Bioactivation of 3D Cell-Imprinted Polydimethylsiloxane Surfaces by Bone Protein Nanocoating for Bone Tissue Engineering

Physical and chemical parameters that mimic the physiological niche of the human body have an influence on stem cell fate by creating directional signals to cells. Micro/nano cell-patterned polydimethylsiloxane (PDMS) substrates, due to their ability to mimic the physiological niche, have been widely used in surface modification. Integration of other factors such as the biochemical coating on the surface can achieve more similar microenvironmental conditions and promote stem cell differentiation to the target cell line. Herein, we investigated the effect of physical topography, chemical functionalization by acid bone lysate (ABL) nanocoating, and the combined functionalization of the bone proteins' nanocoated surface and the topographically modified surface. We prepared four distinguishing surfaces: plain PDMS, physically modified PDMS by 3D cell topography patterning, chemically modified PDMS with bone protein nanocoating, and chemically modified nano 3D cell-imprinted PDMS by bone proteins (ABL). Characterization of extracted ABL was carried out by Bradford staining and sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis, followed by the MTT assay for evaluation of cell viability on ABL-coated PDMS. Moreover, field emission scanning electron microscopy and profilometry were used for the determination of optimal coating thickness, and the appropriate coating concentration was identified and used in the study. The binding and retention of ABL to PDMS were confirmed by Fourier transform infrared spectroscopy and bicinchoninic acid assay. Sessile drop static water contact angle measurements on substrates showed that the combined chemical functionalization and nano 3D cell-imprinting on the PDMS surface improved surface wettability by 66% compared to plain PDMS. The results of ALP measurement, alizarin red S staining, immunofluorescence staining, and real-time PCR showed that the nano 3D cell-imprinted PDMS surface functionalized by extracted bone proteins, ABL, is able to guide the fate of adipose derived stem cellss toward osteogenic differentiation. Eventually, chemical modification of the cell-imprinted PDMS substrate by bone protein extraction not only improved the cell adhesion and proliferation but also contributed to the topographical effect itself and caused a significant synergistic influence on the process of osteogenic differentiation

Golpayegan metamorphic complex (Sanandaj–Sirjan Zone, Iran) as evidence for Cadomian back-arc magmatism: structure, geochemistry and isotopic data

The Golpayegan metamorphic complex is located in the Sanandaj-Sirjan Zone, Iran. This complex consists of various metamorphic rocks including schists, marbles, slates, gneisses, and amphibolites, most of them have Neoproterozoic age. The presence of structures such as sigma fabrics, boudinage, folded boudinage and interfering fold patterns indicates the occurrence of more than two deformation phases in the Golpayegan metamorphic complex. The measurement of strain intensity in the folds indicated deep immersion of structures and old Precambrian settings that had been influenced by orogenic events in the Neoproterozoic. These deformed rocks were exposed during extensional movements and, subsequently, sheared. The results based on field works shown geochemical relations and initial εNd(600 Ma) values of amphibolites in three sampling points located in Golpayegan region manifested that the protolith of the first (a') and second (b') sampling points had mantle origin (ortho-amphibolite), whilst protolith of the third (c') sampling point had sedimentary origin (para-amphibolite). Geochemically, the Golpayegan ortho-amphibolites showed subalkaline basalt-basaltic andesite compositions of tholeiitic affinity. The negative anomalies of Nb and Ti relative to Pb, La, and Ce in the primitive mantle-normalized spider-diagram and εNd(600 Ma) values revealed the subduction environment for ortho-amphibolites. The ortho-amphibolites exhibited the intermediate chemistry between the normal mid-ocean ridge basalt and island-arc tholeiitic basalt. Enrichment in large ion lithophile elements (LILE), light rare earth elements (LREE), and relative depletion in high field strength elements (HFSE) suggest the back-arc basin setting for the Golpayegan ortho-amphibolites. The primitive magma of the ortho-amphibolites was produced by 8–20% melting of spinel lherzolite. According to the Neoproterozoic age of the Golpayegan ortho-amphibolites and their relationship with the Golpayegan granitic gneiss (596‒578 Ma), it shows that they can be related to the Cadomian back-arc basin in the north of Peri-Gondwana at the Neoproterozoic. The high values of 87Sr/86Sr (0.708450‒0.714986) interpreted as result of seawater hydrothermal alteration.publishe

