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1.
Nature ; 610(7933): 656-660, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36289385

RESUMO

Proposed mechanisms for the production of calcium in the first stars (population III stars)-primordial stars that formed out of the matter of the Big Bang-are at odds with observations1. Advanced nuclear burning and supernovae were thought to be the dominant source of the calcium production seen in all stars2. Here we suggest a qualitatively different path to calcium production through breakout from the 'warm' carbon-nitrogen-oxygen (CNO) cycle through a direct experimental measurement of the 19F(p, γ)20Ne breakout reaction down to a very low energy point of 186 kiloelectronvolts, reporting a key resonance at 225 kiloelectronvolts. In the domain of astrophysical interest2, at around 0.1 gigakelvin, this thermonuclear 19F(p, γ)20Ne rate is up to a factor of 7.4 larger than the previous recommended rate3. Our stellar models show a stronger breakout during stellar hydrogen burning than previously thought1,4,5, and may reveal the nature of calcium production in population III stars imprinted on the oldest known ultra-iron-poor star, SMSS0313-67086. Our experimental result was obtained in the China JinPing Underground Laboratory7, which offers an environment with an extremely low cosmic-ray-induced background8. Our rate showcases the effect that faint population III star supernovae can have on the nucleosynthesis observed in the oldest known stars and first galaxies, which are key mission targets of the James Webb Space Telescope9.

2.
Anal Chem ; 96(12): 5056-5064, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38497564

RESUMO

Aptamer-based detection targeting glycoconjugates has attracted significant attention for its remarkable potential in identifying structural changes in saccharides in different stages of various diseases. However, the challenges in screening aptamers for small carbohydrates or glycoconjugates, which contain highly flexible and diverse glycosidic bonds, have hindered their application and commercialization. In this study, we investigated the binding conformations between three glycosidic bond-containing small molecules (GlySMs; glucose, N-acetylneuraminic acid, and neomycin) and their corresponding aptamers in silico, and analyzed factors contributing to their binding affinities. Based on the findings, a novel binding mechanism was proposed, highlighting the central role of the stem structure of the aptamer in binding and recognizing GlySMs and the auxiliary role of the mismatched bases in the adjacent loop. Guided by this binding mechanism, an aptamer with a higher 6'-sialyllactose binding affinity was designed, achieving a KD value of 4.54 ± 0.64 µM in vitro through a single shear and one mutation. The binding mechanism offers crucial guidance for designing high-affinity aptamers, enhancing the virtual screening efficiency for GlySMs. This streamlined workflow filters out ineffective binding sites, accelerating aptamer development and providing novel insights into glycan-nucleic acid interactions.


Assuntos
Aptâmeros de Nucleotídeos , Glicosídeos , Aptâmeros de Nucleotídeos/química , DNA de Cadeia Simples , Sítios de Ligação , Glicoconjugados , Técnica de Seleção de Aptâmeros
3.
Cytokine ; 174: 156478, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38134554

RESUMO

BACKGROUND: To explore the association between fibroblast growth factor 23 (FGF23) and hearing in chronic renal failure (CRF). METHODS: Pure tone audiometry was used to detect the hearing of patients with CRF; the level of serum FGF23, creatinine, blood urea nitrogen (BUN), parathyroid hormone (PTH), and mean binaural hearing threshold were compared to the control group (people without kidney disease). The rat model of renal failure was established by 5/6 nephrectomy, and the auditory brainstem response (ABR) of rats after modeling was detected by the Tucker Davis Technologies (TDT) system; the expression level of FGF23 in the peripheral blood, renal and cochlear tissue was also detected. RESULTS: The incidence of hearing loss (HL) and serum FGF23 were higher in CRF patients than the control group; the sFGF23 was positively correlated with the mean binaural hearing threshold. Animal studies showed that the ABR threshold, creatinine, FGF23, BUN, and PTH increased after modeling; although, an increase in FGF23 was observed earlier than other indicators. The HL of rats with renal failure was significantly correlated with BUN, phosphate, PTH, sFGF23, kFGF23/ß-actin, eFGF23/ß-actin, weight, and modeling cycle. CONCLUSIONS: Both CRF patients and rat models showed high-frequency HL. FGF23 was highly expressed in the serum of HL renal failure patients and rats, as well as in the renal tissue and cochlea of renal failure rats. Therefore, FGF23 may be involved in the occurrence and development of HL caused by CRF.


