Dissolved organic matter accelerates microbial degradation of 17 alpha-ethinylestradiol in the presence of iron mineral

Dissolved organic matter (DOM) and iron minerals widely existing in the natural aquatic environment can mediate the migration and transformation of organic pollutants. However, the mechanism of interaction between DOM and iron minerals in the microbial degradation of pollutants deserves further investigation. In this study, the mechanism of 17 alpha-ethinylestradiol (EE2) biodegradation mediated by humic acid (HA) and three kinds of iron minerals (goethite, magnetite, and pyrite) was investigated. The results found that HA and iron minerals significantly accelerated the biodegradation process of EE2, and the highest degradation efficiency of EE2 (48%) was observed in the HA-mediated microbial system with pyrite under aerobic conditions. Furthermore, it had been demonstrated that hydroxyl radicals (HO•) was the main active substance responsible for the microbial degradation of EE2. HO• is primarily generated through the reaction between hydrogen peroxide secreted by microorganisms and Fe(II), with aerobic conditions being more conducive. The presence of iron minerals and HA could change the microbial communities in the EE2 biodegradation system. These findings provide new information for exploring the migration and transformation of pollutants by microorganisms in iron-rich environments.

Does Pollyanna hypothesis hold true in death narratives? A sentiment analysis approach

Pollyanna hypothesis claims that human beings have a universal tendency to use positive words more frequently and broadly than negative words. The present study aims to test Pollyanna hypothesis in medical death narratives at both lexical and text levels by using sentiment analysis and emotion detection methods, and to qualitatively analyze the contextual use of emotion words to deepen the understanding of doctors' emotions. Sentiment analysis showed a strong token-based linguistic positivity and a weak type-based negativity bias at the lexical level, and a general positivity bias at the text level, despite the gender of the doctors. Emotion detection discovered three prominent emotions of "joy", "sadness", and "anger", and a greater diversity of negative emotions in contrast to positive emotions in medical death narratives. Contextual analysis revealed that emotion words associated with joy were primarily observed in contexts related to doctors' actions and behaviors aiming to benefit others and promote social wellbeing. Emotion words associated with sadness and anger were chiefly employed to describe situations involving patients' death and doctors' attitudes towards death. The results confirm Pollyanna hypothesis at both token-based lexical level and text level and falsify the hypothesis at type-based lexical level. Possible explanations are explored by contextual analysis, and theoretical analysis from the perspectives of cognitive linguistics and social psychology. The findings are expected to enrich the understanding of Pollyanna hypothesis as well as the junior doctors' emotional responses to clinical deaths.

LINC01094 promotes human nasal epithelial cell epithelial-to-mesenchymal transition and pyroptosis via upregulating HMGB1

BACKGROUND

Excessive epithelial-to-mesenchymal transition (EMT) of nasal epithelial cells (NECs) play a prominent role in chronic rhinosinusitis with nasal polyps (CRSwNP) pathogenesis. Long intergenic non-coding RNA 01094 (LINC01094) was previously reported to be overexpressed in CRSwNP, while the regulatory mechanism by which LINC01094 regulates CRSwNP progression remains unclear. Our study aimed to investigate the role of LINC01094 in CRSwNP development.

METHODS

hNEC were isolated from tissues of controls and CRSwNP patients and stimulated with interleukin (IL)-13. 3-(4, 5-Dimethylthiazolyl2)-2, 5-diphenyltetrazolium bromide (MTT) assay was employed to analyze hNEC viability. Flow cytometry was employed to analyze pyroptosis. Immunofluorescence was employed to analyze Snail nuclear translocation. The interactions between LINC01094, fused in sarcoma (FUS) and high mobility group box-1 (HMGB1) were analyzed by RNA immunoprecipitation (RIP) and RNA pull-down assays.

RESULTS

LINC01094 and EMT-related proteins were markedly upregulated in nasal polyp tissues of CRSwNP. LINC01094 knockdown inhibited IL-13-induced hNEC EMT and pyroptosis. LINC01094 promoted HMGB1 expression in CRSwNP by binding with FUS. HMGB1 promoted Snail nuclear import in GSK-B phosphorylation-dependent manner.

CONCLUSION

LINC01094 facilitated hNEC EMT and pyroptosis in CRSwNP by activating the HMGB1/GSK-B Snail axis, which suggested that LINC01094 might serve as a biomarker and therapeutic target in CRSwNP.

