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1.
J Periodontal Res ; 51(3): 342-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26271967

RESUMO

BACKGROUND AND OBJECTIVE: Ultraviolet (UV)-irradiated 7-dehydrocholesterol (7-DHC) and vitamin E (VitE)-coated titanium (Ti) implants have a beneficial effect on bone cells. Human gingival fibroblasts (HGFs) are the most abundant cells in periodontal tissues and are involved in the wound healing and repair. The objective of this study was to evaluate the response of HGFs to Ti implants coated with UV-irradiated 7-DHC and VitE, for improved soft-tissue integration of dental implants. MATERIAL AND METHODS: Ti surfaces were coated with 7-DHC and VitE, irradiated with UV light and incubated for 48 h at 23°C to allow cholecalciferol (D3 ) synthesis from 7-DHC onto the Ti surface. HGFs were cultured on the modified surfaces and the influence of the coating on these cells was evaluated through the analysis of: (i) biocompatibility; (ii) the mRNA levels of genes involved in the composition and turnover of the extracellular matrix, the inflammatory response, periodontal bone resorption and wound healing; and (iii) the levels of MMP-1 and TIMP-1 proteins. RESULTS: We found a beneficial effect of UV-irradiated 7-DHC:VitE-coated Ti implants on HGFs. Besides being biocompatible with HGFs, the UV-irradiated 7-DHC and VitE coating increased the levels of collagen III α1 and fibronectin mRNAs. and decreased the level of interleukin-8 mRNA. TIMP-1 was increased at both mRNA and protein levels in HGFs cultured on UV-irradiated 7-DHC:VitE-coated Ti implants. Finally, the UV-irradiated 7-DHC and VitE coating decreased the level of RANKL mRNA in HGFs. CONCLUSION: UV-irradiated 7-DHC:VitE-coated Ti implants have a positive effect on HGFs in vitro by reducing the inflammatory response and extracellular matrix breakdown.


Assuntos
Materiais Revestidos Biocompatíveis/farmacologia , Implantes Dentários , Fibroblastos/efeitos dos fármacos , Gengiva/efeitos dos fármacos , Titânio/química , Raios Ultravioleta , Vitamina D/farmacologia , Vitamina E/farmacologia , Adulto , Perda do Osso Alveolar/terapia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Colágeno Tipo III/análise , Desidrocolesteróis/farmacologia , Desidrocolesteróis/efeitos da radiação , Feminino , Fibroblastos/química , Fibronectinas/análise , Expressão Gênica , Humanos , Interleucina-8/análise , Masculino , Metaloproteinase 1 da Matriz/análise , Pessoa de Meia-Idade , Ligante RANK/análise , RNA Mensageiro/análise , Propriedades de Superfície , Inibidor Tecidual de Metaloproteinase-1/análise , Vitamina D/efeitos da radiação , Vitamina E/efeitos da radiação , Cicatrização
2.
J Periodontal Res ; 49(4): 425-36, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23919718

RESUMO

BACKGROUND AND OBJECTIVE: Gingival fibroblasts are responsible for the constant adaptation, wound healing and regeneration of gingival connective tissue. New titanium-zirconium (TiZr) abutment surfaces have been designed to improve soft tissue integration and reduce implant failure compared with titanium (Ti). The aim of the present study was first to characterize a primary human gingival fibroblast (HGF) model and secondly to evaluate their differential response to Ti and TiZr polished (P), machined (M) and machined + acid-etched (modMA) surfaces, respectively. MATERIAL AND METHODS: HGF were cultured on tissue culture plastic or on the different Ti and TiZr surfaces. Cell morphology was evaluated through confocal and scanning electron microscopy. A wound healing assay was performed to evaluate the capacity of HGF to close a scratch. The expression of genes was evaluated by real-time RT-PCR, addressing: (i) extracellular matrix organization and turnover; (ii) inflammation; (iii) cell adhesion and structure; and (iv) wound healing. Finally, cells on Ti/TiZr surfaces were immunostained with anti-ITGB3 antibodies to analyze integrin ß3 production. Matrix metalloproteinase-1 (MMP1) and inhibitor of metallopeptidases-1 (TIMP1) production were analyzed by enzyme-linked immunosorbent assays. RESULTS: On tissue culture plastic, HGF showed no differences between donors on cell proliferation and on the ability for wound closure; α-smooth muscle actin was overexpressed on scratched monolayers. The differentiation profile showed increased production of extracellular matrix components. Ti and TiZr showed similar biocompatibility with HGF. TiZr increased integrin-ß3 mRNA and protein levels, compared with Ti. Cells on TiZr surfaces showed higher MMP1 protein than Ti surfaces, although similar TIMP1 protein production. In this in vitro experiment, P and M surfaces from both Ti and TiZr showed better HGF growth than modMA. CONCLUSION: Taking into account the better mechanical properties and bioactivity of TiZr compared with Ti, the results of the present study show that TiZr is a potential clinical candidate for soft tissue integration and implant success.


