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1.
Plant Physiol ; 195(3): 2309-2322, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38466216

RESUMO

Soil (or plant) water deficit accelerates plant reproduction. However, the underpinning molecular mechanisms remain unknown. By modulating cell division/number, ABSCISIC ACID-INSENSITIVE 5 (ABI5), a key bZIP (basic (region) leucine zippers) transcription factor, regulates both seed development and abiotic stress responses. The KIP-RELATED PROTEIN (KRP) cyclin-dependent kinases (CDKs) play an essential role in controlling cell division, and SHOOT MERISTEMLESS (STM) plays a key role in the specification of flower meristem identity. Here, our findings show that abscisic acid (ABA) signaling and/or metabolism in adjust reproductive outputs (such as rosette leaf number and open flower number) under water-deficient conditions in Arabidopsis (Arabidopsis thaliana) plants. Reproductive outputs increased under water-sufficient conditions but decreased under water-deficient conditions in the ABA signaling/metabolism mutants abscisic acid2-1 (aba2-1), aba2-11, abscisic acid insensitive3-1 (abi3-1), abi4-1, abi5-7, and abi5-8. Further, under water-deficient conditions, ABA induced-ABI5 directly bound to the promoter of KRP1, which encodes a CDK that plays an essential role in controlling cell division, and this binding subsequently activated KRP1 expression. In turn, KRP1 physically interacted with STM, which functions in the specification of flower meristem identity, promoting STM degradation. We further demonstrate that reproductive outputs are adjusted by the ABI5-KRP1-STM molecular module under water-deficient conditions. Together, our findings reveal the molecular mechanism by which ABA signaling and/or metabolism regulate reproductive development under water-deficient conditions. These findings provide insights that may help guide crop yield improvement under water deficiency.


Assuntos
Ácido Abscísico , Proteínas de Arabidopsis , Arabidopsis , Flores , Regulação da Expressão Gênica de Plantas , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Ácido Abscísico/metabolismo , Flores/genética , Flores/crescimento & desenvolvimento , Flores/fisiologia , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Transdução de Sinais , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Reprodução , Mutação/genética , Quinases Ciclina-Dependentes/metabolismo , Quinases Ciclina-Dependentes/genética , Proteínas de Homeodomínio
2.
FASEB J ; 38(2): e23409, 2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38193628

RESUMO

Diabetic kidney disease (DKD) is one of the severe complications of diabetes mellitus, yet there is no effective treatment. Exploring the development of DKD is essential to treatment. Podocyte injury and inflammation are closely related to the development of DKD. However, the mechanism of podocyte injury and progression in DKD remains largely unclear. Here, we observed that FTO expression was significantly upregulated in high glucose-induced podocytes and that overexpression of FTO promoted podocyte injury and inflammation. By performing RNA-seq and MeRIP-seq with control podocytes and high glucose-induced podocytes with or without FTO knockdown, we revealed that serum amyloid A2 (SAA2) is a target of FTO-mediated m6A modification. Knockdown of FTO markedly increased SAA2 mRNA m6A modification and decreased SAA2 mRNA expression. Mechanistically, we demonstrated that SAA2 might participate in podocyte injury and inflammation through activation of the NF-κB signaling pathway. Furthermore, by generating podocyte-specific adeno-associated virus 9 (AAV9) to knockdown SAA2 in mice, we discovered that the depletion of SAA2 significantly restored podocyte injury and inflammation. Together, our results suggested that upregulation of SAA2 promoted podocyte injury through m6A-dependent regulation, thus suggesting that SAA2 may be a therapeutic target for diabetic kidney disease.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato , Nefropatias Diabéticas , Podócitos , Proteína Amiloide A Sérica , Animais , Camundongos , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Nefropatias Diabéticas/genética , Glucose , Inflamação/genética , NF-kappa B , RNA Mensageiro/genética , Transdução de Sinais , Proteína Amiloide A Sérica/genética
3.
Exp Cell Res ; 441(2): 114172, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39053869

RESUMO

In recent years, the impact of age-related diseases on human health has become increasingly severe, and developing effective drugs to deal with these diseases has become an urgent task. Considering the essential regulatory role of hydrogen sulfide (H2S) in these diseases, it is regarded as a promising target for treatment. H2S is a novel gaseous transmitter involved in many critical physiological activities, including anti-oxidation, anti-inflammation, and angiogenesis. H2S also regulates cell activities such as cell proliferation, migration, invasion, apoptosis, and autophagy. These regulatory effects of H2S contribute to relieving and treating age-related diseases. In this review, we mainly focus on the pathogenesis and treatment prospects of H2S in regulating age-related diseases.


