CD26/DPPIV and response to hepatitis B vaccination

The prevention of hepatitis B is important, since it is responsible for significant morbidity and mortality around the world. Unfortunately, hepatitis B vaccine does not always induce protective immunity. The lack of immune response to vaccine (non-responders) can depend on individual characteristics. The objective of this study was to correlate the CD26/DPPIV cellular expression and DPPIV serum activity with HBV vaccine response and its possible role as an indicator of immune competence acquisition. We also determined the cellular expression of CD3, CD19, CD56 and CD25 in peripheral blood T lymphocytes. Blood samples were obtained from 28 healthy human volunteers who were enrolled with a vaccination program. There were "responders" (RM = 13) and "non-responders" (NRM = 15), after vaccination. The lymphocyte populations were identified by flow cytometry. DPPIV serum activity was measured fluorimetrically. CD26 expression in responders (55.9 +/- 7.7%) versus in non-responders (51.9 +/- 7.0%) did not show a significant difference. The DPPIV serum activity in responders compared to in non-responder subgroup (59.9 +/- 8.4/50.3 +/- 10.6U/L) showed, however, a significant difference (P < 0.05). The expression of CD3, CD19 and CD56 on peripheral lymphocytes was similar between responders and non-responders. The expression of CD3CD26 (52.2 +/- 8.6%) and CD3CD25 (10.9 +/- 3.8%) in responders versus the expression of CD3CD26 (48.0 +/- 5.7%) and CD3CD25 (8 +/- 4.6%) in non-responders did not show statistically significant difference. CD25 referred as a marker of T lymphocyte activation was increased in responders (15.8 +/- 4.5%) versus in non-responders (10.1 +/- 4.8%), showing a significant difference (P = 0.003). It was, however, impossible to demonstrate an increase in CD3CD25 and CD3CD26 in the responder subgroup. This suggests that different lymphocyte subsets other than T cells are implicated in the response to hepatitis B vaccination

Virtual laboratories in (bio)chemical engineering education

In the last decades, Information and Communications Technologies (ICT) have been promoting the creation and adoption of new learning and teaching styles. Virtual laboratories, by overcoming some limitations of conventional hands-on experiments, have been adopted as a complement or in substitution of laboratory sessions. This paper describes the design and implementation of two virtual labs for biochemical engineering education intended for students at the BSc degree. One of the virtual labs is intended to fully replace the hands-on experiment and consists on the determination of the correlation between oxygen transfer rate, aeration rate and agitation power in a reactor. The other virtual lab consists on the determination of the residence time distribution (RTD) in continuous stirred tanks series and was implemented to support the physical experiments rather than replacing them. The virtual labs provide the students a learning platform covering the fundamentals underlying the experiment, its pre-visualization and simulation. The effectiveness of the implemented system was evaluated through direct experimentation and survey (through questionnaires) with students taking the chemical technology lab course. For the RTD virtual Lab, and based on specific learning outcomes, teachers could assess significant improvement in students’ performance in the lab and also a more thorough discussion of the results in the reports. The survey results show that, in average, considering the two virtual labs and several classes, 93% of the students consider the virtual labs of great utility.Universidade do Minho (UM) - “Programa Qualidade

Virtual laboratories in (bio)chemical engineering education

"Qualidade” of the Universidade do Minho

Selective enzyme-mediated extraction of capsaicinoids and carotenoids from chili guajillo puya (Capsicum annuum L.) using ethanol as solvent

The selective extraction of capsaicinoids and carotenoids from chili guajillo “puya” flour was studied. When ethanol was used as solvent, 80% of capsaicinoids and 73% of carotenoids were extracted, representing an interesting alternative for the substitution of hexane in industrial processes. Additionally, when the flour was pretreated with enzymes that break the cell wall and then dried, extraction in ethanol increased to 11 and 7% for carotenoid and capsaicinoid, respectively. A selective two-stage extraction process after the treatment with enzymes is proposed. The first step uses 30% (v/v) ethanol and releases up to 60% of the initial capsaicinoids, and the second extraction step with industrial ethanol permits the recovery of 83% of carotenoids present in the flour

Identification of Sinorhizobium (Ensifer) medicae based on a specific genomic sequence unveiled by M13-PCR fingerprinting

A collection of nodule isolates from Medicago polymorpha obtained from southern and central Portugal was evaluated by M13-PCR fingerprinting and hierarchical cluster analysis. Several genomic clusters were obtained which, by 16S rRNA gene sequencing of selected representatives, were shown to be associated with particular taxonomic groups of rhizobia and other soil bacteria. The method provided a clear separation between rhizobia and co-isolated non-symbiotic soil contaminants. Ten M13-PCR groups were assigned to Sinorhizobium (Ensifer) medicae and included all isolates responsible for the formation of nitrogen-fixing nodules upon re-inoculation of M. polymorpha test-plants. In addition, enterobacterial repetitive intergenic consensus (ERIC)-PCR fingerprinting indicated a high genomic heterogeneity within the major M13-PCR clusters of S. medicae isolates. Based on nucleotide sequence data of an M13-PCR amplicon of ca. 1500 bp, observed only in S. medicae isolates and spanning locus Smed_3707 to Smed_3709 from the pSMED01 plasmid sequence of S. medicae WSM419 genome’s sequence, a pair of PCR primers was designed and used for direct PCR amplification of a 1399-bp sequence within this fragment. Additional in silico and in vitro experiments, as well as phylogenetic analysis, confirmed the specificity of this primer combination and therefore the reliability of this approach in the prompt identification of S. medicae isolates and their distinction from other soil bacteria. [Int Microbiol 2009; 12(4):215-225

