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1.
PLoS Biol ; 22(1): e3002470, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38206965

RESUMO

The bridging integrator 1 (BIN1) gene is an important risk locus for late-onset Alzheimer's disease (AD). BIN1 protein has been reported to mediate tau pathology, but the underlying molecular mechanisms remain elusive. Here, we show that neuronal BIN1 is cleaved by the cysteine protease legumain at residues N277 and N288. The legumain-generated BIN1 (1-277) fragment is detected in brain tissues from AD patients and tau P301S transgenic mice. This fragment interacts with tau and accelerates its aggregation. Furthermore, the BIN1 (1-277) fragment promotes the propagation of tau aggregates by enhancing clathrin-mediated endocytosis (CME). Overexpression of the BIN1 (1-277) fragment in tau P301S mice facilitates the propagation of tau pathology, inducing cognitive deficits, while overexpression of mutant BIN1 that blocks its cleavage by legumain halts tau propagation. Furthermore, blocking the cleavage of endogenous BIN1 using the CRISPR/Cas9 gene-editing tool ameliorates tau pathology and behavioral deficits. Our results demonstrate that the legumain-mediated cleavage of BIN1 plays a key role in the progression of tau pathology. Inhibition of legumain-mediated BIN1 cleavage may be a promising therapeutic strategy for treating AD.


Assuntos
Doença de Alzheimer , Animais , Humanos , Camundongos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Doença de Alzheimer/patologia , Encéfalo/metabolismo , Clatrina/metabolismo , Endocitose , Camundongos Transgênicos , Proteínas tau/genética , Proteínas tau/metabolismo
2.
Eur Heart J ; 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-39498862

RESUMO

BACKGROUND AND AIMS: Dendritic cells (DCs) are closely related to blood pressure (BP) regulation. Mineralocorticoid receptor (MR) is an important drug target for antihypertensive treatment. However, the role of DC MR in the pathogenesis of hypertension has not been fully elucidated. This study aimed to determine the role of DC MR in BP regulation and to explore the mechanism. METHODS: Renal biopsy and peripheral blood samples were collected from hypertensive patients (HTN) for immunostaining and flow cytometry. Dendritic cell MR knockout (DCMRKO) mice, DC MR overexpressing (DCMROV) mice, DCMROV/IL-17A knockout (DCMROV/IL-17AKO) mice and finerenone-treated C57BL/6 mice were infused with angiotensin II (Ang II) to establish hypertensive models. Western blotting, chromatin immunoprecipitation, co-immunoprecipitation, and in vivo DC depletion or adoptive transfer were used to delineate the functional importance of DC MR in hypertension development. RESULTS: Mineralocorticoid receptor antagonists (spironolactone and finerenone) suppressed DC aggregation and activation, as well as hypertension in HTN and mice. Compared with littermate control (LC) mice, dendritic cell MR knockout mice had strikingly decreased BPs and attenuated target organ damage after Ang II infusion. Flow cytometry showed that DC MR deficiency mitigated Ang II-induced DC activation and T helper 17 (Th17) cell differentiation. RNA sequencing revealed that MR-deficient DCs had elevated expression of Plcß1 and Plcß4, knockdown of which reversed the inhibitory effect of MR deficiency on DC activation and Th17 differentiation. Adoptive transfer of MR-deficient DCs protected Ang II-induced hypertension, whereas knockdown of Plcß1/4 eliminated the protective effects. At the molecular level, MR negatively regulated Plcß1/4, which recruited SHP-1 to inactivate of Stat5 activity, resulting in enhanced NF-κB activation and Th17 polarization. Furthermore, DCMROV mice manifested more elevated BPs and target organ damage than control mice after Ang II infusion, and these differences were abolished in DCMROV/IL-17AKO mice. Finally, MR antagonists decreased the aggregation of Th17 in HTN and mice. CONCLUSIONS: Dendritic cell MR plays important roles in the pathogenesis of hypertension by regulating Th17 through Plcß1/4-Stat5-NF-κB signalling, and blockade of DC MR is beneficial for treating hypertension.

