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1.
Plant J ; 114(1): 209-224, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36710629

RESUMO

Reproductive success hinges on precisely coordinated meiosis, yet our understanding of how structural rearrangements of chromatin and phase transitions during meiosis are transcriptionally regulated is limited. In crop plants, detailed analysis of the meiotic transcriptome could identify regulatory genes and epigenetic regulators that can be targeted to increase recombination rates and broaden genetic variation, as well as provide a resource for comparison among eukaryotes of different taxa to answer outstanding questions about meiosis. We conducted a meiotic stage-specific analysis of messenger RNA (mRNA), small non-coding RNA (sncRNA), and long intervening/intergenic non-coding RNA (lincRNA) in wheat (Triticum aestivum L.) and revealed novel mechanisms of meiotic transcriptional regulation and meiosis-specific transcripts. Amidst general repression of mRNA expression, significant enrichment of ncRNAs was identified during prophase I relative to vegetative cells. The core meiotic transcriptome was comprised of 9309 meiosis-specific transcripts, 48 134 previously unannotated meiotic transcripts, and many known and novel ncRNAs differentially expressed at specific stages. The abundant meiotic sncRNAs controlled the reprogramming of central metabolic pathways by targeting genes involved in photosynthesis, glycolysis, hormone biosynthesis, and cellular homeostasis, and lincRNAs enhanced the expression of nearby genes. Alternative splicing was not evident in this polyploid species, but isoforms were switched at phase transitions. The novel, stage-specific regulatory controls uncovered here challenge the conventional understanding of this crucial biological process and provide a new resource of requisite knowledge for those aiming to directly modulate meiosis to improve crop plants. The wheat meiosis transcriptome dataset can be queried for genes of interest using an eFP browser located at https://bar.utoronto.ca/efp_wheat/cgi-bin/efpWeb.cgi?dataSource=Wheat_Meiosis.


Assuntos
Transcriptoma , Triticum , Triticum/genética , Triticum/metabolismo , Meiose/genética , RNA Mensageiro/genética , RNA não Traduzido/genética
2.
J Med Virol ; 96(9): e29921, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39300802

RESUMO

Severe fever with thrombocytopenia syndrome (SFTS) represents an emerging infectious disease characterized by a substantial mortality risk. Early identification of patients is crucial for effective risk assessment and timely interventions. In the present study, least absolute shrinkage and selection operator (LASSO)-Cox regression analysis was conducted to identify key risk factors associated with progression to critical illness at 7-day and 14-day. A nomogram was constructed and subsequently assessed for its predictive accuracy through evaluation and validation processes. The risk stratification of patients was performed using X-tile software. The performance of this risk stratification system was assessed using the Kaplan-Meier method. Additionally, a heat map was generated to visualize the results of these analyses. A total of 262 SFTS patients were included in this study, and four predictive factors were included in the nomogram, namely viral copies, aspartate aminotransferase (AST) level, C-reactive protein (CRP), and neurological symptoms. The AUCs for 7-day and 14-day were 0.802 [95% confidence interval (CI): 0.707-0.897] and 0.859 (95% CI: 0.794-0.925), respectively. The nomogram demonstrated good discrimination among low, moderate, and high-risk groups. The heat map effectively illustrated the relationships between risk groups and predictive factors, providing valuable insights with high predictive and practical significance.


Assuntos
Estado Terminal , Nomogramas , Febre Grave com Síndrome de Trombocitopenia , Humanos , Febre Grave com Síndrome de Trombocitopenia/virologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Fatores de Risco , Medição de Risco/métodos , Phlebovirus/genética , Proteína C-Reativa/análise , Adulto , Progressão da Doença , Aspartato Aminotransferases/sangue
3.
Mar Drugs ; 20(2)2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35200653

RESUMO

Melanin synthesis is a defense mechanism that prevents skin damage, but excessive accumulation of melanin occurs in the skin in various reactions such as pigmentation, lentigines, and freckles. Although anti-melanogenic effects have been demonstrated for various naturally occurring marine products that inhibit and control tyrosinase activity, most studies have not been extended to in vivo applications. Phlorofucofuroeckol-A (PFF-A, 12.5-100 µM) isolated from Ecklonia cava has previously been shown to have tyrosinase-mitigative effects in B16F10 cells, but it has not been evaluated in an in vivo model, and its underlying mechanism for anti-melanogenic effects has not been studied. In the present study, we evaluated the safety and efficacy of PFF-A for anti-melanogenic effects in an in vivo model. We selected low doses of PFF-A (1.5-15 nM) and investigated their mitigative effects on pigmentation stimulated by α-MSH in vivo and their related-mechanism in an in vitro model. The findings suggest that low-dose PFF-A derived from E. cava suppresses pigmentation in vivo and melanogenesis in vitro. Therefore, this study presents the possibility that PFF-A could be utilized as a new anti-melanogenic agent in the cosmeceutical industries.


