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1.
Cancer Commun (Lond) ; 2024 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-38734931

RESUMEN

BACKGROUND: Metabolic reprograming and immune escape are two hallmarks of cancer. However, how metabolic disorders drive immune escape in head and neck squamous cell carcinoma (HNSCC) remains unclear. Therefore, the aim of the present study was to investigate the metabolic landscape of HNSCC and its mechanism of driving immune escape. METHODS: Analysis of paired tumor tissues and adjacent normal tissues from 69 HNSCC patients was performed using liquid/gas chromatography-mass spectrometry and RNA-sequencing. The tumor-promoting function of kynurenine (Kyn) was explored in vitro and in vivo. The downstream target of Kyn was investigated in CD8+ T cells. The regulation of CD8+ T cells was investigated after Siglec-15 overexpression in vivo. An engineering nanoparticle was established to deliver Siglec-15 small interfering RNA (siS15), and its association with immunotherapy response were investigated. The association between Siglec-15 and CD8+ programmed cell death 1 (PD-1)+ T cells was analyzed in a HNSCC patient cohort. RESULTS: A total of 178 metabolites showed significant dysregulation in HNSCC, including carbohydrates, lipids and lipid-like molecules, and amino acids. Among these, amino acid metabolism was the most significantly altered, especially Kyn, which promoted tumor proliferation and metastasis. In addition, most immune checkpoint molecules were upregulated in Kyn-high patients based on RNA-sequencing. Furthermore, tumor-derived Kyn was transferred into CD8+ T cells and induced T cell functional exhaustion, and blocking Kyn transporters restored its killing activity. Accroding to the results, mechanistically, Kyn transcriptionally regulated the expression of Siglec-15 via aryl hydrocarbon receptor (AhR), and overexpression of Siglec-15 promoted immune escape by suppressing T cell infiltration and activation. Targeting AhR in vivo reduced Kyn-mediated Siglec-15 expression and promoted intratumoral CD8+ T cell infiltration and killing capacity. Finally, a NH2-modified mesoporous silica nanoparticle was designed to deliver siS15, which restored CD8+ T cell function status and enhanced anti-PD-1 efficacy in tumor-bearing immunocompetent mice. Clinically, Siglec-15 was positively correlated with AhR expression and CD8+PD-1+ T cell infiltration in HNSCC tissues. CONCLUSIONS: The findings describe the metabolic landscape of HNSCC comprehensively and reveal that the Kyn/Siglec-15 axis may be a novel potential immunometabolism mechanism, providing a promising therapeutic strategy for cancers.

2.
Chin Med ; 19(1): 58, 2024 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-38584284

RESUMEN

BACKGROUND: Danggui Sini decoction (DSD), a traditional Chinese medicine formula, has the function of nourishing blood, warming meridians, and unblocking collaterals. Our clinical and animal studies had shown that DSD can effectively protect against oxaliplatin (OXA)-induced peripheral neuropathy (OIPN), but the detailed mechanisms remain uncertain. Multiple studies have confirmed that gut microbiota plays a crucial role in the development of OIPN. In this study, the potential mechanism of protective effect of DSD against OIPN by regulating gut microbiota was investigated. METHODS: The neuroprotective effects of DSD against OIPN were examined on a rat model of OIPN by determining mechanical allodynia, biological features of dorsal root ganglia (DRG) as well as proinflammatory indicators. Gut microbiota dysbiosis was characterized using 16S rDNA gene sequencing and metabolism disorders were evaluated using untargeted and targeted metabolomics. Moreover the gut microbiota mediated mechanisms were validated by antibiotic intervention and fecal microbiota transplantation. RESULTS: DSD treatment significantly alleviated OIPN symptoms by relieving mechanical allodynia, preserving DRG integrity and reducing proinflammatory indicators lipopolysaccharide (LPS), IL-6 and TNF-α. Besides, DSD restored OXA induced intestinal barrier disruption, gut microbiota dysbiosis as well as systemic metabolic disorders. Correlation analysis revealed that DSD increased bacterial genera such as Faecalibaculum, Allobaculum, Dubosiella and Rhodospirillales_unclassified were closely associated with neuroinflammation related metabolites, including positively with short-chain fatty acids (SCFAs) and sphingomyelin (d18:1/16:0), and negatively with pi-methylimidazoleacetic acid, L-glutamine and homovanillic acid. Meanwhile, antibiotic intervention apparently relieved OIPN symptoms. Furthermore, fecal microbiota transplantation further confirmed the mediated effects of gut microbiota. CONCLUSION: DSD alleviates OIPN by regulating gut microbiota and potentially relieving neuroinflammation related metabolic disorder.

