Responsive coatings from naturally occurring pectin polysaccharides

Pectin polysaccharides have significant potential as all-natural, non-toxic "green" coatings that exhibit thermally-cued swelling behavior. Herein, ultra-thin coatings of highly-esterified pectin polysaccharides were cross-linked with calcium chloride (CaCl 2 ) and their swelling in water was investigated with ellipsometry. At low temperatures, the coatings swell to 2-3 times their dry layer thickness. As the temperature is increased, the coatings show a pronounced decrease in swollen thickness, reminiscent of the hydrophilic-hydrophobic transition observed in lower critical solution temperature (LCST) polymers. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy establishes that this transition is driven by dehydration of the esterified galacturonic acid residues along the pectin backbone. By adjusting both the CaCl 2 concentration used to crosslink the pectin coatings as well as pH of swelling medium, the pectin coatings could be judiciously tuned for a desired swelling response as a function of temperature. Due to their non-toxic and responsive nature, it was further demonstrated that such coatings could be used in applications to control cell adhesion.

Zeolite nanoparticles (H-ZSM5) as a highly efficient, green, and reusable heterogeneous catalyst for selective oxidation of sulfides to sulfoxides under mild conditions

Tribromide ion supported on boehmite nanoparticles as a reusable catalyst for organic reactions

Conserved SUN-KASH Interfaces Mediate LINC Complex-Dependent Nuclear Movement and Positioning

Many nuclear positioning events involve linker of nucleoskeleton and cytoskeleton (LINC) complexes, which transmit forces generated by the cytoskeleton across the nuclear envelope. LINC complexes are formed by trans-luminal interactions between inner nuclear membrane SUN proteins and outer nuclear membrane KASH proteins, but how these interactions are regulated is poorly understood. We combine in vivo C. elegans genetics, in vitro wounded fibroblast polarization, and in silico molecular dynamics simulations to elucidate mechanisms of LINC complexes. The extension of the KASH domain by a single alanine residue or the mutation of the conserved tyrosine at -7 completely blocked the nuclear migration function of C. elegans UNC-83. Analogous mutations at -7 of mouse nesprin-2 disrupted rearward nuclear movements in NIH 3T3 cells, but did not disrupt ANC-1 in nuclear anchorage. Furthermore, conserved cysteines predicted to form a disulfide bond between SUN and KASH proteins are important for the function of certain LINC complexes, and might promote a developmental switch between nuclear migration and nuclear anchorage. Mutations of conserved cysteines in SUN or KASH disrupted ANC-1-dependent nuclear anchorage in C. elegans and Nesprin-2G-dependent nuclear movements in polarizing fibroblasts. However, the SUN cysteine mutation did not disrupt nuclear migration. Moreover, molecular dynamics simulations showed that a disulfide bond is necessary for the maximal transmission of cytoskeleton-generated forces by LINC complexes in silico. Thus, we have demonstrated functions for SUN-KASH binding interfaces, including a predicted intermolecular disulfide bond, as mechanistic determinants of nuclear positioning that may represent targets for regulation.

Neuregulin1 types mRNA level changes in autism spectrum disorder, and is associated with deficit in executive functions

Autism spectrum disorder (ASD) is a pediatric heterogeneous psychiatric and neurodevelopmental disorder with social and communication deficits, language impairment and ritualistic or repetitive behaviors. ASD has significant genetic bases but candidate genes and molecular mechanisms of disorder are not clarified. Neuregulin1 (NRG1) gene, located in 8p12 is involved in development of central nervous system and was indicated as candidate gene in schizophrenia.

