The protective role of Coenzyme Q10 in metallothionein-3 expression in liver and kidney upon rats’ exposure to lead acetate

Molecular Biology Reports - Metallothionein-3 (MT3) is an antioxidant protein that alters after exposure to heavy metals. In this study, we investigated the hepatic and renal expression of MT3 gene...     

An in silico analysis on the photoproteins Mnemiopsin 1 and Mnemiopsin 2 to explain the experimental results

Mnemiopsin 1 (Mn1) and Mnemiopsin 2 (Mn2) are photoproteins found in Mnemiopsis leidyi. We have tried to answer the question of whether the structural features of photoproteins can explain the observed activity data. According to the activity measurements data, they have the same characteristic wavelength. However, the initial intensity of Mn2 is significantly higher than that of Mn1, and decay time of Mn1 (0.92 s⁻¹) is lower than that of Mn2 (1.46 s⁻¹). The phylogenetic analysis demonstrates that, compared with Obelin and Aequorin from Obelia longissima and Aequorea victoria, respectively, a gene modification event may have caused the expansion of the N-terminal side of all photoproteins from M. leidyi. An in silico study has shown that the stability of the photoprotein–substrate complex of Mn2 is higher than that of Mn1, indicating a higher affinity of the substrate for Mn2 compared with Mn1. It was revealed that the active EF-hand loops 1 and III in Mn2 is locally more rigid compared with those in Mn1. We concluded that different stability of the photoprotein complexes leads to different initial intensity. While different patterns of the local dynamics of loops I and III may influence the decay rate.     

CD44 standard and variant isoform expression in normal human skin appendages and epidermis

 CD44 isoforms have been implicated in tumor progression and metastasis formation. This study presents a thorough immunohistochemical analysis of CD44 standard and isoform expression in normal human skin appendages and epidermis applying monoclonal antibodies against CD44s, CD44v3, -v4, -v5, -v6, and -v9. An improved immunohistochemical protocol with microwave-based antigen retrieval in paraffin sections and heavy metal amplification of the diaminobenzidine reaction product provided enhanced resolution and sensitivity as compared to studies on frozen sections. The hair follicle, the seborrheic and eccrine sweat glands were strongly positive for all CD44 isoforms studied. In the latter, the clear cells but not the dark (intercalated) cells were positive. The sudoriferous ducts adjacent to the glands were weakly positive for all CD44 isoforms and strongly positive near the skin surface. In the apocrine glands, the basal cells showed only a moderate positivity. The myoepithelial cells expressed only CD44s. In the epidermis, all CD44 isoforms were detectable, with strongest CD44 immunostaining in the lower third of the stratum spinosum and weaker staining in the stratum basale and the upper two-thirds of the stratum granulosum. The stratum granulosum and corneum were unreactive. Thus, a regional and cell type-specific CD44 expression was revealed. Accepted: 10 May 1996     

A framework for modelling soil structure dynamics induced by biological activity

Soil degradation is a worsening global phenomenon driven by socio‐economic pressures, poor land management practices and climate change. A deterioration of soil structure at timescales ranging from seconds to centuries is implicated in most forms of soil degradation including the depletion of nutrients and organic matter, erosion and compaction. New soil–crop models that could account for soil structure dynamics at decadal to centennial timescales would provide insights into the relative importance of the various underlying physical (e.g. tillage, traffic compaction, swell/shrink and freeze/thaw) and biological (e.g. plant root growth, soil microbial and faunal activity) mechanisms, their impacts on soil hydrological processes and plant growth, as well as the relevant timescales of soil degradation and recovery. However, the development of such a model remains a challenge due to the enormous complexity of the interactions in the soil–plant system. In this paper, we focus on the impacts of biological processes on soil structure dynamics, especially the growth of plant roots and the activity of soil fauna and microorganisms. We first define what we mean by soil structure and then review current understanding of how these biological agents impact soil structure. We then develop a new framework for modelling soil structure dynamics, which is designed to be compatible with soil–crop models that operate at the soil profile scale and for long temporal scales (i.e. decades, centuries). We illustrate the modelling concept with a case study on the role of root growth and earthworm bioturbation in restoring the structure of a severely compacted soil.     

