Single-nucleus genomics in outbred rats with divergent cocaine addiction-like behaviors reveals changes in amygdala GABAergic inhibition

The amygdala processes positive and negative valence and contributes to addiction, but the cell-type-specific gene regulatory programs involved are unknown. We generated an atlas of single-nucleus gene expression and chromatin accessibility in the amygdala of outbred rats with high and low cocaine addiction-like behaviors following prolonged abstinence. Differentially expressed genes between the high and low groups were enriched for energy metabolism across cell types. Rats with high addiction index (AI) showed increased relapse-like behaviors and GABAergic transmission in the amygdala. Both phenotypes were reversed by pharmacological inhibition of the glyoxalase 1 enzyme, which metabolizes methylglyoxal-a GABAA receptor agonist produced by glycolysis. Differences in chromatin accessibility between high and low AI rats implicated pioneer transcription factors in the basic helix-loop-helix, FOX, SOX and activator protein 1 families. We observed opposite regulation of chromatin accessibility across many cell types. Most notably, excitatory neurons had greater accessibility in high AI rats and inhibitory neurons had greater accessibility in low AI rats.

[Advances in three-dimensional tumor models for colorectal cancer]

Conventional tumor culture models include two-dimensional tumor cell cultures and xenograft models. The former has disadvantages including lack of tumor heterogeneity and poor clinical relevance, while the latter are limited by the slow growth, low engraftment successful rate, and high cost. In recent years, in vitro three-dimensional (3D) tumor models have emerged as the tool to better recapitulate the spatial structure and the in vivo environment of tumors. In addition, they preserve the pathological and genetic features of tumor cells and reflect the complex intracellular and extracellular interactions of tumors, which have become a powerful tool for investigating the tumor mechanism, drug screening, and personalized cancer treatment. 3D tumor model technologies such as spheroids, organoids, and microfluidic devices are maturing. Application of new technologies such as co-culture, 3D bioprinting, and air-liquid interface has further improved the clinical relevance of the models. Some models recapitulate the tumor microenvironment, and some can even reconstitute endogenous immune components and microvasculature. In recent years, some scholars have combined xenograft models with organoid technology to develop matched in vivo/in vitro model biobanks, giving full play to the advantages of the two technologies, and providing an ideal research platform for individualized precision therapy for specific molecular targets in certain subtypes of tumors. So far, the above technologies have been widely applied in the field of colorectal cancer research. Our research team is currently studying upon the application of patient-derived tumor cell-like clusters, a self-assembly 3D tumor model, in guiding the selection of postoperative chemotherapy regimens for colorectal cancer. A high modeling success rate and satisfactory results in the drug screening experiments have been achieved. There is no doubt that with the advancement of related technologies, 3D tumor models will play an increasingly important role in the research and clinical practice of colorectal cancer.

[Meta-analysis of the effects of xenogeneic acellular dermal matrix dressings in the treatment of wounds in burn patients]

Objective: To evaluate the efficacy and safety of xenogeneic acellular dermal matrix (ADM) dressings for the treatment of wounds in burn patients. Methods: The meta-analysis method was adopted. Databases including Chinese Journal Full-text Database, Wanfang Database, VIP Database, and Chinese Biomedical Database were retrieved with the search terms in Chinese version of ", , , " and PubMed, Embase, Web of Science, and Cochrane Library were retrieved with the search terms in English version of "xenogeneic acellular dermal matrix, dressing, burn wound, burn" to obtain the publicly published randomized controlled trials on the efficacy of xenogeneic ADM dressings for the treatment of wounds in burn patients from the establishment of each database to December 2021. The outcome indexes included wound healing time, ratio of scar hyperplasia, Vancouver scar scale (VSS) score, ratio of complications, ratio of skin grafting, and ratio of bacteria detection. Rev Man 5.3 and Stata 14.0 statistical softwares were used to conduct a meta-analysis of eligible studies. Results: A total of 1 596 burn patients from 16 studies were included, including 835 patients in experimental group who received xenogeneic ADM dressings therapy and 761 patients in control group who received other methods therapy. The bias risk of all the 16 included studies was uncertain. Compared with those in control group, patients in experimental group had significantly shorter wound healing time, lower VSS scores (with standardized mean differences of -2.50 and -3.10, 95% confidence intervals of -3.02--1.98 and -4.87--1.34, respectively, P values both <0.05), and lower ratios of scar hyperplasia, complications, skin grafting, and bacteria detection (with relative risks of 0.58, 0.23, 0.32, and 0.27, 95% confidence intervals of 0.43-0.80, 0.14-0.37, 0.15-0.67, and 0.11-0.69, respectively, P<0.05). Subgroup analysis showed that the difference of intervention measures in control group might be the source of heterogeneity in wound healing time. There was no publication bias in ratio of scar hyperplasia (P≥0.05), while there was publication bias in wound healing time, VSS score, and ratio of complications (P<0.05). Conclusions: Xenogeneic ADM dressings can shorten the wound healing time of burn patients, reduce the VSS score and the ratios of scar hyperplasia, complications, skin grafting, and bacteria detection.

[Effect of deep dermal tissue dislocation injury on skin fibrosis in pig]

Objective: To explore the effect of deep dermal tissue dislocation injury on skin fibrosis in pig, in order to provide some theoretical basis for burn scar treatment. Methods: The experimental research method was applied. Six 2-month-old female Duroc pigs were taken. Fifteen operative areas on the right dorsum of pigs on which medium-thick skin grafts and deep dermal tissue slices were cut and re-implanted were included into dermal in situ reimplantation group, and fifteen operative areas on the left dorsum of pigs on which medium-thick skin grafts and deep dermal tissue slices were cut and the deep dermal tissue slice was placed under the fat layer were included into the dermal dislocation group. The hair growth in the operative areas on post-injury day (PID) 7, 14, and 21 and the cross-sectional structure on PID 14 were observed in the two groups. On PID 7, 14, and 21, the skin thickness (the distance from the epidermis to the upper edge of the fat), the dermal thickness (the distance from the lower edge of the epidermis to the upper edge of the fat, excluding the fibrotic tissue thickness between the dermis and the fat), and the fibrosis tissue thickness of the dermis-fat interface (from the lower edge of the deep dermis to the upper edge of the fat in dermal in situ reimplantation group and from the lower edge of the superficial dermis to the upper edge of the fat in dermal dislocation group) in the operative areas were measured and compared between the two groups; the fibrotic tissue thickness at the dermal cutting interface (from the lower edge of the superficial dermis to the upper edge of the deep dermis) in the operative areas in dermal in situ reimplantation group was measured and compared with the fibrotic tissue thickness at the dermal-fat interface. Sirius red staining was performed to observe and compare the type Ⅰ and Ⅲ collagen content in the dermal-fat interface in the operative areas between the 2 groups and between the dermal cutting interface and dermal-fat interface in the operative areas in dermal in situ reimplantation group. Immunohistochemical staining was performed to observe the positive expressions of proliferating cell nuclear antigen (PCNA), transforming growth factor β1 (TGF-β1), fibroblast growth factor 2 (FGF-2), and hepatocyte growth factor (HGF) in the operative areas in the two groups. The sample number was 6. Data were statistically analyzed with independent sample t test. Results: On PID 7, 14, and 21, the hairs in the operative areas in dermal in situ reimplantation group were denser than those in dermal dislocation group. On PID 14, the skin cross section in the operative areas in dermal dislocation group showed a "sandwich"-like structure, while the skin cross section in the operative areas in dermal in situ reimplantation group had normal structure. On PID 7, 14, and 21, the skin thickness in the operative areas in dermal dislocation group was (4 234±186), (4 688±360), and (4 548±360) μm, respectively, which was close to (4 425±156), (4 714±141), and (4 310±473) μm in dermal in situ reimplantation group (P>0.05); the dermal thickness in the operative areas in dermal dislocation group was significantly thinner than that in dermal in situ reimplantation group (with t values of -9.73, -15.85, and -15.41, respectively, P<0.01); the fibrotic tissue thickness at the dermal-fat interface in the operative areas in dermal dislocation group was significantly thicker than that in dermal in situ reimplantation group (with t values of 14.48, 20.58, and 15.67, respectively, P<0.01); there was no statistically significant difference between the fibrotic tissue thickness at the dermal-fat interface and the dermal cutting interface in the operative areas in dermal in situ reimplantation group (P>0.05). On PID 7, 14, 21, the type Ⅲ collagen content in the dermal-fat interface in the operative areas in dermal dislocation group was increased significantly compared with that in dermal in situ replantation group (with t values of 2.65, 0.61, and 7.39, respectively, P<0.05 or P<0.01), whereas there were no statistically significant differences in the type Ⅰ collagen content at the dermal-fat interface in the operative areas between the 2 groups (P>0.05) and the type Ⅰ and Ⅲ collagen content between the dermal-fat interface and the dermal cutting interface in the operative areas in dermal in situ reimplantation group (P>0.05). On PID 7, 14, and 21, PCNA, TGF-β1, FGF-2, and HGF were positively expressed in the superficial dermis and adipose tissue in the operative areas in dermal dislocation group, while PCNA, TGF-β1, FGF-2, and HGF were positively expressed in the superficial dermis, deep dermis, and adipose tissue in the operative areas in dermal in situ reimplantation group. Conclusions: Inadequate intrinsic thickness of dermal tissue is the key factor causing fibrosis, and the biological purpose of fibrosis is to "compensate" the intrinsic thickness of the skin. Besides, adipose tissue may also be an important component of fibrotic skin repair.

[Survival and prognosis analysis of patients with Hodgkin lymphoma treated with standard treatment paradigm]

Objective: To analyze the survival and prognosis of Hodgkin lymphoma (HL) patients receiving standard first-line therapy. Methods: Data of clinical characteristics and treatment outcomes of patients with HL diagnosed in Cancer Hospital Chinese Academy of Medical Sciences (CHCAMS) from January 1st, 2000 to December 31st, 2018 who received standard first-line treatment were retrospectively analyzed and compared with that of HL patients who received treatment in the Surveillance, Epidemiology and End Results (SEER) database in the United States during the same period. Factors associated with freedom from progression (FFP) of patients in CHCAMS were analyzed. Treatment and survival data of patients with relapsed/refractory HL (r/rHL) who had failed the standard first-line treatment during the corresponding period in CHCAMS were collected to analyze the outcomes of salvage therapy. Results: A total of 764 HL patients in CHCAMS were included in this study. The median age was 30 years (range, 14-83 years), with 424 males and 340 females. By February 26th, 2022, the patients were followed-up for a median time of 111 months(range, 0.3-262.0 months). Lymphoma-specific survival (LSS) rate and overall survival (OS) rate at 10 years for HL patients in CHCAMS was 91.7% (95%CI: 89.5%-93.9%) and 87.1% (95%CI: 84.5%-89.8%), respectively. LSS and OS rate at 10 years for HL patients from SEER database was 86.8% (95%CI: 86.3%-87.2%) and 79.0% (95%CI: 78.5%-79.5%), respectively. The unadjusted LSS and OS rate for patients in CHCAMS were higher than those for patients from SEER database (both P<0.001). No significant difference was observed in LSS and OS rate (both P>0.05) between the two groups after adjustment. European Organization for Research and Treatment of Cancer staging system (early-stage unfavorable: HR=2.35, 95%CI: 1.13-4.89, P=0.023; advanced stage: HR=5.44, 95%CI: 2.62-11.30, P<0.001) and serum β2 microglobulin (HR=1.67, 95%CI: 1.08-2.58, P=0.021) were influencing factors of FFP for patients in CHCAMS. The complete remission rate, median progression-free survival (PFS), 5-year PFS rate and 5-year OS rate for the 116 patients with r/rHL was 37.9% (95%CI: 29.6%-47.0%), 15.0 months (95%CI: 9.9-20.1 months), 29.9% (95%CI: 20.9%-38.9%) and 62.9% (95%CI: 54.1%-71.7%), respectively. Conclusions: The outcomes of HL patients receiving standard first-line treatment are excellent. However, the therapeutic effect of HL patients who incurrs disease progression or relapse after standard first-line treatment is not satisfying.

