Ectopic expression of an Old Yellow Enzyme (OYE3) gene from Saccharomyces cerevisiae increases the tolerance and phytoremediation of 2-nitroaniline in rice

2-nitroaniline (2-NA) is an environmental pollutant and has been extensively used as intermediates in organic synthesis. The presence of 2-NA in the environment is not only harmful for aquatic life but also mutagenic for human beings. In this study, we constructed transgenic rice expressing an Old Yellow Enzyme gene, ScOYE3, from Saccharomyces cerevisiae. The ScOYE3 transgenic plants were comprehensively investigated for their biochemical responses to 2-NA treatment and their 2-NA phytoremediation capabilities. Our results showed that the rice seedlings exposed to 2-NA stress, showed growth inhibition and biomass reduction. However, the transgenic plants exhibited strong tolerance to 2-NA stress compared to wild-type plants. Ectopic expression of ScOYE3 could effectively protect transgenic plants against 2-NA damage, which resulted in less reactive oxygen species accumulation in transgenic plants than that in wild-type plants. Our phytoremediation assay revealed that transgenic plants could eliminate more 2-NA from the medium than wild-type plants. Moreover, omics analysis was performed in order to get a deeper insight into the mechanism of ScOYE3-mediated 2-NA transformation in rice. Altogether, the function of ScOYE3 during 2-NA detoxification was characterized for the first time, which serves as strong theoretical support for the phytoremediation potential of 2-NA by Old Yellow Enzyme genes.

Biosynthesis of melatonin from L-tryptophan by an engineered microbial cell factory

BACKGROUND

The demand for melatonin is increasing due to its health-promoting bioactivities such as antioxidant and sleep benefits. Although melatonin is present in various organisms, its low content and high extraction cost make it unsustainable. Biosynthesis is a promising alternative method for melatonin production. However, the ectopic production of melatonin in microorganisms is very difficult due to the low or insoluble expression of melatonin synthesis genes. Hence, we aim to explore the biosynthesis of melatonin using Escherichia coli as a cell factory and ways to simultaneously coordinated express genes from different melatonin synthesis pathways.

RESULTS

In this study, the mXcP4H gene from Xanthomonas campestris, as well as the HsAADC, HsAANAT and HIOMT genes from human melatonin synthesis pathway were optimized and introduced into E. coli via a multi-monocistronic vector. The obtained strain BL7992 successfully synthesized 1.13 mg/L melatonin by utilizing L-tryptophan (L-Trp) as a substrate in a shake flask. It was determined that the rate-limiting enzyme for melatonin synthesis is the arylalkylamine N-acetyltransferase, which is encoded by the HsAANAT gene. Targeted metabolomics analysis of L-Trp revealed that the majority of L-Trp flowed to the indole pathway in BL7992, and knockout of the tnaA gene may be beneficial for increasing melatonin production.

CONCLUSIONS

A metabolic engineering approach was adopted and melatonin was successfully synthesized from low-cost L-Trp in E. coli. This study provides a rapid and economical strategy for the synthesis of melatonin.

Three-dimensional bone remodelling of glenoid fossa in patients with skeletal Class III malocclusion after bimaxillary orthognathic surgery

This study aimed to characterize three-dimensional quantitative morphological changes of glenoid fossa in patients with skeletal Class III malocclusion treated with bimaxillary orthognathic surgery. Ninety-five eligible patients (50 male, 45 female; mean age 22.09 years) were enrolled retrospectively. Cone beam computed tomography obtained at 1 week preoperatively (T0), immediately after surgery (T1), and at ≥ 12 months postoperatively (T2) were registered based on cranial base using voxel-based registration in 3D Slicer. Glenoid fossa surface was divided spatially into four regions, and bone modelling in these regions was visualized with color maps. Our data revealed that the mean surface variations of glenoid fossa were small, with modest bone formation as a whole. No significant associations between anteroposterior or vertical mandibular displacement and overall glenoid fossa remodeling were found (P > 0.05). Moreover, bone deposition was frequently observed in the anterior-lateral region of glenoid fossa in patients with a larger mandibular movement during T0-T1 (P < 0.001). Paired bone formation in the anterior-lateral region of glenoid fossa and bone resorption in the anterior-lateral region of condylar head was frequently observed. Collectively, our results revealed that glenoid fossa underwent complex but modest bone remodeling after bimaxillary surgery in skeletal Class III patients.

Adverse birth outcomes related to concentrations of per- and polyfluoroalkyl substances (PFAS) in maternal blood collected from pregnant women in 1960-1966

BACKGROUND

Prior animal and epidemiological studies suggest that per- and polyfluoroalkyl substances (PFAS) exposure may be associated with reduced birth weight. However, results from prior studies evaluated a relatively small set of PFAS.

OBJECTIVES

Determine associations of gestational PFAS concentrations in maternal serum samples banked for 60 years with birth outcomes.

METHODS

We used data from 97 pregnant women from Boston and Providence that enrolled in the Collaborative Perinatal Project (CPP) study (1960-1966). We quantified concentrations of 27 PFAS in maternal serum in pregnancy and measured infant weight, height and ponderal index at birth. Covariate-adjusted associations between 11 PFAS concentrations (>75% detection limits) and birth outcomes were estimated using linear regression methods.

RESULTS

Median concentrations of PFOA, PFNA, PFHxS, and PFOS were 6.189, 0.330, 14.432, and 38.170 ng/mL, respectively. We found that elevated PFAS concentrations during pregnancy were significantly associated with lower birth weight and ponderal index at birth, but no significant associations were found with birth length. Specifically, infants born to women with PFAS concentrations ≥ median levels had significantly lower birth weight (PFOS: β = -0.323, P = 0.006; PFHxS: β = -0.292, P = 0.015; PFOA: β = -0.233, P = 0.03; PFHpS: β = -0.239, P = 0.023; PFNA: β = -0.239, P = 0.017). Similarly, women with PFAS concentrations ≥ median levels had significantly lower ponderal index (PFHxS: β = -0.168, P = 0.020; PFHxA: β = -0.148, P = 0.018).

CONCLUSIONS

Using data from this US-based cohort study, we found that 1) maternal PFAS levels from the 1960s exceeded values in contemporaneous populations and 2) that gestational concentrations of certain PFAS were associated with lower birth weight and infant ponderal index. Additional studies with larger sample size are needed to further examine the associations of gestational exposure to individual PFAS and their mixtures with adverse birth outcomes.

[Study on the distribution pattern of allergen sIgE in patients with respiratory allergic diseases in a hospital in Shanxi Province]

