , Urinary Bladder, Overactive/epidemiology , Urinary Incontinence, Stress/epidemiology , Urodynamics
9.
Arch Virol ; 163(8): 2073-2083, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29619599

ABSTRACT

Enterovirus 71 (EV71) is the major causative agent of hand-foot-and-mouth disease (HFMD) and many neurological manifestations. Recently, this virus has become a serious concern because of consecutive epidemics in the Asia-Pacific region. However, no effective vaccine for EV71 has been discovered except two EV71 vaccines which are being used in local communities of China. To develop a safe and efficient EV71 vaccine candidate, we generated inactivated EV71 and evaluated its efficacy with γ-PGA/Chitosan nanoparticles (PC NPs), which are safe, biodegradable and effective as an adjuvant. The subcutaneous administration of inactivated EV71 with PC NPs adjuvant induces higher levels of virus-specific humoral (IgG, IgG1, and IgG2a) and cell-mediated immune responses (IFN-γ and IL-4). Additionally, inactivated EV71 with PC NPs adjuvant induces significantly higher virus neutralizing antibody responses compared to the virus only group, and resulted in a long lasting immunity without any noticeable side effects. Together, our findings demonstrate that PC NPs are safe and effective immunogenic adjuvants which may be promising candidates in the development of more efficacious EV71 vaccines.


Subject(s)
Enterovirus A, Human/immunology , Hand, Foot and Mouth Disease/prevention & control , Viral Vaccines/immunology , Adjuvants, Immunologic/administration & dosage , Animals , Antibodies, Neutralizing , Antibodies, Viral/immunology , Chitosan/administration & dosage , Chitosan/analogs & derivatives , Chitosan/immunology , Enterovirus A, Human/genetics , Female , Hand, Foot and Mouth Disease/immunology , Hand, Foot and Mouth Disease/virology , Humans , Immunity, Humoral , Mice , Mice, Inbred BALB C , Nanoparticles/administration & dosage , Polyglutamic Acid/administration & dosage , Polyglutamic Acid/analogs & derivatives , Polyglutamic Acid/immunology , Vaccines, Inactivated/administration & dosage , Vaccines, Inactivated/genetics , Vaccines, Inactivated/immunology , Viral Vaccines/administration & dosage , Viral Vaccines/genetics
10.
J Microbiol ; 55(11): 909-917, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29076073

ABSTRACT

Dense granule protein-7 (GRA-7) is an excretory protein of Toxoplasma gondii. It is a potential serodiagnostic marker and vaccine candidate for toxoplasmosis. Previous reports demonstrated that GRA-7 induces innate immune responses in macrophages by interacting with TRAF6 via the MyD88-dependent pathway. In the present study, we evaluated the antiviral activity and induction of an antiviral state by GRA-7 both in vitro and in vivo. It was observed that GRA-7 markedly reduced the replication of vesicular stomatitis virus (VSV-GFP), influenza A virus (PR8-GFP), coxsackievirus (H3-GFP), herpes simplex virus (HSV-GFP), and adenovirus-GFP in epithelial (HEK293T/HeLa) and immune (RAW264.7) cells. These antiviral activities of GRA-7 were attributed to the induction of type I interferon (IFN) signaling, resulting in the secretion of IFNs and pro-inflammatory cytokines. Additionally, in BALB/c mice, intranasal administration of GRA-7 prevented lethal infection by influenza A virus (H1N1) and exhibited prophylactic effects against respiratory syncytial virus (RSV-GFP). Collectively, these results suggested that GRA-7 exhibits immunostimulatory and broad spectrum antiviral activities via type I IFN signaling. Thus, GRA-7 can be potentially used as a vaccine adjuvant or as a candidate drug with prophylactic potential against viruses.


