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Purpose:Coronavirus disease (COVID-19) has been declared a pandemic and the number of infected individuals and deaths continue to increase globally. COVID-19 is transmitted through airborne droplets formed during coughing and sneezing and from the saliva of infected patients. Medical healthcare workers are often at risk of infection. This study measured the aerosol derived from the droplets of patients during the conversation.Methods:Overall, 25 patients aged 21 to 87 years were enrolled. The amount of droplets from the patient was measured under the following four conditions: 1) no conversation with the mask on; 2) conversation with the mask on; 3) conversation without the mask; and 4) no conversation without the mask. Particulate matter (PM) with an aerodynamic diameter of 2.5 μm or less (PM2.5) and PM with a diameter of 10 μm or less (PM10) were measured as representative aerosols at a position of 1 meter from the patients.Results:The concentrations of PM2.5 (µg/m3) were as follows: 22.7 ± 10.2 before the conversation with the mask, 24.2 ± 10.2 during the conversation with the mask, 32.3 ± 14.7 during the conversation without the mask, and 23.1 ± 9.9 after the conversation without the mask. The concentrations of PM10 (µg/m3) were as follows: 39.8 ± 18.2 before conversation with the mask, 41.9 ± 18.5 during conversation with the mask, 55.5 ± 27.2 during conversation without the mask, and 40.4 ± 17.8 after conversation without the mask. The variations in the PM2.5 and PM10 correlated negatively with the age of patients (PM2.5: r = -0.51, p = 0.0009 and PM10: r = -0.53, p = 0.0063).Conclusion:Wearing a mask can prevent airborne droplet formation and reduce transmission of infection.

Purpose It has been proven that wearing soft contact lenses (SCLs) can make pollen-induced allergic conjunctivitis worse. We investigated the cleaning effect of disinfectants and rinsing solution on cedar pollen attached to SCLs. Methods Two-week replacement disposable SCLs, to which pollen particles were experimentally attached, were washed and cleaned with either saline of rinsing solution (n = 10) or 3% hydrogen peroxide (n = 10). We observed, under a microscope, the cedar pollen adhered to the SCLs after washing. Results The number of residual pollens attached to SCLs was 23.7 ± 25.7 with rinsing solution and 0.2 ± 0.6 with 3% hydrogen peroxide solution per single area (100 µm × 100 µm). The percentage of adhesion area of pollen to the SCLs was 0.9 ± 1.1% with rinsing solution and 0.0 ± 0.0% with 3% hydrogen peroxide solution. There were significant differences in the number of pollen and adhesion areas of pollen between the two groups (p < 0.05 and p < 0.05, respectively). Conclusion These results suggest that hydrogen peroxide solution is superior in cleaning effect of cedar pollen attached to SCLs compared to saline.

Tatsuya Mimura,1 Hiroshi Fujishima,2 Eiichi Uchio,3 Kazumi Fukagawa,4,5 Makoto Kawashima,1 Kazuma Kitsu,1 Hiroaki Horikawa,1 Atsushi Mizota1 1Department of Ophthalmology, Teikyo University School of Medicine, Tokyo, Japan; 2Department of Ophthalmology, Tsurumi University School of Dental Medicine, Yokohama, Kanagawa, Japan; 3Department of Ophthalmology, Fukuoka University School of Medicine, Fukuoka, Japan; 4Ryogoku Eye Clinic, Tokyo, Japan; 5Department of Ophthalmology, Keio University School of Medicine, Tokyo, JapanCorrespondence: Tatsuya Mimura Tel +81-3-3964-1211Fax +81-3-3964-1402Email mimurat-tky@umin.ac.jpPurpose: Pollen and proteins attached to soft contact lenses (SCLs) exacerbate allergic conjunctivitis. The material of SCLs may affect the pollen adhesion to the SCLs. The factors associated with the number of pollen particles that are adherent to daily disposable SCL were investigated.Methods: Pollen particles were experimentally exposed to the contact lens surface of 12 types of SCLs for 1 hour, and the SCLs were washed and rinsed with a physiological saline (n=10 for each SCL type). A total of 120 contact lenses were used in this study. The pollen particles attached to the SCL were observed and photographed under a microscope. The influence of the materials of the SCLs on the degree of pollen adhesion were investigated.Results: The number of residual pollen particles attached to SCLs was in the range from 0– 293/area of 200× 200 μm. Percentage of pollen adhesion area of the surface of the SCL was in the range from 0.01% to 3.25%. There were significant differences in both the number and adhesion area of pollen particles among the 12 types of SCLs tested (P< 0.0001 and P< 0.0001, respectively). The number of pollen particles adhered to SCLs was significantly higher in colored SCLs than clear SCLs (unpaired t-test, p< 0.001). The portion of pollen adhesion area was the lowest in the silicone hydrogel SCLs made with delefilcon-A (0.01 ± 0.02%).Conclusion: Pollen adhesion in daily disposable SCLs depends on the characteristics and materials of the SCLs and was high in colored SCLs and lowest in delefilcon-A silicone hydrogel SCL. These results suggest that colored SCLs are not preferred during pollen season.Keywords: daily soft contact lens, delefilcon-A, pollen, silicone hydrogel

