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1.
Sci Transl Med ; 16(732): eadc8930, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38295182

RESUMO

A major barrier to the impact of genomic diagnosis in patients with congenital malformations is the lack of understanding regarding how sequence variants contribute to disease pathogenesis and whether this information could be used to generate patient-specific therapies. Congenital diaphragmatic hernia (CDH) is among the most common and severe of all structural malformations; however, its underlying mechanisms are unclear. We identified loss-of-function sequence variants in the epigenomic regulator gene SIN3A in two patients with complex CDH. Tissue-specific deletion of Sin3a in mice resulted in defects in diaphragm development, lung hypoplasia, and pulmonary hypertension, the cardinal features of CDH and major causes of CDH-associated mortality. Loss of SIN3A in the lung mesenchyme resulted in reduced cellular differentiation, impaired cell proliferation, and increased DNA damage. Treatment of embryonic Sin3a mutant mice with anacardic acid, an inhibitor of histone acetyltransferase, reduced DNA damage, increased cell proliferation and differentiation, improved lung and pulmonary vascular development, and reduced pulmonary hypertension. These findings demonstrate that restoring the balance of histone acetylation can improve lung development in the Sin3a mouse model of CDH.


Assuntos
Hérnias Diafragmáticas Congênitas , Hipertensão Pulmonar , Humanos , Camundongos , Animais , Hipertensão Pulmonar/etiologia , Histonas , Acetilação , Hérnias Diafragmáticas Congênitas/genética , Hérnias Diafragmáticas Congênitas/complicações , Hérnias Diafragmáticas Congênitas/patologia , Pulmão/patologia
2.
Infect Dis Poverty ; 12(1): 99, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37953290

RESUMO

BACKGROUND: Respiratory infectious diseases (RIDs) remain a pressing public health concern, posing a significant threat to the well-being and lives of individuals. This study delves into the incidence of seven primary RIDs during the period 2017-2021, aiming to gain deeper insights into their epidemiological characteristics for the purpose of enhancing control and prevention strategies. METHODS: Data pertaining to seven notifiable RIDs, namely, seasonal influenza, pulmonary tuberculosis (PTB), mumps, scarlet fever, pertussis, rubella and measles, in the mainland of China between 2017 and 2021 were obtained from the National Notifiable Disease Reporting System (NNDRS). Joinpoint regression software was utilized to analyze temporal trends, while SaTScan software with a Poisson probability model was used to assess seasonal and spatial patterns. RESULTS: A total of 11,963,886 cases of the seven RIDs were reported during 2017-2021, and yielding a five-year average incidence rate of 170.73 per 100,000 individuals. Among these RIDs, seasonal influenza exhibited the highest average incidence rate (94.14 per 100,000), followed by PTB (55.52 per 100,000), mumps (15.16 per 100,000), scarlet fever (4.02 per 100,000), pertussis (1.10 per 100,000), rubella (0.59 per 100,000), and measles (0.21 per 100,000). Males experienced higher incidence rates across all seven RIDs. PTB incidence was notably elevated among farmers and individuals aged over 65, whereas the other RIDs primarily affected children and students under 15 years of age. The incidences of PTB and measles exhibited a declining trend from 2017 to 2021 (APC = -7.53%, P = 0.009; APC = -40.87%, P = 0.02), while the other five RIDs peaked in 2019. Concerning seasonal and spatial distribution, the seven RIDs displayed distinct characteristics, with variations observed for the same RIDs across different regions. The proportion of laboratory-confirmed cases fluctuated among the seven RIDs from 2017 to 2021, with measles and rubella exhibiting higher proportions and mumps and scarlet fever showing lower proportions. CONCLUSIONS: The incidence of PTB and measles demonstrated a decrease in the mainland of China between 2017 and 2021, while the remaining five RIDs reached a peak in 2019. Overall, RIDs continue to pose a significant public health challenge. Urgent action is required to bolster capacity-building efforts and enhance control and prevention strategies for RIDs, taking into account regional disparities and epidemiological nuances. With the rapid advancement of high-tech solutions, the development and effective implementation of a digital/intelligent RIDs control and prevention system are imperative to facilitate precise surveillance, early warnings, and swift responses.


