In book: Ferulic Acid: Antioxidant Properties, Uses and Potential Health Benefits, Edition: 1, Chapter: 2, Publisher: Nova Science Publishers. The use and potential commercial application of biosurfactants in the medical field has increased during the past decade. Their antibacterial, antifungal and. Remains of any nature are potential candidates for aDNA recovery and almost all of Ancient Plant Remains: Findings, Uses and Potential Applications for the.
Applications Potential Use &
In May a boric acid -infused, laser-induced graphene supercapacitor tripled its areal energy density and increased its volumetric energy density fold.
The new devices proved stable over 12, charge-discharge cycles, retaining 90 percent of their capacitance. In stress tests, they survived 8, bending cycles. Silicon-graphene anode lithium ion batteries were demonstrated in Stable Lithium ion cycling was demonstrated in bi- and few layer graphene films grown on nickel substrates ,  while single layer graphene films have been demonstrated as a protective layer against corrosion in battery components such as the battery case.
Researchers built a lithium-ion battery made of graphene and silicon , which was claimed to last over a week on one charge and took only 15 minutes to charge. In argon-ion based plasma processing was used to bombard graphene samples with argon ions.
That knocked out some carbon atoms and increased the capacitance of the materials three-fold. Graphene does not oxidize in air or in biological fluids, making it an attractive material for use as a biosensor. Of the various types of graphene sensors that can be made, biosensors were the first to be available for sale.
In researchers proposed an in-plane pressure sensor consisting of graphene sandwiched between hexagonal boron nitride and a tunneling pressure sensor consisting of h-BN sandwiched by graphene. This structure is insensitive to the number of wrapping h-BN layers, simplifying process control.
Because h-BN and graphene are inert to high temperature, the device could support ultra-thin pressure sensors for application under extreme conditions. In researchers demonstrated a biocompatible pressure sensor made from mixing graphene flakes with cross-linked polysilicone found in silly putty. Nanoelectromechanical systems NEMS can be designed and characterized by understanding the interaction and coupling between the mechanical, electrical, and the van der Waals energy domains.
Quantum mechanical limit governed by Heisenberg uncertainty relation decides the ultimate precision of nanomechanical systems. Quantum squeezing can improve the precision by reducing quantum fluctuations in one desired amplitude of the two quadrature amplitudes. Traditional NEMS hardly achieve quantum squeezing due to their thickness limits. A scheme to obtain squeezed quantum states through typical experimental graphene NEMS structures taking advantages of its atomic scale thickness has been proposed.
Theoretically graphene makes an excellent sensor due to its 2D structure. The fact that its entire volume is exposed to its surrounding environment makes it very efficient to detect adsorbed molecules. However, similar to carbon nanotubes, graphene has no dangling bonds on its surface. Gaseous molecules cannot be readily adsorbed onto graphene surfaces, so intrinsically graphene is insensitive. The thin polymer layer acts like a concentrator that absorbs gaseous molecules.
The molecule absorption introduces a local change in electrical resistance of graphene sensors. While this effect occurs in other materials, graphene is superior due to its high electrical conductivity even when few carriers are present and low noise, which makes this change in resistance detectable. Density functional theory simulations predict that depositing certain adatoms on graphene can render it piezoelectrically responsive to an electric field applied in the out-of-plane direction.
This type of locally engineered piezoelectricity is similar in magnitude to that of bulk piezoelectric materials and makes graphene a candidate for control and sensing in nanoscale devices. Promoted by the demand for wearable devices, graphene has been proved to be a promising material for potential applications in flexible and highly sensitive strain sensors.
An environment-friendly and cost-effective method to fabricate large-area ultrathin graphene films is proposed for highly sensitive flexible strain sensor. Rubber bands infused with graphene "G-bands" can be used as inexpensive body sensors. The bands remain pliable and can be used as a sensor to measure breathing, heart rate, or movement.
Lightweight sensor suits for vulnerable patients could make it possible to remotely monitor subtle movement. Gauge factors of up to 35 were observed. Such sensors can function at vibration frequencies of at least Hz.
In researchers announced a graphene-based magnetic sensor times more sensitive than an equivalent device based on silicon 7, volts per amp-tesla. The sensor substrate was hexagonal boron nitride. The sensors were based on the Hall effect , in which a magnetic field induces a Lorentz force on moving electric charge carriers, leading to deflection and a measurable Hall voltage.
