Biopolymers advances in Medical Sciences: An Editorial Review

Biomaterials a term is used to describe the materials which are typically derived from any biological source. In generally it is said that these are the materials which are used within the human body to perform certain functions such as therapies1. The applications of polymers in the field of medicine have already gave birth to polymer science as a field. As we can see today, almost every polymer have been reported for use in any kind of clinical intervention, they are inseparable part of us now. Polymers are key players in clinical medicine as they are fundamental components of permanent prosthetic devices such as diameter vascular grafts, artificial lenses, catheters, hip implants etc., and the research is continued to perfect the performance and stability of polymers in vitro and in vivo2. However, the use of polymers in surgery is somewhat confined to connective tissue replacements. Interestingly, polymers have opened new horizons for drug delivery and gene therapy treatments such as nucleic-acid based drugs and protein-based drugs which cannot be taken up as typical pills, are providing impulsion for contemporary implantable polymers. The applications of polymers in tissue engineering are also gaining spotlight as these materials helps in the regeneration of 3D- (three-dimensional) organ and tissue structures.

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New horizons for in vitro spermatogenesis? An update on novel three-dimensional culture systems as tools for meiotic and post-meiotic differentiation of testicular germ cells

MHR Basic science of reproductive medicine ◽

10.1093/molehr/gap052 ◽

2009 ◽

Vol 15 (9) ◽

pp. 521-529 ◽

Cited By ~ 113

Author(s):

J.-B. Stukenborg ◽

S. Schlatt ◽

M. Simoni ◽

C.-H. Yeung ◽

M. A. Elhija ◽

...

Keyword(s):

Germ Cells ◽

Three Dimensional ◽

New Horizons ◽

Culture Systems ◽

In Vitro Spermatogenesis ◽

Three Dimensional Culture

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Three-Dimensional Modeling and Simulation of Muscle Tissue Puncture Process

10.21203/rs.3.rs-532040/v1 ◽

2021 ◽

Author(s):

zongkai lv ◽

qinghua song ◽

fan gao ◽

zhanqiang liu ◽

yi wan ◽

...

Keyword(s):

Success Rate ◽

Muscle Tissue ◽

Clinical Medicine ◽

Three Dimensional ◽

Virtual Surgery ◽

Three Dimensional Modeling ◽

Simulation Results ◽

High Degree ◽

Puncture Model

Abstract Needle biopsy is an important part of modern clinical medicine. The puncture accuracy and sampling success rate of puncture surgery can be effectively improved through virtual surgery. Because fewer puncture existing three-dimensional(3D) model, it is impossible to guide the operation under complicated working conditions, which limits the development of virtual surgery. In this paper, 3D simulation of muscle tissue puncture process is studied. Firstly, the parameters of muscle tissue are measured. Considering the fitting accuracy and calculation speed, the M-R model is selected. Subsequently, an accurate 3D dynamic puncture model is established. The failure criterion is used to define the breaking characteristics of the muscle, and the bilinear cohesion model defines the breaking process. Experiments with different puncture speeds are carried out through the built in vitro puncture platform. The experimental results are compared with the simulation results. The accuracy of the model is verified by the high degree of agreement between the two curves. Finally, the model under different parameters is studied. Analyze the simulation results of different puncture depths and puncture speeds. The 3D puncture model can provide a more accurate model support for virtual surgery and help improve the success rate of puncture surgery.

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Fabrication of Subretinal 3D Microelectrodes with Hexagonal Arrangement

Micromachines ◽

10.3390/mi11050467 ◽

2020 ◽

Vol 11 (5) ◽

pp. 467 ◽

Cited By ~ 1

Author(s):

Hee Won Seo ◽

Namju Kim ◽

Sohee Kim

Keyword(s):

Integrated Circuit ◽

Microelectrode Array ◽

3D Structure ◽

Three Dimensional ◽

Active Electrode ◽

Prosthetic Devices ◽

In Vivo Experiments ◽

Hexagonal Arrangement

This study presents the fabrication of three-dimensional (3D) microelectrodes for subretinal stimulation, to accommodate adjacent return electrodes surrounding a stimulating electrode. For retinal prosthetic devices, the arrangement of return electrodes, the electrode size and spacing should be considered together, to reduce the undesired dissipation of electric currents. Here, we applied the hexagonal arrangement to the microelectrode array for the localized activation of retinal cells and better visual acuity. To provide stimuli more efficiently to non-spiking neurons, a 3D structure was created through a customized pressing process, utilizing the elastic property of the materials used in the fabrication processes. The diameter and pitch of the Pt-coated electrodes were 150 μm and 350 μm, respectively, and the height of the protruded electrodes was around 20 μm. The array consisted of 98 hexagonally arranged electrodes, supported by a flexible and transparent polydimethylsiloxane (PDMS) base, with a thickness of 140 μm. Also, the array was coated with 2 μm-thick parylene-C, except the active electrode sites, for more focused stimulation. Finally, the electrochemical properties of the fabricated microelectrodes were characterized, resulting in the mean impedance of 384.87 kΩ at 1 kHz and the charge storage capacity (CSC) of 2.83 mC·cm−2. The fabricated microelectrodes are to be combined with an integrated circuit (IC) for additional in vitro and in vivo experiments.

