Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 296
Filtrar
Más filtros

Base de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
medRxiv ; 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39281763

RESUMEN

Arterial pulsation is crucial for promoting fluid circulation and for influencing neuronal activity. Previous studies assessed the pulsatility index based on blood flow velocity pulsatility in relatively large cerebral arteries of human. Here, we introduce a novel method to quantify the volumetric pulsatility of cerebral microvasculature across cortical layers and in white matter (WM), using high-resolution 4D vascular space occupancy (VASO) MRI with simultaneous recording of pulse signals at 7T. Microvascular volumetric pulsatility index (mvPI) and cerebral blood volume (CBV) changes across cardiac cycles are assessed through retrospective sorting of VASO signals into cardiac phases and estimating mean CBV in resting state (CBV0) by arterial spin labeling (ASL) MRI at 7T. Using data from 11 young (28.4±5.8 years) and 7 older (61.3±6.2 years) healthy participants, we investigated the aging effect on mvPI and compared microvascular pulsatility with large arterial pulsatility assessed by 4D-flow MRI. We observed the highest mvPI in the cerebrospinal fluid (CSF) on the cortical surface (0.19±0.06), which decreased towards the cortical layers as well as in larger arteries. In the deep WM, a significantly increased mvPI (p = 0.029) was observed in the older participants compared to younger ones. Additionally, mvPI in deep WM is significantly associated with the velocity pulsatility index (vePI) of large arteries (r = 0.5997, p = 0.0181). We further performed test-retest scans, non-parametric reliability test and simulations to demonstrate the reproducibility and accuracy of our method. To the best of our knowledge, our method offers the first in vivo measurement of microvascular volumetric pulsatility in human brain which has implications for cerebral microvascular health and its relationship research with glymphatic system, aging and neurodegenerative diseases.

2.
Proc Natl Acad Sci U S A ; 121(39): e2316161121, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39298490

RESUMEN

Uveitis is a vision-threatening disease primarily driven by a dysregulated immune response, with retinal microglia playing a pivotal role in its progression. Although the transcription factor EGR2 is known to be closely associated with uveitis, including Vogt-Koyanagi-Harada disease and Behcet's disease, and is essential for maintaining the dynamic homeostasis of autoimmunity, its exact role in uveitis remains unclear. In this study, diminished EGR2 expression was observed in both retinal microglia from experimental autoimmune uveitis (EAU) mice and inflammation-induced human microglia cell line (HMC3). We constructed a mice model with conditional knockout of EGR2 in microglia and found that EGR2 deficiency resulted in increased intraocular inflammation. Meanwhile, EGR2 overexpression downregulated the expression of inflammatory cytokines as well as cell migration and proliferation in HMC3 cells. Next, RNA sequencing and ChIP-PCR results indicated that EGR2 directly bound to its downstream target growth differentiation factor 15 (GDF15) and further regulated GDF15 transcription. Furthermore, intravitreal injection of GDF15 recombinant protein was shown to ameliorate EAU progression in vivo. Meanwhile, knockdown of GDF15 reversed the phenotype of EGR2 overexpression-induced microglial inflammation in vitro. In summary, this study highlighted the protective role of the transcription factor EGR2 in AU by modulating the microglial phenotype. GFD15 was identified as a downstream target of EGR2, providing a unique target for uveitis treatment.


Asunto(s)
Enfermedades Autoinmunes , Proteína 2 de la Respuesta de Crecimiento Precoz , Factor 15 de Diferenciación de Crecimiento , Microglía , Uveítis , Animales , Humanos , Ratones , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/genética , Enfermedades Autoinmunes/patología , Enfermedades Autoinmunes/metabolismo , Línea Celular , Modelos Animales de Enfermedad , Proteína 2 de la Respuesta de Crecimiento Precoz/metabolismo , Proteína 2 de la Respuesta de Crecimiento Precoz/genética , Factor 15 de Diferenciación de Crecimiento/metabolismo , Factor 15 de Diferenciación de Crecimiento/genética , Ratones Endogámicos C57BL , Ratones Noqueados , Microglía/metabolismo , Microglía/patología , Fenotipo , Retina/metabolismo , Retina/patología , Uveítis/inmunología , Uveítis/metabolismo , Uveítis/patología , Uveítis/genética
3.
Front Endocrinol (Lausanne) ; 15: 1429165, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39268242

