Improving the mechanical property of silk by feeding silkworm with chiral carbon dots.

The influence of chiral materials on organisms is crucial. However, there is little research on the impact of chiral carbon dots (CDs), a kind of typical chiral materials, on biology. Herein, chiral CDs (L-/D-CDs) were synthesized using the thermal polymerization method from citric acid and chiral cysteine. The effect of chiral CDs on silkworms was explored through feeding silkworms with chiral CDs. The breaking strength of silk fibers (667.9 MPa) in D-CDs group exhibit a 71.4 % increase compared with control-silk (389.5 MPa), while the breaking strength of silk fibers in L-CDs group increases by 51.6 %. In addition, Fourier transform infrared spectra display CDs can prevent the transformation from random coil/α-helix structures to ß-sheet structures. Furthermore, D-CDs group exhibit the highest percentage of four primary amino acids (glycine, alanine, serine, and tyrosine) relative to the total amino acids in silkworm hemolymph. This percentage is elevated by 70.5 % compared to the control group, thereby furnishing an ample supply of raw materials for the synthesis of silk proteins. In contrast, L-CDs group exhibit increase by 39.3 %. Our work provides new ideas and approaches for studying the effects of chiral materials on living organisms.

Nobiletin, an activator of the pyruvate kinase isozyme M1/M2 protein, upregulated the glycolytic signalling pathway and alleviated depressive-like behaviour caused by artificial light exposure at night in zebrafish.

We established a zebrafish model of depression-like behaviour induced by exposure to artificial light at night (ALAN) and found that nobiletin (NOB) alleviated depression-like behaviour. Subsequently, based on the results of a 24-h free movement assay, clock gene expression and brain tissue transcriptome sequencing, the glycolysis signalling pathway was identified as a potential target through which NOB exerted antidepressant effects. Using the ALAN zebrafish model, we found that supplementation with exogenous L-lactic acid alleviated depressive-like behaviour. Molecular docking and molecular dynamics simulations revealed an inter-molecular interaction between NOB and the pyruvate kinase isozyme M1/M2 (PKM2) protein. We then used compound 3 k to construct a zebrafish model in which PKM2 was inhibited. Our analysis of this model suggested that NOB alleviated depression-like behaviour via inhibition of PKM2. In summary, NOB alleviated depressive-like behaviour induced by ALAN in zebrafish via targeting of PKM2 and activation of the glycolytic signalling pathway.

A metal-free cascaded process for efficient H2O2 photoproduction using conjugated carbonyl sites.

Carbon-based metal-free catalysts are promising green catalysts for photocatalysis and electrocatalysis due to their low cost and environmental friendliness. A key challenge in utilizing these catalysts is identifying their active sites, given their poor crystallinity and complex structures. Here we demonstrate the key structure of the double-bonded conjugated carbon group as a metal-free active site, enabling efficient O2 photoreduction to H2O2 through a cascaded water oxidation - O2 reduction process. Using ethylenediaminetetraacetic acid as a precursor, we synthesized various carbon-based photocatalysts and analyzed their structural evolution. Under the polymerization conditions of 260 °C to 400 °C, an N-ethyl-2-piperazinone-like structure was formed on the surface of the catalyst, resulting in high photocatalytic H2O2 photoproduction (2884.7 µmol g-1h-1) under visible light. A series of control experiments and theoretical calculations further confirm that the double-bond conjugated carbonyl structure is the key and universal feature of the active site of metal-free photocatalysts.

Highly selective conversion of carbon dioxide to methane by copper single atom electrocatalysts.

