Feed Restriction Modulates Growth,Gut Morphology and Gene Expression in Zebrafish

A reduction in daily caloric or nutrient intake has been observed to promote health benefits in mammals and other vertebrates. Feed Restriction (FR), whereby the overall food intake of the organism is reduced, has been explored as a method to improve metabolic and immune health, as well as to optimize productivity in farming. However, less is known regarding the molecular and physiological consequences of FR. Using the model organism, Danio rerio, we investigated the impact of a short-term (month-long) FR on growth, gut morphology and gene expression. Our data suggest that FR has minimal effects on the average growth rates, but it may affect weight and size heterogeneity in a sex-dependent manner. In the gut, we observed a significant reduction in gut circumference and generally lower mucosal heights, whereas other parameters remained unchanged. Gene Ontology (GO), EuKaryotic Orthologous Groups (KOG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis identified numerous metabolic, reproductive, and immune response pathways that were affected by FR. These results broaden our understanding of FR and contribute towards growing knowledge of its effects on vertebrate health.     

Absolute quantitation of beta-lactoglobulin by protein liquid chromatography-mass spectrometry and its application to different milk products

The absolute quantitation of proteins in biological matrixes is of great interest in many fields and can be accomplished by different methodologies. Here, a method for the absolute quantitation of the whey protein beta-lactoglobulin using protein liquid chromatography coupled to mass spectrometry is reported. The developed approach was characterized in detail and applied to the determination of beta-lactoglobulin contents in various milk products. A special focus was placed on the recovery rates of the isolation procedure and on robust quantitation by LC-MS. For these purposes protein internal standards were employed. The observed recovery rates of beta-lactoglobulin from various samples ranged from 100% for whole milk to just over 50% for a strongly processed yogurt-based baby food product. The influence of processing was investigated in greater detail, showing that an increasing intensity of the applied heat treatment resulted in an increasing loss of beta-lactoglobulin. LC-MS quantitation at the protein level proved to be highly suitable, avoiding a potentially problematic digestion step. The use of an appropriate internal standard to compensate for sample losses during sample workup was shown to be essential for obtaining accurate results.     

Biocompatible porous ceramics for the cultivation of hematopoietic cells

Porous ceramics made of alumina and hydroxyapatite were created using a protein foaming method. Porosity and pore size distribution were successfully varied by means of chemical modification of the foaming protein Bovine serum albumin (BSA). The effectiveness of the BSA and of its chemical modifications as well as the influence of the dispersing agent were investigated using synchrotron tomography. Resulting porous ceramic materials were used as three-dimensional substrates for the cultivation of human peripheral stem cells. The cells proliferated and differentiated in culture. Five cell lines consistent with human blood cell lines were observed.     

Synthetic MUC1 Antitumor Vaccine with Incorporated 2,3‐Sialyl‐T Carbohydrate Antigen Inducing Strong Immune Responses with Isotype Specificity

The endothelial glycoprotein MUC1 is known to underlie alterations in cancer by means of aberrant glycosylation accompanied by changes in morphology. The heavily shortened glycans induce a collapse of the peptide backbone and enable accessibility of the latter to immune cells, rendering it a tumor‐associated antigen. Synthetic vaccines based on MUC1 tandem repeat motifs, comprising tumor‐associated 2,3‐sialyl‐T antigen, conjugated to the immunostimulating tetanus toxoid, are reported herein. Immunization with these vaccines in a simple water/oil emulsion produced a strong immune response in mice to which stimulation with complete Freund's adjuvant (CFA) was not superior. In both cases, high levels of IgG1 and IgG2a/b were induced in C57BL/6 mice. Additional glycosylation in the immunodominant PDTRP domain led to improved binding of the induced antisera to MCF‐7 breast tumor cells, compared with that of the monoglycosylated peptide vaccine.     

Serine Hydrolases in Lipid Homeostasis of the Placenta-Targets for Placental Function?

The metabolic state of pregnant women and their unborn children changes throughout pregnancy and adapts to the specific needs of each gestational week. These adaptions are accomplished by the actions of enzymes, which regulate the occurrence of their endogenous substrates and products in all three compartments: mother, placenta and the unborn. These enzymes determine bioactive lipid signaling, supply, and storage through the generation or degradation of lipids and fatty acids, respectively. This review focuses on the role of lipid-metabolizing serine hydrolases during normal pregnancy and in pregnancy-associated pathologies, such as preeclampsia, gestational diabetes mellitus, or preterm birth. The biochemical properties of each class of lipid hydrolases are presented, with special emphasis on their role in placental function or dysfunction. While, during a normal pregnancy, an appropriate tonus of bioactive lipids prevails, dysregulation and aberrant signaling occur in diseased states. A better understanding of the dynamics of serine hydrolases across gestation and their involvement in placental lipid homeostasis under physiological and pathophysiological conditions will help to identify new targets for placental function in the future.     

Resolvin E1 Improves Mitochondrial Function in Human Alveolar Epithelial Cells during Severe Inflammation

Severe inflammatory disorders such as sepsis are a major cause of morbidity and mortality worldwide. Mitochondrial dysfunction is regarded as a key feature involved in inflammation pathogenesis. In the present study, we investigated the impact of the omega-3 fatty acid-derived lipid mediator Resolvin E1 (RvE1) on mitochondrial function in experimental pulmonary inflammation. RvE1 was found to exert anti-inflammatory properties in human alveolar epithelial cells during severe inflammation. RvE1 is capable of restoring inflammation-induced mitochondrial dysfunction and the impaired imbalance of mitochondrial fission and fusion. Experimental inhibition of mitochondrial fission with Mdivi-1 in our model is associated with a significantly reduced inflammatory response and improved mitochondrial function. These findings suggest a novel functional mechanism for the beneficial effects of RvE1 in experimental pulmonary inflammatory reactions.     

