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Kai Dong,1,2 Ying Zhang,2 Hong Rui Ji,2 Ze Lin Guan,2 Dan Yang Wang,2 Zi Yang Guo,2 Shu Jing Deng,2 Bin Yang He,2 Jian Feng Xing,2 Cui Yu You1 1Department of Pharmacy, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of China; 2School of Pharmacy, Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of ChinaCorrespondence: Jian Feng Xing, School of Pharmacy, Xi’an Jiaotong University, 76 Yanta West Road, Xi’an, Shaanxi, 710061, People’s Republic of China, Tel +86-29-82655139, Fax +86-29-82655139, Email xajdxjf@mail.xjtu.edu.cn Cui Yu You, Department of Pharmacy, The First Affiliated Hospital of Xi’an Jiaotong University, 277 Yanta West Road, Xi’an, Shaanxi, 710061, People’s Republic of China, Tel +86-29-85323241, Fax +86-29-85323240, Email ycy720123@163.comBackground: The M1/M2 polarization of intestinal macrophages exerts an essential function in the pathogenesis of ulcerative colitis (UC), which can be adjusted to alleviate the UC symptoms.Purpose: A kind of pH-sensitive lipid calcium phosphate core-shell nanoparticles (NPs), co-loading with dexamethasone (Dex) and its water-soluble salts, dexamethasone sodium phosphate (Dsp), was constructed to comprehensively regulate macrophages in different states towards the M2 phenotype to promote anti-inflammatory effects.Methods: Dex and Dsp were loaded in the outer lipid shell and inner lipid calcium phosphate (Cap) core of the LdCaPd NPs, respectively. Then, the morphology of NPs and methods for determining drug concentration were investigated, followed by in vitro protein adsorption, stability, and release tests. Cell experiments evaluated the cytotoxicity, cellular uptake, and macrophage polarization induction ability of NPs. The in vivo distribution and anti-inflammatory effect of NPs were evaluated through a 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced BALB/c mice ulcerative colitis model.Results: The LdCaPd NPs showed a particle size of about 200 nm and achieved considerable loading amounts of Dex and Dsp. The in vitro and in vivo studies revealed that in the acidic UC microenvironment, the cationic lipid shell of LdCaPd underwent protonated dissociation to release Dex first for creating a microenvironment conducive to M2 polarization. Then, the exposed CaP core was further engulfed by M1 macrophages to release Dsp to restrict the pro-inflammatory cytokines production by inhibiting the activation and function of the nuclear factor kappa-B (NF-κB) through activating the GC receptor and the NF kappa B inhibitor α (I-κBα), respectively, ultimately reversing the M1 polarization to promote the anti-inflammatory therapy.Conclusion: The LdCaPd NPs accomplished the sequential release of Dex and Dsp to the UC site and the inflammatory M1 macrophages at this site, promoting the regulation of macrophage polarization to accelerate the remission of UC symptoms. Keywords: ulcerative colitis, calcium phosphate, macrophage polarization, colon targeted delivery system, dexamethasone

Kai Dong,1,2 Shu-Jing Deng,2 Bin-Yang He,2 Zi-Yang Guo,2 Ze-Lin Guan,2 Xue Leng,2 Rui-Rui Ma,2 Dan-Yang Wang,2 Jian-Feng Xing,2 Cui-Yu You1 1Department of Pharmacy, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of China; 2School of Pharmacy, Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of ChinaCorrespondence: Jian-Feng Xing, School of Pharmacy, Xi’an Jiaotong University, 76 Yanta West Road, Xi’an, 710061, Shaanxi, People’s Republic of China, Tel +86-29-82655139, Fax +86-29-82655139, Email xajdxjf@mail.xjtu.edu.cn Cui-Yu You, Department of Pharmacy, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of China, Tel +86-29-85323241, Fax +86-29-85323240, Email ycy720123@163.comBackground: As the first-line drug to treat ulcerative colitis (UC), long-term use of glucocorticoids (GCs) produces severe toxic and side effects. Local administration as enema can increase the local GCs concentrations and reduce systemic exposure to high oral doses by directly delivering GCs to the inflammation site in the distal colorectum. However, UC patients are often accompanied by diarrhea, leading to the short colonic residence time of GCs and failure to exert their function fully.Purpose: A kind of mucoadhesive nanoparticles (NPs) loading different dexamethasone derivatives (DDs) were developed, which could attach to the positively charged inflammatory colonic mucosa through electrostatic adsorption after administered by enema, thereby improving the local concentration and achieving effective targeted therapy for UC.Methods: Two DDs, dexamethasone hemisuccinate and dexamethasone phosphate, were synthesized. In NPs preparation, The core PEI-DDs NPs were built by the electrostatic adsorption of DDs and the cationic polymer polyethyleneimine (PEI). Then, the natural polyanionic polysaccharide sodium alginate (SA) was electronically coated around NPs to construct the final SA-PEI-DDs NPs, followed by the in vitro stability and release tests, in vitro and in vivo colonic mucosal adhesion tests. In the in vivo anti-UC test, the experimental colitis mice were induced by 2,4,6-trinitrobenzenesulfonic acid. The body weight and disease activity index changes were measured, and the myeloperoxidase activity, pro-inflammatory cytokines concentration, and hematoxylin and eosin staining were also investigated to evaluate the therapeutic effect of NPs.Results: The structures of two DDs were demonstrated by 1H-NMR and MS. Both NPs were negatively charged and achieved high loading efficiency of DDs, while their particle sizes were significantly different. NPs showed good stability and sustained release properties in the simulated colonic environment. Moreover, the negative charge on the of NPs surface made them easier to adhere to the positively charged inflammatory colonic mucosa, thereby enhancing the enrichment and retention of DDS in the colitis site. Furthermore, the NPs exhibited better therapeutic effects than free Dex on the experimental colitis mice induced by TNBS through the enema rectal.Conclusion: These results indicated the mucoadhesive NPs as a kind of novel nano-enema showed great potential to achieve efficient treatment on UC.Keywords: ulcerative colitis, glucocorticoids, mucoadhesive, polyethyleneimine, sodium alginate

Kai Dong,1 Yan Yan,2 Pengchong Wang,2 Xianpeng Shi,2 Lu Zhang,2 Ke Wang,2 Jianfeng Xing,2 Yalin Dong1 1Department of Pharmacy, The First Affiliated Hospital of Xi’an Jiaotong University, 2School of Pharmacy, Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of China Abstract: In this study, a type of multifunctional mixed micelles were prepared by a novel biodegradable amphiphilic polymer (MPEG-SS-2SA) and a multidrug resistance (MDR) reversal agent (D-α-tocopheryl polyethylene glycol succinate, TPGS). The mixed micelles could achieve rapid intracellular drug release and reversal of MDR. First, the amphiphilic polymer, MPEG-SS-2SA, was synthesized through disulfide bonds between poly (ethylene glycol) monomethyl ether (MPEG) and stearic acid (SA). The structure of the obtained polymer was similar to poly (ethylene glycol)-phosphatidylethanolamine (PEG-PE). Then the mixed micelles, MPEG-SS-2SA/TPGS, were prepared by MPEG-SS-2SA and TPGS through the thin film hydration method and loaded paclitaxel (PTX) as the model drug. The in vitro release study revealed that the mixed micelles could rapidly release PTX within 24 h under a reductive environment because of the breaking of disulfide bonds. In cell experiments, the mixed micelles significantly inhibited the activity of mitochondrial respiratory complex II, also reduced the mitochondrial membrane potential, and the content of adenosine triphosphate, thus effectively inhibiting the efflux of PTX from cells. Moreover, in the confocal laser scanning microscopy, cellular uptake and 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assays, the MPEG-SS-2SA/TPGS micelles achieved faster release and more uptake of PTX in Michigan Cancer Foundation-7/PTX cells and showed better antitumor effects as compared with the insensitive control. In conclusion, the biodegradable mixed micelles, MPEG-SS-2SA/TPGS, could be potential vehicles for delivering hydrophobic chemotherapeutic drugs in MDR cancer therapy. Keywords: reversal of multidrug resistance, reduction-sensitive, disulfide bond, mixed micelles, MCF-7/PTX cells

