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1.
ACS Appl Mater Interfaces ; 15(38): 44962-44973, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37713588

RESUMO

Solid-state lithium batteries (SSBs) have been widely researched as next-generation energy storage technologies due to their high energy density and high safety. However, lithium dendrite growth through the solid electrolyte usually results from the catastrophic interface contact between the solid electrolyte and lithium metal. Herein, a gradient nitrogen-doping strategy by nitrogen plasma is introduced to modify the surface and subsurface of the garnet electrolyte, which not only etches the surface impurities (e.g., Li2CO3) but also generates an in situ formed Li3N-rich interphase between the solid electrolyte and lithium anode. As a result, the Li/LLZTON-3/Li cells show a low interfacial resistance (3.50 Ω cm2) with a critical current density of about 0.65 mA cm-2 at room temperature and 1.60 mA cm-2 at 60 °C, as well as a stable cycling life for over 1300 h at 0.4 mA cm-2 at room temperature. A hybrid solid-state full cell paired with a LiFePO4 cathode exhibits excellent cycling durability and rate performance at room temperature. These results demonstrate a rational strategy to enable lithium utilization in SSBs.

2.
Adv Mater ; 35(2): e2200538, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35962983

RESUMO

As the world steps into the era of Internet of Things (IoT), numerous miniaturized electronic devices requiring autonomous micropower sources will be connected to the internet. All-solid-state thin-film lithium/lithium-ion microbatteries (TFBs) combining solid-state battery architecture and thin-film manufacturing are regarded as ideal on-chip power sources for IoT-enabled microelectronic devices. However, unlike commercialized lithium-ion batteries, TFBs are still in the immature state, and new advances in materials, manufacturing, and structure are required to improve their performance. In this review, the current status and existing challenges of TFBs for practical application in internet-connected devices for the IoT are discussed. Recent progress in thin-film deposition, electrode and electrolyte materials, interface modification, and 3D architecture design is comprehensively summarized and discussed, with emphasis on state-of-the-art strategies to improve the areal capacity and cycling stability of TFBs. Moreover, to be suitable power sources for IoT devices, the design of next-generation TFBs should consider multiple functionalities, including wide working temperature range, good flexibility, high transparency, and integration with energy-harvesting systems. Perspectives on designing practically accessible TFBs are provided, which may guide the future development of reliable power sources for IoT devices.

3.
Int J Mol Sci ; 23(21)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36361684

RESUMO

The low response rates associated with immune checkpoint inhibitor (ICI) use has led to a surge in research investigating adjuvant combination strategies in an attempt to enhance efficacy. Repurposing existing drugs as adjuvants accelerates the pace of cancer immune therapy research; however, many combinations exacerbate the immunogenic response elicited by ICIs and can lead to adverse immune-related events. Metformin, a widely used type 2 diabetes drug is an ideal candidate to repurpose as it has a good safety profile and studies suggest that metformin can modulate the tumour microenvironment, promoting a favourable environment for T cell activation but has no direct action on T cell activation on its own. In the current study we used PET imaging with [18F]AlF-NOTA-KCNA3P, a radiopharmaceutical specifically targeting KV1.3 the potassium channel over-expressed on active effector memory T-cells, to determine whether combining PD1 with metformin leads to an enhanced immunological memory response in a preclinical colorectal cancer model. Flow cytometry was used to assess which immune cell populations infiltrate the tumours in response to the treatment combination. Imaging with [18F]AlF-NOTA-KCNA3P demonstrated that adjuvant metformin significantly improved anti-PD1 efficacy and led to a robust anti-tumour immunological memory response in a syngeneic colon cancer model through changes in tumour infiltrating effector memory T-cells.


