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1.
Am J Hum Genet ; 110(4): 606-624, 2023 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-36868238

RESUMEN

Epigenetic reprogramming plays a critical role in chondrocyte senescence during osteoarthritis (OA) pathology, but the underlying molecular mechanisms remain to be elucidated. Here, using large-scale individual datasets and genetically engineered (Col2a1-CreERT2;Eldrflox/flox and Col2a1-CreERT2;ROSA26-LSL-Eldr+/+ knockin) mouse models, we show that a novel transcript of long noncoding RNA ELDR is essential for the development of chondrocyte senescence. ELDR is highly expressed in chondrocytes and cartilage tissues of OA. Mechanistically, exon 4 of ELDR physically mediates a complex consisting of hnRNPL and KAT6A to regulate histone modifications of the promoter region of IHH, thereby activating hedgehog signaling and promoting chondrocyte senescence. Therapeutically, GapmeR-mediated silencing of ELDR in the OA model substantially attenuates chondrocyte senescence and cartilage degradation. Clinically, ELDR knockdown in cartilage explants from OA-affected individuals decreased the expression of senescence markers and catabolic mediators. Taken together, these findings uncover an lncRNA-dependent epigenetic driver in chondrocyte senescence, highlighting that ELDR could be a promising therapeutic avenue for OA.


Asunto(s)
Cartílago Articular , Osteoartritis , ARN Largo no Codificante , Ratones , Animales , Condrocitos/metabolismo , Condrocitos/patología , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Cromatina/metabolismo , Cartílago Articular/metabolismo , Cartílago Articular/patología , Proteínas Hedgehog/metabolismo , Osteoartritis/genética , Osteoartritis/metabolismo , Osteoartritis/patología
2.
PLoS Pathog ; 20(6): e1012271, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38829910

RESUMEN

Proper transcription regulation by key transcription factors, such as IRF3, is critical for anti-viral defense. Dynamics of enhancer activity play important roles in many biological processes, and epigenomic analysis is used to determine the involved enhancers and transcription factors. To determine new transcription factors in anti-DNA-virus response, we have performed H3K27ac ChIP-Seq and identified three transcription factors, NR2F6, MEF2D and MAFF, in promoting HSV-1 replication. NR2F6 promotes HSV-1 replication and gene expression in vitro and in vivo, but not dependent on cGAS/STING pathway. NR2F6 binds to the promoter of MAP3K5 and activates AP-1/c-Jun pathway, which is critical for DNA virus replication. On the other hand, NR2F6 is transcriptionally repressed by c-Jun and forms a negative feedback loop. Meanwhile, cGAS/STING innate immunity signaling represses NR2F6 through STAT3. Taken together, we have identified new transcription factors and revealed the underlying mechanisms involved in the network between DNA viruses and host cells.


Asunto(s)
Herpesvirus Humano 1 , Inmunidad Innata , Humanos , Animales , Herpesvirus Humano 1/inmunología , Ratones , Replicación Viral , Herpes Simple/inmunología , Herpes Simple/virología , Herpes Simple/metabolismo , Transducción de Señal , Células HEK293 , Proteínas Represoras
3.
J Am Chem Soc ; 146(13): 9272-9284, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38517743

RESUMEN

Metal halide perovskites (MHPs) have garnered significant attention due to their distinctive optical and electronic properties, coupled with excellent processability. However, the thermal characteristics of these materials are often overlooked, which can be harnessed to cater to diverse application scenarios. We showcase the efficacy of lowering the congruent melting temperature (Tm) of layered 2D MHPs by employing a strategy that involves the modification of flexible alkylammonium through N-methylation and I-substitution. Structural-property analysis reveals that the N-methylation and I-substitution play pivotal roles in reducing hydrogen bond interactions between the organic components and inorganic parts, lowering the rotational symmetry number of the cation and restricting the residual motion of the cations. Additional I···I interactions enhance intermolecular interactions and lead to improved molten stability, as evidenced by a higher viscosity. The 2D MHPs discussed in this study exhibit low Tm and wide melt-processable windows, e.g., (DMIPA)2PbI4 showcasing a low Tm of 98 °C and large melt-processable window of 145 °C. The efficacy of the strategy was further validated when applied to bromine-substituted 2D MHPs. Lowering the Tm and enhancing the molten stability of the MHPs hold great promise for various applications, including glass formation, preparation of high-quality films for photodetection, and fabrication of flexible devices.