3.
J Cogn Neurosci ; 36(8): 1695-1714, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38579269

RESUMO

The brain is a hierarchical modular organization that varies across functional states. Network configuration can better reveal network organization patterns. However, the multi-hierarchy network configuration remains unknown. Here, we propose an eigenmodal decomposition approach to detect modules at multi-hierarchy, which can identify higher-layer potential submodules and is consistent with the brain hierarchical structure. We defined three metrics: node configuration matrix, combinability, and separability. Node configuration matrix represents network configuration changes between layers. Separability reflects network configuration from global to local, whereas combinability shows network configuration from local to global. First, we created a random network to verify the feasibility of the method. Results show that separability of real networks is larger than that of random networks, whereas combinability is smaller than random networks. Then, we analyzed a large data set incorporating fMRI data from resting and seven distinct tasking conditions. Experiment results demonstrates the high similarity in node configuration matrices for different task conditions, whereas the tasking states have less separability and greater combinability between modules compared with the resting state. Furthermore, the ability of brain network configuration can predict brain states and cognition performance. Crucially, derived from tasks are highlighted with greater power than resting, showing that task-induced attributes have a greater ability to reveal individual differences. Together, our study provides novel perspectives for analyzing the organization structure of complex brain networks at multi-hierarchy, gives new insights to further unravel the working mechanisms of the brain, and adds new evidence for tasking states to better characterize and predict behavioral traits.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Rede Nervosa , Humanos , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Adulto , Masculino , Rede Nervosa/fisiologia , Rede Nervosa/diagnóstico por imagem , Feminino , Adulto Jovem , Mapeamento Encefálico , Conectoma , Desempenho Psicomotor/fisiologia
4.
Am J Transplant ; 24(5): 781-794, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38307416

RESUMO

We analyzed whether there is an interaction between the Kidney Donor Profile Index (KDPI) and cold ischemia time (CIT) in recipients of deceased donor kidney transplant (KTs). Adults who underwent KTs in the United States between 2014 and 2020 were included and divided into 3 KDPI groups (≤20%, 21%-85%, >85%) and 4 CIT strata (<12, 12-17.9, 18-23.9, ≥24 hours). Multivariate analyses were used to test the interaction between KDPI and CIT for the following outcomes: primary graft nonfunction (PGNF), delayed graft function (DGF), estimated glomerular filtration rate (eGFR) at 6 and 12 months, patient survival, graft survival, and death-censored graft survival (DCGS). A total of 69,490 recipients were analyzed: 18,241 (26.3%) received a graft with KDPI ≤20%, 46,953 (67.6%) with KDPI 21%-85%, and 4,296 (6.2%) with KDPI >85%. Increasing KDPI and CIT were associated with worse post-KT outcomes. Contrary to our hypothesis, howerver, the interaction between KDPI and CIT was statistically significant only for PGNF and DGF and eGFR at 6 months. Paradoxically, the negative coefficient of the interaction suggested that increasing duration of CIT was more detrimental for low and intermediate-KDPI organs relative to high-KDPI grafts. Conversely, for mortality, graft survival, and DCGS, we found that the interaction between CIT and KDPI was not statistically significant. We conclude that, high KDPI and prolonged CIT are independent risk factors for inferior outcomes after KT. Their interaction, however, is statistically significant only for the short-term outcomes and more pronounced on low and intermediate-KDPI grafts than high-KDPI kidneys.


Assuntos
Isquemia Fria , Função Retardada do Enxerto , Taxa de Filtração Glomerular , Sobrevivência de Enxerto , Transplante de Rim , Doadores de Tecidos , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Doadores de Tecidos/provisão & distribuição , Fatores de Risco , Adulto , Seguimentos , Função Retardada do Enxerto/etiologia , Prognóstico , Taxa de Sobrevida , Estudos Retrospectivos , Falência Renal Crônica/cirurgia , Rejeição de Enxerto/etiologia , Testes de Função Renal , Obtenção de Tecidos e Órgãos , Complicações Pós-Operatórias
5.
Immunogenetics ; 76(2): 123-135, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38427105

