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1.
Proc Natl Acad Sci U S A ; 121(15): e2315730121, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38557188

RESUMO

Microdroplets are a class of soft matter that has been extensively employed for chemical, biochemical, and industrial applications. However, fabricating microdroplets with largely controllable contact-area shape and apparent contact angle, a key prerequisite for their applications, is still a challenge. Here, by engineering a type of surface with homocentric closed-loop microwalls/microchannels, we can achieve facile size, shape, and contact-angle tunability of microdroplets on the textured surfaces by design. More importantly, this class of surface topologies (with universal genus value = 1) allows us to reveal that the conventional Gibbs equation (widely used for assessing the edge effect on the apparent contact angle of macrodroplets) seems no longer applicable for water microdroplets or nanodroplets (evidenced by independent molecular dynamics simulations). Notably, for the flat surface with the intrinsic contact angle ~0°, we find that the critical contact angle on the microtextured counterparts (at edge angle 90°) can be as large as >130°, rather than 90° according to the Gibbs equation. Experiments show that the breakdown of the Gibbs equation occurs for microdroplets of different types of liquids including alcohol and hydrocarbon oils. Overall, the microtextured surface design and topological wetting states not only offer opportunities for diverse applications of microdroplets such as controllable chemical reactions and low-cost circuit fabrications but also provide testbeds for advancing the fundamental surface science of wetting beyond the Gibbs equation.

2.
Nat Chem Biol ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039255

RESUMO

The phosphoinositide 3-kinase (PI3K)-Akt axis is one of the most frequently activated pathways and is demonstrated as a therapeutic target in Kirsten rat sarcoma viral oncogene homolog (KRAS)-mutated colorectal cancer (CRC). Targeting the PI3K-Akt pathway has been a challenging undertaking through the decades. Here we unveiled an essential role of E3 ligase SMAD ubiquitylation regulatory factor 1 (Smurf1)-mediated phosphoinositide-dependent protein kinase 1 (PDK1) neddylation in PI3K-Akt signaling and tumorigenesis. Upon growth factor stimulation, Smurf1 immediately triggers PDK1 neddylation and the poly-neural precursor cell expressed developmentally downregulated protein 8 (poly-Nedd8) chains recruit methyltransferase SET domain bifurcated histone lysine methyltransferase 1 (SETDB1). The cytoplasmic complex of PDK1 assembled with Smurf1 and SETDB1 (cCOMPASS) consisting of PDK1, Smurf1 and SETDB1 directs Akt membrane attachment and T308 phosphorylation. Smurf1 deficiency dramatically reduces CRC tumorigenesis in a genetic mouse model. Furthermore, we developed a highly selective Smurf1 degrader, Smurf1-antagonizing repressor of tumor 1, which exhibits efficient PDK1-Akt blockade and potent tumor suppression alone or combined with PDK1 inhibitor in KRAS-mutated CRC. The findings presented here unveil previously unrecognized roles of PDK1 neddylation and offer a potential strategy for targeting the PI3K-Akt pathway and KRAS mutant cancer therapy.

