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1.
Heliyon ; 10(9): e30022, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38726159

RESUMO

Background: Wound healing is a complex biological process that can be impaired in individuals with diabetes. Diabetic wounds are a serious complication of diabetes that require promoting diagnosis and effective treatment. FGF-21, a member of the endocrine FGF factors family, has caught the spotlight in the treatment of diabetes for its beneficial effects on accelerating human glucose uptake and fat catabolism. However, the therapeutic efficacy of FGF-21 in promoting diabetic wounds remains unknown. This study aims to evaluate the therapeutic potential of FGF-21 in promoting diabetic wound healing. Methods: we investigated the effects of FGF-21 on wound healing related-cells under high-glucose conditions using various assays such as CCK8, scratch assay, flow cytometry analysis, endothelial tube-formation assay, and transmission electron microscopy. Furthermore, we used db/db mice to verify the healing-promoting therapeutic effects of FGF-21 on diabetic wounds. We also conducted qRT-PCR, Western blot, and immunofluorescence staining analyses to elucidate the underlying mechanism. Result: Our results indicate that FGF-21 treatment restored hyperglycemic damage on endothelial cell proliferation, migration, and tube-forming ability. It also reduced endothelial cell death rates under high-glucose conditions. TEM analysis showed that FGF-21 treatment effectively restored mitochondrial damage and morphological changes in endothelial cells caused by glucose. Additionally, qRT-PCR and Western blot analysis indicated that FGF-21 treatment restored inflammatory responses caused by hyperglycemic damage. Animal experiments confirmed these findings, suggesting that FGF-21 may be a promising candidate for the treatment of non-healing diabetic wounds due to its effectiveness in stimulating angiogenesis and anti-inflammatory function. Conclusion: Our study provides evidence that FGF-21 is an essential regulator of wound-related cells under high-glucose conditions and has the potential to be a novel therapeutic target for accelerating diabetic wound healing.

2.
Bioengineering (Basel) ; 11(3)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38534519

RESUMO

In this study, we advance our exploration of Apolipoprotein A-I (apoA-I) peptide analogs (APAs) for their application in nanodisc (ND) assembly, focusing on the dynamic conformational characteristics and the potential for drug delivery. We explore APA-ND interactions with an emphasis on curcumin encapsulation, utilizing molecular dynamic simulations and in vitro assessments to evaluate the efficacy of various APA-ND formulations as drug carriers. The methodological approach involved the generation of three unique apoA-I α-11/3 helical mimics, resulting in fifteen distinct APAs. Their structural integrity was rigorously assessed using ColabFold-AF2, with particular attention to pLDDT and pTM scores. Extensive molecular dynamics simulations, covering 1.7 µs across 17 ND systems, were conducted to investigate the influence of APA sequence variations on ND stability and interactions. This study reveals that the composition of APAs, notably the presence of Proline, Serine, and Tryptophan, significantly impacts ND stability and morphology. Oligomeric APAs, in particular, demonstrated superior stability and distinct interaction patterns compared to their monomeric counterparts. Additionally, hydrodynamic diameter measurements over eight weeks indicated sequence-dependent stability, highlighting the potential of specific APA configurations for sustained colloidal stability. In vitro study successfully encapsulated curcumin in [AA]3/DMPC ND formulations, revealing concentration-dependent stability and interaction dynamics. The findings underscore the remarkable capability of APA-NDs to maintain structural integrity and efficient drug encapsulation, positioning them as a promising platform for drug delivery. The study concludes by emphasizing the tunability and versatility of APA-NDs in drug formulation, potentially revolutionizing nanomedicine by enabling customized APA sequences and ND properties for targeted drug delivery.

