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The fluorescence quenching strategy has been developed as an exceedingly selective and sensitive method for the determination of Cu2+ ions in the presence of CO32− ions in an aqueous medium.

The purpose of this study was to identify the ideal storage period for frozen minced beef products and to under-stand key factors affecting their quality. Frozen minced beef products with 10 and 15% of fat content were kept at ?5, ?15, and ?23°C, and over a 6-month period, they were assessed for moisture content (MC), peroxide values (POV), acid values (AV), 2-thiobarbituric acid (TBA) value, total volatile basic nitrogen content (TVB-N), and the sensory test in order to identify the effect on quality. This helped to determine their appropriate storage duration at a given temperature. Multiple regression analysis was used to assess the correlations between storage tempera-ture, fat meat percentage, characteristic factors, and overall acceptance (OA). Five months for ?23°C, 4 months for ?15°C, and 2 months for ?5°C met 3.7 points or more of OA, in accordance with global sensory analysis stan-dards, and were determined as acceptable frozen storage durations. The very high multiple regression analysis R2 (0.97–0.99) verified the correlation between the characteristic factors and OA. In addition, TVB-N, MC, and POV, respectively, were the main quality factors affecting OA at ?5, ?15, and ?23°C (R2 > 0.8). These findings may prove useful and practical for manufacturers to improve storage and distribution practices in maintaining the quality of frozen minced beef products.

Non-small cell lung cancer (NSCLC) is the leading cause of lung cancer-related deaths worldwide. Tumor-associated macrophages (TAMs), which can be polarized into tumor-promoting M2 phenotype, overexpress folate receptor beta (FRβ) and are associated with poor prognosis in NSCLC. In addition, calpain-2 (CAPN2) is overexpressed in NSCLC and is involved in tumor growth. To improve the anticancer efficacy of drugs and reduce their side effects in the treatment of NSCLC, it is important to develop smart drug delivery systems with specific targeting ability and controlled release mechanisms. In this study, FRβ-targeted pH-sensitive liposomes were designed as carriers to ensure efficient drug delivery and acid-responsive release in NSCLC cells. Folate-mediated targeting of FRβ in M2 TAMs and NSCLC cells effectively inhibited tumor growth and the stimulus-responsive drug release reduced the toxic side effects of the drug. The combination of doxycycline (anti-CAPN2) and docetaxel (anticancer drug) showed a synergistic inhibitory effect on tumor growth by suppressing CAPN2 expression.

Complex structure of cyanobacterium Nostoc sp. exopolysaccharide (EPS), with apparent molecular weight 214 × 103 g/mol, can be deduced from its composition. Chemical and NMR analyses found four dominant sugar monomers, namely (1 → 4)-linked α- l -arabinopyranose, β- d -glucopyranose, β- d -xylopyranose and (1 → 3)-linked β- d -mannopyranose, two different uronic acids and a lactyl group, with (1 → 4,6)-linked β- d -glucopyranose as the only branch point suggest a complex structure of this polymer. The dominant uronic acid is α-linked, but it remained unidentified. β- d -Glucuronic acid was present in lower amount. Their position as well as that of lactyl remained undetermined too. Different doses of orally administered EPS in guinea pigs evoked a significant decrease in cough effort and a decrease in airway reactivity. The antitussive efficacy and bronchodilator effect of higher doses of EPS were found to be similar to that of the antitussive drug codeine and the antiasthmatic salbutamol. Without significant cytotoxicity on the RAW 264.7 cells, EPS stimulated the macrophage cells to produce pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), and prostaglandins (PGs) and nitric oxide (NO) via induction of COX-2 and iNOS expression, respectively, suggesting that this biopolymer potentiates an early innate immune response and can therefore be used as a new immune modulator.

The self-organization of colloidal nanoparticles into programmed suprastructures is an important research area in various disciplines of nano, colloid, and polymer sciences. However, despite the re...

