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1.
Neurogastroenterol Motil ; 27(5): 705-16, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25809913

RESUMO

BACKGROUND: Probiotics can be beneficial in irritable bowel syndrome (IBS). Mosapride citrate, a selective 5-HT4 receptor agonist, stimulates gastrointestinal motility. We investigated the efficacy of combination therapy with probiotics and mosapride for non-diarrheal-type IBS. METHODS: Two hundred and eighty-five IBS patients were randomly assigned to either a combination of probiotics (Bacillus subtilis and Streptococcus faecium) and mosapride at one of four different doses or a placebo for 4 weeks. The primary outcome was the proportion of patients experiencing adequate relief (AR) of global IBS symptoms at week 4. The secondary outcomes included subject's global assessment (SGA) of IBS symptom relief, individual symptoms, stool parameters, and IBS-quality of life. KEY RESULTS: The proportion of AR at week 4 was significantly higher in all treatment groups compared to the placebo group (53.7% in group 1, 55.0% in group 2, 55.2% in group 3, 53.6% in group 4 [the highest dose], and 35.1% in placebo group, respectively, p < 0.05). The proportion of patients reporting 'completely or considerably relieved' in the SGA was higher in the treatment groups than in the placebo group. The abdominal pain/discomfort score in the treatment group 4 was more prominently improved compared with that of the placebo group. In patients with constipation-predominant IBS, the improvements in stool frequency and consistency were significantly higher in the treatment groups 4 and 1, respectively, than those in the placebo group. CONCLUSIONS & INFERENCES: Combination therapy with probiotics and mosapride is effective for relief of symptoms in patients with non-diarrheal-type IBS. The study has been registered in the US National Library of Medicine (http://www.clinicaltrials.gov, NCT01505777).


Assuntos
Benzamidas/administração & dosagem , Fármacos Gastrointestinais/administração & dosagem , Síndrome do Intestino Irritável/tratamento farmacológico , Morfolinas/administração & dosagem , Probióticos/administração & dosagem , Qualidade de Vida , Dor Abdominal/tratamento farmacológico , Dor Abdominal/etiologia , Adulto , Bacillus subtilis , Método Duplo-Cego , Quimioterapia Combinada , Enterococcus faecium , Feminino , Motilidade Gastrointestinal , Humanos , Síndrome do Intestino Irritável/complicações , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
2.
Br J Radiol ; 84(1007): e203-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22011822

RESUMO

The fat-forming variant of solitary fibrous tumour (SFT) was previously called lipomatous haemangiopericytoma and is a rare variant of solitary fibrous tumour. It predominantly occurs in the deep soft tissues of the retroperitoneum and thigh. Only a handful of cases involving the perineum, spine, thoracic wall and pelvic cavity have been reported in the radiological literature and the fat-forming variant of SFT involving the pleura has not been previously reported. Herein, we report the CT findings of a case of the fat-forming variant of SFT involving the pleura that was treated by excision. Chest CT showed a large lobulated heterogeneous fatty mass with a multifocal enhancing soft-tissue component in the left lower hemithorax. Although rare, the fat-forming variant of SFT of the pleura should be added to the differential diagnosis of fat-containing pleural soft-tissue tumours.


Assuntos
Dispneia/diagnóstico por imagem , Hemangiopericitoma/diagnóstico por imagem , Lipoma/diagnóstico por imagem , Pleura/diagnóstico por imagem , Neoplasias Retais/diagnóstico por imagem , Tumor Fibroso Solitário Pleural/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Diagnóstico Diferencial , Dispneia/etiologia , Hemangiopericitoma/complicações , Hemangiopericitoma/patologia , Humanos , Lipoma/complicações , Lipoma/patologia , Masculino , Pleura/patologia , Neoplasias Retais/complicações , Neoplasias Retais/patologia , Tumor Fibroso Solitário Pleural/complicações , Tumor Fibroso Solitário Pleural/patologia , Resultado do Tratamento
4.
Aliment Pharmacol Ther ; 31(11): 1237-47, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20222912

