Minimal Antigenic Evolution after a Decade of Norovirus GII.4 Sydney_2012 Circulation in Humans.

Norovirus is a major human pathogen that can cause severe gastroenteritis in vulnerable populations. The extensive viral diversity presented by human noroviruses constitutes a major roadblock for the development of effective vaccines. In addition to the large number of genotypes, antigenically distinct variants of GII.4 noroviruses have chronologically emerged over the last 3 decades. The last variant to emerge, Sydney_2012, has been circulating at high incidence worldwide for over a decade. We analyzed 1449 capsid sequences from GII.4 Sydney_2012 viruses to determine genetic changes indicative of antigenic diversification. Phylogenetic analyses show that Sydney_2012 viruses scattered within the tree topology with no single cluster dominating during a given year or geographical location. Fourteen residues presented high variability, 7 of which mapped to 4 antigenic sites. Notably, ~52% of viruses presented mutations at 2 or more antigenic sites. Mutational patterns showed that residues 297 and 372, which map to antigenic site A, changed over time. Virus-like particles (VLPs) developed from wild-type Sydney_2012 viruses and engineered to display all mutations detected at antigenic sites were tested against polyclonal sera and monoclonal antibodies raised against Sydney_2012 and Farmington_Hills_2002 VLPs. Minimal changes in reactivity were detected with polyclonal sera and only 4 MAbs lost binding, with all mapping to antigenic site A. Notably, reversion of residues from Sydney_2012 reconstituted epitopes from ancestral GII.4 variants. Overall, this study demonstrates that, despite circulating for over a decade, Sydney_2012 viruses present minimal antigenic diversification and provides novel insights on the diversification of GII.4 noroviruses that could inform vaccine design. IMPORTANCE GII.4 noroviruses are the major cause of acute gastroenteritis in all age groups. This predominance has been attributed to the continued emergence of phylogenetically discrete variants that escape immune responses to previous infections. The last GII.4 variant to emerge, Sydney_2012, has been circulating at high incidence for over a decade, raising the question of whether this variant is undergoing antigenic diversification without presenting a major distinction at the phylogenetic level. Sequence analyses that include >1400 capsid sequences from GII.4 Sydney_2012 showed changes in 4 out of the 6 major antigenic sites. Notably, while changes were detected in one of the most immunodominant sites over time, these resulted in minimal changes in the antigenic profile of these viruses. This study provides new insights on the mechanism governing the antigenic diversification of GII.4 norovirus that could help in the development of cross-protective vaccines to human noroviruses.

Progress and perspectives of metabolic biomarkers in human aortic dissection.

BACKGROUND: Aortic dissection (AD) significantly threated human cardiovascular health, extensive clinical-scientific research programs have been executed to uncover the pathogenesis and prevention. Unfortunately, no specific biomarker was identified for the causality or development of human AD. AIM OF REVIEW: Metabolomics, a high-throughput technique capable of quantitatively detecting metabolites, holds considerable promise in discovering specific biomarkers and unraveling the underlying pathways involved. Aiming to provide a metabolite prediction in human AD, we collected the metabolomics data from 2003 to 2023, and diligently scrutinized with the online system MetaboAnalyst 6.0. KEY SCIENTIFIC CONCEPTS OF REVIEW: Based on the data obtained, we have concluded the metabolic dynamics were highly correlated with human AD. Such metabolites (choline, serine and uridine) were frequently involved in the AD. Besides, the pathways, including amino acids metabolism and lipids metabolism, were also dysregulated in the disease. Due to the current limitation of metabolism analysis, the integrative omics data including genomics, transcriptomics, and proteomics were required for developing the specific biomarker for AD.

Local injection of micro-dose anti-interleukin-17A antibody for palmoplantar pustulosis: A real-world study.

Palmoplantar pustulosis (PPP), a chronic and stubborn skin disease, is mainly confined to the palms or/and soles, making it possible for localized use of therapeutic antibodies. In this real-world prospective cohort study, 8 patients with PPP received palms/soles injections of ixekizumab (0.8 mg in 0.1 ml) every 2 to 8 weeks due to the COVID-19 pandemic. The treatment endpoint was a 75% improvement from baseline in Palmoplantar Pustulosis/Psoriasis Area and Severity Index (PPPASI 75). At week 8, 75%, 50% and 12.5% of 8 patients reached PPPASI 50, PPPASI 75 and PPPASI 90. At week 12, 100%, 75% and 25% of 8 patients reached PPPASI 50, PPPASI 75 and PPPASI 90. This is the first study to evaluate the efficacy and safety of local injection of micro-dose ixekizumab for PPP in real clinical practice. A high proportion of patients rapidly achieved PPPASI 75, and maintained long-term efficacy with satisfactory safety.