RESUMEN

Purpose: Studies have demonstrated that hormonal imbalance, such as elevated level of estrogen or reduced level of progesterone, was the main inducing factor of uterine leiomyoma (UL) development and some cancers. UL has been reported to be associated with several cancers in observational studies. However, the causal associations between UL and cancers remain unclear. Methods: A two-sample Mendelian randomization (MR) analysis was conducted to investigate the causal associations between UL and 16 site-specific cancers using the public databases. Four methods, namely, the inverse variance weighting (IVW), MR-Egger, weighted median, and weighted mode, were applied in our MR analysis. Sensitivity tests were also performed to evaluate the robustness of these causal associations. Results: The IVW analysis indicated that genetically predicted UL increased the risk of low malignant potential ovarian cancer [odds ratio (OR) = 1.22, 95% confidence interval (CI): 1.06-1.40, p = 0.004], serous ovarian cancer (OR = 1.29, 95% CI: 1.10-1.52, p = 0.002), invasive mucinous ovarian cancer (OR = 1.24, 95% CI: 1.08-1.44, p = 0.003), clear cell ovarian cancer (OR = 1.25, 95% CI: 1.03-1.51, p = 0.023), breast cancer (OR = 1.07, 95% CI: 1.02-1.11, p = 0.002), and brain tumor (OR = 1.23, 95% CI: 1.06-1.42, p = 0.007). Conversely, genetically predicted UL reduced the risk of gastric cancer (OR = 0.91, 95% CI: 0.85-0.98, p = 0.008). The causal effects were consistent in the sensitivity analysis. Conclusions: Our results demonstrated that UL exhibits a causal relationship with high risk of several cancers. We suggest reinforcing the cancer screening in UL patients to enable the early detection of cancers.


Asunto(s)
Leiomioma , Análisis de la Aleatorización Mendeliana , Neoplasias Uterinas , Humanos , Femenino , Leiomioma/genética , Leiomioma/epidemiología , Neoplasias Uterinas/genética , Neoplasias Uterinas/epidemiología , Predisposición Genética a la Enfermedad , Factores de Riesgo , Polimorfismo de Nucleótido Simple
4.
Int J Pharm ; 665: 124709, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39306204

RESUMEN

Tenofovir amibufenamide fumarate (TMF) is the first oral drug developed in Asia for the treatment of adult patients with chronic viral hepatitis B, however, further applications are limited by poor tableting performance and high sticking propensity. In this work, the spherulitic growth process of TMF has been designed and explored with the help of molecular dynamics simulation and process analysis technologies (ATR-FTIR, FBRM and EasyViewer). The spherical particles with high bulk density, good flowability and uniform particle size distribution are prepared by a simple quenching process. More importantly, experimental results show that spherical particles have higher average tensile strength (100.8% increase), higher plastic deformability and lower amount of punch sticking (87.4% decrease in 30 tablets) compared to the commercial powder products. These contributions not only shed light on the design principle of drug spherulitic growth processes, but also provide guidance for the manufacture of high-quality tablet products.

5.
Chem Commun (Camb) ; 60(71): 9594-9597, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39141401

RESUMEN

An innovative polyphosphide route is developed to synthesize a series of P-doped PdAu ternary alloys. The alloying of P and Au optimizes the electronic structure and reduces the back-donation of d electrons to CO. Meanwhile, the generation of CO is largely inhibited by the highly selective direct pathway arising from the synergistic electron/ligand effect of Au and P, leading to a remarkable anti-poisoning capability for formic acid oxidation.

