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1.
Am J Physiol Renal Physiol ; 326(6): F988-F1003, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38634138

RESUMO

Acid sphingomyelinase (ASM) has been reported to increase tissue ceramide and thereby mediate hyperhomocysteinemia (hHcy)-induced glomerular nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3) inflammasome activation, inflammation, and sclerosis. In the present study, we tested whether somatic podocyte-specific silencing of Smpd1 gene (mouse ASM gene code) attenuates hHcy-induced NLRP3 inflammasome activation and associated extracellular vesicle (EV) release in podocytes and thereby suppresses glomerular inflammatory response and injury. In vivo, somatic podocyte-specific Smpd1 gene silencing almost blocked hHcy-induced glomerular NLRP3 inflammasome activation in Podocre (podocyte-specific expression of cre recombinase) mice compared with control littermates. By nanoparticle tracking analysis (NTA), floxed Smpd1 shRNA transfection was found to abrogate hHcy-induced elevation of urinary EV excretion in Podocre mice. In addition, Smpd1 gene silencing in podocytes prevented hHcy-induced immune cell infiltration into glomeruli, proteinuria, and glomerular sclerosis in Podocre mice. Such protective effects of podocyte-specific Smpd1 gene silencing were mimicked by global knockout of Smpd1 gene in Smpd1-/- mice. On the contrary, podocyte-specific Smpd1 gene overexpression exaggerated hHcy-induced glomerular pathological changes in Smpd1trg/Podocre (podocyte-specific Smpd1 gene overexpression) mice, which were significantly attenuated by transfection of floxed Smpd1 shRNA. In cell studies, we also confirmed that Smpd1 gene knockout or silencing prevented homocysteine (Hcy)-induced elevation of EV release in the primary cultures of podocyte isolated from Smpd1-/- mice or podocytes of Podocre mice transfected with floxed Smpd1 shRNA compared with WT/WT podocytes. Smpd1 gene overexpression amplified Hcy-induced EV secretion from podocytes of Smpd1trg/Podocre mice, which was remarkably attenuated by transfection of floxed Smpd1 shRNA. Mechanistically, Hcy-induced elevation of EV release from podocytes was blocked by ASM inhibitor (amitriptyline, AMI), but not by NLRP3 inflammasome inhibitors (MCC950 and glycyrrhizin, GLY). Super-resolution microscopy also showed that ASM inhibitor, but not NLRP3 inflammasome inhibitors, prevented the inhibition of lysosome-multivesicular body interaction by Hcy in podocytes. Moreover, we found that podocyte-derived inflammatory EVs (released from podocytes treated with Hcy) induced podocyte injury, which was exaggerated by T cell coculture. Interstitial infusion of inflammatory EVs into renal cortex induced glomerular injury and immune cell infiltration. In conclusion, our findings suggest that ASM in podocytes plays a crucial role in the control of NLRP3 inflammasome activation and inflammatory EV release during hHcy and that the development of podocyte-specific ASM inhibition or Smpd1 gene silencing may be a novel therapeutic strategy for treatment of hHcy-induced glomerular disease with minimized side effect.NEW & NOTEWORTHY In the present study, we tested whether podocyte-specific silencing of Smpd1 gene attenuates hyperhomocysteinemia (hHcy)-induced nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3) inflammasome activation and associated inflammatory extracellular vesicle (EV) release in podocytes and thereby suppresses glomerular inflammatory response and injury. Our findings suggest that acid sphingomyelinase (ASM) in podocytes plays a crucial role in the control of NLRP3 inflammasome activation and inflammatory EV release during hHcy. Based on our findings, it is anticipated that the development of podocyte-specific ASM inhibition or Smpd1 gene silencing may be a novel therapeutic strategy for treatment of hHcy-induced glomerular disease with minimized side effects.


Assuntos
Hiper-Homocisteinemia , Inflamassomos , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR , Podócitos , Esfingomielina Fosfodiesterase , Animais , Esfingomielina Fosfodiesterase/genética , Esfingomielina Fosfodiesterase/metabolismo , Podócitos/metabolismo , Podócitos/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Hiper-Homocisteinemia/metabolismo , Hiper-Homocisteinemia/complicações , Hiper-Homocisteinemia/genética , Inflamassomos/metabolismo , Inflamassomos/genética , Glomérulos Renais/patologia , Glomérulos Renais/metabolismo , Glomerulonefrite/patologia , Glomerulonefrite/metabolismo , Glomerulonefrite/genética , Inativação Gênica , Camundongos , Camundongos Endogâmicos C57BL , Vesículas Extracelulares/metabolismo , Masculino , Modelos Animais de Doenças
2.
BMC Cancer ; 24(1): 321, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454345

