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1.
Mol Carcinog ; 63(6): 1013-1023, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38380955

RESUMO

Esophageal squamous cell carcinoma (ESCC) stands as a highly lethal malignancy characterized by pronounced recurrence and metastasis, resulting in a bleak 5-year survival rate. Despite extensive investigations, encompassing genome-wide association studies, the identification of robust prognostic markers has remained elusive. In this study, leveraging four independent data sets comprising 404 ESCC patients, we conducted a systematic analysis to unveil pivotal genes influencing overall survival. our meta-analysis identified 278 genes significantly associated with ESCC prognosis. Further exploration of the prognostic landscape involved an examination of expression quantitative trait loci for these genes, leading to the identification of six tag single nucleotide polymorphisms predictive of overall survival in a cohort of 904 ESCC patients. Notably, functional annotation spotlighted rs11227223, residing in the enhancer region of nuclear paraspeckle assembly transcript 1 (NEAT1), as a crucial variant likely exerting a substantive biological role. Through a series of biochemistry experiments, we conclusively demonstrated that the rs11227223-T allele, indicative of a poorer prognosis, augmented NEAT1 expression. Our results underscore the substantive role of NEAT1 and its regulatory variant in prognostic predictions for ESCC. This comprehensive analysis not only advances our comprehension of ESCC prognosis but also unveils a potential avenue for targeted interventions, offering promise for enhanced clinical outcomes.


Assuntos
Biomarcadores Tumorais , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Polimorfismo de Nucleotídeo Único , Humanos , Prognóstico , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/mortalidade , Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , RNA Longo não Codificante/genética , Feminino , Masculino
2.
Analyst ; 149(5): 1537-1547, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38284466

RESUMO

The development of innovative methods for real-time surveillance of enzymatic activity determination processes is essential, particularly for insoluble substrate enzymatic assessments. In this work, a novel method for enzymatic activity determination was devised by assembling a 190 nm silica colloidal crystal (SCC) film onto a glass slide, coupled with Ordered Porous Layer Interferometry (OPLI) technology. By fixing the substrate of the enzyme on the surface of the silica sphere, a solid-liquid interface can be formed for monitoring enzymatic activity. The enzymatic activity is gauged by the change in the SCC film's thickness caused by the digestion of the loaded substrate. The procedure of chymotrypsin-mediated casein digestion was documented in real time, facilitating the examination of chymotrypsin's activity and kinetics. The newly-developed enzymatic activity determination method demonstrated exceptional sensitivity towards chymotrypsin activity, with a linear range spanning 0.0505-2.02 units per mg. Additionally, the method was extended to the assessment of fibrinolysis enzyme activity and kinetic analysis, yielding promising results. Therefore, this technique can serve as a real-time, user-friendly, cost-effective novel approach for enzymatic activity determination, providing fresh perspectives for enzymatic activity determination studies.


Assuntos
Quimotripsina , Fibrinolíticos , Fibrinolíticos/farmacologia , Cinética , Porosidade , Interferometria , Dióxido de Silício/química
3.
Int J Cosmet Sci ; 46(3): 424-436, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38229406

RESUMO

BACKGROUND: Alterations in the secretion and composition of skin surface lipids (SSL) are closely associated with the development of acne. Lipidomics is a useful tool to analyse the SSL of different types of acne. Our previous study found that phosphatidylserine and triacylglycerols dominate SSL changes in male acne and infantile acne, respectively. However, skin surface lipids as well as specific lipids in female acne patients remain to be investigated. OBJECTIVES: To analyse and compare the SSL profile of acne women and healthy women and to discuss the involvement of differential lipids in acne development. METHODS: Systematic lipidomics approach (high-throughput UPLC-QTOF-MS technology in combination with multivariate data analysis methods) was used to analyse the variations of SSL between acne and healthy groups. RESULTS: Analysis revealed significant differences in lipid content and composition between the two groups. Further analysis showed that levels of 13 individual lipids were significantly different and followed the same trend as the main class and subclasses. The largest individual contributor to the subgroup was triglycerides (TG) and phosphatidylinositol (PI). In addition, female acne patients exhibited reduced ceramide chain length (CCL) and increased levels of unsaturated fatty acids (UFAs), The changes of CCL in female acne are identical to male acne. CONCLUSIONS: There was a significantly higher level of TG and PI in the SSL of female acne patients. A reduction in CCL and an increase in UFAs content might contribute to the reduced skin barrier function in acne patients. The results suggest that female acne may have different pathogenesis than male acne.


