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1.
AJNR Am J Neuroradiol ; 42(10): 1853-1858, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34615646

RESUMO

BACKGROUND AND PURPOSE: Vestibular schwannomas are common cerebellopontine angle tumors arising from the vestibulocochlear nerve and can result in cranial nerve dysfunction. Conventional MR imaging does not provide information that could correlate with cranial nerve compression symptoms of hearing loss or imbalance. We used multitensor tractography to evaluate the relationship between the WM microstructural properties of cranial nerves and tumor volume in a cohort of patients with vestibular schwannomas. MATERIALS AND METHODS: A retrospective study was performed in 258 patients with vestibular schwannomas treated at the Gamma Knife clinic at Toronto Western Hospital between 2014 and 2018. 3T MR images were analyzed in 160 surgically naïve patients with unilateral vestibular schwannomas. Multitensor tractography was used to extract DTI-derived metrics (fractional anisotropy and radial, axial, and mean diffusivities of the bilateral facial and vestibulocochlear nerves [cranial nerves VII/VIII]). ROIs were placed in the transition between cisternal and intracanalicular segments, and images were analyzed using the eXtended Streamline Tractography reconstruction method. Diffusion metrics were correlated with 3D tumor volume derived from the Gamma Knife clinic. RESULTS: DTI analyses revealed significantly higher fractional anisotropy values and a reduction in axial diffusivity, radial diffusivity, and mean diffusivity (all P < .001) within the affected cranial nerves VII and VIII compared with unaffected side. All specific diffusivities (axial, radial, and mean diffusivity) demonstrated an inverse correlation with tumor volume (axial, radial, and mean diffusivity, P < .01). CONCLUSIONS: Multitensor tractography allows the quantification of cranial nerve VII and VIII WM microstructural alterations in patients with vestibular schwannomas. Our findings support the hypothesis that tumor volume may cause microstructural alterations of the affected cranial nerves VII and VIII. This type of advanced imaging may represent a possible avenue to correlate diffusivities with cranial nerve function.


Assuntos
Neuroma Acústico , Nervos Cranianos , Nervo Facial , Humanos , Neuroma Acústico/diagnóstico por imagem , Estudos Retrospectivos , Carga Tumoral , Nervo Vestibulococlear/diagnóstico por imagem
2.
Int Endod J ; 54(8): 1317-1327, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33711171

RESUMO

AIM: To explore the proliferation, adhesion and differentiation response and the underlying mechanisms that occur in lipopolysaccharide (LPS)-induced inflamed dental pulp cells (DPCs) in contact with Biodentine and mineral trioxide aggregate (MTA). METHODOLOGY: The DPCs were isolated from three healthy donors and named DPC-H1 to DPC-H3. The DPCs were pre-cultured with 2 or 5 µg mL-1 LPS for 24 h to induce inflammation. The expression of inflammation marker miR-146a was detected by q-PCR. The normal and LPS-induced DPCs were further treated with 0.14 mg mL-1 Biodentine or 0.13 mg mL-1 MTA for 24 h. MTT assay and adhesion assay were used to analyse the changes of cell phenotypes. DSPP, AKT and ERK expressions were detected by Western blotting. The data were analysed by Mann-Whitney test or two-way anova. Differences were considered statistically significant when P < 0.05. RESULTS: In LPS-induced DPCs, Biodentine and MTA treatment neither induced nor aggravated LPS-induced inflammation, but their presence did increase the expression of the odontogenic differentiation marker DSPP. Under 2 or 5 µg mL-1 LPS-induced inflammation, Biodentine and MTA promoted the proliferation of DPC cells, and significantly in DPC-H2 (P < 0.0001 for both reagents). With the treatment of 2 µg mL-1 LPS, the cell adhesion of DPCs on the fibronectin-coated culture plates was increased significantly by Biodentine (P = 0.0413) and MTA (P < 0.0001). Biodentine and MTA regulated cell adhesion on the fibronectin-coated culture plates (P < 0.0001 for both reagents) and proliferation (P < 0.0001 for both reagents) via the AKT pathway. However, the AKT pathway was not involved in the expression of DSPP induced by Biodentine and MTA. CONCLUSION: Biodentine and MTA enhanced the proliferation, adhesion and differentiation of LPS-induced DPCs. The proliferation and adhesion process induced by Biodentine and MTA was via the AKT pathway. However, the cellular differentiation process might not use the same pathway, and this needs to be explored in future studies.


