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1.
J Am Chem Soc ; 146(4): 2514-2523, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38247135

RESUMO

Precise mapping and regulation of cell surface receptors hold immense significance in disease treatment, such as cancer, infection, and neurodisorders, but also face enormous challenges. In this study, we designed a series of adjustable multivalent aptamer-based DNA nanostructures to precisely control their interaction with receptors in tumor cells. By profiling surface receptors on 12 cell lines using 10 different aptamers, we generated a heatmap that accurately distinguished between various tumor types based on multiple markers. We then incorporated these aptamers onto DNA origami structures to regulate receptor recognition, with patch-like structures demonstrating a tendency to be trapped on the cell surface and with tube-like structures showing a preference for internalization. Through precise control of aptamer species, valence, and geometric patterns, we found that multiheteroreceptor-mediated recognition not only favored the specific binding of nanostructures to tumor cells but also greatly enhanced intracellular uptake by promoting clathrin-dependent endocytosis. Specifically, we achieved over 5-fold uptake in different tumor cells versus normal cells using tube-like structures modified with different diheteroaptamer pairs, facilitating targeted drug delivery. Moreover, patch-like structures with triheteroaptamers guided specific interactions between macrophages and tumor cells, leading to effective immune clearance. This programmable multivalent system allows for the precise regulation of cell recognition using multiple parameters, demonstrating great potential for personalized tumor treatment.


Assuntos
Aptâmeros de Nucleotídeos , Nanoestruturas , Neoplasias , Humanos , Aptâmeros de Nucleotídeos/química , Neoplasias/tratamento farmacológico , Nanoestruturas/química , Sistemas de Liberação de Medicamentos , DNA/química , Linhagem Celular Tumoral
2.
Small ; : e2400238, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38385800

RESUMO

The performance of Stimulated Emission Depletion (STED) microscopy depends critically on the fluorescent probe. Ultrasmall Au nanoclusters (Au NCs) exhibit large Stokes shift, and good stimulated emission response, which are potentially useful for STED imaging. However, Au NCs are polydispersed in size, sensitive to the surrounding environment, and difficult to control surface functional group stoichiometry, which results in reduced density and high heterogeneity in the labeling of biological structures. Here, this limitation is overcome by developing a method to encapsulate ultrasmall Au NCs with DNA cages, which yielded monodispersed, and monofunctionalized Au NCs that are long-term stable. Moreover, the DNA-caging also greatly improved the fluorescence quantum yield and photostability of Au NCs. In STED imaging, the DNA-caged Au NCs yielded ≈40 nm spatial resolution and are able to resolve microtubule line shapes with good labeling density and homogeneity. In contrast, without caging, the Au NCs-DNA conjugates only achieved ≈55 nm resolution and yielded spotted, poorly resolved microtubule structures, due to the presence of aggregates. Overall, a method is developed to achieve precise surface functionalization and greatly improve the monodispersity, stability, as well as optical properties of Au NCs, providing a promising class of fluorescent probes for STED imaging.

3.
Int J Legal Med ; 138(2): 361-373, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37843624

RESUMO

The GA118-24B Genetic Analyzer (hereafter, "GA118-24B") is an independently developed capillary electrophoresis instrument. In the present research, we designed a series of validation experiments to test its performance at detecting DNA fragments compared to the Applied Biosystems 3500 Genetic Analyzer (hereafter, "3500"). Three commercially available autosomal short tandem repeat multiplex kits were used in this validation. The results showed that GA118-24B had acceptable spectral calibration for three kits. The results of accuracy and concordance studies were also satisfactory. GA118-24B showed excellent precision, with a standard deviation of less than 0.1 bp. Sensitivity and mixture studies indicated that GA118-24B could detect low-template DNA and complex mixtures as well as the results generated by 3500 in parallel experiments. Based on the experimental results, we set specific analytical and stochastic thresholds. Besides, GA118-24B showed superiority than 3500 within certain size ranges in the resolution study. Instead of conventional commercial multiplex kits, GA118-24B performed stably on a self-developed eight-dye multiplex system, which were not performed on 3500 Genetic Analyzer. We compared our validation results with those of previous research and found our results to be convincing. Overall, we conclude that GA118-24B is a stable and reliable genetic analyzer for forensic DNA identification.