Electrocatalytic carbon dioxide (CO2) reduction into high-value chemicals is one of the important solutions to the greenhouse effect and energy crisis. However, the slow kinetic process of eight electrons requires the development of efficient catalysts to improve the yields. Single atom catalysts (SACs) with high activity and selectivity have become an emerging research frontier in the field of heterogeneous catalysis. Herein, a catalyst comprised of Cu single atoms loaded on carbon substrate (Cu-NC) is developed for highly selective electrocatalytic reduction of CO2 to methane (CH4). The optimal catalyst (Cu-NC-1-4) exhibits a faradaic efficiency (FE) of over 50% for CH4 within a wide potential window from -1.3 V to -1.8 V (vs. RHE) and the highest FE of CH4 is up to 67.22% at -1.6 V (vs. RHE). Meanwhile, the product selectivity of CH4 among all the carbon products reaches 93.00%, and the activity decay can be negligible via the 70-hour-stability-test. The existence of atomic dispersed Cu-N3 sites was verified by high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) and X-ray absorption near edge structure (XANES). Density functional theory (DFT) calculations show that the effective adsorption of the key intermediate *CO on Cu-N3 sites prompts the generation of CH4.

External validation of the iScore, ASTRAL score, DRAGON score, and THRIVE score and development of a nomogram to predict outcome in patients with large vessel occlusion-acute ischemic stroke.

OBJECTIVE: This study aimed to validate the iScore, ASTRAL score, DRAGON score, and THRIVE score for assessing large vessel occlusion-acute ischemic stroke (AIS-LVO) and establish a predictive model for AIS-LVO patients that has better performance to guide clinical practice. METHODS: We retrospectively included 439 patients with AIS-LVO and collected baseline data from all of them. External validation of the iScore, ASTRAL score, DRAGON score, and THRIVE score was performed. All variables were compared between groups via univariate analysis, and the results are expressed as ORs and 95 % CIs. Independent variables with P < 0.25 were included in the multivariate logistic analysis, and statistically significant differences (P < 0.05) were identified as risk factors for prognosis in AIS-LVO patients. Receiver operating characteristic (ROC) curve analysis and decision curve analysis (DCA) were used to evaluate the predictive value of our model. RESULTS: Our external validation resulted in an iScore under the curve (AUC) of 0.8475, an ASTRAL AUC of 0.8324, a DRAGON AUC of 0.8196, and a THRIVE AUC of 0.8039. In our research, multivariate Cox regression revealed 8 independent predictors. We used a nomogram to visualize the results of the data analysis. The AUC for the training cohort was 0.8855 (95 % CI, 0.8487-0.9222), and that in the validation cohort was 0.8992 (95 % CI, 0.8496-0. 9488). CONCLUSIONS: In this study, we verified that the above scores have excellent efficacy in predicting the prognosis of AIS-LVO patients. The nomogram we developed was able to predict the prognosis of AIS-LVO more accurately and may contribute to personalized clinical decision-making and treatment for future clinical work.

Environmentally degradable carbon dots for inhibiting P. globosa growth and reducing hemolytic toxin.

Red tides not only destroy marine ecosystems but also pose a great threat to human health. The traditional anti-red tide materials are difficult to degrade effectively in the natural environment and there may be risks of environmental leakage and secondary pollution. Furthermore, they cannot reduce the toxicity of toxins released by algae. It is very important to prepare degradable materials that can effectively control red tide and reduce their toxins in the future. Herein, degradable CDs (De-CDs) with biocompatibility and non-toxicity is successfully prepared using the one-step electrolytic method. De-CDs can effectively inhibit P. globosa (algae associated with red tide) growth. More importantly, the De-CDs not only can attenuate the toxicity of toxins released by P. globosa, but also can be degraded under visible-light irradiation in the seawater and avoids environmental leakage. The successful preparation of De-CDs provides a new idea for degradable materials with anti-red tide algae in the future.

Unveiling the causal link between metabolic factors and ovarian cancer risk using Mendelian randomization analysis.