3.
Acc Chem Res ; 57(9): 1458-1466, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38654437

RESUMO

ConspectusRecent years have witnessed the development of cluster materials as they are atomically precise molecules with uniform size and solution-processability, which are unattainable with traditional nanoparticles or framework materials. The motivation for studying Al(III) chemistry is not only to understand the aggregation process of aluminum in the environment but also to develop novel low-cost materials given its natural abundance. However, the Al-related clusters are underdeveloped compared to the coinage metals, lanthanides, and transition metals. The challenge in isolating crystalline compounds is the lack of an effective method to realize the controllable hydrolysis of Al(III) ions. Compared with the traditional hydrolysis of inorganic Al(III) salts in highly alkaline solutions and hydrolysis of aluminum trialkyl compounds conducted carefully in an inert operating environment, we herein developed an effective way to control the hydrolysis of aluminum isopropanol through an alcoxalation reaction. By solvothermal/low melting point solid melting synthesis and using "ligand aggregation, solvent regulation, and supracluster assembly" strategies, our laboratory has established an organic-inorganic hybrid system of aluminum oxo clusters (AlOCs). The employment of organic ligands promotes the aggregation and slows the hydrolysis of Al(III) ions, which in turn improves the crystallization process. The regulation of the structure types can be achieved through the selection of ligands and the supporting solvents. Compared with the traditional condensed polyoxoaluminates, we successfully isolated a broad range of porous AlOCs, including aluminum molecular rings and Archimedes aluminum oxo cages. By studying ring expansion, structural transformation, and intermolecular supramolecular assembly, we demonstrate unique and unprecedented structural controllability and assembly behavior in cluster science. The advancement of this universal synthetic method is to realize materials customization through modularly oriented supracluster assembly. In this Account, we will provide a clear-cut definition and terminology of "ligand aggregation, solvent regulation, and supracluster assembly". Then we will discuss the discovery in this area by using a strategy, such as aluminum molecular ring, ring size expansion, ring supracluster assembly, etc. Furthermore, given the internal and external pore structures, as well as the solubility and modifiability of the AlOCs, we will demonstrate their potential applications in both the solid and liquid phases, such as iodine capture, the optical limiting responses, and dopant in polymer dielectrics. The strategy herein can be applied to extensive cluster science and promote the research of main group element chemistry. The new synthetic method, fascinating clusters, and unprecedented assembly behaviors we have discovered will advance Al(III) chemistry and will also lay the foundation for functional applications.

4.
FASEB J ; 38(8): e23613, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38661048

RESUMO

The unpredictable survival rate of autologous fat grafting (AFG) seriously affects its clinical application. Improving the survival rate of AFG has become an unresolved issue in plastic surgery. Peroxisome proliferator-activated receptor-γ (PPAR-γ) regulates the adipogenic differentiation of adipocytes, but the functional mechanism in AFG remains unclear. In this study, we established an animal model of AFG and demonstrated the superior therapeutic effect of PPAR-γ regulation in the process of AFG. From day 3 after fat grafting, the PPAR-γ agonist rosiglitazone group consistently showed better adipose integrity, fewer oil cysts, and fibrosis. Massive macrophage infiltration was observed after 7 days. At the same time, M2 macrophages begin to appear. At day 14, M2 macrophages gradually became the dominant cell population, which suppressed inflammation and promoted revascularization and fat regeneration. In addition, transcriptome sequencing showed that the differentially expressed genes in the Rosiglitazone group were associated with the pathways of adipose regeneration, differentiation, and angiogenesis; these results provide new ideas for clinical treatment.


Assuntos
Tecido Adiposo , Macrófagos , PPAR gama , Rosiglitazona , Transplante Autólogo , Animais , PPAR gama/metabolismo , PPAR gama/genética , Macrófagos/metabolismo , Tecido Adiposo/metabolismo , Tecido Adiposo/citologia , Rosiglitazona/farmacologia , Masculino , Diferenciação Celular , Adipogenia , Adipócitos/metabolismo , Camundongos , Ratos
5.
Nano Lett ; 24(9): 2712-2718, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38407061

RESUMO

Colloidal semiconductor nanocrystals are promising candidates for quantum light sources, yet their application has been impeded by photoluminescence instability due to blinking and spectral diffusion. This study introduces a new category of cube-shaped CdSe/CdS core/shell nanocrystals with exceptionally stable photoluminescence characteristics. Under continuous excitation, the emissive quantum state remained consistent without alterations of the charge state for 4000 s, and the average photon energy variation stayed within the bounds of spectral resolution throughout this extended duration. Systematic examination of single-nanocrystal photoluminescence, upon variation of the core and shell dimensions, revealed that a thicker CdS shell and increased core edge length significantly curtail spectral diffusion, considering that the nanocrystals possess well-controlled CdSe-CdS and facet-ligand interfaces. This study advances the optimization of colloidal semiconductor nanocrystals as high-performance quantum light sources.

