Urinary thrombomodulin is down regulated in schistosomiasis associated bladder cancer

BackgroundThrombomodulin (TM) is a surface glycoprotein and expressed in many cancers. The aim of the present study was to detect the expression levels of TM in plasma and urine of bladder cancer patients and to compare these levels to the clinicopathological data of the patients as well as the ploidy status of their exfoliated urinary cells. We studied the levels of TM in plasma and urine samples of 57 bladder cancer patients and 10 controls using the (ELISA) assay and compared the results to the ploidy status of the cells taken from the patents urine samples as well as their clinicopathological profile.ResultsUrinary TM was significantly down regulated while plasma TM was significantly up regulated in bladder cancer patients. Plasma TM was significantly higher in SCC than TCC patients. The sensitivity and specificity of urinary TM were 90% and 86%, respectively. While the sensitivity and specificity of plasma TM were 76% and 80%, respectively.ConclusionUrinary TM is significantly down regulated, while plasma TM is significantly up regulated in bladder cancer as compared to the control group. Urinary TM has superior sensitivity and specificity over plasma TM. Urinary TM could be used as a predictive marker in bladder cancer. Further studies are needed to detect the prognosis significance of thrombomodulin in schistosomiasis associated bladder cancer.     

Trichinella spiralis: infection changes serum paraoxonase-1 levels, lipid profile, and oxidative status in rats

Paraoxonase-1 (PON1) is an HDL-associated enzyme with anti-atherogenic properties. Reduced PON1 activity has previously been observed in Nippostrongylus brasiliensis-infected rats. However, the effect of chronic zoonotic nematode infections on serum PON1 activity has not yet been studied. Therefore, we evaluated the effect of Trichinella spiralis infection on serum PON1 activity, the lipid profile, and oxidative stress in rats. There were significant reductions in serum PON1 activities (Day 2-Week 7 post-infection) in rats infected with T. spiralis, and these reductions were associated with significant increases in the serum levels of triglyceride and LDL/VLDL, as well as a significant reduction in the level of HDL. Moreover, T. spiralis infection was associated with a status of oxidative stress indicated by increased concentrations of superoxide dismutase and malondialdehyde. Given the zoonotic prevalence of T. spiralis and the cardioprotective role of PON1, further mechanistic research in this area is warranted.     

High efficiency of targeted mutagenesis in arabidopsis via meiotic promoter-driven expression of Cas9 endonuclease

Key message

The use of a meiosis I-specific promoter increased the efficiency of targeted mutagenesis and will facilitate the manipulation of homologous recombination.

Abstract

The CRISPR/Cas9 system has been harnessed for targeted engineering of eukaryotic genomes, including plants; however, CRISPR/Cas9 efficiency varies considerably in different plant tissues and species. In Arabidopsis, the generation of homozygous or bi-allelic mutants in the first (T1) generation is inefficient. Here, we used specific promoters to drive the expression of Cas9 during meiosis to maximize the efficiency of recovering heritable mutants in T1 plants. Our data reveal that the use of a promoter active in meiosis I resulted in high-efficiency (28 %) recovery of targeted mutants in the T1 generation. Moreover, this method enabled efficient simultaneous targeting of three genes for mutagenesis. Taken together, our results show that the use of meiosis-specific promoters will improve methods for functional genomic analysis and studying the molecular underpinnings of homologous recombination.

     

Large and giant vesicles "decorated" with chitosan: effects of pH, salt or glucose stress, and surface adhesion