The aim of this study was to clarify the relationship between dioxin concentrations in breast milk and the sister chromatid exchange (SCE) frequency in women from herbicide-sprayed and non sprayed areas. Blood samples were taken from 21 women with high TCDD (tetrachlorodibenzo-p-dioxin) levels from sprayed areas, 23 women with moderate TCDD levels from sprayed areas, and 19 women from non sprayed areas to determine their SCE frequency. The SCE frequencies for the high and moderate TCDD groups from the sprayed area and for the non sprayed area group were 2.40, 2.19, and 1.48 per cell, respectively. Multiple regression analysis showed that the standardized β values for 1,2,3,6,7,8-hexaCDD (β = 0.60), 1,2,3,4,6,7,8-heptaCDD (β = 0.64), and octaCDD (β = 0.65) were higher than those for TCDD (β = 0.34) and 1,2,3,7,8-pentaCDD (β = 0.42). The adjusted R2 value for polyCDDs (R2 = 0.38) was higher than that for polyCDD toxic equivalents (TEQ (toxic equivalents), R2 = 0.23). This study therefore shows that levels of hexa-, hepta-, and octaCDD, which were previously regarded as being less toxic than TCDD, are closely related to SCE frequency and that the level of dioxin (pg/g lipid) is potentially more useful as an indicator than TEQ value for explaining SCE frequency.

Copper mediated alkyl-transfer reaction of trialkylaluminum (R 3 Al) with ( E )-4,4-difluoro-5-hydroxyallylic alcohol derivative smoothly proceeded to give the corresponding 2-alkylated 4-fluoro-5-hydroxyhomoallylic alcohol derivative with completely Z and 2,5- syn selective manner. Regio- and stereoselective conversion of the C5-hydroxyl group of the fluoroolefin thus obtained to amino group could be achieved through one-pot mesylation and azidation reaction.

Carbocyclization of terminally difluorinated 3-butenyl active methine compounds 1a–1e proceeded through the 5-endo mode, upon treating with SnCl4 and triethylamine to give fluorocyclopentene derivatives 3a–3e. Iodocarbocyclization of dimethyl 2-(4,4-difluorobut-3-enyl)malonate (1a) mediated by I2, SnCl4 and amine provided 2,2-difluoro-3-iodocyclopentane-1,1-dicarboxylate 4a through the 5-endo mode, while in the case of 2-(5,5-difluoropent-4-enyl)malonate (1f) 5-exo mode cyclization reaction took place to give difluoroiodomethylcyclopentane derivative 5f.

The chemical properties of Amadori compounds in the presence of transition metal ions were studied, using the analogs 1-deoxy-1- n -butylamino- d -fructose (DBF) and N &#102 -formyl-fructoselysine (fFL). The following characteristics were revealed: (a) DBF combined easily with Cu 2+ (but no other transition metal ions) to form a DBF-Cu 2+ complex in phosphate buffer, pH 7.4; (b) the complex was unstable, and degraded with the release of Cu + during incubation at 37°C; (c) degradation of the complex was associated with the production of hydroxyl radicals by the Fenton reaction and &#102 -dicarbonyl compounds by non-autoxidative degradation; and (d) properties of DBF were similar to those of fFL. The above properties were additionally observed in glycated poly-Lys (GPL). Our findings indicate a novel mechanism for the generation of hydroxyl radicals and &#102 -dicarbonyl compounds from Amadori adducts in the presence of Cu 2+ .