6.
J Proteome Res ; 23(9): 4005-4013, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39171377

RESUMEN

Ribosome profiling and mass spectrometry have revealed thousands of previously unannotated small and alternative open reading frames (sm/alt-ORFs) that are translated into micro/alt-proteins in mammalian cells. However, their prevalence across human tissues and biological roles remains largely undefined. The placenta is an ideal model for identifying unannotated microproteins and alt-proteins due to its considerable protein diversity that is required to sustain fetal development during pregnancy. Here, we profiled unannotated microproteins and alt-proteins in human placental tissues from preeclampsia patients or healthy individuals by proteomics, identified 52 unannotated microproteins or alt-proteins, and demonstrated that five microproteins can be translated from overexpression constructs in a heterologous cell line, although several are unstable. We further demonstrated that one microprotein, XRCC6P1, associates with translation initiation factor eIF3 and negatively regulates translation when exogenously overexpressed. Thus, we revealed a hidden sm/alt-ORF-encoded proteome in the human placenta, which may advance the mechanism studies for placenta development as well as placental disorders such as preeclampsia.


Asunto(s)
Placenta , Preeclampsia , Biosíntesis de Proteínas , Proteómica , Humanos , Embarazo , Femenino , Placenta/metabolismo , Proteómica/métodos , Preeclampsia/metabolismo , Preeclampsia/genética , Sistemas de Lectura Abierta , Factor 3 de Iniciación Eucariótica/metabolismo , Factor 3 de Iniciación Eucariótica/genética , Proteoma/análisis , Proteoma/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Micropéptidos
7.
Artículo en Inglés | MEDLINE | ID: mdl-39205643

RESUMEN

Diabetic nephropathy (DN) is recognized as one of the primary causes of chronic kidney disease and end-stage renal disease. Vaccarin (VAC) confers favorable effects on cardiovascular and metabolic diseases, including type 2 diabetes mellitus (T2DM). Nonetheless, the potential role and mechanism of VAC in the etiology of DN have yet to be completely elucidated. In this study, a classical mouse model of T2DM is experimentally induced via a high-fat diet (HFD)/streptozocin (STZ) regimen. Renal histological changes are assessed via H&E staining. Masson staining and immunohistochemistry (IHC) are employed to assess renal fibrosis. RT-PCR is utilized to quantify the mRNA levels of renal fibrosis, oxidative stress and inflammation markers. The levels of malondialdehyde (MDA) and reactive oxygen species (ROS), as well as the content of glutathione peroxidase (GSH-Px), are measured. The protein expressions of collagen I, TGF-ß1, α-SMA, E-cadherin, Nrf2, catalase, SOD3, SOD2, SOD1, p-ERK, p-EGFR (Y845), p-EGFR (Y1173), p-NFκB P65, t-ERK, t-EGFR and t-NFκB P65 are detected by western blot analysis. Our results reveal that VAC has a beneficial effect on DN mice by improving renal function and mitigating histological damage. This is achieved through its inhibition of renal fibrosis, inflammatory cytokine overproduction, and ROS generation. Moreover, VAC treatment effectively suppresses the process of epithelial-mesenchymal transition (EMT), a crucial characteristic of renal fibrosis, in high glucose (HG)-induced HK-2 cells. Network pharmacology analysis and molecular docking identify epidermal growth factor receptor (EGFR) as a potential target for VAC. Amino acid site mutations reveal that Lys-879, Ile-918, and Ala-920 of EGFR may mediate the direct binding of VAC to EGFR. In support of these findings, VAC reduces the phosphorylation levels of both EGFR and its downstream mediator, extracellular signal-regulated kinase 1/2 (ERK1/2), in diabetic kidneys and HG-treated HK-2 cells. Notably, blocking either EGFR or ERK1/2 yields renal benefits similar to those observed with VAC treatment. Therefore, this study reveals that VAC attenuates renal damage via inactivation of the EGFR/ERK1/2 signaling axis in T2DM patients.

