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1.
J Hum Nutr Diet ; 30(3): 302-308, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28150353

RESUMEN

BACKGROUND: In highly invasive diseases, metabolism commonly changes. Hypercatabolism is frequent in acute stroke, and nitrogen balance tends to be negative. However, there has been no study describing nitrogen balance in subacute and chronic stroke patients. The present study aimed to examine nitrogen balance in the subacute and chronic phases and to identify the factors related to it. METHODS: Nitrogen balance was calculated from the collected urine of 56 patients with subacute stroke [mean (SD) 53.8 (18.4) days post-stroke] who were admitted for rehabilitation for their first-ever ischaemic or nonsurgical haemorrhagic stroke. In the first experiment, their nitrogen balance was measured during the rehabilitation phase, and factors (type, severity of hemiparesis, activities of daily living, dysphagia and malnutrition status) related to it were evaluated. The second experiment was performed to describe the time course of nitrogen balance in 31 consecutive patients, with assessments made at admission and at discharge. RESULTS: Nitrogen balance was positive in all patients in the subacute phase. A significant difference was seen in nitrogen balance between high and low fat-free mass in male patients. In the chronic phase, nitrogen balance was positive in 96% of the patients. There was no significant difference in nitrogen balance between discharge and admission. CONCLUSIONS: In the subacute and chronic phases of stroke, it was confirmed that hypercatabolism had resolved and that intensive rehabilitation is possible in the convalescent period of stroke.


Asunto(s)
Trastornos de Deglución/diagnóstico , Desnutrición/diagnóstico , Nitrógeno/orina , Paresia/diagnóstico , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular/orina , Actividades Cotidianas , Enfermedad Aguda , Anciano , Enfermedad Crónica , Estudios Transversales , Metabolismo Energético , Femenino , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Alta del Paciente , Estudios Prospectivos , Descanso , Accidente Cerebrovascular/terapia
2.
Science ; 157(3795): 1452-4, 1967 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-5341323

RESUMEN

The 40S ribonucleoprotein particle in Escherichia coli cells, accumulated in the presence of a low concentration of chloramphenicol, lacks at least four ribosomal structural protein components which are present in the mature 50S ribosomal subunit. The 40S ribonucleoprotein prepared by exposing the 50S ribosomal subunit to a concentrated lithium chloride solution may also be deficient in the same protein components.


Asunto(s)
Proteínas Bacterianas/análisis , Escherichia coli/citología , Nucleoproteínas/análisis , Ribosomas/análisis , Isótopos de Carbono , Centrifugación por Gradiente de Densidad , Cloranfenicol/farmacología , Cloruros/farmacología , Cromatografía , Litio/farmacología , Lisina/metabolismo , Metilcelulosa , Tritio
3.
Science ; 162(3853): 576-8, 1968 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-4886608

RESUMEN

Erythromycin combines with 50S ribosomal subunit of an erythromycin-sensitive Escherichia coli (strain Q13), while ribosomes from an erythromycin-resistant mutant from this strain have little affinity for the antibiotic. A protein component of the 50S subunit of the mutant strain is distinct from that of the parent Q13 strain.


Asunto(s)
Proteínas Bacterianas/análisis , Farmacorresistencia Microbiana , Eritromicina/metabolismo , Escherichia coli/metabolismo , Ribosomas/metabolismo , Isótopos de Carbono , Sistema Libre de Células , Cromatografía por Intercambio Iónico , Escherichia coli/citología , Escherichia coli/efectos de los fármacos , Genética Microbiana , Lisina , Metilcelulosa , Mutación , Farmacogenética , Unión Proteica , Tritio , Triptófano
4.
Mol Cell Biol ; 4(11): 2535-9, 1984 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6083442

RESUMEN

Specific antibodies directed against Drosophila melanogaster acidic ribosomal protein S14 were used in a comparative study of eucaryotic and procaryotic ribosomes by immunoblotting and enzyme-linked immunosorbent assays. Common antigenic determinants and, thus, structural homology were found between D. melanogaster, Saccharomyces cerevisiae (S25), rabbit liver (S12), Bacillus subtilis (S6), and Escherichia coli (S6) ribosomes.


