[Effect of BCYRN1 on proliferation and migration of airway smooth muscle cells in rat model of asthma].

Objective: To detect the effect of brain cytoplasmic RNA 1 (BCYRN1) on the proliferation and migration of airway smooth muscle cells (ASMCs) in rat model of asthma. Methods: Male SD rats were randomly divided into control group and asthma group (n=10 each). The ovalbumin (OVA) model was constructed in asthma group. Real time-qPCR was performed to detect the level of BCYRN1 in the ASMCs separated from the airway tissue of these rats. Then 2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2, 4-disulfophenyl)-2H-tetrazolium (WST-1) assay, roche real-time cell analyzer assay and Transwell cell migration assay were performed to detect the viability/proliferation and migration of ASMCs which were transfected with Ad-BCYRN1.Platelet-derived growth factor (PDGF)-BB was used to treat ASMCs to induce proliferation and migration, and the level of BCYRN1 was examined.The viability/proliferation and migration of ASMCs treated with PDGF-BB and transfected with si-BCYRN1 were detected. Inspiratory resistance and expiratory resistance were measured in rats with BCYRN1 knockdown.Briefly, rats were randomly divided into four groups: control (group A), sensitization + Ad-GFP (group B), sensitization + AdSM22α-siBCYRN1 (group C), control + Ad-SM22α-siBCYRN1 (group D) (n=10 each). The corresponding adenovirus vectors were sent to lung of group B, group C and group D through nasal spray. The OVA model was constructed in group B and group C. The rats in group A and group D were treated with saline.After 24 h of the last treatment with OVA or saline, rats of each group were given tracheal intubation, connected with breathing machine. Rats were injected with methacholine to measure the inspiratory resistance and expiratory resistance. Results: The level of BCYRN1 in ASMCs separated from rats in asthma group and in ASMCs treated with PDGF-BB was 3.60±0.45 and 3.53±0.35, respectively, significantly higher than those of the corresponding control (both P<0.01). Ad-BCYRN1 significantly increased the expression of BCYRN1 in ASMCs. The cell viability and proliferation rates of ASMCs transfected with Ad-BCYRN1 increased 1.75-and 1.47-fold compared to those of the control group, respectively (P<0.01); mobility increased 2.42-fold compared to that of the control group (all P<0.01). BCYRN1 knockdown reversed the increasing proliferation and migration of ASMCs induced by PDGF-BB. The cell proliferation rate and cell migration number in the PDGF-BB treatment group were (4.87±0.21)% and 80.00±5.00, respectively, which were significant higher than those in the si-BCYRN1 transfected group ((3.63±0.21)% and 25.33±2.52, all P<0.01). BCYRN1 knockdown reduced the inspiratory resistance and expiratory resistance in sensitization + Ad-SM22α-siBCYRN1 group. When the concentration of acetylcholine reached 1 mg/kg, the inspiratory resistance in the group A, group B, group C, and group D were 8.27±0.21, 25.40±0.56, 12.07±0.67 and 8.40±0.46 cmH2O·s·ml-1, and expiratory resistance were 13.30±0.56, 38.37±1.33, 16.40±0.56 and 13.40±0.46 cmH2O·s·ml-1, respectively (all P<0.01). Conclusion: Overexpression of BCYRN1 promotes the proliferation and migration of ASMCs in rat model of asthma.

Genome-wide identification and expression profiling of the fatty acid desaturase gene family in the silkworm, Bombyx mori.

Fatty acid desaturases exist in all living organisms and play important roles in many different biologic processes, such as fatty acid metabolism, lipid biosynthetic processes, and pheromone biosynthetic processes. Using the available silkworm genome sequence, we identified 14 candidate fatty acid desaturase genes. Eleven genes contain 3 conserved histidine cluster motifs and 4 transmembrane domains, but their N-terminal residues exhibit obvious diversity. Phylogenetic analysis revealed that there are 6 groups; Bmdesat1 and Bmdesat5-8 were clustered into group 2, which is involved in Δ11 desaturation activity, and Bmdesat3-4 were grouped in group 1, which is involved in Δ9 desaturation activity. Twelve of the 14 genes have expressed sequence tag evidence. Microarray data and reverse transcription polymerase chain reaction analysis demonstrated that Bmdesat3-4 and Bmdesat10 were expressed from the larval to moth stages and in multiple tissues on day 3 of 5th instar larvae. Bmdesat9, Bmdesat11, and Bmdesat14 were expressed during the pupal and late-embryonic stage, suggesting that they may take part in fatty acid metabolism to provide energy. These results provide some insights into the functions of individual fatty acid desaturases in silkworm.

