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1.
Plant Cell ; 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39121058

RESUMEN

Following whole-genome duplication (WGD), duplicate gene pairs (homoeologs) can evolve varying degrees of expression divergence. However, the determinants influencing these relative expression level differences (RFPKM) between homoeologs remain elusive. Here, we analyzed the RFPKM between homoeologs in three angiosperms, Nymphaea colorata, Nelumbo nucifera, and Acorus tatarinowii, all having undergone a single WGD since the origin of angiosperms. Our results show significant positive correlations in RFPKM of homoeologs among tissues within the same species, and among orthologs across these three species, indicating convergent expression balance/bias between homoeologous gene copies following independent WGDs. We linked RFPKM between homoeologs to gene attributes associated with dosage balance constraints, such as protein-protein interactions, lethal-phenotype scores in Arabidopsis (Arabidopsis thaliana) orthologs, domain numbers, and expression breadth. Notably, homoeologs with lower RFPKM often had more interactions and higher lethal-phenotype scores, indicating selective pressures favoring balanced expression. Also, homoeologs with lower RFPKM were more likely to be retained after WGDs in angiosperms. Within Nelumbo, greater RFPKM between homoeologs correlated with increased cis- and trans-regulatory differentiation between species, highlighting the ongoing escalation of gene expression divergence. We further found that expression degeneration in one copy of homoeologs is inclined towards nonfunctionalization. Our research highlights the importance of balanced expression, shaped by dosage balance constraints, in the evolutionary retention of homoeologs in plants.

2.
J Imaging Inform Med ; 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39020152

RESUMEN

Superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery represents the primary treatment for Moyamoya disease (MMD), with its efficacy contingent upon collateral vessel development. This study aimed to develop and validate a machine learning (ML) model for the non-invasive assessment of STA-MCA bypass surgery efficacy in MMD. This study enrolled 118 MMD patients undergoing STA-MCA bypass surgery. Clinical features were screened to construct a clinical model. MRI features were extracted from the middle cerebral artery supply area using 3D Slicer and employed to build five ML models using logistic regression algorithm. The combined model was developed by integrating the radiomics score (Rad-score) with the clinical features. Model performance validation was conducted using ROC curves. Platelet count (PLT) was identified as a significant clinical feature for constructing the clinical model. A total of 3404 features (851 × 4) were extracted, and 15 optimal features were selected from each MRI sequence as predictive factors. Multivariable logistic regression identified PLT and Rad-score as independent parameters used for constructing the combined model. In the testing set, the AUC of the T1WI ML model [0.84 (95% CI, 0.70-0.97)] was higher than that of the clinical model [0.66 (95% CI, 0.46-0.86)] and the combined model [0.80 (95% CI, 0.66-0.95)]. The T1WI ML model can be used to assess the postoperative efficacy of STA-MCA bypass surgery for MMD.

3.
Eur J Radiol ; 178: 111655, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39079324

RESUMEN

PURPOSE: To investigate the feasibility of deep learning (DL) based on conventional MRI to differentiate tuberculous spondylitis (TS) from brucellar spondylitis (BS). METHODS: A total of 383 patients with TS (n = 182) or BS (n = 201) were enrolled from April 2013 to May 2023 and randomly divided into training (n = 307) and validation (n = 76) sets. Sagittal T1WI, T2WI, and fat-suppressed (FS) T2WI images were used to construct single-sequence DL models and combined models based on VGG19, VGG16, ResNet18, and DenseNet121 network. The area under the receiver operating characteristic curve (AUC) was used to assess the classification performance. The AUC of DL models was compared with that of two radiologists with different levels of experience. RESULTS: The AUCs based on VGG19, ResNet18, VGG16, and DenseNet121 ranged from 0.885 to 0.973, 0.873 to 0.944, 0.882 to 0.929, and 0.801 to 0.933, respectively, and VGG19 models performed better. The diagnostic efficiency of combined models outperformed single-sequence DL models. The combined model of T1WI, T2WI, and FS T2WI based on VGG19 achieved optimal performance, with an AUC of 0.973. In addition, the performance of all combined models based on T1WI, T2WI, and FS T2WI was better than that of two radiologists (P<0.05). CONCLUSION: The DL models have potential guiding value in the diagnosis of TS and BS based on conventional MRI and provide a certain reference for clinical work.


