Polyinosinic-polycytidylic acid is a synthetic analog of double-stranded RNA,which plays a vital role in the regulation of immune system.Toll-like receptor 3 ( TLR3 ),melanoma differentiation-associated gene 5 (MAD-5) and retinoic acid inducible gene - Ⅰ ( RIG- Ⅰ ) are the main three intracellular receptors binding to polyinosinic-polycytidylic acid which activates human anti-tumor immune responses including the activation of innate immunity and acquired immunity through TIR-domain-containing adapter-inducing inter feron-β (TRIF) and interferon-β.Thus,polyinosinic-polycytidylic acid plays an important role in regulating anti-tumor immune responses.The immunoregulation mechanisms ofpolyinosinic-polycytidylic acid in melanoma,breast cancer,malignant glioma and lung cancer have been clarified,which will provide new strategies for tumor immunotherapy.

Objective:Effects of oxymatrine on the sodium current were studied .Methods:The whole cell voltage clamp technique was used in isolated ventricular cells of guinea-pig.Results:Oxymatrine (0.1,0.3 and 1 mmol/L) showed inhibition to the sodium current in dose-dependence.Conclusion:These results indicate that inhibition of oxymatrine to the sodium current may be one of mechanisms of its antiarrhythmic action.

AIM: To investigate the key molecular mechanism of inflammatory response in alveolar epithelial cells induced by nontypeable haemophilus influenzae(NTHi).METHODS: A549 cells were co-cultured with NTHi(multiplicity of infection,MOI: 10) and harvested 15 min and 30 min after stimulation.The phosphorylation of p38 mitogen activated protein kinase(p38 MAPK) in A549 cells was detected by Western blotting.The intracellular expression of nuclear factor-?B(NF-?B) p65 was examined by flow cytometry 4 h after stimulation.A549 cells were preincubated with p38 inhibitor(SB203580) or NF-?B inhibitor(PDTC) for 1 h and then stimulated with NTHi for 24 h.The level of interleukin 8(IL-8) in the supernatants was determined by enzyme-linked immunosorbent assay(ELISA).RESULTS: The phosphorylation of p38 MAPK was rapidly induced by NTHi stimulation.The expression of NF-?B p65 in A549 cells after NTHi stimulation was significantly up-regulated compared with control group(P

Objective To investigate the effect and mechanism of sphingosine 1-phosphate(S1P)on action potential(AP)and voltage-dependent potassium current(KV)in isolated guinea pig ventricular myocytes.Methods The ventricular myocytes were isolated by using Langendorff perfusion method.The AP and KV were recorded by whole cell patch-clamp recording technique.Results S1P prolonged the 50% and 90% action potential duration(APD50 and APD90)and decreased KV which were blocked by pertussis toxin(PTX)or Calphostin C.Conclusion S1P decreased KV in a PKC pathway and prolonged action potential duration in guinea-pig ventricular myocytes.

Spiramycin and midecamycin are 16-membered macrolide antibiotics with very similar chemical structures. Spiramycin has three components, namely spiramycin I, II and III. Spiramycin II and III are, respectively, the O-acetyl and propionyl derivatives at C3-hydroxyl group of spiramycin I. Midecamycin has four components, and the C3-hydroxyl group of midecamycin is all O-propionylated. The enzyme adding acyl group(s) at the C3-hydroxyl group during the biosynthesis of spiramycin and midecamycin is 3-O-acyltransferase. The 3-O-acyltransferases for spiramycin and midecamycin are also very similar, and presume to function when exchanged. To explore whether the 3-O-acyltransferase for midecamycin biosynthesis hold still the character of selective and efficient propionylation for spiramycin I at its C3-hydroxyl group, we inserted mdmB, the 3-O-acyltransferase gene from Streptomyces mycarofaciens ATCC 21454 for midecamycin biosynthesis, into a mutant strain of S. spiramyceticus F21, in which the 3-O-acyltransferase gene for spiramycin biosynthesis, sspA, was deleted; and the mdmB was integrated exactly into the chromosomal site where the sspA was deleted. We name this "hybrid" strain as SP-mdmB. HPLC analysis of the spiramycin produced by SP-mdmB showed that spiramycin I was still the major component, although the relative proportions of both spiramycin II and III increased significantly. We thus conclude that MdmB from Streptomyces mycarofaciens ATCC 21454 for midecamyicn biosynthesis do not hold the character of selective and efficient propionylation for spiramycin I within S. spiramyceticus F21, and this character is possibly limited in Streptomyces mycarofaciens ATCC 21454 for midecamycin biosynthesis.
Acylation ; Acyltransferases ; genetics ; metabolism ; Culture Media ; Genes, Bacterial ; Genetic Engineering ; methods ; Leucomycins ; biosynthesis ; Spiramycin ; biosynthesis ; Streptomyces ; enzymology ; genetics ; Substrate Specificity

BACKGROUNDVitamin D supplementation is believed to be beneficial in the treatment of patients with tuberculosis (TB), however, results from clinical trials have been inconclusive.

