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Electrophysiological recordings have enabled identification of physiologically distinct yet behaviorally similar states of mammalian sleep. In contrast, sleep in nonmammals has generally been identified behaviorally and therefore regarded as a physiologically uniform state characterized by quiescence of feeding and locomotion, reduced responsiveness, and rapid reversibility. The nematode Caenorhabditis elegans displays sleep-like quiescent behavior under two conditions: developmentally timed quiescence (DTQ) occurs during larval transitions, and stress-induced quiescence (SIQ) occurs in response to exposure to cellular stressors. Behaviorally, DTQ and SIQ appear identical. Here, we use optogenetic manipulations of neuronal and muscular activity, pharmacology, and genetic perturbations to uncover circuit and molecular mechanisms of DTQ and SIQ. We find that locomotion quiescence induced by DTQ- and SIQ-associated neuropeptides occurs via their action on the nervous system, although their neuronal target(s) and/or molecular mechanisms likely differ. Feeding quiescence during DTQ results from a loss of pharyngeal muscle excitability, whereas feeding quiescence during SIQ results from a loss of excitability in the nervous system. Together these results indicate that, as in mammals, quiescence is subserved by different mechanisms during distinct sleep-like states in C. elegans.

Ectopic calcification is associated with various human diseases, including atherosclerosis, cancer, chronic kidney disease, and diabetes mellitus. Although mineral nanoparticles have been detected in calcified blood vessels, the nature and role of these particles in the human body remain unclear. Here we show for the first time that human kidney tissues obtained from end-stage chronic kidney disease or renal cancer patients contain round, multilamellar mineral particles of 50 to 1,500 nm, whereas no particles are observed in healthy controls. The mineral particles are found mainly in the extracellular matrix surrounding the convoluted tubules, collecting ducts and loops of Henle as well as within the cytoplasm of tubule-delineating cells, and consist of polycrystalline calcium phosphate similar to the mineral found in bones and ectopic calcifications. The kidney mineral nanoparticles contain several serum proteins that inhibit ectopic calcification in body fluids, including albumin, fetuin-A, and apolipoprotein A1. Since the mineralo-organic nanoparticles are found not only within calcified deposits but also in areas devoid of microscopic calcifications, our observations indicate that the nanoparticles may represent precursors of calcification and renal stones in humans.

We analyzed global transcriptome changes during synchronized cell division in the green alga Chlamydomonas reinhardtii. The Chlamydomonas cell cycle consists of a long G1 phase, followed by an S/M phase with multiple rapid, alternating rounds of DNA replication and segregation. We found that the S/M period is associated with strong induction of; 2300 genes, many with conserved roles in DNA replication or cell division. Other genes, including many involved in photosynthesis, are reciprocally downregulated in S/M, suggesting a gene expression split correlating with the temporal separation between G1 and S/M. The Chlamydomonas cell cycle is synchronized by light-dark cycles, so in principle, these transcriptional changes could be directly responsive to light or to metabolic cues. Alternatively, cell-cycle-periodic transcription may be directly regulated by cyclin-dependent kinases. To distinguish between these possibilities, we analyzed transcriptional profiles of mutants in the kinases CDKA and CDKB, as well as other mutants with distinct cell cycle blocks. Initial cell-cycle-periodic expression changes are largely CDK independent, but later regulation (induction and repression) is under differential control by CDKA and CDKB. Deviation from the wild-type transcriptional program in diverse cell cycle mutants will be an informative phenotype for further characterization of the Chlamydomonas cell cycle.

Differential cross sections as a function of transverse momentum p(T) are presented for the production of Upsilon(nS) (n = 1, 2, 3) states decaying into a pair of muons. Data corresponding to an integrated luminosity of 4.9 fb(-1) in pp collisions at root s = 7 TeV were collected with the CMS detector at the LHC. The analysis selects events with dimuon rapidity vertical bar y vertical bar < 1.2 and dimuon transverse momentum in the range 10 < p(T) < 100 GeV. The measurements show a transition from an exponential to a power-law behavior at p(T) approximate to 20 GeV for the three Upsilon states. Above that transition, the Upsilon(3S) spectrum is significantly harder than that of the Upsilon(1S). The ratios of the Upsilon(3S) and Upsilon(2S) differential cross sections to the Upsilon(1S) cross section show a rise as p(T)-increases at low p(T), then become flatter at higher p(T). (C) 2015 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V.

Different dendritic cell (DC) subsets co-exist in humans and coordinate the immune response. Having a short life, DCs must be constantly replenished from their progenitors in the bone marrow through hematopoiesis. Identification of a DC-restricted progenitor in mouse has improved our understanding of how DC lineage diverges from myeloid and lymphoid lineages. However, identification of the DC-restricted progenitor in humans has not been possible because a system that simultaneously nurtures differentiation of human DCs, myeloid and lymphoid cells, is lacking. Here we report a cytokine and stromal cell culture that allows evaluation of CD34(+) progenitor potential to all three DC subsets as well as other myeloid and lymphoid cells, at a single cell level. Using this system, we show that human granulocyte macrophage progenitors are heterogeneous and contain restricted progenitors to DCs. (C) 2015 Published by Elsevier B.V.

