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1.
Br J Cancer ; 112(11): 1760-5, 2015 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-25965165

RESUMO

BACKGROUND: The overall survival for patients with squamous cell carcinoma of the tongue is low and the search for early diagnostic and prognostic markers is thus essential. MicroRNAs have been suggested as potential prognostic and diagnostic candidates in squamous cell carcinoma of head and neck in general. METHODS: On the basis of the known differences between sub-sites within the oral cavity, we investigated the expression and role of microRNA-424 in squamous cell carcinoma arising in tongue. MicroRNA levels were measured by qRT-PCR in both tissue and plasma samples. RESULTS: Levels of microRNA-424 were upregulated in tongue squamous cell carcinoma, but not in tumours originating from gingiva or floor of the mouth. Interestingly, microRNA-424 was downregulated in clinically normal tongue tissue next to tumour compared with completely healthy tongue, indicating that microRNA-424 could be a marker of field cancerisation in this tumour type. However, expression of microRNA-424 in a tongue-derived epithelial cell line revealed no significant changes in the expression profile of proteins and genes. CONCLUSIONS: Our patient data show that microRNA-424 alterations are a marker of field cancerisation specific for tongue tumourigenesis, which also could have a role in development of tongue squamous cell carcinoma.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma de Células Escamosas/sangue , MicroRNAs/sangue , Neoplasias da Língua/sangue , Idoso , Carcinogênese/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Língua , Neoplasias da Língua/genética , Neoplasias da Língua/patologia
2.
Osteoporos Int ; 24(7): 1973-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23340948

RESUMO

UNLABELLED: The study examined if women with osteoporosis were at increased risk of periodontal disease. Three hundred eighty females aged 45-65 years with recent dual-energy X-ray absorptiometry (DXA) scans of the spine and proximal femur agreed to a dental examination. No association was established between the presence of severe periodontal disease and osteoporosis. INTRODUCTION: The purpose of this study is to determine whether patients with osteoporosis have an increased severity and extent of periodontal disease, taking full account of confounding factors. METHODS: Volunteer dentate women (45-65 years), who had undergone recent DXA of the femur and lumbar spine, received a clinical examination of their periodontal tissues by a single trained operator who was blind to the subject's osteoporosis status. Clinical examinations were performed within 6 months of the DXA. Basic Periodontal Examination score, gingival bleeding score, periodontal pocket depth, recession and calculus were the periodontal outcome measures. Potential confounding factors were recorded. Logistic regression was performed for the dichotomous outcome measure of severe periodontal disease (present or absent) with osteoporotic status, adjusting for confounding factors. RESULTS: There were 380 dentate participants for whom DXA data were available. Of these, 98 had osteoporosis. When compared with osteoporotic subjects, those with normal bone mineral density were significantly younger (p = 0.01), had a higher body mass index (p = 0.03) and had more teeth (p = 0.01). The prevalence of severe periodontal disease in the sample was 39 %. The unadjusted odds ratio for the association between osteoporosis and severe periodontal disease was 1.21 (0.76 to 1.93). The adjusted odds ratio analysis including other covariates (age, smoking, hormone replacement therapy, alcohol) was 0.99 (0.61 to 1.61). CONCLUSION: No association was established between the presence of severe periodontal disease and osteoporosis.


Assuntos
Osteoporose Pós-Menopausa/complicações , Doenças Periodontais/complicações , Absorciometria de Fóton , Fatores Etários , Idoso , Índice de Massa Corporal , Densidade Óssea/fisiologia , Estudos Transversais , Inglaterra/epidemiologia , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/epidemiologia , Osteoporose Pós-Menopausa/fisiopatologia , Doenças Periodontais/epidemiologia , Prevalência
3.
Biointerphases ; 14(1): 011002, 2019 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-30700091

RESUMO

PolyJet three-dimensional (3D) printing allows for the rapid manufacturing of 3D moulds for the fabrication of cross-linked poly(dimethylsiloxane) microwell arrays (PMAs). As this 3D printing technique has a resolution on the micrometer scale, the moulds exhibit a distinct surface roughness. In this study, the authors demonstrate by optical profilometry that the topography of the 3D printed moulds can be transferred to the PMAs and that this roughness induced cell adhesive properties to the material. In particular, the topography facilitated immobilization of endothelial cells on the internal walls of the microwells. The authors also demonstrate that upon immobilization of endothelial cells to the microwells, a second population of cells, namely, pancreatic islets could be introduced, thus producing a 3D coculture platform.