In the worst case graphene roughly matched a best case silicon design. In the best case graphene required lower source current and power requirements. Graphene oxide is non-toxic and biodegradable.
Its surface is covered with epoxy, hydroxyl, and carboxyl groups that interact with cations and anions. It is soluble in water and forms stable colloid suspensions in other liquids because it is amphiphilic able to mix with water or oil. Dispersed in liquids it shows excellent sorption capacities. It can remove copper, cobalt, cadmium , arsenate , and organic solvents.
Research suggests that graphene filters could outperform other techniques of desalination by a significant margin. Instead of allowing the permeation, blocking is also necessary. Gas permeation barriers are important for almost all applications ranging from food, pharmaceutical, medical, inorganic and organic electronic devices, etc.
It enhances life of the product and allow keeping the total thickess of devices small. Being atomically thin, defectless graphene is immpermeable to all gases. Graphene accommodates a plasmonic surface mode,  observed recently via near field infrared optical microscopy techniques   and infrared spectroscopy  Potential applications are in the terahertz to mid-infrared frequencies,  such as terahertz and midinfrared light modulators, passive terahertz filters, mid-infrared photodetectors and biosensors.
Scientists discovered using graphene as a lubricant works better than traditionally used graphite. A one atom thick layer of graphene in between a steel ball and steel disc lasted for 6, cycles. Conventional lubricants lasted 1, cycles. For example, graphene could be used as a coating for buildings or windows to block radio waves.
Absorption is a result of mutually coupled Fabry—Perot resonators represented by each graphene-quartz substrate. A repeated transfer-and-etch process was used to control surface resistivity.
Graphene oxide can be reversibly reduced and oxidized via electrical stimulus. Controlled reduction and oxidation in two-terminal devices containing multilayer graphene oxide films are shown to result in switching between partly reduced graphene oxide and graphene, a process that modifies electronic and optical properties.
Oxidation and reduction are related to resistive switching. A graphene-based plasmonic nano-antenna GPN can operate efficiently at millimeter radio wavelengths. The wavelength of surface plasmon polaritons for a given frequency is several hundred times smaller than the wavelength of freely propagating electromagnetic waves of the same frequency.
These speed and size differences enable efficient graphene-based antennas to be far smaller than conventional alternatives. The latter operate at frequencies times larger than GPNs, producing.
An electromagnetic EM wave directed vertically onto a graphene surface excites the graphene into oscillations that interact with those in the dielectric on which the graphene is mounted, thereby forming surface plasmon polaritons SPP.
Potential uses include smart dust , low-power terabit wireless networks  and photonics. A nanoscale gold rod antenna captured and transformed EM energy into graphene plasmons, analogous to a radio antenna converting radio waves into electromagnetic waves in a metal cable. The plasmon wavefronts can be directly controlled by adjusting antenna geometry. The waves were focused by curving the antenna and refracted by a prism-shaped graphene bilayer because the conductivity in the two-atom-thick prism is larger than in the surrounding one-atom-thick layer.
The plasmonic metal-graphene nanoantenna was composed by inserting a few nanometers of oxide between a dipole gold nanorod and the monolayer graphene. With tuning the chemical potential of the graphene layer through field effect transistor architecture, the in-phase and out-phase mode coupling between graphene palsmonics and metal plasmonics is realized.
Graphene's light weight provides relatively good frequency response , suggesting uses in electrostatic audio speakers and microphones. One application was as a radio replacement for long-distance communications, given sound's ability to penetrate steel and water, unlike radio waves. Graphene could potentially usher in a new generation of waterproof devices whose chassis may not need to be sealed like today's devices.
Graphene's high thermal conductivity suggests that it could be used as an additive in coolants. Graphene's properties suggest it as a reference material for characterizing electroconductive and transparent materials. One layer of graphene absorbs 2. This property was used to define the conductivity of transparency that combines sheet resistance and transparency.
This parameter was used to compare materials without the use of two independent parameters. In , researchers reported that a three-dimensional, vertically aligned, functionalized multilayer graphene architecture can be an approach for graphene-based thermal interfacial materials TIMs with superior thermal conductivity and ultra-low interfacial thermal resistance between graphene and metal. Graphene-metal composites can be used in thermal interface materials.