The disinfectant residues promote the leaching of water contaminants from plastic pipe particles

Disinfection treatment is an indispensable water purification process, but it can leave trace concentrations of disinfectant in the purified water. Disinfectants oxidation can age plastic pipes and release hazardous microplastics and chemicals into drinking water. Lengths of commercially-available unplasticized polyvinyl chloride and polypropylene random copolymer water pipe were ground into particles and exposed to micro-molar concentrations of ClO₂, NaClO, trichloroisocyanuric acid, or O₃ for up to 75 days. The disinfectants aged the plastic and changed its surface morphology and functional groups. Meanwhile, disinfectants could significantly promote the release of organic matter from plastic pipes into the water. ClO₂ generated the highest concentrations of organic matter in the leachates from both plastics. Plasticizers, antioxidants and low molecular weight organic matter were detected in all of the leachates. Leachate samples inhibited the proliferation of CT26 mouse colon cancer and induced oxidative stress in the cells. Even trace concentrations of residual disinfectant can constitute a drinking water risk.

Effects of water constituents on the stability of gas diffusion electrode during electrochemical hydrogen peroxide production for water and wastewater treatment

Electrochemically producing hydrogen peroxide (H₂O₂) from oxygen reduction reaction (ORR) with natural air diffusion electrode (NADE) is an attractive way to supply H₂O₂ for decentralized water treatment. In this study, the stability of NADE during H₂O₂ electroproduction in varying water matrices were evaluated, including synthetic electrolyte solutions (0.05 M Na₂SO₄) with or without calcium ions (Ca²⁺, 200 mg/L) and/or humic acid (HA, 40 mg/L), as well as a selected municipal wastewater (92.7 mg/L Ca²⁺, 3.6 mg/L Mg²⁺, and 23.9 mg/L total organic carbon). The results show that NADEs maintained a good stability during H₂O₂ electroproduction in Na₂SO₄ solutions regardless of the presence of HA. However, Ca²⁺ (and Mg²⁺) could form significant amounts of mineral precipitates on the surface and in the internal pores of NADEs during H₂O₂ electroproduction. These mineral precipitates can negatively influence H₂O₂ production by impeding the oxygen, electron, and proton transfer processes involved in ORR to H₂O₂. Moreover, the mineral precipitates shifted the NADEs from hydrophobic to hydrophilic, which may promote H₂O₂ reduction to H₂O at the NADEs. Consequently, the apparent current efficiencies of H₂O₂ production decreased substantially from initially ∼90% to 50%-70% as the NADEs were continuously used for 60 h in the Ca-containing solutions and selected wastewater. These results indicate that water constituents that are commonly present in real water matrices, especially Ca²⁺, can cause serious deterioration of NADE stability during H₂O₂ electroproduction. Therefore, proper strategies are needed to mitigate electrode fouling during H₂O₂ electroproduction with NADEs in practical water and wastewater treatment.

Assessment of the validity of the quenching method for evaluating the role of reactive species in pollutant abatement during the persulfate-based process

Reactive species such as sulfate radicals (SO₄^•-), hydroxyl radicals (^•OH), and/or singlet oxygen (¹O₂) have often been proposed as the main reactive species for pollutant abatement during the persulfate-based process, and their relative importance is conventionally assessed by the quenching method based on an implicit fundamental assumption that the added high-concentration quenchers (e.g., tert-butanol and methanol) only scavenge their target reactive species, but do not considerably affect the other reaction mechanism of the system. To examine the validity of this assumption, this study evaluated the effects of several commonly used quenchers (tert-butanol, methanol, ethanol, isopropanol, furfuryl alcohol, and L-histidine) on the mechanism of a cobalt mediated peroxymonosulfate (Co(II)/PMS) process. The results demonstrate that besides quenching target reactive species, the added high-concentration quenchers can cause many confounding effects on the Co(II)/PMS process, e.g., accelerating PMS decomposition, interfering reactive species production, and quenching of non-target reactive species. Because of these confounding effects, the quenching method can actually lead to serious misinterpretation of the role of reactive species in pollutant abatement during the persulfate-based process. The findings of this study highlight that the underlying assumption of the quenching method is usually invalid for the persulfate-based process. Therefore, it should be cautious to apply the quenching method to investigate the mechanism of the persulfate-based process, and some debatable conclusions of prior studies obtained with the quenching method may require further verification.

