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BACKGROUND: Hepatoid adenocarcinoma of the stomach (HAS) is an extremely rare and unique malignant gastric tumor with a significantly worse prognosis than non-hepatoid adenocarcinoma of the stomach (non-HAS). The present study explored the clinicopathological features of HAS and non-HAS patients to provide insights into HAS treatment strategies. METHODS: From December 26, 2023, we performed a comprehensive search of the PubMed, Web of Science, Cochrane Library, and Embase.com databases for relevant studies. Two authors independently screened the studies, evaluated their quality, extracted data, and performed the analyses. This study was registered with PROSPERO on January 2, 2024. RESULTS: Nine retrospective studies were included for analysis after screening 833 articles. A total of 350 and 924 patients were enrolled in the HAS and non-HAS groups, respectively. While no significant differences were observed in age, sex, tumor size, T3 or T4 stage, and N2 or N3 stage between the two groups, the HAS group exhibited higher rates of lymph node metastasis (OR = 1.93, 95% CI: 1.19-3.13, p = 0.007), liver metastasis (OR = 3.45, 95% CI: 2.26-5.28, p < 0.001), and vascular invasion (OR = 2.76, 95% CI: 2.05-3.71, p < 0.001). Additionally, the HAS group had lower 3-year survival rates (HR = 2.35, 95% CI: 1.70-3.25, p < 0.001) and 5-year survival rates (HR = 3.63, 95% CI: 1.49-8.88, p = 0.005), but lower rates of lymphatic permeation (OR = 0.68, 95% CI: 0.47-0.99, p = 0.040). CONCLUSION: Based on the current clinical evidence, patients with HAS present distinct clinicopathological features, greater invasiveness, and poorer prognosis than non-HAS patients. Further research is warranted to develop optimal treatment strategies for HAS.

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OBJECTIVE: This meta-analysis aimed to investigate the association between circulating human papillomavirus (HPV) cell-free DNA and oncological outcomes of cervical cancer patients. METHODS: Searches were performed in MEDLINE, Embase, and CENTRAL from their inception until 26 November 2023. Inclusion criteria were: (1) pathologically confirmed cervical cancer with available HPV test results; (2) detection of HPV cell-free DNA was performed in serum/plasma before or at end of treatment; (3) studies reported oncological outcomes of cervical cancer patients according to the levels of HPV cell-free DNA. Data extraction and study quality assessment were performed independently by two authors. Pooled hazard ratios and 95% confidence intervals were calculated using the inverse-variance method for survival outcomes. RESULTS: Five studies were finally included in this meta-analysis. Blood samples were collected from 167 patients before treatment, with 150 individuals available for analysis at the end of treatment. Furthermore, 82 patients with available samples at 3 months post-treatment were included in the analysis. The pooled results indicated a significant association between positive HPV cell-free DNA at end of treatment and worse progression-free survival in patients with cervical cancer (pooled hazard ratio: 5.49; 95 % confidence interval: 2.85-10.58; I2: 0 %). Similar findings were observed in patients with detectable HPV cell-free DNA at 3 months post-treatment (pooled hazard ratio: 7.86; 95 % confidence interval: 3.32-18.60; I2: 0 %). However, the detection of HPV cell-free DNA before treatment was not significantly associated with progression-free survival (pooled hazard ratio: 0.97; 95 % confidence interval: 0.55-1.71; I2: 0 %). CONCLUSION: Cervical cancer patients testing positive for HPV cell-free DNA at the end of treatment or 3 months post-treatment displayed significantly poorer oncological outcomes compared to those testing negative. Thus, personalized monitoring of HPV cell-free DNA holds promise as a prognostic biomarker for patients with cervical cancer.

