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1.
Small ; : e2310768, 2024 Feb 11.
Article in English | MEDLINE | ID: mdl-38342671

ABSTRACT

There is a noticeable gap in the literature regarding research on halogen-substitution-regulated ferroelectric semiconductors featuring multiple phase transitions. Here, a new category of 1D perovskite ferroelectrics (DFP)2 SbX5 (DFP+ = 3,3-difluoropyrrolidium, X- = I- , Br- , abbreviated as I-1 and Br-2) with twophase transitions (PTs) is reported. The first low-temperature PT is a mmmFmm2 ferroelectric PT, while the high-temperature PT is a counterintuitive inverse temperature symmetry-breaking PT. By the substitution of iodine with bromine, the Curie temperature (Tc) significantly increases from 348 K of I-1 to 374 K of Br-2. Their ferroelectricity and pyroelectricity are improved (Ps value from 1.3 to 4.0 µC cm-2 , pe value from 0.2 to 0.48 µC cm-2  K-1 for I-1 and Br-2), while their optical bandgaps increased from 2.1 to 2.7 eV. A critical slowing down phenomenon is observed in the dielectric measurement of I-1 while Br-2 exhibits the ferroelastic domain. Structural and computational analyses elucidate that the order-disorder movement of cations and the distortion of the chain perovskite [SbX5 ]2- anions skeleton lead to PT. The semiconductor properties are determined by [SbX5 ]2- anions. The findings contribute to the development of ferroelectric semiconductors and materials with multiple PTs and provide materials for potential applications in the optoelectronic field.

2.
Mol Reprod Dev ; 90(2): 87-97, 2023 02.
Article in English | MEDLINE | ID: mdl-36598871

ABSTRACT

Mouse germinal vesicle (GV) oocytes are divided into surrounded nucleolus (SN) and nonsurrounded nucleolus (NSN) oocytes based on chromatin morphology. NSN oocytes spontaneously transform into SN oocytes after accumulating enough maternal transcripts. SN oocytes show transcriptional silencing. When oocyte maturation is abnormal or takes place in vitro, NSN oocytes do not go through SN stage before proceeding to MII. Nontransitive oocytes show developmental retardation, a low fertilization rate, and arrest at the two-cell embryo stage in mice. Here, chromatin-binding ribonucleic acid polymerase II (RNAP II) activity, newly synthesized RNA, and chromatin accessibility in GV oocytes were examined. In SN oocytes, RNAP II did not bind to DNA, neo-RNA was not generated in nuclei, and the phosphorylation state of RNAP II did not affect the chromatin-binding activity. The number of accessible genes in SN oocytes was remarkably lower than that in NSN oocytes. The accessibility of different functional genes was also different between the two types of oocytes. Thus, low chromatin accessibility leads to transcriptional silencing in SN oocytes.


Subject(s)
Chromatin Immunoprecipitation Sequencing , Chromatin , Animals , Mice , Chromatin/metabolism , Oocytes/metabolism , Oogenesis/genetics , Cell Nucleolus/metabolism
3.
Inorg Chem ; 62(10): 4181-4187, 2023 Mar 13.
Article in English | MEDLINE | ID: mdl-36848219

ABSTRACT

Hybrid organic-inorganic ferroelectrics (HOIFs) have a wide range of applications in the optoelectronic field in terms of rich optoelectronic properties. Particularly, lead-free HOIFs have attracted extensive attention due to their environmental friendliness, low heavy metal toxicity, and low synthesis cost. However, there are few reports about Zn-based HOIFs due to their uncontrollable ferroelectric synthesis and other reasons. Here, we designed and synthesized a zinc-based zero-dimensional (3,3-difluoropyrrolidine)2ZnCl4·H2O (DFZC) single crystal, which undergoes a phase transition from ferroelectric to paraelectric phase (space group from Pna21 to Pnma) at 295.5 K/288.9 K during the heating/cooling process. The systematic study shows that the ferroelectric phase transition is a displacive type. The ferroelectric hysteresis loop of DFZC was obtained by the double-wave method and the Sawyer-Tower method, which has a spontaneous polarization (Ps) of ∼0.4 µC/cm2. This work reveals the strategy to design new zinc-based lead-free HOIFs for potential applications in optoelectronic fields.