[MYC and BCL-2 protein co-expression and prognosis of patients with diffuse large B-cell lymphoma: a propensity score matching analysis]

目的

探究MYC/BCL-2蛋白双表达对弥漫大B细胞淋巴瘤（DLBCL）患者预后的影响，观察纳入DA-EPOCH-R（利妥昔单抗+依托泊苷+泼尼松+长春新碱+环磷酰胺+表阿霉素）、中枢神经系统预防治疗、移植等治疗因素后，双表达是否仍是DLBCL的独立预后不良因素。

方法

回顾性收集2015−2018年在北京协和医院血液科治疗且具有可用病理结果的223例初治DLBCL患者，75例MYC/BCL-2高表达的患者归为双表达组，从148例非双表达的患者中，应用倾向性评分（PSM），根据年龄、国际预后指数（IPI）评分、治疗选择等因素进行1∶1匹配，筛选出75例作为对照组，比较两组患者总生存（OS）及无进展生存（PFS）等方面的差异。

结果

PSM后双表达组和非双表达组的3年OS率分别为（69.8±5.5）％及（77.0±4.9）％（P＝0.225），3年PFS率分别为（60.7±5.8）％及（65.3±5.5）％（P＝0.390），差异均无统计学意义。R-CHOP方案（利妥昔单抗+环磷酰胺+阿霉素+长春新碱+泼尼松）治疗的亚组分析显示，双表达和非双表达患者的3年OS率分别为（61.3±7.5）％及（77.2±5.6）％（P＝0.027），3年PFS率分别为（52.1±7.5）％及（70.6 ± 6.0）％（P＝0.040），差异均具有统计学意义。多因素Cox回归分析显示年龄、Ann Arbor分期、细胞起源（COO）分型、是否进行中枢神经系统预防、是否进行移植是DLBCL患者预后的独立影响因素（P值均<0.05），而MYC/BCL-2蛋白双表达不是预后的影响因素。

结论

MYC/BCL-2蛋白双表达在R-CHOP方案治疗下与不良预后显著相关，但在DA-EPOCH-R、移植等治疗方案下，双表达对DLBCL的不良预后影响在一定程度上得到消除。

Machine learning-based radiomic evaluation of treatment response prediction in glioblastoma

AIM

To investigate machine learning based models combining clinical, radiomic, and molecular information to distinguish between early true progression (tPD) and pseudoprogression (psPD) in patients with glioblastoma.

MATERIALS AND METHODS

A retrospective analysis was undertaken of 76 patients (46 tPD, 30 psPD) with early enhancing disease following chemoradiotherapy for glioblastoma. Outcome was determined on follow-up until 6 months post-chemoradiotherapy. Models comprised clinical characteristics, O⁶-methylguanine-DNA methyltransferase (MGMT) promoter methylation status, and 307 quantitative imaging features extracted from enhancing disease and perilesional oedema masks on early post-chemoradiotherapy contrast-enhanced T1-weighted imaging, T2-weighted imaging (T2WI), and apparent diffusion coefficient (ADC) maps. Feature selection was performed within bootstrapped cross-validated recursive feature elimination with a random forest algorithm. Naive Bayes five-fold cross-validation was used to validate the final model.

RESULTS

Top selected features included age, MGMT promoter methylation status, two shape-based features from the enhancing disease mask, three radiomic features from the enhancing disease mask on ADC, and one radiomic feature from the perilesional oedema mask on T2WI. The final model had an area under the receiver operating characteristics curve (AUC) of 0.80, sensitivity 78.2%, specificity 66.7%, and accuracy of 73.7%.

CONCLUSION

Incorporating a machine learning-based approach using quantitative radiomic features from standard-of-care magnetic resonance imaging (MRI), in combination with clinical characteristics and MGMT promoter methylation status has a complementary effect and improves model performance for early prediction of glioblastoma treatment response.

Evaluation of the concentration and contribution of superoxide radical for micropollutant abatement during ozonation

Due to the fast reaction of superoxide radical (O₂^•-) with ozone (O₃), it has been suggested that O₂^•- is present at very low concentrations during ozonation. Therefore, while O₂^•- has been considered a critical chain carrier for promoting O₃ decomposition to hydroxyl radicals (•OH), the direct reactions of O₂^•- with micropollutants have been assumed to be insignificant during ozonation. In this study, we monitored the exposures of O₃, •OH, and O₂^•- by following the depletion of O₃, p-chlorobenzoic acid (pCBA, as •OH probe), and tetrachloromethane (CCl₄, as O₂^•- probe) during ozonation of various water matrices (surface water, groundwater, and secondary wastewater effluent). For a given water matrix, the ratio between •OH and O₃ exposures (R_ct), O₂^•- and O₃ exposures (R_SO), as well as O₂^•- and •OH exposures (R_SH) remained almost constant over the entire reaction time. This suggests that during ozonation, the ratios between the transient concentrations of •OH and O₃, O₂^•- and O₃, and O₂^•- and •OH were also constant and equaled to the R_ct, R_SO, and R_SH, respectively. Based on the O₃, •OH, and O₂^•- exposures observed during ozonation, a chemical kinetic model was proposed to simulate the abatement of ten ozone-resistant micropollutants in the three water matrices by ozonation. The results indicate that due to the higher concentrations of O₂^•- than •OH (R_SH = ~5-8), the reactions with O₂^•- played a non-negligible or even dominant role in the abatement of some micropollutants that have similar or higher O₂^•- reactivity than •OH reactivity (e.g., tetrachloroethylene, chloroform, and PFOA). Compared with the previous model that neglected the contribution of O₂^•- to micropollutant abatement, the proposed model more accurately simulated the abatement efficiencies of the test micropollutants during ozonation. These results indicate that the proposed model can provide a useful tool for the generalized prediction of micropollutant abatement by ozonation.

