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1.
J Mol Cell Cardiol ; 192: 48-64, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38734060

RESUMO

INTRODUCTION: Chronic immunopathology contributes to the development of heart failure after a myocardial infarction. Both T and B cells of the adaptive immune system are present in the myocardium and have been suggested to be involved in post-MI immunopathology. METHODS: We analyzed the B and T cell populations isolated from previously published single cell RNA-sequencing data sets (PMID: 32130914, PMID: 35948637, PMID: 32971526 and PMID: 35926050), of the mouse and human heart, using differential expression analysis, functional enrichment analysis, gene regulatory inferences, and integration with autoimmune and cardiovascular GWAS. RESULTS: Already at baseline, mature effector B and T cells are present in the human and mouse heart, having increased activity in transcription factors maintaining tolerance (e.g. DEAF1, JDP2, SPI-B). Following MI, T cells upregulate pro-inflammatory transcript levels (e.g. Cd11, Gzmk, Prf1), while B cells upregulate activation markers (e.g. Il6, Il1rn, Ccl6) and collagen (e.g. Col5a2, Col4a1, Col1a2). Importantly, pro-inflammatory and fibrotic transcription factors (e.g. NFKB1, CREM, REL) remain active in T cells, while B cells maintain elevated activity in transcription factors related to immunoglobulin production (e.g. ERG, REL) in both mouse and human post-MI hearts. Notably, genes differentially expressed in post-MI T and B cells are associated with cardiovascular and autoimmune disease. CONCLUSION: These findings highlight the varied and time-dependent dynamic roles of post-MI T and B cells. They appear ready-to-go and are activated immediately after MI, thus participate in the acute wound healing response. However, they subsequently remain in a state of pro-inflammatory activation contributing to persistent immunopathology.


Assuntos
Linfócitos B , Infarto do Miocárdio , Miocárdio , Análise de Sequência de RNA , Análise de Célula Única , Infarto do Miocárdio/genética , Infarto do Miocárdio/imunologia , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Humanos , Animais , Camundongos , Miocárdio/metabolismo , Miocárdio/patologia , Linfócitos B/metabolismo , Linfócitos B/imunologia , Linfócitos T/metabolismo , Linfócitos T/imunologia , Imunidade Adaptativa/genética , Regulação da Expressão Gênica , Perfilação da Expressão Gênica , Transcriptoma/genética , Transcrição Gênica , Estudo de Associação Genômica Ampla
2.
Brief Bioinform ; 23(6)2022 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-36209413

RESUMO

MOTIVATION: Single-cell/nuclei RNA-sequencing (scRNA-seq) technologies can simultaneously quantify gene expression in thousands of cells across the genome. However, the majority of the noncoding RNAs, such as microRNAs (miRNAs), cannot currently be profiled at the same scale. MiRNAs are a class of small noncoding RNAs and play an important role in gene regulation. MiRNAs originate from the processing of primary transcripts, known as primary-microRNAs (pri-miRNAs). The pri-miRNA transcripts, independent of their cognate miRNAs, can also function as long noncoding RNAs, code for micropeptides or even interact with DNA, acting like enhancers. Therefore, it is apparent that the significance of scRNA-seq pri-miRNA profiling expands beyond using pri-miRNA as proxies of mature miRNAs. However, there are no computational methods that allow profiling and quantification of pri-miRNAs at the single-cell-type resolution. RESULTS: We have developed a simple yet effective computational framework to profile pri-MiRNAs from single-cell RNA-sequencing datasets (PPMS). Based on user input, PPMS can profile pri-miRNAs at cell-type resolution. PPMS can be applied to both newly produced and publicly available datasets obtained via single cell or single-nuclei RNA-seq. It allows users to (i) investigate the distribution of pri-miRNAs across cell types and cell states and (ii) establish a relationship between the number of cells/reads sequenced and the detection of pri-miRNAs. Here, to demonstrate its efficacy, we have applied PPMS to publicly available scRNA-seq data generated from (i) individual chambers (ventricles and atria) of the human heart, (ii) human pluripotent stem cells during their differentiation into cardiomyocytes (the heart beating cells) and (iii) hiPSCs-derived cardiomyocytes infected with severe acute respiratory syndrome coronavirus 2.


