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1.
BMC Plant Biol ; 24(1): 829, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39232709

RESUMO

BACKGROUND: In research to improve the quality of transgenic crops, it is often necessary to introduce multiple functionally related genes into recipient plants simultaneously to improve crop genetic traits effectively. Compared with unidirectional promoters, bidirectional promoters simultaneously regulate the expression of multiple genes and improve the efficiency of biotechnology. Therefore, in this study, bidirectional gene pairs were systematically analyzed in Gossypium hirsutum TM-1, and the structure, function and evolutionary relationships of the bidirectional genes were analyzed. The endogenous bidirectional promoters of cotton were mined, and their specific regulatory elements and biological functions were explored to provide useful promoter resources and a theoretical basis for cultivating new cotton germplasms with excellent fiber quality. RESULTS: Using an improved search model, a total of 1,383 bidirectional transcript pairs were identified in the Gossypium hirsutum TM-1 genome, and their gene structure and functional annotations were systematically analyzed. Thirty bidirectional intergenic sequences were randomly screened for promoter activity analysis via a transient expression system, and 25 intergenic sequences were found to have bidirectional promoter activity. Comparative analysis of the bidirectional gene profiles of the four cotton subspecies revealed that these subspecies presented abundant bidirectional gene pairs with high homology and that the bidirectional genes in the cotton subspecies were more similar in terms of their molecular functions, cellular components and biological processes. In addition, parallel analysis of bidirectional genes in dicotyledons and monocotyledons revealed that abundant bidirectional gene pairs exist in different species. Although the total number of orthologous bidirectional genes was similar, there was a significant difference in the number of orthologous bidirectional gene pairs between dicotyledons and monocotyledons. This evolutionary analysis of the function and structure of homologous bidirectional gene pairs in different varieties and different subspecies of the same species revealed potential pathways by which these gene pairs originated, which may be necessary for the evolution of a new species. CONCLUSION: In this study, many bidirectional gene pairs in Gossypium hirsutum TM-1 were identified using computer programming, and systematic analysis was conducted to explore their functions and evolutionary relationships. In addition, the promoter activity of the bidirectional intergenic sequences was verified. The combination of computer programming screening, experimental validation and other methods is expected to provide preferred bidirectional promoters for transgenic breeding work via multigene cotransformation methods, and this information is valuable for genetic engineering research and applications.


Assuntos
DNA Intergênico , Gossypium , Regiões Promotoras Genéticas , Gossypium/genética , Regiões Promotoras Genéticas/genética , DNA Intergênico/genética , Genes de Plantas , Regulação da Expressão Gênica de Plantas , Genoma de Planta
2.
Opt Express ; 32(3): 3751-3763, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297589

RESUMO

To address the needs of polarized light navigation for accurate position information of feature points in the sky, an accurate solar position detection method based on an all-sky polarization pattern imaging system is proposed. Unlike the traditional spot-based solar position detection method, this method uses the polarization information inherent in the atmosphere to accurately measure solar position. This approach is characterized by simple detection, high accuracy, and wide application range. The optical acquisition system is composed of three miniature large-field camera modules and polarizers, which enables a more compact structure, smaller size, and lesser height. Based on this principle, the solar position solution algorithm was simulated and then verified in various weather environments using the optical acquisition system built as part of this study. Solar position was detected at different moments on the same day in clear weather, and the accuracy of the measured solar altitude and azimuth angles was 0.024° and 0.03°, respectively. The accuracy of the measured solar altitude and azimuth angles was 0.08° and 0.05°, respectively, when the sun was shielded by high-rise buildings and 0.3° and 0.1° when the sun was shielded by branches and tree leaves. Aerosol concentrations exceeding a certain amount destroyed the Rayleigh distribution pattern of polarized light, thus affecting solar position detection accuracy. It is concluded that this novel detection method can not only meet the needs of polarized light navigation for solar position, but also provide a new exploration idea for enthusiasts who are eager to explore the mysteries of the universe.

