Experimental Study on Flame Chemical Composition of Coal and Ammonia Gas-Solid Jet in Flat Flame Burner

Ammonia as a fuel to partially or completely replace fossil fuels is one of the effective ways to reduce carbon dioxide, and the research on ammonia coal cocombustion is of great significance. The combustion characteristics of ammonia are very different from those of pulverized coal, resulting in the ignition and emission characteristics of ammonia and pulverized coal gas flow that is different from traditional pulverized coal flame. In this paper, the effect of pulverized coal concentration in coal and ammonia mixed combustion jet on the ignition distance and gas-phase components at different positions of the jet flame were studied experimentally on the flat flame burner, and the conditions of ignition and ignition stability of coal and ammonia gas-solid fuel were expounded. It was found that the ammonia mixed with pulverized coal changed the temperature field of the flat flame burner and therefore the ignition characteristics of the jet were changed. The ignition delay time at the same jet speed was positively correlated with the pulverized coal concentration, but when the pulverized coal concentration continued to decrease, the influence on the ignition delay time gradually became smaller. The composition of coal ammonia gas-solid fuel changed the heat transfer path and share during combustion, and finally, the flame temperature was negatively correlated with the concentration of pulverized coal. Therefore, the reduction of the pulverized coal concentration was conducive to the stable combustion of coal ammonia mixed fuel. When HAB = 100 mm, the conversion rate of fuel N to NOx per unit mass of coal ammonia mixture increased with the increase of pulverized coal concentration. The NOx production amount first increased and then decreased with the increase of pulverized coal concentration, and the amount of N2O and NO2 decreased rapidly with the increase of HAB. The proportion of NOx in NO exceeded 94%, which was conducive to achieving low nitrogen combustion of coal and ammonia gas-solid fuel. In general, the O2 concentration in the ammonia coal jet flame decreased, the flue gas temperature, and NOx and CO generation increased after mixing ammonia, and the optimal pulverized coal concentration in this experiment was 0.41 kgc/kga (mass ratio of pulverized coal to the sum of N2 and NH3).

Interpretable Machine Learning for Predicting Symptomatic Pneumonitis in Locally Advanced Non-Small Cell Lung Cancer Patients Treated with Concurrent Chemoradiotherapy and Immune Checkpoint Inhibitor Consolidation

PURPOSE/OBJECTIVE(S)

The rate of grade 2 and higher pneumonitis has increased with the use of immune checkpoint inhibitors (ICI) following chemoradiotherapy (CRT) for lung cancer, which may alter previously established dose-volume constraints (DVC). In this study, we used an interpretable machine learning model with clinical and dosimetric features to predict grade 2+ pneumonitis and determine DVC associated with pneumonitis for locally advanced non-small cell lung cancer (LA-NSCLC) radiotherapy (RT).

MATERIALS/METHODS

Between October 2017 and December 2021, 223 consecutively treated patients with LANSCLC treated with CRT and ICI were retrospectively reviewed. The dataset was split into training and test sets (n = 144/79). Clinical features included age, sex, smoking status, pack-years, BMI, ECOG PS, COPD, tumor location, delivered dose, RT technique, chemotherapy agent and volume of GTVp/GTVn. A total of 228 dosimetric features from the heart, contralateral/ipsilateral lung and lungs-IGTV were extracted, including the minimum/mean dose to the hottest x% volume (Dx%[Gy]/MOHx%[Gy]; x was 5-95 in 5% increments) and minimum/mean/maximum dose and percent volume receiving at least xGy (VxGy [%]; x was 5-60 in 5Gy increments), as well as the overlapping volume of each structure with PTV and the distance from each structure to GTVp/GTVn. Feature selection was performed using Boruta, followed by collinearity removal based on the variance inflation factor. The explainable boosting machine (EBM) was trained on the selected features. The performance of EBM on the test set was evaluated using the area under the receiver operating characteristic curve (AUC) and compared with that of blackbox (BB) models, including extreme gradient boosting (XGB), random forest (RF), and supporting vector machine (SVM). The global explanation of each feature's contribution to the predictions provided by the EBM was used to determine DVC. Shapley additive explanations (SHAP) were used to explain BB predictions.

RESULTS

Selected features, ranked in order of EBM's overall feature importance, were V25Gy [%] and MOH65%[Gy] in the ipsilateral lung, the maximum dose in the heart, MOH30%[Gy] in the contralateral lung, and BMI. No dosimetric features in the lungs-IGTV were selected. The SHAP values of three BB models showed similar trends to the feature importance of the EBM. The global explanations of the EBM suggested that to mitigate the risk of pneumonitis, the ipsilateral lung should have V25Gy [%] < 36.8% and MOH65%[Gy] < 39.5Gy, and the heart should have D0.03cc [Gy] < 66.0Gy. Furthermore, an increased risk of pneumonitis was indicated with an increase in BMI, and, surprisingly, a decrease in MOH30%[Gy] in the contralateral lung. The EBM showed the best performance for predicting grade 2+ pneumonitis (AUC = 0.739), followed by RF, SVM, and XGB (AUC = 0.735, 0.733, and 0.717).

CONCLUSION

EBM has the potential to predict grade 2+ pneumonitis in LA-NSCLC patients treated with CRT and ICI, while providing guidance on DVC.

Association of Cardiac Dose with Cardiac Events and Survival for Locally Advanced Non-Small Cell Lung Cancer (LA-NSCLC) Treated with Concurrent Chemoradiotherapy (cCRT) in the Era of Immune Checkpoint Inhibitor (ICI) Consolidation

PURPOSE/OBJECTIVE(S)

To assess the association of cardiac dose with post-cCRT cardiac events and survival among patients (pts) with LA-NSCLC after adoption of ICI consolidation, modern radiotherapy (RT) techniques, and data-driven cardiac constraints.

MATERIALS/METHODS

This single-institution, multi-site retrospective study included 335 pts with LA-NSCLC treated with definitive cCRT (60-70 Gy) from October 2017 to December 2021. Pts were evaluated for ICI consolidation. Cardiac dose constraints included heart volume receiving ≥50 Gy (V50) <25% and mean heart dose (MHD) <20 Gy. Heart, left anterior descending artery (LAD), and left ventricle were autocontoured, manually reviewed, and edited. 21 dosimetric parameters (mean dose, max dose, and min dose to the hottest x% volume [Dx%(Gy); x from 5-95 in 5% intervals]) for each were extracted, as well as LAD V15. Baseline cardiovascular disease (bCVD) was defined as heart failure (HF), coronary artery disease, peripheral vascular disease, or cerebrovascular disease. Primary endpoint was post-cCRT major adverse cardiac events (MACE), defined as acute coronary syndrome, HF hospitalization/urgent visit, coronary revascularization, or cardiac death. Secondary endpoints were grade ≥3 cardiac events (CTCAE v5.0), overall survival (OS), cancer specific mortality (CSM), and other cause mortality (OCM). Competing risk regression was used for MACE and grade ≥3 cardiac events, and Cox regression for OS, CSM, and OCM.

RESULTS

Median age was 68 years, 139 (41%) had bCVD, and 225 (67%) received consolidation ICI. Proton therapy was used in 117 (35%), intensity-modulated RT in 199 (59%), and 3D conformal RT in 19 (6%). Median MHD was 8.7 Gy (IQR 4.6-14.4) and median LAD V15 1.4% (IQR 0-22). Median follow-up was 39.5 months. 35 MACE events occurred; 1- and 2-year cumulative incidence (CI) were 4.2% and 9.5%. No cardiac dosimetric parameter associated with MACE after adjusting for bCVD and age (e.g., MHD sHR 0.98/Gy, 95% CI 0.93-1.03, p = 0.43) or within the following 3 subgroups: no bCVD, photon therapy, and ICI consolidation. 87 grade ≥3 cardiac events occurred; 1- and 2- year CI were 12.6% and 20.4%. Heart dose was not associated with grade ≥3 cardiac events after adjusting for bCVD, ECOG, and BMI (e.g., MHD sHR 1.00/Gy, 95% CI 0.97-1.03, p = 0.85) or within the 3 aforesaid subgroups. 183 OS events occurred, including 125 CSM and 58 OCM events. Multiple cardiac dosimetric parameters associated with worse OS on multivariable analysis (e.g., LAD V15 HR 1.01/%, 95% CI 1.00-1.02, p = 0.003), driven by associations with CSM (LAD V15 HR 1.02/%, p<0.001) but not OCM (LAD V15 HR 1.00/%, p = 0.73). Median OS was worse for LAD V15 ≥10% (22.2 vs 35.1 months, p = 0.004).

