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1.
Plant Physiol ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38850036

RESUMO

Water transportation to developing tissues relies on the structure and function of plant xylem cells. Plant microtubules govern the direction of cellulose microfibrils and guide secondary cell wall formation and morphogenesis. However, the relevance of microtubule-determined xylem wall thickening patterns in plant hydraulic conductivity remains unclear. In the present study, we identified a maize (Zea mays) semi-dominant mutant, designated drought-overly-sensitive1 (ZmDos1), the upper leaves of which wilted even when exposed to well-watered conditions during growth; the wilting phenotype was aggravated by increased temperatures and decreased humidity. Protoxylem vessels in the stem and leaves of the mutant showed altered thickening patterns of the secondary cell wall (from annular to spiral), decreased inner diameters, and limited water transport efficiency. The causal mutation for this phenotype was found to be a G-to-A mutation in the maize gene α-tubulin4, resulting in a single amino acid substitution at position 196 (E196K). Ectopic expression of the mutant α-tubulin4 in Arabidopsis (Arabidopsis thaliana) changed the orientation of microtubule arrays, suggesting a determinant role of this gene in microtubule assembly and secondary cell wall thickening. Our findings suggest that the spiral wall thickenings triggered by the α-tubulin mutation are stretched during organ elongation, causing a smaller inner diameter of the protoxylem vessels and affecting water transport in maize. This study underscores the importance of tubulin-mediated protoxylem wall thickening in regulating plant hydraulics, improves our understanding of the relationships between protoxylem structural features and functions, and offers candidate genes for the genetic enhancement of maize.

2.
J Exp Bot ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38655916

RESUMO

Endocytic recycling is an intracellular trafficking pathway that returns endocytosed molecules to the plasma membrane (PM) via the recycling endosome. This pathway plays a crucial role in remodeling PM composition and is thus essential for normal cellular homeostasis. In plants, endocytic recycling regulates the localization and abundance of receptors, transporters, and channels at the PM that are involved in many aspects of plant growth and development. Despite its importance, the recycling endosome and the underlying sorting mechanisms for cargo recycling in plants remain understudied in comparison to the endocytic recycling pathways of animal systems. In this review, we focus on the cumulative evidence suggesting the existence of endosomes decorated by regulators that contribute to recycling in plant cells. We summarize the chemical inhibitors used for analyzing cargo recycling and discuss recent advances in our understanding of how endocytic recycling participates in various plant cellular and physiological events.

3.
Development ; 147(13)2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-32541006

RESUMO

The interaction between the receptor-like kinase (RLK) FERONIA (FER) and the secreted peptide RAPID ALKALINIZATION FACTOR1 (RALF1) is vital for development and stress responses in Arabidopsis Ligand-induced membrane dynamics affect the function of several RLKs, but the effects of the RALF1-FER interaction on the dynamics of FER and the ensuing effects on its functionality are poorly understood. Here, we show that RALF1 modulated the dynamics and partitioning of FER-GFP at the plasma membrane (PM). Moreover, FER was internalized by both clathrin-mediated endocytosis (CME) and clathrin-independent endocytosis (CIE) under steady-state conditions. After RALF1 treatment, FER-GFP internalization was primarily enhanced via the CME pathway, raising FER-GFP levels in the vacuole. RALF1 treatment also modulated trafficking of other PM proteins, such as PIN2-GFP and BRI1-GFP, increasing their vacuolar levels by enhancing their internalization. Importantly, blocking CME attenuated RALF1-mediated root growth inhibition independently of RALF1-induced early signaling, suggesting that the RALF1 can also exert its effects via the CME pathway. These findings reveal that the RALF1-FER interaction modulates plant growth and development, and this might also involve endocytosis of PM proteins.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Endocitose/fisiologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Hormônios Peptídicos/metabolismo , Fosforilação/genética , Fosforilação/fisiologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
4.
Plant J ; 108(2): 426-440, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34343378