RESUMO

To examine whether circulating interleukin-6 (IL-6) levels (CirIL6) have a causal effect on blood pressure using Mendelian randomization (MR) methods. We used data from genome-wide association studies (GWAS) of European ancestry to obtain genetic instruments for circulating IL-6 levels and blood pressure measurements. We applied several robust MR methods to estimate the causal effects and to test for heterogeneity and pleiotropy. We found that circulating IL-6 had a significant positive causal effect on systolic blood pressure (SBP) and pulmonary arterial hypertension (PAH), but not on diastolic blood pressure (DBP) or hypertension. We found that as CirIL6 genetically increased, SBP increased using Inverse Variance Weighted (IVW) method (for ukb-b-20175, ß = 0.082 with SE = 0.032, P = 0.011; for ukb-a-360, ß = 0.075 with SE = 0.031, P = 0.014) and weighted median (WM) method (for ukb-b-20175, ß = 0.061 with SE = 0.022, P = 0.006; for ukb-a-360, ß = 0.065 with SE = 0.027, P = 0.014). Moreover, CirIL6 may be associated with an increased risk of PAH using WM method (odds ratio (OR) = 15.503, 95% CI, 1.025-234.525, P = 0.048), but not with IVW method. Our study provides novel evidence that circulating IL-6 has a causal role in the development of SBP and PAH, but not DBP or hypertension. These findings suggest that IL-6 may be a potential therapeutic target for preventing or treating cardiovascular diseases and metabolic disorders. However, more studies are needed to confirm the causal effects of IL-6 on blood pressure and to elucidate the underlying mechanisms and pathways.


Assuntos
Hipertensão , Interleucina-6 , Humanos , Pressão Sanguínea/genética , Interleucina-6/genética , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Hipertensão/genética
6.
Microcirculation ; 31(5): e12860, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38837938

RESUMO

OBJECTIVE: Diabetic foot ulcer (DFU) is a severe complication with high mortality. High plantar pressure and poor microcirculation are considered main causes of DFU. The specific aims were to provide a novel technique for real-time measurement of plantar skin blood flow (SBF) under walking-like pressure stimulus and delineate the first plantar metatarsal head dynamic microcirculation characteristics because of life-like loading conditions in healthy individuals. METHODS: Twenty young healthy participants (14 male and 6 female) were recruited. The baseline (i.e., unloaded) SBF of soft tissue under the first metatarsal head were measured using laser Doppler flowmetry (LDF). A custom-made machine was utilized to replicate daily walking pressure exertion for 5 min. The exerted plantar force was adjusted from 10 N (127.3 kPa) to 40 N (509.3 kPa) at an increase of 5 N (63.7 kPa). Real-time SBF was acquired using the LDF. After each pressure exertion, postload SBF was measured for comparative purposes. Statistical analysis was performed using the R software. RESULTS: All levels of immediate-load and postload SBF increased significantly compared with baseline values. As the exerted load increased, the postload and immediate-load SBF tended to increase until the exerted load reached 35 N (445.6 kPa). However, in immediate-load data, the increasing trend tended to level off as the exerted pressure increased from 15 N (191.0 kPa) to 25 N (318.3 kPa). For postload and immediate-load SBF, they both peaked at 35 N (445.6 kPa). However, when the exerted force exceeds 35 N (445.6 kPa), both the immediate-load and postload SBF values started to decrease. CONCLUSIONS: Our study offered a novel real-time plantar soft tissue microcirculation measurement technique under dynamic conditions. For the first metatarsal head of healthy people, 20 N (254.6 kPa)-plantar pressure has a fair microcirculation stimulus compared with higher pressure. There might be a pressure threshold at 35 N (445.6 kPa) for the first metatarsal head, and soft tissue microcirculation may decrease when local pressure exceeds it.


Assuntos
, Microcirculação , Pele , Humanos , Masculino , Feminino , Microcirculação/fisiologia , Adulto , Pele/irrigação sanguínea , Pele/fisiopatologia , Pé/irrigação sanguínea , Pressão , Ossos do Metatarso/irrigação sanguínea , Ossos do Metatarso/fisiopatologia , Fluxometria por Laser-Doppler/métodos , Adulto Jovem , Caminhada/fisiologia , Pé Diabético/fisiopatologia
7.
Plant Biotechnol J ; 22(3): 774-784, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37942846