Assuntos
Diabetes Mellitus Tipo 2 , Metformina , Neoplasias , Humanos , Metformina/farmacologia , Metformina/uso terapêutico , Células T de Memória , Microambiente Tumoral , Neoplasias/tratamento farmacológico , Adjuvantes Imunológicos/uso terapêutico
4.
Ther Adv Respir Dis ; 15: 17534666211009407, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33888007

RESUMO

BACKGROUND AND AIMS: The application of prone positioning with acute hypoxemic respiratory failure (AHRF) or acute respiratory distress syndrome (ARDS) in non-intubation patients is increasing gradually, applying prone positioning for more high-flow nasal oxygen therapy (HFNC) and non-invasive ventilation (NIV) patients. This meta-analysis evaluates the efficacy and tolerance of prone positioning combined with non-invasive respiratory support in patients with AHRF or ARDS. METHODS: We searched randomized controlled trials (RCTs) (prospective or retrospective cohort studies, RCTs and case series) published in PubMed, EMBASE and the Cochrane Central Register of Controlled Trials from 1 January 2000 to 1 July 2020. We included studies that compared prone and supine positioning with non-invasive respiratory support in awake patients with AHRF or ARDS. The meta-analyses used random effects models. The methodological quality of the RCTs was evaluated using the Newcastle-Ottawa quality assessment scale. RESULTS: A total of 16 studies fulfilled selection criteria and included 243 patients. The aggregated intubation rate and mortality rate were 33% [95% confidence interval (CI): 0.26-0.42, I2 = 25%], 4% (95% CI: 0.01-0.07, I2 = 0%), respectively, and the intolerance rate was 7% (95% CI: 0.01-0.12, I2 = 5%). Prone positioning increased PaO2/FiO2 [mean difference (MD) = 47.89, 95% CI: 28.12-67.66; p < 0.00001, I2 = 67%] and SpO2 (MD = 4.58, 95% CI: 1.35-7.80, p = 0.005, I2 = 97%), whereas it reduced respiratory rate (MD = -5.01, 95% CI: -8.49 to -1.52, p = 0.005, I2 = 85%). Subgroup analyses demonstrated that the intubation rate of shorter duration prone (⩽5 h/day) and longer duration prone (>5 h/day) were 34% and 21%, respectively; and the mortality rate of shorter duration prone (⩽5 h/day) and longer duration prone (>5 h/day) were 6% and 0%, respectively. PaO2/FiO2 and SpO2 were significantly improved in COVID-19 patients and non-COVID-19 patients. CONCLUSION: Prone positioning could improve the oxygenation and reduce respiratory rate in both COVID-19 patients and non-COVID-19 patients with non-intubated AHRF or ARDS.The reviews of this paper are available via the supplemental material section.


Assuntos
COVID-19/complicações , Posicionamento do Paciente , Síndrome do Desconforto Respiratório/terapia , Insuficiência Respiratória/terapia , SARS-CoV-2 , COVID-19/mortalidade , Humanos , Intubação Intratraqueal , Oxigênio/sangue , Decúbito Ventral , Respiração
5.
Adv Mater ; 33(5): e2003524, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33336535

RESUMO

All-solid-state thin film lithium batteries (TFBs) are proposed as the ideal power sources for microelectronic devices. However, the high-temperature (>500 °C) annealing process of cathode films, such as LiCoO2 and LiMn2 O4, restricts the on-chip integration and potential applications of TFBs. Herein, tunnel structured Lix MnO2 nanosheet arrays are fabricated as 3D cathode for TFBs by a facile electrolyte Li+ ion infusion method at very low temperature of 180 °C. Featuring an interesting tunnel intergrowth structure consisting of alternating 1 × 3 and 1 × 2 tunnels, the Lix MnO2 cathode shows high specific capacity with good structural stability between 2.0 and 4.3 V (vs. Li+ /Li). By utilizing the 3D Lix MnO2 cathode, all-solid-state Lix MnO2 /LiPON/Li TFB (3DLMO-TFB) has been successfully constructed with prominent advantages of greatly enriched cathode/electrolyte interface and shortened Li+ diffusion length in the 3D structure. Consequently, the 3DLMO-TFB device exhibits large specific capacity (185 mAh g-1 at 50 mA g-1 ), good rate performance, and excellent cycle performance (81.3% capacity retention after 1000 cycles), outperforming the TFBs using spinel LiMn2 O4 thin film cathodes fabricated at high temperature. Importantly, the low-temperature preparation of high-performance cathode film enables the fabrication of TFBs on various rigid and flexible substrates, which could greatly expand their potential applications in microelectronics.

