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1.
Sci Rep ; 11(1): 85, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420105

RESUMO

In this work, CeO2 nanosheets decorated with Ag2O and AgBr are successfully fabricated via a simple sediment-precipitation method. The as-prepared ternary Ag2O/AgBr-CeO2 composite with double Z-scheme construction was analyzed by various analytical techniques. Ag nanoparticles (NPs) used as the electron medium could reduce the recombination of photoelectrons and holes, thus leading to the improvement of photocatalytic performance of these catalysts. Due to the unique structure and composite advantages, the optimal Ag2O/AgBr-CeO2 photocatalysts exhibit the superior tetracycline (TC) degradation efficiency of 93.23% and favorable stability with near-initial capacity under visible light irradiation. This ternary Z-scheme structure materials will be the well-promising photocatalysts or the purification of antibiotic wastewater.

2.
Medicine (Baltimore) ; 96(30): e6838, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28746171

RESUMO

BACKGROUND: The Acute Physiology and Chronic Health Evaluation II (APACHE II) score is used to determine disease severity and predict outcomes in critically ill patients. However, the prognostic significance of APACHE after acute paraquat (PQ) poisoning remains unclear. The meta-analysis was aimed to study the value of APACHE II in predicting mortality in PQ-exposed Chinese and Korean patients. METHODS: Databases that included PubMed, Embase, Cochrane Library, and the Chinese National Knowledge Infrastructure were searched through August 2016. Studies using APACHE II to predict mortality in PQ-poisoned patients were selected. The odds ratio and weighted mean difference (WMD) were used to pool binary and continuous data. Additionally, we aggregated sensitivity, specificity, and other measures of accuracy. Statistical analyses were made using the Stata V.13.0 software. RESULTS: This study included 29 studies, and 25 studies evaluated APACHE II scores on admission. Pooled data showed that survivors had significantly lower total scores than nonsurvivors (WMD = -7.29, and I = 98.2%, both P <.05). The pooled sensitivity of an APACHE II score ≥5 for predicting mortality was 75% and the pooled specificity was 86%. The positive likelihood ratio (PLR) was 5.3 and the negative likelihood ratio (NLR) was 0.29. The pooled sensitivity of an APACHE II score ≥10 for predicting mortality was 88% and the pooled specificity was 84%. The pooled PLR and NLR was 5.5 and 0.15, respectively. CONCLUSION: This study showed PQ-poisoned nonsurvivors had significantly higher APACHE II score than did survivors. APACHE II scores satisfactorily predicted mortality.


Assuntos
APACHE , Herbicidas/intoxicação , Paraquat/intoxicação , China , Humanos , Mortalidade , Prognóstico , República da Coreia
3.
PLoS One ; 11(1): e0146301, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26731011

RESUMO

Many studies aimed at investigating bone repair have been conducted through animal models in recent years. However, limitations do exist in these models due to varying regeneration potential among different animal species. Even using the same animal, big differences exist in the size of critical size defects (CSD) involving the same region. This study aimed to investigate the standardization of radial bone defect models in rabbits and further establish more reliable CSD data. A total of 40 6-month-old New Zealand white rabbits of clean grade totaling 80 radial bones were prepared for bone defect models, according to the principle of randomization. Five different sizes (1.0, 1.2, 1.4, 1.7 and 2.0 cm) of complete periosteal defects were introduced under anesthesia. At 12 weeks postoperatively, with the gradual increase in defect size, the grades of bone growth were significantly decreased in all 5 groups. X-ray, CT scans and H&E staining of the 1.4, 1.7, and 2.0-cm groups showed lower grades of bone growth than that of the 1.0 and 1.2-cm groups respectively (P < 0.05). Using rabbit radial defect model involving 6-month-old healthy New Zealand white rabbits, this study indicates that in order to be critical sized, defects must be greater than 1.4 cm.