Assuntos
Materiais Dentários/química , Fibroblastos/fisiologia , Gengiva/fisiologia , Titânio/química , Zircônio/química , Condicionamento Ácido do Dente/métodos , Actinas/análise , Materiais Biocompatíveis/química , Adesão Celular/fisiologia , Técnicas de Cultura de Células , Proliferação de Células , Forma Celular/fisiologia , Células Cultivadas , Corrosão Dentária/métodos , Polimento Dentário/métodos , Proteínas da Matriz Extracelular/análise , Gengiva/citologia , Humanos , Integrina beta3/análise , Teste de Materiais , Metaloproteinase 1 da Matriz/análise , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Inibidor Tecidual de Metaloproteinase-1/análise
3.
J Dent ; 42(1): 30-8, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24252800

RESUMO

OBJECTIVES: The aim of this study was to evaluate the influence of different titanium zirconium (TiZr) alloy surfaces on primary human gingival fibroblasts (HGF) for improved soft tissue integration of dental implants. METHODS: TiZr polished, machined and machined+HCl/H2SO4 acid-etched surfaces were modified by cathodic polarization and/or HNO3/HF acid etching. Contact angle of surfaces was measured. The influence of modified TiZr surfaces on HGF was evaluated through the analysis of cell number, morphology, recovery after a wound (wound healing assay) and the expression of several genes, including matrix metalloproteinase-1 (MMP1) and metallopeptidase inhibitor-1 (TIMP1). RESULTS: Modification of TiZr surfaces decreased its hydrophilicity. Hydride implementation on TiZr surfaces via cathodic polarization increased TIMP1 expression and decreased MMP1/TIMP1 mRNA ratio. Cathodic polarization of machined surfaces promoted cell attachment. Cells on machined and machined+cathodic polarization surfaces grew aligned to the microgrooves whereas on all polished surfaces they grew randomly. Acid etching of polished and machined surfaces did not improve HGF function. CONCLUSIONS: Hydride implementation on TiZr machined surfaces may be used as new dental implant material for improved soft tissue integration. CLINICAL SIGNIFICANCE: Enhancing dental implant surfaces' bioactivity by hydride implementation may promote soft tissue attachment and sealing around the implant and reduce peri-implantitis related to ECM-destruction compared with conventional machined surfaces.


Assuntos
Ligas/química , Ligas Dentárias/química , Implantes Dentários , Planejamento de Prótese Dentária , Gengiva/citologia , Condicionamento Ácido do Dente/métodos , Adulto , Contagem de Células , Técnicas de Cultura de Células , Proliferação de Células , Forma Celular , Células Cultivadas , Polimento Dentário/métodos , Feminino , Fibroblastos/fisiologia , Humanos , Ácido Clorídrico/química , Ácido Fluorídrico/química , Teste de Materiais , Metaloproteinase 1 da Matriz/análise , Inibidores de Metaloproteinases de Matriz/análise , Ácido Nítrico/química , Polarografia , Ácidos Sulfúricos/química , Propriedades de Superfície , Inibidor Tecidual de Metaloproteinase-1/análise , Molhabilidade
4.
J Biomed Mater Res A ; 101(6): 1768-77, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23197406

RESUMO

The aim of this study was to investigate the effect of TiO2 scaffold (SC) coated with an alginate hydrogel containing a proline-rich peptide (P2) on osteoblast proliferation and differentiation in vitro. Peptide release was evaluated and a burst release was observed during the first hours of incubation, and then progressively released overtime. No changes were observed in the cytotoxicity after 48 h of seeding MC3T3-E1 cells on the coated and uncoated TiO2 SC. The amount of cells after 7 days was higher on uncoated TiO2 SC than on alginate-coated TiO2 SC, measured by DNA content and scanning electron microscope imaging. In addition, while lower expression of integrin beta1 was detected for alginate-coated TiO2 SC at this time point, similar gene expression was observed for other integrins, fibronectin-1, and several osteoblast differentiation markers. After 21 days, gene expression of integrin beta3, fibronectin-1, osterix, and collagen-I was increased in alginate-coated compared to TiO2 SC. Moreover, increased gene expression of integrin alpha8, bone morphogenetic protein 2, interleukin-6, and collagen-I was found on P2 alginate-coated TiO2 SC compared to alginate-coated TiO2 SC. In conclusion, our results indicate that alginate-coated TiO2 SC can act as a matrix for delivery of proline-rich peptides increasing osteoblast differentiation. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.


Assuntos
Alginatos/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Osteoblastos/citologia , Peptídeos/farmacologia , Tecidos Suporte/química , Titânio/farmacologia , Sequência de Aminoácidos , Animais , Biomarcadores/metabolismo , Adesão Celular/efeitos dos fármacos , Adesão Celular/genética , Contagem de Células , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Meios de Cultura , Regulação da Expressão Gênica/efeitos dos fármacos , Ácido Glucurônico/farmacologia , Ácidos Hexurônicos/farmacologia , L-Lactato Desidrogenase/metabolismo , Camundongos , Dados de Sequência Molecular , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Peptídeos/química , Domínios Proteicos Ricos em Prolina , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
5.
Acta Biomater ; 9(3): 5759-70, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23201015

RESUMO

Vitamin D plays a central role in bone regeneration, and its insufficiency has been reported to have profound negative effects on implant osseointegration. The present study aimed to test the in vitro biological effect of titanium (Ti) implants coated with UV-activated 7-dehydrocholesterol (7-DHC), the precursor of vitamin D, on cytotoxicity and osteoblast differentiation. Fourier transform infrared spectroscopy confirmed the changes in chemical structure of 7-DHC after UV exposure. High-pressure liquid chromatography analysis determined a 16.5±0.9% conversion of 7-DHC to previtamin D(3) after 15min of UV exposure, and a 34.2±4.8% of the preD(3) produced was finally converted to 25-hydroxyvitamin D(3) (25-D(3)) by the osteoblastic cells. No cytotoxic effect was found for Ti implants treated with 7-DHC and UV-irradiated. Moreover, Ti implants treated with 7-DHC and UV-irradiated for 15min showed increased 25-D(3) production, together with increased ALP activity and calcium content. Interestingly, Rankl gene expression was significantly reduced in osteoblasts cultured on 7-DHC-coated Ti surfaces when UV-irradiated for 15 and 30min to 33.56±15.28% and 28.21±4.40%, respectively, compared with the control. In conclusion, these findings demonstrate that UV-activated 7-DHC is a biocompatible coating of Ti implants, which allows the osteoblastic cells to produce themselves active vitamin D, with demonstrated positive effects on osteoblast differentiation in vitro.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Desidrocolesteróis/efeitos da radiação , Osteoblastos/citologia , Próteses e Implantes , Ligante RANK/genética , Titânio/farmacologia , Raios Ultravioleta , Fosfatase Alcalina/metabolismo , Animais , Calcificação Fisiológica/efeitos dos fármacos , Calcificação Fisiológica/genética , Contagem de Células , Diferenciação Celular/genética , Linhagem Celular , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Colecalciferol/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos da radiação , Camundongos , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/enzimologia , Osteoblastos/efeitos da radiação , Ligante RANK/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo
6.
An. pediatr. (2003, Ed. impr.) ; 77(5): 323-328, nov. 2012. tab
Artigo em Espanhol | IBECS | ID: ibc-106664