4.
Cell Biol Toxicol ; 39(6): 3255-3267, 2023 12.
Article in English | MEDLINE | ID: mdl-37768392

ABSTRACT

Anthracycline antitumor agents, such as doxorubicin (DOX), are effective in the treatment of solid tumors and hematological malignancies, but anthracycline-induced cardiotoxicity (AIC) limits their application as chemotherapeutics. Dexrazoxane (DEX) has been adopted to prevent AIC. Using a chronic AIC mouse model, we demonstrated that DEX is insufficient to reverse DOX-induced cardiotoxicity. Although therapies targeting autophagy have been explored to prevent AIC, but whether novel autophagy inhibitors could alleviate or prevent AIC in clinically relevant models needs further investigation. Here, we show that genetic ablation of Atg7, a key regulator in the early phase of autophagy, protected mice against AIC. We further demonstrated that SAR405, a novel autophagy inhibitor, attenuated DOX-induced cytotoxicity. Intriguingly, the combination of DEX and SAR405 protected cells against DOX-induced cardiotoxicity in vivo. Using the cardiomyocyte cell lines AC16 and H9c2, we determined that autophagy was initiated during AIC. Our results suggest that inhibition of autophagy at its early phase with SAR405 combined with DEX represents an effective therapeutic strategy to prevent AIC.


Subject(s)
Cardiotoxicity , Doxorubicin , Mice , Animals , Cardiotoxicity/drug therapy , Cardiotoxicity/etiology , Cardiotoxicity/prevention & control , Doxorubicin/pharmacology , Antibiotics, Antineoplastic/toxicity , Antibiotics, Antineoplastic/metabolism , Myocytes, Cardiac/metabolism , Anthracyclines/metabolism , Anthracyclines/pharmacology , Anthracyclines/therapeutic use , Autophagy , Apoptosis , Oxidative Stress
5.
Opt Express ; 30(12): 22051-22065, 2022 Jun 06.
Article in English | MEDLINE | ID: mdl-36224912

ABSTRACT

The orientation of a single molecule provides valuable information on fundamental biological processes. We report a technique for the simultaneous estimation of single-molecule 2D position and 2D orientation with ultra-high localization precision (∼2-nm precision with ∼500 photons under a typical 100-nm diameter of excitation beam pattern), which is also compatible with tracking in living cells. In the proposed method, the theoretical precision limits are calculated, and the localization and orientation performance along with potential applications are explored using numerical simulations. Compared to other camera-based orientation measurement methods, it is confirmed that the proposed method can obtain reasonable estimates even under very weak signals (∼15 photons). Moreover, the maximum likelihood estimator (MLE) is found to converge to the theoretical limit when the total number of photons is less than 100.


Subject(s)
Nanotechnology , Photons
6.
Opt Express ; 30(26): 46849-46860, 2022 Dec 19.
Article in English | MEDLINE | ID: mdl-36558626

ABSTRACT

A novel super-resolution imaging technique based on the minimum photon flux (MINFLUX), can achieve nanometer-scale localization precision and sub-5-nm imaging. However, aberrations can affect the localization performance and degrade the quality of reconstructed images. In this study, we analyze the effects of different low-order aberrations on the MINFLUX system through both theoretical limits and Monte Carlo methods. We report that 1) defocus and spherical aberration have little effect on 2D localization performance, whereas astigmatism and coma have significant negative effects; 2) system aberrations that can be measured in advance cause changes primarily in the magnitude and angular uniformity of localization precision, whereas sample-induced aberrations that cannot be a priori introduce large biases and reduce localization accuracy.