Assuntos
Regeneração Óssea/fisiologia , Rádio (Anatomia)/crescimento & desenvolvimento , Animais , Modelos Animais , Coelhos
4.
Cell Physiol Biochem ; 37(2): 592-602, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26343984

RESUMO

BACKGROUND/AIMS: Benzene is a toxic chemical whose leukemogenic effects have been studied for decades. The mechanisms of benzene-induced toxicity and leukemogenicity are not fully understood, although the involvement of several pathways has been suggested, including oxidative stress, DNA damage, cell cycle regulation and programmed cell death. In the present study, we investigated the effect of hydroquinone (HQ), a major benzene metabolite, on the viability of bone marrow derived mesenchymal stem cells (BMSCs) and explored the underlying mechanisms. METHODS: First, we study the the effect of HQ on BMSCs cell viability, apoptosis and the expressions of MDR1 and NF-κB. Then we investigate the MDR1 on cell viability and cell apoptosis for BMSCs under HQ treatment. Finally, we studied the impact of nuclear factor κB (NF-κB) on the expression of MDR1. RESULTS: Our results showed that HQ decreased cell viability and promoted cell apoptosis of BMSCs, as determined by the MTT assay and flow cytometry. Western blotting and quantitative PCR showed that HQ downregulated the expression of the MDR1 gene by inhibiting the activation and nuclear translocation of the transcription factor NF-κB. Overexpression of MDR1 attenuated the inhibitory effect of HQ on cell viability in BMSC. CONCLUSION: The results of the present study suggest the involvement of the multidrug resistance membrane transporter MDR1 and the NF-κB pathway in the cytotoxicity of benzene and its metabolites. Further studies are necessary to clarify the role of the pathways involved and the crosstalk between them in mediating the effects of HQ in bone marrow progenitor cells.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Hidroquinonas/toxicidade , Células-Tronco Mesenquimais/efeitos dos fármacos , Animais , Apoptose , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica , Células-Tronco Mesenquimais/citologia , NF-kappa B/metabolismo , Coelhos , Transdução de Sinais
5.
Int J Mol Med ; 34(6): 1565-72, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25318625

RESUMO

Alterations in the expression of microRNAs (miRNAs or miRS) have been implicated in the pathogenesis of the majority of human malignancies, and the dysregulation of microRNA-144 (miR-144) has been associated with several diseases. However, the potential involvement of miR-144 in osteosarcoma, a common malignant bone tumor in children and adolescents with a high risk of relapse and metastasis, has not yet been fully investigated. In the present study, we examined the expression and roles of miRNAs in osteosarcoma as potential diagnostic markers and therapeutic targets, and we focused on miR-144 due to its known involvement in osteogenesis. We demonstrate that miR-144 is downregulated in osteosarcoma cell lines and primary human osteosarcoma tissue samples and that its ectopic expression inhibits osteosarcoma cell proliferation and invasion. We identified TAGLN as a downstream target of miR-144 and demonstrated that its expression is upregulated in osteosarcoma cell lines and tumor tissue and is inversely correlated with miR-144 expression. Our results indicate that miR-144 may regulate osteosarcoma cell proliferation and invasion by downregulating its target gene, TAGLN, suggesting that miR-144 may be a potential therapeutic target for the treatment of osteosarcoma.


Assuntos
Neoplasias Ósseas/genética , Proliferação de Células/genética , MicroRNAs/genética , Proteínas dos Microfilamentos/genética , Proteínas Musculares/genética , Osteossarcoma/genética , Regiões 3' não Traduzidas/genética , Animais , Sequência de Bases , Neoplasias Ósseas/patologia , Linhagem Celular , Linhagem Celular Tumoral , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Osteossarcoma/patologia , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
6.
J Occup Environ Med ; 56(10): e92-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25285841

RESUMO

OBJECTIVE: To evaluate the impact of exposure to low concentrations of benzene on the platelet-associated antibodies and platelet parameters. METHODS: We carried out an analysis on 121 benzene-exposed workers and 110 healthy workers whose blood samples were collected and the levels of platelet-associated antibodies and platelet parameters were assessed. Benzene emissions were monitored over 5 years. RESULTS: Large-platelet cell ratios (P-LCR), platelet distribution width (PDW), and mean platelet volume (MPV) were significantly higher in benzene-exposed participants than in control participants. In participants who smoke cigarettes or drank alcohol, P-LCR, PDW, and MPV were more significantly elevated in the benzene-exposed group than in nonsmokers and nondrinkers. Platelet-associated immunoglobulin (PAIg) levels in benzene-exposed participants were higher than those in the control group, and PAIgA and PAIgM levels correlated with cumulative benzene exposure. CONCLUSIONS: Exposure to low concentrations of benzene can induce changes in PAIg levels and platelet parameters.


