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1.
Nature ; 572(7769): 363-367, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31341282

RESUMO

Quantum computers can efficiently solve classically intractable problems, such as the factorization of a large number1 and the simulation of quantum many-body systems2,3. Universal quantum computation can be simplified by decomposing circuits into single- and two-qubit entangling gates4, but such decomposition is not necessarily efficient. It has been suggested that polynomial or exponential speedups can be obtained with global N-qubit (N greater than two) entangling gates5-9. Such global gates involve all-to-all connectivity, which emerges among trapped-ion qubits when using laser-driven collective motional modes10-14, and have been implemented for a single motional mode15,16. However, the single-mode approach is difficult to scale up because isolating single modes becomes challenging as the number of ions increases in a single crystal, and multi-mode schemes are scalable17,18 but limited to pairwise gates19-23. Here we propose and implement a scalable scheme for realizing global entangling gates on multiple 171Yb+ ion qubits by coupling to multiple motional modes through modulated laser fields. Because such global gates require decoupling multiple modes and balancing all pairwise coupling strengths during the gate, we develop a system with fully independent control capability on each ion14. To demonstrate the usefulness and flexibility of these global gates, we generate a Greenberger-Horne-Zeilinger state with up to four qubits using a single global operation. Our approach realizes global entangling gates as scalable building blocks for universal quantum computation, motivating future research in scalable global methods for quantum information processing.

2.
Gut ; 73(3): 470-484, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38050068

RESUMO

OBJECTIVE: Metastasis is the major cause of cancer death. However, what types of heterogenous cancer cells in primary tumour and how they metastasise to the target organs remain largely undiscovered. DESIGN: We performed single-cell RNA sequencing and spatial transcriptomic analysis in primary colorectal cancer (CRC) and metastases in the liver (lCRC) or ovary (oCRC). We also conducted immunofluorescence staining and functional experiments to examine the mechanism. RESULTS: Integrative analyses of epithelial cells reveal a stem-like cell cluster with high protein tyrosine phosphatase receptor type O (PTPRO) and achaete scute-like 2 (ASCL2) expression as the metastatic culprit. This cell cluster comprising distinct subpopulations shows distinct liver or ovary metastatic preference. Population 1 (P1) cells with high delta-like ligand 4 (DLL4) and MAF bZIP transcription factor A (MAFA) expression are enriched in primary CRC and oCRC, thus may be associated with ovarian metastasis. P3 cells having a similar expression pattern as cholangiocytes are found mainly in primary CRC and lCRC, presuming to be likely the culprits that specifically metastasise to the liver. Stem-like cells interacted with cancer-associated fibroblasts and endothelial cells via the DLL4-NOTCH signalling pathway to metastasise from primary CRC to the ovary. In the oCRC microenvironment, myofibroblasts provide cancer cells with glutamine and perform a metabolic reprogramming, which may be essential for cancer cells to localise and develop in the ovary. CONCLUSION: We uncover a mechanism for organ-specific CRC metastasis.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Feminino , Humanos , Neoplasias Colorretais/patologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Neoplasias Hepáticas/patologia , Perfilação da Expressão Gênica , Transdução de Sinais/genética , Regulação Neoplásica da Expressão Gênica , Metástase Neoplásica/genética , Microambiente Tumoral/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo
3.
Plant Cell Environ ; 47(7): 2443-2458, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38557938

