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Owing to the adverse effects of oxytetracycline (OTC) residues on human health, it is of great importance to construct a rapid and effective strategy for OTC detection. Herein, we developed a dual-response fluorescence sensing platform based on molybdenum sulfide quantum dots (MoS2 QDs) and europium ions (Eu3+) for ratiometric detection of OTC. The MoS2 QDs, synthesized through an uncomplicated one-step hydrothermal approach, upon OTC integration into the MoS2 QDs/Eu3+ sensing system, exhibit a significant quenching of blue fluorescence due to the inner filter effect (IFE), simultaneously enhancing the distinct red emission of Eu3+ at 624 nm, a phenomenon attributed to the antenna effect (AE). This sensor demonstrates exceptional selectivity and sensitivity towards OTC, characterized by a linear detection range of 0.2-10 µM and a notably low detection limit of 2.21 nM. Furthermore, we achieved a visual semi-quantitative assessment of OTC through the discernible fluorescence color transition from blue to red under a 365 nm ultraviolet lamp. The practical applicability of this sensor was validated through the successful detection of OTC in milk and mutton samples, underscoring its potential as a robust tool for OTC monitoring in foodstuffs to safeguard food safety.
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Európio , Corantes Fluorescentes , Leite , Molibdênio , Oxitetraciclina , Pontos Quânticos , Espectrometria de Fluorescência , Oxitetraciclina/análise , Leite/química , Pontos Quânticos/química , Molibdênio/química , Animais , Európio/química , Espectrometria de Fluorescência/métodos , Corantes Fluorescentes/química , Dissulfetos/química , Contaminação de Alimentos/análise , Limite de Detecção , FluorescênciaRESUMO
Colorectal cancer (CRC) has a high degree of heterogeneity and identifying the genetic information of individual tumor cells could help enhance our understanding of tumor biology and uncover potential therapeutic targets for CRC. In this study, we identified LPCAT2+ tumor cell populations with less malignancy than LPCAT2- tumor cells in human and mouse CRC tissues using scRNA-seq. Combining in vitro and in vivo experiments, we found that LPCAT2 could inhibit the proliferation of CRC cells by inducing ferroptosis. Mechanistically, LPCAT2 arrested PRMT1 in cytoplasm of CRC cells via regulating acetylation of PRMT1 at the K145 site. In turn, PRMT1 enhanced SLC7A11 promoter activity. Thus, LPCAT2 attenuated the positive regulatory effect of PRMT1 on SLC7A11 promoter. Notably, SLC7A11 acts as a ferroptosis regulator. Furthermore, in LPCAT2 knockout mice (LPCAT2-/-) colon cancer model, we found that LPCAT2-/- mice exhibited more severe lesions, while PRMT1 or SLC7A11 inhibitors delayed the progression. Altogether, we elucidated that LPCAT2 suppresses SLC7A11 expression by inhibiting PRMT1 nuclear translocation, thereby inducing ferroptosis in CRC cells. Moreover, inhibitors of the PRMT1/SLC7A11 axis could delay tumor progression in CRC with low LPCAT2 expression, making it a potentially effective treatment for CRC.
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Sistema y+ de Transporte de Aminoácidos , Neoplasias Colorretais , Progressão da Doença , Proteína-Arginina N-Metiltransferases , Animais , Humanos , Camundongos , Sistema y+ de Transporte de Aminoácidos/genética , Sistema y+ de Transporte de Aminoácidos/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Ferroptose/genética , Ferroptose/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Camundongos Knockout , Proteína-Arginina N-Metiltransferases/metabolismo , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/antagonistas & inibidores , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismoRESUMO
Traditional molecular imaging tools used for detecting liver diseases own several drawbacks, such as poor optical performance and limited applicability. Monitoring the concentration of leucine aminopeptidase (LAP), which is closely related to liver diseases such as liver cancer and liver injury, and analyzing it in diagnosis, drug evaluation, and surgical treatment is still a challenging task. Herein, we construct an intramolecular charge-transfer mechanism-based, ultrasensitive, near-infrared fluorescent probe (LAN-lap) for dynamic monitoring of LAP fluctuations in living systems. LAN-lap, with high specificity, stability, sensitivity, and water solubility, can achieve in vitro monitoring of LAP through both fluorescence and colorimetric methods. Moreover, LAN-lap can successfully be used for the localization imaging of endogenous LAP, confirming the upregulation of LAP expression in liver cancer and liver injury cells. In addition, LAN-lap can realize the imaging of liver tumors in living organisms. Meanwhile, it can intuitively present the degree of drug-induced liver injury, achieving semi-quantitative imaging evaluation of the hepatotoxicity of two drugs. Furthermore, LAN-lap can track liver cancer tumors in mice with peritoneal metastasis and can assist in fluorescence-guided surgical resection of liver cancer tumors. This multifunctional LAN-lap probe could play an important role in facilitating simultaneous diagnoses, imaging, and synergistic surgical navigation to achieve better point-of-care therapeutic efficacy.
