As the skin is the largest body organ and critically serves as a barrier, it is frequently exposed and could be physiologically affected by radiofrequency electromagnetic field (RF-EMF) exposure. In ...this study, we found that 1760 MHz RF-EMF (4.0 W/kg specific absorption rate for 2 h/day during 4 days) exposure could induce intracellular reactive oxygen species (ROS) production in HaCaT human keratinocytes using 2',7'-dichlorofluorescin diacetate fluorescent probe analysis. However, cell growth and viability were unaffected by RF-EMF exposure. Since oxidative stress in the skin greatly influences the skin-aging process, we analyzed the skin senescence-related factors activated by ROS generation. Matrix metalloproteinases 1, 3, and 7 (MMP1, MMP3, and MMP7), the main skin wrinkle-related proteins, were significantly increased in HaCaT cells after RF-EMF exposure. Additionally, the gelatinolytic activities of secreted MMP2 and MMP9 were also increased by RF-EMF exposure. FoxO3a (Ser318/321) and ERK1/2 (Thr 202/Tyr 204) phosphorylation levels were significantly increased by RF-EMF exposure. However, Bcl2 and Bax expression levels were not significantly changed, indicating that the apoptotic pathway was not activated in keratinocytes following RF-EMF exposure. In summary, our findings show that exposure to 1760 MHz RF-EMF induces ROS generation, leading to MMP activation and FoxO3a and ERK1/2 phosphorylation. These data suggest that RF-EMF exposure induces cellular senescence of skin cells through ROS induction in HaCaT human keratinocytes.
Environmentally adapted and resistant hard and soft coral communities within the high-latitude Asia–Pacific marginal distribution zone are thriving, despite their comparably stressful environment ...(unfavorable winter water temperature and light regimes). Korea’s Jeju Island is famous for its diverse and abundant soft coral communities, which coexist with reef-building hard corals. Although antagonistic interactions between soft and hard corals generally feature the soft coral as the winner, we observed a soft coral of the species Dendronephthya gigantea completely enclosed by the encrusting hard coral Montipora millepora accompanied by a general decrease in soft coral and increase in M. millepora abundances. This indicates an ongoing species/habitat shift with significant impacts on the current state of corals living at their geographic limit.
In the present study, we fabricated composite polyvinyl alcohol (PVA) and pectin hydrogels with different blend ratios using a freeze–thaw method. Scanning electron microscopy revealed that the ...PVA/pectin hydrogels had a porous structure, with the porosity increasing from 82.8% ± 0.5% to 93.2% ± 0.3% with an increase in the pectin content. In addition, with the addition of pectin, the gel fraction of the hydrogel decreased and the swelling ability increased compared with PVA. Of the fabricated hydrogels, the hydrogel with the 9:1 PVA/pectin ratio had the highest compressive strength (684 ± 62 kPa) and G′ value (~1014 kPa). Based on cytotoxicity studies, none of the fabricated hydrogels showed cytotoxicity against HDF or HaCaT cells. These results indicate that varying the pectin content can be used to control the mechanical characterization, porosity, and swelling ability of composite PVA/pectin hydrogels, which are thus promising candidates for use as wound dressings.
Prolongation of the picosecond Raman pump laser pulse in the femtosecond stimulated Raman spectroscopy (FSRS) setup is essential for achieving the high spectral resolution of the time-resolved ...vibrational Raman spectra. In this work, the 2nd-order diffraction has been firstly employed in the double-pass grating filter technique for realizing the FSRS setup with the sub-5 cm
spectral resolution. It has been experimentally demonstrated that our new FSRS setup gives rise to a highly-resolved Raman spectrum of the excited trans-stilbene, which is much improved from those reported in the literatures. The spectral resolution of the present FSRS system has been estimated to be the lowest value ever reported to date, giving Δν = 2.5 cm
.
Coffee waste is an abundant biomass that can be converted into high value chemical products, and is used in various renewable biological processes. In this study, oil was extracted from spent coffee ...grounds (SCGs) and used for polyhydroxyalkanoate (PHA) production through
. The oil-extracted SCGs (OESCGs) were hydrolyzed and used for biohydrogen production through
DSM10702. The oil extraction yield through
-hexane was 14.4%, which accounted for 97% of the oil present in the SCGs. OESCG hydrolysate (OESCGH) had a sugar concentration of 32.26 g/L, which was 15.4% higher than that of the SCG hydrolysate (SCGH) (27.96 g/L). Hydrogen production using these substrates was 181.19 mL and 136.58 mL in OESCGH and SCGH media, respectively. The consumed sugar concentration was 6.77 g/L in OESCGH and 5.09 g/L in SCGH media. VFA production with OESCGH (3.58 g/L) increased by 40.9% compared with SCGH (2.54 g/L). In addition, in a fed-batch culture using the extracted oil, cell dry weight was 5.4 g/L, PHA was 1.6 g/L, and PHA contents were 29.5% at 24 h.
In this study, potential anti-inflammatory effect of fucoxanthin isolated from brown algae was assessed via inhibitory effect of nitric oxide (NO) production in lipopolysaccharide (LPS) induced RAW ...264.7 macrophage cells. The
Myagropsis myagroides was selected for further experiments due to its profound NO inhibitory effect, and was partitioned with different organic solvents. Highest NO inhibitory effect was detected in the chloroform fraction, and the active compound was identified as fucoxanthin, a kind of carotenoid available in brown algae evidenced high correlation with the inhibitory effect of NO production (
r
2
=
0.9511). Though, fucoxanthin significantly inhibited the NO production, it slightly reduced the prostaglandin E
2 (PGE
2) production. The inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) protein expressions were inhibited by fucoxanthin. Further, RT-PCR analysis indicated that the iNOS and COX-2 mRNA expressions were suppressed by fucoxanthin. Moreover, the release of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6), and the mRNA expression levels of those cytokines were reduced by the addition of fucoxanthin in a dose-dependent manner. Hence, these results suggest that the use of fucoxanthin may be a useful therapeutic approach for the various inflammatory diseases.
