The gut microbiota-bile acid axis in cholestatic liver disease.

Cholestatic liver diseases (CLD) are characterized by impaired normal bile flow, culminating in excessive accumulation of toxic bile acids. The majority of patients with CLD ultimately progress to liver cirrhosis and hepatic failure, necessitating liver transplantation due to the lack of effective treatment. Recent investigations have underscored the pivotal role of the gut microbiota-bile acid axis in the progression of hepatic fibrosis via various pathways. The obstruction of bile drainage can induce gut microbiota dysbiosis and disrupt the intestinal mucosal barrier, leading to bacteria translocation. The microbial translocation activates the immune response and promotes liver fibrosis progression. The identification of therapeutic targets for modulating the gut microbiota-bile acid axis represents a promising strategy to ameliorate or perhaps reverse liver fibrosis in CLD. This review focuses on the mechanisms in the gut microbiota-bile acids axis in CLD and highlights potential therapeutic targets, aiming to lay a foundation for innovative treatment approaches.

Development of a diagnostic model for biliary atresia based on MMP7 and serological tests using machine learning.

OBJECTIVE: To develop a machine learning diagnostic model based on MMP7 and other serological testing indicators for early and efficient diagnosis of biliary atresia (BA). METHODS: A retrospective analysis was conducted on patient information from those hospitalized for pathological jaundice at Beijing Children's Hospital between January 1, 2019, and December 31, 2023. Patients with serum MMP7, liver stiffness measurements, and other routine serological tests were included in the study. Six machine learning models were constructed, including logistic regression (LR), random forest (RF), decision tree (DET), support vector machine classifier (SVC), neural network (MLP), and extreme gradient boosting (XGBoost), to diagnose BA. The area under the receiver operating characteristic curve was used to evaluate the diagnostic efficacy of the various models. RESULTS: A total of 98 patients were included in the study, comprising 64 BA patients and 34 patients with other cholestatic liver diseases. Among the six machine learning models, the XGBoost algorithm model and RF algorithm model achieved the best predictive performance, with an AUROC of nearly 100% in both the training and validation sets. In the training set, these two algorithm models achieved an accuracy, precision, recall, F1 score, and AUROC of 1. Through model interpretation analysis, serum MMP7 levels, serum GGT levels, and acholic stools were identified as the most important indicators for diagnosing BA. The nomogram constructed based on the XGBoost algorithm model also demonstrated convenient and efficient diagnostic efficacy. CONCLUSION: Machine learning models, especially the XGBoost algorithm and RF algorithm models, constructed based on preoperative serum MMP7 and serological tests can diagnose BA more efficiently and accurately. The most important influencing factors for diagnosis are serum MMP7, serum GGT, and acholic stools.

Redundant and scattered genetic determinants for coumarin biodegradation in Pseudomonas sp. strain NyZ480.

Coumarin (COU) is both a naturally derived phytotoxin and a synthetic pollutant which causes hepatotoxicity in susceptible humans. Microbes have potentials in COU biodegradation; however, its underlying genetic determinants remain unknown. Pseudomonas sp. strain NyZ480, a robust COU degrader, has been isolated and proven to grow on COU as its sole carbon source. In this study, five homologs of xenobiotic reductase A scattered throughout the chromosome of strain NyZ480 were identified, which catalyzed the conversion of COU to dihydrocoumarin (DHC) in vitro. Phylogenetic analysis indicated that these COU reductases belong to different subgroups of the old yellow enzyme family. Moreover, two hydrolases (CouB1 and CouB2) homologous to the 3,4-dihydrocoumarin hydrolase in the fluorene degradation were found to accelerate the generation of melilotic acid (MA) from DHC. CouC, a new member from the group A flavin monooxygenase, was heterologously expressed and purified, catalyzing the hydroxylation of MA to produce 3-(2,3-dihydroxyphenyl)propionate (DHPP). Gene deletion and complementation of couC indicated that couC played an essential role in the COU catabolism in strain NyZ480, considering that the genes involved in the downstream catabolism of DHPP have been characterized (Y. Xu and N. Y. Zhou, Appl Environ Microbiol 86:e02385-19, 2020) and homologous catabolic cluster exists in strain NyZ480. This study elucidated the genetic determinants for complete degradation of COU by Pseudomonas sp. strain NyZ480.IMPORTANCECoumarin (COU) is a phytochemical widely distributed in the plant kingdom and also artificially produced as an ingredient for personal care products. Hence, the environmental occurrence of COU has been reported in different places. Toxicologically, COU was proven hepatotoxic to individuals with mutations in the CYP2A6 gene and listed as a group 3 carcinogen by the International Agency for Research on Cancer and thus has raised increasing concerns. Until now, different physicochemical methods have been developed for the removal of COU, whereas their practical applications were hampered due to high cost and the risk of secondary contamination. In this study, genetic evidence and biochemical characterization of the COU degradation by Pseudomonas sp. strain NyZ480 are presented. With the gene and strain resources provided here, better managements of the hazards that humans face from COU could be achieved, and the possible microbiota-plant interaction mediated by the COU-utilizing rhizobacteria could also be investigated.