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Doença Hepática Induzida por Substâncias e Drogas , Neoplasias Hepáticas , Animais , Camundongos , Leucil Aminopeptidase/metabolismo , Avaliação de Medicamentos , Corantes Fluorescentes , Neoplasias Hepáticas/diagnóstico por imagem , Imagem MolecularRESUMO
Introduction: Carboxylesterases (CXEs) and glutathione S-transferases (GSTs) can terminate olfactory signals during chemosensation by rapid degradation of odorants in the vicinity of receptors. The tea grey geometrid, Ectropis grisescens (Lepidoptera, Geometridae), one of the most devastating insect herbivores of tea plants in China, relies heavily on plant volatiles to locate the host plants as well as the oviposition sites. However, CXEs and GSTs involved in signal termination and odorant clearance in E. grisescens remains unknown. Methods: In this study, identification and spatial expression profiles of CXEs and GSTs in this major tea pest were investigated by transcriptomics and qRT-PCR, respectively. Results: As a result, we identified 28 CXEs and 16 GSTs from female and male antennal transcriptomes. Phylogenetic analyses clustered these candidates into several clades, among which antennal CXEs, mitochondrial and cytosolic CXEs, and delta group GSTs contained genes commonly associated with odorants degradation. Spatial expression profiles showed that most CXEs (26) were expressed in antennae. In comparison, putative GSTs exhibited a diverse expression pattern across different tissues, with one GST expressed specifically in the male antennae. Disscussion: These combined results suggest that 12 CXEs (EgriCXE1, 2, 4, 6, 8, 18, 20-22, 24, 26, and 29) and 5 GSTs (EgriGST1 and EgriGST delta group) provide a major source of candidate genes for odorants degradation in E. grisescens.
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Molecular mechanisms underlying wing evolution and development have been a point of scientific inquiry for decades. Phloem-feeding aphids are one of the most devastating global insect pests, where dispersal of winged morphs lead to annual movements, migrations, and range expansions. Aphids show a polyphenic wing dimorphism trait, and offer a model to study the role of environment in determining morphological plasticity of a single genotype. Despite recent progresses in the genetic understanding of wing polyphenism, the influence of environmental cues remains unclear. To investigate the involvement of miRNAs in wing development, we sequenced small RNA libraries of the English grain aphid, Sitobion avenae (F.) across six different developmental stages. As a result, we identified 113 conserved and 193 S. avenae-specific miRNAs. Gene Ontology and KEGG pathway analyses of putative target mRNAs for the six differentially expressed miRNAs are enriched for wing development processes. Dietary uptake of miR-263a, miR-316, and miR-184a agomirs and antagomirs led to significantly higher mortality (>70%) and a lower proportion of winged morphs (<5%). On the other hand, wing malformation was observed in miR-2 and miR-306 agomirs and miR-2 and miR-14 antagomirs, respectively, suggesting their involvement in S. avenae wing morphogenesis. These combined results not only shed light on the regulatory role of miRNAs in wing dimorphism, but also provide potential novel targets for the long-term sustainable management of S. avenae, a devastating global grain pest.