CONCLUSION

Among pts with LA-NSCLC treated with cCRT after adoption of ICI consolidation, modern RT techniques, and cardiac constraints, post-cCRT cardiac events were common but showed no association with cardiac dose. Cardiac dose associated with OS, driven by an association with CSM and not OCM, which may not reflect cardiac toxicity.

Multitask AI Models for the Joint Prediction of Overall Survival, Progression-Free Survival, and Death without Progression as a Composite Endpoint for LA-NSCLC Patients Treated with Chemoradiotherapy

PURPOSE/OBJECTIVE(S)

Prior methods model the risk of endpoints separately. Herein, we construct a composite AI model that considers multiple endpoints jointly, including overall survival (OS), progression-free survival (PFS), and death without progression (DWP). Our hypothesis is that the composite model potentially improves predictive performance for patients with locally advanced non-small cell lung cancer (LANSCLC) treated with chemoradiotherapy (CRT).

MATERIALS/METHODS

A total of 335 LANSCLC patients treated with definitive CRT, including all evaluable patients accrued from Oct 2017 to Dec 2021, were randomly split into training/test subsets (n = 234/101). Cardio-pulmonary substructures (CPSs) were autocontoured, manually reviewed, and edited if necessary. A total of 1093 non-independent dosimetric parameters were extracted, including GTVp, GTVn, GTV, PTV, esophagus, lungs minus IGTV, left/right lung, 15 CPSs, and the overlapping volume of each OAR with PTV and the distance from each OAR to GTVp/GTVn. Other clinical parameters included age, consolidation immunotherapy (CI), ECOG score, Charlson comorbidity index, coronary heart disease, histology, PD-L1 expression, and clinical stage (AJCC 8). Within training, censored time-to-event data were imputed based on conditional event distributions derived from Kaplan-Meier estimators for casting survival analysis as a regression problem and training neural additive model (NAM) regressors. Features were selected by LASSO regression for a single endpoint (OS, PFS, DWP) and multi-task (MT) LASSO regression for four separate composite endpoints (OS-PFS, OS-DWP, PFS-DWP, OS-PFS-DWP). The performance of MT NAMs in the test set that jointly predicted the composite endpoints was evaluated using the C-index and compared to that of a single task (ST) NAM that predicted each endpoint separately.

RESULTS

The best testing performance in predicting OS and DWP was attained by the MT NAM that jointly predicted all endpoints (c-index = 0.65, 95% CI 0.58-0.71 for OS; c-index = 0.78, 95% CI 0.69-0.87 for DWP). The best model to predict PFS was also MT between PFS and DWP (c-index = 0.59, 95% CI 0.52-0.65). The c-indices of all ST NAMs were less than 0.56. The best MT NAMs significantly outperformed ST NAMs in predicting OS (p = 0.001) and DWP (p = 0.01) except for PFS (p = 0.32). The best MT NAM in predicting OS and DWP included ECOG score, atria-PTV overlap volume, D75% [Gy] to the left atrium (LA), pulmonary arterial volume, histology (adenocarcinoma), D65% [Gy] to the descending aorta (DA), V10 Gy [%] of the LA and CI in order of overall importance. ECOG score consistently ranked as the most important feature for all four MT NAMs. An increase of ECOG score from 0 to 2 indicated a 6-month earlier risk of mortality and DWP. Atria-PTV overlap volume and D65% [Gy] to the DA were included in all four MT NAMs.

CONCLUSION

MT AI models improved outcome prediction in patients with LANSCLC treated with CRT by jointly learning commonalities between the primary and auxiliary endpoints.

Interpretable Machine Learning Models for Severe Esophagitis Prediction in LA-NSCLC Patients Treated with Chemoradiation Therapy

PURPOSE/OBJECTIVE(S)

Radiation esophagitis is a common adverse event that may occur during chemoradiotherapy (CRT) that can adversely affect survival. This study aimed to develop interpretable machine learning (ML) models to predict grade 3 and higher radiation esophagitis in patients receiving definitive CRT therapy for locally advanced non-small cell lung cancer (LA-NSCLC).

MATERIALS/METHODS

A total of 335 patients with LA-NSCLC who received definitive concurrent CRT at a single institution from 2017 to 2021 were retrospectively identified. Patients with esophagitis were identified and graded according to CTCAE v5.0. For each patient, 31 clinical features and 1093 dose-volume histogram (DVH) parameters from 19 structures were collected. The data was then randomly split into training (n = 233) and testing (n = 102) datasets. Feature selection was performed on the training dataset using the minimum redundancy maximum relevance algorithm to find a set of relevant features while controlling for the redundancy within the selected features, which were then followed by the Boruta algorithm to remove unimportant features and make the ML model more accurate. Synthetic minority oversampling technique was used to handle class-imbalanced datasets by generating synthetic samples for the minority class. Four variants of the Generalized Additive Model (GAM), including Explainable Boosting Machine (EBM), neural GAM (NODE-GAM), eXtreme Gradient Boosting (XGB)-GAM, and Spline, were built with selected features. The models' performance in predicting esophagitis was evaluated using the area under the receiver operating characteristic curve (AUC) in the test dataset. Shape plots were used to interpret the models' output and explain the selected features' contribution to the prediction.

RESULTS

NODE-GAM yielded the highest performance (F1 score = 0.57, accuracy = 0.8, and AUC = 0.837), followed by EBM (F1 score = 0.43, accuracy = 0.8, and AUC = 0.7), Spline (F1 score = 0.42, accuracy = 0.74, and AUC = 0.737), and XGB-GAM (F1 score = 0.42, accuracy = 0.76, and AUC = 0.71). Selected features included D95%[Gy], D90%[Gy], D65%[Gy] and V40Gy [%] for the esophagus, V10Gy [%] for the pulmonary artery, and the distance from GTVn to the ascending aorta. The analysis of the selected features indicated that an increased radiation dose delivered to the esophagus and a shorter distance between the ascending aorta and GTVn were associated with a higher risk of developing esophagitis.

CONCLUSION

Our study demonstrates the feasibility of developing interpretable ML models to predict esophagitis in patients with LA-NSCLC patients treated with CRT. NODE-GAM provided the best accuracy while providing insights into the driving dosimetric factors that could be used to guide optimal RT planning.

Proton Beam Therapy (PBT) Versus Intensity-Modulated Radiotherapy (IMRT) for Locally Advanced Non-Small Cell Lung Cancer (LA-NSCLC) in the Era of Immune Checkpoint Inhibitor (ICI) Consolidation: A Retrospective Cohort Study

PURPOSE/OBJECTIVE(S)

Patients (pts) with LA-NSCLC treated with concurrent chemoradiation (cCRT) and ICI consolidation are at high risk for treatment-related toxicities and subsequent hospitalization. We hypothesized that PBT is associated with a reduction in acute unplanned hospitalizations as compared to IMRT in the era of ICI consolidation.

MATERIALS/METHODS

This single institution, multi-site retrospective study included consecutive pts with LA-NSCLC treated with definitive cCRT with either PBT or IMRT from October 2017 to December 2021. Pts were evaluated for consolidative ICI. Primary endpoint was unplanned treatment-related hospitalization within 90 days of first radiation (RT) treatment. Secondary endpoints included grade 3+ pneumonitis, grade 3+ esophagitis, PFS and OS. Logistic regression was used to assess associations with 90-day hospitalization. Competing risk regression was used for grade 3+ pneumonitis and esophagitis, and Cox regression for PFS and OS.

RESULTS

A total of 316 pts were included: 117 (37%) received PBT and 199 (63%) IMRT. Median age was 68.5 yrs; median RT dose 66.6 Gy (IQR 65.9-70.0). PBT group was older (median 71.1 vs 67.2 yrs, p<0.005) and had a higher Charlson comorbidity index (CCI) (median 4 vs 3, p = 0.02). There was no significant difference in ECOG, smoking pack-years, T stage, N stage, target volume size, or receipt of ICI consolidation (66.7% vs 68.3%, p = 0.76). PBT group had lower mean heart dose (5.9 vs 10.8 Gy, p<0.001), LAD V15 (0 vs 6 %, p = 0.001), mean lung dose (14.7 vs 15.7 Gy, p <0.008) and effective dose to immune circulating cells (median 3.7 vs 4.9 Gy, p<0.001) but not mean esophagus dose. PBT was associated with fewer unplanned 90-day hospitalizations (23.9% vs 34.7%); which persisted on multivariable analysis (OR 0.52, 95% CI 0.30-0.90, p = 0.02) after adjusting for CCI, smoking pack-years, T4 tumors and target volume. Reasons for hospitalization in PBT and IMRT groups included progression (1.7% vs 1.5%), definite/probable toxicity from cCRT (11.1% vs 18.6%), possible toxicity from cCRT (7.7% vs 12.6%) or unrelated to cCRT (3.4% vs 2.0%). There was no significant difference between PBT or IMRT groups in G3+ pneumonitis (1-year 6.0% vs 9.1%, p = 0.49), G3+ esophagitis (1-year 6.0% vs 6.5%, p = 0.71), PFS (median 14.4 vs 15.1 months, p = 0.69), or OS (median 34.2 vs 29.4 months, p = 0.41).

