Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.082
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
Nature ; 632(8024): 287-293, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39020170

RESUMEN

Compressing the optical field to the atomic scale opens up possibilities for directly observing individual molecules, offering innovative imaging and research tools for both physical and life sciences. However, the diffraction limit imposes a fundamental constraint on how much the optical field can be compressed, based on the achievable photon momentum1,2. In contrast to dielectric structures, plasmonics offer superior field confinement by coupling the light field with the oscillations of free electrons in metals3-6. Nevertheless, plasmonics suffer from inherent ohmic loss, leading to heat generation, increased power consumption and limitations on the coherence time of plasmonic devices7,8. Here we propose and demonstrate singular dielectric nanolasers showing a mode volume that breaks the optical diffraction limit. Derived from Maxwell's equations, we discover that the electric-field singularity sustained in a dielectric bowtie nanoantenna originates from divergence of momentum. The singular dielectric nanolaser is constructed by integrating a dielectric bowtie nanoantenna into the centre of a twisted lattice nanocavity. The synergistic integration surpasses the diffraction limit, enabling the singular dielectric nanolaser to achieve an ultrasmall mode volume of about 0.0005 λ3 (λ, free-space wavelength), along with an exceptionally small feature size at the 1-nanometre scale. To fabricate the required dielectric bowtie nanoantenna with a single-nanometre gap, we develop a two-step process involving etching and atomic deposition. Our research showcases the ability to achieve atomic-scale field localization in laser devices, paving the way for ultra-precise measurements, super-resolution imaging, ultra-efficient computing and communication, and the exploration of light-matter interactions within the realm of extreme optical field localization.

2.
Nature ; 624(7991): 282-288, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38092911

RESUMEN

Miniaturized lasers play a central role in the infrastructure of modern information society. The breakthrough in laser miniaturization beyond the wavelength scale has opened up new opportunities for a wide range of applications1-4, as well as for investigating light-matter interactions in extreme-optical-field localization and lasing-mode engineering5-19. An ultimate objective of microscale laser research is to develop reconfigurable coherent nanolaser arrays that can simultaneously enhance information capacity and functionality. However, the absence of a suitable physical mechanism for reconfiguring nanolaser cavities hinders the demonstration of nanolasers in either a single cavity or a fixed array. Here we propose and demonstrate moiré nanolaser arrays based on optical flatbands in twisted photonic graphene lattices, in which coherent nanolasing is realized from a single nanocavity to reconfigurable arrays of nanocavities. We observe synchronized nanolaser arrays exhibiting high spatial and spectral coherence, across a range of distinct patterns, including P, K and U shapes and the Chinese characters '' and '' ('China' in Chinese). Moreover, we obtain nanolaser arrays that emit with spatially varying relative phases, allowing us to manipulate emission directions. Our work lays the foundation for the development of reconfigurable active devices that have potential applications in communication, LiDAR (light detection and ranging), optical computing and imaging.

3.
Nature ; 593(7859): 418-423, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33727703

RESUMEN

The COVID-19 pandemic is the third outbreak this century of a zoonotic disease caused by a coronavirus, following the emergence of severe acute respiratory syndrome (SARS) in 20031 and Middle East respiratory syndrome (MERS) in 20122. Treatment options for coronaviruses are limited. Here we show that clofazimine-an anti-leprosy drug with a favourable safety profile3-possesses inhibitory activity against several coronaviruses, and can antagonize the replication of SARS-CoV-2 and MERS-CoV in a range of in vitro systems. We found that this molecule, which has been approved by the US Food and Drug Administration, inhibits cell fusion mediated by the viral spike glycoprotein, as well as activity of the viral helicase. Prophylactic or therapeutic administration of clofazimine in a hamster model of SARS-CoV-2 pathogenesis led to reduced viral loads in the lung and viral shedding in faeces, and also alleviated the inflammation associated with viral infection. Combinations of clofazimine and remdesivir exhibited antiviral synergy in vitro and in vivo, and restricted viral shedding from the upper respiratory tract. Clofazimine, which is orally bioavailable and comparatively cheap to manufacture, is an attractive clinical candidate for the treatment of outpatients and-when combined with remdesivir-in therapy for hospitalized patients with COVID-19, particularly in contexts in which costs are an important factor or specialized medical facilities are limited. Our data provide evidence that clofazimine may have a role in the control of the current pandemic of COVID-19 and-possibly more importantly-in dealing with coronavirus diseases that may emerge in the future.


