442 results match your criteria: "IBB-Institute for Biotechnology and Bioengineering[Affiliation]"

Removal of Ni(II) from aqueous solutions by an Arthrobacter viscosus biofilm supported on zeolite: from laboratory to pilot scale.

Bioresour Technol

August 2013

IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal.

This study discusses the retention of Ni(II) by Arthrobacter viscosus supported on zeolite 13 X in batch mode and in continuous mode, at laboratory scale and at pilot scale. The maximum adsorption capacities of 28.37, 20.

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Structural diversity of Aspergillus (section nigri) spores.

Microsc Microanal

October 2013

IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal.

The taxonomy of fungal species, similar to that of many other microorganisms, suffers frequent revisions due to the discovery of new species and to the development and gathering of characterization data and morphological information. Morpho-taxonomy helps in the identification of many species. This work presents the macro, micro-morphological, and spectral mass analyses for phenotypic characterization of 13 species of Aspergillus section Nigri, showing that the characterization of spores (conidia) by scanning electron microscopy can be used as a tool to discriminate key morphological characteristics and separate closely related fungi.

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Interactions between Lactobacillus crispatus and bacterial vaginosis (BV)-associated bacterial species in initial attachment and biofilm formation.

Int J Mol Sci

June 2013

Centre of Biological Engineering, IBB-Institute for Biotechnology and Bioengineering, University of Minho, Campus de Gualtar 4710-057, Braga, Portugal.

Certain anaerobic bacterial species tend to predominate the vaginal flora during bacterial vaginosis (BV), with Gardnerella vaginalis being the most common. However, the exact role of G. vaginalis in BV has not yet been determined.

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Evaluation of macroporous and microporous carriers for CHO-K1 cell growth and monoclonal antibody production.

J Microbiol Biotechnol

September 2013

IBB - Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal.

The emergence of microcarrier technology has brought a renewed interest in anchorage-dependent cell culture for high-yield processes. Well-known in vaccine production, microcarrier culture also has potential for application in other fields. In this work, two types of microcarriers were evaluated for small-scale monoclonal antibody (mAb) production by CHOK1 cells.

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Optimization of an automatic counting system for the quantification of Staphylococcus epidermidis cells in biofilms.

J Basic Microbiol

July 2014

IBB - Institute for Biotechnology and Bioengineering, University of Minho, Campus de Gualtar, Braga, Portugal; ICBAS-UP - Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Porto, Portugal.

Biofilm formation is recognized as the main virulence factor in a variety of chronic infections. In vitro evaluation of biofilm formation is often achieved by quantification of viable or total cells. However, these methods depend on biofilm disruption, which is often achieved by vortexing or sonication.

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Multivariate analysis applied to agglomerated macrobenthic data from an unpolluted estuary.

Mar Environ Res

January 2014

IBB-Institute for Biotechnology and Bioengineering, Center for Biological and Chemical Engineering, Instituto Superior Técnico (IST), Av. Rovisco Pais, 1049-001 Lisbon, Portugal.

We agglomerated species into higher taxonomic aggregations and functional groups to analyse environmental gradients in an unpolluted estuary. We then applied non-metric Multidimensional Scaling and Redundancy Analysis (RDA) for ordination of the agglomerated data matrices. The correlation between the ordinations produced by both methods was generally high.

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Poly(dimethyl siloxane) (PDMS) was surface-polymerized with poly(ethylene glycol)methacrylate (PEGMA) by surface-initiated atom transfer radical polymerization (SI-ATRP) in aqueous media at room temperature. Modification of the PDMS surface followed a three-step procedure: (i) PDMS surface hydroxylation by UV/ozone exposure, immediately followed by (ii) covalent attachment of the initiator, 1-trichlorosilyl-2-(chloromethylphenyl)ethane, onto the hydroxylated PDMS, via chemical vapor deposition; finally (iii) PDMS surface-polymerization of PEGMA by ATRP. Modified PDMS was characterized by water contact angle measurement, SEM, FTIR-ATR, and XPS.

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Proteomic approach to Pseudomonas aeruginosa adaptive resistance to benzalkonium chloride.

J Proteomics

August 2013

IBB - Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal.

Unlabelled: This study aimed to assess the membrane modifications in Pseudomonas aeruginosa after continuous exposure to increasing doses of benzalkonium chloride (BC). Two different concentrations were used, 0.9 and 12.

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Potential of human γD-crystallin for hair damage repair: insights into the mechanical properties and biocompatibility.

Int J Cosmet Sci

October 2013

IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057, Braga, Portugal; Department of Biology, Centre of Molecular and Environmental Biology (CBMA), Universidade do Minho, Campus de Gualtar, 4710-057, Braga, Portugal.