CONCLUSION

Among pts with LA-NSCLC treated with cCRT in the era of ICI consolidation, PBT was associated with fewer acute unplanned hospitalizations compared to IMRT. There was no difference in G3+ pneumonitis, G3+ esophagitis, PFS or OS.

Patterns of Failure, Volume of Disease Progression, and Subsequent Ablative Management in Locally Advanced Non-Small Cell Lung Cancer (LA-NSCLC) Treated with Definitive Chemoradiation and Consolidation Immune Checkpoint Inhibitors (ICI)

PURPOSE/OBJECTIVE(S)

For patients (pts) with LA-NSCLC treated with chemoradiation and consolidation ICI (CRT+ICI), the patterns of failure (POF) and volume of disease progression (PD) are not well characterized. The primary objective of this study was to classify POFs, the frequency of low volume relapse (LVR), and identify pts eligible for further ablative therapy.

MATERIALS/METHODS

We retrospectively identified pts with unresectable stage III NSCLC treated with CRT+ICI between October 2017 and December 2021 at a single institution. Site of first failure was classified as locoregional (LRF), distant (DF), or synchronous LRF + DF. Any LRF was subclassified as in field (IFF; PD within 90% isodose line), marginal (MF; within 50% isodose line) or out of field (OOF; outside of 50% isodose line). LVR was defined as < 3 discrete sites of PD in any number or location of organs. Pts with distant LVR were considered to have oligometastatic relapse. Ablative candidates were defined as pts with < 3 discrete sites of PD amenable to further RT or surgery. Cumulative incidence of PD was calculated with death as a competing risk. Progression free survival (PFS) and overall survival (OS) were calculated from the end of RT and assessed via Kaplan Meier. Multivariable Cox modeling was used to assess correlation of pt characteristics and time-to-event outcomes. Logistic regression was used to predict variables associated with LVR.

RESULTS

A total of 229 pts received CRT+ICI. Median follow up was 39 months and 119 pts experienced PD. Median PFS and OS were 18.4 and 34.5 months, respectively. Of pts with PD, 71 (60%) had DF, 28 (24%) had LRF+DF, and 20 (17%) had LRF. Of pts with any LRF, 28 (57%) had IFF, 10 (21%) had MF, and 10 (21%) had OOF. Estimated 1-year cumulative incidence of LRF, DF, and LRF+DF were 9.3% (95% CI 4.5-16), 39% (95% CI 31-48), and 19% (95% CI 12-27), respectively. A total of 63 (53%) pts had LVR. In pts with LVR, 19 (30%) had isolated thoracic relapse and 44 (69%) had oligometastatic relapse. Most oligometastatic disease was intracranial (22 metastases, 44%). Pts with LVR had a longer median OS vs pts with high volume relapse (37.4 vs 15.2 months, p<0.001). At time of PD, 56 (47%) pts were candidates for further ablative therapies. Subsequent anticancer therapies were local therapy alone (35%), local and systemic therapy (16%), systemic therapy alone (36%), or no therapy (13%). On multivariable analysis, LVR (HR 0.39; 95% CI 0.21-0.73, p = 0.003) and longer receipt of ICI (HR 0.96; 95% CI 0.95-0.98; p<0.001) were associated with improved survival while squamous histology (HR 2.26; 95% CI 1.18-4.32; p = 0.039) was associated with worse survival. Longer receipt of ICI was the only variable predictive for the development of LVR (OR 1.03; 95% CI 1.01-1.05; p = 0.004).

CONCLUSION

This is the largest real-world series reporting POF after CRT+ICI for stage III NSCLC. Approximately half of pts experience LVR and are candidates for further ablative therapy. Further data are needed to define optimal treatment strategies for pts with LVR after CRT+ICI.

[Exploration of clinical pathway-oriented optimal management diagnosis and treatment model for rare diseases]

This study takes Cushing's syndrome, a rare disease, as a model, and adopts the path of "Plan, Do, Check, Action" (PDCA) to explore new methods to optimize the clinical path, can improve the quality and efficiency of diagnosis and treatment of rare diseases. After sorting out the problems existing in the previous diagnosis and treatment mode, our team optimizes the path in various ways and establishes a standard operation procedure (SOP) for the new path. In the evaluation of the optimized mode, 55 patients with Cushing's syndrome were admitted to the Department of Endocrinology, Peking Union Medical College Hospital, including 19 males and 36 females, aged (41.8±14.4) years (6-68 years). The pathway group (28 cases) and the control group (27 cases) were divided according to whether they were included in the new path management at the time of admission, and the effect of path optimization was assessed in terms of time, efficacy, safety and cost. The results showed that compared with the control group, the pathway group had a shorter time of hospitalization in the Department of Endocrinology and critical tests, such as blood cortisol rhythm, low-dose dexamethasone inhibition test, and bilateral inferior petrosal sinus sampling (all P<0.05). There was no significant differences in the decrease of total cortisol after operation, the incidence of postoperative complications, and hospitalization expenses (all P>0.05). The optimized path improves the medical efficiency while ensuring medical quality, safety and no increase in cost. This study proposes PDCA path optimization for complex diseases and establishes SOP process, which provides experience in management optimization for the patient-centered and clinical path-oriented diagnosis and treatment mode of rare diseases.

[Preliminary study on the mechanism underlying the ecological isolation of Oncomelania hupensis populations in Changde City]

OBJECTIVE

To investigate ecological isolation between Oncomelania hupensis snail populations in hilly regions and marshland and lake regions in Yuanjiang valley, Changde City, Hunan Province, and to unravel its underlying mechanisms.

METHODS

Taoyuan County, Shimen County, Linli County and Lixian County in Changde City were selected as snail sampling sites in hilly regions, and Lixian County, Jinshi City, West Lake Administration District, Hanshou County and Dingcheng District were selected as snail sampling sites in marshland and lake areas. Cytochrome C oxidase 1 (cox 1) gene was amplified in snail samples and sequenced. The genetic sequences of O. hupensis snails were aligned using the software MEGA 11, and the haplotypes of O. hupensis snails were determined using the software DNASP 5.10.01. The phylogenetic tree was generated using Bayesian inference with the software MrBayes 3.2, and analysis of molecular variance (AMOVA) was performed to analyze the source of genetic divergence and estimate the genetic divergence index (F_ST) among snail populations with the software Arlequin 3.5.2.2. The genetic barrier among 11 O. hupensis snail populations was estimated using the Monmonier algorithm of adegenet toolkit in R package. The settings with "land in winter and water in summer" in the Yuanjian River section were divided into two categories according to the upstream and downstream, and the areas with "land in winter and water in summer" in the upstream and downstream were transformed into raster data, and then loaded into the software Fragstats 4 for analysis of landscape indicators. The trends in changes of digital elevation were extracted from the Yuanjiang River section based on the digital elevation model, and made three-dimensional visualization using the R package.

RESULTS

The mitochondrial cox 1 gene were amplified in 165 O. hupensis snais from 11 sampling sites and sequenced, and a total of 152 valid gene sequences were obtained, with 46 haplotypes or 9 populations determined. No haplotype was shared in snails between Taoyuan County and Dingcheng District and Hanshou County along the downstream of the Yuanjiang River. The total area of settings with "land in winter and water in summer" was 617.66 hm² in the upsteram of the Yuanjiang River, which consisted of 473 patches, with each patch measuring 1.31 hm², the largest area index of 0.735 2, the landscape division index of 0.999 9, and the landscape shape index of 45.293 7. The total area of settings with "land in winter and water in summer" was 9 956.92 hm² in the downstream of the Yuanjiang River, which consisted of 771 patches, with each patch measuring 12.91 hm², the largest area index of 97.839 9, the landscape division index of 0.042 7, and the landscape shape index of 7.249 6. The area of settings with "land in winter and water in summer" was much larger in the downstream than that in the upstream of the Yuanjiang River, and the stronger landscape connectivity and non-remarkable alteration of riverbed elevation provided suitable habitats for snail breeding.

CONCLUSIONS

The hydrological and environmental characteristics of the upstream of the Yuanjiang River restrain the breeding and spread of O. hupensis, resulting in ecological isolation between Oncomelania hupensis in Taoyuan County and those in the downstream of Yuanjiang River.

