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1.
Stat Med ; 43(18): 3403-3416, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38847215

RESUMO

Conventional pharmacokinetic (PK) bioequivalence (BE) studies aim to compare the rate and extent of drug absorption from a test (T) and reference (R) product using non-compartmental analysis (NCA) and the two one-sided test (TOST). Recently published regulatory guidance recommends alternative model-based (MB) approaches for BE assessment when NCA is challenging, as for long-acting injectables and products which require sparse PK sampling. However, our previous research on MB-TOST approaches showed that model misspecification can lead to inflated type I error. The objective of this research was to compare the performance of model selection (MS) on R product arm data and model averaging (MA) from a pool of candidate structural PK models in MBBE studies with sparse sampling. Our simulation study was inspired by a real case BE study using a two-way crossover design. PK data were simulated using three structural models under the null hypothesis and one model under the alternative hypothesis. MB-TOST was applied either using each of the five candidate models or following MS and MA with or without the simulated model in the pool. Assuming T and R have the same PK model, our simulation shows that following MS and MA, MB-TOST controls type I error rates at or below 0.05 and attains similar or even higher power than when using the simulated model. Thus, we propose to use MS prior to MB-TOST for BE studies with sparse PK sampling and to consider MA when candidate models have similar Akaike information criterion.


Assuntos
Simulação por Computador , Estudos Cross-Over , Modelos Estatísticos , Equivalência Terapêutica , Humanos , Farmacocinética
2.
Anal Chem ; 95(24): 9244-9251, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37285171

RESUMO

Identification of α-thalassemia silent carriers is challenging with conventional phenotype-based screening methods. A liquid chromatography tandem mass spectrometry (LC-MS/MS)-based approach may offer novel biomarkers to address this conundrum. In this study, we collected dried blood spot samples from individuals with three α-thalassemia subtypes for biomarker discovery and validation. We observed differential expression patterns of hemoglobin subunits among various α-thalassemia subtypes and normal controls through proteomic profiling of 51 samples in the discovery phase. Then, we developed and optimized a multiple reaction monitoring (MRM) assay to measure all detectable hemoglobin subunits. The validation phase was conducted in a cohort of 462 samples. Among the measured hemoglobin subunits, subunit µ was significantly upregulated in all the α-thalassemia groups with distinct fold changes. The hemoglobin subunit µ exhibits great potential as a novel biomarker for α-thalassemia, especially for silent α-thalassemia. We constructed predictive models based on the concentrations of hemoglobin subunits and their ratios to classify the various subtypes of α-thalassemia. In the binary classification problems of silent α-thalassemia vs normal, non-deletional α-thalassemia vs normal, and deletional α-thalassemia vs normal, the best performance of the models achieved average ROCAUCs of 0.9505, 0.9430, and 0.9976 in the cross-validation, respectively. In the multiclass model, the best performance achieved an average ROCAUC of 0.9290 in cross-validation. The performance of our MRM assay and models demonstrated that the hemoglobin subunit µ would play a vital role in screening silent α-thalassemia in clinical practice.


Assuntos
Subunidades de Hemoglobina , Talassemia alfa , Humanos , Cromatografia Líquida , Espectrometria de Massas em Tandem/métodos , Talassemia alfa/diagnóstico , Proteômica , Biomarcadores
3.
Biochem Biophys Res Commun ; 683: 149110, 2023 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-37866110

RESUMO

Sperm is the key media between the father's aberrant exposure and the offspring's phenotype. Whether paternal hypertension affects offspring through sperm epigenetics remains to be explored. To investigate the underlying mechanisms, we constructed a hypertensive mice model induced by drinking l-NAME and found that spermatocytes and spermatids in the testis were increased significantly after l-NAME treatment. The sequencing of sperm showed that tsRNA profiles changed with 315 tsRNAs (195 up-regulated and 120 down-regulated) altered. Meanwhile, KEGG pathway analysis showed that the target genes of these altered tsRNAs were involved in influencing some important signaling pathways, such as the cAMP signaling path, the mTOR signaling path, the Hippo signaling path, and the Ras signaling path. Bioinformatics of tsRNA-miRNA-mRNA pathway interactions revealed several ceRNA mechanisms, such as tsRNA-00051, the ceRNA of miR-128-1-5p, co-targeting Agap1. This study provides evidence for enriching and further understanding the pathophysiology and paternal epigenetic mechanisms of testicular reproduction, as well as contributing to a rethinking of the transgenerational reprogramming mechanisms of paternal exposure in hypertension.


