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1.
Front Nutr ; 11: 1256832, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774261

RESUMO

Background: Observational studies have found associations between blood cell traits and inflammatory bowel diseases (IBDs), whereas the causality and dose-effect relationships are still undetermined. Methods: Two-sample Mendelian randomization (MR) analyses using linear regression approaches, as well as Bayesian model averaging (MR-BMA), were conducted to identify and prioritize the causal blood cell traits for Crohn's disease (CD) and ulcerative colitis (UC). An observational study was also performed using restricted cubic spline (RCS) to explore the relationship between important blood cell traits and IBDs. Results: Our uvMR analysis using the random effects inverse variance weighted (IVW) method identified eosinophil (EOS) as a causal factor for UC (OR = 1.36; 95% CI: 1.13, 1.63). Our MR-BMA analysis further prioritized that high level of lymphocyte (LYM) decreased CD risk (MIP = 0.307; θ^MACE = -0.059; PP = 0.189; θ^λ = -0.173), whereas high level of EOS increased UC risk (MIP = 0.824; θ^MACE = 0.198; PP = 0.627; θ^λ = 0.239). Furthermore, the observational study clearly depicts the nonlinear relationship between important blood cell traits and the risk of IBDs. Conclusion: Using MR approaches, several blood cell traits were identified as risk factors of CD and UC, which could be used as potential targets for the management of IBDs. Stratified genome-wide association studies (GWASs) based on the concentration of traits would be helpful owing to the nonlinear relationships between blood cell traits and IBDs, as demonstrated in our clinical observational study. Together, these findings could shed light on the clinical strategies applied to the management of CD and UC.

2.
J Biochem Mol Toxicol ; 38(1): e23626, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38229315

RESUMO

Immunoglobulin (Ig) G4 has a distinctive nature, and its involvement in autoimmune disorders is a subject of ongoing debate and uncertainty. A growing body of evidence indicates that IgG4 may play a pathogenic role in the development of systemic lupus erythematosus (SLE). The IgG4 autoantibodies have the capability to bind autoantigens in a competitive manner with other Ig classes, thereby forming immune complexes (ICs) that are noninflammatory in nature. This is due to the low affinity of IgG4 for both the Fc receptors and the C1 complement molecule, which results in a diminished inflammatory response in individuals with SLE. The present study aims to elucidate the significance of IgG4 in SLE. The present discourse pertains to the nascent and suggested modalities through which IgG4 might participate in the pathogenesis of SLE and the potential ramifications for therapeutic interventions in SLE.


Assuntos
Imunoglobulina G , Lúpus Eritematoso Sistêmico , Humanos , Lúpus Eritematoso Sistêmico/terapia , Lúpus Eritematoso Sistêmico/patologia , Autoanticorpos
3.
Analyst ; 149(2): 304-349, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38051130

RESUMO

With the rapid development of fluorescent nanoparticles (FNPs), such as CDs, QDs, and MOFs, the construction of FNP-based probes has played a key role in improving chemical sensors. Ratiometric fluorescent probes exhibit distinct advantages, such as resistance to environmental interference and achieving visualization. Thus, FNP-based dual-emission ratiometric fluorescent probes (DRFPs) have rapidly developed in the field of metal ion and small molecule detection in the past few years. In this review, firstly we introduce the fluorescence sensing mechanisms; then, we focus on the strategies for the fabrication of DRFPs, including hybrid FNPs, single FNPs with intrinsic dual emission and target-induced new emission, and DRFPs based on auxiliary nanoparticles. In the section on hybrid FNPs, methods to assemble two types of FNPs, such as chemical bonding, electrostatic interaction, core satellite or core-shell structures, coordination, and encapsulation, are introduced. In the section on single FNPs with intrinsic dual emission, methods for the design of dual-emission CDs, QDs, and MOFs are discussed. Regarding target-induced new emission, sensitization, coordination, hydrogen bonding, and chemical reaction induced new emissions are discussed. Furthermore, in the section on DRFPs based on auxiliary nanoparticles, auxiliary nanomaterials with the inner filter effect and enzyme mimicking activity are discussed. Finally, the existing challenges and an outlook on the future of DRFP are presented. We sincerely hope that this review will contribute to the quick understanding and exploration of DRFPs by researchers.