3.
Eur J Med Res ; 28(1): 585, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38082369

RESUMEN

AIM AND OBJECTIVE: To compare the clinical effect of reconstruction of internal and lateral column periosteal hinge-assisted treatment with Kirschner wire and internal fixation with Kirschner wire in the treatment of multidirectional unstable supracondylar fractures of humerus in children. METHODS: A retrospective cohort study was conducted to analyze the clinical data of 48 patients (31 male, 17 female; mean age: 6.7 ± 2.4 years old) with multidirectionally unstable supracondylar fractures of the humerus treated in our Hospital from August 2020 to August 2022. Twenty-five cases were treated with Kirschner wire reconstruction of the internal and lateral column periosteal hinge assisted by closed reduction and Kirschner wire internal fixation (study group). Twenty-three cases were treated with closed reduction and Kirschner wire internal fixation (control group). The operation time, intraoperative fluoroscopy times, percentage of patients who underwent open reduction after failure of closed reduction, fracture healing time, Baumann angle (BA), shaft-condylar angle (SCA), range of motion (ROM), and Flynn score of elbow at the last follow-up were compared between two groups. Complications such as infection and irritation of Kirschner wire tail were observed in two groups 2 months after the operation. RESULTS: All patients were followed up for 10-22 months ([13.85 ± 2.89] months). The average operation time of the control group was 82.1 min, which was significantly longer than that of the study group 32.3 min (P < 0.05). The number of intraoperative fluoroscopy (29.4 ± 9.2) in the control group was significantly higher than that in the study group (15.2 ± 6.3) (P < 0.05). The incision rate of the control group was 17% while that of the study group was 0 (P < 0.05). According to Flynn score, the excellent and good rate of the elbow joint in the control group was 86.9% (20/23). The excellent and good rate of the elbow joint in the study group was 92.0% (23/25) (P > 0.05). There was no significant difference in fracture healing time, BA, SCA, and ROM between the two groups (P > 0.05). No infection or Kirschner wire tail irritation occurred in the two groups during the 2-month follow-up. CONCLUSION: Reconstruction of internal and lateral periosteal hinges with Kirscher wire has similar effects to closed reduction and Kirschner wire fixation in the treatment of multidirectionally unstable supracondylar fractures of the humerus in children, but it can shorten the operation time and reduce intraoperative fluoroscopy times and incision rate.


Asunto(s)
Hilos Ortopédicos , Fracturas del Húmero , Niño , Humanos , Masculino , Femenino , Preescolar , Fracturas del Húmero/cirugía , Estudios Retrospectivos , Húmero/cirugía , Fijación Interna de Fracturas , Resultado del Tratamiento
4.
Neural Regen Res ; 17(8): 1711-1716, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35017418

RESUMEN

Myeloperoxidase is an important inflammatory factor in the myeloid system, primarily expressed in neutrophils and microglia. Myeloperoxidase and its active products participate in the occurrence and development of hemorrhagic and ischemic stroke, including damage to the blood-brain barrier and brain. As a specific inflammatory marker, myeloperoxidase can be used in the evaluation of vascular disease occurrence and development in stroke, and a large amount of experimental and clinical data has indicated that the inhibition or lack of myeloperoxidase has positive impacts on stroke prognosis. Many studies have also shown that there is a correlation between the overexpression of myeloperoxidase and the risk of stroke. The occurrence of stroke not only refers to the first occurrence but also includes recurrence. Therefore, myeloperoxidase is significant for the clinical evaluation and prognosis of stroke. This paper reviews the potential role played by myeloperoxidase in the development of vascular injury and secondary brain injury after stroke and explores the effects of inhibiting myeloperoxidase on stroke prognosis. This paper also analyzes the significance of myeloperoxidase etiology in the occurrence and development of stroke and discusses whether myeloperoxidase can be used as a target for the treatment and prediction of stroke.