RESUMO

The GSK3/SHAGGY-like kinase plays critical roles in plant development and response to stress, but its specific function remains largely unknown in wheat (Triticum aestivum L.). In this study, we investigated the function of TaGSK3, a GSK3/SHAGGY-like kinase, in wheat development and response to stress. Our findings demonstrated that TaGSK3 mutants had significant effects on wheat seedling development and brassinosteroid (BR) signalling. Quadruple and quintuple mutants showed amplified BR signalling, promoting seedling development, while a sextuple mutant displayed severe developmental defects but still responded to exogenous BR signals, indicating redundancy and non-BR-related functions of TaGSK3. A gain-of-function mutation in TaGSK3-3D disrupted BR signalling, resulting in compact and dwarf plant architecture. Notably, this mutation conferred significant drought and heat stress resistance of wheat, and enhanced heat tolerance independent of BR signalling, unlike knock-down mutants. Further research revealed that this mutation maintains a higher relative water content by regulating stomatal-mediated water loss and maintains a lower ROS level to reduces cell damage, enabling better growth under stress. Our study provides comprehensive insights into the role of TaGSK3 in wheat development, stress response, and BR signal transduction, offering potential for modifying TaGSK3 to improve agronomic traits and enhance stress resistance in wheat.


Assuntos
Brassinosteroides , Proteínas de Plantas , Transdução de Sinais , Estresse Fisiológico , Triticum , Triticum/genética , Triticum/fisiologia , Triticum/crescimento & desenvolvimento , Brassinosteroides/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Secas , Regulação da Expressão Gênica de Plantas , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Plântula/genética , Adaptação Fisiológica/genética , Mutação , Espécies Reativas de Oxigênio/metabolismo
4.
Opt Lett ; 49(13): 3749-3752, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950258

RESUMO

Underwater communication and positioning are essential for autonomous underwater vehicle (AUV) docking and formation. The traditional methods for communication and positioning are mainly independent from each other, increasing the redundancy and integration difficulty for AUVs. In this Letter, we demonstrate a real-time underwater wireless optical communication and positioning (UWOCP) integrated system. The LED array is adopted as a light source, and the pulse-position modulation (PPM) is used for a maximum transmission and sensing distance. By employing the silicon photomultiplier (SiPM) array, which consists of five SiPMs with different angles, the high sensitivity and ability to distinguish angles are obtained. Through calculating the relationship between the received pulse signal intensity of the five SiPMs, the pitch angle and yaw angle can be obtained. The experimental results in the pool show that the Ethernet bandwidth of 2.2 Mbps with an average angular error of 3.08° for one-dimensional positioning can be realized at a 50 m distance. To the best of our knowledge, this is the longest distance at which a real-time UWOCP system has been demonstrated. The proposed UWOCP system has the advantages of high sensitivity, computing efficiency, and compact structure, presenting great potential for underwater applications.

5.
J Nanobiotechnology ; 22(1): 179, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38616270

RESUMO

We report on the fabrication of mesoporous silicon dioxide coated Haliclona sp. spicules (mSHS) to enhance the delivery of the insoluble photosensitizer protoporphyrin IX (PpIX) into deep skin layers and mediate photodynamic therapy for metastatic melanoma in mice. The mSHS are dispersed sharp edged and rod-like micro-particles with a length of approximate 143.6 ± 6.4 µm and a specific surface area of 14.9 ± 3.4 m2/g. The mSHS can be topically applied to the skin, adapting to any desired skin area and lesion site. The insoluble PpIX were incorporated into the mesoporous silica coating layers of mSHS (mSHS@PpIX) with the maximum PpIX loading capacity of 120.3 ± 3.8 µg/mg. The mSHS@PpIX significantly enhanced the deposition of PpIX in the viable epidermis (5.1 ± 0.4 µg/cm2) and in the dermis (0.5 ± 0.2 µg/cm2), which was 154 ± 11-fold and 22 ± tenfold higher than those achieved by SHS, respectively. Topical delivery of PpIX using mSHS (mSHS@PpIX) completely eradicated the primary melanoma in mice in 10 days without recurrence or metastasis over 60 days. These results demonstrate that mSHS can be a promising topical drug delivery platform for the treatment of diverse cutaneous diseases, such as metastatic melanoma.


