scholarly journals From Aggregates to Porous Three-Dimensional Scaffolds through a Mechanochemical Approach to Design Photosensitive Chitosan Derivatives

Marine Drugs ◽  
2019 ◽  
Vol 17 (1) ◽  
pp. 48 ◽  
Author(s):  
Kseniia N. Bardakova ◽  
Tatiana A. Akopova ◽  
Alexander V. Kurkov ◽  
Galina P. Goncharuk ◽  
Denis V. Butnaru ◽  
...  
Keyword(s):  
Wavelet Analysis ◽  
Raw Materials ◽  
Three Dimensional ◽  
Chitosan Film ◽  
Biochemical Properties ◽  
In Vivo Studies ◽  
Preparation Methods ◽  
Chitosan Derivatives ◽  
Modified Chitosan

The crustacean processing industry produces large quantities of waste by-products (up to 70%). Such wastes could be used as raw materials for producing chitosan, a polysaccharide with a unique set of biochemical properties. However, the preparation methods and the long-term stability of chitosan-based products limit their application in biomedicine. In this study, different scale structures, such as aggregates, photo-crosslinked films, and 3D scaffolds based on mechanochemically-modified chitosan derivatives, were successfully formed. Dynamic light scattering revealed that aggregation of chitosan derivatives becomes more pronounced with an increase in the number of hydrophobic substituents. Although the results of the mechanical testing revealed that the plasticity of photo-crosslinked films was 5–8% higher than that for the initial chitosan films, their tensile strength remained unchanged. Different types of polymer scaffolds, such as flexible and porous ones, were developed by laser stereolithography. In vivo studies of the formed structures showed no dystrophic and necrobiotic changes, which proves their biocompatibility. Moreover, the wavelet analysis was used to show that the areas of chitosan film degradation were periodic. Comparing the results of the wavelet analysis and X-ray diffraction data, we have concluded that degradation occurs within less ordered amorphous regions in the polymer bulk.

scholarly journals Three-Dimensional Zirconia-Based Scaffolds for Load-Bearing Bone-Regeneration Applications: Prospects and Challenges

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3207
Author(s):  
Kumaresan Sakthiabirami ◽  
Vaiyapuri Soundharrajan ◽  
Jin-Ho Kang ◽  
Yunzhi Peter Yang ◽  
Sang-Won Park
Keyword(s):  
Bone Regeneration ◽  
Biological Activities ◽  
Three Dimensional ◽  
In Vivo Studies ◽  
High Mechanical Strength ◽  
Real World Applications ◽  
3D Fabrication ◽  
Dental Applications

The design of zirconia-based scaffolds using conventional techniques for bone-regeneration applications has been studied extensively. Similar to dental applications, the use of three-dimensional (3D) zirconia-based ceramics for bone tissue engineering (BTE) has recently attracted considerable attention because of their high mechanical strength and biocompatibility. However, techniques to fabricate zirconia-based scaffolds for bone regeneration are in a stage of infancy. Hence, the biological activities of zirconia-based ceramics for bone-regeneration applications have not been fully investigated, in contrast to the well-established calcium phosphate-based ceramics for bone-regeneration applications. This paper outlines recent research developments and challenges concerning numerous three-dimensional (3D) zirconia-based scaffolds and reviews the associated fundamental fabrication techniques, key 3D fabrication developments and practical encounters to identify the optimal 3D fabrication technique for obtaining 3D zirconia-based scaffolds suitable for real-world applications. This review mainly summarized the articles that focused on in vitro and in vivo studies along with the fundamental mechanical characterizations on the 3D zirconia-based scaffolds.

scholarly journals The Challenging Melanoma Landscape: From Early Drug Discovery to Clinical Approval

Cells ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 3088
Author(s):  
Mariana Matias ◽  
Jacinta O. Pinho ◽  
Maria João Penetra ◽  
Gonçalo Campos ◽  
Catarina Pinto Reis ◽  
...  
Keyword(s):  
Therapeutic Potential ◽  
Drug Evaluation ◽  
Three Dimensional ◽  
Experimental Models ◽  
In Vivo Studies ◽  
Murine Models ◽  
In Vivo Experiments ◽  
Novel Therapeutic Strategies

