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1.
Lasers Med Sci ; 39(1): 233, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39235691

RESUMEN

Clearance of comedone is challenging in the treatment of acne, as it is very likely to develop into inflammatory lesions. However, there is lack of effective treatments for dense comedones. Comedone extractor has been widely employed by dermatologists, but the effect is temporary and may cause irritation. CO2 laser is a potential method for dense comedones, but the efficacy and safety need to be explored. In this single-center, randomized, single-blind, self-controlled study, the faces of patients with dense comedones were randomly assigned into two sides receiving either ultra-pulse dynamic CO2 laser or comedone extraction at an interval of 2 weeks for 4 sessions. After 4 treatments, the average comedone reduction rate of the CO2 laser was 64.49%, which was higher than that by the extractor (46.36%) (P < .001). 79.16% of the patients reached over 50% reduction by CO2 laser, while only 37.5% on extractor treated side reached 50% clearance. Texture index, porphyrin index, red zone, erythema index, and transepidermal water loss decreased after both treatments, and CO2 laser showed more improvement. There was no difference in hydration index and melanin index between the two treatments. No permanent or severe side effects were observed on both sides. The CO2 laser showed higher comedone clearance with lower pain scores than the comedone extractor.


Asunto(s)
Acné Vulgar , Láseres de Gas , Humanos , Láseres de Gas/uso terapéutico , Método Simple Ciego , Masculino , Femenino , Acné Vulgar/radioterapia , Adulto , Estudios Prospectivos , Adulto Joven , Resultado del Tratamiento , Adolescente
2.
J Am Chem Soc ; 146(31): 21348-21356, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-38905206

RESUMEN

Quantum dots (QDs) exhibit superior brightness and photochemical stability, making them the preferred option for highly sensitive single-molecule detection compared with fluorescent dyes or proteins. Nevertheless, their high surface energy leads to nonspecific adsorption and poor colloidal stability. In the past decades, we have found that QD-based fluorescent nanoparticles (FNs) can not only address these limitations but also enhance detection sensitivity. However, the photoluminescence quantum yield (PLQY) of FNs is significantly lower compared with that of original QDs. It is urgent to develop a strategy to solve the issue, aiming to further enhance detection sensitivity. In this study, we found that the decrease of PLQY of FNs prepared by free radical polymerization was attributed to two factors: (1) generation of defects that can cause nonradiative transitions resulting from QD-ligands desorption and QD-shell oxidation induced by free radicals; (2) self-absorption resulting from aggregation caused by incompatibility of QDs with polymers. Based on these, we proposed a multihierarchical regulation strategy that includes: (1) regulating QD-ligands; (2) precisely controlling free radical concentration; and (3) constructing cross-linked structures of polymer to improve compatibility and to reduce the formation of surface defects. It is crucial to emphasize that the simultaneous coordination of multiple factors is essential. Consequently, a world-record PLQY of 97.6% for FNs was achieved, breaking through the current bottleneck at 65%. The flexible application of this regulatory concept paves the way for the large-scale production of high-brightness QD-polymer complexes, enhancing their potential applications in sensitive biomedical detection.

3.
Adv Mater ; 36(18): e2311457, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38243660

RESUMEN

The extracellular space (ECS) is an important barrier against viral attack on brain cells, and dynamic changes in ECS microstructure characteristics are closely related to the progression of viral encephalitis in the brain and the efficacy of antiviral drugs. However, mapping the precise morphological and rheological features of the ECS in viral encephalitis is still challenging so far. Here, a robust approach is developed using single-particle diffusional fingerprinting of quantum dots combined with machine learning to map ECS features in the brain and predict the efficacy of antiviral encephalitis drugs. These results demonstrated that this approach can characterize the microrheology and geometry of the brain ECS at different stages of viral infection and identify subtle changes induced by different drug treatments. This approach provides a potential platform for drug proficiency assessment and is expected to offer a reliable basis for the clinical translation of drugs.