3.
Clin Lab ; 70(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38623669

RESUMO

BACKGROUND: We aimed to evaluate the diagnostic capabilities of Chinese laboratories for inherited metabolic disorders (IMDs) using gas chromatography-mass spectrometry (GC-MS) on urine samples. Meanwhile, based on the result of the pilot external quality assessment (EQA) scheme, we hope to establish a standardized and reliable procedure for future EQA practice. METHODS: We recruited laboratories that participated in the EQA of quantitative analysis of urinary organic acids with GC-MS before joining the surveys. In each survey, a set of five real urine samples was distributed to each participant. The participants should analyze the sample by GC-MS and report the "analytical result", "the most likely diagnosis", and "recommendation for further tests" to the NCCL before the deadline. RESULTS: A total of 21 laboratories participated in the scheme. The pass rates were 94.4% in 2020 and 89.5% in 2021. For all eight IMDs tested, the analytical proficiency rates ranged from 84.7% - 100%, and the interpretational performance rate ranged from 88.2% - 97.0%. The performance on hyperphenylalaninemia (HPA), 3-methylcrotonyl-CoA carboxylase deficiency (MCCD), and ethylmalonic encephalopathy (EE) samples were not satisfactory. CONCLUSIONS: In general, the participants of this pilot EQA scheme are equipped with the basic capability for qualitative organic acid analysis and interpretation of the results. Limited by the small size of laboratories and samples involved, this activity could not fully reflect the state of clinical practice of Chinese laboratories. NCCL will improve the EQA scheme and implement more EQA activities in the future.


Assuntos
Doenças Metabólicas , Fenilcetonúrias , Humanos , Controle de Qualidade , Laboratórios , Doenças Metabólicas/diagnóstico , China , Garantia da Qualidade dos Cuidados de Saúde
4.
Clin Lab ; 70(5)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38747911

RESUMO

BACKGROUND: This study aims to evaluate the ability of laboratories to perform spinal muscular atrophy (SMA) genetic testing in newborns based on dried blood spot (DBS) samples, and to provide reference data and advance preparation for establishing the pilot external quality assessment (EQA) scheme for SMA genetic testing of newborns in China. METHODS: The pilot EQA scheme contents and evaluation principles of this project were designed by National Center for Clinical Laboratories (NCCL), National Health Commission. Two surveys were carried out in 2022, and 5 batches of blood spots were submitted to the participating laboratory each time. All participating laboratories conducted testing upon receiving samples, and test results were submitted to NCCL within the specified date. RESULTS: The return rates were 75.0% (21/28) and 95.2% (20/21) in the first and second surveys, respectively. The total return rate of the two examinations was 83.7% (41/49). Nineteen laboratories (19/21, 90.5%) had a full score passing on the first survey, while in the second survey twenty laboratories (20/20, 100%) scored full. CONCLUSIONS: This pilot EQA survey provides a preliminary understanding of the capability of SMA genetic testing for newborns across laboratories in China. A few laboratories had technical or operational problems in testing. It is, therefore, of importance to strengthen laboratory management and to improve testing capacity for the establishment of a national EQA scheme for newborn SMA genetic testing.


Assuntos
Testes Genéticos , Atrofia Muscular Espinal , Triagem Neonatal , Humanos , Recém-Nascido , Atrofia Muscular Espinal/diagnóstico , Atrofia Muscular Espinal/genética , Projetos Piloto , Testes Genéticos/normas , Testes Genéticos/métodos , Triagem Neonatal/normas , Triagem Neonatal/métodos , China , Teste em Amostras de Sangue Seco/normas , Teste em Amostras de Sangue Seco/métodos , Garantia da Qualidade dos Cuidados de Saúde , Laboratórios Clínicos/normas , Proteína 1 de Sobrevivência do Neurônio Motor/genética
5.
Planta ; 258(2): 34, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37378818

RESUMO

MAIN CONCLUSION: Transcriptomics and methylomics were used to identify the potential effects resulting from GM rice breeding stacks, which provided scientific data for the safety assessment strategy of stacked GM crops in China. Gene interaction is one of the main concerns for stacked genetically modified crop safety. With the development of technology, the combination of omics and bioinformatics has become a useful tool to evaluate the unintended effects of genetically modified crops. In this study, transcriptomics and methylomics were used as molecular profiling techniques to identify the potential effects of stack through breeding. Stacked transgenic rice En-12 × Ec-26 was used as material, which was obtained through hybridization using parents En-12 and Ec-26, in which the foreign protein can form functional EPSPS protein by intein-mediated trans-splitting. Differentially methylated region (DMR) analysis showed that the effect of stacking breeding on methylation was less than that of genetic transformation at the methylome level. Differentially expressed gene (DEG) analysis showed that the DEGs between En-12 × Ec-26 and its parents were far fewer than those between transgenic rice and Zhonghua 11 (ZH11), and no unintended new genes were found in En-12 × Ec-26. Statistical analysis of gene expression and methylation involved in shikimic acid metabolism showed that there was no difference in gene expression, although there were 16 and 10 DMR genes between En-12 × Ec-26 and its parents (En and Ec) in methylation, respectively. The results indicated that the effect of stacking breeding on gene expression and DNA methylation was less than the effect of genetic transformation. This study provides scientific data supporting safety assessments of stacked GM crops in China.


