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2.
Mol Ecol ; 32(24): 6939-6952, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37902115

RESUMO

Despite the known collective contribution of above- (plants) and below-ground (soil fungi) biodiversity on multiple soil functions, how the associations among plant and fungal communities regulate soil multifunctionality (SMF) differentially remains unknown. Here, plant communities were investigated at 81 plots across a typical arid inland river basin, within which associated soil fungal communities and seven soil functions (nutrients storage and biological activity) were measured in surface (0-15 cm) and subsurface soil (15-30 cm). We evaluated the relative importance of species richness and biotic associations (reflected by network complexity) on SMF. Our results demonstrated that plant species richness and plant-fungus network complexity promoted SMF in surface and subsurface soil. SMF in two soil layers was mainly determined by plant-fungus network complexity, mean groundwater depth and soil variables, among which plant-fungus network complexity played a crucial role. Plant-fungus network complexity had stronger effects on SMF in surface soil than in subsurface soil. We present evidence that plant-fungus network complexity surpassed plant-fungal species richness in determining SMF in surface and subsurface soil. Moreover, plant-fungal species richness could not directly affect SMF. Greater plant-fungal species richness indirectly promoted SMF since they ensured greater plant-fungal associations. Collectively, we concluded that interkingdom networks between plants and fungi drive SMF even in different soil layers. Our findings enhanced our knowledge of the underlying mechanisms that above- and below-ground associations promote SMF in arid inland river basins. Future study should place more emphasis on the associations among plant and microbial communities in protecting soil functions under global changes.


Assuntos
Rios , Solo , Microbiologia do Solo , Plantas/microbiologia , Biodiversidade , Fungos/genética , Ecossistema
3.
Heliyon ; 9(10): e20301, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37767513

RESUMO

The leachate sludge (LS) and fly ash (FA) are the foci of hazardous wastes which generated from the municipal solid waste incineration (MSWI). The current work developed a new way to use energy from MSWI process for the on-site sintering of LS and FA at a relatively low temperature. With the assistance of CaF2, granule of LS and MSWI FA were co-sintered. The influence of temperature, the mass of CaF2, and the mass ratio of LS/MSWI FA were investigated. As a result, heavy metals volatilization and leaching in the form of chlorinated salts were controlled. In addition, CaF2 improved the compressive strength of the granule under low-temperature sintering. Moreover, the scale-up co-sintering test was achieved in an MSWI chamber. The results showed that the optimum condition was sintering at 973K for 1 h. The compressive strength of sintered product reached 4.25 MPa, which met the standard of ceramic granule. Moreover, with the addition of CaF2, the volatilization rate of Pb, Zn, and Cd decreased by 6%, 7%, and 6%, respectively. This method can be a promising technique for the utilization of solid wastes.

4.
Anal Chim Acta ; 1269: 341414, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37290853

RESUMO

The development of microelectrodes for the rapid in situ detection of neurotransmitters and their metabolic levels in human biofluids has considerable significance in biomedical research. In this study, self-supported graphene microelectrodes with B-doped, N-doped, and B- and N-co-doped vertical graphene (BVG, NVG, and BNVG, respectively) nanosheets grown on horizontal graphene (HG) were fabricated for the first time. The high electrochemical catalytic activity of BVG/HG on monoamine compounds was explored by investigating the influence of B and N atoms and the VG layer thickness on the response current of neurotransmitters. Quantitative analysis using the BVG/HG electrode in a blood-like environment with pH 7.4 indicated that the linear concentration ranges were 1-400 and 1-350 µM for dopamine (DA) and serotonin (5-HT), with limits of detection (LODs) of 0.271 and 0.361 µM, respectively. For tryptophan (Trp), the sensor measured a wide linear concentration range of 3-1500 µM over a wide pH range of 5.0-9.0, with the LOD fluctuating between 0.58 and 1.04 µM. Furthermore, the BVG/HG microelectrodes could be developed as needle- and pen-type sensors for the detection of DA, 5-HT, and Trp in human blood and gastrointestinal secretion samples.


