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Replicative capacity of SARS-CoV-2 omicron variants BA.5 and BQ.1.1 at elevated temperatures. THE LANCET. MICROBE 2023; 4:e486. [PMID: 37105204 PMCID: PMC10124997 DOI: 10.1016/s2666-5247(23)00100-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 03/07/2023] [Indexed: 04/29/2023]
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2
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Cryoelectron microscopic structure of the nucleoprotein-RNA complex of the European filovirus, Lloviu virus. PNAS NEXUS 2023; 2:pgad120. [PMID: 37124400 PMCID: PMC10139700 DOI: 10.1093/pnasnexus/pgad120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 03/17/2023] [Accepted: 03/27/2023] [Indexed: 05/02/2023]
Abstract
Lloviu virus (LLOV) is a novel filovirus detected in Schreiber's bats in Europe. The isolation of the infectious LLOV from bats has raised public health concerns. However, the virological and molecular characteristics of LLOV remain largely unknown. The nucleoprotein (NP) of LLOV encapsidates the viral genomic RNA to form a helical NP-RNA complex, which acts as a scaffold for nucleocapsid formation and de novo viral RNA synthesis. In this study, using single-particle cryoelectron microscopy, we determined two structures of the LLOV NP-RNA helical complex, comprising a full-length and a C-terminally truncated NP. The two helical structures were identical, demonstrating that the N-terminal region determines the helical arrangement of the NP. The LLOV NP-RNA protomers displayed a structure similar to that in the Ebola and Marburg virus, but the spatial arrangements in the helix differed. Structure-based mutational analysis identified amino acids involved in the helical assembly and viral RNA synthesis. These structures advance our understanding of the filovirus nucleocapsid formation and provide a structural basis for the development of antifiloviral therapeutics.
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A circulating subset of iNKT cells mediates antitumor and antiviral immunity. Sci Immunol 2022; 7:eabj8760. [DOI: 10.1126/sciimmunol.abj8760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Invariant natural killer T (iNKT) cells are a group of innate-like T lymphocytes that recognize lipid antigens. They are supposed to be tissue resident and important for systemic and local immune regulation. To investigate the heterogeneity of iNKT cells, we recharacterized iNKT cells in the thymus and peripheral tissues. iNKT cells in the thymus were divided into three subpopulations by the expression of the natural killer cell receptor CD244 and the chemokine receptor CXCR6 and designated as C0 (CD244
−
CXCR6
−
), C1 (CD244
−
CXCR6
+
), or C2 (CD244
+
CXCR6
+
) iNKT cells. The development and maturation of C2 iNKT cells from C0 iNKT cells strictly depended on IL-15 produced by thymic epithelial cells. C2 iNKT cells expressed high levels of IFN-γ and granzymes and exhibited more NK cell–like features, whereas C1 iNKT cells showed more T cell–like characteristics. C2 iNKT cells were influenced by the microbiome and aging and suppressed the expression of the autoimmune regulator AIRE in the thymus. In peripheral tissues, C2 iNKT cells were circulating that were distinct from conventional tissue-resident C1 iNKT cells. Functionally, C2 iNKT cells protected mice from the tumor metastasis of melanoma cells by enhancing antitumor immunity and promoted antiviral immune responses against influenza virus infection. Furthermore, we identified human CD244
+
CXCR6
+
iNKT cells with high cytotoxic properties as a counterpart of mouse C2 iNKT cells. Thus, this study reveals a circulating subset of iNKT cells with NK cell–like properties distinct from conventional tissue-resident iNKT cells.
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Abstract
The development of an in vitro cell model that can be used to study severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) research is expected. Here we conducted infection experiments in bronchial organoids (BO) and an BO-derived air-liquid interface model (BO-ALI) using 8 SARS-CoV-2 variants. The infection efficiency in BO-ALI was more than 1,000 times higher than that in BO. Among the bronchial epithelial cells, we found that ciliated cells were infected with the virus, but basal cells were not. Ciliated cells died 7 days after the viral infection, but basal cells survived after the viral infection and differentiated into ciliated cells. Fibroblast growth factor 10 signaling was essential for this differentiation. These results indicate that BO and BO-ALI may be used not only to evaluate the cell response to SARS-CoV-2 and coronavirus disease 2019 (COVID-19) therapeutic agents, but also for airway regeneration studies.
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Automated amplification-free digital RNA detection platform for rapid and sensitive SARS-CoV-2 diagnosis. Commun Biol 2022; 5:473. [PMID: 35614128 PMCID: PMC9132978 DOI: 10.1038/s42003-022-03433-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 04/29/2022] [Indexed: 12/12/2022] Open
Abstract
In the ongoing COVID-19 pandemic, rapid and sensitive diagnosis of viral infection is a critical deterrent to the spread of SARS-CoV-2. To this end, we developed an automated amplification-free digital RNA detection platform using CRISPR-Cas13a and microchamber device (opn-SATORI), which automatically completes a detection process from sample mixing to RNA quantification in clinical specimens within ~9 min. Using the optimal Cas13a enzyme and magnetic beads technology, opn-SATORI detected SARS-CoV-2 genomic RNA with a LoD of < 6.5 aM (3.9 copies μL−1), comparable to RT-qPCR. Additionally, opn-SATORI discriminated between SARS-CoV-2 variants of concern, including alpha, delta, and omicron, with 98% accuracy. Thus, opn-SATORI can serve as a rapid and convenient diagnostic platform for identifying several types of viral infections. An automated amplification-free digital RNA detection platform using CRISPR-Cas13a and magnetic bead technology implemented in a microchamber device demonstrates sensitive SARS-CoV-2 genomic RNA detection and variant discrimination.
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Structural insight into Marburg virus nucleoprotein-RNA complex formation. Nat Commun 2022; 13:1191. [PMID: 35246537 PMCID: PMC8897395 DOI: 10.1038/s41467-022-28802-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 02/10/2022] [Indexed: 11/15/2022] Open
Abstract
The nucleoprotein (NP) of Marburg virus (MARV), a close relative of Ebola virus (EBOV), encapsidates the single-stranded, negative-sense viral genomic RNA (vRNA) to form the helical NP–RNA complex. The NP–RNA complex constitutes the core structure for the assembly of the nucleocapsid that is responsible for viral RNA synthesis. Although appropriate interactions among NPs and RNA are required for the formation of nucleocapsid, the structural basis of the helical assembly remains largely elusive. Here, we show the structure of the MARV NP–RNA complex determined using cryo-electron microscopy at a resolution of 3.1 Å. The structures of the asymmetric unit, a complex of an NP and six RNA nucleotides, was very similar to that of EBOV, suggesting that both viruses share common mechanisms for the nucleocapsid formation. Structure-based mutational analysis of both MARV and EBOV NPs identified key residues for helical assembly and subsequent viral RNA synthesis. Importantly, most of the residues identified were conserved in both viruses. These findings provide a structural basis for understanding the nucleocapsid formation and contribute to the development of novel antivirals against MARV and EBOV. Marburg virus causes severe hemorrhagic fever in humans. Here, the authors determine the structure of Marburg virus nucleoprotein–RNA complex by cryo-electron microscopy and provide mechanistic insight into the helical assembly of the nucleocapsid.