Asunto(s)
Antivirales/farmacología , Clofazimina/farmacología , Coronavirus/clasificación , Coronavirus/efectos de los fármacos , SARS-CoV-2/efectos de los fármacos , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/farmacología , Adenosina Monofosfato/uso terapéutico , Alanina/análogos & derivados , Alanina/farmacología , Alanina/uso terapéutico , Animales , Antiinflamatorios/farmacocinética , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Antivirales/farmacocinética , Antivirales/uso terapéutico , Disponibilidad Biológica , Fusión Celular , Línea Celular , Clofazimina/farmacocinética , Clofazimina/uso terapéutico , Coronavirus/crecimiento & desarrollo , Coronavirus/patogenicidad , Cricetinae , ADN Helicasas/antagonistas & inhibidores , Sinergismo Farmacológico , Femenino , Humanos , Estadios del Ciclo de Vida/efectos de los fármacos , Masculino , Mesocricetus , Profilaxis Pre-Exposición , SARS-CoV-2/crecimiento & desarrollo , Especificidad de la Especie , Glicoproteína de la Espiga del Coronavirus/antagonistas & inhibidores , Transcripción Genética/efectos de los fármacos , Transcripción Genética/genética
4.
Proc Natl Acad Sci U S A ; 120(1): e2209990120, 2023 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-36577069

RESUMEN

Microglia play a critical role in the clearance of myelin debris, thereby ensuring functional recovery from neural injury. Here, using mouse model of demyelination following two-point LPC injection, we show that the microglial autophagic-lysosomal pathway becomes overactivated in response to severe demyelination, leading to lipid droplet accumulation and a dysfunctional and pro-inflammatory microglial state, and finally failed myelin debris clearance and spatial learning deficits. Data from genetic approaches and pharmacological modulations, via microglial Atg5 deficient mice and intraventricular BAF A1 administration, respectively, demonstrate that staged suppression of excessive autophagic-lysosomal activation in microglia, but not sustained inhibition, results in better myelin debris degradation and exerts protective effects against demyelination. Combined multi-omics results in vitro further showed that enhanced lipid metabolism, especially the activation of the linoleic acid pathway, underlies this protective effect. Supplementation with conjugated linoleic acid (CLA), both in vivo and in vitro, could mimic these effects, including attenuating inflammation and restoring microglial pro-regenerative properties, finally resulting in better recovery from demyelination injuries and improved spatial learning function, by activating the peroxisome proliferator-activated receptor (PPAR-γ) pathway. Therefore, we propose that pharmacological inhibition targeting microglial autophagic-lysosomal overactivation or supplementation with CLA could represent a potential therapeutic strategy in demyelinated disorders.


Asunto(s)
Enfermedades Desmielinizantes , Microglía , Ratones , Animales , Microglía/metabolismo , Ácido Linoleico/metabolismo , Autofagia , Enfermedades Desmielinizantes/metabolismo , Regeneración
5.
BMC Genomics ; 25(1): 525, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38807041

RESUMEN

BACKGROUND: The Rh blood group system is characterized by its complexity and polymorphism, encompassing 56 different antigens. Accurately predicting the presence of the C antigen using genotyping methods has been challenging. The objective of this study was to evaluate the accuracy of various genotyping methods for predicting the Rh C and to identify a suitable method for the Chinese Han population. METHODS: In total, 317 donors, consisting 223 D+ (including 20 with the Del phenotype) and 94 D- were randomly selected. For RHC genotyping, 48C and 109bp insertion were detected on the Real-time PCR platform and -292 substitution was analyzed via restriction fragment length polymorphism (RFLP). Moreover, the promoter region of the RHCE gene was sequenced to search for other nucleotide substitutions between RHC and RHc. Agreement between prediction methods was evaluated using the Kappa statistic, and comparisons between methods were conducted via the χ2 test. RESULTS: The analysis revealed that the 48C allele, 109bp insertion, a specific pattern observed in RFLP results, and wild-type alleles of seven single nucleotide polymorphisms (SNPs) were in strong agreement with the Rh C, with Kappa coefficients exceeding 0.8. However, there were instances of false positives or false negatives (0.6% false negative rate for 109bp insertion and 5.4-8.2% false positive rates for other methods). The 109bp insertion method exhibited the highest accuracy in predicting the Rh C, at 99.4%, compared to other methods (P values≤0.001). Although no statistical differences were found among other methods for predicting Rh C (P values>0.05), the accuracies in descending order were 48C (94.6%) > rs586178 (92.7%) > rs4649082, rs2375313, rs2281179, rs2072933, rs2072932, and RFLP (92.4%) > rs2072931 (91.8%). CONCLUSIONS: None of the methods examined can independently and accurately predict the Rh C. However, the 109bp insertion test demonstrated the highest accuracy for predicting the Rh C in the Chinese Han population. Utilizing the 109bp insertion test in combination with other methods may enhance the accuracy of Rh C prediction.


