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1.
Br J Nutr ; : 1-10, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634368

RESUMO

Malnutrition significantly hampers wound healing processes. This study aimed to compare the effectiveness of the Global Leadership Initiative on Malnutrition (GLIM) and Subjective Global Assessment (SGA) in diagnosing malnutrition and predicting wound healing in patients with diabetic foot ulcers (DFU). GLIM criteria were evaluated for sensitivity (SE), specificity (SP), positive predictive value, negative predictive value and kappa (κ) against SGA as the reference. Modified Poisson regression model and the DeLong test investigated the association between malnutrition and non-healing ulcers over 6 months. This retrospective cohort study included 398 patients with DFU, with a mean age of 66·3 ± 11·9 years. According to SGA and GLIM criteria, malnutrition rates were 50·8 % and 42·7 %, respectively. GLIM criteria showed a SE of 67·3 % (95 % CI 60·4 %, 73·7 %) and SP of 82·7 % (95 % CI 76·6 %, 87·7 %) in identifying malnutrition, with a positive predictive value of 80·0 % and a negative predictive value of 71·1 % (κ = 0·50) compared with SGA. Multivariate analysis demonstrated that malnutrition, as assessed by SGA, was an independent risk factor for non-healing (relative risk (RR) 1·84, 95 % CI 1·45, 2·34), whereas GLIM criteria were associated with poorer ulcer healing in patients with estimated glomerular filtration rate ≥ 60 ml/min/1·73m2 (RR: 1·46, 95 % CI 1·10, 1·94). SGA demonstrated a superior area under the receiver's operating characteristic curve for predicting non-healing compared with GLIM criteria (0·70 (0·65-0·75) v. 0·63 (0·58-0·65), P < 0·01). These findings suggest that both nutritional assessment tools effectively identify patients with DFU at increased risk, with SGA showing superior performance in predicting non-healing ulcers.

2.
J Environ Sci (China) ; 140: 37-45, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38331513

RESUMO

Constructing own oxygen vacancies in the photocatalysts is a very promising method to improve their photocatalytic CO2 reduction activity. However, some catalysts have excellent stabilities, making it difficult for them to construct their own oxygen vacancies. To simplify the above difficulty of stable photocatalysts, constructing extrinsic oxygen vacancies on their surface as a novel idea is proposed. Here, a stable TiO2 nanosheet is chosen as a research object, we uniformly deposited BiOCl quantum dots on their surface via a simple adsorption-deposition method. It is found that BiOCl quantum dots are able to simultaneously self-transform into defective BiOCl with many oxygen vacancies when the photocatalyst is performed photocatalytic CO2 reduction. These extrinsic oxygen vacancies can act as "CO2 and photo-generated electrons reservoirs" to improve CO2 capture and accelerate the separation of photogenerated electrons and holes. For the above reasons, the modified TiO2 showed obvious enhancement of photocatalytic CO2 reduction compared to pristine TiO2 and BiOCl. This work may open a new avenue to broaden the use of oxygen vacancies in the process of photocatalytic CO2 reduction.


Assuntos
Dióxido de Carbono , Pontos Quânticos , Elétrons , Adsorção , Oxigênio
3.
World J Surg Oncol ; 21(1): 78, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36872314

RESUMO

BACKGROUND: The purpose of our study is to investigate the expression level and prognostic value of serum α-hydroxybutyrate dehydrogenase (α-HBDH) in lung cancer (LC) patients. METHOD: LC patients treated in the Department of Oncology, Shaanxi Provincial Cancer Hospital from January 2014 to December 2016 were included in this study, all of whom underwent serological detection of α-HBDH prior to admission, and were enrolled in follow-up 5-year survival. Comparing the differences between high group and normal groups based on α-HBDH and LDH expression via clinicopathological parameters and laboratory data. Univariate and multivariate regression and overall survival (OS) were analyzed to explore whether elevated α-HBDH was an independent risk factor for LC, compared to LDH. RESULTS: Multivariate regression analysis showed that age (P = 0.018), liver metastasis (P = 0.011), α-HBDH (P = 0.015), and neutrophil-to-lymphocyte ratio (NLR) (P = 0.031) were independent prognostic factors affecting OS in LC patients. The overall diagnostic efficacy of α-HBDH (AUC = 0.887) was higher than that of LDH (AUC = 0.709) in the ROC curve. The sensitivity was significantly higher of α-HBDH (sensitivity: 76.06%, specificity: 94.87%) compared with LDH (sensitivity: 49.30%, specificity: 94.87%). The median of OS was more significant in the high-α-HBDH group (6.4 months) than in the normal-α-HBDH group (12.7 months) (P = 0.023). The median of OS was significant in the high-LDH (> 245 U/L) group at 5.8 months and 12.0 months in the normal-LDH (≤ 245 U/L) group (P = 0.068). CONCLUSIONS: Elevated expression of α-HBDH may indicate a poor prognosis of LC patients. It has a higher sensitivity than LDH and can be used as a potential early biomarker and an independent risk factor predicting the prognosis of LC survival.