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Effect of Implicit Theory on Effort Allocation Strategies in Multiple Task-Choice Situations: An Investigation From a Socio-Ecological Perspective. Front Psychol 2021; 12:767101. [PMID: 34925169 PMCID: PMC8678568 DOI: 10.3389/fpsyg.2021.767101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 11/08/2021] [Indexed: 11/15/2022] Open
Abstract
Implicit theories refer to two assumptions that people make about the malleability of one’s ability. Previous studies have argued that incremental theorists (who believe that ability is malleable) are more adaptive than entity theorists (who believe that ability is fixed) when facing achievement setbacks. In the present research, we assumed that the adaptive implicit theory would be different when people could choose from a wider range of tasks. It was hypothesized that incremental theorists would sustain their efforts in the first task even when it was difficult, whereas entity theorists would try to find the most appropriate task. In a pair of laboratory experiments, participants had to maximize their outcomes when allowed to choose a task to engage in, from two options. When participants were allowed to practice the two tasks (Study 1), incremental theorists tended to allocate their effort solely to the first task, whereas entity theorists tended to put equal effort into both. When participants were informed that they could switch from the assigned task (Study 2), incremental theorists tended to persist in the first task regardless of its difficulty, whereas entity theorists tended to switch more quickly if the task was difficult. These results supported our hypothesis of two effort allocation strategies and implied that, in certain situations, entity theorists could be more adaptive than incremental theorists. Based on these findings, we conducted a social survey on the difficulty of switching tasks with a real-life setting as an environmental factor that determines the adaptive implicit theory (Study 3). It was revealed that the academic performance of incremental and entity theorists was moderated by the difficulty of switching tasks in their learning environment at school. Cultural differences in implicit theories may be explained by differences in the difficulty of switching tasks in education and career choices in each society.
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Non-Woven Infection Prevention Fabrics Coated with Biobased Cranberry Extracts Inactivate Enveloped Viruses Such as SARS-CoV-2 and Multidrug-Resistant Bacteria. Int J Mol Sci 2021; 22:12719. [PMID: 34884521 PMCID: PMC8657951 DOI: 10.3390/ijms222312719] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 11/17/2021] [Accepted: 11/22/2021] [Indexed: 01/08/2023] Open
Abstract
The Coronavirus Disease (COVID-19) pandemic is demanding the rapid action of the authorities and scientific community in order to find new antimicrobial solutions that could inactivate the pathogen SARS-CoV-2 that causes this disease. Gram-positive bacteria contribute to severe pneumonia associated with COVID-19, and their resistance to antibiotics is exponentially increasing. In this regard, non-woven fabrics are currently used for the fabrication of infection prevention clothing such as face masks, caps, scrubs, shirts, trousers, disposable gowns, overalls, hoods, aprons and shoe covers as protective tools against viral and bacterial infections. However, these non-woven fabrics are made of materials that do not exhibit intrinsic antimicrobial activity. Thus, we have here developed non-woven fabrics with antimicrobial coatings of cranberry extracts capable of inactivating enveloped viruses such as SARS-CoV-2 and the bacteriophage phi 6 (about 99% of viral inactivation in 1 min of viral contact), and two multidrug-resistant bacteria: the methicillin-resistant Staphylococcus aureus and the methicillin-resistant Staphylococcus epidermidis. The morphology, thermal and mechanical properties of the produced filters were characterized by optical and electron microscopy, differential scanning calorimetry, thermogravimetry and dynamic mechanical thermal analysis. The non-toxicity of these advanced technologies was ensured using a Caenorhabditis elegans in vivo model. These results open up a new prevention path using natural and biodegradable compounds for the fabrication of infection prevention clothing in the current COVID-19 pandemic and microbial resistant era.
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Antiviral Face Mask Functionalized with Solidified Hand Soap: Low-Cost Infection Prevention Clothing against Enveloped Viruses Such as SARS-CoV-2. ACS OMEGA 2021; 6:23495-23503. [PMID: 34514272 PMCID: PMC8424690 DOI: 10.1021/acsomega.1c03511] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 08/24/2021] [Indexed: 05/02/2023]
Abstract
Infection prevention clothing is becoming an essential protective tool in the current pandemic, especially because now we know that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can easily infect humans in poorly ventilated indoor spaces. However, commercial infection prevention clothing is made of fabrics that are not capable of inactivating the virus. Therefore, viral infections of symptomatic and asymptomatic individuals wearing protective clothing such as masks can occur through aerosol transmission or by contact with the contaminated surfaces of the masks, which are suspected as an increasing source of highly infectious biological waste. Herein, we report an easy fabrication method of a novel antiviral non-woven fabric containing polymer filaments that were coated with solidified hand soap. This extra protective fabric is capable of inactivating enveloped viruses such as SARS-CoV-2 and phage Φ6 within 1 min of contact. In this study, this antiviral fabric was used to fabricate an antiviral face mask and did not show any cytotoxic effect in human keratinocyte HaCaT cells. Furthermore, this antiviral non-woven fabric could be used for the fabrication of other infection prevention clothing such as caps, scrubs, shirts, trousers, disposable gowns, overalls, hoods, aprons, and shoe covers. Therefore, this low-cost technology could provide a wide range of infection-protective tools to combat COVID-19 and future pandemics in developed and underdeveloped countries.
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Antimicrobial Face Shield: Next Generation of Facial Protective Equipment against SARS-CoV-2 and Multidrug-Resistant Bacteria. Int J Mol Sci 2021; 22:9518. [PMID: 34502431 PMCID: PMC8431192 DOI: 10.3390/ijms22179518] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 08/23/2021] [Accepted: 08/24/2021] [Indexed: 12/19/2022] Open
Abstract
Transparent materials used for facial protection equipment provide protection against microbial infections caused by viruses and bacteria, including multidrug-resistant strains. However, transparent materials used for this type of application are made of materials that do not possess antimicrobial activity. They just avoid direct contact between the person and the biological agent. Therefore, healthy people can become infected through contact of the contaminated material surfaces and this equipment constitute an increasing source of infectious biological waste. Furthermore, infected people can transmit microbial infections easily because the protective equipment do not inactivate the microbial load generated while breathing, sneezing or coughing. In this regard, the goal of this work consisted of fabricating a transparent face shield with intrinsic antimicrobial activity that could provide extra-protection against infectious agents and reduce the generation of infectious waste. Thus, a single-use transparent antimicrobial face shield composed of polyethylene terephthalate and an antimicrobial coating of benzalkonium chloride has been developed for the next generation of facial protective equipment. The antimicrobial coating was analyzed by atomic force microscopy and field emission scanning electron microscopy with elemental analysis. This is the first facial transparent protective material capable of inactivating enveloped viruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in less than one minute of contact, and the methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis. Bacterial infections contribute to severe pneumonia associated with the SARS-CoV-2 infection, and their resistance to antibiotics is increasing. Our extra protective broad-spectrum antimicrobial composite material could also be applied for the fabrication of other facial protective tools such as such as goggles, helmets, plastic masks and space separation screens used for counters or vehicles. This low-cost technology would be very useful to combat the current pandemic and protect health care workers from multidrug-resistant infections in developed and underdeveloped countries.
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11
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Resistance of SARS-CoV-2 variants to neutralization by antibodies induced in convalescent patients with COVID-19. Cell Rep 2021; 36:109385. [PMID: 34237284 PMCID: PMC8226103 DOI: 10.1016/j.celrep.2021.109385] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Revised: 05/16/2021] [Accepted: 06/18/2021] [Indexed: 12/20/2022] Open
Abstract
Administration of convalescent plasma or neutralizing monoclonal antibodies (mAbs) is a potent therapeutic option for coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, SARS-CoV-2 variants with mutations in the spike protein have emerged in many countries. To evaluate the efficacy of neutralizing antibodies induced in convalescent patients against emerging variants, we isolate anti-spike mAbs from two convalescent COVID-19 patients infected with prototypic SARS-CoV-2 by single-cell sorting of immunoglobulin-G-positive (IgG+) memory B cells. Anti-spike antibody induction is robust in these patients, and five mAbs have potent neutralizing activities. The efficacy of most neutralizing mAbs and convalescent plasma samples is maintained against B.1.1.7 and mink cluster 5 variants but is significantly decreased against variants B.1.351 from South Africa and P.1 from Brazil. However, mAbs with a high affinity for the receptor-binding domain remain effective against these neutralization-resistant variants. Rapid spread of these variants significantly impacts antibody-based therapies and vaccine strategies against SARS-CoV-2.
