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1.
Food Chem ; 338: 127980, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32927201

RESUMO

Quercetin has various biological activities, but its poor water solubility and stability limit its applications. In this study, ß-cyclodextrin was used as the host and quercetin was encapsulated in its cavity to prepare an inclusion compound. Then, a nanofilm was formed using electrospinning. Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric differential scanning calorimetry (TG-DSC) were used to characterize the properties of the inclusion compound nanofilms. SEM images showed that the nanofilm prepared by optimizing the electrospinning process parameters had a good nanofiber structure. XRD, FTIR and TG/DSC characterization of the nanofilm showed that quercetin was encapsulated in the cavity of ß-cyclodextrin and was present in the nanofilm. The quercetin was slowly released from the nanofilm and still had good bacteriostatic effects on Staphylococcus aureus and Escherichia coli, indicating that the process of embedding and electrospinning did not affect the antibacterial activity of quercetin.

2.
Adv Radiat Oncol ; 5(5): 943-950, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33083657

RESUMO

Purpose: The dosimetric parameters used clinically to reduce the likelihood of radiation pneumonitis (RP) for lung cancer radiation therapy have traditionally been V20Gy ≤ 30% to 35% and mean lung dose ≤ 20 to 23 Gy; however, these parameters are derived based on studies from photon therapy. The purpose of this study is to evaluate whether such dosimetric predictors for RP are applicable for locally advanced non-small cell lung cancer (LA-NSCLC) patients treated with proton therapy. Methods and Materials: In the study, 160 (78 photon, 82 proton) patients with LA-NSCLC treated with chemoradiotherapy between 2011 and 2016 were retrospectively identified. Forty (20 photon, 20 proton) patients exhibited grade ≥2 RP after therapy. Dose volume histograms for the uninvolved lung were extracted for each patient. The percent lung volumes receiving above various dose levels were obtained in addition to V20Gy and Dmean. These dosimetric parameters and patient characteristics were evaluated with univariate and multivariate logistic regression tests. Receiver operating characteristic curves were generated to obtain the optimal dosimetric constraints through analyzing RP and non-RP sensitivity and specificity values. Results: The multivariate analysis showed V40Gy and Dmean to be statistically significant for proton and photon patients, respectively. V35Gy to V50Gy were strongly correlated to V40Gy for proton patients. Based on the receiver operating characteristic curves, V35Gy to V50Gy had the highest area under the curve compared with other dose levels for proton patients. A potential dosimetric constraint for RP predictor in proton patients is V40Gy ≤ 23%. Conclusions: In addition to V20Gy and Dmean, the lung volume receiving higher doses, such as V40Gy, may be used as an additional indicator for RP in LA-NSCLC patients treated with proton therapy.

3.
Cell Metab ; 2020 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-33027637

RESUMO

Adipocytes control bone mass, but the mechanism is unclear. To explore the effect of postnatal adipocyte elimination on bone cells, we mated mice expressing an inducible primate diphtheria toxin receptor (DTR) to those bearing adiponectin (ADQ)-Cre. DTR activation eliminates peripheral and marrow adipocytes in these DTRADQ mice. Within 4 days of DTR activation, the systemic bone mass of DTRADQ mice began to increase due to stimulated osteogenesis, with a 1,000% expansion by 10-14 days post-DTR treatment. This adipocyte ablation-mediated enhancement of skeletal mass reflected bone morphogenetic protein (BMP) receptor activation following the elimination of its inhibitors, associated with simultaneous epidermal growth factor (EGF) receptor signaling. DTRADQ-induced osteosclerosis is not due to ablation of peripheral adipocytes but likely reflects the elimination of marrow ADQ-expressing cells. Thus, anabolic drugs targeting BMP receptor inhibitors with short-term EGF receptor activation may be a means of profoundly increasing skeletal mass to prevent or reverse pathological bone loss.

