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1.
Chemosphere ; 349: 140847, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38043614

RESUMO

Nonradical species with great resistance to interference have shown great advantages in complex wastewater treatment. Herein, a novel system constructed by biodegradable tetrakis-(4-carboxyphenyl)-porphyrinatoiron(III) (FeIII-TCPP) and peroxymonosulfate (PMS) was proposed for facile decontamination. Nonradical pathway is observed in FeIII-TCPP/PMS, where 1O2 and high-valent iron-oxo species play dominant roles. The genres and valence of high-valent iron-oxo species, including iron(IV)-oxo porphyrin radical-cationic species [OFeIV-TCPP•+] and iron(IV)-hydroxide species [FeIV-TCPP(OH)], are ascertained, along with their generation mechanism. The axial ligand on the iron axial site affects the ground spin state of FeIII-TCPP, further influencing the thermodynamic reaction pathway of active species. With trace catalyst in micromoles, FeIII-TCPP exhibits high efficiency by degrading bisphenol S (BPS) completely within 5 min, while Co2+/PMS can only achieve a maximum of 26.2% under identical condition. Beneficial from nonradical pathways, FeIII-TCPP/PMS demonstrates a wide pH range of 3-10 and exhibits minimal sensitivity to interference of concomitant materials. BPS is primarily eliminated through ß-scission and hydroxylation. Specifically, 1O2 electrophilically attacks the C-S bond of BPS, while high-valent iron-oxo species interacts with BPS through an oxygen-bound mechanism. This study provides novel insights into efficient activation of PMS by iron porphyrin, enabling the removal of refractory pollutants through nonradical pathway.


Assuntos
Poluentes Ambientais , Porfirinas , Compostos Férricos/química , Peróxidos/química , Ferro , Oxigênio
2.
Chemosphere ; 309(Pt 1): 136744, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36209859

RESUMO

Developing efficient catalysts with low cost and environmental friendliness for peroxymonosulfate (PMS) activation attracts broad interest. In this study, TiO2-hemin was prepared by immobilizing hemin on TiO2 using a ball milling method, demonstrating 126.9-fold enhanced catalytic degradation efficiency compared with unsupported hemin in the PMS activation system, with 92.9% of 2,4,6-trichlorophenol (2,4,6-TCP) removed in 10 min. The superior performance is attributed to the strong interaction between TiO2 and hemin, which induces the redistribution of the electron density of hemin molecules. In the TiO2-hemin/PMS system, sulfate radicals (SO4•-), hydroxyl radicals (•OH), singlet oxygen (1O2), and superoxide radicals (O2•-) were identified, which only played a minor role in the elimination of 2,4,6-TCP. Instead, high-valent iron-oxo species were proposed and identified as the primary active species. This study provides a facile strategy to enhance the activity of the biomimetic catalyst and offers insight into the catalytic mechanism of iron porphyrin with PMS activation.


Assuntos
Ferro , Porfirinas , Oxigênio Singlete , Superóxidos , Hemina , Oxirredução , Sulfatos
3.
Front Mol Biosci ; 8: 620683, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968980

