Swine fecal samples collected from seven farms were screened for group C rotaviruses (RVCs) using a reverse transcription-polymerase chain reaction assay. A total of 380 samples were tested and 19.5% ...were positive. Of the 128 samples collected in 2012, 23.5% from nursing piglets and 8.5% from weaned piglets were RVC positive, with a higher RVC frequency in diarrheic (28.4%) than in non-diarrheic (6.6%) piglets. Two strains (RVC/Pig-wt/USA/RV0104/2011/G3PX and RVC/Pig-wt/USA/RV0143/2012/G6Px) from two different farms were characterized genetically to gain information on virus diversity based on full length sequences of the inner capsid VP6, enterotoxin NSP4 and the outer capsid VP7 and VP4 (partial for RV0104) genes. The VP6 gene of the two strains showed high (99%) nucleotide identity to one another, 84–91% identity to other porcine RVCstrains and 81–82% identity to human and bovine RVC strains. The NSP4 gene analysis revealed that RVC/Pig-wt/USA/RV0104/2011/G3PX and RVC/Pig-wt/USA/RV0143/2012/G6Px strains were not closely related to each other (87% identity), but shared higher identity with prototype RVC/Pig-wt/USA/Cowden/1980/G1Px strain (93% and 89%, respectively) and were more distantly related to human strains (72–76% identity). The VP7 gene analysis indicated that the two strains were distantly related to one another (72% identity). RVC/Pig-wt/USA/RV0143/2012/G6Px was most closely related to porcine RVC G6 strains (82–86% identity), whereas RVC/Pig-wt/USA/RV0104/2011/G3PX was most closely related to porcine HF (G3) strain (94% identity). Analysis of the full length nucleotide sequence of the VP4 gene revealed that RVC/Pig-wt/USA/RV0143/2012/G6Px was distantly related to porcine (75%), bovine (74%) and human (70%) strains. The deduced amino acid identities (69.5–75.6%) of VP4 between RVC/Pig-wt/USA/RV0143/2012/G6Px and other RVCs were low; hence, we propose that this strain comprises a new VP4 genotype. Our results indicate high genetic heterogeneity in RVCs genes and the concurrent co-circulation of different genotypes at the same time. Our findings are useful for the development of more accurate diagnostic tools, for basic research to understand gene function and to provide information for RVC diversity germane to vaccine development.
Rotavirus (RV) causes severe diarrhea in young children and animals worldwide. Several glycans terminating in sialic acids (SAs) and histo-blood group antigens (HBGAs) on intestinal epithelial cell ...(IEC) surface have been recognized to act as attachment sites for RV. IECs are protected by the double layer of mucus of which O-glycans (including HBGAs and SAs) are a major organic component. Luminal mucins, as well as bacterial glycans, can act as decoy molecules removing RV particles from the gut. The composition of the intestinal mucus is regulated by complex O-glycan-specific interactions among the gut microbiota, RV and the host. In this review, we highlight O-glycan-mediated interactions within the intestinal lumen prior to RV attachment to IECs. A better understanding of the role of mucus is essential for the development of alternative therapeutic tools including the use of pre- and probiotics to control RV infection.
Programmed death (apoptosis) is turned on in damaged or unwanted cells to secure their clean and safe self-elimination. The initial apoptotic events are coordinated in mitochondria, whereby several ...proapoptotic factors, including cytochrome c, are released into the cytosol to trigger caspase cascades. The release mechanisms include interactions of B-cell/lymphoma 2 family proteins with a mitochondria-specific phospholipid, cardiolipin, to cause permeabilization of the outer mitochondrial membrane. Using oxidative lipidomics, we showed that cardiolipin is the only phospholipid in mitochondria that undergoes early oxidation during apoptosis. The oxidation is catalyzed by a cardiolipin-specific peroxidase activity of cardiolipin-bound cytochrome c. In a previously undescribed step in apoptosis, we showed that oxidized cardiolipin is required for the release of proapoptotic factors. These results provide insight into the role of reactive oxygen species in triggering the cell-death pathway and describe an early role for cytochrome c before caspase activation.
