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1.
J Affect Disord ; 260: 557-568, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31539693

RESUMO

OBJECTIVE: This study mapped the topological configuration of the default mode network (DMN) in patients with depressive symptoms after acute ischemic stroke. METHODS: The study sample comprised 63 patients: 36 with poststroke depressive symptoms (PSD) and 37 without PSD matched according to age, gender and the severity of stroke. PSD was defined by a cutoff of ≥ 7 on the 15-item Geriatric Depression Scale (GDS). Resting-state functional magnetic resonance imaging (fMRI) was used to examine functional connectivity (FC) to reconstruct the DMN. Network based statistics estimated the FC differences of the DMN between the PSD and non-PSD groups. Graph theoretical approaches were used to characterize the topological properties of this network. RESULTS: The study sample mainly comprised patients with mild to moderate stroke. A widespread hyper-connected configuration of the functional DMN was characterized in PSD group. The orbital frontal, dorsolateral prefrontal, dorsal medial prefrontal and, ventromedial prefrontal corticis, the middle temporal gyrus and the inferior parietal lobule were the functional hubs related to PSD. The nodal topology in inferior parietal lobule and superior frontal gyrus, overlapping with dorsal medial prefrontal and, ventromedial prefrontal cortices, tended to be functionally integrated in patients with PSD. After False Discovery Rate correction, no significant difference between the PSD and non-PSD groups was found with respect to the global and nodal metrics of the DMN. However, the correlations between these altered network metrics and severity of PSD were lacking. LIMITATIONS: The diagnosis of PSD was based on the GDS score rather than established with a structured clinical interview. CONCLUSIONS: The DMN in PSD was functionally integrated and more specialized in some core hubs such as the inferior parietal lobule and dorsal prefrontal cortex. The configuration of the subnetwork like DMN may be more essential in the pathogenesis of PSD than single stroke lesions.

2.
J Cell Biochem ; 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31674056

RESUMO

Recently, microRNAs (miRNAs) receive more attention due to their role in the pathogenesis of malignancies. Retinoblastoma (RB) is the most serious and harmful malignant tumor in infants and young children with eye diseases, which often endangers the lives of children. This study was designed to determine how miR-598 is involved in RB progression. In this study, quantitative reverse transcription-polymerase chain reaction, Western blot, dual-luciferase reporter, Cell Counting Kit-8, and Transwell assays were adopted to detect miR-598 expression and function in RB. The decreased expression of miR-598 was identified in RB. Overexpression of miR-598 suppressed the viability and metastasis of RB cells. Further, E2F transcription factor 1 (E2F1) is verified as a direct target of miR-598. Furthermore, E2F1 recovered miR-598-mediated-inhibition of cell viability and metastasis in RB. In addition, miR-598 was found to promote cell apoptosis and inactivate the protein kinase B (AKT) pathway in RB. miR-598 suppressed RB cell viability and metastasis through inhibiting E2F1 and inactivating AKT pathway, which may provide a new perspective for RB treatment.

3.
J Hazard Mater ; : 121402, 2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31668761

RESUMO

Crystal facets engineering and graphene hybridizing have been proved to be effective means to improve the photocatalytic activities of semiconductor photocatalysts in recent years. However, most of these efforts are concentrated in metal oxides. In the present study, crystal facets effect on the photocatalytic activity of metal sulfide NiS2 was studied for the first time. It was found that the {111}-faceted NiS2 nanocrystals showed improved photocatalytic activity in the degradation of various typical pollutants in water compared with {100}-faceted NiS2 nanocrystals. Moreover, through hybridizing with rGO nanosheets, the photocatalytic activity of the {111}-faceted NiS2 nanocrystals can be further improved, resulting in the complete degradation of heavy metal hexavalent chromium and organic dyes. The photocatalytic mechanism was studied in detail through theory calculation and experimental characterization. It was found that both the surface energies of Ni-terminated and S-terminated {111} facets were much higher than that of {100} facets, indicating that {111} facets were more active. Besides, rGO hybridizing can realize the effective separation of photogenerated electrons and holes. The results provide important guidance for the further development of efficient metal sulfide photocatalysts.