Assuntos
Doenças Transmissíveis , Influenza Humana , Sarampo , Caxumba , Rubéola (Sarampo Alemão) , Escarlatina , Tuberculose Pulmonar , Coqueluche , Criança , Masculino , Humanos , Idoso , Caxumba/epidemiologia , Caxumba/prevenção & controle , Escarlatina/epidemiologia , Influenza Humana/epidemiologia , Doenças Transmissíveis/epidemiologia , Sarampo/prevenção & controle , Rubéola (Sarampo Alemão)/epidemiologia , China/epidemiologia , Incidência
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 302: 123134, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37480807

RESUMO

In this work, we reported the synthesis and characteristic luminescence of an orange-red emitting phosphor NaBa10Y5W4O30: Eu3+ for ultra-violet white light emitting diodes. The phase compound, crystalline structure and morphology are analyzed. The results indicate that a heavy doping of Eu3+ (x = 50%) is realized in NaBa10Y5-5xW4O30: xEu3+ without any impurity phase. Moreover, the optical band gap is analyzed by diffuse reflectance spectroscopy and further confirmed by density function theory (DFT). Meanwhile, the as-synthesized NaBa10Y5W4O30: Eu3+ phosphor can be efficiently pumped by strong broad-band excitation around 315 nm due to the charge transfer transition from [WO6]6- groups to Eu3+. Owing to the highly symmetric lattice environment of Eu3+ in YO6 sites, a strong orange-red emission at 596 nm with color purity of 95.34% is obtained, corresponding to the 5D0→7F1 magnetic dipole transition of Eu3+ ions. The critical concentration is obtained to be x = 15%, and the quenching mechanism is discussed to be dipole-dipole interaction. Furthermore, the temperature dependent emission behavior are analyzed, and the thermal quenching mechanism are explained by the variable temperature decay curve and configuration coordination diagram. Finally, an orange-red light emitting diode lamp is fabricated based on NaBa10Y5W4O30: 15%Eu3+ phosphor and 315 nm semiconductor chip. In summary, the results indicate that NaBa10Y5W4O30: Eu3+ phosphor has the potential to be an orange-red phosphor for white light emitting diodes.

4.
BMC Pediatr ; 23(1): 292, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37322473

RESUMO

BACKGROUND: Thrombosis is a serious condition in children and neonates. However, the risk factors for thrombosis have not been conclusively determined. This study aimed to identify the risk factors for thrombosis in children and neonates in Intensive Care Unit (ICU) through a meta-analysis to better guide clinical treatment. METHODS: A systematic search of electronic databases (PubMed, Embase, Cochrane Library, WOS, CNKI, Wanfang, VIP) was conducted to retrieve studies from creation on 23 May 2022. Data on the year of publication, study design, country of origin, number of patients/controls, ethnicity, and type of thrombus were extracted. The publication bias and heterogeneity between studies were assessed, and pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using fixed or random effects models. RESULTS: A total of 18 studies met the inclusion criteria. The incidence of thrombosis in children was 2% per year (95% CI 1%-2%, P < 0.01). Infection and sepsis (OR = 1.95, P < 0.01), CVC (OR = 3.66, [95%CL 1.78-7.51], P < 0.01), mechanical ventilation (OR = 2.1, [95%CL1.47-3.01], P < 0.01), surgery (OR = 2.25, [95%CL1.2-4.22], P < 0.01), respiratory distress (OR = 1.39, [95%CL0.42-4.63], P < 0.01), ethnicities (OR = 0.88, [95%CL 0.79-0.98], P = 0.78), gestational age (OR = 1.5, [95%CL1.34-1.68], P = 0.65)were identified as risk factors for thrombosis. CONCLUSIONS: This meta-analysis suggests that CVC, Surgery, mechanical ventilation, Infection/sepsis, gestational age, Respiratory distress, and different ethnicities are risk factors for thrombosis in children and neonates in ICU. These findings may help clinicians to identify high-risk patients and develop appropriate prevention strategies. TRIAL REGISTRATION: PROSPERO (CRD 42022333449).