Assuntos
Sêmen , Espermatozoides , Masculino , Camundongos , Animais , NG-Nitroarginina Metil Éster , Espermatozoides/metabolismo , Espermatogênese/genética , Testículo/metabolismo
4.
Biostatistics ; 23(1): 314-327, 2022 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-32696053

RESUMO

The classical approach to analyze pharmacokinetic (PK) data in bioequivalence studies aiming to compare two different formulations is to perform noncompartmental analysis (NCA) followed by two one-sided tests (TOST). In this regard, the PK parameters area under the curve (AUC) and $C_{\max}$ are obtained for both treatment groups and their geometric mean ratios are considered. According to current guidelines by the U.S. Food and Drug Administration and the European Medicines Agency, the formulations are declared to be sufficiently similar if the $90\%$ confidence interval for these ratios falls between $0.8$ and $1.25 $. As NCA is not a reliable approach in case of sparse designs, a model-based alternative has already been proposed for the estimation of $\rm AUC$ and $C_{\max}$ using nonlinear mixed effects models. Here we propose another, more powerful test than the TOST and demonstrate its superiority through a simulation study both for NCA and model-based approaches. For products with high variability on PK parameters, this method appears to have closer type I errors to the conventionally accepted significance level of $0.05$, suggesting its potential use in situations where conventional bioequivalence analysis is not applicable.


Assuntos
Dinâmica não Linear , Área Sob a Curva , Simulação por Computador , Estudos Cross-Over , Humanos , Equivalência Terapêutica
5.
J Pharmacokinet Pharmacodyn ; 49(5): 557-577, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36112338

RESUMO

This article evaluates the performance of pharmacokinetic (PK) equivalence testing between two formulations of a drug through the Two-One Sided Tests (TOST) by a model-based approach (MB-TOST), as an alternative to the classical non-compartmental approach (NCA-TOST), for a sparse design with a few time points per subject. We focused on the impact of model misspecification and the relevance of model selection for the reference data. We first analysed PK data from phase I studies of gantenerumab, a monoclonal antibody for the treatment of Alzheimer's disease. Using the original rich sample data, we compared MB-TOST to NCA-TOST for validation. Then, the analysis was repeated on a sparse subset of the original data with MB-TOST. This analysis inspired a simulation study with rich and sparse designs. With rich designs, we compared NCA-TOST and MB-TOST in terms of type I error and study power. With both designs, we explored the impact of misspecifying the model on the performance of MB-TOST and adding a model selection step. Using the observed data, the results of both approaches were in general concordance. MB-TOST results were robust with sparse designs when the underlying PK structural model was correctly specified. Using the simulated data with a rich design, the type I error of NCA-TOST was close to the nominal level. When using the simulated model, the type I error of MB-TOST was controlled on rich and sparse designs, but using a misspecified model led to inflated type I errors. Adding a model selection step on the reference data reduced the inflation. MB-TOST appears as a robust alternative to NCA-TOST, provided that the PK model is correctly specified and the test drug has the same PK structural model as the reference drug.


Assuntos
Anticorpos Monoclonais , Simulação por Computador
6.
Analyst ; 145(6): 2357-2366, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32031196

RESUMO

Fe2+ is a trace metal ion required by the human body, and its abnormal metabolism can cause serious diseases. Herein, we report the development of a highly efficient "ON-OFF" fluorescent probe based on carbon dots (CDs), prepared by a simple one-step hydrothermal method. The CDs exhibited exceptional water dispersibility and stability, superior luminescence performance and low cytotoxicity. The fluorescence could be efficiently quenched by Fe2+ through an electronic transfer process. And under the optimized experimental conditions, this probe shows excellent selectivity and high sensitivity towards Fe2+ with a detection limit of 51 nmol. More interestingly, this probe could realize the visual detection of Fe2+ when Fe3+ and Cu2+ ions were efficiently shielded by tartaric acid in the presence of ascorbic acid. Furthermore, the developed fluorescent probe has been successfully applied for the detection of Fe2+ in tap water and BSA solution as well as for the biosensing of Fe2+ in living cells.


