Arsenic behavior in soil-plant system under the manure application with the combination of antibiotic and roxarsone.

Limited attention has been given to the interaction between antibiotics and arsenic in the soil-plant system. In this investigation, Medicago sativa seedlings were grown in soil treated with cow manure containing oxytetracycline (OTC) or sulfadiazine (SD), as well as arsenic (introduced through roxarsone, referred to as ROX treatment). The study revealed a notable increase in As(III) and dimethylarsinic acid (DMA(V)) levels in rhizosphere soils and plant root tissues as arsenic contamination intensified in the presence of antibiotics, while concentrations of As(V) and monomethylarsonic acid (MMA(V)) decreased. Conversely, elevated antibiotic presence resulted in higher levels of As(V) but reduced DMA concentrations in both rhizosphere soils and plant root tissues in the presence of arsenic. The arsenic biotransformation gene aioA was inhibited by arsenic contamination when antibiotics were present, and suppressed by antibiotic contamination in the presence of arsenic, especially in SD treatments, resulting in reduced expression levels at higher SD concentrations. Conversely, the arsM gene exhibited consistent upregulation under all conditions. However, its expression was found to increase with higher concentrations of ROX in the presence of antibiotics, decrease with increasing SD concentrations, and initially rise before declining with higher levels of OTC in the presence of arsenic. Bacterial genera within the Proteobacteria phylum, such as Geobacter, Lusitaniella, Mesorhizobium, and Methylovirgula, showed significant co-occurrence with both aioA and arsM genes. Correlation analysis demonstrated associations between the four arsenic species and the two arsenic biotransformation genes, emphasizing pH as a critical factor influencing the transformation and uptake of different arsenic species in the soil-plant system. The combined stress of antibiotics and arsenic has the potential to modify arsenic behavior and associated risks in soil-plant systems, highlighting the necessity of considering this interaction in future research endeavors.

The application of organic selenium (SeMet) improve the photosynthetic characteristics, yield and quality of hybrid rice.

Rice is an important food in the world, and selenium (Se) is a necessary trace element for the human. So the effects of selenomethionine (SeMet) on photosynthetic capacity, yield and quality of rice at different stages were studied. The results show that SeMet can increase the Ppotosynthetic capacity of rice leaves during each growth stage, the effect of 5 mg/L SeMet treatment was the most significant. At the mature stage of rice, SeMet significantly increased rice yield and total plant biomass, 7.5and 5 mg/L SeMet treatments had the most significant effects, respectively. In addition, SeMet significantly improved the content of Se and processing quality of rice, decreased chalkiness, inhibited amylose synthesis, and optimized flavor. The above indices showed the best results after treatment with 5 mg/L SeMet. It is hoped that this study will provide a theoretical basis for the application of organic selenium in rice production.

Tannic acid-assisted upcycling of Cu from waste printed circuit boards to an efficient peroxymonosulfate catalyst for the degradation of organic pollutants.

The recovery of metals from solid waste for use as heterogeneous catalysts to activate peroxymonosulfate (PMS) for organic wastewater treatment is a promising, environmentally friendly and economical strategy. Herein, we present a facile and versatile strategy for upcycling copper (Cu) from waste printed circuit boards (PCBs) to Cu oxides supported on a three-dimensional carbon framework (10PCBs-Cu-TA) with the aid of tannic acid (TA). Compared to the PCBs-Cu synthesized without TA, introducing TA into 10PCBs-Cu-TA reduced Cu leaching, enhanced crystallinity, promoted electron transfer, and increased the number of oxygen vacancies. Moreover, 10PCBs-Cu-TA exhibited superior catalytic activity in activating PMS for the degradation of reactive brilliant blue KN-R, exceeding the activity of 10Cu-TA prepared using commercial Cu(NO3)2·3H2O. This enhanced performance may be attributed to the higher specific surface area and oxygen vacancies of 10PCBs-Cu-TA. The 10PCBs-Cu-TA/PMS system also exhibited broad catalytic universality and adaptability to various contaminants and water matrices. Quenching experiments, electron paramagnetic resonance analysis, and electrochemical measurements indicated that radical and non-radical processes jointly contributed to KN-R degradation. The proposed strategy for upcycling Cu from waste PCBs into functional materials provides novel insights into the utilization of solid waste and the development of PMS activators.

