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1.
World J Gastrointest Surg ; 16(9): 2942-2952, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39351558

RESUMEN

BACKGROUND: Gastrointestinal stromal tumors (GISTs) vary widely in prognosis, and traditional pathological assessments often lack precision in risk stratification. Advanced imaging techniques, especially magnetic resonance imaging (MRI), offer potential improvements. This study investigates how MRI imagomics can enhance risk assessment and support personalized treatment for GIST patients. AIM: To assess the effectiveness of MRI imagomics in improving GIST risk stratification, addressing the limitations of traditional pathological assessments. METHODS: Analyzed clinical and MRI data from 132 GIST patients, categorizing them by tumor specifics and dividing into risk groups. Employed dimension reduction for optimal imagomics feature selection from diffusion-weighted imaging (DWI), T1-weighted imaging (T1WI), and contrast enhanced T1WI with fat saturation (CE-T1WI) fat suppress (fs) sequences. RESULTS: Age, lesion diameter, and mitotic figures significantly correlated with GIST risk, with DWI sequence features like sphericity and regional entropy showing high predictive accuracy. The combined T1WI and CE-T1WI fs model had the best predictive efficacy. In the test group, the DWI sequence model demonstrated an area under the curve (AUC) value of 0.960 with a sensitivity of 80.0% and a specificity of 100.0%. On the other hand, the combined performance of the T1WI and CE-T1WI fs models in the test group was the most robust, exhibiting an AUC value of 0.834, a sensitivity of 70.4%, and a specificity of 85.2%. CONCLUSION: MRI imagomics, particularly DWI and combined T1WI/CE-T1WI fs models, significantly enhance GIST risk stratification, supporting precise preoperative patient assessment and personalized treatment plans. The clinical implications are profound, enabling more accurate surgical strategy formulation and optimized treatment selection, thereby improving patient outcomes. Future research should focus on multicenter studies to validate these findings, integrate advanced imaging technologies like PET/MRI, and incorporate genetic factors to achieve a more comprehensive risk assessment.

2.
J Clin Oncol ; : JCO2301296, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39353160

RESUMEN

PURPOSE: Screening for nasopharyngeal carcinoma (NPC) has shown an improvement in early detection and survival rates of NPC in endemic regions. It is critical to evaluate whether NPC screening can reduce NPC-specific mortality in the population. METHODS: Sixteen towns in Sihui and Zhongshan cities, China, were selected; eight were randomly allocated to the screening group and eight to the control group. Residents age 30-69 years with no history of NPC were included from January 1, 2008, to December 31, 2015. Residents in the screening towns were invited to undergo serum Epstein-Barr virus (EBV) viral capsid antigen/nuclear antigen 1-immunoglobulin A antibody tests; others received no intervention. The population was followed until December 31, 2019. Nonparametric tests and Poisson regression models were used to estimate the screening effect on NPC mortality, accounting for the cluster-randomized design. The trial is registered with ClinicalTrials.gov (identifier: NCT00941538). RESULTS: A total of 174,943 residents in the screening group and 186,263 residents in the control group were included. NPC incidence and overall mortality were similar between the two groups. A total of 52,498 (30.0% of 174,943) residents participated in the serum EBV antibody test. The overall compliance rate for endoscopic examination and/or biopsies among baseline and ever-classified high-risk participants was 65.9% (1,110 of 1,685) and 67.6% (1,703 of 2,518), respectively. A significant 30% reduction in NPC mortality was observed in the screening group compared with the control group (standardized NPC-specific mortality rate of 8.2 NPC deaths per 1,000 person-years versus 12.5; adjusted rate ratio [RR], 0.70 [95% CI, 0.49 to 0.997]; P = .048). This benefit was most evident among individuals age 50 years and older (RR, 0.56 [95% CI, 0.37 to 0.85]; P = .007) compared with those younger than 50 years (RR, 0.96 [95% CI, 0.64 to 1.46]; P = .856). CONCLUSION: In this 12-year trial, EBV antibody testing resulted in a significant reduction in NPC mortality.

