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1.
Opt Express ; 32(1): 785-794, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38175098

RESUMO

Cavity optomechanical (COM) entanglement, playing an essential role in building quantum networks and enhancing quantum sensors, is usually weak and easily destroyed by noises. As feasible and effective ways to overcome this obstacle, optical or mechanical parametric modulations have been used to improve the quality of quantum squeezing or entanglement in various COM systems. However, the possibility of combining these powerful means to enhance COM entanglement has yet to be explored. Here, we fill this gap by studying a COM system containing an intra-cavity optical parametric amplifier (OPA), driven optically and mechanically. By tuning the relative strength and the frequency mismatch of optical and mechanical driving fields, we find that constructive interference can emerge and significantly improve the strength of COM entanglement and its robustness to thermal noises. This work sheds what we believe to be a new light on preparing and protecting quantum states with multi-field driven COM systems for diverse applications.

2.
Opt Express ; 32(12): 22020-22030, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38859542

RESUMO

We propose how to achieve chiral photon blockade by spinning a nonlinear optical resonator. We show that by driving such a device at a fixed direction, completely different quantum effects can emerge for the counter-propagating optical modes, due to the spinning-induced breaking of time-reversal symmetry, which otherwise is unattainable for the same device in the static regime. Also, we find that in comparison with the static case, robust non-classical correlations against random backscattering losses can be achieved for such a quantum chiral system. Our work, extending previous works on the spontaneous breaking of optical chiral symmetry from the classical to purely quantum regimes, can stimulate more efforts towards making and utilizing various chiral quantum effects, including applications for chiral quantum networks or noise-tolerant quantum sensors.

3.
Bioorg Chem ; 127: 105986, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35777232

RESUMO

Sinkianlignans A - D (1-4), four new sesquilignans with an unusual architectures was characterized with a rarely α-γ', ß-γ', and γ-γ' linkage pattern, and sinkianlignans E - F (5 and 6), two lignans, were isolated from the Ferula sinkiangensis. Hypothetic biosynthetic pathway of compound 3 contain a newly formed six-membered C-ring by Diels-Alder cycloaddition. The structures of isolates were established by spectroscopic techniques and computational methods. Biological evaluation of all the isolated compounds revealed that compounds 2a and 2b could inhibit IL-6 and TNF-α production in lipopolysaccharide (LPS) induced RAW264.7 cells in a dose-dependent manner.


Assuntos
Ferula , Sesquiterpenos , Anti-Inflamatórios/farmacologia , Ferula/química , Estrutura Molecular , Resinas Vegetais , Sesquiterpenos/química
4.
Sheng Li Xue Bao ; 74(6): 970-978, 2022 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-36594385

RESUMO

The aim of this study was to explore the regulating effects of hyperoside (Hyp) on lipid metabolism in high-fat diet mice. The high-fat diet mouse model was established by high-fat diet induction. After 5 weeks of Hyp intragastric administration in high-fat diet mice, the serum lipid levels before and after Hyp administration were measured by the corresponding kits. The tissue structure of mouse liver was observed by HE staining before and after Hyp administration. The changes of intestinal flora and transcriptome were measured by Illumina platforms. Liquid chromatography-mass spectrometry (LC-MS) was used to determine non-targeted metabolites. The results showed that Hyp significantly reduced lipid levels in the high-fat diet mice and effectively restored the external morphology and internal structure of liver tissue. Hyp changed the species composition of the intestinal flora in high-fat diet mice, increased the abundance of beneficial flora such as Ruminococcus, and decreased the abundance of harmful flora such as Sutterella. Combined multi-omics analysis revealed that the effect of retinoic acid on lipid metabolism was significant in the high-fat diet mice treated with Hyp, while the increase of retinoic acid content was significantly negatively correlated with the expression of genes such as cyp1a2 and ugt1a6b, positively correlated with AF12 abundance, and significantly negatively correlated with unidentified_Desulfovibrionaceae abundance. These results suggest that Hyp may modulate the abundance of AF12, unidentified_Desulfovibrionaceae and inhibit the expression of genes such as cyp1a2 and ugt1a6b, thus increasing the content of retinoic acid and regulating lipid metabolism in the high-fat diet mice.