Multiple resonance (MR) boron-nitrogen doped polycyclic aromatic hydrocarbons (BN-PAHs) have shown compelling thermally activated delayed fluorescence (TADF), surpassing those of their hydrocarbon analogues. However, the structural variety of π-extended BN-PAHs remains narrow. In this study, we synthesized three double helical BN-doped nanographenes (BN-NGs), 2 a-2 c, and three heptagon-embedded BN-NGs, 1 a-1 c, by π-extension of the MR core. During the formation of 2 a, a nanographene with one heptagon (1 a) was obtained, whereas further dehydrocyclization of the [6]helicene units within 2 b and 2 c led to heptagon structures, yielding other two BN-NGs containing double heptagons (1 b and 1 c). These BN-NGs (2 a-2 c and 1 a-1 c) showed pronounced redshifts of 100-190 nm compared to the parent MR core, while preserving the TADF characteristics and prolonging the delayed fluorescence lifetime to the millisecond level. Furthermore, the integration of a heptagon ring into 1 a-1 c expanded the conjugation, reduced the oxidation potentials, and yielded a more flexible framework compared to those of 2 a-2 c. The enantiomers of 2 a-2 c, 1 a, and 1 c were resolved and their chiroptical properties were studied. Notably, 1 a and 1 c exhibited increased chiroptical dissymmetry factors., (© 2024 Wiley-VCH GmbH.)

Ring contraction of metallacyclobutadiene to metallacyclopropene is rare because of the increasing strain from a four-membered ring to a three-membered one. Here we demonstrate a new series of reactions of metallabenzocyclobutadiene to metallabenzocyclopropene via density functional theory calculations. The results suggest that these reactions are thermodynamically favorable ranging from -17.4 to -29.4 kcal mol -1 , and a low reaction barrier (10.3 kcal mol -1 ) is achieved when the metal center is Ru and the ligands are one cyanide and one chloride. Further analysis suggests that a strengthened binding energy helps stabilize the transition state in the protonation process. The aromaticity during the reaction was investigated using the electron density of delocalized bonds (EDDB), isomerization stabilization energy, and isodesmic reactions. The EDDB shows that the π-conjugation is disrupted in the intermediate, and then σ-aromaticity is generated and dominant in the products. Our findings could be helpful for experimentalists in developing novel ring contraction reactions driven by aromaticity.

The incorporation of pentagon-heptagon pairs into helical nanographenes lacks a facile synthetic route, and the impact of these pairs on chiroptical properties remains unclear. In this study, a method for the stepwise construction of pentagon-heptagon pairs in helical nanographenes by the dehydrogenation of [6]helicene units was developed. Three helical nanographenes containing pentagon-heptagon pairs were synthesized and characterized using this approach. A wide variation in the molecular geometries and photophysical properties of these helical nanographenes was observed, with changes in the helical length of these structures and the introduction of the pentagon-heptagon pairs. The embedded pentagon-heptagon pairs reduced the oxidation potential of the synthesized helical nanographenes. The high isomerization energy barriers enabled the chiral resolution of the helicene enantiomers. Chiroptical investigations revealed remarkably enhanced circularly polarized luminescence and luminescence dissymmetry factors with an increasing number of the pentagon-heptagon pairs., (© 2024 Wiley-VCH GmbH.)

Objective: Two-dimensional shear wave elastography (2-D SWE) has been proven to detect hyperlipidemia-induced elastic abnormality in the corpus cavernosum. This study investigated cytological factors affecting the elasticity of the corpus cavernosum in rabbits with hyperlipidemia using single-cell RNA sequencing (scRNA-seq)., Methods: Male New Zealand white rabbits were randomly divided into a hyperlipidemia group (high-cholesterol diet) and a control group (standard diet). Penile 2-D SWE was performed to detect the elastic abnormality in the corpus cavernosum. ScRNA-seq was performed to observe cellular changes in the corpus cavernosum of rabbits with hyperlipidemia. Immunohistochemistry, immunofluorescence and histological examinations were conducted to verify the results of scRNA-seq., Results: Two-dimensional SWE revealed that the Young's modulus of the corpus cavernosum was significantly greater in the hyperlipidemia group than that in the control group (p < 0.001). Histological findings revealed extracellular matrix accumulation within the corpus cavernosum, with stronger staining of collagen types I and Ⅲ. ScRNA-seq revealed that fibroblasts, smooth muscle cells, and endothelial cells were the major cell types in the corpus cavernosum. A novel subtype of fibroblasts (myofibroblast) was discovered in the hyperlipidemia group, which was verified by immunofluorescence staining and gene ontology analysis. Fibroblasts, smooth muscle cells and endothelial cells were three cellular sources for myofibroblasts., Conclusion: Myofibroblasts are activated and proliferate and secrete large amounts of collagen fibers in the corpus cavernosum during hyperlipidemia, leading to abnormal Young's modulus detected by 2-D SWE and their recognition as a new factor affecting the hyperlipidemia-induced elastic abnormality of the corpus cavernosum., Competing Interests: Conflict of interest The authors declare no competing interests., (Copyright © 2023 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.)

Background: As a new ultrasound technology, 2-dimensional shear wave elastography (2D-SWE) can evaluate the elastic characteristics of penile tissue. However, no studies have reported the main factors affecting the shear wave elastic quantitative measurement (SWQ) in penile tissue., Objectives: To analyze the main factors affecting the SWQ reflecting the elastic characteristics of penile tissue by 2D-SWE., Methods: Twenty healthy male Sprague-Dawley rats (5-60 weeks old) were selected for this study. We performed the 2D-SWE examination on the penis using the Aixplorer ultrasound system, with SWQ as the measurement index. We performed penile immunohistochemistry analysis with the positive area proportion (PAP) of alpha-smooth muscle actin (PAP S ) and type III collagen fiber (PAP C ) as the outcomes. Then, we conducted multiple linear regression analysis to explore the correlation of SWQ with PAP S and PAP C and established the regression equation., Results: The multiple linear regression analysis showed that the linear regression equation (SWQ = 10.376 - 0.05 PAP S - 0.07 PAP C ) was statistically significant ( F = 21.153, P < 0.001). The content of smooth muscle cells (SMCs) and collagen fibers was negatively correlated with SWQ, affecting 42.6% of the total variation in SWQ ( R 2 = 0.426)., Conclusions: SMCs and collagen fibers are the main factors affecting the SWQ value of penile tissue and the primary tissue components determining the SWQ when using 2D-SWE to quantitatively evaluate the elastic characteristics of penile tissue., (© 2023 Wan-Ting Rao et al., published by Sciendo.)

The synthesis of well-defined nanocarbon multilayers, beyond the bilayer structure, is still a challenging goal. Herein, two trilayer nanographenes were synthesized by covalently linking nanographene layers through helicene bridges. The structural characterization of the trilayer nanographenes revealed a compact trilayer-stacked architecture. The introduction of a furan ring into the helicene linker modulates the interlayer overlap and π-conjugation of the trilayer nanographenes, enabling the tuning of the interlayer coupling, as demonstrated by optical, electrochemical, and theoretical analyses. Both synthesized trilayer nanographenes are rigid chiral nanocarbons and show a chirality transfer from the helicene moiety to the stacked nanographene layers. These helical trilayer nanographenes reported here represent the covalently linked multilayer nanographenes rather than bilayer ones, showing the tunable multilayer stacking structure.

