Heterogenicity within the LPS Structure in Relation to the Chosen Genomic and Physiological Features of the Plant Pathogen Pectobacterium parmentieri

Pectobacterium parmentieri is a pectinolytic plant pathogenic bacterium causing high economic losses of cultivated plants. The highly devastating potential of this phytopathogen results from the efficient production of plant cell wall-degrading enzymes, i.e., pectinases, cellulases and proteases, in addition to the impact of accessory virulence factors such as motility, siderophores, biofilm and lipopolysaccharide (LPS). LPS belongs to pathogen-associated molecular patterns (PAMPs) and plays an important role in plant colonization and interaction with the defense systems of the host. Therefore, we decided to investigate the heterogeneity of O-polysaccharides (OPS) of LPS of different strains of P. parmentieri, in search of an association between the selected genomic and phenotypic features of the strains that share an identical structure of the OPS molecule. In the current study, OPS were isolated from the LPS of two P. parmentieri strains obtained either in Finland in the 1980s (SCC3193) or in Poland in 2013 (IFB5432). The purified polysaccharides were analyzed by utilizing 1D and 2D NMR spectroscopy (¹H, DQF-COSY, TOCSY, ROESY, HSQC, HSQC-TOCSY and HMBC) in addition to chemical methods. Sugar and methylation analyses of native polysaccharides, absolute configuration assignment of constituent monosaccharides and NMR spectroscopy data revealed that these two P. parmentieri strains isolated in different countries possess the same structure of OPS with a very rare residue of 5,7-diamino-3,5,7,9-tetradeoxy-l-glycero-l-manno-non-2-ulosonic acid (pseudaminic acid) substituted in the position C-8: →3)-β-d-Galf-(1→3)-α-d-Galp-(1→8)-β-Pse4Ac5Ac7Ac-(2→6)-α-d-Glcp-(1→6)-β-d-Glcp-(1→. The previous study indicated that three other P. parmentieri strains, namely IFB5427, IFB5408 and IFB5443, exhibit a different OPS molecule than SCC3193 and IFB5432. The conducted biodiversity-oriented assays revealed that the P. parmentieri IFB5427 and IFB5408 strains possessing the same OPS structure yielded the highest genome-wide similarity, according to average nucleotide identity analyses, in addition to the greatest ability to macerate chicory tissue among the studied P. parmentieri strains. The current research demonstrated a novel OPS structure, characteristic of at least two P. parmentieri strains (SCC3193 and IFB5432), and discussed the observed heterogenicity in the OPS of P. parmentieri in a broad genomic and phenotype-related context.     

Ficolin-2 Plasma Level Assesses Liver Fibrosis in Non-Alcoholic Fatty Liver Disease

Fibrosis is the strongest predictor for disease-specific mortality in non-alcoholic fatty liver diseases (NAFLD), but the need for liver biopsy limits its diagnosis. We assessed the performance of plasma ficolin-2 (FCN-2) as a biomarker of fibrosis identified by an in silico discovery strategy. Two hundred and thirty-five morbidly obese (MO) subjects with biopsy-proven NAFLD stratified by fibrosis stage (F0, n = 44; F1, n = 134; F2, n = 46; F3/F4, n = 11) and 40 cirrhotic patients were enrolled. The cohort was subdivided into discovery (n = 76) and validation groups (n = 159). The plasma level of FCN-2 and other candidate markers was determined. FCN-2 was inversely correlated with the stage of liver fibrosis (ρ = −0.49, p < 0.001) independently of steatosis (p = 0.90), inflammation (p = 0.57), and ballooning (p = 0.59). In the global cohort, FCN-2 level decreased significantly in a stepwise fashion from F0/F1 (median 4753 ng/mL) to F2–F3–F4 (2760 ng/mL) and in cirrhotic subjects (1418 ng/mL). The diagnostic performance of FCN-2 in detecting F ≥ 2 was higher than other indexes (APRI, FIB-4) (AUROC 0.82, 0.68, and 0.6, respectively). The accuracy improved when combined with APRI score and HDL values (FCNscore, AUROC 0.85). Overall, the FCN-2 plasma level can accurately discriminate liver fibrosis status (minimal vs. moderate/advanced) significantly improving the fibrosis diagnostic algorithms.     

