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1.
Anal Chem ; 96(23): 9713-9720, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38795036

RESUMO

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder that results in the degeneration of neurons in the brain and spinal cord. Although a substantial number of studies have been conducted, much remains to be learned about the cellular mechanisms underlying ALS. In this study, we employed an engineered ascorbate peroxidase (APEX)-based proximity biotinylation, together with affinity pull-down of the ensuing biotinylated peptides, to investigate the proximity proteomes of human SOD1 and its two ALS-linked mutants, G85R and G93A. We were able to identify 25 common biotinylated peptides with preferential enrichment in the proximity proteomes of SOD1G85R and SOD1G93A over wild-type SOD1. Our coimmunoprecipitation followed by Western blot analyses revealed that one of these proteins, SRSF2, binds more strongly with the two SOD1 mutants than its wild-type counterpart. We also observed aberrant splicing of mRNAs in cells with ectopic expression of the two SOD1 mutants relative to cells expressing the wild-type protein. In addition, the aberrations in splicing elicited by the SOD1 variants were markedly attenuated upon knockdown of SRSF2. Collectively, we uncovered that ALS-liked SOD1G85R and SOD1G93A mutants interact more strongly with SRSF2, where the aberrant interactions perturbed mRNA splicing. Thus, our work offered novel mechanistic insights into the contributions of the ALS-linked SOD1 mutants to disease etiology.


Assuntos
Esclerose Lateral Amiotrófica , Mutação , Splicing de RNA , Fatores de Processamento de Serina-Arginina , Superóxido Dismutase-1 , Fatores de Processamento de Serina-Arginina/metabolismo , Fatores de Processamento de Serina-Arginina/genética , Humanos , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Superóxido Dismutase-1/metabolismo , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células HEK293 , Biotinilação
2.
Angew Chem Int Ed Engl ; 63(2): e202316346, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37983620

RESUMO

Piezocatalytic hydrogen peroxide (H2 O2 ) production is a green synthesis method, but the rapid complexation of charge carriers in piezocatalysts and the difficulty of adsorbing substrates limit its performance. Here, metal-organic cage-coated gold nanoparticles are anchored on graphitic carbon nitride (MOC-AuNP/g-C3 N4 ) via hydrogen bond to serve as the multifunctional sites for efficient H2 O2 production. Experiments and theoretical calculations prove that MOC-AuNP/g-C3 N4 simultaneously optimize three key parts of piezocatalytic H2 O2 production: i) the MOC component enhances substrate (O2 ) and product (H2 O2 ) adsorption via host-guest interaction and hinders the rapid decomposition of H2 O2 on MOC-AuNP/g-C3 N4 , ii) the AuNP component affords a strong interfacial electric field that significantly promotes the migration of electrons from g-C3 N4 for O2 reduction reaction (ORR), iii) holes are used for H2 O oxidation reaction (WOR) to produce O2 and H+ to further promote ORR. Thus, MOC-AuNP/g-C3 N4 can be used as an efficient piezocatalyst to generate H2 O2 at rates up to 120.21 µmol g-1 h-1 in air and pure water without using sacrificial agents. This work proposes a new strategy for efficient piezocatalytic H2 O2 synthesis by constructing multiple active sites in semiconductor catalysts via hydrogen bonding, by enhancing substrate adsorption, rapid separation of electron-hole pairs and preventing rapid decomposition of H2 O2 .

3.
New Phytol ; 237(2): 441-453, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36271620

RESUMO

Leaf structure plays an important role in photosynthesis. However, the causal relationship and the quantitative importance of any single structural parameter to the overall photosynthetic performance of a leaf remains open to debate. In this paper, we report on a mechanistic model, eLeaf, which successfully captures rice leaf photosynthetic performance under varying environmental conditions of light and CO2 . We developed a 3D reaction-diffusion model for leaf photosynthesis parameterised using a range of imaging data and biochemical measurements from plants grown under ambient and elevated CO2 and then interrogated the model to quantify the importance of these elements. The model successfully captured leaf-level photosynthetic performance in rice. Photosynthetic metabolism underpinned the majority of the increased carbon assimilation rate observed under elevated CO2 levels, with a range of structural elements making positive and negative contributions. Mesophyll porosity could be varied without any major outcome on photosynthetic performance, providing a theoretical underpinning for experimental data. eLeaf allows quantitative analysis of the influence of morphological and biochemical properties on leaf photosynthesis. The analysis highlights a degree of leaf structural plasticity with respect to photosynthesis of significance in the context of attempts to improve crop photosynthesis.


