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In this study, reduced graphene oxide (rGO) hybridized high internal phase emulsions were developed and polymerized as porous carriers for aptamer (5’/5AmMC6/-AGT CCG TGG TAG GGC AGG TTG GGG TGA CT-3’) modification to enrich human α-thrombin from serum. The structure and properties of the materials were confirmed by scanning electron microscope (SEM), Fourier transform infrared spectroscope (FT-IR), and X-ray photoelectron spectra (XPS). The adsorption ability and selectivity were studied and the thrombin was detected with liquid chromatography-mass spectrometry (LC–MS). The adsorption of thrombin onto the sorbent was achieved within 30 min and the desorption was realized using 5.0 mL of acetonitrile/water (80/20, v/v). The thrombin was quantified by LC–MS according to its characteristic peptide sequence of ELLESYIDGR.

Aims/Introduction To explore the potential role of irisin in the outcomes of newly diagnosed prediabetes. Materials and Methods Data were obtained from the Guiyang subcenter of the Risk Evaluation of cAncers in Chinese diabeTic Individuals: a lONgitudinal (REACTION) study. A total of 2,530 participants had newly diagnosed prediabetes at baseline and completed follow up. The nested 1:1 case–control study included 161 participants who developed diabetes mellitus at follow up, and 161 age‐ and sex‐matched controls. The follow‐up study included 86 matched case–control pairs. Fasting serum irisin levels were measured using enzyme‐linked immunosorbent assay. Results Baseline serum irisin levels were higher in the cases than in the controls (P = 0.002); high baseline serum irisin levels were an independent risk factor for the development of diabetes (odds ratio 1.235, 95% confidence interval 1.025–1.488). After adjustment for age, sex, body mass index, glycated hemoglobin (HbA1c), smoking, exercise, and family history of diabetes, subjects in the highest quartile of irisin levels had a higher risk of diabetes than those in the lowest quartile (odds ratio 3.065, 95% confidence interval 1.511–6.218). The extent of decrease in irisin levels during follow‐up was greater in the cases than in the controls (P, This is the first longitudinal study to investigate the potential role of irisin in the outcomes of newly diagnosed prediabetes and whether it can be a predictor of diabetes in prediabetic individuals. We believe that our study makes a significant contribution to the literature, because we found a clear association between serum irisin levels and the outcomes of newly diagnosed prediabetes.

The development of sensitive fluorescence sensors and efficient preparation of samples is a challenge in the detection of pesticides in complex samples. In this study, multicolor nitrogen dots (M-Ndots) were synthesised via microwave irradiation at 140 °C for 10 min with 5-amino-1H-tetrazole and p-phenylenediamine as precursors, which have a high fluorescence quantum yield of up to 31%. Furthermore, the M-Ndots were employed as fluorescence sensors for pesticide detection by being combined with a gas membrane separation device, to eliminate the interference from the complex sample matrix. In this process, the M-Ndots were used for sensing thiram and chlorpyrifos through their affinities to Cu2+ and Fe3+, respectively. Because thiram could decompose into volatile CS2, its derivate was sensed using the fluorescence of M-Ndots via a complexation reaction with Cu2+. Chlorpyrifos, due to its volatility, can reduce the Fe3+ ion by inhibiting the activity of acetylcholinesterase, which produces H2O2 to oxidise Fe2+. In a real application, the time consumption for 96 samples was less than 30 min in one run of the gas membrane separation device. The recoveries for thiram and chlorpyrifos ranged from 90.0% to 115.0%, and the analytical results were validated using LC-MS/MS methods, with relative errors ranging from −7.4% to 10.1%.

