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1.
Environ Pollut ; 281: 117015, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33819669

RESUMO

Chlorinated paraffins (CPs), a type of toxic and persistent organic substances, can persist in environmental media for a long time and have adverse effects on human health. Thus, it is of great importance to investigate the accumulation and environmental behavior of CPs in industrial areas. In this study, farmland soil, water, and sediment core samples from abandoned oxidation ponds used by three chemical plants to treat wastewater over the past 38 years were investigated in detail. Results show that the concentration of CPs in sediments varied significantly with the water flow direction. The oxidation pond closest to a sewage outlet had the highest concentrations of short-chain chlorinated paraffin (SCCPs) and medium-chain chlorinated paraffin (MCCPs), within the ranges of 44.0-6.21 × 104 ng/g dw (mean 9.32 × 103 ng/g dw) and 143-1.30 × 106 ng/g dw (mean 1.22 × 105 ng/g dw), respectively. However, in the oxidation pond farthest from the sewage outlet, CP concentrations in sediments were significantly reduced, with ∑SCCPs and ∑MCCPs concentrations ranging from N.D.-249 ng/g dw (mean 66.8 ng/g dw) and N.D.-222 ng/g dw (mean 34.0 ng/g dw), respectively. Moreover, MCCP level in the water was below the detection limit, while the concentration of SCCP ranged from 41.0 to 1.53 × 103 ng/L (mean 267 ng/L). Finally, a remarkable spatial trend and specific congener distribution were observed in the sediment test results. The horizontal and vertical distributions of the sediments indicate that short-chain (C10-11) and low-chlorinated (Cl6-7) homologs are more likely to migrate deeper or farther away from the pollution source.

2.
World J Surg Oncol ; 19(1): 102, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33827589

RESUMO

BACKGROUND: Laparoscopic surgery has been widely accepted to treat early-stage gastric cancer. However, it is still controversial to perform laparoscopic gastrectomy plus D2 lymphadenectomy for locally advanced gastric cancer. We performed the present study to compare the long-term outcomes of patients after laparoscopic or open gastrectomy plus D2 lymphadenectomy. METHODS: The clinicopathological data of 182 gastric cancer patients receiving gastrectomy plus D2 lymphadenectomy between January 2011 and December 2015 at Shenzhen Traditional Chinese Medicine Hospital were retrospectively retrieved. The overall survival (OS) and disease-free survival (DFS) of these 182 patients were compared. Then, the prognostic significance of positive lymph node ratio (LNR) was assessed. RESULTS: As a whole, OS (P = 0.789) and DFS (P = 0.672) of patients receiving laparoscopic gastrectomy plus D2 lymphadenectomy were not significantly different from those of patients receiving open surgery. For stage I patients, laparoscopic gastrectomy plus D2 lymphadenectomy was not significantly different from open surgery in terms of OS (P = 0.573) and DFS (P = 0.157). Similarly, for stage II patients, laparoscopic gastrectomy plus D2 lymphadenectomy was not significantly different from open surgery in terms of OS (P = 0.567) and DFS (P = 0.830). For stage III patients, laparoscopic gastrectomy plus D2 lymphadenectomy was not significantly different from open surgery in terms of OS (P = 0.773) and DFS (P = 0.404). Laparoscopic or open gastrectomy plus D2 lymphadenectomy was not proven by Cox regression analysis to be an independent prognostic factor for OS and DFS. High LNR was significantly associated with worse OS (P < 0.001) and DFS (P < 0.001). Surgical type did not significantly affect prognosis of patients with low LNR or survival of patients with high LNR. CONCLUSIONS: For patients with gastric cancer, laparoscopic gastrectomy plus D2 lymphadenectomy was not inferior to open surgery in terms of long-term outcomes. LNR is a useful prognostic marker for GC patients.

