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1.
Int J Geriatr Psychiatry ; 39(1): e6047, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38161286

RESUMO

OBJECTIVES: Chronic hyperglycemia is considered as an important factor to promote the neurodegenerative process of brain, and the synaptic plasticity as well as heterogeneity of hippocampal cells are thought to be associated with cognitive dysfunction in the early process of neurodegeneration. To date, fibronectin type III domain-containing protein 5 (FNDC5) has been highlighted its protective role in multiple neurodegenerative diseases. However, the potential molecular and cellular mechanisms of FNDC5 on synaptic plasticity regulation in cognitive impairment (CI) induced by diabetics are still need to known. METHODS/DESIGN: To investigate the heterogeneity and synaptic plasticity of hippocampus in animals with CI state induced by hyperglycemia, and explore the potential role of FNDC5 involved in this process. Firstly, the single cell sequencing was performed based on the hippocampal tissue from db diabetic mice induced CI and normal health control mice by ex vivo experiments; and then the integrated analysis and observations validation using Quantitative Real-time PCR, western blot as well as other in vitro studies. RESULTS: We observed and clarified the sub-cluster of type IC spiral ganglion neurons expressed marker genes as Trmp3 and sub-cluster of astrocytes with marker gene as Atp1a2 in hippocampal cells from diabetic animals induced CI and the effect of those on neuron-glial communication. We also found that FNDC5\BDNF-Trk axis was involved in the synaptic plasticity regulation of hippocampus. In high glucose induced brain injury model in vitro, we investigated that FNDC5 significantly regulates BDNF expression and that over-expression of FNDC5 up-regulated BDNF expression (p < 0.05) and can also significantly increase the expression of synapsin-1 (p < 0.05), which is related to synaptic plasticity, In addition, the unbalanced methylation level between H3K4 and H3K9 in Fndc5 gene promoter correlated with significantly down-regulated expression of FNDC5 (p < 0.05) in the hyperglycemia state. CONCLUSION: The current study revealed that the synaptic plasticity of hippocampal cells in hyperglycemia might be regulated by FNDC5\BDNF-Trk axis, playing the protective role in the process of CI induced by hyperglycemia and providing a target for the early treatment of hyperglycemia induced cognitive dysfunction in clinic.


Assuntos
Disfunção Cognitiva , Diabetes Mellitus Experimental , Fibronectinas , Hiperglicemia , Animais , Humanos , Camundongos , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Cognição , Disfunção Cognitiva/genética , Disfunção Cognitiva/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Fibronectinas/genética , Fibronectinas/metabolismo , Hipocampo , Hiperglicemia/metabolismo , Plasticidade Neuronal/fisiologia , ATPase Trocadora de Sódio-Potássio/metabolismo
2.
Environ Toxicol ; 39(5): 2893-2907, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38299319

RESUMO

BACKGROUND: N6-Methyladenosine (m6A) RNA methylation modulators are implicated in nasopharyngeal carcinoma (NPC). Circular RNAs (circRNAs) stimulate/inhibit the development of NPC by sponging microRNAs (miRNAs). Herein, m6A modifications affecting the circRNA/miRNA axis in NPC were explored. METHODS: Twenty prognostic m6A RNA methylation regulators were identified from 504 head/neck squamous cell carcinoma and 44 normal samples from The Cancer Genome Atlas (TCGA). Differentially expressed miRNAs were screened from the TCGA and Gene Expression Omnibus (GEO) databases. RNA-binding protein (RBP)-circRNA and circRNA-miRNA interactive pairs were verified using RBPmap and RNAhybrid, respectively. The RBP/circRNA/miRNA network was constructed using Cytoscape. Furthermore, CircITCH (hsa_circ_00059948), HNRNPC, and miR-224-3p expressions were detected by western blotting and quantitative polymerase chain reaction. The role of circITCH in NPC was examined using apoptosis, scratch wound healing, transwell invasion, and cell counting kit-8 assays. Finally, CircITCH-miR-224-3p and circITCH-HNRNPC interactions were assessed by dual-luciferase reporter and RNA-immunoprecipitation (RIP) assays, respectively. RESULTS: Bioinformatics analysis revealed that high pathological grade, late-stage tumors, and low survival were associated with increased HNRNPC expression. MiR-224-3p was upregulated in NPC and sequestered by circITCH. Construction of the RBP/circRNA/miRNA network highlighted the HNRNPC/circITCH/miR-224-3p axis. In vitro experiments demonstrated decreased circITCH expression and increased HNRNPC and miR-224-3p expressions in NPC. In NPC cells overexpressing circITCH, HNRNPC and miR-224-3p expressions were significantly decreased. Dual-luciferase assays demonstrated a targeting relationship between circITCH and miR-224-3p, and RIP assays demonstrated interaction of HNRNPC targets with circITCH. CONCLUSION: CircITCH overexpression inhibited NPC progression by sequestering miR-224-3p, and HNRNPC reduced circITCH expression through direct interaction.


