Dopant Enhanced Conjugated Polymer Thin Film for Low-Power, Flexible and Wearable DMMP Sensor.

Conjugated polymer has the potential to be applied on flexible devices as an active layer, but further investigation is still hindered by poor conductivity and mechanical stability. Here, this work demonstrates a dopant-enhanced conductive polymer thin film and its application in dimethyl methylphosphonate (DMMP) sensor. Among five comparable polymers this work employs, poly(bisdodecylthioquaterthiophene) (PQTS12) achieves the highest doping efficiency after doped by FeCl3 , with the conductivity increasing by about five orders of magnitude. The changes in Young's modulus are also considered to optimize the conductivity and flexibility of this thin film, and finally the decay of conductivity is only 9.2% after 3000 times of mechanical bending. This work applies this thin film as the active layer of the DMMP gas sensor, which could be operated under 1 mV driving voltage and 28 nW power consumption, with a sustainable durability against bending and compression. In addition, this sensor is provided with alarm capability while exposed to the DMMP atmospheres at different hazard levels. This work expects that this general approach could offer solutions for the fabrication of low-power and flexible gas sensors, and provide guidance for next-generation wearable devices with broader applications.

Comparison of different treatment strategies in the management of endogenic caesarean scar pregnancy: a multicentre retrospective study.

BACKGROUND: The aim of this study was to evaluate the effectiveness and safety of different treatment strategies for endogenic caesarean scar pregnancy (CSP) patients. METHODS: According to Vial's standard, we defined endogenic-type CSP as (1) the gestational sac growing towards the uterine cavity and (2) a greater than 0.3 cm thickness of myometrial tissue at the caesarean scar. A total of 447 endogenic CSP patients out of 527 patients from 4 medical centres in China were enrolled in this study. A total of 120 patients were treated with methotrexate (MTX) followed by surgery, 106 received ultrasound-guided curettage directly and 221 received curettage combined with hysteroscopy. The clinical information and clinical outcomes of these patients were reviewed. Successful treatment was defined as (1) no additional treatment needed, (2) no retained mass of conception and (3) serum ß subunit of human chorionic gonadotropin (ß-hCG) level returning to a normal level within 4 weeks. The success rate was analysed based on these factors. RESULT: Among 447 patients, no significant difference was observed in baseline characteristics between groups except for foetal heartbeat. The success rate was significantly different (p<0.001) among the three groups. The highest success rate of 95.9% was noted in the hysteroscopy group, and the lowest success rate of 84.0% was noted in the curettage group. In addition, the MTX group reported the longest hospital stay and highest expenses, but the curettage group showed the shortest and lowest expenses, respectively. Nevertheless, no difference in blood loss was observed between the groups. CONCLUSION: The combination of curettage and hysteroscopy represents the most effective strategy. Pretreatment with MTX did not result in better clinical outcomes. Ultrasound-guided curettage directly should not be considered a first-line treatment choice for endogenic CSP patients.

Regional haemodynamic variables and perfusion index in the evaluation of sciatic nerve block: a prospective observational trial.

