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1.
Nature ; 595(7866): 239-244, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34234338

RESUMEN

Exotic phenomena can be achieved in quantum materials by confining electronic states into two dimensions. For example, relativistic fermions are realized in a single layer of carbon atoms1, the quantized Hall effect can result from two-dimensional (2D) systems2,3, and the superconducting transition temperature can be considerably increased in a one-atomic-layer material4,5. Ordinarily, a 2D electronic system can be obtained by exfoliating the layered materials, growing monolayer materials on substrates, or establishing interfaces between different materials. Here we use femtosecond infrared laser pulses to invert the periodic lattice distortion sectionally in a three-dimensional (3D) charge density wave material (1T-TiSe2), creating macroscopic domain walls of transient 2D ordered electronic states with unusual properties. The corresponding ultrafast electronic and lattice dynamics are captured by time-resolved and angle-resolved photoemission spectroscopy6 and ultrafast electron diffraction at energies of the order of megaelectronvolts7. Moreover, in the photoinduced 2D domain wall near the surface we identify a phase with enhanced density of states and signatures of potential opening of an energy gap near the Fermi energy. Such optical modulation of atomic motion is an alternative path towards realizing 2D electronic states and will be a useful platform upon which novel phases in quantum materials may be discovered.

2.
Brief Bioinform ; 25(4)2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38864340

RESUMEN

G-protein coupled receptors (GPCRs), crucial in various diseases, are targeted of over 40% of approved drugs. However, the reliable acquisition of experimental GPCRs structures is hindered by their lipid-embedded conformations. Traditional protein-ligand interaction models falter in GPCR-drug interactions, caused by limited and low-quality structures. Generalized models, trained on soluble protein-ligand pairs, are also inadequate. To address these issues, we developed two models, DeepGPCR_BC for binary classification and DeepGPCR_RG for affinity prediction. These models use non-structural GPCR-ligand interaction data, leveraging graph convolutional networks and mol2vec techniques to represent binding pockets and ligands as graphs. This approach significantly speeds up predictions while preserving critical physical-chemical and spatial information. In independent tests, DeepGPCR_BC surpassed Autodock Vina and Schrödinger Dock with an area under the curve of 0.72, accuracy of 0.68 and true positive rate of 0.73, whereas DeepGPCR_RG demonstrated a Pearson correlation of 0.39 and root mean squared error of 1.34. We applied these models to screen drug candidates for GPR35 (Q9HC97), yielding promising results with three (F545-1970, K297-0698, S948-0241) out of eight candidates. Furthermore, we also successfully obtained six active inhibitors for GLP-1R. Our GPCR-specific models pave the way for efficient and accurate large-scale virtual screening, potentially revolutionizing drug discovery in the GPCR field.


Asunto(s)
Descubrimiento de Drogas , Receptores Acoplados a Proteínas G , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Ligandos , Descubrimiento de Drogas/métodos , Humanos , Simulación del Acoplamiento Molecular , Unión Proteica , Sitios de Unión
3.
Nat Chem Biol ; 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39232187

RESUMEN

Protein phosphorylation is a pivotal post-translational modification modulating various cellular processes. In Gram-positive bacteria, the protein arginine kinase McsB, along with its activator McsA, has a key role in labeling misfolded and damaged proteins during stress. However, the activation mechanism of McsB by McsA remains elusive. Here we report the cryo-electron microscopy structure of a tetrameric McsA-McsB complex at 3.41 Å resolution. Biochemical analysis indicates that the homotetrameric assembly is essential for McsB's kinase activity. The conserved C-terminal zinc finger of McsA interacts with an extended loop in McsB, optimally orienting a critical catalytic cysteine residue. In addition, McsA binding decreases the CtsR's affinity for McsB, enhancing McsB's kinase activity and accelerating the turnover rate of CtsR phosphorylation. Furthermore, McsA binding also increases McsB's thermostability, ensuring its activity under heat stress. These findings elucidate the structural basis and activation mechanism of McsB in stress response.