Asunto(s)
Proteínas Ribosómicas/inmunología , Animales , Bacillus subtilis/inmunología , Reacciones Cruzadas , Drosophila melanogaster/inmunología , Epítopos/inmunología , Escherichia coli/inmunología , Hígado/inmunología , Conejos , Saccharomyces cerevisiae/inmunología , Especificidad de la Especie
5.
Mol Cell Biol ; 10(12): 6544-53, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2247072

RESUMEN

The accurate and efficient translation of proteins is of fundamental importance to both bacteria and higher organisms. Most of our knowledge about the control of translational fidelity comes from studies of Escherichia coli. In particular, ram (ribosomal ambiguity) mutations in structural genes of E. coli ribosomal proteins S4 and S5 have been shown to increase translational error frequencies. We describe the first sequence of a ribosomal protein gene that affects translational ambiguity in a eucaryote. We show that the yeast omnipotent suppressor SUP44 encodes the yeast ribosomal protein S4. The gene exists as a single copy without an intron. The SUP44 protein is 26% identical (54% similar) to the well-characterized E. coli S5 ram protein. SUP44 is also 59% identical (78% similar) to mouse protein LLrep3, whose function was previously unknown (D.L. Heller, K.M. Gianda, and L. Leinwand, Mol. Cell. Biol. 8:2797-2803, 1988). The SUP44 suppressor mutation occurs near a region of the protein that corresponds to the known positions of alterations in E. coli S5 ram mutations. This is the first ribosomal protein whose function and sequence have been shown to be conserved between procaryotes and eucaryotes.


Asunto(s)
Escherichia coli/genética , Genes Bacterianos , Genes Fúngicos , Genes Supresores , Proteínas Ribosómicas/genética , Saccharomyces cerevisiae/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Prueba de Complementación Genética , Datos de Secuencia Molecular , Mutación , Mapeo Restrictivo , Homología de Secuencia de Ácido Nucleico
6.
Biochim Biophys Acta ; 1132(2): 195-8, 1992 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-1390890

RESUMEN

We isolated and sequenced YL16A and YL16B encoding ribosomal protein YL16 of Saccharomyces cerevisiae. The two nucleotide sequences within coding regions retain 91.1% identity, and their predicted sequences of 176 amino acids show 93.8% identity. Out of the ribosomal protein sequences from various organisms currently available, no counterpart to YL16 could be found.


Asunto(s)
Proteínas Fúngicas/genética , Proteínas Ribosómicas/genética , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Secuencia de Aminoácidos , Secuencia de Bases , Northern Blotting , Southern Blotting , ADN de Hongos , Genes Fúngicos , Datos de Secuencia Molecular , Mapeo Restrictivo
15.
J Mol Evol ; 29(3): 246-54, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2506358

RESUMEN

Sequence homologies among 34 chloroplast-type ferredoxins were examined using a computer program that quantitatively evaluates the extent of sequence similarity as a correlation coefficient. The resultant alignment contains six gaps representing insertions or deletions of some residues, all of which are located such that they precisely preserve the domains of structural fragments as determined by crystallographic data on Spirulina platensis ferredoxin. In the search for any total correlation between the chloroplast-type and 27 bacterial ferredoxins, 1891 comparison matrices prepared for possible combinations indicated that the bacterial basal sequence of 55 residues has been conserved evolutionarily in the chloroplast-type sequences corresponding to residue positions 36-90 of Spirulina platensis ferredoxin. In addition, the bacterial "connector sequence" region was found to be conserved. These findings strongly suggest that the bacterial and chloroplast-type ferredoxins descended from a common ancestor, and branched off after the bacterial gene duplication, whereas the chloroplast-type ferredoxins originally were generated by duplicating the already duplicated bacterial gene, i.e., by "double-duplication."


