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91.
There is in vitro evidence to support the notion that directed migration (chemotaxis) is involved in the recruitment of alveolar macrophages in vivo. Because O2 is widely used in the treatment of pulmonary diseases, we examined the effect of hyperoxia on migration of guinea pig alveolar macrophages in vitro. Migration was measured in blind-well chambers incubated in either room air or hyperoxia. N-formyl-methionyl-phenylalanine was used to stimulate random migration and to produce directed migration. Migration was quantified by counting the number of mononuclear cells per oil immersion field that had migrated completely through a polycarbonate filter with 5-micrometer pores. The average PO2 in the cell suspensions incubated in room air was 100 mm Hg. In the hyperoxic environments, the average PO2 at 1 h was 260 mm Hg, whereas at 2 and 3 h, it was 410 and 425 mm Hg, respectively. In 6 separate experiments, there was no significant difference between the mean response to N-formyl-methionyl phenylalanine in hyperoxia and in room air after 1 h of incubation. After 2 and 3h of incubation, however, the response in hyperoxia was significantly (P less than 0.002) lower than that in room air. The decreased response in hyperoxia did not appear to result from loss of viability of responding cells, diminished adherence of cells to the filters, loss of activity of N-formyl-methionyl phenylalanine exposed to high PO2, or failure of the cells to exhibit directed migration. Instead, it appeared that hyperoxia decreased the response of alveolar macrophages primarily by impairing random migration. 相似文献
92.
Pre-Menopausal Breast Fat Density Might Predict MACE During 10 Years of Follow-Up: The BRECARD Study
Celestino Sardu Gianluca Gatta Gorizio Pieretti Luigi Viola Cosimo Sacra Graziella Di Grezia Lanfranco Musto Salvatore Minelli Daniele La Forgia Mariangela Capodieci Alessandro Galiano Angela Vestito Angela De Lisio Pia Clara Pafundi Ferdinando Carlo Sasso Salvatore Cappabianca Gianfranco Nicoletti Giuseppe Paolisso Raffaele Marfella 《JACC: Cardiovascular Imaging》2021,14(2):426-438
ObjectivesThis study sought to determine whether the breast gland adipose tissue is associated with different rates of major adverse cardiac events (MACEs) in pre-menopausal women.BackgroundTo our knowledge, no study investigated the impact of breast adipose tissue infiltration on MACEs in pre-menopausal women.MethodsProspective multicenter cohort study conducted on pre-menopausal women >40 years of age without cardiovascular disease and breast cancer at enrollment. The study started in January 2000 and ended in January 2009, and the end of the follow-up for the evaluation of MACEs was in January 2019. Participants underwent mammography to evaluate breast density and were divided into 4 groups according to their breast density. The primary endpoint was the probability of a MACE at 10 years of follow-up in patients staged for different breast deposition/adipose tissue deposition.ResultsThe propensity score matching divided the baseline population of 16,763 pre-menopausal women, leaving 3,272 women according to the category of breast density from A to D. These women were assigned to 4 groups of the study according to baseline breast density. At 10 years of follow-up, we had 160 MACEs in group 1, 62 MACEs in group 2, 27 MACEs in group 3, and 16 MACEs in group 4. MACEs were predicted by the initial diagnosis of lowest breast density (hazard ratio: 3.483; 95% confidence interval: 1.476 to 8.257). Further randomized clinical trials are needed to translate the results of the present study into clinical practice. The loss of ex vivo breast density models to study the cellular/molecular pathways implied in MACE is another study limitation.ConclusionsAmong pre-menopausal women, a higher evidence of adipose tissue at the level of breast gland (lowest breast density, category A) versus higher breast density shows higher rates of MACEs. Therefore, the screening mammography could be proposed in overweight women to stage breast density and to predict MACEs. (Breast Density in Pre-menopausal Women Is Predictive of Cardiovascular Outcomes at 10 Years of Follow-Up [BRECARD]; NCT03779217) 相似文献
93.