7.
Inorg Chem ; 60(22): 17212-17218, 2021 Nov 15.
Article in English | MEDLINE | ID: mdl-34734704

ABSTRACT

Organic-inorganic hybrid ferroelectrics (OIHFs) have fueled enormous interest benefiting from their less environmental pollution, performance-tailored functionality, low product costs as well as tunability of structures. However, the lack of material synthesis approaches and diverse targeted molecular design is a stumbling block for designing novel OIHFs rationally. Here, we report a unique organic-inorganic hybrid ferroelectric (3,3-difluoropyrrolidine)2CdCl4 1 and another novel nonferroelectric crystal (3,3-difluoropyrrolidine)2Cd2Cl6 2 by changing various crystallization solvents. Significantly, 1 presents a ferroelectric phase transition behavior at ∼367 K, and the distinct symmetry breaking, i.e., mmmFm, sets up a biaxial ferroelectric with four equivalent directions of polarization, which has a Pr ∼ 0.77 µC/cm2. Systematic studies prove that ferroelectricity can be ascribed to the synergistic effects of the distortion of the inorganic anion skeleton and the ordering of organic cations. This work reveals the potential of constructing novel ferroelectrics based on the solvent selective effect and pyrrolidinium as organic cations.

8.
J Environ Sci (China) ; 101: 145-155, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33334510

ABSTRACT

The organic-inorganic hybrid halide compounds have emerged as one of the most promising photoelectric material for their superior optoelectronic properties and hold great prospects for renewable energy substitutes and environmental protection as photocatalysis. Here, we report the optical properties of the Sb-based organic-inorganic hybrid ferroelectric materials: pyridine-4-aminium tetrachloroantimonate ((C5H7N2)SbCl4, sample 1), piperidin-1-aminium tetrachloroantimonate ((C5H13N2)SbCl4, sample 2) and tris(trimethylammonium) nonachlorodiantimonate (((CH3)3NH)3Sb2Cl9, sample 3), which are a kind of exploited efficient photocatalysts. Samples 2 and 3 exhibit distinct photoelectric respond, which are mainly ascribed to their minor narrow band-gap compared with sample 1. For the ferroelectrics, the intrinsic of spontaneous polarization of sample 3 at room temperature is favourable for the separation of photogenerated electrons and holes within the photorespond process. Moreover, sample 3 shows the highest efficiency of photo-decomposed Rhodamine B (90.2% within 80 min) and Methyl Orange (MO) (97.4% within 50 min), thanks to the photo-excited electrons and holes promoting the formation of oxidative radical species during the photo-redox progress. These findings prove that the development of a novel Sb-based organic-inorganic hybrid halide compounds with good stability in the degradation of organic dyes paves a way to designing new photocatalyst.


Subject(s)
Coloring Agents , Electrons , Catalysis , Oxidation-Reduction
9.
J Cell Physiol ; 234(11): 19574-19581, 2019 11.
Article in English | MEDLINE | ID: mdl-30980384

ABSTRACT

Juglone, a naphthoquinone isolated from many species of the Juglandaceae family, has been used in traditional Chinese medicine for centuries because of its antiviral, antibacterial, and antitumor activities. However, the toxicity of juglone has also been demonstrated. Here, we used porcine oocytes as a model to explore the effects of juglone on oocyte maturation and studied the impact of vitamin C (VC) administration on juglone exposure-induced meiosis defects. Exposure to juglone significantly restricted cumulus cell expansion and decreased the first polar body extrusion. In addition, juglone exposure disturbed spindle organization, actin assembly, and the distribution of mitochondria during oocyte meiosis, while the acetylation level of α-tubulin was also reduced. These defects were all ameliorated by VC administration. Our findings indicate that juglone exposure induced meiotic failure in porcine oocytes, while VC protected against these defects during porcine oocyte maturation by ameliorating the organization of the cytoskeleton and mitochondrial distribution.


