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Medicinas Complementares
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1.
Homeopathy ; 109(1): 3-13, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31454832

RESUMO

BACKGROUND: This research aimed to observe the effect of homeopathically prepared Vibrio parahaemolyticus (ViP) and V. alginolyticus (ViA) and the commercial homeopathic compound Similia (Phosphoricum acidum and Silicea terra) on the digestive enzyme activities of Seriola rivoliana juveniles under usual culture conditions. MATERIALS AND METHODS: Biochemical analysis was used to study the effect of highly diluted substances (7C potency) prepared from ViP and ViA (Treatment 1: T1) and the homeopathic compound Phosphoricum acidum and Silicea terra (Treatment 2: T2) on changes in the main digestive enzymes on weaning-state fish (WS; 30 days post-hatching [DPH]) and early juveniles (EJ; 62 DPH) versus a reference control group that received no homeopathic medicines. RESULTS: Treatment T2 significantly increased the activity of trypsin and lipase and decreased the activity of amylase, whereas treatment T1 increased the activity of chymotrypsin and reduced the activity of aminopeptidase-N in WS fish. Except for alkaline phosphatase, which was significantly reduced in the intestine, no significant differences in enzymatic activity were found between treated EJ fish and controls. The fish of the WS group had a higher growth rate with the T2 treatment. CONCLUSIONS: T1 treatment stimulated chymotrypsin in EJ fish and T2 promoted intestinal maturation of WS fish. Higher growth rate with the T2 treatment may be associated with the stimulation of trypsin activity. Thus, T2 may be applied, under hatchery conditions, during larval stages with an aim to enhance digestion and assimilation of inert food.


Assuntos
Trato Gastrointestinal/enzimologia , Homeopatia/métodos , Ácidos Fosfóricos/farmacologia , Dióxido de Silício/farmacologia , Vibrio/patogenicidade , Animais , Peixes
2.
J Enzyme Inhib Med Chem ; 35(1): 59-64, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31663383

RESUMO

A primary strategy to combat antimicrobial resistance is the identification of novel therapeutic targets and anti-infectives with alternative mechanisms of action. The inhibition of the metalloenzymes carbonic anhydrases (CAs, EC 4.2.1.1) from pathogens (bacteria, fungi, and protozoa) was shown to produce an impairment of the microorganism growth and virulence. As phosphonamidates have been recently validated as human α-CA inhibitors (CAIs) and no phosphorus-based zinc-binding group have been assessed to date against ß-class CAs, herein we report an inhibition study with this class of compounds against ß-CAs from pathogenic bacteria, fungi, and protozoa. Our data suggest that phosphonamidates are among the CAIs with the best selectivity for ß-class over human isozymes, making them interesting leads for the development of new anti-infectives.


Assuntos
Amidas/farmacologia , Anti-Infecciosos/farmacologia , Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Compostos Organometálicos/farmacologia , Ácidos Fosfóricos/farmacologia , Amidas/química , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Bactérias/efeitos dos fármacos , Bactérias/enzimologia , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Relação Dose-Resposta a Droga , Fungos/efeitos dos fármacos , Fungos/enzimologia , Humanos , Leishmania donovani/efeitos dos fármacos , Leishmania donovani/enzimologia , Estrutura Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Ácidos Fosfóricos/química , Fósforo/química , Fósforo/farmacologia , Relação Estrutura-Atividade , Zinco/química , Zinco/farmacologia
3.
Photodiagnosis Photodyn Ther ; 24: 228-231, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30172074