4.
Front Oncol ; 13: 1195392, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37534253

RESUMO

Acute myeloid leukemia (AML) is a complex mixed entity composed of malignant tumor cells, immune cells and stromal cells, with intra-tumor and inter-tumor heterogeneity. Single-cell RNA sequencing enables a comprehensive study of the highly complex tumor microenvironment, which is conducive to exploring the evolutionary trajectory of tumor cells. Herein, we carried out comprehensive analyses of aggrephagy-related cell clusters based on single-cell sequencing for patients with acute myeloid leukemia. A total of 11 specific cell types (T, NK, CMP, Myeloid, GMP, MEP, Promono, Plasma, HSC, B, and Erythroid cells) using t-SNE dimension reduction analysis. Several aggrephagy-related genes were highly expressed in the 11 specific cell types. Using Monocle analysis and NMF clustering analysis, six aggrephagy-related CD8+ T clusters, six aggrephagy-related NK clusters, and six aggrephagy-related Mac clusters were identified. We also evaluated the ligand-receptor links and Cell-cell communication using CellChat package and CellChatDB database. Furthermore, the transcription factors (TFs) of aggrephagy-mediated cell clusters for AML were assessed through pySCENIC package. Prognostic analysis of the aggrephagy-related cell clusters based on R package revealed the differences in prognosis of aggrephagy-mediated cell clusters. Immunotherapy of the aggrephagy-related cell clusters was investigated using TIDE algorithm and public immunotherapy cohorts. Our study revealed the significance of aggrephagy-related patterns in tumor microenvironment, prognosis, and immunotherapy for AML.

5.
Pathol Res Pract ; 248: 154677, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37467636

RESUMO

Angiogenesis has been recognized as a critical factor in developing solid tumors and hematological malignancies. How angiogenesis affects the molecular pathways in malignancies is still a mystery. The angiopoietin family, one of the known molecular mediators for angiogenesis, encourages angiogenesis by attaching to Tie receptors on cell surfaces. Angiopoietin, Tie, and particularly the molecular pathways they mediate have all been the subject of recent studies that have established their diagnostic, prognostic, and therapeutic potential. Here, we've reviewed the function of molecular pathways impacted by the Angiogenin and Tie system in hematological malignancies.


Assuntos
Neoplasias Hematológicas , Neoplasias , Humanos , Angiopoietinas , Receptor TIE-2/metabolismo , Angiopoietina-1/metabolismo , Angiopoietina-2/metabolismo
6.
Metabolites ; 13(6)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37367888

RESUMO

Inflammatory bowel diseases (IBDs), including Crohn's disease (CD) and ulcerative colitis (UC), have become a global health problem with a rapid growth of incidence in newly industrialized countries. Observational studies have recognized associations between blood lipid traits and IBDs, but the causality still remains unclear. To determine the causal effects of blood lipid traits, including triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) on IBDs, two-sample Mendelian randomization (MR) analyses were conducted using the summary-level genome-wide association study (GWAS) statistics of blood lipid traits and IBDs. Our univariable MR using multiplicative random-effect inverse-variance weight (IVW) method identified TC (OR: 0.674; 95% CI: 0.554, 0.820; p < 0.00625) and LDL-C (OR: 0.685; 95% CI: 0.546, 0.858; p < 0.00625) as protective factors of UC. The result of our multivariable MR analysis further provided suggestive evidence of the protective effect of TC on UC risk (OR: 0.147; 95% CI: 0.025, 0.883; p < 0.05). Finally, our MR-BMA analysis prioritized TG (MIP: 0.336; θ^MACE: -0.025; PP: 0.31; θ^λ: -0.072) and HDL-C (MIP: 0.254; θ^MACE: -0.011; PP: 0.232; θ^λ: -0.04) for CD and TC (MIP: 0.721; θ^MACE: -0.257; PP: 0.648; θ^λ: -0.356) and LDL-C (MIP: 0.31; θ^MACE: -0.095; PP: 0.256; θ^λ: -0.344) for UC as the top-ranked protective factors. In conclusion, the causal effect of TC for UC prevention was robust across all of our MR approaches, which provide the first evidence that genetically determined TC is causally associated with reduced risk of UC. The finding of this study provides important insights into the metabolic regulation of IBDs and potential metabolites targeting strategies for IBDs intervention.

