Search

The in vivo and on-site detection of key physiology parameters in plants will be of great relevance for precision agriculture and food technology. In this work, a sensitive enzymatic glutamate sensor was successfully developed. To enhance the conductivity and catalytic ability and to fix the glutamate oxidase, Au-Pt nanoparticles were first deposited on screen-printed electrodes, and then carboxylated graphene oxide and carboxylated multiwalled carbon nanotubes were fabricated for the synthesis of the electrode. The detection range of the glutamate sensor is widest (2 μM to 16 mM) up to date, and its detection limit is relatively low (0.14 μM). A number of standard curves were built in the pH range of 3.5-7.5, which can be applied in various plants and fruits. Using this sensor, the glutamate level in tomatoes was determined in vivo. This glutamate sensor has important practical value in precision agriculture. Our strategy also provides a way to establish the detection modes for other biomolecules in plants.

A novel COOH–GO–COOH–MWNT/pDA/AuNPs based electrochemical aptasensor was developed for detection of AFB1.

Yuanhuacine is a Daphne-type diterpene ortho-ester and is one of the main active ingredients of genkwa flos. Anticancer activity of yuanhuacine has been well investigated in various tumor cells and animal models, but information on metabolism and pharmacokinetics is limited. The aims of the present study were to investigate the metabolic and pharmacokinetic profiles of yuanhuacine in rat. The metabolic profile of yuanhuacine was obtained from rat plasma, urine, and feces using ultra-high-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry. A total of seven metabolites were detected, and the proposed metabolic pathways involved oxidation and glucuronidation. A simple and sensitive ultra-high-performance liquid chromatography-tandem mass spectrometry method was developed for the determination of yuanhuacine in rat plasma. The linear range of yuanhuacine was 1-1000 ng/ml (R

The application of nanoparticles in the diagnosis and treatment of diseases has undergone different developmental stages, but phagocytosis and nonspecific distribution have been the main factors restricting the transformation of nanobased drugs into clinical practice. In the past decade, the design of membrane-coated nanoparticles has gained increasing attention. It is hoped that the combination of the cell membrane's natural biological properties and the functional integration of synthetic nanoparticle systems can compensate for the shortage of traditional nanoparticles. The membrane coating gives the nanoparticles unique biological functions such as immune evasion and targeting capability. However, when the encapsulation of monotypic membranes does not meet the diverse demands of biomedicine, the combination of different cell membranes may offer more possibilities. In this review, the composition, preparation, and advantages of biomimetic nanoparticles coated with hybrid cell membranes are summarized, and the applications of hybrid membrane-coated biomimetic nanoparticles (HM@BNPs) in drug delivery, phototherapy, liquid biopsy, tumor vaccines, immune therapy, and detoxification are reviewed. Finally, the current challenges and opportunities with regard to HM@BNPs are discussed.

Digestive system cancer is the most common cause of cancer death in the world. Although cancer treatment options are increasingly diversified, the mortality rate of malignant cancer of the digestive system remains high. Therefore, it is necessary to explore effective cancer treatment methods. Recently, biomimetic nanoparticle delivery systems based on natural cells that organically integrate the low immunogenicity, high biocompatibility, cancer targeting, and controllable, versatile functionality of smart nanocarrier design with natural cells have been expected to break through the bottleneck of tumor targeted therapy. In this review, we focus on the dynamic changes and complex cellular communications that occur