Assuntos
Neoplasias Hepáticas , Neoplasias Pulmonares , Humanos , Prognóstico , Institutos de Câncer , Hospitalização
4.
Molecules ; 28(11)2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37298876

RESUMO

BiOX (X = Cl, Br, I) families are a kind of new type of photocatalysts, which have attracted the attention of more and more researchers. The suitable band gaps and their convenient tunability via the change of X elements enable BiOX to adapt to many photocatalytic reactions. In addition, because of their characteristics of the unique layered structure and indirect bandgap semiconductor, BiOX exhibits excellent separation efficiency of photogenerated electrons and holes. Therefore, BiOX could usually demonstrate fine activity in many photocatalytic reactions. In this review, we will present the various applications and modification strategies of BiOX in photocatalytic reactions. Finally, based on a good understanding of the above issues, we will propose the future directions and feasibilities of the reasonable design of modification strategies of BiOX to obtain better photocatalytic activity toward various photocatalytic applications.


Assuntos
Elétrons , Pesquisadores , Humanos , Semicondutores
5.
Molecules ; 28(15)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37570663

RESUMO

With the development of the world economy and the rapid advancement of global industrialization, the demand for energy continues to grow. The significant consumption of fossil fuels, such as oil, coal, and natural gas, has led to excessive carbon dioxide emissions, causing global ecological problems. CO2 hydrogenation technology can convert CO2 into high-value chemicals and is considered one of the potential ways to solve the problem of CO2 emissions. Metal/semiconductor catalysts have shown good activity in carbon dioxide hydrogenation reactions and have attracted widespread attention. Therefore, we summarize the recent research on metal/semiconductor catalysts for photocatalytic CO2 hydrogenation from the design of catalysts to the structure of active sites and mechanistic investigations, and the internal mechanism of the enhanced activity is elaborated to give guidance for the design of highly active catalysts. Finally, based on a good understanding of the above issues, this review looks forward to the development of future CO2 hydrogenation catalysts.

6.
Molecules ; 28(10)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37241798

RESUMO

The weak adsorption of CO2 and the fast recombination of photogenerated charges harshly restrain the photocatalytic CO2 reduction efficiency. The simultaneous catalyst design with strong CO2 capture ability and fast charge separation efficiency is challenging. Herein, taking advantage of the metastable characteristic of oxygen vacancy, amorphous defect Bi2O2CO3 (named BOvC) was built on the surface of defect-rich BiOBr (named BOvB) through an in situ surface reconstruction progress, in which the CO32- in solution reacted with the generated Bi(3-x)+ around the oxygen vacancies. The in situ formed BOvC is tightly in contact with the BOvB and can prevent the further destruction of the oxygen vacancy sites essential for CO2 adsorption and visible light utilization. Additionally, the superficial BOvC associated with the internal BOvB forms a typical heterojunction promoting the interface carriers' separation. Finally, the in situ formation of BOvC boosted the BOvB and showed better activity in the photocatalytic reduction of CO2 into CO (three times compared to that of pristine BiOBr). This work provides a comprehensive solution for governing defects chemistry and heterojunction design, as well as gives an in-depth understanding of the function of vacancies in CO2 reduction.