4.
Front Pharmacol ; 15: 1356876, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469408

RESUMO

Introduction: The root of Reynoutria multiflora (Thunb.) Moldenke (RM) has been used widely in formulations of herbal medicines in China for centuries. Raw R. multiflora (RRM) should be processed before use to reduce toxicity and increase efficacy. However, detailed regulation of the processing endpoint is lacking, and the duration of processing can vary considerably. We conducted in-depth research on stilbene glycosides in RM at different processing times. Previously, we discovered that 219 stilbene glycosides changed markedly in quantity and content. Therefore, we proposed that processing causes changes in various chemical groups. Methods: To better explain the mechanism of RM processing for toxicity reduction and efficacy enhancement, we used a method of tandem mass spectrometry described previously to research gallic acid based and catechin based metabolites. Results: A total of 259 metabolites based on gallic acid and 112 metabolites based on catechins were identified. Among these, the peak areas of 157 gallic acid and 81 catechins gradually decreased, those of another 71 gallic acid and 30 catechins first increased and then decreased, those of 14 gallic acid and 1 catechin gradually increased. However, 17 of the gallic acids showed no significant changes. We speculate that many gallic acid metabolites hydrolyze to produce gallic acid; moreover, the dimers/trimers of catechins, after being cleaved into catechins, epicatechin, gallic acid catechins, and epicatechin monomers, are cleaved into gallic acid and protocatechualdehyde under high temperature and high humidity, subsequently participating in the Maillard reaction and browning reactions. Discussion: We showed that processing led to changes in chemical groups, clarification of the groups of secondary metabolites could provide a basis for research on the pharmacological and toxic mechanisms of RM, as well as the screening of related markers.

5.
Plant Foods Hum Nutr ; 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383946

RESUMO

The evergreen tree species Aquilaria sinensis holds significant economic importance due to its specific medicinal values and increasing market demand. However, the unrestricted illegal exploitation of its wild population poses a threat to its survival. This study aims to contribute to the conservation efforts of A. sinensis by constructing a library database of DNA barcodes, including two chloroplast genes (psbA-trnH and matK) and two nuclear genes (ITS and ITS2). Additionally, the genetic diversity and structure were estimated using inter-simple sequence repeats (ISSR) markers. Four barcodes of 57 collections gained 194 sequences, and 1371 polymorphic bands (98.63%) were observed using DNA ISSR fingerprinting. The Nei's gene diversity (H) of A. sinensis at the species level is 0.2132, while the Shannon information index (I) is 0.3128. The analysis of molecular variance revealed a large significant proportion of total genetic variations and differentiation among populations (Gst = 0.4219), despite a relatively gene flow (Nm = 0.6853) among populations, which were divided into two groups by cluster analysis. There was a close genetic relationship among populations with distances of 0.0845 to 0.5555. This study provides evidence of the efficacy and dependability of establishing a DNA barcode database and using ISSR markers to assess the extent of genetic diversity A. sinensis. Preserving the genetic resources through the conservation of existing populations offers a valuable proposition. The effective utilization of these resources will be further deliberated in subsequent breeding endeavors, with the potential to breed agarwood commercial lines.

6.
J Biomol Struct Dyn ; 42(6): 2809-2824, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37194299

RESUMO

Cyclic peptides (CPs) are a promising class of drugs because of their high biological activity and specificity. However, the design of CP remains challenging due to their conformational flexibility and difficulties in designing stable binding conformation. Herein, we present a high-throughput MD screening (HTMDS) process for the iterative design of stable CP binders with a combinatorial CP library composed of canonical and non-canonical amino acids. As a proof of concept, we apply our methods to design CP inhibitors for the bromodomain (BrD) of ATAD2B. 698,800 CP candidates with a total of 25,570 ns MD simulations were performed to study the protein-ligand binding interactions. The binding free energies (ΔGbind) estimated by MM/PBSA approach for eight lead CP designs were found to be low. CP-1st.43 was the best CP candidate with an estimated ΔGbind of -28.48 kcal/mol when compared to the standard inhibitor C-38 which has been experimentally validated and shown to exhibit ΔGbind of -17.11 kcal/mol. The major contribution of binding sites for BrD of ATAD2B involved the hydrogen-bonding anchor within the Aly-binding pocket, salt bridging, and hydrogen-bonding mediated stabilization of the ZA loop and BC loop, and the complementary Van der Waals attraction. Our methods demonstrate encouraging results by yielding conformationally stable and high-potential CP binders that should have potential applicability in future CP drug development.Communicated by Ramaswamy H. Sarma.