To explore the allergen sensitization status of patients with respiratory allergic diseases in Shanxi Province, and to provide a basis for the diagnosis, treatment and prevention of allergic diseases. It is a cross-sectional study, a total of 1 680 patients with allergic rhinitis and/or asthma diagnosed at the Department of Allergic Reaction of Shanxi Bethune Hospital from July 2021 to June 2023 who underwent allergen sIgE testing and/or skin prick test were retrospectively enrolled.There were 772 males and 908 females.The age range was 3 to 88 years. The median age was 35 years.There were 108 cases in the child group (≤12 years old), 102 cases in the adolescent group (13-17 years old), 819 cases in the youth group (18-40 years old), 498 cases in the middle-aged group (41-65 years old), and 153 cases in the elderly group (>65 years old). There were 333 cases in the allergic rhinitis group, 827 cases in the allergic asthma group, and 520 cases in the allergic rhinitis with asthma group. There were 1 254 urban patients and 426 rural patients.There were 253 cases in the northern Shanxi region, 1 195 cases in the central Shanxi region, and 232 cases in the southern Shanxi region. Statistical analyses were performed using the χ 2 test or Fisher's exact probability method to compare the differences in allergen sIgE positivity rates by sex, age, disease, living environment, and geography. The results showed that 1 027 patients (61.1%) were positive for at least one allergen sIgE, with Artemisia having the highest rate of positivity (603/1 680, 35.9%), followed by ragweed (302/1 680, 18.0%) and dust mite combinations (245/1 680, 14.6%). The number of individuals with single-allergen sIgE positivity was 357 (357/1 027, 34.8%), with the highest number of single-allergen sIgE positive results associated with Artemisia (114/357, 31.9%). The number of multiple-allergen sIgE positive results was 670 cases (670/1 027, 65.2%), with the highest number of patients having 2 allergen sIgE positive results (243/670, 36.3%). The overall positivity rate for allergen sIgE was significantly higher among males than among females (65.7% vs. 57.3%, χ2=12.405, P<0.001). Overall positivity for inhalant allergen sIgE was higher in the child and adolescent groups (88.0% vs. 88.2% vs. 59.8% vs. 40.2% vs. 19.0%, χ2=223.372, P<0.001), and food allergen sIgE positivity was highest in the child group (54.6% vs. 36.3% vs. 26.0% vs. 18.9% vs. 21.6%,χ2=66.383,P<0.001). The sIgE positivity rate of inhalant allergens was significantly higher in the allergic rhinitis group and the allergic rhinitis with asthma group than in the allergic asthma group, except for cockroaches and molds (P<0.05). The overall positive rate of allergen sIgE was significantly higher among urban patients than among rural patients (66.2% vs. 46.2%, χ2=53.230, P<0.001). The difference in the overall positive rate of allergen sIgE among patients from different regions was not statistically significant (56.1% vs. 62.0% vs. 62.1%, χ2=3.140, P=0.208). The sIgE positivity of dust mite combinations was significantly higher in the central Shanxi region and the southern Shanxi region than in the northern Shanxi region (15.5% vs. 18.1% vs. 7.1%,χ2=14.411, P=0.001). In conclusion, artemisia was the most important sensitizer for respiratory allergic diseases in Shanxi Province. The types of allergens and positivity rates were different for different sexes, ages, diseases, living environments, and regions. Therefore, patients with allergic diseases should be tested for allergens to help with the diagnosis, treatment and prevention of allergic diseases.

Residual Strain Evolution Induced by Crystallization Kinetics During Anti-Solvent Spin Coating in Organic-Inorganic Hybrid Perovskite

Organic-inorganic hybrid perovskite (OIHP) polycrystalline thin films are attractive due to their outstanding photoelectronic properties. The anti-solvent spin coating method is the most widely used to synthesize these thin films, and the residual strain is inevitably originates and evolves during the process. However, this residual strain evolution induced by crystallization kinetics is still poorly understood. In this work, the in situ and ex situ synchrotron grazing-incidence wide-angle X-ray scattering (GIWAXS) are utilized to characterize the evolution and distribution of the residual strain in the OIHP polycrystalline thin film during the anti-solvent spin coating process. A mechanical model is established and the mechanism of the crystallization kinetics-induced residual strain evolution process is discussed. This work reveals a comprehensive understanding of the residual strain evolution during the anti-solvent spin coating process in the OIHP polycrystalline thin films and provides important guidelines for the residual strain-related strain engineering, morphology control, and performance enhancement.

Metabolic engineering for the biosynthesis of bis-indolylquinone terrequinone A in Escherichia coli from L-tryptophan and prenol

BACKGROUND

Terrequinone A is a bis-indolylquinone natural product with antitumor activity. Due to its unique asymmetric quinone core structure and multiple functional groups, biosynthesis is more efficient and environmentally friendly than traditional chemical synthesis. Currently, most bis-indolylquinones are obtained by direct extraction from fungi or by chemical synthesis. By focusing on the biosynthesis of terrequinone A, we hope to explore the way to synthesize bis-indolylquinones de novo using Escherichia coli as a cell factory.

RESULTS

In this study, a terrequinone A synthesis pathway containing the tdiA-tdiE genes was constructed into Escherichia coli and activated by a phosphopantetheinyl transferase gene sfp, enabling the strain to synthesize 1.54 mg/L of terrequinone A. Subsequently, a two-step isopentenol utilization pathway was introduced to enhance the supply of endogenous dimethylallyl diphosphate (DMAPP) in E. coli, increasing the level of terrequinone A to 20.1 mg/L. By adjusting the L-tryptophan (L-Trp)/prenol ratio, the major product could be changed from ochrindole D to terrequinone A, and the content of terrequinone A reached the highest 106.3 mg/L under the optimized culture conditions. Metabolic analysis of L-Trp indicated that the conversion of large amounts of L-Trp to indole was an important factor preventing the further improvement of terrequinone A yield.

CONCLUSIONS

A comprehensive approach was adopted and terrequinone A was successfully synthesized from low-cost L-Trp and prenol in E. coli. This study provides a metabolic engineering strategy for the efficient synthesis of terrequinone A and other similar bis-indolylquinones with asymmetric quinone cores. In addition, this is the first report on the de novo biosyhthesis of terrequinone A in an engineered strain.

Polymer-based graphene composite molding: a review

Polymer-based graphene composite products with high mechanical properties, heat resistance, corrosion resistance and electrical conductivity are obtained by different molding technologies. Although these processes conveniently realize the molding of polymer composites, it is often difficult to control the product quality because of the fluctuation of the temperature and pressure threshold. At the same time, a high temperature or external load will carbonize polymer composites or cause excessive porosity to influence the compacted density and electrical conductivity. In this review, additive manufacturing, injection molding, extrusion molding, hot pressing, spark plasma sintering, electromagnetic-assisted molding and other processing methods were introduced. Meanwhile, the powder molding mechanism and material constitutive model were introduced, providing appropriate molding methods and theoretical guidance based on the performance of raw materials and the performance requirements of products.

ElNFS1, a nitroreductase gene from Enterobacter ludwigii, confers enhanced detoxification and phytoremediation of 4-nitrobenzaldehyde in rice

4-nitrobenzaldehyde (4-NBA) is a widely used chemical intermediate for industrial application and an important photodegradation product of chloramphenicol. This compound represents a substantial threat to human health and ecosystem due to its genotoxic and mutagenic effect. In this study, the 4-NBA detoxification by transgenic rice overexpressing a bacterial nitroreductase gene, ElNFS1, from Enterobacter ludwigii were investigated. The cytosol-targeted ElNFS1 transgenic plants were selected to comprehensively examine their physio-biochemical responses and phytoremediation potential to 4-NBA. Our results showed that the transgenic plants exhibited strong tolerance to 4-NBA. Overexpression of ElNFS1 could significantly alleviate 4-NBA-induced damages of photosynthetic apparatus and reactive oxygen species overproduction in transgenic plants. The phytoremediation assay revealed that transgenic plants could remove more 4-NBA from the medium than wild-type plants. HPLC and LC-MS assays showed that 4-aminobenzaldehyde was found in the reductive products of 4-NBA. Altogether, the function of ElNFS1 during 4-NBA detoxification was characterized for the first time, which provides a strong theoretical support for the application potential of ElNFS1 transgenic plants on the phytoremediation of 4-NBA.

