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1.
BMC Plant Biol ; 24(1): 447, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783192

RESUMO

BACKGROUND: Amino acids are not only the main form of N in rice, but also are vital for its growth and development. These processes are facilitated by amino acid transporters within the plant. Despite their significance, only a few AAP amino acid transporters have been reported. RESULTS: In this study, we observed that there were differences in the expression of amino acid transporter OsAAP7 among 521 wild cultivated rice varieties, and it directly negatively correlated with tillering and grain yield per plant. We revealed that OsAAP7 protein was localized to the endoplasmic reticulum and had absorption and transport affinity for amino acids such as phenylalanine (Phe), lysine (Lys), leucine (Leu), and arginine (Arg) using subcellular localization, yeast substrate testing, fluorescent amino acid uptake, and amino acid content determination. Further hydroponic studies showed that exogenous application of amino acids Phe, Lys and Arg inhibited the growth of axillary buds in the overexpression lines, and promoted the elongation of axillary buds in the mutant lines. Finally, RNA-seq analysis showed that the expression patterns of genes related to nitrogen, auxin and cytokinin pathways were changed in axillary buds of OsAAP7 transgenic plants. CONCLUSIONS: This study revealed the gene function of OsAAP7, and found that blocking of amino acid transporter OsAAP7 with CRISPR/Cas9 technology promoted tillering and yield by determining basic and neutral amino acids accumulation in rice.


Assuntos
Oryza , Proteínas de Plantas , Oryza/genética , Oryza/metabolismo , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Sistemas de Transporte de Aminoácidos/metabolismo , Sistemas de Transporte de Aminoácidos/genética , Plantas Geneticamente Modificadas , Aminoácidos Neutros/metabolismo , Regulação da Expressão Gênica de Plantas , Aminoácidos/metabolismo
2.
Toxicol Appl Pharmacol ; 491: 117066, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39128506

RESUMO

Paclitaxel (PTX) is a microtubule stabilizer that disrupts the normal cycle of microtubule depolymerization and repolymerization, leading to cell cycle arrest and cancer cell death. It is commonly used as a first-line chemotherapeutics for various malignancies, such as breast cancer, non-small cell lung cancer, and ovarian cancer. However, PTX chemotherapy is associated with common and serious side effects, including chemotherapy-induced peripheral neuropathy (CIPN). As cancer treatment advances and survival rates increase, the impact of CIPN on patients' quality of life has become more significant. To date, there is no effective treatment strategy for CIPN. Surtuin3 (SIRT3) is a nicotinamide adenine dinucleotide (NAD+) dependent protein deacetylase located on mitochondria. It transfers the acetyl group of the lysine side chain of acetylated substrate proteins to NAD+, producing deacetylated proteins to regulate mitochondrial energy metabolic processes. SIRT3 has been found to play an important role in various diseases, including aging, neurodegenerative diseases, cancer, heart disease, metabolic diseases, etc. However, the role of SIRT3 in CIPN is still unknown. This study found for the first time that activating SIRT3 helps to improve paclitaxel-induced CIPN. Nicotinamide riboside (NR) can protect dorsal root ganglion (DRG) mitochondria against oxidative damage caused by paclitaxel through activating SIRT3-MnSOD2 and SIRT3-Nrf2 pathway. Moreover, NR can enhance the anticancer activity of paclitaxel. Together, our research provides new strategy and candidate drug for the treatment of CIPN.


Assuntos
Niacinamida , Paclitaxel , Doenças do Sistema Nervoso Periférico , Compostos de Piridínio , Sirtuína 3 , Paclitaxel/toxicidade , Sirtuína 3/metabolismo , Animais , Compostos de Piridínio/farmacologia , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/prevenção & controle , Doenças do Sistema Nervoso Periférico/metabolismo , Niacinamida/análogos & derivados , Niacinamida/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/toxicidade , Camundongos , Humanos , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Masculino
3.
Physiol Plant ; 176(2): e14229, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38413386

RESUMO

Kam Sweet Rice is a high-quality local variety of Guizhou province in China, but most varieties have awns on lemma. In this study, we aimed to obtain awnless varieties of Kam Sweet Rice by blocking the awn development-related gene OsGAD1 using CRISPR/Cas9 technology. We determined that natural variations of the OsGAD1 triggered different lengths of awns of Kam Sweet Rice. We found that the awning rate of the CRISPR lines of OsGAD1 in Guxiangnuo, Goujingao and Gouhuanggang decreased by over 65%, and the number of grains per panicle and yield per plant increased by more than 17% and 20% compared to the wild-types. Furthermore, we indicated that blocking OsGAD1 resulted in an increase of over 2% in the brown rice rate and milled rice rate in these varieties. In addition, the analysis of the transcriptome revealed that the regulation of awn development and yield formation in CRISPR lines of OsGAD1 may involve genes associated with phytohormone and nitrogen pathways. These results suggest that blocking OsGAD1 in Kam Sweet Rice using CRISPR/Cas9 technology can be used for breeding programs seeking high yield and grain quality of Kam Sweet Rice.