RESUMO

The aim of the study was to evaluate the effect of diode laser as a phototherapy on surface treatment of fiber post and its bond strength to resin core build-up material. In this in-vitro study fifty fiber post of 1 mm tip-diameter and 20 mm length were used. The posts were mounted and randomly divided into 5 groups (n = 10) according to different surface treatment methods i.e. Group 1: Control, Group 2: Application of 37% Phosphoric Acid, Group 3: Treated with 40% H2O2, Group 4: Sandblasted with 50 µm aluminium oxide particles and Group 5: treated with diode laser. In all specimens including control, a cylinder of resin composite around the fiber post was made. All Specimens were mounted in a universal testing machine. Push-out test was performed and bond strengths were calculated. Using analysis of variance (ANOVA) and post hoc Tukey multiple comparisons test, means of push out bond strength were compared among the study groups. The highest bond strength was shown among Sandblasted [50 µm, Aluminium Oxide (Al2O3)] group [139.86] and the lowest push-out bond strength was observed in Control specimens [75.73]. The bond strength values of fiber post treated with Diode laser [100.81] and 40% H2O2 [105.64] were comparable.


Assuntos
Resinas Compostas , Colagem Dentária , Lasers Semicondutores , Fotoquimioterapia/métodos , Prótese Dentária/microbiologia , Peróxido de Hidrogênio/farmacologia , Ácidos Fosfóricos/farmacologia , Fármacos Fotossensibilizantes , Distribuição Aleatória
4.
J Clin Pediatr Dent ; 41(4): 280-283, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28650791

RESUMO

OBJECTIVE: The aim of this study was to compare the effect of different deproteinizing agents on shear bond strength of composite to primary teeth enamel. STUDY DESIGN: Forty sound primary molars divided in 4 groups of 10 teeth each. In control group 1, enamel was etched for 60 seconds with 37% phosphoric acid and rinsed with water. Group 2: after acid etching deproteinizing agent 5 % sodium hypochlorite was applied for 60 seconds and rinsed. Group 3: after acid etching deproteinizing agent papain gel was applied for 60 seconds and rinsed. Group 4: after acid etching deproteinizing agent bromelain gel applied for 60 seconds and rinsed. Following this, bonding agent was applied to treated enamel surface and composite resin disc were build. Samples were then tested for shear bond strength using Universal Testing Machine. RESULTS: Mean SBS was highest for group 4 and lowest for group 1. No statistically significant difference (p value >0.05) was found between all the four groups. CONCLUSION: Among deproteinizing agents, deproteinization when carried out with bromelain gel and sodium hypochlorite showed effective bond strength as compared to papain.


Assuntos
Condicionamento Ácido do Dente/métodos , Bromelaínas/farmacologia , Colagem Dentária/métodos , Papaína/farmacologia , Ácidos Fosfóricos/farmacologia , Hipoclorito de Sódio/farmacologia , Humanos , Resistência ao Cisalhamento
5.
Biomed Pharmacother ; 87: 443-450, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28068635

RESUMO

Inositol hexa phosphoric acid (IP6) or Phytic acid, a natural antioxidant of some leguminous plants, known to act as a protective agent for seed storage in plants by suppressing iron catalyzed oxidative process. Following the same mechanism, we have tested the effect of IP6 on iron overloaded in vitro oxidative stress, and studied it's in vivo hepatoprotective ability in iron-dextran (injection)-induced iron overloaded liver injury in mice (intraperitoneal). Our results showed that IP6 had in vitro iron chelation (IC50 38.4µg/ml) activity, with the inhibition of iron-induced lipid peroxidation (IC50 552µg/ml), and deoxyribose sugar degrading hydroxyl radicals (IC50 448.6µg/ml). Oral administration of IP6 (0-200mg/kg) revealed significant decrease in biochemical markers such as serum iron, total iron binding, serum ferritin and serum enzymes. Histopathology of liver stained with hematoxylin-eosin and Prussian blue showed reduced hepatocellular necrosis, ballooning and inflammation, indicating the restoration of normal cellular integrity. Interestingly, the IP6 was found to down-regulate the mRNA expression of tumor necrosis factor (TNF)-α, Interleukin (IL)-1ß, and IL-6 in iron overloaded liver tissues. Thus, we provide an insight that IP6, a natural food component, can serve as an iron chelator against iron overload diseases like Thalassemia, and also as a dietary hepatoprotective supplement.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Inositol/farmacologia , Sobrecarga de Ferro/tratamento farmacológico , Ferro/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Ácidos Fosfóricos/farmacologia , Ácido Fítico/farmacologia , Animais , Antioxidantes/farmacologia , Suplementos Nutricionais , Regulação para Baixo/efeitos dos fármacos , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Sobrecarga de Ferro/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Oxirredução/efeitos dos fármacos , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
6.
Bioresour Technol ; 165: 9-12, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24630370

