Thermal Oxidative Aging and Service Life Prediction of Commercial Ethylene-Propylene-Diene Monomer Spacer Damping Composites for High-Voltage Transmission Lines.

The aging behavior and life prediction of rubber composites are crucial for ensuring high-voltage transmission line safety. In this study, commercially available ethylene-propylene-diene monomer (EPDM) spacer composites were chosen and investigated to elucidate the structure and performance changes under various aging conditions. The results showed an increased C=O peak intensity with increasing aging time, suggesting intensified oxidation of ethylene and propylene units. Furthermore, the surface morphology of commercial EPDM composites displayed increased roughness and aggregation after aging. Furthermore, hardness, modulus at 100% elongation, and tensile strength of commercial EPDM composites exhibited a general increase, while elongation at break decreased. Additionally, the damping performance decreased significantly after aging, with a 20.6% reduction in loss factor (20 °C) after aging at 100 °C for 672 h. With increasing aging time and temperature, the compression set gradually rose due to the irreversible movement of the rubber chains under stress. A life prediction model was developed based on a compression set to estimate the lifetime of rubber composites for spacer bars. The results showed that the product's life was 8.4 years at 20 °C. Therefore, the establishment of a life prediction model for rubber composites can provide valuable technical support for spacer product services.

Effects of resveratrol and its derivative pterostilbene on hepatic injury and immunological stress of weaned piglets challenged with lipopolysaccharide.

The present study was to investigate the protective effects of resveratrol (RSV) and its 3,5-dimethylether derivative pterostilbene (PT) against liver injury and immunological stress of weaned piglets upon lipopolysaccharide (LPS) challenge. Seventy-two weaned piglets were divided into the following groups: control group, LPS-challenged group, and LPS-challenged groups pretreated with either RSV or PT for 14 d (n = 6 pens, three pigs per pen). At the end of the feeding trial, piglets were intraperitoneally injected with either LPS or an equivalent amount of sterile saline. After 6 h of sterile saline or LPS injection, plasma and liver samples were collected. LPS stimulation caused massive apoptosis, activated inflammatory responses, and incited severe oxidative stress in the piglet livers while also promoting the nuclear translocation of nuclear factor kappa B (NF-κB) p65 (P < 0.001) and the protein expression of Nod-like receptor pyrin domain containing 3 (NLRP3; P = 0.001) and cleaved caspase 1 (P < 0.001). PT was more effective than RSV in alleviating LPS-induced hepatic damage by decreasing the apoptotic rate of liver cells (P = 0.045), inhibiting the transcriptional expression of interleukin 1 beta (P < 0.001) and interleukin 6 (P = 0.008), and reducing myeloperoxidase activity (P = 0.010). The LPS-induced increase in hepatic lipid peroxidation accumulation was also reversed by PT (P = 0.024). Importantly, inhibiting protein phosphatase 2A (PP2A) activity in a hepatocellular model largely blocked the ability of PT to prevent tumor necrosis factor alpha-induced increases in NF-κB p65 protein phosphorylation (P = 0.043) and its nuclear translocation (P = 0.029). In summary, PT is a promising agent that may alleviate liver injury and immunological stress of weaned piglets via the PP2A/NF-κB/NLRP3 signaling pathway.

Intensive swine production increases the exposure risk of piglets to immunological stress that disrupts hepatic functionality, leading to inferior disease resistance and compromised growth performance. Therefore, it is imperative to seek appropriate nutrients with protective potential to alleviate liver injury of young piglets under the conditions of immunological stress. The objective of this study was to investigate the potential of resveratrol and its derivative pterostilbene (PT) to protect the liver from lipopolysaccharide (LPS)-induced immunological stress and inflammatory damage in weaned piglets. In the animal study, PT exhibited significantly better efficacy than its parent compound in alleviating LPS-induced hepatic damage, probably by inhibiting nuclear factor kappa B (NF-κB) p65 nuclear translocation, Nod-like receptor pyrin domain containing 3 (NLRP3) and cleaved caspase-1 protein expression, and proinflammatory mediator overproduction. Under cell culture condition, inhibiting protein phosphatase 2A (PP2A), a negative regulator of the NF-κB signaling pathway, largely blocked the ability of PT to prevent NF-κB activation, indicating that PT may inhibit NF-κB signals in a PP2A-dependent manner. This study provides novel evidence that PT could serve as a hepatoprotective agent to alleviate hepatic damage and immunological stress in LPS-challenged piglets.

