Full transcriptome analysis of early dorsoventral patterning in zebrafish

Understanding the molecular interactions that lead to the establishment of the major body axes during embryogenesis is one of the main goals of developmental biology. Although the past two decades have revolutionized our knowledge about the genetic basis of these patterning processes, the list of genes involved in axis formation is unlikely to be complete. In order to identify new genes involved in the establishment of the dorsoventral (DV) axis during early stages of zebrafish embryonic development, we employed next generation sequencing for full transcriptome analysis of normal embryos and embryos lacking overt DV pattern. A combination of different statistical approaches yielded 41 differentially expressed candidate genes and we confirmed by in situ hybridization the early dorsal expression of 32 genes that are transcribed shortly after the onset of zygotic transcription. Although promoter analysis of the validated genes suggests no general enrichment for the binding sites of early acting transcription factors, most of these genes carry "bivalent" epigenetic histone modifications at the time when zygotic transcription is initiated, suggesting a "poised" transcriptional status. Our results reveal some new candidates of the dorsal gene regulatory network and suggest that a plurality of the earliest upregulated genes on the dorsal side have a role in the modulation of the canonical Wnt pathway

A highly soluble, non-phototoxic, non-fluorescent blebbistatin derivative

Blebbistatin is a commonly used molecular tool for the specific inhibition of various myosin II isoforms both in vitro and in vivo. Despite its popularity, the use of blebbistatin is hindered by its poor water-solubility (below 10 micromolar in aqueous buffer) and blue-light sensitivity, resulting in the photoconversion of the molecule, causing severe cellular phototoxicity in addition to its cytotoxicity. Furthermore, blebbistatin forms insoluble aggregates in water-based media above 10 micromolar with extremely high fluorescence and also high adherence to different types of surfaces, which biases its experimental usage. Here, we report a highly soluble (440 micromolar in aqueous buffer), non-fluorescent and photostable C15 amino-substituted derivative of blebbistatin, called para-aminoblebbistatin. Importantly, it is neither photo- nor cytotoxic, as demonstrated on HeLa cells and zebrafish embryos. Additionally, para-aminoblebbistatin bears similar myosin II inhibitory properties to blebbistatin or para-nitroblebbistatin (not to be confused with the C7 substituted nitroblebbistatin), tested on rabbit skeletal muscle myosin S1 and on M2 and HeLa cells. Due to its drastically improved solubility and photochemical feature, as well as lack of photo- or cytotoxicity, para-aminoblebbistatin may become a feasible replacement for blebbistatin, especially at applications when high concentrations of the inhibitor or blue light irradiation is required

3D cell segregation geometry and dynamics are governed by tissue surface tension regulation

Tissue morphogenesis and patterning during development involve the segregation of cell types. Segregation is driven by differential tissue surface tensions generated by cell types through controlling cell-cell contact formation by regulating adhesion and actomyosin contractility-based cellular cortical tensions. We use vertebrate tissue cell types and zebrafish germ layer progenitors as in vitro models of 3-dimensional heterotypic segregation and developed a quantitative analysis of their dynamics based on 3D time-lapse microscopy. We show that general inhibition of actomyosin contractility by the Rho kinase inhibitor Y27632 delays segregation. Cell type-specific inhibition of non-muscle myosin2 activity by overexpression of myosin assembly inhibitor S100A4 reduces tissue surface tension, manifested in decreased compaction during aggregation and inverted geometry observed during segregation. The same is observed when we express a constitutively active Rho kinase isoform to ubiquitously keep actomyosin contractility high at cell-cell and cell-medium interfaces and thus overriding the interface-specific regulation of cortical tensions. Tissue surface tension regulation can become an effective tool in tissue engineering

A versatile modular vector set for optimizing protein expression among bacterial, yeast, insect and mammalian hosts

