[MRI features of lymphoepithelioma-like intrahepatic cholangiocarcinoma]

Objective: To investigate the MRI manifestations of lymphoepithelioma-like intrahep cholangiocarcinoma (LEL-ICC). Methods: MR images of 26 cases with LEL-ICC confirmed pathologically at Zhongshan Hospital Affiliated with Fudan University between March 2011 and March 2021 were retrospectively analyzed. The number, location, size, morphology, edges of lesions, non-scan signal intensity, cystic necrosis, enhancement mode, peak, and capsule, vascular invasion, lymph node metastasis, and other MR images were included for analysis. The apparent diffusion coefficient (ADC) value of the lesion and the surrounding normal liver parenchyma were measured. A paired-sample t-test was used to statistically analyze the measurement data. Results: All 26 cases of LEL-ICC had solitary lesions. Mass-type LEL-ICC was the most common [n=23, lesion size (4.02±2.32) cm] with distribution along the bile duct [n=3, lesion size (7.23±1.40 cm)]. Among the 23 lesions of mass type LEL-ICC, most of the lesions were close to the liver capsule (n=20), round (n=22), clearly bordered (n=13), and cystic necrosis (n=22). In the three lesions of LEL-ICC distributed along the bile duct, most of them were close to the liver capsule (n=2), irregular (n=3), blurred edges (n=3), and cystic necrosis (n=3). All 26 lesions showed a low/slightly low signal on T₁WI, a high/slightly high signal on T₂WI, and a slightly high or high signal on DWI. Three lesions showed fast-in and fast-out enhancement modes, and 23 lesions showed continuous enhancement. Twenty-five lesions showed peak enhancement in the arterial phase, and one lesion appeared in the delayed phase. The ADC value of 26 lesions and adjacent normal liver parenchyma was (1.112±0.274)×10^-3 mm²/s and (1.482±0.346)×10^-3 mm²/s, respectively, and the both had a statistically significant difference (P<0.05). Conclusion: Certain manifestations of LEL-ICC in magnetic resonance imaging are advantageous for diagnosis and differential diagnosis.

Three-Dimensional Microtumor Formation of Infantile Hemangioma-Derived Endothelial Cells for Mechanistic Exploration and Drug Screening

Infantile hemangioma (IH) is the most prevalent type of vascular tumor in infants. The pathophysiology of IH is unknown. The tissue structure and physiology of two-dimensional cell cultures differ greatly from those in vivo, and spontaneous regression often occurs during tumor formation in nude mice and has severely limited research into the pathogenesis and development of IH. By decellularizing porcine aorta, we attempted to obtain vascular-specific extracellular matrix as the bioink for fabricating micropattern arrays of varying diameters via microcontact printing. We then constructed IH-derived CD31+ hemangioma endothelial cell three-dimensional microtumor models. The vascular-specific and decellularized extracellular matrix was suitable for the growth of infantile hemangioma-derived endothelial cells. The KEGG signaling pathway analysis revealed enrichment primarily in stem cell pluripotency, RAS, and PI3KAkt compared to the two-dimensional cell model according to RNA sequencing. Propranolol, the first-line medication for IH, was also used to test the model's applicability. We also found that metformin had some impact on the condition. The three-dimensional microtumor models of CD31+ hemangioma endothelial cells were more robust and efficient experimental models for IH mechanistic exploration and drug screening.