Assuntos
Síndrome do Desconforto Respiratório , Trombose , Criança , Recém-Nascido , Humanos , Trombose/epidemiologia , Trombose/etiologia , Fatores de Risco , Respiração Artificial/efeitos adversos , Unidades de Terapia Intensiva , Síndrome do Desconforto Respiratório/complicações
5.
Nat Mater ; 22(7): 807-808, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37337070
6.
Sci Rep ; 13(1): 9481, 2023 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-37301857

RESUMO

This systematic review and meta-analysis examined the association between race and ethnicity and fracture risk in the United States. We identified relevant studies by searching PubMed and EMBASE for studies published from the databases' inception date to December 23, 2022. Only observational studies conducted in the US population that reported the effect size of racial-ethnic minority groups versus white people were included. Two investigators independently conducted literature searches, study selection, risk of bias assessment, and data abstraction; discrepancies were resolved by consensus or consultation of a third investigator. Twenty-five studies met the inclusion criteria, and the random-effects model was used to calculate the pooled effect size due to heterogeneity between the studies. Using white people as the reference group, we found that people of other races and ethnic groups had a significantly lower fracture risk. In Black people, the pooled relative risk (RR) was 0.46 (95% confidence interval (CI), 0.43-0.48, p < 0.0001). In Hispanics, the pooled RR was 0.66 (95% CI, 0.55-0.79, p < 0.0001). In Asian Americans, the pooled RR was 0.55 (95% CI, 0.45-0.66, p < 0.0001). In American Indians, the pooled RR was 0.80 (95% CI, 0.41-1.58, p = 0.3436). Subgroup analysis by sex in Black people revealed the strength of association was greater in men (RR = 0.57, 95% CI = 0.51-0.63, p < 0.0001) than in women (RR = 0.43, 95% CI = 0.39-0.47, p < 0.0001). Our findings suggest that people of other races and ethnic groups have a lower fracture risk than white people.


Assuntos
Etnicidade , Fraturas Ósseas , Masculino , Humanos , Feminino , Estados Unidos/epidemiologia , Grupos Minoritários , Fraturas Ósseas/epidemiologia , Grupos Raciais , Brancos
7.
Food Chem X ; 18: 100682, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37168720

RESUMO

In this study, Lactiplantibacillus plantarum ATCC14917 was used to ferment Ganoderma lucidum spore powder. Two polysaccharides were purified from unfermented (GLP) and fermented (FGLP) Ganoderma lucidum spore powder. The chemical structure and antioxidant activity of the polysaccharides were studied. Finally, the effect of GLP and FGLP on the oxidative stress regulation pathway in HepG2 cells was explored. The results showed that the main structural characteristics of Ganoderma lucidum polysaccharides remained unchanged during the fermentation. However, the average molecular weight (Mw) of Ganoderma lucidum polysaccharides decreased from 1.12 × 105 Da to 0.89 × 105 Da. Besides this, the contents of mannose, galactose, and glucuronic acid increased, while the contents of xylose and glucose were decreased. In addition, the content of uronic acid was raised, and the apparent structure was changed from smooth and hard to porous and loose. In antioxidant studies, intracellular ROS and MDA contents in the oxidative stress model were decreased, and T-AOC content was increased under GLP and FGLP intervention. In the investigation of the regulation pathway, Nrf-1 gene expression was up-regulated, and Keap1 gene expression was down-regulated under GLP and FGLP intervention. The antioxidant genes NQO1 and NO-1 expressions were increased to activate the activities of antioxidant enzymes CAT, SOD and GSH-PA to resist oxidative stress. Compared with GLP, FGLP has a stronger regulatory role in this pathway, thus showing more potent antioxidant activity. This experiment is beneficial to the further utilization of Ganoderma lucidum spore powder.

8.
Bioorg Chem ; 137: 106583, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37163810

RESUMO

Prostate cancer is the second most common cause of cancer-related deaths in men and is common in most developed countries. Androgen deprivation therapy (ADT) that uses abiraterone acetate (AA) is an effective second-line treatment for prostate cancer. However, approximately 20-40% of patients develop primary resistance to abiraterone post-treatment. In this study, we aimed to understand the molecular mechanisms underlying the development of abiraterone resistance in prostate cancer cells and the potential use of black phosphorus nanosheets (BPNS) for treating abiraterone-resistant prostate cancer. We first established abiraterone-resistant prostate cancer PC-3 cells and found that these cells have higher migration ability than normal prostate cancer cells. Using comparative transcriptomic and bioinformatics analyses between abiraterone-sensitive PC-3 and abiraterone-resistant PC-3 cells, we highlighted the differentially expressed genes (DEGs) involved in the biological processes related to prostate gland morphogenesis, drug response, immune response, angiogenesis. We further studied the therapeutic effects of BPNS. Our results show that BPNS reduced the proliferation and migration of abiraterone-resistant PC-3 cells. Bioinformatics analysis, including gene ontology, Kyoto encyclopedia of genes and genomes enrichment analysis, and ingenuity pathway analysis (IPA) of the DEGs, suggested that BPNS treatment controlled cancer cell proliferation, metastasis, and oncogenic signaling pathways. Furthermore, the IPA gene network highlighted the involvement of the MMP family, ATF, and notch families in the anti-prostate cancer function of BPNS. Our findings suggest that BPNS may have a chemotherapeutic function in treating abiraterone-resistant prostate cancer.