RESUMO

BACKGROUND: Definitive concurrent chemoradiotherapy (dCCRT) is the gold standard for the treatment of locally advanced esophageal squamous cell carcinoma (ESCC). However, the potential benefits of consolidation chemotherapy after dCCRT in patients with esophageal cancer remain debatable. Prospective randomized controlled trials comparing the outcomes of dCCRT with or without consolidation chemotherapy in patients with ESCC are lacking. In this study, we aim to generate evidence regarding consolidation chemotherapy efficacy in patients with locally advanced, inoperable ESCC. METHODS: This is a multicenter, prospective, open-label, phase-III randomized controlled trial comparing non-inferiority of dCCRT alone to consolidation chemotherapy following dCCRT. In total, 600 patients will be enrolled and randomly assigned in a 1:1 ratio to receive either consolidation chemotherapy after dCCRT (Arm A) or dCCRT alone (Arm B). Overall survival will be the primary endpoint, whereas progression-free survival, locoregional progression-free survival, distant metastasis-free survival, and treatment-related toxicity will be the secondary endpoints. DISCUSSION: This study aid in further understanding the effects of consolidation chemotherapy after dCCRT in patients with locally advanced, inoperable ESCC. TRIAL REGISTRATION: ChiCTR1800017646.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimiorradioterapia , Quimioterapia de Consolidação , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/radioterapia , Carcinoma de Células Escamosas do Esôfago/terapia , Carcinoma de Células Escamosas do Esôfago/patologia , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto , Ensaios Clínicos Fase III como Assunto , Estudos de Equivalência como Asunto
3.
Nano Lett ; 23(18): 8643-8649, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37672749

RESUMO

Understanding ultrafast electronic dynamics of the interlayer excitonic states in atomically thin transition metal dichalcogenides is of importance in engineering valleytronics and developing excitonic integrated circuits. In this work, we experimentally explored the ultrafast dynamics of indirect interlayer excitonic states in monolayer type II WSe2/ReS2 heterojunctions using time-resolved photoemission electron microscopy, which reveals its anisotropic behavior. The ultrafast cooling and decay of excited-state electrons exhibit significant linear dichroism. The ab initio theoretical calculations provide unambiguous evidence that this linear dichroism result is primarily associated with the anisotropic nonradiative recombination of indirect interlayer excitonic states. Measuring time-resolved photoemission energy spectra, we have further revealed the ultrafast evolution of excited-state electrons in anisotropic indirect interlayer excitonic states. The findings have important implications for controlling the interlayer moiré excitonic effects and designing anisotropic optoelectronic devices.

4.
Plant J ; 112(1): 135-150, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35942607

RESUMO

Red leaves are common in trees but rare in cereal crops. Red leaves can be used as raw materials for anthocyanin extraction and may have some adaptive significance for plants. In this study, we discovered a red leaf phenotype in the F1 hybrids derived from a cross between two sorghum accessions with green leaf. Histological analysis of red leaves and green leaves showed that red compounds accumulate in mesophyll cells and gradually spreads to the entire leaf blade. In addition, we found chloroplasts degraded more quickly in red leaves than in green leaves based on transmission electron microscopy. Metabolic analysis revealed that flavonoids including six anthocyanins are more abundant in red leaves. Moreover, transcriptome analysis revealed that expression of flavonoid biosynthesis genes was upregulated in red leaves. These observations indicate that flavonoids and anthocyanins in particular, are ideal candidates for the red compounds accumulating in red leaves. Segregation analysis of the red leaf phenotype suggested a genetic architecture consisting of three dominant genes, one (RL1 for RED LEAF1) of which we mapped to a 55-kb region on chromosome 7 containing seven genes. Sequencing, reverse transcription-polymerase chain reaction, and transcriptome analysis suggested Sobic.007G214300, encoding a wall-associated kinase, as the most likely candidate for RL1. Fine mapping the red leaf gene and identifying the metabolites that cause red leaf in sorghum provide us with a better understanding of the red leaf phenotype in the natural population of sorghum.