Assuntos
Oryza , Oryza/metabolismo , Células do Mesofilo/metabolismo , Dióxido de Carbono/metabolismo , Folhas de Planta/metabolismo , Fotossíntese
4.
Environ Sci Technol ; 57(9): 4014-4026, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36811826

RESUMO

CH4 emissions from inland waters are highly uncertain in the current global CH4 budget, especially for streams, rivers, and other lotic systems. Previous studies have attributed the strong spatiotemporal heterogeneity of riverine CH4 to environmental factors such as sediment type, water level, temperature, or particulate organic carbon abundance through correlation analysis. However, a mechanistic understanding of the basis for such heterogeneity is lacking. Here, we combine sediment CH4 data from the Hanford reach of the Columbia River with a biogeochemical-transport model to show that vertical hydrologic exchange flows (VHEFs), driven by the difference between river stage and groundwater level, determine CH4 flux at the sediment-water interface. CH4 fluxes show a nonlinear relationship with the magnitude of VHEFs, where high VHEFs introduce O2 into riverbed sediments, which inhibit CH4 production and induce CH4 oxidation, and low VHEFs cause transient reduction in CH4 flux (relative to production) due to reduced advective CH4 transport. In addition, VHEFs lead to the hysteresis of temperature rise and CH4 emissions because high river discharge caused by snowmelt in spring leads to strong downwelling flow that offsets increasing CH4 production with temperature rise. Our findings reveal how the interplay between in-stream hydrologic flux besides fluvial-wetland connectivity and microbial metabolic pathways that compete with methanogenic pathways can produce complex patterns in CH4 production and emission in riverbed alluvial sediments.


Assuntos
Carbono , Metano , Metano/análise , Rios , Agricultura , Água , Dióxido de Carbono/análise
5.
Cell Mol Biol (Noisy-le-grand) ; 69(10): 160-165, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37953568

RESUMO

Colorectal cancer (CRC) ranks third in cancer incidence and second in cancer mortality globally. MicroRNAs (miRNAs) are promising biomarkers and therapeutic targets for CRC diagnosis and treatment. The miR-155 is reported to induce radiation resistance in CRC. In this study, we aimed to further clarify the role and underlying mechanism of the miR-155 in CRC cell malignancy. We found that miR-155 was significantly up-regulated in CRC tissues. The results of loss-of-function experiments revealed that miR-155 deficiency suppressed the proliferative capacity, invasion, and migration of CRC cells. Moreover, the downstream target genes of miR-155 were screened, and miR-155 was demonstrated to directly bind to FOXO3a in CRC cells to negatively regulate FOXO3a expression. FOXO3a was downregulated in CRC tissues and the expression of FOXO3a and miR-155 was in negative correlation in CRC tissues. FOXO3a overexpression alone was revealed to inhibit CRC cell growth, migration and invasion. Additionally, rescue assays showed that FOXO3a silencing significantly reversed the inhibitory effect of miR-155 deficiency on CRC cell malignant behaviors. In conclusion, miR-155 induces malignant phenotypes of CRC cells including cell proliferation, migration and invasion by targeting FOXO3a, which might provide clues for the targeted therapy of CRC.