Assuntos
COVID-19 , MicroRNAs , Pequeno RNA não Traduzido , Humanos , Processamento Pós-Transcricional do RNA , Regulação da Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo
3.
J Opt Soc Am A Opt Image Sci Vis ; 41(3): A47-A54, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437429

RESUMO

In this study, we proposed a holographic identity verification encryption system that integrates face recognition, air-writing, and the multiple point cloud gridding encryption (M-PCGE) method to ensure multi-level security for objects. The experimental results show that the M-PCGE algorithm proposed in this paper achieves image encryption and decryption quickly with a high degree of restoration, and the security is verified.

4.
Opt Express ; 31(2): 1641-1655, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785195

RESUMO

At present, a real objects-based full-color holographic system usually uses a digital single-lens reflex (DSLR) camera array or depth camera to collect data. It then relies on a spatial light modulator to modulate the input light source for the reconstruction of the 3-D scene of the real objects. However, the main challenges the high-quality holographic 3-D display faced were the limitation of generation speed and the low accuracy of the computer-generated holograms. This research generates more effective and accurate point cloud data by developing an RGB-D salient object detection model in the acquisition unit. In addition, a divided point cloud gridding method is proposed to enhance the computing speed of hologram generation. In the RGB channels, we categorized each object point into depth grids with identical depth values. The depth girds are divided into M × N parts, and only the effective parts will be calculated. Compared with traditional methods, the calculation time is dramatically reduced. The feasibility of our proposed approach is established through experiments.

5.
Chemistry ; 29(24): e202203921, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-36694374

RESUMO

Catalytic hydrogen peroxide (H2 O2 ) generation from oxygen and water enables a sustainable environment to operate in an effective and green energy-to-chemical conversion way, which has attracted increasing interest in the fields of energy production and environment treatment. In light of this, tremendous progresses and developments have been made during the past decades in catalytic H2 O2 production for pollutant removal from three perspectives including photocatalysis, electrocatalysis or chemical activation. Herein, we critically review the state-of-the-art developments over various procedures of H2 O2 generation and its further application, with the existence of photocatalysts, electrocatalysts, and catalysts, respectively. Benefiting from extensively experimental and theoretical investigations, the performance and stability of H2 O2 generation and its utilization can be maneuvered by devising catalytic platform based on numerous catalysts with predominant electronic, chemical and physical properties, which endow the catalysts with efficient electrons transportation, abundant active sites, and sufficient oxygen adsorption for H2 O2 generation. Furthermore, this review also discusses the formation mechanism of H2 O2 by 2e-ORR and 2e-WOR, as well as its functional process of activating and removing pollutants, and summarizes the design principles of various catalysts by focusing on the formation of H2 O2 . We finally highlight the specific challenges and prospects related to the utilization of catalysts and envision the possible future development trends in the fields of pollutant removal.

6.
J Opt Soc Am A Opt Image Sci Vis ; 40(4): B1-B7, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37132944

RESUMO

In this study, a 3D salient object detection model is built at the acquisition step in the full-color holographic system, and a deep network architecture U 2-reverse attention and residual learning (RAS) algorithm is proposed for salient object detection to obtain more efficient and accurate point cloud information. In addition, we also use the point cloud gridding method to improve the hologram generation speed. Compared with the traditional region of interest method, RAS algorithm, and U 2-Net algorithm, the computational complexity is significantly reduced. Finally, the feasibility of this method is proved by experiments.

