Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 51
Filtrar
1.
Anal Bioanal Chem ; 416(4): 945-957, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38051414

RESUMO

Histamine causes allergic reactions and can serve as an indicator for assessing food quality. This study designed and developed a dispersive micro solid-phase extraction (D-µSPE) method that combined the advantages of dispersive liquid-liquid extraction and solid-phase extraction (SPE). Molecularly imprinted polymers (MIPs) were employed as the solid phase in the D-µSPE method to extract histamine in wine samples. We used microwave energy to significantly reduce the synthesis time, achieving an 11.1-fold shorter synthesis time compared to the conventional MIP synthetic method. Under optimized D-µSPE conditions, our results showed that the dispersive solvent could effectively increase the adsorption performance of MIPs in wine samples by 97.7%. To improve the sensitivity of histamine detection in gas chromatography-mass spectrometry, we employed the microwave-assisted tandem derivatization method to reuse excess derivatization reagents and reduce energy consumption and reaction time. Calibration curves were constructed for wine samples spiked with 0-400 nmol histamine using the standard addition method, resulting in good linearity with a coefficient of determination of 0.999. The intra- and inter-batch relative standard deviations of the slope and intercept were < 0.7% and < 5.3%, respectively. The limits of quantitation and detection were 0.4 nmol and 0.1 nmol, respectively. The developed method was successfully applied to analyze the histamine concentration in 10 commercial wine samples. In addition, the AGREEprep tool was used to evaluate the greenness performance of the developed method, which obtained a higher score than the other reported methods.


Assuntos
Impressão Molecular , Vinho , Vinho/análise , Cromatografia Líquida de Alta Pressão/métodos , Histamina/análise , Polímeros/química , Extração em Fase Sólida/métodos , Impressão Molecular/métodos
2.
Food Chem Toxicol ; 178: 113942, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37451598

RESUMO

Food contact chemicals (FCCs) can migrate from packaging materials to food posing an issue of exposure to FCCs of toxicity concern. Compared to costly experiments, computational methods can be utilized to assess the migration potentials for various migration scenarios for further experimental investigation that can potentially accelerate the migration assessment. This study developed a nonlinear machine learning method utilizing chemical properties, material type, food type and temperature to predict chemical migration from package to food. Nine nonlinear algorithms were evaluated for their prediction performance. The ensemble model leveraging multiple algorithms provides state-of-the-art performance that is much better than previous linear regression models. The developed prediction models were subsequently applied to profile the migration potential of FCCs of high toxicity concern. The models are expected to be useful for accelerating the assessment of migration of FCCs from package to foods.


Assuntos
Contaminação de Alimentos , Embalagem de Alimentos , Contaminação de Alimentos/análise , Alimentos , Algoritmos , Aprendizado de Máquina
3.
Arch Toxicol ; 96(12): 3305-3314, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36175685

RESUMO

Exposure to neurotoxicants has been associated with Parkinson's disease (PD). Limited by the clinical variation in the signs and symptoms as well as the slow disease progression, the identification of parkinsonian neurotoxicants relies on animal models. Here, we propose an innovative in silico model for the prediction of parkinsonian neurotoxicants. The model was designed based on a validated adverse outcome pathway (AOP) for parkinsonian motor deficits initiated from the inhibition of mitochondrial complex I. The model consists of a molecular docking model for mitochondrial complex I protein to predict the molecular initiating event and a neuronal cytotoxicity Quantitative Structure-Activity Relationships (QSAR) model to predict the cellular outcome of the AOP. Four known PD-related complex I inhibitors and four non-neurotoxic chemicals were utilized to develop the threshold of the models and to validate the model, respectively. The integrated model showed 100% specificity in ruling out the non-neurotoxic chemicals. The screening of 41 neurotoxicants and complex I inhibitors with the model resulted in 16 chemicals predicted to induce parkinsonian disorder through the molecular initiating event of mitochondrial complex I inhibition. Five of them, namely cyhalothrin, deguelin, deltamethrin, diazepam, and permethrin, are cases with direct evidence linking them to parkinsonian motor deficit-related signs and symptoms. The neurotoxicant prediction model for parkinsonian motor deficits based on the AOP concept may be useful in prioritizing chemicals for further evaluations on PD potential.