Assuntos
Anticorpos/sangue , Antígenos de Plaquetas Humanas/sangue , Benzeno/toxicidade , Plaquetas/efeitos dos fármacos , Exposição Ocupacional/efeitos adversos , Adulto , China , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Inquéritos e Questionários
7.
Artigo em Chinês | MEDLINE | ID: mdl-25182814

RESUMO

OBJECTIVE: To explore the effects of acrylonitrile on T lymphocyte subsets, expression of toll-like receptor 4 and related cytokines in rats. METHODS: Sixty-four Sprague-Dawley rats were randomly divided into 4 female groups and 4 male groups, and there were 8 rats in each group. Rats in each group were respectively given a single dose of 0, 5, 10 and 20 mg/kg acrylonitrile by gavage, once a day, 5 days a week, for 13 weeks. Blood and spleen T lymphocyte subsets was detected by flow cytometry, the mRNA expression of TLR4, IL-1ß and TNF-α was analyzed by real-time quantitative PCR, the protein expression of TLR4 was evaluated by Western blot. RESULTS: Compared with control group, the percentages of blood CD3, CD4 T cells in 20 mg/kg female group and CD4/CD8 ratio in 5, 10 and 20 mg/kg female groups was significantly decreased, CD8 T cells in 20 mg/kg group was significantly increased (P < 0.05 or P < 0.01), blood CD3 T cells in 5 mg/kg male group, CD4 T cells and CD4/CD8 ratio in 20 mg/kg male groups were lower than that of control group, CD8 T cells in 20 mg/kg make group was significantly in oreased (P < 0.05 or P < 0.01). Spleen CD4, CD8 T lymphocyte percentages and CD4/CD8 ratio in 20 mg/kg female group decreased significantly, CD8 T cells in 20 mg/kg male group was significantly increased (P < 0.05 or P < 0.01), spleen CD3, CD4, CD8 T cells in 20 mg/kg male group and CD4/CD8 ratio in 10, 20 mg/kg male groups was also significantly decreased, CD3 T cells in 20 mg/kg and CD8 T cells in 10, 20 mg/kg male groups were significantly increased (P < 0.05 or P < 0.01) (TLR4 mRNA was lower expressed in 5, 10 and 20 mg/kg male groups and 10 mg/kg female group (P < 0.05 or P < 0.01), and TLR4 protein in 5 mg/kg female group and 20 mg/kg male group was significantly lower than control group (P < 0.05). The expression level of IL-1ß mRNA was significantly decreased in 5, 10 and 20 mg/kg female group and 5, 10 mg/kg male group (P < 0.05 or P < 0.01), TNF-α mRNA was lower expressed in 10, 20 mg/kg female groups and 5, 10 mg/kg male groups (P < 0.01). CONCLUSION: Acrylonitrile may lead to the changes of CD3, CD4, CD8 T lymphocyte percentages and CD4/CD8 ratio in rat blood and spleen, and also significantly effected the expression level of TLR4 mRNA and protein together with the secretion of IL-1ß, TNF-α. This may cause effects on the cellular immune function.


