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1.
Small ; : e2310217, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38361221

RESUMO

In this work, multi-layer Ti3 C2 - carbon nanotubes - gold nanoparticles (Ti3 C2 -CNTs-Au) and cyclodextrin metal-organic framework - carbon nanotubes (CD-MOF-CNTs) have been prepared by in situ growth method and used to construct the ultra-sensitive rutin electrochemical sensor for the first time. Among them, the large number of metal active sites of Ti3 C2 , the high electron transfer efficiency of CNTS, and the good catalytic properties of AuNPs significantly enhance the electrochemical properties of the composite carbon nanomaterials. Interestingly, CD-MOF has a unique host-guest recognition and a large number of cavities, molecular gaps, and surface reactive groups, which gives the composite outstanding accumulation properties and selectivity for rutin. Under the optimized conditions, the constructed novel sensor has satisfactory detection performance for rutin in the range of 2 × 10-9 to 8 × 10-7  M with a limit of detection of 6.5 × 10-10  M. In addition, the sensor exhibits amazing anti-interference performance against rutin in some flavonoid compounds and can be used to test natural plant samples (buckwheat, Cymbopogon distans, and flos sophorae immaturus). This work has promising applications in the field of environmental and food analysis, and exploring new directions for the application of Mxene-based composites.

2.
Small ; : e2401346, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700047

RESUMO

Transparent flexible energy storage devices are limited by the trade-off among flexibility, transparency, and charge storage capability of their electrode materials. Conductive polymers are intrinsically flexible, but limited by small capacitance. Pseudocapacitive MXene provides high capacitance, yet their opaque and brittle nature hinders their flexibility and transparency. Herein, the development of synergistically interacting conductive polymer Ti3C2Tx MXene/PEDOT:PSS composites is reported for transparent flexible all-solid-state supercapacitors, with an outstanding areal capacitance of 3.1 mF cm-2, a high optical transparency of 61.6%, and excellent flexibility and durability. The high capacitance and high transparency of the devices stem from the uniform and thorough blending of PEDOT:PSS and Ti3C2Tx, which is associated with the formation of O─H…O H-bonds in the composites. The conductive MXene/polymer composite electrodes demonstrate a rational means to achieve high-capacity, transparent and flexible supercapacitors in an easy and scalable manner.

3.
Mol Pharm ; 21(2): 745-759, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38148514

RESUMO

Starvation therapy is an innovative approach in cancer treatment aimed at depriving cancer cells of necessary resources by impeding tumor angiogenesis or blocking the energy supply. In addition to the commonly observed anaerobic glycolysis energy supply mode, adipocyte-rich tumor tissue triggers the fatty acid energy supply pathway, which fuels the proliferation and metastasis of cancer cells. To completely disrupt these dual-energy-supply pathways, we developed an exceptional nanoreactor. This nanoreactor consisted of yolk-shell mesoporous organosilica nanoparticles (YSMONs) loaded with a fatty acid transport inhibitor (Dox), conjugated with a luminal breast-cancer-specific targeting aptamer, and integrated with a glucose oxidation catalyst (GOx). Upon reaching cancer cells with the assistance of the aptamer, the nanoreactor underwent a structural collapse of the shell triggered by the high concentration of glutathione within cancer cells. This collapse led to the release of GOx and Dox, achieving targeted delivery and exhibiting significant efficacy in starving therapy. Additionally, the byproducts of glucose metabolism, gluconic acid and H2O2, enhanced the acidity and reactive oxygen species levels of the intracellular microenvironment, inducing oxidative damage to cancer cells. Simultaneously, released Dox acted as a potent broad-spectrum anticancer drug, inhibiting the activity of carnitine palmitoyltransferase 1A and exerting marked effects. Combining these effects ensures high anticancer efficiency, and the "dual-starvation" nanoreactor has the potential to establish a novel synergistic therapy paradigm with considerable clinical significance. Furthermore, this approach minimizes damage to normal organs, making it highly valuable in the field of cancer treatment.


