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The mineralized dermal layer (MDL) is found in most terrestrial anurans. Its thickness represents on average up to 8% of that of the entire skin. It has been proposed that it may reduce body water loss, act on homeostasis, support skin structure, or conversely, it may be a currently functionless trait constrained by groups' evolutionary history. We described the MDL morphology of 11 Brachycephalus species, terrestrial, miniaturized and microendemic anurans, and tested for its relationship with climate of higher latitude regions of the Atlantic Rainforest of Brazil. All species presented MDL, described with two distinct morphological patterns: homogeneous or heterogeneous MDL, the latter distinguishable by MDL with dorsal or lateral expansion, sometimes up to the limit of the epidermis and comprising up to 50% of the thicknesses of the entire skin. Climate differed between locations by MDL morphological group, less rainy or seasonally less rainy where species with heterogeneous MDL occur. Our results indicate that the abundance of calcium in MDL and its heterogeneous condition suggest its adaptive function in reduce water loss. Such adaptations in anurans in very humid highlands reinforce the mountains' propensity for rapid loss of humidity, demystifying them as an extremely abundant source of water. This is the third study that tested the relationship between the MDL morphology and the environment where species occur and the first that correlated this structure with the climate of anurans of the same habit and distributed in a single habitat, the Atlantic Rainforest. [ABSTRACT FROM AUTHOR]

Superaustenitic stainless steel Alloy 926 was evaluated after different isothermal annealing and thermomechanical heat treatments. The impact of two different quenching and tempering processes on sensitization was determined. Since Alloy 926 contains large amounts of molybdenum and chromium, precipitation of various intermetallic phases is strongly favored. Based on SEM and EF-TEM, it was found that the size as well as the extent of elemental depletion zones is in good agreement with the degree of sensitization (DOS), independently of the applied corrosion test. Elemental depletion zones of two isothermally annealed conditions were obtained quantitatively and related to those of thermo-mechanically rolled samples. Comparison of both annealed conditions revealed the different operating principles of Streicher test and DL-EPR-test. In consequence, morphology, distribution, and chemical composition of precipitates have a considerable impact on corrosion test results. Different microstructural parameters and their relevance on prediction of corrosion properties are pointed out and discussed accurately. [ABSTRACT FROM AUTHOR]

It is known that advanced and ultra-high strength steel grades (AHSS and UHSS) are susceptible to hydrogen embrittlement under certain test conditions . In this study, punched hole specimens for constant load testing with in situ hydrogen charging were used to quantify the effect of different corrosive conditions. Flowing or stagnant electrolyte (5% NaCl) conditions were established and time to failure was recorded as a function of applied tensile stress. The pH of the solution was set at 2, 7, and 12. Bare and zinc-galvanized (EG) specimens were used. Hydrogen uptake as a function of immersion time was characterized. [ABSTRACT FROM AUTHOR]

Studies towards the impact of solute hydrogen on the mechanical properties of ultra-high strength sheet steel grades (UHSS) for the automotive industry have been increasingly conducted in the past years. This paper focuses on the pre-damaging of a dualphase DP-1000 automotive sheet steel, as found in the manufacturing of automotive body parts, in connection with hydrogen embrittlement. It is shown that the kind of pre-damaging of the specimens has a severe influence on the occurrence of hydrogen embrittlement. Hydrogen embrittlement resistance under corrosive conditions was determined through constant load tests. Tensile specimens, manufactured from electrolytically zinc galvanized DP-1000 steel, were immersed in a 5% sodium chloride solution. The impact of material properties, pre-damaging and specimen geometry are critically discussed. Furthermore a discussion is given about the material testing methods most suitable to indicate high or low hydrogen embrittlement resistance if constant load testing is performed. [ABSTRACT FROM AUTHOR]

In this work, three different hot-dip galvanizing alloys ZnAl0.2, ZnAl5, and ZnAl2Mg2 were tested in non-standardized salt spray tests. In those non-standardized salt spray tests, samples were exposed to different pH values, calcium and magnesium ions. The corrosion products formed on the alloys in different conditions were analyzed with XRD and Raman spectroscopy. Additionally, the corrosion behavior of the samples was investigated by studying cross-section cuts with SEM. By analyzing the corrosion products formed on different samples a theory about the beneficial effect of magnesium in terms of corrosion behavior was developed. [ABSTRACT FROM AUTHOR]