In this work, graphene oxide-hybridized high internal emulsion polymers with crosslinking and open-cell structure was prepared and applied for separation and enrichment of estrogens. The prepared graphene oxide-hybridized high internal emulsion polymer monoliths had hydrophobicity, porosity and stability, which were just obtained by one step in-situ emulsion polymerization of 2-ethylhexyl acrylate, glycidyl methacrylate, and divinylbenzene after doping with graphene oxide. Benefit from the advantages of its unique character, the graphene oxide-hybridized high internal emulsion polymers monolith with low background pressure (85 kPa) and high mechanical strength could be applied for efficient separation for trace estrogens in urine. Under the optimized condition, trace estrogens, including estrone, estradiol, and diethylstilbestrol in urine, were detected by high-performance liquid chromatography, all the sample preparation process were carried out in 15 min, the recovery rate was ranged from 85.0 to 106.0% and the relative standard deviation was less than 4.

Owing to the remarkable physicochemical properties such as hydrophobicity, conductivity, elasticity, and light weight, graphene-based materials have emerged as one of the most appealing carbon allotropes in materials science and chemical engineering. Unfortunately, pristine graphene materials lack functional groups for further modification, severely hindering their practical applications. To render graphene materials with special characters for different applications, graphene oxide or reduced graphene oxide has been functionalized with different organic agents and assembled together, via covalent binding and various noncovalent forces such as π-π interaction, electrostatic interaction, and hydrogen bonding. In this review, we briefly discuss the state-of-the-art synthetic strategies and properties of organic-functionalized graphene-based materials, and then, present the prospective applications of organic-functionalized graphene-based materials in sample preparation.

It remains a significant challenge for fast and high-throughput detection of trace analytes in complex samples with surface-enhanced Raman scattering (SERS) strategy due to the severe interference from matrices. In this work, a miniaturized array gas membrane separation (AGMS) device coupled with SERS was designed and drew up to eliminate matrix influence and improve the reproducibility of SERS signal during real sample analysis. The design of miniaturized AGMS tube was optimized based on quantitative calculation of its air permeability by computational fluid dynamics simulation. A 10 mm height tube was selected as an optimized design with a recovery of 98.3% for acetaldehyde. The practical feasibility of miniaturized AGMS was validated based on the applications in biochemical analysis and food analysis, such as albuminuria and acetaldehyde in urine sample and metaldehyde and thiram in food samples. The results showed that SERS responses of all analytes dramatically increased by eliminating sample matrices after miniaturized AGMS process. Acetaldehyde, albuminuria, metaldehyde and thiram in real samples could be accurately quantified with recoveries of 82.0–123.3%, and the analytical results were validated by corresponding standard methods with relative error ranging from −4.8% to 5.3%. Time consumption of miniaturized AGMS-SERS for one real sample analysis including sample preparation and determination was less than 20 min and could treat 96 samples with 45 min in one run. It is potential that the miniaturized AGMS technique automated by implementation with a robotic arm could greatly expand the range and accelerate the speed of SERS analysis.

It has been remained a challenge to detect trace formaldehyde in complex samples, such as rice flour and duck blood products. In this study, a purge-trap device was designed and used for volatile target detection, which avoided interference adsorptions on enhanced particle surfaces during subsequent surface-enhanced Raman spectroscopy (SERS) analysis. The device produced a low detection limit for formaldehyde of 1 × 10−4 μg/mL in the concentration ranges of 4 × 10−3–4 μg/mL and 1 × 10−4–3 × 10−3 μg/mL. In the process of the detection of duck blood and rice flour, partial least squares regression (PLSR) was adopted for sample analysis. The formaldehyde concentration was calculated and compared to the actual value from the above model with R2 of 0.97, which indicated high accuracy and stability. These results suggested that the proposed method was reliable and suitable for rapid analysis of trace formaldehyde in real products.

A porous carbon absorbent was obtained by using high internal phase emulsions (HIPEs) polymerization followed by high temperature carbonization under nitrogen protection. Graphene oxide (GO) and silica nanoparticles were doped into the HIPEs to enhance the adsorption ability and reusability. Fourier infrared spectroscopy, X-ray photoelectron spectroscopy and scanning electron microscopy were used for characterization and several parameters of separation and enrichment of trifluralin. The results showed that a hyper-crosslink framework material was obtained with abundant porous (pore size of about 30 μm) and a good adsorption and separation efficiency. The adsorption rate was up to 100% and trifluralin was completely eluted from the absorbent by 2.0 mL of an acetic acid-acetonitrile mixture. Graphical abstractSchematic representation of synthesis of porous carbon absorbent by GO and SiO

