Elucidation of electromagnetic wave effect and outgoing of future trend in microwave Chemistry and Biology

[EN] Can we use microwaves as electromagnetic energy in the chemical and biological fields? We have been researching this question in many aspects and in a bird's-eye view. In response to this question, in some chemical reactions, it turned out that the advantage of microwaves is heat. Note that we also found that this efficient thermal energy transfer method is useful in the chemical field. On the other hand, it was found that electromagnetic waves other than thermal energy can be used in limited chemical reactions (mainly radical reactions). On the other hand, in biological use, there are not many things that require more heat energy than the atmosphere in the first place. However, we have found that depending on the microwave irradiation conditions, it can be activated as a stimulus other than heat. In other words, we discovered a phenomenon that would not have appeared without microwaves. In this paper, it will explain the electromagnetic wave effects of microwaves using photocatalysts, enzymes, and plants as examples. Furthermore, the importance of microwave control will be explained from the development of intelligent cooker.Horikoshi, S. (2019). Elucidation of electromagnetic wave effect and outgoing of future trend in microwave Chemistry and Biology. En AMPERE 2019. 17th International Conference on Microwave and High Frequency Heating. Editorial Universitat Politècnica de València. 13-25. https://doi.org/10.4995/AMPERE2019.2019.9783OCS132

Development of a Hg-free UV light source incorporating a Kr/Br 2 gas, and its application for wastewater treatments

Mercury lamps are typically the major light sources in water treatments. However, the use of mercury has raised some concerns with regard to the Minamata Convention on Mercury. As such, Hg-free microwave discharged electrodeless lamps (MDELs) that incorporate a rare gas and a halogen gas (R/H-MDEL) have been investigated with such Hg-free mixture filler gases as Kr/Cl2, Xe/Cl2, and Kr/Br2 (R/H). Of these, only the Kr/Br2-MDEL lamp is self-ignited at an inner pressure of 15 Torr when irradiated with microwave radiation. Accordingly, a novel Kr/Br2 three-layer MDEL (Kr/Br2-MDEL) photoreactor was fabricated to assess the optimal gas composition and gas pressure toward its performance vis-a-vis the treatment of model wastewaters contaminated with the tartrazine dye in aqueous media and with Escherichia coli (E. coli) bacteria. The extent of degradation of the tartrazine dye and sterilization of E. coli increased with irradiation time, with microwave radiation power (100, 200, and 300 W), and with increased sample flow rate 0.4 L min‒1 to 0.8 L min‒1. The tartrazine-contaminated wastewater was treated at a flow rate of 0.4 L min‒1 for 60 min of microwave irradiation by three different protocols that resulted in UV (62%) >> UV/ROS (24%) > ROS (0%); ROS denotes reactive oxygen species. After 5 min irradiation of the E.coli wastewater, also at 0.4 L min‒1, the order was UV (99.5%) ≈ UV/ROS (99.3%) >> ROS (14.5%). For comparison, the photosterilization of E. coli with an equivalent Hg/Ar-MDEL light source was also nearly complete (99.7%). Thus, the suitability of the environmentally friendlier Kr/Br2 gas fill to replace Hg/Ar filler gas in MDELs for the photoelimination of organic pollutants and microbial disinfection in aqueous media has been demonstrated

In-liquid plasma using microwave power for applications

[EN] The research of in-liquid plasma that uses microwave as an energy source can be generated without depending on the electric conductivity of the solution, so it has wide application. However, it is not practical because the microwave antenna (plasma electrode) is deteriorated immediately. We were noticed that the microwave is pulsed to solve this problem. In this study, its optimum conditions was investigated. The best parameters of pulse microwave power was investigated using the generator (peak power ; 380 W, pulse width ; 13.4 msec and pulse duty cycle ; 16.7 msec). Stable in-liquid plasma could be generated in this conditions. This optimised system of in-liquid plasma tried to use applications for wastewater treatment and gel synthesis. In first application (wastewater treatment), tetrabromobisphenol A (TBBPA) was ionized and minerated by using in-liquid plasma method for only 20 min, respectivily. In second one (gel synthesis), in-liquid plasma can synthesize gel-synthesis without crosslinking agent and initiator. This new method could synthesize gel of dimethyl polysiloxane (silicone) and polyvinilypirroridone (PVP) without both crosslinking agent and initiator, it suggested that in-liquid plasma method is effective as a green chemistry process.Sawada, S.; Horikoshi, S. (2019). In-liquid plasma using microwave power for applications. En AMPERE 2019. 17th International Conference on Microwave and High Frequency Heating. Editorial Universitat Politècnica de València. 59-66. https://doi.org/10.4995/AMPERE2019.2019.9815OCS596

Rapid Synthesis of highly luminescent Carbon Quantum Dots using Low-Pressurized Microwave Solvothermal Heating

[EN] In this research, we ameliorated the problems of carbon quantum dots synthesis and luminescence (quantum yields) by the novel synthesis protocol using microwave chemistry. Specifically, we synthesized high quantum yields carbon quantum dots (61%) by utilizing a microwave chemical synthesis, synthesizing at low pressure condition (lower than 5 atom) and short reaction time (3 hrs). The achievement of this high quantum yields made it clear that the contribution of polyethylene glycol (PEG) shell to carbon quantum dots is large. It was confirmed from the DLS and TEM image that the particle size of the synthesized particles was 8 to 13 nm. On the other hand, the relationship between the polymerization degree of added PEG and the quantum yields to the addition amount is summarized. The quantum yields of carbon quantum dots without addition of PEG was 16.7 %, while it was improved at 61.1 % when 0.6 g of PEG 6000 (Molecular weight: 6000) was added. Furthermore, we compared microwave with conventional method, and it was revealed that higher luminescent and narrower sized carbon quantum dots were synthesized in microwave heating than conventional method. This result presumably comes from the nature of microwave selective heating of carbon precursor.Hagiwara, K.; Horikoshi, S. (2019). Rapid Synthesis of highly luminescent Carbon Quantum Dots using Low-Pressurized Microwave Solvothermal Heating. En AMPERE 2019. 17th International Conference on Microwave and High Frequency Heating. Editorial Universitat Politècnica de València. 388-393. https://doi.org/10.4995/AMPERE2019.2019.9784OCS38839