Nanographenes are inclined to assemble into stacked columnar structures that are stabilized by π-π interactions, whereas other supramolecular structures of nanographenes, such as prisms and cages, are rarely investigated. Herein, a diazananographene was synthesized, and then assembled with a coordination unit, thereby producing a triangular metallaprism. After adding C 60 or C 70 , the triangular metallaprism was transformed into a square tetramer, which encapsulated a pair of C 60 or C 70 molecules. The formed host-guest complex demonstrated efficient energy transfer from the diazananographene shell to the C 60 cores. The emission intensity of the capsulated C 60 was enhanced remarkably, compared with free C 60 , due to an increased quantum yield and optical absorption coefficient. This work demonstrates the versatility of nanographene-based supramolecular architectures beyond columnar stacking and their ability to enhance the emission of otherwise non-emissive fullerene., (© 2022 Wiley-VCH GmbH.)

N6-methyladenine (6mA) DNA modification has been detected in several eukaryotic organisms, in some of them, it plays important role in the regulation process of stress-resistance response. However, the genome-wide distribution patterns and potential functions of 6mA DNA modification in halophyte Seashore paspalum ( Paspalum vaginatum ) remain largely unknown. Here, we examined the 6mA landscape in the P. vaginatum genome by adopting single molecule real-time sequencing technology and found that 6mA modification sites were broadly distributed across the P. vaginatum genome. We demonstrated distinct 6mA methylation levels and 6mA distribution patterns in different types of transcription genes, which hinted at different epigenetic rules. Furthermore, the moderate 6mA density genes in P. vaginatum functionally correlated with stress resistance, which also maintained a higher transcriptional level. On the other hand, a specific 6mA distribution pattern in the gene body and near TSS was observed in gene groups with higher RNA expression, which maybe implied some kind of regularity between 6mA site distribution and the protein coding genes transcription was possible. Our study provides new insights into the association between 6mA methylation and gene expression, which may also contribute to key agronomic traits in P. vaginatum., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Hao, Xing, Hu, Wang, Tang and Liao.)

This study explored the usefulness of two-dimensional shear wave elastography (2D-SWE) in the early assessment of corpora cavernosa fibrosis (CCF). New Zealand male rabbits were randomly assigned to an experimental group or a control group. Recombinant human transforming growth factor beta 1 (TGF-β1) was injected into the dorsal penis tissue of rabbits in the experimental group. Conventional ultrasound and 2D-SWE examinations were performed before and 20 days after injection. Penile histological analysis was performed by hematoxylin-eosin staining, sirius red staining, and immunohistochemistry. Measurement of 2D-SWE examination results was performed using shear wave elastography quantitative measurement (SWQ). Histological analysis outcomes were the proportion of smooth muscle cells (SMCs), collagen fibers (CFs), collagen type I (Col I), and collagen type III (Col III), as well as the SMCs/CFs ratio, measured by sirius red staining. Other histological analysis outcomes were the positive area proportion (PAP) of TGF-β1 (PAP T ), fibronectin (PAP F ), and Col III (PAP C ), measured by immunohistochemistry. After recombinant human TGF-β1 injection, SWQ was higher in the experimental group than that in the control group (P < 0.001); however, there were no differences in conventional ultrasound results. There were significant differences in histological outcomes between the two groups (all P < 0.05). These results indicated that 2D-SWE was superior for identifying early histological changes in CCF., Competing Interests: None

Long nanopore reads are advantageous in de novo genome assembly. However, nanopore reads usually have broad error distribution and high-error-rate subsequences. Existing error correction tools cannot correct nanopore reads efficiently and effectively. Most methods trim high-error-rate subsequences during error correction, which reduces both the length of the reads and contiguity of the final assembly. Here, we develop an error correction, and de novo assembly tool designed to overcome complex errors in nanopore reads. We propose an adaptive read selection and two-step progressive method to quickly correct nanopore reads to high accuracy. We introduce a two-stage assembler to utilize the full length of nanopore reads. Our tool achieves superior performance in both error correction and de novo assembling nanopore reads. It requires only 8122 hours to assemble a 35X coverage human genome and achieves a 2.47-fold improvement in NG50. Furthermore, our assembly of the human WERI cell line shows an NG50 of 22 Mbp. The high-quality assembly of nanopore reads can significantly reduce false positives in structure variation detection.

DNA 6mA modification, an important newly discovered epigenetic mark, plays a crucial role in organisms and has been attracting more and more attention in recent years. The soybean is economically the most important bean in the world, providing vegetable protein for millions of people. However, the distribution pattern and function of 6mA in soybean are still unknown. In this study, we decoded 6mA modification to single-nucleotide resolution in wild and cultivated soybeans, and compared the 6mA differences between cytoplasmic and nuclear genomes and between wild and cultivated soybeans. The motif of 6mA in the nuclear genome was conserved across the two kinds of soybeans, and ANHGA was the most dominant motif in wild and cultivated soybeans. Genes with 6mA modification in the nucleus had higher expression than those without modification. Interestingly, 6mA distribution patterns in cytoplasm for each soybean were significantly different from those in nucleus, which was reported for the first time in soybean. Our research provides a new insight in the deep analysis of cytoplasmic genomic DNA modification in plants., (Copyright © 2020 Yuan, Xing, Luan, Ji, Guo, Xie and Zhang.)

N6-methyladenosine (6mA) DNA modification played an important role in epigenetic regulation of gene expression. And the aberrational expression of non-coding genes, as important regular elements of gene expression, was related to many diseases. However, the distribution and potential functions of 6mA modification in non-coding RNA (ncRNA) genes are still unknown. In this study, we analyzed the 6mA distribution of ncRNA genes and compared them with protein-coding genes in four species ( Arabidopsis thaliana , Caenorhabditis elegans , Drosophila melanogaster , and Homo sapiens ) using single-molecule real-time (SMRT) sequencing data. The results indicated that the consensus motifs of short nucleotides at 6mA location were highly conserved in four species, and the non-coding gene was less likely to be methylated compared with protein-coding gene. Especially, the 6mA-methylated lncRNA genes were expressed significant lower than genes without methylation in A. thaliana ( p = 3.295e-4), D. melanogaster ( p = 3.439e-11), and H. sapiens ( p = 9.087e-3).. The detection and distribution profiling of 6mA modification in ncRNA regions from four species reveal that 6mA modifications may have effects on their expression level., (Copyright © 2020 Li, Zhang, Luan, Xing, Chen and Xie.)

N 6 -methyladenine (6mA) DNA modification has been detected in several eukaryotic organisms, where it plays important roles in gene regulation and epigenetic memory maintenance. However, the genome-wide distribution patterns and potential functions of 6mA DNA modification in woodland strawberry ( Fragaria vesca ) remain largely unknown. Here, we examined the 6mA landscape in the F. vesca genome by adopting single-molecule real-time sequencing technology and found that 6mA modification sites were broadly distributed across the woodland strawberry genome. The pattern of 6mA distribution in the long non-coding RNA was significantly different from that in protein-coding genes. The 6mA modification influenced the gene transcription and was positively associated with gene expression, which was validated by computational and experimental analyses. Our study provides new insights into the DNA methylation in F. vesca ., (Copyright © 2020 Xie, Xing, Zhang, Liu, Luan, Zhu, Ling, Xiao, Song, Zheng and Chen.)

Background: DNA methylation is an important epigenetic modification. Recently the developed single-molecule real-time (SMRT) sequencing technology provided an efficient way to detect DNA N6-methyladenine (6mA) modification that played an important role in epigenetic and positively regulated gene expression. In addition, the gene expression was also regulated by genetic variation. However, the relationship between DNA 6mA modification and variation is still unknown., Results: We collected the SMRT long-reads DNA, Illumina short reads DNA and RNA datasets from the young leaves of Herrania umbratica, and used them to detect 35,654 6mA modification sites, 829,894 DNA variations and 60,672 RNA variations respectively, among which, there are 303 DNA variations and 19 RNA variations with 6mA modification, and 57,468 transmitted genetic variations from DNA to RNA. The results illustrated that the genes with 6mA modification were significant disadvantage to mutate than those genes without modification (p-value< 4.9e-08). And result from the linear regression model showed the 6mA densities of genes were associated with the transmitted variations type 0/1 to 1/1 (p-value < 0.001)., Conclusions: The variations of DNA and RNA in genes with 6mA modification were significant less than those in unmodified genes. Furthermore, the variations in 6mA modified genes were easily transmitted from DNA to RNA, especially the transmitted variation from DNA heterozygote to RNA homozygote.

