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1.
Opt Express ; 30(18): 32010-32018, 2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36242271

RESUMO

The parameter-tuning stochastic resonance (SR) method can convert part of the noise energy into the signal energy to suppress the noise and amplify the signal, comparing with traditional weak periodic signal detection methods (e.g., time average method, filtering method, and correlation analysis method). In this work, the numerical calculation is conducted to find the optimal resonance parameters for applying the SR method to the wavelength modulation spectroscopy (WMS). Under the stochastic resonance state, the peak value of 2f signal (a constant concentration of CH4∼20 ppm) is effectively amplified to ∼0.0863 V, which is 3.8 times as much as the peak value of 4000-time average signal (∼0.0231 V). Although the standard deviation also increases from ∼0.0015 V(1σ) to ∼0.003 V(1σ), the SNR can be improved by 1.83 times (from ∼25.9 to ∼15.8) correspondingly. A linear spectral response of SR 2f signal peak value to raw 2f signal peak value is obtained. It suggests that the SR method is effective for enhancing photoelectric signal under strong noise background.

2.
J Cell Physiol ; 234(9): 15429-15437, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30809808

RESUMO

Fatty acid binding protein 4 (FABP4) is a novel tumor regulator that is abnormally expressed in many human cancers. In our study, upregulated microRNA-211 (miR-211) and reduced FABP4 expression were detected in colorectal cancer (CRC) patients and CRC cells. Mimic miR-211 or anti-miR-211 were transfected to investigate the effects of miR-211 on SW480 cells. The results showed that miR-211 promoted but anti-miR-211 inhibited cell migration, invasion, and epithelial-mesenchymal transition (EMT) of SW480 cells. Luciferase activity was decreased after cotransfection with miR-211 and WT-FABP4-UTR in SW480 cells. And reduced FABP4 protein expression by miR-211 indicated that FABP4 was the targeted gene of miR-211. miR-211 inhibited the activation of peroxisome proliferator-activated receptor (PPAR) γ, whereas overexpression of FABP4 reversed that effect. Finally, FABP4 inhibited the migration, invasion, and EMT of SW480 cells, whereas PPARγ agonist reversed the effects of FABP4. Thus, the miR-211/FABP4/PPARγ axis may be a novel target for CRC therapy.

3.
Chemosphere ; 349: 140773, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38000554

RESUMO

Although the herbicide linuron is banned for use in the EU due to its reproductive and developmental toxicity, it can still be found in randomly sampled foods grown in and outside the EU. It is not clear if metabolites of linuron can contribute to the endocrine disrupting effects following exposure to the parent compound. To address this gap, we analysed linuron and the metabolites 1-(3,4-dichlorophenyl) urea (DCU), 3,4-dichloroaniline (DCA) and 1-(3,4-dichlorophenyl)-3-methoxyurea (DCXU) for androgen receptor (AR) activities and effects on steroidogenesis. Generally, linuron and the metabolites showed qualitatively similar antiandrogenic profiles, but potencies varied. All compounds were AR antagonists, with linuron showing highest potency (IC50 of 2.8 µM). The overall picture of effects on steroidogenesis showed that linuron and metabolites increased the levels of estrogens and corticosteroids, whereas the synthesis of androgens was inhibited. The metabolite DCU was by far the most potent inhibitor of testosterone synthesis (IC50 of 6.7 µM compared to IC50 of 51.1 µM for linuron). We suggest that it is likely that the metabolites contribute to the antiandrogenic effects of linuron in vivo, especially by inhibiting testosterone synthesis.


Assuntos
Herbicidas , Linurona , Linurona/toxicidade , Herbicidas/toxicidade , Androgênios , Antagonistas de Androgênios/toxicidade , Testosterona
4.
Environ Int ; 173: 107815, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36822008