3.
Sci Total Environ ; 777: 146101, 2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33676212

RESUMO

Novel brominated flame retardants (NBFRs) have emerged as an alternative to traditional brominated flame retardants (BFRs); however, they may pose risks to the environment and human health. To investigate the occurrence, temporal trends, and human exposure of seven typical NBFRs (∑7 NBFRs), seven species of mollusks (n = 329) were collected from coastal cities in the Chinese Bohai Sea area from 2011 to 2018. The ∑7 NBFRs ranged from 1.52 to 154 ng/g dry weight (dw) (mean: 14.9 ± 21.21 ng/g dw), higher than in other areas worldwide. Decabromodiphenylethane (DBDPE) was the main contaminant, contributing to 33% of the NBFRs. Temporal trends indicate that the DBDPE and 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) concentrations in mollusks increased significantly (P < 0.05) at rates of about 26% and 5.4%, respectively. This suggests that these NBFRs are continuously released into the environment of the Bohai Sea area. The higher NBFR concentrations in the southern sampling sites relative to the northern sampling sites were consistent with the spatial distribution of the NBFR industry in the Bohai Rim Economic Circle. Chlamys farreri possessed the highest ∑7 NBFR concentrations compared with the other species, while the lowest concentrations were found in Neverita didyma and Rapana venosa, suggesting interspecific differences in bioaccumulation. The estimated daily intake of NBFRs was low, and as the main contaminant, DBDPE was unlikely to pose significant human health risks. Overall, this is the first study to comprehensively assess the occurrence, spatial distribution, and temporal trends of NBFRs in mollusks.

4.
Elife ; 102021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33689680

RESUMO

Animal behavior is regulated based on the values of future rewards. The phasic activity of midbrain dopamine neurons signals these values. Because reward values often change over time, even on a subsecond-by-subsecond basis, appropriate behavioral regulation requires continuous value monitoring. However, the phasic dopamine activity, which is sporadic and has a short duration, likely fails continuous monitoring. Here, we demonstrate a tonic firing mode of dopamine neurons that effectively tracks changing reward values. We recorded dopamine neuron activity in monkeys during a Pavlovian procedure in which the value of a cued reward gradually increased or decreased. Dopamine neurons tonically increased and decreased their activity as the reward value changed. This tonic activity was evoked more strongly by non-burst spikes than burst spikes producing a conventional phasic activity. Our findings suggest that dopamine neurons change their firing mode to effectively signal reward values in a given situation.

5.
J Opt Soc Am A Opt Image Sci Vis ; 38(3): 321-327, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33690460

RESUMO

In dual-wavelength interferometry, the key issue is how to efficiently retrieve the phases at each wavelength using the minimum number of wavelength-multiplexed interferograms. To address this problem, a new dual-wavelength interferogram decoupling method with the help of deep learning is proposed in this study. This method requires only three randomly phase-shifted dual-wavelength interferograms. With a well-trained deep neural network, one can obtain three interferograms with arbitrary phase shifts at each wavelength. Using these interferograms, the wrapped phases of a single wavelength can be extracted, respectively, via an iterative phase retrieval algorithm, and then the phases at different synthetic beat wavelengths can be calculated. The feasibility and applicability of the proposed method are demonstrated by simulation experiments of the spherical cap and red blood cell, respectively. This method will provide a solution for the problem of phase retrieval in multiwavelength interferometry.

6.
Theranostics ; 11(10): 4839-4857, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33754031

RESUMO

Reactive oxygen species (ROS) serve as cell signaling molecules generated in oxidative metabolism and are associated with a number of human diseases. The reprogramming of redox metabolism induces abnormal accumulation of ROS in cancer cells. It has been widely accepted that ROS play opposite roles in tumor growth, metastasis and apoptosis according to their different distributions, concentrations and durations in specific subcellular structures. These double-edged roles in cancer progression include the ROS-dependent malignant transformation and the oxidative stress-induced cell death. In this review, we summarize the notable literatures on ROS generation and scavenging, and discuss the related signal transduction networks and corresponding anticancer therapies. There is no doubt that an improved understanding of the sophisticated mechanism of redox biology is imperative to conquer cancer.

