Massilia luteola sp. nov., a novel indole-producing and cellulose-degrading bacterium isolated from soil.

A Gram-stain-negative, rod-shaped, indole-producing, and cellulose-degrading bacterial strain, designated NEAU-G-C5T, was isolated from soil collected from a forest in Dali city, Yunnan province, south China. 16S rRNA gene sequence analysis showed that strain NEAU-G-C5T was assigned to the genus Massilia and showed high sequence similarities to Massilia phosphatilytica 12-OD1T (98.32 %) and Massilia putida 6 NM-7T (98.41 %). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain NEAU-G-C5T formed a lineage related to M. phosphatilytica 12-OD1T and M. putida 6 NM-7T. The major fatty acids of the strain were C16 : 0, C16 : 1 ω7c, and C17 : 0 cyclo. The respiratory quinone was Q-8. The polar lipid profile of the strain showed the presence of diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine. In addition, the average nucleotide identity values between strain NEAU-G-C5T and its reference strains M. phosphatilytica 12-OD1T, M. putida 6 NM-7T, M. norwichensis NS9T, and M. kyonggiensis TSA1T were 89.7, 88.2, 81.3, and 88.0 %, respectively, and the levels of digital DNA-DNA hybridization between them were found to be 58.5 % (54.9-62.0 %), 53.2 % (49.8-56.7 %), 31.9 % (28.6-35.5 %), and 57.7 % (54.1-61.2 %), respectively, which were lower than the accepted threshold values of 95-96 % and 70 %, respectively. The DNA G+C content of strain NEAU-G-C5T was 66.5 mol%. The strain could produce indoleacetic acid and cellulase. On the basis of the phenotypic, genotypic, and chemotaxonomic characteristics, we conclude that strain NEAU-G-C5T represents a novel species of the genus Massilia, for which the name Massilia luteola sp. nov. is proposed. The type strain is NEAU-G-C5T (=MCCC 1K08668T=KCTC 8080T).

Risk factors and incidence of postoperative delirium after cardiac surgery in children: a systematic review and meta-analysis.

Delirium, a form of acute cerebral dysfunction, is a common complication of postoperative cardiac surgery in children. It is strongly associated with adverse outcomes, including prolonged hospitalization, increased mortality, and cognitive dysfunction. This study aimed to identify risk factors and incidence of delirium after cardiac surgery in children to facilitate early identification of delirium risk and provide a reference for the implementation of effective prevention and management. A systematic literature search was conducted in PubMed, Web of Science, Embase, Cochrane Library, Scopus, CNKI, Sinomed, and Wanfang for studies published in English or Chinese from the inception of each database to November 2023. The PRISMA guidelines were followed in all phases of this systematic review. The Risk of Bias Assessment for Nonrandomized Studies tool was used to assess methodological quality. A total of twelve studies were included in the analysis, with four studies classified as overall low risk of bias, seven studies as moderate risk of bias, and one study as high risk of bias. The studies reported 39 possible predictors of delirium, categorized into four broad groups: intrinsic and parent-related factors, disease-related factors, surgery and treatment-related factors, and clinical scores and laboratory parameters. By conducting qualitative synthesis and quantitative meta-analysis, we identified two definite factors, four possible factors, and 32 unclear factors related to delirium. Definite risk factors included age and mechanical ventilation duration. Possible factors included developmental delay, cyanotic heart disease, cardiopulmonary bypass time, and pain score. With only a few high-quality studies currently available, well-designed and more extensive prospective studies are still needed to investigate the risk factors affecting delirium and explore delirium prevention strategies in high-risk children.

Predictors of extubation failure in newborns: a systematic review and meta-analysis.

