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1.
Poult Sci ; 94(12): 2959-69, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26467005

RESUMO

Soybean hulls are a by-product of soybean processing for oil and meal production; Pleurotus eryngii stalk residues (PESR) are by-products of the edible portion of the fruiting body enriched in bioactive metabolites. This study evaluated the effects of co-fermented PESR and soybean hulls with Aureobasidium pullulans on performance and intestinal morphology in broiler chickens. The in vitro experimental results showed that xylananse and mannanase activity of solid-state fermented soybean hulls (100% SBH) and soybean hulls partially replaced with PESR (75:25, SHP) reached peak at day 12; solid-state fermentation (SSF) enhanced the total phenolic content and trolox equivalency in both products as well. Additionally, FSHP had higher xylotriose and mannobiose levels than fermented FSBH did. A total of 400 broilers (Ross 308) were assigned randomly into four groups receiving the basal diet (control) or the basal diet supplemented with 0.5% fermented SBH (0.5% FSBH), 0.5% fermented SBHP (0.5% FSHP) and 1.0% fermented SBHP (1.0% FSHP) until 35 d of age, respectively. Results demonstrated that 0.5% FSHP addition increased body weight gain as compared with corresponding normal diet fed control in birds during entire experimental period. Compared with the control group, 0.5% FSHP group significantly increased the ratio of lactic acid bacteria to Clostridium perfringens in ceca as well as ileum villus height and jejunum villus height/crypt depth ratio of 35 d old birds. In conclusion, 0.5% FSHP supplementation in the diet could obtain not only improved body weight gain, but optimal intestinal morphology by exerting its bioactive metabolite properties when fed to broilers.


Assuntos
Ração Animal/análise , Ascomicetos/metabolismo , Galinhas/anatomia & histologia , Galinhas/fisiologia , Glycine max/química , Pleurotus/química , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas/microbiologia , Dieta/veterinária , Suplementos Nutricionais/análise , Fermentação , Intestino Delgado/anatomia & histologia , Intestino Delgado/microbiologia , Pleurotus/metabolismo , Sementes/metabolismo
2.
Eur J Clin Nutr ; 66(4): 419-25, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21952693

RESUMO

BACKGROUND/OBJECTIVE: Previous clinical trials have documented that soy protein reduces low-density lipoprotein cholesterol and increases high-density lipoprotein (HDL) cholesterol compared with milk protein. However, the effect of soy protein on lipids compared with carbohydrate has not been not well studied. We examined the effect of soy and milk protein supplementation on lipids and lipoproteins compared with carbohydrate among adults without hypercholesterolemia. SUBJECTS/METHODS: We conducted a randomized, double-blind, 3-phase crossover trial among 352 US adults with serum total cholesterol level of <240 mg/dl from September 2003 to April 2008. Trial participants were assigned to 40 g/day supplementation of soy protein, milk protein or complex carbohydrate from wheat each for 8 weeks in random order with a 3-week washout period between interventions. Overnight fasting blood samples were collected at the termination of each intervention phase. RESULTS: Compared with carbohydrate, soy protein supplementation was significantly associated with a net change (95% confidence interval (CI)) in total cholesterol and total/HDL cholesterol ratio of -3.97 mg/dl (-7.63 to -0.31, P=0.03) and -0.12 (-0.23 to -0.01, P=0.03), respectively. Compared with milk protein, soy protein supplementation was significantly associated with a net change (95% CI) in HDL and total/HDL cholesterol ratio of 1.54 mg/dl (0.63 to 2.44, P=0.0009) and -0.14 (-0.22 to -0.05, P=0.001), respectively. Compared with carbohydrate, milk protein supplementation was significantly associated with a net change (95% CI) in HDL of -1.13 mg/dl (-2.05 to -0.22, P=0.02). CONCLUSIONS: This randomized controlled trial indicates that soy protein, but not milk protein, supplementation improves the lipid profile among healthy individuals.


