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1.
PLoS One ; 15(3): e0230499, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32187230

RESUMO

Glycosphingolipids (GSLs) hexosylceramides and lactosylceramides are elevated in lupus mice and human patients with nephritis. Whereas other renal diseases characterized by increased GSL levels are thought to be a result of upregulated GSL synthesis, our results suggest elevated hexosylceramides and lactosylceramides in lupus nephritis is a result of increased catabolism of ganglioside GM3 due to significantly increased neuraminidase (NEU) activity. Thus, we hypothesized GM3 would be decreased in lupus nephritis kidneys and blocking NEU activity would reduce GSLs and improve disease in lupus mice. Female MRL/lpr lupus mice were treated with water or the NEU inhibitor oseltamivir phosphate at the onset of proteinuria to block GSL catabolism. Age-matched (non-nephritic) female MRL/MpJ lupus mice served as controls. Renal GM3 levels were significantly higher in the nephritic MRL/lpr water-treated mice compared to non-nephritic MRL/MpJ mice, despite significantly increased renal NEU activity. Blocking GSL catabolism increased, rather than decreased, renal and urine GSL levels and disease was not significantly impacted. A pilot study treating MRL/lpr females with GlcCer synthase inhibitor Genz-667161 to block GSL synthesis resulted in a strong significant negative correlation between Genz-667161 dose and renal GSL hexosylceramide and GM3 levels. Splenomegaly was negatively correlated and serum IgG levels were marginally correlated with increasing Genz-667161 dose. These results suggest accumulation of renal GM3 may be due to dysregulation of one or more of the GSL ganglioside pathways and inhibiting GSL synthesis, but not catabolism, may be a therapeutic approach for treating lupus nephritis.


Assuntos
Glicoesfingolipídeos/metabolismo , Nefrite Lúpica/tratamento farmacológico , Nefrite Lúpica/metabolismo , Animais , Ceramidas/metabolismo , Feminino , Gangliosídeo G(M3)/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Lactosilceramidas/metabolismo , Camundongos , Camundongos Endogâmicos MRL lpr , Neuraminidase/metabolismo , Oseltamivir/análogos & derivados , Oseltamivir/uso terapêutico , Ácidos Fosforosos/uso terapêutico , Projetos Piloto , Proteinúria/tratamento farmacológico , Proteinúria/metabolismo
2.
Molecules ; 25(1)2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31935900

RESUMO

Currently, significant attention is attracted to the problem of the development of the specific architecture and composition of the surface layer in order to control the biocompatibility of implants made of titanium and its alloys. The titanium surface properties can be tuned both by creating an inorganic sublayer with the desired morphology and by organic top coating contributing to bioactivity. In this work, we developed a composite biologically active coatings based on hybrid molecules obtained by chemical cross-linking of amino acid bisphosphonates with a linear tripeptide RGD, in combination with inorganic porous sublayer created on titanium by plasma electrolytic oxidation (PEO). After the addition of organic molecules, the PEO coated surface gets nobler, but corrosion currents increase. In vitro studies on proliferation and viability of fibroblasts, mesenchymal stem cells and osteoblast-like cells showed the significant dependence of the molecule bioactivity on the structure of bisphosphonate anchor and the linker. Several RGD-modified bisphosphonates of ß-alanine, γ-aminobutyric and ε-aminocaproic acids with BMPS or SMCC linkers can be recommended as promising candidates for further in vivo research.


Assuntos
Materiais Revestidos Biocompatíveis , Oligopeptídeos , Ácidos Fosforosos , Próteses e Implantes , Titânio , Linhagem Celular , Materiais Revestidos Biocompatíveis/química , Eletroquímica , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/metabolismo , Oligopeptídeos/química , Osteoblastos/metabolismo , Ácidos Fosforosos/química , Análise Espectral , Propriedades de Superfície , Titânio/química
3.
J Chromatogr A ; 1613: 460697, 2020 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-31733896