RESUMO

Introducción: La detección de la exposición prenatal a drogas de abuso es fundamental para asegurar un adecuado seguimiento de los niños afectados. El cuestionario materno no es una herramienta de cribado eficiente. En los últimos años, se ha descrito la utilidad del cabello materno y del meconio como matrices biológicas para valorar esta exposición. El objetivo de este estudio es comparar ambas matrices alternativas en la detección de la exposición prenatal a drogas en el tercer trimestre del embarazo, con la finalidad de valorar su uso como herramienta de cribado. Pacientes y métodos: Entre enero y marzo de 2010 se recogieron muestras de cabello materno y meconio de 107 parejas madre-recién nacido del Hospital Can Misses de Ibiza. Se determinó en ambas matrices la presencia de opiáceos, cocaína, cannabis y anfetaminas, utilizando técnicas cromatográficas estandarizadas. Resultados: El análisis del cabello materno fue positivo para drogas de abuso en 17 casos (15,9%): 11 a cannabis, 7 a cocaína, uno a cannabis y éxtasis, y uno a cannabis y cocaína. Solo una madre había declarado consumo de cannabis y otra de cocaína. De los 7 casos positivos para cocaína en cabello, 6 se confirmaron en el estudio de meconio, mientras que de los 11 casos positivos para cannabis, solo 3 fueron confirmados en meconio. Se definieron 2 perfiles diferenciados de consumidoras: cocaína y cannabis (solo se detectaron 2 casos de policonsumo). Se detectó un caso con los valores de cocaína en meconio más altos publicados (1.582ng/g). Discusión: Este estudio revela una elevada prevalencia del consumo de drogas de abuso durante el embarazo en esta cohorte. La mejora en los métodos de cribado podría optimizar la prevención y el seguimiento de los recién nacidos expuestos. El cabello materno parece ser más sensible que el meconio para detectar la exposición prenatal a cannabis durante el tercer trimestre, por lo que podría convertirse en una buena herramienta de cribado(AU)


Introduction: Detection of prenatal drug abuse exposure is essential to ensure an appropriate monitoring of affected children. A maternal questionnaire is not an efficient screening tool. The usefulness of maternal hair and meconium as biological materials to assess this exposure has been described in last few years. The aim of this study was to compare both these alternative biological materials for prenatal drug exposure detection in the third trimester of pregnancy, in order to assess its use as a screening tool. Patients and methods: Between January and March 2010, samples of maternal hair and meconium from 107 mother-infant dyads were collected in Can Misses Hospital, Ibiza. The presence of opiates, cocaine, cannabis, and amphetamines, was determined in both materials, using standard chromatographic techniques. Results: Maternal hair analysis showed a 15.9% positivity for drugs of abuse (17 cases): 11 cannabis, 7 cocaine, 1 cannabis and ecstasy, and 1 cannabis and cocaine. Only one mother reported cannabis consumption and another one, cocaine. Of the 7 cocaine positive cases in hair, 6 were confirmed in meconium analysis, while of 11 cannabis positive cases, only 3 were confirmed in meconium. Two different consumer profiles were defined: cocaine consumers and cannabis consumers (with only 2 cases of multiple drug use). The highest level of cocaine ever published was detected (1.582ng/g) in one case. Discussion: This study reveals a high prevalence of drug abuse in this cohort during pregnancy. Improved screening methods may optimize prevention and monitoring of exposed infants. Maternal hair seems to be more sensitive than meconium to detect prenatal exposure to cannabis during the third trimester, so it might become a good screening tool(AU)


Assuntos
Humanos , Masculino , Feminino , Gravidez , Recém-Nascido , Transtornos Relacionados ao Uso de Substâncias/complicações , Complicações na Gravidez/diagnóstico , Cuidado Pré-Natal , Diagnóstico Pré-Natal/métodos , /induzido quimicamente , /fisiopatologia , Cromatografia/instrumentação , Cromatografia , Relações Materno-Fetais/fisiologia , Relações Mãe-Filho , Troca Materno-Fetal , Cabelo , Mecônio , Inquéritos e Questionários
7.
Biomed Mater ; 7(5): 055003, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22782012

RESUMO

Polyproline-rich synthetic peptides have previously been shown to induce bone formation and mineralization in vitro and to decrease bone resorption in vivo. Alginate hydrogel formulations containing these synthetic peptides (P2, P5, P6) or Emdogain® (EMD) were tested for surface coating of bone implants. In an aqueous environment, the alginate hydrogels disclosed a highly compact structure suitable for cell adhesion and proliferation. Lack of cytotoxicity of the alginate-gel coating containing peptides was tested in MC3T3-E1 cell cultures. In the present study, relative mRNA expression levels of integrin alpha 8 were induced by P5 compared to untreated alginate gel, and osteopontin mRNA levels were increased after 21 days of culture by treatment with synthetic peptides or EMD compared to control. Further, in agreement with previous results when the synthetic peptides were administered in the culture media, osteocalcin mRNA was significantly upregulated after long-term treatment with the formulated synthetic peptides compared to untreated and EMD alginate gel. These results indicate that the alginate gel is a suitable carrier for the delivery of synthetic peptides, and that the formulation is promising as biodegradable and biocompatible coating for bone implants.