5.
Front Microbiol ; 11: 1423, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32733400

RESUMEN

Pseudomonas aeruginosa is an opportunistic pathogen commonly infecting immunocompromised patients with diseases like cystic fibrosis (CF) and cancers and has high rates of recurrence and mortality. The treatment efficacy can be significantly worsened by the multidrug resistance (MDR) of P. aeruginosa, and there is increasing evidence showing that it is easy for this pathogen to develop MDR. Here, we identified a gene cluster, pltZ-pltIJKNOP, which was originally assumed to be involved in the biosynthesis of an antimicrobial pyoluteorin, significantly contributing to the antibiotic resistance of P. aeruginosa ATCC 27853. Moreover, the TetR family regulator PltZ binds to a semi-palindromic sequence in the promoter region of the pltIJKNOP operon and recognizes the antimicrobial 2,4-diacetylphloroglucinol (2,4-DAPG), which in turn induces the expression of the pltIJKNOP operon. Using quantitative proteomics method, it was indicated that the regulator PltZ also plays an important role in maintaining metabolic hemostasis by regulating the transporting systems of amino acids, glucose, metal ions, and bacteriocins.

6.
Cancer Sci ; 111(4): 1303-1313, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31994271

RESUMEN

The survival benefit from docetaxel, cisplatin and 5-fluorouracil (TPF) induction chemotherapy in oral squamous cell carcinoma (OSCC) patients is not satisfactory. Previously, we identified that stathmin, a microtubule-destabilizing protein, is overexpressed in OSCC. Here, we further investigated its role as a biomarker that impacts on OSCC chemosensitivity. We analyzed the predictive value of stathmin on TPF induction chemotherapy and its impact on OSCC cell chemosensitivity. Then, we further investigated the therapeutic effects of the combination therapy of TPF chemotherapy and PI3K-AKT-mTOR inhibitors in vitro and in vivo. We found that OSCC patients with low stathmin expression benefited from TPF induction chemotherapy, while OSCC patients with high stathmin expression could not benefit from TPF induction chemotherapy. Stathmin overexpression promoted cellular proliferation and decreased OSCC cell sensitivity to TPF treatment. In addition, inhibition of the PI3K-AKT-mTOR signaling pathway decreased stathmin expression and phosphorylation. The combination therapy of TPF chemotherapy and PI3K-AKT-mTOR inhibitors exhibited a potent antitumor effect both in vitro and in vivo. Therefore, stathmin can be used as a predictive biomarker for TPF induction chemotherapy and a combination therapy regimen based on stathmin expression might improve the survival of OSCC patients.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Carcinoma de Células Escamosas/tratamiento farmacológico , Neoplasias de la Boca/tratamiento farmacológico , Estatmina/genética , Anciano , Animales , Biomarcadores de Tumor/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cisplatino/administración & dosificación , Supervivencia sin Enfermedad , Docetaxel/administración & dosificación , Femenino , Fluorouracilo/administración & dosificación , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Xenoinjertos , Humanos , Masculino , Ratones , Persona de Mediana Edad , Neoplasias de la Boca/genética , Neoplasias de la Boca/patología , Proteína Oncogénica v-akt/genética , Fosfatidilinositol 3-Quinasas/genética , Medicina de Precisión , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/genética , Taxoides/administración & dosificación
7.
Am J Cancer Res ; 8(11): 2296-2310, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30555745

RESUMEN

ANRIL (CDKN2B antisense RNA 1, CDKN2B-AS1) is involved in the progression of various cancers. However, its role in head and neck squamous cell carcinoma (HNSCC) remains unclear. In this study, we found that ANRIL expression was upregulated in HNSCC and correlated with tumor progression. Further functional analysis showed that knockdown of ANRIL significantly inhibited proliferation in vivo and in vitro. ANRIL functioned as a ceRNA (competing endogenous RNAs) for miR-125a-3p and upregulated FGFR1 (fibroblast growth factor receptor-1), which could promote tumor growth. Moreover, we confirmed that ANRIL promoted HNSCC activity via FGFR1 with a FGFR1 inhibitor in vivo and in vitro. Thus, it could be concluded that ANRIL promoted the progression of HNSCC via miR-125a-3p/FGFR1/MAPK signaling, which might provide a new target for the diagnosis and treatment of HNSCC.