A study on serum pro-neurotensin (PNT), furin, and zinc alpha-2-glycoprotein (ZAG) levels in patients with acromegaly

PURPOSE

Acromegaly caused by growth hormone cell adenoma is commonly associated with abnormal glucolipid metabolism, which may result from changes in adipocytokine secretion. This study aims to investigate serum adipokine levels, including pro-neurotensin (PNT), furin, and zinc alpha-2-glycoprotein (ZAG), in acromegalic patients and the correlation between the levels of these three adipokines and GH levels and glucolipid metabolism indices.

METHODS

Sixty-eight acromegalic patients and 121 controls were included, and their clinical data were recorded from electronic medical record system. Serum PNT, furin and ZAG levels were measured by ELISA.

RESULTS

Serum PNT levels in acromegalic patients were significantly higher than controls (66.60 ± 12.36 vs. 46.68 ± 20.54 pg/ml, P < 0.001), and acromegaly was an independent influencing factor of PNT levels (P < 0.001). Moreover, subjects with the highest tertile of PNT levels had a close correlation with acromegaly (OR = 22.200, 95% CI 7.156 ~ 68.875, P < 0.001), even in Model 1 adjusted for gender and age and Model 2 adjusted for gender, age and BMI. Additionally, serum PNT levels were positively correlated with BMI (r = 0.220, P = 0.002) and triglycerides (TGs, r = 0.295, P < 0.001), and TGs were an independent influencing factor of serum PNT levels in acromegalic subjects (P < 0.001). Furthermore, serum PNT levels in obese acromegalic patients were significantly higher than those with normal BMI (P < 0.05). However, serum furin levels were lower in acromegalic patients than controls (0.184 ± 0.036 vs. 0.204 ± 0.061 ng/ml, P < 0.001).

CONCLUSION

This study is the first to demonstrate that acromegalic patients have increased serum PNT levels. Moreover, serum PNT plays a potential role in abnormal lipid metabolism of acromegalic patients.

Bone microarchitecture impairment in prolactinoma patients assessed by HR-pQCT

PURPOSE

Prolactinoma may reduce bone mineral density (BMD) and increase fracture risk, but its influence on bone microarchitecture remains to be elucidated. The purpose of this study is to evaluate bone microarchitecture parameters by high-resolution peripheral quantitative computed tomography (HR-pQCT) in prolactinoma patients.

METHODS

31 prolactinoma patients and 62 age- and sex-matched healthy controls in our center were included, and HR-pQCT was used to evaluate their bone microarchitecture at the radius and tibia. Z-scores for bone microarchitecture parameters were calculated based on previously published reference.

RESULTS

After adjusting for height and weight, prolactinoma patients had lower trabecular (- 0.011 mm, p = 0.005) and cortical thickness (- 0.116 mm, p = 0.008) and cortical area (- 6.0 mm2, p = 0.013) at radius, as well as lower trabecular (- 0.014 mm, p = 0.008) and cortical (- 0.122 mm, p = 0.022) thickness at tibia compared with the controls. Patients with higher prolactin level had more severe bone microarchitecture impairments. After adjusting for prolactin level and age, male patients had lower trabecular volumetric BMD (vBMD), trabecular number, trabecular thickness, and cortical porosity at radius, as well as lower trabecular vBMD, trabecular bone volume fraction, trabecular number, and cortical area, and higher trabecular separation at tibia compared with female patients. Z-score for radius vBMD was correlated with Z-score for areal BMD (aBMD) at lumbar and femoral neck, while Z-score for tibia vBMD was correlated with Z-score for lumbar aBMD, and some patients with vBMD Z-score below - 2.0 had aBMD Z-score within normal range.

CONCLUSION

Peripheral bone microarchitecture was impaired in prolactinoma patients, especially in patients with higher prolactin level. We compared the bone microarchitecture of prolactinoma patients and healthy controls by high-resolution peripheral quantitative computed tomography (HR-pQCT), and found that many bone microarchitecture parameters were impaired among prolactinoma patients. Such impairment was more prominent among patients with higher prolactin level.

[Research progress of circumferential tracheal reconstruction via tissue-engineered trachea]

Tissue engineering, as a new technology, provides a new avenue for the reconstruction of circumferential tracheal defects, which has always been a tremendous challenge for surgeons around the world. Recently, technologies such as decellularization, 3-dimensional printing, electrospinning and cell sheet have significantly enhanced the chondrification. Implantation of epithelial cells or transplantation of epithelial cell sheets also has accelerated the process of epithelialization. And pedicle muscle flap proved to be a reliable strategy for vascularization of tissue-engineered trachea. But it is still a huge challenge to achieve circumferential tracheal functional reconstruction. The key difficulty lies in how to simultaneously realize the functional regeneration of cartilage, blood vessels and epithelial tissues of tissue-engineered trachea. Therefore, how to integrate the above schemes and finally realize segmental tracheal reconstruction needs further research. This article reviews the research progress of repairing circumferential tracheal defects based on tissue engineering technology.

Direct Conversion of Solid g-C3N4 into Metal-ended N-doped Carbon Nanotubes for Rechargeable Zn-Air Batteries

Developing low-cost and bifunctional electrocatalysts with activity for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is great desirable for metal-air battery. Herein, we demonstrate an approach to realize...

Epoxide activation by a silver phosphonate for heterogeneous catalysis of CO2 cycloaddition

Hydrothermal reaction of silver nitrate and a tetraphosphonic acid (H8L) affords a novel coordination polymer, with the general formula, [Ag10(H3L)2(H2O)2(4,4’-bipy), namely compound 1. It is built from extend …Ag-O-P-O… chains...

Identification of the metabolic signatures of prostate cancer by mass spectrometry-based plasma and urine metabolomics analysis

OBJECTIVE

Prostate cancer (PCa) is one of the most commonly diagnosed cancers among men which is associated with profound metabolic changes. Systematic analysis of the metabolic alterations and identification of new biomarkers may benefit PCa diagnosis and a deep understanding of the pathological mechanism. The purpose of this study was to determine the metabolic features of PCa.

METHODS

Plasma and urine metabolites from 89 prostate cancer (PCa) patients, 84 benign prostatic hyperplasia (BPH) patients, and 70 healthy males were analyzed using LC-MS/MS and GC-MS. The Orthogonalised Partial Least Squares Discriminant Analysis (OPLS-DA) was used to find the significantly changed metabolites. The clinical value of the candidate markers was examined by receiver operating characteristic curve analysis and compared with prostate-specific antigen (PSA).

RESULTS

Multivariate statistical analyses found a series of altered metabolites, which related to the urea cycle, tricarboxylic acid cycle (TCA), fatty acid metabolism, and the glycine cleavage system. Plasma Glu/Gln showed the highest predictive value (AUC = 0.984) when differentiating PCa patients from healthy controls, with a higher sensitivity than PSA (96.6% vs. 94.4%). Both Glu/Gln and PSA displayed a low specificity when differentiating PCa patients from BPH patients (<53.2%), while the combination of Glu/Gln and PSA can further increase the diagnostic specificity to 66.9%.

CONCLUSIONS

The present study showed the metabolic features of PCa, provided strong evidence that the amide nitrogen and the energy metabolic pathways could be a valuable source of markers for PCa. Several candidate markers identified in this study were clinically valuable for further assessment.

[Effects of orlistat and metformin on metabolism and gonadal function in overweight or obese patients with polycystic ovary syndrome]

The aim of this study was to assess the effects of orlistat or metformin treatment on lipid and glucose metabolism, and gonadal function in obese/overweight women with polycystic ovary syndrome (PCOS). A total of 39 patients diagnosed with PCOS were randomly (digital table method) divided into orlistat treatment group (20 cases) and metformin treatment group (19 cases). Compared with those before, treatment with either orlistat or metformin significantly reduced body weight, body mass index (BMI), hip circumferences, and serum insulin levels of the PCOS patients both at the end of 3 months and 6 months (P<0.05). No significant differences could be viewed between orlistat and metformin treated subjects. Moreover, orlistat treatment significantly lowered the levels of low-density lipoprotein cholesterol, total cholesterol, fasting blood glucose, and homeostasis model assessment-insulin resistance (HOMA-IR) (P<0.05), while there were no significant changes in above parameters with metformin treatment. The improvement of menstrual cycle was observed after 6-month treatment in both groups (P<0.05). However, changes in polycystic ovarian morphology by ultrasound were only observed in orlistat treated group. In conclusion, orlistat is comparable with metformin in weight loss and improvement of insulin resistance and menstrual cycle, and is superior to metformin in improvement of lipid metabolism in overweight/obese PCOS patients.

Novel AVPR2 mutations and clinical characteristics in 28 Chinese families with congenital nephrogenic diabetes insipidus

AIMS

To investigate genotype and phenotype of congenital nephrogenic diabetes insipidus caused by AVPR2 mutations, which is rare and limitedly studied in Chinese population.