Assuntos
Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Antagonistas de Androgênios , Fosfatos/uso terapêutico , Resultado do Tratamento , Doxorrubicina , Perfilação da Expressão Gênica
9.
Plants (Basel) ; 12(3)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36771715

RESUMO

Paris polyphylla var. yunnanensis, a medicinal plant that originated in Yunnan (China), has been over-harvested in the wild population, resulting in its artificial cultivation. Given the negative environmental impacts of the excessive use of phosphorus (P) fertilization, the application of organophosphate-degrading bacteria (OPDB) is a sustainable approach for improving the P use efficiency in Paris polyphylla var. yunnanensis production. The present work aimed to analyze the effects of three organic phosphate-solubilizing bacteria of Bacillus on the yield and quality of P. polyphylla var. yunnanensis and the P concentrations in the soil. All the inoculation treatments distinctly increased the rhizome biomass, steroidal, and total saponin concentrations of the rhizomes and the Olsen-P and organic P in the soil. The highest growth rate of rhizomes biomass, steroidal saponins, available phosphorus, and total phosphorus content was seen in the S7 group, which was inoculated with all three OPDB strains, showing increases of 134.58%, 132.56%, 51.64%, and 17.19%, respectively. The highest total saponin content was found in the group inoculated with B. mycoides and B. wiedmannii, which increased by 33.68%. Moreover, the highest organic P content was seen in the group inoculated with B. wiedmannii and B. proteolyticus, which increased by 96.20%. In addition, the rhizome biomass was significantly positively correlated with the saponin concentration, together with the positive correlation between the Olsen-P and organic P and total P. It is concluded that inoculation with organophosphate-degrading bacteria improved the biomass and medicinal ingredients of the rhizome in P. polyphylla var. yunnanensis, coupled with increased soil P fertility, with a mixture of the three bacteria performing best.

10.
Food Res Int ; 161: 111866, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36192906

RESUMO

Soybean paste is a tradition of fermented soybean paste products under natural conditions. This study used high-throughput sequencing and headspace-solid phase microextraction combined with gas chromatography-mass spectrometry to determine soybean paste's microbial communities and volatile components at different storage periods. Data analysis determined the key flora and their effects on flavor substances. The results showed that acids, phenols and pyrazines contributed the most to the flavor of soybean sauce in different storage periods. Mucor, Bacillus, Lactobacillus, Candida, Kroppenstedtia and Clostridium_sensu_stricto_12 played a vital role in the key flavor components. This study revealed a significant relationship between soybean paste flavour and colonies in different storage periods.


Assuntos
Microbiota , Alimentos de Soja , Fenóis/análise , Pirazinas , Alimentos de Soja/análise , /química
11.
Nanomicro Lett ; 14(1): 175, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35999406

RESUMO

4-tert-butylpyridine (TBP) is an indispensable additive for the hole transport layer in highly efficient perovskite solar cells (PSCs), while it can induce corrosion decomposition of perovskites and de-doping effect of spiro-OMeTAD, which present huge challenge for the stability of PSCs. Herein, halogen bonds provided by 1,4-diiodotetrafluorobenzene (1,4-DITFB) are employed to bond with TBP, simultaneously preventing perovskite decomposition and eliminating de-doping effect of oxidized spiro-OMeTAD. Various characterizations have proved strong chemical interaction forms between 1,4-DITFB and TBP. With the incorporation of halogen bonds, perovskite film can maintain initial morphology, crystal structure, and light absorbance; meanwhile, the spiro-OMeTAD film shows a relatively stable conductivity with good charge transport property. Accordingly, the device with TBP complex exhibits significantly enhanced stability in N2 atmosphere or humidity environment. Furthermore, a champion power conversion efficiency of 23.03% is obtained since perovskite is no longer damaged by TBP during device preparation. This strategy overcomes the shortcomings of TBP in n-i-p PSCs community and enhances the application potential of spiro-OMeTAD in fabricating efficient and stable PSCs.