RESUMO

Flowering time is of great agricultural importance and the timing and extent of flowering usually determines yield and availability of flowers, fruits and seeds. Identification of genes determining flowering has important practical applications for tomato breeding. Here we demonstrate the roles of the FANTASTIC FOUR (FAF) gene family in regulating tomato flowering time. In this plant-specific gene family, SlFAF1/2a shows a constitutive expression pattern during the transition of the shoot apical meristem (SAM) from vegetative to reproductive growth and significantly influences flowering time. Overexpressing SlFAF1/2a causes earlier flowering compared with the transformations of other genes in the FAF family. SlFAF1/2c also positively regulates tomato flowering, although to a lesser extent. The other members of the SlFAF gene family, SlFAF1/2b, SlFAF3/4a and SlFAF3/4b, are negative regulators of tomato flowering and faf1/2b, faf3/4a and faf3/4b single mutants all display early flowering. We generated a series of early flowering mutants using the CRISPR/Cas9 editing system, and the faf1/2b faf3/4a faf3/4b triple mutant flowering earliest compared with other mutants. More importantly, these mutants show no adverse effect on yield. Our results have uncovered the role of the FAF gene family in regulating tomato flowering time and generated early flowering germplasms for molecular breeding.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sistemas CRISPR-Cas/genética , Melhoramento Vegetal , Mutação/genética , Flores , Regulação da Expressão Gênica de Plantas/genética
8.
Chemistry ; : e202403515, 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39420133

RESUMO

Two new non-centrosymmetric chalcogenides, ACuGa6S10 (A = Rb, Cs) have been successfully synthesized by an "iterative substitution" strategy based on chalcopyrite CuFeS2 structural template. Benefiting from the substitution of Fe3+ cations by Ga3+ cations, ACuGa6S10 (A = Rb, Cs) exhibit wide suitable band gap of 2.48 and 2.40 eV, respectively, which is about five times higher than their structure template CuFeS2, and the large second harmonic generation response (1.5 and 1.8 × AgGaS2). Combining theoretical calculation and structural analysis confirm that the [GaS4] tetrahedra make the main contribution on their good liner and nonlinear optical (NLO) performances. The "iterative substitution" strategy expands the design idea of materials and can lead to the discovery of a large number of IR NLO compounds.

9.
PLoS Comput Biol ; 19(4): e1011019, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37036844

RESUMO

Neurons, represented as a tree structure of morphology, have various distinguished branches of dendrites. Different types of synaptic receptors distributed over dendrites are responsible for receiving inputs from other neurons. NMDA receptors (NMDARs) are expressed as excitatory units, and play a key physiological role in synaptic function. Although NMDARs are widely expressed in most types of neurons, they play a different role in the cerebellar Purkinje cells (PCs). Utilizing a computational PC model with detailed dendritic morphology, we explored the role of NMDARs at different parts of dendritic branches and regions. We found somatic responses can switch from silent, to simple spikes and complex spikes, depending on specific dendritic branches. Detailed examination of the dendrites regarding their diameters and distance to soma revealed diverse response patterns, yet explain two firing modes, simple and complex spike. Taken together, these results suggest that NMDARs play an important role in controlling excitability sensitivity while taking into account the factor of dendritic properties. Given the complexity of neural morphology varying in cell types, our work suggests that the functional role of NMDARs is not stereotyped but highly interwoven with local properties of neuronal structure.


Assuntos
Dendritos , Receptores de N-Metil-D-Aspartato , Dendritos/fisiologia , Neurônios/fisiologia , Células de Purkinje/fisiologia , Sinapses/fisiologia , Potenciais de Ação/fisiologia
10.
Inorg Chem ; 63(9): 4412-4418, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38381086

RESUMO

Due to the flexible structural tunability and excellent photoelectric performance, hybrid organic-inorganic metal halides (OIMHs) have attracted intensive attention and become a hot topic in the field of materials. It is important and necessary to explore new OIMHs and study their structure-property relationship. In this work, a new lead-free OIMH, (C5N2H14Cl)GeCl3, is synthesized by the combination of hydrothermal and solution methods. This compound features a zero-dimensional structure composed of inorganic [GeCl3]- trigonal pyramids surrounded by isolated Cl- anions and organic (C5N2H14)2+ cations. Preliminary characterization and first-principles calculations are performed to study its basic optical properties. Interestingly, (C5N2H14Cl)GeCl3 shows weak blue emission under ultraviolet excitation, and the intrinsic mechanism is discussed.