Assuntos
Falência Renal Crônica , Insuficiência Renal Crônica , Insuficiência Renal , Animais , Humanos , Ratos , Actinas , Creatinina , Fatores de Crescimento de Fibroblastos , Audição , Hormônio Paratireóideo
4.
Sensors (Basel) ; 24(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38894168

RESUMO

In medical imaging, detecting tissue anomalies is vital for accurate diagnosis and effective treatment. Electrical impedance tomography (EIT) is a non-invasive technique that monitors the changes in electrical conductivity within tissues in real time. However, the current challenge lies in simply and accurately reconstructing multi-conductivity distributions. This paper introduces a layered fusion framework for EIT to enhance imaging in multi-conductivity scenarios. The method begins with pre-imaging and extracts the main object from the fuzzy image to form one layer. Then, the voltage difference in the other layer, where the local anomaly is located, is estimated. Finally, the corresponding conductivity distribution is established, and multiple layers are fused to reconstruct the multi-conductivity distribution. The simulation and experimental results demonstrate that compared to traditional methods, the proposed method significantly improves multi-conductivity separation, precise anomaly localization, and robustness without adding uncertain parameters. Notably, the proposed method has demonstrated exceptional accuracy in local anomaly detection, with positional errors as low as 1% and size errors as low as 33%, which significantly outperforms the traditional method with respective minimum errors of 9% and 228%. This method ensures a balance between the simplicity and accuracy of the algorithm. At the same time, it breaks the constraints of traditional linear methods, struggling to identify multi-conductivity distributions, thereby providing new perspectives for clinical EIT.

5.
Sensors (Basel) ; 24(2)2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38257426

RESUMO

This paper introduces a sensitivity matrix decomposition regularization (SMDR) method for electric impedance tomography (EIT). Using k-means clustering, the EIT-reconstructed image can be divided into four clusters, derived based on image features, representing posterior information. The sensitivity matrix is then decomposed into distinct work areas based on these clusters. The elimination of smooth edge effects is achieved through differentiation of the images from the decomposed sensitivity matrix and further post-processing reliant on image features. The algorithm ensures low computational complexity and avoids introducing extra parameters. Numerical simulations and experimental data verification highlight the effectiveness of SMDR. The proposed SMDR algorithm demonstrates higher accuracy and robustness compared to the typical Tikhonov regularization and the iterative penalty term-based regularization method (with an improvement of up to 0.1156 in correlation coefficient). Moreover, SMDR achieves a harmonious balance between image fidelity and sparsity, effectively addressing practical application requirements.

6.
Zhongguo Zhong Yao Za Zhi ; 49(8): 2158-2168, 2024 Apr.
Artigo em Zh | MEDLINE | ID: mdl-38812231

RESUMO

This study systematically explored the transdermal diffusion law of functional substances of Jingu Zhitong Gel(JGZTG). The transdermal diffusion research methods of JGZTG were investigated by single factor trial with the automated transdermal(dry-heat) sampling system. High performance liquid chromatography(HPLC) content determination method was established to determine the contents of ferulic acid, senkyunolide I, cinnamic acid, hydroxy-ε-xanthoxylin, hydroxy-α-xanthoxylin, and hydroxy-ß-xanthoxylin in the transdermal diffusion solution of JGZTG. The transdermal diffusion law of the components within 16 h was investigated. The results showed that the optimal transdermal diffusion method of JGZTG was as follows: Rat skin was used as the transdermal barrier; normal saline was used as the receiving medium; the dosage of JGZTG was 0.3 g, and the receiving solution was extracted by ethyl acetate. The results of transdermal diffusion showed that the release of ferulic acid, cinnamic acid, and senkyunolide I increased significantly at 0-8 h and slowed down at 8-16 h. The drug release was a synergic process of diffusion and dissolution, in which ferulic acid and cinnamic acid followed Higuchi and Ritger-Peppas equations, and liguolactone I followed Higuchi equation. The transdermal diffusion curves of hydroxy-ε-zanthoxylin, hydroxy-α-zanthoxylin, and hydroxy-ß-zanthoxylin showed continuous release within 16 h, and the drug release was skeleton dissolution. The diffusion law followed zero-order equation, first-order equation, and Ritger-Peppas equation. In clonclusion, it is a controlled release of ferulic acid, ligustrone I, cinnamic acid, hydroxy-ε-pyrroxylin, hydroxy-α-pyrroxylin, and hydroxy-ß-pyrroxylin in JGZTG, which can maintain stable blood drug concentration with 16 h, and the cumulative transmittance of each component with 12 h can reach 80% of cumulative transmittance with 24 h, which is in line with the clinical drug use law of bis in die.