In this work the hot-dip galvanising coating ZnAl2Mg2 was tested against the reference material ZnAl0.2 in nonstandardised salt spray test. In those tests the samples were exposed to the sodium salts of sulphate, nitrate, phosphate and acetate. The corrosion products formed on the alloys were analysed with XRD. Additionally the corrosion behaviour of the samples was investigated by studying cross-section cuts with SEM. With this information the corrosivity of the different anions in relation to chloride ions and their corrosion behaviour could be determined. [ABSTRACT FROM AUTHOR]

The influence of parameters of a thermo-mechanical rolling process on corrosion properties of materials 316L and Alloy 825 was studied by means of the DL-EPR-method and a conventional corrosion test. Prior to polarization measurements, optimization of the DL-EPR-method was conducted. SEM was used to characterize microstructure and type of attack before and after corrosion testing. A strong correlation between annual corrosion rates and DL-EPR-test results was obtained. Due to the low tendency of both alloys to form corrosion-promoting precipitates, the applicable range of process parameters for both alloys is large and the fabrication process in general is not critical. [ABSTRACT FROM AUTHOR]

In order to achieve a reasonable lifetime of automotive exhaust components, a large number of high alloyed ferritic and austenitic stainless steels are used nowadays. It is a common concept that the lifetime of a component is directly related to the performance of steel against corrosion. The components are divided into different sections depending on their service temperatures. High temperature oxidation resistance is one of the properties which are required in different sections. The effect of material sensitization on corrosion resistance of stainless steels is well understood from the literature. Besides, sensitization materials in exhaust systems have to withstand different cyclic heating and cooling phases. The objective of this study was to develop a basic understanding that can determine the influence of different temperature treatments on stainless steels. A fundamental understanding on the interaction of sensitization and cyclic heat impacts are presented in the paper. [ABSTRACT FROM AUTHOR]

Psoriatic arthritis (PsA) is an inflammatory joint disease, characterized by extensive bone resorption, whose mechanisms have not been fully elucidated. Thus, in the present study we investigated the involvement of RANKL, TNFα, and IL-7 in the osteoclastogenesis of PsA patients. In vitro osteoclastogenesis models, consisting of unfractionated and T-cell-depleted mononuclear cells from peripheral blood (PBMCs) and synovial fluid (SFMCs) of 20 PsA patients as well as from healthy donors were studied. Freshly isolated T and B cells from PBMCs and T cells and fibroblasts from SFMCs of PsA patients were subjected to RT-PCR to detect the levels of RANKL, TNFα, and IL-7. Osteoclastogenesis was studied in the presence of RANK-Fc, anti-TNFα, and anti IL-7 functional antibodies. We demonstrate that lymphocytes and fibroblasts support osteoclast (OC) formation in PsA patients through the production of osteoclastogenic cytokines. In particular, OC formation was completely abolished in unstimulated T cell-depleted PBMC cultures, and reduced by approximately 70% in unstimulated T cell-depleted SFMC cultures. Freshly isolated T cells from PBMCs and SFMCs of PsA patients overexpressed RANKL and TNFα, while fibroblasts from synovial fluid produced only RANKL. We show that the presence of RANK-Fc and/or anti-TNFα functional antibodies reduced OC formation. Moreover, T and B cells from PBMCs as well as T cells and fibroblasts from SFMCs expressed IL-7 mRNA. Finally, the anti-IL-7 functional antibody significantly reduced osteoclastogenesis. Our results suggest that fibroblasts, B and T lymphocytes support OC formation by producing RANKL, TNFα, and IL-7, contributing to the aggressive bone resorption in PsA patients. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background: Periodontitis is characterized by alveolar bone destruction; however, the mechanisms responsible for bone damage are poorly understood. It has been reported that T cells are implicated in the pathogenesis of periodontitis. It has been also demonstrated that activated T lymphocytes secrete receptor activator of nuclear factor-kappa B ligand (RANKL) and can support the differentiation of monocytes into resorbing osteoclasts (OCs). Therefore, the purpose of this study was to examine the OC formation in periodontitis patients (PP) and the role of T cells in osteoclastogenesis. Methods: To study OC formation, we used an in vitro model consisting of unstimulated and unfractionated peripheral blood mononuclear cells (PBMCs) from PP and controls. In parallel, T-cell-depleted PBMCs from the same patients were also established. The expression of RANKL and tumor necrosis factor-alpha (TNF-α) was analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot in fresh T cells isolated from PP and controls. Functional antibodies, anti-RANKL and anti-TNF-alpha;, were utilized to study osteoclastogenesis in PBMC cultures from PP. Results: We showed that, in unfractionated PBMCs from PP, the OCs spontaneously developed in a T-cell-dependent way. The addition of macrophage colony stimulating factor (MCSF) and RANKL was necessary to promote the osteoclastogenesis in T-cell-depleted PBMC cultures from PP and in unfractionated PBMCs from periodontally healthy controls. Moreover, freshly isolated T cells from PBMCs of PP overexpressed RANKL and TNF-α. Finally, functional anti-RANKL and anti-TNF-α antibodies significantly inhibited osteoclastogenesis. Conclusion: Our data suggest that T cells support spontaneous osteoclastogenesis in PP via RANKL and TNF-α overexpression. [ABSTRACT FROM AUTHOR]