Assuntos
Grafite , Humanos , Microeletrodos , Grafite/química , Serotonina/análise , Oxirredução , Limite de Detecção , Dopamina/análise , Técnicas Eletroquímicas
5.
Dalton Trans ; 51(11): 4394-4399, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35194625

RESUMO

Low-valent metal complexes have attracted much research interest owing to their novel reactivities toward small molecules. Herein the reactivity of the α-diimine-ligated, Mg-Mg-bonded compound [K(THF)3]2[LMg-MgL] (1, L = [(2,6-iPr2C6H3)NC(Me)]22-) with aliphatic nitriles has been studied. Complex 1 readily activates n-alkylnitriles (RCN; R = propyl, butyl, and pentyl) to afford the unique trinuclear magnesium metallo-macrocyclic complexes, [LMg(µ-{(NC-C(R)C(CH2R)-NH})]3[K3(Solv)6] (2-4: R = -(CH2)nCH3, n = 2, 3, or 4; Solv = THF/DME), through a reductive deprotonation of the α-H of one nitrile molecule and C-C coupling between this α-carbon and the cyanide (CN) group of another nitrile, followed by a 1,3-H shift. The results demonstrate the possibility of assembling supramolecular architectures based on the α-diimine [LMg] fragment through small molecule activation.

6.
Chem Commun (Camb) ; 57(51): 6268-6271, 2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34075952

RESUMO

Dialumane 1 reacts with pyridines at elevated temperatures through regioselective reductive dehydrogenation of 4-H, affording a unique hexanuclear Al(iii) macrocycle [{LAl(pyridyl)}6], which represents the first dialumane-mediated C-H activation of Py and may suggest a new approach toward organometallo supra-molecules by one-pot small molecule activation and self-assembly.

8.
Chem Commun (Camb) ; 56(47): 6352-6355, 2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-32390025

RESUMO

The dialumane [L2-AlII-AlIIL2-] (L = [(2,6-iPr2C6H3)NC(Me)]2; 1) reacts with carbodiimides, RN[double bond, length as m-dash]C[double bond, length as m-dash]NR (R = Cy, iPr), through insertion, [2+4] cycloaddition, and a hydrogen transfer process. However, with the bulkier carbodiimides (R = dipp = 2,6-iPr2C6H3, tBu), the reactions are sterically controlled and lead to the formamidinate products.

9.
Fish Shellfish Immunol ; 90: 102-108, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31048038

RESUMO

The suppressor of cytokine signaling (SOCS) family members play crucial roles in regulating immune signal pathways by acting as inhibitors of cytokine receptor signaling. In this study, 10 SOCS genes were identified in soiny mullet (Liza haematocheila), an economically important aquaculture mugilid species in China and other Asian countries. Sequence comparison showed that the sequence identity between mullet SOCSs and their counterparts from other vertebrates ranged from 38.2% to 92.5%. All mullet SOCS genes were constitutively expressed in tissues examined, but their expression patterns were different. Further, following Streptococcus dysgalactiae infection, all mullet SOCS genes exhibited distinct expression patterns in tissues. These results suggest that SOCSs are involved in immune response to bacterial infection and provide the basis for understanding the complex cytokine regulatory network of teleosts.


Assuntos
Doenças dos Peixes/imunologia , Proteínas de Peixes/genética , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Smegmamorpha/genética , Proteínas Supressoras da Sinalização de Citocina/genética , Animais , Proteínas de Peixes/metabolismo , Perfilação da Expressão Gênica/veterinária , Análise de Sequência de DNA/veterinária , Análise de Sequência de Proteína/veterinária , Smegmamorpha/metabolismo , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/veterinária , Streptococcus/fisiologia , Proteínas Supressoras da Sinalização de Citocina/metabolismo
10.
Front Pharmacol ; 10: 406, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31105562

RESUMO

Traumatic brain injury (TBI) is one of the most common causes of neurological damage in young human populations. Vitamin B12 has been reported to promote axon growth of neuronal cells after peripheral nerve injury, which is currently used for the treatment of peripheral nerve damage in the clinical trial. Thus, we hypothesized that TBI can be attenuated by vitaminB12 treatment through its beneficial role on axon regeneration after nerve injury. To confirm it, the biological function of vitaminB12 was characterized using hematoxylin and eosin (H&E) staining, Luxol fast blue (LFB) staining, western blot analysis, and immunohistochemistry staining. The results showed that the neurological functional recovery was improved in the VitaminB12-treated group after TBI, which may be due to downregulation of the endoplasmic reticulum stress-related apoptosis signaling pathway. Moreover, the microtubule stabilization, remyelination and myelin reparation were rescued by vitamin B12, which was consistent with the treatment of 4-phenylbutyric acid (4-PBA), an endoplasmic reticulum stress inhibitor. The study suggests that vitamin B12 may be useful as a novel neuroprotective drug for TBI.