Indole-3-acetic acid (IAA) and salicylic acid (SA) are two important phytohormones. In this work, for the first time, a ratiometric electrochemical sensor was developed for quantifying IAA and SA simultaneously. A composite of multi wall carbon nanotubes (MWNT) and carbon black (CB) was used to enhance the sensitivity of electrochemical detection. Ferrocene (Fc) was used as the reference molecule to offer a built-in correction to improve the accuracy. A good linearity was constructed between the IIAA/IFc and the concentration of IAA from 25 μM to 1000 μM. The linear equation was y = 0.00159x + 0.124 (R2 = 0.9887). The LOD for IAA was 1.99 μM. Meanwhile, the ISA/IFc gradually increased with increasing concentration of SA. The linear regression equation for SA was y = 0.00107x + 0.34465 (R2 = 0.9488) with the LOD of 3.30 μM. Thus, the as-prepared multifunctional ratiometric electrochemical sensor was successfully applied to detect IAA and SA at the same time. This sensor was also successfully used to detect IAA and SA in the homogenates of soybean seedlings under salt stress, confirming the practical applicability of the sensor. And the obtained results agreed well with those obtained by the ultra performance liquid chromatography-mass spectrometry (UPLC-MS) method.

Detection of signal molecules in living plants is of great relevance for precision farming. In this work, to establish a more effective method for monitoring salicylic acid (SA) in the leaves of living plants, a ratiometric electrochemical sensor was fabricated based on a Cu metal–organic framework (Cu-MOF) and carbon black (CB) composite. The Cu-MOF and CB composite was used to catalyze SA oxidation. Ratiometric oxidation current peak intensities ISA/ICu-MOFs were used as the response signal for SA. ISA/ICu-MOFs linearly enhanced with the increase of SA concentration, together with low limits of detection (12.50 μM). Moreover, our sensor is fabricated on a screen-printed electrode (SPE), which is especially suitable for applying to the flat leaves of plants. Using this sensor, the SA level in the leaves of cucumber seedlings was monitored in vivo under salt stress. The proposed sensor is accurate, reliable and practical. This is the first report for developing a ratiometric electrochemical sensor for detecting SA in living plants. Our work can also provide a strategy for in vivo studies on the leaves of plants.

As well as their ion transportation function, the voltage-dependent potassium channels could act as the cell signal inducer in a variety of pathogenic processes. However, their roles in neurogenesis after stroke insults have not been clearly illustrated. In our preliminary study, the expressions of voltage-dependent potassium channels Kv4.2 was significantly decreased after stroke in cortex, striatum and hippocampus by real-time quantitative PCR assay. To underlie the neuroprotection of Kv4.2 in stroke rehabilitation, recombinant plasmids encoding the cDNAs of mouse Kv4.2 was constructed. Behavioral tests showed that the increased Kv4.2 could be beneficial to the recovery of the sensory, the motor functions and the cognitive deficits after stroke. Temozolomide (TMZ), an inhibitor of neurogenesis, could partially abolish the mentioned protections of Kv4.2. The immunocytochemical staining showed that Kv4.2 could promote the proliferations of neural stem cells and induce the neural stem cells to differentiate into neurons in vitro and in vivo. And Kv4.2 could up-regulate the expressions of ERK1/2, p-ERK1/2, p-STAT3, NGF, p-TrkA, and BDNF, CAMKII and the concentration of intracellular Ca2+. Namely, we concluded that Kv4.2 promoted neurogenesis through ERK1/2/STAT3, NGF/TrkA, Ca2+/CAMKII signal pathways and rescued the ischemic impairments. Kv4.2 might be a potential drug target for ischemic stroke intervention.

Plants operate under a wide range of pH conditions, which makes it difficult to achieve breakthroughs when developing sensors for the in vivo monitoring of bioactive molecules in plants. Herein, we...

A series of trifluoroacetic acid (TFA) modulated metal-organic frameworks UiO-66 catalysts were synthesized for the direct synthesis of dimethyl carbonate (DMC) from CO2 and methanol in this work. Characterization results show that the surface area, pore size, pore volume as well as the amount of missing-linker defects, Lewis acid site, Lewis basic site and hydroxyl of UiO-66-X can be tuned by regulating the amount of TFA modulator. Catalytic activity assessments reveal that TFA modulation enhanced the activity of UiO-66-X. The catalytic activity improvement of the UiO-66-X could be attributed to the increased amount of active sites and the enlargement of porosity originated from TFA modulation. Moreover, a possible reaction mechanism for DMC synthesis from CO2 and methanol over UiO-66-X was proposed based on the in situ FT-IR results.