Assuntos
Envelhecimento , Sulfeto de Hidrogênio , Sulfeto de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/farmacologia , Humanos , Envelhecimento/metabolismo , Animais , Autofagia/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos
4.
Anal Chem ; 96(19): 7411-7420, 2024 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-38652893

RESUMO

Accurate analysis of microRNAs (miRNAs) at the single-cell level is extremely important for deeply understanding their multiple and intricate biological functions. Despite some advancements in analyzing single-cell miRNAs, challenges such as intracellular interferences and insufficient detection limits still remain. In this work, an ultrasensitive nanopore sensor for quantitative single-cell miRNA-155 detection is constructed based on ionic current rectification (ICR) coupled with enzyme-free catalytic hairpin assembly (CHA). Benefiting from the enzyme-free CHA amplification strategy, the detection limit of the nanopore sensor for miRNA-155 reaches 10 fM and the nanopore sensor is more adaptable to complex intracellular environments. With the nanopore sensor, the concentration of miRNA-155 in living single cells is quantified to realize the early diagnosis of triple-negative breast cancer (TNBC). Furthermore, the nanopore sensor can be applied in screening anticancer drugs by tracking the expression level of miRNA-155. This work provides an adaptive and universal method for quantitatively analyzing intracellular miRNAs, which will greatly improve our understanding of cell heterogeneity and provide a more reliable scientific basis for exploring major diseases at the single-cell level.


Assuntos
MicroRNAs , Nanoporos , Análise de Célula Única , Neoplasias de Mama Triplo Negativas , MicroRNAs/análise , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Humanos , Feminino , Linhagem Celular Tumoral , Limite de Detecção
5.
Plant Physiol ; 194(1): 391-407, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-37738410

RESUMO

Exposure of dark-grown etiolated seedlings to light triggers the transition from skotomorphogenesis/etiolation to photomorphogenesis/de-etiolation. In the life cycle of plants, de-etiolation is essential for seedling development and plant survival. The mobilization of soluble sugars (glucose [Glc], sucrose, and fructose) derived from stored carbohydrates and lipids to target organs, including cotyledons, hypocotyls, and radicles, underpins de-etiolation. Therefore, dynamic carbohydrate biochemistry is a key feature of this phase transition. However, the molecular mechanisms coordinating carbohydrate status with the cellular machinery orchestrating de-etiolation remain largely opaque. Here, we show that the Glc sensor HEXOKINASE 1 (HXK1) interacts with GROWTH REGULATOR FACTOR5 (GRF5), a transcriptional activator and key plant growth regulator, in Arabidopsis (Arabidopsis thaliana). Subsequently, GRF5 directly binds to the promoter of phytochrome A (phyA), encoding a far-red light (FR) sensor/cotyledon greening inhibitor. We demonstrate that the status of Glc within dark-grown etiolated cotyledons determines the de-etiolation of seedlings when exposed to light irradiation by the HXK1-GRF5-phyA molecular module. Thus, following seed germination, accumulating Glc within dark-grown etiolated cotyledons stimulates a HXK1-dependent increase of GRF5 and an associated decrease of phyA, triggering the perception, amplification, and relay of HXK1-dependent Glc signaling, thereby facilitating the de-etiolation of seedlings following light irradiation. Our findings, therefore, establish how cotyledon carbohydrate signaling under subterranean darkness is sensed, amplified, and relayed, determining the phase transition from skotomorphogenesis to photomorphogenesis on exposure to light irradiation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Plântula/metabolismo , Cotilédone/metabolismo , Estiolamento , Glucose/metabolismo , Luz , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fitocromo A/metabolismo , Regulação da Expressão Gênica de Plantas
6.
Opt Lett ; 49(20): 5687-5690, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39404513

