Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 424
Filter
Add more filters

Country/Region as subject
Publication year range
1.
Nature ; 622(7982): 292-300, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37704731

ABSTRACT

The past decades have witnessed the evolution of electronic and photonic integrated circuits, from application specific to programmable1,2. Although liquid-phase DNA circuitry holds the potential for massive parallelism in the encoding and execution of algorithms3,4, the development of general-purpose DNA integrated circuits (DICs) has yet to be explored. Here we demonstrate a DIC system by integration of multilayer DNA-based programmable gate arrays (DPGAs). We find that the use of generic single-stranded oligonucleotides as a uniform transmission signal can reliably integrate large-scale DICs with minimal leakage and high fidelity for general-purpose computing. Reconfiguration of a single DPGA with 24 addressable dual-rail gates can be programmed with wiring instructions to implement over 100 billion distinct circuits. Furthermore, to control the intrinsically random collision of molecules, we designed DNA origami registers to provide the directionality for asynchronous execution of cascaded DPGAs. We exemplify this by a quadratic equation-solving DIC assembled with three layers of cascade DPGAs comprising 30 logic gates with around 500 DNA strands. We further show that integration of a DPGA with an analog-to-digital converter can classify disease-related microRNAs. The ability to integrate large-scale DPGA networks without apparent signal attenuation marks a key step towards general-purpose DNA computing.


Subject(s)
Computers, Molecular , DNA , Algorithms , DNA/chemistry , Oligonucleotides/chemistry , MicroRNAs/classification , Disease/genetics
2.
Proc Natl Acad Sci U S A ; 121(11): e2312596121, 2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38437555

ABSTRACT

Self-assembled DNA crystals offer a precise chemical platform at the ångström-scale for DNA nanotechnology, holding enormous potential in material separation, catalysis, and DNA data storage. However, accurately controlling the crystallization kinetics of such DNA crystals remains challenging. Herein, we found that atomic-level 5-methylcytosine (5mC) modification can regulate the crystallization kinetics of DNA crystal by tuning the hybridization rates of DNA motifs. We discovered that by manipulating the axial and combination of 5mC modification on the sticky ends of DNA tensegrity triangle motifs, we can obtain a series of DNA crystals with controllable morphological features. Through DNA-PAINT and FRET-labeled DNA strand displacement experiments, we elucidate that atomic-level 5mC modification enhances the affinity constant of DNA hybridization at both the single-molecule and macroscopic scales. This enhancement can be harnessed for kinetic-driven control of the preferential growth direction of DNA crystals. The 5mC modification strategy can overcome the limitations of DNA sequence design imposed by limited nucleobase numbers in various DNA hybridization reactions. This strategy provides a new avenue for the manipulation of DNA crystal structure, valuable for the advancement of DNA and biomacromolecular crystallography.


Subject(s)
5-Methylcytosine , DNA , Crystallization , Catalysis , Crystallography
3.
Hum Genomics ; 18(1): 76, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38961447

ABSTRACT

BACKGROUND: Lipid-lowering drugs are widely used among the elderly, with some studies suggesting links to muscle-related symptoms. However, the causality remains uncertain. METHODS: Using the Mendelian randomization (MR) approach, we assessed the causal effects of genetically proxied reduced low-density lipoprotein cholesterol (LDL-C) through inhibitions of hydroxy-methyl-glutaryl-CoA reductase (HMGCR), proprotein convertase subtilisin/kexin type 9 (PCSK9), and Niemann-Pick C1-like 1 (NPC1L1) on sarcopenia-related traits, including low hand grip strength, appendicular lean mass, and usual walking pace. A meta-analysis was conducted to combine the causal estimates from different consortiums. RESULTS: Using LDL-C pooled data predominantly from UK Biobank, genetically proxied inhibition of HMGCR was associated with higher appendicular lean mass (beta = 0.087, P = 7.56 × 10- 5) and slower walking pace (OR = 0.918, P = 6.06 × 10- 9). In contrast, inhibition of PCSK9 may reduce appendicular lean mass (beta = -0.050, P = 1.40 × 10- 3), while inhibition of NPC1L1 showed no causal impact on sarcopenia-related traits. These results were validated using LDL-C data from Global Lipids Genetics Consortium, indicating that HMGCR inhibition may increase appendicular lean mass (beta = 0.066, P = 2.17 × 10- 3) and decelerate walking pace (OR = 0.932, P = 1.43 × 10- 6), whereas PCSK9 inhibition could decrease appendicular lean mass (beta = -0.048, P = 1.69 × 10- 6). Meta-analysis further supported the robustness of these causal associations. CONCLUSIONS: Genetically proxied HMGCR inhibition may increase muscle mass but compromise muscle function, PCSK9 inhibition could result in reduced muscle mass, while NPC1L1 inhibition is not associated with sarcopenia-related traits and this class of drugs may serve as viable alternatives to sarcopenia individuals or those at an elevated risk.