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Minimally invasive surgery on treatment of early-stage cervical cancer is debatable. Traditional approaches of colpotomy are considered responsible for an inferior oncological outcome. Evidence on whether protective colpotomy could optimize minimally invasive technique and improve prognoses of women with early-stage cervical cancer remains limited. We produced a systematic review and meta-analysis to compare oncological outcomes of the patients treated by minimally invasive radical hysterectomy with protective colpotomy to those treated by open surgery according to existing literature. We explored PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov from inception to December 2022. Inclusion criteria were: (1) randomized controlled trials or observational studies published in English, (2) studies comparing minimally invasive radical hysterectomy with protective colpotomy to abdominal radical hysterectomy in early-stage cervical cancer, and (3) studies comparing survival outcomes. Two reviewers performed the screening, data extraction, and quality assessment independently. A total of 8 retrospective cohort studies with 2020 women were included in the study, 821 of whom were in the minimally invasive surgery group, and 1199 of whom were in the open surgery group. The recurrence-free survival and overall survival in the minimally invasive surgery group were both similar to that in the open surgery group (pooled hazard ratio, 0.88 and 0.78, respectively; 95% confidence interval, 0.56-1.38 and 0.42-1.44, respectively). Minimally invasive radical hysterectomy with protective colpotomy on treatment of early-stage cervical cancer had similar recurrence-free survival and overall survival compared to abdominal radical hysterectomy. Protective colpotomy could be a guaranteed approach to modifying minimally invasive technique.

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Evidence is emerging that microbial products and residues (necromass) contribute greatly to stable soil organic matter (SOM), which calls for the necessity of separating the microbial necromass from other SOM pools in models. However, the understanding on how microbial necromass stabilizes in soil, especially the mineral protection mechanisms, is still lacking. Here, we incubated 13 C- and 15 N-labelled microbial necromass in a series of artificial soils varying in clay minerals and metal oxides. We found the mineralization, adsorption and desorption rate constants of necromass nitrogen were higher than those of necromass carbon. The accumulation rates of necromass carbon and nitrogen in mineral-associated SOM were positively correlated with the specific surface area of clay minerals. Our results provide direct evidence for the protection role of mineral in microbial necromass stabilization and provide a platform for simulating microbial necromass separately in SOM models.

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OBJECTIVES: Fatigue has a considerable impact on the driver's vehicle and even the driver's own operating ability. METHODS: An intelligent algorithm is proposed for the problem that it is difficult to classify the degree of drowsiness generated by the driver during the driving process. By studying the driver's electrocardiogram (ECG) during driving, two models were established to jointly classify the ECG signals as awake, stress, and fatigue or drowsiness states for drowsiness levels. Firstly, the deep learning method was used to establish the model_1 to predict the drowsiness of the original ECG, and model_2 was developed using the combination of principal component analysis (PCA) and weighted K-nearest neighbor (WKNN) algorithm to classify the heart rate variability characteristics. Then, the drowsiness prediction results of the two models were weighted according to certain rules, and the hybrid learning model combining dilated convolution and bidirectional long short-term memory network with PCA and WKNN algorithm was established, and the mixed model was denoted as DiCNN-BiLSTM and PCA-WKNN (DBPW). Finally, the validity of the DBPW model was verified by simulation of the public database. RESULTS: The experimental results show that the average accuracy, sensitivity and F1 score of the test model in the dataset containing multiple drivers are 98.79, 98.81, and 98.79 % respectively, and the recognition accuracy for drowsiness or drowsiness state is 99.33 %. CONCLUSIONS: Using the proposed algorithm, it is possible to identify driver anomalies and provide new ideas for the development of intelligent vehicles.

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Manipulating microorganisms to increase soil organic carbon (SOC) in croplands remains a challenge. Soil microbes are important drivers of SOC sequestration, especially via their necromass accumulation. However, microbial parameters are rarely used to predict cropland SOC stocks, possibly due to uncertainties regarding the relationships between microbial carbon pools, community properties and SOC. Herein we evaluated the microbial community properties (diversity and network complexity), microbial carbon pools (biomass and necromass carbon) and SOC in 468 cropland soils across northeast China. We found that not only microbial necromass carbon but also microbial community properties (diversity and network complexity) and biomass carbon were correlated with SOC. Microbial biomass carbon and diversity played more important role in predicting SOC for maize, while microbial network complexity was more important for rice. Models to predict SOC performed better when the microbial community and microbial carbon pools were included simultaneously. Taken together our results suggest that microbial carbon pools and community properties influence SOC accumulation in croplands, and management practices that improve these microbial parameters may increase cropland SOC levels.