Assuntos
Antocianinas , Sorghum , Antocianinas/metabolismo , Grão Comestível/metabolismo , Flavonoides/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Pigmentação/genética , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sorghum/genética , Sorghum/metabolismo , Transcriptoma
5.
BMC Genomics ; 24(1): 217, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37098483

RESUMO

BACKGROUND: Small cell lung cancer (SCLC) is a highly lethal malignant tumor. It accounts for approximately 15% of newly diagnosed lung cancers. Long non-coding RNAs (lncRNAs) can regulate gene expression and contribute to tumorigenesis through interactions with microRNAs (miRNAs). However, there are only a few studies reporting the expression profiles of lncRNAs, miRNAs, and mRNAs in SCLC. Also, the role of differentially expressed lncRNAs, miRNAs, and mRNAs in relation to competitive endogenous RNAs (ceRNA) network in SCLC remain unclear. RESULTS: In the present study, we first performed next generation sequencing (NGS) with six pairs of SCLC tumors and adjacent non-cancerous tissues obtained from SCLC patients. Overall, 29 lncRNAs, 48 miRNAs, and 510 mRNAs were found to be differentially expressed in SCLC samples (|log2[fold change] |> 1; P < 0.05). Bioinformatics analysis was performed to predict and construct a lncRNA-miRNA-mRNA ceRNA network, which included 9 lncRNAs, 11 miRNAs, and 392 mRNAs. Four up-regulated lncRNAs and related mRNAs in the ceRNA regulatory pathways were selected and validated by quantitative PCR. In addition, we examined the role of the most upregulated lncRNA, TCONS_00020615, in SCLC cells. We found that TCONS_00020615 may regulate SCLC tumorigenesis through the TCONS_00020615-hsa-miR-26b-5p-TPD52 pathway. CONCLUSIONS: Our study provided the comprehensive analysis of the expression profiles of lncRNAs, miRNAs, and mRNAs of SCLC tumors and adjacent non-cancerous tissues. We constructed the ceRNA networks which may provide new evidence for the underlying regulatory mechanism of SCLC. We also found that the lncRNA TCONS_00020615 may regulate the carcinogenesis of SCLC.


Assuntos
Neoplasias Pulmonares , MicroRNAs , RNA Longo não Codificante , Carcinoma de Pequenas Células do Pulmão , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Carcinoma de Pequenas Células do Pulmão/genética , Redes Reguladoras de Genes , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Neoplasias Pulmonares/genética , Carcinogênese/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/genética
6.
Plant Mol Biol ; 112(6): 309-323, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37378835

RESUMO

Aerial root mucilage can enhance nitrogen fixation by providing sugar and low oxygen environment to the rhizosphere microbiome in Sierra Mixe maize. Aerial root mucilage has long been documented in sorghum (Sorghum bicolor), but little is known about the biological significance, genotypic variation, and genetic regulation of this biological process. In the present study, we found that a large variation of mucilage secretion capacity existed in a sorghum panel consisting of 146 accessions. Mucilage secretion occurred primarily in young aerial roots under adequately humid conditions but decreased or stopped in mature long aerial roots or under dry conditions. The main components of the mucilage-soluble were glucose and fructose, as revealed by sugar profiling of cultivated and wild sorghum. The mucilage secretion capacity of landrace grain sorghum was significantly higher than that of wild sorghum. Transcriptome analysis revealed that 1844 genes were upregulated and 2617 genes were downregulated in mucilage secreting roots. Amongst these 4461 differentially expressed genes, 82 genes belonged to glycosyltransferases and glucuronidation pathways. Sobic.010G120200, encoding a UDP-glycosyltransferase, was identified by both GWAS and transcriptome analysis as a candidate gene, which may be involved in the regulation of mucilage secretion in sorghum through a negative regulatory mechanism.


Assuntos
Sorghum , Sorghum/genética , Sorghum/metabolismo , Transcriptoma , Açúcares/metabolismo , Estudo de Associação Genômica Ampla , Polissacarídeos/metabolismo , Perfilação da Expressão Gênica , Grão Comestível/genética , Variação Genética
7.
Br J Cancer ; 129(11): 1787-1792, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37864049

RESUMO

BACKGROUND: This prospectively randomised, double-blinded, placebo-controlled, multicenter Phase 3 clinical trial was conducted to assess the efficacy and safety profile of nimotuzumab (nimo) plus concurrent chemo-radiotherapy (CCRT) in patients with unresectable locally advanced ESCC. METHODS: Patients were randomly assigned (1:1) to receive CCRT plus nimotuzumab or placebo. The primary endpoint was overall survival (OS). In addition, interim analysis for short-term response rate was pre-defined. RESULTS: A total of 201 patients were randomised into two groups. Eighty patients in the nimo group and eighty-two in the placebo group were evaluable. Three to six months after treatment, 26 (32.5%) patients achieved complete response (CR) in the nimo group, and 10 (12.2%) in the placebo group (P = 0.002). The ORR of the nimo group was significantly higher than the placebo group (93.8% vs. 72.0%, P < 0.001). The two groups' grade 3-5 adverse drug reactions were 11.1% vs. 10.9% (P > 0.05). CONCLUSIONS: Nimotuzumab, in combination with chemo-radiotherapy, increased the CRR and ORR with a good safety profile. The OS is needed to be followed and finally analysed. CLINICAL TRIAL REGISTRATION: NCT02409186.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Esofágicas/tratamento farmacológico , Quimiorradioterapia
8.
Theor Appl Genet ; 136(3): 45, 2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36905488