Assuntos
Oryza , Oryza/metabolismo , Grão Comestível/genética , Alelos , China
4.
Mol Cell Neurosci ; 125: 103848, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36948232

RESUMO

Astrocytes are key players in neuroinflammation. In response to central nervous system (CNS) injury or disease, astrocytes undergo reactive astrogliosis, which is characterized by increased proliferation, migration, and glial fibrillary acidic protein (GFAP) expression. Activation of the transcription factor nuclear factor-κB (NF-κB) and upregulation of downstream proinflammatory mediators in reactive astrocytes induce a proinflammatory phenotype in astrocytes, thereby exacerbating neuroinflammation by establishing an inflammatory loop. In this study, we hypothesized that excessive fibronectin (FN) derived from reactive astrocytes would induce this proinflammatory phenotype in astrocytes in an autocrine manner. We exogenously treated astrocytes with monomer FN, which can be incorporated into the extracellular matrix (ECM), to mimic plasma FN extravasated through a compromised blood-brain barrier in neuroinflammation. We also induced de novo synthesis and accumulation of astrocyte-derived FN through tumor necrosis factor-α (TNF-α) stimulation. The excessive FN deposition resulting from both treatments initiated reactive astrogliosis and triggered NF-κB signaling in the cultured astrocytes. In addition, inhibition of FN accumulation in the ECM by the FN inhibitor pUR4 strongly attenuated the FN- and TNF-α-induced GFAP expression, NF-κB activation, and proinflammatory mediator production of astrocytes by interrupting FN-ß1 integrin coupling and thus the inflammatory loop. In an in vivo experiment, intrathecal injection of pUR4 considerably ameliorated FN deposition, GFAP expression, and NF-κB activation in inflamed spinal cord, suggesting the therapeutic potential of pUR4 for attenuating neuroinflammation and promoting neuronal function restoration.


Assuntos
Fibronectinas , NF-kappa B , Humanos , NF-kappa B/metabolismo , Fibronectinas/genética , Fibronectinas/metabolismo , Integrina beta1/genética , Integrina beta1/metabolismo , Astrócitos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Células Cultivadas , Doenças Neuroinflamatórias , Gliose/metabolismo , Fenótipo
5.
BMC Health Serv Res ; 24(1): 455, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605373

RESUMO

BACKGROUND: Increasing patient loads, healthcare inflation and ageing population have put pressure on the healthcare system. Artificial intelligence and machine learning innovations can aid in task shifting to help healthcare systems remain efficient and cost effective. To gain an understanding of patients' acceptance toward such task shifting with the aid of AI, this study adapted the Unified Theory of Acceptance and Use of Technology 2 (UTAUT2), looking at performance and effort expectancy, facilitating conditions, social influence, hedonic motivation and behavioural intention. METHODS: This was a cross-sectional study which took place between September 2021 to June 2022 at the National Heart Centre, Singapore. One hundred patients, aged ≥ 21 years with at least one heart failure symptom (pedal oedema, New York Heart Association II-III effort limitation, orthopnoea, breathlessness), who presented to the cardiac imaging laboratory for physician-ordered clinical echocardiogram, underwent both echocardiogram by skilled sonographers and the experience of echocardiogram by a novice guided by AI technologies. They were then given a survey which looked at the above-mentioned constructs using the UTAUT2 framework. RESULTS: Significant, direct, and positive effects of all constructs on the behavioral intention of accepting the AI-novice combination were found. Facilitating conditions, hedonic motivation and performance expectancy were the top 3 constructs. The analysis of the moderating variables, age, gender and education levels, found no impact on behavioral intention. CONCLUSIONS: These results are important for stakeholders and changemakers such as policymakers, governments, physicians, and insurance companies, as they design adoption strategies to ensure successful patient engagement by focusing on factors affecting the facilitating conditions, hedonic motivation and performance expectancy for AI technologies used in healthcare task shifting.


