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This study aimed to compare the SARS-CoV-2-inactivation activity and virucidal mechanisms of ozonated water （OW） with those of slightly acidic electrolyzed water （SAEW） and 70% ethanol （EtOH）. SARS-CoV-2-inactivation activity was evaluated in a virus solution containing 1%, 20% or 40% fetal bovine serum （FBS） with OW, SAEW or EtOH at a virus-to-test solution ratio of 1：9, 1：19 or 1：99 for a reaction time of 20 s. EtOH showed the strongest virucidal activity, followed by SAEW and OW. Even though EtOH potently inactivated the virus despite the 40% FBS concentration, virus inactivation by OW and SAEW decreased in proportion to the increase in FBS concentration. Nevertheless, OW and SAEW showed potent virucidal activity with 40% FBS at a virus-to-test solution ratio of 1：99. Real-time PCR targeting the viral genome revealed that cycle threshold values in the OW and SAEW groups were significantly higher than those in the control group, suggesting that OW and SAEW disrupted the viral genome. Western blotting analysis targeting the recombinant viral spike protein S1 subunit showed a change in the specific band into a ladder upon treatment with OW and SAEW. OW and SAEW may cause conformational changes in the S1 subunit of the SARSCoV-2 spike protein. [ABSTRACT FROM AUTHOR]

Members of the genus Emaravirus are plant viruses transmitted by eriophyoid mites. The emaravirus genome consists of multiple, negative-sense, single-stranded RNA segments, that have been shown to be highly divergent. Recent studies have revealed that emaraviruses are associated with long-recognized diseases of world important crops such as fig mosaic disease or sterility mosaic disease of pigeon pea. Furthermore, along with the popularization of deep sequencing technologies, new putative members of emaraviruses have been reported year by year. This paper presents an overview of agricultural damages caused by emaraviruses worldwide and characteristics of their genomic RNAs and proteins. In addition, our research project to prevent a disease of a herb crop (shiso, Perilla frutescens) caused by Perilla mosaic virus, a putative emaravirus recently identified in Japan, is outlined.

Various DNA viruses are known to cause severe infectious diseases in both plants and mammals, including humans. For many of these infectious diseases, we have yet to find an effective prevention or treatment. Therefore, new methodologies for the prevention of virus infections in both agricultural crops and humans have been vigorously sought for a long time. One attractive approach to the prevention is inhibition of virus replication. We first inhibited virus replication by blocking binding of a viral replication protein, which initiates virus replication, to its replication origin, with using an artificial DNA-binding protein. We demonstrated that this new methodology was very effective in plants and mammalian cells: especially, we created transgenic plants that were immune to a geminivirus. We also developed novel protein-based antiviral drugs by fusing a cell-penetrating peptide to an artificial DNA-binding protein. Furthermore, we successfully generated a more effective protein-based antiviral, which was one hundred thousand times more active than the antiviral chemical drug Cidofovia, by alternatively fusing an DNA-cleaving enzyme to an artificial DNA-binding protein. Since this artificial protein has little cytotoxicity, it is expected that it will be used as a new antiviral drug.

Arenaviruses are the collective name for viruses, which belong to the family Arenaviridae. They replicate in the cytoplasm of cells, and were named after the sandy (Latin, arenosus) appearance of the ribosomes often seen in thin sections of virions under electron microscope. Several arenaviruses, such as Lassa virus in West Africa, and Junin, Guanarito, Sabia, Machupo, and Chapare viruses in South America, cause sever viral hemorrhagic fevers (VHF) in humans and represent a serious public health problem. These viruses are categorized as category 1 pathogens thus should be handles in a BSL4 laboratory. Recently, Lujo virus was isolated as a newly discovered novel arenavirus associated with a VHF outbreak in southern Africa in 2008. Although, we have no VHF patients caused by arenaviruses in Japan, except for a single imported Lassa fever case in 1987, it is possible that VHF patients occur as imported cases as for other VHF in the future. Therefore, it is necessary to develop the diagnostics and therapeutics in consideration of patient's severe symptoms and high mortality even in the disease-free countries. In this review, we will broadly discuss the current knowledge from the basic researches to diagnostics and vaccine developments for arenavirus diseases.

Influenza A viruses of 16 serologically different hemagglutinin (HA) subtypes have been identified in waterfowl reservoirs, and the introduction of a novel HA subtype of avian viruses into the human population has the potential to generate the next pandemic strains. Both humoral and cellular immunity play important roles against influenza virus infection. Currently available inactivated influenza vaccines primarily induce subtype-specific serum neutralizing antibodies, but not cross-reactive cytotoxic T-cell response. Thus, vaccine-induced immunity is not fully effective against strains with serologically distinct HA. Our long-term goal is to develop a vaccine/therapy to induce highly crossreactive anti-influenza immunity, which may lead to the establishment of an ultimate strategy for the control of influenza.