This suggests the possibility of using them for semiconductor interconnects in computer chips. High temperature chemical vapor deposition stimulates grain size growth in copper films. The larger grain sizes improve heat conduction. The heat conduction improvement was more pronounced in thinner copper films, which is useful as copper interconnects shrink.
This is because of enhanced in-plane heat conduction resulting from the simultaneous increase of thermal resistance between the graphene and the substrate, which limited cross-plane phonon scattering. Heat spreading ability doubled. However, mismatches at the boundary between horizontally adjacent crystals reduces heat transfer by a factor of Graphene's strength, stiffness and lightness suggested it for use with carbon fiber. Graphene has been used as a reinforcing agent to improve the mechanical properties of biodegradable polymeric nanocomposites for engineering bone tissue.
In , researchers at the University of Western Australia discovered nano sized fragments of graphene can speed up the rate of chemical reactions. The new material was claimed to approach the efficiency of platinum catalysts.
The approach eliminated the need for less efficient iron nanoparticles. In laboratory tests, the leading edge of a helicopter rotor blade was coated with the composite, covered by a protective metal sleeve.
From Wikipedia, the free encyclopedia. This article needs to be updated. The results of their prospective cohort study illustrate the potential of a bespoke smartphone application to collect geospatially localized data from short-term travellers to South East Asia, rather than relying on retrospective paper-based questionnaires, typically administered at international airports, 9 which are subject to recall bias.
The authors point to the high acceptability of their mHealth survey tool among travellers. The researchers suggest that mHealth technology may be especially useful in travellers with chronic medical illness, many of whom have multiple complex comorbidities. Despite concerns over data protection, participant user fatigue and data overload, the benefits of mHealth surely outweigh the risks which should be reduced over time as the technology is refined.
Larger sample sizes and the possibility of capturing real-world, real-time data should reduce research costs and enrich the evidence base for travel health recommendations by providing more accurate incidence rates for a range of travel health problems. Such data would allow travel health providers to personalize the pre-travel health advice they provide and would increase the efficiency of the travel health consultation where a great deal of undifferentiated advice is offered to travellers.
We eagerly await the results of follow-up studies but this preliminary study heralds an exciting new era in travel medicine research. Oxford University Press is a department of the University of Oxford.
It furthers the University's objective of excellence in research, scholarship, and education by publishing worldwide. Sign In or Create an Account. Close mobile search navigation Article navigation. Research on the move: Identification and review of mobile applications for travel medicine practitioners and patients. Fundamentals for future mobile-health mHealth: Paederus dermatitis in a seafarer diagnosed via telemedicine collaboration.
Mesenchymal stem cells MSCs are derived from adult stem cells; they are multipotent and exert anti-inflammatory and immunomodulatory effects.
They can differentiate into multiple cell types of the mesenchyme, for example, endothelial cells, osteoblasts, chondrocytes, fibroblasts, tenocytes, vascular smooth muscle cells, and sarcomere muscular cells. MSCs are easily obtained and can be cultivated and expanded in vitro; thus, they represent a promising and encouraging treatment approach in orthopedic surgery. Here, we review the application of MSCs to various orthopedic conditions, namely, orthopedic trauma; muscle injury; articular cartilage defects and osteoarthritis; meniscal injuries; bone disease; nerve, tendon, and ligament injuries; spinal cord injuries; intervertebral disc problems; pediatrics; and rotator cuff repair.
The use of MSCs in orthopedics may transition the practice in the field from predominately surgical replacement and reconstruction to bioregeneration and prevention. However, additional research is necessary to explore the safety and effectiveness of MSC treatment in orthopedics, as well as applications in other medical specialties. Very few tissues and organs can spontaneously regenerate following disease or trauma, and this regenerative capacity diminishes during the lifetime. As such, scientists are developing techniques in the fields of tissue engineering, cell therapy, and regenerative medicine to aid the regeneration of the musculoskeletal system.