Assuntos
Benzofuranos/farmacologia , Dioxinas/farmacologia , Melaninas/biossíntese , Phaeophyceae/química , Pigmentação/efeitos dos fármacos , Animais , Benzofuranos/administração & dosagem , Benzofuranos/isolamento & purificação , Linhagem Celular Tumoral , Dioxinas/administração & dosagem , Dioxinas/isolamento & purificação , Relação Dose-Resposta a Droga , Feminino , Masculino , Melanoma Experimental/metabolismo , Camundongos , Peixe-Zebra , alfa-MSH/metabolismo
4.
Chem Biodivers ; 19(3): e202100848, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34997687

RESUMO

Sargassum fusiformis is among the most important edible brown seaweeds in Eastern Asia that contains various bioactive compounds and strong activities. Saringosterol acetate (SA) was successfully isolated from S. fusiformis in our previous research. In this study, SA was investigated for its anticancer effect on MCF-7 breast cancer cells. SA attenuated the survival rate of MCF-7 cells with an IC50 value of 63.16±3.6 µg/mL. Staining with Hoechst 33342 demonstrated that SA treatment mediated apoptotic body generation. SA significantly downregulated Bcl-xL and upregulated Bax, and cleaved PARP, and cleaved caspase 3 in a dose-dependent manner. Thus, these results suggest that SA induced mitochondria-mediated apoptosis in MCF-7 cells, making it a plausible candidate for drug development against breast cancer.


Assuntos
Neoplasias da Mama , Sargassum , Acetatos/farmacologia , Apoptose , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos , Células MCF-7 , Mitocôndrias , Estigmasterol/análogos & derivados
5.
J Cell Mol Med ; 25(2): 1290-1298, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33336526

RESUMO

Early prognostication of neurological outcome in comatose patients after cardiac arrest (CA) is vital for clinicians when assessing the survival time of sufferers and formulating appropriate treatment strategies to avoid the withdrawal of life-sustaining treatment (WLST) from patients. However, there is still a lack of sensitive and specific serum biomarkers for early and accurate identification of these patients. Using an isobaric tag for relative and absolute quantitation (iTRAQ)-based proteomic approach, we discovered 55 differentially expressed proteins, with 39 up-regulated secreted serum proteins and 16 down-regulated secreted serum proteins between three comatose CA survivors with good versus poor neurological recovery. Then, four proteins were selected and were validated via an enzyme-linked immunosorbent assay (ELISA) approach in a larger-scale sample containing 32 good neurological outcome patients and 46 poor neurological outcome patients, and it was confirmed that serum angiotensinogen (AGT) and alpha-1-antitrypsin (SERPINA1) were associated with neurological function and prognosis in CA survivors. A prognostic risk score was developed and calculated using a linear and logistic regression model based on a combination of AGT, SERPINA1 and neuron-specific enolase (NSE) with an area under the curve of 0.865 (P < .001), and the prognostic risk score was positively correlated with the CPC value (R = 0.708, P < .001). We propose that the results of the risk score assessment not only reveal changes in biomarkers during neurological recovery but also assist in enhancing current therapeutic strategies for comatose CA survivors.