7.
Angew Chem Int Ed Engl ; 62(22): e202218694, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-36972170

RESUMO

To overcome the thermodynamic and kinetic impediments of the Sabatier CO2 methanation reaction, the process must be operated under very high temperature and pressure conditions, to obtain an industrially viable conversion, rate, and selectivity. Herein, we report that these technologically relevant performance metrics have been achieved under much milder conditions using solar rather than thermal energy, where the methanation reaction is enabled by a novel nickel-boron nitride catalyst. In this regard, an in situ generated HOB⋅⋅⋅B surface frustrated Lewis's pair is considered responsible for the high Sabatier conversion 87.68 %, reaction rate 2.03 mol gNi -1 h-1 , and near 100 % selectivity, realized under ambient pressure conditions. This discovery bodes well for an opto-chemical engineering strategy aimed at the development and implementation of a sustainable 'Solar Sabatier' methanation process.

8.
J Clin Lab Anal ; 36(6): e24462, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35522136

RESUMO

PURPOSE: To investigate the expression of heat shock protein 90α (HSP90α) in patients with lung cancer (LC) and the clinical value of HSP90α and other related markers in the diagnosis of LC. METHODS: Of 335 patients enrolled in the study cohort, 175 were screened for LC and 160 were healthy (HC). The plasma levels of HSP90α and related markers (CEA, NSE, CYFRA21-1 and ProGRP) were detected in all individuals in the cohort by enzyme-linked immunosorbent assay (ELISA). Groups were divided according to gender (male/female), age (≤60 years/>60 years), types of LC (small-cell carcinoma, squamous carcinoma and adenocarcinoma), staging (I, II, III and IV) and metastasis (metastasis and non-metastasis) separately. Wilcoxon Mann-Whitney test and Kruskal-Wallis test were used to compare statistical differences between two groups/among the multiple groups for each factor of HSP90α. The r-value and Kappa were used to compare HSP90α with related markers, and the receiver operating curve (ROC) was used to evaluate the efficacy of plasma HSP90α in predicting LC. RESULTS: No statistical difference was found in the plasma level of HSP90α among different age and gender groups (p > 0.05). In the group divided by LC type, staging and metastasis status, there were statistical differences among different groups in HSP90α level (p < 0.05). The levels of HSP90α, CEA, NSE, CYFRA21-1 and ProGRP in LC groups were significantly higher than HC (p < 0.001). R values of HSP90α correlated with other related markers in the diagnosis of LC (p < 0.05). Although HSP90α and other related markers did not fit the satisfactory conformance, in terms of the positive rate of diagnosis, it was statistically differences in the diagnostic positive rate between HSP90α and each marker (p < 0.01). ROC analysis showed that a plasma HSP90α cut-off point of 50.02 ng/ml had an optimal predictive value for LC. CONCLUSIONS: HSP90α has significant clinical value in early screening and diagnosis of LC. The combined application of HSP90α and related markers can improve the positive rate of early diagnosis of LC effectively.


Assuntos
Antígeno Carcinoembrionário , Neoplasias Pulmonares , Antígenos de Neoplasias , Biomarcadores Tumorais , Feminino , Humanos , Queratina-19 , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade
9.
Genes Dev ; 28(17): 1917-28, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25184678

RESUMO

Elevated glycolysis is a common metabolic trait of cancer, but what drives such metabolic reprogramming remains incompletely clear. We report here a novel transcriptional repressor-mediated negative regulation of glycolysis. ZBTB7A, a member of the POK (POZ/BTB and Krüppel) transcription repressor family, directly binds to the promoter and represses the transcription of critical glycolytic genes, including GLUT3, PFKP, and PKM. Analysis of The Cancer Genome Atlas (TCGA) data sets reveals that the ZBTB7A locus is frequently deleted in many human tumors. Significantly, reduced ZBTB7A expression correlates with up-regulation of the glycolytic genes and poor survival in colon cancer patients. Remarkably, while ZBTB7A-deficient tumors progress exceedingly fast, they exhibit an unusually heightened sensitivity to glycolysis inhibition. Our study uncovers a novel tumor suppressor role of ZBTB7A in directly suppressing glycolysis.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Glicólise/genética , Fatores de Transcrição/metabolismo , Animais , Linhagem Celular Tumoral , Células Cultivadas , Feminino , Células HCT116 , Humanos , Células MCF-7 , Camundongos , Neoplasias/genética , Neoplasias/fisiopatologia , Regiões Promotoras Genéticas/genética , Ligação Proteica
10.
Proc Natl Acad Sci U S A ; 115(13): 3452-3457, 2018 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-29540569