Assuntos
Antineoplásicos , Neoplasias da Mama , Nanopartículas , Neoplasias , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Peróxido de Hidrogênio/química , Antineoplásicos/farmacologia , Glutationa , Ácidos Graxos , Nanopartículas/química , Neoplasias/patologia , Linhagem Celular Tumoral , Microambiente Tumoral
4.
Skin Res Technol ; 30(2): e13573, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38303407

RESUMO

BACKGROUND: Facial acne scars are a prevalent concern, leading to the development of various treatment modalities. OBJECTIVES: This review aims to explore the latest advancements in the treatment of facial acne scars, focusing on both surgical and non-surgical methods. METHODS: The non-surgical treatments reviewed include topical medications (such as retinoids and alpha hydroxy acids) and non-invasive procedures (like microdermabrasion and chemical peels). Surgical options discussed are punch excision, subcision, and fractional laser treatments. RESULTS: Combination therapy, integrating both surgical and non-surgical approaches, is frequently utilized to achieve optimal results in scar improvement. CONCLUSION: Recent advancements in the treatment of facial acne scars provide promising options for individuals seeking improvement. However, these treatments have associated risks and potential adverse effects, highlighting the importance of consulting a dermatologist before beginning any treatment regimen.


Assuntos
Acne Vulgar , Abrasão Química , Humanos , Cicatriz/etiologia , Cicatriz/terapia , Cicatriz/patologia , Acne Vulgar/terapia , Acne Vulgar/cirurgia , Dermabrasão , Retinoides/uso terapêutico , Resultado do Tratamento
5.
Mol Ecol ; 32(11): 2850-2868, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36847615

RESUMO

The evergreen versus deciduous leaf habit is an important functional trait for adaptation of forest trees and has been hypothesized to be related to the evolutionary processes of the component species under paleoclimatic change, and potentially reflected in the dynamic history of evergreen broadleaved forests (EBLFs) in East Asia. However, knowledge about the shift of evergreen versus deciduous leaf with the impact of paleoclimatic change using genomic data remains rare. Here, we focus on the Litsea complex (Lauraceae), a key lineage with dominant species of EBLFs, to gain insights into how evergreen versus deciduous trait shifted, providing insights into the origin and historical dynamics of EBLFs in East Asia under Cenozoic climate change. We reconstructed a robust phylogeny of the Litsea complex using genome-wide single-nucleotide variants (SNVs) with eight clades resolved. Fossil-calibrated analyses, diversification rate shifts, ancestral habit, ecological niche modelling and climate niche reconstruction were employed to estimate its origin and diversification pattern. Taking into account studies on other plant lineages dominating EBLFs of East Asia, it was revealed that the prototype of EBLFs in East Asia probably emerged in the Early Eocene (55-50 million years ago [Ma]), facilitated by the greenhouse warming. As a response to the cooling and drying climate in the Middle to Late Eocene (48-38 Ma), deciduous habits were evolved in the dominant lineages of the EBLFs in East Asia. Up to the Early Miocene (23 Ma), the prevailing of East Asian monsoon increased the extreme seasonal precipitation and accelerated the emergence of evergreen habits of the dominant lineages, and ultimately shaped the vegetation resembling that of today.


Assuntos
Evolução Biológica , Mudança Climática , Filogenia , Florestas , Ásia Oriental , Árvores
6.
Electrophoresis ; 44(13-14): 1057-1067, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37015868

RESUMO

Liver cancer is generally considered the leading cause of cancer deaths worldwide, and hepatocellular carcinoma (HCC) contributes to more than 90% of liver cancers. The altered lipid metabolism for rapid cancer cell growth and tumor formation has been frequently proven. In this study, an ambient ionization mass spectrometry technique, rapid evaporative ionization mass spectrometry (REIMS) using a monopolar electric knife, called iKnife, was systematically optimized and employed for ex vivo analysis of 12 human HCC tumor tissue specimens together with the paired paracancerous tissue (PT) and noncancerous liver tissue (NCT) specimens. Nine free fatty acids and 34 phospholipids were tentatively identified according to their extract masses and/or tandem mass spectra. With the help of statistical methods, 7 free fatty acids and 10 phospholipids were distributed differently in 3 types of liver tissue specimens (95% confidence interval). The box plots showed these characterized lipid metabolites varied in PT, HCC, and NCT. Compared with PT and NCT, the upregulations of four common fatty acids FA 18:0, FA 20:4, FA 16:0, and FA 18:1, together with phospholipids PC 36:1, PE 38:3, PE (18:0/20:4), PA (O-36:1), PC (32:1), PC 32:0, PE 34:0, and PC (16:0/18:1), were found in HCC specimens. The sensitivity and specificity of the established statistic model for real-time HCC tumor diagnosis were 100% and 90.5%, respectively. This study demonstrated that the described REIMS technique is a potential method for rapid lipidomic analysis and characterization of HCC tumor tissue.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Lipidômica , Neoplasias Hepáticas/diagnóstico , Ácidos Graxos não Esterificados , Fosfolipídeos/química , Espectrometria de Massas em Tandem
7.
Mol Biol Rep ; 50(8): 6517-6528, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37329481