RESUMO

S9570-Fe(III), a modified chelating resin containing sulphonated monophosphonic acid bifunctional groups, was used for the fluoride removal from aqueous phase for the first time. The results specified that S9570-Fe(III) exhibited better adsorption towards the fluoride ions as compared to the other commonly used chelating resins having monofunctional group such as iminodiacetic acid, sulfonic acid or carboxylic acid. Adsorption thermodynamic and kinetic studies of S9570-Fe(III) chelating resin for the fluoride also have been carried out. The thermodynamic results demonstrated that the adsorption was a spontaneous process accompanied with a gradual decrease in entropy and the low temperature was favorable for the fluoride ion adsorption. The kinetic experiments showed that the resin exhibited a rapid initial adsorption behavior and the adsorption process more complied with the pseudo-second order reaction model which indicating that the whole adsorption process was controlled by a combined mechanism of intraparticle diffusion and chemical sorption. Adsorption mechanism of S9570-Fe(III) resin for fluoride ions was predicted. The study demonstrated the effectiveness of the phosphoric-sulfonic acid bifunctional group chelating resin to remove fluoride, and provided a novel type removal method for the fluoride.


Assuntos
Técnicas de Química Analítica/métodos , Fluoretos/isolamento & purificação , Ácidos Fosforosos/química , Resinas Sintéticas/química , Ácidos Sulfônicos/química , Adsorção , Quelantes/química , Compostos Férricos/química , Cinética , Termodinâmica , Água/química , Poluentes Químicos da Água/isolamento & purificação
4.
J Chromatogr A ; 1612: 460659, 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-31708214

RESUMO

In this work, multilayer zirconia-coated silica (ZrO2/SiO2-n) microspheres were successfully produced by a straightforward hydrothermal procedure with a low concentration of Zr4+ (5 mM) under low potential of hydrogen (pH) conditions (pH = =2). The obtained ZrO2/SiO2-n materials exhibited favorable characteristics for high-performance liquid chromatography (HPLC) separation, including high surface area and pore volume, good pore structure, narrow particle size, and pore size distribution. In addition, the zirconia coverage in the mesopores was confirmed by soaking the material in 1 M NaOH solution, with the particles showing strong resistance to the basic solution. The obtained ZrO2/SiO2-n stationary phases were packed into a fused-silica capillary tubing for the separation of alkaloids in hydrophilic interaction chromatography (HILIC) mode, and a column efficiency of 47,800 plates/m was obtained for berberine on a ZrO2/SiO2-6 micro column. The ZrO2/SiO2-6 microspheres were further modified by dodecylphosphonic acid (C12P-2-ZrO2/SiO2-6); the C12P-2-ZrO2/SiO2-6 material showed great potential for application in reversed-phase liquid chromatography (RPLC) mode. The C12P-2-ZrO2/SiO2-6 micro column showed a column efficiency of 55,000 plates/m for naphthalene and 51,300 plates/m for benzene.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Hidrogênio/química , Microesferas , Ácidos Fosforosos/química , Dióxido de Silício/química , Zircônio/química , Alcaloides/análise , Alcaloides/isolamento & purificação , Cromatografia de Fase Reversa , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Porosidade , Reprodutibilidade dos Testes
5.
Talanta ; 206: 120198, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514838

RESUMO

Due to highly fluorinated and di-anionic characters, it is great challenging to enrich perfluoroalkyl phosphonic acids (PFPAs). According to the unique chemical properties and molecular structure of PFPAs, a monolithic adsorbent using dodecafluoroheptyl acrylate and 4-vinylbenzyltrimethylammonium chloride as mixed functional monomers was synthesized and utilized as the extraction medium of multiple monolithic fibers solid-phase microextraction (MMF-SPME). Results well evidenced that the obtained adsorbent could enrich PFPAs effectively by means of multiple interactions including fluorophilic and anion-exchange interactions. Under the optimized synthesized and extraction conditions, a sensitive approach for the monitoring of trace levels of PFPAs in water and vegetable samples was developed by the combination of MMF-SPME and high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). Limits of detection (LODs, S/N = 3) for water and vegetable samples were in the ranges of 0.00011-0.00086 µg/L and 0.0022-0.055 µg/kg, respectively. The introduced method was successfully applied to monitor target PFPAs in lake water, wastewater, pumpkin and cucumber samples. Recoveries at different spiking levels and the relative standard deviations for precision were in the ranges of 80.6-120% and 0.9-12%, respectively. Compared to previously reported approaches, the current method displays some merits such as simple operation, satisfactory sensitivity, low cost and eco-friendliness.


