Titania Nanotubes: Novel Nanostructures for Improved Osseointegration

2010 ◽  
Vol 133 (3) ◽  
Author(s):  
Nathan Swami ◽  
Zhanwu Cui ◽  
Lakshmi S. Nair

Nanostructured one dimensional titanium oxides such as nanotubes and nanowires have raised interest lately due to their unique electronic and optical properties. These materials also have shown significant potential as biomaterials because of their ability to modulate protein and cellular interactions. In this review, synthesis and modification of titania nanotubes have been discussed with emphasis on electrochemical synthesis and wet chemical synthesis and their heat treatment of resulting titania nanotubes. The biomedical applications of titania nanotubes were subsequently discussed in detail with a focus on osseointegration. The areas discussed are cell responses to titania nanotubes, effects of titania nanotubes on stem cell proliferation and differentiation, titania nanotubes as drug delivery vehicles, surface modification of titania nanotubes, and in vivo studies using titania nanotubes. It is concluded that the in vitro and in vivo study clearly demonstrates the efficacy of titania nanotube in enhancing osseointegration of orthopedic implants and much of the future work is expected to focus on improving implant functions by modulating the physical and chemical properties of the nanotubes and by locally delivering bioactive molecules in a sustained manner.

2009 ◽  
Vol 21 (03) ◽  
pp. 149-155 ◽  
Author(s):  
Hsu-Wei Fang

Cartilage injuries may be caused by trauma, biomechanical imbalance, or degenerative changes of joint. Unfortunately, cartilage has limited capability to spontaneous repair once damaged and may lead to progressive damage and degeneration. Cartilage tissue-engineering techniques have emerged as the potential clinical strategies. An ideal tissue-engineering approach to cartilage repair should offer good integration into both the host cartilage and the subchondral bone. Cells, scaffolds, and growth factors make up the tissue engineering triad. One of the major challenges for cartilage tissue engineering is cell source and cell numbers. Due to the limitations of proliferation for mature chondrocytes, current studies have alternated to use stem cells as a potential source. In the recent years, a lot of novel biomaterials has been continuously developed and investigated in various in vitro and in vivo studies for cartilage tissue engineering. Moreover, stimulatory factors such as bioactive molecules have been explored to induce or enhance cartilage formation. Growth factors and other additives could be added into culture media in vitro, transferred into cells, or incorporated into scaffolds for in vivo delivery to promote cellular differentiation and tissue regeneration.Based on the current development of cartilage tissue engineering, there exist challenges to overcome. How to manipulate the interactions between cells, scaffold, and signals to achieve the moderation of implanted composite differentiate into moderate stem cells to differentiate into hyaline cartilage to perform the optimum physiological and biomechanical functions without negative side effects remains the target to pursue.


2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Edward B Neufeld ◽  
Alice Ossoli ◽  
Seth G Thacker ◽  
Boris Vaisman ◽  
Milton Pryor ◽  
...  

Familial lecithin:cholesterol acyltransferase (LCAT) deficiency (FLD) is characterized by low HDL, accumulation of an abnormal cholesterol-rich multilamellar particle called lipoprotein-X (LpX) in plasma, and renal disease. The aim of our study was to determine if LpX is nephrotoxic and to gain insight into the pathogenesis of FLD renal disease. We administered a synthetic LpX, nearly identical to endogenous LpX in its physical, and chemical properties, to wild-type and Lcat -/- mice. Our in vitro and in vivo studies demonstrated an apoA-I and LCAT-dependent pathway for LpX conversion to HDL-like particles, which likely mediates normal plasma clearance of LpX. Plasma clearance of exogenous LpX was markedly delayed in Lcat -/- mice, which have low HDL but only minimal amounts of endogenous LpX and do not spontaneously develop renal disease. Chronically administered exogenous LpX deposited in all renal glomerular cellular and matrical compartments of Lcat -/- mice, and induced proteinuria and nephrotoxic gene changes, as well as all of the hallmarks of FLD renal disease as assessed by histological, TEM, and SEM analyses. Extensive in vivo EM studies revealed LpX uptake by macropinocytosis into mouse glomerular endothelial cells, podocytes, and mesangial cells and delivery to lysosomes, where it was degraded. Endocytosed LpX appeared to be degraded by both human podocyte and mesangial cell lysosomal PLA 2 and induced podocyte secretion of pro-inflammatory IL-6 in vitro and renal Cxl10 expression in Lcat -/- mice. In conclusion, LpX is a nephrotoxic particle that in the absence of LCAT induces all of the histological and functional hallmarks of FLD and hence may serve as a biomarker for monitoring recombinant LCAT therapy. In addition, our studies suggest that LpX-induced loss of endothelial barrier function and release of cytokines by renal glomerular cells likely plays a role in the initiation and progression of FLD nephrosis.


2019 ◽  
Vol 116 (52) ◽  
pp. 26450-26458 ◽  
Author(s):  
Huijun Su ◽  
Shaobo Shi ◽  
Ming Zhu ◽  
Doug Crump ◽  
Robert J. Letcher ◽  
...  