RESUMO

Oil palm empty fruit bunches (OPEFB), a lignocellulosic residue of palm oil industries was examined for ethanol production. Milled OPEFB exposed to simultaneous saccharification and fermentation (SSF) with enzymes and Saccharomyces cerevisiae resulted just in 14.5% ethanol yield compared to the theoretical yield. Therefore, chemical pretreatment with phosphoric acid, a biological pretreatment with white-rot fungus Pleurotus floridanus, and their combination were carried out on OPEFB prior to the SSF. Pretreatment with phosphoric acid, combination of both methods and just fungal pretreatment improved the digestibility of OPEFB by 24.0, 16.5 and 4.5 times, respectively. During the SSF, phosphoric acid pretreatment, combination of fungal and phosphoric acid pretreatment and just fungal pretreatment resulted in the highest 89.4%, 62.8% and 27.9% of the theoretical ethanol yield, respectively. However, the recovery of the OPEFB after the fungal pretreatment was 98.7%, which was higher than after phosphoric acid pretreatment (36.5%) and combined pretreatment (45.2%).


Assuntos
Arecaceae/química , Biotecnologia/métodos , Etanol/metabolismo , Frutas/química , Ácidos Fosfóricos/farmacologia , Óleos de Plantas/química , Saccharomyces cerevisiae/metabolismo , Biomassa , Metabolismo dos Carboidratos/efeitos dos fármacos , Fermentação/efeitos dos fármacos , Óleo de Palmeira , Saccharomyces cerevisiae/efeitos dos fármacos
7.
J Dent ; 41(6): 535-42, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23578472

RESUMO

OBJECTIVES: To investigate grape seed extract proanthocyanidins' (PA) capability in improving dentin collagen's sustainability in an enzymatic environment, given that the size and shape of the collagen samples, and the manner to apply PA are both clinically relevant. METHODS: Human dentin was sectioned into 6-µm-thick films. After demineralisation in 35wt% phosphoric acid for 15s, the films were subject to 30s of treatment at PA concentrations of 0% (control), 0.5%, 1%, 2%, 3.75%, 7.5% and 15% (w/w), respectively. The films were then digested in 0.1wt% collagenase for 1h and 24h. The amount of degraded collagen in the liquid digests was determined by MALDI-TOF mass spectroscopy. The trend of PA's incorporation into dentin collagen was analysed by ATR-FTIR. RESULTS: The control exhibited complete digestion in 1h. In contrast, collagen treated with 0.5% and 1% PA afforded 13.84±4.69% and an undetectable level of degradation, respectively in the first 1h of digestion, and additional 17.48±4.38% and 4.50±1.68%, respectively in the following 23h. Collagen treated with ≥2wt% PA was not significantly digested regardless of digestion time. FTIR spectroscopy revealed that PA incorporation was saturated at ≥2wt% PA. CONCLUSION: Thirty seconds of PA treatment at 2wt% and above could provide optimal protection for dentin collagen against collagenase digestion. CLINICAL SIGNIFICANCE: This study demonstrated PA's extraordinary efficiency in stabilizing demineralised dentin collagen when it is applied in a clinical relevant manner, and identified the optimal conditions for its utilization.