7.
Clin. transl. oncol. (Print) ; 25(4): 873-881, abr. 2023.
Artigo em Inglês | IBECS | ID: ibc-217748

RESUMO

Platelet-derived microvesicles (PMVs), the microvesicles with the highest concentration in the bloodstream, play a key role in the regulation of hemostasis, inflammation, and angiogenesis. PMVs have recently been identified as key factors in the link between platelets and cancer. PMVs bind to both cancer cells and nontransformed cells in the microenvironment of the tumor, and then transfer platelet-derived contents to the target cell. These contents have the potential to either stimulate or modulate the target cell's response. PMVs are encased in a lipid bilayer that contains surface proteins and lipids as well as components found inside the PMV. Each of these components participates in known and potential PMV roles in cancer. The complicated roles played by PMVs in the onset, development, and progression of cancer and cancer-related comorbidities are summarized in this study (AU)


Assuntos
Humanos , Micropartículas Derivadas de Células/metabolismo , Neoplasias/metabolismo , Neoplasias/terapia , Microambiente Tumoral
8.
Clin Transl Oncol ; 25(4): 873-881, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36417084

RESUMO

Platelet-derived microvesicles (PMVs), the microvesicles with the highest concentration in the bloodstream, play a key role in the regulation of hemostasis, inflammation, and angiogenesis. PMVs have recently been identified as key factors in the link between platelets and cancer. PMVs bind to both cancer cells and nontransformed cells in the microenvironment of the tumor, and then transfer platelet-derived contents to the target cell. These contents have the potential to either stimulate or modulate the target cell's response. PMVs are encased in a lipid bilayer that contains surface proteins and lipids as well as components found inside the PMV. Each of these components participates in known and potential PMV roles in cancer. The complicated roles played by PMVs in the onset, development, and progression of cancer and cancer-related comorbidities are summarized in this study.


Assuntos
Micropartículas Derivadas de Células , Neoplasias , Humanos , Plaquetas , Micropartículas Derivadas de Células/metabolismo , Neoplasias/metabolismo , Microambiente Tumoral
9.
Am J Cancer Res ; 13(12): 6113-6124, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38187070

RESUMO

Recent studies have indicated that platelets may play a role in the advancement of pancreatic cancer by supporting tumor growth and increasing resistance to chemotherapy. This study aims to develop a prognostic model for pancreatic cancer using a platelet-related gene risk score. Prognostic platelet-related genes (PRGs) were identified from public databases and analyzed using cluster analysis. We investigated the microenvironment signatures and gene mutation patterns across different PRG-based molecular subtypes of pancreatic cancer. A prognostic model based on PRGs was developed using LASSO-Cox Regression Analysis. Additionally, we examined the correlation between the risk score and tumor clinical characteristics, as well as drug sensitivity. Two molecular subtypes, cluster C1 and C2, were identified. Cluster C2 was associated with a poorer prognosis compared to Cluster C1. The C1 group exhibited higher scores for activated CD8+ T cells, central memory CD4+ T cells, and natural killer T cells. The C2 group demonstrated a higher frequency of gene mutations. We established and validated a novel prognostic prediction model and platelet-related gene risk score for pancreatic cancer. The risk score was positively correlated with T stage, N stage, and tumor grade, and it presented a significant prognostic value compared to other clinical factors. In conclusion, a novel prognostic prediction model focusing on platelet involvement in pancreatic cancer has been developed, offering potential benefits for future drug therapies and clinical prognostic assessments.