12.
Mitochondrial DNA B Resour ; 7(8): 1445-1447, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35965647

RESUMO

Mallotus paniculatus (Lam.) Müll. Arg. 1865 (Euphorbiaceae) is a shrub or small tree with medicinal properties that is distributed across Southeast Asia. In this study, we sequenced the complete chloroplast genome of M. paniculatus to study phylogenetic relationships within the family Euphorbiaceae Juss. The complete chloroplast genome of M. paniculatus was 164,455 bp in length, with an overall GC content of 35.3%. It was found to consist of a long single copy region of 89,021 bp, a small single copy region of 18,524 bp, and a pair of inverted repeats of 28,455 bp. Results indicated that the chloroplast genome contains a total of 131 genes, including 78 protein-coding genes, 37 tRNA genes, eight rRNA genes, and eight pseudogenes. The phylogenetic tree showed that M. paniculatus is closely related to Mallotus japonicus and Mallotus peltatus.

13.
IEEE Trans Med Imaging ; 41(11): 3398-3410, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35767510

RESUMO

Medical image segmentation is fundamental and essential for the analysis of medical images. Although prevalent success has been achieved by convolutional neural networks (CNN), challenges are encountered in the domain of medical image analysis by two aspects: 1) lack of discriminative features to handle similar textures of distinct structures and 2) lack of selective features for potential blurred boundaries in medical images. In this paper, we extend the concept of contrastive learning (CL) to the segmentation task to learn more discriminative representation. Specifically, we propose a novel patch-dragsaw contrastive regularization (PDCR) to perform patch-level tugging and repulsing. In addition, a new structure, namely uncertainty-aware feature re- weighting block (UAFR), is designed to address the potential high uncertainty regions in the feature maps and serves as a better feature re- weighting. Our proposed method achieves state-of-the-art results across 8 public datasets from 6 domains. Besides, the method also demonstrates robustness in the limited-data scenario. The code is publicly available at https://github.com/lzh19961031/PDCR_UAFR-MIShttps://github.com/lzh19961031/PDCR_UAFR-MIS.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Processamento de Imagem Assistida por Computador/métodos
14.
J Colloid Interface Sci ; 625: 297-304, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35717845

RESUMO

Dual-color or multispectral imaging based on conventional optical imaging techniques is suffering from the bottleneck of complex manufacturing and time consumption caused by multiple imaging. Herein, we develop a dual-color computational imaging system combining a vertically stacked dual-channel dual-band perovskite photodetectors (PDs) and the advanced Fourier imaging algorithm. Significantly, our imaging system bypasses the complex fabrication process of high-density dual-band PD arrays and is enabled to capture two high-resolution spectral images at the same time. Based on the experiments and simulations, we confirm that the spectral overlap of dual-band PDs will cause detrimental effect for color identification, and optimizing the bandwidth spectrum is beneficial for achieving much better spectral imaging. Moreover, we have further improved the imaging quality by increasing the sampling rate and suppressing current fluctuations. We suggest that these results provide important interesting insights for the development of advanced imaging systems, including IR imaging, THz imaging, multispectral/hyperspectral imaging, etc.


Assuntos
Algoritmos , Diagnóstico por Imagem , Compostos de Cálcio , Óxidos , Titânio
15.
J Exp Bot ; 73(7): 2077-2092, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-34849730

RESUMO

ABA-INSENSITIVE 3 (ABI3) has long been known for activation of storage protein accumulation. A role of ABI3 on oil accumulation was previously suggested based on a decrease of oil content in seeds of abi3 mutant. However, this conclusion could not exclude possibilities of indirect or pleiotropic effects, such as through mutual regulatory interactions with FUSCA3 (FUS3), an activator of oil accumulation. To identify that ABI3 functions independent of the effects of related seed transcription factors, we expressed ABI3 under the control of an inducible promoter in tobacco BY2 cells and Arabidopsis rosette leaves. Inducible expression of ABI3 activated oil accumulation in these non-seed cells, demonstrating a general role of ABI3 in regulation of oil biosynthesis. Further expressing ABI3 in rosette leaves of fus3 knockout mutant still caused up to 3-fold greater triacylglycerol accumulation, indicating ABI3 can activate lipid accumulation independently of FUS3. Transcriptome analysis revealed that LIPID DROPLET PROTEIN (LDP) genes, including OLEOSINs and CALEOSINs, were up-regulated up to 1000-fold by ABI3 in the absence of FUS3, while the expression of WRINKLED1 was doubled. Taken together, our results provide genetic evidence that ABI3 activates oil accumulation with or without FUS3, most likely through up-regulating LDPs and WRINKLED1.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Proteínas Associadas a Gotículas Lipídicas/genética , Proteínas Associadas a Gotículas Lipídicas/metabolismo , Sementes/metabolismo , Fatores de Transcrição/genética
16.
IEEE Trans Med Imaging ; 40(10): 2629-2641, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33471751

