Devosia aquimaris sp. nov., isolated from seawater of the Changjiang River estuary of China.

A gram-stain-negative, aerobic, rod-shaped bacterium strain CJK-A8-3T was isolated from a polyamine-enriched seawater sample collected from the Changjiang River estuary of China. The colonies were white and circular. Strain CJK-A8-3T grew optimally at 35 °C, pH 7.0 and 1.5% NaCl. Its polar lipids contained phosphatidylglycerol, phosphatidic acid, unidentified glycolipids, and a combination of phospholipids and glycolipids. The respiratory quinone was ubiquinone-10, and its main fatty acids were C16:0, 11-methyl C18:1ω7c and Summed Feature 8 (including C18:1ω7c/C18:1ω6c). The phylogenetic tree based on 16S rRNA genes placed strain CJK-A8-3T in a new linage within the genus Devosia. 16S rRNA gene sequence of strain CJK-A8-3T showed identities of 98.50% with Devosia beringensis S02T, 98.15% with D. oryziradicis, and 98.01% with D. submarina JCM 18935T. The genome size of strain CJK-A8-3T was 3.81 Mb with the DNA G + C content 63.9%, higher than those of the reference strains (60.4-63.8%). The genome contained genes functional in the metabolism of terrigenous aromatic compounds, alkylphosphonate and organic nitrogen, potentially beneficial for nutrient acquirement and environmental remediation. It also harbored genes functional in antibiotics resistance and balance of osmotic pressure, enhancing their adaptation to estuarine environments. Both genomic investigation and experimental verification showed that strain CJK-A8-3T could be versatile and efficient to use diverse organic nitrogen compounds as carbon and nitrogen sources. Based on phenotypic, chemotaxonomic, phylogenetic and genomic characteristics, strain CJK-A8-3T was identified as a novel Devosia species, named as Devosia aquimaris sp. nov. The type strain is CJK-A8-3T (= MCCC 1K06953T = KCTC 92162T).

Is mechanical bowel preparation mandatory for elective colon surgery? A systematic review and meta-analysis.

BACKGROUND: Growing evidence demonstrates minimal impact of mechanical bowel preparation (MBP) on reducing postoperative complications following elective colectomy. This study investigated the necessity of MBP prior to elective colonic resection. METHOD: A systematic literature review was conducted across PubMed, Ovid, and the Cochrane Library to identify studies comparing the effects of MBP with no preparation before elective colectomy, up until May 26, 2023. Surgical-related outcomes were compiled and subsequently analyzed. The primary outcomes included the incidence of anastomosis leakage (AL) and surgical site infection (SSI), analyzed using Review Manager Software (v 5.3). RESULTS: The analysis included 14 studies, comprising seven RCTs with 5146 participants. Demographic information was consistent across groups. No significant differences were found between the groups in terms of AL ((P = 0.43, OR = 1.16, 95% CI (0.80, 1.68), I2 = 0%) or SSI (P = 0.47, OR = 1.20, 95% CI (0.73, 1.96), I2 = 0%), nor were there significant differences in other outcomes. Subgroup analysis on oral antibiotic use showed no significant changes in results. However, in cases of right colectomy, the group without preparation showed a significantly lower incidence of SSI (P = 0.01, OR = 0.52, 95% CI (0.31, 0.86), I2 = 1%). No significant differences were found in other subgroup analyses. CONCLUSION: The current evidence robustly indicates that MBP before elective colectomy does not confer significant benefits in reducing postoperative complications. Therefore, it is justified to forego MBP prior to elective colectomy, irrespective of tumor location.

Biodegradation of low-density polyethylene film by two bacteria isolated from plastic debris in coastal beach.

Low-density polyethylene (LDPE) conduces massive environmental accumulation due to its high production and recalcitrance to environment. In this study, We successfully enriched and isolated two strains, Nitratireductor sp. Z-1 and Gordonia sp. Z-2, from coastal plastic debris capable of degrading LDPE film. After a 30-day incubation at 30 ℃, strains Z-1 and Z-2 decreased the weight of branched-LDPE (BLDPE) film by 2.59 % and 10.27 % respectively. Furthermore, high temperature gel permeation chromatography (HT-GPC) analysis revealed molecular weight reductions of 7.69 % (Z-1) and 23.22 % (Z-2) in the BLDPE film. Scanning electron microscope (SEM) image showed the presence of microbial colonization and perforations on the film's surface. Fourier transform infrared spectroscopy (FTIR) analysis indicated novel functional groups, such as carbonyl and carbon-carbon double bonds in LDPE films. During LDPE degradation, both strains produced extracellular reactive oxygen species (ROS). GC-MS analysis revealed the degradation products included short-chain alkanes, alkanols, fatty acids, and esters. Genomic analysis identified numerous extracellular enzymes potentially involved in LDPE chain scission. A model was proposed suggesting a coordinated role between ROS and extracellular enzymes in the biodegradation of LDPE. This indicates strains Z-1 and Z-2 can degrade LDPE, providing a basis for deeper exploration of biodegradation mechanisms.