Balancing the influenza neuraminidase and hemagglutinin responses by exchanging the vaccine virus backbone.

Virions are a common antigen source for many viral vaccines. One limitation to using virions is that the antigen abundance is determined by the content of each protein in the virus. This caveat especially applies to viral-based influenza vaccines where the low abundance of the neuraminidase (NA) surface antigen remains a bottleneck for improving the NA antibody response. Our systematic analysis using recent H1N1 vaccine antigens demonstrates that the NA to hemagglutinin (HA) ratio in virions can be improved by exchanging the viral backbone internal genes, especially the segment encoding the polymerase PB1 subunit. The purified inactivated virions with higher NA content show a more spherical morphology, a shift in the balance between the HA receptor binding and NA receptor release functions, and induce a better NA inhibitory antibody response in mice. These results indicate that influenza viruses support a range of ratios for a given NA and HA pair which can be used to produce viral-based influenza vaccines with higher NA content that can elicit more balanced neutralizing antibody responses to NA and HA.

Paracholeplasma manati sp. nov. isolated from Florida manatees (Trichechus manatus latirostris).

Four novel strains of a member of the genus Paracholeplasma (OakleyT, Holly, Lorelei and Ariel) were isolated from skin of Florida manatees (Trichechus manatus latirostris). These strains were phenotypically and genetically characterized and compared with the known species of the genera Acholeplasma (A.), Alteracholeplasma (Al.), Haploplasma (H.), Paracholeplasma (P.) and Mariniplasma (M.). All the strains produced acid from glucose but did not hydrolyze arginine or urea. All were propagated in ambient air supplemented with 5±1 % CO2 at 35-37 °C using SP4-Z, Columbia and brain-heart infusion medium. Colonies on solid medium showed a typical fried-egg appearance and transmission electron microscopy revealed a typical mycoplasma-like cellular morphology. The results of phylogenetic analyses based on partial 16S rRNA, rpoB, gyrB and parE gene sequences and the whole proteome data indicated that the novel species is a unique species but phylogenetically closely related to Paracholeplasma vituli, Paracholeplasma morum and 'Paracholeplasma brassicae'. The average nucleotide identity and digital DNA-DNA hybridization values between strain OakleyT and the closely related species were significantly lower than the accepted thresholds for describing novel prokaryotic species at the genomic level. On the basis of the genomic, phenotypic and phylogenetic properties, the novel strains represent a novel species of the genus Paracholeplasma, for which the name Paracholeplasma manati sp. nov. with the type strain OakleyT (=NCTC 14352T =DSM 110686T) is proposed. The genomic DNA G+C content and complete draft genome size for the type strain are 38.35 % and 1 873 856 bp, respectively.

Streptococcus sciuri sp. nov., Staphylococcus marylandisciuri sp. nov. and Staphylococcus americanisciuri sp. nov., isolated from faeces of eastern grey squirrel (Sciurus carolinensis).

One novel Streptococcus strain (SQ9-PEAT) and two novel Staphylococcus strains (SQ8-PEAT and GRT3T) were isolated from faeces of a wild eastern grey squirrel. The strains were non-spore-forming, non-motile Gram-positive cocci, facultative anaerobes. The genomes for these strains were sequenced. The 16S rRNA gene and core-genome-based phylogenetic analyses showed that strain SQ9-PEAT was closely related to Streptococcus hyointestinalis, strain SQ8-PEAT to Staphylococcus pettenkoferi and Staphylococcus argensis, and strain GRT3T to Staphylococcus rostri, Staphylococcus muscae and Staphylococcus microti. Average nucleotide identity and pairwise digital DNA-DNA hybridization values calculated for these novel strains compared to type strain genomes of phylogenetically related species within the genera Streptococcus and Staphylococcus clearly revealed that strain SQ9-PEAT represents a novel species of the genus Streptococcus and strains SQ8-PEAT and GRT3T represent two novel species of the genus Staphylococcus. Phenotypical features of these novel type strains differed from the features of the type strains of other phylogenetically related species. MALDI-TOF mass spectrometry supported identification of these novel species. Based on these data, we propose one novel species of the genus Streptococcus, for which the name Streptococcus sciuri sp. nov. with the type strain SQ9-PEAT (=DSM 114656T=CCUG 76426T=NCTC 14727T) is proposed, and two novel species of the genus Staphylococcus, for which the names Staphylococcus marylandisciuri sp. nov. with the type strain SQ8-PEAT (=DSM 114685T=CCUG 76423T=NCTC 14723T) and Staphylococcus americanisciuri sp. nov. with the type strain GRT3T (=DSM 114696T=CCUG 76427T=NCTC 14722T) are proposed. The genome G+C contents are 38.29, 36.49 and 37.26 mol% and complete draft genome sizes are 1 692 266, 2 371 088 and 2 237 001 bp for strains SQ9-PEAT, SQ8-PEAT and GRT3T, respectively.