4.
J Am Chem Soc ; 146(29): 20391-20400, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38987861

RESUMEN

Inspired by enzymatic catalysis, it is crucial to construct hydrogen-bonding-rich microenvironment around catalytic sites; unfortunately, its precise construction and understanding how the distance between such microenvironment and catalytic sites affects the catalysis remain significantly challenging. In this work, a series of metal-organic framework (MOF)-based single-atom Ru1 catalysts, namely, Ru1/UiO-67-X (X = -H, -m-(NH2)2, -o-(NH2)2), have been synthesized, where the distance between the hydrogen-bonding microenvironment and Ru1 sites is modulated by altering the location of amino groups. The -NH2 group can form hydrogen bonds with H2O, constituting a unique microenvironment that causes an increased water concentration around the Ru1 sites. Remarkably, Ru1/UiO-67-o-(NH2)2 displays a superior photocatalytic hydrogen production rate, ∼4.6 and ∼146.6 times of Ru1/UiO-67-m-(NH2)2 and Ru1/UiO-67, respectively. Both experimental and computational results suggest that the close proximity of amino groups to the Ru1 sites in Ru1/UiO-67-o-(NH2)2 improves charge transfer and H2O dissociation, accounting for the promoted photocatalytic hydrogen production.

5.
J Am Chem Soc ; 146(9): 6336-6344, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38381858

RESUMEN

Actuating materials convert different forms of energy into mechanical responses. To satisfy various application scenarios, they are desired to have rich categories, novel functionalities, clear structure-property relationships, fast responses, and, in particular, giant and reversible shape changes. Herein, we report a phase transition-driven ferroelectric crystal, (rac-3-HOPD)PbI3 (3-HOPD = 3-hydroxypiperidine cation), showing intriguingly large and anisotropic room-temperature actuating behaviors. The crystal consists of rigid one-dimensional [PbI3] anionic chains running along the a-axis and discrete disk-like cations loosely wrapping around the chains, leaving room for anisotropic shape changes in both the b- and c-axes. The shape change is switched by a ferroelectric phase transition occurring at around room temperature (294 K), driven by the exceptionally synergistic order-disorder and displacive phase transition. The rotation of the cations exerts internal pressure on the stacking structure to trigger an exceptionally large displacement of the inorganic chains, corresponding to a crystal lattice transformation with length changes of +24.6% and -17.5% along the b- and c-axis, respectively. Single crystal-based prototype devices of circuit switches and elevators have been fabricated by exploiting the unconventional negative temperature-dependent actuating behaviors. This work provides a new model for the development of multifunctional mechanically responsive materials.

6.
Eur J Immunol ; 53(3): e2250122, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36597350

RESUMEN

Autoimmune demyelinating diseases can be induced by an immune response against myelin peptides; however, the exact mechanism underlying the development of such diseases remains unclear. In experimental autoimmune encephalomyelitis, we found that the clearance of exogenous myelin antigen at the peak of the primary immune response is key to the pathogenesis of the disease. The generation of effector T cells requires continuous antigen stimulation, whereas redundant antigen traps and exhausts effector T cells in the periphery, which induces resistance to the disease. Moreover, insufficient antigenic stimulation fails to induce disease efficiently owing to insufficient numbers of effector T cells. When myelin antigen is entirely cleared, the number of effector T cells reaches a peak, which facilitates infiltration of more effector T cells into the central nervous system. The peripheral antigen clearance initiates the first wave of effector T cell entry into the central nervous system and induces chronic inflammation. The inflamed central nervous system recruits the second wave of effector T cells that worsen inflammation, resulting in loss of self-tolerance. These findings provide new insights into the mechanism underlying the development of autoimmune demyelinating diseases, which may potentially impact future treatments.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Animales , Linfocitos T , Sistema Nervioso Central/patología , Inflamación , Inmunidad
7.
Mol Carcinog ; 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39056517