Assuntos
Acne Vulgar , Face , Lipidômica , Lipídeos , Pele , Humanos , Acne Vulgar/metabolismo , Feminino , Lipidômica/métodos , Lipídeos/análise , Pele/metabolismo , Pele/química , Adulto Jovem , Adulto , Adolescente
4.
Anim Cogn ; 26(3): 963-972, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36683113

RESUMO

The ultrasonic vocalizations (USVs) of rodents play a substantial role in the communication and interaction between individuals; exhibit a high degree of complexity; and are influenced by a multitude of developmental, environmental, and phylogenetic factors. The functions of USVs are mainly studied in laboratory mice or rats. However, the behavioral relevance of USVs in wild rodents is poorly studied. In this work, we systematically investigated the vocal repertoire of the wild mouse Mus caroli and wild rat Rattus losea in multiple social or non-social contexts, e.g., pup-isolation, juvenile-play, paired opposite-sex encounter, female-female interaction, social-exploring, or foot-shock treatment. Unlike the laboratory mice, M. caroli, whose USVs were recorded during pup-isolation and courtship behaviors, did not produce any vocal sounds during juvenile-play and female-female interactions. R. losea, similar to laboratory rats, emitted USVs in all test situations. We found higher peak frequencies of USVs in both these two wild rodent species than in laboratory animals. Moreover, the parameters and structures of USVs varied significantly across different social or non-social contexts even within each species, confirming the context-sensitivity and complexity of vocal signals in rodents. We also noted a striking difference in call types between these two species: no downward type occurred in M. caroli, but no upward type occurred in R. losea, thereby highlighting the interspecific difference of vocal signals among rodents. Thus, the present study presents behavioral foundations of the vocalization context in wild mice and wild rats, and contributes to revealing the behavioral significance of widely used USVs in rodents.


Assuntos
Roedores , Vocalização Animal , Camundongos , Feminino , Ratos , Animais , Filogenia , Ultrassom , Comportamento Social
5.
Virus Genes ; 59(4): 604-612, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37266848

RESUMO

H11N9 viruses in wild birds might have provided the NA gene of human H7N9 virus in early 2013 in China, which evolved with highly pathogenic strains in 2017 and caused severe fatalities. To investigate the prevalence and evolution of the H11N9 influenza viruses, 16,781 samples were collected and analyzed during 2016-2020. As a result, a novel strain of influenza A (H11N9) virus with several characteristics that increase virulence was isolated. This strain had reduced pathogenicity in chicken and mice and was able to replicate in mice without prior adaptation. Phylogenetic analyses showed that it was a sextuple-reassortant virus of H11N9, H3N8, H3N6, H7N9, H9N2, and H6N8 viruses present in China, similar to the H11N9 strains in Japan and Korea during the same period. This was the H11N9 strain isolated from China most recently, which add a record to viruses in wild birds. This study identified a new H11N9 reassortant in a wild bird with key mutation contributing to virulence. Therefore, comprehensive surveillance and enhanced biosecurity precautions are particularly important for the prediction and prevention of potential pandemics resulting from reassortant viruses with continuous evolution and expanding geographic distributions.


Assuntos
Vírus da Influenza A Subtipo H3N8 , Subtipo H7N9 do Vírus da Influenza A , Vírus da Influenza A Subtipo H9N2 , Influenza Aviária , Animais , Camundongos , Humanos , Patos , Subtipo H7N9 do Vírus da Influenza A/genética , Vírus da Influenza A Subtipo H9N2/genética , Filogenia , Animais Selvagens , Galinhas , Vírus Reordenados/genética
6.
Ecotoxicol Environ Saf ; 252: 114588, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36724711

RESUMO

Gold nanochains (AuNCs) were prepared, and this novel material was combined with carboxylated multi-walled carbon nanotubes (cMWCNTs) to be a nanocomposite for the first time. The transmission electron microscopy (TEM), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and UV-Vis spectra were used to characterize the successful preparation of AuNCs and AuNC-cMWCNT composite. Based on this hybrid material, a voltammetric sensor of bisphenol A (BPA) was established. The proposed sensor displayed excellent performance for the measurement of BPA by obvious decreased anodic peak potential and enlarged peak current. Using the optimized conditions, BPA was detected using linear sweep voltammetry, and the linear range showed as wide as 0.5 µM to 2000 µM with the detection limit estimated to be 12 nM (S/N = 3). The as-proposed sensor also exhibited satisfactory performance in determining BPA of actual plastic samples.