Assuntos
Medicamentos de Ervas Chinesas , Absorção Cutânea , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacocinética , Medicamentos de Ervas Chinesas/administração & dosagem , Ratos , Animais , Difusão , Administração Cutânea , Pele/metabolismo , Pele/química , Géis/química , Masculino , Ratos Sprague-Dawley , Cromatografia Líquida de Alta Pressão , Cinamatos/farmacocinética , Cinamatos/análise , Cinamatos/química , Ácidos Cumáricos/farmacocinética , Ácidos Cumáricos/análise
7.
Anal Chem ; 95(27): 10405-10413, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37384819

RESUMO

Glycans are promising for disease diagnosis since glycan biosynthesis is significantly affected by disease states, and glycosylation changes are probably more pronounced than protein expression during the transformation to the diseased condition. Glycan-specific aptamers can be developed for challenging applications such as cancer targeting; however, the high flexibility of glycosidic bonds and scarcity of studies on glycan-aptamer binding mechanisms increased the difficulty of screening. In this work, the model of interactions between glycans and ssDNA aptamers synthesized based on the sequence of rRNA genes was developed. Our simulation-based approach revealed that paromomycin as a representative example of glycans is preferred to bind base-restricted stem structures of aptamers because they are more critical in stabilizing the flexible structures of glycans. Combined experiments and simulations have identified two optimal mutant aptamers. Our work would provide a potential strategy that the glycan-binding rRNA genes could act as the initial aptamer pools to accelerate aptamer screening. In addition, this in silico workflow would be potentially applied in the more extensive in vitro development and application of RNA-templated ssDNA aptamers targeting glycans.


Assuntos
Aptâmeros de Nucleotídeos , Paromomicina , DNA de Cadeia Simples , Aptâmeros de Nucleotídeos/química , Simulação por Computador , Polissacarídeos , Técnica de Seleção de Aptâmeros
8.
Langmuir ; 39(50): 18466-18475, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38054693

RESUMO

Extremely inefficient utilization of pesticides has prompted a study of low-cost, sustainable, and smart application systems. Herein, as a promising pesticide nanocarrier, hollow mesoporous organosilica nanoparticles (HMONs) were first synthesized by using inexpensive CaCO3 nanoparticles as the hollow templates. A redox/near-infrared light dual-triggered pesticide release system was further achieved via loading avermectin (AVM) into the HMONs and coating a layer of polydopamine (PDA). The as-prepared AVM@HMONs@PDA displays a favorable pesticide load capability (24.8 wt %), outstanding photothermal performance, and high adhesion to leaves. In addition, with glutathione (GSH), the AVM cumulative release from AVM@HMONs@PDA was 3.5 times higher than that without GSH. Under ultraviolet light irradiation, the half-life of AVM@HMONs@PDA was prolonged by 17.0-fold compared to that of the AVM technical. At day 21 after treatment in the insecticidal activity, the median lethal concentrations (LC50) values displayed that the toxicity of AVM@HMONs@PDA for Panonychus citri (McGregor) was enhanced 4.0-fold compared with the commercial emulsifiable concentrate. In the field trial, at day 28 after spraying, AVM@HMONs@PDA was significantly more control effective than AVM-EC in controlling the P. citri (McGregor), even at a 50% reduced dosage. Moreover, HMONs@PDA was safe for crops. This research presents a novel preparation approach for HMONs, and it also offers a promising nanoplatform for the precise release of pesticides.


Assuntos
Nanopartículas , Praguicidas , Praguicidas/toxicidade , Nanopartículas/toxicidade , Ivermectina/toxicidade , Raios Ultravioleta
9.
Ren Fail ; 45(1): 2194448, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37009975

RESUMO

OBJECTIVE: To investigate the predictive value of serum d-serine level for hearing impairment (HI) in uremic patients. METHODS: In this study, 30 uremic patients with HI and 30 with normal hearing were selected. The basic conditions, biochemical indicators, and serum serine levels of the two groups were compared to analyze the influencing factors of HI. RESULTS: The age and d-serine levels were higher in the HI group, while the l-serine level was lower than uremia in the normal hearing group. Logistic regression analysis showed that d-serine level ≥10 µM and older age increased the risk of HI. The area of the receiver operating characteristic (ROC) curve drawn by the prediction probability of HI was 0.838, indicating that age, d-serine, and l-serine had predictive diagnostic values for HI (p < .001). Among these, the ROC curve area of d-serine in predicting HI in uremic patients was 0.822 (p < .001). CONCLUSIONS: Increased d-serine and age are two risk factors for HI, while l-serine is a protective factor. d-Serine level has a predictive value for HI in uremic patients. Uremic patients are recommended hearing assessment, estimation of d-serine levels, and early intervention.