4.
J Biol Chem ; 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33051209

RESUMO

Recent studies have suggested that innate immune responses exhibit characteristics associated with memory linked to modulations in both vertebrates and invertebrates. However, the diverse evolutionary paths taken, particularly within the invertebrate taxa, as should lead to similarly diverse innate immunity memory processes. Our understanding of innate immune memory in invertebrates primarily comes from studies of the fruit fly Drosophila melanogaster, the generality of which is unclear. Caenorhabditis elegans typically inhabits soil harboring a variety of fatal microbial pathogens; for this invertebrate, the innate immune system and aversive behavior are the major defensive strategies against microbial infection. However, their characteristics of immunological memory remains infantile. Here we discovered an immunological memory that promoted avoidance and suppressed innate immunity during reinfection with bacteria, which we revealed to be specific to the previously-exposed pathogens. During this trade-off switch of avoidance and innate immunity, the chemosensory neurons AWB and ADF modulated production of serotonin and dopamine, which in turn decreased expression of the innate immunity-associated genes and led to enhanced avoidance via the downstream insulin-like pathway. So our current study profiles the immune memories during C. elegans reinfected by pathogenic bacteria, and further reveal the chemosensory neurons, neurotransmitter(s), and their associated molecular signaling pathways are responsible for a trade-off switch between the two immunological memories.

5.
Environ Sci Technol ; 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33078945

RESUMO

Microplastics (MPs) are ubiquitous in the environment and pose substantial threats to the water ecosystem. However, the impact of natural aging of MPs on their toxicity has rarely been considered. This study found that visible light irradiation with hydrogen peroxide at environmentally relevant concentration for 90 days significantly altered the physicochemical properties and mitigated the toxicity of polyamide (PA) fragments to infantile zebrafish. The size of PA particles was reduced from ∼8.13 to ∼6.37 µm, and nanoparticles were produced with a maximum yield of 5.03%. The end amino groups were volatilized, and abundant oxygen-containing groups (e.g., hydroxyl and carboxyl) and carbon-centered free radicals were generated, improving the hydrophilicity and colloidal stability of degraded MPs. Compared with pristine PA, the depuration of degraded MPs mediated by multixenobiotics resistance was much quicker, leading to markedly lower bioaccumulation in fish and weaker inhibition on musculoskeletal development. By integrating transcriptomics and transgenic zebrafish [Tg(lyz:EGFP)] tests, differences in macrophages-triggered proinflammatory effects, apoptosis via IL-17 signaling pathway, and antioxidant damages were identified as the underlying mechanisms for the attenuated toxicity of degraded MPs. This work highlights the importance of natural degradation on the toxicity of MPs, which has great implications for risk assessment of MPs.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33037880

RESUMO

Manure, soil, and vegetable samples were collected from different-sized livestock farms in Xinxiang, China. The residues of sulfadiazine, sulfamonomethoxine, and sulfamethoxazole were analyzed by high-performance liquid chromatography. The results indicated that the concentration ranges of the three total sulfonamides in manure, soil, and vegetables were 10.13-566.23 µg kg-1, 7.60-176.26 µg kg-1, and 0-32.70 µg kg-1, respectively. The mean concentrations were 219.71 µg kg-1, 70.73 µg kg-1, and 7.08 µg kg-1 for manure, soil, and vegetables, respectively. The mean concentrations in soil were lower than the ecotoxic effect trigger value (100 µg kg-1), indicating a low risk for organisms in soil. The concentrations of the three sulfonamides varied significantly in different types of vegetables and all were lower than the acceptable daily intake value (50 µg (kg day)-1). However, the potential ecotoxicity and danger to human and animal health via accumulation of the antibiotic in the food chain cannot be ignored.

7.
Nucleic Acids Res ; 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33104788

RESUMO

A wealth of single-cell imaging studies have contributed novel insights into chromatin organization and gene regulation. However, a comprehensive understanding of spatiotemporal gene regulation requires developing tools to combine multiple monitoring systems in a single study. Here, we report a versatile tag, termed TriTag, which integrates the functional capabilities of CRISPR-Tag (DNA labeling), MS2 aptamer (RNA imaging) and fluorescent protein (protein tracking). Using this tag, we correlate changes in chromatin dynamics with the progression of endogenous gene expression, by recording both transcriptional bursting and protein production. This strategy allows precise measurements of gene expression at single-allele resolution across the cell cycle or in response to stress. TriTag enables capturing an integrated picture of gene expression, thus providing a powerful tool to study transcriptional heterogeneity and regulation.

