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1.
Environ Res ; 262(Pt 1): 119853, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39218337

RESUMO

Environmental persistent free radicals (EPFRs), as emerging contaminants in environment, can induce oxidative stress causing severe adverse health outcomes. The formation of EPFRs is thought to be associated with the transformation of aromatic compounds like polycyclic aromatic hydrocarbons (PAHs). Herein this study firstly evaluated EPFRs in industrial soils being highly polluted by PAHs, and explored its associated with PAHs, with the modification of soil organic matter content. Soil EPFRs from two industrial plants were 4.1 × 1016 and 4.5 × 1016 spins/g, respectively, that were significantly higher than the levels in the surrounding areas. Carbon-centered EPFRs account for approximately 80% inside the plant, but outside the plants, nearly 50-70% of EPFRs were carbon-centered with adjacent heteroatoms. As one important precursor of EPFRs, PAHs exhibited a significantly positive correlation with EPFRs in industrial soils (p < 0.05), explaining 40%-60% of the variation in EPFRs concentration in the present study. The relationship between soil organic matter and EPFRs concentration normalized by PAHs forms an inverted V-shape, suggesting an inhibition effect of soil organic matter on the EPFR formation potentials from PAHs, that is worthy to be further examed in future laboratory and field experiments.

2.
Sci Rep ; 14(1): 19289, 2024 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-39164381

RESUMO

Plants are affected by many environmental factors during their various stages of growth, among which salt stress is a key factor. WRKY transcription factors play important roles in the response to stress in plants. In this study, SmWRKY40 from eggplant (Solanum melongena L.) was found to belong to the subfamily of WRKY transcription factor group II, closely related to the evolution of wild tomato ScWRKY40 (Solanum chilense). The expression of SmWRKY40 could be induced by several abiotic stresses (drought, salt, and high temperature) and ABA to different degrees, with salt stress being the most significant. In Arabidopsis thaliana, the seed germination rate of SmWRKY40 overexpression seedlings was significantly higher than those of the wild type under high concentrations of NaCl and ABA, and root elongation of overexpression lines was also longer than wild type under NaCl treatments. SmWRKY40 overexpression lines were found to enhance Arabidopsis tolerance to salt with lower ROS, MDA, higher soluble protein, proline accumulation, and more active antioxidant enzymes. The expression level of genes related to stress and ABA signaling displayed significant differences in SmWRKY40 overexpression line than that of WT. These results indicate that SmWRKY40 regulates ABA and salt stress responses in Arabidopsis.


Assuntos
Ácido Abscísico , Arabidopsis , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Estresse Salino , Solanum melongena , Fatores de Transcrição , Solanum melongena/genética , Solanum melongena/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácido Abscísico/metabolismo , Plantas Geneticamente Modificadas , Estresse Fisiológico , Tolerância ao Sal/genética , Germinação/genética , Filogenia , Plântula/genética , Plântula/metabolismo , Plântula/crescimento & desenvolvimento
3.
Neurol Sci ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39088158

RESUMO

OBJECTIVE: To investigate the efficacy of transcranial ultrasound stimulation (TUS) combined with Fastigial nucleus stimulation (FNS) on cerebral blood flow and limb function in patients in the acute phase of ischemic stroke. METHODS: A total of 90 patients in the acute phase of ischemic stroke were randomly divided into an FNS, TUS, and TUS + FNS group (30 patients each), and all patients also received conventional treatment. The FNS group was treated with FNS alone. The TUS group was treated with TUS alone. The TUS + FNS group was treated with both TUS and FNS. The three groups were treated once a day for 6 days a week. RESULTS: The simplified Fugl-Meyer Assessment (FMA) and Barthel index scores (BI), and the peak systolic blood flow velocity (Vs) and the mean blood flow velocity (Vm) of the anterior cerebral artery, middle cerebral artery, and posterior cerebral artery, were significantly higher in all three groups compared with before treatment (P < 0.05). The scores for the TUS group were higher than for the FNS group (P < 0.05), and the scores of the TUS + FNS group were higher than the TUS and FNS groups, respectively (P < 0.05). The total effective rate was 63.3%, 70.0%, and 90.0% in the FNS, TUS, and TUS + FNS groups, respectively, and the difference between the three groups was statistically significant (P < 0.05). CONCLUSION: The FNS and TUS treatments improved the function of and accelerated cerebral blood flow in patients with acute ischemic stroke to different degrees, and the combined use of both treatment types was overall more effective.