Microbial Diversity Biased Estimation Caused by Intragenomic Heterogeneity and Interspecific Conservation of 16S rRNA Genes.

The 16S rRNA gene has been extensively used as a molecular marker to explore evolutionary relationships and profile microbial composition throughout various environments. Despite its convenience and prevalence, limitations are inevitable. Variable copy numbers, intragenomic heterogeneity, and low taxonomic resolution have caused biases in estimating microbial diversity. Here, analysis of 24,248 complete prokaryotic genomes indicated that the 16S rRNA gene copy number ranged from 1 to 37 in bacteria and 1 to 5 in archaea, and intragenomic heterogeneity was observed in 60% of prokaryotic genomes, most of which were below 1%. The overestimation of microbial diversity caused by intragenomic variation and the underestimation introduced by interspecific conservation were calculated when using full-length or partial 16S rRNA genes. Results showed that, at the 100% threshold, microbial diversity could be overestimated by as much as 156.5% when using the full-length gene. The V4 to V5 region-based analyses introduced the lowest overestimation rate (4.4%) but exhibited slightly lower species resolution than other variable regions under the 97% threshold. For different variable regions, appropriate thresholds rather than the canonical value 97% were proposed for minimizing the risk of splitting a single genome into multiple clusters and lumping together different species into the same cluster. This study has not only updated the 16S rRNA gene copy number and intragenomic variation information for the currently available prokaryotic genomes, but also elucidated the biases in estimating prokaryotic diversity with quantitative data, providing references for choosing amplified regions and clustering thresholds in microbial community surveys. IMPORTANCE Microbial diversity is typically analyzed using marker gene-based methods, of which 16S rRNA gene sequencing is the most widely used approach. However, obtaining an accurate estimation of microbial diversity remains a challenge, due to the intragenomic variation and low taxonomic resolution of 16S rRNA genes. Comprehensive examination of the bias in estimating such prokaryotic diversity using 16S rRNA genes within ever-increasing prokaryotic genomes highlights the importance of the choice of sequencing regions and clustering thresholds based on the specific research objectives.

Solving Graph Problems Using Gaussian Boson Sampling.

Gaussian boson sampling (GBS) is not only a feasible protocol for demonstrating quantum computational advantage, but also mathematically associated with certain graph-related and quantum chemistry problems. In particular, it is proposed that the generated samples from the GBS could be harnessed to enhance the classical stochastic algorithms in searching some graph features. Here, we use Jiǔzhang, a noisy intermediate-scale quantum computer, to solve graph problems. The samples are generated from a 144-mode fully connected photonic processor, with photon click up to 80 in the quantum computational advantage regime. We investigate the open question of whether the GBS enhancement over the classical stochastic algorithms persists-and how it scales-with an increasing system size on noisy quantum devices in the computationally interesting regime. We experimentally observe the presence of GBS enhancement with a large photon-click number and a robustness of the enhancement under certain noise. Our work is a step toward testing real-world problems using the existing noisy intermediate-scale quantum computers and hopes to stimulate the development of more efficient classical and quantum-inspired algorithms.

Gaussian Boson Sampling with Pseudo-Photon-Number-Resolving Detectors and Quantum Computational Advantage.