Assuntos
Fluorcarbonetos/análise , Contaminação de Alimentos/análise , Ácidos Fosforosos/análise , Polímeros/química , Poluentes Químicos da Água/análise , Adsorção , Cromatografia Líquida de Alta Pressão , Cucumis sativus/química , Cucurbita/química , Lagos/análise , Limite de Detecção , Compostos de Amônio Quaternário/química , Microextração em Fase Sólida/métodos , Espectrometria de Massas em Tandem , Verduras/química , Águas Residuárias/análise
6.
Chem Biodivers ; 16(11): e1900375, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31512351

RESUMO

New aziridine 2-phosphonic acids were prepared by monohydrolysis of the aziridine 2-phosphonates that were obtained by the modified Gabriel-Cromwell reaction of vinyl phosphonate or α-tosylvinyl phosphonate with a primary amine or a chiral amine. The cellular cytotoxicity of these compounds was tested against the HCT-116 colorectal cancer cell lines and the CCD-18Co normal colon fibroblast lines using the MTT assay. Three of the synthesized phosphonic acid derivatives 2e (ethyl hydrogen {(2S)-1-[(1S)-1-(naphthalen-2-yl)ethyl]aziridin-2-yl}phosphonate), 2h (ethyl hydrogen (1-benzylaziridin-2-yl)phosphonate), and 2i (ethyl hydrogen (1-cyclohexylaziridin-2-yl)phosphonate) showed higher cytotoxicity than the reference cancer treatment agent etoposide. Cell death was through a robust induction of apoptosis even more effectively than etoposide, a well-known apoptosis inducing agent.


Assuntos
Antineoplásicos/farmacologia , Aziridinas/farmacologia , Ácidos Fosforosos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Aziridinas/síntese química , Aziridinas/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Ácidos Fosforosos/síntese química , Ácidos Fosforosos/química
7.
N Engl J Med ; 381(9): 803-815, 2019 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-31339677

RESUMO

BACKGROUND: Two drugs under consideration for inclusion in antiretroviral therapy (ART) regimens for human immunodeficiency virus (HIV) infection are dolutegravir (DTG) and tenofovir alafenamide fumarate (TAF). There are limited data on their use in low- and middle-income countries. METHODS: We conducted a 96-week, phase 3, investigator-led, open-label, randomized trial in South Africa, in which we compared a triple-therapy combination of emtricitabine (FTC) and DTG plus either of two tenofovir prodrugs - TAF (TAF-based group) or tenofovir disoproxil fumarate (TDF) (TDF-based group) - against the local standard-of-care regimen of TDF-FTC-efavirenz (standard-care group). Inclusion criteria included an age of 12 years or older, no receipt of ART in the previous 6 months, a creatinine clearance of more than 60 ml per minute (>80 ml per minute in patients younger than 19 years of age), and an HIV type 1 (HIV-1) RNA level of 500 copies or more per milliliter. The primary end point was the percentage of patients with a 48-week HIV-1 RNA level of less than 50 copies per milliliter (as determined with the Snapshot algorithm from the Food and Drug Administration; noninferiority margin, -10 percentage points). We report the primary (48-week) efficacy and safety data. RESULTS: A total of 1053 patients underwent randomization from February 2017 through May 2018. More than 99% of the patients were black, and 59% were female. The mean age was 32 years, and the mean CD4 count was 337 cells per cubic millimeter. At week 48, the percentage of patients with an HIV-1 RNA level of less than 50 copies per milliliter was 84% in the TAF-based group, 85% in the TDF-based group, and 79% in the standard-care group, findings that indicate that the DTG-containing regimens were noninferior to the standard-care regimen. The number of patients who discontinued the trial regimen was higher in the standard-care group than in the other two groups. In the per-protocol population, the standard-care regimen had equivalent potency to the other two regimens. The TAF-based regimen had less effect on bone density and renal function than the other regimens. Weight increase (both lean and fat mass) was greatest in the TAF-based group and among female patients (mean increase, 6.4 kg in the TAF-based group, 3.2 kg in the TDF-based group, and 1.7 kg in the standard-care group). No resistance to integrase inhibitors was identified in patients receiving the DTG-containing regimens. CONCLUSIONS: Treatment with DTG combined with either of two tenofovir prodrugs (TAF and TDF) showed noninferior efficacy to treatment with the standard-care regimen. There was significantly more weight gain with the DTG-containing regimens, especially in combination with TAF, than with the standard-care regimen. (ADVANCE ClinicalTrials.gov number, NCT03122262.).


