scholarly journals Engineered Collagen Matrices

2020 ◽  
Vol 7 (4) ◽  
pp. 163
Author(s):  
Vaidehi A. Patil ◽  
Kristyn S. Masters
Keyword(s):  
Mechanical Properties ◽  
Tissue Engineering ◽  
De Novo ◽  
Synthetic Polymers ◽  
Chemical Modifications ◽  
Collagen Matrices ◽  
Wide Range ◽  
History Of ◽  
The Creation ◽  
Range Of Values

Collagen is the most abundant protein in mammals, accounting for approximately one-third of the total protein in the human body. Thus, it is a logical choice for the creation of biomimetic environments, and there is a long history of using collagen matrices for various tissue engineering applications. However, from a biomaterial perspective, the use of collagen-only scaffolds is associated with many challenges. Namely, the mechanical properties of collagen matrices can be difficult to tune across a wide range of values, and collagen itself is not highly amenable to direct chemical modification without affecting its architecture or bioactivity. Thus, many approaches have been pursued to design scaffold environments that display critical features of collagen but enable improved tunability of physical and biological characteristics. This paper provides a brief overview of approaches that have been employed to create such engineered collagen matrices. Specifically, these approaches include blending of collagen with other natural or synthetic polymers, chemical modifications of denatured collagen, de novo creation of collagen-mimetic chains, and reductionist methods to incorporate collagen moieties into other materials. These advancements in the creation of tunable, engineered collagen matrices will continue to enable the interrogation of novel and increasingly complex biological questions.

scholarly journals R1352Q CACNA1A Variant in a Patient with Sporadic Hemiplegic Migraine, Ataxia, Seizures and Cerebral Oedema: A Case Report

2021 ◽  
pp. 123-130
Author(s):  
Anker Stubberud ◽  
Emer O’Connor ◽  
Erling Tronvik ◽  
Henry Houlden ◽  
Manjit Matharu
Keyword(s):  
Mental Retardation ◽  
Case Report ◽  
Genetic Testing ◽  
Head Trauma ◽  
Cerebral Oedema ◽  
De Novo ◽  
Minor Head Trauma ◽  
Hemiplegic Migraine ◽  
Wide Range ◽  
History Of

Mutations in the <i>CACNA1A</i> gene show a wide range of neurological phenotypes including hemiplegic migraine, ataxia, mental retardation and epilepsy. In some cases, hemiplegic migraine attacks can be triggered by minor head trauma and culminate in encephalopathy and cerebral oedema. A 37-year-old male without a family history of complex migraine experienced hemiplegic migraine attacks from childhood. The attacks were usually triggered by minor head trauma, and on several occasions complicated with encephalopathy and cerebral oedema. Genetic testing of the proband and unaffected parents revealed a de novo heterozygous nucleotide missense mutation in exon 25 of the <i>CACNA1A</i> gene (c.4055G&#x3e;A, p.R1352Q). The R1352Q <i>CACNA1A</i> variant shares the phenotype with other described <i>CACNA1A</i> mutations and highlights the interesting association of trauma as a precipitant for hemiplegic migraine. Subjects with early-onset sporadic hemiplegic migraine triggered by minor head injury or associated with seizures, ataxia or episodes of encephalopathy should be screened for mutations. These patients should also be advised to avoid activities that may result in head trauma, and anticonvulsants should be considered as prophylactic migraine therapy.

scholarly journals Biomimicry in Bio-Manufacturing: Developments in Melt Electrospinning Writing Technology Towards Hybrid Biomanufacturing

2019 ◽  
Vol 9 (17) ◽  
pp. 3540 ◽  
Author(s):  
Ferdows Afghah ◽  
Caner Dikyol ◽  
Mine Altunbek ◽  
Bahattin Koc
Keyword(s):  
Mechanical Properties ◽  
Tissue Engineering ◽  
Cell Attachment ◽  
Three Dimensional ◽  
Future Perspective ◽  
Melt Electrospinning ◽  
Wide Range ◽  
Challenges And Opportunities ◽  
Potential Applications ◽  
Homogeneous Cell

