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Crude oil spills seriously harm the ocean environment and endanger the health of various animals and plants. In the present study, a totally biodegradable polymer, poly(L-lactic acid) (PLLA), was employed to fabricate highly porous oil absorbent nanofibrous materials by using a combination of electrospinning technique and subsequent acetone treatment. We systematically investigated how the electrospinning parameters affected formation of the porous structure of PLLA nanofibers and demonstrated that PLLA nanofibers with decreased and uniform diameter and improved porosity could be rapidly prepared by adjusting solution parameters and spinning parameters. We also demonstrated that the acetone treatment could obviously enhance the pore diameter and specific surface area of as-optimized electrospun PLLA nanofibers. The acetone treatment could also improve the hydrophobic property of as-treated PLLA nanofiber membranes. All these led to a significant increase in oil absorption performance. Through our research, it was found that the oil absorption of PLLA nanofiber membrane increased by more than double after being treated with acetone and the oil retention rate was also improved slightly.

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BACKGROUND: Neutrophil-to-lymphocyte ratio (NLR) is crucial for the incidence and mortality of various tumors. However, little is known on NLR and its association with prognosis in advanced tumors. Here we performed a meta-analysis to establish the prognostic significance of pretreatment blood NLR for advanced tumors. METHODS: A systematic literature search through April 2016 was performed to evaluate the association between pretreatment blood NLR and overall survival (OS) or progression-free survival (PFS) in patients with advanced tumors. Data were extracted from studies reporting hazard ratios (HRs) and 95% confidence interval (CI) and pooled using the Mantel-Haenszel random-effect model. RESULTS: Sixty-six studies with a total of 24536 individuals were included in the meta-analysis. Pooled analyses revealed that elevated pretreatment NLR was associated with worse OS (HR 1.70, 95% CI 1.57-1.84, P<0.001) and PFS (HR 1.61, 95% CI 1.42-1.82, P<0.001) in advanced tumors. Subgroup analysis stratified by tumor type demonstrated that pancreatic cancer patients with high pretreatment NLR had the worst OS (HR 1.94, 95% CI 1.55-2.54, P<0.001) and colorectal cancer with the worst PFS (HR 1.74, 95% CI 1.04-2.90, P<0.001). When stratified by cut-off value for NLR, we found that cut-off value being five indicated the worst PFS (HR 2.23, 95% CI 1.54-3.23, P=0.019). CONCLUSIONS: Overall, high pretreatment blood NLR could be an adverse prognostic indicator for advanced tumor. Large-scale prospective studies investigating its survival outcomes in specific cancer type are strongly advocated.

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Graphene oxide(GO)-activated carbon felt(ACF)(GO-ACF) composite was prepared by an electrophoretic deposition and subsequent thermal annealing. The structures of GO and GO-ACF were characterized by FT-IR, Raman spectra and XPS. The adsorption capacities for U(VI) from aqueous solution of ACF and GO-ACF were compared. The essential factors affected U(VI) adsorption such as initial pH, contact time and temperature were investigated. The adsorption is highly dependent on the solution pH. In addition, the adsorption isotherm and thermodynamics were investigated. The adsorptions of U(VI) from aqueous solution on GO-ACF were fitted to the Langmuir and, Freundlich adsorption isotherms. The adsorption of U(VI) could be well-described by Langmuir. The adsorption of U(VI) on ACF is remarkably improved by GO covalently bonding with ACF. The maximum sorption capacity of GO-ACF for U(VI) was evaluated to be 298 mg/g at pH 5.5, much higher than that of ACF (173 mg/g), suggesting the carboxyl functional groups of GO-ACF playing important roles in the sorption. Thermodynamic parameters further show that the sorption is an endothermic and spontaneous process. GO-ACF is a powerful promising sorbent for the efficient removal of U(VI) from aqueous solutions.

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BACKGROUND: To express recombinant non-structural protein 3 of hepatitis C virus (HCV) in E. coli. METHODS: The non-structural 3 (NS3) region DNA fragment of HCV was amplified by polymerase chain reaction (PCR) and inserted into inducible proeukaryotic expressive vector pET 30C(+)at Bam H1/EcoR1 sites. The competent BL21 (DE3) E.coli was transformed, and then cultured and induced with IPTG. The expressed HCV NS3 protein was confirmed with ELISA and dot blot hybridization using HCV NS3-specific single chain Fv (ScFv) antibody. RESULTS: 1 893 bp DNA fragment of HCV NS3 coding region was amplified by PCR technique. HCV NS3 expressive vector pET-NS3 was constructed. After transformation with pET-NS3 and induction with IPTG, recombinant HCV NS3 protein was expressed and confirmed by specific ELISA and dot blot hybridization. CONCLUSIONS: The recombinant HCV NS3 can be expressed in E. coli.

