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1.
J Mol Biol ; 298(5): 859-73, 2000 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-10801354

RESUMO

Ribonuclease LE (RNase LE) from cultured tomato (Lycopersicon esculentum) cells is a member of the RNase T(2) family showing broad base specificity. The crystal structure of RNase LE has been determined at 1.65 A resolution. The structure consists of seven alpha-helices and seven beta-strands, belonging to an alpha+beta type structure. Comparison of the structure of RNase LE with that of RNase Rh, a microbial RNase belonging to the RNase T(2) family, reveals that while the overall folding topologies are similar to each other, major insertions and deletions are found at the N-terminal regions. The structural comparison, an amino acid sequence alignment of the RNase T(2) enzymes, and comparison of the disulfide-bonding pattern of these enzymes show that the structure of RNase LE shown here is the basic framework of the animal/plant subfamily of RNase T(2) enzymes (including a self-incompatibility protein called S-RNase), and the structure of RNase Rh is that of the fungal subfamily of RNase T(2) enzymes (including RNase T(2)). Subsequently, we superposed the active-site of the RNase LE with that of RNase Rh and found that (1) His39, Trp42, His92, Glu93, Lys96, and His97 of RNase LE coincided exactly with His46, Trp49, His104, Glu105, Lys108, and His109, respectively, of RNase Rh, and (2) two conserved water molecules were found at the putative P(1) sites of both enzymes. These facts suggest that plant RNase LE has a very similar hydrolysis mechanism to that of fungal RNase Rh, and almost all the RNase T(2) enzymes widely distributed in various species share a common catalytic mechanism. A cluster of hydrophobic residues was found on the active-site face of the RNase LE molecule and two large hydrophobic pockets exist. These hydrophobic pockets appear to be base binding sites mainly by hydrophobic interactions and are responsible for the base non-specificity of RNase LE.


Assuntos
Endorribonucleases/química , Proteínas de Plantas/química , Solanum lycopersicum/enzimologia , Sequência de Aminoácidos , Animais , Sítios de Ligação , Catálise , Sequência Conservada , Cristalografia por Raios X , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/classificação , Proteínas de Ligação a DNA/metabolismo , Dissulfetos/metabolismo , Endorribonucleases/classificação , Endorribonucleases/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/classificação , Proteínas Fúngicas/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Proteínas de Plantas/classificação , Proteínas de Plantas/metabolismo , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Relação Estrutura-Atividade , Especificidade por Substrato , Água/metabolismo
2.
J Clin Endocrinol Metab ; 76(1): 127-33, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8421076

RESUMO

We reported first in this study that human thyroid cell line NIM 1 established from a patient with papillary adenocarcinoma of the thyroid associated with hypercalcemia and peripheral neutrocytosis produced interleukin (IL)-1 alpha and IL-1 beta in the culture supernatant and cell lysate as detected by murine thymocyte proliferative response and enzyme-linked immunosorbent assay. Production of IL-1 alpha and IL-1 beta was further confirmed by the demonstration of IL-1 alpha and IL-1 beta messenger ribonucleic acid expression with Northern blot hybridization analysis. The in vitro growth of NIM 1 cells was inhibited by the addition of anti-IL-1 alpha and IL-1 beta antibody. The growth of NIM 1 cells was further enhanced by the addition of recombinant human IL-1 alpha and IL-1 beta, whereas this enhancement was also inhibited by the addition of anti-IL-1 antibody. IL-1 receptors were expressed on NIM 1 cells. These results suggest that IL-1 plays a regulatory role in the growth of NIM 1 cells by an autocrine mechanism.