Melt electrospinning writing has been emerged as a promising technique in the field of tissue engineering, with the capability of fabricating controllable and highly ordered complex three-dimensional geometries from a wide range of polymers. This three-dimensional (3D) printing method can be used to fabricate scaffolds biomimicking extracellular matrix of replaced tissue with the required mechanical properties. However, controlled and homogeneous cell attachment on melt electrospun fibers is a challenge. The combination of melt electrospinning writing with other tissue engineering approaches, called hybrid biomanufacturing, has introduced new perspectives and increased its potential applications in tissue engineering. In this review, principles and key parameters, challenges, and opportunities of melt electrospinning writing, and particularly, recent approaches and materials in this field are introduced. Subsequently, hybrid biomanufacturing strategies are presented for improved biological and mechanical properties of the manufactured porous structures. An overview of the possible hybrid setups and applications, future perspective of hybrid processes, guidelines, and opportunities in different areas of tissue/organ engineering are also highlighted.

scholarly journals Synthesis, Characterization and Mechanical Properties of Nanocomposites Based on Novel Carbon Nanowires and Polystyrene

2020 ◽  
Vol 10 (17) ◽  
pp. 5737
Author(s):  
Vasilis Kostas ◽  
Maria Baikousi ◽  
Nektaria-Marianthi Barkoula ◽  
Aris Giannakas ◽  
Antonios Kouloumpis ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Analytical Techniques ◽  
Polymer Nanocomposite ◽  
Precipitation Method ◽  
Templating Method ◽  
Polymer Properties ◽  
Wide Range ◽  
First Time ◽  
Range Of Values ◽  
Carbon Nanowires

Carbon into polymer nanocomposite is so far a common additive for the enhancement of the polymer properties. The properties of the polymer, such as thermal, and especially its mechanical properties, are improved by the homogeneously dispersed carbon nanoparticles on the polymer matrix. In this study, carbon wires in nano dimensions are, for the very first time, synthesized via the hard templating method from the silicate matrix MCM-41, and used as nano additives of polystyrene. The carbon nanowires were chemically oxidized, and further modified by attaching octadecylamine molecules, for the development of organic functionalities onto carbon nanowires surface. The nanocomposite materials of polystyrene with the modified carbon nanowires were prepared by a solution-precipitation method at three nano additive to polymer loadings (1, 3 and 5 wt%). The as-derived nanocomposites were studied with a combination of characterization and analytical techniques. The results showed that the thermal and mechanical properties of the polystyrene nanocomposites gradually improved while increasing nano-additive loading until 3 wt%. More specifically, the 3 wt% loading sample showed the best mechanical properties, while the 5 wt% sample was difficult to achieve satisfactory dispersion of carbon nanowires and consequently has a wide range of values.

scholarly journals Mesenchymal Stromal/Stem Cells in Regenerative Medicine and Tissue Engineering

2018 ◽  
Vol 2018 ◽  
pp. 1-16 ◽  
Author(s):  
Ross E. B. Fitzsimmons ◽  
Matthew S. Mazurek ◽  
Agnes Soos ◽  
Craig A. Simmons
Keyword(s):  
Tissue Engineering ◽  
Stem Cells ◽  
Regenerative Medicine ◽  
Ex Vivo ◽  
Therapeutic Effects ◽  
Wide Range ◽  
History Of ◽  
Initial Discovery ◽  
Stromal Stem Cells

As a result of over five decades of investigation, mesenchymal stromal/stem cells (MSCs) have emerged as a versatile and frequently utilized cell source in the fields of regenerative medicine and tissue engineering. In this review, we summarize the history of MSC research from the initial discovery of their multipotency to the more recent recognition of their perivascular identity in vivo and their extraordinary capacity for immunomodulation and angiogenic signaling. As well, we discuss long-standing questions regarding their developmental origins and their capacity for differentiation toward a range of cell lineages. We also highlight important considerations and potential risks involved with their isolation, ex vivo expansion, and clinical use. Overall, this review aims to serve as an overview of the breadth of research that has demonstrated the utility of MSCs in a wide range of clinical contexts and continues to unravel the mechanisms by which these cells exert their therapeutic effects.

scholarly journals Tissue Engineering for the Insertions of Tendons and Ligaments: An Overview of Electrospun Biomaterials and Structures

2021 ◽  
Vol 9 ◽  
Author(s):  
Alberto Sensini ◽  
Gabriele Massafra ◽  
Carlo Gotti ◽  
Andrea Zucchelli ◽  
Luca Cristofolini
Keyword(s):  
Mechanical Properties ◽  
Tissue Engineering ◽  
Myotendinous Junction ◽  
Stress Concentrations ◽  
Comprehensive Overview ◽  
Electrospinning Technique ◽  
Junction Site ◽  
Wide Range ◽  
Myotendinous Junctions

