Molecular Insights into Quorum Sensing in the Human Pathogen Pseudomonas aeruginosa from the Structure of the Virulence Regulator LasR Bound to Its Autoinducer

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Nonlinear Dynamics of Magnetic Islands Imbedded in Small-Scale Turbulence

International audienceThe nonlinear dynamics of magnetic tearing islands imbedded in a pressure gradient driven turbulence is investigated numerically in a reduced magnetohydrodynamic model. The study reveals regimes where the linear and nonlinear phases of the tearing instability are controlled by the properties of the pressure gradient. In these regimes, the interplay between the pressure and the magnetic flux determines the dynamics of the saturated state. A secondary instability can occur and strongly modify the magnetic island dynamics by triggering a poloidal rotation. It is shown that the complex nonlinear interaction between the islands and turbulence is nonlocal and involves small scales

Fluorescent Light Energy (FLE) Generated through Red LED Light and a Natural Photoconverter Gel as a New, Non-Invasive Approach for Facial Age Control: A Pilot Study

This study, for the first time, evaluated the safety and efficacy of a new natural-based topical gel containing a spirulina extract. This photoconverter gel generates fluorescent light energy (FLE) via a red LED light device, which is proven to be effective for age control of facial skin. This was a one-centre, observational, uncontrolled pilot trial. Eight healthy female subjects aged 35 to 65 years old, with Fitzpatrick skin types II–V were recruited. The duration of the study was five treatment sessions of one treatment every seven days, with a final follow-up at one month after the last treatment session. The images and the related data were acquired with the SONY® Mod. DSCRX10M3, the Canfield VISIA Facial Imaging System®, and QUANTIFICARE 3D® analysis. Patient compliance was excellent (100%) and the treatment was described as warm and pleasant by the patients. After 30 days, VISIA parameters such as wrinkles, texture, red areas, and Trueskin Age® had improved. The safety and efficacy of the FLE treatment assessed in this trial were achieved for overall rejuvenation of facial skin, focusing on wrinkles evaluated via the specific VISIA algorithms

Effect of the curvature and the {\beta} parameter on the nonlinear dynamics of a drift tearing magnetic island

We present numerical simulation studies of 2D reduced MHD equations investigating the impact of the electronic \beta parameter and of curvature effects on the nonlinear evolution of drift tearing islands. We observe a bifurcation phenomenon that leads to an amplification of the pressure energy, the generation of E \times B poloidal flow and a nonlinear diamagnetic drift that affects the rotation of the magnetic island. These dynamical modifications arise due to quasilinear effects that generate a zonal flow at the onset point of the bifurcation. Our simulations show that the transition point is influenced by the \beta parameter such that the pressure gradient through a curvature effect strongly stabilizes the transition. Regarding the modified rotation of the island, a model for the frequency is derived in order to study its origin and the effect of the \beta parameter. It appears that after the transition, an E \times B poloidal flow as well as a nonlinear diamagnetic drift are generated due to an amplification of the stresses by pressure effects

Overview of the Potential Beneficial Effects of Carotenoids on Consumer Health and Well-Being

Well-known experimental research demonstrates that oxidative stress is the leading cause of the onset and progression of major human health disorders such as cardiovascular, neurological, metabolic, and cancer diseases. A high concentration of reactive oxygen species (ROS) and nitrogen species leads to damage of proteins, lipids, and DNA associated with susceptibility to chronic human degenerative disorders. Biological and pharmaceutical investigations have recently focused on exploring both oxidative stress and its defense mechanisms to manage health disorders. Therefore, in recent years there has been considerable interest in bioactive food plant compounds as naturally occurring antioxidant sources able to prevent, reverse, and/or reduce susceptibility to chronic disease. To contribute to this research aim, herein, we reviewed the beneficial effects of carotenoids on human health. Carotenoids are bioactive compounds widely existing in natural fruits and vegetables. Increasing research has confirmed that carotenoids have various biological activities, such as antioxidant, anti-tumor, anti-diabetic, anti-aging, and anti-inflammatory activities. This paper presents an overview of the latest research progress on the biochemistry and preventative and therapeutic benefits of carotenoids, particularly lycopene, in promoting human health. This review could be a starting point for improving the research and investigation of carotenoids as possible ingredients of functional health foods and nutraceuticals in the fields of healthy products, cosmetics, medicine, and the chemical industry

