Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 60
Filter
Add more filters

Country/Region as subject
Affiliation country
Publication year range
1.
J Cell Mol Med ; 28(12): e18451, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38898783

ABSTRACT

Exosomes derived from bone marrow-derived mesenchymal stem cells (BMSCs) can alleviate the symptoms of pelvic floor dysfunction (PFD) in rats. However, the potential therapeutical effects of exosomes derived from BMSCs treated with tumour necrosis factor (TNF)-α on the symptoms of PFD in rats are unknown. Exosomes extracted from BMSCs treated with or without TNF-α were applied to treat PFD rats. Our findings revealed a significant elevation in interleukin (IL)-6 and TNF-α, and matrix metalloproteinase-2 (MMP2) levels in the vaginal wall tissues of patients with pelvic organ prolapse (POP) compared with the control group. Daily administration of exosomes derived from BMSCs, treated either with or without TNF-α (referred to as Exo and TNF-Exo), resulted in increased void volume and bladder void pressure, along with reduced peak bladder pressure and leak point pressure in PFD rats. Notably, TNF-Exo treatment demonstrated superior efficacy in restoring void volume, bladder void pressure and the mentioned parameters compared with Exo treatment. Importantly, TNF-Exo exhibited greater potency than Exo in restoring the levels of multiple proteins (Elastin, Collagen I, Collagen III, IL-6, TNF-α and MMP2) in the anterior vaginal walls of PFD rats. The application of exosomes derived from TNF-α-treated BMSCs holds promise as a novel therapeutic approach for treating PFD.


Subject(s)
Exosomes , Matrix Metalloproteinase 2 , Mesenchymal Stem Cells , Pelvic Organ Prolapse , Tumor Necrosis Factor-alpha , Animals , Exosomes/metabolism , Exosomes/transplantation , Mesenchymal Stem Cells/metabolism , Female , Tumor Necrosis Factor-alpha/metabolism , Rats , Humans , Pelvic Organ Prolapse/therapy , Pelvic Organ Prolapse/metabolism , Matrix Metalloproteinase 2/metabolism , Rats, Sprague-Dawley , Interleukin-6/metabolism , Pelvic Floor , Disease Models, Animal , Bone Marrow Cells/metabolism , Vagina/pathology , Mesenchymal Stem Cell Transplantation/methods , Pelvic Floor Disorders/therapy , Middle Aged
2.
Opt Express ; 32(5): 7044-7052, 2024 Feb 26.
Article in English | MEDLINE | ID: mdl-38439395

ABSTRACT

The carrier transport performances play key roles in the photoelectric conversion efficiency for photovoltaic effect. Hence, the low carrier mobility and high photogenerated carrier recombination in ferroelectric materials depress the separation of carriers. This work designs a ferroelectric polarization-interface-free PN junction composed with P-type semiconductor BiFeO3 (BFO) derived from the variable valence of Fe and N-type semiconductor BiFe0.98Ti0.02O3 (BFTO) through Ti donor doping. The integration of the ferroelectricity decides the PN junction without polarization coupling like the traditional heterojunctions but only existing carrier distribution differential at the interface. The carrier recombination in PN junction is significantly reduced due to the driving force of the built-in electric field and the existence of depletion layer, thereby enhancing the switching current 3 times higher than that of the single ferroelectric films. Meanwhile, the carrier separation at the interface is significantly engineered by the polarization, with open circuit voltage and short circuit current of photovoltaic effect increased obviously. This work provides an alternative strategy to regulate bulk ferroelectric photovoltaic effects by carrier transport engineering in the polarization-interface-free ferroelectric PN junction.

