Microfluidics-Derived Microparticles with Prebiotics and Probiotics for Enhanced In Situ Colonization and Immunoregulation of Colitis.

Oral administration of probiotics orchestrates the balance between intestinal microbes and the immune response. However, effective delivery and in situ colonization are limited by the harsh environment of the gastrointestinal tract. Herein, we provide a microfluidics-derived encapsulation strategy to address this problem. A novel synergistic delivery system composed of EcN Nissle 1917 and prebiotics, including alginate sodium and inulin gel, for treating inflammatory bowel disease and colitis-associated colorectal cancer is proposed. We demonstrated that EcN@AN microparticles yielded promising gastrointestinal resistance for on-demand probiotic delivery and colon-retentive capability. EcN@AN microparticles efficiently ameliorated intestinal inflammation and modulated the gut microbiome in experimental colitis. Moreover, the prebiotic composition of EcN@AN enhanced the fermentation of relative short-chain fatty acid metabolites, a kind of postbiotics, to exert anti-inflammatory and tumor-suppressive effects in murine models. This microfluidcis-based approach for the coordinated delivery of probiotics and prebiotics may have broad implications for gastrointestinal bacteriotherapy applications.

Comparison of endoscopic balloon dilation and surgery for duodenal stricture in patients with Crohn's disease.

BACKGROUND: Few studies have compared endoscopic balloon dilation (EBD) and surgery in the treatment of duodenal stricture in patients with Crohn's disease (CD). METHODS: We performed a retrospective study to compare the efficacy and safety among patients with CD-associated duodenal stricture treated with EBD or surgery from October 2013 to December 2021. Univariate and multivariate analyses were performed to evaluate factors associated with recurrence-free or surgery-free survival. RESULTS: A total of 48 eligible patients were included, including 30 patients treated with EBD only and 18 patients treated with surgery. Patients treated with surgery experienced more symptomatic improvement (100% vs. 63.33%, p = 0.003) and significantly longer recurrence-free survival (6.31 [IQR: 3.00-8.39] years vs. 2.96 [IQR: 1.06-5.42] years, p = 0.01) but suffered more postprocedural adverse events (16.67% vs. 0.74% per procedure, p = 0.001). In patients initially treated with EBD (n = 41), a total of 11 (26.83%) required subsequent surgical intervention. Younger age at CD diagnosis (HR = 0.90, 95% CI: 0.81-1.00, p = 0.04) was associated with a higher risk for subsequent surgery. CONCLUSIONS: Surgery for CD-associated duodenal strictures was associated with a longer recurrence-free survival. EBD was safe and effective with minimal postprocedural adverse events but led to a high frequency of recurrence.

Fingolimod Inhibits Exopolysaccharide Production and Regulates Relevant Genes to Eliminate the Biofilm of K. pneumoniae.

Klebsiella pneumoniae (K. pneumoniae) exhibits the ability to form biofilms as a means of adapting to its adverse surroundings. K. pneumoniae in this biofilm state demonstrates remarkable resistance, evades immune system attacks, and poses challenges for complete eradication, thereby complicating clinical anti-infection efforts. Moreover, the precise mechanisms governing biofilm formation and disruption remain elusive. Recent studies have discovered that fingolimod (FLD) exhibits biofilm properties against Gram-positive bacteria. Therefore, the antibiofilm properties of FLD were evaluated against multidrug-resistant (MDR) K. pneumoniae in this study. The antibiofilm activity of FLD against K. pneumoniae was assessed utilizing the Alamar Blue assay along with confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM), and crystal violet (CV) staining. The results showed that FLD effectively reduced biofilm formation, exopolysaccharide (EPS), motility, and bacterial abundance within K. pneumoniae biofilms without impeding its growth and metabolic activity. Furthermore, the inhibitory impact of FLD on the production of autoinducer-2 (AI-2) signaling molecules was identified, thereby demonstrating its notable anti-quorum sensing (QS) properties. The results of qRT-PCR analysis demonstrated that FLD significantly decreased the expression of genes associated with the efflux pump gene (AcrB, kexD, ketM, kdeA, and kpnE), outer membrane (OM) porin proteins (OmpK35, OmpK36), the quorum-sensing (QS) system (luxS), lipopolysaccharide (LPS) production (wzm), and EPS production (pgaA). Simultaneously, FLD exhibited evident antibacterial synergism, leading to an increased survival rate of G. mellonella infected with MDR K. pneumoniae. These findings suggested that FLD has substantial antibiofilm properties and synergistic antibacterial potential for colistin in treating K. pneumoniae infections.

