The comparison of an accessible C-shaped partial stapled hemorrhoidopexy (C-PSH) versus circular stapled hemorrhoidopexy (CSH) in patients with grade IV hemorrhoids: a retrospective cohort study.

OBJECTIVES: The objectives of this study were to present an accessible C-shaped partial stapled hemorrhoidopexy (C-PSH) in the treatment of grade IV hemorrhoids and to assess long-term outcomes of this technique compared with circular stapled hemorrhoidopexy (CSH). METHODS: Conventional CSH kits combined with an intestinal spatula were used for performing C-PSH. A total of 256 patients with grade IV hemorrhoids referred to Hangzhou Third People's Hospital between January 2016 and June 2017 were obtained: 122 (47.7%) with C-PSH, and 134 (52.3%) with CSH. After propensity score matching, 222 patients (111 in C-PSH group and 111 in CSH group) were ultimately analyzed. The primary outcome was the five-year recurrence rate of hemorrhoids. Secondary outcomes included intraoperative outcomes, postoperative outcomes and complications. RESULTS: The operative time in the C-PSH group was slightly longer than that in the CSH group (p < 0.01). The vertical length of rectal mucosa specimen in the C-PSH group was shorter than that in the CSH group (p < 0.01). Compared with the CSH group, fecal urgency incidence and numeric rating scale (NRS) score at first defecation were lower in the C-PSH group (p < 0.05). Major complication rate in the CSH group was higher than that in the C-PSH group (p = 0.03). Five-year recurrence rate between the C-PSH group and CSH group was comparable (p > 0.05). Multivariate Cox regression analysis revealed that constipation was an independent prognostic factor for hemorrhoidal recurrence. CONCLUSIONS: The accessible C-PSH seems to be a safe and effective technique in managing grade IV hemorrhoids. It has advantages in alleviating postoperative pain at first defecation, fecal urgency and major complications compared with CSH. It could be an alternative technique in the treatment of grade IV hemorrhoids.

Liver Metabolomics Analysis Revealing Key Metabolites Associated with Different Stages of Nonalcoholic Fatty Liver Disease in Hamsters.

BACKGROUND AND AIM: Nonalcoholic fatty liver disease (NAFLD) is not only the top cause of liver diseases but also a hepatic-correlated metabolic syndrome. This study performed untargeted metabolomics analysis of NAFLD hamsters to identify the key metabolites to discriminate different stages of NAFLD. METHODS: Hamsters were fed a high-fat diet (HFD) to establish the NAFLD model with different stages (six weeks named as the NAFLD1 group and twelve weeks as the NAFLD2 group, respectively). Those liver samples were analyzed by untargeted metabolomics (UM) analysis to investigate metabolic changes and metabolites to discriminate different stages of NAFLD. RESULTS: The significant liver weight gain in NAFLD hamsters was observed, accompanied by significantly increased levels of serum triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), alanine aminotransferase (ALT), and aspartate aminotransferase (AST). Moreover, the levels of TG, LDL-C, ALT, and AST were significantly higher in the NAFLD2 group than in the NAFLD1 group. The UM analysis also revealed the metabolic changes; 27 differently expressed metabolites were detected between the NAFLD2 and NAFLD1 groups. More importantly, the levels of N-methylalanine, allantoin, glucose, and glutamylvaline were found to be significantly different between any two groups (control, NAFLD2 and NAFLD1). Receiver operating characteristic curve (ROC) curve results also showed that these four metabolites are able to distinguish control, NAFLD1 and NAFLD2 groups. CONCLUSION: This study indicated that the process of NAFLD in hamsters is accompanied by different metabolite changes, and these key differently expressed metabolites may be valuable diagnostic biomarkers and responses to therapeutic interventions.

New Insights on the Size-Dependent Inhibition of Enzymes by Gold Nanoparticles.