Assuntos
Colágeno/efeitos dos fármacos , Dentina/efeitos dos fármacos , Extrato de Sementes de Uva/farmacologia , Inibidores de Metaloproteinases de Matriz/farmacologia , Proantocianidinas/farmacologia , Vitis , Sequência de Aminoácidos , Colágeno/análise , Colagenases/farmacologia , Humanos , Oligopeptídeos/análise , Ácidos Fosfóricos/farmacologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo , Desmineralização do Dente/fisiopatologia
8.
Molecules ; 17(12): 14995-5002, 2012 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-23247371

RESUMO

Oil palm empty fruit bunch (OPEFB) was pretreated using white-rot fungus Pleurotus floridanus, phosphoric acid or their combination, and the results were evaluated based on the biomass components, and its structural and morphological changes. The carbohydrate losses after fungal, phosphoric acid, and fungal followed by phosphoric acid pretreatments were 7.89%, 35.65%, and 33.77%, respectively. The pretreatments changed the hydrogen bonds of cellulose and linkages between lignin and carbohydrate, which is associated with crystallinity of cellulose of OPEFB. Lateral Order Index (LOI) of OPEFB with no pretreatment, with fungal, phosphoric acid, and fungal followed by phosphoric acid pretreatments were 2.77, 1.42, 0.67, and 0.60, respectively. Phosphoric acid pretreatment showed morphological changes of OPEFB, indicated by the damage of fibre structure into smaller particle size. The fungal-, phosphoric acid-, and fungal followed by phosphoric acid pretreatments have improved the digestibility of OPEFB's cellulose by 4, 6.3, and 7.4 folds, respectively.


Assuntos
Celulose/química , Frutas/química , Lignina/química , Óleos de Plantas/química , Arecaceae/química , Basidiomycota , Carboidratos/química , Fibras na Dieta , Ligação de Hidrogênio/efeitos dos fármacos , Hidrólise , Óleo de Palmeira , Ácidos Fosfóricos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
9.
J Food Sci ; 75(9): M574-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21535613

RESUMO

About 40000 people fall victim to Salmonella infections every year in the United States. Recent occurrences of Salmonella contaminated spinach and its recalls have accelerated the need for efficient antimicrobials targeting these pathogens. Our study was aimed at evaluating the inhibitory properties of malic, tartaric, and lactic acids, and grape seed extract (GSE) alone and in combinations and their application methods against Salmonella Typhimurium-inoculated spinach using a response surface method. Fresh spinach leaves were washed, disinfected with sodium hypochlorite solution (0.04% v/v), rewashed with sterile deionized (DI) water, and inoculated with a 2nd-day culture of S. Typhimurium (7.0 log CFU/mL). Adhered S. Typhimurium population on day 0 were 7.5 log CFU/g. These were treated with individual and combinations of organic acids with GSE or DI water (control) adjusted to the same pH as that of the test solutions with both the modes of application and leaves were refrigerated at 4 °C. Malic acid (2%) in combination with GSE (3%) or lactic acid (3%) sprayed electrostatically showed reductions of 2.6 to 3.3 log CFU/g compared to lower log reductions (0.0 to 0.3 log CFU/g) by day 14 if sprayed conventionally. These findings indicate that malic acid in combination with GSE/lactic acid solutions applied by electrostatic spraying exhibited higher inhibition of pathogens than conventional spraying and can be used for commercial applications to enhance food safety.