Recently, the production of exopolysaccharide from Pseudozyma sp. SY16, which is mannosylerythritol lipid-producing yeast, has been occasionally observed during industrial fermentations. Moreover, exopolysaccharides derived from microbes are in high demand for the production of biopolymers. Therefore, this study aimed to investigate the production and characteristics of the exopolysaccharide produced by this strain. In batch fermentations with this strain, the maximum production yield of exopolysaccharide (5.8 g/L) was obtained under olive oil supplementation as a carbon source with culture conditions of 30°C, pH 8.0, and 600 rpm. Through a series of liquid chromatography steps, the exopolysaccharide was successfully purified, and its emulsifying activity was demonstrated. In addition, two-dimensional nuclear magnetic resonance analysis revealed that the exopolysaccharide is a galactoglucomannan with a novel and unique structure, consisting of galactose, glucose, and mannose in the ratio of 1:5:3.

Manganese silicate nanoparticles have recently attracted great attention due to the effectiveness of T1-weighted magnetic resonance imaging (MRI) contrast agents (CAs) in the mildly acidic and high glutathione (GSH) conditions of the tumor microenvironment. Herein, ultra-small hollow manganese silicate (UHMS) nanoparticles were prepared via a facile, economical, and eco-friendly method based on a hydrothermal process using small silica nanoparticles as both the silicon source and templates. The nanoparticles showed remarkable biocompatibility and dispersion stability after modification with polyethylene glycol (PEG). Owing to their ultra-high longitudinal relaxation rate (r1) at low pH values and high GSH levels, the UHMS@PEG nanoparticles have performed an excellent pH/GSH-responsive T1-weighted MRI. Meanwhile, the nanoparticles showed insignificant cytotoxicity in vitro and in vivo. Therefore, the UHMS@PEG nanoparticles show promise as T1-MRI CAs in the tumor microenvironment and may be used to assist in clinical cancer diagnosis.

Proton exchange membrane fuel cell (PEMFC) utilizes polymer electrolyte membrane, e.g., Nafion™, which is a perfluorosulfonic acid (PFSA) membrane with many disadvantages such as expensive, low mechanical strength, low chemical stability at high temperatures. Meanwhile, graphene oxide membrane (GOM) is an excellent proton conductor at room temperature under humidified conditions. However, graphene oxide membrane fuel cells (GOMFCs) exhibit low maximum power density compared to Nafion due to fuel gas crossover, membrane degradation and loss of surface functionalities. In this study, bilayer membrane consisting of GOM and hydrogen permeable metal thin film was investigated as electrolyte membrane for hydrogen membrane fuel cell (HMFC). In this fuel cell, the graphene oxide-hydrogen membrane (GOHM) simultaneously plays two roles, an anode catalyst and an electrolyte. A hydrogen permeable metal thin film of about 40 nm was deposited by DC magnetron sputtering at a suitable pressure and deposition time on a 12 µm-thick GOM using a Pd or Ni64Zr36 target to complete the bilayer GOHM electrolyte. The fuel cell performance of the GOHMFC using with Pt-free anode was compared with the GOHMFC with conventional Pt/C electrodes and conventional PEMFC.

Obesity-induced inflammation and insulin resistance are mediated by macrophage infiltration into adipose tissue. We investigated the effects of 7,8-dihydroxyflavone (7,8-DHF), a flavone found in plants, on the inflammatory response and insulin resistance induced by the interaction between adipocytes and macrophages. Hypertrophied 3T3-L1 adipocytes were cocultured with RAW 264.7 macrophages and treated with 7,8-DHF (3.12, 12.5, and 50 μM). The inflammatory cytokines and free fatty acid (FFA) release were evaluated by assay kits, and signaling pathways were determined by immunoblotting. Coculture of adipocytes and macrophages increased inflammatory mediators, such as nitric oxide (NO), monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) and FFA secretion but suppressed the production of anti-inflammatory adiponectin. 7,8-DHF counteracted the coculture-induced changes (p < 0.001). 7,8-DHF also inhibited c-Jun N-terminal kinase (JNK) activation and blocked nuclear factor kappa B (NF-κB) nuclear translocation in the coculture system (p < 0.01). In addition, adipocytes cocultured with macrophages did not increase glucose uptake and Akt phosphorylation in response to insulin. However, 7,8-DHF treatment recovered the impaired responsiveness to insulin (p < 0.01). These findings show that 7,8-DHF alleviates inflammation and adipocyte dysfunction in the coculture of hypertrophied 3T3-L1 adipocytes and RAW 264.7 macrophages, indicating its potential as a therapeutic agent for obesity-induced insulin resistance.