OBJECTIVE: We determined whether regional haemodynamics and perfusion index (PI) could be reliable indicators of a successful sciatic nerve block (SNB). DESIGN: Prospective observational trial. SETTING: A tertiary teaching hospital in China from April 2020 to August 2020. PARTICIPANTS: We assessed 79 patients for eligibility to participate in this study. Nine patients were excluded for not meeting our inclusion criteria, and three patients were excluded due to missing measurements at all time points. INTERVENTIONS: The patients underwent SNB. Pulsed-wave Doppler and PI measurements were performed. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome measure was the diagnostic power of regional haemodynamic change and PI to predict successful SNB. The secondary outcome measure was the effect of SNB on the regional haemodynamics and PI in the lower extremity. RESULTS: We assessed 79 patients in this study and 67 patients available for the final analysis. The SNB was successful in 59 patients and failed in eight patients. There were no significant differences in demographic characteristics between the patients with successful and failed SNB. Starting from 10 min after SNB, the peak systolic velocity (PSV), end-diastolic velocity, time-averaged maximum velocity and time-averaged mean velocity of the anterior tibial artery and posterior tibial artery of patients in the successful SNB group were significantly higher than those in the failed SNB group (p<0.05). The PSV percentage increase at 10 min after SNB has great potential to predict the block success. The area under the receiver operating characteristic curve (AUC) values were 0.893 (95% CI 0.7809 to 1.000) and 0.880 (95% CI 0.7901 to 0.9699). The corresponding cut-off values were 19.22 and 35.88, respectively. The PI increased during 5-45 min intervals in patients with successful SNB. The AUC for the PI percentage increases at 10 min after SNB was 0.853 (95% CI 0.7035 to 1.000), with a cut-off value of 93.09. CONCLUSION: The regional haemodynamic variables, PSV and PI in particular, can be used as alternative indicators for clinicians to evaluate the success of SNB objectively and early. TRIAL REGISTRATION NUMBER: ChiCTR2000030772.

Vitamin D3 Supplementation Attenuates Surgery-Induced Neuroinflammation and Cognitive Impairment by Regulating NLRP3 Inflammasome in Mice.

Neuroinflammation plays a dominant role in the progression of postoperative cognitive dysfunction (POCD). Vitamin D has been known to have important regulatory functions in inflammation and immune response. The NOD-like receptor protein 3 (NLRP3) is an essential inflammasome in the inflammatory response and could be activated by anesthesia and surgery. In this study, male C57BL/6 mice aged 14-16 months were given VD3 for 14 days straight before having an open tibial fracture surgery. The animals were either sacrificed to obtain the hippocampus or tested in a Morris water maze test. Western blot was employed to estimate the levels of NLRP3, ASC, and caspase-1, immunohistochemistry was used to identify microglial activation, and an enzyme-linked immunosorbent assay was used to measure the expression of IL-18 and IL-1ß, while using the corresponding assay kits to assess ROS and MDA levels to reflect the oxidative stress status. We showed that VD3 pretreatment significantly improved surgery-induced memory and cognitive dysfunctions in aged mice, which was linked to the inactivation of the NLRP3 inflammasome and the inhibition of neuroinflammation. This finding provided a novel preventative strategy for clinically reducing postoperative cognitive impairment in elderly surgical patients. This study has some limitations. Gender differences in the effects of VD3 were not considered, and only male mice were used. Additionally, VD3 was given as a preventative measure; however, it is unknown whether it has any therapeutic benefits for POCD mice. This trial is registered with ChiCTR-ROC-17010610.

Ropivacaine Prevents the Activation of the NLRP3 Inflammasome Caused by High Glucose in HUVECs.

Endothelial dysfunction caused by high glucose is recognized as an important event in the pathogenesis of diabetes-related vascular complications. Ropivacaine is considered to have the best safety profile among the commonly used amide local anesthetics, but the extent of its actions remains incompletely understood. Here, we used human umbilical vein endothelial cells exposed to high glucose to explore the effects of ropivacaine on oxidative stress and markers of inflammation. Ropivacaine treatment exerted significant beneficial effects by rescuing oxidative stress and downregulating interleukin (IL)-1ß and IL-18. We also found that ropivacaine could inhibit the secretion of the high-mobility group box 1 protein and improve cell viability. Importantly, sirtuin-1 (SIRT1) knockdown experiments show that the inhibitory effects of ropivacaine against NLRP3 inflammasome activation are dependent on SIRT1. Taken together, these results demonstrate the potential of ropivacaine as a promising therapy against diabetic endothelial dysfunction.

Distribution and leaching behavior of organophosphorus and brominated flame retardants in soil in Chengdu.