Assuntos
Neoplasias Colorretais , Proteína Forkhead Box O3 , MicroRNAs , Humanos , Carcinogênese/genética , Carcinógenos , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Invasividade Neoplásica/patologia , Proteína Forkhead Box O3/genética
6.
Molecules ; 28(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37049734

RESUMO

A two-dimensional (2D) polar monolayer with a polarization electric field can be used as a potential photocatalyst. In this work, first principle calculations were used to investigate the stability and photocatalytic properties of 2D polar monolayer SiTe as a potential promising catalyst in water-splitting. Our results show that the 2D polar monolayer SiTe possesses an indirect band gap of 2.41 eV, a polarization electric field from the (001) surface to the (001¯) surface, a wide absorption region, and a suitable band alignment for photocatalytic water-splitting. We also discovered that the photocatalytic activity of 2D polar monolayer SiTe could be effectively tuned through strain engineering. Additionally, strain engineering, particularly compressive strain in the range from -1% to -3%, can enhance the photocatalytic activity of 2D polar monolayer SiTe. Overall, our findings suggest that 2D polar monolayer SiTe has the potential to be a promising catalyst for photocatalytic water-splitting using visible light.

7.
J Hum Genet ; 67(4): 183-195, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34690349

RESUMO

To compare single-molecule real-time technology (SMRT) and conventional genetic diagnostic technology of rare types of thalassemia mutations, and to analyze the molecular characteristics and phenotypes of rare thalassemia gene variants, we used 434 cases with positive hematology screening as the cohort, then used SMRT technology and conventional gene diagnosis technology [(Gap-PCR, multiple ligation probe amplification technology (MLPA), PCR-reverse dot blot (RDB)] for thalassemia gene screening. Among the 434 enrolled cases, conventional technology identified 318 patients with variants (73.27%) and 116 patients without variants (26.73%), SMRT identified 361 patients with variants (83.18%), and 73 patients without variants (16.82%). The positive detection rate of SMRT was 9.91% higher than conventional technology. Combination of the two methods identified 485 positive alleles among 49 types of variant. The genotypes of 354 cases were concordant between the two methods, while 80 cases were discordant. Among the 80 cases, 76 cases had variants only identified in SMRT method, 3 cases had variants only identified in conventional method, and 1 false positive result by the traditional PCR detection technology. Except the three variants in HS40 and HBG1-HBG2 loci, which was beyond the design of SMRT method in this study, all the other discordant variants identified by SMRT were validated by further Sanger sequencing or MLPA. The hematological phenotypic parameters of 80 discordant cases were also analyzed. SMRT technology increased the positive detection rate of thalassemia genes, and detected rare thalassemia cases with variable phenotypes, which had great significance for clinical thalassemia gene screening.


Assuntos
Talassemia alfa , Talassemia beta , China , Estudos de Associação Genética , Genótipo , Humanos , Mutação , Fenótipo , Tecnologia , Talassemia alfa/diagnóstico , Talassemia alfa/genética , Talassemia beta/diagnóstico
8.
Phys Chem Chem Phys ; 24(48): 29570-29578, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36448558

RESUMO

Polarized structured nitride semiconductors are attractive due to their unique and environment-friendly electronic properties. The stability, ferroelectricity and photocatalytic and photovoltaic properties of super-wurtzite Mg2XN3 (X = Bi, Mo, Nb, Sb, Ta, Tc and W) were determined based on first principles calculations in this study. The calculated results indicate that Mg2XN3 (X = Sb, Ta, Bi and Nb) are stable polar nitrides by phonon frequencies, elastic coefficients and ferroelectric analysis. Mg2XN3 (X = Sb, Ta and Nb) with large ferroelectric polarization strength could absorb ultraviolet light to promote photocatalytic water splitting for hydrogen production. Mg2BiN3 is a new excellent photovoltaic candidate due to its ideal energy band, high electron mobility, high absorption coefficient and large ferroelectric polarization strength.

