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1.
Sci Total Environ ; 721: 137639, 2020 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-32172103

RESUMO

Mercury is a key global pollutant, yet the mechanism by which mercury-exposure causes intestinal injury is not clear, we aimed to investigate the mechanism of intestinal injury and gut microbiota changes caused by mercury-exposure. Twelve Kunming mice were divided into two groups (n = 6), and the two groups were treated with 0 mg/L and 80 mg/L HgCl2 in drinking water for 90 days respectively. Our results showed that mercury-exposure prominently effected body weight gain and glucose levels. The mercury-exposed mice showed intestinal injury, which was diagnosed by Histopathological Examination and Transmission Electron Microscopy. Meanwhile, RT-PCR indicated that mercury-exposure significantly increased the expression of pro-apoptotic genes including Bax, JNK, ASK1, caspase3 and TNF-α, and significantly decreased the expression of the anti-apoptotic gene Bcl-2. Furthermore, high-throughput sequencing analysis showed that at the genus level some microbial populations including Coprococcus, Oscillospira and Helicobacter were significantly increased whereas some microbial populations including Lgnatzschineria, Salinicoccus and Bacillus were significantly decreased. Moreover, PICRUSt analysis revealed potential metabolic changes. Correlation analysis indicated that microorganisms were significantly correlated with apoptotic gene expression. In summary, our results indicated that mercury-exposure affected the growth and development of mice, induced intestinal microbiota dysbiosis and metabolic disorder, and aggravated apoptosis in mice.

2.
Sci Total Environ ; 723: 137991, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32213407

RESUMO

Biochar has been received increasing concerns regarding its environmental effect, which is promising in wastewater treatment. In this study, the performance of ß-cyclodextrin functionalized biochar (ß-BC) on the removal of antibiotic resistance genes (ARGs) in wastewater treatment under the co-stresses of heavy metals and dye is evaluated. Results show that when 20 mg/L heavy metals (HMs) and 150 mg/L methyl orange (MO) are present in daily fed influent, only 0.05 mg/L HMs residual and 96.79%-98.84% MO removal efficiency achieved in ß-BC additive group, compare to 0.16 mg/L and 87.92%-94.11% of that in control, respectively, indicating that ß-BC can benefits the performance of contaminants removal. To evaluate the role of ß-BC plays on ARGs in multi-contaminants stressed system, tet W, tet M, sul-1, sul-2, blaTEM, oxa-1, qnr-S, erm-B and intI-1 are identified. The relative abundance of all identified ARGs are decreased when ß-BC presence compared to the corresponding groups without ß-BC additive. The diversity and composition of microbial community are explored and the reduction of potential antibiotic-resistant bacteria is speculated as a driver of ARGs removal. In conclusion, our study demonstrates that ß-BC possesses the ability to promote the removal of ARGs during continuous wastewater treatment under HMs-MO co-contaminant.

3.
Int J Med Sci ; 17(6): 799-806, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32218701

RESUMO

Our study investigated the expression of malic enzyme 2 (ME2) in human oral squamous cell carcinoma (OSCC) and associated pathological and clinical pattern. We demonstrated that human OSCC tissues expressed a high level of ME2, and the overexpression of ME2 is closely connected to a high pathological grade, lymphatic metastasis, large tumor size and human papillomavirus (HPV) (P < 0.001). Similarly, high levels of ME2 expression in OSCC tissue were shown to be correlated with poor prognosis (P < 0.05). The expression of ME2 was correlated with Slug, SOX2, and aldehyde dehydrogenase-1 (ALDH1) immunoreactivity.ME2 was shown to be overexpressed in OSCC tissue and indicated a poor prognosis for OSCC. ME2 may be correlated with several immune markers.