Assuntos
HDL-Colesterol/sangue , LDL-Colesterol/sangue , Suplementos Nutricionais , Proteínas do Leite/administração & dosagem , Proteínas de Soja/administração & dosagem , Adulto , HDL-Colesterol/efeitos dos fármacos , LDL-Colesterol/efeitos dos fármacos , Estudos Cross-Over , Carboidratos da Dieta/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Hipercolesterolemia/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue
4.
Urol Int ; 85(1): 60-5, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20389054

RESUMO

PURPOSE: Previous studies showed that cranberries and related products may play a role in the prevention of urinary tract infection. The objective of this study is to investigate composite UmayC, a cranberry composite with the herbal extract Acrobio TS and Acrobio GL, in its effectiveness for catheter-associated lower urinary tract infection in an animal model. MATERIALS AND METHODS: A catheter was inserted into the bladder of rats with or without bacterial suspension. The rats were randomly assigned to the treated or the control group, which, respectively, received or did not receive UmayC in chowder diet. The voiding pattern was recorded using a metabolic cage. Spleen lysate cytokines were measured in both groups with Western blot analysis. RESULTS: The voiding pattern remained nearly the same in UmayC-treated rats, even when they had a bacterial suspension-filled catheter inserted. The most significant cytokine changes in these rats were decreased spleen interleukin-10 and interleukin-6, which may indicate a diminished host response to infection under UmayC herbal composite treatment. CONCLUSIONS: UmayC herbal composite can reduce bladder irritation caused by catheter-related infection. The host immune response to infection may also be altered and improved by the preventive effectiveness of Acrobio TS- and Acrobio GL-composited cranberry.


Assuntos
Anti-Infecciosos/farmacologia , Infecções Relacionadas a Cateter/prevenção & controle , Extratos Vegetais/farmacologia , Preparações de Plantas/farmacologia , Cateterismo Urinário/efeitos adversos , Animais , Infecções Relacionadas a Cateter/imunologia , Infecções Relacionadas a Cateter/microbiologia , Infecções Relacionadas a Cateter/fisiopatologia , Citocinas/metabolismo , Modelos Animais de Doenças , Combinação de Medicamentos , Feminino , Humanos , Projetos Piloto , Ratos , Ratos Sprague-Dawley , Baço/efeitos dos fármacos , Baço/imunologia , Urodinâmica/efeitos dos fármacos
5.
Ann Oncol ; 16(1): 97-101, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15598945

RESUMO

BACKGROUND: The purpose of this study was to compare quality of life and overall toxicity in patients with advanced non-small-cell lung cancer (NSCLC) treated with vinorelbine-gemcitabine (VG) or carboplatin-paclitaxel (Taxol) (CP). PATIENTS AND METHODS: A total of 165 previously untreated patients were randomized to the two regimens. Quality of life was assessed by the Lung Cancer Symptom Scale (LCSS). Overall toxicity and secondary efficacy end points were evaluated by standard WHO criteria. RESULTS: There was no significant difference in overall quality of life between the two treatments. Neutropenia, thrombocytopenia, peripheral neuropathy, and alopecia, were more common in the CP arm, whereas constipation was more frequent in the VG arm. Response rates were 14.6% in the VG arm and 16.9% in the CP arm. Median survival times were 7.8 and 8.6 months, and 1 year survival rates were 38.4% and 31.9%, respectively. CONCLUSIONS: Patients treated with VG experienced lower toxicity, but overall quality of life was similar in both arms. Efficacy seemed comparable between VG and CP. Our study shows that VG is a viable alternative to platinum-based chemotherapy in patients with advanced NSCLC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Desoxicitidina/análogos & derivados , Neoplasias Pulmonares/tratamento farmacológico , Vimblastina/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/patologia , Desoxicitidina/administração & dosagem , Feminino , Humanos , Infusões Intravenosas , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Qualidade de Vida , Análise de Sobrevida , Resultado do Tratamento , Vimblastina/administração & dosagem , Vinorelbina , Gencitabina
6.
Intensive Care Med ; 28(5): 636-41, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12029414