Subject(s)
Hydroxymethylglutaryl CoA Reductases , Mendelian Randomization Analysis , Proprotein Convertase 9 , Sarcopenia , Humans , Sarcopenia/genetics , Proprotein Convertase 9/genetics , Hydroxymethylglutaryl CoA Reductases/genetics , Cholesterol, LDL/blood , Cholesterol, LDL/genetics , Membrane Transport Proteins/genetics , Hypolipidemic Agents/therapeutic use , Hypolipidemic Agents/adverse effects , Membrane Proteins/genetics , Male , Female , Aged , Hand Strength
4.
J Nutr ; 154(2): 369-380, 2024 02.
Article in English | MEDLINE | ID: mdl-38122845

ABSTRACT

BACKGROUND: There is a U-shaped relationship between dietary selenium (Se) ingestion and optimal sperm quality. OBJECTIVES: This study aimed to investigate the optimal dietary dose and forms of Se for sperm quality of breeder roosters and the relevant mechanisms. METHODS: In experiment 1, 18-wk-old Jingbai laying breeder roosters were fed a Se-deficient base diet (BD, 0.06 mg Se/kg), or the BD + 0.1, 0.2, 0.3, 0.4, 0.5, or 1.0 mg Se/kg for 9 wk. In experiment 2, the roosters were fed the BD or the BD + sodium selenite (SeNa), seleno-yeast (SeY), or Se-nanoparticles (SeNPs) at 0.2 mg Se/kg for 9 wk. RESULTS: In experiment 1, added dietary 0.2 and 0.3 mg Se/kg led to higher sperm motility and lower sperm mortality than the other groups at weeks 5, 7, and/or 9. Furthermore, added dietary 0.2-0.4 mg Se/kg produced better testicular histology and/or lower testicular 8-hydroxy-deoxyguanosine than the other groups. Moreover, integrated testicular transcriptomic and cecal microbiomic analysis revealed that inflammation, cell proliferation, and apoptosis-related genes and bacteria were dysregulated by Se deficiency or excess. In experiment 2, compared with SeNa, SeNPs slightly increased sperm motility throughout the experiment, whereas SeNPs slightly reduced sperm mortality compared with SeY at week 9. Both SeY and SeNPs decreased malondialdehyde in the serum than those of SeNa, and SeNPs led to higher glutathione peroxidase (GPX) and thioredoxin reductase activities and GPX1 and B-cell lymphoma 2 protein concentrations in the testis compared with SeY and SeNa. CONCLUSIONS: The optimal dietary Se dose for reproductive health of breeder roosters is 0.25-0.35 mg Se/kg, and SeNPs displayed better effects on reproductive health than SeNa and SeY in laying breeder roosters. The optimal doses and forms of Se maintain reproductive health of roosters associated with regulation intestinal microbiota homeostasis and/or testicular redox balance, inflammation, cell proliferation, and apoptosis.


Subject(s)
Gastrointestinal Microbiome , Selenium , Male , Animals , Testis/metabolism , Selenium/metabolism , Chickens/metabolism , Reproductive Health , Sperm Motility , Seeds , Oxidation-Reduction , Diet , Inflammation/metabolism , Apoptosis , Cell Proliferation , Dietary Supplements
5.
Langmuir ; 40(13): 6786-6805, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38503426

ABSTRACT

Traditional heterogeneous catalysts are affected in the catalytic hydrogenation of PS by the scale effect, viscosity effect, adhesion effect, and conformational effect, resulting in poor activity and stability. Monolithic Pd-CNTs@FN catalysts could eliminate or weaken the impact of these negative effects. We grew nitrogen-doped carbon nanotubes (NCNTs) on monolithic-foamed nickel (FN) and investigate their growth mechanism. Meanwhile, the feasibility of using the NCNTs@FN carrier for PS hydrogenation reaction was also verified. The growth of NCNTs on FN can be divided into 3 stages: initial growth stage, stable growth stage, and supersaturation stage. Finally, a three-layer structure of NCNT layer, dense carbon layer, and FN skeleton is formed. Two types of structures, nickel-doped carbon nanotubes (NiCNTs) and C-Ni alloy, are formed by combining C and Ni, while four nitrogen-doped structures, NPD, NPR, NG, and NO, are formed by C and N. The prepared carrier exhibited an extremely outstanding specific surface area (2.829 × 106 cm2/g) and strength (no NCNTs falling off after 24 h 500 rpm agitation), as well as high catalytic activity for PS hydrogenation after loaded with Pd (2.13 ± 0.95 nm), with a TOF of up to 27.6 gPS/(gPd•h). After 8 repetitions of the catalyst, there was no significant decrease in activity. This proves the excellent performance of Pd-NCNTs@FN in polymer hydrogenation reactions, laying a solid foundation for further research on the mechanism of NCNTs promoting PS hydrogenation and regulating the growth of NCNTs.

6.
Mol Cell Biochem ; 479(7): 1767-1786, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38485805

ABSTRACT

Indole-3-propionic acid (IPA), a gut microbiota-derived metabolite of tryptophan, has been proven to fulfill an essential function in cardiovascular disease (CVD) and nerve regeneration disease. However, the role of IPA in aortic dissection (AD) has not been revealed. We aimed to investigate the role of IPA in the pathogenesis of AD and the underlying mechanisms of IPA in endothelial dysfunction. Untargeted metabolomics has been employed to screen the plasma metabolic profile of AD patients in comparison with healthy individuals. Network pharmacology provides insights into the potential molecular mechanisms underlying IPA. 3-aminopropionitrile fumarate (BAPN) and angiotensin II (Ang II) were administered to induce AD in mice, while human umbilical vein endothelial cells (HUVECs) were employed for in vitro validation of the signaling pathways predicted by network pharmacology. A total of 224 potentially differential plasma metabolites were identified in the AD patients, with 110 up-regulated metabolites and 114 down-regulated metabolites. IPA was the most significantly decreased metabolite involved in tryptophan metabolism. Bcl2, caspase3, and AKT1 were predicted as the target genes of IPA by network pharmacology and molecular docking. IPA suppressed Ang II-induced apoptosis, intracellular ROS generation, inflammation, and endothelial tight junction (TJ) loss. Animal experiments demonstrated that administration of IPA alleviated the occurrence and severity of AD in mice. Taken together, we identified a previously unexplored association between tryptophan metabolite IPA and AD, providing a novel perspective on the underlying mechanism through which IPA mitigates endothelial dysfunction to protect against AD.


Subject(s)
Angiotensin II , Aortic Dissection , Human Umbilical Vein Endothelial Cells , Indoles , Metabolomics , Humans , Animals , Aortic Dissection/metabolism , Aortic Dissection/pathology , Aortic Dissection/drug therapy , Mice , Angiotensin II/metabolism , Male , Indoles/pharmacology , Human Umbilical Vein Endothelial Cells/metabolism , Female , Endothelium, Vascular/metabolism , Endothelium, Vascular/drug effects , Endothelium, Vascular/pathology , Apoptosis/drug effects , Mice, Inbred C57BL , Middle Aged
7.
Phys Chem Chem Phys ; 26(23): 16765-16773, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38819261

ABSTRACT

It is of great significance to search for new two-dimensional materials with excellent photocatalytic water splitting properties. Here, the AlOX (X = Cl, Br, or I) monolayers were constructed to explore their electronic and optical properties as a potential photocatalyst and mechanism of high photocatalytic activity by first principles calculations, for the first time. The results show that the AlOX (X = Cl, Br, or I) monolayers are all dynamically and thermodynamically stable. It is found that the AlOI monolayer exhibits visible optical absorption with a 538 nm absorption band edge, due to its direct band gap of 2.22 eV. Moreover, an appropriate band edge potential ensures its excellent reduction-oxidation (redox) ability. The asymmetry of crystals along different directions results in a noncoplanar HOMO and LUMO as well as an anisotropy effective mass and favors the separation of photogenerated carriers. These findings present the potential of the AlOX (X = Cl, Br, or I) monolayers as photocatalysts.

8.
Cell Mol Life Sci ; 80(8): 226, 2023 Jul 24.
Article in English | MEDLINE | ID: mdl-37486389

ABSTRACT

Insulin deficiency may be due to the reduced proliferation capacity of islet ß-cell, contributing to the onset of diabetes. It is therefore imperative to investigate the mechanism of the ß-cell regeneration in the islets. NKX6.1, one of the critical ß-cell transcription factors, is a pivotal element in ß-cell proliferation. The ubiquitin-binding enzyme 2C (UBE2C) was previously reported as one of the downstream molecules of NKX6.1 though the exact function and mechanism of UBE2C in ß-cell remain to be elucidated. Here, we determined a subpopulation of islet ß-cells highly expressing UBE2C, which proliferate actively. We also discovered that ß-cell compensatory proliferation was induced by UBE2C via the cell cycle renewal pathway in weaning and high-fat diet (HFD)-fed mice. Moreover, the reduction of ß-cell proliferation led to insulin deficiency in ßUbe2cKO mice and, therefore, developed type 2 diabetes. UBE2C was found to regulate PER1 degradation through the ubiquitin-proteasome pathway via its association with a ubiquitin ligase, CUL1. PER1 inhibition rescues UBE2C knockout-induced ß-cell growth inhibition both in vivo and in vitro. Notably, overexpression of UBE2C via lentiviral transduction in pancreatic islets was able to relaunch ß-cell proliferation in STZ-induced diabetic mice and therefore partially alleviated hyperglycaemia and glucose intolerance. This study indicates that UBE2C positively regulates ß-cell proliferation by promoting ubiquitination and degradation of the biological clock suppressor PER1. The beneficial effect of UBE2C on islet ß-cell regeneration suggests a promising application in treating diabetic patients with ß-cell deficiency.


Subject(s)
Diabetes Mellitus, Experimental , Diabetes Mellitus, Type 2 , Insulin-Secreting Cells , Islets of Langerhans , Animals , Mice , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Type 2/metabolism , Insulin/metabolism , Insulin-Secreting Cells/metabolism , Islets of Langerhans/metabolism , Ubiquitins
9.
Arch Toxicol ; 98(5): 1399-1413, 2024 May.
Article in English | MEDLINE | ID: mdl-38460002

ABSTRACT

Pulmonary fibrosis involves destruction of the lung parenchyma and extracellular matrix deposition. Effective treatments for pulmonary fibrosis are lacking and its pathogenesis is still unclear. Studies have found that epithelial-mesenchymal transition (EMT) of alveolar epithelial cells (AECs) plays an important role in progression of pulmonary fibrosis. Thus, an in-depth exploration of its mechanism might identify new therapeutic targets. In this study, we revealed that a novel circular RNA, MKLN1 (circMKLN1), was significantly elevated in two pulmonary fibrosis models (intraperitoneally with PQ, 50 mg/kg for 7 days, and intratracheally with BLM, 5 mg/kg for 28 days). Additionally, circMKLN1 was positively correlated with the severity of pulmonary fibrosis. Inhibition of circMKLN1 expression significantly reduced collagen deposition and inhibited EMT in AECs. EMT was aggravated after circMKLN1 overexpression in AECs. MiR-26a-5p/miR-26b-5p (miR-26a/b), the targets of circMKLN1, were confirmed by luciferase reporter assays. CircMKLN1 inhibition elevated miR-26a/b expression. Significantly decreased expression of CDK8 (one of the miR-26a/b targets) was observed after inhibition of circMKLN1. EMT was exacerbated again, and CDK8 expression was significantly increased after circMKLN1 inhibition and cotransfection of miR-26a/b inhibitors in AECs. Our research indicated that circMKLN1 promoted CDK8 expression through sponge adsorption of miR-26a/b, which regulates EMT and pulmonary fibrosis. This study provides a theoretical basis for finding new targets or biomarkers in pulmonary fibrosis.


Subject(s)
MicroRNAs , Pulmonary Fibrosis , Humans , Mice , Animals , Pulmonary Fibrosis/chemically induced , Pulmonary Fibrosis/genetics , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Circular/genetics , Alveolar Epithelial Cells , Epithelial-Mesenchymal Transition/genetics , Cyclin-Dependent Kinase 8/metabolism , Cell Adhesion Molecules/metabolism , Intracellular Signaling Peptides and Proteins/genetics , Intracellular Signaling Peptides and Proteins/metabolism
10.
Eur Spine J ; 2024 May 29.
Article in English | MEDLINE | ID: mdl-38809439

ABSTRACT

OBJECTIVE: This study was designed to investigate the clinical features, treatment modalities, and risk factors influencing neurological recovery in patients who underwent scoliosis correction with delayed postoperative neurological deficit (DPND). METHODS: Three patients with DPND were identified from 2 central databases for descriptive analysis. Furthermore, all DPND cases were retrieved from the PubMed and Embase databases. Neurological function recovery was categorized into complete and incomplete recovery groups based on the American Spinal Injury Association (ASIA) impairment scale. RESULTS: Two patients were classified as type 3, and one was classified as type 2 based on the MRI spinal cord classification. Intraoperative neurophysiological monitoring (IONM) was consistently negative throughout the corrective procedure, and intraoperative wake-up tests were normal. The average time to DPND development was 11.8 h (range, 4-18 h), and all three patients achieved complete recovery of neurological function after undergoing revision surgery. A total of 14 articles involving 31 patients were included in the literature review. The mean time to onset of DPND was found to be 25.2 h, and 85.3% (29/34) of patients experienced DPND within the first 48 h postoperatively, with the most common initial symptoms being decreased muscle strength and sensation (26 patients, 83.9%). Regarding neurological function recovery, 14 patients were able to reach ASIA grade E, while 14 patients were not able to reach ASIA grade E. Univariate analysis revealed that preoperative diagnosis (p = 0.004), operative duration (p = 0.017), intraoperative osteotomy method (p = 0.033), level of neurological deficit (p = 0.037) and deficit source (p = 0.0358) were significantly associated with neurological outcomes. Furthermore, multivariate regression analysis indicated a strong correlation between preoperative diagnosis (p = 0.003, OR, 68.633; 95% CI 4.299-1095.657) and neurological prognosis. CONCLUSION: Our findings indicate that spinal cord ischemic injury was a significant factor for patients experiencing DPND and distraction after corrective surgery may be a predisposing factor for spinal cord ischemia. Additionally, it is important to consider the possibility of DPND when limb numbness and decreased muscle strength occur within 48 h after corrective scoliosis surgery. Moreover, emergency surgical intervention is highly recommended for DPND caused by mechanical compression factors with a promising prognosis for neurological function, emphasizing the importance of taking into account preoperative orthopedic diagnoses when evaluating the potential for neurological recovery.

11.
BMC Med Educ ; 24(1): 86, 2024 Jan 24.
Article in English | MEDLINE | ID: mdl-38267919

ABSTRACT

BACKGROUND: Rain Classroom was one of the most popular online learning platforms in Chinese higher education during the pandemic. However, there is little research on user intention under the guidance of technology acceptance and unified theory (UTAUT). OBJECTIVE: This research aims to determine factors influencing students' behavioural intention to use Rain Classroom. METHODS: In this cross-sectional and correlational investigation, 1138 medical students from five medical universities in Guangxi Province, China, made up the sample. This study added self-efficacy (SE), motivation (MO), stress (ST), and anxiety (AN) to the UTAUT framework. This study modified the framework by excluding actual usage variables and focusing only on intention determinants. SPSS-26 and AMOS-26 were used to analyze the data. The structural equation modelling technique was chosen to confirm the hypotheses. RESULTS: Except for facilitating conditions (FC), all proposed factors, including performance expectancy (PE), effort expectancy (EE), social influence (SI), self-efficacy (SE), motivation (MO), anxiety (AN), and stress (ST), had a significant effect on students' behavioural intentions to use Rain Classroom. CONCLUSIONS: The research revealed that the proposed model, which was based on the UTAUT, is excellent at identifying the variables that influence students' behavioural intentions in the Rain Classroom. Higher education institutions can plan and implement productive classrooms.


Subject(s)
Intention , Students, Medical , Humans , China , Cross-Sectional Studies
12.
Diabetologia ; 66(4): 724-740, 2023 04.
Article in English | MEDLINE | ID: mdl-36538064

ABSTRACT

AIMS/HYPOTHESIS: Islets have complex heterogeneity and subpopulations. Cell surface markers representing alpha, beta and delta cell subpopulations are urgently needed for investigations to explore the compositional changes of each subpopulation in obesity progress and diabetes onset, and the adaptation mechanism of islet metabolism induced by a high-fat diet (HFD). METHODS: Single-cell RNA sequencing (scRNA-seq) was applied to identify alpha, beta and delta cell subpopulation markers in an HFD-induced mouse model of glucose intolerance. Flow cytometry and immunostaining were used to sort and assess the proportion of each subpopulation. Single-cell proteomics was performed on sorted cells, and the functional status of each alpha, beta and delta cell subpopulation in glucose intolerance was deeply elucidated based on protein expression. RESULTS: A total of 33,999 cells were analysed by scRNA-seq and clustered into eight populations, including alpha, beta and delta cells. For alpha cells, scRNA-seq revealed that the Ace2low subpopulation had downregulated expression of genes related to alpha cell function and upregulated expression of genes associated with beta cell characteristics in comparison with the Ace2high subpopulation. The impaired function and increased fragility of ACE2low alpha cells exposure to HFD was further suggested by single-cell proteomics. As for beta cells, the CD81high subpopulation may indicate an immature signature of beta cells compared with the CD81low subpopulation, which had robust function. We also found differential expression of Slc2a2 in delta cells and a potentially stronger cellular function and metabolism in GLUT2low delta cells than GLUT2high delta cells. Moreover, an increased proportion of ACE2low alpha cells and CD81low beta cells, with a constant proportion of GLUT2low delta cells, were observed in HFD-induced glucose intolerance. CONCLUSIONS/INTERPRETATION: We identified ACE2, CD81 and GLUT2 as surface markers to distinguish, respectively, alpha, beta and delta cell subpopulations with heterogeneous maturation and function. The changes in the proportion and functional status of islet endocrine subpopulations reflect the metabolic adaptation of islets to high-fat stress, which weakened the function of alpha cells and enhanced the function of beta and delta cells to bring about glycaemic homeostasis. Our findings provide a fundamental resource for exploring the mechanisms maintaining each islet endocrine subpopulation's fate and function in health and disease. DATA AVAILABILITY: The scRNA-seq analysis datasets from the current study are available in the Gene Expression Omnibus (GEO) repository under the accession number GSE203376.


Subject(s)
Glucose Intolerance , Insulin-Secreting Cells , Islets of Langerhans , Mice , Animals , Angiotensin-Converting Enzyme 2/metabolism , Glucose Intolerance/metabolism , Diet, High-Fat , Insulin/metabolism , Proteomics , Islets of Langerhans/metabolism , Insulin-Secreting Cells/metabolism , Sequence Analysis, RNA
13.
J Am Chem Soc ; 145(5): 3187-3195, 2023 Feb 08.
Article in English | MEDLINE | ID: mdl-36700656

ABSTRACT

Supramolecular host-guest ferroelectrics based on solution processing are highly desirable because they are generally created with intrinsic piezoelectricity/ferroelectricity and do not need further poling. Poly(vinylidene fluoride) (PVDF) in the electric-active beta phase after stretching/annealing still shows no piezoelectric response unless poled. Although many supramolecular host-guest ferroelectrics have been discovered, their piezoelectricity is relatively small. Based on H/F substitution, we reported a supramolecular host-guest compound [(CF3-C6H4-NH3)(18-crown-6)][TFSA] (CF3-C6H4-NH3 = 4-trifluoromethylanilinium, TFSA = bis(trifluoromethanesulfonyl)ammonium) with a remarkable piezoelectric response of 42 pC/N under no poling condition. The introduction of F atoms increases phase transition temperature, polar axes, second harmonic generation (SHG) intensity, and piezoelectric coefficient d33. To our knowledge, such a large piezoelectric performance of [(CF3-C6H4-NH3)(18-crown-6)][TFSA] makes its d33, piezoelectric voltage coefficient g33, and mechanical quality factor Qm the highest among the reported supramolecular host-guest ferroelectric compounds and even larger than the values of PVDF. This work provides inspiration for optimizing piezoelectricity on molecular materials.

14.
J Am Chem Soc ; 145(8): 4892-4899, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36795554

ABSTRACT

Metal-free perovskites with light weight and eco-friendly processability have received great interest in recent years due to their superior physical features in ferroelectrics, X-ray detection, and optoelectronics. The famous metal-free perovskite ferroelectric MDABCO-NH4-I3 (MDABCO = N-methyl-N'-diazabicyclo[2.2.2]octonium) has been demonstrated to exhibit excellent ferroelectricity comparable to that of inorganic ceramic ferroelectric BaTiO3, such as large spontaneous polarization and high Curie temperature (Ye et al. Science 2018, 361, 151). However, piezoelectricity as a vitally important index is far from enough in the metal-free perovskite family. Here, we report the discovery of large piezoelectric response in a new metal-free three-dimensional perovskite ferroelectric NDABCO-NH4-Br3 (NDABCO = N-amino-N'-diazabicyclo[2.2.2]octonium) by replacing the methyl group of MDABCO with the amino group. Besides the evident ferroelectricity, strikingly, NDABCO-NH4-Br3 shows a large d33 of 63 pC/N more than 4 times that of MDABCO-NH4-I3 (14 pC/N). The d33 value is also strongly supported by the computational study. To the best of our knowledge, such a large d33 value ranks the highest among the documented organic ferroelectric crystals to date and represents a major breakthrough in metal-free perovskite ferroelectrics. Combined with decent mechanical properties, NDABCO-NH4-Br3 is expected to be a competitive candidate for medical, biomechanical, wearable, and body-compatible ferroelectric devices.

15.
J Am Chem Soc ; 145(42): 23292-23299, 2023 Oct 25.
Article in English | MEDLINE | ID: mdl-37819908

ABSTRACT

Fullerenes offer versatile functionalities and are promising materials for a widespread range of applications from biomedicine and energy to electronics. Great efforts have been made to manipulate the symmetries of fullerene and its derivatives for studying material properties and novel effects, such as ferroelectricity with polar symmetry; however, no documentary report has been obtained to realize their ferroelectricity. Here, for the first time, we demonstrated clear ferroelectricity in a fullerene adduct formed by C60 and S8. More is different: the combination of the most symmetric molecule C60 with the highest Ih symmetry and molecule S8 with high D4d symmetry resulted in the polar C60S8 adduct with a low crystallographic symmetry of the C2v (mm2) point group at room temperature. The presented C60S8 undergoes polar-to-polar ferroelectric phase transition with the mm2Fm notation, whose ferroelectricity was confirmed by a ferroelectric hysteresis loop and ferroelectric domain switching. This finding opens up a new functionality for fullerenes and sheds light on the exploration of more ferroelectric fullerenes.

16.
J Am Chem Soc ; 145(3): 1936-1944, 2023 Jan 25.
Article in English | MEDLINE | ID: mdl-36637030

ABSTRACT

Piezoelectric materials that enable electromechanical conversion have great application value in actuators, transducers, sensors, and energy harvesters. Large piezoelectric (d33) and piezoelectric voltage (g33) coefficients are highly desired and critical to their practical applications. However, obtaining a material with simultaneously large d33 and g33 has long been a huge challenge. Here, we reported a hybrid perovskite ferroelectric [Me3NCH2Cl]CdBrCl2 to mitigate and roughly address this issue by heavy halogen substitution. The introduction of a large-size halide element softens the metal-halide bonds and reduces the polarization switching barrier, resulting in excellent piezoelectric response with a large d33 (∼440 pC/N), which realizes a significant optimization compared with that of previously reported [Me3NCH2Cl]CdCl3 (You et al. Science2017, 357, 306-309). More strikingly, [Me3NCH2Cl]CdBrCl2 simultaneously shows a giant g33 of 6215 × 10-3 V m/N, far exceeding those of polymers and conventional piezoelectric ceramics. Combined with simple solution preparation, easy processing of thin films, and a high Curie temperature of 373 K, these attributes make [Me3NCH2Cl]CdBrCl2 promising for high-performance piezoelectric sensors in flexible, wearable, and biomechanical devices.

17.
J Med Virol ; 95(12): e29339, 2023 12.
Article in English | MEDLINE | ID: mdl-38130177

ABSTRACT

Norovirus (NoV) infection is a leading cause of acute gastroenteritis (AGE) for people of all ages. Here, we reported the molecular epidemiology and genetic diversity of NoVs among hospitalized patients with AGE between 2016 and 2018 in Shandong Province, China. Two thousand sixty-nine AGE patients from sentinel hospitals were enrolled. The stool samples were collected and tested for NoVs by real-time RT-PCR. The RNA-dependent RNA polymerase (RdRp) and capsid gene of 163 strains were amplified and sequenced for genotyping. Phylogenetic analyses and genomic characterization were conducted with the VP1 and RdRp region of the full genome sequences. Four hundred seventy two (21.76%) samples were NoV-positive. The positive rate in 2016 was higher than those of 2017 and 2018. We observed diverse NoV genotypes. GII.2[P16] emerged in January 2017 and became the dominant genotype between May and June 2017. Phylogenetic analyses showed that our GII.2[P16] genomes clustered in the SC1 in VP1 region, while they belonged to the Emerging GⅡ.P16 (2015-2017) clade in RdRp region. Our GⅡ.4 strains displayed two amino acid mutations, positions R297H and D372N, in epitope A of the VP1 region. Our study highlighted that NoV is an important pathogen of viral AGE in Shandong and, therefore, it is necessary to strengthen its surveillance.


Subject(s)
Caliciviridae Infections , Gastroenteritis , Norovirus , Humans , Norovirus/genetics , Molecular Epidemiology , Phylogeny , Prevalence , Gastroenteritis/epidemiology , Genotype , Mutation , China/epidemiology , Caliciviridae Infections/epidemiology , RNA-Dependent RNA Polymerase/genetics , Feces , Genetic Variation
18.
J Nutr ; 153(1): 47-55, 2023 01.
Article in English | MEDLINE | ID: mdl-36913478

ABSTRACT

BACKGROUND: Nutritional muscular dystrophy (NMD) in animals is induced by dietary selenium (Se) deficiency. OBJECTIVES: This study was conducted to explore the underlying mechanism of Se deficiency-induced NMD in broilers. METHODS: One-day-old male Cobb broilers (n = 6 cages/diet, 6 birds/cage) were fed a Se-deficient diet (Se-Def, 47 µg Se/kg) or the Se-Def supplemented with 0.3 mg Se/kg (control) for 6 wk. Thigh muscles of broilers were collected at week 6 for measuring Se concentration, histopathology, and transcriptome and metabolome assays. The transcriptome and metabolome data were analyzed with bioinformatics tools and other data were analyzed with Student's t tests. RESULTS: Compared with the control, Se-Def induced NMD in broilers, including reduced (P < 0.05) final body weight (30.7%) and thigh muscle size, reduced number and cross-sectional area of fibers, and loose organization of muscle fibers. Compared with the control, Se-Def decreased (P < 0.05) the Se concentration in the thigh muscle by 52.4%. It also downregulated (P < 0.05) GPX1, SELENOW, TXNRD1-3, DIO1, SELENOF, H, I, K, M, and U by 23.4-80.3% in the thigh muscle compared with the control. Multi-omics analyses indicated that the levels of 320 transcripts and 33 metabolites were significantly altered (P < 0.05) in response to dietary Se deficiency. Integrated transcriptomics and metabolomics analysis revealed that one-carbon metabolism, including the folate and methionine cycle, was primarily dysregulated by Se deficiency in the thigh muscles of broilers. CONCLUSIONS: Dietary Se deficiency induced NMD in broiler chicks, potentially with the dysregulation of one-carbon metabolism. These findings may provide novel treatment strategies for muscle disease.


Subject(s)
Muscular Dystrophies , Selenium , Animals , Male , Selenium/metabolism , Chickens/metabolism , Antioxidants/metabolism , Dietary Supplements , Diet/veterinary , Carbon/metabolism , Animal Feed/analysis
19.
J Nutr ; 153(12): 3373-3381, 2023 12.
Article in English | MEDLINE | ID: mdl-37923224

ABSTRACT

BACKGROUND: Heat stress (HS) has a harmful impact on the male reproductive system, primarily by reducing the sperm quality. The testicular microenvironment plays an important role in sperm quality. OBJECTIVES: This study aimed to explore the underlying mechanism by which HS impairs the male reproductive system through the testicular microenvironment. METHODS: Ten-week-old male mice (n = 8 mice/group) were maintained at a normal temperature (25°C, control) or subjected to HS (38°C for 2 h each day, HS) for 2 wk. The epididymides and testes were collected at week 2 to determine sperm quality, histopathology, retinol concentration, the expression of retinol metabolism-related genes, and the testicular microbiome. The testicular microbiome profiles were analyzed using biostatistics and bioinformatics; other data were analyzed using a 2-sided Student's t test. RESULTS: Compared with the control, HS reduced (P < 0.05) sperm count (42.4%) and motility (97.7%) and disrupted the integrity of the blood-testis barrier. Testicular microbial profiling analysis revealed that HS increased the abundance of the genera Asticcacaulis, Enhydrobacter, and Stenotrophomonas (P < 0.05) and decreased the abundance of the genera Enterococcus and Pleomorphomonas (P < 0.05). Notably, the abundance of Asticcacaulis spp. showed a significant negative correlation with sperm count (P < 0.001) and sperm motility (P < 0.001). Moreover, Asticcacaulis spp. correlated significantly with most blood differential metabolites, particularly retinol (P < 0.05). Compared with the control, HS increased serum retinol concentrations (25.3%) but decreased the testis retinol concentration by 23.7%. Meanwhile, HS downregulated (P < 0.05) the expression of 2 genes (STRA6 and RDH10) and a protein (RDH10) involved in retinol metabolism by 27.3%-36.6% in the testis compared with the control. CONCLUSIONS: HS reduced sperm quality, mainly because of an imbalance in the testicular microenvironment potentially caused by an increase in Asticcacaulis spp. and disturbed retinol metabolism. These findings may offer new strategies for improving male reproductive capacity under HS.


Subject(s)
Testis , Vitamin A , Male , Mice , Animals , Testis/metabolism , Vitamin A/metabolism , Sperm Motility , Semen , Spermatozoa/metabolism , Spermatozoa/pathology , Heat-Shock Response
20.
Soft Matter ; 19(28): 5244-5248, 2023 Jul 19.
Article in English | MEDLINE | ID: mdl-37403976

ABSTRACT

Here we provide a novel method for fabricating a pH- and thermal-responsive triple-shape memory hydrogel based on a single reversible switch phase. A high-density quadruple hydrogen-bonding ureido-pyrimidinone (UPy) system was introduced into the hydrogel network, which can occur to varied degrees of dissociation under different pH and temperature conditions. Different degrees of dissociation and reassociation can be viewed as different subsets of memory elements to freeze and unfreeze the temporary shapes. Although this class of hydrogels contains only a single transition phase, they feature a large dissociative differential in response to varied external stimuli to provide multiple windows for programming different temporary shapes.

SELECTION OF CITATIONS
SEARCH DETAIL