47 research outputs found
Trace metal speciation in environmental aquatic samples of Palar river, Mahabalipurm and its adjoining coast
Surface waters from 6 stations of riverine and coastal waters of Palar river, Mahabalipurm were collected. The hydrographic parameters for these samples were determined by conventional techniques. The DPASV technique was used for the determination of various forms of trace metals like Zn, Pb, Cu and Cd. The total dissolved metals were determined after UV-irradiation of the 0.45 μ filtered water samples. The ASV labile metals in the filtered water samples were determined at natural pH. The suspended particulate matter retained on the 0.45 μfilter paper were digested by using strong acids and the same were used for the determination of suspended particulate bound metals. The total dissolved metals were in general high at the riverine stations compared to coastal stations. However, last two stations on the seaside were showing higher values relative to the station close to the mixing zone. It was found that the percentages of ASV labile and non-labile forms varied widely with respect to the season at different stations. The particulate Zn, Pb and Cu were showing higher values in the monsoon season in riverine waters and in the summer/pre-monsoon for coastal waters. The higher values of the metals in the riverine side and last two stations on the seaside indicate trace metal pollution in the transect
Stem Cell Therapy with Overexpressed VEGF and PDGF Genes Improves Cardiac Function in a Rat Infarct Model
Therapeutic potential was evaluated in a rat model of myocardial infarction using nanofiber-expanded human cord blood derived hematopoietic stem cells (CD133+/CD34+) genetically modified with VEGF plus PDGF genes (VIP).Myocardial function was monitored every two weeks up to six weeks after therapy. Echocardiography revealed time dependent improvement of left ventricular function evaluated by M-mode, fractional shortening, anterior wall tissue velocity, wall motion score index, strain and strain rate in animals treated with VEGF plus PDGF overexpressed stem cells (VIP) compared to nanofiber expanded cells (Exp), freshly isolated cells (FCB) or media control (Media). Improvement observed was as follows: VIP>Exp> FCB>media. Similar trend was noticed in the exercise capacity of rats on a treadmill. These findings correlated with significantly increased neovascularization in ischemic tissue and markedly reduced infarct area in animals in the VIP group. Stem cells in addition to their usual homing sites such as lung, spleen, bone marrow and liver, also migrated to sites of myocardial ischemia. The improvement of cardiac function correlated with expression of heart tissue connexin 43, a gap junctional protein, and heart tissue angiogenesis related protein molecules like VEGF, pNOS3, NOS2 and GSK3. There was no evidence of upregulation in the molecules of oncogenic potential in genetically modified or other stem cell therapy groups.Regenerative therapy using nanofiber-expanded hematopoietic stem cells with overexpression of VEGF and PDGF has a favorable impact on the improvement of rat myocardial function accompanied by upregulation of tissue connexin 43 and pro-angiogenic molecules after infarction