Assuntos
Oryza , Transcriptoma , Animais , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Oryza/genética , Oryza/metabolismo , Produtos Agrícolas/genética , Epigenoma , Melhoramento Vegetal , Animais Geneticamente Modificados , Glifosato
6.
Phys Chem Chem Phys ; 25(6): 5029-5036, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36722879

RESUMO

Recently, layered BeN4 as a novel Dirac semimetal has been fabricated (M. Bykov, T. Fedotenko, S. Chariton et al. Phys. Rev. Lett., 2021, 126, 175501). Motivated by the experiment, we perform first-principles calculations to predict the stability, magnetic configurations, and electronic structures of unsaturated BeN4 nanoribbons with an armchair-terminated edge. The magnetic interactions and electronic properties of BeN4 nanoribbons are sensitively influenced by the edge morphology. The BeN4 nanoribbons with both edges occupied by Be atoms undergo a transition from a ferromagnetic (FM) metal to an antiferromagnetic (AFM) semiconductor with the increase of ribbon width. The configurations with edges situated by Be and N atoms are FM/ferrimagnetic (FIM) metals or nearly half-metals, and the spin polarizability is as high as 85% when the ribbon width is N = 5. The nanoribbons with both edge sites occupied by pentagonal N atoms are nonmagnetic (NM), while the nanoribbons terminated by N atoms in a hexagonal ring are FM metals. We also explore the magnetic properties and band structures of BeN4 nanoribbons with hydrogen passivation. Our results open up a versatile edge engineering avenue to design BeN4-based spintronic and nanoelectronic devices.

7.
Postgrad Med J ; 99(1175): 1000-1007, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36917816

RESUMO

PURPOSE: Previous studies evaluating the impact of antibiotic timing on mortality in sepsis have shown conflicting results. We performed a meta-analysis to evaluate the association between door-to-antibiotic time (each hour of delay) and mortality in sepsis. METHODS: We searched PubMed and Embase through 10 November 2022 to identity cohort studies that evaluated the adjusted association between door-to-antibiotic time (each hour of delay) and mortality in adult patients with sepsis. The primary outcome was mortality. Analysis was based on inverse-variance weighting using a fixed-effects model. The variances were derived from the logarithms of the reported confidence intervals (CIs) for associations. We estimated the odds ratio, 95% CI, and number needed to treat for the pooled data. RESULTS: Fifteen cohort studies involving 106 845 patients were included in the meta-analysis. Door-to-antibiotic time (each hour of delay) was associated with increased risk of mortality (odds ratio: 1.07; 95% CI: 1.06-1.08; P < 0.0001; number needed to treat = 91), with high heterogeneity (I2 = 82.2%). The association was robust in sensitivity analyses and consistent in subgroup analyses. No publication bias was found. CONCLUSION: In adult patients with sepsis, each hour of delay in antibiotic administration is associated with increased odds of mortality. Key messages What is already known on this topic Sepsis is a common and lethal syndrome that affects millions of people worldwide. The updated 2018 Surviving Sepsis Campaign guidelines recommended initiating empirical broad-spectrum antibiotic coverage within 1 hour of identification of sepsis and septic shock. Delay in antibiotic administration may increase the risk of mortality in patients with sepsis. What this study adds This meta-analysis evaluates and quantifies the association between door-to-antibiotic time (each hour of delay) and mortality in patients with sepsis. Each hour of delay in antibiotic administration is associated with increased odds of mortality in sepsis. The number needed to treat (NNT) with delayed antibiotic administration for one additional death was 91. How this study might affect research, practice, or policy: More efforts should be made to speed up the diagnosis of sepsis or sepsis shock.