We report a sensitive and versatile biosensing approach, LUCID (luminescence compact in vitro diagnostics), for quantitative molecular and cellular analyses. LUCID uses upconversion nanoparticles (UCNPs) as luminescent reporters in mutually exclusive photoexcitation and read-out sequences implemented on a smartphone. The strategy improves imaging signal-to-noise ratios, eliminating interference from excitation sources and minimizing autofluorescence, and thus enables filterless imaging. Here we developed a miniaturized detection system and optimized UCNPs for the system and biological applications. Nanoparticle luminescence lifetime was extended by controlling particle structure and composition. When tested with a range of biological targets, LUCID achieved high detection sensitivity (0.5 pM for protein and 0.1 pM for nucleic acids), differentiated bacterial samples, and allowed profiling of cells. In proof-of-concept clinical use, LUCID demonstrated effective screening of cancer cells in cervical brushing specimens, identifying patients at high risk for malignancy. These results suggest that LUCID could serve as a broadly applicable and inexpensive diagnostic platform.

Non-small-cell lung cancer (NSCLC) is the most frequent type of lung cancer with a high mortality rate. Glycosylation of phenolic compounds may increase water-solubility and pharmacological activities and reduce the toxicity of aglycones. This study aimed to evaluate and compare the anticancer effect of aloe emodin 3-O-glucoside (AE3G) and its aglycone, aloe emodin (AE), against NSCLC.A human adenocarcinoma cell line (A549) and other human non-small cell lung carcinoma cell lines (NCI-H460 cells and NCI-H1299 cells) and BALB/c nu/nu xenograft mice harbouring A549 cells were used as the NSCLC models. Inhibition of cell migration, disruption of mitochondrial membrane potential (MMP), DNA fragmentation, and expression levels of apoptotic proteins were measured by western blot, wound healing assay, JC-1 staining, or TUNEL staining. Histopathological changes in tumour tissues were observed by HE and TUNEL staining.With no significant cytotoxicity against noncancerous cells (Vero cells), AE3G (5-50 μM) significantly and more effectively inhibited the growth, attachment, migration, Bcl-2 expression, and activation of MEK/ERK and Akt signalling proteins and induced cytochrome c release and Bax expression in A549 cells than AE. AE3G also significantly decreased the growth of other NSCLC cells, NCI-H460 cells and NCI-H1299 cells. AE3G suppressed the mRNA expression of matrix metalloproteinases, MMP2 and MMP9, and augmented the collapse of the mitochondrial MMP, cleavage of caspases (caspase 9, 8, and 3) and PARP, and DNA fragmentation. Intraperitoneal injection of AE3G (13 and 26 mg/kg/day) reduced the tumour volume and weight and induced apoptotic cell death in tumour tissues of xenograft NSCLC mice.The present study demonstrated that AE3G significantly and more effectively diminished human NSCLC cell growth and migration by triggering mitochondria-dependent intrinsic apoptosis than AE, providing AE3G as a new potent candidate to prevent or treat human NSCLC.

