Comprehensive Understanding of the Heavy Oil Combustion Process: Reaction Behavior, Kinetic Triplet, and Mechanism Implication.

In this work, thermo-oxidative behavior, kinetic triplet, and free radical mechanism of ultraheavy oil during an in situ combustion (ISC) process were systematically surveyed via multiple thermal analysis techniques (TG/DTG/DSC/PDSC), model-free methods, and related mathematical simulation. First, specific mass loss, exothermic intensity, and corresponding temperature intervals were respectively determined in low-/high-temperature oxidation (LTO/HTO) regions. In addition, the comparison of atmospheric/pressurized differential scanning calorimetry (DSC/PDSC) experiments indicated that the pressurized conditions could obviously strengthen the oxidation progress with more heat emission. Then two model-free methods were contrastively employed for PDSC data to calculate LTO and HTO activation energy variations with the conversion rate. Moreover, the acceleratory rate model for LTO and the Sestak-Berggren model for HTO were accordingly picked as the most probable mechanism functions, which were later used to determine the simulated curves. Then, the simulations of α-T and dα/dT-T curves were respectively attained using Friedman equation in MATLAB software and contrasted with experimental data to validate the accuracy of the yielded kinetic triplet and forecast the combustion behavior. Further, the evolution pathways of the underlying oxidation mechanism was illustrated. This study updates the understanding of the nonisothermal combustion process, contributing to the subsequent numerical simulation and feasible investigation for in situ combustion implementation to enhance heavy oil recovery.

Neoadjuvant chemoradiation therapy combined with immunotherapy for microsatellite stable ultra-low rectal cancer (CHOICE II): study protocol of a multicentre prospective randomised clinical trial.

INTRODUCTION: Neoadjuvant chemoradiotherapy (nCRT) could bring tumour shrinking and downstaging and increase the probability of organ preservation for patients with low rectal cancer. But for ultra-low rectal cancer, there is little possibility for organ preservation. Immunotherapy has been shown to have significant survival benefits in microsatellite instability-high patients but poor response in microsatellite stable (MSS) patients. Studies have demonstrated that radiotherapy and immunotherapy have synergistic effects in cancer treatment. There is no existing evidence about the clinical efficacy of immunotherapy combined with nCRT for patients with MSS ultra-low rectal cancer. METHOD AND ANALYSIS: This trial is an open-labelled multicentre prospective randomised controlled trial (NCT05215379) with two parallel groups and allocation ratio 1:1 (nCRT+immunotherapy vs nCRT group). Eligible participants will be aged 18-75 years, with a desire for anus preservation, confirmed cT1-3aN0-1M0 rectal adenocarcinoma, confirmed MSS type, inferior margin of ≤5 cm from the anal verge. The primary endpoint of this trial is complete clinical response (cCR) rate. Immunotherapy is added after 1 week of chemoradiotherapy for two cycles, and then the patients will be administered two cycles of immunotherapy and CAPOX. The evaluations will be carried out after the completion of the whole neoadjuvant therapy. We expect the programme to improve the cCR rate and the quality of life for patients with ultra-low rectal cancer. ETHICS AND DISSEMINATION: This trial was approved by the Ethics committee of Changhai Hospital and other medical centres (Grant number:CHEC2022-118). The results of this study will provide further insight into the clinical efficacy of immunotherapy in combination with nCRT in patients with MSS ultra-low rectal cancer. TRIAL REGISTRATION NUMBER: NCT05215379.

Clinicopathological features and prognosis of synchronous and metachronous colorectal cancer: a retrospective cohort study.

BACKGROUND: To investigate the clinicopathological features and prognosis of synchronous and metachronous multiple primary colorectal cancer. MATERIALS AND METHODS: Patients who underwent operation for synchronous and metachronous colorectal cancer at the colorectal surgery department of Shanghai Changhai Hospital between January 2000 and December 2021 were included. Perioperative indicators were comprehensively compared and included in the survival analyses. RESULTS: In total, 563 patients with synchronous ( n =372) and metachronous ( n =191) colorectal cancer were included. Patients with synchronous colorectal cancer were more likely to have a long onset time, positive carcinoembryonic antigen, advanced TNM stage, large tumor, perineural invasion, p53 high expression, and mismatch repair proficient. Compared with metachronous colorectal cancer, patients with synchronous colorectal cancer showed worse 5-year overall survival (68.6±3.0% vs 81.9±3.5%, P =0.018) and 5-year disease-free survival (61.2±3.1% vs 71.0±3.9%, P =0.022). In the subgroup analysis, segmental resection was an independent risk factor for the long-term outcomes of bilateral synchronous colorectal cancer. CONCLUSIONS: Clinicopathological and molecular features were different between synchronous and metachronous colorectal cancer. Patients with synchronous colorectal cancer showed a worse prognosis than those with metachronous colorectal cancer. Bilateral synchronous colorectal cancer requires extended resection to achieve improved long-term outcomes.