Assuntos
Adesão Celular , Células Imobilizadas/fisiologia , Técnicas de Cocultura/métodos , Dimetilpolisiloxanos/metabolismo , Células Endoteliais/fisiologia , Células Secretoras de Glucagon/fisiologia , Células Secretoras de Insulina/fisiologia , Humanos , Ilhotas Pancreáticas , Impressão Tridimensional , Propriedades de Superfície
4.
Appl Spectrosc ; 59(5): 611-9, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15969806

RESUMO

Spectroscopic techniques such as Raman, mid-infrared (MIR), and near-infrared (NIR) have become indispensable analytical tools for rapid chemical quality control and process monitoring. This paper presents the application of in-line Fourier transform near-infrared (FT-NIR) spectroscopy, Raman spectroscopy, and ultrasound transit time measurements for in-line monitoring of the composition of a series of high-density polyethylene (HDPE)/polypropylene (PP) blends during single-screw extrusion. Melt composition was determined by employing univariate analysis of the ultrasound transit time data and partial least squares (PLS) multivariate analysis of the data from both spectroscopic techniques. Each analytical technique was determined to be highly sensitive to changes in melt composition, allowing accurate prediction of blend content to within +/- 1% w/w (1sigma) during monitoring under fixed extrusion conditions. FT-NIR was determined to be the most sensitive of the three techniques to changes in melt composition. A four-factor PLS model of the NIR blend spectra allowed determination of melt content with a standard prediction error of +/- 0.30% w/w (1sigma). However, the NIR transmission probes employed for analysis were invasive into the melt stream, whereas the single probes adopted for Raman and ultrasound analysis were noninvasive, making these two techniques more versatile. All three measurement techniques were robust to the high temperatures and pressures experienced during melt extrusion, demonstrating each system's suitability for process monitoring and control.


Assuntos
Algoritmos , Manufaturas/análise , Teste de Materiais/métodos , Polietileno/química , Polipropilenos/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos , Ultrassonografia/métodos , Técnicas de Química Combinatória/métodos , Sistemas On-Line , Polietileno/análise , Polipropilenos/análise , Integração de Sistemas , Temperatura de Transição , Vibração
5.
Biomaterials ; 23(21): 4295-302, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12194532

RESUMO

The commercial success of hydroxyapatite (HA) filled polyethylene composite has generated growing interest in improving the processability of the composite. A number of synthetic procedures and post synthesis heat treatment of HA has lead to the availability of powders with widely varying morphological features. This paper addresses the effect of morphological features of HA on the rheology and processability of an injection-moulding grade HA-HDPE composite. The results showed that low surface area HA filled composite exhibited better injection processing characteristics through improved rheological responses. The effect of reducing the surface area of the filler is to require less polyethylene to wet the filler and allows more polyethylene to be involved in the flow processes. These changes reduced the temperatures and pressures required for successful processing.


Assuntos
Materiais Biocompatíveis/química , Durapatita/química , Polietilenos/química , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Reologia , Propriedades de Superfície , Temperatura
6.
Br J Pharmacol ; 166(1): 194-209, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21745189

RESUMO

BACKGROUND AND PURPOSE: Renal ischaemia-reperfusion (IR) injury is an inevitable consequence of renal transplantation, causing significant graft injury, increasing the risk of rejection and contributing to poor long-term graft outcome. Renal injury is mediated by cytokine and chemokine synthesis, inflammation and oxidative stress resulting from activation of the NF-κB pathway. EXPERIMENTAL APPROACH: We utilized liposomal incorporation of a potent inhibitor of the NF-κB pathway, curcumin, to target delivery to renal tubular epithelial and antigen-presenting cells. Liposomes containing curcumin were administered before bilateral renal ischaemia in C57/B6 mice, with subsequent reperfusion. Renal function was assessed from plasma levels of urea and creatinine, 4 and 24 h after reperfusion. Renal tissue was examined for NF-κB activity and oxidative stress (histology, immunostaining) and for apoptosis (TUNEL). Cytokines and chemokines were measured by RT-PCR and Western blotting. KEY RESULTS: Liposomal curcumin significantly improved serum creatinine, reduced histological injury and cellular apoptosis and lowered Toll-like receptor-4, heat shock protein-70 and TNF-α mRNA expression. Liposomal curcumin also reduced neutrophil infiltration and diminished inflammatory chemokine expression. Curcumin liposomes reduced intracellular superoxide generation and increased superoxide dismutase levels, decreased inducible NOS mRNA expression and 3-nitrotyrosine staining consistent with limitations in nitrosative stress and inhibited renal tubular mRNA and protein expression of thioredoxin-interacting protein. These actions of curcumin were mediated by inhibition of NF-κB, MAPK and phospho-S6 ribosomal protein. CONCLUSIONS AND IMPLICATIONS: Liposomal delivery of curcumin promoted effective, targeted delivery of this non-toxic compound that provided cytoprotection via anti-inflammatory and multiple antioxidant mechanisms following renal IR injury.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Curcumina/farmacologia , Sistemas de Liberação de Medicamentos , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Células Apresentadoras de Antígenos , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Western Blotting , Quimiocinas/metabolismo , Curcumina/administração & dosagem , Citocinas/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Marcação In Situ das Extremidades Cortadas , Túbulos Renais/citologia , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/patologia , Lipossomos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Traumatismo por Reperfusão/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo
7.
Int J Cancer ; 87(3): 368-72, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10897041

