Oxygen Dependence Research Articles

Bronchopulmonary Dysplasia in Children. An Up-to-Date View of Disease Outcomes

Introduction. Bronchopulmonary dysplasia (BPD) is a chronic neonatal lung disease, with oxygen dependence by 36 weeks post conceptual age (PCA). Over the past decade, the frequency of the disease has increased. More and more modern scientific data are published that BPD has an adverse effect not just the development of the lungs, but also on the cardiovascular system. There is a large amount of information in the literature about the outcomes of BPD, but there is not enough information about the consequences of cardiovascular disorders in children with a history of BPD. Lack of clear criteria to predict and prevent to demonstrate cardiovascular disorders, were the basis for a detailed study of the literature concerning this issue.Purpose of the study based on study of the results of studies by local and foreign authors, to analyze the nature of cardiovascular disorders in children with a history of BPD, and to determine directions for more detailed scientific and practical search for a solution to this problem.Materials and methods. Research articles were searched for keywords “bronchopulmonary dysplasia” and “сardiovascular disorders” in the PubMed, UpToDate, Google Scholar databases, eLibrary.ru. At least 80 publications have been extracted from search results for simplification. Analyses of the results of studies by local and foreign authors on outcomes, BPD, including cardiovascular disorders, was carried out.Results and discussion. At the moment, the outcomes of BPD are well understood, while few information on cardiovascular disorders and possible prognosis for children who have undergone BPD.Conclusion. Cardiovascular disorders in children with a history of BPD are a pressing problem in pediatric practice. The presented literature review summarizes the information accumulated over several years on the outcomes of cardiovascular changes and determines the direction for further study of the problem, involving pediatricians and doctors of other specialties in order to identify groups at increased risk for the development of these diseases in children.

Effects of Chronic Obstructive Pulmonary Disease on the Outcomes of Fenestrated-Branched Endovascular Aortic Aneurysm Repair.

Chronic obstructive pulmonary disease (COPD) is common in patients with aortic aneurysms. Severe COPD is associated with an increased risk of aneurysm rupture and perioperative complications. This study assesses the outcomes of COPD and non-COPD patients after fenestrated-branched endovascular aortic aneurysm repair (FBEVAR). A single institution, retrospective study of FBEVAR patients between 2011 and 2020 compared outcomes between COPD and non-COPD patients. COPD patients were stratified by Global Initiative for Chronic Obstructive Lung Disease criteria and oxygen dependence. Outcome measures included 30-day mortality, pulmonary complications, major adverse events (MAE), and mid-term survival. 387 patients (71% male, age 72 years, interquartile range [68-79]) underwent FBEVAR. 181 patients (47%) had COPD. Smoking history was more frequent in COPD patients (P = .022). Among COPD patients, 20.4% were oxygen-dependent. Technical success, defined as successful delivery of the main aortic endograft and all intended side branches, was 98.4%. 30-day mortality (P = .83) and MAE rates (P = .87) were similar between groups. While not statistically significant, COPD patients had more frequent pulmonary complications (6.1% vs. 2.4%, P = .13) and were more frequently discharged on oxygen (P = .002). There were no differences in intensive care unit or hospital length of stay between groups (P = .29; P = .85, respectively). 5-year survival was similar between groups (P = .10). Oxygen-dependent COPD and severe-very severe COPD were associated with decreased mid-term survival (Hazard Ratio 2.39, P = .048). FBEVAR is safe and effective for treating complex aortic pathology in COPD patients, including oxygen-dependent patients. Patients with more severe COPD were more frequently discharged on oxygen. Mid-term survival was slightly reduced in patients with oxygen-dependent and severe-very severe COPD. Level 3, non-randomized controlled cohort/follow-up study.

Pulmonary outcomes of incretin-based therapies in COPD patients receiving single-inhaler triple therapy