Polysilsesquioxanes (PSQ)-based core–shell fluorinated polyacrylate/silica hybrid latex coatings were synthesized with PSQ latex particles as the seeds, and methyl methacrylate, butyl acrylate, 3-(trimethoxysilyl) propyl methacrylate (MPS)-modified SiO2 nanoparticles (NPs), 1H,1H,2H,2H-perfluorooctyl methacrylate (PFOMA) as the shell monomers by emulsifier-free miniemulsion polymerization. The results of Fourier transform IR spectroscopy, transmission electron microscopy, and dynamic light scattering suggested the obtained hybrid particles emerged with trilayer core–shell pattern. Contact angle analysis, x-ray photoelectron spectroscopy, and atom force microscopy results indicated that the hybrid film containing SiO2 NPs showed higher hydrophobicity, lower surface free energy and water absorption, in comparison with the control system (without SiO2 NPs). Compared with the control system, the hybrid latex film containing SiO2 NPs in the fluorinated polyacrylate shell layer showed the higher content of fluorine atoms and a rougher morphology on the film surface. Additionally, thermogravimetric analysis demonstrated the enhanced thermostability of PSQ-based nanosilica composite fluorinated polyacrylate latex film.

In milk and milk products, the matrix is complex and the interfering components are large, so it is difficult to separate and enrich formaldehyde. In this study, combined with Surface-Enhanced Raman Scattering (SERS) technology, the self-developed green capture device was used to realize the integration of separation, enrichment and detection of formaldehyde. Firstly, we use fluid dynamics to simulate the heat-fluid coupling working mechanism of the enrichment chemical mechanical device. By exploring the steady-state and transient changes of separation and enrichment gas flow under different working conditions, we designed a purge and separation device with small dead volume and high separation efficiency. We further optimized the purge air velocity and heating voltage to increase sample recovery and shorten the separation and enrichment time of the target. As a result, we have realized the application of green and efficient pre-treatment, which is rapid and green. Finally, we used derivatization strategy to enhance the Raman scattering and combined with colloidal gold nanoparticles (AuNPs) to realize SERS analysis. According to this method, we detected formaldehyde in boxed milk, milk powder and raw milk. Thus, we realized a rapid detection method of formaldehyde in milk from various sources, including exogenous and endogenous formaldehyde.

In this study, amphiphilic and porous copolymers were successfully prepared by doping a carboxylated carbon nanotube aqueous phase into a styrene and divinylbenzene oil phase, followed by a simple thermal polymerization to form high internalphase emulsions (polyHIPEs-CNTs). Hypercrosslinking and interconnecting chambers were formed with abundant open-cell pores with sizes ranging from 400 nm to 3.0 µm. Infrared spectroscopy, scanning electron microscopy, water contact angle measurements, and adsorption–desorption measurements were used to evaluate the characteristics of the material. The synthesized copolymers were demonstrated to be suitable for the separation of triazine herbicides from soil under optimized operating conditions. The maximum adsorption capacities of simazine, prometon, and prometryn were 25.4, 26.5, and 27.8 µg/g, respectively; the mean recoveries ranged from 87.56 to 97.67%, with a relative standard deviation lower than 4.5%. The polymers were stable, and the adsorption and desorption of the triazine herbicides were completed within a short period (10 min) without obvious interference. Adsorption isotherms revealed that the adsorption was co-determined by multiple effects between the adsorbents and compounds. An excellent reuse performance was observed, and the proposed polymers were believed to be potential materials for sample pretreatment in environmental science and pollutant cleaning engineering.