Assuntos
Sepse , Choque Séptico , Humanos , Antibacterianos/uso terapêutico , Sepse/diagnóstico
8.
Opt Express ; 30(11): 19665-19683, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-36221737

RESUMO

In recent years, integrated polarized light/inertial heading measurement systems have been widely used to obtain autonomous heading measurements of small unmanned combat platforms in the case of satellite navigation rejection. However, existing polarized light/inertial heading measurement systems have certain limitations. For example, they can only measure the heading angle in environments where continuous observations can be obtained. When encountering a complex environment with trees and/or tall buildings, the measured heading angle will contain sharp noise which greatly affects its accuracy. In particular, when encountering an underpass, it will lead to the complete loss of lock of the polarized light compass signal. Therefore, for the problem of sharp noise arising from a complex environment, a robust Cubature Kalman filter (CKF) data-fusion algorithm is proposed and verified by experiments. It is proved that the robust CKF algorithm has a certain ability to filter out the effects of poor measurements. After application of the robust CKF algorithm, the Root Mean Square Error (RMSE) of the heading angle reaches 0.3612°. This method solves the problem of low precision and poor stability of the polarized light/inertial system when high buildings and/or trees are contained in a complex environment. Next, in view of the problem that the polarized light compass signal is completely lost due to passing through an underground passage, a random forest regression (RFR) neural network model is established and introduced into the combined system. Simulated and outdoor experiments are carried out to verify the designed model using data obtained with a vehicle. The RMSE of the heading angle obtained in the experiment is 1.1894°, which solves the problem that the polarized light/inertial system cannot utilize discontinuous observations when attempting to detect the carrier heading angle.

9.
Transgenic Res ; 29(1): 69-80, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31654191

RESUMO

Controlling transgene flow in China is important, as this country is part of the center of origin of rice. A gene-splitting technique based on intein-mediated trans-splicing represents a new strategy for controlling transgene flow via biological measures. In this study, the G2-aroA gene which provides glyphosate tolerance was split into an N-terminal and a C-terminal region, which were then fused to intein N and intein C of the Ssp DnaE intein, ultimately forming EPSPSn:In and Ic:EPSPSc fusion genes, respectively. These fusion genes were subsequently transformed into the rice cultivar Zhonghua 11 via the Agrobacterium-mediated method. The two split gene fragments were then introduced into the same rice genome by genetic crossings. Glyphosate tolerance analysis revealed that the functional target protein was reconstituted by Ssp DnaE intein-mediated trans-splicing and that the resultant hybrid rice was glyphosate tolerant. The reassembly efficiency of the split gene fragments ranged from 67 to 91% at the molecular level, and 100% of the hybrid F1 progeny were glyphosate tolerant. Transgene flow experiments showed that when the split gene fragments are inserted into homologous chromosomes, the gene-splitting technique can completely avoid the escape of the target trait to the environment. This report is the first on the reassembly efficiency and effectiveness of transgene flow containment via gene splitting in rice. This study provides not only a new biological strategy for controlling rice transgene flow but also a new method for cultivating hybrid transgenic rice.


Assuntos
Cromossomos de Plantas/genética , Recombinação Homóloga , Oryza/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Processamento de Proteína , Transgenes
10.
Plant J ; 93(6): 1007-1016, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29356248

RESUMO

Gene stacking is a developing trend in agricultural biotechnology. Unintended effects in stacked transgenic plants are safety issues considered by the public and researchers. Omics techniques provide useful tools to assess unintended effects. In this paper, stacked transgenic maize 12-5×IE034 that contained insecticidal cry and glyphosate tolerance G10-epsps genes was obtained by crossing of transgenic maize varieties 12-5 and IE034. Transcriptome and metabolome analyses were performed for different maize varieties, including 12-5×IE034, 12-5, IE034, and conventional varieties collected from different provinces in China. The transcriptome results were as follows. The nine maize varieties had obvious differences in gene expression. There were 3561-5538 differentially expressed genes between 12-5×IE034 and its parents and transgenic receptor, which were far fewer than the number of differentially expressed genes in different traditional maize varieties. Cluster analysis indicated that there were close relationships between 12-5×IE034 and its parents. The metabolome results were as follows. For the nine detected maize varieties, the number of different metabolites ranged from 0 to 240. Compared with its parents, 12-5 and IE034, the hybrid variety 12-5×IE034 had 15 and 112 different metabolites, respectively. Hierarchical cluster analysis with Pearson's correlation analysis showed that the differences between 12-5×IE034 and its parents were fewer than those between other maize varieties. Shikimate pathway-related genes and metabolites analysis results showed that the effects of hybrid stacking are less than those from transformation and differing genotypes. Thus, the differences due to breeding stack were fewer than those due to natural variation among maize varieties. This paper provides scientific data for assessing unintended effects in stacked transgenic plants.