Comparison of functional and oncological outcome of conformal sphincter preservation operation, low anterior resection, and abdominoperineal resection in very low rectal cancer: a retrospective comparative cohort study with propensity score matching.

PURPOSE: Conformal sphincter preservation operation (CSPO) procedure is a sphincter preservation procedure for preserving the anal canal function for very low rectal cancers. This study investigated the functional and oncological outcome of conformal sphincter preservation operation by comparing with low anterior resection (LAR) and abdominoperineal resection (APR). METHODS: This is a retrospective comparative study. Patients who received conformal sphincter preservation operation (n = 52), low anterior resection (n = 54), or abdominoperineal resection (n = 69) were included between 2011 and 2016 in a tertiary referral hospital. Propensity score matching was applied to adjust the baseline characteristics which may influence the choice of the surgical procedure. RESULTS: Twenty-one pairs of conformal sphincter preservation operation vs. low anterior resection and 29 pairs of conformal sphincter preservation operation vs. abdominoperineal resection were selected. The first group had a higher tumor location than the second group. Compared with the low anterior resection group, the conformal sphincter preservation operation group had shorter distal resection margins; however, no significant differences were identified in daily stool frequency, Wexner incontinence score, local recurrence, distant metastasis, overall survival, and disease-free survival between both groups. Compared with the abdominoperineal resection group, the conformal sphincter preservation operation group had shorter operative time and shorter postoperative hospital stay. No significant differences were identified in local recurrence, distant metastasis, overall survival, and disease-free survival. CONCLUSION: Conformal sphincter preservation operation is oncologically safe compared to APR and LAR, and has similar functional findings to LAR. Studies comparing CSPO with intersphincteric resection should be performed.

NDUFV1 attenuates renal ischemia-reperfusion injury by improving mitochondrial homeostasis.

Impaired mitochondrial function and dysregulated energy metabolism have been shown to be involved in the pathological progression of kidney diseases such as acute kidney injury (AKI) and diabetic nephropathy. Hence, improving mitochondrial function is a promising strategy for treating renal dysfunction. NADH: ubiquinone oxidoreductase core subunit V1 (NDUFV1) is an important subunit of mitochondrial complex I. In the present study, we found that NDUFV1 was reduced in kidneys of renal ischemia/reperfusion (I/R) mice. Meanwhile, renal I/R induced kidney dysfunction as evidenced by increases in BUN and serum creatinine, severe injury of proximal renal tubules, oxidative stress, and cell apoptosis. All these detrimental outcomes were attenuated by increased expression of NDUFV1 in kidneys. Moreover, knockdown of Ndufv1 aggravated cell insults induced by H2 O2 in TCMK-1 cells, which further confirmed the renoprotective roles of NDUFV1. Mechanistically, NDUFV1 improved the integrity and function of mitochondria, leading to reduced oxidative stress and cell apoptosis. Overall, our data indicate that NDUFV1 has an ability to maintain mitochondrial homeostasis in AKI, suggesting therapies by targeting mitochondria are useful approaches for dealing with mitochondrial dysfunction associated renal diseases such as AKI.

Case report: Chronic lymphocytic leukemia/small lymphocytic lymphoma and monomorphic epitheliotropic intestinal T-cell lymphoma: A composite lymphoma.

