Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Hum Mutat ; 20(1): 75, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12112662

RESUMO

Papillon Lefèvre syndrome (PLS) is an autosomal recessive disorder characterized by palmoplantar hyperkeratosis and severe periodontitis. The disease is caused by mutations in the cathepsin C gene (CTSC) that maps to chromosome 11q14. CTSC gene mutations associated with PLS have been correlated with significantly decreased enzyme activity. Mutational analysis of the CTSC gene in three North American families segregating PLS identified four mutations, including a novel mutation p.G139R. All mutations were associated with dramatically reduced CTSC protease enzyme activity. A homozygous c.96T>G transversion resulting in a p.Y32X change was present in a Mexican PLS proband, while one Caucasian PLS proband was a compound heterozygote for the p.Y32X and p.R272P (c.815G>C) mutations. The other Caucasian PLS proband was a compound heterozygote for c.415G>A transition and c.1141delC mutations that resulted in a p.G139R and a frameshift and premature termination (p.L381fsX393), respectively. The c.415G>A was not present in more than 300 controls, suggesting it is not a CTSC polymorphism. Biochemical analysis demonstrated almost no detectable CTSC activity in leukocytes of all three probands. These mutations altered restriction enzyme sites in the highly conserved CTSC gene. Sequence analysis of CTSC exon 3 confirmed the previously reported p.T153I polymorphism in 4 of the 5 ethnically diverse populations studied.


Assuntos
Catepsina C/genética , Doença de Papillon-Lefevre/genética , Sequência de Aminoácidos , Sequência de Bases , Catepsina C/metabolismo , DNA/química , DNA/genética , Análise Mutacional de DNA , Saúde da Família , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Dados de Sequência Molecular , Mutação , América do Norte , Doença de Papillon-Lefevre/enzimologia , Linhagem , Polimorfismo Genético , Homologia de Sequência de Aminoácidos
2.
J Periodontol ; 71(11): 1792-801, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11128930

RESUMO

Ultrasonic and sonic scalers appear to attain similar results as hand instruments for removing plaque, calculus, and endotoxin. Ultrasonic scalers used at medium power seem to produce less root surface damage than hand or sonic scalers. Due to instrument width, furcations may be more accessible using ultrasonic or sonic scalers than manual scalers. It is not clear whether root surface roughness is more or less pronounced following power-driven scalers or manual scalers. It is also unclear if root surface roughness affects long-term wound healing. Periodontal scaling and root planing includes thorough calculus removal, but complete cementum removal should not be a goal of periodontal therapy. Studies have established that endotoxin is weakly adsorbed to the root surface, and can be easily removed with light, overlapping strokes with an ultrasonic scaler. A significant disadvantage of power-driven scalers is the production of contaminated aerosols. Because ultrasonics and sonics produce aerosols, additional care is required to achieve and maintain good infection control when incorporating these instrumentation techniques into dental practice. Preliminary evidence suggests that the addition of certain antimicrobials to the lavage during ultrasonic instrumentation may be of minimal clinical benefit. However, more randomized controlled clinical trials need to be conducted over longer periods of time to better understand the long-term benefits of ultrasonic and sonic debridement.


Assuntos
Raspagem Dentária/instrumentação , Aerossóis , Microbiologia do Ar , Cálculos Dentários/terapia , Cemento Dentário/cirurgia , Equipamentos Odontológicos de Alta Rotação , Instrumentos Odontológicos , Placa Dentária/terapia , Segurança de Equipamentos , Humanos , Aplainamento Radicular/instrumentação , Sonicação/instrumentação , Terapia por Ultrassom/instrumentação
3.
J Am Dent Assoc ; 130(6): 801-7, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10377637