Assuntos
Rotas de Resultados Adversos , Doença de Parkinson , Transtornos Parkinsonianos , Animais , Simulação de Acoplamento Molecular , Permetrina , Transtornos Parkinsonianos/induzido quimicamente , Doença de Parkinson/etiologia , Complexo I de Transporte de Elétrons/metabolismo , Diazepam
4.
PLoS One ; 17(3): e0266416, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35358291

RESUMO

BACKGROUND: Diabetic patients are at risk of severe urinary tract infections (UTIs). Due to the emerging resistance rates to fluoroquinolones and ß-lactams, we aimed to evaluate the effectiveness of ß-lactams versus fluoroquinolones as empirical therapy for diabetic patients hospitalized for UTIs. METHODS: A retrospective cohort study was conducted in a medical center in Taiwan between 2016 and 2018. Patients with type 2 diabetes, aged ≥20 and hospitalized for UTIs were enrolled. Patients with UTI diagnosis within one year before the admission, co-infections at the admission, or ≥2 pathogens in the urine cultures were excluded. The primary outcome was empiric treatment failure. RESULTS: 298 patients were followed for at least 30 days after the admission. Escherichia coli (61.07%) was the most common pathogen. The resistance rates of the pathogens to levofloxacin were 28.52% and 34.22% according to the historical Clinical and Laboratory Standards Institute (CLSI) breakpoints and the updated 2019 CLSI breakpoints, respectively. The resistance rates of ceftazidime and cefepime were 21.81% and 11.41%, respectively. Empirical ß-lactams were associated with less treatment failure compared to fluoroquinolones (adjusted OR = 0.32, 95% CI = 0.17-0.60). Beta-lactams were associated with less treatment failure than fluoroquinolones when appropriatness was determined by the pre-2019 CLSI breakpoints but not the 2019 CLSI breakpoints. CONCLUSIONS: In diabetic patients hospitalized for UTIs, ß-lactams were associated with less empiric treatment failure compared to fluoroquinolones when the resistance rate to fluoroquinolone is higher than ß-lactams. The updated 2019 CLSI breakpoint for fluoroquinolone was better than pre-2019 CLSI breakpoints to correlate with treatment outcomes for hospitalized UTIs in diabetic patients.


Assuntos
Diabetes Mellitus Tipo 2 , Infecções Urinárias , Antibacterianos/uso terapêutico , Ceftazidima/uso terapêutico , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Escherichia coli , Fluoroquinolonas/uso terapêutico , Humanos , Testes de Sensibilidade Microbiana , Estudos Retrospectivos , Resultado do Tratamento , Infecções Urinárias/complicações , Infecções Urinárias/tratamento farmacológico , beta-Lactamas/uso terapêutico
5.
Regul Toxicol Pharmacol ; 124: 104970, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34087384

RESUMO

BACKGROUND: Statin is biologically plausible in cataract development, but inconclusive associations between statin and cataract are presented in human studies. Given most early onset cataract (EOC) occurs in regions with high cholesterol composition, we therefore aimed to assess the association between statin and EOC. METHODS: A population based case-control study was performed using the Taiwan National Health Insurance Research Database (NHIRD). The case involved patients aged 20-55 years with EOC. Controls were 1:1 matched by age, gender, year of index date, and propensity score estimated from comorbidities and comedications. Statin exposure, including intensity, properties and cumulative exposure one year before the index date were tracked. The odds ratios (ORs) of EOC associated with statin were estimated by conditional logistic regression. RESULTS: A total of 4213 cases and 4213 controls were included. Statins were associated with EOC (OR = 3.257, 95% CI 2.519-4.211). The ORs of cataract was positively associated with cumulative exposure. Subgroup analysis indicated that the ORs of cataract were significant both in lipophilic (OR = 3.485, 95% CI 2.606-4.659) and hydrophilic (OR = 3.241, 95% CI 1.975-5.321) statin users. CONCLUSIONS: Statins were associated with an increased risk of cataract in young populations.


