Design of a prodrug photocage for cancer cells detection and anticancer drug release

Developing probes for simultaneous diagnosis and killing of cancer cells is crucial, yet challenging. This article presents the design and synthesis of a novel Rhodamine B fluorescence probe. The design strategy involves utilizing an anticancer drug (Melphalan) to bind with a fluorescent group (HRhod-OH), forming HRhod-MeL, which is non-fluorescent. However, when exposed to the high levels of reactive oxygen species (ROS) of cancer cells, HRhod-MeL transforms into a red-emitting Photocage (Rhod-MeL), and selectively accumulates in the mitochondria of cancer cells, where, when activated with green light (556 nm), anti-cancer drugs released. The Photocage improve the efficacy of anti-cancer drugs and enables the precise diagnosis and killing of cancer cells. Therefore, the prepared Photocage can detect cancer cells and release anticancer drugs in situ, which provides a new method for the development of prodrugs.

Visual monitoring of biocatalytic processes using small molecular fluorescent probes: strategies-mechanisms-applications

Real-time monitoring of biocatalytic-based processes is significantly improved and simplified when they can be visualized. Visual monitoring can be achieved by integrating a fluorescent unit with the biocatalyst. Herein, we outline the design strategies of fluorescent probes for monitoring biocatalysis: (1) probes for monitoring biocatalytic transfer: γ-glutamine is linked to the fluorophore as both a recognition group and for intramolecular charge transfer (ICT) inhibition; the probe is initially in an off state and is activated via the transfer of the γ-glutamine group and the release of the free amino group, which results in restoration of the "Donor-π-Acceptor" (D-π-A) system and fluorescence recovery. (2) Probes for monitoring biocatalytic oxidation: a propylamine is connected to the fluorophore as a recognition group, which cages the hydroxyl group, leading to the inhibition of ICT; propylamine is oxidized and subsequently β-elimination occurs, resulting in exposure of the hydroxyl group and fluorescence recovery. (3) Probes for monitoring biocatalytic reduction: a nitro group attached to a fluorophore as a fluorescence quenching group, this is converted to an amino group by catalytic reduction, resulting in fluorescence recovery. (4) Probes for monitoring biocatalytic hydrolysis: β-D-galactopyranoside or phosphate acts as a recognition group attached to hydroxyl groups of the fluorophore; the subsequent biocatalytic hydrolysis reaction releases the hydroxyl group resulting in fluorescence recovery. Following these 4 mechanisms, fluorophores including cyanine, coumarin, rhodamine, and Nile-red, have been used to develop systems for monitoring biocatalytic reactions. We anticipate that these strategies will result in systems able to rapidly diagnose and facilitate the treatment of serious diseases.

Effect of Rhei Radix et Rhizoma and Eupolyphaga Steleophaga on liver protection mechanism based on pharmacokinetics and metabonomics

Objective

Based on metabonomics technology of high-performance liquid chromatography-mass spectrometry (HPLC-MS/MS) and hydrogen nuclear magnetic resonance spectroscopy (1H NMR), the pharmacokinetic characteristics and therapeutic mechanism of Rhei Radix et Rhizoma (RhRR, Dahuang in Chinese), Eupolyphaga Steleophaga (EuS, Tubiechong in Chinese) combined with RhRR acting on acute liver injury were explored.

Methods

Models of acute liver injury were established, and the pharmacokinetic methods of five components of RhRR-EuS in rats were found by HPLC-MS/MS. The liver tissues of different groups of mice were analyzed by 1H NMR spectroscopy combined with multivariate statistical analysis to investigate the metabolomics of RhRR-EuS and RhRR.

Results

Pharmacokinetic results showed there were different levels of bimodal phenomenon in different groups, and the absorption of free anthraquinone in RhRR increased after compatibility with EuS. In addition, the pathological state of acute liver injury in rats can selectively promote the absorption of emodin, chrysophanol, physcion and aloe emodin. Through 15 differential metabolites in the liver tissue of acute liver injury mice, it was revealed that RhRR-EuS and RhRR could protect the liver injury by regulating the metabolism of glutamine and glutamic acid, alanine, aspartic acid and glutamic acid, and phosphoinositide. However, the regulation of RhRR was weaker than that of RhRR-EuS.

Conclusion

For the first time, we studied the pharmacokinetics and metabolomics differences of RhRR-EuS and RhRR in rats and mice with acute liver injury, in order to provide theoretical reference for clinical treatment of liver disease by DHZCP.

Study on pharmacokinetics and tissue distribution of Polygonatum sibiricum polysaccharide in rats by fluorescence labeling

To study the pharmacokinetics and tissue distribution characteristics of Polygonatum sibiricum (P. sibiricum) polysaccharide administered orally and intravenously in rats, the latest quantitative analysis method was established where P. sibiricum polysaccharide was labeled with fluorescein isothiocyanate (FITC) in plasma and tissues. Quantitative analysis method of P. sibiricum polysaccharide in rat plasma and tissues was established by fluorescence spectrophotometry with FITC as a highly sensitive fluorescent molecular probe. The results showed that P. sibiricum polysaccharide was successfully labeled with FITC, and the degree of substitution was 0.55 %. Pharmacokinetic characteristics showed that oral administration (ig) and intravenous injection (iv) were consistent with the characteristics of two-compartment model. PRP-TYR-FITC administered orally was poorly absorbed in rats with low bioavailability. After a single ig and iv administration in rats for 8 h, P. sibiricum polysaccharide can be distributed in most tissues. The analysis results showed that P. sibiricum polysaccharide was distributed mostly in lung, kidney and liver for both routes of administration. When taking orally, the distribution pattern was: lung > liver > kidney > small intestine > stomach > heart > spleen > brain. When taking intravenously, the distribution pattern was: liver > lung > kidney > small intestine > heart > stomach > spleen > brain. Fluorescence labeling of P. sibiricum polysaccharide by FITC was successfully realized. This method was proved to be suitable for the study of pharmacokinetics and tissue distribution of P. sibiricum polysaccharide in rats. The above research lays foundation for further elucidating the clinical pharmacological mechanism of polysaccharide in P. sibiricum.