Assuntos
MicroRNAs , Neoplasias Nasofaríngeas , Humanos , Regulação para Baixo/genética , Carcinoma Nasofaríngeo/genética , RNA Circular/genética , Carcinogênese/genética , Transformação Celular Neoplásica , Luciferases , MicroRNAs/genética , Linhagem Celular Tumoral , Proliferação de Células , Ribonucleoproteínas Nucleares Heterogêneas Grupo C/genética
3.
BMC Surg ; 24(1): 103, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600472

RESUMO

BACKGROUND: There is no effective consensus on the choice of internal fixation method for the Masquelet technique in the treatment of large segmental bone defects of the distal tibia. Thus, the study aimed to investigate the outcomes of the Masquelet technique combined with double plate fixation in the treatment of large segmental bone defects. METHODS: This was a retrospective study involving 21 patients with large segmental bone defects of the distal tibia who were treated between June 2017 and June 2020. The length of bone defect ranged from 6.0 cm to 11 cm (mean, 8.19 cm). In the first stage of treatment, following complete debridement, a cement spacer was placed to induce membrane formation. In the second stage, double plate fixation and autologous cancellous bone grafting were employed for bone reconstruction. Each patient's full weight-bearing time, bone healing time, and Iowa ankle score were recorded, and the occurrence of any complications was noted. RESULTS: All patients were followed up for 16 to 26 months (mean, 19.48 months). The group mean full weight-bearing time and bone healing time after bone grafting were 2.41 (± 0.37) months and 6.29 (± 0.66) months, respectively. During the treatment, one patient had a wound infection on the medial side of the leg, so the medial plate was removed. The wound completely healed after debridement without any recurrence. After extraction of iliac bone for grafting, one patient had a severe iliac bone defect, which was managed by filling the gap with a cement spacer. Most patients reported mild pain in the left bone extraction area after surgery. The postoperative Iowa ankle score range was 84-94 (P < 0.05). In this cohort, 15 cases were rated as "excellent", and 6 cases as "good" on the Iowa ankle scoring system. CONCLUSION: The Masquelet technique combined with double plate fixation is a safe and effective method for the treatment of large segmental bone defects of the distal tibia.


Assuntos
Procedimentos de Cirurgia Plástica , Fraturas da Tíbia , Humanos , Tíbia/cirurgia , Estudos Retrospectivos , Extremidade Inferior/cirurgia , Fixação Interna de Fraturas , Transplante Ósseo/métodos , Resultado do Tratamento , Fraturas da Tíbia/cirurgia
4.
Environ Sci Technol ; 57(47): 18586-18596, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36912755