Background: Composite lymphomas involving B-cell and T-cell lymphomas is very rare. Case presentation: We reported a 63-year-old gentleman with composite chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) and monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL). The patient was admitted to our hospital due to abdominal pain, and was diagnosed with CLL/SLL after bone marrow (BM) biopsy, BM aspiration, and flow cytometry. Two weeks later, he was diagnosed with MEITL based on pathological analysis after intestine excision. Next gene sequencing (NGS) findings identified two hotspot mutation sites (STAT5B and DNMT3A) closely related with the pathogenesis of CLL/SLL and MEILT. Additionally, BCOR mutation was only detected in the CLL/SLL area. The likely pathogenic mutations of CLL were SETD2, NOTCH1, SF3B1, and PTPN11, while the likely pathogenic mutations related with the MEILT were TET2 and ZRSR2. Mutations of GATA3, PLCG2, and FAT1 were identified in both CLL/SLL and MEITL areas, but the clinical significance was unknown. Finally, the patient died in the 12-month follow-up after surgery. Conclusion: We report a rare case of composite CLL/SLL and MEITL that highlights the importance of careful inspection of hematologic neoplasms. We also present the results of NGS of different gene mutations in CLL and MEITL tissues.

Development and Validation of an 8-Gene Signature to Improve Survival Prediction of Colorectal Cancer.

Background: Most prognostic signatures for colorectal cancer (CRC) are developed to predict overall survival (OS). Gene signatures predicting recurrence-free survival (RFS) are rarely reported, and postoperative recurrence results in a poor outcome. Thus, we aim to construct a robust, individualized gene signature that can predict both OS and RFS of CRC patients. Methods: Prognostic genes that were significantly associated with both OS and RFS in GSE39582 and TCGA cohorts were screened via univariate Cox regression analysis and Venn diagram. These genes were then submitted to least absolute shrinkage and selection operator (LASSO) regression analysis and followed by multivariate Cox regression analysis to obtain an optimal gene signature. Kaplan-Meier (K-M), calibration curves and receiver operating characteristic (ROC) curves were used to evaluate the predictive performance of this signature. A nomogram integrating prognostic factors was constructed to predict 1-, 3-, and 5-year survival probabilities. Function annotation and pathway enrichment analyses were used to elucidate the biological implications of this model. Results: A total of 186 genes significantly associated with both OS and RFS were identified. Based on these genes, LASSO and multivariate Cox regression analyses determined an 8-gene signature that contained ATOH1, CACNB1, CEBPA, EPPHB2, HIST1H2BJ, INHBB, LYPD6, and ZBED3. Signature high-risk cases had worse OS in the GSE39582 training cohort (hazard ratio [HR] = 1.54, 95% confidence interval [CI] = 1.42 to 1.67) and the TCGA validation cohort (HR = 1.39, 95% CI = 1.24 to 1.56) and worse RFS in both cohorts (GSE39582: HR = 1.49, 95% CI = 1.35 to 1.64; TCGA: HR = 1.39, 95% CI = 1.25 to 1.56). The area under the curves (AUCs) of this model in the training and validation cohorts were all around 0.7, which were higher or no less than several previous models, suggesting that this signature could improve OS and RFS prediction of CRC patients. The risk score was related to multiple oncological pathways. CACNB1, HIST1H2BJ, and INHBB were significantly upregulated in CRC tissues. Conclusion: A credible OS and RFS prediction signature with multi-cohort and cross-platform compatibility was constructed in CRC. This signature might facilitate personalized treatment and improve the survival of CRC patients.

Resveratrol ameliorates muscle atrophy in chronic kidney disease via the axis of SIRT1/FoxO1.

Chronic kidney disease (CKD) is often associated with muscle atrophy. However, the underlying molecular mechanisms are still not well understood. Here, we treated 5/6-nephrectomized (5/6Nx) rats with resveratrol and found that this treatment greatly improves renal function as evidenced by reduced proteinuria and cystatin C. Moreover, resveratrol ameliorates renal fibrosis by reducing transforming growth factor ß (TGF-ß) and connective tissue growth factor (CTGF). Meanwhile, muscle atrophy in these 5/6Nx rats was largely attenuated by resveratrol. Immunoprecipitation revealed that SIRT1 physically interacts with FoxO1 in muscle, and this interaction was weakened in 5/6Nx rats. As a consequence, acetylated FoxO1 was increased in muscle of 5/6Nx rats. The application of resveratrol markedly reverses this trend. These data point out that SIRT1 is a key factor for linking renal disease and muscle atrophy. Indeed, both renal dysfunction and muscle atrophy were further aggravated by 5/6Nx in Sirt1+/- mice. Taken together, our data indicate that SIRT1 plays a pivotal role in muscle atrophy in CKD, and FoxO1 might be a substrate of SIRT1 in this process. Furthermore, resveratrol, together with other agonists of SIRT1, may hold great therapeutic potentials for treating CKD and its related muscle atrophy.