4.
J Coll Physicians Surg Pak ; 29(10): 937-941, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31564265

RESUMO

OBJECTIVE: To determine the frequency of liver steatosis in chronic hepatitis B (CHB) patients measured by controlled attenuation parameter (CAP) and to describe the distribution of fibrosis and inflammation in different steatosis grading. STUDY DESIGN: Cross-sectional study. PLACE AND DURATION OF STUDY: Department of Infectious Diseases and Hepatology, The Second Hospital of Shandong University, Jinan, China, from January 2017 to December 2018. METHODOLOGY: CHB patients who were evaluated with transient elastography (TE) for liver fibrosis and steatosis were included. Liver biochemical testing was performed within 3 days of TE measurements. Steatosis grading was assessed as S0 (no steatosis, CAP 0-247 dB/m), S1 (mild steatosis, CAP 248-267 dB/m), S2 (moderate steatosis, CAP 268-279 dB/m) and S3 (severe steatosis, CAP >=280 dB/m). Statistically comparisons of continuous variables or percentages were performed. RESULTS: A total of 1,621 CHB patients were included. The frequencies of liver steatosis in CHB patients were 35.4% (574 patients), of which 314 patients (19.3%) were diagnosed as severe steatosis (grading S3). Comparisons of age, gender and liver fibrosis in different steatosis grading revealed no statistical differences (p=0.109, 0.075 and 0.269, respectively). However, ALT values in patients with severe steatosis (grading S3) were higher than those patients with steatosis grading S0 (p<0.001) and S2 (p=0.047). CONCLUSION: Steatosis is common in CHB patients. Liver fibrosis seemed not discrepant in different steatosis grading. More obvious hepatic inflammation is seen in CHB patients with severe steatosis.

6.
Diagn Pathol ; 14(1): 112, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31627758

RESUMO

BACKGROUND: Translocation-associated renal cell carcinoma involving ALK (ALK-tRCC) is a rare subtype of adult renal cell carcinoma (RCC) reported in recent years. It was recognized as a group of emerging /provisional RCC in the latest World Health Organization's classification (2016). CASE PRESENTATION: A new Chinese case of ALK-tRCC was reported. The patient was a 58-year-old man with a tumor in kidney. The tumor was composed of sheets of large cells with abundant eosinophilic cytoplasm and indistinct cell borders but conspicuous intracytoplasmic vacuoles. The nuclei were enlarged with a nucleolar of grade 4. Immunohistochemically, tumor cells were diffusely positive for PAX8, keratin (AE1/AE3), epithelial membrane antigen (EMA) and CK7. Fluorescent in situ hybridization (FISH) showed a rearrangement of ALK in tumor cells. CONCLUSION: ALK-tRCC is a rare subtype of adult RCC. Its diagnosis is very difficult because the histological spectrum is very wide. We suggested that RCCs should be screened for ALK expression by immunohistochemistry (IHC) for the patient might benefit from ALK inhibitors therapy.