IntroductionPatients with chronic obstructive pulmonary disease (COPD) on triple therapy often face exacerbations and comorbidities. Emerging evidence suggests that glucagon-like peptide-1 (GLP-1) analogs may reduce the risk of exacerbation in patients with COPD and type 2 diabetes mellitus (T2DM). This study investigates the impact of GLP-1 analogs on pulmonary outcomes in patients with COPD on single-inhaler triple therapy (SITT) and T2DM.MethodsWe conducted a retrospective cohort study using the TriNetX database and analysed adult patients with COPD and T2DM who received SITT between April 2005 and July 2023. Patients were categorized into GLP-1 analog and dipeptidyl peptidase-4 inhibitors (DPP4i) cohorts. The primary efficacy outcome was COPD exacerbation and the secondary efficacy outcomes were pneumonia, acute respiratory distress syndrome, intubation, oxygen dependence, and all-cause mortality. The secondary outcomes were serious gastrointestinal adverse events.ResultsWe included 6898 patients, with 4184 receiving GLP-1 analogs and 2714 receiving DPP4i. After matching, 1751 GLP-1 analog users were matched with 1751 DPP4i users. GLP-1 analog users had an 18% lower risk of COPD exacerbation (hazard ratio [HR], 0.82 [95% CI: 0.71–0.94]), a 28% reduced risk of pneumonia (HR, 0.72 [95% CI: 0.61–0.85]), a 34% reduced risk of oxygen dependence (HR, 0.66 [95% CI: 0.47–0.91]), and a 40% decreased risk of all-cause mortality (HR, 0.60 [95% CI: 0.47–0.77]). No significant serious gastrointestinal adverse events were observed.ConclusionGLP-1 analogs may be associated with reduced COPD exacerbations, pulmonary comorbidities, and mortality in patients with COPD receiving SITT and T2DM, with no significant serious gastrointestinal safety concerns.

Clinical outcomes of children with COVID-19 and appendicitis: a propensity score matched analysis.

Early in the COVID-19 pandemic, many children with appendicitis and COVID-19 were initially treated non-operatively and later underwent interval appendectomy. Currently, children with both appendicitis and COVID-19 frequently undergo upfront appendectomy. The impact of this return to upfront surgical management on patient outcomes is unknown. This study compared outcomes of pediatric patients with and without COVID-19 infection undergoing appendectomy. A retrospective cohort study of children < 21y who underwent appendectomy from 3/19/2020 to 7/31/2022 at 50 Pediatric Health Information System children's hospitals was conducted. Children with documented COVID-19 were identified. Exclusions included preoperative ventilator or supplemental oxygen dependence, and missing data. To evaluate COVID-19 positive versus COVID-19 negative patients, we used a propensity score matched on sociodemographics, comorbidities, laparoscopy, perforation, and hospital. Chi-square and Mann-Whitney U tests identified differences between groups in length of stay, postoperative drain placement, 30-day re-admission, and mechanical ventilation requirements. Overall, 51,861 children of median age 11y (IQR: 8-14) underwent appendectomy, of whom 1,440 (2.3%) had COVID-19. Most were male (60.3%), White (72.1%) and non-Hispanic (61.4%). Public insurance was the most common (47.5%). We created a matched cohort of 1,360 COVID-19 positive and 1,360 COVID-19 negative children. Children with COVID-19 had shorter hospitalizations (1d, IQR: 1-4 vs. 2d, IQR: 1-5, p = 0.03), less postoperative peritoneal drain placement (2.4% vs. 4.1%, p = 0.01), and fewer 30-day readmissions (9.0% vs. 11.4%, p = 0.04). However, no difference in incidence or duration of mechanical ventilation (p > 0.05) was detected. Our findings suggest that upfront appendectomy for children with appendicitis and COVID-19 has similar outcomes compared to children without COVID-19. Level III.

Why do patients stay in hospital after enhanced recovery thoracoscopic wedge resection? A prospective observational study.

This single-centre prospective observational study aimed to investigate reasons for prolonged hospitalization [over the median length of stay (LOS)] after enhanced recovery thoracoscopic [ERAS 3-port video-assisted thoracoscopic surgery (VATS)] wedge resection. All patients were evaluated twice-daily by an investigator for reasons of hospitalization. Each reason was analysed individually. Predictors for prolonged hospitalization were identified using a multivariable backward stepwise logistic regression model. A total of 150 consecutive patients (lymphadenectomy 8.7%) were included from November 2022 to December 2023, with a median LOS of 1 (interquartile range 1-2) day. Of these, 55 patients (36.7%) experienced prolonged hospitalization. The main reasons included postoperative pain (16.0%), air leak (14.7%) and social factors (14.7%), followed by oxygen dependency (7.3%), gastrointestinal factors (5.3%), urinary factors (4.7%), pneumonia (1.3%), pleural effusion (1.3%), chylothorax (0.7%), atrial fibrillation (0.7%), confusion (0.7%) and fatigue (0.7%). Multivariable analysis revealed that an increase in the percentage of predicted forced expiratory volume in 1 s (FEV1%pre) by 1% [odds ratio (OR) 0.41, P = 0.023) and percentage of predicted diffusing capacity for carbon monoxide (DLCO%pre) by 1% (OR 0.95, P = 0.002) decreased likelihood of prolonged hospitalization. Conversely, each additional pack-year (OR 1.01, P = 0.028) and living alone (OR 3.55, P = 0.005) increased the risk of prolonged hospitalization. Prolonged hospitalization (LOS > 1 day) after ERAS 3-port VATS wedge resection, with 8.7% lymphadenectomy, was mainly due to pain, air leak and social factors. Smokers with decreased FEV1%pre or DLCO%pre and patient living alone were at increased risk. ClinicalTrials.gov: NCT06118593 (https://clinicaltrials.gov/study/NCT06118593?cond=why%20in%20hospital&rank=2).