4.
J Craniofac Surg ; 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39178415

RESUMO

OBJECTIVE: In children with giant cystic solid craniopharyngioma (CP), the Ommaya reservoir was implanted in the CP cavity, and the cystic fluid was continuously drained for 5 days before the tumor resection. METHODS: An 11-year-old male patient was admitted to the hospital due to vision loss for 1 year, intermittent headache, vomiting for 6 months, and frequent urination for 2 months. Besides, magnetic resonance imaging of the head showed cystic solid lesions in the sellar region, suprasellar, and bilateral frontal lobes, with a size of 96.0×82.6×76.0 mm. Before the surgical resection, an Ommaya reservoir was implanted within the tumor cavity. The drainage was continued for 5 days and was 39 to 50 mL (43.80 ± 4.67 mL). Following the tumor shrank, a craniotomy was performed. RESULTS: Following surgical treatment, the CP was entirely removed. The child subsequently developed hypothyroidism and hypocortisolism, for which hormone replacement therapy was administered. No tumor recurrence was observed after 3 years of follow-up. CONCLUSION: The treatment of giant cystic solid CP in children is challenging. Preoperative implantation of the Ommaya reservoir, continuous drainage of cystic fluid, shrinkage of the tumor, and reduction of tumor tension are beneficial for tumor resection.

5.
J Clin Invest ; 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39146021

RESUMO

Strategies beyond hormone-related therapy should need to be developed to improve prostate cancer mortalityfor better disease management. Here we show that FUBP1 and its methylation are essential for prostate cancer progression, and a competitive peptide interfering with FUBP1 methylation suppresses the development of prostate cancer. FUBP1 accelerated prostate cancer development across in various pre-clinical models. PRMT5-mediated FUBP1 methylation, regulated by BRD4, was crucial for its oncogenic effect and correlated with earlier biochemical recurrence shorter treatment durations in our patient cohort. Suppressed prostate cancer progression was observed in different various genetic mouse models expressing FUBP1 mutants deficient in PRMT5-mediated methylation. A competitive peptide, which was delivered through nanocomplexes, successfully disrupted the interaction of FUBP1 with PRMT5, blocked FUBP1 methylation, and inhibited prostate cancer development in different various pre-clinical models. Overall, our findings suggest that targeting FUBP1 methylation provides a potentially therapeutic strategy for disease prostate cancer management.

6.
BMC Infect Dis ; 24(1): 770, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090540

RESUMO

BACKGROUND: The GeneXpert MTB/RIF (Xpert) assay is a widely used technology for detecting Mycobacterium tuberculosis (MTB) in clinical samples. However, the study on the failure of the Xpert assay during routine implementation and its potential solutions is limited. METHODS: We retrospectively analyzed the records of unsuccessful tests in the Xpert and the GeneXpert MTB/RIF Ultra (Ultra) assays between April 2017 and April 2021 at the Shanghai Public Health Clinical Center. To further investigate the effect of prolonged preprocessing on clinical sputum, an additional 120 sputum samples were collected for Xpert testing after 15 min, 3 h, and 6 h preprocessing. The analysis was performed by SPSS version 19.0 software. RESULTS: A total of 11,314 test records were analyzed, of which 268 (2.37%) had unsuccessful test results. Among these, 221 (1.95%) were reported as "Error", 43 (0.38%) as "Invalid", and 4 (0.04%) as "No result". The most common clinical specimen for Xpert tests was sputum, accounting for 114 (2.17%) unsuccessful tests. The failure rate of urine specimens was lower than that of sputum (OR = 0.12, 95% CI: 0.02-0.88, χ2 = 6.22, p = 0.021). In contrast, the failure rate of stool specimens was approximately twice as high as that of sputum (OR = 1.93, 95% CI: 1.09-3.40, χ2 = 5.35, p = 0.014). In the prolonged preprocessing experiment, 102 cases (85%) yielded consistent results in Xpert tests. Furthermore, 7 cases (5.83%) detected an increase in MTB load, 8 cases (6.67%) detected a decrease in MTB load, and 3 cases (2.5%) yielded incongruent results in MTB and rifampicin resistance detection. CONCLUSIONS: The primary cause of unsuccessful tests in the Xpert assay was reported as "Error". Despite varying failure rates depending on the samples, the Xpert assay can be applied to extrapulmonary samples. For paucibacillary specimens, retesting the remaining preprocessed mixture should be carefully considered.