METHODSWe performed a systematic literature search across MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, Springer, EBSCO, ProQuest, HighWire Press, and Web of Science, published as of December 2013. We individually inspected citations and extracted data independently. We estimated pooled risk ratios (RR) and 95% confidence intervals (CI) using random-effect models. We also assessed risk of bias using the Jadad scale and the quality of the evidence using GRADE. We included all randomized controlled trials comparing vitamin D with or without standard TB therapy or placebo.

RESULTSA total of five studies were analyzed in our meta analysis covering 841 newly-diagnosed TB cases. Patients receiving vitamin D supplementation had a 39% reduced risk of sputum smear or culture positive after six weeks of anti-TB treatment than those in the control group, although this is not statistically significant (pooled RR 0.61, 95% CI 0.24 to 1.56, P = 0.30). Apart from an increased serum vitamin D level in the supplement group after eight weeks of treatment there was no evidence of any additional adverse effects related to vitamin D.

CONCLUSIONSThe meta analysis results indicate that vitamin D supplementation does not seem to have any beneficial effect in the treatment of TB. Future rigorous randomized controlled trials are needed to explore whether the supplementation of vitamin D could shorten treatment duration and to confirm whether the polymorphisms of vitamin D receptor have any potentially beneficial effect.

Dietary Supplements ; Humans ; Randomized Controlled Trials as Topic ; Tuberculosis ; blood ; drug therapy ; Vitamin D ; blood ; therapeutic use

Cell-free transcription and translation (TXTL) system is a cell extract-based system for rapid in vitro protein expression. The system bypasses routine laboratory processes such as bacterial transformation, clonal screening and cell lysis, which allows more precise and convenient control of reaction substrates, reduces the impact of bacteria on protein production, and provides a high degree of versatility and flexibility. In recent years, TXTL has been widely used as an emerging platform in clusterd regularly interspaced short palindromic repeat (CRISPR) technologies, enabling more rapid and convenient characterization of CRISPR/Cas systems, including screening highly specific gRNAs as well as anti-CRISPR proteins. Furthermore, TXTL-based CRISPR biosensors combined with biological materials and gene circuits are able to detect pathogens through validation of related antibiotics and nucleic acid-based markers, respectively. The reagents can be freeze-dried to improve portability and achieve point-of-care testing with high sensitivity. In addition, combinations of the sensor with programmable circuit elements and other technologies provide a non-biological alternative to whole-cell biosensors, which can improve biosafety and accelerate its application for approval. Here, this review discusses the TXTL-based characterization of CRISPR and their applications in biosensors, to facilitate the development of TXTL-based CRISPR/Cas systems in biosensors.
CRISPR-Cas Systems ; Bacteria

ObjectiveTo investigate the clinical effect and safety of robot-assisted laparoscopic hepatectomy (RALH) versus open hepatectomy (OH) in the treatment of liver diseases. MethodsWeb of Science, PubMed, Cochrane Library, Embase, CNKI, CBM, VIP, and Wanfang Data were searched for Chinese and English articles on RALH versus OH in the treatment of liver diseases published up to February 2020. The quality of the articles included was assessed, and RevMan 5.1 was used to perform the meta-analysis. ResultsSeven studies were included, with a total of 754 patients (328 patients in the RALH group and 426 in the OH group). The meta-analysis showed that compared with the OH group, the RALH group had a significantly longer time of operation (mean difference ［MD］=59.41, 95% confidence interval ［CI］: 9.74-109.08, P=0.02), significantly higher blood transfusion rate (relative risk ［RR］=2.24, 95%CI: 1.04-4.82, P=0.04) and rate of hepatic portal occlusion (RR=2.27, 95%CI: 1.37-3.75, P=0.001), a significantly shorter length of hospital stay (MD=-3.87, 95%CI: -5.63 to -2.12,P＜0.001), and significantly lower overall incidence rate of postoperative complications (RR=0.58, 95%CI: 0.41-0.81, P=0.001) and incidence rates of major postoperative complications (RR=0.45, 95%CI: 0.22-0.91, P=0.03). There was no significant difference in intraoperative blood loss between the two groups (P＞0.05). ConclusionFor hepatectomy, RALF can shorten the length of hospital stay and reduce postoperative complications, creating conditions for minimally invasive hepatectomy and rapid recovery.