RESUMO

BACKGROUND: Although periodontal scaling and root planing, or SRP, is one of the most common procedures used in dental practice, there is little information available about the degree of postprocedural pain associated with it. The authors undertook this study to document the intensity and duration of pain after SRP with a view toward helping practitioners and their patients manage postprocedural discomfort. METHODS: Using the Heft-Parker self-assessment pain scale, 52 adults with moderate periodontitis evaluated their pain before and after SRP conducted with local anesthetic. RESULTS: After SRP, 28 percent of all patients reported faint-to-weak pain, 18 percent experienced weak-to-mild pain, 28 percent experienced mild-to-moderate pain, 8 percent had moderate-to-strong pain and 8 percent reported strong-to-intense pain. The average time to onset of maximum pain was approximately three hours after SRP, and the average duration of mild or greater pain was about six hours. Upon awakening the morning after SRP, subjects found that pain had returned to pre-SRP levels. Overall, 23 percent of all patients reported self-medicating with analgesics to relieve postprocedural pain. Women self-medicated earlier (P < .05) and more often than men (43 percent vs. 10 percent; P < .05). CONCLUSIONS: Patients experienced significant duration and magnitude of pain after SRP. This pain peaked between two and eight hours after SRP, lasted about six hours, and returned to pre-SRP levels by the morning after the procedure. Almost 25 percent of all patients self-medicated to relieve pain after SRP, and women took analgesic medication earlier and more often than men. CLINICAL IMPLICATIONS: Practitioners should consider using appropriate analgesic drugs to alleviate mild-to-moderate pain after SRP. On the basis of this study, it would appear that an analgesic that has a peak effect two to eight hours after the completion of SRP would be the most appropriate medication. Moreover, it is unlikely that analgesic medication would be needed by most patients beyond the day on which SRP was performed.


Assuntos
Raspagem Dentária/efeitos adversos , Dor Pós-Operatória/etiologia , Periodontite/terapia , Odontalgia/etiologia , Adolescente , Adulto , Idoso , Analgésicos/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Medição da Dor , Dor Pós-Operatória/tratamento farmacológico , Análise de Regressão , Aplainamento Radicular/efeitos adversos , Estatísticas não Paramétricas , Odontalgia/tratamento farmacológico
4.
J Clin Dent ; 8(2 Spec No): 54-61, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9238874

RESUMO

The intraoral antimicrobial activity of four commercial oral products-conventional NaF dentifrice (Crest), baking soda/peroxide/NaF dentifrice (Mentadent), essential oil mouthrinse (Listerine) and SnF2 dentifrice (Crest Plus Gum Care)-have been compared in three test regimens. Formulations were compared for their ability to suppress the regrowth and apical extension of dental plaque following toothbrushing during thirty hours of non-brushing where products were used as oral rinses (30-hour plaque regrowth model). Formulations were also compared for their ability to suppress the colony-forming units (cfu) of facultative anaerobic bacteria sampled from buccal gingival surfaces following use (Gingival Surface Microbial Index-GSMI model). Lastly, formulations were compared for effects in suppressing the glycolytic metabolic activity and regrowth activity of in vivo-treated dental plaques sampled at various periods following topical use and incubated under controlled ex vivo conditions (Plaque Glycolysis and Regrowth-PGRM model). In thirty-hour plaque regrowth testing, the rank ordered antimicrobial efficacy of formulations followed SnF2 > essential oils > NaF = water = baking soda/peroxide. In GSMI testing, all formulations were shown to suppress the cfu of facultative anaerobic bacteria relative to baseline, although SnF2 treatment was observed to reduce bacterial levels to a significantly greater degree than NaF dentifrice or baking soda/peroxide dentifrice up to two hours following brushing. In PGRM testing, the SnF2 dentifrice provided significant inhibition of bacterial metabolism and regrowth following topical application when compared with the NaF dentifrice as control. The baking soda/peroxide dentifrice provided no reduction in either bacterial metabolism or regrowth in PGRM. Previous studies had demonstrated modest effects for essential oil rinse in reducing PGRM plaque regrowth, with no effects for this treatment on plaque metabolism. Overall, these results demonstrate that SnF2 dentifrice provides substantial intraoral antimicrobial effects. The essential oil mouthrinse also exhibits significant intraoral antimicrobial effects, albeit apparently less than SnF2 dentifrice. The baking soda/peroxide dentifrice did not produce any antimicrobial effects following in vivo use compared with conventional dentifrice. These results provide mechanistic rationale for the chemotherapeutic efficacy of SnF2 and essential oil formulations in reducing gingivitis, while providing no support for the expectation of clinical efficacy for formulations containing baking soda and peroxide.