Genomic characteristics of nine Nitrospirota metagenome-assembled genomes in deep-sea sediments from East Pacific polymetallic nodules zone.

Previously studies have reported that MAGs (Metagenome-assembled genomes) belong to "Candidatus Manganitrophaceae" of phylum Nitrospirota with chemolithoautotrophic manganese oxidation potential exist in freshwater and hydrothermal environments. However, Nitrospirota members with chemolithoautotrophic manganese oxidation potential have not been reported in other marine environments. Through metagenomic sequencing, assembly and binning, nine metagenome-assembled genomes belonging to Nitrospirota are recovered from sediment of different depths in the polymetallic nodule area. Through the key functional genes annotation results, we find that these Nitrospirota have limited potential to oxidize organic carbon because of incomplete tricarboxylic acid cycle and most of them (6/9) have carbon dioxide fixation potential through different pathway (rTCA, WL or CBB). One MAG belongs to order Nitrospirales has the potential to use manganese oxidation to obtain energy for carbon fixation. In addition to manganese ions, the oxidation of inorganic nitrogen, sulfur, hydrogen and carbon monoxide may also provide energy for the growth of these Nitrospirota. In addition, different metal ion transport systems can help those Nitrospirota to resist heavy metal in sediment. Our work expands the understanding of the metabolic potential of Nitrospirota in sediment of polymetallic nodule region and may contributes to promoting the study of chemolithoautotrophic manganese oxidation.

Risk factor evaluation of cuff pressure of >30 cmH2O to stop air leakage during mechanical ventilation: A prospective observational study.

AIM: The commonly recommended endotracheal tube cuff pressure is 20-30 cmH2O. However, some patients require a cuff pressure of >30 cmH2O to prevent air leakage. The study aims to determine the risk factors that contribute to the endotracheal tube cuff pressure of >30 cmH2O to prevent air leakage. DESIGN: A multi-centre prospective observational study. METHODS: Eligible patients undergoing mechanical ventilation in the intensive care unit of three hospitals between March 2020 and July 2022 were included. The endotracheal tube cuff pressure to prevent air leakage was determined using the minimal occlusive volume technique. The patient demographics and clinical information were collected. RESULTS: A total of 284 patients were included. Among these patients, 55 (19.37%) patients required a cuff pressure of >30 cmH2O to prevent air leakage. The multivariate logistic regression results revealed that the surgical operation (odds ratio [OR]: 8.485, 95% confidence interval [CI]: 1.066-67.525, p = 0.043) was inversely associated with the endotracheal tube cuff pressure of >30 cmH2O, while the oral intubation route (OR: 0.127, 95% CI: 0.022-0.750, p = 0.023) and cuff inner diameter minus tracheal area (OR: 0.949, 95% CI: 0.933-0.966, p < 0.001) were negatively associated with the endotracheal tube cuff pressure of >30 cmH2O. Therefore, a significant number of patients require an endotracheal tube cuff pressure of ＞30 cmH2O to prevent air leakage. Several factors, including the surgical operation, intubation route, and difference between the cuff inner diameter and tracheal area at the T3 vertebra, should be considered when determining the appropriate cuff pressure during mechanical ventilation.

KMT2D regulates activation, localization, and integrin expression by T-cells.

Individuals with Kabuki syndrome present with immunodeficiency; however, how pathogenic variants in the gene encoding the histone-modifying enzyme lysine methyltransferase 2D (KMT2D) lead to immune alterations remain poorly understood. Following up on our prior report of KMT2D-altered integrin expression in B-cells, we performed targeted analyses of KMT2D's influence on integrin expression in T-cells throughout development (thymocytes through peripheral T-cells) in murine cells with constitutive- and conditional-targeted Kmt2d deletion. Using high-throughput RNA-sequencing and flow cytometry, we reveal decreased expression (both at the transcriptional and translational levels) of a cluster of leukocyte-specific integrins, which perturb aspects of T-cell activation, maturation, adhesion/localization, and effector function. H3K4me3 ChIP-PCR suggests that these evolutionary similar integrins are under direct control of KMT2D. KMT2D loss also alters multiple downstream programming/signaling pathways, including integrin-based localization, which can influence T-cell populations. We further demonstrated that KMT2D deficiency is associated with the accumulation of murine CD8+ single-positive (SP) thymocytes and shifts in both human and murine peripheral T-cell populations, including the reduction of the CD4+ recent thymic emigrant (RTE) population. Together, these data show that the targeted loss of Kmt2d in the T-cell lineage recapitulates several distinct features of Kabuki syndrome-associated immune deficiency and implicates epigenetic mechanisms in the regulation of integrin signaling.