Simultaneous detection of multiple targets with different analyte-recognition reactions in the same sample in a rapid, low-cost and reliable way has immense potential with widespread applications in food safety, medical diagnostics and environmental monitoring. Herein, we developed a lateral flow aptamer assay (LFAA) integrated smartphone-based portable device for highly sensitive and precise detection of multiple targets, using aptamers functionalized multi-colored upconversion nanoparticles as probes. The developed LFAA can provide rapid and sensitive analysis of three different kinds of targets (i.e., small molecules, ions and bacteria) without significant cross-reaction by using separate color channels. By using the competitive format, the concentration of each target can be determined from the color intensity of the corresponding colored band. With the LFAA, we have achieved detection ranges of 10–104 ppb, 0.01–50 μg/mL and 150–2000 CFU/mL and detection limits of 5 ppb, 3 ng/mL and 85 CFU/mL for mercury ions, ochratoxin A and Salmonella (as template analytes), respectively. The LFAA was further used for detection in real water samples (i.e., tap water) within 30 min. Subsequently, a smartphone-based device was used instead of a CCD camera to read the results, which could make the detection process rapid and portable. Therefore, the developed LFAA holds great potential as a sensitive, specific, convenient and stable platform for point-of-care detection of multiple targets in various fields.

7,8-Dihydroxyflavone (7,8-DHF, 7,8-dihydroxy-2-phenyl-4H-chromen-4-one) is a natural flavone found in plants and has been frequently reported to show anti-inflammatory and anti-oxidant properties. Skin aging is induced mainly by oxidative stress. In the present study, we evaluated 7,8-DHF for its potential anti-aging effects for skin using Hs68 human dermal fibroblast cells. To establish aged skin cell model, Hs68 cells were treated with tumor necrosis factor-α (TNF-α) for 18h 7,8-DHF (0-10μM) induced collagen synthesis and suppressed the expression of matrix metalloproteinase 1 (MMP 1) in a dose-dependent manner. 7,8-DHF also significantly reduced the generation of intracellular reactive oxygen species (ROS), induced the expression of anti-oxidant enzymes, such as catalase, manganese superoxide dismutase (Mn-SOD), and heme oxygenase-1 (HO-1), and scavenged DPPH free radicals. 7,8-DHF also disturbed the mitogen-activated protein kinases (MAPKs) and Akt signaling pathways that participate in the aging process. 7,8-DHF exerted potent anti-aging effects by inhibiting MMP 1 expression and inducing Type I collagen synthesis in Hs68 cells. 7,8-DHF effectively attenuated oxidative stress by up-regulating the anti-oxidant enzymes catalase, Mn-SOD, and HO-1, and reducing activation of the Akt and MAPKs signaling pathways in aged skin cells. These results suggest that 7,8-DHF can be used as a potent facultative ingredient in health-beneficial agents to prevent or treat the skin aging or inflammatory skin disorders.

Present study was aimed to investigate the potential anti-obesity effects of maysin, a major flavonoid of corn silk, in vitro and in vivo using 3T3-L1 preadipocyte cells and C57BL/6 mice. Maysin decreased the levels of intracellular lipid droplets and triglycerides (TG), and down-regulated the protein expression levels of C/EBP-β, C/EBP-α, PPAR-γ, and aP2 in 3T3-L1 preadipocyte cells, suggesting that maysin inhibits lipid accumulation and adipocyte differentiation. In addition, maysin was shown to induce the apoptotic cell death in 3T3-L1 preadipocyte cells via activation of caspase cascades and mitochondrial dysfunction, which may ultimately lead to reduction of adipose tissue mass. Furthermore, oral administration of maysin (25mg/kg body weight) decreased weight gain and epididymal fat weight in high-fat diet (HFD)-fed C57BL/6 mice. Administration of maysin also reduced serum levels of TG, total-cholesterol, LDL-cholesterol, and glucose. Taken collectively, these results suggest for the first time that the purified maysin exerts an anti-obesity effect in vitro and in vivo. These observations may support the applicability of maysin as a potent functional ingredient in health-beneficial foods or as a therapeutic agent to prevent or treat obesity.