10.
ACS Omega ; 6(25): 16565-16572, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34235328

RESUMO

Manganese dioxide (MnO2) nanosheet-based fluorescence sensors often use oxidase-like activity or wide absorption spectrum for detection of antioxidants. In those strategies, MnO2 nanosheets were reduced to Mn2+ by antioxidants. However, few strategies emphasize the role of Mn2+ obtained from MnO2 reduction in the design of the fluorescence sensor. Herein, we expanded the application of a MnO2 nanosheet-based fluorescence sensor by involving Mn2+ in the detection process using ascorbic acid (AA) as a model target. In this strategy, carbon dots (CDs), MnO2 nanosheets, and tetraphenylporphyrin tetrasulfonic acid (TPPS) comprise a ternary system for ratiometric fluorescence detection of AA. Initially, CDs were quenched by MnO2 nanosheets based on the inner filter effect, while TPPS maintained its fluorescence intensity. After the addition of AA, MnO2 nanosheets were reduced to Mn2+ so that the fluorescence intensity of CDs was recovered and TTPS was quenched by coordination with Mn2+. Overall, AA triggered an emission intensity increase at 440 nm for CDs and a decrease at 640 nm for TPPS. The ratio intensity of CDs to TPPS (F 440/F 640) showed a good linear relationship from 0.5 to 40 µM, with a low detection limit of 0.13 µM for AA detection. By means of the alkaline phosphatase (ALP)-triggered generation of AA, this strategy can be applied for the detection of ALP in the range of 0.1-100 mU/mL, with a detection limit of 0.04 mU/mL. Furthermore, this sensor was applied to detect AA and ALP in real, complex samples with ideal recovery. This novel platform extended the application of MnO2 nanosheet-based fluorescence sensors.

12.
Cell Death Dis ; 12(3): 265, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33712558

RESUMO

NOXA, a BH3-only proapoptotic protein involved in regulating cell death decisions, is highly expressed but short-lived in colorectal cancer (CRC). Neddylated cullin-5 (CUL5)-mediated ubiquitination and degradation of NOXA is crucial to prevent its overaccumulation and maintain an appropriate action time. However, how this process is manipulated by CRC cells commonly exposed to oxidative stress remain unknown. The peroxiredoxin PRDX1, a conceivable antioxidant overexpressed in CRC tissues, has been shown to inhibit apoptosis and TRAF6 ubiquitin-ligase activity. In this study, we found that PRDX1 inhibits CRC cell apoptosis by downregulating NOXA. Mechanistically, PRDX1 promotes NOXA ubiquitination and degradation, which completely depend on CUL5 neddylation. Further studies have demonstrated that PRDX1 oligomers bind with both the Nedd8-conjugating enzyme UBE2F and CUL5 and that this tricomplex is critical for CUL5 neddylation, since silencing PRDX1 or inhibiting PRDX1 oligomerization greatly dampens CUL5 neddylation and NOXA degradation. An increase in reactive oxygen species (ROS) is not only a hallmark of cancer cells but also the leading driving force for PRDX1 oligomerization. As shown in our study, although ROS play a role in upregulating NOXA mRNA transcription, ROS scavenging in CRC cells by N-acetyl-L-cysteine (NAC) can significantly reduce CUL5 neddylation and extend the NOXA protein half-life. Therefore, in CRC, PRDX1 plays a key role in maintaining intracellular homeostasis under conditions of high metabolic activity by reinforcing UBE2F-CUL5-mediated degradation of NOXA, which is also evidenced in the resistance of CRC cells to etoposide treatment. Based on these findings, targeting PRDX1 could be an effective strategy to overcome the resistance of CRC to DNA damage-inducing chemotherapeutics.


Assuntos
Neoplasias Colorretais/enzimologia , Proteínas Culina/metabolismo , Peroxirredoxinas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Apoptose , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Proteínas Culina/genética , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Células HEK293 , Células HT29 , Meia-Vida , Humanos , Peroxirredoxinas/genética , Multimerização Proteica , Proteólise , Proteínas Proto-Oncogênicas c-bcl-2/genética , Espécies Reativas de Oxigênio/metabolismo , Enzimas de Conjugação de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitinação
13.
Cancer Lett ; 492: 185-196, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32758616