Subject(s)
Ascorbic Acid/pharmacology , Meiosis/drug effects , Naphthoquinones/adverse effects , Oocytes/drug effects , Acetylation/drug effects , Animals , Cumulus Cells/drug effects , Cumulus Cells/pathology , Cytoskeleton/drug effects , Cytoskeleton/pathology , Female , In Vitro Oocyte Maturation Techniques , Mitochondria/drug effects , Mitochondria/pathology , Naphthoquinones/pharmacology , Oocytes/pathology , Polar Bodies/drug effects , Polar Bodies/pathology , Swine , Tubulin/genetics
10.
Mikrochim Acta ; 186(12): 843, 2019 11 25.
Article in English | MEDLINE | ID: mdl-31768709

ABSTRACT

Voltammetric detection of the K-ras gene fragment was accomplished through the combined application of (a) a switchable DNA nanostructure, (b) the use of hairpin probe and exonuclease III (Exo III)-assisted signal amplification, (c) a split G-quadruplex, and (d) by exploiting the redox activity of DNAzyme. Three assistant oligonucleotides were designed to construct a DNA tweezer on a gold electrode. It is in "open state" in the absence of K-ras DNA. Then, a hairpin probe was introduced, whose stem-loop structure can be opened through hybridization with the K-ras DNA. Exo III is added which hydrolyzes the complementary region of the hairpin sequence to release a single-stranded rest fragment. The ssDNA hybridizes with the DNA tweezer on the electrode which thereby is switched to the "closed state". This leads to the formation of G-quadruplex due to the shortened distance of the split G-quadruplex-forming sequences in the tweezer. The voltammetric signal of the G-quadruplex-hemin complex, with a peak near -0.3 V vs. Ag/AgCl, is used as the signal output. Under the optimal conditions, the current response in differential pulse voltammetry (DPV) increases linearly with the concentration of K-ras DNA in the range of 0.01-1000 pM, and the detection limit is 2.4 fM. The assay can clearly discriminate K-ras DNA from a single-base mutation. The method has excellent selectivity and was applied to the determination of K-ras DNA in (spiked) serum samples. Graphical abstractSchematic representation of a method for the determination of the K-ras gene fragment through a combination of switchable DNA tweezer, split G-quadruplex, and exonuclease III (ExoIII)-assisted target recycling signal amplification.


Subject(s)
Biosensing Techniques/methods , DNA/blood , Electrochemical Techniques/methods , Genes, ras , Nanostructures/chemistry , Oligodeoxyribonucleotides/chemistry , Base Sequence , DNA/genetics , Electrochemical Techniques/instrumentation , Electrodes , G-Quadruplexes , Gold/chemistry , Hemin/chemistry , Humans , Inverted Repeat Sequences , Limit of Detection , Mutation , Nucleic Acid Hybridization , Oligodeoxyribonucleotides/genetics
11.
Gastroenterology ; 153(5): 1429-1443.e5, 2017 11.
Article in English | MEDLINE | ID: mdl-28764929