Assuntos
Adenocarcinoma/patologia , Divisão Celular/efeitos dos fármacos , Interleucina-1/farmacologia , Neoplasias da Glândula Tireoide/patologia , Adenocarcinoma/genética , Adenocarcinoma/imunologia , Animais , Anticorpos/farmacologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Interleucina-1/genética , Interleucina-1/imunologia , Camundongos , Camundongos Nus , Transplante de Neoplasias , RNA Mensageiro/análise , Receptores de Interleucina-1/análise , Receptores de Interleucina-1/metabolismo , Proteínas Recombinantes/farmacologia , Linfócitos T/imunologia , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/imunologia , Transplante Heterólogo , Células Tumorais Cultivadas
3.
Gene ; 230(1): 91-9, 1999 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10196478

RESUMO

The highly heterogeneous rat hemoglobin system was investigated at the gene level. Two regions of the alpha-like globin gene cluster from a Wistar rat were isolated. Four lambda Dash recombinant clones carrying rat alpha-like globin genes were localized on two distinct gene regions. A region of approximately 16kb was found to contain the 5'-IIalpha1-psi theta 1-3' loci, and another of approximately 24kb the 5'-IIalpha2-psi theta2-psiI alpha3-3' loci. Both IIalpha1 and IIalpha2 are considered to be active, coding the IIalpha-globin chain. The nt sequences of IIalpha1 and IIalpha2 are identical except for six nt in the non-coding region. The psiI alpha3 locus is a truncated pseudogene. The putative promoter region of an alpha-like globin gene is joined directly to the third exon, homologous to that of Ialpha-globin cDNA. psi theta1 and psi theta2 are also pseudogenes, as evidenced by several deletions located in the protein-coding regions of these loci. The psi theta1 and psi theta2 loci exhibit extensive homology, but the restriction maps of these genes and their flanking regions differ considerably. Genomic Southern blot analyses of the total liver DNA from six rats showed the existence of three theta-globin-related genes, including psi theta1 and psi theta2. These results indicate that the two gene regions investigated are not allelic variants, but may be generated by block duplication. This is the first report of the existence of rodent theta-globin genes.


Assuntos
Globinas/genética , Animais , Sequência de Bases , Clonagem Molecular , Evolução Molecular , Duplicação Gênica , Dados de Sequência Molecular , Filogenia , Polimorfismo de Fragmento de Restrição , Regiões Promotoras Genéticas , Pseudogenes/genética , Ratos , Ratos Wistar , Mapeamento por Restrição , Alinhamento de Sequência
4.
J Biochem ; 89(1): 125-34, 1981 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6783630

RESUMO

1. A major glucoamylase [EC 3.2.1.3] of Aspergillus saitoi was purified by ultrafiltration followed by successive chromatography on DEAE-Sephadex, Ultrogel AcA 44 and SP-Sephadex. The purification achieved was 23-fold from crude extract with a yield of 21%. The purified enzyme, named Gluc M1, was proved homogeneous as judged by polyacrylamide gel electrophoresis, isoelectric focusing, ultracentrifugation, and also from the absence of the glycosidase activities detected in crude extract. 2. Gluc M1 was a glycoprotein containing 18% neutral sugar and 0.77% glucosamine, and its molecular weight was estimated to be about 90,000 by SDS-polyacrylamide gel electrophoresis and amino acid composition. The N-terminal amino acid was identified as alanine. 3. The pH optimum of Gluc M1 was 4.5 with soluble starch as a substrate. The enzyme was stable between pH 2.5 and 7.5 and retained full activity at temperatures up to 50 degrees C. The enzyme activity was inhibited by Hg2+ and, to a lesser extent, by Pb2+ and Mn2+. 4. The Km value for malto-oligomer markedly decreased with increasing chain length of substrate in glucose unit (n) and the Vmax value increased with n, thus resulting in the increase in the Vmax/Km value with n. The kinetic parameters for other substrates such as soluble starch, glycogen and isomaltose as well as the K1 values for some saccharides were also determined.