Determination of Polysaccharides Composition in Polygonatum sibiricum and Polygonatum odoratum by HPLC-FLD with Pre-column Derivatization

A high-performance liquid chromatography-fluorescence detection (HPLC-FLD) method was established for the determination of seven monosaccharides in Polygonatum sibiricum and Polygonatum odoratum. The polysaccharides were de-esterified, extracted, hydrolyzed and derivatized with p-aminobenzoic acid (PABA) to obtain fluorescently labeled monosaccharide compounds, which were finally detected by HPLC-FLD. Inertsil ODS-3, C18 chromatographic column (250 mm × 4.6 mm, 5 μm) was used for chromatography. The excitation wavelength (E_x) was 313 nm, and the emission wavelength (E_m) was 358 nm. Ethyl acetate extraction reduced the peaks of chromatogram and improved the detection sensitivity than other agents. The established method had high sensitivity, strong specificity, good linear relationship and recovery efficiency. The results showed that the roots and fibrous roots of Polygonatum sibiricum and Polygonatum odoratum contained these seven monosaccharides, and the highest monosaccharide content was mannose. The method of PABA-HPLC-FLD for determination of monosaccharide content in Polygonatum sibiricum and Polygonatum odoratum was sensitive and accurate. The method established in this work provides a feasible analytical tool for the study of polysaccharides, and the findings on polysaccharides from Polygonatum sibiricum and Polygonatum odoratum can provide guidance for the natural medicine industry.

Simultaneous Determination of Six Alkaloids in Rat Plasma by SPE-HPLC-MS/MS and Their Pharmacokinetics after Oral Administration of Radix aconiti Preparata Extract

Simultaneous determination of the content of six alkaloids (aconitine, hypoaconitine, mesaconitine, benzoylaconine, benzoylhypaconine, and benzoylmesaconine) in rat plasma is enabled by HPLC-MS/MS combined with microsolid phase extraction (micro-SPE). To study its pharmacokinetics in rat plasma, the extracted plasma sample was passed through a C18 extraction column and eluted with acetonitrile. The six alkaloids in the Radix aconiti Preparata extract can be completely separated as peaks with good shape. The six components in the plasma sample showed a good linear relationship within their respective linear ranges (R ² > 0.997). The analysis of the six alkaloids can be completed within 20 min. This method has high intraday and interday precision, and the room temperature stability and freeze-thaw stability are good. The matrix effect of the plasma samples is between 86.4 and 114%. The metabolism of the six Aconitum alkaloids in plasma is analyzed using a two-compartment model, which is characterized by fast absorption, slow elimination, and good linear fit, R ² > 0.99. The peak time (T _max) for aconitine, hypaconitine, and neoaconitine ranged from 29.95 to 42.07 min, while the peak time (T _max) for benzoaconitine, benzohypaconitine, and benzoxinaconitine ranged from 42.88 to 73.08 min. With the increased dosage, the bioavailability of Aconitum alkaloids decreased gradually. The method for the determination of Aconitum alkaloids in rat plasma by high performance liquid chromatography-tandem mass spectrometry is sensitive and accurate, which is suitable for rat plasma analysis. The results provide a scientific basis for metabolic study of Aconitum alkaloids in vivo, and pave the way for clinical use of Aconitum medicinal materials and extracts.

Metabolomics study of polysaccharide extracts from Polygonatum sibiricum in mice based on 1 H NMR technology

BACKGROUND

Polygonatum sibiricum Liliaceae perennial herb, as a commonly used medicine and food homologous plant, has been widely used in clinical practice of Chinese medicine since ancient times, with a history of 2000 years. As the main active ingredient, P. sibiricum polysaccharides have important pharmacological effects in blood sugar reduction and antitumor, antioxidant and liver protection.

RESULTS

Mouse models of P. sibiricum polysaccharides were used in combination with ¹ H NMR to investigate the metabolic regulation mechanism in mouse tissue and blood. The metabolite maps of the control group and the drug group in the liver had significant changes. The main differential metabolites were glucose 6-phosphate, inositol, lactose, glutamylglycine, galactose, rhamnose, cis-aconitic acid and histidine, indicating that there was definite correlation between the metabolic detection based on ¹ H NMR and the metabolic characteristics of P. sibiricum. The common differential metabolites obtained by overall metabolism analysis were 3-hydroxybutyric acid, d-ribose, adenosine phosphate, inositol, fructose 6-phosphate, histidine, aspartic acid and cis-aconitic acid.

CONCLUSIONS

This work forms the basis for identification of metabolic states combined with metabolic pathways, which could be used as diagnostic and prognostic indicators, providing therapeutic targets for new diseases. © 2020 Society of Chemical Industry.

MiR-15a-3p suppresses the growth and metastasis of ovarian cancer cell by targeting Twist1

OBJECTIVE

To investigate the roles of miR-15a-3p in ovarian cancer cell growth and metastasis.

PATIENTS AND METHODS

A key role of miR-15a-3p was identified via gene profiling and bioinformatics analysis. The impact of miR-15a-3p on ovarian cancer cell growth, migration and invasion was measured by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT), wound-healing and transwell invasion assays. Bioinformatics and luciferase reporter assays were applied to identify that twist family BHLH transcription factor 1 (Twist1) was the target gene of miR-15a-3p. The miR-15a-3p level and the expression of Twist1 were detected using quantitative Real-time polymerase chain reaction (qRT-PCR) assay. The expressions of N-cadherin and E-cadherin were measured by immunofluorescence staining. Small interfering RNA targeting Twist1 and pCDNA3.1 containing Twist1 were applied to decrease and increase the expression of Twist1, respectively.

