HER2, a member of epidermal growth factor receptor family proteins, is overexpressed in about 30% of human breast cancer. Increased levels of HER2 are associated with poor patient prognosis and enhanced metastasis. RNA interference (RNAi) is developed recently as a new technique which can inhibit gene expression specifically in mammalian cells. On the basis of previous study,in which two target sequences with favorable RNAi effect on HER2 were identified, a series of dual promoter siRNA-expressing vectors containing two opposing U6 and H1 promoters were constructed. After transfection of HER2-overexpressing SKBR3 breast cancer cells with the siRNA-expressing vectors, downregulation of HER2 was identified quantitatively. Subsequently, the siRNA-expressing cassettes were subcloned into lentiviral vectors by LR recombination reaction and lentivirus was prepared successfully. The results from infection of SKBR3 cells with siRNA-expressing lentivirus demonstrated that lentiviral-mediated RNAi could downregulate HER2 expression efficiently through fluorescent quantitative PCR (FQ-PCR), western blot, and FACS analysis. Furthermore, cell growth was inhibited in cell proliferation assay after treatment with siRNA lentivirus.A new tool for clarifying the function of HER2 in cancer metastasis and developing the gene therapy drug was offered.

To explore the antibacterial activity and mechanism of total alkaloids and berberine from Coptidis Rhizoma on Aeromonas hydrophila, and determine the effect of total alkaloids and berberine from Coptidis Rhizoma on minimum inhibitory concentrations, permeability and fluidity of cell membrane, conformation of membrane proteins and virulence factors of A. hydrophila. The results showed that both total alkaloids and berberine from Coptidis Rhizoma had antibacterial activities on A. hydrophila, with minimum inhibitory concentrations of 62.5 and 125 mg · L(-1), respectively. Total alkaloids and berberine from Coptidis Rhizoma could increase the fluidity of membrane, change the conformation of membrane porteins and increase the permeability of bacteria membrane by 24.52% and 19.66%, respectively. Besides, total alkaloids and berberine from Coptidis Rhizoma significantly decreased the hemolysis of exotoxin and the mRNA expressions of aerA and hlyA (P < 0.05, P < 0.01), the secretion of endotoxin and the mRNA expression of LpxC (P < 0.05, P < 0.01). The results suggested that the antibacterial activity of total alkaloids and berberine from Coptidis Rhizoma on A. hydrophila may be related to the bacteria membrane injury. They inhibited the bacterial growth by increasing membrane lipid fluidity and changing conformation of membrane proteins, and reduced the secretion of virulence factors of A. hydrophila to weaken the pathogenicity.
Aeromonas hydrophila ; drug effects ; genetics ; metabolism ; Alkaloids ; pharmacology ; Anti-Bacterial Agents ; pharmacology ; Bacterial Proteins ; genetics ; metabolism ; Bacterial Toxins ; biosynthesis ; Berberine ; pharmacology ; Cell Membrane ; drug effects ; genetics ; metabolism ; Coptis ; chemistry ; Drugs, Chinese Herbal ; pharmacology ; Membrane Fluidity ; drug effects ; Rhizome ; chemistry

To investigate the practicability of establishing zebrafish lipid-lowering drug screening model and the effect of berberine (BBR) on hyperlipidemic zebrafish. Three-month-old zebrafishes were fed with 4% cholesterol for 0, 2, 4, 8, 14, 20, 25, 30 days, and the level of total cholesterol in serum was measured. Zebrafish were randomly divided into four groups: the control group, the high cholesterol diet group, the 0.01% simvastatin-treated group, the 0.1% berberine-treated group and the 0.2% berberine-treated group. The levels of total cholesterol (TC), triglyceride (TC), low density lipoprotein cholesterol (LDL-c) and high-density lipoprotein cholesterol (HDL-c) in serum were measured; the expression of hepatic HMGCR, LDLR and CYP7A1a mRNA expressions were detected by real time PCR. Oil red O staining was performed to observe the changes in fat content in the liver. According to the result, the level of serum TC in the 4% cholesterol diet group significantly was higher than that of the normal control group in a time-dependent manner and reached a stable level at the 20th day. The BBR group showed significant decreases in the levels of TC, TG and LDL-c, HMGCR mRNA expression and fat content and increases in LDLR and CYP7A1a mRNA. The hyperlipidemia zebrafish model was successfully established by feeding with 4% cholesterol for 20 days. The findings lay a foundation for further screenings on lipid-lowering drugs.
Animals ; Berberine ; administration & dosage ; Cholesterol ; metabolism ; Disease Models, Animal ; Drugs, Chinese Herbal ; administration & dosage ; Female ; Humans ; Hyperlipidemias ; drug therapy ; metabolism ; Hypolipidemic Agents ; administration & dosage ; Liver ; drug effects ; metabolism ; Male ; Triglycerides ; metabolism ; Zebrafish ; metabolism

An anti-alpha-synuclein (alpha-SYN) monoclonal antibody produced in our laboratory was used to investigate the effect of repeated acute hypoxic treatments on the expression of alpha-SYN in the mouse cerebral cortex. Western blot analysis showed that the expression levels of alpha-SYN in the cortex changed accordingly upon hypoxic exposure times, as that the alpha-synuclein level significantly increased after the first hypoxic exposure and then dropped down to the background level after the fourth hypoxic exposure. Immunohistochemical staining revealed that the alpha-SYN-immunopositive substance was localized not only in the nerve endings, but also within the nuclei of some neurons. The cell density of the neurons with alpha-SYN immunopositive nuclei was increased significantly after the first hypoxic exposure but returned back to control levels after the fourth hypoxic exposure. Our results indicate that both of the alpha-SYN expression level in the brain and the number of the neurons with alpha-SYN positive nuclei are affected by the repeated acute hypoxic treatments and that this modification is hypoxic time-dependent. The mechanism and the physiological significance underlying these changes need to be further investigated.
Animals ; Brain ; blood supply ; Brain Ischemia ; metabolism ; Cerebral Cortex ; metabolism ; Ischemic Preconditioning ; Mice ; Mice, Inbred BALB C ; Nerve Tissue Proteins ; biosynthesis ; genetics ; Neurons ; metabolism ; Phosphoproteins ; biosynthesis ; genetics ; Random Allocation ; Synucleins ; alpha-Synuclein

BACKGROUNDTo confirm if Puumala like viruses exist in China.

METHODSRNA was extracted from lungs of bank voles captured in the Northeast China, partial S segments genome of Puumala viruses were amplified and sequenced.

RESULTS926 bp cDNA of S segments of Puumala like virus was amplified and sequenced. The phylogenetic analysis revealed that the Puumala like viruses found in China were most close to that found in Far East region of Russia.

CONCLUSIONSPuumala like virus does exist in Northeast China, and the nucleotides sequence of the viruses have high homolog to Puumala viruses found in Russia.

Animals ; China ; DNA, Viral ; analysis ; Hemorrhagic Fever with Renal Syndrome ; virology ; Lung ; virology ; Mice ; Phylogeny ; Puumala virus ; isolation & purification ; Sequence Analysis, DNA ; Sequence Homology, Nucleic Acid