The tumor immune microenvironment transcriptomic subtypes of colorectal cancer for prognosis and development of precise immunotherapy.

BACKGROUND: Biomarkers based on immune context may guide prognosis prediction. T-cell inactivation, exclusion, or dysfunction could cause unfavorable tumor microenvironments, which affect immunotherapy and prognosis. However, none of the immuno-biomarkers reported to date can differentiate colorectal-cancer (CRC) patients. Thus, we aimed to classify CRC patients according to the levels of T-cell activation, exclusion, and dysfunction in the tumor microenvironment. METHODS: RNAseq data of 618 CRC patients from The Cancer Genome Atlas and microarray data of 316 CRC patients from Gene Expression Omnibus were analysed using the Tumor Immune Dysfunction and Exclusion algorithm. Unsupervised clustering was used to classify patients. RESULTS: Based on the expression signatures of myeloid-derived suppressor cells, cancer-associated fibroblasts, M2-like tumor-associated macrophages, cytotoxic T-lymphocytes, and PD-L1, all patients were clustered into four subtypes: cluster 1 had a high level of immune dysfunction, cluster 2 had a low level of immune activation, cluster 3 had intense immune exclusion, and cluster 4 had a high level of immune activation and a moderate level of both dysfunction and exclusion signatures. Compared with cluster 1, the hazard ratios and 95% confidential intervals for overall survival were 0.63 (0.35-1.13) for cluster 2, 0.55 (0.29-1.03) for cluster 3, and 0.30 (0.14-0.64) for cluster 4 in multivariate Cox regression. Similar immune clustering and prognosis patterns were obtained upon validation in the GSE39582 cohort. In subgroup analysis, immune clustering was significantly associated with overall survival among stage I/II patients, microsatellite stable/instability-low patients, and patients not treated with adjuvant therapy. CONCLUSIONS: Our findings demonstrated that classifying CRC patients into different immune subtypes serves as a reliable prognosis predictor and may help to refine patient selection for personalized cancer immunotherapy.

Risk factors analysis for surgical site infection following elective colorectal resection: a retrospective regression analysis.

BACKGROUND: A surgical site infection (SSI) is a major post-operative complication from elective colorectal surgery; however, few studies have focused on evaluating the risk factors for SSI. This study aimed to analyze the relative correlation of medical and environmental factors as well as patient-related factors that contribute to the incidence of all types of SSI. METHODS: A retrospective search for eligible patients was conducted using the patient database of the Gastrointestinal Surgery Center of the Third Affiliated Hospital of Sun Yat-sen University from January 2011 to August 2017. Pre-operative demographic and surgical data were extracted and recoded according to the study protocol. Univariate and multivariate analyses were performed to clarify factors affecting the incidence of SSI. Propensity analysis was conducted to minimize bias in the demographic characteristics to explore the prophylactic effect of pre-operative administration of oral antibiotics. RESULTS: Univariate analysis of the baseline characteristics revealed that younger age (odds ratio [OR]: 0.378; 95% confidence interval [CI]: 0.218-0.657) and pre-operative oral antibiotic use (OR: 0.465; 95% CI: 0.255-0.850) were protective factors, while pre-operative anemia (OR: 4.591; 95% CI: 2.567-8.211), neoadjuvant chemotherapy history (OR: 2.398; 95% CI: 1.094-5.256), and longer surgical duration (OR: 2.393; 95% CI: 1.349-4.246; P = 0.002) were identified as risk factors for SSI. Multivariate analysis indicated that age (P = 0.003), surgical duration (P = 0.001), and pre-operative oral antibiotic use (P < 0.001) were independent factors that affect the incidence of SSI. Furthermore, a propensity-matched analysis confirmed the protective effect of oral antibiotic use, with a 1-day course of oral antibiotic producing a similar effect to a 3-day course. CONCLUSIONS: Age, surgical duration, and pre-operative oral antibiotic use were associated with the incidence of SSI. However, pre-operative oral antibiotic use was the only controllable factor. From the results of our study, pre-operative oral antibiotic use is recommended before elective colorectal surgery and a 1-day course is enough to provide the protective effect.

