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1.
Luminescence ; 36(3): 691-697, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33226717

RESUMO

A novel diarylethene-based ratiometric fluorescent sensor with full symmetric structure, 1o, was designed and synthesized successfully. 1o could identify lysine (Lys) with high selectivity and sensitivity and the fluorescence emission peak was red shifted 85 nm upon addition of Lys, which could realize ratio recognition. It exhibited excellent anti-interference performance in the presence of various amino acids in CH3 CN/H2 O (7/3, v/v) solution. Moreover, the limit of detection of 1o to Lys could reach 0.019 µM based on a good linear range of 0-40 µM. In addition, the fluorescence emission intensity of 1o could be turned off/on by ultraviolet/visible light due to the special structure of diarylethene. A logic circuit was designed with three inputs. The ratiometric fluorescent sensor 1o could be as a new tool and provide a new method for detection of Lys.


Assuntos
Corantes Fluorescentes , Lisina , Luz , Lógica , Espectrometria de Fluorescência
2.
Luminescence ; 34(8): 911-917, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31353776

RESUMO

A new ratiometric probe composed of a dansyl-rhodamine dyad for the detection of Hg2+ via fluorescence resonance energy transfer was designed and synthesized. Rhodamine, dansyl chloride, and hydrazide were selected as the acceptor, donor, and reaction site, respectively. It displayed high selectivity and sensitivity to Hg2+ with obvious colour change and fluorescence change due to Hg2+ -assisted hydrolysis of rhodamine hydrazide. A good linear relationship ranging from 0 to 16 µM and 0-28 µM for the Hg2+ concentration was found based on absorbance and fluorescence assay, respectively. Detection limits of absorbance and fluorescence for Hg2+ were calculated to be 1.22 µM and 9.10 µM, respectively.


Assuntos
Colorimetria , Compostos de Dansil/química , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/química , Mercúrio/análise , Imagem Óptica , Rodaminas/química , Corantes Fluorescentes/síntese química , Células HeLa , Humanos , Estrutura Molecular
3.
Anal Bioanal Chem ; 409(25): 5943-5954, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28801832

RESUMO

Reliable measurement of total testosterone and estradiol is critical for their use as biomarkers of hormone-related disorders in patient care and translational research. We developed and validated a mass spectrometry method to simultaneously quantify these analytes in human serum without chemical derivatization. Serum is equilibrated with isotopic internal standards and treated with acidic buffer to release hormones from their binding proteins. Lipids are isolated and polar impurities are removed by two serial liquid-liquid extraction steps. Total testosterone and estradiol are measured using liquid chromatography tandem mass spectrometry (LC-MS/MS) in combination of positive and negative electrospray ionization modes. The method shows broad analytical measurement range for both testosterone 0.03-48.5 nM (0.75-1400 ng/dL) and estradiol 11.0-5138 pM (2.99-1400 pg/mL) and excellent agreement with certified reference materials (mean bias less than 2.1% to SRM 971, BCR 576, 577, and 578) and a high order reference method (mean bias 1.25% for testosterone and -0.84% for estradiol). The high accuracy of the method was monitored and certified by CDC Hormone Standardization (HoSt) Program for 2 years with mean bias -0.7% (95% CI -1.6% to 0.2%) for testosterone and 0.1% (95% CI -2.2% to 2.3%) for estradiol. The method precision over a 2-year period for quality control pools at low, medium, and high concentrations was 2.7-2.9% for testosterone and 3.3-5.3% for estradiol. With the consistently excellent accuracy and precision, this method is readily applicable for high-throughput clinical and epidemiological studies.


Assuntos
Cromatografia Líquida/métodos , Estradiol/sangue , Espectrometria de Massas em Tandem/métodos , Testosterona/sangue , Adolescente , Adulto , Criança , Feminino , Humanos , Técnicas de Diluição do Indicador , Isótopos/sangue , Limite de Detecção , Extração Líquido-Líquido/métodos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Anal Bioanal Chem ; 409(4): 931-937, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27796450

