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1.
Am J Gastroenterol ; 88(5): 691-700, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8480734

RESUMO

The effect of ursodiol on the clinical and biochemical features, serum, urinary, and biliary bile acids was investigated over a 2-yr treatment period in 14 patients with primary biliary cirrhosis (stages II-IV). Pruritus and fatigue improved, and alkaline phosphatase and liver transferases declined significantly in all patients during therapy. In four patients, less inflammation was noted by liver biopsy after 2 yr, but histology of disease did not change. Serum and urinary bile acids were increased several-fold before treatment, with cholic acid predominating. Ursodiol accounted for 30% of biliary bile acids after administration (gallstone subjects approximately 50%), and was conjugated with glycine and taurine in a ratio of 7.3:1. However, in the endogenous bile acids, the ratio increased from 1.2:1 to only 2.1:1. About 6% unconjugated bile acids were secreted into the bile (healthy controls < 1%). Thus, in patients with primary biliary cirrhosis, a larger fraction of free bile acids and a higher proportion of taurine-conjugated bile acids are secreted into the bile, compared with healthy controls. Ursodiol improves symptoms and histology with lower biliary enrichment with this bile acid.


Assuntos
Ácidos e Sais Biliares/metabolismo , Cirrose Hepática Biliar/tratamento farmacológico , Fígado/metabolismo , Ácido Ursodesoxicólico/uso terapêutico , Bile/química , Método Duplo-Cego , Feminino , Humanos , Fígado/patologia , Cirrose Hepática Biliar/epidemiologia , Cirrose Hepática Biliar/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo
2.
J Lipid Res ; 33(9): 1403-7, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1402407

RESUMO

Gas-liquid chromatographic separation of C23, C24, C25, C26, and C27 bile alcohols with either 3 alpha, 7 alpha-dihydroxylated or 3 alpha, 7 alpha, 12 alpha-trihydroxylated ring system on two capillary columns, CP-Sil-19 CB and CP-Sil-5 CB, is described. Bile alcohols with two ring hydroxyl groups at 3 alpha- and 7 alpha-positions consistently showed larger retention times on CP-Sil-19 CB columns and smaller retention times on CP-Sil-5 CB columns than the corresponding bile alcohols with three ring hydroxyl groups at 3 alpha-, 7 alpha-, and 12 alpha-positions. Resolutions of all bile alcohols were better on CP-Sil-19 CB columns; however, we hope that the gas-liquid chromatographic characteristics on the two columns will be useful for better identification of bile alcohols in biological fluids.


Assuntos
Colestanóis/isolamento & purificação , Cromatografia Gasosa/métodos , Colestanóis/química , Colestanóis/urina , Humanos , Estrutura Molecular , Xantomatose/urina
3.
Gastroenterology ; 102(5): 1717-23, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1568582

RESUMO

Feedback regulation of derepressed hepatic bile acid biosynthesis was studied individually with glycocholic, glycodeoxycholic, and glycoursocholic acids by infusion into bile acid-depleted rabbits. Construction of a bile fistula drained the endogenous bile acid pool (90% glycodeoxycholic acid, 10% glycocholic acid) within 24 hours and elicited maximal bile acid synthesis after about 72 hours, at which time glycocholic acid became the only biliary bile acid (greater than 98%). Replacement of the bile acid pool with glycocholic acid or glycodeoxycholic acid at a rate equivalent to the hepatic endogenous bile acid flux inhibited endogenous biosynthesis by 40%. In contrast, glycoursocholic acid, the 7 beta-hydroxy epimer of glycocholic acid, failed to suppress synthesis. Hepatic bile acid depletion increased hydroxymethyglutary coenzyme A (HMG-CoA) reductase activity fourfold and cholesterol 7 alpha-hydroxylase activity threefold, which were reduced 48% and 51%, respectively, from their maximum levels during replacement with glycocholic acid. Glycodeoxycholic acid infusion depressed cholesterol 7 alpha-hydroxylase activity by 59% without reducing HMG-CoA reductase activity significantly. There was no significant change in the activity of either enzyme during glycoursocholic acid infusion. Biliary cholesterol and cholestanol secretion declined 13% and 53%, respectively, during glycocholic acid infusion, were not affected by glycodeoxycholic acid infusion, but increased 19% and 43%, respectively, during glycoursocholic acid infusion. These results show that in rabbits the feedback regulation of hepatic bile acid synthesis depends on the hepatic flux of the normally present endogenous bile acids glycocholic acid and glycodeoxycholic acid but does not respond to the 7 beta-hydroxy glycoursocholic acid. Glycocholic acid inhibits both HMG-CoA reductase and cholesterol 7 alpha-hydroxylase while glycodeoxycholic acid affects primarily cholesterol 7 alpha-hydroxylase. Thus, the regulation of bile acid synthesis may be mediated by both the availability of cholesterol substrate and the activity of the rate-determining enzyme for bile acid synthesis.


