Stem cell based therapies offer significant potential for the field of regenerative medicine. However, much remains to be understood regarding the in vivo kinetics of transplanted cells. A non-invasive method to repetitively monitor transplanted stem cells in vivo would allow investigators to directly monitor stem cell transplants and identify successful or unsuccessful engraftment outcomes. A wide range of stem cells continues to be investigated for countless applications. This protocol focuses on 3 different stem cell populations: human embryonic kidney 293 (HEK293) cells, human mesenchymal stem cells (hMSC) and induced pluripotent stem (iPS) cells. HEK 293 cells are derived from human embryonic kidney cells grown in culture with sheared adenovirus 5 DNA. These cells are widely used in research because they are easily cultured, grow quickly and are easily transfected. hMSCs are found in adult marrow. These cells can be replicated as undifferentiated cells while maintaining multipotency or the potential to differentiate into a limited number of cell fates. hMSCs can differentiate to lineages of mesenchymal tissues, including osteoblasts, adipocytes, chondrocytes, tendon, muscle, and marrow stroma. iPS cells are genetically reprogrammed adult cells that have been modified to express genes and factors similar to defining properties of embryonic stem cells. These cells are pluripotent meaning they have the capacity to differentiate into all cell lineages. Both hMSCs and iPS cells have demonstrated tissue regenerative capacity in-vivo. Magnetic resonance (MR) imaging together with the use of superparamagnetic iron oxide (SPIO) nanoparticle cell labels have proven effective for in vivo tracking of stem cells due to the near microscopic anatomical resolution, a longer blood half-life that permits longitudinal imaging and the high sensitivity for cell detection provided by MR imaging of SPIO nanoparticles. In addition, MR imaging with the use of SPIOs is clinically translatable. SPIOs are composed of an iron oxide core with a dextran, carboxydextran or starch surface coat that serves to contain the bioreactive iron core from plasma components. These agents create local magnetic field inhomogeneities that lead to a decreased signal on T2-weighted MR images. Unfortunately, SPIOs are no longer being manufactured. Second generation, ultrasmall SPIOs (USPIO), however, offer a viable alternative. Ferumoxytol (FerahemeTM) is one USPIO composed of a non-stoichiometric magnetite core surrounded by a polyglucose sorbitol carboxymethylether coat. The colloidal, particle size of ferumoxytol is 17-30 nm as determined by light scattering. The molecular weight is 750 kDa, and the relaxivity constant at 2T MRI field is 58.609 mM(-1) sec(-1) strength. Ferumoxytol was recently FDA-approved as an iron supplement for treatment of iron deficiency in patients with renal failure. Our group has applied this agent in an "off label" use for cell labeling applications. Our technique demonstrates efficient labeling of stem cells with ferumoxytol ...

The COVID-19 lockdown has been reported as a “ventilator” for the reinstatement of natural resources across the globe. Hence, the present study attempts to evaluate the impact of COVID-19 lockdown on the water quality of River Gomti across its stretch of ~960 km through the assessment of ‘Water Quality Index’ (WQI). The study also highlights the potential risk of faecal-oral transmission of COVID-19 through intake of river water facing the issue of direct discharge of domestic sewage. A deterioration in the water quality was witnessed at ~69% sampling locations during the lockdown period (May 2020). Interestingly, none of the water samples during the pre-lockdown, lockdown, and post-lockdown periods across the whole stretch belonged to the “excellent” category (WQI<25). The DO levels fell across ~69% and ~88% of the sites during the lockdown and post-lockdown periods, respectively. Moreover, there was an increase in the BOD 5 levels across ~69% and 75% of the sites during lockdown and post-lockdown periods, respectively. These findings indicate that the release of sewage without or with partial treatment is a chief contributor of water pollution in the groundwater fed River Gomti. Thereby, highlighting the possible risk of faecal-oral transmission of the corona virus, and creating a major concern for the residents across its stretch. The urban sprawl and riverfront development in Lucknow city also emerge as potential causes of water quality deterioration in River Gomti, considering that the water quality at five sites within the city was under the “unfit” category regardless of the lockdown situation. Thus, the urgent need of management of domestic sewage release into the river and further research on the potential risk of faecal-oral transmission of COVID-19 have been suggested in the study.

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The aim of the current study was to evaluate the status of heavy metal contamination in River Gomti for Lucknow district. The quantification of the pollution levels in River Gomti over a stretch of ~ 61 km, has been attempted through heavy metal pollution index (HPI). The results suggested that 30% of the total sites fall under the category of 'highly polluted' (HPI > 30), and 60% of the sites are designated under 'critically polluted' category (HPI > 100). Further, it was found that the mean HPI value across the stretch of the study area was 149.29 signifying towards the category of 'critical pollution' (HPI > 100). The principal component analysis results suggest strong positive loadings on arsenic (As) and lead (Pb) similar to the hierarchal cluster analysis (HCA) results which signified towards close association between As and Pb. A 'good' correlation (0.51 < r < 0.89) has been found for As with Pb and Mn. The possibility of anthropogenic intrusion as a cause for heavy metal contamination at all sites is also signified through the results from HCA. Thus, the untreated discharge from the agricultural runoff, sewage system including domestic and industrial wastewater has emerged as a potential cause of heavy metal contamination in the river water.