Anti-Melanoma Activity of Single Intratumoral Injection of ZnPc Micelles Mixed With in situ Gel in B16 Bearing Mouse.

Photodynamic therapy (PDT) is a potential treatment strategy for melanoma. As a second-generation photosensitizer, Zinc phthalocyanine (ZnPc) has many advantages for anti-tumor PDTs, such as strong absorption in the red and near infrared regions, high photo and chemical stability, etc. However, ZnPc has a poor water solubility and is apt to aggregate due to the π-π interaction between molecules, which limits its applications. In this study, various solvents and surfactants were screened for dissolving ZnPc and preparing ZnPc@SDC-TPGS micelle and thermosensitive in situ gel. After the cytotoxic effects of thermosensitive gels on PDT were tested, the antitumor effects on PDT of them in mice by intratumoral injection were evaluated, including body weight, and tumor weight, volume and morphology. The cell death pathway and the relationship of reactive oxygen species yield with apoptotic rate of tumor cells induced by ZnPc in situ gel were investigated. The results were that N-methyl-pyrrolidone (NMP) mixed with 2 % SDC and aqueous solution containing 2 % TPGS and 2 % SDC were used to synthesize ZnPc@SDC-TPGS micelle and the thermosensitive in situ gel. The cytotoxic effects of thermosensitive gels showed good tumor suppression of ZnPc@SDC-TPGS in situ gel and no toxicity of the blank gel. Intratumoral injection in situ gel containing 3 µg ZnPc under irradiation demonstrated good tumor inhibition in mice with melanoma. Apoptosis has been established as the primary pathway of cell death, and the production of reactive oxygen species (ROS) plays a crucial role in cellular apoptosis induced by ZnPc@SDC-TPGS in situ gel. In conclusion, the intratumoral injection of ZnPc@SDC-TPGS thermosensitive in situ gel provides a promising local treatment option for melanoma.

Bacteroides fragilis ubiquitin homologue drives intraspecies bacterial competition in the gut microbiome.

Interbacterial antagonism and associated defensive strategies are both essential during bacterial competition. The human gut symbiont Bacteroides fragilis secretes a ubiquitin homologue (BfUbb) that is toxic to a subset of B. fragilis strains in vitro. In the present study, we demonstrate that BfUbb lyses certain B. fragilis strains by non-covalently binding and inactivating an essential peptidyl-prolyl isomerase (PPIase). BfUbb-sensitivity profiling of B. fragilis strains revealed a key tyrosine residue (Tyr119) in the PPIase and strains that encode a glutamic acid residue at Tyr119 are resistant to BfUbb. Crystal structural analysis and functional studies of BfUbb and the BfUbb-PPIase complex uncover a unique disulfide bond at the carboxy terminus of BfUbb to mediate the interaction with Tyr119 of the PPIase. In vitro coculture assays and mouse studies show that BfUbb confers a competitive advantage for encoding strains and this is further supported by human gut metagenome analyses. Our findings reveal a previously undescribed mechanism of bacterial intraspecies competition.

Antibiotics and their associations with antibiotic resistance genes and microbial communities in estuarine and coastal sediment of Quanzhou Bay, Southeast China.

The antibiotic concentrations spanned from 11.2 to 173.8 ng/g, with quinolones and tetracyclines being observed to be prevalent. The amount of microbial biomass as determined by Phospholipid fatty acid (PLFA) ranged from 2.92 to 10.99 mg kg-1, with G- bacteria dominating. A total of 254 distinct ARGs and 10 MEGs were identified, with multidrug ARGs having the highest relative abundance (1.18 × 10-2 to 3.00 × 10-1 copies/16S rRNA gene copies), while vancomycin and sulfonamide resistance genes were the least abundant. Results from canonical-correlation analyses combined with redundancy analysis indicated that macrolides were significantly related to the shifts of microbial community structure in sediments, particularly in G+ bacteria that were more sensitive to antibiotic residues. It was observed that sulfonamide ARGs had a greater correlation with residual antibiotics than other ARGs. This study provided a field evidence that multiple residual antibiotics from coastal sites could cause fundamental shifts in microbial community and their associated ARGs.