The musculoskeletal system is composed by hard and soft tissue. These tissues are characterized by a wide range of mechanical properties that cause a progressive transition from one to the other. These material gradients are mandatory to reduce stress concentrations at the junction site. Nature has answered to this topic developing optimized interfaces, which enable a physiological transmission of load in a wide area over the junction. The interfaces connecting tendons and ligaments to bones are called entheses, while the ones between tendons and muscles are named myotendinous junctions. Several injuries can affect muscles, bones, tendons, or ligaments, and they often occur at the junction sites. For this reason, the main aim of the innovative field of the interfacial tissue engineering is to produce scaffolds with biomaterial gradients and mechanical properties to guide the cell growth and differentiation. Among the several strategies explored to mimic these tissues, the electrospinning technique is one of the most promising, allowing to generate polymeric nanofibers similar to the musculoskeletal extracellular matrix. Thanks to its extreme versatility, electrospinning has allowed the production of sophisticated scaffolds suitable for the regeneration of both the entheses and the myotendinous junctions. The aim of this review is to analyze the most relevant studies that applied electrospinning to produce scaffolds for the regeneration of the enthesis and the myotendinous junction, giving a comprehensive overview on the progress made in the field, in particular focusing on the electrospinning strategies to produce these scaffolds and their mechanical, in vitro, and in vivo outcomes.

scholarly journals Establishing the diagnosis neurofibromatosis type 1: A rare case

2019 ◽  
Author(s):  
Dyatiara Devy ◽  
D. Damayanti
Keyword(s):  
Neurofibromatosis Type 1 ◽  
De Novo ◽  
Malignant Tumors ◽  
Neurofibromatosis Type ◽  
The Body ◽  
Multisystem Disorder ◽  
Wide Range ◽  
Multidisciplinary Clinic ◽  
History Of

Neurofibromatosis type 1 (NF1) or Von Recklinghausen's disease is a dominantly inherited genetic, multisystem disorder. Individuals with neurofibromatosis type 1 are prone to develop benign and malignant tumors of the CNS and peripheral nervous system, in addition to malignant diseases affecting other parts of the body. About 50% of individuals with neurofibromatosis type 1 have no family history of the disease and the disease is due to de novo (spontaneous) mutations. Early diagnosis is challenging because of its extremely variable characteristics. Some individuals may be mildly affected showing minimal signs, whereas others are severely afflicted. Individuals with NF-1 are best cared for within a multidisciplinary clinic, which has access to a wide range of subspecialists. The dermatologist has a role not only in the diagnosis of NF1 and differentiating it from other similar disorders, but also in the recognition of rare associated skin manifestations.

scholarly journals Chromosome 20p Partial De Novo Duplication Identified in a Female Paediatric Patient with Characteristic Facial Dysmorphism and Behavioural Anomalies

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Shahzaib Khattak ◽  
Meryam Jan ◽  
Sara Warsi ◽  
Sohail Khattak
Keyword(s):  
Scientific Literature ◽  
De Novo ◽  
Heart Defects ◽  
Self Regulation ◽  
Alagille Syndrome ◽  
Copy Number Variations ◽  
Facial Dysmorphism ◽  
Limited Data ◽  
Wide Range ◽  
History Of

Copy number variations (CNVs) involving the JAG1 gene are rare and infrequently reported in the scientific literature. Recently, a generally healthy young patient presenting with a history of behavioural concerns was referred to us. Herein, we discuss the patient, a 7-year-old female possessing a 0.797 Mb microduplication within the short arm of chromosome 20 at band 12.2. The patient generates considerable curiosity due to the rarity of her case, which includes a de novo partial duplication involving the JAG1 gene. The patient exhibits a wide range of symptoms including facial dysmorphism (dolichocephaly, round face, tented philtrum, anteverted nares, and micrognathia), clinodactyly, and an inborn congenital heart defect. She presented with behavioural concerns including ADHD-I, SPD, motor clumsiness, and poor self-regulation. Deletions in JAG1 are often linked to Alagille Syndrome; however, complete duplications have not been specifically identified as disease-causing. JAG1 mutations are reported alongside various clinical features including facial dysmorphology, heart defects, vertebral abnormalities, and ocular dysmorphic features (strabismus, epicanthal folds, and slanted palpebral fissures). This particular microduplication is rare, and thus, limited data exist regarding its significance. To our knowledge, most reported duplications are larger than 0.797 Mb. This may define a critical region causing phenotypical changes in some patient cases.