Neisseria montereyensis sp. nov., Isolated from Oropharynx of California Sea Lion (Zalophus californianus): Genomic, Phylogenetic, and Phenotypic Study.

A novel Neisseria strain, designated CSL10203-ORH2T, was isolated from the oropharynx of a wild California sea lion (Zalophus californianus) that was admitted to The Marine Mammal Center in California, USA. The strain was originally cultured from an oropharyngeal swab on BD Phenylethyl Alcohol (PEA) agar with 5% sheep blood under aerobic conditions. Phylogenetic analyses based on 16S rRNA, rplF, and rpoB gene sequences and the core genome sequences indicated that the strain was most closely related to only N. zalophi CSL 7565T. The average nucleotide identity and digital DNA-DNA hybridization values between strain CSL10203-ORH2T and the closely related species N. zalophi CSL 7565T were 89.84 and 39.70%, respectively, which were significantly lower than the accepted species-defined thresholds for describing novel prokaryotic species at the genomic level. Both type strains were phenotypically similar but can be easily and unambiguously distinguished between each other by the analysis of their housekeeping genes, e.g., rpoB, gyrB, or argF. The major fatty acids in both type strains were C12:0, C16:0, C16:1-c9, and C18:1-c11. Based on the genomic, phenotypic, and phylogenetic properties, the novel strain represents a novel species of the genus Neisseria, for which the name Neisseria montereyensis sp. nov. with the type strain CSL10203-ORH2T (= DSM 114706T = CCUG 76428T = NCTC 14721T) is proposed. The genome G + C content is 45.84% and the complete draft genome size is 2,310,535 bp.

Genotype-Specific Neutralization of Norovirus Is Mediated by Antibodies Against the Protruding Domain of the Major Capsid Protein.

Human noroviruses are the most common viral agents of acute gastroenteritis. Recently, human intestinal enteroids were shown to be permissive for norovirus infection. We tested their suitability as a system to study norovirus neutralization. Hyperimmune sera raised against virus-like particles (VLPs) representing different genotypes showed highly specific neutralization activity against GII.4 and GII.6 noroviruses. Carbohydrate blocking assays and neutralization exhibited similar patterns in antibody responses. Notably, sera produced against chimeric VLPs that presented swapped structural shell and protruding (P) domains, from different genotypes showed that neutralization is primarily mediated by antibodies mapping to the P domain of the norovirus capsid protein. This study provides empirical information on the antigenic differences among genotypes as measured by neutralization, which could guide vaccine design.

Mycoplasma miroungirhinis sp. nov. and Mycoplasma miroungigenitalium sp. nov., isolated from northern elephant seals (Mirounga angustirostris), Mycoplasma phocoenae sp. nov., isolated from harbour porpoise (Phocoena phocoena), and Mycoplasma phocoeninasale sp. nov., isolated from harbour porpoise and California sea lions (Zalophus californianus).

Seven novel independent strains of Mycoplasma species were isolated from northern elephant seals (ES2806-NAST, ES2806-GENT, ES3157-GEN-MYC and ES3225-GEN-MYC), a harbour porpoise (C264-GENT and C264-NAST), and a California sea lion (CSL7498). These strains were phenotypically and genetically characterized and compared to the known Mycoplasma species. Four strains (C264-GENT, C264-NAST, CSL7498 and ES2806-NAST) hydrolysed arginine but not urea and did not produce acid from carbohydrates. Strains ES2806-GENT, ES3157-GEN-MYC and ES3225-GEN-MYC did not produced acid from carbohydrates and did not hydrolyse arginine or urea; hence, it is assumed that organic acids are used as the energy source for them. All were isolated and propagated in ambient air supplemented with 5±1 % CO2 at +35-37 °C using either SP4 or PPLO medium. Colonies on solid medium showed a typical fried-egg appearance and transmission electron microscopy revealed a typical mycoplasma cellular morphology. The complete genomes were sequenced for all type strains. Average nucleotide and amino acid identity analyses showed that these novel strains were distant from the phylogenetically closely related Mycoplasma species. Based on these data, we propose four novel species of the genus Mycoplasma, for which the name Mycoplasma miroungirhinis sp. nov. is proposed with the type strain ES2806-NAST (=NCTC 14430T=DSM 110945T), Mycoplasma miroungigenitalium sp. nov. is proposed with the type strain ES2806-GENT (=NCTC 14429T=DSM 110944T) and representative strains ES3157-GEN-MYC and ES3225-GEN-MYC, Mycoplasma phocoenae sp. nov. is proposed with the type strain C264-GENT (=NCTC 14344T=DSM 110687T) and Mycoplasma phocoeninasale sp. nov. is proposed with the type strain C264-NAST (=NCTC 14343T=DSM 110688T) and representative strain CSL7498. The genome G+C contents are 24.06, 30.09, 28.49 and 29.05% and the complete genome sizes are 779 550, 815 486, 693 115, and 776 009 bp for strains ES2806-NAST, ES2806-GENT, C264-GENT and C264-NAST, respectively.