7.
Se Pu ; 37(11): 1179-1184, 2019 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-31642270

RESUMO

A simple method based on direct injection-ultra performance liquid chromatography-triple quadrupole tandem mass spectrometry (UPLC-MS/MS) was established for the rapid determination of glyphosate, aminomethyl phosphonic acid, glufosinate, and ethephon residues in environmental water. The water samples were filtered through a 0.22-µm filter membrane or frozen and centrifuged to remove impurities, and then, the filtrate was directly subjected to quantitative analysis without derivatization. The analytes were separated on a Metrosep A Supp 5 column (150 mm×4.0 mm, 5 µm), and gradient elution was carried out using an ammonium bicarbonate-ammonia solution as the mobile phase. The data were collected by positive electrospray ionization in the multiple reaction monitoring (MRM) mode. The results showed that the correlation coefficients (r) of the linear calibration curves were greater than 0.999 in the corresponding linear ranges (0.50-50.0 µg/L). The detection limits of the analytes were 0.05-0.09 µg/L. The recoveries of glyphosate, aminomethyl phosphonic acid, glufosinate, and ethephon were in the ranges 76.3%-108%, 83.0%-107%, and 87.0%-105% at low, medium, and high spiked levels, respectively. The corresponding relative standard deviations were in the ranges 2.0%-12.3%, 2.4%-5.6%, and 2.7%-6.8%. Using this method, 34 water samples collected from Hainan Province were analyzed, among which 30 drinking water sources were found to be free from the four pesticides. Glyphosate and aminomethyl phosphonic acid were detected in three water samples near a betel nut orchard, while glufosinate and aminomethyl phosphonic acid were detected in a water sample near a banana orchard. This method is advantageous over the traditional derivatization method because of its simple operation, good reproducibility, and high accuracy; furthermore, the matrix interference effect is absent. Thus, this method is suitable for analyzing glyphosate, aminomethyl phosphonic acid, glufosinate, and ethephon residues in environmental water samples.

8.
Int J Biol Markers ; 34(3): 318-321, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31507249

RESUMO

OBJECTIVE: The aim of this study is to investigate the effect of colchicine and other medications for gout treatment on serum CA72-4 and other tumor markers including alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), CA19-9, CYFRA21-1, neuron specific enolase (NSE), prostate-specific antigen (PSA). METHODS: A total of 143 gout patients and 40 healthy individuals were randomly recruited. Of these patients, 38 did not receive any treatment; 42 received colchicines; 62 received other medications for gout treatment (Etoricoxib, glucocorticoid, Benzbromarone, allopurinol, Febuxostat, nonsteroidal antiinflammatory drugs or their combinations). Of 42 gout patients receiving colchicines, 23 were followed up. All tumor markers were detected by electrochemiluminescence immunoassays. Statistical analysis was performed by SPSS 17.0 software. RESULTS: The serum CA72-4 level was significantly higher in gout patients receiving colchicine than that in healthy control and gout patients without any treatment or who were receiving other treatments (P<0.001). There was no significant difference regarding other tumor markers among the various groups. All patients receiving colchicine, but no healthy individuals, patients with no treatment, or those receiving other medications had increased serum CA72-4 levels. Additionally, none or only a few of the subjects had increased AFP, CA19-9, CYFRA21-1, NSE, CEA, or PSA, while the proportion was not significantly different among various groups. CONCLUSIONS: Colchicine can cause abnormal elevation of serum CA72-4, but other medications have no effect on serum CA72-4. Furthermore, serum CA72-4 gradually increased and decreased after the initiation and cessation of colchicine therapy, respectively. Other tumor markers are not influenced by colchicine and other medications.

