Mechanistic Studies of Stimulus-Response Integrated Catalysis of Single-Atom Alloys under Electric Fields for Electrochemical Nitrogen Reduction.

The present work introduces a novel catalytic strategy to promote the nitrogen reduction reaction (NRR) by employing a cooperative Cu-based single-atom alloy (SAA) and oriented external electric fields (OEEFs) as catalysts. The field strength (F)-dependent reaction pathways are investigated by means of first-principles calculations. Different dipole-induced responses of intermediates to electric fields break the original scaling relationships and effectively tune not only the activity but also the product selectivity of the NRR. When the most active Os1Cu SAA is taken as an example, in the absence of an OEEF, the overpotential (η) of the NRR is 0.62 V, which is even larger than that of the competitive hydrogen evolution reaction (HER). A negative field not only reduces η but switches the preference to the NRR over the HER. In particular, η at F = -1.14 V/Šreaches the bottom of 0.18 V, which is 70% lower than that in the field-free state.

Machine Learning Reveals Serum Glycopatterns as Potential Biomarkers for the Diagnosis of Nonalcoholic Fatty Liver Disease (NAFLD).

Nonalcoholic fatty liver disease (NAFLD) has emerged as the predominant chronic liver condition globally, and underdiagnosis is common, particularly in mild cases, attributed to the asymptomatic nature and traditional ultrasonography's limited sensitivity to detect early-stage steatosis. Consequently, patients may experience progressive liver pathology. The objective of this research is to ascertain the efficacy of serum glycan glycopatterns as a potential diagnostic biomarker, with a particular focus on the disease's early stages. We collected a total of 170 serum samples from volunteers with mild-NAFLD (Mild), severe-NAFLD (Severe), and non-NAFLD (None). Examination via lectin microarrays has uncovered pronounced disparities in serum glycopatterns identified by 19 distinct lectins. Following this, we employed four distinct machine learning algorithms to categorize the None, Mild, and Severe groups, drawing on the alterations observed in serum glycopatterns. The gradient boosting decision tree (GBDT) algorithm outperformed other models in diagnostic accuracy within the validation set, achieving an accuracy rate of 95% in differentiating the None group from the Mild group. Our research indicates that employing lectin microarrays to identify alterations in serum glycopatterns, when integrated with advanced machine learning algorithms, could constitute a promising approach for the diagnosis of NAFLD, with a special emphasis on its early detection.

The meso-substituent electronic effect of Fe porphyrins on the electrocatalytic CO2 reduction reaction.

We report Fe porphyrins bearing different meso-substituents for the electrocatalytic CO2 reduction reaction (CO2RR). By replacing two and four meso-phenyl groups of Fe tetraphenylporphyrin (FeTPP) with strong electron-withdrawing pentafluorophenyl groups, we synthesized FeF10TPP and FeF20TPP, respectively. We showed that FeTPP and FeF10TPP are active and selective for CO2-to-CO conversion in dimethylformamide with the former being more active, but FeF20TPP catalyzes hydrogen evolution rather than the CO2RR under the same conditions. Experimental and theoretical studies revealed that with more electron-withdrawing meso-substituents, the Fe center becomes electron-deficient and it becomes difficult for it to bind a CO2 molecule in its formal Fe0 state. This work is significant to illustrate the electronic effects of catalysts on binding and activating CO2 molecules and provide fundamental knowledge for the design of new CO2RR catalysts.

[Accumulation and biosynthesis mechanism of volatile oils in glandular scale of Agastache rugosa].

The volatile oils are the effective components of Agastache rugosa, which are stored in the glandular scale. The leaves of pulegone-type A. rugosa were used as materials to observe the leaf morphology of A. rugosa at different growth stages, and the components of volatile oils in gland scales were detected by GC-MS. At the same time, qRT-PCR was used to determine the relative expression of key enzyme genes in the biosynthesis pathway of monoterpenes in volatile oils. The results showed that the density of A. rugosa glandular scale decreased first and then tended to be stable. With the growth of leaves, the relative content of pulegone decreased from 79.26% to 3.94%(89.97%-41.44%), while that of isomenthone increased from 2.43% to 77.87%(0.74%-51.01%), and the changes of other components were relatively insignificant. The correlation analysis between the relative content of monoterpenes and the relative expression levels of their key enzyme genes showed that there was a significant correlation between the relative content of menthone and isomenthone and the relative expression levels of pulegone reductase(PR)(r>0.6, P<0.01). To sum up, this study revealed the accumulation rules of the main components of the contents of the glandular scale of A. rugosa and the expression rules of the key enzyme genes for biosynthesis, which provided a scientific basis and data support for determining the appropriate harvesting period and quality control of the medicinal herbs. This study also initially revealed the biosynthesis mechanism of the monoterpenes mainly composed of pulegone and isomenthone in A. rugosa, laying a foundation for further research on the molecular mechanism of synthesis and accumulation of monoterpenes in A. rugosa.

