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881.
Tanja Wilke Wilko H. Ahlrichs Olaf R.P. Bininda-Emonds 《Journal of Natural History》2019,53(7-8):413-423
The morphology of soft-bodied rotifers, including those of Synchaeta spp, can be strongly affected by preparation artefacts including contraction and deformation. The long-standing, valid species Synchaeta monopus is known exclusively from ethanol- or formaldehyde-preserved material and no live specimens of it have ever been described. Although this alone is cause for concern, we could also reproduce unique characteristics diagnostic for this species (e.g. the swollen body and the rudimental foot) by subjecting specimens of Synchaeta pectinata to the preservation conditions under which it was first described. This proxy experiment and comparisons to other Synchaeta species indicate that literature occurrences of S. monopus likely represent preserved and deformed specimens of Synchaeta cecilia or other marine species of Synchaeta, thereby highlighting the importance of thorough morphological investigations of the habitus using live specimens and of features that are unaffected by preservation (e.g. the trophi). We therefore recommend that S. monopus be listed as a species inquirenda until topotypes are examined. Furthermore, in ecological studies including rotifers, where the examination of preserved material is often unavoidable, we stress that light-microscopical images of the habitus and trophi of the specimens minimally be included to facilitate independent verification of the species assignments. 相似文献
882.
This paper primarily aims to test a Pleistocene refuge-type scenario, as previously proposed for the gonyleptid Geraeocormobius sylvarum, a semi-deciduous forests dweller in subtropical Argentina, Brazil and Paraguay. Palaeodistributional models of this species were built using MaxEnt for two Last Glacial Maximum (LGM = 21,000 years ago) simulations – Community Climate System Model (CCSM) and Model for Interdisciplinary Research on Climate (MIROC) – and for 6000 years ago (?6k = HCO, the Holocene climatic optimum). Both LGM models retrieved a fragmented pattern. For CCSM, range was split into multiple, scattered fragments. MIROC resulted in very few patches, with a decided range reduction because of a strong humidity drop. Models for ?6k recovered a moderate range expansion. No past connection between the core area and the yungas was predicted. Analysis of variables importance showed that two precipitation predictors (bc18, precipitation warmest quarter; bc14, precipitation driest month) and two temperature predictors (bc7, temperature annual range; bc9, mean temperature driest quarter) scored as the most influencing overall. The Limiting Factor analysis recognized them as limiting too, in different parts of the species range. LGM palaeomodels of G. sylvarum are compatible with the refuge hypothesis invoked in previous molecular analyses, to explain the high genetic diversity found in the core area. Additionally, the results reinforced the hypothesis of the recent anthropogenic origin of the yungas disjunct populations. 相似文献
883.
Neveen S. Gadallah Ahmed M. Soliman Hathal M. Al Dhafer 《Journal of Natural History》2017,51(3-4):97-113
The present study summarizes additions to the known fauna of Eucharitidae of Saudi Arabia. Cherianella arabica Gadallah &; Soliman sp. nov. and the male of previously known female Eucharis (Psilogastrellus) albipennis Bou?ek, 1956 are described and illustrated. Three new records are also added to the fauna of Saudi Arabia: Eucharis (Eucharisca) intermedia Ruschka, 1924, Eucharis (Psilogastrellus) acuminata Ruschka, 1924 and Eucharis (Psilogastrellus) punctata Förster, 1859.http:/zoobank.org/urn:lsid:zoobank.org:pub:F1B1C493-AA83-4696-AF8B-3B3F62C09B41 相似文献
884.