We report a sensitive and versatile biosensing approach, LUCID (luminescence compact in-vitro diagnostics), for quantitative molecular and cellular analyses. LUCID uses upconversion nanoparticles (UCNPs) as luminescent reporters in mutually exclusive photo-excitation and read-out sequences implemented on a smartphone. The strategy improves imaging signal-to-noise ratios, eliminating interference from excitation sources and minimizing autofluorescence, and thus enables filter-less imaging. Here we developed a miniaturized detection system and optimized UCNPs for the system and biological applications. Nanoparticle luminescence lifetime was extended by controlling particles’ structure and composition. When tested with a range of biological targets, LUCID achieved high detect sensitivity (0.5 pM for protein and 0.1 pM for nucleic acids), differentiated bacterial samples, and allowed profiling of cells. In proof-of-concept clinical use, LUICD demonstrated effective screening of cancer cells in cervical brushing specimens, identifying patients at high risk for malignancy. These results suggest that LUCID could serve as a broadly applicable and inexpensive diagnostic platform.

Water soluble polysaccharides (WSPs) were isolated from defatted microalgae Tetraselmis sp. KCTC 12432 BP (T.S1) and KCTC 12236 BP (T.S2), and purified by a combination of ethanol precipitation, immobilized metal affinity chromatography and size-exclusion column chromatography. Biochemical properties of WSPs obtained from the supernatant (S 1 and S 2) and purification steps (EP 1 and EP 2) have been elucidated for their potential use as a biologically active material. Oxidative effect on efficiency from the hydrolytic fenton reaction (FS 1 and FS 2) was also employed to assess the WSPs production and biological activity from T.S1 and T.S2, respectively. Antioxidant activity of the purified WSPs from EP 2 toward 1,1-diphenyl-2-picryl-hy-drazyl (DPPH), 2,2’-Azinobis (3-ethylbenzothiazoline-6-sulfonic acid) di-ammonium salt (ABTS), and ferric reducing antioxidant power (FRAP) of radical-scavenging showed significant differences depending on the monosaccharide compositions of WSPs. On the other hand, a significant specific tyrosinase inhibitory activity was observed from the WSPs purified from EP 1 (10 ¼mol/g/min) indicating the potential use as a whitening source. The outcomes of our study support the utilization of WSPs from these microalgal species as a potential source of naturally occurring whitening and antioxidants to ease oxidative stresses. According to our knowledge related to microalgal studies, until now this is the first study which demonstrates the significance between primary structure and potential biological activities of WSPs purified from the defatted microalgae Tetraselmis species.

AtUGT89C1, a glycosyltransferase from Arabidopsis thaliana, has shown interesting characteristics such as accepting diverse NDP-D/L-sugars as glycosyl donors. Genistein was used as a substrate to p...

An in vitro enzymatic glycosylation system is developed for the efficient synthesis of glucosides of 3,5-dihydroxy-N-(4-hydroxyphenyl) benzamide (resvera-A), a chemically synthesized molecule resembling resveratrol in structure. Resvera-A is a pharamacophore-based designed molecule that exhibits anti-oxidant, antibacterial, anti-inflammatory, and anticancer activities. In this study, an alternative cost-effective uridine diphosphate (UDP) recycling system was established to produce UDP-α-D-glucose through a two-step enzyme-catalyzed reaction using easily available cheap sources. This UDP-α-D-glucose biosynthesis system was combined with a glycosyltransferase (YjiC, from Bacillus licheniformis)-catalyzed reaction for the synthesis of glucoside derivatives of resvera-A. The side product of the glycosylation reaction, UDP, was used as a precursor for the biosynthesis of UDP-α-D-glucose, which is used by YjiC for glycosylation, thus recycling UDP. As a result, two novel molecules, resvera-A 3-O-α-D-glucoside (42.33 mg, 2.10 mM, 0.84 mg/mL) and resvera-A 4'-O-α-D-glucoside (99.38 mg, 4.87 mM, 1.98 mg/mL), were synthesized within 4 h from 50 mL preparative scale reaction using only 0.1 mM of UDP-α-D-glucose, 100 folds lower concentration than the concentration of resvera-A (10 mM) used. Structures of both products were elucidated using liquid chromatography, mass spectroscopy, and nuclear magnetic resonance analysis.