Extubation failure (EF) is a significant concern in mechanically ventilated newborns, and predicting its occurrence is an ongoing area of research. To investigate the predictors of EF in newborns undergoing planned extubation, we conducted a systematic review and meta-analysis. A systematic literature search was conducted in PubMed, Web of Science, Embase, and Cochrane Library for studies published in English from the inception of each database to March 2023. The PRISMA guidelines were followed in all phases of this systematic review. The Risk of Bias Assessment for Nonrandomized Studies tool was used to assess methodological quality. Thirty-four studies were included, 10 of which were overall low risk of bias, 15 of moderate risk of bias, and 9 of high risk of bias. The studies reported 43 possible predictors in six broad categories (intrinsic factors; maternal factors; diseases and adverse conditions of the newborn; treatment of the newborn; characteristics before and after extubation; and clinical scores and composite indicators). Through a qualitative synthesis of 43 predictors and a quantitative meta-analysis of 19 factors, we identified five definite factors, eight possible factors, and 22 unclear factors related to EF. Definite factors included gestational age, sepsis, pre-extubation pH, pre-extubation FiO2, and respiratory severity score. Possible factors included age at extubation, anemia, inotropic use, mean airway pressure, pre-extubation PCO2, mechanical ventilation duration, Apgar score, and spontaneous breathing trial. With only a few high-quality studies currently available, well-designed and more extensive prospective studies investigating the predictors affecting EF are still needed. In the future, it will be important to explore the possibility of combining multiple predictors or assessment tools to enhance the accuracy of predicting extubation outcomes in clinical practice.

Breastfeeding needs of mothers of preterm infants in China: a qualitative study informed by the behaviour change wheel.

BACKGROUND: Although breastfeeding is strongly recommended, the breastfeeding rate of preterm infants in China remains significantly low. In addition to the global structural challenges to breastfeeding and the physiological immaturity of preterm infants, Chinese mothers of preterm infants face unique challenges of maternal-infant separation after birth. Moreover, little is known about Chinese mothers' specific needs in coping with the difficulties posed by these challenges. This study utilized the Behaviour Change Wheel to investigate the breastfeeding needs of Chinese preterm mothers that may facilitate its practice in the future. METHOD: A qualitative descriptive design was implemented in Wuhan in 2022. Based on purposeful sampling, 13 preterm mothers were recruited from a NICU in a Grade III Class A hospital in Wuhan, China. Face-to-face semi-structured interviews were conducted to collect data using the interview guide developed by the Theoretical Domains Framework. Theoretical Thematic Analysis was used to review the data in 6 steps to identify themes. RESULTS: Five major themes emerged: (1) capability: ability to interpret infants' cues and identify problems, and need for breastfeeding knowledge and skills training; (2) physical opportunity: cleanliness and quietness in household environment, private lactation spaces and breastfeeding tools in workplaces and hospitals; (3) social opportunity: family support, peer support, and authoritative support from healthcare providers; (4) reflective motivation: information on health impacts of breastfeeding; (5) automatic motivation: maternal-infant bonding, free of aversive stimulus. CONCLUSION: Preterm mothers' needs to enable breastfeeding were diverse, including increasing their capability, physical and social opportunities, and reflective and automatic motivation. People, resources and environments associated with these needs should be engaged together to stablish a conducive structural environment for breastfeeding. The policy change for "zero separation" and implementation of kangaroo care should also be implemented in Chinese neonatal intensive care units. Future studies are needed to design effective interventions according to mothers' specific needs.

Risk factors for length of NICU stay of newborns: A systematic review.

Background: The improvement in survival of preterm infants is accompanied by an increase in neonatal intensive care unit (NICU) admissions. Prolonged length of stay in the NICU (LOS-NICU) increases the incidence of neonatal complications and even mortality and places a significant economic burden on families and strain on healthcare systems. This review aims to identify risk factors influencing LOS-NICU of newborns and to provide a basis for interventions to shorten LOS-NICU and avoid prolonged LOS-NICU. Methods: A systematic literature search was conducted in PubMed, Web of Science, Embase, and Cochrane library for studies that were published in English from January 1994 to October 2022. The PRISMA guidelines were followed in all phases of this systematic review. The Quality in Prognostic Studies (QUIPS) tool was used to assess methodological quality. Results: Twenty-three studies were included, 5 of which were of high quality and 18 of moderate quality, with no low-quality literature. The studies reported 58 possible risk factors in six broad categories (inherent factors; antenatal treatment and maternal factors; diseases and adverse conditions of the newborn; treatment of the newborn; clinical scores and laboratory indicators; organizational factors). Conclusions: We identified several of the most critical risk factors affecting LOS-NICU, including birth weight, gestational age, sepsis, necrotizing enterocolitis, bronchopulmonary dysplasia, and retinopathy of prematurity. As only a few high-quality studies are available at present, well-designed and more extensive prospective studies investigating the risk factors affecting LOS-NICU are still needed in the future.

