274 research outputs found
Superconducting fluctuations observed far above T<sub>c</sub> in the isotropic superconductor K<sub>3</sub>C<sub>60</sub>
Alkali-doped fullerides are strongly correlated organic superconductors that exhibit high transition temperatures, exceptionally large critical magnetic fields and a number of other unusual properties. The proximity to a Mott insulating phase is thought to be a crucial ingredient of the underlying physics, and may also affect precursors of superconductivity in the normal state above T. We report on the observation of a sizeable magneto-thermoelectric (Nernst) effect in the normal state of KC, which displays the characteristics of superconducting fluctuations. The anomalous Nernst effect emerges from an ordinary quasiparticle background below a temperature of 80K, far above T = 20K. At the lowest fields and close to T, the scaling of the effect is captured by a model based on Gaussian fluctuations. The temperature up to which we observe fluctuations is exceptionally high for a three-dimensional isotropic system, where fluctuation effects are usually suppressed
The Expression of CD154 by Kaposi's Sarcoma Cells Mediates the Anti-Apoptotic and Migratory Effects of HIV-1-Tat Protein:
Kaposi's sarcoma (KS) is a malignancy associated to conditions of immune system impairment such as HIV-1 infection and post-transplantation therapy. Here we report that HIV-1-Tat protein, at concentrations well below those detected in AIDS patients, up-regulates the expression of both CD40 and CD154 on KS cells. This occurred also in the presence of vincristine, that at doses shown to induce apoptosis decreased the expression of both CD40 and CD154 on KS cells. The treatment with a soluble CD40-muIg fusion protein (CD40 fp) that prevents the binding of CD154 with cell surface CD40, as well as the transfection with a vector for soluble CD40 (KS sCD40), decreased the anti-apoptotic effect of Tat. Moreover, Tat-induced motility of KS cells was inhibited by soluble CD40 fp. Tat also enhanced the expression of intracellular proteins known to transduce signals triggered by CD40 engagement, in particular TRAF-3. Tat as well as soluble CD154 (sCD154) prevented vincristine-induced reduction of TRAF-3 in KS cells t..
Inflammaging and Complement System: A Link Between Acute Kidney Injury and Chronic Graft Damage
The aberrant activation of complement system in several kidney diseases suggests that this pillar of innate immunity has a critical role in the pathophysiology of renal damage of different etiologies. A growing body of experimental evidence indicates that complement activation contributes to the pathogenesis of acute kidney injury (AKI) such as delayed graft function (DGF) in transplant patients. AKI is characterized by the rapid loss of the kidney’s excretory function and is a complex syndrome currently lacking a specific medical treatment to arrest or attenuate progression in chronic kidney disease (CKD). Recent evidence suggests that independently from the initial trigger (i.e., sepsis or ischemia/reperfusions injury), an episode of AKI is strongly associated with an increased risk of subsequent CKD. The AKI-to-CKD transition may involve a wide range of mechanisms including scar-forming myofibroblasts generated from different sources, microvascular rarefaction, mitochondrial dysfunction, or cell cycle arrest by the involvement of epigenetic, gene, and protein alterations leading to common final signaling pathways [i.e., transforming growth factor beta (TGF-β), p16ink4a, Wnt/β-catenin pathway] involved in renal aging. Research in recent years has revealed that several stressors or complications such as rejection after renal transplantation can lead to accelerated renal aging with detrimental effects with the establishment of chronic proinflammatory cellular phenotypes within the kidney. Despite a greater understanding of these mechanisms, the role of complement system in the context of the AKI-to-CKD transition and renal inflammaging is still poorly explored. The purpose of this review is to summarize recent findings describing the role of complement in AKI-to-CKD transition. We will also address how and when complement inhibitors might be used to prevent AKI and CKD progression, therefore improving graft function
Online hemodiafiltration inhibits inflammation-related endothelial dysfunction and vascular calcification of uremic patients modulating miR-223 expression in plasma extracellular vesicles
An ancient pointed maize rich in phlobaphenes: the "Nero Spinoso" from Valcamonica (Brescia, Italy)
The variety of the species Zea mays called \u201cNero Spinoso\u201d is a traditional crop in the Middle Valle Camonica (Northern Italy) although its cultivation was almost completely abandoned during the second half of the twentieth century due to the introduction of commercial hybrids and to a reduction in the consumption of polenta, for centuries a staple food of the rural population.
This work characterized this ancient pigmented maize. A preliminary spectrophotometric analysis revealed the presence of flavonols, phenolic acids and in particular phlobaphenes, probably responsible for ear coloration. Phlobaphenes are reddish insoluble substances synthesized in maize through the flavonoids pathway by the polymerization of flavan-4-ols. In maize this pigment is due to the presence of the pericarp1 gene (p1), a transcription factor belonging to the MYB gene family driving the accumulation of the pigment in the pericarp layer. Genetic and molecular analysis confirmed the presence of the P1 gene in this landrace and histological analysis confirmed that the pigment is accumulated in the pericarp. In the meantime HPLC analyses also showed the presence of a large amount of carotenoids and, probably thanks to the high amount of pigments, this maize variety showed very high antioxidant ability. Given the chronic disease prevention properties of antioxidant molecules, this variety could be of great interest also from a nutritional point of view. Characterization will allow an accurate description of this landrace with the aim of studying and preserving maize biodiversity in Europe and in particular in Italy. We have collaborated with the municipalities of Esine and Piancogno in the application process needed to register this ancient cultivar on the National Register of conservation varieties with the aim of valorizing this ancient landrace. The "Nero Spinoso" maize was recorded in the National Register in January 2016
Factors Associated with ICU Admission following Blunt Chest Trauma
Background. Blunt chest wall trauma accounts for over 10% of all trauma patients presenting to emergency departments worldwide. When the injury is not as severe, deciding which blunt chest wall trauma patients require a higher level of clinical input can be difficult. We hypothesized that patient factors, injury patterns, analgesia, postural condition, and positive airway pressure influence outcomes. Methods. The study population consisted of patients hospitalized with at least 3 rib fractures (RF) and at least one pulmonary contusion and/or at least one pneumothorax lower than 2 cm. Results. A total of 140 patients were retrospectively analyzed. Ten patients (7.1%) were admitted to intensive care unit (ICU) within the first 72 hours, because of deterioration of the clinical conditions and gas exchange with worsening of chest X-ray/thoracic ultrasound/chest computed tomography. On univariable analysis and multivariable analysis, obliged orthopnea (p = 0.0018) and the severity of trauma score (p < 0.0002) were associated with admission to ICU. Conclusions. Obliged orthopnea was an independent predictor of ICU admission among patients incurring non-life-threatening blunt chest wall trauma. The main therapeutic approach associated with improved outcome is the prevention of pulmonary infections due to reduced tidal volume, namely, upright postural condition and positive airway pressure
An optically stimulated superconducting-like phase in K3C60 far above equilibrium Tc
The control of non-equilibrium phenomena in complex solids is an important
research frontier, encompassing new effects like light induced
superconductivity. Here, we show that coherent optical excitation of molecular
vibrations in the organic conductor K3C60 can induce a non-equilibrium state
with the optical properties of a superconductor. A transient gap in the real
part of the optical conductivity and a low-frequency divergence of the
imaginary part are measured for base temperatures far above equilibrium Tc=20
K. These findings underscore the role of coherent light fields in inducing
emergent order.Comment: 40 pages, 23 figure
- …