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BACKGROUND: Minimally invasive radical hysterectomy has been reported to increase the risk of cancer relapse and death compared with open surgery in women with early-stage cervical cancer. The use of a uterine manipulator is considered one of the risk factors. OBJECTIVES: To investigate whether women with early-stage cervical cancer treated with minimally invasive radical hysterectomy without using uterine manipulator have oncological outcomes similar to those of open surgery. SEARCH STRATEGY: Searches were performed in MEDLINE, Embase and CENTRAL from their inception until 31 March 2022. SELECTION CRITERIA: Inclusion criteria were: (1) randomised controlled trials or observational cohort studies published in English, (2) studies comparing minimally invasive radical hysterectomy without using a uterine manipulator with open radical hysterectomy in women with early-stage cervical cancer, and (3) studies comparing survival outcomes. DATA COLLECTION AND ANALYSIS: Two authors independently conducted data extraction and assessed study quality. We calculated the hazard ratios (HR) and the 95% confidence intervals (CI) using the inverse variance approach for survival outcome. MAIN RESULTS: Six observational studies with 2150 women were included. The minimally invasive surgery group had a significantly higher risk of cancer relapse compared with open surgery group (HR 1.55, 95% CI 1.15-2.10). CONCLUSIONS: Minimally invasive radical hysterectomy without using a uterine manipulator resulted in an inferior recurrence-free survival compared with open radical hysterectomy in the treatment of women with early-stage cervical cancer.

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To explore factors influencing the health-related quality of life of spouses of breast cancer patients and the suitable questionnaires for this purpose. A cross-sectional study was conducted in the Third Affiliated Hospital of Kunming Medical University. The spouses of breast cancer patients were included and evaluated via face-to-face interviews. Self-designed demographic characteristics and disease-related questionnaires, the 12-item health survey questionnaire (SF-12), the three-level European five-dimensional health status scale (EQ-5D-3L), and the Social Support Rate Scale (SSRS) were used. The internal consistency reliability measure Cronbach's coefficient, criterion-related validity, construct validity, and sensitivity were used to evaluate the applicability of the EQ-5D-3L. Univariate and multivariate analyses were performed to analyze the factors associated with the health-related quality of life of spouses of breast cancer patients. We investigated a total of 100 spouses of breast cancer patients. Cronbach's α, the internal consistency reliability coefficient, was 0.502. The EQ-5D-3L health utility score was moderately correlated with PCS-12 (r=0.46, p=0.0001) and weakly correlated with MCS-12 (r=0.35, p=0.0001). The EQ-5D-3L health utility score for the spouses of breast cancer patients was 0.870, and the EQ-VAS was 78.3. In multivariate analysis, social support and cognition of the treatment effect were factors that influenced the EQ-5D-3L health utility score. The EQ-5D-3L has good reliability, validity, and sensitivity for measuring the physiological aspects of the health-related quality of life of spouses of BC patients. EQ-5D-3L was considered suitable for this study.

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The detection of electrocardiogram (ECG) characteristic wave is the basis of cardiovascular disease analysis and heart rate variability analysis. In order to solve the problems of low detection accuracy and poor real-time performance of ECG signal in the state of motion, this paper proposes a detection algorithm based on segmentation energy and stationary wavelet transform (SWT). Firstly, the energy of ECG signal is calculated by segmenting, and the energy candidate peak is obtained after moving average to detect QRS complex. Secondly, the QRS amplitude is set to zero and the fifth component of SWT is used to locate P wave and T wave. The experimental results show that compared with other algorithms, the algorithm in this paper has high accuracy in detecting QRS complex in different motion states. It only takes 0.22 s to detect QSR complex of a 30-minute ECG record, and the real-time performance is improved obviously. On the basis of QRS complex detection, the accuracy of P wave and T wave detection is higher than 95%. The results show that this method can improve the efficiency of ECG signal detection, and provide a new method for real-time ECG signal classification and cardiovascular disease diagnosis.