8.
Int J Med Sci ; 15(4): 385-394, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29511374

RESUMEN

A TIE2 mutation causing arginine-to-tryptophan substitution at residue 849 (TIE2-R849W) is commonly identified in heredofamilial venous malformation. However, there is no in vivo model to confirm the pathogenic role of TIE2-R849W. Humanized TIE2-R849W plasmid was constructed via PCR-mediated site-directed mutagenesis. After transcription and micro-injection, TIE2-R849W significantly induces multiple malformations in zebrafish: caudal vein plexus (CVP) defect, eye abnormalities, forebrain formation perturbations, and mandibular malformation. Histologically, these phenotypes accompany aphakia, confused retina plexiform layer, abnormal mandibular cartilage, ectopic myelencephalon proliferation and aberrant location of neurogliocytes. According to qRT-PCR, except for high expression of egfl7, the other CVP-related genes cd146, nr2f1a, and s1pr1 are not significantly different from control. TIE2-R849W also induced upregulation of the wnt signaling pathway. Gene array in vitro shows that under the effect of TIE2-R849W, consistent with high expression of pik3 and foxo1, high levels of egfl7, wnt9a, lrp5 and dkk1 were partly confirmed. This in vivo model directly identifies the venous-related pathogenic role of TIE2-R849W. Under up-regulation of TIE2-R849W, egfl7 could be considered a potential reason for venous defects. Moreover, the wnt pathway may perform an important role as a key trigger for head multi-malformations.


Asunto(s)
Malformaciones Vasculares/genética , Venas/patología , Proteínas de Pez Cebra/genética , Animales , Animales Modificados Genéticamente , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/genética , Humanos , Mutación , Fosforilación , Receptor TIE-2/genética , Malformaciones Vasculares/patología , Venas/metabolismo , Pez Cebra/genética
9.
J Exp Clin Cancer Res ; 36(1): 109, 2017 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-28806997

RESUMEN

BACKGROUND: The aim of this study was to investigate the oncogenic function and regulatory mechanism of stathmin in oral squamous cell carcinoma (OSCC). METHODS: Two-dimensional electrophoresis and liquid chromatography-tandem mass chromatography were applied to screen differentiated proteins during carcinogenesis in OSCC. Cell Counting Kit-8 (CCK-8) assays, colony formation, migration, flow cytometry, immunofluorescence and a xenograft model were used to detect the function of stathmin. The correlation between stathmin and p53 expression was analyzed using immunohistochemistry. Mutant/wild type p53 plasmids and small interfering RNA were used to examine the regulation of stathmin. Chromatin immunoprecipitation assays and luciferase assays were performed to detect the transcriptional activation of stathmin by p53. RESULTS: Overexpression of stathmin was screened and confirmed in OSCC patients and cell lines. Silencing expression of stathmin inhibited proliferation, colony formation and migration and promoted apoptosis. Poly ADP ribose polymerase (PARP) and cyclin-dependent kinase 1 (cdc2) were activated after silencing the expression of stathmin. Suppression of tumorigenicity was also confirmed in vivo. Mutant p53 transcriptionally activated the expression of stathmin in HN6 and HN13 cancer cells, but not in HN30 cells harboring wild type p53. CONCLUSIONS: These results suggest that stathmin acts as an oncogene and is transcriptionally regulated by mutant p53, but not by wild-type p53. Stathmin could be a potential anti-tumor therapeutic target in OSCC.