Alginate and pectin have been widely employed together in various industrial and biomedical applications due to their synergistic interaction. Although alginate and pectin have been used as composite ...materials in films, gels, and particles, research characterizing their properties in foams is scarce. Thus, in the present study, we fabricated alginate-pectin composite foams with different blending ratios (9:1, 7:3, and 5:5) using calcium ion cross-linking and characterized their properties. It was found that the G′ values of rehydrated alginate-pectin 9:1 foam was higher than those of the other rehydrated foams in the rheological behavior. In addition, higher pectin levels in the composite foams led to more water being absorbed during swelling tests and the higher release of BSA in drug-release testing. In indirect and direct cytotoxicity testing, none of the foams exhibited cell cytotoxicity for fibroblast and keratinocyte cells. These results suggest that controlling the pectin content in alginate-pectin foams is key to adjusting their mechanical properties, water absorption, and drug-release ability. In addition, alginate-pectin composite foams are promising candidates for use in wound-dressing applications.
We recently identified a β-agarase, Gaa16B, in the marine bacterium
JEA5. Gaa16B, belonging to the glycoside hydrolase 16 family of β-agarases, shows less than 70.9% amino acid similarity with ...previously characterized agarases. Recombinant Gaa16B lacking the carbohydrate-binding region (rGaa16Bc) was overexpressed in
and purified. Activity assays revealed the optimal temperature and pH of rGaa16Bc to be 55 ∘C and pH 6-7, respectively, and the protein was highly stable at 55 ∘C for 90 min. Additionally, rGaa16Bc activity was strongly enhanced (2.3-fold) in the presence of 2.5 mM MnCl
. The
and
of rGaa16Bc for agarose were 6.4 mg/mL and 953 U/mg, respectively. Thin-layer chromatography analysis revealed that rGaa16Bc can hydrolyze agarose into neoagarotetraose and neoagarobiose. Partial hydrolysis products (PHPs) of rGaa16Bc had an average molecular weight of 88-102 kDa and exhibited > 60% hyaluronidase inhibition activity at a concentration of 1 mg/mL, whereas the completely hydrolyzed product (CHP) showed no hyaluronidase at the same concentration. The biochemical properties of Gaa16B suggest that it could be useful for producing functional neoagaro-oligosaccharides. Additionally, the PHP of rGaa16Bc may be useful in promoting its utilization, which is limited due to the gel strength of agar.
Real-time autodetachment dynamics of the loosely bound excess electron from the vibrational Feshbach resonances of the dipole-bound states (DBS) of 4-bromophonoxide (4-BrPhO
−
) and 4-chlorophenoxide ...(4-ClPhO
−
) anions have been thoroughly investigated. The state-specific autodetachment rate measurements obtained by the picosecond time-resolved pump-probe method on the cryogenically cooled anions exhibit an exceptionally long lifetime (
τ
) of ∼823 ± 156 ps for the 11′
1
vibrational mode of the 4-BrPhO
−
DBS. Strong mode-dependency in the wide dynamic range has also been found, giving
τ
∼ 5.3 ps for the 10′
1
mode, for instance. Though it is nontrivial to get the state-specific rates for the 4-ClPhO
−
DBS, the average autodetachment lifetime of the 19′
1
20′
1
/11′
1
mode has been estimated to be ∼548 ± 108 ps. Observation of these exceptionally slow autodetachment rates of vibrational Feshbach resonances strongly indicates that the correlation effect may play a significant role in the DBS photodetachment dynamics. Fermi's golden rule has been invoked so that the correlation effect is taken into account in the form of the interaction between the charge and the induced dipole where the latter is given by the polarizable counterparts of the electron-rich halogenated compound and the diffuse non-valence electron. This report suggests that one may measure, from the real-time autodetachment dynamics, the extent of the correlation effect contribution to the stabilization and/or dynamics of the excess non-valence electron among many different types of long-range interactions of the DBS.
Exceptionally slow autodetachment dynamics of the vibrational Feshbach resonances found in the dipole-bound state of 4-bromophonoxide (4-BrPhO
−
) or 4-chlorophenoxide (4-ClPhO
−
) anions reveals the associated dynamic role of the correlation effect.
The ponderomotive force on molecular systems has rarely been observed hitherto, despite potentially being extremely useful for the manipulation of the molecular properties. Here, the ponderomotive ...effect in the non-valence bound states has been experimentally demonstrated, for the first time to the best of our knowledge, giving great promise for the manipulation of polyatomic molecules by the dynamic Stark effect. Entire quantum levels of the dipole-bound state (DBS) and quadrupole-bound state (QBS) of the phenoxide (or 4-bromophenoxide) and 4-cyanophenoxide anions, respectively, show clear-cut ponderomotive blue-shifts in the presence of the spatiotemporally overlapped non-resonant picosecond control laser pulse. The quasi-free electron in the QBS is found to be more vulnerable to the external oscillating electromagnetic field compared to that in the DBS, suggesting that the non-valence orbital of the former is more diffusive and thus more polarizable compared to that of the latter.
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