Eukaryotic DNA methylation has been receiving increasing attention for its crucial epigenetic regulatory function. The recently developed single-molecule real-time (SMRT) sequencing technology provides an efficient way to detect DNA N6-methyladenine (6mA) and N4-methylcytosine (4mC) modifications at a single-nucleotide resolution. The family Rosaceae contains horticultural plants with a wide range of economic importance. However, little is currently known regarding the genome-wide distribution patterns and functions of 6mA and 4mC modifications in the Rosaceae. In this study, we present an integrated DNA 6mA and 4mC modification database for the Rosaceae (MDR, http://mdr.xieslab.org). MDR, the first repository for displaying and storing DNA 6mA and 4mC methylomes from SMRT sequencing data sets for Rosaceae, includes meta and statistical information, methylation densities, Gene Ontology enrichment analyses, and genome search and browse for methylated sites in NCBI. MDR provides important information regarding DNA 6mA and 4mC methylation and may help users better understand epigenetic modifications in the family Rosaceae., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest.

Structural alterations in fibroelastic components of the penile corpus cavernousum (CC) may impair its compliance, resulting in venous leakage and erectile dysfunction (ED). Our study evaluated the effectiveness of noninvasive two-dimensional shear-wave elastography (2-D SWE) in quantifying penile CC lesions in rabbits with hyperlipidemia-induced ED. A total of 12 New Zealand white rabbits were randomly divided into two groups. Six were fed a high-cholesterol diet containing 2% cholesterol and 8.5% lard for 10 weeks and the other six were fed normal diet as controls. We measured the shear-wave elastic quantitative (SWQ) value of penile CC by 2-D SWE. Erectile function was investigated by intracavernous injection of papaverine, and immunohistochemical (IHC) staining and the western blot analysis to determine the penile CC lesions. After 10 weeks, the SWQ values obtained from penile CC were remarkably higher in the high-cholesterol-fed compared with the control group, and the ΔICP (ICP plateau minus ICP baseline)/MAP (ICP: intracavernous pressure, MAP: mean arterial pressure) was markedly decreased. The IHC staining and western blot revealed extracellular matrix (ECM) accumulation in penile cavernous tissues, and the smooth muscle cell (SMC) phenotypic transition was affected, as indicated by reduced alpha-smooth muscle actin and calponin-1 expression and increased phospho-myosin light chain 20 (p-MLC 20 )/MLC 20 and osteopontin expression. Hyperlipidemia resulted in ECM accumulation accompanied with SMC phenotypic transition in penile CC and impaired the erectile function eventually. These might, in turn, lead to variations in the SWQ values. It suggests that 2-D SWE may be a novel, noninvasive and effective approach that distinguishes penile CC lesions secondary to hyperlipidemia from normal., Competing Interests: None

DNA N6-methyladenine (6mA) modifications expand the information capacity of DNA and have long been known to exist in bacterial genomes. Xanthomonas oryzae pv. Oryzicola (Xoc) is the causative agent of bacterial leaf streak, an emerging and destructive disease in rice worldwide. However, the genome-wide distribution patterns and potential functions of 6mA in Xoc are largely unknown. In this study, we analyzed the levels and global distribution patterns of 6mA modification in genomic DNA of seven Xoc strains (BLS256, BLS279, CFBP2286, CFBP7331, CFBP7341, L8 and RS105). The 6mA modification was found to be widely distributed across the seven Xoc genomes, accounting for percent of 3.80, 3.10, 3.70, 4.20, 3.40, 2.10, and 3.10 of the total adenines in BLS256, BLS279, CFBP2286, CFBP7331, CFBP7341, L8, and RS105, respectively. Notably, more than 82% of 6mA sites were located within gene bodies in all seven strains. Two specific motifs for 6 mA modification, ARGT and AVCG, were prevalent in all seven strains. Comparison of putative DNA methylation motifs from the seven strains reveals that Xoc have a specific DNA methylation system. Furthermore, the 6 mA modification of rpfC dramatically decreased during Xoc infection indicates the important role for Xoc adaption to environment.

Efficient small interfering RNA (siRNA) delivery in the presence of serum is of crucial importance for effective gene therapy. Fluorinated vectors are considered to be attractive candidates for siRNA-mediated gene therapy because of their delivery efficacy in serum-containing media. However, the mechanisms driving the superior gene transfection behavior of fluorinated vectors are still not well-understood, and comprehensive investigations are warranted. Herein, we fabricated a library of perfluorooctanoyl fluoride-fluorinated (PFF-fluorinated) oligoethylenimines (f x OEIs, x is the PFF:OEI feeding ratio), which can readily form nanoassemblies (f x OEI NAs) capable of efficient siRNA delivery in cells cultured in medium both devoid of and supplemented with fetal bovine serum (FBS). The gene silencing test in serum-containing medium revealed that the f 0.7 OEI/siRNA NAs achieved a luciferase silencing of ∼88.4% in Luc-HeLa cells cultured in FBS-containing medium, which was almost 2-fold greater than the silencing efficacy of siRNA delivered by the commercially available vector Lipo 2000 (∼48.8%). High levels of apolipoprotein B silencing were also achieved by f 0.7 OEI/siRNA NAs in vivo. For an assessment of the underlying mechanisms of the efficacy of gene silencing of fluorinated vectors, two alkylated OEIs, aOEI-C8 and aOEI-C12, were fabricated as controls with similar molecular structure and hydrophobicity to that of f 0.7 OEI, respectively. In vitro investigations showed that the superior gene delivery exhibited by f 0.7 OEI NAs derived from the potent endosomal disruption capability of fluorinated vectors in the presence of serum, which was essentially attributed to the serum protein adsorption resistance of the f 0.7 OEI NAs. Therefore, this work provides an innovative approach to siRNA delivery as well as insights into fluorine-associated serum resistance.

Liver metabolism is commonly considered the major determinant in drug discovery and development. Many in vitro drug metabolic studies have been developed and applied to understand biotransformation. However, these methods have disadvantages, resulting in inconsistencies between in vivo and in vitro experiments. A major factor is that they are static systems that do not consider the transport process in the liver. Here we developed an in vitro dynamic metabolic system (Bio-PK metabolic system) to mimic the human pharmacokinetics of tolbutamide. Human liver microsomes (HLMs) encapsulated in a F127'-Acr-Bis hydrogel (FAB hydrogel) were placed in the incubation system. A microdialysis sampling technique was used to monitor the metabolic behavior of tolbutamide in hydrogels. The measured results in the system were used to fit the in vitro intrinsic clearance of tolbutamide with a mathematical model. Then, a PBPK model that integrated the corresponding in vitro intrinsic clearance was developed to verify the system. Compared to the traditional incubation method, reasonable PK profiles and the in vivo clearance of tolbutamide could be predicted by integrating the intrinsic clearance of tolbutamide obtained from the Bio-PK metabolic system into the PBPK model. The predicted maximum concentration (C max ), area under the concentration-time curve (AUC), time to reach the maximum plasma concentration (T max ) and in vivo clearance were consistent with the clinically observed data. This novel in vitro dynamic metabolic system can compensate for some limitations of traditional incubation methods; it may provide a new method for screening compounds and predicting pharmacokinetics in the early stages, supporting the development of compounds.

