[Distribution and Influencing Factors of DOM Components in Urban and Suburban Polluted Rivers].

Dissolved organic matter(DOM) in water environments is an important component of the global carbon cycle. Under the current urgency to control the pollution of urban rivers in China, exploring the influence of different exogenous and endogenous secondary pollution and weather patterns on river DOM is the premise to better understand the causes of the pollution. In this study, a large city in China was established as the research area, and the underlying water and sediments from 21 sites along urban and suburban rivers, and other water sources were evaluated. The excitation-emission matrix-parallel factor analysis(EEM-PARAFAC) was used to analyze the difference in DOM composition and equivalent in urban rivers polluted by domestic sewage and suburban rivers polluted by aquaculture, agriculture, and livestock breeding. The results showed that:① DOM components in urban and suburban river waters were mainly protein compounds(tyrosine-and tryptophan-like), containing a small amount of humic acid. Humic acid components of anthropogenic origin were found in urban river water; ② The reasons for the formation of DOM components in urban and suburban rivers were completely different. Urban rivers are mainly polluted by domestic sewage and endogenous secondary pollution, resulting in an increase in anthropogenic humic acid components. Suburban rivers are mainly polluted by agricultural wastewater rich in N and P, which promotes endogenous metabolism of autotrophic bacteria and increases protein components, which may be related to the formation of existing DOM characteristics. ③ Rainfall runoff and urban overflow transported exogenous pollutants into rivers, while hydrodynamic factors such as hydraulic agitation affect the distribution of DOM components in underlying water and sediments through physical effects such as dilution.

Combined gastroscopic and choledochoscopic transabdominal nasobiliary drainage.

Common bile duct (CBD) stones are a frequent problem in Chinese populations, and their incidence is particularly high in certain areas (Wang et al., 2013). In recent years, laparoscopic common bile duct exploration (LCBDE) and endoscopic retrograde cholangiopancreatography (ERCP) have been the main surgical procedures for CBD stones, although each has different advantages and disadvantages in the treatment of choledocholithiasis (Loor et al., 2017; Zhou et al., 2017). For patients with large stones, a dilated CBD, especially concurrent gallstones, LCBDE is the preferred and most economical minimally invasive procedure (Koc et al., 2013). However, a T-tube is often placed during LCBDE to prevent postoperative bile leakage; this is associated with problems such as bile loss, electrolyte disturbance, and decreased gastric intake (Martin et al., 1998). In addition, the T-tube usually must remain in place for more than a month, during which time the patient's quality of life is seriously compromised. Many skilled surgeons currently perform primary closure of the CBD following LCBDE, which effectively speeds up rehabilitation (Hua et al., 2015). However, even in sophisticated medical centers, the incidence of postoperative bile leakage still reaches ≥10% (Liu et al., 2017). Especially for a beginner, bile leakage remains a key problem (Kemp Bohan et al., 2017). Therefore, a safe and effective minimally invasive surgical approach to preventing bile leakage during primary closure of the CBD after LCBDE is still urgently needed.

SET Domain-Containing Protein 4 Epigenetically Controls Breast Cancer Stem Cell Quiescence.