RESUMO

KEY MESSAGE: Leaf senescence in sorghum is primarily controlled by the progression, but not by the onset of senescence. The senescence-delaying haplotypes of 45 key genes accentuated from landraces to improved lines. Leaf senescence is a genetically programmed developmental process and plays a central role for plant survival and crop production by remobilising nutrients accumulated in senescent leaves. In theory, the ultimate outcome of leaf senescence is determined by the onset and progression of senescence, but how these two processes contribute to senescence is not fully illustrated in crops and the genetic basis for them is not well understood. Sorghum (Sorghum bicolor), which is known for the remarkable stay-green trait, is ideal for dissecting the genomic architecture underlying the regulation of senescence. In this study, a diverse panel of 333 sorghum lines was explored for the onset and progression of leaf senescence. Trait correlation analysis showed that the progression of leaf senescence, rather than the onset of leaf senescence, significantly correlated with variations of the final leaf greenness. This notion was further supported by GWAS, which identified 31 senescence-associated genomic regions containing 148 genes, of which 124 were related to the progression of leaf senescence. The senescence-delaying haplotypes of 45 key candidate genes were enriched in lines with extremely prolonged senescence duration, while senescence-promoting haplotypes in those with extremely accelerated senescence. Haplotype combinations of these genes could well explain the segregation of the senescence trait in a recombinant inbred population. We also demonstrated that senescence-delaying haplotypes of candidate genes were under strong selection during sorghum domestication and genetic improvement. Together, this research advanced our understanding of crop leaf senescence and provided a suite of candidate genes for functional genomics and molecular breeding.


Assuntos
Sorghum , Sorghum/genética , Senescência Vegetal , Locos de Características Quantitativas , Fenótipo , Grão Comestível/genética , Genômica
9.
Artigo em Inglês | MEDLINE | ID: mdl-37728827

RESUMO

Young children's adjustment problems were found to be prevalent during the COVID-19 pandemic. Such adjustment problems may be dependent on children's relationships with their parents and children's daily living routine in the family during the pandemic-related school suspension period. This study examines how children's routine mediated the associations between parent-child relationships and child adjustment problems during the fifth wave of the COVID-19 pandemic in Hong Kong, when schools were suspended. The study collected data from 937 parents (87.8% mothers) of children aged 5-12 (M = 7.35 years, SD = 2.09; 50.5% girls). Parents reported on parent-child relationships, children's daily living routine, and child adjustment problems in an online survey. Our findings from structural equation modeling indicate that parent-child closeness was negatively related to child adjustment problems, whereas conflict was positively related to child adjustment problems. Children's routine mediated the associations between parent-child relationships (i.e., closeness and conflict) and child externalizing problems. However, children's routine did not mediate the associations between parent-child relationships (i.e., closeness and conflict) and child internalizing problems. The findings show that parents should be helped to establish routine, especially in difficult times when young children experience turbulence in their daily life, so as to reduce their adjustment problems, in particular of an externalizing nature.