Clinical application of cardiac scintigraphy with bone tracers: controversies and pitfalls in cardiac amyloidosis

Cardiac amyloidosis (CA) is a life-threatening disease caused by extracellular deposition of amyloidogenic proteins in the heart tissue; it could be associated with a poor prognosis and remains underdiagnosed and underestimated. During the last years, bone scintigraphy has been widely used to facilitate the diagnosis of CA, avoid endomyocardial biopsy, and differentiate amyloid light-chain amyloidosis from transthyretin amyloidosis. Technetium-99m pyrophosphate (99mTc-PYP) is the most used tracer in the United States, but a standardized and shared acquisition protocol is still lacking; technetium-99m 3,3-diphosphono-1,2-propanodicarboxylic acid (99mTc-DPD) is widely used in Europe and can count on a more grounded data than 99mTc-PYP. Both tracers suffer from some diagnostic limitations (due to their biochemical characteristics) and pitfalls that can lead to a misdiagnosis of CA. We aim to briefly describe the main differences between 99mTc-PYP and 99mTc-DPD, analyzing the data available in the literature and highlighting the most frequent causes of misdiagnosis and pitfalls. Both 99mTc-DPD and 99mTc-PYP show good accuracy for the diagnosis of CA with high specificity and sensibility. Nevertheless, to achieve this accuracy, the correct acquisition protocols must be followed for each tracer, as suggested in the latest recommendation. Proper diagnosis of CA has a crucial role in patient management; therefore, it is important for nuclear physicians to have the most specific approaches in acquiring and interpreting bone scintigraphy for transthyretin cardiac amyloidosis

The main phenolic compounds responsible for the antioxidant capacity of sweet cherry (Prunus avium L.) pulp

The antioxidant capacity of sweet cherry (Prunus avium L.) pulp extracts is strictly related to the phenolic content, starting from the fact that the higher content of phenolic compounds corresponds to the higher antioxidant indexes. This work aims to assess which compounds characterized three cultivars, namely Ferrovia, Sweetheart, and Lapins grown in Southern Italy and mainly influenced the antioxidant capacity of their extracts. HPLC–MS/MS analyses were conducted to identify and quantify 17 flavonoids and 25 hydroxicinnamates derivatives. A significant influence of cultivar was revealed from one-way MANOVA (p < 0.05). Furthermore, the extracts were tested for their radical scavenging activity (DPPH and ABTS assays) and reducing power using the Folin–Ciocalteau method. Lapins and Sweetheart extracts, richer in phenolic compounds, returned the highest reducing power and radical scavenging capacity. Finally, a Factorial Analysis was applied to the collected data allowing reliable correlations between phenolics and antioxidant indexes

A Modified Rabbit Ulna Defect Model for Evaluating Periosteal Substitutes in Bone Engineering: A Pilot Study

The present work defines a modified critical size rabbit ulna defect model for bone regeneration in which a non-resorbable barrier membrane was used to separate the radius from the ulna to create a valid model for evaluation of tissue-engineered periosteal substitutes. Eight rabbits divided into two groups were used. Critical defects (15 mm) were made in the ulna completely eliminating periosteum. For group I, defects were filled with a nanohydroxyapatite poly(ester urethane) scaffold soaked in PBS and left as such (group Ia) or wrapped with a tissue-engineered periosteal substitute (group Ib). For group II, an expanded-polytetrafluoroethylene (e-PTFE) (GORE-TEX\uae) membrane was inserted around the radius then the defects received either scaffold alone (group IIa) or scaffold wrapped with periosteal substitute (group IIb). Animals were euthanized after 12\u201316 weeks, and bone regeneration was evaluated by radiography, computed microtomography (\ub5CT), and histology. In the first group, we observed formation of radio-ulnar synostosis irrespective of the treatment. This was completely eliminated upon placement of the e-PTFE (GORETEX\uae) membrane in the second group of animals. In conclusion, modification of the model using a non-resorbable e-PTFE membrane to isolate the ulna from the radius was a valuable addition allowing for objective evaluation of the tissue-engineered periosteal substitut