Asunto(s)
Pueblo Asiatico , Técnicas de Genotipaje , Polimorfismo de Nucleótido Simple , Sistema del Grupo Sanguíneo Rh-Hr , Humanos , Sistema del Grupo Sanguíneo Rh-Hr/genética , Pueblo Asiatico/genética , Técnicas de Genotipaje/métodos , China , Genotipo , Alelos , Polimorfismo de Longitud del Fragmento de Restricción , Frecuencia de los Genes , Regiones Promotoras Genéticas , Pueblos del Este de Asia
6.
Mol Pain ; : 17448069241260349, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38795338

RESUMEN

Irritable bowel syndrome (IBS) is a prevalent functional gastrointestinal disease characterized by chronic visceral pain with a complex etiology and challenging treatment. Although accumulating evidence supports the involvement of central nervous system sensitization in the development of visceral pain, the precise molecular mechanisms remain incompletely understood. In this study, we highlight the critical regulatory role of lysine-specific demethylase 6B (KDM6B) in the anterior cingulate cortex (ACC) in chronic visceral pain. To simulate clinical IBS conditions, we utilized the neonatal maternal deprivation (NMD) mouse model. Our results demonstrated that NMD induced chronic visceral pain and anxiety-like behaviors in mice. Notably, the protein expression level of KDM6B significantly increased in the ACC of NMD mice, leading to a reduction in the expression level of H32K7me3. Immunofluorescence staining revealed that KDM6B primarily co-localizes with neurons in the ACC, with minimal presence in microglia and astrocytes. Injecting GSK-J4 (a KDM6B-specific inhibitor) into ACC of NMD mice, resulted in a significant alleviation in chronic visceral pain and anxiety-like behaviors, as well as a remarkable reduction in NR2B expression level. ChIP assay further indicated that KDM6B regulates NR2B expression by influencing the demethylation of H3K27me3. In summary, our findings underscore the critical role of KDM6B in regulating chronic visceral pain and anxiety-like behaviors in NMD mice. These insights provide a basis for further understanding the molecular pathways involved in IBS and may pave the way for targeted therapeutic interventions.

7.
BMC Immunol ; 25(1): 16, 2024 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-38347480

RESUMEN

OBJECTIVE: The study aimed to explore the mechanism of artemisinin in treating primary Sjögren's syndrome (pSS) based on network pharmacology and experimental validation. METHODS: Relevant targets of the artemisinin and pSS-related targets were integrated by public databases online. An artemisinin-pSS network was constructed by Cytoscape. The genes of artemisinin regulating pSS were imported into STRING database to construct a protein-protein interaction (PPI) network in order to predict the key targets. The enrichment analyses were performed to predict the crucial mechanism and pathway of artemisinin against pSS. The active component of artemisinin underwent molecular docking with the key proteins. Artemisinin was administered intragastrically to SS-like NOD/Ltj mice to validate the efficacy and critical mechanisms. RESULTS: Network Pharmacology analysis revealed that artemisinin corresponded to 412 targets, and pSS related to 1495 genes. There were 40 intersection genes between artemisinin and pSS. KEGG indicated that therapeutic effects of artemisinin on pSS involves IL-17 signaling pathway, HIF-1 signaling pathway, apoptosis signaling pathway, Th17 cell differentiation, PI3K-Akt signaling pathway, and MAPK signaling pathway. Molecular docking results further showed that the artemisinin molecule had higher binding energy by combining with the key nodes in IL-17 signaling pathway. In vivo experiments suggested artemisinin can restored salivary gland secretory function and improve the level of glandular damage of NOD/Ltj mice. It contributed to the increase of regulatory T cells (Tregs) and the downregulated secretion of IL-17 in NOD/Ltj model. CONCLUSION: The treatment of pSS with artemisinin is closely related to modulating the balance of Tregs and Th17 cells via T cell differentiation.


Asunto(s)
Artemisininas , Síndrome de Sjögren , Ratones , Animales , Ratones Endogámicos NOD , Interleucina-17 , Simulación del Acoplamiento Molecular , Farmacología en Red , Fosfatidilinositol 3-Quinasas , Síndrome de Sjögren/tratamiento farmacológico , Artemisininas/farmacología , Artemisininas/uso terapéutico
8.
Anal Chem ; 96(8): 3335-3344, 2024 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-38363654

RESUMEN

Metabolomics has emerged as a powerful tool in biomedical research to understand the pathophysiological processes and metabolic biomarkers of diseases. Nevertheless, it is a significant challenge in metabolomics to identify the reliable core metabolites that are closely associated with the occurrence or progression of diseases. Here, we proposed a new research framework by integrating detection-based metabolomics with computational network biology for function-guided and network-based identification of core metabolites, namely, FNICM. The proposed FNICM methodology is successfully utilized to uncover ulcerative colitis (UC)-related core metabolites based on the significantly perturbed metabolic subnetwork. First, seed metabolites were screened out using prior biological knowledge and targeted metabolomics. Second, by leveraging network topology, the perturbations of the detected seed metabolites were propagated to other undetected ones. Ultimately, 35 core metabolites were identified by controllability analysis and were further hierarchized into six levels based on confidence level and their potential significance. The specificity and generalizability of the discovered core metabolites, used as UC's diagnostic markers, were further validated using published data sets of UC patients. More importantly, we demonstrated the broad applicability and practicality of the FNICM framework in different contexts by applying it to multiple clinical data sets, including inflammatory bowel disease, colorectal cancer, and acute coronary syndrome. In addition, FNICM was also demonstrated as a practicality methodology to identify core metabolites correlated with the therapeutic effects of Clematis saponins. Overall, the FNICM methodology is a new framework for identifying reliable core metabolites for disease diagnosis and drug treatment from a systemic and a holistic perspective.


Asunto(s)
Colitis Ulcerosa , Metabolómica , Humanos , Metabolómica/métodos , Biología Computacional/métodos , Colitis Ulcerosa/diagnóstico
9.
Biochem Biophys Res Commun ; 691: 149314, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38039831

RESUMEN

P: -glycoprotein (P-gp/ABCB1) overexpression is one of the primary causes of multidrug resistance (MDR). Therefore, it is crucial to discover effective pharmaceuticals to combat multidrug resistance mediated by ABCB1. Pemigatinib is a selective the fibroblast growth factor receptor (FGFR) inhibitor that is used to treat a variety of solid tumors, Clinical Trials for Urothelial Carcinoma (NCT02872714) completed its research on Pemigatinib. This study aimed to determine whether Pemigatinib can reverse ABCB1-mediated multidrug resistance, as well as its mechanism of action. Pemigatinib substantially reversed ABCB1-mediated multidrug resistance, as determined by a CCK8 assay, and immunofluorescence experiments revealed that Pemigatinib had no effect on the intracellular localization of ABCB1. Pemigatinib was discovered to increase intracellular drug accumulation, thereby reversing multidrug resistance. In addition, Docking analysis revealed that Pemigatinib and ABCB1 have a high affinity for one another. This study concludes that Pemigatinib is capable of reversing the multidrug resistance mediated by ABCB1, offering ideas and references for the clinical application of Pemigatinib.


Asunto(s)
Antineoplásicos , Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Humanos , Antineoplásicos/farmacología , Antineoplásicos/metabolismo , Resistencia a Antineoplásicos , Línea Celular Tumoral , Resistencia a Múltiples Medicamentos , Subfamilia B de Transportador de Casetes de Unión a ATP
10.
Am J Gastroenterol ; 119(4): 655-661, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37975609

RESUMEN

INTRODUCTION: Whether 10-day short-course vonoprazan-amoxicillin dual therapy (VA-dual) is noninferior to the standard 14-day bismuth-based quadruple therapy (B-quadruple) against Helicobacter pylori eradication has not been determined. This trial aimed to compare the eradication rate, adverse events, and compliance of 10-day VA-dual regimen with standard 14-day B-quadruple regimen as first-line H. pylori treatment. METHODS: This prospective randomized clinical trial was performed at 3 institutions in eastern China. A total of 314 treatment-naive, H. pylori -infected patients were randomly assigned in a 1:1 ratio to either 10-day VA-dual group or 14-day B-quadruple group. Eradication success was determined by 13 C-urea breath test at least 4 weeks after treatment. Eradication rates, adverse events, and compliance were compared between groups. RESULTS: Eradication rates of VA-dual and B-quadruple groups were 86.0% and 89.2% ( P = 0.389), respectively, by intention-to-treat (ITT) analysis; 88.2% and 91.5% ( P = 0.338), respectively, by modified ITT analysis; and 90.8% and 91.3% ( P = 0.884), respectively, by per-protocol (PP) analysis. The efficacy of the VA-dual remained noninferior to B-quadruple therapy in all ITT, modified ITT, and PP analyses. The incidence of adverse events in the VA-dual group was significantly lower compared with that in the B-quadruple group ( P < 0.001). Poor compliance contributed to eradication failure in the VA-dual group ( P < 0.001), while not in the B-quadruple group ( P = 0.110). DISCUSSION: The 10-day VA-dual therapy provided satisfactory eradication rates of >90% (PP analysis) and lower rates of adverse events compared with standard 14-day B-quadruple therapy as first-line H. pylori therapy. TRAIL REGISTRATION NUMBER: ChiCTR2300070100.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Pirroles , Sulfonamidas , Humanos , Amoxicilina/uso terapéutico , Bismuto/uso terapéutico , Bismuto/efectos adversos , Antibacterianos , Infecciones por Helicobacter/tratamiento farmacológico , Estudios Prospectivos , Quimioterapia Combinada , Cumplimiento de la Medicación , Resultado del Tratamiento , Inhibidores de la Bomba de Protones/efectos adversos
11.
Chemistry ; 30(8): e202303519, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38018776