Microbial community structure and antibiotic resistance profiles in sediments with long-term aquaculture history.

The aim of this investigation was to examine the microbial populations and their resistance patterns towards antibiotics, including the impact of nitrogen metabolism in response to the reintroduction of antibiotics, as well as the presence of resistance genes in sediments from shrimp ponds that have been utilized for extended periods of 5, 15, and over 30 years. Results showed that the sediments exhibited a high prevalence of Proteobacteria, Bacteroidetes, Planctomycetes, Chloroflexi, and Oxyphotobacteria as the most abundant bacterial phyla, accounting for 70.35-77.43% of the total bacterial community. The five most abundant phyla of fungi detected in all sediments, namely Rozellomycota, Ascomycota, Aphelidiomycota, Basidiomycota, and Mortierellomycota, constituted 24.26-32.54% of the total fungal community. It was highly probable that the Proteobacteria and Bacteroidetes phyla serve as the primary reservoir of antibiotic-resistant bacteria (ARB) in the sediment, which included various genera like Sulfurovum, Woeseia, Sulfurimonas, Desulfosarcina, and Robiginitalea. Among these genera, Sulfurovum appeared to be the most widespread in the sediment of aquaculture ponds that have been in operation for more than three decades, while Woeseia dominated in ponds that have been recently reclaimed and have a 15-year aquaculture history. Antibiotic resistance genes (ARGs) were categorized into seven distinct groups according to their mechanism of action. The prevalence of multidrug-resistant ARGs was found to be the highest among all types, with an abundance ranging from 8.74 × 10-2 to 1.90 × 10-1 copies per 16S rRNA gene copies. The results of a comparative analysis of sediment samples with varying aquaculture histories indicated that the total relative abundance of ARGs was significantly diminished in sediment with a 15-year aquaculture history as opposed to sediment with either a 5-year or 30-year aquaculture history. Another assessment of antibiotic resistances in aquaculture sediments involved an examination of the effects of reintroducing antibiotics on nitrogen metabolism processes. The findings revealed that the rates of ammonification, nitrification, and denitrification in the sediment with a history of 5 years and 15 years, decreased as the concentration of oxytetracycline increased from 1 to 300, and 2000 mg/kg, and inhibitory effects were found to be less pronounced in sediments with a 5-year history compared to those with a 15-year history. In contrast, oxytetracycline exposure led to a significant decrease in the rates of these processes in aquaculture pond sediments with a >30 years of aquaculture history across all the concentrations tested. The emergence and dissemination of antibiotic resistance profiles in aquaculture environments requires attention in future aquaculture management.

Impacts of Eucalyptus plantation on soil and water losses in a typical small watershed in mountainous area of southern China.

