Genomic and Metabolomic Analyses of Nocardiopsis maritima YSL2 as the Mycorrhizosphere Bacterium of Suaeda maritima (L.) Dumort.

Nine bacteria were isolated from the episphere of Suaeda maritima (L.) Dumort. Among them, the bacterial strain YSL2 displayed the highest antimicrobial activity on agar plates and exhibited significant novelty compared with other bacteria based on 16S rRNA analysis. Consequently, Nocardiopsis maritima YSL2T was subjected to phenotypic characterization and whole-genome sequencing. Phylogenetic analysis revealed its close association with Nocardiopsis aegyptia SNG49T. Furthermore, genomic analysis of strain YSL2T revealed the presence of various gene clusters, indicating its potential for producing antimicrobial secondary metabolites. Upon cultivation on a large scale, maritiamides A and B (1 and 2) were isolated and characterized as cyclic hexapeptides based on nuclear magnetic resonance, ultraviolet, infrared, and mass spectrometric data. The absolute configurations of the amino acid residues in the maritiamides were determined through chiral derivatization, utilizing FDAA and GITC. Maritiamides 1 and 2 exhibited promising antibacterial activities against Staphylococcus epidermidis and weakly inhibited the growth of Escherichia coli and Pseudomonas fluorescens.

Association between estimated glucose disposal rate and subclinical coronary atherosclerosis.

BACKGROUND AND AIMS: The estimated glucose disposal rate (eGDR) is an easily accessible clinical parameter for assessing insulin resistance in patients with diabetes mellitus. In this study, we aimed to investigate the link between eGDR and subclinical coronary atherosclerosis in an asymptomatic middle-aged Korean population. METHODS AND RESULTS: This study involved 4004 subjects who underwent routine health checkups with coronary multidetector computed tomography (MDCT) at Asan Medical Center from 2007 to 2011, among whom 913 had a follow-up analysis through 2014. The eGDR was calculated using: 21.16 - (0.09 ∗ waist circumference [cm]) - (3.41 ∗ hypertension) - (0.55 ∗ glycated hemoglobin [%]). Patients were categorized into three groups according to the tertiles of eGDR. Subclinical coronary atherosclerosis was defined by significant coronary stenosis (≥50%), presence of plaques, coronary artery calcification (CAC) score, and its progression. As a result, a lower eGDR level was associated with higher prevalence of significant coronary stenosis, plaques, moderate to severe CAC, and CAC progression. Compared to other markers or risk scores, eGDR was superior to other biomarkers of insulin resistance but did not provide additional information beyond classic cardiovascular risk models like the Framingham Risk Score and Pooled Cohort Equations. CONCLUSION: Decreased eGDR values were significantly associated with higher subclinical coronary atherosclerosis burdens in an asymptomatic middle-aged Korean population. However, its clinical implications remain uncertain due to its weaker performance compared to established cardiovascular risk models.

The structure of AcrIE4-F7 reveals a common strategy for dual CRISPR inhibition by targeting PAM recognition sites.

Bacteria and archaea use the CRISPR-Cas system to fend off invasions of bacteriophages and foreign plasmids. In response, bacteriophages encode anti-CRISPR (Acr) proteins that potently inhibit host Cas proteins to suppress CRISPR-mediated immunity. AcrIE4-F7, which was isolated from Pseudomonas citronellolis, is a fused form of AcrIE4 and AcrIF7 that inhibits both type I-E and type I-F CRISPR-Cas systems. Here, we determined the structure of AcrIE4-F7 and identified its Cas target proteins. The N-terminal AcrIE4 domain adopts a novel α-helical fold that targets the PAM interaction site of the type I-E Cas8e subunit. The C-terminal AcrIF7 domain exhibits an αß fold like native AcrIF7, which disables target DNA recognition by the PAM interaction site in the type I-F Cas8f subunit. The two Acr domains are connected by a flexible linker that allows prompt docking onto their cognate Cas8 targets. Conserved negative charges in each Acr domain are required for interaction with their Cas8 targets. Our results illustrate a common mechanism by which AcrIE4-F7 inhibits divergent CRISPR-Cas types.

Effect of positive end expiratory pressure on non-hypoxic apnea time and atelectasis during induction of anesthesia in infant: A randomized controlled trial.

