Biodegradable nanoparticles (NPs) are gaining increased attention for their ability to serve as a viable carrier for site specific delivery of vaccines, genes, drugs and other biomolecules in the ...body. They offer enhanced biocompatibility, superior drug/vaccine encapsulation, and convenient release profiles for a number of drugs, vaccines and biomolecules to be used in a variety of applications in the field of medicine. In this manuscript, the methods of preparation of biodegradable NPs, different factors affecting optimal drug encapsulation, factors affecting drug release rates, various surface modifications of nanoparticles to enhance in-vivo circulation, distribution and multimodal functionalities along with the specific applications such as tumor targeting, oral delivery, and delivery of these particles to the central nervous system have been reviewed.
Graphene, reduced graphene oxide (rGO) and derived materials have emerged as promising solutions for applications in renewable energy storage/conversion devices. No alternatives are known to ...simultaneously exhibit large specific surface area, high electrical conductivity, good chemical stability, high mechanical strength and flexibility. This review article is a collection of some of the most relevant research efforts published in the last few years focusing on the synthesis and modification of graphene/rGO as well as doped and hybrid bi-dimensional carbon materials. For research on graphene growth, the choice of precursor and physical state (gas, solid or liquid) has been proved to be as important as the environment and synthesis approach. On the other hand, research focused on graphene oxide reduction has relied on the development of simple and efficient techniques for rGO conversion and device structuring. Modifications applied to graphene (during synthesis) or rGO (during reduction) have included doping, decoration with nanoparticles and the formation of composite microstructures. Fabrication of electrodes based on graphene/rGO for application in energy storage and conversion has been reported, including relevant performance data from real devices (supercapacitors, lithium ion batteries, fuel cells or solar cells). This review concludes with a brief discussion of some of the possible directions for promising research in the area of graphene/rGO fabrication for energy conversion and storage devices.
The advance in nanotechnology has enabled us to utilize particles in the size of the nanoscale. This has created new therapeutic horizons, and in the case of silver, the currently available data only ...reveals the surface of the potential benefits and the wide range of applications. Interactions between viral biomolecules and silver nanoparticles suggest that the use of nanosystems may contribute importantly for the enhancement of current prevention of infection and antiviral therapies. Recently, it has been suggested that silver nanoparticles (AgNPs) bind with external membrane of lipid enveloped virus to prevent the infection. Nevertheless, the interaction of AgNPs with viruses is a largely unexplored field. AgNPs has been studied particularly on HIV where it was demonstrated the mechanism of antiviral action of the nanoparticles as well as the inhibition the transmission of HIV-1 infection in human cervix organ culture. This review discusses recent advances in the understanding of the biocidal mechanisms of action of silver Nanoparticles.
Till now, several innovative methods have been developed for the synthesis of graphene materials including mechanical exfoliation, epitaxial growth by chemical vapor deposition, chemical reduction of ...graphite oxide, liquid-phase exfoliation, arc discharge of graphite,
in situ
electron beam irradiation, epitaxial growth on SiC, thermal fusion, laser reduction of polymers sheets and unzipping of carbon nanotubes
etc.
Generally large scale graphene nanosheets are reliably synthesized utilizing other forms of graphene-based novel materials, including graphene oxide (GO), exfoliated graphite oxide (by thermal and microwave), and reduced graphene oxide. The degree of GO reduction and number of graphene layers are minimized mainly by applying two approaches
via
chemical or thermal treatments. The promising and excellent properties together with the ease of processability and chemical functionalization makes graphene based materials especially GO, ideal candidates for incorporation into a variety of advanced functional materials. Chemical functionalization of graphene can be easily achieved, by the introduction of various functional groups. These functional groups help to control and manipulate the graphene surfaces and help to tune the properties of the resulting hybrid materials. Importantly, graphene and its derivatives GO, have been explored in a wide range of applications, such as energy generation/storage, optical devices, electronic and photonic devices, drug delivery, clean energy, and chemical/bio sensors. In this review article, we have incorporated a general introduction of GO, its synthesis, reduction and some selected frontier applications.
In this review article, we describe a general introduction to GO, its synthesis, reduction and some selected frontier applications. Its low cost and potential for mass production make GO a promising building block for functional hybrid materials.