7.
Cell Death Dis ; 12(2): 202, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33608512

RESUMO

Ring1b is a core subunit of polycomb repressive complex 1 (PRC1) and is essential in several high-risk cancers. However, the epigenetic mechanism of Ring1b underlying breast cancer malignancy is poorly understood. In this study, we showed increased expression of Ring1b promoted metastasis by weakening cell-cell adhesions of breast cancer cells. We confirmed that Ring1b could downregulate E-cadherin and contributed to an epigenetic rewiring via PRC1-dependent function by forming distinct complexes with DEAD-box RNA helicases (DDXs) or epithelial-mesenchymal transition transcription factors (EMT TFs) on site-specific loci of E-cadherin promoter. DDXs-Ring1b complexes moderately inhibited E-cadherin, which resulted in an early hybrid EMT state of epithelial cells, and EMT TFs-Ring1b complexes cooperated with DDXs-Ring1b complexes to further repress E-cadherin in mesenchymal-like cancer cells. Clinically, high expression of Ring1b with DDXs or EMT TFs predicted low levels of E-cadherin, metastatic behavior, and poor prognosis. These findings provide an epigenetic regulation mechanism of Ring1b complexes in E-cadherin expression. Ring1b complexes may be potential therapeutic targets and biomarkers for diagnosis and prognosis in invasion breast cancer.

9.
Environ Sci Technol ; 55(7): 4103-4114, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33523638

RESUMO

Intensified efforts to curb transmission of the Severe Acute Respiratory Syndrome Coronavirus-2 might lead to an elevated concentration of disinfectants in domestic wastewater and drinking water in China, possibly resulting in the generation of numerous toxic disinfection byproducts (DBPs). In this study, the occurrence and distribution of five categories of DBPs, including six trihalomethanes (THMs), nine haloacetic acids (HAAs), two haloketones, nine nitrosamines, and nine aromatic halogenated DBPs, in domestic wastewater effluent, tap water, and surface water were investigated. The results showed that the total concentration level of measured DBPs in wastewater effluents (78.3 µg/L) was higher than that in tap water (56.0 µg/L, p = 0.05), followed by surface water (8.0 µg/L, p < 0.01). Moreover, HAAs and THMs were the two most dominant categories of DBPs in wastewater effluents, tap water, and surface water, accounting for >90%, respectively. Out of the regulated DBPs, none of the wastewater effluents and tap water samples exceeded the corresponding maximum guideline values of chloroform (300 µg/L), THM4 (80 µg/L), NDMA (100 ng/L), and only 2 of 35 tap water samples (67.6 and 63.3 µg/L) exceeded the HAA5 (60 µg/L) safe limit. HAAs in wastewater effluents showed higher values of risk quotient for green algae. This study illustrates that the elevated use of disinfectants within the guidance ranges during water disinfection did not result in a significant increase in the concentration of DBPs.


Assuntos
Desinfetantes , Água Potável , Poluentes Químicos da Água , Purificação da Água , China , Desinfetantes/análise , Desinfecção , Água Potável/análise , Humanos , Pandemias , Trialometanos/análise , Águas Residuárias , Água , Poluentes Químicos da Água/análise
10.
Environ Pollut ; 273: 116460, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33485002