Particle size might affect the inhibition behaviors of gold nanoparticles (AuNPs) on enzyme activity by influencing the density of binding sites (ρ), the association constant (Ka), the steric hindrance of enzymes by AuNPs, the binding orientations of the enzyme on AuNPs, as well as the structural changes of enzymes. In previous studies, the effects of the above-mentioned factors, which could not be ignored in the applications of enzymatic electrochemistry, were often overshadowed by the effects of surface area. In order to study the size effect on the inhibition types and inhibitory ability of enzymes by AuNPs, we investigated the inhibition behaviors of chymotrypsin (ChT) by AuNPs with three different sizes (D1-AuNCs, D3-AuNPs, and D6-AuNPs) under the same surface area concentration. The results showed that both of the inhibition types and the inhibition ability varied with the particle size of AuNPs. D1-AuNCs inhibited ChT noncompetitively, while D3/D6-AuNPs inhibited ChT competitively. Contrary to the common sense, D6-AuNPs showed a weaker inhibitory ability than D3-AuNPs. By means of zeta potential, agarose gel electrophoresis, isothermal titration calorimetry, synchronous fluorescence spectroscopy, and circular dichroism, the mechanism of the weak inhibitory ability of D6-AuNPs was found to be the standing binding orientation caused by the small curvature. This work had certain guiding significance for the biosafety of AuNPs, the development of nanoinhibitors, as well as the applications of AuNPs in enzymatic electrochemistry.

GhbZIP30-GhCCCH17 module accelerates corm dormancy release by reducing endogenous ABA under cold storage in Gladiolus.

Gladiolus hybridus is one of the most popular flowers worldwide. However, its corm dormancy characteristic largely limits its off-season production. Long-term cold treatment (LT), which increases sugar content and reduces abscisic acid (ABA), is an efficient approach to accelerate corm dormancy release (CDR). Here, we identified a GhbZIP30-GhCCCH17 module that mediates the antagonism between sugars and ABA during CDR. We showed that sugars promoted CDR by reducing ABA levels in Gladiolus. Our data demonstrated that GhbZIP30 transcription factor directly binds the GhCCCH17 zinc finger promoter and activates its transcription, confirmed by yeast one-hybrid, dual-luciferase (Dual-LUC), chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR) and electrophoretic mobility shift assay (EMSA). GhCCCH17 is a transcriptional activator, and its nuclear localisation is altered by surcose and cytokinin treatments. Both GhbZIP30 and GhCCCH17 positively respond to LT, sugars, and cytokinin treatments. Silencing GhbZIP30 or GhCCCH17 resulted in delayed CDR by regulating ABA metabolic genes, while their overexpression promoted CDR. Taken together, we propose that the GhbZIP30-GhCCCH17 module is involved in cold- and glucose-induced CDR by regulating ABA metabolic genes.

Metagenomic analysis reveals specific BTEX degrading microorganisms of a bacterial consortium.

Petroleum hydrocarbon contamination is of environmental and public health concerns due to its toxic components. Bioremediation utilizes microbial organisms to metabolism and remove these contaminants. The aim of this study was to enrich a microbial community and examine its potential to degrade petroleum hydrocarbon. Through successive enrichment, we obtained a bacterial consortium using crude oil as sole carbon source. The 16 S rRNA gene analysis illustrated the structural characteristics of this community. Metagenomic analysis revealed the specific microbial organisms involved in the degradation of cyclohexane and all the six BTEX components, with a demonstration of the versatile metabolic pathways involved in these reactions. Results showed that our consortium contained the full range of CDSs that could potentially degrade cyclohexane, benzene, toluene, and (o-, m-, p-) xylene completely. Interestingly, a single taxon that possessed all the genes involved in either the activation or the central intermediates degrading pathway was not detected, except for the Novosphingobium which contained all the genes involved in the upper degradation pathway of benzene, indicating the synergistic interactions between different bacterial genera during the hydrocarbon degradation.

LncRNA UCA1 Participates in De Novo Synthesis of Guanine Nucleotides in Bladder Cancer by Recruiting TWIST1 to Increase IMPDH1/2.

Metabolic dysregulation has been identified as one of the hallmarks of cancer biology. Based on metabolic heterogeneity between bladder cancer tissues and adjacent tissues, we discovered several potential driving factors for the bladder cancer occurrence and development. Metabolic genomics showed purine metabolism pathway was mainly accumulated in bladder cancer. Long noncoding RNA urothelial carcinoma-associated 1 (LncRNA UCA1) is a potential tumor biomarker for bladder cancer diagnosis and prognosis, and it increases bladder cancer cell proliferation, migration, and invasion via the glycolysis pathway. However, whether UCA1 plays a role in purine metabolism in bladder cancer is unknown. Our findings showed that UCA1 could increase the transcription activity of guanine nucleotide de novo synthesis rate limiting enzyme inosine monophosphate dehydrogenase 1 (IMPDH1) and inosine monophosphate dehydrogenase 2 (IMPDH2), triggering in guanine nucleotide metabolic reprogramming. This process was achieved by UCA1 recruiting the transcription factor TWIST1 which binds to the IMPDH1and IMPDH2 promoter region. Increased guanine nucleotide synthesis pathway products stimulate RNA polymerase-dependent production of pre-ribosomal RNA and GTPase activity in bladder cancer cells, hence increasing bladder cancer cell proliferation, migration, and invasion. We have demonstrated that UCA1 regulates IMPDH1/2-mediated guanine nucleotide production via TWIST1, providing additional evidence of metabolic reprogramming.