In the spring of 2009, a novel swine-origin H1N1 virus, whose antigenicity is quite different from those of seasonal human H1N1 strains, emerged in Mexico and readily transmitted and spread among humans, resulting in the first influenza pandemic in the 21st century. Molecular analyses of the pandemic H1N1 2009 viruses indicate low-pathogenic features for humans, although worldwide transmission of the virus and a considerable numbers of lethal cases with acute pneumonia have been observed in the first wave of the current pandemic. Here, we review our current molecular knowledge of transmissibility and pathogenicity of influenza viruses and discuss the future aspects of the pandemic virus.

In the spring of 2009, a novel swine-origin H1N1 virus, whose antigenicity is quite different from those of seasonal human H1N1 strains, emerged in Mexico and readily transmitted and spread among humans, resulting in the first influenza pandemic in the 21st century. This novel H1N1 virus was shown to be a triple reassortant comprising genes derived from avian, human, and swine viruses. Here, we review our current knowledge of this pandemic influenza virus and discuss future aspects of the pandemic.

Human norovirus is a mutatable non-enveloped RNA virus capable of causing acute gastroenteritis in humans. Thus far, no experimental systems can propagate this virus in large amounts. Recent progresses in viral genomics and bioinformatics have led to a better understanding of molecular evolution of this virus in human populations. In addition, progresses in studies of the related noroviruses, those are replicable in laboratory systems, have led to a rapid accumulation of information on structural biology of norovirus. Furthermore, progresses in public health and water environment researches have led to a better understanding of viral ecology. In this review, I will first summarize fundamental characteristics of norovirus and its molecules. Then, I will summarize structure and molecular evolution of norovirus GII/4 subtype, which is now responsible for majorities of norovirus outbreaks in the world. Finally I will discuss survival strategies of human norovirus in nature by integrating the information.

Severe acute respiratory syndrome (SARS) is an emerging disease derived from wild animals and is highly pathogenic with a high mortality. A novel coronavirus SARS coronavirus was identified to be a causative agent for SARS. Since its discovery, many trials have been executed to establish the prophylactic and therapeutics toward SARS using laboratory animals. A number of different types of vaccines, such as inactivated virus vaccine, subunit vaccine, DNA vaccine and vaccine using viral expression vector as well as attenuated live vaccine so far reported indicate that neutralizing antibodies play an important role for protection. However, vaccine applicable to humans with the high efficacy and safety has not yet been reported.

Lipoid pneumonia usually presents after chronic recurrent ingestion of oily substances or accidental aspiration during "fire-eating" demonstrations. Massive exposure by near drowning extremely rare and potentially fatal. We present here a case of survival after total immersion in oil in her workplace. A 66-year-old woman who nearly drowned in a vat of vegetable oil was admitted as an emergency case with severe hypoxia after rescue. Chest computed tomography (CT) findings showed bilateral ground-glass opacity, consolidation, and the case fulfilled the criteria for acute respiratory distress syndrome (ARDS). Bronchoscopy and bronchoalveolar lavage performed on admission indicated oil droplets and marked neutrophilia (67%), which made us diagnose ARDS induced by lipoid pneumonia. We commenced treatment with pulsed steroids and strictly managed fluid balance under mechanical ventilation. Despite immediate improvement in oxygenation, the value of extravascular lung water index (EVLWI) measured by the PiCCO system consistently remained over 30 ml/Kg through her clinical course. We concluded that lipoid pneumonia is characterized by prolonged elevatation of pulmonary vascular permeability.

In order to establish infection to host cells, viruses suppress or escape from the host immune response against microorganisms by various strategies. Interferon (IFN) system is an important contributor of innate immunity. IFN is induced by viral infection, and it promotes antiviral state through induction and/or activation of the effector molecules. Many viruses possess the suppression or inhibition mechanisms for the anti-viral effector molecules, whereas they also perform inhibition of IFN signaling pathway, JAK/STAT pathway. We consider that latter is a most effective strategy counteracting IFN function, because the signaling pathway is an entrance of the system. The strategies counteracting JAK/STAT pathway are varied among virus species. Viruses perform (i) production of IFN-binding protein, (ii) degradation of JAK/STAT components, (iii) suppression of activation (phosphorylation) of the components, (iv) inhibition of nuclear translocation of activated transcription factor, and (v) induction of host JAK/STAT negative regulator. Here, we present these strategies, especially our recent resulta of HSV1, mumps virus, and measles virus. For example, HSV1 induces a host JAK/STAT negative regulator SOCS3 (suppressor of cytokine signaling-3). Mumps virus V protein promotes degradation of both STAT-1 and STAT-3. Measles virus freezes the flexibility of IFN-alpha receptor complex by the action of viral proteins, C and V.