8.
Genome ; 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33105087

RESUMO

Clostridium butyricum is an anaerobic bacterium that inhabits broad niches. Clostridium butyricum is known for its production of butyrate, 1,3-propanediol, and hydrogen. This study aimed to present a comparative pan-genome analysis of 24 strains isolated from different niches. We sequenced and annotated the genome of C. butyricum 3-3 isolated from the Chinese baijiu ecosystem. The pan-genome of C. butyricum was open. The core genome, accessory genome, and strain-specific genes comprised 1,011, 4,543, and 1,473 genes, respectively. In the core genome, carbohydrate metabolism was the largest category, and genes in the biosynthetic pathway of butyrate and glycerol metabolism were conserved (in the core or soft-core genome). Furthermore, the 1,3-propanediol operon existed in 20 strains. In the accessory genome, numerous mobile genetic elements belonging to the replication, recombination, and repair (L) category were identified. In addition, genome islands were identified in all 24 strains, ranging from 2 (strain KNU-L09) to 53 (strain SU1), and phage sequences were found in 17 of the 24 strains. This study provides an important genomic framework that could pave the way for the exploration of C. butyricum and future studies on the genetic diversification of C. butyricum.

9.
AIDS Rev ; 23(3)2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33105470

RESUMO

HIV-1 infection poses a major threat to the public health worldwide. The antiretroviral agents that are currently used to treat HIV-1 infection target viral reverse transcriptase, integrase and protease, or block the fusion of viral envelop and cell membrane. Studies have shown that the HIV-1 encoded protein Nef plays an important role in the pathogenesis of viral infection. Nef ensures efficient counterattack against host immune responses as well as long-term evasion of immune surveillance. In addition, Nef, expressing at a high level early in the viral life cycle, is required for maintaining a high viral load in the persistent infection in vivo and for full pathologic potential. Therefore, Nef may be an excellent target to treat HIV-1 infection. In this manuscript, we reviewed five potential Nef inhibitors, namely, DLC27-14, t ightly bound hydroxypyrazole HIV-1 Nef inhibitor B9, 2c-like inhibitors, N-(3-aminoquinoxalin-2-yl)-4-chlorobenzenesulfonamide and compound 1[(7-oxo-7H-benzo[anthracene]-3-yl)amino]anthraquinone, and their working mechanisms. These drugs may be further developed into new regimens for the treatment of HIV-1 infection.

10.
Carbohydr Polym ; 248: 116789, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32919531

RESUMO

This study investigated the particle disintegration of cooked milled rice during in vitro digestion to identify its potential for rapidly predicting glycaemic index (GI). Milled grains and flour of rice with varying GI were cooked, stirred and subjected to digestion followed by kinetics analyses. Despite variations in physicochemical parameters (typically amylose content), flours showed a single-phase-digestion rate (k, ∼0.12 min-1) which did not vary significantly between varieties. In contrast, intact grains were disintegrated into small/intermediate (d < 30 µm, 30 < d < 300 µm) and large (d > 300 µm) particles. The small/intermediate particles comprising 50-70 % starch were initially-digested (0-20 min) at a fast k-f (∼0.05-0.10 min-1), which enabled to differentiate rice digestibility; whereas the large was latter-digested (20-180 min) at a slow k-s (∼0.04 min-1). The sum-ratio of disintegrated-particle 0-300 µm (Q-300) correlated positively with clinical GI values, allowing for a digestibility prediction of intact milled rice grain.