S. Lecompte M. Abou-Samra R. Boursereau L. Noel S. M. Brichard 《Cellular and molecular life sciences : CMLS》2017,74(13):2487-2501
Background
Persistent inflammation exacerbates the progression of Duchenne muscular dystrophy (DMD). The hormone, adiponectin (ApN), which is decreased in the metabolic syndrome, exhibits anti-inflammatory properties on skeletal muscle and alleviates the dystrophic phenotype of mdx mice. Here, we investigate whether ApN retains its anti-inflammatory action in myotubes obtained from DMD patients. We unravel the underlying mechanisms by studying the secretome and the early events of ApN.Methods
Primary cultures of myotubes from DMD and control patients were treated or not by ApN after an inflammatory challenge. Myokines secreted in medium were identified by cytokine antibody-arrays and ELISAs. The early events of ApN signaling were assessed by abrogating selected genes.Results
ApN retained its anti-inflammatory properties in both dystrophic and control myotubes. Profiling of secretory products revealed that ApN downregulated the secretion of two pro-inflammatory factors (TNFα and IL-17A), one soluble receptor (sTNFRII), and one chemokine (CCL28) in DMD myotubes, while upregulating IL-6 that exerts some anti-inflammatory effects. These changes were explained by pretranslational mechanisms. Earlier events of the ApN cascade involved AdipoR1, the main receptor for muscle, and the AMPK-SIRT1-PGC-1α axis leading, besides alteration of the myokine profile, to the upregulation of utrophin A (a dystrophin analog).Conclusion
ApN retains its beneficial properties in dystrophic muscles by activating the AdipoR1-AMPK-SIRT1-PGC-1α pathway, thereby inducing a shift in the secretion of downstream myokines toward a less inflammatory profile while upregulating utrophin. ApN, the early events of the cascade and downstream myokines may be therapeutic targets for the management of DMD.885.
Duyilemi C. Ajonijebu Oualid Abboussi Vivienne A. Russell Musa V. Mabandla William M. U. Daniels 《Cellular and molecular life sciences : CMLS》2017,74(15):2735-2747
The detrimental effects of drug abuse are apparently not limited to individuals but may also impact the vulnerability of their progenies to develop addictive behaviours. Epigenetic signatures, early life experience and environmental factors, converge to influence gene expression patterns in addiction phenotypes and consequently may serve as mediators of behavioural trait transmission between generations. The majority of studies investigating the role of epigenetics in addiction do not consider the influence of social interactions. This shortcoming in current experimental approaches necessitates developing social models that reflect the addictive behaviour in a free-living social environment. Furthermore, this review also reports on the advancement of interventions for drug addiction and takes into account the emerging roles of histone deacetylase (HDAC) inhibitors in the etiology of drug addiction and that HDAC may be a potential therapeutic target at nucleosomal level to improve treatment outcomes. 相似文献
886.
Trinidad Montero-Melendez Rachel A. E. Forfar Jennifer M. Cook Jeffrey C. Jerman Debra L. Taylor Mauro Perretti 《Cellular and molecular life sciences : CMLS》2017,74(7):1335-1345
The efficiency of drug research and development has paradoxically declined over the last decades despite major scientific and technological advances, promoting new cost-effective strategies such as drug repositioning by systematic screening for new actions of known drugs. Here, we performed a screening for positive allosteric modulators (PAMs) at melanocortin (MC) receptors. The non-steroidal anti-inflammatory drug fenoprofen, but not the similar compound ibuprofen, presented PAM activity at MC3, MC4, and MC5 receptors. In a model of inflammatory arthritis, fenoprofen afforded potent inhibition while ibuprofen was nearly inactive. Fenoprofen presented anti-arthritic actions on cartilage integrity and synovitis, effects markedly attenuated in Mc3r?/? mice. Fenoprofen displayed pro-resolving properties promoting macrophage phagocytosis and efferocytosis, independently of cyclooxygenase inhibition. In conclusion, combining repositioning with advances in G-protein coupled receptor biology (allosterism) may lead to potential new therapeutics. In addition, MC3 PAMs emerged as a viable approach to the development of innovative therapeutics for joint diseases. 相似文献
887.
E. Giacomelli C. L. Mummery M. Bellin 《Cellular and molecular life sciences : CMLS》2017,74(20):3711-3739
Technical advances in generating and phenotyping cardiomyocytes from human pluripotent stem cells (hPSC-CMs) are now driving their wider acceptance as in vitro models to understand human heart disease and discover therapeutic targets that may lead to new compounds for clinical use. Current literature clearly shows that hPSC-CMs recapitulate many molecular, cellular, and functional aspects of human heart pathophysiology and their responses to cardioactive drugs. Here, we provide a comprehensive overview of hPSC-CMs models that have been described to date and highlight their most recent and remarkable contributions to research on cardiovascular diseases and disorders with cardiac traits. We conclude discussing immediate challenges, limitations, and emerging solutions. 相似文献
888.