Assuntos
Descontaminação/métodos , Extrato de Sementes de Uva/farmacologia , Ácido Láctico/farmacologia , Malatos/farmacologia , Salmonella typhimurium/crescimento & desenvolvimento , Tartaratos/farmacologia , Adesinas Bacterianas/metabolismo , Anti-Infecciosos/farmacologia , Carga Bacteriana , Qualidade de Produtos para o Consumidor , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Manipulação de Alimentos , Conservação de Alimentos/métodos , Ácidos Fosfóricos/farmacologia , Salmonella typhimurium/patogenicidade , Hipoclorito de Sódio/farmacologia , Spinacia oleracea/microbiologia , Eletricidade Estática
10.
Orthod Fr ; 80(2): 179-92, 2009 Jun.
Artigo em Francês | MEDLINE | ID: mdl-19552877

RESUMO

Enamel conditioning (elimination of dental plaque and creation of an irregular surface) is an essential step before bonding of orthodontic brackets. The most popular procedure in our practice is bonding with resin which requires enamel etching in order to get enough shear bond strength. Many studies have tried to evaluate the effects of enamel bonding using the acid-etching procedure as well as the changes caused by detachment of brackets. Thanks to the development of other adhesives such as glass ionomer cements which chemically bind to the enamel, new enamel conditioning methods appeared, in particular sandblasting with aluminium oxide particles. This technique is a mechanical preparation of the tooth that avoids the harmful effects of acid products. By suitably choosing the parameters of sandblasting (pressure, time and quantity of powder), enamel loss is lower than with the acid-etch procedure and the surface of the enamel seems less affected. However the bond strength remains superior to the values required for treatment. The presented results indicate that enamel sandblasting can be considered as an alternative for the acid-etching technique currently used in orthodontic practice because it creates sufficient strength and respects enamel thickness better.


Assuntos
Colagem Dentária/métodos , Esmalte Dentário/ultraestrutura , Microabrasão do Esmalte/métodos , Aparelhos Ortodônticos , Preparo do Dente/métodos , Condicionamento Ácido do Dente/métodos , Resinas Acrílicas/farmacologia , Óxido de Alumínio/química , Esmalte Dentário/efeitos dos fármacos , Materiais Dentários/química , Humanos , Malatos/farmacologia , Microscopia Eletrônica de Varredura , Ácidos Fosfóricos/farmacologia , Estresse Mecânico , Propriedades de Superfície
11.
Bioorg Med Chem Lett ; 19(5): 1392-5, 2009 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-19181520
12.
J Oral Rehabil ; 36(5): 362-7, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19210680

RESUMO

This study was conducted to evaluate the effect of polyphosphoric acid (PPA) treatment on bone regeneration around titanium (Ti) implants in vivo. Adsorption of PPA by Ti was achieved by immersing Ti implants (2 mm in diameter, 4 mm in length) in different concentrations of PPA solution (0, 1 and 10 wt%) for 24 h at 37 degrees C after proper Ti surface cleaning. The treated Ti implants were implanted on 8-week-old-male rat (n = 30) tibiae. Two or four weeks after implantation, all animals were deeply anaesthetized and underwent perfusion fixation. Ten specimens in each condition were further immersed in the same fixative for 1 week and eventually embedded in polyester resin. Afterwards, undecalcified sections were ground to a thickness of approximately 70 microm parallel to the long axis of the implant. The sections were stained with basic fuchsine and methylene blue and then examined by light microscopy. For quantitative evaluation of bone regeneration around the implants, the bone-implant contact ratio (BICR) was determined. Polyphosphoric acid treatment of the Ti implant surface significantly enhanced direct bone contact to the Ti surface. Especially, the BICRs of the 1 wt% PPA-treated Ti implants were significantly higher than those of the control untreated Ti implants, both 2 and 4 weeks after implantation. At 4 weeks, 10 wt% PPA-treated implants also significantly increased the BICR as compared to that of the untreated Ti implants. These results suggest that PPA treatment promotes osteoconductivity of Ti in vivo.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Implantes Experimentais , Ácidos Fosfóricos/farmacologia , Polímeros/farmacologia , Titânio , Animais , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Masculino , Osseointegração/efeitos dos fármacos , Ratos , Ratos Wistar , Tíbia/anatomia & histologia , Tíbia/efeitos dos fármacos , Tíbia/cirurgia
13.
J Med Chem ; 51(8): 2412-20, 2008 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-18257544