Subject(s)
Protozoan Proteins/pharmacology , Toxoplasma/chemistry , Virus Replication/drug effects , Viruses/drug effects , Animals , Antiviral Agents/administration & dosage , Antiviral Agents/pharmacology , Cytokines , Enterovirus/drug effects , Female , HEK293 Cells , HeLa Cells , Humans , Influenza A Virus, H1N1 Subtype/drug effects , Influenza A virus/drug effects , Influenza, Human/drug therapy , Influenza, Human/virology , Interferon Type I/immunology , Mice , Mice, Inbred BALB C , Orthomyxoviridae Infections/drug therapy , Orthomyxoviridae Infections/prevention & control , Orthomyxoviridae Infections/virology , Protozoan Proteins/isolation & purification , Respiratory Syncytial Virus Infections/prevention & control , Respiratory Syncytial Virus Infections/virology , Simplexvirus/drug effects , Vesiculovirus/drug effects , Virus Diseases/prevention & control , Virus Diseases/virology
11.
Sci Rep ; 7(1): 4875, 2017 07 07.
Article in English | MEDLINE | ID: mdl-28687749

ABSTRACT

The antiviral activities of synthesized Kα2-helix peptide, which was derived from the viral FLICE-like inhibitor protein (vFLIP) of Kaposi's sarcoma-associated herpesvirus (KSHV), against influenza A virus (IAV) were investigated in vitro and in vivo, and mechanisms of action were suggested. In addition to the robust autophagy activity of the Kα2-helix peptide, the present study showed that treatment with the Kα2 peptide fused with the TAT peptide significantly inhibited IAV replication and transmission. Moreover, TAT-Kα2 peptide protected the mice, that were challenged with lethal doses of highly pathogenic influenza A H5N1 or H1N1 viruses. Mechanistically, we found that TAT-Kα2 peptide destabilized the viral membranes, depending on their lipid composition of the viral envelop. In addition to IAV, the Kα2 peptide inhibited infections with enveloped viruses, such as Vesicular Stomatitis Virus (VSV) and Respiratory Syncytial Virus (RSV), without cytotoxicity. These results suggest that TAT-Kα2 peptide is a potential antiviral agent for controlling emerging or re-emerging enveloped viruses, particularly diverse subtypes of IAVs.


Subject(s)
Antiviral Agents/metabolism , Influenza A virus/drug effects , Oligopeptides/metabolism , Viral Proteins/metabolism , Virus Replication/drug effects , Animals , Antiviral Agents/isolation & purification , Disease Models, Animal , Dogs , Influenza A virus/physiology , Lung/virology , Madin Darby Canine Kidney Cells , Mice, Inbred BALB C , Oligopeptides/isolation & purification , Orthomyxoviridae Infections/pathology , Orthomyxoviridae Infections/prevention & control , Respiratory Syncytial Viruses/drug effects , Respiratory Syncytial Viruses/physiology , Survival Analysis , Treatment Outcome , Vesiculovirus/drug effects , Vesiculovirus/physiology , Viral Load , Virus Internalization/drug effects , Virus Release/drug effects
12.
PLoS Pathog ; 13(5): e1006398, 2017 May.
Article in English | MEDLINE | ID: mdl-28542569

ABSTRACT

FAS-associated factor-1 (FAF1) is a component of the death-inducing signaling complex involved in Fas-mediated apoptosis. It regulates NF-κB activity, ubiquitination, and proteasomal degradation. Here, we found that FAF1 positively regulates the type I interferon pathway. FAF1gt/gt mice, which deficient in FAF1, and FAF1 knockdown immune cells were highly susceptible to RNA virus infection and showed low levels of inflammatory cytokines and type I interferon (IFN) production. FAF1 was bound competitively to NLRX1 and positively regulated type I IFN signaling by interfering with the interaction between NLRX1 and MAVS, thereby freeing MAVS to bind RIG-I, which switched on the MAVS-RIG-I-mediated antiviral signaling cascade. These results highlight a critical role of FAF1 in antiviral responses against RNA virus infection.


Subject(s)
Carrier Proteins/immunology , Interferon Type I/immunology , RNA Virus Infections/immunology , RNA Viruses/physiology , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/immunology , Animals , Apoptosis Regulatory Proteins , Carrier Proteins/genetics , Female , Humans , Interferon Type I/genetics , Intracellular Signaling Peptides and Proteins , Macrophages/immunology , Macrophages/virology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Mitochondrial Proteins/genetics , Mitochondrial Proteins/immunology , NF-kappa B/genetics , NF-kappa B/immunology , RNA Virus Infections/genetics , RNA Virus Infections/virology
13.
J Virol ; 91(14)2017 07 15.
Article in English | MEDLINE | ID: mdl-28468885