RESUMEN

Many studies have shown that tumor cells that survive radiotherapy are more likely to metastasize, but the underlying mechanism remains unclear. Here we aimed to identify epithelial-mesenchymal transition (EMT)-related key genes, which associated with prognosis and radiosensitivity in rectal cancer. First, we obtained differentially expressed genes by analyzing the RNA expression profiles of rectal cancer retrieved from The Cancer Genome Atlas database, EMT-related genes, and radiotherapy-related databases, respectively. Then, Lasso and Cox regression analyses were used to establish an EMT-related prognosis model (EMTPM) based on the identified independent protective factor Fibulin5 (FBLN5) and independent risk gene EHMT2. The high-EMTPM group exhibited significantly poorer prognosis. Then, we evaluated the signature in an external clinical validation cohort. Through in vivo experiments, we further demonstrated that EMTPM effectively distinguishes radioresistant from radiosensitive patients with rectal cancer. Moreover, individuals in the high-EMTPM group showed increased expression of immune checkpoints compared to their counterparts. Finally, pan-cancer analysis of the EMTPM model also indicated its potential for predicting the prognosis of lung squamous cell carcinoma and breast cancer patients undergoing radiotherapy. In summary, we established a novel predictive model for rectal cancer prognosis and radioresistance based on FBLN5 and EHMT2 expressions, and suggested that immune microenvironment may be involved in the process of radioresistance. This predictive model could be used to select management strategies for rectal cancer.

8.
Am J Pathol ; 193(8): 1059-1071, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37164274

RESUMEN

Unexplained recurrent spontaneous abortion (URSA) has been associated with the dysfunction of trophoblasts and decidual macrophages. Current evidence suggests that profilin1 (PFN1) plays an important role in many biological processes. However, little is known about whether PFN1 is related to URSA. Herein, the location of PFN1 was detected by immunohistochemistry, and the level of PFN1 was detected by quantitative real-time PCR, Western blot analysis, and immunohistochemistry. The proliferation of trophoblasts was detected by CCK8 and 5-ethynyl-2'-deoxyuridine assays, and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assays were used to detect apoptosis of trophoblasts. The migration and invasion ability of trophoblasts was assessed by using the wound-healing test and transwell test. Polarization of macrophages was detected in macrophages cultured in trophoblast conditioned medium. PFN1 expression was observed in cytotrophoblasts, syncytiotrophoblasts, and extravillous trophoblasts and was decreased in the villous tissue of patients with URSA. The migration and invasion ability and cell viability of trophoblastic cell lines that underwent PFN1 knockdown significantly decreased, and apoptosis increased. Opposite findings were observed after the overexpression of PFN1 in trophoblastic cells. In addition, PFN1 could regulate trophoblast function through phosphatidylinositol 3-kinase/AKT signal transduction rather than mitogen-activated protein kinase signaling pathways. Finally, knockdown of PFN1 in trophoblasts promoted tumor necrosis factor-α secretion to induce macrophage polarization to M1 phenotype, mediated by the NF-κB signaling pathway. These findings indicate that PFN1 has a broad therapeutic potential for patients with URSA.


Asunto(s)
Aborto Espontáneo , Trofoblastos , Embarazo , Humanos , Femenino , Trofoblastos/metabolismo , Transducción de Señal/fisiología , FN-kappa B/metabolismo , Sistema de Señalización de MAP Quinasas , Aborto Espontáneo/metabolismo , Diferenciación Celular , Movimiento Celular , Proliferación Celular , Profilinas/genética , Profilinas/metabolismo
9.
Osteoarthritis Cartilage ; 32(1): 66-81, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37802465