Assuntos
Inteligência Artificial , Revezamento de Tarefas , Humanos , Estudos Transversais , Atitude , Participação do Paciente
6.
Bioprocess Biosyst Eng ; 46(11): 1539-1567, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37540309

RESUMO

Enzymes with industrial significance are typically used in biological processes. However, instability, high sensitivity, and impractical recovery are the major drawbacks of enzymes in practical applications. In recent years, the immobilization technology has attracted wide attention to overcoming these restrictions and improving the efficiency of enzyme applications. Chitosan (CS) is a unique functional substance with biocompatibility, biodegradability, non-toxicity, and antibacterial properties. Chitosan composites are anticipated to be widely used in the near future for a variety of purposes, including as supports for enzyme immobilization, because of their advantages. Therefor this review explores the effects of the chitosan's structure, molecular weight, degree of deacetylation on the enzyme immobilized, effect of key factors, and the enzymes immobilized on chitosan based composites for numerous applications, including the fields of biosensor, biomedical science, food industry, environmental protection, and industrial production. Moreover, this study carefully investigates the advantages and disadvantages of using these composites as well as their potential in the future.


Assuntos
Quitosana , Quitosana/química , Enzimas Imobilizadas/química
7.
Int Heart J ; 64(5): 816-822, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37704406

RESUMO

Subjects with coronary artery disease (CAD) have myocardial ischemia and associated abnormal left ventricular ejection fraction (EF). Heart failure with mildly reduced EF (41-49%) (HFmrEF) is a new subgroup of EF for heart failure. Although prognostic factors for CAD and HF with reduced EF are well known, fewer studies have been conducted on factors related to the survival of CAD and HFmrEF. We recruited study subjects with significant CAD and HFmrEF from our cardiac catheterization data bank. Data were recorded from traceable chart records from our hospital. All-cause and cardiovascular mortality were recorded until December 2019 and served as a follow-up outcome. A total of 348 subjects with CAD and HFmrEF were analyzed. The median duration of follow-up was 37 months. Seventy-eight subjects died during the follow-up period and 30 of them were due to cardiovascular causes. In univariate analyses, those who died were of older ages, and with a lower estimated glomerular filtration rate (eGFR) (47 ± 30 versus 71 ± 30 mL/minute/1.73 m2, P < 0.001), and lower usage of percutaneous coronary intervention (PCI) and beta blockers. In the Cox survival regression analysis, a higher eGFR (hazard ratio 0.980, P < 0.001) was protective, while older age and a higher serum total cholesterol (hazard ratio 1.006, P = 0.048) were related to all-cause mortality for CAD with HFmrEF. Furthermore, a higher eGFR was also associated with less cardiovascular mortality. In conclusion, for subjects with CAD and HFmrEF, a higher eGFR was protective and associated with a lower all-cause and cardiovascular mortality.


Assuntos
Doença da Artéria Coronariana , Insuficiência Cardíaca , Intervenção Coronária Percutânea , Humanos , Doença da Artéria Coronariana/complicações , Volume Sistólico , Função Ventricular Esquerda , Taxa de Filtração Glomerular , Prognóstico , Morte
8.
J Med Internet Res ; 24(7): e34669, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35904853

RESUMO

BACKGROUND: Consumer-grade wearable devices enable detailed recordings of heart rate and step counts in free-living conditions. Recent studies have shown that summary statistics from these wearable recordings have potential uses for longitudinal monitoring of health and disease states. However, the relationship between higher resolution physiological dynamics from wearables and known markers of health and disease remains largely uncharacterized. OBJECTIVE: We aimed to derive high-resolution digital phenotypes from observational wearable recordings and to examine their associations with modifiable and inherent markers of cardiometabolic disease risk. METHODS: We introduced a principled framework to extract interpretable high-resolution phenotypes from wearable data recorded in free-living conditions. The proposed framework standardizes the handling of data irregularities; encodes contextual information regarding the underlying physiological state at any given time; and generates a set of 66 minimally redundant features across active, sedentary, and sleep states. We applied our approach to a multimodal data set, from the SingHEART study (NCT02791152), which comprises heart rate and step count time series from wearables, clinical screening profiles, and whole genome sequences from 692 healthy volunteers. We used machine learning to model nonlinear relationships between the high-resolution phenotypes on the one hand and clinical or genomic risk markers for blood pressure, lipid, weight and sugar abnormalities on the other. For each risk type, we performed model comparisons based on Brier scores to assess the predictive value of high-resolution features over and beyond typical baselines. We also qualitatively characterized the wearable phenotypes for participants who had actualized clinical events. RESULTS: We found that the high-resolution features have higher predictive value than typical baselines for clinical markers of cardiometabolic disease risk: the best models based on high-resolution features had 17.9% and 7.36% improvement in Brier score over baselines based on age and gender and resting heart rate, respectively (P<.001 in each case). Furthermore, heart rate dynamics from different activity states contain distinct information (maximum absolute correlation coefficient of 0.15). Heart rate dynamics in sedentary states are most predictive of lipid abnormalities and obesity, whereas patterns in active states are most predictive of blood pressure abnormalities (P<.001). Moreover, in comparison with standard measures, higher resolution patterns in wearable heart rate recordings are better able to represent subtle physiological dynamics related to genomic risk for cardiometabolic disease (improvement of 11.9%-22.0% in Brier scores; P<.001). Finally, illustrative case studies reveal connections between these high-resolution phenotypes and actualized clinical events, even for borderline profiles lacking apparent cardiometabolic risk markers. CONCLUSIONS: High-resolution digital phenotypes recorded by consumer wearables in free-living states have the potential to enhance the prediction of cardiometabolic disease risk and could enable more proactive and personalized health management.