ABSTRACT

Rubicon is part of a Beclin-1-Vps34-containing autophagy complex. Rubicon induces antimicrobial responses upon Toll-like receptor (TLR) stimulation and functions as a feedback inhibitor to prevent unbalanced proinflammatory responses depending on dectin-1 signaling. However, the role played by Rubicon during antiviral immune responses, particularly the type I interferon (IFN) responses, remains largely unknown. Here, we report that Rubicon acts as a negative regulator for virus-triggered IFN signaling. Knockdown of Rubicon promoted type I interferon signaling and inhibited virus replication, while overexpression of Rubicon had the opposite effect. Rubicon specifically interacts with the interferon regulatory factor (IRF) association domain (IAD) of IRF3, and this interaction leads to inhibition of the dimerization of IRF3, which negatively regulates IFN-mediated antiviral response. Thus, our findings suggest the novel additional role of Rubicon as a negative regulator that inhibits the IFN signaling and cellular antiviral responses, providing a novel cellular mechanism of IRF3 inhibition.IMPORTANCE The type I IFN system is a critical innate immune response that protects organisms against virus infection. However, type I IFN signaling must be tightly regulated to avoid excessive production of IFNs. Hence, negative regulatory mechanisms for type I IFN signaling are important, and to date, several related molecules have been identified. Here, we show that Rubicon is a major negative regulator of type I IFN signaling, and unlike previous reports of cellular molecules that inhibit IRF3 activation via proteasomal degradation or dephosphorylation of IRF3, we show that Rubicon interacts with IRF3 and that ultimately this interaction leads to inhibition of the dimerization of IRF3. Thus, we identified a novel negative regulator of type I IFN signaling pathways and a novel cellular mechanism of IRF3 inhibition. The results of this study will increase our understanding of the role of negative-feedback mechanisms that regulate type I IFN signaling and maintain immune homeostasis.


Subject(s)
Influenza A Virus, H1N1 Subtype/immunology , Interferon Regulatory Factor-3/metabolism , Interferon Type I/antagonists & inhibitors , Intracellular Signaling Peptides and Proteins/metabolism , Protein Multimerization , Signal Transduction , Vesiculovirus/immunology , Animals , Mice , RAW 264.7 Cells
14.
Thorac Cancer ; 8(3): 251-259, 2017 05.
Article in English | MEDLINE | ID: mdl-28371058

ABSTRACT

BACKGROUND: This multicenter study was performed to develop a prognosis-prediction model incorporating genetic polymorphism with pathologic stage for surgically treated non-small cell lung cancer (NSCLC) patients. METHODS: A replication study including 720 patients and a panel of eight single nucleotide polymorphisms (SNPs), which predicted the prognosis of surgically treated NSCLC in our previous study, was conducted. Using the combined cohort of current and previous studies including 1534 patients, a nomogram for predicting overall survival was made using Cox proportional hazards regression. RESULTS: Among the eight SNPs, C3 rs2287845, GNB2L1 (alias RACK1), and rs3756585 were significantly associated with overall survival. A nomogram was constructed based on pathologic stage and the genotypes of the two SNPs, and the risk score was calculated for each patient in the combined cohort. Using the prognosis-prediction model, we categorized patients into low, intermediate, and high-risk groups, which had greater accuracy in predictive ability (log-rank statistics = 54.66) than the conventional tumor node metastasis staging (log-rank statistics = 39.56). Next, we generated a prognosis-prediction model for stage I to identify a subgroup of potential candidates for adjuvant chemotherapy. Notably, 97 out of 499 stage IB patients were classified as high-risk patients with a similar prognosis to stage II patients, suggesting the benefit of adjuvant chemotherapy. CONCLUSIONS: This prognosis-prediction model incorporating genetic polymorphism with pathologic stage may lead to more precise prognostication in surgically resected NSCLC patients. In particular, this model may be useful in selecting a subgroup of stage IB patients who may benefit from adjuvant chemotherapy.