RESUMO

Fenton processes produce reactive species that can oxidize organic compounds in natural and engineered systems. While it is well-documented that Fenton reactions produce hydroxyl radical (HO•) under acidic conditions, we demonstrated the generation of ferryl ion (FeIVO2+) in the UV/Fe(III) and UV/Fe(III)/H2O2 systems at pH 2.8 using methyl phenyl sulfoxide (PMSO) as the probe compound. Moreover, we clarified that FeIVO2+ is parallelly formed via the oxidation of Fe(III) by HO• and the O-O homolysis of [FeIII-OOH]2+ in the photo-Fenton process. The rate constant for the reaction between HO• and Fe3+ measured by laser flash photolysis was 4.41 × 107 M-1 s-1. The rate constant and quantum yield for thermal and photo O-O homolysis of [FeIII-OOH]2+ complex were 1.4 × 10-2 s-1 and 0.3, respectively, which were determined by fitting PMSO2 formation. While FeIVO2+ forms predominantly through the reaction between HO• and Fe3+ in the absence of H2O2, the relative contribution of [FeIII-OOH]2+ O-O homolysis to FeIVO2+ formation highly depends on the molar ratio of [H2O2]0/[Fe(III)]0, the level of HO• scavenging, and incident irradiance in the UV/Fe(III)/H2O2 system. Accordingly, an optimized kinetic model was developed by incorporating FeIVO2+-involved reactions into the conventional photo-Fenton model, which can accurately predict Fe(II) formation and contaminant decay in the UV/Fe(III) and UV/Fe(III)/H2O2 systems. Our study illuminated the underlying formation mechanism of reactive oxidative species in the photo-Fenton process and highlighted the role of FeIVO2+ evolution in modulating the iron cycle and pollutant abatement therein.


Assuntos
Compostos Férricos , Peróxido de Hidrogênio , Compostos Férricos/química , Peróxido de Hidrogênio/química , Ferro/química , Oxirredução , Concentração de Íons de Hidrogênio
5.
Blood Purif ; 52(7-8): 609-620, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37591223

RESUMO

BACKGROUND: Hyperphosphatemia is associated with cardiovascular morbidity and mortality in adults with chronic kidney disease (CKD). Drug therapy has an irreplaceable role in the management of hyperphosphatemia. OBJECTIVES: We aimed to compare and rank phosphorus-lowering drugs, including phosphate binder and nonphosphate binder, in hyperphosphatemia adults with CKD. METHODS: We did a systematic review and frequentist random-effect network meta-analysis. We searched in PubMed, Cochrane Library, Web of Science, and Embase from inception to February 1, 2023, for randomized controlled trials of 12 phosphorus-lowering drugs in adults with hyperphosphatemia and CKD. Primary outcomes were efficacy (changes in serum phosphorus) and acceptability (treatment withdrawals due to any cause). We ranked each drug according to the value of surface under the cumulative ranking curve. We applied the Confidence in Network Meta-Analysis frameworks to rate the certainty of evidence. This study was registered with PROSPERO, number CRD42022322270. RESULTS: We identified 2,174 citations, and of these, we included 94 trials comprising 14,459 participants and comparing 13 drugs or placebo. In terms of efficacy, except for niacinamide, all drugs lowered the level of serum phosphorus compared with placebo, with mean difference ranging between -1.61 (95% credible interval [CrI], -2.60 to -0.62) mg/dL for magnesium carbonate and -0.85 (-1.66 to -0.05) mg/dL for bixalomer. Only ferric citrate with odds ratios 0.56 (95% CrI: 0.36-0.89) was significantly associated with fewer dropouts for acceptability. Of the 94 trials, 43 (46%), 7 (7%), and 44 (47%) trials were rated as high, moderate, and low risk of bias, respectively, the certainty of the evidence was moderate to very low. CONCLUSIONS: Magnesium carbonate has the best phosphorus-lowering effect in hyperphosphatemia adults with CKD; considering efficacy and acceptability, ferric citrate shows evidence to be the most appropriate drug with or without dialysis.


