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1.
Int Endod J ; 47(7): 704-10, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24175874

RESUMO

AIM: To investigate the levels of nine metals [aluminium (Al), antimony (Sb), arsenic (As), beryllium (Be), cadmium (Cd), chromium (Cr), iron (Fe), lead (Pb) and molybdenum (Mo)] in MTA Angelus, Micro Mega MTA and Bioaggregate using inductively coupled plasma-optical emission spectrometry (ICP-OES). METHODOLOGY: Each material (0.2 g) was digested using a mixture of hydrochloric and nitric acids and then filtered. The levels of nine metals in the resulting filtrates were measured by ICP-OES. The results were statistically analysed using one-way anova and the Bonferroni test. RESULTS: MTA Angelus contained more aluminium, beryllium and chromium than Micro Mega MTA (P < 0.05), whilst their levels of arsenic, cadmium and iron were similar. Antimony, lead and molybdenum were not detected in any of the three tested cements. Bioaggregate contained trace amounts of aluminium. CONCLUSIONS: MTA Angelus and Micro Mega MTA contained small amounts of seven tested metal oxides. Bioaggregate only contained trace amounts of aluminium.


Assuntos
Compostos de Cálcio/química , Metais/análise , Silicatos/química , Oligoelementos/análise , Calibragem , Análise Espectral/métodos
2.
J Visc Surg ; 160(1): 12-18, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35459632

RESUMO

INTRODUCTION: The standard of care for intraperitoneal injury in hemodynamically stable patients after blunt abdominal trauma has been replaced by non-operative management (NOM). However, selective NOM, depending on the situation, seems necessary in determining the treatment plan. In this study, we attempted to identify risk factors for surgical or angiographic intervention (SAI) in hemodynamically stable blunt abdominal trauma patients. METHODS: This retrospective study which included adult patients who were brought to a regional trauma center was conducted from March 2015 to October 2019. We evaluated the characteristics of blunt abdominal trauma patients and analyzed factors that were related to the requirement of SAI in these patients. Patients were divided into SAI and conservative management (CM) groups. RESULTS: We reviewed 1,176 patients, and after exclusions, of whom 248 blunt abdominal trauma and free fluid observed on CT were identified. The mean pulse rate was higher in the SAI than in the CM (P=0.025). Laboratory findings showed that lactate and delta neutrophil index (DNI) levels were higher in the SAI than in the CM (P=0.002 and 0.026 respectively). Additionally, the mean free fluid size in the SAI (85.69mm) was significantly larger than that in the CM (68.12mm; P=0.001), and blush was more frequently observed in the SAI (P<0.001). In multivariate analysis, only blush was an independent prognostic factor for SAI (OR 11.7, 95% CI, 5.1-30.8, P<0.001). CONCLUSION: In hemodynamically stable patients with blunt abdominal trauma, blush but also high lactate and DNI are associated with the requirement of interventional radiology and/or surgery.


Assuntos
Traumatismos Abdominais , Ferimentos não Penetrantes , Adulto , Humanos , Traumatismos Abdominais/diagnóstico por imagem , Traumatismos Abdominais/cirurgia , Estudos Retrospectivos , Fatores de Risco , Centros de Traumatologia , Ferimentos não Penetrantes/diagnóstico por imagem , Ferimentos não Penetrantes/cirurgia
3.
Br J Cancer ; 104(4): 605-12, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21326246