11.
Dev Comp Immunol ; 99: 103401, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31145914

RESUMO

The interleukin (IL) -1 family members play an important role in regulating inflammatory responses and their functions are mediated by a group of receptors consisting of immunoglobulin and Toll/IL-1 receptor (TIR) domains. In humans, 10 IL-1Rs are found. In this study, 5 IL-1 receptors including IL-1R3/IL-1RAcP, IL-1R8/SIGIRR, IL-1R9a/IL-1RAcPL1a, IL-1R9b/IL-1RAcPL1b and IL-1R10/IL-1RAcPL2 were identified in grass carp (Ctenopharyngodon idella). Phylogenetic analysis reveals that the IL-1R9a/IL-1RAcPL1a and IL-1R9b/IL-1RAcPL1b share significantly high sequence similarity and are believed to have been duplicated from the same gene prior to the radiation of teleosts. Further, these two receptors closely relate to the IL-1R10/IL-1RAcPL2, suggesting that they may have evolved from a common ancestor. The IL-1R3/IL-1RAcP, IL-1R9a/IL-1RAcPL1a, IL-1R9b/IL-1RAcPL1b and IL-1R10/IL-1RAcPL2 are highly expressed in the brain. Stimulation of primary spleen leucocytes by LPS and intraperitoneal injection of fish with poly (I:C) or bacterial infection results in significant increases of IL-1R3/IL-1RAcP expression. Interestingly, the IL-1R8/SIGIRR and IL-1R10/IL-1RAcPL2 showed similar expression patterns.


Assuntos
Carpas/classificação , Carpas/imunologia , Proteínas de Peixes/genética , Regulação da Expressão Gênica/imunologia , Filogenia , Receptores de Interleucina-1/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Carpas/genética , Células Cultivadas , Evolução Molecular , Proteínas de Peixes/química , Proteínas de Peixes/imunologia , Duplicação Gênica , Expressão Gênica , Imunidade Inata/genética , Receptores de Interleucina-1/química , Receptores de Interleucina-1/metabolismo , Alinhamento de Sequência , Distribuição Tecidual
12.
Fish Shellfish Immunol ; 92: 91-100, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31146007

RESUMO

Interleukin (IL) 34 plays an important role in regulating macrophage functions and inflammation process. IL-34 homologues have recently been discovered in fish but the functions have not been studied. In this study, an IL-34 homologue was identified in grass carp Ctenopharyngodon idella and its bioactivities were investigated. The grass carp IL-34 was constitutively expressed in tissues, with the highest expression detected in spleen. It could be up-regulated in spleen after infection with F. cloumnare and grass carp reovirus II, and in primary head kidney leucocytes by recombinant IL-4/13B. The recombinant IL-34 produced in bacteria and HEK293T cells showed stimulatory effect on the expression of IL-1ß, IL-6 and IL-8 but inhibited expression of IL-10 and TGF-ß1 in primary head kidney macrophages. The results demonstrate that IL-34 is a proinflammatory cytokine in grass carp.


Assuntos
Carpas/genética , Carpas/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Interleucinas/genética , Interleucinas/imunologia , Sequência de Aminoácidos , Animais , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Infecções por Flavobacteriaceae/imunologia , Infecções por Flavobacteriaceae/veterinária , Flavobacterium/fisiologia , Perfilação da Expressão Gênica/veterinária , Células HEK293 , Humanos , Interleucinas/química , Filogenia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Reoviridae/fisiologia , Infecções por Reoviridae/imunologia , Infecções por Reoviridae/veterinária , Alinhamento de Sequência/veterinária
13.
Chem Commun (Camb) ; 55(23): 3363-3366, 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30816396

RESUMO

YCoxFe1-xO3 perovskite oxides were prepared using a modified sol-gel method with SBA-15 as a hard template. Pt nanoparticles supported on YCo0.3Fe0.7O3 perovskite oxides can furnish as high as 94.9% selectivity to cinnamyl alcohol at nearly full conversion, with the initial activity (TOF) reaching 15 163 h-1 for the selective hydrogenation of cinnamaldehyde.

14.
Fish Shellfish Immunol ; 87: 254-264, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30630048

RESUMO

Interleukin (IL)-4 and IL-13 are T helper 2 (Th2) cytokines with pleiotropic functions. IL-4 interacts with two receptors consisting of IL-4Rα/γ chain receptor (γC) and IL-4Rα/IL-13Rα1. In contrast, IL-13 binds to IL-13Rα2 but also shares the receptor complex containing IL-4Rα/IL-13Rα1. In fish, two IL-4/13 homologs have been identified but their phylogenetic relationships with IL-4 and IL-13 are ambiguous. In this study, we identified six putative IL-4/13 receptor homologs in grass carp, including γC1, γC2, IL-4Rα1, IL-13Rα1, IL-13Rα2 and a soluble form of IL-4Rα2. Comparative sequence analyses revealed that these receptors possess conserved characteristic domains and the genes encoding them share conserved gene synteny with their human counterparts. All six receptors contain a cytokine binding homology domain (CHD) and two fibronectin type Ⅲ (FNⅢ) like domains, with IL-13Rα1 and IL-13Rα2 harbouring an extra Ig-like domain preceding the CHD domain. Interestingly, grass carp IL-13Rα1 and IL-13Rα2 lack the characteristic WSXWS motif, a typical feature of mammalian type I cytokine receptors. The IL-4/13 receptor genes are differentially expressed in tissues and primary leukocytes of head kidney and can be modulated by Flavobacterium cloumnare (F. cloumnare), suggesting they are involved in immune response against F. cloumnare infection.


Assuntos
Carpas/genética , Carpas/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Receptores Tipo II de Interleucina-4/genética , Receptores Tipo II de Interleucina-4/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Infecções por Flavobacteriaceae/imunologia , Infecções por Flavobacteriaceae/veterinária , Flavobacterium/fisiologia , Perfilação da Expressão Gênica/veterinária , Filogenia , Receptores Tipo II de Interleucina-4/química , Alinhamento de Sequência/veterinária
15.
Int J Clin Exp Pathol ; 12(9): 3301-3310, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31934173

RESUMO

CREPT has been shown to be highly expressed in most tumors and is associated with a poor prognosis, but the histologic characteristics of CREPT expression and its impact on clinical outcomes in esophageal squamous cell carcinoma (ESCC) are unclear. Therefore, we retroactively evaluated tissue microarrays (TMA) from 300 surgical cases, including 300 ESCC tissues and 161 adjacent non-tumor tissues, and pretreatment tumor biopsies from 113 concurrent chemoradiotherapy (CCRT) cases by immunohistochemistry (IHC). Notably, CREPT was increasingly expressed from non-cancerous tissues to atypical hyperplasia to tumor tissues (P < 0.01). Furthermore, patients were divided into low CREPT (≤ 8 scores) and high CREPT (> 8 scores) groups. Patients with high CREPT expressions had a worse overall survival (OS) (5-year OS: 40.9% vs. 50.1%, P=0.040) and disease-free survival (DFS) (5-year DFS: 29.5 vs. 43.0%; P=0.020) than those with low expressions. Nevertheless, only in the high CREPT subgroup did adjuvant therapy (AT) prolong the OS (5-year OS: 53.8 vs. 28.9%; P=0.020), especially for adjuvant radiotherapy (ART) (5-year OS: 85.7 vs. 28.9%; P=0.037; 5-year DFS: 85.7 vs. 22.3%; P=0.020). Surprisingly, high CREPT expressions endowed CCRT-treated patients with higher complete response rates (50% vs. 26%; P=0.018) and a favorable OS (3-year OS: 54.3 vs. 28.1%; P=0.046) compared to low expression. Overall, our findings indicate that CREPT is highly expressed in ESCC tissue compared with non-cancerous tissue and this feature is associated with a poor prognosis. Otherwise, patients with high CREPT expression were more sensitive to AT and CCRT. Moreover, CREPT could be a predictive immunohistochemical biomarker used to guide individualized clinical treatment.