RESULTS

miR-15a-3p was markedly down-regulated in ovarian cancer. Exogenous up-regulation of miR-15a-3p inhibited the growth, colony formation, migration and invasion of ovarian cancer cell in vitro. Furthermore, a xenograft model indicated that miR-15a-3p inhibited tumour growth and the metastatic potential of ovarian cancer cell in vivo. We found that Twist1 was the direct target of miR-15a-3p in ovarian cancer and that its expression was negatively correlated with the level of miR-15a-3p in ovarian cancer tissues. Up-regulation of miR-15a-3p rescued the inhibitory impact of miR-15a-3p on ovarian cancer cell growth, migration and invasion. Finally, down-regulation of Twist1 mimicked the suppressive effects of miR-15a-3p on ovarian cancer cell.

CONCLUSIONS

We demonstrated that miR-15a-3p is down-regulated in ovarian cancer. Up-regulation of miR-15a-3p restrains the growth and metastasis of ovarian cancer cell by regulating Twist1.

Study of miR-26a inhibiting epithelial-mesenchymal transition and invasion of Tu686 cell line through SMAD1

OBJECTIVE

This study aims to investigate the effect of miR-26a on the epithelial-mesenchymal transition (EMT) and invasion of Tu686 cell line through SMAD1.

MATERIALS AND METHODS

Tu686 Squamous cell carcinoma of head and neck (SCCHN) cell strains were divided into the miR-26a group, miR-NC group, co-transfection group and blank control group. Among them, the miR-26a group only transfected miR-26a mimics, the miR-NC group only transfected miR-26a negative control, the co-transfection group transfected miR-26a mimics and pcDNA3.1-SMAD1 plasmid. The qRT-PCR method was used for the detection of the expressions of miR-26a and SMAD1 in each group of cells, transwell assay for the detection of the invasion ability of each group of cells and Western blot for detecting the expression level of SMAD1 and the expressions of EMT-related proteins E-cadherin and N-cadherin.

RESULTS

The relative expression of miR-26a in the miR-26a group was significantly higher than that in the miR-NC group and blank control group, and the relative expression in the co-transfection group was significantly higher than that in the miR-NC and blank control groups. The relative expression of SMAD1 in the miR-26a group was significantly lower than that in the miR-NC and blank control groups, and the relative expression in the co-transfection group was lower than that in the miR-NC and blank control groups, and higher than that in the miR-26a group (all p<0.05). There was no significant difference between the miR-NC group and the blank control group (p>0.05).

CONCLUSIONS

miR-26a may reduce the expression level of SMAD1, affect the expression of EMT-related proteins, inhibit the EMT function of Tu686 cells of squamous cell carcinoma of head and neck, and inhibit the invasion of them.

Evaluation of Pantoea eucalypti FBS135 for pine (Pinus massoniana) growth promotion and its genome analysis

AIMS

Pinus massoniana is one of the most widely distributed forest plants in China. In this study, we isolated a bacterial endophyte (designated FBS135) from apical buds and needles of P. massoniana. Investigations were performed to understand the effects of the strain on pine growth, its genomic features and the functions of the plasmids it carries.

METHODS AND RESULTS

Based on its morphological features and 16S rRNA sequence, strain FBS135 was primarily identified as Pantoea eucalypti. We found that FBS135 not only promoted the growth of P. massoniana seedlings, but also significantly increased the survival rate of pine seedlings. The whole genome of FBS135 was sequenced, which revealed that the bacterium carries one chromosome and four plasmids. Its chromosome is 4 023 751 bp in size and contains dozens of genes involved in plant symbiosis. Curing one of the four plasmids, pPant1, resulted in a decrease in the size of the FBS135 colonies and the loss of the ability to synthesize yellow pigment, indicating that this plasmid may be very important for FBS135.

CONCLUSIONS

Pantoea eucalypti FBS135 has a genomic basis to be implicated in plant-associated lifestyle and was established to have the capability to promote pine growth.

SIGNIFICANCE AND IMPACT OF THE STUDY

To the best of our knowledge, this is the first report that such a bacterial species, P. eucalypti, was isolated from pine trees and evidenced to have pine beneficial activities. Our results elucidate the ecological effects of endophytes on forest plants as well as endophyte-plant interaction mechanisms.

Efficient, accurate and comprehensive evaluation of polysaccharides from Fritillaria and their inhibitory responses to mouse inflammation

Fritillaria is a perennial herb with bulbs with multiple medicinal usages. Here, we optimized extraction and hydrolysis methods for different species and origins of Fritillaria to study their anti-inflammatory activities. Using ultrasound-assisted hot water extraction after hydrolysis by hydrochloric acid and trifluoroacetate (TFA), monosaccharide derived from 1-phenyl-3-methyl-5-pyrazolone (PMP) was separated by using HPLC. The optimal conditions for hot water extraction were found via single factor analysis and orthogonal experiments. The PMP derivatization HPLC method could accurately determine the Mannose (Man), Glucose (Glu), Galactose (Gal), Xylose (Xyl), and Fucose (Fuc) content values in Fritillaria. This pre-column derivatization method is simple and rapid, providing less variation, high sensitivity and good reproducibility for saccharide separation. To study Fritillaria's anti-inflammatory effects in a mouse swelling model, HE-staining was performed to observe morphological changes in liver and kidney samples. Fritillaria's active ingredients could significantly inhibit mouse ear swelling induced by xylene and inhibit toe swelling induced by egg white. They mainly inhibited the secretion of inflammatory cytokines inside the body and maintained the dynamic balance between pro-inflammatory and anti-inflammatory factors in the body. According to histopathological analysis, Fritillaria had good anti-inflammatory activity against LPS-induced inflammation, reducing the expression of inflammatory cytokines.