RESUMO

Human exposure to polycyclic aromatic hydrocarbons (PAHs) can be assessed through monitoring of urinary mono-hydroxylated PAHs (OH-PAHs). Gas chromatography (GC) has been widely used to separate OH-PAHs before quantification by mass spectrometry in biomonitoring studies. However, because GC requires derivatization, it can be time consuming. We developed an on-line solid phase extraction coupled to isotope dilution-high performance liquid chromatography-tandem mass spectrometry (on-line-SPE-HPLC-MS/MS) method for the quantification in urine of 1-OH-naphthalene, 2-OH-naphthalene, 2-OH-fluorene, 3-OH-fluorene, 1-OH-phenanthrene, the sum of 2-OH and 3-OH-phenanthrene, 4-OH-phenanthrene, and 1-OH-pyrene. The method, which employed a 96-well plate platform and on-line SPE, showed good sensitivity (i.e., limits of detection ranged from 0.007 to 0.09 ng/mL) and used only 100 µL of urine. Accuracy, calculated from the recovery percentage at three spiking levels, varied from 94 to 113 %, depending on the analyte. The inter- and intra-day precision, calculated from 20 repeated measurements of two quality control materials, varied from 5.2 to 16.7 %. Adequate method performance was also confirmed by acceptable recovery (83-102 %) of two NIST standard reference materials (3672 and 3673). This high-throughput on-line-SPE-HPLC-MS/MS method can be applied in large-scale epidemiological studies. Graphical abstract Example LC-MS chromatogram of urinary mono-hydroxylated PAH metabolites.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Hidrocarbonetos Policíclicos Aromáticos/urina , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Hidroxilação , Limite de Detecção , Controle de Qualidade , Padrões de Referência , Reprodutibilidade dos Testes
5.
Clin Chem ; 61(12): 1495-504, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26510959

RESUMO

BACKGROUND: Limited information is available about testosterone concentrations representative of the general US population, especially children, women, and non-Hispanic Asians. METHODS: We obtained nationally representative data for total testosterone (totalT), measured with standardized LC-MS/MS, for the US population age 6 years and older from the 2011-2012 National Health and Nutrition Examination Survey (NHANES). We analyzed 6746 serum samples and calculated the geometric means, distribution percentiles, and covariate-adjusted geometric means by age, sex, and race/ethnicity. RESULTS: The 10th-90th percentiles of totalT values in adults (≥20 years) was 150-698 ng/dL (5.20-24.2 nmol/L) in men, 7.1-49.8 ng/dL (0.25-1.73 nmol/L) in women, and 1.0-9.5 ng/dL (0.04-0.33 nmol/L) in children (6-10 years old). Differences among race/ethnic groups existed in children and men: covariate-adjusted totalT values in non-Hispanic Asians were highest among children (58% compared to non-Hispanic black children) and lowest among men (12% compared to Mexican-American men). Covariate-adjusted totalT values in men were higher at age 55-60 years compared to ages 35 and 80 years, a pattern different from that observed in previous NHANES cycles. CONCLUSIONS: TotalT patterns were different among age groups in men compared with previous NHANES cycles. Covariate-adjusted totalT values peaked at age 55-60 years in men, which appeared to be consistent with the increased use of exogenous testosterone. Differences among race/ethnic groups existed and appeared more pronounced in children than adults.


Assuntos
Inquéritos Nutricionais/estatística & dados numéricos , Testosterona/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , População Negra , Criança , Cromatografia Líquida , Feminino , Humanos , Masculino , Americanos Mexicanos , Pessoa de Meia-Idade , Espectrometria de Massas em Tandem , Estados Unidos , População Branca
6.
Anal Bioanal Chem ; 407(14): 4079-90, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25796529

RESUMO

A headspace solid-phase microextraction gas chromatography-mass spectrometry (SPME GC-MS) method is described, to screen seafood for volatile organic compounds (VOCs) associated with petrochemical taint. VOCs are extracted from the headspace of heated sample homogenates by adsorption onto a SPME fiber and desorbed for analysis by GC-MS. Targeted compounds are determined semi-quantitatively using representative calibration standards for the various classes (alkanes, alkylbenzenes, indanes/tetralins, and naphthalenes) of VOCs analyzed. Sample preparation is minimal, and the analyses are rapid and automated with a capacity of 50 samples per day. The method was optimized in terms of headspace temperature, sample heating time, extraction time, and desorption time using oyster samples fortified with target compounds. Calibrations for hydrocarbon components were linear in the range of 8.3-167 ng/g; the limit of detection ranged between 0.05 and 0.21 ng/g, and the limit of quantitation between 0.16 and 0.69 ng/g. Good precision (RSD < 10 % at 16.7 ng/g for individual VOCs) and accuracy (recovery range 89-118 % at 25 ng/g) were obtained in oyster, crab, shrimp, and finfish matrices. The trueness of the method was demonstrated by quantifying VOCs at 1-2-ppb levels in oyster fortified with certified reference material NIST SRM 1491a. Following single laboratory validation, the method was employed for the determination of VOCs in seafood exposed to oil contaminated seawater and for the determination of background VOC levels in seafood species from the Gulf of Mexico and local food stores. The method as described can be used to supplement human sensory testing for petrochemical taint in seafood.


