Academy of Scientific
Academy of Scientific
News Article | July 20, 2017
Amsterdam, July 20, 2017 - Scientists have found a new way to protect stem cells from harsh inflammation during wound repair. In a study recently published in the journal Cytotherapy, researchers in India discovered that treating mice with a common anti-inflammatory drug called celecoxib promoted stem cell survival and healing when they injected the cells into wounds. The researchers, who are based at the Academy of Scientific & Innovative Research, located at the CSIR-Indian Institute of Chemical Technology, Hyderabad, India, hope that the technique can enhance regenerative therapy for conditions like chronic wounds, where harsh inflammation in the wound can kill the cells used in regenerative stem cell treatments. Stem cell treatments for chronic wounds could be more effective if patients simply took anti-inflammatory drugs during treatment. Chronic wounds are those that don't heal easily. In patients with diabetes, chronic wounds can lead to serious complications and, in some cases, may eventually mean that doctors have to amputate the affected limb. "Curing chronic wounds in patients with diabetes, or in those undergoing chemotherapy and radiotherapy, is a constant challenge," says Amitava Das, senior author of the study. Conventional treatments often don't work, and so scientists are trying to find new ways to heal these stubborn wounds. One potential treatment involves injecting the wound with stem cells, which can change into other cell types, such as skin cells like keratinocytes, to help with the healing process. However, there are hurdles to making this work. "Stem cell therapy holds a lot of promise but it's limited by the harsh injury micro-environment, which is frequently inflamed," says Das. Inflammation is normal in wound healing. As wounds heal, white blood cells, such as those called macrophages, are attracted to the wound site and release substances called cytokines that cause an inflammatory response. At the wound site, enzymes such as cyclooxygenase-2 (COX-2) also become more active and contribute to the inflammation. This inflammation is important in the normal healing process, affecting tissue growth and blood flow changes that allow the tissue to heal; when the inflammation subsides, skin cells start growing to cover the wound and help the tissue knit together. In chronic wounds, however, inflammation can be more extensive and prolonged. This is bad news for any stem cells that might be injected into a chronic wound to help heal it. Stem cells are not like typical drugs - they are alive, and like all life forms, they can die in a hostile environment. The harsh inflammation in chronic wounds kills many of the injected cells, and this is one of the reasons why, so far, stem cells have not worked as a treatment for chronic wounds. Das and his colleagues hypothesized that celecoxib, a common anti-inflammatory drug that selectively inhibits the pro-inflammatory enzyme COX-2, would improve stem cell survival and treatment outcomes for chronic wound therapy. Celecoxib has a similar mechanism of action to other well-known anti-inflammatory drugs you might take for a headache, such as aspirin and ibuprofen, and doctors commonly prescribe it for pain relief. To test their hypothesis, the group used an experimental wound model in mice. The researchers split the mice into four groups. They left a control group completely untreated and treated the second group using mouse stem cells from bone marrow, which they injected into the skin near the wound. They treated a third group orally using celecoxib, and the final group received celecoxib orally, as well as a stem cell injection into the skin near the wound. After a week, the scientists examined the wound tissue for healing and inflammation, and checked if the stem cells had survived. As expected, the wounds showed an inflammatory response over the duration of the experiment. However, the mice treated using both celecoxib and stem cells showed better wound healing and more tissue growth a week later, compared with untreated mice or mice treated using stem cells or celecoxib alone. A significantly higher amount of stem cells had survived and integrated into the wound tissue in mice that had received celecoxib, and there were fewer inflammatory white blood cells and lower levels of cytokines in their wounds, including one cytokine called interleukin-17A. In order to learn more about how celecoxib was enhancing stem cell survival and wound healing, the researchers conducted experiments to identify the cytokines or enzymes directly or indirectly