RESUMO

A scheme to construct analogical atoms using graphene nanostructures via quantum nonlinearity is proposed. Due to the strong field localization capability of graphene plasmons and the significant intrinsic nonlinearity of graphene, a strong nonlinear optical response can be realized even with single-photon excitation. In this process, the quantum vacuum localized plasmonic mode plays a crucial role in achieving the third-order multi-photon nonlinear effect. The eigenfrequency of the nanostructure can shift by an amount tens of times larger than the decay rate, causing the nanostructure cavity to exhibit atomic-like behaviors. Furthermore, multilevel atoms can be constructed through the interaction of composite graphene nanostructures. The parameters of these atoms can be manipulated by adjusting the nanostructure size, Fermi energy, and other parameters. This research holds significant potential for applications in highly integrated, controllable nanophotonics.

7.
Opt Lett ; 49(20): 5679-5682, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39404511

RESUMO

Integral imaging (InIm) working with a pixelated device (e.g., a display panel) and a microlens array (MLA) suffers from low spatial resolution because of a significant trade-off between the spatial and angular resolution. The system bandwidth is presumed to be limited by the Nyquist frequency set by the pixel pitch. This study demonstrates that InIm intrinsically works in an incoherent synthetic aperture (ISA) manner with unexploited resolution capabilities. The sampling shifts between lenslets can be controlled and utilized to construct "computational galvos" to introduce varying aliasing; as a result, the Nyquist frequency is broken for optical super-resolution (SR). In particular, an InIm system can be configured for an N-fold oversampling rate with N lenslets. Furthermore, in an InIm display, the fill factor of a pixel's emitting area is always lower than 100%, so the bandwidth limit set by the pixel shape, i.e., two times the Nyquist frequency, is loosened. An InIm display prototype was built with an oversampling rate of four and a pixel fill factor of 75%. In the experiment, the proposed SR method achieved a 2.12 times resolution without dynamic devices or time-multiplexing.

8.
Nitric Oxide ; 152: 19-30, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39260562

RESUMO

The mutual regulation between hydrogen sulfide (H2S) and microRNA (miRNA) is involved in the development of many diseases, including cancer, cardiovascular disease, inflammatory disease, and high-risk pregnancy. Abnormal expressions of endogenous H2S-producing enzyme and miRNA in tissues and cells often indicate the occurrence of diseases, so the maintenance of their normal levels in the body can mitigate damages caused by various factors. Many studies have found that H2S can promote the migration, invasion, and proliferation of cancer cells by regulating the expression of miRNA, while many H2S donors can inhibit cancer progression by interfering with the proliferation, apoptosis, cell cycle, metastasis, and angiogenesis of cancer cells. Furthermore, the mutual regulation between H2S and miRNA can also prevent cell injury in cardiovascular disease and inflammatory disease through anti-inflammation, anti-oxidation, anti-apoptosis, and pro-autophagy. In addition, H2S can promote angiogenesis and relieve vasoconstriction by regulating the expression of miRNA, thereby improving fetal growth in high-risk pregnancy. In this review, we discuss the mechanism of mutual regulation between H2S and miRNA in various diseases, which may provide reliable therapeutic targets for these diseases.


Assuntos
Doenças Cardiovasculares , Sulfeto de Hidrogênio , MicroRNAs , Neoplasias , Sulfeto de Hidrogênio/metabolismo , Humanos , MicroRNAs/metabolismo , Doenças Cardiovasculares/metabolismo , Neoplasias/metabolismo , Neoplasias/genética , Animais , Inflamação/metabolismo , Feminino , Gravidez
9.
Biochem Biophys Res Commun ; 652: 88-94, 2023 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-36841099

RESUMO

Acetaminophen (APAP) overdose is the most common cause for acute liver failure (ALF) in the developed countries, with limited treatment options. Piezo1 is a mechanosensitive cation channel. We found that APAP caused upregulation of Piezo1 in both an APAP-induced acute liver injury (ALI) animal model and a mouse hepatocyte cell line AML12. Activation of Piezo1 by its activator Yoda1 reduced APAP-induced hepatotoxicity and ROS level. Mechanistically, activation of Piezo1 led to accumulation of the antioxidant regulator Nrf2 and upregulation of its target genes Nqo1 and Gsta1, while knockdown of Piezo1 downregulated this pathway. Finally, injection of Yoda1 decreased serum AST and ALT levels, reduced cell death and rescued liver injury in the APAP-induced ALI mouse model. Our findings suggested a previously undiscovered protective role of Piezo1 in APAP-induced ALI, which might shed light on a new therapeutic target for this disease.