Subject(s)
Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Prognosis , Adult , Aged , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/surgery , Chemotherapy, Adjuvant , Disease-Free Survival , Genotype , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Neoplasm Staging , Polymorphism, Single Nucleotide , Risk Factors
15.
Med Phys ; 44(5): 1734-1746, 2017 May.
Article in English | MEDLINE | ID: mdl-28273345

ABSTRACT

PURPOSE: While positron emission tomography (PET) allows for the imaging of tissues activated by proton beams in terms of monitoring the therapy administered, most endogenous tissue elements are activated by relatively high-energy protons. Therefore, a relatively large distance off-set exists between the dose fall-off and activity fall-off. However, 16 O(p,2p,2n)13 N has a relatively low energy threshold which peaks around 12 MeV and also a residual proton range that is approximately 1 to 2 mm. In this phantom study, we tested the feasibility of utilizing the 13 N production peak as well as the differences in activity fall-off between early and late PET scans for proton range verification. One of the main purposes for this research was developing a proton range verification methodology that would not require Monte Carlo simulations. METHODS AND MATERIALS: Both monoenergetic and spread-out Bragg peak beams were delivered to two phantoms - a water-like gel and a tissue-like gel where the proton ranges came to be approximately 9.9 and 9.1 cm, respectively. After 1 min of postirradiation delay, the phantoms were scanned for a period of 30 min using an in-room PET. Two separate (Early and Late) PET images were reconstructed using two different postirradiation delays and acquisition times; Early PET: 1 min delay and 3 min acquisition, Late PET: 21 min delay and 10 min acquisition. The depth gradients of the PET signals were then normalized and plotted as functions of depth. The normalized gradient of the early PET images was subtracted from that of the late PET images, to observe the 13 N activity distribution in relation to depth. Monte Carlo simulations were also conducted with the same set-up as the measurements stated previously. RESULTS: The subtracted gradients show peaks at 9.4 and 8.6 cm in water-gel and tissue-gel respectively for both pristine and SOBP beams. These peaks are created in connection with the sudden change of 13 N signals with depth and consistently occur 2 mm upstream to where 13 N signals were most abundantly created (9.6 and 8.8 cm in water-gel and tissue-gel, respectively). Monte Carlo simulations provided similar results as the measurements. CONCLUSIONS: The subtracted PET signal gradient peaks and the proton ranges for water-gel and tissue-gel show distance off-sets of 4 to 5 mm. This off-set may potentially be used for proton range verification using only the PET measured data without Monte Carlo simulations. More studies are necessary to overcome various limitations, such as perfusion-driven washout, for the feasibility of this technique in living patients.


Subject(s)
Phantoms, Imaging , Positron-Emission Tomography , Protons , Feasibility Studies , Humans , Monte Carlo Method
17.
J Microbiol ; 54(12): 853-866, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27888461

ABSTRACT

Bee venom (BV) from honey bee (Apis Melifera L.) contains at least 18 pharmacologically active components including melittin (MLT), phospholipase A2 (PLA2), and apamin etc. BV is safe for human treatments dose dependently and proven to possess different healing properties including antibacterial and antiparasitidal properties. Nevertheless, antiviral properties of BV have not well investigated. Hence, we identified the potential antiviral properties of BV and its component against a broad panel of viruses. Co-incubation of non-cytotoxic amounts of BV and MLT, the main component of BV, significantly inhibited the replication of enveloped viruses such as Influenza A virus (PR8), Vesicular Stomatitis Virus (VSV), Respiratory Syncytial Virus (RSV), and Herpes Simplex Virus (HSV). Additionally, BV and MLT also inhibited the replication of non-enveloped viruses such as Enterovirus-71 (EV-71) and Coxsackie Virus (H3). Such antiviral properties were mainly explained by virucidal mechanism. Moreover, MLT protected mice which were challenged with lethal doses of pathogenic influenza A H1N1 viruses. Therefore, these results provides the evidence that BV and MLT could be a potential source as a promising antiviral agent, especially to develop as a broad spectrum antiviral agent.


Subject(s)
Antiviral Agents/pharmacology , Bee Venoms/pharmacology , Orthomyxoviridae Infections/drug therapy , Viruses/drug effects , Animals , Antiviral Agents/administration & dosage , Antiviral Agents/chemistry , Apamin/chemistry , Bee Venoms/administration & dosage , Bee Venoms/chemistry , Cell Line , Enterovirus/drug effects , Influenza A Virus, H1N1 Subtype/drug effects , Influenza A Virus, H1N1 Subtype/physiology , Influenza A virus/drug effects , Melitten/pharmacology , Mice , Orthomyxoviridae Infections/virology , Simplexvirus/drug effects , Virus Replication/drug effects
18.
Nat Immunol ; 17(11): 1252-1262, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27595231