6.
Nanotechnology ; 31(18): 185402, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31952062

RESUMO

SnO2/α-Fe2O3 hybrid nanofibers, consisting of one dimensional hollow SnO2 nanotubes decorated with Fe2O3 particles, are synthesized via a facile electrospinning process followed by a hydrothermal treatment and investigated as the anode material for lithium-ion batteries. The SnO2/Fe2O3 hybrid nanofibers not only provide a large surface area for lithium storage sites, but also show the capability of fast charge transport for both electrons and lithium ions. Both SnO2 and Fe2O3 contribute to the lithium storage and the hybrid structure exhibits a synergistic effect when participating in electrochemical reactions. With the smart structure design, the hybrid SnO2/Fe2O3 nanofiber electrode shows superior electrochemical performance compared to the bare SnO2 nanofiber electrode. In addition to a large first-cycle discharge capacity up to 1105 mAh g-1, the hybrid SnO2/Fe2O3 nanofibers electrode also exhibits good cycling stability and high rate capability.

7.
Small ; 14(52): e1804149, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30467972

RESUMO

3D all-solid-state thin film batteries (TFBs) are proposed as an attractive power solution for microelectronics. However, the challenge in fabricating self-supported 3D cathodes constrains the progress in developing 3D TFBs. In this work, 3D LiMn2 O4 (LMO) nanowall arrays are directly deposited on conductive substrates by magnetron sputtering via controlling the thin film growth mode. 3D TFBs based on the 3D LMO nanowall arrays and 2D TFBs based on the planar LMO thin films are successfully fabricated using a lithium phosphorous oxynitride (LiPON) electrolyte and Li anode. In comparison, the 3D TFB significantly outperforms the 2D TFB, exhibiting large specific capacity (121 mAh g-1 at 1 C), superior rate capability (83 mAh g-1 at 20 C), and good cycle performance (over 90% capacity retention after 500 cycles). The superior electrochemical performance of the 3D TFB can be attributed to the 3D architecture, which not only greatly increases the cathode/electrolyte interface and shortens the Li+ diffusion length, but also effectively enhances the structural stability. Importantly, the vertically aligned nanowall array architecture of the cathode can significantly mitigate disordered LMO formation at the cathode surface compared to the 2D planar thin film, resulting in a greatly reduced interface resistance and improved rate performance.

8.
Biomed Pharmacother ; 97: 1564-1574, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29793319

RESUMO

Malignant glioma are linked to a high mortality rate. Therefore, it is necessary to explore and develop effective therapeutic strategy. Oroxyloside is a metabolite of oroxylin A. However, its inhibitory effects on cancer are little to be known. In the present study, we investigated the effects of oroxyloside on cell proliferation, migration, and apoptosis in vitro and in vivo in human glioma. The results indicated that oroxyloside significantly suppressed the proliferation of human glioma cells through inducing cell cycle arrest at G0/G1 phase through reducing Cyclin D1 and cyclin-dependent kinase 2 (CDK2) while enhancing p53 and p21 expressions. In addition, the migration of glioma cells was dramatically inhibited by oroxyloside in a dose-dependent manner, which was related to its modulation on extracellular matrix (ECM), as evidenced by up-regulated E-cadherin, and metastasis-associated protein 3 (MTA3), whereas down-regulated N-cadherin, Vimentin, Twist, alpha-smooth muscle actin (α-SMA) and Syndecan-2. Furthermore, oroxyloside treatment markedly induced apoptosis in glioma cells through improving Caspase-9, Caspase-3 and PARP cleavage, accompanied with high release of cytochrome c (Cyto-c) into cytoplasm and subsequently increase of apoptotic protease-activating factor 1 (Apaf-1). In vivo, oroxyloside administration significantly inhibited the glioma cell xenograft tumorigenesis through various signaling pathways, including suppression of Cyclin D1/CDK2 and ECM pathways, as well as potentiation of p53/p21 and Caspases pathways. Together, the findings above illustrated that oroxyloside, for the first time, was used as a promising candidate against human glioma.


