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A photometric method to determine molecular oxygen in water was developed. When manganese(II) is oxidized by oxygen under alkaline conditions, the presence of polyphosphate can prevent precipitation due to a coacervate reaction. The oxidized manganese later dissolves in acid to form a pink Mn(III) species, which has a stable UV/vis spectrum. Monitoring of the oxygen concentration based on the absorbance of the pink Mn(III) species at 517 nm showed a strong correlation with both the Winkler method and an optical sensor. As a result, the present method can measure not only dissolved oxygen, but also fine bubbles oxygen in in the water sample with high reliability (0 - 26 mg dm-3, r2 = 0.9995). During this process, no significant interference from nitrite or metal ions was observed. The accuracy of the measurement was steady at high temperatures of the water samples (≤ 363 K).

The bioartificial liver (BAL) device is an extracorporeal liver support system incorporating living hepatocytes. A major problem in BAL device development is to obtain a high number of functional cells. In this study, we focused on a genetically engineered mouse hepatoma cell line, Hepa/8F5, in which elevated liver functions are induced via overexpression of liver-enriched transcription factors activated by doxycycline (Dox) addition. We applied a three-dimensional culture technique using hollow fibers (HFs) to Hepa/8F5 cells. Hepa/8F5 cells responded to Dox addition by reducing their proliferative activity and performing liver-specific functions of ammonia removal and albumin secretion. The functional activities of cells depended on the timing of Dox addition. We also found that Hepa/8F5 cells in the HF culture were highly functional in a low rather than high cell density environment. We further fabricated an HF-type bioreactor with immobilized Hepa/8F5 cells as a BAL device. Although ammonia removal activity of this BAL device was lower than that of the small-scale HF bundle, albumin secretion activity was slightly higher. These results indicated that the BAL device with immobilized Hepa/8F5 cells was highly functional with potential to show curative effects in liver failure treatment.

Studies of Alzheimer’s disease are based on model mice that have been altered by transgenesis and other techniques to elicit pathogenesis. However, changes in the gut microbiota were recently suggested to diminish cognitive function in patients, as well as in model mice. Accordingly, we have created model mice of the human gut microbiota by transplanting germ-free C57BL/6N mice with fecal samples from a healthy volunteer and from an affected patient. These humanized mice were stably colonized and reproduced the bacterial diversity in donors. Remarkably, performance on Object Location Test and Object Recognition Test was significantly reduced in the latter than in the former at 55 weeks of age, suggesting that gut microbiota transplanted from an affected patient affects mouse behavior. In addition, metabolites related to the nervous system, including γ-aminobutyrate, taurine, and valine, were significantly less abundant in the feces of mice transplanted with microbiota from the affected patient.

The continuous and selective determination method of formaldehyde (HCHO) in ambient air using chemiluminescence method has been developed. The counter current flow tube was used to collect ...

We present an analytical method for dissolved oxygen based on the quantification of Mn(III) absorbance in a water sample. After Mn(II) reacts with the oxygen molecules in water, Mn(III) is formed and stabilized by hexa-metaphosphate under acidic conditions. The UV visible absorbance of Mn(III) is proportional to the oxygen concentration in the water sample. Compared to the Winkler method, the proposed method has the same accuracy (R = 0.9992 at 0 - 52 mg dm-3) but requires fewer reagents; furthermore, it does not involve titration. Interferences from nitrite and iodate were not observed. This procedure can be used to accurately and quickly determine the oxygen concentrations in different natural water sources, including seawater.

With increasing interest in understanding contribution of secondary organic aerosol (SOA) to particulate air pollution in urban areas, an exploratory study was carried out to determine levels of carbonaceous aerosols and polycyclic aromatic hydrocarbons (PAHs) in the City of Kuala Lumpur, Malaysia. PM2.5 samples were collected using a high-volume sampler for 24 h in several areas in Kuala Lumpur during the north-easterly monsoon from January to March 2019. Samples were analysed for water soluble organic carbon (WSOC), organic carbon (OC), elemental carbon (EC) and secondary organic carbon (SOC) in PM2.5 was estimated. Particle-bound PAHs were analysed using gas chromatography-flame ionization detector (GC-FID). Average concentrations of WSOC, OC and EC were 2.7 ± 2.2 (range of 0.63-9.1) µg/m3, 6.9 ± 4.9 (3.1-24.1) µg/m3 and 3.7 ± 1.6 (1.3-6.8) µg/m3, respectively, with estimated average SOC of 2.3 µg/m3, contributing 34% to total OC. The average of total PAHs was 1.8 ± 2.7 ng/m3. Source identification methods revealed natural gas and biomass burning, and urban traffic combustion as dominant sources of PAHs in Kuala Lumpur. To understand human health risk posed by PAHs, a deterministic screening health risk assessment was also conducted for several age groups including infant, toddler, children, adolescent and adult. The total concentration of BaPeq is 3.8 ng/m3, with the average of 0.29 (range of 0.001-1.6) ng/m3. Carcinogenic and non-carcinogenic risk of PAH species were well below the acceptable levels recommended by the USEPA. Future work is needed using long-term monitoring data to understand the origin of PAH contributing to SOA formation and to apply source-risk apportionment to know better the potential risk factors posed by the various sources in urban areas in Kuala Lumpur.