RESUMO

BACKGROUND: SARGASSUM FUSIFORME: (S. fusiforme) is a brown alga that has been utilized as a medicine for a long time. Polysaccharides extracted from S. fusiforme demonstrate antitumor activities. METHODS: The impact of S. fusiforme polysaccharides (SFPS 191,212) on the proliferation, apoptosis, and cell cycle kinetics of B16F10 murine melanoma cells were thoroughly investigated in this work. The anticancer activities of the SFPS 191,212 compounds were assayed in the B16F10 cells at both transcriptional and translational levels. RESULTS: The compound exhibited concentration-dependent effects. Moreover, SPFS 191,212 increased the numbers of apoptotic cells and arrested the cell cycle in the S phase of the quantitative real-time PCR. From western blotting, it was verified that the SFPS 191,212 treatment improved the expression of Bax, Caspase-9, and Caspase-3 genes and proteins, while it reduced phosphatidylinositol 3 kinase and Bcl-2 genes and proteins, suggesting the involvement of mitochondria. CONCLUSION: Overall, SFPS 191,212 can be further explored as a potential functional food or adjuvant agent for the prevention or treatment of melanoma.


Assuntos
Melanoma , Sargassum , Camundongos , Animais , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Pontos de Checagem do Ciclo Celular , Apoptose , Polissacarídeos/farmacologia
8.
Int Wound J ; 20(6): 2190-2206, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36726192

RESUMO

Pathological scarring is an abnormal outcome of wound healing, which often manifests as excessive proliferation and transdifferentiation of fibroblasts (FBs), and excessive deposition of the extracellular matrix. FBs are the most important effector cells involved in wound healing and scar formation. The factors that promote pathological scar formation often act on the proliferation and function of FB. In this study, we describe the factors that lead to abnormal FB formation in pathological scarring in terms of the microenvironment, signalling pathways, epigenetics, and autophagy. These findings suggest that understanding the causes of abnormal FB formation may aid in the development of precise and effective preventive and treatment strategies for pathological scarring that are associated with improved quality of life of patients.


Assuntos
Queloide , Humanos , Queloide/patologia , Qualidade de Vida , Cicatrização , Fibroblastos/metabolismo , Matriz Extracelular
9.
Opt Express ; 30(19): 34750-34764, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36242480

RESUMO

Fourier ptychography (FP) has been developed as a general imaging tool for various applications. However, the redundancy data has to be enforced to get a stable recovery, leading to a large dataset and a high computational cost. Based on the additive property of the optical pupils in FP recovery, we report batch-based alternating direction methods of multipliers (ADMM) for FP reconstruction. The reported scheme is performed by implementing partial updates in sub-problems of the standard ADMM. We validate the reconstruction performance using both simulated and experimental measurements. Compared with the embedded pupil function recovery (EPRY) algorithm, the proposed algorithms can converge faster and produce higher-quality images.

10.
BMC Cardiovasc Disord ; 22(1): 443, 2022 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-36229771

RESUMO

BACKGROUND: The incidence and mortality of aortic dissection (AD) are increasing. In pathological studies, macrophages, T lymphocytes and dendritic cells were found in the tunica media of the aorta. Acetaldehyde dehydrogenase 2 (ALDH2) gene polymorphisms are associated with a high incidence of hypertension in Asian populations. However, there is no clear evidence of the relationship between ALDH2 and aortic dissection in Asians. The aim of this study was to investigate the incidence of aortic dissection in different ALDH2 genotypes and explore changes in the vasculature. MATERIALS AND METHODS: Three-week-old male mice were administered freshly prepared ß-aminopropionitrile solution dissolved in drinking water (1 g/kg/d) for 28 days to induce TAD. An animal ultrasound imaging system was used to observe the formation of arterial dissection and changes in cardiac function. Subsequently, mice were euthanized by cervical dislocation. The aortas were fixed for HE staining and EVG staining to observe aortic elastic fiber tears and pseudoluma formation under a microscope. RESULTS: Knockout of ALDH2 mitigated ß-aminopropionitrile-induced TAD formation in animal studies. Ultrasound results showed that ALDH2 knockout reduced the degree of ascending aortic widening and the incidence of aortic dissection rupture. Pathological sections of multiple aortic segments showed that the protective effect of ALDH2 knockout was observed in not only the ascending aorta but also the aortic arch and descending aorta. The expression levels of genes related to NK CD56bright cells, Th17 cells, T cells and T helper cells were decreased in ALDH2 knockout mice treated with ß-aminopropionitrile for 28 days. CONCLUSION: ALDH2 knockout protects against aortic dissection by altering the inflammatory response and immune response and protecting elastic fibers.