Assuntos
Corantes Fluorescentes/química , Ferro/análise , Pontos Quânticos/química , Carbono/química , Carbono/toxicidade , Água Potável/análise , Corantes Fluorescentes/toxicidade , Humanos , Limite de Detecção , Células MCF-7 , Microscopia de Fluorescência/métodos , Pontos Quânticos/toxicidade , Espectrometria de Fluorescência/métodos
7.
Cell Biol Int ; 43(7): 770-780, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31026365

RESUMO

Acute respiratory distress syndrome (ARDS) is an acute, severe, and refractory pulmonary inflammation with high morbidity and mortality. Excessive activation of fibroblast during the fibroproliferative phase plays a pivotal role in the prognosis of ARDS. Our previous study demonstrated that the vasoactive intestinal peptide (VIP) is mediated by lentivirus attenuates lipopolysaccharide (LPS)-induced ARDS in a murine model, and VIP inhibits the release of interleukin-17A (IL-17A) from activation macrophages. However, the effects of VIP on the activation of murine fibroblast and expression of IL-17 receptor (IL-17R) in ARDS remain unclear. Here, a mouse model of ARDS was established by an intratracheal injection of LPS. We found that the gene expression of col3a1 and hydroxyproline contents in the lungs were significantly increased 24 h after LPS injection. IL-17RC rather than IL-17RA was increased in the lungs of mice with ARDS. In vitro, LPS activated NIH3T3 cells, which was suppressed by VIP in a dose-dependent manner. In detail, VIP reduced the hydroxyproline content and col3a1 messenger RNA induced by LPS in NIH3T3 cells, as well as the expression of α-smooth muscle actin. Furthermore, we found that VIP inhibited the expression of IL-17R in the lungs of mice with ARDS and NIH3T3 cells stimulated with LPS, which was partly inhibited by antagonists of protein kinase A and protein kinase C. Taken together, our results demonstrated that VIP inhibited the activation of fibroblast via downregulation of IL-17RC, which may contribute to the protective effects of VIP against ARDS in mice.


Assuntos
Fibroblastos/imunologia , Receptores de Interleucina/imunologia , Síndrome do Desconforto Respiratório/imunologia , Transdução de Sinais/efeitos dos fármacos , Peptídeo Intestinal Vasoativo , Actinas/metabolismo , Animais , Colágeno Tipo III/metabolismo , Modelos Animais de Doenças , Hidroxiprolina/metabolismo , Lipopolissacarídeos/química , Masculino , Camundongos , Células NIH 3T3 , Inibidores de Proteínas Quinases/farmacologia , Receptores de Interleucina-17/imunologia , Peptídeo Intestinal Vasoativo/farmacologia , Peptídeo Intestinal Vasoativo/fisiologia
8.
Kidney Blood Press Res ; 44(1): 133-148, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30808832

RESUMO

BACKGROUND/AIMS: Paternal exposure to adverse environmental conditions can act on offspring's phenotype and influence offspring's later life disease risk. Our study was designed to examine the effect of feeding male rats before mating a high-fat, high-sucrose and high-salt diet (HFSSD) over two generations (F0 and F1) on their offspring's (F2) liver function and gut microbiome composition. METHODS: Male F0 rats and male F1 rats were fed either control diet or HFSSD before mating. Liver function of F2 offspring was investigated, and their gut microbiome composition was analyzed by 16S rRNA gene sequencing in the F2 offspring of rats whose fathers and grandfathers were fed with control diet (CD) (F0CD+F1CD-F2 group) or HFSSD prior to mating (F0HD+F1HD-F2 group). RESULTS: F2 offspring had higher serum aspartate aminotransferase activity (female, p < 0.05 and male, p < 0.01 respectively) compared with control. Shannon indexes of gut microbiota indicated a significantly higher diversity in the female F0HD+F1HD-F2 as compared to F0CD+F1CD-F2 female offspring (p < 0.01). The dominant phyla of all the groups were Bacteroidetes, Firmicutes and Proteobacteria. There were significant differences in gut bacterial community composition at phyla and genus level between the F0CD+F1CD-F2 and F0HD+F1HD-F2. Furthermore, the variation in the relative abundance (percentage) of bacterial genus in the F2 offspring was associated with liver function alterations induced by a paternal pre-conceptional unhealthy diet. Male F0HD+F1HD-F2 offspring had higher serum cholesterol, high density lipoproteins as well as low density lipoproteins concentrations compared to the corresponding male control rats. CONCLUSION: Taken together, our findings suggested that a paternal pre-conceptional unhealthy diet predisposes the offspring to mild liver function alterations and alterations of gut microbiota in later life. Effects on lipids were sex-specific and only seen in male offspring.