Downregulation of salusins alleviates hypertrophic cardiomyopathy via attenuating oxidative stress and autophagy.

INTRODUCTION: Salusins, which are translated from the alternatively spliced mRNA of torsin family 2 member A (TOR2A), play a vital role in regulation of various cardiovascular diseases. However, it remains unclear precisely regarding their roles in hypertrophic cardiomyopathy (HCM). Therefore, this study was conducted to explore therapeutic effect and the underlying mechanisms of salusins on HCM. MATERIAL AND METHODS: In vivo experiments, Sprague-Dawley rats were used to induce HCM model by angiotensin (Ang) II infusion for 4 weeks. The rats were randomly divided into four groups, namely, Saline + Control shRNA (n = 7), Ang II + Control shRNA (n = 8), Saline + TOR2A shRNA (n = 7), and Ang II + TOR2A shRNA groups (n = 8). After HCM induction, doppler echocardiography is recommended to evaluate heart function. In vitro experiments, primary neonatal rat cardiomyocytes (NRCMs) and cardiac fibroblasts (NRCFs) were obtained from newborn rats, and were treated with Ang II (10-6 M) for 24 h. RESULTS: After treatment with Ang II, levels of salusin-α and salusin-ß were elevated in serum and cardiac tissues of rats and in the neonatal rat cardiomyocytes and cardiac fibroblasts. Downregulation of salusins alleviated the Ang II-induced cardiac hypertrophy by suppressing the increased atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and beta-myosin heavy chain (ß-MHC) and cardiac fibrosis by blocking collagen I, collagen III and transforming growth factor-beta (TGF-ß), and it also attenuated oxidative stress by suppressing the increased reactive oxygen species (ROS) and malondialdehyde (MDA) levels and reversing the decreased superoxide dismutase (SOD) activity and autophagy by inhibiting the increased microtubule-associated protein light chain 3B (LC3B), Beclin1, autophagy related gene (Atg) 3 and Atg5 in the cardiac tissues of Ang II-infused rats and in the Ang II-treated NRCMs. CONCLUSIONS: All these findings suggest that the levels of salusins were elevated in the HCM, and targeting of salusins contributes to alleviation of cardiac hypertrophy and fibrosis probably via attenuating oxidative stress and autophagy. Accordingly, targeting of salusins may be a strategy for HCM therapy.

[Identification and analysis of terpene synthase (TPS) gene family in Schizonepeta tenuifolia].

Terpenoids are important secondary metabolites of plants that possess both pharmacological activity and economic value. Terpene synthases(TPSs) are key enzymes in the synthesis process of terpenoids. In order to investigate the TPS gene family members and their potential functions in Schizonepeta tenuifolia, this study conducted a systematic analysis of the TPS gene family of S. tenuifolia based on the whole genome data of S. tenuifolia using bioinformatics methods. The results revealed 57 StTPS members identified from the genome database of S. tenuifolia. The StTPS family members encoded 285-819 amino acids, with protein molecular weights ranging from 32.75 to 94.11 kDa, all of which were hydrophilic proteins. The StTPS family members were mainly distributed in the cytoplasm and chloroplasts, exhibiting a random and uneven physical localization pattern. Phylogenetic analysis showed that the StTPS genes family were divided into six subgroups, mainly belonging to the TPS-a and TPS-b subfamilies. Promoter analysis predicted that the TPS gene family members could respond to various stressors such as light, abscisic acid, and methyl jasmonate(MeJA). Transcriptome data analysis revealed that most of the TPS genes were expressed in the roots of S. tenuifolia, and qRT-PCR analysis was conducted on genes with high expression in leaves and low expression in roots. Through the analysis of the TPS gene family of S. tenuifolia, this study identified StTPS5, StTPS18, StTPS32, and StTPS45 as potential genes involved in sesquiterpene synthesis of S. tenuifolia. StTPS45 was cloned for the construction of an prokaryotic expression vector, providing a reference for further investigation of the function and role of the TPS gene family in sesquiterpene synthesis.

