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1.
Nature ; 615(7950): 50-55, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36859583

RESUMEN

The newly discovered nickelate superconductors so far only exist in epitaxial thin films synthesized by a topotactic reaction with metal hydrides1. This method changes the nickelates from the perovskite to an infinite-layer structure by deintercalation of apical oxygens1-3. Such a chemical reaction may introduce hydrogen (H), influencing the physical properties of the end materials4-9. Unfortunately, H is insensitive to most characterization techniques and is difficult to detect because of its light weight. Here, in optimally Sr doped Nd0.8Sr0.2NiO2H epitaxial films, secondary-ion mass spectroscopy shows abundant H existing in the form of Nd0.8Sr0.2NiO2Hx (x ≅ 0.2-0.5). Zero resistivity is found within a very narrow H-doping window of 0.22 ≤ x ≤ 0.28, showing unequivocally the critical role of H in superconductivity. Resonant inelastic X-ray scattering demonstrates the existence of itinerant interstitial s (IIS) orbitals originating from apical oxygen deintercalation. Density functional theory calculations show that electronegative H- occupies the apical oxygen sites annihilating IIS orbitals, reducing the IIS-Ni 3d orbital hybridization. This leads the electronic structure of H-doped Nd0.8Sr0.2NiO2Hx to be more two-dimensional-like, which might be relevant for the observed superconductivity. We highlight that H is an important ingredient for superconductivity in epitaxial infinite-layer nickelates.

2.
Nature ; 599(7885): 399-403, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34789901

RESUMEN

The breakdown of translational symmetry at heterointerfaces leads to the emergence of new phonon modes localized at the interface1. These modes have an essential role in thermal and electrical transport properties in devices, especially in miniature ones wherein the interface may dominate the entire response of the device2. Although related theoretical work began decades ago1,3-5, experimental research is totally absent owing to challenges in achieving the combined spatial, momentum and spectral resolutions required to probe localized modes. Here, using the four-dimensional electron energy-loss spectroscopy technique, we directly measure both the local vibrational spectra and the interface phonon dispersion relation for an epitaxial cubic boron nitride/diamond heterointerface. In addition to bulk phonon modes, we observe modes localized at the interface and modes isolated from the interface. These features appear only within approximately one nanometre around the interface. The localized modes observed here are predicted to substantially affect the interface thermal conductance and electron mobility. Our findings provide insights into lattice dynamics at heterointerfaces, and the demonstrated experimental technique should be useful in thermal management, electrical engineering and topological phononics.

3.
Proc Natl Acad Sci U S A ; 120(13): e2213650120, 2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-36940334

RESUMEN

Misfit dislocations at a heteroepitaxial interface produce huge strain and, thus, have a significant impact on the properties of the interface. Here, we use scanning transmission electron microscopy to demonstrate a quantitative unit-cell-by-unit-cell mapping of the lattice parameters and octahedral rotations around misfit dislocations at the BiFeO3/SrRuO3 interface. We find that huge strain field is achieved near dislocations, i.e., above 5% within the first three unit cells of the core, which is typically larger than that achieved from the regular epitaxy thin-film approach, thus significantly altering the magnitude and direction of the local ferroelectric dipole in BiFeO3 and magnetic moments in SrRuO3 near the interface. The strain field and, thus, the structural distortion can be further tuned by the dislocation type. Our atomic-scale study helps us to understand the effects of dislocations in this ferroelectricity/ferromagnetism heterostructure. Such defect engineering allows us to tune the local ferroelectric and ferromagnetic order parameters and the interface electromagnetic coupling, providing new opportunities to design nanosized electronic and spintronic devices.