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Afídeos , MicroRNAs , Animais , Antagomirs/metabolismo , Afídeos/genética , Afídeos/metabolismo , Genótipo , MicroRNAs/genética , MicroRNAs/metabolismo , Asas de AnimaisRESUMO
The efficiency of photodynamic therapy (PDT) is severely constrained due to the innate hypoxic environment, besides the elevated level of glutathione (GSH). To get rid of the hypoxic environment and higher concentrations of GSH in the solid tumors, we propose an approach of oxygen self-sufficient multimodal imaging-guided nanocomposite CaO2-MnO2-UCNPs-Ce6/DOX (abbreviated as CaMn-NUC), in which CaO2 nanoparticles in the hydrophobic layer were seated on the hydrophilic MnO2 sheet and conjugated with chlorin e6 (Ce6) loaded upconversion nanoparticles (UCNPs-Ce6) via the click chemistry approach. CaMn-NUC was presented to overcome hypoxia and GSH-associated photodynamic resistance due to in situ oxygen generation and GSH reduction of MnO2 upon endocytosis, and a bulk amount of Mn2+ ions generated in the process under acidic tumor environment acts as the MRI contrast agent. Moreover, the MnO2 sheet protects Ce6 from self-degradation under irradiation; thus, it can be used to switch control of cellular imaging. Afterwards, in a regulated and targeted manner, the chemotherapeutic drug (doxorubicin hydrochloride, DOX) can be released with the degradation of CaMn-NUC in the acidic tumor microenvironment (TME). Thus, we testify a competent nanoplatform employing 808 nm-excited UCNPs-Ce6 for concurrent imaging and PDT in consideration of the large anti-Stokes shifts, deep penetration into biological tissues, narrow emission bands, and high spatial-temporal resolution of the UCNPs. Thus, our proposed nanoplatform postulates a strategy to efficiently kill cancer cells in a concentration- and time-dependent manner via the in situ oxygenation of solid tumor hypoxia to enhance the efficiency of multimodal imaging-guided chemo-photodynamic therapy.
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Mitocôndrias/metabolismo , Imagem Multimodal/métodos , Nanocompostos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Animais , Feminino , Células HeLa , Humanos , Camundongos , Mitocôndrias/efeitos dos fármacos , Nanocompostos/administração & dosagem , Oxigênio/metabolismo , Fármacos Fotossensibilizantes/administração & dosagem , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/fisiologia , Microambiente Tumoral/fisiologiaRESUMO
Gasotransmitters with high therapeutic efficacy and biosafety have been drawing the attention of researchers. Nevertheless, how to effectively deliver gases to and precisely control their generation at the lesion as well as integrate them with other therapies to realize precision therapy have remained elusive. Herein, we report a versatile Cu2+-initiated nitric oxide (NO) nanocomposite for multimodal imaging-guided synergistic chemodynamic/photodynamic/gas therapy. After the nanomedicine was ingested by tumor cells, the acidic tumor microenvironment accelerated the decomposition of CuO2 and simultaneously triggered the Fenton-like catalytic reaction of Cu2+ and H2O2 to produce highly toxic ËOH. By virtue of the NO generation and glutathione depletion, UMNOCC-PEG can relieve the antioxidant capacity and hypoxia of the tumor to improve the efficiency of chemodynamic therapy (CDT) and photodynamic therapy (PDT). Importantly, NO and reactive oxygen species (ROS) can generate reactive nitrogen species (RNS), which can result in DNA damage, further improving the therapeutic effect (cell apoptosis rate up to 93.4%). Moreover, the inherent properties of lanthanide ions endow UMNOCC-PEG with upconversion luminescence (UCL), CT and MRI trimodal imaging capability, achieving precise cancer treatment. By taking advantage of these features, the strategy developed here may provide a promising application foreground to conquer malignant tumors.
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Nanocompostos , Fotoquimioterapia , Gases , Peróxido de Hidrogênio , Medicina de Precisão , Dióxido de Silício , Nanomedicina TeranósticaRESUMO
Multimodal synergistic therapy based on photodynamic therapy (PDT), photothermal therapy (PTT), and chemodynamic therapy (CDT) has attracted increasing attention in cancer therapy. However, the scant therapeutic efficiency is always a barrier for further application. Herein, a smart tumor microenvironment (TME) responsive nanocatalysts are developed by adopting Fe-Mn layered double hydroxides (FeMn-LDH) as an effective photothermal nanocarrier to load mesoporous silica and chlorin e6 (Ce6)-covalently coated upconversion nanoparticles (UCSP) for multimodal imaging for directed therapy. Under acidic TME, FeMn-LDH degrades into Fe3+ and Mn2+ ions to initiate a Fenton-like reaction inducing CDT and enhancing magnetic resonance imaging. Additionally, Fe3+ can decompose H2 O2 to oxygen (O2 ), enhancing PDT guided by UCSP. As a representative noninvasive imaging probe, the upconversion luminescence will recover after decomposition of FeMn-LDH, and provide high-resolution upconversion luminescent imaging guidance for pinpointed PDT. Moreover, the photothermal properties of FeMn-LDH can further enhance CDT effects. The synergistic therapy and multifunctional imaging can realize the integration of diagnosis and treatment.