The glycopatterns of Pseudomonas aeruginosa as a potential biomarker for its carbapenem resistance.

IMPORTANCE: Bacterial surface glycans are an attractive therapeutic target in response to antibiotics; however, current knowledge of the corresponding mechanisms is rather limited. Antimicrobial susceptibility testing, genome sequencing, and MALDI-TOF MS, commonly used in recent years to analyze bacterial resistance, are unable to rapidly and efficiently establish associations between glycans and resistance. The discovery of new antimicrobial strategies still requires the introduction of promising analytical methods. In this study, we applied lectin microarray technology and a machine-learning model to screen for important glycan structures associated with carbapenem-resistant P. aeruginosa. This work highlights that specific glycopatterns can be important biomarkers associated with bacterial antibiotic resistance, which promises to provide a rapid entry point for exploring new resistance mechanisms in pathogens.

Construction of Naphthalene Diimide Derived Nanostructured Cathodes through Self-Assembly for High-Performance Sodium-Organic Batteries.

Organic nanostructured electrodes are very attractive for next-generation sodium-ion batteries. Their great advantages in improved electron and ion transport and more exposed redox-active sites would lead to a higher actual capacity and enhanced rate performance. However, facile and cost-effective methods for the fabrication of nanostructured organic electrodes are still highly challenging and very rare. In this work, we utilize a bioinspired self-assembly strategy to fabricate nanostructured cathodes based on a rationally designed N-hydroxy naphthalene imide sodium salt (NDI-ONa) for high-performance sodium-organic batteries. Such a well-organized nanostructure can greatly enhance both ion and electron transport. When used as cathode for sodium-organic batteries, it provides among the best battery performances, such as high capacity (171 mA h g-1 at 0.05 A g-1), excellent rate performance (153 mA h g-1 at 5.0 A g-1), and ultralong cycling life (93% capacity retention after 20000 cycles at 3.0 A g-1). Even at low temperature or without a conductive additive, it can also perform well. It is believed that self-assembly is a very powerful strategy to construct high-performance nanostructured electrodes.

Limited Song Mixing Without Genomic Gene Flow in a Contact Zone Between Two Songbird Species.

Song is considered to play an important role in the maintenance of prezygotic reproductive isolation between closely related songbird species. Therefore, song mixing in a contact zone between closely related species is often considered as evidence of hybridization. The Sichuan Leaf Warbler Phylloscopus forresti and the Gansu Leaf Warbler Phylloscopus kansuensis, which diverged 2 million years ago, have formed a contact zone in the south of the Gansu Province of China, where mixed songs have been observed. In this study, we investigated the potential causes and consequences of song mixing by integrating bioacoustic, morphological, mitochondrial, and genomic data with field ecological observations. We found that the two species display no apparent morphological differences, whereas their songs differ dramatically. We demonstrated that ∼11% of the males in the contact zone sang mixed songs. Two males singing mixed song were genotyped, and both were found to be P. kansuensis. Despite the presence of mixed singers, population genomic analyses detected no signs of recent gene flow between the two species, although two possible cases of mitochondrial introgression were identified. We conclude that the rather limited song mixing does not lead to, or result from, hybridization, and hence does not result in the breakdown of reproductive barriers between these cryptic species.

[Cloning of StHD1 and StHD8 from Schizonepeta tenuifolia and function of regulating glandular trichome development].

