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71.
Vadasz Z Kessler O Akiri G Gengrinovitch S Kagan HM Baruch Y Izhak OB Neufeld G 《Journal of hepatology》2005,43(3):499-507
BACKGROUND/AIMS: Lysyl-oxidases catalyze the oxidation of lysine residues in collagen and elastin thereby promoting their polymerization. We have studied here the expression of four lysyl-oxidases in normal and diseased human liver. METHODS: The expression of the different lysyl-oxidases in paraffin embedded liver sections was studied using in-situ hybridization and immunohistochemistry. The enzymatic activity of lysyl-oxidase like protein-2 (Loxl2 or LOR-1) using a previously described lysyl-oxidase assay. RESULTS: We have found that the four lysyl-oxidases which we examined are not significantly expressed in the normal liver. By contrast, Wilson's disease and primary biliary cirrhosis (PBC) patients express lysyl-oxidase (Lox) and lysyl-oxidase like protein-2 (Loxl2 or LOR-1) in hepatocytes, and the expression is accompanied by collagen deposition around the hepatocytes. Lysyl-oxidases are also expressed in additional fibrotic liver diseases such as hepatitis B and C but in these diseases the expression is confined to the fibrotic lesions and collagen does not accumulate around hepatocytes. We have found that Loxl2 is able to oxidize lysine residues of collagen, and behaves in that respect similarly to Lox. The copper chelator D-penicillamine inhibits Loxl2 induced oxidation of collagen but the Lox inhibitor beta-aminopropionitrile did not inhibit the oxidation using a BAPN concentration at which Lox activity was completely inhibited. Loxl2 also catalyzed the oxidation of cell surface proteins on HepG2 hepatoblastoma cells and inhibited their proliferation. CONCLUSIONS: Upregulation of Lox and Loxl2 in hepatocytes of Wilson's disease and PBC patients may contribute to liver damage by various mechanisms. The upregulation of Lox and Loxl2 in Wilson's disease could perhaps be utilized for diagnostic purposes since their expression is up-regulated in hepatocytes even before the onset of fibrosis. 相似文献
72.
Adenosine receptors in regulation of dendritic cell differentiation and function 总被引:1,自引:0,他引:1
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Novitskiy SV Ryzhov S Zaynagetdinov R Goldstein AE Huang Y Tikhomirov OY Blackburn MR Biaggioni I Carbone DP Feoktistov I Dikov MM 《Blood》2008,112(5):1822-1831
Differentiation of functional dendritic cells (DCs) critically depends on the microenvironment. DCs differentiate in hypoxic tumor sites and inflamed or damaged tissue. Because local concentrations of adenosine reach high physiologically relevant levels in these conditions, we assessed the expression of adenosine receptors and the effect of their activation on differentiation of human monocytes and mouse peritoneal macrophages and hematopoietic progenitor cells (HPCs) into myeloid DCs. Stimulation of adenosine receptors skews DC differentiation toward a distinct cell population characterized by expression of both DC and monocyte/macrophage cell surface markers. Pharmacologic analysis and experiments with cells from A(2B) adenosine receptor knockout mice identified A(2B) receptor as the mediator of adenosine effects on DCs. Unlike normal myeloid DCs, adenosine-differentiated DCs have impaired allostimulatory activity and express high levels of angiogenic, pro-inflammatory, immune suppressor, and tolerogenic factors, including VEGF, IL-8, IL-6, IL-10, COX-2, TGF-beta, and IDO. They promoted tumor growth if injected into tumors implanted in mice. Using adenosine desaminase knockout animals, we showed that DCs with proangiogenic phenotype are highly abundant under conditions associated with elevated levels of extracellular adenosine in vivo. Adenosine signaling through A(2B) receptor is an important factor of aberrant DC differentiation and generation of tolerogenic, angiogenic, and proinflammatory cells. 相似文献
73.