Preparation of methylenedifluorocyclopropanes 2 through the β-elimination reaction promoted by difluorocyclopropyl anion formed by cleavage of CSi bond with TBAF is described. Base-catalyzed isomerization of 2 to difluorocyclopropene 11 shows the latter structure themodynamically more stable in contrast to non-fluorinated cases. Application of this method to the synthesis of methylenedifluorocyclo-propylglycine (F2MCPG) derivative 17 is also presented.

Fluoro-lactonization of 4-alkenoic acid derivatives containing an aryl substituent at the 4- or 5-position with N-fluoropentachloropyridinium triflate proceeds smoothly in a regioselective manner with little or no diastereoselectivity. These reactions possibly involve aryl-stabilized αfluorocarboc intermediates formed via single electron transfer from the pyridinium salt to the olefin as the first step.

By dye leakage in mouse skin, we evaluated the inhibition of proinflammatory stimuli-induced plasma extravasation by a putative inhibitor of inducible nitric oxide synthase, S-ethylisothiourea. A low dose of S-ethylisothiourea (5 micrograms/kg) mimicked aminoguanidine in inhibiting the plasma extravasation elicited by lipopolysaccharide but not by 5-hydroxytryptamine or platelet-activating factor. A higher dose of S-ethylisothiourea (10 micrograms/kg) inhibited the plasma extravasation induced by 5-hydroxytryptamine slightly; however, it increased the basal dye leakage. Thus, S-ethylisothiourea may be used as a relatively specific inhibitor for inducible nitric oxide synthase in vivo.

Cu(I)-mediated alkyl-transfer reaction of trialkylaluminum (R 3 Al) with ( E )- or ( Z )-4,4-difluoro-5-hydroxyallylic alcohol derivatives proceeded in an SN′-type manner to give the corresponding 2-alkylated ( Z )-4-fluoro-5-hydroxyhomoallylic alcohol derivatives with 2,5- syn - or 2,5- anti selectivity, respectively. Oxidation of the primary hydroxyl group of the product to carboxylic acid was easily achieved without epimerization at the chiral centers.

Fluoro-lactonization of 4-alkenoic acid derivatives containing an aryl substituent at the 4- or 5-position with N-fluoropentachloropyridinium triflate proceeds smoothly in a regioselective manner with little or no diastereoselectivity. These reactions possibly involve aryl-stabilized αfluorocarboc intermediates formed via single electron transfer from the pyridinium salt to the olefin as the first step.

Preparation of methylenedifluorocyclopropanes 2 through the β-elimination reaction promoted by difluorocyclopropyl anion formed by cleavage of CSi bond with TBAF is described. Base-catalyzed isomerization of 2 to difluorocyclopropene 11 shows the latter structure themodynamically more stable in contrast to non-fluorinated cases. Application of this method to the synthesis of methylenedifluorocyclo-propylglycine (F2MCPG) derivative 17 is also presented.

Cu(I)-mediated alkyl-transfer reaction of trialkylaluminum (R 3 Al) with ( E )- or ( Z )-4,4-difluoro-5-hydroxyallylic alcohol derivatives proceeded in an SN′-type manner to give the corresponding 2-alkylated ( Z )-4-fluoro-5-hydroxyhomoallylic alcohol derivatives with 2,5- syn - or 2,5- anti selectivity, respectively. Oxidation of the primary hydroxyl group of the product to carboxylic acid was easily achieved without epimerization at the chiral centers.