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Nanopartículas , Fotoquimioterapia , Hidróxidos , Oxigênio , Fármacos Fotossensibilizantes/uso terapêuticoRESUMO
Photodynamic therapy (PDT) and photothermal therapy (PTT) are well-developed light therapy methods for cancer; however, both have a few areas that need improvement. A sustained PDT effect depends on the sustained generation of reactive oxygen species (ROS); therefore, adjusting the type of photosensitizer or the reaction mechanism to prolong the duration of the oxidation-reduction reaction is a possible solution for the continuation of the PDT effect. Further, if PTT could be combined with other treatments, it would bring about a more satisfactory therapeutic effect. To increase the treatment effect of the above two therapeutic methods, a collaborative treatment model of photo/chemodynamic therapy (PCDT) and PTT is needed and is the focus of this study. On the one hand, PCDT is a therapy that integrates PDT with Fenton-like reactions, and Fenton-like reactions can help PDT to produce more ROS by making better use of H2O2 in the tumor microenvironment. On the other hand, the PTT effect can also promote PCDT effects to some extent because rising temperature can elevate the redox reaction rate. Therefore, a copper oxide semiconductor photosensitizer was selected in this research to realize the abovementioned therapeutic purposes and experimental concepts. A porous silica carrier can facilitate the uniform attachment of the copper oxide photosensitizer to the SiO2 surface to form a relatively uniform nanostructure, and the nanoporous structure can increase the performance of the whole material to a certain extent. Based on these perspectives, SiO2@CuO nanotube (NT), an agent of both Fenton-like photosensitization and photothermal reagent, is synthesized by the hydrothermal co-precipitation template approach to shrink the tumor through the combined effect of PCDT and PTT. In this system, copper ions can participate in the Fenton-like reactions and make better use of H2O2 to generate more ROS. Herein, 808 nm light was chosen for irradiation because of its suitable excitation ability, applicable penetration and low intrinsic damage. The experimental results show that SiO2@CuO NT is a promising agent that combines PCDT and PTT for cancer treatment. This work provides guidance for the synthesis of Fenton-like photosensitizers for the PCDT effect.
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Nanotubos de Carbono/química , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Terapia Fototérmica/métodos , Dióxido de Silício/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Terapia Combinada/métodos , Relação Dose-Resposta a Droga , Feminino , Células HeLa , Humanos , Raios Infravermelhos , Camundongos , Fármacos Fotossensibilizantes/administração & dosagem , Porosidade , Dióxido de Silício/administração & dosagem , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/fisiologiaRESUMO
Hypoxia in tumor cells is regarded as the most crucial cause of clinical drug resistance and radio-resistance; thus, relieving hypoxia of tumor cells is the key to enhancing the efficacy of anticancer therapy. As a gas signal molecule of vasodilatation factors, nitric oxide (NO) can relieve the hypoxia status of tumor cells, thereby, enhancing the sensitivity of tumor cells to radiotherapy. However, considering complications of vascular activity, the level of NO required for radiotherapy sensitization cannot be obtained in vivo. In view of this, we design and fabricate a multifunctional bismuth-based nanotheranostic agent, which is functionalized with S-nitrosothiol and termed Bi-SNO NPs. X-rays break down the S-N bond and simultaneously trigger large amount of NO-releasing (over 60 µM). Moreover, the as-prepared Bi-SNO NPs not only possess the capability of absorbing and converting 808 nm NIR photons into heat for photothermal therapy, but also have the ability to increase X-ray absorption and CT imaging sensitivity. In addition, the collaborative radio-, photothermal-, and gas-therapy of Bi-SNO in vivo was further investigated and remarkable synergistic tumor inhibition was realized. Finally, no obvious toxicity of Bi-SNO NPs was observed in the treated mice within 14 days. Therefore, the Bi-SNO developed in this work is an effective nano-agent for cancer theranostics with well-controlled morphology and uniform size (36 nm), which could serve as a versatile CT imaging-guided combined radio-, photothermal- and gas-therapy nanocomposite with negligible side effects.
