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1.
PLoS Biol ; 20(5): e3001633, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35622868

RESUMO

The rate of adaptive evolution depends on the rate at which beneficial mutations are introduced into a population and the fitness effects of those mutations. The rate of beneficial mutations and their expected fitness effects is often difficult to empirically quantify. As these 2 parameters determine the pace of evolutionary change in a population, the dynamics of adaptive evolution may enable inference of their values. Copy number variants (CNVs) are a pervasive source of heritable variation that can facilitate rapid adaptive evolution. Previously, we developed a locus-specific fluorescent CNV reporter to quantify CNV dynamics in evolving populations maintained in nutrient-limiting conditions using chemostats. Here, we use CNV adaptation dynamics to estimate the rate at which beneficial CNVs are introduced through de novo mutation and their fitness effects using simulation-based likelihood-free inference approaches. We tested the suitability of 2 evolutionary models: a standard Wright-Fisher model and a chemostat model. We evaluated 2 likelihood-free inference algorithms: the well-established Approximate Bayesian Computation with Sequential Monte Carlo (ABC-SMC) algorithm, and the recently developed Neural Posterior Estimation (NPE) algorithm, which applies an artificial neural network to directly estimate the posterior distribution. By systematically evaluating the suitability of different inference methods and models, we show that NPE has several advantages over ABC-SMC and that a Wright-Fisher evolutionary model suffices in most cases. Using our validated inference framework, we estimate the CNV formation rate at the GAP1 locus in the yeast Saccharomyces cerevisiae to be 10-4.7 to 10-4 CNVs per cell division and a fitness coefficient of 0.04 to 0.1 per generation for GAP1 CNVs in glutamine-limited chemostats. We experimentally validated our inference-based estimates using 2 distinct experimental methods-barcode lineage tracking and pairwise fitness assays-which provide independent confirmation of the accuracy of our approach. Our results are consistent with a beneficial CNV supply rate that is 10-fold greater than the estimated rates of beneficial single-nucleotide mutations, explaining the outsized importance of CNVs in rapid adaptive evolution. More generally, our study demonstrates the utility of novel neural network-based likelihood-free inference methods for inferring the rates and effects of evolutionary processes from empirical data with possible applications ranging from tumor to viral evolution.


Assuntos
Aclimatação , Redes Neurais de Computação , Algoritmos , Teorema de Bayes , Simulação por Computador , Saccharomyces cerevisiae/genética
2.
Mol Cell ; 65(1): 142-153, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-27989436

RESUMO

Gene expression burdens cells by consuming resources and energy. While numerous studies have investigated regulation of expression level, little is known about gene design elements that govern expression costs. Here, we ask how cells minimize production costs while maintaining a given protein expression level and whether there are gene architectures that optimize this process. We measured fitness of ∼14,000 E. coli strains, each expressing a reporter gene with a unique 5' architecture. By comparing cost-effective and ineffective architectures, we found that cost per protein molecule could be minimized by lowering transcription levels, regulating translation speeds, and utilizing amino acids that are cheap to synthesize and that are less hydrophobic. We then examined natural E. coli genes and found that highly expressed genes have evolved more forcefully to minimize costs associated with their expression. Our study thus elucidates gene design elements that improve the economy of protein expression in natural and heterologous systems.


Assuntos
Aminoácidos/metabolismo , Metabolismo Energético , Proteínas de Escherichia coli/biossíntese , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica , Aptidão Genética , Transcrição Gênica , Interações Hidrofóbicas e Hidrofílicas , Biossíntese de Proteínas , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Fatores de Tempo
3.
J Transl Med ; 22(1): 604, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951906