4.
J Virol ; 98(2): e0195423, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38289102

RESUMEN

During the life cycle of mosquito-borne flaviviruses, substantial subgenomic flaviviral RNA (sfRNA) is produced via incomplete degradation of viral genomic RNA by host XRN1. Zika virus (ZIKV) sfRNA has been detected in mosquito and mammalian somatic cells. Human neural progenitor cells (hNPCs) in the developing brain are the major target cells of ZIKV, and antiviral RNA interference (RNAi) plays a critical role in hNPCs. However, whether ZIKV sfRNA was produced in ZIKV-infected hNPCs as well as its function remains not known. In this study, we demonstrate that abundant sfRNA was produced in ZIKV-infected hNPCs. RNA pulldown and mass spectrum assays showed ZIKV sfRNA interacted with host proteins RHA and PACT, both of which are RNA-induced silencing complex (RISC) components. Functionally, ZIKV sfRNA can antagonize RNAi by outcompeting small interfering RNAs (siRNAs) in binding to RHA and PACT. Furthermore, the 3' stem loop (3'SL) of sfRNA was responsible for RISC components binding and RNAi inhibition, and 3'SL can enhance the replication of a viral suppressor of RNAi (VSR)-deficient virus in a RHA- and PACT-dependent manner. More importantly, the ability of binding to RISC components is conversed among multiple flaviviral 3'SLs. Together, our results identified flavivirus 3'SL as a potent VSR in RNA format, highlighting the complexity in virus-host interaction during flavivirus infection.IMPORTANCEZika virus (ZIKV) infection mainly targets human neural progenitor cells (hNPCs) and induces cell death and dysregulated cell-cycle progression, leading to microcephaly and other central nervous system abnormalities. RNA interference (RNAi) plays critical roles during ZIKV infections in hNPCs, and ZIKV has evolved to encode specific viral proteins to antagonize RNAi. Herein, we first show that abundant sfRNA was produced in ZIKV-infected hNPCs in a similar pattern to that in other cells. Importantly, ZIKV sfRNA acts as a potent viral suppressor of RNAi (VSR) by competing with siRNAs for binding RISC components, RHA and PACT. The 3'SL of sfRNA is responsible for binding RISC components, which is a conserved feature among mosquito-borne flaviviruses. As most known VSRs are viral proteins, our findings highlight the importance of viral non-coding RNAs during the antagonism of host RNAi-based antiviral innate immunity.


Asunto(s)
Infección por el Virus Zika , Virus Zika , Animales , Humanos , Mamíferos/genética , Interferencia de ARN , ARN Interferente Pequeño/genética , ARN Viral/genética , ARN Viral/metabolismo , Complejo Silenciador Inducido por ARN/metabolismo , ARN Subgenómico , Proteínas Virales/metabolismo , Replicación Viral , Virus Zika/fisiología , Infección por el Virus Zika/inmunología , Infección por el Virus Zika/virología
5.
Nano Lett ; 24(11): 3323-3330, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38466652

RESUMEN

Nanoscale defects like grain boundaries (GBs) would introduce local phonon modes and affect the bulk materials' thermal, electrical, optical, and mechanical properties. It is highly desirable to correlate the phonon modes and atomic arrangements for individual defects to precisely understand the structure-property relation. Here we investigated the localized phonon modes of Al2O3 GBs by combination of the vibrational electron energy loss spectroscopy (EELS) in scanning transmission electron microscope and density functional perturbation theory (DFPT). The differences between GB and bulk obtained from the vibrational EELS show that the GB exhibited more active vibration at the energy range of <50 meV and >80 meV, and further DFPT results proved the wide distribution of bond lengths at GB are the main factor for the emergence of local phonon modes. This research provides insights into the phonon-defect relation and would be of importance in the design and application of polycrystalline materials.

6.
Cancer ; 130(16): 2795-2806, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38662418

RESUMEN

BACKGROUND: Prediabetes, which is a precedent of overt diabetes, is a known risk factor for adverse cardiovascular outcomes. Its impact on adverse cardiovascular outcomes in patients with cancer who are prescribed anthracycline-containing chemotherapy (ACT) is uncertain. The objective of this study was to evaluate the association of prediabetes with cardiovascular events in patients with cancer who are prescribed ACT. METHODS: The authors identified patients with cancer who received ACT from 2000 to 2019 from Clinical Data Analysis Reporting System of Hong Kong. Patients were divided into diabetes, prediabetes, and normoglycemia groups based on their baseline glycemic profile. The Primary outcome, a major adverse cardiovascular event (MACE), was the composite event of hospitalization for heart failure and cardiovascular death. RESULTS: Among 12,649 patients at baseline, 3997 had prediabetes, and 5622 had diabetes. Over median follow-up of 8.7 years, the incidence of MACE was 211 (7.0%) in the normoglycemia group, 358 (9.0%) in the prediabetes group, and 728 (12.9%) in the diabetes group. Compared with normoglycemia, prediabetes (adjusted hazard ratio [HR], 1.20; 95% confidence interval [CI], 1.01-1.43) and diabetes (adjusted HR, 1.46; 95% CI, 1.24-1.70) were associated with an increased risk of MACE. In the prediabetes group, 475 patients (18%) progressed to overt diabetes and exhibited a greater risk of MACE (adjusted HR, 1.76; 95% CI, 1.31-2.36) compared with patients who remained prediabetic. CONCLUSIONS: In patients with cancer who received ACT, those who had prediabetes at baseline and those who progressed to diabetes at follow-up had an increased risk of MACE. The optimization of cardiovascular risk factor management, including prediabetes, should be considered in patients with cancer who are treated before and during ACT to reduce cardiovascular risk. PLAIN LANGUAGE SUMMARY: Patients with cancer who have preexisting diabetes have a higher risk of cardiovascular events, and prediabetes is often overlooked. In this study of 12,649 patients with cancer identified in the Clinical Data Analysis Reporting System of Hong Kong who were receiving treatment with anthracycline drugs, prediabetes was correlated with increased deaths from cardiovascular disease and/or hospitalizations for heart failure. Patients who progressed from prediabetes to diabetes within 2 years had an increased risk of combined hospitalization for heart failure and death from cardiovascular disease. These findings indicate the importance of paying greater attention to cardiovascular risk factors, including how prediabetes is managed, in patients who have cancer and are receiving chemotherapy with anthracyclines, emphasizing the need for surveillance, follow-up strategies, and consideration of prediabetes management in cancer care.