The Classification and Surgical Treatments in Adult Hirschsprung's Disease: A Retrospective Study.

Purpose: To explore the treatments and short-term effects of different types of adult Hirschsprung's disease. Methods: 89 patients treated in Shanghai Changhai Hospital were retrospectively analyzed. According to the patient's medical history, clinical manifestations, auxiliary examination and postoperative pathological results, the patients were divided into adult congenital megacolon, adult idiopathic megacolon, ganglion cell deficiency (types I and II), toxic megacolon and iatrogenic megacolon, The Treatment methods and short-term prognosis of patients in each group were summarized. Results: 41 cases of Hirschsprung's disease in adults and low anterior resection or pull-out low anterior resection was performed, and 35 patients with idiopathic Megacolon were treated with one-stage subtotal colon resection under the condition of adequate preoperative preparation. Some patients admitted for emergency intestinal obstruction received conservative treatment first or underwent elective surgery after colonoscopic decompression was improved; two patients with ganglion cell deficiency subtotal colectomy were performed to remove the dilated proximal bowel segment and the narrow distal bowel segment; three patients with toxic Hirschsprung's disease underwent colostomy in mild cases, while subtotal colorectal resection was required in severe cases; Iatrogenic megacolon was diagnosed in eight cases and the optimum operation should be selected according to the specific conditions of patients. Conclusion: Adult Hirschsprung's diseases were divided into adult congenital hirschsprung's disease, idiopathic Hirschsprung's disease, ganglion cell deficiency, toxic hirschsprung's disease, and iatrogenic Hirschsprung's disease. Different types of surgical treatments for Hirschsprung's disease in adults should be selected according to the specific diagnosis. All patients with adult Hirschsprung's diseases have good short-term outcomes after surgical treatment.

Evaluation of the learning curve for conformal sphincter preservation operation in the treatment of ultralow rectal cancer.

BACKGROUND: To investigate the learning curve of conformal sphincter preservation operation (CSPO) in the treatment of ultralow rectal cancer and to further explore the influencing factors of operation time. METHODS: From August 2011 to April 2020, 108 consecutive patients with ultralow rectal cancer underwent CSPO by the same surgeon in the Department of Colorectal Surgery of Changhai Hospital. The moving average and cumulative sum control chart (CUSUM) curve were used to analyze the learning curve. The preoperative clinical baseline data, postoperative pathological data, postoperative complications, and survival data were compared before and after the completion of learning curve. The influencing factors of CSPO operation time were analyzed by univariate and multivariate analysis. RESULTS: According to the results of moving average and CUSUM method, CSPO learning curve was divided into learning period (1-45 cases) and learning completion period (46-108 cases). There was no significant difference in preoperative clinical baseline data, postoperative pathological data, postoperative complications, and survival data between the two stages. Compared with the learning period, the operation time (P < 0.05), blood loss (P < 0.05), postoperative flatus and defecation time (P < 0.05), liquid diet time (P < 0.05), and postoperative hospital stay (P < 0.05) in the learning completion period were significantly reduced, and the difference was statistically significant. Univariate and multivariate analysis showed that distance of tumor from anal verge (≥ 4cm vs. < 4cm, P = 0.039) and T stage (T3 vs. T1-2, P = 0.022) was independent risk factors for prolonging the operation time of CSPO. CONCLUSIONS: For surgeons with laparoscopic surgery experience, about 45 cases of CSPO are needed to cross the learning curve. At the initial stage of CSPO, beginners are recommended to select patients with ultralow rectal cancer whose distance of tumor from anal verge is less than 4 cm and tumor stage is less than T3 for practice, which can enable beginners to reduce the operation time, accumulate experience, build self-confidence, and shorten the learning curve on the premise of safety.

Pelvic floor peritoneum reconstruction is a protective factor for defecation dysfunction after laparoscopic anterior resection in patients with middle and low rectal cancer.