6.
J Cell Mol Med ; 28(10): e18381, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38780509

RESUMO

Peritoneal fibrosis is a common pathological response to long-term peritoneal dialysis (PD) and a major cause for PD discontinuation. Understanding the cellular and molecular mechanisms underlying the induction and progression of peritoneal fibrosis is of great interest. In our study, in vitro study revealed that signal transducer and activator of transcription 3 (STAT3) is a key factor in fibroblast activation and extracellular matrix (ECM) synthesis. Furthermore, STAT3 induced by IL-6 trans-signalling pathway mediate the fibroblasts of the peritoneal stroma contributed to peritoneal fibrosis. Inhibition of STAT3 exerts an antifibrotic effect by attenuating fibroblast activation and ECM production with an in vitro co-culture model. Moreover, STAT3 plays an important role in the peritoneal fibrosis in an animal model of peritoneal fibrosis developed in mice. Blocking STAT3 can reduce the peritoneal morphological changes induced by chlorhexidine gluconate. In conclusion, our findings suggested STAT3 signalling played an important role in peritoneal fibrosis. Therefore, blocking STAT3 might become a potential treatment strategy in peritoneal fibrosis.


Assuntos
Ácidos Aminossalicílicos , Fibroblastos , Fibrose Peritoneal , Fenótipo , Fator de Transcrição STAT3 , Transdução de Sinais , Fibrose Peritoneal/metabolismo , Fibrose Peritoneal/patologia , Fibrose Peritoneal/etiologia , Fibrose Peritoneal/genética , Fator de Transcrição STAT3/metabolismo , Animais , Fibroblastos/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , Camundongos , Ácidos Aminossalicílicos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Modelos Animais de Doenças , Peritônio/patologia , Peritônio/metabolismo , Interleucina-6/metabolismo , Matriz Extracelular/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Humanos , Clorexidina/análogos & derivados , Clorexidina/farmacologia , Diálise Peritoneal/efeitos adversos , Benzenossulfonatos
7.
J Cell Mol Med ; 28(5): e18065, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38116696

RESUMO

Colorectal cancer (CRC) is the most prevalent malignancy of the digestive system. Glucose metabolism plays a crucial role in CRC development. However, the heterogeneity of glucose metabolic patterns in CRC is not well characterized. Here, we classified CRC into specific glucose metabolic subtypes and identified the key regulators. 2228 carbohydrate metabolism-related genes were screened out from the GeneCards database, 202 of them were identified as prognosis genes in the TCGA database. Based on the expression patterns of the 202 genes, three metabolic subtypes were obtained by the non-negative matrix factorization clustering method. The C1 subtype had the worst survival outcome and was characterized with higher immune cell infiltration and more activation in extracellular matrix pathways than the other two subtypes. The C2 subtype was the most prevalent in CRC and was characterized by low immune cell infiltration. The C3 subtype had the smallest number of individuals and had a better prognosis, with higher levels of NRF2 and TP53 pathway expression. Secreted frizzled-related protein 2 (SFRP2) and thrombospondin-2 (THBS2) were confirmed as biomarkers for the C1 subtype. Their expression levels were elevated in high glucose condition, while their knockdown inhibited migration and invasion of HCT 116 cells. The analysis of therapeutic potential found that the C1 subtype was more sensitive to immune and PI3K-Akt pathway inhibitors than the other subtypes. To sum up, this study revealed a novel glucose-related CRC subtype, characterized by SFRP2 and THBS2, with poor prognosis but possible therapeutic benefits from immune and targeted therapies.