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The cultivation of medical students'research ability promotes in them high-quality career development. In addition to classroom instruction of the theoretical knowledge concerning research, the systematic training and practice of scientific research skills outside the classroom is also vitally important. We established the Volunteer Team of Gastric Cancer Surgery with the features of standardization, progressiveness, and practicality in order to cultivate the thinking skills concerning research and the research ability of medical students. Our team is supported by the Department of Gastrointestinal Surgery, West China Hospital, Sichuan University. Taking clinical and basic research skills training as the focus of our work, we have organized systematic workshops focused on theoretical knowledge and research skills practice programs of divers forms. Our work helps improve the research ability of medical students, suggesting that research-oriented clubs play an active role in the cultivation of practical research ability of medical students and should be widely promoted.

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BACKGROUND: The benefit of removing the splenic lymph nodes in patients with proximal gastric cancer has been controversial. The purpose of our study was to investigate the importance of performing a splenic hilar lymph node dissection without splenectomy in patients undergoing total gastrectomy for gastric cancer. METHODS: From January 2006 to December 2015, we retrospectively reviewed patients who underwent a curative total gastrectomy for gastric cancer. Propensity score matching was used to balance any potential discrepancy of the other covariates between patients with and without splenic hilar lymph node dissection. Survival analysis, Cox univariate and multivariate analysis, and subgroups analysis were conducted to determine the value of splenic hilar lymph node dissection. After matching, 2 nomograms among patients with and without splenic hilar lymph node dissection were established respectively, the C-index, calibration curve and decision curve analysis were used to further evaluate the value of splenic hilar lymph node dissection. RESULTS: The rate of metastatic splenic hilar lymph nodes in the 274 patients undergoing splenic hilar lymph node dissection was 16.4% (45/274). Patients undergoing splenic hilar lymph node dissection had better survival outcomes than those not undergoing splenic hilar lymph node dissection before (P = .003) and after (P = .003) propensity score matching. Cox multivariate analysis also confirmed that splenic hilar lymph node dissection was an independent prognostic factor both before (hazard ratio 1.284, 95% confidence interval 1.042-1.583, P = .019) and after (hazard ratio 1.480, 95% confidence interval 1.156-1.894, P = .002) propensity score matching. Subgroup analysis indicted that splenic hilar lymph node dissection offered better survival outcomes for esophagogastric junctional adenocarcinoma (P < .001, P for interaction = .018). After propensity score matching, the nomogram of patients with splenic hilar lymph node dissection (C-index 0.735, 95% confidence interval 0.695-0.774) also indicated a statistically significant advantage compared with that without splenic hilar lymph node dissection (C-index 0.708, 95% confidence interval 0.668-0.748, P < .001). CONCLUSION: Our study suggests that spleen-preserving splenic hilar lymph node dissection should be an essential procedure among patients undergoing total gastrectomy.

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Increased soil nitrogen (N) from atmospheric N deposition could change microbial communities and functions. However, the underlying mechanisms and whether soil phosphorus (P) status are responsible for these changes still have not been well explained. Here, we investigated the effects of N and P additions on soil bacterial and fungal communities and predicted their functional compositions in a temperate forest. We found that N addition significantly decreased soil bacterial diversity in the organic (O) horizon, but tended to increase bacterial diversity in the mineral (A) horizon soil. P addition alone did not significantly change soil bacterial diversity but mitigated the negative effect of N addition on bacterial diversity in the O horizon. Neither N addition nor P addition significantly influenced soil fungal diversity. Changes in soil microbial community composition under N and P additions were mainly due to the shifts in soil pH and NO3- contents. N addition can affect bacterial functional potentials, such as ureolysis, N fixation, respiration, decomposition of organic matter processes, and fungal guilds, such as pathogen, saprotroph, and mycorrhizal fungi, by which more C probably was lost in O horizon soil under increased N deposition. However, P addition can alleviate or switch the effects of increased N deposition on the microbial functional potentials in O horizon soil and may even be a benefit for more C sequestration in A horizon soil. Our results highlight the different responses of microorganisms to N and P additions between O and A horizons and provides an important insight for predicting the changes in forest C storage status under increasing N deposition in the future.

