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Here we report the palladium-catalyzed ß-C(sp3)-H nitrooxylation of aliphatic carboxamides using a modified quinoline auxiliary. Notably, Al(NO3)3·9H2O was used as a nitrate source as well as a practical oxidant. The 5-chloro-8-aminoquinoline auxiliary was nitrated in situ during the reaction, which may enhance its directing ability and help its removal. The reaction has a broad substrate scope with a variety of aliphatic carboxamides. The multiple substituted auxiliary can be easily removed and recovered. Two C-H-insertion palladacycle intermediates were isolated and characterized to elucidate the mechanism.
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OBJECTIVE: Endoscopic surgery is an effective technique for preserving the nipple and areola, as well as for sentinel lymph node biopsy and breast implant reconstruction. However, the technical challenges associated with endoscopic surgery have limited its widespread adoption. METHODS: In the normal single-port endoscopic surgery, the ultrasonic knife was accessed through the retractor. In our modified procedure, a tiny 5 mm incision was made at the lateral margin underneath the breast, serving as the second entry port for the ultrasonic scalpel, which was referred to as the "Haigui-1 hole". Preoperative and postoperative indicators such as blood loss, operative time, and postoperative drainage volume were collected. Differences between parameters were compared using Student's t test. RESULTS: Endoscopic surgery with the assistance of the "Haigui-1 hole" led to preserved breast aesthetics with minimal scarring. Moreover, "Haigui-1 hole" surgery significantly reduced the operation time, intraoperative bleeding, and postoperative drainage volume compared to normal single-port endoscopic surgery. CONCLUSION: The "Haigui-1 hole" procedure, which involves the addition of a second entrance to improve the maneuverability of the ultrasonic knife, is worthy of further promotion.
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Neoplasias da Mama , Endoscopia , Humanos , Feminino , Neoplasias da Mama/cirurgia , Endoscopia/métodos , Pessoa de Meia-Idade , Adulto , Duração da CirurgiaRESUMO
Achieving the complete mineralization of persistent pollutants in wastewater is still a big challenge. Here, we propose an efficient photo-self-Fenton reaction for the degradation of different pollutants using the high-density (Ag: 22â wt %) of atomically dispersed AgCo dual sites embedded in graphic carbon nitride (AgCo-CN). Comprehensive experimental measurements and density functional theory (DFT) calculations demonstrate that the Ag and Co dual sites in AgCo-CN play a critical role in accelerating the photoinduced charge separation and forming the self-Fenton redox centers, respectively. The bimetallic AgCo-CN exhibited excellent photocatalytic performance toward the phenol even under extreme conditions due to an efficient degradation pathway and in situ generation of the hydrogen peroxide producing the main active oxygen species (â OH and 1 O2 ) and showed long-term activity in a self-design photo-Filter reactor for the purification of the phenol. Our discoveries pave the way for the design of efficient single-atoms photocatalysts-based photo-self-Fenton reaction for recalcitrant pollutant treatment.
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Designing the morphotropic phase boundary (MPB) has been the most sought-after approach to achieve high piezoelectric performance of piezoelectric materials. However, MPB has not yet been found in the polarized organic piezoelectric materials. Here, we discover MPB with biphasic competition of ß and 3/1-helical phases in the polarized piezoelectric polymer alloys (PVTC-PVT) and demonstrate a mechanism to induce MPB using the compositionally tailored intermolecular interaction. Consequently, PVTC-PVT exhibits a giant quasistatic piezoelectric coefficient of >32 pC/N while maintaining a low Young's modulus of 182 MPa, with a record-high figure of merit of piezoelectricity modulus of about 176 pC/(N·GPa) among all piezoelectric materials.