Assuntos
Aspergillus/enzimologia , Glucana 1,4-alfa-Glucosidase/isolamento & purificação , Glucosidases/isolamento & purificação , Aminoácidos/análise , Cátions Bivalentes , Glucana 1,4-alfa-Glucosidase/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Especificidade por Substrato
5.
J Biochem ; 113(4): 425-32, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8514732

RESUMO

Two ribonucleases (RNase Phya and RNase Phyb) were purified to homogeneity on SDS-PAGE from the culture filtrate of the fungus Physarum polycephalum. The apparent molecular weights of RNases Phya and Phyb were about 20,000. The pH optima of these two RNases were around 4.5-4.75. The RNases released mononucleotides from RNA in the order of 3'-GMP, 3'-AMP, and 3'-pyrimidine nucleotides. RNase Phya and RNase Phyb have the N-terminal amino acid sequences STSFD--- and KSTSF--, respectively. This finding and the similar amino acid compositions of both RNases indicated that they might share the same protein moiety except for the N-terminus Lys. The complete primary structure of RNase Phyb was determined, mostly by analysis of the peptides generated by trypsin, V8 protease, and lysylendopeptidase digestions. The molecular weight of the protein moiety was 19,704. The locations of four half cystine residues were almost superimposable on those in five known fungal RNase T2 family RNases, but two others were not. The sequence homology between RNase Phyb and five known fungal RNases amounted to 53-59 residues, which are concentrated around the three histidine residues, supposed to form the active site in enzymes of the RNase T2 family. However, the amino acid sequence of RNase Phyb more closely resembles those of plant RNases such as RNases from Nicotiana alata [McClure, B.A. et al. (1989) Nature 342, 955-957], tomato [RNase Le, Yost et al. (1991) Eur. J. Biochem. 198, 1-6], and Momoridica charantia [RNase MC1, Ide et al. (1991) FEBS Lett. 284, 161-164].


Assuntos
Physarum polycephalum/enzimologia , Ribonucleases/isolamento & purificação , Sequência de Aminoácidos , Animais , Cromatografia de Afinidade , Dicroísmo Circular , Eletroforese em Gel de Poliacrilamida , Hidrólise , Dados de Sequência Molecular , Proteínas/análise , Ribonucleases/metabolismo , Especificidade por Substrato
6.
J Biochem ; 91(1): 125-33, 1982 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6802809

RESUMO

1. In order to elucidate the structure-function relation of a glucoamylase [EC 3.2.1.3, alpha-D-(1 leads to 4)-glucan glucohydrolase] from Aspergillus saitoi (Gluc M1), the reaction of Gluc M1 with water-soluble carbodiimides was studied. 2. Gluc M1 was inactivated most effectively by 1-cyclohexyl-3-(2-morpholinyl-(4)-ethyl)carbodiimide (CMC) at pH 4.5. 3. Inactivation of Gluc M1 with [14C]CMC proceeded with the incorporation of about 12 CMC moieties. From the results of amino acid analysis, titration of SH group with Ellman's reagent and hydroxylamine treatment at pH 7.0, it was concluded that the crucial sites of modification were carboxyl groups of Gluc M1. 4. The CD spectrum of CMC-modified Gluc M1 (residual activity, ca. 9.8%) suggested that the gross conformation of the native enzyme was retained. 5. In the presence of maltose, when Gluc M1 was incubated with [14C]CMC, ca. 10 CMC moieties were incorporated with a simultaneous decrease in enzymatic activity (30%). The Gluc M1 modified in the presence of maltose was remodified with CMC after elimination of maltose. The CMC-modified Gluc M1 was inactivated completely with the incorporation of ca. 4 CMC moieties. 6. The logarithm of the half-life of the inactivation of Gluc M1 by CMC was a linear function of log [CMC] indicating that one carboxyl group among the modified ones was crucial for inactivation of Gluc M1. 7. The protection by maltose of Gluc M1 from inactivation and the increase in K1 values for maltose of CMC-modified Gluc M1's suggested that a crucial carboxyl group(s) was located near or on subsites 2 and 3.


