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1.
Plant Cell Environ ; 46(5): 1562-1581, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36695201

RESUMO

Low light stress seriously decreased wheat grain number through the formation of aborted spike during the reproductive period and induced new tiller regeneration to offset the loss of grain number. However, the mechanism by which plants coordinate spike aborted growth and the regeneration of new tillers remains unknown. To better understand this coordinated process, morphological, physiological and transcriptomic analyses were performed under low light stress at the young microspore stage. Our findings indicated that leaves exhausted most stored carbohydrates in 1 day of darkness. However, spike and uppermost internode (UI) were converted from sink to source, due to increased abscisic acid (ABA) content and decreased cytokinin content. During this process, genes encoding amylases, Sugars Will Eventually be Exported Transporters (SWEET) and sucrose transporters or sucrose carriers (SUT/SUC) were upregulated in spike and UI, which degraded starch into soluble sugars and loaded them into the phloem. Subsequently, soluble sugars were transported to tiller node (TN) where cytokinin and auxin content increased and ABA content decreased, followed by unloading into TN cells by upregulated cell wall invertase (CWINV) genes and highly expressed H+ /hexose symporter genes. Finally, expansin genes integrated the sugar pathway and hormone pathway, and regulate the formation of new tillers directly.


Assuntos
Carboidratos , Triticum , Triticum/fisiologia , Ácido Abscísico/metabolismo , Proteínas de Membrana Transportadoras/genética , Sacarose/metabolismo , Citocininas , Açúcares , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
Eur Radiol ; 28(11): 4561-4569, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29728818

RESUMO

OBJECTIVES: To present in vivo female pelvic autonomous innervation and the relationship between nerves and their related organs by three-dimensional (3D) reconstruction based on magnetic resonance imaging (MRI). METHODS: Thirty patients with cervical cancer who underwent pelvic MRI and agreed to undergo additional magnetic resonance neurography (MRN) sequences were enrolled in the present study. MRI images from the same patient were acquired using T2-weighted fat saturation (T2W FS) and 3D-STIR-SPACE sequences. Detailed two-dimensional (2D) segmentation and 3D reconstruction of pelvic autonomic nerves (PAN) were performed on the basis of the images of the two sequences using 3D reconstruction software. The 2D segmentation and 3D reconstruction of pelvic organs were based on T2W FS images. The consistency of the 3D models of pelvic autonomous innervation constructed from the two sequences were analysed and compared, the pelvic autonomous innervation was presented, and the relationship between nerves and their related organs was characterised. RESULTS: The 3D reconstructions of PAN were successfully obtained from 3D-STIR-SPACE and T2W FS sequences in 30 patients and showed high correspondence. T2W FS images also enabled 3D reconstructions of pelvic organs to visualise the 3D distribution of PAN and the positional relationships between nerves and their related organs. CONCLUSION: The pelvic autonomic nerves and their related organs can be reconstructed on the basis of MRI to present personalised 3D anatomical information and offer individualised guidance during nerve-sparing radical hysterectomy (NSRH). KEY POINTS: • Nerve-sparing radical hysterectomy is a developing trend in cervical cancer surgery • MRI allows reconstructions of pelvic autonomic nerves and their related organs • The 3D reconstructions provide detailed 3D anatomical information on nerves.


Assuntos
Vias Autônomas/diagnóstico por imagem , Histerectomia/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Neuronavegação/métodos , Pelve/inervação , Cirurgia Assistida por Computador/métodos , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/cirurgia
3.
Arch Gynecol Obstet ; 298(2): 433-441, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29948169

RESUMO

PURPOSE: To analyze the relationship between fetal head size and maternal pelvis size using magnetic resonance imaging (MRI) with a 3-D reconstruction technique. METHODS: A total of 301 nulliparous full-term Chinese pregnant women with cephalic presentation were enrolled and received MRI examinations before labor onset. Data were collected and imported into Mimics software to reconstruct the maternal pelvis and fetus. RESULTS: Of 301 pregnant women, 212 underwent vaginal delivery and 32 received cesarean section. The body mass index (BMI) was significantly different between the vaginal delivery group and the suspected cephalopelvic disproportion (CPD) group; the larger the BMI, the higher was the risk of CPD. The transverse diameter of the pelvic inlet and the posterior sagittal diameter of the midpelvis were significantly larger in the vaginal delivery group, compared with the suspected CPD group. Fetal weight > 3.5 kg could be used as a diagnostic indicator for CPD. CONCLUSIONS: BMI is a risk factor for CPD, and fetal weight < 3.5 kg is an important diagnostic indicator for natural delivery in Chinese pregnant women.