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Petróleo/análise , Alimentos Marinhos/análise , Microextração em Fase Sólida/métodos , Animais , Braquiúros/química , Peixes , Golfo do México , Ostreidae/química , Penaeidae/química , Reprodutibilidade dos Testes , Água do Mar/química , Poluentes Químicos da Água/química
7.
ACS Nano ; 18(24): 15978-15990, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38847448

RESUMO

Sulfur-substituted dicyanomethylene-4H-chromene (DCM) derivatives based on the intramolecular charge transfer (ICT) mechanism were designed as near-infrared (NIR) fluorescent dyes. Using the Knoevenagel condensation method, the S-DCM-OH(835) fluorescence dye was synthesized, which had an emission wavelength exceeding 800 nm and 220 nm of a Stokes shift. Compared to commercial ICG, S-DCM-OH(835) was not only synchronized in emission wavelength but also far superior in Stokes shifts. These advantages made the design of S-DCM-NIR(835) based on this dye potentially valuable for biological applications. Based on this chemical structure, a fluorescent S-DCM-NIR(835) nanoprobe with a mean diameter of 17.69 nm was fabricated as the NIR imaging nanoprobe. Results showed that the nanoprobe maintained the high-specificity identification of cysteine (Cys) via the Michael addition reaction, with the detection limitation of 0.11 µM endogenous Cys. More importantly, in an ischemic stroke mouse model, the S-DCM-NIR(835) nanoprobe could monitor the Cys concentration change at stroke lesion due to the disruption of Cys metabolism under the ischemic stroke condition. Such a S-DCM-NIR(835) nanoprobe could not only differentiate the severity of the ischemic stroke using response time but also quantify the concentration of Cys in real-time in vivo.


Assuntos
Cisteína , Corantes Fluorescentes , Raios Infravermelhos , AVC Isquêmico , Corantes Fluorescentes/química , Animais , Cisteína/química , Camundongos , AVC Isquêmico/diagnóstico por imagem , Imagem Óptica , Nanopartículas/química , Humanos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Masculino , Benzopiranos/química
8.
Cancer Epidemiol Biomarkers Prev ; 33(1): 80-87, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-37823832

RESUMO

BACKGROUND: Biomarkers of exposure are tools for understanding the impact of tobacco use on health outcomes if confounders like demographics, use behavior, biological half-life, and other sources of exposure are accounted for in the analysis. METHODS: We performed multiple regression analysis of longitudinal measures of urinary biomarkers of alkaloids, tobacco-specific nitrosamines, polycyclic aromatic hydrocarbons, volatile organic compounds (VOC), and metals to examine the sample-to-sample consistency in Waves 1 and 2 of the Population Assessment of Tobacco and Health (PATH) Study including demographic characteristics and use behavior variables of persons who smoked exclusively. Regression coefficients, within- and between-person variance, and intra-class correlation coefficients (ICC) were compared with biomarker smoking/nonsmoking population mean ratios and biological half-lives. RESULTS: Most biomarkers were similarly associated with sex, age, race/ethnicity, and product use behavior. The biomarkers with larger smoking/nonsmoking population mean ratios had greater regression coefficients related to recency of exposure. For VOC and alkaloid metabolites, longer biological half-life was associated with lower within-person variance. For each chemical class studied, there were biomarkers that demonstrated good ICCs. CONCLUSIONS: For most of the biomarkers of exposure reported in the PATH Study, for people who smoke cigarettes exclusively, associations are similar between urinary biomarkers of exposure and demographic and use behavior covariates. Biomarkers of exposure within-subject consistency is likely associated with nontobacco sources of exposure and biological half-life. IMPACT: Biomarkers measured in the PATH Study provide consistent sample-to-sample measures from which to investigate the association of adverse health outcomes with the characteristics of cigarettes and their use.