Origin and Expansion of the Serine Protease Repertoire in the Myelomonocyte Lineage

The deepest evolutionary branches of the trypsin/chymotrypsin family of serine proteases are represented by the digestive enzymes of the gastrointestinal tract and the multi-domain proteases of the blood coagulation and complement system. Similar to the very old digestive system, highly diverse cleavage specificities emerged in various cell lineages of the immune defense system during vertebrate evolution. The four neutrophil serine proteases (NSPs) expressed in the myelomonocyte lineage, neutrophil elastase, proteinase 3, cathepsin G, and neutrophil serine protease 4, collectively display a broad repertoire of (S1) specificities. The origin of NSPs can be traced back to a circulating liver-derived trypsin-like protease, the complement factor D ancestor, whose activity is tightly controlled by substrate-induced activation and TNFα-induced locally upregulated protein secretion. However, the present-day descendants are produced and converted to mature enzymes in precursor cells of the bone marrow and are safely sequestered in granules of circulating neutrophils. The potential site and duration of action of these cell-associated serine proteases are tightly controlled by the recruitment and activation of neutrophils, by stimulus-dependent regulated secretion of the granules, and by various soluble inhibitors in plasma, interstitial fluids, and in the inflammatory exudate. An extraordinary dynamic range and acceleration of immediate defense responses have been achieved by exploiting the high structural plasticity of the trypsin fold.     

Socio-cognitive openness in online knowledge building discourse: does openness keep conversations going?

This study describes the socio-cognitive dynamics of collaborative online knowledge-building discourse among Dutch Master of Education students from the perspective of openness. A socio-cognitive openness framework consisting of four social and four cognitive components was used to analyze contributions to online collective knowledge building processes in two Knowledge Forum® databases. Analysis revealed that the contributions express a moderate level of openness, with higher social than cognitive openness. Three cognitive indicators of openness were positively associated with follow-up, while the social indicators of openness appeared to have no bearings on follow-up. Findings also suggested that teachers’ contributions were more social in nature and had less follow-up compared to students’ contributions. From the perspective of openness, the discourse acts of building knowledge and expressing uncertainty appear to be key in keeping knowledge building discourse going, in particular through linking new knowledge claims to previous claims and simultaneously inviting others to refine the contributed claim.

     

Discovery of Novel,Potent, and Specific Cell‐Death Inducers in the Jurkat Acute Lymphoblastic Leukemia Cell Line

The limited clinical efficacy of many cancer therapeutics has initiated intense research efforts toward the discovery of novel chemical entities in this field. In this study, 31 hit candidates were selected from nearly 800 000 database compounds in a ligand‐based virtual screening campaign. In turn, three of these hits were found to have (sub)micromolar potencies in proliferation assays with the Jurkat acute lymphatic leukemic cell line. In this assay, the three hits were found to exhibit higher potency than clinically tested cell‐death inducers (GDC‐0152, AT‐406, and birinapant). Importantly, antiproliferative activity toward non‐cancer peripheral blood mononuclear cells (PBMCs) was found to be marginal. Further biological characterization demonstrated the cell‐death‐inducing properties of these compounds. Biological testing of hit congeners excluded a nonspecific, toxic effect of the novel structures. Altogether, these findings may have profound relevance for the development of clinical candidates in tumor therapy.     

Influence of rotational speed on the microstructure and mechanical performance of friction-riveted thermosetting composite joints

Facing the actual demand for efficient joining technologies for multi-materials structures, friction riveting was shown to be an alternative joining technology for thermoset composite profiles in civil infrastructure. This process is based on plasticizing and deforming the tip of a rotating metallic rivet within a polymeric component through frictional heating. The feasibility of friction-riveted hybrid joints of Ti-6Al-4 V/glass-fibre reinforced thermoset polyester was already demonstrated in a separate work. This paper complements this study by analyzing the rivet rotational speed effect on the process temperature, joint microstructure and the local and global mechanical properties of the joint. Joints were produced using two different levels of rotational speed: 9000 and 10,000 rpm (the other parameters were kept constant). The results showed process temperatures (655–765 °C) up to 96% higher than the onset decomposition temperature of the polyester matrix (370 °C); this led to severe degradation of the composite in the joint area. The increase in rotational speed, and therefore in heat generation, led to a statistically insignificant increase of the rivet penetration depth and the rivet diameter widening. However, the extension of the degraded composite area increased 47% which was responsible to deteriorate in 50% the joint tensile strength (from 4.0 ± 1.2 kN to 2.0 ± 0.7 kN). Moreover, the microhardness map of the joined rivet evidenced possible phase transformations in the alloy, favouring the material hardening by increasing in rotational speed. However, no correlations could be established between the changes in hardness and the joint tensile strength since the joints majority failure by full rivet pull-out. Thereby, for the improvement of friction-riveted Ti-6Al-4 V/ glass-fibre reinforced thermoset polyester joints, the optimization of rotational speed is essential. This can guarantee the formation of efficient anchored joints and wider rivet tip deformation, concomitantly with the minimizing of the extension of the matrix degradation and finally leading to better tensile strength of the joints.