7.
Molecules ; 28(14)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37513340

RESUMO

Five ester-bonded gemini quaternary ammonium surfactants C12-En-C12 (n = 2, 4, 6), with a flexible spacer group, and C12-Bm-C12 (m = 1, 2), with rigid benzene spacers, were synthesized via a two-step reaction and analyzed. Furthermore, the effects of the spacer structure, spacer length and polymerization degree on the self-aggregation, antimicrobial activity and cytotoxicity of C12-En-C12 and C12-Bm-C12 and their corresponding monomer N-dodecyl-N,N,N-trimethyl ammonium chloride DTAC were investigated. The results showed that C12-En-C12 and C12-Bm-C12 had markedly lower critical micellar concentration (CMC) values and lower surface tension than DTAC. Moreover, the CMC values of C12-En-C12 and C12-Bm-C12 decreased with increasing spacer length. In the case of equivalent chain length, the rigidity and steric hindrance of phenylene and 1,4-benzenediyl resulted in larger CMC values for C12-Bm-C12 than for C12-En-C12. The antibacterial ability of C12-En-C12 and C12-Bm-C12 was assessed using Escherichia coli (E. coli) and Staphylococcus albus (S. aureus) based on minimum inhibitory concentrations (MICs). Furthermore, C12-En-C12 and C12-Bm-C12 exhibited higher antimicrobial activity than DTAC and had stronger function toward S. aureus than E. coli. The antimicrobial activity was enhanced by increasing the spacer chain length and decreased with the increased rigidity of the spacers. The cytotoxic effects of C12-En-C12 and C12-Bm-C12 in cultured Hela cells were evaluated by the standard CCK8 method based on half-maximal inhibitory concentration (IC50). The cytotoxicity of C12-En-C12 and C12-Bm-C12 was significantly lower than alkanediyl-α,ω-bis(dimethyldodecylammonium) bromide surfactants and DTAC. The spacer structure and the spacer length could induce significant cytotoxic effects on Hela cells. These findings indicate that the five ester-bonded GQASs have stronger antibacterial activity and lower toxicity profile, and thus can be used in the pharmaceutical industry.


Assuntos
Escherichia coli , Sais , Humanos , Sais/farmacologia , Células HeLa , Staphylococcus aureus , Compostos de Amônio Quaternário/farmacologia , Compostos de Amônio Quaternário/química , Antibacterianos/farmacologia , Tensoativos/farmacologia , Tensoativos/química
8.
Lipids Health Dis ; 21(1): 15, 2022 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-35065639

RESUMO

BACKGROUND: Bile acids (BAs) not only play an important role in lipid metabolism and atherosclerosis but also have antiapoptotic and neuroprotective effects. However, few studies have focused on the relationship of the total bile acid (TBA) levels with the severity and prognosis of acute ischemic stroke (AIS). OBJECTIVES: The aim of this study was to investigate the potential associations of the fasting serum TBA levels on admission with the stroke severity, in-hospital complication incidence and 3 -month all-cause mortality in patients with AIS. METHODS: A total of 777 consecutive AIS patients were enrolled in this study and were divided into four groups according to the quartiles of the serum TBA levels on admission. Univariate and multivariate logistic regression analyses were used to explore the relationship between the fasting TBA levels and the stroke severity, in-hospital complications, and 3-month mortality in AIS patients. RESULTS: Patients in group Q3 had the lowest risk of severe AIS (NIHSS > 10) regardless of the adjustments for confounders (P < 0.05). During hospitalization, 115 patients (14.8%) had stroke progression (NIHSS score increased by ≥ 2), and 222 patients (28.6%) developed at least one complication, with no significant difference among the four groups (P > 0.05). There was no significant difference in the incidence of pneumonia, urinary tract infection (UTI), hemorrhagic transformation (HT), gastrointestinal bleeding (GIB), seizures or renal insufficiency (RI) among the four groups (P > 0.05). A total of 114 patients (14.7%) died from various causes (including in-hospital deaths) at the 3-month follow-up, including 42 (21.3%), 26 (13.3%), 19 (9.9%) and 27 (13.9%) patients in groups Q1, Q2, Q3 and Q4 respectively, with significant differences (P = 0.013). After adjusting for confounding factors, the risk of death decreased (P -trend < 0.05) in groups Q2, Q3, and Q4 when compared with group Q1, and the OR values were 0.36 (0.16-0.80), 0.30 (0.13-0.70), and 0.29 (0.13-0.65), respectively. CONCLUSIONS: TBA levels were inversely associated with the 3-month mortality of AIS patients but were not significantly associated with the severity of stroke or the incidence of complications.