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Renewable chitin from marine sponge as a thermostable biological template for hydrothermal synthesis of hematite nanospheres using principles of extreme biomimetics

Bioinspired Materials ◽

10.1515/bima-2015-0001 ◽

2015 ◽

Vol 1 (1) ◽

Cited By ~ 9

Author(s):

Marcin Wysokowski ◽

Iaroslav Petrenko ◽

Mykhailo Motylenko ◽

Enrico Langer ◽

Vasilii V. Bazhenov ◽

...

Keyword(s):

Hydrothermal Synthesis ◽

Three Dimensional ◽

Basic Element ◽

Marine Sponges ◽

Regeneration Ability ◽

Hydrothermal Conditions ◽

Biological Source ◽

Aplysina Aerophoba ◽

Light Fluorescence

AbstractChitin originating from marine sponges possesses a unique nanofibrillar network structure that is the basic element of the microtubular scaffold-like skeleton of these organisms. Sponge chitin represents an intriguing example of thermostability, as it is stable up to 400 °C. It also constitutes a renewable biological source due to the high regeneration ability of Aplysina sponges under marine farming conditions. These properties can be exploited for the facile and environmentally friendly creation of novel, biocompatible organic-inorganic hybrid materials with a range of uses. Here, chitin-based scaffolds isolated from the skeleton of marine demosponge Aplysina aerophoba were used as a template for the in vitro formation of iron oxide from a saturated iron(III) chloride solution, under hydrothermal conditions (pH~1.5, 90 °C). The resultant chitin-Fe2O3 three dimensional composites, prepared for the first time via hydrothermal synthesis route, were thoroughly characterized using light, fluorescence and scanning electron microscopy; as well as with analytical methods like Raman spectroscopy, electron diffraction and HR-TEM. The results show that this versatile method allows for efficient chitin mineralization with respect to hematite. Additionally, we demonstrate that chitin nanofibers template the nucleation of uniform Fe2O3 nanocrystals.

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Ultrastructural Investigations of the Contractile Filaments of Amoebae

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100050950 ◽

1974 ◽

Vol 32 ◽

pp. 188-189

Author(s):

P.L. Moore

Keyword(s):

Cytoplasmic Streaming ◽

Three Dimensional ◽

Freeze Fracture ◽

Amoeboid Movement ◽

Different Types ◽

Chemical Conditions ◽

Complete Interpretation

Previous freeze fracture results on the intact giant, amoeba Chaos carolinensis indicated the presence of a fibrillar arrangement of filaments within the cytoplasm. A complete interpretation of the three dimensional ultrastructure of these structures, and their possible role in amoeboid movement was not possible, since comparable results could not be obtained with conventional fixation of intact amoebae. Progress in interpreting the freeze fracture images of amoebae required a more thorough understanding of the different types of filaments present in amoebae, and of the ways in which they could be organized while remaining functional.The recent development of a calcium sensitive, demembranated, amoeboid model of Chaos carolinensis has made it possible to achieve a better understanding of such functional arrangements of amoeboid filaments. In these models the motility of demembranated cytoplasm can be controlled in vitro, and the chemical conditions necessary for contractility, and cytoplasmic streaming can be investigated. It is clear from these studies that “fibrils” exist in amoeboid models, and that they are capable of contracting along their length under conditions similar to those which cause contraction in vertebrate muscles.

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Correlated Studies of Cellular Interactions Using TEM, Freeze Etching, and SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010005161x ◽

1974 ◽

Vol 32 ◽

pp. 320-321

Author(s):

J. P. Revel

Keyword(s):

Developmental Stages ◽

Three Dimensional ◽

Cell Movement ◽

Cellular Interactions ◽

Serial Sections ◽

Cell Sheets ◽

Freeze Etching ◽

Early Developmental

Movement of individual cells or of cell sheets and complex patterns of folding play a prominent role in the early developmental stages of the embryo. Our understanding of these processes is based on three- dimensional reconstructions laboriously prepared from serial sections, and from autoradiographic and other studies. Many concepts have also evolved from extrapolation of investigations of cell movement carried out in vitro. The scanning electron microscope now allows us to examine some of these events in situ. It is possible to prepare dissections of embryos and even of tissues of adult animals which reveal existing relationships between various structures more readily than used to be possible vithout an SEM.

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In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083035 ◽

1978 ◽

Vol 36 (2) ◽

pp. 434-435

Author(s):

D. Reis ◽

B. Vian ◽

J. C. Roland

Keyword(s):

Cell Wall ◽

Self Assembly ◽

Plant Cell Wall ◽

Higher Plants ◽

Three Dimensional ◽

Cytochemical Study ◽

Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

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