In this paper we extend the classical Bohr’s inequality to the setting of the non-commutative Hardy space H^1 associated with a semifinite von Neumann algebra. As a consequence, we obtain Bohr’s ...inequality for operators in the von Neumann-Schatten class \mathcal C_1 and square matrices of any finite order. Interestingly, we establish that the optimal bound for r in the above mentioned Bohr’s inequality concerning von Neumann-Schatten class is 1/3 whereas it is 1/2 in the case of 2\times 2 matrices and reduces to \sqrt {2}-1 for the case of 3\times 3 matrices. We also obtain a generalization of our above-mentioned Bohr’s inequality for finite matrices where we show that the optimal bound for r, unlike above, remains 1/3 for every fixed order n\times n,\ n\ge 2.
Postharvest diseases cause considerable losses to harvested fruits and vegetables during transportation and storage. Synthetic fungicides are primarily used to control postharvest decay loss. ...However, the recent trend is shifting toward safer and more eco-friendly alternatives for the control of postharvest decays. Of various biological approaches, the use of antagonistic microorganisms is becoming popular throughout the world. Several postharvest diseases can now be controlled by microbial antagonists. Although the mechanism(s) by which microbial antagonists suppress the postharvest diseases is still unknown, competition for nutrients and space is most widely accepted mechanism of their action. In addition, production of antibiotics, direct parasitism, and possibly induced resistance in the harvested commodity are other modes of their actions by which they suppress the activity of postharvest pathogens in fruits and vegetables. Microbial antagonists are applied either before or after harvest, but postharvest applications are more effective than preharvest applications. Mixed cultures of the microbial antagonists appear to provide better control of postharvest diseases over individual cultures or strains. Similarly, the efficacy of the microbial antagonist(s) can be enhanced if they are used with low doses of fungicides, salt additives, and physical treatments like hot water dips, irradiation with ultraviolet light etc. At the international level, different microbial antagonists like
Debaryomyces hansenii Lodder & Krejer-van Rij,
Cryptococcus laurentii Kufferath & Skinner,
Bacillus subtilis (Ehrenberg) Cohn, and
Trichoderma harzianum Rifai, are being used. Biocontrol products like Aspire, BioSave, and Shemer etc., have also been developed and registered. Although the results of this technology are encouraging, we need to continue to explore potential uses on the commercial scale in different corners of the world.
Glioblastomas and brain metastases are highly proliferative brain tumors with short survival times. Previously, using 13C-NMR analysis of brain tumors resected from patients during infusion of ...13C-glucose, we demonstrated that there is robust oxidation of glucose in the citric acid cycle, yet glucose contributes less than 50% of the carbons to the acetyl-CoA pool. Here, we show that primary and metastatic mouse orthotopic brain tumors have the capacity to oxidize 1,2-13Cacetate and can do so while simultaneously oxidizing 1,6-13Cglucose. The tumors do not oxidize U-13Cglutamine. In vivo oxidation of 1,2-13Cacetate was validated in brain tumor patients and was correlated with expression of acetyl-CoA synthetase enzyme 2, ACSS2. Together, the data demonstrate a strikingly common metabolic phenotype in diverse brain tumors that includes the ability to oxidize acetate in the citric acid cycle. This adaptation may be important for meeting the high biosynthetic and bioenergetic demands of malignant growth.
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•13C-acetate can be oxidized by glioblastoma human orthotopic models in vivo•A wide range of brain metastasis orthotopic models can oxidize 13C-acetate in vivo•13C-acetate infused in patients is oxidized by glioblastoma and brain metastases•Acetyl-CoA synthetase 2 is highly expressed in human brain tumors
Oxidation of acetate into the Krebs cycle occurs in primary and metastatic tumors in vivo, indicating acetate as a widespread bioenergetic substrate for cancer progression.