We report new Gaussian boson sampling experiments with pseudo-photon-number-resolving detection, which register up to 255 photon-click events. We consider partial photon distinguishability and develop a more complete model for the characterization of the noisy Gaussian boson sampling. In the quantum computational advantage regime, we use Bayesian tests and correlation function analysis to validate the samples against all current classical spoofing mockups. Estimating with the best classical algorithms to date, generating a single ideal sample from the same distribution on the supercomputer Frontier would take ∼600 yr using exact methods, whereas our quantum computer, Jiǔzhang 3.0, takes only 1.27 µs to produce a sample. Generating the hardest sample from the experiment using an exact algorithm would take Frontier∼3.1×10^{10} yr.

Surgical management strategy of alimentary tract duplication involving the rectum in children.

PURPOSE: Alimentary tract duplication involving the rectum (ATD-R) is rare. The purpose of the study was to describe the features of pediatric ATD-R patients and propose a surgical management strategy. METHODS: Nine consecutive children operated on for ATD-R at a tertiary center for pediatrics from January 2010 to June 2021 were retrospectively reviewed and followed up. Eighty-six children with the same diagnosis from the literature were reviewed to assist the investigation. Classifications of ATD-R consisted of cystic, tubular, and diverticular. RESULTS: Surgical treatment and histopathological examination identified six females and three males with ATD-R. Initial clinical symptoms included perianal lesions, abnormal discharge, and anorectal malformation (ARM). Apart from one tubular ATD-R patient with cloaca malformation, the other eight patients had normal-developed anorectum. Complete or partial lesion resection maintaining the integrity of the proper colorectum was a principle of surgery. Six patients were followed up for a median time of 71 (range 12-121) months with good prognoses. A surgical management strategy of ATD-R in children was proposed. CONCLUSIONS: ATD-R commonly occurred concurrently with normal-developed anorectum, seldom combined with ARM. ATD-R should be considered as a differential diagnosis in anorectal symptoms. The timely and appropriate operation was curative.

Growth assessments for children with recurrent tracheoesophageal fistulas.

PURPOSE: To assess the growth status of children with recurrent tracheoesophageal fistula (rTEF), and determine the possible risk factors of growth retardation (GR). METHODS: The medical records of 83 patients with rTEF who underwent surgical repair were retrospectively analyzed. The patients were retrospectively divided into two groups according to whether they had GR. The clinical variables were compared between the GR and non-GR groups. Univariate and multivariable logistic regression analysis were performed to identify the risk factors for GR. RESULTS: Eighty-three children diagnosed with rTEF were included in this study. After a median follow-up of 31.4 (19.8, 48.7) months, GR occurred in 28 patients (33.7%). Among them, six patients with only weight for age Z score (WAZ) < -2SD, five patients with only height for age Z score (HAZ) < -2SD, and six patients with only BMI for age Z score (BAZ) < -2SD, while seven patients with both WAZ and HAZ < -2SD and four patients with both WAZ, HAZ and BAZ < -2SD. Multivariate logistic regression analysis showed that birth weight, anastomotic stricture and dysphagia after rTEF repair were independent risk factors with OR of 0.325 (0.119, 0.891), 4.396 (1.451, 13.324) and 5.341 (1.153, 24.752) for GR, respectively. CONCLUSIONS: GR is a common complication after rTEF repair. Birth weight, anastomotic stricture and dysphagia after rTEF repair are independent risk factors affecting growth.

Esophageal elongation by bougienage and delayed primary thoracoscopic anastomosis for pure esophageal atresia without tracheoesophageal fistula.

PURPOSE: We aim to share our experience of esophageal elongation by bougienage and delayed primary thoracoscopic anastomosis for pure esophageal atresia (EA) without tracheoesophageal fistula (TEF). METHODS: Fifteen patients with pure EA treated with delayed primary thoracoscopic anastomosis combined with or without esophageal elongation by bougienage were retrospectively analyzed. RESULTS: Four patients were managed without bougienage, and their surgical repair was performed thoracoscopically after natural esophageal growth. Among the remaining 11 patients, the average tension-free distance before elongation was 5 (4.5-6) vertebral bodies, and the mean age at the start and end of the bougienage period was 123 (63-280) days and 173 (106-350) days, respectively, with an average duration of 50 (29-82) days. The average age at the definitive operation in this series was 184 (107-385) days, with a mean operative duration of 186 (95-300) min. Neither anastomotic leakage nor TEF occurred, and oral feeding was partially or completely established in 13 patients during hospitalization. Among all patients, one was lost to follow-up, and others were followed up with an average duration of 47.7 (9.8-97.1) months. All patients had different degrees of anastomosis stricture, and 8 patients had gastroesophageal reflux. Oral feeding was completely established in 12 patients; however, tube feeding was required in 2 patients. CONCLUSIONS: The management of pure EA is complicated and inconclusive. Esophageal elongation by bougienage and delayed primary thoracoscopic anastomosis for long-gap pure EA without TEF is safe and effective.

