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991.
992.
María Eugenia López Pilar Garcés Pablo Cuesta Nazareth P. Castellanos Sara Aurtenetxe Ricardo Bajo Alberto Marcos Mercedes Montenegro Raquel Yubero Francisco del Pozo Miguel Sancho Fernando Maestú 《Age (Dordrecht, Netherlands)》2014,36(3):1389-1406
Mild cognitive impairment (MCI) is a stage between healthy aging and dementia. It is known that in this condition the connectivity patterns are altered in the resting state and during cognitive tasks, where an extra effort seems to be necessary to overcome cognitive decline. We aimed to determine the functional connectivity pattern required to deal with an internally directed cognitive state (IDICS) in healthy aging and MCI. This task differs from the most commonly employed ones in neurophysiology, since inhibition from external stimuli is needed, allowing the study of this control mechanism. To this end, magnetoencephalographic (MEG) signals were acquired from 32 healthy individuals and 38 MCI patients, both in resting state and while performing a subtraction task of two levels of difficulty. Functional connectivity was assessed with phase locking value (PLV) in five frequency bands. Compared to controls, MCIs showed higher PLV values in delta, theta, and gamma bands and an opposite pattern in alpha, beta, and gamma bands in resting state. These changes were associated with poorer neuropsychological performance. During the task, this group exhibited a hypersynchronization in delta, theta, beta, and gamma bands, which was also related to a lower cognitive performance, suggesting an abnormal functioning in this group. Contrary to controls, MCIs presented a lack of synchronization in the alpha band which may denote an inhibition deficit. Additionally, the magnitude of connectivity changes rose with the task difficulty in controls but not in MCIs, in line with the compensation-related utilization of neural circuits hypothesis (CRUNCH) model. 相似文献
993.
994.
995.
A high-fat diet coincides with increased levels of bile acids. This increase in bile acids, particularly deoxycholic acid (DCA), has been strongly associated with the development of colon cancer. Conversely, ursodeoxycholic acid (UDCA) may have chemopreventive properties. Although structurally similar, DCA and UDCA present different biological and pathological effects in colon cancer progression. The differential regulation of cancer by these two bile acids is not yet fully understood. However, one possible explanation for their diverging effects is their ability to differentially regulate signaling pathways involved in the multistep progression of colon cancer, such as the epidermal growth factor receptor (EGFR)–mitogen-activated protein kinase (MAPK) pathway. This review will examine the biological effects of DCA and UDCA on colon cancer development, as well as the diverging effects of these bile acids on the oncogenic signaling pathways that play a role in colon cancer development, with a particular emphasis on bile acid regulation of the EGFR–MAPK pathway. 相似文献
996.
Marcos Rodríguez-Esteban Manuel Anguita Sara Miranda-Montero Juan Carlos Castillo Luis Álvarez-Acosta Francisco Castillo Rafael Llorens-León José Suárez-de Lezo 《Enfermedades infecciosas y microbiología clínica》2014
Objectives
To assess possible differences in clinical presentation, microbiology, morbidity and mortality of infective endocarditis between two Spanish hospitals, one on the mainland that has cardiac surgery and one in the Canary Islands without this service.Method
A total of 229 patients consecutively diagnosed of endocarditis between 2005 and 2012, including pediatric population, were studied in the Reina Sofía Hospital (Córdoba, n = 119) and Nuestra Señora de Candelaria Hospital (Tenerife, n = 110). We compared the clinical, microbiological and echocardiographic data and analyzed mortality differences by binary logistic regression analysis.Results
There were no differences in underlying heart disease, proportion of surgery, or the microbiological profile. The proportion of infections attributable to catheter was higher in the Canary Islands hospital (13.6% vs 3.4%). Mortality was also higher (31.8% vs 18.5%, P = .020), although this difference was no longer significant in the multivariate analysis (OR = 1.85; 95% CI, 0.70-4.87; P = .213). Age (OR = 1.04/year; 95% CI, 1.01-1.07; P = .006), cardiac complications (OR = 5.05; 95% CI, 1.78-14.34; P = .002), persistent sepsis (OR = 4.89; 95% CI, 2.09-11.46; P < .001), and emergent surgery (OR = 4.43, 95% CI, 1.75-11.19; P = .002) were independent predictors of death. Time to surgery, length of stay in the hospital without a surgical service (20 [13-30.5] vs 13 [6-25] days; P = .019) was not associated with outcome.Conclusions
There are differences in the presentation of endocarditis between two distant hospitals in Spain. The different hospital mortality can not be directly related to the presence of a surgery service. 相似文献997.
998.