Emodin (Emo) is a natural plant anthraquinone derivative with a wide spectrum of pharmacological properties, including anticancer, antioxidant, and hepatoprotective activities. Glycosylation of natural anthraquinones with various sugar moieties can affect their physical, chemical, and biological functions. In this study, the potential immunomodulatory activities of Emo and its glycosylated derivative, emodin 8-O-glucoside (E8G), were evaluated and compared using murine macrophage RAW264.7 cells and human monocytic THP-1 cells. The results showed that E8G (20 μM) induced the secretion of TNF-α and IL-6 from RAW264.7 cells more effectively than unglycosylated Emo aglycone, by 4.9- and 1.6-fold, respectively, with no significant cytotoxicity in the concentration range tested (up to 20 μM). E8G (2.5–20 μM) significantly and dose-dependently induced inducible nitric oxide synthase (iNOS) expression by up to 3.2-fold compared to that of untreated control following a remarkable increase in nitric oxide (NO) production. E8G also significantly increased the expression of TLR-2 mRNA and the phosphorylation of MAPKs (JNK and p38). The activation and subsequent nuclear translocation of NF-κB was substantially enhanced upon treatment with E8G (2.5–20 μM). Moreover, E8G markedly induced macrophage-mediated phagocytosis of apoptotic Jurkat T cells. These results demonstrated that E8G far more strongly stimulates the secretion of proinflammatory cytokines, such as TNF-α and IL-6, and NO production from macrophages through upregulation of the TLR-2/MAPK/NF-κB signalling pathway than its nonglycosylated form, Emo aglycone. These results suggest for the first time that E8G may represent a novel immunomodulator, enhancing the early innate immunity.

Protein digestion, using an enzyme called trypsin (TR), is one of the key steps in proteomic analysis. The current technology of protein digestion in proteomic analysis is time-consuming, tedious and not-automated due to the poor stability and autolysis of trypsin. To improve the protein digestion process, trypsin was immobilized and stabilized on polymer nanofibers entrapping superparamagnetic nanoparticles (magnetic nanofibers, NP-NFs). By electrospinning the homogeneous mixture of superparamagnetic nanoparticles (NPs) and polystyrene-poly(styrene-co-maleic anhydride), NPs could be effectively entrapped within polymer nanofibers, generating magnetically-separable nanofibers with high surface area for trypsin immobilization via the approach of enzyme coatings. Trypsin coatings on magnetic nanofibers (EC-TR/NP-NFs; EC-TR), fabricated via simple attachment of crosslinked trypsin molecules onto NP-NFs, were highly stable and could be recycled via facile magnetic separation. EC-TR showed negligible loss of trypsin activity even after incubation in an aqueous buffer under rigorous shaking (200 rpm) for 80 days, while the control samples of covalently-attached trypsin on NP-NFs (CA-TR/NP-NFs; CA-TR) and free trypsin lost more than 90% of their initial activities within 11 and 6 days, respectively. When highly-stable and magnetically-separable EC-TR was employed for the repetitive digestions of enolase under recycled uses for the duration of 50 days and even after treatment with another protease (chymotrypsin) for 32 h, the performance of enolase digestion was successfully maintained. The use of EC-TR for the enolase digestion in the ultra-sonication system resulted in fast (∼10 min) and efficient digestions with reproducible performance under recycled uses.

Quercetin is a natural plant flavonoid that has been reported to possess a wide range of beneficial health effects, including anti-cancer and anti-inflammatory activities. Glycosylation of natural flavonoids with various sugar moieties can affect their physical, chemical, and biological properties. In this study, quercetin 3-O-xyloside (Quer-xyl) was enzymatically synthesized, and the immunomodulatory activities of quercetin and Quer-xyl were evaluated and compared. The results showed that Quer-xyl more effectively induced the secretion of TNF-α and IL-6 than quercetin by 2.5 and 1.5-fold, respectively. Quer-xyl dose-dependently induced the inducible nitric oxide synthase (iNOS) expression and increased the production of nitric oxide (NO) 1.3-fold more than quercetin. Quer-xyl also increased the phosphorylation of ASK1 and MAPKs (JNK and p38). Treatment with NQDI-1 (an inhibitor of ASK1) significantly attenuated the Quer-xyl-induced up-regulation of TNF-α secretion. The activation and subsequent nuclear translocation of NF-κB were substantially enhanced upon treatment with Quer-xyl (2.5-20 μM), while NQDI-1 treatment blocked the nuclear translocation of NF-κB. These results demonstrated that Quer-xyl can enhance the early innate immunity more effectively than quercetin by activating macrophages to secrete TNF-α and IL-6 through up-regulation of the redox-dependent ASK1/MAPK/NF-κB signaling pathway, suggesting for the first time that Quer-xyl may represent a new immunostimulator.