Retrospective analysis of pneumothorax after repair of esophageal atresia/tracheoesophageal fistula.

BACKGROUND: To analyze the possible causes, treatment and outcomes of postoperative pneumothorax in patients with Gross type C esophageal atresia/tracheoesophageal fistula (EA/TEF). METHODS: Medical records of patients with Gross type C EA/TEF who were diagnosed and treated in Beijing Children's Hospital from January 2007 to January 2020 were retrospectively collected. They were divided into 2 groups according to whether postoperative pneumothorax occurred. Univariate and multivariate logistic regression analysis were performed to identify risk factors for pneumothorax. RESULTS: A total of 188 patients were included, including 85 (45 %) in the pneumothorax group and 103 (55 %) in the non-pneumothorax group. Multivariate logistic regression analysis showed that postoperative anastomotic leakage [P < 0.001, OR 3.516 (1.859, 6.648)] and mechanical ventilation [P = 0.012, OR 2.399 (1.210, 4.758)] were independent risk factors for pneumothorax after EA/TEF repair. Further analysis of main parameters of mechanical ventilation after surgery showed that none of them were clearly related to the occurrence of pneumothorax. Among the 85 patients with pneumothorax, 33 gave up after surgery and 52 received further treatment [conservative observation (n = 20), pleural puncture (n = 11), pleural closed drainage (n = 9), both pleural puncture and closed drainage (n = 12)]. All of the 52 patients were cured of pneumothorax at discharge. CONCLUSIONS: Anastomotic leakage and postoperative mechanical ventilation were risk factors for pneumothorax after repair of Gross type C EA/TEF, but the main parameters of mechanical ventilation had no clear correlation with pneumothorax. After symptomatic treatment, the prognosis of pneumothorax was good.

Anastomotic stricture indexes for endoscopic balloon dilation after esophageal atresia repair: a single-center study.

We investigated changes in anastomotic stricture indexes (SIs) and stricture diameter (SD) between before and 6 months after the first dilatation in children with anastomotic stricture after esophageal atresia (EA) repair and identified predictors of medium-term dilatation success (success for at least 3 months). We retrospectively reviewed the records and measurement indexes of patients who underwent post-EA repair endoscopic balloon dilatation between November 2017 and August 2019 in our hospital. We identified diagnostic and performance indicators that predicted medium-term dilatation success by univariate and multivariate analyses and receiver operator characteristic (ROC) curve analysis. Sixty patients (34 boys and 26 girls) showed post-EA repair anastomotic stricture. Paired sample t-tests showed that SD (P < 0.001), upper pouch SI (U-SI, P < 0.001), lower pouch SI (L-SI, P < 0.001), upper pouch esophageal anastomotic SI (U-EASI, P < 0.001) and lower pouch EASI (L-EASI, P < 0.001) were significantly better at 6 months after than before the first dilatation. Logistic regression analysis showed that dilatation number (P = 0.002) and U-SI at 6 months after the first dilatation (P = 0.019) significantly predicted medium-term dilatation success. ROC curve analysis revealed that combining U-SI (cut-off value = 55.6%) and dilatation number (cut-off value = 10) had good accuracy in predicting medium-term dilatation success 6 months after the first dilatation (area under the curve-ROC: 0.95). In conclusion, endoscopic balloon dilatation significantly improved SD and SIs in children with post-EA repair anastomotic stricture. Dilatation number and U-SI at 6 months after the first dilatation were useful in predicting medium-term dilatation success and could represent a supplementary method to improve judgment regarding whether further dilatation is needed 6 months after the first dilatation.

Clinical comparison between thoracoscopic and thoracotomy repair of Gross type C esophageal atresia.