3.
BMC Cardiovasc Disord ; 24(1): 312, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38902636

ABSTRACT

BACKGROUND: Previous studies have shown the importance of energy deficiency and malfunctioning mitochondria in the pathophysiology of hypertrophic cardiomyopathy (HCM). There has been a little research into the relationship between plasma free fatty acids (FFA), one of the heart's main energy sources, and HCM. We evaluated its clinical importance in HCM to see if there was a link between plasma FFA metabolism and HCM. METHODS: In a single-center retrospective observational study, we investigated 420 HCM patients diagnosed at Beijing Anzhen Hospital between January 1, 2018, and December 31, 2022. Meanwhile, 1372 individuals without HCM (non-HCM) were recruited. 391 non-HCM patients were chosen as controls via a propensity score matching (PSM) study with a 1:1 ratio. RESULTS: FFA in HCM patients showed statistically significant correlations with creatinine (r = 0.115, p = 0.023), estimated GFR (r=-0.130, p = 0.010), BNP (r = 0.152, p = 0.007), LVEF (r=-0.227, p < 0.001), LVFS (r=-0.160, p = 0.002), and LAD (r = 0.112, p = 0.028). Higher FFA levels were found in HCM patients who had atrial fibrillation and NYHY functional classes III or IV (p = 0.015 and p = 0.022, respectively). In HCM patients, multiple linear regression analysis revealed that BNP and LVEF had independent relationships with increasing FFA (Standardized = 0.139, p = 0.013 and =-0.196, p < 0.001, respectively). CONCLUSIONS: Among HCM patients, the plasma FFA concentration was lower, and those with AF and NYHY functional class III or IV had higher FFA levels, and LVEF and BNP were independently associated with increasing FFA. The findings of the study should help inspire future efforts to better understand how energy deficiency contributes to hypertrophic cardiomyopathy (HCM) development.


Subject(s)
Biomarkers , Cardiomyopathy, Hypertrophic , Fatty Acids, Nonesterified , Humans , Cardiomyopathy, Hypertrophic/physiopathology , Cardiomyopathy, Hypertrophic/blood , Cardiomyopathy, Hypertrophic/diagnosis , Retrospective Studies , Male , Female , Fatty Acids, Nonesterified/blood , Middle Aged , Biomarkers/blood , Adult , Energy Metabolism , Aged , Ventricular Function, Left , Beijing/epidemiology
4.
Opt Express ; 31(15): 24273-24282, 2023 Jul 17.
Article in English | MEDLINE | ID: mdl-37475258

ABSTRACT

The bandgap and polarization field play a key role in the ferroelectric photovoltaic effect. However, narrow bandgap induced electrical conductivity always brings out a depression of the photovoltaic performances. Based on the mechanisms of the photovoltaic effect and resistance switching behaviors in ferroelectric materials, this work realizes an evolution between the two effects by engineering the polarization field and barrier characteristics, which addresses the trade-off issues between the bandgap and polarization for ferroelectric photovoltaic effect. SrCoOx (SC, 2.5≤x≤3) with multivalent transition is introduced into Na0.5Bi0.5TiO3 (NBT) matrix material to engineered the polarization field and barrier characteristics. (1-x)NBT-xSC (x=0.03, 0.05, 0.07) solid solution films present an evolution of ferroelectric photovoltaic effect to grow out of nothing again to the disappearance of the photovoltaic effect and the appearance of resistance switching behavior. The 0.95NBT-0.05SC film achieve the open-circuit voltage of 0.81 V and the short-circuit current of 23.52 µA/cm2, and the 0.93NBT-0.07SC film obtains the resistive switching behavior with switch ratio of 100. This work provides a practicable strategy to achieve the fascinating evolution between photovoltaic effect and resistive switching.

5.
Opt Lett ; 48(7): 1582-1585, 2023 Apr 01.
Article in English | MEDLINE | ID: mdl-37221715

ABSTRACT

An unfavorable inverse relationship between polarization, bandgap, and leakage always limits the ferroelectric photovoltaic performances. This work proposes a strategy of lattice strain engineering different from traditional lattice distortion by introducing a (Mg2/3Nb1/3)3+ ion group into the B site of BiFeO3 films to construct local metal-ion dipoles. A giant remanent polarization of 98 µC/cm2, narrower bandgap of 2.56 eV, and the decreased leakage current by nearly two orders of magnitude are synchronously obtained in the BiFe0.94(Mg2/3Nb1/3)0.06O3 film by engineering the lattice strain, breaking through the inverse relationship among these three. Thereby, the open-circuit voltage and the short-circuit current of the photovoltaic effect reach as high as 1.05 V and 2.17 µA /cm2, respectively, showing an excellent photovoltaic response. This work provides an alternative strategy to enhance ferroelectric photovoltaic performances by lattice strain derived from local metal-ion dipoles.