It still remains a great challenge for quantification of trace analytes in complex samples by surface-enhanced Raman scattering (SERS) technique due to potential matrix influence or weak SERS responses of analytes. In this work, a miniaturized thermal-assisted purge-and-trap (MTAPT) device was designed and developed to eliminate matrix influence coupled with derivatization method before SERS analysis. The design of MTAPT chamber was optimized based on quantitative calculation of its dead volume by computational fluid dynamics simulation. The small straight chamber was selected as an optimized design with a recovery of 96.1% for formaldehyde. The practical feasibility of MTAPT was validated based on four real analytical applications including phenthiol in industrial water, formaldehyde in flour, sulfion in wastewater, and methanol in industrial alcohol. The results showed that SERS responses of all analytes dramatically increased by eliminating sample matrices after MTAPT process. Phenthiol, formaldehyde, sulfion, and methanol in real samples could be accurately quantified with recoveries of 80.9-110.0%, and the analytical results were validated by corresponding standard methods. The time consumption of MTAPT-SERS for real sample analysis including sample preparation and determination was within 16 min. It is highly expected that the combination of MTAPT technique with portable SERS instrument can greatly expand the range of SERS analysis. The proposed MTAPT-SERS method has high potential for on-site analysis of complex samples.

Objective This study evaluated the association of serum irisin level with thyroid autoantibody (TAA) positivity and subclinical hypothyroidism (SH). Methods In this cross-sectional study, 334 participants were assigned to one of the following four age- and sex-matched groups: TAA plus SH (84 patients), isolated TAA (83 patients), isolated SH (83 patients), or healthy controls (84 individuals). Irisin and creatine kinase (CK) were measured in serum samples. Results Patients with TAA plus SH, isolated TAA, and isolated SH had higher irisin levels compared with the controls. There was a significant increase in the irisin level in the TAA plus SH group compared with the control group. Among all participants, the irisin levels were positively associated with thyroglobulin and thyroid peroxidase antibody titers and high-density lipoprotein cholesterol levels, but negatively associated with waist circumference, glycated hemoglobin levels, and fasting plasma glucose levels. The irisin level was not associated with the thyroid-stimulating hormone, free thyroxine, or CK levels. Irisin levels were independently associated with TAA, with or without SH, but they were not associated with SH alone. Conclusions Irisin level may help to predict the risk of developing TAA with or without SH.

Electrospun reduced graphene oxide/TiO2/poly(acrylonitrile-co-maleic acid) composite nanofibers (E-spun RGO/TiO2/PANCMA NFs) were fabricated using electrospinning of the dispersive solution of PANCMA, GO and TiO2 followed by post-chemical reduction. The obtained composite nanofibers were compressed in a dialyzer and then used to absorb and degrade malachite green (MG) and leucomalachite green (LMG) from aqueous solution. Compared to the E-spun TiO2/PANCMA and GO/TiO2/PANCMA NFs, the E-spun RGO/TiO2/PANCMA NFs exhibited higher adsorption capacity and photocatalytic degradation ability. Under optimized conditions, 90.6% of MG and 93.7% of LMG from 50 mL aqueous sample solution were adsorbed on the RGO/TiO2/PANMA NFs (3.0 mg fibers) in 2.0 min, and subsequent the 91.4% and 95.2% of MG and LMG adsorbed on the NFs were degradated in 60 min under UV irradiation, respectively. In addition, the E-spun RGO/TiO2/PANMA NFs exhibited good reusability and could be reused in multiple cycles of operations for adsorption and photocatalytic degradation of MG and LMG. This work demonstrated that the electrospun composite nanofibers are promising materials for removal of pollutants from environmental water samples.

Aflatoxins are highly toxic mycotoxin contamination, which pose serious food safety incidents. It is very important to precisely and rapidly determine trace aflatoxins in food. In this study, we designed porous monolithic column based on covalent cross-linked polymer gels for online extraction and analysis of trace aflatoxins in food samples with complicated matrices coupled with high-performance liquid chromatography-ultraviolet detector (HPLC-UV). The prepared monolithic column showed excellent enrichment performance due to its good permeability, good reproducibility and long life span. The study of adsorption mechanism suggested that the excellent enrichment performance of this monolithic column was attributed to the multiple effect of π-π stacking interaction, hydrophobic effect and steric effect. When the online analytical method was applied for the determine of trace aflatoxins in real food samples, aflatoxins G1 and aflatoxins B1 could be actually found in one positive bean sauce sample and quantified to be 32.8 and 26.4 μg/kg, respectively. Aflatoxins G1 in one bean sample could be also found and quantified to be 25.9 μg/kg. The low detection limits of the developed method were achieved in range of 0.08-0.2 μg/kg. And the recoveries for spiked samples were in range from 76.1 to 113% with RSDs of 1.1-9.6%. The developed method was proved to be a promising method for online enrichment and analysis of trace aflatoxins in complicated food samples.