Assuntos
Perda Auditiva , Uremia , Humanos , Perda Auditiva/diagnóstico , Perda Auditiva/etiologia , Fatores de Risco , Curva ROC , Uremia/complicações , Uremia/diagnóstico , Estudos Retrospectivos
10.
Molecules ; 29(1)2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38202631

RESUMO

Lycium barbarum polysaccharide (LBP) is the main active component of Fructus Lycii, exhibiting various biological activities. This study aims to explore the protective effects of LBP on human corneal epithelial cells (HCEC) and a rat corneal injury model. Potential target points for LBP improving corneal injury repair were screened from public databases, and functional and pathway enrichment analyses of core targets were conducted using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Rat corneal alkali burns and HCEC oxidative stress injury models were established, and the results were validated through slit lamp examination, HE staining, TUNEL assay, immunofluorescence, CCK-8 assay, flow cytometry, scratch assay, and qRT-PCR methods. In the context of database retrieval, identification of 10 LBP monosaccharide components and 50 corneal injury repair-related targets was achieved. KEGG pathway analysis suggested that LBP might regulate the IL-17 and TNF signaling pathways through targets such as JUN, CASP3, and MMP9, thereby improving corneal damage. In vivo and in vitro experimental results indicated that LBP could reduce the increase of inflammation index scores (p < 0.05), inflammatory cell density (p < 0.01), TUNEL-positive cells (p < 0.01), corneal opacity scores (p < 0.01), and expression of corneal stromal fibrosis-related proteins α-SMA, FN, and COL (p < 0.01) caused by chemical damage to rat corneas. LBP inhibited oxidative stress-induced decreases in cell viability (p < 0.001) and migration healing ability (p < 0.01) in HCECs, reducing apoptosis rates (p < 0.001), ROS levels (p < 0.001), and the expression of inflammatory factors TNF-α and IL-6 (p < 0.01). qRT-PCR results demonstrated that LBP intervention decreased the mRNA levels of JUN, CASP3, and MMP9 in H2O2-induced alkaline-burned corneas and HCECs (p < 0.01).The integrated results from network pharmacology and validation experiments suggest that the inhibitory effects of LBP on apoptosis, inflammation, and fibrosis after corneal injury may be achieved through the suppression of the TNF and IL-17 signaling pathways mediated by JUN, CASP3, and MMP9.


Assuntos
Lesões da Córnea , Medicamentos de Ervas Chinesas , Interleucina-17 , Humanos , Animais , Ratos , Caspase 3 , Metaloproteinase 9 da Matriz , Peróxido de Hidrogênio , Córnea , Lesões da Córnea/tratamento farmacológico , Fibrose , Inflamação/tratamento farmacológico
11.
Neoplasma ; 69(4): 877-885, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35603951

RESUMO

Most endometrial cancers (EC) are diagnosed at an early stage with a favorable prognosis. However, for patients with advanced or recurrent disease, the chemotherapy response rate and overall survival remain poor. A novel in vitro model, tumor organoids, has important value in providing a more individualized treatment plan for tumor patients. However, the slow growth of the established EC organoid seriously hinders the application of EC organoids. Cancer-associated fibroblasts (CAFs), the main component of tumor stroma, have been reported to promote the proliferation of endometrial cancer cell lines and primary endometrial cancer cells in vivo and in vitro. Therefore, we optimized the current endometrial cancer organoid by introducing CAFs isolated from EC lesions. Here we developed long-term expandable organoids from endometrial cancer lesions, which show disease-associated traits and cancer-linked mutations. Based on the co-culture of CAFs and endometrial cancer organoids, we found that CAFs could promote the growth of endometrial cancer organoids, might by secreting factors according to the result that CAFs could also promote the growth. Our research provided a more promising model for the basic and preclinical study of endometrial cancer.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias do Endométrio , Fibroblastos Associados a Câncer/patologia , Proliferação de Células/genética , Neoplasias do Endométrio/metabolismo , Endométrio/metabolismo , Endométrio/patologia , Feminino , Fibroblastos/metabolismo , Humanos , Organoides
12.
Zhongguo Zhong Yao Za Zhi ; 47(18): 4927-4937, 2022 Sep.
Artigo em Zh | MEDLINE | ID: mdl-36164902