Assuntos
Lipídeos/análise , Fígado/fisiologia , Comportamento Paterno/fisiologia , Animais , Dieta Hiperlipídica , Feminino , Microbioma Gastrointestinal , Masculino , Gravidez , Ratos , Fatores Sexuais
9.
Environ Res ; 177: 108621, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31421450

RESUMO

2,4,6-trinitrophenol (TNP) is environmentally deleterious substance that has been of pressing societal concern. Therefore, developing a convenient and reliable platforms for its fast and efficient detection is of paramount importance from security point of view. Herein, amphiphilic fluorescent carbon dots (CDs) were prepared by a simple solvothermal method. CDs exhibit high selectivity and sensitivity on TNP in the polar and apolar solvent and even natural water samples. Moreover, the simple and portable indicator paper can be prepared conveniently and used for sensing TNP visually with high sensitivity and fast response. Research findings obtained from this study would assist in the development of portable devices for the on-site and real-time detection of environmental hazards.


Assuntos
Carbono , Poluentes Ambientais/análise , Substâncias Explosivas/análise , Picratos/análise , Pontos Quânticos , Monitoramento Ambiental , Corantes Fluorescentes
10.
Diabetologia ; 61(8): 1862-1876, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29777263

RESUMO

AIMS/HYPOTHESIS: Paternal high-fat diet prior to mating programmes impaired glucose tolerance in female offspring. We examined whether the metabolic consequences in offspring could be abolished by folate treatment of either the male rats before mating or the corresponding female rats during pregnancy. METHODS: Male F0 rats were fed either control diet or high-fat, high-sucrose and high-salt diet (HFSSD), with or without folate, before mating. Male rats were mated with control-diet-fed dams. After mating, the F0 dams were fed control diet with or without folate during pregnancy. RESULTS: Male, but not female offspring of HFSSD-fed founders were heavier than those of control-diet-fed counterparts (p < 0.05 and p = 0.066 in males and females, respectively). Both male and female offspring of HFSSD-fed founders were longer compared with control (p < 0.01 for both sexes). Folate treatment of the pregnant dams abolished the effect of the paternal diet on the offspring's body length (p Ë‚ 0.05). Female offspring of HFSSD-fed founders developed impaired glucose tolerance, which was restored by folate treatment of the dams during pregnancy. The beta cell density per pancreatic islet was decreased in offspring of HFSSD-fed rats (-20% in male and -15% in female F1 offspring, p Ë‚ 0.001 vs controls). Folate treatment significantly increased the beta cell density (4.3% and 3.3% after folate supplementation given to dams and founders, respectively, p Ë‚ 0.05 vs the offspring of HFSSD-fed male rats). Changes in liver connective tissue of female offspring of HFSSD-fed founders were ameliorated by treatment of dams with folate (p Ë‚ 0.01). Hepatic Ppara gene expression was upregulated in female offspring only (1.51-fold, p Ë‚ 0.05) and was restored in the female offspring by folate treatment (p Ë‚ 0.05). We observed an increase in hepatic Lcn2 and Tmcc2 expression in female offspring born to male rats exposed to an unhealthy diet during spermatogenesis before mating (p Ë‚ 0.05 vs controls). Folate treatment of the corresponding dams during pregnancy abolished this effect (p Ë‚ 0.05). Analysis of DNA methylation levels of CpG islands in the Ppara, Lcn2 and Tmcc2 promoter regions revealed that the paternal unhealthy diet induced alterations in the methylation pattern. These patterns were also affected by folate treatment. Total liver DNA methylation was increased by 1.52-fold in female offspring born to male rats on an unhealthy diet prior to mating (p Ë‚ 0.05). This effect was abolished by folate treatment during pregnancy (p Ë‚ 0.05 vs the offspring of HFSSD-fed male rats). CONCLUSIONS/INTERPRETATION: Folate treatment of pregnant dams restores effects on female offspring's glucose metabolism induced by pre-conception male founder HFSSD.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Dieta Hiperlipídica/efeitos adversos , Ácido Fólico/uso terapêutico , Prenhez , Ração Animal , Animais , Metilação de DNA , Feminino , Perfilação da Expressão Gênica , Teste de Tolerância a Glucose , Fígado/embriologia , Fígado/metabolismo , Masculino , Pâncreas/metabolismo , Gravidez , RNA/análise , Ratos , Ratos Sprague-Dawley , Cloreto de Sódio/química , Espermatogênese , Sacarose/química , Triglicerídeos/metabolismo , Regulação para Cima
11.
Anal Chem ; 90(14): 8629-8634, 2018 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-29911858

