Non-Contact Experimental Assessment of Spinal Facet Joint Cartilage Dehydration

2012 ◽  
Author(s):  
Loren Kim ◽  
Peter Simon ◽  
Gunnar Andersson ◽  
Howard S. An ◽  
Nozomu Inoue ◽  
...  
Keyword(s):  
Facet Joint ◽  
Morphological Changes ◽  
High Surface ◽  
Experimental Studies ◽  
Volume Ratio ◽  
Ambient Air ◽  
Thickness Measurement ◽  
Joint Cartilage ◽  
Exponential Trend

Dehydration may cause undesirable morphological changes in small hydrated tissue with high surface-to-volume ratio during in vitro experimentation that can result in erroneous data. The lumbar facet joint cartilage, an example of such tissue, is highly susceptible to dehydration due its high content of water (60% to 80% by volume) when exposed to ambient air [1]. Recent studies involving thickness measurement of articular human and bovine cartilage from the tibial plateau reported distinct decreases in thickness due to dehydration and the importance of maintaining its hydration during biomechanical experimental studies [1–3]. Knee joint and facet joint cartilage are characterized as hyaline cartilage surrounded by synovial fluid and encased in a joint capsule. The fact that both are synovial joints suggests that facet joint cartilage may show similar dehydration rates; however, due to its smaller size and different surface-to-volume, the dehydration rate is expected to be higher for facet joint cartilage. To the best of the authors’ knowledge, the rate of facet joint cartilage dehydration has not been quantified before. It is hypothesized that the facet joint cartilage thickness will decrease in an inverse exponential trend and significant changes will be seen as dehydration time intervals time increases. The objectives of this study were: 1) quantify the dimensional stability of the cartilage samples under a sequential dehydration protocol, and 2) to evaluate the cartilage shrinkage rate.

scholarly journals The Neuroinflammatory Role of Pericytes in Epilepsy

Biomedicines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 759
Author(s):  
Gaku Yamanaka ◽  
Fuyuko Takata ◽  
Yasufumi Kataoka ◽  
Kanako Kanou ◽  
Shinichiro Morichi ◽  
...  
Keyword(s):  
Proinflammatory Cytokines ◽  
Current Knowledge ◽  
Morphological Changes ◽  
Cell Damage ◽  
Neurovascular Unit ◽  
Experimental Studies ◽  
Intractable Epilepsy ◽  
In Vivo Studies

Pericytes are a component of the blood–brain barrier (BBB) neurovascular unit, in which they play a crucial role in BBB integrity and are also implicated in neuroinflammation. The association between pericytes, BBB dysfunction, and the pathophysiology of epilepsy has been investigated, and links between epilepsy and pericytes have been identified. Here, we review current knowledge about the role of pericytes in epilepsy. Clinical evidence has shown an accumulation of pericytes with altered morphology in the cerebral vascular territories of patients with intractable epilepsy. In vitro, proinflammatory cytokines, including IL-1β, TNFα, and IL-6, cause morphological changes in human-derived pericytes, where IL-6 leads to cell damage. Experimental studies using epileptic animal models have shown that cerebrovascular pericytes undergo redistribution and remodeling, potentially contributing to BBB permeability. These series of pericyte-related modifications are promoted by proinflammatory cytokines, of which the most pronounced alterations are caused by IL-1β, a cytokine involved in the pathogenesis of epilepsy. Furthermore, the pericyte-glial scarring process in leaky capillaries was detected in the hippocampus during seizure progression. In addition, pericytes respond more sensitively to proinflammatory cytokines than microglia and can also activate microglia. Thus, pericytes may function as sensors of the inflammatory response. Finally, both in vitro and in vivo studies have highlighted the potential of pericytes as a therapeutic target for seizure disorders.

Preparation of Electrospun PLA Nanofiber Scaffold and the Evaluation In Vitro

2005 ◽  
Vol 288-289 ◽  
pp. 139-142 ◽  
Author(s):  
Xian Tao Wen ◽  
Hong Song Fan ◽  
Yan Fei Tan ◽  
H.D. Cao ◽  
H. Li ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Soft Tissue ◽  
High Surface ◽  
Volume Ratio ◽  
Electrospinning Process ◽  
High Porosity ◽  
Electrospun Scaffold ◽  
Nanofiber Scaffold ◽  
Soft Tissue Engineering

A electrospinning process to prepare soft tissue engineering scaffold was introduced in this study. This kind of scaffold was composed with ultrathin fiber and characterized with high porosity, well-interconnected pores and high surface-to-volume ratio. Biodegradable polylaticacid (PLA) was used to spin the scaffold and the scaffold was evaluated in vitro by analysis the microscopic structure, porosity, mechanical property, especially cytocompatibility. The results indicated that the electrospun PLA scaffold showed good cytocompatibility and the tensile property of electrospun scaffold was similar to human’s soft tissue. It could be expected that the electrospun scaffold would be potential in soft tissue engineering or soft tissue repair.