Asunto(s)
Carcinoma de Células Escamosas/genética , Neoplasias de la Boca/genética , Estatmina/genética , Proteína p53 Supresora de Tumor/genética , Animales , Biomarcadores de Tumor/genética , Carcinogénesis/genética , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Neoplasias de la Boca/patología , Proteínas Mutantes/genética , Estatmina/antagonistas & inhibidores , Ensayos Antitumor por Modelo de Xenoinjerto
10.
J Craniomaxillofac Surg ; 44(10): 1725-1732, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27591090

RESUMEN

PURPOSE: The stathmin/oncoprotein 18 (STMN1) is overexpressed in various human cancers. The aim of our study was to investigate its clinical significance and interaction with p53 in oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: Stathmin expression was assessed by Oncomine, Gene Expression Omnibus (GEO) database, western blotting, and reverse transcription polymerase chain reaction. We investigated the relationship between stathmin expression and clinical characteristics among 109 OSCC patients by immunohistochemical staining. The prognosis factors were analyzed using univariate and multivariate analysis. Immunoprecipitation assay and The Cancer Genome Atlas (TCGA) analysis were used to detect the relationship between mutant p53 and stathmin. RESULTS: Stathmin was overexpressed in OSCC. In immunohistochemical analysis, high stathmin expression correlated with gender (P = 0.040), T stage (P = 0.015), TNM stage (P = 0.045), and pathological differentiation (P = 0.000). We found a correlation between the stathmin expression and overall survival (P = 0.027). Multivariate analysis suggested only lymph node metastasis (P = 0.007) and stathmin expression (P = 0.013) as independent prognostic factors. There was interaction between stathmin and p53 in OSCC cell lines with mutant p53 through immunoprecipitation assay. CONCLUSION: These results suggest that overexpression of stathmin could contribute to cancer progression/prognosis, and that interaction between p53 and stathmin may contribute to the gain-of-function of p53.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico , Neoplasias de la Boca/diagnóstico , Estatmina/análisis , Proteína p53 Supresora de Tumor/metabolismo , Biomarcadores de Tumor , Western Blotting , Carcinoma de Células Escamosas/química , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/química , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/patología , Pronóstico , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estatmina/metabolismo
11.
Oncotarget ; 7(2): 2113-22, 2016 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-26544895

RESUMEN

PURPOSE: To investigate the mutation status of growth differentiation factor 15 (GDF15) in patients with oral squamous cell carcinoma (OSCC), as well as the prognostic value of missense GDF15 mutations. PATIENTS AND METHODS: Formalin-fixed paraffin-embedded biopsy samples from 46 OSCC patients were involved in this study. GDF15 and TP53 mutations were sequenced using the Ion Torrent Personal Genome Machine, GDF15 protein expression was detected using immunohistochemistry. Torrent Suite Software v.3.6, Integrative Genomics Viewer; v.2.3, statistical software SPSS18.0 for Windows were used for analysis. All hypothesis-generating tests were two-sided at a significance level of 0.05. RESULTS: Twenty-nine GDF15 mutations were identified in 19 out of 46 patients (41.3%), including eighteen missense mutations, two nonsense mutations and nine synonymous mutations. The patients with missense GDF15 mutations had poorer prognostic outcomes than those with wild-type GDF15, including overall survival (P = 0.035), disease-free survival (P = 0.032), locoregional recurrence-free survival (P = 0.015), and distant metastasis-free survival (P = 0.070). Missense GDF15mutations was an independent increased risk factor of overall survival (HR = 5.993, 95% CI:1.856-19.346, P = 0.003), disease-free survival (HR = 3.764, 95% CI:1.295-10.945, P = 0.015), locoregional recurrence-free survival (HR = 4.555, 95% CI:1.494-13.889, P = 0.008), and distant metastasis-free survival (HR = 4.420, 95% CI:1.145-13.433, P = 0.009). CONCLUSIONS: Patients with missense GDF15 mutations have significantly poorer outcomes than those with wild-type GDF15, missense GDF15 mutations could be used as an independent increased risk factor of poor prognosis in OSCC patients.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma de Células Escamosas/genética , Factor 15 de Diferenciación de Crecimiento/genética , Neoplasias de la Boca/genética , Mutación Missense/genética , Recurrencia Local de Neoplasia/genética , Proteína p53 Supresora de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/secundario , Femenino , Estudios de Seguimiento , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Técnicas para Inmunoenzimas , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/patología , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Pronóstico , Tasa de Supervivencia
12.
Exp Cell Res ; 339(2): 289-99, 2015 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-26589264