Assuntos
Acrilonitrila/toxicidade , Subpopulações de Linfócitos T/imunologia , Receptor 4 Toll-Like/metabolismo , Animais , Feminino , Interleucina-1beta/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Subpopulações de Linfócitos T/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
8.
Artigo em Chinês | MEDLINE | ID: mdl-24148956

RESUMO

OBJECTIVE: To analyze the clinical features and diagnostic points of occupational acute dimethylformamide (DMF) poisoning and to explore the mechanism of occupational acute DMF poisoning. METHODS: A comprehensive analysis was performed on the clinical data of 16 cases of occupational acute DMF poisoning, including symptoms, signs, and laboratory testing results. RESULTS: The main clinical features of occupational acute DMF poisoning were digestive system impairments, especially abdominalgia. Hemorrhagic gastroenteritis was not found by gastroscopy. There was no significant correlation between the degree of abdominalgia and alanine aminotransferase level (r(s) = 0.109, P>0.05). CONCLUSION: Abdominalgia is recommended to be one of the reference indices for the diagnosis and degrading of occupational acute DMF poisoning, The mechanism of DMF poisoning remains unclear but it is considered to be related to methyl isocyanate, the intermediate product of DMF metabolism.


Assuntos
Dimetilformamida/intoxicação , Exposição Ocupacional , Solventes/intoxicação , Dor Abdominal/induzido quimicamente , Alanina Transaminase/metabolismo , Humanos
11.
Artigo em Chinês | MEDLINE | ID: mdl-23433151

RESUMO

OBJECTIVE: To investigate the effects of benzene poisoning on the expression of multidrug resistance 1 (MDR1) gene and P-glycoprotein (P-gp) in the bone marrow mononuclear cells (BMMNCs) of C57BL/6 mice. METHODS: C57BL/6 mice were randomly divided into control group (n = 24), low-dose group (n = 24), medium-dose group (n = 24), and high-dose group (n = 24) to receive corn oil, 25 mg/kg benzene, 50 mg/kg benzene, or 100 mg/kg benzene by gavage, once daily, 5 days/weeks, for 4 weeks. The mice were sacrificed on day 12, 26, or 29 of poisoning. Peripheral blood routine test was performed; real-time quantitative PCR was used to measure the MDR1 gene expression in BMMNCs; Western blot was used to measure the P-gp expression in BMMNCs. RESULTS: On day 12, the red blood cell count and hemoglobin level in the high-dose group were significantly lower than those in the control group, low-dose group, and medium-dose group (P < 0.01 or P < 0.05). On day 26, the white blood cell count in the high-dose group was significantly lower than those in the control group, low-dose group, and medium-dose group (P < 0.01 or P < 0.05). At each time point, the mRNA expression of MDR1 gene in the low-dose group, medium-dose group, and high-dose group was significantly lower than that in the control group (P < 0.01). On day 26, the P-gp expression in the high-dose group was significantly lower than those in the control group, low-dose group, and medium-dose group, and the P-gp expression in the medium-dose group was significantly lower than that in the low-dose group (P < 0.01 or P < 0.05). On day 29, the P-gp expression in the low-dose group, medium-dose group, and high-dose group was significantly lower than that in the control group (P < 0.05). CONCLUSION: Benzene poisoning can affect the expression of MDR1 gene and P-gp, which may be one of the mechanisms of benzene hematotoxicity.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Benzeno/toxicidade , Células da Medula Óssea/efeitos dos fármacos , Resistência a Múltiplos Medicamentos/genética , Monócitos/efeitos dos fármacos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/citologia , Monócitos/metabolismo
12.
Artigo em Chinês | MEDLINE | ID: mdl-21619790

RESUMO

OBJECTIVE: To explore the effects of MDR1 C3435T on the peripheral white blood cell counts in workers exposed to benzene. METHODS: One hundred and twenty-one benzene-exposed workers and 110 healthy controls without benzene exposure were enrolled in this study. White blood cell counts influenced by the polymorphism of MDR1 gene were analyzed. RESULTS: The frequency of MDR1 3435 C/C, C/T, T/T in healthy controls was 37.27%, 46.36%, 16.37%, respectively, and it was 38.84%, 41.33%, 19.83% in the benzene-exposed workers, respectively. The frequency of the MDR1 gene was also not significantly different between benzene exposed workers and controls. Subjects exposed to benzene with MDR1 3435 mutation genotype (T/T) had the significantly lower WBC [(5.46 ± 1.51) × 10(9)/L] than those carrying wild type (C/C) and heterozygous (C/T), whose WBC were (6.08 ± 1.28) × 10(9)/L (P = 0.044). CONCLUSION: P-glycoprotein encoded by MDR1 gene may be implicated into the hematotoxicity of benzene. Subjects carrying MDR1 3435 T/T genotype may have a higher risk of benzene poisoning.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Benzeno/efeitos adversos , Exposição Ocupacional , Polimorfismo de Nucleotídeo Único , Subfamília B de Transportador de Cassetes de Ligação de ATP , Adulto , Grupos Controle , Feminino , Genótipo , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade
13.
Artigo em Chinês | MEDLINE | ID: mdl-21619805

