Search results for "Mphi"
showing 10 items of 626 documents
Programmable assembly of peptide amphiphile via noncovalent-to-covalent bond conversion
2017
Controlling the number of monomers in a supramolecular polymer has been a great challenge in programmable self-assembly of organic molecules. One approach has been to make use of frustrated growth of the supramolecular assembly by tuning the balance of attractive and repulsive intermolecular forces. We report here on the use of covalent bond formation among monomers, compensating for intermolecular electrostatic repulsion, as a mechanism to control the length of a supramolecular nanofiber formed by self-assembly of peptide amphiphiles. Circular dichroism spectroscopy in combination with dynamic light scattering, size-exclusion chromatography, and transmittance electron microscope analyses r…
Immune-Mediated Desquamative Gingivitis and Optical Coherence Tomography Diagnostic Patterns: Clinical Implication from a Systematic Review
2021
Desquamative Gingivitis (DG) comprises heterogeneous clinical manifestations of numerous immune-mediated muco-cutaneous diseases. Optical Coherence Tomography (OCT) has been proposed as a valuable diagnostic support even if, to date, there are no standardized OCT-diagnostic patterns applicable to DGs. A systematic review was performed to detect existing data on in vivo OCT diagnostic patterns of the most common immune-mediated DGs (i.e., pemphigus vulgaris, mucous membrane pemphigoid and oral lichen planus). It has been found that OCT exhibits specific patterns that address the diagnosis of DG by pemphigus vulgaris (i.e., intraepithelial unilocular blister, reduced epithelial thickness, pre…
Grandidierella bonnieroides Stephensen, 1948 (Amphipoda, Aoridae)-first record of an established population in the Mediterranean Sea
2016
The first record in the Mediterranean Sea of the invasive aorid amphipod crustacean Grandidierella bonnieroides is presented. A widespread circumtropical species, recorded off the Saudi coast of the Arabian Gulf, the Red Sea and the Suez Canal, it may have been introduced into the Mediterranean through the Suez Canal. This tube-builder species of soft bottoms recently established a population in the polluted Haifa Bay, Israel. Further, this is the first Mediterranean record of the genus.
Two new Mediterranean Stenothoe (Crustacea, Amphipoda) from the coast of Israel
2015
Within collections along the Mediterranean coast of Israel, two new species ofStenothoe(Amphipoda) were found. They were found to be living on sand or mud and probably licking the surface of grains.
New records of amphipod crustaceans along the Israeli Mediterranean coast, including a rare Mediterranean endemic species, Maera schieckei Karaman & …
2020
A survey has been carried out at four Israeli rocky sites to evaluate the diversity of the amphipod fauna on various hard substrates, still scarcely monitored, as potential pabulum for amphipod crustacean species. A survey of shallow rocky reefs along the Mediterranean coast of Israel recovered 28 species and integrated the Amphipoda checklist for the country ofIsrael with 12 newly-recorded species. Such renewed national list includes Maera schieckei Karaman & Ruffo, 1971, a rare species endemic to the Mediterranean Sea, recorded here for the first time from the southern Levant Basin. The species, described from specimens collected in the Tyrrhenian Sea in 1970, has been only record…
The first colonization of the Genus Amphistegina and other exotic benthic foraminifera of the Pelagian Islands and south-eastern Sicily (central Medi…
2014
Abstract A detailed study of the marine sediments collected on the inner shelf of some of the selected areas of the central Mediterranean Sea has been carried out in order to verify the presence of exotic benthic foraminiferal species. Since 2000, the coastal marine environments of the Pelagian Islands and of Sicily (central Mediterranean) have been increasingly colonized by exotic species (i.e. fishes and algae) originating both from the Atlantic Ocean and the Red Sea. The studied areas (Pelagian Islands and SE Sicily) are located in the middle of the Mediterranean Sea. Therefore, they represent an ideal place to understand how exotic species, coming from different Oceans, may have coloniz…
Geometric morphometry supports a taxonomic revision of the Mediterranean Bathyporeia guilliamsoniana (Spence Bate, 1857) (Amphipoda, Bathyporeiidae)
2013
Bathyporeia guilliamsoniana (Spence Bate, 1857) specimens collected in the Levantine Basin of the Mediterranean Sea displayed polymorphism in some characters. More than 100 specimens were examined and their intra-specific variation in the shape of the third epimeral plate analysed and quantified. The morphometric geometry methodology is used to assess the ‘cryptic’ variation in shape which may obscure identification. The results support the assignment of sunnivae and megalops to morphotypes of B. guilliamsoniana sensu d’Udekem d’Acoz & Vader (2005).
(19)F NMR screening of unrelated antimicrobial peptides shows that membrane interactions are largely governed by lipids.
2014
AbstractMany amphiphilic antimicrobial peptides permeabilize bacterial membranes via successive steps of binding, re-alignment and/or oligomerization. Here, we have systematically compared the lipid interactions of two structurally unrelated peptides: the cyclic β-pleated gramicidin S (GS), and the α-helical PGLa. 19F NMR was used to screen their molecular alignment in various model membranes over a wide range of temperatures. Both peptides were found to respond to the phase state and composition of these different samples in a similar way. In phosphatidylcholines, both peptides first bind to the bilayer surface. Above a certain threshold concentration they can re-align and immerse more dee…
Polymeric Oriented Monolayers and Multilayers as Model Surfaces
1985
All living cells are surrounded by a lipid bilayer membrane in which a variety of proteins (e.g., enzymes) are embedded (fluid mosaic model; Figure 1). Phospholipids and cholesterol represent the major part of the lipids of a biomembrane. Figure 2 illustrates the structure of some typical amphiphilic membrane components with hydrophobic alkyl chains and hydrophilic head groups. The amount of protein in biological membranes varies between 40 and 60%(3); however, in highly specialized membranes values between 20% (myelin sheath of nerve axons; electrical isolator) and 75% (mitochondrial inner membrane; enzyme system of the respiratory chain) may occur. Furthermore, the incorporation of protei…
Effect of additives on the structural organization of asphaltene aggregates in bitumen
2019
Abstract Bitumens are composite materials whose complex organization hinders the rational understanding of their relationships between composition, structure and performances. So, research attempting to shed more light in this field is required. In this work Wide Angle X ray Scattering (WAXS) has been used to explore the influence of six opportunely chosen additives on the bitumen structure with the aim to ultimately correlate the findings with the bitumen performances. Diagnostic fingerprints have been observed in the WAXS profile: asphaltenes form stuck of about 18 A and constituted by about 6 asphaltene units on average. Such stucks are, in turn, organized at higher levels of complexity …