Assuntos
Neoplasias Colorretais , Regulação Neoplásica da Expressão Gênica , Glucose , Transcriptoma , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Glucose/metabolismo , Transcriptoma/genética , Prognóstico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Trombospondinas/genética , Trombospondinas/metabolismo , Movimento Celular/genética , Perfilação da Expressão Gênica , Células HCT116 , Transdução de Sinais , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo
8.
J Am Chem Soc ; 146(28): 19547-19554, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38976802

RESUMO

We simulated hot-electron relaxation in black phosphorus using the nonadiabatic molecular dynamics (NA-MD) approach with a non-Condon effect in momentum space beyond the harmonic approximation. By comparing simulations at the Γ point in a large supercell with those using a few k-points in a smaller supercell─while maintaining the same number of electronic states within the same energy range, we demonstrate that both setups yield remarkably consistent energy relaxation times, regardless of the initial state energy. This consistency arises from the complementary effects of supercell size in real space and the number of k-points in the reciprocal space. This finding confirms that simulations at a single k-point in large size supercells are an effective approximation for NA-MD with a non-Condon effect. This approach offers significant advantages for complex photophysics, such as intervalley scattering and indirect bandgap charge recombination, and is particularly suitable for large systems without the need for a harmonic approximation.

9.
J Am Chem Soc ; 146(30): 21052-21060, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39013148

RESUMO

Chlorine oxides play crucial roles in ozone depletion, and the final oxidation steps of chlorine oxide potentially result in the formation of chloric acid (HClO3) or perchloric acid (HClO4). Herein, the solvation and reactive uptake of three stable isomers of chlorine trioxide (Cl2O3), namely, ClOCl(O)O, ClClO3, and ClOOOCl, at the air-water interface were investigated using classical and hybrid quantum mechanics/molecular mechanics (QM/MM) molecular dynamics (MD) coupled with advanced free energy methods. Two distinct mechanisms were revealed for the hydrolysis of ClOCl(O)O and ClClO3: molecular and ionic mechanisms. A comparison of the computed free-energy profiles for the gaseous and air-water interfacial systems indicated that the air-water interface could markedly lower the free-energy barrier for ClO3- or HClO3 formation while stabilizing the product state. In particular, the hydrolysis of ClClO3 at the air-water interface was barrierless. In contrast, our calculations showed that the hydrolysis of ClOOOCl was very slow, indicating that ClOOOCl was inert to water at the air-water interface. This study provides theoretical evidence for the hypothesis that HClO3 is a sink for chlorine oxides and for the widespread distributions of HClO3 recently observed in the Arctic region.

10.
J Am Chem Soc ; 146(23): 16314-16323, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38812460

RESUMO

Two-dimensional (2D) metal halide perovskites, such as BA2SnI4 (BA═CH3(CH2)3NH3), exhibit an enhanced charge carrier lifetime in experiments under strain. Experiments suggest that significant compression of the BA molecule, rather than of the inorganic lattice, contributes to this enhancement. To elucidate the underlying physical mechanism, we apply a moderate compressive strain to the entire system and subsequently introduce significant compression to the BA molecules. We then perform ab initio nonadiabatic molecular dynamics simulations of nonradiative electron-hole recombination. We observe that the overall lattice compression reduces atomic motions and decreases nonadiabatic coupling, thereby delaying electron-hole recombination. Additionally, compression of the BA molecules enhances hydrogen bonding between the BA molecules and iodine atoms, which lengthens the Sn-I bonds, distorts the [SnI6]4- octahedra, and suppresses atomic motions further, thus reducing nonadiabatic coupling. Also, the elongated Sn-I bonds and weakened antibonding interactions increase the band gap. Altogether, the compression delays the nonradiative electron-hole recombination by more than a factor of 3. Our simulations provide new and valuable physical insights into how compressive strain, accommodated primarily by the organic ligands, positively influences the optoelectronic properties of 2D layered halide perovskites, offering a promising pathway for further performance improvements.