Assuntos
Impressões Digitais de DNA , DNA , Humanos , Impressões Digitais de DNA/métodos , Reação em Cadeia da Polimerase/métodos , Repetições de Microssatélites , Eletroforese Capilar/métodos
4.
Plant Dis ; 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38853337

RESUMO

Wheat (Triticum aestivum L.) is one of the most important crops worldwide. Powdery mildew caused by Blumeria graminis f. sp. tritici (Bgt) is a destructive disease threatening wheat yield and quality. The utilization of resistant genes and cultivars is considered the most economical, environmentally-friendly, and effective method to control powdery mildew. Wheat breeding line Jingzi 102 was highly resistant to powdery mildew at both seedling and adult plant stages. Genetic analysis of F1, F2, and F2:3 populations of "Jingzi 102 × Shixin 828" showed that the resistance of Jingzi 102 against powdery mildew isolate E09 at the seedling stage was controlled by a single dominant gene, temporarily designated PmJZ. Using bulked segregant RNA-Seq combined with molecular markers analysis, PmJZ was located on the long arm of chromosome 2B and flanked by markers BJK695-1 and CIT02g-20 with the genetic distances of 1.2 and 0.5 cM, respectively, corresponding to the bread wheat genome of Chinese Spring (IWGSC RefSeq v2.1) 703.8-707.6 Mb. PmJZ is most likely different from the documented Pm genes on chromosome 2BL based on their physical positions, molecular markers analysis, and resistance spectrum. Based on the gene annotation information, five genes related to disease resistance could be considered as the candidate genes of PmJZ. To accelerate the application of PmJZ, the flanking markers BJK695-1 and CIT02g-20 can serve for marker-assisted selection of PmJZ in wheat disease resistance breeding.

5.
Chem Res Chin Univ ; 39(1): 42-60, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36687211

RESUMO

The development of stimuli-responsive nanodevices with high efficiency and specificity is very important in biosensing, drug delivery, and so on. DNAzymes are a class of DNA molecules with the specific catalytic activity. Owing to their unique catalytic activity and easy design and synthesis, the construction and application of DNAzymes-based nanodevices have attracted much attention in recent years. In this review, the classification and properties of DNAzyme are first introduced. The construction of several common kinds of DNAzyme-based nanodevices, such as DNA motors, signal amplifiers, and logic gates, is then systematically summarized. We also introduce the application of DNAzyme-based nanodevices in sensing and therapeutic fields. In addition, current limitations and future directions are discussed.

6.
Angew Chem Int Ed Engl ; 62(23): e202302525, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-36930411

RESUMO

Carbon monoxide (CO) is an endogenous signaling molecule with broad therapeutic effects. Here, a multifunctional X-ray-triggered carbon monoxide (CO) and manganese dioxide (MnO2 ) generation nanoplatform based on metal carbonyl and scintillating nanoparticles (SCNPs) is reported. Attributed to the radioluminescent characteristic of SCNPs, UV-responsive Mn2 (CO)10 is not only indirectly activated to release CO by X-ray but can also be degraded into MnO2 . A high dose of CO can be used as a glycolytic inhibitor for tumor suppression; it will also sensitize tumor cells to radiotherapy. Meanwhile MnO2 , as the photolytic byproduct of Mn2 (CO)10 , has both glutathione (GSH) depletion and Fenton-like Mn2+ delivery properties to produce highly toxic hydroxyl radical (⋅OH) in tumors. Thus, this strategy can realize X-ray-activated CO release, GSH depletion, and ⋅OH generation for cascade cancer radiosensitization. Furthermore, X-ray-activated Mn2+ in vivo demonstrates an MRI contrast effect, making it a potential theranostic nanoplatform.