Asunto(s)
Brucelosis , Aprendizaje Profundo , Imagen por Resonancia Magnética , Espondilitis , Humanos , Masculino , Femenino , Imagen por Resonancia Magnética/métodos , Espondilitis/diagnóstico por imagen , Espondilitis/microbiología , Persona de Mediana Edad , Adulto , Brucelosis/diagnóstico por imagen , Diagnóstico Diferencial , Anciano , Estudios de Factibilidad , Tuberculosis de la Columna Vertebral/diagnóstico por imagen , Algoritmos , Adulto Joven , Sensibilidad y Especificidad
4.
Front Oncol ; 14: 1389250, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38854720

RESUMEN

Background: Distinguishing between prostatic cancer (PCa) and chronic prostatitis (CP) is sometimes challenging, and Gleason grading is strongly associated with prognosis in PCa. The continuous-time random-walk diffusion (CTRW) model has shown potential in distinguishing between PCa and CP as well as predicting Gleason grading. Purpose: This study aimed to quantify the CTRW parameters (α, ß & Dm) and apparent diffusion coefficient (ADC) of PCa and CP tissues; and then assess the diagnostic value of CTRW and ADC parameters in differentiating CP from PCa and low-grade PCa from high-grade PCa lesions. Study type: Retrospective (retrospective analysis using prospective designed data). Population: Thirty-one PCa patients undergoing prostatectomy (mean age 74 years, range 64-91 years), and thirty CP patients undergoing prostate needle biopsies (mean age 68 years, range 46-79 years). Field strength/Sequence: MRI scans on a 3.0T scanner (uMR790, United Imaging Healthcare, Shanghai, China). DWI were acquired with 12 b-values (0, 50, 100, 150, 200, 500, 800, 1200, 1500, 2000, 2500, 3000 s/mm2). Assessment: CTRW parameters and ADC were quantified in PCa and CP lesions. Statistical tests: The Mann-Whitney U test was used to evaluate the differences in CTRW parameters and ADC between PCa and CP, high-grade PCa, and low-grade PCa. Spearman's correlation of the pathologic grading group (GG) with CTRW parameters and ADC was evaluated. The usefulness of CTRW parameters, ADC, and their combinations (Dm, α and ß; Dm, α, ß, and ADC) to differentiate PCa from CP and high-grade PCa from low-grade PCa was determined by logistic regression and receiver operating characteristic curve (ROC) analysis. Delong test was used to compare the differences among AUCs. Results: Significant differences were found for the CTRW parameters (α, Dm) between CP and PCa (all P<0.001), high-grade PCa, and low-grade PCa (α:P=0.024, Dm:P=0.021). GG is correlated with certain CTRW parameters and ADC(α:P<0.001,r=-0.795; Dm:P<0.001,r=-0.762;ADC:P<0.001,r=-0.790). Moreover, CTRW parameters (α, ß, Dm) combined with ADC showed the best diagnostic efficacy for distinguishing between PCa and CP as well as predicting Gleason grading. The differences among AUCs of ADC, CTRW parameters and their combinations were not statistically significant (P=0.051-0.526). Conclusion: CTRW parameters α and Dm, as well as their combination were beneficial to distinguish between CA and PCa, low-grade PCa and high-grade PCa lesions, and CTRW parameters and ADC had comparable diagnostic performance.