Asunto(s)
Antraciclinas , Neoplasias , Estado Prediabético , Humanos , Estado Prediabético/epidemiología , Estado Prediabético/inducido químicamente , Estado Prediabético/complicaciones , Antraciclinas/efectos adversos , Antraciclinas/uso terapéutico , Masculino , Femenino , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Neoplasias/epidemiología , Anciano , Hong Kong/epidemiología , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/inducido químicamente , Adulto , Factores de Riesgo , Diabetes Mellitus/epidemiología , Incidencia
7.
Development ; 148(17)2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34373913

RESUMEN

Neutrophils are the most abundant vertebrate leukocytes and they are essential to host defense. Despite extensive investigation, the molecular network controlling neutrophil differentiation remains incompletely understood. GFI1 is associated with several myeloid disorders, but its role and the role of its co-regulators in granulopoiesis and pathogenesis are far from clear. Here, we demonstrate that zebrafish gfi1aa deficiency induces excessive neutrophil progenitor proliferation, accumulation of immature neutrophils from the embryonic stage, and some phenotypes similar to myelodysplasia syndrome in adulthood. Both genetic and epigenetic analyses demonstrate that immature neutrophil accumulation in gfi1aa-deficient mutants is due to upregulation of cebpa transcription. Increased transcription was associated with Lsd1-altered H3K4 methylation of the cebpa regulatory region. Taken together, our results demonstrate that Gfi1aa, Lsd1 and cebpa form a regulatory network that controls neutrophil development, providing a disease progression-traceable model for myelodysplasia syndrome. Use of this model could provide new insights into the molecular mechanisms underlying GFI1-related myeloid disorders as well as a means by which to develop targeted therapeutic approaches for treatment.


Asunto(s)
Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Proteínas de Unión al ADN/metabolismo , Hematopoyesis/genética , Histona Demetilasas/metabolismo , Neutrófilos/citología , Proteínas de Pez Cebra/metabolismo , Animales , Proteínas Potenciadoras de Unión a CCAAT/genética , Diferenciación Celular , Proliferación Celular , Proteínas de Unión al ADN/deficiencia , Embrión no Mamífero , Epigénesis Genética , Células Precursoras de Granulocitos/citología , Células Precursoras de Granulocitos/metabolismo , Histona Demetilasas/genética , Neutrófilos/metabolismo , Pez Cebra , Proteínas de Pez Cebra/deficiencia , Proteínas de Pez Cebra/genética
8.
Nat Mater ; 22(7): 832-837, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36894772

RESUMEN

The scaling of silicon-based transistors at sub-ten-nanometre technology nodes faces challenges such as interface imperfection and gate current leakage for an ultrathin silicon channel1,2. For next-generation nanoelectronics, high-mobility two-dimensional (2D) layered semiconductors with an atomic thickness and dangling-bond-free surfaces are expected as channel materials to achieve smaller channel sizes, less interfacial scattering and more efficient gate-field penetration1,2. However, further progress towards 2D electronics is hindered by factors such as the lack of a high dielectric constant (κ) dielectric with an atomically flat and dangling-bond-free surface3,4. Here, we report a facile synthesis of a single-crystalline high-κ (κ of roughly 16.5) van der Waals layered dielectric Bi2SeO5. The centimetre-scale single crystal of Bi2SeO5 can be efficiently exfoliated to an atomically flat nanosheet as large as 250 × 200 µm2 and as thin as monolayer. With these Bi2SeO5 nanosheets as dielectric and encapsulation layers, 2D materials such as Bi2O2Se, MoS2 and graphene show improved electronic performances. For example, in 2D Bi2O2Se, the quantum Hall effect is observed and the carrier mobility reaches 470,000 cm2 V-1 s-1 at 1.8 K. Our finding expands the realm of dielectric and opens up a new possibility for lowering the gate voltage and power consumption in 2D electronics and integrated circuits.