4.
Nat Mater ; 23(9): 1214-1221, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39009656

RESUMEN

A nematic phase breaks the point-group symmetry of the crystal lattice and is known to emerge in correlated materials. Here we report the observation of an intra-unit-cell nematic order and associated Fermi surface deformation in the kagome metal ScV6Sn6. Using scanning tunnelling microscopy and scanning tunnelling spectroscopy, we reveal a stripe-like nematic order breaking the crystal rotational symmetry within the kagome lattice itself. Moreover, we identify a set of Van Hove singularities adhering to the kagome-layer electrons, which appear along one direction of the Brillouin zone and are annihilated along other high-symmetry directions, revealing rotational symmetry breaking. Via detailed spectroscopic maps, we further observe an elliptical deformation of the Fermi surface, which provides direct evidence for an electronically mediated nematic order. Our work not only bridges the gap between electronic nematicity and kagome physics but also sheds light on the potential mechanism for realizing symmetry-broken phases in correlated electron systems.

5.
Methods ; 225: 44-51, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38518843

RESUMEN

The process of virtual screening relies heavily on the databases, but it is disadvantageous to conduct virtual screening based on commercial databases with patent-protected compounds, high compound toxicity and side effects. Therefore, this paper utilizes generative recurrent neural networks (RNN) containing long short-term memory (LSTM) cells to learn the properties of drug compounds in the DrugBank, aiming to obtain a new and virtual screening compounds database with drug-like properties. Ultimately, a compounds database consisting of 26,316 compounds is obtained by this method. To evaluate the potential of this compounds database, a series of tests are performed, including chemical space, ADME properties, compound fragmentation, and synthesizability analysis. As a result, it is proved that the database is equipped with good drug-like properties and a relatively new backbone, its potential in virtual screening is further tested. Finally, a series of seedling compounds with completely new backbones are obtained through docking and binding free energy calculations.


Asunto(s)
Aprendizaje Profundo , Simulación del Acoplamiento Molecular , Simulación del Acoplamiento Molecular/métodos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Evaluación Preclínica de Medicamentos/métodos , Humanos , Bases de Datos Farmacéuticas , Redes Neurales de la Computación , Bases de Datos de Compuestos Químicos
6.
Exp Cell Res ; 442(2): 114231, 2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39222869

RESUMEN

Prostate cancer (PCa) is threatening the health of millions of people, the pathological mechanism of prostate cancer has not been fully elaborated, and needs to be further explored. Here, we found that the expression of DUSP26 is dramatically suppressed, and a positive connection of its expression with PCa prognosis was also observed. In vitro, overexpression of DUSP26 significantly inhibited the proliferative, migrative, and invasive capacities of PC3 cells, DUSP26 silencing presented opposite results. Tumor formation experiments in subcutaneous nude mice demonstrated that DUSP26 overexpression could significantly suppress PC3 growth in vivo. Moreover, the mechanism of DUSP26 gene and PCa was discovered by RNA-Seq analysis. We found that DUSP26 significantly inhibited MAPK signaling pathway activation, and further experiments displayed that DUSP26 could impair TAK1, p38, and JNK phosphorylation. Interestingly, treatment with the TAK1 inhibitor (iTAK1) attenuated the effect of DUSP26 on PC3 cells. Together, these results suggested that DUSP26 may serve as a novel therapeutic target for PC3 cell type PCa, the underlying mechanism may be through TAK1-JNK/p38 signaling.

7.
Nano Lett ; 24(20): 6002-6009, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38739273

RESUMEN

Two-dimensional van der Waals heterostructures (2D-vdWHs) based on transition metal dichalcogenides (TMDs) provide unparalleled control over electronic properties. However, the interlayer coupling is challenged by the interfacial misalignment and defects, which hinders a comprehensive understanding of the intertwined electronic orders, especially superconductivity and charge density wave (CDW). Here, by using pressure to regulate the interlayer coupling of non-centrosymmetric 6R-TaS2 vdWHs, we observe an unprecedented phase diagram in TMDs. This phase diagram encompasses successive suppression of the original CDW states from alternating H-layer and T-layer configurations, the emergence and disappearance of a new CDW-like state, and a double superconducting dome induced by different interlayer coupling effects. These results not only illuminate the crucial role of interlayer coupling in shaping the complex phase diagram of TMD systems but also pave a new avenue for the creation of a novel family of bulk heterostructures with customized 2D properties.