Ultra-Low-Power, Extremely Stable, Highly Linear-Response Thermal Conductivity Sensor Based on a Suspended Device with Single Bare Pt Nanowire.

The continuous and stable monitoring by sensors is crucial for ensuring the safe utilization of hydrogen due to its inherent high explosiveness. Currently, catalyst aging and oxygen dependence often limit the lifetime of most sensors, which stems from the sensing materials and catalytic reaction in comparison to thermal conductivity sensors. Thermal conductivity sensors possess superior sensing characteristics such as lowpower consumption and exceptional stability attributed to their free-catalysts or free-oxygen nature. Herein, we present an ultralow-power hydrogen-thermal conductivity sensor based on suspended bare platinum nanowires. This sensor incorporates two suspended independent working elements (serpentine/bridge), each of which is thermally decoupled from the substrate. Also, the bridge element operates at significantly lower power levels (the lowest ∼3.32 μW) compared to existing direct-current hydrogen-thermal conductivity sensors. Furthermore, it demonstrates a 99.99% linearity between hydrogen concentration and response under various operating powers. Finally, our sensor shows remarkable stability through a repeatability test (>30,000 cycles). This developed platform provides an optimal structure scheme for integrated sensors with ultralow-power, extremely stable, highly linear-response sensing characteristics, which is expected to be widely used for hydrogen detection and leakage warning under various pipeline distribution systems.

PEGylate engineering for preparing water-soluble deep/near-infrared red type I/II photosensitizer and its efficient photodynamic therapy of cancer cells

Photodynamic therapy has still received more research attention because of its significant advantages of minimally invasive, high selectivity and non-drug-resistance. Photosensitizer is one of important compositions in the photodynamic therapy process, which could be divided into two categories of containing energy transfer dominant process (type II) and electron transfer dominant process (type I) from triplet state to oxygen. Usually, type I photosensitizers have the merit of low oxygen dependence, leading them to become a popular and important candidate for treating cancers because there is hypoxic environment in the solid tumor. However, poor water solubility and short emissive wavelength of reported type I photosensitizer make them suffer certain limitation in clinical application. Hence, it is urgent to develop water-soluble near-infrared red type I photosensitizer. Herein, choosing classical biocompatible macromolecule of polyethylene glycol to modify the designed ionic type I photosensitizer with aggregation-induced near-infrared red fluorescence to prepare a new water-soluble polymeric type I/II photosensitizer (named as PEG-MTPABZ-PyC). PEG-MTPABZ-PyC displays remarkable water solubility (37 µg/mL), and maximal fluorescent wavelength peaks at 670 nm and extends to 850 nm of tail of fluorescent spectrum in aqueous solution, which endows it better efficiency of labelling cells by the significant red fluorescence. Additionally, its superior type I/II reactive oxygen species provide better killing of cancer cells in vitro. This study provides an effective method to prepare water-soluble near-infrared red type I/II photosensitizer, which exhibits satisfactory photophysical property and biocompatibility as well as excellent efficiency for killing cancer cells under normoxia and hypoxia, offering great potential for clinical disease treatment.