Liquid crystal monomers (LCMs) are used widely in liquid crystal displays (LCDs), which are dramatically changing the world due to the provision of convenient communication. However, there are essentially no published reports on the fate and/or effects of LCMs in the environment. Of 362 currently produced LCMs, 87 were identified as persistent and bioaccumulative (P&B) chemicals, which indicated that these chemicals would exhibit resistance to degradation and exhibit mobility after entering the environment. Following exposure to mixtures of LCM collected from 6 LCD devices, significant modulation of 5 genes,CYP1A4,PDK4,FGF19,LBFABP, andTHRSP, was observed in vitro. Modulation of expressions of mRNAs coding for these genes has frequently been reported for toxic (T) persistent organic pollutants (POPs). In LCM mixtures, 33 individual LCMs were identified by use of mass spectrometry and screened for in 53 samples of dust from indoor environments. LCMs were detectable in 47% of analyzed samples, and 17 of the 33 LCMs were detectable in at least 1 sample of dust. Based on chemical properties, including P&B&T of LCMs and their ubiquitous detection in dust samples, the initial screening information suggests a need for studies to determine status and trends in concentrations of LCMs in various environmental matrices as well as tissues of humans and wildlife. There is also a need for more comprehensive in vivo studies to determine toxic effects and potencies of LCMs during chronic, sublethal exposures.


Cells ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 1232
Author(s):  
Stefania D’Adamo ◽  
Silvia Cetrullo ◽  
Veronica Panichi ◽  
Erminia Mariani ◽  
Flavio Flamigni ◽  
...  

Osteoarthritis (OA) is a disease associated to age or conditions that precipitate aging of articular cartilage, a post-mitotic tissue that remains functional until the failure of major homeostatic mechanisms. OA severely impacts the national health system costs and patients’ quality of life because of pain and disability. It is a whole-joint disease sustained by inflammatory and oxidative signaling pathways and marked epigenetic changes responsible for catabolism of the cartilage extracellular matrix. OA usually progresses until its severity requires joint arthroplasty. To delay this progression and to improve symptoms, a wide range of naturally derived compounds have been proposed and are summarized in this review. Preclinical in vitro and in vivo studies have provided proof of principle that many of these nutraceuticals are able to exert pleiotropic and synergistic effects and effectively counteract OA pathogenesis by exerting both anti-inflammatory and antioxidant activities and by tuning major OA-related signaling pathways. The latter are the basis for the nutrigenomic role played by some of these compounds, given the marked changes in the transcriptome, miRNome, and methylome. Ongoing and future clinical trials will hopefully confirm the disease-modifying ability of these bioactive molecules in OA patients.


10.12737/2753 ◽  
2013 ◽  
Vol 20 (4) ◽  
pp. 160-165
Author(s):  
Сергиевич ◽  
A. Sergievich ◽  
Чайка ◽  
Vladimir Chayka ◽  
Голохваст ◽  
...  

There are both in the domestic and the world science a discussion about the biological activity of water-insoluble solid microparticles technogenous and natural. These interactions are studied in the context of the professional pathology, hygiene and nanotoxicology. The purpose of this research was to study the mechanisms of action of particles of natural minerals of various sizes on biological systems. The paper is based on the applied modern methods which allow to determine the degree of interaction of microelements with the functional systems of the organism. Analysis of the results showed that the application of these methods has a number of shortcomings in the experiments in vivo and in vitro, associated with the physical and chemical features of zeolites. It is established that under cultivation in 6- and 24-hole tablets, the zeolite in a dose of 50 mg/ml covers all the cells attached to the glass. In the fields of view of the cells are practically invisible. Thus, an assessment of toxic effects or functional condition of the cells is not possible. Zeolite being water-insoluble compound wich is not subjected to the pipetting. At the delete zeolite of culture, there is practically full elimination of cells from the hole. Accumulation of the primary information about the biological effects of nano - and microparticles is extremely important. This allows the authors to make some conclusions, but the decision of a question on the mechanism of biological activity, especially the prediction of some properties of particles without the study of physical-chemical properties of the particles isn´t possible.