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) is a recurrent, heterogeneous, and invasive form of breast cancer. The treatment of TNBC patients with paclitaxel and fluorouracil in a sequential manner has shown promising outcomes. However, it is challenging to deliver these chemotherapeutic agents sequentially to TNBC tumors. We aim to explore a precision therapy strategy for TNBC through the sequential delivery of paclitaxel and fluorouracil. METHODS: We developed a dual chemo-loaded aptamer with redox-sensitive caged paclitaxel for rapid release and non-cleavable caged fluorouracil for slow release. The binding affinity to the target protein was validated using Enzyme-linked oligonucleotide assays and Surface plasmon resonance assays. The targeting and internalization abilities into tumors were confirmed using Flow cytometry assays and Confocal microscopy assays. The inhibitory effects on TNBC progression were evaluated by pharmacological studies in vitro and in vivo. RESULTS: Various redox-responsive aptamer-paclitaxel conjugates were synthesized. Among them, AS1411-paclitaxel conjugate with a thioether linker (ASP) exhibited high anti-proliferation ability against TNBC cells, and its targeting ability was further improved through fluorouracil modification. The fluorouracil modified AS1411-paclitaxel conjugate with a thioether linker (FASP) exhibited effective targeting of TNBC cells and significantly improved the inhibitory effects on TNBC progression in vitro and in vivo. CONCLUSIONS: This study successfully developed fluorouracil-modified AS1411-paclitaxel conjugates with a thioether linker for targeted combination chemotherapy in TNBC. These conjugates demonstrated efficient recognition of TNBC cells, enabling targeted delivery and controlled release of paclitaxel and fluorouracil. This approach resulted in synergistic antitumor effects and reduced toxicity in vivo. However, challenges related to stability, immunogenicity, and scalability need to be further investigated for future translational applications.


Assuntos
Aptâmeros de Nucleotídeos , Preparações de Ação Retardada , Liberação Controlada de Fármacos , Fluoruracila , Nucleolina , Paclitaxel , Fosfoproteínas , Proteínas de Ligação a RNA , Neoplasias de Mama Triplo Negativas , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Aptâmeros de Nucleotídeos/farmacologia , Aptâmeros de Nucleotídeos/química , Humanos , Paclitaxel/uso terapêutico , Paclitaxel/farmacologia , Linhagem Celular Tumoral , Animais , Feminino , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Proteínas de Ligação a RNA/metabolismo , Fosfoproteínas/metabolismo , Oligodesoxirribonucleotídeos/farmacologia , Oligodesoxirribonucleotídeos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto , Proliferação de Células/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Camundongos Endogâmicos BALB C
4.
Lupus ; : 9612033241266988, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39037598

RESUMO

OBJECTIVES: Emerging evidence indicate that long noncoding RNAs (lncRNAs) may play an important role in the pathogenesis of systemic lupus erythematosus (SLE) however, the contribution of lncRNAs to SLE remains largely unclear. Our study aimed to explore the lncRNA expression profiles in peripheral blood mononuclear cells (PBMCs) from SLE patients. METHODS: LncRNA sequencing was used to detect differentially expressed genes in PBMCs from 5 SLE-MIX samples and 3 healthy controls (HC)-MIX samples, and the expression of selected lncRNAs was further verified by real-time quantitative polymerase chain reaction (RT‒qPCR). The correlation of lncRNA expression with laboratory indicators as well the SLE disease activity index 2000 (SLEDAI‒2K) score from 72 SLE patients was assessed by Spearman's test. The association between lncRNA ENST00000597482 and organ involvement in SLE patients was determined by the Mann‒Whitney U test. Moreover, lymphocyte subsets in peripheral blood from SLE patients were measured by flow cytometry. In addition, the diagnostic value of lncRNAs in predicting SLE was evaluated by receiver operating characteristic (ROC) curve analysis. RESULTS: The lncRNA expression profiles demonstrated 218 differentially expressed lncRNAs, including 121 upregulated genes and 97 downregulated genes, in PBMCs from SLE patients compared to HCs. Among the 10 candidate genes selected, only lncRNA ENST00000597482, which was lower in SLE PBMCs than in HCs, was consistent with the sequencing results. LncRNA ENST00000597482 expression was negatively correlated with SLEDAI-2K score and the titres of ANA antibodies and anti-double-stranded DNA (anti-dsDNA) antibodies. Of note, SLE patients with lower expression of lncRNA ENST00000597482 were prone to develop organ involvement. Furthermore, lncRNA ENST00000597482 exhibited potential diagnostic value in differentiating SLE patients from HCs. CONCLUSIONS: LncRNA ENST00000597482 expression was lower in PBMCs from SLE patients than HCs and was negatively correlated with the SLEDAI-2K score and autoantibody titres. In addition, lncRNA ENST00000597482 could act as a novel biomarker for disease activity and diagnosis of SLE.