Assuntos
3-Fosfoshikimato 1-Carboxiviniltransferase/genética , Proteínas de Bactérias/genética , Endotoxinas/genética , Proteínas Hemolisinas/genética , Metaboloma , Transcriptoma , Zea mays/genética , Zea mays/metabolismo , 3-Fosfoshikimato 1-Carboxiviniltransferase/metabolismo , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/metabolismo , Endotoxinas/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genótipo , Glicina/análogos & derivados , Glicina/farmacologia , Proteínas Hemolisinas/metabolismo , Resistência a Herbicidas/genética , Metabolômica , Plantas Geneticamente Modificadas , Especificidade da Espécie , Transgenes/genética , Zea mays/classificação , Glifosato
11.
BMC Plant Biol ; 19(1): 346, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31391002

RESUMO

BACKGROUND: The safety assessment and control of stacked transgenic crops is increasingly important due to continuous crop development and is urgently needed in China. The genetic stability of foreign genes and unintended effects are the primary problems encountered in safety assessment. Omics techniques are useful for addressing these problems. The stacked transgenic maize variety 12-5 × IE034, which has insect-resistant and glyphosate-tolerant traits, was developed via a breeding stack using 12-5 and IE034 as parents. Using 12-5 × IE034, its parents (12-5 and IE034), and different maize varieties as materials, we performed proteomic profiling, molecular characterization and a genetic stability analysis. RESULTS: Our results showed that the copy number of foreign genes in 12-5 × IE034 is identical to that of its parents 12-5 and IE034. Foreign genes can be stably inherited over different generations. Proteomic profiling analysis found no newly expressed proteins in 12-5 × IE034, and the differences in protein expression between 12 and 5 × IE034 and its parents were within the range of variation of conventional maize varieties. The expression levels of key enzymes participating in the shikimic acid pathway which is related to glyphosate tolerance of 12-5 × IE034 were not significantly different from those of its parents or five conventional maize varieties, which indicated that without selective pressure by glyphosate, the introduced EPSPS synthase is not has a pronounced impact on the synthesis of aromatic amino acids in maize. CONCLUSIONS: Stacked-trait development via conventional breeding did not have an impact on the genetic stability of T-DNA, and the impact of stacked breeding on the maize proteome was less significant than that of genotypic differences. The results of this study provide a theoretical basis for the development of a safety assessment approach for stacked-trait transgenic crops in China.


Assuntos
Variação Genética , Melhoramento Vegetal , Plantas Geneticamente Modificadas , Zea mays/genética , China , Inocuidade dos Alimentos , Dosagem de Genes , Instabilidade Genômica , Análise de Perigos e Pontos Críticos de Controle , Proteômica
12.
Int J Mol Sci ; 19(11)2018 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-30360512

RESUMO

Stacked traits have become an important trend in the current development of genomically modified crops. The bidirectional promoter can not only prevent the co-suppression of multigene expression, but also increase the efficiency of the cultivation of transgenic plants with multigenes. In Gossypium hirsutum, Ghrack1 and Ghuhrf1 are head-to-head gene pairs located on chromosome D09. We cloned the 1429-bp intergenic region between the Ghrack1 and Ghuhrf1 genes from Gossypium hirsutum. The cloned DNA fragment GhZU had the characteristics of a bidirectional promoter, with 38.7% G+C content, three CpG islands and no TATA-box. Using gfp and gus as reporter genes, a series of expression vectors were constructed into young leaves of tobacco. The histochemical GUS (Beta-glucuronidase) assay and GFP (green fluorescence protein) detection results indicated that GhZU could drive the expression of the reporter genes gus and gfp simultaneously in both orientations. Furthermore, we transformed the expression vectors into Arabidopsis and found that GUS was concentrated at vigorous growth sites, such as the leaf tip, the base of the leaves and pod, and the stigma. GFP was also mainly expressed in the epidermis of young leaves. In summary, we determined that the intergenic region GhZU was an orientation-dependent bidirectional promoter, and this is the first report on the bidirectional promoter from Gossypium hirsutum. Our findings in this study are likely to enhance understanding on the regulatory mechanisms of plant bidirectional promoters.