Transcriptome sequencing analysis of porcine MDM response to FSL-1 stimulation.

Mycoplasma infection can cause many diseases in pigs, resulting in great economic losses in pork production. Innate immune responses are thought to play critical roles in the pathogenesis of mycoplasma disease. However, the molecular events involved in immune responses remain to be determined. Hence, the object of this study was to use RNA-Seq to investigate the gene expression profiles of the innate immune response mediated by FSL-1 in pig monocyte-derived macrophages (MDMs). The results revealed that 1442 genes were differentially expressed in the FSL-1 group compared with the control groups, of which 777 genes were upregulated and 665 genes were downregulated. KEGG pathway analysis showed that the upregulated genes were mainly involved in innate immune-related pathways including the TNF signaling pathway, cytokine-cytokine receptor interaction, Toll-like receptor signaling pathway, Jak-STAT signaling pathway, chemokine signaling pathway, NOD-like receptor signaling pathway and NF-kappa B signaling pathway. The downregulated genes were only involved in the cGMP-PKG signaling pathway and glycerophospholipid metabolism. Our results showed that FSL-1 stimulation activated the TLR2 signaling pathway and resulted in diverse inflammatory responses. FSL-1 induced the transcription of numerous protein-coding genes involved in a complex network of innate immune-related pathways. We speculate that TNF, IL1B, IL6, NFKB1, NFKBIA, CXCL2, CXCL8, CXCL10, CCL2, CCL4 and CCL5 were the most likely hub genes that play important roles in the above pathways. This study identified the differentially expressed genes and their related signaling pathways, contributing to the comprehensive understanding of the mechanisms underlying host-pathogen interactions during mycoplasma infection and providing a reference model for further studies.

Predictive models of adjuvant chemotherapy for patients with stage ii colorectal cancer: A retrospective study.

BACKGROUND: It remains controversial whether patients with Stage II colorectal cancer would benefit from adjuvant chemotherapy after radical resection. The aim of this study was to establish two mathematical models to identify the suitable patients for adjuvant chemotherapy. METHODS: The current study comprised of two steps. In the first step, 353 patients with Stage II colorectal cancer who underwent surgical procedures at the Third Affiliated Hospital of Sun Yat-sen University between June 2006 and December 2015 were entered and followed up for 6-120 months. Their clinical data were collected and enrolled into the database. We established two mathematical models by univariate and multivariate Cox regression analysis to identify the target patients; in the second step, 230 patients under the same standard between January 2012 and December 2016 were entered and followed up for 3-62 months to verify the two models' validation. RESULTS: In the first step, totally 340 surgical patients with Stage II colorectal cancer were finally enrolled in this study. Statistical analysis showed that tumor differentiation (TD) (P < 0.001), lymphovascular invasion (LVI) (P < 0.001), uncertain or positive margins (UPM) (P < 0.001), and fewer lymph nodes (LNs) (<12) retrieved (P < 0.001) were correlated with the overall survival (OS) and disease free survival (DFS). We obtained two models: (1) OS risk score = 1.116 × TD + 2.202 × LVI + 3.676 × UPM + 1.438 × LN - 0.493; (2) DFS risk score = 0.789 × TD + 2.074 × LVI + 3.183 × UPM + 1.329 × LN - 0.432. According to the models and cutoff points [(0.07, 1.33) and (-0.04, 1.30), respectively], patients can be divided into three groups: low-risk, moderate-risk, and high-risk. Moreover, the high-risk group patients could benefit from adjuvant chemotherapy. In the second step, totally 221 patients were finally used to verify the models' validation. The results proved that the models were accurate and feasible (P< 0.05). CONCLUSIONS: According to the predictive models, patients with Stage II colorectal cancer in the high-risk group are strongly recommended for adjuvant chemotherapy, thus facilitating the individualized and precise treatment.