Assuntos
Acetaminofen , Doença Hepática Induzida por Substâncias e Drogas , Animais , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fígado/metabolismo , Hepatócitos/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Estresse Oxidativo , Camundongos Endogâmicos C57BL , Canais Iônicos/metabolismo
10.
Appl Opt ; 62(15): 3967-3975, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37706707

RESUMO

In this paper, we implement integrated magnetic flux concentrators (MFCs) combined with a multi-frequency modulation method to achieve high-magnetic-detection sensitivity using a nuclear spin on the solid nuclear spin in diamonds. First, we excited the nuclear spin in diamonds using a continuous-wave technique, and a linewidth of 1.37 MHz and frequency resolution of 79 Hz were successfully obtained, which is reduced by one order of the linewidth, and increased by 56 times in frequency resolution compared to that excited by an electron spin. The integrated high-permeability MFC was designed to magnify the magnetic field near the diamond, with a magnification of 9.63 times. Then, the multi-frequency modulation technique was used to fully excite the hyperfine energy level of Nitrogen Vacancy (NV) centers along the four axes on the diamond with MFC, and magnetic detection sensitivity of 250p T/H z 1/2 was realized. These techniques should allow designing an integrated NV magnetometer with high sensitivity in a small volume.

11.
Altern Ther Health Med ; 29(7): 400-403, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37535914

RESUMO

Objectives: To investigate the influence of helper T cell type 1 (Th1)/Th2 cytokines and Treg cells on the pregnancy outcome of patients with recurrent pregnancy loss (RPL) and to reveal the predictive value of their combination on the pregnancy outcome. Methods: The 165 RPL patients admitted to the Reproductive Medicine Department of the Second Hospital of Lanzhou University from September 2019 to June 2021 served as the research subjects for the study. The subjects comprised a live birth group (102 patients) or a non-live birth group (63 patients) based on their pregnancy outcomes. All patients were tracked through the end of pregnancy. Flow cytometry was applied to determine Treg and Th1/Th2 cytokine levels in the peripheral blood of patients without pregnancy. Results: The levels of interleukin-6 (IL-6), IL-2, IL-10, and Treg in the RPL live birth group were significantly higher than those in the non-live birth group. The ratio of TNF - α/ IL-6, NF-α/ IL-10, IFN- γ/ IL-6, IFN- γ/ IL-10 in the non-live birth group increased significantly. The area under the curve (AUC) of Th1/Th2 cytokines combined with Treg cells was 0.786 (95% CI: 0.712-0.860), the specificity was 76.2%, and the sensitivity was 74.5%. Conclusion: Treg and Th1/Th2 cytokines showed a predictive ability for the pregnancy outcome of patients with recurrent pregnancy loss and their higher combined predictive efficacy. Meanwhile, in the Th1/Th2 immune response, its ratio was more important than the expression of a single cytokine.


Assuntos
Aborto Habitual , Citocinas , Feminino , Gravidez , Humanos , Citocinas/metabolismo , Resultado da Gravidez , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Linfócitos T Reguladores/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Aborto Habitual/metabolismo
12.
Chemistry ; 27(24): 7080-7084, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33769604

RESUMO

Double cross-linked dynamic hydrogels, dynagels, have been prepared through reversible imine bonds and supramolecular interactions, which showed good pH responsiveness, injectability, self-healing property and biocompatibility. With the further encapsulation of heparin, the obtained hydrogels exhibited good anti-bacterial activity and promotion effects for 3D cell culture.