Hd-Zip, a unique transcription factor in plant kingdom, influences the growth, development, and secondary metabolism of plants. Hd-zip Ⅳ is thought to play an important role in trichome development of Schizonepeta tenuifolia. This study aims to explore the functions of StHD1 and StHD8 in Hd-zip Ⅳ subfamily in peltate glandular trichome development. To be specific, the expression patterns of the two genes and interaction between the proteins encoded by them were analyzed based on transcriptome sequencing and two-hybrid screening. The subcellular localization was performed and functions of the genes were verified in tobacco and S. tenuifolia. The results showed that StHD1 and StHD8 had high similarity to HD-Zip Ⅳ proteins of other plants and they all had the characteristic conserved domains of HD-Zip Ⅳ subfamily. They were located in the nucleus. The two genes mainly expressed in young tissues and spikes, and StHD1 and StHD8 proteins interacted with each other. The density and length of glandular trichomes increased significantly in tobacco plants with the overexpression of StHD1 and StHD8. Inhibiting the expression of StHD1 and StHD8 by VIGS(virus-induced gene silencing) in S. tenuifolia resulted in the reduction in the density of peltate glandular trichomes, the expression of key genes related to mono-terpene synthesis, and the relative content of limonene and pulegone, the main components of monoterpene. These results suggested that StHD1 and StHD8 of S. tenuifolia formed a complex to regulate glandular trichomes and affect the biosynthesis of monoterpenes.

Defective hBN-Supported Fe2N Single Cluster Catalyst for Active and Selective Electro-Reduction of Multiple CO to Propane: Theoretical Elucidation of Metal-Nonmetal Synergic Effects.

The present work introduces the multiple CO reduction toward C3 products promoted by a newly designed single cluster catalyst consisting of defective hBN and embedded dimerized Fe, by means of density functional theory calculations. We find the strong metal-support interactions give rise to the local strain and electron accumulation of the N coordinated with two metals and resultantly form a Fe2N active center. The metal-nonmetal synergic effect facilitates the coadsorption and C-C coupling of triple CO molecules and finally generates propane in a highly active and selective way.

An Important Role of the Type VI Secretion System of Pseudomonas aeruginosa Regulated by Dnr in Response to Anaerobic Environments.

The type VI secretion system (T6SS) is capable of secreting a variety of metal-binding proteins involved in metal ion uptake, and it mediates an active metal ion transport system that contributes to competition between bacteria. Pseudomonas aeruginosa H2-T6SS can increase molybdenum ion acquisition and enhance bacterial survival advantage by promoting the secretion of the molybdate-binding protein ModA, in which the expression of H2-T6SS core genes hcp2, hsiA2, and clpV2 is activated by anaerobic conditions and are all regulated by the global regulator Anr. Here, we report the regulation of T6SS by Dnr, a dedicated dissimilatory nitrate respiration regulator in P. aeruginosa. Of the three distinct T6SS loci carried by P. aeruginosa, only the anaerobic expression of H2-T6SS was activated by Dnr; H1-T6SS or H3-T6SS did not respond to anaerobically induced activation. We also demonstrated that Dnr promotes the anaerobic secretion of ModA, which acts as a potential substrate for H2-T6SS, providing an advantage not only for the anaerobic growth of bacteria but also for functional competition. Overall, this study elucidates the important role played by Dnr in mediating the anaerobic expression of T6SS in P. aeruginosa, indicating that the functional advantage of H2-T6SS in response to anaerobic induction may be a conditional environmental adaptation. It also extends our understanding of the function of Dnr as a specific regulator of dissimilatory nitrate respiration. IMPORTANCE The type VI secretion system (T6SS) plays an important role in bacterial competition by mediating the transport of active metal ions. Pseudomonas aeruginosa carries three distinct T6SS loci (H1-, H2-, and H3-T6SS). The H2-T6SS promotes the secretion of the molybdate-binding protein ModA for the acquisition of molybdenum ions to adapt to anaerobic survival. Here, we report that the specialized dissimilatory nitrate respiration regulator Dnr in P. aeruginosa controls the anaerobic expression of H2-T6SS and that this regulation is essential for ModA protein secretion, anaerobic growth, and bacterial competition. This study elucidates the regulatory mechanism of Dnr on H2-T6SS in P. aeruginosa, revealing an important role played by H2-T6SS in adapting to an anaerobic environment.

Nitrogen Electroreduction on Borophene-Supported Atomic and Diatomic Transition Metals: Stability, Activity and Selectivity Improvements via Defect-Engineering.