Endoscopy-Assisted Laparoscopic Resections for Gastric Gastrointestinal Stromal Tumors: A Retrospective Study.

OBJECTIVE: To explore the safety, feasibility, and clinical curative effect of endoscopy-assisted laparoscopic resections for gastric gastrointestinal stromal tumors (GISTs). MATERIALS AND METHODS: We retrospectively compared the general condition of 41 GIST patients undergoing endoscopy-assisted laparoscopic resections (n = 41, combined group) with those undergoing traditional open gastrectomy (n = 43, open surgery group). RESULTS: All patients survived during the surgery. The average operation time of the combined group and the open surgery group was 90 ± 40 minutes and 120 ± 60 minutes, respectively, and no significant difference (P = .088) was observed. Bleeding volume during operation was significantly lower [(50 ± 20 versus 150 ± 40) mL, P < .001] and recovery time of the gastrointestinal function was significantly shorter in the combined group [(2.02 ± 0.99) days versus (3.02 ± 1) days, P < .001]. No statistical difference was found in the postoperative complications (5% versus 12%, P = .442) or GIST recurrence (2.44% versus 2.33%, P = 1.000) between the two groups. Follow-up visit showed no death. CONCLUSION: For GIST patients who attempted to receive gastrectomy, endoscopy-assisted laparoscopic resections showed advantages on the operation time, bleeding volume, and recovery time and are suggested as a better alternative for GISTs.

Effect of preservation of Denonvilliers' fascia during laparoscopic resection for mid-low rectal cancer on protection of male urinary and sexual functions.

The aim of this study was to investigate the effect of preservation of Denonvilliers' fascia (DF) during laparoscopic resection for mid-low rectal cancer on protection of male urogenital function. Whether preservation of DF during TME is effective for protection of urogenital function is largely elusive.Seventy-four cases of male mid-low rectal cancer were included. Radical laparoscopic proctectomy was performed, containing 38 cases of preservation of DF (P-group) and 36 cases of resection of DF (R-group) intraoperatively. Intraoperative electrical nerve stimulation (INS) on pelvic autonomic nerve was performed and intravesical pressure was measured manometrically. Urinary function was evaluated by residual urine volume (RUV), International Prostatic Symptom Score (IPSS), and quality of life (QoL). Sexual function was evaluated using the International Index of Erectile Function (IIEF) scale and ejaculation function classification.Compared with performing INS on the surfaces of prostate and seminal vesicles in the R-group, INS on DF in the P-group exhibited higher increasing intravesical pressure (7.3 ±â€Š1.5 vs 5.9 ±â€Š2.4 cmH2O, P = 0.008). In addtion, the P-group exhibited lower RUV (34.3 ±â€Š27.2 vs 57.1 ±â€Š50.7 mL, P = 0.020), lower IPSS and QoL scores (7 days: 6.1 ±â€Š2.4 vs 9.5 ±â€Š5.9, P = 0.002 and 2.2 ±â€Š1.1 vs 2.9 ±â€Š1.1, P = 0.005; 1 month: 5.1 ±â€Š2.4 vs 6.6 ±â€Š2.2, P = 0.006 and 1.6 ±â€Š0.7 vs 2.1 ±â€Š0.6, P = 0.003, respectively), higher IIEF score (3 months: 10.7 ±â€Š2.1 vs 8.9 ±â€Š2.0, P = 0.000; 6 months: 14.8 ±â€Š2.2 vs 12.9 ±â€Š2.2, P = 0.001) and lower incidence of ejaculation dysfunction (3 months: 28.9% vs 52.8%, P = 0.037; 6 months: 18.4% vs 44.4%, P = 0.016) postoperatively.Preservation of DF during laparoscopic resection for selective male mid-low rectal cancer is effective for protection of urogenital function.