RESUMO

This study aims to explore the key factors influencing the processing of braised Rehmanniae Radix, optimize the processing, and determine the correlation between the components in different processed products and chroma values, which is expected to add quantitative indexes for the processing of braised Rehmanniae Radix and better control the processing. The weights of the indexes catalpol, rehmannioside D, verbascoside, isoacteoside, 5-hydroxymethylfurfural, reducing sugar, and appearance were calculated based on analytic hierarchy process(AHP) in combination with coefficient of variation, and the overall desirability(OD) was obtained. Box-Behnken design was used to explore the optimal amount of water added, time for soaking with rice wine, and steaming time in the processing of braised Rehmanniae Radix. Colorimeter was employed to determine the chroma of 17 samples and raw samples, and SPSS, Prism, and other software to investigate the correlation between the components in braised Rehmanniae Radix and the chroma values. The results showed that each factor influenced the processing, and the influence followed the order of steaming time>amount of water added>time for soaking with rice wine. The optimal processing process is as below: A total of 100 g medicinal material was added with 7 times of water, followed by soaking with rice wine for 5 h and steaming in a pot for 6 h. The correlation analysis suggested the extremely significantly positive correlation between L~* and content of catalpol, between a~* and 5-hydroxymethylfurfural content, and between b~* and catalpol content, and the extremely significantly negative correlation between L~* and the content of 5-hydroxymethylfurfural and reducing sugar, and between b~* and the content of 5-hydroxymethylfural and reducing sugar. In this experiment, response surface methodology was used to optimize the processing technology of braised Rehmanniae Radix and the optimized process was rational and feasible. The content of chemical components in braised Rehmanniae Radix was significantly correlated with the chroma. This study provided a new method for the quality evaluation of braised Rehmanniae Radix.


Assuntos
Medicamentos de Ervas Chinesas , Rehmannia , Medicamentos de Ervas Chinesas/química , Furaldeído/análogos & derivados , Glucosídeos Iridoides , Extratos Vegetais , Rehmannia/química , Açúcares , Tecnologia , Água
13.
J Cell Mol Med ; 25(9): 4220-4234, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33759344

RESUMO

Proliferative vitreoretinopathy (PVR) is a refractory vitreoretinal fibrosis disease, and epithelial-mesenchymal transition (EMT) of retinal pigment epithelial (RPE) cells is the key pathological mechanism of PVR. However, few studies focused on the role of METTL3, the dominating methyltransferase for m6A RNA modification in PVR pathogenesis. Immunofluorescence staining and qRT-PCR were used to determine the expression of METTL3 in human tissues. Lentiviral transfection was used to stably overexpress and knockdown METTL3 in ARPE-19 cells. MTT assay was employed to study the effects of METTL3 on cell proliferation. The impact of METTL3 on the EMT of ARPE-19 cells was assessed by migratory assay, morphological observation and expression of EMT markers. Intravitreal injection of cells overexpressing METTL3 was used to assess the impact of METTL3 on the establishment of the PVR model. We found that METTL3 expression was less in human PVR membranes than in the normal RPE layers. In ARPE-19 cells, total m6A abundance and the METTL3 expression were down-regulated after EMT. Additionally, METTL3 overexpression inhibited cell proliferation through inducing cell cycle arrest at G0/G1 phase. Furthermore, METTL3 overexpression weakened the capacity of TGFß1 to trigger EMT by regulating wnt/ß -catenin pathway. Oppositely, knockdown of METTL3 facilitated proliferation and EMT of ARPE-19 cells. In vivo, intravitreal injection of METTL3-overexpressing cells delayed the development of PVR compared with injection of control cells. In summary, this study suggested that METTL3 is involved in the PVR process, and METTL3 overexpression inhibits the EMT of ARPE-19 cells in vitro and suppresses the PVR process in vivo.


Assuntos
Transição Epitelial-Mesenquimal , Metiltransferases/metabolismo , Epitélio Pigmentado da Retina/patologia , Vitreorretinopatia Proliferativa/prevenção & controle , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Regulação da Expressão Gênica , Humanos , Masculino , Metiltransferases/genética , Pessoa de Meia-Idade , Prognóstico , Epitélio Pigmentado da Retina/metabolismo , Vitreorretinopatia Proliferativa/metabolismo , Vitreorretinopatia Proliferativa/patologia , Proteínas Wnt/genética , Adulto Jovem , beta Catenina/genética
14.
Planta ; 249(5): 1599-1615, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30771045