10.
FASEB J ; 35(10): e21907, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34516679

RESUMO

This study investigated the effect of apela on renal function and anti-inflammatory effect on whole body and kidney tissue in mice with type I cardiorenal syndrome (CRS). The murine type I CRS model was established and apela was subcutaneously infused for two weeks. Cardiac and renal functions were evaluated by echocardiography and blood biochemistry, respectively. The systemic and renal inflammatory responses were examined with molecular biological and histological methods. Human renal glomerular endothelial cells (RGECs) were used to evaluate the adhesion effect of monocytes in vitro. Compared to mice from the control group (CRS + vehicle), the plasma levels of N-terminal pro-brain natriuretic peptide, blood urea nitrogen and creatinine were significantly decreased, while the mean left ventricular ejection fraction was increased in apela-treated CRS mice at the 4th week. The expression of monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α) in the circulation and kidney was decreased in apela-treated mice compared with control mice, and apela improved cardio-renal pathology in mice with type I CRS. Additionally, Apela significantly suppressed the expression of MCP-1, TNF-α, intercellular adhesion molecule-1 and vascular intercellular adhesion molecule-1 in RGECs induced by angiotensin II (Ang II), and inhibited the promoting effect of Ang II on the adhesion of THP-1 cells to RGECs. Western blot results showed that the expression of phosphorylated nuclear factor kappa B (phospho-NFκB) in CRS mice was increased, but the expression of phospho-NFκB was down-regulated after apela treatment. Furthermore, apela significantly inhibited the Ang II-mediated increase in phospho-NFκB expression in RGECs in vitro, but the administration of an apelin peptide jejunum receptor (APJ) inhibitor blocked the inhibitory effect of apela. This study revealed that apela improves cardiorenal function and reduces systemic and renal inflammatory response in type I CRS mice and the apela/APJ system may alleviate renal inflammatory responses by inhibiting the NFκB signalling pathway.


Assuntos
Síndrome Cardiorrenal/complicações , Síndrome Cardiorrenal/patologia , Inflamação/complicações , Inflamação/prevenção & controle , Rim , Hormônios Peptídicos/metabolismo , Animais , Coração/fisiologia , Coração/fisiopatologia , Humanos , Inflamação/patologia , Rim/patologia , Rim/fisiologia , Rim/fisiopatologia , Glomérulos Renais/citologia , Camundongos , NF-kappa B/metabolismo , Fosforilação , Células THP-1
11.
Clin Nephrol ; 97(6): 328-338, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35142283

RESUMO

Deletions involving the TSC2 and PKD1 genes lead to tuberous sclerosis complex (TSC) and autosomal dominant polycystic kidney disease (ADPKD), which is known as TSC2-PKD1 contiguous gene deletion syndrome (PKDTS). PKDTS leads to severe symptoms and death. There are few reported cases of PKDTS, the phenotypic descriptions are poor, and detailed statistics and descriptions of the time of onset and prognosis of PKDTS are lacking. This is the first study to report on the clinical data of PKDTS patients in China. We analyzed all cases including Chinese individuals and summarized the clinical manifestations and genetic characteristics. Our study was the first to use a combination of exome sequencing and multiplex ligation-dependent probe amplification (MLPA) to screen and diagnose PKDTS. We found that many PKDTS patients have the following: multiple renal cysts; angiofibromas (≥ 3) or fibrous cephalic plaque; subependymal nodules; seizures; intellectual disability. PKDTS develops into polycystic kidney disease from before birth to 17 years old and the time of occurrence of end-stage renal disease or dialysis was 21.62 ± 12.87 years of age, which was significantly earlier than in ADPKD caused by PKD1 mutation. Compared with non-Chinese individuals of diverse ancestry, Chinese people have significant differences in the clinical characteristics, including ungual fibromas (≥ 2), and shagreen patch. Five novel large deletions were identified in Chinese. We found no relationship between the clinical phenotype and the genotype. We combined exome sequencing with MLPA to develop a diagnostic method for PKDTS.


Assuntos
Rim Policístico Autossômico Dominante , Rim Policístico Autossômico Recessivo , Canais de Cátion TRPP/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética , Adolescente , Adulto , Criança , Deleção de Genes , Estudos de Associação Genética , Humanos , Mutação , Rim Policístico Autossômico Dominante/diagnóstico , Rim Policístico Autossômico Dominante/genética , Rim Policístico Autossômico Recessivo/genética , Esclerose Tuberosa , Proteínas Supressoras de Tumor/genética , Adulto Jovem
12.
J Chem Phys ; 156(7): 074701, 2022 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-35183079

RESUMO

We theoretically investigate the high-order harmonic generation (HHG) of the monolayer hexagonal boron nitride by two-color laser pulses, based on the ab initio time-dependent density-functional theory. We find that the waveform of the two-color laser field can dramatically control the harmonic spectrum. The two-color laser field can enhance the harmonic radiation more efficiently than the monochromatic pulse laser with the same incident energy. We investigate the influence of incident laser pulse parameters on the harmonic radiation, such as the relative phase of the two-color field, the amplitude ratio between component electric fields, and the laser orientation. We show that the HHG spectrum is controlled by both the electric field and the vector potential. The electronic band structure and the laser-matter energy transfer play an important role in determining the laser polarization for optimal HHG in the hBN crystal. Our work supplies a scheme to manipulate HHGs in two-dimensional materials and provides a potential methodology for the generation of intense extreme-ultraviolet pulses.

