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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.
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
4.
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
5.
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
6.
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
7.
Eur J Pharmacol ; 147(3): 459-63, 1988 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-3163974

RESUMO

The effect of fosfosal, a non-acetylated salicylic acid derivative, on the content of prostaglandin E2 (PGE2) and the migration of polymorphonuclear leukocytes in inflammatory exudates induced by s.c. implantation of 0.5% carrageenan soaked sponges in rats has been determined. Fosfosal, which does not inhibit PG synthesis in vitro, is capable of reducing, in a dose-dependent manner, the PGE2 content of the exudates, with a maximum reduction of 50-60% at a total dose of 100 mg/kg i.p. Acetylsalicylic acid was slightly more potent (68% reduction, 2 x 50 mg/kg i.p.). Six hours after fosfosal administration, salicylic acid, the principal metabolite of fosfosal, accumulated in the exudates at concentrations of about 100 micrograms/ml. These concentrations were sufficient to inhibit PG synthetase activity in vitro. Neither fosfosal nor acetylsalicyclic acid affected polymorphonuclear leukocyte migration at doses which significantly reduced the concentrations of PGE2. Indomethacin, used as reference, reduced leukocyte migration by 28 and 45% at a dose of 1 and 10 mg/kg i.p. respectively. The results indicate that fosfosal, in spite of its lack of effect on PG biosynthesis in vitro, exerts an effect on the inflammatory locus in vivo which may account, at least in part, for its anti-inflammatory activity. Moreover, our results confirm that the inhibition of PG synthesis and leukocyte migration are mediated by different mechanisms.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Aspirina/farmacologia , Inibição de Migração Celular , Inflamação/metabolismo , Neutrófilos/imunologia , Organofosfatos/farmacologia , Compostos Organofosforados/farmacologia , Prostaglandinas E/metabolismo , Animais , Dinoprostona , Indometacina/farmacologia , Inflamação/imunologia , Masculino , Neutrófilos/efeitos dos fármacos , Ratos , Ratos Endogâmicos
8.
J Pharm Sci ; 82(11): 1126-9, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8289126

RESUMO

Usually, smaller mammals have higher clearances per unit body mass than do larger mammalian species. When clearance and other pharmacokinetic parameters are correlated with internal physiological processes, species tend to dispose of drugs at a similar pace. The first application of this concept is pharmacokinetic time, expressed with different units: Kallynochron, Apolysichron, Dienetichron, and Syndesichron. The present work describes pharmacokinetic time in these units from data obtained with propafenone in eight animal species: mouse, rat, rabbit, dog, sheep, human, cow, and horse. Additionally, volume of distribution (Vdss = 6.5 B0.94) and clearance (CL = 0.17 B0.86) were correlated to body weight (B). Different units of pharmacokinetic time were evaluated with an Akaike Information Criterion test, and the Syndesichron was the unit that provided the best superimposition for the concentration-time plot for all animal species. It can be inferred that all mammalian species eliminated half of the dose from their bodies in 4759 Syndesichrons.


Assuntos
Propafenona/farmacocinética , Adulto , Animais , Bovinos , Cães , Feminino , Cavalos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C3H , Coelhos , Ratos , Ovinos , Especificidade da Espécie
9.
J Pharm Pharmacol ; 44(11): 935-7, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1361542

RESUMO

2-Hydroxy-4-trifluoromethylbenzoic acid (HTB) is the main active metabolite of triflusal, an antiplatelet drug. The in-vitro binding of HTB to human serum was studied in the presence of different drugs. The results indicate that no statistically significant changes are observed in the HTB binding in the presence of caffeine, theophylline, glisentide, enalapril, cimetidine or warfarin. The free fraction of HTB increases significantly in the presence of the non-steroidal anti-inflammatory drugs studied: diclofenac, ibuprofen, indomethacin, naproxen, piroxicam and salicylic acid. At high concentrations, HTB displaces these anti-inflammatory drugs and also glisentide and warfarin from their protein binding sites.


Assuntos
Inibidores da Agregação Plaquetária/farmacocinética , Salicilatos/farmacocinética , Anti-Inflamatórios não Esteroides/farmacologia , Ligação Competitiva/efeitos dos fármacos , Interações Medicamentosas , Humanos , Ligação Proteica , Albumina Sérica/metabolismo
10.
Avian Dis ; 26(1): 107-17, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-7092735

RESUMO

A single phenylhydrazine injection (1.8 mg/kg body weight in chickens and 2.2 mg/kg body weight in pigeons) was administered intramuscularly to different lots of animals. The modification of hematocrit, hemoglobin, erythrocyte number, reticulocyte concentration, plasma iron, and total iron-binding capacity was monitored versus time. Depression of the hematological parameters in chickens was greatest on the second day (27-40%), and the values returned to normal by day 7. The drop in pigeons was greater (28-51%) and took longer to return to normal (day 22). The highest percentage of reticulocytes was 35-37%. A plasma iron increase was concomitant to cell destruction and decreased later. The plasma iron clearance values showed a double slope line as a result of the presence of reticulocytes. A high correlation existed between iron uptake by red blood cells at 5 min and the reticulocyte concentration. The responses of the two species to the phenylhydrazine were similar, and differences were more quantitative than qualitative. Reticulocytes were present in normal pigeons, which introduces an important variant in iron metabolism in birds.