scholarly journals A Mucoadhesive Electrospun Nanofibrous Matrix for Rapid Oramucosal Drug Delivery

2013 ◽  
Vol 2013 ◽  
pp. 1-19 ◽  
Author(s):  
Clare Dott ◽  
Charu Tyagi ◽  
Lomas K. Tomar ◽  
Yahya E. Choonara ◽  
Pradeep Kumar ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Adhesion Force ◽  
High Surface ◽  
Experimental Studies ◽  
Volume Ratio ◽  
Work Of Adhesion ◽  
Computer Assisted ◽  
Glycerol Concentration ◽  
Disintegration Time ◽  
Fill Volume

A nanofibrous matrix system (NFMS), consisting of a drug-loaded nanofiber layer, was electrospun directly onto a polymeric backing film, the latter of which was formulated and optimized according to a 3-level, 3-factor Box-Behnken experimental design. The dependent variables, fill volume, hydroxypropylmethylcellulose (HPMC) concentration, and glycerol concentration, were assessed for their effects on measured responses, disintegration time, work of adhesion, force of adhesion, dissolution area under curve (AUC) at 1 minute, and permeation AUC at 3 minutes. Physicochemical and physicomechanical properties of the developed system were studied by rheology, FTIR, toughness determination, mucoadhesion, and nanotensile testing. Data obtained from the physicomechanical characterization confirmed the suitability of NFMS for application in oramucosal drug delivery. The optimized NFMS showed the drug entrapment of 2.3 mg/1.5 cm2with disintegration time of 12.8 seconds. Electrospinning of drug-loaded polyvinylalcohol (PVA) fibers resulted in a matrix with an exceedingly high surface-area-to-volume ratio, which enhanced the rate of dissolution for rapid oramucosal drug delivery. To corroborate with the experimental studies, the incorporation of glycerol with HPMC and PVA blend was mechanistically elucidated using computer-assisted modeling of the 3D polymeric architecture of the respective molecular complexes to envisage the likely alignment of the polymer morphologies affecting the performance of the nanofibrous device.

scholarly journals Basic Potential of Carbon Nanotubes in Tissue Engineering Applications

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Hisao Haniu ◽  
Naoto Saito ◽  
Yoshikazu Matsuda ◽  
Tamotsu Tsukahara ◽  
Yuki Usui ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Tissue Engineering ◽  
High Surface ◽  
High Surface Area ◽  
Volume Ratio ◽  
Medical Application ◽  
Mechanical And Thermal Properties ◽  
Biological Responses

Carbon nanotubes (CNTs) are attracting interest in various fields of science because they possess a high surface area-to-volume ratio and excellent electronic, mechanical, and thermal properties. Various medical applications of CNTs are expected, and the properties of CNTs have been greatly improved for use in biomaterials. However, the safety of CNTs remains unclear, which impedes their medical application. Our group is evaluating the biological responses of multiwall CNTs (MWCNTs)in vivoandin vitrofor the promotion of tissue regeneration as safe scaffold materials. We recently showed that intracellular accumulation is important for the cytotoxicity of CNTs, and we reported the active physiological functions CNTs in cells. In this review, we describe the effects of CNTsin vivoandin vitroobserved by our group from the standpoint of tissue engineering, and we introduce the findings of other research groups.

scholarly journals Biosynthesis and characterization of gold nanoparticles using Brazilian red propolis and evaluation of its antimicrobial and anticancer activities

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
C. E. A. Botteon ◽  
L. B. Silva ◽  
G. V. Ccana-Ccapatinta ◽  
T. S. Silva ◽  
S. R. Ambrosio ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Antimicrobial Agents ◽  
Low Cost ◽  
High Surface ◽  
High Surface Area ◽  
Volume Ratio ◽  
Antimicrobial Activities ◽  
Biological Properties ◽  
Anticancer Activities