Assuntos
Alginatos , Substitutos Ósseos/química , Osteoblastos/citologia , Peptídeos/química , Células 3T3 , Sequência de Aminoácidos , Animais , Sequência de Bases , Adesão Celular , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células , Materiais Revestidos Biocompatíveis/química , Proteínas do Esmalte Dentário/química , Proteínas do Esmalte Dentário/farmacologia , Ácido Glucurônico , Ácidos Hexurônicos , Hidrogéis , Cadeias alfa de Integrinas/genética , Teste de Materiais , Camundongos , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteopontina/genética , Peptídeos/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
8.
An Pediatr (Barc) ; 77(5): 323-8, 2012 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-22513392

RESUMO

INTRODUCTION: Detection of prenatal drug abuse exposure is essential to ensure an appropriate monitoring of affected children. A maternal questionnaire is not an efficient screening tool. The usefulness of maternal hair and meconium as biological materials to assess this exposure has been described in last few years. The aim of this study was to compare both these alternative biological materials for prenatal drug exposure detection in the third trimester of pregnancy, in order to assess its use as a screening tool. PATIENTS AND METHODS: Between January and March 2010, samples of maternal hair and meconium from 107 mother-infant dyads were collected in Can Misses Hospital, Ibiza. The presence of opiates, cocaine, cannabis, and amphetamines, was determined in both materials, using standard chromatographic techniques. RESULTS: Maternal hair analysis showed a 15.9% positivity for drugs of abuse (17 cases): 11 cannabis, 7 cocaine, 1 cannabis and ecstasy, and 1 cannabis and cocaine. Only one mother reported cannabis consumption and another one, cocaine. Of the 7 cocaine positive cases in hair, 6 were confirmed in meconium analysis, while of 11 cannabis positive cases, only 3 were confirmed in meconium. Two different consumer profiles were defined: cocaine consumers and cannabis consumers (with only 2 cases of multiple drug use). The highest level of cocaine ever published was detected (1.582ng/g) in one case. DISCUSSION: This study reveals a high prevalence of drug abuse in this cohort during pregnancy. Improved screening methods may optimize prevention and monitoring of exposed infants. Maternal hair seems to be more sensitive than meconium to detect prenatal exposure to cannabis during the third trimester, so it might become a good screening tool.


Assuntos
Cabelo/química , Drogas Ilícitas/análise , Mecônio/química , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Adulto , Anfetaminas/análise , Analgésicos Opioides/análise , Canabinoides/análise , Cocaína/análise , Feminino , Humanos , Gravidez , Terceiro Trimestre da Gravidez
9.
Diabet Med ; 26(11): 1156-64, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19929995

RESUMO

AIMS: The study objectives were to evaluate the pharmacokinetic and pharmacodynamic properties, as well as safety and tolerability, of single doses of taspoglutide, a human glucagon-like peptide-1 (GLP-1) analogue. METHODS: In a double-blind, placebo-controlled study, 48 patients with Type 2 diabetes [mean age 56 +/- 7 years; mean body mass index (BMI) 30.4 +/- 3.0 kg/m(2)] inadequately controlled with metformin (< or = 2 g/day) were enrolled in three sequential cohorts; 12 patients in each cohort were randomized to a single subcutaneous injection of taspoglutide (1, 8 or 30 mg) and four received placebo. RESULTS: Plasma concentrations peaked within 24 h after injection and were sustained for > or = 14 days with all doses. In comparison with placebo, the 8- and 30-mg doses of taspoglutide significantly reduced glycaemic parameters, including 24-h blood glucose and 5-h postprandial glucose areas under the curve (AUCs), for up to 14 days with the 30-mg dose (P < 0.001). The most common adverse events, primarily gastrointestinal in nature, were dose-dependent and transient. CONCLUSIONS: A single dose of taspoglutide significantly improved glycaemic parameters in Type 2 diabetes patients for up to 14 days. The formulation was well tolerated and appears suitable for weekly administration.


Assuntos
Preparações de Ação Retardada/administração & dosagem , Diabetes Mellitus Tipo 2/tratamento farmacológico , Peptídeo 1 Semelhante ao Glucagon/administração & dosagem , Hipoglicemiantes/administração & dosagem , Peptídeos/administração & dosagem , Preparações de Ação Retardada/farmacocinética , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Peptídeo 1 Semelhante ao Glucagon/farmacocinética , Humanos , Hipoglicemiantes/farmacocinética , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Peptídeos/farmacocinética , Resultado do Tratamento
10.
Interciencia ; 33(5): 359-364, mayo 2008. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: lil-493205