Ghrelin secretion in humans is sexually dimorphic,suppressed by somatostatin,and not affected by the ambient growth hormone levels 总被引:11,自引:0,他引:11
Barkan AL Dimaraki EV Jessup SK Symons KV Ermolenko M Jaffe CA 《The Journal of clinical endocrinology and metabolism》2003,88(5):2180-2184
We studied plasma ghrelin and GH concentrations over a 24-h period in young healthy men and women and in patients with acromegaly. Healthy subjects were restudied after administration of GH-lowering agents, octreotide or GHRH antagonist. Ghrelin concentrations in women studied during the late follicular stage of the cycle were about 3-fold higher than in men. Suppression of GH secretion by GHRH antagonist did not alter ghrelin concentration profiles. In the presence of high GH levels (acromegaly), ghrelin levels were similar to those found in healthy men. Administration of somatostatin analog octreotide suppressed both GH and ghrelin concentration profiles. We conclude that: 1) ghrelin secretion is sexually dimorphic in humans, with women in the late follicular stage having higher levels than men; 2) ghrelin secretion is suppressed by somatostatin; and 3) GH has no influence over ghrelin secretion. 相似文献
74.
Roland Vauth Bernardo Carpiniello Jacek Turczyski Mikhail Ivanov Pierre Cherubin Marjolein Lahaye Andreas Schreiner 《International journal of methods in psychiatric research》2021,30(2)
ObjectivesTo explore clinical and demographic characteristics impacting patient functioning by determining extent of overlap in factors driving change in Personal and Social Performance (PSP) and other clinical outcomes.MethodsPost‐hoc analysis from a single‐arm trial of paliperidone extended release in adult patients with nonacute symptomatic schizophrenia. Psychosocial functioning measures: PSP, Clinical Global Impression–Severity (CGI‐S), Positive and Negative Syndrome Scale (PANSS), Short‐Form 36 (SF‐36), treatment satisfaction, sleep quality/daytime drowsiness, and Extrapyramidal Symptoms Rating Scale.ResultsHighest correlations with PSP total score change included PANSS total score change (Spearman''s r = 0.607), PANSS general psychopathology change (r = 0.579), and CGI‐S change (r = 0.569). A PSP score change of −32 predicted 90% probability of deterioration in CGI‐S (score change of ≥1). The power of PSP change to predict PANSS total score change was lower. Linear stepwise regression demonstrated independent relationships for PSP change and: PANSS total change; CGI‐S change; SF‐36 Mental Component change; treatment satisfaction at endpoint; PSP at baseline; previous psychiatric hospitalizations. R 2 = 0.55 meant that 45% of PSP variation could not be explained by other clinical outcome measures.ConclusionsPsychosocial functioning improvement is important in schizophrenia. PSP may be valuable for assessing functioning; it encompasses psychosocial and clinical factors not measured by other established assessments. 相似文献
75.
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77.
Polyakov Andrey P. Mordovskiy Alexander V. Ratushnyy Mikhail V. Rebrikova Irina V. 《Oral and maxillofacial surgery》2021,25(2):271-277
Oral and Maxillofacial Surgery - Presently, the functional reconstruction of the tongue in patients after subtotal or total glossectomy with the removal of the oral floor muscles and spearing of... 相似文献
78.
Mai Uchida Joseph Biederman John D. E. Gabrieli Jamie Micco Carlo de Los Angeles Ariel Brown Tara Kenworthy Elana Kagan Susan Whitfield-Gabrieli 《Social cognitive and affective neuroscience》2015,10(12):1738-1748
This study investigated the neural basis of individual variation in emotion regulation, specifically the ability to reappraise negative stimuli so as to down-regulate negative affect. Brain functions in young adults were measured with functional Magnetic Resonance Imaging during three conditions: (i) attending to neutral pictures; (ii) attending to negative pictures and (iii) reappraising negative pictures. Resting-state functional connectivity was measured with amygdala and dorsolateral prefrontal cortical (DLPFC) seed regions frequently associated with emotion regulation. Participants reported more negative affect after attending to negative than neutral pictures, and less negative affect following reappraisal. Both attending to negative vs neutral pictures and reappraising vs attending to negative pictures yielded widespread activations that were significantly right-lateralized for attending to negative pictures and left-lateralized for reappraising negative pictures. Across participants, more successful reappraisal correlated with less trait anxiety and more positive daily emotion, greater activation in medial and lateral prefrontal regions, and lesser resting-state functional connectivity between (a) right amygdala and both medial prefrontal and posterior cingulate cortices, and (b) bilateral DLPFC and posterior visual cortices. The ability to regulate emotion, a source of resilience or of risk for distress, appears to vary in relation to differences in intrinsic functional brain architecture. 相似文献
79.