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12
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Modeling SARS-CoV-2 infection and its individual differences with ACE2-expressing human iPS cells. iScience 2021; 24:102428. [PMID: 33880436 PMCID: PMC8051014 DOI: 10.1016/j.isci.2021.102428] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 03/19/2021] [Accepted: 04/09/2021] [Indexed: 02/05/2023] Open
Abstract
Genetic differences are a primary reason for differences in the susceptibility and severity of COVID-19. As induced pluripotent stem (iPS) cells maintain the genetic information of the donor, they can be used to model individual differences in SARS-CoV-2 infection in vitro. We found that human iPS cells expressing the SARS-CoV-2 receptor angiotensin-converting enzyme 2 (ACE2) (ACE2-iPS cells) can be infected w SARS-CoV-2. In infected ACE2-iPS cells, the expression of SARS-CoV-2 nucleocapsid protein, budding of viral particles, and production of progeny virus, double membrane spherules, and double-membrane vesicles were confirmed. We performed SARS-CoV-2 infection experiments on ACE2-iPS/ embryonic stem (ES) cells from eight individuals. Male iPS/ES cells were more capable of producing the virus compared with female iPS/ES cells. These findings suggest that ACE2-iPS cells can not only reproduce individual differences in SARS-CoV-2 infection in vitro but also are a useful resource to clarify the causes of individual differences in COVID-19 due to genetic differences.
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Protective Face Mask Filter Capable of Inactivating SARS-CoV-2, and Methicillin-Resistant Staphylococcus aureus and Staphylococcus epidermidis. Polymers (Basel) 2021; 13:E207. [PMID: 33435608 PMCID: PMC7827663 DOI: 10.3390/polym13020207] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 01/03/2021] [Accepted: 01/06/2021] [Indexed: 01/12/2023] Open
Abstract
Face masks have globally been accepted to be an effective protective tool to prevent bacterial and viral transmission, especially against indoor aerosol transmission. However, commercial face masks contain filters that are made of materials that are not capable of inactivating either SARS-CoV-2 or multidrug-resistant bacteria. Therefore, symptomatic and asymptomatic individuals can infect other people even if they wear them because some viable viral or bacterial loads can escape from the masks. Furthermore, viral or bacterial contact transmission can occur after touching the mask, which constitutes an increasing source of contaminated biological waste. Additionally, bacterial pathogens contribute to the SARS-CoV-2-mediated pneumonia disease complex, and their resistance to antibiotics in pneumonia treatment is increasing at an alarming rate. In this regard, herein, we report the development of a non-woven face mask filter fabricated with a biofunctional coating of benzalkonium chloride that is capable of inactivating more than 99% of SARS-CoV-2 particles in one minute of contact, and the life-threatening methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis (normalized antibacterial halos of 0.52 ± 0.04 and 0.72 ± 0.04, respectively). Nonetheless, despite the results obtained, further studies are needed to ensure the safety and correct use of this technology for the mass production and commercialization of this broad-spectrum antimicrobial face mask filter. Our novel protective non-woven face mask filter would be useful for many healthcare workers and researchers working in this urgent and challenging field.
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Effects of temperature increase during surgical drilling in acrylic resin. Technol Health Care 2019; 28:369-380. [PMID: 31796714 DOI: 10.3233/thc-191870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Acrylic resin is employed for drilling bone biomodels. Since drilling causes temperature rise, the mechanical properties of thermoplastic acrylic resin can be altered, consequently affecting drilling properties. However, it is currently unclear how this temperature increase impacts drilling. OBJECTIVE This study reports the effects of temperature rise on both mechanical and drilling properties through experiments in which acrylic resin is drilled under machining conditions employed in surgical operations. METHODS Drilling tests were performed using a surgical drill on medical acrylic resin under dry conditions to observe generated cutting chips and measure drilling properties such as torque, drilling time, and temperature rise. Dynamic mechanical analysis measurements were performed to consider temperature effects. RESULTS According to the morphological classification of the cutting chips, the drilling process is divided into three phases corresponding with the generation of cylindrical helix, waved, and rounded nubby chips respectively. During drilling, the temperature of the chips can exceed the glass transition temperature (100∘C) resulting in decreased viscoelasticity, which is associated with decreased torque. CONCLUSIONS While drilling acrylic resin under surgical machining conditions, increasing temperature can decrease torque and morphologically change cutting chips due to the decrease in mechanical properties above the glass transition temperature.
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Microtubule-dependent transport of arenavirus matrix protein demonstrated using live-cell imaging microscopy. Microscopy (Oxf) 2019; 68:450-456. [PMID: 31722015 DOI: 10.1093/jmicro/dfz034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Revised: 08/07/2019] [Accepted: 08/14/2019] [Indexed: 12/15/2022] Open
Abstract
Lassa virus (LASV), belonging to the family Arenaviridae, causes severe haemorrhagic manifestations and is associated with a high mortality rate in humans. Thus, it is classified as a biosafety level (BSL)-4 agent. Since countermeasures for LASV diseases are yet to be developed, it is important to elucidate the molecular mechanisms underlying the life cycle of the virus, including its viral and host cellular protein interactions. These underlying molecular mechanisms may serve as the key for developing novel therapeutic options. Lymphocytic choriomeningitis virus (LCMV), a close relative of LASV, is usually asymptomatic and is categorized as a BSL-2 agent. In the present study, we visualized the transport of viral matrix Z protein in LCMV-infected cells using live-cell imaging microscopy. We demonstrated that the transport of Z protein is mediated by polymerized microtubules. Interestingly, the transport of LASV Z protein showed characteristics similar to those of Z protein in LCMV-infected cells. The live-cell imaging system using LCMV provides an attractive surrogate measure for studying arenavirus matrix protein transport in BSL-2 laboratories. In addition, it could be also utilized to analyze the interactions between viral matrix proteins and the cellular cytoskeleton, as well as to evaluate the antiviral compounds that target the transport of viral matrix proteins.
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Generation of a purely clonal defective interfering influenza virus. Microbiol Immunol 2019; 63:164-171. [PMID: 30997933 DOI: 10.1111/1348-0421.12681] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 04/09/2019] [Accepted: 04/10/2019] [Indexed: 11/29/2022]
Abstract
Defective interfering (DI) influenza viruses carry a large deletion in a gene segment that interferes with the replication of infectious virus; thus, such viruses have potential for antiviral therapy. However, because DI viruses cannot replicate autonomously without the aid of an infectious helper virus, clonal DI virus stocks that are not contaminated with helper virus have not yet been generated. To overcome this problem, we used reverse genetics to generate a clonal DI virus with a PB2 DI gene, amplified the clonal DI virus using a cell line stably expressing the PB2 protein, and confirmed its ability to interfere with infectious virus replication in vitro. Thus, our approach is suitable for obtaining purely clonal DI viruses, will contribute to the understanding of DI virus interference mechanisms and can be used to develop DI virus-based antivirals.
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Hypocrisy and culture: Failing to practice what you preach receives harsher interpersonal reactions in independent (vs. interdependent) cultures. JOURNAL OF EXPERIMENTAL SOCIAL PSYCHOLOGY 2018. [DOI: 10.1016/j.jesp.2017.12.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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18
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Importance of the 1+7 configuration of ribonucleoprotein complexes for influenza A virus genome packaging. Nat Commun 2018; 9:54. [PMID: 29302061 PMCID: PMC5754346 DOI: 10.1038/s41467-017-02517-w] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 12/06/2017] [Indexed: 12/31/2022] Open
Abstract
The influenza A virus genome is composed of eight single-stranded negative-sense RNAs. Eight distinct viral RNA segments (vRNAs) are selectively packaged into progeny virions, with eight vRNAs in ribonucleoprotein complexes (RNPs) arranged in a specific “1+7” pattern, that is, one central RNP surrounded by seven RNPs. Here we report the genome packaging of an artificially generated seven-segment virus that lacks the hemagglutinin (HA) vRNA. Electron microscopy shows that, even in the presence of only seven vRNAs, the virions efficiently package eight RNPs arranged in the same “1+7” pattern as wild-type virions. Next-generation sequencing reveals that the virions specifically incorporate host-derived 18S and 28S ribosomal RNAs (rRNAs) seemingly as the eighth RNP in place of the HA vRNA. These findings highlight the importance of the assembly of eight RNPs into a specific “1+7” configuration for genome packaging in progeny virions and suggest a potential role for cellular RNAs in viral genome packaging. Influenza A virus (IAV) packages its eight genomic RNA segments in a specific “1+7” pattern. Here, the authors generate IAV that lack one RNA segment and show that ribosomal RNA is packaged in place of the eighth segment, suggesting that the 1+7 pattern is important for particle production.