11.
N Engl J Med ; 383(14): 1328-1339, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32997907

RESUMO

BACKGROUND: The efficacy and safety of the anti-programmed death ligand 1 (PD-L1) monoclonal antibody atezolizumab, as compared with those of platinum-based chemotherapy, as first-line treatment for patients with metastatic non-small-cell lung cancer (NSCLC) with PD-L1 expression are not known. METHODS: We conducted a randomized, open-label, phase 3 trial involving patients with metastatic nonsquamous or squamous NSCLC who had not previously received chemotherapy and who had PD-L1 expression on at least 1% of tumor cells or at least 1% of tumor-infiltrating immune cells as assessed by the SP142 immunohistochemical assay. Patients were assigned in a 1:1 ratio to receive atezolizumab or chemotherapy. Overall survival (primary end point) was tested hierarchically according to PD-L1 expression status among patients in the intention-to-treat population whose tumors were wild-type with respect to EGFR mutations or ALK translocations. Within the population with EGFR and ALK wild-type tumors, overall survival and progression-free survival were also prospectively assessed in subgroups defined according to findings on two PD-L1 assays as well as by blood-based tumor mutational burden. RESULTS: Overall, 572 patients were enrolled. In the subgroup of patients with EGFR and ALK wild-type tumors who had the highest expression of PD-L1 (205 patients), the median overall survival was longer by 7.1 months in the atezolizumab group than in the chemotherapy group (20.2 months vs. 13.1 months; hazard ratio for death, 0.59; P = 0.01). Among all the patients who could be evaluated for safety, adverse events occurred in 90.2% of the patients in the atezolizumab group and in 94.7% of those in the chemotherapy group; grade 3 or 4 adverse events occurred in 30.1% and 52.5% of the patients in the respective groups. Overall and progression-free survival favored atezolizumab in the subgroups with a high blood-based tumor mutational burden. CONCLUSIONS: Atezolizumab treatment resulted in significantly longer overall survival than platinum-based chemotherapy among patients with NSCLC with high PD-L1 expression, regardless of histologic type. (Funded by F. Hoffmann-La Roche/Genentech; IMpower110 ClinicalTrials.gov number, NCT02409342.).


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos/uso terapêutico , Antígeno B7-H1/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/efeitos adversos , Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma de Células Escamosas/tratamento farmacológico , Cisplatino/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Mutação , Análise de Sobrevida
12.
JCI Insight ; 5(17)2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32879136

RESUMO

Obesity predisposes to cancer and a virtual universality of nonalcoholic fatty liver disease (NAFLD). However, the impact of hepatic steatosis on liver metastasis is enigmatic. We find that while control mice were relatively resistant to hepatic metastasis, those which were lipodystrophic or obese, with NAFLD, had a dramatic increase in breast cancer and melanoma liver metastases. NAFLD promotes liver metastasis by reciprocal activation initiated by tumor-induced triglyceride lipolysis in juxtaposed hepatocytes. The lipolytic products are transferred to cancer cells via fatty acid transporter protein 1, where they are metabolized by mitochondrial oxidation to promote tumor growth. The histology of human liver metastasis indicated the same occurs in humans. Furthermore, comparison of isolates of normal and fatty liver established that steatotic lipids had enhanced tumor-stimulating capacity. Normalization of glucose metabolism by metformin did not reduce steatosis-induced metastasis, establishing the process is not mediated by the metabolic syndrome. Alternatively, eradication of NAFLD in lipodystrophic mice by adipose tissue transplantation reduced breast cancer metastasis to that of control mice, indicating the steatosis-induced predisposition is reversible.

13.
J Ethnopharmacol ; 266: 113405, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32979412

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Penyanling is made up of Smilacis Glabrae Rhizoma (SG, from Smilar glabra Roxb.), Angelicae Sinensis Radix (AS, from Angelica sinensis (Oliv.) Diels), Salviae Miltiorrhizae Radix et Rhizoma (SM, from Salvia miltiorrhiza Bunge), Sargentodoxae Caulis (SC, from Sargentodoxa cuneata (Oliv.) Rehd.et Wils.), Linderae Radix (LR, from Lindera aggregata (Sims) Kosterm.), Paeoniae Radix Rubra (PR, from Paeonia lactiflora Pall.), Sparganii Rhizoma (SR, from Sparganium stoloniferum (Graebn.) Buch.-Ham.), Corydalis Rhizoma (CoR, from Corydalis yanhusuo W. T. Wang), Cyperi Rhizoma (CyR, from Cyperus rotundus Linn.), Glycyrrhizae Radix et Rhizoma (GR, from Glycyrrhiza uralensis Fisch.), and Patrinia Scabiosaefolia (PS, from Patrinia scabiosaefolia Fisch. ex Trev.) recorded in Chinese Pharmacopoeia. It has been used on pelvic inflammatory disease (PID) for more than twenty years. AIM OF THE STUDY: This study was carried out to illustrate its pharmacological action and clarify its substantial composition. MATERIALS AND METHODS: The anti-inflammatory effects of Penyanling were studied on a PID rat model and a lipopolysaccharides (LPS)-stimulated THP-1 cell line. Histological changes and levels of inflammatory factors in the uterine tube of the PID rat were examined. Levels of nuclear factor-kappa B (NF-κB) in the nuclear of THP-1 cells and NF-κB, IκB-α, and FPR2 in the cytoplasm were tested by Western blot analysis. Substances within Penyanling were scanned with liquid chromatography-quadrupole-time of flight-mass spectrometry (LC-Q-TOF-MS). The contents of total flavonoids, phenolics, and saponins were quantified. RESULTS: The anti-inflammatory effects of Penyanling were observed on PID rats, such as suppressing the infiltrations of lymphocytes and neutrophils in the uterine tube, decreasing the release of interleukin (IL)-1ß, IL-6, IL-8, and monocyte chemotactic protein (MCP)-1, and promoting the production of lipoxin A4 (LXA4). On the other hand, Penyanling regulated the activity of NF-κB signal pathway on the LPS-stimulated THP-1 cell line, which suggested the potential mechanism of its anti-inflammatory effect. Besides, it could promote the expression of formyl peptide receptor 2 (FPR2), which suggested its effect on enhancing the resolution of inflammation. Seventy-six substances were identified by their accurate molecular weights, mass fragment patterns, retention times, and standards if available. Most of these substances were flavonoids, phenolics, saponins, and alkaloids. The contents of total flavonoids, phenolics, and saponins within Penyanling were 0.186, 1.371, and 4.321 mg/mL, respectively. CONCLUSION: Penyanling showed an anti-inflammatory effect on PID, and its potential mechanism involved suppressing NF-κB signal pathway and promoting the resolution of inflammation. The main substances within it were flavonoids, phenolics, saponins, and alkaloids.