In this paper, ambient total suspended particulates (TSP) with a focus on humic-like substances (HULIS) are characterized based on intensive ground-based field samplings collected in Malaysia during non-haze and haze periods caused by peatland fires on the Indonesian island of Sumatra. Furthermore, concentrations of water-soluble organic carbon (WSOC) and carbon content of HULIS (HULIS-C) were determined, and fluorescence spectra of the HULIS samples were recorded by excitation emission matrix (EEM) fluorescence spectroscopy. The concentrations of WSOC and HULIS-C over the entire period ranged from 4.1 to 24 and 1.3 to 18 μgC m−3, respectively. The concentrations of WSOC and HULIS-C during the peatland fire-induced strong haze periods were over 4.3 and 6.1 times higher, respectively, than the average values recorded during the non-haze periods. Even during the light haze periods, the concentrations of WSOC and HULIS-C were significantly higher than their averages during the non-haze periods. These results indicate that peatland fires induce high concentrations of WSOC, particularly HULIS-C, in ambient TSP at receptor sites. EEM fluorescence spectra identified fulvic-like fluorophores at the highest intensity level in the EEM fluorescence spectra of the haze samples. A peak at excitation/emission (Ex/Em) ≈ (290–330)/(375–425) nm is also observed at high intensity, though this peak is normally associated with marine humic-like fluorophores. It is shown that a peak at Ex/Em ≈ (290–330)/(375–425) nm is not derived from marine sources only; furthermore, peatland fires are shown to be important contributors to HULIS around this peak.

Incense stick burning is one of casual household activity, especially in East and Southeast Asian countries, including Vietnam. In this study, nine incense stick types were collected from Vietnam and investigated the carbonyl emission profile. The result showed that in ten analyzed carbonyl compounds, propionaldehyde (3–84%, avg. 32%), acetaldehyde (8–90%, avg. 30%), and acetone (0–38%, avg. 9%) were the most abundant in terms of total weight emitted carbonyls, respectively. The fourth abundant aldehyde was HCHO (1–26%, avg. 8%). The concentration of formaldehyde (HCHO) in released smoke ranged from 46.65 ± 4.44 to 596.89 ± 279.17 μg/m3 (38.02 ± 3.62 to 486.46 ± 242.19 ppb). High concentration of these carbonyls can pose health risk. Therefore, the personal risk assessment of HCHO inhalation exposure was carried out by the burning simulation in a small unventilated room. The risk calculation showed that the cancer risk is 1.81 × 10−5, 24% higher than the base risk. However, the risk may be much higher.

Animal studies suggested that halogenated hydrocarbons such as 1,1-difluoroethane (DFE) sensitized myocardial tissues to catecholamines and might cause fatal arrhythmia. In this paper, we report a case of a fatality that was associated with DFE abuse, and quantified DFE concentrations in postmortem specimens using gas chromatography–mass spectrometry (GC–MS). Femoral vein blood, cardiac blood, and urine samples were taken from the autopsy for toxicological analysis. We have established a detailed procedure for quantification of DFE in human blood and urine by GC–MS and have presented its validation data. The concentrations of DFE in this case were 481, 591 and 201 µg/mL in femoral vein blood, cardiac blood and urine samples, respectively, which were much higher than those in previous cases measured by gas chromatography–flame ionization detection. Thus, in the absence of other remarkable autopsy findings, the cause of death was determined to be DFE intoxication. To the best of our knowledge, this is the first case report of quantification of DFE in human blood and urine specimens by GC–MS.