Assuntos
Ácidos e Sais Biliares/biossíntese , Ácidos Cólicos/farmacologia , Ácido Glicocólico/farmacologia , Ácido Glicodesoxicólico/farmacologia , Animais , Colesterol 7-alfa-Hidroxilase/análise , Hidroximetilglutaril-CoA Redutases/análise , Masculino , Coelhos
4.
Steroids ; 57(4): 162-6, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1519259

RESUMO

Synthesis of 25R- and 25S-diastereoisomers of 3 alpha,7 alpha-dihydroxy-5 beta-cholestan-26-oic acid from 3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholestan-26-oic acid is described. The 25S-diastereoisomer of 3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholestan- 26-oic acid was obtained by vigorous hydrolysis of the bile of Alligator mississippiensis followed by repeated crystallization of the hydrolysate, and the 25R-diastereoisomer was isolated by hydrolysis of the bile salts in bile of A mississippiensis with rat feces. Acetylation of the 25R- or 25S-diastereoisomer of methyl 3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholestan-26-oic acid under controlled conditions yielded the corresponding 3 alpha,7 alpha-diacetate in approximately 70% yield. The diacetate was quantitatively oxidized to methyl 3 alpha,7 alpha-diacetoxy-12-oxo-5 beta-cholestan-26-oate, which was converted into the 12-tosylhydrazone in approximately 58% yield. Reduction of the tosylhydrazone with sodium borohydride in acetic acid yielded the 25R- or the 25S-diastereoisomer of 3 alpha,7 alpha-dihydroxy-5 beta-cholestan-26-oic acid as the major product. Purification via column chromatography yielded the pure diastereoisomers in approximately 25% overall yield. The two diastereoisomers were resolved on thin-layer chromatography and high-performance liquid chromatography. When the bile of A mississippiensis was hydrolyzed with rat fecal bacteria, the 3 alpha,7 alpha-dihydroxy-5 beta-cholestan-26-oic acid isolated via chromatographic purification was shown to be the 25R-diastereoisomer.


Assuntos
Jacarés e Crocodilos/metabolismo , Bile/química , Colestanóis/química , Colestanóis/síntese química , Acetilação , Animais , Colestanóis/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Estereoisomerismo
5.
Hepatology ; 14(5): 838-47, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1937390

RESUMO

We investigated the effects of once-daily oral administration of 10 mg/kg ursodeoxycholic acid (generic name, ursodiol) on elevated serum enzyme activities, bilirubin, cholesterol, bile acids and symptoms in patients with primary sclerosing cholangitis. A 30-mo, open-label, pilot trial was designed to cover four periods: (a) 3 mo of pretreatment observation (period 1), (b) 6 mo on ursodiol (period 2), (c) 3 mo withdrawal of treatment (period 3) and (d) 18 mo of extended retreatment (period 4). Diagnosis was confirmed by cholangiography and liver biopsy specimens. We enrolled 12 patients with persistently elevated pretreatment alkaline phosphatase and gamma-glutamyltransferase levels (at least twice the upper limit of normal), and observed them for a median of 37 mo. Significant reductions in serum total cholesterol levels and in serum enzyme activities indicating cholestasis and hepatocellular injury occurred during ursodiol treatment in both treatment periods 2 and 4 and relapsed with treatment interruption in period 3. Elevated serum bilirubin and symptoms of disabling fatigue, pruritus and diarrhea were improved by ursodiol. Improvements have continued after 2 yr of treatment in 10 patients (1 patient had a transplantation after he relapsed on withdrawal of ursodiol therapy; another died of postoperative complications of colon resection for carcinoma). No other cases of clinical deterioration were observed in the retreatment period. The longer term reductions of alkaline phosphatase, transaminases, bilirubin and cholesterol after 2 yr of treatment were even greater than the initial reductions after 6 mo of treatment. These results justify initiation of larger, controlled clinical trials, with serial morphological evaluations of the liver and biliary tree.