METHODS

88 subjects from 28 families with NDI in a department (Beijing, PUMCH) were screened for AVPR2 mutations. Medical records were retrospectively reviewed and characterized. Genotype and phenotype analysis was performed.

RESULTS

23 AVPR2 mutations were identified, including six novel mutations (p.Y117D, p.W208R, p.L313R, p.S127del, p.V162Sfs*30 and p.G251Pfs*96). The onset-age ranged from 1 week to 3 years. Common presentations were polydipsia and polyuria (100%) and intermittent fever (57%). 21% and 14% of patients had short stature and mental impairment. Urine SG and osmolality were decreased, while serum osmolality and sodium were high. Urological ultrasonography results showed hydronephrosis of the kidney (52%), dilation of the ureter (48%), and thickened bladder wall or increased residual urine (32%), led to intermittent urethral catheterization (7%), cystostomy (11%) and binary nephrostomy (4%). Urological defects were developed in older patients. Genotype and phenotype analysis revealed patients with non-missense mutations had higher levels of serum sodium than missense mutations.

CONCLUSION

In the first and largest case series of NDI caused by AVPR2 mutations in Chinese population, we established genetic profile and characterized clinical data, reporting six novel mutations. Further, we found genotype was associated with phenotype. This knowledge broadens genotype and phenotype spectrum of rare congenital NDI caused by AVPR2 mutations, and provides basis for studying molecular biology of AVPR2.

[Changes in platelet related parameters in obese patients after sleeve gastrectomy]

To compare changes in platelet related parameters in obese patients before and after sleeve gastrectomy (SG), we retrospectively analyzed the clinical data of 31 obese patients who underwent SG in Peking Union Medical College Hospital from December 2012 to September 2020. Results showed that compared with those before surgery, platelet count (PLT) decreased significantly at 2-12 weeks of follow-up (P=0.009), while platelet distribution width (PDW), mean platelet volume (MPV), and large platelet ratio (P-LCR) increased significantly at the same periods of follow-up after operation (P<0.001). However, the levels of PDW, MPV, and P-LCR began to decrease at 16-55 weeks when compared with those at 2-12 weeks of follow-up (P<0.01). PLT was positively correlated with white blood cells and neutrophils at 2-12 weeks of follow-up and positively correlated with high sensitivity C-reactive protein at 16-55 weeks of follow-up after operation (P<0.05).

Design of Gd3+-immobilized two-dimensional magnetic magadiite nanosheets for highly selective enrichment of phosphopeptides

Exfoliated magadiite nanosheets embedded with Fe₃O₄ were constructed. Advantage was taken of the strong coordination between the silanol groups in magadiite nanosheets and the Gd³⁺ ion to prepare the final adsorbent, Gd³⁺-immobilized magnetic magadiite nanosheets. The adsorbent with two-dimensional (2D) morphology offered high surface area and abundant Gd³⁺ contents for phosphopeptides enrichment, on which Fe₃O₄ with positive electricity incorporated the magnetic properties. Combining with matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI TOF-MS), the method showed low detection limit (0.05 fmol). The feasibility of using the 2D nanocomposite for phosphopeptides enrichment was demonstrated using mixtures of β-casein and bovine serum albumin (1:5000). The standard deviation of captured phosphopeptides in three repeated experiments were in the range 0.15-0.42 (< 0.5% RSD). Further evaluation revealed that the nanocomposite was capable of enriching phosphopeptides from non-fat milk, human saliva, and serum. A novel Gd³⁺-immobilized two-dimensional magnetic magadiite nanosheets-based enrichment platform was designed. The developed material was employed as the adsorbent for the selective enrichment of phosphopeptides by coupling with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The material was successfully applied to enrich phosphopetides from standard peptide mixtures, nonfat milk, human saliva, and serum.

[Updated key points of Chinese Consensus for the Diagnosis and Treatment of Acromegaly (2021 edition)]

Led by the China Pituitary Adenoma Specialist Council, the Chinese Consensus for the Diagnosis and Treatment of Acromegaly (2021 Edition) is developed combined with the research progress of pituitary growth hormone (GH)-secreting adenoma both at home and abroad, evidence-based evidence of the diagnosis and treatment of acromegaly, and China's national conditions. Based on the guideline for acromegaly (2013 Edition), the new version of consensus emphasizes the importance of multidisciplinary team (MDT) and individual therapy. The criteria for control of acromegaly is discussed. Pathological criteria for the diagnosis of pituitary GH-secreting adenoma is updated. New developments in surgery, drug and radiotherapy are introduced. Meanwhile, the diagnosis and treatment of acromegaly patients concurrent with other particular scenarios, including pregnancy and refractory pituitary GH-secreting adenoma is suggested. This article aims to describe the updated key points of the new version of the consensus, and thus facilitate the clinical implementation of standardized diagnosis and treatment for acromegaly patients.

Strong adsorption, catalysis and lithiophilic modulation of carbon nitride for lithium/sulfur battery

Lithium/sulfur (Li/S) batteries have emerged as one of the most promising next-generation energy storage systems with advantages of high theoretical energy density, low cost and environmental friendliness. However, problems regarding to severe shuttle effect of soluble polysulfide, poor electronic/ionic conductor of solid charged/discharged products (S₈ and Li₂S), and fatal swell of volume along with the growth of Li dendrites greatly deteriorate the sulfur utilization and capacity retention during extended charge-discharge cycles. With advantages of high nitrogen content, lithiophilic modulation and tunable charge density and charge transfer, carbon nitride (g-C₃N₄) has played a positive role in restricting the shuttle effects and dendrite formation. This minireview mainly discusses these research achievements of g-C₃N₄ in Li/S batteries, aiming to provide a basic understanding and direct guidance for further research and development of functionalized g-C₃N₄ materials in electrical energy storage. The two-dimensional (2D) structure of g-C₃N₄ with abundant hierarchical pores improves its accommodation capacity for sulfur by effectively confining the lithium polysulfides (LiPSs) into the pores, and provides favorable channels for ion diffusion. The rich nitrogen and carbon defects further offer more active sites for strongly adsorbing LiPSs and bridge electron transfer pathway at atomic scale for catalytic reactions to accelerate redox kinetics of Li/S conversion chemistry. Moreover, the features of lithiophilic wettability, high adsorption energy and densely distributed lithiophilic N of g-C₃N₄ provide a large number of adhesive sites for lithium cation (Li⁺) and disperse the nucleation sites to enable uniform nucleation and deposition of Li on the anode surface and to suppress formation and growth of Li dendrites. Finally, the g-C₃N₄ also effectively regulates the wettability between Li anode and solid inorganic electrolyte, and reduces the crystallinity of solid polymer electrolyte to enhance the Li⁺ migration ability and ionic conductivity.

Ternary flower-sphere-like MnO2-graphite/reduced graphene oxide nanocomposites for supercapacitor

Chemical fabrication of a nanocomposite structure for electrode materials to regulate the ion diffusion channels and charge transfer resistances and Faradaic active sites is a versatile strategy towards building a high-performance supercapacitor. Here, a new ternary flower-sphere-like nanocomposite MnO₂-graphite (MG)/reduced graphene oxide (RGO) was designed using the RGO as a coating for the MG. MnO₂-graphite (MnO₂-4) was obtained by KMnO₄ oxidizing the pretreated graphite in an acidic medium (pH = 4). The GO coating was finally reduced by the NaBH₄ to prepare the ternary nanocomposite MG. The microstructures and pore sizes were investigated by x-ray diffraction, scanning electron microscopy, thermogravimetric analysis, and nitrogen adsorption/desorption. The electrochemical properties of MG were systematically investigated by the cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance spectroscopy in Na₂SO₄ solution. The MG as an electrode material for supercapacitor exhibits a specific capacitance of 478.2 and 454.6 F g^-1 at a current density of 1.0 and 10.0 A g^-1, respectively. In addition, the capacitance retention was 90% after 8,000 cycles. The ternary nanocomposite enhanced electrochemical performance originates from the specific flower-sphere-like morphology and coating architecture bringing higher specific surface area and lower charge transfer resistance (R_ct).

[Study on the hospitalization cost and its influencing factors of imported malaria patients in Guangxi Zhuang Autonomous Region and Yunnan Province]

OBJECTIVE

To analyze the hospitalization cost and its influencing factors of imported malaria patients in Guangxi Zhuang Autonomous Region and Yunnan Province, so as to provide insights into the evaluation of the economic burden due to imported malaria, and the guiding of malaria control and the rational allocation of medical resources.