Assuntos
Apoptose , Progressão da Doença , Flavonas/uso terapêutico , Glioma/tratamento farmacológico , Glioma/patologia , Glucuronídeos/uso terapêutico , Transdução de Sinais , Animais , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Citocromos c/metabolismo , Flavonas/farmacologia , Glucuronídeos/farmacologia , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
9.
BMC Cancer ; 18(1): 148, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29409466

RESUMO

BACKGROUND: Although EGFR-TKI is the preferred treatment for NSCLC patients with sensitive mutations, subsequent drug resistance is almost inevitable. The specific mechanisms of EGFR-TKI drug resistance can be identified through repeat biopsy. METHODS: To better understand the clinical characteristics of TKI resistance in NSCLC patients, we retrospectively reviewed studies of acquired TKI drug resistance using repeat biopsy from the last decade. The relevant literature was retrieved from January 2005 to August 2015 in the databases Medline and Embase. The search terms were NSCLC or non-small cell lung cancer and T790 M. RESULTS: A total of 478 patients with NSCLC tested by repeated biopsy were confirmed to have acquired TKI resistance. Analysis indicated that 240 patients (50.21%) of the 478 patients with acquired TKI drug resistance had the T790 M mutation. The detection rate of T790 M in different repeat biopsy sites was also different, with the highest positive rate in the lymph nodes (60%) and the lowest detection rate in cerebrospinal fluid (less than 5%). In addition, patients with T790 M had longer overall survival compared to those without the mutation (P < 0.05). Of the 240 patients with T790 M mutations, 213 patients showed results consistent with the mutation analysis before TKI treatment, and the rate of patients with the L858R point mutation along with the T790 M mutation was lower than that of patients with the exon 19 deletion (36.42% to 58.30%). CONCLUSIONS: T790 M occurred more frequently in patients with the exon 19 deletion than in those with exon 21 L858R, which gave the survival benefit of the T790 M mutation and may explain why patients with the exon 19 deletion had an improved overall survival.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Neoplasias Pulmonares/tratamento farmacológico , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/genética , Éxons/genética , Frequência do Gene , Humanos , Neoplasias Pulmonares/genética , Análise de Sobrevida
10.
Biomed Pharmacother ; 95: 1607-1618, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28950661

RESUMO

Tumor necrosis factor-related apoptosis-induced ligand (TRAIL) is reported as a promising anti-cancer therapeutic agent. Nevertheless, a variety of cancer cells, including human malignant glioma cells, are resistant to TRAIL treatment, indicating that it is necessary to find effective strategies to overcome the TRAIL resistance. Linarin (LIN), a natural flavonoid compound in Flos Chrysanthemi Indici (FCI), has been exhibited to exert various pharmacological activities, including anti-cancer. Here in our study, we found that non-cytotoxic doses of LIN (5µM) dramatically potentiated TRAIL (80ng/ml)-induced cytotoxicity (52.36±1.58%) and apoptosis (68.50±1.23%) using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and flow cytometry assays, respectively, in human glioma cells of U87MG. Apoptosis was evidenced by enhanced cleavage of Caspase-8/-9/-3 and poly (ADP-ribose) polymerase (PARP), and reduced anti-apoptotic proteins, including B-cell leukemia/lymphoma 2 (Bcl-2), mantle cell lymphoma (Mcl)-1, and Survivin. Moreover, both intrinsic and extrinsic apoptosis pathways were included in apoptosis induced by LIN and TRAIL co-treatment, along with high release of Cyto-c into cytoplasm and enhancement of fas-associated protein with death domain (FADD), death-inducing signaling complex (DISC), death receptor 4 (DR) 4 and DR5, respectively. Reactive oxygen species (ROS) generation, up to 39.86±2.32%, was also highly triggered by TRAIL and LIN combinational treatment, which was accompanied with high phosphorylation of c-Jun-N-terminal kinase (JNK). In vivo, TRAIL and LIN double treatment significantly reduced the tumor growth using xenograft tumor model through inducing apoptosis. We demonstrated that combining LIN with TRAIL treatments might be effective against TRAIL-resistant glioma cells through inducing apoptosis regulated by ROS generation.