6.
Eur Radiol ; 33(4): 2312-2323, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36378251

ABSTRACT

OBJECTIVES: This study investigated the discriminability of quantitative radiomics features extracted from cardiac magnetic resonance (CMR) images for hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM), and healthy (NOR) patients. METHODS: The data of two hundred and eighty-three patients with HCM (n = 48) or DCM (n = 52) and NOR (n = 123) were extracted from two publicly available datasets. Ten feature selection methods were first performed on twenty-one different sets of radiomics features extracted from the left ventricle, right ventricle, and myocardium segmented from CMR images in the end-diastolic frame, end-systolic frame, and a combination of both; then, nine classical machine learning methods were trained with the selected radiomics features to distinguish HCM, DCM, and NOR. Ninety classification models were constructed based on combinations of the ten feature selection methods and nine classifiers. The classification models were evaluated, and the optimal model was selected. The diagnostic performance of the selected model was also compared to that of state-of-the-art methods. RESULTS: The random forest minimum redundancy maximum relevance model with features based on LeastAxisLength, Maximum2DDiameterSlice, Median, MinorAxisLength, Sphericity, VoxelVolume, Kurtosis, Flatness, and Skewness was the highest performing model, achieving 91.2% classification accuracy. The cross-validated areas under the curve on the test dataset were 0.938, 0.966, and 0.936 for NOR, DCM, and HCM, respectively. Furthermore, compared with those of the state-of-the-art methods, the sensitivity and accuracy of this model were greatly improved. CONCLUSIONS: A predictive model was proposed based on CMR radiomics features for classifying HCM, DCM, and NOR patients. The model had good discriminability. KEY POINTS: • The first-order features and the features extracted from the LOG-filtered images have potential in distinguishing HCM patients from DCM patients. • The features extracted from the RV play little role in distinguishing DCM from HCM. • The VoxelVolume of the myocardium in the ED frame is important in the recognition of DCM.


Subject(s)
Cardiomyopathy, Dilated , Cardiomyopathy, Hypertrophic , Humans , Heart , Magnetic Resonance Imaging , Myocardium/pathology , Cardiomyopathy, Hypertrophic/diagnostic imaging , Cardiomyopathy, Dilated/pathology , Magnetic Resonance Spectroscopy
7.
Phys Chem Chem Phys ; 25(47): 32372-32377, 2023 Dec 06.
Article in English | MEDLINE | ID: mdl-37990823

ABSTRACT

A narrow-bandgap-induced potential field always results in decreased photovoltaic performance. Here, a finite solid solution was designed to explore the simultaneous improvement of the polarization property and bandgap obtained from the critical effect in which BiMnO3 (BM) enters the Na0.5Bi0.5TiO3 (NBT) crystal lattice, resulting in a strong lattice expansion; by contrast, the incorporation of Mn without a d-orbital weakened the orbital hybridization accompanied by Jahn-Teller (J-T) distortion to reduce the optical bandgap. A narrow bandgap of 2.90 eV and polarization of 65.9 µC cm-2 were achieved by finite solid solution engineering. The open-circuit voltage and the short-circuit current with a BM doping component of 0.04 reached as high as 1.1 V and 0.0132 mA cm-2, respectively. This work provides an optimized strategy for the mutual benefit of the polarization and bandgap by finite solid solution engineering.