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[Keep changing to remain unchanged: A way to maintain a cultural custom in the face of environmental change]. SHINRIGAKU KENKYU : THE JAPANESE JOURNAL OF PSYCHOLOGY 2016; 87:495-505. [PMID: 29630182 DOI: 10.4992/jjpsy.87.15051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
This is a micro-ethnographic study focusing on a traditional custom at Tōshi Island in Japan. When first-born sons in the island graduate from junior high school, they form a small group of neya-ko (quasi-brothers) and sleep over at neya-oyas’ (quasi-parents) house every night until they become 26 years old. They keep the quasi-family relationship alive and help each other all through life. We investigated the maintenance process of this cultural custom by participant observations and unstructured interviews. Because of the recent drastic environmental changes around the island, people face difficulties maintaining the custom. In spite of these circumstances, they have been able to maintain the custom not by challenging the environmental changes, but by constantly changing the custom itself to fit the environment. Their flexible decision making may derive from their ecological basis as fishermen. Based on the findings, we discuss the sustainability of cultural customs facing environmental changes.
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Abstract
Past research in cross-cultural psychology has emphasized a contrast between Western self-serving tendency and East Asian self-effacing tendency in attributions. The present author, however, poses a question to this simple dichotomy and presents some empirical evidence for indirect self-enhancement among Japanese. Participants were asked to recall their positive and negative life events and to make attributions. Results showed that Japanese tended to make self-effacing attributions for their success and failure. At the same time, however, they expected their parents, siblings, and close friends to make internal attributions for their success more than for their failure. In addition, they believed that these people understand them to a large extent. Japanese would not enhance or protect their self-esteem explicitly, but that they would do so indirectly through others' eyes.
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An Ultrasensitive Mechanism Regulates Influenza Virus-Induced Inflammation. PLoS Pathog 2015; 11:e1004856. [PMID: 26046528 PMCID: PMC4457877 DOI: 10.1371/journal.ppat.1004856] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 04/06/2015] [Indexed: 12/25/2022] Open
Abstract
Influenza viruses present major challenges to public health, evident by the 2009 influenza pandemic. Highly pathogenic influenza virus infections generally coincide with early, high levels of inflammatory cytokines that some studies have suggested may be regulated in a strain-dependent manner. However, a comprehensive characterization of the complex dynamics of the inflammatory response induced by virulent influenza strains is lacking. Here, we applied gene co-expression and nonlinear regression analysis to time-course, microarray data developed from influenza-infected mouse lung to create mathematical models of the host inflammatory response. We found that the dynamics of inflammation-associated gene expression are regulated by an ultrasensitive-like mechanism in which low levels of virus induce minimal gene expression but expression is strongly induced once a threshold virus titer is exceeded. Cytokine assays confirmed that the production of several key inflammatory cytokines, such as interleukin 6 and monocyte chemotactic protein 1, exhibit ultrasensitive behavior. A systematic exploration of the pathways regulating the inflammatory-associated gene response suggests that the molecular origins of this ultrasensitive response mechanism lie within the branch of the Toll-like receptor pathway that regulates STAT1 phosphorylation. This study provides the first evidence of an ultrasensitive mechanism regulating influenza virus-induced inflammation in whole lungs and provides insight into how different virus strains can induce distinct temporal inflammation response profiles. The approach developed here should facilitate the construction of gene regulatory models of other infectious diseases.
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Perceived Fairness of Pay: The Importance of Task versus Maintenance Inputs in Japan, South Korea, and Hong Kong. MANAGEMENT AND ORGANIZATION REVIEW 2015. [DOI: 10.1111/j.1740-8784.2009.00173.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AbstractThis study compares East Asians' evaluations of task and maintenance inputs in reward allocation decisions and examines the effects that inequity in various types of inputs and rewards have on fairness judgements. Based on a sample of 587 employees from various organizations in Hong Kong, Japan, and South Korea, we find that Hong Kong Chinese and South Korean employees are more likely to want their organizations and supervisors to emphasize maintenance inputs, while Japanese employees value task inputs in reward allocation. Results also show that there are significant country differences in fairness judgements associated with various types of inputs. For example, the positive relationship between pay level and perceived fairness of pay is significantly stronger when task contributions are high rather than low among Japanese employees but not among Hong Kong and South Korean employees. The concept of independent self-construal (similar to individualism at the societal level) seems to provide an adequate account of the country differences in choice of input preferences but not fairness judgements.
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Integrated network analysis reveals a novel role for the cell cycle in 2009 pandemic influenza virus-induced inflammation in macaque lungs. BMC SYSTEMS BIOLOGY 2012; 6:117. [PMID: 22937776 PMCID: PMC3481363 DOI: 10.1186/1752-0509-6-117] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Accepted: 08/18/2012] [Indexed: 12/17/2022]
Abstract
Background Annually, influenza A viruses circulate the world causing wide-spread sickness, economic loss, and death. One way to better defend against influenza virus-induced disease may be to develop novel host-based therapies, targeted at mitigating viral pathogenesis through the management of virus-dysregulated host functions. However, mechanisms that govern aberrant host responses to influenza virus infection remain incompletely understood. We previously showed that the pandemic H1N1 virus influenza A/California/04/2009 (H1N1; CA04) has enhanced pathogenicity in the lungs of cynomolgus macaques relative to a seasonal influenza virus isolate (A/Kawasaki/UTK-4/2009 (H1N1; KUTK4)). Results Here, we used microarrays to identify host gene sequences that were highly differentially expressed (DE) in CA04-infected macaque lungs, and we employed a novel strategy – combining functional and pathway enrichment analyses, transcription factor binding site enrichment analysis and protein-protein interaction data – to create a CA04 differentially regulated host response network. This network describes enhanced viral RNA sensing, immune cell signaling and cell cycle arrest in CA04-infected lungs, and highlights a novel, putative role for the MYC-associated zinc finger (MAZ) transcription factor in regulating these processes. Conclusions Our findings suggest that the enhanced pathology is the result of a prolonged immune response, despite successful virus clearance. Most interesting, we identify a mechanism which normally suppresses immune cell signaling and inflammation is ineffective in the pH1N1 virus infection; a dyregulatory event also associated with arthritis. This dysregulation offers several opportunities for developing strain-independent, immunomodulatory therapies to protect against future pandemics.
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The nucleoprotein and matrix protein segments of H5N1 influenza viruses are responsible for dominance in embryonated eggs. J Gen Virol 2011; 92:1645-1649. [PMID: 21471324 DOI: 10.1099/vir.0.030247-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Since their emergence in 1996 in southern China, highly pathogenic H5N1 avian influenza viruses have spread widely and continue to circulate in some countries. Genetic reassortment has created multiple H5N1 virus lineages, some of which are dominant in nature. However, the mechanism by which certain H5N1 influenza virus lineages (or genotypes) become dominant in avian species remains unknown. Here, we used competitive inoculation and genetic analysis of the resultant viruses to show that the nucleoprotein (NP) and matrix protein (M) segments of Fujian-like viruses (clade 2.3.4), which became predominant in southern China in mid-2006, are responsible for viral dominance in embryonated eggs. We further found that specific residues in the NP and M proteins play key roles in conferring this viral dominance; specifically, a glutamic acid at position 66 in M2 was conserved among the Fujian-like viruses. These results suggest roles for these viral proteins in influenza virus dominance.