[Analysis of prognosis factors of postoperative cardiac complications in colorectal cancer patients with comorbid coronary artery disease]

Objective: To examine the prognosis factors of postoperative cardiac complications in colorectal cancer patients co-morbidated with coronary artery disease. Methods: Clinical data of 449 patients colorectal cancer patients co-morbidated with coronary artery disease accepted redical surgery from April 2013 to April 2020 at Department of General Surgery, Peking Union Medical College Hospital were analyzed retrospectively. There were 306 males and 143 females, aging (68.7±8.9) years (range: 44 to 89 years). Postoperative acute coronary syndrome, new-onset arrhythmia and heart failure that causes clinical symptoms were recorded as cardiac complications. t test, χ2 test and Fisher exact test were used for univariate analysis of prognosis factors of postoperative cardiac events. The variables with P<0.05 were included in the multivariate Logistic regression was used to determine the independent prognosis factors. Results: After surgery, 44 patients (9.8%) suffered from at least one cardiac event, including 30 patients with acute coronary syndrome, 19 patients with new-onset arrhythmia and 9 patients with heart failure. There were 3 deaths in the cohort within 30 days after surgery. Two patients died from cardiac-related complications, and one from septic shock due to postoperative anastomotic leaks. On Univariate analysis showed that cardiac complications were associated with age ≥80 years, co-morbidated diabetes, emergency surgery, re-operation, anastomotic leakage, intestinal flora disorder and elevation of preoperative neutrophil-lymphocyte ratio (χ2: 4.308 to 12.219, all P<0.05). Multivariate Logistic regression analysis identified age ≥80 years(OR=3.195, 95%CI: 1.379 to 7.407, P=0.007), co-morbidated diabetes (OR=2.551, 95%CI: 1.294 to 5.025, P=0.007), emergency surgery (OR=4.717, 95%CI: 1.052 to 20.833, P=0.043), and elevated preoperative neutrophil-lymphocyte ratio (OR=1.114, 95%CI: 1.018 to 1.218, P=0.018) as independent prognosis factors for cardiac complications. Conclusions: Emergency surgery, advanced age, co-morbidated type 2 diabetes and elevated preoperative neutrophil-lymphocyte ratio may increase the risk of postoperative cardiac complications in colorectal cancer patients with coronary artery disease. Surgeons should strictly master surgical indications, pay attention to preoperative assessment, perioperative monitoring, and diagnosis and treatment of postoperative complications in order to reduce the risk of complications.

[Safety and prognosis analysis of transanal total mesorectal excision versus laparoscopic mesorectal excision for mid-low rectal cancer]

Objective: To compare the short-term and long-term outcomes between transanal total mesorectal excision (taTME) and laparoscopic total mesorectal excision (laTME) for mid-to-low rectal cancer and to evaluate the learning curve of taTME. Methods: This study was a retrospective cohort study. Firstly, consecutive patients undergoing total mesorectal excision who were registered in the prospective established database of Division of Colorectal Diseases, Department of General Surgery, Peking Union Medical College Hospital during July 2014 to June 2020 were recruited. The enrolled patients were divided into taTME and laTME group. The demographic data, clinical characteristics, neoadjuvant treatment, intraoperative and postoperative complications, pathological results and follow-up data were extracted from the database. The primary endpoint was the incidence of anastomotic leakage and the secondary endpoints included the 3-year disease-free survival (DFS) and the 3-year local recurrence rate. Independent t-test for comparison between groups of normally distributed measures; skewed measures were expressed as M (range). Categorical variables were expressed as examples (%) and the χ(2) or Fisher exact probability was used for comparison between groups. When comparing the incidence of anastomotic leakage, 5 variables including sex, BMI, clinical stage evaluated by MRI, distance from tumor to anal margin evaluated by MRI, and whether receiving neoadjuvant treatment were balanced by propensity score matching (PSM) to adjust confounders. Kaplan-Meier curve and Log-rank test were used to compare the DFS of two groups. Cox proportional hazard model was used to analyze and determine the independent risk factors affecting the DFS of patients with mid-low rectal cancer. Secondly, the data of consecutive patients undergoing taTME performed by the same surgical team (the trananal procedures were performed by the same main surgeon) from February 2017 to March 2021 were separately extracted and analyzed. The multidimensional cumulative sum (CUSUM) control chart was used to draw the learning curve of taTME. The outcomes of 'mature' taTME cases through learning curve were compared with laTME cases and the independent risk factors of DFS of 'mature' cases were also analyzed. Results: Two hundred and forty-three patients were eventually enrolled, including 182 undergoing laTME and 61 undergoing taTME. After PSM, both fifty-two patients were in laTME group and taTME group respectively, and patients of these two groups had comparable characteristics in sex, age, BMI, clinical tumor stage, distance from tumor to anal margin by MRI, mesorectal fasciae (MRF) and extramural vascular invasion (EMVI) by MRI and proportion of receiving neoadjuvant treatment. After PSM, as compared to laTME group, taTME group showed significantly longer operation time [(198.4±58.3) min vs. (147.9±47.3) min, t=-4.321, P<0.001], higher ratio of blood loss >100 ml during surgery [17.3% (9/52) vs. 0, P=0.003], higher incidence of anastomotic leakage [26.9% (14/52) vs. 3.8% (2/52), χ(2)=10.636, P=0.001] and higher morbidity of overall postoperative complications [55.8%(29/52) vs. 19.2% (10/52), χ(2)=14.810, P<0.001]. Total harvested lymph nodes and circumferential resection margin involvement were comparable between two groups (both P>0.05). The median follow-up for the whole group was 24 (1 to 72) months, with 4 cases lost, giving a follow-up rate of 98.4% (239/243). The laTME group had significantly better 3-year DFS than taTME group (83.9% vs. 73.0%, P=0.019), while the 3-year local recurrence rate was similar in two groups (1.7% vs. 3.6%, P=0.420). Multivariate analysis showed that and taTME surgery (HR=3.202, 95%CI: 1.592-6.441, P=0.001) the postoperative pathological staging of UICC stage II (HR=13.862, 95%CI:1.810-106.150, P=0.011), stage III (HR=8.705, 95%CI: 1.104-68.670, P=0.040) were independent risk factors for 3-year DFS. Analysis of taTME learning curve revealed that surgeons would cross over the learning stage after performing 28 cases. To compare the two groups excluding the cases within the learning stage, there was no significant difference between two groups after PSM no matter in the incidence of anastomotic leakage [taTME: 6.7%(1/15); laTME: 5.3% (2/38), P=1.000] or overall complications [taTME: 33.3%(5/15), laTME: 26.3%(10/38), P=0.737]. The taTME was still an independent risk factor of 3-year DFS only analyzing patients crossing over the learning stage (HR=5.351, 95%CI:1.666-17.192, P=0.005), and whether crossing over the learning stage was not the independent risk factor of 3-year DFS for mid-low rectal cancer patients undergoing taTME (HR=0.954, 95%CI:0.227-4.017, P=0.949). Conclusions: Compared with conventional laTME, taTME may increase the risk of anastomotic leakage and compromise the oncological outcomes. Performing taTME within the learning stage may significantly increase the risk of postoperative anastomotic leakage.

[Spectral CT multi-parameter imaging in preoperatively evaluation the status of lymphovascular and perineural invasion of gastric cancer]

Objective: To explore the application value of spectral CT multi-parameter imaging in preoperative assessment the status of lymphovascular invasion (LVI) and perineural invasion (PNI) in patients with gastric cancer. Methods: A total of 62 patients who underwent energy spectral CT and with pathology confirmed gastric cancer in Lanzhou Uiversity Second Hospital from September 2020 to September 2021 were retrospectively collected, which including 46 males and 16 females, aged from 36 to 71 (57.5±9.1) years. According to the presence or absence of LVI/PNI in postoperative pathological results, they were divided into the positive group (42 cases) and the negative group (20 cases). The CT values of 40 keV and 70 keV (CT_{40 keV}, CT_{70 keV}), iodine concentration (IC), normalized iodine concentration (NIC) were measured in the arterial phase, the venous phase, and the delay phase, and the spectral curve slope of 40 keV to 70 keV (K_(40-70)) and the combined parameters (the arterial phase: AP~all, the venous phase: VP~all, the delay phase: DP~all) were calculated. Spectral parameters between the positive and negative groups were compared, and the receiver operating characteristic curve (ROC) with the area under the curve (AUC), sensitivity, specificity, and optimal threshold were calculated for evaluating the diagnostic performance of each parameter. Results: The CT_{40 keV}, CT_{70 keV}, K_(40-70), IC, and NIC in the arterial phase and the venous phase and the CT_{70 keV} and NIC in the delay phase of the LVI/PNI-positive group were all higher than those of the negative group [the representative parameters: the arterial phase NIC 0.14±0.04 vs 0.12±0.04, the venous phase NIC 0.5(0.5, 0.6) vs 0.4(0.4, 0.5), the delay phase NIC 0.6±0.1 vs 0.5±0.1, all P<0.05]. ROC curve analysis showed that the diagnostic efficacy of the parameters of the venous phase is better than that of the arterial phase and the delay phase, and the diagnostic efficiency of the combined parameters is better than that of the individual parameters. The AUC value, sensitivity, and specificity of the most optimal parameter VP~all of the venous phase were 0.931(95%CI:0.872-0.990), 80.95%, and 95.00%, respectively. Conclusions: In the preoperative evaluation the status of the LVI and PNI in gastric cancer, the diagnostic efficacy in the venous phase parameters is better than that in the arterial phase and delay phase, and the diagnostic efficacy of combined parameters is better than that of individual parameters.

[Histological regression and clinical benefits in patients with liver cirrhosis after long-term anti-HBV treatment]

Objective: Our study aims to determine histological regression and clinical improvement after long-term antiviral therapy in hepatitis B virus-related cirrhosis patients. Methods: Treatment-naïve chronic hepatitis B patients with histologically or clinically diagnosed liver cirrhosis were enrolled. Liver biopsies were performed after 5 years entecavir-based antiviral treatment. Patients were followed up every 6 months. Cirrhosis regression was evaluated based on Metavir system and P-I-R score. Clinical improvement was evaluated before and after the long-term treatment. Kruskal Wallis test and Wilcoxon signed-rank test were used for continuous variables, Fisher's exact test was used for categorical variables and multivariate analysis was performed using logistic regression analysis. Results: Totals of 73 patients with HBV-related liver cirrhosis were enrolled. Among them, 30 (41.1%) patients were biopsy proved liver cirrhosis and the remaining 43 (58.9%) cirrhotic patients were diagnosed by clinical features. Based on Metavir system and P-I-R score, 72.6% (53/73) patients attained histological regression. Furthermore, 30.1% (22/73) were defined as significant regression (Metavir decrease ≥2 stage), 42.5% (31/73) were mild regression (Metavir decrease 1 stage or predominantly regressive by P-I-R system if still cirrhosis after treatment) and 27.4% (20/73) were the non-regression. Compared to levels of clinical characteristics at baseline, HBV DNA, ALT, AST, liver stiffness(decreased from 12.7 to 6.4 kPa in significant regression, from 18.1 to 7.3 kPa in mild regression and from 21.4 to 11.2 kPa in non-regression)and Ishak-HAI score significantly decreased after 5 years of anti-HBV treatment, while serum levels of platelets and albumin improved remarkably (P<0.05). In multivariate analysis, only the pre-treatment liver stiffness level was associated with significant regression (OR=0.887, 95%CI: 0.802-0.981, P=0.020). Conclusions: After long-term antiviral therapy, patients with HBV-related cirrhosis are easily to attain improvements in clinical parameters, while a certain percentage of these patients still cannot achieve histological reversal.

[Analysis of change in esophageal varices and clinical characteristics in hepatitis B virus-related cirrhosis after antiviral therapy]

Objective: To clarify the effect and related factors of antiviral therapy on the change of esophageal varices in patients with hepatitis B virus-related cirrhosis. Methods: Fifty-two cases with hepatitis B virus-related cirrhosis who underwent endoscopy before and after antiviral therapy were selected from prospective cohorts. Patients were divided into three groups: no, mild, and moderate-severe based on the degree of esophageal varices. The changes in the severity of esophageal varices in each group were compared after antiviral therapy. Clinical characteristics (platelet, liver and kidney function, liver stiffness, and virological response) of patients with different regressions were analyzed. Measurement data were analyzed by independent sample t-test, one-way ANOVA, Mann-Whitney U test and Kruskal-Wallis H test, and Chi-Square test was used for count data. Results: All patients received entecavir-based antiviral therapy. The median treatment time was 3.1 (2.5-4.4) years. The proportion of patients without esophageal varices increased from 30.8% to 51.9%, the proportion of mild esophageal varices decreased from 40.4% to 30.8%, and the proportion of patients with moderate-to-severe esophageal varices decreased from 28.8% to 17.3% (χ²=14.067, P=0.001). A total of 40.4% of patients had esophageal varices regression, and 13.5% had esophageal varices progression. The progression rate was significantly higher in patients with moderate-severe esophageal varices than patients with mild and no esophageal varices (χ²=28.126, P<0.001), and 60.0% of patients with moderate-severe esophageal varices still remained in moderate-severe state after antiviral treatment. Baseline platelet count and 5-year mean change rates were significantly lower in patients with progressive moderate-to-severe esophageal varices than in those without progression (+3.3% vs. +34.1%, Z=7.00, P=0.027). Conclusion: After effective antiviral treatment, 40.4% of patients with hepatitis B virus-related cirrhosis combined with esophageal varices has obtained esophageal varices regression, but those with moderate to severe esophageal varices still have a considerable risk of progression while receiving mono antiviral treatment only. Thrombocytopenia and without significant improving are the clinical signs of progression risk after receiving antiviral treatment.

[Quality of life of patients with locally advanced rectal cancer after neoadjuvant therapy and sphincter-preserving surgery]

Objective: To investigate quality of life (QoL) of patients with locally advanced rectal cancer (LARC) who underwent low anterior resection with protective stoma under neoadjuvant therapy mode, and to explore the changes of QoL of patients from before neoadjuvant therapy to 12 months after stoma reversal. Methods: A descriptive case series study was carried out. A retrospective study was performed on patients with mid and low LARC who received complete neoadjuvant long course radiotherapy and chemotherapy, followed by radical low anterior resection (LAR) combined with protective stoma at Peking Union Medical College Hospital from December 2017 to January 2020. Inclusion criteria: (1) patients with rectal MRI assessment of mT3-4b or mN1-2 without distant metastasis (M0) before neoadjuvant therapy; (2) distance from tumor lower margin to the anal verge <12 cm; (3) rectal adenocarcinoma confirmed by biopsy before neoadjuvant therapy; (4) complete cycle of neoadjuvant therapy; (5) patients undergoing radical LAR with sphincter preservation and protective ostomy; (6) patients receiving follow-up for more than 12 months after stoma reversal. Exclusion criteria: (1) patients as grade Ⅳ to Ⅴclassified by the American Society of Anesthesiologists (ASA); (2) patients with multiple primary colorectal cancer; (3) patients with history of other malignant tumors in the past 5 years; (4) patients of emergency surgery; (5) pregnant or lactating women; (6) patients with history of severe mental illness; (7) patients with contraindication of MRI, radiotherapy, chemotherapy, or surgical treatment. A total of 83 patients were enrolled, including 51 males and 28 females with median age of 59 years and mean BMI of (24.4±3.1) kg/m(2). EORTC QLQ-CR29, international erectile function index (IIEF), Wexner constipation score and low anterior resection syndrome (LARS) score were applied to investigate the QoL of the patients before neoadjuvant therapy, 3 and 12 months after ostomy reversal, including rectal anal function and sexual function. M (P25, P75) was used for the scores of the scale. Results: (1) EORTC QLQ-CR29 score showed that before neoadjuvant therapy, before surgery, 3 months and 12 months after ostomy reversal, anxiety [64.4 (52, 0, 82.5), 75.3 (66.0, 89.5), 82.6 (78.5, 90.0), 83.6 (78.0, 91.0)] and concern about body image [76.8 (66.0, 92.0), 81.1 (76.5, 91.5), 85.5 (82.5, 94.0), 86.1 (82.0, 92.0)] were improved (all P<0.01); pelvic pain [5.4 (2.0, 8.0), 5, 0 (2.0, 7.8), 3.9 (1.0, 5.0), 3.0 (1.0, 5.0)], urinary incontinence [15.7 (7.0, 22.0), 11.1 (0, 17.5), 10.0 (0, 17.0), 9.9 (0, 16.0)], impotence [14.3 (4.2, 19.0), 12.2 (0, 16.8), 5.6 (0, 10.0), 5.2 (0.2, 8.0)], urinate [26.4 (13.0, 38.5), 13.9 (0, 20.0), 13.4 (2.5, 21.5), 13.2 (2.0, 20.0)] and mucous bloody stool [4.7 (3.0, 6.0), 2.6 (0, 5.0), 2.2 (0, 5.0), 1.9 (0, 4.0)] were improved as well (all P<0.01). The scores fluctuated in the improvement of male sexual function, abdominal pain, dry mouth, worry about body mass change, skin pain and dyspareunia, but the symptoms were significantly improved after ostomy reversal compared with before neoadjuvant therapy (all P<0.05). There were no significant changes in female sexual function, dysuria, dysgeusia and fecal incontinence after ostomy reversal compared with before neoadjuvant therapy (all P>0.05). (2) IIEF scale showed that all scores were similar before and after neoadjuvant therapy (all P>0.05). (3) Rectal and anal function scale revealed that before neoadjuvant therapy, before operation, 3 months and 12 months after stoma reversal, gas incontinence [3.1 (0, 4.0), 2.3 (0, 4.0), 1.8 (0, 4.0), 1.2 (0, 3.0)] and urgent defecation [7.2 (0, 11.0), 5.2 (0, 11.0), 2.9 (0, 9.0), 1.7 (0, 0)] were improved (all P<0.001). In terms of improving incomplete emptying sensation, the symptoms fluctuated, but the symptoms improved significantly after ostomy reversal compared with before neoadjuvant therapy (all P<0.05). While the symptoms of assistance with defecation [0 (0, 0), 0.7 (0, 1.0), 0.6 (0, 1.0), 0.7 (0, 1.0)] and defecation failure [0.2 (0, 0), 1.0 (0, 2.0), 0.8 (0, 1.5), 0.8 (0, 1.0)] showed a worsening trend (all P<0.001). Stratified analysis was performed on patients with different efficacy of neoadjuvant therapy to compare the changes in QoL before and after neoadjuvant therapy. Patients with less sensitive and more sensitive neoadjuvant therapy showed similar changes in function and symptoms. Patients with less sensitive therapy showed significant improvement in dysuria, urinary incontinence, skin pain and dyspareunia (all P<0.05), and the symptom of defecation frequency in more sensitive patients was significantly improved (P<0.05). Conclusions: For patients with LARC, neoadjuvant radiochemotherapy combined with radical LAR and protective stoma can improve QoL in many aspects. It is noted that patients show a worsening trend in the need for assistance with defecation and in defecation failure.

[Risk factors of postoperative surgical site infection in colon cancer based on a single center database]

Objective: To explore the incidence and risk factors of postoperative surgical site infection (SSI) after colon cancer surgery. Methods: A retrospective case-control study was performed. Patients diagnosed with colon cancer who underwent radical surgery between January 2016 and May 2021 were included, and demographic characteristics, comorbidities, laboratory tests, surgical data and postoperative complications were extracted from the specialized prospective database at Department of General Surgery, Peking Union Medical College Hospital. Case exclusion criteria: (1) simultaneously multiple primary colon cancer; (2) segmental resection, subtotal colectomy, or total colectomy; (3) patients undergoing colostomy/ileostomy during the operation or in the state of colostomy/ileostomy before the operation; (4) patients receiving natural orifice specimen extraction surgery or transvaginal colon surgery; (5) patients with the history of colectomy; (6) emergency operation due to intestinal obstruction, perforation and acute bleeding; (7) intestinal diversion operation; (8) benign lesions confirmed by postoperative pathology; (9) patients not following the colorectal clinical pathway of our department for intestinal preparation and antibiotic application. Univariate analysis and multivariate analysis were used to determine the risk factors of SSI after colon cancer surgery. Results: A total of 1291 patients were enrolled in the study. 94.3% (1217/1291) of cases received laparoscopic surgery. The incidence of overall SSI was 5.3% (69/1291). According to tumor location, the incidence of SSI in the right colon, transverse colon, left colon and sigmoid colon was 8.6% (40/465), 5.2% (11/213), 7.1% (7/98) and 2.1% (11/515) respectively. According to resection range, the incidence of SSI after right hemicolectomy, transverse colectomy, left hemicolectomy and sigmoid colectomy was 8.2% (48/588), 4.5% (2/44), 4.8% (8 /167) and 2.2% (11/492) respectively. Univariate analysis showed that preoperative BUN≥7.14 mmol/L, tumor site, resection range, intestinal anastomotic approach, postoperative diarrhea, anastomotic leakage, postoperative pneumonia, and anastomotic technique were related to SSI (all P<0.05). Multivariate analysis revealed that anastomotic leakage (OR=22.074, 95%CI: 6.172-78.953, P<0.001), pneumonia (OR=4.100, 95%CI: 1.546-10.869, P=0.005), intracorporeal anastomosis (OR=5.288, 95%CI: 2.919-9.577,P<0.001) were independent risk factors of SSI. Subgroup analysis showed that in right hemicolectomy, the incidence of SSI in intracorporeal anastomosis was 19.8% (32/162), which was significantly higher than that in extracorporeal anastomosis (3.8%, 16/426, χ(2)=40.064, P<0.001). In transverse colectomy [5.0% (2/40) vs. 0, χ(2)=0.210, P=1.000], left hemicolectomy [5.4% (8/148) vs. 0, χ(2)=1.079, P=0.599] and sigmoid colectomy [2.1% (10/482) vs. 10.0% (1/10), χ(2)=2.815, P=0.204], no significant differences of SSI incidence were found between intracorporeal anastomosis and extracorporeal anastomosis (all P>0.05). Conclusions: The incidence of SSI increases with the resection range from sigmoid colectomy to right hemicolectomy. Intracorporeal anastomosis and postoperative anastomotic leakage are independent risk factors of SSI. Attentions should be paid to the possibility of postoperative pneumonia and actively effective treatment measures should be carried out.

[Protective colostomy and protective ileostomy for the prevention of anastomotic leak in patients with rectal cancer after neoadjuvant chemoradiotherapy and radical surgery]

Objective: To investigate whether protective colostomy and protective ileostomy have different impact on anastomotic leak for rectal cancer patients after neoadjuvant chemoradiotherapy (nCRT) and radical surgery. Methods: A retrospectively cohort study was conducted. Inclusion criteria: (1) Standard neoadjuvant therapy before operation; (2) Laparoscopic rectal cancer radical resection was performed; (3) During the operation, the protective enterostomy was performed including transverse colostomy and ileostomy; (4) The patients were followed up regularly; (5) Clinical data was complete. Exclusion criteria: (1) Colostomy and radical resection of rectal cancer were not performed at the same time; (2) Intestinal anastomosis is not included in the operation, such as abdominoperineal resection; (3) Rectal cancer had distant metastasis or multiple primary colorectal cancer. Finally 208 patients were included in this study. They suffered from rectal cancer and underwent protective stoma in radical surgery after nCRT at our hospital from January 2014 to December 2018. There were 148 males and 60 females with age of (60.5±11.1) years. They were divided into protective transverse colostomy group (n=148) and protective ileostomy group (n=60). The main follow up information included whether the patient has anastomotic leak and the type of leak according to ISREC Grading standard. Besides, stoma opening time, stoma flow, postoperative hospital stay, stoma related complications and postoperative intestinal flora were also collected. Results: A total of 28 cases(13.5%) suffered from anastomotic leak and 26 (92.9%) of them happened in the early stage after surgery (less than 30 days) . As for these early-stage leak, ISREC Grade A happened in 11 cases(42.3%), grade B in 15 cases(57.7%) and no grade C occurred. There was no significant difference in the incidence [12.8% (19/148) vs. 15.0% (9/60) , χ(2)=0.171, P=0.679] or type [Grade A: 5.4%(8/147) vs. 5.1%(3/59); Grade B: 6.8%(10/147) vs. 8.5%(5/59), Z=0.019, P=1.000] of anastomotic leak between the transverse colostomy group and ileostomy group (P>0.05), as well as operation time, postoperative hospital stay, drainage tube removal time or stoma reduction time (P>0.05). There were 10 cases (6.8%) and 24 cases (40.0%) suffering from intestinal flora imbalance in protective transverse colostomy and protective ileostomy group, respectively (χ(2)=34.503, P<0.001). Five cases (8.3%) suffered from renal function injury in the protective ileostomy group, while protective colostomy had no such concern (P=0.002). The incidence of peristomal dermatitis in the protective colostomy group was significantly lower than that in the protective ileostomy group [12.8% (9/148) vs. 33.3%(20/60), χ(2)=11.722, P=0.001]. Conclusions: It is equally feasible and effective for rectal cancer patients after nCRT to carry out protective transverse colostomy or ileostomy in radical surgery. However, we should pay more attention to protective ileostomy patients, as they are at high risk of intestinal flora imbalance, renal function injury and peristomal dermatitis.

Strategies for improving the emission performance of hybrid electric vehicles

Low emission vehicle technologies need widespread adoption in the transport sector to overcome its significant decarbonisation challenges. Hybrid Electric Vehicles (HEVs) represent an intermediate technology between pure electric vehicles and internal combustion engines that have proven capability in reducing petroleum consumption. HEV customers often cite improved fuel economy as a major benefit from adopting this technology; however, outstanding questions remain regarding their respective emission levels. Through an extensive literature study, we show that several issues remain with HEV emissions performance which stem from frequent high-power cold starts, engine calibration issues and inefficient operating conditions for catalytic converters. HEVs have more NO_x, HC, CO and particle number emissions compared to conventional vehicles by up to 21.0, 5.8, 9.0 and 23.3 times, respectively. Improved engine control algorithms, after-treatment design and thermal design of three-way catalysts emerge as research priorities for improving the emissions performance of HEVs.

[Prognosis and complications of local excision for rectal cancer after neoadjuvant chemoradiotherapy]

Objective: To investigate the prognosis and postoperative complications of local excision for rectal cancer after neoadjuvant chemoradiotherapy (nCRT). Methods: A descriptive case series study was carried out. Patient inclusion criteria: (1) patients who underwent local excision by transanal endoscopic microsurgery (TEM) after nCRT; (2) magnetic resonance evaluated tumor regression grade (mrTRG) as 1, 2 after nCRT;(3) American Society of Anesthesiologists class I to III. Patient exclusion criteria: (1) with multiple primary colorectal cancers; (2) with other malignant tumors within five years; (3) with emergency surgicery indications like digestive tract obstruction, perforation or bleeding. Clinicopathological and follow-up data of rectal cancer patients with obvious tumor regression after nCRT who underwent local excision in Peking Union Medical College Hospital from January 2010 to August 2019 were retrospectively collected. Outcome measures included disease-free survival (DFS), short-term postoperative complications, and at postoperative 1-year during follow up, gas continence, fecal continence, and quality of life (using the EORTC QLQ-CR29 scale, higher score indicated worse quality of life) at postoperative 1-year. Results: A total of 40 patients were included in this study. There were 27 males and 13 females with an average age of (66.7±12.3) years. Preoperative rectal ultrasound and other imaging examinations indicated that the tumor was located in the anterior wall in 16 cases, the lateral wall in 12 cases, and the posterior wall in 12 cases. The distance between the lower margin of the tumor and the anal verge was (4.3±1.2) cm before nCRT and (5.1±0.9) cm after nCRT. According to mrTRG, 31 cases were assessed as mrTRG 1 and 9 cases as mrTRG 2. All the patients received local extended excision of rectal cancer using TEM platform. A total of 19 cases(47.5%) suffered from complications within one month postoperatively. Clavien-Dindo grade I complications happened in 14 cases, grade II in 3 patients, and grade III in 2 cases, who all were healed by conservative treatment. Except that 2 patient presented severe low anterior resection syndrome (LARS) at 1 year postoperatively, no severe anal dysfunction was found in this cohort patients. EORTC QLQ CR29 scale results for quality of life showed that at 1 year after TEM excision, except taste (Z=-1.968, P=0.049), anxiety (Z=-3.624, P<0.001) and skin irritation (Z=-2.420, P=0.023) were worse than the situation before neoadjuvant therapy, there were no statistically significant differences in other assessment results between pre-operation and post-operation (all P>0.05). Postoperative pathological results indicated complete tumor regression (pTRG0) in 17 cases, moderate remission (pTRG1) in 13, and mild remission (pTRG2) in 10. During the follow-up of (49.1±29.6) months, 3 patients had local recurrence and 4 had distant metastasis (3 patients with liver metastasis and 1 patient with lung metastasis followed by liver metastasis). No death was found and the 5-year disease-free survival (DFS) was 84.3%. Conclusions: Local excision through TEM following nCRT not only can be adopted as an important means to accurately determine complete clinical remission (cCR), but also has high therapeutic value for rectal cancer patients presenting cCR or near cCR, with little impact on defecatory function and quality of life. However, the morbidity of complication of TEM excision after nCRT is relatively high and there is a risk of recurrence and metastasis. Therefore, it is still necessary to strictly select the indications of local excision.

[Clinicopathological characteristics, diagnosis, and treatment of 29 cases of signet ring cell carcinoma of the rectum and sigmoid colon]

Objective: To investigate the clinicopathological characteristics and the therapeutic effects of signet ring cell carcinoma (SRCC) of rectum and sigmoid colon. Methods: Clinical data and the follow-up information of 29 SRCC patients treated in our tertiary care center from 2008 to 2018 were retrospectively reviewed. The clinicopathological features, diagnostic and therapeutic effects, and the prognostic outcomes were analyzed. Results: Among the 29 patients, 17 were male, 12 were female. The average age was (48.7±14.3) years. Colonoscopy revealed the features of diffuse circumferential thickening of the bowel wall in 20/29 cases (69.0%), while in 9/29 cases (31.0%), endoscopic biopsies showed false negative results. Twenty-five% (4/16) and 17.6% (3/17) lesions were misdiagnosed as the inflammatory changes by endoscopic rectal ultrasonography exam and rectal MRI scan, respectively. Thirteen of the 29 patients received the neoadjuvant chemoradiotherapy (NCRT), 27 patients underwent the radical resection surgeries, and 8 underwent the postoperative radiotherapy. With a median follow-up of 38.5 (3.5-87.0) months, the cumulative 3-years overall survival (OS) rate was 54.0%, and the cumulative 3-years disease-free survival (DFS) rate was 43.0%. The OS rates of patients treated with or without NCRT (non-NCRT) were 46.2% and 69.2%, respectively, without significant difference (P>0.05). The DFS rates of patients treated with or without NCRT were 45.8% and 39.2%, respectively, without significant difference (P>0.05). Parameters including age younger than 40 years and tumor size larger than 5 cm were independent potential risk factors for shortened OS (P<0.05). Conclusions: SRCC of the rectum and sigmoid colon is a rare malignant tumor with special clinical manifestations. It is younger-onset, highly malignant and with very poor prognosis. Therefore, in-depth researches with focus upon the progress of molecular oncology are urgently needed to substantially improve the therapeutic effect of this disease.

Construction of a recombinant vaccinia virus expressing Babesia gibsoni thrombospondin-related anonymous protein and evaluation of its immunogenicity in mice

Previously, we have identified a gene encoding thrombospondin-related anonymous protein of Babesia gibsoni (BgTRAP), and have shown that the antisera raised against recombinant BgTRAP expressed in Escherichia coli inhibited the growth of parasites. In the present study, a recombinant vaccinia virus expressing the BgTRAP (VV/BgTRAP) was constructed. A specific band with a molecular mass of 80 kDa, which is similar to that of native BgTRAP on the merozoites of B. gibsoni, was detected in the supernatant of VV/ BgTRAP-infected RK13 cells. Mice inoculated with VV/BgTRAP produced a specific antiBgTRAP response. The antiserum against VV/BgTRAP showed reactivity against the native BgTRAP on parasites. These results indicated that the recombinant vaccinia virus expressing BgTRAP might be a vaccine candidate against canine B. gibsoni infection.

[Systematic evaluation of clinical trial protocols of new drugs as a cure of chronic hepatitis B]

Objective: To describe the current status of registration and design characteristics of clinical trials of new drugs for curing hepatitis B through domestic and foreign websites, so as to provide references for the follow-up clinical trials of new hepatitis B drugs. Methods: A search was conducted on the US Clinical Trials Database and the Chinese Clinical Trial Registry Center. The search date was from the establishment of the database to May 26, 2020, and the registration trials of new drugs for curing hepatitis B at home and abroad were included. Two researchers independently searched and screened the literature and extracted the data. Results: A total of 106 registered clinical trials of new drugs for curing hepatitis B were included (94 English registration websites and 12 Chinese registration websites), and the number of registrations had increased year by year. Among them, the proportion of therapeutic vaccines and core protein inhibitors were the highest, accounting for 27.4% (n = 29) and 22.6% (n = 24), respectively. The vast majority of clinical trials (n = 96, 90.6%) were in the early stages (Phase I and II). The subjects in phase I clinical trial were mainly healthy people and treated CHB patients, while the subjects in phase II clinical trial were mainly CHB patients who had achieved viral suppression after initial or post-treatment. The main evaluation indicators of Phase I clinical trials were the safety and tolerability of new drugs. The main evaluation indicators in about half of Phase II clinical trials were HBsAg negative conversion/quantitative decline. Overall, the number of clinical trials with the new design was small, accounting for 3.8% (4 / 106). There were relatively few trials of new drugs for curing hepatitis B on domestic registration websites, and the information provided was incomplete. Conclusion: The number of clinical trials of new hepatitis B drugs at home and abroad is increasing year by year, but most of them are in phase I and II, with few adopting new designs. In addition, the information integrity of the domestic website registration center needs to be improved.

[Study of thermal injury effects on human HaCaT cells under simulated microgravity environment]

Objective: To investigate the thermal injury effects on human HaCaT cells under simulated microgravity environment. Methods: The human HaCaT cells were collected and divided into simulated microgravity thermal injury (SMGTI) group, normal gravity thermal injury (NGTI) group, and normal gravity false injury (NGFI) group according to the random number table. Cells in NGTI and NGFI groups were cultured routinely in culture bottle, and cells in SMGTI group were cultured in the rotary cell culture system to simulate microgravity environment. Cells in SMGTI and NGTI groups were bathed in hot water of 45 ℃ for 10 minutes to make thermal injury model, and cells in NGFI group were bathed in warm water of 37 ℃ for 10 minutes to simulate thermal injury. At post injury hour (PIH) 12, cell morphology of 3 groups was observed under inverted phase contrast electron microscope. At PIH 2, 6, and 12, single cell suspension in the 3 groups was collected to detect the cell cycle by flow cytometer and the mRNA expressions of heat shock protein 70 (HSP70), matrix metalloproteinase 9 (MMP-9), and cysteine-aspartic protease 3 (caspase-3) by real time fluorescence quantitative reverse transcription polymerase chain reaction, and the experiments were repeated for 3 times. At PIH 2, 6, and 12, cell culture supernatant in the 3 groups was collected to detect the concentration of heparin-binding epidermal growth factor (HB-EGF) by enzyme linked immunosorbent assay method, the experiment was repeated for 3 times. The sample in each group and each time point was 3. Data were statistically analyzed with analysis of variance for factorial design, one-way analysis of variance, least significant difference test, Kruskal-Wallis H test, and Mann-Whitney U test. Results: (1) At PIH 12, cells in NGFI group showed regular shape and regular arrangement, with no cell debris. The cell shape in NGTI group was generally regular, with fewer cell debris and closer arrangement than that in NGFI group. The cells in SMGTI group showed more irregular shapes, different sizes, and dead cell debris. (2) The percentage of G1 phase cells in NGTI group was significantly higher than that in NGFI group and SMGTI group at PIH 2, respectively (P<0.05), and the percentage of G1 phase cells in NGTI group was significantly lower than that in NGFI group and SMGTI group at PIH 6 and 12, respectively (P<0.05). The percentage of G2/M phase cells in NGTI group was significantly lower than that in SMGTI group at PIH 2 (P<0.05), and the percentage of G2/M phase cells in NGTI group was significantly higher than that in NGFI group and SMGTI group at PIH 6 and 12, respectively (P<0.05). The percentage of S phase cells in NGTI group at PIH 2, 6, and 12 was significantly higher than that in SMGTI group (P<0.05), and the percentage of S phase cells in NGTI group at PIH 2 and 6 was significantly lower than that in NGFI group (P<0.05). (3) The HSP70 mRNA expressions of cells in NGTI group were 2.50±0.30 and 3.99±0.35 at PIH 2 and 6, which were significantly higher than 1.14±0.15 and 0.82±0.27 in NGFI group (P<0.05), and 1.17±0.53 and 1.65±0.59 in SMGTI group (P<0.05). The MMP-9 mRNA expression of cells in SMGTI group was significantly higher than that in NGTI group at PIH 2, 6, and 12, respectively (Z=-2.319, -2.882, -2.908, P<0.05). At each time point after injury, the mRNA expression of caspase-3 of cells in NGTI group was similar to that in NGFI group and SMGTI group, respectively (P>0.05). (4) The concentration of HB-EGF in cell culture supernatant of NGTI group was significantly lower than that in NGFI group at PIH 2, 6 and 12 (P<0.05), and the concentration of HB-EGF in cell culture supernatant of SMGTI group was significantly higher than that in NGTI group at PIH 2 and 6 (P<0.05). Conclusions: The proliferation and secretion functions and expression of wound repair related protein of human HaCaT cells inflicted with thermal injury in simulated microgravity environment showed complex and diversified changes, which provide theoretical basis for further research on damage repair under weightlessness.

[Effect of chronic hepatitis B virus DNA negative transformation and HBsAg clearance on the occurrence of hepatocellular carcinoma]

Achieving HBV DNA negative transformation and HBsAg clearance with effective antiviral therapy can reduce the incidence of HCC, but some patients are still at risk of developing HCC. Therefore, screening high-risk patients for close monitoring is essential to reduce the incidence of HCC. This paper reviews the occurrence of HCC, risk factors and risk prediction models of HBV DNA negative transformation and HBsAg clearance, and provides a basis for screening and follow-up management of high-risk group of HCC with chronic hepatitis B.

[Comparison of protective ileostomy and transverse colostomy through specimen extraction auxiliary incision following laparoscopic low anterior resection for rectal cancer]

Objective: To introduce a new technique of protective ostomy using the specimen extraction auxiliary incision following laparoscopic low anterior resection for rectal cancer, and to compare the pros and cons of loop ileostomy (LI) and loop transverse colostomy (LTC). Methods: A retrospective cohort study was performed. The data of patients who underwent laparoscopic low anterior resection for rectal cancer and ostomy using the auxiliary incision in Peking Union Medical College Hospital from January 2010 to December 2017 were retrospectively analyzed. Inclusion criteria: (1) patient underwent neoadjuvant chemoradiotherapy before operation; (2) patient was classified as tumor stage II or III; (3) patient was followed up and underwent stoma closure at our center; (4) ostomy was performed through specimen extraction incision. Patients with multiple gastrointestinal carcinomas or inflammatory bowel disease were excluded. Two hundred and eight patients were included in the study and divided into the LI group (n=86) and LTC group (n=122). The operation parameters and postoperative complications were compared between the two groups. Results: There were 135 males and 73 females (1.85∶1.00). Mean age of the 208 patients was (59.6±11.6) years (range 29-85 years). There were no significant differences between LI and LTC groups in baseline data (all P>0.05). All of the patients completed surgery successfully. The severe complication rate after ostomy was 2.9% (6/208). In the fecal diversion period, LI group showed significantly faster defecation [(1.6±1.0) days vs. (2.2±1.9) days, t=-2.918, P=0.004] and lower incidence of parastomal hernia [8.1% (7/86) vs. 19.7% (24/122), χ(2)=5.290, P=0.021], but higher incidence of peristomal dermatitis [18.6% (16/86) vs. 4.9% (6/122), χ(2)=9.990, P=0.002] as compared to LTC group. The incidence of renal insufficiency was lower in LTC group, though the difference was not significant [4.9% (6/122) vs. 10.5% (9/86), χ(2)=2.320, P=0.128]. The severe complication rate after stoma closure was 1.9% (4/208). In the stoma closure period, a significantly higher incidence of wound infection was noted in LTC group [18.0% (22/122) vs. 4.7% (4/86), χ(2)=8.258, P=0.004]. There were no significant differences between the two groups in the incidence of anastomotic leakage, stenosis, and incisional hernia (all P>0.05). All complications were improved after treatment. Conclusions: Both LI and LTC through auxiliary incision following laparoscopic low anterior resection for rectal cancer are safe and feasible. LTC is an optional method for those patients with sensitive skin.

[Effects of pulse contour cardiac output monitoring technology in amelioration of myocardial damage in fluid resuscitation of patients with large area burn in the early stage]

Objective: To analyze effects of pulse contour cardiac output (PiCCO) monitoring technology in amelioration of myocardial damage in fluid resuscitation of patients with large area burn in the early stage. Methods: From November 2015 to November 2017, medical data of 52 patients with large area burn hospitalized in our unit, meeting the inclusion criteria, were analyzed retrospectively. Twenty-seven patients (18 males and 9 females) with age of (43±10)years in tradition group hospitalized from November 2015 to November 2016 were monitored by traditional monitoring methods for fluid resuscitation, and 25 patients (18 males and 7 females) with age of (44±10)years in PiCCO group hospitalized from December 2016 to November 2017 were monitored by traditional monitoring methods and PiCCO monitoring equipment for fluid resuscitation. Fluid infusion coefficients and total fluid replacement volume of patients in both groups at the first and second post burn hour (PBH) 24, as well as the levels of N terminal pro B type natriuretic peptide (NT-proBNP), cardiac troponin T (cTnT), and creatine kinase MB (CK-MB) immediately on admission and post burn day (PBD) 1, 2, 3, 4, 5, 6, and 7 were recorded. Data were processed with analysis of variance for repeated measurement, chi-square test, t test and Bonferroni correction, and Mann-Whitney U test and Bonferroni correction. Results: (1) The fluid infusion coefficients of patients in tradition group at the first and second PBH 24 were respectively (1.42±0.10) and (0.94±0.14)mL·kg(-1)·% total body surface area (TBSA)(-1), and those in PiCCO group were respectively (1.76±0.14) and (0.85±0.08) mL·kg(-1)·%TBSA(-1). Fluid infusion coefficient and total fluid replacement volume at the first PBH 24 of patients in PiCCO group were significantly higher than those in tradition group (t=-9.775, -4.769, P<0.01). Fluid infusion coefficient at the second PBH 24 of patients in PiCCO group was significantly lower than that in tradition group (t=2.682, P<0.05). There was no statistically significant difference in total fluid replacement volume at the second PBH 24 in patients between the two groups (t=1.167, P>0.05). (2) Immediately on admission and PBD 1, 2, 3, 4, 5, 6, and 7, the levels of NT-proBNP of patients in tradition group were respectively 518 (320, 763), 236 (98, 250), 139 (62, 231), 172 (104, 185), 296 (225, 341), 727 (642, 921), 1 840 (1 357, 2 081), 1 005 (671, 1 297) pg/mL, and those in PiCCO group were respectively 444 (206, 601), 66 (29, 73), 54(28, 75), 139(101, 175), 199 (106, 279), 576 (333, 837), 833 (466, 1 080), 485 (225, 710) pg/mL. The levels of NT-proBNP of patients in PiCCO group on PBD 1, 2, 6, and 7 were significantly lower than those in tradition group (Z=-5.004, -3.967, -5.285, -4.626, P<0.01). The levels of NT-proBNP immediately on admission and PBD 3, 4, and 5 in patients between the two groups were close (Z=-0.834, -0.806, -2.665, -2.153, P>0.05). (3) Immediately on admission and PBD 1, 2, 3, 4, 5, 6, and 7, the levels of cTnT of patients in tradition group were respectively (42±15), (21±12), (17±7), (11±4), (12±4), (94±32), (88±23), (42±23) pg/L, and those in PiCCO group were respectively (37±15), (9±3), (10±3), (13±3), (12±5), (85±30), (60±26), (22±14) pg/L. The levels of cTnT of patients in PiCCO group on PBD 1, 2, 6, and 7 were significantly lower than those in tradition group (t=5.227, 4.751, 4.239, 3.845, P<0.01). The levels of cTnT immediately on admission and PBD 3, 4, and 5 of patients between the two groups were close (t=1.098, -1.562, -0.117, 1.107, P>0.05). (4) The levels of CK-MB of patients in PiCCO group on PBD 3, 6, and 7 were significantly lower than those in tradition group (t=3.123, 4.103, 3.178, P<0.05 or P<0.01). The levels of CK-MB immediately on admission and PBD 1, 2, 4, and 5 in patients between the two groups were close (t=0.351, 1.868, 1.100, 0.798, 2.094, P>0.05). Conclusions: PiCCO monitoring technology can monitor and guide fluid resuscitation of patients with large area burn in the early stage more scientifically and reasonably, and the effect of reducing myocardial damage is better than traditional monitoring methods.

[An initial exploration of the application of transanal endoscopic microsurgery in rectal cancer patients with clinical complete response after neoadjuvant chemoradiotherapy]

Objective: To preliminarily explore the value of transanal endoscopic microsurgery (TEM) in rectal cancer patients with clinical complete response (cCR) following neoadjuvant chemoradiotherapy (nCRT). Methods: Using descriptive case series method, Clinical data of 13 patients who met the criteria of nCRT and were considered to be cCR after MRI or CT scanning, digital rectal examination and colonoscopic biopsy, as well as no lymph node or distant metastasis were found, then underwent TEM from 2013 to 2016 at the Department of General Surgery of Peking Union Medical College Hospital were collected retrospectively. A 3-course combination of capecitabine and oxaliplatin (XELOX) was used for chemotherapy. Besides, a 6MV-X ray radiation was used as radiotherapy simultaneously. Six to eight weeks after completion of radiotherapy, a preoperative assessment was carried out with intrarectal ultrasound, MRI, or pelvic abdominal CT examination. TEM was performed afterwards with informed consent. Postoperative pathological findings and follow-up results were used to evaluate the value of diagnosis and treatment of TEM on those patients. Results: There were 8 males and 5 females with a median age of 63 (27-80) years. Preoperative examination showed that the lesions were located in the anterior wall in 3 cases, the posterior wall in 3 cases, the left side wall in 4 cases, and the right side wall in 3 cases. Before nCRT, the distance between tumor and anal margin was (4.8±1.1) (2.0-7.5) cm; after nCRT, this distance was (5.2±1.3) (3.0-7.5) cm. All the 13 patients underwent extended local resection of rectal cancer via TEM with the placement of urethral catheter. The average operative time was (52.2±3.7) (42-70) minutes, and the average intraoperative blood loss was (19.2±2.8) (5-30) ml. All the patients could engage in daily activities on postoperative day 1, and could cater themselves orally on postoperative day 2. The main discomfort was postoperative anal pain and foreign body sensation (n=5), which could be alleviated by non-steroidal anti-inflammatory drugs. One case had postoperative lung infection and was cured by antibiotic treatment. One case had urinary retention after removing urine catheter, and then a urine catheter was re-inserted. Average postoperative hospital stay was (2.8±2.4) (2-12) days. All specimens were completely resected via TEM. Histopathological examination confirmed that 7 specimens had achieved pathologic complete response (pCR) and the other 6 specimens had obtained partial tumor response of CAP grade 2. Seven patients with pCR received a median follow-up of 24 (8-48) months and no local recurrence or distant metastasis was reported during follow-up period. Among these 7 cases, one developed defecation dysfunction after discharge, mainly for defecation pain and even dare to defecate, who returned to normal defecation within 2 months after surgery; One developed severe anal pain within six months after surgery and the pain disappeared after symptomatic pain relief. The other 6 patients with CAP grade 2 refused to undergo further radical operation because of their strong desire in preserving anus, and received remedial adjuvant chemotherapy instead. Conclusion: For rectal cancer patients with cCR after nCRT, TEM does have certain application values if the patient has a strong desire to preserve anus.

[Advances in the research of application of pulse contour cardiac output monitor technology in patients with large area of burns]

Pulse contour cardiac output (PiCCO) monitor as an invasive monitoring technology has been widely applied to various kinds of critical patients. It can reliably reflect actual hemodynamics of critical patients and monitor parameters such as cardiac output. Fluid resuscitation is of great importance for patients with large area of burns. On account of its easy operation as well as precise and comprehensive parameters, PiCCO has been widely used in circulation monitoring of patients with large area of burns. This article briefly introduces PiCCO monitor technology and reviews its application in fluid resuscitation monitoring, diagnosis and identification of pneumonedema in patients with large area of burns, as well as the new theory and knowledge.

[Qualitative pathological assessment of liver fibrosis regression after antiviral therapy in patients with chronic hepatitis B]

Objective: To investigate the methods for qualitative pathological assessment of dynamic changes in liver fibrosis/cirrhosis after antiviral therapy in patients with chronic hepatitis B (CHB), since antiviral therapy can partially reverse liver fibrosis and cirrhosis caused by hepatitis B and semi-quantitative, rather than qualitative, pathological assessment is often used for the research on liver fibrosis regression. Methods: Previously untreated CHB patients with liver fibrosis and cirrhosis were enrolled, and liver biopsy was performed before treatment and at 78 weeks after the antiviral therapy based on entecavir. The follow-up assessment was performed once every half a year. Based on the proportion of different types of fibrous septum, we put forward the new qualitative criteria called P-I-R classification (predominantly progressive, predominantly regressive, and indeterminate) for evaluating dynamic changes in liver fibrosis. This classification or Ishak fibrosis stage was used to evaluate the change in liver fibrosis after treatment and Ishak liver inflammation score was used to evaluate the change in liver inflammation after treatment. Results: A total of 112 CHB patients who underwent liver biopsy before and after treatment were enrolled, and among these patients, 71 with an Ishak stage of ≥3 and qualified results of live biopsy were included in the final analysis. Based on the P-I-R classification, 58% (41/71) were classified as predominantly progressive, 29% (21/71) were classified as indeterminate, and 13% (9/71) were classified as predominantly regressive; there were no significant differences between the three groups in alanine aminotransferase, aspartate aminotransferase, albumin, HBeAg positive rate, HBV DNA, and liver stiffness (P < 0.05). After treatment, the proportion of predominantly progressive, indeterminate, or predominantly regressive patients changed to 11% (8/71), 11% (8/71), and 78% (55/71), respectively. Among the 35 patients who had no change in Ishak stage after treatment, 72% (25/35) were classified as predominantly regressive and had certain reductions in the Laennec score, percentage of collagen area, and liver stiffness. Conclusion: This new P-I-R classification can be used to assess the dynamic changes in liver fibrosis after antiviral therapy in CHB patients.

[A machine learning model on orthokeratology lens fitting based on the data of optometry examination]

Objective: To get an orthokeratology lens fitting model according to the research of the optometry examination data, which can help to improve the work efficiency and increase the hitting rate of prescription. Methods: The relationship between the basic optometry examination data and the effective optometry prescription was evaluated. We got 1 467 sets of data, including 80%(1 173) for training and 20%(294) for testing. The trail results were used for the 20% testing sets, and 100% completed sets for verification. With the contrast of accuracy, we got the influencing variables and the fitting model. Logistic regression and linear regression analysis were applied to the training set for building a fitting model, and the receiver operating characteristic curve (ROC curve) was drawn to determine the optimal threshold of the logistic regression model (1.0).The trail results are used for the 20% testing sets, 100% completed sets for verification. With the contrast of accuracy (ACC), we get the influencing variables and the fitting model. Results: Kf-FK and Ks-SK were selected as dependent variables. Through analysis of Stepwise regression, we found the influencing variables of Kf-FK were Kf(P=0.01), E(mean) (P=0.027), and CYL(P<0.001), with FK=6.23+0.866kf-1.69 E(mean)+0.16CYL, and the precision rate was 81%(r(2)=0.95). The influencing variables of Ks-SK were Ks (P<0.001), CYL (P=0.00), and E(mean) (P<0.001), with SK=6.84+0.862ks-0.28E(mean)-1.3CYL, and the precision rate was 80%(r(2)=0.93). By selecting the logistic method and decision tree analysis for glasses design, the influencing variables were KS (P<0.001)and CYL (P<0.001). The logistic function was Design=-45.7+0.82Ks+6.027CYL, and the precision rate was 87%. Conclusions: The combination of AI and medical data can verify the expert experience and guide the optometrist to locate the prescription quickly and accurately. Try to break the traditional mode of fitting with wearing the orthokeratology lens shortly, and it is possible for us to position the prescription quickly through the calculation of a computer. (Chin J Ophthalmol, 2019, 55: 105-110).

[An analysis of intraocular metallic foreign body injury during hammer percussion]

Objective: To investigate the cause of intraocular metallic foreign body injury during hammer percussion and to observe the structure of the metallic foreign bodies. Methods: A retrospective analysis was performed in 21 inpatients with metallic foreign body injury in the posterior segment from January 2013 to April 2016. The foreign bodies were removed by magnetic drawing through external route of the sclera or vitrectomy. The shape of the foreign bodies was analyzed and the structural characteristics were observed under a metallurgical microscope. The visual acuity of the patients was compared before and after treatment. Results: All patients were discharged at one week after surgery. There was no significant difference in mean best corrected visual acuity of the patients between before treatment and after treatment (1.20±0.87 vs. 1.08±0.89, t=1.516, P>0.05). The metallic foreign bodies in all the 21 cases were magnetic and the injuries in 15 cases (71.43%) were caused by hammering on hard objects. The foreign bodies were mainly lamellar and shaped like a leaf or a lance. And the lamellar martensite structure was observed under a metallurgical microscope. Conclusion: The intraocular metallic foreign body injury often occurs during hammer percussion and the microstructure of the foreign bodies is lamellar martensite structure.

Bioprocessing for elimination antibiotics and hormones from swine wastewater

Antibiotics and hormones in swine wastewater have become a critical concern worldwide due to the severe threats to human health and the eco-environment. Removal of most detectable antibiotics and hormones, such as sulfonamides (SAs), SMs, tetracyclines (TCs), macrolides, and estrogenic hormones from swine wastewater utilizing various biological processes were summarized and compared. In biological processes, biosorption and biodegradation are the two major removal mechanisms for antibiotics and hormones. The residuals in treated effluents and sludge of conventional activated sludge and anaerobic digestion processes can still pose risks to the surrounding environment, and the anaerobic processes' removal efficiencies were inferior to those of aerobic processes. In contrast, membrane bioreactors (MBRs), constructed wetlands (CWs) and modified processes performed better because of their higher biodegradation of toxicants. Process modification on activated sludge, anaerobic digestion and conventional MBRs could also enhance the performance (e.g. removing up to 98% SMs, 88.9% TCs, and 99.6% hormones from wastewater). The hybrid process combining MBRs with biological or physical technology also led to better removal efficiency. As such, modified conventional biological processes, advanced biological technologies and MBR hybrid systems are considered as a promising technology for removing toxicants from swine wastewater.

Sediment and salinity effects on the bioaccumulation of sulfamethoxazole in zebrafish (Danio rerio)

The dynamic distribution of a widely used antibiotic sulfamethoxazole between water, sediment and aquatic organisms (zebrafish) was studied in microcosms. Sulfamethoxazole concentrations in water were gradually reduced, while in sediment and zebrafish gradually increased, suggesting active adsorption and bioaccumulation processes occurring. The presence of sediment particles and their interactions with water reduced the bioaccumulation of sulfamethoxazole in zebrafish by 13-28%. The sediment of smaller particle size with more organic carbon content and higher surface area, adsorbed sulfamethoxazole more extensively and decreased its bioaccumulation most significantly. The effect became more severe with increasing salinity in water due to the salting out of sulfamethoxazole, resulting in 24-33% reduction in bioaccumulation. At equilibrium, the distribution of sulfamethoxazole in different phases was quantified, with most sulfamethoxazole being associated with water (97.3%), followed by sedimentary phase (2.7%) and finally zebrafish (0.05%). The findings provided important data for further research into antibiotics fate and bio-uptake in aquatic organisms, and subsequent ecotoxicity.

Comparison of outcomes between off-pump versus on-pump coronary artery bypass surgery in elderly patients: a meta-analysis

The aim of this study was to analyze if off-pump coronary artery bypass surgery (CABG) is associated with better treatment outcomes in elderly patients (>70 years of age) than on-pump CABG, using meta-analysis. Medline, PubMed, Cochrane and Google Scholar databases were searched until September 13, 2016. Sensitivity and quality assessment were performed. Twenty-two studies, three randomized control trials (RCTs) and 20 non-RCTs were included with 24,127 patients. The risk of death associated with on-pump or off-pump CABG in the RCTs were similar (pooled OR=0.945, 95%CI=0.652 to 1.371, P=0.766). However, in the non-RCTs, mortality risk was lower in patients treated with off-pump CABG than on-pump CABG (pooled OR=0.631, 95%CI=0.587 to 0.944, P=0.003). No differences were observed between the two treatment groups in terms of the occurrence of 30-day post-operative stroke or myocardial infarction (P≥0.147). In the non-RCTs, off-pump CABG treatment was associated with a shorter length of hospital stay (pooled standardized difference in means=-0.401, 95%CI=-0.621 to -0.181, P≤0.001). The meta-analysis with pooled data from non-RCTs, but not RCTs, found that mortality was lower with off-pump compared with on-pump CABG, and suggested that there may be some benefit of off-pump CABG compared with on-pump CABG in the risk of mortality and length of hospital stay.

Persistence and risk of antibiotic residues and antibiotic resistance genes in major mariculture sites in Southeast China

Antibiotics are widely used in mariculture industry, and this study attempts to determine the extent of water and sediment pollution by antibiotic residues in 13 major mariculture sites in China. Through chemical and molecular biology analysis, the results showed that the total concentrations of sulfonamides and tetracyclines were in the range 62.0-373.8ngL^-1 and 0.2-259.1ngL^-1 respectively in water samples, and in the range 0.19-1.59ngg^-1 dry weight and 3.45-74.84ngg^-1 dry weight respectively, in sediments samples. The occurrence of antibiotic resistance genes (ARGs) was detected in all sites. Compared with the tetracyclines resistance genes, the absolute copy number and relative abundance of the sulfonamides resistance genes were 4.3 times and 2.3 times higher in water and sediment from the mariculture sites, with the dominant resistance genes being sul2. The abundance of sul3 in the water phase was significantly correlated with the concentrations of sulfamerazine, while the abundance of sul2 in the sediment phase was significantly with sulfadiazine concentrations. The abundance of tetM in the sediment phase was significantly correlated with the concentrations of oxytetracycline. The findings demonstrate the persistence of antibiotic residues and ARGs in major mariculture sites in Southeast China.

[A discussion of the methods for the assessment of chronic hepatitis B-related liver fibrosis regression]

Antiviral therapy could reverse hepatitis B-related liver fibrosis and early-stage cirrhosis. However, the assessment of fibrosis regression remains controversial. As the gold standard for assessment, liver biopsy has its own limitations. In terms of non-invasive assessment, there are many interfering factors for transient elastography and less clinical evidence for the use of serum markers. Therefore, further evidence from clinical studies is still needed to determine the role of non-invasive methods in evaluating fibrosis regression.

Comparing the value of bioproducts from different stages of anaerobic membrane bioreactors

The anaerobic digestion process in anaerobic membrane bioreactors is an effective way for waste management, energy sustainability and pollution control in the environment. This digestion process basically involves the production of volatile fatty acids and biohydrogen as intermediate products and methane as a final product. This paper compares the value of bioproducts from different stages of anaerobic membrane bioreactors through a thorough assessment. The value was assessed in terms of technical feasibility, economic assessment, environmental impact and impact on society. Even though the current research objective is more inclined to optimize the production of methane, the intermediate products could also be considered as economically attractive and environment friendly options. Hence, this is the first review study to correlate the idea into an anaerobic membrane bioreactor which is expected to guide future research pathways regarding anaerobic process and its bioproducts.

Sensitization of suberoylanilide hydroxamic acid (SAHA) on chemoradiation for human cervical cancer cells and its mechanism

PURPOSE

To explore the sensitization of suberoylanilide hydroxamic acid (SAHA) on chemoradiation for cervical cancer cells and its mechanism.

MATERIALS AND METHODS

After human cervical cancer SiHa cells were treated with SAHA and cisplatin (DDP) of different concentrations, inhibition and apoptosis rates, and cell cycle were detected. SiHa cells underwent radiation of various doses after treated with 20% IC50 of SAHA for 24 hours. The survival fraction of SiHa cells was calculated by colony-forming assay, and related parameters were calculated. mRNA and protein expressions of P21, Bax and Ku70 were detected.

RESULTS

The inhibition rate was higher in SD (SAHA combined with DDP) group than in D (DDP alone) group (p < 0.05). The number of cells in G0/G1 phase was higher, and the number of cells in G2/M+S phase and PI (proliferation index) were lower in S (SAHA), D, and SD groups than in control group, and in SD group than in S and D groups (p < 0.05). The apoptosis rate and the expressions of mRNA and protein of Bax and P21 were higher in SD group than in S or D group (p < 0.05). The cell survival fraction was lower in SAHA combined with radiotherapy group than in radiotherapy alone group (p < 0.05). Do, N, and Dq values were 2.329, 2.761, and 1.721, respectively, in radiotherapy alone group and 1.213, 4.770, and 0.823, respectively, in SAHA combined with radiotherapy group. SER was 1.92. Bax mRNA and protein expressions were higher but Ku70 mRNA and protein expressions were lower in SAHA combined with radiotherapy group than in radiotherapy alone group (p < 0.05).

CONCLUSION

SAHA promotes SiHa apoptosis in chemotherapy through up-regulation of mRNA and protein of p21 and Bax which leads to cell cycle arrest in G0/G1 phase. Low dose of SAHA promotes SiHa apoptosis and inhibits cell repair in radiotherapy through Bax up-regulation and Ku70 down-regulation.

Phosphorus elimination from aqueous solution using 'zirconium loaded okara' as a biosorbent

This work deals with the capture of phosphorus from aqueous solutions by biosorption onto zirconium loaded okara (ZLO). The batch-mode experiments were conducted to examine the effect of pH, biosorbent dose, initial phosphorus concentration, contact time, and temperature on the process. It was found that, the adsorption was most favored in the pH range of 2-6. The optimal doses for the adsorption, at initial phosphorus concentrations of 5, 10, 25, 50mg/L were 2, 3, 7, 10g/L, respectively. The maximum adsorption capacity of ZLO was approximately 44.13mg PO4/g at 298K. The phosphate removal was rapid, reaching 95% in 30min. Freundlich model best fitted the equilibrium data, while Pseudo-second order model satisfactorily described the kinetic results. Thermodynamic analysis revealed feasible, spontaneous, and endothermic nature of the process. The research would be beneficial for developing a promising, eco-friendly phosphorus biosorbent from a plentiful AWB - okara.

Application of passive sampling in assessing the occurrence and risk of antibiotics and endocrine disrupting chemicals in the Yangtze Estuary, China

Polar organic chemical integrative sampler (POCIS) was used in assessing the occurrence and risk of 12 widely used antibiotics and 5 most potent endocrine disrupting chemicals (EDCs) in the Yangtze Estuary, China. During laboratory validation, the kinetics of pollutant uptake by POCIS were linear, and the sampling rates of most compounds were raised by flow rate and salinity, reaching the highest values at salinity 14‰. The sampling rates varied with the target compounds with the EDCs showing the highest values (overall average=0.123Ld(-1)), followed by chloramphenicols (0.100Ld(-1)), macrolides (0.089Ld(-1)), and finally sulfonamides (0.056Ld(-1)). Validation in the Yangtze Estuary in 2013 showed that the field sampling rates were significantly greater for all compounds except bisphenol A, in comparison to laboratory results, and high-frequency spot sampling is critical for fully validating the passive sampler. The field studies show that antibiotics were widely detected in the Yangtze Estuary, with concentrations varying from below quantification to 1613ngL(-1), suggesting their widespread use and persistence in estuarine waters. The dominating pollutants in July were sulfonamides with a total concentration of 258ngL(-1) and in October were macrolides with a total concentration of 350ngL(-1). The calculation of risk quotient suggested that sulfapyridine, sulfaquinoxaline and erythromycin-H2O may have caused medium damage to sensitive organisms such as fish.

A laparoscopic approach to benign retrorectal tumors

BACKGROUND

Retrorectal tumors (RTs) are rare in adults. Their surgical excision is often difficult because of their anatomic location. The aim of this study was to evaluate the results of straight laparoscopic resection of RTs in our institution.

METHODS

Eight patients (six women and two men) with benign RTs were treated by laparoscopic resection in our tertiary care center between September 2012 and June 2013. Exclusion criteria included malignant tumors, lesions with fistula formation, and anterior sacral meningoceles. Clinical data, imaging features, operative details, pathological results, and treatment outcomes were reviewed and analyzed.

RESULTS

Eight cases of benign RT with an average diameter of 8.9 ± 1.7 cm were treated by a straight laparoscopic procedure. The mean operative time was 122 ± 36 min, and the average intraoperative blood loss was 46 ± 33 ml. The median postoperative stay was 5 days (range 3-8 days), and all patients were discharged without serious complications. During a median follow-up of 11 months, no tumor recurrence was observed.

CONCLUSIONS

In our experience, a laparoscopic approach is safe for removing benign tumors in the retrorectal space. This approach may provide access to this difficult-to-reach space and has the advantages of allowing excellent visualization, meticulous dissection, less morbidities, and fast recuperation.

Stability of Fe-oxide nanoparticles coated with natural organic matter under relevant environmental conditions

Manufactured nanoparticles (MNPs) are increasingly released into the environment and thus research on their fate and behaviour in complex environmental samples is urgently needed. The fate of MNPs in the aquatic environment will mainly depend on the physico-chemical characteristics of the medium. The presence and concentration of natural organic matter (NOM) will play a significant role on the stability of MNPs by either decreasing or exacerbating the aggregation phenomenon. In this study, we firstly investigated the effect of NOM concentration on the aggregation behaviour of manufactured Fe-oxide nanoparticles. Then, the stability of the coated nanoparticles was assessed under relevant environmental conditions. Flow field-flow fractionation, an emerging method which is gaining popularity in the field of nanotechnology, has been employed and results have been compared to another size-measurement technique to provide increased confidence in the outcomes. Results showed enhanced stability when the nanoparticles are coated with NOM, which was due to electrosteric stabilisation. However, the presence of divalent cations, even at low concentration (i.e. less than 1 mM) was found to induce aggregation of NOM-coated nanoparticles via bridging mechanisms between NOM and Ca(2+).

Occurrence and behavior of antibiotics in water and sediments from the Huangpu River, Shanghai, China

This study aims to determine the occurrence and behavior of five classes of 20 antibiotics in both water and sedimentary phases in the Huangpu River, which supplies drinking water to Shanghai City, China. Of the 20 antibiotics, sulfonamides showed the highest concentrations in water samples (34-859 ng L(-1)) while tetracyclines (average concentration at 18 μg kg(-1) dry weight) and macrolides (12 μg kg(-1) dry weight) dominated in sediment samples. The spatial distribution of antibiotics showed that the main polluting sources into the river were animal farming sites and the tributaries downstream of the Yuanxie River. In addition, linear relationships between logKoc and logKow, and between logKoc and log molecular weight, were demonstrated, suggesting the importance of contaminant properties in inter-phase behavior. The environmental risk assessment revealed that some antibiotics, in particular sulfamethoxazole could cause medium damage to daphnid in the aquatic ecosystem.

Endocrine disrupting activities in sewage effluent and river water determined by chemical analysis and in vitro assay in the context of granular activated carbon upgrade

As part of endocrine disruption in catchments (EDCAT) programme, this work aims to assess the temporal and spatial variations of endocrine disrupting chemicals (EDCs) in River Ray, before and after the commissioning of a full-scale granular activated carbon (GAC) plant at a sewage treatment works (STW). Through spot and passive sampling from effluent and river sites, estrogenic and anti-androgenic activities were determined by chemical analysis and in vitro bio-assay. A correlation was found between chemical analyses of the most potent estrogens (estrone (E1), 17β-estradiol (E2), 17α-ethinylestradiol (EE2)) and yeast estrogen screen (YES) measurement, both showing clearly a reduction in estrogenic activity after the commissioning of the GAC plant at the STW. During the study period, the annual average concentrations of E1, E2 and EE2 had decreased from 3.5 ng L(-1), 3.1 ng L(-1) and 0.5 ng L(-1) to below their limit of detection (LOD), respectively, with a concentration reduction of at least 91%, 81% and 60%. Annual mean estrogenic activity measured by YES of spot samples varied from 1.9 ng L(-1) to 0.4 ng L(-1) E2 equivalent between 2006 and 2008 representing a 79% reduction. Similarly, anti-androgenic activity measured by yeast anti-androgen screen (anti-YAS) of spot samples was reduced from 148.8 to 22.4 μg flutamide L(-1), or by 85%. YES and anti-YAS values were related to each other, suggesting co-existence of both types of activities from chemical mixtures in environmental samples. The findings confirm the effectiveness of a full-scale GAC in removing both estrogenic and anti-androgenic activities from sewage effluent.

Occurrence and phase distribution of selected pharmaceuticals in the Yangtze Estuary and its coastal zone

The occurrence and geochemical behavior of nine pharmaceutical compounds were investigated along the Yangtze River Estuary and its coastal area, by sampling and analysis of pharmaceuticals in sediment, suspended particulate matter (SPM), colloidal and soluble phases. In addition, the impact of sewage input was examined by sampling from sewage treatment plants (STP) effluent and its upstream and downstream in the Yangtze River. Although at relatively low concentrations in SPM and sediments, several pharmaceuticals were found at elevated concentration in filtered water samples from STP-affected sites. STP is therefore an important input of pharmaceuticals in the study area. Colloidal phase was further separated from bulk water samples using cross-flow ultrafiltration (CFUF), confirming it being an effective sorbent for pharmaceuticals with high sorption capacity which are 2-4 orders of magnitude higher than SPM. Moreover, mass balance calculations showed that significant percentages of selected pharmaceutical compounds were associated with aquatic colloids, indicating colloids as a reservoir for these contaminants in the Yangtze estuarine system.

The first vitellogenin receptor from a Lepidopteran insect: molecular characterization, expression patterns and RNA interference analysis

The vitellogenin receptor (VgR) belongs to the low-density lipoprotein receptor (LDLR) superfamily, and is an important carrier for the uptake of vitellogenin (Vg) into developing oocytes of all oviparous species. The first full-length message for a VgR from a Lepidopteran insect was cloned and sequenced from the ovary of Spodoptera litura Fabricius (GenBank accession no. GU983858). The coding region consisted of 5370 bp flanked by a 49 bp 5'-untranslated region (UTR) and a 177 bp 3'-UTR, which encoded a 1798-residue protein with a predicted molecular weight (MW) of 201.69 kDa. S. litura VgR (SlVgR)comprised two ligand binding sites with four LDLR class A repeats in the first domain and seven in the second domain, an epidermal growth factor-like domain containing an LDLR class B repeat and a YWXD motif, a transmembrane domain and a cytoplasmic domain. A phylogenetic relationship placed SlVgR as a separate group from the other insects. SlVgR messenger RNA (mRNA) was specifically expressed in the ovarian tissues. The developmental expression patterns showed that VgR mRNA was first transcribed in 6(th) day female pupae and the maximum level of VgR mRNA appeared in 36-h-old adults. Immunoblot analysis detected an ovary-specific VgR protein with a MW of ∼200 kDa, whose development profiles were consistent with VgR mRNA expression patterns. RNA inteference (RNAi) specifically disrupted the VgR gene by injection of 3 or 5 µg VgR double-stranded RNA per insect in 4(th) or 6(th) day pupae. RNAi of SlVgR led to a phenotype characterized by high Vg accumulation in the haemolymph, low Vg deposition in the ovary and the failure of insect spawning. These results mean that VgR is critical for binding Vg and transporting it into the oocytes of the insect ovary, thus playing an important role in insect reproduction.

Improved removal of estrogenic and pharmaceutical compounds in sewage effluent by full scale granular activated carbon: impact on receiving river water

Sewage effluents are widely recognised as the main source of emerging contaminants, such as endocrine disrupting chemicals (EDCs) and pharmaceuticals in surface waters. A full-scale granular activated carbon (GAC) plant has been installed as an advanced technology for the removal of these contaminants, in a major sewage treatment works (STW) in South-West England as part of the UK National Demonstration Programme for EDCs. This study presented for the first time, an assessment of the impact of a recently commissioned, post-tertiary GAC plant in the removal of emerging contaminants in a working STW. Through regular sampling followed by solid-phase extraction and analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS), a significant reduction in the concentrations of steroidal estrogens was observed (>43-64%). In addition, significant reductions were observed for many of the pharmaceutical compounds such as mebeverine (84-99%), although the reduction was less dramatic for some of the more widely used pharmaceuticals analysed, including carbamazepine and propranolol (17-23%).

Profiles of polycyclic aromatic hydrocarbons and polychlorinated biphenyls from the combustion of biomass pellets

An investigation was made into the emissions of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) as well as inorganic gases (e.g. CO) from a wood fired combustion boiler using wood pellets, under two different boiler operating modes. Levels of total PAHs varied from 6.4 and 154 microg m(-3), and were found to be dominating in the gas phase (>80%), regardless of pellet type and boiler operating mode. In addition to this, PAH concentrations were higher in slumber mode than in full flame, and increased with the moisture content of pellets, consistent with the lower combustion efficiency in slumber mode (58.6-64.3%) than in full flame (74.4-82.3%). PAHs in the gas phase comprised mainly of low molecular mass compounds, while PAHs in the particulate phase were mostly composed of high molecular mass compounds, consistent with the physicochemical properties of such compounds. In comparison to PAHs, significantly lower concentrations of PCBs (a maximum of 2.5 microg m(-3)) were released from pellet combustion, consistent with the virgin nature of the pellets. The PCBs in both the gas and particulate phases were dominated by hexachlorinated congeners, although congeners with more chlorine substitution were more abundant in the particulate phase than in gas phase. Significant relationships were established between CO and organic pollutants, and between PAHs and PCBs, which are useful tools for prediction purposes.

Pharmaceutical residues in wastewater treatment works effluents and their impact on receiving river water

Various pharmaceutical residues are being discharged from wastewater treatment works (WTW) effluents, the impact of which on river water quality is of high relevance to environmental risk assessment. The concentrations of eleven pharmaceutical compounds were determined in three WTWs in England, and the river Ouse receiving effluents from Scaynes Hill WTW. Results show that five compounds propranolol, sulfamethoxazole, carbamazepine, indomethacin and diclofenac were detected in all wastewater and river water samples, with carbamazepine showing the highest concentrations (up to 2336 ng L(-1)) in WTW influent. Different compounds were removed to different extent in the WTWs, varying from 43 to 92%, with the highest performance obtained by the WTW with tertiary treatment (sand filtration). The pharmaceutical residues from Scaynes Hill WTW were eventually discharged into the river Ouse, causing an elevation in their concentrations downstream of the outfall. This was confirmed by the good agreement between measured concentrations and those predicted by a simple dilution model.

Simultaneous determination of various pharmaceutical compounds in water by solid-phase extraction–liquid chromatography–tandem mass spectrometry

A solid-phase extraction (SPE) followed by liquid chromatography-electrospray ionisation tandem mass spectrometry (LC-ESI-MS-MS) method was developed and validated for simultaneous analysis of 11 pharmaceutical residues (propranolol, sulfamethoxazole, meberverine, thioridazine, carbamazepine, tamoxifen, mecoprop, indomethacine, diclofenac, meclofenamic acid and monensin) in environmental water samples. The collision energy chosen for the multiple reaction monitoring (MRM) experiment was optimised. A number of parameters that may affect the recovery of the pharmaceuticals, such as the type of SPE cartridges, eluents, as well as water properties including pH value, salinity and concentration of colloid and surfactant were investigated. It is shown that the Oasis HLB SPE cartridge produced the best recoveries of the target pharmaceuticals while methanol was efficient in eluting pharmaceuticals from SPE cartridges. The recovery of some target compounds was enhanced with increasing salinity, but reduced by increasing pH value, and unaffected by surfactant concentration (0-10 microg/l). The recovery of most compounds was slightly increased by the presence of colloids (0-10 mg/l), which however caused a reduction in recovery for sulfamethoxazole and meberverine. The optimised method was further verified by performing spiking experiments in river water and seawater matrices, with good recovery and reproducibility for all except two compounds. The established method was successfully applied to environmental water samples from East Sussex, UK, for the determination of the target pharmaceuticals.

Sorption of selected endocrine disrupting chemicals to different aquatic colloids

The sorption of seven endocrine disrupting chemicals (EDCs) to aquatic colloids was determined by cross-flow ultrafiltration (CFUF) followed by gas chromatography-mass spectrometry (GC-MS). Results show that the colloidal organic carbon normalized sorption coefficient (Kcoc) of EDCs to different aquatic colloids varies by a factor of 6-12 because such colloids are of different origin. Through characterization of colloidal samples, a significant relationship was established between Kcoc values and the molar extinction coefficient of colloids at 280 nm, whereas no other colloidal properties such as elemental ratios were correlated with Kcoc values. The results are consistent with other reports of the importance of the quality of sorbents such as their aromatic carbon content in sorbing various organic pollutants. The presence of a surfactant was found to increase Kcoc values for estrone (El) and 17alpha-ethynylestradiol (EE2). The method was subsequently applied for determining EDC concentrations in field samples, where both conventional and truly dissolved EDCs showed higher concentrations close to sewage outfalls than either upstream or downstream, confirming the sourceconcentration relationship. In addition, the truly dissolved EDC concentrations were lower than the conventional dissolved concentrations, confirming that there were interactions between aquatic colloids and EDCs. It is estimated that between 10 and 29% of EDCs are associated with aquatic colloids. As colloids are highly abundant in rivers and ocean, they will therefore play a significant role in the environmental behavior and fate of EDCs.