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1.
Anal Chem ; 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33596054

RESUMO

The aim of this study was to identify the target of nonalcoholic fatty liver disease (NAFLD) cell-specific aptamer NAFLD01 and investigate its effect on lipid metabolism in vitro. A distinct membrane protein of NAFLD cells pulled down by NAFLD01 was analyzed by mass spectrometry to determine target candidates, and affinity of NAFLD01 to target-protein-silent NAFLD cells was detected to validate it. Knockdown of CD36 abolished the binding of NAFLD01, and its binding affinity was associated with membrane-bound CD36. NAFLD01 affinity for NAFLD cells was proportional to the CD36 expression level. Moreover, compared to random sequences, NAFLD01 showed better recognition for both mouse and human tissue sections of NAFLD. Importantly, NAFLD01 could ameliorate liver fat deposition through interaction with CD36 in vitro. Therefore, aptamer NAFLD01 could act as an effective and safe targeted drug for NAFLD. NAFLD01 is the first reported CD36-specific aptamer. This aptamer can improve hepatocyte steatosis via specifically binding to CD36. This study provides a molecular tool to investigate the mechanism of CD36 in NAFLD.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33464818

RESUMO

We demonstrate that the photoactivity of bismuth oxyiodide (BiOI) nanoflake (NF) photocathodes in photo-electrochemical (PEC) water splitting can be significantly enhanced by about 24-fold by thermal calcination under an air atmosphere and then surficial decoration of Au nanoparticles (NPs). To understand the key factors affecting the PEC efficiency in Au NP-decorated BiOI NF photoelectrodes, incident photon-to-current conversion efficiency, electrochemical impedance spectroscopy, photovoltage, and electrochemically active surface area measurements were performed. The analytic results presented that thermal calcining could produce mesopores, increasing active sites on the surface of BiOI NFs. In addition, the synergistic effects of surface-state passivation and charge separation were observed for the surficial Au NP decoration on BiOI NFs. Transient absorption spectroscopy coupled with PEC measurements confirmed that the lifetime of photogenerated electrons on the conduction band of BiOI NFs can be prolonged by Au NP decoration, resulting in higher probability to carry out water reduction. The current investigation presents important insights into the mechanism of charge carrier dynamics in metal-semiconductor nano-heterostructures, which is contributive to develop photoelectrode materials in solar fuel production.

3.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 49(5): 609-613, 2020 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-33210488

RESUMO

OBJECTIVE: To compare three sterilizing methods for reusable medical goggles. METHODS: A total of 180 medical goggles of the same brand and same model were randomly divided into three groups. In group A the goggles were first soaked with 2000 mg/L chlorine-containing disinfectant and then cleaned manually; goggles in other two groups were sterilized using pre-programmed automatic spray cleaning and disinfection machine, the disinfection program was set to 90 ℃ for 5 min in group B and 70 ℃ for 30 min in group C. The quality of the sterilization was monitored by visual inspection with luminous magnifying glass and residual protein detection assay. User satisfaction on cleanliness of medical goggles, clarity of mirror surface and suitability of elastic bands was investigated with questionnaire survey. RESULTS: The qualification rates verified by visual inspection were 82.4%, 84.6%and 98.3%in group A, B and C, respectively, the qualification rate in group C was significantly higher than those in group B and group C (all P<0.05). The qualification rates verified by residual protein detection assay were 96.7%, 100.0%and 100.0%in group A, B and C, respectively (P>0.05). A total of 54 questionnaires were submitted for the survey. The satisfaction rates were 100.0%, 90.7%and 94.4% for cleanliness of medical goggles, clarity of mirror surface and suitability of elastic bands, respectively. CONCLUSIONS: Machinery sterilization set 70 ℃ for 30 min has better cleaning and sterilizing effects for reusable medical goggles.