Using ELP Repeats as a Scaffold for De Novo Construction of Gadolinium-Binding Domains within Multifunctional Recombinant Proteins for Targeted Delivery of Gadolinium to Tumour Cells

Three artificial proteins that bind the gadolinium ion (Gd³⁺) with tumour-specific ligands were de novo engineered and tested as candidate drugs for binary radiotherapy (BRT) and contrast agents for magnetic resonance imaging (MRI). Gd³⁺-binding modules were derived from calmodulin. They were joined with elastin-like polypeptide (ELP) repeats from human elastin to form the four-centre Gd³⁺-binding domain (4MBS-domain) that further was combined with F3 peptide (a ligand of nucleolin, a tumour marker) to form the F3-W4 block. The F3-W4 block was taken alone (E2-13W4 protein), as two repeats (E1-W8) and as three repeats (E1-W12). Each protein was supplemented with three copies of the RGD motif (a ligand of integrin αvβ3) and green fluorescent protein (GFP). In contrast to Magnevist (a Gd-containing contrast agent), the proteins exhibited three to four times higher accumulation in U87MG glioma and A375 melanoma cell lines than in normal fibroblasts. The proteins remained for >24 h in tumours induced by Ca755 adenocarcinoma in C57BL/6 mice. They exhibited stability towards blood proteases and only accumulated in the liver and kidney. The technological advantages of using the engineered proteins as a basis for developing efficient and non-toxic agents for early diagnosis of tumours by MRI as well as part of BRT were demonstrated.     

Effect of Bacterial Infection on Ghrelin Receptor Regulation in Periodontal Cells and Tissues

The effect of bacterial infection on the expression of growth hormone secretagogue receptor (GHS-R) was investigated in periodontal cells and tissues, and the actions of ghrelin were evaluated. GHS-R was assessed in periodontal tissues of rats with and without periodontitis. Human gingival fibroblasts (HGFs) were exposed to Fusobacterium nucleatum in the presence and absence of ghrelin. GHS-R expression was determined by real-time PCR and immunocytochemistry. Furthermore, wound healing, cell viability, proliferation, and migration were evaluated. GHS-R expression was significantly higher at periodontitis sites as compared to healthy sites in rat tissues. F. nucleatum significantly increased the GHS-R expression and protein level in HGFs. Moreover, ghrelin significantly abrogated the stimulatory effects of F. nucleatum on CCL2 and IL-6 expressions in HGFs and did not affect cell viability and proliferation significantly. Ghrelin stimulated while F. nucleatum decreased wound closure, probably due to reduced cell migration. Our results show original evidence that bacterial infection upregulates GHS-R in rat periodontal tissues and HGFs. Moreover, our study shows that ghrelin inhibited the proinflammatory actions of F. nucleatum on HGFs without interfering with cell viability and proliferation, suggesting that ghrelin and its receptor may act as a protective molecule during bacterial infection on periodontal cells.     

ICA1L Is Associated with Small Vessel Disease: A Proteome-Wide Association Study in Small Vessel Stroke and Intracerebral Haemorrhage

Small vessel strokes (SVS) and intracerebral haemorrhages (ICH) are acute outcomes of cerebral small vessel disease (SVD). Genetic studies combining both phenotypes have identified three loci associated with both traits. However, the genetic cis-regulation at the protein level associated with SVD has not been studied before. We performed a proteome-wide association study (PWAS) using FUSION to integrate a genome-wide association study (GWAS) and brain proteomic data to discover the common mechanisms regulating both SVS and ICH. Dorsolateral prefrontal cortex (dPFC) brain proteomes from the ROS/MAP study (N = 376 subjects and 1443 proteins) and the summary statistics for the SVS GWAS from the MEGASTROKE study (N = 237,511) and multi-trait analysis of GWAS (MTAG)-ICH–SVS from Chung et al. (N = 240,269) were selected. We performed PWAS and then a co-localization analysis with COLOC. The significant and nominal results were validated using a replication dPFC proteome (N = 152). The replicated results (q-value < 0.05) were further investigated for the causality relationship using summary data-based Mendelian randomization (SMR). One protein (ICA1L) was significantly associated with SVS (z-score = −4.42 and p-value = 9.6 × 10⁻⁶) and non-lobar ICH (z-score = −4.8 and p-value = 1.58 × 10⁻⁶) in the discovery PWAS, with a high co-localization posterior probability of 4. In the validation PWAS, ICA1L remained significantly associated with both traits. The SMR results for ICA1L indicated a causal association of protein expression levels in the brain with SVS (p-value = 3.66 × 10⁻⁵) and non-lobar ICH (p-value = 1.81 × 10⁻⁵). Our results show that the association of ICA1L with SVS and non-lobar ICH is conditioned by the cis-regulation of its protein levels in the brain.     

