scholarly journals Bacterial Species-Specific Modulatory Effects on Phenotype and Function of Camel Blood Leukocytes

2020 ◽  
Author(s):  
Jamal Hussen
Keyword(s):  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Monocyte Subset ◽  
Ros Production ◽  
Blood Leukocytes ◽  
E Coli ◽  
Mhc Ii ◽  
Bacterial Stimulation ◽  
Species Specific ◽  
And Function

Abstract Background: Recent studies have reported pathogen-species-specific modulating effects on the innate immune system. Escherichia coli, Staphylococcus aureus, and Streptococcus agalactiae are important pathogenic bacteria responsible for different infectious diseases in several animal species. In the present study, a whole blood culture and flow cytometry were used to investigate, whether stimulation with different bacterial species induces different immunomodulation patterns in camel leukocytes. Results: Stimulation with either of the bacterial species resulted in the expansion of the camel CD14highMHCIIhigh monocyte subset with a reduced fraction of CD14highMHCIIlow monocytes. For the CD14highMHCIIlow monocytes, however, only stimulation with S. aureus or S. agalactiae increased their fractions in blood. Although all bacterial species elicited the upregulation of cell surface MHC-II molecules on granulocytes, the increase was, however, highest on cells stimulated with S. aureus. The expression levels of the two adhesion molecules, CD11a and CD18, on neutrophils and monocytes were differently affected by bacterial stimulation. Functionally, E. coli failed to stimulate ROS production in monocytes, while induced a strong ROS production response in granulocytes. S. agalactiae elicited a week ROS production in granulocytes when compared to the other two pathogens. Conclusions: The different responsiveness of monocytes and granulocytes toward different bacterial species indicates different host-pathogen interaction mechanisms for the two cell populations. In addition, the phenotypic and functional differences between cells stimulated with E. coli, S. aureus, or S. agalactiae suggests pathogen-species-specific modulating effects of the bacterial pathogens on the camel innate myeloid cells.

scholarly journals Bacterial species-specific modulatory effects on phenotype and function of camel blood leukocytes

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Jamal Hussen
Keyword(s):  
Cell Surface ◽  
Adhesion Molecules ◽  
Mhc Class Ii ◽  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Monocyte Subset ◽  
Ros Production ◽  
Blood Leukocytes ◽  
Species Specific ◽  
And Function

Abstract Background Recent studies have reported pathogen-species-specific modulating effects on the innate immune system. Escherichia coli, Staphylococcus aureus, and Streptococcus agalactiae are important pathogenic bacteria responsible for different infectious diseases in several animal species. In the present study, a whole blood culture with S. aureus, E. coli, or S. agalactiae and flow cytometry were used to investigate, whether stimulation with different bacterial species induces different immunomodulation patterns in camel leukocytes. The expression of different cell surface myeloid markers and cell adhesion molecules on monocytes and neutrophils was investigated. In addition, the capacity of monocytes and neutrophils to produce reactive oxygen species (ROS) was analyzed. Results Stimulation with either of the bacterial species resulted in the expansion of the camel CD14highMHCIIhigh monocyte subset with a reduced fraction of CD14highMHCIIlow monocytes. For the CD14lowMHCIIhigh monocytes, however, only stimulation with S. aureus or S. agalactiae increased their fractions in blood. Although all bacterial species elicited the upregulation of cell surface MHC class II molecules on granulocytes, the increase was, however, highest on cells stimulated with S. aureus. The expression levels of the two adhesion molecules, CD11a and CD18, on neutrophils and monocytes were differently affected by bacterial stimulation. Functionally, E. coli failed to stimulate ROS production in monocytes, while induced a strong ROS production response in granulocytes. S. agalactiae elicited a week ROS production in granulocytes when compared to the other two pathogens. Conclusions The different responsiveness of monocytes and granulocytes toward different bacterial species indicates different host-pathogen interaction mechanisms for the two cell populations. In addition, the phenotypic and functional differences between cells stimulated with E. coli, S. aureus, or S. agalactiae suggests pathogen-species-specific modulating effects of the bacterial pathogens on the camel innate myeloid cells.

scholarly journals Combined Action of Human Commensal Bacteria and Amorphous Silica Nanoparticles on the Viability and Immune Responses of Dendritic Cells

