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1.
Proc Natl Acad Sci U S A ; 119(8)2022 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35181607

RESUMEN

Interface phonon modes that are generated by several atomic layers at the heterointerface play a major role in the interface thermal conductance for nanoscale high-power devices such as nitride-based high-electron-mobility transistors and light-emitting diodes. Here we measure the local phonon spectra across AlN/Si and AlN/Al interfaces using atomically resolved vibrational electron energy-loss spectroscopy in a scanning transmission electron microscope. At the AlN/Si interface, we observe various interface phonon modes, of which the extended and localized modes act as bridges to connect the bulk AlN modes and bulk Si modes and are expected to boost the phonon transport, thus substantially contributing to interface thermal conductance. In comparison, no such phonon bridge is observed at the AlN/Al interface, for which partially extended modes dominate the interface thermal conductivity. This work provides valuable insights into understanding the interfacial thermal transport in nitride semiconductors and useful guidance for thermal management via interface engineering.

2.
Chem Soc Rev ; 53(7): 3350-3383, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38406832

RESUMEN

Super-resolution imaging has rapidly emerged as an optical microscopy technique, offering advantages of high optical resolution over the past two decades; achieving improved imaging resolution requires significant efforts in developing super-resolution imaging agents characterized by high brightness, high contrast and high sensitivity to fluorescence switching. Apart from technical requirements in optical systems and algorithms, super-resolution imaging relies on fluorescent dyes with special photophysical or photochemical properties. The concept of aggregation-induced emission (AIE) was proposed in 2001, coinciding with unprecedented advancements and innovations in super-resolution imaging technology. AIE probes offer many advantages, including high brightness in the aggregated state, low background signal, a larger Stokes shift, ultra-high photostability, and excellent biocompatibility, making them highly promising for applications in super-resolution imaging. In this review, we summarize the progress in implementation methods and provide insights into the mechanism of AIE-based super-resolution imaging, including fluorescence switching resulting from photochemically-converted aggregation-induced emission, electrostatically controlled aggregation-induced emission and specific binding-regulated aggregation-induced emission. Particularly, the aggregation-induced emission principle has been proposed to achieve spontaneous fluorescence switching, expanding the selection and application scenarios of super-resolution imaging probes. By combining the aggregation-induced emission principle and specific molecular design, we offer some comprehensive insights to facilitate the applications of AIEgens (AIE-active molecules) in super-resolution imaging.

3.
J Am Chem Soc ; 146(33): 22913-22917, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39110062

RESUMEN

The magneto-optical response of chiral materials holds significant potential for applications in physics, chemistry, and biology. However, exploration of the near-infrared (NIR) magneto-optical response remains limited. Herein, we report the synthesis and strong NIR-II magneto-optical activity of three pairs of chiral 3d-4f clusters of R/S-Ln15Cu54 (Ln = Sm, Gd, and Dy). Structural analysis reveals that R/S-Ln15Cu54 features a triangular prism cage with C3 symmetry. Interestingly, magnetic circular dichroism (MCD) spectra exhibit remarkable magneto-optical response in the NIR-II region, driven by the f-f transition. The maximum g-factor of R/S-Sm15Cu54 reaches 5.5 × 10-3 T-1 around 1300-1450 nm, surpassing values associated with DyIII and CuII ions. This remarkable NIR-II magneto-optical activity may be attributed to strong magnetic-dipole-allowed f-f transitions and helix chirality of the structure. This work not only presents the largest Ln-Cu clusters to date but also demonstrate the key role of magnetic-dipole-allowed transitions on magneto-optical activity.

4.
Chembiochem ; : e202400326, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39235968

RESUMEN

Photochromic diarylethene has attracted broad research interest in optical applications owing to its excellent fatigue resistance and unique bistability. Photoswitchable fluorescent diarylethene become a powerful molecular tool for fluorescence imaging recently. Herein, the recent progress on photoswitchable fluorescent diarylethenes in bioimaging is reviewed. We summarize summarized the structures and properties of diarylethene fluorescence probes, and emphatically introduces their applications in bioimaging as well as super-resolution imaging. Additionally, we highlight the current challenges in practical applications and provides the prospects of the future development directions of photoswitchable fluorescent diarylethene in the field of bioimaging.  This comprehensive review aims to stimulate further research into higher performance photoswitchable fluorescent molecules and advance their progress in biological application.