4.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(1): 130-135, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32027265

RESUMO

OBJECTIVE: To study the expression level of TGFß1 and VEGF gene in patients with acute myeloid leukemia (AML) and its clinical prognostic value. METHODS: Seventy-eight AML patients treated in our hospital from July 2016 to September 2018 were selected. After isolation of bone marrow mononuclear cells from the patients, the levels of TGFß1 and VEGF genes were detected by RT-PCR, and the correlation of TGFß1 with VEGF genes and clinical characteristics of AML patients was analyzed. OS and EFS of the patients were evaluated by Kaplan-Meier, and Cox risk ratio model was used to analyze the prognostic risk factors of AML patients. RESULTS: The relative expression level of TGFß1 gene in AML patients was 0.32±0.04, which was significantly lower than that in control group (P<005). The relative expression level of vascular endothelial growth factor(VEGF) gene in the patients was 2.65±0.15, which was significantly higher than that in the control group (P<0.05). The levels of TGFß1 and VEGF genes significantly correlated with leukocyte count, hemoglobin, platelet and peripheral blast levels in AML patients (P<0.05). The level of TGFß1 in AML patients with complete remission was higher than that in patients with partial remission or non-remission (P<0.05). The level of TGFß1 in AML patients with partial remission was significantly higher than that in patients with non-remission (P<0.05). The level of VEGF in AML patients with complete remission was lower than at in patients with partial remission or non-remission (P<0.05). The level of VEGF in AML patients with partial remission was significantly lower than that in patients with non-remission (P<0.05). Kaplan-Meier survival analysis showed that OS and DFS in AML patients with high expression of TGFß1 were better than those in patients with low expression of TGFß1 (P<0.05), OS and DFS in AML patients with low expression of VEGF were better than those in patients with high expression of VEGF (P<0.05). Multivariate Cox regression analysis showed that platelet, TGFß1 and VEGF gene were independent influencing factors of OS (P<0.05). Leukocyte, TGFß1 and VEGF gene were independent influencing factors of DFS (P<0.05). CONCLUSION: Decreased expression of TGFß1 and increased expression of VEGF gene in AML patients closely relate to the poor prognosis of AML patients, which can provide reference for improving clinical efficacy of AML patients.


Assuntos
Leucemia Mieloide Aguda , Fator de Crescimento Transformador beta1/genética , Fator A de Crescimento do Endotélio Vascular/genética , Humanos , Estimativa de Kaplan-Meier , Leucemia Mieloide Aguda/genética , Prognóstico , Indução de Remissão
5.
Environ Pollut ; 261: 114109, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32109818

RESUMO

Dichlorvos is a common crop insecticide widely used by people which causes extensive and serious environmental pollution. However, it has been shown that organophosphorus poisoning causes energy metabolism and neural disorders. The overall purpose of this study was to investigate the damage to brain tissue and the changes in AMPK signaling pathway-related gene expression after dichlorvos poisoning in chickens. White-feathered broiler chickens, as the research subjects of this experiment, were divided into three groups: control group, low-dose group (77.5% dichlorvos at 1.13 mg/kg dose) and high-dose group (77.5% dichlorvos at 10.2 mg/kg dose). Clinical symptoms were observed after modeling, and an integrative analysis was conducted using HE staining microscopy, immune-histochemical microscopy, electron microscopy and PCR arrays. The results showed that the high-dose group had more obvious dyspnea, salivation, convulsion and other neurological phenomena. Pathological sections showed that nuclear disintegration of neurons was most obvious in the low-dose group, and apoptosis of brain cells was most obvious in the high-dose group, and the mitochondrial structure was destroyed in the two poisoned group, i.e. low-dose group and high-dose group. PCR arrays showed that AMPK signaling pathway was inhibited and the expressions of genes involved in energy metabolism (ACACA and PRKAA1) were significantly changed. Furthermore, genes associated with protein synthesis (EIF4EBP1) were significantly upregulated. FASN and HMGCR expressions were significantly increased. There were significant changes in the expressions of cell cycle-related genes (STK11, TP53 and FOXO3). Organophosphate poisoning can cause a lot of nuclear disintegration of brain neurons, increases cell apoptosis, disrupts the energy metabolism of mitochondrial structure, and inhibits the AMPK signaling pathway. These results provide a certain idea and basis for studying the mechanism of AMPK signaling after organophosphorus poisoning and provide a research basis for the prevention and treatment of organophosphorus poisoning.