5.
BMC Plant Biol ; 24(1): 476, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38816799

RESUMEN

BACKGROUND: Interest in the evolution of climatic niches, particularly in understanding the potential adaptive responses of species under climate change, has increased both theoretically and within macroecological studies. These studies have provided valuable insights into how climatic traits of species influence their niche evolution. In this study, we aim to investigate whether niche conservatism plays a role in the species diversification of Nymphaea, a group of aquatic plants with a cosmopolitan distribution that is facing severe habitat loss. We will use climatic models and phylogenetic data for 23 species to reconstruct Nymphaea's niche evolution, measure niche overlap, and assess disparity through time while testing for evolutionary models. RESULTS: There was a lot of overlap in niches both within and between groups, especially for species that can be found in many places. The breadth and peaks of the niche profile varied depending on the bioclimatic variables, which suggested that the species evolved differently to cope with changes in climate. The analysis also showed that evolutionary changes happened across the phylogeny, with weak to moderate signals. The morphological disparity index (MDI) values indicated that there were disparities within subclades over time but not between or among them. Niche reconstruction and evolution analysis revealed both convergent and divergent evolution among various variables. For example, N. immutabilis, N. atrans, N. violancea, and N. nouchali evolved towards intermediate temperatures for bio2 and bio3 (isothermity) while moving towards extreme temperatures for bio8 and bio9 (wettest and driest average quarterly temperatures). CONCLUSION: Our study will improve our understanding of how changes in climatic niches are potentially driving the evolution of Nymphaea. It has significant scientific implications for the limits, assemblages, evolution, and diversification of species. This information is crucial for the ongoing efforts of conservation and management, particularly considering the inevitable effects of climate change.


Asunto(s)
Evolución Biológica , Clima , Ecosistema , Filogenia , América del Sur , Australia , África , Cambio Climático
6.
Front Med (Lausanne) ; 11: 1385998, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38698777

RESUMEN

Introduction: Remimazolam (RMZ) is a novel intravenous sedative drug of ultra-short benzodiazepine. The optimal dose of RMZ plus butorphanol for sedation during first trimester artificial abortion is unknown. Therefore, the present study aimed to evaluate the median effective dose (ED50) of RMZ combined with different doses of butorphanol on the sedative effect for first-trimester artificial abortion. Methods: Sixty-one female patients were randomly assigned to Group B10 (31 patients) and Group B15 (30 patients). RMZ was administered 5 min after IV butorphanol at doses of 10 µg/kg (Group B10) and 15 µg/kg (Group B15). Cervical dilatation at the time of using a cervical dilating rod, if the patient has body movement and affects the gynecologist's operation, we define it as "Ineffective." Therefore, the dose of RMZ was increased in the next patient. Otherwise, it was defined as "Effective," and the dose of RMZ was reduced in the next patient. According to the pre-experiment, the first dose of RMZ in the first patient was 0.35 mg/kg, and the adjacent geometric dose ratio was 0.9. The centered isotonic regression was performed to determine the ED50 of RMZ. The total RMZ dose administered, recovery time, and anesthesia-related adverse events were all recorded. Results: The ED50 (90% CI) of RMZ was 0.263 (0.215-0.310) mg/kg in Group B10, and 0.224 (0.191-0.261) mg/kg in Group B15, respectively. The recovery time in Group B10 was significantly shorter than in Group B15 (9.8 ± 2.3 vs. 12.5 ± 3.6 min, p ≤ 0.001). There was no significant difference in the incidence rate of all anesthesia-related adverse events between the two groups (p > 0.05). Conclusion: The ED50 of RMZ combined with a 10 µg/kg or 15 µg/kg dose of butorphanol was 0.263 and 0.224 mg/kg during painless first trimester artificial abortion. However, RMZ combined with a 10 µg/kg dose of butorphanol seems to have a shorter recovery time. Clinical trial registration: https://www.chictr.org.cn/bin/project/edit?pid=166623.