Identification of viral genomic elements responsible for rabies virus neuroinvasiveness 总被引:10,自引:0,他引:10
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Faber M Pulmanausahakul R Nagao K Prosniak M Rice AB Koprowski H Schnell MJ Dietzschold B 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(46):16328-16332
Attenuated tissue culture-adapted and natural street rabies virus (RV) strains differ greatly in their neuroinvasiveness. To identify the elements responsible for the ability of an RV to enter the CNS from a peripheral site and to cause lethal neurological disease, we constructed a full-length cDNA clone of silver-haired bat-associated RV (SHBRV) strain 18 and exchanged the genes encoding RV proteins and genomic sequences of this highly neuroinvasive RV strain with those of a highly attenuated nonneuroinvasive RV vaccine strain (SN0). Analysis of the recombinant RV (SB0), which was recovered from SHBRV-18 cDNA, indicated that this RV is phenotypically indistinguishable from WT SHBRV-18. Characterization of the chimeric viruses revealed that in addition to the RV glycoprotein, which plays a predominant role in the ability of an RV to invade the CNS from a peripheral site, viral elements such as the trailer sequence, the RV polymerase, and the pseudogene contribute to RV neuroinvasiveness. Analyses also revealed that neuroinvasiveness of an RV correlates inversely with the time necessary for internalization of RV virions and with the capacity of the virus to grow in neuroblastoma cells. 相似文献
80.
Lawrence A. Leiter Deepak L. Bhatt Darren K. McGuire Hwee Teoh Kim Fox Tabassome Simon Shamir R. Mehta Eli I. Lev Róbert G. Kiss Anthony J. Dalby Héctor Bueno Wilhelm Ridderstråle Anders Himmelmann Jayne Prats Yuyin Liu Jane J. Lee John Amerena Mikhail N. Kosiborod Philippe Gabriel Steg 《Journal of the American College of Cardiology》2021,77(19):2366-2377
BackgroundTHEMIS (The Effect of Ticagrelor on Health Outcomes in Diabetes Mellitus Patients Intervention Study) (n = 19,220) and its pre-specified THEMIS-PCI (The Effect of Ticagrelor on Health Outcomes in Diabetes Mellitus Patients Intervention Study-Percutaneous Coronary Intervention) (n = 11,154) subanalysis showed, in individuals with type 2 diabetes mellitus (median duration 10.0 years; HbA1c 7.1%) and stable coronary artery disease without prior myocardial infarction (MI) or stroke, that ticagrelor plus aspirin (compared with placebo plus aspirin) produced a favorable net clinical benefit (composite of all-cause mortality, MI, stroke, fatal bleeding, and intracranial bleeding) if the patients had a previous percutaneous coronary intervention.ObjectivesIn these post hoc analyses, the authors examined whether the primary efficacy outcome (cardiovascular death, MI, stroke: 3-point major adverse cardiovascular events [MACE]), primary safety outcome (Thrombolysis In Myocardial Infarction–defined major bleeding) and net clinical benefit varied with diabetes-related factors.MethodsOutcomes were analyzed across baseline diabetes duration, HbA1c, and antihyperglycemic medications.ResultsIn THEMIS, the incidence of 3-point MACE increased with diabetes duration (6.7% for ≤5 years, 11.1% for >20 years) and HbA1c (6.4% for ≤6.0%, 11.8% for >10.0%). The relative benefits of ticagrelor plus aspirin on 3-point MACE reduction (hazard ratio [HR]: 0.90; p = 0.04) were generally consistent across subgroups. Major bleeding event rate (overall: 1.6%) did not vary by diabetes duration or HbA1c and was increased similarly by ticagrelor across all subgroups (HR: 2.32; p < 0.001). These findings were mirrored in THEMIS-PCI. The efficacy and safety of ticagrelor plus aspirin did not differ by baseline antihyperglycemic therapy. In THEMIS-PCI, but not THEMIS, ticagrelor generally produced favorable net clinical benefit across diabetes duration, HbA1c, and antihyperglycemic medications.ConclusionTicagrelor plus aspirin yielded generally consistent and favorable net clinical benefit across the diabetes-related factors in THEMIS-PCI but not in the overall THEMIS population. 相似文献