MULTI-SYSTEM INFLAMMATORY SYNDROME IN PATIENTS ADMITTED AT NICU OF A TERTIARY CARE HOSPITAL

Multi-inflammatory syndrome in neonates (MIS-N) associated with COVID-19 is an emerging concern in neonatal intensive care units (NICUs). Understanding its clinical spectrum and outcomes is crucial for developing management strategies and improving neonatal care. Objective: To explore the clinical spectrum, associated laboratory markers, and outcomes of neonates diagnosed with MIS-N and COVID-19 admitted to the NICU. Methods: This case series was conducted at the NICU of Shifa International Hospital, Islamabad, from January 2023 to June 2023. It included 47 infants diagnosed with COVID-19 who developed MIS-N. Data collected encompassed clinical presentations, laboratory markers, treatments administered in the ICU, and clinical outcomes. Descriptive statistics were used to analyze the data, focusing on symptoms, treatment efficacy, and complications. Results: The neonates had a mean age of 20.65 ± 16.60 days and a mean gestational age of 36.40 ± 2.62 weeks. Elevated inflammatory markers were noted, with D-Dimers elevated in 46.8%, serum ferritin in 66%, and C-reactive protein (CRP) in 48.9% of patients. The most common symptoms included respiratory distress (74.5%), poor feeding (38.3%), and fever (29.8%). Significant findings included pulmonary hypertension in 27.7% of the patients, patent ductus arteriosus in 23.4%, and other cardiovascular anomalies. Complications such as sepsis (70.2%), oxygen dependency (21.3%), and renal failure (29.8%) were prevalent. The mortality rate was 12.8%. Conclusion: MIS-N presents a severe threat to neonates with COVID-19, demonstrating high rates of serious complications and a notable mortality rate. Echocardiography is essential for early detection of cardiac dysfunctions. These findings underscore the urgent need for specific guidelines for the early recognition and management of MIS-N in neonates.

Clinicoepidemiological Profile of Retinopathy of Prematurity.

Purpose In previously performed studies, retinopathy of prematurity (ROP) has been shown to occur postpartum. As a result, mechanical ventilation and oxygen dependence were eventually connected to the development of ROP in these preterm children, and ROP prevalence is on the rise globally. Despite various improvements in childcare, ROP still tends to arise due to various risk factors associated with the disease. So, clinically the research was performed to determine the clinical and epidemiological profile of ROP. Materials and methods A total of 268 participants were to be enrolled in the study. It was an observational, cross-sectional study carried out at Department of Ophthalmology and Neonatal Intensive Care Unit in Veer Surendra Sai Institute of Medical Sciences and Research Centre, Burla, Sambalpur, Odisha, India. Ethical approval was provided on 30 November 2019. Results Overall 123 (46%) infants out of 268 infants developed retinopathy of prematurity. Majorly, the infants had stage 1 and stage 2 ROP. Most of the infants were male. Birth weight in ROP patients was 1000 g or less in 54% of infants, 1000-1500 g in 46% of infants and >1500 g in 33% of infants. Gestational age was found to be a predictor of retinopathy of prematurity. The adverse events that were found to be associated with retinopathy of prematurity were sepsis (53%), respiratory distress syndrome (RDS) (54.6%), intraventricular haemorrhage (IVH) (60%), anaemia (61.5%). Conclusion It has been observed that babies with higher birth weights and older gestations are also susceptible to developing ROP. Therefore, the greater birth weight newborns up to 1750 g and older gestational age babies >34 weeks should also be included in the screening criteria, especially if they have risk factors such as oxygen supplementation, sepsis, RDS, and anaemia.

Postoperative pulmonary complications in patients with chronic obstructive pulmonary disease undergoing primary laparoscopic bariatric surgery: an MBSAQIP analysis

BackgroundRecent research has shown beneficial effects of bariatric surgery (BaS) on the risk of developing acute exacerbations of chronic obstructive pulmonary disease (COPD). However, this patient population may be at increased risk of complications, especially postoperative pulmonary complications (PPC). ObjectivesTo analyze the incidence of PPC in patients with COPD undergoing BaS. SettingAcademic Hospital, United States. MethodsWe performed a retrospective analysis of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database for patients aged ≥18 years undergoing laparoscopic sleeve gastrectomy and Roux-en-Y gastric bypass during 2015–2019. The primary outcome of the study was any PPC, defined as a composite variable including postoperative pneumonia, mechanical ventilation >48 hours and unplanned endotracheal intubation. A univariate analysis was performed to compare patients with and without COPD, and a multivariate logistic regression was performed to adjust for confounders. A subgroup analysis was performed to compare endpoints in patients with COPD with or without home oxygen requirements. ResultsA total of 752,722 patients were included in our analysis (laparoscopic sleeve gastrectomy = 73.2%, Roux-en-Y gastric bypass = 26.8%). PPC occurred in 2390 patients, 0.3% without COPD versus 1.3% with COPD (P < .001). Multivariable analysis confirmed that COPD independently increases the risk of PPC (OR = 1.7, CI = 1.4–2.1). Subgroup analysis showed that patients who are oxygen dependent had a much higher risk for PPC (2.4% versus 1.1%, P < .001). ConclusionPPC are higher among patients with obesity and concomitant COPD. Oxygen dependency confers an even higher complication rate. The risk and benefits of BaS in this population must be carefully addressed.