A total of 29 surface farmland soil samples were collected to investigate the spatial distribution and composition characteristics of 13 organophosphorus flame retardants (OPFRs), 11 polybrominated diphenyl ethers (PBDEs), and 8 novel brominated flame retardants (NBFRs) in Chengdu, China. The OPFRs were widely detected in the farmland soil with concentrations ranging from 2.92 to 160 ng g-1 dry weight (dw). BDE-209 was found with a concentration range of n.d. to 50.4 ng g-1 dw, and was the main PBDE congener accounting for 90% of ΣPBDEs in the surface farmland soil. In the case of NBFRs, only TBB and BTBPE were detected in the farmland soil from rural areas of Chengdu. There was no obvious spatial distribution of the OPFRs among different administrative regions in Chengdu (p > 0.05), but the maximum concentration of OPFRs was found in a furniture production area. Leaching experiments showed that the concentration of most of the investigated OPFRs in two kinds of soils with different mechanical compositions and TOC contents decreased with the increase of soil depth. Addition of DOM could decrease the OPFR levels in the leachate by less than 25%, with the exception of TCPP, which decreased by up to 45%. More importantly, TCEP and TCPP exhibited stronger mobility than the other OPFRs in soil, and the migration capacity of TCPP was more sensitive to the DOM level, indicating that TCEP might more easily migrate from soil to groundwater in the nature.

[Effects of the Veterinary Antibiotic Sulfamethazine on N2O Emissions and the Associated Microbiological Mechanism in a Rice Field].

Veterinary antibiotics can enter into croplands with animal excrement and can have effects on nitrification and denitrification processes in the agricultural soils. A field experiment was conducted to evaluate the effect of sulfamethazine (SMZ) on N2O emissions, nitrification, denitrification, and related functional gene abundances within a paddy field. Five treatments were used in the experiment, namely, no fertilizer and no antibiotics applied (CK), and pig manure used as basal fertilizer plus urea applied as topdressing with the addition of 0, 5, 15, and 30 mg·kg-1 SMZ (SMZ0, SMZ5, SMZ15, and SMZ30, respectively). Soil and gas samples were collected and analyzed periodically throughout the rice growing season. The results showed that the SMZ did not change the seasonal pattern of N2O emissions. During the entire observation period, there was a significant difference in N2O fluxes between the SMZ15 and SMZ0 treatment (P<0.05), but there was no significant differences in N2O fluxes between the SMZ30, SMZ5, and SMZ0 treatment (P>0.05). Medium and high concentrations (SMZ15, SMZ30) increased the cumulative emissions of N2O at the average level, and these values were 3.47 and 4.67 times higher than that of the SMZ0 treatment, respectively; the soil NO3--N content also increased. Medium and high concentrations had a significant activation effect on the gene abundances of total soil bacteria 16S rRNA, ammonia-oxidizing archaea (AOA) amoA, and ammonia-oxidizing bacteria (AOB) amoA during the nitrification process and the gene abundances of nirK, nirS, and nosZ during the denitrification process (P<0.05), while the SMZ treatment with a low concentration had a slight inhibitory effect on the abundance of each gene. The ratios of abundance copies of 16S rRNA, AOA amoA, AOB amoA, and the genes of nirK, nirS, and nosZ treated by SMZ30, SMZ15, and SMZ0 were 1.58, 1.77, 2.15, 1.38, 1.33, 1.42, and 1.24, 1.37, 1.08, 1.65, 1.11, 1.64, respectively, at the average level. The abundance ratios of the six above genes treated by SMZ5 and SMZ0 were less than one and only 0.80, 0.99, 0.92, 0.76, 0.76, and 0.77, respectively. The N2O fluxes were significantly and positively correlated with the abundances of the nirK gene (P<0.01), thus indicating that SMZ had an effect on N2O emissions by influencing the activity of denitrifying bacteria. Therefore, the pollution of farmland by veterinary antibiotics should not be ignored, and the use of antibiotics should be controlled reasonably at the source, so as to reduce the environmental and ecological risks.

Spatial Distribution of Organophosphorus and Brominated Flame Retardants in Surface Water, Sediment, Groundwater, and Wild Fish in Chengdu, China.

