Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 1.179
Filter
1.
Rev Sci Instrum ; 95(6)2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38829216

ABSTRACT

Non-destructive measurements of low-intensity charged particle beams are particularly challenging for beam diagnostics. At the Heavy Ion Accelerator Facility in Lanzhou (HIRFL), beams with weak currents below 1 µA are often provided for experiments. The detection of such low beam current is below the threshold of typical standard beam current transformers. Therefore, a low-intensity monitoring system is developed by using a sensitive capacitive pick-up (PU) and low-noise electronics. This device measures beam currents by digitally analyzing the amplitude of the PU signals using a homodyne detection scheme. During lab tests, the amplitude nonlinearity is <0.5% in the operational range of 1 nA-45 µA and the amplitude resolution is 0.94 nA. At present, four measurement systems for low beam currents are installed at HIRFL for the monitoring of standard operating conditions with low beam currents below 1 µA. After an absolute calibration with a Faraday cup, it can be used for accurate beam intensity measurement with a current resolution of about 1 nA.

2.
J Med Virol ; 96(5): e29664, 2024 May.
Article in English | MEDLINE | ID: mdl-38727137

ABSTRACT

The causative agent of coronavirus disease 2019 (COVID-19), known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread accumulatively to 240 countries and continues to evolve. To gain a comprehensive understanding of the epidemiological characteristics of imported variants in China and their correlation with global circulating variants, genomic surveillance data from 11 139 imported COVID-19 cases submitted by Chinese provincial CDC laboratories between 2021 and 2022 were analyzed. Consensus sequences underwent rigorous quality checks, followed by amino acid mutations analysis using Nextclade. Sequences with satisfactory quality control status were classified according to the Pango nomenclature. The results showed that the dominant variants in imported cases reflected the global epidemic trend. An increase in the number of imported SARS-CoV-2 lineages monitored in China in the second half of 2022, and the circulating Omicron subvariants changed from the ancestral lineages of BA.5 and BA.2 into the lineages containing key amino acid mutations of spike protein. There was significant variation in the detection of Omicron subvariants among continents (χ2 = 321.968, p < 0.001) in the second half of 2022, with four lineages (BA.2.3.7, BA.2.2, BA.5.2.7, and XBB.1.2) identified through imported surveillance mainly prevalent respectively in Taiwan, China, Hong Kong SAR, China, Russian Federation, and Singapore. These findings revealed the alterations in circulating imported variants from 2021 to 2022 in China, reflecting the higher diversity of lineages in the second half of 2022, and revealed the predominant lineages of countries or regions that are in close contacts to China, providing new insights into the global prevalence of SARS-CoV-2.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , China/epidemiology , COVID-19/epidemiology , COVID-19/virology , SARS-CoV-2/genetics , SARS-CoV-2/classification , Prevalence , Spike Glycoprotein, Coronavirus/genetics , Phylogeny , Mutation , Genome, Viral/genetics , Genetic Variation
3.
Pediatr Surg Int ; 40(1): 115, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38696138

ABSTRACT

OBJECTIVE: This study aimed to evaluate the role of receptor-interacting protein kinase-3 (RIPK3) in the diagnosis, estimation of disease severity, and prognosis of premature infants with necrotising enterocolitis (NEC). METHODS: RIPK3, lactic acid (LA), and C-reactive protein (CRP) levels were measured in the peripheral blood of 108 premature infants between 2019 and 2023, including 24 with stage II NEC, 18 with stage III NEC and 66 controls. Diagnostic values of the indicators for NEC were evaluated via receiver operating characteristic (ROC) curve analysis. RESULTS: Plasma RIPK3 and LA levels upon NEC suspicion in neonates with stage III NEC were 32.37 ± 16.20 ng/mL. The ROC curve for the combination of RIPK3, LA, CRP for NEC diagnosis were 0.925. The time to full enteral feeding (FEFt) after recovery from NEC was different between two expression groups of plasma RIPK3 (RIPK3 < 20.06 ng/mL and RIPK3 ≥ 20.06 ng/mL). CONCLUSION: Plasma RIPK3 can be used as a promising marker for the diagnosis and estimation of disease severity of premature infants with NEC and for the guidance on proper feeding strategies after recovery from NEC.