Calcium carbonate nanoparticle delivering vascular endothelial growth factor-C siRNA effectively inhibits lymphangiogenesis and growth of gastric cancer in vivo.

A nonviral gene carrier, calcium carbonate (CaCO3) nanoparticle, was evaluated for efficient in vitro and in vivo delivery of small interfering RNA (siRNA) targeting vascular endothelial growth factor-C (VEGF-C). The chemically synthesized CaCO3 nanoparticle has a 58 nm diameter and +28.6 mV positive surface charge. It is capable of forming a CaCO3 nanoparticle-DNA complex and transferring DNA into targeted cells with high transfection efficiency while effectively protecting the encapsulated DNA from degradation. Furthermore, the CaCO3 nanoparticle-DNA complex has no obvious cytotoxicity for SGC-7901 cells, while a liposome-DNA complex exhibited measurable cytotoxicity. SGC-7901 cells transfected with a VEGF-C-targeted siRNA via CaCO3 nanoparticle exhibit significantly reduced VEGF-C expression as measured by real-time PCR and enzyme-linked immunosorbent assay; whereas no decrease in VEGF-C expression is observed in cells treated by control transfection. Transfection of SGC-7901 cells with VEGF-C siRNA via CaCO3 nanoparticle also dramatically suppresses tumor lymphangiogenesis, tumor growth and regional lymph-node metastasis in subcutaneous xenografts. Significant downregulation of VEGF-C messenger RNA expression in a subcutaneous xenograft derived from VEGF-C siRNA-treated SGC-7901 cells was confirmed by real-time PCR as compared to controls. We conclude that CaCO3 nanoparticle is a novel and nonviral system for effective delivery of siRNA for cancer gene therapy.

Histological observations on transovarial transmission of a yeast-like symbiote in Nilaparvata lugens Stal (Homoptera, Delphacidae).

Transovarial transmission of a yeast-like symbiote (YLS) in the brown planthopper, Nilaparvata lugens Stal, was observed with light and electron microscopy. Light micrographs showed that there was no YLS in testes and spermathecae of the mated females, indicating that sperm is not involved in the transovarial transmission of the symbiote. Both light and electron micrographs showed the processes of YLS transmission from fat body to the oocyte. In females, the symbiotes in mycetocytes moved out of the syncytium, which is formed from a layer of fat body cells, by exocytosis, and released into hemocoel. Then, the free YLS in hemolymph approached to the ovarioles near pedicel and were enclosed by follicle cells. They entered the follicle cells around the primary oocyte by endocytosis at epithelial plug of the ovariole. The YLS aggregated at the posterior end of the mature egg after entering, and finally formed a symbiote ball.

A new method for seed oil body purification and examination of oil body integrity following germination.

Plant seeds store triacylglycerols as energy sources for germination and postgerminative growth of seedlings. The triacylglycerols are preserved in small, discrete, intracellular organelles called oil bodies. A new method was developed to purify seed oil bodies. The method included extraction, flotation by centrifugation, detergent washing, ionic elution, treatment with a chaotropic agent, and integrity testing by use of hexane. These processes subsequently removed non-specifically associated or trapped proteins within the oil bodies. Oil bodies purified by this method maintained their integrity and displayed electrostatic repulsion and steric hindrance on their surface. Compared with the previous procedure, this method allowed higher purification of oil bodies, as demonstrated by SDS-PAGE using five species of oilseeds. Oil bodies purified from sesame were further analyzed by two-dimensional gel electrophoresis and revealed two potential oleosin isoforms. The integrity of oil bodies in germinating sesame seedlings was examined by hexane extraction. Our results indicated that consumption of triacylglycerols reduced gradually the total amount of oil bodies in seedlings, whereas no alteration was observed in the integrity of remaining oil bodies. This observation implies that oil bodies in germinating seeds are not degraded simultaneously. It is suggested that glyoxisomes, with the assistance of mitochondria, fuse and digest oil bodies one at a time, while the remaining oil bodies are preserved intact during the whole period of germination.