Assuntos
Adenina/análogos & derivados , Antirretrovirais/administração & dosagem , Infecções por HIV/tratamento farmacológico , HIV-1 , Compostos Heterocíclicos com 3 Anéis/administração & dosagem , Ácidos Fosforosos/administração & dosagem , Adenina/administração & dosagem , Adenina/efeitos adversos , Adolescente , Adulto , Antirretrovirais/efeitos adversos , Densidade Óssea/efeitos dos fármacos , Contagem de Linfócito CD4 , Quimioterapia Combinada , Feminino , Inibidores de Integrase de HIV/administração & dosagem , HIV-1/genética , HIV-1/isolamento & purificação , Compostos Heterocíclicos com 3 Anéis/efeitos adversos , Humanos , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Ácidos Fosforosos/efeitos adversos , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Pró-Fármacos/administração & dosagem , RNA Viral/sangue , Uracila/administração & dosagem , Uracila/análogos & derivados , Carga Viral , Adulto Jovem
8.
Chem Biodivers ; 16(7): e1900167, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31145516

RESUMO

A dozen of phosphonic and phosphinic acid derivatives containing pyridine moiety were synthesized and its inhibitory activity toward mushroom tyrosinase was investigated. Moreover, molecular docking of these compounds to the active site of the enzyme was performed. All the compounds (1-10) demonstrated the inhibitory effect with the IC50 and inhibition constants ranging millimolar concentrations. The obtained results indicate that the compounds show different types of inhibition (competitive, noncompetitive, mixed), but all of them are reversible inhibitors. The obtained outcomes allowed to make the structure-activity relationship (SAR) analysis. Compound 4 ([(benzylamino)(pyridin-2-yl)methyl]phenylphosphinic acid) revealed the lowest IC50 value of 0.3 mm and inhibitory constant of Ki 0.076 mm, with noncompetitive type and reversible mechanism of inhibition. According to SAR analysis, introducing bulky phenyl moieties to phosphonic and amino groups plays an important role in the inhibitory potency on activity of mushroom tyrosinase and could be useful in design and development of a new class of potent organophosphorus inhibitors of tyrosinase. Combined results of molecular docking and SAR analysis can be helpful in designing novel tyrosinase inhibitors of desired properties. They may have broad application in food industry and cosmetology.


Assuntos
Inibidores Enzimáticos/farmacologia , Simulação de Acoplamento Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores , Ácidos Fosfínicos/farmacologia , Ácidos Fosforosos/farmacologia , Agaricus/enzimologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Cinética , Estrutura Molecular , Monofenol Mono-Oxigenase/metabolismo , Ácidos Fosfínicos/química , Ácidos Fosfínicos/isolamento & purificação , Ácidos Fosforosos/química , Ácidos Fosforosos/isolamento & purificação , Relação Estrutura-Atividade
10.
Colloids Surf B Biointerfaces ; 179: 488-494, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31005744

RESUMO

Vesicles possess unique biofilm structures and offer biomimetic advantages for drug and gene delivery. Herein, we report the spontaneous vesicle formation from ultrashort alkyl-phosphonic acids in the presence of amino acids. The aggregation characteristics and self-assembly structures of vesicles in aqueous solution were investigated by using dynamic light scattering, zeta potential, and cryo-transmission electron microscopy. We combined low-field nuclear magnetic resonance and Fourier transform infrared spectroscopy to study the H-proton-induced multilamellar vesicle formation. When we increased the molar fraction of serine, stable and closed spherical vesicles were formed at relatively low critical micelle concentrations. This transition of the self-assembled structure indicates that vesicle formation occurs when the chain length and the magnitude of the surface charge cause a fluctuation in the volume of the vesicle. Density functional theory reveals the critical role of the mixed alkyl-phosphonic acid/amino acid-enhanced electrostatic attraction between the head groups and hydrogen bonds associated with the aggregated states.