RESUMO

As one of the key initiators of the base excision repair process, uracil-DNA glycosylase (UDG) plays an important role in maintaining genomic integrity. It has been found that aberrant expression of UDG is associated with a variety of diseases. Thus, accurate and sensitive detection of UDG activity is of critical significance for biomedical research and early clinical diagnosis. Here, we developed a novel fluorescent sensing platform for UDG activity detection based on a terminal deoxynucleotidyl transferase (TdT) and T7 exonuclease (T7 Exo)-aided recycling amplification strategy. In this strategy, only two DNA oligonucleotides (DNA substrate containing one uracil base and Poly dT probe labeled with a fluorophore/quencher pair) are used. UDG catalyzes the removal of uracil base from the enclosed dumbbell-shape DNA substrate to give an apyrimidinic site, at which the substrate oligonucleotide is cleaved by endonuclease IV. The released 3'-end can be elongated by TdT to form a long deoxyadenine-rich (Poly dA) tail, which may be used as a recyclable template to initiate T7 Exo-mediated hybridization-digestion cycles of the Poly dT probe, giving a significantly enhanced fluorescence output. The proposed UDG-sensing strategy showed excellent selectivity and high sensitivity with a detection limit of 1.5 × 10-4 U/mL. The sensing platform was also demonstrated to work well for UDG inhibitor screening and inhibitory activity evaluation, thus holding great potential in UDG-related disease diagnosis and drug discovery. The proposed strategy can be easily used for the detection of other DNA repair-related enzymes by simply changing the recognition site in DNA substrate and might also be extended to the analysis of some DNA/RNA-processing enzymes, including restriction endonuclease, DNA methyltransferase, polynucleotide kinase, and so on.


Assuntos
DNA Nucleotidilexotransferase/metabolismo , Ensaios Enzimáticos/métodos , Exodesoxirribonucleases/metabolismo , Uracila-DNA Glicosidase/análise , Técnicas Biossensoriais/métodos , Células HeLa , Humanos , Limite de Detecção , Hibridização de Ácido Nucleico/métodos , Uracila-DNA Glicosidase/metabolismo
12.
Analyst ; 143(23): 5834-5840, 2018 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-30374496

RESUMO

Although hypochlorite (ClO-) and bisulfite (HSO3-) play important roles in the biological immune system and the aging process of living organisms, they are also classified as a third type of carcinogens. Hence, a convenient and efficient method to monitor ClO- and HSO3- in ecological environments is highly desired. In this article, an "ON-OFF-ON" fluorescent probe based on nitrogen-doped carbon dots (N-CDs) for the detection of ClO- and HSO3- has been demonstrated successfully. Because of the destruction of the surface passivation layer, the fluorescence of the N-CDs was quenched by ClO-. Furthermore, the quenched fluorescence of the N-CDs was restored efficiently through the increase in conjugation from the attached sulfo groups, indicating the feasibility of ClO- and HSO3- detection. This fluorescent probe exhibited excellent sensitivity and selectivity to ClO- and HSO3- detection with the limits of detection (LODs) of 3.4 µM and 0.27 µM in aqueous solution, respectively. In addition, the as-prepared N-CDs were successfully applied to detect both ClO- and HSO3- in living cells due to their low toxicity and fast response speed.