11.
Mol Biol Rep ; 51(1): 377, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38427114

RESUMO

BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) exerts neuroprotective effects early in cerebral ischemia/reperfusion (I/R) injury. Intermittent theta-brust stimulation (iTBS), a more time-efficient modality of rTMS, improves the efficiency without at least decreasing the efficacy of the therapy. iTBS elevates cortical excitability, and in recent years it has become increasingly common to apply iTBS to patients in the early post-IS period. However, little is known about the neuroprotective mechanisms of iTBS. Endoplasmic reticulum stress (ERS), and ferroptosis have been shown to be involved in the development of I/R injury. We aimed to investigate the potential regulatory mechanisms by which iTBS attenuates neurological injury after I/R in rats. METHODS: Rats were randomly divided into three groups: sham-operated group, MCAO/R group, and MCAO/R + iTBS group, and were stimulated with iTBS 36 h after undergoing middle cerebral artery occlusion (MCAO) or sham-operated. The expression of ERS, ferroptosis, and apoptosis-related markers was subsequently detected by western blot assays. We also investigated the mechanism by which iTBS attenuates nerve injury after ischemic reperfusion in rats by using the modified Neurological Severity Score (mNSS) and the balance beam test to measure nerve function. RESULTS: iTBS performed early in I/R injury attenuated the levels of ERS, ferroptosis, and apoptosis, and improved neurological function, including mNSS and balance beam experiments. It is suggested that this mode of stimulation reduces the cost per treatment by several times without compromising the efficacy of the treatment and could be a practical and less costly intervention.


Assuntos
Ferroptose , Traumatismo por Reperfusão , Humanos , Ratos , Animais , Estimulação Magnética Transcraniana , Traumatismo por Reperfusão/terapia , Reperfusão , Estresse do Retículo Endoplasmático
12.
J Pediatr Gastroenterol Nutr ; 78(2): 328-338, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38374561

RESUMO

OBJECTIVES: The Starzl Network for Excellence in Pediatric Transplantation identified optimizing immunosuppression (IS) as a priority practice improvement area for patients, families, and providers. We aimed to evaluate associations between clinical characteristics, early IS, and outcomes. METHODS: We analyzed pediatric liver transplant (LT) data from 2013 to 2018 in the United Network for Organ Sharing (UNOS) and the Society of Pediatric Liver Transplantation (SPLIT) registries. RESULTS: We included 2542 LT recipients in UNOS and 1590 in SPLIT. IS choice varied between centers with steroid induction and mycophenolate mofetil (MMF) use each ranging from 0% to 100% across centers. Clinical characteristics associated with early IS choice were inconsistent between the two data sets. T-cell depleting antibody use was associated with improved 1-year graft (hazard ratio [HR] 0.50, 95% confidence interval [CI] 0.34-0.76) and patient (HR 0.40, 95% CI 0.20-0.79) survival in UNOS but decreased 1-year patient survival (HR 4.12, 95% CI 1.31-12.93) and increased acute rejection (HR 1.58, 95% CI 1.07-2.34) in SPLIT. Non-T-cell depleting antibody use was not associated with differential risk of survival nor rejection. MMF use was associated with improved 1-year graft survival (HR 0.73, 95% CI 0.54-0.99) in UNOS only. CONCLUSIONS: Variation exists in center choice of early IS regimen. UNOS and SPLIT data provide conflicting associations between IS and outcomes in multivariable analysis. These results highlight the need for future multicenter collaborative work to identify evidence-based IS best practices.