Assuntos
Nanotubos de Carbono , Nanotubos de Carbono/química , Ouro/química , Técnicas Eletroquímicas/métodos , Fenóis/química , Eletrodos
7.
Chemistry ; 28(2): e202103795, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34791739

RESUMO

Transcatheter arterial embolization (TAE) is wildly used in clinical treatments. However, the online monitoring of the thrombosis formation is limited due to the challenges of the direct visualization of embolic agents and the real-time monitoring of dynamic blood flow. Thus, we developed a photochemical afterglow implant with strong afterglow intensity and a long lifetime for embolization and imaging. The liquid pre-implant injected into the abdominal aorta of mice was rapidly transformed into a hydrogel in situ to embolize the blood vessel. The vascular embolism position can be observed by the enhanced afterglow of the fixed implant, and the long lifetime of afterglow can also be used to monitor the effect of embolization. This provides an excellent candidate in bio-imaging to avoid the autofluorescence interference from continuous light excitation. The study suggests the potential usefulness of the implant as an embolic agent in TAE and artery imaging during a surgical procedure.


Assuntos
Embolização Terapêutica , Animais , Artérias/diagnóstico por imagem , Diagnóstico por Imagem , Hidrogéis , Camundongos
8.
Ecotoxicol Environ Saf ; 237: 113503, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35453019

RESUMO

Paraquat (PQ) is a ubiquitously applied herbicide. Long-term PQ exposure with low dose has been reported to induce abnormal expression of long non-coding RNAs (lncRNAs) in brain nerve cells, which could further lead to Parkinson's disease (PD). N6-methyladenosine (m6A) modification has recently been identified as having an important role in regulating the function of lncRNAs. However, how m6A modification regulates lncRNAs following PQ exposure remains largely unknown. Herein, this study reported m6A modification of lncRNAs in mouse neuroblastoma cells (Neuro-2a) following PQ induced reactive oxide species (ROS). M6A sequencing was performed to explore the m6A modificated pattern of lncRNAs in Neuro-2a cells which were treated with 200 µM PQ for 3 h. It was found that PQ hypermethylated total RNA and changed the expression of m6A methyltransferase and demethylase proteins, which leading to the alteration of m6A modification of lncRNAs. Furthermore, the functional analysis further revealed that N-acetyl-L-cysteine (NAC),a ROS scavengers, partly reversed PQ-induced distinct m6A modificated pattern of lncRNAs. In addition, tow specific m6A modified lncRNAs were identified: cell division cycle 5-like (lncRNA CDC5L) and signal transducer and activator of transcription 3 (lncRNA STAT3), which could influence downstream autophagy related biological function. In summary, this work could potentially contribute to the new insight of lncRNAs m6A modification mechanism in the field of environmental toxicology.


Assuntos
Paraquat , RNA Longo não Codificante , Adenosina/análogos & derivados , Adenosina/metabolismo , Animais , Camundongos , Estresse Oxidativo/genética , Paraquat/toxicidade , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Espécies Reativas de Oxigênio/metabolismo
9.
Anal Chem ; 92(17): 12071-12078, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32786477