Impact of P inputs on source-sink P dynamics of sediment along an agricultural ditch network

Phosphorus (P) loss from intensive dairy farms is a pressure on water quality in agricultural catchments. At farm scale, P sources can enter in-field drains and open ditches, resulting in transfer along ditch networks and delivery into nearby streams. Open ditches could be a potential location for P mitigation if the right location was identified, depending on P sources entering the ditch and the source-sink dynamics at the sediment-water interface. The objective of this study was to identify the right location along a ditch to mitigate P losses on an intensive dairy farm. High spatial resolution grab samples for water quality, along with sediment and bankside samples, were collected along an open ditch network to characterise the P dynamics within the ditch. Phosphorus inputs to the ditch adversely affected water quality, and a step change in P concentrations (increase in mean dissolved reactive phosphorus (DRP) from 0.054 to 0.228 mg L^-1) midway along the section of the ditch sampled, signalled the influence of a point source entering the ditch. Phosphorus inputs altered sediment P sorption properties as P accumulated along the length of the ditch. Accumulation of bankside and sediment labile extractable P, Mehlich 3 P (M3P) (from 13 to 97 mg kg^-1) resulted in a decrease in P binding energies (k) to < 1 L mg^-1 at downstream points and raised the equilibrium P concentrations (EPC₀) from 0.07 to 4.61 mg L^-1 along the ditch. The increase in EPC₀ was in line with increasing dissolved and total P in water, demonstrating the role of sediment downstream in this ditch as a secondary source of P to water. Implementation of intervention measures are needed to both mitigate P loss and remediate sediment to restore the sink properties. In-ditch measures need to account for a physicochemical lag time before improvements in water quality will be observed.

Tensorial Modulation of Electrokinetic Streaming Potentials on Air and Liquid Filled Surfaces

Textured surfaces, comprised of grooves filled with air, e.g., air-filled surfaces (AFS), or with liquid, e.g., liquid-filled surfaces (LFS), significantly influence fluid flows and the related electrokinetic streaming potential (V_s). Here, electroosmotic mobility related tensorial effects on the V_s were experimentally investigated. A significant modulation of the V_s, as high as 100%, due to transverse pressure gradients, was demonstrated. The study yields insights into understanding geometrical effects in electrolyte flows with implications to the establishment of local electric fields, energy generation, and biological separations.

Signal Sensitivity Enhancement of High-Spatial-Resolution MR Imaging with a Concatenated Cylindrical Parametric RF-Resonator

Phased array MRI coils can increase sensitivity of superficial tissues owing to their proximity to the detection region. Deep-lying tissues, on the other hand, do not benefit to the same degree. Here we investigate the use of a localized cylindrically symmetric quadruple frequency resonator concatenated with a double frequency resonator to increase the longitudinal field-of-view (FOV) without compromising the spatial-resolution and detection sensitivity. These concatenated array coils work on the principle of a parametric amplification to provide wireless amplification of the locally detected NMR signal prior to inductively coupling the coil to an external pick-up loop with connection to the system receiver. When both the detectors are activated together, the effective range of both overlay to create a larger FOV enabling better identification of detectable regions. Furthermore, the in-vivo test of the concatenated detector provides a worst-case 5-fold SNR gain in regions separated from the cylindrical surface larger than its own diameter. This proposed approach of concatenated detector realization can be individually activated and manipulated to enlarge the sensitivity-enhanced region without sacrificing their individual performance. Compared to double frequency detectors, quadruple frequency detectors offer more flexibility in the choice of detector dimension, enabling multi-element concatenation over an extended FOV.

A rapid, accurate and sensitive method for determination of monosaccharides in different varieties of Osmanthus fragrans Lour by pre-column derivatization with HPLC-MS/MS

A specific HPLC-MS/MS (High-Performance Liquid Chromatography with tandem Mass Spectrometry) method was developed and validated for simultaneous determination of several monosaccharides in three kinds Osmanthus fragrans Lour. After extraction, separation, protein removal, pigment removal and hydrolysis, monosaccharides was finally obtained from Osmanthus fragrans Lour. Positive ion mode detection and Multiple Reaction Monitoring (MRM) mode were used for quantitative analysis by PMP pre-column derivatization and Electrospray Ionization (ESI). Analysis and content determination of 6 monosaccharide components in 3 kinds of Osmanthus fragrans Lour. The HPLC separation was achieved on a Shim-pack VP-ODS6022748 (150 L × 2.0) with gradient elution at a flow rate of 0.2 ml/min in a run time of 40 min, and the mobile phase was acetonitrile-5 mmol/L ammonium acetate. PMP derivatization in HPLC-MS/MS can accurately measure Osmanthus fragrans Lour. mannose (Man), ribose (Rib), rhamnose (Rha), galacturonic acid (Gal UA), glucose (Glu), galactose (Gal), xylose (Xyl), fucose (Fuc). The results showed that HPLC-MS/MS pre-column derivatization method was simple and rapid, with small measurement error, but high sensitivity and good repeatability. The analysis of monosaccharide components in polysaccharide components has important practical significance.

Hollow-Core-Photonic-Crystal-Fiber-Based Miniaturized Sensor for the Detection of Aggregation-Induced-Emission Molecules

A miniature sensor for detection of aggregation-induced-emission (AIE) molecules is proposed in this work. The sensing head is fabricated by use of hollow-core photonic crystal fiber with a core diameter of about 4.8 μm. The cladding holes are sealed with a fusion splicing technique, and the central hole remains open to allow the filtration of solution with AIE molecules. When the solution is excited by an ultraviolet lamp, the fluorescence is received by a fiber-optic spectrometer. The fluorescence intensity is associated with the concentration of AIE molecules and the infiltrated-core length. In the whole process of the experiments, the output-peak wavelength is stable, which indicates that the existing forms of AIE particles are stable, and the fluorescence reabsorption can be neglected. The experimental results obtained are in accordance with traditional microplate-spectrophotometer methods. The most exciting result is that the amount of sample measured can be as low as 0.36 nL, which allows the detection of AIE molecules at only 0.02 pmol. In addition, the miniature sensor was successfully applied to the detection of an AIE-based bioprobe for evaluating the activity of the dipeptidyl-peptidase 4 (DPP-4) inhibitor sitagliptin with an IC₅₀ of 59.80 ± 3.06 nM. The advantages of small device size and nanoliter-scale sample volumes suggest that the proposed sensor is promising for many biosensing applications.

Enhanced voltage generation through electrolyte flow on liquid-filled surfaces

The generation of electrical voltage through the flow of an electrolyte over a charged surface may be used for energy transduction. Here, we show that enhanced electrical potential differences (i.e., streaming potential) may be obtained through the flow of salt water on liquid-filled surfaces that are infiltrated with a lower dielectric constant liquid, such as oil, to harness electrolyte slip and associated surface charge. A record-high figure of merit, in terms of the voltage generated per unit applied pressure, of 0.043 mV Pa⁻¹ is obtained through the use of the liquid-filled surfaces. In comparison with air-filled surfaces, the figure of merit associated with the liquid-filled surface increases by a factor of 1.4. These results lay the basis for innovative surface charge engineering methodology for the study of electrokinetic phenomena at the microscale, with possible application in new electrical power sources.

Superhydrophobic surfaces are expected to increase streaming potential, but are hindered by the presence of air. Here the authors enhance streaming potential by flowing high-dielectric salt water over liquid-filled surfaces infiltrated with low-dielectric liquid, harnessing electric slip and surface charge.

Enhanced Solar Thermal Evaporation of Ethanol-Water Mixtures, through the Use of Porous Media

A significant enhancement of solar irradiation induced evaporation of water, and ethanol-water mixtures, through the use of carbon foam based porous media, is demonstrated. A relationship between the consequent rate of mass loss, with respect to the equilibrium vapor pressure, dynamic viscosity, surface tension, and density, was developed to explain experimental observations. The evaporative heat loss was parametrized through two convective heat transfer coefficients-one related to the surface and another related to the vapor external to the surface. The work promotes a better understanding of thermal processes in binary liquid mixtures with applications ranging from phase separation to distillation and desalination.

A novel and sensitive method for determining vitamin B3 and B7 by pre-column derivatization and high-performance liquid chromatography method with fluorescence detection

A new labeling reagent for vitamin analysis, 2-amino-10-ethyl acridine ketone (AEAO), has been synthesized and successfully applied to the analysis of vitamin B3 and vitamin B7 in different tea samples. The reaction of AEAO with vitamins could proceed easily and quickly in the presence of 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride (EDC) as condensing reagent within 45 min. The derivatives exhibited excellent fluorescence property with excitation and emission wavelengths of 290 nm and 430 nm, respectively. Response surface methodology (RSM) was applied to the optimization of pre-column derivatization. Solid phase extraction with HLB cartridges was used for the extraction and purification of water-soluble vitamins in tea samples. The LODs for vitamin B3 and vitamin B7 were 2.56 and 2.22 ng mL^-1, respectively. The proposed method was successfully applied to the analysis of vitamin B3 and vitamin B7 in different tea samples. The study provided a highly sensitive method for accurate analysis of trace vitamins from natural products.

Targeted spine strengthening exercise and posture training program to reduce hyperkyphosis in older adults: results from the study of hyperkyphosis, exercise, and function (SHEAF) randomized controlled trial

A 6-month randomized controlled trial of spine-strengthening exercise and posture training reduced both radiographic and clinical measures of kyphosis. Participants receiving the intervention improved self-image and satisfaction with their appearance. Results suggest that spine-strengthening exercise and postural training may be an effective treatment option for older adults with hyperkyphosis.

INTRODUCTION

The purpose of the present study is to determine in a randomized controlled trial whether spine-strengthening exercises improve Cobb angle of kyphosis in community-dwelling older adults.

METHODS

We recruited adults ≥60 years with kyphosis ≥40° and enrolled 99 participants (71 women, 28 men), mean age 70.6 ± 0.6 years, range 60-88, with baseline Cobb angle 57.4 ± 12.5°. The intervention included group spine-strengthening exercise and postural training, delivered by a physical therapist, 1-h, three times weekly for 6 months. Controls received four group health education meetings. The primary outcome was change in the gold standard Cobb angle of kyphosis measured from standing lateral spine radiographs. Secondary outcomes included change in kyphometer-measured kyphosis, physical function (modified Physical Performance Test, gait speed, Timed Up and Go, Timed Loaded Standing, 6-Min Walk), and health-related quality of life (HRQoL) (PROMIS global health and physical function indexes, SRS-30 self-image domain). ANCOVA was used to assess treatment effects on change from baseline to 6 months in all outcomes.

RESULTS

There was a -3.0° (95% CI -5.2, -0.8) between-group difference in change in Cobb angle, p = 0.009, favoring the intervention and approximating the magnitude of change from an incident vertebral fracture. Kyphometer-measured kyphosis (p = 0.03) and SRS-30 self-esteem (p < 0.001) showed favorable between-group differences in change, with no group differences in physical function or additional HRQoL outcomes, p > 0.05.

CONCLUSIONS

Spine-strengthening exercise and posture training over 6 months reduced kyphosis compared to control. Our randomized controlled trial results suggest that a targeted kyphosis-specific exercise program may be an effective treatment option for older adults with hyperkyphosis.

TRIAL REGISTRATION NUMBER AND NAME OF TRIAL REGISTER

ClinicalTrials.gov; identifier NCT01751685.

Spine fracture prevalence in a nationally representative sample of US women and men aged ≥40 years: results from the National Health and Nutrition Examination Survey (NHANES) 2013-2014

Spine fracture prevalence is similar in men and women, increasing from <5 % in those <60 to 11 % in those 70-79 and 18 % in those ≥80 years. Prevalence was higher with age, lower bone mineral density (BMD), and in those meeting criteria for spine imaging. Most subjects with spine fractures were unaware of them.

INTRODUCTION

Spine fractures have substantial medical significance but are seldom recognized. This study collected contemporary nationally representative spine fracture prevalence data.

METHODS

Cross-sectional analysis of 3330 US adults aged ≥40 years participating in NHANES 2013-2014 with evaluable Vertebral Fracture Assessment (VFA). VFA was graded by semiquantitative measurement. BMD and an osteoporosis questionnaire were collected.

RESULTS

Overall spine fracture prevalence was 5.4 % and similar in men and women. Prevalence increased with age from <5 % in those <60 to 11 % in those 70-79 and 18 % in those ≥80 years. Fractures were more common in non-Hispanic whites and in people with lower body mass index and BMD. Among subjects with spine fracture, 26 % met BMD criteria for osteoporosis. Prevalence was higher in subjects who met National Osteoporosis Foundation (NOF) criteria for spine imaging (14 vs 4.7 %, P < 0.001). Only 8 % of people with a spine fracture diagnosed by VFA had a self-reported fracture, and among those who self-reported a spine fracture, only 21 % were diagnosed with fracture by VFA.

CONCLUSION

Spine fracture prevalence is similar in women and men and increases with age and lower BMD, although most subjects with spine fracture do not meet BMD criteria for osteoporosis. Since most (>90 %) individuals were unaware of their spine fractures, lateral spine imaging is needed to identify these women and men. Spine fracture prevalence was threefold higher in individuals meeting NOF criteria for spine imaging (∼1 in 7 undergoing VFA). Identifying spine fractures as part of comprehensive risk assessment may improve clinical decision making.

Trends in osteoporosis and low bone mass in older US adults, 2005-2006 through 2013-2014

This study examined trends in osteoporosis and low bone mass in older US adults between 2005 and 2014 using bone mineral density (BMD) data from the National Health and Nutrition Examination Survey (NHANES). Osteoporosis and low bone mass appear to have increased at the femur neck but not at the lumbar spine during this period.

INTRODUCTION

Recent preliminary data from Medicare suggest that the decline in hip fracture incidence among older US adults may have plateaued in 2013-2014, but comparable data on BMD trends for this time period are currently lacking. This study examined trends in the prevalence of osteoporosis and low bone mass since 2005 using BMD data from NHANES. The present study also updated prevalence estimates to 2013-2014 and included estimates for non-Hispanic Asians.

METHODS

Femur neck and lumbar spine BMD by DXA were available for 7954 adults aged 50 years and older from four NHANES survey cycles between 2005-2006 and 2013-2014.

RESULTS

Significant trends (quadratic or linear) were observed for the femur neck (mean T-score and osteoporosis in both sexes; low bone mass in women) but not for the lumbar spine. The trend in femur neck status was somewhat U-shaped, with prevalences being most consistently significantly higher (by 1.1-6.6 percentage points) in 2013-2014 than 2007-2008. Adjusting for changes in body mass index, smoking, milk intake, and physician's diagnosis of osteoporosis between surveys did not change femur neck trends. In 2013-2014, the percent of older adults with osteoporosis was 6% at the femur neck, 8% at the lumbar spine, and 11% at either site.

CONCLUSIONS

There was some evidence of a decline in femur neck BMD between 2005-2006 and 2013-2014, but not in lumbar spine BMD. Changes in the risk factors that could be examined did not explain the femur neck BMD trends.

Myricetin protects cardiomyocytes from LPS-induced injury

BACKGROUND

Sepsis-induced cardiomyopathy is a well-known cause of mortality. Recent evidence has highlighted the important role of myricetin in anti-inflammation and anti-oxidative stress. However, little is known about its effect on endotoxin-induced cardiomyopathy. We examined the effect of myricetin on lipopolysaccharide (LPS)-induced cardiomyocyte injury and the underlying mechanisms in vitro.

METHODS

mRNA expression of interleukin (IL)-1beta, IL-6, and tumor necrosis factor (TNF)-alpha was examined via reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Protein expression levels of NF-κB/p65, IκB, IL-1beta, IL-6, and TNF-alpha were assesses via Western blotting. Immunofluorescence (IF) was used to determine the nuclear translocation of p65. Commercial kits were employed to detect the level of oxidative markers and to quantify NF-κB/p65 both in the cytoplasm and the nucleus. Finally, terminal deoxy-nucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) was performed to evaluate the apoptosis of H9c2 cardiomyocytes.

RESULTS

The results showed that myricetin blunted the overexpression of IL-1beta, IL-6, and TNF-alpha markedly by inhibiting the NF-κB/P65 signaling pathway. Furthermore, myricetin treatment led to the downregulation of reactive oxygen species (ROS) accompanied by increased expression of superoxide dismutase and glutathione peroxidase. TUNEL-positive nuclei were rarely detected following myricetin treatment.

CONCLUSION

Our findings suggest that myricetin is a valuable protective agent against endotoxin-induced early inflammatory responses in H9c2 cardiomyocytes, which involves regulation of ROS and the IκB/NF-κb signaling pathway.

[Effects of different carbohydrates on the simulation of human intestinal bacterial flora with in vitro culture]

OBJECTIVE

To investigate the optimal growth condition of human fecal bacterial flora in vitro by comparing the effect of different carbohydrates as cultural media.

METHODS

Three fecal samples (1, 2, 3) were collected and inoculated into a single-stage chemostat system, in which starch medium (VI) and starch polysaccharide medium(XP) were used. Samples were collected for bacterial genomic DNA extraction and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis. Bacterial composition and short chain fatty acid (SCFA) were then analyzed.

RESULTS

The single stage chemostat system reached steady after operating 8 days, when evaluated by the PCR-DGGE. Bacterial 16s rRNA high-throughput sequencing showed that the intestinal bacteria of these three volunteers was mainly composed of four bacterial phyla, namely, Bacteroidetes, Firmicutes, Proteobacteria and Actinobacteria. When the influence of bacterial abundance was considered, the similarity of bacterial composition between the original fecal samples to the harvested flora after culture was 0.847, 0.825, 0.968 in VI medium and 0.927, 0.926, 0.836 in XP medium, respectively. The similarity was decreased to 0.553, 0.580, 0.623 with VI medium and 0.617, 0.520, 0.574 with XP medium, when the number of bacterial species was considered. The variation of host individual also influenced the simulation. VI medium favored fecal sample 3, while XP medium more benefited sample 1 and 2. Bacteroides and Lachnospiraceae_incertae_sedis grew in both VI and XP medium. However, some species were only detected in VI medium and some were specifically found in the XP medium. The SCFA concentration in fermenters was 15-35 mmol/L, mainly propionate and butyrate.

