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1.
Ecol Lett ; 27(1): e14346, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38009408

RESUMO

Nitrogen (N) resorption is an important pathway of N conservation, contributing to an important proportion of plant N requirement. However, whether the ratio of N resorption to N requirement may be affected by environmental factors, mycorrhizal types or atmospheric CO2 concentration remains unclear. Here, we conducted a meta-analysis on the impacts of environmental factors and mycorrhizal types on this ratio. We found this ratio in ectomycorrhizal (EM) trees decreased with mean annual precipitation, mean annual temperature, soil total N content and atmospheric CO2 concentration and was significantly lower than that in arbuscular mycorrhizal (AM) trees. An in situ 15 N tracing experiment further confirmed that AM trees have a stronger reliance on N resorption than EM trees. Our study suggests that AM and EM trees potentially have different strategies for alleviation of progressive N limitation, highlighting the necessity of incorporating plant mycorrhizal types into Earth System Models.


Assuntos
Micorrizas , Árvores , Nitrogênio/metabolismo , Dióxido de Carbono/metabolismo , Plantas , Solo , Microbiologia do Solo , Florestas , Raízes de Plantas/metabolismo
2.
J Pharmacol Exp Ther ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38936977

RESUMO

Ovarian cancer is the most lethal gynecological malignancy, with a 5-year survival rate of approximately 50%. The dismal prognosis is due in part to metastatic disease and acquired drug resistance to conventional chemotherapies such as taxanes. Colchicine binding site inhibitors (CBSIs) are attractive alternatives to taxanes because they could potentially achieve oral bioavailability and overcome drug resistance associated with the prolonged use of taxanes. VERU-111 is one of the most advanced CBSIs that is orally available, potent, well-tolerated, and has shown good efficacy in several preclinical solid tumor models. Here, we demonstrate for the first time the in vitro potency of VERU-111 as well as its efficacy at inhibiting tumor growth and metastasis in an orthotopic ovarian cancer mouse model. VERU-111 has nanomolar potency against ovarian cancer cell lines and strongly inhibits colony formation, proliferation, invasion, and migration. VERU-111 disrupts microtubule formation to induce mitotic catastrophe and, ultimately, apoptosis in a concentration-dependent manner. The efficacy of VERU-111 was comparable with standard chemotherapy paclitaxel, the current first-line treatment for ovarian cancer, with no observed synergy with combination paclitaxel + VERU-111 treatment. In vivo, VERU-111 markedly suppressed ovarian tumor growth and completely suppressed distant organ metastasis. Together, these results support VERU-111 for its potential as a novel therapy for ovarian cancer, particularly for late-stage metastatic disease. Significance Statement VERU-111 is an investigational new drug and has comparable efficacy as paclitaxel in suppressing tumor cell proliferation, colony formation, and migration in ovarian cancer models in vitro and has potent in vivo anti-tumor and anti-metastatic activity in an orthotopic ovarian cancer mouse model. VERU-111 has low systemic toxicity and, unlike paclitaxel, is orally bioavailable and is not a substrate for the major drug efflux transporters, making it a promising and attractive alternative to taxane-based therapy.

3.
Hum Psychopharmacol ; 39(2): e2880, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37712506

RESUMO

INTRODUCTION: N-acetylcysteine (NAC) augmentation of antipsychotic medication has been studied in psychotic disorders but the results are inconsistent. This meta-analysis aimed to evaluate the efficacy and acceptability of NAC as an augmentation strategy for psychotic disorders. METHODS: PubMed, Web of Science, EMBASE, PsycINFO, Cochrane Library, and ClinicalTrials.gov were searched until the date of November 28, 2022. The inclusion criteria were randomized controlled trials (RCTs) comparing NAC and placebo in patients with psychotic disorders. The outcomes were the psychotic symptoms measured by the Positive and Negative Syndrome Scale (PANSS) and drop-out rates. RESULTS: A total of 594 patients from eight trials were included. The results showed that no difference was found in score changes of PANSS total, positive, negative, or general psychopathology scale scores between the NAC group and placebo group in both time points (≤24 weeks and >24 weeks). There was also no statistical difference in drop-out rates between the two groups. CONCLUSION: For the moment, it is not appropriate to recommend NAC as an augmentation of antipsychotic medication to treat psychotic disorders in routine clinical practice.


