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1.
Talanta ; 271: 125655, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38237278

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are high-profile organic pollutants to be poisonous, carcinogenic, and mutagenic, and widely distributed at trace levels in the environment. In order to effectively enrich PAHs, two stable covalent organic frameworks (COFs, TAPT-OMe-PDA and TPB-DMTP) were prepared by combining 2,4,6-tri(4-aminophenyl)-1,3,5-triazine (TAPT) and 1,3,5-tri(4-aminophenyl) benzene (TAPB) with 2,5-dimethoxy-phenyl-1,4-diformaldehyde (OMe-PDA), respectively. Even though the surface area of TAPT-OMe-PDA was much lower than that of TPB-DMTP, it still demonstrated much better extraction efficiencies towards PAHs as the solid phase microextraction (SPME) coating. Therefore, the TAPT-OMe-PDA coated fiber was coupled with gas chromatography-mass spectrometry (GC-MS) to establish a practical and sensitive method, after the extraction parameters (extraction time, extraction temperature, desorption temperature, desorption time, salt concentration and pH) were optimized. This developed analytical method showed wide linear ranges, low limits of detection, good repeatability and reproducibility. Finally, five PAHs in three water samples were detected and quantified precisely (2.72-38.7 ng·L-1) with satisfactory recoveries (88.3%-118%).

2.
J Hazard Mater ; 466: 133541, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38286049

RESUMO

The size of the adsorbent has the potential to influence extraction performance, but the size effect at the nanoscale is still poorly understood. In this study, organic-inorganic hybrid nanospheres (OIHNs) with controllable nanoscale sizes of 30, 50, and 100 nm were successfully prepared. These materials were further fabricated as solid phase microextraction (SPME) coatings with similar thicknesses, and coupled with gas chromatography-mass spectrometry (GC-MS) to investigate their extraction performance. The results showed that the extraction capacities of OIHNs for chlorobenzenes (CBs) and polycyclic aromatic hydrocarbons (PAHs) were much better than those of their corresponding derived carbon materials, despite the smaller specific surface areas and lower porosities of them. In addition, the enrichment performance increased significantly with decreasing particle size, and the OIHN-30 coating demonstrated the best performance, with enrichment factors ranging from 1098 to 6853 for CBs. Finally, a highly sensitive and practical analytical method was established with a wide linear range of 0.5-5000 ng·L-1, and the limits of quantification (LOQs) were 0.43-1.7 ng·L-1. The determinations of ultratrace CBs in five marine water samples and five fresh water samples were realized successfully. This study is expected to contribute to a deep understanding of the environmental effects of nanoparticles and the design of high-performance adsorbents.

3.
Phytomedicine ; 123: 155188, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38056146

RESUMO

BACKGROUND: Non-alcoholic steatohepatitis (NASH) is a global health problem with no effective treatment. Isoquercitrin (IQ) alters hepatic lipid metabolism and inhibits adipocyte differentiation. The underlying regulatory mechanisms of IQ in regulating insulin resistance (IR) and lipid metabolism remain unclear. PURPOSE: This study was aimed at investigating the effects of IQ on NASH and deciphering whether the underlying mechanisms are via modulation of galectin-3 mediated IR and lipid metabolism. METHODS: IR-HepG2 cell lines were used to demonstrate the ability of IQ to modulate galectin-3-mediated glucose disposal and lipid metabolism. A 20-week high-fat diet (HFD)-induced NASH model was established in C57BL/6J mice, and the protective effect of IQ on lipid disposal in the liver was verified. Further, the mRNA and protein levels of glucose and lipid metabolism were investigated, and lysophosphatidylcholine (LPC) and acylcarnitine (AC) profiling were performed to characterize the changes in endogenous substances associated with mitochondrial function and lipid metabolism in serum and cells. Furthermore, the pharmacokinetic features of IQ were explored in a rat model of NASH. RESULTS: IQ restored liver function and ameliorated inflammation and lipid accumulationin NASH model mice. Notably, significant regulation of the proteins included fatty acid-generating and transporting, cholesterol metabolism enzymes, nuclear transcription factors, mitochondrial metabolism, and IR-related enzymes was noted to be responsible for the therapeutic mechanisms of IQ against experimental NASH. Serum lipid metabolism-related metabolomic assay confirmed that LPC and AC biosynthesis mostly accounted for the therapeutic effect of IQ in mice with NASH and that IQ maintained the homeostasis of LPC and AC levels. CONCLUSION: This is the first study showing that IQ protects against of NASH by modulating galectin-3-mediated IR and lipid metabolism. The mechanisms responsible for liver protection and improved lipid metabolic disorder by IQ may be related to the suppression of IR and regulation of mitochondrial function and lipid metabolism. Galectin-3 down-regulation represents a potentially novel approach for the treatment and prevention of NASH.