RESUMO

The p53 homologue p63 is essential for ectodermal differentiation, such that p63-/- mice lack all squamous epithelia and teeth. The p63 gene expresses at least 6 different transcripts, but information regarding the expression, regulation and function of the different isoforms has remained sparse, due to the lack of adequate reagents directed specifically against the individual proteins. Here we characterize the expression of p63 alpha/delta Np63 alpha in benign and malignant lesions of the oral epithelium, using a specific antibody raised against a peptide derived from the C-terminus of p63 alpha, which does not cross-react with p53 or the other p53 homologue, p73. By immunohistochemical analysis, we show that these p63 isoforms are expressed in the nucleus of many cells. In normal and benign lesions, p63 alpha/delta Np63 alpha-expressing cells are mainly found suprabasally, whereas p53-expressing cells are restricted to the basal-cell layer. By RT-PCR, we show that delta Np63 alpha is the predominant isoform in cell lines from squamous-cell carcinomas of the head and neck, confirming our immunochemical observations. Our data are consistent with studies suggesting a role for p63 in the transit-amplifying population of epidermal cells. Over-expression of p63 alpha, and in particular the delta N form, was frequently seen in carcinomas. Taken together with previous analyses of p63 expression, our data suggest distinct roles for different p63 isoforms in the regulation of growth and/or differentiation of epithelial cells. Moreover, our data are compatible with the notion that p63 can act to promote neoplastic growth in the oral epithelium.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Regulação da Expressão Gênica , Proteínas de Membrana , Doenças da Boca/metabolismo , Mucosa Bucal/metabolismo , Neoplasias Bucais/metabolismo , Proteínas de Neoplasias/biossíntese , Fosfoproteínas/biossíntese , Isoformas de Proteínas/biossíntese , Transativadores , Sequência de Aminoácidos , Animais , Anticorpos/imunologia , Especificidade de Anticorpos , Antígenos de Neoplasias/biossíntese , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Proteínas de Ligação a DNA , Epitopos/imunologia , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Humanos , Hiperplasia , Líquen Plano Bucal/genética , Líquen Plano Bucal/metabolismo , Líquen Plano Bucal/patologia , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Doenças da Boca/genética , Doenças da Boca/patologia , Mucosa Bucal/patologia , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/imunologia , Fosfoproteínas/genética , Fosfoproteínas/imunologia , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , Coelhos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição , Proteínas Supressoras de Tumor
8.
J Pediatr ; 123(2): 177-84, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8345411

RESUMO

Familial combined hyperlipidemia (FCHL) is a dominantly inherited hyperlipidemia that occurs in at least 1% of the adult population and is responsible for 10% of premature coronary artery disease. In families referred for evaluation because of primary hyperlipidemia in a child, FCHL is expressed three times more commonly than familial hypercholesterolemia and half of the siblings are affected. Several metabolic defects apparently are associated with the FCHL phenotype. Most commonly, excess production of very low density lipoprotein apolipoprotein B can be demonstrated. In other families, reduced lipoprotein lipase activity is associated. One allele at a locus influencing apolipoprotein B levels predicts FCHL in a large proportion of families ascertained through affected children. Whether this allele is responsible for the excess of very low density lipoprotein apolipoprotein B detected in metabolic studies has not been elucidated. Management of FCHL in children begins with dietary modification. A bile acid sequestrant may be considered as well if diet cannot reduce the plasma low-density lipoprotein cholesterol level to less than 4.13 mmol/L (160 mg/dl) after the age of 10 years. Although the hydroxymethylglutaryl-coenzyme A reductase inhibitors are not currently recommended for children younger than 19 years of age, we speculate that they will be increasingly utilized for the management of FCHL in teenage boys who continue to have low density lipoprotein cholesterol levels greater than 4.13 mmol/L (160 mg/dl) after dietary modification.


