Background Owing to its remarkable mechanical properties that surpass the plant-based cellulose, bacterial cellulose production has been targeted for commercialization during the last few years. However, the large-scale production of cellulose is generally limited by the slow growth of producing strains and low productivity which ultimately makes the commercial production of cellulose using the conventional strains non cost-effective. In this study, we developed a novel plasmid-based expression system for the biosynthesis of cellulose in E.coli DH5α and assessed the cellulose productivity relative to the typically used E.coli BL21 (DE) expression strain. Results No production was detected in BL21 (DE3) cultures upon expression induction; however, cellulose was detected in E.coli DH5α as early as 1 h post-induction. The total yield in induced DH5α cultures was estimated as 200 ± 5.42 mg/L (dry weight) after 18 h induction, which surpassed the yield reported in previous studies and even the wild-type Gluconacetobacterxylinum BRC5 under the same conditions. As confirmed with electron microscope micrograph, E.coli DH5α produced dense cellulose fibers with ~ 10 μm diameter and 1000–3000 μm length, which were remarkably larger and more crystalline than that typically produced by G.hansenii. Conclusions This is the first report on the successful cellulose production in E.coli DH5α which is typically used for plasmid multiplication rather than protein expression, without the need to co-express cmcax and ccpAx regulator genes present in the wild-type genome upstream the bcs-operon, and reportedly essential for the biosynthesis.

The present study was conducted to evaluate the chemical composition, antioxidant activity and hypoglycemic effects of whole kumquat (Ku) powder in diabetic rats fed a high-fat-high-cholesterol (HFHC) diet. The antioxidant activities were evaluated using stable 1,1-diphenyl 2-picrylhydrazyl (DPPH) free radical scavenging method, 2,2´-azinobis (3-ethyl benzo thiazoline-6-sulphonic acid) radical cation (ABTS) and Ferric reducing antioxidant power (FRAP). Total phenolic content was (51.85 mg GAE/g) and total flavonoid content was (0.24 mg Cateachin Equivalent, CE/g). DPPH and ABTS values were 3.32 and 3.98 mg Trolox equivalent (TE)/g where FRAP value was 3.00 mM Fe2+/kg dry material. A total of 90 albino rats were used in the present study. Rats group were as follows: normal diet; normal treated (2, 4, and 6% Ku.), diabetic rats (non-treated), diabetic + HFHC diet (non-treated), HFHC (non-treated), Diabetic (treated), HFHC (treated) and Diabetic + HFHC (treated). The diets were followed for 8 weeks. Blood samples were collected at the end of the experiment. Serum glucose was recorded and thyroid hormones (T4, Thyroxine and T3, Triiodothyronine) were conducted. Diet supplemented with Kumquat at different concentrations have a hypoglycemic effect and improve the thyroid hormones of both diabetic rats and HFHC diabetic rats.

The present work aimed at 1) characterization of the E1 and E2 proteins (HCV-E) from an Egyptian hepatitis C virus genotype 4a (HCV-4a) isolate at the molecular and immunological level, 2) in silico identification of the B- and T-cell epitopes responsible for the immunogenicity of HCV-E, and 3) evaluation of the diagnostic potential of both the recombinant HCV-E and antibodies raised using mammalian expression constructs encoding the protein. The region encoding the E1 and E2 proteins was amplified by RT-PCR from RNA isolated from blood of a human infected with HCV-4 and cloned into the pSC-TA plasmid, and the sequence was verified and used to construct a neighbor-joining phylogenetic tree. The translated nucleotide sequence was used to predict the HCV-E secondary structure using the PREDICT-PROTEIN server and PSI-PRED. A 3D model of HCV-E was generated using the online tool 3Dpro. B- and T-cell epitopes were predicted using the online tools BCPred and Epijen v1.0, respectively. The HCV-E-encoding sequence was later subcloned into the mammalian expression plasmid pQE, and the constructs that were generated were used to immunize mice in the absence and presence of adjuvants of plant origin. The maximum sequence identity obtained by nucleotide and protein BLAST analysis with previously published HCV-E sequences was 85 and 77 %, respectively. The B-cell epitope CFTPSPVVV at position 203 and the T-cell epitope ALSTGLIHL at position 380 were found to be highly conserved among all HCV genotypes. Both ELISA and Western blotting experiments on crude and purified recombinant HCV envelope proteins using mouse antisera raised using the HCV-E mammalian expression construct confirmed the specific antigenicity of the expressed protein. The antibodies raised in mice using the HCV-E-encoding construct could efficiently capture circulating antigens in patients' sera with good sensitivity that correlated with liver enzyme levels (r = 0.4052, P < 0.0001 for ALT; r = -0.5439, P = 0.0019 for AST). Moreover, combining the HCV-E-encoding construct with extracts prepared from Echinacea purpurea and Nigella sativa prior to immunizing mice significantly (P < 0.05) increased both the humoral (14.9- to 20-fold increase in antibodies) and the cellular (CD4(+) and cytotoxic CD8(+)- T lymphocytes) responses compared to mice that received the DNA construct alone or PBS-treated mice. Both recombinant HCV-E protein preparations and antibodies raised using the HCV-E-encoding mammalian expression construct represent useful diagnostic tools that can report on active HCV infection. Also, the immunostimulatory effects induced by the two plant extracts used at the cellular and humoral level highlight the potential of natural products for inducing protection against HCV infection. The neutralizing capacity of the induced antibodies is a subject of future investigations. Furthermore, the predicted B- and T-cell epitopes may be useful for tailoring future diagnostics and candidate vaccines against various HCV genotypes.

This study aimed to evaluate the prognostic value of baseline macrophage inflammatory protein (MIP)-1β/IL12p40 ratio for antiviral treatment outcome in HCV genotype 4 patients. METHODS: Sera of 450 treatment-naïve chronic HCV patients and 50 healthy individuals were collected. Liver transaminases, total bilirubin and albumin were biochemically tested, viral RNA was quantified, and circulating MIP-1β and IL-12p40 were estimated using human anti-MIP-1β and IL-12p40 antibodies in Sandwich ELISA. RESULTS : No difference was observed in the baseline chemokines levels between responders and relapsers, but the later had a significantly higher MIP-1β/IL-12p40 ratio (P< 0.0001). Multivariate regression analysis of baseline characteristics showed that gender, age, viral load, albumin level and chemokine ratios can significantly predict treatment outcome (P= 0.0114, 0.0095, 0.042, 0.0004 and < 0.0001; respectively). Accordingly, a predictive threshold of baseline chemokine ratio was calculated and it showed an AUC of 0.6917 (P= 0.0108; 95% CI: 0.5566 to 0.8268). The calculated threshold for predicting virologic response was 8.245, with positive and negative predictive values of 92.98% and 100%; respectively. The chemokine ratios had significant correlations with liver transaminases in treated groups whether pre or post-treatment. CONCLUSION: Baseline MIP-1β/IL-12p40 ratio represents a non-invasive prognostic biomarker that would provide shorter treatment duration and minimizes the emergence of drug-resistant variants in HCV genotype 4-patients.

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