RESUMO

OBJECTIVES: To study the effect of hyperbaric oxygen therapy in alleviating acute lung injury induced by lipopolysaccharide (LPS) in rats. DESIGN AND INTERVENTIONS: The rats received an intraperitoneal injection of LPS (15 mg/kg). Animals were either breathing air at 1 ATA or subjected to hyperbaric oxygen (HBO(2)) therapy. The HBO(2) therapy was carried out in a hyperbaric chamber at a pressure of 3 ATA for 90 min. In another two groups, LPS-treated rats also received intraperitoneal injection of N(omega)-nitro-L-arginine (LNAME, 25 mg/kg) or L-N(6)-(iminoethyl)lysine (LNIL, 10 ml/kg). Another two groups of LPS-treated rats were subjected to HBO(2) exposure after the injection of L-NAME or L-NIL. MEASUREMENTS AND MAIN RESULTS: The bronchoalveolar lavage (BAL) was done into the left lung at 7.5 h after intraperitoneal injection of LPS. Parts of the right lung were excised for myeloperoxidase measurement, whereas the rest was collected for wet/dry ratio determination. LPS significantly increased the nitrite/nitrate (NO(x)(-)) concentration (34.4+/-15.7 vs 4.5+/-3.1 microM), LDH activity (66+/-17 vs 46+/-15 mAbs/min), and protein concentration (373+/-119 vs 180+/-90 mg/l) in the BAL fluid. Treatment with HBO(2) immediately after the injection of LPS enhanced the increase of NO(x)(-) production, but reduced the LDH and protein in BAL fluid to the control levels. Pretreatment with either L-NAME or L-NIL abolished the increase of NO(x)(-) in the BAL fluid and further elevated the LDH level and protein concentration. CONCLUSION: Our results suggested that HBO(2) alleviates the LPS-induced acute lung injury, which may be related to the enhancement of nitric oxide production.


Assuntos
Oxigenoterapia Hiperbárica , Lipopolissacarídeos/farmacologia , Pulmão/patologia , Lisina/análogos & derivados , Análise de Variância , Animais , Lavagem Broncoalveolar , Injeções Intraperitoneais , Lipopolissacarídeos/administração & dosagem , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Lisina/administração & dosagem , Lisina/farmacologia , Masculino , NG-Nitroarginina Metil Éster/administração & dosagem , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/metabolismo , Peroxidase/metabolismo , Ratos , Ratos Sprague-Dawley
7.
Bioorg Med Chem ; 9(12): 3165-72, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11711292

RESUMO

We have synthesized a series of 3-deoxy-3-heteromethyl derivatives of L-alpha-phosphatidyl-D-myo-inositol as part of our effort to develop specific, reversible inhibitors of phosphoinositide (PI) 3-kinase. Among various derivatives examined, phosphatidyl-D-3-deoxy-3-aminomethyl-myo-inositol displays the highest potency in inhibiting PI 3-kinase both in vitro and in cells. It effectively suppressed antigen-stimulated degranulation in mast cells (IC(50), 17 microM), suggesting a potential application of this PI 3-kinase inhibitor as a mast cell-stabilizing agent.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Inositol/síntese química , Inositol/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Androstadienos/farmacologia , Animais , Bioquímica/métodos , Degranulação Celular/efeitos dos fármacos , Células Cultivadas , Cromonas/farmacologia , Avaliação Pré-Clínica de Medicamentos , Concentração Inibidora 50 , Inositol/análogos & derivados , Inositol/química , Mastócitos/efeitos dos fármacos , Mastócitos/fisiologia , Morfolinas/farmacologia , Ratos , Relação Estrutura-Atividade , Wortmanina
8.
Phytochemistry ; 57(3): 349-59, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11393513