Asunto(s)
Secuencia de Aminoácidos , Bacterias/genética , Cloroplastos/metabolismo , Ferredoxinas/genética , Plantas/genética , Bacterias/metabolismo , Datos de Secuencia Molecular , Homología de Secuencia de Ácido Nucleico
16.
Biochemistry ; 18(19): 4191-6, 1979 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-385049

RESUMEN

A method for preparation of a large amount of ribosomal subunits from Saccharomyces cerevisiae by a Ti-15 zonal rotor is described. The proteins of the small subunits (ca. 50 000 A260 units) were separated into 22 fractions by chromatography on carboxymethylcellulose columns. Fourteen proteins were then purified from the ten chromatographic fractions by filtration through Sephadex G-100 or Sephacryl S--200. The isolated proteins are YP 6, YP 7, YP 9, YP 12, YP 14', YP 14'', YP 28, YP 38, YP 45, YP 50, YP 52, YP 58, YP 63, and YP 70. The molecular weight and amino acid compositions of these proteins are presented.


Asunto(s)
Proteínas Ribosómicas/análisis , Saccharomyces cerevisiae/análisis , Aminoácidos/análisis , Centrifugación Zonal/métodos , Cromatografía por Intercambio Iónico , Peso Molecular , Proteínas Ribosómicas/aislamiento & purificación
17.
Mol Gen Genet ; 162(3): 259-68, 1978 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-355832

RESUMEN

The cytoplasmic 80s ribosomal proteins from the cells of yeast Sachharomyces cerevisiae were analysed by SDS two-dimensional polyacrylamide gel electrophoresis. Seventyfour proteins were identified and consecutively numbered from 1 to 74. Upon oxidation of the 80s proteins with performic acid, ten proteins (no. 15, 20, 35, 40, 44, 46, 49, 51, 54 and 55) were dislocated on the gel without change of the total number of protein spots. Five proteins (no. 8, 14, 16, 36 and 74) were phosphorylated in vivo as seen in 32P-labelling experiments. The large and small subunits separated in low magnesium medium were analyzed by the above gel electrophoresis. At least forty-five and twenty-eight proteins were assumed to be in the large and small subunits, respectively. All proteins found in the 80s ribosomes, except for no. 3, were detected in either subunit without appearance of new spots. The acidic protein no. 3 seems to be lost during subunit dissociation.


Asunto(s)
Proteínas Ribosómicas/aislamiento & purificación , Saccharomyces cerevisiae/metabolismo , Autorradiografía , Electroforesis en Gel de Poliacrilamida/métodos , Peso Molecular , Ribosomas/metabolismo , Dodecil Sulfato de Sodio
18.
J Mol Evol ; 26(3): 257-67, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3129571

RESUMEN

Sequence homologies of 27 bacterial ferredoxins were examined using a computer program that quantitatively evaluates extent of similarity as a correlation coefficient. The results of a similarity search among the sequences demonstrated that the basal sequence consists of a pair of extremely similar segments of 26 amino acids connected by a three-amino acid group. The segment pairs, which would have arisen from gene duplication, are termed the first and second units. Because of the gene duplication, the connector sequence appears to have been introduced as a structurally important chain reversal. Each of the two units contains four cysteine residues, which are inserted one by one among seven, two, two, three, and eight amino acid alignments, respectively. The bacterial ferredoxins were categorized with regard to basal constitution as follows: group 1, in which both units closely conform to the basal structure; group 2, in which the second unit is modified in a characteristic manner among members; group 3, in which the first unit is modified in a characteristic manner, while the conforming second unit is accompanied by a long accessory sequence; group 4, in which there are modifications before and/or after the units, of which the respective central domains remain nearly intact; and group 5, where only the former of two Fe:S cluster ligation sets of four cysteines is estimated to remain intact, whereas the latter set is extremely modified. It is noteworthy that throughout all bacterial ferredoxins, one of two cysteine sets never fails to be completely intact and, moreover, the connector of three amino acids also exists intact. Based on this grouping and on the correspondences among the groups, average correlation coefficients among all members were computed, and the respective evolutionary relationships were examined. The results supported the proposition that transposition had occurred in the Azotobacter-type ferredoxins of group 3.