BACKGROUND: To compare the clinical outcomes between thoracoscopic approach and thoracotomy surgery in patients with Gross type C Esophageal atresia (EA) and tracheoesophageal fistula (TEF). METHODS: Patients with Gross type C EA/TEF who underwent surgery from January 2007 to January 2020 at Beijing Children's Hospital were retrospectively analyzed. The patients were divided into two groups according to surgical approaches. The perioperative factors and postoperative complications were compared among the two groups. RESULTS: One hundred and ninety patients (132 boys and 58 girls) with a median birth weight of 2975 (2600, 3200) g were included. The primary operations were performed via thoracoscopic (n = 62) and thoracotomy (n = 128) approach. After comparison of clinical characteristics between the two groups, we found that there were statistically significant differences in associated anomalies, method of fistula closure, duration of mechanical ventilation after surgery, feeding option before discharge, management of pneumothorax, and prognosis (all P < 0.05). To a certain extent, thoracoscopic surgery reduced the incidence of anastomotic leakage and increased the incidence of anastomotic stricture in this study. However, there were no statistically significant differences between the two groups in terms of operative time, postoperative pneumothorax, anastomotic leakage, anastomotic stricture, and recurrent tracheoesophageal fistula (all P > 0.05). CONCLUSIONS: Thoracoscopy surgery for Gross type C EA/TEF is a safe and effective, minimally invasive technique with comparable operative time and incidence of postoperative complications.

Thoracoscopic surgery for recurrent tracheoesophageal fistula after esophageal atresia repair.

We aimed to investigate the safety, feasibility, and outcomes of thoracoscopic surgery for recurrent tracheoesophageal fistula (rTEF) after esophageal atresia repair. The medical records and follow-up data of 31 patients who underwent thoracoscopic surgery for rTEF at a single institution were collected and reviewed. In total, 31 patients were enrolled with a median age of 7 months (range: 3-30 months) and a median weight of 6,000 g (range: 4,000-12,000 g) before reoperation. The median operation time for the entire series was 2.9 hours (range: 1.5-7.5 hours), and the median total hospitalization duration after surgery was 19 days (range: 11-104 days). One patient died of anastomotic leakage, a second rTEF, severe malnutrition, and thoracic infection; the mortality rate was 3.23% (1/31). Nine patients (9/31, 29.03%) had an uneventful recovery, and the incidences of postoperative anastomotic leakage, anastomotic stricture, and second rTEF were 25.81%, 61.29%, and 9.68%, respectively. After a median follow-up of 12 months (range: 3-24 months), 26 survivors resumed full oral feeding, 2 were tube fed, 2 required a combination of methods, and 4 patients experienced severe respiratory complications. In total, 9 patients had pathological gastroesophageal reflux, and 2 patients eventually underwent Nissen fundoplication. Of the 30 survivors with growth chart data, the median weight for age Z-score, height for age Z-score, and weight for height Z-score were - 0.46 (range: -5.1 to 2.8), 0.75 (range: -2.7 to 4.7), and - 1.14 (range: -6.8 to 3.0), respectively. Thoracoscopic surgical repair for rTEF is safe, feasible, and effective with acceptable mortality and morbidity.

The roles of extracellular polymeric substances of Pandoraea sp. XY-2 in the removal of tetracycline.

In this study, the roles of extracellular polymeric substances (EPSs) excreted by Pandoraea sp. XY-2 in the removal of tetracycline (TC) were investigated. In the early stage, TC in the solution was mainly removed by the adsorption of EPSs, which accounted for 20% of TC. Thereafter, large amount of TC was transported into the intracellular and biodegraded. EPSs was extracted and the contents of polyprotein and polysaccharides reached their maximum values (30.84 mg/g and 11.15 mg/g) in the first four days. Fourier transform infrared spectroscopy analysis revealed that hydroxyl, methylidyne, methylene and amide I groups in EPSs participated in the adsorption of TC. Furthermore, three-dimensional excitation-emission matrix fluorescence spectroscopy analysis revealed that TC caused the quenching of EPSs fluorescent groups. The quenching mechanism was attributed to static quenching and protein-like substances in EPSs from Pandoraea sp. XY-2 dominated the TC adsorption process. Bioinformatic analysis of Pandoraea sp. XY-2 genome identified multiple genes involved in exopolysaccharide synthesis and EPSs formation. The insights gained in this study might provide a better understanding about the adsorption process of EPSs in tetracycline-contaminated environment.