Assuntos
Ácidos e Sais Biliares/sangue , AVC Isquêmico/mortalidade , Idoso , Feminino , Humanos , AVC Isquêmico/sangue , AVC Isquêmico/diagnóstico , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente , Prognóstico , Fatores de Risco
9.
Angew Chem Int Ed Engl ; 60(6): 2903-2908, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33098249

RESUMO

It is important to develop self-producing reactive oxygen species (ROSs) systems and maintain the continuous and effective degradation of organic pollutants. Herein, for the first time, a system of ultrasound-treated CoS2-x mixed with Fe2+ is constructed to sustainably release singlet oxygen (1 O2 ) for the effective degradation of various organic pollutants, including dyes, phenols, and antibiotics. Ultrasonic treatment produces defects on the surface of CoS2 which promote the production of ROSs and the circulation of Fe3+ /Fe2+ . With the help of Co4+ /Co3+ exposed on the surface of CoS2-x , the directional conversion of superoxide radical (. O2- ) to 1 O2 is realized. The CoS2-x /Fe2+ system can degrade organic pollutants efficiently for up to 30 days, which is significantly better than the currently recognized CuPx system (<3 days). Therefore, CoS2-x provides a new choice for the long-term remediation of organic pollutants in controlling large area river pollution.


Assuntos
Cobalto/química , Poluentes Químicos da Água/química , Catálise , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Ferro/química , Oxirredução , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo , Sonicação , Superóxidos/química , Superóxidos/metabolismo , Poluentes Químicos da Água/metabolismo
10.
Environ Toxicol ; 35(10): 1033-1042, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32478940

RESUMO

Widespread occupational and environmental exposure to benzene is unavoidable and poses a public health threat. Studies of potential interventions to prevent or relieve benzene toxicity are, thus, essential. Research has shown l-carnitine (LC) has beneficial effects against various pathological processes and diseases. LC possesses antioxidant activities and participates in fatty acid oxidation (FAO). In this study, we investigated whether 1,4-benzoquinone (1,4-BQ) affects LC levels and the FAO pathway, as well as analyzed the influence of LC on the cytotoxic effects of 1,4-BQ. We found that 1,4-BQ significantly decreased LC levels and downregulated Cpt1a, Cpt2, Crat, Hadha, Acaa2, and Acadvl mRNA expression in K562 cells. Subsequent assays confirmed that 1,4-BQ decreased cell viability and increased apoptosis and caspase-3, -8, and -9 activities. It also induced obvious oxidative stress and DNA damage, including an increase in the levels of reactive oxygen species and malondialdehyde, tail DNA%, and olive tail moment. Additionally, the mitochondrial membrane potential was significantly reduced. Cotreatment with LC (500 µmol/L) relieved these alterations by reducing oxidative stress and increasing the protein expression levels of Cpt1a and Hadha, particularly in the 20 µmol/L 1,4-BQ group. Thus, our results demonstrate that 1,4-BQ causes cytotoxicity, reduces LC levels, and downregulates the FAO genes. In contrast, LC exhibits protective effects against 1,4-BQ-induced apoptosis and DNA damage by decreasing oxidative stress and promoting the FAO pathway.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Benzoquinonas/toxicidade , Carnitina/farmacologia , Dano ao DNA/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Carnitina/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Células K562 , Metabolismo dos Lipídeos/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
11.
Angew Chem Int Ed Engl ; 59(33): 13968-13976, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32386108

RESUMO

3D-MoS2 can adsorb organic molecules and provide multidimensional electron transport pathways, implying a potential application for environment remediation. Here, we study the degradation of aromatic organics in advanced oxidation processes (AOPs) by a 3D-MoS2 sponge loaded with MoS2 nanospheres and graphene oxide (GO). Exposed Mo4+ active sites on 3D-MoS2 can significantly improve the concentration and stability of Fe2+ in AOPs and keep the Fe3+ /Fe2+ in a stable dynamic cycle, thus effectively promoting the activation of H2 O2 /peroxymonosulfate (PMS). The degradation rate of organic pollutants in the 3D-MoS2 system is about 50 times higher than without cocatalyst. After a 140 L pilot-scale experiment, it still maintains high efficiency and stable AOPs activity. After 16 days of continuous reaction, the 3D-MoS2 achieves a degradation rate of 120 mg L-1 antibiotic wastewater up to 97.87 %. The operating cost of treating a ton of wastewater is only US$ 0.33, suggesting huge industrial applications.