Assuntos
Arabidopsis/metabolismo , Gossypium/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Regiões Promotoras Genéticas/genética , Arabidopsis/genética , Clonagem Molecular , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Gossypium/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética
13.
Inorg Chem ; 54(22): 10593-603, 2015 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-26505902

RESUMO

With mixed transition-metal-complex, alkali-metal, or organic cations as structure-directing agents, a series of novel two-dimensional (2D) layered inorganic-organic hybrid iodoargentates, namely, Kx[TM(2,2-bipy)3]2Ag6I11 (TM = Mn (1), Fe (2), Co (3), Ni (4), Zn (5); x = 0.89-1) and [(Ni(2,2-bipy)3][H-2,2-bipy]Ag3I6 (6), have been solvothermally synthesized and structurally characterized. All the title compounds feature 2D microporous layers composed by [Ag3I7] secondary building units based on AgI4 tetrahedra. Differently, the [Ag3I7] trimers are directly interconnected via corner-sharing to form the 2D [Ag6I11](5-) layer in compounds 1-5, whereas two neighboring [Ag3I7] trimers are initially condensed into a hexameric [Ag6I12] ternary building unit as a new node, which further self-assembles, leading to the 2D [Ag6I10](4-) layer in compound 6. The UV-vis diffuse-reflectance measurements reveal that all the compounds possess proper semiconductor behaviors with tunable band gaps of 1.66-2.75 eV, which lead to highly efficient photocatalytic degradation activities over organic pollutants under visible light irradiation compared to that of N-dotted P25. Interestingly, all the samples feature distinct photodegradative speeds at the same reaction conditions, and compound 1 features the highest photocatalytic activity among the title phases. The luminescence properties, band structures, and thermal stabilities were also studied.

14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(12): 3529-33, 2015 Dec.
Artigo em Zh | MEDLINE | ID: mdl-26964244

RESUMO

Because traditional method for tunable grating fabrication has harsh process condition, complex fabrication process, high costs and long cycle. Proposed a low-cost, simple process, can be prepared in large quantities gradient grating process method, based on self-assembly process using the rigid film/flexible substrate and oxygen plasma method prepared a micron scale gradient grating. Use of plasma free time controllability and excellent elastic of PDMS obtained the desired grating. First, polyethylene terephthalate (PET) was spin-coated layer of polydimethylsiloxane (PDMS) film on the thin film, two-layer film to be cured PDMS film after bending and treated with an oxygen plasma (plasma), in generating a rigid surface oxide layer, With flexible PET rigid layer applied uniform stress, when the stress exceeds the critical value, the PDMS substrate to form a self-assembled structure grating fold. Due to changes in prestressed bending, so the PDMS film formation period and height of the grating stepped fold, which is graded grating. Using visible light as the performance test light source for graded grating and selecting first-order diffracted as the detection target. The authors can see the grating has a good diffraction effects and achieves good spectral effect. Experiments show that graded grating has obvious diffraction grating, and the diffraction angle varies significantly, and can be widely used for stress measurement, the flexible gradient grating prepared by this method can also be used to detect changes in the stress strain as a miniature device, the future is expected for miniature spectrometer, scanners, optical communications and other fields.

15.
Cell Biochem Funct ; 32(3): 241-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24114958

RESUMO

Astrocytes, the most common cell type in the brain, play a principal role in the repair of damaged brain tissues during external radiotherapy of brain tumours. As a downstream gene of p53, the effects of Krüppel-like factor 4 (KLF4) in response to X-ray-induced DNA damage in astrocytes are unclear. In the present study, KLF4 expression was upregulated after the exposure of astrocytes isolated from the murine brain. Inhibition of KLF4 expression using lentiviral transduction produced less double-strand DNA breaks (DSB) determined by a neutral comet assay and flow cytometric analysis of phosphorylated histone family 2A variant and more single-strand DNA breaks (SSB) determined by a basic comet assay when the astrocytes were exposed to 4 Gy of X-ray radiation. These data suggest that radiation exposure of the tissues around brain tumour during radiation therapy causes KLF4 overexpression in astrocytes, which induces more DSB and reduces SSB. This causes the adverse effects of radiation therapy in the treatment of brain tumours.


Assuntos
Astrócitos/efeitos da radiação , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Fatores de Transcrição Kruppel-Like/metabolismo , Animais , Astrócitos/metabolismo , Quebras de DNA de Cadeia Simples/efeitos da radiação , Fragmentação do DNA/efeitos da radiação , Histonas/metabolismo , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Camundongos , Camundongos Endogâmicos C57BL
16.
Macromol Biosci ; 24(2): e2300165, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37681479