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Abstract
TOC summary: Pigs may serve as intermediate hosts in which this avian virus can adapt to mammals. Pigs have long been considered potential intermediate hosts in which avian influenza viruses can adapt to humans. To determine whether this potential exists for pigs in Indonesia, we conducted surveillance during 2005–2009. We found that 52 pigs in 4 provinces were infected during 2005–2007 but not 2008–2009. Phylogenetic analysis showed that the viruses had been introduced into the pig population in Indonesia on at least 3 occasions. One isolate had acquired the ability to recognize a human-type receptor. No infected pig had influenza-like symptoms, indicating that influenza A (H5N1) viruses can replicate undetected for prolonged periods, facilitating avian virus adaptation to mammalian hosts. Our data suggest that pigs are at risk for infection during outbreaks of influenza virus A (H5N1) and can serve as intermediate hosts in which this avian virus can adapt to mammals.
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Pathogenicity of highly pathogenic avian H5N1 influenza A viruses isolated from humans between 2003 and 2008 in northern Vietnam. J Gen Virol 2010; 91:2485-90. [PMID: 20592108 PMCID: PMC3052597 DOI: 10.1099/vir.0.021659-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2010] [Accepted: 06/28/2010] [Indexed: 11/29/2022] Open
Abstract
Vietnam is one of the countries most affected by highly pathogenic H5N1 influenza A viruses. To evaluate the potential pathogenicity in mammals of H5N1 viruses isolated from humans in Vietnam, we determined the sequences of all eight genes of 22 human isolates collected between 2003 and 2008 and compared their virulence in mice. The isolates were classified into clade 1 and clade 2.3.4 and differed in pathogenicity for mice. Whilst lysine at position 627 of PB2 (PB2-627K) is a critical virulence determinant for clade 2.3.4 viruses, asparagine at position 701 of PB2 and other unknown virulence determinants appear to be involved in the high pathogenicity of clade 1 viruses, warranting further studies to determine the factors responsible for the high virulence of H5N1 viruses in mammals.
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The HA and NS genes of human H5N1 influenza A virus contribute to high virulence in ferrets. PLoS Pathog 2010; 6:e1001106. [PMID: 20862325 PMCID: PMC2940759 DOI: 10.1371/journal.ppat.1001106] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2010] [Accepted: 08/16/2010] [Indexed: 11/23/2022] Open
Abstract
Highly pathogenic H5N1 influenza A viruses have spread across Asia, Europe, and Africa. More than 500 cases of H5N1 virus infection in humans, with a high lethality rate, have been reported. To understand the molecular basis for the high virulence of H5N1 viruses in mammals, we tested the virulence in ferrets of several H5N1 viruses isolated from humans and found A/Vietnam/UT3062/04 (UT3062) to be the most virulent and A/Vietnam/UT3028/03 (UT3028) to be avirulent in this animal model. We then generated a series of reassortant viruses between the two viruses and assessed their virulence in ferrets. All of the viruses that possessed both the UT3062 hemagglutinin (HA) and nonstructural protein (NS) genes were highly virulent. By contrast, all those possessing the UT3028 HA or NS genes were attenuated in ferrets. These results demonstrate that the HA and NS genes are responsible for the difference in virulence in ferrets between the two viruses. Amino acid differences were identified at position 134 of HA, at positions 200 and 205 of NS1, and at positions 47 and 51 of NS2. We found that the residue at position 134 of HA alters the receptor-binding property of the virus, as measured by viral elution from erythrocytes. Further, both of the residues at positions 200 and 205 of NS1 contributed to enhanced type I interferon (IFN) antagonistic activity. These findings further our understanding of the determinants of pathogenicity of H5N1 viruses in mammals. Highly pathogenic H5N1 influenza A viruses have caused more than 500 human infections with approximately 60% lethality in 15 countries and continue to pose a pandemic threat. The recent worldwide spread of pandemic H1N1 influenza A viruses raises the concern of reassortment between the H5N1 viruses and other influenza viruses. However, the molecular determinants for high virulence of the H5N1 viruses in mammals are not fully understood. We, therefore, investigated their virulence in a ferret model, which is a widely accepted animal model for assessing human influenza virus replication. We identified an amino acid in hemagglutinin and four amino acids in nonstructural proteins that are associated with high virulence of a human H5N1 virus, A/Vietnam/UT3062/04. We also found that the amino acid in hemagglutinin changes its receptor-binding property and the amino acids in nonstructural protein 1 affect its interferon antagonistic ability. These findings provide insight into the pathogenesis of H5N1 viruses in mammals.
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In vitro and in vivo characterization of new swine-origin H1N1 influenza viruses. Nature 2009; 460:1021-5. [PMID: 19672242 PMCID: PMC2748827 DOI: 10.1038/nature08260] [Citation(s) in RCA: 849] [Impact Index Per Article: 56.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2009] [Accepted: 07/03/2009] [Indexed: 12/11/2022]
Abstract
Influenza A viruses cause recurrent outbreaks of local or global scale with potentially severe consequences for human health and the global economy. Recently, a new strain of influenza A virus was detected that causes disease in and transmits among humans, probably owing to little or no pre-existing immunity to the new strain. On June 11, 2009, the WHO declared that the infections caused by the new strain had reached pandemic proportion. Characterized as an influenza A virus of the H1N1 subtype, the genomic segments of the new strain were most closely related to swine viruses1. Most human infections with swine-origin H1N1 influenza viruses (S-OIVs) appear to be mild; however, more than 50% of hospitalized individuals do not have underlying health issues, attesting to the pathogenic potential of S-OIVs. To better assess the risk posed by the new virus, we characterized one of the first US S-OIV isolates, A/California/04/09 (H1N1; CA04), as well as several other S-OIV isolates, in vitro and in vivo. In mice and ferrets, CA04 and other S-OIV isolates tested replicate more efficiently than a currently circulating human H1N1 virus. In addition, CA04 replicates efficiently in nonhuman primates, causes more severe pathologic lesions in the lungs of infected mice, ferrets, and nonhuman primates than a currently circulating human H1N1 virus, and transmits among ferrets. In specific-pathogen free miniature pigs, CA04 replicates without clinical symptoms. The assessment of human sera from different age groups suggests that infection with human H1N1 viruses antigenically closely related to viruses circulating in 1918 confers neutralizing antibody activity to CA04. Finally, we show that CA04 is sensitive to approved and experimental antiviral drugs, suggesting these compounds as a first line of defence against the recently declared S-OIV pandemic.
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Perception of achievement attribution in individual and group contexts: Comparative analysis of Japanese, Korean, and Asian-American results. ASIAN JOURNAL OF SOCIAL PSYCHOLOGY 2009. [DOI: 10.1111/j.1467-839x.2009.01285.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Phylogenetic characterization of H5N1 avian influenza viruses isolated in Indonesia from 2003-2007. Virology 2009; 390:13-21. [PMID: 19464724 DOI: 10.1016/j.virol.2009.04.024] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2009] [Revised: 02/12/2009] [Accepted: 04/29/2009] [Indexed: 11/17/2022]
Abstract
The wide distribution of H5N1 highly pathogenic avian influenza viruses is a global threat to human health. Indonesia has had the largest number of human infections and fatalities caused by these viruses. To understand the enzootic conditions of the viruses in Indonesia, twenty-four H5N1 viruses isolated from poultry from 2003 to 2007 were phylogenetically characterized. Although previous studies exclusively classified the Indonesian viruses into clades 2.1.1-2.1.3, our phylogenetic analyses showed a new sublineage that did not belong to any of the present clades. In addition, novel reassortant viruses were identified that emerged between this new sublineage and other clades in 2005-2006 on Java Island. H5N1 viruses were introduced from Java Island to Sulawesi, Kalimantan, and Sumatra Island on multiple occasions from 2003-2007, causing the geographical expansion of these viruses in Indonesia. These findings identify Java Island as the epicenter of the Indonesian H5N1 virus expansion.