8.
J Cell Mol Med ; 28(4): e18113, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38332530

RESUMEN

The resistance to anoikis plays a critical role in the metastatic progression of various types of malignancies, including gastric cancer (GC). Nevertheless, the precise mechanism behind anoikis resistance is not fully understood. Here, our primary focus was to examine the function and underlying molecular mechanism of Integrin beta-like 1 (ITGBL1) in the modulation of anoikis resistance and metastasis in GC. The findings of our investigation have demonstrated that the overexpression of ITGBL1 significantly augmented the resistance of GC cells to anoikis and promoted their metastatic potential, while knockdown of ITGBL1 had a suppressive effect on both cellular processes in vitro and in vivo. Mechanistically, we proved that ITGBL1 has a role in enhancing the resistance of GC cells to anoikis and promoting metastasis through the AKT/Fibulin-2 (FBLN2) axis. The inhibition of AKT/FBLN2 signalling was able to reverse the impact of ITGBL1 on the resistance of GC cells to anoikis and their metastatic capability. Moreover, the expression levels of ITGBL1 were found to be significantly elevated in the cancerous tissues of patients diagnosed with GC, and there was a strong correlation observed between high expression levels of ITGBL1 and worse prognosis among individuals diagnosed with GC. Significantly, it was revealed that within our cohort of GC patients, individuals exhibiting elevated ITGBL1 expression and diminished FBLN2 expression experienced the worst prognosis. In conclusion, the findings of our study indicate that ITGBL1 may serve as a possible modulator of resistance to anoikis and the metastatic process in GC.


Asunto(s)
Anoicis , Proteínas de Unión al Calcio , Neoplasias Gástricas , Humanos , Anoicis/genética , Neoplasias Gástricas/patología , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas de la Matriz Extracelular , Línea Celular Tumoral , Metástasis de la Neoplasia , Integrina beta1/genética
9.
Clin Infect Dis ; 79(1): 169-176, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-38236137

RESUMEN

BACKGROUND: Most international treatment guidelines recommend rapid initiation of antiretroviral therapy (ART) for people newly diagnosed with human immunodeficiency virus (HIV)-1 infection, but experiences with rapid ART initiation remain limited in China. We aimed to evaluate the efficacy and safety of efavirenz (400 mg) plus lamivudine and tenofovir disoproxil fumarate (EFV + 3TC + TDF) versus coformulated bictegravir, emtricitabine, and tenofovir alafenamide (BIC/FTC/TAF) in rapid ART initiation among men who have sex with men (MSM) who have been diagnosed with HIV. METHODS: This multicenter, open-label, randomized clinical trial enrolled MSM aged ≥18 years to start ART within 14 days of confirmed HIV diagnosis. The participants were randomly assigned in a 1:1 ratio to receive EFV (400 mg) + 3TC + TDF or BIC/FTC/TAF. The primary end point was viral suppression (<50 copies/mL) at 48 weeks per US Food and Drug Administration Snapshot analysis. RESULTS: Between March 2021 and July 2022, 300 participants were enrolled; 154 were assigned to receive EFV + 3TC + TDF (EFV group) and 146 BIC/FTC/TAF (BIC group). At week 48, 118 (79.2%) and 140 (95.9%) participants in the EFV and BIC group, respectively, were retained in care with viral suppression, and 24 (16.1%) and 1 (0.7%) participant in the EFV and BIC group (P < .001), respectively, discontinued treatment because of adverse effects, death, or lost to follow-up. The median increase of CD4 count was 181 and 223 cells/µL (P = .020), respectively, for the EFV and BIC group, at week 48. The overall incidence of adverse effects was significantly higher for the EFV group (65.8% vs 37.7%, P < .001). CONCLUSIONS: BIC/FTC/TAF was more efficacious and safer than EFV (400 mg) + 3TC + TDF for rapid ART initiation among HIV-positive MSM in China.