Preoperative neoadjuvant chemotherapy in patients with breast cancer evaluated using strain ultrasonic elastography.

BACKGROUND: The incidence of breast cancer in China is increasing while its mortality rate is decreasing. The annual breast cancer incidence in China is 39.2 million, accounting for two-thirds of the urban population. In China, breast cancer is the fifth most common malignant tumor overall and the most common in women, accounting for 17% of female malignant tumors. AIM: To investigate the accuracy of strain ultrasound elastography (SUE) on the evaluation of preoperative neoadjuvant chemotherapy (NAC) in breast cancer. METHODS: Overall, 90 patients with breast cancer treated at our hospital between January 2018 and February 2019 were selected for this study. The patients received six cycles of NAC with docetaxel, epirubicin, and cyclophosphamide. Surgical treatment was also performed, and pathological reactivity was assessed. The patients were evaluated using conventional ultrasonography and SUE before biopsy. The differences between groups were analyzed to calculate the mean and standard deviation with significance measured using a t-test, while multivariate analysis was performed using logistic regression analysis. RESULTS: Of the patients analyzed, 20 had a pathological complete remission (pCR) while 70 did not achieve pCR after NAC. The ratio of the elastic strain ratio (SR) and elastic score of 4-5 in patients with pCR were 5.5 ± 1.16 and 15.00%, respectively; these were significantly lower than those in patients without pCR (85%) and significantly higher than in patients without pCR (14%). SR and elastic score 4-5 were independent factors influencing NAC efficacy (OR=0.644, 1.426 and 1.366, respectively, P < 0.05). SR was positively correlated with elasticity score (rs = 0.411, P < 0.05). The area under the receiver operator characteristic curve of SR and SR combined with elastic score in predicting patients without pCR was 0.822 and 0.891, respectively (P < 0.05). CONCLUSION: Strain ultrasonic elastography may be used to evaluate the effects of preoperative NAC in patients with breast cancer.

Predicting the Risk of Acute Kidney Injury in Patients After Percutaneous Coronary Intervention (PCI) or Cardiopulmonary Bypass (CPB) Surgery: Development and Assessment of a Nomogram Prediction Model.

BACKGROUND We sought to create a model that incorporated ultrasound examinations to predict the risk of acute kidney injury (AKI) after percutaneous coronary intervention (PCI) or cardiopulmonary bypass (CPB) surgery. MATERIAL AND METHODS A total of 292 patients with AKI after PCI or CPB surgery were enrolled for the study. Afterwards, treatment-related information, including data pertaining to ultrasound examination, was collected. A random forest model and multivariate logistic regression analysis were then used to establish a predictive model for the risk of AKI. Finally, the predictive quality and clinical utility of the model were assessed using calibration plots, receiver-operating characteristic curve, C-index, and decision curve analysis. RESULTS Predictive factors were screened and the model was established with a C-index of 0.955 in the overall sample set. Additionally, an area under the curve of 0.967 was obtained in the training group. Moreover, decision curve analysis also revealed that the prediction model had good clinical applicability. CONCLUSIONS The prediction model was efficient in predicting the risk of AKI by incorporating ultrasound examinations and a number of factors. Such included operation methods, age, congestive heart failure, body mass index, heart rate, white blood cell count, platelet count, hemoglobin, uric acid, and peak intensity (kidney cortex as well as kidney medulla).

Demoralization and depression in Chinese cancer patients.