Assuntos
Melanoma , Fotoquimioterapia , Animais , Camundongos , Melanoma/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Pele , Dióxido de Silício
6.
Appl Opt ; 63(8): 2030-2035, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38568644

RESUMO

Multimode power splitters are the fundamental building blocks in mode division multiplexing systems. In this paper, we propose a low-loss and compact, dual-mode, 3-dB power splitter for the two lowest TE modes combining three different structures, including a directional coupler, a multimode interferometer, and a Y-junction. The coupling length of the proposed device is only 7.2 µm. For both T E 0 and T E 1 modes, the numerical simulation shows that the insertion loss is only less than 0.1 dB and crosstalk is less than -20d B at the wavelength range of 1520-1580 nm. The working bandwidth can cover the entire C-band. It offers a potential solution for a 3-dB power splitter of the two lowest TE modes.

7.
Anim Biotechnol ; 35(1): 2356110, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38804592

RESUMO

The inducing activation event of secondary hair follicle (SHF)-stem cells is considered a key biological process in the SHF regeneration, and the morphogenesis of cashmere fiber in cashmere goats. The miR-361-5p was essentially implicated in the induced activation of SHF-stem cells of cashmere goats, but its functional mechanisms are unclear. Here, we confirmed miR-361-5p was significantly downregulated in anagen SHF bugle of cashmere goats compared with that at telogen, and miR-361-5p expression was significantly lower in SHF-stem cells after activation than its counterpart before activation. Further, we found that miR-361-5p could negatively regulate the induced activation event of SHF-stem cells in cashmere goats. Mechanistically, through dual-luciferase reporter assays, miR-361-5p specifically bound with FOXM1 mRNA in SHF-stem cells of cashmere goats and negatively regulated the expression of FOXM1 gene. Also, through overexpression/knockdown analysis of FOXM1 gene, our results indicated that FOXM1 upregulated the expression of Wnt/ß-catenin pathway related genes in SHF-stem cells. Moreover, based on TOP/FOP-flash Wnt report assays, the knockdown of miR-361-5p promotes the Wnt/ß-catenin pathway activation through upregulating the FOXM1 expression in SHF-stem cells. Finally, we demonstrated that miR-361-5p negatively regulated the induced activation of SHF-stem cells through FOXM1 mediated Wnt/ß-catenin pathway in cashmere goats.


Assuntos
Proteína Forkhead Box M1 , Cabras , Folículo Piloso , MicroRNAs , Células-Tronco , Via de Sinalização Wnt , Animais , Cabras/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Via de Sinalização Wnt/genética , Folículo Piloso/metabolismo , Proteína Forkhead Box M1/genética , Proteína Forkhead Box M1/metabolismo , Células-Tronco/fisiologia , Células-Tronco/metabolismo , Técnicas de Silenciamento de Genes
8.
Sensors (Basel) ; 24(5)2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38475191

RESUMO

The utilization of downhole optical cables has significantly enhanced the efficiency and reliability of oilfield production operations; however, the challenging high-temperature and high-pressure conditions prevalent in oil-gas fields markedly reduce the service lifespan of these optical cables. This limitation severely impedes their application and further development in subterranean environments. In this study, a qualitative analysis was conducted on the structural materials utilized in two types of optical cables to identify these materials and assess the high-temperature tolerance and aging resistance properties of the optical fibers incorporated within. It was discovered that hydrogen infiltration into the subterranean optical cables predominantly accounts for their operational failure. To address this issue, an optical loss testing platform was established, facilitating the execution of a high-temperature and high-pressure hydrogen permeation aging experiment on the optical fibers, allowing for the evaluation of the hydrogen resistance capabilities of the two types of optical fibers. The findings from this study provide a theoretical foundation and methodological guidance for the optimization of optical fibers, aiming to enhance their durability and functional performance in adverse environmental conditions encountered in oil-gas field applications.