Assuntos
Carbono/química , Corantes Fluorescentes/química , Ácido Hipocloroso/análise , Pontos Quânticos/química , Sulfitos/análise , Técnicas Biossensoriais/métodos , Corantes Fluorescentes/efeitos da radiação , Corantes Fluorescentes/toxicidade , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Luz , Limite de Detecção , Imagem Óptica/métodos , Pontos Quânticos/efeitos da radiação , Pontos Quânticos/toxicidade
13.
Cell Tissue Res ; 363(2): 399-409, 2016 02.
Artigo em Inglês | MEDLINE | ID: mdl-26310139

RESUMO

Epoxyeicosatrienoic acids (EETs), the metabolites of arachidonic acid derived from the cytochrome P450 (CYP450) epoxygenases, are mainly metabolized by soluble epoxide hydrolase (sEH) to their corresponding diols. EETs but not their diols, have anti-inflammatory properties and inhibition of sEH might provide protective effects against inflammatory fibrosis. We test the effects of a selected sEH inhibitor, 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl) urea (TPPU), on bleomycin-induced pulmonary fibrosis (PF) in mice. A mouse model of PF was established by intratracheal injection of bleomycin and TPPU was administered for 21 days after bleomycin injection. We found TPPU treatment improved the body weight loss and survival rate of bleomycin-stimulated mice. Histological examination showed that TPPU treatment alleviated bleomycin-induced inflammation and maintained the alveolar structure of the pulmonary tissues. TPPU also decreased the bleomycin-induced deposition of collagen and the expression of procollagen I mRNA in lung tissues of mice. TPPU decreased the transforming growth factor-ß1 (TGF-ß1), interleukin-1ß (IL-1ß) and IL-6 levels in the serum of bleomycin-stimulated mice. Furthermore, TPPU inhibited the proliferation and collagen synthesis of mouse fibroblasts and partially reversed TGF-ß1-induced α-smooth muscle actin expression. Our results indicate that the inhibition of sEH attenuates bleomycin-induced inflammation and collagen deposition and therefore prevents bleomycin-induced PF in a mouse model.


Assuntos
Epóxido Hidrolases/antagonistas & inibidores , Compostos de Fenilureia/uso terapêutico , Piperidinas/uso terapêutico , Fibrose Pulmonar/tratamento farmacológico , Animais , Bleomicina , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Colágeno/metabolismo , Eicosanoides/sangue , Eicosanoides/química , Epóxido Hidrolases/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Interleucina-1beta/sangue , Interleucina-6/sangue , Pulmão/efeitos dos fármacos , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Compostos de Fenilureia/farmacologia , Piperidinas/farmacologia , Fibrose Pulmonar/sangue , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/patologia , Fase S/efeitos dos fármacos , Solubilidade , Fator de Crescimento Transformador beta1/sangue , Redução de Peso/efeitos dos fármacos
14.
Int J Exp Pathol ; 96(4): 269-75, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25944684

RESUMO

Interleukin (IL)-17A is a pro-inflammatory cytokine that markedly enhances inflammatory responses in the lungs by recruiting neutrophils and interacting with other pro-inflammatory mediators. Reducing the expression of IL-17A could attenuate inflammation in the lungs. However, whether VIP exerts its anti-inflammatory effects by regulating the expression of IL-17A has remained unclear. Here, we show that there is a remarkable increase of IL-17A in bronchoalveolar lavage fluid (BALF) and lung tissue of mice with acute lung injury (ALI). Moreover, lipopolysaccharides (LPS) stimulated elevated expression of IL-17A, which was evident by the enhanced levels of mRNA and protein observed. Furthermore, we also found that VIP inhibited LPS-mediated IL-17A expression in a time- and dose-dependent manner in an in vitro model of ALI and that this process might be mediated via the phosphokinase A (PKA) and phosphokinase C (PKC) pathways. Taken together, our results demonstrated that VIP might be an effective protector during ALI by suppressing IL-17A expression.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Interleucina-17/biossíntese , Macrófagos/metabolismo , Proteína Quinase C/metabolismo , Peptídeo Intestinal Vasoativo/metabolismo , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Animais , Líquido da Lavagem Broncoalveolar/imunologia , Modelos Animais de Doenças , Regulação para Baixo , Ensaio de Imunoadsorção Enzimática , Regulação da Expressão Gênica/fisiologia , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/fisiologia
15.
Talanta ; 271: 125687, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38271843

RESUMO

Ascorbic acid (AA) is an essential vitamin in humans, and numerous AA detection studies have been conducted. Most quantum dots (QDs)-based approaches depend on redox reactions involving AA, and they require the introduction of an intermediate (e.g., metal ions, OPD, TMB) or the assembly of fluorescent substances with nanosheets (such as MnO2) that can be degraded by AA. These methods are complex, unstable, and are susceptible to interferences. To address these problems, a core-shell fluorescence probe was developed for turn-on sensing of AA. The transition metal oxide shell FeOOH was generated around the surface of CuInZnS QDs to quench the fluorescence. In the presence of AA, the FeOOH shell was decomposed into Fe2+ and the fluorescence of QDs was recovered. Using a physical shell, the obtained nanocomposite realized direct AA detection, avoiding the effects of interfering substances caused by QDs exposure. Moreover, our probe showed great potential in point-of-care tests and was readily adapted for use as a smartphone-assisted paper sensor.