A series of Ce/SBA-15 catalysts with different degrees of hydrophobicities were prepared via a post-grafting method and used for the direct synthesis of dimethyl carbonate (DMC) from CO2 and methanol. The Ce/SBA-15-6 catalyst exhibited the highest DMC yield of 0.2%, which was close to the equilibrium value under the reaction conditions of 130 °C, 12 h and 12 MPa. The catalysts were characterized via XRD, BET, FT-IR, solid-state 29Si MAS NMR, CA, TEM, XPS and NH3/CO2-TPD; the results indicated that the hydrophobicity of the catalysts facilitated the creation of oxygen vacancies, which could act as Lewis acids to activate methanol. Higher amounts of moderate acid sites led to higher yields of DMC. In addition, the hydrophobicity of the catalysts could also reduce the adsorbed water on their surface and increase the DMC yield while shortening the reaction time.

Salicylic acid (SA) is an important phytohormone. It plays an essential role in regulating many physiological processes of plants. Most of the conventional methods for SA detection are based on in vitro processes. More attention should be paid to develop in vivo methods for SA detection. In this work, Pt nanoflowers and GO were simultaneously electrodeposited and reduced on a Pt wire microelectrode in one step. The Pt nanoflowers/ERGO modified Pt microsensor demonstrated high sensitivity and selectivity for SA. SA could be detected from 100 pM to 1 μM with a detection limit of 48.11 pM. Then this microsensor was used to detect SA in the stem of sunflower seedlings under different salt stresses in vivo. The result showed that with the increasing concentration of salt, SA levels decreased. Our result was also confirmed by UPLC-MS and gene expression analysis. To the best of our knowledge, this is the first report of in vivo detection of SA in plants using the Pt nanoflowers/ERGO modified Pt microelectrode. It is foreseeable that our strategy could pave the way for the in vivo detection of phytohormones in plants.

Methyl jasmonate (MeJA) is an endogenous plant hormone, which plays an important role in agriculture production. A novel probe-free electrochemical immunosensor was fabricated for detecting of MeJA. Fc, carboxylated graphene (COOH-GR) and carboxylated multi-walled carbon nanotubes (COOH-MWNT) composite was formed and used to fabricate screen-printed electrode (SPE). Fc was used as the electronic medium. COOH-GR and COOH-MWNT were used to improve the conductivity and catalytic activity of the sensor and to immobilize the MeJA antibody. Thus, the immunosensor can be used to detect MeJA without external redox probe solution. The designed sensor can detect MeJA in a wide range of 100 fM-100 μM, and its detection limit is as low as 31.26 fM (S/N = 3). The as-prepared probe-free immunosensor is simple, low cost, and does not need redox probe solutions for measurements, which shows great promise for future application in precision agriculture.

A series of Fe–Zr mixed oxides with different Fe content were prepared and used for direct synthesis of dimethyl carbonate (DMC) from CO 2 and methanol. The best catalytic performance was achieved over the Fe 0.7 Zr 0.3 O y catalyst, with DMC yield of 0.44 mmol·gcat −1 and DMC selectivity of 100% under the reaction conditions of 110 °C and 12 MPa. Characterization results of N 2 physisorption, XRD, XPS, TPR and NH 3 /CO 2 -TPD indicated that the Fe–Zr mixed oxides with coexistence structure of hexagonal Fe 2 O 3 and cubic Fe 2 O 3 favored the formation of moderately acidic and basic sites, which then improved the activation of CO 2 and methanol. The DMC yield was shown to be linearly related to the amount of moderately acidic and basic sites.