14.
Technol Cancer Res Treat ; 19: 1533033820940425, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32912113

RESUMO

BACKGROUND: MiR-887 has been proved to promote the tumorigenesis in diverse cancers, but its function and downstream mechanism in hepatocellular carcinoma remain obscure. METHODS: Quantitative real-time polymerase chain reaction was performed to detect the expression levels of miR-887 in hepatocellular carcinoma tissues and cell lines. MiR-887 mimics and miR-887 inhibitor were transfected into Huh7 and MHCC97H to establish miR-887 overexpression or inhibition models. Cell Counting Kit-8 and colony formation experiment were conducted to monitor cell proliferation. Subcutaneous xenotransplanted tumor model and tail vein injection model in mice were also established to further verify the effect of miR-887 on hepatocellular carcinoma in vivo. The targeting relationship between miR-887 and von Hippel-Lindau tumor suppressor (VHL) was determined by quantitative real-time polymerase chain reaction, Western blot, and luciferase reporter gene assay. RESULTS: miR-887 expression in hepatocellular carcinoma tissues was significantly upregulated. Compared with the control cells, the proliferation and metastasis of cancer cells were enhanced by miR-887 mimics and suppressed by miR-887 inhibitor. Compared with control mice, the volume and weight of subcutaneous tumors of mice in the miR-887 mimics group were significantly elevated, and the significant increase was found in the occurrence of lung metastasis. Moreover, bioinformatics tools showed that miR-887 and VHL had 2 binding sites. Luciferase activity assay demonstrated that miR-887 can inhibit the luciferase activity of VHL, and miR-887 mimics could reduce the expressions of VHL at both messenger RNA and protein levels to increase hypoxia-inducible factor α expression. CONCLUSION: The upregulation of miR-887 could facilitate the proliferation and metastasis of hepatocellular carcinoma cells via targeting VHL.

15.
Artigo em Inglês | MEDLINE | ID: mdl-32779064

RESUMO

The frequent occurrence of microcystins (MCs) in freshwater poses serious threats to the drinking water safety and health of human beings. Although MCs have been detected in individual fresh waters in China, little is known about their occurrence over a large geographic scale. An investigation of 30 subtropical lakes in eastern China was performed during summer 2018 to determine the MCs concentrations in water and their possible risk via direct water consumption to humans, and to assess the associated environmental factors. MCs were detected in 28 of 30 lakes, and the highest mean MCs concentrations occurred in Lake Chaohu (26.7 µg/L), followed by Lake Taihu (3.11 µg/L). MC-LR was the primary variant observed in our study, and MCs were mainly produced by Microcystis, Anabaena (Dolicospermum), and Oscillatoria in these lakes. Replete nitrogen and phosphorus concentrations, irradiance, and stable water column conditions were critical for dominance of MC-producing cyanobacteria and high MCs production in our study. Hazard quotients indicated that human health risk of MCs in most lakes was at moderate or low levels except Lakes Chaohu and Taihu. Nutrient control management is recommended to decrease the likelihood of high MCs production. Finally, we recommend the regional scale thresholds of total nitrogen and total phosphorus concentrations of 1.19 mg/L and 7.14 × 10-2 mg/L, respectively, based on the drinking water guideline of MC-LR (1 µg/L) recommended by World Health Organization. These targets for nutrient control will aid water quality managers to reduce human health risks created by exposure to MCs.