RESUMO

BACKGROUND: Advanced biliary cancer is often treated with fluoropyrimidine-based chemotherapy. In this study, we evaluated the efficacy and tolerability of a combination of S-1, an oral fluoropyrimidine prodrug, and oxaliplatin in patients with metastatic biliary cancer. METHODS: Patients with histologically confirmed metastatic biliary cancer and no history of radiotherapy or chemotherapy were enrolled. Oxaliplatin was administered intravenously (130 mg m(-2)), followed by 14-day administration of oral S-1 (40 mg m(-2) twice daily) with a subsequent 7-day rest period every 21 days. Pharmacokinetic analysis of S-1 was performed at cycle 1. Patients were genotyped for CYP2A6 polymorphisms ((*)1, (*)4, (*)7, (*)9 or (*)10), and pharmacokinetic and clinical parameters compared according to the CYP2A6 genotype. RESULTS: In total, 49 patients were evaluated, who received a median of four cycles. The overall response rate was 24.5%. Median progression-free and overall survival was 3.7 and 8.7 months, respectively. The most common haematological grade 3 out of 4 toxicity was neutropenia (14%), while non-hematological grade 3 out of 4 toxicities included anorexia (14%), nausea (12%), asthenia (10%), vomiting (10%), and diarrhoea (4%). Biotransformation of S-1 (AUC(0-24 h) of 5-fluorouracil/AUC(0-24 h) of tegafur) was 1.85-fold higher for the *1/*1 group than for the other groups (90% confidence interval 1.37-2.49). Diarrhoea (P=0.0740), neutropenia (P=0.396), and clinical efficacy (response rate, P=0.583; PFS, P=0.916) were not significantly associated with CYP2A6 genotype, despite differences in 5-FU exposure. CONCLUSION: The combination of S-1 and oxaliplatin appears to be active and well tolerated in patients with metastatic biliary cancer, and thus is feasible as a therapeutic modality. CYP2A6 genotypes are associated with differences in the biotransformation of S-1. However, the impact of the CYP2A6 polymorphism on variations in clinical efficacy or toxicity requires further evaluation.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Hidrocarboneto de Aril Hidroxilases/genética , Neoplasias do Sistema Biliar/tratamento farmacológico , Neoplasias do Sistema Biliar/genética , Compostos Organoplatínicos/administração & dosagem , Ácido Oxônico/administração & dosagem , Tegafur/administração & dosagem , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Neoplasias do Sistema Biliar/metabolismo , Neoplasias do Sistema Biliar/patologia , Biomarcadores Farmacológicos/análise , Biomarcadores Farmacológicos/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/fisiologia , Citocromo P-450 CYP2A6 , Combinação de Medicamentos , Feminino , Humanos , Inativação Metabólica/genética , Inativação Metabólica/fisiologia , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/efeitos adversos , Compostos Organoplatínicos/farmacocinética , Oxaliplatina , Ácido Oxônico/efeitos adversos , Ácido Oxônico/farmacocinética , Polimorfismo de Nucleotídeo Único/fisiologia , Tegafur/efeitos adversos , Tegafur/farmacocinética , Resultado do Tratamento , Adulto Jovem
4.
Clin Pharmacol Ther ; 70(3): 228-36, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11557910

RESUMO

OBJECTIVE: Our objective was to investigate ethnic differences in the oral pharmacokinetics of nifedipine and erythromycin, both typical cytochrome P4503A (CYP3A) substrates, in Koreans and Caucasians and to identify the nature of any correlations between the pharmacokinetic parameters of the two drugs. METHODS: Twenty healthy male volunteers (10 Koreans and 10 Caucasians) received single oral doses of nifedipine (10 mg) or erythromycin (500 mg) in a randomized 2-way crossover study. Pharmacokinetic evaluations were performed, and parameters were compared for the two ethnic groups. During the nifedipine study period, hemodynamic measurements were conducted to determine the pharmacodynamic relevance of the pharmacokinetic differences. RESULTS: Koreans showed area under the concentration-time curves (AUCs) for both drugs that were 1.6 to 1.7 times higher than those of Caucasians. This difference decreased to 1.3 when normalized for body weight. Significant correlation between the AUCs of the two drugs was not evident. Hemodynamic changes after nifedipine administration paralleled those of the pharmacokinetic differences, with significantly greater decreases in blood pressure and total peripheral resistance noted in Koreans. CONCLUSIONS: Koreans showed significantly lower oral clearances of nifedipine and erythromycin, probably because of genetic differences attributed to the CYP3A enzymes.


Assuntos
Antibacterianos/farmacocinética , Bloqueadores dos Canais de Cálcio/farmacocinética , Eritromicina/farmacocinética , Nifedipino/farmacocinética , Adulto , Área Sob a Curva , Povo Asiático , Peso Corporal/fisiologia , Estudos Cross-Over , Método Duplo-Cego , Humanos , Absorção Intestinal , Masculino , Comprimidos com Revestimento Entérico , População Branca
5.
Clin Pharmacol Ther ; 69(4): 266-73, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11309556