RESUMO

BACKGROUND: Rome III incorporates changes in the definition of functional gastrointestinal disorder that involve a 3-month recall time for symptoms, rather than 1-year. AIM: To validate a new version of the Talley-Bowel Disease Questionnaire (Talley-BDQ) and assess the impact of recall time period on the prevalence of symptoms. METHODS: A sample of community residents were randomly mailed a survey using 1-year (n = 396) or 3-month recall period (n = 374). We evaluated the reliability and the concurrent validity of the two versions of the questionnaire. The proportions of subjects reporting symptoms in the two versions were compared. RESULTS: The median (IQR) kappa on symptom-related questions was 0.70 (0.57-0.76) from the 1-year version and 0.66 (0.56-0.77) from the 3-month version. A median kappa of 0.39 (0.19-0.70) and 0.58 (0.39-0.73) was observed for concurrent validation of the 1-year and 3-month versions respectively. Except for gastro-oesophageal reflux symptoms, no differences were observed on the prevalence of clinically relevant symptoms. CONCLUSION: The revised Talley-BDQ is reliable, with excellent reproducibility and validity. There were few differences in reported symptom rates between the 3-month and 1-year recall time versions of the questionnaire. A 1-year recall time may more efficiently capture infrequent or subtle symptoms.


Assuntos
Gastroenteropatias/diagnóstico , Inquéritos e Questionários/normas , Gastroenteropatias/epidemiologia , Humanos , Prevalência , Reprodutibilidade dos Testes , Fatores de Tempo
5.
Aliment Pharmacol Ther ; 26(3): 453-61, 2007 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17635380

RESUMO

BACKGROUND: Gastro-oesophageal reflux disease (GERD) and irritable bowel syndrome may occur more often than expected by chance, but little community data exists and risk factors are unknown. AIM: To determine prevalence and risk factors for overlap of GERD and irritable bowel disease. METHODS: Population-based, cross-sectional survey was conducted by mailing a valid symptom questionnaire to eligible residents of Olmsted County, MN, aged 30-95 years. Irritable bowel syndrome were defined by Rome III; GERD was defined by weekly or more frequent heartburn and/or acid regurgitation. RESULTS: 2298 questionnaires returned (women 52%, 55% response). Irritable bowel syndrome and GERD occurred together more commonly than expected by chance; the prevalence of irritable bowel syndrome-GERD overlap, GERD alone and irritable bowel syndrome alone were 3%, 15% and 5% in men, and 4%, 14% and 10% in women, respectively. Predictors of irritable bowel syndrome-GERD overlap vs. irritable bowel syndrome alone, and separately, GERD alone, were insomnia (OR 1.3, 95% CI: 1.06-1.70; OR 1.5, 95% CI: 1.13-1.90, respectively) and frequent abdominal pain (OR 3.9, 2.2-6.7; OR 1.8, 1.02-3.2, respectively). An additional predictor of irritable bowel syndrome-GERD overlap vs. GERD alone was higher somatization (OR 1.7, 1.1-2.4) and for irritable bowel syndrome-GERD overlap vs. irritable bowel syndrome alone was a higher body mass index (OR 1.0, 1.003-1.07). CONCLUSIONS: Irritable bowel syndrome and GERD overlap is common in the population and does not occur by chance.


Assuntos
Refluxo Gastroesofágico/epidemiologia , Síndrome do Intestino Irritável/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco
6.
Skin Pharmacol Appl Skin Physiol ; 15(4): 236-45, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12218285