RESUMO

The plant hormone auxin controls many aspects of plant development. Membrane trafficking processes, such as secretion, endocytosis and recycling, regulate the polar localization of auxin transporters in order to establish an auxin concentration gradient. Here, we investigate the function of the Arabidopsis thaliana R-SNAREs VESICLE-ASSOCIATED MEMBRANE PROTEIN 721 (VAMP721) and VAMP722 in the post-Golgi trafficking required for proper auxin distribution and seedling growth. We show that multiple growth phenotypes, such as cotyledon development, vein patterning and lateral root growth, were defective in the double homozygous vamp721 vamp722 mutant. Abnormal auxin distribution and root patterning were also observed in the mutant seedlings. Fluorescence imaging revealed that three auxin transporters, PIN-FORMED 1 (PIN1), PIN2 and AUXIN RESISTANT 1 (AUX1), aberrantly accumulate within the cytoplasm of the double mutant, impairing the polar localization at the plasma membrane (PM). Analysis of intracellular trafficking demonstrated the involvement of VAMP721 and VAMP722 in the endocytosis of FM4-64 and the secretion and recycling of the PIN2 transporter protein to the PM, but not its trafficking to the vacuole. Furthermore, vamp721 vamp722 mutant roots display enlarged trans-Golgi network (TGN) structures, as indicated by the subcellular localization of a variety of marker proteins and the ultrastructure observed using transmission electron microscopy. Thus, our results suggest that the R-SNAREs VAMP721 and VAMP722 mediate the post-Golgi trafficking of auxin transporters to the PM from the TGN subdomains, substantially contributing to plant growth.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Ácidos Indolacéticos/metabolismo , Proteínas R-SNARE/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Transporte Biológico , Brefeldina A/farmacologia , Membrana Celular/metabolismo , Recuperação de Fluorescência Após Fotodegradação , Complexo de Golgi/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Mutação , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas , Proteínas R-SNARE/genética
5.
Am J Physiol Endocrinol Metab ; 323(1): E2-E7, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35635329

RESUMO

Insulin, a principal anabolic hormone produced by pancreatic ß-cells, has a primary function of storage of nutrients following excessive energy intake. Pre- or early type 2 diabetes stages present hyperinsulinemia (ß-cell dysfunction) and insulin resistance. Initiation of hyperinsulinemia is triggered by a loss of first-phase glucose-stimulated insulin secretion with altered membrane ion channel distribution. More factors, including insulin resistance and excessive proliferation of ß-cells, deteriorate the hyperinsulinemia, whereas the hyperinsulinemia contributes to further development of insulin resistance and type 2 diabetes; to develop eventually late-stage diabetes with absolute insulin deficiency. In this mini-review, the major focus was put on the causes and pathophysiology of hyperinsulinemia, and the metabolic consequences and current treatment of hyperinsulinemia were discussed. The data used in this narrative review were collected mainly from relevant discoveries in the past 3 years.


Assuntos
Diabetes Mellitus Tipo 2 , Hiperinsulinismo , Resistência à Insulina , Glucose/metabolismo , Homeostase , Humanos , Insulina/metabolismo , Resistência à Insulina/fisiologia
6.
New Phytol ; 235(2): 518-532, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35358335

RESUMO

The plant receptor-like kinase FERONIA (FER) functions in the response to multiple extracellular signals, thereby regulating diverse cellular processes, such as polarized cell growth, hormone signaling and responses to pathogens. Here, we reported that in Arabidopsis thaliana, flagellin peptide flg22 stimulus significantly promoted the lateral mobility and dissociation of FER from the plasma membrane by inducing the association of FER with membrane microdomain components. FER underwent constitutive endocytosis and recycling in a brefeldin A (BFA)-sensitive manner via a clathrin-mediated pathway. Following flg22 elicitation, FER localized to bona fide endosomes via two distinct endocytic routes, showing differential sensitivity to BFA. These results at the single-particle level confirm that FER acts as an essential regulator during flg22 perception and immune activation, thus broadening our understanding of location-specific protein dynamics and membrane trafficking in receptor/receptor kinase signaling.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Brefeldina A/farmacologia , Endocitose , Flagelina/metabolismo , Flagelina/farmacologia , Fosfotransferases/metabolismo
7.
J Exp Bot ; 73(1): 68-77, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34610124