Assuntos
Bactérias Anaeróbias/efeitos dos fármacos , Placa Dentária/prevenção & controle , Dentifrícios/farmacologia , Antissépticos Bucais/farmacologia , Adulto , Análise de Variância , Contagem de Colônia Microbiana , Estudos Cross-Over , Placa Dentária/microbiologia , Índice de Placa Dentária , Dentifrícios/química , Dentifrícios/uso terapêutico , Combinação de Medicamentos , Feminino , Humanos , Peróxido de Hidrogênio/farmacologia , Masculino , Antissépticos Bucais/química , Antissépticos Bucais/uso terapêutico , Salicilatos/farmacologia , Bicarbonato de Sódio/farmacologia , Fluoreto de Sódio/farmacologia , Terpenos/farmacologia , Fluoretos de Estanho/farmacologia
5.
J Clin Periodontol ; 23(12): 1133-6, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8997659

RESUMO

Intracrevicular antimicrobial therapy is consistent with the site-specific nature of periodontitis. Considerable research has focused on the use of nonresorbable fibers. However, a bioerodible system is desirable. The purpose of this study was to assess tetracycline release and safety following a single application of a syringable 35% tetracycline hydrochloride in a lactic-glycolic acid gel. 31 generally healthy adult volunteers (mean age = 59 years) were enrolled in and completed this randomized, double-blind eight day study. 2, 6-10 mm non-adjacent interproximal pockets that bled on pocket probing were chosen as experimental sites in each subject. I experimental site and the surrounding gingival crevice received small particle size tetracycline in gel while the other site received larger particle size tetracycline in gel. Gingival crevicular fluid (GCF) was collected prior to treatment and 15 min, 1, 2, 3, 4 and 8 days post-treatment. GCF tetracyline concentrations were determined by agar diffusion bioassay and GCF volume measurements. 61% and 71% of sites had > or = 100 micrograms/ml tetracycline 3 days following application of large (mean concentration = 430 +/- 92 micrograms/ml) and small particle gels (mean concentration = 418 +/- 70 micrograms/ml), respectively. 37% and 55% of sites had measurable tetracycline 8 days after placement of large (mean concentration = 86 +/- 31 micrograms/ml) and small particle gels (mean concentration = 293 +/- 79 micrograms/ml), respectively. The most common adverse event was "bitter taste" (10% of subjects). Based upon the reduction in probing depths and % of sites bleeding on probing at 8 days relative to pretreatment, and the absence of any serious adverse events, it is concluded that these bioerodible gels are safe, and since the bacteriostatic range for most putative periodontopathogens is in the 2-10 micrograms/ml range, the tetracycline levels observed at days 3 and 8 likely represent significant antimicrobial efficacy.


Assuntos
Antibacterianos/administração & dosagem , Bolsa Periodontal/tratamento farmacológico , Tetraciclina/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Biodegradação Ambiental , Preparações de Ação Retardada , Método Duplo-Cego , Feminino , Géis , Líquido do Sulco Gengival , Glicolatos , Humanos , Ácido Láctico , Masculino , Pessoa de Meia-Idade , Tamanho da Partícula
6.
Curr Opin Periodontol ; 3: 78-84, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8624572

RESUMO

Caries and periodontal disease, the most widespread oral diseases, are commonly treated with various oral antiseptics. These antiseptics are derived from different chemical categories and have different mechanisms of action. Even though the properties of an ideal oral antiseptic have been identified, its formulation has proven elusive. Recent studies with chlorhexidine, triclosan, an amine and stannous fluoride rinse, and essential oil rinse, and others are discussed. Development of novel antiseptic products continues. The hope for the future is that now antiseptic products will treat oral disease better and oral health will improve.


Assuntos
Anti-Infecciosos Locais/uso terapêutico , Cárie Dentária/tratamento farmacológico , Antissépticos Bucais/uso terapêutico , Doenças Periodontais/tratamento farmacológico , Cetilpiridínio/uso terapêutico , Clorexidina/uso terapêutico , Placa Dentária/prevenção & controle , Humanos , Maleatos/uso terapêutico , Polietilenos/uso terapêutico , Fluoretos de Estanho/uso terapêutico , Triclosan/uso terapêutico
8.
Am J Dent ; 5(3): 143-6, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1388952

RESUMO

The purpose of this study was to evaluate the effectiveness of an antimicrobial rinse (chlorhexidine) compared to a positive control of mechanical oral hygiene in reducing interdental gingival inflammation. The mechanical group showed a significantly greater reduction in interdental gingivitis as determined by bleeding compared to the chemical rinse. Even though the chemical rinse has been shown to be effective in reducing inflammation on the visible buccal and lingual gingival surfaces, it is significantly less effective than the mechanical device in reducing bleeding in the interdental area.