5.
J Org Chem ; 89(16): 11513-11524, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39051980

RESUMEN

N-Acyl/sulfonyl-α-functionalized 1,2,3,4-tetrahydroisoquinolines (THIQs) are significant structural motifs in organic synthesis and drug discovery. However, the one-pot approach enabling direct difunctionalization of THIQs remains challenging. Herein we report a photomediated one-pot three-component strategy to access N-acyl/sulfonyl-α-functionalized THIQs. This method features the use of oxygen (from air) as the green oxidant, high atom and step economy, and decent structural diversity. The synthetic applicability of the method was further demonstrated via the facile construction of valuable bioactive molecules. Mechanistic studies indicated that oxidation with singlet oxygen and the acceptor-less dehydrogenation were involved in the photoredox process.

6.
Inorg Chem ; 63(20): 9204-9211, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38701353

RESUMEN

In this work, a novel organodiphosphate-containing inorganic-organic hybrid polyoxoniobate (PONb) ring {(PO3CH2CH2PO3H)4Nb8O16}4- (Nb8P8) has been achieved by a one-pot hydrothermal method. The ring is constructed from a tetragonal {Nb8O36} motif and four {PO3CH2CH2PO3H} ligands. Interestingly, Nb8P8 can be joined together via K-H2O clusters {K2(H2O)4(OH)2} to form one-dimensional chains {[K2(H2O)4(OH)2]Nb8P8}n and further linked by {Cu(en)2}2+ (en = ethylenediamine) complexes, resulting in a three-dimensional supramolecular framework {[Cu(en)2]2[K2(H2O)4(OH)2]Nb8P8}·3en·H2O (1). 1 exhibits good chemical and thermal stability and has a high water vapor adsorption capacity of ≤224 cm3 g-1 (22.71 mol·mol-1) at 298 K, outperforming most of the known polyoxometalate-based materials. Impedance measurements prove that 1 can transfer protons with moderate conductivity. This study not only contributes to the structural diversity of organodiphosphate-containing PONbs and PONb rings but also provides a reference for the development of PONb-based materials with unique performance.

7.
Int J Colorectal Dis ; 39(1): 142, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39289219

RESUMEN

OBJECTIVE: The aim of this study is to evaluate the significance of combined detection of Septin9 and syndecan-2 (SDC2) methylation markers and serum tumor markers for the early diagnosis of colorectal cancer. METHODS: A total of 116 patients diagnosed with colorectal cancer between December 2022 and February 2024 were designated as the colorectal cancer group. Additionally, 31 patients with colorectal adenoma were assigned to the adenoma group, while 44 individuals undergoing routine physical examinations were included in the control group. Concentrations of Septin9, SDC2, fecal occult blood (FOB), and four tumor markers-carcinoembryonic antigen (CEA), carbohydrate antigen 199 (CA199), carbohydrate antigen 125 (CA125), and carbohydrate antigen 724 (CA724)-were measured. Diagnostic performance was assessed using receiver operating characteristic (ROC) curves for Septin9, SDC2, the four tumor markers, FOB, the combination of Septin9 and SDC2, and the combined use of all seven indicators (CEA, CA19-9, CA125, CA72-4, FOB, Septin9, and SDC2). RESULTS: The colorectal cancer group exhibited the highest positive rates for Septin9, SDC2, the four tumor markers, the combined detection of Septin9 and SDC2, and the combined detection of all seven indicators, compared to both the adenoma and control groups (P < 0.05). The adenoma group also showed higher positive rates than the control group (P < 0.05). For patients with stage I-III colorectal cancer, the positive rates for the combined detection of Septin9 and SDC2 were 81.3%, 78.9%, and 90.2%, respectively, surpassing those for the combined detection of the four tumor markers (43.8%, 55.3%, and 61.0%). Additionally, the positive rates for the two-gene combination in stage III colorectal cancer were higher than those for FOB (P < 0.05). The sensitivity and area under the curve (AUC) for SDC2 were 73.3% and 0.855, respectively, exceeding the sensitivity and AUC for the combined four tumor markers, which were 60.3% and 0.734 (P < 0.05). The combined detection of the two methylated genes demonstrated a sensitivity of 86.2% and an AUC of 0.908, outperforming both FOB and the combined detection of the four tumor markers (P < 0.05). CONCLUSION: The detection of SDC2 exhibits high sensitivity for colorectal cancer, and when combined with Septin9, it significantly enhances the diagnostic accuracy for early-stage colorectal cancer, offering substantial clinical value.