Assuntos
Pelvimetria/métodos , Adulto , Índice de Massa Corporal , Desproporção Cefalopélvica/diagnóstico por imagem , Cesárea , China , Parto Obstétrico/métodos , Feminino , Peso Fetal , Feto/diagnóstico por imagem , Cabeça/diagnóstico por imagem , Cabeça/embriologia , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Paridade , Pelve/diagnóstico por imagem , Gravidez , Fatores de Risco
4.
Plant Dis ; 101(6): 1022-1028, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30682936

RESUMO

Brown blight disease caused by Colletotrichum species is a common and serious foliar disease of tea (Camellia sinensis). Fungal isolates from several tea plantations causing typical brown blight symptoms were identified as belonging to the Colletotrichum acutatum species complex and the Colletotrichum gloeosporioides species complex based on morphological characteristics as well as DNA analysis of the internal transcribed spacer (ITS) and glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Colletotrichum acutatum, a new causal agent associated with C. sinensis, showed high phenotypic and genotypic diversity compared with the more commonly reported C. gloeosporioides. Phylogenetic analysis derived from individual and combined ITS and GAPDH sequences clearly clustered C. acutatum and C. gloeosporioides into separate species. Pathogenicity tests validated that both species were causal agents of tea brown blight disease and were highly pathogenic to tea leaves. However, the two groups of C. gloeosporioides with low levels of variability within their ITS and GAPDH regions differed in their virulence. This study reports for the first time the characterization of C. acutatum and C. gloeosporioides causing brown blight disease on tea (Camellia sinensis (L.) O. Kuntze) in China.

5.
Heliyon ; 10(1): e23749, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38226223

RESUMO

Background: Thyroid-associated ophthalmopathy (TAO) is an orbital disease closely related to thyroid disease with a long-lasting duration that can be blinding and disabling. Recently, structural and functional neuroimaging studies have been performed in TAO patients, but studies have reported inconsistent results. This quantitative meta-analysis was conducted to identify convergent patterns of abnormal brain function among different studies in TAO. Methods: We searched PubMed, EMBASE, Cochrane, and Web of Science, performed reference tracking, and retrieved 15 eligible studies. Peak coordinates were extracted from these studies and subsequently tested for convergence using activation likelihood estimation (ALE). Results: Compared to healthy subjects, resting-state brain activity in the whole brain of TAO patients was significantly increased in the left superior frontal gyrus (SFG) and decreased in the left cuneus/precuneus. Functional decoding analysis of the BrainMap database revealed that these regions are predominantly associated with cognitive and emotional impairment. In this study, task-related meta-analytic connectivity modeling (MACM) analysis was used to describe the connectivity and function of the two seed regions. Significant coactivation of these regions was found primarily in the bilateral superior parietal lobule, medial frontal gyrus, left fusiform gyrus, left cingulate gyrus, supplementary motor area and thalamus. Conclusion: Our findings underscore the role of the SFG and the cuneus/precuneus in the pathophysiology of TAO, highlighting the crucial impact of working memory deficits.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 274: 121033, 2022 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-35305520

RESUMO

In recent years, antibiotic residues in food have been of great concern to regulators and consumers. In this study, a novel fluorescent sensor based on S, N-doped carbon quantum dots (S, N-CQDs) was established for rapid detection of tetracycline antibiotics (TCs). Through the internal filter effect (IFE), QDs fluorescence can be effectively quenched by TCs, endowing it an "off" condition. Under the optimal conditions, the TC concentration in the range of 1.88-60 µmol/L had a good linear relationship with the change of QDs fluorescence intensity, and the limit of detection (LOD) was calculated as 0.56 µmol/L (S/N = 3). Furthermore, the proposed "Turn-off" sensor could be employed to quickly and accurately quantify TCs residues even in milk, honey and tap water. The recovery rate was as high as between 93.61% and 102.31%. The established sensor has great application value in the fields of food safety and drug analysis, and provides broad prospects for the future food industry.