Assuntos
Mycobacterium tuberculosis , Escarro , Humanos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Escarro/microbiologia , Estudos Retrospectivos , China , Manejo de Espécimes/métodos , Técnicas de Diagnóstico Molecular/métodos , Tuberculose/diagnóstico , Tuberculose/microbiologia , Rifampina/farmacologia , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/microbiologia , Masculino , Feminino
7.
ACS Nano ; 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39022809

RESUMO

Living organisms use ions and small molecules as information carriers to communicate with the external environment at ultralow power consumption. Inspired by biological systems, artificial ion-based devices have emerged in recent years to try to realize efficient information-processing paradigms. Nanofluidic ionic memristors, memory resistors based on confined fluidic systems whose internal ionic conductance states depend on the historical voltage, have attracted broad attention and are used as neuromorphic devices for computing. Despite their high exposure, nanofluidic ionic memristors are still in the initial stage. Therefore, systematic guidance for developing and reasonably designing ionic memristors is necessary. This review systematically summarizes the history, mechanisms, and potential applications of nanofluidic ionic memristors. The essential challenges in the field and the outlook for the future potential applications of nanofluidic ionic memristors are also discussed.

8.
Chaos ; 34(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38980380

RESUMO

Neural networks are popular data-driven modeling tools that come with high data collection costs. This paper proposes a residual-based multipeaks adaptive sampling (RMAS) algorithm, which can reduce the demand for a large number of samples in the identification of stochastic dynamical systems. Compared to classical residual-based sampling algorithms, the RMAS algorithm achieves higher system identification accuracy without relying on any hyperparameters. Subsequently, combining the RMAS algorithm and neural network, a few-shot identification (FSI) method for stochastic dynamical systems is proposed, which is applied to the identification of a vegetation biomass change model and the Rayleigh-Van der Pol impact vibration model. We show that the RMAS algorithm modifies residual-based sampling algorithms and, in particular, reduces the system identification error by 76% with the same sample sizes. Moreover, the surrogate model accurately predicts the first escape probability density function and the P bifurcation behavior in the systems, with the error of less than 1.59×10-2. Finally, the robustness of the FSI method is validated.

9.
EMBO Mol Med ; 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39085398

RESUMO

Small-cell lung cancer (SCLC) is the most aggressive and lethal type of lung cancer, characterized by limited treatment options, early and frequent metastasis. However, the determinants of metastasis in SCLC are poorly defined. Here, we show that estrogen-related receptor gamma (ERRγ) is overexpressed in metastatic SCLC tumors, and is positively associated with SCLC progression. ERRγ functions as an essential activator of extracellular matrix (ECM) remodeling and cell adhesion, two critical steps in metastasis, by directly regulating the expression of major genes involved in these processes. Genetic and pharmacological inhibition of ERRγ markedly reduces collagen production, cell-matrix adhesion, microfilament production, and eventually blocks SCLC cell invasion and tumor metastasis. Notably, ERRγ antagonists significantly suppressed tumor growth and metastasis and restored SCLC vulnerability to chemotherapy in multiple cell-derived and patient-derived xenograft models. Taken together, these findings establish ERRγ as an attractive target for metastatic SCLC and provide a potential pharmacological strategy for treating this lethal disease.