RESUMO

OBJECTIVE: Using high resolution melting (HRM) to analysis MDR1 C3435T in people exposed to benzene. METHODS: Restriction fragment length polymorphism (RFLP) was utilized to detect the polymorphism of MDR1 3435 in 121 benzene-exposed workers, and the results were compared with the HRM in 10% samples and were confirmed with direct sequencing for six people in them. RESULTS: By direct sequencing, consistent results of benzene-exposed workers with RFLP or HRM were got. The new high resolution melting curve analysis is more efficient, more convenient, and cheaper than RFLP. CONCLUSION: High-resolution melting analysis provides a valid approach to efficiently detect DNA genetic diagnosis, which is suitable for detect susceptible genes in occupational surveillance.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Benzeno , Técnicas de Genotipagem/métodos , Exposição Ocupacional , Polimorfismo de Nucleotídeo Único , Subfamília B de Transportador de Cassetes de Ligação de ATP , Genótipo , Heterozigoto , Humanos , Polimorfismo de Fragmento de Restrição
15.
Artigo em Chinês | MEDLINE | ID: mdl-16105461

RESUMO

OBJECTIVE: To explore the mechanism of male reproductive toxicity induced by acrylonitrile (ACN). METHODS: Male Sprague-Dawley rats were daily administrated ACN by intraperitoneal injection 5 times a week for 13 weeks at the dose of 0, 7.5, 15.0 and 30.0 mg/kg body weight, respectively. The rats were sacrificed and testes were removed at the end of 4, 8, 13 or 15 weeks, respectively. The activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and glutathione S-transferase (GST) and the levels of glutathione (GSH) and malonaldehyde (MDA) were detected in testes. RESULTS: Following ACN treatment of 4 weeks, the levels of GSH in ACN 15.0 mg/kg and 30.0 mg/kg group were (7.44 +/- 0.77) mg/g pro and (6.95 +/- 0.77) mg/g pro respectively, and the activity of GSH-Px was (70.89 +/- 4.01) U/mg pro in 30.0 mg/kg group, all of which were significantly higher than the control group (P < 0.05, P < 0.01). After 8 weeks, the levels of GSH decreased to (2.50 +/- 0.94) mg/g pro in ACN 30.0 mg/kg group (P < 0.01); the activities of SOD increased to (102.08 +/- 16.08) NU/mg pro and (113.30 +/- 17.20) NU/mg pro in ACN 15.0 mg/kg and 30.0 mg/kg group (P < 0.01). After 13 weeks, the levels of GSH declined in ACN 15.0 mg/kg and 30.0 mg/kg group, and the activities of GST decreased in ACN 30.0 mg/kg group, and of GSH-Px decreased in both doses group. However, the level of MDA [(0.68 +/- 0.16) nmol/mg pro] were significantly higher in 30.0 mg/kg group than that in control group [(0.38 +/- 0.12) nmol/mg pro] (P < 0.01). 2 weeks after stopping ACN treatment, the level of GSH restored to normal but the levels of MDA or the activity of GSH-Px in 30.0 mg/kg group were still higher or lower respectively than those of control (P < 0.05). CONCLUSION: ACN may impair the balance of antioxidant system, thus induce lipid peroxidation damage to rat testes.


Assuntos
Acrilonitrila/toxicidade , Peroxidação de Lipídeos/efeitos dos fármacos , Testículo/metabolismo , Animais , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Masculino , Malondialdeído/metabolismo , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Testículo/efeitos dos fármacos
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