6.
Eur J Oral Sci ; 128(1): 37-45, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32027770

RESUMO

Inositol polyphosphate 4-phosphatase type II (INPP4B) is a phosphoinositide phosphatase that plays complex roles in the pathogenesis of different tumors. We aimed to explore the expression, clinicopathological significance, and prognostic value of INPP4B in oral squamous cell carcinoma (OSCC). Tissue microarrays that included samples from 176 primary OSCCs, 42 normal mucosae, and 69 dysplastic tissues were used for immunostaining analyses of INPP4B protein. Aperio ScanScope CS scanner and aperio quantification software were used to scan the microarrays and score the staining, respectively. We also evaluated the correlation between INPP4B expression and clinical parameters, pathological grades, node-positive status, and immune-related markers. Expression of INPP4B was statistically significantly upregulated in human primary OSCC tissues compared with dysplastic and normal tissues. Additionally, we found that patients with strong expression of INPP4B had a statistically significantly poorer overall survival than patients with weak expression of INPP4B. Furthermore, our study indicated that expression of INPP4B in OSCC was positively associated with expression of p-S6Ser235/236 , p-CADSer1859 , and certain immune checkpoints (B7-H4, Galectin-9). Therefore, INPP4B may be an independent prognostic indicator for patients with OSCC, in which it might function as an oncoprotein.

7.
J Biomed Nanotechnol ; 16(1): 1-13, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31996281

RESUMO

Targeted drug delivery systems have currently demonstrated considerable potential clinical benefits in cancer treatment. Curcumin has become a candidate anti-tumor drug for the therapy of glioblastoma multiforme (GBM) by increasing cell apoptosis and suppressing cell proliferation. In current research, we explored a novel targeted drug delivery system with a self-assembly measure by curcumin, MPEG-PLA and Fa-PEG-PLA. Compared with free curcumin and Cur/MPEG-PLA, Cur/Fa-PEG-PLA can remarkably suppress the growth of GL261 cells and promote apoptotic rate. Moreover, after the procession of tumor-bearing mice with curcumin/Fa-PEG-PLA complex, tumor growth in subcutaneous and intracranial tumor models were repressed via suppressing angiogenesis and facilitating apoptosis in vivo. The Curcumin/Fa-PEG-PLA nanoparticle may be a novel drug for the therapy of GBM.


Assuntos
Curcumina , Glioma , Animais , Antineoplásicos , Linhagem Celular Tumoral , Portadores de Fármacos , Ácido Fólico , Camundongos , Micelas , Polietilenoglicóis
8.
Am J Clin Pathol ; 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31977029

RESUMO

OBJECTIVES: Interferon-induced protein with tetratricopeptide repeats 1 (IFIT1) and interferon-induced transmembrane protein 3 (IFITM3) are commonly induced by type I interferon. The study aims to investigate the expression and clinical significance of IFIT1 and IFITM3 in head and neck squamous cell carcinoma (HNSCC). METHODS: Immunohistochemistry was applied on tissue microarray to reveal IFIT1 and IFITM3 expression in 275 HNSCC, 69 dysplasia, and 42 normal mucosa samples. The clinicopathologic features associated with IFIT1 and IFITM3 expression in HNSCC patients were analyzed. RESULTS: IFIT1 and IFITM3 were highly expressed in HNSCC tissues. High expression of IFIT1 and IFITM3 predicts a negative prognosis for patients (P < .01). IFIT1 and IFITM3 expression was associated with programmed cell death ligand 1, B7-H4, V-domain Ig suppressor of T-cell activation, indoleamine 2,3-dioxygenase, and macrophage marker immunoreactivity. CONCLUSIONS: IFIT1 and IFITM3 were overexpressed in HNSCC and indicated poor prognoses for patients with HNSCC. IFIT1 and IFITM3 expression was correlated with several immune checkpoint molecules and tumor-associated macrophage markers.