16.
Food Chem ; 460(Pt 1): 140525, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39047472

RESUMO

The determination of vitamin B6 (VB6) in food is of great significance due to its vital role in maintaining health and its necessity for ingestion through dietary sources. Therefore, based on ionic liquid-based yellow-emitting carbon dots (Y-CDs), a novel fluorescence-smartphone dual-mode method was first developed. The present method was applied to the detection of VB6 in milk. In the fluorescence method, the formation of complexes between VB6 and Y-CDs results in a significant decrease of the fluorescence intensity of Y-CDs. VB6 in milk samples was successfully determined according to this method, which exhibited a low detection limit (5 × 10-5 mg/mL) and excellent recoveries (98.80%-103.80%), demonstrating its feasibility in real sample analysis. In addition, the smartphone-based analysis method was established by researching the correlation between different VB6 concentrations and the (R + B) values of Y-CDs. When this method was applied, the detection process of VB6 was simplified. By combining the two methods, the possibility of incorrect analysis results can be effectively reduced, and the reliability of detection results can be improved through cross-validation of the two methods. Compared with traditional chromatography and electrochemical methods, the dual-mode method was more rapid, convenient, accurate, and suitable for the detection of VB6.


Assuntos
Carbono , Líquidos Iônicos , Leite , Pontos Quânticos , Smartphone , Vitamina B 6 , Leite/química , Animais , Carbono/química , Pontos Quânticos/química , Líquidos Iônicos/química , Vitamina B 6/análise , Fluorescência , Limite de Detecção , Espectrometria de Fluorescência/métodos , Contaminação de Alimentos/análise , Bovinos
17.
Food Chem ; 463(Pt 2): 141213, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39270494

RESUMO

As an antioxidant and preservative agent, nitrite (NO2-) plays an essential role in the food industry to maintain freshness or inhibit microbial growth. However, excessive addition of NO2- is detrimental to health, so accurate and portable detection of NO2- is critical for food quality control. Notably, the selectivity of most carbon dots (CDs)-based fluorescence sensors was not enough due to the nonspecific interaction mechanism of hydrogen bond, electrostatic interaction and inner filter effect etc. Herein, a novel fluorescence/UV-vis absorption (FL/UV-vis) dual-mode sensor was developed on basis of mC-CDs, which were prepared by simple solvothermal treatment of m-Phenylenediamine (m-PDA) and cyanidin cation (CC). The fluorescence of these mC-CDs could be selectively responded by NO2- through the specific diazo coupling reaction between NO2- and amino groups on the surface of mC-CDs, thus effectively improving the selectivity of NO2- detection. The CDs-based fluorescence sensor possessed a low detection limit of 0.091 µM and 0.143 µM for FL and UV-vis methods and the excellent linear range of 0.0-60.0 µM. Furthermore, the mC-CDs sensor was employed to detect NO2- in real samples with a recovery rate of 97.11 %-104.15 % for quantitative addition. Moreover, the smartphone-assisted fluorescence sensing platform developed could identify the subtle color changes that could not be distinguished by the naked eye, and had the advantages of fast detection speed and intelligence. More importantly, the portable solid phase sensor based on mC-CDs had been successfully applied to the specific fluorescence identification and concentration monitoring of NO2-. Accordingly, the designed sensor provided a new strategy for the highly selective and convenient sensing of NO2- in food substrates, and paved the way for the wide application of CDs-based nanomaterials in the detection of food safety.