Comparison of laparoscopic versus open complete mesocolic excision for right colon cancer.

AIM: To explore the feasibility, safety, efficacy, and short-term oncologic outcomes of laparoscopic-assisted complete mesocolic excision (CME) for right colon cancer. METHODS: The clinical data from 102 patients with right colon cancer who underwent laparoscopic CME (n = 53; LS group) and open CME (n = 49; OS group) from June 2012 to December 2013 were retrospectively reviewed. Outcomes of the two groups were compared. RESULTS: There were no conversions to open surgery in the LS group. The operative time in the LS group was similar to that in the OS group (194 ± 57 vs. 177 ± 51 min, respectively, p = 0.118). Intraoperative blood loss was significantly less in the LS group compared with the OS group (94 ± 56 vs. 118 ± 60 ml, respectively, p = 0.039). There was no difference in the total number of harvested lymph nodes (14 ± 6 vs. 13 ± 5, respectively, p = 0.313). The time to resume liquid diet (3 ± 2 vs. 5 ± 2 d, p < 0.001) and length of hospital stay (11 ± 4 vs. 14 ± 6 d, p = 0.002) were significantly shorter in the LS group. The rate of complications was similar between the groups (4% vs. 12%, respectively, p = 0.222). No recurrences were noted in either group during follow-up (range, 6-24 months). CONCLUSION: Laparoscopic CME is a safe, feasible, and effective minimally invasive procedure for right colon cancer.

Laparoscopic total colectomy and proctocolectomy for the treatment of familial adenomatous polyposis.

OBJECTIVE: To evaluate the safety, feasibility and efficacy of Laparoscopic prophylactic treatment of familial adenomatous polyposis (FAP). METHODS: Perioperative data and surgical outcomes of 11 FAP patients who underwent laparoscopic surgery between January 2012 and June 2014 in our hospital were analyzed retrospectively. Results 2: Patients had laparoscopic total proctocolectomy with ileostomy, and 9 patients had laparoscopic total colectomy with ileorectal anastomosis. The median number of harvested lymph nodes was 36 (range, 21~46). The mean operating time was 330 minutes with a range of 240 to 380 minutes. Blood loss ranged from 90 to 200 ml with a median being 150 ml. The median incision length was 4 (3-5) cm. The bowel function recovered by the third (range from 2~4 day) postoperatively. The follow-up time of these patients were 3~32 months (median 20 months) respectively and no local recurrence or distant metastases were found. CONCLUSION: Laparoscopic prophylactic treatment for FAP can be performed safely and effectively with the advantage of minimal invasion by experienced surgeons.

Laparoscopic resection for rectal cancer and cholecystectomy for patient with situs inversus totalis.

Situs inversus totalis (SIT) is a rare congenital anomaly presenting with complete transposition of thoracic and abdominal viscera. Laparoscopic surgery for either rectal cancer or gallbladder diseases with SIT is rarely reported in the literature. A 39-year-old woman was admitted to hospital owing to rectal cancer. She was diagnosed with SIT by performing radiography and abdominal computed tomography scan as a routine preoperative investigation. We performed laparoscopic resection for rectal cancer successfully in spite of technical difficulties caused by abnormal anatomy. One year later, she was diagnosed with cholecysticpolyp, and we performed laparoscopic cholecystectomy for her uneventfully. With this case, we believe that performance by an experienced laparoscopic surgeon, either laparoscopic resection for rectal cancer or cholecystectomy with SIT is safe and feasible.

Laparoscopic lysis of the ligament of treitz for superior mesenteric artery syndrome.