Nilpotent fuzzy lie ideals

In this paper, we introduce a new definition for nilpotent fuzzy Lie ideal, which is a well-defined extension of nilpotent Lie ideal in Lie algebras, and we name it a good nilpotent fuzzy Lie ideal. Then we prove that a Lie algebra is nilpotent if and only if any fuzzy Lie ideal of it, is a good nilpotent fuzzy Lie ideal. In particular, we construct a nilpotent Lie algebra via a good nilpotent fuzzy Lie ideal. Also, we prove that with some conditions, every good nilpotent fuzzy Lie ideal is finite. Finally, we define an Engel fuzzy Lie ideal, and we show that every Engel fuzzy Lie ideal of a finite Lie algebra is a good nilpotent fuzzy Lie ideal. We think that these notions could be useful to solve some problems of Lie algebras with nilpotent fuzzy Lie ideals.

Kinetics and mechanism of thiamethoxam abatement by ozonation and ozone-based advanced oxidation processes

In this study, the abatement of neonicotinoid insecticide, thiamethoxam, by single ozonation, ozone/ultraviolet (O₃/UV) and electro-peroxone (EP) process was evaluated. The second-order rate constants for the reaction of thiamethoxam with O₃ and hydroxyl radical (OH) at pH 7 were determined to be 15.4 M^-1 s^-1 and 3.9 × 10⁹ M^-1 s^-1, respectively. The degradation pathways of thiamethoxam were proposed based on quantum chemical calculations and transformation products were identified using chromatographic and mass-spectrometric techniques. The acute and chronic toxicity of thiamethoxam and its major TPs to various aquatic organisms were assessed. With typical ozone doses applied in water treatment (≤5 mg/L), thiamethoxam was abated by only ∼16-32 % in two real water matrices (groundwater and surface water) during single ozonation, but by ∼100 % and >70 % during the O₃/UV and EP treatment, respectively. The energy demand to abate 90 % thiamethoxam in the two water matrices was generally comparable for single ozonation and the EP process (∼0.14 ± 0.03 kW h/m³), but higher for the O₃/UV process (0.21-0.22 kW h/m³). These results suggest that single ozonation is unable to sufficiently abate thiamethoxam under typical conditions of water treatment. Therefore, ozone-based advanced oxidation processes are needed to enhance thiamethoxam abatement.

[Analysis of infection status and recombination types of norovirus in patients with acute gastroenteritis in the Ningxia Hui Autonomous Region from 2016 to 2017]

Objective: To analyze the infection status and recombination of Norovirus in patients with acute gastroenteritis in Ningxia. Methods: The specimens of 10 sentinel hospitals in Ningxia were collected from 2016 to 2017. Real-time quantitative PCR was used for nucleic acid detection. GⅡ-positive samples were amplified by RT-PCR for the RdRp and Capsid regions, then sequenced and genotyped. Evolution analysis was performed using software such as MEGA-X, and recombination analysis was performed using Simplot 3.5.1 and RDP4. Results: The age of the 2 334 cases was 1.42 (0.68, 7.69) years old, 1 133 cases in 2016 and 1 201 cases in 2017, 1 343 and 991 cases for males and females respectively. The positive rate of Norovirus GⅠ genogroup was 0.86% (20/2 334), and GⅡ genogroup was 14.82% (346/2 334). A total of 78 recombinant strains were sequenced and 12 recombinant types were found. GⅡ.Pe/GⅡ.4Sydney_2012 and GⅡ.P12/GⅡ.3 were the main epidemic strains, accounting for 35.90% (28 strains) and 32.05% (25 strain) respectively, followed by GⅡ.P16/GⅡ.2 accounting for 12.82% (10 strains). Among them,GⅡ.P7/GⅡ.6 (2 strains), GⅡ.P12/GⅡ.3 (6 strains), GⅡ.P16/GⅡ.1 (2 strains), GⅡ.P16/GⅡ.2 (5 strains), GⅡ.Pe/GⅡ.4 (7 strains) were detected for the first time in Ningxia. Recombinant strains were all intergenotype recombination, and the recombination breakpionts were all located within ORF1. Conclusion: Norovirus infection in Ningxia area was mainly in GⅡ genogroup from 2016 to 2017, and most of them were recombinant strains. GⅡ.Pe/GⅡ.4Sydney_2012 and GⅡ.P12/GⅡ.3 were the main epidemic strains, followed by GⅡ.P16/GⅡ. 2.