Assuntos
Dieta Hiperlipídica , Metabolismo dos Lipídeos , Animais , Camundongos , Dieta Hiperlipídica/efeitos adversos , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP1A2/farmacologia , Multiômica , Fígado , Lipídeos/farmacologia , Tretinoína/metabolismo , Tretinoína/farmacologia , Camundongos Endogâmicos C57BL
5.
Am J Emerg Med ; 50: 136-141, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34365062

RESUMO

BACKGROUND: Foreign body(FB) ingestion in the upper digestive tract is a common emergency that lacks sufficient attention in adult population. Improper management may bring additional injuries and financial burdens to patients. This review was performed to determine the clinical characteristics of upper gastrointestinal FBs, including the demographic of adult patients, the type and location of FBs, underlying diseases of patients and other risk factors, and outcomes. METHODS: We searched PubMed, MEDLINE, EMBASE and Cochrane databases with the terms "foreign body AND upper gastrointestinal NOT child". Finally, we got 7 articles between 2001 and 2020 and extracted the information. RESULTS: A total of 1391 patients were included. 736 (52.9%) patients were males and 655 (47.1%) were females. Fish bone was the most common type of FBs. Esophagus accounts for the most location in the upper digestive tract. 18.2% (235/1291) patients had the underlying diseases, and 11.7% (58/494) had other risk factors. The overall complication rate was 4.5% (63/1391).


Assuntos
Serviço Hospitalar de Emergência , Corpos Estranhos/diagnóstico , Corpos Estranhos/etiologia , Trato Gastrointestinal Superior , Adulto , Humanos , Fatores de Risco
6.
Phys Rev Lett ; 125(14): 143605, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33064545

RESUMO

We propose how to achieve nonreciprocal quantum entanglement of light and motion and reveal its counterintuitive robustness against random losses. We find that by splitting the counterpropagating lights of a spinning resonator via the Sagnac effect, photons and phonons can be entangled strongly in a chosen direction but fully uncorrelated in the other. This makes it possible both to realize quantum nonreciprocity even in the absence of any classical nonreciprocity and also to achieve significant entanglement revival against backscattering losses in practical devices. Our work provides a way to protect and engineer quantum resources by utilizing diverse nonreciprocal devices, for building noise-tolerant quantum processors, realizing chiral networks, and backaction-immune quantum sensors.

7.
Am J Emerg Med ; 37(5): 828-831, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30060965

RESUMO

BACKGROUND: Skin flap-like wounds are common. These wound flaps are prone to avascular necrosis with simple debrided and sutured, and postoperative hyperplastic scarring and contracture of wound surfaces can adversely affect the patient's appearance. Here, we evaluate the data of cases with flap-like wounds to identify the causes of flap necrosis. METHODS: Six hundred patients with skin flap-like wounds between January 1, 2013 and December 31, 2016 were retrospectively reviewed. Their age, sex, injury reason, size of flap, length-width ratio of wound, thickness of pedicle, operation time, injury site, direction of blood perfusion in the flap and operating methods were recorded. The risks for flap necrosis were analyzed with one-factor analysis. RESULTS: A total success rate of 92.5% (555/600) for flap-like wound reconstruction was obtained. Among 67 flaps with vascular crisis, 22 were salvaged by subcutaneous injection of anisodamine, selective suture removal, and pressure dressing with elastic bandages. For the 45 patients with flap necrosis, there was no significant difference from patients without necrosis in terms of sex, age, and size of flap (P > 0.05). The incidence of flap necrosis was significantly different in terms of injury reason, length-width ratio of wound, thickness of pedicle, operation time, injury site, direction of blood perfusion in the flap and operating methods (P < 0.05). CONCLUSION: Injury reason, length-width ratio of wound, thickness of pedicle, operation time, injury site, direction of blood perfusion in the flap and operating methods, rather than age, sex and size of flap, were significant risk factors for necrosis of flap-like wounds.


Assuntos
Necrose/prevenção & controle , Procedimentos de Cirurgia Plástica/métodos , Lesões dos Tecidos Moles/cirurgia , Técnicas de Sutura , Adulto , Desbridamento/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Retalhos Cirúrgicos/irrigação sanguínea , Retalhos Cirúrgicos/cirurgia
8.
J Theor Biol ; 416: 81-87, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28077336