Fas-Fas ligand interactions between adenovirus-infected hepatocytes and cytotoxic T lymphocytes (CTLs) play a major role in killing of vector-transduced hepatocytes. Cytokine response modifier A (CrmA) is known to protect lymphoid cells from Fas-mediated apoptosis by inhibiting caspase 8. In this study, we generated an E1-deleted adenovirus expressing CrmA, and investigated the effect of exogenous CrmA expression on the inhibition of Fas-mediated apoptosis in murine hepatocytes in vitro and on the prolongation of the transgene expression in adenovirus-transduced hepatocytes in vivo. Agonistic anti-Fas antibody induced massive apoptosis into hepatocytes, however, most of the cells expressing CrmA were escaped from apoptosis and survived. This result showed that anti-apoptic function was obtained in murine hepatocytes by expressing CrmA. The prolongation of the transgene expression was studied using mice with congenital deficiency of lysosomal beta-glucuronidase (GUSB). The serum GUSB activity from the mice injected only an adenovirus expressing human beta-glucuronidase disappeared within 70 days, however, significant GUSB activity was observed for more than 130 days in the mice co-transduced with adenoviruses expressing both GUSB and CrmA. Moreover, histochemical analysis showed GUSB expressions in the liver even at 130 days after the viral administration. These observations demonstrate that the prolongation of the transgene expression can be achieved in rodent liver by CrmA co-expression using adenoviral gene transfer.

Syntheses of nucleic acids are of importance not only in the natural product chemistry but also in the molecular recognition study in biology. This review describes syntheses of RNA and DNA, which were found to be related each other. Deoxyinosine probes were developed for cloning genes with degenerated codons. Synthetic genes for c-Ha-ras and T4 endonuclease V provided new approaches in recognition of nucleic acids by proteins. Antibodies specific for photo-damaged pyrimidines in DNA have been studied by cloning and mutating their genes.

Purpose: To control exogenous gene expression is an important norm in human gene therapy. We attempted to control lac Z gene expression in a rabbit corneal stromal cell (RCS) culture system with recombinant adenovirus (Ad) and the Cre/loxP system., Materials & Methods: The RCS was transfected with an Ad which expressed the lac Z gene by excisional deletion of stuffer DNA, Ax CA LNLZ. Four days after the transfection, the cells were also transfected with a Cre-producing Ad, Ax CA NCre., Result: Few cells (0.8%) of the RCS transfected with Ax CA LNLZ expressed the lac Z gene. After the transfection of Ax CA NCre, all cells strongly expressed the lac Z gene. This result showed that recombinant adenovirus using the Cre/loxP system was capable of controlling exogenous gene expression in cultured rabbit corneal stromal cells., Conclusion: We suggest that recombinant adenovirus using the Cre/loxP system is useful for studying ophthalmic gene therapy.

The ganciclovir(GCV)-resistant human cytomegaloviruses(HCMV) result from the mutation(s) in either the UL97 phosphotransferase gene, or UL54 DNA polymerase gene, or both. Majority of clinical isolates of GCV-resistant mutant had mutations in the UL97 gene. Because the mutations in the UL97 gene cluster in two regions, sudomain VI and IX, it is almost possible to identify a GCV-resistant mutant by PCR-based DNA analysis. On the contrary, only a few mutants which had mutation(s) in the UL54 DNA polymerase have been analyzed. Therefore, to establish the system which identifies the mutation in UL54 DNA polymerase gene, the more analysis of this type of mutants is required.

Gene targeting in ES cells is a powerful tool to generate mice bearing predesigned mutations in the germ line. However, these mice carrying such constitutional mutations are often lethal and, therefore, we cannot study other functional aspects of the gene at later stages or in particular tissues. To inactivate the target gene in particular tissues or at particular stages of development, conditional gene inactivation based on the Cre-loxP recombination system of bacteriophage P1 is considered one of the applicable techniques. To express the Cre gene in a cell-type or developmental stage specific manner, either transgenic or adenoviral technology is most considerable technique in vivo.

Tumor cells undergo apoptotic cell death when treated with several chemotherapeutic agents. Since these agents, acting on different cellular targets, induce a similar pattern of cell death (apoptosis), it is suggested that a common signaling pathway of apoptosis could exist and that apoptosis resistance could cause a new form of multi-drug resistance in tumor cells. Although the mechanisms of apoptosis are not fully understood, the involvement of ICE/ced-3 family proteases in chemotherapy-induced apoptosis is strongly suggested. Identification of factors directly acting on these apoptosis pathway will offer new strategies in cancer chemotherapy.

To elucidate the mechanism of apoptosis in brain tumors, we analyzed the expression of apoptosis-related gene products in cultured glioma cells and biopsied brain tumor specimens. Fas, Bcl-2 family (Bcl-2, Bcl-x and Bax) and ICE family (ICE, Ich-1) were found to be involved in tumorigenesis of certain brain tumors. It was also clarified that OK-432 activated mononuclear cells could kill T98G glioblastoma cells by apoptotic mechanism through the Fas ligand/Fas system.