Assuntos
Antipsicóticos , Transtornos Psicóticos , Esquizofrenia , Humanos , Acetilcisteína/uso terapêutico , Antipsicóticos/uso terapêutico , Esquizofrenia/tratamento farmacológico , Transtornos Psicóticos/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto
4.
Glob Chang Biol ; 29(22): 6350-6366, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37602716

RESUMO

Long-term carbon and nitrogen dynamics in peatlands are affected by both vegetation production and decomposition processes. Here, we examined the carbon accumulation rate (CAR), nitrogen accumulation rate (NAR) and δ13 C, δ15 N of plant residuals in a peat core dated back to ~8500 cal year BP in a temperate peatland in Northeast China. Impacted by the tephra during 1160 and 789 cal year BP and climate change, the peatland changed from a fen dominated by vascular plants to a bog dominated by Sphagnum mosses. We used the Clymo model to quantify peat addition rate and decay constant for acrotelm and catotelm layers during both bog and fen phases. Our studied peatland was dominated by Sphagnum fuscum during the bog phase (789 to -59 cal year BP) and lower accumulation rates in the acrotelm layer was found during this phase, suggesting the dominant role of volcanic eruption in the CAR of the peat core. Both mean CAR and NAR were higher during the bog phase than during the fen phase in our study, consistent with the results of the only one similar study in the literature. Because the input rate of organic matter was considered to be lower during the bog phase, the decomposition process must have been much lower during the bog phase than during the fen phase and potentially controlled CAR and NAR. During the fen phase, CAR was also lower under higher temperature and summer insolation, conditions beneficial for decomposition. δ15 N of Sphagnum hinted that nitrogen fixation had a positive effect on nitrogen accumulation, particular in recent decades. Our study suggested that decomposition is more important for carbon and nitrogen sequestration than production in peatlands in most conditions and if future climate changes or human disturbance increase decomposition rate, carbon sequestration in peatlands will be jeopardized.


Assuntos
Carbono , Sphagnopsida , Humanos , Áreas Alagadas , Nitrogênio/análise , Plantas , Solo
5.
Glob Chang Biol ; 29(7): 1939-1950, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36585918

RESUMO

Whether nitrogen (N) availability will limit plant growth and removal of atmospheric CO2 by the terrestrial biosphere this century is controversial. Studies have suggested that N could progressively limit plant growth, as trees and soils accumulate N in slowly cycling biomass pools in response to increases in carbon sequestration. However, a question remains over whether longer-term (decadal to century) feedbacks between climate, CO2 and plant N uptake could emerge to reduce ecosystem-level N limitations. The symbioses between plants and microbes can help plants to acquire N from the soil or from the atmosphere via biological N2 fixation-the pathway through which N can be rapidly brought into ecosystems and thereby partially or completely alleviate N limitation on plant productivity. Here we present measurements of plant N isotope composition (δ15 N) in a peat core that dates to 15,000 cal. year BP to ascertain ecosystem-level N cycling responses to rising atmospheric CO2 concentrations. We find that pre-industrial increases in global atmospheric CO2 concentrations corresponded with a decrease in the δ15 N of both Sphagnum moss and Ericaceae when constrained for climatic factors. A modern experiment demonstrates that the δ15 N of Sphagnum decreases with increasing N2 -fixation rates. These findings suggest that plant-microbe symbioses that facilitate N acquisition are, over the long term, enhanced under rising atmospheric CO2 concentrations, highlighting an ecosystem-level feedback mechanism whereby N constraints on terrestrial carbon storage can be overcome.