Assuntos
Aldeído-Desidrogenase Mitocondrial/metabolismo , Aneurisma da Aorta Torácica , Dissecção Aórtica , Ruptura Aórtica , Água Potável , Aminopropionitrilo , Dissecção Aórtica/induzido quimicamente , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/genética , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
11.
J Card Surg ; 37(7): 2197-2201, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35462439

RESUMO

Extended left ventricular septal myectomy remains the gold standard for the treatment of hypertrophic obstructive cardiomyopathy (HOCM) with refractory symptoms. On the basis of traditional modified transaortic Morrow myectomy, we innovatively performed a minimally invasive, video-assisted single-port thoracotomy through the right infra-axillary region. Our procedure can provide good visualization of the left ventricular outflow tract and hypertrophic ventricular septum for accurate resection. It also ensures optimal exposure of the mitral valve in the presence of complex mitral subvalvular structures.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Cardiomiopatia Hipertrófica , Procedimentos Cirúrgicos Cardíacos/métodos , Cardiomiopatia Hipertrófica/cirurgia , Humanos , Valva Mitral/cirurgia , Toracotomia , Resultado do Tratamento
12.
Int J Mol Sci ; 23(2)2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35054982

RESUMO

Lodging is the primary factor limiting high yield under a high plant density. However, an optimal plant height and leaf shape can effectively decrease the lodging risk. Here we studied an ethyl methanesulfonate (EMS)-induced dwarf and a narrow-leaf mutant, dnl2. Gene mapping indicated that the mutant was controlled by a gene located on chromosome nine. Phenotypic and cytological observations revealed that dnl2 showed inhibited cell growth, altered vascular bundle patterning, and disrupted secondary cell wall structure when compared with the wild-type, which could be the direct cause of the dwarf and narrow-leaf phenotype. The phytohormone levels, especially auxin and gibberellin, were significantly decreased in dnl2 compared to the wild-type plants. Transcriptome profiling of the internodes of the dnl2 mutant and wild-type revealed a large number of differentially expressed genes enriched in the cell wall biosynthesis, remodeling, and hormone biosynthesis and signaling pathways. Therefore, we suggest that crosstalk between hormones (the altered vascular bundle and secondary cell wall structure) may contribute to the dwarf and narrow-leaf phenotype by influencing cell growth. These results provide a foundation for DNL2 gene cloning and further elucidation of the molecular mechanism of the regulation of plant height and leaf shape in maize.


Assuntos
Perfilação da Expressão Gênica , Fenótipo , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Transcriptoma , Zea mays/anatomia & histologia , Zea mays/genética , Parede Celular , Mapeamento Cromossômico , Biologia Computacional/métodos , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Estudos de Associação Genética , Genoma de Planta , Estudo de Associação Genômica Ampla , Lignina/metabolismo , Mutação , Reguladores de Crescimento de Plantas/genética , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética
13.
Genet Mol Biol ; 45(4): e20220043, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36288450