RESUMO

Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) has been shown to play a pivotal role in the regulation of mitochondrial biogenesis in diseases. Resveratrol (RSV), a natural polyphenolic reagent, has powerful antioxidant properties and the ability to scavenge mitochondrial reactive oxygen species (ROS) in a variety of central nervous system diseases. However, the underlying molecular mechanisms of RSV on mitochondrial biogenesis in early brain injury (EBI) following subarachnoid hemorrhage (SAH) remain poorly understood. This study aimed to explore the potential neuroprotective effects of RSV on mitochondrial biogenesis and function by activation of the PGC-1α signaling pathway in a prechiasmatic cistern SAH model. PGC-1α expression and related mitochondrial biogenesis were detected. Amounts of nuclear respiratory factor 1 (NRF1) and mitochondrial transcription factor A (TFAM) were determined to evaluate the extent of mitochondrial biogenesis. Increased PGC-1α and mitochondrial biogenesis after SAH were observed in the temporal cortex. Resveratrol increased the expression of PGC-1α, NRF1, and TFAM, and promoted PGC-1α nuclear translocation. Moreover, RSV could scavenge excess ROS, increase the activity of superoxide dismutase (SOD), enhance the potential of mitochondrial membrane and ATP levels, reduce the number of mitochondrial DNA copy, and decrease the level of malondialdehyde (MDA). RSV significantly ameliorated the release of apoptosis-related cytokines, namely P53, cleaved caspase-3, cytochrome c, and BAX, leading to the amelioration of neuronal apoptosis, brain edema, and neurological impairment 24 h after SAH. These results indicate that resveratrol promotes mitochondrial biogenesis and function by activation of the PGC-1α signaling pathway in EBI following SAH.

4.
Turk Neurosurg ; 24(2): 190-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24831359

RESUMO

AIM: This study reports our preliminary experiences in performing detachable micro-coils embolization for refractory traumatic carotid cavernous fistulas (TCCFs) and evaluates its efficacy and safety. MATERIAL AND METHODS: Fifteen consecutive patients with TCCFs treated with detachable micro-coils after initial failure of detachable balloons embolization are presented. RESULTS: The fistulas were successfully occluded along with preservation of internal carotid artery (ICA) in 14 cases. However, the fistula and ICA were finally occluded with balloons in one case. The micro-coil got unraveled in one case, and the unraveled part had to be pulled into and fixed to the external carotid artery. All patients have undergone clinical and angiography follows up for a median duration of 22 months (range, 14 to 48 months). The clinical symptoms and signs related to fistulas such as proptosis, bruit, chemosis and headache gradually decreased after endovascular treatment in 14 cases, and only one case recurred after 2 weeks. CONCLUSION: Micro-coils embolization is a safe and reliable strategy in refractory TCCFs that could not be managed by using detachable balloons. It may not be possible to densely pack the cavernous sinus, and subtotal packing also effectively occludes the fistula and alleviates the patient's symptoms.


Assuntos
Artéria Carótida Interna/cirurgia , Fístula Carótido-Cavernosa/terapia , Seio Cavernoso/cirurgia , Embolização Terapêutica , Adolescente , Adulto , Idoso , Lesões das Artérias Carótidas/terapia , Angiografia Cerebral/métodos , Embolização Terapêutica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Resultado do Tratamento , Adulto Jovem
5.
Pak J Med Sci ; 30(2): 432-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24772157

RESUMO

Objective : Disabled-2 (Dab2) is an important endocytic adaptor which plays an inhibition role in cancer cell growth. The objective of this study was to systematically review expressions of Dab2 in human cancers. Methods : Eligible studies about Dab2 in human cancers were retrieved from databases of PubMed, Embase, Web of Science. Odds Ratios (ORs) with 95% confidence intervals (CIs) were calculated using Review Manager 5.0 software and statistical analyses were performed by the SPSS 13.0 software. Results : Fourteen case-control studies with a total of 689 human tumor tissues, 332 control tissues and 32 cancer cell lines were included in the meta-analysis study. The results indicated loss expressions of Dab2 were observed in 74.9% and 46.9% in human malignant cancer tissues and cancer cell lines, respectively. The ratio of Dab2 promotor hypermethylation is 34.54% in cancer tissues which Dab2 expression are lost, but none in the control tissues or cells by Methylation-specific PCR (MSP). Conclusions : The expressions of Dab2 are frequently lost in human malignant cancer tissues, and promotor hypermethylation of Dab2 are common in human malignant cancer tissues, which is an important factor for the loss expression of Dab2 in human cancers tissues.