Background: Metabolic abnormalities are closely tied to the development of ovarian cancer (OC), yet the relationship between anthropometric indicators as risk indicators for metabolic abnormalities and OC lacks consistency. Method: The Mendelian randomization (MR) approach is a widely used methodology for determining causal relationships. Our study employed summary statistics from the genome-wide association studies (GWAS), and we used inverse variance weighting (IVW) together with MR-Egger and weighted median (WM) supplementary analyses to assess causal relationships between exposure and outcome. Furthermore, additional sensitivity studies, such as leave-one-out analyses and MR-PRESSO were used to assess the stability of the associations. Result: The IVW findings demonstrated a causal associations between 10 metabolic factors and an increased risk of OC. Including "Basal metabolic rate" (OR= 1.24, P= 6.86×10-4); "Body fat percentage" (OR= 1.22, P= 8.20×10-3); "Hip circumference" (OR= 1.20, P= 5.92×10-4); "Trunk fat mass" (OR= 1.15, P= 1.03×10-2); "Trunk fat percentage" (OR= 1.25, P= 8.55×10-4); "Waist circumference" (OR= 1.23, P= 3.28×10-3); "Weight" (OR= 1.21, P= 9.82×10-4); "Whole body fat mass" (OR= 1.21, P= 4.90×10-4); "Whole body fat-free mass" (OR= 1.19, P= 4.11×10-3) and "Whole body water mass" (OR= 1.21, P= 1.85×10-3). Conclusion: Several metabolic markers linked to altered fat accumulation and distribution are significantly associated with an increased risk of OC.

Adaptive functions of structural variants in human brain development.

Quantifying the structural variants (SVs) in nonhuman primates could provide a niche to clarify the genetic backgrounds underlying human-specific traits, but such resource is largely lacking. Here, we report an accurate SV map in a population of 562 rhesus macaques, verified by in-house benchmarks of eight macaque genomes with long-read sequencing and another one with genome assembly. This map indicates stronger selective constrains on inversions at regulatory regions, suggesting a strategy for prioritizing them with the most important functions. Accordingly, we identified 75 human-specific inversions and prioritized them. The top-ranked inversions have substantially shaped the human transcriptome, through their dual effects of reconfiguring the ancestral genomic architecture and introducing regional mutation hotspots at the inverted regions. As a proof of concept, we linked APCDD1, located on one of these inversions and down-regulated specifically in humans, to neuronal maturation and cognitive ability. We thus highlight inversions in shaping the human uniqueness in brain development.

Enantioselective and Band-Gap Modulation in Photocatalysis of Metal-Free Chiral Carbon Dots.

Photodriven chiral catalysis is the combination of photocatalysis and chiral catalysis and is considered one of the cleanest and most efficient methods for the synthesis of chiral compounds or drugs. Furthermore, due to the potential metal contamination associated with most metal-based catalysts, metal-free chiral photocatalysts are ideal candidates. In this work, we demonstrate that metal-free chiral carbon dots (CDs) exhibit size-dependent enantioselective photocatalytic activity. Using serine as the raw material, chiral CDs with well-defined structures and average sizes of 2.22, 3.01, 3.70, 4.77, and 7.21 nm were synthesized using the electrochemical method. These chiral CDs possess size-dependent band gaps and exhibit photoresponsive enantioselective catalytic activity toward the oxidation of dihydroxyphenylalanine (DOPA). Under light-assisted conditions, chiral CDs (L72, 500 µg/mL) exhibit high selectivity (selectivity factor: 2.07) and maintain a certain level of catalytic activity (1.34 µM/min) even at a low temperature of 5 °C. The high catalytic activity of the chiral CDs arises from their photoelectrons reducing O2 to generate O2-, as the active oxygen species for DOPA oxidation. The high enantioselectivity of the chiral CDs is attributed to their differential adsorption capabilities toward DOPA enantiomers. This study provides a new approach for designing metal-free chiral photocatalysts with high enantioselectivity.

The Tao Hong Si Wu Decoction ameliorates diabetes-associated cognitive dysfunction by inhibiting the formation of amyloid plaques.