Limited efficacy of rotavirus (RV) vaccines in children in developing countries and in animals remains a significant problem necessitating further search for additional approaches to control ...RV-associated gastroenteritis. During cell attachment and entry events, RV interacts with cell surface O-glycans including histo-blood group antigens (HBGAs). Besides modulation of the protective immunity against RV, several commensal and probiotic bacteria were shown to express HBGA-like substances suggesting that they may affect RV attachment and entry into the host cells. Moreover, some beneficial bacteria have been shown to possess the ability to bind host HBGAs via sugar specific proteins called lectins. However, limited research has been done to evaluate the effects of HBGA-expressing and/or HBGA-binding bacteria on RV infection. The aim of this study was to investigate the ability of selected commensal and probiotic bacteria to bind different RV strains via HBGAs and to block RV infection of IPEC-J2 cells. Our data indicated that Gram-negative probiotic Escherichia coli Nissle 1917 (E. coli Nissle 1917) and commensal Gram-positive (Streptococcus bovis and Bifidobacterium adolescentis) and Gram-negative (Bacteroides thetaiotaomicron, Clostridium clostridioforme and Escherichia coli G58 (E. coli G58) bacteria of swine origin expressed HBGAs which correlated with their ability to bind group A and C RVs. Additionally, Gram-positive E. coli 1917 and E. coli G58 demonstrated the ability to block RV attachment onto IPEC-J2 cells. Taken together, our results support the hypothesis that physical interactions between RVs and HBGA-expressing beneficial bacteria may limit RV replication.
The low efficacy of human rotavirus (HRV) vaccines in low- and middle-income countries (LMIC) remains a major challenge for global health. Protein-calorie malnutrition (kwashiorkor) affects the gut ...microbiota and compromises immune development, leading to environmental enteropathy, vaccine failures, and increased susceptibility to enteric diseases in young children. Relationship between diet and reduced vaccine efficacy in developing countries is not well established; therefore, we investigated the interconnections between the host-microbiota-nutrition-HRV vaccine using HRV-vaccinated, human infant faecal microbiota (HIFM)-transplanted neonatal gnotobiotic pigs fed with a protein deficient or sufficient diet. The microbiota from faecal, intestinal (duodenum, ileum, jejunum, and colon), and systemic tissue (liver, spleen, and mesenteric lymph node MLN) samples was analysed before and after HRV challenge using MiSeq 16S rRNA sequencing. Overall, microbiota from deficient fed HIFM pigs displayed, compared to the sufficient group, significantly higher Shannon index, especially in the faeces and lower intestines; higher level of Proteus and Enterococcus, and lower level of Bifidobacterium, Clostridium, and Streptococcus in the three types of samples collected (P<0.05); and higher unique operational taxonomic units (OTUs), especially in the systemic tissues. Further, the multivariate analysis between microbiota and immunologic data showed that 38 OTUs at the genus level correlated (r2≤0.5 or ≥-0.5; P<0.05) with at least one host immune response parameter (regulatory Tregs and transforming growth factor-β, effectors interferon (IFN)-γ+ CD4+ and CD8+ T cells, IFN-γ and interleukin (IL)-12, and inflammatory tumour necrosis factor-α, IL-17 and IL-22) and with opposite trends between diet groups. Differences described above were increased after HRV challenge. We demonstrated that a protein deficient diet affects the composition of the gut microbiota and those changes may further correlate with immune responses induced by HRV and perturbed by the deficient diet. Thus, our findings suggest that the reduced efficacy of HRV vaccine observed in Gn pig model is in part attributed to the altered microbiota composition.
•Evidence of RVA circulating in asymptomatic piglets at high rates.•Age, management and pig density influenced the incidence of RVA infections.•A striking genetic heterogeneity of the RVA circulating ...in East African pigs.•Genetic similarities between the pig P6 and P8 strains and corresponding human strains A possible reassortment event between swine and human RVA strains.•Asymptomatic animals could serve as natural reservoirs/sources of new emerging genotypes in both animals and humans, especially in view of the close proximity between them in some geographic regions.