The occurrence and spatial distribution of 13 organophosphorus flame retardants (OPFRs), 11 polybrominated diphenyl ethers (PBDEs), and eight novel brominated flame retardants (NBFRs) were investigated in Jinjiang river water, sediment, crucian carp, and groundwater in Chengdu, China. OPFRs were predominant and ubiquitous contaminants in the Jinjiang river water, sediment, groundwater, fish muscle, fish gills, and viscera with concentrations ranging from 19.1 to 533 ng L-1, 12.5 to 253 ng g-1, 11.7 to 149 ng L-1, 114 to 2108 ng g-1 lipid weight (lw), 220 to 638 ng g-1 lw, and 116 to 1356 ng g-1 lw, respectively. The halogenated OPFRs were the primary pollutant in the Jinjiang river water samples, whereas nonhalogenated OPFRs were the dominant OPFRs in the sediments. Brominated flame retardants were not detected in the groundwater, whereas the NBFRs detected in aquatic environment at low frequency. The ΣPBDEs ranged from n.d. to 23.4 ng L-1 and n.d. to 48.7 ng g-1 in the Jinjiang river water and sediment, respectively. BDE-209 was dominant in the sediment samples with concentrations ranging from n.d. to 47.2 ng g-1. The PBDEs levels in the muscle, gills, and viscera of the crucian carp ranged from 10.6 to 90.6 ng g-1 lw, n.d. to 75.6 ng g-1 lw, and n.d. to 219 ng g-1 lw, respectively. BDE-47, chlorinated, and alkyl OPFRs were the main contaminants in the fish samples.

Grain size distribution and exposure evaluation of organophosphorus and brominated flame retardants in indoor and outdoor dust and PM10 from Chengdu, China.

To investigate overall pollution and potential risk of 32 targets (11 PBDEs, 8 NBFRs, and 13 OPFRs) in indoor and outdoor environments, dust and PM10 samples were sampled from non-occupational and occupational zones in Chengdu, China. ∑Cl-OPFRs, BDE-209, and DBDPE were the dominant constitutes in both the non-occupational and occupational dust. Regarding the PM10, no significant differences were found between the kitchen and the living room for studied OPFRs except TDCIPP, and TCEP, TCPP, TEHP, and TCP displayed significant correlation among the kitchen, the living room and personal samples. Profiles of the OPFRs in the PM10 from occupational areas presented great variation and ranked as: ∑Aryl-OPFRs < ∑Alkyl-OPFRs < ∑Cl-OPFRs. The estimated daily intakes (EDIs) of the investigated FRs via dust suggested dust ingestion and inhalation were the main exposure route to FRs, and the total of EDIs were at least one order of magnitude lower than reference data, indicating a low risk for the general public in Chengdu. However, with increasing usage of FRs in daily goods, a long-term monitoring should be conducted.

[Effects of the Veterinary Antibiotic Sulfamethazine on Ammonia Volatilization from a Paddy Field Treated with Conventional Synthetic Fertilizer and Manure].

Veterinary antibiotics have been widely detected in croplands due to the application of animal excrements as fertilizer. However, their effects on ammonia (NH3) volatilization remain unclear. A field experiment was conducted to evaluate the effect of sulfamethazine on NH3 volatilization from a paddy field when conventional synthetic fertilizer or manure was applied as basal fertilizer. Five different treatments were conducted in this study: without application of fertilizers and antibiotics (CK), compound fertilizer used as basal fertilizer with and without the addition of sulfamethazine (CF+SD and CF respectively), and pig manure used as base fertilizer with and without the addition of sulfamethazine (CM+SD and CM respectively). Urea was used for topdressing in the CF, CF+SD, CM, and CM+SD treatments. The results showed that regardless of the fertilizer type applied, sulfamethazine did not affect the seasonal pattern of NH3volatilization. However, it promoted the NH3 volatilization rate in the topdressing stage significantly (P<0.01). During the observation period, the proportions of applied N lost as NH3-N in the CF+SD and CM+SD treatments were 1.65 and 2.78 times higher than those in the CF and CM treatments, respectively. The promoting effect of sulfamethazine was more obvious in the pig manure treatment than in the compound fertilizer treatment. Sulfamethazine significantly increased the soil urease activity (P<0.05). Furthermore, the NH3 volatilization rate was positively correlated with urease activity and soil ammonia nitrogen content (P<0.05). This indicates that sulfamethazine can increase the NH3 volatilization rate by changing the soil urease activity and inorganic nitrogen content. Controlling the misuse of veterinary antibiotics and environmental and ecological risks posed by the antibiotic residues in farmland excrements are urgent problems in China that need to be solved.