Assuntos
Heparina , Hidrogéis , Técnicas de Cultura de Células
13.
Eur Radiol ; 31(7): 4669-4679, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33416975

RESUMO

OBJECTIVE: To investigate the correlation of intravoxel incoherent motion (IVIM) and diffusion kurtosis imaging (DKI) parameters with the expression of HIF-1α in soft tissue sarcoma (STS). METHODS: This prospective study was approved by the institutional ethics committee. Written informed consent was obtained from all patients. Forty patients with STS who underwent 3.0 T MRI, including IVIM and DKI, were included in the study. Standard apparent diffusion coefficient (ADC), true ADC (Dslow), pseudo ADC (Dfast), perfusion fraction (f), mean kurtosis (MK), and mean diffusivity (MD) of each lesion were independently analyzed by two observers. An MRI-pathology control method was used to ensure correspondence between the MRI slices and the pathological sections. Spearman analysis, independent sample t test, Mann-Whitney U test, chi-squared test, and receiver operating characteristic (ROC) curve analysis were performed. RESULTS: Dslow and MD values showed a negative correlation with HIF-1α expression (r = - 0.469, - 0.588). MK and f values showed a positive correlation with HIF-1α expression (r = 0.779, 0.572). Dslow, MD, MK, and f values showed significant differences between the high- and low-expression groups. The MK value showed the best diagnostic ability. The optimal cut-off MK value of 0.604 was associated with 78.3% sensitivity and 88.2% specificity (area under the curve, 0.867). CONCLUSIONS: This preliminary study demonstrated the association of IVIM and DKI parameters with the expression of HIF-1α in STS. KEY POINTS: • IVIM and DKI parameters are correlated with the expression of HIF-1α in STS. • The MRI-pathology control method can be used in clinical studies to ensure correspondence between MRI slices and pathology sections.


Assuntos
Imagem de Tensor de Difusão , Sarcoma , Imagem de Difusão por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética , Movimento (Física) , Estudos Prospectivos , Sarcoma/diagnóstico por imagem , Sensibilidade e Especificidade
14.
Ecotoxicol Environ Saf ; 212: 112012, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33550074

RESUMO

Microplastics (MPs) considered as a new persistent environmental pollutant could enter into the circulatory system and result in decrease of sperm quantity and quality in mice. However, the effects of Polystyrene MPs (PS MPs) on the ovary and its mechanism in rats remained unclear. In this present study, thirty-two healthy female Wistar rats were exposed to different concentrations of 0.5 µm PS MPs dispersed in deionized water for 90 days. Using hematoxylin-eosin (HE) staining, the number of growing follicles was decreased compared to the control group. In addition, the activity of glutathione peroxidase (GSH-Px), catalase (CAT) and superoxide dismutase (SOD) were decreased while the expression level of malondialdehyde (MDA) was increased in ovary tissue. Confirmed by immunohistochemistry, the integrated optical density of NLRP3 and Cleaved-Caspase-1 had been elevated by 13.9 and 14 in granulosa cells in the 1.5 mg/kg/d group. Furthermore, compared to the control group, the level of AMH had been decreased by 23.3 pg/ml while IL-1ß and IL-18 had been increased by 32 and 18.5 pg/ml in the 1.5 mg/kg/d group using the enzyme-linked immune sorbent assay (ELISA). Besides, the apoptosis of granulosa cells was elevated measured by terminal deoxyribonucleotide transferase-mediated nick end labeling (TUNEL) staining and flow cytometry. Moreover, western blot assays showed that the expressions of NLRP3/Caspase-1 signaling pathway related factors and Cleaved-Caspase-3 were increased. These results demonstrated that PS MPs could induce pyroptosis and apoptosis of ovarian granulosa cells via the NLRP3/Caspase-1 signaling pathway maybe triggered by oxidative stress. The present study suggested that exposure to microplastics had adverse effects on ovary and could be a potential risk factor for female infertility, which provided new insights into the toxicity of MPs on female reproduction.


