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1.
Clin Chim Acta ; 501: 42-47, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31816287

RESUMO

PURPOSE: FIT-DNA test is supposed to be highly sensitive for advanced colorectal neoplasms and is advocated in some developed countries, but lack extensive use in developing countries. METHODS: A case control study on stool DNA test for colorectal neoplasms patients was conducted from March 2016 to October 2017 in China. We recruited CRC, colorectal neoplasms and normal controls from ambulatory patients and screening attendees in communities. The stool DNA was tested by a molecular panel similar as ColoGuard in addition to fecal immunochemical test(FIT) in a blinded manner. A risk scoring system was used to determine the positiveness of tests with histological diagnosis as its reference standard. RESULTS: Eligible subjects included 203 colorectal cancer (CRC), 49 advanced adenoma (AA), 156 non-advanced adenoma(NAA) and 431 normal controls(NC). The FIT-DNA kit detected 97.5% CRC (n = 198, 95% CI = 95.4-99.7) and 53.1% AA (n = 26, 95% CI = 39.1-67.0), with specificity of 89.1% (95% CI = 86.2-92.0) in NC and 88.1% (95% CI = 85.5-90.7) in non-advanced controls. The FIT embedded in the kit alone identified 94.6% (n = 192, 95% CI = 91.5-97.7) CRC and 36.7% AA (n = 18, 95% CI = 23.2-50.2). Consistency of KRAS mutation, BMP3 methylation, NDRG4 methylation in 26 paires stool DNA and CRC tumor DNA were 80.9%, 71.4% and 81.8%, respectively. CONCLUSION: At the sacrifice of significantly decreased specificity, a FIT-DNA kit may has better sensitivity than FIT for predicting advanced colorectal adenoma, but not for predicting colorectal cancer. More evidences are needed for the extensive use of FIT-DNA testing.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 226: 117649, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31629983

RESUMO

The protamine capped gold nanoclusters (AuNCs@PRT) were synthesized by an one-pot approach, and utilized as a nanoprobe for highly sensitive and selective assay of U(VI) ions. The method is based on the aggregation induced fluorescent quenching of AuNCs@PRT by U(VI) ions. Under optimum conditions, the decrease of fluorescence intensity displayed a good linear correlation with the concentration of U(VI) ions ranging from 20.4 nM to 9.74 µM, with a detection limit of 6.1 nM. The relative standard deviations were 3.86%, 1.41% and 1.71% via 11 detections at concentrations of 40 nM, 0.40 µM and 4.0 µM of U(VI), respectively. The quenching mechanism was demonstrated to be due to the binding of U(VI) towards PRT to cause the aggregation of AuNCs@PRT rather than metal-metal interaction. The results suggest the potential application of this approach for monitoring the level of U(VI) in environmental samples.

3.
Int J Cancer ; 146(7): 2027-2035, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31693169

RESUMO

The heterogeneities of colorectal cancer (CRC) lead to staging inadequately of patients' prognosis. Here, we performed a prognostic analysis based on the tumor mutational profile and explored the characteristics of the high-risk tumors. We sequenced 338 colorectal carcinomas as the training dataset, constructed a novel five-gene (SMAD4, MUC16, COL6A3, FLG and LRP1B) prognostic signature, and validated it in an independent dataset from The Cancer Genome Atlas (TCGA). Kaplan-Meier and Cox regression analyses confirmed that the five-gene signature is an independent predictor of recurrence and prognosis in patients with Stage III colon cancer. The mutant signature translated to an increased risk of death (hazard ratio = 2.45, 95% confidence interval = 1.15-5.22, p = 0.016 in our dataset; hazard ratio = 4.78, 95% confidence interval = 1.33-17.16, p = 0.008 in TCGA dataset). RNA and bacterial 16S rRNA sequencing of high-risk tumors indicated that mutations of the five-gene signature may lead to intestinal barrier integrity, translocation of gut bacteria and deregulation of immune response and extracellular related genes. The high-risk tumors overexpressed IL23A and IL1RN genes and enriched with cancer-related bacteria (Bacteroides fragilis,Peptostreptococcus, Parvimonas, Alloprevotella and Gemella) compared to the low-risk tumors. The signature identified the high-risk group characterized by gut bacterial translocation and upregulation of interleukins of the tumor microenvironment, which was worth further researching.