Assessment of reactive nitrogen mitigation potential of different nitrogen treatments under direct-seeded rice and wheat cropping system.

The reactive nitrogen (Nr) pollution is a serious environmental problem. A wise application of nitrogen fertilizer is important for mitigating Nr loss. Field experiments were undertaken during the direct-seeded rice and winter-wheat growing seasons from 2014 to 2015 in Nanjing, one of the typical rice-wheat rotation regions in China, to evaluate the potential of different nitrogen fertilizers for mitigating Nr (N2O, NH3 emissions, and NO3- leaching) losses. Seven different fertilizer treatments were included in this study: a no fertilizer treatment (NF), conventional fertilizer (CF), urea-ammonium mixed nitrogen fertilizer (UA), stabilized urea (UHD; urea + hydroquinone + dicyandiamide), sulfur-coated urea (SCU), urea formaldehyde (UF) and organic fertilizer (OF). In comparison with the CF, all the fertilizer treatments except for UA decreased NH3 volatilization by 14.5-36.0% (p < 0.05), while none of the N fertilizers had an obvious mitigation effect on N2O emissions and NO3- leaching during the rice and wheat seasons. Further analyses showed that the UHD, UF and OF treatments reduced the yield-scaled Nr loss (NLI) by 32.6-42.5% for the rice season and by 15.5-34.5% for the wheat season as compared to the CF; other treatments relative to CF had no obvious effect with regard to lowering the NLI. UHD, UF and OF could be adopted as an effective mitigation alternative to reduce Nr loss and maintain crop yield in future rice/wheat production. Graphical abstract ᅟ.

Distribution and risk assessment of metals in water, sediments, and wild fish from Jinjiang River in Chengdu, China.

To evaluate the distribution patterns, degrees of contamination, and ecological risks of 15 metals (Cd, Pb, Sb, Sn, Tl, Mo, Cr, Mn, Ni, Cu, Zn, As, V, Co, and Se), a total of 26 paired water and sediment samples as well as 7 fish samples were collected in Jinjiang River, Chengdu, China. The metal forms of the sediments were analyzed using BCR three-step sequential extraction procedures, and the metal contents of the samples were determined by ICP-MS. Four environmental indices including the geo-accumulation index, bioconcentration factor, biota-sediment accumulation factor, and the potential ecological risk index were calculated to evaluate pollution level and eco-risk of the metals. Based on the current study, Mn and Cd were preferentially associated with the exchangeable fraction, Cu and Pb were primarily in the reducible fraction, while the other metals were mainly found in the residual fraction. With the exception of Sb and Mo, the BCF values of the metals were greater than 100, especially for Zn, which had the highest BCF value (74200), suggesting that these metals had higher bioconcentration ability. Based on the geo-accumulation index and the potential ecological risk index (RI) calculated in this study, the middle reaches of Jinjiang River present moderate to severe metal pollution, and moderate to considerable potential ecological risk, especially for the risk of Cd, which should be paid more attention in the future. While non-pollution level and low ecological risk of the metals were found in the upper and lower reaches of Jinjiang River.

Analysis of methylation profiling data of hyperplasia and primary and metastatic endometrial cancers.