ABSTRACT

BACKGROUND & AIMS: Induction of nonapoptotic cell death could be an approach to eliminate apoptosis-resistant tumors. We investigated necroptosis-based therapies in mouse models of pancreatic ductal adenocarcinoma cancer (PDAC). METHODS: We screened 273 commercially available kinase inhibitors for cytotoxicity against a human PDAC cell line (PANC1). We evaluated the ability of the aurora kinase inhibitor CCT137690 to stimulate necroptosis in PDAC cell lines (PANC1, PANC2.03, CFPAC1, MiaPaCa2, BxPc3, and PANC02) and the HEK293 cell line, measuring loss of plasma membrane integrity, gain in cell volume, swollen organelles, and cytoplasmic vacuoles. We tested the effects of CCT137690 in colon formation assays, and the effects of the necroptosis (necrostatin-1 and necrosulfonamide), apoptosis, autophagy, and ferroptosis inhibitors. We derived cells from tumors that developed in Pdx1-Cre;K-RasG12D/+;p53R172H/+ (KPC) mice. Genes encoding proteins in cell death pathways were knocked out, knocked down, or expressed from transgenes in PDAC cell lines. Athymic nude or B6 mice were given subcutaneous injections of PDAC cells or tail-vein injections of KPC tumor cells. Mice were given CCT137690 (80 mg/kg) or vehicle and tumor growth was monitored; tumor tissues were collected and analyzed by immunohistochemistry. We compared gene expression levels between human pancreatic cancer tissues (n = 130) with patient survival times using the online R2 genomics analysis and visualization platform. RESULTS: CCT137690 induced necrosis-like death in PDAC cell lines and reduced colony formation; these effects required RIPK1, RIPK3, and MLKL, as well as inhibition of aurora kinase A (AURKA). AURKA interacted directly with RIPK1 and RIPK3 to reduce necrosome activation. AURKA-mediated phosphorylation of glycogen synthase kinase 3 beta (GSK3ß) at serine 9 inhibited activation of the RIPK3 and MLKL necrosome. Mutations in AURKA (D274A) or GSK3ß (S9A), or pharmacologic inhibitors of RIPK1 signaling via RIPK3 and MLKL, reduced the cytotoxic activity of CCT137690 in PDAC cells. Oral administration of CCT137690 induced necroptosis and immunogenic cell death in subcutaneous and orthotopic tumors in mice, and reduced tumor growth and tumor cell phosphorylation of AURKA and GSK3ß. CCT137690 increased survival times of mice with orthotopic KPC PDACs and reduced tumor growth, stroma, and metastasis. Increased expression of AURKA and GSK3ß mRNAs associated with shorter survival times of patients with pancreatic cancer. CONCLUSIONS: We identified the aurora kinase inhibitor CCT137690 as an agent that induces necrosis-like death in PDAC cells, via RIPK1, RIPK3, and MLKL. CCT137690 slowed growth of orthotopic tumors from PDAC cells in mice, and expression of AURKA and GSK3ß associate with patient survival times. AURKA might be targeted for treatment of pancreatic cancer.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Aurora Kinase A/antagonists & inhibitors , Carcinoma, Pancreatic Ductal/drug therapy , Imidazoles/pharmacology , Pancreatic Neoplasms/drug therapy , Protein Kinase Inhibitors/pharmacology , Pyridines/pharmacology , Animals , Aurora Kinase A/genetics , Aurora Kinase A/metabolism , Carcinoma, Pancreatic Ductal/enzymology , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/pathology , Cell Line, Tumor , Dose-Response Relationship, Drug , Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Neoplastic , HEK293 Cells , Humans , Mice, Nude , Mice, Transgenic , Necrosis , Pancreatic Neoplasms/enzymology , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Signal Transduction/drug effects , Time Factors , Xenograft Model Antitumor Assays
12.
Zhongguo Dang Dai Er Ke Za Zhi ; 18(7): 635-8, 2016 Jul.
Article in Zh | MEDLINE | ID: mdl-27412548

ABSTRACT

OBJECTIVE: To investigate the influence of delayed cord clamping (DCC) on preterm infants with a gestational age of <32 weeks. METHODS: Ninety preterm infants with a gestational age of <32 weeks delivered naturally from January to December, 2015 were enrolled and randomly divided into DCC group (46 infants) and immediate cord clamping (ICC) group (44 infants). The routine blood test results, total amount of red blood cell transfusion, blood gas parameters, mean arterial pressure, bilirubin peak, total time of phototherapy, and incidence rates of necrotizing enterocolitis, late-onset sepsis, intracranial hemorrhage, retinopathy, and bronchopulmonary dysplasia were compared between the two groups. RESULTS: Compared with the ICC group, the DCC group had significantly higher levels of hemoglobin, hematocrit, mean arterial pressure, and standard base excess (P<0.05), as well as a significantly lower percentage of preterm infants who underwent volume expansion and dopamine treatment and a significantly lower amount of red blood cell transfusion (P<0.05). The body temperature, pH value, HCO3(-) concentration, serum bilirubin peak, total time of phototherapy, and incidence rates of late-onset sepsis, retinopathy, grade≥2 intracranial hemorrhage, and grade≥2 neonatal necrotizing enterocolitis showed no significant differences between the two groups (P>0.05). CONCLUSIONS: DCC is a safe clinical intervention and can improve the prognosis of preterm infants with a gestational age of <32 weeks.


