Abstract: At present, nucleic acid detection technology based on the PCR principle is commonly used to detect malaria parasites, the existing Plasmodium detection methods mainly include microscopy, antigen immunoassay, and nucleic acid detection,but due to the long detection time, high personnel and equipment requirements, and other shortcomings, its popularization, and application at the grassroots level are limited. What challenges previous Plasmodium detection methods are the lack of experienced professionals and advanced equipment at the grassroots as well as the requirement of rapid detection of large samples under extreme conditions. The isothermal amplification technology developed in recent years has potential application prospects due to its simplicity, rapidity, high sensitivity, and high specificity. This article attempts to review the principles, characteristics, and prospects of various isothermal amplification technologies, and on this basis, focuses on the introduction of recombinase polymerase amplification (RPA) and recombinase⁃aided isothermal amplification (RAA) assay technologies and proposes the use of such recombinant enzyme amplification technologies to achieve rapid and accurate diagnosis of common Plasmodium species possibility and imagination.

An acute myeloid leukemic HB-1 cell line was cloned and established from the spleen cells of irradiated CBA/N mice. Acute myeloma leukemia-like syndrome would be induced in normal CBA/N mice after intravenous injection of HB-1 cells, and the death of mouse happened within about two weeks. In general, leukemic cells transplanted into the mice would infiltrate into the hematopoietic organs, lungs, kidneys and liver. An interesting observation in our study was that HB-1 cells were present not only in the lung, kidney, and liver but also in the cerebrum and cerebellum. It was beyond our expectation that the leukemic cells could go through the blood-brain barrier in most circumstances. On the basis of the observation, we expect that HB-1 cells could be used as a very useful model to elucidate the mechanism of infiltrating the blood-brain barrier for certain type of cells.
Animals ; Blood-Brain Barrier ; physiopathology ; Brain ; pathology ; Cell Line, Tumor ; Central Nervous System Neoplasms ; Leukemia, Experimental ; pathology ; Leukemia, Myeloid, Acute ; pathology ; Mice ; Mice, Inbred CBA ; Neoplasm Invasiveness ; Neoplasm Transplantation

The aim of the research is to investigate the genetic characteristics of Legionella pneumophila serogroup1 (LP1)in Sichuan Province.The sequence-based typing (SBT) and multiple-locus VNTR analysis (MLVA) were used to describe the genetic polymorphism of 42 strains which were isolated from 1989-2016 in Sichuan Province,China.According to the reference,PCR was used to detect the 8-VNTR loci and 7 housekeeping genes respectively.The VNTR results were determined by using capillary electrophoresis,and the SBT results were sequenced and compared with the database of EWGLI.Results showed that totally 42 stains were divided into 8 MLVA types with the advantage types were M08 (47.6 ％) and M07 (23.8 ％).Twelve ST types were obtained with 3 main clonal complex and 2 singleton,including 2 novel ST types,among those,ST1 was the predominant type,accounting for 52.3 ％,following by ST630 (14.2 ％).In conclusion,our results demonstrated MLVA and SBT were both applied to the research for molecular epidemiological investigation of LP1 and showed the high genetic polymorphism and the regional specificity.The results also suggest that the isolates are a potential threat to the public,effective control and prevention strategies are urgently needed.

To investigate the improving effect of inter-chain disulfide formation on protein trans-splicing, we introduce a Cys point mutation at Tyr(664) in heavy chain and at Thr(1826) in light chain of B-domain-deleted FVIII (BDD-FVIII). By co-transfection of COS-7 cell with the two Cys mutated chain genes, the intracellular protein splicing, inter-chain disulfide formation, secreted BDD-FVIII and bioactivity in culture supernatant were observed. The data showed that a strengthened spliced BDD-FVIII with an inter-chain disulfide detected by Western blotting and an elevated secretion of spliced BDD-FVIII (128 +/- 24 ng mL(-1)) compared to control (89 +/- 15 ng mL(-1)), assayed by a sandwich ELISA. A Coatest was performed to assay the secretion of bioactivity in culture supernatant and shown a much higher value (0.94 +/- 0.08 u mL(-1)) compared to that of control (0.62 +/- 0.15 u mL(-1)). It suggests that inter-chain disulfide formation could improve protein trans-splicing based dual-vector delivery of BDD-FVIII gene providing experimental evidence for ongoing in vivo study.
Animals ; COS Cells ; Cercopithecus aethiops ; Cysteine ; genetics ; metabolism ; Disulfides ; metabolism ; Factor VIII ; genetics ; metabolism ; Gene Transfer Techniques ; Genetic Vectors ; Mutation ; Peptide Fragments ; genetics ; metabolism ; Protein Splicing ; Transfection

OBJECTIVETo investigate the antiinflammatory activities of aqueous extract of Occimum gratissmium (OGE) with emphasis on expression of proinflammatory cytokines in Lipopolysaccharide (LPS)-stimulated epithelial cell BEAS-2B.

METHODSEffects of OGE on cell viability were determined by MTT assay. mRNA expression were analyzed by and reverse transcription polymerase chain reaction (RT-PCR) and quantitative real-time PCR. Activation of kinase cascades was investigated by immunoblot. Intracellular reactive oxygen species (ROS) was analyzed by flow cytometry.