9.
Molecules ; 29(8)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38675674

RESUMO

The water produced during the oxidative esterification reaction occupies the active sites and reduces the activity of the catalyst. In order to reduce the influence of water on the reaction system, a hydrophobic catalyst was prepared for the one-step oxidative esterification of methylacrolein (MAL) and methanol. The catalyst was synthesized by loading the active component Au onto ZnO using the deposition-precipitation method, followed by constructing the silicon shell on Au/ZnO using tetraethoxysilane (TEOS) to introduce hydrophobic groups. Trimethylchlorosilane (TMCS) was used as a hydrophobic modification reagent to prepare hydrophobic catalysts, which exhibited a water droplet contact angle of 111.2°. At a temperature of 80 °C, the hydrophobic catalyst achieved a high MMA selectivity of over 95%. The samples were characterized using XRD, N2 adsorption, ICP, SEM, TEM, UV-vis, FT-IR, XPS, and water droplet contact angle measurements. Kinetic analysis revealed an activation energy of 22.44 kJ/mol for the hydrophobic catalyst.

10.
Small ; 19(15): e2206463, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36609999

RESUMO

Bioinspired smart superwetting surfaces with special wettability have aroused great attention from fundamental research to technological applications including self-cleaning, oil-water separation, anti-icing/corrosion/fogging, drag reduction, cell engineering, liquid manipulation, and so on. However, most of the reported smart superwetting surfaces switch their wettability by reversibly changing surface chemistry rather than surface microstructure. Compared with surface chemistry, the regulation of surface microstructure is more difficult and can bring novel functions to the surfaces. As a kind of stimulus-responsive material, shape-memory polymer (SMP) has become an excellent candidate for preparing smart superwetting surfaces owing to its unique shape transformation property. This review systematically summarizes the recent progress of smart superwetting SMP surfaces including fabrication methods, smart superwetting phenomena, and related application fields. The smart superwettabilities, such as superhydrophobicity/superomniphobicity with tunable adhesion, reversible switching between superhydrophobicity and superhydrophilicity, switchable isotropic/anisotropic wetting, slippery surface with tunable wettability, and underwater superaerophobicity/superoleophobicity with tunable adhesion, can be obtained on SMP micro/nanostructures by regulating the surface morphology. Finally, the challenges and future prospects of smart superwetting SMP surfaces are discussed.

11.
Mol Ther ; 30(3): 1089-1103, 2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-34995801

RESUMO

N6-methyladenosine (m6A) is the most prevalent RNA modification, and the effect of its dysregulation on esophageal squamous cell carcinoma (ESCC) development remains unclear. Here, by performing transcriptome-wide m6A sequencing in 16 ESCC tissue samples, we identified the key roles of m6A in TNFRSF1A (also known as TNFR1)-mediated MAPK and NF-κB activation in ESCC. Mechanistically, a functional protein involved in m6A methylation, ATXN2, is identified that augments the translation of TNFRSF1A by binding to m6A-modified TNFRSF1A mRNA. Upregulation of the TNFRSF1A protein level, a vital upstream switch for TNFRSF1A-mediated signaling events, activates the NF-κB and MAPK pathways and thus promotes ESCC development. Furthermore, TNFRSF1A m6A modifications and protein levels are upregulated in ESCC, and high levels of TNFRSF1A m6A and protein are correlated with poor ESCC patient survival. These results collectively indicate that the m6A-TNFRSF1A axis is critical for ESCC development and thus may serve as a potential druggable target.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Ataxina-2/genética , Ataxina-2/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , NF-kappa B/metabolismo , RNA Mensageiro/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética
12.
Sensors (Basel) ; 23(13)2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37447626