Subject(s)
Delivery, Obstetric/methods , Infant, Newborn/blood , Umbilical Cord/blood supply , Constriction , Female , Gestational Age , Humans , Infant, Premature , Male , Time Factors
13.
iScience ; 27(1): 108691, 2024 Jan 19.
Article in English | MEDLINE | ID: mdl-38205254

ABSTRACT

Tumors maintain an alkaline intracellular environment to enable rapid growth. The proton exporter NHE1 participates in maintenance of this pH gradient. However, whether targeting NHE1 could inhibit the growth of tumor cells remains unknown. Here, we report that the NHE1 inhibitor Hexamethylene amiloride (HA) efficiently suppresses the growth of AML cell lines. Moreover, HA combined with venetoclax synergized to efficiently inhibit the growth of AML cells. Interestingly, lysosomes are the main contributors to the synergism of HA and venetoclax in inhibiting AML cells. Most importantly, the combination of HA and venetoclax also had prominent anti-leukemia effects in both xenograft models and bone marrow samples from AML patients. In summary, our results provide evidence that the NHE1 inhibitor HA or its combination with venetoclax efficiently inhibits the growth of AML in vitro and in vivo.

14.
Environ Sci Pollut Res Int ; 30(22): 62803-62814, 2023 May.
Article in English | MEDLINE | ID: mdl-36949372

ABSTRACT

Particle shape greatly influences the mechanical behavior of geotechnical materials. For a specific material, for example, a sand particle, it remains an open question how to provide a comprehensive quantitative information about the particle shape. While Fourier descriptors, as a sequence of good shape descriptors, are well addressed in the literature, approaches mainly aim at pattern recognition in the field of computer vision. In this paper, Fourier descriptors are used to analyze the particle shape of geotechnical material. A total of 600 sand particles were collected from the Hutuo River, the main water resource of Shijiazhuang County, Hebei Province. Several shape descriptors, elongation, circularity, convexity, and roughness, are identified and further analyzed statistically. The Andrews plot of Fourier descriptors can be used to discriminate the sand samples. And it is convenient to use Fourier descriptors to reconstruct sand particles. A functional relationship between Fourier descriptors Dk and k, the frequency of the kth components is proved to exist. Moreover, the relationship between shape descriptors and Fourier descriptors is investigated in a correlation analysis. The elongation has a moderate correlation with Fourier descriptors of D1.


Subject(s)
Biometry , Sand
15.
Toxicology ; 490: 153512, 2023 05 15.
Article in English | MEDLINE | ID: mdl-37062353

ABSTRACT

Anthracycline antineoplastics are effective in the treatment of hematological malignancies and solid tumors. However, the anthracycline-induced cardiotoxicity (AIC) limits their use as chemotherapeutic agents. Autophagy-based therapies have been explored to prevent AIC. Yet, whether inhibition of autophagy during its early stage could alleviate AIC remains unclear. In this study, we firstly observed the activation of autophagy during AIC in both cardiomyocyte cell lines AC16 and H9c2. Moreover, knockdown of Atg7, a key regulatory factor in early autophagy, could ameliorate the effects of DOX-induced AIC. Importantly, the use of early autophagy inhibitor 3-MA protected cardiomyocyte cells from DOX-induced cardiotoxicity in vitro and in a chronic AIC mouse model. Our findings demonstrate that inhibiting early stage of autophagy may be an effective preventative therapeutic strategy to protect cardiac function from AIC.


Subject(s)
Cardiotoxicity , Doxorubicin , Mice , Animals , Cardiotoxicity/metabolism , Doxorubicin/toxicity , Antibiotics, Antineoplastic/toxicity , Myocytes, Cardiac , Autophagy , Anthracyclines/metabolism , Anthracyclines/pharmacology , Anthracyclines/therapeutic use , Oxidative Stress , Apoptosis
16.
Int J Numer Method Biomed Eng ; 39(10): e3664, 2023 10.
Article in English | MEDLINE | ID: mdl-36447341