RESUMO

Renewable tissues exhibit heightened sensitivity to DNA damage, which is thought to result from a high level of p53. However, cell proliferation in renewable tissues requires p53 down-regulation, creating an apparent discrepancy between the p53 level and elevated sensitivity to DNA damage. Using a combination of genetic mouse models and pharmacologic inhibitors, we demonstrate that it is p53-regulated MDM2 that functions together with MDMX to regulate DNA damage sensitivity by targeting EZH2 (enhancer of zeste homolog 2) for ubiquitination/degradation. As a methyltransferase, EZH2 promotes H3K27me3, and therefore chromatin compaction, to determine sensitivity to DNA damage. We demonstrate that genetic and pharmacologic interference of the association between MDM2 and MDMX stabilizes EZH2, resulting in protection of renewable tissues from radio-/chemotherapy-induced acute injury. In cells with p53 mutation, there are diminished MDM2 levels, and thus accumulation of EZH2, underpinning the resistant phenotype. Our work uncovers an epigenetic mechanism behind tissue sensitivity to DNA damage, carrying important translation implications.


Assuntos
Cromatina/metabolismo , Dano ao DNA , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Epigênese Genética , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas/genética , Proteína Supressora de Tumor p53/genética , Animais , Apoptose , Cromatina/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Camundongos , Camundongos Transgênicos , Ligação Proteica , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Ubiquitinação
11.
Prostate ; 80(12): 986-992, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32557725

RESUMO

BACKGROUND: Focal therapies for prostate cancer (PC) can reduce adverse events and do not lead to androgen-independent progression. Ultrasound could be used for cancer treatments if the repetition frequency is fitted to the purpose. We investigated the possible therapeutic effect of ultrasound irradiation on PC cells. MATERIALS AND METHODS: We irradiated two PC cell lines, androgen-dependent LNCaP and -independent PC-3 with ultrasound (3.0 W/cm2 , 3 MHz, irradiation time rate: 20%) for 2 minutes for 1 day or 3 consecutive days at a repetition frequency of 1, 10, or 100 Hz in vitro. Cell proliferation and apoptosis were determined after irradiation. RESULTS: Cell proliferation of PC-3 was significantly inhibited after 1 day (P < .0001) and 3 days (P < .0001) of 10 Hz ultrasound irradiation, and that of LNCaP after 1 day (P < .0001) and 3 days (P < .0001) of irradiation. LNCaP was more sensitive to ultrasound at both lower and higher cell density but PC-3 was only sensitive at a lower cell density (P < .01). Irradiation with 10 Hz ultrasound-induced significantly more PC-3 apoptotic cells than control (1 day, P = .0137; 3 days, P = .0386) rather than irradiation with 1 Hz. Apoptosis via caspase-3 was induced at 10 Hz in 1-day (P < .05) irradiation in both cell lines. CONCLUSIONS: Ultrasound irradiation with even 1 day of 10 Hz significantly inhibited cell proliferation in both LNCaP and PC-3, especially by the remarkable induction of apoptosis in vitro. Our study indicated that ultrasound irradiation can be a therapeutic option for PC and further studies in vivo will be undertaken.


Assuntos
Neoplasias da Próstata/radioterapia , Terapia por Ultrassom/métodos , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Humanos , Masculino , Células PC-3 , Neoplasias da Próstata/patologia , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/radioterapia
12.
Environ Sci Technol ; 54(23): 15097-15107, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33167623

RESUMO

This study reports on the compositional diversity of organic compounds in metal(loid)-bearing tailings samples from both active and abandoned tailings ponds. Tailings samples were qualitatively analyzed by comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOFMS). In addition, the priority PAHs (16), PAEs (6), and phenols (2) were quantitatively analyzed using gas chromatography-mass spectrometry (GC-MS). We attribute the presence of some of aromatic organics in studied tailings ponds to particular sources. Mineral floatation reagents are likely the major sources of small-ring aromatics in tailings ponds, and products from metallurgical processing and burning of fossil fuels in the mining area or further afield are also possible contributors and might be the main source of large-ring aromatics. We found that tailings ponds abandoned for decades can still have organics concentrations at levels of concern. Large-ring aromatics are generally more toxic than other contaminants, and these were more abundant in abandoned tailings ponds. This suggests that these large-ring organics do not readily decompose or biodegrade into less toxic byproducts, as do volatiles and many other organic compounds. Our aromatic contaminants database provides an important starting point for researchers to investigate and compare similar contaminants that might be also present in other tailings ponds and emphasizes the necessity of considering their transformations over time.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Lagoas , Metais/análise , Mineração , Compostos Orgânicos , Hidrocarbonetos Policíclicos Aromáticos/análise
13.
J Cutan Pathol ; 47(12): 1143-1149, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32829516

