[Spectroscopic characteristics of different molecular weight dissolved organic matter in water from Yangtze River estuary].

Cross flow ultrafiltration systems and three dimensional fluorescence spectrum were used to investigate the fluorescence characterization of different molecular weight dissolved organic matter in water of wet season and dry season from Yangtze River estuary, in order to find out the sources and influencing factors. The results showed that four types of dissolved organic carbon (DOM) fluorescence peaks were observed in the water: humic-like fluorescence peak A and C, and protein-like fluorescence peak B and D. Fluorescent substances mainly existed in the truly dissolved organic matter (UOM, < 1 kDa), secondly in low and medium molecular weight of colloidal organic matter (1-500 kDa). Protein of DOM in water mainly originated from anthropogenic sources, then from autochthonous sources. Compared to protein, humic acid of DOM in wet season was both terrigenous and autochthonous sources, while in dry season mainly from terrestrial organic matter. In addition, humic acid in UOM was mainly derived from biological decomposition, however, in colloidal organic matter (COM) came from terrestrial organic matter and was affected by resuspension effects. There was linear correlation between fluorescence intensity and environmental parameters. It was revealed that the complex environmental conditions would influence the fluorescent substance of DOM in water from Yangtze River estuary.

Clinical benefits of scarless endoscopic thyroidectomy: an expert's experience.

BACKGROUND: By comparison with the conventional surgical approach to thyroidectomy, scarless (in the neck) endoscopic thyroidectomy (SET) has a superior cosmetic result but a very long learning curve. The objective of the present study was to compare surgical outcomes of SET performed by an experienced surgeon with the outcomes of conventional thyroidectomy. METHOD: Enrolled in this study were 25 patients who underwent SET and 18 who underwent conventional surgery. Differences in size of tumor, length of incision, duration of operation, volume of blood loss, pathological findings, postoperative pain, complications, and cosmetic result were investigated. RESULTS: The two groups were well matched. The total length of incisions and volume of blood loss of SET were significantly lower than those of conventional surgery. In addition to the superior cosmetic result, postoperative pain was significantly less severe and rates of hypesthesia or paresthesia and discomfort while swallowing were significantly lower in the endoscopy group. CONCLUSIONS: In experienced hands, SET offers more benefits than the conventional approach, including less postoperative pain and discomfort and a better cosmetic outcome.

Laparoscope-assisted creation of a neovagina using pedicled ileum segment transfer.

BACKGROUND: To present our experience of vaginal reconstruction with the use of a pedicled ileum segment and laparoscope assistance, and to analyze its complications and long-term anatomic and functional results. METHODS: The abdominal and perineal approaches were performed simultaneously with the patient in a special position. Under the guidance of laparoscopy, the target ileal segment was harvested and transposed down to the perineum through an artificial tunnel between the bladder and the rectum. A silicon vaginal tutor was introduced into the vaginal cavity and maintained all day long for 2-3 months. The complications and the anatomical and functional results were summarized and analyzed. RESULTS: From February 2002 to June 2010, 82 patients underwent laparoscope-assisted total vaginal reconstruction with a pedicled ileum segment at our department. Complications developed in 16 of 82 patients, including rectum and/or bladder injury during operation, acute renal failure, delayed healing of the ileocutaneous anastomosis, introital stenosis, and partial or complete intestinal obstruction. The abdominal cutaneous scar was acceptable after the surgery. The vulva was not altered, which was especially significant for patients with congenital vaginal atresia. The neovagina was patent, soft, moist, and flexible. The mean width and depth of the neovagina at the latest postoperative visit measured 3.2 and 15 cm, respectively. CONCLUSIONS: The favorable long-term anatomical and functional results demonstrate that our technique is ideal for patients with congenital vaginal atresia or patients who need secondary vaginal reconstruction. For the primary male-to-female transsexuals or hermaphrodites, it can be an alternative method for vaginal construction.

New technique for retraction of the strap muscles in endoscopic thyroidectomy.