11.
J Am Chem Soc ; 146(11): 7524-7532, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38451059

RESUMO

Chiral aluminum oxo clusters (cAlOCs) are distinguished from other classes of materials on account of their abundance in the earth's crust and their potential for sustainable development. However, the practical synthesis of cAlOCs is rarely known. Herein, we adopt a synergistic coordination strategy by using chiral amino acid ligands as bridges and auxiliary pyridine-2,6-dicarboxylic acid as chelating ligands and successfully isolate an extensive family of cAlOCs. They integrate molecular chirality, absolute helicity, and intrinsic hydrogen-bonded chiral topology. Moreover, they have the structural characteristics of one-dimensional channels and replaceable counteranions, which make them well combined with fluorescent dyes for circularly polarized luminescence (CPL). The absolute luminescence dissymmetry factor (glum) of up to the 10-3 order is comparable to several noble metals, revealing the enormous potential of cAlOCs in low-cost chiral materials. We hope this work will inspire new discoveries in the field of chirality and provide new opportunities for constructing low-cost chiral materials.

12.
J Am Chem Soc ; 146(31): 21742-21751, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39074151

RESUMO

The activation of halogens (X = Cl, Br, I) by N2O5 is linked to NOx sources, ozone concentrations, NO3 reactivity, and the chemistry of halide-containing aerosol particles. However, a detailed chemical mechanism is still lacking. Herein, we explored the chemistry of the N2O5···X- systems at the air-water interface. Two different reaction pathways were identified for the reaction of N2O5 with X- at the air-water interface: the formation of XNO2 or XONO, along with NO3-. In the case of the Cl- system, the ClNO2 generation pathway is more favorable, while for the Br- and I- systems, the formation of BrONO and IONO is barrierless, making them the predominant products. Furthermore, the mechanisms of formation of X2 from XNO2 and XONO were also investigated. The high energy barriers of reactions and the high free energies of the products compared to those of the reactants indicate that ClNO2 is stable at the air-water interface. Contrary to the widely held belief regarding X2 producing from the reaction of XNO2 with X-, our calculations demonstrate that BrONO and IONO initially form stable BrONO···Br- and IONO···I- complexes, which then subsequently react with Br- and I- to form Br3- and I3-, respectively. Finally, Br3- and I3- decompose to form Br2 and I2. These findings have significant implications for experimental interpretation and offer new insights into halogen cycling in the atmosphere.

13.
J Am Chem Soc ; 146(29): 20494-20499, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39001838

RESUMO

The photochemistry of nitrous acid (HONO), encompassing dissociation into OH and NO as well as the reverse association reaction, plays a pivotal role in atmospheric chemistry. Here, we report the direct observation of nitrosyl-O-hydroxide (HOON) in the photochemistry of HONO, employing matrix-isolation IR and UV-vis spectroscopy. Despite a barrier of approximately 30 kJ/mol, HOON undergoes spontaneous rearrangement to the more stable HONO isomer through quantum mechanical tunneling, with a half-life of 28 min at 4 K. Kinetic isotope effects and instanton theory calculations reveal that the tunneling process involves the concerted motion of the NO moiety (65.2%) and the hydrogen atom (32.3%). Our findings underscore the significance of HOON as a key intermediate in the photolytic dissociation-association cycle of HONO at low temperatures.

14.
Br J Cancer ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39026081

RESUMO

BACKGROUND: Studies have shown that hepatitis B virus (HBV)-associated B-cell non-Hodgkin lymphoma (NHL) constitutes a unique subgroup with distinct clinical features. It still leaves open the question of whether the integration of HBV DNA into the B-cell genome is a causal mechanism in the development of lymphoma. METHODS: Using the hybridisation capture-based next generation sequencing and RNA sequencing, we characterised the HBV integration pattern in 45 HBV-associated B-cell NHL tumour tissues. RESULTS: A total of 354 HBV integration sites were identified in 13 (28.9%) samples, indicating the relatively low integration frequency in B-cell NHLs. High plasma HBV DNA loads were not associated with the existence of HBV integration. The insertion sites distributed randomly across all the lymphoma genome without any preferential hotspot neither at the chromosomal level nor at the genetic level. Intriguingly, most HBV integrations were nonclonal in B-cell NHLs, implying that they did not confer a survival advantage. Analysis of the paired diagnosis-relapse samples showed the unstable status of HBV integrations during disease progression. Furthermore, transcriptomic analysis revealed the limited biological impact of HBV integration. CONCLUSION: Our study provides an unbiased HBV integration map in B-cell NHLs, revealing the insignificant role of HBV DNA integration in B-cell lymphomagenesis.