Assuntos
Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica , Quercetina/análogos & derivados , Camundongos , Animais , Ratos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Galectina 3/genética , Galectina 3/metabolismo , Galectina 3/farmacologia , Metabolismo dos Lipídeos , Camundongos Endogâmicos C57BL , Fígado , Dieta Hiperlipídica/efeitos adversos , Glucose/metabolismo , Lipídeos
4.
Org Lett ; 25(39): 7192-7197, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37733632

RESUMO

Sulfilimines, the aza analogues of sulfoxides, are of increasing interest in medicinal and agrochemical research programs. However, the development of efficient routes for their synthesis has remained relatively unexplored. In this study, we report a transition metal-free, selective S-arylation reaction between sulfenamides and arynes, enabling the facile preparation of structurally diverse sulfilimines under mild and redox-neutral conditions in good yields. The application value of our method was further demonstrated by scale-up synthesis, downstream derivatization, and robustness screen.

5.
Nat Commun ; 14(1): 1324, 2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-36898997

RESUMO

Newcastle disease virus (NDV) belongs to Paramyxoviridae, which contains lethal human and animal pathogens. NDV RNA genome is replicated and transcribed by a multifunctional 250 kDa RNA-dependent RNA polymerase (L protein). To date, high-resolution structure of NDV L protein complexed with P protein remains to be elucidated, limiting our understanding of the molecular mechanisms of Paramyxoviridae replication/transcription. Here, we used cryo-EM and enzymatic assays to investigate the structure-function relationship of L-P complex. We found that C-terminal of CD-MTase-CTD module of the atomic-resolution L-P complex conformationally rearranges, and the priming/intrusion loops are likely in RNA elongation conformations different from previous structures. The P protein adopts a unique tetrameric organization and interacts with L protein. Our findings indicate that NDV L-P complex represents elongation state distinct from previous structures. Our work greatly advances the understanding of Paramyxoviridae RNA synthesis, revealing how initiation/elongation alternates, providing clues for identifying therapeutic targets against Paramyxoviridae.


Assuntos
Vírus da Doença de Newcastle , Fosfoproteínas , Animais , Humanos , Vírus da Doença de Newcastle/genética , Paramyxoviridae , Fosfoproteínas/metabolismo , RNA , RNA Polimerase Dependente de RNA/metabolismo , Proteínas Virais/metabolismo
6.
J Clin Lab Anal ; 37(1): e24795, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36464783

RESUMO

BACKGROUND: Acquired immune deficiency syndrome (AIDS), human immunodeficiency virus (HIV) infection, and antiretroviral therapy are usually associated with metabolic disorders. Screening for biomarkers to evaluate the progression of metabolic disorders is important for the diagnosis and treatment of HIV infection. This study aimed to establish and validate a method to quantify serum aromatic amino acid (AAA) metabolites as biomarkers of metabolic disorders in patients with HIV. METHODS: The AAAs and metabolites were analyzed using high-performance liquid chromatography-tandem mass spectrometry. Pearson's correlation, heatmap, and receiver operating characteristic curve analyses were used for statistical analysis. RESULTS: Under optimal detection conditions, the lower limits of phenylalanine (Phe), tryptophan (Trp), kynurenine (Kyn), tyrosine, phenylacetylglutamine (PAGln), and 5-hydroxytryptamine quantification reached 0.02, 0.02, 0.01, 0.02, 0.01, and 0.002 µg/ml, respectively, and the precision of intra- and inter-day was stay below 10.30%. Serum samples were stable for at least 6 months when stored at -80°C. The inter-group differences and associations between the biomarkers exhibited a particular volatility trend in PAGln, Trp, and Kyn metabolism in HIV-infected patients with metabolic syndrome. CONCLUSIONS: The developed method can be used for rapid and sensitive quantification of the AAA metabolism profile in vivo to further appraise the process of HIV infection, evaluate intervening measures, conduct mechanistic investigations, and further study the utility of PAGln, a characteristic metabolite of AAA, as a biomarker of HIV infection coupled with metabolic syndrome.