OBJECTIVE: It is extremely important to establish sufficient exposure and room for manipulation during endoscopic thyroidectomy. To solve this problem, the authors have developed a new technique for retraction of the strap muscles perfected during 500 cases of breast-approach endoscopic thyroidectomy. METHODS: The new technique encompasses the use of 3 styles of retractor: the suture retractor, the button retractor, and the adjustable button retractor. These retractors are all easy to make and are all useful in different situations. CONCLUSIONS: The new technique is a safe and cost-effective method. It reduces the operation time required to obtain good exposure without transecting the strap muscles. In addition, it is minimally invasive and confers cosmetic benefits.

Comprehensive analysis to identify DLEU2L/TAOK1 axis as a prognostic biomarker in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the deadliest malignant tumors that are harmful to human health. Increasing evidence has underscored the critical role of the competitive endogenous RNA (ceRNA) regulatory networks among various human cancers. However, the complexity and behavior characteristics of the ceRNA network in HCC were still unclear. In this study, we aimed to clarify a phosphatase and tensin homolog (PTEN)-related ceRNA regulatory network and identify potential prognostic markers associated with HCC. The expression profiles of three RNAs (long non-coding RNAs [lncRNAs], microRNAs [miRNAs], and mRNAs) were extracted from The Cancer Genome Atlas (TCGA) database. The DLEU2L-hsa-miR-100-5p/ hsa-miR-99a-5p-TAOK1 ceRNA network related to the prognosis of HCC was obtained by performing bioinformatics analysis. Importantly, we identified the DLEU2L/TAOK1 axis in the ceRNA by using correlation analysis, and it appeared to become a clinical prognostic model by Cox regression analysis. Furthermore, methylation analyses suggested that the abnormal upregulation of the DLEU2L/TAOK1 axis likely resulted from hypomethylation, and immune infiltration analysis showed that the DLEU2L/TAOK1 axis may have an impact on the changes in the tumor immune microenvironment and the development of HCC. In summary, the current study constructing a ceRNA-based DLEU2L/TAOK1 axis might be a novel important prognostic factor associated with the diagnosis and prognosis of HCC.

The minimally invasive effect of breast approach endoscopic thyroidectomy: an expert's experience.

We evaluated the invasiveness of breast approach endoscopic thyroidectomy (BAET) carried out by surgeon very experienced in this procedure. Twenty-four patients who underwent BAET and 19 patients who underwent conventional thyroidectomy were the study population. Postoperative pain was assessed by a visual analog scale (VAS). The values 2, 12, and 24 h after surgery were significantly lower in the BAET group than those in the conventional group. Serum IL-6 and CRP levels were measured by an ELISA preoperatively and at 2, 12, 24 and 48 h after operation. Their values increased significantly after both procedures when compared to preoperative levels with significant differences between the two groups detected at the 24-hour and 48-hour time points. Subjective and objective evidence supported the notion that BAET could become a minimally invasive procedure if the surgeon gained sufficient experience.

Prevalence, risk factors, and management of seroma formation after breast approach endoscopic thyroidectomy.

BACKGROUND: Breast approach endoscopic thyroidectomy (BAET) allows surgeons to remove a thyroid tumor from a remote site while providing a scarless cosmetic appearance in the neck. However, seroma formation after subcutaneous dissection could lead to flap detachment, incision dehiscence, and wound infection. Chronic formation of seromas could substantially compromise the esthetic outcome of BAET. We evaluated the prevalence, risk factors, and treatments of seroma after BAET. METHODS: A total of 344 patients who underwent BAET between 2001 and 2008 at our institution were recruited; data were collected prospectively. The characteristics and outcomes of patients who developed seromas were compared with those of patients who did not. Regression analysis was used to identify the independent risk factors for seroma formation. The frequency and volume of aspirations were noted until the seroma went into remission. RESULTS: The overall postoperative prevalence of seroma formation was 2.9%. There was a significant difference in seroma formation based on age, hypertension, body mass index (BMI), and area of subcutaneous dissection space (ASDS). Percutaneous aspiration alone or combined with external compression was extremely effective. The frequency and total volume of aspirations were 1-7 and 6-120 ml, respectively. As a result of prolonged seroma formation, one patient developed an expanding pseudo-bursa that created a tumor-like effect in the anterior chest wall. CONCLUSIONS: Seroma formation was an uncommon minor complication after BAET. Four independent etiologic factors could predispose patients to postoperative seroma formation. Percutaneous aspiration appeared to be very effective. Prolonged seroma formation followed by development of a pseudo-bursa could be very problematic and could substantially impair the esthetic effect of BAET.