Assuntos
Ácidos Fosforosos/química , Serina/química , Água/química , Difusão Dinâmica da Luz , Espectroscopia de Ressonância Magnética , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática
11.
Korean J Intern Med ; 34(4): 802-810, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30959583

RESUMO

BACKGROUND/AIMS: The optimal management of chronic hepatitis B (CHB) patients with partial virologic response (PVR) to tenofovir disoproxil fumarate (TDF) remains unclear. We aimed to evaluate the long-term efficacy of prolonged TDF therapy in treatment-naïve CHB patients with PVR to TDF therapy in real practice. METHODS: We retrospectively investigated the efficacy of prolonged TDF therapy in treatment-naïve CHB patients with PVR to TDF. PVR was defined as a decrease in serum hepatitis B virus (HBV) DNA over 2 log10 IU/mL from baseline, with detectable HBV DNA by real-time polymerase chain reaction at week 48. RESULTS: We included 232 patients who underwent TDF therapy for over 48 weeks. Forty-two patients (18.1%) showed PVR. In multivariate analysis, hepatitis B e antigen (HBeAg) positivity, and high levels of serum HBV DNA at baseline and week 12 were independent predictive factors for PVR during TDF therapy. Out of 42 patients with PVR, 39 (92.9%) achieved virologic response (VR) during continuous TDF treatment; the cumulative VR rates at 24, 36, and 48 months were 79.8%, 88.2%, and 95.6%, respectively. With an additional 12 months of therapy, VR was achieved in 28/31 (90.3%) patients with HBV DNA < 100 IU/mL, compared to 5/11 (45.5%) patients with HBV DNA ≥ 100 IU/mL, at week 48. CONCLUSION: The vast majority of patients achieved VR through prolonged TDF therapy, thus TDF treatment can be maintained in nucleos(t)ide-naïve patients with PVR at week 48, especially in those with low viremia.


Assuntos
Adenina/análogos & derivados , Antivirais/administração & dosagem , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Ácidos Fosforosos/administração & dosagem , Adenina/administração & dosagem , Adenina/efeitos adversos , Adulto , Antivirais/efeitos adversos , Esquema de Medicação , Feminino , Vírus da Hepatite B/genética , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Ácidos Fosforosos/efeitos adversos , Estudos Retrospectivos , Resposta Viral Sustentada , Fatores de Tempo , Resultado do Tratamento , Carga Viral
12.
Analyst ; 144(11): 3483-3487, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-30892295

RESUMO

A redox-sensitive inter-conversion between ascorbic acid (ASC) and its oxidized form dehydroascorbic acid (DHA) in the intracellular environment has been of exceptional interest to recent metabolomics and pharmaceutical research. We developed a chromatographic protocol to instantly determine these vitamers with each identity from cellular extracts, without any labeling and pretreatments. Owing to its simplicity, one can readily continue the assay for hours, an otherwise difficult to cover timescale at which the intracellular DHA-ASC conversion comes into play. The method was validated for the analysis of pancreatic cancer cells, to our knowledge the first-ever study on a nucleated cell type, to trace in detail their kinetics of glucose transporter-dependent DHA uptake and, simultaneously, that for the intracellular ASC conversion. The simplest of all the relevant techniques and yet with the unique ability to provide each vitamer identity on a high-throughput basis, this method should offer the most practical option for VC-involved physiological and pharmaceutical studies including high-dose VC cancer therapy.