Subject(s)
Biomarkers , Enterocolitis, Necrotizing , Infant, Premature , Receptor-Interacting Protein Serine-Threonine Kinases , Humans , Enterocolitis, Necrotizing/blood , Enterocolitis, Necrotizing/diagnosis , Infant, Newborn , Receptor-Interacting Protein Serine-Threonine Kinases/blood , Biomarkers/blood , Male , Female , C-Reactive Protein/metabolism , C-Reactive Protein/analysis , Prognosis , ROC Curve , Severity of Illness Index , Infant, Premature, Diseases/blood , Infant, Premature, Diseases/diagnosis , Case-Control Studies , Lactic Acid/blood
4.
Front Neurol ; 15: 1360434, 2024.
Article in English | MEDLINE | ID: mdl-38784898

ABSTRACT

Objective: To compare the effects of various sports exercise programs on the core symptoms of patients with autism spectrum disorder (ASD). Methods: We searched the China National Knowledge Infrastructure, VIP databases, Wanfang databases, Cochrane Library, PubMed, EMBASE, and Web of Science databases from their inception to February 2023 for randomized controlled trial that investigated the effect of sports exercise on the core symptoms of ASD. The overall risk of bias in the included literature was summarized using the revised Cochrane Randomized Trial Risk of Bias Tool (ROB2), and network meta-analysis was used to compare the intervention effects. Results: A total of 30 studies involving 1,375 participants were included. The results showed that sports exercise programs, including 8-12 weeks of ball sports (SMD = -5.35, 95%CI: -7.57, -3.23), horse riding (SMD = -3.71, 95%CI: -6.18, -1.13), 8-12 weeks of comprehensive sports exercise (SMD = -2.17, 95%CI: -3.99, -0.44), and more than 12 weeks of comprehensive sports exercise (SMD = -3.75, 95%CI: -6.33, -1.24), significantly improved social interaction disorders. Furthermore, 8-12 weeks of ball sports (SMD = -4.36, 95%CI: 2.04, 6.73) and more than 12 weeks of comprehensive sports exercise (SMD = 3.65, 95%CI: 1.40, 6.08) significantly improved repetitive behaviors and restricted interests. Conclusion: Sports exercise can improve the core symptoms of ASD patients, and different symptoms show a selective response to different exercise elements. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023455806.

5.
Polymers (Basel) ; 16(9)2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38732668

ABSTRACT

Thermal-mechanical coupling during the molding process can cause compressive yield in the polymer foam core and then affect the molding quality of the sandwich structure. This work investigates the compressive mechanical properties and failure mechanism of polymethacrylimide (PMI) foam in the molding temperature range of 20-120 °C. First, the DMA result indicates that PMI foam has minimal mechanical loss in the 20~120 °C range and can be regarded as an elastoplastic material, and the TGA curve further proves that the PMI foam is thermally stable within 120 °C. Then, the compression results show that compared with 20 °C, the yield stress and elastic modulus of PMI foam decrease by 22.0% and 17.5% at 80 °C and 35.2% and 31.4% at 120 °C, respectively. Meanwhile, the failure mode changes from brittle fracture to plastic yield at about 80 °C. Moreover, a real representative volume element (rRVE) of PMI foam is established by using Micro-CT and Avizo 3D reconstruction methods, and the simulation results indicate that PMI foam mainly shows brittle fractures at 20 °C, while both brittle fractures and plastic yield occur at 80 °C, and most foam cells undergo plastic yield at 120 °C. Finally, the simulation based on a single-cell RVE reveals that the air pressure inside the foam has an obvious influence of about 6.7% on the yield stress of PMI foam at 80 °C (brittle-plastic transition zone).