RESUMO

OBJECTIVES: Recently the use of glycolic-acid-containing cosmetics has received increased public interest in their supposed ability to reduce wrinkles, roughness, age spots and other skin damage. However, the safety of such products when used excessively or chronically, especially by photosensitive people, is being questioned. The purpose of this study was to examine the effects of glycolic acid alone or in combination with UVB on skin damage and inflammatory response. METHOD: Guinea pigs were treated with glycolic acid (from 1 to 7 mg/cm(2)) alone or in combination with UVB (0.4 or 3 J/cm(2)) for 14 days. Skin damage was evaluated by scoring the skin irritation value by the method of Draize and by histopathological observations. Cyclooxygenase 2 (COX-2) expression and prostaglandin E(2) (PGE(2)) production were also assessed. RESULTS: Glycolic acid caused an increase in the level of skin damage in a dose- and time-dependent manner. Lower doses (1 and 3 mg/cm(2)) of glycolic acid mostly caused erythema and eschar, and these consequently formed scales, whereas higher doses (5 and 7 mg/cm(2)) of glycolic acid caused redness, edema and necrotic ulceration. Glycolic acid also increased the thickness of the epidermal layer, reduced the organization of the stratum corneum and eventually destroyed some parts of the epidermal layer at 7 mg/cm(2). UVB (0.4 and 3 J/cm(2)) caused redness and edema as well as reduced the integrity of the stratum corneum. Glycolic acid enhanced the UVB-induced skin damage. The magnitude of the damage caused by combined UVB and glycolic acid treatment was much greater than that caused by glycolic acid or UVB alone. Moreover, partial destruction of the epidermal layer was observed in skin treated with 3 J/cm(2) UVB and 3 mg/cm(2) glycolic acid. However, glycolic acid did not change the basal and UVB-induced PGE(2) production and COX-2 protein expression. CONCLUSION: These results show that glycolic acid causes skin damage in a dose- and time-dependent manner and that it enhances UVB-induced skin damage without accompanying PGE(2) production or COX-2 protein expression. Therefore, caution should be exercised by those using glycolic acid on a chronic basis or excessively. Moreover, those with photosensitive skins and those more exposed to the sun should be particularly careful.


Assuntos
Glicolatos/efeitos adversos , Ceratolíticos/efeitos adversos , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Animais , Ciclo-Oxigenase 2 , Derme/patologia , Dinoprostona/biossíntese , Epiderme/patologia , Feminino , Cobaias , Inflamação/etiologia , Isoenzimas/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Pele/metabolismo , Pele/patologia , Fatores de Tempo , Raios Ultravioleta/efeitos adversos
7.
J Korean Med Sci ; 16(6): 745-50, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11748356

RESUMO

Alcohol is oxidized to acetaldehyde by alcohol dehydrogenase (ADH) and cytochrome P-4502E1 (CYP2E1), and then to acetate by aldehyde dehydrogenase (ALDH). Polymorphisms of these ethanol-metabolizing enzymes may be associated with inter-individual difference in alcohol metabolism and susceptibility to alcoholic liver disease. We determined genotype and allele frequencies of ALDH2, CYP2E1, ADH2, and ADH3 in male Korean patients with alcoholic cirrhosis (n=56), alcoholics without evidence of liver disease (n=52), and nondrinkers (n=64) by using PCR or PCR-directed mutagenesis followed by restriction enzyme digestion. The prevalences of heterozygous ALDH2*1/*2 plus homozygous ALDH2*2/*2 in patients with alcoholic cirrhosis (7.1%) and alcoholics without evidence of liver disease (3.8%) were significantly lower than that in nondrinkers (45.3%). The c2 allele frequencies of the CYP2E1 in alcoholic cirrhosis, alcoholics without evidence of liver disease, and nondrinkers were 0.21, 0.20, and 0.20, respectively. Allele frequencies of ADH2*2 in the three groups were 0.78, 0.74, and 0.77 and those of ADH3*1 were 0.94, 0.98, and 0.95. Therefore, we confirmed the observation that the ALDH2*2 gene protects against the development of alcoholism. However, the development of cirrhosis in Korean alcoholic patients was not associated with polymorphisms of ethanol-metabolizing enzymes.