RESUMO

BACKGROUND: Pagetoid Spitz nevus is a rare subtype of Spitz nevus usually found on the lower extremities, particularly on the thigh of women. As a rare and under-recognized entity that can be misdiagnosed as melanoma, further characterization of clinical and histopathological features is needed to improve its recognition. METHODS: A retrospective analysis of all melanocytic neoplasms from the thigh diagnosed over a 3-year period. RESULTS: Fifty-five (15.4%) of the 357 melanocytic neoplasms on the thigh were Spitz nevi, the majority of them occurring in women (87.3%). Of the 55 Spitz nevi, 33 (60.0%) were pagetoid Spitz nevi, 14 (25.5%) were Reed nevi, and eight (14.5%) were conventional Spitz nevi. The mean age of patients with pagetoid Spitz nevi was 47.2, the majority being women (84.9%). Pagetoid Spitz nevi were small, with a mean histopathologic diameter of 4 mm, and often junctional (63.6%). Compared to Clark nevi of the thigh, pagetoid Spitz nevi comprised significantly more solitary melanocytes with a greater degree of scatter. CONCLUSIONS: These results suggest that Spitz nevi and, in particular, pagetoid Spitz nevi constitute a significant percentage of nevi on the thigh. Previously reported benign clinical and histopathological features of pagetoid Spitz nevi are confirmed in this study.


Assuntos
Síndrome do Nevo Displásico/patologia , Melanócitos/patologia , Nevo de Células Epitelioides e Fusiformes/patologia , Nevo Pigmentado/patologia , Neoplasias Cutâneas/patologia , Adulto , Idoso , Diagnóstico Diferencial , Erros de Diagnóstico , Síndrome do Nevo Displásico/diagnóstico , Epiderme/patologia , Feminino , Humanos , Masculino , Melanoma/diagnóstico , Melanoma/patologia , Pessoa de Meia-Idade , Nevo de Células Epitelioides e Fusiformes/diagnóstico , Nevo Pigmentado/diagnóstico , Estudos Retrospectivos , Neoplasias Cutâneas/ultraestrutura , Coxa da Perna/patologia
14.
Angew Chem Int Ed Engl ; 58(42): 14850-14854, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31410950

RESUMO

Black liquor, an industrial waste product of papermaking, is primarily used as a low-grade combustible energy source. Despite its high lignin content, the potential utility of black liquor as a feedstock in products manufacturing, remains to be exploited. Demonstrated here in is the use of black liquor as a primary feed-stock for synthesizing graphene quantum dots that exhibit both up-conversion and photoluminescence when excited using visible/near-infrared radiation, thereby enabling the photosensitization of ultraviolet-absorbing TiO2 nanosheets. In addition, these graphene quantum dots can trap photo-generated electrons to realize the effective separation of electron-hole pairs. Together, these two processes facilitate the solar-powered generation of H2 from H2 O, and CO from H2 O-CO2 , using broadband solar radiation.

15.
J Biol Chem ; 291(50): 25937-25949, 2016 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-27777309

RESUMO

Deregulated receptor tyrosine kinase (RTK) signaling is frequently associated with tumorigenesis and therapy resistance, but its underlying mechanisms still need to be elucidated. In this study, we have shown that the RTK human epidermal growth factor receptor 4 (Her4, also known as Erbb4) can inhibit the tumor suppressor p53 by regulating MDMX-mouse double minute 2 homolog (MDM2) complex stability. Upon activation by either overexpression of a constitutively active vector or ligand binding (Neuregulin-1), Her4 was able to stabilize the MDMX-MDM2 complex, resulting in suppression of p53 transcriptional activity, as shown by p53-responsive element-driven luciferase assay and mRNA levels of p53 target genes. Using a phospho-proteomics approach, we functionally identified a novel Her4-induced posttranslational modification on MDMX at Ser-314, a putative phosphorylation site for the CDK4/6 kinase. Remarkably, inhibition of Ser-314 phosphorylation either with Ser-to-Ala substitution or with a specific inhibitor of CDK4/6 kinase blocked Her4-induced stabilization of MDMX-MDM2 and rescued p53 activity. Our study offers insights into the mechanisms of deregulated RTK-induced carcinogenesis and provides the basis for the use of inhibitors targeting RTK-mediated signals for p53 restoration.