Effect of NK-104 on proliferation of cells

AbstractObjectiveProducts of intracellular mevalonate metabolism are essential for cell growth and proliferation. Inhibition of mevalonate synthesis by statins has been shown to suppress mesangial cell proliferation associated with various glomerular diseases. In this study, we investigated the effect of a new synthetic 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, NK-104, on cultured rat mesangial cell proliferation.MethodsThe cultured rat mesangial cells were stimulated by 10% fetal calf serum or platelet-derived growth factor in the absence or presence of NK-104 and mevalonate metabolites. 5-bromo- 2-deoxyuridine incorporation was used to assess DNA synthesis. In other experiments, Ras processing and mitogen-activated protein kinase activation were analyzed by Western blotting.ResultsNK-104 inhibited fetal calf serum- or platelet-derived growth factor-stimulated Ras processing and mitogen-activated protein kinase activation. NK-104 also caused inhibition of fetal calf serum- or platelet-derived growth factor-stimulated 5-bromo-2-deoxyuridine incorporation and cell proliferation. Mevalonic acid, farnesyl pyrophosphate, and geranylgeranyl pyrophosphate significantly prevented these inhibitory effects of NK-104.ConclusionThe present results suggest that NK-104, by inhibiting the synthesis of isoprenoid metabolites of mevalonate, may modulate Ras-mediated signaling events associated with mesangial cell proliferation

Different Pathological Roles of Toll-Like Receptor 9 on Mucosal B Cells and Dendritic Cells in Murine IgA Nephropathy

Although pathogenesis of IgA nephropathy (IgAN) is still obscure, pathological contribution of mucosal immunity including production of nephritogenic IgA and IgA immune complex (IC) has been discussed. We have reported that mucosal toll-like receptor (TLR)-9 is involved in the pathogenesis of human and murine IgAN. However, cell-type expressing TLR9 in mucosa remains unclear. To address this, we nasally challenged cell-specific CpG DNA ((i): dendritic cell: (DC), (ii): B cell, (iii): both), known as ligand for TLR9, to IgAN prone mice and analyzed disease phenotype of each group. After 8 times of the weekly administration, every group showed deterioration of glomerular damage. However, CpG-A-group showed clear extension of mesangial proliferative lesions with increase of serum IgA-IgG2a IC and its glomerular depositions, while CpG-B-group showed extent of glomerular sclerotic lesions with increase of serum and glomerular IgA and M2 macrophage infiltration. Present results indicate that mucosal TLR9 on B cells and DC may differently contribute to the progression of this disease via induction of nephritogenic IgA or IgA-IgG IC, respectively. This picture is suggestive for the pathological difference between child and adult IgAN

Subfossil Land Snail Fauna (Mollusca) of Central Chichijima, Ogasawara Islands, with Description of a New Species.

v. ill. 23 cm.QuarterlyThe fossil record provides useful information to estimate what island communities were like before human colonization. We examined the species composition of the subfossil land snail fauna of dune deposits at the Yatsuse River, central Chichijima, Ogasawara Islands, and compared it with the species recorded in Chichijima since the nineteenth century. The 22 species in the dune deposits included 13 species that are now extinct in Chichijima. Live specimens of 11 of these extinct species were recorded in the early twentieth century, but no living Mandarna pallasiana and Ogasawarana obtusa Chiba et al., n. sp., have ever been recorded. Age of the sediment, estimated by radiocarbon (14C) dating, was 720 years B.P., and it is possible that these two land snail species became extinct as a result of the impact of human colonization of the island, which started in 1830. Specifically, Ogasawarana obtusa, n. sp., became extinct before the start of taxonomic studies of the land snails of Ogasawara. The sample included Hawaiia minuscula, which is generally now considered a cosmopolitan species introduced from North America. This finding suggests that Hawaiia minuscula is not alien in Ogasawara but indigenous

Resting CD4+ T Cells with CD38+CD62L+ Produce Interleukin-4 Which Contributes to Enhanced Replication of T-Tropic Human Immunodeficiency Virus Type 1

AbstractA significant increase in the CD38+ population among T lymphocytes has been observed in human immunodeficiency virus type 1 (HIV-1)-infected carriers. We previously reported a higher replication rate of T-tropic HIV-1 in the CD4+CD38+CD62L+ than CD38− subset under conditions of mitogen stimulation after infection. Here, we revealed a similarly high susceptibility in the CD38+ subset on culture with conditioned medium containing Th2 cytokine, interleukin (IL)-4 that was produced endogenously from this subset on stimulation with mitogen or anti-CD3 antibody for 3 days. The contribution of IL-4 to the upregulated production of virus in the CD38+ subset was confirmed by culture of this subset with recombinant human IL-4. In contrast, the rate of replication in the CD38− subset was not augmented in the conditioned medium from either subset or with IL-4. However, there were no differences in the surface expression of IL-4 receptor or HIV-1 receptors CD4 and CXCR4 between the two subsets. Thus, the CD4+CD38+CD62L+ subset comprises a specific cell population secreting endogenous Th2 cytokine that contributes to the efficient production of T-tropic HIV-1 through upregulation at a certain stage of the viral life cycle, probably after the adsorption step