RESUMO

Five isoforms of beta-galactosidase (EC 3.2.1.23), designated as beta-galactosidases I-V, were isolated from five-day-old mung bean (Vigna radiata) seedlings. Beta-galactosidases II and III were purified to electrophoretic homogeneity by a procedure involving acid precipitation, ammonium sulfate fractionation, chromatography on diethylaminoethyl-cellulose (DEAE-Cellulose) and con A-Sepharose. and chromatofocusing. Beta-galactosidases I, II and III have the same molecular mass of 87 kDa. comprising two nonidentical subunits with molecular masses of 38 and 48 kDa, while beta-galactosidases IV and V have molecular masses of 45 and 73 kDa, respectively. All the enzymes were active against p-nitrophenyl-beta-D-galactoside, and to a lesser extent, p-nitrophenyl-alpha-L-arabinoside and p-nitrophenyl-beta-D-fucoside. The enzymes were inhibited by D-galactono-1,4-lactone, D-galactose, Hg2+, Ag+ and sodium dodecyl sulfate (SDS). Beta-galactosidases I, II and III were shown to be competitively inhibited by either D-galactono-1, 4-lactone or D-galactose. Isoforms I, II and III have a common optimal pH of 3.6, while isoforms IV and V have pH optima at 3.8 and 4.0, respectively. Isoelectric points of isoforms I, II and III were 7.7, 7.5 and 7.3, respectively. Double immunodiffusion analysis indicated that beta-galactosidases I, II, III and V are immunologically similar to each other, while beta-galactosidase IV shares partially identical antigenic determinants with the other four isoforms. The purified beta-galactosidases II and III were capable of releasing D-galactose residue from the hemicellulose fraction isolated from mung bean seeds.


Assuntos
Fabaceae/enzimologia , Plantas Medicinais , beta-Galactosidase/isolamento & purificação , beta-Galactosidase/metabolismo , Cromatografia de Afinidade , Cromatografia DEAE-Celulose , Inibidores Enzimáticos/farmacologia , Isoenzimas/química , Isoenzimas/isolamento & purificação , Isoenzimas/metabolismo , Cinética , Lactose/farmacologia , Peso Molecular , Monossacarídeos/farmacologia , Subunidades Proteicas , Especificidade por Substrato , beta-Galactosidase/química
9.
Changgeng Yi Xue Za Zhi ; 22(4): 598-603, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10695207

RESUMO

BACKGROUND: A retrospective analysis of enterovesical fistula treated at Chang Gung Memorial Hospital was conducted to determine the optimal diagnosis and management of this disease. METHODS: The records of 41 patients who presented from 1984 to 1996 and had a final diagnosis of enterovesical fistula were retrospectively reviewed. The etiology, symptoms on presentation, diagnostic tools, and modality of treatment were analyzed. RESULTS: The majority of these cases were associated with malignancy (38, 92.7%), and the others with diverticulitis (2, 4.9%) and iatrogenic causes (1, 2.4%). In those with malignancy, 15 patients (39.5%) were found to have tumor recurrence. The most frequent symptom in enterovesical fistula was fecaluria (58.5%), followed by abdominal pain (22%) and dysuria (14.6%). Diagnostic tools included the barium enema, cystography, and cystoscopy; these methods could identify the fistula in 63.2%, 60%, and 53.8% of the patients, respectively. Methods of management included diversion only (39%), one-stage fistula repair (36.6%), and watchful surveillance (24.4%). CONCLUSION: Enterovesical fistula should be considered if fecaluria, pneumaturia, or persistent non-specific urinary tract infection present as the initial complaint. A thorough surgery for a possible underlying malignancy is mandatory when confronted with enterovesical fistula, since the incidence of inflammatory bowel disease is low in this area. An abdominal computer tomography (CT) scan, barium enema, and cystogram can be useful diagnostic tools. Treatment of this entity should be individualized according to each patients clinical status.


Assuntos
Fístula Intestinal/terapia , Fístula da Bexiga Urinária/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Fístula Intestinal/diagnóstico , Fístula Intestinal/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fístula da Bexiga Urinária/diagnóstico , Fístula da Bexiga Urinária/etiologia
10.
J Gastroenterol Hepatol ; 13(4): 383-6, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9641301

RESUMO

A case of spontaneous isolated mesenteric fibromatosis presenting as megaduodenum is reported. The lesion was small, only 2 cm in its greatest diameter. However, because of its location near the ligament of Treitz and because of its characteristic infiltrative growth pattern, the tumour involved the distal duodenum and resulted in acute angulation and obstruction early in its course. We successfully resected the mass and the patient is in fair physical condition 6 months after operation.