We have developed a unified, versatile vector set for expression of recombinant proteins, fit for use in any bacterial, yeast, insect or mammalian cell host. The advantage of this system is its versatility at the vector level, achieved by the introduction of a novel expression cassette. This cassette contains a unified multi-cloning site, affinity tags, protease cleavable linkers, an optional secretion signal, and common restriction endonuclease sites at key positions. This way, genes of interest and all elements of the cassette can be switched freely among the vectors, using restriction digestion and ligation without the need of polymerase chain reaction (PCR). This vector set allows rapid protein expression screening of various hosts and affinity tags. The reason behind this approach was that it is difficult to predict which expression host and which affinity tag will lead to functional expression. The new system is based on four optimized and frequently used expression systems (Escherichia coli pET, the yeast Pichia pastoris, pVL and pIEx for Spodoptera frugiperda insect cells and pLEXm based mammalian systems), which were modified as described above. The resulting vector set was named pONE series. We have successfully applied the pONE vector set for expression of the following human proteins: the tumour suppressor RASSF1A and the protein kinases Aurora A and LIMK1. Finally, we used it to express the large multidomain protein, Rho-associated protein kinase 2 (ROCK2, 164 kDa) and demonstrated that the yeast Pichia pastoris reproducibly expresses the large ROCK2 kinase with identical activity to the insect cell produced counterpart. To our knowledge this is among the largest proteins ever expressed in yeast. This demonstrates that the cost-effective yeast system can match and replace the industry-standard insect cell expression system even for large and complex mammalian proteins. These experiments demonstrate the applicability of our pONE vector set

Real-life efficacy of vedolizumab on endoscopic healing in inflammatory bowel disease: a nationwide Hungarian cohort study

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Az adalimumab hatékonysága és biztonságossága hagyományos kezelésre refrakter colitis ulcerosában

INTRODUCTION: Adalimumab was approved for the treatment of ulcerative colitis refractory to conventional therapy several years later than infliximab in Europe. Due to the relatively low remission rate observed in Ultra trials, data on the efficacy of adalimumab in ulcerative colitis are really helpful in the daily practice. AIM: The aim of this study was to prospectively collect data on induction and maintenance adalimumab therapy in patients with ulcerative colitis treated in Hungarian centres. METHOD: This prospective study collected data of all patients with ulcerative colitis treated with adalimumab in 10 Hungarian centres. The primary endpoints of the study were rates of remission, response and primary failure at week 12, and the rate of continuous clinical response, remission and loss of response at weeks 30, and 52. Secondary endpoints were endoscopic outcome at week 52 and comparison of the efficacy of adalimumab between treatment naive and infliximab-experienced patients. RESULTS: 73 patients with active ulcerative colitis were enrolled in the study. 75.3% of the patients exhibited clinical response after the induction at week 12. The probability of maintaining adalimumab treatment was 48.6% at week 52 with a continuous clinical response in 92% of these patients. Mucosal healing was achieved in 48.1% of the patients at week 52. Dose intensification was performed in 17.6% of the patients. Minor side effects developed in 4% of the patients and 5.4% of the patients underwent colectomy during the 1-year treatment period. CONCLUSIONS: These results coming from the real clinical setting demonstrate a favourable efficacy of adalimumab induction and maintenance therapy in patients with ulcerative colitis. Orv. Hetil., 2016, 157(18), 706-711

STRONG-malnutríció-rizikó és a percentilisek közötti összefüggések - STRONG 2.0

A malnutríció a gyermekgyógyászat egyik legjelentősebb klinikai eltérése. A STRONG a legújabb, malnutríció rizikóját szűrő pontrendszer. Jelen tanulmányunkban felmértük a testsúly, a testmagasság és a BMI percentilis értékeket, és a STRONG által mutatott rizikó közötti összefüggéseket elemeztük. A percentilis értékek és a STRONG rizikó között igazolt negatív korreláció azt mutatja, hogy a STRONG kérdőív hasznos lehet a betegek tápláltsági állapotának szűrésére. A STRONG előnye, hogy nem igényel mérést, követést, könnyen és azonnal elvégezhető, különösebb szakmai ismeret nélkül