Assuntos
Apoptose/efeitos dos fármacos , Caspase 1/metabolismo , Microplásticos/toxicidade , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ovário/efeitos dos fármacos , Poliestirenos/toxicidade , Piroptose/efeitos dos fármacos , Animais , Feminino , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Células da Granulosa/patologia , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Malondialdeído/metabolismo , Ovário/metabolismo , Ovário/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Transdução de Sinais
15.
Int J Mol Sci ; 22(23)2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34884572

RESUMO

Autophagy is a highly conserved process of the eukaryotic cell cycle. It plays an important role in the survival and maintenance of cells by degrading organelles, proteins, and macromolecules in the cytoplasm and the circulation of degraded products. The dysfunction of autophagy can lead to the pathology of many human diseases. The nucleotide-binding oligomerization domain-like receptor family, pyrin domain-containing 3 (NLRP3) inflammasome belongs to the family of nucleotide-binding and oligomerization domain-like receptors (NLRs) and can induce caspase-1 activation, thus leading to the maturation and secretion of interleukin-1beta (IL-1ß) and IL-18. It has been reported that the interplay between autophagy and NLRP3 inflammasome is involved in many diseases, including renal diseases. In this review, the interplay between autophagy and the NLRP3 inflammasome and the mechanisms in renal diseases are explored to provide ideas for relevant basic research in the future.


Assuntos
Autofagia , Inflamassomos/metabolismo , Nefropatias/patologia , Animais , Humanos , Nefropatias/etiologia , Nefropatias/metabolismo
16.
Appl Opt ; 59(20): 6203-6209, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32672768

RESUMO

An important goal in designing a head-mounted display device is to improve its exit pupils' output light areal uniformity. The goal cannot be reached by using an output grating coupler of uniform surface profile depth. To solve this problem, we propose a method to fabricate 2D and continuously variable depth gratings by using a specially modified reactive ion-beam etching system, which features variable speed scanning etching and ion beam cross-sectional shaping in two orthogonal dimensions. We experimentally verified that the uniformity of the light outcoupled from the coupler fabricated by using the proposed method was 52% better than that of a uniform-depth output grating coupler.

17.
Skeletal Radiol ; 49(11): 1829-1838, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32519183

RESUMO

OBJECTIVE: To determine if dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) parameters reflect histological grade of soft tissue sarcoma (STS) MATERIALS AND METHODS: The medical records of 50 patients diagnosed with pathologically confirmed STS were retrospectively reviewed. Each STS was assessed with conventional contrast-enhanced MRI and DCE-MRI using a 3.0-T MRI system. The conventional MRI characteristics of low-grade (grade 1) and high-grade (grade 2 and grade 3) tumors were analyzed. Semi-quantitative parameters, including iAUC and TTP, and quantitative parameters, including Ktrans, Kep, and Ve, were derived from DCE-MRI. The diagnostic performances and optimal thresholds of various combinations of DCE-MRI parameters for predicting histological grades of STS were investigated using receiver operator characteristic (ROC) curves. RESULTS: On conventional MRI, high-grade STSs were significantly larger (≥ 5 cm) and more likely to show a heterogeneous signal intensity on T2WI (> 75%), peritumoral hyperintensity on T2WI, or tumor necrosis (> 50%) compared with low-grade STS. On DCE-MRI, iAUC, TTP, Ktrans, and Kep were significant predictors of STS histological grade. Ktrans had a high diagnostic value for differentiating between high-grade and low-grade STSs. The combination of iAUC, TTP, and Ktrans yielded a higher AUC value (0.841) than the other models. CONCLUSION: High-grade STSs were usually larger than low-grade STSs, had unclear boundaries, a heterogeneous signal intensity on T2-weighted image (T2WI), and extensive necrosis. On DCE-MRI, iAUC, TTP, Ktrans, and Kep could differentiate between high-grade and low-grade STSs. The combination of iAUC, TTP, and Ktrans had a high diagnostic performance for differentiating between STS histological grades.


Assuntos
Imageamento por Ressonância Magnética , Sarcoma , Neoplasias de Tecidos Moles , Meios de Contraste , Humanos , Estudos Retrospectivos , Sarcoma/diagnóstico por imagem , Neoplasias de Tecidos Moles/diagnóstico por imagem
18.
Cell Biol Int ; 40(5): 560-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26861731