Unreasonable exploitation of artificial forest causes severe soil erosion in the mountainous areas of sou-thern China. The spatial-temporal variations of soil erosion in typical small watershed with artificial forest has signifi-cant implications for artificial forest exploitation and sustainable development of mountainous ecological environment. In this study, we used revised universal soil loss equation (RUSLE) and geographic information system (GIS) to evaluate the spatial and temporal variations of soil erosion and its key drivers of Dadingshan watershed in mountainous area of western Guangdong. The results showed that the erosion modulus was 1948.1 t·km-2·a-1 (belonging to light erosion) in the Dadingshan watershed. However, the spatial variation of soil erosion was substantial, with variation coefficient of 5.12. The maximal soil erosion modulus was 191127 t·km-2·a-1. Slight erosion (<500 t·km-2·a-1) accounted for 80.6% of the total watershed area. The moderate erosion and above (>2500 t·km-2·a-1) were mainly distributed in young Eucalyptus forest area with less than 30% of the vegetation coverage, which contributed nearly 75.7% of total soil erosion. During 2014-2019, the interannual variations of mean erosion of Dadingshan catchment was modest, but the spatial variation of soil erosion was large. Vegetation cover, slope, and rainfall were key drivers of such variation. The destruction of natural vegetation resulted by plantation exploitation was the primary cause of soil erosion in afforestation areas. Soil erosion significantly increased with the increases of slope gradient in the young forest area, which was aggravated by extreme rainfall. However, soil erosion gradually decreased with the increases of the age of Eucalypt plantation. Therefore, the hot spot of soil erosion was young forest areas of Eucalypt plantation with slope >25°, and the key period for soil erosion control was the first 2-3 years after Eucalyptus planting. We suggested that reasonable afforestation measures should be used in area with >25° slopes, and that the destruction of natural vegetation should be avoided on hillslope with >35° slope gradient. The road construction standards and forest management should be further improved to address the challenge of extreme rainfalls.

Robustness optimization for rapid prototyping of functional artifacts based on visualized computing digital twins.

This study presents a robustness optimization method for rapid prototyping (RP) of functional artifacts based on visualized computing digital twins (VCDT). A generalized multiobjective robustness optimization model for RP of scheme design prototype was first built, where thermal, structural, and multidisciplinary knowledge could be integrated for visualization. To implement visualized computing, the membership function of fuzzy decision-making was optimized using a genetic algorithm. Transient thermodynamic, structural statics, and flow field analyses were conducted, especially for glass fiber composite materials, which have the characteristics of high strength, corrosion resistance, temperature resistance, dimensional stability, and electrical insulation. An electrothermal experiment was performed by measuring the temperature and changes in temperature during RP. Infrared thermographs were obtained using thermal field measurements to determine the temperature distribution. A numerical analysis of a lightweight ribbed ergonomic artifact is presented to illustrate the VCDT. Moreover, manufacturability was verified based on a thermal-solid coupled finite element analysis. The physical experiment and practice proved that the proposed VCDT provided a robust design paradigm for a layered RP between the steady balance of electrothermal regulation and manufacturing efficacy under hybrid uncertainties.

Effects of common afforestation tree species on soil bacterial community and microbial functional guilds in subtropical forests.

To understand the effects of common afforestation tree species on soil microbial community in subtropical forests, seven different tree species were selected as the research object, including Pinus massoniana, Mytilaria laosensis, Liquidambar formosana, Ilex chinensis, Michelia macclurei, Quercus acutissima and Betula luminifera. Based on 16S rRNA high-throughput sequencing and real-time quantitative PCR techniques, we explored the effects of different tree species on soil bacterial community composition, diversity and microbial functional guilds. The results showed that Acidobacteria, Proteobacteria, and Actinobacteria were the dominant bacterial phyla, and that there was no significant difference in bacterial diversity or richness index among different tree species. Results of redundancy analysis suggested that soil bulk density, soil C/N, litter nitrogen content, and litter C/N were the predominant factors determining soil bacterial community composition. The afforestation tree species had significant effects on functional gene abundances of ammonia oxidizing archaea, ammonia oxidizing bacteria and complete ammonia oxidation. Comammox were dominant in abundance. Ammonia oxidizing archaea amoA gene was the only type whose abundance showed significant correlation with soil nitrate content, suggesting that ammonia oxidizing archaea could play a dominant role in the autotrophic nitrification in the acidic subtropical forest soils. The afforestation tree species had significant effects on functional gene abundances of ammonia oxidizing microorganisms. Results of correlation analysis showed that litter nitrogen content was the driving factor for the abundance of ammonia oxidizing microorganisms. Our study provided strong evidence that the responses of soil microbial functional guilds to tree species were more sensitive than bacterial community composition. Future studies should explore the mechanisms of tree plantations on forest ecosystem functioning from the perspective of microbial functional guilds.

Adaptation of Rhizosphere Microbial Communities to Continuous Exposure to Multiple Residual Antibiotics in Vegetable Farms.