Asunto(s)
Antivirales , Encefalitis Viral , Espacio Extracelular , Aprendizaje Automático , Puntos Cuánticos , Antivirales/química , Antivirales/farmacología , Antivirales/uso terapéutico , Espacio Extracelular/metabolismo , Animales , Puntos Cuánticos/química , Encefalitis Viral/tratamiento farmacológico , Ratones , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Reología , Humanos
4.
Adv Mater ; 36(2): e2306808, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37732588

RESUMEN

The plasma membranes (PM) of mammalian cells contain diverse lipids, proteins, and carbohydrates that are important for systemic recognition and communication in health and disease. Cell membrane coating technology that imparts unique properties of natural plasma membranes to the surface of encapsulated nanoparticles is thus becoming a powerful platform for drug delivery, immunomodulation, and vaccination. However, current coating methods fail to take full advantage of the natural systems because they disrupt the complex and functionally essential features of PMs, most notably the chemical diversity and compositional differences of lipids in two leaflets of the PM. Herein, a new lipid coating approach is reported in which the lipid composition is optimized through a combination of biomimetic and systematic variation approaches for the custom design of nanocarrier systems for precision drug delivery. Nanocarriers coated with the optimized lipids offer unique advantages in terms of bioavailability and efficiency in tumor targeting, tumor penetration, cellular uptake, and drug release. This pilot study provides new insight into the rational design and optimization of nanocarriers for cancer chemotherapeutic drugs and lays the foundation for further customization of cell membrane-mimicking nanocarriers through systematic incorporation of other components.


Asunto(s)
Nanopartículas , Neoplasias , Animales , Membrana Celular/metabolismo , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Lípidos/química , Mamíferos , Nanopartículas/química , Neoplasias/tratamiento farmacológico , Proyectos Piloto , Humanos
5.
Lasers Surg Med ; 55(9): 817-828, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37582350

RESUMEN

OBJECTIVES: Dense comedones are common in patients with acne vulgaris, and promoting treatment can prevent the progression of acne lesions. However, the efficacy-time conflict makes the treatment challenging and the medication options are limited by the side effects. MATERIALS AND METHODS: Thirty-five patients with symmetrical dense comedones were enrolled and the two sides of the face were randomly assigned to receive 30% supramolecular salicylic acid (SSA) combined with CO2 laser or CO2 laser monotherapy at an interval of 2 weeks for six treatment sessions. Comedones count, porphyrin index (PI), texture index (TI), melanin index, erythema index, hydration index (HI), transepidermal water loss (TEWL), and side effects were recorded at each visit till the 12th week. RESULTS: Thirty-one patients completed the study. Comedones on the combined-SSA side were reduced more after six treatments, that the mean reduction rate of the combined-SSA side was 85.76%, and that of the CO2 laser-treated side was 62.32% (Pbetween < 0.001). Combining SSA also showed a better effect on reducing PI and TI than CO2 laser singly (Pbetween < 0.001). TEWL and HI between the two sides showed no significant differences after treatments. No permanent or severe side effects were observed on both side. CONCLUSIONS: The treatment combined CO2 laser with 30% SSA dealt with the efficacy-time conflict while significantly reducing comedones and improving skin texture in 12 weeks and no serious adverse reactions occurred. LIMITATIONS: It is a single-center study and the number of subjects was small.

6.
Nano Lett ; 22(22): 9163-9173, 2022 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-36374537

RESUMEN

Maximizing the therapeutic capacity of drugs by allowing them to escape lysosomal degradation is a long-term challenge for nanodrug delivery. Japanese encephalitis virus (JEV) has evolved the ability to escape the endosomal region to avoid degradation of internal genetic material by lysosomes and further induce upregulation of cellular autophagy for the purpose of their mass reproduction. In this work, to exploit the lysosome escape and autophagy-inducing properties of JEV for cancer therapy, we constructed a virus-mimicking nanodrug consisting of anti-PDL1 antibody-decorated JEV-mimicking virosome encapsulated with a clinically available autophagy inhibitor, hydroxychloroquine (HCQ). Our study indicated that the nanodrug can upregulate the autophagy level and inhibit the autophagic flux, thereby inducing the apoptosis of tumor cells, and further activating the immune response, which can greatly improve the antitumor and tumor metastasis suppression effects and provide a potential therapeutic strategy for tumor treatment.