6.
China CDC Wkly ; 6(15): 324-331, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38736991

ABSTRACT

Introduction: In the first half of 2023, a global shift was observed towards the predominance of XBB variants. China faced a significant epidemic between late 2022 and early 2023 due to Omicron subvariants BA.5.2 and BF.7. This study aims to depict the evolving variant distribution among provincial-level administrative divisions (PLADs) in China and explore the factors driving the predominance of XBB replacement. Methods: Sequences from local and imported coronavirus disease 2019 (COVID-19) cases recorded between January 1 and June 30, 2023, were included. The study analyzed the changing distribution of viral variants and assessed how the prior dominance of specific variants, XBB subvariants, and imported cases influenced the prevalence of the XBB replacement variant. Results: A total of 56,486 sequences were obtained from local cases, and 8,669 sequences were from imported cases. Starting in April, there was a shift in the prevalence of XBB from imported to local cases, with varying dominance among PLADs. In PLADs previously high in BF.7, the rise of XBB was delayed. A positive correlation was found between XBB proportions in imported cases from January to March and local cases in April. The distribution pattern of XBB subvariants differed between local and imported cases within the same PLAD. No significant differences were noted in the replacement rates of XBB subvariants. Conclusions: The timing of XBB dominance differed among various PLADs in China in the first half of 2023, correlating closely with the prevalence of XBB variants among imported cases.

7.
PeerJ ; 12: e17370, 2024.
Article in English | MEDLINE | ID: mdl-38737737

ABSTRACT

Cysteine-rich receptor-like kinases (CRKs) play many important roles during plant development, including defense responses under both biotic and abiotic stress, reactive oxygen species (ROS) homeostasis, callose deposition and programmed cell death (PCD). However, there are few studies on the involvement of the CRK family in male sterility due to heat stress in wheat (Triticum aestivum L.). In this study, a genome-wide characterization of the CRK family was performed to investigate the structural and functional attributes of the wheat CRKs in anther sterility caused by heat stress. A total of 95 CRK genes were unevenly distributed on 18 chromosomes, with the most genes distributed on chromosome 2B. Paralogous homologous genes with Ka/Ks ratios less than 1 may have undergone strong purifying selection during evolution and are more functionally conserved. The collinearity analysis results of CRK genes showed that wheat and Arabidopsis (A. thaliana), foxtail millet, Brachypodium distachyon (B. distachyon), and rice have three, 12, 15, and 11 pairs of orthologous genes, respectively. In addition, the results of the network interactions of genes and miRNAs showed that five miRNAs were in the hub of the interactions map, namely tae-miR9657b-5p, tae-miR9780, tae-miR9676-5p, tae-miR164, and tae-miR531. Furthermore, qRT-PCR validation of the six TaCRK genes showed that they play key roles in the development of the mononuclear stage anthers, as all six genes were expressed at highly significant levels in heat-stressed male sterile mononuclear stage anthers compared to normal anthers. We hypothesized that the TaCRK gene is significant in the process of high-temperature-induced sterility in wheat based on the combination of anther phenotypes, paraffin sections, and qRT-PCR data. These results improve our understanding of their relationship.


Subject(s)
Gene Expression Regulation, Plant , Plant Infertility , Triticum , Triticum/genetics , Plant Infertility/genetics , Plant Proteins/genetics , Plant Proteins/metabolism , Genome, Plant/genetics , Hot Temperature/adverse effects , Multigene Family , Chromosomes, Plant/genetics , Heat-Shock Response/genetics , Gene Expression Profiling
8.
Plant Physiol Biochem ; 211: 108665, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38735155

ABSTRACT

Budding mutations are known to cause metabolic changes in new jujube varieties; however, the mechanisms underlying these changes are still unclear. Here, we performed muti-omics analysis to decipher the detailed metabolic landscape of "Saimisu 1" (S1) and its budding mutation line "Saimisu 2" (S2) at all fruit stages. We found that the genes involved in the biosyntheses of flavonoids, phenylpropanoids, and amino acids were upregulated in S2 fruits at all stages, especially PAL and DFR, resulting in increased accumulation of related compounds in S2 mature fruits. Further co-expression regulatory network analysis showed that the transcription factors MYB41 and bHLH93 potentially regulated the expression of PAL and DFR, respectively, by directly binding to their promoters. Moreover, the overexpression of MYB41 or bHLH93 induced their expression levels to redirect the flux of the flavonoid biosynthetic pathway, eventually leading to high levels of related compounds in S2 fruits. Overall, this study revealed the metabolic variations between S1 and S2 and contributed to the understanding of the mechanisms underlying budding mutation-mediated metabolic variations in plants, eventually providing the basis for breeding excellent jujube varieties using budding mutation lines.