ABSTRACT

The mammalian cytoplasmic multi-tRNA synthetase complex (MSC) is a depot system that regulates non-translational cellular functions. Here we found that the MSC component glutamyl-prolyl-tRNA synthetase (EPRS) switched its function following viral infection and exhibited potent antiviral activity. Infection-specific phosphorylation of EPRS at Ser990 induced its dissociation from the MSC, after which it was guided to the antiviral signaling pathway, where it interacted with PCBP2, a negative regulator of mitochondrial antiviral signaling protein (MAVS) that is critical for antiviral immunity. This interaction blocked PCBP2-mediated ubiquitination of MAVS and ultimately suppressed viral replication. EPRS-haploid (Eprs+/-) mice showed enhanced viremia and inflammation and delayed viral clearance. This stimulus-inducible activation of MAVS by EPRS suggests an unexpected role for the MSC as a regulator of immune responses to viral infection.


Subject(s)
Amino Acyl-tRNA Synthetases/metabolism , Disease Resistance/immunology , Host-Pathogen Interactions/immunology , Virus Diseases/immunology , Virus Diseases/metabolism , Amino Acyl-tRNA Synthetases/chemistry , Amino Acyl-tRNA Synthetases/genetics , Animals , Antiviral Agents/pharmacology , Disease Models, Animal , Immunity, Innate , Mice , Mice, Knockout , Peptides/pharmacology , Phosphorylation , Protein Binding , RNA Virus Infections/immunology , RNA Virus Infections/metabolism , RNA Virus Infections/virology , RNA Viruses/drug effects , RNA Viruses/immunology , RNA-Binding Proteins/metabolism , Signal Transduction , Ubiquitination , Virus Diseases/virology , Virus Replication
19.
Appl Radiat Isot ; 118: 56-61, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27611081

ABSTRACT

The aim of this study is to develop the assessment technique of the effective dose by calculating the organ equivalent dose with a Monte Carlo (MC) simulation and a computational human phantom for the naturally occurring radioactive material (NORM) added consumer products. In this study, we suggests the method determining the MC source term based on the skin-point source enabling the convenient and conservative modeling of the various type of the products. To validate the skin-point source method, the organ equivalent doses were compared with that by the product modeling source of the realistic shape for the pillow, waist supporter, sleeping mattress etc. Our results show that according to the source location, the organ equivalent doses were observed as the similar tendency for both source determining methods, however, it was observed that the annual effective dose with the skin-point source was conservative than that with the modeling source with the maximum 3.3 times higher dose. With the assumption of the gamma energy of 1MeV and product activity of 1Bqg-1, the annual effective doses of the pillow, waist supporter and sleeping mattress with skin-point source was 3.09E-16SvBq-1year-1, 1.45E-15SvBq-1year-1, and 2,82E-16SvBq-1year-1, respectively, while the product modeling source showed 9.22E-17SvBq-1year-1, 9.29E-16SvBq-1year-1, and 8.83E-17SvBq-1year-1, respectively. In conclusion, it was demonstrated in this study that the skin-point source method could be employed to efficiently evaluate the annual effective dose due to the usage of the NORM added consumer products.


Subject(s)
Household Products/analysis , Models, Biological , Monte Carlo Method , Radiation Exposure/analysis , Skin Physiological Phenomena , Viscera/physiology , Whole-Body Counting/methods , Computer Simulation , Consumer Product Safety , Finite Element Analysis , Humans , Organ Specificity/physiology , Phantoms, Imaging , Radiation Dosage , Reproducibility of Results , Scattering, Radiation , Sensitivity and Specificity
20.
Appl Radiat Isot ; 110: 230-235, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26778449

ABSTRACT

The aim of this study is to evaluate the potential hazard of naturally occurring radioactive material (NORM) added consumer products. Using the Monte Carlo method, the radioactive products were simulated with ICRP reference phantom and the organ doses were calculated with the usage scenario. Finally, the annual effective doses were evaluated as lower than the public dose limit of 1mSv y(-1) for 44 products. It was demonstrated that NORM-added consumer products could be quantitatively assessed for the safety regulation.


Subject(s)
Consumer Product Safety , Radioisotopes/analysis , Female , Household Articles , Household Products/adverse effects , Household Products/analysis , Humans , Male , Monte Carlo Method , Phantoms, Imaging , Radiation Dosage , Radiation Exposure , Radioisotopes/adverse effects
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