Assuntos
Infecções por HIV , Síndrome Metabólica , Humanos , Aminoácidos Aromáticos , Espectrometria de Massas em Tandem/métodos , Triptofano , Biomarcadores
7.
Ann Transl Med ; 10(22): 1205, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36544639

RESUMO

Background: Proprotein convertase subtilisin/kexin type 9 (PCSK9) belongs to an intracellular invertase or decarboxylase and is an independent risk factor for atherosclerosis (AS). This study aimed to investigate the therapeutic potential of the PCSK9 inhibitor, inclisiran, and its underlying mechanism in AS. Methods: ApoE-/- mice were fed with a high-fat diet (HFD) and intraperitoneally injected with 1, 5, or 10 mg/kg inclisiran. Low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), triglyceride (TG), and high-density lipoprotein cholesterol (HDL-C) levels were determined using commercially available kits. Oil Red O staining was applied to detect the aortic plaque area and oil formation. Human umbilical vein endothelial cells (HUVECs) were treated with oxidized low-density lipoprotein (ox-LDL) to induce cell injuries. Cell death was determined using a Hoechst 33342/propidium iodide (PI) dual-staining assay. Cytotoxicity was measured by lactate dehydrogenase (LDH) activity analysis. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analyses were performed to examine the pyroptosis-related factors. Results: Inclisiran inhibited the levels of LDL-C, TC, and TG, but increased the HDL-C level in the AS animal model. It also significantly inhibited plaque and oil droplet formation in a dose-dependent manner. Moreover, inclisiran markedly inhibited pyroptosis, as evidenced by the decreased levels of cleaved-caspase-1, NOD-like receptor family pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein containing a caspase-1 recruitment domain (ASC), gasdermin-D (GSDMD)-N, interleukin (IL)-1ß, and IL-18. Furthermore, inclisiran substantially inhibited cell death and cytotoxicity induced by ox-LDL in HUVECs. Conclusions: Inclisiran exerted an anti-atherosclerotic effect by inhibiting pyroptosis. This study provides a theoretical basis for the therapeutic potential of inclisiran in AS.

8.
Front Pharmacol ; 13: 984611, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36059967

RESUMO

Objective: To explore the active components and epigenetic regulation mechanism underlying the anti-inflammatory effects of Lonicerae Japonicae Flos and Forsythiae Fructus herb-pair (LFP) in carbon tetrachloride (CCl4)-induced rat liver fibrosis. Methods: The main active ingredients and disease-related gene targets of LFP were determined using TCMSP and UniProt, and liver fibrosis disease targets were screened in the GeneCards database. A network was constructed with Cytoscape 3.8.0 and the STRING database, and potential protein functions were analyzed using bioinformatics analysis. Based on these analyses, we determined the main active ingredients of LFP and evaluated their effects in a CCl4-induced rat liver fibrosis model. Serum biochemical indices were measured using commercial kits, hepatocyte tissue damage and collagen deposition were evaluated by histopathological studies, and myofibroblast activation and inflammation were detected by reverse transcription-polymerase chain reaction (RT-PCR) and western blotting. High-performance liquid chromatography-mass spectrometry was performed to determine the levels of homocysteine, reduced glutathione, and oxidized glutathione, which are involved in inflammation and oxidative stress. Results: The main active components of LFP were quercetin, kaempferol, and luteolin, and its main targets were α-smooth muscle actin, cyclooxygenase-2, formyl-peptide receptor-2, prostaglandin-endoperoxide synthase 1, nuclear receptor coactivator-2, interleukinß, tumor necrosis factor α, CXC motif chemokine ligand 14, and transforming growth factor ß1. A combination of quercetin, kaempferol, and luteolin alleviated the symptoms of liver fibrosis. Conclusion: The results of this study support the role of LFP in the treatment of liver fibrosis, and reveal that LFP reduces collagen formation, inflammation, and oxidative stress. This study suggests a potential mechanism of action of LFP in the treatment of liver fibrosis.

