The influence of structural gradients in large pore organosilica materials on the capabilities for hosting cellular communities

Cells exist in the so-called extracellular matrix (ECM) in their native state, and numerous future applications require reliable and potent ECM-mimics. A perspective, which goes beyond ECM emulation, is the design of a host-material with features which are not accessible in the biological portfolio. Such a feature would, for instance, be the creation of a structural or chemical gradient, and to explore how this special property influences the biological processes. First, we wanted to test if macroporous organosilica materials with appropriate surface modification can act as a host for the implementation of human cells like HeLa or LUHMES. It was possible to use a commercially available polymeric foam as a scaffold and coat it with a thiophenol-containing organosilica layer, followed by biofunctionalization with biotin using click chemistry and the subsequent coupling of streptavidin–fibronectin to it. More importantly, deformation of the scaffold allowed the generation of a permanent structural gradient. In this work, we show that the structural gradient has a tremendous influence on the capability of the described material for the accommodation of living cells. The introduction of a bi-directional gradient enabled the establishment of a cellular community comprising different cell types in spatially distinct regions of the material. An interesting perspective is to study communication between cell types or to create cellular communities, which can never exist in a natural environment.

Chemical and structural gradients in biofunctionalized organosilica–polymer nanocomposites control cell adhesion properties and open perspectives for artificial cellular community systems.     

2015 Evidence Analysis Library Systematic Review on Advanced Technology in Food Production

In the late 20th century, plant breeders began using molecular biology techniques such as recombinant DNA, also known as genetic engineering, along with traditional cross-breeding. Ten plant and one animal food have been approved for commercialization in the United States. Today, foods and ingredients from genetically engineered (GE) crops are present throughout the food supply, which has led to varying levels of acceptance. Much discussion exists among consumers and health professionals about the believability of statements made regarding benefits or risks of GE foods. The aim of this systematic review was to examine the evidence on the association of consumption of GE foods and ingredients derived from them on human health, specifically allergenicity, food safety, pesticide consumption, nutrient adequacy, inflammation, and antibiotic resistance. An expert panel conducted a systematic review on advanced technology in food production. The 30 developed questions focused on effects of human consumption of GE foods and the effects of human consumption of foods containing pesticide residues on human health. Primary research published from 1994 to 2014 were identified using PubMed and Agricultural Online Access databases. Additional studies were identified by searching references of review articles. Twenty-one studies met the inclusion criteria. Relevant research addressed five of 30 questions. Four questions focused on food allergenicity, the fifth on nutrient adequacy, and all received a Grade III (limited/weak) rating. No human studies addressed 25 questions on the consumption of foods produced using genetic engineering technologies on gene translocation, cancer, food safety, phenotype expression, inflammation and inflammatory markers, or antibiotic resistance. These questions received a Grade V (grade not assignable). Evidence from human studies did not reveal an association between adverse health effects and consumption of foods produced using genetic engineering technologies. Although the number of available human studies is small, they support that there are no clear adverse health effects—as they relate to allergenicity and nutrient adequacy—associated with consumption of GE foods. The present systematic review is aligned with a recent report by the National Academy of Sciences that included human and animal research.     

Systemic complement activation, lung injury, and products of lipid peroxidation.