5.
Lupus ; 33(6): 587-597, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38506324

RESUMO

OBJECTIVE: Human gamma-delta T cells (γδ-T cells) play crucial roles in both innate and adaptive immune responses. However, much less is known about the immune status of γδT cells in systemic lupus erythematosus (SLE) patients. The objective of this study was to explore potential relationships between the frequency of γδ-T-cell subpopulations and disease activity, autoantibody titres and renal involvement in patients with SLE. METHODS: Circulating γδ-T cells and their subsets (Vδ1+ T cells, Vδ2+ T cells and γδ-T-cell subpopulations defined by expression of surface receptors, including NKG2D, NKp30, NKp46 and PD-1), were identified via flow cytometry. Sixty active SLE patients were selected, including 41 new-onset and 19 relapsing cases. One hundred healthy controls (HCs) were enrolled as the control group. Percentages of these cell subsets in SLE patients and HCs and their relationships with disease activity were analysed. Twenty-two of the 41 new-onset SLE patients were assessed before and after treatment. Changes in the frequencies of these cell subsets and their relationships with renal involvement were also analysed. RESULTS: Compared with that in HCs, the percentage of total γδ-T cells among CD3+ T cells in SLE patients was significantly lower. An imbalance in the proportions of Vδ1+ and Vδ2+ T cells among γδ-T cells was observed. The proportion of Vδ1+ T cells among γδ-T cells was significantly greater in SLE patients than in HCs, while the proportion of Vδ2+ T cells was significantly lower. Expression levels of PD-1, NKG2D, NKp30 and NKp46 in Vδ1+ T cells and Vδ2+ T cells from SLE patients were generally significantly increased, except for expression of NKG2D in Vδ2+ T cells. Moreover, Vδ2+ T cells, Vδ1+ T cells and Vδ1+PD-1+ T cells were associated with disease activity, and an increase in Vδ2+ T-cell frequency and a decrease in PD-1 expression by γδ-T cells might be associated with effective treatment. Interestingly, our results indicated that Vδ2+ T cells and their Vδ2+NKp30+ T-cell subpopulation might be associated with renal involvement in SLE. CONCLUSION: A broad range of anomalies in the proportions of γδ-T-cell subsets and γδ-T cells in SLE patients may be involved in the pathogenesis of SLE. There is a strong association between Vδ2+ T cells and their Vδ2+NKp30+ T-cell subpopulation and LN occurrence. Our results indicate that γδ-T cells and their subpopulations might be key players in disease immunopathology and renal involvement in SLE.


Assuntos
Lúpus Eritematoso Sistêmico , Receptores de Antígenos de Linfócitos T gama-delta , Humanos , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Subpopulações de Linfócitos T , Fenótipo
6.
BMC Cardiovasc Disord ; 24(1): 11, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166688

RESUMO

BACKGROUND: Endothelial dysfunction is characterized by an imbalance between endothelium-derived vasodilatory and vasoconstrictive effects and may play an important role in the development of heart failure. An increasing number of studies have shown that endothelial-derived NO-mediated vasodilation is attenuated in heart failure patients. However, the role of endothelin-1 (ET-1) in heart failure remains controversial due to its different receptors including ET-1 receptor type A (ETAR) and ET-1 receptor type B (ETBR). The aim of this study was to determine whether ET-1 and its receptors are activated and to explore the role of ETAR and ETBR in heart failure induced by myocarditis. METHODS: We constructed an animal model of experimental autoimmune myocarditis (EAM) with porcine cardiac myosin. Twenty rats were randomized to the control group (3 weeks, n = 5), the extended control group (8 weeks, n = 5), the EAM group (3 weeks, n = 5), the extended EAM group (8 weeks, n = 5). HE staining was used to detect myocardial inflammatory infiltration and the myocarditis score, Masson's trichrome staining was used to assess myocardial fibrosis, echocardiography was used to evaluate cardiac function, ELISA was used to detect serum NT-proBNP and ET-1 concentrations, and immunohistochemistry and western blotting were used to detect ETAR and ETBR expression in myocardial tissue of EAM-induced heart failure. Subsequently, a model of myocardial inflammatory injury in vitro was constructed to explore the role of ETAR and ETBR in EAM-induced heart failure. RESULTS: EAM rats tended to reach peak inflammation after 3 weeks of immunization and developed stable chronic heart failure at 8 weeks after immunization. LVEDd and LVEDs were significantly increased in the EAM group compared to the control group at 3 weeks and 8 weeks after immunization while EF and FS were significantly reduced. Serum NT-proBNP concentrations in EAM (both 3 weeks and 8 weeks) were elevated. Therefore, EAM can induce acute and chronic heart failure due to myocardial inflammatory injury. Serum ET-1 concentration and myocardial ETAR and ETBR protein were significantly increased in EAM-induced heart failure in vivo. Consistent with the results of the experiments in vivo, ETAR and ETBR protein expression levels were significantly increased in the myocardial inflammatory injury model in vitro. Moreover, ETAR gene silencing inhibited inflammatory cytokine TNF-α and IL-1ß levels, while ETBR gene silencing improved TNF-α and IL-1ß levels. CONCLUSIONS: ET-1, ETAR, and ETBR were activated in both EAM-induced acute heart failure and chronic heart failure. ETAR may positively regulate EAM-induced heart failure by promoting myocardial inflammatory injury, whereas ETBR negatively regulates EAM-induced heart failure by alleviating myocardial inflammatory injury.