OBJECTIVE: Demoralization and depression are common in cancer patients and closely related to suicide. But the association and difference between them are not clear. The aim of this study is to investigate demoralization and depression in Chinese cancer patients. METHODS: This study is a cross-sectional study. Two hundred ninety-six cancer patients completed the questionnaire. First is using the DS-II to evaluate demoralization in advanced cancer patients and using the PHQ-9 to evaluate their depression. Then determine the association between demoralization and depression by Pearson rank correlation test. Finally, an ANOVA was conducted using DS-II as the categorical variable and PHQ-9 as the continuous variable and using PHQ-9 as the categorical variable and DS-II as the continuous variable. RESULTS: There is a positive association between demoralization and depression. A special case that patients with high demoralization but low depression was discovered, which accounted for a large proportion. CONCLUSION: Demoralization and depression are two different psychological states, which require medical staff to identify and take corresponding intervention measures in time. Patients with high demoralization but low depression require further attention.

Evolution of As speciation with depth in a soil profile with a geothermal As origin.

High contents of arsenic were detected in soils in Guandu plain, northwest Taiwan. To determine the sources and speciation of As in the soils, the depth profiles of soil properties, elemental composition and As speciation were investigated. The As concentrations in the soil profile ranged from 152 to 1222 mg kg-1, with the highest concentration at the depth of 70-80 cm. The As distribution was found to be positively correlated to Fe, Pb, and Ba. The As(V)-adsorbed ferrihydrite and scorodite were the predominant phases in the top layers (<50 cm), while beudantite was the predominant phase below 50 cm along with As(III)- and As(V)-adsorbed ferrihydrite as the minor components. The results of sequential extraction showed that As-associated with noncrystalline and crystalline Fe/Al hydrous oxides and residual phases were predominant at the depths of 0-60, 60-100 and 100-140 cm, respectively, indicating an increasing As recalcitrance with soil depth. Based on the soil properties, and elemental and mineral compositions at different soil depths, the origin of beudantite in the soils was likely allogenic rather than authigenic or anthropogenic. The formation of scorodite in the surface soils was suggested to be transformed from beudantite. As-associated Fe hydrous oxides may be contributed by the progressive dissolution of beudantite and scorodite, and the continuous influxes of As and Fe. While Fe hydrous oxides were able to immobilize As during the dissolution of As-bearing minerals, the increase of As mobility in soils may imply an increase in the environmental risk of As over time.

Effects of long-term paddy rice cultivation on soil arsenic speciation.

Geochemical behavior of arsenic (As) in rice paddy soils determines the availability and mobility of As in the soils, but little is known about the long-term effects of paddy rice cultivation on As speciation in the soils. In this study, surface soil samples were collected from a rice paddy land and its adjacent dry land with similar soil properties and known cultivation histories. The soils of the paddy land and dry land contained 378 and 423 mg As kg-1, respectively. The predominant As species in the soils were investigated using As K-edge X-ray absorption spectroscopy (XAS) in combination with two sequential chemical fractionation methods. The XAS results showed that the predominant As species in the soils were As(III)- and As(V)-ferrihydrite, As(V)-goethite and scorodite. In comparison to the dry land soil, the paddy land soil contained a higher proportion of As(V)-ferrihydrite and a lower proportion of scorodite. The results of chemical fractionation revealed that As in the paddy land soil was more labile than that in the dry land soil. It is therefore suggested that long-term rice cultivation enhances the mobility and availability of As in paddy soils.

B-lines by lung ultrasound predict heart failure in hospitalized patients with acute anterior wall STEMI.

OBJECTIVE: B-line imaging by lung ultrasound (LUS) is a new tool for evaluating subclinical pulmonary congestion. The aim of this study was to explore the prognostic value of B-line number at admission in predicting symptomatic heart failure (HF) during hospitalization in acute anterior wall STEMI patients. METHODS: This was a prospective cohort study which consecutively enrolled 96 anterior wall STEMI patients without dyspnea at admission. Pulmonary auscultation, NT-proBNP test, LUS, and echocardiography were performed within 5 hours after primary PCI. Rale occurrence, plasma NT-proBNP levels, B-line number, LVEF, E/e' were recorded, and their predictive value for HF in-hospital was analyzed. RESULTS: A total of 19 patients developed symptomatic HF. Median B-line number, NT-proBNP levels, and E/e' in the HF group were higher than those of the nonheart-failure (NHF) group (P < 0.001) while LVEF was lower (P = 0.002). There was no statistical difference in rale occurrence between the two groups. Multivariate logistic regression demonstrated that B-lines, E/e', and NT-proBNP independently predicted HF during hospitalization. According to the area under the ROC curve, the strongest predictor is B-lines (0.972), followed by NT-proBNP (0.936) and E/e' (0.928), and combining the three indicators was better than any single parameter (P = 0.048). B-line cutoff ≥18 could well predict HF event with specificity and sensitivity of 94.7% and 94.8%, respectively. CONCLUSION: Subclinical pulmonary congestion reflected by B-lines can independently predict symptomatic HF during hospitalization in patients with anterior wall STEMI, LUS will act as a complementary tool for evaluating cardiac function.