We characterize fine particulate matter (PM2.5) emitted from Indonesian peatland fires using ground-based source-dominated samplings of PM2.5 near peatland fire sources at two Regencies in Riau, Sumatra, Indonesia (number of samples = 13). Organic carbon (OC), elemental carbon, water-soluble OC (WSOC), the carbon content of humic-like substances (HULIS-C), and biomass burning tracers are determined. The carbon mass ratios of WSOC to OC (0.085 ± 0.015) and HULIS-C to WSOC (0.55 ± 0.085) are fairly constant and independent of the peatland fire sampling sites. By comparing diagnostic ratios using OC, WSOC, and HULIS-C at the peatland fire source and the receptor site (Malaysia) during peatland fire-induced haze periods, secondary WSOC and HULIS-C formation during transport from the source to the receptor site is highly possible. Interestingly, the mass ratio of syringic acid to levoglucosan (0.045 ± 0.0075) is fairly constant at Indonesian peatland fire sources. Because syringic acid is less stable than levoglucosan, this ratio is an aging indicator for Indonesian peatland fires at receptor sites. By comparing the mass fraction of each organic compound in the present study and previous studies, it is evident that the source profile for the coburning of peat with surface vegetation is significantly different compared with the burning of peat alone. Further knowledge of peat burning emissions is needed, particularly with respect to burning conditions, peat composition, and the effects of vegetative burning on peatland. Improved knowledge of these factors would lead to more reliable speciated emission inventories of Indonesian peatland fires, advancing chemical transport and radiative forcing modeling, as well as health risk assessment.

We have observed soft X-ray spectra from highly charged ions of seven different lanthanide elements with atomic numbers ranging from 60 to 70 in laser-produced plasmas (LPPs) using CO2 and Nd:YAG laser systems, the wavelengths of which are 10.6 μm and 1.064 μm, respectively. The spectral feature drastically changes between the two types of LPPs due primarily to the difference in opacity. Narrowband quasicontinuum features arising from n = 4–4 transitions, the centre wavelength of which systematically moves to shorter wavelength as the atomic number (Z) increases, are observed in the CO2 LPPs, accompanied by sharp peaks coinciding with the strongest resonance lines of Pd-like ions for lower Z elements. In contrast, the quasicontinuum bands are broader and smoother in the Nd:YAG LPPs, appearing with bands of n = 4–5 transitions on the shorter wavelength side. The results are also discussed based on comparisons with atomic structure calculations for ions with outermost 4d and 4f subshells.

Formaldehyde (HCHO) is an important component in tropospheric chemistry, but the study of HCHO in rainwater is limited. This is the first report of continuous measurement of HCHO in rainwater. HCHO in rainwater was continuously measured using a modified chemiluminescence method at Sakai City, Osaka, Japan. The continuous measurement was conducted in the 2018 rainy season (Baiu) of Japan. A total of 20 rain events have been observed, and the averaged HCHO concentration of each rain event was 0.13–2.75 μM. The maximum concentration was 9.91 μM. Diurnal variation of HCHO in rainwater showed the distinctively high concentration in nighttime and no correlation with local ambient gaseous HCHO, implying another source such as aqueous photoproduction and transportation rather than scavenging. The photo-irradiation experiment revealed that photoproduction of HCHO is one of the important sources of HCHO in rainwater with the maximum production rate of 2.43 μM h−1. Besides, the backward trajectory indicated that there could have a link with the air mass original location. Furthermore, microorganism activity can play a role as a sink of HCHO in rainwater that could consume HCHO with digestion rate up to 3.2 μM h−1.

With increasing interest in understanding the contribution of secondary organic aerosol (SOA) to particulate air pollution in urban areas, an exploratory study was carried out to determine levels of carbonaceous aerosols and polycyclic aromatic hydrocarbons (PAHs) in the city of Kuala Lumpur, Malaysia. PM2.5 samples were collected using a high-volume sampler for 24 h in several areas in Kuala Lumpur during the north-easterly monsoon from January to March 2019. Samples were analyzed for water-soluble organic carbon (WSOC), organic carbon (OC), and elemental carbon (EC). Secondary organic carbon (SOC) in PM2.5 was estimated. Particle-bound PAHs were analyzed using gas chromatography-flame ionization detector (GC-FID). Average concentrations of WSOC, OC, and EC were 2.73 ± 2.17 (range of 0.63–9.12) µg/m3, 6.88 ± 4.94 (3.12–24.1) µg/m3, and 3.68 ± 1.58 (1.33–6.82) µg/m3, respectively, with estimated average SOC of 2.33 µg/m3, contributing 34% to total OC. The dominance of char-EC over soot-EC suggests that PM2.5 is influenced by biomass and coal combustion sources. The average of total PAHs was 1.74 ± 2.68 ng/m3. Source identification methods revealed natural gas and biomass burning, and urban traffic combustion as dominant sources of PAHs in Kuala Lumpur. A deterministic health risk assessment of PAHs was conducted for several age groups, including infant, toddler, children, adolescent, and adult. Carcinogenic and non-carcinogenic risk of PAH species were well below the acceptable levels recommended by the USEPA. Backward trajectory analysis revealed north-east air mass brought pollutants to the studied areas, suggesting the north-easterly monsoon as a major contributor to increased air pollution in Kuala Lumpur. Further work is needed using long-term monitoring data to understand the origin of PAHs contributing to SOA formation and to apply source-risk apportionment to better elucidate the potential risk factors posed by the various sources in urban areas in Kuala Lumpur.