RESUMO

Both legacy and emerging per- and polyfluoroalkyl substances (PFAS) have been found to be threats to human health. In particular, fetuses are sensitive to xenobiotics and the placenta functions as a significant barrier for environmental pollutants. The placental transfer of PFAS is closely related to their interactions with proteins. In this study, 54 human placental samples were collected to investigate the occurrence of legacy and emerging PFAS in human placenta, including perfluorinated carboxylates (PFCAs), perfluorinated sulfonates (PFSAs), chlorinated polyfluoroalkyl ether sulfonic acids (Cl-PFESAs), and fluorotelomer sulfonates (FTSAs). Among the legacy PFAS, perfluorooctanesulfonate (PFOS), perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA) were detected in all samples, with PFOS and PFOA being the two predominant (mean: 0.457 and 0.242 ng/g wet weight, respectively). Among the emerging PFAS, 6:2 Cl-PFESA was detected in all samples with the mean value of 0.104 ng/g wet weight, while the detect frequency (DF) of 8:2 Cl-PFESAs was only 24%. The concentration and DF of the four FTSA congeners were low in the placentas. Molecular docking calculation results showed that the binding affinities of PFAS to the human serum albumin (HSA) were increased with chain length in each category except for the PFCAs, of which the perfluoroundecanoic acid (PFUnDA) was the turning point of binding affinity to HSA. For PFSAs, their binding affinities to organic anion transporter 4 (OAT4) were increased with the chain length except for the sodium perfluoro-1-heptanesulfonate (PFHpS) and sodium perfluoro-1-nonanesulfonate (PFNS). The calculation results demonstrated that the placental transfer of PFAS is closely related to chain length. The findings in the study can help better understand the occurrence of the PFAS in the human placenta and the placental transfer mechanisms of PFAS in human beings.

11.
Anal Chem ; 93(4): 1962-1968, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33439629

RESUMO

Nanoscale silver (n-Ag) including silver nanoparticles (Ag-NPs), silver chloride nanoparticles (AgCl-NPs), and silver sulfide nanoparticles (Ag2S-NPs) and their corresponding ionic counterpart, namely, dissolved Ag, may coexist in soils. X-ray absorption near edge spectroscopy (XANES) is used to elucidate the speciation of n-Ag in soils, whereas it possesses drawbacks like high costs, rare availability of the instrument, and providing semiquantitative data. We developed a new method for the identification and speciation of n-Ag in soils and sediments based on a sequential extraction technique coupled with inductively coupled plasma optical emission spectrometry. Extraction conditions were first evaluated, establishing the optimal extraction procedure; Ag-NPs, AgCl-NPs, and dissolved Ag in soil were simultaneously extracted by using an aqueous solution of 10 mM tetrasodium pyrophosphate, followed by selective isolation and quantification via AgCl-NPs dissolution (4.45 M aqueous ammonia), centrifugation (Ag-NPs), and detection. The Ag2S-NPs remaining in the soil were then extracted with Na2S solution at pH 7.0 through selective complexation. Optimal recoveries of Ag-NPs, AgCl-NPs, Ag2S-NPs, and dissolved Ag were 99.1 ± 2.4%, 112.0 ± 3.4%, 96.4 ± 4.0%, and 112.2 ± 4.1%, respectively. The method was validated to investigate the speciation of n-Ag in soils and sediments, exhibiting the distribution of Ag-NPs, AgCl-NPs, Ag2S-NPs, and dissolved Ag in each sample, wherein Ag2S-NPs, the major species of n-Ag, accounted for 35.42-68.87% of the total Ag. The results of n-Ag speciation in soil are comparable to those obtained through the linear combination fitting of XANES. This method thus is a powerful, yet convenient, substitute for XANES to understand the speciation of n-Ag in complex solid matrices.