8.
Bioorg Chem ; 119: 105483, 2022 02.
Article in English | MEDLINE | ID: mdl-34906860

ABSTRACT

The nuclear receptor retinoic acid receptor-related orphan receptor γ (RORγ, NR1F3, or RORc) exists in two isoforms, with one isoform (RORγ or RORc1) widely expressed in a variety of tissues, and the expression of the second isoform (RORγt or RORc2) restricted to the thymus and cells of the immune system. RORγt is a key regulator of the development and functions of T-helper 17 (Th17) cells. Clinical proof-of-concept (PoC) with small molecule inverse agonists of RORγt has been achieved with VTP-43742 (Phase II) for the treatment of psoriasis, and pre-clinical PoC for this mechanism has also been established for the treatment of autoimmune diseases. A series of aryl sulfonyl derivatives as novel RORγt inverse agonists were designed and synthesized based on VTP-43742. We conducted structural modifications that improved the activity profile. In pharmacodynamic (PD) studies, oral administration of compound b12 showed robust and dose-dependent inhibition of IL-6 and IL-17A cytokine expression. The ability of compound b12 to reduce the levels of IL-6 and IL-17A in vivo after oral dosing in mice, and a corresponding reduction in skin inflammation further supports the potential of small molecule RORγt modulation as a therapeutic target for the treatment of inflammatory diseases.


Subject(s)
Drug Discovery , Nuclear Receptor Subfamily 1, Group F, Member 3/agonists , Administration, Oral , Animals , Dose-Response Relationship, Drug , Female , Humans , Mice , Mice, Inbred BALB C , Molecular Structure , Structure-Activity Relationship
9.
BMC Med Imaging ; 22(1): 130, 2022 07 23.
Article in English | MEDLINE | ID: mdl-35870877

ABSTRACT

BACKGROUND: Cervical cancer cell detection is an essential means of cervical cancer screening. However, for thin-prep cytology test (TCT)-based images, the detection accuracies of traditional computer-aided detection algorithms are typically low due to the overlapping of cells with blurred cytoplasmic boundaries. Some typical deep learning-based detection methods, e.g., ResNets and Inception-V3, are not always efficient for cervical images due to the differences between cervical cancer cell images and natural images. As a result, these traditional networks are difficult to directly apply to the clinical practice of cervical cancer screening. METHOD: We propose a cervical cancer cell detection network (3cDe-Net) based on an improved backbone network and multiscale feature fusion; the proposed network consists of the backbone network and a detection head. In the backbone network, a dilated convolution and a group convolution are introduced to improve the resolution and expression ability of the model. In the detection head, multiscale features are obtained based on a feature pyramid fusion network to ensure the accurate capture of small cells; then, based on the Faster region-based convolutional neural network (R-CNN), adaptive cervical cancer cell anchors are generated via unsupervised clustering. Furthermore, a new balanced L1-based loss function is defined, which reduces the unbalanced sample contribution loss. RESULT: Baselines including ResNet-50, ResNet-101, Inception-v3, ResNet-152 and the feature concatenation network are used on two different datasets (the Data-T and Herlev datasets), and the final quantitative results show the effectiveness of the proposed dilated convolution ResNet (DC-ResNet) backbone network. Furthermore, experiments conducted on both datasets show that the proposed 3cDe-Net, based on the optimal anchors, the defined new loss function, and DC-ResNet, outperforms existing methods and achieves a mean average precision (mAP) of 50.4%. By performing a horizontal comparison of the cells on an image, the category and location information of cancer cells can be obtained concurrently. CONCLUSION: The proposed 3cDe-Net can detect cancer cells and their locations on multicell pictures. The model directly processes and analyses samples at the picture level rather than at the cellular level, which is more efficient. In clinical settings, the mechanical workloads of doctors can be reduced, and their focus can be placed on higher-level review work.


Subject(s)
Uterine Cervical Neoplasms , Female , Humans , Algorithms , Early Detection of Cancer/methods , Image Processing, Computer-Assisted/methods , Neural Networks, Computer , Uterine Cervical Neoplasms/diagnostic imaging
10.
Planta ; 254(6): 130, 2021 Nov 24.
Article in English | MEDLINE | ID: mdl-34817644