Quiescent cancer stem cells (CSC) play important roles in tumorigenesis, relapse, and resistance to chemoradiotherapy. However, the determinants of CSC quiescence and how they sustain themselves to generate tumors and relapse beyond resistance to chemoradiotherapy remains unclear. Here, we found that SET domain-containing protein 4 (SETD4) epigenetically controls breast CSC (BCSC) quiescence by facilitating heterochromatin formation via H4K20me3 catalysis. H4K20me3 localized to the promoter regions and regulated the expression of a set of genes in quiescent BCSCs (qBCSC). SETD4-defined qBCSCs were resistant to chemoradiotherapy and promoted tumor relapse in a mouse model. Upon activation, a SETD4-defined qBCSC sustained itself in a quiescent state by asymmetric division and concurrently produced an active daughter cell that proliferated to produce a cancer cell population. Single-cell sequence analysis indicated that SETD4+ qBCSCs clustered together as a distinct cell type within the heterogeneous BCSC population. SETD4-defined quiescent CSCs were present in multiple cancer types including gastric, cervical, ovarian, liver, and lung cancers and were resistant to chemotherapy. SETD4-defined qBCSCs had a high tumorigenesis potential and correlated with malignancy and chemotherapy resistance in clinical breast cancer patients. Taken together, the results from our previous study and current study on six cancer types reveal an evolutionarily conserved mechanism of cellular quiescence epigenetically controlled by SETD4. Our findings provide insights into the mechanism of tumorigenesis and relapse promoted by SETD4-defined quiescent CSCs and have broad implications for clinical therapies. SIGNIFICANCE: These findings advance our knowledge on the epigenetic determinants of quiescence in cancer stem cell populations and pave the way for future pharmacologic developments aimed at targeting drug-resistant quiescent stem cells.

Prognostic value of programmed cell death protein 1 expression on CD8+ T lymphocytes in pancreatic cancer.

Pancreatic cancer is one of the most aggressive malignancies and has a highly immunosuppressive tumour microenvironment. Immune checkpoint blockade has led to remarkable and durable objective responses in a number of malignancies and antibody-based strategies targeting programmed cell death protein 1 (PD-1) are showing promise where traditional modalities of surgery, radiotherapy, and chemotherapy have failed. In this study, we examined the clinical value of PD-1 protein expression by CD8+ peripheral T lymphocytes or tumour-infiltrating T lymphocytes (TILs) in pancreatic ductal adenocarcinoma (PDAC). Expression of PD-1 protein on CD8+ TILs correlated with overall survival and clinicopathological characteristics such as clinical stage, N classification, and M classification. Similar findings were observed for the expression of PD-1 protein on peripheral CD8+ T cells, whereas its expression on peripheral CD4+ T cells showed no significance. Comparison of the levels of PD-1 protein expressed by peripheral CD8+ T cells before and 4 weeks after surgery indicated that preoperative and postoperative status of peripheral PD-1 expression was unchanged. Our findings showed that PD-1 protein expressed by peripheral or tumour-infiltrated CD8+ T cells was a promising biomarker for diagnosis and prognosis in PDAC and might help guide future immunotherapies.

Cholangiocarcinoma-derived exosomes inhibit the antitumor activity of cytokine-induced killer cells by down-regulating the secretion of tumor necrosis factor-α and perforin.

OBJECTIVE: The aim of our study is to observe the impact of cholangiocarcinoma-derived exosomes on the antitumor activities of cytokine-induced killer (CIK) cells and then demonstrate the appropriate mechanism. METHODS: Tumor-derived exosomes (TEXs), which are derived from RBE cells (human cholangiocarcinoma line), were collected by ultracentrifugation. CIK cells induced from peripheral blood were stimulated by TEXs. Fluorescence-activated cell sorting (FACS) was performed to determine the phenotypes of TEX-CIK and N-CIK (normal CIK) cells. The concentrations of tumor necrosis factor-α (TNF-α) and perforin in the culture medium supernatant were examined by using an enzyme-linked immunosorbent assay (ELISA) kit. A CCK-8 kit was used to evaluate the cytotoxic activity of the CIK cells to the RBE cell line. RESULTS: The concentrations of TNF-α and perforin of the group TEX-CIK were 138.61 pg/ml and 2.41 ng/ml, respectively, lower than those of the group N-CIK 194.08 pg/ml (P<0.01) and 3.39 ng/ml (P<0.05). The killing rate of the group TEX-CIK was 33.35%, lower than that of the group N-CIK (47.35% (P<0.01)). The population of CD3(+), CD8(+), NK (CD56(+)), and CD3(+)CD56(+) cells decreased in the TEX-CIK group ((63.2±6.8)%, (2.5±1.0)%, (0.53±0.49)%, (0.45±0.42)%) compared with the N-CIK group ((90.3±7.3)%, (65.7±3.3)%, (4.2±1.2)%, (15.2±2.7)%), P<0.01. CONCLUSIONS: Our results suggest that RBE cells-derived exosomes inhibit the antitumor activity of CIK cells by down-regulating the population of CD3(+), CD8(+), NK (CD56(+)), and CD3(+)CD56(+) cells and the secretion of TNF-α and perforin. TEX may play an important role in cholangiocarcinoma immune escape.