6.
Neurol India ; 62(1): 57-61, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24608456

RESUMO

AIMS: Disabled-2 (Dab2) is frequently down-regulated in several types of cancers. We examined the expression level of Dab2 in human meningiomas and meningioma cells, aimed to investigate its role in the oncogenesis and development of meningiomas. MATERIALS AND METHODS: Western blot analysis was employed to detect Dab2 expression in 90 fresh tissues of meningiomas, 10 leptomeninges and two kinds of human malignant meningioma cell lines. Independent samples t-test, analysis of variance, Pearson Chi-square test and likelihood ratio test were used to analyze the expression level of Dab2 and its relations to clinic-pathological characteristics of meningiomas. RESULTS: Dab2 was significantly down-regulated in classic meningiomas than the atypical or anaplastic meningiomas. The reduced or loss of expression of Dab2 were significantly correlated with the lower classification of meningiomas and negatively correlated with the invasive ability of adjacent tissues. Furthermore, it was reduced or lost in malignant meningioma cell lines (IOMM-Lee and KT21-MG1). The lower classification of meningiomas correlated with previous comorbidities; not with the gender, age of patients and smoking. CONCLUSIONS: Dab2 is expressed at variable level in meningiomas with different grade of malignancy and probably plays a pivotal role in the early stage of oncogenesis of malignant meningiomas.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias Meníngeas/genética , Meningioma/genética , Proteínas Supressoras de Tumor/genética , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Adulto , Idoso , Proteínas Reguladoras de Apoptose , Linhagem Celular Tumoral , Regulação para Baixo/genética , Feminino , Humanos , Masculino , Neoplasias Meníngeas/classificação , Neoplasias Meníngeas/patologia , Meningioma/classificação , Meningioma/patologia , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica/genética , Proteínas Supressoras de Tumor/antagonistas & inibidores , Proteínas Supressoras de Tumor/biossíntese
7.
Korean J Radiol ; 14(3): 497-500, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23690720

RESUMO

This report concerns a 4-month-old infant with progressive prominent and redness of his left eye since birth. This report concerns a 4-month-old infant with progressive prominent redness of his left eye since birth. Angiography revealed a congenital pial arteriovenous fistula between the temporal branch of the left posterior cerebral artery and left cavernous sinus through the sphenoparietal sinus, a condition not reported in the literature. The fistula was successfully occluded with two micro-coils by vertebrobasilar approach.


Assuntos
Fístula Arteriovenosa/diagnóstico , Seio Cavernoso , Malformações Arteriovenosas Intracranianas/diagnóstico , Fístula Arteriovenosa/terapia , Seio Cavernoso/diagnóstico por imagem , Embolização Terapêutica/métodos , Humanos , Lactente , Malformações Arteriovenosas Intracranianas/terapia , Imageamento por Ressonância Magnética , Masculino , Artéria Cerebral Posterior , Radiografia , Lobo Temporal/irrigação sanguínea
8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 37(2): 212-4, 225, 2006 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-16608077

RESUMO

OBJECTIVE: To test the expression of Cathepsin B (CB) protease in gliomas and to investigate its correlation with the malignance and angiogenesis of gliomas. METHODS: Immunochemistry technique of strept actividin-biotin complex (SABC) was used to identify the CB expression and to measure the microvessel density (MVD) in 47 gliomas samples and 5 normal human brain tissues from patients with spontaneous cerebral hemorrhage. RESULTS: No CB expression was detected in the normal brain tissues. The expression levels of CB in astrocytoma, anaplastoma, and glioblastoma were 30% (6/20 weak positive), 86.7% (3/15 weak and, 10/15 moderate positive), and 100.0% (2/12 moderate and 10/12 strong positive), respectively. The malignances of gliomas increased with CB expression (r=0. 77, P<0.05). The MVD also increased with CB expression (r= 0.56, P<0. 05), with an average of 15.57 +/- 8.52, 22.50 +/- 14.42, 39.85 +/- 8.75 and 49.90 +/- 11.30 for the negative, weak, moderate, and strong CB expression gliomas respectively. CONCLUSION: CB expression is positively correlated with the malignances and angiogenesis of gliomas. CB expression could be one of the indicators for the degree of malignances and invasion of gliomas.