Here, we present a case of disseminated nocardiosis, involving pneumonia, percutaneous abscess, and bacteremia, in a 67-year-old Japanese woman. She had also been treated for rheumatoid arthritis with prednisolone, methotrexate, and tocilizumab (interleukin-6 receptor inhibitor). Based on the 16S rRNA sequence analysis and a blast search, we identified the isolate as Nocardia brasiliensis. We discontinued methotrexate and tocilizumab on admission, and administered intravenous antimicrobial combination therapy for 6 weeks, followed by oral trimethoprim-sulfamethoxazole for 12 months, in total. Nocardia bacteremia is rare, often difficult to diagnose, and substantially fatal. However, due to our prompt diagnosis within one day of the onset of symptoms, and administration of appropriate treatment based on antimicrobial susceptibilities, this patient succeeded in surviving the infection. Not only microbiologists but also clinicians should be aware of the characteristic bacterial form of Gram/Kinyoun staining for early recognition of nocardiosis.

A case study was carried out to characterize the ambient PM_(2.5) based on ground-based sampling in Bangi, Selangor, Malaysia in September, 2013 during the southwest monsoon season. We determined the total mass concentration, organic carbon, elemental carbon (EC), and metals in PM_(2.5) samples. The mean PM_(2.5) mass concentration was 44.5 μg m^(-3), showing that it exceeded the national air quality standard of 35 μg m^(-3) for 24-hour PM_(2.5) by the U.S. Environmental Protection Agency. Relatively high OC and EC concentrations of this study compared to those of other Southeast Asian countries were observed, which indicate that significant sources of OC and EC exist. The results of char-EC/soot-EC ratios strongly suggest that biomass burning is the main contributor to ambient EC concentrations compared to coal combustion and motor vehicle emissions. From calculations using the mass closure model, organic matter was the most abundant component in PM_(2.5) mass at 22.4 ± 6.65 μg m^(-3), followed by nss-sulfate at 4.84 ± 2.49 μg m^(-3), and EC at 4.11 ± 0.916 μg m^(-3). This result indicates that targeting the sources of carbonaceous PM_(2.5) is a crucial step to improve the air quality in this study field.

We characterized ambient total suspended particulates (TSP) based on ground-based samplings in Malaysia during non-haze days and haze ones affected by Indonesian peatland fires. Furthermore, a key indicator of Indonesian peatland fire was determined based on chemical characterization of TSP in Malaysia. TSP samples were chemically analyzed to determine organic carbon (OC), elemental carbon (EC), inorganic ions, and biomarkers (solvent-extractable organic compounds derived from biomass burning). Regarding OC and EC, concentrations of OC1 and OP (pyrolyzed OC) defined by IMPROVE_A protocol increased remarkably during the haze episodes. On the contrary, there were no significant differences in concentrations of OC4, EC, and EC fractions between the haze and non-haze samples. Regarding inorganic ions, sulfate and ammonium concentrations increased in strong haze days, however, it is difficult to use these compounds as indicators for Indonesian peatland fires in light haze days due to the partial overlapping of the variation ranges of sulfate and ammonium concentrations in non-haze days. Concentrations of many biomarkers derived from cellulose, hemicellulose, and lignin pyrolysis products were significantly increased during strong haze days but not during light haze days except p-hydroxybenzoic acid. We proposed the OP to OC4 ratio as a potential indicator of transboundary haze pollution from Indonesian peatland fires at the receptor sites even in light haze.