4.
Molecules ; 24(20)2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31635023

RESUMO

The total synthesis of potent anti-obesity lansiumamide B was accomplished in four steps using commercially available materials. The synthetic strategy, featured with copper-catalyzed Buchwald coupling, is concise, convergent, practical and can be carried out on a one-gram scale. This approach could give either Z- or E-configured enamide moiety in natural products with absolute stereocontrol and was applied in the total synthesis of natural products.

5.
J Biol Chem ; 294(43): 15768-15780, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31488545

RESUMO

Intracellular pH and redox states are critical for multiple processes and partly determine cell behavior. Here, we developed a genetically encoded dual-function probe, named p H and redox-sensitive fluorescent protein (pHaROS), for simultaneous real-time detection of changes in redox potential and pH in living cells. pHaROS consists of the Arabidopsis flavin mononucleotide-binding fluorescent protein iLOV and an mKATE variant, mBeRFP. Using pHaROS in Saccharomyces cerevisiae cells, we confirmed that H2O2 raises the overall redox potential of the cell and found that this increase is accompanied by a decrease in cytosolic pH. Furthermore, we observed spatiotemporal pH and redox homeostasis within the nucleus at various stages of the cell cycle in budding yeast (Saccharomyces cerevisiae) during cellular development and responses to oxidative stress. Importantly, we could tailor pHaROS to specific applications, including measurements in different organelles and cell types and the GSH/GSSG ratio, highlighting pHaROS's high flexibility and versatility. In summary, we have developed pHaROS as a dual-function probe that can be used for simultaneously measuring cellular pH and redox potential, representing a very promising tool for determining the cross-talk between intracellular redox- and pH-signaling processes in yeast and mammalian U87 cell.

6.
BMC Cancer ; 19(1): 47, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30630450

RESUMO

BACKGROUND: To date, no single colorectal cancer (CRC) screening strategy has been determined to be applicable worldwide. In China, a CRC screening protocol that combines double fecal immunochemical tests (FITs) and a high-risk factor questionnaire (HRFQ) as the first stage of screening and colonoscopy as the second stage of screening (scenario A) was adapted by the Chinese Ministry of Health in 2006. However, applying this CRC screening protocol nationally remains difficult because its effectiveness and convenience are controversial. This study evaluated the effects of subitems of the CRC screening protocol in China. METHODS: CRC screening results (scenario A) from Jiashan County, China, (2007-2009) were used to analyze the detection rates of CRC and advanced neoplasms as well as the cost-effectiveness of the protocol. Scenario A was divided into scenarios B-G (by selecting some items at the first stage of screening) for analysis. RESULTS: Compared with scenario A, removing the whole HRFQ (scenario F) reduced advanced neoplasm and adenoma detections by 29.8 and 41.2%, respectively, whereas the whole HRFQ accounted for 10.1% of the total screening cost. Removing FITs (scenario G) reduced CRC, advanced neoplasm and adenoma detections by 71.8, 56.9 and 47.7%, respectively, and the costs per case of CRC and advanced neoplasm were 82.0 and 19.1% higher, respectively, than those in scenario A. In scenarios B-E (deleting some high-risk factor questions on the HRFQ), the odds ratios (ORs) of the detection rates and costs per CRC, advanced neoplasm, adenoma, and neoplasm case were near 1.00. Scenarios C and D reduced the high-risk population and total screening costs by less than 6.0 and 4.1%, respectively. Scenarios E and B (FITs and a personal history of cancer or colorectal adenoma were reserved) reduced the high-risk population by 17.6 and 24.2% and the total screening costs by 11.2 and 15.4%, respectively, while the numbers of CRC cases were not missed, and advanced neoplasms detected decreased by only 5 and 11%, respectively. CONCLUSION: The results of this study demonstrate that FITs and a personal history of colorectal adenoma are the most effective items in the Chinese CRC screening protocol.