Assuntos
Alcaloides , Produtos do Tabaco , Compostos Orgânicos Voláteis , Humanos , Meia-Vida , Biomarcadores , Fumar/epidemiologia
9.
J Natl Cancer Inst ; 116(3): 379-388, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-37856326

RESUMO

BACKGROUND: Studying carcinogens in tobacco and nontobacco sources may be key to understanding the pathogenesis and geographic distribution of esophageal cancer. METHODS: The Golestan Cohort Study has been conducted since 2004 in a region with high rates of esophageal squamous cell carcinoma. For this nested study, the cases comprised of all incident cases by January 1, 2018; controls were matched to the case by age, sex, residence, time in cohort, and tobacco use. We measured urinary concentrations of 33 exposure biomarkers of nicotine, polycyclic aromatic hydrocarbons, volatile organic compounds, and tobacco-specific nitrosamines. We used conditional logistic regression to calculate odds ratios (ORs) and 95% confidence intervals for associations between the 90th vs the 10th percentiles of the biomarker concentrations and incident esophageal squamous cell carcinoma. RESULTS: Among individuals who did not currently use tobacco (148 cases and 163 controls), 2 acrolein metabolites, 2 acrylonitrile metabolites, 1 propylene oxide metabolite, and one 1,3-butadiene metabolite were significantly associated with incident esophageal squamous cell carcinoma (adjusted odds ratios between 1.8 and 4.3). Among tobacco users (57 cases and 63 controls), metabolites of 2 other volatile organic compounds (styrene and xylene) were associated with esophageal squamous cell carcinoma (OR = 6.2 and 9.0, respectively). In tobacco users, 2 tobacco-specific nitrosamines (NNN and N'-Nitrosoanatabine) were also associated with esophageal squamous cell carcinoma. Suggestive associations were seen with some polycyclic aromatic hydrocarbons (especially 2-hydroxynaphthalene) in nonusers of tobacco products and other tobacco-specific nitrosamines in tobacco users. CONCLUSION: These novel associations based on individual-level data and samples collected many years before cancer diagnosis, from a population without occupational exposure, have important public health implications.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Nitrosaminas , Hidrocarbonetos Policíclicos Aromáticos , Compostos Orgânicos Voláteis , Humanos , Biomarcadores , Estudos de Coortes , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/etiologia , Carcinoma de Células Escamosas do Esôfago/epidemiologia , Carcinoma de Células Escamosas do Esôfago/etiologia , Incidência , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Compostos Orgânicos Voláteis/efeitos adversos
10.
Int J Gen Med ; 16: 499-505, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36785558

RESUMO

Purpose: This study aimed to investigate the effect of emergency percutaneous coronary intervention (PCI) combined with sacubitril-valsartan (Entresto) on the cardiac prognosis in patients with acute myocardial infarction (AMI). Patients and Methods: A total of 78 AMI patients who were treated in our hospital between January 2020 and September 2021 were included and randomly divided into treatment group and control group (n=39 per group). In the control group, patients were treated with primary PCI combined with irbesartan; in the treatment group, patients were treated with primary PCI combined with Entresto; pharmacotherapy lasted for 3 months. The left ventricular remodeling indexes, serum N-terminal B-type natriuretic peptide precursor (NT-proBNP), serum homocysteine (HCY), cystatin C (CysC) and results of 6-minute walk test (6MWT) before and after treatment were compared between two groups. The incidence of major adverse cardiovascular events (MACE) was determined and compared between them. Results: (1) Before treatment, there were no marked differences in the left ventricular end-systolic diameter (LVESD), left ventricular end-diastolic diameter (LVEDD), interventricular septum thickness (IVST), NT-proBNP, left ventricular ejection fraction (LVEF), HCY, CysC, and results of 6MWT between two groups (P>0.05). After treatment, the LVEDS, LVEDD, NT-proBNP, HCY and CysC in the control group were significantly higher than in the treatment group (P<0.05). The recovery of LVEF and 6MWT in the treatment group was significantly better than in the control group (P<0.05). After treatment, there was no significant difference in the IVST between two groups (P>0.05). (2) The incidence of MACE in the control group was significantly higher than in the treatment group (P<0.05). Conclusion: Compared with irbesartan, Entresto can further improve the cardiac function, prevent ventricular remodeling, and further optimize the clinical efficacy of PCI in AMI patients.