influencing the process. Using macrophages and stem cells grown in a dish, they showed that interleukin-17a was responsible for activating macrophages that might then go on to kill stem cells in the wound. By inhibiting the COX-2 enzyme, and consequently inhibiting interleukin-17A, celecoxib could indirectly prevent macrophages from killing the injected stem cells and instead allow them to heal the wound. So far so good, but did celecoxib have any direct effects on the stem cells themselves? The scientists found that celecoxib directly increased stem cell differentiation into keratinocytes - skin cells required for wound healing. By helping the stem cells to survive and encouraging them to differentiate into skin cells, celecoxib produced a two-pronged healing effect. These results suggest celecoxib, a pain tablet like aspirin, could bring stem cell treatment closer to reality. "With these findings, we could overcome some of the limitations to successful stem cell therapy for chronic wounds," says Das. "I personally feel that the present findings have provided a ray of hope for patients with chronic wounds. We have also been able to identify the molecular targets responsible for these effects, and this could help scientists to identify new drugs that could also help." The article is "Cox-2 inhibition potentiates mouse bone marrow stem cell engraftment and differentiation-mediated wound repair," by Ramasatyaveni Geesala, Neha R. Dhoke and Amitava Das (https:/ ). It appears in Cytotherapy, volume 19, issue 6 (June 2017), published by Elsevier. Copies of this paper are available to credentialed journalists upon request; please contact Elsevier's newsroom at firstname.lastname@example.org or +31 20 485 2492. Cytotherapy is the official journal of the International Society for Cellular Therapy (ISCT). The journal covers science, translational development and treatment with a variety of cell types including haematopoietic stem cells, immune cells (dendritic cells, NK cells, T cells, antigen-presenting cells), mesenchymal stromal cells, adipose cells, nerve, muscle, vascular and endothelial cells, and induced pluripotent stem cells. Elsevier is a global information analytics company that helps institutions and professionals progress science, advance healthcare and improve performance for the benefit of humanity. Elsevier provides digital solutions and tools in the areas of strategic research management, R&D performance, clinical decision support, and professional education; including ScienceDirect, Scopus, ClinicalKey and Sherpath. Elsevier publishes over 2,500 digitized journals, including The Lancet and Cell, more than 35,000 e-book titles and many iconic reference works, including Gray's Anatomy. Elsevier is part of RELX Group, a global provider of information and analytics for professionals and business customers across industries. http://www.
Singh P.S.,Indian Central Salt and Marine Chemicals Research Institute |
Singh P.S.,Academy of Scientific |
Chaudhri S.G.,Indian Central Salt and Marine Chemicals Research Institute |
Kansara A.M.,Indian Central Salt and Marine Chemicals Research Institute |
And 5 more authors.
Bulletin of Materials Science | Year: 2015
A simple preparation of mesostructured cetyltrimethylammonium bromide (CTAB)-silica membrane is reported. It effectively desalinates seawater to pure water through pervaporation separation process. Themembrane thickness was of nanometer-length-scale obtained by deposition of CTAB-silica colloids on porous polysulfone support. Scanning electron microscopy (SEM), atomic force microscopy (AFM) and transmission electron microscopy (TEM) studies were performed to characterize the membrane while the structure of the colloids in coating solution was probed by small-angle neutron scattering (SANS). The prepared membranes exhibited excellent salt rejection efficiency of 99.9% in desalination of synthetic seawater of 40,000 ppm NaCl by pervaporation at 25°C. The pure water flux was in the range of 1-2.6 kg m-2 h depending upon the membrane configuration and thickness. The flux could be greatly enhanced by operating the process at higher temperatures of 40-80°C but it was at the cost of decreased salt-rejection efficiency. The initial rejection efficiency and flux of the membrane was found to be restored upon cooling the membrane back to room temperature.
Chejara D.R.,Indian Central Salt and Marine Chemicals Research Institute |
Chejara D.R.,Academy of Scientific |
Kondaveeti S.,Indian Central Salt and Marine Chemicals Research Institute |
Prasad K.,Indian Central Salt and Marine Chemicals Research Institute |
And 3 more authors.