Assuntos
Apoptose/efeitos dos fármacos , Glioma/tratamento farmacológico , Glicosídeos/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Linhagem Celular Tumoral , Chrysanthemum/química , Citometria de Fluxo , Glioma/patologia , Glicosídeos/administração & dosagem , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Espécies Reativas de Oxigênio/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Sci Rep ; 7(1): 4088, 2017 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-28642543

RESUMO

This study evaluates the relationship between obstructive sleep apnea (OSA) and asthma. Literature search was carried out in several electronic databases and random effects meta-analyses were performed to obtain pooled estimates of the prevalence of OSA, OSA risk and sleep disordered breathing (SDB) in asthma patients and pooled odds ratios of the prevalence between asthma and non-asthma patients. In adult asthma patients, the prevalence [95% confidence interval] of OSA, OSA risk, and SDB was 49.50 [36.39, 62.60] %, 27.50 [19.31, 35.69] %, and 19.65 [14.84, 24.46] % respectively. The odds of having OSA, OS risk and SDB by the asthma patients were 2.64 [1.76, 3.52], 3.73 [2.90, 4.57] and 1.73 [1.11, 2.36] times higher (p < 0.00001 for all) in asthma than in non-asthma patients, respectively. Adult asthma patients with OSA had significantly higher BMI in comparison with asthma patients without OSA. This study reveals that the prevalence of OSA in asthma patients is considerably higher; even higher than OSA risk and SDB. Sleep studies should be performed in asthma patients with symptoms suggestive of OSA/OSA risk/SDB.


Assuntos
Asma/complicações , Asma/epidemiologia , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/epidemiologia , Adulto , Fatores Etários , Índice de Massa Corporal , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Fatores de Risco
12.
Huan Jing Ke Xue ; 34(6): 2256-62, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-23947041

RESUMO

In this study, we present a nanofiltration (NF90, NF270) pretreatment to increase the precision of dissolved organic nitrogen (DON) measurements in water samples. The variations of DON measurements with and without NF pretreatment were investigated. And the effects on the removal of dissolved inorganic nitrogen (DIN) by NF90 and NF270 were compared. As shown in the results, the average removal rates reached 30.7%, 55.9% of NH4(+)-N, 50.0%, 73.1% of NO3(-) -N and 42.9%, 72.0% of NO2(-)-N for NF90 and NF270 pretreatment, respectively. NF270 was obviously more effective to remove the DIN species. Concentrations of DON measured using traditional methods varied from 0.09 to 0.46 mg x L(-1), with negative concentration (-0.08 mg x L(-1)) at site 2 and the DIN/TDN ratio ranged from 85.3% to 105%; while the concentrations of DON measurements varied from 0.03 to 0.58 mg x L(-1), and the DIN/TDN ratio ranged from 76.1% to 90.6% for NF90 pretreatment and varied from 0.10 to 0.59 mg x L(-1), and the DIN/TDN ratio ranged from 47.5% to 84.5% for NF270 pretreatment. The results indicated that nanofiltration pretreatment could effectively remove the DIN species, decrease the standard deviation of DON measurements and increase the precision of DON measurements. The distribution of DON in water samples of Beijing Olympic Forest Park was investigated. The results showed that there was seasonal variation in the concentrations of DON in landscape water from the Olympic Forest Park. And there was significant difference between the north and south part. The DON concentrations were less than 0.2 mg x L(-1) in November, March and May and higher in July in the north part, while the DON concentrations were lower in May and higher in November and March in the south part, ranging from 0.40-0.65 mg x L(-1).


Assuntos
Água Doce/química , Nanotecnologia/métodos , Nitrogênio/análise , Compostos Orgânicos/análise , Filtração/métodos , Estações do Ano , Solubilidade
13.
Luminescence ; 28(3): 392-400, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22696455

RESUMO

In this study, we report for the first time a one-pot approach for the synthesis of new CdSeTeS quaternary-alloyed quantum dots (QDs) in aqueous phase by microwave irradiation. CdCl2 was used as a Cd precursor during synthesis, NaHTe and NaHSe were used as Te and Se precursors and mercaptopropionic acid (MPA) was used as a stabilizer and source of sulfur. A series of quaternary-alloyed QDs of different sizes were prepared. CdSeTeS QDs exhibited a wide emission range from 549 to 709 nm and high quantum yield (QY) up to 57.7 %. Most importantly, the quaternary-alloyed QDs possessed significantly long fluorescence lifetimes > 100 ns as well as excellent photostability. Results of high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray spectroscopy (EDX) and powder X-ray diffraction (XRD) spectroscopy showed that the nanocrystals possessed a quaternary alloy structure with good crystallinity. Fluorescence correlation spectroscopy (FCS) showed that QDs possessed good water solubility and monodispersity in aqueous solution. Furthermore, CdSeTeS QDs were modified with alpha-thio-omega-carboxy poly(ethylene glycol) (HS-PEG-COOH) and the modified QDs were linked to anti-epidermal growth factor receptor (EGFR) antibodies. QDs with the EGFR antibodies as labeling probes were successfully applied to targeted imaging for EGFR on the surface of SiHa cervical cancer cells. We believe that CdSeTeS QDs can become useful probes for in vivo targeted imaging and clinical diagnosis.