RESUMEN

OBJECTIVE: This study aimed to explore the specific function of M2 macrophages in intervertebral disc degeneration (IDD). METHODS: Intervertebral disc (IVD) samples from normal (n = 4) and IDD (n = 6) patients were collected, and the expression of M2-polarized macrophage marker, CD206, was investigated using immunohistochemical staining. Nucleus pulposus cells (NPCs) in a TNF-α environment were obtained, and a mouse caudal IVD puncture model was established. Mice with Rheb deletions, specifically in the myeloid lineage, were generated and subjected to surgery-induced IDD. IDD-induced damage and cell apoptosis were measured using histological scoring, X-ray imaging, immunohistochemical staining, and TdT-mediated dUTP nick end labeling (TUNEL) assay. Finally, mice and NPCs were treated with R-spondin-2 (Rspo2) or anti-Rspo2 to investigate the role of Rspo2 in IDD. RESULTS: Accumulation of CD206 in human and mouse IDD tissues was detected. Rheb deletion in the myeloid lineage (RheBcKO) increased the number of CD206+ M2-like macrophages (mean difference 18.6% [15.7-21.6%], P < 0.001), decreased cell apoptosis (mean difference -15.6% [-8.9 to 22.2%], P = 0.001) and attenuated the IDD process in the mouse IDD model. NPCs treated with Rspo2 displayed increased extracellular matrix catabolism and apoptosis; co-culture with a conditioned medium derived from RheBcKO mice inhibited these changes. Anti-Rspo2 treatment in the mouse caudal IVD puncture model exerted protective effects against IDD. CONCLUSIONS: Promoting CD206+ M2-like macrophages could reduce Rspo2 secretion, thereby alleviating experimental IDD. Rheb deletion may help M2-polarized macrophages accumulate and attenuate experimental IDD partially by inhibiting Rspo2 production. Hence, M2-polarized macrophages and Rspo2 may serve as therapeutic targets for IDD.


Asunto(s)
Degeneración del Disco Intervertebral , Disco Intervertebral , Núcleo Pulposo , Humanos , Ratones , Animales , Degeneración del Disco Intervertebral/patología , Disco Intervertebral/metabolismo , Núcleo Pulposo/metabolismo , Apoptosis , Modelos Animales de Enfermedad , Macrófagos/metabolismo
10.
Histopathology ; 84(4): 601-613, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38032062

RESUMEN

BACKGROUND AND AIMS: ChatGPT is a powerful artificial intelligence (AI) chatbot developed by the OpenAI research laboratory which is capable of analysing human input and generating human-like responses. Early research into the potential application of ChatGPT in healthcare has focused mainly on clinical and administrative functions. The diagnostic ability and utility of ChatGPT in histopathology is not well defined. We benchmarked the performance of ChatGPT against pathologists in diagnostic histopathology, and evaluated the collaborative potential between pathologists and ChatGPT to deliver more accurate diagnoses. METHODS AND RESULTS: In Part 1 of the study, pathologists and ChatGPT were subjected to a series of questions encompassing common diagnostic conundrums in histopathology. For Part 2, pathologists reviewed a series of challenging virtual slides and provided their diagnoses before and after consultation with ChatGPT. We found that ChatGPT performed worse than pathologists in reaching the correct diagnosis. Consultation with ChatGPT provided limited help and information generated from ChatGPT is dependent on the prompts provided by the pathologists and is not always correct. Finally, we surveyed pathologists who rated the diagnostic accuracy of ChatGPT poorly, but found it useful as an advanced search engine. CONCLUSIONS: The use of ChatGPT4 as a diagnostic tool in histopathology is limited by its inherent shortcomings. Judicious evaluation of the information and histopathology diagnosis generated from ChatGPT4 is essential and cannot replace the acuity and judgement of a pathologist. However, future advances in generative AI may expand its role in the field of histopathology.


Asunto(s)
Inteligencia Artificial , Patólogos , Humanos , Biopsia , Derivación y Consulta , Programas Informáticos
11.
Chemistry ; 30(42): e202401395, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38802980