RESUMO

Los marcadores moleculares representan una herramienta de gran precisión para la evaluación de la diversidad genética y la determinación de la identidad de variedades, especialmente en cultivos de estrecha base genética tales como el arroz. El objetivo de este estudio fue evaluar la diversidad genética de variedades de arroz venezolanas y de líneas élites provenientes del Plan Nacional de Mejoramiento Genético de Arroz (INIA y otras instituciones), de la Fundación Danac de Productores Asociados Chispa, usando cinco combinaciones de iniciadores AFLP. Además se incluyeron dos arroces rojos. Se registraron 220 bandas desde 25 a >300pb, de las que 60 (27,27 por ciento) resultaron polimórficas, con promedio de 12 bandas por combinación. El índice de diversidad de Shannon para cada combinación varió de 0,17 a 0,41 con promedio de 0,29 ±0,10. Dicho índice mostró un moderado nivel de polimorfismo genético entre las variedades, líneas élites y arroz rojo. El análisis de agrupamiento permitió identificar cinco grupos, a una distancia de ~0,50 unidades ultramétricas. El primer grupo quedó conformado solo por arroces rojos; los grupos restantes estuvieron constituidos tanto por variedades como por líneas experimentales avanzadas. Las combinaciones AFLP permitieron la diferenciación de todos los materiales, observándose asociación entre los agrupamientos generados y la combinación genética de los genotipos. Este trabajo corrobora la utilidad de los AFLP como herramienta para discriminar entre individuos altamente emparentados.


Assuntos
Variação Genética , Biomarcadores , Oryza , Bioquímica , Química Agrícola , Venezuela
11.
Clin Endocrinol (Oxf) ; 63(5): 514-9, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16268802

RESUMO

OBJECTIVE: To investigate the pharmacokinetic profile of a prolonged release, aqueous Autogel formulation of the somatostatin analogue lanreotide (Lan-ATG). DESIGN: A phase II, randomized, double-blind study, during which patients received 60, 90 or 120 mg Lan-ATG for four fixed administrations at 28-day intervals. PATIENTS: A total of 18 patients with acromegaly were recruited; six patients were randomized to each treatment. MEASUREMENTS: Lanreotide minimum concentration (C(min)), maximum serum concentration (C(max)) and area under the concentration-time curve during a dosing interval (AUC(tau)) were assessed after a single dose and at steady state (ss). Serum GH and IGF-1 levels were assessed before each administration and at the end of the study. RESULTS: After a single administration, dose proportionality for C(min,1), C(max) and AUC(tau) was demonstrated statistically. After repeated administrations, Lan-ATG exhibited linear pharmacokinetics over the dose range and ss values of C(min), C(max) and AUC(tau) increased in a dose-dependent, linear manner. Mean C(max,ss) values were only two- to fourfold greater than C(min,ss) values, and there was good control over the entire release profile. Serum levels of GH and IGF-1 declined over the course of the study and acromegaly symptoms improved. The treatment was well tolerated. CONCLUSIONS: Lan-ATG showed linear pharmacokinetic profiles over the three dose levels after both single and repeated dosing, no initial burst effect and good control over the entire release profile. Despite the absence of dose adaptation, four injections of Lan-ATG were effective in lowering serum levels of GH and IGF-1.


Assuntos
Acromegalia/metabolismo , Antineoplásicos/farmacocinética , Peptídeos Cíclicos/farmacocinética , Somatostatina/análogos & derivados , Acromegalia/tratamento farmacológico , Adulto , Análise de Variância , Antineoplásicos/uso terapêutico , Preparações de Ação Retardada , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Géis , Hormônio do Crescimento/sangue , Humanos , Injeções Subcutâneas , Fator de Crescimento Insulin-Like I/análise , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Peptídeos Cíclicos/uso terapêutico , Somatostatina/farmacocinética , Somatostatina/uso terapêutico
12.
Clin Endocrinol (Oxf) ; 59(4): 476-81, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14510910

RESUMO

OBJECTIVE: Given the important role of the beta2-adrenoceptor (beta2-AR) in lipid mobilization and the lack of studies in Southern European countries, the aim of this study was to investigate the role of the glutamine 27 glutamic acid (Gln27Glu) beta2-AR polymorphism in the susceptibility to obesity and its metabolic complications in a population-based nationwide multicentre study in Spain, especially focusing on the hypothetical influence of gender. DESIGN: Cross-sectional population-based study. PATIENTS: We studied 666 nonrelated adults (47.9% men and 52.1% women), aged 35-64 years, chosen randomly from a nationwide population-based survey of obesity, and related conditions including insulin resistance and cardiovascular risk factors. MEASUREMENTS: Body mass index (BMI), waist-to-hip ratio (WHR), sagittal abdominal diameter (SAD), systolic and diastolic blood pressure, fasting and 2-h post-glucose load glycaemic levels, total cholesterol, high density lipoprotein (HDL)- and low density lipoprotein (LDL)-cholesterol, triglycerides, insulin, proinsulin and leptin plasma levels were measured. Beta2-AR Gln27Glu genotypes were determined by restriction fragment length polymorphism (RFLP)-polymerase chain reaction (PCR). RESULTS: Glu27 homozygous obese men had significantly higher BMI and SAD mean values than both heterozygous and Gln27 homozygous obese men. Two-hour post-load plasma glucose concentration was higher in Glu27 homozygous than in Gln27 homozygous in the whole population and only in men when stratified by gender. No differences according to the genotype were found for the rest of the parameters studied, including homeostasis model assessment (HOMA), insulin, proinsulin and leptin levels, but for total and LDL-cholesterol these increased in men. We did not find differences in the anthropometrical and biochemical parameters according to the genotype in women. Multivariate logistic regression analysis showed that Glu27 homozygosity after adjustment for SAD was associated with type 2 diabetes mellitus. CONCLUSIONS: Our results suggest that the glutamic acid 27 allele of the beta2-adrenoceptor may be a risk factor in men but not in women for the accumulation of visceral fat and for its association with the development of type 2 diabetes mellitus.


Assuntos
Glicemia/análise , Ácido Glutâmico/genética , Glutamina/genética , Insulina/sangue , Obesidade/genética , Polimorfismo de Fragmento de Restrição , Receptores Adrenérgicos beta 2/genética , Adulto , Constituição Corporal , Índice de Massa Corporal , Estudos Transversais , Diabetes Mellitus Tipo 2/genética , Feminino , Genótipo , Teste de Tolerância a Glucose/métodos , Humanos , Leptina/sangue , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Receptores Adrenérgicos , Fatores Sexuais
13.
Nutr Hosp ; 17 Suppl 1: 23-33, 2002 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-11928533

RESUMO

The prevalence of obesity has increased to an extraordinary degree, especially over the last three decades, so that if these trends persist, practically all of the adult population would be obese in the course of only two generations. On the basis of family and adoption studies, it has been estimated that the genetic component in obesity ranges from 20% to 80%. Thus, the most common forms of obesity would depend on the interaction of multiple genes as well as on the influence of various environmental factors, such as eating behaviour and lifestyle. Although none of these genes potentially involved in the control of body weight seems to be directly responsible for the syndrome, there have been reports of interesting associations between polymorphisms of certain candidate genes and obesity or its metabolic complications. The studies into associations between genotypes and obese phenotype have increased over the last few years and have basically focussed on the genes involved in the control of the energy balance, giving rise to a whole series of results which might constitute the basis for extremely interesting strategies for the prevention and treatment of this serious problem.


Assuntos
Obesidade/genética , Obesidade/terapia , Polimorfismo Genético , Humanos , Obesidade/etiologia , Obesidade/prevenção & controle , Fenótipo
14.
Cell Mol Life Sci ; 59(11): 1960-71, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12530526

RESUMO

The aim of this study was to identify candidate genes for visceral obesity by screening for genes strongly differentially expressed between human subcutaneous and visceral adipose depots. A cDNA microarray with human adipose-derived cDNAs was used as an initial screening to identify genes that are potentially differentially expressed between human subcutaneous and visceral abdominal fat tissues. For the two best candidates, carboxypeptidase E (CPE) and thrombospondin-1 (THBS1) (EST N72406), real-time RT-PCR was performed to confirm their depot specific expression in extremely obese individuals. Both genes appeared to be strongly differentially expressed, having a higher expression in the visceral depot than in the subcutaneous one. For THBS1, the difference in expression between the depots was greater in women than in men. The involvement of CPE and THBS1 in obesity allows us to suggest that the physiological processes controlled by these genes contribute to depot and gender-related differences in the metabolic complications of obesity.


Assuntos
Adipócitos/metabolismo , Carboxipeptidases/genética , Obesidade Mórbida/genética , Trombospondina 1/genética , Tecido Adiposo/metabolismo , Carboxipeptidase H , Carboxipeptidases/biossíntese , Feminino , Humanos , Masculino , Obesidade Mórbida/etiologia , Obesidade Mórbida/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Omento/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tela Subcutânea/metabolismo , Trombospondina 1/biossíntese
15.
J Med Chem ; 44(18): 3001-13, 2001 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-11520209

RESUMO

This paper describes the synthesis of a series of azo compounds able to deliver 5-aminosalicylic acid (5-ASA) and a potent platelet activating factor (PAF) antagonist in a colon-specific manner for the purpose of treating ulcerative colitis. We found it possible to add an amino group on the aromatic moiety of our reported 1-[(1-acyl-4-piperidyl)methyl]-1H-2-methylimidazo[4,5-c]pyridine derivatives or on British Biotech compounds BB-882 and BB-823 maintaining a high level of activity as PAF antagonist. A selected compound UR-12715 (49c) showed an IC(50) of 8 nM in the in vitro PAF-induced aggregation assay, and an ID(50) of 29 microg/kg in the in vivo PAF-induced hypotension test in normotensive rats. Through attachment of 49c to the 5-ASA via azo functionality we obtained UR-12746 (70). Pharmacokinetics experiments with [14C]-70 allow us to reach the following conclusions, critical in the design of these new prodrugs of 5-ASA. Neither the whole molecule 70 nor the carrier 49c were absorbed after oral administration of [14C]-70 in rat as was demonstrated by the absence of plasma levels of radioactivity and the high recovery of it in feces. Effective cleavage of azo bond (84%) by microflora in the colon is achieved. These facts ensure high topical concentrations of 5-ASA and 49c in the colon. Additionally, 70 exhibited a potent anticolitic effect in the trinitrobenzenesulfonic acid-induced colitis model in the rat. This profile suggests that UR-12746 (70) provides an attractive new approach to the treatment of ulcerative colitis.


Assuntos
Anti-Inflamatórios não Esteroides/síntese química , Compostos Aza/síntese química , Compostos Azo/síntese química , Imidazóis/síntese química , Mesalamina/química , Mesalamina/síntese química , Fator de Ativação de Plaquetas/antagonistas & inibidores , Pró-Fármacos/síntese química , Piridinas/síntese química , Aminas/síntese química , Aminas/química , Aminas/farmacologia , Ácidos Aminossalicílicos , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacocinética , Anti-Inflamatórios não Esteroides/farmacologia , Compostos Aza/química , Compostos Aza/farmacologia , Compostos Azo/química , Compostos Azo/farmacocinética , Compostos Azo/farmacologia , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos , Feminino , Hipotensão/tratamento farmacológico , Imidazóis/química , Imidazóis/farmacologia , Masculino , Mesalamina/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Pró-Fármacos/química , Pró-Fármacos/farmacocinética , Pró-Fármacos/farmacologia , Piridinas/química , Piridinas/farmacologia , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Estereoisomerismo , Relação Estrutura-Atividade , Ácido Trinitrobenzenossulfônico
16.
J Cardiovasc Pharmacol ; 35(3): 383-9, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10710122