RESULTSOGE (<200 μg/mL) treatment or pretreatment and following LPS exposure slightly affected viability of BEAS-2B cells. Increase of interleukin (IL)-6 and IL-8 and the elevated level of intracellular ROS in LPS-stimulated BEAS-2B cells were diminished by OGE pretreatment in a dose-dependent manner. OGE suppressed inflammatory response-associated mitogen-activated protein kinases (MAPKs) and Akt activation. Additionally, OGE pretreatment increased level of cellular inhibitor of κBα (IκBα) and inhibited nuclear translocation of nuclear factor kappa B (NF-κB).

CONCLUSIONThese findings indicate that significant suppression of IL-6 and IL-8 expressions in LPS-stimulated BEAS-2B cells by OGE may be attributed to inhibiting activation of MAPKs and Akt and consequently suppressing nuclear translocation of NF-κB.

Cell Nucleus ; drug effects ; metabolism ; Cell Survival ; drug effects ; Cytosol ; drug effects ; metabolism ; Epithelial Cells ; drug effects ; enzymology ; metabolism ; Gene Expression Regulation ; drug effects ; Humans ; I-kappa B Proteins ; metabolism ; Interleukin-6 ; genetics ; metabolism ; Interleukin-8 ; genetics ; metabolism ; Intracellular Space ; drug effects ; metabolism ; Lipopolysaccharides ; pharmacology ; Mitogen-Activated Protein Kinases ; metabolism ; NF-KappaB Inhibitor alpha ; NF-kappa B ; metabolism ; Ocimum ; chemistry ; Phosphorylation ; drug effects ; Plant Extracts ; pharmacology ; Protein Transport ; drug effects ; Proto-Oncogene Proteins c-akt ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Reactive Oxygen Species ; metabolism ; Respiratory System ; cytology ; Water

The mutation of cystic fibrosis transmembrane conductance regulator (CFTR) gene leads to an autosomal recessive genetic disorder cystic fibrosis (CF). The gene therapy for CF using adeno-associated virus (AAV) vectors delivering CFTR gene is restricted by the contents limitation of AAV vectors. In this study the split CFTR genes severed at its regulatory domain were delivered by a dual-vector system with an intein-mediated protein trans-splicing as a technique to investigate the post-translational ligation of CFTR half proteins and its function as a chloride ion channel. A pair of eukaryotic expression vectors was constructed by breaking the human CFTR cDNA before Ser712 codon and fusing with Ssp DnaB intein coding sequences. After co-transfection into baby hamster kidney (BHK) cells followed by transient expression, patch clamps were carried out to record the chloride current of whole-cell and the activity of a single channel, and the ligation of two halves of CFTR was observed by Western blotting. The results showed that the intein-fused half genes co-transfected cells displayed a high whole cell chloride current and activity of a single channel indicating the functional recovery of chloride channel, and an intact CFTR protein band was figured out by CFTR-specific antibodies indicating that intein can efficiently ligate the separately expressed half CFTR proteins. The data demonstrated that protein splicing strategy could be used as a strategy in delivering CFTR gene by two vectors, encouraging our ongoing research program on dual AAV vector system based gene transfer in gene therapy for cystic fibrosis.
Animals ; Cells, Cultured ; Chlorides ; metabolism ; Codon ; genetics ; Cricetinae ; Cystic Fibrosis ; therapy ; Cystic Fibrosis Transmembrane Conductance Regulator ; genetics ; metabolism ; DNA, Complementary ; genetics ; Dependovirus ; genetics ; Genetic Therapy ; Genetic Vectors ; Humans ; Inteins ; physiology ; Kidney ; cytology ; Protein Processing, Post-Translational ; Recombinant Proteins ; genetics ; metabolism ; Trans-Splicing ; Transfection

Based on the deletion information of high virulent PRRSV genome, 3 oligonucleotide primer were designed and synthesized. Specific and sensitive reverse transcription-PCR (RT-PCR) assays were de-veloped for the detection of high virulent PRRSV. The sensitivity and specificity of RT-PCR assays were evaluated, the results showing that the detection limit of the assay was found to be 0.265 pg of tissue total RNA, and the protocol have no cross-reaction with classical swine fever virus, porcine circovirus type 2,pseudorabies virus, streptococcus, haemophilus parasuis and Escherichia coli. Then 36 cell cultures, two PRRSV live vaccine strains and 184 clinical specimens from 52 farms were tested. Five PRRSV field iso-lates were the high virulent PRRSV; two PRRSV live vaccine strains from normal PRRSV, and 123 speci-mens from 42 farmer were positive (only 1 specimen was normal PRRSV). This RT-PCR method proved to be accurate differential diagnosis of the high virulent PRRSV and normal PRRSV with the characteristics of rapidity, sensitivity and specificity, and has a strong clinical relevance.