Comparative proteomic analysis of metronidazole-sensitive and resistant Trichomonas vaginalis suggests a novel mode of metronidazole action and resistance

The microaerophilic parasite Trichomonas vaginalis occurs worldwide and causes inflammation of the urogenital tract, especially in women. With 156 million infections annually, trichomoniasis is the most prevalent non-viral sexually transmitted disease. Trichomoniasis is treated with 5-nitroimidazoles, especially metronidazole, which are prodrugs that have to be reduced at their nitro group to be activated. Resistance rates to metronidazole have remained comparably low, but they can be higher in certain areas leading to an increase of refractory cases. Metronidazole resistance in T. vaginalis can develop in vivo in clinical isolates, or it can be induced in the laboratory. Both types of resistance share certain characteristics but differ with regard to the dependence of ambient oxygen to become manifest. Although several candidate factors for metronidazole resistance have been described in the past, e.g. pyruvate:ferredoxin oxidoreductase and ferredoxin or thioredoxin reductase, open questions regarding their role in resistance have remained.In order to address these questions, we performed a proteomic study with metronidazole-sensitive and –resistant laboratory strains, as well as with clinical strains, in order to identify factors causative for resistance. The list of proteins consistently associated with resistance was surprisingly short. Resistant laboratory and clinical strains only shared the downregulation of flavin reductase 1 (FR1), an enzyme previously identified to be involved in resistance. Originally, FR1 was believed to be an oxygen scavenging enzyme, but here we identified it as a ferric iron reductase which produces ferrous iron. Based on this finding and on further experimental evidence as presented herein, we propose a novel mechanism of metronidazole activation which is based on ferrous iron binding to proteins, thereby rendering them susceptible to complex formation with metronidazole. Upon resolution of iron-protein-metronidazole complexes, metronidazole radicals are formed which quickly react with thiols or proteins in the direct vicinity, leading to breaks in the peptide backbone.

Comparison of supraglottic airway device and endotracheal tube in former preterm infants receiving general anesthesia: a randomized controlled trial

To date, endotracheal tube (ETT) remains the mainstream for preterm infants receiving general anesthesia. We aim to compare the perioperative respiratory adverse events between using supraglottic airway device (SAD) and ETT in former preterm infants receiving general anesthesia. Former preterm infants below 52 weeks of postmenstrual age scheduled for herniorrhaphy were randomized to receive SAD or ETT for general anesthesia. Infants with severe congenital cardiopulmonary disease, prolonged oxygen or mechanical ventilation dependence, and recent respiratory tract infection were excluded. Muscle relaxant agents and opioids were avoided in this study. 40 infants were assigned into SAD or ETT groups. Infants in the SAD group had a much lower rate of intraoperative desaturation than those in the ETT group (21.1% vs. 73.7%, p = 0.003). Incidences of other intraoperative and postoperative 24-h respiratory adverse events were similar between groups, including laryngospasm/bronchospasm, cough and stridor during anesthesia, and postoperative apnea, bradycardia, and supplemental oxygen use. All participants were extubated successfully in the operation room. SAD is recommended in former preterm infants receiving general anesthesia for herniorrhaphy in their early infancy as it much decreases the incidence of intraoperative desaturation compared to ETT.

Computed Tomography Spectrum of Complications in Usual Interstitial Pneumonia Pattern in a Tertiary Care Hospital: A Descriptive Cross- sectional Study.