Deciphering the triclosan degradation mechanism in Sphingomonas sp. strain YL-JM2C: Implications for wastewater treatment and marine resources.

Triclosan (TCS), an antimicrobial agent extensively incorporated into pharmaceuticals and personal care products, poses significant environmental risks because of its persistence and ecotoxicity. So far, a few microorganisms were suggested to degrade TCS, but the microbial degradation mechanism remains elusive. Here, a two-component angular dioxygenase (TcsAaAb) responsible for the initial TCS degradation was characterized in Sphingomonas sp. strain YL-JM2C. Whole-cell biotransformation and crude enzyme assays demonstrated that TcsAaAb catalyzed the conversion of TCS to 4-chlorocatechol and 3,5-dichlorocatechol rather than the commonly suggested product 2,4-dichlorophenol. Then two intermediates were catabolized by tcsCDEF cluster via an ortho-cleavage pathway. Critical residues (N262, F279, and F391) for substrate binding were identified via molecular docking and mutagenesis. Further, TcsAaAb showed activity toward methyl triclosan and nitrofen, suggesting its versatile potential for bioremediation. In addition, TCS-degrading genes were also present in diverse bacterial genomes in wastewater, ocean and soil, and a relatively high gene abundance was observed in marine metagenomes, revealing the transformation fate of TCS in environments and the microbial potential in pollutant removal. These findings extend the understanding of the microbe-mediated TCS degradation and contribute to the mining of TCS-degrading strains and enzymes, as well as their application in the bioremediation of contaminated environments.

Blockade of V-domain immunoglobulin suppressor of T-cell activation reprograms tumour-associated macrophages and improves efficacy of PD-1 inhibitor in gastric cancer.

BACKGROUND AND AIMS: In gastric cancer, the response rate of programmed cell death protein-1 (PD-1) inhibitor is far from satisfactory, indicating additional nonredundant pathways might hamper antitumour immunity. V-domain immunoglobulin suppressor of T-cell activation (VISTA) has been reported in several malignancies as a novel immune-checkpoint. Nevertheless, the role of VISTA in gastric cancer still remains obscure. Our purpose is to explore the clinical significance and potential mechanism of VISTA in affecting gastric cancer patients' survival and immunotherapeutic responsiveness. METHODS: Our study recruited eight independent cohorts with a total of 1403 gastric cancer patients. Immunohistochemistry, multiplex immunofluorescence, flow cytometry or intracellular flow cytometry, quantitative polymerase chain reaction, western blotting, fluorescence-activated cell sorting, magnetic-activated cell sorting, smart-seq2, in vitro cell co-culture and ex vivo tumour inhibition assays were applied to investigate the clinical significance and potential mechanism of VISTA in gastric cancer. RESULTS: VISTA was predominantly expressed on tumour-associated macrophages (TAMs), and indicated poor clinical outcomes and inferior immunotherapeutic responsiveness. VISTA+ TAMs showed a mixed phenotype. Co-culture of TAMs and CD8+ T cells indicated that VISTA+ TAMs attenuated effective function of CD8+ T cells. Blockade of VISTA reprogrammed TAMs to a proinflammatory phenotype, reactivated CD8+ T cells and promoted apoptosis of tumour cells. Moreover, blockade of VISTA could also enhance the efficacy of PD-1 inhibitor, suggesting that blockade of VISTA might synergise with PD-1 inhibitor in gastric cancer. CONCLUSIONS: Our data revealed that VISTA was an immune-checkpoint associated with immunotherapeutic resistance. Blockade of VISTA reprogrammed TAMs, promoted T-cell-mediated antitumour immunity, and enhanced efficacy of PD-1 inhibitor, which might have implications in the treatment of gastric cancer.

Diagnose and treatment for Type D congenital esophageal atresia with tracheoesophageal fistula.