9.
BMC Cancer ; 22(1): 855, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35931997

RESUMO

BACKGROUND: Colorectal cancer (CRC) is the third most common cancer worldwide. However, limited effective biomarkers are associated with the tumorigenesis and prognosis of CRC. METHODS: The present study identified potential signatures from The Cancer Genome Atlas (TCGA) database and further validated the identified biomarkers in CRC tissues by immunohistochemistry (IHC). RESULTS: The expression of insulin-like growth factor 1 receptor (IGF-1R) and Livin gene was significantly upregulated in CRC samples compared to the adjacent normal samples in the TCGA dataset. IHC indicated that IGF-1R and Livin protein levels are increased in CRC and adenoma tissues compared to normal tissues. Notably, the IGF-1R protein levels differed significantly between adenoma and CRC. The elevated IGF-1R and Livin expression was associated with CRC clinicopathological features, including age, gender, histological subtype, individual cancer stages, nodal metastasis, and TP53-mutant in TCGA. Additionally, the IGF-1R promoter methylation level was closely related to CRC. Consistent with the TCGA study, IHC indicated that overexpressed IGF-1R and Livin proteins were independent risk factors for stage and metastasis. A marked correlation was established between IGF-1R and Livin expression in CRC, while the survival map showed no significant correlation with CRC. Kaplan-Meier survival curves showed that CRC patients with high IGF-1R or Livin expression had a prolonged overall disease-free survival than those with low expression in TCGA. CONCLUSION: IGF-1R and Livin are associated with CRC tumorigenesis and might be valuable for novel biomarker identification and targeted therapeutic strategy development.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias Colorretais , Proteínas Inibidoras de Apoptose/metabolismo , Proteínas de Neoplasias/metabolismo , Receptor IGF Tipo 1/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/análise , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinogênese/patologia , Neoplasias Colorretais/patologia , Humanos , Imuno-Histoquímica , Proteínas Inibidoras de Apoptose/análise , Proteínas de Neoplasias/análise , Estadiamento de Neoplasias , Prognóstico , Receptor IGF Tipo 1/análise , Receptor IGF Tipo 1/genética
10.
Prog Mol Biol Transl Sci ; 189(1): 259-326, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35595351

RESUMO

Cancer represents a leading cause of death, despite the rapid progress of cancer research, leading to urgent need for accurate preclinical model to further study of tumor mechanism and accelerate translational applications. Cancer cell lines cannot fully recapitulate tumors of different patients due to the lack of tumor complexity and specification, while the high technical difficulty, long time, and substantial cost of patient-derived xenograft model makes it unable to be used extensively for all types of tumors and large-scale drug screening. Patient-derived organoids can be established rapidly with a high success rate from many tumors, and precisely replicate the key histopathological, genetic, and phenotypic features, as well as therapeutic response of patient tumor. Therefore, they are extensively used in cancer basic research, biobanking, disease modeling and precision medicine. The combinations of cancer organoids with other advanced technologies, such as 3D bio-printing, organ-on-a-chip, and CRISPR-Cas9, contributes to the more complete replication of complex tumor microenvironment and tumorigenesis. In this review, we discuss the various methods of the establishment and the application of patient-derived organoids in diverse tumors as well as the limitations and future prospects of these models. Further advances of tumor organoids are expected to bridge the huge gap between bench and bedside and provide the unprecedented opportunities to advance cancer research.


Assuntos
Neoplasias , Organoides , Bancos de Espécimes Biológicos , Humanos , Neoplasias/patologia , Organoides/patologia , Medicina de Precisão/métodos , Microambiente Tumoral
11.
RSC Adv ; 12(10): 6265-6278, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35424572

RESUMO

Decontamination and reuse of greywater in rural areas has attracted increasing attention. Typical contaminants in grey water are SDBS, which has a stubborn molecular structure. In this study, Fe2O3-coated volcanic rocks (Fe2O3-VR) prepared from FeCl3 solution by a heating evaporation method can reach 95% removal of SDBS, which is 80% higher than before. The effect of contact time, pH, initial concentration, FeCl3 solution concentration, adsorbent dosage and calcination temperature on the removal rate was researched and modeled by response methodology (RSM) and artificial neural network (ANN). Based on the univariate test, the Box-Behnken design method was used to establish the data sample, which represented a quadratic polynomial model with p-value <0.001, R 2 = 0.9872, while the ANN model has the better performance with R 2 = 0.9961. The weights of the BP-ANN model were further analyzed using the Garson equation, and the results showed that the validity ranking of the variables was as follows: contact time (37.31%) > calcination temperature (29.43%) > dosage (24.44%) > initial concentration (17.18%) > FeCl3 solution concentration (17.18%) > pH (11.56%). Genetic algorithm (GA) and particle swarm optimization (PSO) were selected to optimize the process parameters. The results showed that ANN-PSO methodology presented a satisfactory alternative and the predicted removal efficiency was 99.9982% with relative error = 0.2230. The optimum level of contact time, pH, initial SDBS concentration, FeCl3 solution concentration, adsorbent dosage and calcination temperature is 136.45 min, 5.64, 22.4 mg L-1, 0.3 mol L-1, 83.21 g L-1, 274.02 °C, respectively. Moreover, Fe2O3-VR was characterized via instrumental analyses (SEM-EDS, FTIR, XRD, BET).