11.
Nano Converg ; 10(1): 3, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609947

RESUMO

Photothermal therapy (PTT) combined with second near-infrared (NIR-II) fluorescence imaging (FI) has received increasing attention owing to its capacity for precise diagnosis and real-time monitoring of the therapeutic effects. It is of great clinical value to study organic small molecular fluorophores with both PTT and NIR-II FI functions. In this work, we report a skillfully fluorescent lipid nanosystem, the RR9 (RGDRRRRRRRRRC) peptide-coated anionic liposome loaded with organic NIR-II fluorophore IR-1061 and chemotherapeutic drug carboplatin, which is named RRIALP-C4. According to the structural interaction between IR-1061 and phospholipid bilayer demonstrated by molecular dynamics simulations, IR-1061 is rationally designed to possess the H-aggregated state versus the free state, thus rendering RRIALP-C4 with the activated dual-channel integrated function of intravital NIR-II FI and NIR-I PTT. Functionalization of RRIALP-C4 with RR9 peptide endows the specifically targeting capacity for αvß3-overexpressed tumor cells and, more importantly, allows IR-1061 to transfer the H-aggregated state from liposomes to the tumor cell membrane through enhanced membrane fusion, thereby maintaining its PTT effect in tumor tissues. In vivo experiments demonstrate that RRIALP-C4 can effectively visualize tumor tissues and systemic blood vessels with a high sign-to-background ratio (SBR) to realize the synergistic treatment of thermochemotherapy by PTT synergistically with temperature-sensitive drug release. Therefore, the strategy of enhanced PTT through H-aggregation of NIR-II fluorophore in the tumor cell membrane has great potential for developing lipid nanosystems with integrated diagnosis and treatment function.

12.
Artigo em Inglês | MEDLINE | ID: mdl-37372644

RESUMO

Firefighters are at an increased risk of cancer due to their occupational exposure to combustion byproducts, especially when those compounds penetrate the firefighter personal protective equipment (PPE) ensemble. This has led to questions about the impact of base layers (i.e., shorts vs. pants) under PPE ensembles. This study asked 23 firefighters to perform firefighting activities while wearing one of three different PPE ensembles with varying degrees of protection. Additionally, half of the firefighters unzipped their jackets after the scenario while the other half kept their jackets zipped for five additional minutes. Several volatile organic compound (VOC) and naphthalene air concentrations outside and inside of hoods, turnout jackets, and turnout pants were evaluated; biological (urinary and exhaled breath) samples were also collected. VOCs and naphthalene penetrated the three sampling areas (hoods, jackets, pants). Significant (p-value < 0.05) increases from pre- to post-fire for some metabolites of VOCs (e.g., benzene, toluene) and naphthalene were found. Firefighters wearing shorts and short sleeves absorbed higher amounts of certain compounds (p-value < 0.05), and the PPE designed with enhanced interface control features appeared to provide more protection from some compounds. These results suggest that firefighters can dermally absorb VOCs and naphthalene that penetrate the PPE ensemble.


Assuntos
Poluentes Ocupacionais do Ar , Bombeiros , Exposição Ocupacional , Hidrocarbonetos Policíclicos Aromáticos , Humanos , Poluentes Ocupacionais do Ar/análise , Naftalenos , Exposição Ocupacional/análise , Equipamento de Proteção Individual , Hidrocarbonetos Policíclicos Aromáticos/análise
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 267(Pt 1): 120528, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34742156

RESUMO

Hydrogen peroxide (H2O2), a member of small-molecule reactive oxygen species (ROS), plays vital roles in normal physiological activities and the occurrence of many diseases. In this work, two off-on fluorescent probes, QX8A-H2O2 and QX9A-H2O2, were firstly designed for H2O2 detection with novel fused quinoxalines as the fluorophores and boronate moiety as the reaction sites. By comparing the optical properties, QX9A-H2O2 with better performance was selected for further studies. QX9A-H2O2 exhibited a high sensitivity to H2O2 with the detection limit as low as 46 nM, and displayed a good selectivity towards H2O2 over other reactants such as ROS, biothiols and various ions. The detection was based on the intramolecular charge transfer (ICT), proceeding through a sequential oxidative hydrolysis, 1,6-rearrangement elimination and decarboxylation process to release the fluorophore QX9A. Moreover, probe QX9A-H2O2 was cell permeable and was successfully employed in both exogenous and endogenous H2O2 imaging in living cells.


Assuntos
Corantes Fluorescentes , Peróxido de Hidrogênio , Células HeLa , Humanos , Limite de Detecção , Oxirredução , Espécies Reativas de Oxigênio
14.
Biomater Sci ; 10(11): 2772-2788, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35502881