3.
Pestic Biochem Physiol ; 204: 106083, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39277396

RESUMEN

Eleusine indica is one of the most troublesome weeds in farmland worldwide, especially in Citrus Orchard of China. Glufosinate, as an efficient non-selective broad-spectrum herbicide, has been widely utilized for the control of E. indica in Citrus Orchard. The E. indica resistant population (R) was collected from a Citrus Orchard in Yichang City in Hubei province, China. Bioassay experiments showed that the R plants exhibited 3-fold resistance to glufosinate compared with the E. indica susceptible population (S). No known glutamine synthetase (GS) gene mutation associated with glufosinate resistance was found in R plants. And there was also no significant difference in GS activity between R and S plants. Those results indicated that the resistance to glufosinate in R did not involve target-site resistance. However, glutathione S-transferase (GST) inhibitor 4-chloro-7-nitrobenzoxadiazole (NBD-Cl) plus glufosinate gave a better control of R plants compared with glufosinate treatment alone. Moreover, both before and after glufosinate treatment, the GST activity in R plants was significantly higher than that in S plants. By RNA-seq, the expression of GSTU6 and GST4 up-regulated in R plants relative to S plants with or without glufosinate treatment. They were also significantly up-regulated expression in E. indica field resistant populations compared with S population. In summary, the study elucidated that R plants developed metabolic resistance to glufosinate involving GST. And GSTU6 and GST4 genes may play an important role in this glufosinate metabolic resistance. The research results provide a theoretical basis for a deeper understanding of resistance mechanism to glufosinate in E. indica.


Asunto(s)
Aminobutiratos , Eleusine , Resistencia a los Herbicidas , Herbicidas , Aminobutiratos/farmacología , Herbicidas/farmacología , Resistencia a los Herbicidas/genética , Eleusine/genética , Eleusine/metabolismo , Eleusine/efectos de los fármacos , Glutatión Transferasa/metabolismo , Glutatión Transferasa/genética , Glutamato-Amoníaco Ligasa/metabolismo , Glutamato-Amoníaco Ligasa/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
4.
Toxics ; 12(9)2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39330574

RESUMEN

Inflammation is associated with an increased risk of developing various cancers in both animals and humans, primarily solid tumors but also myeloproliferative neoplasms (MPNs), myelodysplastic syndromes (MDS), and acute myeloid leukemia (AML). Multi-walled carbon nanotubes (MWCNTs), a type of carbon nanotubes (CNTs) increasingly used in medical research and other fields, are leading to a rising human exposure. Our study demonstrated that exposing mice to MWCNTs accelerated the progression of spontaneous MOL4070LTR virus-induced leukemia. Additionally, similar exposures elevated pro-inflammatory cytokines such as interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α and induced reactive oxygen species (ROS) in a murine macrophage cell line. These effects were significantly reduced in immunodeficient mice and when mice were treated with methoxypolyethylene glycol amine (PEG)-modified MWCNTs. These findings underscore the necessity of evaluating the safety of MWCNTs, particularly for those with hematologic cancers.

5.
Ying Yong Sheng Tai Xue Bao ; 35(6): 1483-1491, 2024 Jun.
Artículo en Chino | MEDLINE | ID: mdl-39235005

RESUMEN

Studies on niche and interspecific association can reveal plant interspecific relationship in the community, and provide theoretical support for promoting the transformation and development of plantation to natural forest. Based on Cunninghamia lanceolata investigation data of permanent plots of plantation in Jianfengling area of Hainan Tropical Rainforest National Park, we analyzed niche and interspecific association of the top 20 woody species in the community according to their importance values. The results showed that there were 163 species of woody species belonging to 101 genera and 55 families in the C. lanceolata plantation community, with complex species composition. As a constructive species, C. lanceolata had the highest importance value and niche breadth, and thus was the absolute dominant species in the community. It had a large niche overlap and niche similarity with many other species, among which the highest was observed in Adinandra hainanensis. The average niche overlap and niche similarity of the community were 0.54 and 0.49, respectively. The change trends of those two niche indicators were basically the same, indicating that some species were similar in resource demands. The overall association of main woody species was significantly positive. The χ2 test, association coefficient, Pearson correlation coefficient, and Spearman rank correlation coefficient suggested that the amounts of pairs with positive association were more than that with negative ones. The proportion of significant association species pairs was relatively low, indicating that the community stability was strong, species could coexist stably, and most species did not form close ties. On the whole, C. lanceolata had inhibited the regeneration of original tree species, and A. hainanensis, Garcinia oblongifolia, and Heptapleurum heptaphyllum could be used in natural transformation and restoration of C. lanceolata plantation in the Hainan Tropical Rainforest National Park.