RESUMO

BACKGROUND: Moclobemide, an antidepressant with selective monoamine oxidase-A inhibitory action, is known to be metabolized by CYP2C19 and is also reported to be an inhibitor of CYP2C19, CYP2D6, and CYP1A2. To confirm the involvement of CYP2C19, we performed a pharmacokinetic interaction study. METHODS: The effect of omeprazole on the pharmacokinetics of moclobemide was studied in 16 healthy volunteers. The volunteer group comprised 8 extensive metabolizers and 8 poor metabolizers of CYP2C19, which was confirmed by genotyping. Subjects were randomly allocated into two sequence groups, and a single-blind, placebo-controlled, two-period crossover study was performed. In study I, a placebo was orally administered for 7 days. On the eighth morning, 300 mg of moclobemide and 40 mg of placebo were coadministered with 200 mL of water, and a pharmacokinetic study was performed. During study II, 40 mg of omeprazole was given each morning instead of placebo, and pharmacokinetic studies were performed on the first and eighth day with 300 mg of moclobemide coadministration. RESULTS: The inhibition of moclobemide metabolism was significant in extensive metabolizers even after a single dose of omeprazole. After daily administration of omeprazole for 1 week, the pharmacokinetic parameters of moclobemide and its metabolites in extensive metabolizers changed to values similar to those in poor metabolizers. In poor metabolizers, no remarkable changes in the pharmacokinetic parameters were observed. CONCLUSION: Our results show that CYP2C19 is an important enzyme in the elimination of moclobemide and that it is extensively inhibited by omeprazole in extensive metabolizers, but not in poor metabolizers.


Assuntos
Antidepressivos/farmacocinética , Hidrocarboneto de Aril Hidroxilases , Sistema Enzimático do Citocromo P-450/genética , Inibidores Enzimáticos/farmacologia , Oxigenases de Função Mista/genética , Moclobemida/farmacocinética , Omeprazol/farmacologia , Polimorfismo Genético , Adulto , Área Sob a Curva , Benzamidas/farmacocinética , Estudos Cross-Over , Citocromo P-450 CYP2C19 , Inibidores das Enzimas do Citocromo P-450 , Sistema Enzimático do Citocromo P-450/fisiologia , Interações Medicamentosas , Genótipo , Humanos , Oxigenases de Função Mista/antagonistas & inibidores , Oxigenases de Função Mista/fisiologia , Morfolinas/farmacocinética , Distribuição Aleatória
6.
Insect Biochem Mol Biol ; 28(3): 163-71, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9654739

RESUMO

cDNAs encoding chitinases were cloned and characterized from Bombyx mori and Hyphantria cunea, and their gene expression during the metamorphosis was also studied. The chitinase cDNA from B. mori encodes a protein of 565 amino acids with a calculated molecular mass of 63.4 kDa and the H. cunea chitinase cDNA encodes a protein of 553 amino acids with a calculated molecular mass of 62.0 kDa. Amino acid alignment of the two chitinases revealed 75% homology and 77-80% with M. sexta chitinase. The putative cleavage site of the signal peptide was between amino acid residues 20 and 21 for both chitinases. There were three potential N-glycosylation sites in the chitinase of B. mori at the amino acid residues 86-89, NFTS 304-307, NATG, 398-401, NYTV, whereas two potential N-glycosylation sites were present at the amino acid residues 86-89, NFTA and 304-307, NATG, in that of H. cunea. Southern blot analysis of total genomic DNA suggested that the B. mori genome has only one chitinase gene detectable by the cDNA probe and the H. cunea genome has one or two chitinase gene copies. Northern analysis indicated that gene expression was up-regulated during the molting process, larval-pupal transformation and pupal-adult transformation, when enzymatic degradation of cuticle was occurring.


Assuntos
Bombyx/enzimologia , Bombyx/genética , Quitinases/genética , DNA Complementar/genética , Mariposas/enzimologia , Mariposas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação , Bombyx/crescimento & desenvolvimento , Quitinases/química , Quitinases/metabolismo , Clonagem Molecular , Primers do DNA/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Genes de Insetos , Glicosilação , Manduca/enzimologia , Manduca/genética , Metamorfose Biológica/genética , Metamorfose Biológica/fisiologia , Dados de Sequência Molecular , Peso Molecular , Mariposas/crescimento & desenvolvimento , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Homologia de Sequência de Aminoácidos
7.
J Biochem ; 128(6): 1059-72, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11098150