[Impact of different obesity patterns on coronary microvascular function in male patients with non-obstructive coronary artery disease]

Objective: This study sought to investigate the impact of different obesity patterns on coronary microvascular function in male patients with non-obstructive coronary artery disease. Methods: We retrospectively analyzed clinical data of male patients diagnosed with suspected coronary microvascular dysfunction (CMD) in the First Hospital of Shanxi Medical University between December 2015 and August 2021. All patients underwent the one-day rest and stress ¹³N-ammonia positron emission tomography myocardial perfusion imaging. Overall obesity was defined by body mass index (BMI) ≥28 kg/m² and abdominal obesity was defined by waist circumference ≥90 cm. Hyperemic myocardial blood flow (MBF)<2.3 ml·min^-1·g^-1 or coronary flow reserve (CFR)<2.5 were referred as CMD. All patients were grouped based on their BMI and waist circumference. MBF, CFR, the incidence of CMD, hemodynamic parameters, and cardiac function were compared among the groups. Results: A total of 136 patients were included. According to BMI and waist circumference, patients were categorized into 3 groups: control group (n=45), simple abdominal obesity group (n=53) and compound obesity group (n=38). Resting MBF did not differ between groups (F=0.02,P=0.994). Compared with the control group, hyperemic MBF was significantly lower in the simple abdominal obesity and compound obesity groups ((2.82±0.64) ml·min^-1·g^-1, (2.44±0.85) ml·min^-1·g^-1 and (2.49±0.71) ml·min^-1·g^-1, both P<0.05, respectively). Hyperemic MBF was comparable among the groups of patients with obesity (P=0.772). CFR was significantly lower in the simle abdominal obesity group compared with the control group (2.87±0.99 vs. 3.32±0.62,P=0.012). Compared with the control group, CFR tended to be lower in the compound obesity group (3.02±0.91 vs. 3.32±0.62,P=0.117). The incidence of CMD was significantly higher in both the simple abdominal obesity and compound obesity groups than in the control group (62.3%, 52.6% vs. 22.2%, both P<0.01, respectively). Waist circumference was an independent risk factor for male CMD (OR=1.057, 95%CI: 1.013-1.103, P=0.011). Conclusions: In male patients with non-obstructive coronary artery disease, abdominal obesity is associated with decreased coronary microvascular function. Male patients with simple abdominal obesity face the highest risk of CMD.

Strong band renormalization and emergent ferromagnetism induced by electron-antiferromagnetic-magnon coupling

The interactions between electrons and antiferromagnetic magnons (AFMMs) are important for a large class of correlated materials. For example, they are the most plausible pairing glues in high-temperature superconductors, such as cuprates and iron-based superconductors. However, unlike electron-phonon interactions (EPIs), clear-cut observations regarding how electron-AFMM interactions (EAIs) affect the band structure are still lacking. Consequently, critical information on the EAIs, such as its strength and doping dependence, remains elusive. Here we directly observe that EAIs induce a kink structure in the band dispersion of Ba_1-xK_xMn₂As₂, and subsequently unveil several key characteristics of EAIs. We found that the coupling constant of EAIs can be as large as 5.4, and it shows strong doping dependence and temperature dependence, all in stark contrast to the behaviors of EPIs. The colossal renormalization of electron bands by EAIs enhances the density of states at Fermi energy, which is likely driving the emergent ferromagnetic state in Ba_1-xK_xMn₂As₂ through a Stoner-like mechanism with mixed itinerant-local character. Our results expand the current knowledge of EAIs, which may facilitate the further understanding of many correlated materials where EAIs play a critical role.

[Clinicopathological characteristics related to Miller/Payne grading system of breast carcinoma after neoadjuvant therapy and establishment of novel prediction models]

Objective: To investigate the correlation between clinicopathological features and Miller/Payne (MP) grading system of breast carcinoma after neoadjuvant treatment and to establish novel prediction models. Methods: A total of 1 053 cases of invasive breast carcinoma NOS that undertaken neoadjuvant treatment according to Guidelines of CSCO for Breast Cancer were selected at the Key Laboratory of Carcinogenesis and Translational Research, Peking University Cancer Hospital & Institute from September 2016 to September 2019, and the clinical, pathologic data, MP grading and immunohistochemical staining were evaluated. Statistical analysis was conducted using R software. Several novel computer models on prediction of MP grading were established and validated. Results: Among 1 053 patients who accepted neoadjuvant treatment, 316 patients (316/1 053, 30%) were evaluated as MP5 postoperatively, and 737 patients (737/1 053, 70%) did not meet MP5 level. MP5 had significant association with histological grade, ER and PR expression, HER2 status, Ki-67 index and molecular classification (P<0.05). Univariate/multivariate logistic regression analyses further showed that the above clinicopathological features were also independent influencing factors of MP5 grade; five-fold cross-validation was used to evaluate the performance of the models, and the sensitivity and specificity of different models were obtained. Conclusions: MP grading of invasive breast carcinoma NOS after neoadjuvant treatment is associated with high histological grade, negative ER and PR expression, HER2 positivity, high Ki-67 index and molecular classification, which are independent influence factors. GBM model recommended through comparison can provide some help for clinical diagnosis and treatment.

[Effect of exosome derived from ovarian cancer cell on the differentiation of fibroblast]

Objective: To study the effects of exosome secreted by ovarian cancer (OC) cell on the differentiation and metastasis of normal fibroblasts (NFs). Methods: NFs were collected from patients who underwent hysteromyoma resection in the Affiliated Hospital of Qingdao University from May to December 2019. Exosome was extracted from the culture supernatant of SKOV3 cells by using ultra-high-speed centrifugation. The NFs were co-cultured with condition medium (CM), exosome of SKOV3 (SKOV3-exo) and control medium. The expression levels of fibroblast activation protein (FAP) and α-smooth muscle actin (α-SMA) were detected by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot. The metastatic ability of NFs was detected by Transwell array. Results: Under the transmission electron microscope, the extracellular vesicles extracted from the culture supernatant of SKOV3 were 30-100 nm in diameter with cup holder-like bilayer membrane structure, and the protein expression levels of TSG101 and HSP27 in exosomes (1.00±0.05 and 1.12±0.13) were higher than those of ovarian cancer SKOV3 cells (0.22±0.21 and 0.36±0.14, respectively, P<0.05). PKH67 fluorescently labeled exosomes could be taken up by NFs. The expression levels of α-SMA and FAP mRNA in CM group(2.91±0.15 and 3.21±0.33)and SKOV3-exo group (3.50±0.21 and 4.63±0.24, respectively) were higher than that in blank group (1.00±0.06 and 1.00±0.13, P<0.05). The protein expression levels of α-SMA and FAP in CM group and SKOV3-exo group (0.89±0.11 and 1.25±0.09, 0.81±0.09 and 1.20±0.12) were higher than those in the blank group (0.12±0.31 and 0.11±0.19, respectively, P<0.05). The migrated numbers of cells in the CM group and SKOV3-exo group [(215.01±14.80) and (389.72±19.43), respectively] were higher than that in the blank group [(113.73±4.70), P<0.05]. Conclusion: The exosome secreted by SKOV3 cells can be taken up by NFs, which makes it to differentiate into cancer associated fibroblasts (CAFs) and significantly enhances its metastatic ability, indicating that OC cells may promote the transformation of normal ovarian mesenchymal fibroblasts to CAFs through exosome pathways, and then promote the development of ovarian cancer.