Assuntos
Ligas/química , Neoplasias/química , Pontos Quânticos/química , Ligas/síntese química , Linhagem Celular Tumoral , Humanos , Micro-Ondas , Neoplasias/diagnóstico , Espectrometria por Raios X , Difração de Raios X
14.
Electrophoresis ; 33(13): 1987-95, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22806464

RESUMO

In this paper, we systematically investigated the conjugation of quantum dots (QDs) with certain biomolecules using capillary electrophoresis (CE) and fluorescence correlation spectroscopy (FCS) methods. Commercial QDs and aqueous-synthesized QDs in our lab were used as labeling probes, certain bio-macromolecules, such as proteins, antibodies, and enzymes, were used as mode samples, and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) and N-hydroxysulfo-succinimide (Sulfo-NHS) were used as linking reagents. We studied the effects of certain factors such as the isoelectric points (pIs) of bio-macromolecules and buffer pH on the bioconjugation of QDs, and found that the pIs of bio-macromolecules played an important role in the conjugation reaction. By the optimization of the buffer pH some proteins with different pIs were efficiently conjugated with QDs using EDC and Sulfo-NHS as linking agents. Furthermore, we on-line investigated the kinetic process of QDs-bioconjugation by FCS and found that the conjugation reaction of QDs with protein was rapid and the reaction process almost completed within 10 min. We also observed that QDs conjugated with proteins were stable for at least 5 days in phosphate buffer. Our work described here will be very helpful for the improvement of the QDs conjugation efficiency in bioapplications.


Assuntos
Eletroforese Capilar/métodos , Nanoconjugados/química , Proteínas/química , Pontos Quânticos , Espectrometria de Fluorescência/métodos , Animais , Anticorpos/química , Soluções Tampão , Enzimas/química , Humanos , Ponto Isoelétrico , Cinética , Camundongos
15.
Langmuir ; 28(9): 4464-71, 2012 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-22276658

RESUMO

Gold nanoparticles (GNPs) are attractive alternative optical probes and good biocompatible materials due to their special physical and chemical properties. However, GNPs have a tendency to aggregate particularly in the presence of high salts and certain biological molecules such as nucleic acids and proteins. How to improve the stability of GNPs and their bioconjugates in aqueous solution is a critical issue in bioapplications. In this study, we first synthesized 17 nm GNPs in aqueous solution and then modified them with six thiol compounds, including glutathione, mercaptopropionic acid (MPA), cysteine, cystamine, dihydrolipoic acid, and thiol-ending polyethylene glycol (PEG-SH), via a Au-S bond. We systematically investigated the effects of the thiol ligands, buffer pH, and salt concentrations of the solutions on the colloidal stability of GNPs using UV-vis absorption spectroscopy. We found that GNPs modified with PEG-SH were the most stable in aqueous solution compared to other thiol compounds. On the basis of the above results, we developed a simple and efficient approach for modification of GNPs using a mixture of PEG-SH and MPA as ligands. These biligand-modified GNPs were facilely conjugated to antibody using 1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide and N-hydroxysulfosuccinimide as linkage reagents. We conjugated GNPs to epidermal growth factor receptor antibodies and successfully used the antibody-GNP conjugates as targeting probes for imaging of cancer cells using the illumination of a dark field. Compared to current methods for modification and conjugation of GNPs, our method described here is simple, has a low cost, and has potential applications in bioassays and cancer diagnostics and studies.