16.
Phys Rev E ; 102(1-1): 012219, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32794968

RESUMO

We systematically study dynamics of a generalized Kuramoto model of globally coupled phase oscillators. The coupling of modified model depends on the fraction of phase-locked oscillators via a power-law function of the Kuramoto order parameter r through an exponent α, such that α=1 corresponds to the standard Kuramoto model, α<1 strengthens the global coupling, and the global coupling is weakened if α>1. With a self-consistency approach, we demonstrate that bifurcation diagrams of synchronization for different values of α are thoroughly constructed from two parametric equations. In contrast to the case of α=1 with a typical second-order phase transition to synchronization, no phase transition to synchronization is predicted for α<1, as the onset of partial locking takes place once the coupling strength K>0. For α>1, we establish an abrupt desynchronization transition from the partially (fully) locked state to the incoherent state, whereas there is no counterpart of abrupt synchronization transition from incoherence to coherence due to that the incoherent state remains linearly neutrally stable for all K>0. For each case of α, by performing a standard linear stability analysis for the reduced system with Ott-Antonsen ansatz, we analytically derive the continuous and discrete spectra of both the incoherent state and the partially (fully) locked states. All our theoretical results are obtained in the thermodynamic limit, which have been well validated by extensive numerical simulations of the phase-model with a sufficiently large number of oscillators.

17.
Artigo em Inglês | MEDLINE | ID: mdl-32811144

RESUMO

Perfluoroalkyl substances (PFASs), such as perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), can contaminate the surface and groundwater. Common treatment strategies and adsorbents have low adsorption efficiencies and poor selectivity toward PFASs because of the extremely low surface energy of these compounds. This paper reports the use of a phenolic resin (PR) modified with perfluoroalkyl (PFA) segments and thermally sensitive poly(ethylene glycol) (PEG) segments (PR-PEG-PFA) to remove PFOA and PFOS from water. The modified PR microspheres captured >90% of PFASs and were insensitive to common anionic surfactants. By treating simulated wastewater six times with this material, the PFOA concentration in water was reduced from 1 ppm to 43 ppt (43 ng L-1), showing that PR-PEG-PFA is a promising adsorbent for PFAS separation, recovery, and recycling.

18.
Environ Sci Technol ; 54(19): 12295-12306, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-32852947

RESUMO

The increasing applications of single-layer molybdenum disulfide (SLMoS2) pose great potential risks associated with environmental exposure. This study found that metallic-phase SLMoS2 with nanoscale (N-1T-SLMoS2, ∼400 nm) and microscale (M-1T-SLMoS2, ∼3.6 µm) diameters at 10-25 mg/L induced significant algal growth inhibition (maximum 72.7 and 74.6%, respectively), plasmolysis, and oxidative damage, but these alterations were recoverable. Nevertheless, membrane permeability, chloroplast damage, and chlorophyll biosynthesis reduction were persistent. By contrast, the growth inhibition (maximum 55.3%) and adverse effects of nano-sized semiconductive-phase SLMoS2 (N-2H-SLMoS2, ∼400 nm) were weak and easily alleviated after 96 h of recovery. N-1T-SLMoS2 (0.011 µg/h) and N-2H-SLMoS2 (0.008 µg/h) were quickly biodegraded to soluble Mo compared with M-1T-SLMoS2 (0.004 µg/h) and excreted by algae. Incomplete biodegradation of SLMoS2 (26.8-43.9%) did not significantly mitigate its toxicity. Proteomics and metabolomics indicated that the downregulation of proteins (50.7-99.2%) related to antioxidants and photosynthesis and inhibition of carbon fixation and carbohydrate metabolism contributed to the persistent phytotoxicity. These findings highlight the roles and mechanisms of the size and phase in the persistent phytotoxicity of SLMoS2, which has potential implications for risk assessment and environmental applications of nanomaterials.