Background: Non-steroidal anti-inflammatory drugs such as indomethacin are widely used to treat inflammatory diseases and manage pain, fever and inflammation in several conditions, including neuropsychiatric disorders. Although they predominantly function by inhibiting cyclooxygenase (COX) activity, important COX-independent actions also occur. These actions could be responsible for the adverse side effects associated with chronic and/or high dose usage of this popular drug class. Results: We examined gene regulation in the hippocampus after peripheral administration of indomethacin by employing a microarray approach. Secondary confirmation and the brain expression pattern of regulated genes was examined by in situ hybridization and immunohistochemistry. Transglutaminase 2, serum glucocorticoid inducible kinase, Inhibitor of NF-kappa B and vascular endothelial growth factor were among genes that were prominently upregulated, while G-protein coupled receptor 56 and neuropeptide Y were among genes that were downregulated by indomethacin. Co-localization studies using blood vessel markers revealed that transglutaminase 2 was induced specifically in brain vasculature. Conclusions: The data demonstrate that COX-inhibitors can differentially regulate gene transcription in multiple, functionally distinctly cell types in the brain. The results provide additional insight into the molecular actions of COX-inhibitors and indicate that their effects on vasculature could influence cerebral blood flow mechanisms.

In recent years an extensive effort has been made to elucidate the molecular pathways involved in metabolic signaling in health and disease. Here we show, surprisingly, that metabolic regulation and the heat-shock/stress response are directly linked. Peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1 alpha), a critical transcriptional coactivator of metabolic genes, acts as a direct transcriptional repressor of heat-shock factor 1 (HSF1), a key regulator of the heat-shock/stress response. Our findings reveal that heat-shock protein (HSP) gene expression is suppressed during fasting in mouse liver and in primary hepatocytes dependent on PGC-1 alpha. HSF1 and PGC-1 alpha associate physically and are colocalized on several HSP promoters. These observations are extended to several cancer cell lines in which PGC-1 alpha is shown to repress the ability of HSF1 to activate gene-expression programs necessary for cancer survival. Our study reveals a surprising direct link between two major cellular transcriptional networks, highlighting a previously unrecognized facet of the activity of the central metabolic regulator PGC-1 alpha beyond its well-established ability to boost metabolic genes via its interactions with nuclear hormone receptors and nuclear respiratory factors. Our data point to PGC-1 alpha as a critical repressor of HSF1-mediated transcriptional programs, a finding with possible implications both for our understanding of the full scope of metabolically regulated target genes in vivo and, conceivably, for therapeutics.

Hirsutella sinensis mycelium (HSM), the anamorph of Cordyceps sinensis, is a traditional Chinese medicine that has been shown to possess various pharmacological properties. We previously reported that this fungus suppresses interleukin-1 beta and IL-18 secretion by inhibiting both canonical and non-canonical inflammasomes in human macrophages. However, whether HSM may be used to prevent lung fibrosis and the mechanism underlying this activity remain unclear. Our results show that pretreatment with HSM inhibits TGF-beta 1-induced expression of fibronectin and alpha-SMA in lung fibroblasts. HSM also restores superoxide dismutase expression in TGF-beta 1-treated lung fibroblasts and inhibits reactive oxygen species production in lung epithelial cells. Furthermore, HSM pretreatment markedly reduces bleomycin-induced lung injury and fibrosis in mice. Accordingly, HSM reduces inflammatory cell accumulation in bronchoalveolar lavage fluid and proinflammatory cytokines levels in lung tissues. The HSM extract also significantly reduces TGF-beta 1 in lung tissues, and this effect is accompanied by decreased collagen 3 alpha 1 and alpha-SMA levels. Moreover, HSM reduces expression of the NLRP3 inflammasome and P2X(7)R in lung tissues, whereas it enhances expression of superoxide dismutase. These findings suggest that HSM may be used for the treatment of pulmonary inflammation and fibrosis.

We present a measurement of the Z boson differential cross section in rapidity and transverse momentum using a data sample of pp collision events at a centre-of-mass energy root s = 8 TeV, corresponding to an integrated luminosity of 19.7 fb(-1). The Z boson is identified via its decay to a pair of muons. The measurement provides a precision test of quantum chromodynamics over a large region of phase space. In addition, due to the small experimental uncertainties in the measurement the data has the potential to constrain the gluon parton distribution function in the kinematic regime important for Higgs boson production via gluon fusion. The results agree with the next-to-next-to-leading-order predictions computed with the fewz program. The results are also compared to the commonly used leading-order MADGRAPH and next-to-leading-order POWHEG generators. (C) 2015 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license

Geoffrey W. Smith is currently the Managing Director of Mars Ventures. He actually started his studies with a Bachelor of Arts degree and a Doctorate in Law but then, in part by chance and in part by following in his family footsteps, he stepped into the healthcare and biotech field. Since then, he has successfully contributed to the birth of a number of healthcare companies and has also held academic positions at the Icahn School of Medicine at Mount Sinai and at The Rockefeller University in New York, teaching about the interface between science and business. During 2014 he served as Senior Editor on Disease Models & Mechanisms, bringing to the editorial team his valuable experience in drug development and discovery. In this interview, Geoff talks to Ross Cagan, Editor-in-Chief of Disease Models & Mechanisms, about how he developed his incredibly varied career, sharing his views about industry, academia and science publishing, and discussing how academia and industry can fruitfully meet to advance bioscience, train the scientists and stakeholders of the future, and drive the successful discovery of new therapeutics to treat human disease.