Assuntos
Hiperfosfatemia , Insuficiência Renal Crônica , Humanos , Adulto , Hiperfosfatemia/tratamento farmacológico , Hiperfosfatemia/etiologia , Metanálise em Rede , Diálise Renal , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/tratamento farmacológico
6.
Arch Virol ; 167(3): 969-972, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35112200

RESUMO

Nematodes are abundant, but little is known about their viruses. In this study, we report a novel partitivirus isolated from the entomopathogenic nematode species Steinernema ceratophorum, named "Steinernema ceratophorum partitivirus 1" (ScPV-1). The complete genome of ScPV-1 comprises two dsRNA segments, dsRNA1 (2352 bp) and dsRNA2 (2196 bp). Each dsRNA contains a single open reading frame (ORF), encoding a putative RNA-dependent RNA polymerase (RdRp) and a coat protein (CP), respectively. The sequences of the RdRp and CP showed the highest similarity (47% and 33% identity, respectively) to Plasmopara viticola associated partitivirus 7 (PvAP-7). A multiple sequence alignment and phylogenetic analysis of the RdRp of ScPV-1 and other selected viruses indicated that ScPV-1 is a new member of the genus Betapartitivirus in the family Partitiviridae.


Assuntos
Nematoides , Vírus de RNA , Animais , Genoma Viral , Nematoides/genética , Filogenia , Vírus de RNA/genética , RNA Viral/genética
7.
Environ Sci Technol ; 56(20): 14788-14796, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36154007

RESUMO

Scaling-induced wettinggreatly limits the application of membrane distillation (MD) for the desalination of high-salinity feed. Although highly soluble salts (e.g., NaCl) have high concentrations in this water, their scaling-induced wetting remains overlooked. To unravel the elusive wetting behaviors of highly soluble salts, in this study, we systematically investigated the scaling formation and wetting progress by in situ observation with optical coherence tomography (OCT). Through examining the influence of salt type and vapor flux on the wetting behavior, we revealed that highly soluble salt-induced wetting, especially under high vapor flux, shared several unique features: (1) occurring before the bulk feed reached saturation, (2) no scale layer formation observed, and (3) synchronized wetting progress on the millimeter scale. We demonstrated that a moving scale layer caused these interesting phenomena. The initial high vapor flux induced high concentration and temperature polarizations, which led to crystallization at the gas-liquid interface and the formation of an initial scale layer. On the one hand, this scale layer bridged the water into the hydrophobic pores; on the other hand, it blocked the membrane pores and reduced the vapor flux. In this way, the decreased vapor flux mitigated the concentration/temperature polarizations, and consequently led to the dissolution of the feed-facing side of the scale layer. This dissolution prevented the membrane pores from being completely blocked, facilitating the transportation and crystallization of salts at the distillate-facing side of the scale layer (i.e., the gas-liquid interface), thus the proceeding of the wetting layer.


Assuntos
Destilação , Purificação da Água , Destilação/métodos , Membranas Artificiais , Sais/química , Cloreto de Sódio , Cloreto de Sódio na Dieta , Água , Purificação da Água/métodos
8.
Environ Sci Technol ; 56(1): 556-563, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34928146

RESUMO

In this study, we performed a direct contact membrane distillation and successfully demonstrated the non-invasive imaging of surfactant-induced wetting using optical coherence tomography. This method enabled us to investigate the wetting kinetics, which was found to follow a "three-region" relationship between the wetting rate and surfactant concentration: the (i) nonwetted region, (ii) concentration-dependent region, and (iii) concentration-independent region at low, intermediate, and high surfactant concentrations, respectively. This wetting behavior was explained by the "autophilic effect", i.e., the wetting was caused by the transfer of surfactants from the water-vapor interface to the unwetted membrane and rendered this membrane hydrophilic, and then the wetting frontier moved forward under capillary forces. At region-(i), the surfactant concentration in the water-vapor interface (Clv) was too low to make the unwetted membrane sufficiently hydrophilic; thereby, the membrane could not be wetted. At region-(ii), due to the fast adsorption of the surfactant on the newly wetted membrane, the wetting rate was determined by the advection/diffusion of surfactants from the feed stream. Consequently, the wetting rate increased with the increases in the water flux and surfactant concentration. At region-(iii), the advection/diffusion provided excess surfactants for adsorption, and thus Clv reached its upper limit (maximum surface excess) and the wetting rate leveled off.