RESUMO

Some ingredients in foods can activate the aryl hydrocarbon receptor (AhR) and arrest cell proliferation. In this study, we hypothesized that 6-formylindolo [3, 2-b] carbazole (FICZ) arrests the cell cycle in LoVo cells (a colon cancer line) through the AhR. The AhR agonist FICZ and the AhR antagonist CH223191 were used to treat LoVo cells. Real-time PCR and Western blot analyses were performed to detect the expression of the AhR, CYP1A1, CDK4, cyclinD1, cyclin E, CDK2, P27, and pRb. The distribution and activation of the AhR were detected with immunofluorescence. A 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay and flow cytometric analysis were performed to measure cell viability, cell cycle stage, and apoptosis. Our results show that FICZ inhibited LoVo cell proliferation by inducing G1 cell cycle arrest but had no effect on epithelial apoptosis. Further analysis found that FICZ downregulated cyclinD1 and upregulated p27 expression to arrest Rb phosphorylation. The downregulation of cyclinD1 and upregulation of p27 were abolished by co-treatment with CH223191. We conclude that the AhR, when activated by FICZ (an endogenous AhR ligand), can arrest the cell cycle and block LoVo cell proliferation.


Assuntos
Carbazóis/farmacologia , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Receptores de Hidrocarboneto Arílico/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Ciclina D1/efeitos dos fármacos , Ciclina D1/genética , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Humanos , Proteínas de Membrana/metabolismo , Fosforilação , Receptores de Hidrocarboneto Arílico/agonistas , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos
19.
Dig Dis Sci ; 61(2): 444-52, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26514676

RESUMO

BACKGROUND: Keratinocyte growth factor (KGF) stimulates normal growth, development and intestinal epithelial cell proliferation. Cyclin D1 promotes the cell cycle by inhibiting retinoblastoma protein (RB1). The activated aryl hydrocarbon receptor (AhR) has an important influence on the development of tumors through its interactions with the cell cycle. AIM: The aim of the present study was to explore a new role for AhR in KGF-induced colon cancer cell growth. MATERIALS AND METHODS: Real-time PCR, western blot or immunofluorescence analysis were used to detect the expression of KGF, AhR, cyclin D1 and CYP1A1. Immunohistochemistry was used to observe the localization of AhR. MTT assay and flow cytometric analyses were performed to measure cell viability and the cell cycle. RESULTS: Real-time PCR analysis revealed that KGF, AhR, and CYP1A1 mRNAs were overexpressed in colorectal cancer tissues. Meanwhile, overexpression of AhR was primarily observed in epithelial cells. In in vitro assay, KGF promoted colon cancer cell growth, as well as up-regulated and activated AhR. At the same time, AhR-knockdown colon cancer cells were less responsive to KGF. Western blot analysis, real-time PCR, or immunofluorescence data indicated that cyclin D1 expression was up-regulated by KGF but this up-regulation was compromised when AhR was silenced, and the cell cycle was arrested in the G0/G1 stage in these cells. CONCLUSIONS: Our study suggests that KGF, AhR, and CYP1A1 are overexpressed in colorectal cancer tissues. Moreover, we reveal a new mechanism by which KGF promotes cell proliferation through the AhR-cyclin D1 pathway in colon cancer cells.


Assuntos
Neoplasias Colorretais/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Fator 7 de Crescimento de Fibroblastos/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/genética , Ciclina D1 , Citocromo P-450 CYP1A1/genética , Fator 7 de Crescimento de Fibroblastos/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Técnicas de Silenciamento de Genes , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Hidrocarboneto Arílico/genética
20.
Adv Sci (Weinh) ; 11(11): e2307872, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38178606

RESUMO

Aqueous zinc-ion batteries (AZIBs) are considered as attractive energy storage systems with great promise owing to their low cost, environmental friendliness and high safety. Nevertheless, cathode materials with stable structure and rapid diffusion of zinc ions are in great demand for AZIBs. In this work, a new kind of potassium vanadate compound (KV3 O8 ) is synthesized with fibrous morphology as an excellent cathode material for AZIBs, which shows outstanding electrochemical performance. KV3 O8 exhibits a high discharge capacity of 556.4 mAh g-1 at 0.8 A g-1 , and the capacity retention is 81.3% at 6 A g-1 even after a long cycle life of 5000 cycles. The excellent performance of the KV3 O8 cathode is benefited from the structural stability, sufficient active sites, and high conductivity, which is revealed by in situ X-ray diffraction and various other characterizations. This work offers a new design strategy into fabricating high efficiency cathode materials for AZIBs and beyond.

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