A Nanoinhibitor Targeting cGAS-STING Pathway to Reverse the Homeostatic Imbalance of Inflammation in Psoriasis.

Psoriasis is a chronic skin inflammation characterized by dysregulated crosstalk between immune cells and keratinocytes. Here we show that the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway is a key regulator of psoriatic inflammation in a mouse model. Platinum-doped positively charged carbon dots (Pt-CDs) were designed to inhibit the cGAS-STING pathway. By inhibiting the cGAS-STING pathway with Pt-CDs, the secretion of proinflammatory cytokines in macrophages was reduced, and the proinflammatory cytokines-induced breakdown of immunological tolerance and overexpression of chemokines in keratinocytes was restored, which reversed the homeostatic imbalance through breaking these cytokines-mediated intercellular positive feedback loop. Topical Pt-CDs treatment exhibited therapeutic effects in imiquimod-induced psoriasis mice without noticeable toxicity. The reversal of elevated expression of STING, phosphorylated STING, and downstream genes within psoriatic lesions indicates that Pt-CDs effectively inhibit the cGAS-STING pathway. This work suggests a promising strategy for psoriasis treatment by targeting the cGAS-STING pathway with Pt-CDs nanoinhibitor to restore skin homeostatic balance.

Identification and genomic analysis of Pseudosulfitobacter koreense sp. nov. isolated from toxin-producing dinoflagellate Alexandrium pacificum.

The bacterial strain AP-MA-4T isolated from the marine dinoflagellate Alexandrium pacificum (KCTC AG60911), was subjected to a taxonomic analysis. Cells of strain AP-MA-4T were Gram-stain-negative, aerobic, rod-shaped, optimum growth at 20 °C, pH 7.0, in the presence of 5% (w/v) NaCl. Strain AP-MA-4T shared the highest 16S rRNA gene sequence similarity to Pseudosulfitobacter pseudonitzschiae DSM 26824T (98.5%), followed by Ascidiaceihabitans donghaensis RSS1-M3T (96.3%), Pseudoseohaeicola caenipelagi BS-W13T (95.7%), and Sulfitobacter pontiacus CHLG 10T (95.3%). Based on 16S rRNA phylogeny, strain AP-MA-4T is phylogenetically closely related to Pseudosulfitobacter pseudonitzschiae (type species of Pseudosulfitobacter) and could be distinguished from the type species based on their phenotypic properties. The genome length of strain AP-MA-4T was 3.48 Mbp with a 62.9% G + C content. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain AP-MA-4 T and its closely related type strains were 72.2-83.3 and 18.2-27.6%, respectively. Summed feature 8 (C18:1ω7c and/or C18:1ω6c) was identified the major fatty acids (> 10%). Phosphatidylglycerol (PG), phosphatidylethanolamine (PE), and phospholipid (PL) were demonstrated as the major polar lipids. The major respiratory quinone is ubiquinone-10 (Q-10). Based on genotypic and phenotypic features, strain AP-MA-4T (= KCTC 92289T = GDMCC 1.3585T) represents a new Pseudosulfitobacter species, in which the name Pseudosulfitobacter koreense sp. nov. is proposed.

Leisingera thetidis sp. nov., isolated from coastal water.

A Gram-strain-negative, strictly aerobic, rod-shaped, catalase-positive, oxidase-positive and pinkish beige colony-forming bacterial strain designated as BMJM1T was isolated from a marine sample collected from coastal water near Tongyeong, Republic of Korea. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that BMJM1T represents a member of the genus Leisingera as it is closely related to Leisingera daeponensis KCTC 12794T (98.27%), Leisingera caerulea DSM 24564T (97.98%), Leisingera aquaemixtae KCTC 32538T (97.91%), Leisingera methylohalidivorans DSM 14336T (97.26%) and Leisingera aquimarina DSM 24565T (97.25%). Optimal growth occurred at 25-30°C, pH 7.0 and with 2% NaCl. Digital DNA-DNA hybridisation (dDDH) and average nucleotide identity (ANI) values between strain BMJM1T and the closely related species of the genus Leisingera were below 40 and 90%, respectively, which are far below the thresholds to delineate a novel species. The predominant fatty acids (>10%) are summed feature 8 (C18:1ω7c and/or C18:1ω6c) (68.4%) and C14:1iso E (11.6%). The major polar lipids were phosphatidylethanolamine and phospholipid. The major isoprenoid quinone was ubiquinone-10. The DNA G+C content was 64.0%. On the basis of the results of the polyphasic taxonomic characterisation, BMJM1T represents a novel species of the genus Leisingera, for which the name is Leisingera thetidis sp. nov. is proposed, with that type strain BMJM1T (= KCTC 92110T = GDMCC 1.2992T).