Assuntos
Ecossistema , Nitrogênio , Nitrogênio/análise , Carbono/metabolismo , Dióxido de Carbono/fisiologia , Plantas/metabolismo , Solo
6.
Gastric Cancer ; 26(1): 69-81, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36114400

RESUMO

BACKGROUND: Ubiquitous mitochondrial creatine kinase (uMtCK) transfers high-energy phosphates from mitochondrially generated ATP to creatine to generate phosphocreatine. uMtCK overexpression has been reported in several malignant tumors, however, the clinical significance and impact of uMtCK in gastric cancer (GC) has not been comprehensively studied. METHODS: We first examined uMtCK expression in GC by quantitative real-time PCR and western blot assays. Then the clinicopathological significance of aberrant uMtCK expression was determined by immunohistochemical staining in a GC tissue microarray. Kaplan-Meier analysis was used for survival analysis. The biological functions of uMtCK in GC cells were explored by wound-healing, transwell assays and glucose metabolism assays in vitro as well as a liver metastasis model by spleen injection in nude mice in vivo. RESULTS: We verified that the expression of uMtCK was substantially elevated in GC tissues, significantly associating with a poorer prognosis in GC patients, especially for those with advanced stage. In univariate and multivariate analyses, uMtCK expression emerged as an independent prognostic factor for both disease-free survival and overall survival. Functionally, we demonstrated that uMtCK promoted glycolysis in GC cells and facilitated their migration, invasion and liver metastasis in vitro and in vivo. Mechanistically, uMtCK enhanced GC progression in a HK2-dependent glycolysis via acting the JNK-MAPK/JUN signaling pathway. CONCLUSIONS: uMtCK could serve as a novel independent prognostic biomarker as well as potential therapeutic target for GC patients, particularly for GC patients with an advanced UICC stage and tumor recurrence.


Assuntos
Neoplasias Hepáticas , Neoplasias Gástricas , Camundongos , Animais , Humanos , Neoplasias Gástricas/patologia , Creatina Quinase Mitocondrial/metabolismo , Camundongos Nus , Glicólise , Proliferação de Células , Prognóstico , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral
7.
Glob Chang Biol ; 28(22): 6728-6740, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35989426

RESUMO

Soil microbial biomass and microbial stoichiometric ratios are important for understanding carbon and nutrient cycling in terrestrial ecosystems. Here, we compiled data from 12245 observations of soil microbial biomass from 1626 published studies to map global patterns of microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), microbial biomass phosphorus (MBP), and their stoichiometry using a random forest model. Concentrations of MBC, MBN, and MBP were most closely linked to soil organic carbon, while climatic factors were most important for stoichiometry in microbial biomass ratios. Modeled seasonal MBC concentrations peaked in summer in tundra and in boreal forests, but in autumn in subtropical and in tropical biomes. The global mean MBC/MBN, MBC/MBP, and MBN/MBP ratios were estimated to be 10, 48, and 6.7, respectively, at 0-30 cm soil depth. The highest concentrations, stocks, and microbial C/N/P ratios were found at high latitudes in tundra and boreal forests, probably due to the higher soil organic matter content, greater fungal abundance, and lower nutrient availability in colder than in warmer biomes. At 30-100 cm soil depth, concentrations of MBC, MBN, and MBP were highest in temperate forests. The MBC/MBP ratio showed greater flexibility at the global scale than did the MBC/MBN ratio, possibly reflecting physiological adaptations and microbial community shifts with latitude. The results of this study are important for understanding C, N, and P cycling at the global scale, as well as for developing soil C-cycling models including soil microbial C, N, and P as important parameters.


Assuntos
Nitrogênio , Solo , Biomassa , Carbono/análise , China , Ecossistema , Nitrogênio/análise , Fósforo/análise , Microbiologia do Solo
8.
J Fluoresc ; 32(2): 669-680, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35040029

RESUMO

In this work, a convenient and dual-signal readout optical sensing platform for the sensitively and selectively determination of beta-glucosidase (ß-Glu) activity was reported using protein-inorganic hybrid nanoflowers [BSA-Cu3(PO4)2·3H2O] possessing peroxidase-mimicking activity. The nanoflowers (NFs) were facilely synthesized through a self-assembled synthesis strategy at room temperature. The as-prepared NFs could catalytically convert the colorless and non-fluorescent Amplex Red into colored and highly fluorescent resorufin in the presence of hydrogen peroxide via electron transfer process. ß-Glu could hydrolyze cyanogenic glycoside, using amygdalin (Amy) as a model, into cyanide ions (CN-), which can subsequently efficiently suppress the catalytic activity of NFs, accompanied with the fluorescence decrease and the color fading. The concentration of CN- was controlled by ß-Glu-triggered enzymatic reaction of Amy. Thus, a sensing system was established for fluorescent and visual determination of ß-Glu activity. Under the optimum conditions, the present fluorescent and visual bimodal sensing platform exhibited good sensitivity for ß-Glu activity assay with a detection limit of 0.33 U·L-1. The sensing platform was further applied to determinate ß-Glu in real samples and satisfactory results were attained. Additionally, the optical sensing system can potentially be a promising candidate for ß-Glu inhibitors screening.