13.
Nanomaterials (Basel) ; 12(4)2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35214908

RESUMO

An economical corncob biochar-based magnetic iron-copper bimetallic nanomaterial (marked as MBC) was successfully synthesized and optimized through a co-precipitation and pyrolysis method. It was successfully used to activate H2O2 to remove ciprofloxacin (CIP) from aqueous solutions. This material had high catalytic activity and structural stability. Additionally, it had good magnetic properties, which can be easily separated from solutions. In MBC/H2O2, the removal efficiency of CIP was 93.6% within 360 min at optimal reaction conditions. The conversion of total organic carbon (TOC) reached 51.0% under the same situation. The desorption experiments concluded that adsorption and catalytic oxidation accounted for 34% and 66% on the removal efficiency of CIP, respectively. The influences of several reaction parameters were systematically evaluated on the catalytic activity of MBC. OH was proved to play a significant role in the removal of CIP through electron paramagnetic resonance (EPR) analysis and a free radical quenching experiment. Additionally, such outstanding removal efficiency can be attributed to the excellent electronic conductivity of MBC, as well as the redox cycle reaction between iron and copper ions, which achieved the continuous generation of hydroxyl radicals. Integrating HPLC-MS, ion chromatography and density functional theory (DFT) calculation results, and possible degradation of the pathways of the removal of CIP were also thoroughly discussed. These results provided a theoretical basis and technical support for the removal of CIP in water.

14.
Front Pharmacol ; 13: 1116257, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36699093

RESUMO

Objective: To explore the pharmacological effects and molecular mechanism of quercetin 7-rhamnoside (Q7R) in the treatment of cholestatic hepatitis induced by alpha-naphthylisothiocyanate (ANIT). Methods: ANIT-induced cholestatic hepatitis rat model was used to investigate the hepatoprotective effects of three different doses of Q7R (1.25 mg/kg; 2.5 mg/kg; 5 mg/kg). Serum biochemical indices were detected using commercial kits. H&E and masson staining were used to observe hepatic tissue damage and collagen deposition in hepatocytes. The metabolism of bile acid-related substances was detected via HPLC-MS/MS by 5-(diisopropylamino) amylamine (DIAAA) derivative method. Hepatocyte injury, cholestasis, and inflammation were detected at the mRNA and protein levels using reverse transcription-polymerase chain reaction (RT-PCR) and western blotting, respectively. Results: Q7R can decrease the level of CYP7A1, and increase FXR, CYP27A1 so then improving abnormal bile acid secretion. Furthermore, Q7R can also ameliorating inflammation by reduce TNF-α, IL-1ß, PTGS1, PTGS2, NCOA2, NF-κB level. Therefore, Q7R had an effective therapeutic effect on ANIT-induced cholestatic hepatitis, improving abnormal bile acid secretion, and inhibiting inflammatory responses. Conclusion: The results demonstrated that Q7R treat cholestatic hepatitis by regulating bile acid secretion and alleviating inflammation.