9.
Ophthalmology ; 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31543351

RESUMO

PURPOSE: To compare wear of standard, adjustable, and ready-made glasses among children. DESIGN: Randomized, controlled, open-label, noninferiority trial. PARTICIPANTS: Students aged 11 to 16 years with presenting visual acuity (VA) ≤6/12 in both eyes, correctable to ≥6/7.5, subjective spherical equivalent refractive error (SER) ≤-1.0 diopters (D), astigmatism and anisometropia both <2.00 D, and no other ocular abnormalities. METHODS: Participants were randomly allocated (1:1:1) to standard glasses, ready-made glasses, or adjustable glasses based on self-refraction. We recorded glasses wear on twice-weekly covert evaluation by head teachers (primary outcome), self-reported and investigator-observed wear, best-corrected visual acuity (BCVA) (not prespecified), children's satisfaction, and value attributed to glasses. MAIN OUTCOME MEASURE: Proportion of glasses wear on twice-weekly covert evaluation by head teachers over 2 months. RESULTS: Among 379 eligible participants, 127 were allocated to standard glasses (mean age, 13.7 years; standard deviation [SD], 1.0 years; 54.3% were male), 125 to ready-made (mean age, 13.6; SD, 0.83; 45.6%), and 127 to adjustable (mean age, 13.4 years; SD, 0.85; 54.3%). Mean wear proportion of adjustable glasses was significantly lower than for standard glasses (45% vs. 58%; P = 0.01), although the adjusted difference (90% confidence interval [CI], -19.0% to -3.0%) did not meet the prespecified inferiority threshold of 20%. Self-reported (90.2% vs. 84.8%, P = 0.64) and investigator-observed (44.1% vs. 33.9%, P = 0.89) wear did not differ between standard and adjustable glasses, nor did satisfaction with (P = 0.97) or value attributed to study glasses (P = 0.55) or increase in quality of life (5.53 [SD, 4.47] vs. 5.68 [SD, 4.34] on a 100-point scale, P > 0.30). Best-corrected visual acuity with adjustable glasses was better (P < 0.001) than with standard glasses. Change in power of study lenses at the end of the study (adjustable: 0.65 D, 95% CI, 0.52-0.79; standard, 0.01 D; 95% CI, -0.006 to 0.03, P < 0.001) was greater for adjustable glasses, although interobserver variation in power measurements may explain this. Lens scratches and frame damage were more common with adjustable glasses, whereas lens breakage was less common than for standard glasses. CONCLUSIONS: Proportion of wear was lower with adjustable glasses, although VA was better and measures of satisfaction and quality of life were not inferior to standard glasses.

10.
Curr Med Chem ; 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31538883

RESUMO

BACKGROUND: Fatty acid synthase (FAS or FASN) is a vital enzyme which catalyzes the de novo synthesis of long chain fatty acids. A number of studies have recently been reported that FAS was combined targets for the discovery of anti-obesity and anti-cancer drugs. Great interest has been developed in finding novel FAS inhibitors, and result in more than 200 inhibitors being reported. METHODS: The reported research literature about the FAS inhibitors was collected and analyzed through major databases including Web of Science, and PubMed. Then the chemical stractures, FAS inhibitory activities, and structure-activity relationships (SAR) were summarized focused on all these reported FAS inhibitors. RESULTS: The 248 FAS inhibitors, which were reported during the past 20 years, could be divided into thiolactone, butyrolactone and butyrolactam, polyphenols, alkaloids, terpenoids, and other structures, in view of their structure characteristics. And the SAR of high inhibitory structures of each type was proposed in this paper. CONCLUSION: A series of synthetic quinolinone derivatives show strongest inhibitory activity in the reported FAS inhibitors. Natural polyphenols, existing in food and herbs, show more adaptive in medicine exploration because of their safety and efficiency. Moreover, screening the FAS inhibitors from microorganism and marine natural products could be the hot research directions in the future.

11.
Opt Express ; 27(15): 20508-20515, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31510143

RESUMO

In this study, a biomimetic compound eye (BCE) was realized on diamond by combining thermal reflow with dry etching techniques. Firstly, photoresist pillars were developed on diamond surface by standard photolithography. Then, these pillars were reflowed on a hotplate to form spherical segment patterns. Furthermore, dry etching technique was used to transfer these patterns into diamond surface to form the convex curve surface with diameter of 300 µm, on which, ommatidia with diameter of 18 µm and space of 35 µm were fabricated with the same processes to obtain BCE. Finally, the as-fabricated diamond BCE was characterized, indicating a well-uniformity according to the point spread function and exhibiting clear images of the testing pattern in projection experiment, which is expected to work under harsh conditions such as high intensity irradiation and strong acid.