OBJECTIVES: The herbs in Tao Hong Si Wu Decoction (THSWD) are beneficial in the treatment of cognitive impairment. However, the underlying mechanisms of THSWD in treating diabetes-associated cognitive dysfunction (DACD) are not entirely explored. This study is aimed to investigate the therapeutic effects of THSWD in DACD model rats and the underlying mechanism. METHODS: Ultra-high-phase liquid chromatography was employed to identify the main compounds contained in the THSWD extract. DACD rat model was induced by feeding with a high-sugar and high-fat diet and injecting streptozotocin (35 mg/kg). DACD rats were gavaged with THSWD for 1 week. The learning and memory abilities of the rats were measured by using the Morris water maze. Western blotting was used to detect the changes in DACD rat targets. Statistical methods were used to evaluate the correlation between proteins. RESULTS: The results show that THSWD effectively reduced the escape latency, hippocampal neuron damage, glycosylated hemoglobin, type A1C, and blood lipid levels in DACD rats. Furthermore, DACD rats showed significantly increased amyloid precursor protein, ß-secretase, Aß1-40 , Aß1-42 , Tau phosphorylation, and advanced glycation end products (AGEs) expression. However, THSWD treatment can reverse this phenomenon. CONCLUSIONS: THSWD can improve the learning and memory abilities of DACD rats by inhibiting the expression of AEGs-AGE receptors pathway, which provides an experimental basis for the clinical application of THSWD. In addition, the experiment combines pharmacological and statistical methods, which offers a new perspective for the study of Chinese herbal medicine.

Carbon dots derived from metformin by electrochemical synthesis with broad-spectrum antibacterial properties.

Due to the advantages of good aqueous dispersion and biocompatibility, carbon dots (CDs) are promising candidates for a wide range of applications in the biological field. Notably, CDs derived from biosafe organic precursors will contribute both new types of CDs and new bioactivities. Herein, metformin (MET), a first-line drug for the treatment of type II diabetes, was selected as an organic precursor to fabricate a new type of CDs, namely, semi-carbonized MET (MCDs). These MCDs derived from MET possess a completely new antibacterial activity against Staphylococcus aureus (SA) and Escherichia coli (E. coli) compared with that of MET and achieve complete antibacterial activity at 200 µg mL-1. The broad-spectrum antibacterial mechanism of MCDs involves two aspects. For the Gram-positive bacteria SA, MCDs mainly affect the transport of nutrients by adsorbing onto the surface of bacteria, thereby inhibiting bacterial growth. For the Gram-negative bacteria E. coli, MCDs can easily pass through their thin cell walls and stimulate the bacteria to produce excess ROS, eventually leading to the death of the bacteria. This work may open a new way for the future design and development of CDs prepared from biosafe organic precursors with specific functions.

Enhanced the intrinsic oxidase-like activity of chiral carbon dots via manganese doping for selective catalytic oxidation.

It is highly desirable to design and construct chemical catalysts with high activity and specificity as the alternatives of natural enzymes for industrial application. Chiral carbon dots (CDs), possessing both the intrinsic enzyme-like activity and specific recognition ability, are one of good candidates for enzyme-like catalysts. However, their catalytic activity is far from that of natural enzymes and needs to be enhanced. In this work, the modulation of the chiral structure and catalytic activity of chiral CDs with intrinsic oxidase-like activity was implemented by manganese (Mn) doping. Under the light condition, chiral CDs (l-Ser-CDs and d-Ser-CDs) derived from chiral serine (Ser) show weak catalytic activity and low selectivity toward the oxidation of L type of dopamine (l-DOPA), whereas the Mn functionalized chiral CDs (l-Mn-CDs or d-Mn-CDs) exhibit 6.9 times higher in catalytic activity and 2.9 times in selectivity ratio (SR) than Ser-CDs. Mn-CDs involve two-path catalytic process, in which the photogenerated electrons could reduce O2 to O2- as the active species and the holes would oxidize DOPA directly. Moreover, doping of Mn enables the CDs to generate more O2-. Besides, l-Mn-CDs have higher catalytic activity than that of d-Mn-CDs (+54.2 %), and the chiral Mn-CDs have stronger selective adsorption capacity towards chiral DOPA than Ser-CDs. Our work provides a new method for designing and preparing novel chiral artificial enzymes.

27-Hydroxycholesterol inhibits trophoblast fusion during placenta development by activating PI3K/AKT/mTOR signaling pathway.