Gymnodinialimonas phycosphaerae sp. nov., a phycosphere bacterium isolated from Karlodinium veneficum.

A facultative anaerobic, Gram-negative, non-motile, rod-shaped bacterial strain, designated N5T, was obtained from the phycosphere microbiota of the marine planktonic dinoflagellate, Karlodinium veneficum. Strain N5T showed growth on marine agar at 25 °C, pH 7 and 1 % (w/v) NaCl and produced a yellow colour. According to a phylogenetic study based on 16S rRNA gene sequences, strain N5T has a lineage within the genus Gymnodinialimonas. The G+C content in the genome of strain N5T is 62.9 mol% with a total length of 4 324 088 bp. The NCBI Prokaryotic Genome Annotation Pipeline revealed that the N5T genome contained 4230 protein-coding genes and 48 RNA genes, including a 5S rRNA, 16S rRNA, 23S rRNA, 42 tRNA, and three ncRNAs. Genome-based calculations (genome-to-genome distance, average nucleotide identity and DNA G+C content) clearly indicated that the isolate represents a novel species within the genus Gymnodinialimonas. The predominant fatty acids were C19 : 0 cyclo ω8c and feature 8 (comprising C18 : 1 ω6c and/or C18 : 1 ω7c). The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine and phosphatidylcholine. The main respiratory quinone was Q-10. Based on its phenotypic, phylogenetic, genomic and chemotaxonomic features, strain N5T represents a novel species of the genus Gymnodinialimonas, for which the name Gymnodinialimonas phycosphaerae sp. nov. is proposed. The type strain is N5T (=KCTC 82362T=NBRC 114899T).

Alkalimarinus alittae sp. nov., isolated from gut of marine sandworm (Alitta virens) and emended description of the genus Alkalimarinus.

A novel, Gram-stain-negative, aerobic, motile, catalase- and oxidase-negative bacterial strain, designated A2M4T, was isolated from the gut contents of a marine sandworm Alitta virens, collected from the eastern coast of the Republic of Korea. Strain A2M4T formed translucent circular colonies and showed rod-shaped cells with peritrichous flagella. Optimal growth of strain A2M4T occurred at 25 °C, pH 7.0 and in the presence of 2 % (w/v) NaCl. Phylogenetic analysis based on the 16S rRNA gene sequences showed that strain A2M4T was closely related to Alkalimarinus sediminis FA028T, with the highest sequence similarity of 98.9 %. The complete genome sequence of strain A2M4T was 4.25 Mbp in size and the genomic G+C content, calculated from the genome sequence, was 43.2 mol%. A comparison between the genome sequence of strain A2M4T and that of its closest relative, A. sediminis FA028T, showed an average nucleotide identity value of 76.63 % and a digital DNA-DNA hybridization value of 22.2 %. Strain A2M4T contained Q-9 as the sole respiratory isoprenoid quinone and the major polar lipids were phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine. The major cellular fatty acids of strain A2M4T were C14 : 0, C16 : 0 and summed feature 3 (comprising C16 : 1 ω7c and/or C16 : 1 ω6c). Based on its phenotypic, chemotaxonomic and genomic characteristics, strain A2M4T represents a novel species of the genus Alkalimarinus, for which the name Alkalimarinus alittae sp. nov. is proposed. The type is strain A2M4T (=KCTC 92030T=JCM 35924T). The description of the genus Alkalimarinus has also been emended.

Surgical Management and Outcome of Entero-Urinary Fistula Complicating Crohn's Disease: A Single Center Study.

BACKGROUND: Entero-urinary fistulas (EUF) are a rare complication of Crohn's disease (CD), observed in 1.6 to 7.7%. The management of EUF complicating CD is challenging. We aimed to report the outcome and surgical management of EUF in CD. METHODS: A retrospective chart review was performed in all CD patients with EUF who underwent surgery in our center between January 2012 and December 2021. Patient demographics, preoperative optimization, surgical management, postoperative complications, and follow-up information were collected from a prospectively maintained database. RESULTS: A total of 74 eligible patients were identified. The median interval between CD diagnosis and EUF diagnosis was 2 (0.08-6.29) years. Patients with EUF presented with pneumaturia (75.68%), urinary tract infections (72.97%), fecaluria (66.22%), and hematuria (6.76%). Fistulae originated most commonly from the ileum (63.51%), followed by the colon (14.86%), the rectum (9.46%), the cecum (2.70%), and multiple sites (9.46%). The EUF symptoms, weight, nutritional status, laboratory results were significantly improved after preoperative optimization. The absence of EUF symptoms was observed in 42 patients after the optimization and only 9 of which required bladder repair. However, 19 of 32 patients whose symptoms did not resolve required bladder repair (P = 0.001). Only 1 patient developed a bladder leakage in the early postoperative period and 3 patients experienced recurrent bladder fistula. CONCLUSIONS: Surgical management of EUF complicating CD is effective and safe, with a low rate of postoperative complication and EUF recurrence. Preoperative optimization, which is associated with the resolution of urinary symptoms and improved surgical outcomes, should be recommended.