RESUMO

NIR-II FI has emerged as a promising imaging tool for in vivo precise diagnosis and visualization towards various diseases, ascribed to its merits of attenuated light scattering and tissue absorption and ignorable auto-fluorescence. Owing to its superiority in high specificity, low toxicity, and ignorable invasiveness, photothermal therapy (PTT) has developed as one of the most potential treatment methods for cancer treatment. Although organic optical agents with a donor-acceptor-donor (D-A-D) skeleton have been extensively applied to NIR-II FI and PTT, most were based on the three weak electron acceptors benzobisthiadiazole (BBTD), diketopyrrolopyrrole (DPP), and thiadiazoloquinoxaline (TTQ). Although the acceptor TTQ has developed as a promising acceptor to synthesize molecules for high-resolution NIR-II FI and PTT, reviews focused on TTQ based NIR-II organic molecules for NIR-II FI and PTT were still rarely reported. Hence, this review systemically summarized the current advanced process of TTQ based D-A-D type organic molecules for NIR-II FI and PTT. Firstly, some examples for NIR-II FI of tissue and immune and thrombosis NIR-II FI were presented in detail. Some examples of NIR-II FI-navigated PTT or combination therapy were discussed. Finally, some pending challenges in applying them to NIR-II FI and PTT are discussed.


Assuntos
Nanopartículas , Terapia Fototérmica , Imagem Óptica , Polímeros
15.
Environ Pollut ; 305: 119216, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35395351

RESUMO

High-density culturing with excessive feeding of commercial feed has caused heavy metals pollution to agricultural production system. In this study, the dynamic changes and transfer of heavy metals in rice-crayfish coculture system (RCCS) and crayfish intensive culture system (CICS) within a completed culture cycle were systematically quantified. Our results showed that Cd in feed represented more than 50% of the total Cd input, and the inputs of As and Cr were mainly from irrigation. The residues of As and Pb in RCCS were slightly higher than those in CICS, while the residues of Cd and Cr in RCCS were far fewer than those in CICS. Moreover, the metal pollution index in CICS was 0.781, while it was 0.543 in the RCCS. Furthermore, a large proportion of the Cd and Pb in CICS was released into the external environment through drainage. Notably, the absorption and solidification of heavy metals by straw did not increase the residues of As and Pb in the major components of RCCS in the second year. Compared to CICS, RCCS did not produce many heavy metal residues or cause heavy metal discharge pressure on the external environment, and its food product had a low risk of heavy metal contamination.


Assuntos
Metais Pesados , Oryza , Poluentes do Solo , Animais , Astacoidea , Cádmio , China , Técnicas de Cocultura , Monitoramento Ambiental , Chumbo , Metais Pesados/análise , Oryza/química , Medição de Risco , Solo/química , Poluentes do Solo/análise
16.
Adv Healthc Mater ; 11(21): e2201158, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35943849

RESUMO

NIR-II fluorescence imaging (NIR-II FI) and photothermal therapy (PTT) have received broad attentions in precise tumor diagnosis and effective treatment attributed to high-resolution and deep tissue imaging, negligible invasivity, and high-efficiency treatment. Although many fluorescent molecules have been designed and conducted for NIR-II FI and PTT, it is still an enormous challenge for researchers to pioneer some rational design guidelines to improve fluorescence brightness. Organic D-A-type molecules, including small molecules and conjugated polymers, can be designed and developed to improve fluorescence brightness due to their tunable and easy functionalized chemical structures, allowing molecules tailored photophysical properties. In this review, some approaches to the development and design strategies of D-A type small molecules and conjugated polymers for the enhancement of fluorescence brightness are systemically introduced. Meanwhile, some applications of PTT and PTT-based combination therapy (such as PDT, chemotherapy, or gas therapy) assisted by NIR-II FI-based single or multiimaging technologies are classified and represented in detail as well. Finally, the current issues and challenges of NIR-II organic molecules in NIR-II FI-navigated PTT are summarized and discussed, which gives some guidelines for the future development direction of NIR-II organic molecules for NIR-II FI-navigated PTT.


Assuntos
Nanopartículas , Terapia Fototérmica , Fototerapia , Linhagem Celular Tumoral , Imagem Óptica , Polímeros/química , Nanopartículas/química
17.
Int J Hyg Environ Health ; 242: 113971, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35472749