Assuntos
Colangite Esclerosante/tratamento farmacológico , Ácido Ursodesoxicólico/uso terapêutico , Adulto , Idoso , Ácidos e Sais Biliares/sangue , Ácidos e Sais Biliares/urina , Colangite Esclerosante/complicações , Colangite Esclerosante/fisiopatologia , Feminino , Humanos , Lipídeos/sangue , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Fatores de Tempo
6.
J Oral Maxillofac Surg ; 47(12): 1248-55, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2479730

RESUMO

A clinicopathological, immunohistochemical, and ultrastructural study of 44 oral granular cell lesions was performed. A total of 35 mucosal granular cell tumors, 4 granular cell ameloblastomas, 1 lichen planus with granular cell change, and 3 congenital epulides of the newborn were studied. Pseudoepitheliomatous hyperplasia was found to occur in only a minority of these cases. Immunohistochemically, the majority of granular cell lesions were uniformly positive for S-100 protein and focally positive for vimentin in one half of the cases, suggestive of origin from a Schwann cell or a precursor mesenchymal cell. Congenital epulis of the newborn and central odontogenic granular cell tumor were negative for S-100 protein, epithelial membrane antigen (EMA), and prekeratin, suggesting a mesenchymal origin for these lesions.


Assuntos
Neoplasias Maxilomandibulares/patologia , Tumores Odontogênicos/patologia , Neoplasias da Língua/patologia , Adolescente , Adulto , Ameloblastoma/análise , Ameloblastoma/patologia , Ameloblastoma/ultraestrutura , Criança , Feminino , Neoplasias Gengivais/análise , Neoplasias Gengivais/congênito , Neoplasias Gengivais/patologia , Neoplasias Gengivais/ultraestrutura , Humanos , Hiperplasia , Imuno-Histoquímica , Neoplasias Maxilomandibulares/análise , Neoplasias Maxilomandibulares/ultraestrutura , Líquen Plano/metabolismo , Líquen Plano/patologia , Masculino , Pessoa de Meia-Idade , Doenças da Boca/metabolismo , Doenças da Boca/patologia , Tumores Odontogênicos/análise , Tumores Odontogênicos/ultraestrutura , Coloração e Rotulagem , Neoplasias da Língua/análise , Neoplasias da Língua/ultraestrutura
7.
Arch Pathol Lab Med ; 113(11): 1301-2, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2684092

RESUMO

A congenital oral duplication cyst of the ventral surface of the tongue was found to contain both gastrointestinal and respiratory epithelium. The literature is reviewed, with emphasis on the possible histogenesis of this extremely rare lesion, as well on the clinical differential diagnosis.


Assuntos
Coristoma/patologia , Cistos/patologia , Sistema Digestório , Sistema Respiratório , Neoplasias da Língua/patologia , Coristoma/congênito , Cistos/congênito , Epitélio/patologia , Humanos , Lactente , Masculino , Neoplasias da Língua/congênito
8.
Am J Med Genet ; 31(2): 391-4, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3232702

RESUMO

A 34-week stillborn infant had omphalocele, agenesis of the sternum and anterior rib cage, membranous diaphragms with eventration of the viscera, ectopia cordis with absence of the pericardium, and congenital heart defect. These findings are consistent with a diagnosis of Cantrell pentalogy. The presence of bilateral clubfeet, spina bifida, hydrocephalus, abnormal ears, and horseshoe kidneys suggested a chromosome abnormality. Chromosome analysis showed trisomy 18. Individuals with manifestations of Cantrell pentalogy deserve cytogenetic evaluation.


Assuntos
Anormalidades Múltiplas , Cromossomos Humanos Par 18 , Trissomia , Feminino , Morte Fetal , Humanos , Recém-Nascido , Gravidez
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