Previously we have demonstrated that systemic activation of the complement system after intravenous injection of cobra venom factor (CVF) results in acute lung injury as reflected by increases in the vascular permeability of the lung as well as by morphologic evidence of damage to lung vascular endothelial cells. In using the vascular permeability of the lung as the reference, the current studies show a quantitative correlation between lung injury and the appearance in plasma of lipid peroxidation products (conjugated dienes) as well as increased concentrations of lactic dehydrogenase (LDH) and one of its isoenzymes (LDH-4). After injection of CVF, extracts of lungs also showed elevated levels of conjugated dienes, whereas no elevations were found in extracts of liver, kidney, and spleen. There was no evidence in CVF-injected rats of renal or hepatic injury as reflected by the lack of development of proteinuria and the failure to detect increased serum levels of liver-related enzymes. Other peroxidation products identified in plasma of CVF-injected rats involved hydroperoxides and fluorescent compounds with features of Schiff bases. Not surprisingly, malondialdehyde was not found to be a reliable plasma indicator of lipid peroxidation associated with oxygen radical-mediated lung vascular injury. In using a model of oxygen radical-independent lung injury induced by oleic acid, although large amounts of LDH and LDH-4 were found in the plasma, no increases in plasma levels of conjugated dienes were detected. In CVF-injected animals treated with interventions protective against lung injury (neutrophil depletion, catalase, hydroxyl radical scavengers, or iron chelators), there were striking reductions in the plasma levels of conjugated dienes, hydroperoxides, and fluorochromic products. Morphometric analysis of lung sections revealed that the protective interventions did not interfere with the accumulation of neutrophils in lung interstitial capillaries after systemic activation of complement. In vitro studies with phorbol-stimulated neutrophils failed to demonstrate appearance of conjugated dienes, suggesting that the dienes appearing in plasma of CVF-injected animals are not the result of autotoxic changes in neutrophils. The data presented in this paper suggest that acute lung injury mediated by oxygen radicals derived from phagocytic cells can be monitored by the appearance in plasma of products of lipid peroxidation.     

SP rTaTME: initial clinical experience with single-port robotic transanal total mesorectal excision (SP rTaTME)

Techniques in Coloproctology - The technical difficulty and steep learning curve of transanal total mesorectal excision (taTME) has limited widespread adoption. The single-port (SP) daVinci robot...     

Desmuslin, an intermediate filament protein that interacts with alpha -dystrobrevin and desmin

Dystrobrevin is a component of the dystrophin-associated protein complex and has been shown to interact directly with dystrophin, alpha1-syntrophin, and the sarcoglycan complex. The precise role of alpha-dystrobrevin in skeletal muscle has not yet been determined. To study alpha-dystrobrevin's function in skeletal muscle, we used the yeast two-hybrid approach to look for interacting proteins. Three overlapping clones were identified that encoded an intermediate filament protein we subsequently named desmuslin (DMN). Sequence analysis revealed that DMN has a short N-terminal domain, a conserved rod domain, and a long C-terminal domain, all common features of type 6 intermediate filament proteins. A positive interaction between DMN and alpha-dystrobrevin was confirmed with an in vitro coimmunoprecipitation assay. By Northern blot analysis, we find that DMN is expressed mainly in heart and skeletal muscle, although there is some expression in brain. Western blotting detected a 160-kDa protein in heart and skeletal muscle. Immunofluorescent microscopy localizes DMN in a stripe-like pattern in longitudinal sections and in a mosaic pattern in cross sections of skeletal muscle. Electron microscopic analysis shows DMN colocalized with desmin at the Z-lines. Subsequent coimmunoprecipitation experiments confirmed an interaction with desmin. Our findings suggest that DMN may serve as a direct linkage between the extracellular matrix and the Z-discs (through plectin) and may play an important role in maintaining muscle cell integrity.     

Pre-B acute lymphoblastic leukemia cells may induce T-cell anergy to alloantigen

Even if neoplastic cells express tumor associated antigens they still may fail to function as antigen presenting cells (APC) if they lack expression of one or more molecules critical for the induction of productive immunity. These cellular defects can be repaired by physiologic activation, transfection, or fusion of tumor cells with professional APC. Although such defects can be repaired, antitumor specific T cells may still fail to respond in vivo if they may have been tolerized. Here, human pre-B cell acute lymphoblastic leukemia (pre-B ALL) was used as a model to determine if primary human tumor cells can function as alloantigen presenting cells (alloAPC) or alternatively whether they induce anergy. In the present report, we show that pre-B cell ALL express alloantigen and adhesion molecules but uniformly lack B7-1 (CD80) and only a subset express B7-2 (CD86). Pre-B ALL cells are inefficient or ineffective alloAPC and those cases that lack expression of B7-1 and B7-2 also induce alloantigen specific T- cell unresponsiveness. Under these circumstances, T-cell unresponsiveness could be prevented by physiologic activation of tumor cells via CD40, cross-linking CD28, or signaling through the common gamma chain of the interleukin-2 receptor on T cells. Taken together, these results suggest that pre-B ALL may be incapable of inducing clinically significant T-cell-mediated antileukemia responses. This defect may be not only due to their inability to function as APC, but also due to their potential to induce tolerance. Attempts to induce clinically significant antitumor immune responses may then require not only mechanisms to repair the antigen presenting capacity of the tumor cells, but also reversal of tolerance.     

