The Effect of GD1a Ganglioside-Expressing Bacterial Strains on Murine Norovirus Infectivity

In this study, we investigated the impact of GD1a-expressing bacterial strains on the infectivity of murine norovirus (MNV). Eligible bacterial strains were screened from a sewage sample using flow cytometry, and their genetic sequences of 16S rRNA were determined. The enzyme-linked immunosorbent assay (ELISA) was employed to analyze the binding between bacteria and MNV particles, and the plaque assay was used to assess the effects of GD1a-positive and negative strains on MNV infectivity. The result from ELISA shows that MNV particles are able to bind to both GD1a-positive and negative bacterial strains, but the binding to the GD1a-positive strain is more significant. The infectivity assay result further shows that the MNV infectious titer declined with an increasing concentration of GD1a-positive bacteria. The addition of anti-GD1a antibody in the infectivity assay led to the recovery of the MNV infectious titer, further confirming that the binding between MNV particles and bacterial GD1a ganglioside compromises MNV infectivity. Our findings highlight the role indigenous bacteria may play in the lifecycle of waterborne enteric viruses as well as the potential of exploiting them for virus transmission intervention and water safety improvement.

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Effect of Grape Seed Extract on Human Norovirus GII.4 and Murine Norovirus 1 in Viral Suspensions, on Stainless Steel Discs, and in Lettuce Wash Water

Applied and Environmental Microbiology ◽

10.1128/aem.01987-12 ◽

2012 ◽

Vol 78 (21) ◽

pp. 7572-7578 ◽

Cited By ~ 42

Author(s):

Dan Li ◽

Leen Baert ◽

Dongsheng Zhang ◽

Ming Xia ◽

Weiming Zhong ◽

...

Keyword(s):

Specific Binding ◽

Plaque Assay ◽

Oxygen Demand ◽

Grape Seed Extract ◽

Grape Seed ◽

Seed Extract ◽

Wash Water ◽

Enzyme Linked Immunosorbent Assay ◽

Murine Norovirus ◽

Reverse Transcription Pcr

ABSTRACTThe anti-norovirus (anti-NoV) effect of grape seed extract (GSE) was examined by plaque assay for murine norovirus 1 (MNV-1), cell-binding reverse transcription-PCR for human NoV GII.4, and saliva-binding enzyme-linked immunosorbent assay for human NoV GII.4 P particles, with or without the presence of interfering substances (dried milk and lettuce extract). GSE at 0.2 and 2 mg/ml was shown to reduce the infectivity of MNV-1 (>3-log PFU/ml) and the specific binding ability of NoV GII.4 to Caco-2 cells (>1-log genomic copies/ml), as well as of its P particles to salivary human histo-blood group antigen receptors (optical density at 450 nm of >0.8). These effects were decreased as increasing concentrations of dried milk (0.02 and 0.2%) or lettuce extract were added. Under an electron microscope, human NoV GII.4 virus-like particles showed inflation and deformation after treatment with GSE. Under conditions that simulated applications in the food industry, the anti-NoV effect of GSE using MNV-1 as a target organism was shown to be limited in surface disinfection (<1-log PFU/ml, analyzed in accordance with EN 13697:2001). However, a 1.5- to 2-log PFU/ml reduction in MNV-1 infectivity was noted when 2 mg of GSE/ml was used to sanitize water in the washing bath of fresh-cut lettuce, and this occurred regardless of the chemical oxygen demand (0 to 1,500 mg/ml) of the processing water.

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Modifying Plaque assay and Clearance test as tools in determination of phage typing for E. Coli bacterial interspecies

Baghdad Science Journal ◽

10.21123/bsj.10.1.161-167 ◽

2013 ◽

Vol 10 (1) ◽

pp. 161-167

Author(s):

Baghdad Science Journal

Keyword(s):

Plaque Assay ◽

High Specificity ◽

Inhibition Zone ◽

Phage Typing ◽

Sewage Sample ◽

Bacterial Strains ◽

E Coli ◽

Phage Strain ◽

Clearance Test

Bacteriophage of E. Coli interspecies from sewage samples were isolated , the phage particles were isolated from two different sewage samples . The first sample was collected from sewage sample of Baghdad university and the second sample was isolated from domestic sewage sample , first sample showed phages specialized for three E. Coli interspecies bacteria (first plate ) and two E. Coli interspecies bacteria (second plate ) , meanwhile second sample showed phage specialized for two E. Coli. interspeciesThe study of appearance of E coli phages from first sample showed three types of E. coli phages with different size of inhibition zone ( 1 , 0.7,0.5 )Cm respectively ( first plate ) , meanwhile E. Coli interspecies bacteria showed phages related with two interspecies with size of inhibition zone ( 0.5 ,0.4) Cm respectively ( second plate ), on other hand , the second sample showed also two interspecies E. coli with inhibition zone (1,0.8)Cm . experimental method has been designed which showed the modifying method of phage assay to determine phage typing assay . phage has been tested particles with different bacterial strains ( E. coli , shagilla and Serratia ) from different sources and the control was the host of each bacteriophages by taking the O.D for all the tests and controls , to setup new criteria for phage typing .:and this test is called ( Clearance Test ) The result showed that O.D for Test 1 , 2 , 3, was ( 1.6 , 1.2 . 1.7) for ( E. coli , shagilla and Serratia ) bacterial strains , meanwhile the control tests was ( 0.3 , 0.2, 0.4 ) for strains isolated from first sample (first and second plate ) and second samples with different interspecies respectively . This result can predict high specificity of phage strain and this method can be used to determine interspecies strains .So from this experiment we can identify only Clearance Test by measuring only O.D. of bacterial strain with different phages instead of going through plaque assay .

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THE EFFECT OF BACTERIAL STRAINS ON THE ENZYMATIC ACTIVITY OF SOILS IN IMPACT ZONE OF ATAMAN LAKE

STATE AND DEVELOPMENT PROSPECTS OF AGRIBUSINESS. In the frame of the XXIII Agribusiness Forum of the South of Russia and the Exhibition «Interagromash» Volume 1 ◽

10.23947/interagro.2020.1.119-120 ◽

2020 ◽

Author(s):

V.V. Zinchenko ◽

◽

E.S Fedorenko ◽

A.V Gorovtsov ◽

T.M Minkina ◽

...

Keyword(s):

Enzymatic Activity ◽

Dehydrogenase Activity ◽

Contaminated Soil ◽

Model Experiment ◽

Impact Zone ◽

Bacterial Strains ◽

The Impact

As a result of the model experiment, an increase in the enzymatic activity of meadow chernozem of the impact zone of Ataman Lake with the introduction of a strains mixture of metal-resistant microorganisms into the soil was established. The experiment has shown that the application of bacterial strains increases the dehydrogenase activity of contaminated soil by 51.8% compared to the variant without remediation

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The impact of FGF19/FGFR4 signaling inhibition in antitumor activity of multi-kinase inhibitors in hepatocellular carcinoma

Scientific Reports ◽

10.1038/s41598-021-84117-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hiroaki Kanzaki ◽

Tetsuhiro Chiba ◽

Junjie Ao ◽

Keisuke Koroki ◽

Kengo Kanayama ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Molecular Mechanisms ◽

Kinase Inhibitors ◽

Progression Free Survival ◽

Erk Signaling ◽

Enzyme Linked Immunosorbent Assay ◽

Antitumor Effects ◽

The Impact

AbstractFGF19/FGFR4 autocrine signaling is one of the main targets for multi-kinase inhibitors (MKIs). However, the molecular mechanisms underlying FGF19/FGFR4 signaling in the antitumor effects to MKIs in hepatocellular carcinoma (HCC) remain unclear. In this study, the impact of FGFR4/ERK signaling inhibition on HCC following MKI treatment was analyzed in vitro and in vivo assays. Serum FGF19 in HCC patients treated using MKIs, such as sorafenib (n = 173) and lenvatinib (n = 40), was measured by enzyme-linked immunosorbent assay. Lenvatinib strongly inhibited the phosphorylation of FRS2 and ERK, the downstream signaling molecules of FGFR4, compared with sorafenib and regorafenib. Additional use of a selective FGFR4 inhibitor with sorafenib further suppressed FGFR4/ERK signaling and synergistically inhibited HCC cell growth in culture and xenograft subcutaneous tumors. Although serum FGF19high (n = 68) patients treated using sorafenib exhibited a significantly shorter progression-free survival and overall survival than FGF19low (n = 105) patients, there were no significant differences between FGF19high (n = 21) and FGF19low (n = 19) patients treated using lenvatinib. In conclusion, robust inhibition of FGF19/FGFR4 is of importance for the exertion of antitumor effects of MKIs. Serum FGF19 levels may function as a predictive marker for drug response and survival in HCC patients treated using sorafenib.

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STING and cGAS gene expressions were downregulated among HIV-1-infected persons after antiretroviral therapy

Virology Journal ◽

10.1186/s12985-021-01548-6 ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Lorena Leticia Peixoto de Lima ◽

Allysson Quintino Tenório de Oliveira ◽

Tuane Carolina Ferreira Moura ◽

Ednelza da Silva Graça Amoras ◽

Sandra Souza Lima ◽

...

Keyword(s):

Gene Expression ◽

Viral Load ◽

T Cell ◽

Antiretroviral Therapy ◽

Cell Count ◽

Enzyme Linked Immunosorbent Assay ◽

Type I ◽

Α Level ◽

The Impact ◽

Hiv 1

Abstract Background The HIV-1 epidemic is still considered a global public health problem, but great advances have been made in fighting it by antiretroviral therapy (ART). ART has a considerable impact on viral replication and host immunity. The production of type I interferon (IFN) is key to the innate immune response to viral infections. The STING and cGAS proteins have proven roles in the antiviral cascade. The present study aimed to evaluate the impact of ART on innate immunity, which was represented by STING and cGAS gene expression and plasma IFN-α level. Methods This cohort study evaluated a group of 33 individuals who were initially naïve to therapy and who were treated at a reference center and reassessed 12 months after starting ART. Gene expression levels and viral load were evaluated by real-time PCR, CD4+ and CD8+ T lymphocyte counts by flow cytometry, and IFN-α level by enzyme-linked immunosorbent assay. Results From before to after ART, the CD4+ T cell count and the CD4+/CD8+ ratio significantly increased (p < 0.0001), the CD8+ T cell count slightly decreased, and viral load decreased to undetectable levels in most of the group (84.85%). The expression of STING and cGAS significantly decreased (p = 0.0034 and p = 0.0001, respectively) after the use of ART, but IFN-α did not (p = 0.1558). Among the markers evaluated, the only markers that showed a correlation with each other were STING and CD4+ T at the time of the first collection. Conclusions ART provided immune recovery and viral suppression to the studied group and indirectly downregulated the STING and cGAS genes. In contrast, ART did not influence IFN-α. The expression of STING and cGAS was not correlated with the plasma level of IFN-α, which suggests that there is another pathway regulating this cytokine in addition to the STING–cGAS pathway.

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Inhibition of p38 Mitogen-Activated Protein Kinase Impairs Mayaro Virus Replication in Human Dermal Fibroblasts and HeLa Cells

Viruses ◽

10.3390/v13061156 ◽

2021 ◽

Vol 13 (6) ◽

pp. 1156

Author(s):

Madelaine Sugasti-Salazar ◽

Yessica Y. Llamas-González ◽

Dalkiria Campos ◽

José González-Santamaría

Keyword(s):

Protein Expression ◽

Hela Cells ◽

Plaque Assay ◽

Dermal Fibroblasts ◽

Dependent Manner ◽

Human Dermal Fibroblasts ◽

Mitogen Activated Protein ◽

Mayaro Virus ◽

The Impact ◽

Dose Dependent

Mayaro virus (MAYV) hijacks the host’s cell machinery to effectively replicate. The mitogen-activated protein kinases (MAPKs) p38, JNK, and ERK1/2 have emerged as crucial cellular factors implicated in different stages of the viral cycle. However, whether MAYV uses these MAPKs to competently replicate has not yet been determined. The aim of this study was to evaluate the impact of MAPK inhibition on MAYV replication using primary human dermal fibroblasts (HDFs) and HeLa cells. Viral yields in supernatants from MAYV-infected cells treated or untreated with inhibitors SB203580, SP600125, U0126, or Losmapimod were quantified using plaque assay. Additionally, viral protein expression was analyzed using immunoblot and immunofluorescence. Knockdown of p38⍺/p38β isoforms was performed in HDFs using the PROTACs molecule NR-7h. Our data demonstrated that HDFs are highly susceptible to MAYV infection. SB203580, a p38 inhibitor, reduced MAYV replication in a dose-dependent manner in both HDFs and HeLa cells. Additionally, SB203580 significantly decreased viral E1 protein expression. Similarly, knockdown or inhibition of p38⍺/p38β isoforms with NR-7h or Losmapimod, respectively, affected MAYV replication in a dose-dependent manner. Collectively, these findings suggest that p38 could play an important role in MAYV replication and could serve as a therapeutic target to control MAYV infection.

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POS0460 ASSOCIATION OF ANTI-CITRULLINATED PROTEIN ANTIBODIES OF IgA SUBCLASSES WITH SUSTAINED REMISSION AND FLARE IN RHEUMATOID ARTHRITIS

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2021-eular.2004 ◽

2021 ◽

Vol 80 (Suppl 1) ◽

pp. 461-461

Author(s):

M. V. Sokolova ◽

J. Rech ◽

M. Hagen ◽

G. Schett ◽

U. Steffen (née Harre)

Keyword(s):

Rheumatoid Arthritis ◽

Enzyme Linked Immunosorbent Assay ◽

Sustained Remission ◽

Das28 Score ◽

Effector Functions ◽

Conventional Dmards ◽

The Impact ◽

Citrullinated Protein ◽

Iga Subclasses ◽

Over Time

Background:Understanding key mechanisms of flare development and sustained remission is one of the acute goals in modern rheumatology. Anti-citrullinated protein antibodies (ACPA) are the most abundant and specific autoantibodies in rheumatoid arthritis (RA) patients. However, the impact of ACPA of IgA isotype is poorly defined. IgA ACPA were previously shown to have a higher percentage of IgA2 in comparison to total IgA; and a correlation between IgA2% ACPA with the DAS28 score was observed in a previous study [1]. Of note, IgA1 and IgA2 were shown to exhibit different effector functions, with IgA2 being pro-inflammatory, which might be the background for its role in RA [1].Objectives:We aimed to investigate, whether IgA ACPA could be used as a predictive factor for flare development in RA; and to look further into the changes in IgA ACPA levels in patients remaining in stable remission versus patients developing flare.Methods:We analysed serum of 111 patients from a multicentre randomized controlled trial ‘RETRO’. The study observational period was 12 months. Patients in the trial had to be in stable remission (DAS28-ESR<2.6) for a minimum of 6 months and were randomized into 3 different treatment arms: continuation of treatment, tapering by 50% or a gradual tapering until discontinuation [2]. IgA ACPA concentrations were measured with an enzyme-linked immunosorbent assay on CCP2-pre-coated plates.Results:60% of patients had IgG-ACPA. IgA ACPA levels were higher among the IgG-ACPA-positive patients (median 4.7 versus 2.24 µg/ml, p<0.0001). Baseline IgA1 and 2 ACPA levels were not different between patients who had a flare later on in the study period and those remaining in remission, showing no predictive value for flare development. However, the percentage of IgA2 in ACPA was correlating with the first registered DAS28 after flare (r=0.36, p=0.046). After the 12 months study period, IgA2 ACPA as well as IgA2% ACPA decreased significantly in patients who remained in stable remission by 17.5% (median, p<0.0001) and 13.6% (p=0.0006), respectively. By contrast, there was no significant change in IgA2 ACPA levels over time in patients who developed a flare. IgA1 ACPA levels remained stable over time. Disease management strategies did not seem to influence IgA ACPA levels in a specific way, as baseline levels were similar between patients on biological and conventional DMARDs and changes in levels after 12 months did not depend on the assignment to either of the study arms.Conclusion:Neither IgA1 nor IgA2 ACPA levels were predictive of flare development or associated with treatment strategies (though rituximab, JAK-inhibitors and abatacept were not amongst treatment options). However, in patients remaining in sustained remission after 1 year a decrease in IgA2 and IgA2% ACPA was observed and IgA2% ACPA was associated with DAS28 score registered after flare. This could be an indication towards ACPA of IgA2 isotype contributing to the severity of flare, alongside other factors, and its reduction being associated with a prolonged state of remission.References:[1]Steffen U, Koeleman CA, Sokolova MV, et al. IgA subclasses have different effector functions associated with distinct glycosylation profiles. Nat Commun 11, 120 (2020).[2]Haschka J, Englbrecht M, Hueber AJ, et al. Relapse rates in patients with rheumatoid arthritis in stable remission tapering or stopping antirheumatic therapy: interim results from the prospective randomised controlled RETRO study. Ann Rheum Dis. 75:45-51 (2016).Disclosure of Interests:None declared

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Identification and Characterization of the First Virulent Phages, Including a Novel Jumbo Virus, Infecting Ochrobactrum spp.

International Journal of Molecular Sciences ◽

10.3390/ijms21062096 ◽

2020 ◽

Vol 21 (6) ◽

pp. 2096

Author(s):

Przemyslaw Decewicz ◽

Piotr Golec ◽

Mateusz Szymczak ◽

Monika Radlinska ◽

Lukasz Dziewit

Keyword(s):

Dna Methyltransferase ◽

Wastewater Treatment Plants ◽

Biogas Production ◽

Genome Mining ◽

Sewage Sample ◽

Bacterial Strains ◽

Regulatory Circuits ◽

A Genome ◽

Insightful Analysis

The Ochrobactrum genus consists of an extensive repertoire of biotechnologically valuable bacterial strains but also opportunistic pathogens. In our previous study, a novel strain, Ochrobactrum sp. POC9, which enhances biogas production in wastewater treatment plants (WWTPs) was identified and thoroughly characterized. Despite an insightful analysis of that bacterium, its susceptibility to bacteriophages present in WWTPs has not been evaluated. Using raw sewage sample from WWTP and applying the enrichment method, two virulent phages, vB_OspM_OC and vB_OspP_OH, which infect the POC9 strain, were isolated. These are the first virulent phages infecting Ochrobactrum spp. identified so far. Both phages were subjected to thorough functional and genomic analyses, which allowed classification of the vB_OspM_OC virus as a novel jumbo phage, with a genome size of over 227 kb. This phage encodes DNA methyltransferase, which mimics the specificity of cell cycle regulated CcrM methylase, a component of the epigenetic regulatory circuits in Alphaproteobacteria. In this study, an analysis of the overall diversity of Ochrobactrum-specific (pro)phages retrieved from databases and extracted in silico from bacterial genomes was also performed. Complex genome mining allowed us to build similarity networks to compare 281 Ochrobactrum-specific viruses. Analyses of the obtained networks revealed a high diversity of Ochrobactrum phages and their dissimilarity to the viruses infecting other bacteria.

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Impact of maternal supplementation with probiotics during pregnancy on atopic eczema in childhood – a meta-analysis

British Journal Of Nutrition ◽

10.1017/s0007114511003400 ◽

2011 ◽

Vol 107 (1) ◽

pp. 1-6 ◽

Cited By ~ 77

Author(s):

Katja Doege ◽

Donata Grajecki ◽

Birgit-Christiane Zyriax ◽

Elena Detinkina ◽

Christine zu Eulenburg ◽

...

Keyword(s):

Atopic Eczema ◽

Data Extraction ◽

Meta Analysis ◽

Significant Risk ◽

Controlled Trials ◽

Bacterial Strains ◽

Double Blind ◽

Double Blind Placebo ◽

Study Selection ◽

The Impact

In the present study, we sought to conduct a literature review of randomised, double-blind, placebo-controlled trials, which assessed the impact of probiotics intake during pregnancy on the development of eczema in children. A meta-analysis was conducted for comparison of the development of atopic eczema in children whose mothers took probiotics during pregnancyv.placebo. Study selection, quality appraisal and data extraction were performed independently and in duplicate. The studies were rated according to their size in order to calculate the influence of individual studies on the meta-analysis. A total of seven randomised, double-blind, placebo-controlled trials, published between 2001 and 2009, were selected from the PubMed and Ovid databases for the meta-analysis. The meta-analysis was performed with statistical software Stata/SE11.0. The completed meta-analysis of the seven studies shows a significant risk reduction for atopic eczema in children aged 2–7 years by the administration of probiotics during pregnancy (reduction 5·7 %;P = 0·022). However, this effect was only significant for lactobacilli (reduction 10·6 %;P = 0·045), but not for a mixture of various bacterial strains as probiotics (difference 3·06 %,P = 0·204). In conclusion, the meta-analysis shows that the administration of lactobacilli during pregnancy prevents atopic eczema in children aged from 2 to 7 years. However, a mixture of various bacterial strains does not affect the development of atopic eczema, independent of whether they contain lactobacilli or not.

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Systematic Literature Review on Burden of Clostridioides difficile Infection in India

Clinical Pathology ◽

10.1177/2632010x211013816 ◽

2021 ◽

Vol 14 ◽

pp. 2632010X2110138

Author(s):

Canna J Ghia ◽

Shaumil Waghela ◽

Gautam S Rambhad

Keyword(s):

Risk Factors ◽

Multiple Testing ◽

Final Analysis ◽

Antibiotic Usage ◽

Diagnostic Methods ◽

North India ◽

Enzyme Linked Immunosorbent Assay ◽

Chi Square ◽

Clostridioides Difficile ◽

The Impact

Background: Owing to limited diagnostic facilities and surveillance protocols, there is a paucity on the prevalence data of Clostridioides difficile infections (CDIs) in developing countries such as India. Objective: The aims of these studies are (1) to determine the prevalence of CDI in India, (2) to understand the risk factors of CDI, and (3) to determine the impact of different diagnostic methods on reported CDI rates. Method: A systematic literature search was conducted using PubMed and Google Scholar database to identify Indian studies reporting the prevalence of CDI. A total of 31 studies, published between 1990 and 2020 were included in the final analysis. A chi-square test was used to determine statistically significant association between prevalence rates, accuracy of different diagnosis methods, and antibiotic usage rates of CDI. Results: The prevalence of CDI was in the range of 3.4% to 18%, and the difference between regional prevalence of CDI was statistically significant ( P < .001). The use of antibiotics, hospital stay, comorbidities, recent surgery, and the use of proton-pump inhibitors was considered as risk factors for the development of CDI. Compared to other regions, the rate of antibiotic usage was significantly higher in North India ( P < .001). Among different diagnostic methods, C. difficile detection was significantly higher with enzyme-linked immunosorbent assay (18.02%) versus other multiple testing methods used ( P < .001). Conclusion: There is a significant burden of CDI across the country. Further surveillance studies are required to monitor changes in prevalence of CDI, risk factors, and accuracy of diagnosis methods for a better understanding of the disease burden in India.

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