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OBJECTIVE: To develop a bacteria expression system to produce the fusion protein of humanized anti-HBsAg scFV and interferon-alpha. METHODS: The expression vector was constructed after cleaving the plasmids harboring the humanized anti-HBsAg scFv and interferon alpha respectively and ligating to linearized pET22b subsequence. The expression of fusion protein in E.coli was analyzed by SDS-PAGE. The binding activity and antiviral activity of the fusion protein was characterized by competing inhibition test and cytopathic effect reduction. RESULTS: The plasmid harboring the in frame arranged fusion gene was constructed and identified. After induction for 12h, a new band close to 4.5 10(4) was observed using SDS-PAGE. Results of competing ELISA and cytopathic effect reduction showed the fusion protein retained its specific binding activity and antiviral activities. CONCLUSIONS: The construction and expression of the fusion gene of humanized anti-HBsAg scFv and interferon in E.coli are successful.

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OBJECTIVE: To clone the unknown gene of hepatocyte protein interacting with hepatitis C virus core protein. METHODS: Using the yeast dual hybrid system 3, bait plasmids of hepatitis C virus core were constructed. After identifying hepatitis C virus core protein that could stably expressed in AH109 yeast strains, we performed yeast two hybrid by mating AH109 with Y187 that transformed with liver cDNA library plasmids pACT2 and then plated on quadrople dropout (QDO) medium and assayed for alpha-gal activity. The genes of yeast colonies that could grow on QDO and had alpha-gal activity were sequenced. RESULTS: Among the 30 positive colonies, we blasted the gene of the sixth colony; we coined human hepatitis C virus binding protein 6(Hu Hcbp6) with Genbank, realized that the Hu Hcbp6 shares as much as 98% homology with two cDNA without knowing functions. We have proved that Hu Hcbp6 could interact with hepatitis C virus core protein. CONCLUSIONS: Hepatitis C virus core binding protein (Hu Hcbp 6 Genbank number: AY032594) was successfully cloned and identified. The study partly paved the way for investigating physiological function of the Hu Hcbp6.

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AIM:To develop a culture mode providing durable biomaterials with high yields and activities used in bioartificial liver.METHODS:Hepatocytes were isolated from a whole pig liver by Seglen s method of orthotopic perfusion with collagenase. In culture on microcarriers, primary porcine hepatocytes were inoculated at a concentration of 5center dot10(7)/mL into the static culture systems containing 2g/L Cytodex-3, then supplemented with 100mL/L fetal calf serum (FCS) or 100mL/L porcine portal vein serum (PPVS) respectively. In spheroidal aggregate culture hepatocytes were inoculated into 100mL siliconized flasks at a concentration of 5.0center dot10(6)/mL.RESULTS:In culture on microcarriers hepatocytes tended to aggregate on Cytodex-3 obviously after being inoculated. Typical multi-cellular aggregated spheroids could be found in the two systems 24h-48h after hepatocytes were cultured. The morphological charact-eristics and synthetic functions were maintained for 5wk in FCS culture system and 8wk in PPVS culture system. In spheroidal aggregate culture about 80%-90% isolated hepatocytes became aggregated spheroids 24h after cultured in suspension and mean diameter of the spheroids was 100&mgr;m. The relationship among the hepatocytes resembled that in the liver in vivo. Synthetic functions of albumin and urea of the spheroids were twice those of hepatocytes cultured on monolayers.CONCLUSION:As high-yields and high-activity modes of culture on microcarriers or in spheroidal aggregate culture with portal vein serum are promising to provide biomaterials for bioartificial liver (BAL) efficiently.

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AIM:To improve the cultivation efficiency and yield of human liver cell line CL-1.METHODS:High-density cultivation of CL-1 on microcarriers was carried out with periodic observation of their growth and proliferation. The specific functions of human liver cell were also determined.RESULTS:Cells of CL-1 cell line grew well on microcarrier Cytodex-3 and on the 7th day the peak was reached. The amount of CL-1 cells was 2.13X10(8) and the total amount of albumin synthesis reached 71.23&mgr;g,urea synthesis 23.32mg and diazepam transformation 619.7ug respectively. The yield of CL-1 on microcarriers was 49.3 times that of conventional cultivation. The amounts of albumin synthesis, urea synthesis and diazepam transformation were 39.8 times, 41.6 times and 33.3 times those of conventional cultivation, respec-tively.CONCLUSION:The human liver cell line CL-1 can be cultivated to a high density with Cytodex-3 and has better biological functions. High-density cultivation of CL-1 on microcarriers can act as the biological material of bioartificial liver.