Streptococcus vicugnae sp. nov., isolated from faeces of alpacas (Vicugna pacos) and cattle (Bos taurus), Streptococcus zalophi sp. nov., and Streptococcus pacificus sp. nov., isolated from respiratory tract of California sea lions (Zalophus californianus).

Four novel independent strains of Streptococcus spp. were isolated from faeces of alpaca (SL1232T), cattle (KCJ4950), and from respiratory tract of wild California sea lions (CSL7508T, CSL7591T). The strains were indole-, oxidase- and catalase-negative, non-spore-forming, non-motile Gram-positive cocci in short and long chains, facultative anaerobes. The 16S rRNA gene of SL1232T and KCJ4950 shared 99.40-99.60% nucleotide similarity to strains of S. equinus, S. lutetiensis, S. infantarius, and the 16S rRNA gene of CSL7508T and CSL7591T demonstrated 98.72 and 98.92% similarity, respectively, to S. marimammalium. All other known Streptococcus species had the 16S rRNA gene sequence similarities of ≤95%. The genomes were sequenced for the novel strains. Average nucleotide identity (ANI) analysis for strains SL1232T and KCJ4950, showed the highest similarity to S. equinus, S. lutetiensis, and S. infantarius with 85.21, 87.17, 88.47, 85.54, 87.47 and 88.89%, respectively, and strains CSL7508T and CSL7591T to S. marimammalium with 87.16 and 83.97%, respectively. Results of ANI were confirmed by pairwise digital DNA-DNA hybridization and phylogeny, which also revealed that the strains belong to three novel species of the genus Streptococcus. Phenotypical features of the novel species were in congruence with closely related members of the genus Streptococcus and gave negative reactions with the tested Lancefield serological groups (A-D, F and G). MALDI-TOF mass spectrometry supported identification of the species. Based on these data, we propose three novel species of the genus Streptococcus, for which the name Streptococcus vicugnae sp. nov. is proposed with the type strain SL1232T (=NCTC 14341T=DSM 110741T=CCUG 74371T), Streptococcus zalophi sp. nov. is proposed with the type strain CSL7508T (=NCTC 14410T=DSM 110742T=CCUG 74374T) and Streptococcus pacificus sp. nov. is proposed with the type strain CSL7591T (=NCTC 14455T=DSM 111148T=CCUG 74655T). The genome G+C content is 36.89, 34.85, and 35.34 % and draft genome sizes are 1906993, 1581094 and 1656080 bp for strains SL1232T, CSL7508T, and CSL7591T, respectively.

Soil water-stable aggregates and microbial community under long-term tillage in black soil of Northern China.

Long-term frequent tillage would cause black soil degradation and serious soil erosion as soil microbial communities and soil structure are extremely sensitive to tillage process. However, there is no unified conclusion on the relationship between the distribution of soil water-stable aggregates (WSAs), and microbial community construction and diversity under long-term tillage in black soil during different seasons. In this study, we used wet-sieving method to evaluate the composition and stability of soil WSAs and employed Illumina MiSeq high-throughput sequencing technology to study the diversity, taxonomic composition and co-occurrence network properties of microbial community, comparing outcomes between uncultivated soil and long-term cultivated soil for 60 years in Keshan farm of Heilongjiang Province. The results showed that after long-term tillage, the proportion of larger than 1 mm WSAs reduced by 34.17-51.37%, and the stability of WSAs, soil pH, organic matter (OM), total nitrogen (TN) contents decreased significantly in all seasons (P < 0.05), while soil available phosphorus (AP) and available potassium (AK) contents increased remarkably (P < 0.05). The diversity of bacteria increased, while that of fungi decreased. Soil fungal communities were more susceptible to long-term tillage than bacterial and archaeal communities. Actinobacteria mainly exist in large WSAs (˃1 mm), and when their relative abundance is high, it is beneficial to improve the water-stability of black soil; while Proteobacteria and Gemmatimonadetes may exist in small WSAs (˂1 mm), whose high relative abundance will weaken the water-stability of black soil. The experimental results provide a scientific theoretical basis for sustainable utilization of black soil.

