Joint QTL Mapping and Transcriptome Sequencing Analysis Reveal Candidate Seed-Shattering-Related Genes in Common Buckwheat.

Common buckwheat (Fagopyrum esculentum M.) is an important traditional miscellaneous grain crop. However, seed-shattering is a significant problem in common buckwheat. To investigate the genetic architecture and genetic regulation of seed-shattering in common buckwheat, we constructed a genetic linkage map using the F2 population of Gr (green-flower mutant and shattering resistance) and UD (white flower and susceptible to shattering), which included eight linkage groups with 174 loci, and detected seven QTLs of pedicel strength. RNA-seq analysis of pedicel in two parents revealed 214 differentially expressed genes DEGs that play roles in phenylpropanoid biosynthesis, vitamin B6 metabolism, and flavonoid biosynthesis. Weighted gene co-expression network analysis (WGCNA) was performed and screened out 19 core hub genes. Untargeted GC-MS analysis detected 138 different metabolites and conjoint analysis screened out 11 DEGs, which were significantly associated with differential metabolites. Furthermore, we identified 43 genes in the QTLs, of which six genes had high expression levels in the pedicel of common buckwheat. Finally, 21 candidate genes were screened out based on the above analysis and gene function. Our results provided additional knowledge for the identification and functions of causal candidate genes responsible for the variation in seed-shattering and would be an invaluable resource for the genetic dissection of common buckwheat resistance-shattering molecular breeding.

Directed self-assembled nanoparticles of probucol improve oral delivery: fabrication, performance and correlation.

PURPOSE: We are reporting on the development of a unique drug delivery platform by directed self-assembly technique to improve the oral delivery of hydrophobic drugs. METHODS: Herein, a series of probucol directed self-assembled nanoparticles (PDN) were developed with two components of probucol and surfactant such as Tween 20, Tween 80, D-alpha-tocopheryl polyethylene glycol 1,000 succinate (TPGS) and HS-15, which was respectively named as T20-PDN, T80-PDN, TP-PDN and HS-PDN. The formation of various PDNs was determined by in vitro characterization and the physicochemical properties of these PDNs were determined. Moreover, the performance of PDN in enhancing the oral delivery and possible correlation between the in vitro properties and in vivo performances were investigated. RESULTS: PDN was homogenous nanometer-sized particles with negative surface charge. The cellular uptake of probucol in Caco-2 cell monolayer was respectively increased 1.15, 1.82, 1.59 and 5.31-fold by these PDN. In particular, the oral bioavailability of these PDN was significantly improved 3.0, 4.1, 5.4 and 10.4 folds compared with the free drug suspension. The enhanced cellular uptake and oral bioavailability were correlated with the characters of involved surfactants and the particle size of PDN. CONCLUSIONS: Thereby, the directed self-assembled nanoparticles could provide a new strategy for enhancing the oral delivery of hydrophobic drugs.

Reversal of multidrug resistance by mitochondrial targeted self-assembled nanocarrier based on stearylamine.

Multidrug resistance (MDR) remains one of the major challenges for successful chemotherapy. Herein, we tried to develope a mitochondria targeted teniposide loaded self-assembled nanocarrier based on stearylamine (SA-TSN) to reverse MDR of breast cancer. SA-TSN was nanometer-sized spherical particles (31.59 ± 3.43 nm) with a high encapsulation efficiency (99.25 ± 0.21%). The MDR in MCF-7/ADR cells was obviously reduced by SA-TSN, which mainly attributed to the markedly reduced expression of P-gp, increased percentages in G2 phase, selectively accumulation in mitochondria, decrease of mitochondrial membrane potential, and greatly improved apoptosis. The plasma concentration of teniposide was greatly improved by SA-TSN, and the intravenously administered SA-TSN could accumulate in the tumor site and penetrate into the inner site of tumor in MCF-7/ADR induced xenografts. In particular, the in vivo tumor inhibitory efficacy of SA-TSN in MCF-7/ADR induced models was more effective than that of teniposide loaded self-assembled nanocarrier without stearylamine (TSN) and teniposide solution (TS), which verified the effectiveness of SA-TSN in reversal of MDR. Thereby, SA-TSN has potential to circumvent the MDR for the chemotherapy of breast cancer.

Preparation and mechanical properties analysis of porous structure for bone tissue engineering.