Idiopathic pulmonary fibrosis is the most prevalent form of interstitial lung disease, which presents as usual interstitial pneumonia on histopathology and imaging. It leads to significant lung scarring, damage, and fibrosis and is associated with a high degree of mortality, repeated hospital admissions, and oxygen dependence. Many complications are associated with idiopathic pulmonary fibrosis, which further increases the morbidity of patients. High-resolution computed tomography chest is the imaging modality of choice for usual interstitial pneumonia tracking its progression, evaluating treatment response, and detecting potential complications. This descriptive cross-sectional study was approved by the Institutional Ethics Committee (Reference number: IEC-INT/2023/Study-1256). Departmental computed tomography report database from November, 2017 to June, 2018 was reviewed and scans with imaging features consistent with the 'usual interstitial pneumonia' pattern were identified. Total sampling method was used and two independent radiologists, blinded to the patient's clinical information, reviewed the high-resolution computed tomography chest scans to assess for imaging features of usual interstitial pneumonia and associated complications. Data was collected and analyzed using Microsoft Excel. There were 65 patients reported as unusual interstitial pneumonia pattern. Emphysema and pneumothorax were identified in 4 (6.15%) and 1 (1.53%) scans, respectively. Two (3.08%) scans showed features of pulmonary arterial hypertension. Ten (15.38%) scans exhibited findings consistent with co-existent or superimposed pulmonary infection. Additionally, features of lung malignancy were identified in high-resolution computed tomography scans of 5 (7.69%) patients. Patients with UIP often experience severe lung scarring, and frequent complications, and require regular chest CT scans to monitor disease progression and identify potential complications.

Sulfur-Vacancy-Engineered Two-Dimensional Cu@SnS2-x Nanosheets Constructed via Heterovalent Substitution for High-Efficiency Piezocatalytic Tumor Therapy.

Ultrasound (US)-mediated piezocatalytic tumor therapy has attracted much attention due to its notable tissue-penetration capabilities, noninvasiveness, and low oxygen dependency. Nevertheless, the efficiency of piezocatalytic therapy is limited due to an inadequate piezoelectric response, low separation of electron-hole (e--h+) pairs, and complex tumor microenvironment (TME). Herein, an ultrathin two-dimensional (2D) sulfur-vacancy-engineered (Sv-engineered) Cu@SnS2-x nanosheet (NS) with an enhanced piezoelectric effect was constructed via the heterovalent substitution strategy of Sn4+ by Cu2+. The introduction of Cu2+ ion not only causes changes in the crystal structure to increase polarization but also generates rich Sv to decrease band gap from 2.16 to 1.62 eV and inhibit e--h+ pairs recombination, collectively leading to the highly efficient generation of reactive oxygen species under US irradiation. Moreover, Cu@SnS2-x shows US-enhanced TME-responsive Fenton-like catalytic activity and glutathione depletion ability, further aggravating the oxidative stress. Both in vitro and in vivo results prove that the Sv-engineered Cu@SnS2-x NSs can significantly kill tumor cells and achieve high-efficiency piezocatalytic tumor therapy in a biocompatible manner. Overall, this study provides a new avenue for sonocatalytic therapy and broadens the application of 2D piezoelectric materials.

Isotopomer labeling and oxygen dependence of hybrid nitrous oxide production

Abstract. Nitrous oxide (N2O) is a potent greenhouse gas and ozone depletion agent, with a significant natural source from marine oxygen-deficient zones (ODZs). Open questions remain, however, about the microbial processes responsible for this N2O production, especially hybrid N2O production when ammonia-oxidizing archaea are present. Using 15N-labeled tracer incubations, we measured the rates of N2O production from ammonium (NH4+), nitrite (NO2-), and nitrate (NO3-) in the eastern tropical North Pacific ODZ and the isotopic labeling of the central (α) and terminal (β) nitrogen (N) atoms of the N2O molecule. We observed production of both doubly and singly labeled N2O from each tracer, with the highest rates of labeled N2O production at the same depths as the near-surface N2O concentration maximum. At most stations and depths, the production of 45N2Oα and 45N2Oβ were statistically indistinguishable, but at a few depths there were significant differences in the labeling of the two nitrogen atoms in the N2O molecule. Implementing the rates of labeled N2O production in a time-dependent numerical model, we found that N2O production from NO3- dominated at most stations and depths, with rates as high as 1600 ± 200 pM N2O d−1. Hybrid N2O production, one of the mechanisms by which ammonia-oxidizing archaea produce N2O, had rates as high as 230 ± 80 pM N2O d−1 that peaked in both the near-surface and deep N2O concentration maxima. Based on the equal production of 45N2Oα and 45N2Oβ in the majority of our experiments, we infer that hybrid N2O production likely has a consistent site preference, despite drawing from two distinct substrate pools. We also found that the rates and yields of hybrid N2O production were enhanced at low dissolved oxygen concentrations ([O2]), with hybrid N2O yields as high as 20 % at depths where [O2] was below detection (880 nM) but nitrification was still active. Finally, we identified a few incubations with [O2] up to 20 µM where N2O production from NO3- was still active. A relatively high O2 tolerance for N2O production via denitrification has implications for the feedbacks between marine deoxygenation and greenhouse gas cycling.

