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121.
Zhen‐Yu Li Yu‐Cheng Gu Dianne Irwin Jacqueline Sheridan John Clough Ping Chen Shu‐Ying Peng Yi‐Ming Yang Yue‐Wei Guo 《化学与生物多样性》2009,6(10):1744-1750
Two new Daphniphyllum alkaloids, macropodumines J and K ( 1 and 2 , resp.), together with six known structurally related alkaloids, 3 – 8 , were isolated from the bark of Daphniphyllum macropodum Miq . The structures of the new compounds 1 and 2 were elucidated on the basis of a comprehensive analysis of their spectroscopic and chemical data. Macropodumine J ( 1 ) contains a CN group which is relatively rare in naturally occurring alkaloids. All isolated compounds were tested for their insecticidal activities against a number of insect species. Daphtenidine C ( 5 ) is the most active compound against Plutella xylostella. This is the first report of insecticidal properties of Daphniphyllum alkaloids. 相似文献
122.
A MicroRNA Cluster miR‐23–24–27 Is Upregulated by Aldosterone in the Distal Kidney Nephron Where it Alters Sodium Transport
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Luigi Montibeller Li Yi Tan Joo Kyung Kim Praveen Paul Jacqueline de Belleroche 《Journal of cellular and molecular medicine》2020,24(11):6055-6069
Amyotrophic lateral sclerosis (ALS) is a disorder that affects motor neurons in motor cortex and spinal cord, and the degeneration of both neuronal populations is a critical feature of the disease. Abnormalities in protein homeostasis (proteostasis) are well established in ALS. However, they have been investigated mostly in spinal cord but less so in motor cortex. Herein, we monitored the unfolded protein (UPR) and heat shock response (HSR), two major proteostasis regulatory pathways, in human post-mortem tissue derived from the motor cortex of sporadic ALS (SALS) and compared them to those occurring in spinal cord. Although the UPR was activated in both tissues, specific expression of select UPR target genes, such as PDIs, was observed in motor cortex of SALS cases strongly correlating with oligodendrocyte markers. Moreover, we found that endoplasmic reticulum-associated degradation (ERAD) and HSR genes, which were activated predominately in spinal cord, correlated with the expression of neuronal markers. Our results indicate that proteostasis is strongly and selectively activated in SALS motor cortex and spinal cord where subsets of these genes are associated with specific cell type. This study expands our understanding of convergent molecular mechanisms occurring in motor cortex and spinal cord and highlights cell type–specific contributions. 相似文献
125.
Genevieve E. Davis Mark F. Baumgartner Peter J. Corkeron Joel Bell Catherine Berchok Julianne M. Bonnell Jacqueline Bort Thornton Solange Brault Gary A. Buchanan Danielle M. Cholewiak Christopher W. Clark Julien Delarue Leila T. Hatch Holger Klinck Scott D. Kraus Bruce Martin David K. Mellinger Hilary Moors‐Murphy Sharon Nieukirk Douglas P. Nowacek Susan E. Parks Dawn Parry Nicole Pegg Andrew J. Read Aaron N. Rice Denise Risch Alyssa Scott Melissa S. Soldevilla Kathleen M. Stafford Joy E. Stanistreet Erin Summers Sean Todd Sofie M. Van Parijs 《Global Change Biology》2020,26(9):4812-4840
Six baleen whale species are found in the temperate western North Atlantic Ocean, with limited information existing on the distribution and movement patterns for most. There is mounting evidence of distributional shifts in many species, including marine mammals, likely because of climate‐driven changes in ocean temperature and circulation. Previous acoustic studies examined the occurrence of minke (Balaenoptera acutorostrata) and North Atlantic right whales (NARW; Eubalaena glacialis). This study assesses the acoustic presence of humpback (Megaptera novaeangliae), sei (B. borealis), fin (B. physalus), and blue whales (B. musculus) over a decade, based on daily detections of their vocalizations. Data collected from 2004 to 2014 on 281 bottom‐mounted recorders, totaling 35,033 days, were processed using automated detection software and screened for each species' presence. A published study on NARW acoustics revealed significant changes in occurrence patterns between the periods of 2004–2010 and 2011–2014; therefore, these same time periods were examined here. All four species were present from the Southeast United States to Greenland; humpback whales were also present in the Caribbean. All species occurred throughout all regions in the winter, suggesting that baleen whales are widely distributed during these months. Each of the species showed significant changes in acoustic occurrence after 2010. Similar to NARWs, sei whales had higher acoustic occurrence in mid‐Atlantic regions after 2010. Fin, blue, and sei whales were more frequently detected in the northern latitudes of the study area after 2010. Despite this general northward shift, all four species were detected less on the Scotian Shelf area after 2010, matching documented shifts in prey availability in this region. A decade of acoustic observations have shown important distributional changes over the range of baleen whales, mirroring known climatic shifts and identifying new habitats that will require further protection from anthropogenic threats like fixed fishing gear, shipping, and noise pollution. 相似文献
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Robert L. Woodward Michaela M. Castleman Chelsea E. Meloche Mary E. Karpen Clare G. Carlson William H. Yobi Jacqueline C. Jepsen Benjamin W. Lewis Brooke N. Zarnosky Paul D. Cook 《Protein science : a publication of the Protein Society》2020,29(4):1021-1025
Many gram‐positive bacteria produce bacillithiol to aid in the maintenance of redox homeostasis and degradation of toxic compounds, including the antibiotic fosfomycin. Bacillithiol is produced via a three‐enzyme pathway that includes the action of the zinc‐dependent deacetylase BshB. Previous studies identified conserved aspartate and histidine residues within the active site that are involved in metal binding and catalysis, but the enzymatic mechanism is not fully understood. Here we report two X‐ray crystallographic structures of BshB from Bacillus subtilis that provide insight into the BshB catalytic mechanism. 相似文献
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Pedrotta Tiziana Gobet Erika Schwörer Christoph Beffa Giorgia Butz Christoph Henne Paul D. Morales-Molino César Pasta Salvatore van Leeuwen Jacqueline F. N. Vogel Hendrik Zwimpfer Elias Anselmetti Flavio S. Grosjean Martin Tinner Willy 《Vegetation History and Archaeobotany》2021,30(6):789-813
Vegetation History and Archaeobotany - Knowledge about the vegetation history of Sardinia, the second largest island of the Mediterranean, is scanty. Here, we present a new sedimentary record... 相似文献