RESUMEN

Three unusual ajmaline-macroline type bisindole alkaloids, alsmaphylines A-C, together with their postulated biogenetic precursors, were isolated from the stem barks and leaves of Alstonia macrophylla via the building blocks-based molecular network (BBMN) strategy. Alsmaphyline A represents a rare ajmaline-macroline type bisindole alkaloid with an S-shape polycyclic ring system. Alsmaphylines B and C are two novel ajmaline-macroline type bisindole alkaloids with N-1-C-21' linkages, and the former possesses an unconventional stacked conformation due to the presence of intramolecular noncovalent interactions. The chemical structures including absolute configurations of alsmaphylines A-C were established by comprehensive spectroscopic analyses, electronic circular dichroism (ECD) calculations, and single-crystal X-ray crystallography. In addition, a plausible biosynthetic pathway of these bisindole alkaloids as well as their ability to promote the protein synthesis on HT22 cells were discussed.


Asunto(s)
Alcaloides , Alstonia , Oxindoles , Alstonia/química , Ajmalina , Alcaloides Indólicos/química , Estructura Molecular , Alcaloides/química
12.
Mol Psychiatry ; 28(3): 1383-1395, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36481932

RESUMEN

In response to stressful events, the hypothalamic-pituitary-adrenal (HPA) axis is activated, and consequently glucocorticoids are released by the adrenal gland into the blood circulation. A large body of research has illustrated that excessive glucocorticoids in the hippocampus exerts negative feedback regulation of the HPA axis through glucocorticoid receptor (GR), which is critical for the homeostasis of the HPA axis. Maternal prenatal stress causes dysfunction of the HPA axis feedback mechanism in their offspring in adulthood. Here we report that telomerase reverse transcriptase (TERT) gene knockout causes hyperactivity of the HPA axis without hippocampal GR deficiency. We found that the level of TERT in the dentate gyrus (DG) of the hippocampus during the developmental stage determines the responses of the HPA axis to stressful events in adulthood through modulating the excitability of the dentate granular cells (DGCs) rather than the expression of GR. Our study also suggests that the prenatal high level of glucocorticoids exposure-induced hypomethylation at Chr13:73764526 in the first exon of mouse Tert gene accounted for TERT deficiency in the DG and HPA axis abnormality in the adult offspring. This study reveals a novel GR-independent mechanism underlying prenatal stress-associated HPA axis impairment, providing a new angle for understanding the mechanisms for maintaining HPA axis homeostasis.


Asunto(s)
Sistema Hipotálamo-Hipofisario , Receptores de Glucocorticoides , Femenino , Embarazo , Animales , Ratones , Sistema Hipotálamo-Hipofisario/metabolismo , Receptores de Glucocorticoides/metabolismo , Glucocorticoides/metabolismo , Sistema Hipófiso-Suprarrenal/metabolismo , Homeostasis
13.
Biomacromolecules ; 25(3): 1923-1932, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38394470

RESUMEN

Fatty acid cellulose esters (FACE) are common cellulose-based thermoplastics, and their thermoplasticity is determined by both the contents and the lengths of the side chains. Herein, various FACE were synthesized by the ball-milling esterification of cellulose and fatty acyl chlorides containing 10-18 carbons, and their structures and thermoplasticity were thoroughly studied. The results showed that FACE with high degrees of substitution (DS) and low melting flow temperatures (Tf) were achieved as the chain lengths of the fatty acyl chlorides were reduced. In particular, a cellulose decanoate with a DS of 1.85 and a Tf of 186 °C was achieved by feeding 3 mol of decanoyl chloride per mole anhydroglucose units of cellulose. However, cellulose stearate (DS = 1.53) synthesized by the same protocols cannot melt even at 250 °C. More interestingly, the fatty acyl chlorides with 10 and 12 carbons resulted in FACE with superior toughness (elongation at break up to 94.4%). In contrast, due to their potential crystallization of the fatty acyl groups with 14-18 carbons, the corresponding FACE showed higher tensile strength and Young's modulus than the others. This study provides some theoretical basis for the mechanochemical synthesis of thermoplastic FACE with designated properties.