The Characteristics and Two-Year Neurodevelopmental Outcomes of Home Oxygen Therapy among Preterm Infants with Bronchopulmonary Dysplasia: A Retrospective Study in a Medical Center in Taiwan.

Home oxygen therapy (HOT) is frequently used as a therapeutic strategy for children experiencing chronic oxygen dependency associated with bronchopulmonary dysplasia (BPD). Recent studies have highlighted substantial variations in the characteristics and outcomes of infants requiring oxygen, primarily due to the absence of a consensus on the management of HOT in infants with BPD. We conducted this retrospective study and reviewed the medical records of extremely and very preterm infants who were diagnosed with BPD in a tertiary center in northern Taiwan from January 2020 to September 2021. Their neurodevelopmental outcomes were evaluated at 18 to 24 months of corrected age. A total of 134 patients diagnosed with BPD were divided into a HOT group (n = 39) and a room air group (n = 95). The children in the HOT group had a higher incidence of hemodynamic significant patent ductus arteriosus (PDA) (p = 0.005) and PDA ligation (p = 0.004), high-frequency oscillatory ventilation (p < 0.001), nitrogen oxide inhalation (p < 0.001), pulmonary hypertension (p = 0.01), and longer invasive ventilation (p < 0.001), as well as longer hospitalization (p < 0.001). A multivariate logistic regression model demonstrated that prolonged invasive ventilation (OR = 1.032, 95% CI 0.984-1.020, p = 0.001) was correlated with oxygen dependency in children. Infants with BPD born at advanced gestational age (OR = 0.760, 95%CI 0.582-0.992, p = 0.044) had a decreasing risk of requiring HOT. The children in the HOT group had a higher incidence of emergency room visits (p < 0.001) and re-hospitalization (p = 0.007) within one year of corrected age. The neurodevelopmental outcomes revealed the HOT group had an increasing portion of moderate to severe cognitive delay (18.2% vs. 3.7%, p = 0.009) and moderate to severe language delay (24.2% vs. 6.1%, p = 0.006) at 18 to 24 months of corrected age. In conclusion, infants with BPD necessitating HOT required prolonged invasive ventilation during hospitalization and exhibited a greater prevalence of unfavorable neurodevelopmental outcomes at 18 to 24 months of corrected age as well.

A Highly Charged Positive Cage Causes Simultaneous Enhancement of Type‐II and O2‐Independent‐Type‐I Photodynamic Therapy via One‐/Two‐Photon Stimulation and Tumor Immunotherapy via PANoptosis and Ferroptosis

To solve the oxygen dependence problem of photodynamic therapy (PDT), it is critical to explore photosensitizers that do not rely on O2 molecule to generate reactive oxygen species (ROS). Herein, a stable cationic metal‐organic cage [Pd6(RuLoz3)8](BF4)28 (MOC‐88) that possesses high +28 charges is designed. The cage‐confined positive microenvironment enables efficient generation of hydroxyl radicals and improved yield of the singlet oxygen under one‐/two‐photon excitation, showing excellent performance to concurrently enhance Type‐II and O2‐independent‐Type‐I PDT. Moreover, the effective ROS production and robust lipid peroxidation trigger a series of signaling pathways (inflammasome, cyclic guanosine monophosphate–adenosine monophosphate synthase stimulator of interferon genes, and NF‐κB) to evoke PANoptosis and ferroptosis in tumor cells, enabling MOC‐88 to simultaneously cause the loss of cell membrane integrity, release a series of inflammatory cytokines and damage‐associated molecular patterns, stimulate the maturation and antigen presentation ability of dendritic cells, and ultimately activate T‐cell‐dependent adaptive immunity in vivo to inhibit tumor growth.

Risk factors for chloral hydrate sedation failure in pediatric patients: a retrospective analysis.