Assuntos
Transplante de Rim , Transplante de Fígado , Criança , Humanos , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Terapia de Imunossupressão/métodos , Imunossupressores/uso terapêutico , Ácido Micofenólico/uso terapêutico
13.
BMC Cardiovasc Disord ; 24(1): 208, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38615012

RESUMO

BACKGROUND: Obesity and hypertension are major risk factors for cardiovascular diseases that affect millions of people worldwide. Both conditions are associated with chronic low-grade inflammation, which is mediated by adipokines such as adiponectin. Adiponectin is the most abundant adipokine that has a beneficial impact on metabolic and vascular biology, while high serum concentrations are associated with some syndromes. This "adiponectin paradox" still needs to be clarified in obesity-associated hypertension. The aim of this study was to investigate how adiponectin affects blood pressure, inflammation, and metabolic function in obesity hypertension using a Chinese adult case-control study. METHODS: A case-control study that had finished recruiting 153 subjects divided as four characteristic groups. Adiponectin serum levels were tested by ELISA in these subjects among these four characteristic Chinese adult physical examination groups. Waist circumference (WC), body mass index (BMI), systolic blood pressure (SB), diastolic blood pressure (DB), and other clinical laboratory data were collected. Analyzation of correlations between the research index and differences between groups was done by SPSS. RESULTS: Serum adiponectin levels in the| normal healthy group (NH group) were significantly higher than those in the newly diagnosed untreated just-obesity group (JO group), and negatively correlated with the visceral adiposity index. With multiple linear egression analysis, it was found that, for serum adiponectin, gender, serum albumin (ALB), alanine aminotransferase (ALT) and high-density lipoprotein cholesterol (HDLC) were the significant independent correlates, and for SB, age and HDLC were the significant independent correlates, and for DB, alkaline phosphatase (ALP) was the significant independent correlate. The other variables did not reach significance in the model. CONCLUSIONS: Our study reveals that adiponectin's role in obesity-hypertension is multifaceted and is influenced by the systemic metabolic homeostasis signaling axis. In obesity-related hypertension, compensatory effects, adiponectin resistance, and reduced adiponectin clearance from impaired kidneys and liver all contribute to the "adiponectin paradox".


Assuntos
Adiponectina , Hipertensão , Adulto , Humanos , Estudos de Casos e Controles , Hipertensão/diagnóstico , Obesidade/complicações , Obesidade/diagnóstico , HDL-Colesterol , Inflamação , China/epidemiologia
14.
J Chem Phys ; 160(2)2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38197443

RESUMO

The network structure within polymers significantly influences their mechanical properties, including their strength, toughness, and fatigue resistance. All-atom molecular dynamics (AAMD) simulations offer a method to investigate the energy dissipation mechanism within polymers during deformation and fracture; Such an approach is, however, computationally inefficient when used to analyze polymers with complex network structures, such as the common chemically double-networked hydrogels. Alternatively, coarse-grained molecular dynamics (CGMD) models, which reduce the computational degrees of freedom by concentrating a set of adjacent atoms into a coarse-grained bead, can be employed. In CGMD simulations, a coarse-grained force field (CGFF) is a critical factor affecting the simulation accuracy. In this paper, we proposed a data-based method for predicting the CGFF parameters to improve the simulation efficiency of complex cross-linked network in polymers. Here, we utilized a typical chemically double-networked hydrogel as an example. An artificial neural network was selected, and it was trained with the tensile stress-strain data from the CGMD simulations using different CGFF parameters. The CGMD simulations using the predicted CGFF parameters show good agreement with the AAMD simulations and are almost fifty times faster. The data-inspired CGMD model presented here broadens the applicability of molecular dynamics simulations to cross-linked polymers and has the potential to provide insights that will aid the design of polymers with desirable mechanical properties.