Multi-modular engineering for renewable production of isoprene via mevalonate pathway in Escherichia coli

AIMS

To establish the biotechnology platforms for production of bio-based chemicals in various micro-organisms is considered as a promising target to improve renewable production of isoprene.

METHODS AND RESULTS

In this study, we heterologously expressed the mevalonate (MVA) isoprene biosynthesis pathway, and explored three strategies of increasing isoprene production in Escherichia coli. We first manipulated the expression levels of the MVA pathway genes through changing the gene cassettes and promoters. To introduce cofactor engineering, we then overexpressed NADP-dependent glyceraldehyde-3-phosphate dehydrogenase gene from Clostridium acetobutylicum to supply available NADPH. To reduce the inhibitory by-product accumulation, we finally knocked out acetate-producing genes, phosphate acetyl transferase and pyruvate oxidase B in E. coliJM109 (DE3), decreasing acetate accumulation 89% and increasing isoprene production 39%. The strategies described here finally increased the isoprene titre to 92 mg l^-1 in two-gene deletion strain JMAB-4T7P1Trc, increasing 2·6-fold comparing to strain JM7T7.

CONCLUSION

The multimodularly engineering approaches including promoter engineering, cofactor engineering and by-product reducing could be used to improve isoprene production in E. coli.

SIGNIFICANCE AND IMPACT OF THE STUDY

The metabolic strategies in this study show us directions for further studies to promote transformation of renewable sources to isoprene.

Comparison of pharmaceutical abatement in various water matrices by conventional ozonation, peroxone (O3/H2O2), and an electro-peroxone process

Pharmaceutical abatement in a groundwater (GW), surface water (SW), and secondary effluent (SE) by conventional ozonation, the conventional peroxone (O₃/H₂O₂), and the electro-peroxone (E-peroxone) processes was compared in batch tests. SE had significantly more fast-reacting dissolved organic matter (DOM) moieties than GW and SW. Therefore, O₃ decomposed much faster in SE than in GW and SW. At specific ozone doses of 0.5-1.5 mg O₃/mg dissolved organic carbon (DOC), the application of O₃/H₂O₂ and E-peroxone process (by adding external H₂O₂ stocks or in-situ generating H₂O₂ from cathodic O₂ reduction during ozonation) similarly enhanced the OH yield from O₃ decomposition by ∼5-12% and 5-7% in GW and SW, respectively, compared to conventional ozonation. In contrast, due to the slower reaction kinetics of O₃ with H₂O₂ than O₃ with fast-reacting DOM moieties, the addition or electro-generation of H₂O₂ hardly increased the OH yield (<4% increases) in SE. Corresponding to the changes in the OH yields, the abatement efficiencies of ozone-resistant pharmaceuticals (ibuprofen and clofibric acid) increased evidently in GW (up to ∼14-18% at a specific ozone dose of 1.5 mg O₃/mg DOC), moderately in SW (up to 6-10% at 0.5 mg O₃/mg DOC), and negligibly in SE during the O₃/H₂O₂ and E-peroxone treatment compared to conventional ozonation. These results indicate that similar to the conventional O₃/H₂O₂ process, the E-peroxone process can more pronouncedly enhance O₃ transformation to OH, and thus increase the abatement efficiency of ozone-resistant pharmaceuticals in water matrices exerting relatively high ozone stability (e.g., groundwater and surface water with low DOM contents). Therefore, by installing electrodes in existing ozone reactors, the E-peroxone process may provide a convenient way to enhance pharmaceutical abatement in drinking water applications, where groundwater and surface water with low DOM contents are used as the source waters.