Assuntos
Tensoativos , Purificação da Água , Cinética , Membranas Artificiais , Tomografia de Coerência Óptica
9.
Cell Biochem Funct ; 39(4): 488-495, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33432584

RESUMO

Hyaluronic acid (HA) exerts a critical role in the lubricating and buffering properties of synovial fluid in joints. The production of HA is regulated by growth factors, hormones, inflammatory cytokines and mechanical load. The reduction of HA contributes to the progression of osteoarthritis. Herein, we found that d-galactose (d-gal) induced the senescence of rabbit synovial membrane cells, accompanied by decreased HA production. The mRNA level of HA synthase 2 (HAS2) was downregulated by d-gal, as analysed by real-time polymerase chain reaction. Melatonin, an endocrine hormone, can regulate the homeostasis of bone and cartilage. We found that melatonin treatment attenuated d-gal-induced cell senescence and decreased the expression of p21, p16 and pp65 proteins. Melatonin could reverse HA production and maintain HAS2 expression. Furthermore, we revealed that Sirt1 signalling was required for melatonin effects. Sirt1 inhibitor could counteract melatonin-mediated HA production and HAS2 expression. Additionally, Sirt1 overexpression directly antagonized d-gal-induced cell aging and HA downregulation. Taken together, our results suggest that melatonin-Sirt1 signal has a protective effect on synovial membrane cells, enhancing HA synthesis and interrupting cell senescence.


Assuntos
Galactose/antagonistas & inibidores , Ácido Hialurônico/biossíntese , Melatonina/farmacologia , Sirtuína 1/metabolismo , Membrana Sinovial/efeitos dos fármacos , Sinoviócitos/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Senescência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Galactose/metabolismo , Ácido Hialurônico/antagonistas & inibidores , Masculino , Coelhos , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/genética , Membrana Sinovial/citologia , Sinoviócitos/metabolismo , Regulação para Cima/efeitos dos fármacos
10.
Med Sci Monit ; 27: e932772, 2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34625526

RESUMO

Most cancer deaths are caused by metastasis. The phosphocreatine 3- kinase (PI3K) family includes the I-III classes, with class I divided into 4 subtypes (alpha, ß, γ, delta); and PI3K signaling participates in the regulatory processes of cell proliferation, differentiation, apoptosis, and glucose transport. Moreover, PI3Ks are modulators of cellular membrane lipids involved in signaling and trafficking events. The PI3Kdelta isoform (PI3Kdelta), which is not only specifically expressed in hematopoietic cells, but also in different tumor cell lines, is expressed extensively. The increase in PI3Kdelta activity is often associated with a variety of cancers. Currently, the strategy of tumor therapy based on PI3Kd and its related signaling pathway is developing. Besides its established role in controlling functions in autoimmunity and inflammation, the role of PI3Kdelta in tumor and metastasis is not clearly elucidated, with the effects of inhibiting PI3Kdelta in several types of tumors also remaining unexplored. In addition, the specific inhibitor of PI3Kdelta in tumor progression and metastasis and its underlying mechanism need to be further studied. The purpose of this review is to rationalize the existing functions and mechanisms of PI3Kdelta in tumor metastasis and the relationship with hematopoietic cells in cancers as well cross-talking with miRNA, which provides a new theoretical basis and potential therapeutic target for the drug therapy of tumor metastasis.


Assuntos
Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias/tratamento farmacológico , Inibidores de Fosfoinositídeo-3 Quinase/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Animais , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Carcinogênese/patologia , Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Classe I de Fosfatidilinositol 3-Quinases/genética , Modelos Animais de Doenças , Humanos , Camundongos , Mutação , Neoplasias/genética , Neoplasias/patologia , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Medicina de Precisão/métodos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/genética
11.
J Acoust Soc Am ; 150(3): 1652, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34598632

RESUMO

Broadband sound absorption performance and high mechanical strength are major concerns for designing a microperforated plate (MPP) absorber, which is generally difficult to achieve for a single-layer MPP with straight holes. A MPP was proposed with variable cross-sectional holes, including large dents on one side, grooves on the other side, and intermediate micro-slits. The beneficial effects of the special geometrical features are thoroughly discussed and experimentally validated. Models to calculate the acoustic impedance are established, and acoustic behaviors within holes are simulated. It was found that the micro-slits could provide necessary acoustic resistance for impedance matching and very low reactance to expand sound absorption bandwidth. The large dents or grooves could provide the necessary thickness with negligible acoustic impedance to enhance plate mechanical strength. This research helps to implement a single-layer MPP design with good acoustical and mechanical performance.