RESUMO

Predicting protein submitochondrial locations has been studied for about ten years. A dozen of methods were developed in this regard. Although a mitochondrion has four submitochondrial compartments, all existing studies considered only three of them. The mitochondrial intermembrane space proteins were always excluded in these studies. However, there are over 50 mitochondrial intermembrane space proteins in the recent release of UniProt database. We think it is time to incorporate these proteins in predicting protein submitochondrial locations. We proposed the functional domain enrichment score, which can be used as an enhancement to our positional-specific physicochemical properties method. We constructed a high-quality working dataset from the UniProt database. This dataset contains proteins from all four submitochondrial locations. Proteins with multiple submitochondrial locations are also included. Our method achieved over 70% prediction accuracy for proteins with single location on this dataset. On the M3-317 benchmarking dataset, our method achieved comparable prediction performance to other state-of-the-art methods. Our results indicate that the intermembrane space proteins can be incorporated in predicting protein submitochondrial locations. By evaluating our method with the proteins that have multiple submitochondrial locations, we conclude that our method is capable of predicting multiple submitochondrial locations. This is the first report of ab initio methods that can identify intermembrane space proteins. This is also the first attempt to incorporate proteins with multiple submitochondrial locations. The benchmarking dataset can be obtained by emails to the corresponding author.


Assuntos
Mitocôndrias/metabolismo , Proteínas/metabolismo , Proteômica/métodos , Sequência de Aminoácidos , Aminoácidos/química , Animais , Fenômenos Químicos , Biologia Computacional/métodos , Bases de Dados de Proteínas , Humanos , Mitocôndrias/química , Mitocôndrias/ultraestrutura , Membranas Mitocondriais , Proteínas/química
9.
J Theor Biol ; 402: 38-44, 2016 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-27155042

RESUMO

Recently, several efforts have been made in predicting Golgi-resident proteins. However, it is still a challenging task to identify the type of a Golgi-resident protein. Precise prediction of the type of a Golgi-resident protein plays a key role in understanding its molecular functions in various biological processes. In this paper, we proposed to use a mutual information based feature selection scheme with the general form Chou's pseudo-amino acid compositions to predict the Golgi-resident protein types. The positional specific physicochemical properties were applied in the Chou's pseudo-amino acid compositions. We achieved 91.24% prediction accuracy in a jackknife test with 49 selected features. It has the best performance among all the present predictors. This result indicates that our computational model can be useful in identifying Golgi-resident protein types.


Assuntos
Algoritmos , Aminoácidos/química , Biologia Computacional/métodos , Complexo de Golgi/metabolismo , Bases de Dados de Proteínas
10.
J Theor Biol ; 391: 35-42, 2016 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-26702543

RESUMO

Knowing the type of a Golgi-resident protein is an important step in understanding its molecular functions as well as its role in biological processes. In this paper, we developed a novel computational method to predict Golgi-resident protein types using positional specific physicochemical properties and analysis of variance based feature selection methods. Our method achieved 86.9% prediction accuracy in leave-one-out cross-validations with only 59 features. Our method has the potential to be applied in predicting a wide range of protein attributes.


Assuntos
Complexo de Golgi , Proteínas , Análise de Sequência de Proteína/métodos , Animais , Complexo de Golgi/genética , Complexo de Golgi/metabolismo , Humanos , Proteínas/genética , Proteínas/metabolismo
11.
Sheng Li Xue Bao ; 66(2): 223-30, 2014 Apr 25.
Artigo em Zh | MEDLINE | ID: mdl-24777414

RESUMO

The phosphatidylinositol 3-kinase (PI3K) and its downstream target protein kinase B (Akt/PKB) can be activated by a variety of extracellular and intracellular signals. They are important signaling molecules and key survival factors involved in cell proliferation, differentiation, apoptosis and other cellular processes. Recently, many reports demonstrate that type I PI3K/Akt signaling pathway plays an important role in maintenance of self-renewal and pluripotency of embryonic stem (ES) cells. Further studies with regard to the self-renewal and pluripotency of ES cells and underlying molecular mechanisms are crucial to its application in cell replacement therapy, regenerative medicine and tissue engineering. The present review focuses on the recent progress on the mediation of PI3K/Akt signaling pathway on the maintenance of self-renewal and pluripotency of ES cells.