Asunto(s)
Cunninghamia , Ecosistema , Cunninghamia/crecimiento & desarrollo , Cunninghamia/clasificación , China , Bosque Lluvioso , Conservación de los Recursos Naturales , Árboles/crecimiento & desarrollo , Árboles/clasificación , Biodiversidad
6.
Comp Biochem Physiol B Biochem Mol Biol ; 275: 111024, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39173872

RESUMEN

Myostatin (MSTN) plays an important role in muscle development in animals, especially for mammals and fishes. However, little information has been reported on the regulation of MSTN in marine invertebrates, such as bivalves. In the present study, we cloned the MSTN promoter sequence of Yesso scallop Patinopecten yessoensis, identifying 4 transcription start sites, eleven TATA boxes and one E-box. Additionally, transcription factor binding sites, including myocyte enhancer factor 2 (MEF2) and POU homeodomain protein, were identified. The interaction between the MSTN promoter and MEF2 was analyzed to reveal the transcriptional activity of different fragment sizes of promoters through the dual-luciferase reporter assays. The highest transcriptional activity was found in recombinant plasmids with the most MEF2 binding sites, indicating that this transcription factor upregulates MSTN in Yesso scallop. This study provides new insight into the regulation of muscle growth and development in this species.

7.
Nano Lett ; 24(36): 11187-11193, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39141575

RESUMEN

Antiferromagnets (AFMs) are ideal materials to boost neuromorphic computing toward the ultrahigh speed and ultracompact integration regime. However, developing a suitable AFM neuromorphic memory remains an aspirational but challenging goal. In this work, we construct such a memory based on the CoO/Pt heterostructure, in which the collinear insulating AFM CoO shows a strong perpendicular anisotropy facilitating its electrical readout and writing. Utilizing the unique nonlinear response and bipolar fading memory properties of the device, we demonstrate a multidimensional reservoir computing beyond the traditional binary paradigm. These results are expected to pave the way toward next-generation fast and massive neuromorphic computing.

8.
Sci Rep ; 14(1): 18313, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39112496

RESUMEN

Object detector based on fully convolutional network achieves excellent performance. However, existing detection algorithms still face challenges such as low detection accuracy in dense scenes and issues with occlusion of dense targets. To address these two challenges, we propose an Global Remote Feature Modulation End-to-End (GRFME2E) detection algorithm. In the feature extraction phase of our algorithm, we introduces the Concentric Attention Feature Pyramid Network (CAFPN). The CAFPN captures direction-aware and position-sensitive information, as well as global remote dependencies of features in deep layers by combining Coordinate Attention and Multilayer Perceptron. These features are used to modulate the front-end shallow features, enhancing inter-layer feature adjustment to obtain comprehensive and distinctive feature representations.In the detector part, we introduce the Two-Stage Detection Head (TS Head). This head employs the First-One-to-Few (F-O2F) module to detect slightly or unobstructed objects. Additionally, it uses masks to suppress already detected instances, and then feeds them to the Second-One-to-Few (S-O2F) module to identify those that are heavily occluded. The results from both detection stages are merged to produce the final output, ensuring the detection of objects whether they are slightly obscured, unobstructed, or heavily occluded. Experimental results on the pig detection dataset demonstrate that our GRFME2E achieves an accuracy of 98.4%. In addition, more extensive experimental results show that on the CrowdHuman dataset, our GRFME2E achieves 91.8% and outperforms other methods.