Asunto(s)
Cloruros , Ésteres , Ésteres/química , Estudios de Factibilidad , Esterificación , Celulosa/química
14.
Int J Legal Med ; 138(5): 2037-2047, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38802694

RESUMEN

In forensic practice, determining the postmortem submersion interval (PMSI) and cause-of-death of cadavers in aquatic ecosystems has always been challenging task. Traditional approaches are not yet able to address these issues effectively and adequately. Our previous study proposed novel models to predict the PMSI and cause-of-death based on metabolites of blood from rats immersed in freshwater. However, with the advance of putrefaction, it is hardly to obtain blood samples beyond 3 days postmortem. To further assess the feasibility of PMSI estimation and drowning diagnosis in the later postmortem phase, gastrocnemius, the more degradation-resistant tissue, was collected from drowned rats and postmortem submersion model in freshwater immediately after death, and at 1 day, 3 days, 5 days, 7 days, and 10 days postmortem respectively. Then the samples were analyzed with liquid chromatography-tandem mass spectrometry (LC-MS/MS) to investigate the dynamic changes of the metabolites. A total of 924 metabolites were identified. Similar chronological changes of gastrocnemius metabolites were observed in the drowning and postmortem submersion groups. The difference in metabolic profiles between drowning and postmortem submersion groups was only evident in the initial 1 day postmortem, which was faded as the PMSI extension. Nineteen metabolites representing temporally-dynamic patterns were selected as biomarkers for PMSI estimation. A regression model was built based on these biomarkers with random forest algorithm, which yielded a mean absolute error (± SE) of 5.856 (± 1.296) h on validation samples from an independent experiment. These findings added to our knowledge of chronological changes in muscle metabolites from submerged vertebrate remains during decomposition, which provided a new perspective for PMSI estimation.


Asunto(s)
Ahogamiento , Agua Dulce , Inmersión , Metabolómica , Modelos Animales , Músculo Esquelético , Cambios Post Mortem , Animales , Músculo Esquelético/metabolismo , Ahogamiento/diagnóstico , Ahogamiento/metabolismo , Masculino , Cromatografía Liquida , Espectrometría de Masas en Tándem , Ratas , Ratas Sprague-Dawley , Biomarcadores/metabolismo
15.
Inorg Chem ; 63(31): 14345-14353, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39033409

RESUMEN

A biocompatible metal-organic framework (MOF), named HSTC-4, constructed using the flexible 4,4'-oxybis(benzoic acid) (OBA), was developed to enable efficient loading and controlled release of vitamin C (VC) through a combination of strategies involving ligand length, structure design, and metal selection. The kinetic product HSTC-4 demonstrates a propensity for transforming into the thermodynamically stable HSTC-5 under external stimuli, such as photoillumination and vacuum heating, as witnessed by single-crystal to single-crystal transformation. Density functional theory (DFT) calculations reveal that the VC guest molecules exhibit stronger binding affinity with HSTC-5 due to its narrower pores compared to HSTC-4, resulting in a slower release of VC from VC@HSTC-5. Furthermore, precise control over VC release can be achieved by introducing surface modifications involving SiO2 onto the structure of VC@HSCT-5, while simultaneously adjusting environmental factors such as pH and temperature conditions. Preliminary cell culture experiments and cytotoxicity assays highlight the biocompatibility of HSTC-5, suggesting that it is a promising platform for sustained drug delivery and diverse biomedical applications.


Asunto(s)
Ácido Ascórbico , Estructuras Metalorgánicas , Termodinámica , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Ácido Ascórbico/química , Cinética , Humanos , Teoría Funcional de la Densidad , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos/química , Estructura Molecular , Liberación de Fármacos
16.
BMC Infect Dis ; 24(1): 533, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38802753

RESUMEN

BACKGROUND: Hepatitis B virus (HBV) infection can cause liver failure, while individuals with Acquired Immunodeficiency Virus Disease (AIDS) are highly susceptible to various opportunistic infections, which can occur concurrently. The treatment process is further complicated by the potential occurrence of immune reconstitution inflammatory syndrome (IRIS), which presents significant challenges and contributes to elevated mortality rates. CASE PRESENTATION: The 50-year-old male with a history of chronic hepatitis B and untreated human immunodeficiency virus (HIV) infection presented to the hospital with a mild cough and expectoration, revealing multi-drug resistant pulmonary tuberculosis (MDR-PTB), which was confirmed by XpertMTB/RIF PCR testing and tuberculosis culture of bronchoalveolar lavage fluid (BALF). The patient was treated with a regimen consisting of linezolid, moxifloxacin, cycloserine, pyrazinamide, and ethambutol for tuberculosis, as well as a combination of bictegravir/tenofovir alafenamide/emtricitabine (BIC/TAF/FTC) for HBV and HIV viral suppression. After three months of treatment, the patient discontinued all medications, leading to hepatitis B virus reactivation and subsequent liver failure. During the subsequent treatment for AIDS, HBV, and drug-resistant tuberculosis, the patient developed disseminated cryptococcal disease. The patient's condition worsened during treatment with liposomal amphotericin B and fluconazole, which was ultimately attributed to IRIS. Fortunately, the patient achieved successful recovery after appropriate management. CONCLUSION: Enhancing medical compliance is crucial for AIDS patients, particularly those co-infected with HBV, to prevent HBV reactivation and subsequent liver failure. Furthermore, conducting a comprehensive assessment of potential infections in patients before resuming antiviral therapy is essential to prevent the occurrence of IRIS. Early intervention plays a pivotal role in improving survival rates.


Asunto(s)
Criptococosis , Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis Pulmonar , Humanos , Masculino , Persona de Mediana Edad , Criptococosis/tratamiento farmacológico , Criptococosis/microbiología , Criptococosis/complicaciones , Tuberculosis Pulmonar/tratamiento farmacológico , Tuberculosis Pulmonar/complicaciones , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/complicaciones , Fallo Hepático/virología , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Hepatitis B Crónica/complicaciones , Hepatitis B Crónica/tratamiento farmacológico , Coinfección/tratamiento farmacológico , Coinfección/microbiología , Coinfección/virología , Antituberculosos/uso terapéutico , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Infecciones Oportunistas Relacionadas con el SIDA/microbiología
17.
Nicotine Tob Res ; 26(4): 474-483, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-37535700

RESUMEN

INTRODUCTION: Electronic cigarettes (E-cigs) are in a controversial state. Although E-cig aerosol generally contains fewer harmful substances than smoke from burned traditional cigarettes, aerosol along with other compounds of the E-cigs may also affect lung functions and promote the development of lung-related diseases. We investigated the effects of E-cig on the pulmonary functions of male C57BL/6 mice and reveal the potential underlying mechanisms. METHODS: A total of 60 male C57BL/6 mice were randomly divided into four groups. They were exposed to fresh-air, traditional cigarette smoke, E-cig vapor with 12 mg/mL of nicotine, and E-cig with no nicotine for 8 weeks. Lung functions were evaluated by using quantitative analysis of the whole body plethysmograph, FlexiVent system, lung tissue histological and morphometric analysis, and RT-PCR analysis of mRNA expression of inflammation-related genes. In addition, the effects of nicotine and acrolein on the survival rate and DNA damage were investigated using cultured human alveolar basal epithelial cells. RESULTS: Exposure to E-cig vapor led to significant changes in lung functions and structures including the rupture of the alveolar cavity and enlarged alveolar space. The pathological changes were also accompanied by increased expression of interleukin-6 and tumor necrosis factor-α. CONCLUSIONS: The findings of the present study indicate that the safety of E-cig should be further evaluated. IMPLICATIONS: Some people currently believe that using nicotine-free E-cigs is a safe way to smoke. However, our research shows that E-cigs can cause lung damage regardless of whether they contain nicotine.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Productos de Tabaco , Ratones , Animales , Masculino , Humanos , Nicotina/efectos adversos , Nicotina/metabolismo , Ratones Endogámicos C57BL , Pulmón , Aerosoles/farmacología
18.
BMC Cardiovasc Disord ; 24(1): 266, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773462