It has been reported that tungsten disulfide (WS2) can bind single-stranded DNA (ssDNA) with high affinity while it has less affinity toward double stranded DNA (dsDNA). In this work, for the first time, the high affinity between WS2 and ssDNA was used to construct stable sensing interface for ATP detection. A DNA sequence with -SH at one end was first immobilized on Au electrode. WS2 nanosheets were immobilized on the SH-DNA/Au electrode surface due to the strong affinity between WS2 and ssDNA. Then the WS2 nanosheets were used to immobilize ATP binding aptamer (ABA) through the high affinity between WS2 and ssDNA, too. When ATP reacts with the ABA aptamer, duplex will be formed and dissociated from the WS2 nanosheets. On the basis of this, an electrochemical aptasensor for ATP was fabricated. This ATP sensor showed high sensitivity, selectivity and stability due to the unique WS2-ssDNA interactions and the specific aptamer-target recognition. Furthermore, this strategy was generalized to detect Hg2+ using a mercury-specific aptamer (MSO). This strategy can be expected to offer a promising approach for designing high-performance electrochemical aptasensors for a spectrum of targets.

As an important phytohormone, indole-3-acetic acid (IAA) plays an essential role during the whole process of growth and development of plants. In this work, a novel label-free electrochemical impedance immunosensor for IAA determination has been developed. A three-dimensional PAMAM dendrimer was applied to improve greatly the immobilization capacity of antibodies for IAA on a gold electrode. Gold nanoparticles (AuNPs) were used to further improve the sensitivity of the biosensor by forming complexes with anti-IAA antibodies. The developed impedance immunosensor shows ultra-sensitivity, high selectivity and good reliability for IAA detection. The IAA extracted from the stems of sunflowers under different salt stress conditions was successfully detected using the immunosensor. The results are in good agreement with those obtained by UPLC-MS and consistent with published data, thus confirming the practical value of the biosensor. To the best of our knowledge, this is the first electrochemical impedance immunosensor for IAA detection, which provides a promising detection platform for IAA. By replacing antibodies, this strategy can be easily used to detect other phytohormones.

Glucose is not only as a main metabolic material, but also as a signaling molecule during the process of plant growth. In this work, for the first time, we developed an electrochemical microbiosensor suitable for real-time detecting of glucose concentration in plants. The biosensor uses glucose oxidase (GOD) to catalyze the glucose, and uses cellulose acetate (CA) and polycarbonate (PC) to improve the electrochemical selectivity and reduce the dependence of response on ambient oxygen. The linear range of the proposed sensor is wide and the detection limit is lower, which could basically meet the needs of plant testing. The content of glucose in sunflower under salt stress was monitored in real-time successfully, confirming the applicability of the fabricated microbiosensor. This work has a potential to open an innovative way to study the dynamic changes of physiological state of the plants in real-time.

Non-destructive testing of plant organs, tissues, and cells has important implications in studying the immediate physiological status of plants. The portable dynamic ion flux test equipment (PDIFTE) was developed based on Fick’s first law of diffusion and the Nernst equation to achieve the ion flux measurement in pmol cm−2s−1. This equipment integrates micro-imaging, micro-signal processing, automation and control, and biosensor technologies with the original signal acquisition and conditioning module, the motion control module, the macro 3D automatically control platform, micro digital imaging system, electrostatic shielding coating, ion-selective microelectrode, and other components. PDIFTE can detect H+, K+, Na+, Mg2+, Ca2+, Cd2+, Cl−, \( {\text{NO}}_{3}^{ - } \), and \( {\text{NH}}_{4}^{ + } \). This device can be used in the physiological mechanism research of salt-resistant, drought-resistant, cold-tolerant, heavy metal-resistant, and disease-resistant plants. It can also be used in the research on plant nutrition, ion channel-related gene function, and crop resistant breeding screening.