Assuntos
Ácido Ascórbico/análise , Ácido Ascórbico/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Ácido Desidroascórbico/análise , Ácido Desidroascórbico/metabolismo , Ácido Ascórbico/química , Linhagem Celular Tumoral , Ácido Desidroascórbico/química , Eritrócitos/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Humanos , Oxirredução , Pâncreas/citologia , Pâncreas/metabolismo , Ácidos Fosforosos/química
13.
J Acquir Immune Defic Syndr ; 80(5): 551-558, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30865051

RESUMO

BACKGROUND: HPTN 067 assessed the feasibility of daily and non-daily dosing of open-label emtricitabine/tenofovir disoproxil fumarate (FTC/TDF)-based pre-exposure prophylaxis (PrEP). METHODS: Factors associated with sex-related PrEP adherence were assessed among men who have sex with men (MSM) randomized to one of 3 PrEP dosing arms in HPTN 067 in New York City. Sex-related PrEP adherence was defined per protocol as at least 1 PrEP tablet taken within 4 days pre-sex and at least 1 additional PrEP tablet taken within 24 hours post-sex, assessed via electronic drug monitoring and weekly interviews. Demographic data and behavioral measures were evaluated for association with sex-related PrEP adherence. Logistic regression for clustered data was used to estimate the unadjusted and adjusted odds ratios. RESULTS: Of 176 randomized MSM participants, 59% were Black, 10% White, 25% Hispanic, and 6% other; median age was 31 years. In the multivariable analyses, higher sex-related PrEP adherence was significantly associated with daily dosing arm, older age, employment, and higher PrEP adherence behavioral skills. Lower sex-related PrEP adherence was significantly associated with identifying as Black or Hispanic (compared with White), opiate use, and reporting "I forgot" as an adherence barrier. CONCLUSIONS: This analysis identified populations of MSM who might benefit from additional support to optimize PrEP adherence, including those who are younger, unemployed, or opiate users. MSM with lower PrEP behavioral skills may benefit from targeted interventions. Further study is needed to assess racial and ethnic disparities in PrEP adherence, which may reflect broader social and economic inequalities not captured in this study.


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV/uso terapêutico , Emtricitabina/uso terapêutico , Infecções por HIV/prevenção & controle , Homossexualidade Masculina/psicologia , Adesão à Medicação/psicologia , Ácidos Fosforosos/uso terapêutico , Profilaxia Pré-Exposição/estatística & dados numéricos , Adenina/administração & dosagem , Adenina/uso terapêutico , Adulto , Quimioterapia Combinada , Emtricitabina/administração & dosagem , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Masculino , Adesão à Medicação/estatística & dados numéricos , Cidade de Nova Iorque , Ácidos Fosforosos/administração & dosagem
14.
J Colloid Interface Sci ; 545: 195-199, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30878785

RESUMO

Herein, we present a simple strategy to enhance the stability of water-sensitive SrLiAl3N4:Eu2+ phosphor through embedding the phosphor particles into low-melting Sn-P-F-O glass using phosphor-in-glass (PiG) approach. After being immersed in water for 96 h, the emission intensity of the SrLiAl3N4:Eu2+-PiG sample was maintained at 80% of its pristine intensity, indicating the moisture-resistance property of SrLiAl3N4:Eu2+ was significantly enhanced. Employing the narrow-band red-emitting SrLiAl3N4:Eu2+-PiG sample and a blue COB (chip-on-board), a plant growing LED device was fabricated. The emission spectrum of the device matches well with the absorption of Chlorophyl (a and b) in plants, indicating the as-prepared SrLiAl3N4:Eu2+-PiG are suitable to be applied in plant lighting field. We believe that this simple method reported in this communication can be easily expanded to other water-sensitive luminescence materials.


Assuntos
Vidro/química , Substâncias Luminescentes/química , Metais/química , Ácidos Fosforosos/química , Vapor/análise , Cor , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Medições Luminescentes/instrumentação , Tamanho da Partícula , Plantas/metabolismo , Propriedades de Superfície , Temperatura , Fatores de Tempo
15.
Nanotoxicology ; 13(4): 510-526, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30704361