Assuntos
Proteínas Sanguíneas/metabolismo , Parada Cardíaca/sangue , Proteoma/metabolismo , Proteômica , Adulto , Idoso , Biomarcadores/sangue , Feminino , Humanos , Marcação por Isótopo , Masculino , Pessoa de Meia-Idade , Prognóstico , Reprodutibilidade dos Testes , Fatores de Risco , Resultado do Tratamento , Adulto Jovem
6.
Microvasc Res ; 138: 104225, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34256086

RESUMO

PURPOSE: Blood-brain barrier (BBB) damage is closely related to various neurological disorders, including bacterial meningitis (BM). Determining a reliable strategy to prevent BBB damage in the context of infection would be highly desirable. In the present study, we investigated the implications of the long non-coding RNA (lncRNA) nuclear paraspeckle assembly transcript 1 (NEAT1) in moderating BBB damage. METHODS: In vitro BBB models were developed by co-culturing hCMEC/D3 cells with glioma cells, whereupon the glioma-exposed endothelial cells (GECs) were treated with a series of mimics, inhibitors, overexpression plasmids, and shRNAs for evaluating whether NEAT1, microRNA-135a (miR-135a) and hypoxia-inducible factor 1α (HIF1α) mediated BBB integrity and permeability. Furthermore, the in vivo biological function of NEAT1 was validated in a mouse model of BBB damage. RESULTS: NEAT1 and HIF1α were determined to be up-regulated, while miR-135a was under-expressed in GECs. As demonstrated by chromatin immunoprecipitation and dual-luciferase reporter assays, NEAT1 could bind to miR-135a, and HIF1α was confirmed as a target of miR-135a. Either overexpression of NEAT1 or depletion of miR-135a impaired the integrity and augmented the permeability of BBB. However, HIF1α silencing could reverse the BBB damage induced by NEAT1 overexpression or by inhibition of miR-135a. In vivo experiments substantiated that knockdown of NEAT1 could alleviate BBB damage in living mice. CONCLUSIONS: Hence, NEAT1 knockdown prevents BBB disruption and exerts promise as a potential target for BM treatment.


Assuntos
Barreira Hematoencefálica/metabolismo , Permeabilidade Capilar , Meningites Bacterianas/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Barreira Hematoencefálica/patologia , Linhagem Celular Tumoral , Técnicas de Cocultura , Modelos Animais de Doenças , Regulação da Expressão Gênica , Células HEK293 , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Lipopolissacarídeos , Masculino , Meningites Bacterianas/induzido quimicamente , Meningites Bacterianas/genética , Meningites Bacterianas/patologia , Camundongos Endogâmicos ICR , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética
7.
Cell Biol Int ; 45(7): 1436-1447, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33675278

RESUMO

Nasopharyngeal carcinoma (NPC) is the subclass of head and neck cancer with the highest incidence among otolaryngology malignancies. A growing amount of evidence has proven that circular RNAs (circRNAs) play key roles in the progression of multiple cancers. It has been reported that circ-NOTCH1 is a novel circRNA and functions as an oncogene in gastric cancer, while the regulatory mechanism of circ-NOTCH1 in NPC remains unknown. In the present research, our findings revealed that circ-NOTCH1 was overexpressed in NPC tissues and cells. Circ-NOTCH1 knockdown suppressed NPC cell proliferation, invasion, and migration. Subsequently, we discovered that c-Myc can activate circ-NOTCH1 by binding to the NOTCH1 promoter. c-Myc functioned as a tumor promoter in NPC cells. Mechanistically, circ-NOTCH1 served as a competitive endogenous RNA to modulate c-Myc expression by sponging miR-34c-5p. Additionally, overexpression of c-Myc reversed the circ-NOTCH1 knockdown-mediated inhibition of NPC cellular progression. Overall, this study suggested that c-Myc-induced circ-NOTCH1 promoted malignant phenotypes of NPC cells by regulating the miR-34c-5p/c-Myc axis.


Assuntos
MicroRNAs/metabolismo , Carcinoma Nasofaríngeo/metabolismo , Neoplasias Nasofaríngeas/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Receptor Notch1/metabolismo , Linhagem Celular Tumoral , Humanos , RNA Circular
8.
Cell Biochem Funct ; 39(4): 546-554, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33474761