RESUMO

BACKGROUND: Scientific evidence for underestimated toxicity from unintentional exposure to chemical mixtures is mounting. Yet, harmonized approaches on how to assess the actual risk of mixtures is lacking. As part of the European Joint programme 'Human Biomonitoring for Europe' we explored a novel methodology for mixture risk assessment of chemicals affecting male reproductive function. METHODOLOGY: We explored a methodology for chemical mixture risk assessment based on human in vitro data combined with human exposure data, thereby circumventing the drawbacks of using hazard data from rodents and estimated exposure intake levels. Human androgen receptor (hAR) antagonism was selected as the most important molecular initiating event linked to adverse outcomes on male reproductive health. RESULTS: Our work identified 231 chemicals able to interfere with hAR activity. Among these were 61 finally identified as having both reliable hAR antagonist and human biomonitoring data. Calculation of risk quotients indicated that PCBs (118, 138, 157), phthalates (BBP, DBP, DIBP), benzophenone-3, PFOS, methylparaben, triclosan, some pesticides (i.e cypermethrin, ß-endosulfan, methylparathion, p,p-DDE), and a PAH metabolite (1-hydroxypyrene) contributed to the mixture effect. The major chemical mixture drivers were PCB 118, BBP, PFOS, DBP, and the UV filter benzophenone-3, together contributing with 75% of the total mixture effect that was primarily driven by high exposure values. CONCLUSIONS: This viable way forward for mixture risk assessment of chemicals has the advantages of (1) being a more comprehensive mixture risk assessment also covering data-poor chemicals, and (2) including human data only. However, the approach is subjected to uncertainties in terms of in vitro to in vivo extrapolation, it is not ready for decision making, and needs further development. Still, the results indicate a concern for adverse effects on reproductive function in highly exposed boys, especially when considering additional exposure to data-poor chemicals and chemicals acting by other mechanisms of action.


Assuntos
Monitoramento Biológico , Praguicidas , Humanos , Masculino , Benzofenonas , Antagonistas de Receptores de Andrógenos , Praguicidas/toxicidade , Medição de Risco
5.
Infect Drug Resist ; 15: 1921-1931, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35469306

RESUMO

Purpose: Significant antibiotic overuse due to prolonged antibiotic duration has not draw enough attention in developing countries with high antibiotic consumption. We aimed to describe the current status of prolonged early antibiotic duration in very-low-birth-weight (VLBW) infants in a large regional multicenter cohort in China. Patients and Methods: Institution-based prospective cohort study was conducted in all VLBW infants admitted to 16 Grade A tertiary hospitals between January 1, 2019 and December 31, 2020. Early antibiotic use was defined as antibiotic initiation within the first 3 days of life. Prolonged early antibiotic course was defined as early antibiotic initiation for more than 7 days in infants with early-onset sepsis (EOS) or more than 3 days in infants with unlikely EOS. Antibiotic use was described as days of therapy (DOT) per 1000 patient days (PD). Results: Among 1684 eligible VLBW infants, 1544 (91.7%) infants were prescribed with prolonged early antibiotic course, including 618 infants with EOS and 926 infants with unlikely EOS. The median duration of early antibiotic course was 13 (IQR 8;20) days, with 78.0% of courses >7 days and 43.6% of courses >14 days. Total early antibiotic use was 408.3DOT/1000Pd, of which prolonged antibiotic courses accounted for 98.2% of all antibiotic use days. More than three antibiotics used, escalation antibiotic therapy, antibiotics for special use and the use of third generation cephalosporins and carbapenems were significantly common in prolonged courses compared to short courses in both infants with EOS and unlikely EOS group (P<0.05). Conclusion: A large proportion of VLBW infants had excessively prolonged early antibiotic durations in the regional multicenter in China. Timely discontinuation of antibiotics in VLBW infants according to standardized guidelines and limit on the use of third-generation cephalosporins and carbapenems may be key drivers in reducing the antibiotic overuse in developing countries like ours.

6.
Artigo em Inglês | MEDLINE | ID: mdl-36293571

RESUMO

Humans are involuntarily exposed to hundreds of chemicals that either contaminate our environment and food or are added intentionally to our daily products. These complex mixtures of chemicals may pose a risk to human health. One of the goals of the European Union's Green Deal and zero-pollution ambition for a toxic-free environment is to tackle the existent gaps in chemical mixture risk assessment by providing scientific grounds that support the implementation of adequate regulatory measures within the EU. We suggest dealing with this challenge by: (1) characterising 'real-life' chemical mixtures and determining to what extent they are transferred from the environment to humans via food and water, and from the mother to the foetus; (2) establishing a high-throughput whole-mixture-based in vitro strategy for screening of real-life complex mixtures of organic chemicals extracted from humans using integrated chemical profiling (suspect screening) together with effect-directed analysis; (3) evaluating which human blood levels of chemical mixtures might be of concern for children's development; and (4) developing a web-based, ready-to-use interface that integrates hazard and exposure data to enable component-based mixture risk estimation. These concepts form the basis of the Green Deal project PANORAMIX, whose ultimate goal is to progress mixture risk assessment of chemicals.


