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1.
Plant J ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38872484

RESUMO

Acteoside is a bioactive phenylethanoid glycoside widely distributed throughout the plant kingdom. Because of its two catechol moieties, acteoside displays a variety of beneficial activities. The biosynthetic pathway of acteoside has been largely elucidated, but the assembly logic of two catechol moieties in acteoside remains unclear. Here, we identified a novel polyphenol oxidase OfPPO2 from Osmanthus fragrans, which could hydroxylate various monophenolic substrates, including tyrosine, tyrosol, tyramine, 4-hydroxyphenylacetaldehyde, salidroside, and osmanthuside A, leading to the formation of corresponding catechol-containing intermediates for acteoside biosynthesis. OfPPO2 could also convert osmanthuside B into acteoside, creating catechol moieties directly via post-modification of the acteoside skeleton. The reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis and subcellular localization assay further support the involvement of OfPPO2 in acteoside biosynthesis in planta. These findings suggest that the biosynthesis of acteoside in O. fragrans may follow "parallel routes" rather than the conventionally considered linear route. In support of this hypothesis, the glycosyltransferase OfUGT and the acyltransferase OfAT could direct the flux of diphenolic intermediates generated by OfPPO2 into acteoside. Significantly, OfPPO2 and its orthologs constitute a functionally conserved enzyme family that evolved independently from other known biosynthetic enzymes of acteoside, implying that the substrate promiscuity of this PPO family may offer acteoside-producing plants alternative ways to synthesize acteoside. Overall, this work expands our understanding of parallel pathways plants may employ to efficiently synthesize acteoside, a strategy that may contribute to plants' adaptation to environmental challenges.

2.
Int J Mol Sci ; 25(6)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38542323

RESUMO

As the global population ages, the number of patients with osteoporosis is rapidly rising. The existing first-line clinical drugs are bone resorption inhibitors that have difficulty restoring the bone mass of elderly patients to the safe range. The range and period of use of existing peptides and monoclonal antibodies are limited, and small-molecule bone formation-promoting drugs are urgently required. We established an I-9 synthesis route with high yield, simple operation, and low cost that was suitable for future large-scale production. I-9 administration promoted bone formation and increased bone mass in mice with low bone mass in an aged C57 mouse model. Our findings revealed a hitherto undescribed pathway involving the BMP2-ERK-ATF4 axis that promotes osteoblast differentiation; I-9 has favorable biosafety in mice. This study systematically investigated the efficacy, safety, and mechanism of I-9 for treating osteoporosis and positions this drug for preclinical research in the future. Thus, this study has promoted the development of small-molecule bone-promoting drugs.


Assuntos
Conservadores da Densidade Óssea , Osteoporose , Idoso , Camundongos , Humanos , Animais , Osteogênese , Preparações Farmacêuticas/metabolismo , Osteoporose/tratamento farmacológico , Osteoporose/metabolismo , Conservadores da Densidade Óssea/uso terapêutico , Peptídeos/metabolismo , Diferenciação Celular , Osteoblastos/metabolismo , Fator 4 Ativador da Transcrição/metabolismo , Proteína Morfogenética Óssea 2/metabolismo
3.
J Transl Med ; 21(1): 254, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-37046345

RESUMO

BACKGROUND: Metastasis, the leading cause of cancer-related death in patients diagnosed with ovarian cancer (OC), is a complex process that involves multiple biological effects. With the continuous development of sequencing technology, single-cell sequence has emerged as a promising strategy to understand the pathogenesis of ovarian cancer. METHODS: Through integrating 10 × single-cell data from 12 samples, we developed a single-cell map of primary and metastatic OC. By copy-number variations analysis, pseudotime analysis, enrichment analysis, and cell-cell communication analysis, we explored the heterogeneity among OC cells. We performed differential expression analysis and high dimensional weighted gene co-expression network analysis to identify the hub genes of C4. The effects of RAB13 on OC cell lines were validated in vitro. RESULTS: We discovered a cell subcluster, referred to as C4, that is closely associated with metastasis and poor prognosis in OC. This subcluster correlated with an epithelial-mesenchymal transition (EMT) and angiogenesis signature and RAB13 was identified as the key marker of it. Downregulation of RAB13 resulted in a reduction of OC cells migration and invasion. Additionally, we predicted several potential drugs that might inhibit RAB13. CONCLUSIONS: Our study has identified a cell subcluster that is closely linked to metastasis in OC, and we have also identified RAB13 as its hub gene that has great potential to become a new therapeutic target for OC.


