炭疽芽胞杆菌(Bacillus anthracis)检测质粒的构建及其应用

根据炭疽芽胞杆菌(Bacillus anthracis)毒性质粒pX01和pX02上的2个毒力相关基因cya和capA的序列特点,以pIJ2925为出发载体,采用一步重叠延伸PCR技术(One-step Overlap Extension PCR,简称OOE-PCR)构建了包含cya基因和capA基因保守区DNA片段的炭疽检测质粒pBIB2006。采用复合PCR对模拟炭疽危险品进行分析,结果表明pBIB2006可以为炭疽芽胞杆菌的检测提供准确、安全和方便的阳性参照品,从而为检测炭疽芽胞杆菌和炭疽芽胞杆菌灭活疫苗提供了便利。     

Matrix metalloproteinase-9 induces cardiac fibroblast migration, collagen and cytokine secretion: inhibition by salvianolic acid B from Salvia miltiorrhiza

Cardiac fibroblasts play the key role in cardiac function and matrix metalloproteinases-9 (MMP-9) is a well known contributor to the development of myocardial remodeling. However, the direct regulation of MMP-9 on the function of cardiac fibroblasts and the underlying mechanism are far from elucidation. In the present research, recombinant protein encoding catalytic domain of MMP-9 (MMP-9 CD) was constructed and the function of neonatal cardiac fibroblasts was investigated by cell proliferation assay, migration assay, picrosirius red assay, multiplex cytokine assay and fibroblast phenotype detection. 200 nM MMP-9 CD stimulated cardiac fibroblasts migration (169.4±22.5% versus 100±0%, p<0.01), increased collagen synthesis (1.5±0.2 fold, p<0.05), up-regulated the secretion of ICAM (574.0±40.1 versus 268.5±8.6pg/ml, p<0.01), TNF-α (192.6±11.0 versus 14.4±1.8pg/ml, p<0.001), IL-6 (1500.9±70.2 versus 323.4±40.6pg/ml, p<0.001) and sVCAM-1 (30.3±4.3 versus 7.0±0.1 pg/ml, p<0.05) and down-regulated VEGF (436.5±148.9 versus 1034.3±28.1 pg/ml, p<0.05) significantly with modest effects on proliferation. Accompanying with these regulations, transition of fibroblasts to myofibroblast was confirmed by immunofluorescent stain of α-smooth muscle actin (α-SMA) with MMP-9 CD treatment. Furthermore, salvianolic acid B (SalB) inhibited the effects of MMP-9 CD significantly. In conclusion, our results provide evidence for a direct influence of MMP-9 on cardiac fibroblast migration, collagen and cytokine secretion, which can be attenuated by SalB.     

Combined effects of avasimibe immunotherapy,doxorubicin chemotherapy,and metal–organic frameworks nanoparticles on breast cancer

CD8⁺ T cells play a vital role in cancer immunotherapy and can be shaped by metabolism. Avasimibe is an acyl coenzyme A-cholesterol acyltransferase (ACAT) inhibitor, which has been clinically verified safe in other phase Ⅲ clinical trials. It can potentiate the killing function of CD8⁺ T cells by modulating cholesterol metabolism. Doxorubicin (DOX) is an anticancer drug widely used in many cancers to induce tumor cell apoptosis. Unfortunately, DOX also can induce toxic and side effects in many organs, compromising its usage and efficacy. Herein, we report the combinational usage of avasimibe and a safe pH sensitive nano-drug delivery system composing of DOX and metal–organic frameworks nanoparticles (MNPs). Our findings demonstrated that DOX–MNPs treatment inhibited tumor growth with good safety profile and avasimibe treatment combined DOX–MNPs treatment exhibited a better efficacy than monotherapies in 4T1 breast cancer therapy.     

Histone acetyltransferase p300 regulates the expression of human pituitary tumor transforming gene (hPTTG)

The human pituitary tumor transforming gene (hPTTG) serves as a marker for malignancy grading in several cancers, hPTTG is in volved in multiple cellular pathways including cell transformation, apoptosis, DNA repair, genomic instability, mitotic control and angiogenesis induction. However, the molecular mechanisms underlying hPTTG regulation have not been fully explored. In this study, we found that overexpression of histone acetyltransferase (HAT) p300 upregulated hPTTG at the levels of promoter activity, mRNA and protein expression. Moreover, the HAT activity of p300 was critical for its regulatory function. Chromatin immunoprecipitation (ChIP)analysis revealed that overexpression of p300 elevated the level of histone H3 acetylation on the hPTTG promoter. Additionally, the NF-Y sites at the hPTTG promoter exhibited a synergistic effect on upregulation of hPTTG through interacting with p300. We also found thattreatment of 293T cells with the histone deacetylase (HDAC) inhibitor Trichostatin A (TSA) increased hPTTG promoter activity. Meanwhile, we provided evidence that HDAC3 decreased hPTTG promoter activity. These data implicate an important role of the histone acetylation modification in the regulation of hPTTG.     