This study aimed to investigate the risk factors for chloral hydrate sedation failure and complications in a tertiary children's hospital in South Korea. A retrospective analysis of pediatric procedural sedation with chloral hydrate between January 1, 2021, and March 30, 2022, was performed. The collected data included patient characteristics, sedation history, and procedure. Multivariable regression analysis was performed to identify the risk factors for procedural sedation failure and complications. A total of 6,691 procedural sedation were included in the analysis; sedation failure following chloral hydrate (50 mg/kg) occurred in 1,457 patients (21.8%) and was associated with a higher rate of overall complications compared to those with successful sedation (17.5% [225/1457] vs. 6.2% [322/5234]; P < 0.001, odds ratio: 3.236). In the multivariable regression analysis, the following factors were associated with increased risk of sedation failure: general ward or intensive care unit inpatient (compared with outpatient); congenital syndrome; oxygen dependency; history of sedation failure or complications with chloral hydrate; procedure more than 60 min; and magnetic resonance imaging, radiotherapy, or procedures with painful or intense stimuli (all P values < 0.05). Factors contributing to the complications included general ward inpatient, congenital syndromes, congenital heart disease, preterm birth, oxygen dependency, history of complications with chloral hydrate, and current sedation failure with chloral hydrate (all P values < 0.05). To achieve successful sedation with chloral hydrate, the patient's sedation history, risk factors, and the type and duration of the procedure should be considered.

Outcomes of surgical treatment of tracheobronchomalacia in children.

Tracheobronchomalacia (TBM) is characterized by excessive dynamic airway collapse. Severe TBM can be associated with substantial morbidity. Children with secondary TBM associated with esophageal atresia/tracheoesophageal fistula (EA/TEF) and vascular-related airway compression (VRAC) demonstrate clinical improvement following airway pexy surgery. It is unclear if children with severe primary TBM, without secondary etiologies (EA/TEF, vascular ring, intrinsic pulmonary pathology, or complex cardiac disease) demonstrate clinical improvement following airway pexy surgery. The study cohort consisted of 73 children with severe primary TBM who underwent airway pexy surgery between 2013 and 2020 at Boston Children's Hospital. Pre- and postoperative symptomsas well as bronchoscopic findings were compared with Fisher exact test for categorical data and Student'st-test for continuous data. Statistically significant improvements in clinical symptoms were observed, including cough, noisy breathing, prolonged respiratory infections, pneumonias, exercise intolerance, cyanotic spells, brief resolved unexplained events (BRUE), and noninvasive positive pressure ventilation (NIPPV) dependence. No significant differences were seen regarding oxygen dependence, ventilator dependence, or respiratory distress requiring NIPPV. Comparison of pre- and postoperative dynamic bronchoscopy findings revealed statistically significant improvement in the percent of airway collapse in all anatomic locations except at the level of the upper trachea (usually not malacic). Despite some initial improvements, 21 (29%) patients remained symptomatic and underwent additional airway pexies with improvement in symptoms. Airway pexy surgery resulted in significant improvement in clinical symptoms and bronchoscopic findings for children with severe primary TBM; however, future prospective and long-term studies are needed to confirm this benefit.

Molecular engineering design of twisted-backbone pure Type-I organic photosensitizers for hypoxic photodynamic therapy

Photodynamic therapy (PDT), an emerging tumor therapeutic strategy has received tremendous attention. Enslaved by the high dependence of oxygen, Type-II photosensitizers (PSs) mediated PDT is restricted by the hypoxic environment of tumors. By transferring electrons to water or other substrates instead of oxygen, Type-I PSs hold the promise of achieving an ideal therapeutic effect under hypoxic conditions. In this study, three twisted-backbone PSs (CBz-TQs-1, CBz-TQs-2 and CBz-TQs-3) are synthesized and studied. Owing to different substituent effects, the ROS generation mechanism transfers from pure Type-II of their prototype PSs (TQs-1, TQs-2 and TQs-3) to mixed Type-I/II of CBz-TQs-1 and CBz-TQs-2 to pure Type-I of CBz-TQs-3. Moreover, CBz-TQs-3 exhibits an ultra-high ROS quantum yield (∼1.0). The in vitro and in vivo PDT effects of water-dissolvable nanoparticles (NPs) of CBz-TQs-3 are investigated. The results show that the phototoxicity of CBz-TQs-3 is not affected by hypoxic environments. In addition, a remarkable tumor ablation can be found after CBz-TQs-3 NPs mediated PDT on Balb/c mice with xenograft tumors. It proves that a twisted backbone strategy is beneficial for designing pure Type-I PSs with high-efficient hypoxic PDT.