Assuntos
Álcool Desidrogenase/genética , Aldeído Desidrogenase/genética , Citocromo P-450 CYP2E1/genética , Cirrose Hepática Alcoólica/genética , Polimorfismo Genético , Adulto , Alcoolismo/enzimologia , Alcoolismo/genética , Aldeído-Desidrogenase Mitocondrial , Depressores do Sistema Nervoso Central/farmacocinética , Etanol/farmacocinética , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Coreia (Geográfico) , Cirrose Hepática Alcoólica/enzimologia , Masculino , Pessoa de Meia-Idade
8.
J Clin Gastroenterol ; 32(5): 441-3, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11319320

RESUMO

We report a case of microcystic (glycogen-rich) adenoma of the whole pancreas with coexistent pancreatic low-grade malignant islet cell tumor in a 29-year-old woman. She complained of nausea, vomiting, and growing abdominal mass. Abdominal computed tomography showed multiple cysts in the whole pancreas and a calcified solid mass in the pancreatic head. A Whipple's operation and total pancreatectomy with splenectomy was performed to treat pancreatic cystic neoplasm. The pancreas was entirely replaced by variable-sized, multilocular cysts, which were lined by a flattened-to-cuboidal glycogen-rich epithelium. Furthermore, in the head of the pancreas, a focal yellowish solid mass showed a positive reaction for chromogranin A and neuron-specific enolase. Careful examination of the pancreas is warranted in cases of microcystic adenoma to rule out a possible coexistent pancreatic malignancy.


Assuntos
Carcinoma de Células das Ilhotas Pancreáticas/patologia , Cistadenoma Seroso/patologia , Neoplasias Primárias Múltiplas , Neoplasias Pancreáticas/patologia , Adulto , Carcinoma de Células das Ilhotas Pancreáticas/diagnóstico por imagem , Carcinoma de Células das Ilhotas Pancreáticas/cirurgia , Cistadenoma Seroso/diagnóstico por imagem , Cistadenoma Seroso/cirurgia , Feminino , Humanos , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/cirurgia , Tomografia Computadorizada por Raios X
9.
J Gastroenterol Hepatol ; 16(12): 1336-40, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11851829

RESUMO

BACKGROUND AND AIM: Helicobacter pylori is considered as the major pathogen in Helicobacter pylori-associated gastroduodenal disease, but the mechanism of its action has not been fully explained. This study was performed to assess the reactive oxygen species activity and the damage in Helicobacter pylori-infected gastric mucosa. METHODS: Gastric biopsy specimens were obtained from 308 patients undergoing endoscopy. Gastric mucosal damage was assessed by using luminol enhanced chemiluminescence, thiobarbituric acid-reactive substance, and mucosal glutathione. RESULTS: The chemiluminescence and thiobarbituric acid-reactive substance-equivalent levels in the mucosa of patients with Helicobacter pylori-positive gastric mucosa (43.8 +/- 134.9 c.p.m./microg tissue, 157.0 +/- 96.2 nmol/g tissue, respectively) were significantly higher than in those with Helicobacter pylori-negative mucosa (6.8 +/- 20.3 c.p.m./microg tissue, 110.0 +/- 51.6 nmol/g tissue, respectively; P=0.000, P=0.016, respectively). The glutathione levels in the mucosa of patients with Helicobacter pylori-positive gastric mucosa (159.3 +/- 76.6 nmol/microg tissue) were significantly lower than in those with Helicobacter pylori-negative gastric mucosa (212.3 +/- 134.3 nmol/microg tissue; P=0.008). After the data were divided according to the presence of Helicobacter pylori, there were no significant differences in chemiluminescence, thiobarbituric acid-reactive substance, and glutathione among the different macroscopic findings within Helicobacter pylori-positive and -negative gastric mucosa. CONCLUSIONS: Helicobacter pylori infection plays a pathological role in many gastrointestinal diseases through excessive mucosal-reactive oxygen species production, pronounced membrane damage, and the depletion of gastric anti-oxidants.