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Ligas , Polímeros , Módulo de ElasticidadeRESUMO
Two Mo-Ti-mixed oxide clusters, Ti6Mo4 and Ti4Mo4, which contain the {Mo2V} unit commonly observed in many polyoxomolybdates, were successfully synthesized. The introduction of a {Mo2V} dopant into a titanium-oxide cluster (TOC) results in a red shift of the absorption edge, hence leading to a substantial enhancement of visible-light absorption. The band gap electron transition mainly involves the ligand-to-metal charge transfer (LMCT, benzoate-to-Mo) and MoV d-d transition. Both clusters show favorable visible-light responsiveness and charge-separation efficiency. Both serve as heterogeneous photocatalysts and exhibit excellent catalytic activity in CO2/epoxide cycloadditions under very mild conditions. The mechanism study suggests that the catalytically active sites are mainly MoV, and the photogenerated electrons and holes are both involved. Ti6Mo4 exhibits better photocatalytic activity than Ti4Mo4, demonstrating the crucial role of the titanium-oxide core, which corresponds to improved light absorption and charge-separation efficiency. Our findings highlight the potential of the {Mo2V} unit in constructing Mo-Ti-mixed oxide clusters with interesting topologies and excellent solar-light-harvesting activity.
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Five cluster polymers based on heterometal-doped titanium-oxide cluster (TOC) monomers are reported. The monomers feature Ti10-oxide cluster cores and are connected to the divalent closed-shell heterometal anchors by salicylate ligands. The Sr2+, Ba2+, and Pb2+ dopants cause the monomers to bind head-to-head and generate linear chains, while the Ca2+ and Cd2+ lead to head-to-tail connections and zigzag chains. The cluster polymers are responsive to visible-light up to 565 nm and photo-catalytically active in both H2 evolution and CO2/epoxide cycloaddition reactions. The photo-absorption, photo-charge separation, and photocatalytic properties of the cluster polymers are dependent on the heterometal dopants in order Cd > Pb > Ba > Sr > Ca. Heterometals serve as the catalytic sites in the cluster polymers, which depending on the contribution of the pCB bottom, facilitate photo-charge separation and interfacial charge transfer, further enhancing catalytic activity. The tunable compositions and topologies of the cluster polymers shown herein may inspire the design and synthesis of more multidimensional functional metal-oxide cluster materials for a variety of applications in the future.
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Framed through family life course theory, two studies were conducted to examine the relationship between parenting and Chinese emerging adults' conceptions of adulthood. Study 1 identified five important adult criteria among 763 participants (Mage = 23.13; 54.8% girls) through exploratory factor analysis. In Study 2, 616 participants (Mage = 22.51; 71.6% girls) completed measures of parental autonomy support (PAS) and psychological control (PPC), subjective adult status, and adult criteria. Results showed that PAS was positively associated with subjective adult status and endorsement of almost all adult criteria, whereas PPC was both positively and negatively associated with different adult criteria. Findings reveal the influence of family factors on youth transition to adulthood in the Chinese context and may have implications for family based interventions.
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Relações Pais-Filho , Poder Familiar , Feminino , Adolescente , Humanos , Adulto , Adulto Jovem , Masculino , Poder Familiar/psicologia , Análise Fatorial , Pais/psicologiaRESUMO
Nerves are emerging promoters of cancer progression, but the innervation of esophageal cancer and its clinicopathologic significance remain unclear. In this study, nerves were analyzed by immunohistochemistry in a cohort of 260 esophageal cancers, including 40 matched lymph node metastases and 137 normal adjacent esophageal tissues. Nerves were detected in 38% of esophageal cancers and were more associated with squamous cell carcinomas (P = 0.04). The surrounding or invasion of nerves by cancer cells (perineural invasion) was detected in 12% of esophageal cancers and was associated with reduced survival (P = 0.04). Nerves were found to express the following receptors for nerve growth factor (NGF): neurotrophic receptor tyrosine kinase 1 and nerve growth factor receptor. An association was suggested between high production of NGF by cancer cells and the presence of nerves (P = 0.02). In vitro, NGF production in esophageal cancer cells was shown by Western blot, and esophageal cancer cells were able to induce neurite outgrowth in the PC12 neuronal cells. The neurotrophic activity of esophageal cancer cells was inhibited by anti-NGF blocking antibodies. Together, these data suggest that innervation is a feature in esophageal cancers that may be driven by cancer cell-released NGF.