CONCLUSIONS

The chemostat system works for stimulating human gut bacterial flora in vitro. The bacterial composition is affected by different carbohydrate in the culture medium yet with close simulation higher than 80%.

Jagged 1 is a major Notch ligand along cholangiocarcinoma development in mice and humans

Intrahepatic cholangiocarcinoma (ICC) is a rare yet deadly malignancy with limited treatment options. Activation of the Notch signalling cascade has been implicated in cholangiocarcinogenesis. However, while several studies focused on the Notch receptors required for ICC development, little is known about the upstream inducers responsible for their activation. Here, we show that the Jagged 1 (Jag1) ligand is almost ubiquitously upregulated in human ICC samples when compared with corresponding non-tumorous counterparts. Furthermore, we found that while overexpression of Jag1 alone does not lead to liver tumour development, overexpression of Jag1 synergizes with activated AKT signalling to promote liver carcinogenesis in AKT/Jag1 mice. Histologically, tumours consisted exclusively of ICC, with hepatocellular tumours not occurring in AKT/Jag1 mice. Furthermore, tumours from AKT/Jag1 mice exhibited extensive desmoplastic reaction, an important feature of human ICC. At the molecular level, we found that both AKT/mTOR and Notch cascades are activated in AKT/Jag1 ICC tissues, and that the Notch signalling is necessary for ICC development in AKT/Jag1 mice. In human ICC cell lines, silencing of Jag1 via specific small interfering RNA reduces proliferation and increases apoptosis. Finally, combined inhibition of AKT and Notch pathways is highly detrimental for the in vitro growth of ICC cell lines. In summary, our study demonstrates that Jag1 is an important upstream inducer of the Notch signalling in human and mouse ICC. Targeting Jag1 might represent a novel therapeutic strategy for the treatment of this deadly disease.

Full-length genome sequencing analysis of avian infectious bronchitis virus isolate associated with nephropathogenic infection

Infectious bronchitis virus (IBV) produces infectious bronchitis (IB) disease in poultry worldwide. In spite of proper vaccinations against the IBV, new IBV strains are continually emerging worldwide. In this study, a new highly virulent nephropathogenic IBV strain named CK/CH/XDC-2/2013 was identified from a vaccinated flock with clinical signs of IB in the Jiangsu province of China. The full-length genome sequence of the isolate was 27,714 nucleotides long, and the genome was organized similarly to classical IBV strains. Minimum divergence, phylogenetic analysis, and distance matrix of the genome showed that the CK/CH/XDC-2/2013 isolate had the highest similarity to the IBV BJ strain. The spike glycoprotein (S) gene had the greatest similarity to the nephropathogenic BJ strain and showed an 8 amino acid insertion (YSNGNSDV) at 73 to 80 sites and 3 amino acid deletion at sites 126 to 128 compared to the IBV vaccine strains. A recombination analysis of the S gene showed that the new isolate evolved from the IBV BJ strain and the KM91 vaccine strain. An animal challenge experiment showed a mortality of 60 to 80% in early-age chickens by different inoculation routes. Pathological examinations of the kidneys revealed inflammation, distention with uric acid deposits, and tubular degeneration. It indicated that the CK/CH/XDC-2/2013 isolate has robust kidney tissue tropism, and new nephropathogenic IBV strains are continuously evolving in China.

Trabecular bone scores and lumbar spine bone mineral density of US adults: comparison of relationships with demographic and body size variables

This study examines demographic patterns and body size relationships in trabecular bone score and lumbar spine BMD of US adults from NHANES 2005-2008.

INTRODUCTION

Limited data exist on demographic and body size relationships for trabecular bone score (TBS), a new variable derived from bone texture analysis of lumbar spine dual-energy X-ray absorptiometry (DXA) scans. This study compares demographic patterns and correlations with body size (body mass index (BMI), weight, waist circumference, total body fat, trunk fat, trunk lean) between TBS and lumbar spine bone mineral density (LSBMD) for adults age ≥20 years from the National Health and Nutrition Examination Survey (NHANES) 2005-2008 with BMI in the optimal range for TBS (15-37 kg/m(2)).

METHODS

LSBMD, TBS, body fat, and lean were obtained by DXA. Weight, height, and waist circumference were measured. BMI was calculated from height and weight.

RESULTS

Sex differences in TBS varied by age and race/ethnicity (p sex X age interaction and p sex X race/ethnicity interaction < 0.001). In most of the nine demographic subgroups examined, TBS did not differ by sex (four subgroups) or was significantly higher in women (three subgroups). TBS differences by race/ethnicity were inconsistent in men; in women, non-Hispanic whites (NHWs) had higher TBS than non-Hispanic blacks (NHBs) or Mexican Americans (MAs) in all age groups. In contrast, LSBMD was either significantly higher in men (five subgroups) or did not differ by sex (four subgroups). Race/ethnic differences in LSBMD were consistent across age and sex (NHB > NHW > MA). All body size variables were negatively related to TBS but positively related to LSBMD.

CONCLUSIONS

Demographic patterns and body size relationships differed between TBS and LSBMD.