Asunto(s)
Nanopartículas , Neoplasias , Autofagia , Lisosomas/metabolismo , Apoptosis , Hidroxicloroquina/farmacología , Hidroxicloroquina/uso terapéutico , Nanopartículas/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo
7.
3 Biotech ; 12(11): 327, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36276474

RESUMEN

"Saccharum complex" is a hypothetical group of species, which is supposed to be involved in the origin of modern sugarcane, and displays large genomes and complex chromosomal alterations. The utilization of restricted parents in breeding programs of modern cultivated sugarcane has resulted in a genetic blockage, which controlled its improvement because of the limited genetic diversity. The use of wild relatives is an effective way to broaden the genetic composition of cultivated sugarcane. Due to the infrequent characterization of genomes, the potential of wild relatives is diffused in improving the cultivated sugarcane. To characterize the genomes of the wild relatives, the genome size and phylogenetic relationships among eight species, including Saccharum spontaneum, Erianthus arundinaceus, E. fulvus, E. rockii, Narenga porphyrocoma, Miscanthus floridulus, Eulalia quadrinervis, and M. sinensis were evaluated based on flow cytometry, genome surveys, K-mer analysis, chloroplast genome sequencing, and whole-genome SNPs analysis. We observed highly heterozygous genomes of S. spontaneum, E. rockii, and E. arundinaceus and the highly repetitive genome of E. fulvus. The genomes of Eulalia quadrinervis, N. porphyrocoma, M. sinensis, and M. floridulus were highly complex. Phylogenetic results of the two approaches were dissimilar, however, both indicate E. fulvus displayed closer relationships to Miscanthus and Saccharum than other species of Saccharum complex. Eulalia quadrinervis was more closely related to M. floridulus than M. sinensis; E. arundinaceus differ significantly from Miscanthus, Narenga, and Saccharum, but was relatively close to Erianthus. We proved the point of E. rockii and E. fulvus should not be classified as one genus, and E. fulvus should be classified as the Saccharum genus. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-022-03338-5.

8.
World J Gastrointest Oncol ; 14(4): 872-886, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35582102

RESUMEN

BACKGROUND: The phosphoinositide 3-kinase/protein kinase-B/mechanistic target of rapamycin (PI3K/Akt/mTOR) signalling pathway is crucial for cell survival, differentiation, apoptosis and metabolism. Xihuang pills (XHP) are a traditional Chinese preparation with antitumour properties. They inhibit the growth of breast cancer, glioma, and other tumours by regulating the PI3K/Akt/mTOR signalling pathway. However, the effects and mechanisms of action of XHP in hepatocellular carcinoma (HCC) remain unclear. Regulation of the PI3K/Akt/mTOR signalling pathway effectively inhibits the progression of HCC. However, no study has focused on the XHP-associated PI3K/Akt/mTOR signalling pathway. Therefore, we hypothesized that XHP might play a role in inhibiting HCC through the PI3K/Akt/mTOR signalling pathway. AIM: To confirm the effect of XHP on HCC and the possible mechanisms involved. METHODS: The chemical constituents and active components of XHP were analysed using ultra-performance liquid chromatography-quadrupole time of flight mass spectrometry (UPLC-Q-TOF-MS). Cell-based experiments and in vivo xenograft tumour experiments were utilized to evaluate the effect of XHP on HCC tumorigenesis. First, SMMC-7721 cells were incubated with different concentrations of XHP (0, 0.3125, 0.625, 1.25, and 2.5 mg/mL) for 12 h, 24 h and 48 h. Cell viability was assessed using the CCK-8 assay, followed by an assessment of cell migration using a wound healing assay. Second, the effect of XHP on the apoptosis of SMMC-7721 cells was evaluated. SMMC-7721 cells were stained with fluorescein isothiocyanate and annexin V/propidium iodide. The number of apoptotic cells and cell cycle distribution were measured using flow cytometry. The cleaved protein and mRNA expression levels of caspase-3 and caspase-9 were detected using Western blotting and quantitative reverse-transcription polymerase chain reaction (RT-qPCR), respectively. Third, Western blotting and RT-qPCR were performed to confirm the effects of XHP on the protein and mRNA expression of components of the PI3K/Akt/mTOR signalling pathway. Finally, the effects of XHP on the tumorigenesis of subcutaneous hepatocellular tumours in nude mice were assessed. RESULTS: The following 12 compounds were identified in XHP using high-resolution mass spectrometry: Valine, 4-gingerol, myrrhone, ricinoleic acid, glycocholic acid, curzerenone, 11-keto-ß-boswellic acid, oleic acid, germacrone, 3-acetyl-9,11-dehydro-ß-boswellic acid, 5ß-androstane-3,17-dione, and 3-acetyl-11-keto-ß-boswellic acid. The cell viability assay results showed that treatment with 0.625 mg/mL XHP extract decreased HCC cell viability after 12 h, and the effects were dose- and time-dependent. The results of the cell scratch assay showed that the migration of HCC cells was significantly inhibited in a time-dependent manner by the administration of XHP extract (0.625 mg/mL). Moreover, XHP significantly inhibited cell migration and resulted in cell cycle arrest and apoptosis. Furthermore, XHP downregulated the PI3K/Akt/mTOR signalling pathway, which activated apoptosis executioner proteins (e.g., caspase-9 and caspase-3). The inhibitory effects of XHP on HCC cell growth were determined in vivo by analysing the tumour xenograft volumes and weights. CONCLUSION: XHP inhibited HCC cell growth and migration by stimulating apoptosis via the downregulation of the PI3K/Akt/mTOR signalling pathway, followed by the activation of caspase-9 and caspase-3. Our findings clarified that the antitumour effects of XHP on HCC cells are mediated by the PI3K/Akt/mTOR signalling pathway, revealing that XHP may be a potential complementary therapy for HCC.