Carbon nanomaterials have huge potential in the field of energy and environmental applications. However, a wide range of greener and environment friendly synthesis methods utilizing natural, ...renewable, cheaper waste materials has to be developed. This will lead to the reduction of green house gases, exploitation of toxic materials and helps in the development of sustainable technologies. In this review, the details progress made in the last ten years concerning the synthesis of new one dimensional (carbon nanotubes CNT, carbon nanofiber) and two dimensional (graphene) carbon based materials using natural precursors and waste materials is summarized. The aim of this review paper is to provide a comprehensive scientific progress of synthesis of graphene and carbon nanotubes using natural precursor and waste materials for the future perspective. This paper also concludes with a brief discussion on the impact of natural precursor for the graphene and CNTs for environment, its toxicological effects and its future prospects in this rapidly emerging field. Natural precursors and waste carbon containing products are emerging as a new class of materials that have efficiency to produce graphene and CNTs. The various synthesis processes of graphene, CNTs and carbon dots has been reported using several natural hydrocarbon precursors (turpentine oil, eucalyptus oil, palm oil, neem oil, sunflower oil, castor oil, biodiesel, tea-tree extract, honey, milk, sugar, butter, egg etc.). Also, some research groups have used foods wastes (cookie and chocolate), vegetation wastes (woods, leaf, grass, fruit wastes), animal/bird/insect wastes (bone and cow dung, dog feces, chicken feather) and agro waste (sugarcane bagasse) for the synthesis of graphene and CNTs. Research on natural hydrocarbon precursors and wastage materials has increased in recent years as they promise to produce better and high quality of graphene and CNTs in large quantities. The fascinating aspect of this research area is that it guides the use of natural hydrocarbons to explore the possibilities of improving graphene stability and robustness suitable for different type of applications.
Microwave heating reaction time dependent various graphene oxide based zinc oxide (G-ZnO) heterostructures such as graphene oxide-ZnO microcubes (GZMC), graphene oxide-ZnO nanoflakes (GZNF) and ...graphene oxide-ZnO nanoneedles (GZNN) are synthesized by simple and cost effective microwave assisted exfoliation method. These heterostructures supported on graphene oxide nanosheets (GNSs) represent three dimensional (3D) ZnO microcubes and various confined two dimensional (2D) nanoflakes and one dimensional (1D) ZnO nanoneedles like structures. The recorded PL intensity variations show the strong evidence of the interfaces interaction between graphene oxide and ZnO heterostructures. However the differences in the PL intensities are also caused by the 3D and various confined G-ZnO heterostructures. The photoluminescence characterization of GZMC, GZNF and GZNN nanostructures exhibit a decrement in the PL intensity. The PL intensity of the GZNN is lowered by 67.50% and 39.7%to the GZMC and GZNF nanostructures respectively. The results show that ZnO heterostructures grown on GNSs with different morphologies and dimensionalities exhibit the variation in PL intensity due to preventing a direct recombination of the electrons and holes in ZnO. A tentative growth mechanism has been given for the growth of various graphene based zinc oxide heterostructures.
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•G-ZnO heterostructures were synthesized by a simple and cost-effective microwave-assisted method.•ZnO heterostructures were formed on the surface of GNSs.•Tuning of microwave heating time produces the various ZnO nanostructures on GNSs.•Different morphologies of G-ZnO show different PL performances.
Taenia solium is a zoonotic cestode parasite which causes human neurocysticercosis. Pigs transmit the parasite by acting as the intermediate host. An intervention was implemented to control ...transmission of T. solium by pigs in Dalit communities of Banke District, Nepal. Every 3 months, pigs were vaccinated with the TSOL18 recombinant vaccine (Cysvax, IIL, India)) and, at the same time, given an oral treatment with 30mg/kg oxfendazole (Paranthic 10% MCI, Morocco). The prevalence of porcine cysticercosis was determined in both an intervention area as well as a similar no intervention control area, among randomly selected, slaughter-age pigs. Post mortem assessments were undertaken both at the start and at the end of the intervention. Participants conducting the post mortem assessments were blinded as to the source of the animals being assessed. At the start of the intervention the prevalence of porcine cysticercosis was 23.6% and 34.5% in the control and intervention areas, respectively. Following the intervention, the prevalence of cysticercosis in pigs from the control area was 16.7% (no significant change), whereas no infection was detected after complete slicing of all muscle tissue and brain in animals from the intervention area (P = 0.004). These findings are discussed in relation to the feasibility and sustainability of T. solium control. The 3-monthly vaccination and drug treatment intervention in pigs used here is suggested as an effective and practical method for reducing T. solium transmission by pigs. The results suggest that applying the intervention over a period of years may ultimately reduce the number of tapeworm carriers and thereby the incidence of NCC.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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