Fascia- vs vessel-oriented lateral lymph node dissection for rectal cancer: Short-term outcomes and prognosis in a single-center experience.

BACKGROUND: For the management of lateral lymph node (LLN) metastasis in patients with rectal cancer, selective LLN dissection (LLND) is gradually being accepted by Chinese scholars. Theoretically, fascia-oriented LLND allows radical tumor resection and protects of organ function. However, there is a lack of studies comparing the efficacy of fascia-oriented and traditional vessel-oriented LLND. Through a preliminary study with a small sample size, we found that fascia-oriented LLND was associated with a lower incidence of postoperative urinary and male sexual dysfunction and a higher number of examined LLNs. In this study, we increased the sample size and refined the postoperative functional outcomes. AIM: To compare the effects of fascia- and vessel-oriented LLND regarding short-term outcomes and prognosis. METHODS: We conducted a retrospective cohort study on data from 196 patients with rectal cancer who underwent total mesorectal excision and LLND from July 2014 to August 2021. The short-term outcomes included perioperative outcomes and postoperative functional outcomes. The prognosis was measured based on overall survival (OS) and progression-free survival (PFS). RESULTS: A total of 105 patients were included in the final analysis and were divided into fascia- and vessel-oriented groups that included 41 and 64 patients, respectively. Regarding the short-term outcomes, the median number of examined LLNs was significantly higher in the fascia-oriented group than in the vessel-oriented group. There were no significant differences in the other short-term outcomes. The incidence of postoperative urinary and male sexual dysfunction was significantly lower in the fascia-oriented group than in the vessel-oriented group. In addition, there was no significant difference in the incidence of postoperative lower limb dysfunction between the two groups. In terms of prognosis, there was no significant difference in PFS or OS between the two groups. CONCLUSION: It is safe and feasible to perform fascia-oriented LLND. Compared with vessel-oriented LLND, fascia-oriented LLND allows the examination of more LLNs and may better protect postoperative urinary function and male sexual function.

The safety and prognosis of radical surgery in colorectal cancer patients over 80 years old.

OBJECTIVE: The purpose of this study was to assess the safety and feasibility of radical surgery and to investigate prognostic factors influencing in colorectal cancer (CRC) patients over the age of 80. METHODS: Between January 2010 and December 2020, 372 elderly CRC patients who underwent curative resection at the National Cancer Center were enrolled in the study. Preoperative clinical characteristics, perioperative outcomes, and postoperative pathological features were all collected. RESULTS: A total of 372 elderly patients with colorectal cancer were included in the study, including 226 (60.8%) men and 146 (39.2%) women. A total of 219 (58.9%) patients had a BMI < 24 kg/m2, and 153 (41.1%) patients had a BMI ≥ 24 kg/m2. The mean operation time and intraoperative blood loss were 152.3 ± 58.1 min and 67.6 ± 35.4 ml, respectively. The incidence of overall postoperative complications was 28.2% (105/372), and the incidence of grade 3-4 complications was 14.7% (55/372). In the multivariable Cox regression analysis, BMI ≥ 24 kg/m2 (HR, 2.30, 95% CI, 1.27-4.17; P = 0.006) and N1-N2 stage (HR: 2.97; 95% CI, 1.48-5.97; P = 0.002) correlated with worse CSS. CONCLUSION: The findings of this study showed that radical resection for CRC is safe and feasible for patients over the age of 80. After radical resection, BMI and N stage were independent prognostic factors for elderly CRC patients.

HAMP as a Prognostic Biomarker for Colorectal Cancer Based on Tumor Microenvironment Analysis.

Colorectal cancer (CRC) is the most common digestive tumor in the world and has a high mortality rate. The development and treatment of CRC are related to the immune microenvironment, but immune response-related prognostic biomarkers are lacking. In this study, we used The Cancer Genome Atlas (TCGA) to explore the tumor microenvironment (TME) and weighted gene coexpression network analysis (WGCNA) to identify significant prognostic genes. We also identified differentially expressed genes in the TCGA data and explored immune-related genes and transcription factors (TFs). Then, we built a TF regulatory network and performed a comprehensive prognostic analysis of an lncRNA-associated competitive endogenous RNA network (ceRNA network) to build a prognostic model. CCR8 and HAMP were identified both in the WGCNA key module and as immune-related genes. HAMP had good prognostic value for CRC and was highly expressed in CRC tissues and had a negative correlation with CD4+ T cells and M0 macrophages based on immunohistochemistry and immunofluorescence staining of clinical specimens.We found that HAMP had high prognostic and therapeutic target value for CRC and was associated with liver metastasis. These analysis results revealed that HAMP may be a candidate immune-related prognostic biomarker for CRC.