Assuntos
Dispositivos de Proteção dos Olhos , Esterilização , Dispositivos de Proteção dos Olhos/normas , Esterilização/métodos , Inquéritos e Questionários
4.
Drug Des Devel Ther ; 14: 3393-3405, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32884242

RESUMO

Background: Previous studies have shown that curcumin derivatives can improve the fatty degeneration of liver tissue that occurs in nonalcoholic fatty liver disease (NAFLD). However, the specific mechanism for that improvement remains unclear. We examined whether the curcumin derivative galangin could reduce the fatty degeneration of liver tissue in mice with NAFLD by inducing autophagy, from the perspective of both prevention and treatment. Methods: C57BL/6J mice were randomly assigned to a prevention group (given galangin and a HFD simultaneously) or a treatment group (given galangin after being fed an HFD). The prevention group was treated with galangin (100 mg/kg/d) or an equal volume of normal saline (NS) while being fed an HFD. Some mice were treated with an autophagy inhibitor (3-methyladenine, 3-MA; 30 mg/kg/biwk, i.p.) while being fed an HFD and galangin. HepG2 cells were cultured in DMEM medium containing both free fatty acids and galangin. Results: Galangin was found to reduce the fatty degeneration of liver tissue induced by eating an HFD at both the prevention and treatment levels, and that effect might be related to an enhancement of hepatocyte autophagy. Inhibition of autophagy by 3-MA blocked the protective effect of galangin on hepatic steatosis. At the cellular level, galangin reduced lipid accumulation and enhanced the level of hepatocyte autophagy. Conclusion: In vitro and in vivo studies showed that galangin cannot only improve pre-existing hepatic steatosis but also prevent the development of stenosis by promoting hepatocyte autophagy.

5.
Sustain Cities Soc ; 63: 102466, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32904401

RESUMO

The novel human coronavirus (SARS-CoV-2) causes the coronavirus disease 2019 (COVID-19) pandemic worldwide. Control of COVID-19 pandemic is vital for public health and is the prerequisite to maintain social stability. However, the origin and transmission route of SARS-CoV-2 is unclear, bringing huge difficult to virus control. Monitoring viral variation and screening functional mutation sites are crucial for prevention and control of infectious diseases. In this study, we developed a user-friendly software, named BioAider, for quick sequence annotation and mutation analysis on large-scale genome-sequencing data. Herein, we detected 14 substitution hotspots within 3,240 SARS-CoV-2 genome sequences, including 3 groups of potentially linked substitution. NSP13-Y541C was crucial substitution which might affect the unwinding activity of the viral helicase. In particular, we discovered a SR-rich region of SARS-CoV-2 distinct from SARS-CoV, indicating more complex replication mechanism and unique N-M interaction of SARS-CoV-2. Interestingly, the quantity of SSRX repeat fragments in SARS-CoV-2 provided further evidence of its animal origin. Overall, we developed an efficient tool for rapid identification of viral genome mutations which could facilitate viral genomic studies. Using this tool, we have found critical clues for the transmission route of SARS-CoV-2 which would provide theoretical support for the epidemic control of pathogenic coronaviruses.

6.
Sustain Cities Soc ; 61: 102413, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32834932

RESUMO

The ongoing coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has imposed a significant impact on social and economic activities. As a high infectious pathogen, the existence of SARS-CoV-2 in public space is very important for its transmission. During the COVID-19 pandemic, hospitals are the main places to deal with the diseases. In this work, we evaluated the exposure risk of SARS-CoV-2 in hospital environment in order to protect healthcare workers (HCWs). Briefly, air and surface samples from 6 different sites of 3 hospitals with different protection levels were collected and tested for the SARS-CoV-2 nucleic acid by reverse transcription real-time fluorescence PCR method during the COVID-19 epidemic. We found that the positive rate of SARS-CoV-2 nucleic acid was 7.7 % in a COVID-19 respiratory investigation wards and 82.6 % in a ICUs with confirmed COVID-19 patients. These results indicated that in some wards of the hospital, such as ICUs occupied by COVID-19 patients, the nucleic acid of SARS-CoV-2 existed in the air and surface, which indicates the potential occupational exposure risk of HCWs. This study has clarified retention of SARS-CoV-2 in different sites of hospital, suggesting that it is necessary to monitor and disinfect the SARS-CoV-2 in hospital environment during COVID-19 pandemic, and will help to prevent the iatrogenic infection and nosocomial transmission of SARS-CoV-2 and to better protect the HCWs.