9.
ChemMedChem ; 15(1): 17-25, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31674143

RESUMO

The ability to selectively degrade proteins with bifunctional small molecules has the potential to fundamentally alter therapy in a variety of diseases. However, the relatively large size of these chimeric molecules often results in challenging physico-chemical properties (e. g., low aqueous solubility) and poor pharmacokinetics which may complicate their in vivo applications. We recently discovered an exquisitely potent chimeric BET degrader (GNE-987) which exhibited picomolar cell potencies but also demonstrated low in vivo exposures. In an effort to improve the pharmacokinetic properties of this molecule, we discovered the first degrader-antibody conjugate by attaching GNE-987 to an anti-CLL1 antibody via a novel linker. A single IV dose of the conjugate afforded sustained in vivo exposures that resulted in antigen-specific tumor regressions. Enhancement of a chimeric protein degrader with poor in vivo properties through antibody conjugation thereby expands the utility of directed protein degradation as both a biological tool and a therapeutic possibility.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31606425

RESUMO

OBJECTIVE: This study aimed to explore the relationship between the expression of the coxsackie-adenovirus receptor (CAR) in oral squamous cell carcinoma (OSCC) and the clinicopathologic parameters associated with the disease. The diagnostic and prognostic potential of CAR in OSCC was also investigated. STUDY DESIGN: Immunohistochemistry was performed on human tissue microarrays, containing 42 oral mucosa, 69 dysplasia, and 176 OSCC tissue sections, to reveal the expression pattern of CAR. Statistical analysis was used to determine the correlation between CAR expression and the patient survival rate as a measure of the prognostic value of CAR. RESULTS: CAR was overexpressed in human OSCC tissues (P = .002), and higher expression of CAR was associated with a lower survival rate, which was not statistically significant (P = .123). In addition, patients with OSCC in the human papillomavirus (HPV)-positive group showed significantly higher CAR expression compared with the HPV- negative group (P = .0491). CONCLUSIONS: This study indicated that CAR expression was upregulated in human OSCC and that patients with OSCC with higher expression of CAR had a lower survival rate. Moreover, CAR expression may be associated with HPV infection.

11.
Biol Trace Elem Res ; 193(2): 445-455, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31147976

RESUMO

The aim of the present study was to investigate the effects of high concentrations of copper (Cu) on the cecum and rectum of intestinal microbiota in female mice. Twenty-four Kunming mice were weighed and randomly divided into two groups (n = 12 per group) including the control group and Cu group. Cu group was given drinking water with 5 mg/kg-bw copper chloride (CuCl2), while the control group was treated with drinking water without CuCl2. At the 90th day, results showed that compared with the control group, mice in the treatment group had a lower body weight, and the feces turned yellow and had a lower pH value. Histopathological lesions showed that the intestinal tissue from the treatment group had increased thickness of outer muscularis and smoothed muscle fiber, widened submucosa, decreased goblet cells, and showed blunting of intestinal villi and severe atrophy of central lacteal. In addition, at the genus level, 16S rRNA gene sequencing from the Cu group showed that Corynebacterium were significantly increased whereas Staphylococcaceae, Odoribacter, Rikenella, and Jeotgalicoccus were significantly decreased in the cecum. Dehalobacterium, Coprococcus, and Spirochaetales increased significantly whereas Salinicoccus, Bacillales, Staphylococcus, and Lactobacillales decreased sharply in the rectum. This study demonstrated that high concentrations of Cu could induce tissue injury and interrupt the homeostasis of microbiota.