Melanoma is recognized as the most dangerous type of skin cancer, with high mortality and resistance to currently used treatments. To overcome the limitations of the available therapeutic options, the discovery and development of new, more effective, and safer therapies is required. In this review, the different research steps involved in the process of antimelanoma drug evaluation and selection are explored, including information regarding in silico, in vitro, and in vivo experiments, as well as clinical trial phases. Details are given about the most used cell lines and assays to perform both two- and three-dimensional in vitro screening of drug candidates towards melanoma. For in vivo studies, murine models are, undoubtedly, the most widely used for assessing the therapeutic potential of new compounds and to study the underlying mechanisms of action. Here, the main melanoma murine models are described as well as other animal species. A section is dedicated to ongoing clinical studies, demonstrating the wide interest and successful efforts devoted to melanoma therapy, in particular at advanced stages of the disease, and a final section includes some considerations regarding approval for marketing by regulatory agencies. Overall, considerable commitment is being directed to the continuous development of optimized experimental models, important for the understanding of melanoma biology and for the evaluation and validation of novel therapeutic strategies.

scholarly journals Potential anticancer activity of curcumin analogs containing sulfone on human cancer cells

2016 ◽  
Vol 68 (1) ◽  
pp. 125-133 ◽  
Author(s):  
Qiuyan Zhang ◽  
Dongli Li ◽  
Yue Liu ◽  
Hui Wang ◽  
Changyuan Zhang ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Human Cancer ◽  
Three Dimensional ◽  
In Vivo Studies ◽  
Anticancer Activities ◽  
Human Cancer Cells ◽  
Curcumin Analogs ◽  
Phosphorylated Akt ◽  
Transcription 3

Three curcumin analogs(S1-S3) containing sulfone were investigated for their effects on human prostate cancer PC-3, colon cancer HT-29, lung cancer H1299 and pancreatic cancer BxPC-3 cells. The three compounds were approximately 16-to 96-fold more active than curcumin in these cell lines as determined by the MTT assay. The effects of these compounds on cell growth were further studied in prostate cancer PC-3 cells in both two dimensional (2D) and three dimensional (3D) cultures. S1-S3strongly inhibited the growth and induced cell death in PC-3 cells, and the effects of these compounds were associated with suppression of nuclear factor kappa B (NF-?B) transcriptional activity. Moreover, treatment of PC-3 cells with all three compounds caused a decrease in the level of phosphorylated signal transducer and activator of transcription-3 (p-STAT3) (Tyr705),but not p-STAT3(Ser727). Only S1and S2decreased the presence of phosphorylated Akt (p-Akt) in PC-3 cells. These curcumin analogs warrant further in vivo studies for anticancer activities in suitable animal models.

The Effect of Angle and Flow Rate Upon Hemodynamics in Distal Vascular Graft Anastomoses: A Numerical Model Study

1994 ◽  
Vol 116 (3) ◽  
pp. 331-336 ◽  
Author(s):  
Ding-Yu Fei ◽  
James D. Thomas ◽  
Stanley E. Rittgers
Keyword(s):  
Numerical Model ◽  
Stagnation Point ◽  
Arterial Wall ◽  
Artery Bypass ◽  
Three Dimensional ◽  
Separated Flow ◽  
Reynolds Numbers ◽  
In Vivo Studies ◽  
Stagnation Points

Flow in distal end-to-side anastomoses of iliofemoral artery bypass grafts was simulated using a steady flow, three-dimensional numerical model. With the proximal artery occluded, anastomotic angles were varied over 20, 30, 40, 45, 50, 60 and 70 deg while the inlet Reynolds numbers were 100 and 205. Fully developed flow in the graft became somewhat skewed toward the inner wall with increasing angle for both Reynolds numbers. Separated flow regions were seen along the inner arterial wall (toe region) for angles ≥ 60 deg at Re = 100 and for angles ≥ 45 deg at Re = 205 while a stagnation point existed along the outer arterial wall (floor region) for all cases which moved downstream relative to the toe of the anastomosis with decreasing angles. Normalized shear rates (NSR) along the arterial wall varied widely throughout the anastomotic region with negative values seen in the separation zones and upstream of the stagnation points which increased in magnitude with angle. The NSR increased with distance downstream of the stagnation point and with magnitudes which increased with the angle. Compared with observations from chronic in vivo studies, these results appear to support the hypothesis of greater intimal hyperplasia occurring in regions of low fluid shear.