Assuntos
Aspergillus/enzimologia , CME-Carbodi-Imida/farmacologia , Carbodi-Imidas/farmacologia , Glucana 1,4-alfa-Glucosidase/antagonistas & inibidores , Glucosidases/antagonistas & inibidores , CME-Carbodi-Imida/análogos & derivados , Dicroísmo Circular , Meia-Vida , Concentração de Íons de Hidrogênio , Cinética , Maltose/farmacologia , Relação Estrutura-Atividade
7.
J Biochem ; 91(5): 1661-8, 1982 May.
Artigo em Inglês | MEDLINE | ID: mdl-6807973

RESUMO

1. In order to elucidate the structure-function relation of a glucoamylase [EC 3.2.1.3, alpha-D-(1 leads to 4) glucan glucohydrolase] from Aspergillus saitoi (Gluc M1), the reaction of Gluc M1 with NBS was studied. 2. The tryptophan residues in Glu M1 were oxidized at various NBS/Gluc M1 ratios. The enzymatic activity decreased to about 80% of that of the native Gluc M1 with the oxidation of the first 2 tryptophan residues. The oxidation of these 2 tryptophan residues occurred within 0.2-0.5 s. On further oxidation of ca. 4-5 more tryptophan residues of Glu M1, the enzymatic activity of Gluc M1 decreased to almost zero (NBS/Gluc M1 = 20). Thus, the most essential tryptophan residue(s) is amongst these 4-5 tryptophan residues. 3. 7.5 tryptophan residues were found to be eventually oxidized with increasing concentrations of NBS up to NBS/Gluc M1 = 50. This value is comparable to the number of tryptophan residues which are located on the surface of the enzyme as judged from the solvent perturbation difference spectrum with ethylene glycol as perturbant. 4. In the presence of 10% soluble starch, about 5 tryptophan residues in Gluc M1 were oxidized at an NBS/Gluc M1 ratio of 20. The remaining activity of Glu M1 at this stage of oxidation was about 76%. On further oxidation, after removal of soluble starch, the enzymatic activity decreased to zero with the concomitant oxidation of 2 tryptophan residues. The results indicated that the essential tryptophan residue(s) is amongst these 2 tryptophans. 5. The UV difference spectrum induced by addition of maltose and maltitol to Gluc M1 showed 4 troughs at 281, 289, 297, and 303 nm. The latter 3 troughs were probably due to tryptophan residues of Gluc M1 and decreased with NBS oxidation.


Assuntos
Aspergillus/enzimologia , Bromosuccinimida/farmacologia , Glucana 1,4-alfa-Glucosidase , Glucosidases , Succinimidas/farmacologia , Fenômenos Químicos , Química , Glucana 1,4-alfa-Glucosidase/isolamento & purificação , Glucosidases/isolamento & purificação , Oxirredução/efeitos dos fármacos , Espectrofotometria/métodos , Relação Estrutura-Atividade , Triptofano/análise
8.
J Biochem ; 97(2): 633-41, 1985 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3924906

RESUMO

In order to elucidate the structure-function relationship of glucoamylases [EC 3.2.1.3, alpha-D-(1-4)-glucan glucohydrolase] from Aspergillus saitoi, the reaction of a minor component, Gluc M2 with 1-cyclohexyl-3-(2-morpholinyl-(4)-ethyl)carbodiimide metho p-toluenesulfonate (CMC) was studied at pH 4.5. Inactivation of Gluc M2 with [14C]CMC proceeded with the incorporation of about 5 CMC moieties. From the results of analyses of amino acid and sulfhydryl contents of CMC-modified Gluc M2 and the hydroxylamine treatment of the CMC-modified Gluc M2 at pH 7.0, it was concluded that the sites of CMC-modification were carboxylic acids of Gluc M2. In the presence of maltose, when Gluc M2 was treated with [14C]CMC, ca. 4 CMC moieties were incorporated with a simultaneous decrease in activity (30%). The Gluc M2 modified in the presence of maltose was re-modified with CMC after elimination of maltose. The CMC-modified Gluc M2 (70% activity) was inactivated completely with the further incorporation of ca. 2 CMC moieties. The logarithm of the half-life of the inactivation of Gluc M2 by CMC was a linear function of log[CMC] indicating that one carboxyl group among the modified ones was crucial for the inactivation of Gluc M2. From the results of these modification reactions, it was concluded that one or two carboxylic acids in Gluc M2 were crucial for the catalysis of glucoamylase from A. saitoi. Based on the analysis of the pH-profile of CMC inactivation of Gluc M2, the participation of a carboxylic acid having pKa 5.7 in the active site is proposed.