9.
Plant Cell Environ ; 44(5): 1436-1450, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33410527

RESUMO

The Farquhar-von Caemmerer-Berry (FvCB) model is extensively used to model photosynthesis from gas exchange measurements. Since its publication, many methods have been developed to measure, or more accurately estimate, parameters of this model. Here, we have created a tool that uses Bayesian statistics to fit photosynthetic parameters using concurrent gas exchange and chlorophyll fluorescence measurements whilst evaluating the reliability of the parameter estimation. We have tested this tool on synthetic data and experimental data from rice leaves. Our results indicate that reliable parameter estimation can be achieved whilst only keeping one parameter, Km , that is, Michaelis constant for CO2 by Rubisco, prefixed. Additionally, we show that including detailed low CO2 measurements at low light levels increases reliability and suggests this as a new standard measurement protocol. By providing an estimated distribution of parameter values, the tool can be used to evaluate the quality of data from gas exchange and chlorophyll fluorescence measurement protocols. Compared to earlier model fitting methods, the use of a Bayesian statistics-based tool minimizes human interaction during fitting, reducing the subjectivity which is essential to most existing tools. A user friendly, interactive Bayesian tool script is provided.


Assuntos
Carbono/metabolismo , Oryza/fisiologia , Fotossíntese/fisiologia , Folhas de Planta/fisiologia , Incerteza , Teorema de Bayes , Dióxido de Carbono/metabolismo , Clorofila/metabolismo , Fluorescência , Luz , Oryza/efeitos da radiação , Fotossíntese/efeitos da radiação , Folhas de Planta/efeitos da radiação
10.
Cytogenet Genome Res ; 160(11-12): 634-642, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33756471

RESUMO

High-throughput sequencing based on copy number variation (CNV-seq) is commonly used to detect chromosomal abnormalities. This study identifies chromosomal abnormalities in aborted embryos/fetuses in early and middle pregnancy and explores the application value of CNV-seq in determining the causes of pregnancy termination. High-throughput sequencing was used to detect chromosome copy number variations (CNVs) in 116 aborted embryos in early and middle pregnancy. The detection data were compared with the Database of Genomic Variants (DGV), the Database of Chromosomal Imbalance and Phenotype in Humans using Ensemble Resources (DECIPHER), and the Online Mendelian Inheritance in Man (OMIM) database to determine the CNV type and the clinical significance. High-throughput sequencing results were successfully obtained in 109 out of 116 specimens, with a detection success rate of 93.97%. In brief, there were 64 cases with abnormal chromosome numbers and 23 cases with CNVs, in which 10 were pathogenic mutations and 13 were variants of uncertain significance. An abnormal chromosome number is the most important reason for embryo termination in early and middle pregnancy, followed by pathogenic chromosome CNVs. CNV-seq can quickly and accurately detect chromosome abnormalities and identify microdeletion and microduplication CNVs that cannot be detected by conventional chromosome analysis, which is convenient and efficient for genetic etiology diagnosis in miscarriage.


Assuntos
Variações do Número de Cópias de DNA/genética , Perda do Embrião/genética , Perda do Embrião/patologia , Testes Genéticos , Análise de Sequência de DNA , Adulto , Perda do Embrião/diagnóstico , Feminino , Humanos , Idade Materna , Gravidez
11.
Hemoglobin ; 44(1): 51-54, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31933393

RESUMO

The aim of this study was to identify the rare thalassemia genotype in a family and perform prenatal diagnosis (PND) on the proband's unborn child. Peripheral blood was collected from the family members for hematology analysis and capillary electrophoresis (CE) analysis. Peripheral blood and cord blood were analyzed by gap-polymerase chain reaction (gap-PCR), reverse dot-blot and Sanger sequencing for genotypes of α-thalassemia (α-thal). A heterozygous mutation, HBA2: c.1A>G, was identified in the proband and his father. Two compound heterozygous variants, HBA2: c.1A>G and the - -SEA (Southeast Asian) deletion, were revealed in the proband's unborn child. The hemoglobin (Hb) CE result of the fetal cord blood indicated the fetus had Hb H disease. We have identified a rare thalassemia mutation (HBA2: c.1A>G) in a Chinese family and enriched the rare α-thal gene pool in the Chinese population. When the patient's phenotype does not match the genotype detected by thalassemia gene detection kits, further investigation of rare genotypes should be conducted to avoid missed diagnosis or misdiagnosis, which can help guide clinical diagnosis, population screening and genetic counseling.