Assuntos
Gastrite/metabolismo , Infecções por Helicobacter/metabolismo , Helicobacter pylori , Espécies Reativas de Oxigênio/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Mucosa Gástrica/metabolismo , Gastrite/microbiologia , Glutationa/análise , Humanos , Peroxidação de Lipídeos , Medições Luminescentes , Masculino , Malondialdeído/análise , Pessoa de Meia-Idade
10.
Artigo em Inglês | MEDLINE | ID: mdl-18238582

RESUMO

Resonant ultrasound spectroscopy (RUS) has been applied to the anisotropic elastic stiffness determination of SiC/Al composites and highly textured Zr-2.5 Nb alloys. To determine the elastic stiffness of anisotropic materials, the resonant frequencies of a rectangular parallelepiped specimen were measured and compared with the calculated frequencies based on the input data of the estimated stiffness, dimensions, and density. The initial estimates of the elastic stiffness of SiC/Al composites were calculated using the Mori-Tananka (MT) theory and the concept of effective aspect ratio of reinforcements. For highly textured Zr-2.5 Nb alloy, the initial estimates were obtained from its orientation distribution function, determined by X-ray diffraction, and the reported elastic stiffness of a single crystal zirconium. Through a comparison of calculated frequencies with those measured by RUS, elastic stiffness values have been determined very accurately by iteration and convergence processes.

11.
Korean J Intern Med ; 14(2): 27-33, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10461422

RESUMO

OBJECTIVES: The hepatotoxicity of acetaminophen is not a result of the parent compound but is mediated by its reactive metabolite N-acetyl-p-benzoquinone imine. Cytochrome P4502E1 (CYP2E1) is the principal enzyme of this biotransformation, which accounts for approximately 52% of the bioactivation in human microsomes. Recently, chlormethiazole a sedative drug, is reported to be an efficient inhibitor of CYP2E1 activity in human beings. In this study we wished to evaluate whether chlormethiazole, an inhibitor of CYP2E1, could prevent acetaminophen-induced liver injury in mice. METHODS: Acetaminophen, at doses ranging from 200 to 600 mg/kg, was injected into the peritoneum of female C57BL/6 inbred mice fasted for four hours. Chlormethiazole (60 mg/kg) or 5% dextrose water was given 30 min before or 2 h after acetaminophen. Serum aminotransferase activities, histologic index score, survival rate and hepatic malondialdehyde levels were compared. RESULTS: Pretreatment with chlormethiazole 30 min before 400 mg/kg of acetaminophen completely inhibited acetaminophen-induced liver injury (median 118.5 U/L, range 75 to 142 vs. 14,070 U/L, range 5980 to 27,680 for AST; 49 U/L, range 41 to 64 vs. 15,330 U/L, range 13,920 to 15,940 for ALT). In mice receiving chlormethiazole 2 h after acetaminophen, the mean AST and ALT levels were also less elevated, reaching only 20% of the value of acetaminophen-only group. These protective effects were confirmed histologically. Whereas more than 50% of mice died at 500 mg/kg of acetaminophen, all the mice pretreated with chlormethiazole survived at the same dose. CONCLUSION: Chlormethiazole effectively reduces acetaminophen-induced liver injury in mice. Further studies are needed to assess its role in humans.


Assuntos
Acetaminofen/toxicidade , Analgésicos não Narcóticos/toxicidade , Clormetiazol/farmacologia , Hipnóticos e Sedativos/farmacologia , Fígado/efeitos dos fármacos , Fígado/lesões , Acetaminofen/antagonistas & inibidores , Acetaminofen/metabolismo , Analgésicos não Narcóticos/antagonistas & inibidores , Analgésicos não Narcóticos/metabolismo , Animais , Inibidores do Citocromo P-450 CYP2E1 , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
12.
Am J Vet Res ; 60(4): 468-72, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10211691

RESUMO

OBJECTIVE: To serotype an enterotoxin gene from Escherichia coli isolated from cows, pigs, and chickens in Korea. SAMPLE POPULATION: Isolates from 37 cows with mastitis, 51 diarrheic pigs, and 5 diarrheic chickens. PROCEDURE: Serogroups and serotypes were identified by slide agglutination testing, using pathogenic E coli sera. Detection of E coli enterotoxins by use of reversed passive latex agglutination and ELISA was compared by proving existence of the gene by polymerase chain reaction (PCR) analysis. RESULTS AND CONCLUSIONS: Detection of E. coli enterotoxin by either method was positive for 1 strain (O20:H10; heat-labile enterotoxin [LT+], heat-stable enterotoxin [STa+]; isolation rate, 2%) and 3 other strains (O111:H10, O119:H9, and O125:H6, STa+; isolation rate, 5.9%) isolated from fecal specimens obtained from diarrheic pigs. The E coli enterotoxin genes were identified by use of PCR analysis in 1 strain containing the 417- and 163-base pair (bp) genes (LT+, Sta+; O20:H10) and in 3 strains containing only the 163-bp gene (STa+; O111:H10, O119:H9, and O125:H6). CLINICAL RELEVANCE: Serotyping of E coli enterotoxin may be used to analyze patterns of transmission among species of domestic animals.