RESUMEN

Phase transitions in molecular solids involve synergistic changes in chemical and electronic structures, leading to diversification in physical and chemical properties. Despite the pivotal role of hydrogen bonds (H-bonds) in many phase-transition materials, it is rare and challenging to chemically regulate the dynamics and to elucidate the structure-property relationship. Here, four high-spin CoII compounds were isolated and systematically investigated by modifying the ligand terminal groups (X=S, Se) and substituents (Y=Cl, Br). S-Cl and Se-Br undergo a reversible structural phase transition near room temperature, triggering the rotation of 15-crown-5 guests and the swing between syn- and anti-conformation of NCX- ligands, accompanied by switchable magnetism. Conversely, S-Br and Se-Cl retain stability in ordered and disordered phases, respectively. H-bonds geometric analysis and ab initio calculations reveal that the electronegativity of X and Y affects the strength of NY-ap-H⋅⋅⋅X interactions. Entropy-driven structural phase transitions occur when the H-bond strength is appropriate; otherwise, the phase stays unchanged if it is too strong or weak. This work highlights a phase transition driven by H-bond strength complementarity - pairing strong acceptor with weak donor and vice versa, which offers a straightforward and effective approach for designing phase-transition molecular solids from a chemical perspective.

12.
J Magn Reson Imaging ; 59(2): 639-647, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37276070

RESUMEN

BACKGROUND: Assessing the glymphatic function using diffusion tensor image analysis along the perivascular space (DTI-ALPS) may be helpful for mild traumatic brain injury (mTBI) management. PURPOSE: To assess glymphatic function using DTI-ALPS and its associations with global white matter damage and cognitive impairment in mTBI. STUDY TYPE: Prospective. POPULATION: Thirty-four controls (44.1% female, mean age 49.2 years) and 58 mTBI subjects (43.1% female, mean age 48.7 years), including uncomplicated mTBI (N = 32) and complicated mTBI (N = 26). FIELD STRENGTH/SEQUENCE: 3-T, single-shot echo-planar imaging sequence. ASSESSMENT: Magnetic resonance imaging (MRI) was done within 1 month since injury. DTI-ALPS was performed to assess glymphatic function, and peak width of skeletonized mean diffusivity (PSMD) was used to assess global white matter damage. Cognitive tests included Auditory Verbal Learning Test and Digit Span Test (forward and backward). STATISTICAL TESTS: Neuroimaging findings comparisons were done between mTBI and control groups. Partial correlation and multivariable linear regression assessed the associations between DTI-ALPS, PSMD, and cognitive impairment. Mediation effects of PSMD on the relationship between DTI-ALPS and cognitive impairment were explored. P-value <0.05 was considered statistically significant, except for cognitive correlational analyses with a Bonferroni-corrected P-value set at 0.05/3 ≈ 0.017. RESULTS: mTBI showed lower DTI-ALPS and higher PSMD, especially in complicated mTBI. DTI-ALPS was significantly correlated with verbal memory (r = 0.566), attention abilities (r = 0.792), executive function (r = 0.618), and PSMD (r = -0.533). DTI-ALPS was associated with verbal memory (ß = 8.77, 95% confidence interval [CI] 5.00, 12.54), attention abilities (ß = 5.67, 95% CI 4.56, 6.97), executive function (ß = 2.34, 95% CI 1.49, 3.20), and PSMD (ß = -0.79, 95% CI -1.15, -0.43). PSMD mediated 46.29%, 20.46%, and 24.36% of the effects for the relationship between DTI-ALPS and verbal memory, attention abilities, and executive function. DATA CONCLUSION: Glymphatic function may be impaired in mTBI reflected by DTI-ALPS. Glymphatic dysfunction may cause cognitive impairment related to global white matter damage after mTBI. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Conmoción Encefálica , Disfunción Cognitiva , Sistema Glinfático , Sustancia Blanca , Femenino , Humanos , Persona de Mediana Edad , Masculino , Conmoción Encefálica/complicaciones , Conmoción Encefálica/diagnóstico por imagen , Estudios Prospectivos , Sustancia Blanca/diagnóstico por imagen , Imagen por Resonancia Magnética , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/etiología
13.
Neuroendocrinology ; 114(8): 786-798, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38815558