RESUMO

BACKGROUND: Refined coal tar sealant (RCTS) emulsions are used to seal the surface of asphalt pavement. Nine of the 22 polycyclic aromatic hydrocarbons (PAHs) evaluated in this study are classified as known, probable, or possible human carcinogens. Exposure assessment research for RCTS workers has not been published previously. OBJECTIVES: The overall objective of this study was to develop a representative occupational exposure assessment of PAH exposure for RCTS workers based on worksite surveys. The specific aims were to: 1) quantify full-shift airborne occupational exposures to PAHs among RCTS workers; 2) quantify workers' dermal exposures to PAHs; 3) quantify biomarkers of PAH exposure in workers' urine; 4) identify specific job titles associated with RCTS exposure; and 5) apply these results to a biological exposure index to assess risk of potential genotoxicity from occupational exposures. METHODS: A total of twenty-one RCTS workers were recruited from three companies. Personal and area air samples were collected using a modification of NIOSH Method 5515. Dermal exposure was assessed by hand and neck wipes before and after shifts. Twenty-two PAHs were quantified via gas chromatography-mass spectrometry selected ion monitoring. Internal dose was estimated by quantifying select PAH metabolites in pre- and post-shift urine samples using on-line solid phase extraction-high performance liquid chromatography-tandem mass spectrometry. RESULTS: PAH levels in the worker breathing zones were highest for naphthalene, acenaphthene, and phenanthrene, with geometric means of 52.1, 11.4, and 9.8 µg/m3, respectively. Hand wipe levels of phenanthrene, fluoranthene and pyrene were the highest among the 22 PAHs with geometric means of 7.9, 7.7, and 5.5 µg/cm2, respectively. Urinary PAH biomarkers for naphthalene, fluorene, phenanthrene, and pyrene were detected in all workers and were higher for post-shift samples than those collected pre-shift. Urinary concentrations of the metabolite 1-hydroxypyrene were greater than the American Conference of Governmental Industrial Hygienists (ACGIH) Biological Exposure Index (BEI) for this metabolite in 89 percent of post-shift samples collected on the final day of the work week or field survey. Statistically significances were found between concentrations of fluorene, naphthalene, and phenanthrene in the breathing zone of workers and their corresponding urinary PAH biomarkers. Workers were placed in two work place exposure groups: applicators and non-applicators. Applicators had higher total PAH concentrations in personal breathing zone (PBZ) air samples than non-applicators and were more likely to have post-shift hand wipe concentrations significantly higher than pre-shift concentrations. Concentrations of post-shift urinary biomarkers were higher, albeit not significantly, for applicators than non-applicators. CONCLUSIONS: The exposure results from RCTS worker samples cannot be explained by proximal factors such as nearby restaurants or construction. Air and skin concentration levels were substantially higher for RCTS workers than previously published levels among asphalt workers for all PAHs. PAH profiles on skin wipes were more consistent with RCTS sealant product than air samples. Last day post-shift urinary concentrations of 1-hydroxypyrene greatly exceeded the ACGIH BEI benchmark of 2.5 µg/L in 25 of 26 samples, which suggests occupational exposure and risk of genotoxicity. When pyrene and benzo[a]pyrene were both detected, concentration ratios from personal exposure samples were used to calculate the adjusted BEI. Concentrations of 1-hydroxypyrene exceeded the adjusted BEIs for air, hand wipes, and neck wipes in most cases. These results indicate the need to increase safety controls and exposure mitigation for RCTS workers.


Assuntos
Poluentes Ocupacionais do Ar , Alcatrão , Exposição Ocupacional , Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Ocupacionais do Ar/análise , Biomarcadores/urina , Alcatrão/análise , Monitoramento Ambiental/métodos , Fluorenos/análise , Humanos , Hidrocarbonetos/análise , Hidrocarbonetos/química , Naftalenos/análise , Exposição Ocupacional/análise , Fenantrenos/urina , Hidrocarbonetos Policíclicos Aromáticos/urina , Pirenos
18.
Artigo em Inglês | MEDLINE | ID: mdl-35162490

RESUMO

Limited data are available for how biomarkers of tobacco exposure (BOE) change when cigarette smokers transition to using electronic nicotine delivery systems (ENDS). Using biomarker data from Waves 1 (2013-2014) and 2 (2014-2015) of the PATH Study, we examined how mean BOE concentrations, including metabolites of nicotine, tobacco-specific nitrosamines (TSNA), polycyclic aromatic hydrocarbons (PAH), and volatile organic compounds (VOC) and metals, changed when 2475 adult smokers transitioned to using ENDS or quit tobacco products. Exclusive smokers who transitioned to dual use had a significant decrease in NNAL (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol), but not nicotine metabolites, most PAHs, metals, or VOCs. Exclusive smokers who became dual users had significant reductions in total nicotine equivalents, NNAL, and 2CyEMA (acrylonitrile metabolite), but only in those who reduced cigarettes per day (CPD) by >=50%. Smokers who transitioned to exclusive ENDS use had significant reductions in most TSNAs, PAHs, and VOCs; however, nicotine metabolites did not decrease in dual users who became exclusive ENDS users. Smokers who quit tobacco use had significant decreases in nicotine metabolites, all TSNAs, most PAHs, and most VOCs. Cigarette smokers who became dual users did not experience significant reductions in most BOEs. Reductions were impacted by changes in CPD. However, transitioning from smoking to no tobacco or exclusive ENDS use was associated with reduced exposure to most BOEs measured. Future analyses could incorporate additional waves of PATH data and examine changes in biomarker exposure by ENDS device type and CPD.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Adulto , Biomarcadores/análise , Humanos , Fumantes , Nicotiana , Uso de Tabaco
19.
Mol Biol Rep ; 38(2): 819-25, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20383745