15.
Small ; 20(27): e2311083, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38268236

RESUMO

Although metal-organic polyhedra (MOPs) expansion has been studied to date, it is still a rare occurrence for their porous intermolecular assembly for iodine capture. The major limitation is the lack of programmable and controllable methods for effectively constructing and utilizing the exterior cavities. Herein, the goal of programmable porous intermolecular assembly is realized in the first family of aluminum oxo polyhedrons (AlOPs) using ligands with directional H-bonding donor/acceptor pairs and auxiliary alcohols as structural regulation sites. The approach has the advantage of avoiding the use of expensive edge-directed ditopic and face-directed tritopic ligands in the general synthesis strategy of MOPs. Combining theoretical calculations and experiments, the intrinsic relationship is revealed between alcohol ligands and the growth mechanism of AlOPs. The maximum I2 uptake based on the mass gain during sorption corresponds to 2.35 g g-1, representing the highest reported I2 sorption by an MOP. In addition, it can be easily regenerated and maintained the iodine sorption capacity, revealing its further potential application. This method of constructing stable and programmable porous materials will provide a new way to solve problems such as radionuclide capture.

16.
Small ; 20(32): e2400615, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38477702

RESUMO

Despite the intriguing potential, nano-socketed Cu/perovskite heterostructures for CO2 electroreduction (CO2RR) are still in their infancy and rational optimization of their CO2RR properties is lacking. Here, an effective strategy is reported to promote CO2-to-C2+ conversion over nano-socketed Cu/perovskite heterostructures by A-site-valence-controlled oxygen vacancies. For the proof-of-concept catalysts of Cu/La0.3-xSr0.6+xTiO3-δ (x from 0 to 0.3), their oxygen vacancy concentrations increase controllably with the decreased A-site valences (or the increased x values). In flow cells, their activity and selectivity for C2+ present positive correlations with the oxygen vacancy concentrations. Among them, the Cu/Sr0.9TiO3-δ with most oxygen vacancies shows the optimal activity and selectivity for C2+. And relative to the Cu/La0.3Sr0.6TiO3-δ with minimum oxygen vacancies, the Cu/Sr0.9TiO3-δ exhibits marked improvements (up to 2.4 folds) in activity and selectivity for C2+. The experiments and theoretical calculations suggest that the optimized performance can be attributed to the merits provided by oxygen vacancies, including the accelerated charge transfer, enhanced adsorption/activation of reaction species, and reduced energy barrier for C─C coupling. Moreover, when explored in a membrane-electrode assembly electrolyzer, the Cu/Sr0.9TiO3-δ catalyst shows excellent activity, selectivity (43.9%), and stability for C2H4 at industrial current densities, being the most effective perovskite-based catalyst for CO2-to-C2H4 conversion.