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BACKGROUND: Deregulation of HER2 expression could affect the biological characteristics of gastric cancer cells and treatment option for gastric cancer patients. This research aims to investigate the impact of HER2 on biological characteristics of gastric cancer stem cells (GCSCs) and prognosis of gastric cancer patients. METHODS: HER2 knockdown in GCSCs were constructed by lentivirus transfection. Alterations of proliferation, self-renewal, invasion, migration, colony formation, and tumorigenicity of GCSCs were examined. The changes of gene expressions after HER2 interference in GCSCs were detected by gene microarray. The impact of concentration of serum HER2 and expression of HER2 in tumor tissues on survival of 213 gastric cancer patients was also analyzed. RESULTS: Down-regulation of HER2 decreased the self-renewal, colony formation, migration, invasion, proliferation, and chemotherapy resistance of GCSCs. However, the tumorigenicity of GCSCs in vivo was increased after down-regulation of HER2. The results of gene microarray showed that HER2 gene might regulate the signal transduction of mTOR, Jak-STAT, and other signal pathways and affect the biological characteristics of GCSCs. Furthermore, survival analyses indicated that patients with high concentration of HER2 in serum had a favorable overall survival. However, there was no significant correlation between expression of HER2 in tumor tissue and overall survival. CONCLUSION: Interference of HER2 in GCSCs decreased the capacity of self-renewal, proliferation, colony formation, chemotherapy resistance, invasion, and migration but might increase the tumorigenicity in vivo. Patients with high concentration of HER2 in serum seemed to have a favorable prognosis.

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Microbial-derived nitrogen (N) is now recognized as an important source of soil organic N. However, the mechanisms that govern the production of microbial necromass N, its turnover, and stabilization in soil remain poorly understood. To assess the effects of elevated temperature on bacterial and fungal necromass N production, turnover, and stabilization, we incubated 15 N-labeled bacterial and fungal necromass under optimum moisture conditions at 10°C, 15°C, and 25°C. We developed a new 15 N tracing model to calculate the production and mineralization rates of necromass N. Our results showed that bacterial and fungal necromass N had similar mineralization rates, despite their contrasting chemistry. Most bacterial and fungal necromass 15 N was recovered in the mineral-associated organic matter fraction through microbial anabolism, suggesting that mineral association plays an important role in stabilizing necromass N in soil, independently of necromass chemistry. Elevated temperature significantly increased the accumulation of necromass N in soil, due to the relatively higher microbial turnover and production of necromass N with increasing temperature than the increases in microbial necromass N mineralization. In conclusion, we found elevated temperature may increase the contribution of microbial necromass N to mineral-stabilized soil organic N.

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BACKGROUND: The prognostic significance of preoperative plasma fibrinogen in patients with operable gastric cancer remains under debate. This study aimed to elucidate the prognostic value of fibrinogen in gastric cancer patients underwent gastrectomy. METHODS: A total of 4351 patients with gastric cancer collected from three comprehensive medical centers were retrospectively evaluated. Patients were categorized by minimum P value using X-tile, while the baseline confounders for fibrinogen was balanced through propensity score matching (PSM). The relationships between fibrinogen and other clinicopathologic features were evaluated, and nomogram was constructed to assess its prognostic improvement compared with TNM staging system. RESULTS: Fibrinogen was significantly correlated with macroscopic type, tumor differentiation, tumor size, and T and N stage. The factors, fibrinogen and T stage as well as N stage, were identified to be independent prognostic factors after PSM. Nomogram based on fibrinogen demonstrated a smaller Akaike information criterion (AIC) and a larger concordance index (C-index) than TNM staging system, illustrating that fibrinogen might be able to improve the prognostic accuracy. CONCLUSIONS: Preoperative plasma fibrinogen levels in gastric cancer patients were significantly correlated with tumor progression, which could be regarded as a reliable marker for survival prognostic prediction.