TGF-β1 and Serpine 1 expression changes in traumatic deep vein thrombosis

The objective of this study was to investigate the expression changes of transforming growth factor β1 (TGF-β1) and Serpine 1 in rats with traumatic deep vein thrombosis (DVT). In total, 60 male Sprague Dawley rats were divided into model (N = 50) and control groups (Group A, N = 10). From the model group, 10 rats were randomly selected after modeling as the pre-thrombosis group (Group B, N = 10), and the remaining 40 rats in the model group were divided into the thrombosis (Group C) and no thrombosis groups (Group D) depending on whether DVT was apparent at 25 h after modeling. All rats were dissected and the total RNAs of the femoral veins were extracted. TGF-β1 and Serpine 1 expression was detected by microarray and polymerase chain reaction (PCR) analyses, and the related signal pathways were analyzed using bioinformatic analysis. Of the 40 rats, DVT was evident in 23, yielding an incidence rate of 57.50%. TGF-β1 and Serpine 1 expression increased significantly at 2.5 h after modeling, while DVT began to form at 25 h after modeling. Both PCR and microarray analysis showed that TGF-β1 and Serpine 1 expression levels were significantly higher in the thrombosis group than in the other groups (P < 0.05). Bioinformatic analysis indicated that TGF-β1 was an upstream regulatory gene of Serpine 1 and could induce Serpine 1 overexpression. Together, these results suggested that TGF-β1 and Serpine 1 overexpression might play an important role in DVT formation and have predictive values.

Comparison of antioxidant activities of different parts from snow chrysanthemum (Coreopsis tinctoria Nutt.) and identification of their natural antioxidants using high performance liquid chromatography coupled with diode array detection and mass spectrometry and 2,2'-azinobis(3-ethylbenzthiazoline-sulfonic acid)diammonium salt-based assay

Snow chrysanthemum (Coreopsis tinctoria Nutt.), a world-widely well-known flower tea material, has attracted more and more attention because of its beneficial health effects such as antioxidant activity and special flavor. In this study, a high performance liquid chromatography coupled with diode array detection and mass spectrometry (HPLC-DAD-MS) and 2,2'-azinobis(3-ethylbenzthiazoline-sulfonic acid)diammonium salt (ABTS) based assay was employed for comparison and identification of antioxidants in different samples of snow chrysanthemum. The results showed that snow chrysanthemum flowers possessed the highest while stems presented the lowest antioxidant capacities. Fourteen detected peaks with antioxidant activity were temporarily identified as 3,4',5,6,7-pentahydroxyflavanone-O-hexoside, chlorogenic acid, 2R-3',4',8-trihydroxyflavanone-7-O-glucoside, flavanomarein, flavanocorepsin, flavanokanin, quercetagitin-7-O-glucoside, 3',5,5',7-tetrahydroxyflavanone-O-hexoside, marein, maritimein, 1,3-dicaffeoylquinic acid, coreopsin, okanin and acetyl-marein by comparing their UV spectra, retention times and MS data with standards or literature data. Antioxidants existed in snow chrysanthemum are quite different from those reported in Chrysanthemum morifolium, a well-known traditional beverage in China, which indicated that snow chrysanthemum may be a promising herbal tea material with obvious antioxidant activity.

Miniaturized optogenetic neural implants: a review

Optogenetics is an exciting new technology that allows targetable fast control and readout of specific neural populations in complex brain circuits. With the rapid development of light-sensitive microbial opsins, substantial gains in understanding the causal relationships between neural activity and behavior in both healthy and diseased brains have been achieved during the last decade. However, the intricate and complex interactions between different neural populations in mammalian brains require novel, implantable, neural interfaces that are capable of manipulating and probing targeted neurons at multiple sites and with high spatiotemporal resolution. Advanced microtechnology has offered the highest potential to meet these demands of optogenetic applications. In this paper, we review a variety of miniaturized optogenetic neural implants developed in recent years, based on different light sources, including lasers, laser diodes, and light-emitting diodes. We then summarize the specifications of these microimplants and their related microfabrication approaches and discuss the major challenges of current techniques and the vision for the future of the field.

Accurate Analysis and Evaluation of Acidic Plant Growth Regulators in Transgenic and Nontransgenic Edible Oils with Facile Microwave-Assisted Extraction-Derivatization

Determination of plant growth regulators (PGRs) in a signal transduction system (STS) is significant for transgenic food safety, but may be challenged by poor accuracy and analyte instability. In this work, a microwave-assisted extraction-derivatization (MAED) method is developed for six acidic PGRs in oil samples, allowing an efficient (<1.5 h) and facile (one step) pretreatment. Accuracies are greatly improved, particularly for gibberellin A3 (-2.72 to -0.65%) as compared with those reported (-22 to -2%). Excellent selectivity and quite low detection limits (0.37-1.36 ng mL(-1)) are enabled by fluorescence detection-mass spectrum monitoring. Results show the significant differences in acidic PGRs between transgenic and nontransgenic oils, particularly 1-naphthaleneacetic acid (1-NAA), implying the PGRs induced variations of components and genes. This study provides, for the first time, an accurate and efficient determination for labile PGRs involved in STS and a promising concept for objectively evaluating the safety of transgenic foods.

The juxtamembrane sequence of the Hepatitis C virus polymerase can affect RNA synthesis and inhibition by allosteric polymerase inhibitors

The Hepatitis C virus (HCV) RNA-dependent RNA polymerase (RdRp), nonstructural protein 5B (NS5B), is anchored in the membrane through a C-terminal helix. A sequence of ca. 12 residues that connects the catalytically competent portion of the RdRp and the C-terminal helix, the juxtamembrane sequence (JMS), has a poorly defined role in RdRp function in a large part since it is translated from a cis-acting RNA element (CRE) that is essential for HCV replication. Using a HCV replicon that transposed a second copy of CRE to the 3' UTR of the HCV replicon, we demonstrate that amino acid substitutions in the JMS were detrimental for HCV replicon replication. Substitutions in the JMS also resulted in a defect in de novo-initiated RNAs synthesis in vitro and in a cell-based reporter assay. A nonnucleoside inhibitor of the NS5B that binds to the catalytic pocket was less potent in inhibiting NS5B in the presence of JMS mutations. The JMS mutants exhibit reduced stability in thermodenaturation assays, suggesting that the JMS helps confer a more stable conformation to NS5B that could impact RNA synthesis.