Assuntos
Duodenopatias/diagnóstico , Fibroma/diagnóstico , Mesentério , Neoplasias Peritoneais/diagnóstico , Adulto , Sulfato de Bário , Duodenopatias/diagnóstico por imagem , Duodenopatias/patologia , Duodenopatias/cirurgia , Duodeno/diagnóstico por imagem , Duodeno/patologia , Duodeno/cirurgia , Enema , Fibroma/diagnóstico por imagem , Fibroma/patologia , Fibroma/cirurgia , Humanos , Masculino , Neoplasias Peritoneais/diagnóstico por imagem , Neoplasias Peritoneais/patologia , Neoplasias Peritoneais/cirurgia , Radiografia
11.
In Vitro Cell Dev Biol Anim ; 33(10): 796-802, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9466685

RESUMO

The behavior of vascular endothelial cells (EC) is an important factor in the processes involved in angiogenesis, but the regulatory mechanisms of angiogenesis, especially underlying the tubulogenesis by EC are not yet clear. Although a number of in vitro experimental models of tubulogenesis have been developed by use of cultured EC, most of those models are too complex to be easily handled and further, the culture media are usually supplemented with serum, creating problems in interpretation of experimental results. To generate a simple in vitro angiogenesis study model under serum-free culture conditions, we adapted a murine microvascular endothelial cell line, F-2, to a chemically defined medium, Cos Medium 001, and successfully established a subline of F-2, designated F-2C, which revealed a unique growth pattern. In Cos Medium 001, F-2C proliferates in a cobblestone pattern at an early growth stage, but, at a late growth stage, spontaneously differentiates to form three-dimensional honeycomblike tubular structures without the supplementation of any specific factors. The cell aggregation activity of F-2C in the presence of Ca2+ was much greater than that of F-2. The amount of subendothelial matrix deposited by F-2C was significantly higher than that by F-2, and increased prominently after the F-2C cells reached the differentiating stage of tubulogenesis. These findings indicate that F-2C is a new EC line in which tubulogenesis is spontaneously induced by the marked deposition of basement membrane analog to the subendothelial matrix and by the enhancement of presumable cadherin activity. We suggest that this cell line, F-2C, represents a simple and useful in vitro angiogenesis model.


Assuntos
Meios de Cultura Livres de Soro , Endotélio Vascular/citologia , Modelos Biológicos , Neovascularização Fisiológica , Animais , Cálcio/farmacologia , Adesão Celular , Agregação Celular , Diferenciação Celular , Divisão Celular , Linhagem Celular , Matriz Extracelular/fisiologia , Camundongos , Microcirculação/anatomia & histologia
12.
Neurosci Lett ; 75(2): 223-8, 1987 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-3106860

RESUMO

Turnover rates, as estimated from the accumulation of the intermediates, 3,4-dihydroxyphenylalanine (DOPA) and 5-hydroxytryptophan (5-HTP) following decarboxylase inhibition, were used to investigate the relationship between central catecholaminergic and serotonergic neurons and the development of hypertension in the one-kidney, one-clip renal hypertensive rats. Results indicated that at one week following clipping, 5-HTP accumulation was decreased in the posterior hypothalamus. At 5 weeks no changes were observed. At 20 weeks higher accumulations of both DOPA and 5-HTP were observed in the medulla oblongata while in the anterior hypothalamus DOPA accumulation was increased.