RESUMO

Automatic and accurate 3D cardiac image segmentation plays a crucial role in cardiac disease diagnosis and treatment. Even though CNN based techniques have achieved great success in medical image segmentation, the expensive annotation, large memory consumption, and insufficient generalization ability still pose challenges to their application in clinical practice, especially in the case of 3D segmentation from high-resolution and large-dimension volumetric imaging. In this paper, we propose a few-shot learning framework by combining ideas of semi-supervised learning and self-training for whole heart segmentation and achieve promising accuracy with a Dice score of 0.890 and a Hausdorff distance of 18.539 mm with only four labeled data for training. When more labeled data provided, the model can generalize better across institutions. The key to success lies in the selection and evolution of high-quality pseudo labels in cascaded learning. A shape-constrained network is built to assess the quality of pseudo labels, and the self-training stages with alternative global-local perspectives are employed to improve the pseudo labels. We evaluate our method on the CTA dataset of the MM-WHS 2017 Challenge and a larger multi-center dataset. In the experiments, our method outperforms the state-of-the-art methods significantly and has great generalization ability on the unseen data. We also demonstrate, by a study of two 4D (3D+T) CTA data, the potential of our method to be applied in clinical practice.


Assuntos
Processamento de Imagem Assistida por Computador , Aprendizado de Máquina Supervisionado , Coração/diagnóstico por imagem , Imageamento Tridimensional
17.
Tree Physiol ; 41(2): 331-342, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33032322

RESUMO

Nervonic acid (24:1) is a major component in nerve and brain tissues and it has important applications in food and pharmaceutical industries. Malania oleifera seeds contain about 40% nervonic acid. However, the mechanism of nervonic acid biosynthesis and accumulation in seeds of this endangered tree species remains unknown. In this study, developmental changes in fatty acid composition within embryos and their pericarps were investigated. Nervonic acid proportions steadily increased in developing embryos but 24:1 was not detected in pericarps at any stage. Two 3-ketoacyl-CoA synthase (KCS) homologs have been isolated from M. oleifera developing seeds by homologous cloning methods. Both KCSs are expressed in developing embryos but not detected in pericarps. Based on a phylogenetic analysis, these two KCSs were named as MoKCS4 and MoKCS11. Seed-specific expression of the MoKCS11 in Arabidopsis thaliana led to about 5% nervonic acid accumulation, while expression of the MoKCS4 did not show an obvious change in fatty acid composition. It is noteworthy that the transformation of the same MoKCS11 construct into two Brassica napus cultivars with high erucic acid did not produce the expected accumulation of nervonic acid, although expression of MoKCS11 was detected in the developing embryos of transgenic lines. In contrast, overexpression of MoKCS11 results in similar level of nervonic acid accumulation in camelina, a species which contains a similar level of 11Z-eicosenoic acid as does Arabidopsis thaliana. Taken together, the MoKCS11 may have a substrate preference for 11Z-eicosenoic acid, but not for erucic acid, in planta.


Assuntos
Ácidos Graxos , Sementes , Coenzima A , Ácidos Graxos Monoinsaturados , Filogenia , Plantas Geneticamente Modificadas/genética , Sementes/genética
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 248: 119181, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33257245