RSC Advances | Year: 2013
Sodium alginate (Na-Alg) reacted with 1-naphthylamine in the presence of 1-ethyl-3-[3-(dimethylamino)propyl]-carbodiimide hydrochloride (EDC·HCl) affording an amide derivative capable of forming soft hydrogel at a concentration of 4% w/v. The latter upon gentle stirring turned into a viscous sol, which assumed the original gel structure upon standing at room temperature in a reversible process. Such thixotropic materials have the potential to be used in biomedical applications and as sensors. © 2013 The Royal Society of Chemistry.
Chudasama N.A.,Indian Central Salt and Marine Chemicals Research Institute |
Siddhanta A.K.,Indian Central Salt and Marine Chemicals Research Institute |
Siddhanta A.K.,Academy of Scientific
Carbohydrate Research | Year: 2015
In a facile synthesis agarose was amphoterically functionalized to afford nano-sized agarose amino acids, aminoagarose succinate half-esters (AAE) containing one pendant carboxyl group. Nano-sized AAEs (<10nm; DLS) were characterized and they had three various degrees of substitution [overall DSs 0.88, 0.89 and 0.96], both the amino and half-ester groups were placed on C-6 positions of the 1,3 beta-d-galactopyranose moieties of agarose backbone (13C NMR). AAEs performed like large protein molecules exhibiting pH-responsive structural variations (optical rotatory dispersion), presenting a mixed solubility pattern like random coil (soluble) and aggregate (precipitation) formations. Circular dichroism studies showed their pH-dependent associative interactions with bovine serum albumin, which indicated complexation at acidic and basic pHs, and decomplexation at pH6.8 with AAE (DS 0.96). Thus, these nano-sized AAE based systems may be of potential utility in the domains demanding the merits of preferential protein bindings e.g. pH-responsive cationic/anionic drug carrier, separations or chiral sensing applications. © 2015 Elsevier Ltd. All rights reserved.
Dwivedi V.,CSIR - Central Electrochemical Research Institute |
Hari Babu M.,CSIR - Central Electrochemical Research Institute |
Kant R.,CSIR - Central Electrochemical Research Institute |
Sridhar Reddy M.,CSIR - Central Electrochemical Research Institute |
Sridhar Reddy M.,Academy of Scientific
Chemical Communications | Year: 2015
A highly general palladium catalysed regioselective hydroalkynylation of ynamides for versatile enamide building blocks with an alkyne tether is achieved with an N-substitution dependent stereoselectivity switch under very mild reaction conditions. © 2015 The Royal Society of Chemistry.
Hussain N.,CSIR - Central Electrochemical Research Institute |
Hussain N.,Academy of Scientific |
Borah A.,Academy of Scientific |
Borah A.,CSIR - Central Electrochemical Research Institute |
And 9 more authors.
New Journal of Chemistry | Year: 2015
A new strategy for in situ synthesis of palladium nanoparticles (Pd NPs) decorated on reduced graphene oxide (rGO) nanosheets with controlled size and shape is reported. This strategy was designed as three processes in one pot, namely, (a) reduction of graphene oxide, (b) formation of Pd NPs on the rGO nanosheets and (c) simultaneous reduction of olefin. In this synthesis process, a hydrogen atmosphere was used to develop the Pd NPs-rGO nanocatalyst, which is reusable and easily separable. The influence of the size and morphology of the Pd-rGO-H2 catalyst on the catalytic activity in the Suzuki cross-coupling reaction was investigated by comparing with other catalysts, Pd-rGO-As and Pd-rGO-Gl, and they were synthesized by different reducing agents, ascorbic acid and glucose, respectively. The catalysts were characterized by electron microscopy (HRTEM, SEM), FT-IR, XRD and XPS. The Pd-rGO-H2 catalyst was found to possess excellent catalytic activity and recyclability in the Suzuki cross-coupling reaction under mild reaction conditions. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2015.
Yadav M.,Indian Institute of Integrative Medicine |
Yadav M.,Jammu University |
Dara S.,Indian Institute of Integrative Medicine |
Dara S.,Academy of Scientific |
And 10 more authors.