METHODS

The data pertaining to the hospitalization costs of imported malaria patients admitted to Shanglin County People's Hospital in Guangxi Zhuang Autonomous Region during the period from January 1 through December 31, 2019, and Tengchong Municipal People's Hospital in Yunnan Province from January 1, 2015 to December 31, 2019, were collected, and the epidemiological data of these imported malaria patients were extracted from the Information Management System for Parasitic Diseases Control and Prevention, China. The composition of the hospitalization expenses was analyzed using a descriptive method. In addition, the factors affecting the hospitalization expenses of imported malaria patients were identified using a univariate analysis and a recursive system model.

RESULTS

A total of 206 imported malaria patients were included in this study, including 194 men (94.17%) and 12 women (5.83%). The mean length of hospital stay was 5.00 days per patient and the median hospitalization expenses were 2 813.07 Yuan per time, in which the expenses for laboratory examinations were the highest (45.31%, 1 274.62/2 813.07). Univariate analysis showed that hospital (z = 5.43, P < 0.01), type of malaria (χ² = 34.86, P < 0.01) and type of payment (χ² = 7.72, P < 0.05) were factors affecting the hospitalization expenses of imported malaria patients. Recursion system modeling revealed that the total effects on hospitalization expenses of imported malaria patients included length of hospital stay (0.78), selection of hospital (0.34), basic medical insurance for urban and rural residents (0.19), new rural cooperative medical care (0.17), Plasmodium falciparum malaria (0.15), gender (0.11) and P. vivax malaria (0.09).

CONCLUSIONS

The hospitalization expenses of imported malaria patients are affected by multiple factors in Guangxi Zhuang Autonomous Region and Yunnan Province, in which the length of hospital stay is the most predominant influencing factor. A reduction in the length of hospital stay is effective to decrease the hospitalization expenses of imported malaria patients.

Photocatalytic selective H2release from formic acid enabled by CO2captured carbon nitride

The selective decomposition of formic acid (FA) traditionally needs to be carried out under high temperature with the noble metal-based catalysts. Meanwhile, it also encounters a separation of H₂and CO₂for pure H₂production. The photocatalytic FA dehydrogenation under mild conditions can meet a growing demand for sustainable H₂generation. Here, we reported a photocatalytic selective H₂release from FA decomposition at low temperature for pure H₂production by Pt/g-C₃N₄. Low-cost and easy-to-obtained urea was utilized to produce carbon nitride as the metal-free semiconductor photocatalyst, along with a photodeposition to obtain Pt/g-C₃N₄. The electrochemical evidences clearly demonstrate the photocatalytic activity of Pt/g-C₃N₄to produce H₂and CO₂in one-step FA decomposition. And, the impedance is the lowest under simulated solar light of 70 mW cm^-2with a faster electron transfer kinetic. Under simulated solar light, H₂production rate is up to 1.59 mmol · h^-1· g^-1for FA with concentration at 2.65 mol l^-1, 1700 000 times larger than that under visible light and 1928 times under ultraviolet (UV) light. DFT calculations further elucidate that nitrogen (N) active site at the g-C₃N₄has an excellent adsorption towards CO₂molecule capture. Then, H₂molecules are selectively released to simultaneously separate H₂and CO₂in solution. Platinum (Pt) at Pt/g-C₃N₄as the catalytic site contributes into the acceleration of H₂production.

Ivy Sign in Moyamoya Disease: A Comparative Study of the FLAIR Vascular Hyperintensity Sign Against Contrast-Enhanced MRI

BACKGROUND AND PURPOSE

The ability of the ivy sign on contrast-enhanced T1-weighted MR imaging (CEMR) to reflect cerebral perfusion and postoperative revascularization in Moyamoya disease remains largely unknown. We aimed to compare the capabilities of CEMR and FLAIR.

MATERIALS AND METHODS

CEMR, FLAIR, arterial spin-labeling, and DSA were performed in 44 patients with Moyamoya disease. The ivy sign was scored separately on CEMR and FLAIR using the Alberta Stroke Program Early CT Score. The status of leptomeningeal collaterals was scored on DSA. The postoperative Matsushima grade was evaluated at least 3 months after surgical revascularization.

RESULTS

Scoring of the ivy sign on CEMR showed excellent interrater reliability, and FLAIR vascular hyperintensity showed moderate interrater reliability. Correlation analyses revealed that DSA scores were more consistent with the CEMR-based ivy sign score (r = 0.25, P = .03) than with FLAIR vascular hyperintensity (r = 0.05, P = .65). The CEMR-based ivy sign score was significantly correlated with CBF in late-Suzuki stage Moyamoya disease (t = -2.64, P = .02). The CEMR-based ivy sign score at baseline was significantly correlated with the postoperative Matsushima grade (r = 0.48, P = .03).

CONCLUSIONS

In this study, CEMR outperformed FLAIR in capturing the ivy sign in Moyamoya disease. In addition, the CEMR-based ivy sign score provided adequate information on hemodynamic status and postoperative neovascularization. The current study suggested that CEMR could be considered as an alternative to FLAIR in future studies investigating leptomeningeal collaterals in Moyamoya disease.

Sulfonate substituted rhodamine hydrophilic fluorescent probes: Application to specific detection of Fe3+ and imaging in living fish

Two Sulfonate substituted rhodamine hydrophilic fluorescent probes RbS1 and RbS2 were designed and synthesized for specific detection of Fe³⁺. It was found that the probe RbS2 was stronger than RbS1 in the water solubility test. Both of them displayed responses to Fe³⁺ with a apparent fluorescence enhancement at 585 nm, accompanied with a distinct fluorescence change to pink. Upon addition of Fe³⁺ ions (0-16 μM), the emission intensity of RbS1 and RbS2 increased to 40 and 70 fold, which exhibited a good linear relationship with the concentration of Fe³⁺. The detection limits of RbS1 and RbS2 for sensing Fe³⁺ were 0.64 μM and 0.56 μM, respectively. The binding ratios of the RbS1 and RbS2 to Fe³⁺ were 1:1 and the recycling ability for Fe³⁺ was reasonable. RbS1 and RbS2 have been successfully applied to the determination of Fe³⁺ in real water samples with satisfactory recovery and accuracy. In further living fish imaging test, the probe RbS2 was distributed into abdomen, which exhibited better fluorescence imaging ability than that of RbS1.

Nitrogen and oxygen tailoring of a solid carbon active site for two-electron selectivity electrocatalysis

The second nearest C atoms of pyridinic N were predicted to be an active site for 2e⁻ ORR using DFT calculations, and were experimentally demonstrated to possess a tailoring function of a pyridinic N structure and O dopants on carbon materials.

Association of Frailty Status with Risk of Fall among Middle-Aged and Older Adults in China: A Nationally Representative Cohort Study

OBJECTIVES

To investigate the association between frailty status and risk of fall among middle-aged and older Chinese people.

DESIGN

A nationally representative prospective cohort study.

SETTING AND PARTICIPANTS

The study included 13,877 community-dwelling participants aged 45 years and above from the China Health and Retirement Longitudinal Study.

METHODS

Frailty status was identified by the frailty index of health deficit accumulation. 34 variables at baseline were selected to calculate the frailty index. We excluded participants with incomplete information in construction of the frailty index at baseline. Falls were measured based on the respondents' self-report. We used a logistic regression model to estimate the associations between the frailty status and risk of fall, and subgroup analyses and sensitivity analyses were further conducted.

RESULTS

Of 13,877 participants, 2310 (16.6%) had falls during the observation period. 9027 (65.0%) participants were classified as robust, 4019 (29.0%) participants were classified as pre-frail, and 831 (6.0%) participants were classified as frail. Our results indicated per 0.01 increment in the frailty index was significantly associated with an increased risk of fall among middle-aged and older participants (OR: 1.52, 95%CI: 1.45-1.60). Such association was stronger when frailty was presented as a categorical variable, with an OR of 1.75 (95%CI: 1.59-1.93) for pre-frail and 3.04 (95%CI: 2.60-3.56) for frail. The area under the curve of the logistic model was 0.612 (95%CI: 0.600-0.625). Each 0.01 increment of the frailty index was association with a higher risk of fall among middle-aged (45-59years) participants (OR: 1.44, 95%CI: 1.29-1.60) than among older (≥60 years) participants (OR: 1.28, 95%CI: 1.16-1.41) at baseline (p=0.015 for interaction).

CONCLUSION

Frailty was significantly associated with an increased risk of fall among community-dwelling middle-aged and older people in China. It is necessary to screen and recognize frailty status to prevent falls among middle-aged and older adults.

Visible-light photocatalytic selective oxidation of C(sp3)–H bonds by anion–cation dual-metal-site nanoscale localized carbon nitride

Anion–cation dual-metal-site nanoscale localized carbon nitride exhibits a significantly enhanced photocatalytic activity for the oxidation of alkanes and alcohols with a high activity and a wide functional group tolerance.