9.
Front Surg ; 11: 1387246, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39170098

RESUMEN

Background: Portal vein tumor thrombus (PVTT) is a major risk factor of recurrence of hepatocellular carcinoma (HCC) after hepatectomy. Whether postoperative adjuvant immunotherapy and molecular targeted therapy (I-O and MTT) is effective in reducing the risk of recurrence of HCC with minimal portal invasion after hepatectomy and improving prognosis is unknown. Methods: We collected the data of HCC with Vp1 or Vp2 PVTT patients who underwent hepatectomy at our center between January 2019 and June 2022 from the hospital database. We utilized propensity score matching (PSM) to establish a 1:1 match between the postoperative group treated with I-O and MTT and the postoperative group without I-O and MTT. To compare the recurrence-free survival (RFS) and overall survival (OS) between the two groups, we employed the Kaplan-Meier method. Additionally, we conducted Cox regression analysis to identify the prognostic factors that influence patient prognosis. To account for different high-risk factors, subgroup analyses were carried out. Results: Among the 189 patients included in the study, 42 patients received postoperative adjuvant I-O and MTT. After PSM, the 1, 2-years RFS were 59.2%, 21.3% respectively in the I-O and MTT group and 40.8%, 9.6% respectively in the non-I-O and MTT group. The median RFS was 13.2 months for the I-O and MTT group better than 7.0 months for the non-I-O and MTT group (P = 0.028). 1, 2-years OS were 89.8%, 65.8% respectively in the I-O and MTT group and 42.4%, 27.7% respectively in the non-I-O and MTT group. The median OS was 23.5 months for the I-O and MTT group better than 17.2 months for the non-I-O and MTT group (P = 0.027). Multivariate analysis showed that postoperative adjuvant I-O and MTT was a prognostic protective factor associated with OS and RFS. The most frequent AE observed in this study was pruritus, and rare AEs included decreased platelet, hypothyroidism, proteinuria, myocarditis and hypoadrenocorticism. The incidence of GRADE ≥3 AE with no deaths recorded. Conclusion: The study suggested that postoperative adjuvant I-O and MTT strategy was beneficial to improve the prognosis of HCC patients with PVTT patients, while the therapy was safe and reliable.

10.
Environ Int ; 190: 108890, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39033732

RESUMEN

BACKGROUND: The growing consensus links exposure to fine particulate matter (PM2.5) with an increased risk of respiratory diseases. However, little is known about the additional effects of particulate matter on brainstem function in allergic rhinitis (AR). Furthermore, it is unknown to what extent the PM2.5-induced effects in the brainstem affect the inflammatory response in AR. This study aimed to determine the effects, mechanisms and consequences of brainstem neural activity altered by allergenic stimulation and PM2.5 exposure. METHODS: Using an AR model of ovalbumin (OVA) elicitation and whole-body PM2.5 exposure, the metabolic profile of the brainstem post-allergen stimulation was characterized through in vivo proton magnetic resonance imaging (1H-MRS). Then, the transient receptor potential vanilloid-1 (TRPV1) neuronal expression and sensitivity in the trigeminal nerve in AR were investigated. The link between TRPV1 expression and brainstem differential metabolites was also determined. Finally, we evaluated the mediating effects of brainstem metabolites and the consequences in the brain-spleen axis in the inflammatory response of AR. RESULTS: Exposure to allergens and PM2.5 led to changes in the metabolic profiles of the brainstem, particularly affecting levels of glutamine (Gln) and glutamate (Glu). This exposure also increased the expression and sensitivity of TRPV1+ neurons in the trigeminal nerve, with the levels of TRPV1 expression closely linked to the brainstem metabolism of Glu and Gln. Moreover, allergens increased the activity of p38, while PM2.5 led to the phosphorylation of p38 and ERK, resulting in the upregulation of TRPV1 expression. The brainstem metabolites Glu and Gln were found to partially mediate the impact of TRPV1 on AR inflammation, which was supported by the presence of pro-inflammatory changes in the brain-spleen axis. CONCLUSION: Brainstem metabolites are altered under allergen stimulation and additional PM2.5 exposure in AR via sensitization of the trigeminal nerve, which exacerbates the inflammatory response via the brain-splenic axis.


