Identification of genomic biomarkers for anthracycline-induced cardiotoxicity in human iPSC-derived cardiomyocytes: an in vitro repeated exposure toxicity approach for safety assessment.

The currently available techniques for the safety evaluation of candidate drugs are usually cost-intensive and time-consuming and are often insufficient to predict human relevant cardiotoxicity. The purpose of this study was to develop an in vitro repeated exposure toxicity methodology allowing the identification of predictive genomics biomarkers of functional relevance for drug-induced cardiotoxicity in human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). The hiPSC-CMs were incubated with 156 nM doxorubicin, which is a well-characterized cardiotoxicant, for 2 or 6 days followed by washout of the test compound and further incubation in compound-free culture medium until day 14 after the onset of exposure. An xCELLigence Real-Time Cell Analyser was used to monitor doxorubicin-induced cytotoxicity while also monitoring functional alterations of cardiomyocytes by counting of the beating frequency of cardiomyocytes. Unlike single exposure, repeated doxorubicin exposure resulted in long-term arrhythmic beating in hiPSC-CMs accompanied by significant cytotoxicity. Global gene expression changes were studied using microarrays and bioinformatics tools. Analysis of the transcriptomic data revealed early expression signatures of genes involved in formation of sarcomeric structures, regulation of ion homeostasis and induction of apoptosis. Eighty-four significantly deregulated genes related to cardiac functions, stress and apoptosis were validated using real-time PCR. The expression of the 84 genes was further studied by real-time PCR in hiPSC-CMs incubated with daunorubicin and mitoxantrone, further anthracycline family members that are also known to induce cardiotoxicity. A panel of 35 genes was deregulated by all three anthracycline family members and can therefore be expected to predict the cardiotoxicity of compounds acting by similar mechanisms as doxorubicin, daunorubicin or mitoxantrone. The identified gene panel can be applied in the safety assessment of novel drug candidates as well as available therapeutics to identify compounds that may cause cardiotoxicity

Lactation Defect in a Widely Used MMTV-Cre Transgenic Line of Mice

MMTV-Cre mouse lines have played important roles in our understanding about the functions of numerous genes in mouse mammary epithelial cells during mammary gland development and tumorigenesis. However, numerous studies have not included MMTV-Cre mice as controls, and many investigators have not indicated which of the different MMTV-Cre founder lines were used in their studies. Here, we describe a lactation defect that severely limits the use of one of the most commonly used MMTV-Cre founder lines.To explore the role of protein tyrosine phosphatase Shp1 in mammary gland development, mice bearing the floxed Shp1 gene were crossed with MMTV-Cre mice and mammary gland development was examined by histological and biochemical techniques, while lactation competency was assessed by monitoring pup growth. Surprisingly, both the Shp1fl/+;MMTV-Cre and MMTV-Cre female mice displayed a severe lactation defect when compared to the Shp1 fl/+ control mice. Histological and biochemical analyses reveal that female mice expressing the MMTV-Cre transgene, either alone or in combination with floxed genes, exhibit defects in lobuloalveolar expansion, presence of large cytoplasmic lipid droplets in luminal alveolar epithelial cells postpartum, and precocious induction of involution. Using a PCR-based genotyping method, the three different founder lines can be distinguished, and we determined that the MMTV-Cre line A, the most widely used MMTV-Cre founder line, exhibits a profound lactation defect that limits its use in studies on mammary gland development.The identification of a lactation defect in the MMTV-Cre line A mice indicates that investigators must use MMTV-Cre alone mice as control in studies that utilize Cre recombinase to excise genes of interest from mammary epithelial cells. Our results also suggest that previous results obtained in studies using the MMTV-Cre line A line should be re-evaluated if the controls did not include mice expressing only Cre recombinase

Studies on sorption properties of pathogens on natural materials

Presence of pathogens in high numbers in waste water is a cause of concern. Techno economic feasibility has restricted the conventional and non conventional treatment approaches for pathogen removal. Despite prolific use, carbon adsorption technology remains an expensive treatment process. The present study investigates the use of rice husk (RH), sawdust (SD), groundnut shells (GS) as natural agro-residues and partially weathered deccan trap basalt (PWDTB) for their sorption capacities and desorption pattern for two indicator organisms viz. Escherichia coli K12 and Staphylococcus aureus. Sorption experiments were carded out at flow-rate of 1.5 bed volumes per hour (bv hr(-1)) for cell suspension volume of 4, 8,16 and 32 bed volumes. PWDTB have shown high sorption coefficient and log removal for E coli K12 whereas GS have shown high sorption coefficient and log removal for S. aureus. PWDTB have shown maximum desorption constant and log retention for E. coli K12 whereas GS have shown maximum desorption constant and log retention for S. aureus during desorption experiment. Retention pattern suggest that adsorption is partially irreversible for almost all the materials used. It suggest that PWDTB in combination with RH and/GS could help in removal of pathogens from waste water

Pathogen removal from municipal wastewater in constructed soil filter

In this work, a Constructed Soil Filter (CSF) system has been configured for the treatment of wastewater wherein we recreate a soil ecosystem for water purification. Purification capacity and seasonal variability of three such CSF facilities for indicator organisms as well as enteric pathogens monitored over 9–17 months are presented. Indicator organisms include total coliform, fecal coliform, fecal streptococci, heterotrophic plate count, Enterococcus fecalis, actinomycetes, and coliphage. Enteric pathogens include Escherichia coli 25922, E. coli O157:H7, Klebsiella pneumoniae, Pseudomonas aeruginosa, Clostridium perfringens, Staphylococcus aureus, Proteus mirabilis. All three sites show bacterial removal rate constant (kd) in the range of 0.4–1.3 h−1 which is very high in comparison to the reported values from field as well as lab studies. Log removal for pathogens is typically 2–3 log orders. However, by extended recycling up to 5 log orders removal could be achieved. Among the three sites, kd values were in the order of site II > site I > site III, which is also the order of their commissioning, suggesting that these system matures with age. Low hydraulic retention time (0.5–2.0 h), no pretreatment, high removal efficiency, no mechanical aeration, very low energy requirement, and green ambience are the unique features of CSF.© Elsevie

Municipal wastewater treatment using novel constructed soil filter system

The study gives a new approach for contaminant removal from municipal wastewater using constructed soil filter (CSF) and presents performance of two CSF units located in Mumbai, India. In this system, natural weathered rock is formulated which combines sedimentation, infiltration and biochemical processes to remove suspended solids and oxidisable organics and inorganics of the wastewater. Results show elevated dissolved oxygen (DO) levels, removal of COD (136–205 to 38–40 mg l−1) and BOD (80–125 to less than 12 mg l−1) suspended solids from 135–203 to 13–18 mg l−1 and turbidity from 84–124 to 8–11 NTU, bacterial removal of 2.4–3.1 log order for Total coliform and Fecal coliform from site I which is almost 8 years old facility, and site II which is 3 years old. Estimated hydraulic retention time of 0.5–1.0 h, hydraulic loading of 0.036–0.047 m3 m−2 h−1, no pretreatment, high DO levels in the effluent, no bio-sludge production, no mechanical aeration, low energy requirement (0.04 kW h m−3) and green aesthetic ambience are its unique features.© Elsevie