A Single Amino Acid Substitution at Residue 218 of Hemagglutinin Improves the Growth of Influenza A(H7N9) Candidate Vaccine Viruses.

The potential avian influenza pandemic remains a threat to public health, as the avian-origin influenza A(H7N9) virus has caused more than 1,560 laboratory-confirmed human infections since 2013, with nearly 40% mortality. Development of low-pathogenic candidate vaccine viruses (CVVs) for vaccine production is essential for pandemic preparedness. However, the suboptimal growth of CVVs in mammalian cells and chicken eggs is often a challenge. By introducing a single adaptive substitution, G218E, into the hemagglutinin (HA), we generated reassortant A(H7N9)-G218E CVVs that were characterized by significantly enhanced growth in both cells and eggs. These G218E CVVs retained the original antigenicity, as determined by a hemagglutination inhibition assay, and effectively protected ferrets from lethal challenge with the highly pathogenic parental virus. We found that the suboptimal replication of the parental H7 CVVs was associated with impeded progeny virus release as a result of strong HA receptor binding relative to weak neuraminidase (NA) cleavage of receptors. In contrast, the G218E-mediated growth improvement was attributed to relatively balanced HA and NA functions, resulted from reduced HA binding to both human- and avian-type receptors, and thus facilitated NA-mediated virus release. Our findings revealed that a single amino acid mutation at residue 218 of the HA improved the growth of A(H7N9) influenza virus by balancing HA and NA functions, shedding light on an alternative approach for optimizing certain influenza CVVs.IMPORTANCE The circulating avian influenza A(H7N9) has caused recurrent epidemic waves with high mortality in China since 2013, in which the alarming fifth wave crossing 2016 and 2017 was highlighted by a large number of human infections and the emergence of highly pathogenic avian influenza (HPAI) A(H7N9) strains in human cases. We generated low-pathogenic reassortant CVVs derived from the emerging A(H7N9) with improved virus replication and protein yield in both MDCK cells and eggs by introducing a single substitution, G218E, into HA, which was associated with reducing HA receptor binding and subsequently balancing HA-NA functions. The in vitro and in vivo experiments demonstrated comparable antigenicity of the G218E CVVs with that of their wild-type (WT) counterparts, and both the WT and the G218E CVVs fully protected ferrets from parental HPAI virus challenge. With high yield traits and the anticipated antigenicity, the G218E CVVs should benefit preparedness against the threat of an A(H7N9) influenza pandemic.

Ferroportin inhibition attenuates plasma iron, oxidant stress, and renal injury following red blood cell transfusion in guinea pigs.

BACKGROUND: Red blood cell (RBC) transfusions result in the sequestration and metabolism of storage-damaged RBCs within the spleen and liver. These events are followed by increased plasma iron concentrations that can contribute to oxidant stress and cellular injury. We hypothesized that administration of a ferroportin inhibitor (FPN-INH) immediately after acute RBC exchange transfusion could attenuate posttransfusion circulatory compartment iron exposure, by retaining iron in spleen and hepatic macrophages. STUDY DESIGN AND METHODS: Donor guinea pig blood was leukoreduced, and RBCs were preserved at 4°C. Recipient guinea pigs (n = 5/group) were exchange transfused with donor RBCs after refrigerator preservation and dosed intravenously with a small-molecule FPN-INH. Groups included transfusion with vehicle (saline), 5 mg/kg or 25 mg/kg FPN-INH. A time course of RBC morphology, plasma non-transferrin-bound iron (NTBI) and plasma hemoglobin (Hb) were evaluated. End-study spleen, liver, and kidney organ iron levels, as well as renal tissue oxidation and injury, were measured acutely (24-hr after transfusion). RESULTS: RBC transfusion increased plasma NTBI, with maximal concentrations occurring 8 hours after transfusion. Posttransfusion iron accumulation resulted in tubule oxidation and acute kidney injury. FPN inhibition increased spleen and liver parenchymal/macrophage iron accumulation, but attenuated plasma NTBI, and subsequent renal tissue oxidation/injury. CONCLUSION: In situations of acute RBC transfusion, minimizing circulatory NTBI exposure by FPN inhibition may attenuate organ-specific adverse consequences of iron exposure.

Acholeplasma equirhinis sp. nov. isolated from respiratory tract of horse (Equus caballus) and Mycoplasma procyoni sp. nov. isolated from oral cavity of raccoon (Procyon lotor).

