A surface-eroding poly(1,3-trimethylene carbonate) coating for magnesium based cardiovascular stents with stable drug release and improved corrosion resistance.

Magnesium alloys with integration of degradability and good mechanical performance are desired for vascular stent application. Drug-eluting coatings may optimize the corrosion profiles of magnesium substrate and reduce the incidence of restenosis simultaneously. In this paper, poly (trimethylene carbonate) (PTMC) with different molecular weight (50,000 g/mol named as PTMC5 and 350,000 g/mol named as PTMC35) was applied as drug-eluting coatings on magnesium alloys. A conventional antiproliferative drug, paclitaxel (PTX), was incorporated in the PTMC coating. The adhesive strength, corrosion behavior, drug release and biocompatibility were investigated. Compared with the PLGA control group, PTMC coating was uniform and gradually degraded from surface to inside, which could provide long-term protection for the magnesium substrate. PTMC35 coated samples exhibited much slower corrosion rate 0.05 µA/cm2 in comparison with 0.11 µA/cm2 and 0.13 µA/cm2 for PLGA and PTMC5 coated counterparts. In addition, PTMC35 coating showed more stable and sustained drug release ability and effectively inhibited the proliferation of human umbilical vein vascular smooth muscle cells. Hemocompatibility test indicated that few platelets were adhered on PTMC5 and PTMC35 coatings. PTMC35 coating, exhibiting surface erosion behavior, stable drug release and good biocompatibility, could be a good candidate as a drug-eluting coating for magnesium-based stent.

Study on the Formation of Glycine by Hydantoin and Its Kinetics.

The preparation of glycine by the hydantoin method is currently a relatively advanced process. The raw materials of this process are nontoxic, the operation process is simple and safe, the side reactions are few, and the yield of glycine is high. The core reaction of the hydantoin method is the hydrolysis of hydantoin. The hydrolysis is divided into two steps: first, hydantoin is hydrolyzed into hydantoin acid, and hydantoin acid is further hydrolyzed into glycine. At a temperature of 423.15 K, a molar ratio of sodium hydroxide to hydantoin of 1:3, and a total reaction time of 6 h, the conversion rate of hydantoin reached 100% and the yield of glycine reached 91%. At the same time, by calculating the hydrolysis kinetic parameters, the reaction was determined to be a first-order series reaction, and a kinetic model was established, which laid the foundation for the development of a green glycine process and a new reactor.

Frequent heteroplasmy and recombination in the mitochondrial genomes of the basidiomycete mushroom Thelephora ganbajun.

In the majority of sexual eukaryotes, the mitochondrial genomes are inherited uniparentally. As a result, individual organisms are homoplasmic, containing mitochondrial DNA (mtDNA) from a single parent. Here we analyzed the mitochondrial genotypes in Clade I of the gourmet mushroom Thelephora ganbajun from its broad geographic distribution range. A total of 299 isolates from 28 geographic locations were sequenced at three mitochondrial loci: the mitochondrial small ribosomal RNA gene, and the cytochrome c oxidase subunits I (COX1) and III (COX3) genes. Quantitative PCR analyses showed that the strains had about 60-160 copies of mitochondrial genomes per cell. Interestingly, while no evidence of heteroplasmy was found at the 12S rRNA gene, 262 of the 299 isolates had clear evidence of heterogeneity at either the COX1 (261 isolates) or COX3 (12 isolates) gene fragments. The COX1 heteroplasmy was characterized by two types of introns residing at different sites of the same region and at different frequencies among the isolates. Allelic association analyses of the observed mitochondrial polymorphic nucleotide sites suggest that mtDNA recombination is common in natural populations of this fungus. Our results contrast the prevailing view that heteroplasmy, if exists, is only transient in basidiomycete fungi.

Serum peroxiredoxin3 is a useful biomarker for early diagnosis and assessemnt of prognosis of hepatocellular carcinoma in Chinese patients.

BACKGROUND: Recently, peroxiredoxin3 (PRDX3) was identified as a novel molecular marker for the progression of hepatocellular carcinoma (HCC). However, its potential clinical application as a serum marker for the early diagnosis and prognosis of HCC has not been investigated. METHODS: PRDX3, alpha-fetaprotein (AFP), and other biochemical parameters were measured in serum samples from 297 Chinese patients, including 96 with HCC, 98 with liver cirrhosis (LC), and 103 healthy controls (HCs). Correlations between serum PRDX3 expression and clinicopathological variables and the relationship between serum PRDX3 expression and prognosis were analyzed. RESULTS: Serum PRDX3 was significantly higher in HCC patients than in the LC and HC groups. The sensitivity and specificity of serum PRDX3 for the diagnosis of HCC were 85.9% and 75.3%, respectively, at a cutoff of 153.26 ng/mL, and the area under the curve was 0.865. Moreover, serum PRDX3 expression was strongly associated with AFP level, tumor diameter, TNM stage, and portal vein invasion. Kaplan-Meier curve analysis revealed that HCC patients with high serum PRDX3 expression had a shorter median survival time than those with low PRDX3 expression. Moreover, serum PRDX3 expression was an independent risk factor for overall survival. The inverse correlation between serum PRDX3 and patient survival remained significant in patients with early-stage HCC and in those with normal serum AFP levels. CONCLUSIONS: Serum PRDX3 can be used as a noninvasive biomarker for the diagnosis and/or prognosis of HCC.

miR-340 reverses cisplatin resistance of hepatocellular carcinoma cell lines by targeting Nrf2-dependent antioxidant pathway.