17.
BMC Microbiol ; 24(1): 206, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858614

RESUMO

OBJECTIVE: This study aims to examine the impact of PE/PPE gene mutations on the transmission of Mycobacterium tuberculosis (M. tuberculosis) in China. METHODS: We collected the whole genome sequencing (WGS) data of 3202 M. tuberculosis isolates in China from 2007 to 2018 and investigated the clustering of strains from different lineages. To evaluate the potential role of PE/PPE gene mutations in the dissemination of the pathogen, we employed homoplastic analysis to detect homoplastic single nucleotide polymorphisms (SNPs) within these gene regions. Subsequently, logistic regression analysis was conducted to analyze the statistical association. RESULTS: Based on nationwide M. tuberculosis WGS data, it has been observed that the majority of the M. tuberculosis burden in China is caused by lineage 2 strains, followed by lineage 4. Lineage 2 exhibited a higher number of transmission clusters, totaling 446 clusters, of which 77 were cross-regional clusters. Conversely, there were only 52 transmission clusters in lineage 4, of which 9 were cross-regional clusters. In the analysis of lineage 2 isolates, regression results showed that 4 specific gene mutations, PE4 (position 190,394; c.46G > A), PE_PGRS10 (839,194; c.744 A > G), PE16 (1,607,005; c.620T > G) and PE_PGRS44 (2,921,883; c.333 C > A), were significantly associated with the transmission of M. tuberculosis. Mutations of PE_PGRS10 (839,334; c.884 A > G), PE_PGRS11 (847,613; c.1455G > C), PE_PGRS47 (3,054,724; c.811 A > G) and PPE66 (4,189,930; c.303G > C) exhibited significant associations with the cross-regional clusters. A total of 13 mutation positions showed a positive correlation with clustering size, indicating a positive association. For lineage 4 strains, no mutations were found to enhance transmission, but 2 mutation sites were identified as risk factors for cross-regional clusters. These included PE_PGRS4 (338,100; c.974 A > G) and PPE13 (976,897; c.1307 A > C). CONCLUSION: Our results indicate that some PE/PPE gene mutations can increase the risk of M. tuberculosis transmission, which might provide a basis for controlling the spread of tuberculosis.


Assuntos
Mutação , Mycobacterium tuberculosis , Polimorfismo de Nucleotídeo Único , Tuberculose , Sequenciamento Completo do Genoma , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/isolamento & purificação , China/epidemiologia , Humanos , Tuberculose/transmissão , Tuberculose/microbiologia , Tuberculose/epidemiologia , Genoma Bacteriano , Feminino , Masculino , Proteínas de Bactérias/genética , Adulto
18.
Plant Physiol ; 193(1): 448-465, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37217835

RESUMO

Bud dormancy is crucial for winter survival and is characterized by the inability of the bud meristem to respond to growth-promotive signals before the chilling requirement (CR) is met. However, our understanding of the genetic mechanism regulating CR and bud dormancy remains limited. This study identified PpDAM6 (DORMANCY-ASSOCIATED MADS-box) as a key gene for CR using a genome-wide association study analysis based on structural variations in 345 peach (Prunus persica (L.) Batsch) accessions. The function of PpDAM6 in CR regulation was demonstrated by transiently silencing the gene in peach buds and stably overexpressing the gene in transgenic apple (Malus × domestica) plants. The results showed an evolutionarily conserved function of PpDAM6 in regulating bud dormancy release, followed by vegetative growth and flowering, in peach and apple. The 30-bp deletion in the PpDAM6 promoter was substantially associated with reducing PpDAM6 expression in low-CR accessions. A PCR marker based on the 30-bp indel was developed to distinguish peach plants with non-low and low CR. Modification of the H3K27me3 marker at the PpDAM6 locus showed no apparent change across the dormancy process in low- and non-low- CR cultivars. Additionally, H3K27me3 modification occurred earlier in low-CR cultivars on a genome-wide scale. PpDAM6 could mediate cell-cell communication by inducing the expression of the downstream genes PpNCED1 (9-cis-epoxycarotenoid dioxygenase 1), encoding a key enzyme for ABA biosynthesis, and CALS (CALLOSE SYNTHASE), encoding callose synthase. We shed light on a gene regulatory network formed by PpDAM6-containing complexes that mediate CR underlying dormancy and bud break in peach. A better understanding of the genetic basis for natural variations of CR can help breeders develop cultivars with different CR for growing in different geographical regions.