Assuntos
Catarata/epidemiologia , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Adulto , Idade de Início , Estudos de Casos e Controles , Catarata/induzido quimicamente , Bases de Dados Factuais/estatística & dados numéricos , Feminino , Humanos , Interações Hidrofóbicas e Hidrofílicas , Inibidores de Hidroximetilglutaril-CoA Redutases/química , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Taiwan/epidemiologia , Adulto Jovem
6.
Pharmaceutics ; 13(3)2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33808836

RESUMO

The aim of this study was to design oil in water (O/W) microemulsion formulations for the topical administration of azelaic acid. The permeability of azelaic acid through rat skin and the anti-inflammatory activities of the formulations were conducted to examine the efficacy of the designed formulations. Skin irritation and stability tests were also performed. The permeability of azelaic acid was significantly increased by using O/W microemulsions as carriers. The edema index of ear swelling percentage was significantly recovered by the 5% drug-loaded formulation and a 20% commercial product, demonstrating that the experimental formulation possessed comparable effect with the commercial product on the improvement of inflammation. The experimental formulation did not cause significant skin irritation compared to the negative control group. Moreover, the drug-loaded formulation also showed thermodynamic stability and chemical stability after storage for 30 days. In conclusion, the O/W microemulsion was a potential drug delivery carrier for azelaic acid topical application.

7.
J Agric Food Chem ; 69(14): 4331-4341, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33787240

RESUMO

The current approaches remain insufficient for measuring chicken egg spoilage or present analytical limitations. This study aimed to complement the existing analyses and identify novel markers using liquid chromatography-high resolution mass spectrometry-based foodomics strategies. In the discovery set, comparative untargeted metabolomics was utilized to identify marker candidates in microbially inoculated chicken eggs. Markers were annotated by spectral matching with authentic standards, experimental libraries, or in silico fragmentation. In the validation set, targeted metabolomics was employed to verify the markers in stored chicken eggs from five farms. Statistical differences at a p-value < 0.001 revealed increases in lactic and 3-hydroxybutyric acids and decreases in phosphocholine, LPE(O-18:1), LPC(16:0), and LPC(18:0) in stored eggs. Receiver operating characteristic curve analysis of the six combined markers yielded an AUC of 0.956 and a sensitivity and specificity of ∼90%. Four phospholipids were highlighted as a novel class of spoilage markers. Our findings may contribute to further industrial implementation, benefiting the quality assurance and food safety of poultry egg production.


Assuntos
Galinhas , Metabolômica , Animais , Cromatografia Líquida , Ovos , Espectrometria de Massas
8.
Regul Toxicol Pharmacol ; 119: 104815, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33159970

RESUMO

Preservatives play a vital role in cosmetics by preventing microbiological contamination for keeping products safe to use. However, a few commonly used preservatives have been suggested to be neurotoxic. Cytotoxicity to neuronal cells is commonly used as the first-tier assay for assessing chemical-induced neurotoxicity. Given the time and resources required for chemical screening, computational methods are attractive alternatives over experimental approaches in prioritizing chemicals prior to further experimental evaluations. In this study, we developed a Quantitative Structure-Activity Relationships (QSAR) model for the identification of potential neurotoxicants. A set of 681 chemicals was utilized to construct a robust prediction model using oversampling and Random Forest algorithms. Within a defined applicability domain, the independent test on 452 chemicals showed a high accuracy of 87.7%. The application of the model to 157 preservatives identified 15 chemicals potentially toxic to neuronal cells. Three of them were further validated by in vitro experiments. The results suggested that further experiments are desirable for assessing the neurotoxicity of the identified preservatives with potential neuronal cytotoxicity.


Assuntos
Modelos Teóricos , Neurônios/efeitos dos fármacos , Conservantes Farmacêuticos/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cosméticos , Humanos , Conservantes Farmacêuticos/química , Relação Quantitativa Estrutura-Atividade
9.
Molecules ; 25(20)2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33053784

RESUMO

This study explores the amounts of common chemical ultraviolet (UV) filters (i.e., avobenzone, bemotrizinol, ethylhexyl triazone, octocrylene, and octyl methoxycinnamate) in cosmetics and the human stratum corneum. An ultrasound-vortex-assisted dispersive liquid-liquid microextraction (US-VA-DLLME) method with a high-performance liquid chromatography-diode array detector was used to analyze UV filters. A bio-derived solvent (i.e., anisole) was used as the extractant in the US-VA-DLLME procedure, along with methanol as the dispersant, a vortexing time of 4 min, and ultrasonication for 3 min. The mass-transfer rate of the extraction process was enhanced due to vortex-ultrasound combination. Various C18 end-capped columns were used to investigate the separation characteristics of the UV filters, with XBridge BEH or CORTECS selected as the separation column. Calibration curves were constructed in the 0.05-5 µg/mL (all filters except octocrylene) and 0.1-10 µg/mL (octocrylene) ranges, and excellent analytical linearities with coefficients of determination (r2) above 0.998. The developed method was successfully used to analyze sunscreen. Moreover, experiments were designed to simulate the sunscreen-usage habits of consumers, and the cup method was used to extract UV filters from the human stratum corneum. The results suggest that a makeup remover should be employed to remove water-in-oil sunscreens from skin.


Assuntos
Cosméticos , Epiderme/química , Microextração em Fase Líquida/métodos , Ondas Ultrassônicas , Cromatografia Líquida de Alta Pressão , Humanos , Solventes
10.
Analyst ; 145(21): 7072, 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-32901639

RESUMO

Correction for 'Progress of electrospray ionization and rapid evaporative ionization mass spectrometric techniques for the broad-range identification of microorganisms' by Suresh Kumar Kailasa et al., Analyst, 2019, 144, 1073-1103, DOI: 10.1039/C8AN02034E.

11.
Asia Pac Psychiatry ; 12(4): e12404, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32715665

RESUMO

INTRODUCTION: End-stage renal disease is a serious public health issue. The objective of this retrospective cohort study was to assess the association between hemodialysis and cognitive impairment, while controlling for age, sex, residence, and comorbidities. METHODS: This study assesses the risk of cognitive impairment among a nationwide cohort of new hemodialysis patients derived from the NHIRD. RESULTS: A total of 4330 patients were assigned to the dialysis group and 17 320 patients were assigned to the control group. A total of 2103 of the patients developed cognitive impairment within 2 years after the date of dialysis initiation. Patients who developed cognitive impairment were older (69.85 ± 11.56) than their counterparts who did not develop cognitive impairment (58.58 ± 14.77; P < .001). The log-rank test of Kaplan-Meier analysis revealed a higher risk of cognitive impairment in the hemodialysis group than in the non-hemodialysis group (P < .001). The interval between dialysis initiation and the onset of cognitive impairment was 98.66 ± 46.39 months among non-dialysis subjects and 53.45 ± 41.90 months among dialysis subjects, and the between-group difference was significant (P < .001). The Cox Proportional Hazard Model revealed that after controlling for gender, age, residence, and comorbidities, hemodialysis was shown to have a significant impact on cognitive impairment (Hazard Ratio [HR]: 1.44; 95% confidence interval [CI]: 1.29-1.60). Furthermore, the risk of developing cognitive impairment increased with age (HR: 1.07; 95% CI: 1.06-1.08). DISCUSSION: Hemodialysis was associated with cognitive impairment. There was a significant association between age and cognitive impairment, regardless of the comorbidities prior to hemodialysis. There was no evidence of an association between comorbidities and cognitive impairment after beginning hemodialysis.