RESUMO

Breast cancer is the most common cancer among women worldwide, with 70% being estrogen receptor-positive (ER+). Although ER-targeted treatment is effective in treating ER + breast cancer, chemoresistance and metastasis still prevail. Outcome-predictable biomarkers can help improve patient prognosis. Through the analysis of the Array Express database, The Cancer Genome Atlas-Breast Cancer datasets, and breast tumor tissue array results, we found that cytochrome c oxidase subunit 5a (COX5A) was related to poor prognosis of ER + breast cancer. Further studies revealed that COX5A was positively associated with metastasis and chemoresistance in ER + breast cancer. In vitro experiments showed that knockdown of COX5A was accompanied by a decrease in ERα expression, cell cycle arrest, and epithelial-mesenchymal transition blockade, resulting in an inhibition of proliferation and invasion. Knockdown of COX5A enhanced the chemosensitivity of breast cancer cells by decreasing adenosine triphosphate and increasing reactive oxygen species levels. We report that miR-204 can target and inhibit the expression of COX5A, thus, reversing the functions of COX5A in ER + breast cancer cells. We found that COX5A may serve as a prognostic biomarker in ER + breast cancer.


Assuntos
Neoplasias da Mama/patologia , Complexo IV da Cadeia de Transporte de Elétrons/fisiologia , MicroRNAs/fisiologia , Receptores de Estrogênio/análise , Adulto , Idoso , Neoplasias da Mama/química , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Complexo IV da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Complexo IV da Cadeia de Transporte de Elétrons/genética , Transição Epitelial-Mesenquimal , Feminino , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica
14.
Analyst ; 145(7): 2661-2668, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32104830

RESUMO

A simple core shell structured fluorescent sensor was constructed to realize simultaneous detection of hexavalent and trivalent chromium ions. Briefly, blue-carbon dots (b-CDs) were embedded into a silica sphere, then a Cr(iii) imprinted silica layer doped with red-CDs (r-CDs) was coated onto the b-CDs@SiO2. Cr(vi) can selectively quench b-CDs based on the inner filter effect and Cr(iii) can selectively quench r-CDs based on electron transfer with the aid of the ion imprinting technique. In this strategy, it was not necessary to reduce Cr(vi) to Cr(iii) or oxidize Cr(iii) to Cr(vi), the chromium speciation of both can be detected simultaneously. When Cr(vi) was detected in the blue channel, the fluorescence intensity quenching effect was seen at 440 nm, and was linear from 0.01 to 10.0 µM, with a detection limit of 3.8 nM. For the detection of Cr(iii) in the red channel, the fluorescence intensity quenching effect was seen at 605 nm, and was linear from 0.1 to 15.0 µM, with a detection limit of 46 nM. This strategy enjoyed the advantages of simple construction, convenient detection, good selectivity and high sensitivity.

15.
ACS Appl Bio Mater ; 3(4): 2455-2465, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35025295

RESUMO

The fabrication of polymer micelles, both with ample intracorporeal circulation stability and fast release within cancerous cells, is still facing challenges. Herein, we fabricated a strategy to improve the stability of polymer micelles using pseudo- and chemical crosslinking jointly. To be specific, a star-shaped polymer (TMP-PGMA-g-PEG) with trimethylolpropane (TMP) as the inner core was synthesized with glycidyl methacrylate (GMA), followed by the graft reaction with amine-terminated poly(ethylene glycol) (mPEG-NH2). Star polymer micelle-based nanomedicines (TPP/paclitaxel (PTX)) were obtained using paclitaxel (PTX) as a model drug and polymer micelles (TPP) as carriers, which were constructed by TMP-PGMA-g-PEG. The star core and arms behaved as pseudo crosslinkers, which reduced their critical micelle concentration (CMC) values and improved their stability; profoundly, cystamine was used as a chemical crosslinker to react with the rest of the epoxy groups of TPP or TPP/PTX and further improve their stability. Finally, dual pseudo and chemical crosslinked star polymer micelles (CTPP) and micelle-based nanomedicines (CTPP/PTX) were obtained. The results demonstrated that CTPP/PTX with combined stability design presented excellent stability both in vitro and in vivo physiological conditions. Notably, cystamine not only served as a crosslinker but also had a reduction-responsive disulfide bond to achieve fast release inside cancer cells with a high level of glutathione (GSH). This smart design effectively resolved the antinomy that the polymer micelle delivery system could not cause rapid release in tumor sites when it possesses extreme stability resulted from chemical crosslinking. Both in vitro and in vivo experiments clearly stated the advantages of CTPP/PTX, including excellent stability, fast reduction-responsive release, and remarkable antitumor efficacy.