RESUMEN

INTRODUCTION: Dimenhydrinate and scopolamine are frequently used drugs, but they cause drowsiness and performance decrement. Therefore, it is crucial to find peripheral targets and develop new drugs without central side effects. This study aimed to investigate the anti-motion sickness action and inner ear-related mechanisms of atrial natriuretic peptide (ANP). METHODS: Endolymph volume in the inner ear was measured with magnetic resonance imaging and expression of AQP2 and p-AQP2 was detected with Western blot analysis and immunofluorescence method. RESULTS: Both rotational stimulus and intraperitoneal arginine vasopressin (AVP) injection induced conditioned taste aversion (CTA) to 0.15% sodium saccharin solution and an increase in the endolymph volume of the inner ear. However, intraperitoneal injection of ANP effectively alleviated the CTA behaviour and reduced the increase in the endolymph volume after rotational stimulus. Intratympanic injection of ANP also inhibited rotational stimulus-induced CTA behaviour, but anantin peptide, an inhibitor of ANP receptor A (NPR-A), blocked this inhibitory effect of ANP. Both rotational stimulus and intraperitoneal AVP injection increased the expression of AQP2 and p-AQP2 in the inner ear of rats, but these increases were blunted by ANP injection. In in vitro experiments, ANP addition decreased AVP-induced increases in the expression and phosphorylation of AQP2 in cultured endolymphatic sac epithelial cells. CONCLUSION: Therefore, the present study suggests that ANP could alleviate motion sickness through regulating endolymph volume of the inner ear increased by AVP, and this action of ANP is potentially mediated by activating NPR-A and antagonising the increasing effect of AVP on AQP2 expression and phosphorylation.


Asunto(s)
Arginina Vasopresina , Factor Natriurético Atrial , Endolinfa , Mareo por Movimiento , Animales , Factor Natriurético Atrial/farmacología , Factor Natriurético Atrial/metabolismo , Factor Natriurético Atrial/administración & dosificación , Arginina Vasopresina/farmacología , Arginina Vasopresina/administración & dosificación , Arginina Vasopresina/metabolismo , Mareo por Movimiento/tratamiento farmacológico , Masculino , Endolinfa/efectos de los fármacos , Endolinfa/metabolismo , Oído Interno/efectos de los fármacos , Ratas Sprague-Dawley , Acuaporina 2/metabolismo , Ratas
14.
Inorg Chem ; 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39313952

RESUMEN

Chirality transfer refers to the process in which chiral cations compel the crystallization of the inorganic component into the Sohncke group. Enhancing the chirality of the inorganic component in chiral organic-inorganic hybrid metal halides (OIHMHs) through chirality transfer, aimed at improving chiroptical and spintronic properties, remains challenging due to the complexity of the underlying mechanism. To investigate this, we propose a novel concept─chirality transfer coefficient─as a means of quantifying the strength of chirality transfer in OIHMHs. A comparative study of OIHMHs with varying dimensionality, metal ions, and chiral centers was conducted to elucidate this mechanism. By analyzing factors such as hydrogen bonding, the number of chiral centers, dimensionality, helical geometry, and structural distortions, we found that chirality transfer is influenced by a combination of structural dimensions and the number of chiral centers. Importantly, our findings reveal that 0D, and 1D OIHMHs, particularly 1D with a zigzag chain configuration, exhibit stronger chirality transfer than their 2D counterparts. Moreover, in 2D OIHMHs, a reduction in the number of chiral centers enhances chirality transfer. However, no direct correlation was observed between chirality transfer and spin splitting. These insights contribute to a more comprehensive understanding of chirality transfer mechanisms and provide a strategic approach for enhancing the chirality transfer and associated physical properties in OIHMHs.

15.
Inorg Chem ; 63(34): 15964-15972, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39148298

RESUMEN

Polyoxometalates (POMs) with various coordination fashions are versatile ligands for constructing single-ion magnets (SIMs), but enforcing POM-SIMs with a specific geometry remains a synthetic challenge. Herein, we synthesized a POM-cocrystallized DyIII-SIM [Dy(OPPh3)4(H2O)3][PW12O40]·4EtOH (1Dy) and a POM-ligated DyIII-SIM [{Dy(OPPh3)3(H2O)3}{PW12O40}]·Ph3PO·H2O (2Dy) with pentagonal bipyramidal local coordination geometry. Magnetic measurements indicate that 1Dy displays field-induced single-molecule magnet (SMM) behavior and the relaxation is dominated by under-barrier processes. 2Dy exhibits spin-lattice relaxation at a broader temperature region with a reversal barrier over 300 K. Magneto-structural analysis reveals that the enhancement of SMM behavior originated from the equatorial replacement of Ph3PO by POM, which strengthens the axial anisotropy in 2Dy. Luminescent experiments indicate that the characteristic DyIII emissions of 1Dy are covered up by the strong π-π* emission of Ph3PO at low-temperature regions. As for 2Dy, partial DyIII emission persists thanks to the antenna effect between DyIII and POM.

