The Reduction in Electroporation Voltages by the Addition of a Surfactant to Planar Lipid Bilayers

AbstractThe effects of a nonionic surfactant, octaethyleneglycol mono n-dodecyl ether (C12E8), on the electroporation of planar bilayer lipid membranes made of the synthetic lipid 1-pamitoyl 2-oleoyl phosphatidylcholine (POPC), was studied. High-amplitude (∼100–450mV) rectangular voltage pulses were used to electroporate the bilayers, followed by a prolonged, low-amplitude (∼65mV) voltage clamp to monitor the ensuing changes in transmembrane conductance. The electroporation thresholds of the membranes were found for rectangular voltage pulses of given durations. The strength-duration relationship was determined over a range from 10μs to 10s. The addition of C12E8 at concentrations of 0.1, 1, and 10μM to the bath surrounding the membranes decreased the electroporation threshold monotonically with concentration for all durations (p<0.0001). The decrease from control values ranged from 10% to 40%, depending on surfactant concentration and pulse duration. For a 10-μs pulse, the transmembrane conductance 150μs after electroporation (G150) increased monotonically with the surfactant concentration (p=0.007 for 10μM C12E8). These findings suggest that C12E8 incorporates into POPC bilayers, allowing electroporation at lower intensities and/or shorter durations, and demonstrate that surfactants can be used to manipulate the electroporation threshold of lipid bilayers

Ab initio parametrised model of strain-dependent solubility of H in alpha-iron

The calculated effects of interstitial hydrogen on the elastic properties of alpha-iron from our earlier work are used to describe the H interactions with homogeneous strain fields using ab initio methods. In particular we calculate the H solublility in Fe subject to hydrostatic, uniaxial, and shear strain. For comparison, these interactions are parametrised successfully using a simple model with parameters entirely derived from ab initio methods. The results are used to predict the solubility of H in spatially-varying elastic strain fields, representative of realistic dislocations outside their core. We find a strong directional dependence of the H-dislocation interaction, leading to strong attraction of H by the axial strain components of edge dislocations and by screw dislocations oriented along the critical slip direction. We further find a H concentration enhancement around dislocation cores, consistent with experimental observations.Comment: part 2/2 from splitting of 1009.3784 (first part was 1102.0187), minor changes from previous version

The diet of otters (Lutra lutra) on the Agri river system, one of the most important presence sites in Italy: A molecular approach

Background. The Eurasian otter (Lutra lutra) underwent a strong decline in large areas of the Central-Western part of its distribution range, during the second half of the twentieth century. In Italy, only residual fragmented nuclei survive in the Central- Southern part of the peninsula. Nowadays, the otter is one of the most endangered mammals in Italy, and increasing the knowledge about the ecology of this species is a key step in defining fitting management strategies. Here we provide information about the diet of otter on the Agri river system, one of the most important presence sites in Italy, to understand both the species' food requirements and the impact on fish communities. Methods. DNA metabarcoding and High Throughput Sequencing were used on DNA extracted from spraints. We amplified DNA with a primer set for vertebrates, focusing efforts on the bulk of the otter's diet (fishes and amphibians). Results. Our findings showed that the diet of the otter was dominated by cyprinids (97.77%, and 99.14% of fishes), while amphibians represented 0.85% of the sequences analyzed. Results are in general accordance with previous studies based on morphological characterization; however, molecular analyses allow the resolving of some morphological uncertainties. Although the study area offers a very wide range of available prey, the diet of the otters shows marked selectivity. We highlighted a variation in prey consumed, in accordance with the typology of water system (i.e., river, lake, tributary). Some of the preys found in the diet were alien species introduced by man for sport fishing. Our findings could help define strategies useful for the conservation of the otter population in Southern Italy, suggesting management actions directed at avoiding fish community alterations through illegal stockings without severe controls on their taxonomic status. These introductions could result in a general reduction in the diversity of the otter's preys, affecting its predatory behavior

effects of an antioxidant protective topical formulation on eye exposed to ultraviolet irradiation a study in rabbit animal model