A high-throughput MD screening (HTMDS) process for cyclic peptides (CPs) binders designed with canonical and non-canonical amino acids.698,800 CP candidates with a total of 25,570 ns MD simulations were performed to study the protein-ligand binding interactions and CP design.Some potent CP candidates were obtained with high binding free energies (ΔGbind) estimated by the MM/PBSA approach compared with the standard inhibitor C-38 against the bromodomain (BrD) of ATAD2B.


Assuntos
Simulação de Dinâmica Molecular , Peptídeos Cíclicos , Peptídeos Cíclicos/farmacologia , Sítios de Ligação , Conformação Molecular , Hidrogênio , Simulação de Acoplamento Molecular
7.
Pharmaceutics ; 15(11)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38004601

RESUMO

Biomimetic delivery systems (BDSs), inspired by the intricate designs of biological systems, have emerged as a groundbreaking paradigm in nanomedicine, offering unparalleled advantages in therapeutic delivery. These systems, encompassing platforms such as liposomes, protein-based nanoparticles, extracellular vesicles, and polysaccharides, are lauded for their targeted delivery, minimized side effects, and enhanced therapeutic outcomes. However, the translation of BDSs from research settings to clinical applications is fraught with challenges, including reproducibility concerns, physiological stability, and rigorous efficacy and safety evaluations. Furthermore, the innovative nature of BDSs demands the reevaluation and evolution of existing regulatory and ethical frameworks. This review provides an overview of BDSs and delves into the multifaceted translational challenges and present emerging solutions, underscored by real-world case studies. Emphasizing the potential of BDSs to redefine healthcare, we advocate for sustained interdisciplinary collaboration and research. As our understanding of biological systems deepens, the future of BDSs in clinical translation appears promising, with a focus on personalized medicine and refined patient-specific delivery systems.

8.
Front Plant Sci ; 14: 1270052, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37941675

RESUMO

Generally, chloroplast genomes of angiosperms are always highly conserved but carry a certain number of variation among species. In this study, chloroplast genomes of 13 species from Datureae tribe that are of importance both in ornamental gardening and medicinal usage were studied. In addition, seven chloroplast genomes from Datureae together with two from Solanaceae species retrieved from the National Center for Biotechnology Information (NCBI) were integrated into this study. The chloroplast genomes ranged in size from 154,686 to 155,979 and from 155,497 to 155,919 bp for species of Datura and Brugmansia, respectively. As to Datura and Brugmansia, a total of 128 and 132 genes were identified, in which 83 and 87 protein coding genes were identified, respectively; Furthermore, 37 tRNA genes and 8 rRNA genes were both identified in Datura and Brugmansia. Repeats analysis indicated that the number and type varied among species for Simple sequence repeat (SSR), long repeats, and tandem repeats ranged in number from 53 to 59, 98 to 99, and 22 to 30, respectively. Phylogenetic analysis based on the plastid genomes supported the monophyletic relationship among Datura and Brugmansia and Trompettia, and a refined phylogenic relationships among each individual was resolved. In addition, a species-specific marker was designed based on variation spot that resulted from a comparative analysis of chloroplast genomes and verified as effective maker for identification of D. stramonium and D. stramonium var. inermis. Interestingly, we found that 31 genes were likely to be under positive selection, including genes encoding ATP protein subunits, photosystem protein subunit, ribosome protein subunits, NAD(P)H dehydrogenase complex subunits, and clpP, petB, rbcL, rpoCl, ycf4, and cemA genes. These genes may function as key roles in the adaption to diverse environment during evolution. The diversification of Datureae members was dated back to the late Oligocene periods. These chloroplast genomes are useful genetic resources for taxonomy, phylogeny, and evolution for Datureae.