16.
BMC Public Health ; 24(1): 2639, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39333980

RESUMEN

OBJECTIVES: This study aimed to quantify the global cardiovascular disease (CVD) burden attributable to diet low in fiber among adults aged 60 years and older using data from the Global Burden of Disease (GBD) Study 2019. METHODS: We extracted data on CVD mortality, disability-adjusted life-years (DALYs), and risk-factor exposures from the GBD 2019 study for people aged 60 and older. Age-period-cohort models were used to estimate the overall annual percentage change in mortality and DALY rate (net drift, % per year), mortality and DALY rate for each age group from 1990 to 2019 (local drift, % per year), longitudinal age-specific rate corrected for period bias (age effect), and mortality and Daly rate for each age group from 1990 to 2019 (local drift, % per year). And period/cohort relative risk (period/cohort effect). RESULTS: From 1990 to 2019, global age-standardized cardiovascular disease (CVD) mortality rates attributable to low dietary fiber intake decreased by 2.37% per year, while disability-adjusted life years (DALYs) fell by 2.48% annually. Decreases were observed across all sociodemographic index regions, with fastest declines in high and high-middle SDI areas. CVD mortality and DALY rates attributable to low fiber increased exponentially with age, peaking at 85-89 years, and were higher in men than women. Regarding period effects, mortality and DALY rates declined since 2000, reaching nadirs in 2015-2019. For birth cohort patterns, risks attributable to low fiber intake peaked among early 1900s births and subsequently fell, with more pronounced reductions over time in women. CONCLUSIONS: Low dietary fiber intake is a leading contributor to the global cardiovascular disease burden, accounting for substantial mortality and disability specifically among older adults over recent decades.


Asunto(s)
Enfermedades Cardiovasculares , Fibras de la Dieta , Carga Global de Enfermedades , Humanos , Enfermedades Cardiovasculares/mortalidad , Enfermedades Cardiovasculares/epidemiología , Anciano , Masculino , Femenino , Persona de Mediana Edad , Anciano de 80 o más Años , Estudios de Cohortes , Años de Vida Ajustados por Discapacidad , Factores de Riesgo , Salud Global/estadística & datos numéricos , Dieta/estadística & datos numéricos
17.
Proc Natl Acad Sci U S A ; 118(21)2021 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-34001600

RESUMEN

G-quadruplexes (G4s) formed by guanine-rich nucleic acids play a role in essential biological processes such as transcription and replication. Besides the >1.5 million putative G-4-forming sequences (PQSs), the human genome features >640 million single-nucleotide variations (SNVs), the most common type of genetic variation among people or populations. An SNV may alter a G4 structure when it falls within a PQS motif. To date, genome-wide PQS-SNV interactions and their impact have not been investigated. Herein, we present a study on the PQS-SNV interactions and the impact they can bring to G4 structures and, subsequently, gene expressions. Based on build 154 of the Single Nucleotide Polymorphism Database (dbSNP), we identified 5 million gains/losses or structural conversions of G4s that can be caused by the SNVs. Of these G4 variations (G4Vs), 3.4 million are within genes, resulting in an average load of >120 G4Vs per gene, preferentially enriched near the transcription start site. Moreover, >80% of the G4Vs overlap with transcription factor-binding sites and >14% with enhancers, giving an average load of 3 and 7.5 for the two regulatory elements, respectively. Our experiments show that such G4Vs can significantly influence the expression of their host genes. These results reveal genome-wide G4Vs and their impact on gene activity, emphasizing an understanding of genetic variation, from a structural perspective, of their physiological function and pathological implications. The G4Vs may also provide a unique category of drug targets for individualized therapeutics, health risk assessment, and drug development.