Objectives: The objective of this work was to develop a new strategy to physically 'repair' chemically damaged hair. Hence the human eye γD-crystallin, a protein from the superfamily characterized structurally by the Greek key motif, was studied. The human γD-crystallin was chosen based on the ability of proteins belonging to this superfamily to be involved in the coating of specific structures.

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Optimization of CO₂ bio-mitigation by Chlorella vulgaris.

Bioresour Technol

July 2013

IBB - Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal.

Biofixation of CO2 by microalgae has been recognized as an attractive approach to CO2 mitigation. The main objective of this work was to maximize the rate of CO2 fixation ( [Formula: see text] ) by the green microalga Chlorella vulgaris P12 cultivated photoautotrophically in bubble column photobioreactors under different CO2 concentrations (ranging from 2% to 10%) and aeration rates (ranging from 0.1 to 0.

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Combined effect of linezolid and N-acetylcysteine against Staphylococcus epidermidis biofilms.

Enferm Infecc Microbiol Clin

December 2013

IBB - Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Braga, Portugal; Department of Biotechnology, Federal University of São Carlos, São Carlos, São Paulo, Brazil.

Introduction: Staphylococcus epidermidis is an organism commonly associated with infections caused by biofilms. Biofilms are less sensible to antibiotics and therefore are more difficult to eradicate. Linezolid and N-acetylcysteine (NAC), have demonstrated to be active against gram-positive microorganisms.

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Bioreactor design for clinical-grade expansion of stem cells.

Biotechnol J

June 2013

Department of Bioengineering and IBB - Institute for Biotechnology and Bioengineering - Instituto Superior Técnico IST, Technical University of Lisbon, Lisboa, Portugal.

The many clinical trials currently in progress will likely lead to the widespread use of stem cell-based therapies for an extensive variety of diseases, either in autologous or allogeneic settings. With the current pace of progress, in a few years' time, the field of stem cell-based therapy should be able to respond to the market demand for safe, robust and clinically efficient stem cell-based therapeutics. Due to the limited number of stem cells that can be obtained from a single donor, one of the major challenges on the roadmap for regulatory approval of such medicinal products is the expansion of stem cells using Good Manufacturing Practices (GMP)-compliant culture systems.

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Polymeric nanoparticles have revealed very effective in transmucosal delivery of proteins. Polysaccharides are among the most used materials for the production of these carriers, owing to their structural flexibility and propensity to evidence biocompatibility and biodegradability. In parallel, there is a preference for the use of mild methods for their production, in order to prevent protein degradation, ensure lower costs and easier procedures that enable scaling up.

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Characterization of an estuarine environment by means of an index based on intertidal macrofauna.

Mar Pollut Bull

June 2013

IBB-Institute for Biotechnology and Bioengineering, Center for Biological and Chemical Engineering, Instituto Superior Técnico (IST), 1049-001 Lisbon, Portugal.

Macrobenthic intertidal assemblages from five Atlantic Iberian estuaries were analyzed to develop an estuarine index. An R-mode analysis revealed a close association between the isopod Cyathura carinata, the polychaete Hediste diversicolor and the bivalve Scrobicularia plana. Although these species are abundant in all the estuaries considered, they tend to be absent from sites at the marine and freshwater ends of the environmental gradient.

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Here, we evaluated a previously established peptide nucleic acid-fluorescence in situ hybridization (PNA-FISH) method as a new diagnostic test for Helicobacter pylori clarithromycin resistance detection in paraffin-embedded gastric biopsy specimens. Both a retrospective study and a prospective cohort study were conducted to evaluate the specificity and sensitivity of a PNA-FISH method to determine H. pylori clarithromycin resistance.

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Acoustic detection of cell adhesion on a quartz crystal microbalance.

Biotechnol Appl Biochem

March 2014

IBB-Institute for Biotechnology and Bioengineering, Centre for Molecular and Structural Biomedicine, University of the Algarve, Campus de Gambelas, Faro, Portugal.

An acoustic quartz crystal microbalance (QCM) was used to signal and follow the cell‑adhesion process of epithelial cells [human embryonic kidney(HEK) 293T and cervical cancer (HeLa) and fibroblasts [African Green Monkey kidney cells (COS-7)] onto gold surfaces. Cells were applied on the sensor and grown under serum-free and serum-supplemented culture media. The sensor resonance frequency (Δf) and motional resistance (ΔR) variations were measured during cell growth to monitor cell adhesion processes.

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Fluorescence in situ Hybridization method using Peptide Nucleic Acid probes for rapid detection of Lactobacillus and Gardnerella spp.

BMC Microbiol

April 2013

IBB - Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, Braga 4710-057, Portugal.

Background: Bacterial vaginosis (BV) is a common vaginal infection occurring in women of reproductive age. It is widely accepted that the microbial switch from normal microflora to BV is characterized by a decrease in vaginal colonization by Lactobacillus species together with an increase of Gardnerella vaginalis and other anaerobes. Our goal was to develop and optimize a novel Peptide Nucleic Acid (PNA) Fluorescence in situ Hybridization assay (PNA FISH) for the detection of Lactobacillus spp.