Rice carotenoid biofortification and yield improvement conferred by endosperm-specific overexpression of OsGLK1

Carotenoids, indispensable isoprenoid phytonutrients, are synthesized in plastids and are known to be deficient in rice endosperm. Many studies, involving transgenic manipulations of carotenoid biosynthetic genes, have been performed to obtain carotenoid-enriched rice grains. Nuclear-encoded GOLDEN2-LIKE (GLK) transcription factors play important roles in the regulation of plastid and thylakoid grana development. Here, we show that endosperm-specific overexpression of rice GLK1 gene (OsGLK1) leads to enhanced carotenoid production, increased grain yield, but deteriorated grain quality in rice. Subsequently, we performed the bioengineering of carotenoids biosynthesis in rice endosperm by introducing other three carotenogenic genes, tHMG1, ZmPSY1, and PaCrtI, which encode the enzymes truncated 3-hydroxy-3-methylglutaryl-CoA reductase, phytoene synthase, and phytoene desaturase, respectively. Transgenic overexpression of all four genes (OsGLK1, tHMG1, ZmPSY1, and PaCrtI) driven by rice endosperm-specific promoter GluB-1 established a mini carotenoid biosynthetic pathway in the endosperm and exerted a roughly multiplicative effect on the carotenoid accumulation as compared with the overexpression of only three genes (tHMG1, ZmPSY1, and PaCrtI). In addition, the yield enhancement and quality reduction traits were also present in the transgenic rice overexpressing the selected four genes. Our results revealed that OsGLK1 confers favorable characters in rice endosperm and could help to refine strategies for the carotenoid and other plastid-synthesized micronutrient fortification in bioengineered plants.

Metabolic engineering of Escherichia coli for efficient degradation of 4-fluorophenol

As a kind of refractory organic pollutant, 4-fluorophenol (4-FP) can be degraded by only a few microorganisms with low efficiency because of the great electron-withdrawing ability of fluorine atoms. So it is necessary to artificially construct engineered strain to improve the degradation efficiency and meet the requirements of pollutant degradation. In this study, four genes (fpdA2, fpdB, fpdC, and fpdD) for 4-FP degradation from Arthrobacter sp. strain IF1 were optimized and synthesized and then reconstructed into Escherichia coli by a multi-monocistronic vector to obtain recombinant BL-fpd that could degrade 4-FP efficiently. Under optimized induction conditions (inducing the strain by 2 g/L L-arabinose and 1 mM IPTG at 37 ℃), BL-fpd could completely degrade 2 mM 4-FP, 4-chlorophenol, 4-bromophenol, and 4-nitrophenol into β-ketoadipate, which could be further metabolized by the bacteria. FpdA2 showed the highest activity towards 4-bromophenol. The strain could completely degrade 1 mM 4-FP in industrial wastewater within 3 h. This study provided a promising strain for the degradation of 4-FP and some other 4-substituted phenols. The construction technologies of multi-monocistronic expression vector may also be used to construct other organic pollutants degrading bacteria.

Enhanced phytoremediation of selenium using genetically engineered rice plants

Selenium (Se) is a micronutrient essential for human and animal health. However, Se is toxic at high levels because the nonspecific substitution of cysteine by selenocysteine could lead to protein malfunction. In an attempt to prevent nonspecific selenocysteine incorporation into proteins, we simultaneously overexpressed the gene encoding selenocysteine lyase from Homo sapiens (HsSL), which specifically catalyzes the decomposition of selenocysteine into elemental Se⁰ and alanine, and the gene encoding selenocysteine methyltransferase from Astragalus bisulcatus (AbSMT), which methylates selenocysteine into methylselenocysteine in rice. The transgenic plants showed normal growth under standard conditions. Se treatment resulted in higher levels of alanine and methylselenocysteine in transgenic plants than in wild-type plants, which indicated that this approach might have successfully redirected Se flow in the plant. Overexpression of HsSL and AbSMT in rice also endows transgenic plants with hyposensitivity to Se stress at the seed germination stage. The transgenic plants showed enhanced selenate and selenite tolerance, which was simultaneously supported by fresh weight values. Moreover, our phytoremediation assay revealed that the transgenic plants exhibited greatly improved Se elimination capabilities and accumulated about 38.5% and 128.6% more Se than wild-type plants when treated with selenate and selenite, respectively. This study offers hope that genetically modified plants could play a role in the restoration of Se-contaminated environment.

[Systematic evaluation of qualitative research on the real experience of burn patients during rehabilitation]

Objective: To systematically evaluate and integrate the real experience of burn patients during rehabilitation, and to provide theoretical guidance for the continual nursing care for burn patients. Methods: The systematic evaluation method was adopted. Databases including the China National Knowledge Internet, Wanfang Database, China Biology Medicine disc were retrieved with the search terms in Chinese version of "/, //, ////", and PubMed, Embase, CINAHL, PsycINFO, Cochrane Library were retrieved with the search terms of "burn/burns, rehabilitation/recovery/survivor/survive, experience/views/perceptions/, qualitative/phenomenon/interview/grounded theory". The qualitative studies on the real experience of burn patients during rehabilitation published from the establishment of each database to June 2020 were searched. The quality of the included studies was evaluated according to the quality evaluation criteria for qualitative research of the Joanna Briggs Institute Evidence-Based Health Care Center. The research country, research method, research object, research content, and main research result were summarized, and meta-synthesis of the research results was conducted with the aggregative integration method. Results: A total of 12 studies were included, and the quality of all the studies was grade B. The studies were conducted in 8 countries including Australia, Canada, Norway, etc., the research method mainly was phenomenological research method, and all the studies were focused on adult burn patients. A total of 46 specific themes were extracted with totally 10 new categories formed after summarization, and 3 integrated results were obtained as follows: burn patients suffered from both physical and psychological burdens, and their normal life was broken; burn patients gained post-traumatic growth and could actively adjust to cope with life difficulties; burn patients had multiple needs. Conclusions: Burn patients experience both physical and psychological pains during rehabilitation, so they long for multiple support from family and society. Medical staff, social groups, and family members should pay attention to the psychological experience and needs of burn patients with different characteristics during rehabilitation, and build a multi-directional social support system to help patients return to the society and rebuild their lives.

Optimization and reconstruction of two new complete degradation pathways for 3-chlorocatechol and 4-chlorocatechol in Escherichia coli

Chlorinated aromatic compounds are a serious environmental concern because of their widespread occurrence throughout the environment. Although several microorganisms have evolved to gain the ability to degrade chlorinated aromatic compounds and use them as carbon sources, they still cannot meet the diverse needs of pollution remediation. In this study, the degradation pathways for 3-chlorocatechol (3CC) and 4-chlorocatechol (4CC) were successfully reconstructed by the optimization, synthesis, and assembly of functional genes from different strains. The addition of a ¹³C-labeled substrate and functional analysis of different metabolic modules confirmed that the genetically engineered strains can metabolize chlorocatechol similar to naturally degrading strains. The strain containing either of these artificial pathways can degrade catechol, 3CC, and 4CC completely, although differences in the degradation efficiency may be noted. Proteomic analysis and scanning electron microscopy observation showed that 3CC and 4CC have toxic effects on Escherichia coli, but the engineered bacteria can significantly eliminate these inhibitory effects. As core metabolic pathways for the degradation of chloroaromatics, the two chlorocatechol degradation pathways constructed in this study can be used to construct pollution remediation-engineered bacteria, and the related technologies may be applied to construct complete degradation pathways for complex organic hazardous materials.

What is an appropriate caesarean delivery rate for China: a multicentre survey

Objective

To assess the current status of caesarean delivery (CD) in China, propose reference CD rates for China overall, and by regions, investigate the main indications for CDs and identify possible areas for safe reduction.

Design

A multicentre cross‐sectional study.

Setting

A total of 94 hospitals across 23 provinces in China.

Population

A total of 73 977 randomly selected deliveries.

Methods

We used a modified Robson classification to characterise CDs in subgroups and by regions, and the World Health Organization (WHO) C‐Model to calculate reference CD rates.

Main outcome measures

CD rates in China.