12.
Nucleic Acid Ther ; 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31513457

RESUMO

Amyloid-ß (Aß) plaque deposits in the brain are considered to be one of the main pathological markers of Alzheimer's disease (AD). The sequential proteolytic cleavage of amyloid precursor protein (APP) by the aspartyl proteases ß-site APP-cleaving enzyme 1 (BACE1) and γ-secretase produces Aß. Therefore, BACE1 inhibition is a very attractive target for the treatment of AD. Our previous work identified a DNA aptamer named A1 that can bind to BACE1 with high affinity and specificity and exhibits a distinct inhibitory effect on BACE1 activity in an AD cell model. The purpose of this research was to test the effect of aptamer A1 in Tg6799 mice. Four-month-old Tg6799 mice were randomly divided into two groups and treated with aptamer A1 and ineffective aptamer A1scr, respectively, by intracerebroventricular injection. Subsequent behavioral experiments showed that treatment with the aptamer A1 improved the cognitive abilities of the AD mice. Western blot indicated that BACE1 and soluble amyloid precursor protein ß (sAPPß) expression significantly decreased in the A1-treated mice. Moreover, aptamer A1 reduced the content of Aß42 and the number and density of senile plaques in AD mice. Therefore, our results indicate that aptamer A1 is a novel specific and potent BACE1 inhibitor and is a promising potential target for the treatment of AD.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31480157

RESUMO

Objective: We investigated the temporal expression profiles of long noncoding RNA (lncRNA) and mRNA in the peripheral blood of pigs during development and identified the lncRNAs that are related to the blood-based immune system. Methods: Peripheral blood samples were obtained from the pigs at 0, 7, 28 and 180 days and 2 years of age. RNA sequencing was performed to survey the lncRNA and mRNA transcriptomes in the samples. Short time-series expression miner (STEM) was used to show temporal expression patterns in the mRNAs and lncRNAs. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were performed to assess the genes' biological relevance. To predict the functions of the identified lncRNAs, we extracted mRNAs that were nearby loci and highly correlated with the lncRNAs. Results: In total of 5,946 lncRNA and 12,354 mRNA transcripts were identified among the samples. STEM showed that most lncRNAs and mRNAs had similar temporal expression patterns during development, indicating the expressional correlation and functional relatedness between them. The five stages were divided into two classes: the suckling period and the late developmental stage. Most genes were expressed at low level during the suckling period, but at higher level during the late stages. Expression of several T-cell-related genes increased continuously during the suckling period, indicating that these genes are crucial for establishing the adaptive immune system in piglets at this stage. Notably, lncRNA TCONS-00086451 may promote blood-based immune system development by upregulating nuclear factor of activated T-cells cytoplasmic 2 (NFATC2) expression. Conclusion: This study provides a catalog of porcine peripheral blood-related lncRNAs and mRNAs and reveals the characteristics and temporal expression profiles of these lncRNAs and mRNAs during peripheral blood development from the newborn to adult stages in pigs.

14.
J Geriatr Psychiatry Neurol ; 32(6): 336-343, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31480986

RESUMO

OBJECTIVE: This study investigated the association between small vessel disease (SVD) burden, a combination of multiple SVD markers and cognitive dysfunction after stroke. METHODS: The study sample comprised 451 patients with first-ever acute ischemic stroke. Cognitive functions were assessed with the Mini-Mental State Examination (MMSE) at 3, 9, and 15 months after the index stroke. Cognitive impairment was defined as an MMSE score of ≤26. A total SVD score, indicating SVD burden, was constructed by summing the scores of the 4 SVD markers (white matter hyperintensities [WMHs], lacunes, cerebral microbleeds, and perivascular spaces) ascertained by magnetic resonance imaging (range: 0-4). The association between SVD burden and cognitive dysfunction was assessed with linear mixed models or generalized estimating equation models, as appropriate. RESULTS: The majority of patients had mild-to-moderate stroke and at least one identifiable SVD marker. Cognitive impairment was found in about one-third of patients. After adjusting for confounding factors, the SVD burden was associated with MMSE scores (ß = -0.37, P = .003) and cognitive impairment (odds ratio [OR] = 1.20, 95% confidence interval [CI] = 1.02-1.42). SVD burden was specifically associated with the performance of MMSE subscores including orientation to place and time, calculation, and word recall. Of the SVD markers, WMHs was the most robust predictor of decrease in MMSE scores (ß = -0.25, P = .01) and cognitive impairment (OR = 1.14, 95% CI = 1.01-1.29). CONCLUSION: Cerebral SVD burden is associated with decreased MMSE scores, suggesting cognitive dysfunction during the first year after mild-to-moderate acute ischemic stroke.