Rapid pathogen testing is expected to play a critical role in infection control and in limiting epidemics. Smartphones equipped with state-of-the-art computing and imaging technologies have emerged as new point-of-use (POU) sensing platforms. We herein report a new assay format for fast, sensitive and portable detection of avian influenza-associated antibodies.

Numerous studies have suggested that neuronal cells are protected against oxidative stress-induced cell damage by antioxidants, such as polyphenolic compounds. Phellinus linteus (PL) has traditionally been used to treat various symptoms in East Asian countries. In the present study, we prepared an ethyl acetate extract from the fruiting bodies of PL (PLEA) using hot water extraction, ethanol precipitation, and ethyl acetate extraction. The PLEA contained polyphenols as its major chemical component, and thus, we predicted that it may exhibit antioxidant and neuroprotective effects against oxidative stress. The results showed that the pretreatment of human brain neuroblastoma SK-N-MC cells with the PLEA (0.1-5 μ g/mL) significantly and dose-dependently reduced the cytotoxicity of H 2 O 2 and the intracellular ROS levels and enhanced the expression of HO-1 (heme oxygenase-1) and antioxidant enzymes, such as CAT (catalase), GPx-1 (glutathione peroxidase-1), and SOD-1 and -2 (superoxide dismutase-1 and -2). The PLEA also directly scavenged free radicals. PLEA pretreatment also significantly attenuated DNA fragmentation and suppressed the mRNA expression and activation of mitogen-activated protein kinases extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38 kinase, which are induced by oxidative stress and lead to cell death. PLEA pretreatment inhibited the activation of the apoptosis-related proteins caspase-3 and poly (ADP-ribose) polymerase. These results demonstrate that the PLEA has neuroprotective effects against oxidative stress (H 2 O 2 )–induced neuronal cell death via its antioxidant and anti-apoptotic properties. PLEA should be investigated in an in vivo model on its potential to prevent or ameliorate neurodegenerative disease.

Panax ginseng C.A. Meyer has been traditionally consumed to prevent or treat various medical disorders due to its diverse health benefits. Polysaccharides isolated from Panax ginseng have been known to possess various pharmacological activities, including immune modulating, anti-diabetic, and anti-obesity properties. Despite the increasing number of reports on the bioactivities of ginseng polysaccharides, little is known regarding the medicinal potential of ginseng-derived oligosaccharides. In this study, we prepared a lower-molecular weight oligosaccharide (GOS, MW. 2.2kDa) from ginseng polysaccharides (MW. 11-605kDa) by enzymatic degradation and evaluated for its immunostimulating activities in RAW 264.7 murine macrophage cells. GOS was shown to be a glucan type oligosaccharide mainly containing glucose residues (97.48 in molar %). Treatment with GOS (100-500μg/ml) dose-dependently enhanced the production of TNF-α, IL-6, and NO in RAW 264.7 cells. Western blot analysis indicated that GOS dose-dependently induced the phosphorylation of c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), p38, and nuclear factor κB (NFκB), which are upstream signalling molecules for cytokine production. While GOS was not cytotoxic to the RAW 264.7 macrophage cells at the concentration tested (up to 1000μg/ml), when B16F10 melanoma cells were co-cultured with the GOS-activated macrophages, the cell viability of melanoma cells was dose-dependently decreased through the induction of apoptotic cell death. Taken together, these results suggested that ginseng marc-derived GOS has anti-cancer activity in vitro against melanoma cells by potentiating macrophage function.