Assuntos
Hemoglobina A2/genética , Hemoglobina H/genética , Mutação , Diagnóstico Pré-Natal , alfa-Globinas/genética , Talassemia alfa/diagnóstico , Talassemia alfa/genética , Adulto , Povo Asiático , Sequência de Bases , Feminino , Feto , Expressão Gênica , Aconselhamento Genético , Genótipo , Heterozigoto , Humanos , Masculino , Linhagem , Fenótipo , Análise de Sequência de DNA , Talassemia alfa/etnologia , Talassemia alfa/patologia
12.
Hemoglobin ; 44(5): 329-333, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32811243

RESUMO

The aim of this study was to investigate a family with nonhomologous sequence recombination of HBA1 and HBA2 genes and provide a favorable basis for genetic counseling and eugenics. Peripheral blood of family members was collected. Hematological parameters were determined by an automated cell counter and hemoglobin (Hb) analysis was performed using high performance liquid chromatography (HPLC). Villus samples were taken for prenatal diagnosis (PND). Gap-polymerase chain reaction (gap-PCR) and reverse dot-blot were used for thalassemia genotyping. DNA sequencing was used to analyze the gene sequence of HBA1 (α1-globin) and HBA2 (α2-globin). The nonhomologous sequence recombination allelic variant of HBA1 and HBA2 genes were identified, namely, a gene conversion on the HBA2 gene called α12 (HBA12). The α12 allele consists primarily of the HBA2 gene sequence except for a segment of the IVS-II in which HBA2-specific sequences have been replaced by HBA1-specific sequences. The following genotypes were observed: - -SEA/αα12 (Southeast Asian deletion), αα/αα12 and αQSα/αα12 (Hb Quong Sze or Hb QS; HBA2: c.377T>C), and all manifested as small cell hypochromic anemia. To find the α12 allele in the Chinese population and clarify the influence of the α12 allele and its common inheritance with abnormal Hb and α-thalassemia (α-thal) on α-globin gene expression can help guide clinical diagnosis and genetic counseling.


Assuntos
Linhagem , Recombinação Genética , alfa-Globinas/genética , Talassemia alfa/diagnóstico , Talassemia alfa/genética , Alelos , Cromatografia Líquida de Alta Pressão , Índices de Eritrócitos , Feminino , Genótipo , Humanos , Masculino , Mutação , Gravidez , Locos de Características Quantitativas , Análise de Sequência de DNA , Talassemia alfa/sangue
15.
Front Biosci (Landmark Ed) ; 29(4): 143, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38682186

RESUMO

Coenzyme A (CoA) functions as a crucial carrier of acyl groups within cells, playing a fundamental role in regulating acyl transfer reactions and participating in cellular metabolic processes. As the principal substrate and cofactor engaged in diverse metabolic reactions, CoA and its derivatives exert central influence over various physiological processes, primarily modulating lipid and ketone metabolism, as well as protein modification. This paper presents a comprehensive review of the molecular mechanisms by which CoA influences the onset and progression of cancer, cardiovascular disease (CVD), neurodegenerative disorders, and other illnesses. The main focal points include the following. (1) In cancer, enzymes such as acetyl-CoA synthetase 2, ATP citrate lyase, and acetyl-CoA carboxylase regulate lipid synthesis and energy metabolism by modulating acetyl-CoA levels. (2) In CVD, the effects of enzymes such as stearoyl-CoA desaturase-1, 3-hydroxy-3-methylglutaryl-CoA (HMGC) synthase 2, and HMGC reductase on the formation and advancement of these diseases are elucidated by their regulation of CoA metabolism across multiple organs. (3) In neurodegenerative disorders, the significance of CoA in maintaining cholesterol homeostasis in the brain and its implications on the development of such disorders are thoroughly discussed. The metabolic processes involving CoA and its derivatives span all physiological aspects within cells, playing a critical role in the onset and progression of various diseases. Elucidating the role of CoA in these conditions yields important insights that can serve as valuable references and guidance for disease diagnosis, treatment, and drug development.