The learning curve for endoscopic thyroidectomy: a single surgeon's experience.

BACKGROUND: Endoscopic thyroidectomy has been known to surgeons for only 20 years. Related studies still are needed to make up for the deficiency of clinical experience. Research on the learning curve for the endoscopic thyroidectomy could be the method for investigating the operation experience. METHODS: This retrospective study investigated 300 consecutive patients who underwent endoscopic thyroidectomy by a single endoscopist during the past 7 years. The study population was equally divided into 10 groups chronologically. Pearson's chi-square test and one-way analysis of variance were used to compare differences in the demographic data, operative time, operation score system, and follow-up data. RESULTS: The mean operative time was 98.07 min. The mean operation score was 6.00, and the rate of conversion to open surgery was 3.7%. There were no differences in demographic data or complications among the 10 groups. Subcutaneous edema occurred in five cases and transient recurrent laryngeal nerve palsy in five cases. There were significant differences in the mean operative time (p < 0.01) and the mean operation score (p < 0.01) among the 10 groups. Comparison of two neighboring groups showed differences in both operative time (p < 0.05) and operation score (p < 0.01) between groups 2 and 3 and in operation score between groups 5 and 6 (p < 0.05). CONCLUSIONS: The first 60 cases constitute the early stage of the learning curve for endoscopic thyroidectomy. The proficiency and stability of the operation reach the advanced level after 150 cases.

[Study on the operation score system for endoscopic thyroidectomy].

OBJECTIVE: To investigate the clinical significance of the operation score system for endoscopic thyroidectomy. METHODS: An operation score system based on 6 important procedure skills of endoscopic thyroidectomy was established. And a retrospective study of the first 300 consecutive patients underwent endoscopic thyroidectomy from July 2001 to December 2007 by a single surgeon was performed. The patients was divided into 10 consecutive groups chronologically, each comprising 30 cases. RESULTS: The mean operation score of all the patients was 6.0 and the mean operation time was 98.1 min. There were significant differences in the mean operation score, every skill score and the mean operation time among the 10 groups. In the consecutive two groups comparison, significant differences in the operation scores were observed between group 2 and 3 (P < 0.05) and between group 5 and 6 (P < 0.05). CONCLUSION: The operation score system for endoscopy thyroidectomy is a useful method to judge the proficiency and the stability of the operation.

Occurrence mechanism and coping paths of accidents of highly aggregated tourist crowds based on system dynamics.

The safety of highly aggregated tourist crowds is a challenging and important issue. This paper not only provided a comprehensive analysis of the accidents of highly aggregated tourist crowds but also determined the occurrence mechanism and coping paths. Based on the analysis of multiple cases, we found that the variable status of highly aggregated tourist crowds was the result of the interaction of three main elements: multisource pressure, state mutations and management responses. A series of factors interact and result in accidents, and the lack of a management response or a low-quality management response is the root cause of such accidents. A high-quality management response is a basic safety precaution for highly aggregated tourist crowds. Therefore, forming a virtuous circle of multisource pressure, state mutations and management responses is an effective path for coping with accidents.

[Influence of ENSO Events on the Hydrogen (δ2H) and Oxygen (δ18O) Isotopic Values of Precipitation in Shanghai].

An analysis of the effect of ENSO events with different strengths on the isotopic composition of precipitation is conducted based on test data for 206 precipitation samples collected from January 2012 to February 2017 in Shanghai coupled with the archives for Nanjing, Wuhan, Fuzhou, and Hong Kong from 1961 to 2012 from the Global Network of Isotopes in Precipitation (GNIP) database. During the research periods, the δD and δ18O values in precipitation are lower in summer and autumn but higher in winter and spring. The slope and intercept of the atmospheric precipitation lines during El Niño events are larger than during other times, while anti-temperature, precipitation amount, and vapor pressure effects are more significant than during La Niña events. The δ18O and deuterium excess values (value of d) of rainfall in Shanghai during El Niño and La Niña events of varied strengths have an obvious negative correlation with the oceanic Niño index (ONI), sea surface temperature anomaly (SSTA), and the extreme and cumulative values of ONI. Moreover, ENSO events are closely intertwined with the correlation between δ18O isotopic value in precipitation, ONI, and SSTA.