OBJECTIVE: Endometrial cancer is a prevalent cancer, and its metastasis causes low survival rate. This study aims to utilize DNA methylation data to investigate the mechanism of the development and metastasis of endometrial cancer. STUDY DESIGN: Methylation profiling data were down-loaded from Gene Expression Omnibus, including 8 hyperplasias, 33 primary and 53 metastatic endometrial cancers. COHCAP package and annotation files were utilized to identify differentially methylated genes (DMGs) and CpG islands between the three different endometrial diseases. STRING database and Cytoscape were used to analyze and visualize protein-protein interactions (PPIs) between DMGs. CytoNCA plugin was utilized to identify key nodes in PPI network. RESULTS: A total of 610, 1076, and 501 DMGs were identified between primary endometrial cancer and hyperplasia, metastatic endometrial cancer and hyperplasia, as well as metastatic and primary endometrial cancers, respectively. For the three DMG sets, 53 common hypermethylated DMGs (e.g. PAX6 and INSR) and 6 common hypomethylated DMGs (e.g. PRDM8, KLHL14, and DUSP6) were found. For primary-hyperplasia DMG set and metastasis-hyperplasia DMG set, 527 common DMGs were found. For these common DMGs, a PPI network involving 692 PPIs was constructed. For DMGs between metastatic and primary endometrial cancers, a PPI network involving 673 PPIs was established, with PAX6 and INSR in the top 20 DMGs in both networks. PRDM8, KLHL14, and DUSP6 had hypomethylated CpG islands. CONCLUSION: DMGs comparison, PPI network analysis, and analysis of differentially methylated CpG islands indicated that PAX6, INSR, PRDM8, KLHL14, and DUSP6 might participate in the development and metastasis of endometrial cancer.

Long non-coding RNA SNHG1 is an unfavorable prognostic factor and promotes cell proliferation and migration by Wnt/ß-catenin pathway in epithelial ovarian cancer.

Long non-coding RNAs (lncRNA) have been shown to serve critical roles in human cancers development, including epithelial ovarian cancer (EOC). Here, we identified a novel lncRNA SNHG1, which was markedly upregulated in human EOC tissues and cell lines. High SNHG1 expression was associated with aggressive clinical features and poor prognosis of EOC patients. Moreover, the downregulation of SNHG1 remarkably inhibited the EOC cells proliferation, migration and invasion, suppressed S-phase entry in vitro, and repressed tumor growth in vivo. In contrast, overexpression of SNHG1 could promote the aggressive behaviors of EOC cells. Furthermore, through western blot, we found that SNHG1 enhanced the expression of several downstream genes in Wnt/ß-catenin pathway. Our findings demonstrated that the dysregulation of SNHG1 is implicated in EOC tumorigenesis and progression through regulating Wnt/ß-catenin pathway.

Inhibition of mammalian target of rapamycin activation in the rostral anterior cingulate cortex attenuates pain-related aversion in rats.

Pain is a complex experience that comprises both sensory and affective dimensions. Mammalian target of rapamycin (mTOR) plays an important role in the modulation of neuronal plasticity associated with the pathogenesis of pain sensation. However, the role of mTOR in pain affect is unclear. Using a formalin-induced conditioned place avoidance (F-CPA) test, the current study investigated the effects of the mTOR specific inhibitor rapamycin on noxious stimulation induced aversion in the rostral anterior cingulate cortex (rACC). Intraplantar injection of 5% formalin was associated with significant activation of mTOR, as well as p70 ribosomal S6 protein (p70S6K), its downstream effector, in the rACC. The inhibition of mTOR activation with rapamycin disrupted pain-related aversion; however, this inhibition did not affect formalin-induced spontaneous nociceptive behaviors in rats. These findings demonstrated for the first time that mTOR and its downstream pathway in the rACC contribute to the induction of pain-related negative emotion.

[Assessment of Gaseous Nitrogen (NH3 and N2O) Mitigation After the Application of a Range of New Nitrogen Fertilizers in Summer Maize Cultivation].