Assuntos
Neoplasias Colorretais/epidemiologia , China/epidemiologia , Neoplasias Colorretais/diagnóstico , Detecção Precoce de Câncer , Feminino , Humanos , Masculino , Programas de Rastreamento , Razão de Chances , Vigilância em Saúde Pública , Fatores de Risco
7.
Mikrochim Acta ; 185(10): 483, 2018 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-30269212

RESUMO

The authors report on a one-pot approach for synthesizing highly fluorescent protamine-stabilized gold nanoclusters. These are shown to be a viable nanoprobe for selective and sensitive fluorometric determination of lead(II) via quenching of fluorescence via Pb(II)-Au(I) interaction. Under optimized conditions, fluorescence measured at excitation/emission peaks of 300/599 nm drops in the 80 nM-15 µM lead(II) concentration range. The detection limit is 24 nM, and relative standard deviations (for n = 11) at concentrations of 0.10, 4.0 and 15 µM are 1.6, 2.5 and 1.9%, respectively. The relative recoveries of added lead(II) in the water samples ranged from 97.9 ± 2.29% to 101.2 ± 1.83%. Graphical abstract Lead(II) ions are found to be able to selectively and sensitively quench the fluorescence of the protamine-gold nanoclusters (PRT-AuNCs). Thereby, an inexpensive, selective and sensitive lead(II) assay was established.

8.
Anal Bioanal Chem ; 410(28): 7385-7394, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30215122

RESUMO

We certify that protamine-gold nanoclusters (PRT-AuNCs) synthesized by one-pot method exhibit peroxidase-like activity. The catalytic activity of PRT-AuNCs followed typical Michaelis-Menten kinetics and exhibited higher affinity to 3,3',5,5'-tetramethylbenzidine (TMB) as the substrate compared to that of natural horseradish peroxidase. Meanwhile, we found that Hg(II) could dramatically and selectively enhance the peroxidase-like activity of PRT-AuNCs, and the enhanced mechanism by Hg(II) was demonstrated to be generation of the cationic Au species and the partly oxidized Au species (Auδ+) by Hg2+-Au0/Au+ interaction. Based on this finding, quantitative determinations of Hg(II) via visual observation and absorption spectra were achieved. The proposed strategy displays high selectivity that arises from the strong aurophilic interaction of mercury towards gold. Moreover, the developed method is highly sensitive with a wide linear range and low detection limit of 1.16 nM. This strategy is not only helpful to develop effective nanomaterials-based artificial enzyme mimics but also irradiative to discover new applications of artificial mimic enzymes in bio-detection, medical diagnostics, and biotechnology. Graphical abstract Protamine-gold nanoclusters (PRT-AuNCs) synthesized by one-pot method exhibit peroxidase-like activity. Hg(II) can stimulate the peroxidase-like activity of PRT-AuNCs selectively, enhancing their ability to catalyze the chromogenic reaction of TMB by H2O2.


Assuntos
Colorimetria/métodos , Ouro/química , Mercúrio/química , Nanopartículas Metálicas/química , Peroxidases/metabolismo , Protaminas/química , Cinética , Peroxidases/química , Sensibilidade e Especificidade
9.
Bioresour Technol ; 267: 17-29, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30007235

RESUMO

The aim of this work was to study the correlation between dynamic mechanisms of carbon structure associated with their upgrading effects with the help of XPS, 13C NMR and 2D-PCIS methods. Results showed the fuel qualifies of biowastes were improved and became comparable to lignite or even bitumite after HTC. The carbon chemical bonds of -C-H and -C-O in biowaste components (mainly protein and polysaccharide) were thermally cracked and enriched in liquid phase in the form of soluble intermediates, which subsequently generated coal-like structures via cyclization as well as polymerization at higher temperatures. The further investigation on thermogravimetric analysis found that the conversion of "-C-H/C-O to aromatic -C-C/CC" was beneficial for stabilizing their combustion behavior by integrating two stages of biowastes (devolatilization stage and combustion stage) into one stage of hydrochars (combustion stage).