RESUMO

An approach to optical transduction and amplification of amphiphile-triggered orientational responses of liquid crystals (LCs) based on the interference effect was developed. The sensitive substrate was obtained by lading 4'-pentyl-4-cyanobiphenyl (5CB) into three-dimensionally ordered silica colloidal crystal (SCC) films. Changes in the optical thickness (ΔOT) of the substrates, which are inverted by their Fabry-Perot fringes, depend on the changes of the refractive index caused by the differences in the orientations of LCs. The orientation changes of LCs loading into SCC films have the effect of amplifying signals. These are based on the interactions between surfactants (alkyl trimethylammonium halides (CnTABs, n = 8, 10, 12, 14, and 16) and sodium lauryl sulfonate (SLS)) and LCs, which induce a particular orientation of the LCs molecules. In this flowing system, the reversibility of the signal response for the adsorption of amphiphile was related to the length of the surfactant chain and its critical micelle concentration (CMC). A new method capable of real-time sensing adsorbate-triggered anchoring transitions based on LC-infiltrated SCC films was accomplished. These results provide basics and principles for online, label-free, and real-time analysis of molecules and their interactions in a flowing environment based on the interference effect.

10.
Inorg Chem ; 59(7): 4406-4413, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32154724

RESUMO

We have recently reported a strongly luminescent osmium(VI) nitrido complex [OsVI(N)(NO2-L)(CN)3]- [HNO2-L = 2-(2-hydroxy-5-nitrophenyl)benzoxazole]. The excited state of this complex readily activates the strong C-H bonds of alkanes and arenes (Commun. Chem. 2019, 2, 40). In this work, we attempted to tune the excited-state properties of this complex by introducing various substituents on the bidentate L ligand. The series of nitrido complexes were characterized by IR, UV/vis, 1H NMR, and electrospray ionization mass spectrometry. The molecular structures of five of the nitrido compounds have been determined by X-ray crystallography. The photophysical and electrochemical properties of these complexes have been investigated. The luminescence of these nitrido complexes in the solid state, in a CH2Cl2 solution, and in a CH2Cl2 solid matrix at 77 K glassy medium clearly shows that these emissions are due to 3LML'CT [L ligand to Os≡N] phosphorescence. The presence of strongly electron-withdrawing substituents in these complexes enhances the LML'CT emission. Our result demonstrates that the excited-state properties of this novel class of luminescent osmium(VI) nitrido complexes can be fine-tuned by introducing various substituents on the bidentate L ligand.

11.
Anal Chem ; 91(9): 6080-6087, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30994327

RESUMO

With the aim to develop better and more reliable interference effective substrates, silica colloidal crystal films with different sphere diameters and film thicknesses were successfully made by an improved vertical deposition method and a systematic investigation of their reflectometric interference spectroscopy (RIfS) properties are presented in this work. The influence of silica sphere diameter and film thickness on the RIfS signals was studied. The results showed that the film thickness is the key factor of RIfS signals. An RIfS system was set up by using a silica colloidal crystal film as an interference effective substrate. The influence of film thickness on the response to refractive index changes of the proposed system was also investigated. When the influence of film thickness on RIfS signals and refractive index response we considered together, silica colloidal crystal films with a thickness between 4 and 6 µm were chosen for sensor construction. Monitoring the digestive process of gelatin with trypsin was also demonstrated by combining gelatin-modified silica colloidal crystal films with RIfS. The system showed excellent sensitivity with a wide linear range and could achieve real-time measurement of each process. It has been proved that this is a promising method to construct biosensors using silica colloidal crystal films as interference-sensitive substrates.


Assuntos
Técnicas Biossensoriais , Gelatina/análise , Dióxido de Silício/química , Coloides/química , Cristalização , Gelatina/metabolismo , Tamanho da Partícula , Análise Espectral , Propriedades de Superfície , Tripsina/metabolismo
12.
Small ; 15(38): e1901687, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31348602

RESUMO

The size effect on the cellular uptake of nanoparticles (NPs) has been extensively studied, but it is still not well understood. Herein, a reductionist approach is used to minimize all influencing factors except the particle size, and co-exposure of different-sized silica nanoparticles (SNPs) is adopted instead of the common single exposure. SNPs are found being internalized by Hela cells in serum-free medium mainly via clathrin-dependent endocytosis, thus simplifying the data analysis for reliable attribution to size effects. Remarkably, even though at conditions that the size effects seem very small or even undetectable in the common single exposure experiments, the co-exposure experiments reveal significant size effects due to an unexpected interplay between two different-sized SNPs. Namely, the bigger SNPs significantly promote the cellular uptake of the smaller ones, while the smaller SNPs inhibit the internalization of the bigger ones, with a total uptake increase of the particle number of SNPs in the cells. This strong interplay between different-sized NPs might unavoidably exist within most "single-sized" NP products, whose sizes actually distribute in certain ranges, thus urging reconsideration of the size effect on the cellular uptake of NPs, for the benefits of both bioapplications and safety assessment of nanomaterials.