Assuntos
Dissulfetos/química , Poluentes Ambientais/química , Molibdênio/química , Adsorção , Catálise , Transporte de Elétrons , Estudos de Viabilidade , Oxirredução , Projetos Piloto
12.
Environ Sci Technol ; 53(16): 9725-9733, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31331171

RESUMO

As an important reactive oxygen species (ROS) with selective oxidation, singlet oxygen (1O2) has wide application prospects in biology and the environment. However, the mechanism of 1O2 formation, especially the conversion of superoxide radicals (·O2-) to 1O2, has been a great controversy. This process is often disturbed by hydroxyl radicals (·OH). Here, we develop a molybdenum cocatalytic Fenton system, which can realize the transformation from ·O2- to 1O2 on the premise of minimizing ·OH. The Mo0 exposed on the surface of molybdenum powder can significantly improve the Fe3+/Fe2+ cycling efficiency and weaken the production of ·OH, leading to the generation of ·O2-. Meanwhile, the exposed Mo6+ can realize the transformation of ·O2- to 1O2. The molybdenum cocatalytic effect makes the conventional Fenton reaction have high oxidation activity for the remediation of organic pollutants and prompts the inactivation of Staphylococcus aureus, as well as the adsorption and reduction of heavy metal ions (Cu2+, Ni2+, and Cr6+). Compared with iron powder, molybdenum powder is more likely to promote the conversion from Fe3+ to Fe2+ during the Fenton reaction, resulting in a higher Fe2+/Fe3+ ratio and better activity regarding the remediation of organics. Our findings clarify the transformation mechanism from ·O2- to 1O2 during the Fenton-like reaction and provide a promising REDOX Fenton-like system for water treatment.


Assuntos
Molibdênio , Superóxidos , Peróxido de Hidrogênio , Ferro , Oxirredução , Oxigênio Singlete
13.
Environ Sci Technol ; 52(19): 11297-11308, 2018 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-30180549

RESUMO

The greatest problem in the Fe(II)/H2O2 Fenton reaction is the low production of ·OH owing to the inefficient Fe(III)/Fe(II) cycle and the low decomposition efficiency of H2O2 (<30%). Herein, we report a new discovery regarding the significant co-catalytic effect of WS2 on the decomposition of H2O2 in a photoassisted Fe(II)/H2O2 Fenton system. With the help of WS2 co-catalytic effect, the H2O2 decomposition efficiency can be increased from 22.9% to 60.1%, such that minimal concentrations of H2O2 (0.4 mmol/L) and Fe2+ (0.14 mmol/L) are necessary for the standard Fenton reaction. Interestingly, the co-catalytic Fenton strategy can be applied to the simultaneous oxidation of phenol (10 mg/L) and reduction of Cr(VI) (40 mg/L), and the corresponding degradation and reduction rates can reach up to 80.9% and 90.9%, respectively, which are much higher than the conventional Fenton reaction (52.0% and 31.0%). We found that the expose reductive W4+ active sites on the surface of WS2 can greatly accelerate the rate-limiting step of Fe3+/Fe2+ conversion, which plays the key role in the decomposition of H2O2 and the reduction of Cr(VI). Our discovery represents a breakthrough in the field of inorganic catalyzing AOPs and greatly advances the practical utility of this method for environmental applications.


Assuntos
Peróxido de Hidrogênio , Fenol , Cromo , Ferro , Oxirredução , Fenóis
14.
Artigo em Inglês | MEDLINE | ID: mdl-38970420