RESUMO

MAIN CONCLUSION: Alternative splicing (AS) events were identified and verified in cabbage by comparative transcriptome analysis. The corresponding markers were developed and the germplasm resources were identified. Alternative splicing (AS) is a central regulatory mechanism that greatly contributes to plant gene expression and transcriptome diversity. A large body of evidence has shown that AS complexity is relevant for plant development, evolution, complexity, and adaptation. Both insertion/deletion (InDel) and single nucleotide polymorphism (SNP) are typically co-dominant inheritance markers and have abundant polymorphisms. These have been widely used for marker-assisted selection, genetic mapping, and germplasm identification in plants. However, little is known about the molecular mechanisms underlying AS events and the development of markers including SNP and InDel from the cabbage transcriptome. In this study, three cabbage transcriptome datasets were collected and aligned to the cabbage reference genome to analyze AS events and marker development. 31,524 AS events were identified from three cabbage genotypes, accounting for 20.8% of the total cabbage genes. Alternative 3' splice site donor (A3SS) was the most frequent type of the four main AS events in cabbage. 70,475 InDels and 706,269 SNPs were identified with average frequencies of 1 InDel/6.9 kb and 1 SNP/0.7 kb, respectively. 71,942 potential SSRs were identified in 53,129 assembled unigenes with a density of 1 SSR/6.8 kb. The ratio of SNPs with synonymous/non-synonymous mutations was 1:0.65. 142 InDels and 36 SNPs were randomly selected and validated via Sanger sequencing and polymorphism was found among 66.2% of the InDels and 78.6% of the SNPs. Furthermore, 35 informative InDel markers were successfully used for genetic diversity analysis on 36 cabbage accessions. These results facilitate understanding of the molecular regulation mechanism underlying AS events in cabbage. They also provide molecular marker resource data for genetic mapping construction and germplasm identification, and facilitate the genetic improvement of cabbage via breeding.


Assuntos
Processamento Alternativo/genética , Brassica/genética , Mapeamento Cromossômico/métodos , Marcadores Genéticos/genética , Genoma de Planta/genética , Genótipo , Mutação INDEL/genética , Polimorfismo de Nucleotídeo Único/genética , Transcriptoma/genética
15.
J Nanosci Nanotechnol ; 19(5): 2723-2731, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30501772

RESUMO

Real materials have structural defects that are normally brought in during the processes of manufacturing and storage and often have a structure with abundant grains, as well as being subjected to multi-directional force conditions. The study of temperature's effect on plastic deformation mechanisms in polycrystalline materials bathed by a multi-axial force is still very rare and not clear. Therefore, we conducted very large-scale molecular dynamics simulations to study the deformation and fracture behaviour of nanostructured polycrystalline Ni under a pre-existing external tensile hydrostatic stress with various temperatures. By characterizing the deformation and fracture mechanisms at an atomic scale, our results elucidate the effect of temperature on brittle versus ductile fracture behaviour by analysing the local stresses for void nucleation and crack propagation and the associated interplays of grain boundary, dislocation/twin and void/crack activities. The lower temperature results in a more brittle fracture manner. This is because the decreasing temperatures contribute to more sources of local stress concentrators for void/crack nucleation and propagation, and suppress the plastic deformation achieved by the activities of grain boundary, twin and dislocation. Our findings shed a light on a fundamental understanding of polycrystalline Ni metals subjected to complex working environments.

16.
J Clin Lab Anal ; 33(9): e22998, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31429492

RESUMO

OBJECTIVE: The diagnostic value of circulating circular RNAs (circRNAs) has received more and more attention. However, little has been reported about their potential in the diagnosis of congenital heart diseases (CHD). In this study, we explored differential expression of circRNAs from children with CHD to evaluate their potential as clinical biomarkers. METHODS: We established a discovery cohort (four CHD cases; four matched healthy controls) and a validation cohort (40 CHD cases; 40 matched healthy controls). Microarray expression analysis was performed on the discovery set to identify candidate circRNAs. Candidates were further validated in the validation set. The diagnostic accuracy of circRNAs was determined by receiver operating characteristic (ROC) analysis. Gene ontology (GO), pathway, and network analysis were performed to predict a network of circRNA/miRNA and target mRNAs related to CHD. RESULTS: The top seven significantly differentially expressed CHD-associated circRNAs were validated by RT-PCR as follows: hsa_circRNA_004183, hsa_circRNA_079265, hsa_circRNA_105039, hsa_circRNA_404686, hsa_circRNA_101050, hsa_circRNA_100787, and hsa_circRNA_101328. Three significantly down-regulated circRNAs (hsa_circRNA_004183, hsa_circRNA_079265, and hsa_circRNA_105039) were identified with area under curve (AUC) values of 0.758, 0.809, and 0.907, respectively; the combination had an AUC of 0.965. An interaction network was constructed by 43 circRNAs, 9 miRNAs, and 29 mRNAs, which involved in heart development. CONCLUSIONS: We identified three circRNAs under-expressed in plasma from children with CHD. These circRNAs may be crucial in the development of CHD and may serve as novel non-invasive biomarkers for the diagnosis of CHD in children.