9.
BMC Genomics ; 24(1): 692, 2023 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-37980503

RESUMO

BACKGROUND: Artemisia annua is the major source for artemisinin production. The artemisinin content in A. annua is affected by different types of light especially the UV light. UVR8, a member of RCC1 gene family was found to be the UV-B receptor in plants. The gene structures, evolutionary history and expression profile of UVR8 or RCC1 genes remain undiscovered in A. annua. RESULTS: Twenty-two RCC1 genes (AaRCC1) were identified in each haplotype genome of two diploid strains of A. annua, LQ-9 and HAN1. Varied gene structures and sequences among paralogs were observed. The divergence of most RCC1 genes occurred at 46.7 - 51 MYA which overlapped with species divergence of core Asteraceae during the Eocene, while no recent novel RCC1 members were found in A. annua genome. The number of RCC1 genes remained stable among eudicots and RCC1 genes underwent purifying selection. The expression profile of AaRCC1 is analogous to that of Arabidopsis thaliana (AtRCC1) when responding to environmental stress. CONCLUSIONS: This study provided a comprehensive characterization of the AaRCC1 gene family and suggested that RCC1 genes were conserved in gene number, structures, constitution of amino acids and expression profiles among eudicots.


Assuntos
Arabidopsis , Artemisia annua , Artemisininas , Artemisia annua/genética , Artemisia annua/metabolismo , Artemisininas/metabolismo , Genes de Plantas , Arabidopsis/genética , Arabidopsis/metabolismo , Cromossomos/metabolismo
10.
BMC Public Health ; 23(1): 2277, 2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37978471

RESUMO

BACKGROUND: The relationship between the Coronavirus Disease 2019 (COVID-19) pandemic, which is a traumatic event for adolescents, and procrastination is not clear. Mental health may play an important role in this relationship; however, the underlying mechanisms remain unknown. This study aimed to construct chain mediation models to examine whether anxiety and depression symptoms mediate the effects of the COVID-19 pandemic on procrastination in adolescents. METHODS: A convenience sample of 12 middle and high schools in Harbin, China, with four follow-up online surveys was conducted during the COVID-19 pandemic. A total of 4,156 Chinese adolescents were enrolled in this study, of whom ages 11-18 (Mean = 13.55; SD = 1.18), 50.75% were male, and 93.24% were middle school students. Descriptive demographic analysis and Pearson's correlation analysis of the effects of the COVID-19 pandemic (T1), anxiety(T2), depression (T3), and procrastination (T4) were performed in SPSS 22.0. Chain mediation analysis performed with Mplus 8.3. RESULTS: The effects of the COVID-19 pandemic, anxiety symptoms, depression symptoms, and procrastination were positively correlated (P < 0.01). The effects of the COVID-19 pandemic have a direct link on adolescent procrastination (effect = 0.156; SE = 0.031; 95%CI: 0.092, 0.214), and have three indirect paths on procrastination: the independent mediating role of anxiety symptoms was 29.01% (effect = 0.047; SE = 0.012; 95%CI: 0.024, 0.072), the independent mediating role of depression symptoms was 29.01% (effect = 0.047; SE = 0.010; 95%CI: 0.030, 0.068), as well as the completely chain mediating role of anxiety and depression symptoms was 15.43% (effect = 0.025; SE = 0.005; 95%CI: 0.017, 0.036). CONCLUSIONS: Our results suggest that anxiety and depressive symptoms are part of a causal chain between the effects of the COVID-19 pandemic and procrastination among Chinese adolescents. To effectively reduce their procrastination, attention should be paid to the emotional distress caused to adolescents by major events such as the COVID-19 epidemic. All data were taken from self-reported measures and one city in China, which may bias the results and limit their generalizability.