Assuntos
Hiperlipidemia Familiar Combinada , Adolescente , Apolipoproteínas B/sangue , Criança , Pré-Escolar , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Resina de Colestiramina/uso terapêutico , Colestipol/uso terapêutico , Terapia Combinada , Doença das Coronárias/etiologia , Ingestão de Energia , Feminino , Ligação Genética , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases , Hiperlipidemia Familiar Combinada/complicações , Hiperlipidemia Familiar Combinada/genética , Hiperlipidemia Familiar Combinada/metabolismo , Hiperlipidemia Familiar Combinada/terapia , Lipoproteínas VLDL/sangue , Fígado/metabolismo , Masculino , Família Multigênica/genética , Niacina/uso terapêutico , Fenótipo , Polimorfismo Genético , Triglicerídeos/sangue
9.
J Pediatr ; 122(3): 477-82, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8441109

RESUMO

We studied the effectiveness of and compliance with the use of cholestyramine in children with heterozygous familial hypercholesterolemia (FH) and familial combined hyperlipidemia (FCHL). During a 10-year period, 673 children (aged 10.5 +/- 4.0 years) were referred for evaluation of hyperlipidemia, of whom 87 (36 with FH; 51 with FCHL) were treated with cholestyramine (8 to 24 gm/day). In both groups, total cholesterol, low-density lipoprotein (LDL)-cholesterol, and apolipoprotein B levels were significantly reduced after cholestyramine use. In those with FH, plasma LDL-cholesterol levels decreased from 258 +/- 35 mg/dl (6.67 +/- 0.90 mmol/L) to 190 +/- 31 mg/dl (4.91 +/- 0.80 mmol/L); in those with FCHL, LDL-cholesterol levels dropped from 207 +/- 40 mg/dl (5.35 +/- 1.03 mmol/L) to 141 +/- 35 mg/dl (3.64 +/- 0.90 mmol/L). High-density lipoprotein-cholesterol levels were not significantly changed after cholestyramine use in either group. In the FCHL group, plasma triglyceride levels increased significantly from 81 +/- 35 mg/dl (0.92 +/- 0.40 mmol/L) to 134 +/- 42 mg/dl (1.52 +/- 0.48 mmol/L). Seven patients were lost to follow-up; 18 discontinued the medication within 1 month. Of the remaining 62 children, 59 had a good response to the drug. Of the 62 patients, 52 discontinued the medication after 21.9 +/- 10 months. Adverse effects included foul taste (73%), nausea with bloating (18%), and constipation. Cholestyramine is effective in reducing LDL-cholesterol levels in children with inherited hyperlipidemia, but the majority of children will not comply with its long-term use.


Assuntos
Resina de Colestiramina/uso terapêutico , Hiperlipidemia Familiar Combinada/tratamento farmacológico , Adolescente , Apolipoproteínas B/sangue , Criança , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Resina de Colestiramina/efeitos adversos , Seguimentos , Humanos , Hiperlipidemia Familiar Combinada/sangue , Cooperação do Paciente , Triglicerídeos/sangue
10.
Curr Probl Pediatr ; 24(9): 295-305, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7859485

RESUMO

The first evidence that elevation of plasma levels of cholesterol is a risk factor for the development of atherosclerosis in children came from the Bogalusa Heart Study in 1986, which reported an association between aortic fatty streaks in 3- to 26-year-old subjects and increased plasma levels of low-density lipoprotein cholesterol (LDL-C). The most compelling evidence of a cause-and-effect relationship has come from the multicenter cooperative study called the Pathobiological Determinants of Atherosclerosis in Youth. When the investigators examined the abdominal aorta and the right coronary artery of adolescents and young adults who had died of trauma, they found a significant relationship between the sum of the very low density lipoprotein (VLDL) plus LDL-C level and both fatty streaks and raised atherosclerotic lesions. They also found an inverse relationship between those lesions and increased high-density lipoprotein cholesterol (HDL-C) levels. In addition, their studies showed that smoking (as assessed by the serum thiocyanate level) promotes atherogenesis in children as young as age 15 years. Thus many pediatricians have now accepted the importance of identifying children with significant hypercholesterolemia so that appropriate dietary and life-style modifications can be recommended. This is especially important because there is often a major genetic component to the hyperlipidemia seen in children.


