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Background The XRCC2 gene plays an important role in the homologous recombination repair of DNA double strand breaks. Functional single nucleotide polymorphisms (SNPs) of XRCC2 may alter DNA repair capacity and affect cancer susceptibility. This study aims to evaluate the association between five tagSNPs in XRCC2 and breast cancer susceptibility in Han women of northwest China. Methods A total of 514 histopathologically confirmed breast cancer patients and 1028 region- and age-matched cancer-free controls provided blood samples for analysis of SNP genotypes in this case-control study using a QuantStudio™ 12K Flex Real-Time PCR System. Results After adjusting covariates, 2 SNPs in XRCC2 (rs3218536 and rs6964582) showed significant associations with the risk of breast cancer. In haplotype analysis, CGTTC haplotype conferred an increased risk of breast cancer(P=5.83×10-3), whereas TGTTA haplotype was associated with a decreased risk of breast cancer(P=1.17×10-3). Significant associations were shown between CGTTA, CCTTA haplotypes of XRCC2 and Her-2 statuses(P=2.15×10-3; P=4.06×10-3, respectively). Interaction analysis showed that the three-loci model (rs3218438, rs3218536 and rs6964582) was the best with the maximal testing balance accuracy of 0.6597, and the maximal 100% cross-validation consistency (P=0.001). Conclusion These results indicate that XRCC2 gene polymorphisms may affect the risk of breast cancer and show that some SNPs and haplotypes in XRCC2 are associated with breast cancer characteristics in the Han population of northwest China.

Cobalt nanowires and cobalt particles are introduced into CoAl-LDHs@Fe3O4, and the effect of the former is better in the application of electro-Fenton process.

A targeted composite polysaccharide drug-loaded gel was obtained and characterized. It displayed potent anti-tumor activity via specific binding between the folate in the gel and the folate receptors in the cell membrane.

Porcine-induced pluripotent stem cells (piPSCs) are of great significance to animal breeding and human medicine; however, an important problem is that the maintenance of piPSCs mainly depends on exogenous expression of pluripotent transcription factors (TFs), and germline transmission-competent piPSCs have not yet been successfully established. In this study, we explore the defect of epigenetic reprogramming during piPSCs formation, including chromatin accessibility, DNA methylation, and imprinted gene expression, with high-throughput sequencing (ATAC-seq, WGBS, RNA-seq, and Re-seq) methods. We found the somatic features were successfully silenced by connecting closed chromatin loci with downregulated genes, while DNA methylation has limited effects on somatic silence. However, the incomplete chromatin remodeling and DNA demethylation in pluripotency genes hinder pluripotent activation, resulting in the low expression of endogenous pluripotency genes. In addition, the expression of potential imprinted genes was abnormal, and many allelic-biased expressed genes in porcine embryonic fibroblasts (PEFs) were erased, accompanied by establishment of new allelic-biased expressed genes in piPSCs. This study reveals the aberrant epigenetic reprogramming during dox-dependent piPSCs formation, which lays the foundation for research of porcine-iPSC reprogramming and genome imprinting.

Drawing an instructive point on the correlation between Se content and anti-tumor effects is helpful to develop Se-polysaccharides with potential anti-tumor activities. In this work, Se content-related anti-tumor activities are assessed in vitro by multiple comparisons among Na2SeO3, Artemisia sphaerocephala polysaccharide (ASP), and selenized ASP (SeASPs, Se contents 4344–13 030 μg g−1) synthesized by a chemical modification method. The results suggest that SeASPs exhibit potent anti-proliferation activities against three kinds of tumor cells by inducing apoptosis and cell cycle arrest, which is positively correlated to Se content. Meanwhile, SeASPs display low cytotoxicity against normal cells as compared with Na2SeO3 and 5-FU. A mitochondrial membrane potential assay and western blotting analysis suggest that the SeASPs induce HepG2 cell apoptosis via mitochondrial and death receptor pathways, which is confirmed by the reduced mitochondrial membrane potential, upregulated Bax/Bcl-2 ratio, promoted Cyt C release, and increased expression level of caspase-3/-9/-8. In an in vivo anti-tumor assay, SeASP with a high Se content (13 030 μg g−1) also obviously inhibits H22 tumor growth in a dose-dependent manner, and a tumor suppression rate of 45.10% is observed. In addition, the results of ELISA analysis suggest that SeASPs obviously increase the concentration of serum NO, cytokines (IL-1β, IL-6, TNF-α), and Ig-G in a dose-dependent manner as compared with the control and ASP group. It could be concluded that adjusting the Se content might be an effective approach to improve the anti-tumor activities of Se-polysaccharides.