Objective: To explore the effect of c-fos on multidrug resistance of laryngeal cancer TU177 cells. Method: Increasing drug concentration gradient is adopted to establish the stability of the laryngeal cancer drug resistance in cell line; RT-PCR and Western blot were used to detect difference of the c-fos between TU177 and TU177/VCR cells; plasmids with human c-fos knockdown or over expression were transfected into TU177/VCR and TU177 cells respectively, and the effects of different treatment on cell proliferation were investigated with MTT. Results: The drug resistance of TU177/VCR cells was 26.25-fold in vincristine (VCR), 7.33-fold in Paclitaxel (TAX), 2.41 in cisplatin (DDP), and 5.50 in 5-fluorouracil (5-FU), comparing with TU177( P <0.05). The TU177/VCR cells had significantly higher c-fos expression compared to TU177 cells( P <0.05). The results showed that the IC(50) values of 5-FU for the NC group and c-fos shRNA group were (306.2±6.3)μmol/L and (81.3±3.9)μmol/L, respectively, which was decreased by 73% in the c-fos shRNA group compared to that in the NC group ( P <0.05). Similarly, the results showed that the IC(50) values for 5-FU were (55.3±9.4) μmol/L in NC group and (288.1±7.3)μmol/L in c-fos WT group, which was increased 5.21-fold in c-fos WT cells. Conclusion: C-fos plays important role in multidrug resistance of larynx cancer cell TU177/VCR, and might become a new molecular target for laryngeal cancer treatment.

Objective: To explore the expression of FAT1 in esophageal squamous cell carcinoma (ESCC) tissues, and its effect on cell proliferation. Methods: The expression levels of FAT1 protein in human ESCC tissues and matched adjacent normal tissues were determined by immunohistochemistry (IHC). Lentivirus based knockdown of FAT1 was carried out in YSE2 and Colo680N cell lines and 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) assays was performed to examine the effect of FAT1 on the proliferation of these ESCC cells. Colony formation assay was used to detect the colony formation ability. Flow cytometry was performed to analyze the cell cycle and apoptosis. The expression levels of cell cycle markers in FAT1 knock out ESCC cell lines were detected by real-time quantitative reverse transcription polymerase chain reaction(qRT-PCR) and Western blot. Results: The relative expression of FAT1 in ESCC tissues was 66.97±21.53, significantly lower than 78.13±16.76 of adjacent normal tissues( P <0.05). Knockdown of FAT1 promoted cell proliferation and colony formation. In YSE2 cell, the division time in negative control (NC) group was (1 570±51) min, significantly longer than (1 356±31) min in shFAT1 group. In Colo680N cell, division time in NC group was (1 532±53) min, significantly longer than (1 290±30) min in shFAT1 group ( P <0.05). Knockdown of FAT1 promoted G1-to S-phase transition and resulted in the upregulation of CDK4/CDK6/CCND1. Conclusion: FAT1 inhibits the proliferation and G1-to S-phase transition of ESCC cells through regulating the protein expression of CDK4/CDK6/CCND1 complex.

α-Chymotrypsin (α-CT) and trypsin are important components of the enzymatic barrier. They could degrade the therapeutic proteins and peptides, inhibit their activity consequently, and thereby reduce their oral bioavailability. Acidic agents, as one type of indirect protease inhibitors, have shown proof of concept in clinical trials. We report here the inactivated proteases due to acid influence can be reactivated immediately by environmental pH recovery regardless of how long the inactivation last. To keep the inactivation time of proteases for 4-5 h, we designed and prepared a sustained-release tablet containing citric acid (CA) which can effectively reduce the pH below 5.0 and maintain it for 5 h in the dissolution-reaction medium. The activity of α-CT and trypsin was quantified by analyzing the residual amount of their respective substrates BTEE and TAME. More than 80% of the substrates were survived in 5.0 h of incubation, whereas the common tablet inhibited the proteases activity for only two hours in the same experimental medium. It indicates that the sustained-release tablet loaded with CA can efficiently inhibit the α-CT and trypsin activity longer than the common tablet. The results will be beneficial for designing and formulating the peroral administration of peptide and protein drugs.

The purpose of this study was to explore the value of two-dimensional ShearWave ™ Elastography (2D-SWE) on quantitatively evaluating the change of the content of collagen fibres in penis. Twenty male Sprague Dawley rats were divided into the pre-sexual maturity group (Group 1) and the sexual decline group (Group 2) according to age. The ultrafast ultrasound device Aixplorer ® (SuperSonic Imagine, Aix-en-Provence, France) was used for 2D-SWE imaging of penis, and the measurement index was shear wave stiffness (SWS). The immunohistochemistry was used to analyse the content of collagen fibres in penis, and the measurement index was positive area percentage (PAP). The differences of SWS between the two groups and PAP between the two groups were analysed. SWS of Group 1 and Group 2 was 10.18 ± 1.09 and 8.02 ± 1.34 kPa, and SWS of Group 2 was significantly lower than Group 1 (p < .01). PAP of Group 1 and Group 2 was 4.83 ± 3.61% and 16.41 ± 10.02%, and PAP of Group 2 was significantly higher than Group 1 (p < .01). Our results indicate that when the content of collagen fibres changes, SWS of penis measured with 2D-SWE would change significantly as well. Two-dimensional SWE can be used to quantitatively evaluate the change of the content of collagen fibres in penis., (© 2016 Blackwell Verlag GmbH.)

Viruses have evolved to be outstandingly efficient at gene delivery, but their use as vectors is limited by safety risks. Inspired by the structure of viruses, we constructed a virus-mimicking vector (denoted as TR4@siRNA@Tf NCs) with virus-like architecture and infection properties. Composed of a hydrophilic peptide, an aggregation-induced emission (AIE) luminogen, and a lipophilic tail, TR4 imitates the viral capsid and endows the vector with AIE properties as well as efficient siRNA compaction. The outer glycoprotein transferrin (Tf) mimics the viral envelope protein and endows the vector with reduced cytotoxicity as well as enhanced targeting capability. Because of the strong interaction between Tf and transferrin receptors on the cell surface, the Tf coating can accelerate the intracellular release of siRNA into the cytosol. Tf and TR4 are eventually cycled back to the cell membrane. Our results confirmed that the constructed siRNA@TR4@Tf NCs show a high siRNA silencing efficiency of 85% with significantly reduced cytotoxicity. These NCs have comparable transfection ability to natural viruses while avoiding the toxicity issues associated with typical nonviral vectors. Therefore, this proposed virus-like siRNA vector, which integrates the advantages of both viral and nonviral vectors, should find many potential applications in gene therapy.

The aim of this study was to investigate the feasibility of two-dimensional-ShearWave™ Elastography (2D-SWE) on evaluating the change of tissue structure of penis. Twenty healthy male Sprague Dawley rats were divided into penis-developed group (PDG, 52 weeks) and penis-underdeveloped group (PUDG, 5 weeks). The ultrafast ultrasound device-Aixplorer® (SuperSonic Imagine) was used for 2D-SWE imaging of the penis, the measurement index was shear wave stiffness (SWS, kPa). All rat penises were cut off immediately after ultrasonic examination. After paraffin embedding, slicing and hematoxylin-eosin staining, the tissue structure of the penis was observed under light microscope. SWS of all rat penises were measured successfully. The results showed that SWS of PDG was significantly lower than PUDG (P=0.008). At the same time, the pathological results found that there were significant differences in the tissue structures (sinusoids, smooth muscle cells and fibrocytes) of the penises between the two groups. These results suggest that there are significant differences in SWS between different tissue structures of penis. 2D-SWE is expected to be used on the etiological diagnosis of erectile dysfunction by serving as a new noninvasive method of evaluating the change of tissue structure of penis.