A new class of solid-phase extraction column prepared with grafted mercapto-silica polymerized high internal phase emulsion particles was used for the preconcentration of trace lead. First, mercapto-silica polymerized high internal phase emulsion particles were synthesized by using high internal phase emulsion polymerization and carefully assembled in a polyethylene syringe column. The influences of various parameters including adsorption pH value, adsorption and desorption solvents, flow rate of the adsorption and desorption procedure were optimized, respectively, and the suitable uploading sample volumes, adsorption capacity, and reusability of solid phase extraction column were also investigated. Under the optimum conditions, Pb(2+) could be preconcentrated quantitatively over a wide pH range (2.0-5.0). In the presence of foreign ions, such as Na(+) , K(+) , Ca(2+) , Zn(2+) , Mg(2+) , Cu(2+) , Fe(2+) , Cd(2+) , Cl(-) and NO3 (-) , Pb(2+) could be recovered successfully. The prepared solid-phase extraction column performed with high stability and desirable durability, which allowed more than 100 replicate extractions without measurable changes of performance. The feasibility of the developed method was further validated by the extraction of Pb(2+) in rice samples. At three spiked levels of 40.0, 200 and 800 μg/kg, the average recoveries for Pb(2+) in rice samples ranged from 87.3 to 105.2%.

A novel large-volume immobilized enzyme reactor (IMER) on small column was prepared with organic-inorganic hybrid silica particles and applied for fast (10 min) and oriented digestion of protein. At first, a thin enzyme support layer was formed in the bottom of the small column by polymerization with α-methacrylic acid and dimethacrylate. After that, amino SiO2 particles was prepared by the sol-gel method with tetraethoxysilane and 3-aminopropyltriethoxysilane. Subsequently, the amino SiO2 particles were activated by glutaraldehyde for covalent immobilization of trypsin. Digestive capability of large-volume IMER for proteins was investigated by using bovine serum albumin (BSA), cytochrome c (Cyt-c) as model proteins. Results showed that although the sequence coverage of the BSA (20%) and Cyt-c (19%) was low, the large-volume IMER could produce peptides with stable specific sequence at 101-105, 156-160, 205-209, 212-218, 229-232, 257-263 and 473-451 of the amino sequence of BSA when digesting 1mg/mL BSA. Eight of common peptides were observed during each of the ten runs of large-volume IMER. Besides, the IMER could be easily regenerated by reactivating with GA and cross-linking with trypsin after breaking the -C=N- bond by 0.01 M HCl. The sequence coverage of BSA from regenerated IMER increased to 25% comparing the non-regenerated IMER (17%). 14 common peptides. accounting for 87.5% of first use of IMER, were produced both with IMER and regenerated IMER. When the IMER was applied for ginkgo albumin digestion, the sequence coverage of two main proteins of ginkgo, ginnacin and legumin, was 56% and 55%, respectively. (Reviewer 2) Above all, the fast and selective digestion property of the large-volume IMER indicated that the regenerative IMER could be tentatively used for the production of potential bioactive peptides and the study of oriented protein digestion.