12.
J Acoust Soc Am ; 150(1): 410, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34340466

RESUMO

The membrane sound absorber (MSA) with a compact magnet has exhibited excellent tunable properties for low-frequency sound absorption. To further clarify its acoustic properties, this paper presents a theoretical model based on a multi-mechanism coupling impedance method. The model predicts the absorption coefficients and resonant frequencies of the MSA at different tuning magnetic states for three cavity configurations. These parameters are then experimentally measured using an impedance tube for model validation, demonstrating good agreement between the measured and predicted values. Subsequent analysis reveals the iron-platelet-magnet resonance mechanism introduced by the tuned magnetic field is the main factor behind the appearance and shift of absorption peaks in the low-frequency region, which are mostly independent of the back cavity. In other words, the MSA with a back cavity of any size can achieve sound absorption in the low-frequency region. This demonstrates the potential of the structure in achieving an ultra-thin, low-frequency, tunable sound-absorber design that can be adapted to different noise sources.

13.
J Environ Manage ; 298: 113431, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34352480

RESUMO

Nitritation-anammox has been considered to be the most promising process for nitrogen (N) removal from wastewater. However, the anammox reaction still produces an amount of nitrate, which cannot be removed further. This study hypothesizes that heterotrophic denitrification can be an appealing option to remove the residual nitrate in the one-stage nitritation-anammox process. Through monitoring N-removal performance and microbial community succession of a laboratory microaerobic reactor, the effect of four different levels of oxygen supply on nitrate removal was investigated. The reactor was continuously fed with real manure-free piggery wastewater containing ~240 mg NH4+-N/L and chemical oxygen demand (COD)/total nitrogen (TN) ratio of less than 1 for 180 days. With a high influent loading rate of 0.7 kg N/(m3·d), efficient total nitrogen removal (>80 %) was achieved during stable operation of dissolved oxygen (DO) concentrations between 0.3 and 0.6 mg O2/L, indicating N-removal via the nitritation-anammox pathway in the low-carbon wastewater treatment. At the same time, the effluent nitrate reduced with decreased oxygen supply and completely depleted at DO of 0.3 ± 0.1 mg O2/L. In addition to oxygen, preventing ammonia nitrogen from falling to very low levels (<10 mg/L) could be also useful for the complete nitrate removal and stable nitritation-anammox. 16S rRNA gene-based analyses confirmed a complex microbial community including nitrifiers, denitrifiers and anammox bacteria in the biomass of the reactor. Collectively, this study provides new insights into high-level N-removal of a nitritation-anammox process by complete nitrate depletion.


Assuntos
Desnitrificação , Nitratos , Reatores Biológicos , Nitratos/análise , Nitrogênio , Oxirredução , RNA Ribossômico 16S , Águas Residuárias
14.
Environ Sci Technol ; 54(24): 15563-15583, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33213143

RESUMO

The separation properties of polyamide reverse osmosis and nanofiltration membranes, widely applied for desalination and water reuse, are constrained by the permeability-selectivity upper bound. Although thin-film nanocomposite (TFN) membranes incorporating nanomaterials exhibit enhanced water permeance, their rejection is only moderately improved or even impaired due to agglomeration of nanomaterials and formation of defects. A novel type of TFN membranes featuring an interlayer of nanomaterials (TFNi) has emerged in recent years. These novel TFNi membranes show extraordinary improvement in water flux (e.g., up to an order of magnitude enhancement) along with better selectivity. Such enhancements can be achieved by a wide selection of nanomaterials, ranging from nanoparticles, one-/two-dimensional materials, to interfacial coatings. The use of nanostructured interlayers not only improves the formation of polyamide rejection layers but also provides an optimized water transport path, which enables TFNi membranes to potentially overcome the longstanding trade-off between membrane permeability and selectivity. Furthermore, TFNi membranes can potentially enhance the removal of heavy metals and micropollutants, which is critical for many environmental applications. This review critically examines the recent developments of TFNi membranes and discusses the underlying mechanisms and design criteria. Their potential environmental applications are also highlighted.