INTRODUCTION: This study aimed to assess the impact of positive-end-expiratory pressure (PEEP) on the non-hypoxic apnea time in infants during anesthesia induction with an inspired oxygen fraction of 0.8. METHODS: This age stratified randomized controlled trial included patients under 1 year of age. Preoxygenation was performed using an inspired oxygen fraction of 0.8 for 2 min. Inspired oxygen fraction of 0.8 was administered via a face mask with volume-controlled ventilation at a tidal volume of 6 mL.kg-1, with or without 7 cmH2O of PEEP. Tracheal intubation was performed after 3 min of ventilation; however, it was disconnected from the breathing circuit. Ventilation was resumed once the pulse oximetry readings reached 95%. The primary outcome was the non-hypoxic apnea time, defined as the time from the cessation of ventilation to achieving a pulse oximeter reading of 95%. The secondary outcome measures included the degree of atelectasis assessed by ultrasonography and the presence of gastric air insufflation. RESULTS: Eighty-four patients were included in the final analysis. In the positive end-expiratory pressure group, the atelectasis score decreased (17.0 vs. 31.5, p < .001; mean difference and 95% CI of 11.6, 7.5-15.6), while the non-hypoxic apnea time increased (80.1 s vs. 70.6 s, p = .005; mean difference and 95% CI of -9.4, -16.0 to -2.9), compared to the zero end-expiratory pressure group, among infants who are 6 months old or younger, not in those aged older than 6 months. DISCUSSION: The application of positive end-expiratory pressure reduced the incidence of atelectasis and extended the non-hypoxic apnea time in infants who are 6 months old or younger. However, it did not affect the incidence of atelectasis nor the non-hypoxic apnea time in patients aged older than 6 months.

Determination of optimal positive end-expiratory pressure using electrical impedance tomography in infants under general anesthesia: Comparison between supine and prone positions.

AIMS: This study determined the optimal positive end-expiratory pressure levels in infants in supine and prone positions under general anesthesia using electrical impedance tomography (EIT). METHODS: This prospective observational single-centre study included infants scheduled for surgery in the prone position. An electrical impedance tomography sensor was applied after inducing general anesthesia. The optimal positive end-expiratory pressure in the supine position was determined in a decremental trial based on EIT and compliance. Subsequently, the patient's position was changed to prone. Electrical impedance tomography parameters, including global inhomogeneity index, regional ventilation delay, opening pressure, the centre of ventilation, and pendelluft volume, were continuously obtained up to 1 h after prone positioning. The optimal positive end-expiratory pressure in the prone position was similarly determined. RESULTS: Data from 30 infants were analyzed. The mean value of electrical impedance tomography-based optimal positive end-expiratory pressure in the prone position was significantly higher than that in the supine position [10.9 (1.6) cmH2O and 6.1 (0.9) cmH2O, respectively (p < .001)]. Significant differences were observed between electrical impedance tomography- and compliance-based optimal positive end-expiratory pressure. Peak and mean airway, plateau, and driving pressures increased 1 h after prone positioning compared with those in the supine position. In addition, the centre of ventilation for balance in ventilation between the ventral and dorsal regions improved. CONCLUSION: The prone position required higher positive end-expiratory pressure than the supine position in mechanically ventilated infants under general anesthesia. EIT is a promising tool to find the optimal positive end-expiratory pressure, which needs to be individualized.

Effect of high-flow nasal and buccal oxygenation on safe apnea time in children with open mouth: A randomized controlled trial.

BACKGROUND: High-flow nasal oxygenation is reported to prolong duration of apnea while maintaining adequate oxygen saturation with the mouth closed. Also, buccal oxygenation is known to have similar effects in obese adults. We compared the effect of these two methods on prolongation of acceptable apnea time in pediatric patients with their mouth open. METHODS: Thirty-eight patients, aged 0-10 years were randomly allocated to either the high-flow nasal oxygenation group (n = 17) or the buccal oxygenation group (n = 21). After induction of anesthesia including neuromuscular blockade, manual ventilation was initiated until the expiratory oxygen concentration reached 90%. Subsequently, ventilation was paused, and the patient's head was extended, and mouth was opened. The HFNO group received 2 L·min-1·kg-1 of oxygen, and the BO group received 0.5 L·min-1·kg-1 of oxygen. We set a target apnea time according to previous literature. When the apnea time reached the target, we defined the case as "success" in prolongation of safe apnea time and resumed ventilation. When the pulse oximetry decreased to 92% before the target apnea time, it was recorded as "failure" and rescue ventilation was given. RESULTS: The success rate of safe apnea prolongation was 100% in the high-flow nasal oxygenation group compared to 76% in the buccal oxygenation group (p = .04). Oxygen reserve index, end-tidal or transcutaneous carbon dioxide partial pressure, and pulse oximetry did not differ between groups. CONCLUSION: High-flow nasal oxygenation is effective in maintaining appropriate arterial oxygen saturation during apnea even in children with their mouth open and is superior to buccal oxygenation. Buccal oxygenation may be a good alternative when high-flow nasal oxygenation is not available.