Assuntos
Coloides/química , Diagnóstico por Imagem/métodos , Ouro/química , Nanopartículas Metálicas/química , Nanotecnologia/métodos , Cistamina/química , Cisteína/química , Glutationa/química , Humanos , Ácido Tióctico/análogos & derivados , Ácido Tióctico/química
16.
Huan Jing Ke Xue ; 32(4): 1000-7, 2011 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-21717739

RESUMO

In this study, the characteristics of organic phosphorus fractions in sediments of seven lakes with different drainage basin feature, ecological structure, and polluted levels from different regions were investigated, and the relationships between organic phosphorus (Po), inorganic phosphorus (Pi) and bioavailable characters were also discussed. The difference of the related content of Po in different sediments indicated the discrepancy of phosphorus sources and biogeochemical cycles in different lakes. Organic matter (OM) was significantly correlated with Po (R2 = 0.80, p < 0.01), and except for Lake Qilu, OM was significantly correlated with labile Po, moderately labile Po and nonlabile Po in all studied sediments (R2 were 0.85, 0.52, 0.80 respectively, p < 0.01). The moderately labile Po and nonlabile Po were the main fraction of Po in all studied lakes, and the relative contributions to total Po were 15.12%-66.73% and 27.99%-77.72%, respectively. The mean proportion of labile Po was 6.1% in studied sediments. The rank order of Po fractions was residual Po > HCl-Po > fulvic acid-Po > humic acid-Po > NaHCO3-Po with mean relative proportion 8.3:3.1:2.2:1.8:1.0. Labile Po was significantly correlated with total phosphorus (TP), Pi , Po, NaHCO3-Pi and NaOH-Pi . Furthermore, Labile Po was also significantly correlated with T), Po and NaOH-Pi in all studied sediments, which suggested that labile Po was transformed into bioavailable phosphorus and the nonlabile Po may become a potential source of available phosphorus, although it was considered as highly resistant fraction.


Assuntos
Eutrofização , Sedimentos Geológicos/análise , Organofosfatos/química , Poluentes Químicos da Água/análise , China , Ecossistema , Lagos/análise , Compostos Orgânicos/análise , Compostos Orgânicos/química , Organofosfatos/análise
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(1): 105-8, 2011 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-21428067

RESUMO

The near infrared reflectance spectra (NIRS) of interstitial water samples of lake sediments in Chaohu lake were determined by near-infrared reflectance spectrometry. The respective near NIRS calibration models for predicting total nitrogen (TN), total organic carbon (TOC), phosphorus ( PO3(3-)), ammonia nitrogen(NH3-N) and silicate (SiO3-) were built using partial least squares (PLS) algorithm with two spectral pretreatment tools including, wavelet compression combining orthogonal signal correction (OSC) and orthogonal signal correction (OSC) combining wavelet compression. The correlation coefficients between measured values and predicted values in calibration set for TN, NH3-N, PO3(3-), TOC and SiO3(3-) were 0.975, 0.989, 0.937, 0.862 and 0.888, respectively. RMSEC (root mean square error of the calibration) for TN, NH3-N, PO3(3-), TOC and SiO3- were 0.353, 0.238, 0.031 3, 2.005 and 2.674 mg x L(-1), respectively. The correlation coefficients between measured values and predicted values in validation set for TN, NH3-N, PO3(3-), TOC and SiO3- were 0.912, 0.918, 0.773, 0.337 and 0. 856, respectively. RMSEP(root mean square error of the prediction)for TN, NH3-N, PO3(3-), TOC and SiO3- were 1.424, 0.945, 0.081, 7.866 and 4.273 mg x L(-1), respectively.

18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(10): 2624-7, 2010 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-21137386

RESUMO

The lake sediments record important environmental evolution information of lake in recent 100 years. However, a rapid and precise combination analytical method measuring nutrient components in lake sediments can not be established. The near infrared reflectance spectra (NIRS) of sediment coring samples were determined by near-infrared reflectance spectrometry. The respective near NIRS calibration models for predicting total carbon (TC), total nitrogen (TN), total organic carbon (TOC) and total phosphorus (TP) were built first in China using partial least squares (PLS) algorithm with six spectral pretreatment tools including first-order derivate, wavelet denoise, orthogonal signal correction (OSC), wavelet denoise combining orthogonal signal correction (OSC), first-order derivate combining orthogonal signal correction (OSC), and orthogonal signal correction (OSC) combining wavelet compression. The results showed that although NIR all calibration models can not well predict TOC, the first-order derivate combining OSC spectral calibration model had a good prediction for TC and TN, and for TP OSC spectral calibration model was good. The correlation coefficients between measuring values and predicted values in validation set for TC, TN and TP were 0.76, 0.87 and 0.81, respectively. RMSEP (Root mean square error of the prediction) for TC, TN and TP were 0.13%, 0.0082% and 0.012%, respectively. The study has an important significance of driving the domestic researches on spectroscopy characteristic of lake sediments and establishment of rapid analytical technique determining nutrient components of lake sediments.