In this paper, selenized Artemisia sphaerocephala polysaccharides (SePAS) were obtained through employing N-methyl-2-pyrrolidone hydrosulfate as catalyst, which showed a maximum Se content enhanced to 8744 μg/g. FT-IR, 1D/2D NMR, X-ray photoelectron spectroscopy (XPS) and size-exclusion chromatograph analysis exhibited that Se had been successfully introduced into PAS and existed in the form of selenate group (Se4+) with the substitution position at C-6. Furthermore, immunostimulating assays indicated that SePAS with high Se content exhibited stronger immunomodulatory activities by upregulated the phosphorylation level of ERK, JNK and p38, thus enhancing RAW264.7 cells proliferation, phagocytosis, levels of interleukin-6, nitric oxide, tumor necrosis factor and interleukin-1β. The current outcome suggested that Se content might be a critical factor affecting the immunomodulatory effects of selenized PAS on macrophage RAW264.7.

Interventional embolization and minimally invasive thermal ablation are common clinical methods for treatment of unresectable solid tumors, but they both have many insurmountable disadvantages. Inspired by pH-responsive drug delivery systems, we report the tumor microenvironment-gelled nanocomposites with poly[(l-glutamic acid

Heterogeneous electro-Fenton is one of the promising technologies to degrade refractory organic phosphonates. In this work, CoNWs@CoAl-LDHs/Fe

The activity of AMP-activated protein kinase α (AMPKα) is reduced in type 2 diabetes, and type 2 diabetes is associated with muscular atrophy. To date, there is little known about the mechanism by which free fatty acid (FFA) participates in muscular impairment. The purpose of the present study was to explore whether FFA damages myogenesis through the AMPKα-histone deacetylase 4 (HDAC4)-microRNA 206 (miR-206) pathway. The results showed that 1 mM FFA produced lipid accumulation, significantly impaired the insulin signaling pathway, and decreased the myogenic differentiation of C2C12 myoblast cells. FFA reduced the LKB1-AMPKα pathway, and the activation of AMPKα rescued the myogenic impairment caused by FFA (P

Inspired by the mussel foot protein and chitosan-based macromolecular adhesives, a series of chitosan-graft-polypeptides were synthesized by ring-opening polymerization of three N-carboxyanhydrides (NCAs) - 3,4-dihydroxyphenylalanine-N-carboxyanhydride (DOPA-NCA), cysteine-NCA (Cys-NCA) and arginine-NCA (Arg-NCA) - using partial-NH2-protected chitosan as an initiator. These copolymers demonstrated good biodegradability and low cytotoxicity. The results of lap-shear adhesion test showed that the maximum lap-shear adhesion strength on the porcine skin and aluminum sheet were 195.97 ± 21.1 kPa and 3080 ± 320 kPa, respectively, and the maximum tensile adhesion strength on bone was 642.70 ± 61.1 kPa. The rat experiment in vivo showed that these copolymers exhibited good hemostatic performance and can promote the healing of skin wound and bone fracture. It is expected that thesecopolymeric adhesives will have broad applications in hemostasis and soft tissue adhesions.

In spite of carbon ion radiotherapy is a talented modality for malignant tumor patients, the radiation damage of normal tissues adjacent to tumor and the dysfunction of immune system limits therapeutic gain. Protecting immune system against carbon ion radiation-caused damage has the possibility to improve cancer treatment, but it is uncertain whether conventional radioprotective agents play a role in carbon ion radiation. To certify carbon ion caused immune dysfunction and assess the radioprotective effect of melatonin on immune system, animal experiments were performed in radiosensitive BALB/C mice. Here, we observed the bodyweight loss, death and apoptosis, abnormal T-cell distributions in immune system in carbon ion radiated mice. Pretreatment with melatonin could increase the index of thymus and spleen, reduce cell apoptosis in thymus and spleen, and attenuate the carbon ion radiation-caused imbalance of T lymphocytes and disorder of cytokines. These results suggest that melatonin can act as an effective protector against carbon ion radiation-caused immune dysfunction. Furthermore, we also found melatonin restored the activity of the antioxidant enzymes and reduced the level of lipid peroxidation in serum. These data have provided baseline information both for radiation workers and cancer patients to use melatonin as a radioprotector during the carbon ion radiation treatment.

