1,048 research outputs found

    Advances on Bacterial and Fungal Biofilms for the Production of Added-Value Compounds

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    Simple Summary The production of bio-based materials, including organic acids, antibiotics, enzymes, ethanol, and hydrogen, is generally done by the cultivation of suspended cells rather than using immobilized cells. However, several studies suggest the application of productive biofilms as a reliable alternative for biocatalysis, with many advantages over suspended-growth systems. This review gives an overview of the breakthrough in the application of biofilm platforms for the sustainable production of valuable compounds, with particular insight into the latest advances in the production of recombinant proteins. Productive biofilms are shown to improve production rates and product yields, demonstrating great potential for industrial applications. In recent years, abundant research has been performed on biofilms for the production of compounds with biotechnological and industrial relevance. The use of biofilm platforms has been seen as a compelling approach to producing fine and bulk chemicals such as organic acids, alcohols, and solvents. However, the production of recombinant proteins using this system is still scarce. Biofilm reactors are known to have higher biomass density, operational stability, and potential for long-term operation than suspended cell reactors. In addition, there is an increasing demand to harness industrial and agricultural wastes and biorefinery residues to improve process sustainability and reduce production costs. The synthesis of recombinant proteins and other high-value compounds is mainly achieved using suspended cultures of bacteria, yeasts, and fungi. This review discusses the use of biofilm reactors for the production of recombinant proteins and other added-value compounds using bacteria and fungi

    Impacto de um programa de reabilitação na gestão urinária do doente acometido por acidente vascular cerebral

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    Objective: to assess the effect of a Nursing Rehabilitation program on the urinary incontinence management of women after a CVA. Method: quantitative, quasi-experimental, and longitudinal study conducted in a convalescence unit in the Viana do Castelo district, Portugal, between September 2018 and March 2019. The sample included women (n=30) aged between 45 and 90, experiencing urinary incontinence after a CVA, assigned to two groups: experimental group (n=15) and control group (n=15). The functional rehabilitation program was applied to the experimental group for 4 weeks. The program comprises behavioral changes and an exercise plan to strengthen pelvic floor muscles, and the impact of urinary incontinence was assessed before and after the intervention. Results: a statistically significant correlation was found between the level of functional disability and the impact of urinary incontinence (r=-0.499; p=0.005). Hence, the level of functional disability influences the impact of urinary incontinence on quality of life. The functional rehabilitation program implemented in the experimental group obtained positive results and decreased the frequency (t=6.985, p=0.000) and amount (Z=-2.762, p=0.006) of urine loss. Conclusion: the functional rehabilitation program positively impacted and decreased the frequency and amount of urine loss.info:eu-repo/semantics/publishedVersio

    Water-induced modulation of Helicobacter pylori virulence properties

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    While the influence of water in Helicobacter pylori culturability and membrane integrity has been extensively studied, there are little data concerning the effect of this environment on virulence properties. Therefore, we studied the culturability of water-exposed H. pylori and determined whether there was any relation with the bacterium’s ability to adhere, produce functional components of pathogenicity and induce inflammation and alterations in apoptosis in an experimental model of human gastric epithelial cells. H. pylori partially retained the ability to adhere to epithelial cells even after complete loss of culturability. However, the microorganism is no longer effective in eliciting in vitro host cell inflammation and apoptosis, possibly due to the non-functionality of the cag type IV secretion system. These H. pylori-induced host cell responses, which are lost along with culturability, are known to increase epithelial cell turnover and, consequently, could have a deleterious effect on the initial H. pylori colonisation process. The fact that adhesion is maintained by H. pylori to the detriment of other factors involved in later infection stages appears to point to a modulation of the physiology of the pathogen after water exposure and might provide the microorganism with the necessary means to, at least transiently, colonise the human stomach.FCT (SFRH/BD/24579/2005) (to NMG

    Emerging pharmacotherapy of tinnitus

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    Tinnitus, the perception of sound in the absence of an auditory stimulus, is perceived by about 1 in 10 adults, and for at least 1 in 100, tinnitus severely affects their quality of life. Because tinnitus is frequently associated with irritability, agitation, stress, insomnia, anxiety and depression, the social and economic burdens of tinnitus can be enormous. No curative treatments are available. However, tinnitus symptoms can be alleviated to some extent. The most widespread management therapies consist of auditory stimulation and cognitive behavioral treatment, aiming at improving habituation and coping strategies. Available clinical trials vary in methodological rigor and have been performed for a considerable number of different drugs. None of the investigated drugs have demonstrated providing replicable long-term reduction of tinnitus impact in the majority of patients in excess of placebo effects. Accordingly, there are no FDA or European Medicines Agency approved drugs for the treatment of tinnitus. However, in spite of the lack of evidence, a large variety of different compounds are prescribed off-label. Therefore, more effective pharmacotherapies for this huge and still growing market are desperately needed and even a drug that produces only a small but significant effect would have an enormous therapeutic impact. This review describes current and emerging pharmacotherapies with current difficulties and limitations. In addition, it provides an estimate of the tinnitus market. Finally, it describes recent advances in the tinnitus field which may help overcome obstacles faced in the pharmacological treatment of tinnitus. These include incomplete knowledge of tinnitus pathophysiology, lack of well-established animal models, heterogeneity of different forms of tinnitus, difficulties in tinnitus assessment and outcome measurement and variability in clinical trial methodology. © 2009 Informa UK Ltd.Fil: Langguth, Berthold. Universitat Regensburg; AlemaniaFil: Salvi, Richard. State University of New York; Estados UnidosFil: Elgoyhen, Ana Belen. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentin

    Effects of cadmium and phenanthrene mixtures on aquatic fungi and microbially mediated leaf litter decomposition

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    This version does not correspond to the published one. To access the final version go to: http://www.springerlink.com/content/t8t302617003m078/Urbanization and industrial activities have contributed to widespread contamination by metals and polycyclic aromatic hydrocarbons, but the combined effects of these toxics on aquatic biota and processes are poorly understood. We examined the effects of cadmium (Cd) and phenanthrene on the activity and diversity of fungi associated with decomposing leaf litter in streams. Leaves of Alnus glutinosa were immersed for 10 days in an unpolluted low-order stream in northwest Portugal to allow microbial colonization. Leaves were then exposed in microcosms for 14 days to Cd (0.06–4.5 mg L−1) and phenanthrene (0.2 mg L−1) either alone or in mixture. A total of 19 aquatic hyphomycete species were found sporulating on leaves during the whole study. The dominant species was Articulospora tetracladia, followed by Alatospora pulchella, Clavatospora longibrachiata, and Tetrachaetum elegans. Exposure to Cd and phenanthrene decreased the contribution of A. tetracladia to the total conidial production, whereas it increased that of A. pulchella. Fungal diversity, assessed as denaturing gradient gel electrophoresis fingerprinting or conidial morphology, was decreased by the exposure to Cd and/or phenanthrene. Moreover, increased Cd concentrations decreased leaf decomposition and fungal reproduction but did not inhibit fungal biomass production. Exposure to phenanthrene potentiated the negative effects of Cd on fungal diversity and activity, suggesting that the co-occurrence of these stressors may pose additional risk to aquatic biodiversity and stream ecosystem functioning.The Portuguese Foundation for the Science and Technology supported this work (POCI/MAR/56964/2004) and S. Duarte (SFRH/BPD/47574/2008

    Supramolecular Presentation of Hyaluronan onto Model Surfaces for Studying the Behaviour of Cancer Stem Cells

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    The supramolecular presentation of extracellular matrix components on surfaces provides a platform for the investigation and control of cell behavior. Hyaluronan (HA) is one of the main components of the extracellular environment and has been shown to play an important role in different cancers and their progression. However, current methods of HA immobilization often require its chemical modification. Herein, a peptide-based self-assembled monolayer (SAM) is used as an anchor to immobilize unmodified HA on a bare gold surface, as demonstrated by the quartz crystal microbalance with dissipation monitoring. Peptide-HA surfaces show increased roughness and greater hydrophobicity when compared to poly-D-lysine/HA surfaces, as measured by atomic force microscopy and water contact angle, respectively. Additionally, the peptide SAM can be micro-contact printed and used to restrict the presentation of HA to specific regions, thereby creating HA patterned surfaces to examine cell behavior. When used for cell culture, these surfaces result in altered adhesion and migration of LUC4 head and neck squamous cell carcinoma cells. These biomimetic surfaces can provide insights into the role of HA in cancer and other diseases and be used as a platform for the development of cell sorting devices.C.O’M. thanks The Queen Mary Institute of Bioengineering and the Engineering and Physical Sciences Research Council for financial support through a Ph.D. studentship (Award number 1502316). J.B. gratefully acknowledges the financial support by Fundação para a Ciência e a Tecnologia (FCT), I.P., through individual contract (CEECIND/03202/2017). This work was also funded by national funds (OE), through FCT, I.P., in the scope of the framework contract foreseen in the numbers 4, 5, and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19. The authors also acknowledge the financial support from the EU-funded project “SuprHApolymers” (PCIG14-GA-2013-631871).publishe

    Nano-volume well array chip for large-scale propagation and high-resolution analysis of individual cancer stem cells

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    Copyright: © 2014 Clausell-Tormos J, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Cellular heterogeneity represents an increasingly appreciated aspect for research in life science. To address this issue, we have developed a nano-volume well array chip that allows larger-scale isolation and propagation of single cells. Notably, the chip enables single-cell analysis of freshly isolated primary cells at a high-resolution. With an average height of 130 ± 10 μm and an average diameter of 80 ± 10 μm, each nano-volume well can hold up to 0.4 nL of volume, and is compatible with both adherent as well as 3D suspension cultures. Simultaneous time-lapse imaging of thousands of nano-volume wells allows to monitor cell division, as well as tracking of cell fate, and/or alterations in the microscopic cellular morphology and/or markers expression. To demonstrate its application, we employed the system for propagating and tracking of Cancer Stem Cells (CSCs). CSCs could be monitored over three consecutive days by time-lapse high-resolution imaging at the single-cell level. We could demonstrate that non-CSCs do not dedifferentiate into CSCs, while CSCs were able to give rise to both CSCs and non-CSCs by undergoing symmetric and asymmetric division, respectively. Altogether, we have developed a novel nano-volume well array chip that significantly ameliorates clonal propagation and high-resolution image analysis of rare cells
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