Assuntos
Clorexidina/análogos & derivados , Dispositivos para o Cuidado Bucal Domiciliar , Gengivite/terapia , Antissépticos Bucais/uso terapêutico , Higiene Bucal/instrumentação , Adulto , Clorexidina/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice Periodontal
9.
Artigo em Inglês | MEDLINE | ID: mdl-1428607

RESUMO

The potential for guided tissue regeneration was evaluated in one-walled interproximal sites in Macaca fascicularis. Histologic differences were evaluated at 1 and 3 months. Within the experimental (barrier) group, 100% of the root surfaces with potential for regeneration were covered with new cementum, whereas the control specimens had 20% or less new cementum. The amount of regeneration was determined by the position of the barrier membrane; the more coronal the barrier, the greater the regeneration. Observations indicated that the optimal time for barrier removal is between 1 and 3 months.


Assuntos
Regeneração Tecidual Guiada Periodontal , Doenças Periodontais/cirurgia , Animais , Inserção Epitelial/fisiopatologia , Macaca fascicularis , Masculino , Membranas Artificiais , Ligamento Periodontal/fisiopatologia , Politetrafluoretileno , Cicatrização
10.
J Clin Periodontol ; 17(10): 709-13, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2262584

RESUMO

Cementum thickness increases uniformly with age, and questionably from functional stimulation due to tensional forces. Mesial drift of teeth results in tensional forces on distal root surfaces. This study evaluated whether there was any discernible effect on cementum thickness related to mesial drift in humans. The material consisted of maxillary and mandibular bicuspids and molars with their surrounding periodontia from 5 humans (mean age at death, 48.6 years). The teeth and tissues had been sectioned histologically in a mesio-distal plane, and the analysis for each tooth was done using 3 step-serial sections from the mid-buccolingual region. On the mesial and distal surface of each tooth, cementum thickness was measured in microns at 3 defined locations at a level representing the mid-point of root length for bicuspids and molars. Means from the measurements on mesial and distal surfaces were compared using descriptive and and inferential statistical methods. For each individual tooth analyzed, the cementum was thicker on the distal surface (range greater, 32-107%; mean, 69%). The statistical comparisons showed that cementum thickness on the distal surface was significantly greater for bicuspids (mesial, 135 microns: distal, 216 microns), molars (mesial, 154 microns: distal, 284 microns), and all teeth combined (mesial, 154 microns: distal, 284 microns). The magnitude of this difference became greater with increasing age. It was concluded that cementum thickness was markedly greater on the distal surfaces of teeth from adult humans, and that this may be due to functional stimulation from mesial drift over time.


Assuntos
Cemento Dentário/patologia , Movimento Mesial dos Dentes/fisiopatologia , Adulto , Envelhecimento/fisiologia , Esmalte Dentário/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Odontometria , Ligamento Periodontal/patologia , Periodontite/patologia , Raiz Dentária/patologia
11.
J Am Dent Assoc ; 118(4): 463-5, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2785128

RESUMO

This study screened 1986 ADA annual session participants for interdental gingival inflammation by using the Eastman Interdental Bleeding Index (EIBI). The EIBI provides a sensitive and objective measure of interdental gingival inflammation, and has been shown to be reliable. At least one bleeding site was found in 81% of the 435 dentists examined. This study showed that in a dental population, the prevalence of gingival inflammation was high when the health of interdental tissues was assessed.


Assuntos
Gengivite/epidemiologia , American Dental Association , Estudos Transversais , Hemorragia Gengival/diagnóstico , Hemorragia Gengival/epidemiologia , Gengivite/diagnóstico , Humanos , Índice Periodontal , Estados Unidos
12.
Comput Biomed Res ; 22(1): 1-10, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2914420

RESUMO

Dental research studies often produce relatively small data sets in which observations are serially or spatially correlated. Rerandomization tests are presented as alternatives to analysis of variance and multivariate analysis for assessing group differences using such data. Rerandomization tests are particularly useful when the investigator is unwilling to make strong assumptions about the nature of the serial correlation or the distribution of the data. Two examples are discussed that demonstrate these techniques.