Neuraminidase-associated plasminogen recruitment enables systemic spread of natural avian Influenza viruses H3N1

Repeated outbreaks due to H3N1 low pathogenicity avian influenza viruses (LPAIV) in Belgium were associated with unusually high mortality in chicken in 2019. Those events caused considerable economic losses and prompted restriction measures normally implemented for eradicating high pathogenicity avian influenza viruses (HPAIV). Initial pathology investigations and infection studies suggested this virus to be able to replicate systemically, being very atypical for H3 LPAIV. Here, we investigate the pathogenesis of this H3N1 virus and propose a mechanism explaining its unusual systemic replication capability. By intravenous and intracerebral inoculation in chicken, we demonstrate systemic spread of this virus, extending to the central nervous system. Endoproteolytic viral hemagglutinin (HA) protein activation by either tissue-restricted serine peptidases or ubiquitous subtilisin-like proteases is the functional hallmark distinguishing (H5 or H7) LPAIV from HPAIV. However, luciferase reporter assays show that HA cleavage in case of the H3N1 strain in contrast to the HPAIV is not processed by intracellular proteases. Yet the H3N1 virus replicates efficiently in cell culture without trypsin, unlike LPAIVs. Moreover, this trypsin-independent virus replication is inhibited by 6-aminohexanoic acid, a plasmin inhibitor. Correspondingly, in silico analysis indicates that plasminogen is recruitable by the viral neuraminidase for proteolytic activation due to the loss of a strongly conserved N-glycosylation site at position 130. This mutation was shown responsible for plasminogen recruitment and neurovirulence of the mouse brain-passaged laboratory strain A/WSN/33 (H1N1). In conclusion, our findings provide good evidence in natural chicken strains for N1 neuraminidase-operated recruitment of plasminogen, enabling systemic replication leading to an unusual high pathogenicity phenotype. Such a gain of function in naturally occurring AIVs representing an established human influenza HA-subtype raises concerns over potential zoonotic threats.     

Aberrant expression of lncRNAs SNHG6, TRPM2-AS1, MIR4435-2HG,and hypomethylation of TRPM2-AS1 promoter in colorectal cancer

Accumulating evidence has indicated that deregulation of lncRNAs plays essential roles in colorectal cancer (CRC) carcinogenesis. The goal of this study was to analyze the expression of lncRNAs in colorectal cancer and their association with clinicopathological variables. Bioinformatics analysis of published CRC microarray data was performed to identify the important lncRNAs. The expression levels of candidate genes were assessed in the human colon cancer/normal cell lines, CRC, adenomatous colorectal polyps, and their marginal tissues by qRT-PCR. Moreover, the methylation status of the TRPM2-AS1 promoter was studied using qMSP assay. Furthermore, we investigated the molecular mechanisms of these lncRNAs in CRC progression using in silico analysis. Microarray analysis revealed that lncRNAs SNHG6, MIR4435-2HG, and TRPM2-AS1 were upregulated in CRC. These results were validated in colon cell lines. Moreover, qRT-PCR showed that the expression levels of SNHG6 and TRPM2-AS1 were upregulated in the colorectal tumor tissues compared with their paired tissues. Nonetheless, there was no significant increase in MIR4435-2HG expression in CRC samples. Furthermore, we observed a significant hypomethylation of TRPM2-AS1 promoter and its activation in CRC tissues. By in silico analysis, we found that the lncRNAs upregulation could promote proliferation and drug resistance of colorectal cancer cells via miRNAs sponging and modulation of their targets expression. In conclusion, based on our results upregulation of SNHG6 and TRPM2-AS1, and hypomethylation of TRPM2-AS1 promoter might be considered as potential diagnostic biomarkers for CRC initiation and development.     

Optimization of the Emerson–Trinder enzymatic reaction by response surface methodology

The Emerson–Trinder reaction has been optimized in this work using an initial rate spectrophotometric method and response surface methodology (RSM). In this investigation, the variation range of critical variables along with the fixed parameters were selected based on a preliminary ‘one at a time’ (OVAT) procedure for the subsequent RSM chemometric analysis as follows: pH (6–10), buffer concentration (50–250?mM), 4-aminoantipyrine (4-AAP) concentration (1–5?mM), temperature (25–45°C). The optimum values of fixed parameters were: 4-fluorophenol (4-FP, 30?mM), horseradish peroxidase (HRP) enzyme activity (0.12?U?mL^?1), and the fixed concentration of the H₂O₂ in the chemometric experiments was 11.4 µM. The non-linear nature of the experimental response of the reaction system was explained by a second-order polynomial equation, which revealed the impact of the experimental factors, their interactions and also their optimum values. The results of the reported RSM analysis proved to be quite appropriate for the design and optimization of this reaction, as illustrated by the relatively high value of the determination coefficient (R²=96.7%) for the fitting of quadratic model, along with the satisfactory results generated by the analysis of variance (ANOVA). All the evaluated analytical characteristics of this method: typical reaction progress curves, resulting linear calibration curve, within-day precisions at low and at high levels, and the upper and lower detection limits were, also, reported. In addition, to check the quality of the optimization and validity of the model, the assay of H₂O₂, in pooled serum matrix and in cosmetic samples, was performed.