8.
Pharmaceuticals (Basel) ; 17(8)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39204119

RESUMEN

BACKGROUND: Type 2 diabetes mellitus (T2DM) is a metabolic syndrome characterized by chronic inflammation, insulin resistance, and islet cell damage. The prevention of T2DM and its associated complications is an urgent public health issue that affects hundreds of millions of people globally. Numerous studies suggest that disturbances in gut metabolites are important driving forces for the pathogenesis of diabetes. However, the functions and mechanisms of action of most commensal bacteria in T2DM remain largely unknown. METHODS: The quantification of bile acids (BAs) in fecal samples was performed using ultra-performance liquid chromatography-tandem mass spectrometer (UPLC-MS/MS). The anti-diabetic effects of Bacteroides uniformis (B. uniformis) and its metabolites cholic acid (CA) and chenodeoxycholic acid (CDCA) were assessed in T2DM mice induced by streptozocin (STZ) plus high-fat diet (HFD). RESULTS: We found that the abundance of B. uniformis in the feces and the contents of CA and CDCA were significantly downregulated in T2DM mice. B. uniformis was diminished in diabetic individuals and this bacterium was sufficient to promote the production of BAs. Colonization of B. uniformis and intragastric gavage of CA and CDCA effectively improved the disorder of glucose and lipid metabolism in T2DM mice by inhibiting gluconeogenesis and lipolysis in the liver. CA and CDCA improved hepatic glucose and lipid metabolism by acting on the Takeda G protein-coupled receptor 5 (TGR5)/adenosine monophosphate-activated protein kinase (AMPK) signaling pathway since knockdown of TGR5 minimized the benefit of CA and CDCA. Furthermore, we screened a natural product-vaccarin (VAC)-that exhibited anti-diabetic effects by promoting the growth of B. uniformis in vitro and in vivo. Gut microbiota pre-depletion abolished the favorable effects of VAC in diabetic mice. CONCLUSIONS: These data suggest that supplementation of B. uniformis may be a promising avenue to ameliorate T2DM by linking the gut and liver.

9.
Int J Biol Macromol ; 279(Pt 1): 134660, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39134196

RESUMEN

Checkpoint blockades have emerged as a frontline approach in cancer management, designed to enhance the adaptive immune response against tumors. However, its clinical efficacy is limited to a narrow range of tumor types, which necessitates the exploration of novel strategies that target another main branch of the immune system. One such potential strategy is the therapeutic modulation of pattern recognition receptors (PRRs) pathways in innate immune cells, which have shown promise in tumor eradication. Previously, a ß-1,3/1,6-glucan with high purity from Durvillaea antarctica (BG136) was reported by our group to exhibit pan-antitumor effects. In the current study, we systemically studied the antitumor activity of BG136 in combination with anti-PD1 antibody in MC38 syngeneic tumor model in vivo. Integrated transcriptomic and metabolomic analyses suggested that BG136 enhanced the antitumor immunity of anti-PD1 antibody by reprogramming the tumor microenvironment to become more proinflammatory. In addition, an increase in innate and adaptive immune cell infiltration and activation, enhanced lipid metabolism, and a decrease in ascorbate and aldarate metabolism were also found. These findings provide mechanistic insights that support the potent antitumor efficacy of BG136 when combined with immune checkpoint inhibitor antibodies.

10.
Nano Lett ; 24(31): 9511-9519, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39042397

RESUMEN

Electrohydrodynamic printing holds both ultrahigh-resolution fabrication capability and unmatched ink-viscosity compatibility yet fails on highly insulating thick/irregular substrates. Herein, we proposed a single-potential driven electrohydrodynamic printing process with submicrometer resolution on arbitrary nonconductive targets, regardless of their geometric shape or sizes, via precoating with an ultrathin dielectric nanoparticle layer. Benefiting from the favorable Maxwell-Wagner polarization, the reversely polarized spot brought about a significant drop (∼57% for ceramics) in the operation voltage as its induced electric field and a negligible residual charge accumulation. Thus, ordered micro/nanostructures with line widths down to 300 nm were directly written at a stage speed as low as 5 mm/s, and silver features with width of ∼2 µm or interval of ∼4 µm were achieved on insulating substrates separately. Flexible sensors and curved heaters were then high-precision printed and demonstrated successfully, presenting this technique with huge potential for fabricating flexible/conformal electronics on arbitrary 3D structures.