Ultraviolet-radiation exerts a well-known role in the development of various ocular diseases and may contribute to the progress of age-related macular degeneration. Therefore, the use of compounds able to protect the eyes from UV-induced cellular damage is challenging. The aim of this study has been to test the protective effects of an antioxidant topical formulation against UV-induced damage in rabbit eyes. Twelve male rabbits were used. Animals were divided into 4 groups of 3 animals each. Control group (CG) did not receive any irradiation and/or eye drop. The other three experimental groups were treated as follows: the first group received only UVR irradiation for 30 min, without eye drop supplementation (Irradiation group, IG), the second (G30) and the third (G60) groups received UV irradiation for 30' and 60', respectively, and eye drop supplementation (riboflavin, d-α-tocopheryl polyethylene glycol, proline, glycine, lysine and leucine solution) every 15 min for three hours. In the IG group a significant increase of oxidized glutathione (GSSG) and hydrogen peroxide (H2O2) was recorded in the aqueous humor, whereas ascorbic acid levels were significantly lower when compared to control eyes. In the groups exposed to UVR rays for 30 min, and treated with the topical antioxidant formulation, the GSSG, H2O2 and ascorbic acid levels were similar to those recorded in controls, whereas in the G60 group the three markers significantly differ from control group. In the lens, a significant decrease of alpha tocopherol and total antioxidant capacity (TAC) was recorded in IG-animals as compared to control group, whereas malondialdehyde (MDA) levels were significantly higher in UV-induced eye than in control eyes. In the G30 groups the alpha tocopherol, MDA and TAC levels do not significantly differ from those recorded in controls, whereas in the G60 group these three markers significantly differ from control group. Present findings demonstrate that topical treatment with the antioxidant formulation used herein protects ocular structures from oxidative stress induced by UV exposure in in vivo animal model

Osteoradionecrosis of the jaws due to teeth extractions during and after radiotherapy: A systematic review

Teeth extractions before or after radiotherapy (RT) could be procedures at high risk for osteoradionecrosis (ORN) onset. This systematic review was performed to investigate the ORN incidence following teeth extractions during and after RT for head and neck (H&amp;N) cancer and to evaluate any other possible risk factor. Methods: This systematic review was conducted according to PRISMA protocol, and the PROSPERO registration number was CRD42018079986. An electronic search was performed on the following search engines: PubMed, Scopus, and Web of Science. A cumulative meta‐analysis was performed. Results: Two thousand two hundred and eighty‐one records were screened, and nine were finally included. This systematic review revealed an ORN incidence of 5.8% (41 patients out of 462, 95% CI = 2.3–9.4); 3 ORN developed in the maxilla. No other clinical risk factors were detected. Conclusion: Post‐RT teeth extractions represent a major risk factor for ORN development, especially in the mandible, with a diminishing trend in the last years. Further research on other possible risk factors might improve this evidence

Effects of an antioxidant protective topical formulation on eye exposed to ultraviolet-irradiation: A study in rabbit animal model

Ultraviolet-radiation exerts a well-known role in the development of various ocular diseases and may contribute to the progress of age-related macular degeneration. Therefore, the use of compounds able to protect the eyes from UV-induced cellular damage is challenging. The aim of this study has been to test the protective effects of an antioxidant topical formulation against UV-induced damage in rabbit eyes. Twelve male rabbits were used. Animals were divided into 4 groups of 3 animals each. Control group (CG) did not receive any irradiation and/or eye drop. The other three experimental groups were treated as follows: the first group received only UVR irradiation for 30 min, without eye drop supplementation (Irradiation group, IG), the second (G30) and the third (G60) groups received UV irradiation for 30' and 60', respectively, and eye drop supplementation (riboflavin, d-α-tocopheryl polyethylene glycol, proline, glycine, lysine and leucine solution) every 15 min for three hours. In the IG group a significant increase of oxidized glutathione (GSSG) and hydrogen peroxide (H2O2) was recorded in the aqueous humor, whereas ascorbic acid levels were significantly lower when compared to control eyes. In the groups exposed to UVR rays for 30 min, and treated with the topical antioxidant formulation, the GSSG, H2O2 and ascorbic acid levels were similar to those recorded in controls, whereas in the G60 group the three markers significantly differ from control group. In the lens, a significant decrease of alpha tocopherol and total antioxidant capacity (TAC) was recorded in IG-animals as compared to control group, whereas malondialdehyde (MDA) levels were significantly higher in UV-induced eye than in control eyes. In the G30 groups the alpha tocopherol, MDA and TAC levels do not significantly differ from those recorded in controls, whereas in the G60 group these three markers significantly differ from control group. Present findings demonstrate that topical treatment with the antioxidant formulation used herein protects ocular structures from oxidative stress induced by UV exposure in in vivo animal model