Assuntos
Compostos Heterocíclicos , Pontos Quânticos , Antibacterianos , Carbono/química , Corantes Fluorescentes/química , Limite de Detecção , Pontos Quânticos/química , Espectrometria de Fluorescência , Tetraciclina
7.
Front Plant Sci ; 13: 967210, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36092403

RESUMO

Improving water use efficiency (WUE) has been proven to be a prosperous way to produce more grain in drought-prone areas. Transpiration efficiency (TE) has been proposed as a criterion for screening cultivars with high WUE. This study quantifies the relations of TE to relative soil water content (RSWC) gradients using pot experiments and evaluates the capability of the relations of TE-RSWC on assessing the cultivar performance in field yield and WUE. Twelve winter wheat cultivars were grown at 6 RSWC, 12.1, 24.2, 36.3, 48.4, 60.5, and 72.6% of field capacity (FC = 24.8 g/g) for 33 days in tightly sealed pots preventing soil evaporation. The results showed that TE decreased power functionally following the increase in RSWC for all cultivars. The relationship could be described as TE = TE FC × (RSWC) b , named TE-RSWC curve. This curve could be divided into an orderly area where the rank of cultivars was stable when RSWC ≤ 12.1% or RSWC ≥ 72.6% and a disorderly area where the rank was unstable when 12.1% < RSWC < 72.6%. To assess the consistency of pot TE to field yield and WUE, the same 12 varieties were grown under rainfed and two irrigations (75 mm at the jointing and flowering stages, respectively). TE FC was found to be positively related to field yield and WUE independent of irrigation. TE measured near the wilting point was negatively related to field yield and WUE. These results indicated that TE FC could be used as a surrogate for screening high-yield and high-WUE cultivars. The consistency and inconsistency can be attributed to the orderly area and disorderly area of the TE-RSWC curves.

8.
Front Neurol ; 13: 785040, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35370890

RESUMO

Objective: To investigate the effect of Fufang Huangqi Decoction on the gut microbiota in patients with class I or II myasthenia gravis (MG) and to explore the correlation between gut microbiota and MG (registration number, ChiCTR2100048367; registration website, http://www.chictr.org.cn/listbycreater.aspx; NCBI: SRP338707). Methods: In this study, microbial community composition and diversity analyses were carried out on fecal specimens from MG patients who did not take Fufang Huangqi Decoction (control group, n = 8) and those who took Fufang Huangqi Decoction and achieved remarkable alleviation of symptoms (medication group, n = 8). The abundance, diversity within and between habitats, taxonomic differences and corresponding discrimination markers of gut microbiota in the control group and medicated group were assessed. Results: Compared with the control group, the medicated group showed a significantly decreased abundance of Bacteroidetes (P < 0.05) and significantly increased abundance of Actinobacteria at the phylum level, a significantly decreased abundance of Bacteroidaceae (P < 0.05) and significantly increased abundance of Bifidobacteriaceae at the family level and a significantly decreased abundance of Blautia and Bacteroides (P < 0.05) and significantly increased abundance of Bifidobacterium, Lactobacillus and Roseburia at the genus level. Compared to the control group, the medicated group had decreased abundance, diversity, and genetic diversity of the communities and increased coverage, but the differences were not significant (P > 0.05); the markers that differed significantly between communities at the genus level and influenced the differences between groups were Blautia, Bacteroides, Bifidobacterium and Lactobacillus. Conclusions: MG patients have obvious gut microbiota-associated metabolic disorders. Fufang Huangqi Decoction regulates the gut microbiota in patients with class I or II MG by reducing the abundance of Blautia and Bacteroides and increasing the abundance of Bifidobacterium and Lactobacillus. The correlation between gut microbiota and MG may be related to cell-mediated immunity.

