OBJECTIVE: To compare the complementation of magnetic resonance imaging (MRI) to prenatal ultrasound (US) with prenatal US alone in detecting orofacial clefts in high-risk fetuses. DESIGN: A network meta-analysis. SETTING: Literature retrieval in PubMed, EMBASE, and Cochrane library, and meta-analysis based on STATA 14.0. PATIENTS: Fetuses were at high-risk for orofacial clefts. INTERVENTIONS: Prenatal US and the complementation of MRI to prenatal US. MAIN OUTCOME MEASURES: The pooled sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), diagnostic odds ratio (DOR), and area under the curve (AUC). RESULTS: Thirteen studies involving 776 patients were included. Direct meta-analysis showed that the complementation of MRI to prenatal US did not differ from prenatal US in detecting orofacial clefts if the type of orofacial clefts was not distinguished. Subgroup analysis showed that the specificity of prenatal US for the detection of isolated cleft palate (CP) was lower than that of the complementation of MRI to prenatal US. Furthermore, network meta-analysis consistently suggested a comparable diagnostic value between prenatal US and the complementation of MRI to prenatal US. Moreover, subgroup analysis showed that the specificity of prenatal US was significantly lower than that of complementation of MRI to prenatal US for the detection of isolated CP. CONCLUSIONS: MRI is more accurate than ultrasound in detecting cleft palate. Therefore, MRI should be offered if there is a fetus with a possible or ultrasound diagnosis of cleft palate, especially if the evaluation of cleft palate is deemed unsatisfactory after careful evaluation of the images.
The construction of super large section (SLS) shallow buried tunnels involves challenges related to their large span, high flat rate, and complex construction process. Selecting an appropriate excavation method is crucial for ensuring stability, controlling costs, and managing the construction timeline. This study focuses on the selection of excavation methods and the mechanical responses of SLS tunnels in different types of surrounding rock. The research is based on the Yangjiashan tunnel project in Zhejiang Province, China, which is a four-line highway tunnel with a span of 21.3 m. Three sequential excavation methods were proposed and simulated using the three-dimensional finite difference method: the "upper first and lower later" side drift (SD) method, the central diaphragm method, and the top heading and bench (HB) method. The mechanical response characteristics of tunnel construction under these methods were investigated, including rock deformation, rock pressure, and the internal forces acting on the primary support. By comparing the performance of the three construction methods in rock masses of Grades III to V, the study aimed to determine the optimal construction method for SLS tunnels considering factors such as safety, cost, and schedule. Field tests were conducted to evaluate the effectiveness of the optimized construction scheme. The results of the field monitoring indicated that the "upper first and lower later" SD method in Grade V rock mass and the HB method in Grade III to IV rock mass are feasible and cost-effective under certain conditions. The research findings provide valuable insights for the design and construction of SLS tunnels in complex conditions, serving as a reference for engineers and project managers.
A mild and effective strategy for the asymmetric synthesis of C2-quaternary indolin-3-ones from 2-alkynyl arylazides and ketones by gold/chiral amine relay catalysis is described. In this reaction, 2-alkynyl arylazides undergo gold-catalyzed cyclization, nucleophilic attack, and oxidation to form intermediate 2-phenyl-3H-indol-3-ones, followed by an l-proline-catalyzed asymmetric Mannich reaction with ketones, to afford corresponding products in satisfactory yields with excellent enantio- and diastereoselectivities.
The pursuit of highly-active and stable catalysts in anodic oxygen evolution reaction (OER) is desirable for high-current-density water electrolysis toward industrial hydrogen production. Herein, a straightforward yet feasible method to prepare WFeRu ternary alloying catalyst on nickel foam is demonstrated, whereby the foreign W, Fe, and Ru metal atoms diffuse into the Ni foam resulting in the formation of inner immobilized ternary alloy. Thanks to the synergistic impact of foreign metal atoms and structural robustness of inner immobilized alloying catalyst, the well-designed WFeRu@NF self-standing anode exhibits superior OER activities. It only requires overpotentials of 245 and 346 mV to attain current densities of 20 and 500 mA cm-2 , respectively. Moreover, the as-prepared ternary alloying catalyst also exhibits a long-term stability at a high-current-density of 500 mA cm-2 for over 45 h, evidencing the inner-immobilization strategy is promising for the development of highly active and stable metal-based catalysts for high-density-current water oxidation process.