BACKGROUND: With the increasing aging of population, the incidence rate of diseases such as fracture and osteoporosis has been increasing. The demand for implant in Department of orthopedics has increased. The elastic modulus of the existing solid metal implant is much higher than that of human bone tissue, and it is easy to produce stress shielding effect after operation, which causes complications such as loosening of prosthesis and low fusion efficiency. OBJECTIVE: In order to solve the mismatch of elastic modulus between solid metal orthopedic implants and human bone tissue, metal structures with excellent mechanical properties were prepared. METHODS: The porous structure was designed by spatial dot matrix method, and the metal porous structure was prepared based on selective laser melting 3D printing technology. The residual stress in the preparation process was eliminated by vacuum annealing heat treatment, and the static compression experiment was carried out to study the effects of different pore shape and porosity parameters on the compressive yield strength and elastic modulus of porous structure. The performance changes of porous structure before and after heat treatment were compared, and the porous structure meeting the performance requirements of human bone tissue was selected. RESULTS: The porous structure prepared by selective laser melting technology met the requirements of human bone tissue. The elastic modulus was as low as 0.74 GPa and the compressive yield strength is 201.91 MPa; After annealing heat treatment, the compressive yield strength of porous structure decreased, the maximum change was 3.69%, the elastic modulus increased, and the maximum change was 8.69%. CONCLUSIONS: For the porous structure with the same pore shape, the lower the porosity, the better the mechanical properties of the porous structure. For the same porosity, the comprehensive mechanical properties of dodecahedral porous structure were the best and octahedral porous structure was the worst; the porous structure after annealing heat treatment was more conducive to meet the performance requirements of human bone tissue.

Transcriptome and metabolome analyses reveal the key genes related to grain size of big grain mutant in Tartary Buckwheat (Fagopyrum tartaricum).

Grain size with high heritability and stability is an important selection target during Tartary buckwheat breeding. However, the mechanisms that regulate Tartary buckwheat grain development are unknown. We generated transcriptome and metabolome sequencing from 10 and 15 days past anthesis (DPA) grains of big grain mutant (bg1) and WT, and identified 4108 differentially expressed genes (DEGs) including 93 significantly up-regulated differential genes and 85 significantly down-regulated genes in both stages, simultaneously. Meanwhile, we identified DEGs involved in ubiquitin-proteasome pathway, HAI-KU (IKU) pathway, mitogen-activated protein kinase (MAPK) signaling pathway, plant hormone (auxin, brassinosteroids and cytokinins) transduction pathway and five transcription factor families, including APETALA (AP2), GROWTH-REGULATING FACTORS (GRF), AUXIN RESPONSE FACTOR (ARF), WRKY and MYB. Weighted gene co-expression network analysis (WGCNA) was performed and obtained 9 core DEGs. Conjoint analyses of transcriptome and metabolome sequencing screened out 394 DEGs. Using a combined comprehensive analysis, we identified 24 potential candidate genes that encode E3 ubiquitin-protein ligase HIP1, EMBRYO-DEFECTIVE (EMB) protein, receptor-like protein kinase FERONIA (FER), kinesin-4 protein SRG1, and so on, which may be associated with the big-grain mutant bg1. Finally, a quantitative real-time Polymerase Chain Reaction (qRT-PCR) assay was conducted to validate the identified DEGs. Our results provide additional knowledge for identification and functions of causal candidate genes responsible for the variation in grain size and will be an invaluable resource for the genetic dissection of Tartary buckwheat high-yield molecular breeding.

Quantitative determination of puerarin in dog plasma by HPLC and study on the relative bioavailability of sustained release tablets.

To evaluate the bioavailability of puerarin sustained release tablet (SR-Tab.) and Yufengningxin tablet (YU-Tab.), a liquid chromatography method was developed and validated to determine puerarin in dog plasma. Chromatographic separation was performed on Diamonsil C18 column using a mixture of methanol-acetic acid-water (25:6:69, v/v/v) delivered at a flow rate of 1.0 ml/min and detected by UV. 4-Hydroxybenzaldehyde was used as the internal standard. The linear range for puerarin was from 60 to 1800 ng/ml (r=0.9991) with a limit of quantitation of 60 ng/ml. Within-day accuracy and precision ranged from -3.0 to 2.2% and from 1.2 to 4.3%, between-day accuracy and precision ranged from -4.1 to 2.6% and from 1.3 to 5.7%, respectively. The mean extraction recoveries of puerarin determined over the three concentrations were (90.3+/-5.2)%, (95.7+/-1.4)% and (93.1+/-3.5)%. A significant difference was observed in main pharmacokinetic parameters of Tmax, Cmax and AUC0-infinity between puerarin SR-Tab. and YU-Tab. in dogs. The smoother plasma concentrations were obtained from SR-Tab. in dogs and the results were as expected.

Characteristics of bicalutamide solid dispersions and improvement of the dissolution.

The purpose of our study was to formulate and evaluate bicalutamide (BL) solid dispersions (SD). The physicochemical properties were evaluated by differential scanning calorimetry (DSC), Fourier-Transform infrared (FT-IR) spectroscopy, Powder X-ray diffractometry (PXRD), dissolution studies, and stability studies. The dissolution studies demonstrated that the dissolution of BL from BL-SD increased with an increase in carrier content (PVP K30). X-ray assays and DSC results both confirmed the amorphous state of BL in BL-SD. Stability studies conducted after 6 months showed that BL exhibited excellent stability in the solid dispersion of PVP K30 (1:5).