BACKGROUND: Superior mesenteric artery (SMA) syndrome (SMAS) is a rare condition caused by compression of the third portion of the duodenum by the SMA. The effect of the laparoscopic management of SMAS remains poorly understood. This study aimed to investigate the feasibility and effect of the laparoscopic management for SMAS. METHODS: We retrospectively reviewed 19 cases of SMAS who underwent surgical interventions in The Third Affiliated Hospital of Sun Yat-sen University between June 2006 and October 2013, consisting of 8 cases of duodenojejunostomy (DJ) and 11 cases of laparoscopic lysis of the ligament of Treitz (LL-LOT). A telephone survey was conducted to collect the follow-up status. RESULTS: Either DJ or LL-LOT was performed smoothly. The median operative time of the laparoscopic procedure and DJ was 56 and 95 min, respectively. Median blood loss was 10 versus 35 ml. Median postoperative hospital stays in both were 8 days. Ten cases of the laparoscopic group recovered uneventfully, while 1 case still presented symptoms of abdominal distention. Upper gastrointestinal fluoroscopy showed marked 'to-and-fro' peristalsis. An additional DJ was performed 35 days later to resolve her symptoms. CONCLUSIONS: LL-LOT is simple, feasible, minimally invasive and effective for SMAS with no severe duodenum 'to-and-fro' peristalsis.

A new BODIPY-based long-wavelength fluorescent probe for chromatographic analysis of low-molecular-weight thiols.

A new long-wavelength fluorescent probe, 1,7-dimethyl-3,5-distyryl-8-phenyl-(4'-iodoacetamido)difluoroboradiaza-s-indacene (DMDSPAB-I), was designed and synthesized for thiol labeling in high-performance liquid chromatography (HPLC). The excitation and emission wavelengths of DMDSPAB-I are 620 and 630 nm, respectively, with a high fluorescence quantum yield of 0.557, which is advantageous in preventing interference of intrinsic fluorescence from complex biological matrices and enabling high sensitivity HPLC. Based on DMDSPAB-I, a reversed-phase HPLC method was developed for measuring low-molecular-weight thiols including glutathione, cysteine, homocysteine, N-acetylcysteine, cysteinylglycine, and penicillamine. After the specific reaction of DMDSPAB-I with thiols, baseline separation of all six stable derivatives was achieved through isocratic elution on a C18 column within 25 min, with the limits of detection (signal-to-noise ratio = 3) from 0.24 nmol L(-1) for glutathione to 0.72 nmol L(-1) for penicillamine. The proposed method was validated in part by measuring thiols in blood samples from mice, with recoveries of 95.3-104.3%.

E-cadherin-transfected neural stem cells transplantation for spinal cord injury in rats.

The effects of E-cadherin-transfected neural stem cells (NSCs) transplantation for spinal cord injury (SCI) in rats were investigated. Sixty SD rats were randomly divided into model control group, NSCs group, empty plasmid group and E-cadherin overexpression group (n=15 each). The animal SCI model was established by using the modified Allen's method. NSCs were cultured. Rats in NSCs group were subjected to NSCs transplantation. E-cadherin gene eucaryotic expression vector and pcDNA3.1-E-cadherin were respectively transfected into cultured NSCs, serving as empty plasmid group and E-cadherin overexpression group respectively. At 7th day after transplantation, neurological function of all rats was assessed by Tarlov score. After rats were sacrificed in each group, the number of BrdU and Nestin positive cells was counted by immunohistochemistry. Immumofluorescence method was used to detect the expression of neurofilament protein (NF) and glial fibrillary acidic protein (GFAP). As compared with model control group, the Tarlov score and the number of of BrdU and Nestin positive cells, and the expression of NF and GFAP in NSCs group, empty plasmid group, and E-cadherin overexpression group were increased significantly (P<0.05), and those in the E-cadherin overexpression group were increased more significantly than the other transplantation groups (P<0.05). It was suggested that E-cadherin could be conductive to nerve regeneration and repair probably by promoting the proliferation and differentiation of NSCs.

Dual labeling for simultaneous determination of nitric oxide, glutathione and cysteine in macrophage RAW264.7 cells by microchip electrophoresis with fluorescence detection.