Assuntos
Técnicas Biossensoriais/métodos , Nanoestruturas , Espectrometria de Fluorescência , beta-Glucosidase/análise , Peróxido de Hidrogênio , Oxazinas/química , Sensibilidade e Especificidade
9.
Int Urogynecol J ; 33(5): 1303-1309, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35347366

RESUMO

INTRODUCTION AND HYPOTHESIS: The coexistence of urinary incontinence (UI) and depression has been intensively examined in women. This study aimed to investigate the prevalence and some clinical correlates of depression in women with UI. METHODS: The National Health and Nutrition Examination Survey (NHANE) 2005-2018 was used in this cross-sectional study, and a total of 7250 UI patients were included. Patientss were defined as having UI if they answered "yes" to the UI screening question. Depression symptoms were measured by Personal Health Questionnaire (PHQ-9). RESULTS: The age-standardized prevalence of depression in women with UI was 13.7 (95% CI: 12.5-14.9). Multiple logistic regression showed that being younger (age <60 years), widowed, divorced or separated and having lower income, lower education level, more severe incontinence and mixed UI were associated with an increased likelihood of depression. CONCLUSIONS: This population-based study suggested that the prevalence of depression in women with UI was high. The main clinical correlates for depression were younger age (<60 years), lower education level, lower income, being widowed, divorced or separated, and having more severe incontinence and mixed UI.


Assuntos
Incontinência Urinária por Estresse , Incontinência Urinária , Estudos Transversais , Depressão/complicações , Depressão/epidemiologia , Feminino , Humanos , Pessoa de Meia-Idade , Inquéritos Nutricionais , Prevalência , Fatores de Risco , Inquéritos e Questionários , Incontinência Urinária/complicações , Incontinência Urinária/epidemiologia , Incontinência Urinária por Estresse/epidemiologia , Incontinência Urinária de Urgência/complicações
10.
Lipids Health Dis ; 21(1): 35, 2022 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-35369876

RESUMO

BACKGROUND: Although high serum cholesterol is widely recognized as a major risk factor for heart disease, the health effects of low cholesterol are less clear. Several studies have found a correlation between low cholesterol and depression, but the results are inconsistent. METHODS: Data from the National Health and Nutrition Examination Survey (NHANES) 2005-2018 were utilized in this cross-sectional study. The analysis of the relationship between cholesterol and depression was performed at three levels: low total cholesterol, low high-density lipoprotein (HDL) cholesterol and low-density lipoprotein (LDL) cholesterol. The inclusion criteria were as follows: (1) people with low (<4.14 mmol/L) or normal (4.14-5.16 mmol/L) total cholesterol for Sample 1; people with low (<1 mmol/L) or normal (≥1 mmol/L) HDL cholesterol levels for Sample 2; and people with low (<1.8 mmol/L) or normal (1.8-3.4 mmol/L) LDL cholesterol levels for Sample 3; and (2) people who completed the Patient Health Questionnaire-9 depression scale. Age, sex, educational level, race, marital status, self-rated health, alcohol status, smoking status, body mass index (BMI), poverty income ratio, physical function, comorbidities, and prescription use were considered potential confounders. The missing data were handled by multiple imputations of chained equations. Logistic regression was used to assess the relationship between low cholesterol and depression. RESULTS: After controlling for potential confounding factors in the multivariate logistic regression, no association was observed between depression and low total cholesterol (OR=1.0, 95% CI: 0.9-1.2), low LDL cholesterol (OR=1.0, 95% CI: 0.8-1.4), or low HDL cholesterol (OR=0.9, 95% CI: 0.8-1.1). The results stratified by sex also showed no association between low total cholesterol, low LDL cholesterol, low HDL cholesterol and depression in either men or women. CONCLUSION: This population-based study did not support the assumption that low cholesterol was related to a higher risk of depression. This information may contribute to the debate on how to manage people with low cholesterol in clinical practice.