Isotope dilution LC/ESI--MS-MS quantitation of urinary 1,4-bis(N-acetyl-S-cysteinyl)-2-butanone in mice and rats as the biomarker of 1-chloro-2-hydroxy-3-butene, an in vitro metabolite of 1,3-butadiene.

1-Chloro-2-hydroxy-3-butene (CHB) is a possible metabolite of 1,3-butadiene, a carcinogenic air pollutant. To demonstrate its formation in vivo, it is desirable to develop a practical biomarker and the corresponding analysis method. CHB can undergo alcohol dehydrogenase- and cytochromes P450 enzymes (P450)-mediated oxidation to yield 1-chloro-3-buten-2-one (CBO), which readily forms glutathione conjugates. We hypothesized that CBO-derived mercapturic acids, which are the expected biotransformed products of CBO-glutathione conjugates, could be used as CHB biomarkers. Thus, in the present study, we investigated the in vivo biotransformation of CHB into CBO-derived mercapturic acids. Because the reaction of CBO with N-acetyl-l-cysteine yields two products, 1,4-bis(N-acetyl-S-cysteinyl)-2-butanone (NC1) and 1-chloro-4-(N-acetyl-S-cysteinyl)-2-butanone (NC2), we first developed an isotope dilution LC/ESI--MS-MS method to quantitate urinary NC1 and NC2, and then determined their concentrations in urine of C57BL/6 mice and Sprague-Dawley rats administered CHB. Since no NC2 was detected in samples, the LC/ESI--MS-MS method was optimized specifically for NC1. NC1 was enriched through solid phase extraction with the recovery being 75-82%. The limits of detection and quantitation were 6.8 and 34 fmol/0.1 mL for mouse urine, and 4.5 and 7.1 fmol/0.1 mL for rat urine, respectively. In urine of animals before CHB administration, no NC1 was detected; in mice administered CHB at 10 and 30 mg/kg, and rats at 5 and 15 mg/kg, NC1 was detected and its concentrations in urine from animals given higher doses were 3-6 fold higher than those given lower doses. Moreover, the NC1 concentrations in urine during 0-8 h were 4-6 fold and 10-11 fold higher than those during 8-24 h for mice and rats, respectively. The results demonstrated that CHB could be in vivo biotransformed into NC1, which could be used as a practical CHB biomarker.

Correction: Targeting CDH17 Suppresses Tumor Progression in Gastric Cancer by Downregulating Wnt/ß-Catenin Signaling.

[This corrects the article DOI: 10.1371/journal.pone.0056959.].

Effects of fluorescent dissolved organic matters (FDOMs) on perfluoroalkyl acids (PFAAs) in lake and river water.

This study presents the effects of fluorescent dissolved organic matters (FDOM) on perfluoroalkyl acids (PFAAs) in western Lake Chaohu and its inflow rivers. The surface water samples from the 27 sites in western Lake Chaohu and its inflow rivers were collected in March and September 2013. The contents of PFAAs and the FDOM in the water samples were measured by a high-performance liquid chromatograph - mass spectrometer (HPLC-MS) and by a fluorescence spectrophotometer, respectively. The temporal-spatial distributions of PFAAs and FDOM, as well as their interrelationships, were investigated. Eleven PFAA components were detected, and the mean concentration of total PFAAs (TPFAAs) in western Lake Chaohu and its inflow rivers were 12.93 ±â€¯5.19 ng/L and 11.84 ±â€¯9.50 ng/L, respectively. PFOA was the predominant contaminant in two regions (7.13 ±â€¯3.07 ng/L and 4.30 ±â€¯2.14 ng/L) followed by PFHxA (1.72 ±â€¯0.80 ng/L and 1.42 ±â€¯1.41 ng/L) and PFBA (1.44 ±â€¯0.78 ng/L and 1.37 ±â€¯0.78 ng/L). The mean concentration of total FDOM in western Lake Chaohu and its inflow rivers were 220.0 ±â€¯40.30 µg quinine sulfate units (Q.S.)/L and 406.3 ±â€¯213.1 µg Q.S./L, respectively. The significant, positive correlations were observed between the PFAAs and FDOMs in both the lake area and the inflow rivers. However, no significant correlation was observed between PFAAs and the dissolved organic carbon (DOC) in the lake area. This finding indicated that the residues and distributions of PFAAs were significantly dependent on the compositions of dissolved organic matters (DOM) and not on the total content of DOM.