Assuntos
Bovinos/microbiologia , Galinhas/microbiologia , Enterotoxinas/genética , Escherichia coli/classificação , Sorotipagem/veterinária , Suínos/microbiologia , Animais , Diarreia/microbiologia , Diarreia/veterinária , Enterotoxinas/análise , Ensaio de Imunoadsorção Enzimática/veterinária , Testes de Fixação do Látex/veterinária , Reação em Cadeia da Polimerase/veterinária
13.
Int J Food Microbiol ; 46(3): 231-41, 1999 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-10100903

RESUMO

Bifidobacteria have been previously shown to stimulate immune function and this may be mediated by macrophages. The RAW 264.7 cell line was used here as a macrophage model to assess the effects of human and commercial Bifidobacterium isolates on the production nitric oxide (NO), hydrogen peroxide (H2O2) and the cytokines IL-6 and tumor necrosis factor (TNF)-alpha. Thirty three Bifidobacterium strains differentially stimulated the production of H2O2 NO, TNF-alpha, and IL-6 in a dose-dependent manner in 24-h cultures. In the presence of lipopolysaccharide (LPS) the effects of bifidobacteria on NO and H2O2 were masked and were less pronounced at the later stage of incubation. Co-stimulation of macrophages with both LPS and Bifidobacterium increased the production of IL-6 synergistically. In contrast, LPS reduced the ability of the bifidobacteria-induced macrophages to produce TNF-alpha. Our results demonstrated that both human and commercial Bifidobacterium strains can stimulate H2O2, NO, TNF-alpha, and IL-6 production, and this effect was strain-dependent. The in vitro approaches employed here should be useful in further characterization of the effects of bifidobacteria on gastrointestinal and systemic immunity.


Assuntos
Bifidobacterium/fisiologia , Citocinas/biossíntese , Peróxido de Hidrogênio/metabolismo , Macrófagos/imunologia , Óxido Nítrico/biossíntese , Animais , Bifidobacterium/imunologia , Células Cultivadas , Citocinas/análise , Relação Dose-Resposta Imunológica , Ensaio de Imunoadsorção Enzimática , Fluorometria , Humanos , Peróxido de Hidrogênio/análise , Interleucina-6/análise , Interleucina-6/biossíntese , Lipopolissacarídeos/metabolismo , Macrófagos/metabolismo , Macrófagos/microbiologia , Camundongos , Óxido Nítrico/análise , Nitritos/análise , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/biossíntese , Regulação para Cima
14.
J Biol Chem ; 274(6): 3642-50, 1999 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-9920913

RESUMO

During base excision repair, DNA polymerase beta fills 1-6-nucleotide gaps processively, reflecting a contribution of both its 8- and 31-kDa domains to DNA binding. Here we report the fidelity of pol beta during synthesis to fill gaps of 1, 5, 6, or >300 nucleotides. Error rates during distributive synthesis by recombinant rat and human polymerase (pol) beta with a 390-base gap are similar to each other and to previous values with pol beta purified from tissues. The base substitution fidelity of human pol beta when processively filling a 5-nucleotide gap is similar to that with a 361-nucleotide gap, but "closely-spaced" substitutions are produced at a rate at least 60-fold higher than for distributive synthesis. Base substitution fidelity when filling a 1-nucleotide gap is higher than when filling a 5-nucleotide gap, suggesting a contribution of the 8-kDa domain to the dNTP binding pocket and/or a difference in base stacking or DNA structure imposed by pol beta. Nonetheless, 1-nucleotide gap filling is inaccurate, even generating complex substitution-addition errors. Finally, the single-base deletion error rate during processive synthesis to fill a 6-nucleotide gap is indistinguishable from that of distributive synthesis to fill a 390-nucleotide gap. Thus the mechanism of processivity by pol beta does not allow the enzyme to suppress template misalignments.