RESUMO

Our aim was to investigate molecular features of thalassemia for proper clinical consultation and prevention in Heyuan. In our research, a total of 25,437 positive screening subjects were further subjected to a genetic analysis of α-thalassemia (α-thal) and ß-thalassemia (ß-thal). The deletion of α-thal mutation was tested by Gap-PCR, while the non-deletion of α-thal and ß-thal mutation were identified by the PCR-reverse dot blot (PCR-RDB) technique. Nested PCR detected Hkαα/-- SEA and Hkαα/αα. Among the 25,437 positive screening subjects, 44.09% (11216/25437) subjects were bearers of thalassemia variations, and 30.85% (7847/25437) subjects showed α-thal changes alone. Among the 23 genotypes with α-thal mutation alone, the three common genotypes were --SEA/αα(68.34%), -α3.7/αα(16.44%), and -α4.2/αα(6.38%). Of the 11.50% (2924/25437) subjects and 29 genotypes with ß-thal mutation alone, the three common genotypes were ßCD41-42/ßN(36.22%), ßIVS-II-654/ßN(30.88%), and ß-28/ßN(13.47%). Additionally, of the 1.75% (445/25437) subjects and 55 genotypes showed both α- and ß-thal mutations. We also identified 269 cases of Hb H and six patients of Hkαα. Furthermore, the common genotypes of α-thal and ß-thal mutations were consistent with allele frequencies of mutations. Our study establishes molecular features of thalassemia among Hakka people in Heyuan. It will be useful for developing strategies to prevent thalassemia.

14.
Eur J Neurosci ; 53(3): 861-875, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33128787

RESUMO

Brain-computer interfaces (BCI) help severely paralyzed people communicate with the outside world. One type of BCI depends on eye movements and has high information transfer (ITR) but is tiring for users and not applicable to people with eye dyskinesia. Conversely, independent BCIs enable attention shifts across visual stimuli without eye movement, but at the cost of a lower ITR. Steady-state visual evoked potential (SSVEP) is an oscillatory brain response and typically used as BCI signal sources because of high signal-to-noise ratio (SNR). Considering the effect of attentional modulation on the SSVEP, we proposed the novel concept of one-to-two BCI to optimize existing problems, wherein the target and other stimuli shared the same location. Specifically, two spatially overlapping stimuli were displayed in the center-of-view field, as in the independent BCI, and participants were required to divide their attention between the right and left visual fields, as in the dependent BCI. Using three different design schemes in two experiments, we aimed to provide a new framework for BCI design by exploring the feasibility of a combined BCI that can realize a single stimulus location for two inputs. The results strongly demonstrated that, even when the targets and distractors overlapped spatially, the former evoked stronger SSVEP responses. Notably, the BCI scheme based on the object-based attention could achieve a recognition rate as high as 83.2% and an ITR of 12.5 bits per minute. The feasibility of a one-to-two BCI design, which simplified the keyboard layout, reduced the attention shift, and relieved user fatigue, was established.


Assuntos
Interfaces Cérebro-Computador , Potenciais Evocados Visuais , Eletroencefalografia , Movimentos Oculares , Humanos , Estimulação Luminosa
15.
Nanotechnology ; 32(1): 015402, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33043900

RESUMO

Composites of reduced graphene oxide (rGO) and layered LiMnO2 (LiMnO2@rGO) were successfully synthesized and demonstrated via a one-pot hydrothermal route at a temperature of 200 °C for 12 h. The obtained LiMnO2@rGO was characterized by x-ray diffraction, transmission electron microscopy, Fourier transform infrared spectra and Raman spectra. Electrochemical performance tests of LiMnO2@rGO and LiMnO2 cathodes exhibited that after graphene oxide was loaded, the discharge capacity and cycling performance were greatly improved, the maximum discharge capacity reached 185.6 mAh g-1 at the current density of 100 mA g-1 with retention capacity higher than 80% even after 100 cycles between 2 and 4.5 V vs. Li+/Li, which is much better than most previous reports (table S1). The principles of the corresponding phenomenon were fully explained by the low electron conductivity, high structural stability and lithium diffusion coefficient of LiMnO2@rGO, which was also proved by cyclic voltammetry testing, electrochemical impedance spectroscopy and relevant equivalent circuit fitting. This work not only provides significant insights into the relationship between the structure and electrochemical performance of electrodes, but also shows the great potential of LiMnO2@rGO composite electrodes applied as the cathode materials of lithium-ion batteries.

16.
Breed Sci ; 71(2): 217-228, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34377070

RESUMO

Maize is the most important staple crop worldwide. Many of its agronomic traits present with a high level of heterosis. Combining ability was proposed to exploit the rule of heterosis, and general combining ability (GCA) is a crucial measure of parental performance. In this study, a recombinant inbred line population was used to construct testcross populations by crossing with four testers based on North Carolina design II. Six yield-relevant traits were investigated as phenotypic data. GCA effects were estimated for three scenarios based on the heterotic group and the number of tester lines. These estimates were then used to identify quantitative trait loci (QTL) and dissect genetic basis of GCA. A higher heritability of GCA was obtained for each trait. Thus, testing in early generation of breeding may effectively select candidate lines with relatively superior GCA performance. The GCA QTL detected in each scenario was slightly different according to the linkage mapping. Most of the GCA-relevant loci were simultaneously detected in all three datasets. Therefore, the genetic basis of GCA was nearly constant although discrepant inbred lines were appointed as testers. In addition, favorable alleles corresponding to GCA could be pyramided via marker-assisted selection and made available for maize hybrid breeding.