Assuntos
Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Catepsina B/biossíntese , Glioma/metabolismo , Neovascularização Patológica , Adulto , Idoso , Astrocitoma/metabolismo , Biomarcadores Tumorais/metabolismo , Catepsina B/genética , Feminino , Glioblastoma/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/biossíntese , RNA Mensageiro/genética
9.
J Neurooncol ; 71(1): 3-7, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15719267

RESUMO

Samples were taken from supratentorial gliomas border and normal brain autopsy which were divided into four groups, these including eight cases normal brain tissues, 30 cases of astrocytomas, 25 cases of anaplastic astrocytomas and 22 cases of glioblastomas. Cathepin B (CB) expression and microvessel density (MVD) were determined with immunohistochemical studies. Staining results of CB was scored according to the percentage of positive cells, graded as negative (-), weak (+), moderate (++), and strong (+ + +). MVD was analyzed by Weidner's revised technique. CB positive staining was negative in eight cases of normal brain tissue. Only 9 out of 30 cases of astrocytomas showed a low percentage of positive cells that were stained in a light, diffuse cytoplasmic pattern (score +). Twenty-two out of 35 cases of anaplastic astrocytomas showed positive light, granular staining pattern, it including five samples (score +), and 17 samples (score + +). In contrast, all 22 cases of glioblastomas were stained all, and it was present in a course, granular staining pattern with an intensity of score (+ +) of two sample, and score (+ + +) of 20 samples. Positive staining tumor cells were found in extracellular matrix (ECM), basement membrane (BM), and the endothelial cells of blood vessels were also positive stained. Along with elevating glioma grade, CB expression and MVD value were both increased. Therefore, it showed MVD value was positive correlated with expression of CB. It highly suggested that CB and angiogenesis plays an important role in glioma progression.


Assuntos
Astrocitoma/irrigação sanguínea , Astrocitoma/enzimologia , Catepsina B/metabolismo , Neoplasias Supratentoriais/irrigação sanguínea , Neoplasias Supratentoriais/enzimologia , Adolescente , Adulto , Idoso , Astrocitoma/patologia , Endotélio Vascular/patologia , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Glioblastoma/irrigação sanguínea , Glioblastoma/enzimologia , Glioblastoma/patologia , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Índice de Gravidade de Doença , Neoplasias Supratentoriais/patologia
10.
Zhong Yao Cai ; 28(11): 1009-12, 2005 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-16514890

RESUMO

OBJECTIVE: To investigate the effects of Extract of Ginkgo biloba on ICAM-1 and mRNA expression in rats with cerebral injury, and discuss its protective mechanism. METHODS: The acute closed brain injury model was set up in rats according Feeney's method. Seventy-two rats were randomly divided into four groups. The levels of ICAM-1 expression were observed using immunohistochemistry and computerized imaging technique and the expression of mRNA were studied using RT-PCR techniques. RESULTS: ICAM-1 positive cells located in the transitional zone between the necrotic core and normal cortex. ICAM-1 protein and mRNA expression began to show 6 hours after cerebral injury, peaked at 24 hours. As compared with the model group, ICAM-1 and mRNA expression was significantly reduced in the group EGb (P < 0.01). CONCLUSION: EGb can markedly reduce the injury of nerve cell in the transitional zone, alleviate rat cerebral injury, and decrease ICAM-1 and mRNA expression and neutrophils infiltration. The protection may be related with its inhibition on ICAM-1 and mRNA expression.


Assuntos
Lesões Encefálicas/metabolismo , Ginkgo biloba/química , Molécula 1 de Adesão Intercelular/biossíntese , Fármacos Neuroprotetores/farmacologia , Plantas Medicinais/química , Animais , Encéfalo/metabolismo , Feminino , Molécula 1 de Adesão Intercelular/genética , Folhas de Planta/química , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley
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