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The aim of this report was to assess the relation between heart rate response to dipyridamole infusion and perfusion defects at quantitative sestamibi single-photon emission computed tomographic imaging. We demonstrated in 166 heart transplant recipients that chronotropic incompetence to dipyridamole is the only significant and independent predictor of perfusion defects.  相似文献   
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Recombinant adenoviral vectors (rAds) are lead vaccine candidates for protection against a variety of pathogens, including Ebola, HIV, tuberculosis, and malaria, due to their ability to potently induce T cell immunity in humans. However, the ability to induce protective cellular immunity varies among rAds. Here, we assessed the mechanisms that control the potency of CD8 T cell responses in murine models following vaccination with human-, chimpanzee-, and simian-derived rAds encoding SIV-Gag antigen (Ag). After rAd vaccination, we quantified Ag expression and performed expression profiling of innate immune response genes in the draining lymph node. Human-derived rAd5 and chimpanzee-derived chAd3 were the most potent rAds and induced high and persistent Ag expression with low innate gene activation, while less potent rAds induced less Ag expression and robustly induced innate immunity genes that were primarily associated with IFN signaling. Abrogation of type I IFN or stimulator of IFN genes (STING) signaling increased Ag expression and accelerated CD8 T cell response kinetics but did not alter memory responses or protection. These findings reveal that the magnitude of rAd-induced memory CD8 T cell immune responses correlates with Ag expression but is independent of IFN and STING and provide criteria for optimizing protective CD8 T cell immunity with rAd vaccines.  相似文献   
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The use of liver magnetic resonance imaging is increasing thanks to its multiparametric sequences that allow a better tissue characterization, and the use of hepatobiliary contrast agents. This review aims to evaluate gadoxetic acid enhanced magnetic resonance imaging in the diagnosis and staging of cholangiocarcinoma and its different clinical and radiological classifications proposed in the literature. We also analyze the epidemiology, risk factors in correlation with clinical findings and laboratory data.  相似文献   
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Background

(Buccalin ®) is a Bacterial Lysates (BL) that belongs to a family of immune-stimulators, developed more than 30 years ago and it still has a role in the prophylaxis of Recurrent Respiratory Tract Infections (RRTI). However, original studies were conducted with an approach that does not seem to be aligned with the present methodologies. In addition, concomitant therapies substantially improved in the last decades. These two reasons strongly suggested to update our knowledge on the capacity of this bacterial lysate (Buccalin ®) to reduce the number of days with infectious episodes in patients with RRTI.

Methods

A double blind, placebo-controlled, randomized, multicentre study was programmed (EudraCT code: 2011-005187-25). The reduction of the number of days with infectious episodes (IE) was the primary endpoint. Secondary endpoints were the number of IE, the use of concomitant drugs, the efficacy on signs and symptoms of RRTI and the safety of the drug. Patients were treated according to the registered schedule and were followed up for a period of 6 months.

Results

From a cohort of 188 patients eligible for the study, 90 were included in the active group and 88 in the placebo group. The study was completed in 170 patients. A significant reduction of the number of days with IE was observed (6.57 days in the active group and 7.47 in the placebo group). Secondary endpoints were only partially achieved. No virtual adverse events related to the treatment were recorded.

Conclusion

The administration of bacterial lysate (Buccalin ®) in patients with RRTI had the capacity to significantly reduce the number of days with IE in a multicentre, randomized, placebo controlled, clinical study. The treatment was safe. Of note, all patients were free to be treated with the best concomitant therapies. In these conditions, the positive results observed demonstrated that this bacterial lysate has maintained its capacity of reducing the days with infections in patients with RRTI, also in association to the concomitant therapies available nowadays.
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