Assuntos
Nanopartículas/química , Nanopartículas/metabolismo , Dióxido de Silício/química , Células HeLa , Humanos
13.
Pestic Biochem Physiol ; 160: 181-186, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31519253

RESUMO

Fertility control is considered as the second-generation pest rodent management strategy. Most previous studies have focused on the dosage-dependent effects of quinestrol and levonorgestrel compounds (EP-1) at a ratio of 1:2, but the ratio-dependent effects of EP-1 have not been fully investigated, especially in male rodents. To test the ratio-dependent antifertility effects of EP-1 with different ratios (1:2, 1:1, and 2:1) on male Swiss outbred strain of laboratory mice, forty male mice were randomly assigned into four groups (n = 10). Mice in the three treatment groups were provided one of the three EP-1 mixture compounds for 3 successive days via gavage at a dosage of 50 mg/kg(body weight), and then all mice were sacrificed 15 days after the gavage treatment. Reproductive organ weights, sperm density and motility, levels of testosterone (T), estradiol (E2), luteinizing hormone (LH), and follicle stimulating hormone (FSH) in serum and/or testis, and androgen receptor (AR), estrogen receptor α (ERα), estrogen receptor ß (ERß), luteinizing hormone receptor (LHR), and aromatase in testis were determined. Each of the ratios of quinestrol and levonorgestrel significantly decreased the density and motility of sperm and induced atrophy of the epididymis and seminal vesicle. The combination of compounds also significantly reduced serum T and LH levels, increased testicular T levels and decreased testicular estradiol ERß and aromatase levels. EP-1 delivered at a ratio of 1:1 induced the most significant effects on the reproductive parameters assessed and shows the potential for use in fertility control of male rodents.


Assuntos
Estrogênios/farmacologia , Levanogestrel/farmacologia , Quinestrol/farmacologia , Reprodução/efeitos dos fármacos , Animais , Aromatase/metabolismo , Hormônios Esteroides Gonadais/sangue , Masculino , Camundongos , Tamanho do Órgão/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/enzimologia , Testículo/metabolismo
14.
Biochem Biophys Res Commun ; 503(3): 1949-1954, 2018 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-30072098

RESUMO

Glaucocalyxin A (GLA) is a natural ent-Kaurane diterpenoid that possesses cardioprotective effect. Recently, it has been reported that GLA inhibits liver and pulmonary fibrosis, whereas its role in cardiac fibrosis remains unknown. In the present study, we evaluated the effect of GLA on the pathogenesis of cardiac fibrosis in vitro. The results showed that GLA inhibited angiotensin II (Ang II)-induced proliferation and migration in cardiac fibroblasts (CFs). GLA reduced the expression of alpha-smooth muscle actin (α-SMA) in Ang II-induced CFs, suggesting that GLA prevented the differentiation of CFs to myofibroblasts. Furthermore, the production of extracellular matrix (ECM) components including type I collagen (Col-I) and fibronectin, as well as the matrix metalloproteinases (MMPs) including MMP-2 and MMP-9 were reduced by GLA in Ang II-induced CFs. In addition, GLA prevented the Ang II-induced activation of transforming growth factor beta 1 (TGF-ß1)/Smad3 pathway in CFs. Collectively, our results demonstrated that GLA acted as an anti-fibrotic agent in cardiac fibrosis, which might be mediated by the regulation of TGF-ß1/Smad3 pathway. GLA might be an attractive candidate for improving the prognosis of acute myocardial infarction (AMI) by controlling the cardiac fibrosis.