17.
Mol Cancer ; 19(1): 157, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33172486

RESUMO

BACKGROUND: Emerging evidence has shown that circular RNAs (circRNAs) play a crucial regulatory role in the occurrence and development of cancer. Exploring the roles and mechanisms of circRNAs in tumorigenesis and progression may help to identify new diagnostic markers and therapeutic targets. In the present study, we investigated the role and regulatory mechanism of hsa_circ_0004872 in gastric cancer (GC). METHODS: qRT-PCR was used to determine the expression of hsa_circ_0004872 in GC tissues and cells. EdU, CCK-8, transwell and scratch wound healing assays were used to assess the role of hsa_circ_0004872 in GC cell proliferation, invasion and migration, respectively. Subcutaneous and tail vein tumor injections in nude mice were used to assess the role of hsa_circ_0004872 in vivo. RIP assay, biotin-coupled probe pull-down assay, FISH and luciferase reporter assay were performed to confirm the relationship between hsa_circ_0004872 and the identified miRNA. ChIP assay, luciferase reporter assay and western blot were used to determine the direct binding of Smad4 to the promoter of the ADAR1 gene. RESULTS: In this study, we found that hsa_circ_0004872 was dramatically downregulated in GC tissues compared with adjacent noncancerous tissues. The expression level of hsa_circ_0004872 was associated with tumor size and local lymph node metastasis. Enforced expression of hsa_circ_0004872 inhibited the proliferation, invasion and migration of GC cells, whereas knockdown of hsa_circ_0004872 had the opposite effects. Nude mice experiments showed that ectopic expression of hsa_circ_0004872 dramatically inhibited tumor growth and metastasis in vivo. Moreover, we demonstrated that hsa_circ_0004872 acted as a "molecular sponge" for miR-224 to upregulate the expression of the miR-224 downstream targets p21 and Smad4. Importantly, we found that the RNA-editing enzyme ADAR1 inhibited hsa_circ_0004872 expression and further led to the upregulation of miR-224. Smad4, the downstream target of miR-224, could further affect hsa_circ_0004872 levels by directly binding to the promoter region of ADAR1 to inhibit ADAR1 expression. CONCLUSIONS: Our findings showed that hsa_circ_0004872 acted as a tumor suppressor in GC by forming a negative regulatory loop consisting of hsa_circ_0004872/miR-224/Smad4/ADAR1. Thus, hsa_circ_0004872 may serve as a potential biomarker and therapeutic target for GC.


Assuntos
Adenosina Desaminase/metabolismo , Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , RNA Circular/genética , Proteínas de Ligação a RNA/metabolismo , Proteína Smad4/metabolismo , Neoplasias Gástricas/patologia , Adenosina Desaminase/genética , Animais , Apoptose , Biomarcadores Tumorais/genética , Movimento Celular , Proliferação de Células , Progressão da Doença , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico , Proteínas de Ligação a RNA/genética , Proteína Smad4/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
18.
J Mol Evol ; 88(4): 361-371, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32189025

RESUMO

The gene cox1 is one of the most reported mitochondrial genes involved in horizontal gene transfer among angiosperms. However, whether different cox1 copies exist in different populations of a species and whether any other novel way except intron homing exists for cox1 intron acquisition is less understood. In this study, we chose Cassytha filiformis, a parasitic plant from the angiosperm family Lauraceae, as an example to study cox1 variation and evolution. We identified the stable and inheritable co-occurrence of two copies of cox1 genes, which were different in base composition and insertion/deletion among samples of a single species, C. filiformis. The bioinformatic analyses revealed that Type I copy had intact open reading frames, but type II copy had premature stop codons and was a pseudogene. Further INDEL characterization, phylogenetic analyses, and CCT comparisons consistently support two different origins for the two types of C. filiformis cox1 genes. Type I cox1 was likely vertically inherited within the magnoliids but it has captured an intron from another species, whereas the entire type II intron-containing cox1 has most likely been transferred integrally from Cuscuta or other Convolvulaceae species. The finding of the two independent horizontal gene transfer events associated with C. filiformis cox1 genes not only promotes our understanding of the evolutionary history of C. filiformis, but also leaves intriguing evolutionary questions that merits further efforts.


