Lactiplantibacillus brownii sp. nov., a novel psychrotolerant species isolated from sauerkraut.

A Gram-stain-positive, rod-shaped, facultatively anaerobic and homofermentative strain, named WILCCON 0030T, was isolated from sauerkraut (fermented cabbage) collected from a local market in the Moscow region of Russia. Comparative analyses based on 16S rRNA gene sequence similarity and whole genome relatedness indicated that strain WILCCON 0030T was most closely related to the type strains Lactiplantibacillus nangangensis NCIMB 15186T, Lactiplantibacillus daoliensis LMG 31171T and Lactiplantibacillus pingfangensis LMG 31176T. However, the average nucleotide identity and digital DNA-DNA hybridization prediction values with these closest relatives only ranged from 84.6 to 84.9 % and from 24.1 to 24.7 %, respectively, and were below the 95.0 and 70.0% thresholds for species delineation. Substantiated by further physiological and biochemical analyses, strain WILCCON 0030T represents a novel species within the genus Lactiplantibacillus for which we propose the name Lactiplantibacillus brownii sp. nov. (type strain WILCCON 0030T=DSM 116485T=LMG 33211T).

Mutual Exclusion of Methanobrevibacter Species in the Human Gut Microbiota Facilitates Directed Cultivation of a Candidatus Methanobrevibacter Intestini Representative.

Methanogenic Archaea (methanogens) are a phylogenetically diverse group of microorganisms and are considered to be the most abundant archaeal representatives in the human gut. However, the gut methanogen diversity of human populations in many global regions remains poorly investigated. Here, we report the abundance and diversity of gut methanogenic Archaea in a multi-ethnic cohort of healthy Singaporeans by using a concerted approach of metagenomic sequencing, 16S rRNA gene amplicon sequencing, and quantitative PCR. Our results indicate a mutual exclusion of Methanobrevibacter species, i.e., the highly prevalent Methanobrevibacter smithii and the less prevalent Candidatus Methanobrevibacter intestini in more than 80% of the samples when using an amplicon sequencing-based approach. Leveraging on this finding, we were able to select a fecal sample to isolate a representative strain, TLL-48-HuF1, for Candidatus Methanobrevibacter intestini. The analyzed physiological parameters of M. smithii DSM 861T and strain TLL-48-HuF1 suggest high similarity of the two species. Comparative genome analysis and the mutual exclusion of the Methanobrevibacter species indicate potentially different niche adaptation strategies in the human host, which may support the designation of Candidatus M. intestini as a novel species. IMPORTANCE Methanogens are important hydrogen consumers in the gut and are associated with differing host health. Here, we determine the prevalence and abundance of archaeal species in the guts of a multi-ethnic cohort of healthy Singapore residents. While Methanobrevibacter smithii is the most prevalent and abundant methanogen in the human gut of local subjects, the recently proposed Candidatus Methanobrevibacter intestini is the abundant methanogen in a minority of individuals that harbor them. The observed potential mutual exclusion of M. smithii and Ca. M. intestini provides further support to the proposal that the two physiologically similar strains may belong to different Methanobrevibacter species.

Effects of RANKL inhibition on promoting healing of bone erosion in rheumatoid arthritis using HR-pQCT: a 2-year, randomised, double-blind, placebo-controlled trial.

OBJECTIVE: To evaluate the effects of denosumab on erosion healing at 2-4 metacarpophalangeal (MCP) head as determined by high-resolution peripheral quantitative CT (HR-pQCT) in patients with rheumatoid arthritis (RA) with stable disease. METHODS: This was a randomised, placebo-controlled, double-blind study. Patients with RA with disease activity score 28 joints (DAS28) ≤5.1 were randomised (1:1) to subcutaneous denosumab 60 mg or placebo once every 6 months for 24 months. The primary outcome was erosion healing at MCP 2-4 on HR-pQCT at 12 months. The effects of denosumab on erosion and joint space parameters on HR-pQCT and radiographs, disease activity and health assessment questionnaire-disability index (HAQ-DI) were also examined. RESULTS: At 24 months, HR-pQCT images were analysed in 98 patients. One-third of the patients achieved sustained low disease activity throughout the study. At 12 months, changes in erosion parameters on HR-pQCT were similar between the two groups. At 24 months, new erosions (19% vs 9%, p=0.009) and erosion progression (18% vs 8%, p=0.019) were more common in the placebo group than the denosumab group. Erosion healing was seen in a significantly higher proportion of patients in the denosumab group (20% vs 6%, p=0.045) at 24 months. No significant changes in joint space parameters on HR-pQCT, van der Heijde-Sharp erosion score, DAS28 and HAQ-DI were observed in the two groups at 12 and 24 months. CONCLUSION: Although no differences in erosion parameters were observed at 12 months, denosumab was more efficacious than placebo in erosion repair on HR-pQCT after 24 months. TRIAL REGISTRATION NUMBER: NCT03239080.

DAPSA, carotid plaque and cardiovascular events in psoriatic arthritis: a longitudinal study.

OBJECTIVE: To examine whether Disease Activity in Psoriatic Arthritis (DAPSA) reflecting the inflammatory component of psoriatic arthritis (PsA) can predict cardiovascular (CV) events independent of traditional CV risk factors and subclinical carotid atherosclerosis. METHODS: A cohort analysis was performed in patients with PsA who had been followed since 2006. The outcome of interest was first CV event. Four different CV disease (CVD) risk scores and DAPSA were computed at baseline. The presence of carotid plaque (CP) and carotid intima-media thickness (CIMT) was also determined in a subgroup of patients using high-resolution ultrasound. The association between DAPSA, CVD risk scores, CP, CIMT and the occurrence of CV events was assessed using Cox proportional hazard models. RESULTS: 189 patients with PsA (mean age: 48.9 years; male: 104 (55.0%)) were recruited. After a median follow-up of 9.9 years, 27 (14.3%) patients developed a CV event. Higher DAPSA was significantly associated with an increased risk of developing CV events (HR: 1.04, 95% CI (1.01 to 1.08), p=0.009). The association remained significant after adjusting for all CV risk scores in the multivariable models. In the subgroup analysis, 154 patients underwent carotid ultrasound assessment and 23 (14.9%) of them experienced a CV event. CP was associated with increased risk of developing CV events after adjusting for three CV risk scores and DAPSA, with HR ranging from 2.35 to 3.42. CONCLUSION: Higher DAPSA and the presence of CP could independently predict CVD events in addition to traditional CV risk scores in patients with PsA.