Asunto(s)
Alérgenos , Tronco Encefálico , Material Particulado , Rinitis Alérgica , Bazo , Canales Catiónicos TRPV , Tronco Encefálico/metabolismo , Rinitis Alérgica/metabolismo , Animales , Alérgenos/efectos adversos , Canales Catiónicos TRPV/metabolismo , Bazo/metabolismo , Masculino , Ovalbúmina , Contaminantes Atmosféricos/efectos adversos , Ratones
11.
Int J Biol Macromol ; 277(Pt 2): 134078, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39038575

RESUMEN

Herbicides are essential for farmers to control weed. However, prolonged use of herbicides has caused the development of herbicide resistance in weeds. Here, the resistant Echinochloa crus-galli (RL5) was obtained by continuous treatment with metamifop for five generations in paddy fields. RL5 plants showed a 13.7-fold higher resistance to metamifop compared to susceptible E. crus-galli (SL5) plants. Pre-treatment with GST inhibitor (NBD-Cl) significantly increased the susceptibility of RL5 plants to metamifop. Faster metamifop metabolism and higher GST activity in RL5 plants than in SL5 plants were also confirmed, highlighting the role of GST in metabolic resistance. RNA-Seq analysis identified EcGSTU23 as a candidate gene, and this gene was up-regulated in RL5 and field-resistant E. crus-galli plants. Furthermore, the EcGSTU23 gene was overexpressed in the transgenic EcGSTU23-Maize, and the EcGSTU23-Maize showed resistance to metamifop. In vitro metabolic studies also revealed that the purified EcGSTU23 displayed catalytic activity in glutathione (GSH) conjugation, and metamifop was rapidly metabolized in the co-incubation system containing EcGSTU23 protein. These results provide direct experimental evidence of EcGSTU23's involvement in the metabolic resistance of E. crus-galli to metamifop. Understanding the resistance mechanism can help in devising effective strategies to combat herbicide resistance and breeding of genetically modified herbicide resistant crops.


Asunto(s)
Echinochloa , Glutatión Transferasa , Resistencia a los Herbicidas , Echinochloa/efectos de los fármacos , Echinochloa/genética , Glutatión Transferasa/genética , Glutatión Transferasa/metabolismo , Resistencia a los Herbicidas/genética , Herbicidas/farmacología , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Plantas Modificadas Genéticamente , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
12.
Nanoscale ; 16(28): 13694-13702, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-38967458

RESUMEN

Asymmetric nickel oxyhydroxide (NiOOH) possesses multi-OH and O active sites on different surfaces, (001) and (001̄), which possibly causes a complicated catalytic process. Density functional theory (DFT) calculations reveal that the unconventional dual-site mechanism (UDSM) of the oxygen evolution reaction (OER) on NiOOH (001) and (001̄) exhibits significantly lower overpotentials of 0.80 and 0.77 V, compared to 1.24 and 1.62 V for the single-site mechanism (SSM), respectively. Through chemical doping or heterojunction modifications, the constructed NiOOH@FeOOH (001̄) heterojunction reduces the thermodynamic overpotential to 0.49 V from original 0.77 V undergoing the UDSM. Although Fe/Co-doping or physical compression yield similar or slightly higher overpotentials and are not conductive to facilitating the OER process by the UDSM, all dual-site paths exhibit obviously lower overpotentials than the SSM for pristine and regulated NiOOH (001) and (001̄) from the whole viewpoint. This work identifies a more reasonable and efficient dual-site OER mechanism, which is expected to help the rational design of highly-efficient electrocatalysts.

13.
Nano Lett ; 24(30): 9186-9194, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39012034

RESUMEN

The interaction between light and moiré superlattices presents a platform for exploring unique light-matter phenomena. Tailoring these optical properties holds immense potential for advancing the utilization of moiré superlattices in photonics, optoelectronics, and valleytronics. However, the control of the optical polarization state in moiré superlattices, particularly in the presence of moiré effects, remains elusive. Here, we unveil the emergence of optical anisotropy in moiré superlattices by constructing twisted WSe2/WSe2/SiP heterostructures. We report a linear polarization degree of ∼70% for moiré excitons, attributed to the spatially nonuniform charge distribution, corroborated by first-principles calculations. Furthermore, we demonstrate the modulation of this linear polarization state via the application of a magnetic field, resulting in polarization angle rotation and a magnetic-field-dependent linear polarization degree, influenced by valley coherence and moiré potential effects. Our findings demonstrate an efficient strategy for tuning the optical polarization state of moiré superlattices using heterointerface engineering.