Assuntos
Angiotensina II , Diterpenos do Tipo Caurano/farmacologia , Fibrose/induzido quimicamente , Fibrose/tratamento farmacológico , Miofibroblastos/efeitos dos fármacos , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Ratos , Ratos Sprague-Dawley
15.
Acc Chem Res ; 50(1): 32-40, 2017 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-27983801

RESUMO

Resonance energy transfer (RET) describes the process that energy is transferred from an excited donor to an acceptor molecule, leading to a reduction in the fluorescence emission intensity of the donor and an increase in that of the acceptor. By this technique, measurements with the good sensitivity can be made about distance within 1 to 10 nm under physiological conditions. For this reason, the RET technique has been widely used in polymer science, biochemistry, and structural biology. Recently, a number of RET systems incorporated with nanoparticles, such as quantum dots, gold nanoparticles, and upconversion nanoparticles, have been developed. These nanocrystals retain their optical superiority and can act as either a donor or a quencher, thereby enhancing the performance of RET systems and providing more opportunities in excitation wavelength selection. Notably, lanthanide-doped upconversion nanophosphors (UCNPs) have attracted considerable attention due to their inherent advantages of large anti-Stoke shifts, long luminescence lifetimes, and absence of autofluorescence under low energy near-infrared (NIR) light excitation. These nanoparticles are promising for the biodetection of various types of analytes. Undoubtedly, the developments of those applications usually rely on resonance energy transfer, which could be regarded as a flexible technology to mediate energy transfer from upconversion phosphor to acceptor for the design of luminescent functional nanoplatforms. Currently, researchers have developed many RET-based upconversion nanosystems (RET-UCNP) that respond to specific changes in the biological environments. Specifically, small organic molecules, biological molecules, metal-organic complexes, or inorganic nanoparticles were carefully selected and bound to the surface of upconversion nanoparticles for the preparation of RET-UCNP nanosystems. Benefiting from the advantage and versatility offered by this technology, the research of RET-based upconversion nanomaterials should have significant implications for advanced biomedical applications. It should be noted that energy transfer in a UCNP based nanosystem is most often related to resonance energy transfer but that reabsorption (and maybe other energy transfer processes) may also play an important role and that more studies regarding the fundamental aspects for energy transfer with UCNPs is necessary. In this Account, we present an overview of recent advances in RET-based upconversion nanocomposites for biodetection with a particular focus on our own work. We have designed a series of upconversion nanoplatforms with remarkably high versatility for different applications. The experience gained from our strategic design and experimental investigations will allow for the construction of next-generation luminescent nanoplatform with marked improvements in their performance. The key aspects of this Account include fundamental principles, design and preparation strategies, biodetection in vitro and in vivo, future opportunities, and challenges of RET-UCNP nanosystems.


Assuntos
Transferência de Energia , Nanoestruturas , Raios Infravermelhos
16.
J Nanosci Nanotechnol ; 18(12): 8367-8375, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30189961

RESUMO

Ordered silica nanosphere templates, which are usually known as colloidal crystals, are most widely used to prepare ordered porous nanostructure materials among the templates to fabricate nanostructure materials. We present here a method for the simultaneous assembly of multiple ordered silica nanosphere templates with same quality, in which a glass trough together with a stand was used as the experimental cell. Two different diameters of silica colloidal particles were selected for our experiments, namely ∼190 nm and ∼280 nm. The growth process, thickness and optical properties of films of silica nanospheres on substrates were studied. The particle sedimentation and solvent evaporation both play a role in determining particle volume fractions. In addition, the standard deviation of the diameter of the particles affects the optical properties of the films along the growth direction. There was almost no difference observed in our measurements of the film thickness and optical properties for both the same regions of different films and different regions of the same film along the direction perpendicular to the growth direction. The elucidation of the growth process and characterization of the film properties achieved in this study could help us to obtain better quality templates. This is the first systematic study of the evolution of the thickness and optical properties of ordered silica nanosphere films formed by a simultaneous assembly process.

17.
J Nanosci Nanotechnol ; 18(10): 6850-6858, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29954502

RESUMO

The growing demand of metal sulfides using in various applications has in turn greatly stimulated basic research to develop novel nanomaterials with controlled size, shape, phase and desired properties. Specifically, ultrathin ZnS nanowires with diameter of less than 2 nm have attracted significant interest because of their considerable promise in sensors, phosphor host materials, photodetectors, and other devices. A novel method for the synthesis of controlled morphology, phase and size of ZnS nanocrystals has been developed. Especially, ultrathin ZnS nanowires with 1.5 nm in diameter were synthesized from single-source precursor zinc dicarbazoledithiocarbamate using oleylamine as capping ligand and solvent. Strong quantum confinement effects related to the unique nature of these ultrathin ZnS nanowires were observed. More importantly, we have presented the evidence for the assembly of ultra-small ZnS nanoparticles in 1-D polymer-like structures achieved by oriented attachment mechanism for synthesis of ultrathin ZnS nanowires.