RESUMO

Full-thickness skin defect has always been a major challenge in clinics due to fibrous hyperplasia in the repair process. Hydrogel composite dressings loaded with anti-fibrotic drugs have been considered as a promising strategy for scarless skin regeneration. In this work, a hydrogel composite (VP-CMCS-OSA) of carboxymethyl chitosan (CMCS) and oxidized sodium alginate (OSA), with loading anti-fibrotic drug verteporfin (VP), is developed based on two-step chemical reactions. Verteporfin is bonded with carboxymethyl chitosan through EDC/NHS treatment to form VP-CMCS, and then VP-CMCS is crosslinked with oxidized sodium alginate by Schiff base reaction to form VP-CMCS-OSA hydrogel. The characterization by SEM, FTIR, and UV-Vis shows the microstructure and chemical bonding of VP-CMCS-OSA. VP-CMCS-OSA hydrogel demonstrates the properties of high tissue adhesion, strong self-healing, and tensile ability. In the full-thickness skin defect model, the VP-CMCS-OSA composite hydrogels hasten wound healing due to the synergistic effects of hydrogels and verteporfin administration. The histological examination reveals the regular collagen arrangement and more skin appendages after VP-CMCS-OSA composite hydrogel treatment, indicating the full-thickness skin regeneration without potential scar formation. The outcomes suggest that the verteporfin-loaded composite hydrogel could be a potential method for scarless skin regeneration.


Assuntos
Quitosana , Hidrogéis , Hidrogéis/farmacologia , Hidrogéis/química , Quitosana/farmacologia , Quitosana/química , Verteporfina/farmacologia , Alginatos/farmacologia , Alginatos/química , Regeneração , Antibacterianos/farmacologia
17.
J Control Release ; 375: 767-775, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39332777

RESUMO

Radionuclide therapy, in particular peptide receptor radionuclide therapy (PRRT), has emerged as a valuable means to combat malignant tumors. The specific affinity of ACUPA peptide toward prostate-specific membrane antigen (PSMA) renders the successful development of PRRT for prostate cancer. The clinical outcome of PRRT is, however, generally challenged by moderate tumor uptake and off-target toxicity. Here, we report on a novel design of Sigma-1 receptor and PSMA dual-receptor targeted peptide (S1R/PSMA-P) for superior radionuclide imaging and therapy of prostate cancer. S1R/PSMA-P was acquired with good purity and could efficiently be labeled with 177Lu to yield 177Lu-S1R/PSMA-P with high specific activity and radiostability. Interestingly, 177Lu-S1R/PSMA-P revealed greatly enhanced affinity to LNCaP cells over single-targeted control 177Lu-PSMA-617. The single photon emission computed tomography (SPECT) imaging demonstrated exceptional uptake and retention of 177Lu-S1R/PSMA-P in LNCaP tumor, affording about 2-fold better tumor accumulation while largely reduced uptake by most normal tissues compared to 177Lu-PSMA-617. The selective uptake in LNCaP tumor was also visualized by positron emission tomography (PET) with 68Ga-S1R/PSMA-P. In accordance, a single and low dosage of 177Lu-S1R/PSMA-P at 11.1 MBq effectively suppressed tumor growth without causing apparent side effects. This dual-targeting strategy presents an appealing radionuclide therapy for malignant tumors.


Assuntos
Antígenos de Superfície , Glutamato Carboxipeptidase II , Lutécio , Camundongos Nus , Neoplasias da Próstata , Radioisótopos , Receptores sigma , Receptor Sigma-1 , Masculino , Receptores sigma/metabolismo , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/metabolismo , Humanos , Animais , Linhagem Celular Tumoral , Antígenos de Superfície/metabolismo , Lutécio/administração & dosagem , Radioisótopos/administração & dosagem , Glutamato Carboxipeptidase II/metabolismo , Compostos Radiofarmacêuticos/farmacocinética , Compostos Radiofarmacêuticos/administração & dosagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Peptídeos/administração & dosagem , Peptídeos/química , Camundongos , Camundongos Endogâmicos BALB C , Distribuição Tecidual , Radioisótopos de Gálio/administração & dosagem
18.
Front Oncol ; 13: 1101582, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37427130