Integrating inorganic oxygen evolution cocatalysts (OECs) with photoanodes is regarded as an available strategy to increase the photogenerated charge utilization for accelerated water oxidation kinetics. Nevertheless, most widely used transition metal (oxyhydr)oxides OECs suffer from inevitable charge recombination at photoanode/OECs interfaces and underabundant catalytic active sites. Herein, a cobalt-organic complex with microflower-like features (denoted as MF) was constructed by coordination of Schiff base ligands and Co2+ metal ions and then decorated on porous BiVO4 employed as photoanodes for photoelectrochemical (PEC) water oxidation. The as-synthesized BiVO4/MF photoanode achieves a photocurrent density of 4.38 mA cm-2 and at 1.23 VRHE in 0.5 M Na2SO4 electrolyte under simulated 1 sun illumination, over approximately 5.48 times larger than that of BiVO4 counterpart, and exhibits a 120 mV cathodic shift of onset potential with outstanding photostability. Systematic characterizations reveal that the improved PEC efficiency is mainly attributed to the well-designed coordinatively unsaturated Co2+ sites, which not only serve as powerful photohole extraction engines along reversed interfacial Co-O-Bi bonds to promote charge transfer across the BiVO4/complex interface but also act as reaction active centers by accelerating surface water oxidation kinetics. This work provides new insights for designing highly effective OECs for PEC water oxidation.
The lack of available protons severely lowers the activity of alkaline hydrogen evolution reaction process than that in acids, which can be efficiently accelerated by tuning the coverage and chemical environment of protons on catalyst surface. However, the cycling of active sites by proton transfer is largely dependent on the utilization of noble metal catalysts because of the appealing electronic interaction between noble metal atoms and protons. Herein, an all-non-noble W/WO2 metallic heterostructure serving as an efficient solid-acid catalyst exhibits remarkable hydrogen evolution reaction performance with an ultra-low overpotential of -35 mV at -10 mA/cm2 and a small Tafel slope (-34 mV/dec), as well as long-term durability of hydrogen production (>50 h) at current densities of -10 and -50 mA/cm2 in alkaline electrolyte. Multiple in situ and ex situ spectroscopy characterizations combining with first-principle density functional theory calculations discover that a dynamic proton-concentrated surface can be constructed on W/WO2 solid-acid catalyst under ultra-low overpotentials, which enables W/WO2 catalyzing alkaline hydrogen production to follow a kinetically fast Volmer-Tafel pathway with two neighboring protons recombining into a hydrogen molecule. Our strategy of solid-acid catalyst and utilization of multiple spectroscopy characterizations may provide an interesting route for designing advanced all-non-noble catalytic system towards boosting hydrogen evolution reaction performance in alkaline electrolyte.
Staphylococcus aureus (S. aureus), as the main pathogen in milk and dairy products, usually causes intoxication with vomiting and various kinds of inflammation after entering the human body. CodY, an important transcriptional regulator in S. aureus, plays an important role in regulating metabolism, growth, and virulence. However, little is known about the role of CodY on environmental stress tolerance. In this research, we revealed the role of CodY in environmental stress tolerance in foodborne S. aureus RMSA24. codY mutation significantly reduced the tolerance of S. aureus to desiccation and oxidative, salt, and high-temperature stresses. However, S. aureus was more tolerant to low temperature stress due to mutation of codY. We found that the expressions of two important heat shock proteins-GroEL and DanJ-were significantly down-regulated in the mutant codY. This suggests that CodY may indirectly regulate the high- and low-temperature tolerance of S. aureus by regulating the expressions of groEL and danJ. This study reveals a new mechanism of environmental stress tolerance in S. aureus and provides new insights into controlling the contamination and harm caused by S. aureus in the food industry.