18.
Chem Soc Rev ; 46(4): 1025-1039, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-27966684

RESUMO

Anti-Stokes shift luminescence is a special optical process, which converts long-wavelength excitation to short-wavelength emission. This unique ability is especially helpful for bio-applications, because the longer-wavelength light source, usually referring to near infrared light, has a larger penetration depth offering a longer working distance for in vivo applications. The anti-Stokes shift luminescence signal can also be distinguished from the auto-fluorescence of biological tissues, thus reducing background interference during bioimaging. Herein, we summarize recent advances in anti-Stokes shift luminescent materials, including lanthanide and triplet-triplet-annihilation-based upconversion nanomaterials, and newly improved hot-band absorption-based luminescent materials. We focus on the synthetic strategies, optical optimization and biological applications as well as present comparative discussions on the luminescence mechanisms and characteristics of these three types of luminescent materials.


Assuntos
Elementos da Série dos Lantanídeos/química , Nanoestruturas/química , Imagem Óptica/métodos , Fotoquimioterapia/métodos , Animais , Linhagem Celular Tumoral , Complexos de Coordenação/química , Humanos , Raios Infravermelhos , Luminescência , Microscopia de Fluorescência por Excitação Multifotônica , Neoplasias/diagnóstico , Neoplasias/terapia , Fenômenos Físicos
19.
Pestic Biochem Physiol ; 143: 122-126, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29183580

RESUMO

The aim of this study was to assess the effects and reversibility of the synthetic estrogen compound, quinestrol, on the reproductive organs, steroid hormones, and drug-metabolizing enzymes CYP3A4 and CYP1A2 in liver and kidney over time after two quinestrol treatments in female Mongolian gerbils (Meriones unguiculatus). Female gerbils were treated with 4mg/kg quinestrol (9 gerbils/group, 3 treated group) (1 control group, 0mg/kg) for 3days and treated again after 25days. Animals were killed for collection of samples at 5, 10 and 15days after the second treatment ending. Two interval quinestrol treatments significantly increased uterine weight, with trend of increase over time, but no change could be detected in ovarian weights. Quinestrol treatment increased progesterone and estradiol levels, both with trend of decline over time. Quinestrol increased liver and kidney weights and total enzyme content of CYP3A4 and CYP1A2, with trend of decline over time. On the basis of reversible changes of detoxification enzymes or organs, interval quinestrol treatment effectively and reversibly influenced the reproductive hormone and organ to some extent.


Assuntos
Estrogênios/farmacologia , Quinestrol/farmacologia , Animais , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP3A/metabolismo , Estradiol/sangue , Feminino , Gerbillinae/sangue , Gerbillinae/metabolismo , Rim/efeitos dos fármacos , Rim/enzimologia , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/patologia , Tamanho do Órgão/efeitos dos fármacos , Ovário/anatomia & histologia , Ovário/efeitos dos fármacos , Progesterona/sangue , Útero/efeitos dos fármacos , Útero/patologia
20.
J Acoust Soc Am ; 142(1): 29, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28764448

RESUMO

To reduce errors in species recognition and the probability of interbreeding that lowers fitness, individuals within sympatric zones shift the signals to differentiate from those of other species. In the present study, the differences of the acoustic features of ultrasounds (courtship calls during heterosexual encounters) and audible calls (distress calls during tail-clamp stress) are compared among three sympatric Rattus species (Rattus andamanensis, R. norvegicus, and R. losea). Results showed that the three species have significantly different call parameters, including call duration, peak frequency, bandwidth, pitch, goodness of pitch, frequency modulation, and Wiener entropy. This study provides quantitative evidence for character displacement in the acoustic signals of closely related sympatric Rattus species. Results indicate that the divergence of acoustic signal has arrived at the quite meticulous degree of evolution. Therefore, the acoustic signal trait is likely involved in the evolution of species diversity in rodents.

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