Asunto(s)
Grafito , Silicio , Electrónica , Semiconductores
9.
FASEB J ; 37(10): e23188, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37732586

RESUMEN

Diabetic nephropathy (DN) is an important complication of diabetes and the leading cause of end-stage renal disease globally. Renal tubular damage occurs to varying degrees in the early stages of DN prior to glomerular damage. Renalase (RNLS) is an amine oxidase, which is produced and secreted by the renal tubular epithelial cells. RNLS is reportedly closely related to renal tubular injury in acute and chronic kidney diseases. Herein, we aimed to evaluate the changes in tubular RNLS expression in DN and its correlation with DN-associated renal tubular injury. Conditional permanent renal tubular epithelial rat-cell line NRK-52E was transfected with pcDNA3-RNLS plasmid or administered recombinant rat RNLS protein and high glucose (HG) dose. A total of 22 adult Sprague-Dawley rats were randomly divided into the control (CON, n = 10) or diabetic nephrology (DN, n = 12) group. Random blood glucose levels of the rats were measured by sampling of the caudal vein weekly. After 8 weeks, the rat's body weight, 24-h urinary albumin concentration, and right kidney were evaluated. Our study suggested the decreased expression levels of RNLS in renal tissue and renal tubular epithelial cells in DN rats, accompanied by renal tubulointerstitial fibrosis, apoptosis of renal tubular epithelial cells, and activation of the p38MAPK signal pathway. Reversing the low RNLS expression can reduce the level of p38MAPK phosphorylation and delay renal tubular injury. Thus, the reduction of renal tubular RNLS expression in DN mediates tubulointerstitial fibrosis and cell apoptosis via the activation of the p38MAPK signal pathway. RNLS plays a key mediating role in DN-associated tubular injury via p38MAPK, which provides new therapeutic targets and a theoretical basis for early prevention and treatment of DN.


Asunto(s)
Diabetes Mellitus , Nefropatías Diabéticas , Animales , Ratas , Ratas Sprague-Dawley , Riñón , Sistema de Señalización de MAP Quinasas
10.
J Cardiovasc Pharmacol ; 84(3): 370-382, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39027976

RESUMEN

ABSTRACT: Quercetin is known for its antihypertensive effects. However, its role on hypertensive renal injury has not been fully elucidated. In this study, hematoxylin and eosin staining, terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining, and Annexin V staining were used to assess the pathological changes and cell apoptosis in the renal tissues of angiotensin II (Ang II)-infused mice and Ang II-stimulated renal tubular epithelial cell line (NRK-52E). A variety of technologies, including network pharmacology, RNA-sequencing, immunohistochemistry, and Western blotting, were performed to investigate its underlying mechanisms. Network pharmacology analysis identified multiple potential candidate targets (including TP53, Bcl-2, and Bax) and enriched signaling pathways (including apoptosis and p53 signaling pathway). Quercetin treatment significantly alleviated the pathological changes in renal tissues of Ang II-infused mice and reversed 464 differentially expressed transcripts, as well as enriched several signaling pathways, including those related apoptosis and p53 pathway. Furthermore, quercetin treatment significantly inhibited the cell apoptosis in renal tissues of Ang II-infused mice and Ang II-stimulated NRK-52E cells. In addition, quercetin treatment inhibited the upregulation of p53, Bax, cleaved-caspase-9, and cleaved-caspase-3 protein expression and the downregulation of Bcl-2 protein expression in both renal tissue of Ang II-infused mice and Ang II-stimulated NRK-52E cells. Moreover, the molecular docking results indicated a potential binding interaction between quercetin and TP53. Quercetin treatment significantly attenuated hypertensive renal injury and cell apoptosis in renal tissues of Ang II-infused mice and Ang II-stimulated NRK-52E cells and by targeting p53 may be one of the potential underlying mechanisms.


Asunto(s)
Angiotensina II , Antihipertensivos , Apoptosis , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Farmacología en Red , Quercetina , Transducción de Señal , Proteína p53 Supresora de Tumor , Quercetina/farmacología , Animales , Apoptosis/efectos de los fármacos , Línea Celular , Masculino , Transducción de Señal/efectos de los fármacos , Antihipertensivos/farmacología , Ratas , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Redes Reguladoras de Genes/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteínas Reguladoras de la Apoptosis/genética , Riñón/patología , Riñón/efectos de los fármacos , Riñón/metabolismo , RNA-Seq , Regulación de la Expresión Génica/efectos de los fármacos , Ratones , Presión Sanguínea/efectos de los fármacos , Hipertensión Renal/metabolismo , Hipertensión Renal/tratamiento farmacológico , Hipertensión Renal/patología , Nefritis
11.
Circ J ; 88(5): 663-671, 2024 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-38325819