[Characteristics of Stable Isotope in Precipitation and Its Relationship with ENSO in Shanghai].

A total of 70 precipitation samples were collected from August 2014 to August 2015 in Shanghai and the oxygen and hydrogen isotope of precipitation were analyzed. The relationship between the δ18O and deuterium excess of precipitation and ENSO events was addressed. The results showed that δD and δ18O of precipitation in Shanghai were higher in winter and spring than in summer and fall. The slope of meteoric water line with these data was a little smaller than the global meteoric water line. The main reason could be the unbalanced secondary evaporation in the process of precipitation. The correlation between the δ18O in precipitation and temperature and precipitation varied in different time scales. On a seasonal scale, this work revealed that there was no significant temperature effect in winter, but significant precipitation effect was found in the annual scales, which was obviously affected by the atmospheric circulation. δ18O values and deuterium excess in precipitation recorded the La Niña and El Niño conversion process. During the La Niña event, the δ18O and d values were more negative than those in the El Niño event.

[Magnetic Response of Dust-loaded Leaves in Parks of Shanghai to Atmospheric Heavy Metal Pollution].

To reveal the magnetic response to the atmospheric heavy metal pollution in leaves along urban parks, Camphor leaf samples, widely distributed at urban parks, were collected along the year leading wind direction of Shanghai, by setting two vertical and horizontal sections, using rock magnetic properties and heavy metal contents analysis. The results showed that the magnetic minerals of samples were predominated by ferromagnetic minerals, and both the concentration and grain size of magnetite particles gradually decreased with the winter monsoon direction from the main industrial district. A rigorous cleaning of leaves using ultrasonic agitator washer could remove about 63%-90% of low-field susceptibility values of the leaves, and this strongly indicated that the intensity of magnetic signal was mainly controlled by the PMs accumulated on the leaves surfaces. Moreover, there was a significant linear relationship between heavy metals contents (Fe, Mn, Zn, Cu, Cr, V and Pb) and magnetic parameters (0.442 ≤ R ≤ 0.799, P < 0.05), which suggested that magnetic parameters of urban park leaves could be used as a proxy for atmospheric heavy metal pollution. The results of multivariate statistical analysis showed that the content of magnetic minerals and heavy metal indust-loaded tree leaves was affected by associated pollution of industry and traffic.

[Geochemical characteristics and sources of atmospheric particulates in Shanghai during dust storm event].

Atmospheric particulates were sampled from three sampling sites of Putuo, Minhang and Qingpu Districts in Shanghai between Oct. , 2009 and Oct. , 2010. In addition, particulate samples were also collected from Nantong, Zhengzhou, Xi'an, and Beijing city where dust storm dust transported along during spring. Element compositions of atmospheric particulates were determined by XRF and ICP-MS. The concentrations of major and trace elements in atmospheric particulates from Putuo, Minhang and Qingpu Districts were similar, indicating their common source. The UCC standardization distribution map showed that the major element composition of dust storm samples was similar to that of loess in northwestern China, indicating that the dust storm dust was mainly derived from Western desert and partly from local area. The REE partition patterns of dust storm dusts among different cities along dust transport route were similar to each other, as well as to those of northern loess, which indicates that the dust storm samples may have the same material source as loess, which mainly comes from crust material. However, the REE partition patterns of non-dust storm particulates were different among the studied cities, and different from those of loess, which suggests that the non-dust storm samples may be mixed with non-crust source material, which is different from dust storm dust and loess. The major element composition and REE partition pattern are effective indicators for source tracing of dust storm dust.

Dual-sided composite mesh repair of hiatal hernia: our experience and a review of the Chinese literature.