RESUMO

This paper introduces a simple but effective image filtering method, namely, local adaptive image filtering (LAIF), based on an image segmentation method, i.e., recursive dilation segmentation (RDS). The algorithm is motivated by the observation that for the pixel to be smoothed, only the similar pixels nearby are utilized to obtain the filtering result. Relying on this observation, similar pixels are partitioned by RDS before applying a locally adaptive filter to smooth the image. More specifically, by directly taking the spatial information between adjacent pixels into consideration in a recursive dilation way, RDS is firstly proposed to partition the guided image into several regions, so that the pixels belonging to the same segmentation region share a similar property. Then, guided by the iterative segmented results, the input image can be easily filtered via a local adaptive filtering technique, which smooths each pixel by selectively averaging its local similar pixels. It is worth mentioning that RDS makes full use of multiple integrated information including pixel intensity, hue information, and especially spatial adjacent information, leading to more robust filtering results. In addition, the application of LAIF in the remote sensing field has achieved outstanding results, specifically in areas such as image dehazing, denoising, enhancement, and edge preservation, among others. Experimental results show that the proposed LAIF can be successfully applied to various filtering-based tasks with favorable performance against state-of-the-art methods.


Assuntos
Processamento de Imagem Assistida por Computador , Algoritmos , Processamento de Imagem Assistida por Computador/métodos
13.
Entropy (Basel) ; 25(7)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37509945

RESUMO

Most Heterogeneous Information Network (HIN) embedding methods use meta-paths to guide random walks to sample from HIN and perform representation learning in order to overcome the bias of traditional random walks that are more biased towards high-order nodes. Their performance depends on the suitability of the generated meta-paths for the current HIN. The definition of meta-paths requires domain expertise, which makes the results overly dependent on the meta-paths. Moreover, it is difficult to represent the structure of complex HIN with a single meta-path. In a meta-path guided random walk, some of the heterogeneous structures (e.g., node type(s)) are not among the node types specified by the meta-path, making this heterogeneous information ignored. In this paper, HeteEdgeWalk, a solution method that does not involve meta-paths, is proposed. We design a dynamically adjusted bidirectional edge-sampling walk strategy. Specifically, edge sampling and the storage of recently selected edge types are used to better sample the network structure in a more balanced and comprehensive way. Finally, node classification and clustering experiments are performed on four real HINs with in-depth analysis. The results show a maximum performance improvement of 2% in node classification and at least 0.6% in clustering compared to baselines. This demonstrates the superiority of the method to effectively capture semantic information from HINs.

14.
Opt Express ; 30(10): 17140-17155, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-36221543

RESUMO

In addition to requirements on increasing transmission distance and bitrate, the study of underwater wireless optical communication (UWOC) is also facing limitations and challenges, such as interference induced by background noise, demand of higher receiver sensitivity, and communication security issues. In this paper, we experimentally demonstrate a physical layer secure and noise-resistant UWOC system based on spectrum spread and encrypted orthogonal frequency division multiplexing (SSE-OFDM) modulation, transmission through a 14.2 m sediment circulating water tank. Firstly, experimental results show that the required optical power ratio of signal and noise light (OPR) for QPSK signal under BER threshold of 3.8×10-3 is around -5.77 dB for a spectrum spread factor (N) of 100, with a signal-to-noise ratio (SNR) improvement of 19.06 dB. Secondly, without the background noise interference, the receiver sensitivity is also improved from -50 dBm to -62.4 dBm by using the SSE-OFDM modulation, achieving a maximum attenuation length (AL) of 19.67. Thirdly, physical layer security of UWOC can also be realized, which suppresses the SNR of eavesdropper to -3.72 dB while improving SNR of the authorized receiver to 17.56 dB under the condition of no leakage of keys. Additionally, analytical expressions for SSE-OFDM based UWOC performance are also derived, which agree well with the experimental results. Based on the analytical expressions, the maximum secrecy capacity Cs for SSE-OFDM based UWOC system under eavesdropping can be obtained by optimizing the intentionally inserted artificial noise power ratio and the spectrum spread factor N.