Drought stress is a major environmental constraint for plant growth. Climate-change-driven increases in ambient temperatures resulted in reduced or unevenly distributed rainfalls, leading to increased soil drought. Carex duriuscula C. A. Mey is a typical drought-tolerant sedge, but few reports have examined the mechanisms conferring its tolerant traits. In the present study, the drought responses of C. duriuscula were assessed by quantifying activity of antioxidant enzymes in its leaf and root tissues and evaluating the relative contribution of organic and inorganic osmolyte in plant osmotic adjustment, linking it with the patterns of the ion acquisition by roots. Two levels of stress—mild (MD) and severe (SD) drought treatments—were used, followed by re-watering. Drought stress caused reduction in a relative water content and chlorophyll content of leaves, this was accompanied by an increase in the hydrogen peroxide (H2O2) and superoxide (O2−) contents in leaves and roots. Under MD stress, the activities of catalase (CAT), peroxidase (POD), and glutathione peroxidase (GPX) increased in leaves, whereas, in roots, only CAT and POD activities increased. SD stress led to an increase in the activities of CAT, POD, superoxide dismutase (SOD), and GPX in both tissues. The levels of proline, soluble sugars, and soluble proteins in the leaves also increased. Under both MD and SD stress conditions, C. duriuscula increased K+, Na+, and Cl− uptake by plant roots, which resulted in an increased K+, Na+, and Cl− concentrations in leaves and roots. This reliance on inorganic osmolytes enables a cost-efficient osmotic adjustment in C. duriuscula. Overall, this study revealed that C. duriuscula was able to survive arid environments due to an efficient operation of its ROS-scavenging systems and osmotic adjustment mechanisms.

In vivo detecting of plants signal molecules is of great importance for the precision farming, crop management and plant phenotyping. In this work, for in vivo detecting indole-3-acetic acid (IAA), one of phytohormones, fine stainless steel (SS) wire was used as electrode material. Highly ordered nanopores, popcorn-like Au nanostructures, Pt nanoparticles and reduced graphene oxide (ERGO) nanocomposite films, and polymerized ST film (PST) were fabricated on the SS microelectrode in turn for improving the detection effect. Using the as-prepared SS microelectrode as working electrode, two untreated SS wires as reference electrode and counter electrode respectively, a disposable electrochemical microsensor for IAA were developed. The microsensor exhibited excellent selectivity and high sensitivity with low detection limit (LOD) of 43 pg mL−1. The limit of quantity (LOQ) is 143 pg mL−1. The RSD was 7% for 12 different PST/Pt-ERGO/Au/a-SS microsensors in presence of 100 µg mL−1 IAA. Using this microsensor, IAA of the stem of soybean seedlings was detected in vivo under salt stress. Our result was also confirmed by ultra-performance liquid chromatography-mass spectrum (UPLC-MS). This is the first report for the in vivo detection of IAA in plants using SS-based electrochemical microsensor. Our sensor provides an excellent sensing platform for detecting IAA in plants in vivo.

The construction of p–n junctions with built-in electric field effect between two photocatalytic semiconductors is an efficient strategy to separate photogenerated carriers and enhances photocatalytic activity. However the effect is limited because the built-in electric field can be saturated because of the charge accumulation during the photocatalysis process. In this work, we demonstrate that inserting a layer of zero-bandgap graphene at the interface between p-type NiO and n-type TiO 2 can further enhance the separation of photogenerated carriers by building double-shelled NiO/rGO/TiO 2 heterostructured coaxial nanocables This double-shell nanostructure is proved possessing a remarkably high photocatalytic activity through water splitting experiments and photoelectrochemical measurements. The main mechanism for enhancement of photocatalytic activity is that zero-bandgap rGO can increased the barrier height by lowering the Fermi level of the NiO nanofiber core and increasing the Fermi level of the TiO 2 nanowire shell, and enhance the strength of built-in electron field. Furthermore, the design of NiO/rGO/TiO 2 heterostructured coaxial nanocables can ensure that the UV light can be absorbed by the TiO 2 at the outer shell, whereas visible light can reach the NiO inner core, thus leading to an efficient use of the white light spectrum. This heterostructured coaxial nanocable is a promising candidate for applications in environmental and energy fields because of its facile and easily scalable synthesis combined to its superior broad-spectrum photocatalytic activity.