Ultrasound-guided selective supraclavicular nerve block for postoperative pain control in children receiving Hickman catheter or chemoport insertion: A randomized controlled trial.

BACKGROUND: Optimal pain management after insertion of a central venous catheter in children remains unclear. AIM: This study aimed to evaluate the effects of a selective supraclavicular nerve block on postoperative analgesia in pediatric patients undergoing hickman catheter or chemoport insertion. METHODS: Fifty patients aged 3-18 years scheduled for elective Hickman or chemoport insertion were randomized into two groups of 25 each: one group received an ultrasound-guided selective supraclavicular nerve block with 0.1 mL/kg of 0.5% ropivacaine (SSCNB group), and the other group did not receive a nerve block (control group). The primary outcome was the postoperative Wong-Baker Faces Pain Rating Scale score measured between 10 and 30 min after surgery. Secondary outcomes included pain scores at 1, 3, and 24 h after the surgery, block-related complications, length of stay in the postanesthesia care unit, postoperative analgesic consumption, and time to first analgesic use 24 h after surgery. RESULTS: The worst pain score within 30 min in the recovery room was significantly lower in the SSCNB group compared to the control group (6 [5-7] vs. 3 [2-4]; median difference, -3; 95% CI, -4 to -1; p < .001). Pain scores at 1, 3, and 24 h after surgery were also significantly lower in the SSCNB group. The need for both opioid and non-opioid analgesics in the postoperative period was significantly lower in the SSCNB group (36.0% vs. 0%; p = .002 and 44.0% vs. 16.0%; mean difference, -28%; 95% CI, -56 to 0.19; p = .033, respectively), while other secondary outcomes were not significantly different between the two groups. CONCLUSIONS: Ultrasound-guided SSCNB is an effective method for managing postoperative pain in children undergoing Hickman catheter or chemoport insertion, reducing the need for analgesics within 24 h after surgery.

Oxygen reserve index versus conventional peripheral oxygen saturation for prevention of hypoxaemia: A randomised controlled trial.

BACKGROUND: Hypoxaemia occurs frequently during paediatric laryngeal microsurgery. OBJECTIVE: The oxygen reserve index is a noninvasive and continuous parameter to assess PaO2 levels in the range of 100 to 200 mmHg. It ranges from 0 to 1.0. We investigated whether monitoring the oxygen reserve index can reduce the incidence of SpO2 90% or less. DESIGN: Randomised controlled trial. SETTING: A tertiary care paediatric hospital. PARTICIPANTS: Paediatric patients aged 18 years or less scheduled to undergo laryngeal microsurgery. INTERVENTION: The patients were randomly allocated to the oxygen reserve index or control groups, and stratified based on the presence of a tracheostomy tube. Rescue intervention was performed when the oxygen reserve index was 0.2 or less and the SpO2 was 94% or less in the oxygen reserve index and control groups, respectively. MAIN OUTCOME MEASURE: The primary outcome was the incidence of SpO2 90% or less during the surgery. RESULTS: Data from 88 patients were analysed. The incidence of SpO2 ≤ 90% did not differ between the oxygen reserve index and control groups [P = 0.114; 11/44, 25% vs. 18/44, 40.9%; relative risk: 1.27; and 95% confidence interval (CI): 0.94 to 1.72]. Among the 128 rescue interventions, SpO2 ≤ 90% event developed in 18 out of 75 events (24%) and 42 out of 53 events (79.2%) in the oxygen reserve index and control groups, respectively (P < 0.001; difference: 55.2%; and 95% CI 38.5 to 67.2%). The number of SpO2 ≤ 90% events per patient in the oxygen reserve index group (median 0, maximum 3) was less than that in the control group (median 0, maximum 8, P = 0.031). CONCLUSION: Additional monitoring of the oxygen reserve index, with a target value of greater than 0.2 during paediatric airway surgery, alongside peripheral oxygen saturation, did not reduce the incidence of SpO2 ≤ 90%.