Adsorption of heavy metal from aqueous solution by dehydrated root powder of long-root Eichhornia crassipes

The root powder of long-root Eichhornia crassipes, as a new kind of biodegradable adsorbent, has been tested for aqueous adsorption of Pb, Zn, Cu, and Cd. From FT-IR, we found that the absorption peaks of phosphorous compounds, carbonyl, and nitrogenous compounds displayed obvious changes before and after adsorption which illustrated that plant characteristics may play a role in binding with metals. Surface properties and morphology of the root powders have been characterized by means of SEM and BET. Energy spectrum analysis showed that the metals were adsorbed on root powders after adsorption. Then, optimum quantity of powder, pH values, and metal ion concentrations in single-system and multi-system were detected to discuss the characteristics and mechanisms of metal adsorption. Freundlich model and the second-order kinetics equation could well describe the adsorption of heavy metals in single-metal system. The adsorption of Pb, Zn, and Cd in the multi-metal system decreased with the concentration increased. At last, competitive adsorption of every two metals on root powder proved that Cu and Pb had suppressed the adsorption performance of Cd and Zn.

Adaptive behaviour of Chinese boys with fragile X syndrome

BACKGROUND

Adaptive behaviour is closely related to quality of life in children with intellectual disability (ID), but little is known about the adaptive behaviour of children with fragile X syndrome (FXS) in China.

METHOD

In boys with FXS, the adaptive behaviours in six domains, including self-dependence, locomotion, work skills, communication, socialisation and self-management, were assessed by the Infants-Junior Middle School Students Social-life Abilities Scale. In addition, we compared the adaptive skills of boys with FXS to those of three control groups of boys, including boys with Down syndrome (DS) and typically developing (TD) boys matched by chronological age (CA) or mental age (MA). The profile of the adaptive behaviour of boys with FXS is discussed in detail.

RESULTS

Compared to boys with DS, boys with FXS obtained lower scores in three domains in adaptive behaviour, including work skills, socialisation and self-management skills; boys with FXS had better scores in self-dependence and locomotion skills than boys matched for MA; as expected, boys with FXS had significantly poorer adaptive skills in all six domains assessed compared to CA boys.

CONCLUSION

The development of adaptive skills in boys with FXS was worse than that of boys with DS. The profile of the adaptive behaviour of boys with FXS establishes a basis for the development of targeted interventions to promote social development in this population.

Mechanisms of enhanced total organic carbon elimination from oxalic acid solutions by electro-peroxone process

Electro-peroxone (E-peroxone) is a novel electrocatalytic ozonation process that combines ozonation and electrolysis process to enhance pollutant degradation during water and wastewater treatment. This enhancement has been mainly attributed to several mechanisms that increase O3 transformation to ·OH in the E-peroxone system, e.g., electro-generation of H2O2 from O2 at a carbon-based cathode and its subsequent peroxone reaction with O3 to ·OH, electro-reduction of O3 to ·OH at the cathode, and O3 decomposition to ·OH at high local pH near the cathode. To get more insight how these mechanisms contribute respectively to the enhancement, this study investigated total organic carbon (TOC) elimination from oxalic acid (OA) solutions by the E-peroxone process. Results show that the E-peroxone process significantly increased TOC elimination rate by 10.2-12.5 times compared with the linear addition of the individual rates of corresponding ozonation and electrolysis process. Kinetic analyses reveal that the electrochemically-driven peroxone reaction is the most important mechanism for the enhanced TOC elimination rate, while the other mechanisms contribute minor to the enhancement by a factor of 1.6-2.5. The results indicate that proper selection of electrodes that can effectively produce H2O2 at the cathode is critical to maximize TOC elimination in the E-peroxone process.

Effect of penehyclidine hydrochloride on β-arrestin-1 expression in lipopolysaccharide-induced human pulmonary microvascular endothelial cells

β-arrestins are expressed proteins that were first described, and are well-known, as negative regulators of G protein-coupled receptor signaling. Penehyclidine hydrochloride (PHC) is a new anti-cholinergic drug that can inhibit biomembrane lipid peroxidation, and decrease cytokines and oxyradicals. However, to date, no reports on the effects of PHC on β-arrestin-1 in cells have been published. The aim of this study was to investigate the effect of PHC on β-arrestin-1 expression in lipopolysaccharide (LPS)-induced human pulmonary microvascular endothelial cells (HPMEC). Cultured HPMEC were pretreated with PHC, followed by LPS treatment. Muscarinic receptor mRNAs were assayed by real-time quantitative PCR. Cell viability was assayed by the methyl thiazolyl tetrazolium (MTT) conversion test. The dose and time effects of PHC on β-arrestin-1 expression in LPS-induced HPMEC were determined by Western blot analysis. Cell malondialdehyde (MDA) level and superoxide dismutase (SOD) activity were measured. It was found that the M3 receptor was the one most highly expressed, and was activated 5 min after LPS challenge. Furthermore, 2 μg/mL PHC significantly upregulated expression of β-arrestin-1 within 10 to 15 min. Compared with the control group, MDA levels in cells were remarkably increased and SOD activities were significantly decreased in LPS pretreated cells, while PHC markedly decreased MDA levels and increased SOD activities. We conclude that PHC attenuated ROS injury by upregulating β-arrestin-1 expression, thereby implicating a mechanism by which PHC may exert its protective effects against LPS-induced pulmonary microvascular endothelial cell injury.