Subject(s)
Basic Helix-Loop-Helix Transcription Factors , Flavonoids , Gene Expression Regulation, Plant , Mutation , Plant Proteins , Ziziphus , Flavonoids/metabolism , Flavonoids/biosynthesis , Flavonoids/genetics , Ziziphus/genetics , Ziziphus/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Basic Helix-Loop-Helix Transcription Factors/genetics , Basic Helix-Loop-Helix Transcription Factors/metabolism , Transcription Factors/metabolism , Transcription Factors/genetics , Fruit/genetics , Fruit/metabolism
9.
Ann Rheum Dis ; 2024 May 30.
Article in English | MEDLINE | ID: mdl-38816066

ABSTRACT

OBJECTIVES: Arterial wall inflammation and remodelling are the characteristic features of Takayasu's arteritis (TAK). It has been proposed that vascular smooth muscle cells (VSMCs) are the main targeted cells of inflammatory damage and participate in arterial remodelling in TAK. Whether VSMCs are actively involved in arterial wall inflammation has not been elucidated. Studies have shown that cellular senescence in tissue is closely related to local inflammation persistence. We aimed to investigate whether VSMCs senescence contributes to vascular inflammation and the prosenescent factors in TAK. METHODS: VSMCs senescence and senescence-associated secretory phenotype were detected by histological examination, bulk RNA-Seq and single-cell RNA-seq conducted on vascular surgery samples of TAK patients. The key prosenescent factors and the downstream signalling pathway were investigated in a series of in vitro and ex vivo experiments. RESULTS: Histological findings, primary cell culture and transcriptomic analyses demonstrated that VSMCs of TAK patients had the features of premature senescence and contributed substantially to vascular inflammation by upregulating the expression of senescence-associated inflammatory cytokines. IL-6 was found to be the critical cytokine that drove VSMCs senescence and senescence-associated mitochondrial dysfunction in TAK. Mechanistically, IL-6-induced non-canonical mitochondrial localisation of phosphorylated STAT3 (Tyr705) prevented mitofusin 2 (MFN2) from proteasomal degradation, and subsequently promoted senescence-associated mitochondrial dysfunction and VSMCs senescence. Mitochondrial STAT3 or MFN2 inhibition ameliorated VSMCs senescence in ex vivo cultured arteries of TAK patients. CONCLUSIONS: VSMCs present features of cellular senescence and are actively involved in vascular inflammation in TAK. Vascular IL-6-mitochondrial STAT3-MFN2 signalling is an important driver of VSMCs senescence.

10.
Plant Signal Behav ; 19(1): 2357367, 2024 Dec 31.
Article in English | MEDLINE | ID: mdl-38775124

ABSTRACT

Elevated temperatures critically impact crop growth, development, and yield, with photosynthesis being the most temperature-sensitive physiological process in plants. This study focused on assessing the photosynthetic response and genetic adaptation of two different heat-resistant jujube varieties 'Junzao' (J) and 'Fucuimi' (F), to high-temperature stress (42°C Day/30°C Night). Comparative analyses of leaf photosynthetic indices, microstructural changes, and transcriptome sequencing were conducted. Results indicated superior high-temperature adaptability in F, evidenced by alterations in leaf stomatal behavior - particularly in J, where defense cells exhibited significant water loss, shrinkage, and reduced stomatal opening, alongside a marked increase in stomatal density. Through transcriptome sequencing 13,884 differentially expressed genes (DEGs) were identified, significantly enriched in pathways related to plant-pathogen interactions, amino acid biosynthesis, starch and sucrose metabolism, and carbohydrate metabolism. Key findings include the identification of photosynthetic pathway related DEGs and HSFA1s as central regulators of thermal morphogenesis and heat stress response. Revealing their upregulation in F and downregulation in J. The results indicate that these genes play a crucial role in improving heat tolerance in F. This study unveils critical photosynthetic genes involved in heat stress, providing a theoretical foundation for comprehending the molecular mechanisms underlying jujube heat tolerance.