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Neoplasias Esofágicas/patologia , Invasividade Neoplásica/patologia , Fator de Crescimento Neural/metabolismo , Nervos Periféricos/patologia , Adulto , Idoso , Neoplasias Esofágicas/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Microambiente TumoralRESUMO
Pancreatic cancer has a dismal prognosis, and there is no targeted therapy against this malignancy. The neuronal membrane protein sortilin is emerging as a regulator of cancer cell development, but its expression and impact in pancreatic cancer are unknown. This study found that sortilin expression was higher in pancreatic cell lines versus normal pancreatic ductal epithelial cells, as shown by Western blot analysis and mass spectrometry. The increased sortilin level in pancreatic cancer cells was confirmed by immunohistochemistry in a series of 99 human pancreatic adenocarcinomas versus 48 normal pancreatic tissues (P = 0.0014). Sortilin inhibition by siRNA and the pharmacologic inhibitor AF38469 strongly reduced the adhesion and invasion of pancreatic cancer cells without affecting cell survival and viability. Sortilin inhibition also decreased the phosphorylation of the focal adhesion kinase in Tyr925. Together, these data show that sortilin contributes to pancreatic cancer invasion and could eventually be targeted in therapy.
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Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Neoplasias Pancreáticas/patologia , Adesão Celular/fisiologia , Movimento Celular/fisiologia , Humanos , Invasividade Neoplásica/patologia , Neoplasias Pancreáticas/metabolismo , Neoplasias PancreáticasRESUMO
The first isolable silylene-germylene complexâ 5 was assembled by a salt metathesis reaction between the germylene anionâ 3 and the N-heterocyclic chlorosilyleneâ 4, and structurally characterized. The central structure of 5 demonstrates a remarkable gauche-bent geometry with the silylene and germylene units, which are interconnected by a Si-Ge bond with a length of 2.4498(9)â Å. This value is not only perceptibly longer than the distances known in doubly bonded germasilenes, and also slightly longer than those in germylsilanes. The DFT calculations on 5 confirmed a nearly nonpolar SiI -GeI single-bond nature and its bonding orbital, as well as the aromaticity of the C3 NGe-rings in 3 and 5. The latter increases the molecular stability of 3 and 5, and makes the preparation of silylene-germylene complexâ 5 a reality.
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PURPOSE: Laryngopharyngeal reflux (LPR) accounts for 4-10% of outpatient visits. The standard domestic LPR diagnostic tools are the reflux finding score (RFS) and reflux symptom index (RSI). Narrow band imaging (NBI) can identify previously unknown characteristic microvessel features. Our aim was to explore the role of NBI in LPR diagnosis. MATERIALS AND METHODS: We recruited 56 LPR outpatients and 41 symptom-negative controls. All individuals received RSI and RFS scores and underwent 24-hour multichannel intraluminal impedance-PH (MII-pH) monitoring and endoscopic NBI before and after treatment. The positivity rates in the study and control groups, before and after treatment, and using NBI and the conventional method were evaluated. RESULTS: Fifty-one LPR and six control patients had sparse light brownish dots or tufted light brownish dots in the postcricoid region. The RSI and RFS positivity rates were 31.3% and 87.1%, respectively. NBI is as effective as the RFS (P < 0.05), and has poor consistency with the RSI (P < 0.05). Fifty-three LPR patients underwent posttreatment laryngoscopy. The positivity rate decreased to 17.0% (P < 0.05). CONCLUSION: NBI has good value for LPR diagnosis.
