Effect of Membrane Exposure on Guided Bone Regeneration: A Systematic Review and Meta‐Analysis

Aims: This review aimed at investigating the effect of membrane exposure on guided bone regeneration (GBR) outcomes at peri-implant sites and edentulous ridges. Material and Methods: Electronic and manual literature searches were conducted by two independent reviewers using four databases, including MEDLINE, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials, for articles up to February 2017. Articles were included if they were human clinical trials or case series reporting outcomes of GBR procedures with and without membrane exposure. A random-effects meta-analysis was conducted, and the weighted mean difference (WMD) between the two groups and 95% confidence interval (CI) were reported. Results: Overall, eight articles were included in the quantitative analysis. The WMD of the horizontal bone gain at edentulous ridges was −76.24% (95% CI = −137.52% to −14.97%, p = .01) between sites with membrane exposure and without exposure. In addition, the WMD of the dehiscence reduction at peri- implant sites was −27.27% (95% CI of −45.87% to −8.68%, p = .004). Both analyses showed significantly favorable outcomes at the sites without membrane exposure. Conclusion: Based on the findings of this study, membrane exposure after GBR procedures has a significant detrimental influence on the outcome of bone augmentation. For the edentulous ridges, the sites without membrane exposure achieved 74% more horizontal bone gain than the sites with exposure. For peri-implant dehiscence defects, the sites without membrane exposure had 27% more defect reduction than the sites with exposure

The plant-pathogen haustorial interface at a glance

Many filamentous pathogens invade plant cells through specialized hyphae called haustoria. These infection structures are enveloped by a newly synthesized plant-derived membrane called the extrahaustorial membrane (EHM). This specialized membrane is the ultimate interface between the plant and pathogen, and is key to the success or failure of infection. Strikingly, the EHM is reminiscent of host-derived membrane interfaces that engulf intracellular metazoan parasites. These perimicrobial interfaces are critical sites where pathogens facilitate nutrient uptake and deploy virulence factors to disarm cellular defenses mounted by their hosts. Although the mechanisms underlying the biogenesis and functions of these host-microbe interfaces are poorly understood, recent studies have provided new insights into the cellular and molecular mechanisms involved. In this Cell Science at a Glance and the accompanying poster, we summarize these recent advances with a specific focus on the haustorial interfaces associated with filamentous plant pathogens. We highlight the progress in the field that fundamentally underpin this research topic. Furthermore, we relate our knowledge of plant-filamentous pathogen interfaces to those generated by other plant-associated organisms. Finally, we compare the similarities between host-pathogen interfaces in plants and animals, and emphasize the key questions in this research area

Charge-Reversal Instability in Mixed Bilayer Vesicles

Bilayer vesicles form readily from mixtures of charged and neutral surfactants. When such a mixed vesicle binds an oppositely-charged object, its membrane partially demixes: the adhesion zone recruits more charged surfactants from the rest of the membrane. Given an unlimited supply of adhering objects one might expect the vesicle to remain attractive until it was completely covered. Contrary to this expectation, we show that a vesicle can instead exhibit {\it adhesion saturation,} partitioning spontaneously into an attractive zone with definite area fraction, and a repulsive zone. The latter zone rejects additional incoming objects because counterions on the interior of the vesicle migrate there, effectively reversing the membrane's charge. The effect is strongest at high surface charge densities, low ionic strength, and with thin, impermeable membranes. Adhesion saturation in such a situation has recently been observed experimentally [H. Aranda-Espinoza {\it et al.}, {\sl Science} {\bf285} 394--397 (1999)]

Fuzzy reasoning spiking neural P systems revisited: A formalization

Research interest within membrane computing is becoming increasingly interdisciplinary.In particular, one of the latest applications is fault diagnosis. The underlying mechanismwas conceived by bridging spiking neural P systems with fuzzy rule-based reasoning systems. Despite having a number of publications associated with it, this research line stilllacks a proper formalization of the foundations.National Natural Science Foundation of China No 61320106005National Natural Science Foundation of China No 6147232