Asunto(s)
Proteínas de Unión al ADN/ultraestructura , G-Cuádruplex , Genoma Humano/genética , Conformación de Ácido Nucleico , Proteínas de Unión al ADN/genética , Regulación de la Expresión Génica/genética , Humanos , Polimorfismo de Nucleótido Simple/genética , Regiones Promotoras Genéticas/genética , Unión Proteica/genética , Secuencias Reguladoras de Ácidos Nucleicos/genética , Sitio de Iniciación de la Transcripción , Activación Transcripcional/genética
18.
Angew Chem Int Ed Engl ; 63(39): e202410097, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-38953455

RESUMEN

While supported metal nanoparticles (NPs) have shown significant promise in heterogeneous catalysis, precise control over their interaction with the support, which profoundly impacts their catalytic performance, remains a significant challenge. In this study, Pt NPs are incorporated into thioether-functionalized covalent organic frameworks (denoted COF-Sx), enabling precise control over the size and electronic state of Pt NPs by adjusting the thioether density dangling on the COF pore walls. Notably, the resulting Pt@COF-Sx demonstrate exceptional selectivity (> 99 %) in catalytic hydrogenation of p-chloronitrobenzene to p-chloroaniline, in sharp contrast to the poor selectivity of Pt NPs embedded in thioether-free COFs. Furthermore, the conversion over Pt@COF-Sx exhibits a volcano-type curve as the thioether density increases, due to the corresponding change of accessible Pt sites. This work provides an effective approach to regulating the catalysis of metal NPs via their microenvironment modulation, with the aid of rational design and precise tailoring of support structure.

19.
Angew Chem Int Ed Engl ; : e202412643, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39101718

RESUMEN

While metal nanoparticles (NPs) have demonstrated their great potential in catalysis, introducing chiral microenvironment around metal NPs to achieve efficient conversion and high enantioselectivity remains a long-standing challenge. In this work, tiny Rh NPs, modified by chiral diene ligands (Lx) bearing diverse functional groups, are incorporated into a covalent organic framework (COF) for the asymmetric 1,4-addition reactions between arylboronic acids and nitroalkenes. Though Rh NPs hosted in the COF are inactive, decorating Rh NPs with Lx creates the active Rh-Lx interface and induces high activity. Moreover, chiral microenvironment modulation around Rh NPs by altering the groups on chiral diene ligands greatly optimizes the enantioselectivity (up to 95.6% ee). Mechanistic investigations indicate that the formation of hydrogen-bonding interaction between Lx and nitroalkenes plays critical roles in the resulting enantioselectivity. This work highlights the significance of chiral microenvironment modulation around metal NPs by chiral ligand decoration for heterogeneous asymmetric catalysis.

20.
Angew Chem Int Ed Engl ; 63(27): e202401448, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38530747

RESUMEN

Photogenerated radicals are an indispensable member of the state-of-the-art photochromic material family, as they can effectively modulate the photoluminescence and photothermal conversion performance of radical-induced photochromic complexes. Herein, two novel radical-induced photochromic metal-organic frameworks (MOFs), [Ag(TEPE)](AC) ⋅ 7/4H2O ⋅ 5/4EtOH (1) and [Ag(TEPE)](NC) ⋅ 3H2O ⋅ EtOH (2), are reported. Distinctly different topological networks can be obtained by judiciously introducing alternative π-conjugated anionic guests, including a new topological structure (named as sfm) first reported in this work, describing as 4,4,4,4-c net. EPR data and UV-Vis spectra prove the radical-induced photochromic mechanism. Dynamic photochromism exhibits tunability in a wide CIE color space, with a linear segment from yellow to red for 1, while a curved coordinate line for 2, resulting in colorful emission from blue to orange. Moreover, photogenerated TEPE* radicals effectively activate the near-infrared (NIR) photothermal conversion effect of MOFs. Under 1 W cm-2 808 nm laser irradiation, the surface temperatures of photoproducts 1* and 2* can reach ~160 °C and ~120 °C, respectively, with competitive NIR photothermal conversion efficiencies η=51.8 % (1*) and 36.2 % (2*). This work develops a feasible electrostatic compensation strategy to accurately introduce photoactive anionic guests into MOFs to construct multifunctional radical-induced photothermal conversion materials with tunable photoluminescence behavior.

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