8.
J Agric Food Chem ; 68(31): 8132-8142, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32649185

RESUMO

Xanthomonas oryzae pv. oryzae (Xoo) is an offensive phytopathogen that can invade a wide range of plant hosts to develop bacterial diseases, including the well-known rice bacterial leaf blight. However, few agrochemicals have been identified to effectively prevent and eliminate Xoo-induced diseases. Thus, designing novel antibacterial compounds on the basis of the potential targets from Xoo may lead to the discovery of highly efficient and innovative anti-Xoo agents. Filamentous temperature-sensitive protein Z (FtsZ), an important functional protein in the progression of cell division, has been widely reported and exploited as a target for creating antibacterial drugs in the field of medicine. Therefore, the fabrication of innovative frameworks targeting XooFtsZ may be an effective method for managing bacterial leaf blight diseases via blocking the binary division and reproduction of Xoo. As such, a series of novel N-(cinnamoyl)-N'-(substituted)acryloyl hydrazide derivatives containing pyridinium moieties were designed, and the anti-Xoo activity was determined. The bioassay results showed that compound A7 had excellent anti-Xoo activity (EC50 = 0.99 mg L-1) in vitro and distinct curative activity (63.2% at 200 mg L-1) in vivo. Further studies revealed that these designed compounds were XooFtsZ inhibitors, validating by the reduced GTPase activity of recombinant XooFtsZ, the nonfilamentous XooFtsZ assembly observed in the TEM images, and the prolonged Xoo cells from the fluorescence patterns. Computational docking studies showed that compound A7 had strong interactions with ASN34, GLN193, and GLN197 residues located in the α helix regions of XooFtsZ. The present study demonstrates the developed FtsZ inhibitors can serve as agents to control Xoo-induced infections.

9.
Life Sci ; 251: 117609, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32272180

RESUMO

AIMS: To identify the target of an adipose specific aptamer adipo-8, predict the potential interaction between adipo-8 and its target, and investigate lipid-lowering effect of adipo-8 in vitro and in vivo. MAIN METHODS: Distinct membranous protein of 3T3-L1 adipocyte pulled-down by adipo-8 was mass-spectrometry analyzed as target candidate(s), and affinity of adipo-8 to target protein-silent adipocyte was detected to validate it. Interaction between adipo-8 and target was predicted by bioinformatic analysis, further confirmed by aptamer truncation and competitive binding assay. To investigate lipid-lowering effect of adipo-8 and mechanism behind, 250 nmol/L adipo-8 or library was incubated with 3T3-L1 adipocyte or target-protein-silent adipocyte for 24 h, and 0.01 µg/g/day adipo-8 or library was administrated to high-fat-fed male mice for 21 days. KEY FINDINGS: APMAP (Adipocyte Plasma Membrane Associated Protein) was identified as adipo-8 target, and adipo-8 affinity to adipocytes was in proportional to APMAP expression. Docking model between the stem-loop structure of adipo-8 and APMAP were predicted that adipo-8 was likely to interact with APMAP at its amino-acid 275-411 sequence. Moreover, adipo-8 could ameliorate fat deposition through interaction with APMAP in vitro, and administration of adipo-8 in high-fat-diet fed mice resulted in body weight loss and blood triglyceride decrease without liver or renal dysfunction. SIGNIFICANCE: Adipo-8 could recognize APMAP specifically and interact with its targets to ameliorate fat deposition in vitro and in vivo. Aptamer adipo-8 has potential to act as an effective and safe targeted drug for obesity and obesity related diseases.