ABSTRACT

MAIN CONCLUSION: A Populus euphratica NAC gene regulates (1,3; 1,4)-ß-D-glucan content in oat developing seed and improves the spikelet number and grain number per spike in transgenic oat under salinity conditions Salinity is the major factor affecting the production and quality of oat, and improving oat salt tolerance to increase yield and quality is vital. (1,3;1,4)-ß-D-glucan in Gramineae is the key component in response to various environmental signals, and it is the most important functional ingredient in oat grain. The NAC transcription factors are important candidate genes used in genetic engineering to improve plant abiotic stress tolerance. In this study, we introduced Populus euphratica PeNAC1, controlled by its own promoter, into hexaploid cultivated oat and produced six transgenic lines. Compared to the non-transgenic control, the expression of PeNAC1 significantly improved the seed germination rate, seedling survival rate, and leaf chlorophyll content in the transgenic plants under salt stress. These physiological changes increased the spikelet number and grain number per spike in the transgenic oat under salinity conditions and reduced the yield loss per plant. The results indicated that the heterologous expression of PeNAC1 plays an effective role in improving the salt tolerance in transgenic oat. In addition, overexpressing PeNAC1 significantly increased the (1,3;1,4)-ß-D-glucan content as well as the expression level of the (1,3;1,4)-ß-D-glucan biosynthetic genes AsCslF3, AsCslF6, and AsCslF9 in the transgenic lines under salt stress, which suggested that PeNAC1 regulates the synthesis of (1,3;1,4)-ß-D-glucan. Our research should assist in the discovery of the diverse action modes of NAC proteins, while PeNAC1 will be useful for improving the salt tolerance and quality of oat through molecular breeding.


Subject(s)
Salt Tolerance , Transcription Factors , Avena/genetics , Avena/metabolism , Gene Expression Regulation, Plant , Glucans , Plant Proteins/genetics , Plant Proteins/metabolism , Plants, Genetically Modified/metabolism , Salinity , Salt Tolerance/genetics , Stress, Physiological/genetics , Transcription Factors/genetics , Transcription Factors/metabolism
11.
Mar Drugs ; 18(11)2020 Nov 06.
Article in English | MEDLINE | ID: mdl-33172133

ABSTRACT

Four new purified polysaccharides (PAP) were isolated and purified from the Enteromorpha prolifera by alkali extraction, and further characterization was investigated. Their average molecular weights of PAP-1, PAP-2, PAP-3, and PAP-4 were estimated as 3.44 × 104, 6.42 × 104, 1.20 × 105, and 4.82 × 104 Da, respectively. The results from monosaccharide analysis indicated that PAP-1, PAP-2, PAP-3 were acidic polysaccharides and PAP-4 was a neutral polysaccharide. PAP-1 and PAP-2 mainly consist of galacturonic acid, while PAP-3 and PAP-4 mainly contained rhamnose. Congo red test showed that no triple helical structure was detected in the four polysaccharides. The antioxidant activities were investigated using 1,1-diphenyl-2-picrylhydrazyl (DPPH), Superoxide, and 2, 2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical assay. In vitro antitumor activities were evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. PAP-1 exhibited relatively stronger antioxidant activities among the four polysaccharides in a dose-dependent manner. At a concentration of 1.00 mg/mL, the antioxidant activities of PAP-1 on the DPPH radical scavenging rate, superoxide anion radical scavenging rate, and ABTS radical rate at 1.00 mg/mL were 56.40%, 54.27%, and 42.07%, respectively. They also showed no significant inhibitory activity against MGC-803, HepG2, T24, and Bel-7402 cells. These investigations of polysaccharides provide a scientific basis for the use of E. prolifera as an ingredient in functional foods and medicines.


Subject(s)
Antioxidants/pharmacology , Chlorophyta/metabolism , Polysaccharides/pharmacology , Alkalies/chemistry , Animals , Antineoplastic Agents/isolation & purification , Antineoplastic Agents/pharmacology , Antioxidants/isolation & purification , Chemical Fractionation , Erythrocytes/drug effects , Erythrocytes/metabolism , Erythrocytes/pathology , Hemolysis/drug effects , Hep G2 Cells , Humans , Hydrogen Peroxide/toxicity , Mice, Inbred ICR , Molecular Structure , Polysaccharides/isolation & purification , Structure-Activity Relationship
12.
J Cell Biochem ; 119(2): 2258-2268, 2018 02.
Article in English | MEDLINE | ID: mdl-28857294