Assuntos
Aspergillus/enzimologia , CME-Carbodi-Imida , Carbodi-Imidas , Glucana 1,4-alfa-Glucosidase/metabolismo , Glucosidases/metabolismo , Aminoácidos/análise , CME-Carbodi-Imida/análogos & derivados , Fenômenos Químicos , Química , Dicroísmo Circular , Glucana 1,4-alfa-Glucosidase/antagonistas & inibidores , Glucana 1,4-alfa-Glucosidase/isolamento & purificação , Hidroxilamina , Hidroxilaminas , Cinética , Maltose/farmacologia , Especificidade por Substrato
9.
J Biochem ; 98(2): 341-7, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3934147

RESUMO

The mechanism of inhibition of the two glucoamylases from a Rhizopus sp. and Aspergillus saitoi by aminoalcohol derivatives was investigated. Hydrolysis of maltose by the glucoamylases was inhibited competitively by aminoalcohols at pH 5.0, and tris(hydroxymethyl)aminomethane, 2-amino-2-ethyl-1,3-propanediol and 2-aminocyclohexanol were relatively good inhibitors of the glucoamylases among the aminoalcohol derivatives tested. One hydroxyl group and an amino group in these inhibitors were indispensable for the inhibitory action, and the addition of other hydroxyl, amino or ethyl groups was enhancing. With an increase in pH from 4.0 to 6.0, the Ki values of the aminoalcohols decreased. This result suggested the participation of a carboxyl group, which was related to the glucoamylase activity and had a pKa of 5.7, in the binding of aminoalcohols. The UV difference spectra induced on binding of the aminoalcohol analogues with the glucoamylases may indicate a change of the environment of tryptophan residues to a slightly higher pH on inhibitor binding. The influence of aminoalcohols on the fluorescence intensity due to tryptophan residues and the CD-spectra of the glucoamylases was less than that of maltitol. Thus, the interaction of aminoalcohols with tryptophan residues in the glucoamylases might be less pronounced than that in the case of substrate analogues. The modes of binding of the aminoalcohols with the two glucoamylases were very similar. Therefore, the phenomenon might be a common feature of glucoamylases in general.


Assuntos
Amino Álcoois/farmacologia , Aspergillus/enzimologia , Glucana 1,4-alfa-Glucosidase/antagonistas & inibidores , Glucosidases/antagonistas & inibidores , Rhizopus/enzimologia , Dicroísmo Circular , Concentração de Íons de Hidrogênio , Cinética , Ligação Proteica , Conformação Proteica , Espectrofotometria Ultravioleta , Relação Estrutura-Atividade
10.
J Biochem ; 116(1): 26-33, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7798182

RESUMO

A guanine nucleotide-specific RNase (RNase Po1) was isolated from caps of the fruit bodies of Pleurotus ostreatus. RNase Po1 is most active towards RNA at pH 8.0. The effect of heating on the molar ellipticity at 210 nm of RNase Po1 showed that RNase Po1 is more stable than RNase T1. The primary structure of RNase Po1 was determined to be < ETGVRSCNCAGRSFTGTDVTNAIRSARAGGSGNYPHVYNNFEGFSFSCTPTFFEFPVFRGSVYSGGSPG ADRVIYD- QSGRFCACLTHTGAPSTNGFVECRF. It consisted of 101 amino acid residues, with a molecular weight of 10,760. RNase Po1 has relatively higher sequence homology with RNase T1 family RNase. It contains 6 half cystine residues. The locations of four of them are superimposable on those of RNase U1 and RNase U2. The amino acid residues forming the active site of RNase T1 were well conserved in this RNase. Therefore, RNase Po1 is a unique member of the RNase T1 family in respect of the location of one disulfide bridge, and its stability.