Trophoblast cell syncytialization is essential for placental and fetal development. Abnormal trophoblast cell fusion leads to pregnancy pathologies, such as preeclampsia (PE), intrauterine growth restriction (IUGR), and miscarriage. 27-hydroxycholesterol (27-OHC) is the most abundant oxysterol in human peripheral blood synthesized by sterol 27-hydroxylase (CYP27A1) and is considered a critical mediator between hypercholesterolemia and a variety of related disorders. Gestational hypercholesterolemia was associated with spontaneous preterm delivery and low birth weight (LBW) in term infants, yet the mechanism is unclear. In this study, two trophoblast cell models and CD-1 mice were used to evaluate the effects of 27-OHC on trophoblast fusion during placenta development. Two different kinds of trophoblast cells received a dosage of 2.5, 5, or 10 uM 27-OHC. Three groups of pregnant mice were randomly assigned: control, full treatment (E0.5-E17.5), or late treatment (E13.5-E17.5). All mice received daily intraperitoneal injections of saline (control group) and 27-OHC (treatment group; 5.5 mg/kg). In vitro experiments, we found that 27-OHC inhibited trophoblast cell fusion in primary human trophoblasts (PHT) and forskolin (FSK)-induced BeWo cells. 27-OHC up-regulated the expression of the PI3K/AKT/mTOR signaling pathway-related proteins. Moreover, the PI3K inhibitor LY294002 rescued the inhibitory effect of 27-OHC. Inhibition of trophoblast cell fusion by 27-OHC was also observed in CD-1 mice. Furthermore, fetal weight and placental efficiency decreased and fetal blood vessel development was inhibited in pregnant mice treated with 27-OHC. This study was the first to prove that 27-OHC inhibits trophoblast cell fusion by Activating PI3K/AKT/mTOR signaling pathway. This study reveals a novel mechanism by which dyslipidemia during pregnancy results in adverse pregnancy outcomes.

Metagenomic next-generation sequencing for diagnosis of infectious encephalitis and meningitis: a retrospective study of 90 patients.

BACKGROUND: Infections of the central nervous system (CNS) are potentially life-threatening and can cause serious morbidity. We evaluated the clinical value of metagenomic next-generation sequencing (mNGS) in the diagnosis of infectious encephalitis and meningitis and explored the factors affecting the results of mNGS. METHODS: Patients with suspected cases of encephalitis or meningitis who presented in Northern Jiangsu People's Hospital from 1 March 2018 to 30 September 2022 were collected. Demographic, historical, and clinical information were obtained, and cerebrospinal fluid (CSF) samples were treated with mNGS. The pathogen was identified using National Center for Biotechnology Information (NCBI) GenBank sequence data. RESULTS: Ninety-six patients were screened and finally 90 subjects enrolled. Of the 90 enrolled cases, 67 (74.4%) were diagnosed with central nervous system infections, which included 48 cases (71.6%) of viral infection, 11 (12.2%) of bacterial infection, 5 (7.5%) of mycobacterium tuberculosis, 2 (3.0%) of fungal infection, and 1 (1.5%) of rickettsia infection. From these cases, mNGS identified 40 (44.4%) true-positive cases, 3 (3.3%) false-positive case, 22 (24.4%) true-negative cases, and 25 (27.8%) false-negative cases. The sensitivity and specificity of mNGS were 61.5% and 88%, respectively. mNGS of CSF could show a higher positive rate in patients with marked CSF abnormalities, including elevated protein concentrations and monocyte counts. CONCLUSION: mNGS of CSF is an effective method for detecting infectious encephalitis and meningitis, and the results should be analyzed combined with conventional microbiological testing results.

Assessing causal associations of hyperparathyroidism with blood counts and biochemical indicators: a Mendelian randomization study.

