Basement Membrane Zone Collagens XV and XVIII/Proteoglycans Mediate Leukocyte Influx in Renal Ischemia/Reperfusion

Collagen type XV and XVIII are proteoglycans found in the basement membrane zones of endothelial and epithelial cells, and known for their cryptic anti-angiogenic domains named restin and endostatin, respectively. Mutations or deletions of these collagens are associated with eye, muscle and microvessel phenotypes. We now describe a novel role for these collagens, namely a supportive role in leukocyte recruitment. We subjected mice deficient in collagen XV or collagen XVIII, and their compound mutant, as well as the wild-type control mice to bilateral renal ischemia/reperfusion, and evaluated renal function, tubular injury, and neutrophil and macrophage influx at different time points after ischemia/reperfusion. Five days after ischemia/reperfusion, the collagen XV, collagen XVIII and the compound mutant mice showed diminished serum urea levels compared to wild-type mice (all

Electrochemical effects of silane pretreatments containing cerium nitrate on cathodic disbonding properties of epoxy coated steel

Published online: 27 Mar 2013.In the recent years, silane materials, because of their environmental friendly nature and ease of application have been attended as an alternative for chromate conversion coatings. Different materials were searched for improvement of the efficiency of silane formulation. In this research, pretreatment of carbon steel substrates was carried out using γ-glycidoxypropyl-trimethoxysilane (γ-GPS) as functionalized silane. Cerium nitrate as a corrosion inhibitor material was introduced into the silane material and epoxy resin was applied on the pretreated steel substrates. Effects of the pretreatment on electrochemical properties, cathodic disbondment, dry and wet adhesion strength, and surface morphology of resultant epoxy coating were investigated. Results showed that pretreatment of steel substrate with γglycidoxypropyl-trimethoxysilane (γ-GPS) doped with cerium nitrate leads to improvement of cathodic disbondment and also dry and wet adhesion of epoxy coating. Furthermore, this type of pretreatment reduced the disruption of interfacial bonds at the binder/substrate interface. Addition of 2 wt% cerium nitrate into the silane formulation led to the maximum efficiency of resultant coating.Sadeq Hooshmand Zaferania, Mahmood Peikaria, Davood Zaareib and Iman Danaei

Using silane films to produce an alternative for chromate conversion coatings

Preprint available online: October 17, 2012Recently, many efforts have been made to find environmentally friendly substitutes for carcinogen Cr⁶⁺ in the pretreatments of metal substrates. Silane films are one of the important candidates for this purpose. The use of silane films on metallic substrates provides corrosion protection as a result of excellent adhesion and good barrier properties. Their corrosion protection can be improved by adding suitable dopants. There are various methods for applying these films on the metal substrates (sol-gel dip coatings and electrodeposited coating). In this review, several main researches in the field of silane films have been indicated and their results have been analyzed.S.H. Zaferani, M. Peikari, D. Zaarei, I. Danaee, J.M. Fakhraei, and M. Mohammad

A Deep Neural Network Combined with Radial Basis Function for Abnormality Classification

Researchers working on cancer datasets often encounter two major challenges in their data science tasks. First, the numbers of samples are often low while the numbers of features needed for extraction are high. Secondly, the existence of noise and uncertainties in datasets can cause issues with any data science related tasks. Addressing such issues is of paramount importance to researchers and consequently to society as well. In this paper, making use of Principal Component Analysis (PCA) we remove irrelevant and redundant features from known cancer datasets. We then implement a novel internal structure using a deep neural network, which is based on the radial basis function (RBF) for feature extraction. This task is followed with the selection of the most informative features, which are prepared for an adaptive neuro-fuzzy inference system (ANFIS) based on Takagi-Sugeno-Kang (TSK). The entire process considers different values of thresholds which may cause a deficient number of features for classification. As a result, in the fuzzy classifier, the number of rules will not be substantial. Finally, our proposed approach is evaluated in three cancer datasets which are COLON, ALL-AML, and LEUKEMIA. We also apply two classifiers: 1) neuro-fuzzy inference system with different types of membership functions and 2) multi-layer perceptron to classify those cancer datasets into two groups. Our strong experimental results show that our method leads to a higher accuracy when compared to a multi-layer perceptron classifier

Hydrogels Based on Cellulose and its Derivatives: Applications, Synthesis, and Characteristics

Hydrogels are mainly structures formed from biopolymers and/or polyelectrolytes, and contain large amounts of trapped water. Smart cellulose-based superabsorbent hydrogels are the new generation of scaffold which fabricated directly from native cellulose (including bacterial cellulose) via cellulose dissolution. Cellulose has many hydroxyl groups and can be used to prepare hydrogels with fascinating structures and properties. Cellulose hydrogels based on its derivatives, including methyl cellulose (MC), hydroxypropyl cellulose (HPC), hydroxypropylmethyl cellulose (HPMC), and carboxymethyl cellulose (CMC) can be fabricated by various methods. On the basis of the cross-linking method, the hydrogels can be divided into chemical and physical gels. Physical gels are formed by molecular self-assembly through ionic or hydrogen bonds, while chemical gels are formed by covalent bonds. Composite smart hydrogels are prepared using cellulose in conjunction with other polymers through blending, formation of polyelectrolyte complexes, and interpenetrating polymer networks (IPNs) technology. According to type of superabsorbent cellulose-based hydrogels fabrication methods, there are many various techniques to evaluate quality of them. Briefly, some of these means generally used to assess the hydrogel are described as following. The obtained gel membranes are characterized by infrared spectroscopy, scanning electron microscopy, thermo gravimetric analysis, and mechanical tests in order to investigate the crosslinking occurrence and modifications of cellulose resulting from the synthetic process, morphology of the hydrogels, their thermal stability, and viscoelastic extensional properties, respectively. This review highlights the recent progress in smart cellulose-based superabsorbent hydrogel designs, fabrication approaches and characterization methods, leading to the development of cellulose based smart superabsorbent hydrogels

Reduced macrophage/monocyte influx after renal I/R in double mutant mice for collagen XV and XVIII.

<p><i>A:</i> Immunofluorescent staining for collagen IV, XV and XVIII (green) and macrophages (red) in WT and double mutant mice at day 5 after I/R showed presence of collagen IV, XV and XVIII in peritubular capillaries (white arrows) in WT mice and accumulation of macrophage/monocytes around these capillaries. Less macrophage influx (in red) was observed in double mutant mice, also lacking collagen XV and XVIII signal (in green). The nuclei are stained in blue. Scale bars 20 µm. <i>B:</i> Immunofluorescent staining for macrophages (red) and nuclei (blue) in WT and double mutant sham operated mice at day 5 after I/R showed no macrophage/monocyte in renal tissues. Scale bars 20 µm. <i>C:</i> Number of macrophage/monocytes per HPF (High Power Field) at different timepoints after I/R. At day 5 significantly less macrophage/monocytes were observed in kidneys of <i>Col15a1^−/−×Col18a1^−/−</i> mice compared to WT (p<0.05). Data is presented as mean ± SEM. *: p<0.05.</p

MCP-1-induced monocyte migration is increased in the presence of immobilized heparin-albumin and glycosylated collagen XVIII.

<p><i>A:</i> MCP-1 dose dependently increased the migration of monocytes over a porous membrane. Immobilization of heparin-albumin, mimicking an artificial BM HSPG, promotes monocyte transmigration. Spontaneous migration over albumin-coated membrane in the absence of MCP-1 was set as 1 and the other values were calculated accordingly. The error bars represent SEM. <i>B:</i> Transmigration of monocytes towards MCP-1 (10 ng/ml) was increased in the presence of heparin-albumin and collagen XVIII with long GAG chains. Heparin-albumin increased the monocyte migration significantly compared to albumin coated membrane (p<0.01). N-terminal fragment of short collagen XVIII with long GAG chains promoted transmigration significantly compared to albumin and N-terminal fragment without GAG chain (both p<0.05). Relative to albumin, also the full-length short collagen XVIII promoted MCP-1-induced monocyte transmigration to some extent (not significant). Data is calculated relative to migration over albumin-coated membrane towards 10 ng/ml MCP-1. The error bars represent SEM. *: p<0.05, **: p<0.01.</p