11.
Int J Pharm ; 662: 124515, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39074649

RESUMEN

Spherical agglomeration (SA) is a processing technique that enhances the physical properties of particles, reduces the number of unit operations in pharmaceutical manufacturing, and improves process efficiency. However, one of the limitations of SA is its high nonlinearity, which makes scalability a challenge. This prospective study was designed to realize the optimization of SA process parameters of aspirin, the world's first and most widely used nonsteroidal anti-inflammatory drug, by developing a green SA model through response surface methodology. First, Plackett-Burman experiments were conducted to identify the key operating variables affecting SA, and Sustainability Index (STI) was defined to evaluate the effects of these operating variables on the SA and the energy input to the environment during the post-processing process. Furthermore, the effects of three independent variables on mean size, yield, and STI were investigated based on Box-Behnken design. A second-order regression equation with response values was developed to optimize the above three objectives. As a result, the spherical products were obtained with excellent powder properties, including anti-caking property, filtration property, and tableting performance compared to the raw materials. This work provides an experimental and modelling basis for the further application of this environmentally-friendly SA technology.


Asunto(s)
Antiinflamatorios no Esteroideos , Aspirina , Tamaño de la Partícula , Tecnología Farmacéutica , Aspirina/química , Tecnología Farmacéutica/métodos , Antiinflamatorios no Esteroideos/química , Polvos/química , Comprimidos/química , Tecnología Química Verde/métodos , Química Farmacéutica/métodos , Composición de Medicamentos/métodos , Estudios Prospectivos
12.
J Phys Chem Lett ; 15(27): 7003-7010, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38949564

RESUMEN

A BPAPTPyC organic molecule containing a sandwich structural chromophore is designed and synthesized to produce blue thermally activated delayed fluorescence (TADF). The chromophore is composed of two di(4-tert-butylphenyl)amino donors and one inserted terpyridyl acceptor hitched at positions 1, 8, and 9 of a single carbazole via the p-phenylene group, in which the multiple space π-π interactions between the donor and acceptor enable the molecule to possess the TADF feature with a high energy emission at 470 nm but a low photoluminescence quantum yield (PLQY) and a small proportion of the delayed component. In contrast, the corresponding Zn(BPAPTPyC)Cl2 complex has a high PLQY and a short lifetime with a red-shifted emission due to the enhanced rigidity and electron accepting ability of the terpyridyl group from coordination. A solution-processed organic light-emitting diode (OLED) based on the complex achieves a maximum external quantum efficiency (EQE) of 17.9% with an emission peak at 585 nm, while an OLED of the organic molecule produces blue emission with a maximum EQE of 2.7%.

13.
Opt Lett ; 49(13): 3572-3575, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38950212

RESUMEN

We demonstrate the post-induction of high-quality microcavities on a silicon photonic crystal (PC) waveguide by integrating a few-layer GaSe crystal, which promises efficient on-chip optical frequency conversions. The integration of GaSe shifts the dispersion bands of the PC waveguide mode into the bandgap, resulting in localized modes confined by the bare PC waveguides. Thanks to the small contrast of refractive index at the boundaries of the microcavity, it is reliable to obtain quality factors exceeding 104. With the enhanced light-GaSe interaction by the microcavity modes and GaSe's high second-order nonlinearity, remarkable second-harmonic generation (SHG) and sum-frequency generation (SFG) are achieved with continuous-wave (CW) lasers.