Assuntos
Disfunção Cognitiva/epidemiologia , Falência Renal Crônica/epidemiologia , Falência Renal Crônica/terapia , Diálise Renal/estatística & dados numéricos , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Bases de Dados Factuais , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taiwan/epidemiologia
12.
Molecules ; 25(15)2020 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-32722482

RESUMO

One new dibenzocycloheptene, validinol (1), and one butanolide firstly isolated from the natural source, validinolide (2), together with 17 known compounds were isolated from the stem of Cinnamomum validinerve. Among the isolates, lincomolide A (3), secosubamolide (7), and cinnamtannin B1 (19) exhibited potent inhibition on both superoxide anion generation (IC50 values of 2.98 ± 0.3 µM, 4.37 ± 0.38 µM, and 2.20 ± 0.3 µM, respectively) and elastase release (IC50 values of 3.96 ± 0.31 µM, 3.04 ± 0.23 µM, and 4.64 ± 0.71 µM, respectively) by human neutrophils. In addition, isophilippinolide A (6), secosubamolide (7), and cinnamtannin B1 (19) showed bacteriostatic effects against Propionibacterium acnes in in vitro study, with minimal inhibitory concentration (MIC) values at 16 µg/mL, 16 µg/mL, and 500 µg/mL, respectively. Further investigations using the in vivo ear P. acnes infection model showed that the intraperitoneal administration of the major component cinnamtannin B1 (19) reduced immune cell infiltration and pro-inflammatory cytokines TNF-α and IL-6 at the infection sites. The results demonstrated the potential of cinnamtannin B1 (19) for acne therapy. In summary, these results demonstrated the anti-inflammatory potentials of Formosan C. validinerve during bacterial infections.


Assuntos
Acne Vulgar/tratamento farmacológico , Cinnamomum/química , Inflamação/tratamento farmacológico , Extratos Vegetais/farmacologia , Acne Vulgar/microbiologia , Acne Vulgar/patologia , Antibacterianos/química , Antibacterianos/farmacologia , Humanos , Inflamação/metabolismo , Inflamação/microbiologia , Inflamação/patologia , Testes de Sensibilidade Microbiana , Monócitos/efeitos dos fármacos , Monócitos/microbiologia , Extratos Vegetais/química , Caules de Planta/química , Propionibacterium acnes/efeitos dos fármacos , Propionibacterium acnes/patogenicidade
13.
Artigo em Inglês | MEDLINE | ID: mdl-32560183

RESUMO

Non-genotoxic hepatocarcinogens (NGHCs) can only be confirmed by 2-year rodent studies. Toxicogenomics (TGx) approaches using gene expression profiles from short-term animal studies could enable early assessment of NGHCs. However, high variance in the modulation of the genes had been noted among exposure styles and datasets. Expanding from our previous strategy in identifying consensus biomarkers in multiple experiments, we aimed to identify time-invariant biomarkers for NGHCs in short-term exposure styles and validate their applicability to long-term exposure styles. In this study, nine time-invariant biomarkers, namely A2m, Akr7a3, Aqp7, Ca3, Cdc2a, Cdkn3, Cyp2c11, Ntf3, and Sds, were identified from four large-scale microarray datasets. Machine learning techniques were subsequently employed to assess the prediction performance of the biomarkers. The biomarker set along with the Random Forest models gave the highest median area under the receiver operating characteristic curve (AUC) of 0.824 and a low interquartile range (IQR) variance of 0.036 based on a leave-one-out cross-validation. The application of the models to the external validation datasets achieved high AUC values of greater than or equal to 0.857. Enrichment analysis of the biomarkers inferred the involvement of chronic inflammatory diseases such as liver cirrhosis, fibrosis, and hepatocellular carcinoma in NGHCs. The time-invariant biomarkers provided a robust alternative for NGHC prediction.