Effect of Qufengtongluo Decoction on PI3K/Akt Signaling Pathway in the Kidney of Type 2 Diabetes Mellitus Rat (GK Rat) with Diabetic Nephropathy.

Qufengtongluo (QFTL) decoction is an effective treatment for diabetic nephropathy (DN). However, the underlying molecular mechanism is still unclear. In this study, we try to investigate whether QFTL decoction acts via inhibiting PI3K/Akt signaling pathway. Twenty-four GK rats were randomly divided into 3 groups: blank group, sham-operated group, and QFTL group. After model establishment, rats in QFTL group were given QFTL decoction by gavage, while the rest were given pure water. During the 8-week intervention, 24 hr urinal protein was measured every 2-3 weeks. After intervention, kidneys were removed for pathological smear, quantitative real-time PCR, and western blotting to detect expression levels of p-PI3K, p-Akt, PTEN, TGF-ß, PI3K mRNA, Akt mRNA, PTEN mRNA, and TGF-ß mRNA. QFTL group showed a slighter degree of renal fibrosis in Masson and PASM staining and a greater reduction of 24 hr urinal protein than blank group. Compared to blank group, expression levels of p-PI3K, p-Akt, PI3K mRNA, and Akt mRNA were lower in QFTL group, while expression levels of PTEN and PTEN mRNA were higher. Besides, TGF-ß was downregulated by QFTL decoction. In conclusion, this study suggests that QFTL decoction might inhibit PI3K/Akt signaling pathway via activating PTEN and inhibiting TGF-ß.

Development and Validation of a Nomogram to Predict the Benefit of Adjuvant Radiotherapy for Patients with Resected Gastric Cancer.

Background: The US guidelines for gastric cancer (GC) recommend adjuvant radiotherapy (ART) combined with 5-fluorouracil as a standard treatment for patients with resected locally advanced GC. However, patient selection criteria for optimizing the use of adjuvant therapies are lacking. In this study, we developed and validated a nomogram to predict the individualized overall survival (OS) benefit of ART among patients with resected ≥stage IB GC. Patients and Methods: The 2002-2006 Surveillance, Epidemiology, and End Results (SEER) data of 5,206 patients with resected GC were used as a training set for the development of a nomogram. The 2007-2008 SEER data of 1,986 patients with resected GC were used as validation data. Results: In the multivariate analysis weighted by inverse propensity score, the efficacy of ART varied by the ratio of positive to examined nodes (Pinteraction <0.01). The magnitude of this difference was included in the nomogram with associated prognosticators to predict the 3- and 5-year OS with and without ART. The nomogram showed significant prognostic superiority to the 8th TNM staging in the training set (Concordance index, 0.68 versus 0.65; P<0.01) and the validation set (Concordance index, 0.68 versus 0.64; P<0.01). Moreover, the calibration was accurate, and the actual efficacy of ART was positively correlated with the nomogram-estimated survival benefit from ART (Pinteraction <0.01 and Pinteraction =0.02 in the training set and the validation set, respectively). Conclusion: The nomogram can aid individualized clinical decision making by estimating the 3- and 5-year OS and potential benefits of ART among patients with resected GC.

Molecular Snuggle and Stretch of a Tetraammonium Chain in the Construction of a Hetero-[4]pseudorotaxane with CyclopentanoQ[6] and Classical Q[7].