The constant application of manure-based fertilizers in vegetable farms leads to antibiotic residue accumulation in soils, which has become a major stressor affecting agroecosystem stability. The present study investigated the adaptation profiles of rhizosphere microbial communities in different vegetable farms to multiple residual antibiotics. Multiple antibiotics, including trimethoprim, sulfonamides, quinolones, tetracyclines, macrolides, lincomycins, and chloramphenicols, were detected in the vegetable farms; the dominant antibiotic (trimethoprim) had a maximum concentration of 36.7 ng/g. Quinolones and tetracyclines were the most prevalent antibiotics in the vegetable farms. The five most abundant phyla in soil samples were Proteobacteria, Actinobacteria, Acidobacteria, Chloroflexi and Firmicutes, while the five most abundant phyla in root samples were Proteobacteria, Actinobacteria, Bacteroidetes, Firmicutes and Myxococcota. Macrolides were significantly correlated with microbial community composition changes in soil samples, while sulfonamides were significantly correlated with microbial community composition changes in root samples. Soil properties (total carbon and nitrogen contents and pH) influenced the shifts in microbial communities in rhizosphere soils and roots. This study provides evidence that low residual antibiotic levels in vegetable farms can shift microbial community structures, potentially affecting agroecosystem stability. However, the degree to which the shift occurs could be regulated by environmental factors, such as soil nutrient conditions.

Nonadiabatic dynamics studies of the H(2S) + RbH(X1Σ+) reaction: based on new diabatic potential energy surfaces.

The global diabatic potential energy surfaces (PESs) that correspond to the ground (12A') and first excited states (22A') of the RbH2 system PES are constructed based on 17 786 ab initio points. The neural network method is used to fit the PESs and the topographic features of the new diabatic PESs are discussed in detail. Based on the newly constructed diabatic PESs, the dynamics calculations of the H(2S) + RbH(X1Σ+) → Rb(52S) + H2(X1Σg +)/Rb(52P) + H2(X1Σg +) reactions are performed using the time-dependent wave packet method. The dynamics properties of these two channels such as the reaction probabilities, integral cross sections, and differential cross sections (DCSs) are calculated at state-to-state level of theory. The nonadiabatic effects are discussed in detail, and the results indicate that the adiabatic results are overestimated from the dynamics values. The DCSs of these two channels are forward biased, which indicates that the abstraction mechanism plays a dominant role in the reaction.

Waste eggshell-supported CuO used as heterogeneous catalyst for reactive blue 19 degradation through peroxymonosulfate activation (CuO/eggshell catalysts activate PMS to degrade reactive blue 19).

Advanced oxidation processes play an important role in the removal of organic pollutants from wastewater, in which it is essential to develop an eco-friendly, effective, stable, and inexpensive catalyst. Herein, waste eggshell-supported copper oxide (CuO/eggshell) was synthesized via a facile method and employed as peroxymonosulfate (PMS) activator for the elimination of reactive blue 19 (RB19). CuO/eggshell exhibited high degradation efficiency of RB19 (approximately 100%) by activation of PMS under the optimum conditions of 20 mg/L RB19, 0.2 g/L CuO/eggshell, 0.36 mM PMS, and initial pH 7.12 within 20 min. In addition, the effects of catalyst dosage, PMS concentration, initial pH, inorganic ions, and humic acid on RB19 degradation were investigated. Scavenging experiments and electron paramagnetic resonance revealed that multiple reactive oxygen species, including sulfate radicals (SO4·-), hydroxyl radicals (·OH), superoxide radicals (O2·-), and singlet oxygen (1O2), contributed to RB19 degradation, and 1O2 played a dominant role. Finally, a possible PMS activation mechanism was proposed. This study suggests that loading catalytically active components onto waste eggshell is eco-friendly and effective for enhancing the degradation of dyes from wastewater.

Efficacy of acupuncture at ghost points combined with fluoxetine in treating depression: A randomized study.