14.
Molecules ; 29(11)2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38893321

RESUMEN

Owing to the important role of and increasing demand for lithium resources, lithium extraction is crucial. The use of molecular extractants is a promising strategy for selective lithium recovery, in which the interaction between lithium and the designed extractant can be manipulated at the molecular level. Herein, we demonstrate that anion receptors of tripodal hexaureas can selectively extract Li2SO4 solids into water containing DMSO (0.8% water) compared to other alkali metal sulfates. The hexaurea receptor with terminal hexyl chains displays the best Li+ extraction selectivity at 2-fold over Na+ and 12.5-fold over K+. The driving force underpinning selective lithium extraction is due to the combined interactions of Li+-SO42- electrostatics and the ion-dipole interaction of the lithium-receptor (carbonyl groups and N atoms); the latter was found to be cation size dependent, as supported by computational calculations. This work indicates that anion binding receptors could drive selective cation extraction, thus providing new insights into the design of receptors for ion recognition and separation.

15.
Materials (Basel) ; 17(11)2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38893834

RESUMEN

Phosphates play a crucial role in drug design, but their negative charge and high polarity make the transmembrane transport of phosphate species challenging. This leads to poor bioavailability of phosphate drugs. Combretastatin-A4 phosphate (CA4P) is such an anticancer monoester phosphate compound, but its absorption and clinical applicability are greatly limited. Therefore, developing carrier systems to effectively deliver phosphate drugs like CA4P is essential. Anion receptors have been found to facilitate the transmembrane transport of anions through hydrogen bonding. In this study, we developed a tripodal hexaurea anion receptor (L1) capable of binding anionic CA4P through hydrogen bonding, with a binding constant larger than 104 M-1 in a DMSO/water mixed solvent. L1 demonstrated superior binding ability compared to other common anions, and exhibited negligible cell cytotoxicity, making it a promising candidate for future use as a carrier for drug delivery.

16.
Phys Rev E ; 109(5-1): 054113, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38907411

RESUMEN

We discover that quantum dynamical tunneling, occurring between phase space regions in a classically forbidden way, can break conserved quantities. We rigorously prove that a conserved quantity in a class of typical pseudointegrable systems can be broken quantum mechanically. We then numerically compute the uncertainties of this broken conserved quantity, which remain nonzero for up to 10^{5} eigenstates and exhibit universal distributions similar to energy level statistics. Furthermore, all the eigenstates with large uncertainties show the superpositions of regular orbits with different values of the conserved quantity, showing definitive manifestation of dynamical tunneling. A random matrix model is constructed to successfully reproduce the level statistics of pseudointegrable systems.

17.
Nano Lett ; 24(26): 8189-8197, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38904278

RESUMEN

IV-V two-dimensional materials have emerged as key contenders for polarization-sensitive and angle-resolved devices, given their inherent anisotropic physical properties. While these materials exhibit intriguing high-pressure quasi-particle behavior and phase transition, the evolution of quasi-particles and their interactions under external pressure remain elusive. Here, employing a diamond anvil cell and spectroscopic measurements coupled with first-principles calculations, we unveil rarely observed pressure-induced phonon-phonon coupling in layered SiP flakes. This coupling manifests as an anomalous phonon hardening behavior for the A1 mode within a broad wavenumber phonon softening region. Furthermore, we demonstrate the effective tuning of exciton emissions in SiP flakes under pressure, revealing a remarkable 63% enhancement in the degree of polarization (DOP) within the pressure range of 0-3.5 GPa. These findings contribute to our understanding of high-pressure phonon evolution in SiP materials and offer a strategic approach to manipulate the anisotropic performance of in-plane anisotropic 2D materials.