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Refluxo Laringofaríngeo/diagnóstico , Imagem de Banda Estreita , Adulto , Monitoramento do pH Esofágico , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Natamycin is often added to pastries, cheeses, and beverages. The residual amount of natamycin should be less than 10 mg kg-1 . The current method for its determination in various foodstuffs is high-performance liquid chromatography (HPLC). Capillary electrophoresis (CE) is a simple, fast, and environmentally friendly method with low reagent consumption and comparable separation performance. However, no reports were found on the determination of natamycin in foods by CE. A CE method to determine natamycin is therefore sought. RESULTS: Natamycin in foods was determined by the capillary zone electrophoresis (CZE) method with ultraviolet-visible (UV) detection. Separation conditions were optimized as 20 mM Na2 HPO4 , pH 9.2, with 25 kV applied voltage, and UV detection at 306 nm. Under optimal conditions, electrophoretic analysis was completed in less than 4 min, with a limit of detection (LOD) of 0.065 µg mL-1 and limit of quantitation (LOQ) of 0.22 µg mL-1 . A good linear relationship (r2 = 0.999) was obtained at the range of 0.1-25 µg mL-1 . A comparison with the HPLC-UV method was also carried out according to the National Standards of the People's Republic of China. CONCLUSION: The results obtained by the CZE and HPLC methods are comparable but the proposed CZE method can help us obtain a shorter detection time at low cost. © 2019 Society of Chemical Industry.
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Bebidas/análise , Queijo/análise , Cromatografia Líquida de Alta Pressão/métodos , Eletroforese Capilar/métodos , Conservantes de Alimentos/análise , Natamicina/análise , China , Limite de DetecçãoRESUMO
FAM3B, also known as PANcreatic DERived factor (PANDER), promotes gluconeogenesis and lipogenesis in hepatocytes. However, the underlying mechanism(s) still remains largely unclear. This study determined the mechanism of PANDER-induced FOXO1 activation in hepatocytes. In mouse livers and cultured hepatocytes, PANDER protein is located in both the cytoplasm and nucleus. Nuclear PANDER distribution was increased in the livers of obese mice. In cultured mouse and human hepatocytes, PANDER was co-localized with FOXO1 in the nucleus. PANDER directly interacted with FOXO1 in mouse and human hepatocytes. PANDER overexpression enhanced PANDER-FOXO1 interaction, and detained FOXO1 in the nucleus upon insulin stimulation in hepatocytes. With the increase in PANDER-FOXO1 interaction, PANDER overexpression upregulated the expression of gluconeogenic genes and promoted gluconeogenesis in both human and mouse hepatocytes. Luciferase reporter assays further revealed that PANDER augmented the transcriptional activity of FOXO1 on gluconeogenic genes. Moreover, PANDER overexpression also interfered the binding of AS1842856, a specific FOXO1 inhibitor, with FOXO1, and impaired its inhibitory effects on gluconeogenic gene expression and gluconeogenesis in hepatocytes. siRNA mediated-silencing of FOXO1 inhibited PANDER-promoted gluconeogenic gene expression and glucose production in hepatocytes. In conclusion, PANDER protein is abundantly present in the nucleus, where it functions as a new co-activator of FOXO1 to induce gluconeogenic gene expression in hepatocytes.
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Citocinas/metabolismo , Proteína Forkhead Box O1/metabolismo , Gluconeogênese , Glucose/metabolismo , Hepatócitos/metabolismo , Proteínas de Neoplasias/metabolismo , Animais , Células Cultivadas , Citocinas/genética , Proteína Forkhead Box O1/genética , Regulação da Expressão Gênica , Hepatócitos/citologia , Humanos , Resistência à Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Proteínas de Neoplasias/genéticaRESUMO
A sensitive method of CZE-ultraviolet (UV) detection based on the on-line preconcentration strategy of field-amplified sample injection (FASI) was developed for the simultaneous determination of five kinds of chlorophenols (CPs) namely 4-chlorophenol (4-CP), 2-chlorophenol (2-CP), 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP), and 2,6-dichlorophenol (2,6-DCP) in water samples. Several parameters affecting CZE and FASI conditions were systematically investigated. Under the optimal conditions, sensitivity enhancement factors for 4-CP, 2-CP, 2,4-DCP, 2,4,6-TCP, and 2,6-DCP were 9, 27, 35, 43, and 43 folds, respectively, compared with the direct CZE, and the baseline separation was achieved within 5 min. Then, the developed FASI-CZE-UV method was applied to tap and lake water samples for the five CPs determination. The LODs (S/N = 3) were 0.0018-0.019 µg/mL and 0.0089-0.029 µg/mL in tap water and lake water, respectively. The values of LOQs in tap water (0.006-0.0074 µg/mL) were much lower than the maximum permissible concentrations of 2,4,6-TCP, 2,4-DCP, and 2-CP in drinking water stipulated by World Health Organization (WHO) namely 0.3, 0.04, and 0.01 µg/mL, respectively, and thereby the method was suitable to detect the CPs according to WHO guidelines. Furthermore, the method attained high recoveries in the range of 83.0-119.0% at three spiking levels of five CPs in the two types of water samples, with relative standard deviations of 0.37-8.58%. The developed method was proved to be a simple, sensitive, highly automated, and efficient alternative to CPs determination in real water samples.