In this study, an easy and efficiency protein digestion method called continuous microwave-assisted protein digestion (cMAED) with immobilized enzyme was developed and applied for proteome analysis by LC-MS(n). Continuous microwave power outputting was specially designed and applied. Trypsin and bromelain were immobilized onto magnetic micropheres. To evaluate the method of cMAED, bovine serum albumin (BSA) and protein extracted from ginkgo nuts were used as model and real protein sample to verify the digestion efficiency of cMAED. Several conditions including continuous microwave power, the ratio of immobilized trypsin/BSA were optimized according to the analysis of peptide fragments by Tricine SDS-PAGE and LC-MS(n). Subsequently, the ginkgo protein was digested with the protocols of cMAED, MAED and conventional heating enzymatic digestion (HED) respectively and the LC-MS(n) profiles of the hydrolysate was compared. Results showed that cMAED combined with immobilized enzyme was a fast and efficient digestion method for protein digestion and microwave power tentatively affected the peptide producing. The cMAED method will be expanded for large-scale preparation of bioactive peptides and peptide analysis in biological and clinical research.

Microwave-assisted enzymatic digestion (MAED) technique was applied for ginkgo protein digestion with both free and immobilized enzyme. Under the optimized conditions of MAED (0.01 g/mL substrate concentration of bromelain, 4500 U/g enzyme/ginkgo protein, 30 min, 300 W microwave power), a higher digestion rate (7.50%) and a significant increase in antioxidant activity (72.7 mg/g) were obtained in contrast with the conventional methods. With the optimized digestion conditions (0.625% glutaraldehyde (v/v), 0.4 mg/mL initial concentration of bromelain and 4 h of immobilization), the activity and effectiveness factor of immobilized bromelain were respectively 86 U and 81.6%. The results of ginkgo digestion by applying MAED indicated that the digestion rate of immobilized bromelain obtained by MAED method (6.41%) was comparable to that of free bromelain in the conventional digestion (8.13%). In both case with immobilized and free bromelain while applying MAED, a homogeneously abundant distribution of peptide fragments (from 7.863 Da to 5856 Da) and a few different peptide profiles were found. This report brings in conclusion that applying MAED with immobilized enzyme has the potential to obtain the highest number of antioxidant activity peptides.

The Arabidopsis Ethylene-Insensitive 2 (EIN2) gene was shown to be involved in the regulation of abiotic and biotic stresses, such as ozone stress, high salt, oxidative stress, lead and disease resistances. However, it is unclear whether EIN2 plays a role in mediating the ultraviolet (UV)-B response in Arabidopsis. Here, we show that EIN2 is involved in the regulation of the UV-B response. The EIN2 expression was repressed by UV-B exposure, and ein2-1 mutant plants were more tolerant to UV-B than wild-type plants, as indicated by analysis of survival rates. Significant higher increases in flavonoids and anthocyanins were detected in ein2-1 plants than in wild-type plants treated with or without UV-B treatment, which was associated, at least in part, with constitutively increased transcript levels of two key genes CHALCONE SYNTHASE (CHS) and CINNAMATE 4-HYDROXYLASE (C4H) involved in the biosynthesis pathway of flavonoid and anthocyanins. These results suggest that EIN2 mediates the UV-B response, at least in part, via the modulation of expression of CHS and C4H genes.

As sessile organisms, plants usually experience several stresses simultaneously. It was shown that stress cross-tolerance may be induced by different stressors, including biotic factors as well as heavy metal, hypoxia, ultraviolet-B radiation, heat, high salt, drought, and cold stresses. However, it is unclear whether there is a cross-tolerance toward cold and lead (Pb) stresses in Arabidopsis. In this study, we showed that cold pretreatment enhanced Pb(II) resistance in Arabidopsis, as indicated by lower reduction of root length, fresh weight, and chlorophyll content in the cold-treated plants than the control ones. In the cold-treated seedlings, lower Pb contents were detected in roots and shoots in comparison to the control. This was associated, at least in part, with the activation of the expression of AtPDR12 gene, a pump excluding Pb(II) and/or Pb(II)-containing toxic compounds from the cytoplasm to the exterior of the cell. This finding was further supported by genetic evidence showing that cold treatment was unable to enhance resistance of atpdr12 mutant to Pb(II) stress but could enhance Pb(II) resistance of the wild type. In addition, we also found that cold-induced enhanced Pb(II) resistance was glutathione-independent. Taken together, all these results suggest that cold treatment enhanced Pb(II) resistance in Arabidopsis, at least in part, by activating the expression of AtPDR12 gene.