RESUMO

Membrane proteins have key functions in signal transduction, transport, and metabolism. Therefore, deciphering the interactions between membrane proteins provides crucial information on signal transduction and the spatiotemporal organization of protein complexes. However, detecting the interactions and behaviors of membrane proteins in their native environments remains difficult. Förster resonance energy transfer (FRET) is a powerful tool for quantifying the dynamic interactions and assembly of membrane proteins without disrupting their local environment, supplying nanometer-scale spatial information and nanosecond-scale temporal information. In this review, we briefly introduce the basic principles of FRET and assess the current state of progress in the development of new FRET techniques (such as FRET-FLIM, homo-FRET, and smFRET) for the analysis of plant membrane proteins. We also describe the various FRET-based biosensors used to quantify the homeostasis of signaling molecules and the active state of kinases. Furthermore, we summarize recent applications of these advanced FRET sensors in probing membrane protein interactions, stoichiometry, and protein clustering, which have shed light on the complex biological functions of membrane proteins in living plant cells.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Proteínas de Membrana , Fenômenos Biofísicos , Homeostase , Proteínas de Membrana/genética , Transdução de Sinais
8.
Plant Cell ; 31(12): 3015-3032, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31597687

RESUMO

Plant phospholipase Ds (PLDs), essential regulators of phospholipid signaling, function in multiple signal transduction cascades; however, the mechanisms regulating PLDs in response to pathogens remain unclear. Here, we found that Arabidopsis (Arabidopsis thaliana) PLDδ accumulated in cells at the entry sites of the barley powdery mildew fungus, Blumeria graminis f. sp hordei Using fluorescence recovery after photobleaching and single-molecule analysis, we observed higher PLDδ density in the plasma membrane after chitin treatment; PLDδ also underwent rapid exocytosis. Fluorescence resonance energy transfer with fluorescence lifetime imaging microscopy showed that the interaction between PLDδ and the microdomain marker AtREMORIN1.3 (AtREM1.3) increased in response to chitin, indicating that exocytosis facilitates rapid, efficient sorting of PLDδ into microdomains upon pathogen stimulus. We further unveiled a trade-off between brefeldin A (BFA)-resistant and -sensitive pathways in secretion of PLDδ under diverse conditions. Upon pathogen attack, PLDδ secretion involved syntaxin-associated VAMP721/722-mediated exocytosis sensitive to BFA. Analysis of phosphatidic acid (PA), hydrogen peroxide, and jasmonic acid (JA) levels and expression of related genes indicated that the relocalization of PLDδ is crucial for its activation to produce PA and initiate reactive oxygen species and JA signaling pathways. Together, our findings revealed that the translocation of PLDδ to papillae is modulated by exocytosis, thus triggering PA-mediated signaling in plant innate immunity.plantcell;31/12/3015/FX1F1fx1.


Assuntos
Arabidopsis/imunologia , Membrana Celular/metabolismo , Imunidade Inata , Fosfolipase D/metabolismo , Doenças das Plantas/imunologia , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/microbiologia , Proteínas de Arabidopsis/metabolismo , Ascomicetos/patogenicidade , Brefeldina A/imunologia , Brefeldina A/metabolismo , Quitina/imunologia , Quitina/metabolismo , Ciclopentanos/metabolismo , Exocitose/efeitos dos fármacos , Exocitose/imunologia , Peróxido de Hidrogênio/metabolismo , Imunidade Inata/efeitos dos fármacos , Oxilipinas/metabolismo , Ácidos Fosfatídicos/metabolismo , Fosfolipase D/genética , Doenças das Plantas/microbiologia , Proteínas Qa-SNARE/metabolismo , Proteínas R-SNARE/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas SNARE/genética , Proteínas SNARE/metabolismo , Transdução de Sinais/imunologia , Transdução de Sinais/fisiologia
9.
BMC Gastroenterol ; 22(1): 174, 2022 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35397495

RESUMO

BACKGROUND: Gastric glomus tumor (GGT) is a rare neoplasm that is difficult to distinguish from other gastric submucosal tumors due to a lack of diagnostic experience. The goal of this study was to better understand GGT by looking at its clinicopathological features, computed tomography (CT) features, and differential diagnosis. METHODS: The clinical data and CT findings of 21 pathologically confirmed GGT patients were examined. The clinical characteristics and CT findings of benign GGT were compared to gastric stromal tumors (GST) (n = 30) and heterotopic pancreas (n = 30). RESULTS: The 21 cases included six males and fifteen females ranging in age from 42 to 64 years. The lesions were found in the gastric body in four cases and the antrum in seventeen. GGT was diagnosed as benign in 20 cases and malignant in one. In benign cases, the glomus cells were small, uniform, showed perivascular hemangiopericytoma­like or solid nest­like structures. Obvious mitotic figures were observed in the malignant case. SMA staining was positive in the tumor cells. A quasi-round or round solid mass protruded into the gastric cavity in 20 benign cases, with a clear and smooth edge. The long to short diameter ratio was 1.01 ± 0.15. All of the benign cases had obvious enhancement, with homogeneous enhancement in ten cases and heterogeneous enhancement in ten cases, as well as central filling enhancement in 12 cases. The ratio of CT value of lesion to abdominal aorta in arterial phase and venous phase were (0.41 ± 0.11) and (0.81 ± 0.20), which were significantly higher than GST and heterotopic pancreas. The irregular mass broke through the gastric wall and invaded liver with poorly defined boundary and internal necrosis, heterogeneous persistent moderate enhancement with thickening blood supply arteries was seen in one malignant case with a long diameter of 150 mm and a thick diameter of 30 mm. CONCLUSIONS: CT enhancement usually shows persistent obvious enhancement, especially in arterial phase, which provides important value for the diagnosis. CT findings can help in the differential diagnosis of GGT and other submucosal tumors.


Assuntos
Tumor Glômico , Neoplasias Gástricas , Adulto , Diagnóstico Diferencial , Feminino , Tumor Glômico/diagnóstico por imagem , Tumor Glômico/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Estudos Retrospectivos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/patologia , Tomografia Computadorizada por Raios X/métodos
10.
Phytother Res ; 36(4): 1724-1735, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35174550

RESUMO

Our current research aims to evaluate the efficiency of a flavor enhancer, maltol (produced by heating ginseng) against cisplatin-evoked cardiotoxicity by establishing cisplatin-induced heart injury in vivo and H9C2 rat cardiomyocyte model. The cisplatin-treated mice at 3 mg/kg for four times on the 7th, 9th, 11th and 13th day, and in them appeared a serious cardiac damage accompanied with the increase in indicators of heart damage. Multiple exposure of 3 mg/kg for four times of cisplatin increased cardiac cells apoptosis with increased expression of Bax and cleaved-caspase 3, and decreased expression of Bcl-2. Interestingly, supplement of maltol at doses of 50 and 100 mg/kg for 15 days significantly suppressed the cardiac disturbance. In cultured H9C2 cells, maltol enhanced PI3K/Akt expression level during cisplatin treatment, and reduced cisplatin-induced apoptosis. Notably, inhibition of PI3K/Akt by LY294002 and HY-10249A lessened the efficacy of maltol. In mice, maltol apparently induced PI3K/Akt in heart tissues and protected against cisplatin-induced cardiotoxicity. In conclusion, maltol exerted the protective effects against cisplatin-induced cardiotoxicity, at least partially by inhibiting the activation of PI3K/Akt signaling pathways in cardiomyocytes, to ease oxidative stress, and alleviate reactive oxygen species-mediated apoptosis.


Assuntos
Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Animais , Apoptose , Cardiotoxicidade/tratamento farmacológico , Cisplatino/efeitos adversos , Camundongos , Miócitos Cardíacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pironas , Ratos , Roedores/metabolismo , Transdução de Sinais
11.
Genomics ; 113(1 Pt 2): 1176-1188, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33276006

RESUMO

Thymic involution is a sign of immunosenescence, but little is known about it in goose. miRNAs and lncRNAs are critical factors regulating organ growth and development. In this study, we comprehensively analyzed the profiles of lncRNAs, miRNAs and mRNAs during the development and involution of the thymus in Magang goose. The results showed that 2436 genes, 16 miRNAs and 417 lncRNAs were differentially co-expressed between the developmental (20-embryo age, 3-day post-hatch and 3-month age) and degenerative (6-month age) stages. The functional analysis showed that these differentially expressed genes were significantly enriched in cell proliferation, cell adhesion, apoptotic signaling pathway, and Notch signaling pathway. In addition, we established a gene-gene network through the STRING database and identified 50 key genes. Finally, we constructed a miRNA-mRNA network followed by a lncRNA-miRNA-mRNA network. These results suggest that lncRNAs and miRNAs may be involved in the regulation of thymic development and involution in goose.


Assuntos
Gansos/genética , Redes Reguladoras de Genes , Transcriptoma , Animais , Gansos/crescimento & desenvolvimento , Gansos/imunologia , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Timo/crescimento & desenvolvimento , Timo/metabolismo
12.
New Phytol ; 224(4): 1479-1489, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31230354

RESUMO

Vesicle exocytosis and endocytosis control the activities and turnover of plasma membrane proteins required for signaling triggering or attenuating at the cell surface. In recent years, the diverse exocytic and endocytic trafficking pathways have been uncovered in plants. The balance between conventional and unconventional protein secretion provides an efficient strategy to respond to stress conditions. Similarly, clathrin-dependent and -independent endocytosis cooperatively regulate the dynamics of membrane proteins in response to environmental cues. In fact, many aspects of plant growth and development, such as tip growth, immune response, and protein polarity establishment, involve the tight deployment of exo-endocytic trafficking. However, our understanding of their intersection is limited. Here, we discuss recent advances in the molecular factors coupling plant exo-endocytic trafficking and the biological significance of balance between exocytosis and endocytosis in plants.


Assuntos
Endocitose/fisiologia , Células Vegetais/metabolismo , Plantas/metabolismo , Citoesqueleto de Actina/metabolismo , Exocitose , Interações Hospedeiro-Patógeno , Proteínas de Membrana/metabolismo , Redes e Vias Metabólicas , Microtúbulos/metabolismo , Proteínas SNARE/metabolismo , Sinaptotagminas/metabolismo
13.
J Appl Toxicol ; 36(11): 1460-7, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26923100

RESUMO

Methamphetamine (METH), an illicit drug, is widely abused in many parts of the world. Mounting evidence shows that METH exposure contributes to neurotoxicity, particularly for the monoaminergic neurons. However, to date, only a few studies have tried to unravel the mechanisms involved in METH-induced non-monoaminergic neural damage. Therefore, in the present study, we tried to explore the mechanisms for METH-induced neural damage in cortical neurons. Our results showed that METH significantly increased intracellular [Ca(2) (+) ]i in Ca(2) (+) -containing solution rather than Ca(2) (+) -free solution. Moreover, METH also upregulated calmodulin (CaM) expression and activated CaM-dependent protein kinase II (CaMKII). Significantly, METH-induced neural damage can be partially retarded by CaM antagonist W7 as well as CaMKII blocker KN93. In addition, L-type Ca(2) (+) channel was also proved to be involved in METH-induced cell damage, as nifedipine, the L-type Ca(2) (+) channel-specific inhibitor, markedly attenuated METH-induced neural damage. Collectively, our results suggest that Ca(2) (+) -CaM-CaMKII is involved in METH-mediated neurotoxicity, and it might suggest a potential target for the development of therapeutic strategies for METH abuse. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Estimulantes do Sistema Nervoso Central/toxicidade , Metanfetamina/toxicidade , Neurônios/efeitos dos fármacos , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Neurônios/enzimologia , Neurônios/patologia , Ratos Sprague-Dawley
14.
Zhonghua Yi Xue Za Zhi ; 96(5): 329-33, 2016 Feb 02.
Artigo em Zh | MEDLINE | ID: mdl-26875709

RESUMO

OBJECTIVE: To qualitatively and quantitatively compare MSI images and WB images derived from spectral CT imaging with CU images in accessing gastric carcinoma. METHODS: The clinical data and imaging findings of 91 cases of gastric carcinomas between December 2013 and May 2015 were analyzed retrospectively. All patients underwent CU CT and enhanced CT with spectral imaging in AP and VP. MSI images were reconstructed based on monochromatic images of 70 keV in AP. WB images were obtained by water-iodine pair substance isolation of the AP images. Two abdominal radiologists independently evaluated the image quality and the depiction of gastric carcinoma in CU, MSI and WB images using a 5-point scale. The sensitivities of gastric cancer were evaluated by using enhanced images as the reference standard.The CT number of various regions, image noise, relative enhancement CT value of tumors and metastasis were measured and calculated on CU and MSI images. The CNR of gastric tumor were measured on CU, MSI and WB images. Effective radiation doses for triple-phase and dual-phase scan were calculated. Differences were tested for statistical significance using the Wilcoxon's signed rank test and the paired t-test. RESULTS: Interobserver agreement with regard to image quality and the depiction of gastric carcinoma was good(all kappa>0.70). There was no statistical significant difference in image quality between CU(4.30±0.63) and MSI(4.17±0.58) images(P>0.05), both higher than WB(3.87±0.84) images (both P<0.01). The depiction of gastric carcinoma in CU(3.86±0.50) and MSI(3.73±0.55) images had no statistical significant difference (P>0.05), and both higher than WB(3.34±0.38) images( both P<0.01). The sensitivities of CU, MSI and WB images were 91.2%, 95.6%, 93.4%. The CT number of gastric tumors, liver metastasis and aorta, image noise on MSI images were slightly higher than on TNE images(P<0.05). The CT number of gastric tumors, liver metastasis and aorta, image noise on MSI images were slightly higher than on TNE images(P<0.05). The CT number of lymph nodes, liver and muscle, CT relative enhancement value of gastric tumors, lymph nodes and liver metastasis had no significant difference between TNE and MSI images (all P>0.05). The CNR of gastric tumors had significant difference between groups: WB images were higher than MSI and MSI were higher than CU images(all P<0.01). The dose saving by removing the CU was 8.2 mSv(32%). CONCLUSION: The MSI images derived from spectral CT can provide comparable image quality to CU images and reliable diagnostic information for gastric tumors, which is superior to WB images, replacing CU images will lower radiation exposure by 32%.


Assuntos
Neoplasias Gástricas , Tomografia Computadorizada por Raios X , Estudos de Viabilidade , Humanos , Linfonodos , Estudos Retrospectivos
15.
BMC Complement Altern Med ; 15: 103, 2015 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-25886561

RESUMO

BACKGROUND: Primary insomnia is a common health issue in the modern world. We conducted a systematic review of the auricular therapy, aiming to evaluate whether there are advantages of auricular acupuncture with seed or pellet attachments for the treatment of primary insomnia. METHODS: A search of relevant literatures was performed on major medical databases, including Medline, Embase, CENTRAL, CBM, CNKI, VIP, Wanfang Data and so on. Risk of bias evaluation, meta-analysis, sensitivity analysis and evidence rating of all extracted information were conducted also. RESULTS: A total of 1381 records were identified, with 15 studies deemed eligible for the present review. Meta-analyses were conducted in two comparisons separately: participants received auricular acupuncture were more likely to make an improvement in clinical effective rate (RR = 1.40, 95% CI 1.07 to 1.83), sleep duration (MD = 56.46, 95% CI 45.61 to 67.31), sleep efficiency(MD = 12.86, 95% CI 9.67 to 16.06), global score on PSQI (MD = -3.41, 95% CI -3.93 to -2.89), number of awakenings( MD = -3.27, 95% CI -6.30 to -0.25) and sleep onset latency(MD = -10.35, 95% CI -14.37 to -6.33) when compared to sham auricular acupuncture or placebo; while in auricular acupuncture VS medications comparison, a better effective rate (RR = 1.24, 95% CI 1.15 to 1.34), better sleep efficiency(MD = 21.44, 95% CI 16.30 to 26.58), lower PSQI score (MD = -3.62, 95% CI -4.59 to -2.65) and less adverse effect (RR = 0.11, 95% CI 0.04 to 0.26) can be seen also in auricular acupuncture group. Although these results suggested benefits of auricular acupuncture, the overall quality of evidence rated by the GRADE system was low. CONCLUSION: Statistical analyses of the outcomes revealed a positive effect of auricular acupuncture for primary insomnia. Nonetheless, considering the poor methodological quality, insufficient sample size and possible publication bias, current evidence is not yet adequate to provide a strong support for the use of auricular acupuncture in the treatment of primary insomnia. More strictly designed clinical studies will be needed to obtain a more explicit conclusion.


Assuntos
Acupuntura Auricular/métodos , Distúrbios do Início e da Manutenção do Sono/terapia , Sono , Implantes de Medicamento , Humanos , Sementes
16.
Zhonghua Yi Xue Za Zhi ; 95(24): 1947-50, 2015 Jun 23.
Artigo em Zh | MEDLINE | ID: mdl-26710701

RESUMO

OBJECTIVE: To explore the computed tomography (CT) features and pathological correlations of primitive neuroectodermal tumor (PNET) of the kidney. METHODS: The CT features of 5 cases of pathologically confirmed PNETs were retrospectively reviewed along with a literature review to analyze the CT features and pathological correlations. RESULTS: The age range was 19-78 years. CT image showed solitary mass of heterogeneous density with ill-defined margins. One case had multifocal necrosis. Among 3 cases of cystic changes, there were mural nodule (n = 2) and patchy calcification (n = 1). Four cases showed invasive growth into renal cortex and pelvis with cortical interruption (n = 3) and destruction of renal capsule and invasion into perirenal fat space (n = 1). The tumors were confined to kidney contour with enlarged kidney (n = 3). All 5 cases showed slight heterogenous enhancement in cortico-medullary phase with persistent moderate enhancement (n = 4) and persistent mild enhancement (n = 1) in nephrographic phase. CONCLUSION: Renal PNET is common in young patients with a high degree of malignancy. CT features include large mass with heterogenous density and poor-defined border confined within renal contour. Necrosis and cystic changes occur commonly with invasive growth. Persistent enhancement is found during nephrographic phase. A definite diagnosis is dependent upon pathological and immunohistochemical examinations.


Assuntos
Tomografia Computadorizada por Raios X , Humanos , Rim , Neoplasias Renais , Imageamento por Ressonância Magnética , Tumores Neuroectodérmicos Primitivos , Pelve , Exame Físico , Estudos Retrospectivos
17.
Int J Biol Macromol ; 262(Pt 2): 129971, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38354933

RESUMO

Soil drought and salinization, caused by water deficiency, have become the greatest concerns limiting crop production. Up to now, the WRKY transcription factor and histone deacetylase have been shown to be involved in drought and salt responses. However, the molecular mechanism underlying their interaction remains unclear in cotton. Herein, we identified GhWRKY4, a member of WRKY gene family, which is induced by drought and salt stress and is located in the nucleus. The ectopic expression of GhWRKY4 in Arabidopsis enhanced drought and salt tolerance, and suppressing GhWRKY4 in cotton increased susceptibility to drought and salinity. Subsequently, DAP-seq analysis revealed that the W box element in the promoter of stress-induced genes could potentially be the binding target for GhWRKY4 protein. GhWRKY4 binds to the promoters of GhHDA8 and GhNHX7 via W box element, and the expression level of GhHDA8 was increased in GhWRKY4-silenced plants. In addition, GhHDA8-overexpressed Arabidopsis were found to be hypersensitive to drought and salt stress, while silencing of GhHDA8 enhanced drought and salt tolerance in cotton. The stress-related genes, such as GhDREB2A, GhRD22, GhP5CS, and GhNHX7, were induced in GhHDA8-silenced plants. Our findings indicate that the GhWRKY4-GhHDA8 module regulates drought and salt tolerance in cotton. Collectively, the results provide new insights into the coordination of transcription factors and histone deacetylases in regulating drought and salt stress responses in plants.


Assuntos
Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Gossypium/metabolismo , Tolerância ao Sal/genética , Secas , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Plantas Geneticamente Modificadas/genética , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
18.
Environ Sci Pollut Res Int ; 30(35): 84631-84644, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37368214

RESUMO

Shipping companies' implementation of sustainable shipping management is an important means of protecting major water bodies in the marine environment. This research establishes a theoretical model based on institutional theory and incorporates a micro-consciousness level to explore the factors influencing companies' implementation of sustainable shipping practices. After surveying the management of Chinese shipping companies, a total of 282 datasets were obtained for analysis. This study demonstrated that rules and regulations, societal norms, environmental awareness, and legal awareness can improve shipping companies' sustainable shipping practices. Meanwhile, these practices have a positive impact on the environmental, financial, and competitive performance of shipping companies. Moreover, these findings are highly significant for maritime environmental protection and sustainability.


Assuntos
Conservação dos Recursos Naturais , Corporações Profissionais , Navios , Desenvolvimento Sustentável , Meios de Transporte , Modelos Teóricos , Indústrias , Meios de Transporte/métodos , Conservação dos Recursos Hídricos , China
19.
Front Oncol ; 13: 1225180, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37664013

RESUMO

Background: Limited studies have observed the prognostic value of CT images for esophageal neuroendocrine carcinoma (NEC) due to rare incidence and low treatment experience in clinical. In this study, the pretreatment enhanced CT texture features and clinical characteristics were investigated to predict the overall survival of esophageal NEC. Methods: This retrospective study included 89 patients with esophageal NEC. The training and testing cohorts comprised 61 (70%) and 28 (30%) patients, respectively. A total of 402 radiomics features were extracted from the tumor region that segmented pretreatment venous phase CT images. The least absolute shrinkage and selection operator (LASSO) Cox regression was applied to feature dimension reduction, feature selection, and radiomics signature construction. A radiomics nomogram was constructed based on the radiomics signature and clinical risk factors using a multivariable Cox proportional regression. The performance of the nomogram for the pretreatment prediction of overall survival (OS) was evaluated for discrimination and calibration. Results: Only the enhancement degree was an independent factor in clinical variable influenced OS. The radiomics signatures demonstrated good predictability for prognostic status discrimination. The radiomics nomogram integrating texture signatures was slightly superior to the nomogram derived from the combined model with a C-index of 0.844 (95%CI: 0.783-0.905) and 0.847 (95% CI: 0.782-0.912) in the training set, and 0.805 (95%CI: 0.707-0.903) and 0.745 (95% CI: 0.639-0.851) in the testing set, respectively. Conclusion: The radiomics nomogram based on pretreatment CT radiomics signature had better prognostic power and predictability of the overall survival in patients with esophageal NEC than the model using combined variables.

20.
BMJ Open ; 13(5): e068370, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37130664

RESUMO

OBJECTIVES: This study aimed to screen the potential risk factors for academic burnout among adolescents during the COVID-19 pandemic, develop and validate a predictive tool based on the risk factors for predicting academic burnout. DESIGN: This article presents a cross-sectional study. SETTING: This study surveyed two high schools in Anhui Province, China. PARTICIPANTS: A total of 1472 adolescents were enrolled in this study. OUTCOME MEASURES: The questionnaires included demographic characteristic variables, living and learning states and adolescents' academic burnout scale. Least absolute shrinkage and selection operator and multivariate logistic regression analyses were employed to screen the risk factors for academic burnout and develop a predictive model. The receiver operating characteristic (ROC) curve and decision curve analysis (DCA) were used to assess the accuracy and discrimination of the nomogram. RESULTS: In this study, 21.70% of adolescents reported academic burnout. Multivariable logistic regression analysis showed that single-child family (OR=1.742, 95% CI: 1.243 to 2.441, p=0.001), domestic violence (OR=1.694, 95% CI: 1.159 to 2.476, p=0.007), online entertainment (>8 hours/day, OR=3.058, 95% CI: 1.634 to 5.720, p<0.001), physical activity (<3 hours/week, OR=1.686, 95% CI: 1.032 to 2.754, p=0.037), sleep duration (<6 hours/night, OR=2.342, 95% CI: 1.315 to 4.170, p=0.004) and academic performance (<400 score, OR=2.180, 95% CI: 1.201 to 3.958, p=0.010) were independent significant risk factors associated with academic burnout. The area under the curve of ROC with the nomogram was 0.686 in the training set and 0.706 in the validation set. Furthermore, DCA demonstrated that the nomogram had good clinical utility for both sets. CONCLUSIONS: The developed nomogram was a useful predictive model for academic burnout among adolescents during the COVID-19 pandemic. It is essential to emphasise the importance of mental health and promote a healthy lifestyle among adolescents during the future pandemic.


Assuntos
Esgotamento Psicológico , COVID-19 , População do Leste Asiático , Nomogramas , Estudantes , Adolescente , Humanos , Esgotamento Psicológico/epidemiologia , COVID-19/epidemiologia , COVID-19/psicologia , Estudos Transversais , População do Leste Asiático/psicologia , População do Leste Asiático/estatística & dados numéricos , Pandemias , Estudantes/psicologia , Fatores de Risco , Medição de Risco
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