7.
Int Immunopharmacol ; 133: 112102, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38652971

RESUMEN

Anaplastic thyroid carcinoma (ATC) is the most aggressive subtype of thyroid cancer with few effective therapies. Though immunotherapies such as targeting PD-1/PD-L1 axis have benefited patients with solid tumor, the druggable immune checkpoints are quite limited in ATC. In our study, we focused on the anti-tumor potential of sialic acid-binding Ig-like lectins (Siglecs) in ATC. Through screening by integrating microarray datasets including 216 thyroid-cancer tissues and single-cell RNA-sequencing, SIGLEC family members CD33, SIGLEC1, SIGLEC10 and SIGLEC15 were significantly overexpressed in ATC, among which SIGLEC15 increased highest and mainly expressed on cancer cells. SIGLEC15high ATC cells are characterized by high expression of serine protease PRSS23 and cancer stem cell marker CD44. Compared with SIGLEC15low cancer cells, SIGLEC15high ATC cells exhibited higher interaction frequency with tumor microenvironment cells. Further study showed that SIGLEC15high cancer cells mainly interacted with T cells by immunosuppressive signals such as MIF-TNFRSF14 and CXCL12-CXCR4. Notably, treatment of anti-SIGLEC15 antibody profoundly increased the cytotoxic ability of CD8+ T cells in a co-culture model and zebrafish-derived ATC xenografts. Consistently, administration of anti-SIGLEC15 antibody significantly inhibited tumor growth and prolonged mouse survival in an immunocompetent model of murine ATC, which was associated with increase of M1/M2, natural killer (NK) cells and CD8+ T cells, and decrease of myeloid-derived suppressor cells (MDSCs). SIGLEC15 inhibited T cell activation by reducing NFAT1, NFAT2, and NF-κB signals. Blocking SIGLEC15 increased the secretion of IFN-γ and IL-2 in vitro and in vivo. In conclusion, our finding demonstrates that SIGLEC15 is an emerging and promising target for immunotherapy in ATC.


Asunto(s)
Inmunoterapia , Proteínas de la Membrana , Carcinoma Anaplásico de Tiroides , Neoplasias de la Tiroides , Animales , Humanos , Ratones , Antineoplásicos Inmunológicos/farmacología , Antineoplásicos Inmunológicos/uso terapéutico , Linfocitos T CD8-positivos/inmunología , Línea Celular Tumoral , Inmunoglobulinas , Inmunoterapia/métodos , Lectinas/genética , Lectinas/metabolismo , Carcinoma Anaplásico de Tiroides/terapia , Carcinoma Anaplásico de Tiroides/inmunología , Carcinoma Anaplásico de Tiroides/genética , Neoplasias de la Tiroides/terapia , Neoplasias de la Tiroides/inmunología , Neoplasias de la Tiroides/genética , Microambiente Tumoral/inmunología , Ensayos Antitumor por Modelo de Xenoinjerto
8.
J Cell Mol Med ; 28(7): e18182, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38498903

RESUMEN

Chromosome instability (CIN) is a common contributor driving the formation and progression of anaplastic thyroid cancer (ATC), but its mechanism remains unclear. The BUB1 mitotic checkpoint serine/threonine kinase (BUB1) is responsible for the alignment of mitotic chromosomes, which has not been thoroughly studied in ATC. Our research demonstrated that BUB1 was remarkably upregulated and closely related to worse progression-free survival. Knockdown of BUB1 attenuated cell viability, invasion, migration and induced cell cycle arrests, whereas overexpression of BUB1 promoted the cell cycle progression of papillary thyroid cancer cells. BUB1 knockdown remarkably repressed tumour growth and tumour formation of nude mice with ATC xenografts and suppressed tumour metastasis in a zebrafish xenograft model. Inhibition of BUB1 by its inhibitor BAY-1816032 also exhibited considerable anti-tumour activity. Further studies showed that enforced expression of BUB1 evoked CIN in ATC cells. BUB1 induced CIN through phosphorylation of KIF14 at serine1292 (Ser1292 ). Overexpression of the KIF14ΔSer1292 mutant was unable to facilitate the aggressiveness of ATC cells when compared with that of the wild type. Collectively, these findings demonstrate that the BUB1/KIF14 complex drives the aggressiveness of ATC by inducing CIN.