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A comparison of the pathogenicity of avian and swine H5N1 influenza viruses in Indonesia. Arch Virol 2009; 154:677-81. [PMID: 19288052 DOI: 10.1007/s00705-009-0353-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2008] [Accepted: 02/27/2009] [Indexed: 10/21/2022]
Abstract
Highly pathogenic avian influenza H5N1 viruses are circulating in many countries. We recently discovered that these viruses have been transmitted to pigs on multiple occasions in Indonesia. To investigate whether avian H5N1 influenza viruses adapted to mammals through their introduction into pigs, we examined the growth of avian and swine isolates in cell culture and compared their pathogenicity in mice. We found that swine isolates were less virulent to mice than avian isolates, suggesting that the viruses became attenuated during their replication in pigs. Continuous surveillance of H5N1 viruses among pigs is clearly warranted.
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Pathogenicity of Chinese H5N1 highly pathogenic avian influenza viruses in pigeons. Arch Virol 2008; 153:1821-6. [PMID: 18779923 DOI: 10.1007/s00705-008-0193-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2008] [Accepted: 07/30/2008] [Indexed: 11/30/2022]
Abstract
It has long been thought that pigeons are resistant against H5 highly pathogenic avian influenza (HPAI) viruses. Recently, however, highly pathogenic H5N1 avian influenza viruses have demonstrated distinct biological properties that may be capable of causing disease in pigeons. To examine the susceptibility of domestic pigeons to recent H5N1 viruses, we inoculated pigeons using H5N1 viruses isolated in China from 2002 to 2004. Within 21 days following inoculation, all pigeons had survived and fully recovered from temporary clinical signs. However, seroconversion assays demonstrated that several viruses did in fact establish infection in pigeons and caused a certain amount of viral shedding in the oropharynx and cloaca. There was not, however, a definitive relationship between viral shedding and viral origin. Viruses were also inconsistently isolated from various organs of pigeons in infected groups. Pathological examination revealed that the infection had started as respiratory inflammation and caused the most severe lesions in the brain in later stages. These results indicate that pigeons are susceptible to the more recent Asian H5N1 HPAI and could be a source of infection to other animals, including humans.
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Limited compatibility between the RNA polymerase components of influenza virus type A and B. Virus Res 2008; 135:161-5. [PMID: 18455827 DOI: 10.1016/j.virusres.2008.03.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2008] [Revised: 03/11/2008] [Accepted: 03/12/2008] [Indexed: 11/19/2022]
Abstract
Reassortants between type A and B influenza viruses have not been detected in nature, although both viruses co-circulate in human populations. One explanation for this may be functional incompatibility of RNA transcription and replication between type A and B viruses. To test this possibility, we constructed type A/B mosaic polymerase machinery, containing PB2, PB1, PA and nucleoprotein from each of the two virus types, and assessed their polymerase activities with a type A promoter in a reporter assay. Type B polymerase machinery containing homologous components was functional with the type A promoter albeit to various extents depending on the segments from which the regions downstream of the promoter sequence were derived, indicating functional compatibility between the type A promoter and B polymerase machinery. However, all of the A/B mosaic polymerase machinery, except that containing PA from a type A and the others from a type B virus strain, did not function with the type A promoter, indicating limited compatibility among polymerase components of both types. Taken together, these data suggest that incompatibility among components of the polymerase machinery for RNA transcription and replication alone is not responsible for the lack of heterotypic reassortants.
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Enhanced growth of seed viruses for H5N1 influenza vaccines. Virology 2007; 366:23-7. [PMID: 17651774 PMCID: PMC2827194 DOI: 10.1016/j.virol.2007.07.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2007] [Revised: 06/15/2007] [Accepted: 07/02/2007] [Indexed: 11/28/2022]
Abstract
Seed viruses used to produce inactivated H5N1 influenza vaccines are recombinant viruses with modified avirulent-type hemagglutinin (HA) and intact neuraminidase (NA) genes, both derived from an H5N1 isolate, and all remaining genes from the PR8 strain, which grows well in eggs. However, some reassortants grow suboptimally in eggs, imposing obstacles to timely, cost-efficient vaccine production. Here, we demonstrate that our PR8 strain supports better in ovo growth than the PR8 strain used for the WHO-recommended seed virus, NIBRG-14. Moreover, inclusion of an alternative NA protein further enhanced viral growth in eggs. These findings suggest that our H5N1 vaccine candidates would increase the availability of H5N1 vaccine doses at the onset of a new pandemic.
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Abstract
The viral replication cycle concludes with the assembly of viral components to form progeny virions. For influenza A viruses, the matrix M1 protein and two membrane integral glycoproteins, hemagglutinin and neuraminidase, function cooperatively in this process. Here, we asked whether another membrane protein, the M2 protein, plays a role in virus assembly. The M2 protein, comprising 97 amino acids, possesses the longest cytoplasmic tail (54 residues) of the three transmembrane proteins of influenza A viruses. We therefore generated a series of deletion mutants of the M2 cytoplasmic tail by reverse genetics. We found that mutants in which more than 22 amino acids were deleted from the carboxyl terminus of the M2 tail were viable but grew less efficiently than did the wild-type virus. An analysis of the virions suggested that viruses with M2 tail deletions of more than 22 carboxy-terminal residues apparently contained less viral ribonucleoprotein complex than did the wild-type virus. These M2 tail mutants also differ from the wild-type virus in their morphology: while the wild-type virus is spherical, some of the mutants were filamentous. Alanine-scanning experiments further indicated that amino acids at positions 74 to 79 of the M2 tail play a role in virion morphogenesis and affect viral infectivity. We conclude that the M2 cytoplasmic domain of influenza A viruses plays an important role in viral assembly and morphogenesis.
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Molecular characterization of the hemagglutinin and neuraminidase genes of H5N1 influenza A viruses isolated from poultry in Vietnam from 2004 to 2005. J Vet Med Sci 2007; 68:527-31. [PMID: 16757902 DOI: 10.1292/jvms.68.527] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Highly pathogenic H5N1 avian influenza A viruses have been spreading among domestic poultry, wild aquatic birds, and humans in many Asian countries since 2003. The largest number of patients, to date, infected with the H5N1 viruses are in Vietnam, where these viruses continue to cause outbreaks in domestic poultry. Here, we molecularly characterized the hemagglutinin and neuraminidase genes of nine H5N1 viruses isolated between January 2004 and August 2005 from domestic poultry in Vietnam. We found that several groups of highly pathogenic H5N1 avian influenza viruses are circulating among these birds, which suggests that H5N1 viruses of different lineages have been introduced into Vietnam multiple times.