Assuntos
Células-Tronco Embrionárias/citologia , Fosfatidilinositol 3-Quinases/fisiologia , Células-Tronco Pluripotentes/citologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Transdução de Sinais , Diferenciação Celular , Proliferação de Células , Humanos
12.
Sheng Li Xue Bao ; 66(6): 709-17, 2014 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-25516520

RESUMO

Cardiac extracellular matrix (ECM), generated from the process of decellularization, has been widely considered as an ideal source of biological scaffolds. However, current ECM preparations are generally difficult to be applied to generate cardiac tissue. Our research was aimed to improve decellularization protocols to prepare cardiac ECM slices. Adult murine ventricular tissues were embedded in low melting agarose and cut into 300 µm slices, and then were divided randomly into three groups: normal cardiac tissue, SDS treated group (0.1% SDS) and SDS+Triton X-100 treated group (0.1% SDS+0.5% Triton X-100). Total RNA content and protein content quantification, HE staining and immunostaining were used to evaluate the removal of cell components and preservation of vital ECM components. Furthermore, murine embryonic stem cell-derived cardiomyocytes (mES-CMs) and mouse embryonic fibroblasts (MEFs) were co-cultured with ECM slices to evaluate biocompatibility. The relative residual RNA and protein contents of ECM slices significantly decreased after decellularization. HE staining showed that SDS+Triton X-100 treatment better destroyed cellular structure and removed nuclei of ECM slices, compared with SDS treatment. Immunostaining showed that collagen IV and laminin were better preserved and presented better similarity to original cardiac tissue in ECM slices acquired by SDS+Triton X-100 treatment. However, collagen IV and laminin were significantly decreased and arranged disorderly in SDS treated group. We observed effective survival (≥ 12 days) of MEFs and mES-CMs on ECM slices acquired by SDS+Triton X-100 treatment, and signs of integration, whereas those signs were not found in SDS treated group. We concluded that, compared with traditional SDS method, new combined protocol (SDS+Triton X-100) generated ECM slices with better component and structural preservation, as well as better biocompatibility.


Assuntos
Matriz Extracelular/química , Ventrículos do Coração/citologia , Engenharia Tecidual/métodos , Alicerces Teciduais , Animais , Camundongos , Octoxinol , Dodecilsulfato de Sódio
13.
Photodiagnosis Photodyn Ther ; 45: 103911, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38043761

RESUMO

BACKGROUND: Comparison of OPD-Scan III and Pentacam measurements of relevant parameters guiding the selection of multifocal intraocular lenses in cataract patients. METHODS: A retrospective study included 120 patients (120 eyes) with cataract. Their chord kappa, chord alpha, corneal spherical aberration, and pupil size were measured by OPD-Scan Ⅲ and Pentacam. Pairwise t-tests, Pearson tests, and Bland-Altman analyses were used, respectively, to assess the difference, correlation, and agreement between the devices. RESULTS: There was no significant difference in photopic chord kappa and corneal spherical aberration between the two instruments (P = 0.054, P = 0.065). Chord alpha and pupil size varied significantly between the two instruments (P < 0.001). OPD-Scan III results revealed a significant association between photopic chord kappa and mesopic chord kappa (r = 0.823, P < 0.001). There was a significant positive correlation between photopic and mesopic chord kappa measured by OPD-Scan Ⅲ and chord kappa measured by Pentacam (r = 0.840, r  = 0.757, P < 0.001). The chord alpha evaluated by the two tools had a moderate correlation (r = 0.442, P < 0.001) between them. Bland-Altman analysis showed that there was excellent agreement between the two instruments in measuring chord kappa and corneal spherical aberration, while the chord alpha and pupil size were not consistent. CONCLUSIONS: The chord kappa and corneal spherical aberration measured by OPD-Scan III and Pentacam were consistent in the preoperative decision making of multifocal intraocular lens implantation in cataract patients, both of which have clinical guiding significance. In addition, OPD-Scan III provides more comprehensive day and night chord kappa and pupil diameters, which improves clinical advice for patients with complicated ocular diseases and high demands for nocturnal vision.


Assuntos
Catarata , Fotoquimioterapia , Humanos , Acuidade Visual , Estudos Retrospectivos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes , Biometria
14.
J Hazard Mater ; 473: 134637, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38772112