12.
IEEE Trans Vis Comput Graph ; 26(1): 790-799, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31442982

RESUMO

Interactive visualization and exploration of large spatiotemporal data sets is difficult without carefully-designed data pre-processing and management tools. We propose a novel architecture for spatiotemporal data management. The architecture can dynamically update itself based on user queries. Datasets is stored in a tree-like structure to support memory sharing among cuboids in a logical structure of data cubes. An update mechanism is designed to create or remove cuboids on it, according to the analysis of the user queries, with the consideration of memory size limitation. Data structure is dynamically optimized according to different user queries. During a query process, user queries are recorded to predict the performance increment of the new cuboid. The creation or deletion of a cuboid is determined by performance increment. Experiment results show that our prototype system deliveries good performance towards user queries on different spatiotemporal datasets, which costing small memory size with comparable performance compared with other state-of-the-art algorithms.

13.
ACS Appl Mater Interfaces ; 11(51): 47680-47694, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31789503

RESUMO

Ultrafine-grained pure (UFG) titanium processed by equal channel angular pressing possesses mechanical properties comparable to those of Ti-6Al-4V and features more favorable friction resistance, biocompatibility, and corrosion resistance than does commercially pure (CP) titanium. Nevertheless, UFG titanium is still a bio-inert material with a lack of bone-inducing ability. Here, TiO2-hydroxyapatite (TiO2-HA) coatings were fabricated on CP titanium and UFG titanium through combining micro-arc oxidation and hydrothermal treatment together to improve their cytocompatibility. The results indicate that, compared with conventional coatings that use CP titanium as the substrate, such coatings formed on the UFG titanium possess additional hydrophilicity and in vitro cytocompatibility. The fantastic hierarchical structure of the UFG TiO2-HA coating (UG-MH coating), including microscale and nanoscale pores and short column-shaped and sheet-shaped HA grains with varying geometric shapes, excellent hydrophilicity, and high polar force, enhances the mutual effects between the osteoblasts and titanium implant since it provides an adequate microenvironment for the ingrowth of osteoblasts, inducing osteoblast adhesion, proliferation, and differentiation. The UG-MH coating has a synergistic effect due to its fantastic hydrophilic hierarchical structure and high polar force on the up-regulated expression of cytoskeletal actin proteins as well as osteocalcin, protein kinase C (PKC), nuclear factor of activated T-cells (NFAT), and Wnt5, enabling osteoblasts to differentiate via the Wnt calcium-dependent signaling pathway. This study highlights the idea that the modified UFG titanium will be more suitable than CP titanium in dental and orthopedic applications.

14.
Environ Toxicol ; 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31855318

RESUMO

Although the inhibitory roles of ursolic acid (UA) have been established in various tumors, its effects on the stemness of non-small cell lung cancer (NSCLC) cells are still unclear. Here, we constructed NSCLC cells with paclitaxel resistance (A549-PR) and showed that A549-PR exhibited a remarkably stronger stemness than the parental A549 cells, which is evident by the increase of spheroid formation capacity, stemness marker expression, and ALDH1 activity. Additionally, UA significantly reduced the stemness and paclitaxel resistance of A549-PR cells. Mechanistic investigations revealed that UA inhibited the miR-149-5p/MyD88 signaling, which is responsible for UA-mediated effects on the stemness of A549-PR cells. Notably, miR-149-5p/MyD88 axis promoted the stemness of A549 cells, while inhibition of this axis attenuated the stemness of A549-PR cells. Therefore, these results suggest that UA could attenuate the stemness and chemoresistance of NSCLC cells through targeting miR-149-5p/MyD88 axis.

