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1.
BMC Gastroenterol ; 24(1): 137, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38641789

ABSTRACT

OBJECTIVE: Prediction of lymph node metastasis (LNM) for intrahepatic cholangiocarcinoma (ICC) is critical for the treatment regimen and prognosis. We aim to develop and validate machine learning (ML)-based predictive models for LNM in patients with ICC. METHODS: A total of 345 patients with clinicopathological characteristics confirmed ICC from Jan 2007 to Jan 2019 were enrolled. The predictors of LNM were identified by the least absolute shrinkage and selection operator (LASSO) and logistic analysis. The selected variables were used for developing prediction models for LNM by six ML algorithms, including Logistic regression (LR), Gradient boosting machine (GBM), Extreme gradient boosting (XGB), Random Forest (RF), Decision tree (DT), Multilayer perceptron (MLP). We applied 10-fold cross validation as internal validation and calculated the average of the areas under the receiver operating characteristic (ROC) curve to measure the performance of all models. A feature selection approach was applied to identify importance of predictors in each model. The heat map was used to investigate the correlation of features. Finally, we established a web calculator using the best-performing model. RESULTS: In multivariate logistic regression analysis, factors including alcoholic liver disease (ALD), smoking, boundary, diameter, and white blood cell (WBC) were identified as independent predictors for LNM in patients with ICC. In internal validation, the average values of AUC of six models ranged from 0.820 to 0.908. The XGB model was identified as the best model, the average AUC was 0.908. Finally, we established a web calculator by XGB model, which was useful for clinicians to calculate the likelihood of LNM. CONCLUSION: The proposed ML-based predicted models had a good performance to predict LNM of patients with ICC. XGB performed best. A web calculator based on the ML algorithm showed promise in assisting clinicians to predict LNM and developed individualized medical plans.


Subject(s)
Bile Duct Neoplasms , Cholangiocarcinoma , Humans , Lymphatic Metastasis , Models, Statistical , Prognosis , Machine Learning , Bile Ducts, Intrahepatic
2.
World J Clin Cases ; 12(11): 1857-1862, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38660559

ABSTRACT

In this editorial, we comment on an article by Ruan et al published in a recent issue of the World Journal of Clinical Case. Pulmonary meningothelial proliferative lesions, including primary pulmonary meningiomas, minute pulmonary meningothelial-like nodules, and metastatic pulmonary meningiomas are rare pulmonary lesions. These lesions are difficult to differentiate from lung cancers based on clinical and imaging manifestations. Herein, we briefly introduce the clinical, imaging, and pathological characteristics of these lesions and discuss their pathogenesis to strengthen the current understanding of pulmonary meningothelial proliferative lesions in clinical diagnosis and therapy.

3.
World J Gastrointest Oncol ; 16(4): 1180-1191, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38660654

ABSTRACT

Esophageal cancer ranks among the most prevalent malignant tumors globally, primarily due to its highly aggressive nature and poor survival rates. According to the 2020 global cancer statistics, there were approximately 604000 new cases of esophageal cancer, resulting in 544000 deaths. The 5-year survival rate hovers around a mere 15%-25%. Notably, distinct variations exist in the risk factors associated with the two primary histological types, influencing their worldwide incidence and distribution. Squamous cell carcinoma displays a high incidence in specific regions, such as certain areas in China, where it meets the cost-effectiveness criteria for widespread endoscopy-based early diagnosis within the local population. Conversely, adenocarcinoma (EAC) represents the most common histological subtype of esophageal cancer in Europe and the United States. The role of early diagnosis in cases of EAC originating from Barrett's esophagus (BE) remains a subject of controversy. The effectiveness of early detection for EAC, particularly those arising from BE, continues to be a debated topic. The variations in how early-stage esophageal carcinoma is treated in different regions are largely due to the differing rates of early-stage cancer diagnoses. In areas with higher incidences, such as China and Japan, early diagnosis is more common, which has led to the advancement of endoscopic methods as definitive treatments. These techniques have demonstrated remarkable efficacy with minimal complications while preserving esophageal functionality. Early screening, prompt diagnosis, and timely treatment are key strategies that can significantly lower both the occurrence and death rates associated with esophageal cancer.