G. M. C. Janssen P. Schwertman T. A. T. Wanga R. S. Jahangir Tafrechi P. J. A. van den Broek A. K. Raap 《Cellular and molecular life sciences : CMLS》2009,66(4):721-730
Cytoplasmic translation is under sophisticated control but how cells adapt its rate to constitutive loss of mitochondrial
oxidative phosphorylation is unknown. Here we show that translation is repressed in cells with the pathogenic A3243G mtDNA
mutation or in mtDNA-less ρ0 cells by at least two distinct pathways, one transiently targeting elongation factor eEF-2 and the other initiation factor
eIF-2α constitutively. Under conditions of exponential cell growth and mammalian target of rapamycin (mTOR) activation, eEF-2
becomes transiently phosphorylated by an AMP-activated protein kinase (AMPK)-dependent pathway, especially high in mutant
cells. Independent of AMPK and mTOR, eIF-2α is constitutively phosphorylated in mutant cells, likely a signature of endoplasmic
reticulum (ER)-stress response induced by the loss of oxidative phosphorylation. While the AMPK/eEF-2K/eEF-2 pathway appears
to function in adaptation to physiological fluctuations in ATP levels in the mutant cells, the ER stress signified by constitutive
protein synthesis inhibition through eIF-2α-mediated repression of translation initiation may have pathobiochemical consequences.
Received 29 October 2008; received after revision 11 December 2008; accepted 16 December 2008 相似文献
889.
V. Le Fourn K. Gaplovska-Kysela B. Guhl R. Santimaria C. Zuber J. Roth 《Cellular and molecular life sciences : CMLS》2009,66(8):1434-1445
Little is known about the fate of machinery proteins of the protein quality control and endoplasmic reticulum(ER)-associated
degradation (ERAD). We investigated the degradation of the ERAD component EDEM1, which directs overexpressed misfolded glycoproteins
to degradation. Endogenous EDEM1 was studied since EDEM1 overexpression not only resulted in inappropriate occurrence throughout
the ER but also caused cytotoxic effects. Proteasome inhibitors had no effect on the clearance of endogenous EDEM1 in non-starved
cells. However, EDEM1 could be detected by immunocytochemistry in autophagosomes and biochemically in LC3 immuno-purified
autophagosomes. Furthermore, influencing the lysosome-autophagy pathway by vinblastine or pepstatin A/E64d and inhibiting
autophagosome formation by 3-methyladenine or ATGs short interfering RNA knockdown stabilized EDEM1. Autophagic degradation
involved removal of cytosolic Triton X-100-insoluble deglycosylated EDEM1, but not of EDEM1-containing ER cisternae. Our studies
demonstrate that endogenous EDEM1 in cells not stressed by the expression of a transgenic misfolded protein reaches the cytosol
and is degraded by basal autophagy.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Received 15 January 2009; received after revision 16 February 2009; accepted 17 February 2009
V. Le Fourn, K. Gaplovska-Kysela: These authors equally contributed to this work. 相似文献
890.
A. Beqqali W. van Eldik C. Mummery R. Passier 《Cellular and molecular life sciences : CMLS》2009,66(5):800-813
Studies on identification, derivation and characterization of human stem cells in the last decade have led to high expectations
in the field of regenerative medicine. Although it is clear that for successful stem cell-based therapy several obstacles
have to be overcome, other opportunities lay ahead for the use of human stem cells. A more immediate application would be
the development of human models for cell-type specific differentiation and disease in vitro. Cardiomyocytes can be generated from stem cells, which have been shown to follow similar molecular events of cardiac development
in vivo. Furthermore, several monogenic cardiovascular diseases have been described, for which in vitro models in stem cells could be generated. Here, we will discuss the potential of human embryonic stem cells, cardiac stem
cells and the recently described induced pluripotent stem cells as models for cardiac differentiation and disease.
Received 07 August 2008; received after revision 26 September 2008; accepted 03 October 2008 相似文献