ABSTRACT

Angiogenesis of liver sinusoidal endothelial cells (LSECs) accompanies with hypoxia in liver fibrosis and they are of mutual promotion, which has raised wide concern. Here we established murine model of liver fibrosis and found that oroxylin A (40 mg/kg) could ameliorate angiogenesis in liver fibrosis may related to hypoxia inducible factor 1α (HIF-1α). The underlying mechanism was further investigated by isolating and culturing murine primary LSECs. Hypoxia induced vascular endothelial growth factor A (VEGF-A), angiopoietin 2 (Ang-2), and platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31) elevated in LSECs were reduced by oroxylin A or acriflavine (ACF, an HIF-1α inhibitor), indicating HIF-1α involved the angiogenesis of LSECs. Additionally, interference with Yes-associated protein (YAP) significant downregulated the protein expression of HIF-1α and VEGF-A, while YAP plasmid exhibited an opposite effect. We next found that oroxylin A inhibited hypoxia-induced nuclear translocation of YAP, which may influence the accumulation of HIF-1α and subsequently decrease transcription of downstream target gene including VEGF-A and Ang-2, thereby exerting an anti-angiogenic activity.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Flavonoids/administration & dosage , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Liver Cirrhosis/drug therapy , Neovascularization, Pathologic/prevention & control , Phosphoproteins/metabolism , Angiopoietin-2/genetics , Angiopoietin-2/metabolism , Animals , Carbon Tetrachloride/toxicity , Cell Cycle Proteins , Cells, Cultured , Disease Models, Animal , Endothelial Cells/cytology , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Flavonoids/pharmacology , Gene Expression Regulation/drug effects , Liver Cirrhosis/chemically induced , Liver Cirrhosis/genetics , Liver Cirrhosis/metabolism , Male , Mice , Neovascularization, Pathologic/metabolism , Signal Transduction/drug effects , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/metabolism , YAP-Signaling Proteins
13.
Am J Physiol Renal Physiol ; 315(4): F1042-F1057, 2018 10 01.
Article in English | MEDLINE | ID: mdl-29923765

ABSTRACT

Renal iron recycling preserves filtered iron from urinary excretion. However, it remains debated whether ferroportin (FPN), the only known iron exporter, is functionally involved in renal iron recycling and whether renal iron recycling is required for systemic iron homeostasis. We deleted FPN in whole nephrons by use of a Nestin-Cre and in the distal nephrons and collecting ducts, using a Ksp-Cre, and investigated its impacts on renal iron recycling and systemic iron homeostasis. FPN deletion by Nestin-Cre, but not by Ksp-Cre, caused excess iron retention and increased ferritin heavy chain (FTH1) specifically in the proximal tubules and resulted in the reduction of serum and hepatic iron. The systemic iron redistribution was aggravated, resulting in anemia and the marked downregulation of hepatic hepcidin in elderly FPN knockout (KO)/Nestin-Cre mice. Similarly, in iron-deficient FPN KO/Nestin-Cre mice, the renal iron retention worsened anemia with the activation of the erythropoietin-erythroferrone-hepcidin pathway and the downregulation of hepatic hepcidin. Hence, FPN likely located at the basolateral membrane of the proximal tubules to export iron into the circulation and was required for renal iron recycling and systemic iron homeostasis particularly in elderly and iron-deficient mice. Moreover, FPN deletion in the proximal tubules alleviated ischemic acute kidney injury, possibly by upregulating FTH1 to limit catalytic iron and by priming antioxidant mechanisms, indicating that FPN could be deleterious in the pathophysiology of ischemic acute kidney injury (AKI) and thus may be a potential target for the prevention and mitigation of ischemic AKI.


Subject(s)
Acute Kidney Injury/metabolism , Cation Transport Proteins/metabolism , Iron/metabolism , Ischemia/metabolism , Animals , Hepcidins/metabolism , Homeostasis/physiology , Kidney/metabolism , Kidney Tubules, Proximal/metabolism , Liver/metabolism , Mice, Transgenic , Spleen/metabolism
14.
IUBMB Life ; 69(2): 115-127, 2017 02.
Article in English | MEDLINE | ID: mdl-28112475