9.
World J Gastrointest Oncol ; 14(2): 450-477, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-35317323

RESUMEN

BACKGROUND: In traditional Chinese medicine (TCM), frankincense and myrrh are the main components of the antitumor drug Xihuang Pill. These compounds show anticancer activity in other biological systems. However, whether frankincense and/or myrrh can inhibit the occurrence of hepatocellular carcinoma (HCC) is unknown, and the potential molecular mechanism(s) has not yet been determined. AIM: To predict and determine latent anti-HCC therapeutic targets and molecular mechanisms of frankincense and myrrh in vivo. METHODS: In the present study, which was based on the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (http://tcmspw.com/tcmsp.php), Universal Protein database (http://www.uniprot.org), GeneCards: The Human Gene Database (http://www.genecards.org/) and Comparative Toxicogenomics Database (http://www.ctdbase.org/), the efficacy of and mechanism by which frankincense and myrrh act as anti-HCC compounds were predicted. The core prediction targets were screened by molecular docking. In vivo, SMMC-7721 human liver cancer cells were transplanted as xenografts into nude mice to establish a subcutaneous tumor model, and two doses of frankincense plus myrrh or one dose of an EGFR inhibitor was administered to these mice continuously for 14 d. The tumors were collected and evaluated: the tumor volume and growth rate were gauged to evaluate tumor growth; hematoxylin-eosin staining was performed to estimate histopathological changes; immunofluorescence (IF) was performed to detect the expression of CD31, α-SMA and collagen IV; transmission electron microscopy (TEM) was conducted to observe the morphological structure of vascular cells; enzyme-linked immunosorbent assay (ELISA) was performed to measure the levels of secreted HIF-1α and TNF-α; reverse transcription-polymerase chain reaction (RT-qPCR) was performed to measure the mRNA expression of HIF-1α, TNF-α, VEGF and MMP-9; and Western blot (WB) was performed to determine the levels of proteins expressed in the EGFR-mediated PI3K/Akt and MAPK signaling pathways. RESULTS: The results of the network pharmacology analysis showed that there were 35 active components in the frankincense and myrrh extracts targeting 151 key targets. The molecular docking analysis showed that both boswellic acid and stigmasterol showed strong affinity for the targets, with the greatest affinity for EGFR. Frankincense and myrrh treatment may play a role in the treatment of HCC by regulating hypoxia responses and vascular system-related pathological processes, such as cytokine-receptor binding, and pathways, such as those involving serine/threonine protein kinase complexes and MAPK, HIF-1 and ErbB signaling cascades. The animal experiment results were verified. First, we found that, through frankincense and/or myrrh treatment, the volume of subcutaneously transplanted HCC tumors was significantly reduced, and the pathological morphology was attenuated. Then, IF and TEM showed that frankincense and/or myrrh treatment reduced CD31 and collagen IV expression, increased the coverage of perivascular cells, tightened the connection between cells, and improved the shape of blood vessels. In addition, ELISA, RT-qPCR and WB analyses showed that frankincense and/or myrrh treatment inhibited the levels of hypoxia-inducible factors, inflammatory factors and angiogenesis-related factors, namely, HIF-1α, TNF-α, VEGF and MMP-9. Furthermore, mechanistic experiments illustrated that the effect of frankincense plus myrrh treatment was similar to that of an EGFR inhibitor with regard to controlling EGFR activation, thereby inhibiting the phosphorylation activity of its downstream targets: the PI3K/Akt and MAPK (ERK, p38 and JNK) pathways. CONCLUSION: In summary, frankincense and myrrh treatment targets tumor blood vessels to exert anti-HCC effects via EGFR-activated PI3K/Akt and MAPK signaling pathways, highlighting the potential of this dual TCM compound as an anti-HCC candidate.