Assuntos
Colesterol , Depressão , HDL-Colesterol , LDL-Colesterol , Estudos Transversais , Depressão/epidemiologia , Feminino , Humanos , Masculino , Inquéritos Nutricionais
11.
Glob Chang Biol ; 27(10): 2039-2048, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33559308

RESUMO

Optimal methods for incorporating soil microbial mechanisms of carbon (C) cycling into Earth system models (ESMs) are still under debate. Specifically, whether soil microbial physiology parameters and residual materials are important to soil organic C (SOC) content is still unclear. Here, we explored the effects of biotic and abiotic factors on SOC content based on a survey of soils from 16 locations along a ~4000 km forest transect in eastern China, spanning a wide range of climate, soil conditions, and microbial communities. We found that SOC was highly correlated with soil microbial biomass C (MBC) and amino sugar (AS) concentration, an index of microbial necromass. Microbial C use efficiency (CUE) was significantly related to the variations in SOC along this national-scale transect. Furthermore, the effect of climatic and edaphic factors on SOC was mainly via their regulation on microbial physiological properties (CUE and MBC). We also found that regression models on explanation of SOC variations with microbial physiological parameters and AS performed better than the models without them. Our results provide the empirical linkages among climate, microbial characteristics, and SOC content at large scale and confirm the necessity of incorporating microbial biomass and necromass pools in ESMs under global change scenarios.


Assuntos
Carbono , Solo , Carbono/análise , China , Florestas , Microbiologia do Solo
12.
AAPS PharmSciTech ; 22(2): 61, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33527250

RESUMO

Poorly water-soluble naringenin (NAR) was selected as a model drug and loaded into the porous MOFs for the construction of NAR@ZIF-8 inclusion complex. By film dispersion method, NAR@ZIF-8 was further encapsulated into liposomes to fabricate a novel drug delivery system. Liposomes and a novel drug delivery system were established. Subsequently, the lipid-drug ratio, phospholipid-cholesterol ratio, and hydration temperature were investigated using the Box-Behnken design based the single factor experiment. The prepared liposomes system showed spherical or quasi-spherical shape, uniform particle size distribution, and complete structure. More specifically, the average particle size was 113.2 ± 1.4 nm, and zeta potential was - 7.536 ± 0.264 mV. Moreover, the drug release behaviors of NAR, NAR@ZIF-8, and NAR@ZIF-8 liposomes were explored in vitro. Compared with free NAR and NAR@ZIF-8 which exhibited a burst drug release, NAR@ZIF-8 liposomes showed a more sustained release behavior with 79.86% drug release in 72 h. In vitro cytotoxicity experiments showed that, compared with free NAR and NAR@ZIF-8, NAR@ZIF-8 liposomes exhibited higher inhibition efficiency on lung adenocarcinoma A549 cells and gastric cancer SGC-7901 cells in a concentration-dependent manner.


Assuntos
Sistemas de Liberação de Medicamentos , Flavanonas/administração & dosagem , Estruturas Metalorgânicas/química , Linhagem Celular Tumoral , Liberação Controlada de Fármacos , Flavanonas/química , Flavanonas/farmacologia , Humanos , Lipossomos/administração & dosagem , Neoplasias/tratamento farmacológico , Neoplasias/patologia
13.
Glob Chang Biol ; 26(9): 5277-5289, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32506540

RESUMO

Microbial-derived nitrogen (N) is now recognized as an important source of soil organic N. However, the mechanisms that govern the production of microbial necromass N, its turnover, and stabilization in soil remain poorly understood. To assess the effects of elevated temperature on bacterial and fungal necromass N production, turnover, and stabilization, we incubated 15 N-labeled bacterial and fungal necromass under optimum moisture conditions at 10°C, 15°C, and 25°C. We developed a new 15 N tracing model to calculate the production and mineralization rates of necromass N. Our results showed that bacterial and fungal necromass N had similar mineralization rates, despite their contrasting chemistry. Most bacterial and fungal necromass 15 N was recovered in the mineral-associated organic matter fraction through microbial anabolism, suggesting that mineral association plays an important role in stabilizing necromass N in soil, independently of necromass chemistry. Elevated temperature significantly increased the accumulation of necromass N in soil, due to the relatively higher microbial turnover and production of necromass N with increasing temperature than the increases in microbial necromass N mineralization. In conclusion, we found elevated temperature may increase the contribution of microbial necromass N to mineral-stabilized soil organic N.