Assuntos
COVID-19 , Procrastinação , Adolescente , Masculino , Humanos , Feminino , Pandemias , Estudos Longitudinais , Depressão/epidemiologia , COVID-19/epidemiologia , Ansiedade/epidemiologia , China/epidemiologia
11.
J Mol Biol ; 435(22): 168293, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37775038

RESUMO

Arl8b, a specific Arf-like family GTPase present on lysosome, and plays critical roles in many lysosome-related cellular processes such as autophagy. The active Arl8b can be specifically recognized by the RUN domains of two Arl8b-effectors PLEKHM1 and SKIP, thereby regulating the autophagosome/lysosome membrane fusion and the intracellular lysosome positioning, respectively. However, the mechanistic bases underlying the interactions of Arl8b with the RUN domains of PLEKHM1 and SKIP remain elusive. Here, we report the two high-resolution crystal structures of the active Arl8b in complex with the RUN domains of PLEKHM1 and SKIP. In addition to elucidating the detailed molecular mechanism governing the specific interactions of the active Arl8b with the RUN domains of PLEKHM1 and SKIP, the determined complex structures also reveal a general binding mode shared by the PLEKHM1 and SKIP RUN domains for interacting with the active Arl8b. Furthermore, we uncovered a competitive relationship between the RUN domains of PLEKHM1 and SKIP in binding to the active Arl8b as well as a unique small GTPase-binding mode adopted by the PLEKHM1 and SKIP RUN domains, thereby enriching the repertoire of the RUN domain/small GTPase interaction modes. In all, our findings provide new mechanistic insights into the interactions of the active Arl8b with PLEKHM1 and SKIP, and are valuable for further understanding the working modes of these proteins in relevant cellular processes.


Assuntos
Fatores de Ribosilação do ADP , Proteínas Adaptadoras de Transdução de Sinal , Proteínas Relacionadas à Autofagia , Coativadores de Receptor Nuclear , Domínios e Motivos de Interação entre Proteínas , Proteínas Adaptadoras de Transdução de Sinal/química , Lisossomos/metabolismo , Fusão de Membrana , Fatores de Ribosilação do ADP/química , Proteínas Relacionadas à Autofagia/química , Coativadores de Receptor Nuclear/química , Cristalografia por Raios X , Humanos
12.
Nat Commun ; 14(1): 5813, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37726300

RESUMO

Establishing a general model of heterogeneous ice nucleation has long been challenging because of the surface water structures found on different substrates. Identifying common water clusters, regardless of the underlying substrate, is one of the key steps toward solving this problem. Here, we demonstrate the presence of a common water cluster found on both hydrophilic Pt(111) and hydrophobic Cu(111) surfaces using scanning tunneling microscopy and non-contact atomic force microscopy. Water molecules self-assemble into a structure with a central flat-lying hexagon and three fused pentagonal rings, forming a cluster consisting of 15 individual water molecules. This cluster serves as a critical nucleus during ice nucleation on both surfaces: ice growth beyond this cluster bifurcates to form two-dimensional (three-dimensional) layers on hydrophilic (hydrophobic) surfaces. Our results reveal the inherent similarity and distinction at the initial stage of ice growth on hydrophilic and hydrophobic close-packed metal surfaces; thus, these observations provide initial evidence toward a general model for water-substrate interaction.