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A serological switching from anti-dsDNA to anti-Sm antibodies coincided with severe clinical manifestations of systemic lupus erythematosus (hemophagocytosis, profundus and psychosis). Lupus 2007; 16:67-9. [PMID: 17283590 DOI: 10.1177/0961203306071432] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
MESH Headings
- Administration, Oral
- Antibodies, Antinuclear/blood
- Antibodies, Antinuclear/immunology
- Antibody Specificity
- Autoantibodies/blood
- Autoantibodies/immunology
- Autoantigens/immunology
- Cyclosporine/administration & dosage
- Cyclosporine/therapeutic use
- DNA/immunology
- Disease Progression
- Drug Therapy, Combination
- Fever/etiology
- Humans
- Immunosuppressive Agents/administration & dosage
- Immunosuppressive Agents/therapeutic use
- Infusions, Intravenous
- Interleukin-6/cerebrospinal fluid
- Lupus Erythematosus, Systemic/complications
- Lupus Erythematosus, Systemic/immunology
- Lupus Erythematosus, Systemic/psychology
- Lymphohistiocytosis, Hemophagocytic/etiology
- Memory Disorders/etiology
- Methylprednisolone/administration & dosage
- Methylprednisolone/therapeutic use
- Prednisolone/administration & dosage
- Prednisolone/therapeutic use
- Psychotic Disorders/etiology
- Ribonucleoproteins, Small Nuclear/immunology
- Skin/pathology
- snRNP Core Proteins
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Haemagglutinin mutations responsible for the binding of H5N1 influenza A viruses to human-type receptors. Nature 2007; 444:378-82. [PMID: 17108965 DOI: 10.1038/nature05264] [Citation(s) in RCA: 461] [Impact Index Per Article: 27.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2006] [Accepted: 09/21/2006] [Indexed: 02/07/2023]
Abstract
H5N1 influenza A viruses have spread to numerous countries in Asia, Europe and Africa, infecting not only large numbers of poultry, but also an increasing number of humans, often with lethal effects. Human and avian influenza A viruses differ in their recognition of host cell receptors: the former preferentially recognize receptors with saccharides terminating in sialic acid-alpha2,6-galactose (SAalpha2,6Gal), whereas the latter prefer those ending in SAalpha2,3Gal (refs 3-6). A conversion from SAalpha2,3Gal to SAalpha2,6Gal recognition is thought to be one of the changes that must occur before avian influenza viruses can replicate efficiently in humans and acquire the potential to cause a pandemic. By identifying mutations in the receptor-binding haemagglutinin (HA) molecule that would enable avian H5N1 viruses to recognize human-type host cell receptors, it may be possible to predict (and thus to increase preparedness for) the emergence of pandemic viruses. Here we show that some H5N1 viruses isolated from humans can bind to both human and avian receptors, in contrast to those isolated from chickens and ducks, which recognize the avian receptors exclusively. Mutations at positions 182 and 192 independently convert the HAs of H5N1 viruses known to recognize the avian receptor to ones that recognize the human receptor. Analysis of the crystal structure of the HA from an H5N1 virus used in our genetic experiments shows that the locations of these amino acids in the HA molecule are compatible with an effect on receptor binding. The amino acid changes that we identify might serve as molecular markers for assessing the pandemic potential of H5N1 field isolates.
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Abstract
Ebolavirus is responsible for highly lethal hemorrhagic fever. Like all viruses, it must reproduce its various components and assemble them in cells in order to reproduce infectious virions and perpetuate itself. To generate infectious Ebolavirus, a viral genome-protein complex called the nucleocapsid (NC) must be produced and transported to the cell surface, incorporated into virions, and then released from cells. To further our understanding of the Ebolavirus life cycle, we expressed the various viral proteins in mammalian cells and examined them ultrastructurally and biochemically. Expression of nucleoprotein alone led to the formation of helical tubes, which likely serve as a core for the NC. The matrix protein VP40 was found to be critical for transport of NCs to the cell surface and for the incorporation of NCs into virions, where interaction between nucleoprotein and the matrix protein VP40 is likely essential for these processes. Examination of virus-infected cells revealed that virions containing NCs mainly emerge horizontally from the cell surface, whereas empty virions mainly bud vertically, suggesting that horizontal budding is the major mode of Ebolavirus budding. These data form a foundation for the identification and development of potential antiviral agents to combat the devastating disease caused by this virus. Ebolavirus is a causative agent of a severe, mostly fatal hemorrhagic fever in humans. Like all viruses, it must reproduce its various components and assemble them to reproduce progeny virus particles. However, because Ebolavirus needs special containment for biosafety, progress in understanding its morphogenesis has been slow, resulting in no effective therapies currently available for humans. To further our understanding of the Ebolavirus life cycle, the authors examined the specific interactions among viral proteins and the processes of Ebolavirus morphogenesis. It is demonstrated that nucleoprotein likely serves as a core for the nucleocapsid (NC) complex, which is critical for replication and transcription of viral genome. The interaction of nucleoprotein with matrix protein VP40 is found to be essential for transport of NCs to the cell surface and for the incorporation of NCs into virions, resulting in the formation of mature virus particles. Unique among all viruses to our knowledge, Ebolavirus particles containing NCs mainly emerge horizontally from the cell surface, whereas the other viruses bud vertically. These findings form a foundation for the identification and development of potential antiviral agents to combat the devastating disease caused by this virus.
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Contributions of two nuclear localization signals of influenza A virus nucleoprotein to viral replication. J Virol 2006; 81:30-41. [PMID: 17050598 PMCID: PMC1797272 DOI: 10.1128/jvi.01434-06] [Citation(s) in RCA: 178] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The RNA genome of influenza A virus, which forms viral ribonucleoprotein complexes (vRNPs) with viral polymerase subunit proteins (PA, PB1, and PB2) and nucleoprotein (NP), is transcribed and replicated in the nucleus. NP, the major component of vRNPs, has at least two amino acid sequences that serve as nuclear localization signals (NLSs): an unconventional NLS (residues 3 to 13; NLS1) and a bipartite NLS (residues 198 to 216; NLS2). Although both NLSs are known to play a role in nuclear transport, their relative contributions to viral replication are poorly understood. We therefore investigated their contributions to NP subcellular/subnuclear localization, viral RNA (vRNA) transcription, and viral replication. Abolishing the unconventional NLS caused NP to localize predominantly to the cytoplasm and affected its activity in vRNA transcription. However, we were able to create a virus whose NP contained amino acid substitutions in NLS1 known to abolish its nuclear localization function, although this virus was highly attenuated. These results indicate that while the unconventional NLS is not essential for viral replication, it is necessary for efficient viral mRNA synthesis. On the other hand, the bipartite NLS, whose contribution to the nuclear transport of NP is limited, was essential for vRNA transcription and NP's nucleolar accumulation. A virus with nonfunctional NLS2 could not be generated. Thus, the bipartite NLS, but not the unconventional NLS, of NP is essential for influenza A virus replication.
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Pathogenicity of H5N1 influenza A viruses isolated in Vietnam between late 2003 and 2005. J Vet Med Sci 2006; 68:735-7. [PMID: 16891788 DOI: 10.1292/jvms.68.735] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Since late 2003, highly pathogenic H5N1 influenza A viruses have spread among poultry and wild aquatic birds in Asian countries. Transmission of these viruses to humans can be lethal. Most human cases of infection with H5N1 viruses have occurred in Vietnam. Therefore, to understand the pathogenicity in mammals of these H5N1 viruses, we took viruses isolated from poultry (5 strains) and humans (2 strains) in Vietnam and tested their virulence in mice. The results showed that the H5N1 viruses from humans were pathogenic in mice and that one avian isolate was also pathogenic. These findings suggested that the H5N1 viruses circulating in poultry adapted during replication in humans or that strains pathogenic in mice were transmitted directly to humans.
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[Selective packaging mechanism for influenza A virus]. TANPAKUSHITSU KAKUSAN KOSO. PROTEIN, NUCLEIC ACID, ENZYME 2006; 51:1596-601. [PMID: 16944844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
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Abstract
Severe hemorrhage at multiple organs is frequently observed in chickens infected with highly pathogenic avian influenza (HPAI) A viruses. In this study we examined whether HPAI virus infection leads to coagulation disorder in chickens. Pathological examinations showed that the fibrin thrombi were formed in arterioles at the lung, associated with the viral antigens in endothelial cells of chickens infected intravenously with HPAI virus. Hematological analyses of peripheral blood collected from the chickens revealed that coagulopathy was initiated at early stage of infection when viral antigens were detected only in the endothelial cells and monocytes/macrophages. Furthermore, gene expression of the tissue factor, the main initiator of blood coagulation, was upregulated in the spleen, lung, and brain of HPAI virus-infected chickens. These results suggest that dysfunction of endothelial cells and monocytes/macrophages upon HPAI virus infection may induce hemostasis abnormalities represented by the excessive blood coagulation and consumptive coagulopathy in chickens.
