Search results for "Bioengineering"

Anhydrobiosis in yeast: cell wall mannoproteins are important for yeastSaccharomyces cerevisiaeresistance to dehydration

2016

The state of anhydrobiosis is linked with the reversible delay of metabolism as a result of strong dehydration of cells, and is widely distributed in nature. A number of factors responsible for the maintenance of organisms' viability in these conditions have been revealed. This study was directed to understanding how changes in cell wall structure may influence the resistance of yeasts to dehydration-rehydration. Mutants lacking various cell wall mannoproteins were tested to address this issue. It was revealed that mutants lacking proteins belonging to two structurally and functionally unrelated groups (proteins non-covalently attached to the cell wall, and Pir proteins) possessed significa…

Myeloid cells as orchestrators of the tumor microenvironment: novel targets for nanoparticular cancer therapy.

2016

Macrophages, myeloid-derived suppressor cells and tolerogenic dendritic cells are central players of a heterogeneous myeloid cell population, with the ability to suppress innate and adaptive immune responses and thus to promote tumor growth. Their influx and local proliferation are mainly induced by the cancers themselves, and their numbers in the tumor microenvironment and the peripheral blood correlate with decreased survival. Therapeutic targeting these innate immune cells, either aiming at their elimination or polarization toward tumor suppressive cells is an attractive novel approach to control tumor progression and block metastasis. We review the current understanding of cancer immun…

Protein-Free Hapten-Carbon Nanotube Constructs Induce the Secondary Immune Response

2017

Carbon nanotubes are novel technological tools with multiple applications. The interaction between such nanoparticles and living organisms is nowadays a matter of keen research by academic and private institutions. In this study, carbon nanotube constructs were investigated as delivery vehicles for immunostimulation and induction of the secondary immune response to a small organic molecule, namely, a hapten. Two types of nanoconstructs were prepared: on one hand, carbon nanotubes carrying a protein bioconjugate of a hapten covalently linked to the carbon surface, and on the other hand, covalent carbon nanotube constructs of the same model chemical compound without the carrier protein. Nanot…

2020

Human movements are characterized by highly non-linear and multi-dimensional interactions within the motor system. Recently, an increasing emphasis on machine-learning applications has led to a significant contribution to the field of gait analysis, e.g., in increasing the classification performance. In order to ensure the generalizability of the machine-learning models, different data preprocessing steps are usually carried out to process the measured raw data before the classifications. In the past, various methods have been used for each of these preprocessing steps. However, there are hardly any standard procedures or rather systematic comparisons of these different methods and their im…

Long-Term in vivo Evaluation of Orthotypical and Heterotypical Bioengineered Human Corneas.

2020

Purpose: Human cornea substitutes generated by tissue engineering currently require limbal stem cells for the generation of orthotypical epithelial cell cultures. We recently reported that bioengineered corneas can be fabricated in vitro from a heterotypical source obtained from Wharton’s jelly in the human umbilical cord (HWJSC). Methods: Here, we generated a partial thickness cornea model based on plastic compression nanostructured fibrin-agarose biomaterials with cornea epithelial cells on top, as an orthotypical model (HOC), or with HWJSC, as a heterotypical model (HHC), and determined their potential in vivo usefulness by implantation in an animal model. Results: No major side effects …

Regeneration of periodontal bone defects with dental pulp stem cells grafting: systematic rewiew

2019

Background The main objective is to evaluate the way to graft the dental pulp stem cells (DPSC) in periodontal defects that best regenerate periodontal tissues. Numerous procedures have been done to promote periodontal regeneration. Bone grafts show good gains clinically and radiographically but histologically seem to have minimal osteoinductive capacity. Another option that exceeds conventional surgery in reducing probing depth and increasing insertion is guided tissue regeneration and tissue engineering that could be an alternative approach to help in the regeneration of living functional bone and peri-dental structures. Material and Methods A search was carried out in Cochrane, PubMed-ME…

Effectiveness of flossing loops in the control of the gingival health

2017

Reference Number: 53858 Background: One of the key factor in the good condition of periodontal tissues is their daily hygiene. Oral hygiene techniques such brushing and a good interdental hygiene by correct flossing are very important. The aim of this study is to compare the use of dental floss in a loop vs traditional floss in the control of Loe-Silness Gingival In- dex (IG), Turesky ́s Plaque Index (IPT), Gingival Bleeding Index (IS) and the values of interleukin 6 (IL-6) and interleukin 8 (IL-8). Material and Methods: A comparative study of 40 patients in which each patient was his own control, using during 45 days each one of the devices (new loop floss and conventional floss) of interd…

Photocrosslinked Dextran-Based Hydrogels as Carrier System for the Cells and Cytokines Induce Bone Regeneration in Critical Size Defects in Mice

2018

Modified biomaterials have for years been the focus of research into establishing new bone substitutes. In our preceding in vitro study employing different cell cultures, we developed chemically and mechanically characterized hydrogels based on photocrosslinkable dextran derivatives and demonstrated their cytocompatibility and their beneficial effects on the proliferation of osteoblasts and endothelial cells. In the present in vivo study, we investigate photocrosslinked dextran-based hydrogels in critical size defects in mice to evaluate their potential as carrier systems for cells or for a specific angiogenesis enhancing cytokine to induce bone formation. We could demonstrate that, with op…

Basement Membrane Mimics of Biofunctionalized Nanofibers for a Bipolar-Cultured Human Primary Alveolar-Capillary Barrier Model

2017

In vitro reconstruction of an alveolar barrier for modeling normal lung functions and pathological events serve as reproducible, high-throughput pharmaceutical platforms for drug discovery, diagnosis, and regenerative medicine. Despite much effort, the reconstruction of organ-level alveolar barrier functions has failed due to the lack of structural similarity to the natural basement membrane, functionalization with specific ligands for alveolar cell function, the use of primary cells and biodegradability. Here we report a bipolar cultured alveolar-capillary barrier model of human primary cells supported by a basement membrane mimics of fully synthetic bifunctional nanofibers. One-step elect…

Wet Chemistry and Peptide Immobilization on Polytetrafluoroethylene for Improved Cell-adhesion

2016

Endowing materials surface with cell-adhesive properties is a common strategy in biomaterial research and tissue engineering. This is particularly interesting for already approved polymers that have a long standing use in medicine because these materials are well characterized and legal issues associated with the introduction of newly synthesized polymers may be avoided. Polytetrafluoroethylene (PTFE) is one of the most frequently employed materials for the manufacturing of vascular grafts but the polymer lacks cell adhesion promoting features. Endothelialization, i.e., complete coverage of the grafts inner surface with a confluent layer of endothelial cells is regarded key to optimal perfo…