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Clorofenóis/análise , Eletroforese Capilar , Água Potável/química , Eletroforese Capilar/métodos , Limite de Detecção , Poluentes Químicos da Água/análiseRESUMO
Offline dispersive liquid-liquid microextraction combined with online pressure-assisted electrokinetic injection was developed to simultaneously enrich seven phenolic compounds in water samples, followed by determination using capillary electrophoresis, namely phenol, 4-chlorophenol, pentachlorophenol, 2,4,6-trichlorophenol, 2,4-dichlorophenol, 2-chlorophenol, and 2,6-dichlorophenol. Several parameters affecting separation performance of capillary electrophoresis and the enrichment efficiency of pressure-assisted electrokinetic injection and dispersive liquid-liquid microextraction were systematically investigated. Under the optimal conditions, seven phenolic compounds were completely separated within 14 min and good enrichment factors were obtained of 61, 236, 3705, 3288, 920, 86, and 1807 for phenol, 4-chlorophenol, pentachlorophenol, 2,4,6-trichlorophenol, 2,4-dichlorophenol, 2-chlorophenol, and 2,6-dichlorophenol, respectively. Good linearity was attained in the range of 0.1-200 µg/L for 2,4-dichlorophenol, 0.5-200 µg/L for 4-chlorophenol, pentachlorophenol, 2,4,6-trichlorophenol, 2-chlorophenol, and 2,6-dichlorophenol, as well as 1-200 µg/L for phenol, with correlation coefficients (r) over 0.9905. The limits of detection and quantification ranging from 0.03-0.28 and 0.07-0.94 µg/L were attained. This two step enrichment method was potentially applicable for the rapid and simultaneous determination of phenolic compounds in water samples.
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Cromatografia Capilar Eletrocinética Micelar , Microextração em Fase Líquida , Fenóis/análise , Poluentes Químicos da Água/análise , Eletroforese Capilar , PressãoRESUMO
Platinum-based doublet chemotherapy with or without bevacizumab is the standard treatment for untreated advanced nonsquamous non-small-cell lung cancer (NS-NSCLC). However, adding bevacizumab to chemotherapies other than paclitaxel-carboplatin is, though widely applied clinically, largely unjustified due to the lack of head-to-head data. We performed a Bayesian network meta-analysis (NMA) to address this important issue. Data of 8,548 patients from 18 randomized controlled trials (RCTs) receiving six treatments, including taxane-platinum (Taxane-Pt), gemcitabine-platinum (Gem-Pt), pemetrexed-platinum (Pem-Pt), taxane-platinum + bevacizumab (Taxane-Pt + B), gemcitabine-platinum + bevacizumab (Gem-Pt + B) and pemetrexed-platinum + bevacizumab (Pem-Pt + B), were incorporated into the analyses. Direct and indirect evidence of overall survival (OS) and progression-free survival (PFS) were synthesized at the hazard ratio (HR) scale and evidence of objective response rate (ORR) and serious adverse events (SAE) were synthesized at the odds ratio (OR) scale. Taxane-Pt + B showed significant advantages in OS (HR = 0.79, p < 0.001), PFS (HR = 0.54, p < 0.001) and ORR (OR = 2.7, p < 0.001) over Taxane-Pt with comparable tolerability (OR = 3.1, p = 0.08). Gem-Pt + B showed no OS benefit compared to any other treatment. No significant differences were detected between Pem-Pt + B and Pem-Pt in four outcomes. In terms of the benefit-risk ratio, Pem-Pt and Taxane-Pt + B were ranked the first and second, respectively. In conclusion, in the first-line treatment for advanced NS-NSCLC, Taxane-Pt and Gem-Pt are the most and least preferable regimens to be used with bevacizumab, respectively. Adding bevacizumab to Pem-Pt remains unjustified because it fails to improve efficacy or tolerability. In terms of the benefit-risk ratio, Pem-Pt and Taxane-Pt + B are the best and second-best treatment for this population.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Compostos Organoplatínicos/uso terapêutico , Intervalo Livre de Doença , Humanos , Metanálise em Rede , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
