Epoxy Functionalized Carboxymethyl Dextran Magnetic Nanoparticles for Immobilization of Alcohol Dehydrogenase.

Microbial inhibition of carboxymethyl dextran (CMD) magnetic nanoparticles (MNPs) was investigated on two different bacterial cultures, Escherichia coli and Staphylococcus aureus, where inhibition properties of CMD-MNPs were confirmed, while uncoated MNPs exhibited no inhibition properties. To such CMD-MNPs, enzyme alcohol dehydrogenase (ADH) from Saccharomyces cerevisiae was immobilized. Later on, CMD-MNPs were functionalized, using an epoxide cross-linker epichlorohydrin (EClH) for another option of ADH immobilization. Residual activities of immobilized ADH onto epoxy functionalized and non-functionalized CMD-MNPs were determined. Effect of cross-linker concentration, temperature of immobilization and enzyme concentration on residual activities of immobilized ADH were determined, as well. With optimal process conditions (4% (v/v) EClH, 4 °C and 0.02 mg/mL of ADH), residual activity of immobilized ADH was 90%. Such immobilized ADH was characterized using FT-IR, SEM and DLS analysis.

Protein Release from Biodegradable Poly(ε-Caprolactone)-Chitosan Scaffolds Prepared in scCO2.

To study the release patterns of protein bovine serum albumin (BSA), porous poly(ε-caprolactone)-chitosan scaffolds with entrapped BSA were fabricated by using supercritical CO2 for its potential use in tissue engineering applications. An emulsion, consisting of a polymer-solvent solution and buffer protein solution was saturated with scCO2 at 12 MPa and 37 °C and then rapidly depressurized through a release valve causing bubble nucleation and precipitation of the composite material. The controlled total protein release from biodegradable poly(α-caprolactone) with 5% chitosan (w/w) scaffolds was assessed by Bradford protein assay. After 16 to 20 days of protein release testing, 58.8% of the protein was released from composite with PCL (Mw = 10,000 g/mol) and 43.9% from composite with PCL (Mw = 60,000 g/mol). Preliminary studies for characterization of the prepared composite biomaterials using FTIR spectra, ESEM photo analysis and DSC analysis have been carried out.

Predictive value of ABCB1 polymorphisms G2677T/A, C3435T, and their haplotype in small cell lung cancer patients treated with chemotherapy.

PURPOSE: Multiple drug resistance limits the efficacy of numerous cytotoxic drugs used in the treatment of small cell lung cancer (SCLC). The drug efflux protein ATP-binding cassette transporter B1 (ABCB1) has an important role in this process, and its gene variability may affect chemotherapy outcomes. PATIENTS AND METHODS: This study aimed to evaluate the associations between ABCB1 polymorphisms G2677T/A, C3435T, and their haplotype with progression-free survival (PFS) and overall survival (OS) in 177 SCLC patients treated with cisplatin-etoposide or cyclophosphamide-epirubicin-vincristine chemotherapy. To determine the ABCB1 genotype, allelic specific TaqMan(®) probes were used in a RT-PCR . RESULTS: Patients carrying the G2677T/A TT + TA + AA genotypes (24 %) or the C3435T CT + TT genotypes (72 %) or the 2677T/A-3435T haplotype (40 %) had a longer PFS (Cox regression, P = 0.052, 0.037 and 0.037, respectively); these associations persisted also in multivariate analyses (Cox regression, P = 0.028, 0.037 and 0.030, respectively). Moreover, patients with the C3435T CT + TT genotypes had a longer OS both in univariate and multivariate analysis (Cox regression, P = 0.022 and 0.028, respectively). A trend toward longer OS was noted for the 2677T/A-3435T haplotype (Cox regression, P = 0.051), but its independent value was not confirmed (Cox regression, P = 0.071). CONCLUSIONS: Our study reported a possible predictive value of ABCB1 polymorphisms G2677T/A, C3435T, and their haplotype for longer PFS and OS in Caucasian SCLC patients treated with chemotherapy. However, to be implemented into routine clinical practice, ABCB1 polymorphisms require further validation.