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Nanopartículas , Nanomedicina Teranóstica , Animais , Bismuto , Camundongos , Óxido Nítrico , Fototerapia , Raios XRESUMO
Photodynamic therapy (PDT) is a light-based modality for tumor treatment that involves the generation of reactive oxygen species (ROS) by the combination of light, a photosensitizer, and molecular oxygen. Nevertheless, the therapeutic effects of PDT are limited by hypoxic conditions that worsen with oxygen consumption during the PDT process. Photo/chemodynamic therapy (PCDT) based on the Fenton reaction is one strategy to improve ROS generation, provided a highly effective Fenton reagent is developed. In this research, SiO2@Cu7S4 nanotubes (NTs) were synthesized as a PCDT agent. This double-valence metal-sulfide composite material can react with H2O2 at the tumor site. SiO2@Cu7S4 NTs can produce more ROS than the traditional PDT agents, and besides, they can also be used as a photothermal therapy (PTT) agent. SiO2@Cu7S4 NTs will trigger the PTT effect under 808 nm irradiation and generate a large amount of heat to eradicate cancer cells. This heat will also promote the PCDT effect by increasing the reaction rate. Thus, the SiO2@Cu7S4 NT is a suitable material for PCDT and PTT synergistic oncotherapy. The 808 nm laser is selected as the appropriate excitation source, providing adequate penetration and minimal harm to normal cells. The experimental data presented herein demonstrate the promising photosensitive, Fenton-like, and photothermal performance of SiO2@Cu7S4 NTs. Furthermore, the findings could promote the development of PCDT and PTT synergistic therapy. Thus, this research provides a feasible method to design a single, multifunctional material for cancer treatment.
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Antineoplásicos/farmacologia , Cobre/farmacologia , Nanotubos/química , Fármacos Fotossensibilizantes/farmacologia , Fototerapia , Dióxido de Silício/farmacologia , Compostos de Enxofre/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cobre/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lasers , Camundongos , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Tamanho da Partícula , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Espécies Reativas de Oxigênio/metabolismo , Dióxido de Silício/química , Compostos de Enxofre/química , Propriedades de SuperfícieRESUMO
Insect Odorant-Binding Proteins (OBPs) play crucial roles in the discrimination, binding and transportation of odorants. Herein, the full-length cDNA sequence of Minus-C OBP1 (MaltOBP1) from the Japanese pine sawyer beetle, Monochamus alternatus, was cloned by 3' and 5' RACE-PCR and analyzed. The results showed that MaltOBP1 contains a 435 bp open reading frame (ORF) that encodes 144 amino acids, including a 21-amino acid signal peptide at the N-terminus. The matured MaltOBP1 protein possesses a predicted molecular weight of about 14 kDa and consists of six α-helices, creating an open binding pocket, and two disulfide bridges. Immunoblotting results showed that MaltOBP1 was most highly expressed in antennae in both sexes, followed by wings and legs. Fluorescence assays demonstrated that MaltOBP1 protein exhibited high binding affinity with (R)-(+)-α-pinene, (-)-ß-pinene, trans-caryophyllene, (R)-(+)-limonene and (-)-verbenone, which are the main volatile compounds of the pine tree. Our combined results suggest that MaltOBP1 plays a role in host seeking behavior in M. alternatus.
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Photodynamic therapy (PDT) is commonly employed in clinics to treat the cancer, but because of the hypoxic tumor microenvironment prevalent inside tumors, PDT therapeutic efficiency is not adequate hence limiting the effectiveness of PDT. Therefore, we designed a nanocomposite consisting of reduced nanographene oxide (rGO) modified with polyethylene glycol (PEG), manganese dioxide (MnO2), upconversion nanoparticles (UCNPs), and Chlorin e6 (Ce6) to spark oxygen production from H2O2 with the aim of relieving the tumor hypoxic microenvironments. For in vivo tumor PDT and photothermal therapy (PTT), UCNPs-Ce6-labeled rGO-MnO2-PEG nanocomposites were used as a therapeutic agent, augmenting the therapeutic efficiency of PDT via redox progression through the catalytic H2O2 decomposition pathway and further achieving excellent tumor inhibition. It is important to mention that degradation of MnO2 in an acidic cellular microenvironment leads to the creation of a massive volume of Mn2+ which was employed as a contrast mediator for magnetic resonance imaging (MRI). Our research postulates an approach to spark O2 formation through an internal stimulus to augment the efficiency of MRI- and computerized tomography (CT)-imaging-guided PDT and PTT.