15.
Sci Rep ; 11(1): 15596, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34341423

RESUMO

Dihydroquercetin (DHQ), an extremely low content compound (less than 3%) in plants, is an important component of dietary supplements and used as functional food for its antioxidant activity. Moreover, as downstream metabolites of DHQ, an extremely high content of dihydromyricetin (DHM) is up to 38.5% in Ampelopsis grossedentata. However, the mechanisms involved in the biosynthesis and regulation from DHQ to DHM in A. grossedentata remain unclear. In this study, a comparative transcriptome analysis of A. grossedentata containing extreme amounts of DHM was performed on the Illumina HiSeq 2000 sequencing platform. A total of 167,415,597 high-quality clean reads were obtained and assembled into 100,584 unigenes having an N50 value of 1489. Among these contigs, 57,016 (56.68%) were successfully annotated in seven public protein databases. From the differentially expressed gene (DEG) analysis, 926 DEGs were identified between the B group (low DHM: 210.31 mg/g) and D group (high DHM: 359.12 mg/g) libraries, including 446 up-regulated genes and 480 down-regulated genes (B vs. D). Flavonoids (DHQ, DHM)-related DEGs of ten structural enzyme genes, three myeloblastosis transcription factors (MYB TFs), one basic helix-loop-helix (bHLH) TF, and one WD40 domain-containing protein were obtained. The enzyme genes comprised three PALs, two CLs, two CHSs, one F3'H, one F3'5'H (directly converts DHQ to DHM), and one ANS. The expression profiles of randomly selected genes were consistent with the RNA-seq results. Our findings thus provide comprehensive gene expression resources for revealing the molecular mechanism from DHQ to DHM in A. grossedentata. Importantly, this work will spur further genetic studies about A. grossedentata and may eventually lead to genetic improvements of the DHQ content in this plant.


Assuntos
Ampelopsis/genética , Vias Biossintéticas/genética , Flavonóis/biossíntese , Genes de Plantas , Quercetina/análogos & derivados , Análise por Conglomerados , Flavonoides/biossíntese , Flavonoides/química , Flavonoides/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Anotação de Sequência Molecular , Quercetina/biossíntese , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcriptoma/genética
16.
Waste Manag ; 130: 127-135, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34082398

RESUMO

In this study, the effect of leachate seepage on the strength properties of a landfill temporary cover material: sewage sludge solidified with soda residue, ground granulated blast furnace slag, and quicklime, was investigated using small-scale column tests. The strength of the solidified sludge was reflected by penetration resistance with a micro penetrometer. The results showed that the penetration resistance increased at first, but then decreased with the increase in duration. The peak value for penetration resistance appeared at around the 75th day under the effect of leachate seepage. In contrast, without leachate seepage, penetration resistance increased at first as duration increased and then remained stable. The main hydration products were calcium silicate hydrate, ettringite and hydrocalumite. Some pollutants, such as copper, chromium, and arsenic, were also stabilized by the solidified sludge. The nuclear magnetic resonance results showed that the sample with highest penetration resistance had a reduced pore volume, especially macropore volume. Furthermore, leachate corrosion and the removal of some substances contributed to the decrease in penetration resistance after long-term seepage. The strength performance of temporary cover in laboratory short-term seepage and leachate soaking environments might be different from that in a landfill leachate seepage environment. This study improves understanding about the performance of temporary cover materials in landfill.


Assuntos
Arsênio , Poluentes Químicos da Água , Cromo , Esgotos , Instalações de Eliminação de Resíduos
17.
Am J Pharm Educ ; 83(6): 7030, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31507293

RESUMO

Objective. To assess the impact of forming student learning teams based on problem solving styles on team performance and student perceptions of team quality. Methods. This was a prospective observational study involving students in the first year of a Doctor of Pharmacy degree program. Collaborative learning teams (balanced, implementer, optimizer, and random assignment) were created based on students' results on the Basadur Creative Problem Solving Profile Inventory. The teams remained in place across all courses for the first academic year, and those courses that incorporated team-based learning (TBL) were included in the study. Team performance was assessed by administering team readiness assurance tests. The quality of team interactions was assessed using the team satisfaction domain in the Comprehensive Assessment of Team Member Effectiveness (CATME) Smarter Teamwork system and the Team Performance Scale. Results. Each of the 237 first-year pharmacy students enrolled was assigned to one of 41 teams. All teams participated in the study. A significant difference in team performance was observed in the Principles of Patient Centered Care course but not in any of the other courses. No significant differences were found in quality of team interactions. Conclusion. Neither team performance, nor team satisfaction, nor quality of team interactions was impacted by the method of team formation that was used. Given the existing evidence and the results of this study, team formation process, regardless of method used, may have negligible influence on the performance of collaborative learning teams in courses taught using TBL.