ABSTRACT

To explore the differences between fenestration technique and parallel grafts technique of thoracic endovascular aortic repair, and evaluate the risk of complications after interventional treatment of aortic arch aneurysms. A three-dimensional aortic model was established from the follow-up imaging data of patient who reconstructed the superior arch vessel by the chimney technique, which was called the chimney model. Based on the chimney model, the geometric of the reconstructed vessel was modified by virtual surgery, and the normal model, fenestration model and periscope model were established. The blood flow waveforms measured by 2D phase contrast magnetic resonance imaging were processed as the boundary conditions of the ascending aorta inlet and the superior arch vessels outlets of the normal model. The pressure waveform of descending aorta was obtained using three-element Windkessel model, and specific pressure boundary conditions were imposed at reconstructed branches for the postoperative models. Through computational fluid dynamics simulations, the hemodynamic parameters of each model were obtained. The reconstructed vessel flow rate of the periscope model and the fenestration model are 33% and 50% of that of the normal model, respectively. The pressure difference between the inner and outer walls of the fenestration stent and periscope stent is 3.15 times and 7.56 times that of the chimney stent. The velocity in the fenestration stent and periscope stent is uneven. The high relative residence time is concentrated in the region around the branch stents, which is prone to thrombosis. The "gutter" part of the chimney model may become larger due to the effect of the stent-graft DF, increasing the risk of endoleak. For patients with incomplete circle of Willis, the periscope technique to reconstruct the supra-arch vessels may affect blood perfusion. It is recommended to use balloon-expandable stent for fenestration stent and periscope stent, and self-expanding stent for chimney stent. For patients with aortic arch aneurysms, the fenestration technique may be superior to the parallel grafts technique.


Subject(s)
Aneurysm, Aortic Arch , Aortic Aneurysm, Thoracic , Blood Vessel Prosthesis Implantation , Endovascular Procedures , Humans , Blood Vessel Prosthesis , Blood Vessel Prosthesis Implantation/methods , Endovascular Aneurysm Repair , Aortic Aneurysm, Thoracic/surgery , Treatment Outcome , Risk Factors , Endovascular Procedures/methods , Aortography/methods , Time Factors , Stents , Aorta, Thoracic/surgery , Prosthesis Design
17.
Plant Physiol Biochem ; 201: 107813, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37290134

ABSTRACT

Zanthoxylum armatum is a dioecious prickly plant which developed apomictic reproduction. The increases in male flowers and prickle density in female plants lead to low yield and picking efficiency. However, little is known concerning the mechanisms of floral development and prickle formation. NAC is a well-known transcription factor that participates in multiple aspects of plant growth and development. Herein, we characterize the functions and regulatory mechanisms of candidate NACs controlling both traits in Z. armatum. A total of 159 ZaNACs were identified, and 16 of these were male-biased, represented by the NAP subfamily members ZaNAC93 and ZaNAC34, orthologs of AtNAC025 and AtNARS1/NAC2 respectively. Overexpression of ZaNAC93 in tomato led to modifications in flower and fruit development, including earlier flowering, increased numbers of lateral shoots and flowers, accelerated plant senescence, and reduced size and weight of fruits and seeds. In addition, the trichome density in leaves and inflorescences was dramatically reduced in ZaNAC93-OX lines. Overexpression of ZaNAC93 resulted in the up-/downregulation of genes associated with GA, ABA and JA signaling pathways, such as GAI, PYL and JAZ, as well as several TFs, including bZIP2, AGL11, FBP24 and MYB52. Yeast two-hybrid analysis revealed that ZaNAC93 protein could interact with AP1, GAI, bZIP2 and AGL11 in Z. armatum, which might contribute to floral induction, fruit growth, and trichome initiation. This work provides new insights into the molecular mechanisms of ZaNAC93 in reproductive development and prickle formation in Z. armatum.


Subject(s)
Fruit , Zanthoxylum , Fruit/genetics , Plant Extracts/pharmacology , Zanthoxylum/genetics , Transcription Factors/genetics , Reproduction
18.
Dalton Trans ; 52(27): 9448-9455, 2023 Jul 11.
Article in English | MEDLINE | ID: mdl-37366087