Stem cell SC use in orthopedic surgery has the potential to change the field of orthopedics from one dominated by surgical replacement and reconstruction to one of bioregeneration and prevention [ 1 ]. Around the s, a unique group of bone marrow cells was discovered with the capability to differentiate into various other cells [ 2 , 3 ]. However, we now know that several types of SCs exist, each with different characteristics—including embryonic stem cells ESCs , fetal stem cells FSCs , infant stem cells, and adult stem cells, from which mesenchymal stem cells MSCs derive [ 4 ].
Adult and fetal SCs are considered to be undifferentiated; they can be found in adult tissues and in the fetus, respectively [ 4 ]. Various legal, ethical, physiological, and immunologic concerns are associated with the use of ESCs and FSCs, which have limited their application [ 5 ].
Nevertheless, most medical specialties can benefit from the progress in SC research and regenerative medicine. More than trials regarding SC research in musculoskeletal diseases are currently underway [ 5 ]. There are multiple clinical opportunities for SCs in orthopedic surgery, ranging from tissue regeneration and modulation of the immune function, to the modeling of rare diseases [ 5 ].
MSCs can be obtained from the umbilical cord, amniotic fluid, placenta, adipose tissue, joint synovium, synovial fluid, dental pulp, endosteum, and periosteum [ 2 — 4 , 6 , 7 ]. One theory for the varied locations of SCs is that these cells derive from pericytes [ 9 — 11 ]. Moreover, MSCs are multipotent, meaning they can differentiate into multiple mesenchymal cell types—including endothelial cells, osteoblasts, chondrocytes, fibroblasts, tenocytes, vascular smooth muscle cells, myoblasts, and neurons Figure 1.
Recent publications report that MSCs can also differentiate into nonmesodermal cells—such as neurons, astrocytes, and hepatocytes—in vitro [ 3 , 12 , 13 ]. Further, by being reservoirs of repair cells, exerting immunomodulatory and anti-inflammatory effects, endogenous MSCs contribute to the preservation of healthy tissues [ 14 ].
As already mentioned, MSCs can be obtained from virtually any tissue in the body. For regenerative medicine and tissue engineering purposes, MSCs are usually obtained from the bone marrow, which has an MSC content of approximately 1: The prevalence of MSCs in the peripheral circulation is much lower, around 1: Obtaining the bone marrow aspirate is an invasive procedure that regularly necessitates general anesthesia and can be associated with pain, discomfort, and complications [ 6 , 7 ].
Therefore, SC research has focused on identifying agents that promote MSC egress from the bone marrow into the peripheral circulation to facilitate their obtention and isolation. The most widely used agent is the granulocyte colony-stimulating factor G-CSF filgrastim, which is usually given by subcutaneous injection in conjunction with chemotherapy in hematological cancer patients [ 13 , 15 ].
Consequently, MSCs are mobilized from the bone marrow stroma to the peripheral circulation [ 9 , 12 , 13 , 15 ]. The blood is then obtained from the peripheral circulation, and MSCs are isolated, expanded, differentiated, and seeded on scaffolds Figure 2. In , the International Society for Cellular Therapy recommended that cells should fulfill the following criteria to be considered as MSCs: MSCs possess immunomodulatory and immunosuppressive properties via the secretion of specific cytokines and can thus modulate inflammation following an injury [ 13 ].
MSCs are hypoimmunogenic and can evade the host immune system. MSCs have the ability to interact with immune cells and can suppress and modulate alloreactivity.
Nevertheless, these immunomodulatory and immunosuppressive properties have not been completely established in orthopedic applications. One of the issues related with regenerative cell-based therapies is the risk of tumor formation. However, in , Hernigou and colleagues completed a This suggests that the application of these cells is somewhat safe and it does not increase the risk of tumor formation.
This review will discuss the major current and potential future applications of MSCs in orthopedic surgery. The endosteum and periosteum are rich sources of osteochondral progenitor cells during fracture healing [ 18 ]. Grafting experiments revealed that the transplanted periosteum generates both osteoblasts and chondrocytes during fracture repair, whereas the endosteum generates primarily osteoblasts [ 18 ]. In addition, bone morphogenetic protein BMP -2 has been shown to stimulate chondrogenesis within the periosteum, but not in the endosteum, indicating that cells within these sites may be activated by different factors [ 13 , 18 ].
Fracture healing is an intricate process that occurs through a combination of endochondral and intramembranous ossification [ 19 ]. During endochondral ossification mechanism, a cartilage template is initially formed and subsequently replaced by osteoblasts delivered to the fracture site as a result of angiogenesis [ 19 ].