RESUMO

Visfatin, a newly identified proinflammatory adipokine, has been linked to coronary artery disease (CAD). The -1535C>T polymorphism (rs61330082) located in the visfatin gene promoter is reportedly associated with proinflammatory status. However, it is unclear whether this polymorphism correlates with plasma levels of inflammatory markers including visfatin, hs-CRP, IL-6 and TNF-α in CAD patients. The present study was to investigate the potential association of the -1535C>T polymorphism with plasma levels of visfatin, IL-6, C reactive protein (hs-CRP) and TNF-α in patients with CAD. We conducted a hospital based study with 171 CAD patients to examine the association between the -1535C>T polymorphism and plasma levels of visfatin, hs-CRP, IL-6 and TNF-α. Plasma visfatin levels were markedly different between patients with stable angina pectoris (SAP, 11.91 ± 0.70 ng/l) and those with unstable angina pectoris (UAP, 17.49 ± 0.20 ng/l) or acute myocardial infarction (AMI, 16.63 ± 0.22 ng/l; SAP versus UAP or AMI, P < 0.05). Compared with the CC genotype, variant genotypes CT and TT correlated with significantly lower levels of visfatin, hs-CRP, IL-6 and TNF-α in the SAP group (P < 0.05), with lower levels of hs-CRP and IL-6 in the UAP group (P < 0.05), and with lower levels of visfatin in the AMI group (P < 0.05) after adjustment for age, gender, smoking, hypertension, diabetes, dyslipidemia and medication. Our results suggest that the -1535C>T polymorphism is associated with decreased plasma levels of inflammatory markers in CAD patients, reflecting that this polymorphism might provide a useful marker for predicting the development of CAD events.


Assuntos
Doença da Artéria Coronariana/genética , Inflamação/genética , Nicotinamida Fosforribosiltransferase/sangue , Nicotinamida Fosforribosiltransferase/genética , Regiões Promotoras Genéticas , Adipocinas/metabolismo , Idoso , Proteína C-Reativa/genética , Feminino , Genótipo , Humanos , Interleucina-6/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Fatores Sexuais , Fator de Necrose Tumoral alfa/genética
20.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 33(5): 495-8, 2011 Oct.
Artigo em Zh | MEDLINE | ID: mdl-22338131

RESUMO

OBJECTIVE: To evaluate the role of intracoronary electrocardiogram (IcECG) in examining early myocardial injury during percutaneous coronary intervention (PCI). METHODS: Eight-six patients who had undergone elective PCI for their coronary heart disease were enrolled in the study. The IcECG both at baseline and after procedure were recorded with an incoronary guidewire and the serum levels of cardiac troponin T (cTnT) and creatine kinase-myoglobin were measured at baseline and 8 and 24 hours after intervention. Myocardial damage was defined as serum levels of cTnT increase above the upper normal value after intervention. Cardiac events after intervention was followed up. RESULTS: Of all these 86 patients with normal serum levels of cardiac markers before the procedure, significant shift at ST-segment in IcECG during PCI was observed in 30 patients (35%, abnormal group) and no shift in the remaining 56 patients (65%, control group). All the procedures were successful. Serum levels of cTnT and creatine kinase-myoglobin were significantly higher in abnormal group than in control group after intervention (P < 0.01). The intracoronary ST-segment shift had a sensitivity of 77% and a specificity of 94% in predicting myocardial injury, with positive and negative predictive values of 90% and 86%, respectively. More cardiac events were observed in abnormal group than those in control group at a 4-week follow-up after intervention (P < 0.05) and major coronary event-free survival was significantly lower in those with post-procedural ST-segment shift in the IcECG (P < 0.05). CONCLUSION: IcECG may be a useful method for predicting myocardial injuries during PCI.


Assuntos
Eletrocardiografia/métodos , Traumatismos Cardíacos/diagnóstico , Intervenção Coronária Percutânea/efeitos adversos , Adulto , Idoso , Feminino , Traumatismos Cardíacos/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade
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