Assuntos
Doenças Cardiovasculares , Coenzima A , Neoplasias , Doenças Neurodegenerativas , Humanos , Doenças Neurodegenerativas/metabolismo , Neoplasias/metabolismo , Coenzima A/metabolismo , Doenças Cardiovasculares/metabolismo , Animais
16.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(2): 520-524, 2024 Apr.
Artigo em Zh | MEDLINE | ID: mdl-38660861

RESUMO

OBJECTIVE: To investigate two cases of rare pathogenic genes, initiation codon mutations in HBA2 gene, combined with Southeast Asian deletion and their family members to understand the relationship of HBA2:c.2T>C and HBA2:c.2delT mutations with clinical phenotype. METHODS: The peripheral blood of family members was obtained for blood cell analysis and capillary electrophoresis hemoglobin analysis. Gap-PCR and reverse dot blotting (RDB) were used to detect common types of mutations in ɑ-thalassaemia gene. Sanger sequencing was used to analyze HBA1 and HBA2 gene sequence. RESULTS: Two proband genotypes were identified as --SEA/αα with HBA2:c.2T>C and --SEA/αα with HBA2:c.2delT. HBA2:c.2T>C/WT and HBA2:c.2delT/WT was detected in family members. They all presented with microcytic hypochromic anemia. CONCLUSION: When HBA2:c.2T>C and HBA2:c.2delT are heterozygous that can lead to static α-thalassemia phenotype, and when combined with mild α-thalassemia, they can lead to the clinical manifestations of hemoglobin H disease. This study provides a basis for genetic counseling.


Assuntos
Genótipo , Mutação , Talassemia alfa , Humanos , Talassemia alfa/genética , Anemia Hipocrômica/genética , Hemoglobina A2/genética , Hemoglobina H/genética , Heterozigoto , Fenótipo
17.
NPJ Regen Med ; 9(1): 12, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499577

RESUMO

Regeneration in the injured spinal cord is limited by physical and chemical barriers. Acute implantation of a multichannel poly(lactide-co-glycolide) (PLG) bridge mechanically stabilizes the injury, modulates inflammation, and provides a permissive environment for rapid cellularization and robust axonal regrowth through this otherwise inhibitory milieu. However, without additional intervention, regenerated axons remain largely unmyelinated (<10%), limiting functional repair. While transplanted human neural stem cells (hNSC) myelinate axons after spinal cord injury (SCI), hNSC fate is highly influenced by the SCI inflammatory microenvironment, also limiting functional repair. Accordingly, we investigated the combination of PLG scaffold bridges with hNSC to improve histological and functional outcome after SCI. In vitro, hNSC culture on a PLG scaffold increased oligodendroglial lineage selection after inflammatory challenge. In vivo, acute PLG bridge implantation followed by chronic hNSC transplantation demonstrated a robust capacity of donor human cells to migrate into PLG bridge channels along regenerating axons and integrate into the host spinal cord as myelinating oligodendrocytes and synaptically integrated neurons. Axons that regenerated through the PLG bridge formed synaptic circuits that connected the ipsilateral forelimb muscle to contralateral motor cortex. hNSC transplantation significantly enhanced the total number of regenerating and myelinated axons identified within the PLG bridge. Finally, the combination of acute bridge implantation and hNSC transplantation exhibited robust improvement in locomotor recovery. These data identify a successful strategy to enhance neurorepair through a temporally layered approach using acute bridge implantation and chronic cell transplantation to spare tissue, promote regeneration, and maximize the function of new axonal connections.