Asunto(s)
Biomarcadores de Tumor , Neoplasias Colorrectales , Detección Precoz del Cáncer , Septinas , Sindecano-2 , Humanos , Septinas/sangre , Septinas/genética , Sindecano-2/sangre , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/diagnóstico , Biomarcadores de Tumor/sangre , Femenino , Masculino , Persona de Mediana Edad , Detección Precoz del Cáncer/métodos , Anciano , Curva ROC , Adulto , Sangre Oculta
8.
Brain Cogn ; 175: 106133, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38241821

RESUMEN

BACKGROUND: Working memory refers to our ability to temporarily store and process information, and it is crucial for efficient cognition and motor control. In the context of badminton matches, athletes need to make quick decisions and reactions in rapidly changing situations. Athletes with strong working memory capacity can better process this information and translate it into actual motor performance. Although previous research has demonstrated that exercise can improve brain function and structure, it remains unclear how the brain functions of athletes engaged in long-term professional training are specifically involved in performing working memory tasks. METHOD: In this study, we assessed behavioral performance and cerebral oxygenation in the prefrontal lobe, using functional near-infrared spectroscopy, with 22 athletes and 30 non-athletes. Each participant was evaluated while performing 1-back, 2-back, and 3-back tasks. The area under the curve (AUC) of HbO (oxyhemoglobin) is used as an indicator of cortical brain oxygenation. RESULTS: The behavioral performance results indicated no difference between badminton athletes and non-athletes in the n-back task. We observed significantly different activation in channels of left FPA, right DLPFC, and left VLPFC when performing 3-back tasks. Brain activation indicated that long-term training in badminton caused a better performance in high-load working memory tasks. CONCLUSIONS: Long-term professional training in badminton primarily activates the left frontal-parietal attention network (left FPA), right dorsolateral prefrontal cortex (right DLPFC), and left ventrolateral prefrontal cortex (left VLPFC) during working memory tasks.


Asunto(s)
Encéfalo , Memoria a Corto Plazo , Humanos , Memoria a Corto Plazo/fisiología , Corteza Prefrontal/fisiología , Cognición/fisiología , Corteza Cerebral
9.
Lipids Health Dis ; 23(1): 83, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38509578

RESUMEN

OBJECTIVE: To enhance the detection, management and monitoring of Chinese children afflicted with sitosterolemia by examining the physical characteristics and genetic makeup of pediatric patients. METHODS: In this group, 26 children were diagnosed with sitosterolemia, 24 of whom underwent genetic analysis. Patient family medical history, physical symptoms, tests for liver function, lipid levels, standard blood tests, phytosterol levels, cardiac/carotid artery ultrasounds, fundus examinations, and treatment were collected. RESULTS: The majority (19, 73.1%) of the 26 patients exhibited xanthomas as the most prevalent manifestation. The second most common symptoms were joint pain (7, 26.9%) and stunted growth (4, 15.4%). Among the 24 (92.3%) patients whose genetics were analyzed, 16 (66.7%) harbored ABCG5 variants (type 2 sitosterolemia), and nearly one-third (8, 33.3%) harbored ABCG8 variants (type 1 sitosterolemia). Additionally, the most common pathogenic ABCG5 variant was c.1166G > A (p.Arg389His), which was found in 10 patients (66.7%). Further analysis did not indicate any significant differences in pathological traits among those carrying ABCG5 and ABCG8 variations (P > 0.05). Interestingly, there was a greater abundance of nonsense variations in ABCG5 than in ABCG8 (P = 0.09), and a greater frequency of splicing variations in ABCG8 than ABCG5 (P = 0.01). Following a change in diet or a combination of ezetimibe, the levels of cholesterol and low-density lipoprotein were markedly decreased compared to the levels reported before treatment. CONCLUSION: Sitosterolemia should be considered for individuals presenting with xanthomas and increased cholesterol levels. Phytosterol testing and genetic analysis are important for early detection. Managing one's diet and taking ezetimibe can well control blood lipids.