12.
Asian J Androl ; 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33402547

RESUMO

This study aimed to evaluate the therapeutic effect of IR-61, a novel mitochondrial heptamethine cyanine dye with antioxidant effects, on diabetes mellitus-induced erectile dysfunction (DMED). Eight-week-old male Sprague-Dawley rats were intraperitoneally injected with streptozotocin (STZ) to induce type 1 diabetes. Eight weeks after STZ injection, all rats were divided into three groups: the control group, DM group, and DM + IR-61 group. In the DM + IR-61 group, the rats were administered IR-61 (1.6 mg kg-1) twice a week by intravenous injection. At week 13, erectile function was evaluated by determining the ratio of the maximal intracavernous pressure to mean arterial pressure, and the penises were then harvested for fluorescent imaging, transmission electron microscopy, histological examinations, and Western blot analysis. Whole-body imaging suggested that IR-61 was highly accumulated in the penis after intravenous injection. IR-61 treatment significantly improved the maximal ICP of diabetic rats. Additionally, IR-61 ameliorated diabetes-induced inflammation, apoptosis, and phenotypic transition of corpus cavernosum smooth muscle cells (CCSMCs) in penile tissue. IR-61 also attenuated mitochondrial damage, reduced reactive oxygen species production in the corpus cavernosum and upregulated sirtuin1 (SIRT1), sirtuin3 (SIRT3), nuclear factor (erythroid-derived 2)-like 2 (Nrf2), and heme oxygenase expression in penile tissue. In conclusion, IR-61 represents a potential therapeutic option for DMED by protecting the mitochondria of CCSMCs, which may be mediated by activation of the SIRT1, SIRT3, and Nrf2 pathways.

13.
Nat Commun ; 12(1): 102, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397994

RESUMO

Pro-inflammatory activation of adipose tissue macrophages (ATMs) is causally linked to obesity and obesity-associated disorders. A number of studies have demonstrated the crucial role of mitochondrial metabolism in macrophage activation. However, there is a lack of pharmaceutical agents to target the mitochondrial metabolism of ATMs for the treatment of obesity-related diseases. Here, we characterize a near-infrared fluorophore (IR-61) that preferentially accumulates in the mitochondria of ATMs and has a therapeutic effect on diet-induced obesity as well as obesity-associated insulin resistance and fatty liver. IR-61 inhibits the classical activation of ATMs by increasing mitochondrial complex levels and oxidative phosphorylation via the ROS/Akt/Acly pathway. Taken together, our findings indicate that specific enhancement of ATMs oxidative phosphorylation improves chronic inflammation and obesity-related disorders. IR-61 might be an anti-inflammatory agent useful for the treatment of obesity-related diseases by targeting the mitochondria of ATMs.


Assuntos
Tecido Adiposo/metabolismo , Sistemas de Liberação de Medicamentos , Macrófagos/metabolismo , Mitocôndrias/metabolismo , Obesidade/tratamento farmacológico , Bibliotecas de Moléculas Pequenas/uso terapêutico , Animais , Peso Corporal/efeitos dos fármacos , Fígado Gorduroso/genética , Fígado Gorduroso/patologia , Inflamação/genética , Inflamação/patologia , Resistência à Insulina , Fígado/metabolismo , Fígado/patologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Obesidade/genética , Obesidade/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células RAW 264.7 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Perda de Peso/efeitos dos fármacos
14.
Free Radic Biol Med ; 164: 417-428, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33418112

RESUMO

Radiation-induced pulmonary fibrosis (RIPF) is a common complication during thoracic radiotherapy, but there are few effective treatments. Here, we identify IR-780, a mitochondria-targeted near-infrared (NIR) dye, can selectively accumulate in the irradiated lung tissues. Besides, IR-780 significantly alleviates radiation-induced acute lung injury and fibrosis. Furthermore, our results show that IR-780 prevents the differentiation of fibroblasts and the release of pro-fibrotic factors from alveolar macrophages induced by radiation. Besides, IR-780 downregulates the expression of glycolysis-associated genes, and 2-Deoxy-d-glucose (2-DG) also prevents the development of fibrosis in vitro, suggesting radioprotective effects of IR-780 on RIPF might be related to glycolysis regulation. Finally, IR-780 induces tumour cell apoptosis and enhances radiosensitivity in representative H460 and A549 cell lines. These findings indicate that IR-780 is a potential therapeutic small-molecule dye during thoracic radiotherapy.