18.
Front Neurorobot ; 17: 1205370, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37614968

RESUMO

Deep neural networks (DNNs) have been shown to be susceptible to critical vulnerabilities when attacked by adversarial samples. This has prompted the development of attack and defense strategies similar to those used in cyberspace security. The dependence of such strategies on attack and defense mechanisms makes the associated algorithms on both sides appear as closely processes, with the defense method being particularly passive in these processes. Inspired by the dynamic defense approach proposed in cyberspace to address endless arm races, this article defines ensemble quantity, network structure, and smoothing parameters as variable ensemble attributes and proposes a stochastic ensemble strategy based on heterogeneous and redundant sub-models. The proposed method introduces the diversity and randomness characteristic of deep neural networks to alter the fixed correspondence gradient between input and output. The unpredictability and diversity of the gradients make it more difficult for attackers to directly implement white-box attacks, helping to address the extreme transferability and vulnerability of ensemble models under white-box attacks. Experimental comparison of ASR-vs.-distortion curves with different attack scenarios under CIFAR10 preliminarily demonstrates the effectiveness of the proposed method that even the highest-capacity attacker cannot easily outperform the attack success rate associated with the ensemble smoothed model, especially for untargeted attacks.

19.
J Hematop ; 16(2): 95-101, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38175446

RESUMO

Hereditary spherocytosis (HS) is a common, hereditary hemolytic anemia (HHA) that is attributed to the disturbance of five erythrocyte membrane proteins. HS is also common in Guangxi, China. Target region capture high-throughput sequencing technology was used to analyze genetic mutations found in HS patients. Pedigree analysis was also performed, in some cases, to provide an optimized approach for the etiological diagnosis of complex, hereditary hemolytic anemia. Blood samples from the probands and their families were assessed by laboratory tests, target region capture high-throughput sequencing technology, and Sanger sequencing. We detected 79 HS patients from 37 unrelated families. The mutations observed in these patients were found mainly in four HS-related genes. These included SLC4A1, which was mutated in 31.65% of patients (25/79), SPTA1 (30.78% (24/79)), EPB42 (6.33% (5/79)), and SPTB (5.06% (4/79)). Composite genotype was observed in 26.58% (21/79) of patients and included mutations in two or more HS-related genes or mutations in HS-related genes combined with thalassemia or G6PD deficiency. No significant differences in clinical symptoms were found among patients of various genotypes except total bilirubin. Mean reticulocyte volume (MRV) and mean sphered cell volume (MSCV) of the composite genotype were significantly different from other groups. A total of 28 mutation types were found in HS-related genes. Using high-throughput sequencing technology, we also found some cases that had been misdiagnosed. MRV and MSCV are more significant in compound mutations as sensitive determinants of HS. High-throughput sequencing technology can be used to provide a more effective etiological diagnostic method for HS, with high efficiency and specificity.


Assuntos
Anemia Hemolítica Congênita , Esferocitose Hereditária , Humanos , China/epidemiologia , Esferocitose Hereditária/genética , Genótipo , Mutação
20.
Nat Commun ; 14(1): 1342, 2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36906625

RESUMO

Encapsulation engineering is an effective strategy to improve the stability of perovskite solar cells. However, current encapsulation materials are not suitable for lead-based devices because of their complex encapsulation processes, poor thermal management, and inefficient lead leakage suppression. In this work, we design a self-crosslinked fluorosilicone polymer gel, achieving nondestructive encapsulation at room temperature. Moreover, the proposed encapsulation strategy effectively promotes heat transfer and mitigates the potential impact of heat accumulation. As a result, the encapsulated devices maintain 98% of the normalized power conversion efficiency after 1000 h in the damp heat test and retain 95% of the normalized efficiency after 220 cycles in the thermal cycling test, satisfying the requirements of the International Electrotechnical Commission 61215 standard. The encapsulated devices also exhibit excellent lead leakage inhibition rates, 99% in the rain test and 98% in the immersion test, owing to excellent glass protection and strong coordination interaction. Our strategy provides a universal and integrated solution for achieving efficient, stable, and sustainable perovskite photovoltaics.

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