RESUMO

Saccharomyces cerevisiae has three distinct citrate synthases, two located in mitochondria (mature Cit1p and Cit3p) and one in peroxisomes (mature Cit2p). While the precursor of the major mitochondrial enzyme, Cit1p, has a signal for mitochondrial targeting at its N-terminus (MTS), Cit2p has one for peroxisomal targeting (PTS1) at its C-terminus. We have previously shown that the N-terminal segment of Cit2p is removed during import into peroxisomes [Lee, H.S. et al. (1994) Kor. J. Microbiol. 32, 558-564], which implied the presence of an additional N-terminal sorting signal. To analyze the function of the N-terminal region of Cit2p in protein trafficking, we constructed the N-terminal domain-swapped versions of Cit1p and Cit2p. Both fusions, Cit1::Cit2 and Cit2::Cit1, complemented the glutamate auxotrophy caused by the double-disruption of the CIT1 and CIT2 genes. In addition, part of the Cit2::Cit1 fusion protein, as well as Cit1::Cit2, was shown to be transported into both mitochondria and peroxisomes. The subcellular localization of the recombinant fusion proteins containing various N-terminal segments of Cit2p fused to a mutant version of green fluorescent protein (GFP2) was also examined. As a result, we found that the 20-amino acid N-terminal segment of Cit2p contains a cryptic cleavable targeting signal for both peroxisomes and mitochondria. In addition, we show that the peroxisomal import process mediated by the N-terminal segment of Cit2p was not affected by the disruption of either PEX5 (encoding PTS1 receptor) or PEX7 (encoding PTS2 receptor).


Assuntos
Citrato (si)-Sintase/metabolismo , Peroxissomos/enzimologia , Sinais Direcionadores de Proteínas , Saccharomyces cerevisiae/enzimologia , Sequência de Aminoácidos , Sequência de Bases , Citrato (si)-Sintase/química , Citrato (si)-Sintase/genética , Primers do DNA , DNA Fúngico , Proteínas de Fluorescência Verde , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Microscopia Confocal , Mitocôndrias/enzimologia , Dados de Sequência Molecular , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Homologia de Sequência do Ácido Nucleico
8.
J Clin Pharmacol ; 40(7): 752-61, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10883417

RESUMO

To evaluate the pharmacokinetic/pharmacodynamic characteristics of SKP-450, a novel K+ channel opener, a single blind, randomized, placebo-controlled, dose-rising, parallel-group study was conducted in 28 healthy volunteers. The volunteers were randomly allocated to dosage groups of 50 micrograms, 100 micrograms, 200 micrograms, and 300 micrograms. Single doses of SKP-450 were administered orally, after overnight fasting, and serial blood sampling and pharmacodynamic measurements were performed up to 48 hours after the drug was administered. The 200 micrograms group was further studied for food interactions in a crossover fashion. Drug concentrations in plasma were determined by HPLC. Hemodynamic changes after drug administration were evaluated by serial measurements of blood pressure (BP), pulse rate (PR), cardiac index (CI), and total peripheral resistance (TPR), using computerized impedance cardiography. Changes in plasma renin activity (PRA) and aldosterone concentrations (PAC) were determined 4 and 24 hours after drug administration. Both SKP-450 and SKP-818, an active metabolite, showed linear pharmacokinetic characteristics, and food intake did not significantly affect the pharmacokinetic characteristics of either compound. Dose-related pharmacological effects were obvious for both the 200 micrograms and 300 micrograms groups. Hemodynamic parameters related to vasodilation and reflex tachycardia, such as maximum changes in diastolic BP, PR, CI, and TPR, showed significant dose-dependent changes. The area under the time-effect curve (AUEC) of the parameters also showed a similar dose-dependent pattern. The PRA and PAC exhibited significant changes 4 hours after drug administration in the 300 micrograms group. Adverse effects, such as headaches, were more frequently observed at the higher dose levels. SKP-450 was generally well tolerated by these normotensive subjects. The antihypertensive efficacy of SKP-450 needs to be evaluated in hypertensive patients after multiple dosing.


Assuntos
Canais de Potássio/metabolismo , Administração Oral , Adulto , Benzopiranos/efeitos adversos , Benzopiranos/farmacocinética , Benzopiranos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Cefaleia/etiologia , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pirrolidinonas/efeitos adversos , Pirrolidinonas/farmacocinética , Pirrolidinonas/farmacologia , Método Simples-Cego , Vasodilatadores/efeitos adversos , Vasodilatadores/farmacocinética , Vasodilatadores/farmacologia
9.
FEMS Microbiol Lett ; 145(1): 71-6, 1996 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-8931329

RESUMO

DNA fragments homologous to chitin synthase were amplified from the genomic DNA of Penicillium chrysogenum by PCR. Cloning and sequencing of the PCR-amplified fragments led to the identification of four different genes, designated PcCHS1, PcCHS2, PcCHS3, and PcCHS4. By comparison of the deduced amino acid sequences, PcCHS1 was identified as a gene for class I chitin synthase, PcCHS2 and PcCHS3 were for class II, and PcCHS4 was for class III. Among these only PcCHS4 includes an intervening sequence of 56 bp. The analysis of the deduced amino acid sequences revealed a close evolutionary relationship between Penicillium and ascomycetous fungi.