Assuntos
Nanopartículas , Neoplasias , Humanos , Compostos de Manganês/farmacologia , Compostos de Manganês/uso terapêutico , Óxidos/farmacologia , Monóxido de Carbono/farmacologia , Monóxido de Carbono/uso terapêutico , Raios X , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Linhagem Celular Tumoral , Glutationa/metabolismo , Peróxido de Hidrogênio/uso terapêutico
7.
J Biol Chem ; 295(41): 14140-14152, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-32690611

RESUMO

Transcriptional repressor zinc finger and BTB domain containing 1 (ZBTB1) is required for DNA repair. Because DNA repair defects often underlie genome instability and tumorigenesis, we determined to study the role of ZBTB1 in cancer. In this study, we found that ZBTB1 is down-regulated in breast cancer and this down-regulation is associated with poor outcome of breast cancer patients. ZBTB1 suppresses breast cancer cell proliferation and tumor growth. The majority of breast cancers are estrogen receptor (ER) positive and selective estrogen receptor modulators such as tamoxifen have been widely used in the treatment of these patients. Unfortunately, many patients develop resistance to endocrine therapy. Tamoxifen-resistant cancer cells often exhibit higher HER2 expression and an increase of glycolysis. Our data revealed that ZBTB1 plays a critical role in tamoxifen resistance in vitro and in vivo To see if ZBTB1 regulates HER2 expression, we tested the recruitments of ZBTB1 on HER2 regulatory sequences. We observed that over-expressed ZBTB1 occupies the estrogen receptor α (ERα)-binding site of the HER2 intron in tamoxifen-resistant cells, suppressing tamoxifen-induced transcription. In an effort to identify potential microRNAs (miRNAs) regulating ZBTB1, we found that miR-23b-3p directly targets ZBTB1. MiR-23b-3p regulates HER2 expression and tamoxifen resistance via targeting ZBTB1. Finally, we found that miR-23b-3p/ZBTB1 regulates aerobic glycolysis in tamoxifen-resistant cells. Together, our data demonstrate that ZBTB1 is a tumor suppressor in breast cancer cells and that targeting the miR-23b-3p/ZBTB1 may serve as a potential therapeutic approach for the treatment of tamoxifen resistant breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Receptor ErbB-2/biossíntese , Proteínas Repressoras/metabolismo , Tamoxifeno/farmacologia , Proteínas Supressoras de Tumor/metabolismo , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Glicólise/genética , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , Receptor ErbB-2/genética , Proteínas Repressoras/genética , Proteínas Supressoras de Tumor/genética
8.
Anal Chem ; 93(11): 4967-4974, 2021 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-33703873

RESUMO

Taking advantage of the excellent trans-cleavage activity, CRISPR-based diagnostics (CRISPR-Dx) has shown great promise in molecular diagnostics. However, the single-stranded DNA reporter of the current CRISPR-Dx suffers from poor stability and limited sensitivity, which make their application in complex biological environments difficult. Herein, we, for the first time, explore the trans-cleavage activity of CRISPR/Cas12a toward the substrate on gold nanoparticles and apply the new phenomenon to develop a spherical nucleic acid (SNA) reporter for stable and sensitive CRISPR-Dx biosensing. By anchoring the DNA substrate on gold nanoparticles, we discovered different trans-cleavage activities of different types of the Cas12a system (e.g., LbCas12a and AsCas12a) on a nanoparticle surface. The further study suggests that the trans-cleavage activity of LbCas12a on the nanoparticle surface is highly dependent on the density and length of DNA strands. Based on these interesting discoveries, we furthermore develop SNA reporter-based fluorescent CRISPR-Dx for stable and sensitive biosensing application. Compared to traditional ssDNA reporters, the SNA reporter exhibits improved stability, which enables the stable application in a complex serum environment. In addition, the SNA reporter system with tunable density exhibits high sensitivity with a detection limit of 10 fM, which is about 2 orders of magnitude lower than that of the ssDNA reporter system. Finally, the practical application of SNA reporter-based CRISPR-Dx in clinical serum was successfully achieved. These results indicate their significant potential in future research on biology science and medical diagnoses.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Nanopartículas Metálicas , Sistemas CRISPR-Cas/genética , DNA de Cadeia Simples/genética , Ouro
9.
Plant Dis ; 105(12): 3900-3908, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34129353