RESUMO

A series of achiral hypoxia-activated prodrugs were synthesized on the basis of the DNA cross-linking toxin of the prodrug, ifosfamide. The hypoxia-selective cytotoxicity of several of the compounds was improved over previously reported racemic mixtures of chiral bioreductive phosphoramidate prodrugs. Prodrugs activated by 2-nitroimidazole reduction demonstrated up to 400-fold enhanced cytotoxicity toward H460 cells in culture under hypoxia versus their potency under aerobic conditions. Compounds were further assessed for their stability to cytochrome P450 metabolism using a liver microsome assay. The 2-nitroimidazole containing lead compound 3b (TH-302) was selectively potent under hypoxia and stable to liver microsomes. It was active in an in vivo MIA PaCa-2 pancreatic cancer orthotopic xenograft model as a monotherapy and demonstrated dramatic efficacy when used in combination with gemcitabine, extending survival with one of eight animals tumor free at day-44. Compound 3b has emerged as a promising antitumor agent that shows excellent in vivo efficacy and is currently being evaluated in the clinic.


Assuntos
Amidas/farmacologia , Antineoplásicos/farmacologia , Hipóxia Celular , Ácidos Fosfóricos/farmacologia , Amidas/química , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Camundongos , Microssomos Hepáticos/efeitos dos fármacos , Ácidos Fosfóricos/química , Solubilidade
14.
Commun Agric Appl Biol Sci ; 73(2): 343-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19226773

RESUMO

Erwinia spp. provokes soft rot on potato tubers during storage. No disinfection products are available on the market in the European Union to control these bacteria. We tested 3 products presented as good candidates to cure potato tubers from bacterial diseases. First, Anthium 500 (Du Pont de Nemours) a product based on chlorine dioxyde, then Phostrol (Nufarm) with phosphoric acid as a.i. and finally Solucuivre (Proval), a copper based product. We firstly managed disinfection trials: high Erwinia contaminated potato seed samples were treated by immersion and were then incubated, we observed the percentage of tubers rotting. Secondly, we managed protection trials: protected healthy tubers were incubated during 23 days in contact with rotting tubers. We evaluated weight loss after symptoms development. No tested product was effective to control Erwinia spp. on seed tubers in our trials conditions. Furthermore, we observed more rot development after Phostrol and Solucuivre application. We suppose that the product couldn't reach the latent bacteria and weakened the tubers. No protection effect was observed.


Assuntos
Desinfetantes/farmacologia , Erwinia/efeitos dos fármacos , Erwinia/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Solanum tuberosum/microbiologia , Compostos Clorados/efeitos adversos , Compostos Clorados/farmacologia , Contagem de Colônia Microbiana , Cobre/efeitos adversos , Cobre/farmacologia , Desinfetantes/efeitos adversos , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Óxidos/efeitos adversos , Óxidos/farmacologia , Ácidos Fosfóricos/efeitos adversos , Ácidos Fosfóricos/farmacologia , Solanum tuberosum/normas
15.
J Dent ; 35(5): 388-97, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17174020