Assuntos
Proteínas Nucleares/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptor ErbB-4/metabolismo , Transcrição Gênica , Proteína Supressora de Tumor p53/metabolismo , Animais , Proteínas de Ciclo Celular , Quinase 4 Dependente de Ciclina/genética , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 6 Dependente de Ciclina/genética , Quinase 6 Dependente de Ciclina/metabolismo , Células HEK293 , Humanos , Células MCF-7 , Camundongos , Fosforilação , Proteínas Proto-Oncogênicas c-mdm2/genética , Receptor ErbB-4/genética , Proteína Supressora de Tumor p53/genética
16.
Am J Pathol ; 186(9): 2271-8, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27470713

RESUMO

The conserved RNA-binding protein Musashi1 (MSI1) has been characterized as a stem cell marker, controlling the balance between self-renewal and differentiation and as a key oncogenic factor in numerous solid tumors, including glioblastoma. To explore the potential use of MSI1 targeting in therapy, we studied MSI1 in the context of radiation sensitivity. Knockdown of MSI1 led to a decrease in cell survival and an increase in DNA damage compared to control in cells treated with ionizing radiation. We subsequently examined mechanisms of double-strand break repair and found that loss of MSI1 reduces the frequency of nonhomologous end-joining. This phenomenon could be attributed to the decreased expression of DNA-protein kinase catalytic subunit, which we have previously identified as a target of MSI1. Collectively, our results suggest a role for MSI1 in double-strand break repair and that its inhibition may enhance the effect of radiotherapy.


Assuntos
Reparo do DNA/fisiologia , Glioblastoma/patologia , Proteínas do Tecido Nervoso/metabolismo , Polinucleotídeo 5'-Hidroxiquinase/metabolismo , Proteínas de Ligação a RNA/metabolismo , Tolerância a Radiação/fisiologia , Domínio Catalítico/fisiologia , Linhagem Celular Tumoral , Ensaio Cometa , Quebras de DNA de Cadeia Dupla/efeitos da radiação , DNA Catalítico , Imunofluorescência , Humanos , Immunoblotting , Reação em Cadeia da Polimerase
17.
Environ Monit Assess ; 189(1): 25, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28000122

RESUMO

Artisanal zinc smelting activities, which had been widely applied in Bijie City, Guizhou Province, southwestern of China, can pollute surrounding farmlands. In the present study, 177 farmland topsoil samples of Bijie City were collected and 11 potentially toxic trace elements (PTEs), namely Pb, Zn, Cu, Ni, Co, Mn, Cr, V, Hg, As, and Cd were tested to characterize the concentrations, sources, and ecological risks. Mean concentrations of these PTEs in soils were (mg/kg) as follows: Pb (127), Zn (379), Cu (93.1), Ni (54.6), Co (26.2), Mn (1095), Cr (133), V (206), Hg (0.15), As (16.2), and Cd (3.08). Pb, Zn, and Cd had coefficients of variation greater than 100% and showed a high uneven distribution and spatial variability in the study area. Correlation coefficient analysis and principal component analysis (PCA) were used to quantify potential pollution sources. Results showed that Cu, Ni, Co, Mn, and V came from natural sources, whereas Pb, Zn, Hg, As, and Cd came from anthropogenic pollution sources. Geoaccumulation index and potential ecological risk indices were employed to study the pollution degree of PTEs, which revealed that Pb and Cd shared the greatest contamination and would pose serious ecological risks to the surrounding environment. The results of this study could help the local government managers to establish pollution control strategies and to secure food safety.


