Self-Assembly of Homo Phenylalanine Oligopeptides: Role of Oligopeptide Chain Length.

The self-assembly of phenylalanine (F)-based peptides is a critical area of research with potential implications for the development of advanced biomaterials and technologies. Previous studies indicate that homo-oligopeptides with F-X residues (X = 1 to 6) can self-assemble into diverse nano-microstructures, but the role of oligopeptide chain length on this process remains unclear. This review investigates the role of F-X chain length on self-assembly processes and morphologies, considering the effect of incubation conditions and the capping group at the N and/or C terminals.

Evaluation of lipid profile, liver function enzymes, and trace elements in Iraqi diabetic nephropathy patients.

Diabetic nephropathy, a common complication of type 2 diabetes (T2DM), is associated with abnormal lipid profiles, liver dysfunction, and kidney impairment. However, research on its association with trace elements in Iraqi patients is limited. The objective of the present study is to evaluate the association between lipid profile, liver function, and trace elements in diabetic nephropathy (DN) patients.

Evaluation of Heavy Metal and Specific Trace Elements Levels Among Fast-Food Workers and Their Susceptibility to Atherosclerosis.

Fast-food workers in Iraq face significant health risks due to exposure to heavy metals from fumes and dust during cooking activities. Heavy metals, such as lead (Pb), cadmium (Cd), and nickel (Ni), are toxic to cells even at low concentrations and can cause health risks, including atherosclerosis, due to oxidative stress and reduced antioxidant activity. To the best of our knowledge, this is the first study assess the levels of heavy metals in fast-food workers and investigate their potential link to atherosclerosis development by monitoring the levels of copper (Cu), zinc (Zn), magnesium (Mg), manganese (Mn), and iron (Fe).

A comparative study of serum Zn, Cu, Mg, Mn, Cr, and Fe levels and their association with the vulnerability of Iraqi COVID-19 patients.

Background: For the immune system to protect the body from infectious diseases such as COVID-19, it needs the ideal amount of vital trace elements. Trace element levels, especially, zinc (Zn), copper (Cu), magnesium (Mg), manganese (Mn), chromium (Cr), and iron (Fe) levels, may affect how sensitive an individual is to COVID-19 and other viruses. The current study evaluated the level of those trace elements during stays in the isolation center and investigated their association with vulnerability to COVID-19.

Current status of structural studies of proteins originating from Arachnida.

Arthropods from class Arachnida constitute a large and diverse group with over 100,000 described species, and they are sources of many proteins that have a direct impact on human health. Despite the importance of Arachnida, few proteins originating from these organisms have been characterized in terms of their structure. Here we present a detailed analysis of Arachnida proteins that have their experimental structures determined and deposited to the Protein Data Bank (PDB).

Material Properties and Cell Compatibility of Photo-Crosslinked Sericin Urethane Methacryloyl Hydrogel.

There is a need to develop novel cytocompatible hydrogels for cell encapsulation and delivery in regenerative medicine. The objective of this work was to synthesize isocyanato ethyl methacryloyl-functionalized sericin and determine its material properties as a natural hydrogel for the encapsulation and delivery of human mesenchymal stem cells (MSCs) in regenerative medicine. Sericin extracted from silk cocoons was reacted with 2-isocyanatoethyl methacrylate (IEM) or methacrylic anhydride (MA) to produce sericin urethane methacryloyl (SerAte-UM) or sericin methacryloyl (SerAte-M, control) biopolymers, respectively.

Material properties and cell compatibility of poly(γ-glutamic acid)-keratin hydrogels.

Given the great demand for biopolymer and protein-based products from renewable resources, synthesis of a keratin-based hydrogel is presented herein. In this work, a novel hydrogel of poly(γ-glutamic acid) (γ-PGA) and keratin was synthesized through facile EDC·HCl/HOBt chemistry. Since keratin main chain is rich in amino side groups, carboxyl groups in γ-PGA were crosslinked with multi terminated amine groups in keratin.

Plasmin-Cleavable Nanoparticles for On-Demand Release of Morphogens in Vascularized Osteogenesis.