AbstractGold nanoparticles (AuNPs) are highlighted due to their low toxicity, compatibility with the human body, high surface area to volume ratio, and surfaces that can be easily modified with ligands. Biosynthesis of AuNPs using plant extract is considered a simple, low-cost, and eco-friendly approach. Brazilian Red Propolis (BRP), a product of bees, exhibits anti-inflammatory, anti-tumor, antioxidant, and antimicrobial activities. Here, we described the biosynthesis of AuNPs using BRP extract (AuNPextract) and its fractions (AuNPhexane, AuNPdichloromethane, AuNPethyl acetate) and evaluated their structural properties and their potential against microorganisms and cancer cells. AuNPs showed a surface plasmon resonance (SPR) band at 535 nm. The sizes and morphologies were influenced by the BRP sample used in the reaction. FTIR and TGA revealed the involvement of bioactive compounds from BRP extract or its fractions in the synthesis and stabilization of AuNPs. AuNPdichloromethane and AuNPhexane exhibited antimicrobial activities against all strains tested, showing their efficacy as antimicrobial agents to treat infectious diseases. AuNPs showed dose-dependent cytotoxic activity both in T24 and PC-3 cells. AuNPdichloromethane and AuNPextract exhibited the highest in vitro cytotoxic effect. Also, the cytotoxicity of biogenic nanoparticles was induced by mechanisms associated with apoptosis. The results highlight a potential low-cost green method using Brazilian red propolis to synthesize AuNPs, which demonstrated significant biological properties.

scholarly journals Spatiotemporal controlled delivery of nanoparticles to injured vasculature

2010 ◽  
Vol 107 (5) ◽  
pp. 2213-2218 ◽  
Author(s):  
Juliana M. Chan ◽  
Liangfang Zhang ◽  
Rong Tong ◽  
Debuyati Ghosh ◽  
Weiwei Gao ◽  
...  
Keyword(s):  
Drug Release ◽  
High Surface ◽  
Volume Ratio ◽  
Hybrid Nanoparticles ◽  
Phage Library ◽  
Optimal Size ◽  
Systemic Delivery ◽  
Cell Surface Antigens

There are a number of challenges associated with designing nanoparticles for medical applications. We define two challenges here: (i) conventional targeting against up-regulated cell surface antigens is limited by heterogeneity in expression, and (ii) previous studies suggest that the optimal size of nanoparticles designed for systemic delivery is approximately 50–150 nm, yet this size range confers a high surface area-to-volume ratio, which results in fast diffusive drug release. Here, we achieve spatial control by biopanning a phage library to discover materials that target abundant vascular antigens exposed in disease. Next, we achieve temporal control by designing 60-nm hybrid nanoparticles with a lipid shell interface surrounding a polymer core, which is loaded with slow-eluting conjugates of paclitaxel for controlled ester hydrolysis and drug release over approximately 12 days. The nanoparticles inhibited human aortic smooth muscle cell proliferation in vitro and showed greater in vivo vascular retention during percutaneous angioplasty over nontargeted controls. This nanoparticle technology may potentially be used toward the treatment of injured vasculature, a clinical problem of primary importance.

A Cervico-Thoraco-Lumbar Multibody Dynamic Model for the Estimation of Joint Loads and Muscle Forces

2015 ◽  
Vol 137 (11) ◽  
Author(s):  
Tsolmonbaatar Khurelbaatar ◽  
Kyungsoo Kim ◽  
Yoon Hyuk Kim
Keyword(s):  
Facet Joint ◽  
Experimental Studies ◽  
Contact Forces ◽  
Cervical Region ◽  
Computational Studies ◽  
Muscle Forces ◽  
Facet Joints ◽  
Whole Spine ◽  
Joint Loads

Computational musculoskeletal models have been developed to predict mechanical joint loads on the human spine, such as the forces and moments applied to vertebral and facet joints and the forces that act on ligaments and muscles because of difficulties in the direct measurement of joint loads. However, many whole-spine models lack certain elements. For example, the detailed facet joints in the cervical region or the whole spine region may not be implemented. In this study, a detailed cervico-thoraco-lumbar multibody musculoskeletal model with all major ligaments, separated structures of facet contact and intervertebral disk joints, and the rib cage was developed. The model was validated by comparing the intersegmental rotations, ligament tensile forces, facet joint contact forces, compressive and shear forces on disks, and muscle forces were to those reported in previous experimental and computational studies both by region (cervical, thoracic, or lumbar regions) and for the whole model. The comparisons demonstrated that our whole spine model is consistent with in vitro and in vivo experimental studies and with computational studies. The model developed in this study can be used in further studies to better understand spine structures and injury mechanisms of spinal disorders.