Assuntos
Carcinógenos , Neoplasias Hepáticas , Animais , Biomarcadores , Carcinógenos/análise , Carcinógenos/toxicidade , Perfilação da Expressão Gênica , Neoplasias Hepáticas/induzido quimicamente , Toxicogenética
14.
Database (Oxford) ; 20202020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32539087

RESUMO

Exposure to toxic substances in the environment is one of the most important causes of cancer. However, the time-consuming process for the identification and characterization of carcinogens is not applicable to a huge amount of testing chemicals. The data gaps make the carcinogenic risk uncontrollable. An efficient and effective way of prioritizing chemicals of carcinogenic concern with interpretable mechanism information is highly desirable. This study presents a curation work for genes and pathways associated with 11 hallmarks of cancer (HOCs) reported by the Halifax Project. To demonstrate the usefulness of the curated HOC data, the interacting HOC genes and affected HOC pathways of chemicals of the three carcinogen lists from IARC, NTP and EPA were analyzed using the in silico toxicogenomics ChemDIS system. Results showed that a higher number of affected HOCs were observed for known carcinogens than the other chemicals. The curated HOC data is expected to be useful for prioritizing chemicals of carcinogenic concern. Database URL: The HOC database is available at https://github.com/hocdb-KMU-TMU/hocdb and the website of Database journal as Supplementary Data.


Assuntos
Carcinógenos , Simulação por Computador , Curadoria de Dados , Genes Neoplásicos/genética , Neoplasias , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Carcinógenos/classificação , Carcinógenos/toxicidade , Bases de Dados Factuais , Humanos , Neoplasias/induzido quimicamente , Neoplasias/genética , Toxicogenética
15.
Int J Antimicrob Agents ; 55(3): 105889, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31923573

RESUMO

Colistin is the last-resort antimicrobial agent against infections caused by multidrug-resistance Gram-negative bacteria (MDR-GNB). However, a differing risk of colistin-associated acute kidney injury (CA-AKI) has been demonstrated without affecting mortality, thus the association and its importance needs to be questioned. To assess the impact of this adverse effect, a meta-analysis comparing colistin with other antibiotics in treating MDR-GNB infections was conducted. The PubMed, Embase and Cochrane Library electronic databases were searched up to 31 December 2018 for cohort studies and randomised controlled trials with at least two arms with one arm containing colistin-based treatment. The primary endpoint was the incidence of AKI. The secondary endpoint was 30-day all-cause mortality. A total of 34 studies, including 26 regarding colistin-based therapy versus other antibiotics and 9 regarding colistin monotherapy versus combination therapy, were included. The incidence of CA-AKI was 32.3%. Colistin was associated with an 82% higher incidence of AKI than other antibiotics [odd ratio (OR) = 1.82, 95% confidence interval (CI) 1.13-2.92; P = 0.01]. Most CA-AKI events were mild and reversible without a higher rate of mortality or the requirement for renal replacement therapy (RRT). Only 1.0% of patients required RRT for > 4 weeks. Compared with colistin monotherapy, combination therapy was associated with a significantly lower incidence of AKI (OR = 1.46, 95% CI 1.10-1.94; P = 0.009), particularly in combination with a carbapenem (OR = 1.97, 95% CI 1.30-2.99; P = 0.001). In conclusion, CA-AKI might not be an important limitation of colistin in MDR-GNB therapy.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Antibacterianos/administração & dosagem , Colistina/efeitos adversos , Bactérias Gram-Negativas/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Injúria Renal Aguda/mortalidade , Injúria Renal Aguda/terapia , Adulto , Antibacterianos/uso terapêutico , Carbapenêmicos/farmacologia , Carbapenêmicos/uso terapêutico , Estudos de Coortes , Colistina/uso terapêutico , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Humanos , Incidência , Terapia de Substituição Renal
16.
PeerJ ; 8: e10548, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33391878