Assuntos
Guanosina Monofosfato/química , Polyporaceae/enzimologia , Ribonuclease T1/isolamento & purificação , Sequência de Aminoácidos , Aminoácidos/análise , Dados de Sequência Molecular , Filogenia , Ribonuclease T1/química , Homologia de Sequência de Aminoácidos , Relação Estrutura-Atividade , Especificidade por Substrato
11.
J Biochem ; 108(2): 303-10, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2229029

RESUMO

The complete primary structure of a base non-specific and adenylic acid preferential RNase (RNase M) from Aspergillus saitoi was determined. The sequence was determined by analysis of the peptides generated by digestion of heat-denatured RNase M with lysylendopeptidase, and the peptides generated from RCM RNase M by digestion with staphylococcal V8 protease or chemical cleavage with BrCN. It consisted of 238 amino acid residues and carbohydrate moiety attached to the 74th asparagine residue. The molecular weight of the protein moiety deduced from the sequence was 26,596. The locations of 10 half cystine residues are almost superimposable on those of RNase Rh from Rhizopus niveus and RNase T2 from Aspergillus oryzae which have similar base specificity. The homology between RNase M and RNase Rh and RNase T2 amounted to 97 and 160 amino acid residues, respectively. The amino acid sequences conserved in the three RNases are concentrated around the three histidine residues, which are supposed to form part of the active sites of these RNases.


Assuntos
Monofosfato de Adenosina/metabolismo , Aspergillus/enzimologia , Ribonucleases/análise , Sequência de Aminoácidos , Aminoácidos/análise , Fenômenos Químicos , Físico-Química , Cromatografia Líquida de Alta Pressão , Brometo de Cianogênio , Endopeptidases , Indicadores e Reagentes , Dados de Sequência Molecular , Peptídeos/análise , Desnaturação Proteica , Ribonucleases/química , Especificidade da Espécie , Terminologia como Assunto , Triptofano/análise
12.
J Biochem ; 124(4): 848-56, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9756633

RESUMO

A base non-specific and acid RNase was isolated from cellular slime mold (Dictyostelium discoideum) cells in a homogeneous state (about 2.4 kDa) by SDS-polyacrylamide gel electrophoresis. The RNase (RNase DdI) has a pH optimum of 5.0. The amino acid sequence of RNase DdI was determined by a combination of protein chemistry, a search of Data base, Dicty cDB and further sequence analysis of cDNA from the same bank. RNase DdI consists of 198 amino acid residues, and about 13.3, 0.9, 1.2, 3.3, and 1.0 residues of mannose, xylose, glucose, GlcNAc, and GalNAc, respectively. RNase DdI has two characteristic conserved segments of the RNase T2 family, and thus belongs to the RNase T2 family. Considering the fact that most of the RNase activity of D. discoideum is present in the lysosomal fraction [Wiener and Ashworth (1970) Biochem. J. 118, 505-512], it was concluded that the lysosomal RNase in D. discoideum is a member of the RNase T2 family. The amino acid sequence of RNase DdI is highly homologous with that of Physarum polycephalum RNase (RNase Phyb), and its amino acid sequence seems to be similar to those of plant/animal type RNases, rather than fungal RNases. The location of RNase DdI in the phylogenetic tree of the RNase T2 family was estimated.


Assuntos
Dictyostelium/enzimologia , Endorribonucleases/metabolismo , RNA/genética , RNA/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Cátions Bivalentes/farmacologia , Cromatografia de Afinidade , Cromatografia em Gel , Cromatografia por Troca Iônica , Códon , DNA Complementar/química , Dictyostelium/genética , Endorribonucleases/química , Endorribonucleases/isolamento & purificação , Evolução Molecular , Hexosaminas/análise , Cinética , Dados de Sequência Molecular , Filogenia , Plantas/enzimologia , RNA/química , RNA/isolamento & purificação , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
13.
J Neurol Sci ; 130(2): 146-53, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8586978