ABSTRACT

Accumulating evidence indicates that hedgehog signaling plays a pivotal role in pathological angiogenesis and is involved in wound-healing responses in a number of adult tissues, including the liver. We previously demonstrated that hedgehog signaling promoted proliferation and inhibited apoptosis in hepatic stellate cells. This study was aimed to evaluate the effect of tetramethylpyrazine (TMP) on hedgehog signaling and to further examine the molecular mechanisms of TMP-induced antiangiogenesic effects in liver fibrosis. We found that TMP ameliorated the expression of proangiogenic markers vascular endothelial growth factor A (VEGF-A), vascular endothelial growth factor receptor 2 (VEGF-R2), platelet-derived growth factor BB (PDGF-BB), platelet-derived growth factor-ß receptor (PDGF-ßR) and hypoxia inducible factor 1α (HIF-1α), concomitant with reduced abundance of endothelial markers platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31), CD34 and von willebrand factor in vivo and in vitro. Interestingly, TMP attenuated the abundance of sonic hedgehog, smoothened (Smo) and glioblastoma but increased the expression of hedgehog-interacting protein in liver sinusoidal endothelial cells, which was underlying mechanism for the antiangiogenesic activity of TMP. Downregulation of Smo activity, using selective Smo inhibitor cyclopamine, lead to a synergistic effect with TMP, whereas Smo overexpression plasmid impaired the induction of antiangiogenesic effects of TMP. Overall, these results provide novel implications to reveal the molecular mechanism of TMP-inhibited liver sinusoidal angiogenesis, by which points to the possibility of using TMP-based antiangiogenic drugs for the treatment of liver fibrosis. © 2017 IUBMB Life, 69(2):115-127, 2017.


Subject(s)
Hedgehog Proteins/genetics , Liver Cirrhosis/drug therapy , Neovascularization, Pathologic/drug therapy , Pyrazines/administration & dosage , Smoothened Receptor/genetics , Animals , Carbon Tetrachloride/toxicity , Cell Proliferation/drug effects , Gene Expression Regulation , Hedgehog Proteins/antagonists & inhibitors , Hedgehog Proteins/biosynthesis , Humans , Liver Cirrhosis/chemically induced , Liver Cirrhosis/genetics , Liver Cirrhosis/pathology , Mice , Neovascularization, Pathologic/chemically induced , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/pathology , Nitric Oxide/genetics , Nitric Oxide Synthase/genetics , Primary Cell Culture , Smoothened Receptor/antagonists & inhibitors , Smoothened Receptor/biosynthesis
15.
Reprod Biomed Online ; 34(5): 473-479, 2017 May.
Article in English | MEDLINE | ID: mdl-28236600

ABSTRACT

Single-embryo image assessment involves a high degree of inaccuracy because of the imprecise labelling of the transferred embryo images. In this study, we considered the entire transfer cycle to predict the implantation potential of embryos, and propose a novel algorithm based on a combination of local binary pattern texture feature and Adaboost classifiers to predict pregnancy rate. The first step of the proposed method was to extract the features of the embryo images using the local binary pattern operator. After this, multiple embryo images in a transfer cycle were considered as one entity, and the pregnancy rate was predicted using three classifiers: the Real Adaboost, Gentle Adaboost, and Modest Adaboost. Finally, the pregnancy rate was determined via the majority vote rule based on classification results of the three Adaboost classifiers. The proposed algorithm was verified to have a good predictive performance and may assist the embryologist and clinician to select embryos to transfer and in turn improve pregnancy rate.


Subject(s)
Algorithms , Embryo Transfer , Pregnancy Rate , Adult , Female , Humans , Pregnancy
16.
Nanotechnology ; 28(45): 455705, 2017 Nov 10.
Article in English | MEDLINE | ID: mdl-28901953

ABSTRACT

Cluster-assembled SmCo alloy films were prepared by low energy cluster beam deposition. The structure, magnetic domain, magnetization, and magnetostriction of the films were characterized. It is shown that the as-prepared films are assembled in compact and uniformly distributed spherical cluster nanoparticles, most of which, after vacuum in situ annealing at 700 K, aggregated to form cluster islands. These cluster islands result in transformations from superparamagnetic states to magnetic single domain (MSD) states in the films. Such MSD structures contribute to the enhanced magnetostrictive behaviors with a saturation magnetostrictive coefficient of 160 × 10-6 in comparison to 105 × 10-6 for the as-prepared films. This work demonstrates candidate materials that could be applied in nano-electro-mechanical systems, low power information storage, and weak magnetic detecting devices.