Assuntos
Educação em Farmácia/métodos , Aprendizagem Baseada em Problemas/métodos , Currículo , Avaliação Educacional/métodos , Processos Grupais , Humanos , Aprendizagem , Resolução de Problemas , Estudos Prospectivos , Estudantes de Farmácia
18.
J Vet Med Educ ; 46(3): 372-378, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30721108

RESUMO

Practice-based clerkships provide a way for students to experience the types of cases, clients, and procedures that they can expect to see in a general practice setting. These clerkships are typically quite different from those offered in teaching hospitals. Forty-seven (65.28%) of the 72 invited veterinary medicine students from three cohorts participated in pre- and post-test surveys designed to compare their expectations to their actual experiences. Students reported significant positive changes in terms of adequate supervision, approachability of practitioner, and comfort level when asking questions, as well as seeing different cases than they see at the teaching hospital. Students reported significant negative changes in terms of their ability to interact with clients as much as they expected with respect to the practice of communication skills, history-taking skills, preventative therapy discussions with clients, and treatment. These findings were supported by written survey comments regarding the most and least helpful portions of the clerkship. We suggest further research to study student experiences over time and to survey practitioners before and following placement with veterinary students; the aim would be to obtain more information about the expectations and success of practice-based clerkships.


Assuntos
Estágio Clínico , Educação em Veterinária , Estudantes de Medicina , Animais , Competência Clínica , Currículo , Humanos , Estudantes de Medicina/psicologia , Inquéritos e Questionários
19.
Mentor Tutoring ; 27(1): 109-125, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32982567

RESUMO

The purpose of our study was to assess how an academic health center (AHC) mentor academy program affected mentor competence and optimized mentor-mentee relationship. Mixed methods were used to assess the effectiveness of an AHC mentor program at a clinical translational science institute (CTSI). Twenty biomedical research faculty mentors took a validated survey and submitted reflective writings to discover if they corroborated or refuted statistically significant survey results. There was significant improvement in participants' confidence of mentor skills, integral mentoring quality and the extent to which they fulfill mentees' expectations. Males provided constructive feedback and helped mentees develop goal strategies more often compared to females. Reflective writings supported these findings yet refuted two survey findings. The use of a mixed methods approach offers novel insight into how mentoring programs benefit translational research mentoring capacity building and raises questions about the sole use of surveys as evidence of program effectiveness.

20.
Curr Probl Cancer ; 43(1): 18-26, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29776595

RESUMO

AIM: Leukocyte-associated immunoglobulin-like receptor-1 (LAIR-1) is an immune inhibitory receptor which is expressed within most types of hematopoietic cells and negatively regulates immune responses. Recently, we found LAIR-1 expression to be present within tumors of nonhematopoietic lineages. However, the roles of LAIR-1 in hepatocellular carcinoma (HCC) have yet to be examined. The purpose of this study was to investigate the expression of LAIR-1 in HCC tissue and assess its clinical significance at this site. MATERIALS AND METHODS: Expression levels of LAIR-1 within HCC samples collected from 90 patients and compared with that of slides of normal liver tissue collected from 9 non-HCC patients were measured by immunohistochemistry using tissue microarrays. A semiquantitative score was assigned, as was based on staining intensity and percent of positive cells and a Spearman Rank correlation test was used to assess any potential significant correlations between LAIR-1 expression and clinicopathological factors. Overall survival analysis was performed using the Kaplan-Meier and Log Rank statistical test. RESULTS: LAIR-1 expression was detected in cancer tissue and adjacent tumor tissue, but not in normal liver tissue. The percent of LAIR-1-positive expression in cancer tissue of HCC samples was 97.78% (88/90) while that in adjacent tumor tissue was 96.67% (87/90). Significantly greater expression levels of LAIR-1 were obtained from cancer tissue (Mean ±â€¯SD = 5.722 ±â€¯2.145) than that in adjacent tumor tissue (4.141 ±â€¯1.486). In addition, LAIR-1 expression was found to be significantly correlated with pathological grade of HCC, T stage, and age. Expression levels of LAIR-1 were related with worse overall survival rates of HCC patients, especially in HCC patients with hepatic cirrhosis. CONCLUSION: Results of this study show that LAIR-1 is expressed in HCC tissues and that high levels of LAIR-1 expression are associated with the poor cancer differentiation. In addition, overexpression of LAIR-1 was significantly associated with worse overall survival in the patients with HCC. These data suggest that LAIR-1 may be an independent predictor for clinical outcomes in patients with HCC.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/secundário , Neoplasias Hepáticas/patologia , Receptores Imunológicos/metabolismo , Adolescente , Adulto , Idoso , Carcinoma Hepatocelular/metabolismo , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Neoplasias Hepáticas/metabolismo , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
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