Many chemotherapeutic agents have been successfully used to treat hepatocellular carcinoma (HCC); however, the development of chemoresistance in liver cancer cells usually results in a relapse and worsening of prognosis. It has been demonstrated that DNA methylation and histone modification play crucial roles in chemotherapy resistance. Currently, extensive research has shown that there is another potential mechanism of gene expression control, which is mediated through the function of short noncoding RNAs, especially for microRNAs (miRNAs), but little is known about their roles in cancer cell drug resistance. In present study, by taking advantage of miRNA effects on the resistance of human hepatocellular carcinoma cells line to cisplatin, it has been demonstrated that miR-340 were significantly downregulated whereas Nrf2 was upregulated in HepG2/ CDDP (cisplatin) cells, compared with parental HepG2 cells. Bioinformatics analysis and luciferase assays of Nrf2-3'-untranslated region-based reporter constructor indicated that Nrf2 was the direct target gene of miR- 340, miR-340 mimics suppressing Nrf2-dependent antioxidant pathway and enhancing the sensitivity of HepG2/ CDDP cells to cisplatin. Interestingly, transfection with miR-340 mimics combined with miR-340 inhibitors reactivated the Nrf2 related pathway and restored the resistance of HepG2/CDDP cells to CDDP. Collectively, the results first suggested that lower expression of miR-340 is involved in the development of CDDP resistance in hepatocellular carcinoma cell line, at least partly due to regulating Nrf2-dependent antioxidant pathway.

[Soft-tissue pyogenic infection in neonates caused by Staphylococcus aureus carrying Panton-Valentine leukocidin genes].

OBJECTIVE: To investigate the pathogen causing soft-tissue pyogenic infection in neonate. METHODS: The isolates of Staphylococcus aureus were obtained from liquor puris and blood by routine method. The Automated Microbiology Analyzer was used for identification and antimicrobial susceptibility test of the isolates. Panton-Valentine leukocidin (PVL) genes were determined by multiplex PCR in the isolates of Staphylococcus aureus. Multilocus sequence typing (MLST) was used to determine the sequence types (STs) of the isolates. The genotypes of SCCmec were also determined by another multiplex PCR in the isolates of methicillin-resistant Staphylococcus aureus (MRSA). RESULTS: In 3 cases of neonate with soft-tissue pyogenic infection, 2 strains of Staphylococcus aureus isolated from liquor puris in 2 cases. 2 strains of Staphylococcus aureus were isolated from liquor puris and blood from another case. All 4 isolates were methicillin-resistant Staphylococcus aureus (MRSA) strains carrying PVL genes. Their SCCmec types were SCCmec IIIA. The STs of 4 isolates were ST88. The antimicrobial-resistance profile of the isolates were the same except erythromycin. CONCLUSION: Soft-tissue pyogenic infection in the 3 neonates was caused by the same clone of MRSA carrying PVL genes.

[Effects of soybean isoflavone on born metabolism and morphology in animal model of osteoporosis rats].

OBJECTIVE: To study the effects of soybean isoflavone (SI) on born metabolism and morphology in animal model of osteoporosis rats. METHODS: All 70 female Sprague-Dawley (SD) rats were randomly divided into 7 groups according to the levels of total cholesterol (TC) in serum: hyper-lipoid group, estrogen group, low-dose SI group, middle-dose SI group, high-dose SI group, sham group and normal control groups. Bilateral ovaries were extirpated except sham and normal control groups. Except the rats in normal control group, the other rats were fed with high fat diet. Body weight was weighted ad unam vice per week. The estrogen, different dose of SI or deionized water were fed with intragastric administration for 12 weeks. Vena caudalis serum were collected after being ovariectomized, administered for 4 w, 8 w and killed. Serum alkaline phosphatase (AKP) activity and bone density were measured etc. RESULTS: To interfere of estrogen and SI might recover AKP enzyme activity after its being ovariectomized. There almost sowed no differences between high dose SI intervention and estrogen on bone density and microstructure. Bone loss due to being ovariectomized was relieved after SI intervention. SI might protect cardiocyte myofilament and mitochondrial ultramicrostructure. There was mirror image in estrogen, high dose SI group resembling the normal control group, and there was obvious damage in hyper-lipoids group. CONCLUSION: There should be effects of high dose SI on bone metabolism and morphology in animal model of osteoporosis rats. Serum AKP enzyme activity and bone density should have significantly recovered, the serum level of calcium and phosphorus were maintained after high dose intervened but no significant effects for low dose of SI.