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31.
Enrique Quintero Marta Carrillo Maria-Liz Leoz Joaquin Cubiella Carla Gargallo Angel Lanas Luis Bujanda Antonio Z. Gimeno-García Manuel Hernández-Guerra David Nicolás-Pérez Inmaculada Alonso-Abreu Juan Diego Morillas Francesc Balaguer Alfonso Muriel 《PLoS medicine》2016,13(5)
BackgroundFirst-degree relatives (FDR) of patients with colorectal cancer have a higher risk of developing colorectal cancer than the general population. For this reason, screening guidelines recommend colonoscopy every 5 or 10 y, starting at the age of 40, depending on whether colorectal cancer in the index-case is diagnosed at <60 or ≥60 y, respectively. However, studies on the risk of neoplastic lesions are inconclusive. The aim of this study was to determine the risk of advanced neoplasia (three or more non-advanced adenomas, advanced adenoma, or invasive cancer) in FDR of patients with colorectal cancer compared to average-risk individuals (i.e., asymptomatic adults 50 to 69 y of age with no family history of colorectal cancer).ConclusionsIndividuals having two FDR with colorectal cancer showed an increased risk of advanced neoplasia compared to those with average-risk for colorectal cancer. Men had over 2-fold higher risk of advanced neoplasia than women, independent of family history. These data suggest that screening colonoscopy guidelines should be revised in the familial-risk population. 相似文献
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Eva Venegas‐Moreno Alvaro Flores‐Martinez Elena Dios Mari C. Vazquez‐Borrego Alejandro Ibaez‐Costa Ainara Madrazo‐Atutxa Miguel A. Japn Justo P. Castao Raúl M. Luque David A. Cano Alfonso Soto‐Moreno 《Journal of cellular and molecular medicine》2019,23(5):3088-3096
Acromegaly is a rare disease resulting from hypersecretion of growth hormone (GH) and insulin‐like growth factor 1 (IGF1) typically caused by pituitary adenomas, which is associated with increased mortality and morbidity. Somatostatin analogues (SSAs) represent the primary medical therapy for acromegaly and are currently used as first‐line treatment or as second‐line therapy after unsuccessful pituitary surgery. However, a considerable proportion of patients do not adequately respond to SSAs treatment, and therefore, there is an urgent need to identify biomarkers predictors of response to SSAs. The aim of this study was to examine E‐cadherin expression by immunohistochemistry in fifty‐five GH‐producing pituitary tumours and determine the potential association with response to SSAs as well as other clinical and histopathological features. Acromegaly patients with tumours expressing low E‐cadherin levels exhibit a worse response to SSAs. E‐cadherin levels are associated with GH‐producing tumour histological subtypes. Our results indicate that the immunohistochemical detection of E‐cadherin might be useful in categorizing acromegaly patients based on the response to SSAs. 相似文献
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Benjamin J. Pinchbeck Manuel J. Soriano‐Laguna Matthew J. Sullivan Victor M. Luque‐Almagro Gary Rowley Stuart J. Ferguson M. Dolores Roldn David J. Richardson Andrew J. Gates 《Molecular microbiology》2019,111(6):1592-1603
Nitrate is available to microbes in many environments due to sustained use of inorganic fertilizers on agricultural soils and many bacterial and archaeal lineages have the capacity to express respiratory (Nar) and assimilatory (Nas) nitrate reductases to utilize this abundant respiratory substrate and nutrient for growth. Here, we show that in the denitrifying bacterium Paracoccus denitrificans, NarJ serves as a chaperone for both the anaerobic respiratory nitrate reductase (NarG) and the assimilatory nitrate reductase (NasC), the latter of which is active during both aerobic and anaerobic nitrate assimilation. Bioinformatic analysis suggests that the potential for this previously unrecognized role for NarJ in functional maturation of other cytoplasmic molybdenum‐dependent nitrate reductases may be phylogenetically widespread as many bacteria contain both Nar and Nas systems. 相似文献
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Saranna Fanning Aftabul Haque Thibaut Imberdis Valeriya Baru M. Inmaculada Barrasa Silke Nuber Daniel Termine Nagendran Ramalingam Gary P.H. Ho Tallie Noble Jackson Sandoe Yali Lou Dirk Landgraf Yelena Freyzon Gregory Newby Frank Soldner Elizabeth Terry-Kantor Tae-Eun Kim Dennis Selkoe 《Molecular cell》2019,73(5):1001-1014.e8
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The neutral exopolysaccharide produced by Lactobacillus delbrueckii ssp. bulgaricus LBB.B26 in skimmed milk was found to be composed of d-glucose and d-galactose in a molar ratio of 2:3. Linkage analysis and 1D/2D NMR ((1)H and (13)C) studies performed on the native polysaccharide, and on an oligosaccharide obtained from a partial acid hydrolysate of the native polysaccharide, showed the polysaccharide to consist of branched pentasaccharide repeating units with the following structure. [structure: see text] 相似文献
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Tato I Matilla I Arechaga I Zunzunegui S de la Cruz F Cabezon E 《The Journal of biological chemistry》2007,282(35):25569-25576
Conjugative systems contain an essential integral membrane protein involved in DNA transport called the Type IV coupling protein (T4CP). The T4CP of conjugative plasmid R388 is TrwB, a DNA-dependent ATPase. Biochemical and structural data suggest that TrwB uses energy released from ATP hydrolysis to pump DNA through its central channel by a mechanism similar to that used by F1-ATPase or ring helicases. For DNA transport, TrwB couples the relaxosome (a DNA-protein complex) to the secretion channel. In this work we show that TrwA, a tetrameric oriT DNA-binding protein and a component of the R388 relaxosome, stimulates TrwBDeltaN70 ATPase activity, revealing a specific interaction between the two proteins. This interaction occurs via the TrwA C-terminal domain. A 68-kDa complex between TrwBDeltaN70 and TrwA C-terminal domain was observed by gel filtration chromatography, consistent with a 1:1 stoichiometry. Additionally, electron microscopy revealed the formation of oligomeric TrwB complexes in the presence, but not in the absence, of TrwA protein. TrwBDeltaN70 ATPase activity in the presence of TrwA was further enhanced by DNA. Interestingly, maximal ATPase rates were achieved with TrwA and different types of dsDNA substrates. This is consistent with a role of TrwA in facilitating the interaction between TrwB and DNA. Our findings provide a new insight into the mechanism by which TrwB recruits the relaxosome for DNA transport. The process resembles the mechanism used by other DNA-dependent molecular motors, such as the RuvA/RuvB system, to be targeted to the DNA followed by hexamer assembly. 相似文献