In our recent study by exploring an intein-based dual-vector to deliver a B-domain-deleted FVIII (BDD-FVIII) gene, it showed that covalently ligated intact BDD-FVIII molecules with a specific coagulant activity could be produced from expressed heavy and light chains by protein trans-splicing. Here, we assessed the hypothesis that the efficiency of trans-splicing may be increased by adding to the intein sequences a pair of leucine zippers that are known to bring about specific and strong protein binding. The intein-fused heavy and light chain genes were co-transferred into cultured COS-7 cells using a dual-vector system. After transient expression, the intracellular BDD-FVIII splicing was observed and the spliced BDD-FVIII and bioactivity secreted to culture media were quantitatively analyzed. An enhanced splicing of BDD-FVIII with decreased protein precursors from gene co-transfected cells was observed by Western blotting. The amount of spliced BDD-FVIII and bioactivity secreted to the culture media were 106 +/- 12 ng x mL(-1) and 0.89 +/- 0.11 U x mL(-1) analyzed by ELISA and Coatest method respectively, which was greater than leucine zipper free intein-fused heavy and light chain genes co-transfected cells (72 +/- 10 ng x mL(-1) and 0.62 +/- 0.07 U x mL(-1)). The activity of cellular mechanism-independent protein splicing was also improved, as showed by the increasing of spliced BDD-FVIII and bioactivity in culture media from combined cells separately transfected with heavy and light chain genes which was 36 +/- 11 ng x mL(-1) and 0.28 +/- 0.09 U x mL(-1). It demonstrated that the leucine zippers could be used to increase the efficiency of protein trans-splicing to improve the efficacy of a dual-vector mediated BDD-FVIII gene delivery by strengthening the interaction between the two intein-pieces fused to heavy and light chains. It provided evidence for further study in animal model using a dual-adeno-associated virus vector to deliver FVIII gene in vivo.
Animals ; COS Cells ; Cercopithecus aethiops ; Factor VIII ; chemistry ; genetics ; metabolism ; Genetic Vectors ; Inteins ; Leucine Zippers ; Peptide Fragments ; chemistry ; genetics ; metabolism ; Protein Splicing ; Trans-Splicing ; Transfection

Although two chain transfering separately could be used to overcome the volume limitation of adeno-associated virus vectors (AAV) in coagulation factor VIII (FVIII) gene delivery, it leads to chain imbalance for inefficient heavy chain secretion. In this study we aimed to improve the efficacy of two chain strategy in FVIII gene delivery through the degradation of glucose-regulated protein 78 (GRP78) known as a protein chaperone in endoplasmic reticulum (ER) by deoxynivalenol (DON) to decrease GRP78-bound FVIII heavy chain. By treating the two-chain gene transduced 293 cells with DON, the heavy chain (HC) secretion and FVIII bioactivity were observed. Data showed that 293 cells after three hours post-treatment with DON at a concentration of 500 ng mL(-1) resulted in obvious decrease the level of GRP78 but no effect on the cell proliferation. The HC secreted from DON-treated cells transfected with HC gene alone was 59 +/- 11 ng mL(-1), higher than that secreted by control cells (15 +/- 4 ng mL(-1)), and the HC secretion was further increasing to 146 +/- 34 ng mL(-1) in light chain (LC) gene co-transfected cells with an activity measured up to 0.66 +/- 0.15 U mL(-1), also greater than control cells (76 +/- 17 ng mL(-1) and 0.35 +/- 0.09 U mL(-1)). Taken together, these data suggest that DON-mediated GRP78 down-regulation could improve the efficacy of two-chain FVIII gene transfering by facilitating HC secretion, providing an experimental basis for in vivo dual-AAV application in FVIII gene delivery.
Cell Proliferation ; Down-Regulation ; Factor VIII ; chemistry ; genetics ; secretion ; Gene Transfer Techniques ; HEK293 Cells ; Heat-Shock Proteins ; metabolism ; Humans ; Transfection ; Trichothecenes ; pharmacology

Using the weight-average molecular weight 50 000 polylactic acid (PLA) as a carrier, and a certain proportion of erythromycin (EM) and prednisone acetate (PNA) to mixed prepare the compound erythromycin sustained release preparation (sustained-release tablets). Using ultraviolet spectrophotometry and high performance liquid chromatography (HPLC) to detect separately the release amount of EM and PNA in vitro medium. The sustained-release tablets release for about 21 days, the average content of EM is 99.7 mg/table, RSD = 0.82%; and the average content of PNA is 10.03 mg/table, RSD = 0.93%. Within 21 days, the cumulative releases of EM and PNA are 86.1% and 78.3%, respectively. The drug release is steady and slow after 5 days, the burst release phenomenon in early stage is more significant. The results showed that the sustained-release tablet preparation method is feasible, the release performance is good and the clinical efficacy is significant.
Chromatography, High Pressure Liquid ; Delayed-Action Preparations ; administration & dosage ; chemistry ; therapeutic use ; Drug Carriers ; Drug Combinations ; Erythromycin ; administration & dosage ; chemistry ; therapeutic use ; Humans ; Lactic Acid ; administration & dosage ; Polyesters ; Polymers ; administration & dosage ; Prednisone ; administration & dosage ; chemistry ; therapeutic use ; Sinusitis ; drug therapy ; Spectrophotometry, Ultraviolet ; Tablets