Triggers of stress cardiomyopathy and their association with clinical outcomes

Background

Stress cardiomyopathy can be a result of physical stress, emotional stress, or both. Whether the type of trigger affects clinical outcomes is not well studied.

Purpose

The objectives of this study were to identify the prevalence of emotional and physical stressors and to assess differences in patient characteristics and mortality based on the type of trigger.

Methods

We conducted a retrospective review of 523 consecutive patients who presented to our institution from 2006 to 2016. All patients presented with acute coronary syndrome. Triggers for stress cardiomyopathy were abstracted from reviewing patients' medical records. Patients were categorized into those with 1) physical trigger, 2) emotional trigger, 3) both physical and emotional trigger, or 4) no known trigger. Baseline characteristics and clinical outcomes were reported.

Results

Among 523 patients with stress cardiomyopathy, 151 (28.9%) had a physical trigger, 189 (36.1%) had an emotional trigger, 30 (5.7%) had both physical and emotional triggers, and 153 (29.3%) had no known triggers identified. Men comprised the higher proportion of patients with physical triggers. Comorbidities including diabetes, pulmonary disease, chronic kidney disease and hypothyroidism were more prevalent among patients with physical triggers. Compared to patients with no obvious triggers, patients with a physical trigger had a much higher mortality rate (hazard ratio 2.0, 95% CI 1.2–3.3, p=0.007), whereas patients with an emotional trigger had significantly lower mortality (hazard ratio 0.40, 95% CI 0.21–0.89, p=0.007).

Conclusion

Different triggers for stress cardiomyopathy is associated with different baseline characteristics and clinical outcomes. Overall survival is worst in the group with an identified physical trigger.

Figure 1

Funding Acknowledgement

Type of funding source: None

Heterogeneous photocatalytic anaerobic oxidation of alcohols to ketones by Pt-mediated hole oxidation

We report a platinum nanocluster/graphitic carbon nitride (Pt/g-C₃N₄) composite solid catalyst with a photocatalytic anaerobic oxidation function for highly active and selective transformation of alcohols to ketones. The desirable products were successfully obtained in good to excellent yields from various functionalized alcohols at room temperature, including unactivated alcohols. Mechanistic studies indicated that the reaction could proceed through a Pt-mediated hole oxidation initiating an α-alcohol radical intermediate followed by a two-electron oxidation pathway. The merit of this strategy offers a general approach towards green and sustainable organic synthetic chemistry.

CircHIPK3 Facilitates the G2/M Transition in Prostate Cancer Cells by Sponging miR-338-3p

Background

Circular RNAs (circRNAs) play a crucial role in gene expression regulation. CircHIPK3 is a circRNA derived from Exon 2 of HIPK3 gene and its role in prostate cancer (PCa) is still unclear.

Methods

CCK8 assays, flow cytometry and colony formation assays were performed to assess the effects of circHIPK3 in PCa cells. Bioinformatics analysis, RNA pull-down assay, RNA immunoprecipitation assay (RIP), and luciferase activity assay were performed to dissect the mechanism underlying circHIPK3-mediated G2/M transition in PCa cells.

Results

CircHIPK3 expression was upregulated in PCa cells and prostate cancer tissues. Overexpression of circHIPK3 or circHIPK3 silencing altered PCa viability, proliferation and apoptosis in vitro. CircHIPK3 could sponge miR-338-3p and inhibit its activity, resulting in increased expression of Cdc25B and Cdc2 in vitro.

Conclusion

CircHIPK3 promotes G2/M transition and induces PCa cell proliferation by sponging miR-338-3p and increasing the expression of Cdc25B and Cdc2. CircHIPK3 may play an oncogenic role in PCa.

pH-Zone-refining counter-current chromatography for two new lipo-alkaloids separated from refined alkaline extraction of Kusnezoff monkshood root

An efficient and refined method for the separation of six aconitine‐type alkaloids from the alkaline prepared “Kusnezoff monkshood root” was established. It is the first study that two new lipo‐alkaloids were successfully isolated from refined sample by pH‐zone‐refining counter‐current chromatography rather than synthetic method. It was of interest that a great deal of lipo‐alkaloids was produced in crude extract from the alkalization of “Kusnezoff monkshood root.” A refined sample method was proposed to enrich two types of alkaloids by liquid–liquid extraction, i.e. lipo‐alkaloids and monoester‐diterpenoid alkaloids. The pH‐zone‐refining counter‐current chromatography was performed with an optimized two‐phase solvent system composed of n‐hexane‐ethyl acetate–methanol–water (3:5:4:5, v/v), where upper organic phase was added to 3 mmol/L triethylamine as a retainer and lower aqueous mobile phase was added to 3 mmol/L hydrochloric acid as an eluter. As a result, six aconitum alkaloids, including two lipo‐alkaloids (8‐lino‐14‐benzoylaconine, 8‐pal‐14‐benzoylaconine), three monoester‐diterpenoid alkaloids (14‐benzoylmesaconine, 14‐benzoylaconine, beyzoyldeoxyaconine), and one aconine alkaloid (neoline) were acquired from the plant at the same time. The anti‐inflammatory activities of the two new lipo‐alkaloids were compared to the six alkaloids in vitro, in cyclo‐oxygen‐ase‐2 inhibition assays. The separation mechanism of six alkaloids by pH‐zone‐refining counter‐current chromatography was illustrated.

[Etiology and clinical features of primary adrenal insufficiency]

Objective: To summarize the etiology of primary adrenal insufficiency (PAI) and analyze its clinical features. Methods: A retrospective analysis was performed in the Department of Endocrinology, Peking Union Medical College Hospital from October 1981 to June 2019. Patients with PAI as the first symptom were enrolled. The etiology of PAI was analyzed and the clinical characteristics was also summarized. Results: A total of 131 patients with PAI were enrolled, including 87 males and 44 females (57 adolescents, and 74 adults). The age ranged from 0 to 73 years. The primary cause of PAI in adolescents was genetic defects (52.6%, 30/57), in which congenital adrenal dysplasia caused by DAX1 gene deficiency accounted for 50.0% (15/30), followed by autoimmunity (22.8%, 13/57). The primary cause of adult PAI was infection (58.1%, 43/74), of which tuberculosis accounted for the majority (93.0%, 40/43), and autoimmune adrenalitis accounted for 19.0% (14/74). Compared with the tuberculosis group, female patients were more common, and the onset age was younger, the plasma cortisol, serum sodium, fasting blood glucose, creatinine and aldosterone were lower (all P<0.05), and serum potassium and renin levels were higher in the autoimmune adrenalitis group (both P<0.05). Conclusions: In the current study, the proportion of PAI caused by infection in the adult group was higher than that in the adolescent group. The most common cause of adult PAI was tuberculosis infection. The most common cause of childhood PAI was genetic defects. Autoimmune damage to the adrenal glands may be more severe than tuberculosis infection.

Inhibitor 9 Combined With Androgen Deprivation Therapy or Chemotherapy Delays the Malignant Behavior of Castration-Resistant Prostate Cancer Through K-Ras/PLCε/PKCε Signaling Pathway

Castration-resistant prostate cancer (CRPC) is a progressed stage of prostate cancer, which requires better understanding of the mechanisms and remains an unmet clinical need. As a common oncogene, K-Ras is associated with malignant behavior in different types of tumors but its role in CRPC is unknown. The present study aims to find the mechanism of K-Ras in CRPC and whether it can be used as a crucial molecule for the treatment of CRPC. For this purpose, tissue samples from primary prostate cancer (PPC) and CRPC patients were analyzed by immunohistochemistry and the data showed that K-Ras was elevated in CRPC. More importantly, higher K-Ras expression was related to a shorter recurrence-free survival time in patients with CRPC. In addition, K-Ras promoted the invasion, migration, and drug resistance of CRPC cells by activation of PLCε/PKCε signaling pathway. Meanwhile, the inhibitor of K-RasG12C mutants was able to inhibit malignant behavior of CRPC cells in vitro and in vivo. Inhibitors of K-RasG12C mutants have entered clinical trials. Taken together, the study shows that K-Ras may activate PKCε through PLCε, resulting in the alterations of malignant behavior of CRPC. Inhibitor 9, an inhibitor of the K-RasG12C mutant, has a strong anti-tumor effect in CRPC, which potentially suggests that inhibitors of this nature may serve as a promising treatment for CRPC.