BACKGROUND: Depression affects more than 350 million people worldwide. In China, 4.2% (54 million people) of the total population suffers from depression. Psychotherapy has been shown to change cognition, improve personality, and enhance the ability to cope with difficulties and setbacks. While pharmacotherapy can reduce symptoms, it is also associated with adverse reactions and relapse after drug withdrawal. Therefore, there has been an increasing emphasis placed on the use of non-pharmacological therapies for depression. The hypothesis of this study was that acupuncture at ghost points combined with fluoxetine would be more effective than fluoxetine alone for the treatment of depression. AIM: To investigate the efficacy of acupuncture at ghost points combined with fluoxetine for the treatment of patients with depression. METHODS: This randomized controlled trial included patients with mild to moderate depression (n = 160). Patients received either acupuncture at ghost points combined with fluoxetine (n = 80) or fluoxetine alone (control group, n = 80). Needles were retained in place for 30 min, 5 times a week; three treatment cycles were administered. The Mann-Whitney U test was used to compare functional magnet resonance imaging parameters, Hamilton depression rating scale (HAMD) scores, and self-rating depression scale (SDS) scores between the acupuncture group and control group. RESULTS: There were no significant differences in HAMD or SDS scores between the acupuncture group and control group, before or after 4 wk of treatment. The acupuncture group exhibited significantly lower HAMD and SDS scores than the control group after 8 wk of treatment (P < 0.05). The acupuncture group had significantly lower fractional Amplitude of Low Frequency Fluctuations values for the left anterior wedge leaf, left posterior cingulate gyrus, left middle occipital gyrus, and left inferior occipital gyrus after 8 wk. The acupuncture group also had significantly higher values for the right inferior frontal gyrus, right insula, and right hippocampus (P < 0.05). After 8 wk of treatment, the effective rates of the acupuncture and control groups were 51.25% and 36.25%, respectively (P < 0.05). CONCLUSION: The study results suggest that acupuncture at ghost points combined with fluoxetine is more effective than fluoxetine alone for the treatment of patients with mild to moderate depression.

Ecological response to antibiotics re-entering the aquaculture environment with possible long-term antibiotics selection based on enzyme activity in sediment.

Antibiotics are frequently applied in aquaculture to control infectious diseases and promote aquaculture production. The long-term application of antibiotics can lead to antibiotic resistance within an ecosystem. Herein, we assessed the ecological responses to two antibiotics (oxytetracycline (OTC) and sulfadiazine (SD)) at three concentrations (0 mg/kg (control), 10 mg/kg, and 1000 mg/kg) re-entering the aquaculture sediments of shrimp ponds with an approximately long-term drug application history (5, 15, and more than 30 years) for 2 and 4 months. For the newly reclaimed aquaculture ponds (approximately 5 years), the re-entered OTC significantly promoted urease activity (UA) and peroxidase activity (POA), while inhibited dehydrogenase activity (DHA) and fluorescein diacetate esterase activity (FDA). Meanwhile, the re-entered SD showed promotional effects on POA and DHA, and inhibitory effects on UA and FDA. For ponds with 15 years of aquaculture history, re-entered OTC promoted POA, inhibited FDA, and changed the influencing effects of UA and DHA with exposure time. The re-entered SD showed promotional effects on UA, POA and DHA, and inhibitory effects on FDA. For long-term aquaculture ponds (more than 30 years of aquaculture history), re-entered OTC promoted POA, DHA, and FDA, while it inhibited UA. Meanwhile, SD promoted all four enzyme activities. Pearson correlation analysis indicated that the variances of enzyme responses to the re-entry of antibiotics in the three sediment environments were related with the type, concentration, and exposure time of antibiotics, as well as the sediment properties and aquaculture history. The enzyme activities in the sediment environment from newly reclaimed aquaculture ponds were more sensitive to the re-entered antibiotics, while the enzyme activities displayed a clear tolerance in the sediment environment with more than 30 years of aquaculture history. However, in the sediment environment with 15 years of aquaculture history, the response of the enzyme activities to re-entered antibiotics demonstrated time processes of antibiotic adaptation during antibiotic resistance selection. This study has illustrated the effects of re-entered antibiotics on enzyme activities in the aquaculture environment with long-term antibiotic resistance/tolerance profiles, and further establishes the possible effects on ecosystem functioning in continuous antibiotic selection pressure.