Assuntos
Neoplasias Ovarianas , Transcriptoma , Humanos , Feminino , Transcriptoma/genética , Neoplasias Ovarianas/patologia , Movimento Celular/genética , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-37803213

RESUMO

Emerging evidence suggests an association between maternal hypertension during pregnancy and mental health in the offspring. However, less is known about the role of hypertensive pregnancy in behavioral symptoms and brain structures of the offspring as well as in their developmental changes. Here, we utilized neuroimaging and behavioral data from 11,878 participants aged 9-10 years and their 2-year follow-up from the Adolescent Brain Cognitive Development (ABCD) study to investigate the long-term effects of maternal hypertension during pregnancy on early adolescent behavior and brain anatomy. Specifically, adolescents born of mothers with maternal hypertension are at risk of long-lasting behavioral problems, as manifested by higher externalizing and internalizing behavior scores at both 9-10 years and 11-12 years. These participants additionally presented with a higher cortical thickness, particularly in the fronto-parieto-temporal areas at 9-10 years. Four regions, including the left parahippocampus, left lateral orbitofrontal lobe, right superior temporal lobe and right temporal pole, remained thicker 2 years later. These findings were partially validated in rats modeled with Nω-nitro-L-arginine methyl ester (L-NAME) preeclampsia. Therefore, clinicians and women who experience hypertension during pregnancy should be warned of this risk, and healthcare providers should recommend appropriate clinical interventions for pregnancy-induced hypertension.

5.
J Nat Prod ; 84(4): 972-978, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33667092

RESUMO

Two tocotrienol derivatives, garcipaucinones A (1) and B (2), and a biosynthetically related known analogue (3) were isolated from the fruit of Garcinia paucinervis. Their structures including absolute configurations were unequivocally determined by spectroscopic methods complemented with electronic circular dichroism (ECD) calculations and gauge-independent atomic orbital (GIAO) NMR calculations. Compounds 1 and 2 are the first naturally occurring tocotrienol derivatives with a 3,10-dioxatricyclo-[7.3.1.02,7]tridecane skeleton incorporating an unusual γ-pyrone motif. A reasonable biosynthetic pathway for formation of the two compounds is proposed. The antiproliferative and anti-inflammatory activities of compounds 1 and 2 were also evaluated.


Assuntos
Garcinia/química , Tocotrienóis/farmacologia , Animais , Anti-Inflamatórios , Antineoplásicos Fitogênicos , Linhagem Celular Tumoral , China , Frutas/química , Humanos , Camundongos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Células RAW 264.7 , Tocotrienóis/isolamento & purificação
6.
Int J Syst Evol Microbiol ; 70(1): 493-498, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31617846

RESUMO

A novel actinobacterial strain, designated NEAU-LL90T, was isolated from cow dung collected from Shangzhi, Heilongjiang Province, north-east PR China and characterized by using a polyphasic approach. Morphological and chemotaxonomic characteristics were consistent with those members of the genus Nocardia. The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannoside. The predominant menaquinone detected was MK-8(H4, ω-cycl). Major fatty acids (>10 %) were identified as C16:0, C18:1ω9c, C18:0 and 10-methyl C19:0. Mycolic acids were present. The results of 16S rRNA gene sequence analysis showed that strain NEAU-LL90T belongs to the genus Nocardia with high sequence similarity to Nocardia niigatensis JCM11894T (98.1 %), similarities to other type strains of species of the genus Nocardia were found to be lower than 98.0 %. Furthermore, a combination of DNA-DNA hybridization results and some phenotypic characteristics demonstrated that strain NEAU-LL90T could be distinguished from its closest relative. Therefore, it is proposed that strain NEAU-LL90T represents a novel species of the genus Nocardia, for which the name Nocardia stercoris sp. nov. is proposed. The type strain is NEAU-LL90T (=CGMCC 4.7500T=JCM 32663T).