14.
Mol Cancer Res ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38967522

RESUMEN

Heterogeneous nuclear ribonucleoprotein AB (hnRNPAB) is considered a cancer-promoting heterogeneous nuclear ribonucleoprotein in many cancers, but its function in pancreatic ductal adenocarcinoma (PDAC) is poorly understood. HnRNPAB was highly expressed in PDAC tissues compared to normal pancreatic tissues, and high expression of hnRNPAB was associated with poor overall survival and recurrence-free survival in PDAC patients. HnRNPAB promotes migration and invasion of PDAC cells in vitro. In xenograft tumor mouse models, hnRNPAB deprivation significantly attenuated liver metastasis. HnRNPAB mRNA and protein levels are positively associated with MYC in PDAC cells. Mechanistically, hnRNPAB bound to MYC mRNA and prolonged its half-life of MYC mRNA. HnRNPAB induced PDAC cells to secret CXCL8 via MYC, which promoted neutrophils recruitment and facilitated tumor cells entrancing into the hepatic parenchyma. These findings point to a novel regulatory mechanism via which hnRNPAB promotes PDAC metastasis. Implications: Hnrnpab participates in the post-transcriptional regulation of the oncogene MYC by binding and stabilizing MYC mRNA, thereby promoting liver metastasis in PDAC.

15.
Chaos ; 34(7)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38985966

RESUMEN

Punishment is a common tactic to sustain cooperation and has been extensively studied for a long time. While most of previous game-theoretic work adopt the imitation learning framework where players imitate the strategies of those who are better off, the learning logic in the real world is often much more complex. In this work, we turn to the reinforcement learning paradigm, where individuals make their decisions based upon their experience and long-term returns. Specifically, we investigate the prisoners' dilemma game with a Q-learning algorithm, and cooperators probabilistically pose punishment on defectors in their neighborhood. Unexpectedly, we find that punishment could lead to either continuous or discontinuous cooperation phase transitions, and the nucleation process of cooperation clusters is reminiscent of the liquid-gas transition. The analysis of a Q-table reveals the evolution of the underlying "psychologic" changes, which explains the nucleation process and different levels of cooperation. The uncovered first-order phase transition indicates that great care needs to be taken when implementing the punishment compared to the continuous scenario.

16.
Front Neurol ; 15: 1243597, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38994494

RESUMEN

Aim: To evaluate the comparative efficacy and safety of various doses of oral cannabidiol (CBD) in treating refractory epilepsy indications, thus providing more informative evidence for clinical decision-making. Methods: A literature search of PubMed, Embase, the Cochrane library, and Web of Science (WoS) was performed to retrieve relevant randomized controlled trials (RCTs) that compared different doses of oral CBD with placebo or each other in refractory epilepsy indications. The search was limited from the inception of each database to January 3, 2023. Relative risk [RR] with a 95% confidence interval [CI] was used to express results. STATA/SE 14 was employed for network meta-analysis. Results: Six RCTs involving 972 patients were included in the final data analysis. Network meta-analysis showed that, CBD10 (10 mg/kg/day) (RR: 1.77, 95%CI: 1.28 to 2.44), CBD20 (20 mg/kg/day) (RR: 1.91, 95%CI: 1.49 to 2.46), CBD25 (25 mg/kg/day) (RR: 1.61, 95%CI: 0.96 to 2.70), and CBD50 (50 mg/kg/day) (RR: 1.78, 95%CI: 1.07 to 2.94) were associated with higher antiseizure efficacy although the pooled result for CBD25 was only close to significant. In addition, in terms of the risk of treatment-emergent adverse events (TEAEs), the difference between different doses is not significant. However, CBD20 ranked first in terms of antiseizure efficacy, followed by CBD50, CBD10, and CBD25. For TEAEs, CBD25 ranked first, followed by CBD10, CBD50, CBD5, and CBD20. Conclusion: For refractory indications, CBD20 may be optimal option for antiseizure efficacy; however, CBD25 may be best for TEAEs. Therefore, an appropriate dose of oral CBD should be selected based on the actual situation. Due to the limitations of eligible studies and the limited sample size, more studies are needed in the future to validate our findings.