Reduced serum high-density lipoprotein cholesterol levels and aberrantly expressed cholesterol metabolism genes in colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) is a common malignant tumor of the gastrointestinal tract. Lipid metabolism, as an important part of material and energy circulation, is well known to play a crucial role in CRC. AIM: To explore the relationship between serum lipids and CRC development and identify aberrantly expressed cholesterol metabolism genes in CRC. METHODS: We retrospectively collected 843 patients who had confirmed CRC and received surgical resection from 2013 to 2015 at the Cancer Hospital of the Chinese Academy of Medical Sciences as our research subjects. The levels of serum total cholesterol (TC), triglycerides, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), LDL-C/HDL-C and clinical features were collected and statistically analyzed by SPSS. Then, we used the data from Oncomine to screen the differentially expressed genes (DEGs) of the cholesterol metabolism pathway in CRC and used Gene Expression Profiling Interactive Analysis to confirm the candidate DEGs. PrognoScan was used to analyze the prognostic value of the DEGs, and Search Tool for the Retrieval of Interacting Genes was used to construct the protein-protein interaction network of DEGs. RESULTS: The serum HDL-C level in CRC patients was significantly correlated with tumor size, and patients whose tumor size was more than 5 cm had a lower serum HDL-C level (1.18 ± 0.41 mmol/L vs 1.25 ± 0.35 mmol/L, P < 0.01) than their counterparts. In addition, TC/HDL (4.19 ± 1.33 vs 3.93 ± 1.26, P < 0.01) and LDL-C/HDL-C (2.83 ± 1.10 vs 2.61 ± 0.96, P < 0.01) were higher in patients with larger tumors. The levels of HDL-C (P < 0.05), TC/HDL-C (P < 0.01) and LDL-C/HDL-C (P < 0.05) varied in different stages of CRC patients, and the differences were significant. We screened 14 differentially expressed genes (DEGs) of the cholesterol metabolism pathway in CRC and confirmed that lipoprotein receptor-related protein 8 (LRP8), PCSK9, low-density lipoprotein receptor (LDLR), MBTPS2 and FDXR are upregulated, while ABCA1 and OSBPL1A are downregulated in cancer tissue. Higher expression of LDLR (HR = 3.12, 95%CI: 1.77-5.49, P < 0.001), ABCA1 (HR = 1.66, 95%CI: 1.11-2.48, P = 0.012) and OSBPL1A (HR = 1.38, 95%CI: 1.01-1.89, P = 0.041) all yielded significantly poorer DFS outcomes. Higher expression of FDXR (HR = 0.7, 95%CI: 0.47-1.05, P = 0.002) was correlated with longer DFS. LDLR, ABCA1, OSBPL1A and FDXR were involved in many important cellular function pathways. CONCLUSION: Serum HDL-C levels are associated with tumor size and stage in CRC patients. LRP8, PCSK9, LDLR, MBTPS2 and FDXR are upregulated, while ABCA1 and OSBPL1A are downregulated in CRC. Among them, LDLR, ABCA1, OSBPL1A and FDXR were valuable prognostic factors of DFS and were involved in important cellular function pathways.

Development and Validation of a Nomogram and a Comprehensive Prognostic Analysis of an LncRNA-Associated Competitive Endogenous RNA Network Based on Immune-Related Genes for Locally Advanced Rectal Cancer With Neoadjuvant Therapy.