10.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-955623

RESUMEN

Objective:To explore the role of multimedia teaching based on post competency in practical teaching of pediatrics.Methods:A total of 64 pediatric interns received by our unit from January 2019 to October 2020 were studied and randomly divided into two groups. Traditional clinical teaching was used in the control group, and multimedia teaching based on post competency was used in the experimental group. The assessment results of pediatrics-related theoretical knowledge and practical skills, post competency and recognition of teaching were compared between the two groups before and after teaching. SPSS 26.0 was used for t-test and chi-square test. Results:After teaching, the examination results of the two groups of interns' pediatrics-related theoretical knowledge and practical operation skills were higher than those before teaching [(98.72±1.29) vs. (79.84±3.96), (97.94±2.17) vs. (70.22±4.17)], and the above results of the experimental group were higher than those of the control group [(98.72±1.29) vs. (90.22±3.46), (97.94±2.17) vs. (87.38±5.07)] ( P<0.05); the post competency scores of clinical diagnosis and treatment ability, clinical operation skills, self-learning and information technology, and medical humanistic quality of the two groups after teaching were higher than those before teaching, and the scores of the experimental group were higher than those of the control group ( P<0.05); the recognition rate of the teaching method in stimulating learning interest, improving learning effect, enhancing doctor-patient communication ability, rasing clinical thinking ability, and strenthening professional confidence in the experimental group was higher than that in the control group ( P<0.05). Conclusion:The application of multimedia teaching based on post competency in the practical teaching of pediatrics can not only improve the examination results and various aspects of post competency, but also be recognized by interns.

11.
Anal Chem ; 93(15): 6128-6134, 2021 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-33834764

RESUMEN

Cardiovascular disease is one of the main causes of death in the world, which is closely associated with dyslipidemia. Dyslipidaemia is usually manifested as a relatively higher level of low-density lipoprotein (LDL) and lower level of high-density lipoprotein (HDL). Thus, the quantitative detection of the LDL and HDL particles is of great importance to predict the risk of cardiovascular diseases. However, the traditional methods can only indirectly reflect the HDL/LDL particle concentrations by detecting the cholesterol or proteins in HDL/LDL particles and are always laborious and time-consuming. Thus, the accurate and efficient approach for the detection of intact HDL and LDL particles is still lacking so far. We developed an enzyme- and isolation-free method to measure the concentration of HDL and LDL based on DNAzyme and hybridization chain reaction (HCR)-based signal amplification. This method can be used to directly and accurately detect the concentration of "actual" HDL and LDL particles instead of the cholesterol in HDL and LDL, with limits of detection of 10 and 30 mg/dL, respectively, which also satisfied the lipoprotein analysis in clinical samples. Therefore, this HCR-DNAzyme platform has great potential in clinical applications and health management.