Assuntos
Cardiopatias Congênitas/sangue , Cardiopatias Congênitas/diagnóstico , RNA Circular/sangue , Adulto , Área Sob a Curva , Biomarcadores/sangue , Estudos de Casos e Controles , Criança , Regulação da Expressão Gênica , Ontologia Genética , Redes Reguladoras de Genes , Cardiopatias Congênitas/genética , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Retina ; 37(3): 585-591, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28225725

RESUMO

PURPOSE: To report the clinical characteristics of the affected and fellow eyes in patients with familial exudative vitreoretinopathy-associated rhegmatogenous retinal detachment (FEVR-RRD). METHODS: This was a retrospective observational case series. The affected and fellow eyes were given complete examinations. The age, sex, clinical features of the affected eyes, and varied abnormalities of the fellow eyes were analyzed. RESULTS: Forty-three patients with FEVR-RRD were included. The average age was 21.8 ± 10.9 years, and the males (19.9 ± 9.6) were younger than the females (28.1 ± 1.2). Retinal round holes were noted in 32 (71.1%) eyes. In addition, horseshoe retinal tears and giant retinal tears were present in 10 (22.2%) eyes and 3 (6.7%) eyes. Subretinal fibrosis was seen in 20 (44.4%) eyes, and choroidal detachment was shown in 6 (13.3%) of the eyes. A high prevalence of abnormalities was noted in the undetached fellow eyes in the peripheral retina, including vascular leakage in fundus fluorescein angiography (75.6%), lattice degeneration (53.7%), and vitreous traction (51.2%). CONCLUSION: Male patients with FEVR-RRD experience an earlier onset than females in our series. Retinal tears, even giant tears, could be responsible for FEVR-RRD. The fellow eyes of FEVR-RRD patients were characterized by predetachment changes, which need both lifelong monitoring and timely vision-saving intervention.


Assuntos
Descolamento Retiniano/patologia , Doenças Retinianas/complicações , Adolescente , Adulto , Criança , Estudos Transversais , Oftalmopatias Hereditárias , Vitreorretinopatias Exsudativas Familiares , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Retinianas/patologia , Perfurações Retinianas/patologia , Estudos Retrospectivos , Adulto Jovem
18.
Mol Vis ; 22: 917-32, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27555740

RESUMO

PURPOSE: To identify novel mutations in the frizzled 4 (FZD4) gene in patients with familial exudative vitreoretinopathy (FEVR) in southern China and to delineate the mutation-associated clinical manifestations. METHODS: Clinical data and genomic DNA were collected from 100 probands and their family members. The coding regions of FZD4 were screened for mutations with PCR and Sanger sequencing. Cosegregation analysis was used to verify suspected variants, and clinical symptoms in the probands were analyzed. RESULTS: Fourteen causative heterozygous mutations in FZD4 in 21 unrelated probands were noted, in 21.0% of the index patients (21/100). Four novel missense mutations (C45R, C45S, C53S, and C90R) and three novel deletion mutations (T326fsX356, G492fsX512, and S345_A351del) with a high possibility of pathogenicity were detected. None of these mutations were found in current online databases and 150 ethnically matched control subjects without retinopathy. The majority of the mutations in FZD4 were identified in probands with retinal folds (15/21) and ectopic macula (5/21). No mutations in FZD4 were found in probands with complete tractional retinal detachment in infancy or with mild asymptomatic FEVR in adulthood. CONCLUSIONS: Seven novel mutations found in this study have broadened the spectrum of mutations in FZD4 known to cause FEVR, providing a deeper understanding of this disease. The results show that mutations in FZD4 are associated with the phenotypes of retinal folds or ectopic macula in FEVR but might not be associated with extreme severe bilateral FEVR during infancy, at least in southern Chinese patients.


Assuntos
Povo Asiático/genética , Receptores Frizzled/genética , Mutação de Sentido Incorreto , Doenças Retinianas/genética , Deleção de Sequência , Adolescente , Adulto , Sequência de Aminoácidos , Criança , Pré-Escolar , China/epidemiologia , Análise Mutacional de DNA , Oftalmopatias Hereditárias , Vitreorretinopatias Exsudativas Familiares , Feminino , Estudos de Associação Genética , Humanos , Masculino , Linhagem , Reação em Cadeia da Polimerase , Doenças Retinianas/diagnóstico , Adulto Jovem
19.
Mol Vis ; 22: 352-61, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27122966