Having to manage : culturally and linguistically diverse mothers' lived experiences with sustained nurse home visiting programs

Background: Culturally and linguistically diverse (CALD) mothers with young children with limited English proficiency (LEP) encounter multiple barriers in accessing and engaging with primary healthcare services. The aim of this study was to explore the lived experiences and perceptions of CALD mothers with LEP in receiving child and family health nursing (CFHN) services and sustained nurse home visiting (SNHV) programs. Methods: Fourteen mothers were interviewed from two large Local Health Districts in Sydney. All interviews were audio-recorded for transcription purposes. Interpretative Phenomenology Analysis (IPA) was used for analysis and the socioecological approach was applied to interpret the data. Results: CALD mothers with LEP experienced both challenges and facilitators in their access and engagement with CFHN services and SNHV programs that were identified in four themes: managing culture; managing the service system; managing the relationship; and strengths and weaknesses of CFHN services. Conclusion: The integration of strategies such as building trusting relationships, using female professional interpreters and better understanding of CALD mothers’ cultural practices may address CALD mothers’ needs and facilitate communication. Design and development of model of support involving CALD mothers with LEP in ways that voice their ideas could meet their needs and contribute to better engagement of this vulnerable population with CFHN services and SNHV programs

Biological Evaluation of a Novel Tissue Engineering Scaffold of Layered Double Hydroxides (LDHs)

Bone Tissue Engineering (BTE) Composed of Three Main Parts: Scaffold, Cells and Signaling Factors. Several Materials and Composites Are Suggested as a Scaffold for BTE. Biocompatibility is One of the Most Important Property of a BTE Scaffold. in This Work Synthesis of a Novel Nanocomposite Including Layered Double Hydroxides (LDH) and Gelatin is Carried Out and its Biological Properties Were Studied. the Co-Precipitation (PH=11) Method Was Used to Prepare the LDH Powder, using Calcium Nitrate, Magesium Nitrate and Aluminum Nitrate Salts as Starting Materials. the Resulted Precipitates Were Dried. X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) Analyses Were Used to Characterize the Synthesized Powders. the Results Demonstrated the Presence of Nanocrystals of Ca-LDH and Mg-LDH as Hexagonal and Layered Morphology. the Obtained Powders Were Composed to Gelatin Via Solvent Casting Method Then Freez Dried. the Scaffold Was Prepared Via Membrane Lamination Method from the Resulted Layers that Linked Together with Gelatin as Binder. in Order to Investigate the Scaffold Cytotoxicity MTT Assay Was Done with a Osteosarcoma Cell Line. No Toxic Response Was Observed in Specimens. as a Major Result, It Was Demonstrated that the Specimen Showed a Significant Cellular Response. Then Osteosarcoma Cells Were Cultured for 7-Day and 14-Day Extract of Powders. the Composites Osteoconductivity Was Investigate with Cells Alkaline Phosphatase Extraction. the Results Demonstrated that the Ca-LDH/gelatin Composite Scaffold Has a Good Potential for Bone Tissue Engineering Applications and Mg-LDH Specimen Has a Better Osteconductivity. © (2012) Trans Tech Publications

Interpreter use in sustained nurse home visiting : interpreter experience and support

Background: The aim of this study was to explore the experiences of healthcare interpreters working with child and family health nurses (CFHNs) in providing child and family health nursing (CFHN) services and sustained nurse home visiting (SNHV) programs to culturally and linguistically diverse (CALD) families with limited English proficiency. Methods: A mixed methods longitudinal research design was conducted to develop, implement and evaluate a training and practice support model for healthcare interpreters working with nurses and CALD families in providing CFHN services and SNHV programs in three major local health services in Sydney, Australia. One pre-training survey with 24 healthcare interpreters was conducted; field notes were recorded during training and implementation; and a post-implementation focus group with six healthcare interpreters was conducted. Quantitative survey data were analysed descriptively using Alchemer. The focus group was audio-recorded for transcription purposes, and this and the field notes were thematically analysed applying a socioecological framework. Results: Three themes were identified from the initial, pre-training survey: facilitate communication and delivery accurately; a bridge linking the clients and the healthcare practitioners; and make everybody feel comfortable. Practice support implementation was negatively impact by system and COVID-19 related barriers. Four themes were developed from evaluative phase of the study including: system-related issues; interpreters’ challenges; working with nurses; and client session related issues. Conclusion: Quality interpreting was favourably influenced by adequate time for interpreting the session including a pre- and post-briefing session with CFHNs, an appropriate mode of interpretation, allocation of female interpreters and the same interpreters with CALD mothers and clarity about interpreter role and cultural comfort. These strategies support the quality of communication and relationships in delivery of CFHN services and SNHV programs to CALD mothers with limited English proficiency