The objective of this work was to engineer self-assembled nanoparticles (NPs) for on-demand release of bone morphogenetic protein-2 (BMP2) and vascular endothelial growth factor (VEGF) in response to enzymes secreted by the migrating human mesenchymal stem cells (hMSCs) and human endothelial colony forming cells (ECFCs) to induce osteogenesis and vasculogenesis. Gene expression profiling experiments revealed that hMSCs and ECFCs, encapsulated in osteogenic/vasculogenic hydrogels, expressed considerable levels of plasminogen, urokinase plasminogen activator and its receptor uPAR, and tissue plasminogen activator. Therefore, the plasmin-cleavable lysine-phenylalanine-lysine-threonine (KFKT) was used to generate enzymatically cleavable NPs.

Development of microparticles for controlled release of resveratrol to adipose tissue and the impact of drug loading on particle morphology and drug release.

Resveratrol is a small molecule produced by various plants with a remarkable range of beneficial functions in animals. One of these is stimulating signaling pathways in adipose tissue that protect against obesity. Unfortunately, resveratrol suffers from poor bioavailability that inhibits its accumulation in target tissues, including fat, thus hindering the realization of its therapeutic potential.

Material and regenerative properties of an osteon-mimetic cortical bone-like scaffold.

The objective of this work was to fabricate a rigid, resorbable and osteoconductive scaffold by mimicking the hierarchical structure of the cortical bone. Aligned peptide-functionalize nanofiber microsheets were generated with calcium phosphate (CaP) content similar to that of the natural cortical bone. Next, the CaP-rich fibrous microsheets were wrapped around a microneedle to form a laminated microtube mimicking the structure of an osteon.

Regenerative Scar-Free Skin Wound Healing.

Millions of people every year develop scars in response to skin injuries after surgery, trauma, or burns with significant undesired physical and psychological effects. This review provides an update on engineering strategies for scar-free wound healing and discusses the role of different cell types, growth factors, cytokines, and extracellular components in regenerative wound healing. The use of pro-regenerative matrices combined with engineered cells with less intrinsic potential for fibrogenesis is a promising strategy for achieving scar-free skin tissue regeneration.

Sequential Zonal Chondrogenic Differentiation of Mesenchymal Stem Cells in Cartilage Matrices.

The higher regenerative capacity of fetal articular cartilage compared with the adult is rooted in differences in cell density and matrix composition. We hypothesized that the zonal organization of articular cartilage can be engineered by encapsulation of mesenchymal stem cells in a single superficial zone-like matrix followed by sequential addition of zone-specific growth factors within the matrix, similar to the process of fetal cartilage development. The results demonstrate that the zonal organization of articular cartilage can potentially be regenerated using an injectable, monolayer cell-laden hydrogel with sequential release of growth factors.

Devitalized Stem Cell Microsheets for Sustainable Release of Osteogenic and Vasculogenic Growth Factors and Regulation of Anti-Inflammatory Immune Response.

The objective of this work was to investigate the effect of devitalized human mesenchymal stem cells (hMSCs) and endothelial colony-forming cells (ECFCs) seeded on mineralized nanofiber microsheets on protein release, osteogenesis, vasculogenesis, and macrophage polarization. Calcium phosphate nanocrystals were grown on the surface of aligned, functionalized nanofiber microsheets. The microsheets were seeded with hMSCs, ECFCs, or a mixture of hMSCs+ECFCs, cultured for cell attachment, differentiated to the osteogenic or vasculogenic lineage, and devitalized by lyophilization.

Synthesis and Characterization of Photo-Cross-Linkable Keratin Hydrogels for Stem Cell Encapsulation.

The objective of this work was to synthesize an injectable and photopolymerizable hydrogel based on keratin extracted from poultry feather for encapsulation and delivery of stem cells in tissue regeneration. Since feather keratin is rich in cysteine residue, allylation of sulfhydryl groups was used for functionalization of keratin. Keratin was extracted from feather barbs by reducing the disulfide bonds in cysteine residues to sulfhydryl groups (-SH).