15.
J Nanobiotechnology ; 22(1): 214, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689291

RESUMO

Combination of tumor immunotherapy with photothermal therapy (PTT) is a feasible tactic to overcome the drawback of immunotherapy such as poor immune response. Via triggering the immunogenic cells death (ICD), PTT can stimulate the activity of immune cells, but meanwhile, the level of adenosine is elevated via the CD73-induced decomposition of ATP which is overexpressed accompanying with the PTT process, resulting in negative feedback to impair the immune stimulation. Herein, we developed a novel biomimetic photothermal nanodrug to specifically block CD73 for inhibition of adenosine production and more efficient priming of the suppressive immune microenvironments. The nanodrug, named as AptEM@CBA, is constructed by encapsulation of photothermal agent black phosphorus quantum dots (BPQDs) and selective CD73 inhibitor α, ß-Methyleneadenosine 5'-diphosphate (AMPCP) in chitosan nanogels, which are further covered with aptamer AS1411 modified erythrocyte membrane (EM) for biomimetic camouflage. With AS1411 induced active targeting and EM induced long blood circulation time, the enrichment of the nanodrug tumor sites is promoted. The photothermal treatment promotes the maturation of dendritic cells. Meanwhile, the release of AMPCP suppress the adenosine generation via CD73 blockade, alleviating the impairment of adenosine to dendritic cells and suppressing regulatory T cells, synergically stimulate the activity of T cells. The combination of CD73 blockade with PTT, not only suppresses the growth of primary implanted tumors, but also boosts strong antitumor immunity to inhibit the growth of distal tumors, providing good potential for tumor photoimmunotherapy.


Assuntos
5'-Nucleotidase , Difosfato de Adenosina , Adenosina , Imunoterapia , Terapia Fototérmica , Animais , Humanos , Camundongos , 5'-Nucleotidase/antagonistas & inibidores , Adenosina/química , Adenosina/análogos & derivados , Adenosina/farmacologia , Difosfato de Adenosina/análogos & derivados , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Biomimética/métodos , Linhagem Celular Tumoral , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Imunoterapia/métodos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Nanopartículas/química , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Terapia Fototérmica/métodos , Pontos Quânticos/química , Microambiente Tumoral/efeitos dos fármacos , Masculino
16.
J Nanobiotechnology ; 22(1): 165, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600567

RESUMO

As a common musculoskeletal disorder, frozen shoulder is characterized by thickened joint capsule and limited range of motion, affecting 2-5% of the general population and more than 20% of patients with diabetes mellitus. Pathologically, joint capsule fibrosis resulting from fibroblast activation is the key event. The activated fibroblasts are proliferative and contractive, producing excessive collagen. Albeit high prevalence, effective anti-fibrosis modalities, especially fibroblast-targeting therapies, are still lacking. In this study, microRNA-122 was first identified from sequencing data as a potential therapeutic agent to antagonize fibroblast activation. Then, Agomir-122, an analog of microRNA-122, was loaded into poly(lactic-co-glycolic acid) (PLGA) nanoparticles (Agomir-122@NP), a carrier with excellent biocompatibility for the agent delivery. Moreover, relying on the homologous targeting effect, we coated Agomir-122@NP with the cell membrane derived from activated fibroblasts (Agomir-122@MNP), with an attempt to inhibit the proliferation, contraction, and collagen production of abnormally activated fibroblasts. After confirming the targeting effect of Agomir-122@MNP on activated fibroblasts in vitro, we proved that Agomir-122@MNP effectively curtailed fibroblasts activation, ameliorated joint capsule fibrosis, and restored range of motion in mouse models both prophylactically and therapeutically. Overall, an effective targeted delivery method was developed with promising translational value against frozen shoulder.


Assuntos
Bursite , MicroRNAs , Nanopartículas , Camundongos , Animais , Humanos , Fibroblastos/metabolismo , Bursite/tratamento farmacológico , Bursite/metabolismo , Membrana Celular , Fibrose , Colágeno/metabolismo , MicroRNAs/metabolismo
17.
Med Sci Monit ; 30: e943785, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38879751

RESUMO

Stroke is a cerebrovascular disease that impairs blood supply to localized brain tissue regions due to various causes. This leads to ischemic and hypoxic lesions, necrosis of the brain tissue, and a variety of functional disorders. Abnormal cortical activation and functional connectivity occur in the brain after a stroke, but the activation patterns and functional reorganization are not well understood. Rehabilitation interventions can enhance functional recovery in stroke patients. However, clinicians require objective measures to support their practice, as outcome measures for functional recovery are based on scale scores. Furthermore, the most effective rehabilitation measures for treating patients are yet to be investigated. Functional near-infrared spectroscopy (fNIRS) is a non-invasive neuroimaging method that detects changes in cerebral hemodynamics during task performance. It is widely used in neurological research and clinical practice due to its safety, portability, high motion tolerance, and low cost. This paper briefly introduces the imaging principle and the advantages and disadvantages of fNIRS to summarize the application of fNIRS in post-stroke rehabilitation.