Background: The existing literature on the relationship of hyperparathyroidism with both blood counts and biochemical indicators primarily comprises observational studies, which have produced inconsistent findings. This study aimed to evaluate the causal relationship between hyperparathyroidism and blood counts and biochemical indicators. Methods: Mendelian randomization (MR) analyses were conducted to investigate the associations between hyperparathyroidism and the identified 55 blood counts and biochemical indicators. The genome-wide association study (GWAS) for hyperparathyroidism data was obtained from FinnGen, while the GWASs for the blood counts and biochemical indicators were sourced from the UK Biobank (UKBB). Results: The MR analysis using the inverse-variance weighted (IVW) method revealed potential causality between genetically predicted hyperparathyroidism and seven out of 55 blood counts and biochemical indicators. These markers include "Platelet count" (Beta = -0.041; 95% CI: -0.066, -0.016; p = 0.001), "Platelet distribution width (PDW)" (Beta = 0.031; 95% CI: 0.006, 0.056; p = 0.016), "Mean platelet volume (MPV)" (Beta = 0.043; 95% CI: 0.010, 0.076; p = 0.011), "Vitamin D" (Beta = -0.038; 95% CI: -0.063, -0.013; p = 0.003), "Calcium (Ca2+)" (Beta = 0.266; 95% CI: 0.022, 0.509; p = 0.033), "Phosphate" (Beta = -0.114; 95% CI: -0.214, -0.014; p = 0.025), and "Alkaline phosphatase (ALP)" (Beta = 0.030; 95% CI: 0.010, 0.049; p = 0.003). Conclusion: The findings of our study revealed a suggestive causal relationship between hyperparathyroidism and blood cell count as well as biochemical markers. This presents a novel perspective for further investigating the etiology and pathological mechanisms underlying hyperparathyroidism.

Transcriptome-wide m6A methylation profiling of Wuhua yellow-feathered chicken ovary revealed regulatory pathways underlying sexual maturation and low egg-laying performance.

RNA N6-melthyladenosine (m6A) can play an important role in regulation of various biological processes. Chicken ovary development is closely related to egg laying performance, which is a process primarily controlled by complex gene regulations. In this study, transcriptome-wide m6A methylation of the Wuhua yellow-feathered chicken ovaries before and after sexual maturation was profiled to identify the potential molecular mechanisms underlying chicken ovary development. The results indicated that m6A levels of mRNAs were altered dramatically during sexual maturity. A total of 1,476 differential m6A peaks were found between these two stages with 662 significantly upregulated methylation peaks and 814 downregulated methylation peaks after sexual maturation. A positive correlation was observed between the m6A peaks and gene expression levels, indicating that m6A may play an important role in regulation of chicken ovary development. Functional enrichment analysis indicated that apoptosis related pathways could be the key molecular regulatory pathway underlying the poor reproductive performance of Wuhua yellow-feathered chicken. Overall, the various pathways and corresponding candidate genes identified here could be useful to facilitate molecular design breeding for improving egg production performance in Chinese local chicken breed, and it might also contribute to the genetic resource protection of valuable avian species.

Optimization of the Extraction Strategy for Polyphenols from Pieris Japonica and Evaluation of Its Antioxidant Activity.

Pieris Japonica, belonging to the Rhododendron family, is known for its anti-insect and analgesic properties. Despite previous research, the components and antioxidant activity of Pieris Japonica extract remain unclear. This study aims to identify the optimal extraction process for Pieris Japonica, determine its components, and evaluate its antioxidant capacity. An L9 (34) orthogonal method was employed to optimize the Pieris Japonica extraction process, with the polyphenol content serving as the extraction efficiency index. The extracted components were identified by high-performance liquid chromatography-mass spectrometry (HPLC/MS-MS). Antioxidant activity was assessed via the DPPH test, ABTS radical scavenging test, and FRAP reduction ability test. The optimal extraction process involved soaking Pieris Japonica powder in 60% ethanol with a weight-to-volume ratio of 1:20 (g/mL), followed by eight hours of reflux at 50°C. Under these conditions, the total polyphenol content was 11.2 ± 0.6 mg/g. HPLC/MS-MS revealed that flavonoids were the primary components in the Pieris Japonica extract. The FRAP method determined the total antioxidant capacity to be 1.00 ± 0.05 µmol/mL, while the DPPH method showed a radical scavenging rate of 42.21 ± 4.02%, and the ABTS method yielded a 85.74% scavenging rate, indicating a strong antioxidant activity. The primary components of Pieris Japonica extract were flavonoids, and the extracted plant material exhibited potent antioxidant activity.