In this study, we quantified carbonaceous PM2.5 in Malaysia through annual observations of PM2.5, focusing on organic compounds derived from biomass burning. We determined organic carbon (OC), elemental carbon and concentrations of solvent-extractable organic compounds (biomarkers derived from biomass burning sources and n-alkanes). We observed seasonal variations in the concentrations of pyrolyzed OC (OP), levoglucosan (LG), mannosan (MN), galactosan, syringaldehyde, vanillic acid (VA) and cholesterol. The average concentrations of OP, LG, MN, galactosan, VA and cholesterol were higher during the southwestern monsoon season (June–September) than during the northeastern monsoon season (December–March), and these differences were statistically significant. Conversely, the syringaldehyde concentration during the southwestern monsoon season was lower. The PM2.5 OP / OC4 mass ratio allowed distinguishing the seven samples, which have been affected by the Indonesian peatland fires (IPFs). In addition, we observed significant differences in the concentrations between the Indonesian peatland fire (IPF) and other samples of many chemical species. Thus, the chemical characteristics of PM2.5 in Malaysia appeared to be significantly influenced by IPFs during the southwestern monsoon season. Furthermore, we evaluated two indicators, the vanillic acid / syringic acid (VA / SA) and LG / MN mass ratios, which have been suggested as indicators of IPFs. The LG / MN mass ratio ranged from 14 to 22 in the IPF samples and from 11 to 31 in the other samples. Thus, the respective variation ranges partially overlapped. Consequently, this ratio did not satisfactorily reflect the effects of IPFs in Malaysia. In contrast, the VA / SA mass ratio may serve as a good indicator, since it significantly differed between the IPF and other samples. However, the OP / OC4 mass ratio provided more remarkable differences than the VA / SA mass ratio, offering an even better indicator. Finally, we extracted biomass burning emissions' sources such as IPF, softwood/hardwood burning and meat cooking through varimax-rotated principal component analysis.

Smoke emitted from Indonesian peatland fires has caused dense haze and serious air pollution in Southeast Asia such as visibility impairment and adverse health impacts. To mitigate the Indonesian peatland fire aerosol impacts, an effective strategy and international framework based on the latest scientific knowledge needs to be established. Although several attempts have been made, limited data exist regarding the chemical characteristics of peatland fire smoke for the source apportionment. In order to identify the key organic compounds of peatland fire aerosols, we conducted intensive field studies based on ground-based and source-dominated sampling of PM 2.5 in Riau Province, Sumatra, Indonesia, during the peatland fire seasons in 2012. Levoglucosan was the most abundant compound among the quantified organic compounds at 8.98 ± 2.28% of the PM 2.5 mass, followed by palmitic acid at 0.782 ± 0.163% and mannosan at 0.607 ± 0.0861%. Potassium ion was not appropriate for an indicator of Indonesian peatland fires due to extremely low concentrations associated with smoldering fire at low temperatures. The vanillic/syringic acids ratio was 1.06 ± 0.155 in this study and this may be a useful signature profile for peatland fire emissions. Particulate n -alkanes also have potential for markers to identify impact of Indonesian peatland fire source at a receptor site.

Biomass burning is a significant source of fine particulate matter (PM2.5). Forest, bush, and peat fires in Kalimantan and Sumatra, Indonesia are major sources of transboundary haze pollution in Southeast Asia. However, limited data exist regarding the chemical characteristics of aerosols at sources. We conducted intensive field studies in Riau Province, Sumatra, Indonesia, during the peatland fire and non-burning seasons in 2012. We characterized PM2.5 carbonaceous aerosols emitted from peatland fire based on ground-based source-dominated sampling. PM2.5 aerosols were collected with two mini-volume samplers using Teflon and quartz fiber filters. Background aerosols were also sampled during the transition period between the non-burning and fire seasons. We analyzed the carbonaceous content (organic carbon (OC) and elemental carbon (EC)) by a thermal optical reflectance utilizing the IMPROVE_A protocol and the major organic components of the aerosols by a gas chromatography/mass spectrometry. PM2.5 aerosols emitted from peatland fire were observed in high concentrations of 7120 ± 3620 μg m−3 and were primarily composed of OC (71.0 ± 5.11% of PM2.5 mass). Levoglucosan exhibited the highest total ion current and was present at concentrations of 464 ± 183 μg m−3. The OC/EC ratios (36.4 ± 9.08), abundances of eight thermally-derived carbon fractions, OC/Levoglucosan ratios (10.6 ± 1.96), and Levoglucosan/Mannosan ratios (10.6 ± 2.03) represent a signature profile that is inherent in peatland fire. These data will be useful in identifying contributions from single or multiple species in atmospheric aerosol samples collected from peatland fires.