Assuntos
Quitina Sintase/genética , Penicillium chrysogenum/enzimologia , Penicillium chrysogenum/genética , Sequência de Aminoácidos , Sequência de Bases , Southern Blotting , Clonagem Molecular , Genes Bacterianos/genética , Genoma , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
10.
FEMS Microbiol Lett ; 159(1): 77-84, 1998 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9485597

RESUMO

Degenerated PCR primers were used to amplify chitin synthase genes from genomic DNA of Metarhizium anisopliae var. anisopliae. Through cloning and sequencing of approximately 600-bp fragments amplified by PCR, we found three genes encoding different types of chitin synthases, designated MaCHS1, MaCHS2, and MaCHS3. Southern blot analysis performed on genomic DNA showed that each of the chitin synthases MaCHS1, MaCHS2, and MaCHS3 is encoded by a single copy gene. Alignment of their deduced amino acid sequences with those of other euascomycetes separated the sequences into three distinct classes. MaCHS1 was identified as a gene for class I chitin synthase, MaCHS2 for class II, and MaCHS3 for class III. The UPGMA dendrogram and phylogenetic tree of the deduced amino acid sequences revealed the taxonomic and evolutionary position of Metarhizium anisopliae var. anisopliae.


Assuntos
Quitina Sintase/genética , Insetos/microbiologia , Fungos Mitospóricos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Southern Blotting , Clonagem Molecular , DNA Fúngico/análise , Genes Fúngicos/genética , Fungos Mitospóricos/enzimologia , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
11.
Mol Cells ; 10(6): 619-25, 2000 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-11211865

RESUMO

Flow cytometric analysis was systematically performed to optimize the concentration and duration of hydroxyurea (DNA synthesis inhibitor) and trifluralin (metaphase blocking reagent) treatments for synchronizing the cell cycle and accumulating metaphase chromosomes in barley root tips. A high metaphase index (76.5% in the root tip meristematic area) was routinely achieved. Seedlings of about 1.0-cm length were treated with 1.25 mM hydroxyurea for 14 h to synchronize the root tip meristem cells at the S/G2 phase. After rinsing with hydroxyurea, the seedlings were incubated in a hydroxyurea-free solution for 2 h and were treated with 1 microM trifluralin for 4 h to accumulate mitotic cells in the metaphase. The consistent high metaphase index depended on the uniform germination of seeds prior to treatment. High-quality and high-quantity isolated metaphase chromosomes were suitable for flow cytometric analysis and sorting. Flow karyotypes of barley chromosomes were established via univariate and bivariate analysis. A variation of flow karyotypes was detected among barley lines. Two single chromosome types were identified and sorted. Bivariate analysis showed no variation among barley individual chromosomes in AT and GC content.


Assuntos
Ciclo Celular/genética , Cromossomos/genética , Citometria de Fluxo/métodos , Hordeum/genética , Análise de Variância , Ciclo Celular/efeitos dos fármacos , Separação Celular/métodos , Separação Celular/normas , DNA de Plantas/fisiologia , Citometria de Fluxo/normas , Hordeum/citologia , Hidroxiureia/farmacologia , Cariotipagem/métodos , Metáfase/efeitos dos fármacos , Metáfase/genética , Raízes de Plantas/citologia , Raízes de Plantas/genética , Trifluralina/farmacologia
12.
IEEE Trans Biomed Eng ; 39(1): 19-25, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1572677

RESUMO

The purpose of this research was to develop quantitative measures for the assessment of laryngeal function using speech and electroglottographic (EGG) data. We developed two procedures for the detection of laryngeal pathology: 1) a spectral distortion measure using pitch synchronous and asynchronous methods with linear predictive coding (LPC) vectors and vector quantization (VQ) and 2) analysis of the EGG signal using time interval and amplitude difference measures. The VQ procedure was conjectured to offer the possibility of circumventing the need to estimate the glottal volume velocity wave-form by inverse filtering techniques. The EGG procedure was to evaluate data that was "nearly" a direct measure of vocal fold vibratory motion and thus was conjectured to offer the potential for providing an excellent assessment of laryngeal function. A threshold based procedure gave 75.9 and 69.0% probability of pathological detection using procedures 1) and 2), respectively, for 29 patients with pathological voices and 52 normal subjects. The false alarm probability was 9.6% for the normal subjects.