Assuntos
DNA Polimerase beta/metabolismo , Replicação do DNA , Animais , Sequência de Bases , DNA Polimerase beta/genética , DNA Recombinante , Mutação da Fase de Leitura , Humanos , Dados de Sequência Molecular , Ratos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
15.
EMBO J ; 15(24): 7060-9, 1996 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-9003781

RESUMO

Cyclin D-Cdk4/6 and cyclin A/E-Cdk2 are suggested to be involved in phosphorylation of the retinoblastoma protein (pRB) during the G1/S transition of the cell cycle. However, it is unclear why several Cdks are needed and how they are different from one another. We found that the consensus amino acid sequence for phosphorylation by cyclin D1-Cdk4 is different from S/T-P-X-K/R, which is the consensus sequence for phosphorylation by cyclin A/E-Cdk2 using various synthetic peptides as substrates. Cyclin D1-Cdk4 efficiently phosphorylated the G1 peptide, RPPTLS780PIPHIPR that contained a part of the sequence of pRB, while cyclins E-Cdk2 and A-Cdk2 did not. To determine the phosphorylation state of pRB in vitro and in vivo, we raised the specific antibody against phospho-Ser780 in pRB. We confirmed that cyclin D1-Cdk4, but not cyclin E-Cdk2, phosphorylated Ser780 in recombinant pRB. The Ser780 in pRB was phosphorylated in the G1 phase in a cell cycle-dependent manner. Furthermore, we found that pRB phosphorylated at Ser780 cannot bind to E2F-1 in vivo. Our data show that cyclin D1-Cdk4 and cyclin A/E Cdk2 phosphorylate different sites of pRB in vivo.


Assuntos
Quinases relacionadas a CDC2 e CDC28 , Proteínas de Transporte , Proteínas de Ciclo Celular , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/metabolismo , Proteínas de Ligação a DNA , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas , Sequência de Aminoácidos , Animais , Quinase 2 Dependente de Ciclina , Quinase 4 Dependente de Ciclina , Quinases Ciclina-Dependentes/química , Quinases Ciclina-Dependentes/isolamento & purificação , Ciclinas/química , Ciclinas/isolamento & purificação , Fatores de Transcrição E2F , Fator de Transcrição E2F1 , Humanos , Camundongos , Dados de Sequência Molecular , Fosforilação , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/isolamento & purificação , Proteína 1 de Ligação ao Retinoblastoma , Especificidade por Substrato , Fator de Transcrição DP1 , Fatores de Transcrição/genética , Células Tumorais Cultivadas
16.
Korean J Intern Med ; 10(2): 150-4, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7495775

RESUMO

OBJECTIVES: Accidental cisplatin overdose occurs with increasing frequency despite the safeguards taken in prescription and administration, since cisplatin has been used increasingly for the treatment of numerous malignancies. Accidentally, a 59-year-old male received massive cisplatin overdose of 300mg/m2. METHODS: Laboratory documentation included measurement of cisplatin concentrations by flameless atomic absorption spectroscopy (Varian, Spectra AA 300). RESULTS: Toxicities included severe emesis, myelosuppression, renal failure, mental deterioration with hallucination, dim vision and hepatic toxicity. Plasmapheresis was effective in lowering the platinum concentration from greatest 2979 ng/ml to 185 ng/ml and appeared to be of clinical benefit. Granulocyte-macrophage colony stimulating factor (GM-CSF) was used to ameliorate myelosuppression. The patient's renal function was restored 3 months later and partial response of esophageal cancer was obtained. CONCLUSIONS: Plasmapheresis was effective in lowering the platinum concentration in massive cisplatin overdose. This case heightens awareness to the possibility of accidental cisplatin overdose and the benefits of prompt management.