2015 ◽  
Vol 66 (2) ◽  
pp. 97-108 ◽  
Author(s):  
Veno Kononenko ◽  
Mojca Narat ◽  
Damjana Drobne

Abstract When nanoparticles enter the body, their interactions with cells are almost unavoidable. Unintended nanoparticle interaction with immune cells may elicit a molecular response that can have toxic effects and lead to greater susceptibility to infectious diseases, autoimmune disorders, and cancer development. As evidenced by several studies, nanoparticle interactions with biological systems can stimulate inflammatory or allergic reactions and activate the complement system. Nanoparticles can also stimulate immune response by acting as adjuvants or as haptens. Immunosuppressive effects have also been reported. This article gives a brief review of in vitro and in vivo research evidencing stimulatory or suppressive effects of nanoparticles on the immune system of mammals. In order to ensure safe use of nanosized particles, future research should focus on how their physical and chemical properties influence their behaviour in the biological environment, as they not only greatly affect nanoparticle-immune system interactions but can also interfere with experimental assays


2021 ◽  
Author(s):  
Pedro Ferreira-Santos ◽  
Zlatina Genisheva ◽  
Claudia Botelho ◽  
Cristina Rocha ◽  
José António Teixeira

The significant increase in the world population age, 47 years in 1950 to 73 years in 2020, resulted in an increase in aging related diseases as well as in degenerative diseases. In consequence, researchers have been focusing in the development of new therapies, with a particular emphasis on the use of compounds with antioxidant properties, namely phytochemicals, such as polyphenols and carotenoids. Several in vitro and in vivo studies have demonstrated the phytochemicals antioxidant capacity. Their use is broad, as they can be part of food supplements, medicine and cosmetics. The health benefit of antioxidant phytochemicals is an indisputable question. Phytochemical properties are highly influenced by the natural matrix as well as by extraction process, which have a key role. There are several extraction methods that can be applied depending on the chemical properties of the bioactive compounds. There is a wide range of solvents with different polarities, which allows a selective extraction of the desired target family of compounds. Greener technologies have the advantage to reduce extraction time and solvent quantity in comparison to the most traditional methods. This chapter will focus on the different green extraction strategies related to the recovery of antioxidant bioactive compounds from natural sources, their nutritional and health potential.


2021 ◽  
Vol 37 (1) ◽  
Author(s):  
Jon Petur Joelsson ◽  
Saevar Ingthorsson ◽  
Jennifer Kricker ◽  
Thorarinn Gudjonsson ◽  
Sigurbergur Karason

AbstractVentilator-induced lung injury (VILI) is a serious acute injury to the lung tissue that can develop during mechanical ventilation of patients. Due to the mechanical strain of ventilation, damage can occur in the bronchiolar and alveolar epithelium resulting in a cascade of events that may be fatal to the patients. Patients requiring mechanical ventilation are often critically ill, which limits the possibility of obtaining patient samples, making VILI research challenging. In vitro models are very important for VILI research, but the complexity of the cellular interactions in multi-organ animals, necessitates in vivo studies where the mouse model is a common choice. However, the settings and duration of ventilation used to create VILI in mice vary greatly, causing uncertainty in interpretation and comparison of results. This review examines approaches to induce VILI in mouse models for the last 10 years, to our best knowledge, summarizing methods and key parameters presented across the studies. The results imply that a more standardized approach is warranted.


Crystals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1169
Author(s):  
Ștefan Morărașu ◽  
Ștefan Iacob ◽  
Ionuț Tudorancea ◽  
Sorinel Luncă ◽  
Mihail-Gabriel Dimofte

In the field of oncology, a lot of improvements in nanotechnology creates support for better diagnosis and therapeutic opportunities, and due to their physical and chemical properties, gold nanoparticles are highly applicable. We performed a literature review on the studies engaging the usage of gold nanoparticles on murine models with a focus on the type of the carrier, the chemotherapy drug, the target tumoral tissue and outcomes. We identified fifteen studies that fulfilled our search criteria, in which we analyzed the synthesis methods, the most used chemotherapy conjugates of gold nanoparticles in experimental cancer treatment, as well as the improved impact on tumor size and system toxicity. Due to their intrinsic traits, we conclude that chemotherapy conjugates of gold nanoparticles are promising in experimental cancer treatment and may prove to be a safer and improved therapy option than current alternatives.


Materials ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 1824 ◽  
Author(s):  
Sandra Pina ◽  
Viviana P. Ribeiro ◽  
Catarina F. Marques ◽  
F. Raquel Maia ◽  
Tiago H. Silva ◽  
...  

During the past two decades, tissue engineering and the regenerative medicine field have invested in the regeneration and reconstruction of pathologically altered tissues, such as cartilage, bone, skin, heart valves, nerves and tendons, and many others. The 3D structured scaffolds and hydrogels alone or combined with bioactive molecules or genes and cells are able to guide the development of functional engineered tissues, and provide mechanical support during in vivo implantation. Naturally derived and synthetic polymers, bioresorbable inorganic materials, and respective hybrids, and decellularized tissue have been considered as scaffolding biomaterials, owing to their boosted structural, mechanical, and biological properties. A diversity of biomaterials, current treatment strategies, and emergent technologies used for 3D scaffolds and hydrogel processing, and the tissue-specific considerations for scaffolding for Tissue engineering (TE) purposes are herein highlighted and discussed in depth. The newest procedures focusing on the 3D behavior and multi-cellular interactions of native tissues for further use for in vitro model processing are also outlined. Completed and ongoing preclinical research trials for TE applications using scaffolds and hydrogels, challenges, and future prospects of research in the regenerative medicine field are also presented.


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