Asunto(s)
Alquinos , Fármacos Anti-VIH , Benzoxazinas , Ciclopropanos , Emtricitabina , Infecciones por VIH , Homosexualidad Masculina , Lamivudine , Tenofovir , Humanos , Masculino , Infecciones por VIH/tratamiento farmacológico , Adulto , Tenofovir/uso terapéutico , Tenofovir/análogos & derivados , China , Emtricitabina/uso terapéutico , Emtricitabina/administración & dosificación , Ciclopropanos/uso terapéutico , Fármacos Anti-VIH/uso terapéutico , Fármacos Anti-VIH/efectos adversos , Fármacos Anti-VIH/administración & dosificación , Alquinos/uso terapéutico , Lamivudine/uso terapéutico , Lamivudine/administración & dosificación , Lamivudine/efectos adversos , Benzoxazinas/uso terapéutico , Alanina/uso terapéutico , Persona de Mediana Edad , Compuestos Heterocíclicos de 4 o más Anillos/uso terapéutico , Compuestos Heterocíclicos de 4 o más Anillos/efectos adversos , Compuestos Heterocíclicos de 4 o más Anillos/administración & dosificación , Recuento de Linfocito CD4 , Dioxolanos/uso terapéutico , Dioxolanos/administración & dosificación , Compuestos Heterocíclicos con 3 Anillos/uso terapéutico , Compuestos Heterocíclicos con 3 Anillos/efectos adversos , Compuestos Heterocíclicos con 3 Anillos/administración & dosificación , Piperazinas/uso terapéutico , Terapia Antirretroviral Altamente Activa/métodos , Carga Viral , Adulto Joven , Combinación de Medicamentos , VIH-1/efectos de los fármacos , Amidas , Piridonas
10.
BMC Genomics ; 25(1): 864, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39285286

RESUMEN

BACKGROUND: Greater yam is a key staple crop grown in tropical and subtropical regions, while its asexual propagation mode had led to non-flowering mutations. How transposable elements contribute to its genetic variations is rarely analyzed. We used transcriptome and whole genome sequencing data to identify active transposable elements (TEs) and genetic variation caused by these active TEs. Our aim was to shed light on which TEs would lead to its intraspecies variation. RESULTS: Annotation of de novo assembly transcripts indicated that 0.8 - 0.9% of transcripts were TE related, with LTR retrotransposons (LTR-RTs) accounted for 65% TE transcripts. A large portion of these transcripts were non-autonomous TEs, which had incomplete functional domains. The majority of mapped transcripts were distributed in genic deficient regions, with 9% of TEs overlapping with genic regions. Moreover, over 90% TE transcripts exhibited low expression levels and insufficient reads coverage to support full-length structure assembly. Subfamily analysis of Copia and Gypsy, the two LTR-RTs revealed that a small number of subfamilies contained a significantly larger number of members, which play a key role in generating TE transcript. Based on resequencing data, 15,002 L-RT insertion loci were detected for active LTR-RT members. The insertion loci of LTR-RTs were highly divergent among greater yam accessions. CONCLUSIONS: This study showed the ongoing transcription and transpositions of TEs in greater yam, despite low transcription levels and incomplete proteins insufficient for autonomous transposition. While our research did not directly link these TEs to specific yam traits such as tuber yield and propagation mode, it lays a crucial foundation for further research on how these TE insertion polymorphisms (TIPs) might be related to variations in greater yam traits and its tuber propagation mode. Future research may explore the potential roles of TEs in trait variations, such as tuber yield and stress resistance, in greater yam.