15.
FASEB J ; 35(6): e21612, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33948996

RESUMO

Lipid overload is intimately connected with the change of endothelial epigenetic status which impacts cellular signaling activities and endothelial function. Activating transcription factor 4 (ATF4) is involved in the regulation of lipid metabolism and meanwhile an epigenetic modifier. However, the role of ATF4 in the angiogenesis under lipid overload is not well understood. Here, to induce lipid overload status, we employed high-fat diet (HFD)-induced obese mouse model in vivo and palmitic acid (PA) to stimulate endothelial cells in vitro. Compared with mice fed with normal chow diet (NCD), HFD-induced obese mice showed angiogenic defects evidenced by decline in (1) blood flow recovery after hind limb ischemia, (2) wound healing speed after skin injury, (3) capillary density in injured tissues and matrigel plugs, and (4) endothelial sprouts of aortic ring. ATF4 deficiency aggravated above angiogenic defects in mice while ATF4 overexpression improved the blunted angiogenic response. Mechanistically, lipid overload lowered the H3K4 methylation levels at the regulatory regions of NOS3 and ERK1 genes, leading to reduced angiogenic signaling activity. Methionine adenosyltransferase 2A (MAT2A) is identified as a target of ATF4 and formed complex with ATF4 to direct lysine methyltransferase 2A (MLL1) to the regulatory regions of both genes for the maintenance of the H3K4 methylation level and angiogenic signaling activity. Here, we uncovered a novel metabolic-epigenetic coupling orchestrated by the ATF4-MAT2A axis for angiogenesis. The ATF4-MAT2A axis links lipid overload milieu to altered epigenetic status of relevant angiogenic signaling in endothelial cells, suggesting a potential therapeutic target for angiogenesis impaired by lipid overload.


Assuntos
Fator 4 Ativador da Transcrição/fisiologia , Epigênese Genética , Isquemia/patologia , Lipídeos/efeitos adversos , Metionina Adenosiltransferase/metabolismo , Neovascularização Patológica/patologia , Obesidade/complicações , Animais , Dieta Hiperlipídica , Isquemia/etiologia , Isquemia/metabolismo , Masculino , Metionina Adenosiltransferase/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Obesos , Neovascularização Patológica/etiologia , Neovascularização Patológica/metabolismo
16.
J Cell Mol Med ; 25(7): 3182-3193, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33611830

RESUMO

MARCH5 is a critical regulator of mitochondrial dynamics, apoptosis and mitophagy. However, its role in cardiovascular system remains poorly understood. This study aimed to investigate the role of MARCH5 in endothelial cell (ECs) injury and the involvement of the Akt/eNOS signalling pathway in this process. Rat models of myocardial infarction (MI) and human cardiac microvascular endothelial cells (HCMECs) exposed to hypoxia (1% O2 ) were used in this study. MARCH5 expression was significantly reduced in ECs of MI hearts and ECs exposed to hypoxia. Hypoxia inhibited the proliferation, migration and tube formation of ECs, and these effects were aggravated by knockdown of MARCH5 but antagonized by overexpressed MARCH5. Overexpression of MARCH5 increased nitric oxide (NO) content, p-eNOS and p-Akt, while MARCH5 knockdown exerted the opposite effects. The protective effects mediated by MARCH5 overexpression on ECs could be inhibited by eNOS inhibitor L-NAME and Akt inhibitor LY294002. In conclusion, these results indicated that MARCH5 acts as a protective factor in ischaemia/hypoxia-induced ECs injury partially through Akt/eNOS pathway.


Assuntos
Células Endoteliais/metabolismo , Proteínas de Membrana/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Transdução de Sinais , Ubiquitina-Proteína Ligases/metabolismo , Animais , Células Cultivadas , Cromonas/farmacologia , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Humanos , Masculino , Proteínas de Membrana/genética , Morfolinas/farmacologia , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Óxido Nítrico Sintase Tipo III/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Ubiquitina-Proteína Ligases/genética
17.
J Exp Bot ; 72(15): 5656-5672, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-33999128