Assuntos
Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Aptâmeros de Nucleotídeos/metabolismo , Glicoproteínas de Membrana/metabolismo , Células 3T3-L1 , Animais , Dieta Hiperlipídica , Masculino , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular
10.
Life Sci ; 250: 117519, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32147429

RESUMO

OBJECTIVE: Papillary thyroid cancer (PTC) is the most ordinary type of thyroid cancer. Studies pivoting on the mechanisms of microRNAs (miRNAs) are adequately explored but not much on miR-448 in PTC. Thus, this study is proposed to bring forward the uncovered mechanisms of miR-448 in PTC. METHODS: Lysine specific demethylase 5B (KDM5B), miR-448 and transforming growth factor ß-induced factor 1 (TGIF1) expression in PTC tissues and cell lines were detected. The connection between miR-448 expression and clinicopathological characteristics of PTC patients was determined. PTC cell lines TPC-1 and K-1 were transfected with sh-KDM5B, si-TGIF1 or miR-448 mimic to explore their roles in PTC cell progression. Tumor xenografts in nude mice was performed to detect tumor volume and weight. RESULTS: KDM5B and TGIF1 were increased and miR-448 was declined in PTC tissues and cell lines. MiR-448 expression was connected with N stage, lymph node metastasis and advanced tumor node metastasis stage of PTC patients. KDM5B knockdown or TGIF1 reduction or miR-448 elevation undermined PTC cell progression and inhibited tumor growth of nude mice. Down-regulation of miR-448 followed by KDM5B knockdown reversed the effect of decreased KDM5B on the proliferation inhibition and apoptosis promotion of PTC cells. CONCLUSION: Our study elaborates that KDM5B-mediated miR-448 up-regulation restrains PTC cell progression and slows down tumor growth via TGIF1 repression, which provides a novel reference for treatment of PTC.


Assuntos
Carcinoma Papilar/metabolismo , Proteínas de Homeodomínio/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , MicroRNAs/genética , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Câncer Papilífero da Tireoide/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Idoso , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Metástase Linfática , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Metástase Neoplásica , Transplante de Neoplasias , Proteínas Nucleares/genética , Proteínas Repressoras/genética , Fator de Crescimento Transformador beta1/metabolismo , Regulação para Cima
11.
J Phys Chem Lett ; 11(6): 2150-2157, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32090570

RESUMO

Matchstick-like Ag2S-ZnS nanorods (NRs) with a tunable aspect ratio (AR) were synthesized using one-pot thermal decomposition. The ultraviolet photoelectron spectra and time-resolved photoluminescence spectra of the Ag2S-ZnS NRs were collected to study their electronic band structures and charge carrier dynamics. The energy difference (ΔE) at the interface between the ZnS stem and Ag2S tip was altered as the AR of Ag2S-ZnS NRs increased from 11.9 to 18.4, resulting in an enlarged driving force for the delocalized electrons along the conduction band of ZnS being injected into that of Ag2S. The interfacial electron transfer rate constant (ket) from ZnS to Ag2S could be enhanced by ∼2 orders of magnitude from 5.27 × 106 to 3.24 × 108 s-1, leading to a significant improvement in the efficiency of solar hydrogen generation. This investigation provides new physical insights into the manipulation of charge carrier dynamics by means of AR adjustment in semiconductor nanoheterostructures for photoelectric conversions.

12.
Bioorg Med Chem Lett ; 30(4): 126912, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31882301

RESUMO

In this letter, a variety of simple 6-chloro-4-(4-substituted piperazinyl)quinazoline derivatives was prepared. Preliminary bioassays revealed that these compounds showed good antibacterial activities toward phytopathogens Ralstonia solanacearum and Xanthomonas oryzae pv. oryzae (Xoo). Among these derivatives, compounds 5a, 5d, 5e, 5f, 5p, 5q, 6b, and 6d exhibited potent inhibition effects against R. solanacearum with EC50 within 4.60-9.94 µg/mL, especially, compound 5g exerted the strongest activity with EC50 of 2.72 µg/mL; compound 6b possessed the best inhibitory activity toward Xoo with EC50 of 8.46 µg/mL. Subsequently, a good predictive three-dimensional quantitative structure-activity relationship (3D-QSAR) model was constructed via CoMFA to direct the future structural modification and optimization. Furthermore, the pathogens' topological studies were performed to explore the possible antibacterial mechanism. Given their simple frameworks and facile synthesis, title compounds can serve as the potential antibacterial leads.