Assuntos
Bovinos/microbiologia , Esterco/microbiologia , Nocardia/classificação , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Ácidos Micólicos/química , Nocardia/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Microbiologia do Solo , Vitamina K 2/análogos & derivados , Vitamina K 2/química
7.
Future Oncol ; 16(31): 2487-2498, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32746631

RESUMO

Aim: A nomogram was constructed to forecast the overall survival (OS) of patients with mycosis fungoides/Sezary syndrome. Patients & methods: The clinicopathological information of patients was obtained from the Surveillance, Epidemiology and End Results (SEER) database. A model was established based on the independent prognostic factors. Predictive ability of the model was evaluated with the concordance index and calibration curves. Risk stratification was conducted for patients with similar tumor node metastasis (TNM) stages. Results: The model included 1997 eligible patients and seven prognostic factors for OS. The concordance index of the nomogram was 0.84 in the training and external validation cohorts, which indicated good predictive ability of the model and reliability of the results. The high agreement between the model predictions and actual observations was identified by calibration curves, which demonstrated the prediction accuracy of the model. Risk stratification displayed significant differences for patients with similar TNM stages, which suggested that the OS of patients with similar TNM stages could be further distinguished. Conclusion: We established a reliable nomogram to predict the OS of patients with mycosis fungoides/Sezary syndrome, which highlighted the advantages of nomograms over the conventional TNM staging system and promoted the application of individualized therapeutic strategies.


Assuntos
Micose Fungoide/mortalidade , Síndrome de Sézary/mortalidade , Neoplasias Cutâneas/mortalidade , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Micose Fungoide/diagnóstico , Micose Fungoide/epidemiologia , Micose Fungoide/terapia , Estadiamento de Neoplasias , Nomogramas , Prognóstico , Programa de SEER , Síndrome de Sézary/diagnóstico , Síndrome de Sézary/epidemiologia , Síndrome de Sézary/terapia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/terapia , Análise de Sobrevida , Estados Unidos/epidemiologia
8.
Chem Biodivers ; 16(12): e1900471, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31612620

RESUMO

One natural p-terphenyl glycoside, gliocladinin C, and two furano-polyene derivatives, chaetominins A and B, were isolated from potato endophytic fungus Chaetomium subaffine. The absolute configurations of these compounds were elucidated by HR-ESI-MS, NMR, the DP4+ probabilities and electronic circular dichroism (ECD) spectra. Furthermore, gliocladinin C and chaetominin A showed cytotoxic activity against two selected human tumor cell lines (Hep-2 and HepG-2).


Assuntos
Antineoplásicos/química , Chaetomium/metabolismo , Compostos de Terfenil/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Chaetomium/química , Dicroísmo Circular , Humanos , Espectroscopia de Ressonância Magnética , Conformação Molecular , Compostos de Terfenil/farmacologia
9.
Int J Syst Evol Microbiol ; 68(10): 3327-3332, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30141768

RESUMO

A novel actinomycete, designated strain NEAU-DSCPA1-4-4T, was isolated from rhizosphere soil of wheat and characterized using a polyphasic approach. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that the organism should be assigned to the genus Streptomyces. The strain formed a monophyletic clade with its closest relatives, Streptomyces ghanaensis DSM 40746T (97.7 % 16S rRNA gene sequence similarity) and Streptomyces viridosporus DSM 40243T (97.6 %). Similarly, chemotaxonomic data, including major menaquinones, fatty acid compositions and polar lipid profile, also supported the placement of strain NEAU-DSCPA1-4-4T in the genus Streptomyces. However, DNA-DNA relatedness, physiological and biochemical data showed that strain NEAU-DSCPA1-4-4T could be distinguished from its closest relatives. Therefore, we propose that strain NEAU-DSCPA1-4-4T represents a novel species of the genus Streptomyces, for which the name Streptomycestriticisoli sp. nov. is proposed, with NEAU-DSCPA1-4-4T (=CCTCC AA 2017025T=DSM 105118T) as the type strain.