Recent work has also shown that hypertrophic chondrocytes in the fracture callus may persist and transdifferentiate into osteoblasts [ 20 , 21 ]. Thus, the potential application of these mechanisms in bone healing treatments, for example, therapeutic stimulation of the conversion of chondrocytes into osteoblasts in cases of hypertrophic nonunion should be researched further [ 20 , 21 ]. Cells that contribute to the healing of a fracture can be mobilized from the circulation [ 13 ].
Nevertheless, research suggests that these circulating cells account for only a small number of cells in the fracture callus under normal circumstances, suggesting that the majority of the cells at the fracture site migrated from the adjacent tissues [ 13 ]. As such, therapeutic amplification of circulating MSCs through their mobilization could also represent a potential therapeutic opportunity in fracture repair [ 13 ].
MSCs also comprise one therapeutic opportunity in such fracture complications as delayed union or nonunion. Some authors, for example, Hernigou et al. The aspirates were implanted exactly at the site of nonunion, leading to callus formation.
Although promising, the effective dose of cells required for a successful treatment remains to be demonstrated [ 13 , 21 ]. Following skeletal muscle injury, complete functional recovery remains challenging and this recovery is delayed by the development of scar tissue. The regenerative capacity of skeletal muscle is low and mainly brought about by mononucleated precursor cells satellite cells [ 1 ]. Satellite cells are situated under the basal lamina that envelops every myofiber and exhibit SC-like characteristics during the repair of muscle injury [ 23 — 25 ].
Accordingly, the use of satellite cells represents a very appealing strategy to treat muscle disorders and injuries because of their intrinsic myogenic potential [ 23 — 25 ]. However, in vitro expansion of these cells is difficult as they rapidly senesce and display poor posttransplantation survival [ 22 — 25 ].
Bone marrow-derived mesenchymal SCs BMDMSCs have the ability to differentiate and blend with myoblast s in vitro and contribute to the healing process of the muscle [ 24 , 25 ]. For example, they are easily accessible, more abundant and proliferative, and secrete several angiogenic and antiapoptotic cytokines that sustain tissue regeneration and reduce harm.
Tetanic muscle force was evaluated 2 and 4 weeks after the injection, and histological examination was performed to establish the deposition of collagen in the muscle and the number of centronucleated muscle fibers. The authors showed that the tetanus force and the amount of centronucleated myofibers were superior in the treated group in comparison with the control group [ 23 , 24 ]. They concluded that muscle repair and force were enhanced by ADMSC therapy 2 weeks after the treatment, suggestive that ADMSC administration could indeed accelerate muscle repair [ 22 ].
Upon implantation into the skeletal muscle, MDMSCs show longer-term survival than myoblasts and directly cooperate in the regeneration of myofibers [ 25 ]. Studies suggest that MDMSCs are also able to differentiate into endothelial and neural lineages in vivo, which may improve the neural and vascular supply to the regenerating muscle [ 25 , 26 ]. Evidence from recent studies suggests that inflammatory pathways and signaling may affect muscle healing [ 26 ].
Numerous anti-inflammatory agents are employed following an injury, including nonsteroidal anti-inflammatory drugs NSAIDs that are typically prescribed for pain control. These contradictory findings indicate that prudence should be exercised concerning the use of NSAIDs and cyclooxygenase-2 inhibitors after injury [ 26 ].
Articular cartilage lesions are one of the most frequent problems encountered by orthopedic surgeons [ 27 ]. Due to the relative acellularity and the specific biochemical properties of the cartilage, the self-renewal potential of this tissue is very limited [ 27 , 28 ]. An orthopedist may use numerous techniques to treat articular cartilage lesions; however, none of the currently available surgical treatments for cartilage repair provides a tissue with the biomechanical and biochemical properties of native cartilage [ 4 , 27 , 28 ].
Microfractures—and a more recently developed nanofracture technique—are often employed to treat articular cartilage lesions. The aim of these bone-marrow stimulation techniques is to perform small perforations in the subchondral bone, releasing SCs from the bone marrow [ 4 ].