18.
J Colloid Interface Sci ; 662: 48-57, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38335739

RESUMO

Presently, most fluorescent probes for amino acid enantiomers detection require metal ions participation, which greatly increases the detection steps and costs, and affects the accuracy of detection results. To solve this problem, a dual pattern recognition sensor of chiral carbon dots (L-Try-Thr-CDs) with a quantum yield of 36.23 % was prepared by a one-step solvothermal method for the highly selective detection of lysine (Lys) enantiomers. Under optimal experimental conditions, the fluorescence and circular dichroism (CD) signals of the obtained L-Try-Thr-CDs could rapidly and effectively responded to L-Lys with limits of detection (LOD) of 16.51 nM and 24.38 nM, respectively, much lower than previously reported sensors. Importantly, the L-Try-Thr-CDs as a dual-mode sensor could not only detect amino acid enantiomers and simplify the steps, but also avoid inaccurate detection results due to unstable metal ions. Furthermore, the L-Try-Thr-CDs could detect L-Lys in living cells via a fluorescence microscope because of their excellent fluorescence characteristics and low toxicity. These results indicated that the dual-mode sensor not only provided a practical strategy for the design of new fluorescent probes, but also possessed outstanding application prospects in the accurate detection of lysine enantiomers.


Assuntos
Pontos Quânticos , Pontos Quânticos/química , Corantes Fluorescentes/química , Triptofano , Lisina , Carbono/química , Treonina , Estereoisomerismo , Íons , Espectrometria de Fluorescência
19.
J Genet Genomics ; 51(4): 407-418, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37709195

RESUMO

During spermiogenesis, haploid spermatids undergo dramatic morphological changes to form slender sperm flagella and cap-like acrosomes, which are required for successful fertilization. Severe deformities in flagella cause a male infertility syndrome, multiple morphological abnormalities of the flagella (MMAF), while acrosomal hypoplasia in some cases leads to sub-optimal embryonic developmental potential. However, evidence regarding the occurrence of acrosomal hypoplasia in MMAF is limited. Here, we report the generation of base-edited mice knocked out for coiled-coil domain-containing 38 (Ccdc38) via inducing a nonsense mutation and find that the males are infertile. The Ccdc38-KO sperm display acrosomal hypoplasia and typical MMAF phenotypes. We find that the acrosomal membrane is loosely anchored to the nucleus and fibrous sheaths are disorganized in Ccdc38-KO sperm. Further analyses reveal that Ccdc38 knockout causes a decreased level of TEKT3, a protein associated with acrosome biogenesis, in testes and an aberrant distribution of TEKT3 in sperm. We finally show that intracytoplasmic sperm injection overcomes Ccdc38-related infertility. Our study thus reveals a previously unknown role for CCDC38 in acrosome biogenesis and provides additional evidence for the occurrence of acrosomal hypoplasia in MMAF.

20.
Front Pediatr ; 12: 1394400, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38873584

RESUMO

Introduction: Limited knowledge exists regarding the impact of paternal smoking and alcohol exposure on the development of allergic rhinitis in offspring. Our study aimed to investigate the potential association between preconception paternal smoking and alcohol exposure and the likelihood of children allergic rhinitis. Methods: A retrospective case-control study of 556 prepubertal children aged 3-12 years was performed. The participants were 278 children with allergic rhinitis and 278 healthy controls matched for age and gender. Self-administered questionnaires were distributed and collected on-site, focusing on various factors related to the children's fathers, mothers, and the children themselves during the first year of life and the past 12 months, from March to October 2022. Results: Multivariate analysis demonstrated that paternal smoking, paternal alcohol consumption prior to conception, paternal allergic diseases, children with a family history of allergies, maternal allergic diseases and pregnancy complications were identified as independent risk factors for allergic rhinitis in their offspring. Moreover, after considering confounding factors, it was observed that paternal smoking exceeding 5 cigarettes per day in the year preceding pregnancy and exceeding 11 years significantly elevated the likelihood of allergic rhinitis in children (OR = 2.009 and 2.479, respectively). Furthermore, the consumption of alcohol by the father at intervals of less than one month in the year prior to pregnancy and a duration of alcohol consumption exceeding 11 years prior to pregnancy are both associated with a significantly increased risk of allergic rhinitis in children (OR = 2.005 and 3.149, respectively). Conclusions: Paternal smoking and alcohol consumption prior to conception contribute to an increased risk of allergic rhinitis in children, with the risk being dependent on the dosage and duration of exposure. Therefore, it is important to not only focus on personal and maternal environmental exposures when considering the occurrence risk of allergic rhinitis in children, but also to consider paternal detrimental exposures prior to conception.

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