Results

In 2015–2016, the overall CD rate in China was 38.9% (95% CI 38.6–39.3%). Considering the obstetric characteristics of the population, the multivariable model‐based reference CD rate was estimated at 28.5% (95% CI 28.3–28.8%). Accordingly, an absolute reduction of 10.4% (or 26.7% relative reduction) may be considered. The CD rate varied substantially by region. Previous CD was the most common indication in all regions, accounting for 38.2% of all CDs, followed by maternal request (9.8%), labour dystocia (8.3%), fetal distress (7.7%) and malpresentation (7.6%). Overall, 12.7% of women had prelabour CDs, contributing to 32.8% of the total CDs.

Conclusions

Nearly 39% of births were delivered by caesarean in China but a reduction of this rate by a quarter may be considered attainable. Repeat CD contributed more than one‐third of the total CDs. Given the large variation in maternal characteristics, region‐specific or even hospital‐specific reference CD rates are needed for precision management of CD.

Tweetable abstract

The caesarean rate in 2015–2016 in China was 38.9%, whereas the reference rate was 28.5%.

The caesarean rate in 2015–2016 in China was 38.9%, whereas the reference rate was 28.5%.

Linked article This article is commented on by M Varner, p. 148 in this issue. To view this mini commentary visit https://doi.org/10.1111/1471-0528.16953.

SlMYB14 promotes flavonoids accumulation and confers higher tolerance to 2,4,6-trichlorophenol in tomato

Flavonoids are small molecular secondary metabolites, which have a variety of biological functions. Transcriptional regulations of key enzyme genes play critical roles in the flavonoid biosynthesis. In this study, an R2R3-MYB transcription factor gene, SlMYB14, was isolated from tomato and characterized. The nucleus-localized SlMYB14 functions as a transcriptional activator in yeast. The expression of SlMYB14 could be induced by methyl jasmonic acid, wounding and ABA. SlMYB14 works downstream of SlMYC2 in the jasmonate signaling pathway. Overexpression of SlMYB14 under the control of CaMV35S promoter in tomato led to increased accumulation of flavonoids. RNA-sequencing analysis revealed that the transcript levels of several structural genes associated with flavonoid biosynthesis were up-regulated in transgenic tomato plants. Gel-shift assays confirmed that SlMYB14 protein could bind to the promoter regions of SlPAL genes. It was also found that overexpression of SlMYB14 improved the tolerance of transgenic plants to 2,4,6-trichlorophenol (2,4,6-TCP), an environmental organic pollutant which could cause serious oxidative damage to plant. These results suggest that SlMYB14 participates in the regulation of flavonoid biosynthesis and might play a role in maintaining reactive oxygen species homeostasis in plant. SlMYB14 gene also has the potential to contribute to the phytoremediation of 2,4,6-TCP-contaminated soils.

Microbiome changes associated with acute and chronic pancreatitis: A systematic review

BACKGROUND

Altered intestinal microbiota has been reported in pancreatic disorders, however, it remains unclear whether these changes alter the course of disease in patients with acute (AP) and chronic pancreatitis (CP), or whether these disease states alter the environment to enable pathogenic microbial composition changes to occur. We undertook a systematic review to characterize the gut microbiome in pancreatitis patients.

METHODS

MEDLINE and EMBASE were searched for studies on microbiota in pancreatitis published from January 1, 2000 to June 5, 2020. Animal studies, reviews, case reports, and non-English articles were excluded. A frequency analysis was performed for outcomes reported in ≥2 studies and studies were analyzed for risk of bias and quality of evidence.

RESULTS

22 papers met inclusion criteria; 15 included AP, 7 included CP. No studies were appropriately designed to assess whether alterations in the gut microbiome exacerbate pancreatitis or develop as a result of pancreatitis. We did identify several patterns of microbiome changes that are associated with pancreatitis. The gut microbiome demonstrated decreased alpha diversity in 3/3 A P studies and 3/3 C P studies. Beta diversity analysis revealed differences in bacterial community composition in the gut microbiome in 2/2 A P studies and 3/3 C P studies. Functionally, gut microbiome changes were associated with infectious pathways in AP and CP. Several studies suffered from high risk of bias and inadequate quality.

CONCLUSIONS

Detecting differences in microbial composition associated with AP and CP may represent a diagnostic tool. Appropriately controlled longitudinal studies are needed to determine whether microbiome changes are causative or reactive in pancreatitis.

Efficacy of utidelone plus capecitabine versus capecitabine for heavily pretreated, anthracycline- and taxane-refractory metastatic breast cancer: final analysis of overall survival in a phase III randomised controlled trial

BACKGROUND

Primary analysis of the phase III trial BG01-1323L demonstrated that utidelone plus capecitabine significantly improved progression-free survival (PFS) and overall response rate (ORR) versus capecitabine alone in heavily-pretreated patients with metastatic breast cancer (MBC). Here, we report the final overall survival (OS) analysis and updates of other endpoints.

PATIENTS AND METHODS

In total, 405 patients were randomised 2:1 to receive utidelone (30 mg/m² IV daily, days 1-5, over 90 min) plus capecitabine (1000 mg/m² orally b.i.d., days 1-14) or capecitabine alone (1250 mg/m² orally b.i.d., days 1-14) every 21 days. The secondary endpoint, OS, was estimated using the Kaplan-Meier product-limit approach at a two-sided alpha level of 0.05 after the prespecified 310 death events had been reached. Exploratory analyses of the primary endpoint, PFS, and the secondary endpoint, ORR, were also done. Safety was analysed in patients who had at least one dose of study drug.

RESULTS

At the final OS analysis, the median duration of follow-up was 19.6 months in the utidelone plus capecitabine group and 15.4 months in the capecitabine alone group. In the intention-to-treat population, 313 deaths had occurred at data cut-off, 203 of 270 patients in the combination group and 110 of 135 in the monotherapy group. Median OS in the combination group was 19.8 months compared with 16.0 months in the monotherapy group [hazard ratio (HR) = 0.75, 95% confidence intervals (CI) 0.59-0.94, P = 0.0142]. The updated analysis of PFS and ORR showed that the combination therapy remained superior to monotherapy. Safety results were similar to those previously reported with respect to incidence, severity and specificity. No late-emerging toxicities or new safety concerns occurred.

CONCLUSIONS

For heavily-pretreated, anthracycline- and taxane-resistant MBC patients, utidelone plus capecitabine significantly improved OS versus capecitabine alone. These results support the use of utidelone plus capecitabine as a novel therapeutic regimen for patients with MBC.

[Epidemiology of syphilis in Zhejiang province, 2010-2019]

Objective: To investigate the epidemiological characteristics of syphilis in Zhejiang province and to provide scientific basis for the development of syphilis prevention and control strategies. Methods: A descriptive epidemiological analysis was conducted on the incidence data of syphilis in Zhejiang from 2010 to 2019. Results: During the period, the incidence rate of syphilis decreased from 94.90/100 000 in 2010 to 53.53/100 000 in 2019 with an average decreasing rate of 6.16%. The annual decreases of the incidences of congenital syphilis, primary syphilis and secondary syphilis were all obvious, which were 43.47%, 21.38% and 14.19% respectively. The proportion of latent syphilis cases increased with year. Except for Lishui, the incidences of syphilis in the remaining 10 prefectures showed declining trends. The incidence rates in both men and women showed declining trends with the average rates of 4.80% and 6.45% respectively. The incidence peaks occurred in old men aged ≥60 years and in sexually active women aged 20-34 years, and the syphilis cases in age group ≥60 years increased significantly. The cases were mainly farmers, accounting for 43.00%. Conclusion: The incidence of syphilis in Zhejiang showed a decreasing trend, but the situation remains serious, indicating that the intensity and quality of the comprehensive prevention and control needs to be further strengthened.