RESUMO

OBJECTIVES: The purpose of this study was to evaluate the capacity of six contemporary self-etch primers/adhesives to demineralize ground enamel by means of ultrastructural analysis of the etching surface under SEM and by spectroscopic measurement of the percentage of calcium and phosphate ions dissolved. METHODS: Seventy non-carious extracted human third molars were sub-divided into 2 groups of 35 teeth each. The teeth of the first group were ground to expose flat, polished enamel surfaces 3-4mm thick. The samples thus obtained were treated with six self-etch bonding systems and a phosphoric acid gel (control group). The self-etch priming agent was then eliminated and the etched enamel surface observed by SEM. From the teeth of the second group, disc-shaped specimens were made from ground enamel and subjected to application of each of the six self-etchants. Once the etching product had been rinsed off, the rinse solution was analyzed by atomic flame spectroscopy to evaluate the percentage of calcium and phosphate ions dissolved. RESULTS: SEM images show that AdheSE, Adper Prompt L-Pop and Xeno III, despite having a less intensive etching efficacy than phosphoric acid, gave a regular pattern over a considerable surface area and depth. iBond and One-Up Bond F gave less regular demineralization. For Clearfil SE Bond, the demineralization was ineffective. Results of the percentage of mineral loss show that Adper Prompt L-Pop and Xeno III were the most efficient self-etch products. AdheSE, iBond and One-Up Bond F, respectively exhibited decreasing demineralizing capacity. Clearfil SE Bond, however, gave low proportions of calcium and phosphate ions loss and was considered unsatisfactory. CONCLUSION: The action on enamel was not the same for all self-etch systems tested. The etching potential of the self-etch adhesives was lower than that of phosphoric acid but some self-etch systems, particularly those with monomers containing phosphate derivatives, gave results close to those obtained with phosphoric acid.


Assuntos
Condicionamento Ácido do Dente , Esmalte Dentário/efeitos dos fármacos , Adesivos Dentinários/farmacologia , Cimentos de Resina/farmacologia , Cálcio/análise , Esmalte Dentário/ultraestrutura , Solubilidade do Esmalte Dentário , Humanos , Microscopia Eletrônica de Varredura , Dente Serotino , Ácidos Fosfóricos/farmacologia , Fósforo/análise
16.
Georgian Med News ; (135): 120-3, 2006 Jun.
Artigo em Russo | MEDLINE | ID: mdl-16905828

RESUMO

Considerable number of the investigations are dedicated to the study of the influences of the various agents on ionic homeostasis of the cell. However, there are actually no works related to the impact on these indices of homeopathic preparations (HP). In the present work influence of HP - stimulated phosphoric acid (PA), at low dilutions (10(-14) and 10(-42)) and non-stimulated PA, at high dilutions (10(-200) and 10(-400)), on transmembrane transport of Na+, K+, Ca2+, and enzymes - Na,K-ATPase and Ca-ATPase - was investigated. Experiments were carried out by means of ion-selective electrodes, in order to measure concentration of ions in the Ringer solution. Results have shown that HP at low dilution always stimulated observed indices, while HP at high dilution - suppressed these indices. Therefore, driving force of HP increases with dilution, because number of hydrate complexes increases and so does velocity of information transmission, which is responsible for different effects.


Assuntos
Cálcio/metabolismo , Homeopatia , Ácidos Fosfóricos/farmacologia , Potássio/metabolismo , Sódio/metabolismo , Animais , ATPases Transportadoras de Cálcio/análise , Embrião de Mamíferos/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Transporte de Íons/efeitos dos fármacos , Materia Medica/farmacologia , Camundongos , ATPase Trocadora de Sódio-Potássio/análise
17.
Curr Protoc Nucleic Acid Chem ; Chapter 13: Unit 13.1, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18428921

RESUMO

This overview summarizes methodology used for the synthesis of nucleoside mono-, di-, and triphosphates. Selected techniques such as the Mitsunobu reaction, displacement reactions involving nucleoside 5'-tosylates, "anion-exchange" techniques, and phosphoramidite and phosphoramidate methodologies are highlighted. The chemistry of phosphorylation is detailed with respect to advantages and limitations under various conditions. Applicability of the methods toward the synthesis of analogs such as imidophosphates, phosphorothioates, and radiolabeled nucleotides is also addressed.