RESUMO

Powdery mildew and leaf rust, caused by Blumeria graminis f. sp. tritici and Puccinia triticina, respectively, are widespread diseases of wheat worldwide. The use of resistant cultivars is considered the most economical, environment-friendly, and effective method to control these diseases. In the present study, a collection of 2,978 wheat accessions consisting of 1,394 advanced breeding lines, 1,078 Chinese cultivars, 291 introduced cultivars, 132 lines containing alien chromosomes, and 83 landraces was tested for reactions to powdery mildew and leaf rust. The results indicated that 659 wheat accessions (22.1%) were highly resistant to a widely prevalent B. graminis f. sp. tritici isolate, E09, at the seedling stage, and 390 were consistently resistant to the mixture of B. graminis f. sp. tritici isolates at the adult plant stage. Meanwhile, 63 accessions (2.1%) were highly resistant to leaf rust at the adult plant stage, of which 54 were resistant to a predominant and highly virulent P. triticina race, THTT, at the seedling stage. Notably, 17 accessions were resistant to both powdery mildew and leaf rust. To detect known genes for resistance to powdery mildew and leaf rust, these accessions were tested with gene-specific or tightly linked markers for seven powdery mildew genes (Pm genes; Pm2, Pm4, Pm5, Pm6, Pm8, Pm21, and Pm24) and 10 Lr genes (Lr1, Lr9, Lr10, Lr19, Lr20, Lr24, Lr26, Lr34, Lr37, and Lr46). Of the 659 powdery mildew-resistant accessions, 328 might carry single Pm genes and 191 carry combined Pm genes. Pm2 was detected at the highest frequency of 59.6%, followed by Pm8, Pm6, Pm21, Pm4, and Pm5, whereas Pm24 was not detected. In addition, 139 accessions might contain unknown Pm genes different from those tested in this study. In the 63 accessions resistant to leaf rust, four leaf rust genes (Lr genes; Lr1, Lr10, Lr26, and Lr34) were detected in 41 accessions singly or in combination, whereas six genes (Lr9, Lr19, Lr20, Lr24, Lr37, and Lr46) were not detected. Twenty-two accessions might contain unknown Lr genes different from those tested in this study. This study not only provided important information for rationally distributing resistance genes in wheat breeding programs, but also identified resistant germplasm that might have novel genes to enrich the diversity of resistance sources.


Assuntos
Basidiomycota , Triticum , Genes de Plantas , Melhoramento Vegetal , Doenças das Plantas/genética , Triticum/genética
10.
Anal Chem ; 91(17): 11374-11379, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31402646

RESUMO

Spherical nucleic acids (SNAs) play critical roles in many fields, such as molecular diagnostics, disease therapeutics, and materials application. Due to the important role of DNA density on the properties of SNAs, the controlled synthesis of monodisperse SNAs with precise DNA density is an important approach for the structure-function relationship study and finite functions regulation of SNAs. In particular, the construction of monodisperse SNAs in a valency-tunable and site-specific manner is highly important; however, it is still challenging. Herein, on the basis of the high controllability, nanometer precision, and addressable modification ability of framework nucleic acid (FNA), we develop the concept of valency-controlled framework nucleic acid core-based molecular spherical nucleic acids (FNA-mSNAs) with tunable biosensing performances. The FNA-mSNAs consist of a valency-tunable FNA-based DNA nanocube as the core and a controlled, precise number of DNA strands per core. By simply alternating the binding site number for shell DNA strands on the DNA nanocube, homogeneous FNA-mSNAs with different valencies were easily designed, which enabled the molecular level study of the effect of valency on their properties, such as nuclease stability and cellular uptake. Furthermore, taking advantage of the addressable modification ability of FNA, the first heterogeneous molecular SNAs with tunable valency were demonstrated. Importantly, the valency of heterogeneous FNA-mSNAs was able to tune their biosensing performance, such as response dynamics, detection sensitivity, and response range. With these remarkable features, FNA-mSNAs provide new research methods for the development of functional SNAs at the molecular level for a wide range of biological applications.