BACKGROUND: The current antiemetic prophylaxis for patients treated with highly emetogenic chemotherapy (HEC) included the olanzapine-based triplet and neurokinin-1 receptor antagonists (NK-1RAs)-based triplet. However, which one shows better antiemetic effect remained unclear. MATERIALS AND METHODS: We systematically reviewed 43 trials, involving 16,609 patients with HEC, which compared the following antiemetics at therapeutic dose range for the treatment of chemotherapy-induced nausea and vomiting: olanzapine, aprepitant, casopitant, fosaprepitant, netupitant, and rolapitant. The main outcomes were the proportion of patients who achieved no nausea, complete response (CR), and drug-related adverse events. A Bayesian network meta-analysis was performed. RESULTS: Olanzapine-based triple regimens showed significantly better no-nausea rate in overall phase and delayed phase than aprepitant-based triplet (odds ratios 3.18, 3.00, respectively), casopitant-based triplet (3.78, 4.12, respectively), fosaprepitant-based triplet (3.08, 4.10, respectively), rolapitant-based triplet (3.45, 3.20, respectively), and conventional duplex regimens (4.66, 4.38, respectively). CRs of olanzapine-based triplet were roughly equal to different NK-1RAs-based triplet but better than the conventional duplet. Moreover, no significant drug-related adverse events were observed in olanzapine-based triple regimens when compared with NK-1RAs-based triple regimens and duplex regimens. Additionally, the costs of olanzapine-based regimens were obviously much lower than the NK-1RA-based regimens. CONCLUSION: Olanzapine-based triplet stood out in terms of nausea control and drug price but represented no significant difference of CRs in comparison with NK-1RAs-based triplet. Olanzapine-based triple regimens should be an optional antiemetic choice for patients with HEC, especially those suffering from delayed phase nausea. IMPLICATIONS FOR PRACTICE: According to the results of this study, olanzapine-based triple antiemetic regimens were superior in both overall and delayed-phase nausea control when compared with various neurokinin-1 receptor antagonists-based triple regimens in patients with highly emetogenic chemotherapy (HEC). Olanzapine-based triplet was outstanding in terms of nausea control and drug price. For cancer patients with HEC, especially those suffering from delayed-phase nausea, olanzapine-based triple regimens should be an optional antiemetic choice.
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Náusea/prevenção & controle , Antagonistas dos Receptores de Neurocinina-1/uso terapêutico , Olanzapina/uso terapêutico , Vômito/prevenção & controle , Humanos , Náusea/induzido quimicamente , Náusea/tratamento farmacológico , Metanálise em Rede , Antagonistas dos Receptores de Neurocinina-1/farmacologia , Olanzapina/farmacologia , Vômito/induzido quimicamente , Vômito/tratamento farmacológicoRESUMO
Dispersive liquid-liquid microextraction (DLLME) coupled with CE was developed for simultaneous determination of five types of chlorophenols (CPs), namely 2-chlorophenol (2-CP), 4-chlorophenol (4-CP), 2,4-dichlorophenol (2,4-DCP), 2,6-dichlorophenol (2,6-DCP), and 2,4,6-trichlorophenol (2,4,6-TCP) in water samples. Several parameters affecting DLLME and CE conditions were systematically investigated. Under the optimized DLLME-CE conditions, the five CPs were separated completely within 7.5 min and good enrichment factors were obtained of 40, 193, 102, 15, and 107 for 4-CP, 2,4,6-TCP, 2,4-DCP, 2-CP, and 2,6-DCP, respectively. Good linearity was attained in the range of 1-200 µg/L for 2,4,6-TCP, 2,4-DCP, 2-300 µg/L for 4-CP and 2-CP, and 1-300 µg/L for 2,6-DCP, with correlation coefficients (r) over 0.99. The LOD (S/N = 3) and the LOQ (S/N = 10) were 0.31-0.75 µg/L and 1.01-2.43 µg/L, respectively. Recoveries ranging from 60.85 to 112.36% were obtained with tap, lake, and river water spiked at three concentration levels and the RSDs (for n = 3) were 1.31-11.38%. With the characteristics of simplicity, cost-saving, and environmental friendliness, the developed DLLME-CE method proved to be potentially applicable for the rapid, sensitive, and simultaneous determination of trace CPs in complicated water samples.