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BACKGROUND: Obesity may impact surgical outcomes of gastrectomy. Whether visceral fat area (VFA) is a better obesity parameter than body mass index (BMI) is still controversial. The aim of this study is to compare the accuracy and effectiveness of VFA and BMI in predicting the short-term surgical outcomes of gastrectomy. METHODS: Patients who were diagnosed with gastric cancer were measured for BMI and VFA preoperatively and then divided into a VFA-H (VFA-high) group and VFA-L (VFA-low) group, at the cutoff point of 100 cm2, and a BMI-H (BMI-high) group and BMI-L (BMI-low) group, at the cutoff point of 25 kg/m2. The short-term surgical outcomes were compared between the different groups. RESULTS: In total, 276 patients were enrolled in this study; 55 (19.9%) patients were classified into the BMI-H group, and 122 (44.2%) patients were classified into the VFA-H group. There was a significant correlation between BMI and VFA (r = 0.652, p < 0.001). Compared with the VFA-L group, the VFA-H group had a higher incidence of postoperative complications (31.1% vs. 13.0%; p < 0.001), longer operation duration (270.0 (235.0-305.0) vs. 255.0 (223.8-295.0), p = 0.046), and more blood loss (100.0 (100.0-150.0) vs. 80.0 (80.0-100.0), p < 0.001), while the BMI-H group had more blood loss than the BMI-L group (100.0 (100.0-120.0) vs. 100.0(80.0-100.0), p = 0.006). Logistic regression showed that VFA was an independent risk factor for postoperative complications (odds ratio 2.813, 95% CI 1.523-5.194; p = 0.001). CONCLUSION: For gastric cancer patients, VFA is superior to BMI in accurately and effectively illuminating the impact of obesity on short-term surgical outcomes. TRIAL REGISTRATION: Clinicaltrials.gov: NCT02800005.

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BACKGROUND: Splenectomy was traditionally performed to dissect the splenic hilar lymph nodes. Considering the important functions of spleen, whether splenectomy would bring beneficial to gastric cancer patients is debatable. This meta-analysis aimed to make an updated evaluation on the effectiveness and safety of splenectomy. METHODS: Literature searches were performed to identify eligible RCTs concerning effectiveness or safety of splenectomy with gastrectomy from PubMed, MEDLINE, CBMdisc, EMBASE, and Cochrane Central Register of Controlled Trials. Two reviewers completed the study selection, data extraction, and quality assessment independently. The meta-analyses were performed by RevMan 5.3. RESULTS: A total of 971 patients from four studies were included (485 in splenectomy group and 486 in spleen preservation group). Splenectomy did not increase 5-year overall survival rate (RR=1.05, 95% CI: 0.96, 1.16) or increase postoperative mortality (RR=1.21, 95% CI: 0.41, 3.54). However, the analysis demonstrated that gastrectomy with splenectomy had significantly higher incidence of postoperative complications (RR=1.80, 95% CI: 1.33, 2.45). No significant differences were found in terms of the number of resected lymph nodes and reoperation rate; however, splenectomy had a tendency to prolong the duration of surgery and hospital stays. Subgroup analyses indicated that splenectomy could not increase overall survival rate for either whole or proximal gastric cancer. Sensitivity analyses also found similar results compared to the primary analyses. CONCLUSIONS: Splenectomy cannot benefit the survival of patients with tumor located at lesser curvature, and it could instead increase postoperative morbidity.