The Arabidopsis Ethylene-Insensitive 2 (EIN2) gene has been shown to be involved in the regulation of abiotic and biotic stresses, including ozone stress, high salt, oxidative stress and disease resistance. However, little is known about the role of EIN2 gene in lead (Pb) resistance in Arabidopsis. In this study, we showed that EIN2 gene is required for Pb(II) resistance in Arabidopsis. EIN2 gene was induced by Pb(II) treatment, and the ein2-1 mutant showed enhanced sensitivity to Pb(II). A higher Pb content was detected in ein2-1 plants than in wild-type plants when subjected to Pb(II) treatment, which was associated, at least in part, with reduction in expression of AtPDR12 gene, a pump excluding Pb(II) and/or Pb(II)-containing toxic compounds from the cytoplasm. Moreover, the ein2-1 mutation also impaired glutathione (GSH)-dependent Pb(II) resistance, which was related to constitutive reduction of express of GSH1 gene involved in GSH synthesis and consequently reduced GSH content. Taken together, all these results suggest that EIN2 gene mediates Pb(II) resistance, at least in part, through two distinct mechanisms, a GSH-dependent mechanism and a GSH-independent AtPDR12-mediated mechanism.

Potassium (K+) is an essential element for plant growth and development. Under low-K+ stress, Arabidopsis (Arabidopsis thaliana) plants show K+-deficient symptoms, typically leaf chlorosis and subsequent inhibition of plant growth and development. The non-protein amino acid β-amino-butyric acid (BABA) has been shown to have roles in protecting Arabidopsis against various pathogens as well as drought, high salinity, and cadmium stresses; However, little is known about the role of BABA in protecting Arabidopsis against low-K+ stress. Here, we showed that BABA protects Arabidopsis against low-K+ stress by increasing K+ uptake under low-K+ condition. Leaf chlorosis of plants subjected to low-K+ stress was abolished by BABA pretreatment, as indicated by a lower reduction in chlorophyll content in BABA-treated plants than water-treated plants. Low-K+ stress-induced decreases in both lateral root length and the numbers of lateral roots were improved by BABA pretreatment. In addition, under low-K+ stress, a significantly higher K+ concentration was detected in BABA-pretreated plants than in water-treated plants, and the transcript levels of AtHAK5 and LKS1 genes involved in K+ uptake in BABA-treated plants were higher than those of water-treated plants. Taken together, our results suggest that BABA plays a role in enhancing low-K+ stress tolerance by increasing K+ uptake, at least in part, via modulation of AtHAK5 and LKS1 under low-K+ condition.

Retinol binding-protein 4 (RBP4), a recently identified adipokine and retinol transporter, has been shown to play a causative role in insulin resistance, an underpinning between obesity and colon neoplasia. Yet, the relationship between RPB4 and cancer, including colon neoplasia is largely unexplored. We carried out a cross-sectional study to determine the risk association between RBP4 and colon adenomas. We determined pre-diagnostic serum levels of RBP4 in 626 patients undergoing screening colonoscopies from January 2006 to March 2007. The cases had statistically significant higher levels of RBP4 than the controls (58.5µg/mL ± 38.2 vs. 51.9µg/mL ± 32.5, p=0.03). Multivariate logistic regression model revealed a statistically significant overall association of RBP4 with risk of colon adenoma (OR = 3.10 for each increment of 35µg/mL, CI = 1.15 – 8.66; p = 0.03). Stratified analysis by the median BMI showed that the risk association was largely limited to those with BMI < 27.8 kg/m2. Compared to those in the bottom tertile of RBP4, the ORs for the 2nd and 3rd tertiles were 1.84 (CI = 0.89–3.8) and 2.14 (CI = 1.08–4.23) respectively (p for trend = 0.03); there was little evidence for such an association among those with BMI ≥ 27.8 kg/m2. This is the first study to show colon adenoma risk association with high circulating levels of RBP4. Further study is merited to investigate the mechanism that underlies the RBP4-colon neoplasia link.