Glucose 6-P dehydrogenase (G6PD) is the first rate-limiting enzyme in pentose phosphate pathway (PPP), and it is proverbial that G6PD is absent in skeletal muscle. However, how and why G6PD is down-regulated during skeletal muscle development is unclear. In this study, we confirmed the expression of G6PD was down-regulated during myogenesis in vitro and in vivo. G6PD was absolutely silent in adult skeletal muscle. Histone H3 acetylation and DNA methylation act together on the expression of G6PD. Neither knock-down of G6PD nor over-expression of G6PD affects myogenic differentiation. Knock-down of G6PD significantly promotes the sensitivity and response of skeletal muscle cells to insulin; over-expression of G6PD significantly injures the sensitivity and response of skeletal muscle cells to insulin. High-fat diet treatment impairs insulin signaling by up-regulating G6PD, and knock-down of G6PD rescues the impaired insulin signaling and glucose uptake caused by high-fat diet treatment. Taken together, this study explored the importance of G6PD deficiency during myogenic differentiation, which provides new sight to treat insulin resistance and type-2 diabetes.

Skeletal muscle is a major organ in animals, which constitutes over 40% of livestock body weight, and plays a critical role in metabolism and homeostasis in an organism. Autophagy and apoptosis are two major processes to determine cell fate. Recently, the importance of autophagy and apoptosis in myogenesis has been identified; however, their crosstalk is not well defined. In this study, we aimed to explore the relationship between apoptosis and autophagy during myogenic differentiation. The results showed that the level of autophagy was consistent with apoptosis during myogenic differentiation. The increased apoptosis activated autophagy, and then autophagy inhibited apoptosis in turn to prevent excessive apoptosis and maintain the stability of cells. The interaction between autophagy and apoptosis determines the balance of cell death and cell survival, allowing the skeletal muscle cells to differentiate normally.

Drawing an instructive point on the correlation between Se content and anti-tumor effects is helpful to develop Se-polysaccharides with potential anti-tumor activities. In this work, Se content-related anti-tumor activities are assessed in vitro by multiple comparisons among Na2SeO3, Artemisia sphaerocephala polysaccharide (ASP), and selenized ASP (SeASPs, Se contents 4344-13 030 μg g-1) synthesized by a chemical modification method. The results suggest that SeASPs exhibit potent anti-proliferation activities against three kinds of tumor cells by inducing apoptosis and cell cycle arrest, which is positively correlated to Se content. Meanwhile, SeASPs display low cytotoxicity against normal cells as compared with Na2SeO3 and 5-FU. A mitochondrial membrane potential assay and western blotting analysis suggest that the SeASPs induce HepG2 cell apoptosis via mitochondrial and death receptor pathways, which is confirmed by the reduced mitochondrial membrane potential, upregulated Bax/Bcl-2 ratio, promoted Cyt C release, and increased expression level of caspase-3/-9/-8. In an in vivo anti-tumor assay, SeASP with a high Se content (13 030 μg g-1) also obviously inhibits H22 tumor growth in a dose-dependent manner, and a tumor suppression rate of 45.10% is observed. In addition, the results of ELISA analysis suggest that SeASPs obviously increase the concentration of serum NO, cytokines (IL-1β, IL-6, TNF-α), and Ig-G in a dose-dependent manner as compared with the control and ASP group. It could be concluded that adjusting the Se content might be an effective approach to improve the anti-tumor activities of Se-polysaccharides.

The National Southwest Associated University (Lianda) was born in Kunming, Yunnan Province and brought the force of the Peking University, Tsinghua University and Nankai University during Sino-Japanese War. As a temporary university living only eight years, it cultivated lots of professionals in all areas during hard years. Lianda provided some unique educational ideas and ideological and political education methods for the higher education.