RESUMO

Innovative nanotechnology aims to develop particles that are small, monodisperse, smart, and do not cause unintentional side effects. Uniform magnetic Fe3O4 nanoparticles (12 nm in size) were prepared by thermal decomposition of iron(III) oleate. To make them colloidally stable and dispersible in water and cell culture medium, they were modified with phosphonic acid- (PA) and hydroxamic acid (HA)-terminated poly(ethylene glycol) yielding PA-PEG@Fe3O4 and HA-PEG@Fe3O4 nanoparticles; conventional γ-Fe2O3 particles were prepared as a control. Advanced techniques were used to evaluate the properties and safety of the particles. Completeness of the nanoparticle coating was tested by real-time polymerase chain reaction. Interaction of the particles with primary human peripheral blood cells, cellular uptake, cytotoxicity, and immunotoxicity were also investigated. Amount of internalized iron in peripheral blood mononuclear cells was 72, 38, and 25 pg Fe/cell for HA-PEG@Fe3O4, γ-Fe2O3, and PA-PEG@Fe3O4, respectively. Nanoparticles were localized within the cytoplasm and in the extracellular space. No cytotoxic effect of both PEGylated nanoparticles was observed (0.12-75 µg/cm2) after 24 and 72-h incubation. Moreover, no suppressive effect was found on the proliferative activity of T-lymphocytes and T-dependent B-cell response, phagocytic activity of monocytes and granulocytes, and respiratory burst of phagocytes. Similarly, no cytotoxic effect of γ-Fe2O3 particles was observed. However, they suppressed the proliferative activity of T-lymphocytes (75 µg/cm2, 72 h) and also decreased the phagocytic activity of monocytes (15 µg/cm2, 24 h; 3-75 µg/cm2, 72 h). We thus show that newly developed particles have great potential especially in cancer diagnostics and therapy.


Assuntos
Proliferação de Células/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Nanopartículas de Magnetita/toxicidade , Nanomedicina/métodos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/imunologia , Células Cultivadas , Citocinas/metabolismo , Humanos , Ácidos Hidroxâmicos/química , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/patologia , Nanopartículas de Magnetita/química , Tamanho da Partícula , Fagocitose/efeitos dos fármacos , Fagocitose/imunologia , Ácidos Fosforosos/química , Polietilenoglicóis/química , Explosão Respiratória/efeitos dos fármacos , Explosão Respiratória/imunologia , Propriedades de Superfície
16.
Biomed Chromatogr ; 33(6): e4488, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30656732

RESUMO

In this study, poly(vinylphosphonic acid-co-ethylene dimethacrylate), poly(VPA-co-EDMA) capillary monolith was synthesized as a starting material for obtaining a stationary phase for microscale enrichment of phosphopeptides. The chelation of active phosphonate groups with Ti (IV) ions gave a macroporous monolithic column with a mean pore size of 5.4 µm. The phosphopeptides from different sources were enriched on Ti (IV)-attached poly(VPA-co-EDMA) monolith using a syringe-pump. The monolithic capillary columns exhibited highly sensitive/selective enrichment performance with phosphoprotein concentrations as low as 1.0 fmol/mL. Six different phosphopeptides were detected with high intensity by the treatment of ß-casein digest with the concentration of 1.0 fmol/mL, using Ti (IV)@poly(VPA-co-EDMA) monolith. Highly selective enrichment of phosphopeptides was also successfully carried out even at trace amounts, in a complex mixture of digested proteins (molar ratio of ß-casein to bovine serum albumin, 1:1500) and three phosphopeptides were successfully detected. Four highly intense signals of phosphopeptides in human serum were also observed with high signal-to-noise ratio and a clear background after enrichment with Ti (IV)@poly(VPA-co-EDMA) monolith. It was concluded that the capillary microextraction system enabled fast, efficient and robust enrichment of phosphopeptides from microscale complex samples. The whole enrichment process was completed within 20 min, which was shorter than in the previously reported studies.


Assuntos
Cromatografia de Afinidade/métodos , Fosfopeptídeos/sangue , Ácidos Fosforosos/química , Titânio/química , Cromatografia de Afinidade/instrumentação , Humanos , Ácidos Polimetacrílicos , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
17.
J Environ Manage ; 234: 237-244, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30634116