In order to evaluate the potential of a range of new nitrogen fertilizers in comparison with the conventional fertilization to mitigate ammonia (NH3) and nitrous oxide (N2O) emissions, a field experiment was conducted to investigate NH3 volatilization and N2O emissions from the summer maize field and the relevant driving factors under the different nitrogen fertilizer treatments. Five new varieties of nitrogen fertilizers including the urea ammonium (UA), stability urea with dicyandiamide and hydroquinone (UHD), sulfur coated urea (SCU), urea formaldehyde compound fertilizer (UF) and organic fertilizer (OF) were applied in this experiment, and conventional fertilization (compound fertilizer + urea, CK) was used as the control. The nitrogen amount of 300 kg·hm-2 was applied in all treatments. Correlation analysis results showed that both NH3 volatilization and N2O emissions were influenced by environmental factors. They were negatively correlated with soil water-filled pore space (P<0.05). Moreover, N2O emissions were positively correlated with soil nitrate nitrogen (P<0.01). Regression analysis showed that N2O emissions were mainly determined by the soil nitrate content, while NH3 volatilization was mainly dependent on the values of soil ammonium nitrogen. Compared with CK, in addition to UA, other fertilizer treatments decreased the NH3 volatilization, especially the UF and OF treatments decreased NH3 volatilization by up to 37%-43%, while all treatments had no significant difference in N2O emissions. Considering the total gaseous nitrogen losses (NH3 volatilization + N2O emissions), in comparison with CK, the UHD, SCU, UF and OF were reduced by 9%, 5%, 30% and 23%, respectively, while the UA was increased by 3%. Therefore, considering environmental benefit under this experimental condition,urea formaldehyde compound fertilizer and organic fertilizer were more suitable for maize cultivation.

[Nitrogen Loss Through Different Ways in Cropland Under Conventional Fertilization: An In-situ Study of Summer Maize Season in the Middle and Lower Reaches of the Yangtze River].

In order to better understand the characteristics of nitrogen loss through different pathways under conventional fertilization conditions, a field experiment was conducted to investigate the variations of N2O emission, NH3 volatilization, N losses through surface runoff and leaching caused by the application of nitrogen fertilizers during summer maize growing season in the Middle and Lower reaches of the Yangtze River, China. Our results showed that when compound fertilizer was used as basal fertilizer at the nitrogen rate of 150 kg.hm-2, and urea with the same level of fertilizing as topdressing, the N2O emission coefficient in the entire growing season was 3. 3%, NH3 volatilization loss rate was 10. 2%, and nitrogen loss rate by leaching and surface runoff was 11. 2% and 5. 1%, respectively. In addition, leaching was the main pathway of nitrogen loss after basal fertilizer, while NH, volatilization and nitrogen leaching accounted for the majority of nitrogen loss after topdressing, which suggested that nitrogen loss from different pathways mainly depended on the type of nitrogen fertilizer. Taken together, it appears to be effective to apply the new N fertilizer with low ammonia volatilization instead of urea when maize needs topdressing, so as to reduce N losses from N fertilizer.

[Soil biochemical characteristics in different ecological systems and their relationships with soil respiration and N2O emission].