scholarly journals Seven Billion Microcosms: Evolution within Human Microbiomes

mSystems ◽  
2018 ◽  
Vol 3 (2) ◽  
Author(s):  
Tami D. Lieberman
Keyword(s):  
De Novo ◽  
Human Microbiome ◽  
Survival Strategies ◽  
System Level ◽  
Individual Species ◽  
Knowledge Gap ◽  
Bacterial Strains ◽  
Wide Range ◽  
Evolutionary Inference ◽  
History Of

ABSTRACT Rational microbiome-based therapies may one day treat a wide range of diseases and promote wellness. Yet, we are still limited in our abilities to employ such therapies and to predict which bacterial strains have the potential to stably colonize a person. The Lieberman laboratory is working to close this knowledge gap and to develop an understanding of how individual species and strains behave in the human microbiome, including with regard to their niche ranges, survival strategies, and the degree to which they adapt to individual people. We employ system-level approaches, with a particular emphasis on using de novo mutations and evolutionary inference to reconstruct the history of bacterial lineages within individuals.

A Brief Review of the Modelling of the Time Dependent Mechanical Properties of Tissue Engineering Scaffolds

2010 ◽  
Vol 6 ◽  
pp. 19-33 ◽  
Author(s):  
N.K. Bawolin ◽  
W.J. Zhang ◽  
Xiong Biao Chen
Keyword(s):  
Mechanical Properties ◽  
Tissue Engineering ◽  
Treatment Process ◽  
Effective Properties ◽  
Critical Role ◽  
Time Dependent ◽  
Tissue Engineering Scaffolds ◽  
Wide Range ◽  
Scaffold Degradation

The functionality of tissue scaffolds in vivo plays a critical role in the treatment process. Due to the time dependent nature of the mechanical properties of the constituent phases of the scaffold, a wide range of mechanical property histories may be observed during the treatment process, possibly influencing outcomes. The critical nature of the mechanical properties in load bearing applications indicates a need for the simultaneous modelling of both scaffold degradation and tissue regeneration with time, and the resulting effective properties of the tissue engineering construct. To this end, a review of the literature is conducted to identify the various existing approaches to modelling scaffold degradation, tissue behavior, and the dependency of the two processes on one another.

scholarly journals Two-Photon Polymerized Poly(2-Ethyl-2-Oxazoline) Hydrogel 3D Microstructures with Tunable Mechanical Properties for Tissue Engineering

Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 5066
Author(s):  
Steffen Czich ◽  
Thomas Wloka ◽  
Holger Rothe ◽  
Jürgen Rost ◽  
Felix Penzold ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tissue Engineering ◽  
Computer Aided Design ◽  
Evaluation Method ◽  
Structural Integrity ◽  
Viscoelastic Behavior ◽  
Main Task ◽  
Two Photon ◽  
Wide Range ◽  
Tunable Mechanical Properties

The main task of tissue engineering (TE) is to reproduce, replicate, and mimic all kinds of tissues in the human body. Nowadays, it has been proven useful in TE to mimic the natural extracellular matrix (ECM) by an artificial ECM (scaffold) based on synthetic or natural biomaterials to regenerate the physiological tissue/organ architecture and function. Hydrogels have gained interest in the TE community because of their ability to absorb water similar to physiological tissues, thus mechanically simulating the ECM. In this work, we present a novel hydrogel platform based on poly(2-ethyl-2-oxazoline)s, which can be processed to 3D microstructures via two-photon polymerization (2PP) with tunable mechanical properties using monomers and crosslinker with different degrees of polymerization (DP) for future applications in TE. The ideal parameters (laser power and writing speed) for optimal polymerization via 2PP were obtained using a specially developed evaluation method in which the obtained structures were binarized and compared to the computer-aided design (CAD) model. This evaluation was performed for each composition. We found that it was possible to tune the mechanical properties not only by application of different laser parameters but also by mixing poly(2-ethyl-2-oxazoline)s with different chain lengths and variation of the crosslink density. In addition, the swelling behavior of different fabricated hydrogels were investigated. To gain more insight into the viscoelastic behavior of different fabricated materials, stress relaxation tests via nanoindentation experiments were performed. These new hydrogels can be processed to 3D microstructures with high structural integrity using optimal laser parameter settings, opening a wide range of application properties in TE for this material platform.

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