RESUMO

White light emission phosphors are widely researched for application in lighting and display fields. However, the poor thermal stability is a real problem for the known single-phased white phosphors, which limits their further application. In this paper, Ca19Na2Mg(PO4)14: xDy3+, yTm3+ (CNMP, 0 ≤ x ≤ 0.06, y = 0, 0.01) phosphors with adjustable emission and good thermal stability are synthesized. The X-ray diffraction and X-ray energy dispersive spectrometer measurement distinctly confirm the successful synthesis of CNMP: xDy3+, yTm3+ (CNMP, 0 ≤ x ≤ 0.06, y = 0, 0.01). The photoluminescence results reveal that CNMP: Dy3+ shows characteristic excitation peaks in the range of 350-450 nm, and mainly exhibits strong yellow emission around 575 nm ascribed to the 4F9/2-6H13/2 transitions of Dy3+. To compensate the deficiency of blue light emission of CNMP: Dy3+, the trivalent Tm3+ ion is co-doped owing to its characteristic blue emission at 450 nm due to its 1D2-3F4 transitions. Therefore, the emission of CNMP: Dy3+, Tm3+ can be tuned from blue light region with CIE coordinates of (0.1649, 0.0387) to white light region with CIE coordinates of (0.3001, 0.3003) and finally move to yellow light region with CIE coordinates of (0.3732, 0.4493) through adjusting the doping ratio of Dy3+/Tm3+. The energy transfer efficiency and the energy transfer mechanism from Tm3+ to Dy3+ are further investigated. Moreover, CNMP: Dy3+, Tm3+ exhibites a high thermal stability and the emission intensity still keeps 84% of the initial intensity of Dy3+ at 230 °C. These outstanding properties show that Ca19Na2Mg(PO4)14: Dy3+, Tm3+ have great advantages and potentiality for applying in solid state lighting.

19.
Mol Ther Nucleic Acids ; 18: 851-862, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31739210

RESUMO

Deletion and mutation of the Smad4 gene are favorable events for the progression of colon cancer, which is related to the negative regulation of vascular endothelial growth factor C (VEGF-C). However, the regulatory mechanism between Smad4 and VEGF-C remains unclear. We reported first that Smad4 can increase the transcription of miR-128-3p, a microRNA targeting VEGF-C mRNA, resulting in a negative correlation between Smad4 and VEGF-C. Moreover, we found that Smad4 combined with Smad3 can positively regulate VEGF-C during colon cancer metastasis through binding to VEGF-C gene promoter. Further, results revealed a mechanism that long noncoding RNA (lncRNA) ASLNC07322 increased specifically in metastatic colon cancer and decreased miR-128-3p as a sponge, leading to a subsequent elevation of VEGF-C. In a word, there are two pathways in the progression of colon cancer, including Smad4/miR-128-3p/VEGF-C and Smad4/VEGF-C pathways in non-metastatic and metastatic colon cancer, respectively. ASLNC07322 crucially controlled this negative and positive regulatory transformation between them. Additionally, ASLNC07322 knockdown combined with Smad4 overexpression could efficiently inhibit lymphatic endothelial cells (LECs) proliferation and tube formation in vitro, as well as tumor growth and lymphangiogenesis in vivo. These data explained the underlying mechanism of Smad4 contribution on VEGF-C expression during metastasis where ASLNC07322 functions vitally as a switch in colon cancer.

20.
Dalton Trans ; 48(5): 1624-1632, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30516205

RESUMO

To research and develop potential phosphors for ultraviolet-based white light emitting diodes, a novel red emission phosphate phosphor Ca18Li3Bi1-xEux(PO4)14 was synthesized and investigated in the full range of 0 ≤x≤ 1. The phase purity and crystal structure of the solid solution phosphors were investigated in detail by employing X-ray diffractometer structure refinement, scanning electron microscopy and energy dispersive spectrometry. The crystal structure information was confirmed and the structure as well as the doping concentration dependent characteristic photoluminescence properties were discussed in detail. The results indicated that high Eu3+ doping content x could be realized in Ca18Li3Bi1-xEux(PO4)14 solid solutions even when x = 1. The luminescence performance revealed that Ca18Li3Bi1-xEux(PO4)14 phosphors could emit intense red emission under 394 nm excitation with excellent CIE chromaticity coordinates and high color purity. The concentration dependent emission decay behavior at room temperature and the temperature dependent decay behavior were studied to investigate the luminescent dynamics. The abnormal thermal quenching behavior was investigated via the temperature dependent emission. The related mechanism was discussed through thermoluminescence analysis, charge compensation contrast test and the cooling emission curve measurement, and the thermal activation energy was studied. The above results indicated that the Ca18Li3Bi1-xEux(PO4)14 could be a promising red-emitting phosphor for white light emitting diodes.

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