Subject(s)
Gene Expression Regulation, Plant , Photosynthesis , Ziziphus , Ziziphus/genetics , Ziziphus/physiology , Photosynthesis/genetics , Heat-Shock Response/genetics , Hot Temperature , Plant Leaves/genetics , Plant Leaves/metabolism , Transcriptome/genetics , Plant Proteins/genetics , Plant Proteins/metabolism , Plant Stomata/physiology , Plant Stomata/genetics
11.
Genes (Basel) ; 15(5)2024 May 08.
Article in English | MEDLINE | ID: mdl-38790228

ABSTRACT

Alginate is derived from brown algae, which can be cultivated in large quantities. It can be broken down by alginate lyase into alginate oligosaccharides (AOSs), which exhibit a higher added value and better bioactivity than alginate. In this study, metagenomic technology was used to screen for genes that code for high-efficiency alginate lyases. The candidate alginate lyase gene alg169 was detected from Psychromonas sp. SP041, the most abundant species among alginate lyase bacteria on selected rotten kelps. The alginate lyase Alg169 was heterologously expressed in Escherichia coli BL21 (DE3), Ni-IDA-purified, and characterized. The optimum temperature and pH of Alg169 were 25 °C and 7.0, respectively. Metal ions including Mn2+, Co2+, Ca2+, Mg2+, Ni2+, and Ba2+ led to significantly increased enzyme activity. Alg169 exhibited a pronounced dependence on Na+, and upon treatment with Mn2+, its activity surged by 687.57%, resulting in the highest observed enzyme activity of 117,081 U/mg. Bioinformatic analysis predicted that Alg169 would be a double-domain lyase with a molecular weight of 65.58 kDa. It is a bifunctional enzyme with substrate specificity to polyguluronic acid (polyG) and polymannuronic acid (polyM). These results suggest that Alg169 is a promising candidate for the efficient manufacturing of AOSs from brown seaweed.


Subject(s)
Alginates , Kelp , Metagenomics , Polysaccharide-Lyases , Polysaccharide-Lyases/genetics , Polysaccharide-Lyases/metabolism , Polysaccharide-Lyases/chemistry , Metagenomics/methods , Kelp/genetics , Alginates/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Escherichia coli/genetics , Substrate Specificity , Chloroflexi/genetics , Chloroflexi/enzymology
12.
BMC Ecol Evol ; 24(1): 62, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38735962

ABSTRACT

The epiphytic and endophytic bacteria play an important role in the healthy growth of plants. Both plant species and growth environmental influence the bacterial population diversity, yet it is inconclusive whether it is the former or the latter that has a greater impact. To explore the communities of the epiphytic and endophytic microbes in Camellia oleifera, this study assessed three representative C. oleifera cultivars from three areas in Hunan, China by Illumina high-throughput sequencing. The results showed that the diversity and species richness of endophytic microbial community in leaves were significantly higher than those of microbial community in the epiphytic. The diversity and species richness of epiphytic and endophytic microbes are complex when the same cultivar was grown in different areas. The C. oleifera cultivars grown in Youxian had the highest diversity of epiphytic microbial community, but the lowest abundance, while the cultivars grown in Changsha had the highest diversity and species richness of endophytic microbes in leaves. It was concluded that the dominant phylum mainly included Proteobacteria, Actinobacteriota and Firmicutes through the analysis of the epiphytic and endophytic microbial communities of C. oleifera. The species and relative abundances of epiphytic and endophytic microbial community were extremely different at the genus level. The analysis of NMDS map and PERMANOVA shows that the species richness and diversity of microbial communities in epiphytes are greatly influenced by region. However, the community structure of endophytic microorganisms in leaves is influenced by region and cultivated varieties, but the influence of cultivars is more significant. Molecular ecological network analysis showed that the symbiotic interaction of epiphytic microbial community was more complex.


Subject(s)
Bacteria , Camellia , Endophytes , Microbiota , Plant Leaves , Camellia/microbiology , Endophytes/physiology , Endophytes/genetics , Endophytes/isolation & purification , Bacteria/classification , Bacteria/isolation & purification , Bacteria/genetics , China , Plant Leaves/microbiology , Biodiversity
13.
Redox Biol ; 73: 103175, 2024 May 05.
Article in English | MEDLINE | ID: mdl-38795544