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In vitro and computational studies of transdermal perfusion of nanoformulations containing a large molecular weight protein.

Colloids Surf B Biointerfaces

August 2013

IBB - Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, 4710-057 Braga, Portugal.

Transdermal perfusion of a large protein is reported for the first time, using a nanoemulsion of bovine serum albumin (66kDa) of 160nm prepared by a solid-in-oil (S/O) process. Molecular dynamics simulations confirmed skin permeation by these formulations, with integration of the protein into the lipid bilayers. These results demonstrate the real possibility of delivering large proteins transdermally for a range of medical and cosmetic applications.

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Comparison of Yarrowia lipolytica and Pichia pastoris cellular response to different agents of oxidative stress.

Appl Biochem Biotechnol

May 2013

IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057, Braga, Portugal.

Yeast cells exposed to adverse conditions employ a number of defense mechanisms in order to respond effectively to the stress effects of reactive oxygen species. In this work, the cellular response of Yarrowia lipolytica and Pichia pastoris to the exposure to the ROS-inducing agents' paraquat, hydrogen peroxide, and increased air pressure was analyzed. Yeast cells at exponential phase were exposed for 3 h to 1 mM paraquat, to 50 mM H2O2, or to increased air pressure of 3 or 5 bar.

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The present study focuses on predicting the concentration of intracellular storage polymers in enhanced biological phosphorus removal (EBPR) systems. For that purpose, quantitative image analysis techniques were developed for determining the intracellular concentrations of PHA (PHB and PHV) with Nile blue and glycogen with aniline blue staining. Partial least squares (PLS) were used to predict the standard analytical values of these polymers by the proposed methodology.

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The impact of microcarrier culture optimization on the glycosylation profile of a monoclonal antibody.

Springerplus

December 2013

IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal.

Microcarriers are widely used for the large-scale culture of attachment-dependent cells with increased cell densities and, ultimately, higher product yield. In these processes, the specific culture conditions can affect the quality of the product, which is closely related to its glycosylation pattern. Furthermore, the lack of studies in the area reinforces the need to better understand the effects of microcarrier culture in product glycosylation.

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Adaptation of Listeria monocytogenes in a simulated cheese medium: effects on virulence using the Galleria mellonella infection model.

Lett Appl Microbiol

June 2013

IBB-Institute for Biotechnology and Bioengineering, Centre for Molecular and Structural Biomedicine, Faculdade de Ciências e Tecnologia, Universidade do Algarve, Campus de Gambelas, Faro, Portugal.

Unlabelled: The aim of this study was to evaluate the effect of the acid and salt adaptation in a cheese-based medium on the virulence potential of Listeria monocytogenes strains isolated from cheese and dairy processing environment using the Galleria mellonella model. Four L. monocytogenes strains were exposed to a cheese-based medium in conditions of induction of an acid tolerance response and osmotolerance response (pH 5·5 and 3·5% w/v NaCl) and injected in G.

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Water resources management in southern Europe: clues for a research and innovation based regional hypercluster.

J Environ Manage

April 2013

IBB - Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal.

European countries are facing increasing pressures on their water resources despite stringent regulations and systematic efforts on environmental protection. In this context, research and innovation play a strategic role reinforcing the efficiency of water policies. The present study provides a multilevel assessment of research and innovation practices in the field of water resource management in southern European countries and regions (more specifically; Cyprus, Albania, Poitou-Charentes in France, Andalusia in Spain and the North of Portugal).

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Acoustic detection of cell adhesion to a coated quartz crystal microbalance - implications for studying the biocompatibility of polymers.

Biotechnol J

June 2013

IBB-Institute for Biotechnology and Bioengineering, Center for Molecular and Structural Biomedicine, University of Algarve, Campus de Gambelas, Faro, Portugal.

Biocompatibility of polymers is an important parameter for the successful application of polymers in tissue engineering. In this work, quartz crystal microbalance (QCM) devices were used to follow the adhesion of NIH 3T3 fibroblasts to QCM surfaces modified with fibronectin (FN) and poly-D-lysine (PDL). The variations in sensor resonant frequency (Δf) and motional resistance (ΔR), monitored as the sensor signal, revealed that cell adhesion was favored in the PDL-coated QCMs.

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Mesenchymal stem cells (MSC) could potentially be applied in therapeutic settings due to their multilineage differentiation ability, immunomodulatory properties, as well as their trophic activity. The umbilical cord matrix (UCM) represents a promising source of MSC for biomedical applications. The number of cells isloated per umbilical cord (UC) unit is limited and ex vivo expansion is imperative in order to reach clinically meaningful cell numbers.

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