2017 ◽  
Vol 24 (10) ◽  
Author(s):  
Giulia Malachin ◽  
Elisa Lubian ◽  
Fabrizio Mancin ◽  
Emanuele Papini ◽  
Regina Tavano
Keyword(s):  
Dendritic Cells ◽  
Silica Nanoparticles ◽  
Amorphous Silica ◽  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Commensal Bacteria ◽  
Content Type ◽  
E Coli ◽  
Synergistic Induction ◽  
Ifn Γ

ABSTRACT Dendritic cells (DCs) regulate the host-microbe balance in the gut and skin, tissues likely exposed to nanoparticles (NPs) present in drugs, food, and cosmetics. We analyzed the viability and the activation of DCs incubated with extracellular media (EMs) obtained from cultures of commensal bacteria (Escherichia coli, Staphylococcus epidermidis) or pathogenic bacteria (Pseudomonas aeruginosa, Staphylococcus aureus) in the presence of amorphous silica nanoparticles (SiO2 NPs). EMs and NPs synergistically increased the levels of cytotoxicity and cytokine production, with different nanoparticle dose-response characteristics being found, depending on the bacterial species. E. coli and S. epidermidis EMs plus NPs at nontoxic doses stimulated the secretion of interleukin-1β (IL-1β), IL-12, IL-10, and IL-6, while E. coli and S. epidermidis EMs plus NPs at toxic doses stimulated the secretion of gamma interferon (IFN-γ), tumor necrosis factor alpha (TNF-α), IL-4, and IL-5. On the contrary, S. aureus and P. aeruginosa EMs induced cytokines only when they were combined with NPs at toxic concentrations. The induction of maturation markers (CD86, CD80, CD83, intercellular adhesion molecule 1, and major histocompatibility complex class II) by commensal bacteria but not by pathogenic ones was improved in the presence of noncytotoxic SiO2 NP doses. DCs consistently supported the proliferation and differentiation of CD4+ and CD8+ T cells secreting IFN-γ and IL-17A. The synergistic induction of CD86 was due to nonprotein molecules present in the EMs from all bacteria tested. At variance with this finding, the synergistic induction of IL-1β was prevalently mediated by proteins in the case of E. coli EMs and by nonproteins in the case of S. epidermidis EMs. A bacterial costimulus did not act on DCs after adsorption on SiO2 NPs but rather acted as an independent agonist. The inflammatory and immune actions of DCs stimulated by commensal bacterial agonists might be altered by the simultaneous exposure to engineered or environmental NPs.

scholarly journals Antimicrobial Susceptibility Testing and Tentative Epidemiological Cutoff Values for FiveBacillusSpecies Relevant for Use as Animal Feed Additives or for Plant Protection

2018 ◽  
Vol 84 (19) ◽  
Author(s):  
Yvonne Agersø ◽  
Birgitte Stuer-Lauridsen ◽  
Karin Bjerre ◽  
Michelle Geervliet Jensen ◽  
Eric Johansen ◽  
...  
Keyword(s):  
Antimicrobial Resistance ◽  
Resistance Genes ◽  
Pathogenic Bacteria ◽  
Animal Feed ◽  
Bacterial Species ◽  
Feed Additives ◽  
Content Type ◽  
Cutoff Values ◽  
Antimicrobial Resistance Genes ◽  
Species Specific