Assuntos
Doenças Cardiovasculares , Dispositivos Eletrônicos Vestíveis , Doenças Cardiovasculares/diagnóstico , Estudos Clínicos como Assunto , Estudos de Coortes , Humanos , Lipídeos , Aprendizado de Máquina , Fenótipo
9.
J Exp Bot ; 71(16): 4763-4777, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32485736

RESUMO

Nitrogen (N) is a major element necessary for crop yield. In most plants, organic N is primarily transported in the form of amino acids. Here, we show that amino acid permease 1 (AAP1) functions as a positive regulator of growth and grain yield in rice. We found that the OsAAP1 gene is highly expressed in rice axillary buds, leaves, and young panicles, and that the OsAAP1 protein is localized to both the plasma membrane and the nuclear membrane. Compared with the wild-type ZH11, OsAAP1 overexpression (OE) lines exhibited increased filled grain numbers as a result of enhanced tillering, while RNAi and CRISPR (clustered regularly interspaced short palindromic repeat; Osaap1) knockout lines showed the opposite phenotype. In addition, OsAAP1-OE lines had higher concentrations of neutral and acidic amino acids, but lower concentrations of basic amino acids in the straw. An exogenous treatment with neutral amino acids promoted axillary bud outgrowth more strongly in the OE lines than in the WT, RNAi, or Osaap1 lines. Transcriptome analysis of Osaap1 further demonstrated that OsAAP1 may affect N transport and metabolism, and auxin, cytokinin, and strigolactone signaling in regulating rice tillering. Taken together, these results support that increasing neutral amino acid uptake and reallocation via OsAAP1 could improve growth and grain yield in rice.


Assuntos
Aminoácidos Neutros , Oryza , Sistemas de Transporte de Aminoácidos/genética , Grão Comestível/genética , Grão Comestível/metabolismo , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
10.
J Cardiovasc Magn Reson ; 22(1): 10, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-32008575

RESUMO

OBJECTIVES: The imaging features of dilated cardiomyopathy (DCM) overlap with physiological exercise-induced cardiac remodeling in active and otherwise healthy individuals. Distinguishing the two conditions is challenging. This study examined the diagnostic and prognostic roles of exercise stress imaging in asymptomatic patients with suspected DCM. METHODS: Exercise stress cardiovascular magnetic resonance (CMR) was performed in 60 asymptomatic patients with suspected DCM (dilated left ventricle and/or impaired systolic function on CMR), who also underwent DNA sequencing for DCM-causing genetic variants. Confirmed DCM was defined as genotype- and phenotype-positive (G+P+). Another 100 healthy subjects were recruited to establish normal exercise capacities (peak exercise cardiac index; PeakCI). The primary outcome was a composite of all-cause mortality, cardiac decompensation and ventricular arrhythmic events. RESULTS: No patients with confirmed G+P+ DCM had PeakCI exceeding the 35th percentile specific for age and sex. Applying this threshold in G-P+ patients, those with PeakCI below 35th percentile had characteristics similar to confirmed DCM while patients with higher PeakCI were younger, more active and higher longitudinal strain. Adverse cardiovascular events occurred only in patients with low exercise capacity (P = 0.004). CONCLUSIONS: In individuals with suspected DCM, exercise stress CMR demonstrates diagnostic and prognostic potential in distinguishing between pathological DCM and physiological exercise-induced cardiac remodeling.


Assuntos
Cardiomegalia Induzida por Exercícios , Cardiomiopatia Dilatada/diagnóstico por imagem , Teste de Esforço , Imagem Cinética por Ressonância Magnética , Adulto , Doenças Assintomáticas , Cardiomiopatia Dilatada/mortalidade , Cardiomiopatia Dilatada/patologia , Cardiomiopatia Dilatada/fisiopatologia , Causas de Morte , Diagnóstico Diferencial , Progressão da Doença , Tolerância ao Exercício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Volume Sistólico , Função Ventricular Esquerda , Adulto Jovem
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