Assuntos
Ciclo-Oxigenase 1/genética , Transferência Genética Horizontal , Lauraceae , Proteínas de Plantas/genética , Íntrons , Lauraceae/enzimologia , Lauraceae/genética , Filogenia
19.
BMC Plant Biol ; 20(1): 196, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32380944

RESUMO

BACKGROUND: Maize is one of the most important staple crops and is widely grown throughout the world. Stalk lodging can cause enormous yield losses in maize production. However, rind penetrometer resistance (RPR), which is recognized as a reliable measurement to evaluate stalk strength, has been shown to be efficient and useful for improving stalk lodging-resistance. Linkage mapping is an acknowledged approach for exploring the genetic architecture of target traits. In addition, genomic selection (GS) using whole genome markers enhances selection efficiency for genetically complex traits. In the present study, two recombinant inbred line (RIL) populations were utilized to dissect the genetic basis of RPR, which was evaluated in seven growth stages. RESULTS: The optimal stages to measure stalk strength are the silking phase and stages after silking. A total of 66 and 45 quantitative trait loci (QTL) were identified in each RIL population. Several potential candidate genes were predicted according to the maize gene annotation database and were closely associated with the biosynthesis of cell wall components. Moreover, analysis of gene ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway further indicated that genes related to cell wall formation were involved in the determination of RPR. In addition, a multivariate model of genomic selection efficiently improved the prediction accuracy relative to a univariate model and a model considering RPR-relevant loci as fixed effects. CONCLUSIONS: The genetic architecture of RPR is highly genetically complex. Multiple minor effect QTL are jointly involved in controlling phenotypic variation in RPR. Several pleiotropic QTL identified in multiple stages may contain reliable genes and can be used to develop functional markers for improving the selection efficiency of stalk strength. The application of genomic selection to RPR may be a promising approach to accelerate breeding process for improving stalk strength and enhancing lodging-resistance.


Assuntos
Caules de Planta/genética , Seleção Artificial , Zea mays/genética , Mapeamento Cromossômico , Cruzamentos Genéticos , Conjuntos de Dados como Assunto , Genoma de Planta , Fenótipo , Caules de Planta/fisiologia , Locos de Características Quantitativas , Zea mays/fisiologia
20.
Graefes Arch Clin Exp Ophthalmol ; 258(4): 779-785, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31932886

RESUMO

PURPOSE: To automatically detect and classify the lesions of diabetic retinopathy (DR) in fundus fluorescein angiography (FFA) images using deep learning algorithm through comparing 3 convolutional neural networks (CNNs). METHODS: A total of 4067 FFA images from Eye Center at the Second Affiliated Hospital of Zhejiang University School of Medicine were annotated with 4 kinds of lesions of DR, including non-perfusion regions (NP), microaneurysms, leakages, and laser scars. Three CNNs including DenseNet, ResNet50, and VGG16 were trained to achieve multi-label classification, which means the algorithms could identify 4 retinal lesions above at the same time. RESULTS: The area under the curve (AUC) of DenseNet reached 0.8703, 0.9435, 0.9647, and 0.9653 for detecting NP, microaneurysms, leakages, and laser scars, respectively. For ResNet50, AUC was 0.8140 for NP, 0.9097 for microaneurysms, 0.9585 for leakages, and 0.9115 for laser scars. And for VGG16, AUC was 0.7125 for NP, 0.5569 for microaneurysms, 0.9177 for leakages, and 0.8537 for laser scars. CONCLUSIONS: Experimental results demonstrate that DenseNet is a suitable model to automatically detect and distinguish retinal lesions in the FFA images with multi-label classification, which lies the foundation of automatic analysis for FFA images and comprehensive diagnosis and treatment decision-making for DR.


Assuntos
Algoritmos , Aprendizado Profundo , Retinopatia Diabética/diagnóstico , Angiofluoresceinografia/métodos , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Retina/patologia , Idoso , Retinopatia Diabética/classificação , Feminino , Fundo de Olho , Humanos , Masculino , Pessoa de Meia-Idade
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