RESUMO

BACKGROUND: Rosacea is a common inflammatory disease of facial skin. Dysregulation of innate immunity with enhanced inflammation and increased abundance of LL-37 at the epidermal site is a characteristic feature of rosacea. Cinnamtannin B1 (CB1) is a condensed tannin with anti-inflammatory and anti-microbial activities. The aims of the study were to evaluate the potential of CB1 as a therapy for rosacea and to characterize the potential mechanisms of action. METHODS: We intraperitoneally administered 20 mg/kg CB1 once daily for 2 days into the LL-37-induced mouse model of rosacea. The effects of CB1 in vivo were evaluated by the observations of lesions, histology, immunohistochemistry, and the transcription and translation of pro-inflammatory cytokines and chemokines. Human keratinocyte HaCaT and monocyte THP-1 were used to characterize the effects of CB1 on LL-37-induced inflammation in vitro. The changes in pro-inflammatory chemokine interleukin-8 (IL-8) were quantitated by enzyme-linked immunosorbent assay (ELISA), and the expressions of genes involved were determined by Western blotting. RESULTS: CB1 attenuated local redness, inflammation, and neutrophil recruitment in the mouse model of rosacea in vivo. CB1 suppressed myeloperoxidase (MPO) and macrophage inflammatory protein 2 (MIP-2) production, a functional homolog of interleukin-8 (IL-8), at the lesions. In vitro experiments confirmed that CB1 reversed the LL-37-induced IL-8 production in human keratinocytes HaCaT and monocyte THP-1 cells. CB1 inhibited IL-8 production through downregulating the phosphorylation of extracellular signal-regulated kinase (ERK) in the mitogen-activated protein kinase (MAPK) pathway. CONCLUSION: CB1 attenuated LL-37-induced inflammation, specifically IL-8 production, through inhibiting the phosphorylation of ERK. CB1 has potential as a treatment for rosacea.

17.
Talanta ; 199: 464-471, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30952285

RESUMO

In this study, an ecofriendly analytical method was developed for determining glutathione (GSH) levels in biomatrix samples. 9-(bromomethyl)acridine was used for the first time as a derivatization reagent in GSH analysis. Microwave-assisted derivatization reduced the reaction time to 1 min. After derivatization, coacervative extraction was employed to extract GSH derivative from the complex biomatrix and to increase sensitivity. Because the negatively charged group of the GSH derivative was neutralized by the extracting agent Aliquat 336, aggregates formed without any coacervating agents. Furthermore, capillary liquid chromatography coupled with ultraviolet detection was applied to decrease waste generation and increase selectivity. This method successfully quantified GSH levels in various biomatrices, including erythrocytes, HaCaT cells, BALB/3T3 cells, and 3T3-L1 fibroblasts. This method only required a low sample volume (≤10 µL). A standard addition method was utilized to spike the biomatrix samples with 0-4.8 nmol GSH to construct calibration curves. The proposed method performed well, with a determination coefficient of 0.999 and relative standard deviations of less than 6.59% for the slope and the intercept, as determined by linear regression analysis. The limit of detection of GSH in the standard solution was 800 nM or 0.4 pmol. Compared to non-derivatized GSH, the proposed method for detecting derivatized GSH provides 750-fold greater sensitivity.

18.
Analyst ; 144(4): 1073-1103, 2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30698588

RESUMO

Several non-culture molecular (multiplex polymerase chain reaction assays, DNA microarrays, massive parallel DNA sequencing, in situ hybridization, microbiome profiling, and molecular typing of pathogens) and analytical (electrophoresis, gel electrophoresis, surface-enhanced Raman scattering, and mass spectrometry) tools have been developed in recent years for the identification of bacteria and diagnosis of bacterial infections from clinical samples. Among mass spectrometric techniques, electrospray ionization (ESI) and rapid evaporative ionization (REI) mass spectrometric (MS) techniques have attracted much attention in the identification of microorganisms (bacteria, fungi, and viruses), and in the diagnosis of various bacterial infections. This review highlights the developed ESI-MS-based methods, including polymerase chain reaction (PCR) combined with ESI-MS and capillary electrophoresis (CE) and liquid chromatography (LC)-ESI-MS, for the identification of microorganisms (pathogenic bacteria, fungi, and viruses) in various samples. Recent applications of ESI- and REI-MS in identifying pathogenic bacteria are depicted in tables, and some significant findings are summarized.