Chemical-free pressure washing system as pretreatment to harvest cathode materials

Recycling cathode materials from spent lithium-ion batteries has the potential to reduce damages to the environment and human health due to hazardous waste treatment, and mitigate supply risks of raw materials. Related political incentives or regulations have led to increased research and development efforts on cathode recycling. Promising approaches include direct recycling and hydrometallurgical processes, where delamination is the first step after collection of cathodes. In this study, we examined a pressure washing system's ability to harvest cathode materials. A high-pressure water jet provides strong forces to overcome the adhesion provided by organic binders. Four factors (water pressure, distance between nozzle and cathode, incident angle of water jet, and nozzle type) were investigated using a 3^4-1 fractional factorial design to screen important parameters and find the optimal conditions. Compared with other delamination processes where chemical reagents and heating are involved, the chemical-free pressure washing system can achieve separation in a few seconds (∼74 min/m²) at room temperature, which remarkably improves the efficiency of delamination. The particle size of recycled products (D50 of 31.87 μm) is significantly reduced without Al contamination from current collectors or morphological damages. In addition, three types of recycled cathode materials were used as inputs for the acid leaching process. High leaching efficiencies of lithium (>90 %) and cobalt (>85 %) suggest that the pressure washing system could be a practical, economical, and eco-friendly pretreatment process to harvest cathode materials.

Unraveling schizophrenia replicable functional connectivity disruption patterns across sites

Functional connectivity (FC) disruption is a remarkable characteristic of schizophrenia. However, heterogeneous patterns reported across sites severely hindered its clinical generalization. Based on qualified nodal-based FC of 340 schizophrenia patients (SZ) and 348 normal controls (NC) acquired from seven different scanners, this study compared four commonly used site-effect correction methods in removing the site-related heterogeneities, and then tried to cluster the abnormal FCs into several replicable and independent disrupted subnets across sites, related them to clinical symptoms, and evaluated their potentials in schizophrenia classification. Among the four site-related heterogeneity correction methods, ComBat harmonization (F1 score: 0.806 ± 0.145) achieved the overall best balance between sensitivity and false discovery rate in unraveling the aberrant FCs of schizophrenia in the local and public data sets. Hierarchical clustering analysis identified three replicable FC disruption subnets across the local and public data sets: hypo-connectivity within sensory areas (Net1), hypo-connectivity within thalamus, striatum, and ventral attention network (Net2), and hyper-connectivity between thalamus and sensory processing system (Net3). Notably, the derived composite FC within Net1 was negatively correlated with hostility and disorientation in the public validation set (p < .05). Finally, the three subnet-specific composite FCs (Best area under the receiver operating characteristic curve [AUC] = 0.728) can robustly and meaningfully discriminate the SZ from NC with comparable performance with the full identified FCs features (best AUC = 0.765) in the out-of-sample public data set (Z = -1.583, p = .114). In conclusion, ComBat harmonization was most robust in detecting aberrant connectivity for schizophrenia. Besides, the three subnet-specific composite FC measures might be replicable neuroimaging markers for schizophrenia.

Impact of local living environment on innovation efficiency of high-tech industries in China: a spatial analysis

Environmental problems not only relate to residents' happiness but also challenge the innovation development of industries. This study first measures the innovation efficiency of China's high-tech industries using the super-efficiency data envelopment analysis model and portrays its spatial characteristics through the Moran's I index and the local indicators of spatial association map. Second, we use the entropy weight method to construct the local living environment index from both natural and social environments. Finally, we utilize spatial econometric models to analyze the impact of local living environment on high-tech industries' innovation efficiency. The results reveal that, first, the spatial variation of innovation efficiency in China's high-tech industries is significant, with efficiency being higher in the east than the Midwest, and higher in the south than the north. Second, innovation efficiency has a positive adjacent and geographical spatial autocorrelation, and low-low agglomeration and low-high agglomeration dominate the types of spatial correlation. Finally, the contribution of the local living environment to the innovation efficiency of high-tech industries is positive and significant. This contribution has an obvious spatial spillover effect and regional heterogeneity. This study can help regional governments to improve local living environments and promote industrial innovation and development.

Factors associated with depression in residents in the post-epidemic era

OBJECTIVE

To explore the factors associated with depression in residents in the post-epidemic era of COVID-19.