Digestion-Promoting Effects and Mechanisms of Dashanzha Pill Based on Raw and Charred Crataegi Fructus

Emerging evidence suggests that a high-fat diet (HFD) can influence endoplasmic reticulum (ER) stress and gut microbiota. Crataegi Fructus is a traditional Chinese herb widely used in formulas for dyspepsia, with Dashanzha Pill composed of raw Crataegi Fructus (DR) being a representative drug. Processing products of Crataegi Fructus, however, have a stronger pro-digestive effect, and we hypothesized that Dashanzha Pill composed of charred Crataegi Fructus (DC) is more effective. We found that the contents of glucose 1-phosphate and luteolin in DR and DC were substantially different via ultra-high performance liquid chromatography-hybrid quadrupole-Orbitrap high-resolution mass spectrometry. DC outperformed DR in improving histopathological changes, increasing gastrin and motilin, and decreasing vasoactive intestinal peptides in rats with HFD induced dyspepsia. Fecal microbiota analysis revealed that DC could restore the disturbed intestinal microbiota composition, including that of Bacteroides, Akkermansia, and Intestinimonas to normal levels. Furthermore, DC significantly reduced the mRNA and protein levels of glucose-regulated protein 78, protein kinase R-like ER kinase, and eukaryotic initiation factor 2α. Taken together, DC outperformed DR in relieving dyspepsia by regulating gut microbiota and alleviating ER stress.     

Cytisine attenuates bone loss of ovariectomy mouse by preventing RANKL‐induced osteoclastogenesis

Postmenopausal Osteoporosis (PMOP) is oestrogen withdrawal characterized of much production and activation by osteoclast in the elderly female. Cytisine is a quinolizidine alkaloid that comes from seeds or other plants of the Leguminosae (Fabaceae) family. Cytisine has been shown several potential pharmacological functions. However, its effects on PMOP remain unknown. This study designed to explore whether Cytisine is able to suppress RANKL‐induced osteoclastogenesis and prevent the bone loss induced by oestrogen deficiency in ovariectomized (OVX) mice. In this study, we investigated the effect of Cytisine on RAW 264.7 cells and bone marrow monocytes (BMMs) derived osteoclast culture system in vitro and observed the effect of Cytisine on ovariectomized (OVX) mice model to imitate postmenopausal osteoporosis in vivo. We found that Cytisine inhibited F‐actin ring formation and tartrate‐resistant acid phosphatase (TRAP) staining in dose‐dependent ways, as well as bone resorption by pit formation assays. For molecular mechanism, Cytisine suppressed RANK‐related trigger RANKL by phosphorylation JNK/ERK/p38‐MAPK, IκBα/p65‐NF‐κB, and PI3K/AKT axis and significantly inhibited these signalling pathways. However, the suppression of PI3K‐AKT‐NFATc1 axis was rescued by AKT activator SC79. Meanwhile, Cytisine inhibited RANKL‐induced RANK‐TRAF6 association and RANKL‐related gene and protein markers such as NFATc1, Cathepsin K, MMP‐9 and TRAP. Our study indicated that Cytisine could suppress bone loss in OVX mouse through inhibited osteoclastogenesis. All data provide the evidence that Cytisine may be a promising agent in the treatment of osteoclast‐related diseases such as osteoporosis.     

二维斑点追踪技术评价犬心梗后自体骨髓CD34＋干细胞移植对心肌功能的影响

目的应用二维斑点追踪成像超声心动图（2D-STE）,评价犬心梗后自体骨髓CD34＋干细胞移植对心肌功能的影响。方法 12只杂种犬行冠脉左前降支结扎术,导致前壁心肌梗死,随机分为两组,A组为对照组,结扎术后两周二次开胸手术,经心肌注射磷酸盐缓冲液（PBS）1 mL;B组为治疗组,结扎术后两周二次开胸手术,经心肌注射含自体骨髓CD34＋干细胞的磷酸盐缓冲液1 mL。应用STE对12只犬结扎术前、术后左室短轴基底段及心尖段心室节段径向应变（RS）、圆周方向应变（CS）以及局部心肌旋转（Rot）进行分析,并对对照组和治疗组治疗后的RS、CS及Rot变化进行比较。结果心肌梗死后梗死节段的RS、CS以及Rot均下降,治疗后治疗组梗死段RS及Rot较对照组好转。结论 STE能够评价左室短轴局部心肌的收缩功能,心肌梗死后梗死段短轴各方向应变减低,自体骨髓CD34＋干细胞移植能够提高局部心肌的收缩功能。     

Crystallization and preliminary X-ray analysis of plant class I chitinase from rice

We report here on crystallization and preliminary X-ray analysis of plant class I chitinase from rice (OsChia1b). Similar single crystals of full-length OsChia1b were obtained under two independent conditions. The crystals grown under these conditions diffracted up to 2.1 and 2.5 angstroms resolution, respectively, at a synchrotron beamline, and were found to belong to the tetragonal space group P4(3)2(1)2.