Assuntos
Misturas Complexas , Poluição Ambiental , Compostos Orgânicos , Humanos , Misturas Complexas/toxicidade , Poluição Ambiental/efeitos adversos , Compostos Orgânicos/toxicidade , Medição de Risco/métodos , União Europeia
7.
Infect Dis Ther ; 11(5): 1935-1947, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35999433

RESUMO

INTRODUCTION: Early onset sepsis (EOS) remains a potentially fatal newborn condition, especially in very preterm infants. Data on the pathogen distribution and antibiotic susceptibility patterns of EOS among very preterm infants are scarce but essential for the choice of empirical antibiotic administration. We sought to assess the epidemiologic characteristics and antibiotic susceptibility patterns of pathogens causing EOS among a cohort of very preterm infants in China. METHODS: This prospective, observational study included a cohort of infants born at a gestational age (GA) less than 32 weeks of 32 newborn intensive care units (NICUs) in China between January 1, 2018 and December 31, 2020. EOS was defined by isolation of pathogenic species from blood culture within 72 h of birth. RESULTS: A total of 108 EOS cases (18.4 per 1000 admissions) were identified among 5865 very preterm infants. Incidence of EOS increased with the decrease of GA and birthweight. Escherichia coli (n = 44, 40.7%) was the most common pathogen, followed by Klebsiella spp. (n = 10, 9.3%). The distribution and proportion of pathogenic bacteria varied significantly by GA. E. coli and Klebsiella spp. showed high resistance to ampicillin and third-generation cephalosporins, while they showed good susceptibility to carbapenem antibiotics and piperacillin-tazobactam. CONCLUSION: Our data demonstrated that pathogens causing neonatal EOS showed high rates of resistance to ampicillin and third-generation cephalosporins. This raised questions about the best empirical antibiotic choice for preterm infants suspected of having EOS in low- and middle-income countries (LMICs).

8.
Toxicol Lett ; 322: 20-31, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31923465

RESUMO

Particulate matter (PM) from combustion processes has been associated with oxidative stress to DNA, whereas effects related to telomere dysfunction are less investigated. We collected air-borne PM from a passenger cabin of a diesel-propelled train and at a training facility for smoke diving exercises. Effects on oxidative stress biomarkers, genotoxicity measured by the comet assay and telomere length in PM-exposed A549 cells were compared with the genotoxicity and telomere length in peripheral blood mononuclear cells (PBMCs) from human volunteers exposed to the same aerosol source. Although elevated levels of DNA strand breaks and oxidatively damaged DNA in terms of Fpg-sensitive sites were observed in PBMCs from exposed humans, the PM collected at same locations did not cause genotoxicity in the comet assay in A549 cells. Nevertheless, A549 cells displayed telomere length shortening after four weeks exposure to PM. This is in line with slightly shorter telomere length in PBMCs from exposed humans, although it was not statistically significant. In conclusion, the results indicate that genotoxic potency measured by the comet assay of PM in A549 cells may not predict genotoxicity in exposed humans, whereas telomere length measurements may be a novel indicator of genotoxic stress in cell cultures and humans.


Assuntos
Dano ao DNA , Exposição por Inalação/efeitos adversos , Material Particulado/toxicidade , Fumaça/efeitos adversos , Homeostase do Telômero/efeitos dos fármacos , Emissões de Veículos/toxicidade , Células A549 , Poluentes Ocupacionais do Ar/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Bombeiros , Humanos , Exposição por Inalação/análise , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/patologia , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Tamanho da Partícula , Homeostase do Telômero/genética
9.
Artigo em Inglês | MEDLINE | ID: mdl-28910712

RESUMO

Cobalt blue is a famous pigment in human history. In the past decade it is widely reported that the cobalt aluminate has been detected in ancient ceramics as blue colorant in glaze, yet the acquired Raman spectra are incredibly different from that of synthesised references, necessitating a reassessment of such contradictory scenario with more accurate analytic strategies. In this study, micro-Raman spectroscopy (MRS) and scanning electron microscopy (SEM) in association with energy dispersive spectrometry (EDS) were performed on under-glaze cobalt pigments from one submerged blue and white porcelain shard dated from Wanli reign (1573-1620CE) of Ming dynasty (1365-1644CE) excavated at Nan'ao I shipwreck off the southern coast of China. The micro-structural inspection reveals that the pigment particles have characteristics of small account, tiny size, heterogeneously distribution, and more importantly, been completely enwrapped by well-developed anorthite crystals in the glaze, indicating that the signals recorded in previous publications are probably not from cobalt pigments themselves but from outside thickset anorthite shell. The further spectromicroscopic analyses confirm this presumption when the accurate spectra of cobalt aluminate pigment and surrounding anorthite were obtained separately with precise optical positioning. Accordingly, we reassess and clarify the previous Raman studies dedicated to cobalt blue pigment in ancient ceramics, e.g. cobalt blue in celadon glaze, and in turn demonstrate the superiority and necessity of coupling spectroscopic analysis with corresponding structure observation, especially in the characterization of pigments from complicated physico-chemical environment like antiquities. Thus, this study promotes a better understanding of Raman spectroscopy study of cobalt blue pigments in art and archaeology field.

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