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Antineoplásicos/uso terapêutico , Nanocompostos/uso terapêutico , Nanopartículas/uso terapêutico , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/uso terapêutico , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Clorofilídeos , Feminino , Fluoretos/química , Fluoretos/efeitos da radiação , Fluoretos/uso terapêutico , Gadolínio/química , Gadolínio/efeitos da radiação , Gadolínio/uso terapêutico , Grafite/química , Grafite/uso terapêutico , Humanos , Raios Infravermelhos , Compostos de Manganês/química , Compostos de Manganês/uso terapêutico , Camundongos , Nanocompostos/química , Nanopartículas/química , Óxidos/química , Óxidos/uso terapêutico , Oxigênio/metabolismo , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Polietilenoglicóis/química , Polietilenoglicóis/uso terapêutico , Porfirinas/química , Porfirinas/efeitos da radiação , Microambiente Tumoral/fisiologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
In the present study, a novel ratiometric fluorescence probe based on dual-emitting Mn-doped ZnS quantum dots (Mn:ZnS QDs) was established for detection of Pb2+ and methyl parathion (MP). The dual-emitting Mn:ZnS QDs was aqueous synthesised in one pot and played as a ratiometric fluorescence probe for the detection of Pb2+ with high sensitivity. The fluorescence intensity ratio (F450nm/F585nm) of the probe against the concentration of Pb2+ showed a good linear relationship from 10â¯nM to 60â¯nM with a detection limit of 0.5â¯nM. Furthermore, the Mn:ZnS QDs/Pb2+ system was established as a turn-on fluorescence sensing system to quantitative measure the MP concentration. The fluorescence intensity at 450â¯nm exhibited a good linear relationship in the MP concentration range from 0.19 to 0.95⯵M with a detection limit of about 0.02⯵M. It also had a satisfying performance in fruit and environmental water samples. Therefore, the prepared Mn:ZnS QDs-based sensor has been established as a ratiometric fluorescence probe and turn-on method for quantitative detection of lead ion and MP, respectively.
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Typically, sialic acids (SA) with a nine-carbon backbone are found at the glycan chain termini on the cell membranes, which play crucial roles in various physiological and pathological processes. The expression level of SA in the blood serum has been reported to correlate with various disease states among cancer. In this study, a novel approach for preparing fluorescent boronic-acid-modified carbon dots (C-dots) for the detection of SA was developed. The functionalized C-dots were synthesized by a facile, one-step hydrothermal method using 3-pyridineboronic acid as the sole carbon source. The added SA selectively recognized the C-dots, leading to the fluorescence quenching of the C-dots in a linear range of 80-4000⯵M with a detection limit of 54⯵M. The as-developed boronic-acid nanoprobe was successfully applied for the detection of SA in human serum samples with satisfactory results. In addition, this method afforded results within 4â¯min. Compared to other methods, this new proposed approach was simpler and exhibited excellent sensitivity and selectivity, demonstrating immense potential as an alternative for SA detection.
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A novel fluorescence detection method based on competitive immunoassay and magnetic bioseparation technique was developed and applied to the determination of pig immunoglobulin G (IgG) in serum samples. Core-shell structured Fe3O4@SiO2 nanoparticles were synthesized by chemical coprecipitation, followed by functionalization with amino groups and immobilization of pig IgG antibodies. The synthesized Fe3O4@SiO2-antibody nanoparticles were employed as the probe for the competitive immune recognition of the target antigens in samples and the antigens labeled with fluorescein isothiocyanate (FITC). After the magnetic separation of probes binding with these two types of antigens, fluorescence of the free FITC-labeled antigens was measured for the quantification of the target antigens, since the ratio of the FITC-labeled antigens in supernatant before and after the competitive immune recognition depends on the amount of the target antigens in sample, due to the competitive nature of the binding of the antibody for these two types of antigens. Under the optimal conditions, a linear relationship was obtained between the change of fluorescence intensity and the concentration of pig IgG in a range from 0.75 to 23.50⯵gâ¯L-1, with a detection limit (LOD) of 0.031⯵gâ¯L-1. With the facile-prepared probes, this fluorescence competitive method can provide a rapid, specific and highly sensitive immunoassay protocol for the determination of target proteins in complex matrix samples.
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Imunoglobulina G/análise , Animais , Anticorpos Imobilizados/química , Antígenos/química , Antígenos/imunologia , Óxido Ferroso-Férrico/química , Fluoresceína-5-Isotiocianato/química , Fluorescência , Corantes Fluorescentes/química , Imunoensaio , Imunoglobulina G/química , Fenômenos Magnéticos , Nanopartículas/química , Albumina Sérica/química , Albumina Sérica/imunologia , Dióxido de Silício/química , SuínosRESUMO
Glutathione-capped water-soluble CuInS/ZnS quantum dots (QDs) were prepared by a microwave-assisted method. Their fluorescence, with excitation/emission peaks at 380/570 nm, is found to be quenched by hydrogen peroxide (H2O2) that is produced by the uricase catalyzed oxidation of uric acid (UA) and oxygen. The findings are used in a quenchometric method for the determination of UA. The effects of different ligands on the QDs, of pH value, buffers, enzyme ratio and reaction time were optimized. The detection limit for UA is 50 nM which is lower than other QD-based method, and the detection ranges extends from 0.25-4.0 µM. The assay is simple and sensitive, and no further modification of the QDs is required. Graphical abstract á .
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Early diagnosis of chronic, critical diseases improves clinical outcomes, and biomarkers play an important role as an indicator of severity or presence of a disease. Alkaline phosphatase (ALP) is one such vital biomarker in the diagnosis of several diseases. Herein we introduce a facile, sensitive fluorescent assay, based on the inner filter effect (IFE), for ALP activity determination in serum and in living cells. It is well known that the key to maximize the sensitivity of an IFE-based fluorescence assays is to broaden the overlap between the absorption of an absorber and the excitation/emission of a fluorophore. We employed CuInS/ZnS quantum dots (CIS/ZnS QDs) and p-nitrophenylphosphate (PNPP) as the fluorescent indicator and the substrate, respectively, for ALP activity assessment. Due to the CIS/ZnS QDs have an efficient excitation at 405â¯nm, meanwhile with a large Stokes shift emission at 588â¯nm, p-nitrophenol (PNP) with absorption peak at 405â¯nm, the hydrolyzed produce of PNPP and ALP, can act as a competitive absorber to absorb the excitation light of CIS/ZnS QDs, resulting in noticeable quenching of CIS/ZnS QDs. The proposed sensor detects ALP activity in human serum samples (sample consumption: 20⯵L) with detection limit of 0.01â¯Uâ¯L-1. Excellent biocompatibility of CIS/ZnS QDs enables the sensor to monitor endogenous ALP in living cells. Furthermore, because the surface modification or the linking between the receptor and the fluorophore is no longer required, this fluorescent sensing system has the potential to simplify ALP clinical measurement, thereby improving diagnostics of relevant diseases.
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Fosfatase Alcalina/metabolismo , Complexos de Coordenação/química , Imagem Molecular/métodos , Pontos Quânticos/química , Pontos Quânticos/metabolismo , Sulfetos/química , Água/química , Compostos de Zinco/química , Zinco/química , Linhagem Celular Tumoral , Sobrevivência Celular , Técnicas de Química Sintética , Humanos , Limite de DetecçãoRESUMO
The nearly complete mitochondrial genome of Paederus fuscipes (GenBank accession no. MG581161) is 17,644 bp in size, containing 13 protein-coding genes, 22 transfer RNAs, two ribosomal RNAs, and a partial control region. The gene order is similar to the typical insect mitochondrial genome. Maximum likelihood tree recovered the monophyly of Staphylininae, Pselaphinae, Paederinae and Aleocharinae. Additionally, Staphylininae is a sister group to Paederinae.
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MicroRNAs (miRNAs) are short single-stranded non-coding RNAs that regulate gene expression, particularly during development. In this study, 345 miRNAs were identified from the English green aphid, Sitobion avenae (F.), of which 168 were conserved and 177 were S. avenae-specific. Quantitative comparison of miRNA expression levels indicated that 16 and 12 miRNAs were significantly up-regulated in winged and wingless S. avenae small RNA libraries, respectively. Differential expression of these miRNAs was confirmed by real-time quantitative RT-PCR validation. The putative transcript targets for these candidate miRNAs were predicted based on sequences from a model species Drosophila melanogaster and four aphid species Acyrthosiphon pisum, Myzus persicae, Toxoptera citricida, and Aphis gosspii. Gene Ontology and KEGG pathway analyses shed light on the potential functions of these miRNAs in the regulation of genes involved in the metabolism, development and wing polyphenism of S. avenae.