Context 3,4-Oxo-isopropylidene-shikimic acid (ISA) is an analog of shikimic acid (SA). SA is extracted from the dry fruit of Illicium verum Hook. f. (Magnoliaceae), which has been used for treating stomachaches, skin inflammation and rheumatic pain. Objective To investigate the anti-inflammatory, analgesic and antioxidant activities of ISA. Materials and methods Analgesic and anti-inflammatory activities of ISA were evaluated using writhing, hot plate, xylene-induced ear oedema, carrageenan-induced paw oedema and cotton pellets-induced granuloma test, meanwhile the prostaglandin E2 (PGE2) and malondialdehyde (MDA) levels were assessed in the oedema paw tissue. ISA (60, 120 and 240 mg/kg in mice model and 50, 120 and 200 mg/kg in rat model) was administered orally, 30 min before induction of inflammation/pain. Additionally, ISA was administered for 12 d in rats from the day of cotton pellet implantation. The active oxygen species scavenging potencies of ISA (10(-3)-10(-5) M) were evaluated by the electron spin resonance spin-trapping technique. Results ISA caused a reduction of inflammation induced by xylene (18.1-31.4%), carrageenan (7.8-51.0%) and cotton pellets (11.4-24.0%). Furthermore, ISA decreased the production of PGE2 and MDA in the rat paw tissue by 1.0-15.6% and 6.3-27.6%, respectively. ISA also reduced pain induced by acetic acid (15.6-48.9%) and hot plate (10.5-28.5%). Finally, ISA exhibited moderate antioxidant activity by scavenging the superoxide radical and hydroxyl radical with IC50 values of 0.214 and 0.450 μg/mL, respectively. Discussion and conclusion Our findings confirmed the anti-inflammatory, analgesic and antioxidant activities of ISA.

Catalase is a promising therapeutic enzyme; however, it carries risks of inactivation and rapid degradation when it is used in practical bioprocess, such as delivery in vivo. To overcome the issue, we made catalase-only nanoparticles using shear stress alone at a moderate shear rate of 217s(-1) in a coaxial cylinder flow cell. Properties of nanoparticles, including particle size, polydispersity index and zeta potential, were characterized. The conformational changes of pre- and post-sheared catalase were determined using spectroscopy techniques. The results indicated that the conformational changes of catalase and reduction in α-helical content caused by shear alone were less significant than that by desolvation method. Catalase-only nanoparticles prepared by single shear retained over 90% of its initial activity when compared with the native catalase. Catalase nanoparticles lost only 20% of the activity when stored in phosphate buffer solution for 72h at 4°C, whereas native catalase lost 53% under the same condition. Especially, the activity of nanogranulated catalase was decreased only slightly in the simulated intestinal fluid containing α-chymotrypsin during 4h incubation at 37°C, implying that the catalase nanoparticle was more resistant to the degradation of proteases than native catalase molecules. Overall, catalase-only nanoparticles offered a great potential to stabilize enzymes for various pharmaceutical applications., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The development of multidrug resistance (MDR) is the major obstacle in the chemotherapy of breast cancer, and it restricts the application of antitumor drugs in the clinic. Therefore it is urgent to search for ways to reverse MDR and restore sensitivity to chemotherapeutics in breast carcinoma. Currently, histone deacetylase inhibitors (HDACIs) offer a promising strategy for tumor therapy as the effective anticancer drugs. Based on the potential resistant target of nucleophosmin (NPM), the purpose of this study was to explore the reversal effect of a new synthetic histone deacetylase inhibitor, FA17, on MDR in methotrexate-resistant breast cancer cells (MCF-7/MTX) and xenograft tumors. It was shown that the abnormal expression of NPM induced MDR and inhibited downstream mitochondrial apoptotic pathway by activating PI3K/Akt signaling pathway in MCF-7/MTX cells. The reversal effect and molecular mechanism of FA17 were investigated both in vitro and in vivo. We found that FA17 could significantly reverse resistance and sensitize MCF-7/MTX cells to methotrexate. FA17 obviously enhanced resistant cell apoptosis, inhibited expressions of NPM and efflux transporters. Additionally, FA17 could reverse MDR via inactivating PI3K/Akt pathway and accelerating mitochondrial apoptotic pathway both in MCF-7/MTX cells and in xenograft tumors. Taken together, the novel histone deacetylase inhibitor could effectively reverse drug resistance due to suppressing the activity of NPM and drug efflux pumps by PI3K/Akt and mitochondrial apoptotic pathway. The above not only indicated the potential applied value of FA17 in reversing MDR and enhancing the sensitivity of chemotherapy, but also confirmed the role of NPM in the development of MDR in breast cancer.

3D printing technology has attracted much attention due to its high potential in scientific and industrial applications. As an outstanding 3D printing technology, two-photon polymerization (TPP) microfabrication has been applied in the fields of micro/nanophotonics, micro-electromechanical systems, microfluidics, biomedical implants and microdevices. In particular, TPP microfabrication is very useful in tissue engineering and drug delivery due to its powerful fabrication capability for precise microstructures with high spatial resolution on both the microscopic and the nanometric scale. The design and fabrication of 3D hydrogels widely used in tissue engineering and drug delivery has been an important research area of TPP microfabrication. The resolution is a key parameter for 3D hydrogels to simulate the native 3D environment in which the cells reside and the drug is controlled to release with optimal temporal and spatial distribution in vitro and in vivo. The resolution of 3D hydrogels largely depends on the efficiency of TPP initiators. In this paper, we will review the widely used photoresists, the development of TPP photoinitiators, the strategies for improving the resolution and the microfabrication of 3D hydrogels.

Objective: To evaluate the feasibility of measuring the stiffness of corpus cavernosum penis (CCP) with ShearWave™ Elastography (SWE; SuperSonic Imagine, Aix-en-Provence, France)., Methods: 40 healthy volunteers with ages ranging from 19 to 81 years (mean, 36 years; standard deviation, 17 years) were selected in this study. The ultrafast ultrasound device Aixplorer(®) (SuperSonic Imagine) was used for the research and the probe selected was SuperLinear™ SL15-4 (SuperSonic Imagine). The shear wave stiffness (SWS) of CCP was measured using SWE images. The measurement indexes of SWS included (1) SWS of CCP measured in the transverse section (SWS-T), (2) SWS of CCP measured in the longitudinal section (SWS-L) and (3) mean of SWS-T and SWS-L (SWS-M). The interval between hormone test and SWE examination of each subject was less than 7 days. The paired t-test was used to analyse the differences between SWS-T and SWS-L. The Pearson correlation was used to analyse the correlation of SWS of CCP with age as well as with sex hormone levels., Results: There was no significant difference between SWS-T and SWS-L (p > 0.05). SWS (SWS-T, SWS-L, SWS-M) was negatively correlated with age and oestradiol value, and SWS (SWS-T, SWS-L, SWS-M) was positively correlated with testosterone value., Conclusion: SWE could serve as a new non-invasive method of evaluating the stiffness of CCP., Advances in Knowledge: It is the first time that we have discussed the feasibility of measuring the stiffness of CCP with SWE and analysed the correlation of SWS of CCP with age as well as with sex hormone levels.

Purpose: Smooth muscle cells (SMCs) of cavernosum play an important role in erection. It is of great significance to quantitatively analyze the level of SMCs in penis. In this study, we investigated the feasibility of shear wave elastography (SWE) on evaluating the level of SMCs in penis quantitatively., Materials and Methods: Twenty healthy male rats were selected. The SWE imaging of penis was carried out and then immunohistochemistry analysis of penis was performed to analyze the expression of alpha smooth muscle actin in penis. The measurement index of SWE examination was tissue stiffness (TS). The measurement index of immunohistochemistry analysis was positive area percentage of alpha smooth muscle actin (AP)., Results: Sixty sets of data of TS and AP were obtained. The results showed that TS was significantly correlated with AP and the correlation coefficient was -0.618 (p < 0.001). The result of TS had been plotted against the AP measurements. The relation between the two results has been fitted with quadric curve; the goodness-of-fit index was 0.364 (p < 0.001)., Conclusions: The level of SMCs in penis was successfully quantified in vivo with SWE. SWE can be used clinically for evaluating the level of SMCs in penis quantitatively.

