[Effects of Poly I:C in inducing growth inhibition and apoptosis of human hepatocellular carcinoma cells].

OBJECTIVE: To explore the effect and mechanism of Poly I:C in inducing growth inhibition and apoptosis of human hepatocellular carcinoma SMMC-7721 cells. METHODS: SMMC-7721 cells were treated with different doses of Poly I:C for 24, 48, and 72 h, and the cell growth inhibition rate was analyzed with CCK-8 assay. The cell cycle and the apoptosis were analyzed using flow cytometry with Annexin-V and PI staining, and quantitative RT-PCR analysis were used to detect the expression of TLR3, TRIF, and IFN-beta mRNA in cells. RESULTS: In the cells exposed to Poly I:C at low, moderate, and high doses, the inhibitory rates was the highest in high-dose Poly I:C group, and at a given Poly I:C dose, prolonged exposure resulted in significantly increased cell growth inhibition rate (P<0.05). Flow cytometry showed that Poly I:C induced cell apoptosis in a time- and dose-dependent manner and significantly increased the percentage of G1-phase cells as compared with that in the control group. The mRNA level of TLR3, TRIF, and IFN-beta were also increased following Poly I:C treatment in comparison with the control group. CONCLUSION: Poly I:C can induce significant growth inhibition and apoptosis of SMMC-7721 cells in a dose- and time-dependent manner possibly by causing cell cycle arrest and TLR3 signaling pathway activation that leads to IFN-beta production and cell apoptosis.

Postnatal lung mechanics, lung composition, and surfactant synthesis after tracheal occlusion vs prenatal intrapulmonary instillation of perfluorocarbon in fetal rabbits.

BACKGROUND/PURPOSE: Fetal tracheal occlusion (TO) accelerates lung growth but decreases surfactant production. We have previously shown that instillation of perfluorooctylbromide (PFOB) into fetal rabbit lungs leads to lung growth similar to TO. This study compares neonatal lung mechanics and surfactant production after prenatal intrapulmonary PFOB instillation vs TO. METHODS: In each of 18 pregnant rabbits on gestational day 27, sets of 4 fetuses underwent either (1) intrapulmonary instillation of 1 mL PFOB, (2) TO, (3) instillation of 1 mL 0.9% NaCl (saline), and (4) hysteroamniotomy without fetal manipulation (control). Fetuses were born by cesarean delivery after 48 hours. Fetuses of 12 rabbits were mechanically ventilated for 15 minutes to evaluate lung compliance and airway resistance. Pulmonary surfactant protein B (SP-B) was quantified by immunohistochemistry in fetuses of the remaining 6 rabbits. RESULTS: Compliance was decreased in the TO group after cesarean delivery (0.33 +/- 0.13 mL/cm H2O) compared with PFOB (0.59 +/- 0.12 mL/cm H2O), saline (0.50 +/- 0.12 mL/cm H2O), and control (0.52 +/- 0.10 mL/cm H2O) fetuses. Mean fetal lung to body weight ratio was higher in TO and PFOB fetuses compared with saline and control. Higher water content and lower numbers of surfactant protein B-positive cells were found in the TO-treated fetuses. CONCLUSIONS: Both prenatal intrapulmonary instillation of PFOB and TO accelerate lung growth, but TO is associated with decreased postnatal lung compliance, possibly influenced by decreased surfactant production and increased fluid retention. Conversely, instillation of PFOB preserved lung compliance and surfactant synthesis.

[A study on the relationship between interleukin-10 promoter polymorphism and autoimmune liver disease].

OBJECTIVE: To investigate whether three biallelic polymorphisms at the position -592, -819 and -1082 in the promoter region of the IL-10 gene were associated with the incidence of autoimmune liver disease. METHODS: The IL-10 -592 and IL-10-1082 polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphisms analysis (PCR-RFLP), while polymerase chain reaction- sequence specific primer (PCR-SSP) assay was used to detect IL-10 -819 polymorphisms. RESULTS: Among 54 Chinese patients with AIH or 77 Chinese patients with PBC versus healthy controls, the frequency of AA, GA genotypes at IL-10 gene promoter -1082 position was 87.0% or 83.1% versus 90.0%, 13.0% or 16.9% versus 10.0%, respectively (P > 0.05), the GG genotype in Chinese populations is absent; the frequency of CC, CT, TT genotypes at IL-10 gene promoter -819 position was 11.11% or 9.1% versus 8.1%, 44.4% or 53.3% versus 45.0%, 44.4% or 37.7% versus 46.9%, respectively (P > 0.05); the frequency of CC, CA, AA genotypes at IL-10 gene promoter -592 position was 4.9% or 14.3% versus 10.0%, 51.2% or 53.3% versus 51.9%, 43.9% or 32.5% versus 38.1%, respectively (P > 0.05). No alleles differed significantly in each groups. CONCLUSION: There were no association between IL-10 gene polymorphisms and autoimmune liver disease

Pulmonary effects of gastroschisis in a fetal rabbit model.

Respiratory insufficiency is a significant cause of mortality and morbidity among infants with anterior abdominal wall defects (AWD). The aim of this study was to evaluate the pulmonary effects in a fetal rabbit model where gastroschisis was induced at midgestation. Gastroschisis (GAS) was created in 20 rabbit fetuses on day 22 or 23 of gestation (pseudoglandular phase; term = 31-32 days). The amniotic sacs of 13 fetuses were subjected to hysterotomy and amniotomy only (HYST), while 13 underwent a sham laparotomy which was immediately closed by sutures (SHAM). Eleven nonoperated littermates served as internal controls (CTR). Fetuses were harvested by cesarean section on day 31 of gestation prior to respiration. Pulmonary response was evaluated by left lung to body weight ratio (LWBWR), airway morphometry, and density of type II pneumocytes, as evaluated by the number of surfactant protein B-positive cells. Fetuses from the GAS group had significantly lower body weights than did CTR (P = 0.0129). Of these fetuses, 27% were growth-restricted, i.e., with a body weight under the 10th percentile of the CTR population. There were no differences in left lung weight and LWBWR among the GAS and CTR groups. Moreover, the GAS group had similar alveolar size, alveolar wall thickness, and type II cell density as CTR fetuses. Only mean terminal bronchiolar density (MTBD), which is inversely related to the alveolar space, was slightly increased in the GAS group, but without reaching significance (P = 0.0821). No effect on lung growth and maturation could be demonstrated in this study.

[The preparation of human anti-HBs Fab fragment by bioengineering technique].

AIM: To prepare human anti-HBs Fab by bioengineering technique. METHODS: The specific human anti-HBs Fab gene screened from combinatorial library was cloned into plasmid pBAD/g IIIA, then positive clone was transformed into E.coli Top10. After the fermentation and expression processes, the soluble Fab fragment in the periplasm were purified by Ni-NTA-agarose affinity chromatography,and the inclusion bodies were in turn denatured, solubilized, purified and renatured. The specificity of Fab protein was confirmed by Western blot, and binding activity to HBsAg was verified by Dot blot. RESULTS: The quantity of soluble Fab protein purified from periplasm with Ni-NTA-Agarose which possessed good specificity as well as excellent binding activity to antigens was up to 80 mg per liter, but the biologically active protein acquired after renaturation of the inclusion bodies was quite small. CONCLUSION: Using pBAD/g IIIA-Top10 expression system, the soluble Fab protein with biological activity could be produced from periplasm of the E.coli Top10, and the strategy is available to prepare human anti-HBsAg Fab fragments in large quantity by gene engineering technique.