Assuntos
Nanocompostos , Filtração , Membranas Artificiais , Nylons , Permeabilidade
15.
Biomed Chromatogr ; 34(9): e4866, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32330998

RESUMO

A reliable and sensitive UPLC-MS/MS method was first established and validated for the simultaneous determination of seven active ingredients of Yaobitong capsule in rat plasma: ginsenoside Rg1, ginsenoside Rb1, osthole, tetrahydropalmatine, paeoniflorin, albiflorin, and ferulic acid. And this method was further applied for the integrated pharmacokinetic study of Yaobitong capsule in rats after oral administration. Plasma samples (100 µL) were precipitated with 300 µL of methanol using carbamazepine as internal standard. Chromatographic separation was achieved using an Aquity UPLC BEH C18 column (100 × 2.1 mm, 1.7 µm), with the mobile phase consisting of 0.1% formic acid and acetonitrile. The method was validated using a good linear relationship (r ≥ 0.991), and the lower limit of quantification of the analytes ranged from 0.5 to 40 ng/mL. In the integrated pharmacokinetic study, the weight coefficient was calculated by the ratio of AUC0-∞ of each component to the total AUC0-∞ of the seven active ingredients. The integrated pharmacokinetic parameters Cmax , Tmax , and t1/2 were 81.54 ± 9.62 ng/mL, 1.00 ± 0.21 h, and 3.26 ± 1.14 h, respectively. The integration of pharmacokinetic parameters showed a shorter t1/2 because of fully considering the contribution of the characteristics of each active ingredient to the overall pharmacokinetics.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas , Glucosídeos/sangue , Monoterpenos/sangue , Espectrometria de Massas em Tandem/métodos , Animais , Alcaloides de Berberina/sangue , Alcaloides de Berberina/química , Alcaloides de Berberina/farmacocinética , Ácidos Cumáricos/sangue , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacocinética , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacocinética , Glucosídeos/química , Glucosídeos/farmacocinética , Modelos Lineares , Masculino , Monoterpenos/química , Monoterpenos/farmacocinética , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
J Acoust Soc Am ; 148(2): 566, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32873030

RESUMO

An additional length model is usually used to describe the reactive part of the impedance end correction of microperforated panels, which is extended to describe the resistive part. The cross-sectional impedance is computed along the axis of one perforation cell with a circular hole. Except for the obvious jumps in the narrow regions at the inlet and outlet of the perforation, the impedance varies linearly along the axis following exactly that of the viscous wave in the circular hole. The additional length for the impedance end correction is obtained by extrapolating the linearly varying impedance inside the hole. Empirical models for the resistive and reactive additional lengths are obtained based on the thermoviscous acoustic simulation with 96 test cases. Within an error of about 10%, a unified additional length model is presented for both the resistive and reactive parts of the impedance end correction. Comparison with other existing models shows the accuracy of the proposed model.

17.
J Acoust Soc Am ; 147(2): EL113, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32113307

RESUMO

This Letter presents a monostable acoustic metamaterial that has the potential to implement broadband sound absorption in low frequencies. The proposed metamaterial is realized by placing a flexible panel with a magnetic proof mass in a symmetric magnetic field. A theoretical model of the metamaterial is established and experimentally validated. Predictions and measurements demonstrate that the sound absorption peak frequency significantly shifts downwards with the increasing magnetic field. The relative bandwidth of the metamaterial is also broadened with the increasing magnetic field due to its inverse proportionality to the absorption peak frequency.