We describe two novel species of Acholeplasma sp. strain N93 and Mycoplasma sp. strain LR5794 which were isolated from the nasopharynx of a horse from the United Kingdom and from the oral cavity of a North American raccoon from Canada, respectively. These strains were phenotypically and genetically characterized and compared to other established Mycoplasma and Acholeplasma species. Both strains are facultative anaerobes, resistant to penicillin, and produce acid from glucose but do not hydrolyze arginine and urea. Both strains grew well in microaerophilic and anaerobic atmospheric conditions at 35-37 °C using PPLO (pleuropneumonia-like organisms) medium. Acholeplasma sp. N93 does not require serum for growth. Colonies of both strains showed a typical fried-egg appearance and transmission electron microscopy of bacterial cells revealed a typical mycoplasma cellular morphology. Molecular characterization included assessment of several genetic loci. The genetic analysis indicated that Acholeplasma sp. N93 and Mycoplasma sp. LR5794 were most closely related to A. hippikon and A. equifetale, and M. molare and M. lagogenitalium, respectively. However, both novel strains were genetically unique in comparison to other well-known Mycoplasma and Acholeplasma species. Based on the isolation source history, phenotypic, genotypic, and phylogenetic characteristics of these novel strains, we propose the name Acholeplasma equirhinis sp. nov. for Acholeplasma sp. isolated from the nasopharynx of a horse [the type strain is N93T (= DSM 106692T = ATCC TSD-139T = NCTC 14351T)], and the name Mycoplasma procyoni sp. nov. for the Mycoplasma sp. isolated from the oral cavity of a North American raccoon [the type strain is LR5794T (= DSM 106703T = ATCC TSD-141T = NCTC 14309T)].

Ureaplasma miroungigenitalium sp. nov. isolated from northern elephant seals (Mirounga angustirostris) and Ureaplasma zalophigenitalium sp. nov. isolated from California sea lions (Zalophus californianus).

Novel ureaplasma strains have been isolated from the genital tract of both sexes of northern elephant seals (Mirounga angustirostris; six strains) and California sea lions (Zalophus californianus; five strains) stranded along the Central California coast, USA. These strains were phenotypically and genetically characterized and compared to other seven known Ureaplasma species. All novel ureaplasma strains hydrolysed urea, but did not metabolize arginine, and all were isolated and propagated using PPLO medium supplemented with urea under aerobic, microaerophilic, and anaerobic atmospheric conditions at +35-37 °C. Transmission electron microscopy revealed typical mollicute cellular morphology. Molecular characterization included assessment of the following genetic loci: 16S rRNA, the 16S-23S ITS, 23S rRNA, rpoB, ftsH, tufB, rpoC, fusA and ureC. Complete 16S rRNA gene sequence analysis of these novel Ureaplasma species indicated that they were most closely related to each other with nucleotide identity 99.87 % and ≤93.08 % related to other known Ureaplasma species. The results of nucleotide analysis of the sequenced housekeeping genes revealed 71.68-93.02 % similarity to corresponding genes of other known Ureaplasma species. The multi-locus genetic characterization and the phylogenetic analysis of the 16S rRNA and rpoB genes of these Ureaplasma species clearly demonstrated their novelty and, reflecting their host specificites, the name Ureaplasma miroungigenitalium sp. nov. is proposed for the Ureaplasma species isolated from northern elephant seals, the type strain is ES2783-GENT (=DSM 24842T=ATCC BAA-2460T), and the name Ureaplasma zalophigenitalium sp. nov. is proposed for the Ureaplasma species isolated from California sea lions, the type strain is CSL7644-GENT (=DSM 24843T=ATCC BAA-2262T).

Mycoplasma anserisalpingitidis sp. nov., isolated from European domestic geese (Anser anser domesticus) with reproductive pathology.

In 1983, Mycoplasma sp. strain 1220 was isolated in Hungary from the phallus lymph of a gander with phallus inflammation. Between 1983 and 2017, Mycoplasma sp. 1220 was also identified and isolated from the respiratory tract, liver, ovary, testis, peritoneum and cloaca of diseased geese in several countries. Seventeen studied strains produced acid from glucose and fructose but did not hydrolyse arginine or urea, and all grew under aerobic, microaerophilic and anaerobic conditions at 35 to 37 ˚C in either SP4 or pleuropneumonia-like organism medium supplemented with glucose and serum. Colonies on agar showed a typical fried-egg appearance and transmission electron microscopy revealed a typical mycoplasma cellular morphology. Molecular characterization included analysis of the following genetic loci: 16S rRNA, 23S rRNA, 16S-23S rRNA ITS, rpoB, rpoC, rpoD, uvrA, parC, topA, dnaE, fusA and pyk. The genome was sequenced for type strain 1220T. The 16S rRNA gene sequences of studied strains of Mycoplasma sp. 1220 shared 99.02-99.19 % nucleotide similarity with M. anatis strains but demonstrated ≤95.00-96.70 % nucleotide similarity to the 16S rRNA genes of other species of the genus Mycoplasma. Phylogenetic, average nucleotide and amino acid identity analyses revealed that the novel species was most closely related to Mycoplasma anatis. Based on the genetic data, we propose a novel species of the genus Mycoplasma, for which the name Mycoplasma anserisalpingitidis sp. nov. is proposed with the type strain 1220T (=ATCC BAA-2147T=NCTC 13513T=DSM 23982T). The G+C content is 26.70 mol%, genome size is 959110 bp.