10.
BMC Plant Biol ; 24(1): 705, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39054416

RESUMO

BACKGROUND: Drought stress limits significantly the crop productivity. However, plants have evolved various strategies to cope with the drought conditions by adopting complex molecular, biochemical, and physiological mechanisms. Members of the nuclear factor Y (NF-Y) transcription factor (TF) family constitute one of the largest TF classes and are involved in plant responses to abiotic stresses. RESULTS: TaNF-YB2, a NY-YB subfamily gene in T. aestivum, was characterized in this study focusing on its role in mediating plant adaptation to drought stress. Yeast two-hybrid (Y-2 H), biomolecular fluoresence complementation (BiFC), and Co-immunoprecipitation (Co-IP) assays indicated that TaNF-YB2 interacts with the NF-YA member TaNF-YA7 and NF-YC family member TaNF-YC7, which constitutes a heterotrimer TaNF-YB2/TaNF-YA7/TaNF-YC7. The TaNF-YB2 transcripts are induced in roots and aerial tissues upon drought signaling; GUS histochemical staining analysis demonstrated the roles of cis-regulatory elements ABRE and MYB situated in TaNF-YB2 promoter to contribute to target gene response to drought. Transgene analysis on TaNF-YB2 confirmed its functions in regulating drought adaptation via modulating stomata movement, osmolyte biosynthesis, and reactive oxygen species (ROS) homeostasis. TaNF-YB2 possessed the abilities in transcriptionally activating TaP5CS2, the P5CS family gene involving proline biosynthesis and TaSOD1, TaCAT5, and TaPOD5, the genes encoding antioxidant enzymes. Positive correlations were found between yield and the TaNF-YB2 transcripts in a core panel constituting 45 wheat cultivars under drought condition, in which two types of major haplotypes including TaNF-YB2-Hap1 and -Hap2 were included, with the former conferring more TaNF-YB2 transcripts and stronger plant drought tolerance. CONCLUSIONS: TaNF-YB2 is transcriptional response to drought stress. It is an essential regulator in mediating plant drought adaptation by modulating the physiological processes associated with stomatal movement, osmolyte biosynthesis, and reactive oxygen species (ROS) homeostasis, depending on its role in transcriptionally regulating stress response genes. Our research deepens the understanding of plant drought stress underlying NF-Y TF family and provides gene resource in efforts for molecular breeding the drought-tolerant cultivars in T. aestivum.


Assuntos
Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Fatores de Transcrição , Triticum , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Triticum/genética , Triticum/fisiologia , Triticum/metabolismo , Estresse Fisiológico/genética , Adaptação Fisiológica/genética , Genes de Plantas , Resistência à Seca
12.
Materials (Basel) ; 17(12)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38930166

RESUMO

Cyclic heat treatment is an effective approach for enhancing the mechanical properties of 18Ni(C250) maraging steel, and the selection of cyclic heat treatment temperature is a key factor. In this study, a cyclic heat treatment process with a two-step solution treatment is employed to investigate the influence of cyclic heat treatment temperature, specifically the first solution treatment temperature (920 °C, 950 °C, and 980 °C), on the microstructure and mechanical properties of 18Ni(C250) maraging steel. The results indicate that with an increase in the cyclic heat treatment temperature, the average grain size of the 18Ni(C250) maraging steel decreases initially and then increases. When the cyclic heat treatment temperature reaches 950 °C, the grain size is at its minimum, exhibiting optimal grain uniformity. Additionally, the increase in cyclic heat treatment temperature results in a reduction in the size of martensitic lath with the same orientation inside the grains, along with an increase in the relative quantity of low-angle grain boundaries. Furthermore, the volume fraction and size of retained austenite show a monotonous increase with the rise in the temperature of the cyclic heat treatment, and the rate of increase becomes notably larger when the temperature is raised from 950 °C to 980 °C. Based on the observed microstructural changes, the variation in the mechanical properties of the 18Ni(C250) maraging steel was analyzed. Specifically, as the cyclic heat treatment temperature increases, the tensile strength of the 18Ni(C250) maraging steel initially increases and then stabilizes, while the elongation and fracture toughness exhibit a monotonic increase.

13.
Mikrochim Acta ; 191(7): 391, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874626

RESUMO

An ultra-high sensitivity pH sensor based on vertical organic electrochemical transistors (vOECT) with extended gate was proposed. The vOECT, which exhibited high transconductance (gm), was for the first time used in the preparation of a pH sensor. The extended gate was modified by electrochemical deposition of polyaniline (PANI) using the cyclic voltammetry (CV) technique. Open circuit potential (OCP) measurements were used to optimize the scan rate, showing a super-Nernstian sensitivity at all scan rates. The pH sensor based on vOECT with extended gate was investigated at different pH levels, and it exhibited an ultra-high sensitivity of 3363.6 µA/pH in the pH range 5-9, which was about 36 times greater than the maximum current sensitivity (91 µA/pH) of other transistor-based pH sensors, to the best of our knowledge. This pH sensor performed excellently in terms of reversibility, long-term stability, and selectivity. To confirm the reliability of the pH sensor, we conducted measurements on real samples using this pH sensor and compared the results with those obtained from a standard pH meter. The ultra-high sensitivity pH sensor based on vOECT with extended gate offers a sensitive and promising alternative in environmental monitoring, food safety, chemistry, clinical diagnostics, and bio-sensing applications.