13.
Ann Clin Transl Neurol ; 10(10): 1749-1767, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37614011

RESUMO

OBJECTIVE: While existing literature has provided insights into involvement of circEPHB4, SOX2 in glioma, their precise molecular mechanisms and synergistic implications in glioma pathogenesis still dim. This study aims to investigate significance and underlying mechanism of m6A-modified circEPHB4 in regulating SOX2/PHLDB2 axis in gliomas. METHODS: The mRNA and protein expression were tested by qRT-PCR and Western blot, respectively. ChIP assay was performed to detect SOX2 enrichment on the PHLDB2 promoter. Cell sphere-forming assay to detect self-renewal ability, flow cytometry to determine positivity of CD133 expressions, Malignant behavior of glioma cells were detected by CCK-8, plate colony formation, scratch, and transwell assays. Glioma xenograft models were constructed to investigate effects of CircEPHB4 in tumor development in vivo. RESULTS: Methyltransferase MELLT3 upregulated m6A modification of CircEPHB4, and YTHDC1 promoted cytoplasmic localization of m6A-modified CircEPHB4. Overexpression of wild-type CircEPHB4 enhanced glioma cells' stemness, metastasis, and proliferation. Cytoplasmic CircEPHB4 increased SOX2 mRNA stability by binding to IGF2BP2, and the effects observed by SOX2 knockdown were reversed by CircEPHB4 in glioma cells. SOX2 promoted transcriptional expression of PHLDB2 by enriching the PHLDB2 promoter region. SOX2 reversed the inhibition of PHLDB2 knockdown on stemness of glioma, cell proliferation, and metastasis. In vivo experiments also revealed that CircEPHB4 upregulated PHLDB2 expression by stabilizing SOX2 mRNA, which promoted in vivo tumor growth and accelerated stemness of glioma cells and metastasis. CONCLUSION: This study reveals functional interaction and molecular mechanisms of m6A-modified circEPHB4 in regulating SOX2/PHLDB2 axis, highlighting their importance in glioma pathogenesis and potential as therapeutic targets.


Assuntos
Glioma , Humanos , Linhagem Celular Tumoral , Glioma/genética , Glioma/patologia , Proliferação de Células , RNA Mensageiro , Proteínas de Ligação a RNA/genética
14.
bioRxiv ; 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37503076

RESUMO

High energy-demanding tissues, such as skeletal muscle, require mitochondrial proteostasis to function properly. Two quality-control mechanisms, the ubiquitin proteasome system (UPS) and the release of mitochondria-derived vesicles, safeguard mitochondrial proteostasis. However, whether these processes interact is unknown. Here we show that the E3 ligase CRL5 Ozz , a member of the UPS, and its substrate Alix control the mitochondrial concentration of Slc25A4, a solute carrier that is essential for ATP production. The mitochondria in Ozz -/- or Alix -/- skeletal muscle share overt morphologic alterations (they are supernumerary, swollen, and dysmorphic) and have abnormal metabolomic profiles. We found that CRL5 Ozz ubiquitinates Slc25A4 and promotes its proteasomal degradation, while Alix facilitates SLC25A4 loading into exosomes destined for lysosomal destruction. The loss of Ozz or Alix offsets steady-state levels of Slc25A4, which disturbs mitochondrial metabolism and alters muscle fiber composition. These findings reveal hitherto unknown regulatory functions of Ozz and Alix in mitochondrial proteostasis.