Emticicia fluvialis sp. nov., a potential hormone-degrading bacterium isolated from Nakdong River, Republic of Korea.

A novel species of the genus Emticicia, designated BHSR1T, was isolated from a water sample that was collected from the Nakdong River, Republic of Korea, and its taxonomic affiliation was studied using a polyphasic approach. This bacterium was Gram-stain-negative, non-motile, aerobic, curved, rod-shaped, and oxidase- and catalase-negative. The bacterium grew optimally at 37 °C, pH 7.5 and 0% (w/v) NaCl. Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain BHSR1T should be affiliated with the genus Emticicia, with a high similarity to Emticicia fontis KCTC 52248T (98.10%). Phylogenomic analysis also suggested that the strain represents a novel species in the genus Emticicia. The genomic G + C content was 41.9%. The average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization between strain BHSR1T and its closely related relatives in the genus Emticicia were in ranges of 71.1-75.8%, 69.4-77.5% and 18.6-19.9%, respectively. The gene cluster within BHSR1T contained genes encoding enzymes that could be involved in hormone degradation. The major cellular fatty acids (> 10%) were summed feature 3 (comprising C16:1ω6c and/or C16:1ω7c) and iso-C15:0. With regards to the polar lipid profile, phosphatidylethanolamine (PE), two unidentified aminolipids and three unidentified lipids were identified as the major compounds. The major respiratory quinone was menaquinone (MK)-7. Based on its phylogenetic, phenotypic, chemotaxonomic, and genomic features, strain BHSR1T should be considered a novel species in the genus Emticicia of the family Spirosomaceae, for which the name Emticicia fluvialis sp. nov. is proposed. The type strain was considered BHSR1T (= KCTC 92622T = GDMCC 1.3740T).

Gymnodinialimonas ceratoperidinii gen. nov., sp. nov., isolated from rare marine dinoflagellate Ceratoperidinium margalefii.

A bacterial strain, designated J12C1-MA-4T, was isolated from liquid culture of the dinoflagellate Ceratoperidinium margalefii. The bacterium was Gram-negative, aerobic, and rod-shaped. Oxidase and catalase were positive. Optimal growth was observed at 30 °C, pH 7.0, in the presence of 1% (w/v) NaCl. Phylogenetic analyses based on 16S rRNA gene and a 92 core gene set suggested that the strain J12C1-MA-4T belongs to the family Rhodobacteraceae in the class Alphaproteobacteria and represents a taxon separated from other genera. 16S rRNA gene sequence of the strain J12C1-MA-4T showed high similarities to Loktanella ponticola KCTC 42133T (95.7%), Pseudooctadecabacter jejudonensis KCTC 32525T (95.5%) and Jannaschia helgolandensis KCTC 12191T (95.3%). The genome length of strain J12C1-MA-4T was 3,621,968 bp with a DNA G + C content of 64.48 mol%. The major cellular fatty acids of strain J12C1-MA-4T were summed feature 8 (comprising C18:1ω7c and/or C18:1ω6c) (> 10%). Phosphatidylglycerol (PG), phosphatidylcholine (PC), phospholipids (PL), lipids 1 (L1) and aminolipid (AL) were shown to be the major polar lipids. The sole predominant isoprenoid quinone was Q-10. Based on phylogenetic, phenotypic, chemotaxonomic and genomic features, we propose that strain J12C1-MA-4T represent a novel species in the novel genus of the family Rhodobacteraceae, with the proposed name Gymnodinialimonas ceratoperidinii gen. nov., sp. nov.. The type strain is J12C1-MA-4T (=KCTC 82770T =GDMCC 1.2729T).

Olsenella intestinalis sp. nov., isolated from cow feces.