Asunto(s)
Bacterias/genética , Evolución Biológica , Ferredoxinas/genética , Secuencia de Aminoácidos , Datos de Secuencia Molecular , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie
19.
Mol Gen Genet ; 195(3): 544-6, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-18782943

RESUMEN

Two proteins, YL41 and YL43, were isolated from 80S ribosomes of Saccharomyces cerevisiae by filtration through a Sephacryl S-200 column and by chromatography on a column of carboxymethylcellulose. Their amino acid compositions are presented. Twenty-four proteins including these two proteins were subjected to sequence analyses by automated Edman degradation. Amino-terminal amino acid sequences were determined for 17 proteins,YS3, YS9, YS23, YS24, YS29, YL6, YL8, YLll, YLI5,YL17, YL23, YL28, YL33, YL37, YL39, YL41, and YL43.YL41, which has a 72.7% lysine and arginine content, was found to be particular to eukaryotic ribosomes. The amino-termini of another seven proteins, YS2, YS5, YS8, YS12,YS13, YS20, and YS27, were suggested to be blocked. Comparison of the amino-terminal sequences with all other ribosomal protein sequences so far available indicates that YS9 shows sequence homology to rat liver ribosomal protein S8 (Wittmann-Liebold et al. 1979).


Asunto(s)
Proteínas Ribosómicas/aislamiento & purificación , Proteínas de Saccharomyces cerevisiae/aislamiento & purificación , Saccharomyces cerevisiae/química , Resinas Acrílicas , Secuencia de Aminoácidos , Animales , Cromatografía por Intercambio Iónico , Datos de Secuencia Molecular , Ratas , Proteínas Ribosómicas/química , Proteínas de Saccharomyces cerevisiae/química , Homología de Secuencia de Aminoácido
20.
Protein Seq Data Anal ; 3(1): 11-9, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2179947

RESUMEN

Recently reported P1, P2 and metabacteria line sequences of transposition-type 'A' proteins, equivalent to Escherichia coli ribosomal protein L7/L12, were examined using a correlation method which evaluates the sequence similarity quantitatively. As the sequences could be aligned along the alignment previously constructed for 25 various 'A' proteins, the inclusive alignment further supports the previous claims concerning the rule of "preservation units" and the transpositional regeneration for metabacterial and eukaryotic 'A' proteins. Yeasts contain multispecies of P1 and P2 line genes and their P1 line sequences show low correlation coefficient values compared to other P1 line sequences, indicating a great evolutionary distance between lower and higher eukaryotes. Five sequences of protein P0 from metabacteria, yeast, and human, of which about 20 residues at the C termini are homologous with those of their own transposition-type 'A' proteins, were similarly examined. The N-terminal three-quarters of the sequences align naturally and the first two-thirds of the alignment could involve the E. coli L10 (EL10) sequence. An alignment of the remaining sequences at the C termini was established, relying on the well-matching sequence similarities between the metabacteria 'A' protein and their P0 protein sequences. Finally, the C-terminal halves of P0 protein sequences corresponded with almost overall sequences of the transposition-type 'A' proteins. The gene fusion of a protein might have resulted in the formation of the P0 proteins. A coupling of this gene fusion and the transposition of prototype 'A' proteins may have given rise to the complementary molecular transformations required for the development toward higher organism cells.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Proteínas Bacterianas , Evolución Biológica , Escherichia coli , Proteínas Ribosómicas , Secuencia de Aminoácidos , Datos de Secuencia Molecular , Homología de Secuencia de Ácido Nucleico
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