Increasing the immune activity of exosomes: the effect of miRNA-depleted exosome proteins on activating dendritic cell/cytokine-induced killer cells against pancreatic cancer.

BACKGROUND: Tumor-derived exosomes were considered to be potential candidates for tumor vaccines because they are abundant in immune-regulating proteins, whereas tumor exosomal miRNAs may induce immune tolerance, thereby having an opposite immune function. OBJECTIVE: This study was designed to separate exosomal protein and depleted exosomal microRNAs (miRNAs), increasing the immune activity of exosomes for activating dendritic cell/cytokine-induced killer cells (DC/CIKs) against pancreatic cancer (PC). METHODS: PC-derived exosomes (PEs) were extracted from cultured PANC-1 cell supernatants and then ruptured; this was followed by ultrafiltered exosome lysates (UELs). DCs were stimulated with lipopolysaccharide (LPS), PE, and UEL, followed by co-culture with CIKs. The anti-tumor effects of DC/CIKs against PC were evaluated by proliferation and killing rates, tumor necrosis factor-α (TNF-α) and perforin secretion. Exosomal miRNAs were depleted after lysis and ultrafiltration, while 128 proteins were retained, including several immune-activating proteins. RESULTS: UEL-stimulated DC/CIKs showed a higher killing rate than LPS- and PE-stimulated DC/CIKs. CONCLUSIONS: miRNA-depleted exosome proteins may be promising agonists for specifically activating DC/CIKs against PC.

Management of giant ovarian teratoma: A case series and review of the literature.

The management of ovarian teratomas in normal conditions is well established, but in rare giant cases (tumor diameter over 15 cm), the choice of management, such as laparotomic or laparoscopic approaches, are controversial and may be therapeutically challenging for surgeons. The aims of the current study were to analyze the clinical features of giant ovarian teratoma and to discuss its management. The clinical data of 330 patients with giant ovarian teratoma (of whom 1 patient was treated by the authors and 329 were admitted to the Second Affiliated Hospital of Zhejiang University Medical College between January 1st 2000 and December 31st 2010) were reviewed and analyzed. The patients had an age range of 6 to 83 years and a mean tumor size of 24.9±7.1 cm. Of the 330 patients, 102 (30.9%) were asymptomatic and the majority (69.1%, 228/330) reported symptoms. There were more patients in the laparotomic group than the laparoscopic group, especially for the emergency cases (5.5 vs. 0%, P<0.05). Accidental cyst rupture was more frequent when a laparoscopic approach was used (31.5 vs. 19.6%, P<0.05). These results suggest that laparotomic resection may be preferred for the en bloc mass removal, adequate abdominal cavity irrigation and avoidance of accidental mass rupture in the management of giant ovarian teratomas. Familiarity with the imaging features of giant ovarian teratomas effectively aids preoperative diagnosis and differentiation.

Saline conducted electric coagulation (SCEC): original experience in experimental hepatectomy.