A Gram-stain-negative, anaerobic, non-motile, rod-shaped bacterium, designated as BGYT1T, was isolated from the feces of a cow in Andong, Republic of Korea. It was studied using a polyphasic method to determine its taxonomic position. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain BGYT1T formed a lineage within the genus Olsenella and was most closely related to O. umbonate KCTC 15140T (98.2%). The complete genome sequence of strain BGYT1T was 2,476,083 bp long with a G + C content of 66.9 mol% and contained 1835 genes and 8 contigs. The N50 value was 604,117 bp. There were 50 tRNAs, 6 rRNAs (5S, 16S, 23S), 1778 CDSs and 2 BGCs and 1 tmRNA. The values for ANI (76.8%), AAI (67.3%), and dDDH (22.2%) compared to the closest related species were all below the threshold for bacterial species delineation. In addition, genes encoding the cell wall degrading enzymes such as chitinases, ß-1,3 glucanases, and proteases were also detected. The strain was able to grow at pH 6.0-8.0 (optimum, pH 7.0), in the presence of 0.5-1.5% NaCl (optimum, 0.5%, w/v) and at the temperature range of 35-40 °C (optimum, 35 °C). The predominant fatty acids were C16:0 DMA (20.2%), C16:0 (20.2%), C18:0 (10.5%) and C18:1 cis 9 (17.0%). The polar lipids consisted of an unidentified phospholipid, four unidentified glycolipids and three unidentified lipids. Based on its phenotypic analyses, phylogenetic and physiological characteristics, strain BGYT1T represented a novel species within the genus Olsenella, for which the name Olsenella intestinalis sp. nov. is proposed. The type strain is BGYT1T (= KCTC 25379T = GDMCC 1.3011T).

Cellulosimicrobium protaetiae sp. nov., isolated from the gut of the larva of Protaetia brevitarsis seulensis.

A Gram-stain-positive, non-spore-forming, yellow-pigmented, non-motile, non-flagellated, facultative anaerobic and rod-shaped bacterial strain, designated BI34T, was isolated from the gut of the larva of Protaetia brevitarsis seulensis. Strain BI34T grew at 15-40 °C (optimum, 37 °C), at pH 6.5-9.0 (optimum, pH 7.5) and in the presence of 0-7 % (w/v) NaCl (optimum, 2 %). Based on the results of 16S rRNA gene sequence analysis, strain BI34T belonged to the phylum Actinobacteria and was closely related to Cellulosimicrobium funkei NBRC 104118T (99.3 %), Cellulosimicrobium cellulans NBRC 15516T (99.1 %), Cellulosimicrobium composti BIT-GX5T (99.0 %), Cellulosimicrobium fucosivorans SE3T (99.0 %), Cellulosimicrobium marinum NBRC 110994T (98.4 %) and Cellulosimicrobium terreum DS-61T (97.0 %). The genome to genome relatedness of the average nucleotide identity (ANI) and the digital DNA-DNA hybridization (dDDH) values calculated by the Genome-to-Genome Distance Calculator between strain BI34T and its related species mentioned above were lower than the threshold of 95 and 70 % for speciation, respectively. The predominant menaquinone of strain BI34T contained MK-9(H4), and the major fatty acids were anteiso-C15 : 0, C16 : 0 and anteiso-C17 : 0. Strain BI34T had diphosphatidylglycerol and phosphatidylglycerol as major polar lipids. The whole-cell sugars were galactose, glucose and ribose, and the cell-wall peptidoglycan contained lysine, alanine, aspartic acid and glutamic acid. The DNA G+C content of strain BI34T was 73.8 mol%. The difference in physiological and biochemical characteristics and the below-threshold values of genome-to-genome relatedness indicate that strain BI34T represents a novel species in the genus Cellulosimicrobium, for which the name Cellulosimicrobium protaetiae sp. nov. is proposed. The type strain is BI34T (=KCTC 49302T=NBRC 114073T).

Pseudophaeobacter flagellatus sp. nov., isolated from coastal water.