14.
Zool Res ; 45(4): 781-790, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-38894521

RESUMO

Precise targeting of specific regions within the central nervous system (CNS) is crucial for both scientific research and gene therapy in the context of brain diseases. Adeno-associated virus 13 (AAV13) is known for its restricted diffusion range within the CNS, making it an ideal choice for precise labeling and administration within small brain regions. However, AAV13 mediates relatively low expression of target genes. Here, we introduced specifically engineered modifications to the AAV13 capsid protein to enhance its transduction efficiency. We first constructed AAV13-YF by mutating tyrosine to phenylalanine on the surface of the AAV13 capsid. We then inserted the 7m8 peptide, known to enhance cell transduction, into positions 587/588 and 585/586 of the AAV13 capsid, resulting in two distinct variants named AAV13-587-7m8 and AAV13-585-7m8, respectively. We found that AAV13-YF exhibited superior in vitro infectivity in HEK293T cells compared to AAV13, while AAV13-587-7m8 and AAV13-585-7m8 showed enhanced CNS infection capabilities in C57BL/6 mice, with AAV13-587-7m8 infection retaining a limited spread range. These modified AAV13 variants hold promising potential for applications in gene therapy and neuroscience research.


Assuntos
Dependovirus , Camundongos Endogâmicos C57BL , Dependovirus/genética , Animais , Humanos , Camundongos , Células HEK293 , Transdução Genética , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo
15.
Comput Med Imaging Graph ; 116: 102407, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38880065

RESUMO

The gold standard for diagnosing osteoporosis is bone mineral density (BMD) measurement by dual-energy X-ray absorptiometry (DXA). However, various factors during the imaging process cause domain shifts in DXA images, which lead to incorrect bone segmentation. Research shows that poor bone segmentation is one of the prime reasons of inaccurate BMD measurement, severely affecting the diagnosis and treatment plans for osteoporosis. In this paper, we propose a Multi-feature Joint Discriminative Domain Adaptation (MDDA) framework to improve segmentation performance and the generalization of the network in domain-shifted images. The proposed method learns domain-invariant features between the source and target domains from the perspectives of multi-scale features and edges, and is evaluated on real data from multi-center datasets. Compared to other state-of-the-art methods, the feature prior from the source domain and edge prior enable the proposed MDDA to achieve the optimal domain adaptation performance and generalization. It also demonstrates superior performance in domain adaptation tasks on small amount datasets, even using only 5 or 10 images. In this study, MDDA provides an accurate bone segmentation tool for BMD measurement based on DXA imaging.


Assuntos
Absorciometria de Fóton , Densidade Óssea , Fêmur , Humanos , Fêmur/diagnóstico por imagem , Osteoporose/diagnóstico por imagem , Algoritmos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos
16.
J Environ Manage ; 365: 121475, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38905792

RESUMO

Many urban water bodies grapple with low flow flux and weak hydrodynamics. To address these issues, projects have been implemented to form integrated urban water bodies via interconnecting artificial lake or ponds with rivers, but causing pollution accumulation downstream and eutrophication. Despite it is crucial to assess eutrophication, research on this topic in urban interconnected water bodies is limited, particularly regarding variability and feasible strategies for remediation. This study focused on the Loucun river in Shenzhen, comprising an pond, river and artificial lake, evaluating water quality changes pre-(post-)ecological remediation and establishing a new method for evaluating the water quality index (WQI). The underwater forest project, involving basement improvement, vegetation restoration, and aquatic augmentation, in the artificial lake significantly reduced total nitrogen (by 43.58%), total phosphorus (by 79.17%) and algae density (by 36.90%) compared to pre-remediation, effectively controlling algal bloom. Rainfall, acting as a variable factor, exacerbated downstream nutrient accumulation, increasing total phosphorus by 4.56 times and ammonia nitrogen by 1.30 times compared to the dry season, and leading to algal blooms in the non-restoration pond. The improved WQI method effectively assesses water quality status. The interconnected water body exhibits obvious nutrient accumulation in downstream regions. A combined strategy that reducing nutrient and augmenting flux was verified to alleviate accumulation of nutrients downstream. This study provides valuable insights into pollution management strategies for interconnected pond-river-lake water bodies, offering significant reference for nutrient mitigation in such urban water bodies.