Jamming during particle spreading in additive manufacturing

Additive manufacturing (AM) is going through an exponential growth, due to its enormous potential for rapid manufacturing of complex shapes. One of the manufacturing methods is based on powder processing, but its major bottleneck is associated with powder spreading, as mechanical arching adversely affects both product quality and speed of production. Here we analyse transient jamming of gas-atomised metal powders during spreading. These particles are highly frictional, as they have asperities and multiple spheres and are prone to jamming in narrow gaps. Therefore their detailed characterisations of mechanical properties are critical to be able to reliably predict the jamming frequency as influenced by powder properties and process conditions. Special methods have been used to determine the physical and mechanical properties of gas-atomised stainless steel powders. These properties are then used in numerical simulations of powder spreading by the Discrete Element Method. Particle shape is reconstructed for the simulations as a function of particle size. The characteristic size D₉₀ by number (i.e. the particle size, based on the projected-area diameter, for which 90% of particles by number are smaller than this value) is used as the particle dimension accountable for jamming. Jamming is manifested by empty patches over the work surface. Its frequency and period have been characterised as a function of the spreader gap height, expressed as multiple of D₉₀. The probability of formation of empty patches and their mean length, the latter indicating jamming duration, increase sharply with the decrease of the gap height. The collapse of the mechanical arches leads to particle bursts after the blade. The frequency of jamming for a given survival time decreases exponentially as the survival time increases

A patient with sick sinus syndrome, atrial flutter and bidirectional ventricular tachycardia: Coincident or concomitant presentations?

Channelopathies are among the major causes of syncope or sudden cardiac death in patients with structurally normal hearts. In these patients, the atrium, ventricle or both could be affected and reveal different presentations. In this case, we present a patient with an apparently structurally normal heart and recurrent syncope, presented as sick sinus syndrome with atrial flutter and bidirectional ventricular tachycardia. Copyright © 2007 Via Medica

Early septal activation, successful lateral ablation

The coronary sinus activation pattern is an important clue for the detection of arrhythmia mechanisms and/or localization of accessory pathways. Any change in this pattern during radiofrequency ablation should be evaluated carefully to recognize the presence of another accessory pathway or innocence of the accessory pathway during arrhythmia. Intra-atrial conduction block can change the coronary sinus activation pattern. Negligence regarding this phenomenon can cause irreversible complications. Here we describe a case with left lateral accessory pathway conduction in which intra-atrial conduction block completely reversed the coronary sinus activation pattern. Copyright © 2008 Via Medica

Genetic Analysis of Human Traits In Vitro: Drug Response and Gene Expression in Lymphoblastoid Cell Lines

Lymphoblastoid cell lines (LCLs), originally collected as renewable sources of DNA, are now being used as a model system to study genotype–phenotype relationships in human cells, including searches for QTLs influencing levels of individual mRNAs and responses to drugs and radiation. In the course of attempting to map genes for drug response using 269 LCLs from the International HapMap Project, we evaluated the extent to which biological noise and non-genetic confounders contribute to trait variability in LCLs. While drug responses could be technically well measured on a given day, we observed significant day-to-day variability and substantial correlation to non-genetic confounders, such as baseline growth rates and metabolic state in culture. After correcting for these confounders, we were unable to detect any QTLs with genome-wide significance for drug response. A much higher proportion of variance in mRNA levels may be attributed to non-genetic factors (intra-individual variance—i.e., biological noise, levels of the EBV virus used to transform the cells, ATP levels) than to detectable eQTLs. Finally, in an attempt to improve power, we focused analysis on those genes that had both detectable eQTLs and correlation to drug response; we were unable to detect evidence that eQTL SNPs are convincingly associated with drug response in the model. While LCLs are a promising model for pharmacogenetic experiments, biological noise and in vitro artifacts may reduce power and have the potential to create spurious association due to confounding.Molecular and Cellular Biolog