A Gram-stain-negative, aerobic, motile, rod-shaped novel bacterial strain, designated as MA21411-1T, was isolated from the Korean coast. The colonies were white-yellow-coloured, smooth, convex and entire, spherical and 1.0-1.8 mm in diameter. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain MA21411-1T is closely related to species of the genus Pseudophaeobacter. The 16S rRNA gene sequence similarities between strain MA21411-1T and Pseudophaeobacter arcticus DSM 23566T, Phaeobacter porticola DSM 103148T and Pseudophaeobacter leonis DSM 25627T were 98.31, 97.80 and 97.28 %, respectively. Strain MA21411-1T has a draft genome size of 4 294 042 bp, annotated with 4125 protein-coding genes, and 53 tRNA, three rRNA and one tmRNA genes. The genomic DNA G+C content was 59.2 mol%. Comparative genome analysis revealed that the average nucleotide identity, digital DNA-DNA hybridization and average amino acid identity values among strain MA21411-1T and other related species were below the cut-off levels of 95, 70 and 95.5 %, respectively. The growth temperature range for growth was 15-28 °C (optimum, 25 °C), pH range was 6.0-9.0 (optimum, pH 6.0), and salt tolerance range was 0.5-4 % (optimum 0.5 %). Ubiquinone-10 was the sole quinone present in MA21411-1T and all three closely related strains. The major cellular fatty acid (>10 %) of the strain was summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c). The polar lipid profile contained phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and four unidentified polar lipids. Based on the phylogenetic tree, as well as phenotypic, chemotaxonomic and genomic features, strain MA21411-1T represents a novel species of the genus Pseudophaeobacter, for which the name Pseudophaeobacter flagellatus sp. nov. is proposed. The type strain is MA21411-1T (=KCTC 92095T=GDMCC 1.2988T).

Halorubrum salinarum sp. nov., an extremely halophilic archaeon isolated from a saturated brine pond of a saltern.

A novel extremely halophilic archaeon, strain RHB-CT, was isolated from a saturated brine pond of a solar saltern in Bolinao, Pangasinan, Philippines. Colonies were orange-red-pigmented, smooth, convex and round on a solid modified growth medium containing 25 % (w/v) of total salts. Cells of strain RHB-CT on the solid modified growth medium were ovoid-shaped (0.89-2.66 µm long), while the cells in a liquid modified growth medium were rod-shaped (1.53-5.65 µm long and 0.45-1.03 µm wide). The strain was Gram-stain-negative, motile and strictly aerobic. Strain RHB-CT grew with NaCl concentrations ranging from 10 to 30 % (w/v; optimum, 20-25 %), at pH 6.5-8.5 (optimum, pH 7.0-7.5) and at 20-55 °C (optimum, 40-45 °C). Furthermore, the strain grew even in the absence of Mg2+; however, when supplemented with Mg2+, growth was observed optimally at 0.2-0.4 M Mg2+. The 16S rRNA gene phylogeny inferred that the strain is a member of the genus Halorubrum and was related to Halorubrum xinjiangense CGMCC 1.3527T (99.0 %), Halorubrum sodomense DSM 3755T (98.8 %), Halorubrum coriense Ch2T (98.8 %), Halorubrum trapanicum NRC 34021T (98.4 %) and Halorubrum distributum JCM 9100T (98.1 %). The rpoB' gene sequences also showed that strain RHB-CT is related to Hrr. xinjiangense JCM 12388T (97.1 %), Hrr. distributum JCM 9100T (97.1 %), Hrr. coriense JCM 9275T (96.5 %), Hrr. californiense JCM 14715T (96.5 %), Hrr. trapanicum JCM 10477T (96.3%), Hrr. sodomense JCM 8880T (96.2%) and Hrr. tebenquichense DSM 14210T (95.6 %). The DNA G+C content of strain RHB-CT was 68.7 mol% (genome). Digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values between strain RHB-CT and the closely related species of Halorubrum were below 40 and 90 %, respectively, which are far below the thresholds to delineate a new species. The polar lipids of strain RHB-CT were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulphate and sulfated mannosyl glycosyl diether. Based on dDDH and ANI values, and the significant morphological and physiological differences from known taxa, it is hereby suggested that strain RHB-CT represents a novel species of the genus Halorubrum, for which the name Halorubrum salinarum sp. nov. is proposed. The type strain is RHB-CT (=KCTC 4274T=CMS 2103T).

Sphingomonas cannabina sp. nov., isolated from Cannabis sativa L. 'Cheungsam'.