Colorectal cancer (CRC) is a common digestive tract tumor worldwide. In recent years, neoadjuvant chemoradiotherapy (CRT) has been the most comprehensive treatment for locally advanced rectal cancer (LARC). In this study, we explored immune infiltration in rectal cancer (RC) and identified immune-related differentially expressed genes (IRDEGs). Then, we identified response markers in datasets in GEO databases by principal component analysis (PCA). We also utilized three GEO datasets to identify the up- and downregulated response-related genes simultaneously and then identified genes shared between the PCA markers and three GEO datasets. Based on the hub IRDEGs, we identified target mRNAs and constructed a ceRNA network. Based on the ceRNA network, we explored prognostic biomarkers to develop a prognostic model for RC through Cox regression. We utilized the specimen to validate the expression of the two biomarkers. We also utilized LASSO regression to screen hub IRDEGs and built a nomogram to predict the response of LARC patients to CRT. All of the results show that the nomogram and prognostic model offer good prognostic value and that the ceRNA network can effectively highlight the regulatory relationship. hsa-mir-107 and WDFY3-AS2 may be prognostic biomarkers for RC.

Primary Tumor Resection for Rectal Cancer With Unresectable Liver Metastases: A Chance to Cut Is a Chance for Improved Survival.

Background: About half of the patients with rectal cancer will develop liver metastasis during the course of their illness. Unfortunately, a large proportion of these metastases are unresectable. Surgical resection of the primary tumor vs. palliative treatment in patients with unresectable synchronous liver metastases remains controversial. Methods: Patients with rectal cancer with surgically unresectable liver metastases were identified from the Surveillance, Epidemiology, and End Results (SEER) database from January 1, 2010, to December 31, 2015. According to different treatment modalities, patients were divided into a primary tumor resection group and a non-resection group. Rates of primary tumor resection and survival were calculated for each year. Kaplan-Meier methods and Cox regression models were used to assess long-term survival. Multivariable logistic regression models were used to evaluate factors potentially associated with primary tumor resection. Results: Among 1,957 patients, 494 (25.2%) had undergone primary tumor resection. Patients with primary tumor resection had significantly better 5-year survival rate (27.2 vs. 5.6%, P < 0.001) compared to the non-resection group. Chemoradiotherapy with primary site resection was associated with the longest mean and 5-year OS (44.7 months, 32.4%). The Cox regression analyses of the subgroup indicated that patients who underwent primary tumor resection had improved survival compared with those who did not undergo resection in all 25 subgroups. Factors associated with primary tumor resection were well or moderately differentiated tumor grade, undergoing radiation, and primary tumor size <5 cm. Conclusions: The majority of patients with rectal cancer with unresectable liver metastases did not undergo primary tumor resection. Our results indicate that resection of the primary tumor appears to offer the greatest chance of survival. Prospective studies are needed to confirm these results.

Nomograms and risk score models for predicting survival in rectal cancer patients with neoadjuvant therapy.

BACKGROUND: Colorectal cancer is a common digestive cancer worldwide. As a comprehensive treatment for locally advanced rectal cancer (LARC), neoadjuvant therapy (NT) has been increasingly used as the standard treatment for clinical stage II/III rectal cancer. However, few patients achieve a complete pathological response, and most patients require surgical resection and adjuvant therapy. Therefore, identifying risk factors and developing accurate models to predict the prognosis of LARC patients are of great clinical significance. AIM: To establish effective prognostic nomograms and risk score prediction models to predict overall survival (OS) and disease-free survival (DFS) for LARC treated with NT. METHODS: Nomograms and risk factor score prediction models were based on patients who received NT at the Cancer Hospital from 2015 to 2017. The least absolute shrinkage and selection operator regression model were utilized to screen for prognostic risk factors, which were validated by the Cox regression method. Assessment of the performance of the two prediction models was conducted using receiver operating characteristic curves, and that of the two nomograms was conducted by calculating the concordance index (C-index) and calibration curves. The results were validated in a cohort of 65 patients from 2015 to 2017. RESULTS: Seven features were significantly associated with OS and were included in the OS prediction nomogram and prediction model: Vascular_tumors_bolt, cancer nodules, yN, body mass index, matchmouth distance from the edge, nerve aggression and postoperative carcinoembryonic antigen. The nomogram showed good predictive value for OS, with a C-index of 0.91 (95%CI: 0.85, 0.97) and good calibration. In the validation cohort, the C-index was 0.69 (95%CI: 0.53, 0.84). The risk factor prediction model showed good predictive value. The areas under the curve for 3- and 5-year survival were 0.811 and 0.782. The nomogram for predicting DFS included ypTNM and nerve aggression and showed good calibration and a C-index of 0.77 (95%CI: 0.69, 0.85). In the validation cohort, the C-index was 0.71 (95%CI: 0.61, 0.81). The prediction model for DFS also had good predictive value, with an AUC for 3-year survival of 0.784 and an AUC for 5-year survival of 0.754. CONCLUSION: We established accurate nomograms and prediction models for predicting OS and DFS in patients with LARC after undergoing NT.