Asunto(s)
Hipercolesterolemia , Enfermedades Intestinales , Errores Innatos del Metabolismo Lipídico , Fitosteroles , Fitosteroles/efectos adversos , Xantomatosis , Humanos , Niño , Lipoproteínas/genética , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 5/genética , Fitosteroles/genética , Colesterol , Ezetimiba/uso terapéutico
10.
Mikrochim Acta ; 191(4): 187, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38453742

RESUMEN

Two kinds of carbon dots with the maximum fluorescence peak of 492 nm (named as G-CDs) and 607 nm (named as R-CDs) were synthesized. In the presence of MoO42- ions, the fluorescence of R-CDs at 607 nm can be quenched, which can probably be assigned to their aggregation caused by MoO42-, while that of G-CDs at 492 nm remained unchanged. For the first time, a ratiometric fluorescence probe was developed for MoO42- ions detection. In the range 0.25 ~ 100 µM, the fluorescence ratio (F492/F607) of the probe was linearly related to MoO42- concentration, and the detection limit was 61.5 nM, which fully meets the minimum detection requirements of MoO42- ions in drinking water. On the other hand, when MoO42- was introduced, a significant fading phenomenon of R-CDs can be observed with the naked eye; thereby, the colorimetric method can also be proposed. Based on above, the ratiometric fluorometric/colorimetric dual-mode sensing method was established for MoO42- anion quantification. Compared with the traditional analysis methods, the results obtained by multimodal sensing can be mutually verified, which effectively improves the accuracy and reliability. The dual-mode assay proposed in this work provides an alternative scheme to meet the need of sensing target compounds in complex matrices.

11.
Molecules ; 29(5)2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38474676

RESUMEN

An efficient dearomative (3 + 2) cycloaddition of para-quinamines and 2-nitrobenzofurans has been developed. This reaction proceeds smoothly under mild conditions and affords a series of benzofuro[3,2-b]indol-3-one derivatives in good to excellent yields (up to 98%) with perfect diastereoselectivities (all cases > 20:1 dr). The scale-up synthesis and versatile derivatizations demonstrate the potential synthetic application of the protocol. A plausible reaction mechanism is also proposed to account for the observed reaction process. This work represents the first instance of the N-triggered dearomative (3 + 2) cycloaddition of 2-nitrobenzofurans.

12.
Angew Chem Int Ed Engl ; 63(8): e202316706, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38126129

RESUMEN

Diarylethene molecular photoswitches hold great fascination as optical information materials due to their unique bistability and exceptional reversible photoswitching properties. Conventional diarylethenes, however, rely on UV light for ring-closure reactions, typically with modest yields. For practical application, diarylethenes driven by visible lights are preferred but achieving high ring-closure reaction yield remains a significant challenge. Herein, we synthesized a novel all-visible-light-driven photoswitch, TPAP-DTE, by facilely endcapping the dithienylethene (DTE) core with triphenylamine phenyl (TPAP) groups. Owing to the electron-donating conjugation effect of TPAP, the open-form TPAP-DTE responds strongly to short-wavelength visible lights with considerable photocyclization quantum yields and molar absorption coefficient. Upon 405 nm visible-light irradiation, TPAP-DTE achieves a ring-closure reaction yield exceeding 96.3 % (confirmed by both nuclear magnetic resonance spectroscopy and high-performance liquid chromatography). Its ring-opening reaction yield is 100 % upon irradiation with long-wavelength visible light. TPAP-DTE could be regarded as a bidirectional "quasi"-quantitative conversion molecular switch. Furthermore, TPAP-DTE exhibits robust fatigue resistance over 100 full photoswitching cycles and great anti-aging property under 85 °C and 85 % humidity for at least 1000 h. Consequently, its rewritable QR-code, multilevel data storage, and anti-counterfeiting/encryption applications are successfully demonstrated exclusively using visible lights, positioning TPAP-DTE as a highly promising medium for information recording.

13.
J Am Chem Soc ; 145(42): 23188-23195, 2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37820275

RESUMEN

Inorganic molecular cages are emerging multifunctional molecular-based platforms with the unique merits of rigid skeletons and inherited properties from constituent metal ions. However, the sensitive coordination bonds and vast synthetic space have limited their systematic exploration. Herein, two giant cage-like clusters featuring the organic ligand-directed inorganic skeletons of Ni4[La74Ni104(IDA)96(OH)184(C2O4)12(H2O)76]·(NO3)38·(H2O)120 (La74Ni104, 5 × 5 × 3 - C2O4) and [La84Ni132(IDA)108(OH)168(C2O4)24(NO3)12(H2O)116]·(NO3)72·(H2O)296 (La84Ni132, 5 × 5 × 5 - C2O4) were discovered by a high-throughput synthetic search. With the assistance of machine learning analysis of the experimental data, phase diagrams of the two clusters in a four-parameter synthetic space were depicted. The effect of alkali, oxalate, and other parameters on the formation of clusters and the mechanism regulating the size of two n × m × l clusters were elucidated. This work uses high-throughput synthesis and machine learning methods to improve the efficiency of 3d-4f cluster discovery and finds the highest-nuclearity 3d-4f cluster to date by regulating the size of the n × m × l inorganic cages through oxalate ions, which pushes the synthetic methodology study on elusive inorganic giant cages in a significantly systematic way.

14.
Proc Biol Sci ; 290(1990): 20221658, 2023 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-36629113

RESUMEN

Human-induced biodiversity loss negatively affects ecosystem function, but the interactive effects of biodiversity change across trophic levels remain insufficiently understood. We sampled arboreal spiders and lepidopteran larvae across seasons in 2 years in a subtropical tree diversity experiment, and then disentangled the links between tree diversity and arthropod predator diversity by deconstructing the pathways among multiple components of diversity (taxonomic, phylogenetic and functional) with structural equation models. We found that herbivores were major mediators of plant species richness effects on abundance, species richness, functional and phylogenetic diversity of predators, while phylogenetic, functional and structural diversity of trees were also important mediators of this process. However, the strength and direction differed between functional, structural and phylogenetic diversity effects, indicating different underlying mechanisms for predator community assembly. Abundance and multiple diversity components of predators were consistently affected by tree functional diversity, indicating that the variation in structure and environment caused by plant functional composition might play key roles in predator community assembly. Our study highlights the importance of an integrated approach based on multiple biodiversity components in understanding the consequences of biodiversity loss in multitrophic communities.


Asunto(s)
Artrópodos , Arañas , Animales , Humanos , Ecosistema , Filogenia , Biodiversidad , Plantas
15.
Eur J Nucl Med Mol Imaging ; 50(7): 2081-2099, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36849748

RESUMEN

PURPOSE: Currently, there are multiple active clinical trials involving poly(ADP-ribose) polymerase (PARP) inhibitors in the treatment of glioblastoma. The noninvasive quantification of baseline PARP expression using positron emission tomography (PET) may provide prognostic information and lead to more precise treatment. Due to the lack of brain-penetrant PARP imaging agents, the reliable and accurate in vivo quantification of PARP in the brain remains elusive. Herein, we report the synthesis of a brain-penetrant PARP PET tracer, (R)-2-(2-methyl-1-(methyl-11C)pyrrolidin-2-yl)-1H-benzo[d]imidazole-4-carboxamide ([11C]PyBic), and its preclinical evaluations in a syngeneic RG2 rat glioblastoma model and healthy nonhuman primates. METHODS: We synthesized [11C]PyBic using veliparib as the labeling precursor, performed dynamic PET scans on RG2 tumor-bearing rats and calculated the distribution volume ratio (DVR) using simplified reference region method 2 (SRTM2) with the contralateral nontumor brain region as the reference region. We performed biodistribution studies, western blot, and immunostaining studies to validate the in vivo PET quantification results. We characterized the brain kinetics and binding specificity of [11C]PyBic in nonhuman primates on FOCUS220 scanner and calculated the volume of distribution (VT), nondisplaceable volume of distribution (VND), and nondisplaceable binding potential (BPND) in selected brain regions. RESULTS: [11C]PyBic was synthesized efficiently in one step, with greater than 97% radiochemical and chemical purity and molar activity of 148 ± 85 MBq/nmol (n = 6). [11C]PyBic demonstrated PARP-specific binding in RG2 tumors, with 74% of tracer binding in tumors blocked by preinjected veliparib (i.v., 5 mg/kg). The in vivo PET imaging results were corroborated by ex vivo biodistribution, PARP1 immunohistochemistry and immunoblotting data. Furthermore, brain penetration of [11C]PyBic was confirmed by quantitative monkey brain PET, which showed high specific uptake (BPND > 3) and low nonspecific uptake (VND < 3 mL/cm3) in the monkey brain. CONCLUSION: [11C]PyBic is the first brain-penetrant PARP PET tracer validated in a rat glioblastoma model and healthy nonhuman primates. The brain kinetics of [11C]PyBic are suitable for noninvasive quantification of available PARP binding in the brain, which posits [11C]PyBic to have broad applications in oncology and neuroimaging.