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Clorofenóis/análise , Eletroforese Capilar/métodos , Microextração em Fase Líquida/métodos , Poluentes Químicos da Água/análise , China , Clorofenóis/química , Clorofenóis/isolamento & purificação , Lagos/química , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Rios/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificaçãoRESUMO
A pretreatment method of dispersive solid-phase extraction (DSPE) along with back-extraction followed by CE-UV detector was developed for the determination of mercury species in water samples. Sulfhydryl-functionalized SiO2 microspheres (SiO2 -SH) were synthesized and used as DSPE adsorbents for selective extraction and enrichment of three organic mercury species namely ethylmercury (EtHg), methylmercury (MeHg), and phenylmercury (PhHg), along with L-cysteine (L-cys) containing hydrochloric acid as back-extraction solvent. Several main extraction parameters were systematically investigated including sample pH, amount of adsorbent, extraction and back-extraction time, volume of eluent, and concentration of hydrochloric acid. Under optimal conditions, good linearity was achieved with correlation coefficients over 0.9990, in the range of 4-200 µg/L for EtHg, and 2-200 µg/L for MeHg and PhHg. The LODs were obtained of 1.07, 0.34, and 0.24 µg/L for EtHg, MeHg, and PhHg, respectively, as well as the LOQs were 3.57, 1.13, and 0.79 µg/L, respectively, with enrichment factors ranging from 109 to 184. Recoveries were attained with tap and lake water samples in a range of 62.3-107.2%, with relative standard deviations of 3.5-10.1%. The results proved that the method of SiO2 -SH based DSPE coupled with CE-UV was a simple, rapid, cost-effective, and eco-friendly alternative for the determination of mercury species in water samples.
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BACKGROUND: Histone acetyltransferase p300 is a crucial transcriptional coactivator and has been implicated as a poor prognostic factor in human cancers. However, little is known about the substantial functions and mechanisms of p300 in NSCLC proliferation and distant metastasis. METHODS: We constructed p300 down-regulated and up-regulated cell lines through RNAi and recombinant plasmid transfection. Cell Counting Kit-8 assays were used to test the cell proliferation and confirmed by colony formation assays. Wound healing assays and transwell chamber assays were used to test the migration and invasion ability. Based upon these results, we measured the epithelial markers and mesenchymal markers after regulating p300 expression to explore epithelial-mesenchymal transition as a potential mechanism of p300 promoting NSCLC metastasis. RESULTS: In NSCLC cells NCI-H1975 and NCI-H1993, down-regulation of p300 leads to inhibition of cell proliferation and colony formation. Cells with reduced p300 expression also demonstrate inhibited migration and invasion ability. Contrarily, up-regulation of p300 significantly enhanced the proliferation, colony formation, migration and invasion ability of NCI-H460. Importantly, further investigation shows that decreased p300 expression is associated with reduced expression of mesenchymal markers and increased expression of epithelial markers, while up-regulated p300 expression correlated with decreased expression of epithelial markers and increased expression of mesenchymal markers. CONCLUSIONS: As a crucial tumor promoter, p300 promotes cell proliferation, migration, and invasion in NSCLC cells. Epithelial-mesenchymal transition is a potential mechanism of p300 promoting NSCLC metastasis.