Assuntos
Técnicas Biossensoriais/métodos , Nanotecnologia/métodos , Ácidos Nucleicos/química , Sítios de Ligação , DNA , Conformação de Ácido Nucleico
11.
Mol Genet Genomics ; 294(2): 493-500, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30604070

RESUMO

Congenital anomalies of the kidney and urinary tract (CAKUT) are a wide range of congenital structural renal defects. CAKUT is the leading cause of chronic renal failure and end-stage renal disease in children. Studies in humans and animal models have confirmed the large genetic contribution to CAKUT. The previous evidence suggested that human TBX6 coding mutations might cause CAKUT via gene-dosage insufficiency. However, the potential involvement of TBX6 noncoding mutations in CAKUT remains to be elucidated. Here, we described DNA sequencing and copy-number analysis of TBX6 in 269 Chinese subjects with CAKUT. Interestingly, we identified two heterozygous noncoding variants of TBX6 in sporadic subjects with CAKUT: one is c.769-7delT, from a subject with duplex renal and collecting system, and the other is a 3' untranslated region (3'-UTR) variant (c.1392C>T) from a subject with unilateral renal hypoplasia. These two TBX6 noncoding variants are novel and extremely rare, respectively, in human populations archived in the ExAC database. The mini-gene splicing assay showed that the TBX6 c.769-7delT variant significantly reduced the splicing efficiency of TBX6 intron 5 when compared to the wild-type control. In this work, we identified a novel splicing variant of TBX6 in human CAKUT. Our experimental observations suggested that the TBX6 noncoding variant can affect gene expression and may potentially be involved in human CAKUT.


Assuntos
Sítios de Splice de RNA/genética , Análise de Sequência de DNA , Proteínas com Domínio T/genética , Anormalidades Urogenitais/genética , Refluxo Vesicoureteral/genética , Adolescente , Criança , Feminino , Humanos , Rim/fisiopatologia , Masculino , Mutação , Fenótipo , Anormalidades Urogenitais/fisiopatologia , Refluxo Vesicoureteral/fisiopatologia , Sequenciamento do Exoma
12.
Eur J Nutr ; 57(5): 1957-1967, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28573457

RESUMO

PURPOSE: Mitochondrial dysfunction plays an important role in the development of obesity and obesity-associated metabolic diseases. METHODS: In this study, we dynamically observed the characteristics of mitochondrial damage in a rat model of diet-induced obesity (DIO). From the 2nd to the 10th week, animals were killed every 2 weeks and the heart, liver, kidney, and testicular tissues were harvested. Mitochondria were isolated and the activities of respiratory chain complexes I, II, III, and IV as well as the 8-Hydroxy-2-deoxy Guanosine content were determined. Reactive oxygen species and malondialdehyde were measured. RESULTS: Mitochondrial damages were observed in the heart and liver of DIO and DR rats, and the damages occurred later in DR group than that in DIO group. The mitochondrial membrane potential of heart and liver decreased in DIO and DR groups. The activity of the heart mitochondria complexes I, III, and IV (composing NADH oxidative respiratory) was higher in the early stage of DIO and lower in the end of week 10. The higher activity of the liver complexes I, III, and IV was found until the end of week 10 in DIO and DR groups, accompanied with enhanced oxidative stress. Besides, mitochondrial DNA damages were observed in all tissues. CONCLUSION: In DIO rats, the heart mitochondrial dysfunction occurred first and the liver presented the strongest compensatory ability against oxidative stress.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Transporte de Elétrons/fisiologia , Obesidade/complicações , Estresse Oxidativo/fisiologia , Animais , Masculino , Malondialdeído/metabolismo , Mitocôndrias/metabolismo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio
13.
Angew Chem Int Ed Engl ; 55(18): 5477-82, 2016 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-27010667

RESUMO

Photodynamic therapy (PDT) has been applied in cancer treatment by utilizing reactive oxygen species to kill cancer cells. However, a high concentration of glutathione (GSH) is present in cancer cells and can consume reactive oxygen species. To address this problem, we report the development of a photosensitizer-MnO2 nanosystem for highly efficient PDT. In our design, MnO2 nanosheets adsorb photosensitizer chlorin e6 (Ce6), protect it from self-destruction upon light irradiation, and efficiently deliver it into cells. The nanosystem also inhibits extracellular singlet oxygen generation by Ce6, leading to fewer side effects. Once endocytosed, the MnO2 nanosheets are reduced by intracellular GSH. As a result, the nanosystem is disintegrated, simultaneously releasing Ce6 and decreasing the level of GSH for highly efficient PDT. Moreover, fluorescence recovery, accompanied by the dissolution of MnO2 nanosheets, can provide a fluorescence signal for monitoring the efficacy of delivery.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Preparações de Ação Retardada/metabolismo , Glutationa/metabolismo , Compostos de Manganês/metabolismo , Óxidos/metabolismo , Fármacos Fotossensibilizantes/administração & dosagem , Porfirinas/administração & dosagem , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Clorofilídeos , Preparações de Ação Retardada/química , Feminino , Humanos , Células MCF-7 , Compostos de Manganês/química , Camundongos Nus , Nanoestruturas/química , Oxirredução , Óxidos/química , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo
14.
Theor Appl Genet ; 128(10): 2077-84, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26133735