The present work investigated the binding of atomically dispersed transition metals to the perfect and single/double vacancy (SV/DV)-containing defective ß12 -borophenes and the catalytic performance of those corresponding single-atom catalysts (SACs) and diatomic catalysts (DACs) for nitrogen reduction reaction (NRR) by means of density functional theory calculations. Although previous theoretical studies proposed that the inherent hexagon hole of the defect-free ß12 -borophene is capable of anchoring single metal atom for NRR, calculations suggested that the interaction between borophene and doped metal is not strong enough to avoid metal aggregation. For the defective ß12 -borophene with SV, even though the single metal could be stabilized in an 8-membered ring, it was found that the SAC was still ineffective for NRR because of the competitive hydrogen evolution process. Regarding the DV-containing ß12 -borophene, a defective configuration with an unexpected 11-membered hole was proved as the most stable structure, which possessed a very similar average atomic energy (6.25 eV atom-1 ) compared to that of the pristine ß12 sheet (6.26 eV atom-1 ). Two metal atoms could be encapsulated into the confined space of the B11 ring. Compared to SACs, those corresponding DACs were more active for N2 fixation and hydrogenation, and the hydrogen evolution reaction could be passivated, attributing to the synergistic effect of dual metal centres. Among all candidates, the V2 /ß12 -DV was predicted as the most promising catalyst for NRR, with the limiting potential of as low as -0.15 V.

Autoimmune glial fibrillary acidic protein astrocytopathy presented as isolated area postrema symdrome: a case report.

BACKGROUND: Area postrema syndrome (APS) as the isolated manifestation in autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy has been rarely reported. CASE PRESENTATION: A 61-year-old male patient presented with intractable hiccup. He was first admitted to the department of Gastroenterology because he had no symptoms other than hiccup. Then he was diagnosed with possible digestive system disease and started on treatment. 2 weeks later, his symptom didn't improve at all. After consultation, the patient was referred to our department. Cerebrospinal fluid (CSF) analysis revealed lymphocytes pleocytosis, elevated protein level. Cell-based assays demonstrated GFAP antibodies in blood and CSF. His symptom improved with steroid pulse therapy (methylprednisolone, 1 g for 5 days), followed by a gradual tapering of oral prednisolone. Three months after the initial presentation, he showed no relapses. CONCLUSIONS: We report atypical manifestation of autoimmune GFAP astrocytopathy which presented as APS, suggesting that autoimmune GFAP astrocytopathy should be added to the list of possible cause of APS.

Evaluation of Shear and Peel Strength of Al1060 Single-Lap and T-Lap Joints Produced by Rotated Clinching Process with Twin Rotating Punches.

The clinching process is widely used in joining lightweight sheet metal. We proposed a novel rotated clinching process (RCP), which is characterized by a flat bottom die structure and twin rotating punches. The aim of this study was to evaluate the strength of RCP joints. Al1060 sheets with thicknesses of 1.5 mm and 2 mm were used as the experimental materials. Overlap and T-lap RCP joints with three die depths and five bottom thicknesses were fabricated, and shear and peel tests were performed on the joints. The joint strengths were evaluated based on the mechanical load, cross-sectional profile dimensions, and failure mode. The results showed that the mechanical load is a direct, reliable, and quantitative evaluation criterion, while the cross-sectional profile and failure mode are indirect and qualitative. These criteria confirmed that the strength of thick sheet joints is higher than that of thin sheet joints, the shear strength is superior to the peel strength, and the strengths of the joints are high with failure mainly occurring due to tearing or shear failure. Finally, the key parameters for determining the strength of a joint include the bottom thickness/sheet thickness ratio (Rt), and the die depth (h).

A novel NOTCH3 mutation and its clinical, neuroimaging and pathological presentation in a Chinese patient with CADASIL: A case report.

RATIONALE: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common form of familial cerebral small vessel disease in adults, and is caused by NOTCH3 mutations. However, individual symptom types, onset, and disease severity span a wide range. PATIENT CONCERNS: Herein, we report a case of chronic neurological symptoms including slurring of speech, recurrent weakness in both limbs and legs, and progressive memory loss. Cranial magnetic resonance imaging revealed recurrent acute lacunar subcortical infarction and extensive white matter hyperintensities. Skin biopsy revealed granular osmiophilic materials close to the cell surface of smooth muscle cells in an arteriolar vessel. The patient's genomic DNA showed a mutation c.635G>C[p.(Cys212Ser)] in exon 4. DIAGNOSIS: The patient was finally diagnosed with CADASIL. INTERVENTIONS: The patient was treated with antiplatelet therapy and extremity rehabilitation. OUTCOMES: There was no improvement in speech, extremity function, or memory. LESSONS: Accurate early diagnosis and appropriate treatment are crucial to improve the prognosis of patients with CADASIL.