Differential Expression Analysis Revealing CLCA1 to Be a Prognostic and Diagnostic Biomarker for Colorectal Cancer.

Colorectal cancer (CRC) is a common malignant tumor of the digestive tract and lacks specific diagnostic markers. In this study, we utilized 10 public datasets from the NCBI Gene Expression Omnibus (NCBI-GEO) database to identify a set of significantly differentially expressed genes (DEGs) between tumor and control samples and WGCNA (Weighted Gene Co-Expression Network Analysis) to construct gene co-expression networks incorporating the DEGs from The Cancer Genome Atlas (TCGA) and then identify genes shared between the GEO datasets and key modules. Then, these genes were screened via MCC to identify 20 hub genes. We utilized regression analyses to develop a prognostic model and utilized the random forest method to validate. All hub genes had good diagnostic value for CRC, but only CLCA1 was related to prognosis. Thus, we explored the potential biological value of CLCA1. The results of gene set enrichment analysis (GSEA) and immune infiltration analysis showed that CLCA1 was closely related to tumor metabolism and immune invasion of CRC. These analysis results revealed that CLCA1 may be a candidate diagnostic and prognostic biomarker for CRC.

Impact of interval between neoadjuvant chemoradiotherapy and surgery in rectal cancer patients.

BACKGROUND: Epidemiologically, in China, locally advanced rectal cancer is a more common form of rectal cancer. Preoperative neoadjuvant concurrent chemoradiotherapy can effectively reduce the size of locally invasive tumors and improve disease-free survival (DFS) and pathologic response after surgery. At present, this modality has become the standard protocol for the treatment of locally advanced rectal cancer in many centers, but the optimal time for surgery after neoadjuvant therapy is still controversial. AIM: To investigate the impact of time interval between neoadjuvant therapy and surgery on DFS and pathologic response in patients with locally advanced rectal cancer. METHODS: A total of 231 patients who were classified as having clinical stage II or III advanced rectal cancer and underwent neoadjuvant chemoradiation followed by surgery at the National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College from November 2014 to August 2017 were involved in this retrospective cohort study. The patients were divided into two groups based on the different time intervals between neoadjuvant therapy and surgery: 139 (60.2%) patients were in group A (≤ 9 wk), and 92 (39.2%) patients were in group B (> 9 wk). DFS and pathologic response were analyzed as the primary endpoints. The secondary endpoints were postoperative complications and sphincter preservation. RESULTS: For the 231 patients included, surgery was performed at ≤ 9 wk in 139 (60.2%) patients and at > 9 wk in 92 (39.8%). The patients' clinical characteristics, surgical results, and tumor outcomes were analyzed through univariate analysis combined with multivariate regression analysis. The overall pathologic complete response (pCR) rate was 27.2% (n = 25) in the longer time interval group (> 9 wk) and 10.8% (n = 15) in the shorter time interval group (≤ 9 wk, P = 0.001). The postoperative complications did not differ between the groups (group A, 5% vs group B, 5.4%; P = 0.894). Surgical procedures for sphincter preservation were performed in 113 (48.9%) patients, which were not significantly different between the groups (group A, 52.5% vs group B, 43.5%; P = 0.179). The pCR rate was an independent factor affected by time interval (P = 0.009; odds ratio [OR] = 2.668; 95%CI: 1.276-5.578). Kaplan-Meier analysis and Cox regression analysis showed that the longer time interval (> 9 wk) was a significant independent prognostic factor for DFS (P = 0.032; OR = 2.295; 95%CI: 1.074-4.905), but the time interval was not an independent prognostic factor for overall survival (P > 0.05). CONCLUSION: A longer time interval to surgery after neoadjuvant therapy may improve the pCR rate and DFS but has little impact on postoperative complications and sphincter preservation.