Assuntos
Eutrofização , Fósforo , Fósforo/análise , Qualidade da Água , Nitrogênio/análise , Rios , Lagos , Monitoramento Ambiental/métodos , Recuperação e Remediação Ambiental/métodos
17.
Small ; 20(28): e2308032, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38801010

RESUMO

Low solar energy utilization efficiency and serious charge recombination remain major challenges for photocatalytic systems. Herein, a hollow core-shell Au/g-C3N4@Ag3PO4 photothermal nanoreactor is successfully prepared by a two-step deposition method. Benefit from efficient spectral utilization and fast charge separation induced by the unique hollow core-shell heterostructure, the H2 evolution rate of Au/g-C3N4@Ag3PO4 is 16.9 times that of the pristine g-C3N4, and the degradation efficiency of tetracycline is increased by 88.1%. The enhanced catalytic performance can be attributed to the ordered charge movement on the hollow core-shell structure and a local high-temperature environment, which effectively accelerates the carrier separation and chemical reaction kinetics. This work highlights the important role of the space confinement effect in photothermal catalysis and provides a promising strategy for the development of the next generation of highly efficient photothermal catalysts.

18.
Int J Mol Sci ; 25(10)2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38791283

RESUMO

Fruit color is an intuitive quality of horticultural crops that can be used as an evaluation criterion for fruit ripening and is an important factor affecting consumers' purchase choices. In this study, a genetic population from the cross of green peel 'Qidong' and purple peel '8 guo' revealed that the purple to green color of eggplant peel is dominant and controlled by a pair of alleles. Bulked segregant analysis (BSA), SNP haplotyping, and fine genetic mapping delimited candidate genes to a 350 kb region of eggplant chromosome 10 flanked by markers KA2381 and CA8828. One ANS gene (EGP22363) was predicted to be a candidate gene based on gene annotation and sequence alignment of the 350-kb region. Sequence analysis revealed that a single base mutation of 'T' to 'C' on the exon green peel, which caused hydrophobicity to become hydrophilic serine, led to a change in the three-level spatial structure. Additionally, EGP22363 was more highly expressed in purple peels than in green peels. Collectively, EGP22363 is a strong candidate gene for anthocyanin biosynthesis in purple eggplant peels. These results provide important information for molecular marker-assisted selection in eggplants, and a basis for analyzing the regulatory pathways responsible for anthocyanin biosynthesis in eggplants.


Assuntos
Antocianinas , Mapeamento Cromossômico , Frutas , Solanum melongena , Solanum melongena/genética , Solanum melongena/metabolismo , Antocianinas/biossíntese , Antocianinas/genética , Frutas/genética , Frutas/metabolismo , Pigmentação/genética , Polimorfismo de Nucleotídeo Único , Genes de Plantas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
20.
Nat Commun ; 15(1): 4348, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38777853

RESUMO

The enantioselective synthesis of S-stereogenic sulfinamides has garnered considerable attention due to their structural and physicochemical properties. However, catalytic asymmetric synthesis of sulfinamides still remains daunting challenges, impeding their broad application in drug discovery and development. Here, we present an approach for the synthesis of S-stereogenic sulfinamides through peptide-mimic phosphonium salt-catalyzed asymmetric skeletal reorganization of simple prochiral and/or racemic sulfoximines. This methodology allows for the facile access to a diverse array of substituted sulfinamides with excellent enantioselectivities, accommodating various substituent patterns through desymmetrization or parallel kinetic resolution process. Mechanistic experiments, coupled with density functional theory calculations, clarify a stepwise pathway involving ring-opening and ring-closing processes, with the ring-opening step identified as crucial for achieving stereoselective control. Given the prevalence of S-stereogenic centers in pharmaceuticals, we anticipate that this protocol will enhance the efficient and precise synthesis of relevant chiral molecules and their analogs, thereby contributing to advancements in drug discovery.

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