A Prenatal Ultrasound Scanning Approach: One-Touch Technique in Second and Third Trimesters.

This study was aimed at evaluating the performance of the innovative technique Smart Fetus (SF) developed to recognize the planes and obtain the basic biometric measurements of fetuses automatically. This prospective study included 1005 uncomplicated singleton pregnancies undergoing routine examinations. For every pregnancy, planes, including the transverse section of the thalami, transverse section of the abdomen and longitudinal section of the femur, were acquired, and standard biometric measurements, including biparietal diameter, head circumference, abdominal circumference and femur length, were obtained using SF and traditional ultrasound technique (TUT). The accuracy, reproducibility and time required for the analysis of SF were compared with those of TUT. In 998 of 1005 cases (99.30%), SF successfully acquired the sections and made all measurements. The agreement between the techniques was high for all measurements. The time to obtain sections and measure biometric parameters or solely measure biometric parameters was significantly shorter with SF than with TUT. No significant differences were found in SF repeated measurements obtained by two independent observers. The SF technique helped in the acquisition of reliable standard sections and biometric measurements and saved time. It might serve as a novel ultrasound scanning approach and improve workflow efficiency.

Pseudomonas aeruginosa T6SS-mediated molybdate transport contributes to bacterial competition during anaerobiosis.

Type VI secretion system (T6SS) is widely distributed in Gram-negative bacteria and functions as a versatile protein export machinery that translocates effectors into eukaryotic or prokaryotic target cells. Growing evidence indicates that T6SS can deliver several effectors to promote bacterial survival in harmful environments through metal ion acquisition. Here, we report that the Pseudomonas aeruginosa H2-T6SS mediates molybdate (MoO42-) acquisition by secretion of a molybdate-binding protein, ModA. The expression of H2-T6SS genes is activated by the master regulator Anr and anaerobiosis. We also identified a ModA-binding protein, IcmP, an insulin-cleaving metalloproteinase outer membrane protein. The T6SS-ModA-IcmP system provides P. aeruginosa with a growth advantage in bacterial competition under anaerobic conditions and plays an important role in bacterial virulence. Overall, this study clarifies the role of T6SS in secretion of an anion-binding protein, emphasizing the fundamental importance of this bacterium using T6SS-mediated molybdate uptake to adapt to complex environmental conditions.

Structural characteristics of polysaccharide microcapsules fromNostoc commune,and their applications in skin wound healing and pathological repair.

In this study, the extraction conditions ofNostoc communeVauch polysaccharide (NCVP) were optimized by single factor and orthogonal experiments. Then, the NCVP microcapsules (NCVPM) were prepared. After analyzing the microcapsule structural and thermal characteristics, the skin wound healing ability was studied by establishing back trauma rat models. Results showed that the NCVP yield was 10.37% under the following optimum conditions: 210 min extraction time, solid-liquid ratio of 1:50 and extraction temperature of 90 °C. The overall performance of the microcapsule was the best when the concentration of sodium alginate, calcium chloride and chitosan was 2%, 3% and 0.3%, respectively. NCVPM had spherical morphology, typical microcapsule structural characteristics and good thermal stability, and NCVP was dispersed in the microcapsules. NCVPM showed good biocompatibility and biodegradability, which met the requirements for slow-release polymer materials. After 14 days of treatment, the wound healing rate was 92.4%, the cells were arranged neatly and regularly, the cell nucleus became large and elliptical, the cell had a tendency to divide, and the fibers and microvessel were significantly more. By evaluating the mechanism, NCVPM could increase the content of hydroxyproline and glutathione to protect cells from oxidative damage, leading in turn to accelerated wound healing and shorter wound healing times. It could also accelerate cell division, collagen and microvascular production by increasing transcription levels of vascular endothelial growth factor mRNA and miRNA-21.