Photoelectrocatalysis is an efficient approach for the degradation of organic pollutants as well as for water splitting. However, an external power source supplying a direct current (DC) is essential to enhance the separation of photo-induced carriers. In this paper, a fully-functional photoelectrocatalysis device was constructed by connecting single crystalline TiO2 nanowires assembled on graphite microfibers (TiO2 nanowire/graphite fiber, TNGF) to a wind-driven triboelectric nanogenerator (WDTENG). The excellent photocatalytic and photoelectrocatalytic properties of TNGF originate from the ability of graphite fibers to transport rapidly the charge carriers, the high photocatalytic activity of TiO2 nanowires and the photo-induced carrier separation enhancement created by the zero band gap of graphite. When this system is used for hydrogen generation via photoelectrocatalytic water splitting, the hydrogen evolution of the TNGF is significantly increased under assistance of the WDTENG. Photoelectrochemical analysis demonstrates that the separation and recombination of photo-induced charge carriers in the 7TNGF composite is dependent on the applied voltage bias. Thus, the wind driven generator

Semiconductor nanostructures with photocatalytic activity have many potential applications including remediation of environmental pollutants and photocatalytic hydrogen evolution. An effective way of promoting photocatalytic activity is by creating heterogeneous photocatalysts. In this paper, a hybrid nanostructured photocatalyst with desired three-dimensional (3D) nanoarchitecture by assembling Sn3O4 nanosheets on N-doped TiO2 nanotubes has been constructed with enhanced broad spectrum photocatalytic properties, which can harness UV and visible light to decompose organic contaminants in aqueous solutions and split water to hydrogen. Photocatalytic tests showed that the Sn3O4/N-TiO2 hierarchical hybrid nanostructures possessed a much higher degradation rate of methyl orange and hydrogen evolution rate than that of the unmodified TiO2 nanotubes, N-TiO2 nanotubes, Sn3O4 nanosheets and Sn3O4/TiO2 hybrid nanostructures. The mechanism related to the enhancement of the photocatalytic activity was discussed. Deposition of Sn3O4 nanosheets onto N-TiO2 nanotubes resulted in a dramatic increase in light-induced generation of hydroxyl radicals, superoxides and singlet oxygen, and the production of holes and electrons. This work is the first instance of combining Sn3O4 with N-TiO2, the Sn3O4/N-TiO2 hierarchical hybrid nanostructures show good photocatalytic performance. This study is potentially applicable to a range of 3D hybrid nanostructures with promising applications in photocatalysis and relevant areas.

Complex logic gate operations using organic microwires as signal transducers based on electrogenerated chemiluminescence (ECL) intensity as the optical readout signal have been developed by taking advantage of the unique ECL reaction between organic semiconductor 9,10-bis(phenylethynyl)anthracene (BPEA) microwires and small molecules. The BPEA microwires, prepared on cleaned-ITO substrate using a simple physical vapor transport (PVT) method, were subsequently used for construction of the ECL sensors. The developed sensor exhibits high ECL efficiency and excellent stability in the presence of co-reactant tripropylamine. Based on the remarkable detection performance of BPEA MWs/TPrA system, the sensors manifested high sensitive ECL response in a wide linear range with low detection limit for the detection of dopamine, proline or methylene blue, which behaves on the basis of molecule-responsive ECL properties based on different ECL reaction mechanisms. Inspired by this, these sensing systems can be utilized to design OR, XOR and INHIBIT logic gates, which would be used for the determination of dopamine, proline and ethylene blue via logic outputs. Importantly, the individual logic gates can be easily brought together through three-input operations to function as integrated logic gates.