Assuntos
Carbono , Carvão Mineral , Temperatura Alta , Temperatura Ambiente , Termogravimetria
10.
J Environ Sci (China) ; 69: 261-270, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29941262

RESUMO

Sewage sludge (SS) and deinking sludge (DS) were used to comparatively study the hydrothermal dewatering of sludge with different components. For a better overview, an insight into the relationship between physicochemical properties and dewaterability of hydrothermal sludge was provided. Results found that not all kinds of sludge were suitably conditioned by hydrothermal treatment (HT) in term of the elevation of dewaterability. Higher hydrothermal temperature tended to enhance the dewaterability of SS rather than DS, which was supported by the variation of their physicochemical properties (including water distribution, bonding energy, extracellular polymeric substance (EPS), particles size, acid functional groups and zeta potential in this study). In addition, the changes in surface morphology suggested that the reverse effect of HT on sludge dewaterability was mainly due to their dewatering behavior. For SS, the destruction of EPS structure leaded to the release of bound water, thereby strengthening sludge dewatering. Conversely, "Bridging effect" generated by lignocellulose in DS was beneficial for sludge dewatering; however, the increasing hydrothermal temperature degraded part of lignocellulose and weakened "bridging effect", finally resulting in worse dewaterability of DS.


Assuntos
Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Dessecação , Temperatura Alta , Tamanho da Partícula , Polímeros , Temperatura Ambiente
11.
Oncol Lett ; 15(6): 9766-9776, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29928351

RESUMO

The gastrointestinal (GI) tract is not a common site of metastasis in primary lung cancer. The aim of the present study was to reveal the clinical and prognostic characteristics of gastrointestinal metastases of lung cancer (GMLC). Information on 366 cases of GMLC was collected and factors that affect severe GI complications were analyzed. Univariate and multivariate survival analyses were performed using the Cox proportional hazards model. Of the cases analyzed, the small intestine (59.6%) and colorectum (25.6%) were the two organs where lung cancer was most likely to metastasize in the GI tract. Squamous cell carcinoma (28.5%), adenocarcinoma (27.6%) and large cell carcinoma (20.9%) were the three most common histological types. However, compared with the histological distributions of primary lung cancer, patients with large cell carcinoma exhibited the highest elevated risk of GMLC [relative risk (RR), 4.07; P<0.001] and those with adenocarcinoma exhibited the lowest risk (RR, 0.58; P<0.001). Differences in organ involvement and in histological type led to varying GI complications. It was also indicated that chemotherapy was associated with a decreased risk of hemorrhage (P=0.006), but there was no reduction in the risk of hemorrhage associated with perforation and obstruction (P>0.05). The median overall survival time of GMLC patients was 2.8 months (range, 0-108 months). The survival analyses revealed that perforation and extra-GI metastasis were negative prognostic factors but abdominal surgery was identified a positive prognostic factor. In conclusion, the histological distribution of GMLC differed from that of primary lung cancer. Sufficient and careful patient evaluation, targeted surgeries and systemic therapies for specific patients are able to increase patient survival rate and improve the quality of life.

12.
J Cancer ; 9(3): 540-547, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29535795

RESUMO

The serum protein markers of colorectal adenoma in patients with a family history of colorectal cancer have been rarely reported. Serum samples from colorectal adenoma patients with or without a family history of colorectal cancer and healthy controls were profiled using Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF-MS). The model to distinguish colorectal adenoma patients with a family history of colorectal cancer from atypical hereditary colorectal families (CRA-H) and sporadic colorectal adenoma patients without a family history of colorectal cancer (CRA-S) was established with 85.0% accuracy. The model distinguishing CRA-H from healthy individuals was established with 90.0% specificity and 86.7% sensitivity. Additionally, five peaks (2202, 5821, 3260, 2480, and 2218) showing differential expression in advanced colorectal adenoma patients with a family history of colorectal cancer were selected. The protein Kininogen 1 (KNG1) was identified in colorectal adenoma patients and validated using Western Blotting. KNG1 may be a biomarker for colorectal adenoma patients with a family history of colorectal cancer.

13.
Sci Total Environ ; 633: 785-795, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29602117

RESUMO

Palm kernel shell (PKS) lignin obtained by enzymatic/mild acid hydrolysis (EMAL) was thoroughly elucidated by FTIR (fourier transform infrared), 13C-1H 2D-NMR (nuclear magnetic resonance), quantitative 31P NMR combined with DFRC (derivatization followed by reductive cleavage), and Py-GC/MS (pyrolysis-gas chromatography/mass spectrometry) with and without TMAH (tetramethylammonium hydroxide). Pyrolysis behavior was then characterized by TG-FTIR-MS (thermo-gravimetric-FTIR-mass spectrometry) and Py-GC/MS. The PKS lignin is demonstrated to be a p-hydroxyphenyl-guaiacyl-syringyl (H-G-S) lignin with abundances of p-hydrobenzoates and low S/G ratio of 0.15. 2D-NMR indicated that the main substructures are ß-O-4-ethers (~85%), and 31P NMR/DFRC quantified the total ß-O-4 content of 2295µmol/g. Py-GC/MS with and without TMAH confirmed that phenol mainly originated from p-hydroxybenzoates units. Thermal-stability, evolution behavior of typical volatiles, and selectivity of phenolic compounds (H-, G-, S-, C-type) during PKS lignin pyrolysis were explored. Relationship between chemical structure and pyrolysis behavior are also obtained. This work will provide a deep insight to the effective utilization of PKS.

14.
Bioresour Technol ; 254: 121-129, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29413912

RESUMO

In attempt to decrease NOX and SO2 emission from thermochemical utilization, three industrial biowastes (penicillin mycelia waste, sewage sludge and peat waste) contained high nitrogen (N) and sulfur (S) were chosen to investigate the denitrification and desulphurization of hydrothermal modification. The results demonstrated that hydrothermal modification destroyed the structure of N- and S-containing components, thereby altering their existed conformations. Inorganic-N (N-IN) and most of amino-N/polyamide-N (N-A) were enriched by liquid phase in the forms of NH4+-N and soluble organic-N (Org-N), respectively; subsequently, Org-N could further decompose to NH4+-N at higher temperature. Residual N in hydrochars was converted from N-A to heterocyclic-N (pyrrolic-N, pyridinic-N and quaternary-N) via hydrolysis and cyclization. Similarly, over 60% of S was remove form biowastes at 240 °C. In solid phase, part of organic-S was altered to thiophenes-S after modified, while the remainder was transformed to inorganic-S; but the variation of inorganic-S in hydrochars strongly affected by its specific species.


Assuntos
Desnitrificação , Esgotos , Hidrólise , Nitrogênio
15.
J Mol Diagn ; 20(2): 225-231, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29277635

RESUMO

Two types of molecular tests have been established to assess the deficiency of the DNA mismatch repair (MMR) system: microsatellite instability (MSI) and immunohistochemical (IHC) analysis. We have developed a reliable method to analyze the MSI status by next-generation sequencing (NGS) based on read-count distribution. A total of 91 patients with primary colorectal cancer were recruited. These patients included 54 cases with loss of expression of any MMR protein in IHC, suggesting deficient MMR (dMMR), and 37 cases of colorectal cancer with staining of all four MMR proteins in IHC, suggesting proficient MMR in the sample after surgery. DNA was extracted from paired tumor-normal tissue for MSI detection by both the ColonCore NGS panel and PCR. The sequencing data from the NGS panel was processed using various MSI detection pipelines for a comparison with the ColonCore panel. Using the MSI-PCR test as the gold standard, MSI-ColonCore achieved 97.9% sensitivity (47 of 48) and 100% specificity (37 of 37) for the detection of MSI status. MSI-ColonCore also showed more efficient and robust performance compared with other NGS-based MSI detection algorithms. The concordance rate was 92.3% between MSI-ColonCore and IHC testing, and 93.4% between MSI-PCR and IHC testing. These results suggest that MSI-ColonCore is a reliable and robust method for MSI status detection by NGS based on read-count distribution.