Two-port laparoscopic cholecystectomy with modified suture retraction of the fundus: A practical approach

CONTEXT

Although transumbilical single incision laparoscopic cholecystectomy (SILC) has been demonstrated to be superior cosmetic, it is only limited to simple cases at present. In complex cases, the standard four- or three-port LC is still the treatment of choice.

AIM

To summarize the clinical effect of a modified technique in two-port LC.

SETTINGS AND DESIGN

A consecutive series of patients with benign gallbladder diseases admitted to the provincial teaching hospital who underwent LC in the past 4 years were included. A modified two-port LC was the first choice except for those requiring laparoscopic common bile duct exploration (LCBDE).

MATERIALS AND METHODS

The operation was done with suture retraction of the fundus by a needle-like retractor. The patients' data, including the operative time, time consumed by gallbladder retraction, operative bleeding, conversion rate, rate of adding trocars, and postoperative complications were recorded.

STATISTICAL ANALYSIS

Data were expressed as percentage and mean with standard deviation.

RESULTS

Total 107 patients with chronic calculous cholecystitis (N = 61), acute calculous cholecystitis (N = 43), and cholecystic polyps (N = 3) received two-port LC. The procedure was successful in 99 out of 107 cases (success rate, 92.5%), and a third trocar was added in the remaining 8 cases (7.5%) due to severe pathological changes. The operative time was 47.2 (±13.21) min. There was no conversion to open surgery.

CONCLUSION

Two-port LC using a needle-like retractor for suture retraction of the gallbladder fundus is a practical approach when considering the safety, convenience, and indications as well as relatively minimal invasion.

Nitrite reduces acute lung injury and improves survival in a rat lung transplantation model

Ischemia/reperfusion injury (IRI) is the most common cause of early mortality following lung transplantation (LTx). We hypothesized that nitrite, an endogenous source of nitric oxide (NO), may protect lung grafts from IRI. Rat lung grafts were stored in preservation solution at 4°C for 6 hours. Both grafts and recipients were treated with nitrite. Nitrite treatment was associated with significantly higher levels of tissue oxygenation, lower levels of cytokines and neutrophil/macrophage infiltration, lower myeloperoxidase activity, reduced oxidative injury and increased cGMP levels in grafts than in the controls. Treatment with either a nitric oxide scavenger or a soluble guanylyl cyclase (sGC) inhibitor diminished the beneficial effects of nitrite and decreased cGMP concentrations. These results suggest that nitric oxide, generated from nitrite, is the molecule responsible for the effects of nitrite via the nitric oxide/sGC/cGMP pathway. Allopurinol, a xanthine oxidoreductase (XOR) inhibitor, abrogated the protective effects of nitrite, suggesting that XOR is a key enzyme in the conversion of nitrite to nitric oxide. In vitro experiments demonstrated that nitrite prevented apoptosis in pulmonary endothelial cells. Nitrite also exhibits longer survival rate in recipients than control. In conclusion, nitrite inhibits lung IRI following cold preservation and had higher survival rate in LTx model.

Synovial fluid dynamics with small disc perforation in temporomandibular joint

The articular disc plays an important role as a stress absorber in joint movement, resulting in stress reduction and redistribution in the temporomandibular joint (TMJ). The flow of synovial fluid in the TMJ may follow a regular pattern during movement of the jaw. We hypothesised that the regular pattern is disrupted when the TMJ disc is perforated. By computed tomography arthrography, we studied the upper TMJ compartment in patients with small disc perforation during jaw opening-closing at positions from 0 to 3 cm. Finite element fluid dynamic modelling was accomplished to analyse the pattern of fluid flow and pressure distribution during the movements. The results showed that the fluid flow in the upper compartment generally formed an anticlockwise circulation but with local vortexes with the jaw opening up to 2 cm. However, when the jaw opening-closing reached 3 cm, an abnormal flow field and the fluid pressure change associated with the perforation may increase the risk of perforation expansion or rupture and is unfavourable for self-repair of the perforated disc.