A hetero-[4]pseudorotaxane was designed to perform a molecular machine function of contraction and expansion utilizing the binding features of CyP6Q[6] and classical Q[7]. First, the effect on guest binding of equatorial substitution on Q[6]'s was examined by comparing Me4Q[6] and CyP6Q[6] against classical Q[6] using eight guest molecules varying in shape, size, neutrality, or cations. Second, the binding data provided optimal structural features for the design of a tetraammonium ion chain to effect the synthesis of the hetero-[4]pseudorotaxane. Finally, the hetero-[4]pseudorotaxane was constructed, and the order of component placement was examined for function and thermodynamic stability in relation to component order on the molecular axle.

Survey of basic medical researchers on the awareness of animal experimental designs and reporting standards in China.

OBJECTIVE: To investigate the awareness and use of the Systematic Review Center for Laboratory Animal Experimentation's (SYRCLE) risk-of-bias tool, the Animal Research: Reporting of In Vivo Experiments (ARRIVE) reporting guidelines, and Gold Standard Publication Checklist (GSPC) in China in basic medical researchers of animal experimental studies. METHODS: A national questionnaire-based survey targeting basic medical researchers was carried in China to investigate the basic information and awareness of SYRCLE's risk of bias tool, ARRIVE guidelines, GSPC, and animal experimental bias risk control factors. The EpiData3.1 software was used for data entry, and Microsoft Excel 2013 was used for statistical analysis in this study. The number of cases (n) and percentage (%) of classified information were statistically described, and the comparison between groups (i.e., current students vs. research staff) was performed using chi-square test. RESULTS: A total of 298 questionnaires were distributed, and 272 responses were received, which included 266 valid questionnaires (from 118 current students and 148 research staff). Among the 266 survey participants, only 15.8% was aware of the SYRCLE's risk of bias tool, with significant difference between the two groups (P = 0.003), and the awareness rates of ARRIVE guidelines and GSPC were only 9.4% and 9.0%, respectively; 58.6% survey participants believed that the reports of animal experimental studies in Chinese literature were inadequate, with significant difference between the two groups (P = 0.004). In addition, only approximately 1/3 of the survey participants had read systematic reviews and meta-analysis reports of animal experimental studies; only 16/266 (6.0%) had carried out/participated in and 11/266 (4.1%) had published systematic reviews/meta-analysis of animal experimental studies. CONCLUSIONS: The awareness and use rates of SYRCLE's risk-of-bias tool, the ARRIVE guidelines, and the GSPC were low among Chinese basic medical researchers. Therefore, specific measures are necessary to promote and popularize these standards and specifications and to introduce these standards into guidelines of Chinese domestic journals as soon as possible to raise awareness and increase use rates of researchers and journal editors, thereby improving the quality of animal experimental methods and reports.

[Assessment of PM2.5 Pollution Mitigation due to Emission Reduction from Main Emission Sources in the Bejing-Tianjin-Hebei Region].

This study chose two months (January and July) in 2012 which represent winter and summer respectively, to assess the effects of fine particle(PM2.5) pollution elimination due to emission control from different sectors in the Bejing-Tianjin-Hebei region by using CMAQ/2D-VBS modeling system. The results showed that, industrial emissions contributed most to PM2.5 pollution in the Beijing-Tianjin-Hebei region, followed by domestic emissions, while the contribution of per ton emission reduced for industrial sectors subject to domestic sectors. The total contribution and contribution of per ton emission reduced for transportation and power plant were both at low level. Among industrial sectors, the iron, steel and metallurgical industry was the greatest contributor, followed by cement industry, industrial boiler, coking industry, lime and bricks industry and chemical industry. It was found that the contribution of each emission source had significant association with its primary PM2.5 emission level. The control of NOx emissions would promote the formation of PM2.5, and atmospheric vertical diffusion effect was weak during wintertime in the Beijing-Tianjin-Hebei region. As a result, emission control of various sectors was universally more effective for PM2.5 pollution mitigation in summer than in winter. Emission control in summer was significantly more effective for transportation, powerplant, cement industry, industrial boiler and lime and bricks industry. Due to considerable emissions in heating season, domestic emissions showed more contribution in winter. Agricultural sources showed greater contribution per emission reduction in winter by the reason of substantial emissions from straw open burning during this time. With respect to a certain reduction ratio of emission, future control strategies should pay more attention to industrial emissions, especially to the primary PM2.5 emissions. In details, priorities should be given to NOx and SO2 emission control for iron, steel and metallurgical industry, NOx emission control for cement industry and SO2 and NMVOC emission control for coking industry. Besides, domestic emission control should also be taken into consideration, and it will be more effective in winter.