15.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(10): 1196-1202, 2019 Oct 28.
Artigo em Chinês | MEDLINE | ID: mdl-31857516

RESUMO

The advent of catheter ablation technology has changed the treatment strategy for atrial fibrillation, and the efficacy of catheter ablation is accurate with small surgical trauma. Catheter ablation treatment of atrial fibrillation is significantly better than pharmacologic therapy of anti-arrhythmia and rate control. However, the clinic data of catheter ablation of atrial fibrillation show that the recurrence rate is high. The risk factors for recurrence after catheter ablation include age, sex, body mass index, related primary disease, left atrial volume, pulmonary vein volume, gene, atrial fibrillation types, surgery and so on. Regulation of the above factors is crucial in improving the clinical efficacy and prognosis of catheter ablation of atrial fibrillation.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Antiarrítmicos , Humanos , Recidiva , Fatores de Risco , Resultado do Tratamento
16.
Lab Chip ; 19(21): 3714-3725, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31584051

RESUMO

Arbitrary patterning of micro-objects in liquid is crucial to many biomedical applications. Among conventional methodologies, acoustic approaches provide superior biocompatibility but are intrinsically limited to producing periodic patterns at low resolution due to the nature of standing waves and the coupling between fluid and structure vibrations. This work demonstrates a near-field acoustic platform capable of synthesizing high resolution, complex and non-periodic energy potential wells. A thin and viscoelastic membrane is utilized to modulate the acoustic wavefront on a deep, sub-wavelength scale by suppressing the structural vibration selectively on the platform. Using 3 MHz excitation (λ∼ 500 µm in water), we have experimentally validated such a concept by realizing patterning of microparticles and cells with a line resolution of 50 µm (one tenth of the wavelength). Furthermore, massively parallel patterning across a 3 × 3 mm2 area has been achieved. This new acoustic wavefront modulation mechanism is powerful for manufacturing complex biologic products.

17.
Int J Nanomedicine ; 14: 7515-7531, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31571861

RESUMO

Background: Glioblastoma mutliforme is the most common and has the poorest prognosis of any malignant tumor of the central nervous system. Luteolin, the most abundant xanthone extracted from vegetables and medicinal plants, has been shown to have treatment effects in various cancer cell types. Luteolin is however, hydrophobic and has poor biocompatibility, which leads to low bioavailability. Patients and methods: In this study, folic acid modifiedpoly(ethylene glycol)-poly(e-caprolactone) (Fa-PEG-PCL) nano-micelles was used to encapsulate the luteolin, creating luteolin loaded PEG-PCL (Lut/Fa-PEG-PCL) micelles to treat glioma both in vitro and in vivo. Results: When compared with the free luteolin and Lut/MPEG-PCL, Lut/Fa-PEG-PCL induced a significant cell growth inhibition and more apoptosis of GL261 cells both in vitro and in vivo. The safety assessment also showed no obvious side effects were observed in mice which were administrated with free luteolin or Lut/MPEG-PCL and Lut/Fa-PEG-PCL. Conclusion: These results suggested Lut/Fa-PEG-PCL may be used as an excellent intravenously injectable formulation for the treatment and chemoprevention.


Assuntos
Sistemas de Liberação de Medicamentos , Ácido Fólico/química , Glioma/tratamento farmacológico , Luteolina/uso terapêutico , Nanopartículas/química , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Liberação Controlada de Fármacos , Glioma/irrigação sanguínea , Humanos , Luteolina/farmacocinética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Nus , Micelas , Modelos Moleculares , Nanopartículas/ultraestrutura , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Poliésteres/química , Polietilenoglicóis/química , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos Sprague-Dawley
18.
Chemosphere ; 226: 907-914, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31509920