Assuntos
Interpretação Estatística de Dados , Odontologia , Distribuição Aleatória/métodos , Projetos de Pesquisa/métodos , Fluoretos/farmacocinética , Gengiva/citologia , Saliva/metabolismo
13.
J Periodontol ; 60(2): 84-90, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2786069

RESUMO

The aim of this study was to determine the effects of personal oral hygiene and subgingival scaling on bleeding interdental gingiva. The Eastman Interdental Bleeding Index (EIBI) was used to clinically evaluate interdental gingival status. Forty-seven bleeding interdental sites in 47 patients were divided into three groups. Sites in Group I bled on stimulation with wooden interdental cleaners. Groups II and III initially bled but were converted to nonbleeding with oral hygiene alone or oral hygiene combined with subgingival scaling, respectively. Interdental gingival biopsies were obtained and subjected to morphometric analysis to compare the three groups. The findings from this study indicated that: (A) personal oral hygiene reduced the magnitude and extent of the interdental inflammatory lesion; (B) subgingival scaling plus oral hygiene decreased the interdental inflammatory lesion to a greater extent than oral hygiene alone; (C) significant repair of the interdental lesion occurred within four weeks; and (D) the EIBI was an effective method for monitoring the effects of therapy directed towards resolution of the interdental inflammatory lesion.


Assuntos
Hemorragia Gengival/prevenção & controle , Gengivite/prevenção & controle , Hemorragia Bucal/prevenção & controle , Higiene Bucal , Curetagem Subgengival , Adulto , Idoso , Colágeno , Tecido Conjuntivo/patologia , Dispositivos para o Cuidado Bucal Domiciliar , Epitélio/patologia , Feminino , Gengiva/patologia , Gengivite/patologia , Humanos , Masculino , Pessoa de Meia-Idade
14.
J Periodontol ; 59(11): 722-7, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3060580

RESUMO

Interdental gingival tissues are designated inflamed on the basis of their color and bleeding after stimulation. Gingival bleeding was previously shown in histological studies to indicate the presence of inflammatory lesions. The present study was undertaken to determine associations between bleeding and visual signs of interdental gingival inflammation. Each interdental site in 82 males, aged 18 to 30, was evaluated for the presence or absence of visual signs of inflammation. The interdental sites on one side of the mouth were evaluated for bleeding tendency using the Papilla Bleeding Index (PBI), while the other half was evaluated using the Eastman Interdental Bleeding Index (EIBI). The percentage of inflamed areas detected with the EIBI and visual method was similar and significantly higher than with the PBI. When the visually noninflamed sites were examined, 38.5% of these areas bled, indicating that interdental inflammatory lesions existed in the absence of visual signs of inflammation. Of the sites that bled but were visually noninflamed, 33.1% were detected using the PBI, while 66.9% were detected using the EIBI. The Eastman Interdental Bleeding Index was a more reliable clinical indicator for detecting interdental inflammatory lesions than the Papilla Bleeding Index.


Assuntos
Hemorragia Gengival/patologia , Gengivite/patologia , Hemorragia Bucal/patologia , Índice Periodontal , Adolescente , Adulto , Hemorragia Gengival/fisiopatologia , Gengivite/fisiopatologia , Humanos , Masculino , Sensibilidade e Especificidade
16.
J Periodontol ; 59(2): 80-6, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3258031

RESUMO

A previous study demonstrated that the combination of subgingival scaling and improved oral hygiene resulted in a reduction of clinical and histological signs of interdental gingival inflammation, changes that were associated with a cessation of interdental gingival bleeding. The present study compared, histologically, the interdental tissues of bleeding sites with sites that initially bled but had been converted to nonbleeding by an oral hygiene program alone. Morphometric analysis of interdental gingiva demonstrated that conversion from bleeding to nonbleeding was associated with a significant reduction in the inflamed connective tissue component. This study showed that an oral hygiene program consisting of toothbrushing and interdental cleaning could significantly reduce interdental inflammation, and that bleeding determinations monitored the effects of this therapy.