Kinematics of the Midtarsal Joint During Standing Leg Rotation

2002 ◽  
Vol 92 (2) ◽  
pp. 77-81 ◽  
Author(s):  
Christopher Nester ◽  
Peter Bowker ◽  
Peter Bowden
Keyword(s):  
Range Of Motion ◽  
Three Dimensional ◽  
In Vivo Studies ◽  
Kinematic Data ◽  
Joint Characteristics ◽  
Infrared Cameras ◽  
Cadaver Studies ◽  
Midtarsal Joint ◽  
Invasive Techniques

Building on previous work that was cadaver based or involved invasive techniques, this study quantifies the kinematics of an approximation of the midtarsal joint with a noninvasive method. Three-dimensional kinematic data describing the motion of the forefoot and heel during transverse plane rotation of the leg were collected from 25 subjects by means of reflective markers and four infrared cameras. The motion between these segments was assumed to be the best possible clinical approximation of the midtarsal joint. The kinematic characteristics of the midtarsal joint were described in terms of the range and direction of motion in each cardinal body plane, the ratio of the range of motion in each plane, and the orientation of the axis of rotation. The characteristics of the midtarsal joint changed during the range of motion; thus, multiple axes of rotation could be calculated and joint characteristics were varied among subjects. The results of this in vivo method were generally consistent with those of cadaver studies and invasive in vivo studies. (J Am Podiatr Med Assoc 92(2): 77-81, 2002)

scholarly journals Accuracy of aortic annular measurements obtained from three-dimensional echocardiography, CT and MRI: human in vitro and in vivo studies

Heart ◽  
2012 ◽  
Vol 98 (15) ◽  
pp. 1146-1152 ◽  
Author(s):  
Wendy Tsang ◽  
Michael G Bateman ◽  
Lynn Weinert ◽  
Gian Pellegrini ◽  
Victor Mor-Avi ◽  
...  
Keyword(s):  
Three Dimensional ◽  
In Vivo Studies ◽  
Dimensional Echocardiography ◽  
Three Dimensional Echocardiography ◽  
Ct And Mri

scholarly journals Biomimetic insulin-imprinted polymer nanoparticles as a potential oral drug delivery system

2017 ◽  
Vol 67 (2) ◽  
pp. 149-168 ◽  
Author(s):  
Pijush Kumar Paul ◽  
Alongkot Treetong ◽  
Roongnapa Suedee
Keyword(s):  
Molecularly Imprinted Polymers ◽  
Oral Drug Delivery ◽  
Three Dimensional ◽  
In Vivo Studies ◽  
Oral Drug ◽  
Functional Monomers ◽  
Oral Drug Delivery System ◽  
Nanosized Material ◽  
Glucose Reduction

AbstractIn this study, we investigate molecularly imprinted polymers (MIPs), which form a three-dimensional image of the region at and around the active binding sites of pharmaceutically active insulin or are analogous to b cells bound to insulin. This approach was employed to create a welldefined structure within the nanospace cavities that make up functional monomers by cross-linking. The obtained MIPs exhibited a high adsorption capacity for the target insulin, which showed a significantly higher release of insulin in solution at pH 7.4 than at pH 1.2. In vivo studies on diabetic Wistar rats showed that the fast onset within 2 h is similar to subcutaneous injection with a maximum at 4 h, giving an engaged function responsible for the duration of glucose reduction for up to 24 h. These MIPs, prepared as nanosized material, may open a new horizon for oral insulin delivery.

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