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51.
Constantine Dimitrakakis Flora Zagouri Alexandra Tsigginou Spyros Marinopoulos Theodoros N. Sergentanis Antonis Keramopoulos George C. Zografos Konstantina Ampela Dimosthenis Mpaltas Christos Papadimitriou Meletios-Athanassios Dimopoulos Aris Antsaklis 《Breast care (Basel, Switzerland)》2013,8(3):203-207
Zusammenfassung
Hintergrund: Die Auswirkungen einer Schwangerschaft auf die Prognose des Mammakarzinoms werden in der Literatur kontrovers diskutiert. Wir haben eine gepaarte Fall-Fall-Studie konzipiert, in der schwangerschaftsasso-ziierte Mammakarzinom (SAM)-Fälle entsprechend ihres Stadiums, Alters und Jahr der Diagnosestellung mit Mammakarzinom-Patientinnen gepaart wurden. Patientinnen und Methoden: 39 aufeinanderfolgende SAM-Fälle wurden mit 39 prämenopausalen Fällen von Brust-krebs gepaart. Univariate und multivariate Überlebens-analysen mit Anpassung an Stadium, Grad, Östrogen-rezeptorstatus und Alter zum Zeitpunkt der Diagnose wurden durchgeführt. Ergebnisse: Hinsichtlich des Gesamtüberlebens deutete die univariate Analyse auf ein längeres Gesamtüberleben für nicht-SAM-Fälle vs. SAM-Fälle hin. Gleichzeitig war ein fortgeschritteneres Stadium ein Prädiktor für ein kürzeres Überleben. Die multivariate Analyse bestätigte die unabhängige ver-schlechternde Auswirkung einer Schwangerschaft. Inter-essanterweise ergab eine genestete Post-hoc-Analyse der SAM-Fälle Hinweise auf ein kürzeres Gesamtüberleben für das dritte Trimester. Die oben erwähnten Ergebnisse für das Gesamtüberleben konnten desweiteren bei der Untersuchung des rezidivfreien Überlebens reproduziert werden. Schlussfolgerung: Mit ihrem gepaarten Fall-Fall-Design deutet die vorliegende Studie darauf hin, dass Schwangerschaft ein schlechter Prognosefaktor beim Mammakarzinom ist. 相似文献52.
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Nitrate sensing and metabolism modulate motility, biofilm formation, and virulence in Pseudomonas aeruginosa 下载免费PDF全文
Infection by the bacterial opportunist Pseudomonas aeruginosa frequently assumes the form of a biofilm, requiring motility for biofilm formation and dispersal and an ability to grow in nutrient- and oxygen-limited environments. Anaerobic growth by P. aeruginosa is accomplished through the denitrification enzyme pathway that catalyzes the sequential reduction of nitrate to nitrogen gas. Mutants mutated in the two-component nitrate sensor-response regulator and in membrane nitrate reductase displayed altered motility and biofilm formation compared to wild-type P. aeruginosa PAO1. Analysis of additional nitrate dissimilation mutants demonstrated a second level of regulation in P. aeruginosa motility that is independent of nitrate sensor-response regulator function and is associated with nitric oxide production. Because motility and biofilm formation are important for P. aeruginosa pathogenicity, we examined the virulence of selected regulatory and structural gene mutants in the surrogate model host Caenorhabditis elegans. Interestingly, the membrane nitrate reductase mutant was avirulent in C. elegans, while nitrate sensor-response regulator mutants were fully virulent. The data demonstrate that nitrate sensing, response regulation, and metabolism are linked directly to factors important in P. aeruginosa pathogenesis. 相似文献
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James McCauley Constantine Bitsaktsis Jessica Cottrell 《Journal of orthopaedic research》2020,38(8):1693-1702
Fracture repair is a complex process requiring heterotypic interactions between osteogenic cells and immune cells. Recent evidence indicates that macrophages are critically involved in fracture repair. Polarized macrophage populations differentially promote and regulate inflammation in other tissues, but little is known about the various macrophage subtypes and their signaling activities following a bone fracture. The authors hypothesized that classically activated (M1 subtype) and alternatively activated (M2 subtype) macrophages are active during the early repair process to initiate and regulate the inflammatory response. To test our hypothesis, bone marrow was collected from intact femurs (naïve group), contralateral and fractured femurs of mice on days 0, 1, 2, 4, and 7 postfracture. Macrophages were isolated from the bone marrow and macrophage subtypes were identified using flow cytometry with antibodies to F4/80, MHC II, CD86, CD11c, and CD40. Bone marrow cytokine levels were measured using xMAP. Flow cytometry revealed dynamic changes in M1 subtype (F4/80+/MHC II+/CD86+), M2 subtype (F4/80+/MHC II−/CD86−), and dendritic cell (DCs; MHCII+/CD11c+/CD40+) populations following fracture as compared to naïve controls. M1 subtype levels were correlated with IL-1α, IL-1ß, IL-2, IL-17, Eotaxin, and MCP-1, while DCs were correlated with IL-6, G-CSF, LIF, KC, and VEGF-A. The results indicate that M1 and M2 subtypes and DCs are recruited to the fracture site early during the repair process and consequently may work in tandem to regulate the inflammatory response required to recruit osteogenic cells needed for later stages of repair. 相似文献
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S Constantine D Roach S Liberali A Kiermeier P Sarkar J Jannes P Sambrook P Anderson J Beltrame 《Australian dental journal》2019,64(1):4-10
It is unclear whether incidental carotid artery calcification (CAC) on radiographs has a defined relationship to clinically significant carotid artery stenosis, and therefore risk of stroke. The primary objective of this study was to ascertain the relationship between dental radiograph detected carotid calcification and carotid artery stenoses ≥50% on carotid duplex ultrasound. We carried out an observational study of patients undergoing routine dental orthopantomogram (OPG) examinations. Consecutive patients with CAC on OPG were prospectively matched to those without CAC based on age and gender. Ultrasound of the carotid arteries was performed to determine the presence of stenosis (≥50%) in either vessel. Of 5780 consecutive OPG examinations with suitable images for analysis, CAC was detected in 10.8%. A total of 233 patients underwent carotid ultrasound (130 with and 103 without CAC on OPG). The prevalence of a clinically significant (≥50%) carotid stenosis on ultrasound was 15.4% (20/130) in those with CAC and 5.8% (6/103) for those without CAC on OPG. Incidental CAC detected on routine OPG requires both radiological reporting and clinical follow‐up since 1 in 7 patients will have a clinically significant carotid artery stenosis as compared with 1 in 20 patients who do not have CAC. Trial Registration: Australian and New Zealand Clinical Trials Registry website (U1111‐1148‐1066). http://www.ANZCTR.org.au/ACTRN12613001038785.aspx 相似文献