RESUMO

The phytohormones ethylene and jasmonate play important roles in the adaptation of rice plants to salt stress. However, the molecular interactions between ethylene and jasmonate on rice seminal root growth under salt stress are unknown. In this study, the effects of NaCl on the homeostasis of ethylene and jasmonate, and on rice seminal root growth were investigated. Our results indicate that NaCl treatment promotes ethylene biosynthesis by up-regulating the expression of ethylene biosynthesis genes, whereas NaCl-induced ethylene does not inhibit rice seminal root growth directly, but rather indirectly, by promoting jasmonate biosynthesis. NaCl treatment also promotes jasmonate biosynthesis through an ethylene-independent pathway. Moreover, NaCl-induced jasmonate reduces meristem cell number and cell division activity via down-regulated expression of Oryza sativa PLETHORA (OsPLT) and cell division-related genes, respectively. Additionally, NaCl-induced jasmonate inhibits seminal root cell elongation by down-regulating the expression of cell elongation-related genes. Overall, salt stress promotes jasmonate biosynthesis through ethylene-dependent and -independent pathways in rice seminal roots, and jasmonate inhibits rice seminal root growth by inhibiting root meristem cell proliferation and root cell elongation.


Assuntos
Oryza , Ciclopentanos , Etilenos , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oxilipinas , Raízes de Plantas
18.
BMC Endocr Disord ; 21(1): 217, 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34715828

RESUMO

BACKGROUND: Pituitary carcinomas (PCs), defined as distant metastases of pituitary neoplasms, are very rare malignancies. Because the clinical presentation of PCs is variable, early diagnosis and management remain challenging. PCs are always refractory to comprehensive treatments, and patients with PCs have extremely poor prognoses. CASE PRESENTATION: We describe one case of a prolactin-secreting pituitary adenoma (PA) refractory to conventional therapy that evolved into a PC with intraspinal metastasis. A 34-year-old female was diagnosed with an invasive prolactin-secreting PA in 2009 and was unresponsive to medical treatment with bromocriptine. The tumor was gross totally removed via transsphenoidal surgery (TSS). However, the patient experienced multiple tumor recurrences or regrowth despite comprehensive treatments, including medical therapy, two gamma knife radiosurgeries (GKSs), and four frontal craniotomies. In 2016, she was found to have an intradural extramedullary mass at the level of the fourth lumbar vertebra. The intraspinal lesion was completely resected and was confirmed as a metastatic PC based on histomorphology and immunohistochemical staining. The literature on the diagnosis, molecular pathogenesis, treatment, and prognosis of patients with prolactin-secreting PCs was reviewed. CONCLUSION: PCs are very rare neoplasms with variable clinical features and poor prognosis. Most PCs usually arise from aggressive PAs refractory to conventional therapy. There is no reliable marker to identify aggressive PAs with a risk for progression to PCs; thus, it is difficult to diagnose these PCs early until the presence of metastatic lesions. It is still very challenging to manage patients with PCs due to a lack of standardized protocols for diagnosis and treatment. Establishing molecular biomarkers and the pathobiology of PCs could help in the early identification of aggressive PAs most likely to evolve into PCs.


Assuntos
Carcinoma/terapia , Antagonistas de Hormônios/uso terapêutico , Recidiva Local de Neoplasia/terapia , Neoplasias Hipofisárias/terapia , Prolactinoma/terapia , Neoplasias da Medula Espinal/terapia , Adulto , Bromocriptina/uso terapêutico , Carcinoma/secundário , Craniotomia , Progressão da Doença , Feminino , Humanos , Procedimentos Neurocirúrgicos , Neoplasias Hipofisárias/patologia , Prolactinoma/patologia , Radiocirurgia , Reoperação , Neoplasias da Medula Espinal/secundário
19.
BMC Ophthalmol ; 21(1): 61, 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33499815