C3N nanodots inhibits Aß peptides aggregation pathogenic path in Alzheimer's disease.

Despite the accumulating evidence linking the development of Alzheimer's disease (AD) to the aggregation of Aß peptides and the emergence of Aß oligomers, the FDA has approved very few anti-aggregation-based therapies over the past several decades. Here, we report the discovery of an Aß peptide aggregation inhibitor: an ultra-small nanodot called C3N. C3N nanodots alleviate aggregation-induced neuron cytotoxicity, rescue neuronal death, and prevent neurite damage in vitro. Importantly, they reduce the global cerebral Aß peptides levels, particularly in fibrillar amyloid plaques, and restore synaptic loss in AD mice. Consequently, these C3N nanodots significantly ameliorate behavioral deficits of APP/PS1 double transgenic male AD mice. Moreover, analysis of critical tissues (e.g., heart, liver, spleen, lung, and kidney) display no obvious pathological damage, suggesting C3N nanodots are biologically safe. Finally, molecular dynamics simulations also reveal the inhibitory mechanisms of C3N nanodots in Aß peptides aggregation and its potential application against AD.

Green carbon dots derived from Atractylodes macrocephala: A potential nanodrug for treating alcoholic gastric ulcer.

Alcoholic gastric ulcer is a common acute gastric injury disease. The drugs currently used in clinical practice not only cannot fundamentally treat gastric injury, but also have serious side effects. There is an urgent demand for the discovery of a mild drug to treat alcoholic gastric ulcers. Herein, the green carbon dots derived from charred Atractylodes macrocephala (CAM-CDs) were acquired and have been proven to be safe and effective in alleviating alcoholic gastric ulcers at an inhibition rate up to 60%. CAM-CDs can markedly attenuate the gastric mucosa damage such as mucosal defect, bleeding and inflammatory cell infiltration by histopathological examination. Serum and tissue inflammatory cytokine measurements, as well as immunohistochemistry results, indicate that its mechanism of gastric mucosal protection may involve the reduction of IL-1ß and TNF-α by regulating inflammatory signaling pathway of the NF-κB/NLRP3 axis, as well as elevation of IL-10 levels. CAM-CDs also can reduce oxidative stress markers (MDA), increase PGE2 and mucin secretion (MUC5AC), and it simultaneously exerts slight inhibition of hydrogen potassium ATPase and pepsin activity to protect gastric mucosa, as well as increases the microbial diversity and regulates species composition of gut microbiota in rats with gastric ulcer. Our work provides a new perspective on utilizing carbon-based nanomaterials in the development of new mild drugs.

Effect of Chromium Carbide Addition on the Microstructures and Properties in Dual Carbide Phases Reinforced Ni-Based Composite Coatings by Plasma Cladding.

Cr3C2-modified NiCr-TiC composite coatings were prepared using the plasma spraying technique for different Cr3C2 contents on the microstructure and the properties of the Ni-based TiC cladding layer were investigated. The microstructures of the coatings were characterized using scanning electron microscopy, and the friction and wear performance of the coating was evaluated by the wear tests. The results revealed that the surfaces of the Cr3C2-modified NiCr-TiC composite coatings with varying Cr3C2 contents were dense and smooth. TiC was uniformly distributed throughout the entire coating, forming a gradient interface between the binder phase of the Ni-based alloy and the hard phase of TiC. At high temperatures, Cr3C2 decomposes, with some chromium diffusing and forming complex carbides around TiC, some chromium solubilizes with Fe, Ni, and other elements. An increase in chromium carbide content leads to an upward trend in hardness. The measured hardness of the coatings ranged from 600 to 850 HV3 and tended to increase with increasing Cr3C2 content. When the mass fraction of Cr3C2 reached 30%, the hardness increased to 850 HV3, and the cracks and defects were observed in the coating, resulting in a wear resistance decline.