Ionizing radiation exposure is associated with a risk of cardiac fibrosis; however, the underlying molecular mechanism remains unclear. Growth/differentiation factor-15 (GDF15), a fibroblast factor, is a divergent member of the transforming growth factor β superfamily. Next-generation sequencing analyses has revealed that Gdf15 is increased in cardiac fibroblasts during radiation-induced fibrosis. However, the role of Gdf15 in cardiac fibrosis remains unclear. In this study, we demonstrated that the upregulated expression of GDF15 in newborn rat cardiac fibroblasts and adult rats after irradiation could induce fibrosis, which was confirmed by the increased cell proliferation rate and the increased expression of fibrosis markers (Col1α and αSMA) in newborn rat cardiac fibroblasts after transfection with Gdf15 in vitro. Conversely, the downregulation of GDF15 inhibited cardiac fibrosis, as confirmed by G2/M-cell cycle arrest, suppression of cell proliferation, and low levels of Col1α and αSMA expression. We also found that suppressing the expression of Gdf15 in cardiac fibroblasts could lead to a decrease in CDK1 and inhibit phosphorylation of ERK1/2. Thus, GDF15 might promote cardiac fibroblast fibrosis through the MAPK/ERK1/2 pathway and thus contribute to the pathogenesis of radiation-induced heart disease.

Background Radiation exposure of the thorax is associated with a greatly increased risk of cardiac morbidity and mortality even after several decades of advancement in the field. Although many studies have demonstrated the damaging influence of ionizing radiation on cardiac fibroblast (CF) structure and function, myocardial fibrosis, the molecular mechanism behind this damage is not well understood. miR-21, a small microRNA, promotes the activation of CFs, leading to cardiac fibrosis. miR-21 is overexpressed after irradiation; however, the relationship between increased miR-21 and myocardial fibrosis after irradiation is unclear. This study was conducted to investigate gene expression after radiation-induced CF damage and the role of miR-21 in this process in rats. Methods We sequenced irradiated rat CFs and performed weighted correlation network analysis (WGCNA) combined with differentially expressed gene (DEG) analysis to observe the effect on the expression profile of CF genes after radiation. Results DEG analysis showed that the degree of gene changes increased with the radiation dose. WGCNA revealed three module eigengenes (MEs) associated with 8.5-Gy-radiation—the Yellow, Brown, Blue modules. The three module eigengenes were related to apoptosis, G2/M phase, and cell death and S phase, respectively. By blocking with the cardiac fibrosis miRNA miR-21, we found that miR-21 was associated with G2/M blockade in the cell cycle and was mainly involved in regulating extracellular matrix-related genes, including Grem1, Clu, Gdf15, Ccl7, and Cxcl1. Stem-loop quantitative real-time PCR was performed to verify the expression of these genes. Five genes showed higher expression after 8.5 Gy-radiation in CFs. The target genes of miR-21 predicted online were Gdf15 and Rsad2, which showed much higher expression after treatment with antagomir-miR-21 in 8.5-Gy-irradiated CFs. Thus, miR-21 may play the role of fibrosis and G2/M blockade in regulating Grem1, Clu, Gdf15, Ccl7, Cxcl1, and Rsad2 post-irradiation.

In this study, a sulfated Artemisia sphaerocephala polysaccharide (ASPs) was prepared and its antitumor activity was evaluated in tumor cells and Hepatoma 22 (H22) tumor-bearing mice. In vitro experiments, ASPs significantly inhibited the growth of HepG2 and Hela cells with the IC50 values of 172.03 and 161.42 μg/mL, respectively. Moreover, no direct cytotoxicity against mouse fibroblast L929 normal cells was observed in vitro. After oral administration for 12 days, the tumor growth was significantly suppressed by ASPs at the doses of 200 mg/kg (inhibition rate of 60.85%). Results of tumor histological morphology and cell cycle analysis showed that ASPs could arrest H22 cells at S phase and promote cell apoptosis. Additionally, immunohistochemical analysis demonstrated that ASPs caused the down-regulation of mutant p53 protein expression in a dose-dependent manner. Therefore, these findings proposed new insight into antitumor properties of sulfated polysaccharide as a promising agent in cancer treatment.