An asymmetric double oxidative [3 + 2] cycloaddition is reported. Oxidation of 3-((2,2,2-trifluoroethyl)amino)indolin-2-ones and ß-aryl-substituted aldehydes simultaneously and subsequent asymmetric cycloaddition in the presence of the chiral amino catalyst generated highly functionalized chiral CF3-containing spiro[pyrrolidin-3,2'-oxindole] with four contiguous stereocenters stereoselectively, which is characterized by directly constructing two C-C bonds from four C(sp3)-H bonds. This new method features mild conditions, broad substrate scope, and excellent functional group compatibility.
Staphylococcus aureus is one of the main microorganisms that contaminate dairy products and pickled foods, and has a great impact on economy and human health. GdmH-related proteins, as important functional units widely present in Staphylococcus species, have not been reported in S. aureus so far. In this study, we identified a gdmH-related gene, named ghl. We found that mutation of ghl gene could decrease the tolerance of environmental stresses (heat, desiccation, salt and hydrogen peroxide) of S. aureus and enhanced the capacities of biofilm formation. In addition, the ghl mutant was more sensitive to vancomycin on CAMHB solid plates but more resistant to vancomycin in CAMHB liquid medium compared to wild type RMSA24. These results indicated that ghl is an important factor to respond to environmental stress in foodborne S. aureus. This paper for the first time reported that a GdmH-related protein plays an important role in environmental tolerance, providing a new direction for the follow-up study of GdmH-related proteins, as well as a potential target gene for further research on the tolerance mechanism of Staphylococcus aureus in food processing and the control of biofilm formation.
Staphylococcus aureus , Vancomycin , Humans , Animals , Vancomycin/pharmacology , Staphylococcus aureus/genetics , Anti-Bacterial Agents/pharmacology , Milk , Follow-Up Studies
Avian pathogenic Escherichia coli (APEC) is one of the common extraintestinal infectious disease pathogens in chickens, geese, and other birds. It can cause a variety of infections, and even the death of poultry, causing enormous economic losses. However, the misuse and abuse of antibiotics in the poultry industry have led to the development of drug resistance in the gut microbes, posing a challenge for the treatment of APEC infections. It has been reported that the CpxRA two-component system has an effect on bacterial drug resistance, but the specific regulatory mechanism remains unclear. In this study, the regulatory mechanism of CpxRA on APEC biofilm formation and EmrKY efflux pump was investigated. The cpxRA knockout strain of E. coli APEC40 was constructed, and the molecular regulatory mechanism of CpxR on biofilms and efflux pump-coding genes were identified by biofilm formation assays, drug susceptibility test, real-time reverse transcription quantitative PCR, and electrophoretic mobility shift assay (EMSA). The results indicated that CpxR can directly bind to the promoter region of emrKY and negatively regulate the sensitivity of bacteria to ofloxacin and erythromycin. These results confirm the important regulatory role of the CpxRA two-component system under antibiotic stress in APEC.
α-(3-Indolyl)ketones are essential building blocks for the generation of biologically active molecules. We described a new method for the direct assembly of α-(3-indolyl)ketones through the cascade reaction of 2-alkynyl aryl azides with enecarbamates, in which the in situ generated α-imino gold carbene intermediate was trapped by enecarbamate to achieve umpolung reactivity of indole at the 3-position.
Staphylococcus aureus (S. aureus) is an opportunistic foodborne pathogen whose survival in food processing environments may be associated with its tolerance to desiccation. However, the molecular mechanisms involved in desiccation stress have received little attention in S. aureus. Here, some potential genes related to desiccation stress were determined in S. aureus by the transposon random mutagenesis approach. Eight mutants with different mutant sites who showed lower survival rates compared to wild-type (WT) strain RMSA24 under desiccation stress were successfully screened from a mutant library (n = 3,154). The eight mutation sites are identified as potential genes of U32 family peptidase, CHAP domain-containing protein, YdcF family protein, RNA polymerase sigma factor, EVE domain-containing protein, acetyltransferase, LPXTG-anchored DUF1542 repeat protein FmtB, and CvpA family protein, which haven't been reported as the desiccation-tolerant related genes. We found that the growth rates and biofilm formation abilities of these mutants were not significantly affected, indicating that their reduced survival rates under desiccation stress not dependent on reduced growth rates and biofilm formation abilities. Under desiccation stress, the expression levels of the three mutated genes were up-regulated and the four mutated genes were down-regulated in the WT strain, implying that these genes may play different roles in S. aureus to adapt to desiccation stress conditions. The study reveals valuable information for the control of S. aureus in low water activity foods and their production environments.