18.
Inorg Chem ; 63(29): 13474-13483, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-38976574

RESUMEN

Traditional information encryption materials that rely on fluorescent/phosphorescent molecules are facing an increasing risk of counterfeiting or tampering due to their static reading mode and advances in counterfeiting technology. In this study, a series of Mg2-xZnxSnO4 (x = 0.55, 0.6, 0.65, 0.7 0.75, 0.8) that realizes the writing, reading, and erasing of dynamic information is developed. When heated to 90 °C, the materials exhibit a variety of dynamic emission changes with the concentration of Zn2+ ions. As the doping concentration increased, the ratio of the shallow trap to deep trap changed from 7.77 to 20.86. When x = 0.55, the proportion of deep traps is relatively large, resulting in a higher temperature and longer time required to read the information. When x = 0.80, the proportion of shallow traps is larger and the encrypted information is easier to read. Based on the above features, encryption binary codes device was designed, displaying dynamic writing, reading, and erasing of information under daylight and heating conditions. Accordingly, this work provides reliable guidance on advanced dynamic information encryption.

19.
medRxiv ; 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-39040201

RESUMEN

A major challenge for human neuroimaging using functional MRI is the differentiation of neuronal excitation and inhibition which may induce positive and negative BOLD responses. Here we present an innovative multi-contrast laminar functional MRI technique that offers comprehensive and quantitative imaging of neurovascular (CBF, CBV, BOLD) and metabolic (CMRO2) responses across cortical layers at 7 Tesla. This technique was first validated through a finger-tapping experiment, revealing 'double-peak' laminar activation patterns within the primary motor cortex. By employing a ring-shaped visual stimulus that elicited positive and negative BOLD responses, we further observed distinct neurovascular and metabolic responses across cortical layers and eccentricities in the primary visual cortex. This suggests potential feedback inhibition of neuronal activities in both superficial and deep cortical layers underlying the negative BOLD signals in the fovea, and also illustrates the neuronal activities in visual areas adjacent to the activated eccentricities.

20.
Front Oncol ; 14: 1361694, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38846984

RESUMEN

Background: Soft tissue tumors (STTs) are benign or malignant superficial neoplasms arising from soft tissues throughout the body with versatile pathological types. Although Ultrasonography (US) is one of the most common imaging tools to diagnose malignant STTs, it still has several drawbacks in STT diagnosis that need improving. Objectives: The study aims to establish this deep learning (DL) driven Artificial intelligence (AI) system for predicting malignant STTs based on US images and clinical indexes of the patients. Methods: We retrospectively enrolled 271 malignant and 462 benign masses to build the AI system using 5-fold validation. A prospective dataset of 44 malignant masses and 101 benign masses was used to validate the accuracy of system. A multi-data fusion convolutional neural network, named ultrasound clinical soft tissue tumor net (UC-STTNet), was developed to combine gray scale and color Doppler US images and clinic features for malignant STTs diagnosis. Six radiologists (R1-R6) with three experience levels were invited for reader study. Results: The AI system achieved an area under receiver operating curve (AUC) value of 0.89 in the retrospective dataset. The diagnostic performance of the AI system was higher than that of one of the senior radiologists (AUC of AI vs R2: 0.89 vs. 0.84, p=0.022) and all of the intermediate and junior radiologists (AUC of AI vs R3, R4, R5, R6: 0.89 vs 0.75, 0.81, 0.80, 0.63; p <0.01). The AI system also achieved an AUC of 0.85 in the prospective dataset. With the assistance of the system, the diagnostic performances and inter-observer agreement of the radiologists was improved (AUC of R3, R5, R6: 0.75 to 0.83, 0.80 to 0.85, 0.63 to 0.69; p<0.01). Conclusion: The AI system could be a useful tool in diagnosing malignant STTs, and could also help radiologists improve diagnostic performance.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA