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A new convenient method for identifying colorant compounds (CCs) in food matrices was developed using high-performance liquid chromatography with a diode array detector and quadrupole-time-of-flight mass spectrometer (HPLC-DAD-Q/TOF-MS) combined with theoretical calculations. A model sample containing three typical CCs was completely separated via HPLC-DAD. The obtained 3D ultraviolet-visible (UV-vis) spectra revealed the maximum absorption wavelengths (MAWs) of all CCs (yellow, 430 nm; red, 520 nm; blue, 620 nm) in the range of 400-800 nm, and their colors were determined based on their MAWs. Temporary structures of the CCs were obtained using Q/TOF-MS analysis. Theoretical calculations were then performed to obtain the theoretical MAWs and colors of the CCs according to their calculated UV-vis spectra based on temporary structures. The structures of the CCs were confirmed without the need for authoritative standards by comparing the consistency between their experimental and theoretical MAWs and colors. This method is particularly suitable for identifying CCs or compounds with UV-Vis absorption, including new compounds, compounds for which standards are difficult to obtain, and known compounds without reporting relevant molecular information.

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Light-flavor Baijiu (LFB) is widely cherished for its flavor. This study identified the thresholds of 14 aroma compounds in a 52% ethanol-water matrix and conducted a comprehensive analysis of the interactions among key aroma compounds in LFB using the Feller additive model and odor activity values approach. Among them, the interactions of ß-damascenone with ester and alcohol compounds were primarily promotive, while the interaction with acid compounds was predominantly masking. Furthermore, for the first time, the electroencephalogram (EEG) technology was used to characterize the interactions between aroma compounds. The results showed that the brain activity in the alpha frequency band demonstrated heightened olfactory sensitivity. The EEG could not only display the additive effect of odor intensity but also reflect the differences in aroma similarity between different odors. This study demonstrated that the EEG can serve as an effective tool for olfactory assessment.

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Organic Na-montmorillonite (OMt-12-2-12·2Y - , Y=CH 3 CO 3 - , C 6 H 5 COO - and Br - ) modified by a series of Gemini quaternary ammonium surfactants with different counterions was prepared for enhancing the adsorption capacity of methyl orange. Compared with the initial adsorption capacity of 5.251 mg/g of Na-Mt, the adsorption effect of OMts under the optimal conditions increased by about 31~34 times. The adsorption isotherms and kinetics of all adsorption processes were respectively described by Langmuir and pseudo-second-order models. The structure, hydrophobicity and hydration of the counterions, as well as the affinity of the counterions with the long aliphatic chains, had a certain influence on the adsorption performance of OMts for methyl orange.

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Background: Atherosclerosis (AS) is a pathological vascular disorder responsible for the majority of cardiovascular deaths. Sarsasapogenin (Sar) is a natural steroidal compound which has been extensively applied to multiple human diseases due to its pharmacological properties. In the present paper, the impacts of Sar on oxidized low-density lipoprotein (ox-LDL)-treated vascular smooth muscle cells (VSMCs) and its possible action mechanism were investigated. Methods: Firstly, Cell Counting Kit-8 (CCK-8) estimated the viability of VSMCs following treatment with ascending doses of Sar. Then, VSMCs were treated by ox-LDL to stimulate an in vitro cell model of AS. CCK-8 and 5-Ethynyl-2'-deoxyuridine (EDU) assays were used to assess cell proliferation. Wound healing and transwell assays were applied to measure the migratory and invasive capacities, respectively. The expression of proliferation-, metastasis-, and stromal interaction molecule 1 (STIM1)/Orai signaling-associated proteins was measured by western blot. Results: The experimental data illuminated that Sar treatment noticeably protected against ox-LDL-elicited VSMCs proliferation, migration, and invasion. Besides, Sar lowered the elevated STIM1 and Orai expression in ox-LDL-treated VSMCs. Further, STIM1 elevation partially abrogated the impacts of Sar on the proliferation, migration, and invasion of VSMCs challenged with ox-LDL. Conclusions: In conclusion, Sar might reduce STIM1 expression to impede the aggressive phenotypes of ox-LDL-treated VSMCs.

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The discharge of industrial phenol pollutants causes great harm to the natural environment and human health. In this study, phenol removal from water was studied via the adsorption of Na-montmorillonite (Na-Mt) modified by a series of Gemini quaternary ammonium surfactants with different counterions [(C11H23CONH(CH2)2N+ (CH3)2(CH2)2 N+(CH3)2 (CH2)2NHCOC11H23·2Y-, Y = CH3CO3-, C6H5COO- and Br-, 12-2-12·2Y-]. The results of the phenol adsorption indicated that MMt-12-2-12·2Br-, MMt-12-2-12·2CH3CO3- and MMt-12-2-12·2C6H5COO- reached the optimum adsorption capacity, which was 115.110 mg/g, 100.834 mg/g and 99.985 mg/g, respectively, under the conditions of the saturated intercalation concentration at 2.0 times that of the cation exchange capacity (CEC) of the original Na-Mt, 0.04 g of adsorbent and a pH = 10. The adsorption kinetics of all adsorption processes were in good agreement with the pseudo-second-order kinetics model, and the adsorption isotherm was better modeled by Freundlich isotherm. Thermodynamic parameters revealed that the adsorption of phenol was a physical, spontaneous and exothermic process. The results also showed that the counterions of the surfactant had a certain influence on the adsorption performance of MMt for phenol, especially the rigid structure, hydrophobicity, and hydration of the counterions.

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To overcome the problems of incomplete flavor components from Piper nigrum extract and the Piper nigrum product easy deterioration in the storage process, microcapsules of the whole Piper nigrum were prepared by spray-drying combined with enzymatic hydrolysis. Under the best conditions for the microencapsulation obtained by the response surface methodology, which have been determined as the ratio of core and wall material (1:0.2, w/w), proportion of wall materials (starch sodium octenyl succinate : maltodextrin : xanthan gum) (1:1:0.2, w/w/w), wall material concentration (11%, w/v) and inlet air temperature (180°C), the embedding rate of the prepared Piper nigrum microcapsules reached 90.21%. Fourier transform infrared spectroscopy, scanning electron microscopy and particle size distribution studies established that the Piper nigrum powder was entrapped within the microcapsules, which had intact morphology and uniform particle size distribution. Besides, gas chromatography-mass spectrometry analysis demonstrated that the prepared Piper nigrum microcapsules could preserve the major of the volatile aroma components of Piper nigrum, carene, D-limonene, α-phellandrene, and (-)-ß-pinene. The obtained results showed that the microcapsules might contribute to the development of preserving original flavor from Piper nigrum and have potential applications in the commodity market.

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The mTOR-dependent nutrient-sensing and response machinery is the central hub for animals to regulate their cellular and developmental programs. However, equivalently pivotal nutrient and metabolite signals upstream of mTOR and developmental-regulatory signals downstream of mTOR are not clear, especially at the organism level. We previously showed glucosylceramide (GlcCer) acts as a critical nutrient and metabolite signal for overall amino acid levels to promote development by activating the intestinal mTORC1 signaling pathway. Here, through a large-scale genetic screen, we find that the intestinal peroxisome is critical for antagonizing the GlcCer-mTORC1-mediated nutrient signal. Mechanistically, GlcCer deficiency, inactive mTORC1, or prolonged starvation relocates intestinal peroxisomes closer to the apical region in a kinesin- and microtubule-dependent manner. Those apical accumulated peroxisomes further release peroxisomal-ß-oxidation-derived glycolipid hormones that target chemosensory neurons and downstream nuclear hormone receptor DAF-12 to arrest the animal development. Our data illustrate a sophisticated gut-brain axis that predominantly orchestrates nutrient-sensing-dependent development in animals.

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The interfacial charge dynamics was crucial for semiconductor heterostructure photocatalysis. Through the rational design of the heterostructure interface, heterojunction expressed variable recombination and migration dynamics for excited carriers. Herein, followed by a typical chemical bath strategy with the hexagonal cadmium sulfide (CdS) overlapped on the exfoliated molybdenum disulfide (MoS2) film, we developed a cadmium sulfide/molybdenum disulfide (CdS-MoS2) nano-heterojunction and investigated the interfacial charge dynamics for photocatalytic hydrogen evolution. Photoelectron spectroscopy detected an energetic offset between CdS and MoS2, revealing the formation of an interfacial electric field with efficient charges separation. Through transient absorption spectra, we demonstrated the type-II contact at the CdS-MoS2 interface. Driven by the electric field, the excited carriers separated and rapidly migrated to sub-band defects of CdS within the first 500 fs. The carriers-restricted defects provided catalytic active sites, endowing CdS-MoS2 a highly efficient photocatalytic capability. Consequentially, the CdS-MoS2 achieved an enhanced hydrogen evolution rate of 2.3 mmol·g-1·h-1 with significantly stronger photocurrent density. This work gave an insight to the channel of interfacial separation and migration for excited carriers, which could contribute to the interfacial engineering of advanced heterojunction photocatalysts.

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A series of amide quaternary ammonium surfactants with the formula C n H2n+1CONH(CH2)2N+(CH3)3·CH3CO3 - (n = 9, 11, 13, 15) were synthesized using a fatty acid, N,N-dimethylethylenediamine, and a green reagent dimethyl carbonate. A comparative study of the four surfactants in terms of surface activity, aggregation characteristics, and foam properties was conducted. The results show that these amide quaternary ammonium surfactants reduce the surface tension of water to a minimum value of 23.69 mN·m-1 at a concentration of 1.55 × 10-4 mol·L-1 and self-assemble spontaneously into aggregates, which are mostly vesicles. Furthermore, with increasing the alkyl chain length, their critical micelle concentration (CMC) values and surface tension values at the CMC (γCMC) decrease and then increase, and the degree of counterion binding (ß) decreases. It is also found that these amide quaternary ammonium surfactants exhibit excellent foam ability and foam stability.

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Developing durable and efficient non-precious-metal based catalysts for oxygen evolution reaction (OER) is highly desirable in the field of electrocatalysis. In this work, a series of novel Mo anchored N-doped carbon catalysts (denoted as Mo/NC-T) were prepared starting from the zeolitic imidazolate framework 8 (ZIF-8) precursor. Firstly, Mo doped ZIF-8 precursor (Mo/ZIF-8) with a regular polyhedron structure was formed through a simple ion-exchange method process between molybdenum pentachloride (MoCl5) and ZIF-8. Afterward, Mo/ZIF-8 was converted to Mo/NC-T through a two-step calcination process in nitrogen (N2) and ammonia (NH3). The as-synthesized Mo/NC-T samples exhibited superior electrocatalytic OER properties. The optimal sample at 650 °C (Mo/NC-650) presented a low overpotential of 320 mV at 10 mA cm-2, a Tafel slope of 71 mV dec-1, and an outstanding long-term stability for 30 h in 1 M KOH solution. The remarkable OER activity of Mo/NC-T could be ascribed to the structural stability of carbon matrix and the synergistic effect between Mo3+ (derived from Mo-C bonds) and pyridinic N. This work provides a novel perspective on the roles of Mo species in the N-doped carbon electrocatalysts for OER.

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Developing durable and efficient photocatalysts for H2 evolution is highly desirable to expedite current research on solar-chemical energy conversion. In this work, a novel photocatalytic H2 evolution system based on Zn0.3Cd0.7S/NiS1.97 nanocomposite was rationally designed for the first time. In this advanced composite structure, NiS1.97 nanosheets as a co-catalyst were intimately coupled to the inner surface of the hollow spherical Zn0.3Cd0.7S. The construction of the hollow spherical shell shortened the distance of charge migration to the surface site and increased the multiple absorption of incident light. The introduction of NiS1.97 nanosheets increased the light absorption capacity of the composite system and also greatly improved the separation and migration behavior of photo-generated carriers due to its narrower band gap and relatively low conduction band position, which had been confirmed by DRS, EIS and PL. As a result, the hollow Zn0.3Cd0.7S/NiS1.97 composite material exhibited excellent photocatalytic activity. At the loading amount of NiS1.97 up to 15 at.%, the hollow Zn0.3Cd0.7S/NiS1.97 composite exhibited the best photocatalytic activity with a corresponding H2 production rate of 22.637 mmol g-1h-1, which was 1.42 times and 1.85 times that of hollow Zn0.3Cd0.7S and solid Zn0.3Cd0.7S, respectively. Moreover, this novel catalyst also displayed a long-term stability without apparent debasement in H2 evolution activity. It is expected that this work could provide new inspiration to the design and development of other highly active photocatalytic systems for water splitting.

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The present study was designed to provide information regarding the influences of pH and inorganic salts on the surface activity of the amido Gemini amine oxide surfactants, the formula of which was C n H2 n +1CONH(CH2)2N+O-(CH3)-(CH2)2-(CH3)N+O-(CH2)2NHCOC n H2 n +1 (n=11, 13, 15, and 17). Their biodegradability was also investigated. The results showed that the critical micelle concentration (CMC) and the corresponding surface tension (γCMC) changed regularly with the increase of the mass concentration of NaCl and CaCl2. The optimal CMC and γCMC can be obtained by adjusting the inorganic salt content. Besides, the CMC near the isoelectric point of the surfactant is higher than the CMC within the isoelectric point. Furthermore, the biodegradability test revealed that the prepared surfactants had good biodegradability which was above 96% after 7 days.

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The specific roles of Ni and Fe in nickel-iron (oxy)hydroxide catalyst (NiFeOx(OH)y) are extensively discussed during oxygen evolution reaction (OER). However, there still remains controversy about whether Ni or Fe species as the dominate active site. In this work, we reported the NiFeOx(OH)y catalysts with varied atomic ratio of nickel and iron for OER to explore the dominate active site during OER processes. From the electrochemical performances, the similar Tafel slopes of catalysts with Fe species can achieve at a level of 40 mV dec-1, outperforming the Tafel slopes of catalysts without Fe species. Thus, it can be concluded that the present Fe site can serve as the dominant active site in NiFeOx(OH)y for OER. Meanwhile, the Ni species is proved as the OH- adsorption site, which is beneficial to the Fe site to deliver a better OER performance. As a result, the catalyst with an optimal Ni/Fe interface (atomic ratio of 1 : 1.18) displays outstanding OER performances. It only requires a low overpotential of 250 mV to deliver current density of 10 mA cm-2 and exhibits a small Tafel slope of 39 mV dec-1. This catalyst also shows remarkable stability with negligible potential decay after 50 h at a current density of 50 mA cm-2. This work offers a new sight into the specific roles of Ni and Fe in NiFeOx(OH)y for OER.

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A series of gemini quaternary ammonium surfactants containing carboxylate counterion with the formula C17H35CONH(CH2)2N+(CH3)2(CH2)2N+(CH3)2(CH2)2 NHCO C17H35·2Y (Y=HCOO-, CH3COO-, CH3CHOHCOO-) have been synthesized by a counterion conversion process and characterized by Fourier transform infrared spectroscopy and mass spectroscopy. It is found that these surfactants reduce the surface tension of water to a minimum value of 26.78 mN·m-1 at a concentration of 1.21 ×10-5 mol·L-1. TEM images reveal that aggregates with vesicles or tubular structure are spontaneously formed in these surfactants aqueous solution with the concentration of 1×10-3 mol·L-1. It is also found that they are effective corrosion inhibitors for A3 steel in acid solution and have superior antibacterial activity at a concentration of 0.1g·L-1.

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Objective To prepare a monoclonal antibody (mAb) against human CD33 by immunizing mice with recombinant vector and analyze its characteristics and clinical application. Methods The eukaryotic expression vector pcDNA3.1(+)/CD33 was constructed and used to immunize mice. The mouse monoclonal antibody against human CD33 was then harvested using the hybridoma technique. Its properties were evaluated and the clinical performance was validated. Results One hybridoma cell line capable of secreting mouse anti-human CD33 monoclonal antibody was successfully obtained, which was named HI33a for clone identification with a subclass of IgG2a, κ. Flow Cytometry analysis revealed that the antibody could stain myeloid cell lines but not lymphoid cell lines, and it could inhibit the binding of similar imported antibodies with HL-60 cells competitively. Western blotting verified that it could bind a Mr 67 000 membrane protein extracted from HL-60 cells, which was a strong indication of the characteristics of CD33 protein molecule. Labeled with PE fluorescein, CD33-PE was tested as an antibody reagent in comparison with other similar imported products. Its overall performance including the accuracy, linearity, and precision all met the industrial standard. Further clinical evaluation of 558 bone marrow samples showed that the results were highly consistent with those by the imported reagents used as controls. Conclusion A hybridoma cell line stably secreting anti-human CD33 mAb was prepared.

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The series of gemini amine-oxide surfactants with the formula C n H2n+1CONH(CH2)2N+O-(CH3)-(CH2)3-(CH3)N+O-(CH2)2NHCOC n H2n+1 (n = 11, 13, 15, and 17) has been synthesized successfully. Their isoelectric point and acid dissociation constant were measured to determine the ionization form of the surfactant molecules in aqueous solution within different pH values. The studies showed that the length of the hydrophobic alkyl chains had a great influence on the pH-stimuli responsive behavior of these surfactants. When n ≤ 13 (n-3-n-OA), the regularity of the pH-stimuli responsive behavior of the surfactant solutions was relatively consistent, while the surfactants with longer hydrophobic alkyl chain lengths lost this regularity (n ≥ 15). In addition, vesicles were observed in most of these surfactant aqueous solutions, with the exception of 11-3-11-OA. Moreover, the obvious flocculation phenomenon was observed within the range of pH 4-5, and they flocculated rapidly when they approached their isoelectric points. This process was reversible, which brought more possibilities for their application in drug delivery and release.

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A group of Gemini quaternary ammonium surfactants with the formula C n H2n+1CONH(CH2)2N+(CH3)2(CH2)2N+(CH3)2(CH2)2 NHCOC n H2n+1 · 2Y (n = 11, 13 and 15, Y = HCOO-, CH3COO- and CH3CHOHCOO-) have been synthesized by a counterion conversion process and characterized by Fourier transform infrared spectroscopy and mass spectroscopy. Their adsorption and self-aggregation properties are investigated by surface tension, conductivity, dynamic light scattering and transmission electron microscopy (TEM) measurements. The results show that these surfactants reduce the surface tension of water to a minimum value of 26.51 mN m-1 at a concentration of 5.72 × 10-2 mmol l-1. Furthermore, the increased alkyl chain length of the carboxylic counterions leads to the increased critical micelle concentration, the decreased degree of counterion binding (ß) and the decreased self-assembly tendency, but the minimum area per surfactant molecule (A min) adsorbed at the air-aqueous solution are similar. TEM images reveal that these surfactants self-assemble spontaneously into aggregates with vesicle or bilayer structures. It is also found that they have superior antibacterial activity at a concentration of 0.1 g l-1. The high surface activity and high antibacterial activity of the Gemini quaternary ammonium salt surfactants containing different carboxylic counterions bring more possibilities for the application in the field of biomedicine.

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BACKGROUND/AIMS: Sinonasal mucosal melanoma (SMM) is a rare but extremely aggressive disease. Interestingly, however, as lethal as SMM, a few patients could survive for over 5 years without metastasis. However, biomarkers for metastatic SMM are lacking. METHODS: Laser-capture microdissection combined with microRNA microarray and RT-qPCR was performed in formalin-fixed paraffin-embedded tissue samples from SMM patients whose follow-up studies were carried out in parallel. In vitro cell proliferation and invasion assays, gelatin zymography, western blot analysis and RT-qPCR were performed in melanoma cell lines. RESULTS: In the discovery stage, miR-4633-5p expressed differentially in sinonasal mucosal melanoma patients with short and long disease-specific survival. Subsequent large-sample validation revealed that expression of miR-4633-5p was lower in metastatic SMM than in non-metastatic patients (P< 0.001). Moreover, miR-4633-5plow was able to identify metastatic SMM with specificity of 100% (5/5) and sensitivity of 87.5% (21/24). Multivariate analysis further pinpointed miR-4633-5p as an independent marker for metastasis (relative risk: 54.22, P< 0.001). In vitro, overexpression of miR-4633-5p suppressed the growth and invasiveness of melanoma cells through inhibiting activation of Akt pathway and secretion of MMP2, while knockdown of miR-4633-5p reversed the inhibitory effects. CONCLUSION: Our findings underpin miR-4633-5p as a predictive biomarker in metastatic SMM and a pivotal tumor suppressor that negatively regulates the invasive growth of melanoma cells. Quantitative detection of miR-4633-5p can diagnostically predict the risk of metastasis in SMM patients, which, in turn, may lead to more personalized treatment with better prognosis.

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Sinonasal mucosal malignant melanoma (SNMMM) is a rare disease. The aim of this study was to investigate the expressions of HER4 and CD44 in human SNMMM tissues and their relationship with the clinicopathological features and prognosis of patients. In total, 64 paraffin-embedded samples of SNMMM treated in our hospital from 29 December 1999 to 24 June 2011 were collected. HER4 and CD44 were detected in the tissues of SNMMM by immunohistochemistry. The differences in the HER4 and CD44 expressions in the tissues were evaluated and matched with clinicopathological parameters and the survival rate, respectively. The positive rates of the HER4 and CD44 expressions were 70.3 and 65.6%, respectively; the positive expression of HER4 was correlated with a positive expression of CD44 (P<0.05). The positive expression of HER4 was correlated with the prognosis of SNMMM patients (P<0.05). There was no significant correlation between a positive expression of CD44 and the prognosis of patients (P>0.05). The expressions of HER4 and CD44 were not significantly correlated with sex, age, pigment, tumor site, etc. (P>0.05). Our results further emphasize a correlation between HER4 and CD44 expressions in SNMMM tissues and point out that a positive HER4 expression might be an important factor in valuing the prognosis of patients with SNMMM.

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Diabetes mellitus is characterized by high blood glucose levels. Increased levels of reactive oxygen species (ROS) may disrupt insulin signaling and result in insulin resistance. The Alpinia oxyphylla extract (AOE) possesses powerful antioxidant activity and may therefore inhibit the development of insulin resistance. The objective of the present study was to determine the effects of AOE on blood glucose, insulin and lipid levels in a type II diabetic nephropathy animal model (C57BIKsj db-/db-). All experiments were performed on male C57BL/Ks DB/DB and db-/db- mice that were left to acclimatize for 1 week prior to the experimental period. AOE was administered to these mice at different dosages (100, 300 and 500 mg/kg) for 8 weeks. The results demonstrated that AOE did not affect mouse weight, while blood glucose concentrations were found to significantly decrease in a dose-dependent manner (P<0.05). The effect of administering 500 mg/kg AOE (AOE500) to db-/db- mice was tested further. Treatment with AOE500 for 8 weeks led to improved glucose tolerance and reduced plasma insulin concentrations (P<0.05), as well as a significant decrease in triglyceride concentrations (P<0.05) and levels of total cholesterol (P<0.05) in db-/db- mice. Furthermore, treatment with AOE500 decreased the concentration of malondialdehyde, elevated the concentration of glutathione and increased the activities of the antioxidant enzymes superoxide dismutase and peroxidase (P<0.05) in the livers of db-/db- mice. Meanwhile, AOE-treated mice exhibited significantly reduced urine albumin, creatinine and blood urea nitrogen excretion (P<0.05). In parallel, the upregulated expression of phosphatase and tensin homolog (PTEN) in the liver and kidneys of db-/db- mice was impaired following AOE500 treatment. The results of the present study suggest that AOE regulates blood glucose and lipid levels and improves renal function by mediating oxidative stress and PTEN expression at the onset of type II diabetes mellitus.