13.
Biomed Res Int ; 2019: 2187306, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31467874

RESUMO

Thrombin plays a pivotal role in the pathogenesis of atherosclerosis. Baicalin, an active flavonoid compound, was shown to attenuate the development of atherosclerosis, but the mechanism remains elusive. In the present study, the role and mechanism of baicalin in thrombin-induced cell injury was investigated in human umbilical vein endothelial cells (HUVECs). Our results showed that baicalin significantly reduced thrombin-induced apoptosis of HUVECs. Additional experiments showed that baicalin inhibited thrombin-induced NF-κB activation and PAR-1 expression. In addition, baicalin decreased thrombin-induced PAR-1 expression by inhibiting ERK pathway. These results indicated that baicalin has protective effects on thrombin-induced cell injury in HUVECs possibly through inhibition of PAR-1 expression and its downstream NF-κB activation, which was mediated by ERK1/2 activation.


Assuntos
Aterosclerose/tratamento farmacológico , Flavonoides/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Receptor PAR-1/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Aterosclerose/induzido quimicamente , Aterosclerose/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , NF-kappa B/genética , Substâncias Protetoras/farmacologia , Receptor PAR-1/genética , Trombina/toxicidade
14.
Anal Chem ; 91(13): 8289-8297, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31141341

RESUMO

Aptamers, short DNA or RNA oligonucleotides, which evolved from systematic evolution of ligands by exponential enrichment (SELEX), can perform specific target recognition. Papillary thyroid carcinoma (PTC) is of high incidence worldwide, and the prognosis of advanced PTC is poor. Up to now, there is no specific biomarker that can identify PTC and defects still remain in existing diagnostic methods. Here we report an aptamer, termed TC-6, which is generated from tissue-SELEX by using sections of papillary thyroid carcinoma and a normal thyroid gland. TC-6 could specifically target intracellular components of papillary thyroid cells with high affinity ( Kd = 57.66 ± 5.93 nmol/L) and have performed excellent biocompatibility both in vivo and in vitro. Moreover, fluorescence imaging of PTC tumor-bearing mice revealed that TC-6 was able to accumulate in tumor sites and could distinguish thyroid carcinoma from other benign thyroid diseases efficiently. In addition, TC-6d, a truncated aptamer of TC-6, maintained its affinity toward PTC with Kd of 39.20 ± 8.20 nmol/L. Overall, these results indicate that TC-6 is a potential candidate for developing novel tools for diagnosis and targeted therapy of PTC.


Assuntos
Aptâmeros de Nucleotídeos/farmacocinética , Técnica de Seleção de Aptâmeros/métodos , Câncer Papilífero da Tireoide/diagnóstico , Animais , Diagnóstico Diferencial , Humanos , Teste de Materiais , Camundongos , Imagem Óptica , Técnica de Seleção de Aptâmeros/normas , Câncer Papilífero da Tireoide/diagnóstico por imagem
15.
ACS Appl Mater Interfaces ; 11(8): 8126-8137, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30726054

RESUMO

Titanium dioxide (TiO2) nanorods (NRs) are widely used as photoanodes in photoelectrochemical (PEC) solar fuel production because of their remarkable photoactivity and stability. In addition, TiO2 NR electrode materials can be decorated with active CdS quantum dots (QDs) to expand the sunlight photon capture. The overall photoelectric conversion efficiency for TiO2 NR or QD-sensitized TiO2 NR electrode materials in PEC is typically dominated by their interfacial electron transfer (ET) properties. To understand the key factors affecting the ET, the anatase TiO2 seed layer was added into the interface between the rutile TiO2 NRs and fluorine-doped tin oxide (FTO) substrate. This seed layer enhanced the photocatalytic performance of both the TiO2 NR and CdS QD-sensitized TiO2 NR photoanodes in PEC. Time-resolved photoluminescence spectroscopy and PEC analyses, including Mott-Schottky, electrochemical impedance spectroscopy, and photovoltage ( Vph) measurements, were used to study the charge-carrier dynamics at the interfaces between the FTO, TiO2, and CdS QD. Analysis of the results showed that band alignment at the anatase/rutile junction between the TiO2 and FTO promoted electron-collection efficiency ( eEC) at the FTO/TiO2 interface and ET rate constant ( kET) at the TiO2/CdS QD interface. Furthermore, 34% enhancement of the efficiency in hydrogen (H2) generation demonstrated the potential of the TiO2 seed-layer-mediated TiO2/CdS QD NR photoanode in the application of PEC solar fuel production. The current work represents new insights into the mechanism of ET in TiO2 and TiO2/CdS QD NR, which is very useful for the development of photoelectrode materials in solar energy conversions.