An Application of Computer‐Aided Molecular Design (CAMD) Using the Signature Molecular Descriptor–Part 2. Evaluating Newly Identified Surface Tension‐Reducing Substances for Potential Use as Shrinkage‐Reducing Admixtures

In this study, the use of computer‐aided molecular design (CAMD) is validated as a tool for enabling the discovery of new shrinkage‐reducing compounds for possible use in portland cement composites and is framed as one of many multiscale modeling tools in a broad hierarchy of possibilities. Twelve additives were tested for their ability to inhibit shrinkage in Type I ordinary portland cement under both autogenous and drying conditions. The 12 additives included two commercial shrinkage‐reducing admixtures (SRAs), two active ingredients of a commercial admixture [one of which was used to establish the quantitative structure–property relationships (QSPR)], two additional classified as potential SRA compounds based on the patent literature, four newly identified compounds predicted by using CAMD and an inverse quantitative structure–property relationship (I‐QSPR), and two other compounds use to establish the QSPR relationship. The newly identified I‐QSPR compounds were targeted for their ability to reduce the surface tension of water, a primary consideration for shrinkage‐reducing activity. Results for both drying shrinkage and autogenous shrinkage indicate that the designed compounds perform similar to commercial admixtures, yet have different chemical functionalities. Hydration data and set measurements were also considered since selection of new SRAs is a multiparameter problem with many constraints. Thus, these newly identified shrinkage‐reducing compounds can potentially provide additional options for use in portland cement concrete applications.     

Two-Step Processing Method for Blending High-Performance Polymers with Notable Thermal and Rheological Differences: PEI and PBT

Blends between high-performance polymers (HPP) are barely studied, especially those produced by melting processing. In this work, it is proposed a novel methodology to prepare blends between polymers with notable processing temperature differences: poly(ether imide) (PEI) and poly(butylene terephthalate) (PBT). Processing parameters are settled after thermal and rheological evaluation of pure materials, those results suggest these blends need to be produced by steps. It is found a synergistic effect such as lowering PEI processing temperature and reducing PBT hydrolysis at high temperatures. Propose methodology allows to produce blends between HPP in the whole composition range with the same processing conditions.     

Probiotics: An alternative strategy for combating salmonellosis: Immune mechanisms involved

Salmonella produces infections of different nature and severity depending of many factors including the Salmonella serovar involved, strain virulence, infective dose, host animal species, age and immune status of the host. The treatments against Salmonella infections rely on supportive and antibiotic therapy to eliminate the pathogen, but the development of resistance by Salmonella to the antimicrobials most commonly used limits its efficacy. Other disadvantages of antibiotic treatments are that they can lead to acute diarrhea (antimicrobials normally induce an imbalance of intestinal bacterial flora) and may produce chronic toxicity. Considering this undesired consequences of antibiotics and because at the present there are no effective oral vaccines which protect against salmonellosis, scientists have been searching for alternative methods to control enteric infections. In the present review, probiotics are proposed as an attractive possibility to attend this concern. Probiotic are live microorganisms, which when administered in adequate amounts confer a health benefit on the host. In vitro and in vivo studies showed the effectiveness of probiotic administration in the prevention or in the treatment against Salmonella infection. There are several mechanisms by which probiotic strains might exert their effects. They include non immune mechanisms (stabilization of the gut mucosal barrier, competition for adhesion, secretion of antimicrobial substances, etc.) and the modulation of the mucosal and systemic immune responses. These mechanisms are species and/or strain specific. There are also evidences that in some cases, a mix of probiotic strains can be more useful than each strain alone against this infection. In addition, the presence of one or more probiotic strains in a fermented product can improve the beneficial properties of the probiotic strains involved. It was also reviewed the security of probiotics administration after Salmonella infection in healthy host and in immunosuppressed or babies hosts. Although, the major part of the researches were performed in animal models through in vivo assays or by in vitro studies using human cell lines, some studies carried out in humans to verify the probiotic effects were also addressed in the present review. Nevertheless, is of critical importance to perform more clinical trials in humans to validate the results obtained with each specific probiotic strain or probiotic product.     

A Novel Insight into the Cardiotoxicity of Antineoplastic Drug Doxorubicin

Doxorubicin is a commonly used antineoplastic agent in the treatment of many types of cancer. Little is known about the interactions of doxorubicin with cardiac biomolecules. Serious cardiotoxicity including dilated cardiomyopathy often resulting in a fatal congestive heart failure may occur as a consequence of chemotherapy with doxorubicin. The purpose of this study was to determine the effect of exposure to doxorubicin on the changes in major amino acids in tissue of cardiac muscle (proline, taurine, glutamic acid, arginine, aspartic acid, leucine, glycine, valine, alanine, isoleucine, threonine, lysine and serine). An in vitro interaction study was performed as a comparison of amino acid profiles in heart tissue before and after application of doxorubicin. We found that doxorubicin directly influences myocardial amino acid representation even at low concentrations. In addition, we performed an interaction study that resulted in the determination of breaking points for each of analyzed amino acids. Lysine, arginine, β-alanine, valine and serine were determined as the most sensitive amino acids. Additionally we compared amino acid profiles of myocardium before and after exposure to doxorubicin. The amount of amino acids after interaction with doxorubicin was significantly reduced (p = 0.05). This fact points at an ability of doxorubicin to induce changes in quantitative composition of amino acids in myocardium. Moreover, this confirms that the interactions between doxorubicin and amino acids may act as another factor most likely responsible for adverse effects of doxorubicin on myocardium.