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The immunomodulatory properties of human endometrial mesenchymal stem cells (eMSC) have not been well characterised. Initial studies showed that eMSC modulated the chronic inflammatory response to a non-degradable polyamide/gelatin mesh in a xenogeneic rat skin wound repair model, but the mechanism remains unclear. In this study, we investigated the immunomodulatory effect of eMSC on the macrophage response to polyamide/gelatin composite mesh in an abdominal subcutaneous wound repair model in C57BL6 immunocompetent and NSG (NOD-Scid-IL2Rgamma null ) immunocompromised mice to determine whether responses differed in the absence of an adaptive immune system and NK cells. mCherry lentivirus-labelled eMSC persisted longer in NSG mice, inducing longer term paracrine effects. Inclusion of eMSC in the mesh reduced inflammatory cytokine (Il-1β, Tnfα) secretion, and in C57BL6 mice reduced CCR7 + M1 macrophages surrounding the mesh on day 3 and increased M2 macrophage marker mRNA ( Arg1 , Mrc1, Il10 ) expression at days 3 and 7. In NSG mice, these effects were delayed and only observed at days 7 and 30 in comparison with controls implanted with mesh alone. These results show that the differences in the immune status in the two animals directly affect the survival of xenogeneic eMSC which leads to differences in the short-term and long-term macrophage responses to implanted meshes.

Mitochondrial DNA (mtDNA) copy number is strictly regulated during differentiation so that cells with a high requirement for ATP generated through oxidative phosphorylation have high mtDNA copy number, whereas those with a low requirement have few copies. Using immunoprecipitation of DNA methylation on 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC), which distinguish between de nov o DNA methylation and demethylation, respectively, we set out to determine whether DNA methylation at exon 2 of the human mtDNA-specific polymerase (DNA polymerase gamma A ( POLGA )) regulates cell-specific mtDNA copy number in highly proliferative and terminally differentiated cells. Highly proliferative cancer and pluripotent and multipotent cells possessed low mtDNA copy number and were highly methylated at exon 2 of POLGA in contrast to post-mitotic cells. Unlike neural stem cells, cancer cells were unable to differentiate and remained extensively DNA methylated at exon 2 of POLGA. However, mtDNA depletion of cancer cells reduced DNA methylation at exon 2 of POLGA as they replenished mtDNA to form tumours in mice. Glioblastoma cells treated with the DNA demethylation agent 5-azacytidine over 28 days of astrocyte-induced differentiation demethylated exon 2 of POLGA leading to increased mtDNA copy number and expression of the astrocyte endpoint marker glial fibrillary acidic protein ( GFAP ). However, the demethylation agent vitamin C (VitC) was unable to sustain increased mtDNA copy number and differentiation, as was the case when VitC was withdrawn after short-term treatment. These data demonstrate that DNA demethylation of POLGA is an essential regulator of mtDNA copy number and cellular fate and that cancer cells are only able to modulate DNA methylation of POLGA and mtDNA copy number in the presence of a DNA demethylation agent that inhibits de novo methyltransferase 1 activity.

High-grade glioma (HGG) is an incurable brain cancer. The transcriptomes of cells within HGG tumors are highly heterogeneous. This renders the tumors unresponsive or able to adapt to therapeutics targeted at single pathways, thereby causing treatment failure. To overcome this, we focused on cyclin-dependent kinase 7 (CDK7), a ubiquitously expressed molecule involved in two major drivers of HGG pathogenesis: cell cycle progression and RNA polymerase-II-based transcription. We tested the activity of THZ1, an irreversible CDK7 inhibitor, on patient-derived primary HGG cell lines and ex vivo HGG patient tissue slices, using proliferation assays, microarray analysis, high-resolution respirometry, cell cycle analysis and in vivo tumor orthografts. The cellular processes affected by CDK7 inhibition were analyzed by reverse transcriptase–quantitative PCR, western blot, flow cytometry and immunofluorescence. THZ1 perturbed the transcriptome and disabled CDK activation, leading to cell cycle arrest at G2 and DNA damage. THZ1 halted transcription of the nuclear-encoded mitochondrial ribosomal genes, reducing mitochondrial translation and oxidative respiration. It also inhibited the expression of receptor tyrosine kinases such as epidermal growth factor receptor (EGFR) and platelet-derived growth factor receptor-α (PDGFR-α), reducing signaling flux through the AKT, extracellular-signal-regulated kinase 1/2 (ERK1/2) and signal transducer and activator of transcription 3 (STAT3) downstream pathways. Finally, THZ1 disrupted nucleolar, Cajal body and nuclear speckle formation, resulting in reduced cytosolic translation and malfunction of the spliceosome and thus leading to aberrant mRNA processing. These findings indicate that CDK7 is crucial for gliomagenesis, validate CDK7 as a therapeutic target and provide new insight into the cellular processes that are affected by THZ1 and induce antitumor activity.