A Gram-negative, aerobic, rod-shaped bacterium, designated DM2-R-LB4T was isolated from Cannabis sativa L. 'Cheungsam' in Andong, Republic of Korea. The strain DM2-R-LB4T grew at temperatures of 15-45 °C (optimum, 30-37 °C), pH of 5.5-9 (optimum, 8.0), and 0-2 % (w/v) NaCl concentration (optimum, 0%). Phylogenetic analyses based on the 16S rRNA gene sequences revealed that strain DM2-R-LB4T is related to species of the genus Sphingomonas, and shared 97.8 and 97.5% similarity to Sphingomonas kyenggiensis KCTC 42244T and Sphingomonas leidyi DSM 4733T, respectively. The DNA G+C content was 67.9 mol% and genome analysis of the strain DM2-R-LB4T revealed that the genome size was 4 386 171 bp and contained 4 009 predicted protein-coding genes. The average nucleotide identity (ANI) values between strain DM2-R-LB4T and S. kyenggiensis KCTC 42244T, and S. leidyi DSM 4733T was 76.8 and 76.7 %, respectively, while the values of digital DNA-DNA hybridization (dDDH) were 20.7 and 20.6 %, respectively. C14 : 0 2-OH, C16 : 0, and summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c) were the major fatty acids (>10 %) in the strain DM2-R-LB4T. The polar lipids comprised diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylcholine (PC), sphingoglycolipid (SGL), glycolipid (GL), phospholipid (PL), and two unidentified polar lipids (L1 and L2). Ubiquinone-10 (Q-10) was the only respiratory quinone. The polyamine pattern was found to contain homospermidine, putrescine, and spermidine. The results of phylogenetic anlayses, polyphasic studies, revealed that strain DM2-R-LB4T represents a novel species of the genus Sphingomonas, for which the name Sphingomonas cannabina sp. nov., is proposed. The type strain is DM2-R-LB4T (=KCTC 92075T = GDMCC 1.3018T).

Unraveling the Gonyaulax baltica Species Complex: Cyst-theca Relationship of Impagidinium variaseptum, Spiniferites pseudodelicatus sp. nov. and S. ristingensis (Gonyaulacaceae, Dinophyceae), With Descriptions of Gonyaulax bohaiensis sp. nov, G. amoyensis sp. nov. and G. portimonensis sp. nov.

The taxonomy of the extant dinoflagellate genus Gonyaulax is challenging since its thecate morphology is rather conservative. In contrast, cysts of Gonyaulax are varied in morphology and have been related with the fossil-based genera Spiniferites and Impagidinium. To better understand the systematics of Gonyaulax species, we performed germination experiments on cysts that can be identified as S. ristingensis, an unidentified Spiniferites with petaloid processes here described as Spiniferites pseudodelicatus sp. nov. and Impagidinium variaseptum from Chinese and Portuguese waters. Despite marked differences in cyst morphology, motile cells of S. pseudodelicatus and I. variaseptum are indistinguishable from Gonyaulax baltica. Motile cells hatched from S. ristingensis are morphologically similar to G. baltica as well but differ in the presence of one pronounced antapical spine. Three new species, Gonyaulax amoyensis (cyst equivalent S. pseudodelicatus), Gonyaulax bohaiensis (cyst equivalent I. variaseptum), and Gonyaulax portimonensis (cyst equivalent S. ristingensis), were erected. In addition, a new ribotype (B) of G. baltica was reported from South Korea and a bloom of G. baltica ribotype B is reported from New Zealand. Molecular phylogeny based on LSU and SSU rRNA gene sequences revealed that Gonyaulax species with minute or short antapical spines formed a well-resolved clade, whereas species with two pronounced antapical spines or lack of antapical spines formed the sister clade. Six strains of four above species were examined for yessotoxin production by liquid chromatography coupled with tandem mass spectrometry, and very low concentrations of yessotoxin were detected for one G. bohaiensis strain.

The rates and medical necessity of cesarean delivery in China, 2012-2019: an inspiration from Jiangsu.