9.
Nat Prod Res ; 36(19): 5009-5015, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33908333

RESUMO

ABATRACTNine compounds, five phenolic glycosides (1, 2, 4-6), three phenylpropanoids (7-9), and a furanone glycoside (3), were isolated from aqueous soluble extract of the dried roots of Anemone chinensis Bunge. The structures of new compounds (1-4) were elucidated by comprehensive spectroscopic data analysis as well as chemical evidence. Pulsatillanin A (1) demonstrated significant antioxidant effects through scavenging free radical in DPPH assay, and relieved the oxidative stress in LPS-induced RAW 264.7 cells by reducing ROS production, enhancing antioxidant enzyme SOD activity, replenishing depleted GSH in a dose-dependent manner. Western blot analysis revealed that 1 showed antioxidant activity via activating Nrf2 signaling pathway.[Formula: see text].


Assuntos
Anemone , Antioxidantes , Antioxidantes/química , Glicosídeos/química , Glicosídeos/farmacologia , Lipopolissacarídeos , Fator 2 Relacionado a NF-E2 , Fenóis/análise , Extratos Vegetais/química , Espécies Reativas de Oxigênio , Superóxido Dismutase
10.
Mol Neurobiol ; 59(5): 3294-3309, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35303280

RESUMO

Alzheimer's disease (AD) is an age-related neurological disorder. Currently, there is no effective cure for AD due to its complexity in pathogenesis. In light of the complex pathogenesis of AD, the traditional Chinese medicine (TCM) formula Kai-Xin-San (KXS), which was used for amnesia treatment, has been proved to improve cognitive function in AD animal models. However, the active ingredients and the mechanism of KXS have not yet been clearly elucidated. In this study, network pharmacology analysis predicts that KXS yields 168 candidate compounds acting on 863 potential targets, 30 of which are associated with AD. Enrichment analysis revealed that the therapeutic mechanisms of KXS for AD are associated with the inhibition of Tau protein hyperphosphorylation, inflammation, and apoptosis. Therefore, we chose 7-month-old senescence-accelerated mouse prone 8 (SAMP8) mice as AD mouse model, which harbors the behavioral and pathological hallmarks of AD. Subsequently, the potential underlying action mechanisms of KXS on AD predicted by the network pharmacology analyses were experimentally validated in SAMP8 mice after intragastric administration of KXS for 3 months. We observed that KXS upregulated AKT phosphorylation, suppressed GSK3ß and CDK5 activation, and inhibited the TLR4/MyD88/NF-κB signaling pathway to attenuate Tau hyperphosphorylation and neuroinflammation, thus suppressing neuronal apoptosis and improving the cognitive impairment of aged SAMP8 mice. Taken together, our findings reveal a multi-component and multi-target therapeutic mechanism of KXS for attenuating the progression of AD, contributing to the future development of TCM modernization, including KXS, and broader clinical application.


Assuntos
Doença de Alzheimer , Medicamentos de Ervas Chinesas , Doença de Alzheimer/tratamento farmacológico , Animais , Apoptose , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa , Camundongos , Proteínas tau
11.
Front Plant Sci ; 13: 924565, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35755640

RESUMO

Although low light stress seriously affects florets fertility and grain number during the reproductive period, crops can be fertilized by heterologous pollen to alleviate the reduction of grain number. However, wheat is strongly autogamous, how to change to outcross after low light remains unclear. To understand the mechanisms of this change process, an approach combined morphological, physiological, and transcriptomic analyses was performed under low light stress imposed at the young microspore stage the booting stage from tetrad to uni-nucleate microspores stage. The results showed that low light stress caused pollen abortion, and the unfertilized ovary is fertilized by heterologous pollen after floret opening. Compared to control, the opening angle of lemma and glume were increased by 11.6-48.6 and 48.4-78.5%, respectively. The outcross of stressed wheat compensated for the 2.1-18.0% of grain number loss. During this process, phytohormones played an important role. Jasmonic acid (JA) and methyl jasmonate (MeJA) levels in spikelets were increased. Meanwhile, lignin and cellulose content decreased, and genes associated with cell wall related GO terms were enriched. Among the differentially expressed genes (DEGs), were identified 88-710 transcription factors genes, of which some homologs in Arabidopsis are proposed to function in lignin and cellulose, influencing the glume and lemma opening. Our finding can provide new insight into a survival mechanism to set seeds through pollination way alteration in the absence of self-fertilization after the stress of adversity.