Dr. Gian Daniele Zannino Roberta Perri Patrizio Pasqualetti Carlo Caltagirone Giovanni A. Carlesimo 《Cognitive neuropsychology》2013,30(4):515-540
Current feature-based semantic memory models assume that the semantic representations of concepts differ systematically across living and nonliving categories and that such differences account for the emergence of category-specific semantic deficits in brain-damaged people. To assess some of the different models' main assumptions about structural differences at the semantic feature level in the two major semantic domains, we administrated a feature-listing task to normal young volunteers on 64 concepts drawn from living and nonliving semantic categories. We investigated whether feature correlation, a variable with a crucial role in the emergence of category-specific deficits, should be computed as a concept-dependent or as a concept-independent measure, and we chose the former. We also addressed the issue of a psychological counterpart of feature production frequency. Finally, we analysed the database obtained from the feature-listing tasks, looked at cross-domain differences for correlation, feature frequency, distinctiveness, and feature type, and discussed the implications of these findings for current semantic memory models. 相似文献
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Edoardo Conte Daniele Andreini Marco Magnoni Serge Masson Saima Mushtaq Sergio Berti Mauro Canestrari Giancarlo Casolo Domenico Gabrielli Roberto Latini Paolo Marraccini Tiziano Moccetti Maria Grazia Modena Gianluca Pontone Marco Gorini Aldo P. Maggioni Attilio Maseri 《Journal of Cardiovascular Computed Tomography》2021,15(1):73-80
BackgroundHigh-risk coronary atherosclerosis features evaluated coronary CT angiography (CCTA) were suggested to have a prognostic role. The present study aimed to evaluate the association of circulating biomarkers with high-risk plaque features assessed by CCTA.MethodsA consecutive cohort of subjects who underwent CCTA because of suspected CAD was screened for inclusion in the CAPIRE study. Based on risk factors (RF) burden patients were defined as having a low clinical risk (0–1 RF with the exclusion of patients with diabetes mellitus as single RF) or an high clinical risk (≥3 RFs). In all patients, measurement of inflammatory biomarkers and CCTA analysis focused on high-risk plaque features were performed. Univariate and multivariate logistic regression analysis were used to evaluate the relationship between clinical and biological variables with CCTA advanced plaque features.Results528 patients were enrolled in CAPIRE study. Older age and male sex appeared to be predictors of qualitative high-risk plaque features and associated with the presence of elevated total, non-calcified and low-attenuation plaque volume. Among circulating biomarkers only hs-CRP was found to be associated with qualitative high-risk plaque features (OR 2.02, p = 0.004 and 2.02, p = 0.012 for LAP and RI > 1.1, respectively) with borderline association with LAP-Vol (OR 1.52, p = 0.076); HbA1c and PTX-3 resulted to be significantly associated with quantitative high-risk plaque features (OR 1.71, p = 0.003 and 1.04, p = 0.002 for LAP-Vol, respectively).ConclusionsOur results support the association between inflammatory biomarkers (hs-CRP, PTX- 3), HbA1c and high-risk atherosclerotic features detected by CCTA. Male sex and older age are significant predictors of high-risk atherosclerosis. 相似文献
99.
Todd C. Villines Subhi J. Al’Aref Daniele Andreini Marcus Y. Chen Andrew D. Choi Carlo N. De Cecco Damini Dey James P. Earls Maros Ferencik Heidi Gransar Harvey Hecht Jonathon A. Leipsic Michael T. Lu Mohamed Marwan Pál Maurovich-Horvat Edward Nicol Gianluca Pontone Jonathan Weir-McCall Gudrun M. Feuchtner 《Journal of Cardiovascular Computed Tomography》2021,15(2):180-189
100.
Salvalaggio Alessandro Coraci Daniele Cacciavillani Mario Obici Laura Mazzeo Anna Luigetti Marco Pastorelli Francesca Grandis Marina Cavallaro Tiziana Bisogni Giulia Lozza Alessandro Gemelli Chiara Gentile Luca Ermani Mario Fabrizi Gian Maria Plasmati Rosaria Campagnolo Marta Castellani Francesca Gasparotti Roberto Martinoli Carlo Padua Luca Briani Chiara 《Journal of neurology》2021,268(1):189-198
Journal of Neurology - Diagnostic delay of hereditary transthyretin amyloidosis (ATTRv, v for variant) prevents timely treatment and, therefore, concurs to the mortality of the disease. The aim of... 相似文献