Assuntos
Eletrodiagnóstico/métodos , Glote/fisiopatologia , Doenças da Laringe/diagnóstico , Processamento de Sinais Assistido por Computador , Espectrografia do Som/métodos , Distúrbios da Voz/diagnóstico , Adulto , Idoso , Eletrodiagnóstico/normas , Estudos de Avaliação como Assunto , Feminino , Humanos , Doenças da Laringe/fisiopatologia , Masculino , Pessoa de Meia-Idade , Espectrografia do Som/normas , Vibração , Distúrbios da Voz/fisiopatologia
13.
J Endod ; 24(3): 184-6, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9558584

RESUMO

The purpose of this study was to evaluate the ability of mineral trioxide aggregate (MTA) and amalgam to seal furcal perforations in extracted human molars using an anaerobic bacterial leakage model. Furcal perforations were made in 39 maxillary and mandibular human molars with a high-speed bur. These were randomly divided into two experimental groups of 18, with the remaining three teeth used as positive controls. Experimental group 1 was repaired with MTA and group 2 with amalgam. Three additional teeth without perforations served as negative controls. A dual chamber anaerobic bacterial leakage model was assembled. Brain heart infusion broth with yeast extract, hemin, menadione, and the chromogenic indicator bromcresol purple was used as the culture broth for Fusobacterium nucleatum. Eight of 18 amalgam samples leaked, whereas none of the 18 MTA samples leaked. MTA was significantly better than amalgam in preventing leakage of F. nucleatum past furcal perforation repairs.


Assuntos
Compostos de Alumínio , Compostos de Cálcio , Amálgama Dentário , Infiltração Dentária/microbiologia , Fusobacterium nucleatum/fisiologia , Óxidos , Materiais Restauradores do Canal Radicular , Silicatos , Combinação de Medicamentos , Defeitos da Furca/microbiologia , Defeitos da Furca/terapia , Humanos , Técnicas In Vitro , Mandíbula , Maxila , Dente Molar , Selantes de Fossas e Fissuras , Distribuição Aleatória
14.
J Endod ; 24(4): 233-5, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9641124

RESUMO

The majority of bacteria associated with infections of endodontic origin are strict anaerobes. The purpose of this study was to develop an endodontic microleakage model using strict anaerobic bacteria in a two-chamber system. Nine species of anaerobic bacteria were tested for viability and detection by either turbidity or color change of the broth. A survey of pH chromogenic substrates revealed that bromcresol purple (pH 5.2 = yellow, pH 6.8 = purple) could be used as a chromogenic indicator to detect the growth of anaerobic bacteria. Peptone-yeast extract-glucose broth (PYG) and brain heart infusion broth (BHI) were each used alone and with bromcresol purple (bpPYG, bpBHI) in this study. Fusobacterium nucleatum and F. necrophorum were viable in all four media for > 2 wk and produced both turbidity and a color change after only 1 day of incubation. Veillonella parvula in either bpBHI or BHI and Peptostreptococcus anaerobius in either bpPYG or BHI were viable for > 2 wk and showed a color change or turbidity after 1 or 2 days. The results indicate that leakage of strict anaerobes may be evaluated in a two-chamber system.


Assuntos
Bactérias Anaeróbias/isolamento & purificação , Infiltração Dentária/microbiologia , Doenças da Polpa Dentária/microbiologia , Actinomyces/crescimento & desenvolvimento , Actinomyces/isolamento & purificação , Bactérias Anaeróbias/crescimento & desenvolvimento , Púrpura de Bromocresol , Meios de Cultura , Infiltração Dentária/diagnóstico , Cultura em Câmaras de Difusão , Fusobacterium/crescimento & desenvolvimento , Fusobacterium/isolamento & purificação , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Modelos Biológicos , Peptostreptococcus/crescimento & desenvolvimento , Peptostreptococcus/isolamento & purificação , Porphyromonas/crescimento & desenvolvimento , Porphyromonas/isolamento & purificação , Prevotella/crescimento & desenvolvimento , Prevotella/isolamento & purificação , Veillonella/crescimento & desenvolvimento , Veillonella/isolamento & purificação
15.
J Endod ; 25(6): 413-5, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10530240