Assuntos
5-Hidroxitriptofano/análise , Química Encefálica , Di-Hidroxifenilalanina/análise , Hipertensão Renal/metabolismo , Animais , Catecolaminas/metabolismo , Cromatografia Líquida de Alta Pressão , Hipotálamo/análise , Bulbo/análise , Ratos , Ratos Endogâmicos , Serotonina/metabolismo
14.
Br J Haematol ; 52(4): 623-30, 1982 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6291576

RESUMO

Iron may affect both respiratory O2 transport and mitochondrial electron transport in the performance of muscle work. This study was designed to elucidate the molecular defect of iron-deficient work performance by identifying heretofore unmeasurable mitochondrial enzymes that are diminished by iron deficiency and may be restored by iron repletion. Female rats were made iron-deficient by dietary control and were repleted by oral iron. Iron deficiency reduced physical work capacity (treadmill running time), haemoglobin (Hb), and mitochondrial iron-sulphur (Fe-S) centres in heart and skeletal muscles; mitochondrial number was unaffected. Oral iron supplementation restored work capacity and Hb within 4 d to normal or near-normal levels, but in general Fe-S centres of mitochondria due to NADH dehydrogenase remained at iron-deficient levels. Subnormal concentrations of mitochondrial iron-dependent NADH dehydrogenase in muscle are not by themselves rate-limiting in work performance.


Assuntos
Anemia Hipocrômica/enzimologia , Redutases do Citocromo/metabolismo , Mitocôndrias Musculares/enzimologia , NADH Desidrogenase/metabolismo , Anemia Hipocrômica/tratamento farmacológico , Animais , Peso Corporal , Espectroscopia de Ressonância de Spin Eletrônica , Feminino , Ferro/uso terapêutico , Esforço Físico , Ratos , Ratos Endogâmicos
15.
Biochim Biophys Acta ; 699(2): 92-7, 1982 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-6924860

RESUMO

It has been previously shown that Clostridium sticklandii specifically synthesized three readily separable 75Se-labeled tRNAs, designated seleno-tRNAs I, II and III, and the partially purified seleno-tRNA II cochromatographed with L-prolyl-tRNA on DEAE-Sephadex A-50 (Chen, C.S. and Stadtman, T.C. (1980) Proc. Natl. Acad. Sci. U.S.A. 77, 1403-1407). In the present study a highly purified 75Se-labeled tRNA I was obtained by chromatography on benzoylated DEAE-cellulose, DEAE-Sephadex A-50 and Sepharose 4B. The 75Se-labeled tRNA I cochromatographed with an L-valine-accepting species on DEAE-Sephadex A-50 and Sepharose 4B. Addition of a 285-fold molar excess of unlabeled L-valine to the L-valine acceptor activity assay mixture markedly decreased the amount of L-[14C]valine bound to seleno-tRNA I.


Assuntos
Clostridium/genética , Aminoacil-RNA de Transferência/isolamento & purificação , RNA de Transferência/isolamento & purificação , Selênio/isolamento & purificação , Cromatografia por Troca Iônica , Aminoacil-RNA de Transferência/metabolismo , Valina/metabolismo
16.
Proc Natl Acad Sci U S A ; 77(3): 1403-7, 1980 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6154932

RESUMO

75Se-Labeled tRNAs were synthesized by Clostridium sticklandii cultures supplemented with 1 microM sodium [75Se]selenite or [75Se]selenocysteine. This process is highly specific for selenium; it occurred in the presence of 1.2 mM sodium sulfide and was not decreased by the further addition of a 500-fold molar excess of cysteine. The 75Se in these tRNAs was located in the polynucleotide portion of the molecules and not in esterified (alkali-labile) selenocysteine. Inhibition of cell multiplication by antibiotics that block either protein synthesis or DNA-dependent RNA synthesis did not prevent this 75Se incorporation. Three [75Se]tRNAs were separated from C. sticklandii cells labeled in the presence of chloramphenicol and were partially purified by chromatography on benzoylated DEAE-cellulose and DEAE-Sephadex A-50 columns. These were designated seleno-tRNAs I, II, and III according to their elution sequence from benzoylated DEAE-cellulose. Cochromatography of purified seleno-tRNA II on DEAE-Sephadex A-50 with an L-proline-accepting species suggests that it is a selenium-containing L-prolyl-tRNA.


Assuntos
RNA de Transferência/metabolismo , Selênio/metabolismo , Cromatografia , Clostridium/metabolismo , RNA Bacteriano/metabolismo , RNA de Transferência/isolamento & purificação , Aminoacil-RNA de Transferência/metabolismo
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