16.
BMC Cancer ; 18(1): 147, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29409459

RESUMO

BACKGROUND: Increasing evidence shows that dysregulated long non-coding RNAs (lncRNAs) can serve as potential biomarkers for cancer prognosis. However, lncRNA signatures, as potential prognostic biomarkers for esophageal squamous cell carcinoma (ESCC), have been seldom reported. METHODS: Based on our previous transcriptome RNA sequencing analysis from 15 paired ESCC tissues and adjacent normal tissues, we selected 10 lncRNAs with high score rank and characterized the expression of those lncRNAs, by qRT-PCR, in 138 ESCC and paired adjacent normal samples. These 138 patients were divided randomly into training (n = 77) and test (n = 59) groups. A prognostic signature of lncRNAs was identified in the training group and validated in the test group and in an independent cohort (n = 119). Multivariable Cox regression analysis evaluated the independence of the signature in overall survival (OS) and disease-free survival (DFS) prediction. GO and KEGG pathway analysis, combined with cell transwell and proliferation assays, are applied to explore the function of the three lncRNAs. RESULTS: A novel three-lncRNA signature, comprised of RP11-366H4.1.1 (ENSG00000248370), LINC00460 (ENSG00000233532) and AC093850.2 (ENSG00000230838), was identified. The signature classified patients into high-risk and low-risk groups with different overall survival (OS) and disease-free survival (DFS). For the training group, median OS: 23.1 months vs. 39.1 months, P < 0.001; median DFS: 15.2 months vs. 33.3 months, P < 0.001. For the test group, median OS: 23 months vs. 59 months, P < 0.001; median DFS: 16.4 months vs. 50.8 months, P < 0.001. For the independent cohort, median OS: 22.4 months vs. 60.4 months, P < 0.001). The signature indicates that patients in the high-risk group show poor OS and DFS, whereas patients with a low-risk group show significantly better outcome. The independence of the signature was validated by multivariable Cox regression analysis. GO and KEGG pathway analysis for 588 protein-coding genes-associated with the three lncRNAs indicated that the three lncRNAs were involved in tumorigenesis. In vitro assays further demonstrated that the three lncRNAs promoted the migration and proliferation of ESCC cells. CONCLUSIONS: The three-lncRNA signature is a novel and potential predictor of OS and DFS for patients with ESCC.


Assuntos
Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , RNA Longo não Codificante/genética , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/diagnóstico , Linhagem Celular Tumoral , Intervalo Livre de Doença , Neoplasias Esofágicas/diagnóstico , Feminino , Perfilação da Expressão Gênica/estatística & dados numéricos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais
17.
Nutr Cancer ; 69(1): 21-28, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27898225

RESUMO

Riboflavin is an essential micronutrient for normal cellular activity, and deficiency may result in disease, such as cancer. We performed a case-control study to explore the association of riboflavin levels with risk and prognosis of esophageal squamous cell carcinoma (ESCC). Plasma riboflavin levels, as measured by enzyme-linked immunosorbent assay (ELISA), in ESCC patients were significantly lower than in those of healthy controls (7.04 ± 6.34 ng/ml vs. 9.32 ± 12.40 ng/ml; P < 0.05). Moreover, there was an inverse relationship between riboflavin level and risk of ESCC (odds ratio (OR) = 0.97, 95% confidence interval (CI) = 0.95-0.99, P =  0.02). The 5-year relapse-free and overall survival rates were significantly lower when riboflavin levels were ≤0.8 ng/ml than >0.8 ng/ml (relapse-free survival rate: 29.4% vs. 54.8%; overall survival rate: 28.6% vs. 55.6%). Plasma riboflavin level was an independent protective factor for both relapse-free (hazard ratio (HR) = 0.325, 95% CI = 0.161-0.657, P = 0.002) and overall survival of ESCC patients (HR = 0.382, 95% CI = 0.190-0.768, P = 0.007). In conclusion, plasma riboflavin levels are significantly related to risk and prognosis of ESCC patients, suggesting that moderate supplementation of riboflavin will decrease risk and prevent recurrence of ESCC and also improve prognosis of ESCC patients.


Assuntos
Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Riboflavina/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Carcinoma de Células Escamosas/sangue , Estudos de Casos e Controles , Neoplasias Esofágicas/sangue , Carcinoma de Células Escamosas do Esôfago , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Proteínas de Membrana Transportadoras/genética , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Prognóstico
18.
Environ Sci Pollut Res Int ; 24(6): 5238-5248, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28004365