METHODS

A multi-stage stratified random sampling method was used to conduct a questionnaire survey among community residents through self-designed questionnaires and self-rating depression scale (SDS). Multivariate logistic regression analysis was performed on the influencing factors of depressive symptoms.

RESULTS

A total of 1993 residues completed the survey of depression status. The incidence of depressive symptoms was 27.04%. The multivariate logistic regression analysis showed that female (odds ratio (OR): 6.239, 95% confidence interval (CI): 2.743-10.698), body mass index (BMI) > 24 (OR: 2.684, 95% CI: 1.059-3.759) and drinking (OR: 1.730, 95% CI: 1.480-3.153) were the risk factors for developing depressive symptoms. Married (OR: 0.417, 95% CI: 0.240-0.652), monthly income (3001-5000 yuan, OR: 0.624, 95% CI: 0.280-0.756; >5000 yuan, OR: 0.348, 95% CI: 0.117-0.625), ordinary residents (OR: 0.722, 95% CI: 0.248-0.924) and urban residents (OR: 0.655, 95% CI: 0.394-0.829) were the protective factors of depressive symptoms.

CONCLUSIONS

Under the post-epidemic era of COVID-19, depressive symptoms are still common among community residents in China. Gender, BMI, drinking, marriage, monthly income and nature of personnel and residential area are associated with the incidence of depressive symptoms.

[Association of nutritional status with clinical outcomes of stroke patients with acute anterior circulation large vessel occlusion after emergency endovascular treatment]

OBJECTIVE

To explore the influence of nutritional status on 90-day functional outcomes of stroke patients with acute large vessel occlusion in the anterior circulation after endovascular treatment (EVT).

METHODS

We retrospectively analyzed the baseline, laboratory, surgical and 90-day follow-up data of patients with stroke resulting from acute large vessel occlusion in the anterior circulation, who underwent emergency endovascular treatment in our hospital from July, 2015 to December, 2020. A favorable outcome was defined as a modified Rankin scale score ≤2 at 90 days. Univariate and multivariate regression analyses were performed to explore the relationship between nutritional status and 90-day functional outcomes of the patients.

RESULTS

A total of 459 patients (mean age of 68.29±11.21 years, including 260 males) were enrolled in this study. According to their prognostic nutritional index (PNI), the patients were divided into normal nutrition group (392 cases, 85.4%), moderate malnutrition group (44 cases, 9.6%), and severe malnutrition group (23 cases, 5.0%). Univariate analysis showed that the patients with good clinical outcomes had a lower proportion of malnutrition with a younger age, a lower rate of diabetes, lower baseline blood pressure, lower baseline NIHSS score, higher baseline ASPECT score, and higher rates of good collateral circulation and complete vascular recanalization. Multivariate analysis showed that in addition to age, diabetes, baseline systolic blood pressure, successful recanalization, baseline ASPECT score, baseline NIHSS score and collateral circulation, a greater PNI was a protective factor for a good 90-day outcome of patients after EVT (moderate vs severe: OR=0.245, 95% CI: 0.066-0.908, P=0.035; normal vs severe: OR=0.185, 95% CI: 0.059-0.581, P=0.004).

CONCLUSION

Nutritional status an important factor affecting the 90-day outcomes after EVT of stroke patients with acute large vessel occlusion in the anterior circulation.

[Autophagy promotes recurrence of nasopharyngeal carcinoma via inducing the formation of dormant polyploid giant cancer cells]