Asunto(s)
Enfermedades Cardiovasculares , ADN Catalítico , Dislipidemias , HDL-Colesterol , LDL-Colesterol , Humanos , Triglicéridos
12.
Aging Dis ; 11(4): 791-800, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32765946

RESUMEN

To explore the underlying pathogenic mechanism of Parkinson's disease (PD) with concomitant postural abnormalities (PDPA) through the relationship between its gait and brain function characteristics. PD patients from the neurology outpatient clinic at Ruijin Hospital were recruited and grouped according to whether postural abnormalities (including camptocormia and Pisa syndrome) were present. PD-related scale assessments, three-dimensional gait tests and brain resting-state functional magnetic imaging were performed and analyzed. The gait characteristics independently associated with PDPA were decreased pelvic obliquity angle and progressive downward movement of the center of mass during walking. PDPA features included decreased functional connectivity between the left insula and bilateral supplementary motor area, which was significantly correlated with reduced Berg Balance Scale scores. Functional connectivity between the right insula and bilateral middle frontal gyrus was decreased and significantly correlated with a decreased pelvic obliquity angle and poor performance on the Timed Up and Go test. Moreover, through diffusion tensor imaging analysis, the average fractional anisotropy value of the fibers connecting the left insula and left supplementary motor area was shown to be decreased in PDPA. There is decreased functional connectivity among the insula, supplementary motor area and middle frontal gyrus with structural abnormalities between the left insula and the left supplementary motor area; these changes in brain connectivity are probably among the causes of gait dysfunction in PDPA and provide some clues regarding the pathogenic mechanisms of PDPA.

13.
Talanta ; 203: 248-254, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31202334

RESUMEN

Metal-organic frameworks (MOFs) are hotly investigated as a novel kind of fluorescent sensing materials in recent years. However, the application of MOF sensing to drug analysis is still very difficult yet, because the structural similarity among drug homolog-ues exceeds the discrimination ability of MOFs. Array sensing technique, which relies on the combined responses of a group of sensing materials, is a viable way to solve this problem. In this work, we chose five luminescent MOFs with different fluorophores to construct a fluorescent sensor array for the analysis of flavonoids. With the response pattern of these MOFs and the statistical methods of linear discriminant analysis and hierarchical cluster analysis, nine flavonoids with similar structures were correctly discriminated. By the combination with UV spectrum, our method could even realize the qualification and quantification of the flavonoid samples with unknown concentrations. This work is the first time of using MOFs to successfully distinguish multiple drug homolog-ues.


Asunto(s)
Flavonoides/análisis , Colorantes Fluorescentes/química , Estructuras Metalorgánicas/química , Análisis por Conglomerados , Análisis Discriminante , Transferencia Resonante de Energía de Fluorescencia/métodos , Colorantes Fluorescentes/síntesis química , Estructuras Metalorgánicas/síntesis química , Té/química
14.
Dalton Trans ; 48(17): 5705-5712, 2019 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-30968928

RESUMEN

The sensing performance of metal-organic frameworks (MOFs), a novel kind of crystalline fluorescent sensing materials, would be profoundly affected by their backbone structures. The current understanding about the backbone effect is limited to the modulation of analyte accommodation through pore structures. Herein, three topologically different pyrene-based MOFs, including NU-1000, NU-901 and ROD-7, were investigated as potential fluorescent sensors for polycyclic aromatic hydrocarbons (PAHs). Although these MOFs are constructed by the same photoactive component, they exhibited distinct sensing behaviors. NU-1000 gave different forms of fluorescent response to acenaphthylene, pyrene and fluoranthene with detection limits at the ng L-1 level. In contrast, NU-901 and ROD-7 were unresponsive to all tested PAHs. Experimental and computational investigations illustrate that this distinction is due to the variance in the excited state energy. The strong inter-ligand interaction in NU-901 and ROD-7 lowers their excited state energy and thus thermodynamically inhibits the photo-induced electron transfer and excimer/exciplex formation, which works in the NU-1000 system. This work proves for the first time that the topological structure of MOFs could affect their sensing performance in an energetic way.