19.
Zhonghua Yi Xue Za Zhi ; 90(34): 2392-5, 2010 Sep 14.
Artigo em Chinês | MEDLINE | ID: mdl-21092507

RESUMO

OBJECTIVE: To analyze the risk factors of novel severe influenza A (H1N1) with concurrent adult respiratory distress syndrome (ARDS). METHODS: A multivariable Logistic regression analysis was conducted for ARDS risk factors in controlled clinical trials for comparing the clinical features between the ARDS and non-ARDS groups and comparing ARDS patients' lymphocyte counts and T lymphocyte subsets between the smoking and non-smoking groups through a retrospective analysis of 92 novel influenza A (H1N1) patients who admitted to our hospital from October 2009 to January 2010. RESULTS: Through a single factor analysis between ARDS and non-ARDS groups, the comparisons in the factors including smoking (17 cases vs 11 cases), T lymphocyte subsets, lactate dehydrogenase (LDH), initial treatment point of oseltamivir and initial oxygen flow greater than 2 L/min (28 cases vs 18 cases) had statistically significant differences (all P<0.05). The comparison in T lymphocyte subsets had statistically significant difference between the smoking and non-smoking groups in ARDS patients (all P<0.05). The multivariable Logistic regression analysis showed that smoking (P=0.027, OR=8.05, 95%CI: 1.28-50.80) and initial oxygen flow greater than 2 L/min (P=0.010, OR=16.70, 95%CI: 3.29-84.84) were relevant to the incidence of ARDS in novel influenza A (H1N1) patients. CONCLUSION: Smoking and initial oxygen flow greater than 2 L/min were the risk factors of novel severe influenza A (H1N1) with concurrent ARDS.


Assuntos
Influenza Humana/complicações , Síndrome do Desconforto Respiratório/complicações , Fumar , Adolescente , Adulto , Idoso , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/epidemiologia , Modelos Logísticos , Pessoa de Meia-Idade , Análise Multivariada , Síndrome do Desconforto Respiratório/epidemiologia , Síndrome do Desconforto Respiratório/virologia , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
20.
Luminescence ; 25(5): 378-83, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19714670

RESUMO

In this paper, we described a simple approach for aqueous synthesis of highly luminescent ZnSe(S) alloyed quantum dots (QDs) in the presence of 3-mercaptopropionic acid as stabilizers using zinc chloride and NaHSe as precursors. The synthesis conditions were systematically investigated. We observed that the pH value of the Zn precursor solution had significant influence on the optical properties and the structure of the as-prepared ZnSe(S) QDs. The optimal pH value and molar ratio of Zn(2+) to HSe(-) were 12.0 and 25 : 1 respectively. Under the optimal conditions, we prepared highly photoluminescent ZnSe(S) QDs at up to 31% quantum yield (compared with Rhodamine 6G). The characterization of HRTEM and XRD showed that the ZnSe(S) QDs had good monodispersity and nice crystal structure. The fluorescence life time spectra demonstrated that ZnSe(S) QDs had a long lifetime in contrast to fluorescent dyes. Compared with the currently used organometallic approach, our method was 'green', the reaction condition was mild and the as-prepared ZnSe(S) QDs were water-soluble. More importantly, our method was low cost, and was very suitable for large-scale synthesis of highly luminescent ZnSe(S) QDs for the future applications.


Assuntos
Ácido 3-Mercaptopropiônico/química , Luminescência , Pontos Quânticos , Compostos de Selênio/química , Sulfetos/química , Compostos de Zinco/química , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Fotoquímica , Compostos de Selênio/síntese química , Soluções , Sulfetos/síntese química , Compostos de Zinco/síntese química
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