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1.
Opt Express ; 32(7): 11849-11862, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571023

RESUMO

A novel mid-infrared methane remote sensor integrated on a movable platform based on a 3.291-µm interband cascade laser (ICL) and wavelength modulation spectroscopy (WMS) is proposed. A transmitting-receiving coaxial, visualized optical layout is employed to minimize laser energy loss. Using a hollow retro-reflector remotely deployed as a cooperative target, the atmospheric average methane concentration over a 100-meter optical range is measured with high sensitivity. A deep neural network (DNN) filter is used for second harmonic (2f) signal denoising to compensate for the performance shortcomings of conventional filtering. Allan deviation analysis indicated that after applying the DNN filter, the limit of detection (LOD) of methane was 86.62 ppb with an average time of 1 s, decreasing to 12.03 ppb with an average time of 229 s, which is a significant promotion compared to similar work reported. The high sensitivity and stability of the proposed sensor are shown through a 24-hour continuous monitoring experiment of atmospheric methane conducted outdoors, providing a new solution for high-sensitivity remote sensing of atmospheric methane.

2.
Opt Express ; 32(7): 10962-10978, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38570957

RESUMO

We propose a novel methane leakage rate remote sensor that combines a single-photon avalanche diode detector with a near-infrared 1653.7 nm low-power laser. The proposed M sequence and triangle wave signal modulation method simultaneously realizes the detection of methane leakage and target point clouds. Innovatively, the sensor's methane concentration and leakage rate quantification ability were simulated by combining the Gaussian plume diffusion model and the Risley prism. The effects of the prism rotation ratio, wind speed, leakage rate, atmospheric stability (AS), target reflectivity, signal averaging period, and concentration spatial interpolation method on leakage rate are discussed. When plume methane concentrations reduce from 10,000 to 500 ppm·m, the relative concentration bias rise from 1% to 30%, the absolute concentration bias is approximately 100 ppm·m. Two spatial concentration interpolation methods introduced leakage rate bias ranging from 6%-25%. For a low AS, the leakage rate bias under the cubic interpolation method was small (approximately 1.6%). In addition, when the initial leakage rate increased from 100 to 1,000 mg/s, the leakage rate bias was approximately 20% smaller.

3.
J Environ Manage ; 347: 119113, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37769471

RESUMO

Insights into COVID-19 antivirals' environmental fate and ecological risk are urgently required due to their increasing concentrations in aquatic environments, which have rarely been studied. Herein, we first investigated the photochemical transformation and the resulting alterations in toxicity of arbidol, an antiviral drug with relatively higher toxicity. The photolysis of arbidol was rapid with a rate constant of 0.106 min-1 due to its superior ultraviolet light absorption, in which the direct photolysis was predominated with a contribution of 91.5%. Despite its substantial photolysis, only 14.45% of arbidol was mineralized after 100 min, implying that arbidol and its products might have a long-term impact on aquatic environment. It was inferred that arbidol was photolyzed mainly via the loss of thiophenol, bromine, and alkylamine, based on twelve photolytic products identified. Notably, the experimental results demonstrated that the photolysis process increased the acute toxicity of arbidol, and the toxicity prediction indicated that the ecotoxicity of two photolytic products was very high with LC50 values below 0.1 mg/L. Due to the co-effect of multiple constituents, the photolytic rate observed in wastewater treatment plant effluent and in river water was comparable to that in ultra-pure water, while it was slightly enhanced in lake water. The presence of dissolved organic matter suppressed arbidol photolysis, while NO3- exhibited a promotion effect. These results would be of great significance to assess the fate and risk of COVID-19 antivirals in natural aquatic environments.


Assuntos
COVID-19 , Poluentes Químicos da Água , Humanos , Luz Solar , Fotólise , Água , Antivirais , Poluentes Químicos da Água/análise
4.
Sensors (Basel) ; 22(11)2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35684707

RESUMO

This paper investigates the computation offloading problem in mobile edge computing (MEC) networks with dynamic weighted tasks. We aim to minimize the system utility of the MEC network by jointly optimizing the offloading decision and bandwidth allocation problems. The optimization of joint offloading decisions and bandwidth allocation is formulated as a mixed-integer programming (MIP) problem. In general, the problem can be efficiently generated by deep learning-based algorithms for offloading decisions and then solved by using traditional optimization methods. However, these methods are weakly adaptive to new environments and require a large number of training samples to retrain the deep learning model once the environment changes. To overcome this weakness, in this paper, we propose a deep supervised learning-based computational offloading (DSLO) algorithm for dynamic computational tasks in MEC networks. We further introduce batch normalization to speed up the model convergence process and improve the robustness of the model. Numerical results show that DSLO only requires a few training samples and can quickly adapt to new MEC scenarios. Specifically, it can achieve 99% normalized system utility by using only four training samples per MEC scenario. Therefore, DSLO enables the fast deployment of computation offloading algorithms in future MEC networks.


Assuntos
Aprendizado Profundo , Algoritmos
5.
J Am Chem Soc ; 143(45): 19167-19177, 2021 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-34738793

RESUMO

Organosilicon compounds and polymers have found wide applications as synthetic building blocks and functional materials. Hydrosilylation is a common strategy toward the synthesis of organosilicon compounds and polymers. Although transition-metal-catalyzed hydrosilylation has achieved great advances, the metal-free hydrosilylation polymerization of dienes and bis(silane)s, especially the one suitable for both electron-rich and electron-deficient dienes, is largely lacking. Herein, we report a visible-light-driven metal-free hydrosilylation polymerization of both electron-rich and electron-deficient dienes with bis(silane)s by using the organic photocatalyst and hydrogen atom transfer (HAT) catalyst. We achieved the well-controlled step-growth hydrosilylation polymerizations of the electron-rich diene and bis(silane) monomer due to the selective activation of Si-H bonds by the organic photocatalyst (4CzIPN) and the thiol polarity reversal reagent (HAT 1). For the electron-deficient dienes, hydrosilylation polymerization and self-polymerization occurred simultaneously in the presence of 4CzIPN and aceclidine (HAT 2), providing the opportunity to produce linear, hyperbranched, and network polymers by rationally tuning the concentration of electron-deficient dienes and the ratio of bis(silane)s and dienes to alter the proportion of the two polymerizations. A wide scope of bis(silane)s and dienes furnished polycarbosilanes with high molecular weight, excellent thermal stability, and tunable architectures.

6.
Perfusion ; 36(5): 491-500, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32838661

RESUMO

BACKGROUND: The aim of this research was to use the Mehran risk score to classify elderly diabetics with coronary heart disease to assess the preventive effect of trimetazidine on contrast-induced nephropathy (CIN) after percutaneous coronary intervention (PCI) in different risk population. METHODS: An uncompromised of 760 elderly diabetics that went through PCI were included in this research. The patients were first divided into three groups in the light of MRS: low-risk, moderate-risk, and high-risk group, then randomized into trimetazidine group and the control group respectively. The first endpoint was the amount of CIN, which is described as a rise in serum creatinine levels by ⩾44.2 µmol/L or ⩾25% ratio within 48 or 72 hours after medication. Second endpoint included differences in creatinine clearance rate (CrCl), blood urea nitrogen (BUN), serum creatinine (Scr), cystatin-C (Cys-C), and the incidence of major adverse events after administration. RESULTS: In the three groups, the incidence of CIN in trimetazidine and control group was 5.0% versus 4.9%(χ2 = 0.005, p > 0.05), 8.0% versus 18.0% (χ2 = 7.685, p < 0.05), 10.4% versus 27.1% (χ2 = 4.376, p < 0.05), respectively. The multivariable logistic regression result demonstrated that trimetazidine intervention was a profitable element of CIN in moderate and high-risk groups (OR = 0.294, 95% CI 0.094-0.920, p = 0.035). CONCLUSION: Our study confirmed that trimetazidine can be considered for preventive treatment of CIN occurrence in elderly diabetics with moderate and high-risk population, while there is no obvious advantage compared with hydration therapy in low-risk patients.


Assuntos
Diabetes Mellitus , Nefropatias , Intervenção Coronária Percutânea , Trimetazidina , Idoso , Meios de Contraste/efeitos adversos , Angiografia Coronária , Creatinina , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Fatores de Risco , Trimetazidina/uso terapêutico
7.
Perfusion ; 36(6): 603-609, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32909511

RESUMO

BACKGROUND: Contrast-induced nephropathy (CIN) has become a common cause of hospital-acquired acute kidney injury in elderly patients. Trimetazidine (TMZ) is a type of anti-ischemic drug developed in recent years, which can reduce the incidence of CIN. This study aimed to evaluate the efficacy of TMZ in the prevention of contrast-induced nephropathy in elderly patients with renal insufficiency undergoing percutaneous coronary intervention (PCI) and to explore the mechanism of action. METHODS: A total of 310 elderly patients with renal insufficiency undergoing elective PCI were enrolled and randomly assigned to a control group (n = 155, hydration only) and a TMZ group (n = 155, 20 mg thrice daily orally 24 hours before and 72 hours after PCI). The primary endpoint of the study was the incidence of CIN, which was defined as an increase of 25% or more, or an absolute increase of 0.5 mg/dL or more in serum creatinine from baseline value, at 48 to 72 hours following the exposure to contrast media (CM). RESULTS: The incidence of CIN was significantly lower in the TMZ group than that in the control group (3.2% vs. 9.7%, p = 0.021). There was no difference regarding the incidence of major adverse events during hospitalization between the TMZ group and control group (1.9% vs. 2.6%, p = 1.000). Binary logistic regression results showed that TMZ was protective factors of CIN (OR = 0.274; 95% CI: 0.089-0.847; p = 0.025). CONCLUSION: Therefore, we came to the conclusion that prophylactic administration of TMZ can prevent the occurrence of CIN in elderly patients with renal insufficiency undergoing PCI and has a certain protective effect on the renal function of patients. According to the experimental results and the mechanism of TMZ on cardiomyocytes, we speculate that TMZ increases kidney glucose metabolism, reduces fatty acid oxidation, and also has a protective effect on kidney free radical damage and ischemia-reperfusion injury.


Assuntos
Injúria Renal Aguda , Nefropatias , Intervenção Coronária Percutânea , Insuficiência Renal , Trimetazidina , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/prevenção & controle , Idoso , Meios de Contraste/efeitos adversos , Angiografia Coronária , Creatinina , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Insuficiência Renal/complicações , Trimetazidina/uso terapêutico
8.
Langmuir ; 35(30): 9904-9911, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31282165

RESUMO

Aggregation behavior of an amphiphilic diblock copolymer poly(lauryl acrylate)-block-poly(N-isopropylacrylamide) (PLA-b-PNIPAM) on neutral aqueous subphases with different salt species and salt concentrations, as well as the structures of its Langmuir-Blodgett (LB) films, were systematically studied. The presence of NaCl or Na2SO4 in subphases makes PNIPAM chains shrink on the water surface and reduce their solubility underwater. On the contrary, the presence of NaNO3 or NaSCN makes PNIPAM chains more stretched on water and increase their solubility underwater, whose stretch degree and solubility both increase with the increase of salt concentration. Solubility of PNIPAM chains in the above subphase solutions is ranked as NaSCN ≫ NaNO3 > pure H2O > NaCl ≈ Na2SO4, which is almost consistent with the Hofmeister series except for the latter two close cases. All the initial LB films of PLA-b-PNIPAM exhibit tiny isolated circular micelles. Upon compression, the LB films in the case of pure H2O exhibit the dense mixed structures of circular micelles and wormlike aggregates. The formation of wormlike aggregates is due to connection of some adjoining cores, which is less possible in other subphase cases because of the conformation difference of PNIPAM chains.

9.
Catheter Cardiovasc Interv ; 91(4): 742-750, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29024304

RESUMO

BACKGROUND: The role of alprostadil on the prevention of contrast-induced nephropathy (CIN) still remains controversial. The purpose of this study was to examine the effects of short-term alprostadil on the incidence of CIN in patients undergoing elective percutaneous coronary intervention (PCI). METHODS: A total of 480 patients with coronary heart disease undergoing PCI were enrolled in our study and randomly assigned to two groups. The control group (n = 240) was given only hydration therapy and the alprostadil group (n = 240) received intravenous administration of 20 ug/day (diluted with 100 ml normal saline) from 0.5∼1 hr before to 3 days after operation on the basis of hydration. The primary endpoint of the study was the incidence of CIN, which was defined as an increase in SCr concentration ≥ 44.2 umol/l or ≥25% above baseline within 48 hr∼72 hr after exposure of contrast media. RESULTS: The incidence of CIN was significantly lower in the alprostadil group than that in the control group (6.25% vs 11.67%, P = 0.038). Multivariate logistic regression analysis showed that alprostadil was the protective factor of CIN (OR = 0.699, 95% CI 0.542-0.902, P = 0.006). The benefits against CIN were consistent in prespecified high-risk patients with diabetes mellitus (P = 0.003). In addition, we also found that hs-CRP and blood homocysteine values after PCI were significantly lower in the alprostadil group than those in the control group. CONCLUSION: Prophylactic administration of alprostadil may prevent against CIN in coronary heart disease patients undergoing elective PCI, particularly in high-risk patients with diabetes mellitus.


Assuntos
Alprostadil/administração & dosagem , Meios de Contraste/efeitos adversos , Angiografia Coronária/efeitos adversos , Doença das Coronárias/cirurgia , Nefropatias/prevenção & controle , Intervenção Coronária Percutânea/efeitos adversos , Vasodilatadores/administração & dosagem , Idoso , Alprostadil/efeitos adversos , Biomarcadores/sangue , China/epidemiologia , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/epidemiologia , Creatinina/sangue , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Incidência , Infusões Intravenosas , Nefropatias/induzido quimicamente , Nefropatias/diagnóstico , Nefropatias/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Proteção , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Regulação para Cima , Vasodilatadores/efeitos adversos
10.
Mol Ther ; 25(11): 2452-2465, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28807568

RESUMO

Anti-CD19 chimeric antigen receptor (CAR) T cells have caused remissions of B cell malignancies, but problems including cytokine-mediated toxicity and short persistence of CAR T cells in vivo might limit the effectiveness of anti-CD19 CAR T cells. Anti-CD19 CARs that have been tested clinically had single-chain variable fragments (scFvs) derived from murine antibodies. We have designed and constructed novel anti-CD19 CARs containing a scFv with fully human variable regions. T cells expressing these CARs specifically recognized CD19+ target cells and carried out functions including degranulation, cytokine release, and proliferation. We compared CARs with CD28 costimulatory moieties along with hinge and transmembrane domains from either the human CD28 molecule or the human CD8α molecule. Compared with T cells expressing CARs with CD28 hinge and transmembrane domains, T cells expressing CARs with CD8α hinge and transmembrane domains produced lower levels of cytokines and exhibited lower levels of activation-induced cell death (AICD). Importantly, CARs with hinge and transmembrane regions from either CD8α or CD28 had similar abilities to eliminate established tumors in mice. In anti-CD19 CARs with CD28 costimulatory moieties, lower levels of inflammatory cytokine production and AICD are potential clinical advantages of CD8α hinge and transmembrane domains over CD28 hinge and transmembrane domains.


Assuntos
Antígenos CD28/imunologia , Antígenos CD8/imunologia , Imunoterapia Adotiva/métodos , Leucemia Linfocítica Crônica de Células B/terapia , Receptores de Antígenos de Linfócitos T/imunologia , Anticorpos de Cadeia Única/genética , Linfócitos T/imunologia , Sequência de Aminoácidos , Animais , Antígenos CD19/genética , Antígenos CD19/imunologia , Antígenos CD28/genética , Antígenos CD8/genética , Linhagem Celular Tumoral , Expressão Gênica , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/imunologia , Leucemia Linfocítica Crônica de Células B/patologia , Transfusão de Linfócitos , Camundongos , Plasmídeos/química , Plasmídeos/metabolismo , Domínios Proteicos , Receptores de Antígenos de Linfócitos T/genética , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Anticorpos de Cadeia Única/química , Análise de Sobrevida , Linfócitos T/citologia , Linfócitos T/transplante , Transdução Genética , Carga Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Catheter Cardiovasc Interv ; 83(1): E8-16, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23907993

RESUMO

OBJECTIVE: To develop a simple scoring system based on preprocedural clinical features that is capable of predicting contrast-induced acute kidney injury (CI-AKI) before percutaneous coronary intervention (PCI). BACKGROUND: CI-AKI is associated with increased in-hospital morbidity and mortality, prolonged hospitalization, and long-term renal impairment. Although several scoring methods have been developed to determine risk of CI-AKI, no simple scoring method based on PCI preprocedural clinical features yet exists for Chinese patients. METHODS: A total of 2,500 Chinese patients were randomly and retrospectively assigned in a 3:2 manner to create a training and validation dataset, respectively. CI-AKI was defined as an increase of ≥25% or ≥0.5 mg/dL serum creatinine within 5 days after PCI. Preprocedural clinical variables showing independent correlation to CI-AKI were used to derive the risk score from the training dataset and then subsequently tested in the validation dataset. The odds ratios from multivariate logistic regression were used to assign a weighted integer to age ≥70 years = 4, history of myocardial infarction = 5, diabetes mellitus = 4, hypotension = 6, left ventricular ejection fraction ≤45% = 4, anemia = 3, creatinine clearance rate <60 mL/min = 7, decreased high-density lipoprotein <1 mmol/L= 3, and urgent PCI = 3. Summation of the integers represented the total risk score. RESULTS: The overall incidence of CI-AKI in the training dataset was 16.4% [246/1500; 5.4% for low (≤7) and 61.3% for very high (≥17) risk scores]. The rates of CI-AKI, 1-year dialysis, and 1-year mortality increased significantly with each group (Cochran-Armitage test of trend, P < 0.001). The risk score facilitated appropriate classification of patients with low and high risk for CI-AKI after PCI in the validation dataset (c-statistic = 0.82). CONCLUSION: Risk classification based on the most significantly correlated parameters is useful for predicting CI-AKI before contrast exposure. The simple preprocedural score showed excellent predictive ability for identifying patients at high risk of nephropathy and those with deteriorative prognosis after PCI.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Meios de Contraste/efeitos adversos , Intervenção Coronária Percutânea/efeitos adversos , Injúria Renal Aguda/sangue , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/mortalidade , Injúria Renal Aguda/terapia , Idoso , Biomarcadores/sangue , China/epidemiologia , Creatinina/sangue , Técnicas de Apoio para a Decisão , Mortalidade Hospitalar , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Intervenção Coronária Percutânea/mortalidade , Valor Preditivo dos Testes , Prognóstico , Diálise Renal , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo
12.
Front Psychol ; 15: 1408022, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38840739

RESUMO

Introduction: Adolescence is considered a stress-sensitive developmental period, and the escalating and sustained pressure during this phase poses a significant threat to the mental and physical well-being of adolescents. Therefore, enhancing positive emotions in adolescents is crucial. This study aims to investigate the impact of physical activity on the emotional intelligence, interpersonal forgiveness, and positive emotions of adolescents. Methods: Using a cluster sampling method, data were collected from 500 adolescents in four schools across the Xiangxi Tujia and Miao Autonomous Prefecture of Hunan Province, China. A total of 428 valid questionnaires were collected and analyzed. The study employed AMOS v.23 to construct a structural equation model to validate the hypotheses. Results: The results indicate that physical activity significantly influences the emotional intelligence, interpersonal forgiveness, and positive emotions of adolescents. Furthermore, emotional intelligence and interpersonal forgiveness mediate the relationship between physical activity and positive emotions. Discussion: Based on these findings, collaborative efforts from government agencies, schools, and families are essential to provide robust support for adolescents' participation in physical activity, encouraging more adolescents to actively engage in sports.

13.
Artigo em Inglês | MEDLINE | ID: mdl-39420230

RESUMO

In 2020, the top 10 causes of death among children and adolescents between the ages of 1 and 19 years old included cancer, congenital anomalies, heart disease, and chronic respiratory disease; all these conditions are potentially treatable with medical intervention. However, children exhibit specific physiological and developmental characteristics that can significantly impact drug pharmacokinetics, pharmacodynamics, and safety profile. These factors illustrate the importance of a heightened focus on pediatric drug development. Traditional drugs lack proper circulation, permeability, targeting, accumulation, and release, and they often require dose adjustments or modifications, which can result in suboptimal therapeutic outcomes and increased risks of adverse effects in pediatric patients. Nanomedicines have emerged as efficient drug delivery systems because of their unique properties, which can improve the solubility and stability of drugs by encapsulating them in different forms of nanoparticles. This review discusses the challenges of pediatric therapy, and the current state of nanomedicines for pediatric diseases in terms of Food and Drug Administration-approved nanomedicines, the types of diseases treated or diagnosed, and preclinical studies that have the potential to be translated to the clinic. In summary, nanomedicine holds significant potential for addressing the unique and pressing challenges associated with diagnosing and treating pediatric diseases.


Assuntos
Nanomedicina , Humanos , Criança , Sistemas de Liberação de Medicamentos , Animais , Adolescente , Pré-Escolar , Lactente , Pediatria , Neoplasias/tratamento farmacológico , Nanopartículas/química , Nanopartículas/uso terapêutico
14.
ACS Macro Lett ; 13(6): 711-718, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38767947

RESUMO

Based on the characteristics of commodity polymers in large quantities and low costs, modification of existing commodity polymers emerges as the most effective approach for exploring novel materials. Nevertheless, conventional modification methods typically involve high-energy processes (e.g., high temperature, high-energy radiation), which may lead to irreversible detrimental effects on the polymers, contradicting the desired performance enhancement through modification. In this work, we propose a carbene-mediated postpolymerization modification (PPM) strategy utilizing diazo compounds. Under photochemical or thermal activation conditions, insertion of the C-H bond can be achieved without compromising the performance of polymers. These diazo compounds can be easily synthesized in just two steps and applied to all C-H-containing polymers. This practical and effective modification strategy offers new opportunities and possibilities for enhancing the value and expanding the applications of polymers.

15.
Int J Pharm ; 650: 123700, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38086493

RESUMO

Due to their low osmolality and high tolerability, the highly water-soluble nonionic iodinated contrast agents, such as Ioversol (IV), are widely used as clinical agents for CT imaging. However, their clinical applications still are severely limited by the rapid renal excretion, serious adverse effects especially contrast-induced nephropathy and inefficient targetability. Various nanocarriers have demonstrated tremendous potential for achieving high imaging efficiency and low side effects. However, few nanoparticulate contrast agents can simultaneously integrate the desirable functions for imaging, including high loading capacity of iodine, high structure stability for systemic circulation, high biocompatibility and high radiopacity. Herein, we designed and prepared a kind of new radiopaque liposome-camouflaged iodinated mesoporous silica nanoparticles (OIV-MSNs@Liposomes) as contrast agents in CT imaging. Their composition, structure, morphology, biocompatibility and physicochemical properties as well as in vitro radiopacity were investigated in detail. The results indicated that OIV-MSNs@Liposomes can integrate their individual advantages of liposomes and MSNs, thus exhibiting great potential for use in the CT imaging. Considering the simple preparation process and readily available starting materials as well as enhanced biosafety and high performance in X-ray attenuation, the strategy reported here offers a versatile route to efficiently deliver highly water-soluble nonionic iodinated contrast agents for enhanced CT imaging, which are unattainable by traditional means.


Assuntos
Meios de Contraste , Nanopartículas , Meios de Contraste/química , Dióxido de Silício/química , Lipossomos , Nanopartículas/química , Água , Hemodinâmica , Porosidade
16.
Macromol Biosci ; : e2400383, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39401274

RESUMO

The therapeutic efficacy of bortezomib (BTZ) is often limited due to low solubility, poor stability in vivo and nonspecific toxicity. Herein, a kind of catechol-functionalized polyethylene glycol (mPEG-CA) is first synthesized and then mPEG-CA is readily used to conjugate with BTZ by the formation of dynamic boronate bonds to obtain PEGlyated BTZ prodrug (mPEG-CA-BTZ) with the ability of pH-controlled disassembly and drug release. The structure and morphology, physicochemical characteristics, drug loading, and release as well as in vitro cytotoxicity of mPEG-CA-BTZ nanoparticles are investigated in detail. The results demonstrated that mPEG-CA-BTZ can not only self-assemble into nanostructures with uniform size and stable dispersion in physiological pH condition (pH 7.4) but also respond to the tumor acid microenvironment and achieve pH-controlled BTZ release by acid-triggered cleavage of boronate bonds, decomposition of mPEG-CA-BTZ and thus disassembly of mPEG-CA-BTZ nanoparticles. mPEG-CA-BTZ nanoparticles are expected to have great potential as a promising nanoplatform for pharmaceutical formulations of BTZ to increase therapeutic efficacy and decrease side effects of BTZ. Considering the easily available and biocompatible excipients and simple preparation process, the strategy designed herein provides a facile and promising approach to synergistically integrate the function of PEGylation and pH-sensitiveness into boronic acid-containing small molecule pharmaceutical agents.

17.
Cancer Immunol Immunother ; 62(11): 1649-62, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23982483

RESUMO

Adoptive cell transfer (ACT) using ex vivo-expanded anti-tumor T cells such as tumor-infiltrated lymphocytes or genetically engineered T cells potently eradicates established tumors. However, these two approaches possess obvious limitations. Therefore, we established a novel methodology using total tumor RNA (ttRNA) to prime dendritic cells (DC) as a platform for the ex vivo generation of anti-tumor T cells. We evaluated the antigen-specific expansion and recognition of T cells generated by the ttRNA-DC-T platform, and directly modulated the differentiation status of these ex vivo-expanded T cells with a cytokine cocktail. Furthermore, we evaluated the persistence and in vivo anti-tumor efficacy of these T cells through murine xenograft and syngeneic tumor models. During ex vivo culture, IL-2 preferentially expanded CD4 subset, while IL-7 enabled homeostatic proliferation from the original precursors. T cells tended to lose CD62L during ex vivo culture using IL-2; however, IL-12 could maintain high levels of CD62L by increasing expression on effector T cells (Tem). In addition, we validated that OVA RNA-DC only selectively expanded T cells in an antigen-specific manner. A cytokine cocktail excluding the use of IL-2 greatly increased CD62Lhigh T cells which specifically recognized tumor cells, engrafted better in a xenograft model and exhibited superior anti-tumor activities in a syngeneic intracranial model. ACT using the ex vivo ttRNA-DC-T platform in conjunction with a cytokine cocktail generated potent CD62Lhigh anti-tumor T cells and imposes a novel T cell-based therapeutic with the potential to treat brain tumors and other cancers.


Assuntos
Citocinas/imunologia , Células Dendríticas/imunologia , Neoplasias/imunologia , Linfócitos T/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Citocinas/farmacologia , Citotoxicidade Imunológica/efeitos dos fármacos , Citotoxicidade Imunológica/imunologia , Células Dendríticas/metabolismo , Células Dendríticas/transplante , Feminino , Citometria de Fluxo , Humanos , Imunofenotipagem , Imunoterapia Adotiva/métodos , Subunidade gama Comum de Receptores de Interleucina/deficiência , Subunidade gama Comum de Receptores de Interleucina/genética , Selectina L/imunologia , Selectina L/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Neoplasias/patologia , Neoplasias/terapia , RNA Neoplásico/imunologia , Linfócitos T/metabolismo , Linfócitos T/transplante
18.
Cancer Immunol Immunother ; 62(4): 727-36, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23207483

RESUMO

The genetic modification of CD8+ T cells using anti-tumor T-cell receptors (TCR) or chimeric antigen receptors is a promising approach for the adoptive cell therapy of patients with cancer. We previously developed a simplified method for the clinical-scale generation of central memory-like (Tcm) CD8+ T cells following transduction with lentivirus encoding anti-tumor TCR and culture in the presence of IL-2. In this study, we compared different cytokines or combinations of IL-2, IL-7, IL-12, IL-15, and IL-21 to expand genetically engineered CD8+ T cells. We demonstrated that specific cytokine combinations IL-12 plus IL-7 or IL-21 for 3 days followed by withdrawal of IL-12 yielded the phenotype of CD62L(high)CD28(high) CD127(high)CD27(high)CCR7(high), which is associated with less-differentiated T cells. Genes associated with stem cells (SOX2, NANOG, OCT4, and LIN28A), were also up-regulated by this cytokine cocktail. Moreover, the use of IL-12 plus IL-7 or IL-21 yielded CD8 T cells showing enhanced persistence in the NOD/SCID/γc-/- mouse model. This defined cytokine combination could also alter highly differentiated TIL from melanoma patients into cells with a less-differentiated phenotype. The methodology that we developed for generating a less-differentiated anti-tumor CD8+ T cells ex vivo may be ideal for the adoptive immunotherapy of cancer.


Assuntos
Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Citocinas/imunologia , Citocinas/farmacologia , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos do Interstício Tumoral/imunologia , Animais , Linfócitos T CD8-Positivos/citologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Humanos , Interleucinas/imunologia , Interleucinas/farmacologia , Linfócitos do Interstício Tumoral/citologia , Melanoma/imunologia , Melanoma/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Fenótipo
19.
Blood ; 117(3): 808-14, 2011 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-20971955

RESUMO

Cluster of differentiation (CD)8(+) T cells exist as naive, central memory, and effector memory subsets, and any of these populations can be genetically engineered into tumor-reactive effector cells for adoptive immunotherapy. However, the optimal subset from which to derive effector CD8(+) T cells for patient treatments is controversial and understudied. We investigated human CD8(+) T cells and found that naive cells were not only the most abundant subset but also the population most capable of in vitro expansion and T-cell receptor transgene expression. Despite increased expansion, naive-derived cells displayed minimal effector differentiation, a quality associated with greater efficacy after cell infusion. Similarly, the markers of terminal differentiation, killer cell lectin-like receptor G1 and CD57, were expressed at lower levels in cells of naive origin. Finally, naive-derived effector cells expressed higher CD27 and retained longer telomeres, characteristics that suggest greater proliferative potential and that have been linked to greater efficacy in clinical trials. Thus, these data suggest that naive cells resist terminal differentiation, or "exhaustion," maintain high replicative potential, and therefore may be the superior subset for use in adoptive immunotherapy.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Memória Imunológica/imunologia , Imunoterapia Adotiva/métodos , Subpopulações de Linfócitos T/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/transplante , Diferenciação Celular/imunologia , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Citocinas/metabolismo , Citometria de Fluxo , Expressão Gênica , Vetores Genéticos/genética , Humanos , Retroviridae/genética , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/transplante , Telômero/genética , Transdução Genética , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo
20.
J Hazard Mater ; 452: 131320, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37002997

RESUMO

Increasing drug residues in aquatic environments have been caused by the abuse of antivirals since the global spread of the COVID-19 epidemic, whereas research on the photolytic mechanism, pathways and toxicity of these drugs is limited. The concentration of COVID-19 antivirals ribavirin in rivers has been reported to increase after the epidemic. Its photolytic behavior and environmental risk in actual waters such as wastewater treatment plant (WWTP) effluent, river water and lake water were first investigated in this study. Direct photolysis of ribavirin in these media was limited, but indirect photolysis was promoted in WWTP effluent and lake water by dissolved organic matter and NO3-. Identification of photolytic intermediates suggested that ribavirin was photolyzed mainly via C-N bond cleavage, splitting of the furan ring and oxidation of the hydroxyl group. Notably, the acute toxicity was increased after ribavirin photolysis owing to the higher toxicity of most of the products. Additionally, the overall toxicity was greater when ARB photolysis in WWTP effluent and lake water. These findings emphasize the necessity to concern about the toxicity of ribavirin transformation in natural waters, as well as to limit its usage and discharge.


Assuntos
Antivirais , COVID-19 , Ribavirina , Poluentes Químicos da Água , Humanos , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Antivirais/química , Fotólise , Ribavirina/química , Água/química , Poluentes Químicos da Água/química
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