15.
Analyst ; 144(6): 1916-1922, 2019 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-30681671

RESUMEN

Antibiotics have been noted as an important class of emerging contaminants in the environment. Metal-organic frameworks (MOFs), which have been intensely investigated as a novel kind of sensing material, have been tentatively applied to the detection of antibiotics in recent years. In this work, a nanoscale MOF (In-sbdc) with a strong (quantum yield = 13%) and stable emission in water was synthesized. With its effective spectral overlap with tetracyclines, adsorption preconcentration and the usage of a masking agent, In-sbdc gave sensitive responses to a series of tetracycline antibiotics (tetracycline, chlorotetracycline and oxytetracycline) with detection limits of 0.28-0.30 µM, but another eight tested kinds of antibiotics did not cause a remarkable change in its emission (<10% of the response caused by an equal amount of tetracyclines). This MOF-based sensing system was successfully applied to tetracyclines detection in a series of actual water and food samples.


Asunto(s)
Antibacterianos/análisis , Técnicas Biosensibles , Monitoreo del Ambiente/métodos , Análisis de los Alimentos/métodos , Estructuras Metalorgánicas/química , Tetraciclinas/análisis , Contaminantes Químicos del Agua/análisis , Fluorescencia , Límite de Detección
16.
Talanta ; 183: 83-88, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29567192

RESUMEN

The activity assay of xanthine oxidase (XO) is of great application value in clinical diagnosis because the abnormal level of this enzyme is related to a series of pathological states. In this work, a Zr based metal-organic framework (BTB-MOF) with stable photoluminescence in pure water and buffer solution was synthesized. The examination about the fluorescent responses of this material to xanthine and its oxidation product, uric acid, showed that, although both of them affected the emission of BTB-MOF in quenching form, the efficiencies presented much difference. Taking advantage of this feature, a fluorescent method was developed for the activity assay of XO, that is, BTB-MOF was added to the enzymatic oxidation system as a sensor to transduce the proceeding of the reaction real-timely to the signal of fluorescent intensity change. Our method can work under the interference of normal biologically related species, and precisely reflect XO activity in the range of 0.2-40 U L-1 (detection limit = 0.004 U L-1). With consecutive fluorescence intensity scan, this assay could be applied as a high speed screening method of XO inhibitors with the testing time of 1 min. This work shows the wide potential application of MOFs in enzyme analysis.


Asunto(s)
Evaluación Preclínica de Medicamentos/métodos , Inhibidores Enzimáticos/farmacología , Colorantes Fluorescentes/química , Estructuras Metalorgánicas/química , Xantina Oxidasa/análisis , Circonio/química , Inhibidores Enzimáticos/química , Cinética , Estructuras Metalorgánicas/síntesis química , Tamaño de la Partícula , Espectrometría de Fluorescencia , Factores de Tiempo , Xantina Oxidasa/antagonistas & inhibidores , Xantina Oxidasa/metabolismo
17.
Chemistry ; 23(61): 15498-15504, 2017 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-28836296

RESUMEN

As novel fluorescent-sensing materials, metal-organic frameworks (MOFs) have shown great potential in environmental monitoring. However, most of the researches are limited to traditional pollutants, whereas the application of MOFs to the detection of the pollutants with more complicated structures, such as endocrine disrupting chemicals (EDCs), has rarely been explored. The difficulties faced in the sensing of EDCs include their electronic stability and the structural similarity among homologues, which could be overcome by the incorporation of enzymatic reaction. In this work, the first example of enzyme-assisted MOF-fluorescent-sensing was developed for the analysis of diethylstilbestrol (DES, a synthetic estrogen). In this system, DES is first oxidized by HRP/H2 O2 quantitatively to its quinone form, and then the quinone product is selectively captured by a stilbene based luminescent MOF to induce fluorescence response. By the tandem sensitization and filtration of enzymatic reaction and MOF adsorption, this method shows high sensitivity (DL=89 nm) and can distinguish DES from other similar-structured EDCs.