13.
J Exp Bot ; 72(10): 3554-3568, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33684202

RESUMO

Leaf senescence is important for crop yield as delaying it can increase the average yield. In this study, population genetics and transcriptomic profiling were combined to dissect its genetic basis in maize. To do this, the progenies of an elite maize hybrid Jidan27 and its parental lines Si-287 (early senescence) and Si-144 (stay-green), as well as 173 maize inbred lines were used. We identified two novel loci and their candidate genes, Stg3 (ZmATG18b) and Stg7 (ZmGH3.8), which are predicted to be members of autophagy and auxin pathways, respectively. Genomic variations in the promoter regions of these two genes were detected, and four allelic combinations existed in the examined maize inbred lines. The Stg3Si-144/Stg7Si-144 allelic combination with lower ZmATG18b expression and higher ZmGH3.8 expression could distinctively delay leaf senescence, increase ear weight and the improved hybrid of NIL-Stg3Si-144/Stg7Si-144 × Si-144 significantly reduced ear weight loss under drought stress, while opposite effects were observed in the Stg3Si-287/Stg7Si-287 combination with a higher ZmATG18b expression and lower ZmGH3.8 expression. Thus, we identify a potential interaction between autophagy and auxin which could modulate the timing of maize leaf senescence.


Assuntos
Ácidos Indolacéticos , Zea mays , Autofagia/genética , Regulação da Expressão Gênica de Plantas , Folhas de Planta/genética , Zea mays/genética
14.
Plant Cell ; 30(10): 2286-2307, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30309900

RESUMO

Sorghum (Sorghum bicolor) is the fifth most popular crop worldwide and a C4 model plant. Domesticated sorghum comes in many forms, including sweet cultivars with juicy stems and grain sorghum with dry, pithy stems at maturity. The Dry locus, which controls the pithy/juicy stem trait, was discovered over a century ago. Here, we found that Dry gene encodes a plant-specific NAC transcription factor. Dry was either deleted or acquired loss-of-function mutations in sweet sorghum, resulting in cell collapse and altered secondary cell wall composition in the stem. Twenty-three Dry ancestral haplotypes, all with dry, pithy stems, were found among wild sorghum and wild sorghum relatives. Two of the haplotypes were detected in domesticated landraces, with four additional dry haplotypes with juicy stems detected in improved lines. These results imply that selection for Dry gene mutations was a major step leading to the origin of sweet sorghum. The Dry gene is conserved in major cereals; fine-tuning its regulatory network could provide a molecular tool to control crop stem texture.


Assuntos
Variação Genética , Proteínas de Plantas/genética , Sorghum/genética , Fatores de Transcrição/genética , Parede Celular/genética , Parede Celular/metabolismo , Grão Comestível/genética , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Estudo de Associação Genômica Ampla , Haplótipos , Proteínas de Plantas/metabolismo , Caules de Planta/fisiologia , Seleção Genética , Sorghum/fisiologia
15.
Theor Appl Genet ; 134(7): 1899-1924, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33655424

RESUMO

KEY MESSAGE: The importance and potential of the multi-purpose crop sorghum in global food security have not yet been fully exploited, and the integration of the state-of-art genomics and high-throughput technologies into breeding practice is required. Sorghum, a historically vital staple food source and currently the fifth most important major cereal, is emerging as a crop with diverse end-uses as food, feed, fuel and forage and a model for functional genetics and genomics of tropical grasses. Rapid development in high-throughput experimental and data processing technologies has significantly speeded up sorghum genomic researches in the past few years. The genomes of three sorghum lines are available, thousands of genetic stocks accessible and various genetic populations, including NAM, MAGIC, and mutagenised populations released. Functional and comparative genomics have elucidated key genetic loci and genes controlling agronomical and adaptive traits. However, the knowledge gained has far away from being translated into real breeding practices. We argue that the way forward is to take a genome-based approach for tailored designing of sorghum as a multi-functional crop combining excellent agricultural traits for various end uses. In this review, we update the new concepts and innovation systems in crop breeding and summarise recent advances in sorghum genomic researches, especially the genome-wide dissection of variations in genes and alleles for agronomically important traits. Future directions and opportunities for sorghum breeding are highlighted to stimulate discussion amongst sorghum academic and industrial communities.