RESUMO

Black-pigmented bacteria (BPB) have been associated with endodontic infections. The purpose of this study was to evaluate further the presence of BPB with the clinical signs and symptoms associated with endodontic infections. Microbial samples were collected from the root canals of 40 intact teeth with necrotic pulps and apical periodontitis. Conventional laboratory methods were used for identification of the strains of BPB isolated in pure culture. In addition, the polymerase chain reaction and specific primers for 16S r-RNA genes were used to differentiate Prevotella nigrescens from Prevotella intermedia. Twenty-two (55%) samples were positive for the growth of BPB. Of those, 11 of 22 (50%) were identified as P. nigrescens, 8 of 22 (36%) were P. intermedia, 2 of 22 (9%) were Porphyromonas gingivalis, and 1 of 22 (5%) was Prevotella melaninogenica. Sixteen of the 22 root canals positive for the growth of BPB were associated with purulent drainage either from the root canal or an associated sinus tract. Statistical analysis did not show a significant relationship for the presence of BPB with clinical signs and symptoms.


Assuntos
Necrose da Polpa Dentária/microbiologia , Periodontite Periapical/microbiologia , Prevotella/patogenicidade , Técnicas de Tipagem Bacteriana , DNA Bacteriano/análise , Humanos , Reação em Cadeia da Polimerase , Porphyromonas gingivalis/isolamento & purificação , Porphyromonas gingivalis/patogenicidade , Prevotella/isolamento & purificação , Prevotella intermedia/isolamento & purificação , Prevotella intermedia/patogenicidade , Prevotella melaninogenica/isolamento & purificação , Prevotella melaninogenica/patogenicidade
16.
J Endod ; 23(10): 620-3, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9587274

RESUMO

The occurrence of Prevotella intermedia and Prevotella nigrescens in endodontic infections was studied using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of whole cell protein to distinguish between the species. Previous studies have shown an association between black-pigmented bacteria (BPB) and endodontic infections and that Prevotella intermedia (previously known as Bacteroides intermedius) was the most commonly isolated BPB. Recently, however, strains identified as P. intermedia were shown to in fact be composed of two separate species, P. intermedia and P. nigrescens. Fifty-six strains of BPB isolated from endodontic infections and previously identified as P. intermedia were used in this study. Following SDS-PAGE, P. nigrescens showed a unique 18.6 kDa band that was used to differentiate P. nigrescens from P. intermedia. Of the 56 strains of BPB, 41 (73.2%) were identified as P. nigrescens and 15 (26.8%) as P. intermedia. This study confirms that P. nigrescens, and not P. intermedia, is the BPB most often isolated from infections of endodontic origin.


Assuntos
Infecções por Bacteroidaceae/microbiologia , Cavidade Pulpar/microbiologia , Doenças da Polpa Dentária/microbiologia , Prevotella intermedia/isolamento & purificação , Prevotella/isolamento & purificação , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Eletroforese em Gel de Poliacrilamida/métodos , Humanos , Dados de Sequência Molecular , Peso Molecular , Prevotella/genética , Prevotella intermedia/genética , Especificidade da Espécie
17.
J Endod ; 24(5): 356-8, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9641113

RESUMO

Black-pigmented bacteria (BPB) have been associated with infections of endodontic origin. The purpose of this study was to culture and identify BPB from the apical and coronal segments of infected root canals to understand better their ecological relationships. Teeth with a periapical radiolucency were extracted and immediately placed in reduced transport fluid for transport to an anaerobic chamber. Of 18 sampled roots, 12 were positive for the growth of BPB. Eight of the 12 roots with BPB had a carious exposure of the pulp chamber. Seven roots had Prevotella nigrescens in both the apical and the coronal segments. Six of these seven teeth had carious exposures of the pulp chamber. Of the 12 roots infected with BPB, six roots had two different species of BPB, with P. nigrescens always being one of the species. P. nigrescens was the most often isolated BPB from both the coronal and apical segments of infected root canals.


Assuntos
Cavidade Pulpar/microbiologia , Necrose da Polpa Dentária/microbiologia , Periodontite Periapical/microbiologia , Prevotella/isolamento & purificação , Contagem de Colônia Microbiana , Humanos , Porphyromonas gingivalis/isolamento & purificação , Ápice Dentário/microbiologia , Coroa do Dente/microbiologia
18.
J Endod ; 25(5): 324-8, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10530254