Assuntos
Neoplasias Colorretais/genética , Enzimas Reparadoras do DNA/análise , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Instabilidade de Microssatélites , Reação em Cadeia da Polimerase/métodos , Neoplasias Encefálicas/genética , Reparo de Erro de Pareamento de DNA , Confiabilidade dos Dados , Formaldeído , Loci Gênicos , Humanos , Imuno-Histoquímica , Síndromes Neoplásicas Hereditárias/genética , Inclusão em Parafina , Sensibilidade e Especificidade
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 189: 190-194, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28820971

RESUMO

We for the first time confirmed that the low concentrations of Ag(I) could induce a silver specific aptamer probe (SAP) from a random coil sequence form to G-quadruplex structure. Thereby, a novel highly sensitive fluorescence strategy for silver(I) assay was established. The designed multifunctional SAP could act as a recognition element for Ag(I) and a signal reporter. The use of such a SAP can ultrasensitively and selectively detect Ag(I), giving a detection limit down to 0.64nM. This is much lower than those reported by related literatures. This strategy has been applied successfully for the detection of Ag(I) in real samples, further proving its reliability. Taken together, the designed SAP is not only a useful recognition and signal probe for silver, but also gives a platform to study the interaction of monovalent cations with DNA.


Assuntos
Aptâmeros de Nucleotídeos/química , Conformação Molecular , Sondas Moleculares/química , Prata/análise , Concentração de Íons de Hidrogênio , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química
17.
Open Biol ; 7(11)2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29118272

RESUMO

Colorectal cancer (CRC) has complex pathological features that defy the linear-additive reasoning prevailing in current biomedicine studies. In pursuing a mechanistic understanding behind such complexity, we constructed a core molecular-cellular interaction network underlying CRC and investigated its nonlinear dynamical properties. The hypothesis and modelling method has been developed previously and tested in various cancer studies. The network dynamics reveal a landscape of several attractive basins corresponding to both normal intestinal phenotype and robust tumour subtypes, identified by their different molecular signatures. Comparison between the modelling results and gene expression profiles from patients collected at the second affiliated hospital of Zhejiang University is presented as validation. The numerical 'driving' experiment suggests that CRC pathogenesis may depend on pathways involved in gastrointestinal track development and molecules associated with mesenchymal lineage differentiation, such as Stat5, BMP, retinoic acid signalling pathways, Runx and Hox transcription families. We show that the multi-faceted response to immune stimulation and therapies, as well as different carcinogenesis and metastasis routes, can be straightforwardly understood and analysed under such a framework.


Assuntos
Neoplasias Colorretais/genética , Modelos Teóricos , Biologia de Sistemas , Estudos de Casos e Controles , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Humanos , Dinâmica não Linear , Processos Estocásticos
18.
Cell Commun Signal ; 15(1): 38, 2017 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-28974231