RESUMO

Diphlorethohydroxycarmalol (DPHC) is a marine polyphenolic compound derived from brown alga Ishige okamurae. A previously study has suggested that DPHC possesses strong mushroom tyrosinase inhibitory activity. However, the anti-melanogenesis effect of DPHC has not been reported at cellular level. The objective of the present study was to clarify the melanogenesis inhibitory effect of DPHC and its molecular mechanisms in murine melanoma cells (B16F10) and zebrafish model. DPHC significantly inhibited tyrosinase activity and melanin content dose-dependently in α-melanocyte stimulating hormone (α-MSH)-stimulated B16F10 cells. This polyphenolic compound also suppressed the expression of phosphorylation of cAMP response element-binding protein (CREB) by attenuating phosphorylation of cAMP-dependent protein kinase A, resulting in decreased MITF expression levels. Furthermore, DPHC downregulated MITF protein expression levels by promoting the phosphorylation of extracellular signal-regulated kinase. It also inhibited tyrosinase, tyrosinase-related protein 1 (TRP-1), and TRP-2 in α-MSH stimulated B16F10 cells. In in vivo studies using zebrafish, DPHC also markedly inhibited melanin synthesis in a dose-dependent manner. These results demonstrate that DPHC can effectively inhibit melanogenesis in melanoma cells in vitro and in zebrafish in vivo, suggesting that DPHC could be applied in fields of pharmaceutical and cosmeceuticals as a skin-whitening agent. Significance of study: The present study showed for the first time that DPHC could inhibit a-MSH-stimulated melanogenesis via PKA/CREB and ERK pathway in melanoma cells. It also could inhibit pigmentation in vivo in a zebrafish model. This evidence suggests that DPHC has potential as a skin whitening agent. Taken together, DPHC could be considered as a novel anti-melanogenic agent to be applied in cosmetic, food, and medical industry.


Assuntos
Antineoplásicos/farmacologia , Regulação para Baixo/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis/farmacologia , Melanoma/tratamento farmacológico , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/antagonistas & inibidores , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Compostos Heterocíclicos com 3 Anéis/química , Compostos Heterocíclicos com 3 Anéis/isolamento & purificação , Melanoma/metabolismo , Melanoma/patologia , Camundongos , Fator de Transcrição Associado à Microftalmia/antagonistas & inibidores , Fator de Transcrição Associado à Microftalmia/metabolismo , Estrutura Molecular , Phaeophyceae/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Peixe-Zebra/embriologia , alfa-MSH/antagonistas & inibidores , alfa-MSH/metabolismo
9.
Appl Opt ; 60(13): 3604-3608, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33983290

RESUMO

We demonstrate a Fourier-transform-based method for extensive-dynamic-range and high-resolution surface profiling using phase-sensitive spectral-domain white-light interferometry. By combining the frequency and phase of interference fringes, this method is capable of displacement measurement with nanometer-scale resolution and a dynamic range up to several millimeters. The performance of the method is demonstrated by surface profiling of a coin, gauge blocks, and a cell-phone circuit board.

10.
Int J Mol Sci ; 22(4)2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33562632

RESUMO

Nitric oxide (NO) is released by endothelial cells in the blood vessel wall to enhance vasodilation. Marine polyphenols are known to have protective effects against vascular dysfunction and hypertension. The present study is the first to investigate how diphlorethohydroxycarmalol (DPHC) isolated from Ishige okamurae affects calcium levels, resulting in enhanced vasodilation. We examined calcium modulation with the well-known receptors, acetylcholine receptor (AchR) and vascular endothelial growth factor 2 (VEGFR2), which are related to NO formation, and further confirmed the vasodilatory effect of DPHC. We confirmed that DPHC stimulated NO production by increasing calcium levels and endothelial nitric oxide synthase (eNOS) expression. DPHC affected AchR and VEGFR2 expression, thereby influencing transient calcium intake. Specific antagonists, atropine and SU5416, were used to verify our findings. Furthermore, based on the results of in vivo experiments, we treated Tg(flk:EGFP) transgenic zebrafish with DPHC to confirm its vasodilatory effect. In conclusion, the present study showed that DPHC modulated calcium transit through AchR and VEGFR2, increasing endothelial-dependent NO production. Thus, DPHC, a natural marine component, can efficiently ameliorate cardiovascular diseases by improving vascular function.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis/farmacologia , Phaeophyceae/química , Vasodilatadores/farmacologia , Animais , Animais Geneticamente Modificados , Linhagem Celular , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Compostos Heterocíclicos com 3 Anéis/isolamento & purificação , Humanos , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo III/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Colinérgicos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Vasodilatação/efeitos dos fármacos , Vasodilatadores/isolamento & purificação , Peixe-Zebra
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