Assuntos
Polpa Dentária , Lipopolissacarídeos , Compostos de Alumínio/farmacologia , Compostos de Cálcio/farmacologia , Combinação de Medicamentos , Lipopolissacarídeos/farmacologia , Óxidos/farmacologia , Silicatos/farmacologia
3.
Toxicol In Vitro ; 33: 80-7, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26891812

RESUMO

The International Agency for Research on Cancer lists the principal component of betel quid (BQ), the areca nut, and that of cigarette smoke, benzo[a]pyrene (BaP), as Group 1 carcinogens. Epidemiological studies have shown that coexposure of BQ and cigarette smoke markedly increases the risk of cancer. We previously demonstrated that arecoline, the most abundant alkaloid in the areca nut, inhibits nucleotide excision repair through the repression of p53 activity. To investigate the combined potency of arecoline and BaP in carcinogenesis, we treated human epithelial HEp-2 cells with subcytotoxic doses of arecoline and BaP, alone or in combination, and examined the effects on DNA damage and repair. When exposed for 24h, BaP enhanced DNA repair and p53 transactivation activity. However, these enhancements were suppressed through concurrent treatment of the cells with arecoline. Using a Comet assay, we found that extended exposure to arecoline and BaP caused moderate-to-severe DNA damage in 60% of the cells. Expression of the XPD helicase was transcriptionally suppressed by 1 week of treatment with BaP. Our studies have revealed potential targets in the DNA repair pathway that are affected by BQ and tobacco components, as well as the effect of these components on carcinogenesis.


Assuntos
Arecolina/toxicidade , Benzo(a)pireno/toxicidade , Carcinógenos/toxicidade , Linhagem Celular Tumoral , Dano ao DNA , Reparo do DNA/efeitos dos fármacos , Sinergismo Farmacológico , Humanos
4.
J Hosp Infect ; 90(4): 344-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26028589

RESUMO

This was a two-phase prospective intervention study in the cardiology intensive care unit (CICU) and medical intensive care unit (MICU) and of a public 1800-bed medical centre in Taiwan. In phase I, cleaning efficacy was monitored by ATP bioluminescence after daily morning cleaning, and only 43.9% of 221 tested surfaces passed. The baseline data were used to define an intervention consisting of a new cleaning protocol as well as a new education/training programme. In phase II, following the intervention, 88.1% of 270 surfaces were found to be clean. The combined infection rate in the CICU and MICU showed a statistically significant decrease of 49.7%.


Assuntos
Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , Desinfecção/métodos , Contaminação de Equipamentos/prevenção & controle , Zeladoria Hospitalar/métodos , Centros Médicos Acadêmicos , Serviço Hospitalar de Cardiologia , Equipamentos Descartáveis , Equipamentos e Provisões Hospitalares/microbiologia , Pessoal de Saúde/educação , Humanos , Unidades de Terapia Intensiva , Medições Luminescentes , Estudos Prospectivos , Taiwan/epidemiologia
5.
Oncogene ; 31(2): 226-37, 2012 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-21666718