Phenol and butanolone catalyzed by different SO3H-functionalized ionic liquids (ILs) for synthesis of raspberry ketone (RK) had been investigated. The influences of different ionic liquids, reaction time, reaction temperature, reactant ratio, the amount of ionic liquid were investigated. The yield of raspberry ketone was 82.5% under the optimum reaction condition. In addition, the ILs (3-sulfo)propyltriamine bisulfate ([TEA-PS][HSO4]) can be recycled up to five consecutive times without loss of activity. This method had the advantages of mild conditions, high product yield, easy to separate from the product, as well as environmentally friendly procedure. At the same time, the possible reaction mechanism was discussed.

A series of hyperbranched, thermo-responsive and mussel-inspired polypeptides were synthesized and used for surgical adhesion, hemostasis and interventional embolization. These polypeptides showed excellent tissue-adhesive properties according to adhesive strength tests on porcine skin and bone in vitro, where the maximum lap-shear adhesion strength on porcine skin was 114.5 kPa and the maximum tensile adhesion strength on bone was 786 kPa. In vivo animal experiments indicated that these polypeptides exhibit superior hemostatic properties and healing effects in skin incisions and osteotomy gap; the skin incision healing and osteotomy gap remodeling were completed in all rats after 14 and 60 days, respectively. In vivo evaluation of the embolization ability of these polypeptides was performed on rabbit kidney models, resulting in successful occlusion of renal arteries, which led to gross ischemic changes in the embolized kidneys up to 16 days. A trial embolization procedure on H22 tumor-bearing rat models also confirmed the gelability of these polypeptides in tumor arteries, which might cause damage to embolized tumors. Therefore, these polypeptides are expected to be good candidates as surgical tissue adhesives, antibleeding materials, and effective embolic materials.

In this study, thermoresponsive and mussel-inspired polypeptides were synthesized using ring-opening polymerization of α-amino acid derivatives of N-carboxyanhydride (NCA). The tissue adhesive properties of these polypeptides were evaluated using in vitro adhesive strength tests on porcine skin and bone. The results indicated that the species of the functional polypeptide side groups and the adhesive temperature have a significant influence on the adhesion strength. The maximum of the lap-shear adhesion strength on porcine skin was 101.2 kPa, and the maximum of tensile adhesion strength on bone was 603 kPa. The in vivo antibleeding activity and tissue adhesive ability were also evaluated using a rat model. These polypeptides exhibited superior hemostatic properties and healing effects in the skin incision and osteotomy gap, and the skin incision healing and osteotomy gap remodeling were completed in all rats after 2–9 weeks. These polypeptides are expected to be good candidates for surgical tissue adhesiv...

In this paper, selenized Artemisia sphaerocephala polysaccharides (SePAS) were obtained through employing N-methyl-2-pyrrolidone hydrosulfate as catalyst, which showed a maximum Se content enhanced to 8744 μg/g. FT-IR, 1D/2D NMR, X-ray photoelectron spectroscopy (XPS) and size-exclusion chromatograph analysis exhibited that Se had been successfully introduced into PAS and existed in the form of selenate group (Se

Bleached palm fiber without lignin, alkalized palm fiber without hemicelluloses and raw windmill palm fiber were prepared. Then, the chemical composition and the mechanical properties of the windmill palm fiber were investigated. Scanning electron microscopy, Fourier transform infrared spectroscopy and Raman microscopy were employed to characterize the structure and chemical composition. A universal material tester, nanoindentation and dynamic mechanical analysis were used to study the mechanical property of these samples. According to the results, bleach treatment removed most of the silica bodies as well as the lignin, smoothed the fiber surfaces and increased the hollowness to 50%. Alkali treatment removed most of the hemicelluloses, increased the surface roughness, and reduced the hollowness to 28%. Alkalized fibers have the highest tensile strength, elongation at break and elastic modulus, with values of 119.37 ± 27.21 MPa, 30.58 ± 5.87% and 10.75 ± 4.30 GPa, respectively. The raw material without treatment has the highest stiffness, while the alkalized samples are the most flexible fibers and sensitive to temperature.