15.
J Environ Sci (China) ; 99: 275-280, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33183706

RESUMO

Pristine alpine regions are ideal regions for investigating the long-range atmospheric transport and cold trapping effects of short chain chlorinated paraffins (SCCPs). The concentrations and alpine condensation of SCCPs were investigated in lichen samples collected from the southeastern Tibetan Plateau. The concentrations of SCCPs ranged from 3098 to 6999 ng/g lipid weight (lw) and appeared to have an increasing trend with altitude. For congeners, C10 dominated among all the congener groups. The different environmental behavior for different congener groups was closely related to their octanol-air partition coefficient (Koa). C10 congeners showed an increasing trend with altitude, whereas C13 congeners were negatively correlated with altitude. Volumetric bioconcentration factors (BCF) of SCCPs reached 8.71 in lichens, which were higher than other semivolatile organic compounds (SVOCs) such as organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and hexabromocyclododecane (HBCD). These results suggested that SCCPs were prone to accumulate in the lichen from the air and provided evidence for the role of lichens as a suitable atmospheric indicator in the Tibetan Plateau.


Assuntos
Hidrocarbonetos Clorados , Bifenilos Policlorados , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Parafina/análise , Bifenilos Policlorados/análise , Tibet
16.
Environ Sci Technol ; 55(1): 230-239, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33307673

RESUMO

The presence of anthropogenically emitted chlorinated paraffins (CPs) has been reported in the pristine regions, providing evidence of their long-range transport. This study comprehensively analyzed the short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) in both gas and particle phases at King George Island, West Antarctica (the Chinese Great Wall Station), from 2014 to 2018. The atmospheric levels of CPs ranged between 71.4 and 4230 pg/m3, with an increasing temporal trend during the sampling time. Three different models (J-P model, H-B model, and L-M-Y model) were built to estimate the progress of gas/particle partitioning of CPs at the measurement site. Furthermore, we compared the measured data of the gas/particle partitioning with the data estimated using three different models. We found that the steady-state model (L-M-Y model) was more suitable for investigating the gas/particle partitioning of CPs instead of equilibrium state models (J-P model and H-B model). The result indicated that steady-state approximation rather than the equilibrium state represents the most predominant contribution to the transport of CPs to the Antarctic region. The steady-state further made it conducive to sustaining the levels of CPs for a more extended period in the atmosphere of West Antarctica.


Assuntos
Hidrocarbonetos Clorados , Parafina , Regiões Antárticas , China , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Ilhas , Parafina/análise
17.
Cartilage ; : 1947603520973255, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33215510

RESUMO

OBJECTIVE: Osteoarthritis (OA) is an incurable joint disease characterized by pronounced pain. MicroRNAs constitute epigenetic mechanisms that may affect OA progression by contributing to changes in chondrocyte phenotype. This study investigates for the first time whether there is a link between miRNA-1 (miR-1) and OA pathogenesis, and the molecular mechanisms involved. DESIGN: OA-associated gene expression, including MMP-13, ADAMTS5, and COL2A1 was compared in chondrocytes from non-OA and OA cartilage, and in SW1353 cells over- and underexpressing miR-1. Bioinformatics and luciferase reporter assay were conducted to confirm whether FZD7 was a target of miR-1. The effects of miR-1 on FZD7 expression and downstream Wnt/ß-catenin signalling were investigated. RESULTS: Non-OA and OA chondrocytes differed significantly in the expression of miR-1 and OA-associated genes. MiR-1 over- and underexpression in SW1353 cells, respectively, reduced and enhanced gene expression associated with cartilage catabolism. FZD7, which has an important role in the Wnt/ß-catenin signaling pathway, was shown to be a potential target of miR-1. MiR-1 binding to FZD7 increased the levels of phosphorylated (inactivated) ß-catenin, thereby preventing downstream ß-catenin signaling. CONCLUSIONS: Inhibition of Wnt/ß-catenin signaling by miR-1 in chondrocytes may attenuate the expression of genes that regulate the activity of catabolic enzymes. This finding may be useful for future investigations of molecular targets for OA treatment.