Assuntos
Bactérias/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray/métodos , Bactérias/química , Humanos , Volatilização
19.
Anal Chem ; 89(20): 10883-10888, 2017 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-28976728

RESUMO

Reactive oxygen species (ROS) can induce oxidative stress and are associated with cell death and chronic diseases in organisms. In the treatment of disease, drugs that induce ROS are associated with many side effects and unpleasant symptoms. Therefore, during the assessment of new drugs and candidate compounds, ROS generation is an issue of concern, because ROS can modify proteins, lipids, and nucleic acids within organisms and alter their biological functions. In this work, we designed a peptide-based probe for the rapid (<10 min) high-throughput survey of oxidative stress induced by clinical drugs at the microliter level. Using menadione and H2O2 as positive controls, just 100 µg/mL of the test compound and 100 µg/mL of the probe were sufficient to effectively monitor the generation of ROS, which is important as many active compounds are rare and difficult to isolate or purify. This in vitro evaluation could be used to effectively generate preliminary data before pharmacologically active candidate compounds are processed in cell-line or animal tests. Furthermore, we demonstrated that this peptide probe successfully detects ROS in biological samples.


Assuntos
Peptídeos/química , Espécies Reativas de Oxigênio/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Linhagem Celular , Humanos , Peróxido de Hidrogênio/análise , Peróxido de Hidrogênio/química , Oxirredução , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo , Vitamina K 3/química
20.
J Immunol Res ; 2017: 3529859, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28781969

RESUMO

Neolitsea species, medicinal plants belonging to Lauraceae, contain rich alkaloids, steroids, sesquiterpenoids, and triterpenoids which possess antimicrobial, antioxidant, and anti-inflammatory bioactivities. However, species differences in the immunomodulatory effects and evidence pertaining to the effects of Neolitsea species on adaptive immunity are scarce. This study aimed to evaluate the immunomodulatory properties of ten Taiwanese Neolitsea plants on T helper (Th) cell functionality, especially Th1 and Th2. Most of the 29 crude extracts of Neolitsea were not toxic to splenocytes, except N. buisanensis roots. N. aciculata and N. villosa leaf extracts possessed differential immunomodulatory effects on Th1/Th2 balance. N. aciculata var. variabillima and N. hiiranensis leaf extracts attenuated both Th1 and Th2 cytokines while N. konishii dramatically suppressed IFN-γ production. As N. aciculata var. variabillima and N. konishii leaf extracts significantly attenuated Th1 functionality, we further evaluated their effects on CD4 cells under CD3/CD28 stimulation. N. aciculata var. variabillima significantly suppressed IFN-γ, IL-10, and IL-17, demonstrating the broad suppressive effects on T helper cells; N. konishii significantly suppressed IFN-γ and IL-10 production, while the production of IL-17 was not altered. Collectively, these data demonstrated that leaf extracts of Taiwanese Neolitsea species contain phytochemicals with potentials to be developed as selective immunomodulators.


Assuntos
Citocinas/biossíntese , Medicamentos de Ervas Chinesas/farmacologia , Imunomodulação , Lauraceae/química , Células Th1/imunologia , Células Th2/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Humanos , Interferon gama/biossíntese , Interleucina-10/biossíntese , Interleucina-17/biossíntese , Interleucina-17/metabolismo , Camundongos , Baço/citologia , Baço/efeitos dos fármacos , Células Th1/efeitos dos fármacos , Equilíbrio Th1-Th2 , Células Th2/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...