Structural and Functional Analysis of SsaV Cytoplasmic Domain and Variable Linker States in the Context of the InvA-SsaV Chimeric Protein.

The type III secretion (T3S) injectisome is a syringe-like protein-delivery nanomachine widely utilized by Gram-negative bacteria. It can deliver effector proteins directly from bacteria into eukaryotic host cells, which is crucial for the bacterial-host interaction. Intracellular pathogen Salmonella enterica serovar Typhimurium encodes two sets of T3S injectisomes from Salmonella pathogenicity islands 1 and 2 (SPI-1 and SPI-2), which are critical for its host invasion and intracellular survival, respectively. The inner membrane export gate protein, SctV (InvA in SPI-1 and SsaV in SPI-2), is the largest component of the injectisome and is essential for assembly and function of T3SS. Here, we report the 2.11 Å cryo-EM structure of the SsaV cytoplasmic domain (SsaVC) in the context of a full-length SctV chimera consisting of the transmembrane region of InvA, the linker of SsaV (SsaVL) and SsaVC. The structural analysis shows that SsaVC exists in a semi-open state and SsaVL exhibits two major orientations, implying a highly dynamic process of SsaV for the substrate selection and secretion in a full-length context. A biochemical assay indicates that SsaVL plays an essential role in maintaining the nonameric state of SsaV. This study offers near atomic-level insights into how SsaVC and SsaVL facilitate the assembly and function of SsaV and may lead to the development of potential anti-virulence therapeutics against T3SS-mediated bacterial infection. IMPORTANCE Type III secretion system (T3SS) is a multicomponent nanomachine and a critical virulence factor for a wide range of Gram-negative bacterial pathogens. It can deliver numbers of effectors into the host cell to facilitate the bacterial host infection. Export gate protein SctV, as one of the engines of T3SS, is at the center of T3SS assembly and function. In this study, we show the high-resolution atomic structure of the cytosolic domain of SctV in the nonameric state with variable linker conformations. Our first observation of conformational changes of the linker region of SctV and the semi-open state of the cytosolic domain of SctV in the full-length context further support that the substrate selection and secretion process of SctV is highly dynamic. These findings have important implications for the development of therapeutic strategies targeting SctV to combat T3SS-mediated bacterial infection.

[Clinical observation of different surgical methods for metaphyseal sequelae of ulna].

OBJECTIVE: To investigate the effect and safety of ulnar osteochondroma resection, ulnar minimally invasive osteotomy, external fixation and ulnar lengthening in the treatment of forearm deformity of metaphyseal extension of ulna. METHODS: From August 2005 to December 2013, there were 20 cases of ulnar metaphyseal sequelae, including 15 males and 5 females, aged from 7 to 13(10.00±2.34) years, the course of disease ranged for 6 to 11(8.10±1.52) months. The clinical manifestations were shortening of the affected forearm and bending to the ulnar side. The postoperative evaluation included pain, activities of daily living, orthopedic effect and the range of motion of wrist, elbow and forearm. The radiological evaluation included ulnar length, radial joint inclination angle and wrist epiphysis growth. RESULTS: All patients healed without infection. The only operation related to complications was ulnar lengthening, including 1 case of nonunion, 2 cases of ulnar lengthening callus fracture and 1 case of temporary radial nerve palsy. All patients were followed up for 4 to 7.5 years, with an average of (6.03±1.33) years. There were statistically significant differences in changes of wrist radial deviation, ulnar deviation, forearm pronation and supination in all cases (P<0.05). Radiological evaluation parameters (ulnar variance, radial joint angle, wrist slip) were improved, and the differences were statistically significant(P<0.05). The modified Green and O'Brien wrist function scores at the last follow-up were significantly different from those before operation (P<0.05). The clinical effect of wrist joint was significantly different from that before operation (P<0.05). The Mayo elbow function scoreat the latest follow-up was significantly different from that before operation (P<0.05). The clinical effect of elbow joint was significantly different from that before operation (P<0.05). CONCLUSION: Ulnar lengthening is not beneficial to prevent the development of long-term deformity. Simple resection of osteochondroma of distal ulna is beneficial to prevent the development of deformity. Patients with limited rotation of wrist joint and forearm and strong demand for improvement of appearance can be actively treated.