Low ligation has a lower anastomotic leakage rate after rectal cancer surgery.

BACKGROUND: For laparoscopic rectal cancer surgery, the inferior mesenteric artery (IMA) can be ligated at its origin from the aorta [high ligation (HL)] or distally to the origin of the left colic artery [low ligation (LL)]. Whether different ligation levels are related to different postoperative complications, operation time, and lymph node yield remains controversial. Therefore, we designed this study to determine the effects of different ligation levels in rectal cancer surgery. AIM: To investigate the operative results following HL and LL of the IMA in rectal cancer patients. METHODS: From January 2017 to July 2019, this retrospective cohort study collected information from 462 consecutive rectal cancer patients. According to the ligation level, 235 patients were assigned to the HL group while 227 patients were assigned to the LL group. Data regarding the clinical characteristics, surgical characteristics and complications, pathological outcomes and postoperative recovery were obtained and compared between the two groups. A multivariate logistic regression analysis was performed to evaluate the possible risk factors for anastomotic leakage (AL). RESULTS: Compared to the HL group, the LL group had a significantly lower AL rate, with 6 (2.8%) cases in the LL group and 24 (11.0%) cases in the HL group (P = 0.001). The HL group also had a higher diverting stoma rate (16.5% vs 7.5%, P = 0.003). A multivariate logistic regression analysis was subsequently performed to adjust for the confounding factors and confirmed that HL (OR = 3.599; 95%CI: 1.374-9.425; P = 0.009), tumor located below the peritoneal reflection (OR = 2.751; 95%CI: 0.772-3.985; P = 0.031) and age (≥ 65 years) (OR = 2.494; 95%CI: 1.080-5.760; P = 0.032) were risk factors for AL. There were no differences in terms of patient demographics, pathological outcomes, lymph nodes harvested, blood loss, hospital stay and urinary function (P > 0.05). CONCLUSION: In rectal cancer surgery, LL should be the preferred method, as it has a lower AL and diverting stoma rate.

Corrigendum: Differential Expression Analysis Revealing CLCA1 to Be a Prognostic and Diagnostic Biomarker for Colorectal Cancer.

[This corrects the article DOI: 10.3389/fonc.2020.573295.].

Impact factors of lymph node retrieval on survival in locally advanced rectal cancer with neoadjuvant therapy.

BACKGROUND: Conventional clinical guidelines recommend that at least 12 lymph nodes should be removed during radical rectal cancer surgery to achieve accurate staging. The current application of neoadjuvant therapy has changed the number of lymph node dissection. AIM: To investigate factors affecting the number of lymph nodes dissected after neoadjuvant chemoradiotherapy in locally advanced rectal cancer and to evaluate the relationship of the total number of retrieved lymph nodes (TLN) with disease-free survival (DFS) and overall survival (OS). METHODS: A total of 231 patients with locally advanced rectal cancer from 2015 to 2017 were included in this study. According to the American Joint Committee on Cancer (AJCC)/Union for International Cancer Control (UICC) tumor-node-metastasis (TNM) classification system and the NCCN guidelines for rectal cancer, the patients were divided into two groups: group A (TLN ≥ 12, n = 177) and group B (TLN < 12, n = 54). Factors influencing lymph node retrieval were analyzed by univariate and binary logistic regression analysis. DFS and OS were evaluated by Kaplan-Meier curves and Cox regression models. RESULTS: The median number of lymph nodes dissected was 18 (range, 12-45) in group A and 8 (range, 2-11) in group B. The lymph node ratio (number of positive lymph nodes/total number of lymph nodes) (P = 0.039) and the interval between neoadjuvant therapy and radical surgery (P = 0.002) were independent factors of the TLN. However,TLN was not associated with sex, age, ASA score, clinical T or N stage, pathological T stage, tumor response grade (Dworak), downstaging, pathological complete response, radiotherapy dose, preoperative concurrent chemotherapy regimen, tumor distance from anal verge, multivisceral resection, preoperative carcinoembryonic antigen level, perineural invasion, intravascular tumor embolus or degree of differentiation. The pathological T stage (P < 0.001) and TLN (P < 0.001) were independent factors of DFS, and pathological T stage (P = 0.011) and perineural invasion (P = 0.002) were independent factors of OS. In addition, the risk of distant recurrence was greater for TLN < 12 (P = 0.009). CONCLUSION: A shorter interval to surgery after neoadjuvant chemoradiotherapy for rectal cancer under indications may cause increased number of lymph nodes harvested. Tumor shrinkage and more extensive lymph node retrieval may lead to a more favorable prognosis.

Analysis of 72 patients with colorectal high-grade neuroendocrine neoplasms from three Chinese hospitals.

BACKGROUND: Colorectal high-grade neuroendocrine neoplasms (HGNENs) are rare and constitute less than 1% of all colorectal malignancies. Based on their morphological differentiation and proliferation identity, these neoplasms present heterogeneous clinicopathologic features. Opinions regarding treatment strategies for and improvement of the clinical outcomes of these patients remain controversial. AIM: To delineate the clinicopathologic features of and explore the prognostic factors for this rare malignancy. METHODS: This observational study reviewed the data of 72 consecutive patients with colorectal HGNENs from three Chinese hospitals between 2000 and 2019. The clinicopathologic characteristics and follow-up data were carefully collected from their medical records, outpatient reexaminations, and telephone interviews. A survival analysis was conducted to evaluate their outcomes and to identify the prognostic factors for this disease. RESULTS: According to the latest recommendations for the classification and nomenclature of colorectal HGNENs, 61 (84.7%) patients in our cohort had poorly differentiated neoplasms, which were categorized as high-grade neuroendocrine carcinomas (HGNECs), and the remaining 11 (15.3%) patients had well differentiated neoplasms, which were categorized as high-grade neuroendocrine tumors (HGNETs). Most of the neoplasms (63.9%) were located at the rectum. More than half of the patients (51.4%) presented with distant metastasis at the date of diagnosis. All patients were followed for a median duration of 15.5 mo. In the entire cohort, the median survival time was 31 mo, and the 3-year and 5-year survival rates were 44.3% and 36.3%, respectively. Both the univariate and multivariate analyses demonstrated that increasing age, HGNEC type, and distant metastasis were risk factors for poor clinical outcomes. CONCLUSION: Colorectal HGNENs are rare and aggressive malignancies with poor clinical outcomes. However, patients with younger age, good morphological differentiation, and without metastatic disease can have a relatively favorable prognosis.

Intraoperative intraperitoneal chemotherapy increases the incidence of anastomotic leakage after anterior resection of rectal tumors.

BACKGROUND: Intraoperative intraperitoneal chemotherapy is an emerging treatment modality for locally advanced rectal neoplasms. However, its impacts on postoperative complications remain unknown. Anastomotic leakage (AL) is one of the most common and serious complications associated with the anterior resection of rectal tumors. Therefore, we designed this study to determine the effects of intraoperative intraperitoneal chemotherapy on AL. AIM: To investigate whether intraoperative intraperitoneal chemotherapy increases the incidence of AL after the anterior resection of rectal neoplasms. METHODS: This retrospective cohort study collected information from 477 consecutive patients who underwent an anterior resection of rectal carcinoma using the double stapling technique at our institution from September 2016 to September 2017. Based on the administration of intraoperative intraperitoneal chemotherapy or not, the patients were divided into a chemotherapy group (171 cases with intraperitoneal implantation of chemotherapy agents during the operation) or a control group (306 cases without intraoperative intraperitoneal chemotherapy). Clinicopathologic features, intraoperative treatment, and postoperative complications were recorded and analyzed to determine the effects of intraoperative intraperitoneal chemotherapy on the incidence of AL. The clinical outcomes of the two groups were also compared through survival analysis. RESULTS: The univariate analysis showed a significantly higher incidence of AL in the patients who received intraoperative intraperitoneal chemotherapy, with 13 (7.6%) cases in the chemotherapy group and 5 (1.6%) cases in the control group (P = 0.001). As for the severity of AL, the AL patients who underwent intraoperative intraperitoneal chemotherapy tended to be more severe cases, and 12 (92.3%) out of 13 AL patients in the chemotherapy group and 2 (40.0%) out of 5 AL patients in the control group required a secondary operation (P = 0.044). A multivariate analysis was subsequently performed to adjust for the confounding factors and also showed that intraoperative intraperitoneal chemotherapy increased the incidence of AL (odds ratio = 5.386; 95%CI: 1.808-16.042; P = 0.002). However, the survival analysis demonstrated that intraoperative intraperitoneal chemotherapy could also improve the disease-free survival rates for patients with locally advanced rectal cancer. CONCLUSION: Intraoperative intraperitoneal chemotherapy can improve the prognosis of patients with locally advanced rectal carcinoma, but it also increases the risk of AL following the anterior resection of rectal neoplasms.

[Potential of renewable energy development on abandoned mine areas: A case study in Liao-ning Province, Norheast China]. / 在矿山废弃地上发展可再生能源的潜力­­ä»¥è¾½å®çœä¸ºä¾‹.

Under the background of domestic and international pressure of carbon emission reduction and the requirement of energy structure adjustment, renewable energy development is under great pressure in China. Renewable energy development on abandoned mine areas has great potential due to its large area. It has great significance to develop renewable energy on abandoned mine areas for China's energy strategy. This study proposed the development scenarios of biomass energy and solar energy and estimated the development potential of renewable energy on abandoned mine areas in Liaoning Province. The results showed that the area of abandoned mine areas in Liaoning Pro-vince is 1227.6 km2, the potential of renewable energy development is large, and the potential of renewable energy in each scenario is quite different. In scenario 1, with the goal mode of maximizing the generation of photovoltaic power, the total generating capacity is 79.4 TWh, the total coal discount is 32.1 Mt standard coal, and the carbon reduction is 79.1 Mt CO2. In scenario 2, with the goal mode of maximizing biomass energy utilization, the total power generation from photovoltaic and biomass energy is 31.2-33.1 TWh, the total coal discount is 12.7-13.4 Mt standard coal, and the carbon emission reduction is 31.1-33.0 Mt CO2. In scenario 3, with the goal mode of maximizing comprehensive utilization of mine energy and consideration of ecological restoration, the total gene-rating capacity from photovoltaic and biomass energy is 62.3-63.7 TWh, the total coal discount is 25.1-25.7 Mt standard coal, and the carbon emission reduction is 62.1-63.5 Mt CO2. Under the three scenarios, the generation capacity range of is 31.2-79.4 TWh, accounting for 15.3%-38.9% of the total power consumption in Liaoning Province in 2016, which could be converted into 12.7-32.1 Mt standard coal, and contribute to a reduction of 31.1-79.1 Mt CO2 emission. The calculations of new energy development potential on abandoned mine areas and quantification of its capacity of alternatives to fossil energy will be helpful for carbon emission reduction, energy structure adjustment, and the recovery of the mining ecosystem.

[Dynamic changes of forest landscape pattern in Lushuihe Forest Bureau of Changbai Mountains, northeast China].

Based on the forest management inventories in Lushihe Forest Bureau of Changbai Mountains in 1987, 1995 and 2003, and by using ArcGIS and Fragstats spatial analysis software, this paper analyzed the relationships between landscape pattern change and forest management mechanism in the study area at landscape and patch scales. During the study period, the landscape fragmentation degree and heterogeneity in the study area increased. From 1987 to 2003, the patch number increased by 979, while the proportion of the largest patch area decreased from 28. 7% to 12.7%. With the change of management strategy, the landscape matrix changed from mixed broad-leaved forest matrix in 1987 to compound matrix in 1995. The extent of landscape fragmentation in 1995-2003 was somewhat reduced, compared with that in 1987-1995. During the study period, the mean patch area and edge density of broadleaved mixed forest decreased most, suggesting that natural secondary forest suffered most from human disturbances.

[Magnifying effect of conduit bridging in number of nerve fibers of broken peripheral nerves: experiment with rats].

OBJECTIVE: To observe the magnifying effect of conduit bridging in number of nerve fibers of broken peripheral nerves. METHODS: Fifty Sprague-Dawley rats were randomly divided into five equal groups. Group A underwent transection of the sciatic nerves and bridging of the complete proximal sciatic nerve stump and the distal sciatic stump in a conduit sutured with 8 - 0 nylon chord with a 2-mm gap. In Group B, the sciatic nerve was transected, the proximal stump was divided into tibial nerve and common peroneal nerve bundles 5 mm proximal to the transection site, the common peroneal nerve bundle was ligated and transected, and then the proximal stump of the tibial nerve and the distal sciatic stump were bridged with a conduit with a 2-mm gap. In Group C, the sciatic nerve was transected, the proximal stump was divided into tibial nerve and common peroneal nerve bundles 10 mm proximal to the transection site, the tibial nerve bundle was ligated and transected, and then the proximal stump of the common peroneal nerve and the distal sciatic stump were bridged with a conduit with a 2-mm gap. In group D, the tibial nerve was transected 5 mm distal to the branch site, 2/3 of the tibial nerve fibers were ligated and transected, and then the remnant 1/3 fibers of the proximal stump of tibial nerve were bridged to the distal stump of tibial in a conduit. In Group E the tibial nerve was transected 5 mm distal to the branch site, and then the complete proximal tibial nerve stump was bridged to the distal stump of tibial nerve in a conduit Electrophysiological examination was conducted 1, 2, 4, and 12 weeks later. Pathological examination was performed with immunohistochemistry, HE staining and osmic acid staining. RESULTS: One week after surgery, edema and ulcer in the hind limbs were found in most rats; toe necrosis was seen in part of the rats, and since 3 weeks later these pathological changes began to disappear gradually. The motion of hind limbs recovered since 4 weeks after the surgery. Osmic acid staining 12 weeks later showed that the numbers of distal myelin sheath at the distal end were more than that in the proximal end by 34.4% in Group A, 39.6% in Group B, 80.4% in Group C, 101.1% in Group D, and 48.9% in Group E. CONCLUSION: The axon number distal to the transaction site becomes significantly more than that at the proximal end after bridging. The magnification effect of the bridging of homologous nerve is greater than that of non-homologous nerve. It is possible to repair the thicker nerve at the distal broken end with thinner nerve at the proximal end clinically.

[The rule of proliferation after sciatic injury of rats: immunohistological observation].

OBJECTIVE: To describe the rule of the schwann cell proliferation after peripheral nerve injury in detail and to discover the effect of neuroanastomosis. METHODS: The model of rat sciatic injury was made, with neuroanastomosis on the left side and right side untreated. Then draw the materials 24, 48 h, 4, 7, 14, 21 d after surgery. And immunohistological stain counted the schwann cell per view with Qwin software of Leica Ltd. RESULTS: The number of schwann cell increased obviously 4 d after surgery and reached the peak in 7 d. Then it fell down and the neuroanastomosis group changed slower and fibroblast hyperplasia in the untreated. CONCLUSIONS: The axon support is essential for the schwann cell. The precise rule is help for study on neurotrophic factor.

Study on the adoption of Schwann cell phenotype by bone marrow stromal cells in vitro and in vivo.

OBJECTIVE: To explore the possibilities of bone marrow stromal cells (MSCs) to adopt Schwann cell phenotype in vitro and in vivo in SD rats. METHODS: MSCs were obtained from tibia and femur bone marrow and cultured in culture flasks. Beta-mercaptoethanol followed by retinoic acid, forskolin, basic-FGF, PDGF and heregulin were added to induce differentiation of MSCs'. Schwann cell markers, p75, S-100 and GFAP were used to discriminate induced properties of MSCs' by immunofluorescent staining. PKH-67-labelled MSCs were transplanted into the mechanically injured rat sciatic nerve, and laser confocal microscopy was performed to localize the PKH67 labelled MSCs in the injured sciatic nerve two weeks after the operation. Fluorescence PKH67 attenuation rule was evaluated by flow cytometry in vitro. RESULTS: MSCs changed morphologically into cells resembling primary cultured Schwann cells after their induction in vitro. In vivo, a large number of MSCs were cumulated within the layer of epineurium around the injured nerve and expressed Schwann cell markers, p75, S-100, and GFAP. CONCLUSION: MSCs are able to support nerve fiber regeneration and re-myelination by taking on Schwann cell function, and can be potentially used as possible substitutable cells for artificial nerve conduits to promote nerve regeneration.