Assuntos
Monitoramento Ambiental/métodos , Metais Pesados/análise , Poluentes do Solo/análise , Oligoelementos/análise , China , Cidades , Ecologia , Poluição Ambiental/análise , Medição de Risco , Solo/química , Zinco/análise
18.
Int J Cancer ; 138(6): 1328-36, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26044706

RESUMO

The RNA-guided nuclease CRISPR-Cas9 (clustered regularly interspaced short palindromic repeats-CRISPR associated nuclease 9) and its variants such as nickase Cas9, dead Cas9, guide RNA scaffolds and RNA-targeting Cas9 are convenient and versatile platforms for site-specific genome editing and epigenome modulation. They are easy-to-use, simple-to-design and capable of targeting multiple loci simultaneously. Given that cancer develops from cumulative genetic and epigenetic alterations, CRISPR-Cas9 and its variants (hereafter referred to as CRISPR-Cas9 systems) hold extensive application potentials in cancer modeling and therapy. To date, they have already been applied to model oncogenic mutations in cell lines (e.g., Choi and Meyerson, Nat Commun 2014;5:3728) and in adult animals (e.g., Xue et al., Nature 2014;514:380-4), as well as to combat cancer by disabling oncogenic viruses (e.g., Hu et al., Biomed Res Int 2014;2014:612823) or by manipulating cancer genome (e.g., Liu et al., Nat Commun 2014;5:5393). Given the importance of epigenome and transcriptome in tumourigenesis, manipulation of cancer epigenome and transcriptome for cancer modeling and therapy is a promising area in the future. Whereas (epi)genetic modifications of cancer microenvironment with CRISPR-Cas9 systems for therapeutic purposes represent another promising area in cancer research. Herein, we introduce the functions and mechanisms of CRISPR-Cas9 systems in genome editing and epigenome modulation, retrospect their applications in cancer modelling and therapy, discuss limitations and possible solutions and propose future directions, in hope of providing concise and enlightening information for readers interested in this area.


Assuntos
Sistemas CRISPR-Cas , Neoplasias/genética , Neoplasias/metabolismo , Animais , Epigênese Genética , Humanos , Mutação , Neoplasias/terapia , Edição de RNA , RNA Guia de Cinetoplastídeos/genética
19.
J Biol Chem ; 289(8): 5340-7, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24391088

RESUMO

Radiotherapy is the current frontline cancer treatment, but the resulting severe side effects often pose a significant threat to cancer patients, raising a pressing need for the development of effective strategies for radiotherapy protection. We exploited the distinct metabolic characteristics between normal and malignant cells for a metabolic mechanism of normal tissue protection. We showed that low doses of arsenic induce HIF-1α, which activates a metabolic shift from oxidative phosphorylation to glycolysis, resulting in increased cellular resistance to radiation. Of importance is that low-dose arsenic-induced HIF-1α requires functional p53, limiting the glycolytic shift to normal cells. Using tumor-bearing mice, we provide proof of principle for selective normal tissue protection against radiation injury.


Assuntos
Arsênio/farmacologia , Metabolismo/efeitos dos fármacos , Protetores contra Radiação/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Glicólise/efeitos dos fármacos , Glicólise/efeitos da radiação , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Metabolismo/efeitos da radiação , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , NF-kappa B/metabolismo , Tolerância a Radiação/efeitos dos fármacos , Tolerância a Radiação/efeitos da radiação , Irradiação Corporal Total
20.
Water Sci Technol ; 72(6): 983-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26360759

RESUMO

The excessive discharge of Pb(II) into the environment has increasingly aroused great concern. Adsorption is considered as the most effective method for heavy metal removal. Chinese walnut shell activated carbon (CWSAC) was used as an adsorbent for the removal of Pb(II) from aqueous solution. Batch experiments were conducted by varying contact time, temperature, pH, adsorbent dose and initial Pb(II) concentration. Adsorption equilibrium was established within 150 min. Although temperature effect was insignificant, the Pb(II) adsorption was strongly pH dependent and the maximum removal was observed at pH 5.5. The Pb(II) removal efficiency increased with increasing CWSAC dosage up to 2.0 g/L and reached a maximum of 94.12%. Langmuir and Freundlich adsorption isotherms were employed to fit the adsorption data. The results suggested that the equilibrium data could be well described by the Langmuir isotherm model, with a maximum adsorption capacity of 81.96 mg/g. Adsorption kinetics data were fitted by pseudo-first- and pseudo-second-order models. The result indicated that the pseudo-first-order model best describes the adsorption kinetic data. In summary, CWSAC could be a promising material for the removal of Pb(II) from wastewater.


Assuntos
Carvão Vegetal/química , Juglans/química , Chumbo/química , Poluentes Químicos da Água/química , Adsorção , Cinética , Temperatura , Purificação da Água
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