Star-shaped Au nanoparticles (Au nanostars, AuNS) have been developed to improve the plasmonic sensitivity, but their application has largely been limited to single-particle probes. We herein describe a AuNS clustering assay based on nanoscale self-assembly of multiple AuNS and which further increases detection sensitivity. We show that each cluster contains multiple nanogaps to concentrate electric fields, thereby amplifying the signal via plasmon coupling. Numerical simulation indicated that AuNS clusters assume up to 460-fold higher field density than Au nanosphere clusters of similar mass. The results were validated in model assays of protein biomarker detection. The AuNS clustering assay showed higher sensitivity than Au nanosphere. Minimizing the size of affinity ligand was found important to tightly confine electric fields and improve the sensitivity. The resulting assay is simple and fast, and can be readily applied to point-of-care molecular detection schemes.

We report observation of both free and defect-mediated excitonic emissions from temperature-dependent PL study on ZnO/graphene oxide (G-O) nanocomposite grown by ultrasonic assisted spray pyrolysis (UASP). From the temperature-dependent photoluminescence (PL) spectra of the ZnO/G-O nanocomposite, new graphene-related peak was observed at 372 nm along with the exciton transition bound to neutral acceptors or deep donors. The PL intensity of new graphene-related peaks (3.33 eV) become more prominent with increasing G-O concentration, and it was saturated or decreased with the addition of >7.0 wt% of G-O. This feature indicates that new graphene-related states were created below conduction band of ZnO, which supports the excitonic PL enhancement by graphene-embedding is contributed not by charge transfer, but by vacancy filling effect of G-O.

Lanthanide-doped upconverting nanoparticles (UCNPs) have recently attracted enormous attention in the field of biological imaging owing to their unique optical properties: (1) efficient upconversion photoluminescence, which is intense enough to be detected at the single-particle level with a (nonscanning) wide-field microscope setup equipped with a continuous wave (CW) near-infrared (NIR) laser (980 nm), and (2) resistance to photoblinking and photobleaching. Moreover, the use of NIR excitation minimizes adverse photoinduced effects such as cellular photodamage and the autofluorescence background. Finally, the cytotoxicity of UCNPs is much lower than that of other nanoparticle systems. All these advantages can be exploited simultaneously without any conflicts, which enables the establishment of a novel UCNP-based platform for wide-field two-photon microscopy. UCNPs are also useful for multimodal in vivo imaging because simple variations in the composition of the lattice atoms and dopant ions integrated into the particles can be easily implemented, yielding various distinct biomedical activities relevant to magnetic resonance imaging (MRI), computed tomography (CT), and positron emission tomography (PET). These multiple functions embedded in a single type of UCNPs play a crucial role in precise disease diagnosis. The application of UCNPs is extended to therapeutic fields such as photodynamic and photothermal cancer therapies through advanced surface conjugation schemes.

BaO-P2O5 (BP) and BaO-La2O3-Al2O3-P2O5 (BLAP) glass thin films with a thickness of 80–160 nm, which have a high content of residual moisture and a high concentration of non-bridging oxygen (NBO) as a medium for proton movement, were fabricated through sol-gel spin coating using water as a solvent. All the fabricated glass thin films exhibited amorphous phase and glassy, defect-free surfaces. The thickness of the BP thin films decreased as the annealing temperature increased. The increase in the annealing temperature led to a decrease in NBO/BO ratio which is thought to affect proton mobility and an increase in mobile proton concentration. Therefore, it seems that high proton concentration by residual water appears to have a dominant effect on fast proton conduction. The calculated proton concentrations of the fabricated BP thin films were decreased from 55.9 mol/l to 45.5 mol/l as the annealing temperature increased from 300 °C to 400 °C. The conductivity of BP and BLAP thin films annealed at 400 °C were 2.52 × 10−6 S/cm and 1.32 × 10−5 S/cm, respectively, at 300 °C. BLAP thin film showed significantly improved conductivity compared to those of BP glass thin films due to its high proton concentration.