ABSTRACT

Exploring and discovering novel circRNAs is one of the ways to develop innovative drugs for the diagnosis and treatment of myocardial ischemia-reperfusion injury (MI/RI). In the work, some dysregulated circRNAs were found by microarray screening analysis in AC16 cells, and hsa_circRNA_104852 named circMIRIAF was screened, which was up-regulated in AC16 cells damaged by hypoxia-reoxygenation injury (H/RI). The comprehensive analysis of ceRNA network revealed the potential relationship of circMIRIAF/miR-544/WDR12. Then, the results of interaction research confirmed that circMIRIAF acted as sponge of miR-544 to positively regulate WDR12 protein expression. Further, the validation results indicate that miR-544 silencing increased the expression of WDR12, and WDR12 activated Notch1 signal to aggravate H/RI of AC16 cells and MI/RI of mice via regulating oxidative stress and inflammation. Furthermore, silencing circMIRIAF caused the decreased circMIRIAF levels and the increased miR-544 levels in cardiomyocytes, while excessive miR-544 inhibited WDR12 expression to alleviate the disorder. On the contrary, excessive circMIRIAF increased WDR12 expression by adsorbing miR-544 to exacerbate H/RI in AC16 cells. In addition, circMIRIAF siRNA reversed the aggravation of H/RI in cells caused by WDR12 overexpression. Overall, circMIRIAF can serve as a drug target or treating MI/RI, and circMIRIAF could sponge miR-544 and enhance WDR12 expression to aggravate MI/RI, which may provide a novel therapeutic strategy for MI/RI treatment.

14.
Food Funct ; 2024 May 28.
Article in English | MEDLINE | ID: mdl-38804210

ABSTRACT

Acrylamide (AA) is a toxic food contaminant that has been reported to cause glucose metabolism disorders (GMD) at high doses. However, it is unclear whether chronic low-dose AA can induce GMD and whether probiotics can alleviate AA-induced GMD. Here, C57BL/6N mice were orally administered with 5 mg per kg bw AA for 10 weeks, followed by another 3 weeks of glucagon-like peptide-1 (GLP-1) analogue (dulaglutide) treatment. Chronic low-dose AA exposure increased the blood glucose level and decreased serum insulin and GLP-1 levels, whereas dulaglutide treatment decreased the blood glucose level and increased the serum insulin level in AA-exposed mice. Then, mice were administered with AA or AA + INT-777 (Takeda G-protein-coupled receptor 5 (TGR5) agonist) for 10 weeks. INT-777 treatment reversed AA-induced downregulation of ileal TGR5 and proglucagon (PG) gene expression and decreased the serum GLP-1 level. These findings indicated that chronic low-dose AA induced GMD via inhibiting the TGR5-GLP-1 axis. Finally, mice were administered with AA for 10 weeks, followed by another 3 weeks of Lactobacillus reuteri JCM 1112 supplementation. L. reuteri supplementation significantly increased serum glucose, insulin and GLP-1 levels, upregulated ileal TGR5 and PG gene expression, and effectively restored the imbalance of bile acid (BA) metabolism in AA-exposed mice, demonstrating that L. reuteri ameliorates chronic AA-induced GMD via the BA-TGR5-GLP-1 axis. In addition, L. reuteri significantly enhanced ileal superoxide dismutase and catalase activities and total antioxidant capacity, thereby preventing chronic AA-induced oxidative stress. Our research provides new insights into the GMD toxicity of chronic low-dose AA and confirms the role of probiotics in alleviating AA-induced GMD.

15.
ACS Nano ; 18(22): 14496-14506, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38771969

ABSTRACT

Hydrogen obtained from electrochemical water splitting is the most promising clean energy carrier, which is hindered by the sluggish kinetics of the oxygen evolution reaction (OER). Thus, the development of an efficient OER electrocatalyst using nonprecious 3d transition elements is desirable. Multielement synergistic effect and lattice oxygen oxidation are two well-known mechanisms to enhance the OER activity of catalysts. The latter is generally related to the high valence state of 3d transition elements leading to structural destabilization under the OER condition. We have found that Al doping in nanosheet Ni-Fe hydroxide exhibits 2-fold advantage: (1) a strong enhanced OER activity from 277 mV to 238 mV at 10 mA cm-2 as the Ni valence state increases from Ni3.58+ to Ni3.79+ observed from in situ X-ray absorption spectra. (2) Operational stability is strengthened, while weakness is expected since the increased NiIV content with 3d8L2 (L denotes O 2p hole) would lead to structural instability. This contradiction is attributed to a reduced lattice oxygen contribution to the OER upon Al doping, as verified through in situ Raman spectroscopy, while the enhanced OER activity is interpreted as an enormous gain in exchange energy of FeIV-NiIV, facilitated by their intersite hopping. This study reveals a mechanism of Fe-Ni synergy effect to enhance OER activity and simultaneously to strengthen operational stability by suppressing the contribution of lattice oxygen.

16.
Org Lett ; 26(22): 4711-4715, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38809207

ABSTRACT

The Catellani reaction offers an opportunity to address multiple chemical bonds in a single pot. However, it is still quite a challenge to construct fully substituted olefins via this strategy, especially in electron-rich, unstable, and highly functionalized glycals. Herein we report the first palladium-catalyzed Catellani reaction for the direct preparation of 1,2-disubstituted C-aryl glycosides from easily available 2-iodoglycals, bromoaryl, and alkene/alkyne substrates. This transformation exhibits a wide substrate scope, accommodating diverse functional groups and intricate molecular frameworks. This innovative reactivity offers an efficient pathway to valuable 1,2-disubstituted carbohydrate analogues and molecular building blocks, facilitating novel strategic bond disconnections and broadening the reactivity landscape of palladium catalysis.

17.
Acupunct Med ; 42(3): 123-132, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38813841

ABSTRACT

BACKGROUND: Electroacupuncture (EA) has been reported to improve intestinal motility in mice with postoperative ileus (POI). Previous studies, however, have yielded heterogeneous results regarding the effect of EA on POI. METHODS: Herein, a POI mouse model was constructed by intestinal manipulation. To evaluate the effect of EA treatment on colonic transit, the levels of inflammatory markers (macrophage inflammatory protein (MIP)-1α, interleukin (IL)-1ß, IL-6, monocyte chemotactic protein (MCP)-1 and intercellular adhesion molecule (ICAM)-1) were detected by enzyme-linked immunosorbent assay (ELISA); immune cell infiltration was detected by immunohistochemical staining of myeloperoxidase (MPO), ectodysplasin (ED)-1 and ED-2, and the percentage of CD4+ interferon (IFN)-γ+ Th1 cells and IFN-γ secretion levels were determined. Activated Th1 cells and pentoxifylline, a cell differentiation inhibitor, were used to assess the role of Th1 cells in EA treatment of POI. Neostigmine administration and unilateral vagotomy were performed to confirm whether the effects of EA treatment on Th1 cells were mediated by the vagus nerve (VN). RESULTS: The results revealed that EA treatment at ST36 improved POI, as indicated by a decreased level of inflammatory-related markers and immune cell infiltration and shortened colonic transit time. The activated Th1 cells abolished the effects of EA treatment on POI. The effects of EA treatment on POI were enhanced by stimulation of the VN along with a decreased level of Th1 cells, but these effects were abolished by vagotomy along with an increased percentage of Th1 cells; this result indicates that the VN mediates the role of Th1 cells in the effects of EA treatment of POI. CONCLUSION: Our findings showed that the effects of EA treatment of POI were mainly mediated by Th1 cells through the stimulation of the VN and inhibition of the inflammatory response.


Subject(s)
Electroacupuncture , Ileus , Postoperative Complications , Th1 Cells , Vagus Nerve , Animals , Th1 Cells/immunology , Mice , Ileus/therapy , Ileus/immunology , Vagus Nerve/immunology , Male , Humans , Postoperative Complications/therapy , Postoperative Complications/immunology , Mice, Inbred C57BL , Disease Models, Animal , Interferon-gamma/metabolism , Interferon-gamma/immunology , Interleukin-6/metabolism , Interleukin-6/immunology , Intercellular Adhesion Molecule-1/metabolism , Intercellular Adhesion Molecule-1/genetics , Interleukin-1beta/metabolism , Inflammation/therapy
18.
Small ; : e2400042, 2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38600889

ABSTRACT

Modulating the coordination environment of the metal active center is an effective method to boost the catalytic performances of metal-organic frameworks (MOFs) for oxygen evolution reaction (OER). However, little attention has been paid to the halogen effects on the ligands engineering. Herein, a series of MOFs X─FeNi-MOFs (X = Br, Cl, and F) is constructed with different coordination microenvironments to optimize OER activity. Theoretical calculations reveal that with the increase in electronegativity of halogen ions in terephthalic acid molecular (TPA), the Bader charge of Ni atoms gets larger and the Ni-3d band center and O-2p bands move closer to the Fermi level. This indicates that an increase in ligand negativity of halogen ions in TPA can promote the adsorption ability of catalytic sites to oxygen-containing intermediates and reduce the activation barrier for OER. Experimental also demonstrates that F─FeNi-MOFs exhibit the highest catalytic activity with an ultralow overpotential of 218 mV at 10 mA cm-2, outperforming most otate-of-the-art Fe/Co/Ni-based MOFs catalysts, and the enhanced mass activity by seven times compared with that for the sample before ligands engineering. This work opens a new avenue for the realization of the modulation of NiFe─O bonding by halogen ion in TPA and improves the OER performance of MOFs.

19.
J Clin Ultrasound ; 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38561934

ABSTRACT

OBJECTIVE: To analyze the value of prenatal ultrasound and molecular testing in diagnosing fetal skeletal dysplasia (SD). METHODS: Clinical data, prenatal ultrasound data, and molecular results of pregnant women with fetal SD were collected in the ultrasound department of our clinic from May 2019 to December 2021. RESULTS: A total of 40 pregnant women with fetal SD were included, with 82.5% exhibiting short limb deformity, followed by 25.0% with central nervous system malformations, 17.50% with facial malformations, 15% with cardiac malformations, and 12.5% with urinary system malformations. The genetic testing positive rate was 70.0% (28/40), with 92.8% (26/28) being single-gene disorders due to mutations in FGFR3, COL1A1, COL1A2, EVC2, FLNB, LBR, and TRPV4 genes. The most common SD subtypes were osteogenesis imperfecta (OI), thanatophoric dysplasia (TD), and achondroplasia (ACH). The gestational age (GA) at initial diagnosis for TD, OI, and ACH was 16.6, 20.9, and 28.3 weeks, respectively (p < 0.05), with no significant difference in femoral shortening between the three groups (p > 0.05). Of the OI cases, 5 out of 12 had a family history. CONCLUSION: Short limb deformity is the most prevalent phenotype of SD. When fetal SD is suspected, detailed ultrasound screening should be conducted, combined with GA at initial diagnosis, family history, and molecular evidence, to facilitate more accurate diagnosis and enhance prenatal counseling and perinatal management.

20.
Medicine (Baltimore) ; 103(16): e37792, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38640281

ABSTRACT

Currently, few studies have demonstrated the relationship between total serum IgE (T-IgE) and acute exacerbation chronic obstructive pulmonary disease (AECOPD). In this study, T-IgE in AECOPD patients were investigated and jointly analyzed with the clinical characteristics. AECOPD patients hospitalized from July 2018 to July 2019 were included in this study. In this patient cohort, clinical information was investigated. Routine blood tests, C-reactive protein and T-IgE levels of patients were determined along with blood gas analysis. The length of hospital stays, mechanical ventilation during hospitalization, ICU admission, glucocorticoid related clinical information were recorded. A total of 285 AECOPD patients were included in this study, which consisted of a high proportion of males. Of all patients, 49.82% patients exhibited higher T-IgE levels. Based on the reference T-IgE value 60 kU/L, patients were divided into high T-IgE group with T-IgE > 60 kU/L, and low T-IgE group with T-IgE ≤ 60 kU/L. There was no significant difference in the dosage of glucocorticoid between the two groups. Patients in the high T-IgE group had shorter hospital stays and lower probability of mechanical ventilation compared to the low T-IgE group. After adjustment for confounding factors, T-IgE was negatively correlated with the length of hospital stays. AECOPD patients with elevated T-IgE had shorter hospital stays and lower risks of mechanical ventilation and ICU admission. Our results showed that T-IgE might play an important role on evaluating the condition and guiding for treatment decisions in AECOPD patients.


Subject(s)
Glucocorticoids , Pulmonary Disease, Chronic Obstructive , Male , Humans , Retrospective Studies , Glucocorticoids/therapeutic use , Hospitalization , Pulmonary Disease, Chronic Obstructive/therapy , Immunoglobulin E , Disease Progression
SELECTION OF CITATIONS
SEARCH DETAIL
...