Viral enteritis is a serious problem accounting for deaths in neonatal animals and humans worldwide. The absence of surveillance programs and diagnostic laboratory facilities have resulted in a lack of data on rotavirus associated diarrheas in pigs in East Africa. Here we describe the incidence of group A rotavirus (RVA) infections in asymptomatic young pigs in East Africa. Of the 446 samples examined, 26.2% (117/446) were positive for RVA. More nursing piglets (78.7%) shed RVA than weaned (32.9%) and grower (5.8%) pigs. RVA incidence was higher in pigs that were either housed_free-range (77.8%) or tethered_free-range (29.0%) than those that were free-range or housed or housed-tethered pigs. The farms with larger herd size (>10 pigs) had higher RVA prevalence (56.5%) than farms with smaller herd size (24.1–29.7%). This study revealed that age, management system and pig density significantly (p<0.01) influenced the incidence of RVA infections, with housed_free-range management system and larger herd size showing higher risks for RVA infection. Partial (811–1604nt region) sequence of the VP4 gene of selected positive samples revealed that different genotypes (P6, P8 and P13) are circulating in the study area with P8 being predominant. The P6 strain shared nucleotide (nt) and amino acid (aa) sequence identity of 84.4–91.3% and 95.1–96.9%, respectively, with known porcine and human P6 strains. The P8 strains shared high nt and aa sequence identity with known human P8 strains ranging from 95.6–100% to 92–100%, respectively. The P13 strains shared nt and aa sequence identity of 83.6–91.7% and 89.3–96.4%, respectively, only with known porcine P13 strains. No P8 strains yielded RNA of sufficient quality/quantity for full genome sequencing. However analysis of the full genome constellation of the P6, two P13 and one untypeable strains revealed that the P6 strain (Ke-003-5) genome constellation was G26-P6-I5-R1-C1-M1-A8-N1-T1-E1-H1, P13 strains (Ug-049 and Ug-453) had G5-P13-I5-R1-C1-M1-A8-N1-T7-E1-H1 while the untypeable strain (Ug-218) had G5-P?-I5-R1-C1-M1-A8-N1-T1-E1-H? In conclusion, P6 and P8 genotypes detected were genetically closely related to human strains suggesting the possibility of interspecies transmission. Further studies are required to determine the role of RVA in swine enteric disease burden and to determine the genetic/antigenic heterogeneity of the circulating strains for development of accurate diagnostic tools and to implement appropriate prophylaxis programs.
The paper presents the results of studying the dynamics of the magnetic field and electron fluxes of the Earth’s outer radiation belt with an energy of >2 MeV according to the
GOES-15
geostationary ...satellite during a fairly long period (October 16, 2016 to February 16, 2017) of moderate and weak magnetospheric activity caused by the arrival of a sequence of high-speed solar wind streams. The main variations in the electron flux in the geostationary orbit are caused by the movement, deceleration and acceleration of particles in the outer radiation belt of the Earth under the influence of geomagnetic activity. The results of a comparative analysis of variations in electron fluxes and components of the magnetospheric field testify to the predominant influence of the magnitude and structure of the magnetospheric field on the dynamics of relativistic electron fluxes in the outer radiation belt. Changes in the components of the magnetospheric magnetic field and in electron fluxes are results of a single process that occurs together with changes in the magnetosphere as a whole.
The structural and functional components of the microbial complex of chernozem, in particular, its prokaryotic component, were studied in order to assess the possible toxic effect of potassium ...chloride applied together with mineral nitrogen fertilizers. Soil samples of typical chernozem were taken from the experimental plots with application of nitrogen–phosphorus and nitrogen–phosphorus–potassium fertilizers. To obtain a stable effect of soluble salts on the microbial community of soil, long-term composting of the samples with alternating drying and moistening cycles was performed. During the first two years of composting, the r the suppression of carbon dioxide emission was detected. It was completely leveled out only five years later. The initial reduction in carbon dioxide emissions, as well as denitrification activity, reached twofold values. The negative effect was manifested when the content of chlorides and nitrates in the soil was significantly lower than the level established for slightly saline soils. Long-term composting of the samples treated with potassium chloride led to a decrease in the number and biomass of the metabolically active prokaryotic microorganisms, which confirmed its toxic effect on the microbial community of the soil. Representatives of the prokaryotic complex tolerant and sensitive towards the increased concentrations of chlorides and nitrates in the soil were identified. Almost all representatives of the Bacteria domain, except for Firmicutes and Verrucomicrobia phyla, were sensitive to these salts. Sensitivity to chlorine ions was confirmed at the generic level (
Streptomyces
and
Micromonospora
) for some representatives of the phylogenetic group of Actinobacteria. For the Archaea domain, representatives of the Euryarchaeota phylum were identified as the most tolerant towards the presence of chlorides. Thus, the suppression of the microbiological activity of chernozem under the impact of potassium chloride explains the earlier identified decrease in the availability of nutrients.
Changes in the dispersion state of heavy fuel oil with dissolved hydrogen sulfide, occurring under the action of low-energy wave treatment, were studied. Treatment with ultrasound and constant ...magnetic field ensures the reduction of the hydrogen sulfide content of the fuel oil to less than 10 ppm, and even to 1 ppm when the treatment is combined with using absorbents. The optimum parameters of the wave treatment were determined. The mean particle diameter of the dispersed fuel oil phase passes through a maximum in the course of wave treatment. The mechanism of processes occurring in the course of hydrogen sulfide removal from heavy fuel oil, based on concepts of petroleum disperse systems, was suggested.
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