PURPOSE: The pelvic cavity is a monolithic structure whose integrity plays an important role in the pelvic organ function. Currently, pelvic floor peritoneum reconstruction (PFPR) is rarely performed during laparoscopic surgery for middle and low rectal cancer patients. This study evaluated the effect of PFPR using barbed wire during laparoscopic surgery on the postoperative defecation function in middle and low rectal cancer patients. METHODS: This was a retrospective study involving a total of 252 middle and low rectal cancer patients who had been subjected to laparoscopic-assisted anterior resection of rectal cancer at Shanghai Changhai Hospital from March 2018 to April 2020. The Wexner and low anterior resection syndrome (LARS) scores were used to evaluate the postoperative defecation function among patients. A Wexner score ≥ 8 and LARS score ≥ 30 were considered to indicate major defecation dysfunction. RESULTS: A total of 229 patients (52 patients subjected to PFPR) were followed up, and the Wexner and LARS scores were recorded. The follow-up rate was 90.87%, the mean follow-up time was 22.88 ± 6.93 months, the stoma rate was 64.29%, the ileostomy reduction surgical rate was 90.74%, and the stoma duration was 7.64 ± 2.94 months. Regarding the assessment of postoperative defecation dysfunction using the Wexner score, a multivariate analysis revealed that a long operation time (odds ratio [OR], 0.991; 95% confidence interval [CI], 0.984-0.999, p = 0.026) and radiotherapy (OR, 0.352; 95% CI, 0.156-0.797, p = 0.012) were independent risk factors for major defecation dysfunction, while a high tumor location (OR, 1.318; 95% CI, 1.151-1.657, p = 0.001) and PFPR (OR, 4.770; 95% CI, 1.435-15.857, p = 0.011) were independent protective factors for major defecation dysfunction. Regarding the assessment of the postoperative defecation function using the LARS score, a multivariate analysis revealed that a high tumor location (OR, 1.293; 95% CI, 1.125-1.486, p < 0.001) and PFPR (OR, 3.010; 95% CI, 1.345-6.738, p = 0.007) were independent protective factors for major defecation dysfunction. A subgroup analysis showed that the postoperative Wexner score (3.13 ± 2.79 vs. 4.71 ± 3.45 p = 0.003) and LARS score (21.77 ± 8.62 vs. 25.14 ± 8.78 p = 0.015) were lower for patients with PFPR than for patients without PFPR. Regarding patients with low rectal cancer, those with PFPR had a lower LARS score than those without it (23.62 ± 8.94 vs. 28.40 ± 7.90, p = 0.022), but there was no significant difference in the Wexner score between the groups. A total of 9.76% of patients with PFPR and 48.89% of those without PFPR showed an intestinal accumulation in the sacral front (p < 0.001). CONCLUSIONS: PFPR and a high tumor location are protective factors for postoperative defecation dysfunction in middle and low rectal cancer patients. PFPR can be routinely performed during laparoscopic surgery.

Enhanced mixing state of black carbon with nitrate in single particles during haze periods in Zhengzhou, China.

Black carbon (BC) plays an important role in air quality and climate change, which is closely associated with its mixing state and chemical compositions. In this work the mixing state of BC-containing single particles was investigated to explore the evolution process of ambient BC particles using a single particle aerosol mass spectrometer (SPAMS) in March 2018 in Zhengzhou, China. The BC-containing particles accounted for 61.4% of total detected ambient single particles and were classified into five types including BC-nitrate (BC-N, 52.3%) as the most abundant species, followed by BC-nitrate-sulfate (BC-NS, 22.4%), BCOC (16.8%), BC-fresh (BC-F, 4.5%) and BC-sulfate particles (BC-S, 4.0%). With enhancement of the ambient nitrate concentration, the relative peak area (RPA) of nitrate in BC-N and BCNS particles both increased, yet only the number fraction (Nf) of BCN particles increased while the Nf of BC-NS particles decreased, suggesting that the enhanced mixing state of BC with nitrate was mainly due to the increase in the ambient nitrate mass concentration. In addition, the Nf of BC-N decreased from 65.3% to 28.4% as the absorbing Ångström exponents (AAE) of eBC increased from 0.75 to 1.45, which indicated the reduction of light absorption ability of aged BC particles with the enhanced formation of BC-N particles. The results of this work indicated a change in the mixing state of BC particles due to the dominance of nitrate in PM2.5, which also influenced the optical properties of aged BC particles.