RESUMO

Isolates previously thought to be Prevotella intermedia have been shown to be a closely related species now known as Prevotella nigrescens. The purpose of this study was to determine the efficacy of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and polymerase chain reaction (PCR) to differentiate endodontic isolates of P. nigrescens from P. intermedia. Fifty-six strains of black-pigmented bacteria isolated from endodontic infections and conventionally identified as P. intermedia were used in this study. Using SDS-PAGE, novel polypeptide bands were used to differentiate P. nigrescens from P. intermedia. PCR was accomplished with specific primers for the 16S ribosomal RNA gene of both strains. Of 56 endodontic isolates, 41 (73%) strains were identified by SDS-PAGE as P. nigrescens and 15 (27%) strains as P. intermedia. Of the 41 strains of P. nigrescens identified by SDS-PAGE, PCR identified 37 strains as P. nigrescens. Restriction endonuclease digestion of amplified 16S ribosomal RNA genes indicated that the remaining four strains originally identified by SDS-PAGE as P. nigrescens were actually strains of Prevotella distinct from P. nigrescens and P. intermedia. Of 15 strains of P. intermedia identified by SDS-PAGE, PCR identified 14 strains as P. intermedia; but, one strain was identified as P. nigrescens. The results indicated that PCR was a more precise method than SDS-PAGE to differentiate P. intermedia from P. nigrescens. This study confirms that P. nigrescens is more commonly isolated in pure culture from endodontic infections than P. intermedia.


Assuntos
Prevotella/isolamento & purificação , Técnicas de Tipagem Bacteriana , DNA Bacteriano/análise , Doenças da Polpa Dentária/microbiologia , Eletroforese em Gel de Poliacrilamida , Humanos , Reação em Cadeia da Polimerase , Prevotella/genética , Prevotella intermedia/classificação , Prevotella intermedia/genética , Prevotella intermedia/isolamento & purificação
19.
J Antibiot (Tokyo) ; 50(6): 469-73, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9268001

RESUMO

New melanin synthesis inhibitors (MR566A and B) and six related known isocyanocyclopentenes were isolated from the fermentation broth of Trichoderma harzianum. The IC50 values of MR566A and B against mushroom tyrosinase were 1.72 and 47 microM, respectively. They inhibited melanin biosynthesis in B16 melanoma cells with MIC values of 0.1 and 2.2 microM, respectively. Also isolated from the same culture extract of T. harzianum was a new oxazole (MR93B), which showed no inhibitory activity against mushroom tyrosinase at a concentration of 1,000 microg/ml.


Assuntos
Ciclopentanos/metabolismo , Melaninas/biossíntese , Nitrilas/metabolismo , Trichoderma/classificação , Trichoderma/metabolismo , Animais , Basidiomycota/enzimologia , Ciclopentanos/isolamento & purificação , Ciclopentanos/farmacologia , Inibidores Enzimáticos/farmacologia , Fermentação , Melaninas/antagonistas & inibidores , Melanoma Experimental/metabolismo , Camundongos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Nitrilas/isolamento & purificação , Nitrilas/farmacologia , Streptomyces/efeitos dos fármacos , Streptomyces/metabolismo , Trichoderma/química , Células Tumorais Cultivadas/efeitos dos fármacos
20.
J Antibiot (Tokyo) ; 53(3): 248-55, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10819295

RESUMO

Chaetoatrosin A, a novel chitin synthase II inhibitor, was isolated from the culture broth of fungus F449, which was identified as Chaetomium atrobrunneum F449. Chaetoatrosin A was purified by solvent partition, silica gel, ODS, preparative TLC, and Sephadex LH-20 column chromatographies, consecutively. The structure of chaetoatrosin A was assigned as 1,8-dihydroxy-3(2-hydroxypropionyl)-6-methoxynaphthalene on the basis of various spectroscopic analyses including UV, IR, mass spectral, and NMR. Its molecular weight and formula were found to be 262 and C14H14O5, respectively. ,Chaetoatrosin A inhibited chitin synthase II by 50% at the concentration of 104 microg/ml in an enzyme assay system. This compound showed antifungal activities against Rhizoctonia solani, Pyricularia oryzae, Botrytis cinerea, Cryptococcus neoformans and Trichophyton mentagrophytes.


Assuntos
Antifúngicos/metabolismo , Chaetomium/metabolismo , Quitina Sintase/antagonistas & inibidores , Inibidores Enzimáticos/metabolismo , Naftóis/metabolismo , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Chaetomium/classificação , Chaetomium/enzimologia , Chaetomium/crescimento & desenvolvimento , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Fermentação , Fungos/efeitos dos fármacos , Humanos , Espectrometria de Massas/métodos , Micoses/microbiologia , Naftóis/química , Naftóis/farmacologia
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