Asunto(s)
Glioblastoma , Ratas , Animales , Glioblastoma/diagnóstico por imagen , Glioblastoma/metabolismo , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/metabolismo , Distribución Tisular , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Tomografía de Emisión de Positrones/métodos , Primates
16.
J Anim Ecol ; 92(2): 442-453, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36507573

RESUMEN

Global biodiversity decline and its cascading effects through trophic interactions pose a severe threat to human society. Establishing the impacts of biodiversity decline requires a more thorough understanding of multi-trophic interactions and, more specifically, the effects that loss of diversity in primary producers has on multi-trophic community assembly. Within a synthetic conceptual framework for multi-trophic beta-diversity, we tested a series of hypotheses on neutral and niche-based bottom-up processes in assembling herbivore and carnivore communities in a subtropical forest using linear models, hieratical variance partitioning based on linear mixed-effects models (LMMs) and simulation. We found that the observed taxonomic, phylogenetic and functional beta-diversity of both herbivorous caterpillars and carnivorous spiders were significantly and positively related to tree dissimilarity. Linear models and variance partitioning for LMMs jointly suggested that as a result of bottom-up effects, producer dissimilarities were predominant in structuring consumer dissimilarity, the strength of which highly depended on the trophic dependencies on producers, the diversity facet examined, and data quality. Importantly, linear models for standardized beta-diversities against producer dissimilarities implied a transition between niche-based processes such as environmental filtering and competitive exclusion, which supports the role of bottom-up effect in determining consumer community assembly. These findings enrich our mechanistic understanding of the 'Diversity Begets Diversity' hypothesis and the complexity of higher-trophic community assembly, which is fundamental for sustainable biodiversity conservation and ecosystem management.


Asunto(s)
Ecosistema , Herbivoria , Humanos , Animales , Filogenia , Biodiversidad , Bosques
17.
Oecologia ; 203(1-2): 205-218, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37831151

RESUMEN

There are many factors known to drive species turnover, although the mechanisms by which these operate are less clear. Based on comprehensive datasets from the largest tree diversity experiment worldwide (BEF-China), we used shared herbivore species (zeta diversity) and multi-site generalized dissimilarity modelling to investigate the patterns and determinants of species turnover of Lepidoptera herbivores among study plots across a gradient in tree species richness. We found that zeta diversity declined sharply with an increasing number of study plots, with complete changes in caterpillar species composition observed even at the fine spatial scale of our study. Plant community characteristics rather than abiotic factors were found to play key roles in driving caterpillar compositional turnover, although these effects varied with an increasing number of study plots considered, due to the varying contributions of rare and common species to compositional turnover. Our study reveals details of the impact of phylogeny- and trait-mediated processes of trees on herbivore compositional turnover, which has implications for forest management and conservation and shows potential avenues for maintenance of heterogeneity in herbivore communities.