Purpose: To evaluate diagnostic performance of acoustic radiation force impulse (ARFI) technology for solid breast masses with different sizes and determine which features are most efficient., Materials and Methods: 271 solid breast masses in 242 women were examined with ARFI, and their shear wave velocities (SWVs), Virtual Touch tissue imaging (VTI) patterns, and area ratios (ARs) were measured and compared with their histopathological outcomes. Receiver operating characteristic curves (ROC) were calculated to assess diagnostic performance of ARFI for small masses (6-14 mm) and big masses (15-30 mm)., Results: SWV of mass was shown to be positively associated with mass size (P < 0.001). For small masses, area under ROC (Az) of AR was larger than that of SWV (P < 0.001) and VTI pattern (P < 0.001); no significant difference was found between Az of SWV and that of VTI pattern (P = 0.906). For big masses, Az of VTI pattern was less than that of SWV (P = 0.008) and AR (P = 0.002); no significant difference was identified between Az of SWV and that of AR (P = 0.584)., Conclusions: For big masses, SWV and AR are both efficient measures; nevertheless, for small masses, AR seems to be the best feature.

Scutellarin (SG) and its aglycone, Scutellarein (S), are flavonoids of therapeutic cardiocerebrovascular disease. SG was hydrolyzed by bacterial enzyme into S which was absorbed in the intestine. The aim of this study was to determine the effects of the microflora in the intestinal lumen and the efflux transporter of intestinal epithelial cells on the absorption process of SG and S. After oral administration of antibiotics in Sprague-Dawley rats, the reduced bacterial enzyme formation significantly hinders the absorption of SG, whereas scarcely that of S. The absorption study in situ single-pass intestinal perfusion revealed that S could be absorbed throughout the intestine of rats. The effective intestinal permeability of S in the jejunum was much lower than in the other sections of the GI tract. The efflux transporter promoted SG secretion into lumen from enterocytes, which hindered the absorption of both SG and S into the bloodstream. The efflux transporter protein inhibitor (verapamil, probenecid and reserpine) remarkably enhanced the absorption of S and the bioconversion of S into SG in both the rat intestine and Caco-2-monolayer models., (Copyright © 2014 John Wiley & Sons, Ltd.)

Background: Breast cancer is a common malignant tumor which affects health of women and multidrug resistance (MDR) is one of the main factors leading to failure of chemotherapy. This study was conducted to establish paclitaxel-resistant breast cancer cell line and nude mice models to explore underlying mechanisms of MDR., Methods: The breast cancer drug-sensitive cell line MCF-7 (MCF-7/S) was exposed in stepwise escalating paclitaxel (TAX) to induce a resistant cell line MCF-7/TAX. Cell sensitivity to drugs and growth curves were measured by MTT assay. Changes of cell morphology and ultrastructure were examined by optical and electron microscopy. The cell cycle distribution was determined by flow cytometry. Furthermore, expression of proteins related to breast cancer occurrence and MDR was tested by immunocytochemistry. In Vivo, nude mice were injected with MCF-7/S and MCF-7/TAX cells and weights and tumor sizes were observed after paclitaxel treatment. In addition, proteins involved breast cancer and MDR were detected by immunohistochemistry., Results: Compared to MCF-7/S, MCF-7/TAX cells had a higher resistance to paclitaxel, cross-resistance and prolonged doubling time. Moreover, MCF-7/TAX showed obvious alterations of ultrastructure. Estrogen receptor (ER) expression was low in drug resistant cells and tumors while expression of human epidermal growth factor receptor 2 (HER2) and Ki-67 was up-regulated. P-glycoprotein (P-gp), lung resistance-related protein (LRP) and glutathione-S-transferase-π (GST-π) involved in the MDR phenotype of resistant cells and tumors were all overexpressed., Conclusion: The underlying MDR mechanism of breast cancer may involve increased expression of P-gp, LRP and GST-π.

A series of C(2v) symmetrical two-photon absorption compounds with anthracene core, 2,7-bis[2-(4-substituted phenyl)-vinyl]-9,10-dipentyloxyanthracenes designated as I, II and III (the substituted groups at the 4-position of phenyl of I, II and III were dimethylamino, methyl and cyano, respectively) were designed and synthesized as initiators in two-photon induced polymerization (TPIP). The anthracene ring was modified by linking vinylphenyl groups to the 2,7-position to extend conjugation system length and two pentyloxy groups to the 9,10-position to serve as electronic donors. Two-photon absorption cross section of I was around 300 GM, which was much larger than the 10 GM of II and 29 GM of III at 800 nm. I of 0.18% molar ratio in resin composed of methacrylic acid and dipentaerythritol hexaacrylate exhibited a dramatically low threshold of 0.64 mW compared with commercial photoinitiator benzil at a scanning speed 10 μm s(-1). Moreover, the threshold of photoinitiator I was only increased to 2.53 mW at a scanning speed of 1000 μm s(-1). The dependency of threshold on the concentration and exposure time was in accordance with theoretical calculation. Finally, a reasonable mechanism of the two-photon initiating process was proposed. This study provides good prospects for developing low threshold photoinitiator in TPIP.

In our previous work, a new kind of pH-sensitive hydrogel based on poly (lactic acid) (PLA), methoxyl poly (ethylene glycol) (MPEG) and itaconic acid (IA) was prepared by heat-initiated free radical polymerization without any organic solvent. For further application, the safety of prepared copolymers and hydrogels was evaluated in vitro and in vivo in this paper. In vitro toxicity evaluation of MPEG-PLA-AC (PLE-AC) copolymers included hemolytic test and cytotoxicity which were evaluated by cell viability assay using HEK293 cells. In vivo acute toxicity tests and histopathological study of PLE-AC copolymers were carried out on BALB/c mice which were administrated copolymers (1 g/kg b.w.) intravenously. In acute toxicity test, the mice were observed continuously for 7 days, their body weight obtained everyday, at last the mice were sacrificed for the following study: the blood of the mice was assigned for blood chemistry and routine analysis, the heart, liver, spleen, lung, and kidneys were used for histopathological study. In acute oral toxicity test, mice were orally administered with a total 15 g/kg body weight (b.w.) of P(LE-IA-MEG) hydrogels, and were observed continuously for 14 days. For histopathologic study, samples including heart, liver, lung, kidneys, spleen, stomach, and intestine, were histochemically prepared and stained with hematoxylin-eosin for histopathologic examination. All results indicated that the PLE-AC copolymers and pH-sensitive hydrogels were non-toxic. Therefore it might be used as a safe candidate for drug delivery system., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Background: 3,4-Oxo-isopropylidene-shikimic acid (ISA) is a derivative of shikimic acid (SA). SA is extracted from Illicium verum Hook.fil., which has been used in traditional Chinese medicine and used for treating vomiting, stomach aches, insomnia, skin inflammation, and rheumatic pain., Aims: To investigate the effects and the protective mechanism of 3,4-oxo-isopropylidene-shikimic acid on experimental colitis model induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS) in rats., Methods: Colitis in rats was induced by colonic administration with TNBS. ISA (50, 100, and 200 mg/kg) was administered for 12 days to experimental colitis rats. The inflammatory degree was assessed by macroscopic damage score, colon weight/length ratios (mg/cm), and myeloperoxidase (MPO) activity. Malondialdehyde (MDA), glutathione (GSH), and nitric oxide (NO) levels, and superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), inducible nitric oxide synthase (iNOS) activities were measured with biochemical methods., Results: ISA significantly ameliorated macroscopic damage, reduced colon weight/length ratios and the activity of MPO, depressed MDA and NO levels and iNOS activity, and enhanced GSH level, and GSH-Px and SOD activities in the colon tissues of experimental colitis in a dose-dependent manner. Moreover, the effect of ISA (200 mg/kg) was as effective as sulfasalazine (500 mg/kg)., Conclusions: The findings of this study demonstrate the protective effect of ISA on experimental colitis, probably due to an antioxidant action.