16.
Sci Rep ; 7(1): 7179, 2017 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-28775305

RESUMO

Excessive secretion of glucagon, a functional insulin antagonist, significantly contributes to hyperglycemia. Glucagon exerts its physiological functions through activation of the glucagon receptor (GCGR). Inhibition of GCGR activity represents a potential therapeutic approach for reducing excess glucose production in diabetes mellitus. Aptamers are short DNA or RNA oligonucleotides evolved from systematic evolution of ligands by exponential enrichment (SELEX). Here, we have successfully selected a DNA aptamer against GCGR by cell-SELEX, which can specifically bind membrane protein of CHO-GCGR cells with a K d of 52.7 ± 5.1 nM. Aptamer-mediated pull-down and gcgr knockdown assay verified that GCGR was the target of aptamer GR-3. Binding analysis revealed that GR-3 could recognize other cells with different affinity according to the level of GCGR protein expressed in these cells. Hepatic tissue imaging suggested that GR-3 could bind the cell membrane of hepatic tissues. With the advantages of small size, high binding affinity, good stability, lack of immunogenicity, and easy synthesis, aptamer GR-3 against GCGR can be a promising tool with the potential to attenuate hyperglycemia in diabetes mellitus.


Assuntos
Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/síntese química , Receptores de Glucagon/antagonistas & inibidores , Animais , Aptâmeros de Nucleotídeos/farmacologia , Células CHO , Cricetulus , Glucagon/antagonistas & inibidores , Glucagon/metabolismo , Fígado/metabolismo , Camundongos , Receptores de Glucagon/metabolismo , Técnica de Seleção de Aptâmeros/métodos
17.
Ultrason Sonochem ; 38: 9-18, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28633861

RESUMO

This study investigated for the first time the feasibility of using a magnetic field for sludge disintegration. Approximately 41.01% disintegration degree (DD) was reached after 30min at 180mT magnetic field intensity upon separate magnetic field treatment. Protein and polysaccharide contents significantly increased. This test was optimized using a Box-Behnken design (BBD) with response surface methodology (RSM) to fit the multiple equation of the DD. The maximum DD was 43.75% and the protein and polysaccharide contents increased to 56.71 and 119.44mg/L, respectively, when the magnetic field strength was 119.69mT, reaction time was 30.49min, and pH was 9.82 in the optimization experiment. We then analyzed the effects of ultrasound alone. We are the first to combine magnetic field with ultrasound to disintegrate waste-activated sludge (WAS). The optimum effect was obtained with the application of ultrasound alone at 45kHz frequency, with a DD of about 58.09%. By contrast, 62.62% DD was reached in combined magnetic field and ultrasound treatment. This combined test was also optimized using BBD with RSM to fit the multiple equation of DD. The maximum DD of 64.59% was achieved when the magnetic field intensity was 197.87mT, ultrasonic frequency was 42.28kHz, reaction time was 33.96min, and pH was 8.90. These results were consistent with those of particle size and electron microscopy analyses. This research proved that a magnetic field can effectively disintegrate WAS and can be combined with other physical techniques such as ultrasound for optimal results.