Asunto(s)
Carcinoma Anaplásico de Tiroides , Neoplasias de la Tiroides , Animales , Ratones , Humanos , Carcinoma Anaplásico de Tiroides/genética , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Ratones Desnudos , Pez Cebra/metabolismo , Inestabilidad Cromosómica , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Línea Celular Tumoral , Proteínas Oncogénicas/genética , Cinesinas/genética
9.
Gene ; 914: 148416, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38548188

RESUMEN

Eichhornia crassipes is an aquatic plant in tropical and subtropical regions, renowned for its notorious invasive tendencies. In this study, we assembled the complete mitogenome of E. crassipes into a single circle molecule of 397,361 bp. The mitogenome has 58 unique genes, including 37 protein-coding genes (PCGs), 18 tRNA genes, three rRNA genes, and 47 % GC content. Sixteen (6.93 %) homologous fragments, ranging from 31 bp to 8548 bp, were identified, indicating the transfer of genetic material from chloroplasts to mitochondria. In addition, we detected positive selection in six PCGs (ccmB, ccmC, ccmFC, nad3, nad4 and sdh4), along with the identification of 782 RNA editing sites across 37 mt-PCGs. These findings suggest a potential contribution to the robust adaptation of this invasive plant to the stressful environment. Lastly, we inferred that phylogenetic conflicts of E. crassipes between the plastome and mitogenome may be attributed to the difference in nucleotide substitution rates between the two organelle genomes. In conclusion, our study provided vital genomic resources for further understanding the invasive mechanism of this species and exploring the dynamic evolution of mitogenomes within the monocot clade.


Asunto(s)
Eichhornia , Genoma Mitocondrial , Filogenia , Eichhornia/genética , Especies Introducidas , ARN de Transferencia/genética , Composición de Base , Edición de ARN , Genoma de Planta
10.
Lipids Health Dis ; 23(1): 86, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38528580

RESUMEN

BACKGROUND: Acute myocardial infarction (AMI) is characterized by inflammation, oxidative stress, and atherosclerosis, contributing to increased mortality risk. High-density lipoprotein (HDL) takes a crucial part in mitigating atherosclerosis and inflammation through its diverse functionalities. Conversely, fibrinogen is implicated in the development of atherosclerotic plaques. However, the mortality risk predictive capacity of fibrinogen to HDL-cholesterol ratio (FHR) in AMI patients remains unexplored. This research aimed to evaluate the effectiveness of FHR for mortality risk prediction in relation to AMI. METHODS: A retrospective study involving 13,221 AMI patients from the Cardiorenal ImprovemeNt II cohort (NCT05050877) was conducted. Baseline FHR levels were used to categorize patients into quartiles. The assessment of survival disparities among various groups was conducted by employing Kaplan‒Meier diagram. Cox regression was performed for investigating the correlation between FHR and adverse clinical outcomes, while the Fine-Gray model was applied to evaluate the subdistribution hazard ratios for cardiovascular death. RESULTS: Over a median follow-up of 4.66 years, 2309 patients experienced all-cause death, with 1007 deaths attributed to cardiovascular disease (CVD). The hazard ratio (HR) and its 95% confidence interval (CI) for cardiac and all-cause death among individuals in the top quartile of FHR were 2.70 (1.99-3.65) and 1.48 (1.26-1.75), respectively, in comparison to ones in the first quartile, after covariate adjustment. Restricted cubic spline analysis revealed that FHR was linearly correlated with all-cause mortality, irrespective of whether models were adjusted or unadjusted (all P for nonlinearity > 0.05). CONCLUSION: AMI patients with increased baseline FHR values had higher all-cause and cardiovascular mortality, regardless of established CVD risk factors. FHR holds promise as a valuable tool for evaluating mortality risk in AMI patients. TRIAL REGISTRATION: The Cardiorenal ImprovemeNt II registry NCT05050877.


Asunto(s)
Aterosclerosis , Infarto del Miocardio , Humanos , HDL-Colesterol , Estudios Retrospectivos , Fibrinógeno , Factores de Riesgo , Inflamación
11.
Bioorg Chem ; 145: 107236, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38402796

RESUMEN

In this study, 16 new compounds, six bibenzyls (1-6) and 10 naphthalenes (7-13), including three pairs of naphthalene enantiomers and three known compounds (14-16), were isolated from Dendrobium chrysanthum. Structurally, compounds 1-5 are previously undescribed dimeric bibenzyls, uniquely linked by unusual carbon bonds. The structures of the compounds were determined using spectroscopy and X-ray crystallography. The screening results indicated that 1, 2, and 5 showed remarkable lipid-lowering activities in FFA-induced HepG2 cells, with EC50 values ranging from 3.13 to 6.57 µM. Moreover, 1, 2, and 5 significantly decreased both the mRNA and protein levels of the target SREBP-1c, and 5 also reduced PPARα mRNA and protein levels. Therefore, 1, 2, and 5 are potential drugs against hepatic steatosis by targeting PPARα or SREBP-1c.


Asunto(s)
Bibencilos , Dendrobium , Hígado Graso , Bibencilos/farmacología , Bibencilos/química , Dendrobium/química , PPAR alfa , ARN Mensajero , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Naftalenos/química , Naftalenos/farmacología
13.
Opt Lett ; 49(3): 614-617, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38300072

RESUMEN

We report an electro-optic isolator fabricated on thin-film lithium niobate by photolithography-assisted chemo-mechanical etching that shows an isolation of 39.50 dB and an overall fiber-to-fiber loss of 2.6 dB.

14.
EBioMedicine ; 100: 104962, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38184937

RESUMEN

BACKGROUND: Liver cirrhosis (LC) is the highest risk factor for hepatocellular carcinoma (HCC) development worldwide. The efficacy of the guideline-recommended surveillance methods for patients with LC remains unpromising. METHODS: A total of 4367 LCs not previously known to have HCC and 510 HCCs from 16 hospitals across 11 provinces of China were recruited in this multi-center, large-scale, cross-sectional study. Participants were divided into Stage Ⅰ cohort (510 HCCs and 2074 LCs) and Stage Ⅱ cohort (2293 LCs) according to their enrollment time and underwent Tri-phasic CT/enhanced MRI, US, AFP, and cell-free DNA (cfDNA). A screening model called PreCar Score was established based on five features of cfDNA using Stage Ⅰ cohort. Surveillance performance of PreCar Score alone or in combination with US/AFP was evaluated in Stage Ⅱ cohort. FINDINGS: PreCar Score showed a significantly higher sensitivity for the detection of early/very early HCC (Barcelona stage A/0) in contrast to US (sensitivity of 51.32% [95% CI: 39.66%-62.84%] at 95.53% [95% CI: 94.62%-96.38%] specificity for PreCar Score; sensitivity of 23.68% [95% CI: 14.99%-35.07%] at 99.37% [95% CI: 98.91%-99.64%] specificity for US) (P < 0.01, Fisher's exact test). PreCar Score plus US further achieved a higher sensitivity of 60.53% at 95.08% specificity for early/very early HCC screening. INTERPRETATION: Our study developed and validated a cfDNA-based screening tool (PreCar Score) for HCC in cohorts at high risk. The combination of PreCar Score and US can serve as a promising and practical strategy for routine HCC care. FUNDING: A full list of funding bodies that contributed to this study can be found in Acknowledgments section.


Asunto(s)
Carcinoma Hepatocelular , Ácidos Nucleicos Libres de Células , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/epidemiología , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/epidemiología , alfa-Fetoproteínas , Estudios Transversales , Detección Precoz del Cáncer/métodos , Ultrasonografía/métodos , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/complicaciones , Biomarcadores de Tumor
15.
Inorg Chem ; 63(6): 3191-3198, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38294201

RESUMEN

An AA'3B4O12-type A-site-ordered quadruple perovskite oxide AgMn7O12 was prepared by high-pressure and high-temperature methods. At room temperature, the compound crystallizes into a cubic Im3̅ symmetry with a charge distribution of AgMn33+Mn43.5+O12. With the temperature decreasing to TCO,OO ≈ 180 K, the compound undergoes a structural phase transition toward a monoclinic C2/m symmetry, giving rise to a B-site charge- and orbital-ordered AgMn33+Mn23+Mn24+O12 phase. Moreover, this charge-/orbital-ordered main phase coexists with the initial cubic AgMn33+Mn43.5+O12 phase in the wide temperature range we measured. The charge-/orbital-ordered phase shows two antiferromagnetic phase transitions near 125 and 90 K, respectively. Short-range ferromagnetic correlations are found to occur for the initial B-site mixed cubic phase around 35 K. Because of the robust phase separation, considerable magnetoresistance effects are observed below TCO,OO in AgMn7O12.

16.
DNA Res ; 31(1)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38245835

RESUMEN

Plant terrestrialization (i.e. the transition to a terrestrial environment) is a significant evolutionary event that has been intensively studied. While certain plant lineages, particularly in angiosperms, have re-adapted to freshwater habitats after colonizing terrene, however, the molecular mechanism of the terrestrial-freshwater (T-F) transition remains limited. Here, the basal monocot Araceae was selected as the study object to explore the T-F transition adaptation mechanism by comparative genomic analysis. Our findings revealed that the substitution rates significantly increased in the lineage of freshwater Araceae, which may promote their adaptation to the freshwater habitat. Additionally, 20 gene sets across all four freshwater species displayed signs of positive selection contributing to tissue development and defense responses in freshwater plants. Comparative synteny analysis showed that genes specific to submerged plants were enriched in cellular respiration and photosynthesis. In contrast, floating plants were involved in regulating gene expression, suggesting that gene and genome duplications may provide the original material for plants to adapt to the freshwater environment. Our study provides valuable insights into the genomic aspects of the transition from terrestrial to aquatic environments in Araceae, laying the groundwork for future research in the angiosperm.


Asunto(s)
Araceae , Evolución Biológica , Genoma , Agua Dulce , Plantas , Cromosomas , Filogenia
17.
Chem Asian J ; 19(6): e202301103, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38288641

RESUMEN

The development of effective and stable non-precious catalysts for hydrogenation of ester to diols remains a challenge. Herein, the catalytic hydrogenation of ethyl lactate (EL) to 1,2-propanediol (1,2-PDO) with supported Co catalysts derived from layered double hydroxides (LDHs) is investigated. Catalytic tests reveal that LDH-derived Co catalysts exhibit the best catalytic performance with 98 % of EL conversion and >99 % of 1,2-PDO selectivity at mild conditions, compared with other Co catalysts (supported on Al2O3, and TiO2) and LDH-derived Cu catalysts. Due to the strong interaction among Co and Al matrix, the main composition is metallic Co0 and CoO after reduction at 600 °C. Besides, the catalyst shows good recyclability in the liquid phase hydrogenation. The superior catalytic performance can be attributed to the synergistic effect between Co0 and CoO, in which H2 molecule is activated on Co0 and EL is strongly adsorbed on CoO via hydroxyl groups.

18.
Chemistry ; 30(12): e202303155, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38018363

RESUMEN

The rapid development of narrow-bandgap nonfullerene acceptors (NFAs) has boosted the efficiency of organic solar cells (OSCs) over 19 %. The new features of high-performance NFAs, such as visible-NIR light absorption, moderate the highest occupied molecular orbitals (HOMO), and high crystallinity, require polymer donors with matching physical properties. This emphasizes the importance of methods that can effectively tune the physical properties of polymers. Owning to very small atom size and strongest electronegativity, the fluorination has been proved the most efficient strategy to regulate the physical properties of polymer donors, including frontier energy level, absorption coefficient, dielectric constant, crystallinity and charge transport. Owing to the success of fluorination strategy, the vast majority of high-performance polymer donors possess one or more fluorine atoms. In this review, the fluorination synthetic methods, the synthetic route of well-known fluorinated building blocks, the fluorinated polymers which are categorized by the type of donor or acceptor units, and the relationships between the polymer structures, properties, and photovoltaic performances are comprehensively surveyed. We hope this review could provide the readers a deeper insight into fluorination strategy and lay a strong foundation for future innovation of fluorinated polymers.

19.
Cancer Lett ; 580: 216496, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37993084

RESUMEN

Anaplastic thyroid cancer (ATC) is one of the deadliest cancers, whose important malignant feature is dedifferentiation. Chromatin remodeling is critical for tumorigenesis and progression, while its roles and regulator in facilitating dedifferentiation of ATC had been poorly understood. In our study, an emerging function of hematological and neurological expressed 1 (HN1) in promoting dedifferentiation of ATC cells was uncovered. HN1 expression was negatively correlated with the thyroid differentiation markers both at mRNA and protein level. Knockdown of HN1 in ATC cells effectively upregulated the thyroid differentiation markers and impeded the sphere formation capacity, accompanying with the loss of cancer stemness. In contrast, overexpression of HN1 drove the gain of stemness and the loss of thyroid differentiation markers. Nude mouse and zebrafish xenograft models showed that inhibition of HN1 in ATC cells effectively hindered tumor growth due to the loss of cancer stemness. Further study showed that HN1 was negatively correlated with CTCF in an independent thyroid-cancer cohort, and inhibition of HN1 enhanced the expression of CTCF in ATC cells. Overexpression of CTCF significantly reversed the dedifferentiation phenotypes of ATC cells, whereas simultaneously inhibiting HN1 and CTCF was unable to recover the level of thyroid differentiation markers. The combination of ATAC-seq and ChIP-seq analysis confirmed that CTCF regulated genes relating with thyroid gland development through influencing their chromatin accessibility. HN1 inhibited the acetylation of H3K27 at the promoter of CTCF by recruiting HDAC2, thereby inhibiting the transcriptional activation of CTCF. These findings demonstrated an essential role of HN1 in regulating the chromatin accessibility of thyroid differentiation genes during ATC dedifferentiation.


Asunto(s)
Carcinoma Anaplásico de Tiroides , Neoplasias de la Tiroides , Animales , Humanos , Ratones , Antígenos de Diferenciación , Línea Celular Tumoral , Cromatina , Epigénesis Genética , Carcinoma Anaplásico de Tiroides/metabolismo , Neoplasias de la Tiroides/patología , Pez Cebra/genética
20.
Front Plant Sci ; 14: 1197137, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38078105

RESUMEN

Understanding how anthropogenic disturbances affect the genetics of tree species is crucial; however, how tree populations in the wild can tolerate these activities remains unexplored. Given the ongoing and intensifying anthropogenic disturbances, we conducted a study using Ailanthus altissima to gain new insights into the effects of these pressures on genetic variability in undisturbed and disturbed forests. We analyzed the genetic diversity and population structure of A. altissima using nuclear (EST-SSR) and chloroplast (cpSSR) microsatellite markers. The genetic diversity across the 34 studied populations based on EST-SSRs was found to be moderate to high (nH E = 0.547-0.772) with a mean nH E of 0.680. Bayesian clustering, principal coordinate analysis (PCoA), and discriminant analysis of principal component (DAPC) consistently divided the populations into three distinct groups based on EST-SSRs. Allelic combinations of 92 different chloroplast size variants from 10 cpSSR loci resulted in a total of 292 chloroplast haplotypes. The mean haplotype diversity was relatively high (cpH E = 0.941), and the mean haplotype richness was 2.690, averaged across the 34 populations of A. altissima. Values of F ST in A. altissima from chloroplast and nuclear markers were 0.509 and 0.126, respectively. Modeling results showed evidence for population range contraction during the Last Glacial Maximum with subsequent population expansion in the Holocene and the future. Although genetic variation did not differ substantially across disturbed and undisturbed sites, there were small trends indicating higher genetic diversity and population bottlenecks in disturbed forests. As a result, disrupted ecosystems might display surprising genetic patterns that are difficult to predict and should not be overlooked.

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