Traditional Free-Ranging Livestock Farming as a Management Strategy for Biological and Cultural Landscape Diversity: A Case from the Southern Apennines

Mediterranean mountain landscapes are undergoing a widespread phenomenon of abandonment. This brings, as a consequence, the loss of traditional land use practices, such as transhumant pastoralism, as well as shrub and wood encroachment, with repercussions on the biodiversity associated with semi-open, human-managed landscapes. In this study, we focus on a mountain pasture from the Southern Apennines (Italy), where free-ranging transhumant grazing is still carried out, to quantify the effects of grazing presence and exclusion on arthropod diversity, and to qualitatively characterize the plant communities of grazed and ungrazed areas. Using field sampling, remote sensing, and semi-structured interviews, we assessed the validity of traditional cattle farming as a landscape management tool. Indeed, high diversity grasslands excluded from grazing were characterized by significantly less even and more dominated arthropod communities, as well as fewer plant species and families. Moreover, in areas that have been consistently grazed over the years, we found no forest encroachment from 1955 to 2019. However, rural communities are experiencing difficulties in keeping local traditions alive, even with current agri-environmental schemes. Thus, traditional livestock grazing can be a valuable management tool to maintain high biological and cultural diversity, even if stronger cooperation and attention to local needs is necessary

Stomatitis and vR-TkI: a review of current literature in 4369 patients

the following review was performed to answer to the question \u201cWhat is the rate of incidence of oral stomatitis in patients treated with VegF tKis?\u201

Marginal bone changes around platform-switched conical connection implants placed 1 or 2 mm subcrestally: A multicenter crossover randomized controlled trial

AbstractIntroduction:This study analyzes early marginal bone modifications occurring aroundplatform-switched implants with conical connection placed 1 or 2 mm subcrestally.Methods:This crossover randomized controlled trial enrolled partially edentulouspatients needing two implants in either the posterior maxilla or mandible. Eachpatient received two platform-switched implants with conical connection inserted2 mm (Test) and 1 mm (Control) subcrestally. Definitive abutments were immediatelyconnected and, after 4 months of unsubmerged healing, screwed metal-ceramiccrowns were delivered. Radiographs were taken at implant placement (T0), prosthesisdelivery (T1), and after 1 year of prosthetic loading (T2).Results:Fifty-one patients (25 males and 26 females; mean age 61.2 ± 12.1 years)totaling 102 implants were included in the final analysis. Mean peri-implant bonelevel (PBL) reduction from T0 to T2 was not significantly different around Test (0.49± 0.32 mm) and Control implants (0.46 ± 0.35 mm;p=0.66). Multivariate linearregression models highlighted a significant positive correlation between history ofperiodontitis and PBL reduction. At T2, no Test group implant and 6 Control groupimplants exhibited PBL below the implant platform (11.8% of Control groupimplants).Conclusion:No significant differences in peri-implant marginal bone changes weredemonstrated after 1 year of prosthetic loading between platform-switched implantswith conical connection inserted either 1 or 2 mm subcrestally. However, 2 mm sub-crestal placement resulted in deeper implant positioning at T2, with no exposure oftreated implant surface and potential preventive effect against subsequent peri-implant pathology