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1.
Sensors (Basel) ; 24(6)2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38544071

RESUMO

The micro-deformation monitoring radar is usually based on Permanent Scatterer (PS) technology to realize deformation inversion. When the region is continuously monitored for a long time, the radar image amplitude and pixel variance will change significantly with time. Therefore, it is difficult to select phase-stable scatterers by conventional amplitude deviation methods, as they can seriously affect the accuracy of deformation inversion. For different regions studied within the same scenario, using a PS selection method based on the same threshold often increases the size of the deformation error. Therefore, this paper proposes a new PS selection method based on the Gaussian Mixture Model (GMM). Firstly, PS candidates (PSCs) are selected based on the pixels' amplitude information. Then, the amplitude deviation index of each PSC is calculated, and each pixel's probability values in different Gaussian distributions are acquired through iterations. Subsequently, the cluster types of pixels with larger probability values are designated as low-amplitude deviation pixels. Finally, the coherence coefficient and phase stability of low-amplitude deviation pixels are calculated. By comparing the probability values of each of the pixels in different Gaussian distributions, the cluster type with the larger probability, such as high-coherence pixels and high-phase stability pixels, is selected and designated as the final PS. Our analysis of the measured data revealed that the proposed method not only increased the number of PSs in the group, but also improved the stability of the number of PSs between groups.

2.
Int J Mol Sci ; 25(2)2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38256092

RESUMO

Secondary development is a key biological characteristic of woody plants and the basis of wood formation. Exogenous nitrogen can affect the secondary growth of poplar, and some regulatory mechanisms have been found in the secondary xylem. However, the effect of nitrogen on cambium has not been reported. Herein, we investigated the effects of different nitrogen concentrations on cambium development using combined transcriptome and metabolome analysis. The results show that, compared with 1 mM NH4NO3 (M), the layers of hybrid poplar cambium cells decreased under the 0.15 mM NH4NO3 (L) and 0.3 mM NH4NO3 (LM) treatments. However, there was no difference in the layers of hybrid poplar cambium cells under the 3 mM NH4NO3 (HM) and 5 mM NH4NO3 (H) treatments. Totals of 2365, 824, 649 and 398 DEGs were identified in the M versus (vs.) L, M vs. LM, M vs. HM and M vs. H groups, respectively. Expression profile analysis of the DEGs showed that exogenous nitrogen affected the gene expression involved in plant hormone signal transduction, phenylpropanoid biosynthesis, the starch and sucrose metabolism pathway and the ubiquitin-mediated proteolysis pathway. In M vs. L, M vs. LM, M vs. HM and M vs. H, differential metabolites were enriched in flavonoids, lignans, coumarins and saccharides. The combined analysis of the transcriptome and metabolome showed that some genes and metabolites in plant hormone signal transduction, phenylpropanoid biosynthesis and starch and sucrose metabolism pathways may be involved in nitrogen regulation in cambium development, whose functions need to be verified. In this study, from the point of view that nitrogen influences cambium development to regulate wood formation, the network analysis of the transcriptome and metabolomics of cambium under different nitrogen supply levels was studied for the first time, revealing the potential regulatory and metabolic mechanisms involved in this process and providing new insights into the effects of nitrogen on wood development.


Assuntos
Câmbio , Populus , Câmbio/genética , Reguladores de Crescimento de Plantas , Transcriptoma , Metaboloma , Nitrogênio , Populus/genética , Amido , Sacarose
3.
J Cell Mol Med ; 27(21): 3235-3246, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37635348

RESUMO

Liver fibrosis is a chronic inflammatory process characterized by the accumulation of extracellular matrix (ECM), which contributes to cirrhosis and hepatocellular carcinoma. Increasing evidence suggests that the activation of hepatic stellate cells (HSCs) under an inflammatory state leads to the secretion of collagens, which can cause cirrhosis. In this study, we analysed data from the Gene Expression Omnibus (GEO) databases to identify differentially expressed genes (DEGs) between quiescent and fibrotic HSCs. We found that Microfibril Associated Protein 2 (MFAP2) was elevated in carbon tetrachloride (CCl4)-induced liver fibrosis and Transforming Growth Factor-Beta 1 (TGF-ß1)-activated HSCs. Knockdown of MFAP2 inhibited HSC proliferation and partially attenuated TGF-ß-stimulated fibrogenesis markers. Bioinformatics analysis revealed that Fibrillin-1 (FBN1) was correlated with MFAP2, and the expression of FBN1 was significantly upregulated after MFAP2 overexpression. Silencing MFAP2 partially attenuated the activation of HSCs by inhibiting HSC proliferation and decreasing collagen deposits. In vitro results showed that the inhibition of MFAP2 alleviated hepatic fibrosis by inhibiting the activation and inducing the apoptosis of active HSCs in a CCl4-induced mouse model. In conclusion, our results suggest that MFAP2 is a potential target for the clinical treatment of liver fibrosis.


Assuntos
Microfibrilas , Fator de Crescimento Transformador beta , Animais , Camundongos , Tetracloreto de Carbono/toxicidade , Fibrilina-1/genética , Fibrilina-1/metabolismo , Células Estreladas do Fígado/metabolismo , Fígado/metabolismo , Cirrose Hepática/metabolismo , Microfibrilas/metabolismo , Microfibrilas/patologia , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
4.
Catheter Cardiovasc Interv ; 102(1): 36-45, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37172214

RESUMO

BACKGROUND: The combination of coronary imaging assessment and blood flow perturbation estimation has the potential to improve percutaneous coronary intervention (PCI) guidance. OBJECTIVES: We aimed to evaluate a novel method for fast computation of Murray law-based quantitative flow ratio (µQFR) from coregistered optical coherence tomography (OCT) and angiography (OCT-modulated µQFR, OCT-µQFR) in predicting physiological efficacy of PCI. METHODS: Patients treated by OCT-guided PCI in the OCT-arm of the Fractional Flow Reserve versus Optical Coherence Tomography to Guide RevasculariZAtion of Intermediate Coronary Stenoses trial (FORZA, NCT01824030) were included. Based on angiography and OCT before PCI, simulated residual OCT-µQFR was computed by assuming full stent expansion to the intended-to-treat segment. Plaque composition was automatically characterized using a validated artificial intelligence algorithm. Actual post-PCI OCT-µQFR pullback was computed based on coregistration of angiography and OCT acquired immediately after PCI. Suboptimal functional stenting result was defined as OCT-µQFR ≤ 0.90. RESULTS: Paired simulated residual OCT-µQFR and actual post-PCI OCT-µQFR were obtained in 76 vessels from 74 patients. Simulated residual OCT-µQFR showed good correlation (r = 0.80, p < 0.001), agreement (mean difference = -0.02 ± 0.02, p < 0.001), and diagnostic concordance (79%, 95% confidence interval: 70%-88%) with actual post-PCI OCT-µQFR. Actual post-PCI in-stent OCT-µQFR had a median value of 0.02 and was associated with left anterior descending artery lesion location (ß = 0.38, p < 0.001), higher baseline total plaque burden (ß = 0.25, p = 0.031), and fibrous plaque volume (ß = 0.24, p = 0.026). CONCLUSIONS: This study based on patients enrolled in a prospective OCT-guidance PCI trial shows that simulated residual OCT-µQFR had good correlation, agreement, and diagnostic concordance with actual post-PCI OCT-µQFR. In OCT-guided procedures, OCT-µQFR in-stent pressure drop was low and was significantly predicted by pre-PCI vessel/plaque characteristics.


Assuntos
Doença da Artéria Coronariana , Reserva Fracionada de Fluxo Miocárdico , Intervenção Coronária Percutânea , Humanos , Inteligência Artificial , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Vasos Coronários , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Valor Preditivo dos Testes , Estudos Prospectivos , Tomografia de Coerência Óptica/métodos , Resultado do Tratamento
5.
BMC Endocr Disord ; 23(1): 21, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36691016

RESUMO

BACKGROUND: To evaluate the endocrine hormone and metabolic indices in postmenopausal women with euthyroid and mild subclinical hypothyroidism after menopause hormone therapy (MHT). METHODS: A retrospective study of 587 postmenopausal women receiving MHT was conducted. Median (25-75th percentile) age was 52 (49-54) years. According to thyroid stimulating hormone (TSH) levels at initial diagnosis, the patients were divided into three groups: I (euthyroid with low normal TSH range, n = 460), II (euthyroid with upper normal TSH range, n = 106) and III (mild subclinical hypothyroidism, n = 21). After a continuous oral MHT regimen using the same estradiol potency for 6-18 month cycles, serum endocrine hormone and metabolic indices were reassessed. RESULTS: Compared with baseline, serum TSH levels in groups I and II significantly changed but all values were within the normal range. No significant difference was observed in serum TSH levels in group III. After treatment, all serum free tri-iodothyronine and free thyroxine levels were within the normal range. Serum total cholesterol, triglyceride, fasting plasma glucose, fasting insulin levels and homeostasis model assessment of insulin resistance index had significantly decreased in group I. There were no significant differences in all observed lipid and glucose parameters in group III, before and after treatment. CONCLUSION: MHT did not affect thyroid function in postmenopausal women with euthyroid and mild subclinical hypothyroidism. MHT led to an improvement in lipid and glucose indicators in euthyroid women with low normal TSH range.


Assuntos
Hipotireoidismo , Tireotropina , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Pós-Menopausa , Hipotireoidismo/tratamento farmacológico , Triglicerídeos , Glucose , Terapia de Reposição Hormonal , Tiroxina
6.
BMC Public Health ; 23(1): 916, 2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-37208621

RESUMO

BACKGROUND: Uterine fibroids are the most common benign neoplasm of the uterus and a major source of morbidity for women. We report an overview of trends in uterine fibroids of incidence rate, prevalence rate, years lived with disability (YLDs) rate in 204 countries and territories over the past 30 years and associations with age, period, and birth cohort. METHODS: The incident case, incidence rate, age-standardized rate (ASR) for incidence, prevalent case, prevalence rate, ASR for prevalence, number of YLDs, YLD rate, and ASR for YLDs were derived from the Global Burden of Disease 2019 (GBD 2019) study. We utilized an age-period-cohort (APC) model to estimate overall annual percentage changes in the rate of incidence, prevalence, and YLDs (net drifts), annual percentage changes from 10 to 14 years to 65-69 years (local drifts), period and cohort relative risks (period/cohort effects) between 1990 and 2019. RESULTS: Globally, the incident cases, prevalent cases, and the number of YLDs of uterine fibroids increased from 1990 to 2019 with the growth of 67.07%, 78.82% and 77.34%, respectively. High Socio-demographic Index (SDI) and high-middle SDI quintiles with decreasing trends (net drift < 0.0%), and increasing trends (net drift > 0.0%) were observed in middle SDI, low-middle SDI, and low SDI quintiles in annual percentage change of incidence rate, prevalence rate and YLDs rate over the past 30 years. There were 186 countries and territories that showed an increasing trend in incidence rate, 183 showed an increasing trend in prevalence rate and 174 showed an increasing trend in YLDs rate. Moreover, the effects of age on uterine fibroids increased with age and peaked at 35-44 years and then declined with advancing age. Both the period and cohort effects on uterine fibroids showed increasing trend in middle SDI, low-middle SDI and low SDI quintiles in recent 15 years and birth cohort later than 1965. CONCLUSIONS: The global burden of uterine fibroids is becoming more serious in middle SDI, low-middle SDI and low SDI quintiles. Raising awareness of uterine fibroids, increasing medical investment and improving levels of medical care are necessary to reduce future burden.


Assuntos
Carga Global da Doença , Leiomioma , Humanos , Feminino , Incidência , Prevalência , Anos de Vida Ajustados por Deficiência , Leiomioma/epidemiologia , Estudos de Coortes , Saúde Global , Anos de Vida Ajustados por Qualidade de Vida
7.
Ecotoxicol Environ Saf ; 259: 115031, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37210998

RESUMO

PURPOSE: To determine the influence of the environmental endocrine disruptor bisphenol A (BPA) on germ cell cyst breakdown and explore the possible mechanisms regulating this activity. METHODS: BPA (2 µg/kg/d or 20 µg/kg/d) or tocopherol-stripped corn oil (vehicle control) was administered to pregnant mice by gavage at gestational day 11, and the offspring (prenatally treated mice) were sacrificed and ovariectomized at postnatal day (PND) 4 and PND22. Ovarian morphology was documented in the first filial (F1) generation female offspring, and the follicles were analyzed and classified morphologically on PND 4. To discover differentially expressed genes and associated target pathways, we used RNA-seq, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and Gene Ontology (GO) analysis. The mRNA expression of key steroid hormone synthesis-related genes was evaluated by Q-PCR in forskolin-induced KGN cells. Western blotting (WB) and qRTPCR were used to determine the protein and gene expression levels of brain-derived neurotrophic factor (BDNF). RESULTS: BPA, a typical endocrine disrupting chemical (EDC), decreased the expression of the key steroid hormone synthesis-related genes P450scc and aromatase, while the expression of Star increased significantly and caused no significant difference in the expression of Cyp17a1 or HSD3ß in forskolin-induced KGN cells. Moreover, we confirmed that in utero exposure to environmentally relevant concentrations of BPA (2 µg/kg/d and 20 µg/kg/d) could significantly disrupt germ cell cyst breakdown, leading to the generation of fewer primordial follicles than in the control group. The factors mediating the inhibitory effects included the PI3K-Akt signaling pathway and a significant downregulation of BDNF. CONCLUSIONS: These findings indicate that in utero exposure to BPA at low doses, which are lower than recommended as 'safe' dosages, may influence the formation of primordial follicles by inhibiting the expression of steroid hormone synthesis-related genes and partly by regulating the BDNF-mediated PI3K/Akt pathway.


Assuntos
Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Gravidez , Animais , Camundongos , Feminino , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Colforsina/farmacologia , Transdução de Sinais , Compostos Benzidrílicos/toxicidade , Células Germinativas , Esteroides , Hormônios
8.
Int J Phytoremediation ; 25(4): 524-537, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35790485

RESUMO

A hydroponic method was conducted to test whether Spathiphyllum kochii is tolerant to multiple HMs as well as to evaluate whether sodium silicate promotes plant growth and alleviates HM stress mainly by assessing biomass, HM accumulation characteristics and antioxidant enzyme activities (AEAs). Three soil extractions from an uncontaminated soil, a comparable lightly HM-contaminated soil (EnSE), and a comparable heavily HM-contaminated soil (ExSE) with or without 1 mM sodium silicate supplementation were used. S. kochii showed no obvious symptoms when cultured in EnSE and ExSE, indicating that it was a multi-HM-tolerant species. The biomass and photosynthesis followed the order: UnSE > EnSE > ExSE, but the opposite order was found for HM concentration, AEAs, and malondialdehyde content. Silicate had no effects on the growth and HM bioaccumulation characteristics of S. kochii cultured in UnSE but exhibited a novel role in decreasing HM uptake by 13.61-41.51% in EnSE and ExSE, respectively, corresponding upregulated AEAs, and reduced malondialdehyde contents, resulting in increased biomass and alleviating HM stress. The activities of peroxidase and superoxide dismutase were upregulated by an increase in soil extraction HM concentration and further upregulated by silicate supplementation, indicating that they were important mechanisms alleviating HM stress in S. kochii.


Phytoremediation is an economical and environmentally friendly technology for the alleviation of heavy metal (HM)-contaminated soil. Improving bioremediation efficiency is crucial for this kind of technology. Many studies have shown that silicon plays a novel role in plant growth and adversity responses, but studies in the field of phytoremediation are limited. In addition, phytoremediation plant species are usually hyperaccumulators or may be tolerant crops, commercial crops, or wild species from mining areas, and the use of landscape species in phytoremediation is limited. This is the first report on the effects of silicate on the multi-HM bioaccumulation characteristics of a garden plant (Spathiphyllum kochii) cultured in uncontaminated and HM-contaminated soil extractions. This study will broaden phytoremediation species screening and enrich our understanding of the mechanisms by which Si supports the bioremediation of HM-contaminated environments.HIGHLIGHTSS. kochii was a multi-heavy metal-tolerant species.Silicon played a novel role in reducing heavy metal concentrations by 14­40% and 14­42% in shoots and roots, respectively.Silicon upregulated antioxidant enzyme activities to alleviate heavy metal stress in plants.


Assuntos
Metais Pesados , Poluentes do Solo , Metais Pesados/análise , Solo , Biodegradação Ambiental , Poluentes do Solo/análise , Silicatos , Suplementos Nutricionais
9.
Int J Mol Sci ; 24(24)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38139109

RESUMO

Exogenous nitrogen and carbon can affect plant cell walls, which are composed of structural carbon. Sucrose synthase (SUS), invertase (INV), hexokinase (HXK), phosphoglucomutase (PGM), and UDP-glucose pyrophosphorylase (UGP) are the key enzymes of sucrose metabolism involved in cell wall synthesis. To understand whether these genes are regulated by carbon and nitrogen to participate in structural carbon biosynthesis, we performed genome-wide identification, analyzed their expression patterns under different carbon and nitrogen treatments, and conducted preliminary functional verification. Different concentrations of nitrogen and carbon were applied to poplar (Populus trichocarpa Torr. and Gray), which caused changes in cellulose, lignin, and hemicellulose contents. In poplar, 6 SUSs, 20 INVs, 6 HXKs, 4 PGMs, and 2 UGPs were identified. Moreover, the physicochemical properties, collinearity, and tissue specificity were analyzed. The correlation analysis showed that the expression levels of PtrSUS3/5, PtrNINV1/2/3/5/12, PtrCWINV3, PtrVINV2, PtrHXK5/6, PtrPGM1/2, and PtrUGP1 were positively correlated with the cellulose content. Meanwhile, the knockout of PtrNINV12 significantly reduced the cellulose content. This study could lay the foundation for revealing the functions of SUSs, INVs, HXKs, PGMs, and UGPs, which affected structural carbon synthesis regulated by nitrogen and carbon, proving that PtrNINV12 is involved in cell wall synthesis.


Assuntos
Populus , Populus/metabolismo , Celulose/metabolismo , Lignina/metabolismo , Carbono/metabolismo , Nitrogênio/metabolismo , Regulação da Expressão Gênica de Plantas
10.
Int J Mol Sci ; 24(19)2023 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-37834448

RESUMO

The WRKY transcription factor (TF) family is one the largest plant-specific transcription factor families. It has been proven to play significant roles in multiple plant biological processes, especially stress response. Although many WRKY TFs have been identified in various plant species, WRKYs in white birch (Betula platyphylla Suk.) remain to be studied. Here, we identified a total of 68 BpWRKYs, which could be classified into four main groups. The basic physiochemical properties of these TFs were analyzed using bioinformatics tools, including molecular weight, isoelectric point, chromosome location, and predicted subcellular localization. Most BpWRKYs were predicted to be located in the nucleus. Synteny analysis found 17 syntenic gene pairs among BpWRKYs and 52 syntenic gene pairs between BpWRKYs and AtWRKYs. The cis-acting elements in the promoters of BpWRKYs could be enriched in multiple plant biological processes, including stress response, hormone response, growth and development, and binding sites. Tissue-specific expression analysis using qRT-PCR showed that most BpWRKYs exhibited highest expression levels in the root. After ABA, salt (NaCl), or cold treatment, different BpWRKYs showed different expression patterns at different treatment times. Furthermore, the results of the Y2H assay proved the interaction between BpWRKY17 and a cold-responsive TF, BpCBF7. By transient expression assay, BpWRKY17 and BpWRKY67 were localized in the nucleus, consistent with the previous prediction. Our study hopes to shed light for research on WRKY TFs and plant stress response.


Assuntos
Proteínas de Plantas , Fatores de Transcrição , Fatores de Transcrição/metabolismo , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Betula/genética , Betula/metabolismo , Regulação da Expressão Gênica de Plantas , Filogenia
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