ABSTRACT

Molecular ferroelectric materials have been widely used in capacitors and sensors due to their low cost, light weight, flexibility and good biocompatibility. Organic-inorganic hybrid complexes, on the other hand, have received a great deal of attention in the luminescence field due to their low cost and simple preparation. The combination of ferroelectricity and photoluminescence in organic-inorganic hybrid materials not only leads to tunable optical properties, but also enriches potential applications of multifunctional ferroelectrics in optoelectronic devices. Here, we report a new luminescent ferroelectric material (1,3-dicyclohexylimidazole)2MnCl4 (DHIMC). Thermogravimetric analysis (TGA) was used to measure the mass change of the material at a measurement rate of 20 K min-1 from room temperature to 900 K, and we found that this material has good thermostability, which is up to 383 K. Meanwhile, UV-vis measurements showed that it is also a fluorescent material emitting a strong green fluorescence at the wavelength of 525 nm. The ferroelectricity of the crystal was determined by two different methods: the Sawyer-Tower method and the double-wave method (DWM). Particularly, the single crystal experiences a phase transition from the ferroelectric phase to the paraelectric phase during the heating/cooling process at 318 K/313 K and the space group changes from P1̄ (centrosymmetric) to P1 (non-centrosymmetric). This work will enrich multifunctional luminescent ferroelectric materials and their application in display and sensing.

19.
Gene ; 871: 147434, 2023 Jun 30.
Article in English | MEDLINE | ID: mdl-37068692

ABSTRACT

Zanthoxylum armatum is an evergreen plant with high economical and medicinal values. The presence of prickles on stems and leaves is undesirable for them make picking difficult. To date, little is known of prickle formation in Z. armatum. Herein, the morphological and molecular features of prickle initiation in prickless (WC) and three types of prickly Z. armatum were characterized. Compared to WC, the levels of cytokinin and auxin were increased, while GA and JA declined in prickly Z. armatum. Transcriptome analysis identified 6258 differentially expressed genes (DEGs) between prickless and prickly Z. armatum. Among them, several DEGs related to hormone metabolism and signaling, including LOG7, CKX3, AHK1, three DELLAs, six JAZs and TIR1, were candidate genes involved in prickle formation. Transcription factors associated with prickle formation were screened, including MYB6-1/MYB6-2, WER, GL3-2, SPL4/5, SOC1, and SCL32. Of them, MYB6-1 and WER might negatively regulate prickles initiation via interacting with GL3-2. Additionally, the histone acetylation and DNA methylation levels, the transcripts of histone acetyltransferase/deacetylase and DNA methyltransferases showed significant differences between prickless and prickly plants, indicating their involvements in prickle initiation. These findings illustrate the regulation of prickle formation might be mediated by phytohormones (especially cytokinin), transcription factors and epigenetic modifications in Z. armatum.


Subject(s)
Plant Extracts , Zanthoxylum , Zanthoxylum/genetics , Epigenesis, Genetic , Gene Expression Profiling , Hormones
20.
Article in English | MEDLINE | ID: mdl-37903334

ABSTRACT

The electrocaloric effect (ECE) is a novel technology that offers high efficiency and environmental friendliness, making it suitable for solid-state refrigeration applications. Among the extensively studied ECE materials, lead scandium tantalate (PST) stands out for its excellent performance. However, its applications are restricted by its narrow working temperature range. To overcome this limitation, we explore the enhancement of the ECE through zirconium ion doping. We synthesized PbSc0.5-0.5xTa0.5-0.5xZrxO3 samples (x = 0, 0.025, 0.05, 0.075). The introduction of zirconium ions led to an increase in the Curie temperature from 28.9 °C (x = 0) to 55.5 °C (x = 0.075). Additionally, the relaxation factor γ of the ceramics increased from 1.40 (x = 0) to 1.59 (x = 0.075). The temperature span (Tspan) exhibited a rising trend with increasing x, reaching 10.9 K at x = 0.075. The maximum temperature change (ΔTmax) was observed at x = 0.025, with a value of 1.94 K. X-ray diffraction (XRD) patterns revealed that zirconium ion doping influenced the B-site ordering degree, thereby regulating the ECE. To further validate the results, we employed direct measurements and thermodynamic calculations. Overall, the regulation of ionic ordering through zirconium doping effectively enhances the ECE performance. These findings contribute to the development of advanced materials for solid-state refrigeration technologies.

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