RESUMEN

Pirfenidone is an orally bioavailable synthetic compound with therapeutic potential for idiopathic pulmonary fibrosis. It is thought to act through antioxidant and anti-fibrotic pathways. Pirfenidone inhibits proliferation and/or myofibroblast differentiation of a wide range of cell types, however, little studies have analyzed the effect of pirfenidone on the mesenchymal stem cells, which play an important role on the origin of myofibroblasts. We recently found that pirfenidone had anti-proliferative activity via G1 phase arrest and cell division cycle 7 (Cdc7) kinase expression decrease in transforming growth factor-ß1 (TGF-ß1)-stimulated murine mesenchymal stem C3H10T1/2 cells. Pirfenidone also had inhibiting effect on the migration and α-SMA expression. Moreover, in this study we showed for the first time that Cdc7 inhibitor XL413 enhanced the anti-fibrotic activity of pirfenidone via depressed the expression of Smad2/4 proteins, and also prevented the nuclear accumulation and translocation of Smad2 protein. In conclusion, we demonstrated that pirfenidone inhibited proliferation, migration and differentiation of TGF-ß1-stimulated C3H10T1/2 cells, which could be enhanced by Cdc7 inhibitor XL413, via Smad2/4. Combination with pirfenidone and XL413 might provide a potential candidate for the treatment of TGF-ß1 associated fibrosis. It needs in vivo studies to further validate its therapeutic function and safety in the future.


Asunto(s)
Proteínas de Ciclo Celular/antagonistas & inhibidores , Fibrosis/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Piridonas/farmacología , Pirimidinonas/farmacología , Proteína Smad2/metabolismo , Proteína Smad4/metabolismo , Factor de Crecimiento Transformador beta1/farmacología , Ciclo Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Humanos , Relación Estructura-Actividad
13.
Huan Jing Ke Xue ; 36(6): 2116-21, 2015 Jun.
Artículo en Chino | MEDLINE | ID: mdl-26387315

RESUMEN

The paper used the method of iron copper catalyst reduction to degrade low concentrations of bromochloracetonitrile (BCAN) to lighten the damage to human being, which is a kind of disinfection by-products (DBPs) produced during the chlorination process of drinking water. The removal efficiency of BCAN and its influencing factors were investigated. The mechanism of degradation and kinetics were also explored. The results indicated that iron copper had a greater degradation ability towards BCAN, and the degradation rate of iron copper (mass ratio of 10:1) was 1.5 times that of the zero-valent iron. The removal of BCAN increased obviously with the increase of Fe/Cu dosage. When the initial concentration was set at 20 microg x L(-1), after a reaction time of 150 min, removal of BCAN was improved from 51.1% to 89.5% with the increase of iron copper (mass ratio of 10:1) dosage from 5 g x L(-1) to 10 g x L(-1). The temperature also had great impact on BCAN removal and the removal increased with the increase of temperature. However, BCAN removal did not change a lot with the variation of the initial concentration of BCAN when it was at a low level. The BCAN degradation by iron copper catalytic-reduction followed the first-order kinetics model.