Hemostatic dressings made of oxidized bacterial nanocellulose membranes

Surgicel® (regenerated oxidized cellulose) is a bio-absorbable hemostatic material widely applied to prevent surgery-derived adhesions. Some critical issues have been reported associated with this biomaterial, which we aimed to overcome by producing bacterial nanocellulose (BNC) membranes with hemostatic activity, through electrochemical oxidation using the tetramethylpiperidine-1-oxyl (TEMPO) radical. Samples were characterized by FTIR, NMR, SEM, XRD and their degree of polymerization. The oxidation degree was evaluated by titration of the carboxyl groups and the hemostatic behavior by whole-blood-clotting assays. In vitro and in vivo biodegradability of oxidized BNC membranes were evaluated and compared with that of Surgicel®. The oxidation degree increased from 4% to 7% and up to 15%, corresponding to an applied charge of 400, 700 and 1200 Coulombs, respectively. The oxidized BNC preserved the crystallinity and the 3D nano-fibrillar network, and demonstrated hemostatic activity, although not as effective as that of Surgicel®. In vivo assays demonstrated that the oxidized membranes did not induce an inflammatory response, revealing a good biocompatibility. However, non-degraded oxidized BNC was still detected at the implantation site after 56 days.This work was supported by the Fundação para a Ciência e Tecnologia (FCT), under the project BioTecNorte operation (NORTE01-0145-FEDER-000004), with funding by the European Regional Development Fund under the scope of Norte2020-Programa Operacional Regional do Norte. The authors gratefully give thanks to the project NORTE-08-5369-FSE-000012, with financial support of ESF—European Social Fund, under the scope of Norte2020—Programa Operacional Regional do Norte; and to UME-UTAD for the XRD analysis.info:eu-repo/semantics/publishedVersio

Bacterial cellulose as a support for the growth of retinal pigment epithelium

The feasibility of bacterial cellulose (BC) as a novel substrate for retinal pigment epithelium (RPE) culture was evaluated. Thin (41.6 ± 2.2 m of average thickness) and heatdried BC substrates were surface modified via acetylation and polysaccharide adsorption, using chitosan and carboxymethyl cellulose. All substrates were characterized according to their surface chemistry, wettability, energy, topography and also regarding their permeability, dimensional stability, mechanical properties and endotoxin content. Then, their ability to promote RPE cell adhesion and proliferation in vitro was assessed. All surface-modified BC substrates presented similar permeation coefficients with solutes of up to 300 kDa. Acetylation of BC decreased its swelling and the amount of endotoxins. Surface modification of BC greatly enhanced the adhesion and proliferation of RPE cells. All samples showed similar stress-strain behavior; BC and acetylated BC showed the highest elastic modulus, but the latter exhibited a slightly smaller tensile strength and elongation at break as compared to pristine BC. Although similar proliferation rates were observed among the modified substrates, the acetylated ones showed higher initial cell adhesion. This difference may be mainly due to the moderately hydrophilic surface obtained after acetylation.The authors acknowledge the Portuguese Foundation for Science and Technology (FCT, Portugal) for the financial support provided by the Research Grants SERH/BD/63578/2009, SFRH/BD/64901/2009, SFRH/BPD/64958/2009, and SFRH/BPD/63148/2009 for S.G., J.P., J.P.S., and V.S., respectively. The authors also acknowledge the Projects PEst-OE/EQB/LA0004/2013, PEst-OE/EQB/LA0023/2013, PTDC/BBB-BQB/2450/2012, and RECI/BBB-EBI/0179/2012 (Number: FCOMP-01-0124-FEDER-027462), cofunded by QREN, FEDER

On the Meaning of the String-Inspired Noncommutativity and its Implications

We propose an alternative interpretation for the meaning of noncommutativity of the string-inspired field theories and quantum mechanics. Arguments are presented to show that the noncommutativity generated in the stringy context should be assumed to be only between the particle coordinate observables, and not of the spacetime coordinates. Some implications of this fact for noncomutative field theories and quantum mechanics are discussed. In particular, a consistent interpretation is given for the wavefunction in quantum mechanics. An analysis of the noncommutative theories in the Schr\"odinger formulation is performed employing a generalized quantum Hamilton-Jacobi formalism. A formal structure for noncommutative quantum mechanics, richer than the one of noncommutative quantum field theory, comes out. Conditions for the classical and commutative limits of these theories have also been determined and applied in some examples.Comment: References, comments, and footnotes are included; some changes in section