15.
Water Res ; 166: 115041, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31536888

RESUMO

This study investigated formation and genotoxicities of disinfection by-products (DBPs) during chlorination of hydrophobic organic compounds (HOCs) extracted from six drinking water reservoirs around the Pearl River Delta region, China. Chemical analyses firstly showed that after chlorination aromatic HOCs (including polycyclic aromatic hydrocarbons, PAHs) decreased but DBPs (including chlorinated PAHs) increased, while genotoxicity assays revealed that the chlorination increased DNA damage in human Caco-2 cells. Although the link between DBPs and the genotoxicity was weak (insignificant correlations, p ≥ 0.05), we observed that chlorination of HOCs from more contaminated reservoirs in general resulted in higher genotoxicity. Secondly, remedial effects of catalase and dietary antioxidants (i.e. vitamin C and epigallocatechin gallate) in protecting cells against DBPs genotoxicity were detected. After 1 h treatment by the antioxidants, the DNA damage in Caco-2 cells (due to previous exposure to DBPs) significantly decreased (p < 0.05) in 7 out of a total of 18 treatments (38.9%). This is the first study demonstrating that catalase, vitamin C and epigallocatechin gallate protected human cells in vitro against DNA damage upon exposure to chlorinated genotoxic DBPs.

16.
ACS Appl Mater Interfaces ; 11(41): 37901-37907, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31549808

RESUMO

Currently, atomically thin materials with high photovoltaic performance are urgently needed for applications in solar cells. Herein, by using first-principles calculations, we propose an excellent two-dimensional photovoltaic material, monolayer HfTeSe4, which can be exfoliated feasibly from its layered bulk. It behaves in the semiconductor character with a moderate direct gap of 1.48 eV and exhibits remarkable absorbance coefficient of ∼105 cm-1 in the visible-light region. Meanwhile, monolayer HfTeSe4 shows ultrahigh photocurrent and a long carrier recombination lifetime. Also, strain engineering can further modulate the recombination time of carriers. Moreover, the heterostructure between HfTeSe4 and Bi2WO6 is proposed as potential solar cells with the solar conversion efficiency up to ∼20.8%. These extraordinary properties combined with its experimental feasibility makes monolayer HfTeSe4 particularly promising for photovoltaic device applications.

17.
Adv Mater ; 31(39): e1901964, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31389096

RESUMO

Atomically thin oxychalcogenides have been attracting intensive attention for their fascinating fundamental properties and application prospects. Bi2 O2 Se, a representative of layered oxychalcogenides, has emerged as an air-stable high-mobility 2D semiconductor that holds great promise for next-generation electronics. The preparation and device fabrication of high-quality Bi2 O2 Se crystals down to a few atomic layers remains a great challenge at present. Here, molecular beam epitaxy (MBE) of atomically thin Bi2 O2 Se films down to monolayer on SrTiO3 (001) substrate is achieved by co-evaporating Bi and Se precursors in oxygen atmosphere. The interfacial atomic arrangements of MBE-grown Bi2 O2 Se/SrTiO3 are unambiguously revealed, showing an atomically sharp interface and atom-to-atom alignment. Importantly, the electronic band structures of one-unit-cell (1-UC) thick Bi2 O2 Se films are observed by angle-resolved photoemission spectroscopy (ARPES), showing low effective mass of ≈0.15 m0 and bandgap of ≈0.8 eV. These results may be constructive to the synthesis of other 2D oxychalcogenides and investigation of novel physical properties.