RESUMO

Highly selective removal of residual cephalosporin antibiotics from complex systems is crucial for human health and ecological environment protection. Herein, a newly molecularly imprinted polymer adsorbent (CPDs-NH2@MIP) with enhanced selectivity for ceftiofur sodium (CTFS) was developed by using the special carbonized polymer dots (CPDs-NH2) as functional monomer. The CPDs-NH2 has a nano-spherical structure and functionalized groups (CC, -NH2) via the incomplete carbonization polymerization of citric acid, acrylamide and ethylenediamine, which can accurately interact with CTFS by overcoming steric hindrance, resulting in more precisely imprinted sites and reducing non-imprinted regions in MIP. The presented CPDs-NH2@MIP exhibited excellent adsorption capacity for CTFS (68.62 mg g-1), achieving equilibrium within 10 min, and highly selectivity in mixed solution containing five coexisting substances, with an imprinted factor (5.61). Compared with commercial adsorbents and MIPs prepared with traditional chain functional monomers, the CPDs-NH2@MIP showed significant advantage in selective recognition and separation of target. Analysis of microstructure and mechanism proved that usage of the spherical functional monomer generated precise imprinting sites and dense structure in CPDs-NH2@MIP, which effectively enhanced the selectivity in complex system combined with hydrogen bonding interaction. The idea of designing and using spherical functional monomer will promote the practicality of molecularly imprinted polymer adsorbents.

15.
J Colloid Interface Sci ; 656: 332-345, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37995403

RESUMO

Molecularly imprinted polymers (MIPs) synthesized from chain functional monomers are restricted by spatial extension and exhibit relatively poor affinity and selectivity; this results in unsatisfactory applications in complex media. In this study, we prepared unique spherical carbonized polymer dots (CPDs-OH) via the incomplete carbonization of 1-allyl-3-vinylimidazolium bromide and ethylene glycol, and used it as a functional monomer to prepare a newly imprinted polymer (CPDs-OH@MIP) in aqueous media. As a result, the CPDs-OH@MIP exhibited effective recognition of oxytetracycline with an impressive imprinting factor of 6.17, surpassing MIPs prepared with chain functional monomers (1-3). Furthermore, CPDs-OH@MIP exhibited excellent adsorption for oxytetracycline (278.52 mg g-1) and achieved equilibrium in 30 min, with stronger resistance to coexisting cations, anions, and humic acid. Compared to other MIPs and adsorbents, the recognition performance of CPDs-OH@MIP improved 2-4 times; this polymer could remove >92.1% of oxytetracycline in real water samples with at least 10 cycle times. CPDs-OH@MIP prepared using the special spherical monomer forms a denser structure with fewer nonimprinted regions and precisely imprinted sites, remarkably improving the affinity and selectivity of MIPs combined via hydrogen bonds and electrostatic and π-π interactions. Our proposed strategy provides an effective basis for breakthroughs in the practical application of MIPs.

16.
Biochim Biophys Acta Mol Basis Dis ; 1870(4): 167125, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38508477

RESUMO

Scarring, a prevalent issue in clinical settings, is characterized by the excessive generation of extracellular matrix within the skin tissue. Among the numerous regulatory factors implicated in fibrosis across various organs, the apelin/APJ axis has emerged as a potential regulator of fibrosis. Given the shared attribute of heightened extracellular matrix production between organ fibrosis and scarring, we hypothesize that the apelin/APJ axis also plays a regulatory role in scar development. In this study, we examined the expression of apelin and APJ in scar tissue, normal skin, and fibroblasts derived from these tissues. We investigated the impact of the hypoxic microenvironment in scars on apelin/APJ expression to identify the transcription factors influencing apelin/APJ expression. Through overexpressing or knocking down apelin/APJ expression, we observed their effects on fibroblast secretion of extracellular matrix proteins. We further validated these effects in animal experiments while exploring the underlying mechanisms. Our findings demonstrated that the apelin/APJ axis is expressed in fibroblasts from keloid, hypertrophic scar, and normal skin. The regulation of apelin/APJ expression by the hypoxic environment in scars plays a significant role in hypertrophic scar and keloid development. This regulation promotes extracellular matrix secretion through upregulation of TGF-ß1 expression via the PI3K/Akt/CREB1 pathway.


Assuntos
Cicatriz Hipertrófica , Queloide , Animais , Apelina/genética , Apelina/metabolismo , Receptores de Apelina/genética , Receptores de Apelina/metabolismo , Fibrose , Queloide/metabolismo , Fosfatidilinositol 3-Quinases , Humanos
17.
World J Gastrointest Surg ; 16(2): 382-395, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38463377