RESUMO

MicroRNAs (miRNAs) are endogenous non-coding RNAs that are known to be involved in the pathogenesis of tumors. Gastric carcinoma (GC) is a common malignancy worldwide. The aim of this study was the identification of the expression signature and functional roles of aberrant miRNAs in GC. Initial screening established a profile of aberrantly expressed miRNAs in tumors. miR-370 was confirmed to be overexpressed in GC tissues. Higher expression of miR-370 in GC tissues was associated with more advanced nodal metastasis and a higher clinical stage compared with controls. In addition, significantly higher level of miR-370 was noted in the plasma of GC patients compared with controls. Patients having more invasive or advanced tumors also exhibited a higher plasma level of miR-370. In vitro assays indicated that exogenous miR-370 expression enhanced the oncogenic potential of GC cells. The AGS-GFPM2 cells with exogenous miR-370 expression also exhibited enhanced abdominal metastatic dissemination in nude mice. Reporter assays confirmed that miR-370 targeted predicted sites in 3'UTR of transforming growth factor-ß receptor II (TGFß-RII) gene. The exogenous miR-370 expression decreased TGFß-RII expression and the phosphorylation of Smad3 elicited by TGFß1. The TGFß1-mediated repression in cell migration was reverted by exogenous miR-370 expression. A reverse correlation between miR-370 and TGFß-RII expression was noted in GC tissues. This study concludes that miR-370 is a miRNA that is associated with GC progression by downregulating TGFß-RII. The miRNA expression profile described in this study should contribute to future studies on the role of miRNAs in GC.


Assuntos
MicroRNAs/genética , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Neoplasias Gástricas/genética , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Receptor do Fator de Crescimento Transformador beta Tipo II , Neoplasias Gástricas/patologia
6.
Oral Dis ; 17(1): 53-9, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20646234

RESUMO

BACKGROUNDS: The chromosome 3q26 locus is a hotspot region carrying oncogenes that frequently altered in neoplasms. ZASC1 is a zinc finger protein transcription factor localized on 3q26. Our previous study showed the frequent amplification of 3q26, including the ZASC1 gene, in oral squamous cell carcinoma (OSCC). This study investigated the copy number changes of ZASC1 gene from primary to recurrent OSCC and the functions of ZASC1 in OSCC cells. MATERIALS AND METHODS: A total of 27 OSCC patients with primary and recurrent tumors were examined for ZASC1 and TERC copy number changes using Quantitative PCR analysis. Exogenous expression and knockdown of ZASC1 were carried out to specify the oncogenic potential of ZASC1 in OSCC cells. RESULTS: A ZASC1 copy number that has increased from primary to recurrent tumor counterparts in tissue pairs suggested the importance of ZASC1 in tumor progression. The increase of ZASC1 gene copy number in recurrent tumors was associated with the consumption of betel quid in patients. OSCC cells expressing ZASC1-FLAG fusion protein showed increased proliferation. After the knockdown of endogenous ZASC1 expression using small interference RNA, the growth and colony formation of SAS OSCC cells decreased. CONCLUSIONS: The findings support the hypothesis that ZASC1 localized on 3q26 contributes to the recurrence of OSCC.


Assuntos
Carcinoma de Células Escamosas/genética , Proteínas de Transporte/genética , Amplificação de Genes/genética , Dosagem de Genes/genética , Neoplasias Bucais/genética , Recidiva Local de Neoplasia/genética , Proteínas Nucleares/genética , Areca/efeitos adversos , Carcinoma de Células Escamosas/patologia , Proteínas de Ligação a DNA , Amplificação de Genes/efeitos dos fármacos , Dosagem de Genes/efeitos dos fármacos , Humanos , Análise por Pareamento , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , RNA/genética , Telomerase/genética
7.
J Dent Res ; 89(3): 252-7, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20110513

RESUMO

Differentiation of periodontal ligament (PDL) cells occurs under specific induction; furthermore, NF-kappaB signaling is important for regulation of bone differentiation. MicroRNAs are small non-coding RNAs that repress the translation of target genes and modulate cellular processes. miR-146a has been reported to modulate NF-kappaB signaling. This study hypothesized that miR-146a has a regulatory role in PDL differentiation by affecting NF-kappaB signaling. Immortalized PDL (I-PDL) cell lines were established by exogenous telomerase expression. The genesis of alkaline phosphatase and the up-regulation of miR-146a were induced by ascorbic acid in the I-PDL cells and primary PDL cells. I-PDL cells with exogenous miR-146a expression showed attenuation of NF-kappaB activity and exhibited higher differentiation relative to the controls. Exogenous NF-kappaB expression decreased the expression of differentiation markers, while the inactivation of endogenous NF-kappaB increased alkaline phosphatase in I-PDL cells. This study concludes that miR-146a promotes the differentiation in PDL cells through the down-regulation of NF-kappaB signaling.