Assuntos
Nitrogênio , Solo , Carbono , Nitrogênio/análise , Microbiologia do Solo , Temperatura
15.
Mikrochim Acta ; 186(12): 806, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31745660

RESUMO

A fluorescent "turn off-on" nanoprobe is described for highly sensitive and selective determination of the activity of the enzyme ß-glucosidase (ß-Glu). Firstly, cysteine modified CuInS2 quantum dots (Cys-CuInS2 QDs) were prepared from indium(III) and copper(II) salts and the presence of thiourea. The red fluorescence of the Cys-CuInS2 QDs, with excitation/emission maxima at 590/656 nm, is quenched by Cu(II). However, in the presence of ß-Glu and the cyanogenic glycoside, enzymatic hydrolysis leads to the formation of cyanide. The latter competitively binds to Cu(II) owing to its high affinity for cyanide. This restores the fluorescence of the Cys-CuInS2 QDs. Under the optimum conditions, fluorescence increases linearly in the 0.5-700 U·L-1 ß-Glu activity range. The detection limit is 0.2 U·L-1. The nanoprobe was applied to analyze spiked soil samples, and satisfactory results were obtained. The average recoveries of ß-Glu were in the range of 96-103%, and the RSD was lower than 4.0%. The fluorescent probe can also be used to screen for ß-Glu inhibitors as demonstrated for castanospermine as an example. Graphical abstractSchematic representation of the fluorescent nanoprobe for ß-glucosidase activity detection and inhibitor screening by taking advantage of the fluorescence (FL) "turn-off" and "turn-on" feature of cysteine capped CuInS2 quantum dots (Cys-CuInS2 QDs).


Assuntos
Cobre/química , Corantes Fluorescentes/química , Índio/química , Pontos Quânticos/química , Sulfetos/química , beta-Glucosidase/análise , Amigdalina/química , Cianetos/química , Cisteína/química , Inibidores de Glicosídeo Hidrolases/química , Indolizinas/química , Limite de Detecção , Solo/química , Espectrometria de Fluorescência/métodos , beta-Glucosidase/antagonistas & inibidores
16.
Opt Express ; 26(10): 12632-12637, 2018 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-29801301

RESUMO

This paper proposes a novel method to substantially reduce motion-introduced phase error in phase-shifting profilometry. We first estimate the motion of an object from the difference between two subsequent 3D frames. After that, by leveraging the projector's pinhole model, we can determine the motion-induced phase shift error from the estimated motion. A generic phase-shifting algorithm considering phase shift error is then utilized to compute the phase. Experiments demonstrated that proposed algorithm effectively improved the measurement quality by compensating for the phase shift error introduced by rigid and nonrigid motion for a standard single-projector and single-camera digital fringe projection system.

17.
Anal Bioanal Chem ; 410(17): 4145-4152, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29663060

RESUMO

In this work, a novel simple fluorescent biosensor for the highly sensitive and selective detection of adrenaline was established. Firstly, water-soluble CuInS2 quantum dots (QDs) capped by L-Cys were synthesized via a hydrothermal synthesis method. Then, the positively charged adrenaline was assembled on the surface of CuInS2 QDs due to the electrostatic interactions and hydrogen bonding, which led to the formation of adrenaline-CuInS2 QD (Adr-CuInS2 QD) electrostatic complexes. Tyrosinase (TYR) can catalyze adrenaline to generate H2O2, and additionally oxidize the adrenaline to adrenaline quinone. Both the H2O2 and the adrenaline quinone can quench the fluorescence of the CuInS2 QDs through the electron transfer (ET) process. Thus, the determination of adrenaline could be facilely achieved by taking advantage of the fluorescence "turn off" feature of CuInS2 QDs. Under the optimum conditions, the fluorescence quenching ratio If/If0 (If and If0 were the fluorescence intensity of Adr-CuInS2 QDs in the presence and absence of TYR, respectively) was proportional to the logarithm of adrenaline concentration in the range of 1 × 10-8-1 × 10-4 mol L-1 with the detection limit of 3.6 nmol L-1. The feasibility of the proposed biosensor in real sample assay was also studied and satisfactory results were obtained. Significantly, the proposed fluorescent biosensor can also be utilized to screen TYR inhibitors. Graphical abstract Schematic illustration of the fluorescent biosensor for adrenaline detection (A) and tyrosinase inhibitor screening (B).