RESUMO

Antibiotics are emerging contaminants due to their potential risks to human health and ecosystems. Poor biodegradability makes it necessary to develop effective physical-chemical methods to eliminate these contaminants from water. The cobalt-modified MCM-41 was prepared by a one-pot hydrothermal method and characterized by SAXRD, N2 adsorption-desorption, SEM, UV-Vis DR, and FTIR spectroscopy. The results revealed that the prepared 3% Co-MCM-41 possessed mesoporous structure with BET surface areas at around 898.5 m2g-1. The adsorption performance of 3% Co-MCM-41 toward levofloxacin (LVF) was investigated by batch experiments. The adsorption of LVF on 3% Co-MCM-41 was very fast and reached equilibrium within 2 h. The adsorption kinetics followed the pseudo-second-order kinetic model with the second-order rate constants in the range of 0.00198-0.00391 g mg-1 min-1. The adsorption isotherms could be well represented by the Langmuir, Freundlich, and Dubinin-Radushkevich (D-R) isotherm equations. Nevertheless, D-R isotherm provided the best fit based on the coefficient of determination and average relative error values. The mean free energy of adsorption (E) calculated from D-R model was about 11 kJ mol-1, indicating that the adsorption was mainly governed by a chemisorption process. Moreover, the adsorption capacity was investigated as a function of pH, adsorbent dosage, LVF concentration, and temperature with help of respond surface methodology (RSM). A quadratic model was established, and an optimal condition was obtained as follows: pH 8.5, adsorbent dosage of 1 g L-1, initial LVF concentration of 119.8 mg L-1, and temperature of 31.6 °C. Under the optimal condition, the adsorption capacity of 3% Co-MCM-41 to LVF could reach about 108.1 mg g-1. The solution pH, adsorbent dosage, LVF concentration, and a combination of adsorbent dose and LVF concentration were significant factors affecting the adsorption process. The adsorption thermodynamic functions were also determined. The negative ΔH 0 (-33.50 kJ mol-1) and ΔS 0 (-43.57 J mol-1 K-1) suggested that the adsorption was an exothermic process accompanied by decreasing disorder. This study may indicate that 3% Co-MCM-41 is a promising adsorbent for removing emerging pollutants of LVF from water.


Assuntos
Levofloxacino , Dióxido de Silício , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termodinâmica , Água/química , Poluentes Químicos da Água
19.
Clin Cancer Res ; 22(3): 691-703, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26405196

RESUMO

PURPOSE: STAT3 is known to have both oncogenic and tumor suppressive effects, but the regulation of these opposing effects is elusive. We hypothesized that STAT3ß, one of the two STAT3 isoforms, is the key determinant in this context. EXPERIMENTAL DESIGN: The prognostic significance of STAT3ß and phospho-STAT3α(Y705) (pSTAT3α(Y705)) was evaluated in 286 cases of patients with esophageal squamous cell carcinoma (ESCC). STAT3ß-induced changes in the chemosensitivity to cisplatin and 5-fluorouracil were assessed both in vitro and in vivo. STAT3ß-induced changes in the frequency of cancer stem cells were evaluated using Hoechst and CD44 staining. How STAT3ß regulates STAT3α was determined using immunoprecipitation, confocal microscopy, DNA-binding, and chromatin immunoprecipitation-PCR. RESULTS: STAT3ß expression is an independent protective prognostic marker in patients with ESCC, which strongly correlated with longer overall survival (P = 0.0009) and recurrence-free survival (P = 0.0001). STAT3ß significantly decreased the cancer stem cell population, and sensitized ESCC cells to cisplatin and 5-fluorouracil in tumor xenografts. Mechanistically, STAT3ß markedly attenuated the transcription activity of STAT3α via inducing STAT3α:STAT3ß heterodimers. However, the heterodimer formation decreased the binding between STAT3α and PTPN9 (better known as PTP-MEG2), a protein tyrosine phosphatase, thereby promoting the phosphorylation of STAT3α(Y705) and enhancing its nuclear translocation and DNA binding. Correlating with this, high STAT3ß expression converts the prognostic value of pSTAT3α(Y705) from unfavorable to favorable in patients with ESCC. CONCLUSIONS: STAT3ß suppresses chemoresistance and cancer stemness by blocking the transcriptional activity of STAT3α. The paradoxical increase in pSTAT3α(Y705) induced by STAT3ß carries important implications as to how the biologic and prognostic significance of STAT3 in cancers should be interpreted.


Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteínas Oncogênicas , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Proteínas Supressoras de Tumor , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/mortalidade , Linhagem Celular Tumoral , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/mortalidade , Carcinoma de Células Escamosas do Esôfago , Humanos , Imuno-Histoquímica , Modelos Biológicos , Células-Tronco Neoplásicas/metabolismo , Fosforilação , Prognóstico , Multimerização Proteica , Proteínas Tirosina Fosfatases/metabolismo , Fator de Transcrição STAT3/química , Ativação Transcricional , Ensaios Antitumorais Modelo de Xenoenxerto
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