A new ß-class milbemycin derivative from a mutant of genetically engineered strain Streptomyces avermitilis AVE-H39.

A new ß-class milbemycin, 13α-hydroxy milbemycin ß6 (1), was isolated from the fermentation broth of a mutant of genetically engineered strain Streptomyces avermitilis AVE-H39. Its structure and absolute configuration were elucidated by extensive spectroscopic methods and confirmed by single crystal X-ray diffraction.

Sarubicinols A-C, Cytotoxic Benzoxazoles from a Streptomyces.

A chemical investigation of Streptomyces sp. Hu186 afforded two known quinone antibiotics, sarubicin A (1) and sarubicin B (2), together with three unusual variants, sarubicinols A-C (3-5), and two new 1,4-naphthoquinone metabolites, sarubicin B1 (6) and sarubicin B2 (7). Compounds 3-5 possess a rare 2-oxabicyclo [2.2.2] substructure and a benzoxazole ring system. Their structures were elucidated using 1D and 2D nuclear magnetic resonance and high-resolution electrospray ionization mass spectrometry data. The absolute configurations of the side-chain moieties in 4 and 5 were solved by electronic circular dichroism calculations. Compounds 1-7 showed moderate cytotoxic activity against four tumor cell lines.

Two new cyclopentenone metabolites from Streptomyces sp. HU119.

Two previously undescribed cyclopentenone metabolites, (S)-2-(3-acetylamino-2-methyl)propyl-3-butyl-2-cyclopenten-1-one (1) and (S)-2-(3-acetylamino-2-ethyl)propyl-3-butyl-2-cyclopenten-1-one (2), were isolated from the fermentation broth of the strain Streptomyces sp. HU119. The structures of 1 and 2 were determined by the comprehensive spectroscopic analysis, including 1 D, 2 D NMR, MS spectral analysis and the comparison with data from the literature. The absolute configurations were elucidated by experimental and calculated optical rotations (OR). Compounds 1 and 2 displayed weak cytotoxic activity.

Description of a new strain of Streptomonospora nanhaiensis and reclassification of Streptomonospora halotolerans as a later heterotypic synonym of Streptomonospora nanhaiensis.

A novel actinomycete, designated strain NEAU-YY374, was isolated from root of wheat and a polyphasic taxonomic study was carried out. 16S rRNA gene sequence analysis indicated that strain NEAU-YY374 was closely related to Streptomonospora halotolerans NEAU-Jh2-17T (99.3 %) and Streptomonospora nanhaiensis 12A09T (98.6%). Phylogenetic analysis based on 16S rRNA gene sequences demonstrated that strain NEAU-YY374 formed a stable clade with S. halotolerans NEAU-Jh2-17T and S. nanhaiensis 12A09T in trees generated with two algorithms. Key morphological and chemotaxonomic properties also confirmed the affiliation of strain NEAU-YY374 to the genus Streptomonospora. The differences of DNA G+C contents among these three strains were all less than 1 %, and the digital DNA-DNA hybridization and the average nucleotide identity values were higher than the circumscription thresholds of species and subspecies, clearly indicating that the three strains should belong to the same species. Therefore, we concluded that strain NEAU-YY374 is a new strain of S. nanhaiensis. Meanwhile, S. halotolerans should be reclassified as a later heterotypic synonym of S. nanhaiensis according to the priority of publication and validation of the name.