Association of Hospital Employee Satisfaction with Patient Safety and Satisfaction within Veterans Affairs Medical Centers

Background

Employee satisfaction is thought to impact performance. However, which aspects of employee satisfaction matter most is unknown. We utilized data from the Veterans Affairs Medical Centers(VAMC) via their Strategic Analytics for Improvement and Learning program to examine the association between organizational satisfaction as well as job-specific satisfaction with measures of patient safety, patient satisfaction, and hospital rating.

Synthesis and assembly of human small nuclear ribonucleoproteins generated by cell-free translation.

Cell-free translation of human poly(A)+ RNA was carried out to generate and analyze the protein constituents of small nuclear ribonucleoprotein (snRNP) particles. The snRNP proteins were identified by immunoprecipitation with sera from patients with systemic lupus erythematosus. Size fractionation of mRNA prior to translation revealed that these snBNP proteins are all encoded by separate messages. One of the proteins (the A protein, molecular weight 32,000) was seen to lose antigenicity upon RNase treatment either when extracted from cells or when generated in vitro. RNase treatment of immunoprecipitated snRNPs released the A protein in an electrophoretically pure form. Analysis of snRNPs translated in vitro revealed the presence of unassembled and assembled particles as determined by sucrose density gradient sedimentation. Post-translational assembly of snRNPs involving both RNA-protein binding (as revealed by A protein antigenicity) and associations of other snRNP proteins occurred in the in vitro system employed here. In addition, the presence of unassembled snRNP proteins permitted the determination of the precise antigen peptides recognized by Sm and RNP autoimmune sera. It was observed that Sm sera are capable of recognizing each of the eight snRNP proteins, whereas RNP sera recognize only two of the eight.     

Palmitate-TLR4 signaling regulates the histone demethylase,JMJD3, in macrophages and impairs diabetic wound healing

Chronic macrophage inflammation is a hallmark of type 2 diabetes (T2D) and linked to the development of secondary diabetic complications. T2D is characterized by excess concentrations of saturated fatty acids (SFA) that activate innate immune inflammatory responses, however, mechanism(s) by which SFAs control inflammation is unknown. Using monocyte-macrophages isolated from human blood and murine models, we demonstrate that palmitate (C16:0), the most abundant circulating SFA in T2D, increases expression of the histone demethylase, Jmjd3. Upregulation of Jmjd3 results in removal of the repressive histone methylation (H3K27me3) mark on NFκB-mediated inflammatory gene promoters driving macrophage-mediated inflammation. We identify that the effects of palmitate are fatty acid specific, as laurate (C12:0) does not regulate Jmjd3 and the associated inflammatory profile. Further, palmitate-induced Jmjd3 expression is controlled via TLR4/MyD88-dependent signaling mechanism, where genetic depletion of TLR4 (Tlr4^−/−) or MyD88 (MyD88^−/−) negated the palmitate-induced changes in Jmjd3 and downstream NFκB-induced inflammation. Pharmacological inhibition of Jmjd3 using a small molecule inhibitor (GSK-J4) reduced macrophage inflammation and improved diabetic wound healing. Together, we conclude that palmitate contributes to the chronic Jmjd3-mediated activation of macrophages in diabetic peripheral tissue and a histone demethylase inhibitor-based therapy may represent a novel treatment for nonhealing diabetic wounds.