1) 非酵素的糖付加反応によって修飾されたウシ血清アルブミンはEx max 350nm, Em max 430nmの蛍光特性を示した。2) ヒトの新鮮血液から分離したアルブミンはEx max 346nm, Em max 450nmの蛍光特性を示した。この血漿にグルコースを加えてインキュベーションすると糖濃度に依存して蛍光強度は増加し, 同時にEm maは450nmから430nmへ, シフトした。これらの蛍光はMaillard反応の後期段階の生成物によるものと思われる。3) ヒト血清アルブミンのmg当りの蛍光強度 (Ex 346nm, Em 450nm) は糖尿病患者群 (n=18) では健常者群 (n=10) に比べて有意 (p

δ-Fluoro and δ,δ-difluorohomoallylic alcohol derivatives can be efficiently prepared by LiAlH 4 reduction of the δ,δ-difluoroallylic alcohols and the γ-chlorodifluoromethylallylic alcohols, respectively, through regioselective SN2′ reaction, in which the free hydroxyl group is essential for the reaction to proceed.

Reaction of γ,γ-difluoro-α,β-enoates having a δ-hydroxyl group with trialkylaluminum (R3Al) in the presence of CuI•2LiCl proceeded in SN2′-type manner to give α-alkylated (Z)-γ-fluoro-β,γ-enoates, while reductive defluorination of γ,γ-difluoro-α,β-enoates with Me2CuLi followed by reaction with alkyl halides provided the corresponding (Z)-α-alkylated products.

カフェ酸エチルエステルによるアミノ酸, タンパク質の緑色反応の特色とこの反応によるタンパク質の測定法について検討した。1. 呈色度アミノ酸の種類により異なった。芳香族アミノ酸やヒスチジンは強く呈色したがパリン, イソロイシンおよびセリン, スレオニンの呈色は弱かった。また, プロリンやシスティンは反応しなかった。一方, ペプチド末端のαアミノ基による呈色は弱かったがリジン残基のeアミノ基による呈色はかなり強かった。2. λmax多くのアミノ酸はおおむね680～690nmにλmaxを示したが芳香族およびイミダゾール環をもつアミノ酸は長波長側 (695～700nm) にあり, リジン, オルニチンおよびωアミノ酸では短波長側 (675～676nm) に位置し, それぞれλmaxに特徴が見られた。3. 反応温度アルブミンでは70℃, アミノ酸では60℃が最適温度であり, それ以上の温度では緑色調が減少し褐色調が増大した。4. αケト酸の影響アルブミン, アミノ酸いずれの場合もαケト酸存在下で反応の促進が見られた。促進効果はピルビン酸>αケトグルタル酸>オキザロ酢酸の順であった。βフェニルピルビン酸は本反応を阻害し, 反応液は褐色を呈した。5. タンパク質の定量性ウシ血清アルブミンは0.2～1.0mgの範囲で呈色度が直線的に増加した。さらに, ヒト希釈血清を用いて本法およびBiuret法によるタンパク質測定値間の相関を求めたところ高い相関性 (r=0.995) が認められた。

The studies on the mechanism of greening resulted from the chemical reaction of chlorogenic acid or its related compounds with amino acids, peptides or proteins had been carried out by URITANI et. al in detail. But the chemical structure and properties have not been elucidated yet. So the authors tried to make clear these problems.The green solution was prepared from the mixture of chlorogenic acid and L-phenylalanine by two methods of oxidation, polyphenoloxidase in the presence of air and only air. Each green solution prepared was treated by Sephadex G-25 and fractionated into three color bands (brown, green and blue-purple), respectively. Of these, the green and blue-purple fractions were purified and powdered by acetone treatment. In this paper, the method of fractionation and some chemical properties of the powdered pigments are described.

Oxidations of epigallocatechin in the presence of catechol or pyrogallol with tea oxidase as well as with an oxidizing reagent and the isolation of the oxidation products, categallin (II) and pyrogallin (III), in crystalline form are described. Their absorption spectra are compared with those of pigment P(I) obtained by the oxidation of epigallocatechin and epicatechin, and their structural relationships are discussed.

A study is made on the oxidation of a mixture containing epigallocatechin and epicatechin with tea oxidase as well as a oxidizing reagent, in order to understand the formation of red pigments in tea manufacture. As the reaction proceeds a remarkable colored substance is formed, which can be obtained in reddish orange needles (from water) and is supposed to be a troponoid compound having a 3′,4′-dihydroxybenzotropolone nucleus as suggested by a tentative structural formula III from a consideration of its spectral characteristics.