RESUMO

Background: The effectiveness of intravenous lidocaine infusion in managing acute and chronic pain following breast surgery has been a topic of debate. This meta-analysis aims to assess the impact of perioperative intravenous lidocaine on the relief of postoperative pain among patients undergoing breast surgery. Methods: A systematic search of databases was conducted to identify randomized controlled trials (RCTs) that compared the effects of intravenous lidocaine infusion with placebo or routine care in patients undergoing breast surgery. The primary outcome of interest was the occurrence of chronic post-surgical pain (CPSP) at the longest follow-up. Meta-analyses, incorporating trial sequential analysis, were performed using a random-effects model to assess the overall effect. Results: A total of twelve trials, involving 879 patients, were included in the analysis. Perioperative intravenous lidocaine demonstrated a significant reduction in the incidence of CPSP at the longest follow-up (risk ratio [RR] 0.62, 95% confidence interval [CI] 0.48-0.81; P = 0.0005; I2 = 6%). Trial sequential analysis (TSA) indicated that the cumulative z curve crossed the trial sequential monitoring boundary for benefit, providing sufficient and conclusive evidence. Furthermore, intravenous lidocaine was associated with decreased opioid consumption and a shorter length of hospital stay. Conclusion: Perioperative intravenous lidocaine is effective in relieving acute and CPSP in patients undergoing breast surgery. Systematic review registration: https://inplasy.com/, identifier INPLASY2022100033.

19.
J Control Release ; 360: 304-315, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37356754

RESUMO

Nanomedicines while showing a great potential in improving the performance of chemotherapeutics like docetaxel (DTX) are distressed by a high liver deposition and poor tumor penetration, which might not only cause liver toxicity but also moderate therapeutic effect. Herein, we report that cRGD-directed 24 nm disulfide-crosslinked micellar docetaxel (cRGD-MDTX) presents low liver accumulation, high tumor uptake, and deep tumor penetration, leading to the potent suppression of different solid tumors. cRGD-MDTX was optimized with a cRGD density of 4% and DTX loading of 10 wt%. Interestingly, cRGD-MDTX enabled an extraordinary tumor-liver ratio of 2.8/1 with a DTX uptake of 8.3 %ID/g in αvß3 over-expressing PC3 prostate tumor. The therapeutic studies demonstrated striking antitumor effects of cRGD-MDTX toward PC3 prostate tumor, prostate cancer patient-derived xenografts (PDX), orthotopic A549-Luc lung cancer and orthotopic SKOV3-Luc ovarian tumor models, in which tumor growth was effectually inhibited and 6-8 times better improvement of median survival time over free DTX was observed. This small disulfide-crosslinked micellar drug capable of relegating liver deposition opens a new avenue to nanomedicines for targeted therapy.


Assuntos
Antineoplásicos , Neoplasias Hepáticas , Neoplasias da Próstata , Masculino , Humanos , Docetaxel/uso terapêutico , Micelas , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Dissulfetos , Oligopeptídeos , Linhagem Celular Tumoral , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia
20.
Chemosphere ; 318: 137819, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36640988

RESUMO

Lack of knowledge on the destiny of organic micropollutants (OMPs) in the Tibetan Plateau region of China prevents the public from being aware of the need for protecting these unique aquatic ecosystems that are precious water resources and source areas of the Yellow River. To address this knowledge gap, this study systematically investigated the multi-residue analysis, distribution, and potential risks of six types of OMPs, namely, neonicotinoid pesticides (NEOs), fungicides, organophosphate esters (OPEs), organophosphorus pesticides (OPPs), psychoactive substances (PSs), and antidepressants (ADs), in surface waters of major cities in Qinghai. A total of 31 compounds, consisting of 8 NEOs, 1 fungicide, 12 OPEs, 2 OPPs, 5 PSs, and 3 ADs, were detected in >50% of the sites, showing their ubiquitous nature in the study area. Results showed that the total OMP concentration in surface water was 28.3-908 ng/L, and OPEs were the dominant composition (48.6%-97.4%). The risk quotient values of the detected diazinon and dursban regularly exceeded 1 for aquatic organisms at all sampling sites, indicating moderate-high chronic ecological risk. The joint probability curves showed that dursban and NEOs have higher risk levels than other OMPs. Although the results of the non-carcinogenic total hazard quotient of the OMPs in the surface water was less than 1 in all age groups and the carcinogenic risk was lower than the negligible risk level, the potential risks to children and infants were considerably greater and should not be underestimated. In addition to pollutant concentration and exposure duration, ingestion rate and body weight (BW) are also important factors affecting health risk, with BW having a negative effect. To the best of the authors' knowledge, this report is the first to describe OMP pollution in Qinghai, and the results provide new insight into the ecological security of the water resources of the Tibetan Plateau.


Assuntos
Clorpirifos , Fungicidas Industriais , Praguicidas , Poluentes Químicos da Água , Lactente , Criança , Humanos , Compostos Organofosforados , Ecossistema , Poluentes Químicos da Água/análise , Praguicidas/análise , China , Organofosfatos/análise , Água/análise , Fungicidas Industriais/análise , Monitoramento Ambiental , Medição de Risco
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