4.
Chemistry ; : e202304234, 2024 Apr 21.
Article in English | MEDLINE | ID: mdl-38644695

ABSTRACT

With both TEMPO and O2 (in air) as the homogeneous redox mediators, BiBrO as the heterogeneous semiconductor photocatalyst, the first example of semi-heterogeneous photocatalytic decarboxylative phosphorylation of N-arylglycines with diarylphosphine oxides was established. A series of α-amino phosphinoxides were efficiently synthesized.

5.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1621-1631, 2024 Mar.
Article in Chinese | MEDLINE | ID: mdl-38621947

ABSTRACT

Network pharmacology was employed to probe into the mechanism of Fushen Granules in treating peritoneal dialysis-rela-ted peritonitis(PDRP) in rats. The main active components of Fushen Granules were searched against the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform, and their targets were predicted. PDRP-related targets were retrieved from DisGeNET and other databases. The common targets shared by the drug and the disease were identified by the online tool, and protein-protein interaction(PPI) network of the common targets. The obtained 276 common targets were imported into DAVID for GO function enrichment and KEGG pathway enrichment. The main signaling pathway of Fushen Granules in the treatment of PDRP was predicted as Toll-like receptor 4(TLR4)/nuclear factor(NF)-κB. The rat model of uremia was induced by 5/6 nephrectomy. From two weeks after operation, the rat model of peritoneal dialysis(PD) was established by intraperitoneal injection of 20 mL dialysate with 1.25% glucose every day. The sham operation group and model group received 2 mL normal saline by gavage every day. The rats in Fushen Gra-nules groups were administrated with 2 mL solutions of low-(0.54 g·kg~(-1)), medium-(1.08 g·kg~(-1)) and high-dose(2.16 g·kg~(-1)) Fushen Granules every day. The bifico group received 2 mL(113.4 mg·kg~(-1)) of bifico solution every day. At the end of the 8th week, the levels of serum creatinine(Scr) and blood urea nitrogen(BUN) in each group were measured. The serum levels of hypersensitive C reactive protein(hs-CRP), tumor necrosis factor(TNF)-α, and interleukin(IL)-6 were measured, and the pathological changes in the colon tissue were observed by hematoxylin-eosin(HE) staining. The serum levels of lipopolysaccharide(LPS) and lipopolysaccharide-binding protein(LBP) of rats were measured, and the expression levels of LBP, TLR4, NF-κB p65, inhibitor of κB kinase α(IκBα), TNF-α, and IL-1ß in the colon tissue were determined. Compared with sham operation group, the model group had abnormal structure of all layers of colon tissue, sparse and shorter intestinal villi, visible edema in mucosal layer, wider gap, obvious local inflammatory cell infiltration, significantly decreased body weight(P<0.01), and significantly increased kidney function index(Scr, BUN) content(P<0.01). Serum levels of inflammatory cytokines(hs-CRP, TNF-α, IL-6), LPS and LBP were significantly increased(P<0.01), protein expressions of LBP, TLR4, NF-κB p65, TNF-α and IL-1ß were significantly increased(P<0.01), and protein expressions of IκBα were significantly decreased(P<0.01). Compared with model group, intestinal villi damage in colonic tissue of rats in low-, medium-and high-dose Fushen Granules groups and bifico group were alleviated to different degrees, edema in submucosa was alleviated, space was narrowed, and inflammatory cell infiltration in lamina propria was reduced. The contents of renal function index(Scr, BUN) and serum inflammatory factors(hs-CRP, TNF-α, IL-6) were significantly decreased(P<0.05 or P<0.01) in medium-and high-dose Fushen Granules groups and bifico group(P<0.05 or P<0.01). Serum LPS and LBP contents in Fushen Granules group and bifico group were significantly decreased(P<0.01), protein expressions of LBP, TLR4, NF-κB p65, TNF-α and IL-1ß in Fushen Granules group were significantly decreased(P<0.05 or P<0.01), and protein expressions of IκBα were significantly increased(P<0.01). The expression of LBP protein in bifico group was significantly decreased(P<0.01). The results suggest that Fushen Granules can protect the residual renal function of PD rats, reduce the inflammatory response, and protect the colon tissue. Based on network pharmacology, TLR4/NF-κB pathway may be the main signaling pathway of Fushen granule in the treatment of PDRP. The results showed that Fushen Granules could improve intestinal inflammation and protect intestinal barrier to prevent PDRP by regulating the expression of key factors in TLR4/NF-κB pathway in colon of PD rats.


Subject(s)
Animal Experimentation , Peritoneal Dialysis , Peritonitis , Rats , Animals , NF-kappa B/genetics , NF-kappa B/metabolism , NF-KappaB Inhibitor alpha , Network Pharmacology , Tumor Necrosis Factor-alpha/metabolism , C-Reactive Protein , Toll-Like Receptor 4/genetics , Toll-Like Receptor 4/metabolism , Interleukin-6 , Lipopolysaccharides , Peritonitis/drug therapy , Peritoneal Dialysis/adverse effects , Edema
6.
Mycopathologia ; 189(3): 35, 2024 Apr 18.
Article in English | MEDLINE | ID: mdl-38637433

ABSTRACT

Candida auris, an emerging and multidrug-resistant fungal pathogen, has led to numerous outbreaks in China. While the resistance mechanisms against azole and amphotericin B have been studied, the development of drug resistance in this pathogen remains poorly understood, particularly in in vivo-generated drug-resistant strains. This study employed pathogen whole-genome sequencing to investigate the epidemiology and drug-resistance mutations of C. auris using 16 strains isolated from two patients. Identification was conducted through Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and antimicrobial susceptibilities were assessed using broth microdilution and Sensititre YeastOne YO10. Whole-genome sequencing revealed that all isolates belonged to the South Asian lineage, displaying genetic heterogeneity. Despite low genetic variability among patient isolates, notable mutations were identified, including Y132F in ERG11 and A585S in TAC1b, likely linked to increased fluconazole resistance. Strains from patient B also carried F214L in TAC1b, resulting in a consistent voriconazole minimum inhibitory concentration of 4 µg/mL across all isolates. Furthermore, a novel frameshift mutation in the SNG1 gene was observed in amphotericin B-resistant isolates compared to susceptible ones. Our findings suggest the potential transmission of C. auris and emphasize the need to explore variations related to antifungal resistance. This involves analyzing genomic mutations and karyotypes, especially in vivo, to compare sensitive and resistant strains. Further monitoring and validation efforts are crucial for a comprehensive understanding of the mechanisms of drug resistance in C. auris.


Subject(s)
Antifungal Agents , Candidiasis , Humans , Antifungal Agents/pharmacology , Candidiasis/microbiology , Candida auris , Candida , Amphotericin B/pharmacology , Drug Resistance, Fungal/genetics , Microbial Sensitivity Tests
7.
JACS Au ; 4(3): 1207-1218, 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38559717

ABSTRACT

Catalyst design for the efficient CO2 reduction reaction (CO2RR) remains a crucial challenge for the conversion of CO2 to fuels. Natural Ni-Fe carbon monoxide dehydrogenase (NiFe-CODH) achieves reversible conversion of CO2 and CO at nearly thermodynamic equilibrium potential, which provides a template for developing CO2RR catalysts. However, compared with the natural enzyme, most biomimetic synthetic Ni-Fe complexes exhibit negligible CO2RR catalytic activities, which emphasizes the significance of effective bimetallic cooperation for CO2 activation. Enlightened by bimetallic synergy, we herein report a dinickel complex, NiIINiII(bphpp)(AcO)2 (where NiNi(bphpp) is derived from H2bphpp = 2,9-bis(5-tert-butyl-2-hydroxy-3-pyridylphenyl)-1,10-phenanthroline) for electrocatalytic reduction of CO2 to CO, which exhibits a remarkable reactivity approximately 5 times higher than that of the mononuclear Ni catalyst. Electrochemical and computational studies have revealed that the redox-active phenanthroline moiety effectively modulates the electron injection and transfer akin to the [Fe3S4] cluster in NiFe-CODH, and the secondary Ni site facilitates the C-O bond activation and cleavage through electron mediation and Lewis acid characteristics. Our work underscores the significant role of bimetallic cooperation in CO2 reduction catalysis and provides valuable guidance for the rational design of CO2RR catalysts.

8.
Cell Mol Biol (Noisy-le-grand) ; 70(3): 136-141, 2024 Mar 31.
Article in English | MEDLINE | ID: mdl-38650143

ABSTRACT

This study aimed to explore the core genes of craniopharyngioma angiogenesis for targeted vascular therapy based on single-cell nuclear transcriptome sequencing. For single-cell nuclear transcriptome sequencing, we collected six samples from the tumor center and adjacent hypothalamic tumor tissues from three patients with craniopharyngioma, as well as four normal brain tissues based on Gene Expression Omnibus. We screened genes with differential up-regulation between vascular endothelial cells of craniopharyngioma and those of normal brain tissues, performed GO and KEGG analysis, constructed the protein-protein interaction network, and selected key genes verified using immunofluorescence. After data cleaning and quality control, 623 craniopharyngioma endothelial cells and 439 healthy brain endothelial cells were obtained. Compared with normal brain endothelial cells, craniopharyngioma endothelial cells were screened for 394 differentially up-expressed genes (DEGs). GO and KEGG results showed that DEGs probably modulated endothelial cells, adherens junction, focal adhesion, migration, actin cytoskeleton, and invasion via the PI3K-AKT, Rap1, Ras, Wnt, and Hippo pathways. The core genes screened were CTNNB1, PTK2, ITGB1, STAT3, FYN, HIF1A, VCL, SMAD3, PECAM1, FOS, and CDH5. This study obtained possible anti-angiogenic genes in craniopharyngioma. Our results shed novel insights into molecular mechanisms and craniopharyngioma treatment.

9.
Oncogene ; 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38654109

ABSTRACT

Mammalian target of rapamycin (mTOR) kinase functions as a central regulator of cell growth and metabolism, and its complexes mTORC1 and mTORC2 phosphorylate distinct substrates. Dysregulation of mTOR signaling is commonly implicated in human diseases, including cancer. Despite three decades of active research in mTOR, much remains to be determined. Here, we demonstrate that prolyl 4-hydroxylase alpha-2 (P4HA2) binds directly to mTOR and hydroxylates one highly conserved proline 2341 (P2341) within a kinase domain of mTOR, thereby activating mTOR kinase and downstream effector proteins (e.g. S6K and AKT). Moreover, the hydroxylation of P2341 strengthens mTOR stability and allows mTOR to accurately recognize its substrates such as S6K and AKT. The growth of lung adenocarcinoma cells overexpressing mTORP2341A is significantly reduced when compared with that of cells overexpressing mTORWT. Interestingly, in vivo cell growth assays show that targeting P4HA2-mTOR significantly suppresses lung adenocarcinoma cell growth. In summary, our study reveals an undiscovered hydroxylation-regulatory mechanism by which P4HA2 directly activates mTOR kinase, providing insights for therapeutically targeting mTOR kinase-driven cancers.

10.
J Environ Manage ; 358: 120855, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38614007

ABSTRACT

Political conflicts or geopolitical tensions can create uncertainty in addressing climate change and environmental management in the Arctic. Dissecting how actors interact with each other and form networks is important for understanding ecological and environmental management challenges during geopolitical tensions, as well as promoting better governance. We construct transboundary networks for Arctic climate change governance (ACCG) from 2013 to 2021 based on the Global Database of Events, Language, and Tone (GDELT). Further, we used network descriptive statistical analysis and Temporal Exponential Random Graph Models (TERGM) to explore the structure of ACCG networks and the key factors influencing cooperation formation. The findings suggest that the overall cooperation density of the ACCG is low, and the dominant position of core actors is continuously strengthening. Non-state actors are less likely to be seen as partners and their participation depends largely on cooperation with states. The results also show that actors with similar stances and problem exposure are more likely to cooperate, but those exposed to high latitudes often choose not to cooperate; first-comers are more likely to perceive as cooperating yet they are inclined to establish internal cooperation. Additionally, two geographically proximate actors are more likely to cooperate. This indicates that under geopolitical tensions, the ACCG faces challenges not only due to the limited capacity of non-state actors to perform transboundary functions but also because the cooperation mechanisms are influenced by regional political logic. Accordingly, we further suggest policy recommendations from developing binding international frameworks to guide transboundary cooperation, enhancing cooperation among non-state actors, and ensuring the representativeness and fairness of non-Arctic actors' participation. This research provides insights into transboundary environmental management under political tensions, while also offering new pathways for analysing large-scale environmental governance structures.

11.
bioRxiv ; 2024 Mar 31.
Article in English | MEDLINE | ID: mdl-38585720

ABSTRACT

The subcommissural organ (SCO) is a gland located at the entrance of the aqueduct of Sylvius in the brain. It exists in species as distantly related as amphioxus and humans, but its function is largely unknown. To explore its function, we compared transcriptomes of SCO and non-SCO brain regions and found three genes, Sspo, Car3, and Spdef, that are highly expressed in the SCO. Mouse strains expressing Cre recombinase from endogenous promoter/enhancer elements of these genes were used to genetically ablate SCO cells during embryonic development, resulting in severe hydrocephalus and defects in neuronal migration and development of neuronal axons and dendrites. Unbiased peptidomic analysis revealed enrichment of three SCO-derived peptides, namely thymosin beta 4, thymosin beta 10, and NP24, and their reintroduction into SCO-ablated brain ventricles substantially rescued developmental defects. Together, these data identify a critical role for the SCO in brain development.

12.
Nat Commun ; 15(1): 3050, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38594237

ABSTRACT

Supramolecular polymeric materials have exhibited attractive features such as self-healing, reversibility, and stimuli-responsiveness. However, on account of the weak bonding nature of most noncovalent interactions, it remains a great challenge to construct supramolecular polymeric materials with high robustness. Moreover, high usage of supramolecular units is usually necessary to promote the formation of robust supramolecular polymeric materials, which restrains their applications. Herein, we describe the construction of highly robust supramolecular polymer networks by using only a tiny amount of metallacycles as the supramolecular crosslinkers. A norbornene ring-opening metathesis copolymer with a 120° dipyridine ligand is prepared and self-assembled with a 60° or 120° Pt(II) acceptor to fabricate the metallacycle-crosslinked polymer networks. With only 0.28 mol% or less pendant dipyridine units to form the metallacycle crosslinkers, the mechanical properties of the polymers are significantly enhanced. The tensile strengths, Young's moduli, and toughness of the reinforced polymers reach up to more than 20 MPa, 600 MPa, and 150 MJ/m3, respectively. Controllable destruction and reconstruction of the metallacycle-crosslinked polymer networks are further demonstrated by the sequential addition of tetrabutylammonium bromide and silver triflate, indicative of good stimuli-responsiveness of the networks. These remarkable performances are attributed to the thermodynamically stable, but dynamic metallacycle-based supramolecular coordination complexes that offer strong linkages with good adaptive characteristics.

13.
World J Gastroenterol ; 30(10): 1291-1294, 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38596490

ABSTRACT

In recent years, endoscopic resection, particularly endoscopic submucosal dissection, has become increasingly popular in treating non-metastatic superficial esophageal squamous cell carcinoma (ESCC). In this evolving paradigm, it is crucial to identify factors that predict higher rates of lymphatic invasion and poorer outcomes. Larger tumor size, deeper invasion, poorer differentiation, more infiltrative growth patterns (INF-c), higher-grade tumor budding, positive lymphovascular invasion, and certain biomarkers have been associated with lymph node metastasis and increased morbidity through retrospective reviews, leading to the construction of comprehensive nomograms for outcome prediction. If validated by future prospective studies, these nomograms would prove highly applicable in guiding the selection of treatment for superficial ESCC.


Subject(s)
Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Humans , Esophageal Squamous Cell Carcinoma/surgery , Esophageal Squamous Cell Carcinoma/pathology , Nomograms , Esophageal Neoplasms/surgery , Esophageal Neoplasms/pathology , Prospective Studies , Retrospective Studies , Prognosis
14.
Immunol Invest ; : 1-22, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38622991

ABSTRACT

Osteoarthritis (OA) is now widely acknowledged as a low-grade inflammatory condition, in which the intrinsic immune system plays a significant role in its pathogenesis. While the involvement of macrophages and T cells in the development of OA has been extensively reviewed, recent research has provided mounting evidence supporting the crucial contribution of NK cells in both the initiation and advancement of OA. Accumulated evidence has emerged in recent years indicating that NK cells play a critical role in OA development and progression. This review will outline the ongoing understanding of the utility of NK cells in the etiology of OA, focusing on how NK cells interact with chondrocytes, synoviocytes, osteoclasts, and other immune cells to influence the course of OA disease.

15.
World J Gastrointest Surg ; 16(2): 503-510, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38463365

ABSTRACT

BACKGROUND: Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment, the feasibility and safety of this approach for laparoscopic pancreaticoduodenectomy (LPD) require further clinical evaluation and investigation. AIM: To explore the application value of the "five steps four quadrants" modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in LPD patients. METHODS: A total of 52 patients who underwent LPD via the "five steps four quadrants" modularized en bloc dissection technique for hepatic hilum lymph nodes from April 2021 to July 2023 in our department were analyzed retrospectively. The patients' body mass index (BMI), preoperative laboratory indices, intraoperative variables and postoperative complications were recorded. The relationships between preoperative data and intraoperative lymph node dissection time and blood loss were also analyzed. RESULTS: Among the 52 patients, 36 were males and 16 were females, and the average age was 62.2 ± 11.0 years. There were 26 patients with pancreatic head cancer, 16 patients with periampullary cancer, and 10 patients with distal bile duct cancer. The BMI was 22.3 ± 3.3 kg/m², and the median total bilirubin (TBIL) concentration was 57.7 (16.0-155.7) µmol/L. All patients successfully underwent the "five steps four quadrants" modularized en bloc dissection technique without lymph node clearance-related complications such as postoperative bleeding or lymphatic leakage. Correlation analysis revealed significant associations between preoperative BMI (r = 0.3581, P = 0.0091), TBIL level (r = 0.2988, P = 0.0341), prothrombin time (r = 0.3018, P = 0.0297) and lymph node dissection time. Moreover, dissection time was significantly correlated with intraoperative blood loss (r = 0.7744, P < 0.0001). Further stratified analysis demonstrated that patients with a preoperative BMI ≥ 21.9 kg/m² and a TIBL concentration ≥ 57.7 µmol/L had significantly longer lymph node dissection times (both P < 0.05). CONCLUSION: The "five steps four quadrants" modularized en bloc dissection technique for accessing the hepatic hilum lymph node is safe and feasible for LPD. This technique is expected to improve the efficiency of hepatic hilum lymph node dissection and shorten the learning curve; thus, it is worthy of further clinical promotion and application.

17.
J Org Chem ; 89(6): 4113-4119, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38448366

ABSTRACT

The first example of an electrochemical multicomponent synthesis of selenium-containing compounds with inexpensive and abundant elemental selenium as the selenating reagent was developed. A variety of selenazol-2-amines were constructed in high yields with good functional group tolerance under metal-free and chemical oxidant-free conditions.

18.
Nat Commun ; 15(1): 2298, 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38485742

ABSTRACT

Magnetic resonance imaging (MRI) has diverse applications in physics, biology, and medicine. Uniform excitation of nuclei spins through circular-polarized transverse magnetic component of electromagnetic field is vital for obtaining unbiased tissue contrasts. However, achieving this in the electrically large human body poses a significant challenge, especially at ultra-high fields (UHF) with increased working frequencies (≥297 MHz). Canonical volume resonators struggle to meet this challenge, while radiative excitation methods like travelling-wave (TW) show promise but often suffer from inadequate excitation efficiency. Here, we introduce a new technique using a subwavelength dielectric waveguide insert that enhances both efficiency and homogeneity at 7 T. Through TE11-to-TM11 mode conversion, power focusing, wave impedance matching, and phase velocity matching, we achieved a 114% improvement in TW efficiency and mitigated the center-brightening effect. This fundamental advancement in TW MRI through effective wave manipulation could promote the electromagnetic design of UHF MRI systems.

19.
Plant Commun ; : 100878, 2024 Mar 11.
Article in English | MEDLINE | ID: mdl-38475995

ABSTRACT

Brassicaceae represents an important plant family from both a scientific and economic perspective. However, genomic features related to the early diversification of this family have not been fully characterized, especially upon the uplift of the Tibetan Plateau, which was followed by increasing aridity in the Asian interior, intensifying monsoons in Eastern Asia, and significantly fluctuating daily temperatures. Here, we reveal the genomic architecture that accompanied early Brassicaceae diversification by analyzing two high-quality chromosome-level genomes for Meniocus linifolius (Arabodae; clade D) and Tetracme quadricornis (Hesperodae; clade E), together with genomes representing all major Brassicaceae clades and the basal Aethionemeae. We reconstructed an ancestral core Brassicaceae karyotype (CBK) containing 9 pseudochromosomes with 65 conserved syntenic genomic blocks and identified 9702 conserved genes in Brassicaceae. We detected pervasive conflicting phylogenomic signals accompanied by widespread ancient hybridization events, which correlate well with the early divergence of core Brassicaceae. We identified a successive Brassicaceae-specific expansion of the class I TREHALOSE-6-PHOSPHATE SYNTHASE 1 (TPS1) gene family, which encodes enzymes with essential regulatory roles in flowering time and embryo development. The TPS1s were mainly randomly amplified, followed by expression divergence. Our results provide fresh insights into historical genomic features coupled with Brassicaceae evolution and offer a potential model for broad-scale studies of adaptive radiation under an ever-changing environment.

20.
Langmuir ; 40(14): 7692-7700, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38546150

ABSTRACT

Porous thermosensitive hydrogels exhibit a more flexible strategy for freshwater capture compared to conventional hydrogels. This study employs molecular dynamics (MD) simulation to investigate the deswelling behavior of poly(N-isopropylacrylamide) (PNIPAM) grafted within the nanochannel, aiming to elucidate the deswelling elimination process at various temperatures. Notably, a distinct phase separation is observed at specific temperatures above the lower solution temperature (LCST). Furthermore, this study takes the effect of heat flux into account, wherein distinct heat fluxes lead to varying levels of phase separation between water and the polymer. Specifically, the number of hydrogen bonds, volume of polymer chains, and density distribution of water molecules are statistically analyzed to reveal the mechanism of phase separation in a thermosensitive hydrogel. These findings provide insight into the accelerated deswelling kinetics of the PNIPAM polymer chain, which has guiding significance for the field of water harvesting by the enhancement of the water release capacity in thermosensitive hydrogels.

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