15.
Front Psychol ; 14: 1168463, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37425149

RESUMO

Background: Despite the growing attention given to adolescent behavior problems, little is known about the trajectories and factors that have influenced adolescent procrastination during the COVID-19 pandemic. This study monitors changes in procrastination behavior among Chinese adolescents during the pandemic and identifies vulnerable groups. Methods: A four-wave study using a representative sample of 11-to 18-year-olds in China was conducted, with baseline data collected in June 2020 (n = 4,156; 49% girls) and follow-ups in December 2020 (n = 3,392; 50% girls), August 2021 (n = 2,380; 48% girls), and October 2021 (n = 1,485; 49% girls). Procrastination behavior was assessed using the General Procrastination Scale. Latent growth curve models, latent growth mixture modes, and multivariate logistic regression models were used to describe the trajectory of procrastination and identify predictors of deterioration. Results: The proportion and overall trends of adolescent procrastination increased with the pandemic. Higher parental over-protection was a contributing factor to the higher baseline levels leading to the faster growth of adolescent procrastination. The model identified three distinct trajectories of low-increasing [including 2,057 participants (49.5%)], moderate-stable [including 1,879 participants (45.2%)], and high-decreasing procrastination [including 220 participants (5.3%)]. More daily leisure screen-time, lower frequency of exercise weekly, and dissatisfaction with distance learning were the top three risk factors for moderate-stable and high-decreasing procrastination compared to low-increasing procrastination. Adolescents with mothers with a higher level of education were more liable to be high-decreasing procrastination than moderate-stable procrastination. Conclusion: The proportion and overall trends of adolescent procrastination increased with the pandemic. The categories of procrastination among adolescents during that time period were probed. Also, the study further clarified the risk factors for severe and moderate procrastination relative to no procrastination. Thus, effective procrastination prevention and intervention strategies need to be implemented to support adolescents, particularly those at risk.

16.
Small ; 19(45): e2301959, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37329191

RESUMO

Strain is an effective strategy to modulate the electrical, optical, and optoelectronic properties of 2D materials. Conventional circular blisters could generate a biaxial stretching of 2D membranes with notable strain gradients along the hoop direction. However, such a deformation mode cannot be utilized to investigate mechanical responses of in-plane anisotropic 2D materials, for example, black phosphorus (BP), due to its crystallographic orientation dependence. Here, a novel rectangular-shaped bulge device is developed to uniaxially stretch the membrane, and further provide a promising platform to detect orientation-dependent mechanical and optical properties of anisotropic 2D materials. Impressively, the derived anisotropic ratio of Young's modulus of BP flakes is much higher than the values obtained via the nanoindentation method. The extra-high strain-dependent phononic anisotropy in Raman modes along different crystalline orientations is also observed. The designed rectangular budge device expands the uniaxial deformation methods available, allowing to explore the mechanical, and strain-dependent physical properties of other anisotropic 2D materials more broadly.

17.
Acta Pharm Sin B ; 13(5): 2234-2249, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37250171

RESUMO

The many-banded krait, Bungarus multicinctus, has been recorded as the animal resource of JinQianBaiHuaShe in the Chinese Pharmacopoeia. Characterization of its venoms classified chief phyla of modern animal neurotoxins. However, the evolutionary origin and diversification of its neurotoxins as well as biosynthesis of its active compounds remain largely unknown due to the lack of its high-quality genome. Here, we present the 1.58 Gbp genome of B. multicinctus assembled into 18 chromosomes with contig/scaffold N50 of 7.53 Mbp/149.8 Mbp. Major bungarotoxin-coding genes were clustered within genome by family and found to be associated with ancient local duplications. The truncation of glycosylphosphatidylinositol anchor in the 3'-terminal of a LY6E paralog released modern three-finger toxins (3FTxs) from membrane tethering before the Colubroidea divergence. Subsequent expansion and mutations diversified and recruited these 3FTxs. After the cobra/krait divergence, the modern unit-B of ß-bungarotoxin emerged with an extra cysteine residue. A subsequent point substitution in unit-A enabled the ß-bungarotoxin covalent linkage. The B. multicinctus gene expression, chromatin topological organization, and histone modification characteristics were featured by transcriptome, proteome, chromatin conformation capture sequencing, and ChIP-seq. The results highlighted that venom production was under a sophisticated regulation. Our findings provide new insights into snake neurotoxin research, meanwhile will facilitate antivenom development, toxin-driven drug discovery and the quality control of JinQianBaiHuaShe.