Correlation of Ultrasound Synovitis Joint Count with Disease Activity and Its Longitudinal Variation with Treatment Response to Etanercept in Rheumatoid Arthritis.

More research is needed into rheumatoid arthritis (RA), and ultrasound (US) synovitis is a promising factor for assisting in the management of RA; however, related research is extremely limited. The goal of this study was to evaluate the correlation of US synovitis joint count with clinical features, and its longitudinal changes with treatment response to etanercept in RA. We consecutively enrolled 117 people with active RA being treated with etanercept. US synovitis joint count was evaluated in 28 joints at baseline (W0), week 4 (W4), week 12 (W12) and week 24 (W24) after initiation of etanercept treatment. The mean (±standard deviation), median, inter-quartile range, and total range of the US synovitis joint count at W0 were 9.3 ± 4.0, 9.0, 7.0-11.0 and 2.0-21.0, respectively. US synovitis joint count was positively associated with tenderness joint count, swollen joint count, erythrocyte sedimentation rate, 28-joint Disease Activity Score based on erythrocyte sedimentation rate and Health Assessment Questionnaire-Disability Index score. Then participants were categorized into response and non-response groups according to their response status at W24. Further analyses showed that US synovitis joint count gradually decreased from W0 to W24, and displayed a more notable declining trend in the response group compared with the non-response group. In addition, US synovitis joint count at W0 and W4 was similar between groups, but at W12 and W24 it was markedly decreased in the response group compared with the non-response group. In conclusion, US synovitis joint count correlates with disease activity, and its longitudinal decrease is associated with treatment response to etanercept in RA.

Identification of a C-Glycosyltransferase Involved in Medermycin Biosynthesis.

C-Glycosylation in the biosynthesis of bioactive natural products is quite unique, which has not been studied well. Medermycin, as an antitumor agent in the family of pyranonaphthoquinone antibiotics, is featured with unique C-glycosylation. Here, a new C-glycosyltransferase (C-GT) Med-8 was identified to be essential for the biosynthesis of medermycin, as the first example of C-GT to recognize a rare deoxyaminosugar (angolosamine). med-8 and six genes (med-14, -15, -16, -17, -18, and -20 located in the medermycin biosynthetic gene cluster) predicted for the biosynthesis of angolosamine were proved to be functional and sufficient for C-glycosylation. A C-glycosylation cassette composed of these seven genes could convert a proposed substrate into a C-glycosylated product. In conclusion, these genes involved in the C-glycosylation of medermycin were functionally identified and biosynthetically engineered, and they provided the possibility of producing new C-glycosylated compounds.

Cyclocarya paliurus for Phytomanagement of Lead-Contaminated Soils.

Cyclocarya paliurus seedlings were cultivated in three types of lead (Pb)-contaminated soils with Pb concentration of 305 ± 17 mg/kg (T1), 1964 ± 59 mg/kg (T2) and 3502 ± 107 mg/kg (T3), respectively. The results showed that after 180 days of cultivation, the contents of exchangeable and carbonate-bound Pb fractions significantly decreased in T1 and T2, but increased in T3. The growth indices of C. paliurus seedlings decreased with increasing Pb concentration; however, no difference was found between that in T1 and in Pb-free soil. The Pb concentration in the roots was an order of magnitude higher than that in the stems and in the leaves. The bioconcentration factor (BCF) of the leaves was the lowest among the three tissues investigated, and decreased with the higher concentration of Pb in the soils. These results suggest that C. paliurus can be used as a sustainable and profitable plant for the phytomanagement of Pb-contaminated soil.