RESUMO

The isomorphous substitution in the structure of phyllosilicate minerals plays an important role in regulating of surface chemical properties. In this work, iron muscovite nanoparticles with various Al species were successfully prepared to explore the structural Fe and Al species on the capture of Cd(II) from solutions. The synthesized nanocrystals have irregular shapes with diameters of 10-50 nm. The incorporation of Al(III) into the iron muscovite nanostructure has slight effect on the species of Fe and the crystal phase of the products. The degree of Al(III) substituting Si(IV) in the tetrahedral sheets of the minerals obviously increased with increasing of Al doping levels. For the samples with low Al doping levels (5% and 10%), the adsorption capacity of the iron muscovite nanoparticles for Cd(II) increased slightly. With increasing of Al doping ratio to 15%, the obtained iron muscovite nanoparticles exhibited a maximal uptake of 41.4 mg g-1 for Cd(II), which is about two times that of the undoped samples (22.8 mg g-1). The solution pH had a slight effect on the Cd (II) capture at a wide pH range from 4 to 8. The adsorption of Cd(II) is very fast and reached a steady state within 5 min. Desorption results showed that the binding strength between Cd(II) and iron muscovite nanoparticles was obviously enhanced by incorporation of Al at a high level. The ion exchange and surface complexation are principal mechanisms in the Cd(II) capture by the iron muscovite nanomaterials with various structural Al species.


Assuntos
Silicatos de Alumínio/química , Alumínio/química , Cádmio/isolamento & purificação , Ferro/química , Nanopartículas/química , Adsorção , Cádmio/química , Concentração de Íons de Hidrogênio , Propriedades de Superfície
19.
ACS Nano ; 13(9): 10835-10844, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31487464

RESUMO

Efficient intracellular delivery of biomolecules into cells that grow in suspension is of great interest for biomedical research, such as for applications in cancer immunotherapy. Although tremendous effort has been expended, it remains challenging for existing transfer platforms to deliver materials efficiently into suspension cells. Here, we demonstrate a high-efficiency photothermal delivery approach for suspension cells using sharp nanoscale metal-coated tips positioned at the edge of microwells, which provide controllable membrane disruption for each cell in an array. Self-aligned microfabrication generates a uniform microwell array with three-dimensional nanoscale metallic sharp tip structures. Suspension cells self-position by gravity within each microwell in direct contact with eight sharp tips, where laser-induced cavitation bubbles generate transient pores in the cell membrane to facilitate intracellular delivery of extracellular cargo. A range of cargo sizes were tested on this platform using Ramos suspension B cells with an efficiency of >84% for Calcein green (0.6 kDa) and >45% for FITC-dextran (2000 kDa), with retained viability of >96% and a throughput of >100 000 cells delivered per minute. The bacterial enzyme ß-lactamase (29 kDa) was delivered into Ramos B cells and retained its biological activity, whereas a green fluorescence protein expression plasmid was delivered into Ramos B cells with a transfection efficiency of >58%, and a viability of >89% achieved.

20.
Nanotechnology ; 30(42): 425404, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31386632

RESUMO

Transition metal oxides (TMOs) as anode materials have potential for lithium-ion batteries (LIBs). However, the poor rate capacity and cycle stability restrict its application. Herein, we demonstrate a facile one-step hydrothermal method to construct a three-dimensional porous conductive network structure, which consists of thin-layered graphene, ultrafine Co3O4-CoO nanoparticles and nitrogen-doped carbon. This unique structure can effectively prevent particle agglomeration and cracking caused by volume expansion, provide fast passage for lithium ion/electron transport during cycling and improve the electrical conductivity of the electrode. Moreover, the electrochemical kinetic analysis proves that this is a process dominated by pseudocapacitive behavior. Consequently, the N-C@Co3O4-CoO@GO hybrid electrode delivers an ultrahigh capacity of 1 273.1 mA h g-1 at 0.1 A g-1 and superior rate performance (725.1 mA h g-1 at 5 A g-1). Additionally, it exhibits a high reversible cycling capacity of 787.4 mA h g-1 at 1 A g-1 over 600 cycles and even maintains excellent cycling stability for a ultra-long cycles at 5 A g-1. This work provides a feasible strategy for fabricating the N-C@Co3O4-CoO@GO composite as a promising high-performance TMOs anode for LIBs.

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