Asunto(s)
Acetonitrilos/análisis , Agua Potable/química , Contaminantes Químicos del Agua/análisis , Catálisis , Cobre , Hierro , Cinética , Purificación del Agua
14.
J Oral Pathol Med ; 44(3): 193-200, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25047743

RESUMEN

BACKGROUND: Glutathione S transferase pi (GSTP1) is a member of phase II detoxification enzymes as a major regulator of cell signaling in response to stress, hypoxia, growth factors, and other stimuli. The clinical role of GSTP1 in cancer is still unclear. The aim of this study was to investigate the serum GSTP1 level in patients with oral squamous cell carcinoma (OSCC) and the GSTP1 expression in tissue samples from patients with OSCC and OSCC lines. METHODS: One hundred and sixty-six patients with OSCC and 120 normal persons were used to screen potential serum peptide biomarkers using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Serum GSTP1 concentration was detected in 18 patients with OSCC and 18 normal persons using ELISA. Immunohistochemistry was used to detect GSTP1 expression in tissue samples from twenty-eight OSCC patients. Western blot and real-time PCR were used to detect GSTP1 expression in nine OSCC lines. RESULTS: Decreased GSTP1 concentration was found in the patients with OSCC compared with the normal persons by MALDI-TOF-MS, which was then confirmed by ELISA (P = 0.019). Decreased GSTP1 mRNA level and protein expression were also found in the OSCC lines. Decreased GSTP1 expression was found correlating with pathological differentiation grade in the tissue samples from OSCC patients, a lower GSTP1 expression indicating a poorer pathological differentiation grade (P = 0.041). CONCLUSIONS: These results suggest that decreased GSTP1 expression in patients with OSCC and a lower GSTP1 expression indicating a poorer pathological differentiation grade in OSCC tissue samples.


Asunto(s)
Carcinoma de Células Escamosas/patología , Gutatión-S-Transferasa pi/sangre , Neoplasias de la Boca/patología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/sangre , Carcinoma de Células Escamosas/sangre , Carcinoma de Células Escamosas/enzimología , Línea Celular , Línea Celular Tumoral , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunohistoquímica , Nanopartículas de Magnetita , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/sangre , Neoplasias de la Boca/enzimología , Clasificación del Tumor , Estadificación de Neoplasias , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(8): 2227-30, 2013 Aug.
Artículo en Chino | MEDLINE | ID: mdl-24159882

RESUMEN

In the present paper, the high-temperature phase change of pure tobermorite was investigated by TGA/DSC, X-ray diffraction and infrared spectroscopy (IR) respectively. The DSC results showed that four interlayer water molecules were lost when they were heated at 300 degrees C. As the temperature increased to 724 degrees C, Si-O-H bonds were cleaved and dehydroxylation occurred. The XRD results showed that many diffraction peaks o f tobermorite disappeared and the crystal structure was broken and collapsed. Then tobermorite tends to be disordered and amorphous. When the calcination temperature increased to 861 degrees C, the disordered structure recombined to wollastonite, and the crystal structure became ordered and stable. Finally, the structure completely transformed to 2M-wollastonite at 1 000 degrees C. It should include the process of high-temperature phase change of tobermorite: tobermorite --> dehydration tobermorite --> dehydroxylation tobermorite --> wollastonite.

16.
Molecules ; 15(10): 7188-96, 2010 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-20956883

RESUMEN

Sulfonated (SO(3)H-bearing) activated carbon (AC-SO(3)H) was synthesized by an aryl diazonium salt reduction process. The obtained material had a SO(3)H density of 0.64 mmol·g-1 and a specific surface area of 602 m2·g-1. The catalytic properties of AC-SO(3)H were compared with that of two commercial solid acid catalysts, Nafion NR50 and Amberlyst-15. In a 10-h esterification reaction of acetic acid with ethanol, the acid conversion with AC-SO(3)H (78%) was lower than that of Amberlyst-15 (86%), which could be attributed to the fact that the SO(3)H density of the sulfonated carbon was lower than that of Amberlyst-15 (4.60 mmol·g-1). However, AC-SO(3)H exhibited comparable and even much higher catalytic activities than the commercial catalysts in the esterification of aliphatic acids with longer carbon chains such as hexanoic acid and decanoic acid, which may be due to the large specific surface area and mesoporous structures of the activated carbon. The disadvantage of AC-SO(3)H is the leaching of SO(3)H group during the reactions.


Asunto(s)
Carbono/química , Oxidación-Reducción , Ácidos Sulfónicos/química , Catálisis , Estirenos/química , Difracción de Rayos X
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