Assuntos
Nucleosídeos/síntese química , Polifosfatos/síntese química , Amidas/química , Anidridos/química , Anidridos/farmacologia , Catálise , Modelos Biológicos , Nucleosídeos/química , Nucleosídeos/metabolismo , Nucleotídeos/química , Oligonucleotídeos/síntese química , Organofosfonatos/química , Fosfatos/síntese química , Fosfoadenosina Fosfossulfato/síntese química , Fosfoadenosina Fosfossulfato/química , Ácidos Fosfóricos/química , Ácidos Fosfóricos/farmacologia , Fósforo/química , Fosforilação
19.
Dent Mater J ; 22(3): 404-11, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14621005

RESUMO

The acid resistance of Nd:YAG laser-ablated enamel surfaces was studied by evaluating crystal structure, mineral distribution, and fluorescence radiance and image in the present study. For comparison, 37% phosphoric acid etching was performed. The formation of beta-tricalcium phosphate (beta-TCP) was confirmed in the laser-ablated surface. The Ca/P ratio increased after ablation due to mineral re-distribution. In contrast, the Ca/P ratio decreased after acid etching due to mineral loss. The laser-ablated enamels showed a smaller increase of fluorescence radiances and less clear laser confocal scanning microscope images than those observed in the acid-etched enamels. The former suggests a minimized mineral loss. The Nd:YAG laser irradiation will enhance the acid resistance and retard the carious progression in enamel.


Assuntos
Solubilidade do Esmalte Dentário/efeitos da radiação , Esmalte Dentário/efeitos da radiação , Lasers , Ácidos , Silicatos de Alumínio , Cálcio/análise , Fosfatos de Cálcio/efeitos da radiação , Cristalografia , Esmalte Dentário/efeitos dos fármacos , Solubilidade do Esmalte Dentário/efeitos dos fármacos , Microanálise por Sonda Eletrônica , Fluorescência , Humanos , Microscopia Confocal , Minerais/análise , Neodímio , Ácidos Fosfóricos/farmacologia , Fósforo/análise , Análise Espectral Raman , Desmineralização do Dente/metabolismo , Difração de Raios X , Ítrio
20.
Exp Mol Med ; 34(3): 211-23, 2002 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-12216113

RESUMO

Protein-tyrosine phosphatases (PTPs) constitute a family of receptor-like, and cytoplasmic enzymes, which catalyze the dephosphorylation of phosphotyrosine residues in a variety of receptors and signaling molecules. Together with protein tyrosine kinases (PTKs), PTPs are critically involved in regulating many cellular signaling processes. In this study, diverse compounds were screened for PTP inhibition and selectively screened for inhibitors with the end product inhibition properties. Among phosphate analogues and their derivatives for PTP inhibition, Keggin compounds phosphomolybdate (PM) and phosphotungstate (PT) strongly inhibited both PTP-1B and SHP-1, with K(i) values of 0.06-1.2 micromM in the presence of EDTA. Unlike the vanadium compounds, inhibition potencies of PM and PT were not significantly affected by EDTA. PM and PT were potent, competitive inhibitors for PTPs, but relatively poor inhibitors of Ser/Thr phosphatase. Interestingly, PM and PT did not inhibit alkaline phosphatase at all. The crystal structure of PTP-1B in complex with PM, at 2.0 A resolution, reveals that MoO(3), derived from PM by hydrolysis, binds at the active site. The molybdenium atom of the inhibitor is coordinated with six ligands: three oxo-ligands, two apical water molecules and a S atom of the catalytic cysteine residue. In support of the crystallographic finding, we observed that molybdenium oxides (MoO(3), MoO(2), and MoO(2)Cl(2)) inhibited PTP-1B with IC(50) in the range 5-15 micromM.


Assuntos
Inibidores Enzimáticos/farmacologia , Molibdênio/farmacologia , Ácidos Fosfóricos/farmacologia , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Proteínas Tirosina Fosfatases/química , Compostos de Tungstênio/farmacologia , Ligação Competitiva , Domínio Catalítico , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Ácido Edético/farmacologia , Humanos , Concentração Inibidora 50 , Cinética , Modelos Moleculares , Estrutura Terciária de Proteína , Proteínas Tirosina Fosfatases/isolamento & purificação , Especificidade por Substrato
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