RESUMO

KEY MESSAGE: A new broad-spectrum powdery mildew resistance allele Pm2c was identified and mapped in Chinese wheat landrace Niaomai. Chinese wheat landrace Niaomai showed resistance to 27 of 28 Chinese Blumeria graminis f. sp tritici (Bgt) races. Genetic analysis of an F2 population and its derived F2:3 families from the cross Niaomai × Mingxian 169 and backcross population, Niaomai/2*Mingxian 169, indicated that the resistance of Niaomai to Bgt races was conferred by a single dominant resistance gene, temporarily designated PmNM. Molecular tagging showed that PmNM was located on chromosome 5DS and flanked by SSR markers Xcfd81 and Xcfd78 with the genetic distances of 0.1/0.4 cM and 4.9/7.5 cM, respectively. Niaomai showed a different array of responses compared to lines with Pm2a, Pm2b, PmD57-5D, PmLX66, PmX3986-2 and Pm48 genes, sharing the same Xcfd81 allele but differing from Xcfd78 allele for Pm2a and Pm2b lines. Allelism tests based on crosses of Niaomai with Ulka/8*Cc and KM2939 showed that PmNM is allelic to Pm2a and Pm2b. We concluded that PmNM is a new allele of Pm2, re-designated Pm2c. Pm2c could be transferred into wheat cultivars by marker-assisted selection to improve the powdery mildew resistance of breeding cultivars/lines.


Assuntos
Ascomicetos , Resistência à Doença/genética , Doenças das Plantas/genética , Triticum/genética , Alelos , Mapeamento Cromossômico , Cruzamentos Genéticos , Genes Dominantes , Genes de Plantas , Marcadores Genéticos , Repetições de Microssatélites , Fenótipo , Melhoramento Vegetal , Doenças das Plantas/microbiologia , Triticum/microbiologia
15.
PLoS One ; 19(2): e0298312, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38359065

RESUMO

The development of digital economy is a strategic choice to grasp the revolution of new science and technology and the new opportunities of industrial reform. The development of digital economy depends on the good support of policy and theoretical system. Therefore, the quantitative evaluation of policy texts provides the basis of decision-making and the suggestions of path optimization for the formulation and improvement of digital economy policy of China. By selecting the text of digital economy policy issued by China government, the paper constructs a quantitative evaluation model of digital economy policy using the methods of content analysis and text mining. The empirical research results show that the overall design evaluation of the selected policy is relatively reasonable. Six policies were evaluated as excellent and two as acceptable. In view of the problems such as lack of predictive policy in the policy type, lack of specific policy in the policy timeliness, imbalance in the use of policy guarantee, and lack of comprehensive coverage in the policy objectives, the paper puts forward corresponding countermeasures and suggestions.


Assuntos
Mineração de Dados , Governo , China , Indústrias , Políticas , Desenvolvimento Econômico
16.
Biosens Bioelectron ; 246: 115839, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38042054

RESUMO

Rapid, sensitive and selective biosensing is highly important for analyzing biological targets and dynamic physiological processes in cells and living organisms. As an emerging tool, clustered regularly interspaced short palindromic repeats (CRISPR) system is featured with excellent complementary-dependent cleavage and efficient trans-cleavage ability. These merits enable CRISPR system to improve the specificity, sensitivity, and speed for molecular detection. Herein, the structures and functions of several CRISPR proteins for biosensing are summarized in depth. Moreover, the strategies of target recognition, signal conversion, and signal amplification for CRISPR-based biosensing were highlighted from the perspective of biosensor design principles. The state-of-art applications and recent advances of CRISPR system are then outlined, with emphasis on their fluorescent, electrochemical, colorimetric, and applications in POCT technology. Finally, the current challenges and future prospects of this frontier research area are discussed.