18.
Nat Commun ; 15(1): 5549, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38956065

ABSTRACT

Hybrid improper ferroelectricity can effectively avoid the intrinsic chemical incompatibility of electronic mechanism for multiferroics. Perovskite superlattices, as theoretically proposed hybrid improper ferroelectrics with simple structure and high technological compatibility, are conducive to device integration and miniaturization, but the experimental realization remains elusive. Here, we report a strain-driven oxygen octahedral distortion strategy for hybrid improper ferroelectricity in La2NiMnO6/La2CoMnO6 double-perovskite superlattices. The epitaxial growth mode with mixed crystalline orientations maintains a large strain transfer distance more than 90 nm in the superlattice films with lattice mismatch less than 1%. Such epitaxial strain permits sustainable long-range modulation of oxygen octahedral rotation and tilting, thereby inducing and regulating hybrid improper ferroelectricity. A robust room-temperature ferroelectricity with remnant polarization of ~ 0.16 µC cm-2 and piezoelectric coefficient of 2.0 pm V-1 is obtained, and the density functional theory calculations and Landau-Ginsburg-Devonshire theory reveal the constitutive correlations between ferroelectricity, octahedral distortions, and strain. This work addresses the gap in experimental studies of hybrid improper ferroelectricity for perovskite superlattices and provides a promising research platform and idea for designing and exploring hybrid improper ferroelectricity.

19.
Adv Mater ; : e2411467, 2024 Oct 10.
Article in English | MEDLINE | ID: mdl-39385657

ABSTRACT

Nanoscale polar regions, or nanodomains (NDs), are crucial for understanding the domain structure and high susceptibility of relaxors. However, unveiling the evolution and function of NDs during polarization switching at the microscopic level is of great challenge. The experimental in situ characterization of NDs under electric-field perturbations, and computational accurate prediction of the dipole switching within a sufficiently large supercell, are notoriously tricky and tedious. These difficulties hinder a full understanding of the link between micro domain dynamics and macro polarization switching. Herein, the real-time evolution of NDs at the nanoscale is observed and visualized during polarization switching in an exemplary relaxor system of Bi5- xLaxMg0.5Ti3.5O15. Two fundamentally different domain switching pathways and dynamic characteristics are revealed: one steep, bipolar-like switching between two degenerate polarization states; and another flat, multi-step switching process with a thermodynamically stable non-polar mesophase mediating the degenerate polarization states. The two are determined by the distinct Landau energy landscapes that are strongly dependent on the intrinsic domain configurations and interdomain interactions. This work bridges the gap between micro domain dynamics and macro polarization switching, providing a guiding principle for the strategic design and optimization of relaxors.

20.
Comput Biol Med ; 164: 107290, 2023 09.
Article in English | MEDLINE | ID: mdl-37579584

ABSTRACT

The UNet series networks have been a leader in the field of medical image segmentation since their introduction. However, encoder and decoder structures of the traditional UNet series network are complex, with a large number of parameters and floating-point operations. This requires a large amount of data as support for model training, but most medical datasets only contain limited numbers of samples. To address this issue, we propose a global frequency domain UNet (GFUNet), a novel architecture for fast medical image segmentation. Inspired by recent modified Multi-Layer Perceptron(MLP)-like models, we combine Fourier Transform with UNet structure to achieve more efficient and effective encoding and decoding processes. Meanwhile, A dual-domain encoding module is designed to improve the performance of the encoder and decoder by fully used frequency domain feature. Furthermore, due to the excellent property of the Fourier Transform and its optimization, our network greatly reduces the number of parameters compared to other UNets. We evaluate GFUNet on several medical segmentation tasks, achieving improved segmentation performance compared to state-of-the-art network architectures for medical image segmentation. Compared to the original UNet, the results show that we reduce the number of parameters by 46 times, reduce computational complexity by 114 times, and improved the considerable dice score.


Subject(s)
Image Processing, Computer-Assisted , Neural Networks, Computer
SELECTION OF CITATIONS
SEARCH DETAIL