Desiccation , Staphylococcus aureus , Staphylococcus aureus/genetics , Staphylococcus aureus/metabolism , Mutagenesis, Insertional , Mutation
Tumors are one of the most common fatal diseases worldwide and pose a severe threat to human health. Effective tumor prevention and treatment strategies are persistent challenges in the medical community. Angiogenesis plays a critical role in and is the basis for tumor development and metastasis. Circular RNAs (circRNAs) are novel singlestranded covalently closed RNA molecules that are widely expressed in tumors due to their structural specificity and conservation. circRNAs affect angiogenesis by functioning as microRNA sponges to regulate vascular endothelial growth factorrelated pathways, thereby participating in various stages of tumor growth, invasion and proliferation. The present review summarizes the involvement of circRNAs in the regulation of tumor angiogenesis through competing endogenous RNA mechanisms, with a particular focus on the regulatory role of circRNAs in tumor angiogenesis in various systems. It is considered that circRNAs have great potential for use as tumor diagnostic markers and antiangiogenic therapies, and are thus worthy of further research and exploration.
MicroRNAs , Neoplasms , Humans , RNA, Circular/genetics , Vascular Endothelial Growth Factor A , MicroRNAs/genetics , MicroRNAs/metabolism , Neoplasms/genetics , Biomarkers, Tumor
Staphylococcus aureus (S. aureus) is a momentous factor affecting food safety. It can survive under long-term desiccation stress and contaminate foods that have intermediate to low water activities. However, the specific molecular mechanisms by which it survives and persists under low water activity stress are often overlooked. In this study, transcriptome analysis was applied to investigate the effect of desiccation stress on gene expression of S. aureus RMSA24, a food-borne S. aureus strain that was isolated from a raw milk sample. Results of transcriptome analysis showed that the mRNA levels of genes related to capsular polysaccharides (CPs) synthesis were significantly upregulated after desiccation treatment, which was further confirmed by real-time reverse transcription PCR assays. Furthermore, the results of colony count experiments demonstrated that the survival of CPs mutant was decreased compared with the wild type strain. And the biofilm formation ability of CPs mutant showed no difference compared with that of wild type according to biofilm formation assays. Those results indicated that CPs mutant decrease the resistance to desiccation in S. aureus RMSA24 via a biofilm-independent pathway. This study provides new evidence regarding the mechanisms of desiccation resistance of food-borne S. aureus and contributes to the prevention of food contamination caused by this bacterium.
Desiccation , Staphylococcus aureus , Gene Expression Profiling , Polysaccharides/pharmacology , Water
Handmade dairy products, which retain the nutrients in milk to the greatest extent, have become popular in China recently. However, no investigation regarding the characteristics of Staphylococcus aureus (S. aureus) in raw milk of handmade dairy retail stores has been reported. Here, we investigated the antimicrobial susceptibility, virulence, biofilm formation, and genetic diversity of S. aureus in raw milk from handmade dairy retail stores in Hefei, China. After 10 months of long-term monitoring, 50 S. aureus strains were isolated from 69 different raw milk samples, of which 6 were positive for methicillin-resistant S. aureus (MRSA). The resistance rates of these isolates to ampicillin, erythromycin, kanamycin, tetracycline, sulfamethoxazole-trimethoprim, gentamicin, ofloxacin, oxacillin, chloramphenicol, and doxycycline were 56, 54, 40, 24, 22, 22, 18, 14, 8 and 6%, respectively. All 50 isolates were susceptible to vancomycin and 29 strains (58%) showed multidrug resistance phenotype. For enterotoxins genes, selp (14%) was detected the most frequently, followed by sea (6%), sec (4%), sei (4%), ser (4%), selj (4%), and seh (2%). By microplate assay, 32 and 68% of the strains showed moderate and strong biofilm formation ability, respectively. Fifty isolates were discriminated into nine spa types, and the most common spa typing was t034 (42%). The results of this study indicate that S. aureus from raw milk may constitute a risk concerning food poisoning, and more attention must be given to awareness and hygienic measures in the food industry.