European Journal of Organic Chemistry | Year: 2015
Herein, we report a MnIII-mediated regioselective method for the direct C-H phosphonation of imidazo[1,2-a]pyridines by using dialkyl phosphites. 3-Phosphonated imidazo[1,2-a]pyridines are synthesized in good to excellent yields under the optimized reaction conditions. The present method is also applicable to the functionalization of related heteroarenes, and unlike previously reported methods, the present strategy works well with (NH)-heteroarenes. Regioselective synthesis of phosphonylated heteroarenes: A mild, direct, and regioselective C-H phosphonation of imidazo[1,2-a]pyridines and related heteroarenes has been developed. Unlike those previously reported, the present method also works with (NH)-heteroarenes. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Pasupuleti S.B.,Flemish Institute for Technological Research |
Pasupuleti S.B.,Indian Institute of Chemical Technology |
Pasupuleti S.B.,Academy of Scientific |
Srikanth S.,Flemish Institute for Technological Research |
And 2 more authors.
International Journal of Hydrogen Energy | Year: 2015
Three microbial fuel cells (MFC) with dual gas diffusion cathode design were operated individually in different operation modes, viz., batch (MFC-BM), semi-continuous (MFC-SCM) and continuous (MFC-CM), using dark fermentation effluent (DFE). MFC-BM depicted lower power density (PD, 1.31 ± 1.75 mW/m2) due to the electron losses and mass transfer limitations, while, MFC-SCM (19.06 ± 2.01 mW/m2) and MFC-CM (15.53 ± 2.51 mW/m2) depicted higher PD. Though MFC-SCM showed higher power output, the energy conversion efficiency (ECE) was higher during MFC-CM (9.85 ± 1.02%) operation over MFC-BM and MFC-SCM operations. Henceforth, the stacking approach was carried out in continuous mode operation using DFE which showed a very good power output along with treatment efficiency. Stack mode operation was carried out at decreasing external loads to increase the overall power output as well as the electron delivering ability of the biocatalyst. Stack MFC depicted its maximum PD (3163 mW/m3; 19.79 mW/m2), across 2 kω of external resistance (Rex) along with the treatment efficiency of 80 ± 2%. Further decrement in Rex to 1 kω has resulted in lower and unstable PD, due to the inability of the biocatalyst to meet the electron requirement by the circuit. A detailed understanding of the stack MFC was made in terms of electrogenesis, electron discharge, coulombic and energy conversion efficiencies as well as the bioprocess parameters. © 2015 Hydrogen Energy Publications, LLC.
Sayem Alam M.,CSIR - Central Leather Research Institute |
Sayem Alam M.,Academy of Scientific |
Mandal A.B.,CSIR - Central Leather Research Institute
Journal of Molecular Liquids | Year: 2015
In this investigation, we have studied the micellization of non-ionic surfactant, Triton X-114 (by surface tension measurement) and cationic gemini surfactant, pentanediyl-1,5-bis(dimethylcetylammonium bromide) (16-5-16) by surface tension, conductivity and dye solubilization methods and the clouding phenomena of mixed surfactant (non-ionic Triton X-114 + cationic gemini 16-5-16) system in aqueous solution. The critical micelle concentration (CMC) of Triton X-114 and 16-5-16 were measured and their surface properties and thermodynamics were evaluated. In aqueous solution, non-ionic surfactant, Triton X-114 undergoes phase separation or cloud point (CP). Herein, we also report the influence of additives (e.g., electrolytes, sugars, amino acids, etc.) on the CP of Triton X-114 in aqueous solutions. The CP showed a concentration dependent variation in the absence of any added compound (additives). With the addition of additives, the CP values were found to decrease and increase. It is found that the CP of pure Triton X-114 is concentration dependent; and the presence of gemini surfactant (16-5-16) increases the CP. However, all additives in the presence of the gemini surfactant (i.e., Triton X-114 + 16-5-16 system) decrease the CP. The results are discussed by taking into consideration the nature of the additives. The thermodynamic parameters are also evaluated at CP. © 2015 Elsevier B.V. All rights reserved.