Unfortunately, the created neotissue is fibrocartilage, which differs in biomechanical and biochemical characteristics from that of the hyaline cartilage. The durability of the repaired tissue is also lower than that of native cartilage [ 26 , 27 ]. More recent techniques aim to regenerate the cartilage, such as autologous chondrocyte implantation ACI [ 28 , 29 ], using various cell types—including SCs, chondrocytes, SCs with periosteum, chondrocyte precursors, or a combination of these [ 4 ].
A recent laboratory study confirmed that autologous chondroprogenitor cells were more effective in healing articular cartilage defects as compared to allogenic cells [ 4 ]. Using a bovine model, Zhou et al. These chondrogenic progenitor cells showed a predisposition to overexpress chemokines that encouraged chemotaxis of immune cells, suggestive that they interfere with inflammation after cartilage injury [ 30 — 32 ].
Moreover, transplantation of synovial-MSCs SMSCs in rabbits resulted in abundant cartilage matrix development at defect sites as described by Koga et al. This investigation supports the multilineage differentiation potential of SMSCs in vivo depending on the local microenvironments [ 32 , 33 ].
Furthermore, SMSCs were shown to promote cartilage regeneration upon transplantation into a full-thickness articular cartilage defect in a porcine model as early as 3 months subsequent to the procedure, evaluated by magnetic resonance, arthroscopic, and histologic examination [ 34 ]. In an equine model, the application of an autologous platelet-enriched fibrin scaffold to a full-thickness chondral defect of the knee resulted in repair of the cartilage defect, as evidenced by arthroscopy, magnetic resonance imaging T2 mapping, histology, biomechanical testing, and microcomputed tomography [ 35 ].
Also using an equine model, Frisbie et al. Arthroscopic, imaging and microscopy analyses after a month follow-up period revealed that tissue repair was significantly more advanced in horses treated with autologous cells and fibrin than in the two other treatment groups [ 36 ].
Interestingly, in humans, the quantity of SMSCs in the synovial fluid seems to augment in the knees with osteoarthritis, degenerated cartilage, meniscus damage, and subsequent to intra-articular ligament injury [ 37 ], raising the inquiry if the amount of SMSCs mobilized from the synovium to the synovial fluid raises proportionally to the extent of cartilage degeneration as an element of the reparative mechanism [ 32 , 37 ].
The human infrapatellar fat pad is a rich source of MSCs that can be easily harvested during arthroscopic procedures [ 38 ]. Infrapatellar fat pad-derived MSCs isolated from osteoarthritic patients are highly clonogenic and their chondrogenesis is similar to that of cells isolated from healthy articular cartilage [ 38 ].
Recent studies report that the biological characteristics of peripheral blood-derived MSCs and human umbilical cord blood-derived MSCs are comparable with BMDMSCs with respect to their ability to repair cartilage defects [ 38 , 39 ]. The effect of platelet-rich plasma PRP on articular chondrocytes has been recently investigated [ 31 ]. Interestingly, PRP—containing a relatively low number of platelets and very few leukocytes—stimulates chondrocyte anabolism, as demonstrated by changes in the expression of type II collagen and aggrecan [ 31 ].
On the other hand, PRP with a high number of both platelets and leukocytes promotes catabolic chondrocyte pathways. Furthermore, Sakata et al. Osteoarthritis profoundly impacts the quality of life and is related with enormous social and economic costs.
The beginning of degenerative changes in the joint is associated with an abnormal activity or diminution of cell reservoirs. This leads to the failure of chondrogenic potential and the prevalence of a fibrogenic chondrocyte phenotype [ 41 ]. Several clinical trials are currently investigating the delivery of MSCs to the knee via an intra-articular injection with the goal of exploiting their anti-inflammatory and immunosuppressive properties for the management of osteoarthritis and rheumatoid arthritis [ 41 , 42 ].
Studies have demonstrated promising outcomes with this procedure. However, the best dose and vehicle of administration have not been well established [ 41 ].
Potential applications of graphene
Introducing dynamic dosimaging: potential applications for MRI-linac Content from this work may be used under the terms of the Creative Commons Attribution . With the rapid development of nanotechnology, potential applications of nanomaterials in medicine have been widely researched in recent. The potential for mHealth to be used as a data collection tool to facilitate the acquisition of accurate, geo-located and time sensitive data has.