Transient Analysis of Microorganism Temperature and Evaporative Losses in an Algae Biofilm Photobioreactor

2011 ◽  
Author(s):  
Thomas E. Murphy ◽  
Halil Berberoglu
Keyword(s):  
Ambient Temperature ◽  
Water Loss ◽  
High Surface ◽  
Volume Ratio ◽  
Ambient Air ◽  
Evaporative Water Loss ◽  
Environmental Data ◽  
Biofuel Production ◽  
Solar Irradiation ◽  
Evaporative Water

This study describes the thermal modeling of a novel algal biofilm photobioreactor aimed at cultivating algae for biofuel production. The thermal model is developed to assess the photo-bioreactor’s thermal profile and evaporative water loss rate for a range of environmental parameters, including relative humidity, ambient air temperature, solar irradiation, and wind speed. First, a 24 hour simulation of the system has been performed using environmental data for Memphis, TN, USA on a typical spring day to assess the diurnal variations in system performance. Then, a sensitivity analysis is performed to assess the effect of each environmental parameter on the temperature and evaporative losses of the photobioreactor. It is observed that because of the high surface area-to-volume ratio of the system, the temperature of the system exceeds that of the maximum ambient temperature during daylight hours by approximately 0.5 °C and is lower than the minimum ambient temperature at night by approximately 1.4 °C because of evaporative and radiative cooling. Furthermore, without active cooling, the characteristic evaporative water loss from the system is approximately 4.8 L/m2-day.

scholarly journals Bio-nano interactions: binding proteins, polysaccharides, lipids and nucleic acids onto magnetic nanoparticles

2021 ◽  
Vol 25 (1) ◽  
Author(s):  
Lucía Abarca-Cabrera ◽  
Paula Fraga-García ◽  
Sonja Berensmeier
Keyword(s):  
Nucleic Acids ◽  
Driving Forces ◽  
Structural Characteristics ◽  
Low Cost ◽  
High Surface ◽  
Experimental Studies ◽  
Volume Ratio ◽  
Functionalized Surfaces ◽  
Major Interest ◽  
Future Work

AbstractThe major interest in nanoparticles as an application platform for biotechnology arises from their high surface-to-volume ratio. Iron oxide nanoparticles (IONPs) are particularly appealing due to their superparamagnetic behavior, which enables bioseparation using external magnetic fields. In order to design advanced biomaterials, improve binding capacities and develop innovative processing solutions, a thorough understanding of the factors governing organic-inorganic binding in solution is critical but has not yet been achieved, given the wide variety of chemical and physical influences. This paper offers a critical review of experimental studies of the interactions between low cost IONPs (bare iron oxides, silica-coated or easily-functionalized surfaces) and the main groups of biomolecules: proteins, lipids, nucleic acids and carbohydrates. Special attention is devoted to the driving forces and interdependencies responsible of interactions at the solid-liquid interface, to the unique structural characteristics of each biomolecular class, and to environmental conditions influencing adsorption. Furthermore, studies focusing on mixtures, which are still rare, but absolutely necessary to understand the biocorona, are also included. This review concludes with a discussion of future work needed to fill the gaps in knowledge of bio-nano interactions, seeking to improve nanoparticles’ targeting capabilities in complex systems, and to open the door for multipurpose recognition and bioseparation processes.

scholarly journals Quantum Simulation of the Silicene and Germanene for Sensing and Sequencing of DNA/RNA Nucleobases

Biosensors ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 59
Author(s):  
Hikmet Hakan Gürel ◽  
Bahadır Salmankurt
Keyword(s):  
Density Functional ◽  
2D Materials ◽  
High Surface ◽  
Experimental Studies ◽  
Interaction Mechanism ◽  
Volume Ratio ◽  
First Principle ◽  
Functional Theory ◽  
Silicon And Germanium ◽  
Insight Into

Over the last decade, we have been witnessing the rise of two-dimensional (2D) materials. Several 2D materials with outstanding properties have been theoretically predicted and experimentally synthesized. 2D materials are good candidates for sensing and detecting various biomolecules because of their extraordinary properties, such as a high surface-to-volume ratio. Silicene and germanene are the monolayer honeycomb structures of silicon and germanium, respectively. Quantum simulations have been very effective in understanding the interaction mechanism of 2D materials and biomolecules and may play an important role in the development of effective and reliable biosensors. This article focuses on understanding the interaction of DNA/RNA nucleobases with silicene and germanane monolayers and obtaining the possibility of using silicene and germanane monolayers as a biosensor for DNA/RNA nucleobases’ sequencing using the first principle of Density Functional Theory (DFT) calculations with van der Waals (vdW) correction and nonequilibrium Green’s function method. Guanine (G), Cytosine (C), Adenine (A), Thymine (T), and Uracil (U) were examined as the analytes. The strength of adsorption between the DNA/RNA nucleobases and silicene and germanane is G > C > A > T > U. Moreover, our recent work on the investigation of Au- and Li-decorated silicene and germanane for detection of DNA/RNA nucleobases is presented. Our results show that it is possible to get remarkable changes in transmittance due to the adsorption of nucleobases, especially for G, A, and C. These results indicate that silicene and germanene are both good candidates for the applications in fast sequencing devices for DNA/RNA nucleobases. Additionally, our present results have the potential to give insight into experimental studies and can be valuable for advancements in biosensing and nanobiotechnology.

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