Ultra-high permeable phenine nanotube membranes for water desalination

Nanopore desalination technology hinges on high water-permeable membranes which, at the same time, block ions efficiently. In this study, we consider a recently synthesized [Science 363, 151-155 (2019)] phenine nanotube (PNT) for water desalination applications. Using both equilibrium and non-equilibrium molecular dynamics simulations, we show that the PNT membrane completely rejects salts, but permeates water at a rate which is an order-of-magnitude higher than that of all the membranes used for water filtration. We provide the microscopic mechanisms of salt rejection and fast water-transport by calculating the free-energy landscapes and electrostatic potential profiles. A collective diffusion model accurately predicts the water permeability obtained from the simulations over a wide range of pressure gradients. We propose a method to calculate the osmotic water permeability from the equilibrium simulation data and find that it is very high for the PNT membrane. These remarkable properties of PNT can be applied in various nanofluidic applications, such as ion-selective channels, ionic transistors, sensing, molecular sieving, and blue energy harvesting.Comment: 23 pages, 5 figure

Filamentous phages as building blocks for reconfigurable and hierarchical self-assembly

Filamentous bacteriophages such as fd-like viruses are monodisperse rod-like colloids that have well defined properties: diameter, length, rigidity, charge and chirality. Engineering those viruses leads to a library of colloidal rods which can be used as building blocks for reconfigurable and hierarchical self-assembly. Their condensation in aqueous solution \th{with additive polymers which act as depletants to induce} attraction between the rods leads to a myriad of fluid-like micronic structures ranging from isotropic/nematic droplets, colloid membranes, achiral membrane seeds, twisted ribbons, $\pi$-wall, pores, colloidal skyrmions, M\"obius anchors, scallop membranes to membrane rafts. Those structures and the way they shape shift not only shed light on the role of entropy, chiral frustration and topology in soft matter but it also mimics many structures encountered in different fields of science. On one hand, filamentous phages being an experimental realization of colloidal hard rods, their condensation mediated by depletion interactions constitutes a blueprint for self-assembly of rod-like particles and provides fundamental foundation for bio- or material oriented applications. On the other hand, the chiral properties of the viruses restrict the generalities of some results but vastly broaden the self-assembly possibilities

Balanced superconductor-insulator-superconductor mixer on a 9~μ\mum silicon membrane

We present a 380-520 GHz balanced superconductor-insulator-superconductor (SIS) mixer on a single silicon substrate. All radio-frequency (RF) circuit components are fabricated on a $9 \mu$m thick membrane. The intermediate frequency (IF) is separately amplified and combined. The balanced mixer chip, using Nb/Al/Al$_{2}$O$_{3}$/Nb SIS junctions, is mounted in a tellurium copper waveguide block at 4.2 K using Au beam lead contacts. We find uncorrected minimum receiver double-sideband noise temperatures of 70 K and a noise suppression of up to 18 dB, measured within a 440-495 GHz RF and a 4-8 GHz IF bandwidth, representing state-of-the-art device performance.Comment: 10 pages, 4 figures, Accepted by Superconductor Science & Technolog

New patents on topical anesthetics.

Anesthesia is defined as a total or partial loss of sensation and it may be general, local or topical, depending on the method of drug administration and area of the body affected. General anesthesia is a reversible state of unconsciousness produced by anesthetic agents, characterized by amnesia, muscle relaxation and loss of sensitivity to pain of the whole body. General anesthetic drugs can be classified into two main groups according to their predominant molecular pharmacological effects: volatile and intravenous agents. Local anesthesia produce a reversible loss of sensation in a portion of the body and it reversibly block impulse conduction along nerve axons and other excitable membrane. All local anesthetics (LA) are membrane stabilizing drugs; they reversibly decrease the rate of depolarization and repolarization of excitable membranes. They act mainly by inhibiting sodium influx through sodium-specific ion channels in the neuronal cell membrane, in particular the voltage-gated sodium channels. When the influx of sodium is interrupted, an action potential cannot arise and signal conduction is inhibited. The main local anesthetic (LA) agents for skin anesthesia are benzocaine (aminoester), prilocaine and lidocaine (aminoamides) which are commercially available as gels, ointments and creams (benzocaine and eutectic mixture of lidocaine and prilocaine) or as a bioadhesive (lidocaine) with different compositions (vehicles and excipients) for adults or pediatric use. Topical anesthetics decrease anxiety, pain and discomfort during cutaneous procedures and provide effective analgesia with rapid onset, prolonged duration and minimal side effects. This article outlines the different classes of topical anesthetics available and gives an overview of the mechanism of action, metabolism of each different class, of the possible complications that can occur because of their use and their possible treatment options and new patents. © 2014 Bentham Science Publishers