19.
J Ethnopharmacol ; 265: 113264, 2020 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-32846192

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Herba Patriniae has been used for thousands of years in China as a traditional Chinese medicine with heat-clearing and detoxicating effects. It is applied widly for the treatment of rheumatoid arthritis, diarrhea, acute hepatitis, pelvic inflammatory disease and ulcerative colitis in clinic. Two species, namely Patrinia scabiosaefolia Fisch. (PS) and Patrinia villosa Juss. (PV) from the Caprifoliaceae family, are considered as Herba Patriniae in the pharmaceutical industry. AIM OF THE REVIEW: This paper aims to comprehensively outline the traditional uses, botanical description, phytochemistry, pharmacology, toxicology, quality control, pharmacokinetics and patents of Herba Patriniae, and elaborate the same/different characteristics between PS and PV. MATERIALS AND METHODS: Detailed information of Herba Patriniae was collected from various online databases (Pubmed, Web of Science, Google Schola, China National Knowledge Infrastructure Database, National Intellectual Property Administration, PRC National Medical Products Administration), and those published resources (M.Sc. Thesis and books). RESULTS: A total of 233 compounds have been identified in Herba Patriniae, including triterpenoid saponins, flavonoids, organic acids, iridoids, and volatiles. A very distinct difference was observed, that PS is rich in triterpenoid saponins and volatiles, while PV contains more flavonoids. Two source species of Herba Patriniae gave similar pharmacological effects on anti-cancer, anti-inflammatory, antioxidant, antimicrobial, sedative and hypnotic effects. But there were no reports were on antipruritic, proangiogenic and anti-diarrheal effects for PS, and no studies on anti-diabetic effects for PV. Generally, Herba Patriniae showed non-toxic in the clinical dose, but mild side effects, such as temporary leukopenia, dizziness and nausea, could be found when large and excessive dosage is used. A variety of compounds have been quantified for the quality control of PS and PV. The variety, growth environment, growth time, and harvest time not only affected the contents but also the pharmacological activities of the bioactive compounds. In the past year, patents for compositions containing PV and PS have been filed, mainly involving human health, hygiene, agriculture, and animal husbandry. Unfortunately, the research on pharmacokinetics is insufficient. Only the prototype components and metabolites were repored after intragastric administration of total flavonoids extract from PV in rats. CONCLUSION: Herba Patriniae has displayed a significant medicinal value in clinic, but the differences in phytochemistry, pharmacological effects and the content of compounds have been found between two official recorded species. About side effects and pharmacokinetic characteristics, the differences between two species have not been well studied. For a better clinical use of Herba Patriniae, it is urgent to establish systematic pharmacology, quality control, pharmacokinetics, and clinical researches on the same/different characteristics between PS and PV.

20.
Talanta ; 218: 121128, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32797885

RESUMO

A novel and sensitive method for the selective determination of Cr(VI) and non-chromatographic speciation of Cr(VI) and Cr(III) was developed based on chemical vapor generation (CVG) in KBH4-acid system for sample introduction into an inductively coupled plasma mass spectrometer (ICP-MS) for detection. The CVG of Cr(VI), rather than Cr(III), was found to be remarkably enhanced in the presence of sodium diethylaminodithioformate (DDTC). After the oxidation of Cr(III) to Cr(VI) by KMnO4, the quantitation of Cr(III) could be obtained based on the difference between the concentration of total chromium and that of Cr(VI). Parameters affecting the CVG reaction and determination of Cr(VI) were evaluated in detail, including the concentrations of DDTC, hydrochloric acid and KBH4, the sample flow rate, as well as the length of reaction and transferring tubing. Under optimal conditions, the CVG efficiency and the limit of detection (LOD) of Cr(VI) were found to be 28% and 0.2 ng mL-1, respectively. The relative standard deviations for seven replicate measurements of 20 ng mL-1 of Cr(Ⅵ) was 1.8%. Furthermore, with excess DDTC (100 µg mL-1) added to the test solutions, possible interferences from Cu2+ (up to 400 ng mL-1) could be eliminated. The proposed method was thus successfully applied to the determination of Cr(VI) in three real water samples and one certified reference water sample, as well as two simulated water samples of Cr(VI) and Cr(III), all with satisfactory results. The possible reasons were discussed for the varied degrees of enhancement between Cr(III) and Cr(VI).

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