RESUMO

PURPOSE: To investigate the chemokine expression profiles in the aqueous humor of wet age-related macular degeneration (wet AMD) patients and to correlate their levels with clinical findings. METHODS: Undiluted aqueous humor samples (100-200 µl) were obtained from 16 wet AMD eyes and 12 control eyes. Forty chemokines were measured using a multiplex method. A 6×6 mm area of the macular region centered on the fovea was examined using spectral domain optical coherence tomography (SD-OCT). RESULTS: The detection rates were 50% or more for 15 chemokines. Compared with the control group, the aqueous humor in wet AMD patients showed a significantly higher expression of CXCL10 (p=0.004), CCL14 (p=0.002), CXCL16 (p=0.013), CXCL7 (p=0.033), and CCL22 (p=0.037), while growth-related oncogene (GRO) was significantly decreased in the wet AMD patients (p=0.001). When compared with treatment-naïve patients, the recurrent group had significant upregulation of CXCL10 (p=0.012) and CCL22 (p=0.002). CXCL16 was positively correlated with lesion size, and CCL22 was higher in patients whose OCT images showed intraretinal fluid (IRF) or hyperreflective foci (HF). CONCLUSIONS: Elevated levels of inflammation-related chemokines, including CXCL10, CCL14, CXCL16, CXCL7, and CCL22, in the aqueous humor of AMD patients may suggest a pathogenic role for inflammation. CXCL10 and CCL22 were more elevated in eyes with recurrent wet AMD than in treatment-naïve eyes. CXCL16 was positively correlated with lesion size. The increase in CCL22 was correlated with the presence of IRF or HF. These data may be of interest in the search for biomarkers associated with wet AMD and may potentially indicate different treatment strategies.


Assuntos
Humor Aquoso/metabolismo , Citocinas/metabolismo , Degeneração Macular Exsudativa/metabolismo , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/uso terapêutico , Feminino , Angiofluoresceinografia , Humanos , Injeções Intravítreas , Masculino , Pessoa de Meia-Idade , Ranibizumab/uso terapêutico , Tomografia de Coerência Óptica , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Degeneração Macular Exsudativa/diagnóstico , Degeneração Macular Exsudativa/tratamento farmacológico
20.
Ophthalmology ; 123(1): 19-25, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26477846

RESUMO

PURPOSE: The purpose of this study was to classify combined persistent fetal vasculature (PFV) on the basis of the ultrasonographic and Doppler characteristics. The potential clinical significance for both surgery design and prognosis determination was discussed. DESIGN: A cross-sectional case series. PARTICIPANTS: The eyes of 54 children diagnosed with unilateral combined PFV were evaluated using B-mode ultrasound and color Doppler imaging (CDI). METHODS: Each participant's age at first presentation, diagnosis for referral, gender, family history, and systemic or other ocular anomalies were recorded. Retinal detachment, optic nerve abnormalities, and macular dislocation were also recorded in detail according to the RetCam (Clarity Medical Systems, Pleasanton, CA), ultrasound, and Doppler findings. The PFV eyes were divided into 4 groups on the basis of the ultrasound and CDI findings. Intergroup analysis was performed. MAIN OUTCOME MEASURES: Overall and intergroup analyses of the demographic features of the children with PFV were performed. The axial length, depth of the anterior chamber, and lens thickness were compared between the affected eyes and the fellow healthy eyes among the 4 groups. RESULTS: Some 22.2%, 18.5%, 33.3%, and 25.9% of the eyes were grouped into type I ("I" shape), II ("Y" shape), III (inverted "Y" shape), and IV ("X" shape) combined PFV, respectively. The age at first presentation for type I was older than that for the other groups (P = 0.014). The axial length was reduced (P = 0.012) and the anterior chamber more shallow (P = 0.011) than in fellow healthy eyes for type IV eyes, but not for the other 3 groups. CONCLUSIONS: Ultrasound and CDI are informative screening and diagnostic tools that show characteristic flow patterns in the 4 types of combined PFV. This novel classification system provides new and important information for the diagnosis of PFV and, if validated, may play a role in guiding treatment recommendations in the future.


Assuntos
Anormalidades do Olho/classificação , Síndrome da Persistência do Padrão de Circulação Fetal/diagnóstico por imagem , Ultrassonografia Doppler em Cores/métodos , Corpo Vítreo/anormalidades , Pré-Escolar , Estudos Transversais , Anormalidades do Olho/diagnóstico por imagem , Feminino , Angiofluoresceinografia , Fundo de Olho , Humanos , Lactente , Recém-Nascido , Masculino , Síndrome da Persistência do Padrão de Circulação Fetal/patologia , Estudos Retrospectivos , Corpo Vítreo/irrigação sanguínea , Corpo Vítreo/diagnóstico por imagem
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