Efficient enantioselective separation using porous materials requires tailored and diverse pore environments to interact with chiral substrates; yet, current cage materials usually feature uniform pores. Herein, we report two porous assemblies, PCC-60 and PCC-67, using isostructural octahedral cages with intrinsic microporous cavities of 1.5 nm. The PCC-67 adopts a densely packed mode, while the PCC-60 is a hierarchically porous assembly featuring interconnected 2.4 nm mesopores. Compared with PCC-67, the PCC-60 demonstrates excellent enantioselectivity and recyclability in separating racemic diols and amides. This solid adsorbent PCC-60 is further utilized as a chiral stationary phase for high-performance liquid chromatography (HPLC), enabling the complete separation of six valuable pharmaceutical intermediates. According to quantitative dynamic experiments, the hierarchical pores facilitate the mass transfer within the superstructure, shortening the equilibrium time for adsorbing chiral substrates. Notably, this hierarchically porous material PCC-60 indicates remarkably higher enantiomeric excess (ee) values in separating racemates than PCC-67 with uniform microporous cavities. Control experiments confirm that the presence of mesopores enables the PCC-60 to separate bulky substrates. These results uncover the traditionally underestimated role of hierarchical porosity in porous-superstructure-based enantioseparation.
A chiral metal-organic framework (CMOF) with open chiral channels and multiple recognition sites is constructed from camphoric acid and a dipyridyl ligand. It can act as an efficient chiral solid adsorbent, capable of separating a variety of racemic alcohols and epoxides with excellent enantioselectivities.
Metal-Organic Frameworks , Zinc , Alcohols , Organic Chemicals , Stereoisomerism
Tungsten carbides, featured by their Pt-like electronic structure, have long been advocated as potential replacements for the benchmark Pt-group catalysts in hydrogen evolution reaction. However, tungsten-carbide catalysts usually exhibit poor alkaline HER performance because of the sluggish hydrogen desorption behavior and possible corrosion problem of tungsten atoms by the produced hydroxyl intermediates. Herein, we report the synthesis of tungsten atomic clusters anchored on P-doped carbon materials via a thermal-migration strategy using tungsten single atoms as the parent material, which is evidenced to have the most favorable Pt-like electronic structure by in-situ variable-temperature near ambient pressure X-ray photoelectron spectroscopy measurements. Accordingly, tungsten atomic clusters show markedly enhanced alkaline HER activity with an ultralow overpotential of 53 mV at 10 mA/cm2 and a Tafel slope as low as 38 mV/dec. These findings may provide a feasible route towards the rational design of atomic-cluster catalysts with high alkaline hydrogen evolution activity.
We describe a gold-catalyzed cyclization of 1-(2'-azidoaryl)propargylsulfonamides for the synthesis of 3-sulfonamidoquinolines, featuring a rare and highly selective 1,2-N migration. The key α-imino gold carbene intermediate is generated through an intramolecular nucleophilic attack of the azide group to the Au-activated triple bonds in a 6-endo-dig manner.
Ferroptosis, a new type of cell death, is mainly characterized by intracellular iron accumulation and lipid peroxidation. The complex regulatory network of iron metabolism, lipid metabolism, amino acid metabolism, p53-related signaling, and Nrf2-related signaling factors is involved in the entire process of ferroptosis. It has been reported that ferroptosis is involved in the pathogenesis of neurological diseases, cancer, and ischemia-reperfusion injury. Recent studies found that ferroptosis is closely related to the pathogenesis of COPD, which, to some extent, indicates that ferroptosis is a potential therapeutic target for COPD. This article mainly discusses the related mechanisms of ferroptosis, including metabolic regulation and signaling pathway regulation, with special attention to its role in the pathogenesis of COPD, aiming to provide safe and effective therapeutic targets for chronic airway inflammatory diseases.