Assuntos
Doenças Autoimunes , Insuficiência Cardíaca , Traumatismos Cardíacos , Miocardite , Receptor de Endotelina A , Receptor de Endotelina B , Animais , Ratos , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/metabolismo , Miocardite/induzido quimicamente , Miocárdio/metabolismo , Suínos , Fator de Necrose Tumoral alfa/metabolismo , Receptor de Endotelina A/metabolismo , Receptor de Endotelina B/metabolismo
8.
BMC Genomics ; 24(1): 246, 2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37149606

RESUMO

BACKGROUND: Genetic barcoding provides a high-throughput way to simultaneously track the frequencies of large numbers of competing and evolving microbial lineages. However making inferences about the nature of the evolution that is taking place remains a difficult task. RESULTS: Here we describe an algorithm for the inference of fitness effects and establishment times of beneficial mutations from barcode sequencing data, which builds upon a Bayesian inference method by enforcing self-consistency between the population mean fitness and the individual effects of mutations within lineages. By testing our inference method on a simulation of 40,000 barcoded lineages evolving in serial batch culture, we find that this new method outperforms its predecessor, identifying more adaptive mutations and more accurately inferring their mutational parameters. CONCLUSION: Our new algorithm is particularly suited to inference of mutational parameters when read depth is low. We have made Python code for our serial dilution evolution simulations, as well as both the old and new inference methods, available on GitHub ( https://github.com/FangfeiLi05/FitMut2 ), in the hope that it can find broader use by the microbial evolution community.


Assuntos
Algoritmos , Teorema de Bayes , Simulação por Computador , Mutação
9.
J Mol Evol ; 91(3): 334-344, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36877292

RESUMO

The fitness of a genotype is defined as its lifetime reproductive success, with fitness itself being a composite trait likely dependent on many underlying phenotypes. Measuring fitness is important for understanding how alteration of different cellular components affects a cell's ability to reproduce. Here, we describe an improved approach, implemented in Python, for estimating fitness in high throughput via pooled competition assays.


Assuntos
Reprodução , Software , Fenótipo , Genótipo , Aptidão Genética
10.
Eur Radiol ; 33(9): 6134-6144, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37014408

RESUMO

OBJECTIVES: To evaluate the dynamic evolution process of overall brain health in liver transplantation (LT) recipients, we employed a deep learning-based neuroanatomic biomarker to measure longitudinal changes of brain structural patterns before and 1, 3, and 6 months after surgery. METHODS: Because of the ability to capture patterns across all voxels from a brain scan, the brain age prediction method was adopted. We constructed a 3D-CNN model through T1-weighted MRI of 3609 healthy individuals from 8 public datasets and further applied it to a local dataset of 60 LT recipients and 134 controls. The predicted age difference (PAD) was calculated to estimate brain changes before and after LT, and the network occlusion sensitivity analysis was used to determine the importance of each network in age prediction. RESULTS: The PAD of patients with cirrhosis increased markedly at baseline (+ 5.74 years) and continued to increase within one month after LT (+ 9.18 years). After that, the brain age began to decrease gradually, but it was still higher than the chronological age. The PAD values of the OHE subgroup were higher than those of the no-OHE, and the discrepancy was more obvious at 1-month post-LT. High-level cognition-related networks were more important in predicting the brain age of patients with cirrhosis at baseline, while the importance of primary sensory networks increased temporarily within 6-month post-LT. CONCLUSIONS: The brain structural patterns of LT recipients showed inverted U-shaped dynamic change in the early stage after transplantation, and the change in primary sensory networks may be the main contributor. KEY POINTS: • The recipients' brain structural pattern showed an inverted U-shaped dynamic change after LT. • The patients' brain aging aggravated within 1 month after surgery, and the subset of patients with a history of OHE was particularly affected. • The change of primary sensory networks is the main contributor to the change in brain structural patterns.


Assuntos
Encefalopatia Hepática , Transplante de Fígado , Humanos , Estudos Longitudinais , Encefalopatia Hepática/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Cirrose Hepática/patologia , Fibrose
11.
Phys Chem Chem Phys ; 25(38): 26145-26151, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37740334

RESUMO

Titanium disulfide (TiS2) has drawn considerable attention in materials, physics, and chemistry thanks to its potential applications in batteries, supercapatteries and thermoelectric devices. However, the simplified and controlled synthesis of high-quality TiS2 remains a great challenge. In this study, a straightforward widely accessible approach to the one-step chemical vapor transport (CVT) process is presented. Meanwhile, combining high-pressure (HP) Raman spectroscopy measurements and first-principles calculations, the pressure-induced phase transition of TiS2 from P3̄m1 phase (phase I) to C2/m phase (phase II) at 16.0 GPa and then to P6̄2m phase (phase III) at 32.4 GPa was disclosed. The discovery of HP being within the Weyl semi-metallic phase represents a significant advancement towards understanding the electronic topological states, discovering new physical phenomena, developing new electronic devices, and gaining insight into the properties of elementary particles.

12.
J Korean Med Sci ; 38(8): e55, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36852851

RESUMO

BACKGROUND: The emergence of the severe acute respiratory syndrome coronavirus 2 omicron variant has been triggering the new wave of coronavirus disease 2019 (COVID-19) globally. However, the risk factors and outcomes for radiological abnormalities in the early convalescent stage (1 month after diagnosis) of omicron infected patients are still unknown. METHODS: Patients were retrospectively enrolled if they were admitted to the hospital due to COVID-19. The chest computed tomography (CT) images and clinical data obtained at baseline (at the time of the first CT image that showed abnormalities after diagnosis) and 1 month after diagnosis were longitudinally analyzed. Uni-/multi-variable logistic regression tests were performed to explore independent risk factors for radiological abnormalities at baseline and residual pulmonary abnormalities after 1 month. RESULTS: We assessed 316 COVID-19 patients, including 47% with radiological abnormalities at baseline and 23% with residual pulmonary abnormalities at 1-month follow-up. In a multivariate regression analysis, age ≥ 50 years, body mass index ≥ 23.87, days after vaccination ≥ 81 days, lymphocyte count ≤ 1.21 × 10-9/L, interleukin-6 (IL-6) ≥ 10.05 pg/mL and IgG ≤ 14.140 S/CO were independent risk factors for CT abnormalities at baseline. The age ≥ 47 years, presence of interlobular septal thickening and IL-6 ≥ 5.85 pg/mL were the independent risk factors for residual pulmonary abnormalities at 1-month follow-up. For residual abnormalities group, the patients with less consolidations and more parenchymal bands at baseline could progress on CT score after 1 month. There were no significant changes in the number of involved lung lobes and total CT score during the early convalescent stage. CONCLUSION: The higher IL-6 level was a common independent risk factor for CT abnormalities at baseline and residual pulmonary abnormalities at 1-month follow-up. There were no obvious radiographic changes during the early convalescent stage in patients with residual pulmonary abnormalities.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Pessoa de Meia-Idade , Seguimentos , Estudos Retrospectivos , Convalescença , Interleucina-6
13.
Int J Mol Sci ; 24(17)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37686343

RESUMO

The members of the cytokine interleukin 17 (IL-17) family, along with their receptors (IL-17R), are vital players in a range of inflammatory diseases and cancer. Although generally regarded as proinflammatory, the effects they exhibit on cancer progression are a double-edged sword, with both antitumor and protumor activities being discovered. There is growing evidence that the IL-17 signaling pathways have significant impacts on the tumor microenvironment (TME), immune response, and inflammation in various types of cancer, including pancreatic cancer. However, the detailed mechanistic functions of the IL-17/IL-17R families in pancreatic cancer were rarely systematically elucidated. This review considers the role of the IL-17/IL-17R families in inflammation and tumor immunity and elaborates on the mechanistic functions and correlations of these members with pathogenesis, progression, and chemoresistance in pancreatic cancer. By summarizing the advanced findings on the role of IL-17/IL17R family members and IL-17 signaling pathways at the molecular level, cellular level, and disease level in pancreatic cancer, this review provides an in-depth discussion on the potential of IL-17/IL-17R as prognostic markers and therapeutic targets in pancreatic cancer.


Assuntos
Interleucina-17 , Neoplasias Pancreáticas , Humanos , Citocinas , Inflamação , Microambiente Tumoral , Neoplasias Pancreáticas
14.
Cell Mol Neurobiol ; 42(6): 1897-1908, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33712886

RESUMO

Neurons in the penumbra (the area surrounding ischemic tissue that consists of still viable tissue but with reduced blood flow and oxygen transport) may be rescued following stroke if adequate perfusion is restored in time. It has been speculated that post-stroke angiogenesis in the penumbra can reduce damage caused by ischemia. However, the mechanism for neovasculature formation in the brain remains unclear and vascular-targeted therapies for brain ischemia remain suboptimal. Here, we show that VEGFR1 was highly upregulated in pericytes after stroke. Knockdown of VEGFR1 in pericytes led to increased infarct area and compromised post-ischemia vessel formation. Furthermore, in vitro studies confirmed a critical role for pericyte-derived VEGFR1 in both endothelial tube formation and pericyte migration. Interestingly, our results show that pericyte-derived VEGFR1 has opposite effects on Akt activity in endothelial cells and pericytes. Collectively, these results indicate that pericyte-specific expression of VEGFR1 modulates ischemia-induced vessel formation and vascular integrity in the brain.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Circulação Cerebrovascular/fisiologia , Células Endoteliais/metabolismo , Humanos , Isquemia/metabolismo , Perfusão , Pericitos , Acidente Vascular Cerebral/metabolismo
15.
Crit Rev Food Sci Nutr ; : 1-22, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36469643

RESUMO

Traditional processing methods can no longer meet the demands of consumers for high-quality muscle food. As a green and non-thermal processing technology, ultrasound has the advantage of improving processing efficiency and reducing processing costs. Of these, the positive effect of power ultrasound in the processing of muscle foods is noticeable. Based on the action mechanism of ultrasound, the factors affecting the action of ultrasound are analyzed. On this basis, the effect of ultrasound technology on muscle food quality and its action mechanism and application status in processing operations (freezing-thawing, tenderization, marination, sterilization, drying, and extraction) is discussed. The transient and steady-state effects, mechanical effects, thermal effects, and chemical effects can have an impact on processing operations through complex correlations, such as improving the efficiency of mass and heat transfer. Ultrasound technology has been proven to be valuable in muscle food processing, but inappropriate ultrasound treatment can also have adverse effects on muscle foods. In the future, kinetic models are expected to be an effective tool for investigating the application effects of ultrasound in food processing. Additionally, the combination with other processing technologies can facilitate their intensive application on an industrial level to overcome the disadvantages of using ultrasound technology alone.

16.
Stroke ; 52(3): 811-820, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33567874

RESUMO

BACKGROUND AND PURPOSE: This study aimed to analyze the impact of baseline posterior circulation Acute Stroke Prognosis Early Computed Tomography Score (pc-ASPECTS) on the efficacy and safety of endovascular therapy (EVT) for patients with acute basilar artery occlusion. METHODS: The BASILAR was a nationwide prospective registry of consecutive patients with a symptomatic and radiologically confirmed acute basilar artery occlusion within 24 hours of symptom onset. We estimated the effect of standard medical therapy alone (SMT group) versus SMT plus EVT (EVT group) for patients with documented pc-ASPECTS on noncontrast CT, both as a categorical (0-4 versus 5-7 versus 8-10) and as a continuous variable. The primary outcomes included favorable functional outcomes (modified Rankin Scale ≤3) at 90 days and mortality within 90 days. RESULTS: In total, 823 cases were included: 468 with pc-ASPECTS 8 to 10 (SMT: 71; EVT: 397), 317 with pc-ASPECTS 5 to 7 (SMT: 85; EVT: 232), and 38 with pc-ASPECTS 0 to 4 (SMT: 13; EVT: 25). EVT was associated with higher rate of favorable outcomes (adjusted relative risk with 95% CI, 4.35 [1.30-14.48] and 3.20 [1.68-6.09]; respectively) and lower mortality (60.8% versus 77.6%, P=0.005 and 35.0% versus 66.2%, P<0.001; respectively) than SMT in the pc-ASPECTS 5 to 7 and 8 to 10 subgroups. Continuous benefit curves also showed the superior efficacy and safety of EVT over SMT in patients with pc-ASPECTS ≥5. Furthermore, the prognostic effect of onset to puncture time on favorable outcome with EVT was not significant after adjustment for pc-ASPECTS (adjusted odds ratio, 0.98 [95% CI, 0.94-1.02]). CONCLUSIONS: Patients of basilar artery occlusion with pc-ASPECTS ≥5 could benefit from EVT. The baseline pc-ASPECTS appears more important for decision making and predicting prognosis than time to EVT. Registration: URL: http://www.chictr.org.cn. Unique identifier: ChiCTR1800014759.


Assuntos
Artéria Basilar/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Idoso , Arteriopatias Oclusivas/complicações , Procedimentos Endovasculares/métodos , Humanos , Pessoa de Meia-Idade , Variações Dependentes do Observador , Prognóstico , Estudos Prospectivos , Sistema de Registros , Trombectomia/métodos , Resultado do Tratamento , Insuficiência Vertebrobasilar/complicações
17.
Phys Rev Lett ; 127(15): 157002, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34678001

RESUMO

The combination of electride state and superconductivity within the same compound, e.g., [Ca_{24}Al_{28}O_{6}]^{4+}(4e^{-}), opens up a new category of conventional superconductors. However, neither the underlying causations to explain superconducting behaviors nor effects of interstitial quasiatoms (ISQs) on superconductivity remain unclear. Here we have designed an efficient and resource-saving method to identify superconducting electrides only by chemical compositions and bonding characteristics. A representative superconducting electride Li_{6}C with a noteworthy T_{c} of 10 K below 1 Mbar among the known binary electrides has been revealed. Our first-principles studies unveil that the anomalous sp-hybridized cage-state ISQs, as a guest in Li_{6}C, exhibit unexpected ionic and covalent bonds, which act as a chemical precompression to lower dynamically stable pressure. More importantly, we uncover that, contrary to common expectations, the high T_{c} is attributed to the strong electron-phonon coupling derived from the synergy of interatomic coupling effect, phonon softening caused by Fermi surface nesting, and phonon-coupled bands, which are mainly dominated by host sp-hybridized electrons, rather than the ISQs. Our present results elucidate a new superconducting mechanism of electrides and shed light on the way for seeking a high-T_{c} superconductor at lower pressures in cage-state electrides.

18.
BMC Neurol ; 21(1): 104, 2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33685396

RESUMO

BACKGROUND: Clopidogrel is an antiplatelet drug used in the treatment of ischemic stroke. Safety and efficacy of clopidogrel has been confirmed in CAPRIE, PRoFESS trials. However, these studies focused on patients aged less than 75 years. CYP2C19 polymorphisms resulted in individual differences in clopidogrel response. Our objective was to determine whether elderly stroke patients aged over 75 years would benefit from CYP2C19-genotype-guided strategy for the secondary prevention of stroke. METHODS: A retrospective analysis of patients aged 75 years or older with non-cardiogenic stroke who received 75 mg clopidogrel was performed. CYP2C19 genotype-guided group included noncarriers of CYP2C19*2 or CYP2C19*3 loss-of-function alleles (LoFA) and compared against the non-genotype-guided group which may carriers CYP2C19 LoFA or not. The primary endpoints were composite of stroke and myocardial infarction at 24 months' follow-up. RESULTS: Two hundred one patients were included: 99 in the genotype-guided group and 102 in the non-genotype-guided group. Kaplan-Meier(KM)analysis showed that CYP2C19 gene polymorphism was associated with the rate of the primary endpoints (P = 0.0031). The primary endpoints occurred in 13 patients (13.1%) in the genotype-guided group and in 30 patients (29.4%) in the non-genotype-guided group (hazard ratio(HR), 0.39; 95% confidence interval(CI), 0.20 to 0.75; p = 0.004). Cox regression analysis showed that CYP2C19 genotype-guided strategy was a protective factor for the primary endpoints (HR, 0.39; 95% CI:0.20 to 0.74, P = 0.004). CONCLUSION: The CYP2C19 genotype-guided strategy could reduce the occurrence of composite of stroke and myocardial infarction compared to a non-genotype-guided strategy for non-cardiogenic stroke patients aged 75 years or older who received clopidogrel.


Assuntos
Clopidogrel/uso terapêutico , Citocromo P-450 CYP2C19/genética , AVC Isquêmico/prevenção & controle , Inibidores da Agregação Plaquetária/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Feminino , Genótipo , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Estudos Retrospectivos , Prevenção Secundária/métodos
19.
Phys Chem Chem Phys ; 23(20): 11709-11716, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-33982049

RESUMO

Pressure has been considered as an effective technique to modulate the structural, electronic, and optical properties of transition metal dichalcogenide (TMDs) materials. Here, by performing in situ high pressure Raman, photoluminescence (PL) and absorption measurements, we systematically investigated the vibrational and electronic properties evolution of monolayer MoSe2 grown on a SiO2/Si substrate under high pressure. When the pressure increased up to 4.84 GPa, an unexpected phonon mode at 367 cm-1 appeared, which was identified as the Raman-inactive A2'' mode and was activated under high pressure. Combined with the analysis of absorption spectroscopy, this phenomenon can be attributed to the pressure-induced wrinkle and near-resonance effects in compressed monolayer MoSe2. Subsequently, A1' split into two peaks after 7.44 GPa, providing further distinct evidence for the pressure-induced wrinkle effect in compressed monolayer MoSe2. Moreover, this wrinkle effect can also lead to a rapid quenching of photoluminescence in monolayer MoSe2. These results suggest that the substrate plays an important role in determining the vibrational and electronic properties of compressed monolayer MoSe2, and can provide valuable information on the electronic and optoelectronic applications of monolayer MoSe2 under extreme conditions.

20.
Med Sci Monit ; 26: e925583, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32574155

RESUMO

BACKGROUND The clinical challenges of triple-negative breast cancer (TNBC) includes the lack of targeted therapy and chemoresistance. TNBC has relatively high PD-L1 expression, and PD-L1 antibody in combination with nab-paclitaxel has been approved by FDA for TNBC treatment. Aptamers, also termed chemical antibody, are widely used in targeted drug delivery. The present study aimed to select a DNA aptamer that could specifically bind and deliver drugs to TNBC cells. MATERIAL AND METHODS An innovative loss-gain cell-SELEX strategy was used to select DNA aptamer for PD-L1 protein. Construction of PD-L1 knock-out and over-expression MDA-MB-231 cell lines were conducted through transfection and confirmed by western blot and flow cytometry. Confocal microscopy and flow cytometry were used to analyze the binding ability of aptamer with TNBC cells. The cytotoxicity of aptamer-paclitaxel complex against TNBC cells was evaluated by Cell Counting Kit-8 assay. The reactivation of the T cell function by aptamer was measured by IL-2 enzyme-linked immunosorbent assay after T cells co-cultured with tumor cells. RESULTS In this work, using an innovative loss-gain cell-SELEX strategy, we screened a PD-L1-targeting aptamer. PD-L1 aptamer selectively bound to PD-L1 over-expressed TNBC cells with a dissociation constant in the nanomolar range. PD-L1 aptamer could also inhibit PD-1/PD-L1 interaction and restore the function of T cells. Moreover, we developed a PD-L1 aptamer-paclitaxel conjugate which showed improved cellular uptake and anti-proliferation efficacy in PD-L1 over-expressed TNBC cells. CONCLUSIONS In summary, these findings suggest that the selected PD-L1 aptamer might have potential implication in immune modulation and targeted therapy against TNBC.


Assuntos
Aptâmeros de Peptídeos/farmacologia , Antígeno B7-H1/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Anticorpos/uso terapêutico , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Feminino , Humanos , Paclitaxel/farmacologia , Receptor de Morte Celular Programada 1/metabolismo , Técnica de Seleção de Aptâmeros/métodos
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