Assuntos
Melhoramento Vegetal , Sorghum/genética , Agricultura , Alelos , Grão Comestível/genética , Genética Populacional , Genômica , Fenótipo
16.
Global Health ; 17(1): 10, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33430894

RESUMO

BACKGROUND: During isolation, sharing physical activity experiences on social network sites (SNS) can enhance individual social connectedness. The objective of the present study was to examine the associations between sharing physical activity experiences on SNS, positive self-presentation, positive feedback, and social connectedness during isolation. METHODS: Based on the Physical Activity Experience Sharing Scale, Social Connectedness Scale, Positive Self-Presentation Scale, and Online Positive Feedback Scale, we collected 460 questionnaires online from across 31 provinces, municipalities and autonomous regions in China. We used multiple linear regression models to investigate the relationship between variables, and used bootstrapping to test for mediation.. RESULTS: During isolation, sharing physical activity experiences was positively associated with social connectedness (b = 0.308, p < 0.001), as well as with positive self-presentation(b = 0.956, p < 0.001)and positive feedback(b = 0.421, p < 0.001). In addition,we found that positive self-presentation showed a significant positive impact on positive feedback (b = 0.563, p < 0.001), and that positive self-presentation(b = 0.331, p < 0.001) and positive feedback(b = 0.311, p < 0.001) were positively associated with social connectedness. Finally, we found an effect on sharing physical activity experiences indirectly through positive self-presentation (b = 0.316, 95% CI: [0.180, 0.463]),and positive feedback (b = 0.131, 95% CI: [0.063, 0.207]) and that the mediation chain between the two also had a significant impact on social connectedness (b = 0.167, 95% CI: [0.088, 0.251]). CONCLUSIONS: During the COVID-19 pandemic, sharing physical activity experiences on SNS can create a positive, healthy, and energetic personal image, gain recognition from others, and establish new interpersonal relationships.


Assuntos
COVID-19/prevenção & controle , Exercício Físico , Quarentena , Isolamento Social , Rede Social , Adulto , COVID-19/epidemiologia , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Inquéritos e Questionários
17.
BMC Genomics ; 21(1): 112, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005168

RESUMO

BACKGROUND: In sorghum (Sorghum bicolor), one paramount breeding objective is to increase grain quality. The nutritional quality and end use value of sorghum grains are primarily influenced by the proportions of tannins, starch and proteins, but the genetic basis of these grain quality traits remains largely unknown. This study aimed to dissect the natural variation of sorghum grain quality traits and identify the underpinning genetic loci by genome-wide association study. RESULTS: Levels of starch, tannins and 17 amino acids were quantified in 196 diverse sorghum inbred lines, and 44 traits based on known metabolic pathways and biochemical interactions amongst the 17 amino acids calculated. A Genome-wide association study (GWAS) with 3,512,517 SNPs from re-sequencing data identified 14, 15 and 711 significant SNPs which represented 14, 14, 492 genetic loci associated with levels of tannins, starch and amino acids in sorghum grains, respectively. Amongst these significant SNPs, two SNPs were associated with tannin content on chromosome 4 and colocalized with three previously identified loci for Tannin1, and orthologs of Zm1 and TT16 genes. One SNP associated with starch content colocalized with sucrose phosphate synthase gene. Furthermore, homologues of opaque1 and opaque2 genes associated with amino acid content were identified. Using the KEGG pathway database, six and three candidate genes of tannins and starch were mapped into 12 and 3 metabolism pathways, respectively. Thirty-four candidate genes were mapped into 16 biosynthetic and catabolic pathways of amino acids. We finally reconstructed the biosynthetic pathways for aspartate and branched-chain amino acids based on 15 candidate genes identified in this study. CONCLUSION: Promising candidate genes associated with grain quality traits have been identified in the present study. Some of them colocalized with previously identified genetic regions, but novel candidate genes involved in various metabolic pathways which influence grain quality traits have been dissected. Our study acts as an entry point for further validation studies to elucidate the complex mechanisms controlling grain quality traits such as tannins, starch and amino acids in sorghum.


Assuntos
Redes Reguladoras de Genes , Estudo de Associação Genômica Ampla/métodos , Locos de Características Quantitativas , Sorghum/química , Mapeamento Cromossômico , Grão Comestível/química , Grão Comestível/genética , Grão Comestível/normas , Desequilíbrio de Ligação , Melhoramento Vegetal , Proteínas de Plantas/genética , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Sorghum/genética , Amido/análise , Taninos/análise
18.
Small ; 15(45): e1903270, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31535783

RESUMO

Metal-free ultralong organic phosphorescence (UOP) materials have attracted significant attention owing to their anomalous photophysical properties and potential applications in various fields. Here, three pyrimidine-based organic luminogens, 9-(pyrimidin-2-yl)-9H-carbazole, 9-(4,6-dimethylpyrimidin-2-yl)-9H-carbazole, and 9-(5-bromopyrimidin-2-yl)-9H-carbazole are designed and synthesized, which show efficient yellow UOP with the longest lifetimes up to 1.37 s and the highest absolute phosphorescence quantum yields up to 23.6% under ambient conditions. Theoretical calculations, crystal structures, and photophysical properties of these compounds reveal that intramolecular hydrogen bonding, intermolecular π-π interactions, and intermolecular electronic coupling are responsible for forming dimers and generating highly efficient UOP. Their efficacy as solid materials for data encryption is demonstrated.