Nitrogen dioxide and nitrous acid (HONO) in the atmosphere were simultaneously measured with a filter pack (FP) method in Ho Chi Minh City, Vietnam (HCM), in 2017 and 2018. To collect NO2 effectively, the absorption performance of NO2 by the FP method with a triethanolamine (TEA)-impregnated filter was improved. After HNO3 and HONO in the sample air were collected by NaCl and Na2CO3 impregnated filters, respectively, at 2.0 or 4.0 dm3 min−1, NO2 was collected. The air flow was divided into two lines after the HNO3 and HONO filter pack, and one line was used for collecting NO2. With a 0.1 dm3 min−1 flow rate and 20 wt% TEA in the impregnating solution, the collection efficiency of NO2 was almost 100%. The present method was applied for the measurement of HONO and NO2 in HCM in August 2017 and 2018. The average concentrations (29–48 h average) of NO2 and HONO were 17.1 ± 5.7 ppb (average ± 1 standard deviation) and 2.2 ± 0.6 ppb, respectively. The average HONO/NO2 ratio of 13.4 ± 3.5% was significantly higher by a considerable margin than reported values in the literature.

Second-generation total synthesis of aplyronine A, a potent antitumor marine macrolide, was achieved using Ni/Cr-mediated coupling reactions as key steps. The overall yield of the second-generation synthetic pathway of aplyronine A was 1.4%, obtained in 38 steps based on the longest linear sequence. Compared to our first-generation synthetic pathway of aplyronine A, the second-generation synthesis greatly improved both the yield and number of steps. In particular, we improved the stereoselectivity in the construction of the C13 stereogenic center and the C14–C15 (E)-trisubstituted double bond using the asymmetric Ni/Cr-mediated coupling reaction. Furthermore, we established efficient reaction conditions for the asymmetric Ni/Cr-mediated coupling reaction between the C21–C28 segment and C29–C34 segment. Thus, this coupling reaction proceeded with an equimolar ratio of each segment.

In this report the new black-glass fiber-preform fabricated by the vapor-phase axial deposition (VAD) method to realize high-resolution optical bundle fibers is discussed with the Energy Dispersive X-ray (EDX) analysis and the transmittance spectrum measurement. The black glass consists of SiO2, GeO2, Bi2O3 and Al2O3. Firstly, the rod-shaped soot of SiO2 and GeO2 is prepared by blowing SiCl4 and GeCl4 into the oxyhydrogen burner. Then the soot is dipped into the solution of the Bi and Al compounds. After drying the soot with Bi and Al penetrated, the soot is consolidated into the glass preform by heating with the carbon heater at 1650 degrees Celsius. The diameter of the obtained preform is 10.5 mm and the black glass layer thickness is 2.6 mm located at the periphery. The Bi concentration distribution shows the content of several wt% in the black glass layer. The black glass preform is drawn into the black optical fiber being expected to make a clear image because of no light leaking from the neighboring optical fibers as compared to the conventional fiber endoscope.

Hydrogen sulfide (H2S) is a highly toxic gaseous molecule that causes death to humans exposed to high concentrations. H2S is absorbed into the body through the alveolar epithelium and other tissues. The aim of this study is to evaluate the molecular mechanism underling acute lung injury caused by the inhalation of high concentrations of H2S. Rat lung epithelium-derived L2 cells were exposed to a H2S donor, NaHS, at concentrations of 2-4 mM for 1-6 hr. NaHS caused shrinkage and death of the cells without caspase activation. An actin-binding protein, transgelin, was identified as one of the NaHS-inducible proteins in the cells. NaHS increased myosin light chain (MLC) phosphorylation, indicating that actomyosin-mediated cellular contractility and/or motility could be increased after NaHS exposure. The administration of ML-7, a myosin light chain kinase (MLCK) inhibitor, accelerated cell death after NaHS exposure. Based on these data, we conclude that the increase in MLC phosphorylation in response to NaHS exposure is a cellular protective reaction against NaHS toxicity. Enhancements in smooth muscle cell properties such as transgelin expression and actomyosin-mediated contractility/motility might be involved in cell survival after NaHS exposure.

Chloroplasts change their intracellular distribution in response to light intensity. CHUP1 (CHLOROPLAST UNUSUAL POSITIONING1) is indispensable for this response in Arabidopsis thaliana. However, involvement of CHUP1 in light-induced chloroplast movement is unknown in other plants. In this study, CHUP1 orthologues were isolated from a moss, Physcomitrella patens, and a fern, Adiantum capillus-veneris, by cDNA library screening and PCR cloning based on the P. patens genome sequence. Functional motifs found in CHUP1 of A. thaliana were conserved among the CHUP1 orthologues. In addition to the putative functional regions, the C-terminal regions (approximately 250 amino acids), which are unique in CHUP1s, were highly conserved. Green fluorescent protein (GFP) fusions of P. patens CHUP1s (PpCHUP1A, PpCHUP1B and PpCHUP1C) were transiently expressed in protoplast cells. All GFP fusions were localized on the chloroplasts. Light-induced chloroplast avoidance movement of chup1 disruptants of P. patens was examined in the presence of cytoskeletal inhibitors because of the utilization of both microtubules and actin filaments for the movement in P. patens. When actin filaments were disrupted by cytochalasin B, the wild type (WT) and all chup1 disruptants showed chloroplast avoidance movement. However, when microtubules were disrupted by Oryzalin, chloroplasts in ∆chup1A and ∆chup1A/B rarely moved and stayed in the strong light-irradiated area. On the other hand, WT, ∆chup1B and ∆chup1C showed chloroplast avoidance movement. These results suggest that PpCHUP1A predominantly mediates the actin-based light-induced chloroplast avoidance movement. This study reveals that CHUP1 functions on the chloroplasts and is involved in the actin-based light-induced chloroplast avoidance movement in P. patens.