Objective: To explore the effect of dormant polyploid giant cancer cells (PGCC) on nasopharyngeal carcinoma (NPC) recurrence and to clarify the role of inhibition of autophagy in inhibiting NPC-PGCC formation and preventing NPC recurrence. Methods: NPC cells-derived PGCC (NPC-PGCC) were induced by paclitaxel (PTX), and the morphology, polyploid characteristics and cell activity of PGCC were identified by light microscopy, immunofluorescence and Live/Dead cell double staining assays. RNA-seq was used to analyze the differentially expressed genes between NPC-PGCC and diploid nasopharyngeal carcinoma cells CNE2. Functional enrichment and pathway annotation analysis of differentially expressed genes were performed using Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG). The level of autophagy in NPC-PGCC cells was assessed by Western Blot and transmission electron microscopy analysis. The role of autophagy in the formation of NPC-PGCC and the effect of NPC-PGCC on the recurrence of nasopharyngeal carcinoma were studied using a highly clinically relevant mouse nasopharyngeal carcinoma recurrence model. Statistical analysis was performed using GraphPad Prism 6 and P-values<0.05 were considered statistically significant. Results: NPC-PGCC induced by paclitaxel had the characteristics of burst-like division after dormancy. GO enrichment and KEGG pathway analyses identified the significant biological processes and pathways mainly concentrated in autophagy and related pathways involving the differentially expressed genes between NPC-PGCC and diploid nasopharyngeal carcinoma cells CNE2. The autophagy level was significantly enhanced in NPC-PGCC cells. In a highly clinically relevant mouse nasopharyngeal carcinoma recurrence model, the number of PGCC in the primary tumor of the nude mice treated with cisplatin were higher than those of the other groups. In nude mice pretreated with autophagy inhibitor and then co-treatment with autophagy inhibitor and cisplatin, the number of PGCC in primary tumors was less and the recurrence rate was significantly lower than in other groups. Conclusions: The mechanism of dormant polyploid giant cancer cells formation is related to autophagy. Inhibition of autophagy can inhibit the formation of PGCC and thus prevent the recurrence of nasopharyngeal carcinoma.

[Smith-Kingsmore syndrome caused by MTOR gene variation: 2 cases and literature review]

Objective: To investigate the clinical manifestations and genetic features of 2 children with Smith-Kingsmore syndrome caused by MTOR gene variation and review the literature. Methods: The clinical data of 2 children carrying MTOR gene variant, diagnosed at Xi'an Children's Hospital from April 2018 to April 2021, were retrospectively summarized."MTOR"and"Smith-Kingsmore syndrome"were used as key words to search at China National Knowledge Infrastructure, Wanfang Data Knowledge Service Platform, PubMed and OMIM up to August 2021. The characteristics of MTOR gene variation and the clinical phenotype of children with Smith-Kingsmore syndrome were summarized. Results: Two children were both females, aged 1.5 years and 2 years respectively, the onset age were both in infancy. They both had developmental delay, megalencephaly and abnormal face. Both whole exome sequencing revealed a de novo heterozygous missense variant in MTOR gene. One case carried c.5395G>A (p.Glu1799Lys) and the other case carried c.7234G>C (p.Asp2412His). There was no literature of MTOR gene variation in Chinese. So far, a total of 45 cases were reported worldwide with detailed clinical information. Eleven variations in MTOR gene were involved, which were all heterozygous missense mutations. Among them, p.Glu1799Lys was the most common sites (28 cases,62%). Another case carried c.7234G>C (p.Asp2412His) was not reported before. Summarizing the 47 cases (including these 2 cases), 46 cases had developmental delay or intellectual disability, 9 cases had developmental regression,42 cases had megalencephaly, 30 cases had facial malformation,16 cases had hypotonia, 17 cases had autism spectrum disorders, 3 cases had hyperactivity, 3 cases had obsessive compulsive disorder, 13 cases had eye diseases, 11 cases had cutaneous vascular malformation, and 9 cases had hypoglycemia. Conclusions: The main clinical features of Smith-Kingsmore syndrome include megalencephaly, developmental delay or intellectual disability, and facial malformation, which can be combined with epilepsy, autism spectrum disorder, hypotonia, hypoglycemia and so on. The variation of MTOR gene is the cause of Smith-Kingsmore syndrome.