Asunto(s)
Elementos Transponibles de ADN , Dioscorea , Dioscorea/genética , Dioscorea/crecimiento & desarrollo , Elementos Transponibles de ADN/genética , Retroelementos , Tubérculos de la Planta/genética , Tubérculos de la Planta/crecimiento & desarrollo , Genoma de Planta , Transcriptoma , Variación Genética , Secuencias Repetidas Terminales/genética
11.
J Am Chem Soc ; 146(18): 12681-12690, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38652868

RESUMEN

Lithium (Li) metal solid-state batteries feature high energy density and improved safety and thus are recognized as promising alternatives to traditional Li-ion batteries. In practice, using Li metal anodes remains challenging because of the lack of a superionic solid electrolyte that has good stability against reduction decomposition at the anode side. Here, we propose a new electrolyte design with an antistructure (compared to conventional inorganic structures) to achieve intrinsic thermodynamic stability with a Li metal anode. Li-rich antifluorite solid electrolytes are designed and synthesized, which give a high ionic conductivity of 2.1 × 10-4 S cm-1 at room temperature with three-dimensional fast Li-ion transport pathways and demonstrate high stability in Li-Li symmetric batteries. Reversible full cells with a Li metal anode and LiCoO2 cathode are also presented, showing the potential of Li-rich antifluorites as Li metal-compatible solid electrolytes for high-energy-density solid-state batteries.

12.
Apoptosis ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38960944

RESUMEN

BACKGROUND: Cetuximab is extensively used in the treatment of metastatic colorectal cancer (mCRC). However, resistance poses a significant challenge to successful therapy. Recently, paraptosis, a non-classical programmed cell death, has garnered increased attention for its potential application value in antitumor treatments. We aimed to identify the essential pathways and signaling molecules involved in paraptosis inhibition and select them as therapeutic targets in cetuximab resistance. Additionally, engineered exosome technology is used as a drug delivery system with both targeted and effector properties. RESULTS: By comparing the differential expression of paraptosis-related genes between drug-resistant colon cancer cells and sensitive cells, it was observed that the paraptosis level induced by cetuximab was significantly downregulated in drug-resistant cells. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis identified the focal adhesion kinase (FAK) signaling pathway as a key pathway involved in the suppression of paraptosis. The biological function of FAK in cetuximab-resistant cells was investigated through cell morphology observation, CCK-8 assay, colony formation assay, RT-qPCR, Western Blot, and loss-of-function experiments. The results showed that the FAK signaling pathway was significantly upregulated in cetuximab-resistant colon cancer cells, and siRNA interference targeting FAK could notably inhibit cell proliferation while upregulating the paraptosis level. Based on this, engineered colon cancer cells targeted and FAK siRNA loaded exosomes (CT-Exo-siFAK1) were constructed. In vitro experiments, CT-Exo-siFAK1 could effectively activate paraptosis and inhibit the proliferation of drug-resistant colon cancer cells. In vivo experiments also confirmed that CT-Exo-siFAK1 significantly suppressed tumor growth and metastasis while upregulating the paraptosis level. CONCLUSION: This study suggests that FAK signaling pathway-mediated inhibition of paraptosis levels is crucial in the sensitivity of cetuximab targeted therapy in colon cancer, and the use of engineered exosomes to deliver FAK siRNA may be an effective strategy to reverse cetuximab resistance.

13.
BMC Med ; 22(1): 181, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38685041

RESUMEN

BACKGROUND: Early pregnancy is a critical window for neural system programming; however, the association of first-trimester fetal size with children's neurodevelopment remains to be assessed. This study aimed to explore the association between first-trimester fetal size and children's neurodevelopment and to examine whether intrauterine accelerated growth could compensate for the detrimental effects of first-trimester restricted growth on childhood neurodevelopment. METHODS: The participants were from a birth cohort enrolled from March 2014 to March 2019 in Wuhan, China. A total of 2058 fetuses with crown to rump length (CRL) (a proxy of first-trimester fetal size) measurements in the first trimester and neurodevelopmental assessment at age 2 years were included. We measured the first-trimester CRL and defined three fetal growth patterns based on the growth rate of estimated fetal weight from mid to late pregnancy. The neurodevelopment was assessed using the Bayley Scales of Infant Development of China Revision at 2 years. RESULTS: Each unit (a Z score) increase of first-trimester CRL was associated with increased scores in mental developmental index (MDI) (adjusted beta estimate = 1.19, (95% CI: 0.42, 1.95), P = 0.03) and psychomotor developmental index (PDI) (adjusted beta estimate = 1.36, (95% CI: 0.46, 2.26), P < 0.01) at age 2 years, respectively. No significant association was observed between fetal growth rate and PDI. For children with restricted first-trimester fetal size (the lowest tertile of first-trimester CRL), those with "intrauterine accelerated growth" pattern (higher growth rates) had significantly higher MDI (adjusted beta estimate = 6.14, (95% CI: 3.80, 8.49), P < 0.001) but indistinguishable PDI compared to those with "intrauterine faltering growth" pattern (lower growth rates). Main limitations of this study included potential misclassification of gestational age due to recall bias of the last menstrual period and residual confounding. CONCLUSIONS: The current study suggests that restricted first-trimester fetal size is associated with mental and psychomotor developmental delay in childhood. However, in children with restricted first-trimester fetal size, intrauterine accelerated growth was associated with improved mental development but had little effect on psychomotor development. Additional studies are needed to validate the results in diverse populations.


Asunto(s)
Desarrollo Infantil , Desarrollo Fetal , Primer Trimestre del Embarazo , Humanos , Femenino , Embarazo , Desarrollo Fetal/fisiología , Preescolar , Desarrollo Infantil/fisiología , China , Masculino , Estudios de Cohortes , Adulto , Largo Cráneo-Cadera
14.
Small ; : e2402749, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39031112

RESUMEN

Transition metal dichalcogenide TiSe2 exhibits a superconducting dome within a low pressure range of 2-4 GPa, which peaks with the maximal transition temperature Tc of ≈1.8 K. Here it is reported that applying high pressure induces a new superconducting state in TiSe2, which starts at ≈16 GPa with a substantially higher Tc that reaches 5.6 K at ≈21.5 GPa with no sign of decline. Combining high-throughput first-principles structure search, X-ray diffraction, and Raman spectroscopy measurements up to 30 GPa, It is found that TiSe2 undergoes a first-order structural transition from the 1T phase under ambient pressure to a new 4O phase under high pressure. Comparative ab initio calculations reveal that while the conventional phonon-mediated pairing mechanism may account for the superconductivity observed in 1T-TiSe2 under low pressure, the electron-phonon coupling of 4O-TiSe2 is too weak to induce a superconducting state whose transition temperature is as high as 5.6 K under high pressure. The new superconducting state found in pressurized TiSe2 requires further study on its underlying mechanism.

15.
Opt Express ; 32(10): 17657-17666, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38858943

RESUMEN

Tin diselenide (SnSe2), a layered transition metal dichalcogenide (TMDC), stands out among other TMDCs for its extraordinary photoactive ability and low thermal conductivity. Consequently, it has stimulated many influential researches on photodetectors, ultrafast pulse shaping, thermoelectric devices, etc. However, the carrier mobility in SnSe2, as determined experimentally, remains limited to tens of cm2V-1s-1. This limitation poses a challenge for achieving high-performance SnSe2-based devices. Theoretical calculations, on the other hand, predict that the carrier mobility in SnSe2 can reach hundreds of cm2V-1s-1, approximately one order of magnitude higher than experimental value. Interestingly, the carrier mobility could be underestimated significantly in long-range transportation measurements due to the presence of defects and boundary scattering effects. To address this discrepancy, we employ optic pump terahertz probe spectroscopy to access the photoinduced dynamical THz photoconductivity of SnSe2. Our findings reveal that the intrinsic carrier mobility in conventional SnSe2 single crystal is remarkably high, reaching 353.2 ± 37.7 cm2V-1s-1, consistent with the theoretical prediction. Additionally, dynamical THz photoconductivity measurements reveal that the SnSe2 crystal containing rich defects efficiently capture photoinduced conduction-band electrons and valence-band holes with time constants of ∼20 and ∼200 ps, respectively. Meanwhile, we observe an impulsively stimulated Raman scattering at 0.60 THz. Our study not only demonstrates ultrafast THz spectroscopy as a reliable method for determining intrinsic carrier mobility and detection of low frequency coherent Raman mode in materials but also provides valuable reference for the future application of high-performance SnSe2-based devices.