18.
ACS Appl Mater Interfaces ; 11(38): 35060-35067, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31469272

RESUMO

Metal oxide hollow spheres (MOHSs) with multicomponent metal elements exhibit intriguing properties due to the synergistic effects of different components. However, it remains a great challenge to develop a general method to synthesize multicomponent MOHSs due to the different hydrolysis and condensation rates of precursors for different metal oxides. Herein, we demonstrate a general strategy for the controllable synthesis of MOHSs with up to five metal elements by decomposition of metal-phenolic coordination polymers (MPCPs), which are prepared by chelation of tannic acid with various metal ions. After calcination to burn out the organic component and induce heterogeneous contraction of MPCPs, a series of MOHSs with multishell structure, high specific surface area (55-171 m2/g), and crystalline mesoporous framework are synthesized, including binary (Fe-Co, Ni-Zn, and Ni-Co oxides), ternary (Ni-Co-Mn and Ni-Co-Zn oxides), and quinary (Ni-Co-Fe-Cu-Zn oxides) MOHSs. The gas sensing nanodevices based on quinary MOHSs show much higher response (10.91) than those based on single component toward 50 ppm of ethanol at 80 °C with the response/recovery time of 85/160 s. The quinary oxides sensor also displays high selectivity toward ethanol against other interfering gases (e.g., methanol, formadehyde, toluene, methane, and hydrogen) and long-term stability (∼94.0% after 4 weeks), which are extremely favorable for practical applications.

19.
Int J Nanomedicine ; 14: 4931-4947, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371941

RESUMO

Background: Phototherapy, including photothermal therapy (PTT) and photodynamic therapy (PDT), is a promising noninvasive strategy in the treatment of cancers due to its highly localized specificity to tumors and minimal side effects to normal tissues. However, single phototherapy often causes tumor recurrence which hinders its clinical applications. Therefore, developing a NIR-guided dendritic nanoplatform for improving the phototherapy effect and reducing the recurrence of tumors by synergistic chemotherapy and phototherapy is essential. Methods: A fluorescent targeting ligand, insisting of ICG derivative cypate and a tumor penetration peptide iRGD (CRGDKGPDC), was covalently combined with PAMAM dendrimer to prepare a single agent-based dendritic theranostic nanoplatform iRGD-cypate-PAMAM-DTX (RCPD). Results: Compared with free cypate, the resulted RCPD could generate enhanced singlet oxygen species while maintaining its fluorescence intensity and heat generation ability when subjected to NIR irradiation. Furthermore, our in vitro and in vivo therapeutic studies demonstrated that compared with phototherapy or chemotherapy alone, the combinatorial chemo-photo treatment of RCPD with the local exposure of NIR light can significantly improve anti-tumor efficiency and reduce the risk of recurrence of tumors. Conclusion: The multifunctional theranostic platform (RCPD) could be used as a promising method for NIR fluorescence image-guided combinatorial treatment of tumor cancers.


Assuntos
Antineoplásicos/farmacologia , Dendrímeros/química , Raios Infravermelhos , Nanopartículas/química , Fototerapia , Animais , Proliferação de Células/efeitos dos fármacos , Terapia Combinada , Docetaxel/farmacologia , Endocitose/efeitos dos fármacos , Fluorescência , Células Hep G2 , Temperatura Alta , Humanos , Indóis/farmacologia , Camundongos Nus , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Oligopeptídeos/química , Fotoquimioterapia , Propionatos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Nanomedicina Teranóstica
20.
Biotechnol Lett ; 41(10): 1105-1110, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31407133

RESUMO

Atomic force microscopy (AFM) is a sophisticated imaging tool with nanoscale resolution that is widely used in structural biology, cell biology, and material science, among other fields. However, to date it has rarely been applied to the study of aquatic animals, especially on one of the main cultured species, shrimp. One reason for this is that no shrimp cell line established until now, primary cell is fragile and difficult to be studied under AFM. In this study, we used AFM to image three different types of biological material from shrimp (Litopenaeus vannamei) in air, including hemocytes and two associated pathogens. Without obvious deformations when the cells were imaged in air and in the case for the haemocytes and the cells were fixed as well. The result suggests hydrophobic glass coverslips are a suitable substrate for adhesion of these samples. The method described here can be applied to the preparation of other fragile biological samples from aquatic animals for high-resolution analyses of host-pathogen interactions and other basic physiological processes.

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