Oceanivirga miroungae sp. nov., isolated from oral cavity of northern elephant seal (Mirounga angustirostris).

Two independent strains of a Leptotrichia species (ES3154-GLUT and ES2714_GLU) were isolated from the oral cavity of northern elephant seals (Mirounga angustirostris) that were admitted to The Marine Mammal Centre facilities in California, USA. The strains were isolated from oral swabs by cultivation in PPLO broth supplemented with serum, penicillin and colistin in anaerobic conditions. The strains were Gram-negative, pleomorphic, indole-, oxidase- and catalase-negative, non-spore-forming, non-motile rods/coccobacilli in short chains. The 16S rRNA gene sequence of these strains shared 94.42 % nucleotide similarity with Oceanivirga salmonicida AVG 2115T but demonstrated ≤86.00-92.50 % nucleotide similarity to the 16S rRNA genes of other species of the family Leptotrichiaceae. The genome was sequenced for strain ES3154-GLUT. Average nucleotide identity values between strain ES3154-GLUT and 15 type strain genomes from the family Leptotrichiaceae ranged from 66.74 % vs. Sebaldella termitidis to 73.35 % vs. O. salmonicida. The whole genome phylogeny revealed that the novel species was most closely related to O. salmonicida AVG 2115T. This relationship was also confirmed by nucleotide similarity and multilocus phylogenetic analyses employing various housekeeping genes (partial 23S rRNA, rpoB, rpoC, rpoD, polC, adh, gyrA and gyrB genes). Chemotaxonomic and phenotypical features of strain ES3154-GLUT were in congruence with closely related members of the family Leptotrichiaceae, represented by similar enzyme profiles and fatty acid patterns. MALDI-TOF MS analysis was capable to clearly discriminate strain ES3154-GLUT from all currently described taxa of the family Leptotrichiaceae. Based on these data, we propose a novel species of the genus Oceanivirga, for which the name Oceanivirga miroungae sp. nov. is proposed with the type strain ES3154-GLUT (=DSM 109740T=CCUG 73653T=ATCC TSD-189T=NCTC 14411T) and one representative strain ES2714_GLU. The G+C content is 26.82 %, genome size is 1 356 983 bp.

Evaluation on the effect of hydrogen sulfide on the NLRP3 signaling pathway and its involvement in the pathogenesis of atherosclerosis.

BACKGROUND: As a common disease, the incidence of atherosclerosis (AS) in the world is high. Therefore, we aimed to evaluate the involvement of hydrogen sulfide (H 2 S)/cystathionine γ-lyase (CSE) in the pathogenesis of AS as well as their possible signaling pathways. METHODS: Enzyme-linked immunosorbent assay, real-time polymerase chain reaction, and Western blot analysis were used to detect the effect of CSE on the expression of inflammatory cytokines, ie, H 2 S, thioredoxin-interacting protein (TXNIP), NLRP3, apoptosis-associated speck-like protein (ASC), caspase-1, and interleukin (IL)-1ß. In addition, immunohistochemistry and Western blot analysis were performed to detect the levels of TXNIP, NLRP3, ASC, caspase-1, IL-1ß, and IL-18 among different groups. RESULT: Knockdown of CSE by the transfection of CSE small interfering RNA upregulated the levels of two inflammatory cytokines, ie, IL-1ß and IL-18. In addition, the downregulation of CSE promoted the expression of TXNIP, NLRP3, ASC, caspase-1, and IL-1ß in THP-1 cells. Meanwhile, treating the cells with sodium hydrosulfide (NaHS) inhibited the productions of IL-1ß and IL-18. Furthermore, upregulation of H 2 S synthesis by treating the cells with NaHS also reduced the protein levels of TXNIP, NLRP3, ASC, caspase-1, and IL-1ß. Finally, the protein levels of TXNIP and NLRP3 in the AS group were much higher than those in the AS + H 2 S group, which in turn was higher than the sham group. In addition, the AS group displayed the highest protein levels of TXNIP, NLRP3, ASC, caspase-1, IL-1ß, and IL-18, while the levels of these proteins in the AS + H 2 S group were higher than those in the sham group. CONCLUSION: In summary, the present finding suggested a possible linkage between H 2 S metabolism and AS through the H 2 S/CSE-TXNIP-NLRP3-IL-18/IL-1ß-nitric oxide (NO) signaling pathway.