Effects of goal-directed analgesia using the analgesia nociception index in children undergoing surgery for moyamoya disease: A randomised controlled trial.

BACKGROUND: The potential benefits of Analgesia Nociception Index guided intra-operative analgesia on intra-operative opioid consumption remains to be demonstrated in paediatric anaesthesia. OBJECTIVES: This study aimed to explore the effects of Analgesia Nociception Index guided analgesia on sufentanil consumption during anaesthesia and postoperative pain scores in paediatric patients with moyamoya disease. DESIGN: A prospective randomised controlled study. SETTING: Seoul National University Children's Hospital, Seoul, Republic of Korea. PATIENTS: A total of 40 children scheduled for encephaloduroarteriosynangiosis. MAIN OUTCOME MEASURES: The primary outcome was total intra-operative sufentanil consumption, and the secondary outcomes included postoperative pain scores and incidence of opioid-related adverse events. RESULTS: The Analgesia Nociception Index group showed lower intra-operative sufentanil consumption (in µg kg -1  h -1 ) compared with the Standard group (0.30 ±â€Š0.12 and 0.39 ±â€Š0.17, respectively; mean difference, -0.09; 95% confidence interval, -0.19 to 0.00; P  = 0.049). Postoperatively, compared with the Standard group, the Analgesia Nociception Index group reported lower median pain scores at 18 and 24 h and maximum pain within 24 h (1 [0 to 2] vs. 3 [2 to 5]; P  = 0.004, 1 [0 to 2] vs. 3 [1 to 4]; P  = 0.041, and 4 [3 to 5] vs. 5 [4 to 7]; P  = 0.045, respectively), with fewer patients experiencing nausea (3 [15%] vs. 10 [50%], P  = 0.043). CONCLUSION: The Analgesia Nociception Index guided analgesic protocol can reduce intra-operative sufentanil consumption and postoperative pain within 24 h with fewer nausea symptoms in paediatric patients with moyamoya disease who undergo encephaloduroarteriosynangiosis. TRIAL REGISTRATION NUMBER: NCT05672212.

Atmospheric particulate matter and hypoxaemia in Korean children receiving general anaesthesia: A retrospective analysis.

BACKGROUND: The association between the concentration of atmospheric particulate matter on the day of surgery and the occurrence of intra-operative hypoxaemia in children receiving general anaesthesia is unclear. OBJECTIVE: To investigate the association between the exposure to particulate matter on the day of surgery and the occurrence of intra-operative hypoxaemia, defined as a pulse oximetry oxygen saturation of less than 90% for more than 1 min, in children. DESIGN: Retrospective study. SETTING: Single-centre. PARTICIPANTS: Children aged 18 years or younger who received general anaesthesia between January 2019 and October 2020. INTERVENTION: Information on daily levels of particulate matter with a diameter 10 µm or less and 2.5 µm or less measured within a neighbourhood corresponding to the area defined by the hospital's zip code was obtained from publicly available air-quality data. MAIN OUTCOME MEASURES: The primary outcome was intra-operative hypoxaemia, defined as a pulse oximetry oxygen saturation of less than 90% lasting for more than 1 min, manually verified by anaesthesiologists using vital sign registry data extracted at 2 s intervals. RESULTS: Of the patients finally analysed, 3.85% (489/13 175) experienced intra-operative hypoxaemia. Higher levels of particulate matter 10 µm or less in diameter (≥81 µg m -3 , 17/275, 6.2%) were associated with an increased occurrence of intra-operative hypoxaemia compared with lower particulate matter concentrations [<81 µg m -3 , 472/12 900, 3.7%; adjusted odds ratio, 1.71; 95% confidence interval (CI), 1.04 to 2.83; P  = 0.035]. CONCLUSION: The level of particulate matter on the day of surgery pose a risk of intra-operative hypoxaemia in children receiving general anaesthesia. If the concentrations of particulate matter 10 µm or less in diameter on the day of surgery are high, children receiving general anaesthesia should be managed with increased caution.