Assuntos
Espectroscopia de Luz Próxima ao Infravermelho , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/diagnóstico por imagem , Neuroimagem/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Recuperação de Função Fisiológica/fisiologia
18.
Appl Opt ; 63(12): 3130-3137, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38856457

RESUMO

Numerous applications at the photon-starved regime require a free-space coupling single-photon detector with a large active area, low dark count rate (DCR), and superior time resolutions. Here, we developed a superconducting microstrip single-photon detector (SMSPD), with a large active area of 260 µm in diameter, a DCR of ∼5k c p s, and a low time jitter of ∼171p s, operated at a near-infrared of 1550 nm and a temperature of ∼2.0K. As a demonstration, we applied the detector to a single-pixel galvanometer scanning system and successfully reconstructed the object information in depth and intensity using a time-correlated photon counting technology.

19.
Proc Natl Acad Sci U S A ; 118(12)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33731479

RESUMO

The negatively charged silicon monovacancy [Formula: see text] in 4H silicon carbide (SiC) is a spin-active point defect that has the potential to act as a qubit in solid-state quantum information applications. Photonic crystal cavities (PCCs) can augment the optical emission of the [Formula: see text], yet fine-tuning the defect-cavity interaction remains challenging. We report on two postfabrication processes that result in enhancement of the [Formula: see text] optical emission from our PCCs, an indication of improved coupling between the cavity and ensemble of silicon vacancies. Below-bandgap irradiation at 785-nm and 532-nm wavelengths carried out at times ranging from a few minutes to several hours results in stable enhancement of emission, believed to result from changing the relative ratio of [Formula: see text] ("dark state") to [Formula: see text] ("bright state"). The much faster change effected by 532-nm irradiation may result from cooperative charge-state conversion due to proximal defects. Thermal annealing at 100 °C, carried out over 20 min, also results in emission enhancements and may be explained by the relatively low-activation energy diffusion of carbon interstitials [Formula: see text], subsequently recombining with other defects to create additional [Formula: see text]s. These PCC-enabled experiments reveal insights into defect modifications and interactions within a controlled, designated volume and indicate pathways to improved defect-cavity interactions.

20.
Ecotoxicol Environ Saf ; 275: 116273, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38564861

RESUMO

BACKGROUND: Sarcopenia is characterized by decreased muscle mass and strength, posing threat to quality of life. Air pollutants are increasingly recognized as risk factors for diseases, while the relationship between the two remains to be elucidated. This study investigated whether exposure to ambient air pollution contributes to the development of sarcopenia. METHODS: We employed the data from the UK Biobank with 303,031 eligible participants. Concentrations of PM2·5, NO2, and NOx were estimated. Cox proportional hazard regression models were applied to investigate the associations between pollutants and sarcopenia. RESULTS: 30,766 probable sarcopenia cases was identified during the follow-up. We observed that exposure to PM2.5 (HR, 1.232; 95% CI, 1.053-1.440), NO2 (HR, 1.055; 95% CI, 1.032-1.078) and NOx (HR, 1.016; 95% CI, 1.007-1.026) were all significantly associated with increased risk for probable sarcopenia for each 10 µg/m3 increase in pollutant concentration. In comparison with individuals in the lowest quartiles of exposure, those in the upper quartiles had significantly increased risk of probable sarcopenia. Sarcopenia-related factors, e.g., reduced lean muscle mass, diminished walking pace, and elevated muscle fat infiltration ratio, also exhibited positive associations with exposure to ambient air pollution. On the contrary, high level physical activity significantly mitigated the influence of air pollutants on the development of probable sarcopenia. CONCLUSIONS: Air pollution exposure elevated the risk of developing sarcopenia and related manifestations in a dose-dependent manner, while physical activity maintained protective under this circumstance. Efforts should be made to control air pollution and emphasize the importance of physical activity for skeletal muscle health under this circumstance.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Sarcopenia , Humanos , Estudos Prospectivos , Dióxido de Nitrogênio , Sarcopenia/etiologia , Sarcopenia/induzido quimicamente , Qualidade de Vida , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Poluentes Atmosféricos/análise , Material Particulado/toxicidade , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise
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