Assuntos
Filogenia , Rizosfera , Microbiologia do Solo , Streptomyces/classificação , Triticum/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Streptomyces/genética , Streptomyces/isolamento & purificação , Vitamina K 2/química
10.
Antonie Van Leeuwenhoek ; 111(11): 2079-2086, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29779147

RESUMO

Two Gram-stain positive, aerobic actinomycete strains, designated NEAU-JGR1T and NEAU-JGC41, were isolated from soil collected from Fairy Lake Botanical Garden in Shenzhen, Guangdong Province, south of China. The 16S rRNA gene sequences analysis showed that the two strains exhibited 99.5% 16S rRNA gene sequence similarity with each other and were closely related to Promicromonospora thailandica JCM 17130T (99.4, 99.3%) and Promicromonospora citrea DSM 43110T (99.2, 99.2%). Phylogenetic analysis based on the 16S rRNA gene sequences indicated that the two strains clustered together and formed a cluster with P. thailandica JCM 17130T and P. citrea DSM 43110T. Both strains were observed to contain MK-9(H4) and MK-9(H2) as predominant menaquinones. Their whole cell sugar profiles were found to main contained rhamnose, ribose, glucose and galactose. The phospholipid profile contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, glycophosphatidylinositol, phosphatidylinositol mannoside, an unidentified glycolipid and an unidentified phospholipid. The predominant cellular fatty acids for the two strains were identified as anteiso-C15:0, iso-C15:0 and anteiso-C17:0. The DNA-DNA hybridization value between strains NEAU-JGR1T and NEAU-JGC41 was 85.1 ± 0.3%, and the values between the two strains and their close phylogenetic relatives were well below 70%, supporting the conclusion that they represent a distinct genomic species. An array of phenotypic characteristics also differentiated the isolates from closely related species. On the basis of the genetic and phenotypic properties, strains NEAU-JGR1T and NEAU-JGC41 can be classified as representatives of a novel species of the genus Promicromonospora, for which the name Promicromonospora viridis sp. nov., is proposed. The type strain is NEAU-JGR1T (= DSM 105536T = CGMCC 4.7473T).


Assuntos
Actinobacteria/genética , Fosfolipídeos/metabolismo , Filogenia , RNA Ribossômico 16S/genética , Microbiologia do Solo
11.
Entropy (Basel) ; 20(9)2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33265800

RESUMO

Network virtualization can offer more flexibility and better manageability for next generation Internet. With the increasing deployments of virtual networks in military and commercial networks, a major challenge is to ensure virtual network survivability against hybrid multiple failures. In this paper, we study the problem of recovering virtual networks affected by hybrid multiple failures in substrate networks and provide an integer linear programming formulation to solve it. We propose a heuristic algorithm to tackle the complexity of the integer linear programming formulation, which includes a faulty virtual network reconfiguration ranking method based on weighted relative entropy, a hybrid multiple failures ranking algorithm, and a virtual node migration method based on weighted relative entropy. In the faulty virtual network reconfiguration ranking method based on weighted relative entropy and virtual node migration method based on weighted relative entropy, multiple ranking indicators are combined in a suitable way based on weighted relative entropy. In the hybrid multiple failures ranking algorithm, the virtual node and its connective virtual links are re-embedded, firstly. Evaluation results show that our heuristic method not only has the best acceptance ratio and normal operation ratio, but also achieves the highest long-term average revenue to cost ratio compared with other virtual network reconfiguration methods.

12.
Plants (Basel) ; 13(3)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38337959

RESUMO

Tea is a popular beverage with characteristic functional and flavor qualities, known to be rich in bioactive metabolites such as tea polyphenols and theanine. Recently, tea varieties with variations in leaf color have been widely used in agriculture production due to their potential advantages in terms of tea quality. Numerous studies have used genome, transcriptome, metabolome, proteome, and lipidome methods to uncover the causes of leaf color variations and investigate their impacts on the accumulation of crucial bioactive metabolites in tea plants. Through a comprehensive review of various omics investigations, we note that decreased expression levels of critical genes in the biosynthesis of chlorophyll and carotenoids, activated chlorophyll degradation, and an impaired photosynthetic chain function are related to the chlorina phenotype in tea plants. For purple-leaf tea, increased expression levels of late biosynthetic genes in the flavonoid synthesis pathway and anthocyanin transport genes are the major and common causes of purple coloration. We have also summarized the influence of leaf color variation on amino acid, polyphenol, and lipid contents and put forward possible causes of these metabolic changes. Finally, this review further proposes the research demands in this field in the future.

13.
ACS Chem Neurosci ; 15(8): 1669-1683, 2024 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-38575140

RESUMO

The cannabinoid receptor 1 (CB1) is famous as the target of Δ9-tetrahydrocannabinol (THC), which is the active ingredient of marijuana. Suppression of CB1 is frequently suggested as a drug target or gene therapy for many conditions (e.g., obesity, Parkinson's disease). However, brain networks affected by CB1 remain elusive, and unanticipated psychological effects in a clinical trial had dire consequences. To better understand the whole brain effects of CB1 suppression we performed in vivo imaging on mice under complete knockout of the gene for CB1 (cnr1-/-) and also under the CB1 inverse agonist rimonabant. We examined white matter structural changes and brain function (network activity and directional uniformity) in cnr1-/- mice. In cnr1-/- mice, white matter (in both sexes) and functional directional uniformity (in male mice) were altered across the brain but network activity was largely unaltered. Conversely, under rimonabant, functional directional uniformity was not altered but network activity was altered in cortical regions, primarily in networks known to be altered by THC (e.g., neocortex, hippocampal formation). However, rimonabant did not alter many brain regions found in both our cnr1-/- results and previous behavioral studies of cnr1-/- mice (e.g., thalamus, infralimbic area). This suggests that chronic loss of cnr1 is substantially different from short-term suppression, subtly rewiring the brain but largely maintaining the network activity. Our results help explain why pathological mutations in CB1 (e.g., chronic pain) do not always provide insight into the side effects of CB1 suppression (e.g., clinical depression), and thus urge more preclinical studies for any drugs that suppress CB1.


Assuntos
Agonismo Inverso de Drogas , Piperidinas , Feminino , Camundongos , Masculino , Animais , Rimonabanto/farmacologia , Piperidinas/farmacologia , Pirazóis/farmacologia , Camundongos Knockout , Encéfalo , Receptores de Canabinoides , Receptor CB1 de Canabinoide/genética , Dronabinol/farmacologia
14.
Biomed Pharmacother ; 170: 116018, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38113628

RESUMO

Hepatocellular carcinoma (HCC) is one of the most fatal solid malignancies worldwide. Evidence suggests that thrombin stimulates tumor progression via fibrin formation and platelet activation. Meanwhile, we also found a correlation between thrombin and HCC through bioinformatics analysis. Dabigatran is a selective, direct thrombin inhibitor that reversibly binds to thrombin. Dabigatran was used as the lead agent in this study, and 19 dabigatran derivatives were designed and synthesized based on docking mode. The thrombin-inhibitory activity of the derivative AX-2 was slightly better than that of dabigatran. BX-2, a prodrug of AX-2, showed a fairly strong inhibitory effect on thrombin-induced platelet aggregation, and effectively antagonized proliferation of HCC tumor cells induced by thrombin at the cellular level. Furthermore, BX-2 reduced tumor volume, weight, lung metastasis, and secondary tumor occurrence in nude mouse models. BX-2 combined with sorafenib increased sorafenib efficacy. This study lays the foundation for discovering new anti-HCC mechanism based on thrombin. BX-2 can be used as an anti-HCC drug lead for further research.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Camundongos , Animais , Dabigatrana/farmacologia , Dabigatrana/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Trombina/metabolismo , Sorafenibe/farmacologia , Neoplasias Hepáticas/tratamento farmacológico
15.
J Cancer ; 15(11): 3427-3440, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38817863

RESUMO

Purpose: Platinum-based chemotherapy is effective but limited by resistance in high-grade serous ovarian cancer (HGSOC). Single-cell RNA sequencing (scRNA-seq) can reveal tumour cell heterogeneity and subclonal differentiation. We aimed to analyze resistance mechanisms and potential targets in HGSOC using scRNA-seq. Methods: We performed 10× genomics scRNA-seq sequencing on tumour tissues from 3 platinum-sensitive and 3 platinum-resistant HGSOC patients. We analyzed cell subcluster communication networks and spatial distribution using cellchat. We performed RNA-seq analysis on TACSTD2, a representative resistance gene in the E0 subcluster, to explore its molecular mechanism. Results: Epithelial cells, characterized by distinct chemotherapy resistance traits and highest gene copy number variations, revealed a specific cisplatin-resistant cluster (E0) associated with poor prognosis. E0 exhibited malignant features related to resistance, fostering growth through communication with fibroblasts and endothelial cells. Spatially, E0 promoted fibroblasts to protect tumour cells and impede immune cells infiltration. Furthermore, TACSTD2 was identified as a representative gene of the E0 subcluster, elucidating its role in platinum resistance through the Rap1/PI3K/AKT pathway. Conclusions: Our study reveals a platinum-resistant epithelial cell subcluster E0 and its association with TACSTD2 in HGSOC, uncovers new insights and evidence for the platinum resistance mechanism, and provides new ideas and targets for the development of therapeutic strategies against TACSTD2+ epithelial cancer cells.

16.
Water Sci Technol ; 68(4): 821-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23985512

RESUMO

The objective of this study was to evaluate the performance of the FAO-AquaCrop model in winter wheat in the southern Loess Plateau of China. Multi-year field experimental data from 2004 and 2011 were used to calibrate and validate the model for simulating biomass, canopy cover (CC), soil water content, and grain yield under rainfed conditions. The model performance was evaluated using root mean square error (RMSE) and Willmott index of agreement (d) as criteria. The RMSE ranged from 0.16 to 0.38 t/ha for simulating aboveground biomass, 1.87 to 4.15% for CC, 0.50 to 1.44 t/ha for grain yield, and 5.70 to 22.56 mm for soil water content. The d ranged from 0.22 to 0.89, 0.25 to 0.43, 0.36 to 0.62 and 0.95 to 0.98 for aboveground biomass, CC, soil water content and grain yield, respectively. Generally, the model performed better for simulating CC and yield than biomass and soil water content. The results further indicated that AquaCrop is capable of simulating winter wheat yield under rainfed conditions. Further improvement may be needed to capture the variation of different management practices such as fertility and irrigation levels in this region.


Assuntos
Simulação por Computador , Modelos Teóricos , Triticum/crescimento & desenvolvimento , Água , Biomassa , China , Fenômenos Geológicos , Reprodutibilidade dos Testes , Solo/química , Fatores de Tempo
17.
IEEE Trans Med Imaging ; 42(4): 1197-1209, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36449589

RESUMO

Segmenting the fine structure of the mouse brain on magnetic resonance (MR) images is critical for delineating morphological regions, analyzing brain function, and understanding their relationships. Compared to a single MRI modality, multimodal MRI data provide complementary tissue features that can be exploited by deep learning models, resulting in better segmentation results. However, multimodal mouse brain MRI data is often lacking, making automatic segmentation of mouse brain fine structure a very challenging task. To address this issue, it is necessary to fuse multimodal MRI data to produce distinguished contrasts in different brain structures. Hence, we propose a novel disentangled and contrastive GAN-based framework, named MouseGAN++, to synthesize multiple MR modalities from single ones in a structure-preserving manner, thus improving the segmentation performance by imputing missing modalities and multi-modality fusion. Our results demonstrate that the translation performance of our method outperforms the state-of-the-art methods. Using the subsequently learned modality-invariant information as well as the modality-translated images, MouseGAN++ can segment fine brain structures with averaged dice coefficients of 90.0% (T2w) and 87.9% (T1w), respectively, achieving around +10% performance improvement compared to the state-of-the-art algorithms. Our results demonstrate that MouseGAN++, as a simultaneous image synthesis and segmentation method, can be used to fuse cross-modality information in an unpaired manner and yield more robust performance in the absence of multimodal data. We release our method as a mouse brain structural segmentation tool for free academic usage at https://github.com/yu02019.


Assuntos
Algoritmos , Imageamento por Ressonância Magnética , Animais , Camundongos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Neuroimagem
18.
IEEE J Biomed Health Inform ; 27(2): 1072-1083, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36446007

RESUMO

Accurate neonatal brain MRI segmentation is valuable for investigating brain growth patterns and tracking the progression of neurodevelopmental disorders. However, it is a challenging task to use intensity-based methods to segment neonatal brain structures because of small contrast differences between brain regions caused by the inherent myelination process. Although convolutional neural networks offer the potential to segment brain structures in an intensity-independent manner, they suffer from lack of in-plane long-range dependency which is essential for the segmentation. To solve this problem, we propose a novel Transformer-Weighted network (TW-Net) to incorporate in-plane long-range dependency information. TW-Net employs a conventional encoder-decoder architecture with a Transformer module in the middle. The Transformer module uses a rotate-and-flip layer to better calculate the similarity between two patches in a slice to leverage similar patterns of geometrical and texture features within brain structures. In addition, a deep supervision module and squeeze-and-excitation blocks are introduced to incorporate boundary information of brain structures. Compared with state-of-the-art deep learning algorithms, TW-Net outperforms these methods for multiple-label tasks in 2D and 2.5D configurations on two independent public datasets, demonstrating that TW-Net is a promising method for neonatal brain MRI segmentation.


Assuntos
Imageamento por Ressonância Magnética , Neuroimagem , Humanos , Recém-Nascido , Algoritmos , Encéfalo/diagnóstico por imagem , Fontes de Energia Elétrica , Processamento de Imagem Assistida por Computador
19.
J Med Chem ; 66(3): 1742-1760, 2023 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-36662031

RESUMO

Most patients with senile osteoporosis (SOP) are severely deficient in bone mass, and treatments using bone resorption inhibitors, such as bisphosphonates, have shown limited efficacy. Small-molecule osteogenesis-promoting drugs are required to improve the treatment for this disease. Previously, we demonstrated that a compound with a benzofuran-like structure promoted bone formation by upregulating BMP-2, and it exhibited a therapeutic effect in SAMP-6 mice, glucocorticoid-induced osteoporosis rats, and ovariectomized rats. In this study, aged C57 and SAMP-6 mice models were used to investigate the therapeutic and preventive effects of compound 125 on SOP. scRNA-seq analysis showed that BMP-2 upregulation is the mechanism through which 125 accelerates bone turnover and increases the proportion of osteoblasts. We evaluated the structure-activity relationship of the candidate drugs and found that the derivative I-9 showed significantly higher efficacy than 125 and teriparatide in the zebrafish osteoporosis model. This study provides a foundation for the development of SOP drugs.


Assuntos
Benzofuranos , Osteoporose , Ratos , Camundongos , Animais , Peixe-Zebra , Osteoporose/tratamento farmacológico , Osteoporose/prevenção & controle , Osteogênese , Osteoblastos , Benzofuranos/farmacologia , Benzofuranos/uso terapêutico , Benzofuranos/química , Relação Estrutura-Atividade
20.
IEEE Comput Graph Appl ; 42(3): 65-73, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35657837

RESUMO

The rapid development of high-performance computing systems has led to a rapid increase in the speed of flow field simulation calculations. However, large-scale simulation output data lead to storage bottlenecks and inefficient data analysis. In this work, we used in situ visualization to process the simulation analysis of large-scale flow fields. Combined with narrative visual analysis, we designed a large-scale ocean flow field eddy evolution analysis system based on in situ visualization. Our system can generate high-precision eddy streamline structures in real time and supports eddy statistical analysis and tracking analysis at different ocean regional scales. Through the case data analysis of ocean simulation, we demonstrated the efficiency and effectiveness of the system.

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