Owing to the satisfactory esthetic and functional outcomes of implant surgery for the anterior teeth, some dentists consider it the gold standard treatment. However, the risk of developing peri-implantitis is positively associated with the long-term use of the implant. This necessitates the development of an implant design that reduces the risk of peri-implantitis, especially considering the long-term use of implants in young patients. This case report describes a new approach for an implant surgery using a two-stage implant in a 28-year-old woman. Her clinical course was satisfactory during the 4-year postoperative follow-up period; no inflammation was noted in the surrounding tissues. The two-stage implants allow for the removal of an implant body from an infected area and its replacement with a new abutment if peri-implantitis develops in the future., (© 2021 by the American College of Prosthodontists.)

Full-arch screw-retained implant-supported fixed dental prostheses have a high long-term success rate and are considered the gold standard by many clinicians. However, accurate fabrication of a passive fit long-span prosthesis can be challenging. A novel intraoral adhesion method using galvano-telescopic copings was proposed as a way of improving prosthetic fit for edentulous patients. This report describes the treatment of a 74-year-old female with a full-arch implant-supported dental prosthesis, supported by a combination of galvano-telescopic copings and screws to prevent retention loss. Four years have passed since this superstructure was placed, during this time she exhibited a good clinical course with no inflammation noted in surrounding tissues. Treatment with an implant-supported fixed dental prosthesis, retained by a combination of galvano-telescopic copings and screws, can be a useful alternative treatment for edentulous patients., (© 2019 by the American College of Prosthodontists.)

Inhibitors of the Mycobacterium tuberculosis enoyl-ACP reductase (InhA) are considered as potential promising therapeutics for the treatment of tuberculosis. Previously, we reported that azaisoindolinone-type compounds displayed, in vitro, inhibitory activity toward InhA. Herein, we describe chemical modifications of azaisoindolinone scaffold, the synthesis of 15 new compounds and their evaluations toward the in vitro InhA activity. Based on these results, a structure-InhA inhibitory activity relationship analysis and a molecular docking study, using the conformation of InhA found in the 2H7M crystal structure, were carried out to predict a possible mode of interaction of the best (aza)isoindolinone-type inhibitors with InhA in vitro. Then, the work was extended toward evaluations of these compounds against Mycobacterium tuberculosis (Mtb) growth, and finally, some of them were also investigated in respect of their ability to inhibit mycolic acid biosynthesis inside mycobacteria. Although, some azaisoindolinones were able to inhibit InhA activity and Mtb growth in vitro, they did not inhibit the mycolic acid biosynthesis inside Mtb., (© 2016 John Wiley & Sons A/S.)

The criterion of personal identity is clearly called into question by the project to perform a human head transplant. Is identity provided by psychological continuity alone, or does it depend on bodily continuity as well? And how do these different perspectives interface with our notion of mind and mind-body relationship? The reader will be provided with a discussion concerning these problems, together with a philosophical and literary survey about the conception of body-mind relationship from the Greek thought to contemporary philosophy. The analysis will conclude with a discussion concerning the possibility to consider the issue of personal identity from a statistic point of view, which privileges the general perception of identity, so as it has been shaped by the cultural trends of the last four centuries. It could hence be argued that personal identity is not something which can be defined once and for all. On the contrary, the general perception of identity is subject to significant alterations resulting from one's cultural environment. However, the cultural environment itself can be changed by particularly notable events, such as, hypothetically, the successful outcome of a human head transplant., (© 2016 John Wiley & Sons Ltd.)