KLF8 promotes cancer stem cell-like phenotypes in osteosarcoma through miR-429-SOX2 signaling

Krüppel-like factor 8 (KLF8) regulates critical gene transcription associated with different types of cancer. A novel paradigm in tumor biology suggests that the initiation and progression of osteosarcoma (OS) are driven by osteosarcoma stem cell-like cells (OSCs), but the role and underlying mechanisms of KLF8 in OSCs are poorly elucidated. In this study, an obviously increased level of KLF8 is shown in 9 out of 10 primary OS tissues and is associated with the poor progression-free interval. Significantly, KLF8 expression in CD133+ OSCs is higher than that in CD133- counterparts. By knocking down KLF8 in CD133+ OSCs, we show that si-KLF8-OSCs can hardly form compact spheres. In the meantime, infection with si-KLF8 in CD133+ OSCs results in the downregulation of OCT4 and SOX2; increased adriamycin (ADM) sensitivity; and decreased tumorigenic potential in vivo. Mechanisms study demonstrates that KLF8 directly binds the miR-429 promoter region and regulates its expression transcriptionally. Furthermore, we indicate that miR-429 directly targets SOX2 to mediate cancer stem cell-like features in CD133+ OSCs. In the clinic, miR-429 levels are negatively associated with KLF8 levels in OS, suggesting that an elevated KLF8/miR-429 ratio may have clinical value as a predictive biomarker. In conclusion, targeting the KLF8-miR-429-SOX2 signaling pathway may provide an effective therapeutic approach to suppress the initiation and progression of OS.

Electro-synthesized Co(OH)2@CoSe with Co-OH active sites for overall water splitting electrocatalysis

Constructing noble metal-free electrocatalytically active sites for the simultaneous hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline solution is key to realizing electricity-driven water splitting in practical applications. Here, we rationally designed Co(OH)₂@CoSe nanorods (NRs) as an excellent bifunctional electrocatalyst by an in situ electrochemical transformation strategy, where the Co-based nanorod template was converted into Co(OH)₂@CoSe at the cathode. The obtained electrode exhibits superior electrocatalytic activity for both the HER (overpotential of 208 mV at 20 mA cm^-2) and the OER (268 mV at 20 mA cm^-2) at high current density in a 1 M KOH solution. The theoretical calculations and experimental evidence indicate that the chemical coupling Co-OH active site between Co(OH)₂ and CoSe regulates the hydrogen adsorption and desorption energy and fast electron transfer capability, which is responsible for the improved HER. Moreover, the Co(OH)₂@CoSe NRs can be further converted into CoOOH nanosheets which serve as OER active sites. Toward practical electrolytic cell applications, the Co(OH)₂@CoSe nanorods as both the cathode and anode achieved a current density of 100 mA cm^-2 at 1.94 V for overall water splitting, better than that of noble metal-based electrocatalysts.

Selective Oxidation of Benzylic C-H Bonds Catalyzed by Cu(II)/{PMo12}

Precise catalytic regulation of carbon radical generation by a highly active oxygen radical to abstract the H atom in a C-H bond is an effective method for the selective activation of C-H synthetic chemistry. Herein, we report a facile catalyst system with commercially available copper(II)/{PMo₁₂} to form a tert-butanol radical intermediate for the selective oxidation of benzylic C-H bonds. The reaction shows a broad range of substrates (benzyl methylene, benzyl alcohols) with good functional group tolerance and chemical selectivity. The corresponding carbonyl compounds were synthesized with good yields under mild conditions. DFT calculations and experimental analysis further demonstrated a reasonable carbon radical mechanism for this type of organic transformation reaction.

Poly(3,4-ethylenedioxythiophene) Bearing Pyridylboronic Acid Group for Specific Recognition of Sialic Acid

Conducting polymers tethered with molecular recognition elements are good candidates for biosensing applications such as detecting a target molecule with selectivity. We develop a new monomer, namely, 3,4-ethylenedioxythiophene bearing a pyridylboronic acid moiety (EDOT-PyBA), for label-free detection of sialic acid as a cancer biomarker. PyBA, which is known to show specific binding to sialic acid in acid conditions is used as a synthetic ligand instead of lectins. PyBA confirms the enhanced binding affinity for sialic acid at pH 5.0-6.0 compared with traditional phenylboronic acid. Poly(EDOT-PyBA) is electrodeposited on a planar glassy carbon electrode and the obtained film is successfully characterized by X-ray photoelectron spectroscopy, scanning electron microscopy, atomic force microscopy, water contact angle measurements, and electrochemical impedance spectroscopy. The specific interaction of PyBA with sialic acid at the solution/electrode interface is detected by differential pulse voltammetry in a dynamic range 0.1-3.0 mM with a detection limit of 0.1 mM for a detection time of 3 min. The sensitivity covers the total level of free sialic acid in human serum and the assay time is the shorter than that of other methods. The poly(EDOT-PyBA) electrode successfully detects spiked sialic acid in human serum samples. Owing to its processability, mass productivity, and robustness, polythiophene conjugated with "boronolectin" is a candidate material for developing point-of-care and wearable biosensors.

Rhodium(iii)-catalyzed C–H annulation of 2-acetyl-1-arylhydrazines with sulfoxonium ylides: synthesis of 2-arylindoles

An efficient Rh(iii)-catalyzed synthesis of 2-arylindole derivatives via intermolecular C–H annulation of arylhydrazines with sulfoxonium ylides was accomplished. A variety of 2-acetyl-1-arylhydrazines with sulfoxonium ylides were converted into 2-arylindoles in satisfactory yields. Excellent selectivity and good functional group tolerance of this transformation were also observed.

Rh(iii)-catalyzed intermolecular C–H annulation of arylhydrazines with sulfoxonium ylides for synthesis of 2-arylindole derivatives was well established.

Biological Visual Detection for Advanced Photocatalytic Oxidation toward Pesticide Detoxification

Photocatalytic oxidation treatment is an emerging and fast developed eco-friendly, energy-saving, and efficient advanced oxidation technology for degrading hazardous pesticides. The conventional chemical detection to evaluate the effects for this process depends on the broken chemical structure, only giving residual content and product chemical composition. However, it misses direct visual detection on the toxicity and the quantitative analysis of pesticide detoxification. Here, we develop a novel strategy to combine photocatalytic oxidation with a zebrafish biological model to provide a direct visual detection on the environmental detoxification. The mortality or deformity of zebrafish embryos (ZEs) acts as an indicator. Over the irradiation duration threshold, the mortality of ZEs decreases to 23.3% for pure chlorothalonil (CTL-P) after photocatalytic oxidation treatment for 1 h, and the deformity reduces to 13.3% for commercial CTL (CTL-C) after 30 min and to 3.33% for tetramethylthiuram disulfide (TMTD) after 20 min. The toxicity of CTL-C and TMTD could be completely removed by photocatalytic oxidation treatment and causes no damage to the ZE developmental morphology. Chemical analyses demonstrate the degradation of CTL into inorganic compounds and TMTD into small organic molecules. Among these highlighted heterogeneous photocatalysts (g-C₃N₄, BiVO₄, Ag₃PO₄, and P25), g-C₃N₄ exhibits the highest photocatalytic detoxification for CTL-P, CTL-C, and TMTD.

Nrf2-ARE signaling pathway regulates the expressions of A1R and ENT1 in the brain of epileptic rats

OBJECTIVE

To explore the behavioral changes and the expressions of the A1 receptor (A1R) and balanced nucleoside transporter-1 (ENT1) in the brain of epileptic rats after activating the NF-E2-related factor 2 (Nrf2)-ARE signaling pathway.

MATERIALS AND METHODS

Adult male Sprague-Dawley (SD) rats were randomly divided into normal control group, epilepsy group, and t-butylhydroquinone (tBHQ) group, with 10 rats in each group. Lithium-pilocarpine induced epilepsy model in rats was established. The first epileptic latency and seizure frequency within 1 hour were observed in each group using the Racine scoring system. HE (Hematoxylin and Eosin) staining was used to observe the pathological lesions in the brain tissue of each group. The expressions of A1R, ENT1, and relative genes in Nrf2-ARE pathway in rat hippocampus was detected by immunohistochemistry and Western blot.

RESULTS

Compared with rats in epileptic group, the first seizure latency was prolonged and the seizure frequency decreased in tBHQ group (p<0.05). The degree of brain lesions in tHBQ group was lighter than that of epilepsy group. ENT1 expression in rat hippocampus of epileptic group was significantly upregulated than that of normal control group and tBHQ group. Besides, the protein levels of A1R, Nrf2, HO-1, and ARE in rat hippocampus of epilepsy group markedly decreased compared with those of normal control group. However, protein expressions of A1R, Nrf2, HO-1, and ARE proteins in rat hippocampus of tBHQ group were markedly upregulated.

CONCLUSIONS

Activation of the Nrf2-ARE signaling pathway can reduce the pathological damage of rat hippocampal neurons, prolong the latency of seizures, and reduce the degree of epileptic seizure in rats.