Identification and analysis of key circRNAs in the mouse embryonic ovary provides insight into primordial follicle development.

BACKGROUND: CircRNAs are a class of noncoding RNAs with tissue- and development-specific expression characteristics. In many mammals, primordial follicle development begins in the embryonic stage. However, the study of circRNAs in primordial follicle development in mice has not been reported. RESULTS: In this study, ovaries were collected from mouse foetuses at 15.5 days post coitus (dpc) and 17.5 dpc, which are two key stages of primordial follicle development. A total of 4785 circRNAs were obtained by using RNA-seq. Of these, 83 differentially expressed circRNAs were identified. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses showed that these differential circRNAs were mainly involved in the regulation of reproductive development. Through qRT-PCR, back-splice sequence detection and enzyme digestion protection experiments, we found that circ-009346, circ-014674, circ-017054 and circ-008296 were indeed circular. Furthermore, circ-009346, circ-014674 and circ-017054 were identified as three key circRNAs by analysing their expression in the ovaries of mice at different developmental stages. The circRNA-miRNA-mRNA interaction network was constructed and validated for target miRNA and mRNA using qRT-PCR. The interacting genes circ-009346, circ-014674, and circ-017054 were subjected to KEGG enrichment analysis. We found that circ-014674 may participate in the assembly and reserve of primordial follicles through oestrogen and the Janus kinase (JAK) signal transducer and activator of transcription (STAT) signalling pathway (JAK-SATA). Circ-009346 and circ-017054 may have similar functions and are involved in the activation and growth of primordial follicles through the mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K) signalling pathways. CONCLUSIONS: Based on our findings, three circRNAs associated with primordial follicle development were identified, and their potential mechanisms of regulating primordial follicle development were revealed. These findings will help us better understand the molecular mechanism of circRNAs in primordial follicles and provide important references and targets for the development of primordial follicles.

Transrectal Drainage Tube Use for Preventing Postendoscopic Submucosal Dissection Coagulation Syndrome in Patients With Colorectal Lesions: A Multicenter Randomized Controlled Clinical Trial.

INTRODUCTION: Postendoscopic submucosal dissection (ESD) coagulation syndrome (PECS) prevention is one of the common postoperative complications of colorectal ESD. Considering the increasing incidence of PECS, it is critical to investigate various prevention methods. The objective of this study was to evaluate the efficacy of transrectal drainage tubes (TDTs) in PECS prevention in patients following colorectal ESD. METHODS: From July 2022 to July 2023, a multicenter, randomized controlled clinical trial was conducted in 3 hospitals in China. Patients with superficial colorectal lesions ≥20 mm who had undergone ESD for a single lesion were enrolled. Initially, 229 patients were included in the study and 5 were excluded. Two hundred twenty-four were randomly assigned to the TDT and non-TDT group in the end. This open-label study utilized a parallel design with a 1:1 allocation ratio, and endoscopists and patients were not blind to the randomization, and a 24 Fr drainage tube was inserted approximately 10-15 cm above the anus after the ESD under the endoscopy and tightly attached to a drainage bag. The TDTs were removed in 1-3 days following the ESD. RESULTS: A total of 229 eligible patients were enrolled in this study, and 5 patients were excluded. Ultimately, 224 patients were assigned to the TDT group (n = 112) and non-TDT group (n = 112). The median age for the patients was 63.45 years (IQR 57-71; 59 men [52.68%]) in the TDT group and 60.95 years (IQR 54-68; 60 men [53.57%]) in the non-TDT group. Intention-to-treat analysis showed patients in the TDT group had a lower incidence of PECS than patients in the non-TDT group (7 [6.25%] vs 20 [17.86%]; relative risk, 0.350; 95% confidence interval [CI], 0.154-0.795; P = 0.008). In the subgroup analysis, TDTs were found to prevent PECS in patients of the female gender (odd ratio, 0.097; 95% CI, 0.021-0.449; P = 0.001), tumor size <4 cm (odd ratio, 0.203; 95% CI, 0.056-0.728; P = 0.011), tumor located in the left-sided colorectum (odd ratio, 0. 339 95% CI, 0.120-0.957; P = 0.035), and shorter procedure time (<45 minutes) (odd ratio, 0.316; 95% CI, 0.113-0.879; P = 0.023). The tube fell off in 1 case (0.89%) accidentally ahead of time. No TDT-related complication was observed. DISCUSSION: The results from this randomized clinical study indicate that the application of TDTs effectively reduced the incidence of PECS in patients after colorectal ESD ( chictr.org.cn Identifier: ChiCTR2200062164).

Validation and update of a clinical score model to predict technical difficulty of colorectal endoscopic submucosal dissection: a multicenter prospective cohort study.

BACKGROUND AND AIMS: The Zhongshan colorectal endoscopic submucosal dissection (CR-ESD) score model was proposed to grade the technical difficulty of CR-ESD. The objective of this study was to prospectively validate and update the score model. METHODS: A multicenter prospective cohort analysis of CR-ESD was conducted. Individual data on patients, lesions, and outcomes of CR-ESD were used to validate the original model and further refine the difficulty of the prediction model. Data were randomly divided into discovery and internal validation cohorts. A multivariate Cox regression analysis was conducted on the discovery cohort to develop an updated risk-scoring system, which was then validated. RESULTS: Five hundred forty-eight patients with 565 colorectal lesions treated by ESD from 4 hospitals were included. In the prospective validation cohort, the area under the receiver-operating characteristic (ROC) curve for the original model was .707. Six risk factors were identified and assigned point values: tumor size (2 points for 30-50 mm, 3 points for ≥50 mm), at least two-thirds circumference of the lesion (3 points), tumor location in the cecum (2 points) or flexure (2 points), laterally spreading tumor-nongranular lesions (1 point), preceding biopsy sampling (1 point), and NBI International Colorectal Endoscopic type 3 (3 points). The updated model had an area under the ROC curve of .738 in the discovery cohort and of .782 in the validation cohort. Cases were categorized into easy (score = 0-1), intermediate (score = 2-3), difficult (score = 4-6), and very difficult (score ≥7) groups. Satisfactory discrimination and calibration were observed. CONCLUSIONS: The original model achieved an acceptable level of prediction in the prospective cohort. The updated model exhibited superior performance and can be used in place of the previous version. (Clinical trial registration number: ChiCTR2100047087.).

Clinical outcomes of endoscopic resection for the treatment of intermediate- or high-risk gastric small gastrointestinal stromal tumors: a multicenter retrospective study.

BACKGROUND AND AIMS: Many studies of gastric gastrointestinal stromal tumors (g-GISTs) following endoscopic resection (ER) have typically focused on tumor size, with most tumors at low risk of aggressiveness after risk stratification. There have been few systematic studies on the oncologic outcomes of intermediate- or high-risk g-GISTs after ER. METHODS: From January 2014 to January 2020, we retrospectively collected patients considered at intermediate- or high-risk of g-GISTs according to the modified NIH consensus classification system. The primary outcome was overall survival (OS). RESULTS: Six hundred and seventy nine (679) consecutive patients were diagnosed with g-GISTs and treated by ER between January 2014 and January 2020 in three hospitals in Shanghai, China. 43 patients (20 males and 23 females) were confirmed at intermediate-or high-risk. The mean size of tumors was 2.23 ± 1.01 cm. The median follow-up period was 62.02 ± 15.34 months, with a range of 28 to 105 months. There were no recurrences or metastases, even among patients having R1 resections. The 5-year OS rate was 97.4% (42/43). CONCLUSION: ER for intermediate- or high-risk gastric small GISTs is a feasible and safe method, which allows for a wait-and-see approach before determining the necessity for imatinib adjuvant or surgical treatment. This approach to g-GISTs does require that patients undergo close follow-up.

Porphyromonas gingivalis predicts local recurrence after endoscopic submucosal dissection of early esophageal squamous cell carcinoma or precancerous lesion.

BACKGROUND: Porphyromonas gingivalis plays an oncogenic role in development and progression of esophageal squamous cell carcinoma (ESCC). However, the impact of P. gingivalis on local recurrence of early ESCC or precancerous lesion after ESD treatment remains unknown. The present study aimed to evaluate the impact of P. gingivalis on local recurrence after ESD treatment of early ESCC or high-grade dysplasia (HGD). METHODS: The amount of P. gingivalis was assessed by immunohistochemistry in 205 patients with early ESCC or HGD. Univariate and multivariate Cox regression analyses were performed to determine the effect of P. gingivalis on local recurrence. Propensity score matching analysis was performed to reduce the imbalance of baseline characteristics. A nomogram integrating significant prognostic factors was built for local recurrence prediction. RESULTS: The amount of P. gingivalis increased significantly in neoplasms that invaded up to muscularis mucosa and submucosa compared with lesions confined to epithelium or lamina propria. Overabundance of P. gingivalis was positively associated with invasion depth, post-ESD stricture and local recurrence. Univariate and multivariate Cox regression analyses revealed that P. gingivalis, longitudinal length of lesion and lymphovascular invasion were independent predictors for post-ESD recurrence. A nomogram comprising P. gingivalis, lymphovascular involvement, and lesion length performed well for prediction of post-ESD local recurrence with the concordance indices of 0.72 (95%CI, 0.62 to 0.80), 0.72 (95%CI, 0.63 to 0.80), and 0.74 (95%CI, 0.65 to 0.83) in the validation cohort, the entire cohort, and the subcohort after PSM, respectively. CONCLUSION: P. gingivalis overabundance is a risk factor and a potential predictor for local recurrence of early ESCC or HGD after ESD treatment. Thus, clearance of P. gingivalis represents an attractive strategy for prognosis improvement and for prevention of ESCC.

Long-term clinical outcomes of endoscopic submucosal dissection in rectal neuroendocrine tumors based on resection margin status: a real-world study.

BACKGROUND: Endoscopic submucosal dissection (ESD) has been widely adopted in treating rectal neuroendocrine tumors (NETs). However, clinical outcomes in rectal NETs after ESD with different resection margin status remain scanty, particularly in patients with positive resection margins. This study aimed to evaluate the long-term clinical outcomes of ESD in rectal NET based on the resection margin status. METHODS: This retrospective study included 436 patients diagnosed with rectal NET who had undergone ESD. Clinical data, including age, sex, tumor size, stage, invasion, and the resection margin status, were collected. Further, the patients were assessed for complications, recurrence, distant metastasis, and long-term outcomes. RESULTS: Among all 436 patients, 395 patients had their primary ESD in our hospital. Complete resection was achieved in 319 patients. Patients who did not achieve complete resection opted for follow-up (n = 73), salvage surgery (n = 1) and salvage ESD (n = 2). Another 41 had their primary ESD in other hospital with incomplete resection and had salvage ESD in our hospital. All 436 patients had a median follow-up period of 61.4 months (range 33.4-125.3 months). During the follow-up period, two patients developed recurrences, while three patients developed metastasis. There were no significant differences in the 5-year progression-free survival and overall survival between patients with incomplete resection opting for follow-up compared to the other two groups (P = 0.5/0.8). However, the complication rates were significantly higher in patients who received salvage ESD. CONCLUSION: This study demonstrated that positive resection margins have no influence on survival in patients with rectal NET treated using ESD.

Identification of the regulatory network and potential markers for type 2 diabetes mellitus related to internal exposure to metals in Chinese adults.

People intake metals from their environment. This study investigated type 2 diabetes mellitus (T2DM) related to internal exposure to metals and attempted to identify possible biomarkers. A total of 734 Chinese adults were enrolled, and urinary levels of ten metals were measured. Multinomial logistic regression model was used to assess the association between metals and impaired fasting glucose (IFG) and T2DM. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and protein-protein interaction were used to explore the pathogenesis of T2DM related to metals. After adjustment, lead (Pb) was positively associated with IFG (odds ratio [OR] 1.31, 95% confidence interval [CI] 1.06-1.61) and T2DM (OR 1.41, 95% CI 1.01-1.98), but cobalt was negatively associated with IFG (OR 0.57, 95% CI 0.34-0.95). Transcriptome analysis showed 69 target genes involved in the Pb-target network of T2DM. GO enrichment indicated that the target genes are enriched mainly in the biological process category. KEGG enrichment indicated that Pb exposure leads to non-alcoholic fatty liver disease, lipid and atherosclerosis, and insulin resistance. Moreover, there is alteration of four key pathways, and six algorithms were used to identify 12 possible genes in T2DM related to Pb. SOD2 and ICAM1 show strong similarity in expression, suggesting a functional correlation between these key genes. This study reveals that SOD2 and ICAM1 may be potential targets of Pb exposure-induced T2DM and provides novel insight into the biological effects and underlying mechanism of T2DM related to internal exposure to metals in the Chinese population.

Triaxially strained suspended graphene for large-area pseudo-magnetic fields.

Strain-engineered graphene has garnered much attention recently owing to the possibilities of creating substantial energy gaps enabled by pseudo-magnetic fields (PMFs). While theoretical works proposed the possibility of creating large-area PMFs by straining monolayer graphene along three crystallographic directions, clear experimental demonstration of such promising devices remains elusive. Herein, we experimentally demonstrate a triaxially strained suspended graphene structure that has the potential to possess large-scale and quasi-uniform PMFs. Our structure employs uniquely designed metal electrodes that function both as stressors and metal contacts for current injection. Raman characterization and tight-binding simulations suggest the possibility of achieving PMFs over a micrometer-scale area. Current-voltage measurements confirm an efficient current injection into graphene, showing the potential of our devices for a new class of optoelectronic applications. We also theoretically propose a photonic crystal-based laser structure that obtains strongly localized optical fields overlapping with the spatial area under uniform PMFs, thus presenting a practical route toward the realization of graphene lasers.

The Essential Role of Epigenetic Modifications in Neurodegenerative Diseases with Dyskinesia.

Epigenetics play an essential role in the occurrence and improvement of many diseases. Evidence shows that epigenetic modifications are crucial to the regulation of gene expression. DNA methylation is closely linked to embryonic development in mammalian. In recent years, epigenetic drugs have shown unexpected therapeutic effects on neurological diseases, leading to the study of the epigenetic mechanism in neurodegenerative diseases. Unlike genetics, epigenetics modify the genome without changing the DNA sequence. Research shows that epigenetics is involved in all aspects of neurodegenerative diseases. The study of epigenetic will provide valuable insights into the molecular mechanism of neurodegenerative diseases, which may lead to new treatments and diagnoses. This article reviews the role of epigenetic modifications neurodegenerative diseases with dyskinesia, and discusses the therapeutic potential of epigenetic drugs in neurodegenerative diseases.

Simultaneous endoscopic submucosal dissection for synchronous multiple early esophageal squamous cell carcinoma: a propensity score-matched analysis.

BACKGROUND: The clinical effect of endoscopic submucosal dissection (ESD) in the treatment of early esophageal squamous cell carcinoma (EESCC) is widely recognized. However, the long-term treatment outcome of simultaneous ESD for multiple EESCC currently remained unknown. Hence, this study was aimed at further evaluating the long-term outcome of simultaneous ESD for synchronous multiple EESCC by comparing with ESD for single EESCC. METHODS: Consecutive patients who underwent ESD for EESCC from June 2008 to June 2018 were included. Propensity score-matched analysis was used to compensate for the differences in age, sex, tumor location, tumor size, and tumor invasion depth between simultaneous and single ESD groups. Treatment outcomes including en bloc resection rate, curative resection rate, complication rate, and long-term outcomes including overall survival (OS), recurrence-free survival (RFS), metachronous recurrence were compared between the 2 groups after matching. RESULTS: The propensity score-matched analysis included 332 lesions (166 patients) and 332 lesions (332 patients) in simultaneous and single ESD groups, respectively. Among all the outcomes, en bloc resection, curative resection, 5-year OS, and 5-year RFS rates were comparable. Complications were more common in the simultaneous ESD group (15.06% vs. 9.64%, P = 0.073). The 5-year metachronous recurrence rates were significantly high in the simultaneous ESD groups (24.28% vs. 6.99%). CONCLUSIONS: Simultaneous ESD is an effective and safe methodology for synchronous multiple EESCC; it also reduces hospital stay and medical expenses. The risk of metachronous recurrence is higher for patients with synchronous multiple EESCC; thus, more intensive strategies are required.

Overexpression and Characterization of a Novel Plant Carotenoid Cleavage Dioxygenase 1 from Morus notabilis.

Synthesis of ß-ionone in microbial cell factories is limited by the efficiency of carotenoid cleavage dioxygenases (CCDs). To obtain genes responsible for specific cleavage of carotenoids generating ß-ionone, a novel carotenoid cleavage dioxygenase 1 from Morus notabilis was cloned and overexpressed in Escherichia coli. The MnCCD1 protein was able to cleave a variety of carotenoids at the positions 9, 10 (9', 10') to produce ß-ionone, 3-hydroxy-4-oxo-ß-ionone, 3-hydroxy-ß-ionone, and 3-hydroxy-α-ionone in vitro. MnCCD1 could also cleave lycopene and ß-carotene at the 9, 10 (9', 10') bind bond to produce pseudoionone and ß-ionone, respectively, in E. coli accumulating carotenoids. The enzyme activity of MnCCD1 was reached 2.98 U/mL at optimized conditions (temperature 28 °C, IPTG 0.1 mM, induction time 24 h). The biochemical characterization of MnCCD1 revealed the optimal activities were at pH 8.4 and 35 °C. The addition of 10 % ethanol could increase enzyme activity at above 15 %. However, an obvious decline was observed on enzyme activity as the concentration of Fe2+ increased (0-1 mM). The Vmax for ß-apo-8'-carotenal was 72.5 U/mg, while the Km was 0.83 mM. The results provide a foundation for developing the application of carotenoid cleavage dioxygenases as biocatalysis and synthetic biology platforms to produce volatile aroma components from carotenoids.

Cloning and Characterization of a Novel Carotenoid Cleavage Dioxygenase 1 from Helianthus annuus.

Natural ß-ionone, a high-value flavoring agent, has been widely applied in the food, cosmetics, and perfume industry. However, attempts to overproduce ß-ionone in microorganisms have been limited by the efficiency of carotenoid cleavage dioxygenases (CCDs), which catalyzes ß-carotene in the biosynthesis pathway. In order to obtain CCD genes responsible for the specific cleavage of carotenoids generating ß-ionone, a novel carotenoid cleavage dioxygenase 1 from Helianthus annuus was cloned and overexpressed in Escherichia coli BL21(DE3). The recombinant CCD was able to cleave a variety of carotenoids at the 9, 10 (9', 10') sites to produce C13 products in vitro, including ß-ionone, pseudoionone, 3-hydroxy-4-oxo-ß-ionone, 3-hydroxy-ß-ionone, and 3-hydroxy-α-ionone, which vary depending on the carotenoid substrates. In comparison with lycopene and zeaxanthin, HaCCD1 also showed the high specificity for ß-carotene to cleave the 9, 10 (9', 10') double bond to produce ß-ionone in E. coli accumulating carotenoids. Finally, the expression of HaCCD1 in E. coli was optimized, and biochemical characterizations were further clarified. The optimal activity of HaCCD1 was at pH 8.8 and 50 °C. The Vmax for ß-apo-8'-carotenal was 10.14 U/mg, while the Km was 0.32 mM. Collectively, our study provides a valuable enzyme for the synthesis of natural ß-ionone by biotransformation and synthetic biology platform.

One-pot synthesis of dihydro-ß-ionone from carotenoids using carotenoid cleavage dioxygenase and enoate reductase.

Dihydro-ß-ionone is a characteristic aroma compound of Osmanthus fragrans and is widely applied in the flavor & fragrance industry. However, the main focus is on chemical synthesis due to the metabolic pathways of dihydro-ß-ionone is still unclear. Here, we explored the one-pot synthesis system for dihydro-ß-ionone production using carotenoid cleavage dioxygenase (CCD) and enoate reductase. After screening the CCD enzyme, PhCCD1 from the Petunia hybrid was identified as the suitable enzyme for the first step of dihydro-ß-ionone synthesis due to the high enzyme activity for carotenoid. The PhCCD1 was expressed in Escherichia coli and further characterized. The optimal activity of PhCCD1 was observed at pH 6.8 and 45 °C. The enzyme was stable over the pH range of 6.0-8.0 and had good thermal stability below 40 °C. Then, we optimized the coupled reaction conditions for dihydro-ß-ionone production by PhCCD1 and enoate reductase AaDBR1 from Artemisia annua. Furthermore, we introduced the NADPH regeneration system with a 1.5-fold enhancement for dihydro-ß-ionone production. Collectively, approximately 13.34 mg/L dihydro-ß-ionone was obtained by the one-pot biosystem with a corresponding molar conversion of 85.8%. For the first time, we successfully designed and constructed a new synthesis pathway for dihydro-ß-ionone production in vitro. The coupled catalysis reported herein illustrates the feasibility of producing dihydro-ß-ionone from carotenoids and guides further engineering in the food industry.

HDAC2 promotes the EMT of colorectal cancer cells and via the modular scaffold function of ENSG00000274093.1.

Histone deacetylase 2 (HDAC2), a member of the Histone deacetylase family, plays a vital role in various carcinomas. In this study, we identified that HDAC2 expression levels are associated with liver metastasis, higher T stages and poor prognosis in colorectal cancer. HDAC2 down-regulation via lentivirus-mediated expression of HDAC2-targeting shRNA reduced the in vitro migration and invasion ability of HCT116 cell as well as their liver metastasis in nude mouse xenografts. Mechanistically, HDAC2 promotes epithelial-mesenchymal transition (EMT) in colorectal cancer cells by combining HDAC1 with EZH2 (a key histone methyltransferase), possibly through the modular scaffold function of a new lncRNA, ENSG00000274093.1. HDAC2 thus appears to promote CRC cell migration and invasion through binding HDAC1 and EZH2 via ENSG00000274093.1.

Frequency-tunable terahertz graphene laser enabled by pseudomagnetic fields in strain-engineered graphene.

Graphene-based optoelectronic devices have recently attracted much attention for the next-generation electronic-photonic integrated circuits. However, it remains elusive whether it is feasible to create graphene-based lasers at the chip scale, hindering the realization of such a disruptive technology. In this work, we theoretically propose that Landau-quantized graphene enabled by strain-induced pseudomagnetic field can become an excellent gain medium that supports lasing action without requiring an external magnetic field. Tight-binding theory is employed for calculating electronic states in highly strained graphene while analytical and numerical analyses based on many-particle Hamiltonian allow studying detailed microscopic mechanisms of zero-field graphene Landau level laser dynamics. Our proposed laser presents unique features including a convenient, wide-range tuning of output laser frequency enabled by changing the level of strain in graphene gain media. The chip-scale graphene laser may open new possibilities for graphene-based electronic-photonic integrated circuits.

Plasmonic nanocavity for obtaining bound state in the continuum in silicon waveguides.

Bound states in the continuum (BICs) have become a new trend in the area of metaoptics and nanophotonics. Strong interactions in electromagnetic fields are analogous to electron transitions in atoms, giving rise to BICs with vanishing radiative losses. However, it is still a great challenge to realize BICs in the lossy plasmonic systems. For this problem, we propose a supercavity-like plasmonic nanocavity consisting of an Au nanorod deposited inside an Au symmetric split ring, and explore the possibility of exciting quasi-BICs that own finite but high quality (Q) factors. In such hybrid configuration, the excited resonances can be easily engineered by modifying the rotation angle or the length of the Au nanorod. With the integration of such nanocavity in silicon (Si) waveguides, sharp transmission spectra could be achieved with fiber-chip in-parallel excitations and detections. Besides, the ultracompact geometry of this plasmonic nanocavity provides a route to boost enhanced electric fields, thus improving sensing performances significantly. Our study not only offers a novel platform for the realization of chip-scale quasi-BICs, but extends functionalities of photonic-plasmonic hybrid circuits.

Prediction of technically difficult endoscopic submucosal dissection for large superficial colorectal tumors: a novel clinical score model.

BACKGROUND AND AIMS: Endoscopic submucosal dissection (ESD) is a promising technique for removing superficial GI tumors, but ESD is technically difficult. The aim of this study was to establish a clinical score model for grading technically difficult colorectal ESD. METHODS: Data on patients, lesions, and outcomes of colorectal ESD at 2 centers were analyzed. The objective parameter of successful ESD within 60 minutes was set as an endpoint to evaluate the difficulty. Independent predictors of difficulty in the derivation cohort were identified by multiple logistic regression analysis and used to develop a clinical score. We validated the score model in the validation cohort. RESULTS: The clinical score comprised tumor size of 30 to 50 mm (1 point) or ≥50 mm (2 points), at least two-thirds circumference of the lesion (2 points), location in the cecum (1 point), flexure (2 points) or dentate line (1 point), and laterally spreading tumor nongranular lesions (1 point). Areas under the receiver operator characteristic curves for the score model were comparable (derivation [.70] vs internal validation [.69] vs external validation [.69]). The probability of successful ESD within 60 minutes in easy (score = 0), intermediate (score = 1), difficult (score = 2-3), and very difficult (score ≥4) categories were 75.0%, 51.3%, 35.6%, and 3.4% in the derivation cohort; 73.3%, 47.9%, 31.8%, and 16.7% in the internal validation cohort; and 79.5%, 66.7%, 43.3%, and 20.0% in the external validation cohort, respectively. CONCLUSIONS: This clinical score model accurately predicts the probability of successful ESD within 60 minutes and can be applied to grade the technical difficulty before the procedure.

High-level expression of a novel multifunctional GH3 family ß-xylosidase/α-arabinosidase/ß-glucosidase from Dictyoglomus turgidum in Escherichia coli.

A novel ß-xylosidase Dt-2286 from Dictyoglomus turgidum was cloned and overexpressed in Escherichia coli BL21 (DE3). Dt-2286 belonging to glycoside hydrolase (GH) family 3 encodes a polypeptide with 762 amino acid residues with a molecular weight of 85.1 kDa. By optimization of the growth and induction conditions, the activity of ß-xylosidase reached 273 U/mL, which is the highest yield reported to date from E. coli in a shake-flask. The optimal activities of the purified Dt-2286 were found at pH 5.0 and 98 °C. It also shows excellent thermostable/haloduric/organic solvent-tolerance. Dt-2286 was revealed to be a multifunctional enzyme with ß-xylosidase, α-arabinofuranoside, α-arabinopyranoside and ß-glucosidase activities, and Kcat/Km was 5245.316 mM-1 s-1, 2077.353 mM-1 s-1, 1626.454 mM-1 s-1, and 470.432 mM-1 s-1 respectively. Dt-2286 showed significant synergistic effects on the degradation of xylans, releasing more reduced sugars (up to 15.08 fold) by simultaneous addition with endoxylanase. Moreover, this enzyme has good activity in the hydrolysis of epimedium B, demonstrating its versatility in practical applications.

Risk factors for delayed bleeding after endoscopic submucosal dissection of colorectal tumors.

AIM: To investigate the risk factors for delayed bleeding following endoscopic submucosal dissection (ESD) for colorectal neoplasms. METHODS: We retrospectively reviewed the medical records of 991 consecutive patients who underwent ESD for colorectal neoplasms at our hospital from January 2007 to November 2016. Delayed post-ESD bleeding was defined as bleeding within 6 h to 30 days after ESD that resulted in either of the three situations: overt hematochezia, bleeding spots confirmed by repeat colonoscopy, or the requirement of a blood transfusion. Delayed bleeding was furtherly separated into early and late delayed bleeding by the end of post-ESD day 2. We analyzed the relationship between delayed bleeding and candidate factors including patient-, lesion-, and treatment-related details. RESULTS: Delayed post-ESD bleeding was found in 47 patients (4.7%), of which 18 cases were late delayed bleeding. Among all patients, 14 patients required a second colonoscopy, and 2 other patients were transferred to surgery. Univariate analysis revealed that patients with hypertension (p = 0.017) and using hot biopsy forceps for wound management (p = 0.028) were significantly associated with late delayed bleeding. Both risk factors remained significant after multivariate analysis: hypertension (OR 2.829, 95% CI 1.101-7.265, p = 0.031), hot biopsy forceps (OR 2.873, 95% CI 1.013-8.147, p = 0.047). Using hot biopsy forceps was also the significant risk factor for late delayed bleeding compared with early delayed bleeding. CONCLUSION: Patient with hypertension and using hot biopsy forceps for wound management during procedure call for attention on high risk of delayed post-ESD bleeding. Therefore, additional perioperative treatment is recommended in patients with these risk factors.

Research progress on the effect of Di-(2-ethylhexyl) phthalate (DEHP) on reproductive health at different periods in life.

Di-(2-ethylhexyl) phthalate (DEHP) is a representative endocrine-disrupting chemical (EDC) that has reproductive, developmental, neurological and immune toxicity in humans and rodents, of which damage to the reproductive system is the most serious. However, exposure to DEHP at different stages of life may produce different symptoms. Studies on this substance are also controversial. This review describes the reproductive effects of DEHP in males and females at different life stages, including infancy, childhood and adulthood.