OBJECTIVE: To evaluate the feasibility and superiority of a new coagulating and hemostatic method named "saline conducted electric coagulation (SCEC)". METHODS: The Peng's multifunction operative dissector (PMOD) was modified to enable saline to effuse persistently out of its nib at a constant speed. In a group of six New Zealand rabbits, two hepatic lobes of each rabbits were resected respectively by SCEC and conventional electric coagulation (EC). The features of SCEC were recorded by photo and compared with conventional EC. After 7 d, the coagulating depth was measured in each residual hepatic lobe. Hepatic tissue was dyed by hematoxylin and eosin (HE) and studied under a microscope. RESULTS: The coagulating depth increased with the continuation of SCEC time. Hepatectomies were performed successfully, no rabbit died in the perioperative period. The incisal surface of SCEC was gray-white with no red bleeding point. There was a thick solidified layer at the margin and a thin red-white intermittent layer between the solidified layer and normal hepatic tissue at the vertical section of SCEC. The mean coagulating depth of SCEC was 1.8 cm vs. 0.3 cm of conventional EC. Pathological examination showed a mild inflammatory reaction by SCEC. CONCLUSIONS: SCEC is a feasible and safe method for surgical hemostasis. As a new technique for liver resection, SCEC shows better coagulating effect and milder inflammatory reaction than conventional EC. Our study shows bloodless liver resection can also be performed by SCEC, especially for liver malignant tumor.

Transumbilical single-port laparoscopic cholecystectomy using traditional laparoscopic instruments: a report of thirty-six cases.

OBJECTIVE: To evaluate the feasibility and safety of the operation of transumbilical single-port laparoscopic cholecystectomy (TSPLC) by traditional laparoscopic instruments and summarize the initial experience. METHODS: Sixty subjects with cholelithiasis were divided into two groups. One group (36 cases) underwent TSPLC and the control group (24 cases) underwent traditional three-port laparoscopic cholecystectomy (LC). Postoperative complications were observed and operation time, hospital days, visual analogue scale (VAS) after 6 and 24 h of operation, and subject satisfaction score were measured. RESULTS: TSPLC and traditional LC were performed successfully in the two groups. The operation time in the TSPLC group was significantly longer than that in the control group. There was no statistically significant difference in hospital stay and VAS between the TSPLC and control groups. The subject satisfaction score in the TSPLC group was 91.2, significantly higher than that in the control group (P<0.01). All subjects recovered from the operation and no postoperative complication occurred during the period of two weeks after operation. CONCLUSIONS: TSPLC is a feasible and safe method for cholecystectomy, although it may be more time-consuming. However, it is welcomed by patients who are more concerned with cosmetic outcomes. Future studies are needed to confirm its disadvantages and contraindications.

Assessment of ¹88Re marked anti MHC class II antibody by peripheral blood mononuclear cells stimulated by donor alloantigen.

BACKGROUND: Previous studies showed that anti MHC-II monoclone antibody (MAb) only had partial inhibiting effect of alloreactive mixed lymphocyte reaction (MLR) in vitro and it was unsteady and non-persistent. The aim of this research was to determine whether radioactive isotope (188)Re marked MHC-II antibody could benefit the allograft acceptance in transplantation as compared to normal MHC-II antibody. METHODS: 188Re was incorporated to 2E9/13F (ab')(2) which is against swine MHC class II antigen (MAb-(188)Re). Porcine peripheral blood mononuclear (PBMC) cells were examined for proliferation and cytokine mRNA expression after stimulation with MHC-II MAb or MAb-(188)Re. RESULTS: The proliferative response of recipient PBMCs in mixed lymphocyte reaction (MLR) to donor alloantigen showed that the stimulation index of MAb-(188)Re group was significantly lower than the MHC-II MAb group and control (P < 0.05). mRNA expression of interleukin 2, interferon Υ and tumor necrosis factor α (type 1 cytokines) was lower in MAb-(188)Re group than the MHC-II MAb group, while interleukin 10 (type 2 cytokines) was higher in MAb-(188)Re group in the first 24 hours. CONCLUSION: MAb-(188)Re could help the graft acceptance by inhibiting T cell proliferation, lowering the expression of type 1 cytokines and elevating the type 2 cytokines produced by PBMC.

Correlation of nitric oxide and other free radicals with the severity of acute pancreatitis and complicated systemic inflammatory response syndrome.

OBJECTIVES: To investigate the correlation of nitric oxide (NO) and other free radicals with the severity of acute pancreatitis (AP) and complicated systemic inflammatory response syndrome (SIRS). METHODS: Fifty AP patients (24 simple AP patients and 26 patients with AP complicated by SIRS) were involved in the study. Fifty healthy volunteers were included as controls. Acute Physiology and Chronic Health Evaluation II (APACHE II) scores were evaluated, and plasma NO, plasma lipid peroxides, plasma vitamin E, plasma beta-carotene, whole-blood glutathione (GSH), and the activity of plasma GSH peroxidase were measured. RESULTS: Compared with the control group, the APACHE II scores heightened in the AP group, and the SIRS group had the highest APACHE II scores (P < 0.005, P < 0.001, respectively). Plasma NO and plasma lipid peroxides increased with the heightening APACHE II scores, demonstrating a significant linear positive correlation (r = 0.618, r = 0.577, respectively; P < 0.001). Plasma vitamin E, plasma beta-carotene, whole-blood GSH, and the activity of plasma GSH peroxidase decreased with the heightening APACHE II scores, demonstrating a significant linear negative correlation (r = -0.600, r = -0.609, r = -0.559, r = -0.592, respectively; P < 0.001). CONCLUSIONS: Nitric oxide and other free radicals take part in the aggravation of oxidative stress and oxidative injury and may play important roles in the pathogenesis of AP and SIRS. It may be valuable to measure free radicals to predict the severity of AP.

[Roles of nutrition risk screening and preventive enteral nutritional support before radical resection of gastric cancer].

OBJECTIVE: To investigate the potential role of the preventive nutritional support in patients with nutritional risk defined by nutrition risk screening 2002(NRS 2002) before radical resection of gastric cancer. METHODS: Patients with gastric cancer were evaluated by NRS 2002 preoperatively. Elective patients with nutritional risk were randomly assigned into 3 d preventive enteral nutrition(EN) group versus control group. The preventive nutrition regimen was 1000 ml Nutrison Multi Fibre(4184 kJ/L). The changes in body weight lost, serum albumin, immunoglobulin were recorded postoperatively. RESULTS: One week after operation, the preventive EN group showed less decrease in body weight as compared to control group, which was statistically significant. The levels of serum albumin and IgA on day 1 and day 3 after operation in preventive EN group were significantly higher than those in control group. CONCLUSION: Before operation for gastric cancer, patients with nutritional risk defined by NRS 2002 may benefit from preventive enteral nutrition, which improves the patients' nutritional condition and enhances their immunologic function.

[Research on telerobotic laparoscopic surgery and its applications].

A general review is here presented on the development, composition, existing problems and prospects of telerobotic laparoscopic surgery systems, based on the related literatures and informations in recent years.

Influence of CO2 pneumoperitoneum on intracellular pH and signal transduction in cancer cells.

OBJECT: The authors studied the influence of CO(2) pneumoperitoneum on intracellular pH and signal transduction arising from cancer cell multiplication in laparoscopic tumor operation. METHOD: They set up a simulation of pneumoperitoneum under different CO(2) pressure, and then measured the variation of intracellular pH (pHi) at different time and the activity of protein kinase C (PKC) and protein phosphatase 2a (PP2a) at the end of the pneumoperitoneum. After 1 week, the concentration of cancer cells in the culture medium was calculated. RESULT: When the pressure of CO(2) pneumoperitoneum was 0, 10, 20, 30 mmHg respectively, the average pHi was 7.273, 7.075, 6.783, 6.693 at the end of the pneumoperitoneum; PKC activity was 159.4, 168.5, 178.0, 181.6 nmol/(g.min) and PP2a was 4158.3, 4066.9, 3984.0, 3878.5 nmol/(g.min) respectively. After 1 week, the cancer cells concentration was 2.15 x 10(5), 2.03 x 10(5), 2.20 x 10(5), 2.18 x 10(5) L(-1). CONCLUSION: CO(2) pneumoperitoneum could promote acidosis in cancer cells, inducing the activation of protein kinase C and deactivation of protein phosphatase 2a, but it could not accelerate the mitosis rate of the cancer cells.