ABSTRACTBacillus megaterium(n= 29),Bacillus velezensis(n= 26),Bacillus amyloliquefaciens(n= 6),Bacillus paralicheniformis(n= 28), andBacillus licheniformis(n= 35) strains from different sources, origins, and time periods were tested for the MICs for nine antimicrobial agents by the CLSI-recommended method (Mueller-Hinton broth, 35°C, for 18 to 20 h), as well as with a modified CLSI method (Iso-Sensitest [IST] broth, 37°C [35°C forB. megaterium], 24 h). This allows a proposal of species-specific epidemiological cutoff values (ECOFFs) for the interpretation of antimicrobial resistance in these species. MICs determined by the modified CLSI method were 2- to 16-fold higher than with the CLSI-recommended method for several antimicrobials. The MIC distributions differed between species for five of the nine antimicrobials. Consequently, use of the modified CLSI method and interpretation of resistance by use of species-specific ECOFFs is recommended. The genome sequences of all strains were determined and used for screening for resistance genes against the ResFinder database and for multilocus sequence typing. A putative chloramphenicol acetyltransferase (cat) gene was found in oneB. megateriumstrain with an elevated chloramphenicol MIC compared to the otherB. megateriumstrains. InB. velezensisandB. amyloliquefaciens, a putative tetracycline efflux gene,tet(L), was found in all strains (n= 27) with reduced tetracycline susceptibility but was absent in susceptible strains. AllB. paralicheniformisand 23% ofB. licheniformisstrains had elevated MICs for erythromycin and harboredermD. The presence of these resistance genes follows taxonomy suggesting they may be intrinsic rather than horizontally acquired. Reduced susceptibility to chloramphenicol, streptomycin, and clindamycin could not be explained in all species.IMPORTANCEWhen commercializing bacterial strains, likeBacillusspp., for feed applications or plant bioprotection, it is required that the strains are free of acquired antimicrobial resistance genes that could potentially spread to pathogenic bacteria, thereby adding to the pool of resistance genes that may cause treatment failures in humans or animals. Conversely, if antimicrobial resistance is intrinsic to a bacterial species, the risk of spreading horizontally to other bacteria is considered very low. Reliable susceptibility test methods and interpretation criteria at the species level are needed to accurately assess antimicrobial resistance levels. In the present study, tentative ECOFFs for fiveBacillusspecies were determined, and the results showed that the variation in MICs followed the respective species. Moreover, putative resistance genes, which were detected by whole-genome sequencing and suggested to be intrinsic rather that acquired, could explain the resistance phenotypes in most cases.

scholarly journals Structure and function of minor pilins of type IV pili

2019 ◽  
Vol 209 (3) ◽  
pp. 301-308 ◽  
Author(s):  
Theis Jacobsen ◽  
Benjamin Bardiaux ◽  
Olivera Francetic ◽  
Nadia Izadi-Pruneyre ◽  
Michael Nilges
Keyword(s):  
Pathogenic Bacteria ◽  
Type Iv Pili ◽  
Host Cells ◽  
Type Ii Secretion ◽  
Type Iv Pilus ◽  
Type Iv ◽  
Flexible Fibers ◽  
Multiple Copies ◽  
Species Specific ◽  
And Function

AbstractType IV pili are versatile and highly flexible fibers formed on the surface of many Gram-negative and Gram-positive bacteria. Virulence and infection rate of several pathogenic bacteria, such as Neisseria meningitidis and Pseudomonas aeruginosa, are strongly dependent on the presence of pili as they facilitate the adhesion of the bacteria to the host cell. Disruption of the interactions between the pili and the host cells by targeting proteins involved in this interaction could, therefore, be a treatment strategy. A type IV pilus is primarily composed of multiple copies of protein subunits called major pilins. Additional proteins, called minor pilins, are present in lower abundance, but are essential for the assembly of the pilus or for its specific functions. One class of minor pilins is required to initiate the formation of pili, and may form a complex similar to that identified in the related type II secretion system. Other, species-specific minor pilins in the type IV pilus system have been shown to promote additional functions such as DNA binding, aggregation and adherence. Here, we will review the structure and the function of the minor pilins from type IV pili.

scholarly journals Effect of Feed Supplemented With Vitamin C on Microbial Flora of Swine Faeces and Blood Morphology

2012 ◽  
Vol 56 (2) ◽  
pp. 171-175
Author(s):  
Beata Trawińska ◽  
Jerzy Lechowski ◽  
Antoni Polonis ◽  
Marta Kowaleczko
Keyword(s):  
Vitamin C ◽  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Intestinal Flora ◽  
Bacterial Count ◽  
Control Group ◽  
Total Bacterial Count ◽  
E Coli ◽  
Bacteriological Evaluation ◽  
Experimental Group

Abstract The studies involved gilts 6 weeks pre-partum allocated into the control and experimental groups. The experimental group received vitamin C at the dose of 2.5g/100 kg b.w./day. Faeces for analyses were collected for 3- and 6- week period of vitamin C dietary inclusion. The faecal material underwent quantitative and qualitative bacteriological evaluation. The count of Enterobacteriaceae was evaluated. The qualitative examination of these bacteria was made using the micro-plate method API 20E. Feed supplemented with vitamin C contributed to a statistically significant decline of the total bacterial count of Enterobacteriaceae in faeces. The qualitative bacterial analyses showed the presence of E. coli, Providecia sp., Proteus sp., and Salmonella sp. in the control and experimental groups. Enterobacter sp. was recovered only in the control group, while Lactobacillus sp. in the experimental group. The dietary administration of vitamin C significantly decreased the number of the studied bacterial species, except Salmonella rods. No statistically significant differences in the number of most blood morphotic elements following the 6- week supply of vitamin C were found; only the granulocyte count significantly increased, while lymphocyte numbers declined. Ascorbic acid inhibited the growth of pathogenic intestinal flora and reduced the pathogenic and relatively pathogenic bacteria count in the gastrointestinal tract and notably contributed to enhanced growth of beneficial bacteria.

scholarly journals Evaluating the risk of bacterial infections associated with the most handled Iraqi notes in Kalar

2019 ◽  
Vol 4 (1) ◽  
pp. 26-30 ◽  
Author(s):  
Hassan Mohammad Tawfeeq ◽  
Mohammed Hassan Fatah ◽  
Ahmed Mohammed Tofiq
Keyword(s):  
Bacterial Infections ◽  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Coagulase Negative Staphylococcus ◽  
Fresh Sample ◽  
Mannitol Salt Agar ◽  
E Coli ◽  
Paper Currency ◽  
Currency Note ◽  
And Staphylococcus Aureus

Every day new sources of microbial and especially bacterial infections are reported, which are not taken into account, the fact that these sources have been implicated in the outbreaks of these infections. The goals of the current research focused on the exploration of the scope of microbial pollution of the widely traded paper currency notes of the Iraqi currencies (250, 1000 and 5000 Iraqi Dinars) in Kalar city. 300 banknotes (100 samples for each of the denominations under investigation) in circulation were gathered from different categories of Kalar population and one fresh sample for each of the three currencies (control negative). Each bill was rinsed in 5 ml D.W then cultured on Nutrient agar, Mannitol Salt agar and MacConkey agar, respectively, then incubated at 37 ºC for up to 48 hours. Results revealed the rate of microbial contamination, specifically bacterial ones as 94%, 68%, and 60%, respectively on the denominations of 250, 1000, and 5000 of Iraqi Dinars. In a descending order, and with regard to the prevalence rate, bacterial species contaminated 250, 1000 and 5000 Iraqi denominations respectively were as follows: 55.31%, 32.35% and 36.66% for Bacillus sp.; 14.89%, 38.23% and 20% for coagulase-negative Staphylococcus; 8.51%, 8.82% and 20% for E. coli; 2.12%, 11.76 and 20% for Pseudomonas sp.; 2.12% for each of Klebsiella sp., and Salmonella sp.; 10.63% and 4.25% for Enterobacter sp. and Staphylococcus aureus, respectively, and only on 250 denomination;  2.94% and 5.88% for each of Corynebacterium sp. and Serratia sp. only on 1000 currency note; lastly, 3.33% for Proteus sp. on 5000 IQD only. These outcomes suggest that bacterial contamination of Iraqi Dinars, specifically the 250 denomination is risky and could be regarded as the real source of infectious diseases with the most dangerous pathogenic bacteria.  

scholarly journals STUDY THE INHIBITION ACTIVITY OF PURIFIED BACTERIOCIN FROM LOCAL ISOLATION Lactococcuslactis ssp. lactisagainst SOME PATHOGENIC BACTERIAL SPECIES ISOLATED FROM CLINICAL SAMPLES

2020 ◽  
Vol 12 (2) ◽  
pp. 34-49
Author(s):  
علاء حسين هامل1 ◽  
◽  
جيهان عبد الستار سلمان2 ◽  
رغد أكرم عزيز3 ◽  
◽  
...  
Keyword(s):  
Inhibitory Activity ◽  
Pathogenic Bacteria ◽  
Bacterial Species ◽  
Gel Filtration ◽  
Raw Milk ◽  
Diffusion Method ◽  
Clinical Samples ◽  
Inhibition Activity ◽  
E Coli ◽  
The One

This study aimed to study the inhibition activity of purified bacteriocin produced from the local isolation Lactococcuslactis ssp. lactis against pathogenic bacteria species isolated from clinical samples in some hospitals Baghdad city. Screening of L. lactis ssp. Lactis and isolated from the intestines fish and raw milk was performed in well diffusion method. The results showed that L. lactis ssp. lactis (Lc4) was the most efficient isolate in producing the bacteriocin as well observed inhibitory activity the increased that companied with the concentration, the concentration of the twice filtrate was better in obtaining higher inhibition diameters compared to the one-fold concentration. The concentrated bacteriocin was purified using the gel filtration column and Sephacryl S-200. The results showed the high inhibitory activity of the purified bacteriocin after the purification against the positive and negative bacteria of the Gram stain under study compared to the one-fold concentration and two-fold before purification , The diameters of the inhibition zones after gel-filtering of the purified bacteriocin reached S. aureus, S. epidermidis, P. aeruginosa, E. coli, E. clocae and S. marcescens (23, 25, 26, 20, 22 and 28) Mm respectively. The carbohydrate content of purified bacteriocin from L. lactis ssp. lactis (Lc4) isolate was 6.02% with a molecular weight of 6310 Dalton. The results showed that purified bacteriocin retained its inhibitory activity at pH 2-10 and showed the highest inhibition at pH 4-6 and lost at pH 12. The purified bacteriocin was characterized by thermal stability. It retained its effectiveness when exposed to 40, 60, 80, 100°C for 30, 15, 5 minutes and 120°C for 15.5 minutes and lost 50% of its effectiveness when exposed to 120°C for 30 minutes. Results The purified bacteriocin was effectively retained when treated with enzyme pepsin and trypsin of 37°C for one hour and at pH 7.

scholarly journals Microbiota–host interactions shape ageing dynamics

2020 ◽  
Vol 375 (1808) ◽  
pp. 20190596 ◽  
Author(s):  
Miriam Popkes ◽  
Dario Riccardo Valenzano
Keyword(s):  
Microbial Diversity ◽  
Microbial Communities ◽  
Pathogenic Bacteria ◽  
Immune Surveillance ◽  
Host Interactions ◽  
Disease States ◽  
Individual Fitness ◽  
Metabolite Synthesis ◽  
Species Specific ◽  
And Function

Occupying the interface between host and environment, host-associated microbes play fundamental roles in nutrient absorption, essential metabolite synthesis, development of the immune system, defence against pathogens and pathogenesis. Microbiota composition and function is rather stable during adulthood, while it dramatically changes during early development, frailty and disease. Ageing is associated with progressive decrease of homeostasis, often resulting in disruption of the physiological balance between host and commensal microbes, ultimately leading to dysbiosis and host demise. Generally, high microbial diversity is associated with health and a youthful state, while low individual microbial diversity and larger inter-individual microbial diversity is associated with ageing and disease states. Different species are equipped with species-specific commensal, symbiotic and pathogenic microbial communities. How and whether the specific host–microbiota consortia co-evolved with host physiology to ensure homeostasis and promote individual fitness remains an open question. In this essay, we propose that the evolution of vertebrate-specific immune adaptations may have enabled the establishment of highly diverse, species-specific commensal microbial communities. We discuss how the maintenance of intact immune surveillance mechanisms, which allow discrimination between commensal and pathogenic bacteria, fail during ageing and lead to the onset of known ageing-related diseases. We discuss how host–microbiota interactions are key to maintaining homeostasis despite external perturbations, but also how they affect a range of host-specific ageing-related phenotypes. This article is part of the theme issue ‘The role of the microbiome in host evolution’.

scholarly journals Cross-kingdom recognition of bacterial small RNAs induces transgenerational pathogenic avoidance

2019 ◽  
Author(s):  
Rachel Kaletsky ◽  
Rebecca S. Moore ◽  
Lance L. Parsons ◽  
Coleen T. Murphy
Keyword(s):  
Small Rnas ◽  
Pathogenic Bacteria ◽  
Escape Behavior ◽  
Bacterial Species ◽  
Future Generations ◽  
Transgenerational Inheritance ◽  
Signaling System ◽  
Specific Behavior ◽  
C Elegans ◽  
Species Specific