Comparison of the Efficacy of N9 Neuraminidase-Specific Monoclonal Antibodies against Influenza A(H7N9) Virus Infection.

The fifth wave of A(H7N9) virus infection in China from 2016 to 2017 caused great concern due to the large number of individuals infected, the isolation of drug-resistant viruses, and the emergence of highly pathogenic strains. Antibodies against neuraminidase (NA) provide added benefit to hemagglutinin-specific immunity and may be important contributors to the effectiveness of A(H7N9) vaccines. We generated a panel of mouse monoclonal antibodies (MAbs) to identify antigenic domains on NA of the novel A(H7N9) virus and compared their functional properties. The loop formed in the region of residue 250 (250 loop) and the domain formed by the loops containing residues 370, 400, and 430 were identified as major antigenic regions. MAbs 1E8, 2F6, 10F4, and 11B2, which recognize these two antigenic domains, were characterized in depth. These four MAbs differ in their abilities to inhibit cleavage of small and large substrates (methyl-umbelliferyl-acetyl neuraminic acid [MU-NANA] and fetuin, respectively) in NA inhibition assays. 1E8 and 11B2 did not inhibit NA cleavage of either MU-NANA or fetuin, and 2F6 inhibited cleavage of fetuin alone, whereas 10F4 inhibited cleavage of both substrates. All four MAbs reduced the in vitro spread of viruses carrying either the wild-type N9 or N9 with antiviral-resistant mutations but to different degrees. These MAbs have different in vivo levels of effectiveness: 10F4 was the most effective in protecting mice against challenge with A(H7N9) virus, 2F6 was less effective, and 11B2 failed to protect BALB/c mice at the doses tested. Our study confirms that NA-specific antibodies can protect against A(H7N9) infection and suggests that in vitro properties can be used to rank antibodies with therapeutic potential.IMPORTANCE The novel A(H7N9) viruses that emerged in China in 2013 continue to infect humans, with a high fatality rate. The most recent outbreak resulted in a larger number of human cases than previous epidemic waves. Due to the absence of a licensed vaccine and the emergence of drug-resistant viruses, there is a need to develop alternative approaches to prevent or treat A(H7N9) infection. We have made a panel of mouse monoclonal antibodies (MAbs) specific for neuraminidase (NA) of A(H7N9) viruses; some of these MAbs are effective in inhibiting viruses that are resistant to antivirals used to treat A(H7N9) patients. Binding avidity, inhibition of NA activity, and plaque formation correlated with the effectiveness of these MAbs to protect mice against lethal A(H7N9) virus challenge. This study identifies in vitro measures that can be used to predict the in vivo efficacy of NA-specific antibodies, providing a way to select MAbs for further therapeutic development.

Mycoplasma enhydrae sp. nov. isolated from southern sea otters (Enhydra lutris nereis).

Five Mycoplasma strains have been isolated from the oropharynx of southern sea otters (Enhydra lutris nereis) from the Central California Coast, USA. These strains were phenotypically and genetically characterized and compared to other established Mycoplasma species. All five strains hydrolysed arginine but not urea, but did not produce acid from glucose, and all were isolated and propagated under anaerobic and aerobic atmospheric conditions at +35-37 ˚C using either SP4 or PPLO medium supplemented with arginine. Colonies on solid medium showed a typical fried-egg appearance and transmission electron microscopy revealed a typical mycoplasma cellular morphology. Molecular characterization included assessment of the following genetic loci: 16S rRNA, 16S-23S rRNA ITS, rpoB, rpoC, polC, topIIA, tufB, arcA and smc. Complete 16S rRNA gene sequence analysis indicated that these strains were most closely related to M.ycoplasma phocicerebrale, and to M.ycoplasma arginini, M.ycoplasma gateae and M.ycoplasma canadense with nucleotide similarities of 99 and 98 %, respectively. Nucleotide analysis of other genetic loci revealed 73-91 % nucleotide similarity to the corresponding genes of the above closely related species. All five strains clustered into a distinct group on the 16S rRNA and rpoB phylogenetic trees. Serological testing via growth inhibition and metabolic inhibition tests employing antiserum to type strains of M. phocicerebrale, M. arginini, M. gateae and M. canadense failed to recognize these novel strains. Our results suggest that the strains isolated from southern sea otters represent a novel species of the genus Mycoplasma, for which the name Mycoplasma enhydrae sp. nov. is proposed; the type strain is 6243-11T (=DSM 106704T=ATCC TSD-140T).