A sensitive electrogenerated chemiluminescence (ECL) sensor with an organic semiconductor as active material for detecting trace amounts of molecules has been highly desired. However, the crystal structure responses of the ECL properties of the organic semiconductor materials, that is, structure-property relationship, is not clear, which limits the development of the sensitive ECL sensors. Herein, for the first time, we reported a novel concept for molecular-stacking-arrangement-dependent electrogenerated chemiluminescence properties of organic semiconductor rubrene microstructures. The rubrene 1D microwires and 2D hexagonal plates with different polymorphs (triclinic and monoclinic) were controllably constructed with the reprecipitation method. The supersaturation of the rubrene molecules plays an important role in the thermodynamically and kinetically dominated process of growth, which affects not only the polymorphs but also the morphology of the obtained microstructures. These microstructures show good optoelectronic properties, which are used as active ECL materials for the construction of ECL sensors. The ECL sensors exhibited distinct electrogenerated chemiluminescence properties, probably related to different inherent crystal-structure-dependent triplet-triplet annihilation rate and charge-transfer rate. The sensors manifested electrogenerated chemiluminescence responses in broad linear range for the monitoring of creatinine molecules.

To study the influences of indoor and outdoor climate on thermal adaptation, a field study was conducted in classrooms and offices in winter and spring. The thermal environment parameters in the classrooms and offices were tested during the survey, while the subjects were interviewed on their thermal responses. The results showed that human thermal sensations were related to both indoor and outdoor climates. The neutral temperatures were not the same under different indoor temperature conditions in winter. The indoor microclimates had influences on human adaptability; the thermal neutral temperature was close to the indoor mean air temperature in thermal comfort environments. However, people felt hot when the indoor temperature was high and beyond the comfort zone in winter. Because the winter is long and outdoor temperature is low in Harbin, people have adapted to the cold environment. The indoor temperature should be kept at the lower limit of the comfort range in winter to keep human comfort and save energy. The neutral temperatures were different in winter and spring which proved that the outdoor climate influenced human adaptation. The indoor temperature in winter is suggested lower than that in spring, which is a comfortable and energy efficient regulation strategy. According to the regulation strategy, about 9.6% energy for centralized heating system can be saved.

Since rhesus monkeys of Chinese origin have gained greater utilization in recent years, it is urgent to investigate the major histocompatibility complex (MHC) immunogenetics of Chinese rhesus macaques. In this study, we identified 81 Mamu-B sequences using complementary DNA cloning and sequencing on a cohort of 58 rhesus monkeys derived from three local populations of China. Twenty of these Mamu-B alleles are novel and four of them represent new lineages. Although more alleles are shared among different populations than Mamu-A locus, the Mamu-B allelic repertoires found in these three populations of Chinese macaques are largely independent, which underscores the MHC polymorphism among different populations of Chinese rhesus macaques. Our results are an important addition to the limited MHC immunogenetic information available for rhesus macaques of Chinese origin.

It has been reported that tungsten disulfide (WS

The demand for a highly sensitive and selective glucose biosensor which can be used for implantable or on-time monitoring is constantly increasing. In this work, TiO2 nanorods were synthesized in situ on the surface of graphite microfibers to yield TiO2 nanorod/graphite microfiber hybrid electrodes. The TiO2 nanorods not only retain the high activity of the immobilized glucose molecule, but also promote the direct electron transfer process on the electrode surface. As a working electrode in an electrochemical glucose biosensor in a flowing system, the microfiber hybrid electrodes exhibit high sensitivity, selectivity and stability. Due to its simplicity, low cost, high stability, and unique morphology, the TiO2 nanorod/graphite microfiber hybrid electrode is expected to be an excellent candidate for an implantable biosensor or for in situ flow monitoring.