Assuntos
Técnicas Biossensoriais , Inibidores Enzimáticos/química , Epinefrina/análise , Monofenol Mono-Oxigenase , Técnicas Biossensoriais/tendências , Fluorescência , Concentração de Íons de Hidrogênio , Limite de Detecção , Monofenol Mono-Oxigenase/química
18.
Opt Express ; 24(20): 23289-23303, 2016 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-27828393

RESUMO

We propose a hybrid computational framework to reduce motion-induced measurement error by combining the Fourier transform profilometry (FTP) and phase-shifting profilometry (PSP). The proposed method is composed of three major steps: Step 1 is to extract continuous relative phase maps for each isolated object with single-shot FTP method and spatial phase unwrapping; Step 2 is to obtain an absolute phase map of the entire scene using PSP method, albeit motion-induced errors exist on the extracted absolute phase map; and Step 3 is to shift the continuous relative phase maps from Step 1 to generate final absolute phase maps for each isolated object by referring to the absolute phase map with error from Step 2. Experiments demonstrate the success of the proposed computational framework for measuring multiple isolated rapidly moving objects.

19.
Analyst ; 140(5): 1629-36, 2015 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-25632410

RESUMO

In this paper, we developed a near-infrared mercaptopropionic acid (MPA)-capped CuInS2 quantum dot (QD) fluorescence probe for the detection of acid phosphatases (ACP), which is an important biomarker and indicator of prostate cancer. The fluorescence of CuInS2 QDs could be quenched by Cu(2+), and then the addition of adenosine-5'-triphosphate (ATP) could effectively turn on the quenched fluorescence due to the strong interaction between Cu(2+) and ATP. The ACP could catalyze the hydrolysis of ATP, which would disassemble the complex of Cu(2+)-ATP. Therefore, the recovered fluorescence could be quenched again by the addition of ACP. In our method, the limit of detection (LOD) is considerably low for ACP detection in solution. Using the CuInS2 QDs fluorescence probe, we successfully performed in vitro imaging of human prostate cancer cells.


Assuntos
Fosfatase Ácida/análise , Corantes Fluorescentes , Neoplasias da Próstata/patologia , Pontos Quânticos , Espectrometria de Fluorescência/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Trifosfato de Adenosina/metabolismo , Cobre/química , Fluorescência , Corantes Fluorescentes/química , Humanos , Índio/química , Limite de Detecção , Masculino , Neoplasias da Próstata/enzimologia , Sulfetos/química , Células Tumorais Cultivadas
20.
Appl Nurs Res ; 28(2): 169-74, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25315140

RESUMO

PURPOSE: The present study aimed at examining the relationships among perceived stigma, social support, and quality of life (QOL) in people living with HIV (PLWH). METHODS: We recruited 190 participants meeting the inclusion criteria from two HIV clinics in Hunan, China. HIV-related Stigma Scale, the Chinese Version of the Medical Outcomes Study - Social Support Survey (MOS-SSS-C), and the Medical Outcomes Study-HIV (MOS-HIV) were used to measure the perceived stigma, social support and QOL in PLWH. RESULTS: The mean scores of the perceived stigma, social support, and QOL were 104.32, 53.63, and 61.97 respectively, which were in moderate range. Stepwise multivariate regression analysis showed (R(2)=.49, p<.01) a low score of internalized stigma and family stigma, a high score of tangible support for non-drug use and antiretroviral treatment, and high CD4 count predicted better QOL. CONCLUSION: Perceived stigma and social support are correlated with the QOL in PLWH. Interventions designed to decrease perceived stigma and strengthen social support from family are necessary to improve the QOL in PLWH.


Assuntos
Infecções por HIV/psicologia , Qualidade de Vida , Apoio Social , Estereotipagem , Adulto , Idoso , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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