RESUMO

BACKGROUND: Chloride channel accessory 1 (CLCA1) belongs to the calcium-sensitive chloride conductance protein family, which is mainly expressed in the colon, small intestine and appendix. This study was conducted to investigate the functions and mechanisms of CLCA1 in colorectal cancer (CRC). METHODS: The CLCA1 protein expression level in CRC patients was evaluated by enzyme-linked immunosorbent assay (ELISA), immunohistochemistry (IHC), and western blotting analysis. Using CRISPR/Cas9 technology, CLCA1-upregulated (CLCA1-ACT) and CLCA1-knockout cells (CLCA1-KO), as well as their respective negative controls (CLCA1-ACT-NC and CLCA1-KO-NC), were constructed from the SW620 cell line. Cell growth and metastatic ability were assessed both in vitro and in vivo. The association of CLCA1 with epithelial-mesenchymal transition (EMT) and other signaling pathways was determined by western blotting assays. RESULTS: The expression level of CLCA1 in CRC tissues was significantly decreased compared with that in adjacent normal tissue (P< 0.05). Meanwhile, the serum concentration of CLCA1 in CRC patients was also significantly lower when compared with that of healthy controls (1.48 ± 1.06 ng/mL vs 1.06 ± 0.73 ng/mL, P = 0.0018). In addition, CLCA1 serum concentration and mRNA expression level in CRC tissues were inversely correlated with CRC metastasis and tumor stage. Upregulated CLCA1 suppressed CRC growth and metastasis in vitro and in vivo, whereas inhibition of CLCA1 led to the opposite results. Increased expression levels of CLCA1 could repress Wnt signaling and the EMT process in CRC cells. CONCLUSIONS: Our findings suggest that increased expression levels of CLCA1 can suppress CRC aggressiveness. CLCA1 functions as a tumor suppressor possibly via inhibition of the Wnt/beta-catenin signaling pathway and the EMT process.


Assuntos
Canais de Cloreto/metabolismo , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Via de Sinalização Wnt , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transformação Celular Neoplásica , Transição Epitelial-Mesenquimal , Feminino , Humanos , Masculino , Camundongos
19.
Bioresour Technol ; 245(Pt A): 463-470, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28898845

RESUMO

Hydrothermal treatment (HT) has been proved as a significant pretreatment in decreasing emissions of NOX pollutants from thermochemical utilization of sewage sludge (SS) derived solid fuel. This study aims to investigate the denitrification of HT and the redistribution of nitrogen (N) in different products so as to speculate the comprehensive pathway of N transformation during hydrothermal process. Results found that only 20% of N remained in hydrochar, whereas the rest of N (nearly 80%) was transformed into other phase. A majority of amino-N in SS was enriched in liquid phase in the form of Org-N at first, then further decomposed to NH4+-N. The remaining amino-N converted to pyrrole-N, pyridine-N and quaternary-N as temperature progresses. Meanwhile, amine-N derived from protein-N formed heterocyclic-N in oil phase via Diels-Alder reaction. NH3, the major nitrogenous gas, was dissolved in liquid as NH4+-N immediately after producing, but increased with prolonged reaction time.


Assuntos
Nitrogênio , Esgotos , Temperatura Ambiente
20.
Anal Bioanal Chem ; 409(21): 4951-4958, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28660339

RESUMO

We report a highly sensitive and selective strategy for Cd(II) assay using a singly labeled multifunctional probe consisting of a Cd(II)-specific aptamer (CAP), which acted as a recognition element for Cd(II) and a signal reporter. The presence of Cd(II) can induce the conformational switching of the CAP, accompanied by a change in fluorescence intensity. Thereby, a fluorescence strategy for Cd(II) assay was established. The proposed method has a detection limit of 2.15 nM, which is much lower than the detection limits reported in related literature. This strategy involves only an aptamer probe, and the use of such a G4-based quencher avoids the dual labeling of the CAP with fluorophore/quencher units. It is obviously more convenient and economical than the other aptamer-based biosensors for Cd(II) detection. The mechanism by which Cd(II) induces the CAP to change from a random coil sequence to a stem-loop structure was studied in a series of control experiments. This strategy would be helpful in the design of a sensitive analytical platform for various target assays in environmental and biomedical fields. Graphical Abstract The presence of Cd2+ leads to the conformational change of CAP from a random coil sequence to a stem-loop structure, resulting in a quenching in the fluorescence.

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