RESUMO

BACKGROUND: The systemic inflammatory response index (SIRI) has been demonstrated to make a significant difference in assessing the prognosis of patients with different solid neoplasms. However, research is needed to ascertain the accuracy and reliability of applying the SIRI to patients who undergo robotic radical gastric cancer surgery. AIM: To validate the applicability of the SIRI in assessing the survival of gastric cancer patients and evaluate the clinical contribution of preoperative SIRI levels to predicting long-term tumor outcomes in patients, who received robotic radical gastric cancer surgery. METHODS: Initially, an exhaustive retrieval was performed in the PubMed, the Cochrane Library, EMBASE, Web of Science, and Scopus databases to identify relevant studies. Subsequently, a meta-analysis was executed on 6 cohort studies identifying the value of the SIRI in assessing the survival of gastric cancer patients. Additionally, the clinical data of 161 patients undergoing robotic radical gastric cancer surgery were retrospectively analyzed to evaluate their clinicopathological characteristics and relevant laboratory indicators. The association between preoperative SIRI levels and 5-year overall survival (OS) and disease-free survival (DFS) was assessed. RESULTS: The findings demonstrated an extensive connection between SIRI values and the outcome of patients with gastric cancer. Preoperative SIRI levels were identified as an independent hazard feature for both OS and DFS among those who received robotic surgery for gastric cancer. SIRI levels in gastric cancer patients were observed to be associated with the presence of comorbidities, T-stage, carcinoembryonic antigen levels, the development of early serious postoperative complications, and the rate of lymph node metastasis. CONCLUSION: SIRI values are correlated with adverse in the gastric cancer population and have the potential to be utilized in predicting long-term oncological survival in patients who undergo robotic radical gastric cancer surgery.

18.
Environ Sci Pollut Res Int ; 31(3): 4318-4329, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38100024

RESUMO

Mercury ion (Hg2+) is a highly toxic and ubiquitous pollutant, whose effective detection has aroused widespread concern. A novel ratiometric fluorescent sensor has been designed to rapidly and efficiently detect Hg2+ based on blue/red carbon dots (CDs) with environmental friendliness. This sensor was well characterized via TEM, FTIR, XPS, UV-vis, and zeta potential analysis and displayed excellent fluorescence properties and stability. The fluorescence of blue CDs at 447 nm was significantly quenched with the addition of Hg2+ resulted from the static quenching, whereas that of red CDs at 650 nm remained invariable. A sensitive method for Hg2+ determination was constructed in the range of 0.05-7.0 nmol mL-1 with optimal conditions, and the detection limit was down to 0.028 nmol mL-1. Meanwhile, compared to other 17 metal ions, the ratiometric fluorescent sensor exhibited high selectivity for Hg2+. Furthermore, satisfied recoveries had also been obtained for measuring trace Hg2+ in practical environmental samples. This developed ratiometric fluorescent sensor provided a reliable, environmental-friendly, rapid, and efficient platform for the detection of Hg2+ in environmental applications.


Assuntos
Mercúrio , Pontos Quânticos , Espectrometria de Fluorescência/métodos , Mercúrio/análise , Corantes Fluorescentes , Carbono , Íons , Limite de Detecção
19.
Fitoterapia ; 168: 105545, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37207791

RESUMO

Six new diterpenoids, identified as two abietane derivatives, euphraticanoids J and K (1 and 2), two pimarane derivatives, euphraticanoids L and M (3 and 4), and two 9,10-seco-abietane derivatives, euphraticanoids N and O (5 and 6) were isolated from Populus euphratica resins. Their structures including absolute configurations were characterized using spectroscopic, quantum chemical NMR, and ECD calculation methods. The anti-inflammatory activity of the compounds was tested and the results revealed that compounds 4 and 6 inhibited the production of iNOS and COX-2 in a dose-dependent manner in lipopolysaccharide (LPS)-induced RAW 264.7 cells.


Assuntos
Diterpenos , Populus , Abietanos/farmacologia , Estrutura Molecular , Diterpenos/farmacologia , Diterpenos/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Resinas Vegetais
20.
Fitoterapia ; 169: 105564, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37295754

RESUMO

Eight previously unknown 2-(2-phenylethyl)chromone derivatives, called aquichromones A - E (1-3, 5 and 6) and 8-epi-aquichromone C (4), including two pairs of enantiomers [(±)-1 and (±)-2] were isolated from the agarwood of Aquilaria sinensis. The structures and absolute stereochemistry of these natural products were elucidated by using spectroscopic and computational methods. The result of biological assay showed that two members of this group, 4 and 5, have significant dose-dependent anti-inflammatory activity.


Assuntos
Cromonas , Thymelaeaceae , Cromonas/farmacologia , Estrutura Molecular , Flavonoides/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Thymelaeaceae/química , Madeira/química
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