RESUMO

BACKGROUND: This study analyzed the clinical features, imaging manifestations, histopathology, immunohistochemistry, and surgical approaches of the orbital solitary fibrous tumor (OSFT), as well as the factors for postoperative recurrence of such disease. METHODS: The clinical data of 16 patients with OSFT treated in our center from 2003 to 2020 were analyzed retrospectively, and the clinical symptoms, treatment methods, and follow-up results were recorded. RESULTS: Of the 16 patients, 8 were females (50.0 %) and 8 were males (50.0 %); the average age of treatment was 37 ± 7 years and the median follow-up time was 74 (8, 228) months. Sixteen patients with OSFT underwent a total of 29 operations, of which 12 were transorbital approach operations and 17 were transfronto-orbital approach operations. Ten patients (10/16, 62.5 %) had recurrence. The recurrence rate of transorbital approach operations was 83.3 % (10/12), and the recurrence rate of transfronto-orbital approach operations was 17.6 % (3/17). No patients had treatment-related complications. CONCLUSIONS: The main pathological feature of OSFT is a benign tumor. OSFT has a tendency to grow toward the cranio-orbital junction. The postoperative recurrence rate of OSFT is relatively high, so complete tumor resection is very important for prognosis. Inappropriate surgical approaches can lead to incomplete removal of the tumor and cause recurrence. Choosing the correct operation approach according to the position of the OSFT in the orbit and complete removal of the dura mater and bone affected by the tumor is crucial for the prognosis. Nevertheless, regular long-term follow-up after complete resection is necessary.


Assuntos
Neoplasias Orbitárias , Tumores Fibrosos Solitários , Adulto , China/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Orbitárias/cirurgia , Estudos Retrospectivos , Tumores Fibrosos Solitários/cirurgia , Centros de Atenção Terciária
20.
AAPS PharmSciTech ; 22(3): 108, 2021 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-33718989

RESUMO

The combination of self-microemulsifying drug delivery system (SMEDDS) and mesoporous silica materials favors the oral delivery of poorly water-soluble drugs (PWSD). However, the influence of the surface property of the mesopores towards the drug release and in vivo pharmacokinetics is still unknown. In this study, SBA-15 with hydroxyl groups (SBA-15-H), methyl groups (SBA-15-M), amino groups (SBA-15-A), or carboxyl groups (SBA-15-C) was combined with SMEDDS containing sirolimus (SRL). The diffusion and self-emulsifying of SMEDDS greatly improved the drug release over the raw SRL and SRL-SBA-15-R (R referred to as the functional groups). Results of drug absorption and X-ray photoelectron spectroscopy (XPS) showed strong hydrogen binding between SRL and the amino groups of SBA-15-A, which hindered the drug release and oral bioavailability of SRL-SMEDDS-SBA-15-A. The favorable release of SRL-SMEDDS-SBA-15-C (91.31 ± 0.57%) and SRL-SMEDDS-SBA-15-M (91.76 ± 3.72%) contributed to enhancing the maximum blood concentration (Cmax) and the area under the concentration-time curve (AUC0→48). In conclusion, the release of SRL-SMEDDS-SBA-15-R was determined by the surface affinity of the SBA-15-R and the interaction between the SRL molecules and the surface of SBA-15-R. This study suggested that the SMEDDS-SBA-15 was a favorable carrier for PWSD, and the surface property of the mesopores should be considered for the optimization of the SMEDDS-SBA-15.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos/fisiologia , Absorção Intestinal/fisiologia , Sirolimo/administração & dosagem , Sirolimo/farmacocinética , Administração Oral , Animais , Antibacterianos/administração & dosagem , Antibacterianos/química , Antibacterianos/farmacocinética , Disponibilidade Biológica , Cães , Emulsões/administração & dosagem , Emulsões/química , Emulsões/farmacocinética , Absorção Intestinal/efeitos dos fármacos , Masculino , Dióxido de Silício/administração & dosagem , Dióxido de Silício/química , Dióxido de Silício/farmacocinética , Sirolimo/química , Solubilidade , Propriedades de Superfície
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