12.
Front Microbiol ; 12: 810511, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069513

RESUMO

Raw milk is susceptible to microbial contamination during transportation and storage. Pseudomonas fluorescens producing heat-resistant enzymes have become the most common and harmful psychrophilic microorganisms in the cold chain logistics of raw milk. To rapidly detect P. fluorescens in raw milk, the protease gene aprX was selected as a detection target to construct a set of primers with strong specificity, and a loop-mediated isothermal amplification (LAMP) assay was established. The detection thresholds of the LAMP assay for pure cultured P. fluorescens and pasteurized milk were 2.57 × 102 and 3 × 102 CFU/mL, respectively. It had the advantages over conventional method of low detection threshold, strong specificity, rapid detection, and simple operation. This LAMP assay can be used for online monitoring and on-site detection of P. fluorescens in raw milk to guarantee the quality and safety of dairy products.

13.
J Agric Food Chem ; 67(40): 11089-11098, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31509411

RESUMO

Reactive oxygen species and subsequent oxidative stress are reported to play important roles in chronic metabolic diseases. Plant-derived polyphenols, especially food-derived phenolics, have attracted a lot of attention due to their potential usage against oxidative stress-related diseases. The leaf of Psidium guajava (known as guava) is regarded as a good resource of polyphenols and its products are commercially available in Japan as functional foods against multiple chronic metabolism disorders. In the course of finding novel polyphenols with antioxidative activities from guava leaf, 11 acylated phenolic glycosides (1-11), including 5 new oleuropeic acid-conjugated phenolic glycosides, named guajanosides A-E (1, 2, and 5-7), along with 17 known meroterpenoides (12-28), were isolated and identified. Their structures were determined by spectroscopic data analysis, chemical degradation, and acid hydrolysis. Compounds 1, 2, and 5-11 displayed potent reactive oxygen species-scavenging activity in lipopolysaccharide-stimulated RAW 264.7 macrophage cells. Western blot revealed that compound 6 markedly increased the expression levels of nuclear factor-erythroid 2-related factor 2 (Nrf2), NAD(P)H quinone dehydrogenase 1 (NQO1), and the glutamate-cysteine ligase catalytic subunit. The current study revealed the presence of oleuropeic acid-derived phenolic glycosides in guava leaf and highlighted the potential usage of this type of phenolics against oxidative stress-related metabolic diseases via activation of the Nrf2 signaling pathway.


Assuntos
Sequestradores de Radicais Livres/farmacologia , Glicosídeos/farmacologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Psidium/química , Espécies Reativas de Oxigênio/metabolismo , Animais , Sequestradores de Radicais Livres/química , Glicosídeos/química , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fenóis/química , Extratos Vegetais/química , Folhas de Planta/química , Células RAW 264.7
14.
ISA Trans ; 64: 303-313, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27342994

RESUMO

In this paper, an adaptive two-degree-of-freedom (2Dof) proportional-integral (PI) controller is proposed for the speed control of permanent magnet synchronous motor (PMSM). Firstly, an enhanced just-in-time learning technique consisting of two novel searching engines is presented to identify the model of the speed control system in a real-time manner. Secondly, a general formula is given to predict the future speed reference which is unavailable at the interval of two bus-communication cycles. Thirdly, the fractional order generalized predictive control (FOGPC) is introduced to improve the control performance of the servo drive system. Based on the identified model parameters and predicted speed reference, the optimal control law of FOGPC is derived. Finally, the designed 2Dof PI controller is auto-tuned by matching with the optimal control law. Simulations and real-time experimental results on the servo drive system of PMSM are provided to illustrate the effectiveness of the proposed strategy.

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