Assuntos
Diferenciação Celular/fisiologia , Regulação para Baixo/fisiologia , MicroRNAs/fisiologia , NF-kappa B/metabolismo , Ligamento Periodontal/fisiologia , Fosfatase Alcalina/metabolismo , Humanos , Ligamento Periodontal/citologia , Transdução de Sinais/fisiologia
8.
J Hazard Mater ; 166(1): 200-6, 2009 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-19168283

RESUMO

A new modeling concept to evaluate the effects of cadmium and copper on heterotrophic growth rate constant (mu(H)) and lysis rate constant (b(H)) in activated sludge was introduced. The oxygen uptake rate (OUR) was employed to measure the constants. The results indicated that the mu(H) value decreased from 4.52 to 3.26 d(-1) or by 28% when 0.7 mg L(-1) of cadmium was added. Contrarily the b(H) value increased from 0.31 to 0.35 d(-1) or by 11%. When adding 0.7 mg L(-1) of copper, the mu(H) value decreased to 2.80 d(-1) or by 38%. The b(H) value increased to 0.42 d(-1) or by 35%. After regression, the inhibitory effect was in a good agreement with non-competitive inhibition kinetic. The inhibition coefficient values for cadmium and copper were 1.82 and 1.21 mg L(-1), respectively. The relation between the b(H) values and heavy metal concentrations agreed with exponential type well. The heavy metal would enhance b(H) value. Using these data, a new kinetic model was established and used to simulate the degree of inhibition. It was evident that not only the inhibitory effect on mu(H) but also that the enhancement effect on b(H) should be considered when heavy metal presented.


Assuntos
Bactérias/efeitos dos fármacos , Biodegradação Ambiental , Cádmio/farmacologia , Cobre/farmacologia , Modelos Teóricos , Esgotos/microbiologia , Bactérias/crescimento & desenvolvimento , Cinética
9.
J Dent Res ; 87(11): 1063-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18946016

RESUMO

MicroRNAs (miRNAs) are non-coding RNAs that play roles in gene silencing and may be involved in tumorigenesis. miR-211 was mapped to chromosome 15q13, a locus frequently altered in cancers. The role of miR-211 in carcinogenesis has not been clearly defined, however. This study investigated the pathogenetic implications of miR-211 in oral carcinogenesis. An association was found between higher miR-211 expression and the most advanced nodal metastasis, vascular invasion, and poor prognosis of oral carcinoma. The function of enforced miR-211 expression in oral carcinoma cells was confirmed by the repression of LacZ in a reporter plasmid via miR-211 targeting. Enforced miR-211 expression significantly increased the proliferation, migration, and anchorage-independent colony formation of oral carcinoma cells, while it enhanced the tumorigenicity of only SAS high-grade oral carcinoma cells, but not OECM-1 non-tumorigenic cells. The findings suggest that high miR-211 expression may be associated with the progression of oral carcinoma and poor patient outcomes.


Assuntos
Carcinoma de Células Escamosas/genética , MicroRNAs/biossíntese , Neoplasias Bucais/genética , Lesões Pré-Cancerosas/genética , Carcinoma de Células Escamosas/metabolismo , Estudos de Casos e Controles , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Neoplasias Bucais/metabolismo , Neovascularização Patológica , Fenótipo , Lesões Pré-Cancerosas/metabolismo , Prognóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
10.
J Periodontal Res ; 43(6): 673-80, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18624948

RESUMO

BACKGROUND AND OBJECTIVE: The objective was to define the roles of insulin-like growth factor binding protein-5 (IGFBP-5) in gingival epithelial cells (GEC). Human IGFBP-5 is expressed in many cell types and has diverse biological functions. It stimulates the growth of bone cells and is associated with the impedance of gingival fibroblast apoptosis. In gingival epithelium, IGFBP-5 is expressed in the cells of the differentiated stratum spinosum layer. MATERIAL AND METHODS: Recombinant IGFBP-5 protein treatment and knockdown of IGFBP-5 expression using a lentivirus-delivered short hairpin RNA was carried out in human GEC. Proliferation, apoptosis, anoikis, migration, differentiation and gene expression in GEC were analyzed and molecular images were obtained. RESULTS: The IGFBP-5 had no effect on proliferation, but it slightly suppressed apoptosis and anoikis of GEC. It also induced GEC migration and upregulated the expression of involucrin, transglutaminase-1, keratin and focal adhesion kinase. The IGFBP-5 induced migration partly via an insulin-like growth factor-independent mechanism. The knockdown of IGFBP-5 downregulated the expression of involucrin, transglutaminase-1 and focal adhesion kinase. CONCLUSION: Expression of IGFBP-5 in GEC is associated with anti-apoptosis, migration and differentiation of GEC. These phenotypic effects may be associated with focal adhesion kinase and are advantageous for re-epithelization of GEC and the maintenance of gingival health.


Assuntos
Gengiva/metabolismo , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/fisiologia , Apoptose , Diferenciação Celular/fisiologia , Linhagem Celular , Movimento Celular/fisiologia , Células Epiteliais/metabolismo , Proteína-Tirosina Quinases de Adesão Focal/biossíntese , Expressão Gênica , Técnicas de Silenciamento de Genes , Gengiva/citologia , Gengiva/efeitos dos fármacos , Humanos , Precursores de Proteínas/biossíntese , Proteínas Recombinantes/farmacologia , Transglutaminases/biossíntese
11.
J Pathol ; 214(3): 368-76, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18085517

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is a global malignancy. The insulin-like growth factor (IGF) signalling axis plays a critical role in tumourigenesis. This study defined the clinical and functional roles of insulin-like growth factor binding protein-5 (IGFBP-5) in HNSCC. Down-regulation of IGFBP-5 mRNA expression was found during the progression from pre-cancer to HNSCC. The down-regulation in HNSCC was associated with a higher propensity to nodal metastasis. SAS and OECM-1 are HNSCC cells that do, or do not, express IGFBP-5, respectively. Recombinant IGFBP-5 reduced the proliferation of OECM-1 cells and this was exerted mainly through blockade of the IGF pathways. Either IGFBP-5 or IGF-I treatment alone promoted OECM-1 migration, but a combination of treatments generated antagonistic effects. Overexpression of IGFBP-5 reduced the proliferation and anchorage-independent growth of both OECM-1 and SAS cells. Conversely, knockdown of IGFBP-5 expression significantly induced the proliferation and anchorage-independent growth of SAS cells. It also induced the growth of xenografted SAS tumours. SAS transfectants that expressed mutant or truncated IGFBP-5, which lack IGF binding activity, exhibited significantly lower anchorage-independent growth than vector control. This suggests that IGFBP-5 possesses an IGF-independent suppressor function. The suppressive effects of IGFBP-5 on the tumourigenesis of HNSCC might be invaluable to future neoplastic intervention.


Assuntos
Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/patologia , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/fisiologia , Animais , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/uso terapêutico , Fator de Crescimento Insulin-Like I/farmacologia , Fator de Crescimento Insulin-Like II/farmacologia , Camundongos , Camundongos SCID , Transplante de Neoplasias , Interferência de RNA , RNA Mensageiro/análise , RNA Interferente Pequeno/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução Genética
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