AbstractWe recently discovered that C. elegans can pass on a learned avoidance of pathogenic Pseudomonas aeruginosa (PA14) to four generations of its progeny. This transgenerational inheritance is bacterial species-specific, but how C. elegans recognizes and distinguishes different bacteria and transmits this information to future generations is not apparent. Here we show that small RNAs purified from pathogenic PA14 are sufficient not only to induce avoidance of pathogens in mothers, but also to confer transgenerational inheritance of this species-specific behavior for four generations, all without direct contact with pathogenic bacteria. This behavior requires the small RNA transporters SID-1 and SID-2, RNA interference pathway components, the piRNA Piwi/Argonaute pathway, a functioning germline, and TGF-β ligand daf-7 expression in the ASI sensory neuron. Our results suggest that C. elegans “reads” small RNAs expressed by pathogenic bacteria, and uses this information to induce an escape behavior that lasts for four additional generations. C. elegans may have evolved this trans-kingdom signaling system to avoid pathogens in abundant classes of bacteria in its environment and its microbiome.

scholarly journals Heterologous Expression of Der Homologs in an Escherichia coli der Mutant and Their Functional Complementation

2016 ◽  
Vol 198 (17) ◽  
pp. 2284-2296 ◽  
Author(s):  
Eunsil Choi ◽  
Nalae Kang ◽  
Young Jeon ◽  
Hyun-Sook Pai ◽  
Sung-Gun Kim ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pathogenic Bacteria ◽  
Ribosomal Subunit ◽  
Functional Complementation ◽  
Ribosomal Subunits ◽  
Content Type ◽  
E Coli ◽  
Serovar Typhimurium ◽  
Species Specific ◽  
Null Strain

ABSTRACTThe uniqueEscherichia coliGTPase Der (double Era-like GTPase), which contains tandemly repeated GTP-binding domains, has been shown to play an essential role in 50S ribosomal subunit biogenesis. The depletion of Der results in the accumulation of precursors of 50S ribosomal subunits that are structurally unstable at low Mg2+concentrations. Der homologs are ubiquitously found in eubacteria. Conversely, very few are conserved in eukaryotes, and none is conserved in archaea. In the present study, to verify their conserved role in bacterial 50S ribosomal subunit biogenesis, we cloned Der homologs from two gammaproteobacteria,Klebsiella pneumoniaeandSalmonella entericaserovar Typhimurium; two pathogenic bacteria,Staphylococcus aureusandNeisseria gonorrhoeae; and the extremophileDeinococcus radioduransand then evaluated whether they could functionally complement theE. colider-null phenotype. OnlyK. pneumoniaeandS. Typhimurium Der proteins enabled theE. coli der-null strain to grow under nonpermissive conditions. Sucrose density gradient experiments revealed that the expression ofK. pneumoniaeandS. Typhimurium Der proteins rescued the structural instability of 50S ribosomal subunits, which was caused byE. coliDer depletion. To determine what allows their complementation, we constructed Der chimeras. We found that only Der chimeras harboring both the linker and long C-terminal regions could reverse the growth defects of theder-null strain. Our findings suggest that ubiquitously conserved essential GTPase Der is involved in 50S ribosomal subunit biosynthesis in various bacteria and that the linker and C-terminal regions may participate in species-specific recognition or interaction with the 50S ribosomal subunit.IMPORTANCEInEscherichia coli, Der (double Era-like GTPase) is an essential GTPase that is important for the production of mature 50S ribosomal subunits. However, to date, its precise role in ribosome biogenesis has not been clarified. In this study, we used five Der homologs from gammaproteobacteria, pathogenic bacteria, and an extremophile to elucidate their conserved function in 50S ribosomal subunit biogenesis. Among them,Klebsiella pneumoniaeandSalmonella entericaserovar Typhimurium Der homologs implicated the participation of Der in ribosome assembly inE. coli. Our results show that the linker and C-terminal regions of Der homologs are correlated with its functional complementation inE. coli dermutants, suggesting that they are involved in species-specific recognition or interaction with 50S ribosomal subunits.

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