The rat connexin40 gap junction channel is permeable to monovalent cations including tetramethylammonium and tetraethylammonium ions. Larger tetraalkyammonium (TAA +) ions beginning with tetrabutylammonium (TBA +) reduced KCl junctional currents disproportionately. Ionic blockade by tetrapentylammonium (TPeA +) and tetrahexylammonium (THxA +) ions were concentration- and voltage-dependent and occurred only when TAA + ions were on the same side as net K + efflux across the junction, indicative of block of the ionic permeation pathway. The voltage-dependent dissociation constants ( K m( V j)) were lower for THxA + than TPeA +, consistent with steric effects within the pore. The K m –V j relationships for TPeA + and THxA + were fit with different reaction rate models for a symmetrical (homotypic) connexin gap junction channel and were described by either a one- or two-site model that assumed each ion traversed the entire V j field. Bilateral addition of TPeA + ions confirmed a common site of interaction within the pore that possessed identical K m( V j) values for cis–trans concentrations of TPeA + ions as indicated by the modeled I–V relations and rapid channel block that precluded unitary current measurements. The TAA + block of K + currents and bilateral TPeA + interactions did not alter V j-gating of Cx40 gap junctions. N-octyl-tributylammonium and -triethylammonium also blocked rCx40 channels with higher affinity and faster kinetics than TBA + or TPeA +, indicative of a hydrophobic site within the pore near the site of block.

Twenty seven babies with severe non-haemolytic hydrops fetalis were born during a 7 1/4 year period (1/1400 total births). Thirteen were live born and admitted to the intensive care nursery, but only three survived. The survivors differed from those live born infants who died in the neonatal period in that the cause of the hydrops was discovered antenatally, their serum concentrations of total protein and albumin were normal, and they had no structural anomaly. A scheme of investigation of the severely hydropic fetus in the antenatal period is outlined and the role of active obstetric management is evaluated.

HIN-200 proteins are interferon (IFN)-inducible proteins that can regulate cell proliferation and differentiation in vitro. Characterization of the lineage and cell type-dependent expression of Ifi202 revealed little or no expression of Ifi202 in the Lin−/c-Kit+ fraction enriched for immature hematopoietic progenitor cells (HPCs) but higher levels in more differentiated Lin−/c-Kit− and Lin+ populations. The highest levels of Ifi202 expression were observed in CD11b+/Gr-1dim immature granulocytes in the bone marrow. In the peripheral blood, Ifi202 was expressed only in the myeloid lineage, with the highest level of expression seen in CD11b+/Gr-1dim immature granulocytes. Constitutive expression of p202 in primary HPCs delayed proliferation of these cells in vitro, caused a reduction in the number and size of myeloid colonies growing on methylcellulose, and affected the ability of the cells to reconstitute irradiated mice but did not significantly affect cell differentiation. Thus, p202 plays a role in regulating the proliferative capacity of hematopoietic cells.

An audible Doppler ultrasound method for detecting human fetal breathing movements in utero has been developed. The frequencies synchronous with fetal breathing movements probably originate from the lung rather than the chest wall. This method is much cheaper and simpler than the ultrasound A-scan method and is suitable for screening large numbers of people.