Assuntos
Campos Magnéticos , Esgotos , Sonicação , Gerenciamento de Resíduos/métodos , Concentração de Íons de Hidrogênio , Fatores de Tempo
18.
Artigo em Inglês | MEDLINE | ID: mdl-27800663

RESUMO

A key goal of modern medicine is target-specific therapeutic intervention. However, most drugs lack selectivity, resulting in 'off-target' side effects. To address the requirements of 'targeted therapy,' aptamers, which are artificial oligonucleotides, have been used as novel targeting ligands to construct aptamer drug conjugates (ApDC) that can specifically bind to a broad spectrum of targets, including diseased cells. Accordingly, the application of aptamers in targeted drug delivery has attracted broad interest due to their impressive selectivity and affinity, low immunogenicity, easy synthesis with high reproducibility, facile modification, and relatively rapid tissue penetration with no toxicity. Functionally, aptamers themselves can be used as macromolecular drugs, and they are also commonly used in biomarker discovery and targeted drug delivery. In this review, we will highlight the most recent advances in the development of aptamers and aptamer conjugates, and discuss their potential in targeted therapy. WIREs Nanomed Nanobiotechnol 2017, 9:e1438. doi: 10.1002/wnan.1438 For further resources related to this article, please visit the WIREs website.


Assuntos
Aptâmeros de Nucleotídeos , Portadores de Fármacos , Sistemas de Liberação de Medicamentos/métodos , Animais , Pesquisa Biomédica , Linhagem Celular , Humanos , Camundongos
19.
Springerplus ; 5(1): 1809, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27818858

RESUMO

PURPOSE: The prognosis for recipients with hepatocellular carcinoma (HCC) of salvage liver transplantation (SLT) versus those of primary liver transplantation (PLT) remains controversial. The objective of this study was to evaluate the clinical features and survival rate of SLT recipients. METHODS: Three hundred seventy-one patients with HCC transplanted at Shanghai General Hospital, China, between October 2001 and October 2011 were separated into PLT (n = 295) and SLT (n = 76) groups. Patient characteristics and survival curves were studied by univariate and multivariate analysis. A Milan criteria-stratified survival analysis was conducted. RESULTS: The proportions of reoperation (11.8 vs. 5.4 %, P = 0.047) and early postoperative mortality (11.8 vs. 4.7 %, P = 0.032) were higher in the SLT group than in the PLT group. Recurrence free survival (RFS) rate and overall survival (OS) rate had no statistically significant differences after stratification using Milan criteria between the PLT group and SLT group. Alphafetoprotein >400 ng/mL (P = 0.011), microscopic vascular invasion (MVI) (P < 0.001), tumor node metastasis (TNM) staging (P = 0.006), and out of Milan criteria (P < 0.001) were independent risk factors for RFS, while MVI (P < 0.001), TNM staging (P = 0.009), and out of Milan criteria (P = 0.003) were factors for OS. In the multivariate logistic regression analysis, HCC recurrence was associated with MVI (OR = 4.196 [2.538-6.936], P < 0.001), and out of Milan criteria (OR = 2.704 [1.643-4.451], P < 0.001). CONCLUSIONS: Our retrospective, single-center study demonstrated that SLT increases surgical difficulty; however, it has good post-transplantation OS and is a feasible alternative after HCC recurrence within Milan criteria.

20.
Phys Chem Chem Phys ; 18(46): 31828-31835, 2016 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-27841403

RESUMO

In this study, we report anomalous size-dependent photoluminescence (PL) intensity variation of PbS quantum dots (QDs) with the formation of a thin CdS shell via a microwave-assisted cation exchange approach. Thin shell formation has been established as an effective strategy for increasing the PL of QDs. Nonetheless, herein we observed an unusual PL decrease in ultrasmall QDs upon shell formation. We attempted to understand this abnormal phenomenon from the perspective of trap density variation and the probability of electrons and holes reaching surface defects. To this end, the quantum yield (QY) and PL lifetime (on the ns-µs time scales) of pristine PbS QDs and PbS/CdS core/shell QDs were measured and the radiative and non-radiative recombination rates were derived and compared. Moreover, transient absorption (TA) analysis (on the fs-ns time scale) was performed to better understand exciton dynamics at early times that lead to and affect longer time dynamics and optical properties such as PL. These experimental results, in conjunction with theoretical calculations of electron and hole wave functions, provide a complete picture of the photophysics governing the core/shell system. A model was proposed to explain the size-dependent optical and dynamic properties observed.

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