Brain alveococcosis. Therapeutic experience in 14 cases.

Brain alveococcosis is a rare but threatening disease. In most cases, it metastasized to the brain with late liver or lung alveococcosis. In 14 cases, 8 were secondary, and 6 primary. Nine were treated operatively, 2 medically and 3 proved by autopsy. Eleven cases were monomassive, 2 were multifocal and 1 was extra-cerebral in the cranial base. According to our experiences, extirpation is a radical method, and can improve the cerebral function confirmed by BEAM. Long-period use of albendazole showed calcified lesions of CT and disappearance of clinical symptoms.

Loss of three major auto phosphorylation sites in the EGF receptor does not block the mitogenic action of EGF.

The EGF receptor cDNA has been transfected into receptor-negative Chinese hamster ovary (CHO) cells. A mutant cell line (CHO 11) was isolated that expresses a receptor of lower molecular weight than the EGF receptor from A431 cells (150,000 daltons compared to 170,000 daltons) and which appeared as a doublet on SDS-PAGE. By digestion of the receptor with endoglycosidase F it was shown that an altered pattern of glycosylation could not account for the smaller size of the protein, although it could explain the appearance of the CHO 11 receptor as a doublet protein. A deletion was located to the transfected cDNA and shown to involve the removal of coding sequences for the most C-terminal 20,000 daltons of the EGF receptor, which contains the three major autophosphorylation sites. Despite the loss of these sites the EGF receptor from CHO 11 cells binds EGF, demonstrates protein tyrosine kinase activity in response to EGF, and transduces a mitogenic signal. The CHO 11 receptor protein is still autophosphorylated on alternative tyrosine residues. We conclude that phosphorylation of the three tyrosines (P1, P2, and P3) in the C-terminal domain of the receptor is not required for signal transduction by the EGF receptor in these cells.

Platelet-derived growth factors as possible mediators of vascular proliferation in the sporadic haemolytic uraemic syndrome.

Mitogenic activity was measured in matched plasma and serum samples from 17 children with typical epidemic haemolytic uraemic syndrome (HUS), 13 with atypical sporadic HUS, 7 with other renal diseases, and 8 normal children. The serum mitogenic activity of the normal children (median 18.35, range 15-35 U/ml) greatly exceeded that of plasma (median 5.4, range 1.04-11.9 U/ml). Patients with atypical sporadic HUS had raised plasma mitogenic activity (median 9.35, range 0-35 U/ml, p less than 0.01). Both plasma and serum from children with the typical epidemic form of HUS had low or undetectable mitogenic activity (median for plasma 1.0, range 0-5.9 U/ml, p less than 0.001; median for serum 1.85, range 0-23.8 U/ml, p less than 0.005). These low concentrations in typical epidemic HUS were associated with the presence of an inhibitor of cell growth. The results suggest that there is intravascular release of platelet mitogens in atypical sporadic HUS and that these mitogens may therefore be mediators of the vascular proliferative lesions.

Purification and characterization of vaccinia virus growth factor.

A growth factor detected in the medium of vaccinia-virus-infected cells was purified to homogeneity. Sequence analysis shows it to be a processed form of a polypeptide encoded in the vaccinia virus genome which is related to epidermal growth factor (EGF) and alpha-transforming growth factor (alpha TGF). The amino terminus of the processed vaccinia virus growth factor (VVGF) begins at residue 20 of the primary translation product, indicating a signal sequence has been removed. The amino acid composition of purified VVGF predicts the carboxyl terminus is at, or near, residue 96, suggesting a transmembrane sequence has also been removed from secreted VVGF, which is, therefore, approximately 77 amino acids. VVGF, unlike EGF or alpha TGF, is glycosylated. VVGF binds to the EGF receptor and stimulates its autophosphorylation, suggesting that vaccinia virus has acquired sequences encoding a growth factor that may allow it to subvert EGF receptor-dependent functions.