Assuntos
Antineoplásicos/intoxicação , Cisplatino/intoxicação , Plasmaferese , Cisplatino/isolamento & purificação , Overdose de Drogas/terapia , Humanos , Masculino , Pessoa de Meia-Idade
17.
J Bacteriol ; 174(23): 7841-3, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1447153

RESUMO

The mraR gene, which has a coding frame of 363 bp and lies close to and upstream of the ftsI gene of Escherichia coli, is involved in both cell division and cell lysis. It is thought to function in regulating the two distinct steps of the cell cycle, as two different one-base mutations in this unique gene caused different phenotypical changes in the cell. Comparison of nucleotide sequences of the mutant type mraR DNAs with the wild type suggested that filamentation of the cell was caused by a mutation in the putative start codon, whereas lysis of the cell was caused by a mutation which led to a change of one internal glutamate residue to lysine.


Assuntos
Escherichia coli/crescimento & desenvolvimento , Escherichia coli/genética , Genes Bacterianos/genética , Sequência de Aminoácidos , Sequência de Bases , Divisão Celular , Escherichia coli/citologia , Teste de Complementação Genética , Dados de Sequência Molecular
18.
J Bacteriol ; 173(3): 1021-6, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1846850

RESUMO

Amplification of the mraY gene, previously called open reading frame Y (ORF-Y, 1,080 bp), at 2 min in the chromosome map of Escherichia coli enhanced the activity of UDP-N-acetylmuramoyl-pentapeptide: undecaprenyl-phosphate phospho-N-acetylmuramoyl-pentapeptide transferase (EC 2.7.8.13). This enzyme catalyzes the formation of undecaprenyl-pyrophosphoryl-N-acetylmuramoyl-pentapeptide from UDP-N-acetylmuramoyl-pentapeptide and undecaprenyl-phosphate, the first step in the lipid cycle reactions in biosynthesis of bacterial cell wall peptidoglycans. The enhanced enzyme activity was sensitive to tunicamycin, and the amino tunicamycin-sensitive N-acetylglucosamine-1-phosphate transferase of Saccharomyces cerevisiae. Very probably mraY is the structural gene for the above enzyme.


Assuntos
Escherichia coli/genética , Fosfotransferases/genética , Transferases (Outros Grupos de Fosfato Substituídos) , Sequência de Aminoácidos , Escherichia coli/enzimologia , Genes Bacterianos , Cinética , Dados de Sequência Molecular , Fosfotransferases/química , Fosfotransferases/metabolismo , Plasmídeos , Mapeamento por Restrição , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Homologia de Sequência do Ácido Nucleico , Tunicamicina/farmacologia , Uridina Difosfato Ácido N-Acetilmurâmico/análogos & derivados , Uridina Difosfato Ácido N-Acetilmurâmico/metabolismo , Uridina Monofosfato/metabolismo
20.
J Bacteriol ; 171(11): 6375-8, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2509435

RESUMO

The Escherichia coli cell division gene ftsW (2 min) was cloned and sequenced. It encodes a hydrophobic protein(s) with 414 and/or 384 amino acid residues. The deduced amino acid sequence and the hydropathy profile of the protein showed high homology with those of the E. coli RodA protein functioning in determination of the cell shape and the Bacillus subtilis SpoVE protein functioning in spore formation. Probably similar functional membrane proteins are involved in these three cell cycle process.


Assuntos
Bacillus subtilis/genética , Proteínas de Bactérias/genética , Proteínas de Escherichia coli , Escherichia coli/genética , Genes Bacterianos , Proteínas de Membrana , Fator sigma , Fatores de Transcrição , Sequência de Aminoácidos , Bacillus subtilis/citologia , Bacillus subtilis/fisiologia , Sequência de Bases , Divisão Celular , Clonagem Molecular , Escherichia coli/citologia , Escherichia coli/fisiologia , Teste de Complementação Genética , Dados de Sequência Molecular , Família Multigênica , Conformação Proteica , Mapeamento por Restrição , Homologia de Sequência do Ácido Nucleico , Esporos Bacterianos/fisiologia
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