Aim: To study the metabolic and pharmacokinetic profile of scutellarin, an active component from the medical plant Erigeron breviscapus (Vant) Hand-Mazz, and to investigate the mechanisms underlying the low bioavailability of scutellarin though oral or intravenous administration in rats., Methods: HPLC method was developed for simultaneous detection of scutellarin and scutellarein (the aglycone of scutellarin) in rat plasma, urine and feces. The in vitro metabolic stability study was carried out in rat liver microsomes from different genders., Results: After a single oral dose of scutellarin (400 mg/kg), the plasma concentrations of scutellarin and scutellarein in female rats were significantly higher than in male ones. Between the female and male rats, significant differences in AUC, t(max2) and C(max2) for scutellarin were found. The pharmacokinetic parameters of scutellarin in the urine also showed significant gender differences. After a single oral dose of scutellarin (400 mg/kg), the total percentage excretion of scutellarein in male and female rats was 16.5% and 8.61%, respectively. The total percentage excretion of scutellarin and scutellarein in the feces was higher with oral administration than with intravenous administration. The in vitro t(1/2) and CL(int) value for scutellarin in male rats was significantly higher than that in female rats., Conclusion: The results suggest that a large amount of ingested scutellarin was metabolized into scutellarein in the gastrointestinal tract and then excreted with the feces, leading to the extremely low oral bioavailability of scutellarin. The gender differences of pharmacokinetic parameters of scutellarin and scutellarein are due to the higher CL(int) and lower absorption in male rats.

Objective: To validate a high performance liquid chromatography (HPLC) method for serum teicoplanin measurement and use the method for clinical monitoring of teicoplanin levels to analyze the clinical application of teicoplanin., Methods: 55 patient profiles were collected and analyzed for the clinical teicoplanin application. 10 critically ill patients of the 55 cases were monitored for teicoplanin trough concentration using the HPLC method., Results: The modified HPLC method exhibited excellent linearity, with correlation coefficient r = 0.9995. The intra-day and inter-day coefficients of variation were less than 10%. The lower limit of detection of teicoplanin was 5.63 mg/l. The recovery of teicoplanin was above 90%. Of the 55 patients in this study, there were 42 patients without load-dosing. There were only 29 patients treated with teicoplanin documented Gram-positive infections by etiological diagnoses. In the 10 patients with teicoplanin serum trough concentration monitoring, all cases received a loading dose of 400 mg every 12 h for 3 doses, and the mean trough concentration of teicoplanin was 10.82 ± 4.51 mg/l. The mean trough levels were 13.04 ± 6.23 mg/l in 4 patients with microbiological eradication and improvement of symptoms of diseases and 9.34 ± 2.61 mg/l in 6 patients with persistence of previous clinical infectious symptoms, respectively., Conclusion: The modified HPLC method is robust, highly reproducible and suited to monitor the concentration of teicoplanin. In critically ill Chinese patients, we should consider more appropriate loading doses and evaluate the relationship between teicoplanin trough concentration and the efficacy using microbiological and clinical parameters.

Objective: To investigate the absorption and transepithelial transport characteristics of scutellarin and scutellarein in the human colonic adenocarcinoma cell (Caco-2) monolayer model. The influence factors on these two compounds' absorption were investigated, such as buffer solution, duration of culture, and inhibitors of multidrug resistance-associated protein 2 (MRP(2)), breast cancer drug resistance protein (BCRP) and P-glycoprotein (P-gp)., Methods: By using Caco-2 monolayer as an intestinal epithelial cell model, the transport process was studied from apical (AP) side to basolateral (BL) side or from BL to AP. The two compounds were determined by high-performance liquid chromatography coupled with diode-array-detector detection. Transport parameters and apparent permeability coeffients (P(app)) were calculated., Results: The P(app) values of scutellarin and scutellarein were different in two buffer solutions, respectively. In phosphate buffered saline, scutellarin had no absorption from AP to BL, while its P(app) value was 0.74×10(-6) to 1.58×10(-6) cm/s from BL to AP. The P(app) values of scutellarein were 4.33×10(-6) to 6.79×10(-6) cm/s and 1.32×10(-6) to 2.56×10(-6) cm/s from AP to BL and from BL to AP, respectively. The P(app) value gradually decreased with time. The absorption of scutellarein was better than that of scutellarin. The scutellarin absorption was improved by verapamil, MK-571 and reserpine. The scutellarein absorption was improved by verapamil whereas its excretion was improved by MK-571., Conclusion: Absorption of scutellarin is difficult in Caco-2 monolayer cells, which contributes to its low bioavailability. Scutellarein absorption is better than scutellarin absorption. Scutellarein transepithelial transport is passive diffusion. The inhibitor of P-gp can improve scutellarin and scutellarein transportation. The inhibitors of MRP(2) and BCRP can promote transportation of scutellarin. The inhibitor of MRP(2) can promote efflux of scutellarein. The multidrug resistance-associated protein may be the second reason for low bioavailability of scutellarin.

Objective: To study the method for synthesis of 2-hydroxyl-5- butyramidobenzoic acid and test its effect on acetic acid-induced colitis in rats., Methods: 2-hydroxyl-5-butyramidobenzoic acid was synthesized from 5-aminosalicylic acid and butyric acid by amidation, esterification and hydrolization. The effect of 2-hydroxyl-5-butyramidobenzoic acid on acetic acid enema-induced colitis in rats was investigated., Results: The structure of 2-hydroxyl-5-butyramidobenzoic acid was identified by IR and 1H-NMR. After treatment with acetic acid, the colon mucosal damage index (CMDI), fecal occult blood (OB) test, and activity of myelperoxidase (MPO) increased significantly in the rats as compared to the control levels. 2-hydroxyl-5- butyramidobenzoic acid obviously reduced the CMDI and OB, and reduced the level of MPO in the rats with colitis., Conclusion: The synthesis of 2-hydroxyl-5-butyramidobenzoic acid requires only mild conditions with simple procedures, and the synthesized 2-hydroxyl-5-butyramidobenzoic acid shows obvious therapeutic effects on mucosal damage of in rats with acetic acid-induced colitis.

Objective: To investigate the ultrasonographic indexes in the evaluation of complete penile erection after oral administration of sildenafil citrate in men with normal erectile function., Methods: The subjects lay supine, with the penis raised upwards, its back clinging to the abdomen. The probe was placed at the base of the ventral side of the penis for longitudinal and transverse section scanning. Observations were made on the corpus cavernosum, deep artery and deep dorsal vein of the penis at the time of flaccidity and complete erection after oral administration of sildenafil citrate, respectively., Results: The examinations were acceptable to all the subjects both physically and psychologically, and all were completed successfully with no complications. Compared with the flaccid state of the penis, obvious changes were observed in the state of complete erection, including marked increases in the diameter of the corpus cavernosum ([18.57 +/- 2.50] mm, increased by [106.8 +/- 62.1]%), the inside diameter of the deep artery ([1.18 +/- 0.26] mm, increased by [54.9 +/- 29.0]%), the peak systolic velocity ([32.5 +/- 10.7] cm/s, increased by [209.3 +/- 112.9]%), and the systolic acceleration ([5.71 +/- 2.71] cm/s2, increased by [179.3 +/- 138.2]%)., Conclusion: Oral administration of sildenafil citrate followed by ultrasonography is a new approach to the objective evaluation of penile erection, characterized by convenience, safety, non-invasiveness, non-complication, easy acceptability and easy clinical application.