Display of quintuple glucagon-like peptide 1 (28-36) nonapeptide on Bacillus subtilis spore for oral administration in the treatment of type 2 diabetes

AIMS

To develop an oral delivery system of glucagon-like peptide 1 (GLP-1) (28-36) for treating type-2 diabetes, B.S-GLP-1(28-36), a recombinant Bacillus subtilis spores transformed with a plasmid vector encoding five consecutive GLP-1 (28-36) nonapeptides with an enterokinase site was constructed.

METHODS AND RESULTS

GLP-1(28-36) nonapeptide was successfully expressed on the surface of B. subtilis spores and validated by Western blot and immunofluorescence. The therapeutic effect of oral administration of B.S-GLP-1(28-36) spores was evaluated in type 2 diabetic model mice. The efficacy of recombinant spores was examined for a period of 13 weeks after oral administration in diabetic mice. At the end of the sixth week, diabetic mice with oral administration of BS-GLP-1(28-36) spores showed decreased blood glucose levels from 2·4 × 10^{- 2}  mol l^-1 to 1·7 × 10^{- 2}  mol l^-1 . By the ninth week, the mean fasting blood glucose level in the experimental group was significantly lower than that in the control group 30 min after injection of pyruvate. At the end of the 10th week of oral administration, the blood glucose of the experimental group was significantly lower than that of the control group after intraperitoneal injection of glucose. By the 12th week, fasting blood glucose level and fasting insulin level were measured in all mice, the results showed that the recombinant spores increased the insulin sensitivity of mice.

CONCLUSIONS

The results of pathological observation showed that the recombinant spores also had a certain protective effect on the liver and islets of mice, and the content of GLP-1(28-36) in the pancreas of the experimental group was increased.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results of this study revealed that GLP-1(28-36) nonapeptides can reduce blood glucose and play an important role in the treatment of type 2 diabetes.

ADMA mediates gastric cancer cell migration and invasion via Wnt/β-catenin signaling pathway

Objective

To explore the role of ADMA in gastric cancer.

Methods

The specimens of 115 gastric cancer patients were analyzed by ELISA and survival analysis. Functional assays were used to assess the effects of ADMA on gastric cancer cells. Experiments were conducted to detect the signaling pathway induced by ADMA in GC.

Results

Gastric cancer patients with high ADMA levels had poor prognosis and low survival rate. Furthermore, high level of ADMA did not affect the proliferation while promoted the migration and invasion of gastric cancer cell. Moreover, ADMA enhanced the epithelial–mesenchymal transition (EMT). Importantly, ADMA positively regulated β-catenin expression in GC and promoted GC migration and invasion via Wnt/β-catenin pathway.

Conclusions

ADMA regulates gastric cancer cell migration and invasion via Wnt/β-catenin signaling pathway and which may be applied to clinical practice as a diagnostic and prognostic biomarker.

Electronic supplementary material

The online version of this article (10.1007/s12094-020-02422-7) contains supplementary material, which is available to authorized users.

AB1069 CONSIDERATION OF YAO SYNDROME AS A DIFFERENTIAL DIAGNOSIS FOR HEREDITARY PERIODIC FEVER SYNDROMES

Background:

Yao syndrome (YAOS, OMIM 617321), formerly termed nucleotide-binding oligomerization domain 2(NOD2)-associated autoinflammatory disease, is characterized by periodic fever, dermatitis, arthritis, and swelling of the distal extremities, as well as gastrointestinal and sicca-like symptoms. This disorder shares similar clinical phenotypes with hereditary periodic fever syndromes (HPFS) and thus can mimic one another.

Objectives:

This study aimed to exemplify by a comparison of YAOS vs familial Mediterranean fever (FMF).

Methods:

In this retrospective study, electronic medical records of a series of patients with YAOS were analyzed. All patients underwent genetic testing for periodic fever syndrome 6-gene panel (MEFV, TNFRSF1A, NLRP3, MVK, NLRP12 and NOD2).

Results:

All patients were Caucasian and had recurrent fever, patchy erythema, arthralgia, and gastrointestinal symptoms (Table 1). With negative DNA sequencing for MEFV, these patients were treated with colchicine for presumed FMF, with a good response in patient 2 and minimal or transient response in other two patients. Further genetic testing identified the NOD2 variants. Unlike HPFS, YAOS is generally sporadic and is mostly reported in adults; spongiotic dermatitis is common; YAOS is associated with the NOD2 variants, IVS8 + 158 in nearly all patients, IVS8 + 158/R702W in up to 30%, and IVS8 + 158/1007fs, G908R or other rarer NOD2 variants in some patients.

Conclusion:

YAOS can masquerade HPFS like FMF. Molecular analysis should cover NOD2 whole gene sequencing to help distinguish these diseases.

References:

[1]Yao Q, et al. Dermatitis as a characteristic phenotype of a new autoinflammatory disease associated with NOD2 mutations. J Am Acad Dermatol. 2013;68(4):624-31.

Trueb B, et al. Coincidence of NOD2-Associated Autoinflammatory Disease (Yao Syndrome) and HCV Infection With Fatal Consequences: Interaction Between Genes and Environment. J Clin Rheumatol. 2018 Dec 28. doi: 10.1097/RHU.0000000000000963. [Epub ahead of print].

China

[2]Yao Q. Research letter: Effectiveness of canakinumab for the treatment of Yao syndrome patients. J Am Acad Dermatol. 2019.

[3]Yao Q, Shen M, McDonald C, Lacbawan F, Moran R, Shen B. NOD2-associated autoinflammatory disease: a large cohort study. Rheumatology (Oxford). 2015;54(10):1904-12.

[4]Yao Q, Shen B. A Systematic Analysis of Treatment and Outcomes of NOD2-Associated Autoinflammatory Disease. Am J Med. 2017;130(3):365 e13- e18.

[5]McDonald C, et al. Alterations in nucleotide-binding oligomerization domain-2 expression, pathway activation, and cytokine production in Yao syndrome. Autoimmunity. 2018;51(2):53-61.

Acknowledgments:

The author is thankful to the statistician, Ms. Erin Taub for her help with making the table.

Disclosure of Interests:

None declared

[Effects of long non-coding RNA FLJ37505 on the proliferation and migration of bladder cancer cells]