Assuntos
Placa Dentária/prevenção & controle , Hemorragia Gengival/patologia , Hemorragia Bucal/patologia , Higiene Bucal , Adulto , Idoso , Dispositivos para o Cuidado Bucal Domiciliar , Feminino , Gengiva/patologia , Hemorragia Gengival/terapia , Gengivite/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Escovação Dentária
17.
Biomed Mass Spectrom ; 7(6): 247-56, 1980 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7426688

RESUMO

Cannabis sativa L. contains more than 420 different constituents. Sixty-one of these constituents are cannabinoids. The electron voltage selected ion monitoring technique was used in the study of this unique group on natural compounds. Mass spectra of each compound were recorded at various eV settings (5.5-21 eV). The electron voltage selected ion recordings were obtained by plotting the relative intensities of characteristic fragment ions against electron voltage. The method was proven useful in the structure analysis of cannabinoids since it requires only minute quantities of sample. It was possible to recognize homologs and to differentiate positional and double bond isomers as well as cannabinoids with the same molecular weight.


Assuntos
Canabinoides/análise , Cannabis/análise , Cromatografia Gasosa/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Isomerismo , Peso Molecular
18.
J Pharm Sci ; 68(1): 45-8, 1979 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-758464

RESUMO

Binding of the antimalarial alpha-dibutylaminomethyl-2,6-bis(trifluoromethylphenyl)-4-pyridinemethanol with human serum albumin was studied using difference spectroscopy, fluorescence quenching, and equilibrium dialysis. Results indicated that the number of high affinity binding sites of the drug on protein is 0.45, with the total number of binding sites being 3.3--4.0. The binding constants were in the range of 0.57--4.00 x 10(6) M-1. The drug was bound more strongly to a nonionic detergent than to either a cationic or anionic detergent. Interpretation of these data and fluorescence quenching results indicated that the drug is possibly bound to a hydrophobic site on human serum albumin.


Assuntos
Antimaláricos/sangue , Picolinas/sangue , Albumina Sérica/metabolismo , Sítios de Ligação , Diálise , Humanos , Técnicas In Vitro , Ligação Proteica , Espectrometria de Fluorescência , Espectrofotometria , Tensoativos
19.
Res Commun Chem Pathol Pharmacol ; 22(2): 329-43, 1978 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-734218

RESUMO

Studies were carried out with deuterated methionine (methyl-d--3) to determine if methylthio metabolites of naphthalene were formed in vivo by reaction with methionine-derived metabolites. Rats were maintained on a methionine-free diet for nine days followed by eight days on the same diet supplemented with L-methionine-d--3 prior to administration of naphthalene. When naphthalene metabolites isolated from urine were characterized by GC and GC-MS procedures, it was found that the incorporation of deuterium into the methylthio metabolites, as well as into a catechol methyl ether, was approximately 40%. These results show that the methyl group was derived from methionine.


Assuntos
Metionina/metabolismo , Naftalenos/metabolismo , Animais , Cromatografia Gasosa , Dieta , Masculino , Espectrometria de Massas , Metionina/deficiência , Conformação Molecular , Neomicina/farmacologia , Ratos
20.
J Pharm Sci ; 67(9): 1224-8, 1978 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29114

RESUMO

Variations of the absorption and fluorescence spectra of the experimental antimalarial drug, alpha-dibutylaminomethyl-2,6-bis(p-trifluoromethylphenyl)-4-pyridinemethanol, were investigated throughout the pH region in concentrated sulfuric acid media and in n-hexane. The predominant prototropic species at physiological pH is the singly charged cation. In the pH 6--12 region, the structured fluorescence of the monocation is quenched with the concomitant appearance of a diffuse, long wavelength emission while the corresponding absorption spectra shift only slightly to longer wavelengths. Furthermore, the dibutylamino group exhibits an unusually low basicity. This behavior is explained as due to the formation of an intramolecular hydrogen bond in the neutral molecule in the ground and lowest excited singlet states. A similar intramolecular hydrogen bond in the monocation is not spectroscopically visible.


Assuntos
Antimaláricos , Picolinas , Antimaláricos/análise , Fenômenos Químicos , Química , Concentração de Íons de Hidrogênio , Picolinas/análise , Solventes , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...