In this study, we used the general dynamic equation (GDE) for aerosols, combined with particle charging by positive ions and electrons, to simulate particle generation in laser ablation plasmas. The population balance equations based on Brownian coagulation and diffusion charging theory were represented by using a discrete-sectional model. The temporal evolution of the particle size distribution was simulated at three different initial number concentrations of neutral monomers, positive ions and electrons, as well as at two different gas pressures. The simulated average particle size increased with time and with increasing initial concentration of neutral monomer and gas pressure. The particle growth was affected by the particle charging when both number ratios of positive ion to neutral monomer and of electron to neutral monomer are higher than 0.1. Simulated particle size distributions were compared with SEM images of particles collected at different sampling points and gas pressures in actual plasmas operating at conditions similar to those simulated. Changes of particle size with increasing distance between the target and the sampling point and with increasing the pressure were well reproduced by simulations. However, particle diameters calculated were much smaller than SEM images because physical values, such as, initial concentrations of monomer, positive ions and electrons and the recombination probability of electron and positive ions, used in calculations were invalid.

We report the spectral behavior and averaged output power of a supercontinuum beam generated with an ytterbium (Yb)-doped double-clad passive fiber as a gain media for an amplifier with a mode-locked oscillator at a repetition rate of 10 MHz. The flat spectra was observed with a wavelength and average power of 6.2 W in the near-infrared spectral range of 1–2.3 μm, which represents a bandwidth of 1.1 μm at the 20-m-long Yb-doped double-clad passive fiber.

We describe the production of mid-infrared (mid-IR) short carbon dioxide (CO2) laser pulses with variable durations from 3 to 15ns at a maximum pulse energy of 150 mJ/pulse using a germanium (Ge) substrate semiconductor switch and a multipass amplifier. The results clearly show the spectral profiles possess all of the desired characteristics as well as the possibility of obtaining an energy conversion efficiency close to the theoretical upper limit. It is also shown that it is necessary to irradiate with pulse durations less than 10ns to optimize efficient EUV emission using Sn and Gd targets.

We separated and analyzed several organic and inorganic phases of the carbonaceous chondrite matrix to determine whether they contained any inherent asymmetry. Our intent was to determine any possible foci of asymmetry besides the one determined for meteoritic amino acids. As a probe, we employed a very sensitive asymmetric autocatalytic reaction. We were able to determine that asymmetry still resides in powders after extraction with water and solvents as well as in the insoluble organic material (IOM) obtained after demineralization. Asymmetry is not found any longer in the IOM after hydrothermal treatment and in meteorite powders from which all organics had been removed by O2 plasma at low temperature. The data are interpreted to indicate a diverse molecular asymmetry residing in yet unknown meteorite organics; these organics might have had an inductive effect on organic molecular evolution upon exogenous delivery to the early Earth.

Changes of the fluorescence spectra of tetrakis(4-sulfonatophenyl)porphyrin (TPPS) and tetrakis(4-carboxyphenyl)porphyrin (TCPP) chemisorbed on TiO2 film in pH-adjusted water have been investigated...

Circular dichroism (CD) signals of J-aggregates of 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin (TPPS4) fixed on mesoporous TiO2 film were induced by adsorption of D-tartaric acid. The intensity...