Importance: Type D esophageal atresia (EA) with tracheoesophageal fistula (TEF) is characterized by EA with both proximal and distal TEFs. It is a rare congenital anomaly with a very low incidence. Objective: To investigate diagnostic and treatment strategies for this rare condition. Methods: We retrospectively reviewed the clinicopathological features of patients with EA/TEF treated at our institution between January 2007 and September 2021. Results: Among 386 patients with EA/TEF, 14 (3.6%) had type D EA/TEF. Only two patients were diagnosed with proximal TEF preoperatively. Seven patients were diagnosed intraoperatively. Five patients were missed for diagnosis during the initial surgery but was later confirmed by bronchoscopy. During the neonatal period, seven patients underwent a one-stage repair of proximal and distal TEF via thoracoscopy or thoracotomy. Due to missed diagnosis and other reasons, the other 7 patients underwent two-stage surgery for repair of the proximal TEF, including cervical incision and thoracoscopy. Ten of the 14 patients experienced postoperative complications including anastomotic leakage, pneumothorax, esophageal stricture, and recurrence. Patients who underwent one-stage repair of distal and proximal TEF during the neonatal period showed a higher incidence of anastomotic leak (4/7). In contrast, only one of seven patients with two-stage repair of the proximal TEF developed an anastomotic leak. Interpretation: Type D EA/TEF is a rare condition, and proximal TEFs are easily missed. Bronchoscopy may aim to diagnose and determine the correct surgical approach. A cervical approach may be more suitable for repairing the proximal TEF.

Elucidation of the coumarin degradation by Pseudomonas sp. strain NyZ480.

As a phytotoxin and synthetic chemical, coumarin (COU) is known for its hepatotoxicity and carcinogenicity. However, no thorough characterization of its microbial degradation has been reported. Here, Pseudomonas sp. strain NyZ480 was isolated for its capability of utilizing COU as the sole carbon source. Studies on its growth and degradation efficiency of COU under various conditions suggested that strain NyZ480 performed the optimum degradation at 30 â„ƒ, pH 7, and 0.5 mM COU was completely removed within 4 h with 1% inoculum. HPLC and LC-MS analyses indicated that dihydrocoumarin (DHC), melilotic acid (MA) and 3-(2,3-dihydroxyphenyl)propionate (DHPP) were the upstream biotransformation intermediates of COU. Enzyme assay established that the initial reaction transforming COU to DHC required an NAD(P)H-dependent reductase, followed by the hydrolysis of DHC to generate MA, and the third reaction catalyzing the monooxygenation of MA to DHPP utilized a strict NADH-dependent hydroxylase. Combining genomics and transcriptomics, we proposed that the COU downstream degradation (from DHPP) was catalyzed by enzymes encoded by a gene cluster homologous to the mhp cluster for 3(3-hydroxyphenyl)propionate degradation via DHPP in E. coli. This study thoroughly identified the intermediates from the COU catabolism, providing essential insights into the molecular evidences of its biodegradation pathway.

Clinical characteristics and prognosis of 69 cases of neonatal appendicitis.

Importance: Neonatal appendicitis (NA) is a rare and potentially fatal neonatal disease. However, misdiagnosis is common owing to atypical clinical manifestations and non-specific laboratory tests. Objective: The aim of this study was to summarize the clinical characteristics, treatments, and prognoses of infants with NA. Methods: This retrospective analysis included 69 patients diagnosed with NA admitted to Beijing Children's Hospital between 1980 and 2019. The patients were divided into surgical and non-surgical groups based on whether surgery was performed. Their clinical characteristics were analyzed using the chi-square test, t-test, or the Mann-Whitney U test. Results: The study included 47 males and 22 females with NA. The primary symptoms were abdominal distension (n = 36, 52.2%), fever (n = 19, 27.5%), refusal to feed or decreased feeding (n = 16, 23.2%), and vomiting (n = 15, 21.7%). Sixty-five patients underwent abdominal ultrasound examinations; 43 had definite appendiceal abnormalities, 10 had right lower abdominal adhesive masses, and 14 had neonatal enterocolitis manifestations. Twenty-nine and 40 patients were in the surgical and non-surgical groups, respectively. No statistically significant differences were observed between the groups regarding sex, age at onset, birth weight, admission weight, or hospitalization time. However, parenteral nutrition was prolonged in the surgical group (P = 0.001). Additionally, two patients (2.9%) died. Interpretation: NA is a rare neonatal disease with atypical clinical manifestations. Abdominal ultrasonography may aid in the diagnosis. Similarly, appropriate treatment can improve the prognosis.