19.
J Xray Sci Technol ; 27(3): 559-572, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31177257

RESUMO

BACKGROUND: For sparse and limited angle projection Computed Tomography (CT), the reconstructed image usually suffers from considerable artifacts due to undersampled data. OBJECTIVE: To improve image reconstruction quality of sparse and limited angle projection CT, this study tested a novel reconstruction algorithm based on Dictionary Learning (DL) from sparse and limited projections. METHODS: The study used signal sparse representation and feature extraction to render the DL technology, which is constrained by L2 and Lp norms, respectively. A Lp Norm Dictionary Learning term is suitable for regular term of objective function for CT image reconstruction. This is helpful for solving the objective function by combining algorithm of ART. Based on these features, the new algorithm of ART-DL-Lp is proposed for CT image reconstruction. The alternate solving strategy of the algorithm of "ART first, then adaptive DL" is provided in sequence. The impact on reconstruction results of ART-DL-Lp at different p values (0 < p < 1) is also considered. RESULTS: For non-ideal projections with noise, the digital experiments show that ART-DL-Lp data were superior to those of ART, SART, and ART-DL-L2. Accordingly, the objective evaluation metrics for non-ideal situation of RMSE, MAE, PSNR, Residuals and SSIM are all better than those of contrasted three algorithms. The metrics curves of ART-DL-Lp algorithm are recorded as the best. In both incomplete projection situations, smaller p-value of ART-DL-Lp algorithm induces more close reconstructed images to the original form and better five objective evaluation metrics. CONCLUSIONS: Overall, the reconstruction efficiency of the proposed ART-DL-Lp for CT imaging using the noisy incomplete projections outperforms ART, SART and ART-DL-L2 algorithms. For ART-DL-Lp algorithm, lower p-values result in better reconstruction performance.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Aprendizado de Máquina , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Artefatos , Imagens de Fantasmas , Razão Sinal-Ruído
20.
J Cell Mol Med ; 22(9): 4328-4334, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29989303

RESUMO

We aimed to compare the diagnostic efficiency of proGRP and NSE on SCLC and to investigate whether the change of proGRP level would predict therapeutic response. Patients who were firstly diagnosed pathologically in Nanjing Chest Hospital and measured proGRP level consecutively were enrolled in the study. ProGRP level was detected using Elecsys ProGRP Assay. Totally 75 SCLC, 234 NSCLC and 264 benign lung diseases (BLD) were enrolled. Both proGRP and NSE levels in SCLC were significantly higher than those in NSCLC and BLD, and proGRP in extensive stage SCLC was higher than which in limited stage (P ≤ .001). The diagnostic efficiency of proGRP on SCLC was higher than that of NSE, but when the two biomarkers were bind together, the diagnostic efficiency was the best. When SCLC was differentiated from NSCLC and BLD, the cut-off values were 114.35 pg/mL and 162.55 pg/mL respectively. For treatment responsive patients, proGRP level decreased markedly after the first cycle of therapy and kept a continued momentum of decline during treatment. But for unresponsive patients, no obvious decline was observed. ProGRP had higher diagnostic efficiency on SCLC when compared to NSE, and it could better predict therapeutic response of pulmonary target lesions on chemotherapy.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Neoplasias Pulmonares/diagnóstico , Neoplasias/diagnóstico , Fragmentos de Peptídeos/sangue , Fosfopiruvato Hidratase/sangue , Carcinoma de Pequenas Células do Pulmão/diagnóstico , Adulto , Idoso , Antineoplásicos/uso terapêutico , Área Sob a Curva , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , China , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/patologia , Fragmentos de Peptídeos/genética , Fosfopiruvato Hidratase/genética , Proteínas Recombinantes/sangue , Proteínas Recombinantes/genética , Estudos Retrospectivos , Sensibilidade e Especificidade , Carcinoma de Pequenas Células do Pulmão/sangue , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/patologia
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