Endothelial NOS (NOS3) has a potential role in the prevention of neuronal injury in hypoxic-ischemic encephalopathy (HIE). Thus, we aimed to explore the association between NOS3 gene polymorphisms and HIE susceptibility and symptoms in a Chinese Han population. Three single nucleotide polymorphisms (SNPs) in the NOS3 gene, rs1800783, rs1800779, and rs2070744, were detected in 226 children with HIE and 212 healthy children in a Chinese Han population. Apgar scores and magnetic resonance image scans were used to estimate the symptoms and brain damage. The association analyses were conducted by using SNPStats and SPSS 18.0 software. The genotype and allele distributions of rs1800779 and rs1799983 displayed no significant differences between the patients and the controls, while the rs2070744 allele distribution was significantly different (correctedP=0.009). For clinical characteristics, the rs2070744 genotype distribution was significantly different in patients with different Apgar scores (≤5, TT/TC/CC = 6/7/5; 6~7, TT/TC/CC = 17/0/0; 8~9, TT/TC/CC = 6/2/0; 10, TT/TC/CC = 7/1/0; correctedP=0.006) in the 1001 to 1449 g birth weight subgroup. The haplotype test did not show any associations with the risk and clinical characteristics of HIE. The results suggest that NOS3 gene SNP rs2070744 was significantly associated with HIE susceptibility and symptom expression in Chinese Han population.

α-Actinin has been shown to be capable of interacting with some special membrane phospholipids directly, which is important for its function. In this study, hybrid bilayer membranes composed of negatively charged lipids are constructed on the surface plasmon resonance gold substrate and on the gold electrode, respectively, and the interaction between α-actinin and negatively charged lipids membrane is investigated by surface plasmon resonance, cyclic voltammetry and electrochemical impedance spectroscopy methods. α-Actinin is proved to be able to interact with the negatively charged lipids membrane directly. It can also insert at least partly into the membrane or lead to some defect or lesion in the membrane, which increase the permeability of the membrane. This study would bring some insight on the interaction between the α-actinin and the cell membranes in vivo.

Bioactive ultrathin films with the incorporation of amino-terminated G4 PAMAM dendrimers have been prepared via layer-by-layer self-assembly methods on a gold electrode and used for the DNA hybridization analysis. Surface plasmon resonance (SPR), X-ray photoelectron spectroscopy (XPS), and electrochemical impedance spectroscopy (EIS) are used to characterize the successful construction of the multicomponent film on the gold substrate. The dendrimer-modified surfaces improve the immobilization capacity of the probe DNA greatly, compared to the AET (2-aminoethanethiol) SAM sensor surfaces without dendrimer molecules. DNA hybridization analysis is monitored by EIS. The dendrimer-based electrochemical impedance DNA biosensor shows high sensitivity and selectivity for DNA hybridization assay. The multicomponent films also display a high stability during repeated regeneration and hybridization cycles.

Polarized ferroelectric crystal lithium niobate wafers with different cuts are selected to offer differently charged surfaces. By induction of the mesenchymal stem cells differentiation into osteoblasts on different charged surfaces, the specific osteogenic-associated markers are assessed and the results illustrate that the positively charged wafer surface enhances rBMMSCs osteogenic differentiation.

Tibetan macaques (Macaca thibetana), stump-tailed macaques (M. arctoides), Assamese macaques (M. assamensis), and northern pig-tailed macaques (M. leonina) are four major species of Macaca in China. In order to effectively use these species in biomedical research, thorough investigations of their MHC immunogenetics are required. In this study, we identified MHC class I sequences using cDNA cloning and sequencing on a cohort of six M. thibetana, three M. arctoides, three M. assamensis, and three M. leonina derived from Sichuan and Yunnan provinces of China. Eighty new alleles were identified, including 26 MHC-A alleles, 46 MHC-B alleles, and 8 MHC-I alleles. Among them, Math-A1*126:01, Math-B*190:01, Math-B*191:01, Math-B*192:01, Maar-A1*127:01, Maar-A1*129:01, and Maas-A1*128:01 represent lineages that had not been reported earlier in Macaca. Phylogenetic analyses show that no obvious separation of lineages among these species of Macaca. This study provides important information about the MHC immunogenetics for the four major species of Chinese macaques and adds value to these species as model organisms in biomedical research.