Overexpression of NDUFV1 alleviates renal damage by improving mitochondrial function in unilateral ureteral obstruction model mice.

Mitochondrial homeostasis plays essential role for the proper functioning of the kidney. NADH-ubiquinone oxidoreductase core subunit V1 (NDUFV1) is an enzyme in the complex I of electron transport chain (ETC) in mitochondria. In the present study, we examined the effects of NDUFV1 on renal function in unilateral ureteral obstruction (UUO) model mice. Our data showed that increased expression of NDUFV1 improves kidney function as evidenced by the decreases in blood urea nitrogen and serum creatinine in UUO mice. Moreover, NDUFV1 also maintains renal structures and alleviates renal fibrosis induced by UUO surgery. Mechanistically, NDUFV1 mitigates the increased oxidative stress in the kidney in UUO model mice. Meanwhile, increased expression of NDUFV1 in the kidney improves the integrity of the complex I and potentiates the complex I activity. Overall, these results indicate that the ETC complex I plays a beneficial role against renal dysfunction induced by acute kidney injury such as UUO. Therefore, NDUFV1 might be a druggable target for developing agents for dealing with disabled mitochondria-associated renal diseases.

Dual-site electrocatalytic nitrate reduction to ammonia on oxygen vacancy-enriched and Pd-decorated MnO2 nanosheets.

Electrocatalytic nitrate reduction (NRR) represents one promising alternative to the Haber-Bosch process for NH3 production due to the lower reaction energy barrier compared to N2 reduction and the potential recycling of nitrogen source from nitrate wastewater. The metal oxides with oxygen vacancy (Ov) display high NH3 selectivities in NRR (NO2-/N2 as side products), but the complexity in Ov enrichment and the inferior hydrogen adsorption on oxides make NRR an inefficient process. Herein, one superior dual-site NRR electrocatalyst that is composed of Ov-enriched MnO2 nanosheets (MnO2-Ov) and Pd nanoparticles (deposited on MnO2) is constructed over the three-dimensional porous nickel foam (Pd-MnO2-Ov/Ni foam). In a continuous-flow reaction cell, this electrode delivers a NO3--N conversion rate of 642 mg N m-2electrode h-1 and a NH3 selectivity of 87.64% at -0.85 V vs. Ag/AgCl when feeding 22.5 mg L-1 of NO3--N (0.875 mL min-1), outperforming the Pd/Ni foam (369 mg N m-2electrode h-1, 85.02%) and MnO2-Ov/Ni foam (118 mg N m-2electrode h-1, 32.25%). Increasing the feeding NO3--N concentration and flow rate to 180.0 mg L-1 and 2.81 mL min-1 can further lift the conversion rate to 1933 and 1171 mg N m-2electrode h-1, respectively. The combination of experimental characterizations and theoretical calculations reveal that the MnO2-Ov adsorbs, immobilizes, and activates the NO3- and N-intermediates, while the Pd supplies the Ov sites with sufficient adsorbed hydrogen (H*) for both the NRR and Ov refreshment. Our work presents a good example of utilizing dual-site catalysis in the highly selective conversion of NO3- to NH3 that is important for nitrate pollution abatement, nitrogen resource recycling, as well as sustainable NH3 production.

The enhanced mixing states of oxalate with metals in single particles in Guangzhou, China.

Recently, internal mixing states of oxalate with metals in single particles have been reported from field studies, yet the role of metals in the formation processes of oxalate remains unclear due to the diversity of chemical components and complex atmospheric environment. In this study, the mixing states of oxalate with five metals, including zinc (Zn), copper (Cu), lead (Pb), vanadium (V) and iron (Fe) were investigated in Guangzhou, China. It was found that 55% of oxalate-containing particles were internally mixed with these metals. The number fraction of oxalate in the metal-containing particles ranged from 5.4-26%, which is much higher than that in the total detected particles (4.0%), indicating significant enrichment of oxalate in the metal-containing particles. Enhanced oxalate production was found in the Fe- and V-containing particles based on distinctly higher relative peak area (RPA) ratios of oxalate to its precursors compared to the total particles, possibly due to enhanced aqueous phase reactions in the Fe- and V-containing particles. However, enrichment of oxalate in the Zn-, Pb-, and Cu-containing particles was possibly associated with complexation of gas phase oxalic acid with the metals, as indicated by the small increase in RPA ratios in these particles. On the other hand, the internal mixing of oxalate with metals was found to provide a way of efficient photolysis of oxalate-metal complexes, which led to a decrease in oxalate after sunrise in the metal-containing particles. In this study, the enhanced mixing states of oxalate with metals have revealed the important role of metals in the production and degradation of oxalate, providing insights for the evaluation of metals in the formation processes of organic aerosol in field studies, which is beneficial to the further study of air pollution in metal emission areas.