RESUMO

Significance: Herbal medicines have a long history of comprehensive cancer treatment through various posttranslational modifications (PTMs). Recently, emerging evidence revealed that dysregulation of reactive oxygen species (ROS) and ROS-regulated signaling pathways influence cancer initiation, growth, and progression in a paradoxical role with either low levels or increasing levels of basal ROS. However, ROS-triggered modifications of target proteins in the face of ROS-mediated signal transduction are not fully understood in the anticancer therapies of herbal medicines. In this review, we briefly introduce the PTM-dependent regulations of herbal medicines, and then focus on the current ideals that targeting ROS-dependent PTMs via antioxidant and redox signaling pathways can provide a promising strategy in herbal-based anticancer effects. Recent Advances: Advanced development in highly sensitive mass spectrometry-based techniques has helped utilize ROS-triggered protein modifications in numerous cancers. Accumulating evidence has been achieved in laboratory to extensively ascertain the biological mechanism of herbal medicines targeting ROS in cancer therapy. Two general mechanisms underlining ROS-induced cell signaling include redox state and oxidative modification of target protein, indicating a new perspective to comprehend the intricate dialogues between herbal medicines and cancer cellular contexts. Critical Issues: Complex components of herbal medicines limit the benefits of herbal-based cancer therapies. In this review, we address that ROS-dependent PTMs add a layer of proteomic complexity to the cancer through altering the protein structure, expression, function, and localization. Elaborating ROS-triggered PTMs implicated in cell signaling, apoptosis, and transcriptional regulation function, and the possible cellular signaling, has provided important information about the contribution of many ROS targeting herbal therapies in anticancer effects. Continued optimization of proteomic strategies for PTM analysis in herbal medicines is also briefly discussed. Future Directions: Rigorous evaluations of herbal medicines and proteomic strategies are necessary to explore the aberrant regulation of ROS-triggered antioxidant and redox signaling contributing to the novel protein targets and herbal-associated pharmacological issues. These efforts will eventually help develop more herbal drugs as modern therapeutic agents.

15.
Micromachines (Basel) ; 14(2)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36838050

RESUMO

In this paper, silver nanoparticles (AgNPs) were successfully green-synthesized for the first time using Hedysarum polysaccharide (HPS) as a reducing agent, stabilizer, and modifier (HPS-AgNP). Thiamazole could induce the aggregation of HPS-AgNPs in the residue on a cellulose membrane. A syringe paper-based analytical device was creatively established to ensure the tightness, stability, and good repeatability of the test. The color information remaining on the cellulose membrane was converted into gray values using ImageJ software. Hence, the linear regression curve for thiamazole was established as y = 1 + 0.179x with a detection limit (LOD) of 24.6 nM in the relatively wide range of 0.1~10 µM. This syringe paper-based analytical device was successfully applied to the biological samples.

16.
Anal Methods ; 14(6): 643-651, 2022 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-35080529

RESUMO

In this study, a safe, rapid, and environment-friendly green synthesis of silver nanoparticles using the alcohol extract of Radix Hedysari (RH-AgNPs) was developed, the alcohol extract of Radix Hedysari (RH) acted as the reducing agent, stabilizer, and modifier. The main components of RH were determined using high-performance liquid chromatography (HPLC). The particle size and morphology of RH-AgNPs were optimized and characterized by a series of techniques. The size distribution, zeta potential, element distribution, and crystalline nature of RH-AgNPs were all determined. It was indicated that RH-AgNPs showed great sensitivity for lead ion (Pb2+) detection with a limit of detection (LOD) of 1.5 µM with a wide range of 10-500 µM. The selectivity was also explored for common metal ions. RH-AgNPs were then applied to the detection of Pb2+ in spiked Yellow River samples, and the possible mechanism is based on the crosslinking reaction between the hydroxide radical, carboxylate radical and Pb2+.


Assuntos
Colorimetria , Chumbo/isolamento & purificação , Nanopartículas Metálicas , Prata , Colorimetria/métodos , Química Verde , Nanopartículas Metálicas/química , Rios , Prata/química
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 270: 120840, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35007909

RESUMO

A novel photoluminescent Hcy-AuNCs has been developed through one-pot reduction method, to establish a tobramycin sensing by second-order scattering (SOS). Hcy-AuNCs could spontaneously assemble to small-scaled aggregation, resulting in remarkable intensity enhancement of scattered luminescence signals. The luminescence of Hcy-AuNCs could be clearly observed under ultraviolet lamp, when excited at 365 nm, a significant luminescent intensity at 741 nm was monitored in SOS spectra. The introduction of AuNPs would cause large-scaled aggregation of Hcy-AuNCs that was rapidly settled in the solution, resulting in the decrease of SOS intensity. Besides, the non-radiative energy transfer between AuNPs and Hcy-AuNCs would also reduce the luminescent intensity. However, the addition of tobramycin would cause the aggregation of AuNPs due to the electrostatic and covalent bonding between AuNPs and tobramycin, thus eliminating the interference of AuNPs. The luminescence of Hcy-AuNCs reappeared, exhibiting an optical response toward tobramycin. The good linearity was obtained in a wide range from 4 nM to 300 nM with a low detection limit of 0.27 nM. The selectivity was acceptable toward different types of antibiotics. Finally, the proposed method was successfully applied to the widely used tobramycin eye drops.


Assuntos
Ouro , Nanopartículas Metálicas , Homocistina , Eletricidade Estática , Tobramicina
18.
Brain Behav ; 12(7): e2675, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35748095

RESUMO

OBJECTIVES: We aimed to explore the association between the baseline hypersensitive C-reactive protein-albumin ratio (CAR) and stroke-associated pneumonia (SAP) during hospitalization and the short-term prognosis in patients with acute ischemic stroke (AIS). METHODS: We enrolled 766 patients with AIS and collected their admission baseline characteristics, including their National Institutes of Health Stroke Scale score, CAR, age, atrial fibrillation, dysphagia, sex, stroke severity (A2 DS2 ) score, and other information. The occurrence of SAP within 7 days after stroke, length of hospital stay, and physical condition at discharge were also recorded. The patients' Modified Rankin Scale (mRS) scores and mortality 3 months after AIS were further evaluated at follow-up. All patients were divided into four groups based on the quartiles of the admission CAR (Q1 <1.3, Q2 1.3-3.7, Q3 3.7-9.3, Q4 ≥9.3). RESULTS: During hospitalization, 92 (11.9%) patients were diagnosed with SAP. The patients with SAP had a higher CAR than the non-SAP patients (p < .001). In the multivariate-adjusted model, the patients in the Q3 and Q4 groups had a higher SAP risk (aOR was 5.21 and 17.72, p-trend < .001) than those in the lowest quartile. The area under the curve for the CAR's ability to predict SAP was 0.810 in the receiver operating characteristic curve analysis and had a similar predictive efficacy as the A2 DS2  score (p <.05). The length of stay in the SAP group was almost the same as that in the non-SAP group, but the clinical outcomes were worse at discharge and at the 3-month follow-up in the SAP group. In addition, the patients in the higher CAR quartiles at admission were more likely to have poorer clinical outcomes. CONCLUSIONS: Patients with AIS with a high CAR at admission are more likely to develop SAP during hospitalization and have poor short-term clinical outcomes. These findings might help to timely identify patients at high risk of SAP and provide a basis for further research on prophylactic antibiotic therapy.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Pneumonia , Acidente Vascular Cerebral , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/terapia , Proteína C-Reativa , Humanos , AVC Isquêmico/complicações , AVC Isquêmico/terapia , Pneumonia/epidemiologia , Pneumonia/terapia , Prognóstico , Fatores de Risco , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia
19.
Chem Commun (Camb) ; 58(8): 1131-1134, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-34981082

RESUMO

It is a challenge to effectively load proton carriers in COFs to improve their proton conductivity. Herein, we report a series of COF-based composites, PANa@UCOF-x (PANa: sodium polyacrylate, x: weight percentage of PANa), which were prepared by coating different proportions of superabsorbent PANa on the COF surface based on an in situ reaction strategy. Since PANa can greatly enhance the enrichment of water molecules in one-dimensional (1D) channels of COFs, these COF-based composites exhibit superprotonic conduction. At 80 °C and 95% relative humidity (RH), the proton conductivity of PANa@UCOF-10, PANa@UCOF-28 and PANa@UCOF-40 reaches 1.6 × 10-2, 5.1 × 10-2, and 1.1 × 10-1 S cm-1, respectively, which is 4-5 orders of magnitude higher than 7.4 × 10-7 S cm-1 of the original UCOF. This work not only develops a new method to improve the water content of the COF channels, but also proves the important role of ordered channels in constructing effective proton conduction pathways.

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