A simple, rapid and efficient method based on microchip electrophoresis coupled with fluorescence detection (MCE-FLD) was developed for simultaneous determination of nitric oxide (NO), glutathione (GSH) and cysteine (Cys) using dual labeling strategy. Two highly reactive fluorogenic probes, 1,3,5,7-tetramethyl-8-(3',4'-diaminophenyl)-difluoroboradiaza-s-indacene (DAMBO) and 1,3,5,7-tetramethyl-8-phenyl-(2-maleimide)-difluoroboradiaza-s-indacene (TMPAB-o-M), were used for labeling NO and thiols, respectively, under physiological conditions. The rapid separation and sensitive detection of the derivatives were achieved on a glass microchip within 70s in a running buffer of 20mM H3Cit-Na2HPO4 solution (pH 7.4) containing 15% (v/v) acetonitrile at a separation voltage of 2400V. The limits of detection (S/N=3) for NO, GSH and Cys were 7.0, 3.0 and 2.0nM, respectively. The proposed method was validated by measuring intracellular levels of NO and biothiols in macrophage RAW264.7 cells.

Rapid and sensitive determination of free thiols by capillary zone electrophoresis with near-infrared laser-induced fluorescence detection using a new BODIPY-based probe as labeling reagent.

A CZE with near-infrared (NIR) LIF detection method has been developed for the analysis of six low molecular weight thiols including glutathione, homocysteine, cysteine, γ-glutamylcysteine, cysteinylglycine, and N-acetylcysteine. For this purpose, a new NIR fluorescent probe, 1,7-dimethyl-3,5-distyryl-8-phenyl-(4'-iodoacetamido)difluoroboradiaza-s-indacene was utilized as the labeling reagent, whose excitation wavelength matches the commercially available NIR laser line of 635 nm. The optimum procedure included a derivatization step of the free thiols at 45°C for 25 min and CZE analysis conducted within 14 min in the running buffer containing 16 mmol/L pH 7.0 sodium citrate and 60% v/v ACN. The LODs (S/N = 3) ranged from 0.11 nmol/L for N-acetylcysteine to 0.31 nmol/L for γ-glutamylcysteine, which are better than or comparable to those reported with other derivatization-based CE-LIF methods. As the first trial of NIR CE-LIF method for thiol determination, the practical application of the proposed method has been validated by detecting thiols in cucumber and tomato samples with recoveries of 96.5-104.3%.

Development of a potential method based on microchip electrophoresis with fluorescence detection for the sensitive determination of intracellular thiols in RAW264.7 cells.

This paper, for the first time, reported the development of a simple, rapid, and reliable method for the separation and sensitive determination of four thiol compounds including homocysteine, cysteine, glutathione, and N-acetylcysteine based on glass MCE with fluorescence detection using a highly reactive fluorogenic probe, 1,3,5,7-tetramethyl-8-phenyl-(2-maleimide)-difluoroboradiaza-s-indacene (TMPAB-o-M), as the labeling reagent. TMPAB-o-M reacted selectively with thiols to produce highly fluorescent derivatives and the highest derivatization efficiency was achieved within 6 min in physiological conditions. After the optimization of separation conditions, a baseline separation of the four thiol compounds was achieved with the detection limits ranging from 2 nM for glutathione to 4 nM for cysteine (S/N = 3) and RSDs (n = 5) in the range of 3.2-3.8%. The proposed method was significantly sensitive compared to those using electrochemical or even LIF detection in MCE-based setup reported previously, and applied to the determination of intracellular thiols in macrophage RAW264.7 cells.

[Surgical treatment for endoscopically unresectable polyps of colon and rectum].