RESUMEN

BACKGROUND: Complications arising from transcatheter closure of perimembranous ventricular septal defects (pmVSD) in children, such as residual shunts and aortic regurgitation (AR), have been observed. However, the associated risk factors remain unclear. This study identified risk factors linked with residual shunts and AR following transcatheter closure of pmVSD in children aged 2-12 years. METHODS AND RESULTS: The medical records of 63 children with pmVSD and a pulmonary-to-systemic blood flow ratio <2.0 who underwent transcatheter closure between 2011 and 2018 were analyzed with a minimum 3-year follow-up. The success rate of transcatheter closure was 98.4%, with no emergency surgery, permanent high-degree atrioventricular block, or mortality. Defects ≥4.5 mm had significantly higher odds of persistent residual shunt (odds ratio [OR] 6.85; P=0.03). The use of an oversize device (≥1.5 mm) showed a trend towards reducing residual shunts (OR 0.23; P=0.06). Age <4 years (OR 27.38; 95% confidence interval [CI] 2.33-321.68) and perimembranous outlet-type VSD (OR 11.94, 95% CI 1.10-129.81) were independent risk factors for AR progression after closure. CONCLUSIONS: Careful attention is crucial for pmVSDs ≥4.5 mm to prevent persistent residual shunts in transcatheter closure. Assessing AR risk, particularly in children aged <4 years, is essential while considering the benefits of pmVSD closure.


Asunto(s)
Cateterismo Cardíaco , Defectos del Tabique Interventricular , Humanos , Defectos del Tabique Interventricular/cirugía , Preescolar , Niño , Factores de Riesgo , Masculino , Femenino , Cateterismo Cardíaco/efectos adversos , Estudios Retrospectivos , Dispositivo Oclusor Septal/efectos adversos , Resultado del Tratamiento , Insuficiencia de la Válvula Aórtica/etiología , Factores de Edad , Factores de Tiempo , Estudios de Seguimiento , Complicaciones Posoperatorias/etiología
12.
Future Oncol ; : 1-19, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39129672

RESUMEN

Aim: Vascular endothelial growth factor receptor inhibitors (VEGFRIs) have been common used for recurrent ovarian cancer (ROC), but insufficient high-level evidence on verifying its efficacy and safety. Methods: Randomized controlled trials (RCTs) were searched under eight electronic databases. Stata 14.0 and Review Manager 5.3 were used for data analysis. Certainty of the evidence was assessed using the GRADE profiler. This systematic review (SR) was registered under INPLASY (INPLASY202120019). Conclusion: Totally 23 RCTs involving 2810 patients were included in this SR. Current evidence revealed that VEGFRIs had better efficacy, survival and quality of life in the treatment of ROC. Though VEGFRIs increase some drug-related adverse events (AEs), all the AEs could be manageable in the clinical practice.


The expression of VEGF/VEGF receptors (VEGFRs) in ovarian cancer (OC) tissue was found to be higher than in benign or normal ovarian tissue. Therefore angiogenesis inhibitors play an essential role in OC treatment. Many anti-angiogenic agents have been developed in recent years. The role of small-molecule inhibitors of VEGFRs for recurrent OC (ROC) has demonstrated significant antitumor efficacy. These drugs include Nintedanib, Axitinib, Pazopanib, Sorafenib, Vandetanib, Sunitinib, Cediranib, Ramucirumab and Apatinib, and more are in the way. However, insufficient high-level evidence from systematic reviews (SRs) focused on VEGFRIs for ROC. Therefore, we performed an SR to investigate the efficacy and safety of VEGFRIs for patients with ROC. This SR was registered under INPLASY (INPLASY202120019). Totally 23 RCTs involving 2810 patients were included in this SR. The results indicate that VEGFRIs have better efficacy and survival in the treatment of ROC. Though VEGFRIs increase some drug-related adverse events, all the adverse events could be manageable in clinical practice.

13.
J Nat Prod ; 87(4): 1103-1115, 2024 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-38600744

RESUMEN

Twelve new alkaloids, scolopenolines A-L (1-7, 9-11, 13, 14), along with six known analogues, were isolated from Scolopendra subspinipes mutilans, identified by analysis of spectroscopic data and quantum chemical and computational methods. Scolopenoline A (1), a unique guanidyl-containing C14 quinoline alkaloid, features a 6/6/5 ring backbone. Scolopenoline B (2) is a novel sulfonyl-containing heterodimer comprising quinoline and tyramine moieties. Scolopenoline G (7) presents a rare C12 quinoline skeleton with a 6/6/5 ring system. Alkaloids 1, 8, 10, and 15-18 display anti-inflammatory activity, while 10 and 16-18 also exhibit anti-renal-fibrosis activity. Drug affinity responsive target stability and RNA-interference assays show that Lamp2 might be a potentially important target protein of 16 for anti-renal-fibrosis activity.