BACKGROUND: The World Health Organization (WHO) in 2015 stated that every effort should be made to provide cesarean delivery (CD) for women in need. In China, the two-child policy largely prompts the number of advanced age childbirth, which raises the possibility of an increasing number of women who need a c-section. The aim of this study was to assess the trends in the overall and medical indication-classified CD rates in the era of the two-child policy in Jiangsu, China. METHODS: A retrospective cross-sectional study of 291,448 women who delivered in 11 hospitals in Jiangsu province between 2012 and 2019 was conducted. Medical cesarean indication for each woman was ascertained by manually reviewing the medical records. The 291,448 women were divided into two subgroups according to the presence of the indications: the indicated group (7.80%) and the non-indicated group (92.20%). We then fitted joinpoint regression and log-binomial regression models to estimate trends in the CD rates across the study period. RESULTS: The overall CD rate was observed with a declining trend from 52.51% in 2012-2015 to 49.76% in 2016-2019 (adjusted RR, 0.92; 95% CI, 0.91-0.93; P < 0.001), along with an annual percentage change (APC) to be - 1.0 (95% CI, - 2.1 to 0.0) across the period. The participants were then divided into two subgroups according to the presence of medical CD indications: the indicated group (7.80%) and the non-indicated group (92.20%).We found the declining trend was most pronounced in the non-indicated group, with the CD rates decreased from 50.02% in 2012-2015 to 46.27% in 2016-2019 (adjusted RR, 0.90; 95% CI, 0.89-0.90; P < 0.001). By contrast, we observed a steady trend in the CD rate of the indicated group, which maintained from 87.47% in 2012-2015 to 86.57% in 2016-2019 (P = 0.448). In the indicated group, a higher risk of adverse pregnancy outcomes was revealed for those women who delivered vaginally as compared with those who received c-section. We further investigated that women with following specific indications had a higher proportion of vaginal delivery, i.e., pregnancy complications, fetal macrosomia, and pregnancy complicated with tumor (34.70%, 10.84%, and 16.34%, respectively). Women with the above 3 indications were observed with a higher risk of adverse pregnancy outcomes if delivered vaginally. The incidence rates of the medical indications among the general population increased considerably over the 8-year period (P < 0.001). CONCLUSIONS: Although the overall CD rate apparently decreased in the recent years, along with the decline of the unnecessary CD rate, a considerable proportion of indicated women were not provided with CD service in Jiangsu, China. Instead of targeting the overall CD rate, we need to take actions to reduce unnecessary CD rate and provide adequate c-section service for women with indications, particularly for those with underlying diseases and suspected fetal macrosomia.

Flagellatimonas centrodinii gen. nov., sp. nov., a novel member of the family Nevskiaceae isolated from toxin-producing dinoflagellate Centrodinium punctatum.

A Gram-stain-negative, aerobic, rod-shaped strain (R2A-3T) was isolated from the toxin-producing dinoflagellate Centrodinium punctatum and identified as a novel genus and new species based on a polyphasic taxonomic approach. The optimum conditions for growth of the strain were at 25 °C, pH 8.0 and in the presence of 3 % (w/v) NaCl. Phylogenetic analyses based on 16S rRNA genes and 92 core genes sets revealed that strain R2A-3T belongs to the family Nevskiaceae in the class Gammaproteobacteria and represented an independent taxon separated from other genera. The 16S rRNA gene of strain R2A-3T showed the highest sequence similarity to Polycyclovorans algicola TG408T (95.2%), Fontimonas thermophila HA-01T (94.1%) and Sinimarinibacterium flocculans NH6-24T (93.2%), and less than 92.8 % similarity to other genera in the family Nevskiaceae. The genome length of strain R2A-3T was 3608892 bp with 65.2 mol% G+C content. Summed feature 8 (comprising C18 : 1 ω7c and/or C18 : 1 ω6c) was the major fatty acid (>10 %). Diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine were detected as the major polar lipids. The major respiratory quinone was ubiquinone-8. According to its phylogenetic, phenotypic, chemotaxonomic and genomic features, strain R2A-3T represents a new species in the new genus of the family Nevskiaceae. It is recommended to name it Flagellatimonas centrodinii gen. nov., sp. nov. The type strain is R2A-3T (=KCTC 82469T=GDMCC 1.2523T).

Pedobacter endophyticus sp. nov., an endophytic bacterium isolated from Carex pumila.

An aerobic, Gram-stain-negative, weak-motile, short-rod-shaped bacterial strain, designated JBR3-12T, was isolated from halophyte Carex pumila plants, and its taxonomic position was investigated by using a polyphasic taxonomic approach. The strain produced a pink pigment on tryptic soy agar and grew optimally at 25 °C, pH 8 and in the presence of 3 % (w/v) NaCl. Results of phylogenetic analysis based on 16S rRNA gene sequences showed that strain JBR3-12T formed a lineage within the genus Pedobacter and was most closely related to Pedobacter sandarakinus DS-27T (98.0 %) and Pedobacter agri PB92T (97.6 %). The DNA G+C content of the genome was 41.3 mol%; the whole genome length was 5 426 070 bp. The major fatty acids of JBR3-12T were iso-C15 : 0, summed feature 3 (comprising C16 : 1 ω6c and/or C16 : 1 ω7c) and iso-C17 : 0 3-OH. The predominant polar lipid was phosphatidylethanolamine. The predominant quinone was menaquinone-7. Based on its phenotypic, phylogenetic and genotypic features, strain JBR3-12T is proposed to represent a novel species of the genus Pedobacter, for which the name is Pedobacter endophyticus sp. nov. The type strain is JBR3-12T (=KCTC 82363T=NBRC 114901T).