Assuntos
Hiperlipidemia Familiar Combinada , Adolescente , Adulto , Transporte Biológico , Criança , Pré-Escolar , Resina de Colestiramina/uso terapêutico , Dieta com Restrição de Gorduras , Humanos , Hiperlipidemia Familiar Combinada/genética , Hiperlipidemia Familiar Combinada/metabolismo , Lipoproteínas/metabolismo , Lovastatina/uso terapêutico , Niacina/uso terapêutico
11.
J Pharmacokinet Biopharm ; 8(3): 229-42, 1980 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7420268

RESUMO

The bioavailability of theophylline from alcoholic and aqueous oral solutions was compared to that from an intravenous dose in 12 normal adults. The alcoholic elixir surprisingly gave rise to a significantly greater (114 +/- 14%, mean +/- SD) amount absorbed than did the intravenous dose. The aqueous solution (99 +/- 8%) and intravenous dose were statisticlly indistinguishable in this respect, and, furthermore, the extent of absorption from a 300-mg dose of the aqueous solution was 99 +/- 10% of that from a 500-mg dose, and not statistically different. The aqueous solution was thus employed in three subsequent studies as a standard with which to compare 13 different types of theophylline tablets, all marketed in the United States. Of the 13 tablets, eight showed bioavailability statistically distinguishable from that of the standard. Nevertheless, for only two tablets could it be claimed with 95% confidence level that the bioavailability was less than 95%. For none can it be stated at this confidence level that the bioavailability is less than 90%. Bioavailability studies should include criteria of clinical significance in addition to criteria of statistical significance. Contrary to the usual rationale behind choice of a bioavailability standard, nine of the 12 uncoated tablets appeared to allow more rapid absorption of theophylline than did the standard oral solution, an aqueous syrup. Increasing the dose of syrup decreased the rate of theophylline absorption. Orally administered drug solutions may have properties more absorption rate limiting than the disintegration of many brands of tablet.


Assuntos
Teofilina/metabolismo , Absorção , Adulto , Disponibilidade Biológica , Biotransformação , Feminino , Humanos , Masculino , Saliva/metabolismo , Fatores de Tempo
12.
J Pharmacokinet Biopharm ; 8(2): 131-49, 1980 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7431219

RESUMO

Absorption of theophylline from three commerical products labeled as sustained release was compared to the absorption from a standard uncoated tablet (Searle 200-mg aminophylline tablet) in a single-dose study. Aminodur tablets (Cooper) and Slophyllin Gyrocap capsules (Dooner) had bioavailability (100.2% +/- 19.8% and 98.5% +/- 13.8%) statistically indistinguishable from that of the standard but showed significantly slower absorption (peak times of 10.4 +/- 2.8 and 4.36 +/- 1.35 hr) and lower peak plasma concentrations (13.9 +/- 4.5 and 22.6 +/- 3.5 micrograms/ml/g dose) than the standard (tpeak, 1.52 +/- 0.45 hr; Cpeak, 28.1 +/- 6.2 micrograms/ml/g dose). The time of the plasma concentration peak (2.47 +/- 1.38 hr) after a dose of Tedral S.A. (Warner/Chilcott) was not statistically different from that after the standard, but both the peak concentration (16.0 +/- 3.9 micrograms/ml/g dose) and availability (76.0 +/- 18.4%) were. Multiple-dose projections from single-dose data indicate that of the three test products only Aminodur maintains reasonably constant interdose plasma levels during 12 hoursly dosing. With an 8 hourly dosing schedule Gyrocaps also might be satisfactory. Reasonable predictions of the plasma concentrations arising from Aminodur doses have been made using a single-compartment body model and assuming input from an outer followed by an inner layer of the tablet.


Assuntos
Absorção Intestinal , Teofilina/metabolismo , Disponibilidade Biológica , Preparações de Ação Retardada , Estudos de Avaliação como Assunto , Humanos , Cinética , Saliva/análise , Teofilina/administração & dosagem
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