Evaluation of health-related quality of life and muscular strength in children with beta thalassemia major

Background: Thalassemia is an inherited blood disorder that requires repeated blood transfusions and chelation regimes. This may lead to restrictions in physical activities, social participation as well as decreased muscle strength. Aim: The aim of this study was to evaluate the health-related quality of life (HRQoL), muscular strength and pain in children with β-thalassemia major. Patients and method: One hundred and twenty children (60 with β -thalassemia major and 60 age-matched healthy) were participated in a cross-sectional study from both sexes (57 girls and 63 boys) with ages ranging from two to twelve years. HRQoL (physical, emotional, social and school functioning), muscular strength and pain were evaluated for all children by using the pediatric quality of life inventory TM (PedsQL TM ) 4.0 generic core scale, hand-held dynamometer and visual analogue scale (VAS) respectively. Results: Children with β-thalassemia major showed a significant decrease in all domains of health-related quality of life and handgrip strength with a significant increase in VAS score (p  ≤ 0.0001). Conclusions: The study concluded that thalassemia as a chronic disease has a negative impact on HRQoL and muscle strength of children in different age group. Keywords: Beta thalassemia, Quality of life, Handgrip strength, children

Mechanical LINCs of the nuclear envelope: Where SUN meets KASH

Author(s): Jahed, Z; Mofrad, MRK | Abstract: © 2018 Elsevier Ltd The transmission of mechanical signals across the nuclear envelope is primarily mediated by linkers of the nucleoskeleton and cytoskeleton (LINC complexes). These complexes bridge the inner and outer nuclear membrane and connect various elements of the cytoskeleton to the nucleoskeleton. Through their interaction with various cytoskeletal elements, LINC complexes repeatedly endure different types of mechanical loading. In this short review, we discuss the structural features of LINC complexes that allow them to withstand and transmit mechanical forces across the nuclear envelope, the types of mechanical forces on these complexes, and the consequences of these forces on the integrity of the nuclear envelope.

How do glutathione antioxidant enzymes and total antioxidant status respond to air pollution exposure?

This study aims to investigate how antioxidant enzyme activity and overall antioxidant capacity respond to short-term changes in exposure to air pollution. 201 participants were recruited before- and followed up during- and after- the 2008 Beijing Olympics. Serum levels of antioxidant enzymes including glutathione S-transferases (GST), glutathione peroxidase (GPx), glutathione reductase (GR), and total antioxidant status (TAS) were measured. We used linear mixed-effects models to compare changes in antioxidant enzymes across the three periods after adjusting for potential confounding factors. Among all participants, glutathione peroxidase (GPx) levels decreased by 12.0% when air pollution dropped by 50-60% during the Olympics and increased by 6.5% when air pollution levels rose after the Olympics. The magnitude of increase among males, smokers, and older individuals was relatively smaller compared to females, nonsmokers, and younger individuals. Among all participants, total antioxidant status (TAS) significantly decreased by 6.23% during the games and continued to decrease by 4.41% after the games. However, among females, nonsmokers, and younger participants, there was an increase in TAS response to the elevated air pollution levels. Our study observed strong responses in GPx and TAS levels to the short-term decrease and increase of air pollution levels and responses varied among subgroups.

afpCOOL: A tool for antifreeze protein prediction

Various cold-adapted organisms produce antifreeze proteins (AFPs), which prevent the freezing of cell fluids by inhibiting the growth of ice crystals. AFPs are currently being recognized in various organisms, living in extremely low temperatures. AFPs have several important applications in increasing freeze tolerance of plants, maintaining the tissue in frozen conditions and producing cold-hardy plants by applying transgenic technology. Substantial differences in the sequence and structure of the AFPs, pose a challenge for researchers to identify these proteins. In this paper, we proposed a novel method to identify AFPs, using supportive vector machine (SVM) by incorporating 4 types of features. Results of the two used benchmark datasets, revealed the strength of the proposed method in AFP prediction. According to the results of an independent test setup, our method outperformed the current state-of-the-art methods. In addition, the comparison results of the discrimination power of different feature types revealed that physicochemical descriptors are the most contributing features in AFP detection. This method has been implemented as a stand-alone tool, named afpCOOL, for various operating systems to predict AFPs with a user friendly graphical interface.

Ultrasonic assisted synthesis, crystallographic, spectroscopic studies and biological activity of three new Zn(II), Co(II) and Ni(II) thiosemicarbazone complexes as precursors for nano-metal oxides