Assuntos
Malus , Prunus persica , Prunus , Prunus persica/genética , Prunus persica/metabolismo , Prunus/genética , Prunus/metabolismo , Histonas/metabolismo , Estudo de Associação Genômica Ampla , Malus/genética , Regulação da Expressão Gênica de Plantas , Dormência de Plantas/genética
19.
Cardiovasc Diabetol ; 23(1): 225, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943172

RESUMO

BACKGROUND: The Triglyceride-glucose (TyG) index, a surrogate marker of insulin resistance, has been implicated in the risk of ischemic stroke. However, the interplay between TyG levels, lifestyle factors, and their collective impact on stroke risk in non-diabetic populations remains inadequately explored. This study aims to evaluate the association of ischemic stroke with the joint development of the TyG index and lifestyle in the non-diabetic population. METHODS: In this prospective cohort study, data was collected across three consecutive biennial surveys of the Kailuan Study from 2006 to 2011. The dual-trajectory model was used to determine the temporal development of TyG levels and lifestyle scores. Statistical analysis involved Cox regression models to evaluate the association between TyG-lifestyle trajectories and ischemic stroke risk, adjusting for potential confounders. RESULTS: A total of 44,403 participants were included, with five distinct TyG levels and lifestyle scores trajectory subtypes identified. In the multivariable-adjusted analyses, significant differences in ischemic stroke risk among the trajectory subtypes. Group 5, characterized by the highest TyG levels and moderate lifestyle scores, exhibited the greatest ischemic stroke risk (HR = 1.81, 95% CI: 1.51-2.18), while group 4, with moderate TyG levels and higher lifestyle scores, demonstrated the lowest risk (HR = 1.19, 95% CI: 1.04-1.37), compared with group 3. Participants with elevated TyG levels were at an increased risk of ischemic stroke in cases of pronounced insulin resistance, even with a healthy lifestyle. CONCLUSIONS: This study reveals the significant associations between the identified TyG and lifestyle trajectories and the stratification of ischemic stroke risk among non-diabetics. The TyG index is a valuable indicator for assessing insulin resistance. However, the potential benefits of lifestyle changes for those with significantly high TyG levels need to be clarified by more research to develop more effective stroke prevention strategies.


Assuntos
Biomarcadores , Glicemia , Resistência à Insulina , AVC Isquêmico , Estilo de Vida , Comportamento de Redução do Risco , Triglicerídeos , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Estudos Prospectivos , AVC Isquêmico/sangue , AVC Isquêmico/epidemiologia , AVC Isquêmico/diagnóstico , Fatores de Risco , Medição de Risco , Biomarcadores/sangue , Glicemia/metabolismo , China/epidemiologia , Idoso , Triglicerídeos/sangue , Fatores de Tempo , Adulto , Prognóstico , Estilo de Vida Saudável
20.
Chemistry ; 30(27): e202400490, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38421349

RESUMO

The diatomic molecule PH is very reactive, and it serves as the parent compound for phosphinidenes featuring a monovalent phosphorus atom. Herein, we report the characterization and reactivity of a rare hydrogen-bonded complex of PH. Specifically, the molecular complex between PH and HCl has been generated by photolysis of chlorophosphine (H2PCl) at 254 nm in a solid Ar-matrix at 10 K. The IR spectrum of the complex HP⋅⋅⋅HCl and quantum chemical calculations at the UCCSD(T)-F12a/haTZ level consistently prove that the phosphorus atom acts as a hydrogen bond acceptor with a binding energy (D0) of -0.6 kcal mol-1. In line with the observed absorption at 341 nm for the binary complex, the triplet phosphinidene PH undergoes prototype H-Cl bond insertion by reformation of H2PCl upon photoexcitation at 365 nm. However, this hydrogen-bonded complex is unstable in the presence of N2 and HCl, as both molecules prefers stronger interactions with HCl than PH in the observed complexes HP⋅⋅⋅HCl⋅⋅⋅N2 and HP⋅⋅⋅2HCl.

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