RESUMO

This study was conducted to assess the pharmacologic properties of the new orally active angiotensin II subtype I (AT1) antagonist UR-7247, a product with a half-life >100 h in humans. The experiment was designed as an open-label, single-dose administration study with four parallel groups of four healthy men receiving increasing single oral doses (2.5, 5, and 10 mg) of UR-7247 or losartan, 100 mg. Angiotensin II receptor blockade was investigated < or =96 h after drug intake, with three independent methods [i.e., the inhibition of blood pressure (BP) response to exogenous Ang II, an in vitro Ang II-receptor assay (RRA), and the reactive increase in plasma angiotensin II. Plasma drug levels also were measured. The degree of blockade observed in vivo was statistically significant < or = 96 h with all UR-7247 doses for diastolic BP (p < 0.05) and < or =48 h for systolic BP. The maximal inhibition achieved with 10 mg UR-7247 was measured 6-24 h after drug intake and reached 54 +/- 17% and 48 +/- 20% for diastolic and systolic responses, respectively. Losartan, 100 mg, induced a greater short-term AT1-receptor blockade than 2.5- and 5.0-mg doses of UR-7247 (p < 0.001 for diastolic BP), but the UR-7247 effect was longer lasting. In vivo, no significant difference was observed between 10 mg UR-7247 and 100 mg losartan 4 h after drug intake, but in vitro, the blockade achieved with 100 mg losartan was higher than that seen with UR-7247. Finally, the results confirm that UR-7247 has a very long plasma elimination half-life, which may be due to a high but also tight binding to protein binding sites. In conclusion, UR-7247 is a long-lasting, well-tolerated AT1 receptor in healthy subjects.


Assuntos
Antagonistas de Receptores de Angiotensina , Pirazóis/farmacologia , Administração Oral , Adulto , Angiotensina II/sangue , Angiotensina II/metabolismo , Anti-Hipertensivos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Losartan/farmacologia , Masculino , Pirazóis/administração & dosagem , Pirazóis/sangue , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina
17.
Arzneimittelforschung ; 48(5): 512-7, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9638320

RESUMO

In order to improve the effectiveness of treatment of vaginal yeast infections, flutrimazole, (CAS 119006-77-8), a broad spectrum local imidazolic fungicide, has been formulated in an advanced delivery system (Site Release, here in after briefly referred to as SR) designed to improve vaginal retention of the drug. To determine the extent of absorption of 14C-flutrimazole from this formulation, the absorption and excretion of total radioactivity have been studied in healthy postmenopausal female volunteers after intravaginal administration of approximately 5 g of SR Vaginal Cream containing 2% 14C-flutrimazole. Concentrations of unchanged flutrimazole have also been measured in plasma and urine, using a validated gas chromatography-mass spectrometry method. The rate of absorption was slow, with a mean peak plasma radioactivity concentration, Cmax, of 56 ng equivalents/ml, achieved at a mean Tmax of 28 h. Corresponding parameters for flutrimazole were 1.94 ng/ml at 24 h. At 24 h post-dose, unchanged flutrimazole represented only 3% of plasma total radioactivity which indicates that flutrimazole is extensively metabolised in man. Total radioactivity and unchanged flutrimazole were eliminated from plasma with terminal half-lives of 37 and 22 h, respectively. From the proportion of the radioactive dose excreted in urine and faeces, the maximal extent of absorption indicated for the intravaginal dose was about 8%, which is similar to that observed with other imidazolic compounds administered by this route. Thus, the formulation achieves the aim of prolonged drug action through the maintenance of therapeutic concentrations of the drug at the site of infection without notably increased absorption.


Assuntos
Antifúngicos/farmacocinética , Clotrimazol/análogos & derivados , Absorção , Idoso , Antifúngicos/administração & dosagem , Clotrimazol/administração & dosagem , Clotrimazol/farmacocinética , Fezes/química , Feminino , Meia-Vida , Humanos , Pessoa de Meia-Idade , Pós-Menopausa , Cremes, Espumas e Géis Vaginais
18.
J Med Chem ; 41(11): 1855-68, 1998 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-9599236

RESUMO

A series of 92 azole antifungals containing an amido alcohol unit was synthesized. The nature and substitution of the amide portion was systematically modified in search of improved antifungal activity, especially against filamentous fungi. The compounds were tested in vitro against a variety of clinically important pathogens and in vivo (po) in a murine candidosis model. Thiazole and thiophene carboxamides carrying both a substituted phenyl ring and a small alkyl group were best suited for activity against filamentous fungi. In a subset of these compounds, the amide portion was conformationally locked by means of a pyrimidone ring and it was proven that only an orthogonal orientation of the phenyl ring yields bioactive products. A tendency to display long plasma elimination half-lives was observed in both series. Two compounds, 74 and 107, representative of the open and cyclic amides, respectively, were chosen for further studies, based on their excellent activity in in vivo murine models of candidosis and aspergillosis. This work describes the SARs found within this series. The next paper displays the results obtained in a related series of compounds, the quinazolinones.