[Clinical characteristics of 272 437 patients with different histopathological subtypes of primary esophageal malignant tumors]

Objective: To characterize the histopathological subtypes and their clinicopathological parameters of gender and onset age by common, rare and sparse primary esophageal malignant tumors (PEMT). Methods: A total of 272 437 patients with PEMT were enrolled in this study, and all of the patients were received radical surgery. The clinicopathological information of the patients was obtained from the database established by the State Key Laboratory of Esophageal Cancer Prevention & Treatment from September 1973 to December 2020, which included the clinical treatment, pathological diagnosis and follow-up information of esophagus and gastric cardia cancers. All patients were diagnosed and classified by the criteria of esophageal tumor histopathological diagnosis and classification (2019) of the World Health Organization (WHO). The esophageal tumors, which were not included in the WHO classification, were analyzed separately according to the postoperative pathological diagnosis. The χ² test was performed by the SPSS 25.0 software on count data, and the test standard α=0.05. Results: A total of 32 histopathological types were identified in the enrolled PEMT patients, of which 10 subtypes were not included in the WHO classification. According to the frequency, PEMT were divided into common (esophageal squamous cell carcinoma, ESCC, accounting for 97.1%), rare (esophageal adenocarcinoma, EAC, accounting for 2.3%) and sparse (mainly esophageal small cell carcinoma, malignant melanoma, etc., accounting for 0.6%). All the common, rare, and sparse types occurred predominantly in male patients, and the gender difference of rare type was most significant (EAC, male∶ female, 2.67∶1), followed with common type (ESCC, male∶ female, 1.78∶1) and sparse type (male∶ female, 1.71∶1). The common type (ESCC) mainly occurred in the middle thoracic segment (65.2%), while the rare type (EAC) mainly occurred in the lower thoracic segment (56.8%). Among the sparse type, malignant melanoma and malignant fibrous histiocytoma were both predominantly located in the lower thoracic segment (51.7%, 66.7%), and the others were mainly in the middle thoracic segment. Conclusion: ESCC is the most common type among the 32 histopathological types of PEMT, followed by EAC as the rare type, and esophageal small cell carcinoma and malignant melanoma as the major sparse type, and all of which are mainly occur in male patients. The common type of ESCC mainly occur in the middle thoracic segment, while the rare type of EAC mainly in the lower thoracic segment. The mainly sparse type of malignant melanoma and malignant fibrous histiocytoma predominately occur in the lower thoracic segment, and the remaining sparse types mainly occur in the middle thoracic segment.

U-shaped association between serum albumin and pediatric intensive care unit mortality in critically ill children

Introduction

The detailed association between albumin levels and mortality has not been studied in critically ill children. The aim of this study was to reveal an association between albumin levels in detail and mortality in critically ill children.

Materials and methods

We retrospectively collected data from children admitted to four pediatric intensive care units (PICUs) in China between January 2015 and October 2020. Restricted cubic spline curves based on logistic regression models were generated to evaluate the detailed associations between serum albumin levels and PICU mortality. Threshold effect analysis was performed using two piecewise regression models.

Results

The study included 9,123 children. The overall mortality was 5.3%. The detailed association between serum albumin levels and the risk of mortality followed a U-shape. The risk of mortality decreased with increasing serum albumin levels (OR = 0.919; 95% CI: 0.886, 0.954) in children with serum albumin levels < 43.2 g/L and increased with increasing serum albumin levels (OR = 1.174; 95% CI: 1.044, 1.316) in children with serum albumin levels ≥ 43.2 g/L.

Conclusion

There was a U-shaped association between serum albumin levels and mortality in critically ill children in the PICU.

