Simian virus 40 (SV40) growth on rhesus kidney cells and on the T-22 line of SV40-transformed green monkey kidney (GMK) cells is largely limited by the low plating efficiency of SV40 on these cells. In addition, a fraction of the rhesus kidney and T-22 cells are resistant to infection by SV40. Nevertheless, 72-h viral yields per infected rhesus kidney and T-22 cell are nearly equivalent to that obtained on normal GMK cells and are independent of the multiplicity of infection. Despite the production of high viral yields, infected rhesus kidney and T-22 cells are killed slowly by SV40. Monolayers of these cells are also refractory to plaque formation by SV40. SV40 induces the release of lysosomal N-acetyl-,8glucosaminidase into the cytoplasmic fractions of rhesus kidney and T-22 cells to an extent equal to that observed during infection of rapidly killed normal GMK cells. In contrast, damage to the plasma membrane, as indicated by the release of the cellular enzymes lactic dehydrogenase and glutamic oxaloacetic transaminase into the overlay media, occurred to a much greater extent in the normal GMK cells than in the rhesus kidney or T-22 cells. Neither a lysosomal hydrolase mechanism nor viral release appear to be responsible for this phenomenon. The different rates and extents ofthe SV40 cytocidal process on these cells do not result from the differences in the viral plating efficiency on them.

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In this model, losartan did not improve survival compared to placebo and quinapril and, if anything, increased mortality. Our results suggest that AT1 receptor antagonists and ACE inhibitors are not necessarily equivalent or interchangeable in terms of their effects on cardiac hypertrophy and survival in selected progressive heart failure models.

Reproductive tracts were collected on the eastern coast of Canada from adult female grey seals (Halichoerus grypus) during gestation and postparturition, and from adult female harp seals (Phoca groenlandica) during delayed implantation and postparturition. Reproductive tracts were fixed in 10% buffered formalin for light microscopy. The placental site and adjacent tissue were preserved in 2% glutaraldehyde – 1% paraformaldehyde for scanning electron microscopy. During the delay of blastocyst implantation, the endometria of the gravid and nongravid uterine horns were similar in microscopic appearance. During gestation, maternal septa were often surrounded by maternal epithelium deep into the placental labyrinth except distally, where the maternal cells were replaced by syncytium. Marginal hematomas increased in size and complexity throughout placentation. Following parturition, uterine regression occurred earlier in harp seals (10 days postpartum) than in grey seals (21–25 days postpartum). Postpartum changes were most pronounced in the placental site where the blood vessels underwent extensive reorganization. In some specimens, the extensively vascularized placental site of the previous pregnancy was still apparent 12 months later. Epithelial replacement in the uterus was complete in grey seals 21–25 days postpartum and sooner in harp seals. Cervical and vaginal stratification occurred in both phocids following parturition and increased towards estrus. A recently ovulated grey seal was obtained between 21 and 25 days postpartum. The vaginal stratification and the presence of sperm in their uterine horns indicated that grey seals began estrus about 12–17 days postpartum. In harp seals, estrus appeared to occur towards the end of the lactational period, about 10–12 days postpartum.

BACKGROUND Endocrine disruptors (EDs) contribute to the endocrine disrupting potential of urban wastewater because most wastewater treatment plants only partially remove these compounds. Many EDs are present at very low concentrations in wastewater, which explains why most wastewater treatment plants can only partially remove them. The development of a two‐phase partitioning bioreactor (TPPB) could represent an alternative for the extraction of these compounds from water prior to their biodegradation. This study assesses the potential of using the polymer Hytrel used in TPPBs, to extract and concentrate estrone, estradiol, estriol, ethynylestradiol, nonylphenol and bisphenol A from aqueous solutions. RESULTS Hytrel demonstrated high capacity absorption for all these EDs. The Hytrel/water partition coefficient for the six EDs was determined. Finally, the capacity of Hytrel to extract a high proportion of these EDs from ED‐spiked, treated wastewater was demonstrated. CONCLUSION Our results showed that Hytrel has the potential to be used as an effective water‐immiscible phase in the development of a TPPB for the extraction and biodegradation of EDs. Copyright © 2012 Society of Chemical Industry

Naturally occurring and synthetic estrogens and other molecules from industrial sources strongly contribute to the endocrine disruption of urban wastewater. Because of the presence of these molecules in low but effective concentrations in wastewaters, these endocrine disruptors (EDs) are only partially removed after most wastewater treatments, reflecting the presence of these molecules in rivers in urban areas. The development of a two-phase partitioning bioreactor (TPPB) might be an effective strategy for the removal of EDs from wastewater plant effluents. Here, we describe the establishment of three ED-degrading microbial enrichment cultures adapted to a solid-liquid two-phase partitioning system using Hytrel as the immiscible water phase and loaded with estrone, estradiol, estriol, ethynylestradiol, nonylphenol, and bisphenol A. All molecules except ethynylestradiol were degraded in the enrichment cultures. The bacterial composition of the three enrichment cultures was determined using 16S rRNA gene sequencing and showed sequences affiliated with bacteria associated with the degradation of these compounds, such as Sphingomonadales. One Rhodococcus isolate capable of degrading estrone, estradiol, and estriol was isolated from one enrichment culture. These results highlight the great potential for the development of TPPB for the degradation of highly diluted EDs in water effluents.

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Current chemotherapy of pediatric T cell acute lymphoblastic leukemia (T-ALL) efficiently reduces the tumor mass with, however, undesirable long term consequences and remains ineffective in adolescent and adult T-ALL. Furthermore, relapse can be caused by pre-leukemic stem cells (pre-LSCs) that were spared by current protocols and evolved to malignancy. A distinctive characteristic of pre-LSCs is their critical dependence on interactions with the microenvironment for survival, which guided our strategy to target pre-LSCs using niche-based screening assays. Using transgenic mouse models that closely reproduce the human disease, we showed that the SCL/TAL1 and LMO1 oncogenic transcription factors establish a pre-leukemic state by reprogramming normal pro-T cells into aberrantly self-renewing pre-LSCs (Gerby et al. PloS Genetics, 2014). We now provide direct evidence that pre-LSCs are much less chemosensitive than leukemic blasts to current drugs, due to a distinctive lower proliferative state as assessed by real-time imaging in a competitive assay. We therefore designed a robust protocol for high-throughput screening (HTS) of compounds targeting primary pre-LSCs that are maintained on stromal cells engineered for optimal NOTCH1 activation to mimick the thymic microenvironement. The multiparametric readout takes into account the intrinsic complexity of primary cells to specifically monitor pre-LSCs. We screened a targeted library of 1904 compounds and identified UM0119979 that disrupts both cell autonomous and non-cell autonomous pathways: UM0119979 abrogates pre-LSC viability and self-renewal activity in vivo by specifically inhibiting the translation of MYC, a downstream effector of NOTCH1, and preventing SCL/TAL1 activity. In contrast, normal hematopoietic stem/progenitor cells remain functional. Moreover, in vivo administration of UM0119979 efficiently reduced the leukemia propagating activity of primary human T-ALL samples in xenografted mice. Finally, in addition to SCL-LMO-induced T-ALL, our results reveal a novel possibility of therapeutic intervention in MYC-dependent hematologic malignancies. In summary, our screening assay, built on the genetic dependencies of pre-LSCs, revealed their vulnerabilities to compounds that inhibit both the primary oncogenes and non-cell autonomous pathways triggered by the microenvironment. The results illustrate how recapitulating tissue-like properties of primary cells in high throughput screening is a promising avenue for innovation in cancer chemotherapy. Disclosures No relevant conflicts of interest to declare.