A comparison of potency of and intracellular signaling events provoked by, small molecule and protein-based mpl agonists

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Background: Thrombopoietin (TPO) interacts with its receptor (mpl) to initiate signal transduction and increase platelet production. Other mpl agonists have been developed for clinical use: MDGF (a recombinant protein) and romiplostim (a peptibody) are protein-based mpl agonists; eltrombopag (a small molecule) is a nonpeptide mpl agonist. Methods: Mpl agonists were compared for their ability to induce cellular responses and activate relevant signaling pathways in mpl-expressing cells. Proliferation was assessed by ATP bioluminescence in Baf3/mpl cells treated with mpl agonists for 2 days. Differentiation was assessed by flow cytometric-detection of CD41 and CD61 expression on human CD34+ cells cultured with mpl agonists for 7 days. Activation of signaling pathways was determined by Western blot analysis of proteins from serum-starved Baf3/mpl cells treated with mpl agonists for 20 minutes. Experiments were repeated 3 or more times. Results: The TPO concentration that produced a half-maximal (EC50) proliferative response of Baf3/mpl cells was comparable with that of romiplostim (Table). In contrast, a 30-fold greater concentration of MGDF and a 2,000-fold greater concentration of small molecule were required to produce the same degree of proliferation. In addition, a 1,000,000-fold greater concentration of small molecule compared with romiplostim was required to produce an EC50 for differentiation of CD34+ cells. Mpl agonists activated identical signaling pathways in Baf3/mpl cells: a similar dose-response for phosphorylation of JAK2, Stat3, Stat5, Erk1/2, and AKT was observed at their respective EC10, EC50, and EC100 concentrations. Conclusions: In Baf3/mpl cells, the small molecule was between 1,000- and 1,000,000-fold less potent than protein-based mpl agonists when corrected for molecular mass differences. Small molecule and protein-based mpl agonists were indistinguishable when mpl intracellular signaling was compared at similarly effective concentrations. [Table: see text]

[Table: see text]

A comparison of the effect of total intravenous anaesthesia with propofol and remifentanil and inhalational anaesthesia with isoflurane on the release of pro- and anti-inflammatory cytokines in patients undergoing open cholecystectomy

The aim of the study was to investigate the effects of two anaesthetic techniques (total intravenous technique vs. inhalational technique) on changes in pro- and anti-inflammatory cytokine levels during open cholecystectomy. Forty ASA PS I-II patients undergoing open cholecystectomy were randomly assigned to two groups. Group R received total intravenous anaesthesia with propofol and remifentanil and group F received balanced inhalational anaesthesia with isoflurane. The plasma levels of tumour necrosis factor-alpha (TNF-alpha), interleukin IL-6 and interleukin IL-10 were measured during and after surgery. The pro-inflammatory cytokine levels (TNF-alpha and IL-6) and the anti-inflammatory cytokine (IL-10) showed a significant increase in their concentrations compared with pre-induction levels in both groups (P < 0.05). By the end of anaesthesia and surgery, TNF-alpha and IL-6 were significantly lower in group R than in group F (P < 0.05). At the end of anaesthesia and 12 hours postoperatively, IL-10 levels in group R were higher than in group F (P < 0.05). These findings suggest that total intravenous anaesthesia using propofol and remifentanil suppresses the inflammatory response caused by surgery to a greater extent than a balanced inhalation technique using isoflurane.

Clonal turnover of MACE-carrying peach-potato aphids (Myzus persicae (Sulzer), Homoptera: Aphididae) colonizing Scotland

Peach-potato aphids, Myzus persicae (Sulzer), collected in Scotland in the years 1995 and 2002-2004 were characterized using four microsatellite loci and three insecticide resistance mechanisms. From 868 samples, 14 multilocus genotypes were defined (designated clones A-N). Five of these (denoted A, B, H, M and N) carried modified acetylcholinesterase (MACE) resistance, the most recent resistance mechanism to have evolved in M. persicae. The current paper shows that the continued presence of MACE aphids is due to turnover, as clones A and B were replaced in field samples by clones H, M and N in later seasons. Thus, insecticide-resistant populations in Scotland can be attributed to multiple waves of rapid clone colonisations and not to the continued presence of stable resistant clones or mutation or sexual recombination in local populations. The MACE clones carried varying levels of the other insecticide resistance mechanisms, kdr and esterase. The presence of these mechanisms could alter the clones success in the field depending on insecticide spraying (positive selection) and resistance fitness costs (negative selection).