AIM: To summarize our experience in the application of Crurasoft® for antireflux surgery and hiatal hernia (HH) repair and to introduce the work of Chinese doctors on this topic. METHODS: Twenty-one patients underwent HH repair with Crurasoft® reinforcement. Gastroesophageal reflux disease (GERD) and HH-related symptoms including heartburn, regurgitation, chest pain, dysphagia, and abdominal pain were evaluated preoperatively and 6 mo postoperatively. A patient survey was conducted by phone by one of the authors. Patients were asked about "recurrent reflux or heartburn" and "dysphagia". An internet-based Chinese literature search in this field was also performed. Data extracted from each study included: number of patients treated, hernia size, hiatorrhaphy, antireflux surgery, follow-up period, recurrence rate, and complications (especially dysphagia). RESULTS: There were 8 type I, 10 type II and 3 type III HHs in this group. Mean operative time was 119.29 min (range 80-175 min). Intraoperatively, length and width of the hiatal orifice were measured, (4.33 ± 0.84 and 2.85 ± 0.85 cm, respectively). Thirteen and eight Nissen and Toupet fundoplications were performed, respectively. The intraoperative complication rate was 9.52%. Despite dysphagia, GERD-related symptoms improved significantly compared with those before surgery. The recurrence rate was 0% during the 6-mo follow-up period, and long-term follow-up disclosed a recurrence rate of 4.76% with a mean period of 16.28 mo. Eight patients developed new-onset dysphagia. The Chinese literature review identified 12 papers with 213 patients. The overall recurrence rate was 1.88%. There was no esophageal erosion and the rate of dysphagia ranged from 0% to 24%. CONCLUSION: The use of Crurasoft® mesh for HH repair results in satisfactory symptom control with a low recurrence rate. Postoperative dysphagia continues to be an issue, and requires more research to reduce its incidence.

[Establishment of sleeve gastrectomy model in diet-induced obese Sprague-Dawley rats].

OBJECTIVE: To establish sleeve gastrectomy(SG) rats model of obese type 2 diabetes mellitus(T2DM) for the research of hypoglycemic mechanism. METHODS: Nine male Sprague-Dawley (6-week-old) rats were fed with high-sucrose and high-fat diet for 4 weeks, developing diet-induced obesity (DIO) rats model. The rats were then randomly divided into two groups. Six rats of them underwent sleeve gastrectomy(SG) as the sleeve gastrectomy group[SGG, body weight (471.8±17.9) g] and the other three rats underwent a laparotomy and stomach manipulation as the sham operative group[SOG, body weight (467.0±8.4) g]. The body weight, caloric intake and peripheral blood concentration of total ghrelin of rats were recorded after operation. RESULTS: The weight of all the rats declined progressively after operation. The weight of the rats in SOG began to rise on the 5th postoperative day(POD) and regain their preoperative levels on the average 22nd POD. However, the weight of the rats in SGG began to rise slowly from the 9th POD, but was still lower than that of SOG[(487.4±10.1) g] and preoperative levels[(471.8±17.9) g] on the 28th POD[(420.1±18.6) g](P=0.001). Average caloric intake of rats in SGG was significantly lower than that of SOG after operation, but there was no significant difference between the two groups(P=0.121). The ghrelin level of SGG showed a continuous decreasing trend after intervention, decreased by 17.4% compared with the preoperative level (1595.1±14.4 ng/L) on the 28th POD[(1316.8±14.8) ng/L]. The ghrelin level of SOG did not change obviously before and after operation and both groups differ statistically(P=0.000). CONCLUSIONS: A SG rat model is successfully established. This model can be used for the further study of mechanism analysis of T2DM resolution after surgery.

Routine central neck dissection in differentiated thyroid carcinoma: a systematic review and meta-analysis.

OBJECTIVE/HYPOTHESIS: The role of central neck dissection (CND) remains controversial in differentiated thyroid cancer (DTC). STUDY DESIGN: Systematic review and meta-analysis. METHODS: A systematic review and meta-analysis focusing on surgical morbidities and locoregional recurrence after total thyroidectomy (TT) with CND versus TT alone was performed. RESULTS: Sixteen trials were analyzed. There was no increased risk of recurrent laryngeal nerve (RLN) injury (temporary or permanent), permanent hypocalcemia, or locoregional recurrence when CND was performed in addition to TT. Postoperative temporary hypocalcemia was more common after TT with CND than after TT alone. CONCLUSIONS: TT alone results in less surgical morbidity in the immediate postoperative period and an identical locoregional recurrence rate compared with TT plus CND.

Current status of endoscopic thyroid surgery in China.

The first cases of video-assisted thyroidectomy and scarless endoscopic thyroidectomy were reported in China in 2001 and 2002, respectively. Breast approach endoscopic thyroidectomy (BAET) has become the most popular procedure for treating thyroid disease in China. Chinese doctors did not pioneer this approach, but contributed toward improvement in technical details such as incision selection, creation of a working space, suture exposure, and control of intraoperative bleeding. Relatively large series confirmed that BAET is a safe procedure but has a long learning curve that can be overcome with training. Surgical stress was not significantly increased despite the larger subcutaneous dissection. BAET to treat malignancy is feasible, but larger series and longer follow-up are warranted before its widespread acceptance.

Evidence-based appraisal in laparoscopic Nissen and Toupet fundoplications for gastroesophageal reflux disease.

AIM: To demonstrate the optimal surgical procedure for gastroesophageal reflux disease. METHODS: The electronic databases of Medline, Elsevier, Springerlink and Embase over the last 16 years were searched. All clinical trials involved in the outcomes of laparoscopic Nissen fundoplication (LNF) and laparoscopic Toupet fundoplication (LTF) were identified. The data of assessment in benefits and adverse results of LNF and LTF were extracted and compared using meta-analysis. RESULTS: We ultimately identified a total of 32 references reporting nine randomized controlled trials, eight prospective cohort trials and 15 retrospective trials. These studies reported a total of 6236 patients, of whom 4252 (68.18%) underwent LNF and 1984 (31.82%) underwent LTF. There were no differences between LNF and LTF in patients' satisfaction, perioperative complications, postoperative heartburn, reflux recurrence and re-operation. Both LNF and LTF enhanced the function of lower esophageal sphincter and improved esophagitis. The postoperative dysphagia, gas-bloating syndrome, inability to belch and the need for dilatation after LNF were more common than after LTF. Subgroup analyses showed that dysphagia after LNF and LTF was similar in patients with normal esophageal peristalsis (EP), but occurred more frequently in patients with weak EP after LNF than after LTF. Furthermore, patients with normal EP after LNF still had a higher risk of developing dysphagia than did patients with abnormal EP after LTF. CONCLUSION: Compared with LNF, LTF offers equivalent symptom relief and reduces adverse results.

[Geochemical character of precipitation in summer of Shanghai 2008-2009].

The chemical compositions of the rainwater collected in Shanghai in Summer of 2008-2009 were investigated. The chemical character and pollutant source of rainwater were evaluated depended on HYSPLIT model, ions tracer techniques, correlation and principal component analysis. The results showed that: (1) the mean pH in rain was 4.72 and 4.68; (2) the frequency of acid rain was 53.30% and 63.30%, respectively, in 2008 and 2009; (3) ionic concentration was SO4(2-) > NH4+ > NO3- > Cl- > Ca2+ > Na+ > Mg2+ > K+, in which the secondary components like SO4(2-), NO3- and NH4+ contributed significantly to total ions of rainwater and they accounted for 55.01% and 65.97% of total ions in 2008 and 2009, respectively, which indicate the severe secondary pollution in Shanghai; (4) the ratio of SO4(2-) to NO3- in Summer precipitation in 2008 and 2009 was 3.19 and 2.13, respectively, which implies sulfuric-nitrous mixed type of precipitation; (5) the content of DOC varied from 1.36 mg/L to 10.69 mg/L and average value was 2.44 mg/L in rainwater; (6) SO4(2-) and NO3- were mainly in the form of (NH4) 2SO4 and NH4NO3, which showed the dominant neutralization effect of NH4+ over Ca2+ in Summer. Source identification indicated that SO4(2-), NH4+, NO3-, K+ and most Ca2+ derived from anthropogenic sources, while Mg2+ and Cl- derived from both marine and non-marine but non-marine was over marine. The chemistry of precipitation in Shanghai was impacted by local pollutants and the long-and moderate-range transport by Southwest monsoon according to backward trajectory analysis.