Assuntos
Anemia/sangue , Galinhas/sangue , Columbidae/sangue , Ferro/sangue , Fenil-Hidrazinas/efeitos adversos , Anemia/induzido quimicamente , Animais , Contagem de Eritrócitos/veterinária , Hematócrito/veterinária , Hemoglobinas/metabolismo , Fenil-Hidrazinas/administração & dosagem , Reticulócitos/citologia , Especificidade da Espécie
11.
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
12.
Eur J Drug Metab Pharmacokinet ; 16(4): 261-8, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1823869

RESUMO

The methods for determining plasma concentrations of triflusal (2-acetoxy-4-trifluoromethyl benzoic acid) that have been described, do not distinguish between the drug and its main metabolite HTB (2-hydroxy-4-trifluoromethyl benzoic acid). In the present study, we have developed a new analytical technique based on HPLC that enabled us to carry out a pharmacokinetic study of the drug and its metabolite in animals. An intravenous or oral dose of 50 mg/kg was administered to male Sprague-Dawley rats, and 15 mg/kg was administered to beagle dogs. Plasma levels of triflusal and HTB were determined. In rats, triflusal was quickly eliminated from plasma with a biological half-life (t1/2) of 2.7 min and a clearance (Cl) of 73.4 (ml/kg)/min. The elimination of HTB was much slower with a t1/2 of 21.5 h and a Cl of 5.1 (mg/kg)/h. The maximum concentration (Cmax) of triflusal in rats after an oral administration was 8.1 +/- 2.0 micrograms/ml reached between 2.5 and 10 min. The Cmax of HTB was 237.7 micrograms/ml and was achieved at 0.7 h. The bioavailability of triflusal in rats was only 10.6% while the bioavailability of HTB was more than 100% indicating an important first pass effect. In dogs the t1/2 of triflusal was 14.4 +/- 5.9 min and the Cl was 25.1 +/- 4.7 (ml/kg)/min. HTB was also eliminated very slowly with a t1/2 of 71.1 +/- 12.5 h and a Cl of 2.4 +/- 0.3 (ml/kg)/h. The Cmax of triflusal in dogs was 13.3 +/- 2.9 micrograms/ml and was reached after 19.2 +/- 6.1 min (tmax).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Salicilatos/farmacocinética , Administração Oral , Animais , Cromatografia Líquida de Alta Pressão , Cães , Feminino , Meia-Vida , Hidrólise , Injeções Intravenosas , Masculino , Ratos , Ratos Endogâmicos , Salicilatos/metabolismo
13.
Eur J Drug Metab Pharmacokinet ; 16(4): 269-73, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1823870

RESUMO

The pharmacokinetic profile of triflusal (2-acetoxy-4-trifluoromethyl benzoic acid) and its main metabolite HTB (2-hydroxy-4-trifluoromethyl benzoic acid) has been studied in 8 healthy subjects (4 males and 4 females), after a single oral dose of 900 mg of triflusal. Plasma concentrations were determined by a sensitive HPLC method. Sampling was performed up to 120 h post medication. Triflusal displays a Cmax of 11.6 +/- 1.7 micrograms/ml and a tmax of 0.88 +/- 0.26 h. The elimination half-life (t1/2) was 0.55 h with a clearance (Cl/F) of 45.5 +/- 11.0 l/h. HTB kinetic parameters were: tmax 4.96 +/- 1.37 h and Cmax 92.7 +/- 17.1 micrograms/ml, with an elimination t1/2 of 34.3 +/- 5.3 and a clearance of 0.18 +/- 0.04 l/h. The results obtained in this study show a rapid absorption of triflusal and an immediate biotransformation into HTB. The long lasting platelet anti-aggregatory effect of triflusal in spite of its short t1/2, could be explained by the irreversible inhibition of platelet cyclo-oxygenase and the sustained levels of HTB, which also possess anti-aggregant properties.


Assuntos
Inibidores da Agregação Plaquetária/farmacocinética , Salicilatos/farmacocinética , Administração Oral , Adulto , Biotransformação , Cromatografia Líquida de Alta Pressão , Feminino , Meia-Vida , Humanos , Masculino , Inibidores da Agregação Plaquetária/administração & dosagem , Salicilatos/administração & dosagem
14.
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
15.
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
16.
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 , Alicerces Teciduais/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
17.
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
18.
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
19.
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
20.
Q J Exp Physiol Cogn Med Sci ; 63(4): 383-93, 1978 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-253379

RESUMO

Several haematological parameters such as haemoglobin concentration, haematocrit, erythrocyte number, reticulocyte concentration, plasma iron and total iron binding capacity were determined in 118 urban pigeons of both sexes. No statistically significant sex differences among these parameters were found. In 36 specimens (23 males and 13 females), the plasma iron turnover was determined using 59Fe. The results obtained in this species, expressed per 100 ml-1 blood. day-1 and Kg-1 body weight. day-1, were compared with those of turkeys, ducks and chickens calculated from earlier papers. The highest values versus body weight were observed in pigeons. Organ (liver, spleen, tibia, heart, leg muscle, ribs, sternal keel, gonads and blood) distribution of 59Fe intravenous injection was analyzed during a period from 5 min up to 120 days (19 different times) in groups of 4 pigeons. At the 6 h period, the organs retained the highest dose (20% of total Fe injected), but by the 2nd day period, the radioiron in the blood represented about 98% of the total injected. A fast iron uptake by the circulatory blood was checked and compared with that of other species (domestic fowl, ducks and turkeys). The reticulocyte count in pigeons normally ranged from 4 to 12%, which was consistent with these results. A linear decreasing radioactivity in blood, with an inflexion point on the 40th day was observed. An inverse correspondence between blood and liver was found. Content in other organs decreased uniformly with time, except the heart where the iron content was practically constant during the whole time. Ribs and sternal keel are erythropoietic organs in young pigeons.


Assuntos
Columbidae/metabolismo , Ferro/metabolismo , Animais , Contagem de Eritrócitos , Feminino , Hematócrito , Hemoglobinas/metabolismo , Ferro/sangue , Masculino , Reticulócitos/citologia , Fatores Sexuais , Fatores de Tempo , Distribuição Tecidual
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