OBJECTIVE: To explore the characteristics and risks of cancer in endoscopically unresectable polyps and compare the surgical outcomes of different operations. METHODS: A retrospective review of 40 patients undergoing surgical operations for polyps unresectable at colonoscopy between August 2006 and July 2012 from Department of Gastrointestinal Surgery was performed. The follow-up period was 3 to 72 months (median: 24.5 months). RESULTS: The rate of endoscopically unresectable polyps with invasive cancer was 67.5% (27/40). And it was significantly influenced by patient age and number of polyps (both P < 0.01). Perioperative volume of blood loss ((86 ± 58) ml vs (44 ± 32) ml, P = 0.0066), time to first flatus ((2.7 ± 1.3) d vs (1.7 ± 0.6) d, P = 0.0018), incidence of complication (2 cases vs 0, P = 0.0365) and hospital stay ((11.2 ± 1.0) d vs (15.0 ± 5.0) d, P = 0.0164) were significantly different between open colectomy and laparoscopic group. And the long-term survival outcomes were similar in both groups (90.9% (10/11) vs 100.0% (27/27), 90.9% (10/11) vs 96.3% (26/27), both P > 0.05). CONCLUSIONS: Endoscopically unresectable polyps of colon and rectum have high malignancy rate. Polyps in elderly patients and multiple polyps are more likely to develop invasive cancer. Long-term outcomes are similar between open colectomy and laparoscopic colectomy groups, but laparoscopic group has better short-term outcomes. For endoscopically unresectable polyps, laparoscopic colectomy may be the first choice.

[Comparison of laparoscopy-assisted distal gastrectomy with open gastrectomy for advanced gastric cancer].

OBJECTIVE: To evaluate the feasibility, safety and short-term outcomes of laparoscopy-assisted distal gastrectomy for advanced gastric cancer. METHODS: From January 2007 to June 2008, 135 patients with advanced gastric cancer in the lower or middle stomach were operated, of whom 66 underwent laparoscopy-assisted distal gastrectomy(LADG) with D2 dissection of lymph nodes and 69 received conventional open D2 distal gastrectomy(ODG). Clinical data were recorded and compared between the two groups. RESULTS: There were no significant differences in age, gender, and TNM staging between LADG and ODG(all P>0.05). All the patients in the LADG group underwent gastrectomy and lymph nodes dissection successfully without conversion to open surgery and no operative deaths occurred. The operative time was significantly longer for the LADG group than for the ODG group[(266.1±55.1) min vs. (223.8±26.8) min)]. The patients in the laparoscopic surgery group had less blood loss[(131.9±88.7) ml vs.(342.3±178.7) ml], earlier recovery of bowel activity[(3.18±1.22) d vs.(4.50±1.59) d], and shorter hospitalization time[(9.20±3.39) d vs. (11.35±4.61) d]. No significant differences were found in the total number of retrieved lymph nodes(25.81±12.53 vs. 27.47±10.28). The morbidity of complications was comparable between two groups(6.1% vs. 15.94%). No mortality and recurrence were observed during a follow-up period of 1-19 months. CONCLUSIONS: LADG with D2 lymph node dissection is a safe and feasible procedure with adequate lymphadenectomy for advanced gastric cancer.

Coaction of spheroid-derived stem-like cells and endothelial progenitor cells promotes development of colon cancer.

Although some studies described the characteristics of colon cancer stem cells (CSCs) and the role of endothelial progenitor cells (EPCs) in neovascularization, it is still controversial whether an interaction exists or not between CSCs and EPCs. In the present study, HCT116 and HT29 sphere models, which are known to be the cells enriching CSCs, were established to investigate the roles of this interaction in development and metastasis of colon cancer. Compared with their parental counterparts, spheroid cells demonstrated higher capacity of invasion, higher tumorigenic and metastatic potential. Then the in vitro and in vivo relationship between CSCs and EPCs were studied by using capillary tube formation assay and xenograft models. Our results showed that spheroid cells could promote the proliferation, migration and tube formation of EPCs through secretion of vascular endothelial growth factor (VEGF). Meanwhile, the EPCs could increase tumorigenic capacity of spheroid cells through angiogenesis. Furthermore, higher microvessel density was detected in the area enriching cancer stem cells in human colon cancer tissue. Our findings indicate that spheroid cells possess the characteristics of cancer stem cells, and the coaction of CSCs and EPCs may play an important role in the development of colon cancer.