Cristina Torres‐Duarte Sara Hutton Carol Vines James Moore Gary N. Cherr 《Environmental toxicology》2019,34(3):294-302
Copper and copper oxide nanomaterials (nCuO) can enter the marine environment negatively impacting mussels, an environmental and commercially relevant organism. We analyzed the effects on the immune system of adult mussels exposed to soluble copper (CuSO4, 20‐50 μg/L) or nCuO (100‐450 μg/L). CuSO4 caused significant copper accumulation in gills and cell‐free hemolymph, while nCuO caused cell damage to gills and significant copper accumulation in hemocytes, the most abundant cells in the hemolymph. Both sources of copper caused cellular toxicity in hemocytes by increasing reactive oxygen species production and lysosome abundance, and decreasing multi‐drug resistance transporter activity. Though hemocyte abundance was not affected, their in‐vitro phagocytic activity decreased, explaining the slight (but not statistically significant) increase in bacterial proliferation in mussels exposed to the pathogenic bacteria Vibrio tubiashii following copper exposure. Thus, exposure to non‐lethal concentrations of CuSO4 or nCuO can potentially increase mussel susceptibility to bacterial infections. 相似文献
999.
Jason E. Farrar Paola Quarello Ross Fisher Kelly A. O'Brien Anna Aspesi Sara Parrella Adrianna L. Henson Nancy E. Seidel Eva Atsidaftos Supraja Prakash Shahla Bari Emanuela Garelli Robert J. Arceci Irma Dianzani Ugo Ramenghi Adrianna Vlachos Jeffrey M. Lipton David M. Bodine Steven R. Ellis 《American journal of hematology》2014,89(10):985-991
Diamond Blackfan anemia (DBA), a syndrome primarily characterized by anemia and physical abnormalities, is one among a group of related inherited bone marrow failure syndromes (IBMFS) which share overlapping clinical features. Heterozygous mutations or single‐copy deletions have been identified in 12 ribosomal protein genes in approximately 60% of DBA cases, with the genetic etiology unexplained in most remaining patients. Unlike many IBMFS, for which functional screening assays complement clinical and genetic findings, suspected DBA in the absence of typical alterations of the known genes must frequently be diagnosed after exclusion of other IBMFS. We report here a novel deletion in a child that presented such a diagnostic challenge and prompted development of a novel functional assay that can assist in the diagnosis of a significant fraction of patients with DBA. The ribosomal proteins affected in DBA are required for pre‐rRNA processing, a process which can be interrogated to monitor steps in the maturation of 40S and 60S ribosomal subunits. In contrast to prior methods used to assess pre‐rRNA processing, the assay reported here, based on capillary electrophoresis measurement of the maturation of rRNA in pre‐60S ribosomal subunits, would be readily amenable to use in diagnostic laboratories. In addition to utility as a diagnostic tool, we applied this technique to gene discovery in DBA, resulting in the identification of RPL31 as a novel DBA gene. Am. J. Hematol. 89:985–991, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
1000.
Monika Engelhardt Evangelos Terpos Martina Kleber Francesca Gay Ralph W?sch Gareth Morgan Michele Cavo Niels van de Donk Andreas Beilhack Benedetto Bruno Hans Erik Johnsen Roman Hajek Christoph Driessen Heinz Ludwig Meral Beksac Mario Boccadoro Christian Straka Sara Brighen Martin Gramatzki Alessandra Larocca Henk Lokhorst Valeria Magarotto Fortunato Morabito Meletios A. Dimopoulos Hermann Einsele Pieter Sonneveld Antonio Palumbo 《Haematologica》2014,99(2):232-242
Multiple myeloma management has undergone profound changes in the past thanks to advances in our understanding of the disease biology and improvements in treatment and supportive care approaches. This article presents recommendations of the European Myeloma Network for newly diagnosed patients based on the GRADE system for level of evidence. All patients with symptomatic disease should undergo risk stratification to classify patients for International Staging System stage (level of evidence: 1A) and for cytogenetically defined high- versus standard-risk groups (2B). Novel-agent-based induction and up-front autologous stem cell transplantation in medically fit patients remains the standard of care (1A). Induction therapy should include a triple combination of bortezomib, with either adriamycin or thalidomide and dexamethasone (1A), or with cyclophosphamide and dexamethasone (2B). Currently, allogeneic stem cell transplantation may be considered for young patients with high-risk disease and preferably in the context of a clinical trial (2B). Thalidomide (1B) or lenalidomide (1A) maintenance increases progression-free survival and possibly overall survival (2B). Bortezomib-based regimens are a valuable consolidation option, especially for patients who failed excellent response after autologous stem cell transplantation (2A). Bortezomib-melphalan-prednisone or melphalan-prednisone-thalidomide are the standards of care for transplant-ineligible patients (1A). Melphalan-prednisone-lenalidomide with lenalidomide maintenance increases progression-free survival, but overall survival data are needed. New data from the phase III study (MM-020/IFM 07-01) of lenalidomide-low-dose dexamethasone reached its primary end point of a statistically significant improvement in progression-free survival as compared to melphalan-prednisone-thalidomide and provides further evidence for the efficacy of lenalidomide-low-dose dexamethasone in transplant-ineligible patients (2B). 相似文献