16.
Opt Lett ; 49(18): 5131-5134, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39270247

RESUMEN

In this Letter, a novel, to the best of our knowledge, robust interferometry based on orbital angular momentum (OAM) is proposed for an in-plane displacement measurement. A vortex beam (VB) is incident onto a diffraction grating, and the ±1st order diffraction beams with conjugate OAM interfere with each other. By demodulating the petal-like interferogram, the in-plane displacement of the grating can be determined. Theoretically, a 1° rotation of the interferogram corresponds to a displacement of 2.31 nm. Experimental results revealed that the maximum measurement error was less than 3.35%. The proposed measurement system combines the advantages of both OAM interferometry and grating interferometry. It adopts the grating pitch instead of the wavelength as the measurement reference, providing robust immunity to environmental disturbances while maintaining high resolution simultaneously.

17.
Phys Rev Lett ; 132(18): 186001, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38759199

RESUMEN

The kagome materials AV_{3}Sb_{5} (A=K, Rb, Cs) host an intriguing interplay between unconventional superconductivity and charge-density waves. Here, we investigate CsV_{3}Sb_{5} by combining high-resolution thermal-expansion, heat-capacity, and electrical resistance under strain measurements. We directly unveil that the superconducting and charge-ordered states strongly compete, and that this competition is dramatically influenced by tuning the crystallographic c axis. In addition, we report the absence of additional bulk phase transitions within the charge-ordered state, notably associated with rotational symmetry breaking within the kagome planes. This suggests that any breaking of the C_{6} invariance occurs via different stacking of C_{6}-symmetric kagome patterns. Finally, we find that the charge-density-wave phase exhibits an enhanced A_{1g}-symmetric elastoresistance coefficient, whose large increase at low temperature is driven by electronic degrees of freedom.

18.
J Nutr ; 154(1): 224-232, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37984738

RESUMEN

BACKGROUND: Studies have claimed that strontium (Sr) is associated with fetal growth, but the research evidence is insufficient. OBJECTIVES: Our study aimed to evaluate associations of trimester-specific urinary Sr concentrations with fetal growth parameters and birth size indicators. METHODS: In this prospective cohort, 9015 urine samples (first trimester: 3561, 2nd trimester: 2756, 3rd trimester: 2698) from 3810 mothers were measured for urinary Sr levels using inductively coupled plasma mass spectrometry (ICP-MS) and adjusted to urine specific gravity. We calculated standard deviation scores (SD-scores) for ultrasound-measured fetal growth parameters (head circumference, abdominal circumference, femur length, and estimated fetal weight) at 16, 24, 31, and 37 wk of gestation and birth size indicators (birth weight, birth length, and Ponderal index). Generalized linear models and generalized estimating equations models were used. Models were adjusted for potential covariates (gestational age, maternal age, body mass index, parity, passive smoking during pregnancy, education, folic acid supplements use, physical activity, maternal and paternal height, and infant sex). RESULTS: Positive associations of naturally logarithm-transformed Sr concentrations with fetal growth parameters and birth size indicators were observed. With each doubling increase in the urinary ln-Sr level in all 3 trimesters resulting in a percent change in SD-scores fetal growth parameters at 24, 31, and 37 wk of gestation and birth size indicators, 5.09%-8.23% in femur length, 7.57%-11.53% in estimated fetal weight, 6.56%-10.42% in abdominal circumference, 6.25% in head circumference, 5.15%-7.85% in birth weight, and 5.71%-9.39% in birth length, respectively. Most of the above statistical results could only be observed in male fetuses. CONCLUSIONS: Our findings suggest a potential association between Sr concentration and increased fetal growth, but these results and underlying mechanisms need further confirmation and clarification.