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Abstract
The genome of influenza A viruses comprises eight negative-strand RNA segments. Although all eight segments must be present in cells for efficient viral replication, the mechanism(s) by which these viral RNA (vRNA) segments are incorporated into virions is not fully understood. We recently found that sequences at both ends of the coding regions of the HA, NA, and NS vRNA segments of A/WSN/33 play important roles in the incorporation of these vRNAs into virions. In order to similarly identify the regions of the PB2, PB1, and PA vRNAs of this strain that are critical for their incorporation, we generated a series of mutant vRNAs that possessed the green fluorescent protein gene flanked by portions of the coding and noncoding regions of the respective segments. For all three polymerase segments, deletions at the ends of their coding regions decreased their virion incorporation efficiencies. More importantly, these regions not only affected the incorporation of the segment in which they reside, but were also important for the incorporation of other segments. This effect was most prominent with the PB2 vRNA. These findings suggest a hierarchy among vRNA segments for virion incorporation and may imply intersegment association of vRNAs during virus assembly.
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Abstract
The persistence of H5N1 avian influenza viruses in many Asian countries and their ability to cause fatal infections in humans have raised serious concerns about a global flu pandemic. Here we report the isolation of an H5N1 virus from a Vietnamese girl that is resistant to the drug oseltamivir, which is an inhibitor of the viral enzyme neuraminidase and is currently used for protection against and treatment of influenza. Further investigation is necessary to determine the prevalence of oseltamivir-resistant H5N1 viruses among patients treated with this drug.
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Importance of both the coding and the segment-specific noncoding regions of the influenza A virus NS segment for its efficient incorporation into virions. J Virol 2005; 79:3766-74. [PMID: 15731270 PMCID: PMC1075679 DOI: 10.1128/jvi.79.6.3766-3774.2005] [Citation(s) in RCA: 150] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The genome of influenza A virus consists of eight single-strand negative-sense RNA segments, each comprised of a coding region and a noncoding region. The noncoding region of the NS segment is thought to provide the signal for packaging; however, we recently showed that the coding regions located at both ends of the hemagglutinin and neuraminidase segments were important for their incorporation into virions. In an effort to improve our understanding of the mechanism of influenza virus genome packaging, we sought to identify the regions of NS viral RNA (vRNA) that are required for its efficient incorporation into virions. Deletion analysis showed that the first 30 nucleotides of the 3' coding region are critical for efficient NS vRNA incorporation and that deletion of the 3' segment-specific noncoding region drastically reduces NS vRNA incorporation into virions. Furthermore, silent mutations in the first 30 nucleotides of the 3' NS coding region reduced the incorporation efficiency of the NS segment and affected virus replication. These results suggested that segment-specific noncoding regions together with adjacent coding regions (especially at the 3' end) form a structure that is required for efficient influenza A virus vRNA packaging.
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Interferon-beta induction/interferon-alpha2b plus ribavirin therapy in patients with chronic hepatitis C. INTERNATIONAL JOURNAL OF CLINICAL PHARMACOLOGY RESEARCH 2005; 25:71-6. [PMID: 16060397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Treatment of chronic hepatitis C virus (HCV) infection with interferon (IFN) and ribavirin improves the rate of eradication of the virus by less than 20% in patients with genotype 1b and a high viral load. In this study we assessed whether IFN-beta induction/IFN-alpha2b plus ribavirin enhances the efficacy of the therapy in patients with chronic hepatitis C. The efficacy of IFN-beta induction/IFN-alpha2b plus ribavirin therapy (group A, n=7) was compared with that of IFN-alpha2b plus ribavirin (group B, n=7) in 14 patients with high levels of HCV-RNA (> 100 K/U/ml). No significant differences were observed in the clearance of HCV-RNA between the two groups (A and B, respectively) 2 weeks after the start of the treatment (0% and 14.3%), at the end of the treatment (71.4% and 100%) and 6 months after the end of the treatment (28.6% and 14.3%). Recovery was complete in 28.6% and 14.3%, transient in 42.9% and 85.7% and absent in 28.6% and 0% in groups A and B, respectively. Early log changes in the viral load from the baseline after 2 weeks of treatment were 2.41 +/- 0.91 and 2.77 +/- 0.20 in groups A and B, respectively, with no significant difference between the two groups. In the present study, we were not able to demonstrate that IFN-beta induction/IFN-alpha2b plus ribavirin therapy was superior to IFN-alpha2b plus ribavirin therapy in patients with genotype 1b and high viral loads.
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[When "self-effacement" disappears: narratives of personal and group successes depending on an in group relationship]. SHINRIGAKU KENKYU : THE JAPANESE JOURNAL OF PSYCHOLOGY 2003; 74:253-62. [PMID: 14584256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
The distinction between ingroup and outgroup has played an important role in group process research. However, much less attention has been paid to variations among ingroups. In this study, we attempted to demonstrate that different ingroups could have different psychological impacts on self and group serving or effacing behavior. In our social survey. Japanese respondents evaluated the importance and psychological meaning of two typical ingroups: their family and another social group in which they spent most of their time. They were also asked about their behavior in the presence of ingroup members from each group. Results indicated that people showed a self-effacing tendency in the social group, whereas they showed a self-serving tendency in their family. At the same time, they showed a group-serving tendency when they talked about the social group, but they showed the opposite, i.e., a group-effacing tendency, when they talked about their family. These differences are explained in terms of relationships with ingroup members.
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Cloning of peroxisomal ascorbate peroxidase gene from barley and enhanced thermotolerance by overexpressing in Arabidopsis thaliana. Gene 2001; 273:23-7. [PMID: 11483357 DOI: 10.1016/s0378-1119(01)00566-2] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A full-length cDNA clone (HvAPX1) encoding a peroxisomal type ascorbate peroxidase was isolated from barley (Hordeum vulgare cv. Haruna-nijyo) leaves by differential display. The deduced amino acid sequence of the HvAPX1 gene had 75.3% homology to that from the Gossypium hirsutum glyoxysomal APX gene and 72.1% homology to that from the Arabidopsis thaliana peroxisomal APX gene, APX3. Southern blot analysis indicated that a single-copy gene in the barley genome encoded HvAPX1. Northern blot analysis showed that the HvAPX1 transcript increased remarkably in response to heat, salt and abscisic acid treatment. Induction was not caused by treatment with hydrogen peroxide. The HvAPX1 gene was introduced into A. thaliana under control of the 35S RNA promoter of the cauliflower mosaic virus. The transgenic plants were significantly more tolerant to heat stress as compared with the wild-type.
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Reduction of reaction differences between human mercaptalbumin and human nonmercaptalbumin measured by the bromcresol purple method. Clin Chim Acta 1999; 289:69-78. [PMID: 10556654 DOI: 10.1016/s0009-8981(99)00158-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Although the bromcresol purple (BCP) method provides high specificity in measurements of serum albumin concentrations, we discovered a reaction difference between the values for human mercaptalbumin (HMA) and human nonmercaptalbumin (HNA) measured by the BCP. We found that the color intensity of HMA with BCP present in the reduced form in the albumin of fresh serum, was lower than for HNA. While maintaining specificity for albumin, we reduced the reaction difference between HMA and HNA, with the addition of sodium dodecylsulfate and 5,5'-dithiobis(2-nitrobenzoic acid) to the BCP reagent. The mean albumin concentration by the BCP procedure for 63 fresh sera and the 63 sera stored for 2 days at room temperature were 35.6 g/L and 38.1 g/L, respectively. Those by the modified BCP procedure were 39.8 g/L and 39.9 g/L, respectively. The difference in measured values between the fresh and stored sera which is believed to be caused by the conversion of HMA to HNA during the storage of sera was not observed in the case of the modified BCP procedure. Our modified BCP method is effective in eliminating uncertainty of the albumin concentration assigned to assay calibrators for the conventional BCP method.
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