Assuntos
Antifúngicos , Pirimidinonas , Tiazóis , Tiofenos , Triazóis , Animais , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacocinética , Antifúngicos/farmacologia , Aspergilose/tratamento farmacológico , Aspergillus fumigatus , Candidíase/tratamento farmacológico , Contagem de Colônia Microbiana , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Masculino , Camundongos , Conformação Molecular , Pirimidinonas/síntese química , Pirimidinonas/química , Pirimidinonas/farmacocinética , Pirimidinonas/farmacologia , Ratos , Estereoisomerismo , Relação Estrutura-Atividade , Tiazóis/síntese química , Tiazóis/química , Tiazóis/farmacocinética , Tiazóis/farmacologia , Tiofenos/síntese química , Tiofenos/química , Tiofenos/farmacocinética , Tiofenos/farmacologia , Triazóis/síntese química , Triazóis/química , Triazóis/farmacocinética , Triazóis/farmacologia
19.
J Med Chem ; 41(11): 1869-82, 1998 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-9599237

RESUMO

A series of azole antifungal agents featuring a quinazolinone nucleus have been subjected to studies of structure-activity relationships. In general, these compounds displayed higher in vitro activities against filamentous fungi and shorter half-lives than the structures described in our preceding paper. The most potent products in vitro carried a halogen (or an isostere) at the 7-position of the quinazolinone ring. Using a murine model of systemic candidosis, oral activity was found to be dependent on hydrophobicity, which, in turn, modulated the compound's half-life. The 7-Cl derivative, (1R,2R)-7-chloro-3-[2-(2, 4-difluorophenyl)-2-hydroxy-1-methyl-3-(1H-1,2, 4-triazol-1-yl)propyl]quinazolin-4(3H)-one (20, UR-9825), was selected for further testing due to its high in vitro activity, low toxicity, good pharmacokinetic profile, and ease of obtention. Compound 20 is the (1R,2R) isomer of four possible stereoisomers. The other three isomers were also prepared and tested. The enantiomer (1S,2S) and the (1R,2S) epimer were inactive, whereas the (1S,2R) epimer retained some activity. In vitro 20 was superior to fluconazole, itraconazole, SCH-42427, and TAK-187 and roughly similar to voriconazole and ER-30346. In vivo, 20 was only moderately active in a mouse model of systemic candidosis when administration was limited to the first day. This was attributed to its short half-life in that species (t1/2 = 1 h po). Protection levels comparable to or higher than those of fluconazole, however, were observed in systemic candidosis models in rat and rabbit, where the half-life of the compound was found to be 6 and 9 h, respectively. Finally, 20 showed excellent protection levels in an immunocompromised rat model of disseminated aspergillosis. The compound showed low toxicity signs when administered to rats at 250 mg/kg qd or at 100 mg/kg bid during 28 days.


Assuntos
Antifúngicos , Quinazolinas , Triazóis , Animais , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacocinética , Antifúngicos/farmacologia , Aspergilose/tratamento farmacológico , Aspergillus fumigatus , Candidíase/tratamento farmacológico , Contagem de Colônia Microbiana , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Masculino , Camundongos , Conformação Molecular , Quinazolinas/síntese química , Quinazolinas/química , Quinazolinas/farmacocinética , Quinazolinas/farmacologia , Coelhos , Ratos , Ratos Sprague-Dawley , Estereoisomerismo , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/química , Triazóis/farmacocinética , Triazóis/farmacologia
20.
Arzneimittelforschung ; 47(10): 1139-44, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9368709

RESUMO

Flutrimazole (1-[(2-fluorophenyl)(4-fluorophenyl)phenylmethyl]-1 H-imidazole, CAS 119006-77-8, UR-4056) is a new wide spectrum local imidazolic antifungal agent that has already been formulated as a dermal cream (FDC). A comparative study was carried out of the release of flutrimazole from two emulsions in which the drug has been incorporated differently: one dissolved in the oily phase (E24) and the other dispersed in the aqueous formulation phase (E25). Based on the E25 formulation, two more dermal creams were prepared, E27 with benzyl alcohol and E28 with diazolidinyl urea as preservative agents. A comparative study of transdermal penetration including E27, E28, FDC (reference 1% flutrimazole dermal cream) and 1% flutrimazole hydroalcoholic solution was also performed. An amount of the sample dosage form containing 10 mg of flutrimazole was applied to a Franz type cell. The penetration membrane used was cellulose acetate in the release studies and human skin provided by a plastic surgery clinic in the transdermal penetration study. The amount released after 7 h was 36.3 +/- 4.9 micrograms when flutrimazole was dissolved (E24) and 35.9 +/- 5.3 micrograms when flutrimazole was dispersed (E25). Although the differences were not significant, the cream with dispersed flutrimazole was selected for further penetration studies due to its better stability observed in previous studies. The amounts of drug penetrated after 44 h were 31.3, 41.5, 38.3 and 186.5 micrograms for E27, E28, FDC dermal creams and topical hydroalcoholic solution, respectively. The solution showed a statistically significant difference (p < 0.05) from the other formulations, however, no differences were observed between the dermal cream formulations. No differences were neither obtained between the different dermal creams when the amount of drug retained in the skin was compared. This allows to assert that the excipients used do not have different influences on transdermal penetration. In all cases, the mean quantity penetrated in relation to the dose applied was at most 0.5%. These results allow to infer that flutrimazole shows scarce transdermal penetration. Further, the amount of flutrimazole retained per gram of skin is more than 100 times the MIC per gram obtained in previous in vitro studies. It may be assumed that the topical application of the new formulations assayed would allow to obtain a good therapeutic response.


Assuntos
Antifúngicos/química , Antifúngicos/farmacocinética , Clotrimazol/análogos & derivados , Administração Cutânea , Cromatografia Líquida de Alta Pressão , Clotrimazol/química , Clotrimazol/farmacocinética , Difusão , Humanos , Técnicas In Vitro , Pomadas , Absorção Cutânea/fisiologia , Solubilidade
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