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We carried out an experiment including nitrogen addition (N, 50 kg N·hm-2·a-1), phosphorus addition (P, 25 kg P·hm-2·a-1) and both nitrogen and phosphorus addition (NP, 50 kg N·hm-2·a-1+25 kg P·hm-2·a-1) in a natural Korean pine broad-leaved mixed forest on Changbai Mountain to examine the effects of single and combined N and P additions on soil microbial community composition and amino sugar. The results showed that N and P addition significantly reduced total microbial biomass by 19.5% and 24.6% in the organic layer of soil, while P addition significantly reduced the biomass of bacteria and fungi by 23.8% and 19.3%, respectively. In the mineral layer, N, P and NP addition significantly increased total microbial biomass by 94.8%, 230.9%, and 115.0% respectively, while the biomass of bacteria and fungi were significantly increased under all the treatments. The fungi to bacteria ratio (F/B) was significantly increased in the organic layer by N addition, while was decreased in the mineral layer soil by NP addition. The Gram-positive bacteria to Gram-negative bacteria ratio showed positive response to N, P and NP addition. Soil amino sugars responded differently to different treatments. N, P and NP addition significantly decreased glucosamine content by 41.3%, 48.8% and 36.4% in the organic layer, while N and NP addition increased muramic acid content by 43.0% and 71.1%, respectively. The contents of glucosamine and muramic acid in the mineral layer did not change significantly in response to N addition but increased significantly in response to both P addition and NP addition. The glucosamine to muramic acid ratio in the organic layer significantly decreased under fertilization treatments, indicating that N and P addition increased the relative contribution of bacteria to soil organic carbon accumulation. The changes in soil amino sugar contents were closely related to the change in microbial community composition after N and P addition, both of which were affected by changes in soil chemical properties.

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BACKGROUND: The da Vinci robotic system was considered an effectively alternative treatment option for early gastric cancer patients in recent years. The aim of our study was to evaluate the safety and feasibility of robot-assisted gastrectomy in our center. METHODS: This study included 33 patients who underwent robot-assisted gastrectomy (RAG) and 88 patients who underwent laparoscopic-assisted gastrectomy (LAG) between January 2016 and April 2018. Clinicopathological characteristics, surgical parameters, postoperative recovery, and the learning curves of RAG were evaluated. RESULTS: Baseline characteristics between two groups were well balanced. The operation time of RAG was longer than that of LAG (333.1 ± 61.4 min vs. 290.6 ± 39.0 min, p = 0.001), and the estimated blood loss was 62.4 ± 41.2 ml in the RAG group and 77.7 ± 32.3 ml in the LAG group (p = 0.005), respectively. The mean number of examined lymph nodes in RAG was less than that in LAG (30.3 ± 10.2 vs. 37.4 ± 13.7, p = 0.008). However, RAG had an advantage in the dissection of No. 9 lymph nodes (3.4 ± 2.1 vs. 2.5 ± 1.6, p = 0.039). The incidence of postoperative complications was similar in both groups (p = 0.735). There were no significant differences in terms of postoperative recovery between the two groups. The learning curve of RAG showed that the CUSUM value decreased from the 8th case, which suggested a rapid learning curve among experienced surgeons on LAG operations. CONCLUSIONS: RAG was safe and feasible for gastric cancer patients, with superiority in the dissection of No. 9 lymph nodes.

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Two-dimensional (2D) PtSe2 shows the most prominent layer-dependent electrical properties among various 2D materials and high catalytic activity for hydrogen evolution reaction (HER), and therefore, it is an ideal material for exploring the structure-activity correlations in 2D systems. Here, starting with the synthesis of single-crystalline 2D PtSe2 with a controlled number of layers and probing the HER catalytic activity of individual flakes in micro electrochemical cells, we investigated the layer-dependent HER catalytic activity of 2D PtSe2 from both theoretical and experimental perspectives. We clearly demonstrated how the number of layers affects the number of active sites, the electronic structures, and electrical properties of 2D PtSe2 flakes and thus alters their catalytic performance for HER. Our results also highlight the importance of efficient electron transfer in achieving optimum activity for ultrathin electrocatalysts. Our studies greatly enrich our understanding of the structure-activity correlations for 2D catalysts and provide new insight for the design and synthesis of ultrathin catalysts with high activity.