2H-Pyridazino[1,2-a]indazole-1,6,9(11H)-triones were synthesized through one-pot, three-component condesation of aldehydes, maleic hydrazide, and dimedone using a green and inexpensive Bronsted acidic ionic liquid 1-methyl-2-pyrrolidinone hydrosulfate ([Hnmp]HSO4) as catalyst under solvent-free conditions. The method provided several advantages such as milder conditions, shorter reaction time, high yields, and environmentally benign procedure.

Circulating miRNAs presenting in plasma in a stable manner have been demonstrated their potential role as a promising biomarkers in many human diseases, such as Alzheimer’s disease, melanoma and ovarian carcinoma. However, few circulating miRNAs could be used for breast ductal cancer diagnosis. Here, we identified miR-1273g-3p as a biomarker for detecting breast ductal cancer. We detected miR-1273g-3p levels in the plasma of 39 sporadic breast ductal cancer patients and 40 healthy donors by Stem-loop Quantitative Real-time PCR (qRT-PCR). The results showed the plasma miR-1273g-3p level were significantly up-regulated in breast ductal cancer patients compared with healthy donors (p=0.0139). Receiver operating characteristic (ROC) curve also revealed the significantly diagnostic ability of miR-1273g-3p in patients (p=0.0414). In addition, the plasma level of miR-1273g-3p was closely related to IIIB-IIIC TNM stage. We also confirmed the higher expression level of miR-1273g-3p in breast cancer cell lines MCF-7 (4.872±0.537) than normal breast cells (Hs 578Bst). Taken together, miR-1273g-3p could represent as a potential biomarker for early breast ductal cancer diagnosis.

In order to study features of rock–water interaction, a self-developed experimental system called Intelligent Testing System for Water Absorption in Deep Soft Rocks (ITSWADSR) was utilized to analyze the hydrophilic behaviors of natural soft rock at high stress state. Combining X-ray diffraction and mercury injection test, main influencing factors on hydrophilic characteristics were studied. According to the results, it could be concluded as the following: (1) the effective porosity, and the content of illite, illite/smectite formation (S = 5%) and kaolinite have positive correlation with the water absorption capacity of rock; meanwhile, the initial moisture content, fractal dimension of effective pores, illite/smectite formation (S = 30%) and chlorite present negative correlation; (2) among the positive factors, the ascending order is kaolinite, illite/smectite formation (S = 5%) and illite; (3) the descending order among the negative factors are chlorite, illite/smectite formation (S = 30%) and fractal dimension of the effective pores; (4) influence of effective porosity on the pressurized water absorbing capacity of rock is minimal, while it is maximal in the process of no pressurized water absorption. Keywords: Natural soft rock, Water absorption tests, X-ray diffraction, Mercury injection test, Hydrophilic characteristics

A questionnaire survey of breast health. Questionnaire included participant's eating habits, living environment, lifestyle, smoking, physiological state, reproductive condition, past medical history and family history of cancer. (PDF 415 kb)

A series of water absorption tests on dried soft rock have been conducted by the intelligent testing system for water absorption tests in deep soft rock, including tests of water absorption with and without pressure. The results show that the water absorbing capacity of rock with a certain pressure is larger than that of rock without pressure; however, the relationship between the water absorbing percentage and the time can be expressed by w(t) = a(1 − e-bt). In bi-logarithmic coordinates, the hydrophilic relationship with time in tests with pressure could be characterized by linearity, while they present concave or convex in tests without pressure. Based on the hypothesis that each influential factor is irrelevant and they have a linear correlation with the water absorbing capacity, we calculated the weight coefficient of each factor according to experimental results under different conditions. The calculations demonstrate that the effective porosity, content of smectite and kaolinite are all positively correlated with the water absorption capacity of rock; meanwhile, the fractal dimension of the effective pores presents a negative correlation with the water absorption capacity of rock. The water absorption capacity with pressure increases with increasing illite, chlorite and chlorite/smectite formation and a decrease in illite/smectite formation and the fractal dimension of the effective pores, while it is opposite in tests without pressure. The weight coefficient of smectite is smallest among positive factors, and the fractal dimension of the effective pores is the smallest amongst the negative factors. Keywords: Deep soft rock, Water absorption tests, Porosity, Fractal dimension, Clay minerals