Evidence for Nonlinear Gluon Effects in QCD and Their Mass Number Dependence at STAR

The STAR Collaboration reports measurements of back-to-back azimuthal correlations of di-π^{0}s produced at forward pseudorapidities (2.6<η<4.0) in p+p, p+Al, and p+Au collisions at a center-of-mass energy of 200 GeV. We observe a clear suppression of the correlated yields of back-to-back π^{0} pairs in p+Al and p+Au collisions compared to the p+p data. The observed suppression of back-to-back pairs as a function of transverse momentum suggests nonlinear gluon dynamics arising at high parton densities. The larger suppression found in p+Au relative to p+Al collisions exhibits a dependence of the saturation scale Q_{s}^{2} on the mass number A. A linear scaling of the suppression with A^{1/3} is observed with a slope of -0.09±0.01.

[Effects of cinepazide maleate injection on blood pressure in patients with acute ischemic stroke and hypertension]

Objective: To investigate the blood pressure change in patients with acute ischemic stroke (AIS) and hypertension treated with cinepazide maleate injection. Methods: This was a subgroup analysis of post-marketing clinical confirmation study of cinepazide maleate injection for acute ischemic stroke: a randomized, double-blinded, multicenter, placebo-parallel controlled trial, which conducted in China from August 2016 to February 2019. Eligible patients fulfilled the inclusive criteria of acute anterior circulation ischemic stroke with National Institutes of Health Stroke Scale (NIHSS) scores of 7-25. The primary endpoints were mean blood pressure of AIS patients treated with cinepazide maleate or control, which were assessed during the treatment period (14 days), and the proportion of the patients with normal blood pressure was analyzed after the treatment period. Furthermore, a subgroup analysis was performed to investigate a possible effect of the history of hypertension on outcomes. Results: This analysis included 809 patients with hypertension. There was no significant difference in patients blood pressure and the proportion of patients with normal blood pressure (60.5% vs. 59.0%,P>0.05) between cinepazide maleate group and control group. Conclusion: Administration of cinepazide maleate injection does not affect the management of clinical blood pressure in patients with AIS.

[Pancreas multidisciplinary team optimizes the diagnosis and treatment of pancreas-related diseases and improves the prognosis of pancreatic cancer patients]

Objectives: To evaluate the role of pancreas multidisciplinary team(MDT) clinic in the diagnosis of pancreatic diseases,patient compliance with MDT advice,and the impact of MDT on the postoperative survival of patients with pancreatic cancer. Methods: The study included 927 patients(554 males,373 females,aged (58.1±13.3)years (range: 15 to 89 years)) that had visited the pancreas MDT clinic of Zhongshan Hospital from May 2015 to December 2021,and 677 patients(396 males, 281 females, aged (63.6±8.9)years(range: 32 to 95 years)) who underwent radical surgery and with pathologically confirmed pancreatic adenocarcinoma from January 2012 to December 2020,of whom 79 patients had attended the pancreas MDT. The clinical and pathological data were collected and analyzed retrospectively. Diseases were classified in accordance with 2010 WHO classification of tumors of the digestive system and usual clinical practices. The Kaplan-Meier method was used for drawing the survival curve and calculating the survival rate. The univariate analysis was done by Log-rank test and the multivariate analysis was done by COX proportional hazards model. Survival rates were compared using χ2 test. Results: Among the 927 patients that had visited the MDT clinic,233 patients(25.1%) were referred due to undetermined diagnosis. A direct diagnosis was made in 109 cases (46.8%,109/233) by the MDT clinic, of which 98 were consistent with the final diagnosis,resulting in an accuracy of 89.9%(98/109). The direct diagnosis rate in the recent years(36.6%(41/112),from June 2019 to December 2021) decreased compared to that in the previous years(56.2%(68/121),from May 2015 to May 2019),yet the accuracy in the recent years(90.2%,37/41) was basically the same as before (89.7%,61/68). The rate of compliance of the entire cohort was 71.5%(663/927), with the compliance rate in the recent two and a half years(81.4%,338/415) remarkably higher than that in the previous four years(63.4%,325/512). Patients with pancreatic cancer that attended the MDT exhibited a trend toward longer median postoperative survival than patients that did not attend the MDT,but the difference was not statistically significant(35.2 months vs.30.2 months,P>0.05). The 1-year and 3-year survival rates of patients that attended the MDT were significanly higher than patients that did not attend the MDT(88.6% vs. 78.4%,P<0.05;32.9% vs. 21.9%,P<0.05,respectively),but the 5-year survival rate was not statistically different(7.6% vs. 4.8%,P>0.05). Conclusions: The pancreas MDT clinic is an accurate and convenient way to diagnose intractable pancreatic diseases,and in the recent years the patients' compliance rate with MDT advice has increased. Pancreatic cancer patients that have attended the MDT have higher 1-year and 3-year postoperative survival rates,but the long-term survival benefits of MDT still needs to be proved by clinical studies on a larger scale.