16.
ACS Omega ; 4(25): 21500-21508, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31867546

RESUMO

A method for green synthesis of sulfur, nitrogen co-doped photoluminescence carbon dots (S,N/CDs) originating from two natural biomass was proposed. By simple hydrothermal heating of bean pod and onion, blue emission CDs were prepared. Ag+ can effectively quench the as-prepared S,N/CDs. Under optimized conditions, the linear range of the established method for Ag+ detection was 0.1-25 µM, and the detection of limit based on 3S/N was 37 nM. More interestingly, the addition of Ag+ can induce an evident color change of S,N/CDs from yellow to brown under sunlight. The developed method was applied for detection of Ag+ in river water and tap water samples. Satisfied recoveries ranging from 96.0 to 102.0% with precision below 4.1% were obtained. S,N/CDs showed low toxicity toward 4T1 cells, which also can be extended to cellular imaging and intracellular Ag+ detection. The simple and green approach proposed here could meet the requirements for bioimaging and environmental monitoring.

17.
Analyst ; 144(21): 6283-6290, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31588432

RESUMO

When molecularly imprinted fluorescent polymers (MIFPs) are prepared by the doping method (d-MIFPs), the fluorescent nanoparticles are quenched and passivated during the polymerization and elution process, and their detection sensitivity would be reduced. In this study, to overcome this drawback, MIFPs were synthesized by post-imprinting modification based on multilevel mesoporous structured silica. Briefly, multilevel mesoporous-structured BPA-imprinted polymers (MIPs) were prepared at first, and then, CdTe quantum dots were anchored onto the large pores of the MIPs to form p-MIFPs. Due to the well-maintained fluorescence intensity and low background, the sensitivity of the p-MIFPs was two orders of magnitude higher than that of the d-MIFPs. The F0/F- 1 of p-MIFPs was linear with BPA in the range of 0.005 to 4.0 µM with an LOD of 0.57 nM. Furthermore, post-imprinting modification was adopted to achieve ratiometric fluorescent MIPs (p-r-MIFPs) by simultaneously anchoring carbon dots and quantum dots onto the MIPs. The p-MIFPs and p-r-MIFPs were successfully applied to determine BPA in water samples with average recoveries ranging from 96.4% to 102.0% and an RSD below 4.1%. The results prove that post-imprinting modification is an effective method to construct MIFPs with conspicuous sensitivity, and multilevel mesoporous silica is an ideal matrix for the post-imprinting modification.

18.
ACS Sens ; 4(7): 1917-1924, 2019 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-31273977

RESUMO

Blue and red dual channel dual emission carbon dots (DDCDs) were synthesized by a one-step hydrothermal method in water-formamide binary system using citric acid and ethylenediamine as precursors. Then, the as-prepared DDCDs were directly employed for preparation of ion imprinted fluorescence polymers without further separation. Since Cr3+ can only quench the fluorescence of blue CDs, while Pb2+ only quenches the fluorescence of red CDs, dual channel detection of Cr3+ and Pb2+ can be achieved simultaneously based on ion imprinted fluorescence polymers. Under optimized conditions, the quenching effect [(F0 - F)/F0] at 440 nm for the blue channel against the concentration of Cr3+ was linear from 0.1 to 6.0 µM, while that for the red channel at 580 nm against the concentration of Pb2+ was linear from 0.1 to 5.0 µM. The detection limits for Cr3+ and Pb2+ can reach 27 nM and 34 nM, respectively. Satisfied recoveries have also been obtained for detection of Cr3+ and Pb2+ in real water samples. The application of this dual channel detection method will greatly simplify the heavy metal ion detection process in complicated water environments.


Assuntos
Carbono/química , Cromo/análise , Corantes Fluorescentes/química , Chumbo/análise , Polímeros/química , Pontos Quânticos/química , Cromo/química , Cor , Fluorescência , Lagos/análise , Chumbo/química , Limite de Detecção , Rios/química , Espectrometria de Fluorescência/métodos , Poluentes Químicos da Água/análise
19.
ACS Appl Mater Interfaces ; 11(23): 20649-20659, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31117440

RESUMO

A polymer micelle-based drug delivery system has faced many challenges due to the lack of stability especially after being diluted in blood, resulting in a premature release. Herein, we developed camptothecin (CPT)-conjugated prodrug (CPTP) micelles in which CPT was grafted to the poly(ethylene glycol)-poly(glutamic acid) block copolymer via a disulfide bond linker for a redox-triggered drug release. Then, the cisplatin (CDDP)-crosslinked CPT-prodrug micelles (CPTP/CDDP) with a hybrid complex as a stable structure were successfully established via the CDDP (Pt)-carboxyl (COOH) chelate interaction. The resulting dual CPTP/CDDP had an average hydrodynamic radius of about 50 nm with a narrow distribution, which was conducive to the promotion of solid tumor accumulation. Importantly, CPT chemical bonding to the polymer backbone obviously stabilizes the CPT-prodrug micelles and prolongs their circulation time. Moreover, both CPT and CDDP are clinically used antitumor drugs; CDDP not only behaves as an ancillary anticarcinogen but also serves as a crosslinker to restrain the untimely burst release of CPT and to achieve synergistic antitumor efficacy. In addition, the CPTP/CDDP also exhibited a sustained reduction responsive release of CPT accompanied by the dissociation of the CDDP-COOH complex. This design ingeniously solved the contradiction between the stability and release of polymer micelle-based nanomedicines. Both in vitro and in vivo tests demonstrated an amazing antineoplastic efficacy compared with free drugs (CPT or CDDP) and just their physical mixing, indicating great promise for cancer treatment.


Assuntos
Antineoplásicos/química , Camptotecina/química , Cisplatino/química , Nanomedicina/métodos , Pró-Fármacos/química , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Camptotecina/administração & dosagem , Camptotecina/uso terapêutico , Linhagem Celular Tumoral , Cisplatino/administração & dosagem , Cisplatino/uso terapêutico , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Feminino , Espectroscopia de Ressonância Magnética , Camundongos , Camundongos Endogâmicos BALB C , Micelas , Polietilenoglicóis/química , Ácido Poliglutâmico/química
20.
Anal Chim Acta ; 1048: 178-185, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30598148

RESUMO

A simple and sensitive inner filter effect and charge transfer dual response ratiometric fluorescent probe (D-RFP) for sensing glucose was developed based on etching of silver nanoprisms (Ag NPRs). The D-RFP was proposed by hybridizing red emitting CdTe QDs and blue emitting CDs into core-shell structured silica nanoparticles. In this design, when mixed Ag NPRs with the D-RFP, QDs which embedded in silica nanoparticles can be quenched by Ag NPRs via inner filter effect. Ag NPRs can be effectively etched to silver ions by H2O2 which can bind with CDs and quench CDs by charge transfer. The etching of Ag NPRs leaded to the recovering the fluorescence of QDs and quenching the fluorescence of CDs. Under optimal condition, D-RFP can be exploited for H2O2 detection with detection limit of 0.28 µM and glucose sensing with detection limit of 0.64 µM. The developed approach was applied to monitor glucose levels in human serum samples with satisfactory results. Moreover, this method provided a new idea for designing D-RFP and can be extended to other detection systems based on silver nanoparticles (including Ag NPs, Ag NPRs, or Au@Ag nanorods) etching process.


Assuntos
Colorimetria/métodos , Corantes Fluorescentes/química , Glucose/análise , Peróxido de Hidrogênio/sangue , Pontos Quânticos/química , Prata/química , Compostos de Cádmio/química , Carbono/química , Cor , Diabetes Mellitus/sangue , Fluorescência , Corantes Fluorescentes/síntese química , Glucose Oxidase/química , Humanos , Peróxido de Hidrogênio/química , Limite de Detecção , Oxirredução , Dióxido de Silício/química , Telúrio/química
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