The biochemical characteristics of soil in different ecological system and their effects on soil respiration (CO2) and nitrous oxide (N2O) emission were investigated by an indoor incubation method. The results showed that the biochemical characteristics of soils in the different ecosystems and CO2 and N2O emissions from different soils greatly varied with each other. In general, the highest abundance of bacteria was found in the orchard soil, the highest abundance of actinomycetes occurred in the meadows and the highest abundance of fungi appeared in the woodlands. The abundance of bacteria or actinomycetes in the bamboo soil was the lowest among all soils, and the orchard soil had the lowest content of fungi. The contents of soil microbial biomass carbon and nitrogen generally followed the order of orchard soil > woodland > cropland. Moreover, cumulative CO2 and N2O emissions from the different soils followed the order of orchard soil > bamboo soil > farmland > woodland > grassland and farmland > orchard > grassland > woodland > bamboo soil, respectively. Correlation analysis indicated that there was positive correlations between the abundance of soil bacteria and the contents of microbial biomass carbon and nitrogen, as well as between the abundance of soil fungi and the soil total nitrogen content (P < 0.05), while the abundance of soil actinomycosis was positively correlated with soil organic carbon and total nitrogen contents (P < 0.01). The soil bacteria, microbial carbon and nitrogen had a significant positive impact on soil respiration (P < 0.05), and soil bacteria, actinomycetes, fungi and ammonium nitrogen had the same impact on N2O emissions (P < 0.05). Stepwise regression analysis suggested that soil respiration could be quantitatively determined by a linear combination of soil bacteria and soil pH, while N2O emission was mainly dependent on the values of soil bacteria and ammonium nitrogen.

Surgical morbidity and oncologic results after concurrent chemoradiation therapy for advanced cervical cancer.

OBJECTIVE: To evaluate the surgical morbidity and oncologic results after concurrent chemoradiotherapy (CCRT) followed by completion surgery for advanced cervical carcinoma. METHODS: The present retrospective analysis included 192 patients with advanced cervical cancer (stage IIB-IVA) treated with CCRT followed by surgery and 186 control patients without completion surgery. Disease-free and overall survival rates were compared. RESULTS: Of the patients who underwent surgery, 27 (14.1%) had pathologic evidence of residual disease; the local control rate with CCRT was 85.9%. After a median follow-up period of 190 months, 32 (16.7%) patients who underwent completion surgery had a recurrence compared with 59 (31.7%) of those who did not. The overall survival rate among patients who underwent extrafascial hysterectomy, extended hysterectomy, or no surgery was 72.2%, 60.1%, and 45.9% at 3 years, and 53.5%, 40.7%, and 32.2% at 5 years, respectively. CONCLUSION: Surgery after CCRT for advanced cervical cancer enabled evaluation of the pathologic response to therapy, improved local disease control in patients with a partial pathologic response, and enhanced survival. The most appropriate surgical approach was extrafascial hysterectomy with pelvic lymph node dissection.

A preliminary study on the construction of double suicide gene delivery vectors by mesenchymal stem cells and the in vitro inhibitory effects on SKOV3 cells.

The aim of the present study was to investigate the efficacy of using human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) as gene delivery vectors in the treatment of ovarian cancer. Lentivectors overexpressing cytosine deaminase (CD) and herpes simplex virus thymidine kinase (HSV-tk) (pGC-FU-CD-TK) were constructed, and confirmed by enzyme digestion, DNA sequence and western blotting. Quantitative PCR (PCR) was used to verify the overexpression of the fusion gene (CD and HSV-tk). SKOV3 cells were co-cultured with MSCs/tk+CD+ at a 1:1 ratio, and were then treated with the prodrugs (GCV) and/or 5-fluorocytosine (5-FC) at different concentrations, and the cytotoxic effects were evaluated using MTT assay and flow cytometry. DNA sequencing demonstrated that the sequence of HSV-tk and CD genes were consistent with the objective sequence and western blotting verified that the constructed lentivector could produce the HSV-tk/CD gene. The packed titer was 2.00e+8 TU/ml. The pGC-FU-CD-TK could be stably transferred to hUCB­MSCs, and the infection efficiency was almost 80%. RT-PCR demonstrated that the expression levels of the HSV-tk/CD fusion gene in MSCs/tk+CD+ group was 75 times that in the negative control (P<0.05). Compared with GCV or 5-FC alone, the growth inhibition rate (GIR) was significantly higher in the combined treatment (F=85.35, P<0.05). The reconstructed MSCs/tk+CD+ vectors were capable of slowing down the growth of human SKOV3 cells in the presence of prodrugs in vitro. The use of combination chemotherapy exhibited a more significant inhibitory effect than using a single prodrug.