Macroporous monoliths of SiO2–Al2O3 cryogels were prepared. Macropores were generated by using ice crystals as the template, while the walls which surround the macropores were tailored as porous cryogels by freeze drying. Macropores and walls formed honeycomb-like structures, which were confirmed from scanning electron microscopy images of cross-sections of the samples. It was confirmed that the sizes of the macropores and the wall thicknesses were respectively in the ranges of 10–20 µm and 200–500 nm. Al mapping analysis by energy dispersive X-ray diffractometry showed that Al atoms were homogeneously dispersed throughout the samples without local aggregation. Moreover, Raman spectroscopy and 27Al NMR spectroscopy indicated that Al atoms were incorporated into the silica framework by forming an Al–O–Si polymeric network. Nitrogen adsorption–desorption measurements indicated that the walls were micro/mesoporous with high BET surface areas (>700 m2 g−1) and large pore volumes (>0.45 cm3 g−1). Moreover, NH3-TPD measurements revealed that the samples had acid sites, which allowed this material to be used as a solid acid catalyst.

The effect of extracellular ATP on adipogenesis was investigated using the mouse 3T3-L1 cell line. Incubation of cells with ATP (1–100 μM) for 5 min induced actin filament reorganization and membrane ruffling mediated through P2Y receptors. Enhancement of preadipocyte migration into fat cell clusters is one of the essential processes of adipose tissue development in vivo and cell migration assays revealed that stimulation of P2Y receptors enhanced chemokinesis (migration) in a concentration dependent manner. In this cell line, growth arrest is required before initiation of differentiation and growth-arrested post-confluent cells can be converted into adipocytes by the presence of the adipogenic hormones dexamethasone, 3-isobutyl-1-methylxanthine and insulin. On the other hand, those hormones alone do not trigger differentiation in proliferating cells. ATP did not induce differentiation when applied alone to either proliferating or postconfluent cells. By contrast, proliferating cells (density

The human ether-a-go-go-related gene (HERG) potassium current (IHERG) has been shown to decrease in amplitude following stimulation with Gq protein-coupled receptors (GqRs), such as α1-adrenergic and M1-muscarinic receptors (α1R and M1R, respectively), at least partly via the reduction of membrane phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2). The present study was designed to investigate the modulation of HERG channels by PI(4,5)P2 and phosphatidylinositol4-phosphate 5-kinase (PI(4)P5-K), a synthetic enzyme of PI(4,5)P2. Whole-cell patch-clamp recordings were used to examine the activity of HERG channels expressed heterologously in Chinese Hamster Ovary cells. The stimulation of α1R with phenylephrine or M1R with acetylcholine decreased the amplitude of IHERG accompanied by a significant acceleration of deactivation kinetics and the effects on IHERG were significantly attenuated in cells expressing PI(4)P5-K. The density of IHERG in cells expressing GqRs alone was significantly increased by the coexpression of PI(4)P5-K without significant differences in the voltage dependence of activation and deactivation kinetics. The kinase-deficient substitution mutant, PI(4)P5-K-K138A did not have these counteracting effects on the change in IHERG by M1R stimulation. These results suggest that the current density of IHERG is closely dependent on the membrane PI(4,5)P2 level, which is regulated by PI(4)P5-K and GqRs and that replenishing PI(4,5)P2 by PI(4)P5-K recovers IHERG.

A hybrid compound consisting of aplyronine A and mycalolide B was synthesized, and its biological activities were evaluated. The hybrid compound was found to have somewhat more potent actin-depolymerizing activity than aplyronine A. In contrast, the hybrid compound possessed about 1000-fold less cytotoxicity than aplyronine A. These results indicated that there is no direct correlation between actin-depolymerizing activity and cytotoxicity.

An efficient synthesis of the C1−C19 segment of aplyronine A is described. Stereoselective construction of the C14−C15 (E)-trisubstituted double bond and the C13 stereocenter was achieved by using an asymmetric Nozaki−Hiyama−Kishi coupling.

We demonstrated the generation of the intense radially polarized mid-infrared optical vortex at a wavelength of 10.6 μm by use of a passive axially symmetric zinc selenide (ZnSe) waveplate with high energy pulse throughput. The phase of the radially polarized optical vortex with the degree of polarization of 0.95 was spirally distributed in regard to the angle. The converted laser beam energy of about 2.6 mJ per pulse was obtained at the input pulse energy of 4.9 mJ, corresponding to the energy conversion efficiency of 56%.

Protonated TPPS4 monomer and its J-aggregate were formed simultaneously from TPPS4 adsorbed through its sulfonic acid groups on TiO2 porous film by decreasing the pH of the surrounding water and this behavior on TiO2 film can be reversibly repeated depending on pH, indicating a flexible and stable arrangement of TPPS4 through chemical bonds between the sulfonic acid groups and the TiO2 surface.

HP-β-CD–porphyrin inclusion complexes were formed on TiO2 film by use of water-soluble porphyrin such as TCPP and TPPS, respectively. Quite intense fluorescence spectra of porphyrins were recovered...