18.
Dalton Trans ; 53(24): 10065-10069, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38847200

RESUMEN

Heteroleptic, bimetallic (Mg/K) cyclopentadienyl complexes (2-4) were synthesized by the reaction of the Mg-Mg-bonded compound [K(THF)3]2[LMg-MgL] (1, L = [(2,6-iPr2C6H3)NC(CH3)]22-) with cyclopentadiene derivatives, 6,6-dimethylfulvene, 6-(dimethylamino)fulvene, or 1,2,3,4-tetramethyl-1,3-cyclopentadiene. The reactions proceed through diverse pathways, including hydrogen abstraction, C-C coupling, and dehydrogenation, depending on the property of the polyene substrate, thus providing an access to alkali/alkaline earth metal cyclopentadienyl complexes.

19.
Angew Chem Int Ed Engl ; 63(33): e202406946, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-38802316

RESUMEN

Control of phosphate capture and release is vital in environmental, biological, and pharmaceutical contexts. However, the binding of trivalent phosphate (PO4 3-) in water is exceptionally difficult due to its high hydration energy. Based on the anion coordination chemistry of phosphate, in this study, four charge-neutral tripodal hexaurea receptors (L1-L4), which were equipped with morpholine and polyethylene glycol terminal groups to enhance their solubility in water, were synthesized to enable the pH-triggered phosphate binding and release in aqueous solutions. Encouragingly, the receptors were found to bind PO4 3- anion in a 1 : 1 ratio via hydrogen bonds in 100 % water solutions, with L1 exhibiting the highest binding constant (1.2×103 M-1). These represent the first neutral anion ligands to bind phosphate in 100 % water and demonstrate the potential for phosphate capture and release in water through pH-triggered mechanisms, mimicking native phosphate binding proteins. Furthermore, L1 can also bind multiple bioavailable phosphate species, which may serve as model systems for probing and modulating phosphate homeostasis in biological and biomedical researches.


Asunto(s)
Aniones , Fosfatos , Agua , Fosfatos/química , Agua/química , Aniones/química , Concentración de Iones de Hidrógeno , Materiales Biomiméticos/química , Materiales Biomiméticos/metabolismo , Enlace de Hidrógeno , Estructura Molecular , Sitios de Unión
20.
BMC Pregnancy Childbirth ; 24(1): 351, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38720272

RESUMEN

BACKGROUND: Plasma microRNAs act as biomarkers for predicting and diagnosing diseases. Reliable non-invasive biomarkers for biochemical pregnancy loss have not been established. We aim to analyze the dynamic microRNA profiles during the peri-implantation period and investigate if plasma microRNAs could be non-invasive biomarkers predicting BPL. METHODS: In this study, we collected plasma samples from patients undergoing embryo transfer (ET) on ET day (ET0), 11 days after ET (ET11), and 14 days after ET (ET14). Patients were divided into the NP (negative pregnancy), BPL (biochemical pregnancy loss), and CP (clinical pregnancy) groups according to serum hCG levels at day11~14 and ultrasound at day28~35 following ET. MicroRNA profiles at different time-points were detected by miRNA-sequencing. We analyzed plasma microRNA signatures for BPL at the peri-implantation stage, we characterized the dynamic microRNA changes during the implantation period, constructed a microRNA co-expression network, and established predictive models for BPL. Finally, the sequencing results were confirmed by Taqman RT-qPCR. RESULTS: BPL patients have distinct plasma microRNA profiles compared to CP patients at multiple time-points during the peri-implantation period. Machine learning models revealed that plasma microRNAs could predict BPL. RT-qPCR confirmed that miR-181a-2-3p, miR-9-5p, miR-150-3p, miR-150-5p, and miR-98-5p, miR-363-3p were significantly differentially expressed between patients with different reproductive outcomes. CONCLUSION: Our study highlights the non-invasive value of plasma microRNAs in predicting BPL.


Asunto(s)
Aborto Espontáneo , Biomarcadores , Transferencia de Embrión , MicroARNs , Humanos , Femenino , Embarazo , MicroARNs/sangre , Adulto , Biomarcadores/sangre , Aborto Espontáneo/sangre , Implantación del Embrión , Aprendizaje Automático
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