Objective: To examine the expression of long-chain non-coding RNA (lncRNA) FLJ37505 in bladder cancer tissues and cell lines, and to analyze the molecular mechanism of FLJ37505 to inhibit the proliferation and migration of bladder cancer cells. Methods: Quantitative Real-time PCR(qPCR) was used to analyze the relative expression of FLJ37505 in 63 cases of bladder cancer tissues and bladder cancer cell lines (T24, J82, 5637, BIU-87 and UM-UC-3). The bladder cancer cell lines with the least expression of FLJ37505 were divided into control group (transfected with blank plasmid) and FLJ37505 group (transfected with a plasmid carrying the FLJ37505 sequence) according to random number method. MTS assay and scratch assay were used to detect the effect of up-regulation of FLJ37505 expression on cell proliferation and migration. Bioinformatics predicts the target gene of FLJ37505. The dual luciferase reporter system detects the binding of FLJ37505 to the target gene. qPCR and Western blot were used to detect the effect of FLJ37505 on the expression of target gene. Results: Compared with adjacent tissues, FLJ37505 expression was lower in bladder cancer tissue [(4.90±0.79) vs (0.89±0.28), P<0.05]. Compared with human normal bladder tubular epithelial cells, the expression of FLJ37505 was lower in bladder cancer cell lines (P<0.05), and FLJ37505 has the lowest expression in UM-UC-3 cells (P<0.01). Compared with the control group, the expression of FLJ37505 in UM-UC-3 cells of FLJ37505 group was higher [(0.79±0.04) vs (9.92±1.17), P<0.01]. Compared with the control group, the proliferation ability of UM-UC-3 cells in FLJ37505 group was inhibited (P<0.05), and the cell migration ability was also inhibited (P<0.01). Bioinformatics showed that the target gene of FLJ37505 is miR-203a-3p, and the target gene of miR-203a-3p is inositol polyphosphate 4-phosphatase typeⅡ (INPP4B). The dual luciferase reporter gene system showed that FLJ37505 could complement the miR-203a-3p (P<0.01), and miR-203a-3p could complement the INPP4B mRNA (P<0.01). Compared with the control group, the expression of miR-203a-3p was lower [(1.00±0.05) vs (0.20±0.02), P<0.01], the expression of INPP4B in mRNA and protein levels of UM-UC-3 cells in FLJ37505 group was significantly increased (all P<0.01). Conclusions: The expression of FLJ37505 was significantly decreased in bladder cell carcinoma and bladder cancer cells. Up-regulation of FLJ37505 significantly inhibits the proliferation and migration of bladder cell carcinoma UM-UC-3 cells, and the mechanism might be up-regulating the expression of the INPP4B gene by adsorbing miR-203a-3p.

O-GlcNAcylation promotes malignant phenotypes of bladder cancer cells

O-GlcNAcylation (O-GlcNAc) is a posttranslational modification that is mediated by O-GlcNAc-transferase (OGT) and reversed by O-GlcNAcase (OGA). Increasing evidence indicates that protein O-GlcNAcylation is increased in various types of cancer. In the present study, we aimed to evaluate the expression and function of both OGT and OGA in bladder cancer cells in vitro and in vivo. Expression data of OGT and OGA at the mRNA level was obtained from the Oncomine database. Effects of OGT and OGA on cell proliferate, invasive, and migratory abilities were assessed using MTT, wound healing, cell invasive assay, and cell cycle analysis. In vivo assay was also performed in nude mice. The results revealed that the expression of OGT in bladder cancer tissues was higher than that of normal tissues, while the OGA level was found to be lower in cancer tissues. We also found that knockdown of OGT could inhibit cell proliferation, migration, invasion, and induce cell cycle arrest, while these are reversed when OGA is inhibited. We also observed that O-GlcNAcylation could promote tumor formation in vivo, compared with a negative control. In summary, this study describes the oncogenic role of O-GlcNAcylation in bladder cancer cells.

Decreased expression of SorCS1 in colorectal cancer: An independent predictor of poor prognosis

Previously, we identified that sortilin related VPS10 domain containing receptor 1 (SorCS1) was hypermethylated in colorectal cancer (CRC) tissues. Here, we aimed to investigate the association between CRC and SorCS1. DNA methylation was determined by methylation-specific polymerase chain reaction (MSP) or quantitative real-time methylation analysis (MethyLight). Colorectal cancer tissue specimens from 239 patients that had undergone surgical treatment were evaluated using immunohistochemistry (IHC) analysis for the expression of SorCS1 and correlated with clinicopathological variables and prognosis. We found that SorCS1 was hypermethylated in CRC cell lines and 67.5% (27/40) CRC tumor tissues. The loss of SorCS1 mRNA (p<0.001) and protein expression (p=0.033) were highly correlated with promoter methylation. In addition, SorCS1 expression was significantly increased in younger patients (p=0.006), low CEA level (p<0.001) and pT1-2 stage (p=0.005). Survival analysis revealed that decreased expression of SorCS1 was an independent factor for predicting the increased risk of recurrence (p=0.024) and poor overall survival (p=0.006). Subgroup analysis for CEA level, pT and pN classifications showed that SorCS1 retained its stratified significance only in patients with low CEA level, pT3-4 tumors and pN1-2 lymph node status. Our findings suggest that SorCS1 is epigenetically inactivated in a substantial fraction of CRC, and its expression may be a promising prognostic factor in CRC patients.

A thermostable 5-enolpyruvylshikimate-3-phosphate synthase from Thermotoga maritima enhances glyphosate tolerance in Escherichia coli and transgenic Arabidopsis

5-Enolpyruvylshikimate-3-phosphate synthase (EPSPS) overexpression, attempting to provide excess EPSPS to combine with glyphosate, is one way to improve glyphosate resistance of plants. The EPSPS in extremophiles which is selected by nature to withstand the evolutionary pressure may possess some potential-specific biological functions. In this study, we reported the cloning, expression and enzymatic characterization of a novel Class II EPSPS AroAT. maritima from Thermotoga maritima MSB8. The enzyme showed low sequence identities with other EPSPSs, and was one of the most thermostable EPSPSs so far, which showed the optimum enzyme activity at 80 °C. The enzyme maintains the activity below 50 °C and in a wide range of pH 4.0-10, which indicated its stability under rough environment, especially in tropical regions and alkaline soil. Excellent Ki/Km value of AroAT. maritima suggested that the enzyme showed powerful competitive binding capacity of PEP over glyphosate and high glyphosate tolerance. Furthermore, aroAT. maritima gene was transformed into Arabidopsis thaliana. The transgenic lines were resistant to 15 mM glyphosate, which proved the application value in the cultivation of glyphosate-tolerant plants.

P6550Right ventricular apical pacing vs. non-right ventricular apical pacing induced tricuspid regurgitation: implication of 3D echocardiographic location of leads

Background

Pacemaker, device leads have been reported to cause tricuspid regurgitation (TR) of variable degrees. It is different between RVA pacing and None-RVA pacing in device-related TR. Few articles indicate this area. Objectives: We sought to evaluate (1) TR degree in patients with right ventricular apical (RVA) pacing vs. none-RVA pacing; (2) the relationship of lead-position between RVA vs. none-RVA pacing associated with TR undergo 3-dimensional echocardiography (3DE).

Methods

Conventional echocardiography performed in 458 patients after pacemaker implantation. In addition, 284 patients with pre-pacemaker implantation echocardiography available were included to evaluate the development of significant TR prospectively.

Results

RVA pacing patients had a higher frequency of significant TR (degree≥2) compared to none-RVA pacing (63% vs. 42%, p-value <0.01). For RVA pacing, the lead was more likely to position at the anterior, posterior and septal compared to none-RVA pacing (51% vs. 33%, p-value <0.01). Importantly, leads were more likely to be positioned in the central portion with none-RVA pacing compared to RVA pacing (30% vs. 13%, p-value <0.01). Among 284 patients with pre-& post-implantation echocardiography, RVA pacing is associated with the development of significant TR compared to none-RVA pacing (59% vs. 41%, P=0.012).

Factors Associated with Significant TR Univariate p-value Multivariate p-value Age 1.035 (1.016–1.055) <0.01 1.025 (1.005–1.047) 0.02 Duration 1.003 (1.001–1.006) 0.02 1.001 (0.998–1.004) 0.62 Male 0678 (0.468–0.980) 0.04 0.657 (0.436–0.991) 0.05 Pre-AF 2.623 (1.740–3.955) <0.01 1.162 (0.588–2.295) 0.67 Post-AF 3.529 (2.329–5.346) <0.01 2.671 (1.566–4.556) <0.01 DDDR 0.428 (0.236–0.777) 0.01 0.724 (0.336–1.563) 0.41 RVA 2.451 (1.673–3.589) <0.01 1.962 (1.266–3.042) <0.01

3D TTE view of the device leads in TVs

Conclusions

The study demonstrates that RVA pacing is more likely to develop significant TR compared to none-RVA pacing. Significantly, this study is the first details to demonstrate that lead impingement is one of the possible mechanisms that could explain the higher frequency of TR in RVA pacing compared to none-RVA pacing by 3DE.