18.
J Acoust Soc Am ; 145(5): EL400, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31153345

RESUMO

In this letter, a membrane-type acoustic metamaterial with a compact magnet (MAMM) is presented. To investigate its frequency-tunable properties, a theoretical model considering both static and dynamic effects of magnetic force is established. Analytical investigations indicate that tuning of the magnetic force exerted on the centralized rigid iron platelet leads to the shift in the MAMM's transmission loss peaks. The experimental anti-resonance frequencies of the MAMM derived from the impedance tube measurements exhibited good consistency with those predicted theoretically. Continuously tuned in a wide frequency range, this structure can well adapt to the noise source variation in insulation design.

19.
Chirality ; 30(12): 1321-1329, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30375664

RESUMO

In this study, magnetic multiwalled carbon nanotubes (MMWCNTs) were synthesized and used as adsorbent for preconcentration of chiral pesticide residues (including epoxiconazole, tebuconazole, and metalaxyl) in lettuce, cabbage, and apple. Several parameters affecting the treatment efficiency were investigated, including extraction solvent and absorption solvent. Under the optimal conditions, all three chiral pesticides showed decent enantiomeric separation (Rs > 1.48). The linearity of each target was good with the correlation coefficient (r2 ) being greater than 0.9923. The average recoveries of the three spiked levels were 73.4% to 110.9% with repeatability (RSDr ) less than 7.6%, and the limit of quantification of the method was 0.10 to 0.25 mg·kg-1 . The results indicated that MMWCNTs had a good purifying effect, which can be applied as an effective pretreatment tool for the determination of residual chiral pesticides in fruits and vegetables.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , Nanotubos de Carbono/química , Resíduos de Praguicidas/análise , Verduras/química , Alanina/análogos & derivados , Alanina/análise , Calibragem , Fracionamento Químico/instrumentação , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão/instrumentação , Compostos de Epóxi/análise , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Magnetismo , Resíduos de Praguicidas/química , Resíduos de Praguicidas/isolamento & purificação , Reprodutibilidade dos Testes , Solventes , Espectroscopia de Infravermelho com Transformada de Fourier , Estereoisomerismo , Triazóis/análise
20.
Biol Pharm Bull ; 40(9): 1352-1360, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28867720

RESUMO

Rapamycin (Rap) has been demonstrated to affect lipid metabolism through stimulating lipolysis, inhibiting de novo lipogenesis and reducing adiposity. In the present study, we investigated rapamycin exposure's influence on adipose tissue browning in high-fat diet-induced fatty mice. Four-week old C57BL/6J mice were fed normal chow or high-fat diet for a period of 6 weeks and then divided into three groups: (1) Nor group: mice fed with normal chow; (2) high fat diet (HFD) group: fatty mice fed with high-fat diet; (3) Rap group: high-fat diet-fed fatty mice treated intragastrically with rapamycin at a dose of 2.5 mg/kg per day for 5 weeks. Body weights and food intakes of the mice were recorded weekly. At the end of the study, blood samples were collected for glucose, lipid and insulin evaluations. Adipose tissues were weighed and lipid contents were monitored. Moreover, real-time PCR and Western blotting were applied to detect the expression levels of beige and brown fat marker genes in white adipose tissue (WAT) and brown adipose tissue (BAT). Our data demonstrated that Rap exposure significantly ameliorated metabolic defects including hyperglycaemia, dyslipidaemia and insulin resistance in the fatty mice. Furthermore, Rap treatment led to decreased tissue weights and lipid contents both in WAT and BAT. Remarkably, expression levels of BAT marker genes including uncoupling protein-1 (UCP-1), cell death-inducing DNA fragmentation factor-alpha-like effector A (CIDEA), PR-domain containing protein-16 (PRDM16) and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) were significantly down-regulated in Rap-treated fatty mice. This report demonstrates Rap exposure is capable of inhibiting adipose tissue browning in high-fat diet-induced fatty mice, and provides evidence for deeper understanding of Rap's influence on lipid homeostasis.


Assuntos
Tecido Adiposo Marrom/metabolismo , Tecido Adiposo/metabolismo , Antibacterianos/farmacologia , Sirolimo/farmacologia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Animais , Glicemia/análise , Peso Corporal/efeitos dos fármacos , Dieta Hiperlipídica , Regulação para Baixo/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Insulina/sangue , Lipídeos/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo
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