Asunto(s)
Alcaloides , Animales Ponzoñosos , Quilópodos , Animales , Alcaloides/farmacología , Alcaloides/química , Alcaloides/aislamiento & purificación , Estructura Molecular , Artrópodos/química , Fibrosis/tratamiento farmacológico , Riñón/efectos de los fármacos , Quinolinas/farmacología , Quinolinas/química , Antiinflamatorios/farmacología , Antiinflamatorios/química , Humanos
14.
Nature ; 557(7707): 674-678, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29795342

RESUMEN

Protein ubiquitination is a multifaceted post-translational modification that controls almost every process in eukaryotic cells. Recently, the Legionella effector SdeA was reported to mediate a unique phosphoribosyl-linked ubiquitination through successive modifications of the Arg42 of ubiquitin (Ub) by its mono-ADP-ribosyltransferase (mART) and phosphodiesterase (PDE) domains. However, the mechanisms of SdeA-mediated Ub modification and phosphoribosyl-linked ubiquitination remain unknown. Here we report the structures of SdeA in its ligand-free, Ub-bound and Ub-NADH-bound states. The structures reveal that the mART and PDE domains of SdeA form a catalytic domain over its C-terminal region. Upon Ub binding, the canonical ADP-ribosyltransferase toxin turn-turn (ARTT) and phosphate-nicotinamide (PN) loops in the mART domain of SdeA undergo marked conformational changes. The Ub Arg72 might act as a 'probe' that interacts with the mART domain first, and then movements may occur in the side chains of Arg72 and Arg42 during the ADP-ribosylation of Ub. Our study reveals the mechanism of SdeA-mediated Ub modification and provides a framework for further investigations into the phosphoribosyl-linked ubiquitination process.


Asunto(s)
Legionella pneumophila/enzimología , Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo , Ubiquitina/metabolismo , Ubiquitinación , ADP Ribosa Transferasas/química , ADP Ribosa Transferasas/metabolismo , Arginina/metabolismo , Proteínas Bacterianas , Dominio Catalítico , Cristalografía por Rayos X , Modelos Moleculares , Chaperonas Moleculares/metabolismo , NAD/metabolismo , Hidrolasas Diéster Fosfóricas/química , Hidrolasas Diéster Fosfóricas/metabolismo , Procesamiento Proteico-Postraduccional , Especificidad por Sustrato , Ubiquitina/química
15.
Acta Pharmacol Sin ; 45(9): 1821-1831, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38702501

RESUMEN

Enteroendocrine cells (EECs) and vagal afferent neurons constitute functional sensory units of the gut, which have been implicated in bottom-up modulation of brain functions. Sodium oligomannate (GV-971) has been shown to improve cognitive functions in murine models of Alzheimer's disease (AD) and recently approved for the treatment of AD patients in China. In this study, we explored whether activation of the EECs-vagal afferent pathways was involved in the therapeutic effects of GV-971. We found that an enteroendocrine cell line RIN-14B displayed spontaneous calcium oscillations due to TRPA1-mediated calcium entry; perfusion of GV-971 (50, 100 mg/L) concentration-dependently enhanced the calcium oscillations in EECs. In ex vivo murine jejunum preparation, intraluminal infusion of GV-971 (500 mg/L) significantly increased the spontaneous and distension-induced discharge rate of the vagal afferent nerves. In wild-type mice, administration of GV-971 (100 mg· kg-1 ·d-1, i.g. for 7 days) significantly elevated serum serotonin and CCK levels and increased jejunal afferent nerve activity. In 7-month-old APP/PS1 mice, administration of GV-971 for 12 weeks significantly increased jejunal afferent nerve activity and improved the cognitive deficits in behavioral tests. Sweet taste receptor inhibitor Lactisole (0.5 mM) and the TRPA1 channel blocker HC-030031 (10 µM) negated the effects of GV-971 on calcium oscillations in RIN-14B cells as well as on jejunal afferent nerve activity. In APP/PS1 mice, co-administration of Lactisole (30 mg ·kg-1 ·d-1, i.g. for 12 weeks) attenuated the effects of GV-971 on serum serotonin and CCK levels, vagal afferent firing, and cognitive behaviors. We conclude that GV-971 activates sweet taste receptors and TRPA1, either directly or indirectly, to enhance calcium entry in enteroendocrine cells, resulting in increased CCK and 5-HT release and consequent increase of vagal afferent activity. GV-971 might activate the EECs-vagal afferent pathways to modulate cognitive functions.


Asunto(s)
Células Enteroendocrinas , Yeyuno , Canal Catiónico TRPA1 , Nervio Vago , Animales , Masculino , Ratones , Vías Aferentes/efectos de los fármacos , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/genética , Señalización del Calcio/efectos de los fármacos , Línea Celular , Colecistoquinina/metabolismo , Modelos Animales de Enfermedad , Células Enteroendocrinas/metabolismo , Células Enteroendocrinas/efectos de los fármacos , Yeyuno/efectos de los fármacos , Yeyuno/metabolismo , Yeyuno/inervación , Ratones Endogámicos C57BL , Ratones Transgénicos , Presenilina-1/genética , Serotonina/metabolismo , Canal Catiónico TRPA1/metabolismo , Nervio Vago/efectos de los fármacos , Nervio Vago/metabolismo
16.
Environ Res ; 260: 119794, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39142461

RESUMEN

Pharmaceuticals and personal care products (PPCPs) are insufficiently degraded in saline wastewater treatment processes and are found at high concentrations and detection frequencies in aquatic environments. In this study, the wetland plant Thalia dealbata was selected using a screening plant experiment to ensure good salt tolerance and high efficiency in removing PPCPs. An electric integrated vertical-flow constructed wetland (E-VFCW) was developed to improve the removal of PPCPs and reduce the abundance of antibiotic resistance genes (ARGs). The removal efficiency of ofloxacin, enrofloxacin, and diclofenac in the system with anaerobic cathodic and aerobic anodic chambers is higher than that of the control system (41.84 ± 2.88%, 47.29 ± 3.01%, 53.29 ± 2.54%) by approximately 20.31%, 16.04%, and 35.25%. The removal efficiency of ibuprofen in the system with the aerobic anodic and anaerobic cathodic chamber was 28.51% higher than that of the control system (72.41 ± 3.06%) and promotes the reduction of ARGs. Electrical stimulation can increase the activity of plant enzymes, increasing their adaptability to stress caused by PPCPs, and PPCPs are transferred to plants. Species related to PPCPs biodegradation (Geobacter, Lactococcus, Hydrogenophaga, and Nitrospira) were enriched in the anodic and cathodic chambers of the system. This study provides an essential reference for the removal of PPCPs in saline-constructed wetlands.


Asunto(s)
Aguas Residuales , Contaminantes Químicos del Agua , Humedales , Aguas Residuales/microbiología , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Farmacorresistencia Microbiana/genética , Eliminación de Residuos Líquidos/métodos , Preparaciones Farmacéuticas/análisis , Biodegradación Ambiental , Técnicas Electroquímicas/métodos , Antibacterianos
17.
Dig Dis Sci ; 69(7): 2631-2647, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38769225

RESUMEN

Claudin18.2 is a tight junction protein, highly selective, generally expressed only in normal gastric mucosal epithelial cells, which can effectively maintain the polarity of epithelial and endothelial cells, thus effectively regulating the permeability and conductance of the paracellular pathway. Abnormal expression of Claudin18.2 can occur in various primary malignant tumors, especially gastrointestinal tumors, and even in metastatic foci. It regulates its expression by activating the aPKC/MAPK/AP-1 pathway, and therefore, the Claudin18.2 protein is a pan-cancer target expressed in primary and metastatic lesions in human cancer types. Zolbetuximab (IMAB362), an antibody specific for Claudin18.2, has been successfully tested in a phase III clinical trial, and the results of the study showed that combining Zolbetuximab with chemotherapy notably extends patients' survival and is expected to be a potential first-line treatment for patients with Claudin18.2(+)/HER-2(-) gastric cancer. Here, we systematically describe the biological properties and oncogenic effects of Claudin18.2, centering on its clinical-pathological aspects and the progress of drug studies in gastric cancer, which can help to further explore its clinical value.


Asunto(s)
Claudinas , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/patología , Neoplasias Gástricas/metabolismo , Claudinas/metabolismo , Claudinas/genética
18.
Artículo en Inglés | MEDLINE | ID: mdl-39212799

RESUMEN

PURPOSE: Previous studies implied that different types of statins may pose divergent impacts on the risk of glaucoma onset. This study aimed to comprehensively evaluate the effects of various statins on the risk of glaucoma occurrence. METHODS: PubMed, Cochrane CENTRAL, Embase, and Web of Science were searched from February 1994 to February 2024. We included studies that investigated the effects of various types of statins, fibrates, ezetimibe, cholestyramine, niacin, PCSK9 inhibitors, omega-3 fatty acids, and any cholesterol-lowering medications on glaucoma onset or progression. The revised Cochrane risk-of-bias tool for randomized trials (RoB 2.0) and the Risk Of Bias In Non-randomized Studies-of Interventions (ROBINS-1) tool were used to assess the quality of randomized controlled trials (RCTs) and non-RCTs, respectively. The frequentist network meta-analysis framework was utilized to evaluate the comparative effectiveness, with the random effects model applied. RESULTS: This network meta-analysis comprised 12 studies, encompassing 262,217 individuals and including cholesterol-lowering medications such as statins, fibrates, ezetimibe, cholestyramine, niacin, and omega-3 fatty acids. Our findings demonstrate that comparing to the placebo, rosuvastatin (risk ratio [RR], 1.23; 95% confidence interval [CI], 1.03 to 1.46), simvastatin (RR, 1.21; 95% CI, 1.02 to 1.43), and pravastatin (RR, 1.20; 95% CI, 1.01 to 1.43) increased the risk of glaucoma onset with statistical significance. CONCLUSION: Rosuvastatin, simvastatin, and pravastatin were each associated with a significantly increased risk of glaucoma onset. We advise medical practitioners to exercise caution when prescribing these specific statins for patients who are at risk of developing glaucoma. KEY MESSAGES: What is known Previous studies have suggested a link between statins and the risk of developing glaucoma. However, there is still ongoing debate regarding the specific effects of each type of statin on the onset of glaucoma. What is new This network meta-analysis comprehensively evaluated the effects of various statins on the risk of glaucoma onset. Rosuvastatin, simvastatin, and pravastatin were associated with a significantly increased risk of glaucoma onset.