Asunto(s)
Herbivoria , Árboles , Biodiversidad , Bosques , Plantas
18.
Surg Endosc ; 37(10): 7698-7708, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37563344

RESUMEN

BACKGROUND: The effects of minimally invasive total mesoesophageal excision (MITME) on the long-term prognosis of locally advanced esophageal squamous cell carcinoma (ESCC) remain unknown. The objective of this study was to compare the static and dynamic failure patterns of MITME and minimally invasive esophagectomy (MIE) for locally advanced ESCC. METHODS: We use propensity score matching (PSM) method to analyze the postoperative failure patterns of the two groups. Cumulative event curves were analyzed for cumulative incidence of failure between different groups, and independent prognostic factors were assessed using time-dependent multivariate analyses. The risk of dynamic failure calculated at 12-month intervals was compared between the two groups using the lifetime table. RESULTS: A total of 366 ESCC patients were studied by 1:1 PSM for T stage and TNM stage (MITME group, n = 183; MIE group, n = 183). In the matched cohort, there was significant differences between the MITME and MIE groups in the failure pattern of regional lymph node recurrence (0.5 vs 3.8%, P = 0.032) and non-tumor death (10.9 vs 31.7%, P < 0.001). The cumulative event curve found that the 5-year cumulative failure rate was lower in the MITME group than in the MIE group (3.3 vs 17.1%, P = 0.026) after 5 years of survival. In addition, multivariate Cox regression analysis showed that MIE was an independent poor prognostic factor for a high cumulative failure rate in locally advanced ESCC patients at 5 years after surgery (HR:4.110; 95% CI 1.047-16.135; P = 0.043). The dynamic risk curve showed that the MITME group had a lower risk of failure within 5 years after surgery than the MIE group. CONCLUSION: Considering that MITME can significantly improve the postoperative failure pattern and the benefit lasts for at least 5 years, it is feasible to use MITME as a treatment for locally advanced ESCC.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Carcinoma de Células Escamosas de Esófago/cirugía , Neoplasias Esofágicas/patología , Estudios de Seguimiento , Estudios de Cohortes , Esofagectomía/métodos , Resultado del Tratamiento , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos
19.
Ecotoxicol Environ Saf ; 252: 114630, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36764072

RESUMEN

Rotenone, a widely used pesticide, causes dopaminergic neurons loss and increase the risk of Parkinson's disease (PD). However, few studies link the role of PARP1 to neuroinflammatory response and autophagy dysfunction in rotenone-induced neurodegeneration. Here, we identified that PARP1 overactivation caused by rotenone led to autophagy dysfunction and NLRP3-mediated inflammation. Further results showed that PARP1 inhibition could reduce NLRP3-mediated inflammation, which was effectively eliminated by TFEB knockdown. Moreover, PARP1 poly(ADP-ribosyl)ated TFEB that reduced autophagy. Of note, PARP1 inhibition could rescue rotenone-induced dopaminergic neurons loss. Overall, our study revealed that PARP1 blocks autophagy through poly (ADP-ribosyl)ating TFEB and inhibited NLRP3 degradation, which suggests that intervention of PARP1-TFEB-NLRP3 signaling can be a new treatment strategy for rotenone-induced neurodegeneration.


Asunto(s)
Enfermedad de Parkinson , Rotenona , Humanos , Rotenona/toxicidad , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/metabolismo , Autofagia , Inflamación , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/farmacología , Poli(ADP-Ribosa) Polimerasa-1/genética
20.
Nano Lett ; 22(1): 476-484, 2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-34978815

RESUMEN

A charge density wave (CDW) is a collective quantum phenomenon in metals and features a wavelike modulation of the conduction electron density. A microscopic understanding and experimental control of this many-body electronic state in atomically thin materials remain hot topics in materials physics. By means of material engineering, we realized a dimensionality and Zr intercalation induced semiconductor-metal phase transition in 1T-ZrX2 (X = Se, Te) ultrathin films, accompanied by a commensurate 2 × 2 CDW order. Furthermore, we observed a CDW energy gap of up to 22 meV around the Fermi level. Fourier-transformed scanning tunneling microscopy and angle-resolved photoemission spectroscopy reveal that 1T-ZrX2 films exhibit the simplest Fermi surface among the known CDW materials in TMDCs, consisting only of a Zr 4d derived elliptical electron conduction band at the corners of the Brillouin zone.

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