18.
Chaos ; 26(6): 065311, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27368800

RESUMEN

This study is concerned with the dynamic behaviors of epidemic spreading in multiplex networks. A model composed of two interacting complex networks is proposed to describe cooperative spreading processes, wherein the virus spreading in one layer can penetrate into the other to promote the spreading process. The global epidemic threshold of the model is smaller than the epidemic thresholds of the corresponding isolated networks. Thus, global epidemic onset arises in the interacting networks even though an epidemic onset does not arise in each isolated network. Simulations verify the analysis results and indicate that cooperative spreading processes in multiplex networks enhance the final infection fraction.


Asunto(s)
Epidemias , Modelos Teóricos , Humanos , Método de Montecarlo , Probabilidad
19.
Chaos ; 25(11): 113104, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26627564

RESUMEN

Synchronization of complex networks has been extensively investigated in various fields. In the real world, one network is usually affected by another one but coexists in harmony with it, which can be regarded as another kind of synchronization--generalized synchronization (GS). In this paper, the GS in two-layer complex networks with unidirectional inter-layer coupling via pinning control is investigated based on the auxiliary-system approach. Specifically, for two-layer networks under study, one is considered as the drive network and the other is the response one. According to the auxiliary-system approach, output from the drive layer is designed as input for the response one, and an identical duplication of the response layer is constructed, which is driven by the same driving signals. A sufficient condition for achieving GS via pinning control is presented. Numerical simulations are further provided to illustrate the correctness of the theoretical results. It is also revealed that the least number of pinned nodes needed for achieving GS decreases with the increasing density of the response layer. In addition, it is found that when the intra-layer coupling strength of the response network is large, nodes with larger degrees should be selected to pin first for the purpose of achieving GS. However, when the coupling strength is small, it is more preferable to pin nodes with smaller degrees. This work provides engineers with a convenient approach to realize harmonious coexistence of various complex systems, which can further facilitate the selection of pinned systems and reduce control cost.

20.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-235354

RESUMEN

<p><b>OBJECTIVE</b>To observe the effects of beta3-adrenergic receptor(beta3-AR) antagonist on myocardial uncoupling protein 2 (UCP2) expression and energy metabolism in chronic heart failure rats.</p><p><b>METHODS</b>Seven weight-matched normal adult rats (control group), 18 isoproterenol (ISO) induced heat failure (HR) rats (ISO group) and 21 ISO induced heart failure rats but received specific beta3-AR inhibitor SR59230A (ISO+ SR59230A group) for 6 weeks were included in this research. At the end of the study, echocardiography was performed, the ratio of left ventricular weight and body weight (LVW/BW) was calculated. The expression of beta3-AR ad UCP2 mRNA in myocardium were detected by reverse transcription-polymerase chain reaction (RT-PCR), the UCP2 protein in myocardium were detected by Western blot. The myocardial contents of creatine phosphate (PCr) and adenosine triphosphate (ATP) were measured by high performance liquid chromatography (HPLC).</p><p><b>RESULTS</b>Compared with control group, the cardiac function was significantly reduced and myocardial beta3-AR mRNA significantly increased, UCP2 mRNA and protein were also significantly increased in ISO group, this change could be attenuated by the treatment with SR59230A, and the expression of myocardial UCP2 protein negatively correlated with the ratio of PCr/ATP.</p><p><b>CONCLUSION</b>In the chronic stage of HF, the expression of UCP2 increases, which causes myocardial energy shortage, SR59230A improves myocardia energy efficiency and cardiac function by means of suppressing the expression of UCP2.</p>


Asunto(s)
Animales , Masculino , Ratas , Antagonistas Adrenérgicos , Farmacología , Metabolismo Energético , Insuficiencia Cardíaca , Metabolismo , Canales Iónicos , Metabolismo , Proteínas Mitocondriales , Metabolismo , Miocardio , Metabolismo , Ratas Wistar , Receptores Adrenérgicos beta 3 , Metabolismo , Proteína Desacopladora 2
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