19.
BMC Med Imaging ; 24(1): 240, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39272029

RESUMEN

BACKGROUND: To design a pulmonary ground-glass nodules (GGN) classification method based on computed tomography (CT) radiomics and machine learning for prediction of invasion in early-stage ground-glass opacity (GGO) pulmonary adenocarcinoma. METHODS: This retrospective study included pulmonary GGN patients who were histologically confirmed to have adenocarcinoma in situ (AIS), minimally invasive adenocarcinoma (MIA), or invasive adenocarcinoma cancer (IAC) from 2020 to 2023. CT images of all patients were automatically segmented and 107 radiomic features were obtained for each patient. Classification models were developed using random forest (RF) and cross-validation, including three one-versus-others models and one three-class model. For each model, features were ranked by normalized Gini importance, and a minimal subset was selected with a cumulative importance exceeding 0.9. These selected features were then used to train the final models. The models' performance metrics, including area under the curve (AUC), accuracy, sensitivity, and specificity, were computed. AUC and accuracy were compared to determine the final optimal method. RESULTS: The study comprised 193 patients (mean age 54 ± 11 years, 65 men), including 65 AIS, 54 MIA, and 74 IAC, divided into one training cohort (N = 154) and one test cohort (N = 39). The final three-class RF model outperformed three individual one-versus-others models in distinguishing each class from the other two. For the multiclass classification model, the AUC, accuracy, sensitivity, and specificity were 0.87, 0.79, 0.62, and 0.88 for AIS; 0.90, 0.79, 0.54, and 0.89 for MIA; and 0.87, 0.69, 0.73, and 0.67 for IAC, respectively. CONCLUSIONS: A radiomics-based multiclass RF model could effectively differentiate three types of pulmonary GGN, which enabled early diagnosis of GGO pulmonary adenocarcinoma.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Aprendizaje Automático , Tomografía Computarizada por Rayos X , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Estudios Retrospectivos , Femenino , Masculino , Tomografía Computarizada por Rayos X/métodos , Persona de Mediana Edad , Adenocarcinoma del Pulmón/diagnóstico por imagen , Adenocarcinoma del Pulmón/patología , Anciano , Invasividad Neoplásica/diagnóstico por imagen , Sensibilidad y Especificidad , Radiómica
20.
BMC Public Health ; 24(1): 1591, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38872194

RESUMEN

BACKGROUND: Kawasaki disease (KD) is the most important acquired heart disease in children. This study investigated annual incidence, seasonality, secular trend and the correlation of KD incidence with viral activity in Taiwan. METHODS: Through the national health insurance database, we identified KD during 2001-2020. The viral activity was obtained from nationwide surveillance database. We analyzed KD age-specific annual incidence, secular trends, seasonality and the correlation between KD incidence and common enteric or respiratory viral activity. RESULTS: The KD incidence of subjects younger than 18 years significantly increased from 2001 to 2020 (11.78 and 22.40 per 100,000 person-years, respectively), and substantially decreased with age. Infants younger than 1 year presented the highest KD annual incidence at 105.82 to 164.34 per 100,000 person-years from 2001 to 2020. For all KD patients, the most frequently occurring season was summer followed by autumn. The KD incidence of infants younger than 1 year had significantly positive correlation with enteric (r = 0.14) and respiratory (r = 0.18) viral activity. CONCLUSIONS: This study demonstrates the increasing trend of KD annual incidence and seasonality (more in summer and autumn) in Taiwan. The activity of common respiratory and enteric viruses was significantly correlated with KD incidence in infants.


Asunto(s)
Síndrome Mucocutáneo Linfonodular , Estaciones del Año , Humanos , Síndrome Mucocutáneo Linfonodular/epidemiología , Taiwán/epidemiología , Lactante , Incidencia , Preescolar , Masculino , Femenino , Niño , Adolescente , Recién Nacido , Vigilancia de la Población
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