Acknowledgement/Funding

This manuscript is partially supported by the Summit Grant from the University of Hong Kong and Queen Mary Hospital.

Overexpression of a trypanothione synthetase gene from Trypanosoma cruzi, TcTrys, confers enhanced tolerance to multiple abiotic stresses in rice

Plants are frequently exposed to variable environmental stresses that adversely affect plant growth, development and agricultural production. In this study, a trypanothione synthetase gene from Trypanosoma cruzi, TcTryS, was chemically synthesized and its roles in tolerance to multiple abiotic stresses were functionally characterized by generating transgenic rice overexpressing TcTryS. Overexpression of TcTryS in rice endows transgenic plants with hypersensitivity to ABA, hyposensitivity to NaCl- and mannitol-induced osmotic stress at the seed germination stage. TcTryS overexpression results in enhanced tolerance to drought, salt, cadmium, and 2,4,6-trichlorophenol stresses in transgenic rice, simultaneously supported by improved physiological traits. The TcTryS-overexpression plants also accumulated greater amounts of proline, less malondialdehyde and more transcripts of stress-related genes than wild-type plants under drought and salt stress conditions. In addition, TcTryS might play a positive role in maintaining chlorophyll content under 2,4,6-trichlorophenol stress. Histochemical staining assay showed that TcTryS renders transgenic plants better ROS-scavenging capability. All of these results suggest that TcTryS could function as a key regulator in modulation of abiotic stress tolerance in plant, and may have applications in the engineering of economically important crops.

Construction of an Escherichia coli strain to degrade phenol completely with two modified metabolic modules

Phenol is a common water pollutant because of its broad industrial applications. Biological method is a promising alternative to conventional physical and chemical methods for removing this toxic pollutant from the environment. In this study, two metabolic modules were introduced into Escherichia coli, the widely used host for various genetic manipulations, to elucidate the metabolic capacity of E. coli for phenol degradation. The first module catalysed the conversion of phenol to catechol, whereas the second module cleaved catechol into the three carboxylic acid circulating intermediates by the ortho-cleavage pathway. Phenol was completely degraded and imported into the tricarboxylic acid cycle by the engineered bacteria. Proteomics analysis showed that all genes in the phenol degradation pathway were over-expressed and affected cell division and energy metabolism of the host cells. Phenol in coking wastewater was degraded powerfully by BL-phe/cat. The engineered E. coli can improve the removal rate and shorten the processing time for phenol removal and has considerable potential in the treatment of toxic and harmful pollutants.

Update of Guidelines for laparoscopic treatment of ventral and incisional abdominal wall hernias (International Endohernia Society (IEHS))-Part A

Abstract

In 2014, the International Endohernia Society (IEHS) published the first international “Guidelines for laparoscopic treatment of ventral and incisional abdominal wall hernias.” Guidelines reflect the currently best available evidence in diagnostics and therapy and give recommendations to help surgeons to standardize their techniques and to improve their results. However, science is a dynamic field which is continuously developing. Therefore, guidelines require regular updates to keep pace with the evolving literature.

Methods

For the development of the original guidelines, all relevant literature published up to year 2012 was analyzed using the ranking of the Oxford Centre for Evidence-Based Medicine. For the present update, all of the previous authors were asked to evaluate the literature published during the recent years from 2012 to 2017 and revise their statements and recommendations given in the initial guidelines accordingly. In two Consensus Conferences (October 2017 Beijing, March 2018 Cologne), the updates were presented, discussed, and confirmed. To avoid redundancy, only new statements or recommendations are included in this paper. Therefore, for full understanding both of the guidelines, the original and the current, must be read. In addition, the new developments in repair of abdominal wall hernias like surgical techniques within the abdominal wall, release operations (transversus muscle release, component separation), Botox application, and robot-assisted repair methods were included.

Results

Due to an increase of the number of patients and further development of surgical techniques, repair of primary and secondary abdominal wall hernias attracts increasing interests of many surgeons. Whereas up to three decades ago hernia-related publications did not exceed 20 per year, currently this number is about 10-fold higher. Recent years are characterized by the advent of new techniques—minimal invasive techniques using robotics and laparoscopy, totally extraperitoneal repairs, novel myofascial release techniques for optimal closure of large defects, and Botox for relaxing the abdominal wall. Furthermore, a concomitant rectus diastasis was recognized as a significant risk factor for recurrence. Despite insufficient evidence with respect to these new techniques, it seemed to us necessary to include them in the update to stimulate surgeons to do research in these fields.

Conclusion

Guidelines are recommendations based on best available evidence intended to help the surgeon to improve the quality of his daily work. However, science is a continuously evolving process, and as such guidelines should be updated about every 3 years. For a comprehensive reference, however, it is suggested to read both the initial guidelines published in 2014 together with the update. Moreover, the presented update includes also techniques which were not known 3 years before.

Therapeutic effect of pregabalin on radiotherapy-induced trismus in nasopharyngeal carcinoma patients

AIMS

To evaluate the effect of pregabalin on radiotherapy-induced trismus in patients with nasopharyngeal carcinoma, a hospital-based, clinical retrospective cohort study was conducted.

MATERIALS AND METHODS

Data were collected on patients diagnosed with radiotherapy-induced trismus from March 2014 and March 2016 in the department of neurology in our hospital. Patients in the treatment group were administrated pregabalin for 8 weeks combined with rehabilitation, while the control group only received rehabilitation. The clinical therapeutic effects were observed and evaluated by mandibular motion, severity of trismus measured by late effects of normal tissues/subjective and objective medical analysis (LENT/SOMA) scales, and quality of life (QOL) assessed using the World Health Organization QOL instrument (WHOQOL-BREF) at baseline, week 4 and week 8 during treatment in these two groups, respectively.

RESULTS

In the treatment group, the number of patients with improvement on maximal vertical dimension (MVD) was significantly more than controls at week 4 and week 8 (P=0.013, P=0.004, respectively). Moreover, at week 4 and week 8, the severity of trismus was both significantly improved on LENT/SOMA grade in treatment group (P=0.047, P=0.032, respectively). And at week 8, the physical health and the whole life domain of the WHOQOL-BREF score were significantly increased (P=0.037, P=0.034, respectively). In the treatment group, 11 patients (36.7%) presented dizziness, and 7 patients (23.3%) presented somnolence.

CONCLUSIONS

Administration of pregabalin, in adjunct to rehabilitation, might provide a better outcome in patients with radiotherapy-induced trismus.

Heterologous Expression and Characterization of a Laccase from Laccaria bicolor in Pichia pastoris and Arabidopsis thaliana

Laccases can oxidize a variety of phenolic and non-phenolic substrates including synthetic dyes. In this research, a laccase gene Lcc9 from Laccaria bicolor was chemically synthesized and optimized to heterogeneous expression in Pichia pastoris and Arabidopsis thaliana. The properties of recombinant laccase expressed by P. pastoris were investigated. The laccase activity was optimal at 3.6 pH and 40°C. It exhibited K_m and V_max values of 0.565 mmol l⁻¹ and 1.51 μmol l⁻¹ min⁻¹ for ABTS respectively. As compared with untransformed control plants, the laccase activity in crude extracts of transgenic lines exhibited a 5.4 to 12.4-fold increase. Both laccases expressed in transgenic P. pastoris or A. thaliana could decolorize crystal violet. These results indicated that L. bicolor laccase gene may be transgenically exploited in fungi or plants for dye decolorization.