18.
Phytomedicine ; 116: 154882, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37210961

RESUMO

BACKGROUND: Artemisia annua, a well-known traditional Chinese medicine, is the main source for production of artemisinin, an anti-malaria drug. A. annua is distributed globally, with great diversity of morphological characteristics and artemisinin contents. Diverse traits among A. annua populations impeded the stable production of artemisinin, which needs an efficient tool to identify strains and assess population genetic homogeneity. PURPOSE: In this study, ribosomal DNA (rDNA), were characterized for A. annua for strains identification and population genetic homogeneity assessment. METHODS: The ribosomal RNA (rRNA) genes were identified using cmscan and assembled using rDNA unit of LQ-9 as a reference. rDNA among Asteraceae species were compared performing with 45S rDNA. The rDNA copy number was calculated based on sequencing depth. The polymorphisms of rDNA sequences were identified with bam-readcount, and confirmed by Sanger sequencing and restriction enzyme experiment. The ITS2 amplicon sequencing was used to verify the stability of ITS2 haplotype analysis. RESULTS: Different from other Asteraceae species, 45S and 5S linked-type rDNA was only found in Artemisia genus. Rich polymorphisms of copy number and sequence of rDNA were identified in A. annua population. The haplotype composition of internal transcribed spacer 2 (ITS2) region which had moderate sequence polymorphism and relative short size was significantly different among A. annua strains. A population discrimination method was developed based on ITS2 haplotype analysis with high-throughput sequencing. CONCLUSION: This study provides comprehensive characteristics of rDNA and suggests that ITS2 haplotype analysis is ideal tool for A. annua strain identification and population genetic homogeneity assessment.


Assuntos
Artemisia annua , Artemisininas , Asteraceae , Artemisia annua/genética , DNA Ribossômico/genética , Medicina Tradicional Chinesa
19.
Nat Commun ; 14(1): 2223, 2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37076513

RESUMO

The chiral charge density wave is a many-body collective phenomenon in condensed matter that may play a role in unconventional superconductivity and topological physics. Two-dimensional chiral charge density waves provide the building blocks for the fabrication of various stacking structures and chiral homostructures, in which physical properties such as chiral currents and the anomalous Hall effect may emerge. Here, we demonstrate the phase manipulation of two-dimensional chiral charge density waves and the design of in-plane chiral homostructures in 1T-TaS2. We use chiral Raman spectroscopy to directly monitor the chirality switching of the charge density wave-revealing a temperature-mediated reversible chirality switching. We find that interlayer stacking favours homochirality configurations, which is confirmed by first-principles calculations. By exploiting the interlayer chirality-locking effect, we realise in-plane chiral homostructures in 1T-TaS2. Our results provide a versatile way to manipulate chiral collective phases by interlayer coupling in layered van der Waals semiconductors.

20.
Nat Commun ; 14(1): 1882, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-37019911

RESUMO

The outcomes of FLT3-ITD acute myeloid leukaemia (AML) have been improved since the approval of FLT3 inhibitors (FLT3i). However, approximately 30-50% of patients exhibit primary resistance (PR) to FLT3i with poorly defined mechanisms, posing a pressing clinical unmet need. Here, we identify C/EBPα activation as a top PR feature by analyzing data from primary AML patient samples in Vizome. C/EBPα activation limit FLT3i efficacy, while its inactivation synergistically enhances FLT3i action in cellular and female animal models. We then perform an in silico screen and identify that guanfacine, an antihypertensive medication, mimics C/EBPα inactivation. Furthermore, guanfacine exerts a synergistic effect with FLT3i in vitro and in vivo. Finally, we ascertain the role of C/EBPα activation in PR in an independent cohort of FLT3-ITD patients. These findings highlight C/EBPα activation as a targetable PR mechanism and support clinical studies aimed at testing the combination of guanfacine with FLT3i in overcoming PR and enhancing the efficacy of FLT3i therapy.


Assuntos
Guanfacina , Leucemia Mieloide Aguda , Animais , Feminino , Tirosina Quinase 3 Semelhante a fms , Guanfacina/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Mutação , Inibidores de Proteínas Quinases/farmacologia , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo
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