Asunto(s)
Desarrollo Fetal , Peso Fetal , Embarazo , Femenino , Humanos , Masculino , Peso al Nacer , Estudios Prospectivos , Trimestres del Embarazo
19.
BMC Cancer ; 24(1): 1120, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39251968

RESUMEN

BACKGROUND: Transcatheter arterial chemoembolization (TACE) combined with targeted therapy and immunotherapy can significantly improve the prognosis of patients with hepatocellular carcinoma (HCC). T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domains (TIGIT) is a novel immunosuppressive molecule. This study aimed to analyze the clinical correlation between TIGIT expression on T cells and patients with HCC. METHODS: Clinical data from 140 patients with HCC were retrospectively collected, and TIGIT expression on T cells was examined in each patient. Patients were subsequently divided into high- and low-expression groups, and their prognosis was analyzed. RESULTS: Patients with a high TIGIT expression on their T cells at baseline had a larger tumor volume, later staging, higher proportion of regulatory T cells, higher blood concentrations of interleukin (IL)-6 and IL-10, and lower interferon-γ concentrations. Following TACE, CD155 concentration decreased; however, TACE did not affect TIGIT expression on T cells. Additionally, among patients receiving TACE combined with apatinib and camrelizumab treatment, patients with a high TIGIT expression on T cells had significantly shorter progression-free survival (PFS) and overall survival times than those of patients in the low-expression group. Patients receiving TACE combined with apatinib and camrelizumab treatment with higher TIGIT expression have shorter PFS time than those receiving TACE combined with apatinib treatment. CONCLUSIONS: Patients with HCC that have a high TIGIT expression on their T cells exhibited poorer baseline characteristics, immunosuppressive status, and prognosis after receiving TACE combined with apatinib and camrelizumab and maybe more suited to receive TACE combined with apatinib treatment instead.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Receptores Inmunológicos , Humanos , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/metabolismo , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/mortalidad , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Masculino , Femenino , Pronóstico , Receptores Inmunológicos/metabolismo , Persona de Mediana Edad , Estudios Retrospectivos , Quimioembolización Terapéutica/métodos , Anciano , Linfocitos T/inmunología , Linfocitos T/metabolismo , Adulto , Receptores Virales/metabolismo
20.
Reprod Biomed Online ; 48(2): 103330, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38163419

RESUMEN

RESEARCH QUESTION: Is there a protective effect of the humanin derivative [Gly14]-humanin (HNG) on a D-gal-induced mouse model of primary ovarian insufficiency (POI), and what is the underlying mechanism? DESIGN: D-gal (200 mg/kg/day) was injected subcutaneously for 6 weeks to induce the mouse POI model. Mice treated with HNG were injected intraperitoneally with different concentrations for 6 weeks. Ovarian morphology, function, levels of sex hormones and states of oxidative stress in the ovary and body were evaluated. RESULTS: Compared with the D-gal group, 10 mg/kg HNG improved the abnormal ovarian morphology and oestrous cycle (P = 0.0036), increased the number of ovarian follicles (P = 0.0016) and litters (P = 0.0127), and increased the levels of oestrogen (P = 0.0043) and AMH (P = 0.0147). Antioxidant indicators in the ovaries and serum of mice, including total antioxidant capacity (P = 0.0004 and P = 0.0032, respectively), catalase (P = 0.0173 and P = 0.0103, respectively) and glutathione (both P < 0.0001) were significantly increased. The oxidation indicator malondialdehyde decreased significantly (all P < 0.01). Apoptosis of ovarian granulosa cells was significantly reduced (P = 0.0140) as was the expression of senescence-related proteins p53, p21 and p16 (all P < 0.01). The level of autophagy in ovarian tissue of mice treated with high increased (significantly increased LC3 protein [P < 0.0001] and significantly reduced p62 protein [P = 0.0007]). CONCLUSIONS: HNG inhibited D-gal-induced oxidative stress, apoptosis and ovarian damage, promoting ovarian autophagy. HNG may be a potential prophylactic agent against POI.


Asunto(s)
Péptidos y Proteínas de Señalización Intracelular , Insuficiencia Ovárica Primaria , Humanos , Femenino , Ratones , Animales , Insuficiencia Ovárica Primaria/inducido químicamente , Insuficiencia Ovárica Primaria/prevención & control , Galactosa/efectos adversos , Antioxidantes/farmacología
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