ERCC5 plays an important role in DNA damage repair. Mutations in it will lead to DNA repair defects and genomic instability. Its functional single nucleotide polymorphisms (SNPs) may alter DNA repair capacity and affect cancer susceptibility. This study aims to evaluate the association between SNPs in ERCC5 and breast cancer susceptibility in Han women subjects genetically from northwest China. A total of 101 breast cancer patients and 101 healthy controls provided blood samples for analysis of ERCC5 rs17655 and rs751402 genotypes. After adjusting covariates, rs751402 homozygote AA and heterozygote AG were found to confer statistically significant protections (OR 0.052, 95 % CI 0.006–0.411, P = 0.005; OR 0.145, 95 % CI 0.067–0.315, P

Use of microwave radiation is one of the most potential techniques in polysaccharide derivatives synthesis due to its advantages such as higher yields, milder reaction conditions and shorter reaction times. This study was aimed at producing sulfated polysaccharides by microwave irradiation using polar reagents and solvent. Six sulfated Artemisia sphaerocephala polysaccharide derivatives (SPAS) were obtained by using chlorosulfuric acid/pyridine method in the reaction duration range of 15-300 min at a fixed microwave power of 100W. Synthesis of SPAS under microwave filed was highly effective and characterized by time saving and high degrees of substitution (DS). The chemical structure of SPAS was confirmed by FT-IR and 13C NMR that sulfation had occurred and the substitution position was mainly at C-6. Size-exclusion chromatograph combined with multi-angle laser photometer (SEC-MALLS) data indicated that short reaction time minimized acid-catalyzed degradation of polysaccharide chains. AFM observation demonstrated that low-MW derivative exhibited aggregation of polysaccharide chain as irregular spherical lumps. In anti-tumor activity assays, sulfation of PAS significantly improved the capacity to inhibit tumor cells growth by arresting the cell cycle progress in specific phases. It could be concluded that MW and molecular mass distribution had much greater influence on anti-tumor activities of SPAS against human non-small cell lung cancer A549 cells, human hepatocellular carcinoma HepG2 cells and human cervical cancer Hela cells. Microwave-assisted synthesis might possess widespread application in preparation of new polysaccharide derivatives with rich variety of structural features and bioactivities.

Inspired by marine mussel adhesive proteins, polymers with catechol side groups have been extensively explored in industrial and academic research. Here, Pluronic L-31 alcoholate ions were used as the initiator to prepare a series of polypeptide-Pluronic-polypeptide triblock copolymers via ring-opening polymerization of l-DOPA-N-carboxyanhydride (DOPA-NCA), l-arginine-NCA (Arg-NCA), l-cysteine-NCA (Cys-NCA), and ε-N-acryloyl lysine-NCA (Ac-Lys-NCA). These copolymers demonstrated good biodegradability, biocompatibility, and thermoresponsive properties. Adhesion tests using porcine skin and bone as adherends demonstrated lap-shear adhesion strengths up to 106 kPa and tensile adhesion strengths up to 675 kPa. The antibleeding activity and tissue adhesive ability were evaluated using a rat model. These polypeptide-Pluronic copolymer glues showed superior hemostatic properties and superior effects in wound healing and osteotomy gaps. Complete healing of skin incisions and remodeling of osteotomy gaps were observed in all rats after 14 and 60 days, respectively. These copolymers have potential uses as tissue adhesives, antibleeding, and tissue engineering materials.

In this study, a hybrid structure of inversely truncated pyramid-shaped diamond nanopits infilled with gold nanoparticle (Au NP) has been fabricated from a Au film coated single crystal diamond by oxygen plasma etching. Surface enhanced Raman scattering (SERS) performances based on the Au-NP/diamond-pit, using 4-Mercaptopyridine as the probe molecule, show that the hybrid structure could realize a larger SERS enhancement factor compared to the conventional isolated Au NPs. This is attributed to the increased concentration of incident light field on the Au NPs due to the special geometric feature, and the coupling of localized surface plasmon resonance from Au NPs. Taking into account the unique properties of diamond, the diamond-related hybrid structure could be used as a kind of high performance SERS substrate.