RESUMEN

BACKGROUND: Cardiopulmonary bypass (CPB) results in brain injury, which is primarily caused by inflammation. Ac2-26 protects against ischemic or hemorrhage brain injury. The present study was to explore the effect and mechanism of Ac2-26 on brain injury in CPB rats. METHODS: Forty-eight rats were randomized into sham, CPB, Ac, Ac/AKT1, Ac/GSK3ßi and Ac/AKT1/GSK3ßa groups. Rats in sham group only received anesthesia and in the other groups received standard CPB surgery. Rats in the sham and CPB groups received saline, and rats in the Ac, Ac/AKT1, Ac/GSK3ßi and Ac/AKT1/GSK3ßa groups received Ac2-26 immediately after CPB. Rats in the Ac/AKT1, Ac/GSK3ßi and Ac/AKT1/GSK3ßa groups were injected with shRNA, inhibitor and agonist of GSK3ß respectively. The neurological function score, brain edema and histological score were evaluated. The neuronal survival and hippocampal pyroptosis were assessed. The cytokines, activity of NF-κB, S100 calcium-binding protein ß(S100ß) and neuron-specific enolase (NSE), and oxidative were tested. The NLRP3, cleaved-caspase-1 and cleaved-gadermin D (GSDMD) in the brain were also detected. RESULTS: Compared to the sham group, all indicators were aggravated in rats that underwent CPB. Compared to the CPB group, Ac2-26 significantly improved neurological scores and brain edema and ameliorated pathological injury. Ac2-26 reduced the local and systemic inflammation, oxidative stress response and promoted neuronal survival. Ac2-26 reduced hippocampal pyroptosis and decreased pyroptotic proteins in brain tissue. The protection of Ac2-26 was notably lessened by shRNA and inhibitor of GSK3ß. The agonist of GSK3ß recovered the protection of Ac2-26 in presence of shRNA. CONCLUSIONS: Ac2-26 significantly improved neurological function, reduced brain injury via regulating inflammation, oxidative stress response and pyroptosis after CPB. The protective effect of Ac2-26 primarily depended on AKT1/ GSK3ß pathway.


Asunto(s)
Puente Cardiopulmonar , Modelos Animales de Enfermedad , Glucógeno Sintasa Quinasa 3 beta , Proteínas Proto-Oncogénicas c-akt , Piroptosis , Ratas Sprague-Dawley , Transducción de Señal , Animales , Puente Cardiopulmonar/efectos adversos , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Piroptosis/efectos de los fármacos , Masculino , Neuronas/efectos de los fármacos , Neuronas/patología , Neuronas/metabolismo , Neuronas/enzimología , Fármacos Neuroprotectores/farmacología , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Edema Encefálico/prevención & control , Edema Encefálico/metabolismo , Edema Encefálico/enzimología , Edema Encefálico/patología , Antiinflamatorios/farmacología , Ratas , Subunidad beta de la Proteína de Unión al Calcio S100/metabolismo , Mediadores de Inflamación/metabolismo
19.
Bioorg Chem ; 151: 107664, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39079392

RESUMEN

Eleven undescribed monoterpenoid bisindole alkaloids, alstomaphyines A-K (1-11), along with three known analogues were isolated from the leaves and stem bark of the Alstonia macrophylla. Compounds 1-3 were unprecedented dimerization alkaloids incorporating a macroline-type motif with an ajmaline-type motif via a C-C linkage. Their structures and absolute configurations were elucidated by extensive spectroscopic analysis, electronic circular dichroism (ECD) calculation, and CD exciton chirality method. Compounds 1-3 displayed potential inhibitory bioactivity against AChE with IC50 values of 4.44 ± 0.35, 3.59 ± 0.18, and 3.71 ± 0.23 µM, respectively. Enzyme kinetic study revealed compounds 1-3 as mixed competitive AChE inhibitors. Besides, compounds 8 and 12-14 exhibited better cytotoxicity against human cancer cell line HT-29 than cisplatin. Flow cytometry data revealed that compounds 8, 13, and 14 significantly induced the HT-29 cells arrest in G0/G1 phase in a concentration-dependent manner.

20.
Artif Life ; 30(1): 106-135, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38393968

RESUMEN

Nowadays, interdisciplinary fields between Artificial Life, artificial intelligence, computational biology, and synthetic biology are increasingly emerging into public view. It is necessary to reconsider the relations between the material body, identity, the natural world, and the concept of life. Art is known to pave the way to exploring and conveying new possibilities. This survey provides a literature review on recent works of Artificial Life in visual art during the past 40 years, specifically in the computational and software domain. Having proposed a set of criteria and a taxonomy, we briefly analyze representative artworks of different categories. We aim to provide a systematic overview of how artists are understanding nature and creating new life with modern technology.


Asunto(s)
Arte , Inteligencia Artificial , Vida Artificial , Programas Informáticos , Encuestas y Cuestionarios
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA