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1.
Proc Natl Acad Sci U S A ; 121(13): e2315407121, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38502699

RESUMO

Organic electrodes mainly consisting of C, O, H, and N are promising candidates for advanced batteries. However, the sluggish ionic and electronic conductivity limit the full play of their high theoretical capacities. Here, we integrate the idea of metal-support interaction in single-atom catalysts with π-d hybridization into the design of organic electrode materials for the applications of lithium (LIBs) and potassium-ion batteries (PIBs). Several types of transition metal single atoms (e.g., Co, Ni, Fe) with π-d hybridization are incorporated into the semiconducting covalent organic framework (COF) composite. Single atoms favorably modify the energy band structure and improve the electronic conductivity of COF. More importantly, the electronic interaction between single atoms and COF adjusts the binding affinity and modifies ion traffic between Li/K ions and the active organic units of COFs as evidenced by extensive in situ and ex situ characterizations and theoretical calculations. The corresponding LIB achieves a high reversible capacity of 1,023.0 mA h g-1 after 100 cycles at 100 mA g-1 and 501.1 mA h g-1 after 500 cycles at 1,000 mA g-1. The corresponding PIB delivers a high reversible capacity of 449.0 mA h g-1 at 100 mA g-1 after 150 cycles and stably cycled over 500 cycles at 1,000 mA g-1. This work provides a promising route to engineering organic electrodes.

2.
J Am Chem Soc ; 146(26): 17931-17939, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38877992

RESUMO

Complex micro/nanorobots may be constructed by integrating several independent, controlled nanomotors for high degrees of freedom of maneuvering and manipulation. However, designing nanomotors with distinctive responses to the same global stimuli is challenging due to the nanomotors' simple structure and limited material composition. In this work, we demonstrate that a nanomotor can be designed with the same principles of electronic circuits, where the motion of semiconductor particles can be controlled with synchronized electric and optical signals. This technique relies on transient bipolar photoelectrochemistry in semiconductor microparticles, where the reaction site selectivity is realized by modulating the light pulse in the time domain. Due to the microparticles' intrinsic resistance and surface capacitance, the nanomotors can be designed as an electronic circuit, enabling distinctive responses to the global electric/optical field and achieving the desired movement or deflection/rotation. This work gives new insight into the manipulation technique for independent and untethered nanomotor control. Ultimately, it exploits the potential for particle sorting based on geometry in time and frequency domain modulation.

3.
Acta Pharmacol Sin ; 45(7): 1337-1348, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38351317

RESUMO

Transforming growth factor-ß (TGF-ß) signaling is initiated by activation of transmembrane TGF-ß receptors (TGFBR), which deploys Smad2/3 transcription factors to control cellular responses. Failure or dysregulation in the TGF-ß signaling pathways leads to pathological conditions. TGF-ß signaling is regulated at different levels along the pathways and begins with the liberation of TGF-ß ligand from its latent form. The mechanisms of TGFBR activation display selectivity to cell types, agonists, and TGF-ß isoforms, enabling precise control of TGF-ß signals. In addition, the cell surface compartments used to release active TGF-ß are surprisingly vibrant, using thrombospondins, integrins, matrix metalloproteinases and reactive oxygen species. The scope of TGFBR activation is further unfolded with the discovery of TGFBR activation initiated by other signaling pathways. The unique combination of mechanisms works in series to trigger TGFBR activation, which can be explored as therapeutic targets. This comprehensive review provides valuable insights into the diverse mechanisms underpinning TGFBR activation, shedding light on potential avenues for therapeutic exploration.


Assuntos
Receptores de Fatores de Crescimento Transformadores beta , Transdução de Sinais , Fator de Crescimento Transformador beta , Humanos , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Ligantes , Animais , Fator de Crescimento Transformador beta/metabolismo
4.
Angew Chem Int Ed Engl ; 63(1): e202316208, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37990065

RESUMO

Green organic materials composed of C, H, O, and N elements are receiving more and more attention worldwide. However, the high solubility, poor electrical conductivity, and long activation time limit the development of organic materials in practice. Herein, two stable covalent organic materials with alkynyl linkage between benzene rings and benzothiadiazole groups with different amounts of fluorine atoms modification (defined as BOP-0F and BOP-2F), are designed for lithium-ion batteries. Both BOP-0F and BOP-2F can achieve superior reversible capacities of ≈719.8 and 713.5 mAh g-1 over 100 cycles on account of the redox activity of alkynyl (two-electron involved) and benzothiadiazole units (five-electron involved) in these organic materials. While BOP-2F electrodes exhibit much more stable cycling performance than BOP-0F electrodes, especially without pronounced capacity ascending during initial cycling. It can be assigned to the synergy effect of alkynyl linkage and fluorine atom modification in BOP-2F. The lithium storage and activation mechanism of alkynyl, benzothiadiazole, and fluorine groups have also been deeply probed by a series of material characterizations and theoretical simulations. This work could be noteworthy in providing novel tactics for the molecular design and investigation of high-efficiency organic electrodes for energy storage.

5.
Angew Chem Int Ed Engl ; 63(15): e202320259, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38332561

RESUMO

Fatal issues in lithium metal anodes (LMA), such as detrimental lithium dendrites growth and fragile solid-electrolyte interphase (SEI) during the Li plating/stripping process, often hinder the practical application of Li metal batteries (LMBs). Herein, cobalt-coordinated sp-carbon-conjugated organic polymer (Co-spc-COP) is constructed as the protective layer for regulating the interface stability of LMA. The unique synergistic beneficial effect of organic functional groups (C≡C linkage, C=N units and aromatic rings) and Co sites not only regulate the Li+ coordination environment and rearrange Li+ concentration to facilitate its transport by optimizing the electronic density, enhancing the compatibility with electrolyte interface and supplying "external magnetic driving strategy", but also strengthens the interfacial stiffness with high Young's modulus to better withstand the mechanical stress. These beneficial effects and relative underlying working mode and mechanism of uniform Li plating and rapid Li+ migration on the Co-spc-COP are also revealed by various in situ/ex situ experimental technologies and theory calculation. The Co-spc-COP-based cell delivers an extraordinary lifespan of 6600 h and ultrahigh capacity retention of 78.3 % (111.9 mAh g-1) after 1000 cycles at 1 C. This demonstrated synergistic strategy in Co-coordinated organic polymer may gain new insights to regulate the uniform and non-dendritic deposition/dissolution behaviors for highly stable LMBs.

6.
J Am Chem Soc ; 145(36): 19945-19952, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37641545

RESUMO

Thermophoretic micro/nanomotors (MNMs) generate self-propulsion without a chemical reaction. Intrinsically, this promises excellent biocompatibility and is thus suitable for biomedical applications. However, their propulsion efficiency is severely limited due to the poor understanding of the thermophoretic process, which dominates the conversion from thermal energy into mechanical movement. We here developed a series of self-thermophoresis light-powered MNMs with variable surface coatings and discovered obvious self-thermophoresis propulsion enhancement of the polymeric layer. An intrinsically negative self-thermophoretic movement is also observed for the first time in the MNM system. We propose that enthalpic contributions from polymer-solvent interactions should play a fundamental role in the self-thermophoretic MNMs. Quantitative microcalorimetry and molecular dynamics simulations are performed to support our hypothesis. The polymer solvation enthalpy and coating thickness influences on self-thermophoresis are investigated, further highlighting the essential enthalpy contributions to thermophoresis. Our work indicates that surface grafting would be important in designing high-efficiency thermally driven nanorobotic systems for biomedical applications.

7.
Waste Manag Res ; : 734242X231190811, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37555586

RESUMO

Soil microplastic pollution is currently a worldwide concern. Microplastics are organic pollutants that are abundant in the natural environment, are persistent and difficult to degrade and may endanger human health while harming the environment. This article offers a bibliometric analysis of the environmental behaviour of microplastics in soils, as well as a thorough statistical analysis of research goals and trends in this field. We conducted a thorough search of all relevant literature from 2012 to 2022 in the Web of Science core database. The data analysis shows that, starting in 2012, there has been an upward trend in the number of articles about soil microplastic pollution. It can also be seen that China is relatively ahead of the curve in this area of research, followed by the United Kingdom and the United States. This article also systematically describes the research hotspots in this field. The results show that the current research on soil microplastics is mainly focused on their identification, enrichment and toxicity, whereas studies on the migration and transformation of soil microplastics and the mechanism of interaction with other pollutants are still lacking. Our results provide ideas and prospects for future research in this field.

8.
Angew Chem Int Ed Engl ; 62(30): e202302143, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37269463

RESUMO

The poor conductivity of the pristine bulk covalent organic material is the main challenge for its application in energy storage. The mechanism of symmetric alkynyl bonds (C≡C) in covalent organic materials for lithium storage is still rarely reported. Herein, a nanosized (≈80 nm) alkynyl-linked covalent phenanthroline framework (Alkynyl-CPF) is synthesized for the first time to improve the intrinsic charge conductivity and the insolubility of the covalent organic material in lithium-ion batteries. Because of the high degree of electron conjugation along alkynyl units and N atoms from phenanthroline groups, the Alkynyl-CPF electrodes with the lowest HOMO-LUMO energy gap (ΔE=2.629 eV) show improved intrinsic conductivity by density functional theory (DFT) calculations. As a result, the pristine Alkynyl-CPF electrode delivers superior cycling performance with a large reversible capacity and outstanding rate properties (1068.0 mAh g-1 after 300 cycles at 100 mA g-1 and 410.5 mAh g-1 after 700 cycles at 1000 mA g-1 ). Moreover, by Raman, FT-IR, XPS, EIS, and theoretical simulations, the energy-storage mechanism of C≡C units and phenanthroline groups in the Alkynyl-CPF electrode has been investigated. This work provides new strategies and insights for the design and mechanism investigation of covalent organic materials in electrochemical energy storage.

9.
Angew Chem Int Ed Engl ; 61(48): e202213276, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36196009

RESUMO

The rechargeable lithium/sodium-iodine battery (Li/Na-I2 ) is a promising candidate for meeting the growing energy demand. Herein, a flexible hydrogen-bonded organic framework (HOF) linked to the Ti3 C2 Tx MXene complex (HOF@Ti3 C2 Tx ) has been presented for iodine loading. HOF is self-assembled by organic monomers through hydrogen bonding interactions between each monomer. It leads to numerous cavities in HOF structure, which can encapsulate iodine through various adsorptive sites and intermolecular interactions. The unique structure of complex can accelerate the nucleation of iodine, achieve fast reaction kinetics, stabilize iodide and retard the shuttle effect, thus improving the cycling stability of I2 -based batteries. The I2 /HOF@Ti3 C2 Tx exhibits large reversible capacities of 260.2 and 207.6 mAh g-1 at 0.2 C after repeated cycling for Li-I2 and Na-I2 batteries, respectively. This work can gain insights into the HOF-related energy storage application with reversible iodine encapsulation and its related redox reaction mechanisms with Li and Na metal ions.

10.
Langmuir ; 37(19): 5916-5922, 2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-33909431

RESUMO

High-performance formaldehyde sensors play an important role in air quality assessment. Herein, a self-assembled monolayer (SAM) sensor for trace formaldehyde (FA) is fabricated based on the fluorescence enhancement of oxidized thiophene derivatives. In the primary SAM molecules, the functional backbone trithiophene (3T) links to the anchor through an n-propyl group. The anchor with an active Si-Cl bond can form a covalent bond with the SiO2 substrate by solution incubation, which ensures good stability against organic solvents and high sensitivity via monolayer structures. With the alkyl chain's leading, a dense 3T SAM can be obtained on SiO2. Upon exposure to UV light in the presence of oxygen, 3T can be oxidized into a nonfluorescent but coordination-active product with abundant carbonyl groups, which can be doped with FA and induce a blueshifted fluorescence. With this mechanism, we proposed an SAM-based FA sensor by detecting the enhancement of the blueshifted fluorescence. Reliable reversibility, selectivity, stability, and detection limit lower than 1 ppm are achieved in this system. The work provides an experimental basis for developing a cheap, efficient, and flexible sensor for trace FA detection.

11.
Macromol Rapid Commun ; 42(23): e2100551, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34610177

RESUMO

This work has prepared polymeric self-assembled monolayer (SAM) sensors for the detection of trace volatile nitroaromatic compound (NAC) explosives by fluorescence quenching. A typical aggregation-induced emission (AIE) luminogen 1,1,2,2-tetraphenylethene (TPE) polymerizes into PTPE to increase the fluorescence intensity in the SAMs, and the phosphoric acid acts as the anchor group to form stable covalent bonds with the Al2 O3 substrate. This design takes advantage of the high sensitivity and good stability of SAMs, and high fluorescence intensity, and "wire effect" of the conjugated polymers. The polymeric SAM sensors are prepared on the Al2 O3 silicon wafer and testing paper. Both of them show good response speed, reversibility, selectivity, and sensitivity. The detection limits down to 0.07, 0.35, and 4.11 ppm for TNT, DNB, and NB, respectively, are achieved on the inorganic testing paper. Furthermore, due to the higher fluorescence intensity by interlacing and overlapping of fibers, the detection of the paper can be distinguished by naked eyes even with a low-power handheld UV lamp, which provides an experimental basis for the development of cheap and easy trace NAC explosive sensors.


Assuntos
Substâncias Explosivas , Fluorescência , Polímeros
12.
J Nanobiotechnology ; 18(1): 144, 2020 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-33069258

RESUMO

BACKGROUND: During the course of gene transfection, the interaction kinetics between liposomes and DNA is speculated to play very important role for blood stability, cellular uptake, DNA release and finally transfection efficiency. RESULTS: As cationic peptide liposomes exhibited great gene transfer activities both in vitro and in vivo, two peptide lipids, containing a tri-ornithine head (LOrn3) and a mono-ornithine head (LOrn1), were chosen to further clarify the process of liposome-mediated gene delivery in this study. The results show that the electrostatically-driven binding between DNA and liposomes reached nearly 100% at equilibrium, and high affinity of LOrn3 to DNA led to fast binding rate between them. The binding process between LOrn3 and DNA conformed to the kinetics equation: y = 1.663631 × exp (- 0.003427x) + 6.278163. Compared to liposome LOrn1, the liposome LOrn3/DNA lipoplex exhibited a faster and more uniform uptake in HeLa cells, as LOrn3 with a tri-ornithine peptide headgroup had a stronger interaction with the negatively charged cell membrane than LOrn1. The efficient endosomal escape of DNA from LOrn3 lipoplex was facilitated by the acidity in late endosomes, resulting in broken carbamate bonds, as well as the "proton sponge effect" of the lipid. CONCLUSIONS: The interaction kinetics is a key factor for DNA transfection efficiency. This work provided insights into peptide lipid-mediated DNA delivery that could guide the development of the next generation of delivery systems for gene therapeutics.


Assuntos
Terapia Genética/métodos , Lipídeos/química , Lipossomos/química , Peptídeos/química , Cátions/química , Membrana Celular , DNA/química , Endossomos , Técnicas de Transferência de Genes , Células HeLa , Humanos , Cinética , Lipossomos/metabolismo , Transfecção
13.
Environ Sci Technol ; 53(7): 3697-3706, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30816704

RESUMO

Photocatalytic fuel cells (PFCs) have proven to be effective for generating electricity and degrading pollutants with a goal to resolve environmental and energy problems. However, the degradation of persistent organic pollutants (POPs), such as perfluorooctanoic acid (PFOA), remains challenging. In the present work, a porous coral-like WO3/W (PCW) photoelectrode with a well-designed energy band structure was used for the photoelectrocatalytic degradation of POPs and the simultaneous generation of electricity. The as-constructed bionic porous coral-like nanostructure greatly improved the light-harvesting capacity of the PCW photoelectrode. A maximum photocurrent density (0.31 mA/cm2) under visible light (λ > 420 nm) irradiation and a high incident photon conversion efficiency (IPCE) value (5.72% at 420 nm) were achieved. Because of the unique porous coral-like structure, the suitable energy band position, and the strong oxidation ability, this PCW photoelectrode-based PFC system exhibited a strong ability for simultaneous photoelectrocatalytic degradation of PFOA and electricity generation under visible-light irradiation, with a power output of 0.0013 mV/cm2 using PFOA as the fuel. This work provides a promising way to construct a reliable PFC using highly toxic POPs to generate electricity.


Assuntos
Antozoários , Animais , Eletricidade , Eletrodos , Luz , Porosidade
14.
J Pharmacol Exp Ther ; 365(1): 156-164, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29438988

RESUMO

Transforming growth factor-ß (TGF-ß) is a pleiotropic growth factor implicated in the development of atherosclerosis for its role in mediating glycosaminoglycan (GAG) chain hyperelongation on the proteoglycan biglycan, a phenomenon that increases the binding of atherogenic lipoproteins in the vessel wall. Phosphorylation of the transcription factor Smad has emerged as a critical step in the signaling pathways that control the synthesis of biglycan, both the core protein and the GAG chains. We have used flavopiridol, a well-known cyclin-dependent kinase inhibitor, to study the role of linker region phosphorylation in the TGF-ß-stimulated synthesis of biglycan. We used radiosulfate incorporation and SDS-PAGE to assess proteoglycan synthesis, real-time polymerase chain reaction to assess gene expression, and chromatin immunoprecipitation to assess the binding of Smads to the promoter region of GAG Synthesizing genes. Flavopiridol blocked TGF-ß-stimulated synthesis of mRNA for the GAG synthesizing enzymes, and chondroitin 4-sulfotransferase (C4ST-1), chondroitin sulfate synthase-1 (ChSy-1) and TGF-ß-mediated proteoglycans synthesis as well as GAG hyperelongation. Flavopiridol blocked TGF-ß-stimulated Smad2 phosphorylation at both the serine triplet and the isolated threonine residue in the linker region. The binding of Smad to the promoter region of the C4ST-1 and ChSy-1 genes was stimulated by TGF-ß, and this response was blocked by flavopiridol, demonstrating that linker region phosphorylated Smad can pass to the nucleus and positively regulate transcription. These results demonstrate the validity of the kinases, which phosphorylate the Smad linker region as potential therapeutic target(s) for the development of an agent to prevent atherosclerosis.


Assuntos
Biglicano/biossíntese , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Flavonoides/farmacologia , Piperidinas/farmacologia , Proteína Smad2/química , Proteína Smad2/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glicosaminoglicanos/metabolismo , Humanos , Músculo Liso Vascular/citologia , Fosforilação/efeitos dos fármacos , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Transdução de Sinais/efeitos dos fármacos
15.
Med Sci Monit ; 24: 3978-3986, 2018 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-29891832

RESUMO

BACKGROUND Doctors' empathy is closely related to patients' health. This study aimed to examine whether patients' stigma and self-efficacy play a mediating role in the relationship between doctors' empathy abilities and patients' cellular immunity in male patients with breast cancer. MATERIAL AND METHODS Doctors' empathy scores and patients' demographic data, disease condition, stigma, and self-efficacy were measured. Patient T cell subset was tested at admission and 3 months after the operation and was compared by paired t test. The multivariate linear regression model was applied to analyze the factors influencing the immune index. Pearson correlation analysis and structural equation modeling were applied to explore the relationships among patients' stigma, self-efficacy, and cellular immunity and doctors' empathy abilities. RESULTS At the 2 time points, only the change in NK subset was statistically significant, while the changes in percentage of CD3+, CD4+, CD8+, and B cells were not statistically significant. The doctors' empathy abilities were negatively correlated with patients' stigma and were positively related to patients' self-efficacy. Patients' stigma was negatively related to NK subset, while self-efficacy was positively associated with NK subset. Patients' stigma and self-efficacy played a mediating role in the relationship between doctors' empathy abilities and patients' NK subset, and stigma had a stronger effect than self-efficacy. CONCLUSIONS Doctors' empathy abilities affected breast cancer patients' NK subset through their stigma and self-efficacy. The mental health of male breast cancer patients need more attention and empathy education needs to be improved.


Assuntos
Neoplasias da Mama Masculina/psicologia , Relações Médico-Paciente , Adulto , Idoso , Atitude do Pessoal de Saúde , Atitude Frente a Saúde , China , Comunicação , Empatia , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Médicos , Autoeficácia , Estigma Social , Inquéritos e Questionários
16.
Allergy Asthma Proc ; 39(5): 332-337, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30153886

RESUMO

BACKGROUND: Several studies have evaluated the efficacy and safety of lebrikizumab treatment with uncontrolled asthma. However, most of these studies were small and conclusions were inconsistent. Furthermore, whether serum periostin can act as a good predictor of the response to lebrikizumab treatment is still not certain. METHOD: We conducted a systematic review and meta-analysis of randomized controlled trials to evaluate the efficacy and safety of lebrikizumab treatment with uncontrolled asthma. Trials were searched in PubMed, Embase, Web of Science and Cochrane. Outcome measures were the rate of asthma exacerbations, relative changes in the forced expiratory volume in the first second of expiration (FEV1) of predicted value (%) and incidence of adverse events. RESULT: Five trials were finally included. Compared with placebo lebrikizumab treatment significantly decreased the rate of exacerbations(risk ratio [RR] 0.66 [95% confidence interval {CI}, 0.54-0.80]; p < 0.0001; n = 2039) and increased FEV1% of predicted value (weighted mean difference [WMD] 5.46 [95% CI, 2.48-8.43]; p < 0.0003; n = 351). Patients with high levels of serum periostin had greater exacerbation rate reductions (RR 0.59 [95%CI, 0.50-0.70]; p < 0.00001; n = 1157) and FEV1 of predicted value improvement (WMD 7.18 [95% CI, 2.93-11.42]; p < 0.0009; n = 177) than patients with low periostin levels in exacerbation rate reductions (RR 0.73 [95% CI, 0.47-1.14]; p < 0.17; n = 882) and FEV1 of predicted value improvement (WMD3.79 [95% CI, 0.39-7.97]; p < 0.08; n = 174). There was no significant difference in the incidence of adverse events in patients with lebrikizumab compared to placebo (RR 1.03 [95% CI, 0.99-1.06]; p < 0.11; n = 2056). CONCLUSION: In patients with uncontrolled asthma, lebrikizumab treatment significantly decreased the rate of exacerbation and improved lung function, especially for patients with high periostin levels.


Assuntos
Antiasmáticos/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Asma/tratamento farmacológico , Interleucina-13/antagonistas & inibidores , Antiasmáticos/administração & dosagem , Antiasmáticos/efeitos adversos , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Asma/diagnóstico , Asma/metabolismo , Progressão da Doença , Resistência a Medicamentos , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Testes de Função Respiratória , Resultado do Tratamento
17.
Pak J Pharm Sci ; 31(3(Special)): 1145-1150, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29735465

RESUMO

In recent years, antitumor and antiviral effect of Caulis spatholobi becomes a hot topic of medical drug research. Experiment shows that the water extract of Caulis spatholobi compound 1802 showed the effect of inhibiting tumor growth, the difference was statistically significant (P<0.05); the rate of tumor inhibition was highest in the high dose group of compound 1802, which could reach 41.99%. Anti tumor drugs generally have high toxicity, therefore, low toxicity is the significant characteristic of Caulis spatholobi. In particular the use of Caulis spatholobi has certain practical significance for development of tumor patients' daily diet products. In summary, the chemical constituents of Caulis spatholobi complex, has extensive pharmacological effects and clinical application.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Neoplasias Experimentais/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Fabaceae/química , Humanos , Masculino , Camundongos , Extratos Vegetais/farmacologia
18.
Analyst ; 141(10): 3033-40, 2016 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-27069984

RESUMO

We present a 200 nm in-diameter single-bead sensor for the detection of single, unlabeled DNA molecules in solution using fluorescence resonance energy transfer technology. DNA-bound Alexa 488 and Crimson 625 loaded on commercial beads served as the donor and acceptor, respectively. Binding of the target DNA to the single bead sensor induces G-quadruplex stretching, resulting in a decrease in fluorescence energy transfer. G-rich telomere sequences formed a G-quadruplex structure in the presence of ZnTCPP, as demonstrated by the detection of two strong donor and acceptor signals. The sensitivity of the sensor was 1 fM. Under optimized conditions using a polydimethylsiloxane microfluidic device, we measured the number of sensor beads by direct counting. By controlling the flow rate via the probe volume, one sensing experiment can be completed in 5 minutes. Based on these results, we propose a new parameter-dependability (RS)-as a quantitative measure to judge the quality of a bio-sensor. This parameter is based on the ratio of the sensor and sensing sample fluorescence signals. This parameter can range from 0.1 to 100, where a value of 10 represents an optimized bio-sensor.


Assuntos
Técnicas Biossensoriais , DNA , Transferência Ressonante de Energia de Fluorescência , Quadruplex G , Telômero/química , Fluorescência
19.
Water Res ; 256: 121646, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38657309

RESUMO

Sewage treatment processes are a critical anthropogenic source of bioaerosols and may present significant health risks to plant workers. Compared with the specialization and scale of urban sewage treatment, many decentralized treatment models are flexible and extensive. These treatment facilities are usually close to residential areas owing to the pipe network layout and other restrictions. Bioaerosols generated by these facilities may present a serious and widespread occupational and non-occupational exposure risk to nearby residents, particularly the elderly and children. An understanding of the characteristics and exposure risks of bioaerosols produced during decentralized sewage treatment is lacking. We compared bioaerosol emission characteristics and potential exposure risks under four decentralized sewage discharge methods and treatment models: small container collection (SCC), open-channel discharge (OCD), single household/combined treatment (SHCT), and centralized treatment (CT) in northwest China. The OCD mode had the highest bioaerosol production, whereas the CT mode had the lowest. The OCD model contained the most pathogenic bacterial species, up to 43 species, including Sphingomonas, Pseudomonas, Cladosporium, and Alternaria. Risk assessments indicated bioaerosol exposure was lower in the models with sewage treatment (SHCT and CT) than in those without (SCC and OCD). Different populations exhibited large variations in potential risks owing to differences in time spent indoors and outdoors. The highest risk was observed in males exposed to the SCC model. This study provides a theoretical basis and theories for the future joint prevention and control of the bioaerosol exposure risk from decentralized sewage treatment.


Assuntos
Aerossóis , Microbiologia do Ar , Esgotos , Esgotos/microbiologia , Eliminação de Resíduos Líquidos , China , Humanos , Medição de Risco , Bactérias
20.
Environ Pollut ; 324: 121338, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36842620

RESUMO

In rural China, the release of bioaerosols containing pathogens from solid waste dumps poses a potential health risk to the local population. Here, we sampled bioaerosols from rural solid waste-treatment in four provinces of northwest China to investigate their emission and dispersion characteristics in order to provide a scientific basis for control and risk reduction of bioaerosols released from rural sanitation facilities. The airborne bioaerosol concentrations and particle size distributions were calculated using an Anderson six-stage airborne microbial sampler and counting with its internal Petri dish culture. High-throughput sequencing was used to characterize the microbial composition at different sampling sites and to explore possible influencing factors, while the health risk associated with exposure was estimated based on average daily dose-rate. The highest concentration point values of bacteria and fungi in bioaerosols near the solid waste were 63,617 ± 15,007 and 8044 ± 893 CFU/m³, respectively. Furthermore, the highest concentration point values of Enterobacteriaceae was 502 ± 35 CFU/m³. Most bioaerosols were coarse particles larger than 3.3 µm. Potentially pathogenic genera of winter-indicator species detected in the air were primarily Delftia, Rhodococcus and Aspergillus. The composition of solid waste and environmental conditions are important factors in determining the characteristics of bioaerosols. Local residents are exposed to bioaerosols mainly through inhalation. Children are at a particularly high risk of exposure through both inhalation and skin contact. The results of this study show that bioaerosols in the vicinity of rural solid waste dumps pose a health risk to the surrounding population. More suitable risk assessment criteria for rural areas should be established, and corresponding control and protection measures should be taken from three aspects: generation source and transmission pathway, as well as the recipient.


Assuntos
Microbiologia do Ar , Resíduos Sólidos , Criança , Humanos , Aerossóis/análise , Bactérias , Fungos , China , Monitoramento Ambiental
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