Endoscopic closure of a postoperative rectal anastomotic leakage with hemoclips: A case report.

INTRODUCTION AND IMPORTANCE: Hemoclips have been used to protect leakage after endoscopic resection of large colorectal polyps or early-staged rectal cancer, or for perforation of the sigmoid colon during colonoscopy. However, endoscopic clips were seldom used to manage anastomotic leakage after low anterior resection of rectal cancer. CASE PRESENTATION: A patient with postoperative anastomotic leakage after low anterior resection for rectal cancer was successfully treated by endoscopic hemoclips under colonoscopic vision after failure of conservative treatment. Postoperative course was uncomplicated and the patient was discharged from the hospital seven days later. CLINICAL DISCUSSION AND CONCLUSION: Endoscopic hemoclips should be considered as an alternative option for the treatment of an anastomotic leakage in cases where conservative treatment has failed. As they are safe and effective for closure, however good bowel preparation and strict inclusion criteria are required.

Optimizing the metal-support interactions at the Pd-polymer carbon nitride Mott-Schottky heterojunction interface for an enhanced electrocatalytic hydrodechlorination reaction.

We reported one novel strategy via band engineering of the semiconductor support to optimize the metal-support interactions at a Mott-Schottky heterojunction interface and enhance the metal's electrocatalytic hydrodechlorination (EHDC) performance. Taking palladium-polymer carbon nitride (Pd/PCN) as a model, the band tuning of PCN by heteroatomic phosphorus (P) doping substantially boosted the EHDC of 2,4-dichlorophenol (2,4-DCP, one typical chlorinated organic pollutants (COPs)) on Pd, and a peak specific activity of 0.172 min-1 cmPd-2 was achieved by Pd/P-PCN-0.25 (0.25 reflected the P content, and denoted the mass ratio of the P source to PCN precursor used in P-PCN synthesis), quadrupling 0.041 min-1 cmPd-2 of Pd/C and outperforming most of the reported catalysts. The mechanism study revealed the P doping in PCN enabled the positive shift of its Fermi level, which weakened the Pd-PCN interactions and alleviated the electron excess of Pd in Pd/PCN. The P-PCN in Pd/P-PCN-0.25 with the ideal band structure evoked a Pd electronic state that maximized EHDC efficiency. Further investigation into the intermediate products of EHDC on Pd/P-PCN and the biological safety of the 2,4-DCP-contaminated water after EHDC treatment demonstrated the EHDC over our catalyst was environmental-benignity for COPs abatement.

Review of Denonvilliers' fascia: the controversies and consensuses.

The Denonvilliers' fascia (DVF) plays an important role in rectal surgery because of its anatomic position and its relationship to the surrounding organs. It affects the surgical plane anterior to the rectum in the procedure of total mesorectal excision (TME). Anatomical and embryological studies have helped us to understand this structure to some extent, but many controversies remain. In terms of its embryonical origin, there are three mainstream hypotheses: peritoneal fusion of the embryonic cul-de-sac, condensation of embryonic mesenchyme, and mechanical pressure. Regarding its architecture, the DVF may be a single, two, or multiple layers, or a composite single-layer structure. In women, most authors deem that this structure does exist but they are willing to call it the rectovaginal septum rather than the DVF. Operating behind the DVF is supported by most surgeons. This article will review those mainstream studies and opinions on the DVF and combine them with what we have observed during surgery to discuss those controversies and consensuses mentioned above. We hope this review may help young colorectal surgeons to have a better understanding of the DVF and provide a platform from which to guide future scientific research.