18.
J Agric Food Chem ; 68(49): 14594-14602, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33186497

RESUMO

Organochlorine pesticides (OCPs), chemicals frequently used in agriculture, are a group of highly toxic and persistent organic pollutants. This study assesses the distribution and congener profiles of residual OCPs in 11 types of vegetable oils collected from Chinese markets. All samples were extracted using the modified QuEChERS method prior to analysis by gas chromatography-triple quadrupole mass spectrometry. The sesame oil samples had the highest concentration of OCPs, within the range of 15.30-59.38 ng/g, whereas the peanut oil samples had the lowest OCP concentrations, within the range of 10.83-35.65 ng/g. The possible effect of the processing technology on the pesticide residues in these vegetable oils was also evaluated. It was found that the pressing method leaves more OCPs in vegetable oils than the aqueous extraction and cold-pressing, but the result for leaching was not obvious. In light of the obtained results, it was estimated that the average daily intake of different pesticides is between 0.01 and 2.20 ng/kg bw/day for urban and rural households. Hence, it can be affirmed that, given the amount of the concentration of OCPs detected in the vegetable oils collected from Chinese markets, there are no obvious health risks for urban and rural households by intake.

19.
Waste Manag ; 118: 452-462, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32977305

RESUMO

Relieving from ammonia inhibition and enhancing the utilization of thermodynamically unfavorable propionate are crucial for methane harvest in the high solid anaerobic digestion (HSAD) of ammonia-rich swine manure. In this study, the potential of dosing zero-valent iron (ZVI, 150 um) for enhancing the methanogenesis to resist total ammonia (TAN) over 5.0 g-N·L-1 was investigated via batch experiments under mesophilic condition. The cumulative methane production was enhanced by 22.2% at ≥160 mM ZVI dosage and the HSAD duration was further shortened by 50.6% at ≥320 mM ZVI dosage. The enhanced methanogenesis was mainly resulted from the full utilization of propionate and the accelerated collapse of posterior-biodegradable organics which might be driven by ZVI. Results of microbial community and qPCR (mcrA) showed that ZVI might trigger the blooming of Methanosarcina (from 27.9% to 78.3%) and Syntrophomonas (0.5% to 3.7%) and attribute to their possible direct interspecies electron transfer (DIET) to enhance propionate utilization. Besides, the main methanogenesis might remain in the effective aceticlastic pathway even under free ammonia (FAN) almost 1.0 g-N·L-1 because syntrophic acetate oxidizing bacteria (SAOB) decreased to almost none at 320 mM ZVI dosage. Dosing ZVI could relieve HSAD from TAN inhibition and more dosage was required to resist FAN inhibition.


Assuntos
Amônia , Esterco , Anaerobiose , Animais , Reatores Biológicos , Ferro , Metano , Suínos
20.
Front Pharmacol ; 11: 1038, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32903813

RESUMO

Metformin has effective therapeutic effects in anti-tumor and anti-fibrotic diseases. However, how the antifibrotic effect of metformin in the eye and how it is transferred are still unclear. Here, the eye drop of metformin treatment was studied in Sprague-Dawley (SD) rats of glaucoma filtrating surgery (GFS). Rats were administered randomly bilateral drops: control group (without surgery), GFS group, metformin group or mitomycin C (MMC) group (sponge application intraoperatively, 0.02%). Bleb features and intraocular pressure (IOP) were assessed for postoperative week 4. Metformin effectively inhibited fibrosis and improved the surgical outcomes of GFS. In vitro, we found that the degree of oxidative stress and fibrosis in metformin pretreated-Human Conjunctival Fibroblasts (HConFs) were reduced; the pro-fibrotic response of HConFs were decreased by inducing macrophagic polarity changes. Besides, the inhibition of nuclear factor erythroid 2-related factor 2 (Nrf2)/AMP-activated protein kinase (AMPK) and the competition of organic cation transporters (OCTs) effectively reduced the anti-fibrotic capability of metformin. Together, this experiment indicates that metformin enters into HConFs cell with OCTs, which can protect against filtrating blebs scar formation in SD rats of GFS via activating AMPK/Nrf2 axis and the downregulation of profibrogenic and inflammatory biomarkers.

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