Assuntos
Técnicas Biossensoriais , Colorimetria , Corantes , Sistemas CRISPR-Cas/genética
17.
Forensic Sci Int Genet ; 70: 103031, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38493735

RESUMO

Blood-containing mixtures are frequently encountered at crime scenes involving violence and murder. However, the presence of blood, and the association of blood with a specific donor within these mixtures present significant challenges in forensic analysis. In light of these challenges, this study sought to address these issues by leveraging blood-specific methylation sites and closely linked microhaplotype sites, proposing a novel composite genetic marker known as "blood-specific methylation-microhaplotype". This marker was designed to the detection of blood and the determination of blood donor within blood-containing mixtures. According to the selection criteria mentioned in the Materials and Methods section, we selected 10 blood-specific methylation-microhaplotype loci for inclusion in this study. Among these loci, eight exhibited blood-specific hypomethylation, while the remaining two displayed blood-specific hypermethylation. Based on data obtained from 124 individual samples in our study, the combined discrimination power (CPD) of these 10 successfully sequenced loci was 0.999999298. The sample allele methylation rate (Ram) was obtained from massive parallel sequencing (MPS), which was defined as the proportion of methylated reads to the total clustered reads that were genotyped to a specific allele. To develop an allele type classification model capable of identifying the presence of blood and the blood donor, we used the Random Forest algorithm. This model was trained and evaluated using the Ram distribution of individual samples and the Ram distribution of simulated shared alleles. Subsequently, we applied the developed allele type classification model to predict alleles within actual mixtures, trying to exclude non-blood-specific alleles, ultimately allowing us to identify the presence of blood and the blood donor in the blood-containing mixtures. Our findings demonstrate that these blood-specific methylation-microhaplotype loci have the capability to not only detect the presence of blood but also accurately associate blood with the true donor in blood-containing mixtures with the mixing ratios of 1:29, 1:19, 1:9, 1:4, 1:2, 2:1, 7:1, 8:1, 31:1 and 36:1 (blood:non-blood) by DNA mixture interpretation methods. In addition, the presence of blood and the true blood donor could be identified in a mixture containing four body fluids (blood:vaginal fluid:semen:saliva = 1:1:1:1). It is important to note that while these loci exhibit great potential, the impact of allele dropouts and alleles misidentification must be considered when interpreting the results. This is a preliminary study utilising blood-specific methylation-microhaplotype as a complementary tool to other well-established genetic markers (STR, SNP, microhaplotype, etc.) for the analysis in blood-containing mixtures.


Assuntos
Doadores de Sangue , Líquidos Corporais , Feminino , Humanos , Marcadores Genéticos , Genótipo , Metilação de DNA , Impressões Digitais de DNA/métodos , Polimorfismo de Nucleotídeo Único , Genética Forense
18.
Clin Nutr ; 42(12): 2457-2467, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37925778

RESUMO

BACKGROUND: Osteoporosis and obesity are closely related, and the relationships between different types of obesity and osteoporosis are inconsistent. OBJECTIVE: Our objective was to summarize earlier data concerning the association between osteoporosis and obesity (general and central), and to compare the impacts of these two obesity indicators on osteoporosis. METHODS: From inception to May 2021, a comprehensive search in electronic bibliographic databases was conducted, and the search was updated in December 2021, July 2022 and June 2023. The data were independently extracted and evaluated by two investigators from epidemiological studies that reported the impact of obesity on the odds of incident osteoporosis. RESULTS: There were 24 studies included in the final analysis when it came to general obesity measured by body mass index (BMI). Individuals with overweight and obesity had decreased odds of osteoporosis (odds ratio (OR), 0.451, 95% confidence intervals (CIs): 0.366-0.557). Sensitivity analyses showed that both overweight and obesity were decreased odds of osteoporosis, with reductions of 48.6% and 70.1%, respectively (OR, 0.514, 95% CI: 0.407-0.649; OR, 0.299, 95% CI: 0.207-0.433). Conversely, individuals classified as underweight were found to have higher odds of osteoporosis (OR, 2.540, 95% CI: 1.483-4.350). In term of central obesity, the final analysis consisted of 7 studies. No significant association was observed between central obesity and osteoporosis (OR, 0.913, 95% CI: 0.761-1.096). CONCLUSIONS: General overweight and obesity were associated with lower odds of developing osteoporosis, whereas underweight was associated with higher odds. However, central obesity did not show a significant association with osteoporosis. These findings underscore the importance of considering the impact of obesity on osteoporosis. Further research is necessary to reinforce the evidence and validate our findings.