This paper describes the behavior of large and giant unilamellar vesicles (LUVs and GUVs, respectively) in the presence of chitosan, a positively charged polyelectrolyte. Variation of the zeta-potential of LUVs as a function of chitosan concentration is studied for two different molecular weights (MW) after a preliminary study devoted to pH and salt effects on zeta-potential in order to discriminate among the effects of protons, salt, and chitosan concentrations. The difference observed between pH and salt effects on the one hand and chitosan on the other allows us to conclude there is a strong LUV-chitosan interaction. In presence of chitosan, the zeta-potential of LUVs becomes positive and two distinct regimes of variation are suggested and interpreted as follows: a first step consists of chitosan adsorption flat on the membrane (independent of MW) followed by a possible reorganization of the polymer of higher molecular weight on the surface, giving rise to loops. Then a comparative observation of the effect of pH and salt by optical microscopy is made on naked and chitosan-decorated GUVs. Results further confirm a membrane-chitosan interaction and are interpreted in the light of the results obtained for LUVs in terms of both electrostatic and hydrophobic interaction. A large majority of decorated vesicles remain stable down to pH = 1 while in the absence of chitosan they burst quickly at pH between 2 and 3. Osmotic pressure and net charge change due to addition of HCl results in a decrease in the diameter of the decorated vesicles, which remain spherical while forming tubes of lipids. In presence of NaCl, a higher resistance of decorated vesicles is also evidenced (they are stable for NaCl concentrations up to 10-1 M while naked vesicles burst when [NaCl] is between 10-2 and 10-3 M). At higher salt concentration, aggregation of decorated vesicles occurs, which is attributed to the screening of electrostatic repulsions between vesicles covered by the positively charged chitosan. Finally, adhesion of vesicles on a positively charged surface is investigated. In absence of chitosan, the vesicles immediately burst when they come in contact with the surface. On the contrary, suspension of chitosan-vesicles remain stable down to pH = 1.5. Under gentle flow vesicles move: they do not adhere on the substrate, probably due to the repulsion between positively adsorbed charged chitosan and substrate; spherical deflation occurs, but in this case daughter vesicles are formed instead of lipid tubes.     

Photoaffinity labeling the agonist binding domain of α4β4 and α4β2 neuronal nicotinic acetylcholine receptors with [I]epibatidine and 5[I]A-85380

The development of nicotinic acetylcholine receptor (nAChR) agonists, particularly those that discriminate between neuronal nAChR subtypes, holds promise as potential therapeutic agents for many neurological diseases and disorders. To this end, we photoaffinity labeled human α4β2 and rat α4β4 nAChRs affinity-purified from stably transfected HEK-293 cells, with the agonists [¹²⁵I]epibatidine and 5[¹²⁵I]A-85380. Our results show that both agonists photoincorporated into the β4 subunit with little or no labeling of the β2 and α4 subunits respectively. [¹²⁵I]epibatidine labeling in the β4 subunit was mapped to two overlapping proteolytic fragments that begin at β4V102 and contain Loop E (β4I109-P120) of the agonist binding site. We were unable to identify labeled amino acid(s) in Loop E by protein sequencing, but we were able to demonstrate that β4Q117 in Loop E is the principal site of [¹²⁵I]epibatidine labeling. This was accomplished by substituting residues in the β2 subunit with the β4 homologs and finding [¹²⁵I]epibatidine labeling in β4 and β2F119Q subunits with little, if any, labeling in α4, β2, or β2S113R subunits. Finally, functional studies established that the β2F119/β4Q117 position is an important determinant of the receptor subtype-selectivity of the agonist 5I-A-85380, affecting both binding affinity and channel activation.     

Oxadiazolone bioisosteres of pregabalin and gabapentin

A series of oxadiazolone bioisosteres of pregabalin 1 and gabapentin 2 were prepared, and several were found to exhibit similar potency for the α₂-δ subunit of voltage-gated calcium channels. Oxadiazolone 9 derived from 2 achieved low brain uptake but was nevertheless active in models of osteoarthritis. The high clearance associated with compound 9 was postulated to be a consequence of efflux by OAT and/or OCT, and was attenuated on co-administration with cimetidine or probenecid.     

Biocatalytic properties of a peroxidase-active cell-free extract from onion solid wastes: caffeic acid oxidation

The exploitation of food residual sources consists of a major factor in reducing the polluting load of food industry wastes and developing novel added-value products. Plant food residues including trimmings and peels might contain a range of enzymes capable of transforming bio-organic molecules with potential phytotoxicity, including hydrolases, peroxidases and polyphenoloxidases. Although the use of bacterial and fungal enzymes has gained interest in studies pertaining to bioremediation applications, plant enzymes have been given less attention or even disregarded. In this view, this study aimed at the investigating the use of a crude peroxidase preparation from onion solid by-products for oxidising caffeic acid, a widespread o-diphenol, whose various derivatives may occur in food industry wastes, such as olive mill waste waters. Increased enzyme activity was observed at a pH value of 5, but considerable activity was also retained for pH up to 7. Favourable temperatures for increased activity varied between 20°C and 40°C, 30°C being the optimal. Liquid chromatography-mass spectrometry analysis of a homogenate/H₂O₂-treated caffeic acid solution revealed the existence of a tetramer as major oxidation product. Based on the data generated, a putative pathway for the formation of the peroxidase-mediated caffeic acid tetramer was proposed.