Microbacterium stercoris sp. nov., an indole acetic acid-producing actinobacterium isolated from cow dung.

A novel growth-promoting and indole acetic acid-producing strain, designated NEAU-LLBT, was isolated from cow dung collected from Shangzhi, Heilongjiang Province, PR China. Cells of strain NEAU-LLBT were Gram-stain-positive, non-motile, aerobic and non-spore-forming. Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain NEAU-LLBT belonged to the genus Microbacterium. Strain NEAU-LLBT had high 16S rRNA sequence similarities of 98.81 and 98.41 % to Microbacterium paludicola DSM 16915T and Microbacterium marinilacus DSM 18904T, and less than 98 % to other members of the genus Microbacterium. Chemotaxonomic characteristics showed that MK-11 and MK-12 were detected as the predominant menaquinones. The peptidoglycan contained glutamic acid, aspartic acid, glycine, ornithine and a small amount of alanine, with ornithine as the diagnostic diamino acid. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol and an unidentified glycolipid. The major fatty acids were identified as anteiso-C15 : 0, iso-C16 : 0 and iso-C17 : 0. The genomic DNA G+C content of strain NEAU-LLBT was 70.2 mol%. In addition, the average nucleotide identity values between strain NEAU-LLBT and its reference strains, M. paludicola DSM 16915T, M. marinilacus DSM 18904T and M. album SYSU D8007T, were found to be 81.1, 79.4 and 78.7 %, respectively, and the level of digital DNA-DNA hybridization between them were 23.8, 22.6 and 21.8 %, respectively. Based on the phenotypic, phylogenetic and genotypic data, strain NEAU-LLBT is considered to represent a novel species of the genus Microbacterium, for which the name Microbacterium stercoris sp. nov is proposed, with NEAU-LLBT (=CCTCC AA 2018028T=JCM 32660T) as the type strain.

Taxonomic Characterization and Secondary Metabolite Analysis of NEAU-wh3-1: An Embleya Strain with Antitumor and Antibacterial Activity.

Cancer is a serious threat to human health. With the increasing resistance to known drugs, it is still urgent to find new drugs or pro-drugs with anti-tumor effects. Natural products produced by microorganisms have played an important role in the history of drug discovery, particularly in the anticancer and anti-infective areas. The plant rhizosphere ecosystem is a rich resource for the discovery of actinomycetes with potential applications in pharmaceutical science, especially Streptomyces. We screened Streptomyces-like strains from the rhizosphere soil of wheat (Triticum aestivum L.) in Hebei province, China, and thirty-nine strains were obtained. Among them, the extracts of 14 isolates inhibited the growth of colon tumor cell line HCT-116. Strain NEAU-wh-3-1 exhibited better inhibitory activity, and its active ingredients were further studied. Then, 16S rRNA gene sequence similarity studies showed that strain NEAU-wh3-1 with high sequence similarities to Embleya scabrispora DSM 41855T (99.65%), Embleya hyalina MB891-A1T (99.45%), and Streptomyces lasii 5H-CA11T (98.62%). Moreover, multilocus sequence analysis based on the five other house-keeping genes (atpD, gyrB, rpoB, recA, and trpB) and polyphasic taxonomic approach comprising chemotaxonomic, phylogenetic, morphological, and physiological characterization indicated that the isolate should be assigned to the genus Embleya and was different from its closely related strains, therefore, it is proposed that strain NEAU-wh3-1 may be classified as representatives of a novel species of the genus Embleya. Furthermore, active substances in the fermentation broth of strain NEAU-wh-3-1 were isolated by bioassay-guided analysis and identified by nuclear magnetic resonance (NMR) and mass spectrometry (MS) analyses. Consequently, one new Zincophorin analogue together with seven known compounds was detected. The new compound showed highest antitumor activity against three human cell lines with the 50% inhibition (IC50) values of 8.8-11.6 µg/mL and good antibacterial activity against four pathogenic bacteria, the other known compounds also exhibit certain biological activity.