Assuntos
Sobrepeso , Magreza , Humanos , Sobrepeso/complicações , Sobrepeso/epidemiologia , Obesidade Abdominal , Obesidade/complicações , Obesidade/epidemiologia , Índice de Massa Corporal
19.
Am J Clin Nutr ; 118(3): 614-626, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37661106

RESUMO

BACKGROUND: Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are new drugs for the treatment of obesity. OBJECTIVE: To assess the weight-loss effects of GLP-1RAs in the treatment of patients with overweight or obesity without diabetes. METHODS: This is a systematic review with meta-analysis and trial sequential analysis. PubMed, Embase, and Cochrane Central Register of Controlled Trials were searched from their inception to January 1, 2022. Eligible trials report on outcomes including body weight (BW), body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), or total body fat (TBF). Mean differences (MDs) and standardized mean differences (SMDs) were summarized using random-effects models. RESULTS: Forty-one trials involving 15,135 participants were included. Compared with controls, GLP-1RAs significantly reduced BW (MD -5.319 kg, 95% CI: -6.465, -4.174), BMI (MD -2.373 kg/m2, 95% CI: -2.821, -1.924), WC (MD -4.302 cm, CI:-5.185 to -3.419), WHR (MD -0.011, CI -0.015 to -0.007), but not TBF (MD -0.320%, CI -1.420 to -0.780). Trial sequential analysis (TSA) supported conclusive evidence of the effects of GLP-1RAs on BW, BMI, and WC for weight loss. GLP-1RAs had nonlinear dose-response relationships with weight loss. Extensive sensitivity analyses demonstrated the robustness of the results, though the GRADE certainty of the evidence ranged from high to very low. High to moderate GRADE certainty of evidence suggested semaglutide as the most effective GLP-1RA agent, with the best efficacy and low to moderate risk of adverse effects. CONCLUSIONS: The present study provides conclusive evidence for the effect of GLP-1RAs on weight loss in a nonlinear dose-response manner in patients with obesity or overweight without diabetes. In terms of changes in BW, BMI, and WC, there is firm evidence for the overall weight-loss effects of GLP-1RAs. Of the GLP-1RAs, semaglutide might be the most effective agent.


Assuntos
Receptor do Peptídeo Semelhante ao Glucagon 1 , Sobrepeso , Humanos , Sobrepeso/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Obesidade/tratamento farmacológico , Peso Corporal , Redução de Peso
20.
Front Nutr ; 9: 925870, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35928840

RESUMO

Background: China has the largest number of patients with Type 2 Diabetes Mellitus (T2DM), and it tends to increasingly grow in the future, putting an enormous burden on disease control and prevention in China. While glycemic variability (GV) came to be an important indicator of blood glucose control in diabetic patients, studies suggested that premeal snacks may help blood glucose control, but there are still some problems to be researched. Therefore, we designed this trial to evaluate which kind of premeal snacks would lead to better effects on GV under two diet patterns in pre-diabetes subjects and to evaluate assessments of acceptability and compliance, behavior, and metabolism changes in individuals will be described. Methods and analysis: The study is a single-center, open-label, multiparallel group, randomized controlled trial. A total of 32 male and female volunteers will be randomized into 4 groups in a single allocated ratio of soy milk (powder) snack, milk (powder) snack, almonds snack, and placebo control with 250 ml of water taken 30 min before lunch, respectively. The study consists of two intervention periods over 11 days. The first intervention period under habitual diet conditions from D3 to D6 (4 days), during which all subjects are asked to maintain their habitual eating and daily activities similar to the run-in period. The second intervention consists of prelunch snacks with standard meals. We will examine both the effect of GV and various metabolic and behavioral outcomes potentially associated with the interventions. At the end of this study, we will assess the acceptability and maintainability of the intervention through interviews. Clinical trial registration: Chinese Clinical Trial Registry, identifier ChiCTR2200058935.

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