RESUMO

Activated carbon is one of the most studied materials for the adsorption of textile dyes. The adsorptive properties of this material are a result of its high specific surface area and some of the functional groups acquired during the chemical activation. This work reports the preparation of a composite material using CarZN400 activated carbon and polyelectrolyte poly(VPA-co-TEGDMA). The adsorptive properties of the material obtained are a result of the combination of the high specific surface area of the carbon and the ionic exchange capability of the polyelectrolyte. The covering of the surface of activated carbon with poly(VPA-co-TEGDMA) allowed to obtain a composite material (CarZN400C) with greater adsorption capacity for cationic dyes compared to the carbon. The adsorption isotherms of the dyes fit Langmuir's model, and the adsorptive capacities for cationic dyes for CarZN400C ranged between 222 and 416 mg/g. The kinetic study showed that the adsorption of basic and acid dyes fit the pseudo-second order kinetic model. CarZN400C also exhibited the ability to adsorb textile dyes present in wastewater. It was observed that, when making a previous treatment of the wastewater using coagulation-flocculation followed by adsorption using CarZN400C, it was possible to obtain removal percentages of color close to 100%. The wastewaters treated by coagulation-flocculation and adsorption improved their quality by decreasing the value for COD.


Assuntos
Carvão Vegetal , Poluentes Químicos da Água , Adsorção , Corantes , Ácidos Fosforosos , Polivinil , Indústria Têxtil , Têxteis , Eliminação de Resíduos Líquidos
19.
Org Lett ; 21(1): 147-151, 2019 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-30565949

RESUMO

Two practical entries to arylomycin antibiotics core structures are investigated. In route A, the activation of l-Hpg for the key macrolactamization step is achieved in 89% yield in the presence of unprotected phenol and amine functionalities. Alternatively, a propanephosphonic acid anhydride (T3P)-promoted coupling between thel-Tyr and l-Ala moieties in route B led to a facile macrolactamization in 68% yield with a marked reduction in competing oligomerization.


Assuntos
Antibacterianos/síntese química , Oligopeptídeos/síntese química , Aminas/química , Antibacterianos/química , Estrutura Molecular , Oligopeptídeos/química , Fenóis/química , Ácidos Fosforosos/química
20.
Gut Liver ; 13(1): 93-103, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30400723

RESUMO

Background/Aims: To investigate the treatment efficacy and renal safety of long-term tenofovir disoproxil fumarate (TDF) therapy in chronic hepatitis B (CHB) patients with preserved renal function. Methods: The medical records of 919 CHB patients who were treated with TDF therapy were reviewed. All patients had preserved renal function with an estimated glomerular filtration rate (eGFR) of at least 60 mL/min/1.73 m². Results: A total of 426 patients (184 treatment-naïve and 242 treatment-experienced) were included for analysis. A virologic response (VR) was defined as achieving an undetectable serum hepatitis B virus (HBV) DNA level, and the overall VR was 74.9%, 86.7%, and 89.4% at the 1, 2, and 3-year follow-ups, respectively. Achieving a VR was not influenced by previous treatment experience, TDF combination therapy, or antiviral resistance. In a multivariate analysis, being hepatitis B e antigen positive at baseline and having a serum HBV DNA level ≥2,000 IU/mL at 12 months were associated with lower VR rates during the long-term TDF therapy. The overall renal impairment was 2.9%, 1.8%, and 1.7% at the 1, 2, and 3-year follow-ups, respectively. With regard to renal safety, underlying diabetes mellitus (DM) and an initial eGFR of 60 to 89 mL/min/1.73 m² were significant independent predictors of renal impairment. Conclusions: TDF therapy appears to be an effective treatment option for CHB patients with a preserved GFR. However, patients with underlying DM and initial mild renal dysfunction (eGFR, 60 to 89 mL/min/1.73 m²) have an increased risk of renal impairment.


Assuntos
Adenina/análogos & derivados , Antivirais/administração & dosagem , Taxa de Filtração Glomerular/efeitos dos fármacos , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Ácidos Fosforosos/administração & dosagem , Adenina/administração & dosagem , Adenina/efeitos adversos , Adulto , Antivirais/efeitos adversos , Esquema de Medicação , Feminino , Hepatite B Crônica/fisiopatologia , Hepatite B Crônica/virologia , Humanos , Rim/efeitos dos fármacos , Rim/fisiopatologia , Rim/virologia , Nefropatias/induzido quimicamente , Nefropatias/epidemiologia , Nefropatias/virologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Ácidos Fosforosos/efeitos adversos , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
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