Transumbilical single-site two incision laparoscopic pyloromyotomy for pediatric hypertrophic pyloric stenosis

PURPOSE

A new novel technique for the treatment of pediatric hypertrophic pyloric stenosis (HPS), transumbilical single-site laparoscopic pyloromyotomy with a single instrument (TUSSLP), was introduced. TUSSLP was compared with the transabdominal three-site laparoscopic pyloromyotomy (TATSLP) procedure.

METHODS

Patients with HPS who underwent TUSSLP and TATSLP between January 2016 and September 2020 were assigned to group A and group B, respectively. The descriptive variables, perioperative clinical characteristics and postoperative follow-up results were retrospectively analyzed and compared between the 2 groups. The primary outcome of this study was the rate of switching to conventional pyloromyotomy.

RESULTS

Sixty-four patients were enrolled in this study. Of these patients, 29 (22 males, 7 females, 54.4 ± 22.6 days) who received TUSSLP were assigned to group A. The remaining 35 (28 males, 7 females, 54.5 ± 27.6 days) who received TATSLP were assigned to group B. The data of preoperative patient variables were comparable between the 2 groups (P > 0.05). The mean operative time (ORT) was 28.1 ± 5.6 min in group A, which was not significantly different from 25.8 ± 3.1 min in group B (P = 0.25). The other perioperative features were not significantly different between the 2 groups (P > 0.05). During follow-up (39.1 ± 14.7 m in group A and 35.4 ± 16.1 m in group B, P = 0.51), no significant difference was observed in the overall incidence of vomiting between the 2 groups (P = 0.26).

CONCLUSIONS

TUSSLP is a feasible and reliable minimally invasive method for HPS. It has the advantages of an improved cosmetic appearance. The postoperative follow-up results of TUSSLP are comparable with those of TATSLP.

Classification models and SAR analysis on thromboxane A2 synthase inhibitors by machine learning methods

Thromboxane A2 synthase (TXS) is a promising drug target for cardiovascular diseases and cancer. In this work, we conducted a structure-activity relationship (SAR) study on 526 TXS inhibitors for bioactivity prediction. Three types of descriptors (MACCS fingerprints, ECFP4 fingerprints, and MOE descriptors) were utilized to characterize inhibitors, 24 classification models were developed by support vector machine (SVM), random forest (RF), extreme gradient boosting (XGBoost), and deep neural networks (DNN). Then we reduced the number of fingerprints according to the contribution of descriptors to the models, and constructed 16 extra models on simplified fingerprints. In general, Model_4D built by DNN algorithm and 67 bits MACCS fingerprints performs best. The prediction accuracy of the model on the test set is 0.969, and Matthews correlation coefficient (MCC) is 0.936. The distance between compound and model (dSTD-PRO) was used to characterize the application domain of the model. In the test set of Model_4D, dSTD-PRO of 91.5% compounds is lower than the corresponding training set threshold (threshold0.90 = 0.1055), and the accuracy of these compounds is 0.983. In addition, the important descriptors were summarized and further analyzed. It showed that aromatic nitrogenous heterocyclic groups were beneficial to improve the bioactivity of TXS inhibitors.