RESUMO

The clinical, genetic, and neuroradiologic characteristics of dentatorubral-pallidoluysian atrophy (DRPLA) are delineated in six patients from three generations of a Japanese family. The clinical characteristics of the disease varied, the age at onset depending on patients with juvenile-onset were characterized by myoclonus, epilepsy, and mental retardation whereas cerebellar ataxia, choreoathetosis, and dementia were typical of adult- and senile-onset patients. All affected individuals showed one expanded allele with the repeat number of CAG at the DRPLA locus, ranging from 58 to 82, and a normal allele, ranging from 10 to 21. The most severely affected patient, a case of maternal transmission and with the largest allele, became bedridden in a vegetative state by age 12. On the CT and MRI, varying degrees of brain atrophy were present in all patients. T2-weighted MRI in patients with senile-onset showed symmetric high-signal lesions in the cerebral white matter, globus pallidus, thalamus, midbrain, and pons. However, MRI in younger patients revealed no such lesions and CT failed to demonstrate lesions in the globus pallidus and brain stem. Thus, intrafamilial heterogeneity of DRPLA was also evident on MRI. High-signal lesions involving both, subcortical white matter and thalamus may be characteristics of senile-onset patients and may correlate with their dementia.


Assuntos
Globo Pálido/patologia , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/patologia , Núcleo Rubro/patologia , Adulto , Idoso , Alelos , Atrofia/genética , Atrofia/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Criança , DNA/metabolismo , Feminino , Humanos , Lactente , Japão , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/diagnóstico por imagem , Linhagem , Reação em Cadeia da Polimerase , Tomografia Computadorizada por Raios X
14.
J Chromatogr A ; 724(1-2): 179-84, 1996 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-8819795

RESUMO

The present studies have been conducted to investigate the cause of an unusually broad peak of ovalbumin obtained by countercurrent chromatography (CCC) reported earlier [K. Shinomija et al., J. Chromatogr., 644 (1993) 215]. A series of CCC experiments using our prototyte of the cross-axis coil planet centrifuge revealed that commercial ovalbumin products were classified into two groups: group A formed two peaks of ovalbumin at pH 7.0 and 5.8, while group B showed a relatively sharp single peak in a broad range of pH. Electrophoresis indicated that the group A ovalbumin consisted of both natural and denatured products: the natural ovalbumin is a monomer (Mr 45 000) whereas the denatured products form dimers (Mr 90 000). The abnormally broad peak obtained from the group A ovalbumin at pH 9 is apparently caused by the heterogeneity of the sample protein.


Assuntos
Cromatografia Líquida/métodos , Ovalbumina/química , Animais , Embrião de Galinha , Distribuição Contracorrente , Clara de Ovo , Eletroforese em Gel de Poliacrilamida
15.
Curr Eye Res ; 23(5): 368-71, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11910526

RESUMO

The levels of IGF-I in the vitreous body and the intraocular fluid of patients with proliferative diabetic retinopathy (PDR) were determined using radioimmunoassay (RIA). Eleven vitreous specimens were obtained from the intraocular fluid of eyes of patients with PDR who underwent surgery during the operation. Eleven intraocular fluids from the same patients during reoperations were compared with controls. The expression of IGF-I mRNA in cultured human Muller glial cells was evaluated using reverse transcription-polymerase chain reaction (RT-PCR). The mean IGF-I level in the vitreous samples during initial PDR surgery and reoperation was significantly higher than that found in the vitreous of the control (p < 0.05). The level of IGF-I increased in 6 of the 11 cases. Cultured human Muller cells expressed IGF-I mRNA. The results indicate increased levels of IGF-I both in the initial vitreous and ocular fluid at post-operative re-proliferation. Muller cell is suggested as an origin of local IGF-I production.


Assuntos
Retinopatia Diabética/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Corpo Vítreo/metabolismo , Adulto , Idoso , Células Cultivadas , Retinopatia Diabética/cirurgia , Feminino , Expressão Gênica , Humanos , Fator de Crescimento Insulin-Like I/genética , Masculino , Pessoa de Meia-Idade , Neuroglia/metabolismo , RNA Mensageiro/metabolismo , Radioimunoensaio , Reoperação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vitrectomia
16.
Intern Med ; 33(2): 123-6, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7912571

RESUMO

We describe a familial occurrence of primary hyperparathyroidism. The proband is a 60-year-old woman who had a parathyroid adenoma. Her older sister had a parathyroid adenoma with cementifying jaw fibroma and her younger sister died of parathyroid adenocarcinoma with pulmonary metastasis at the age of 38. We have not yet obtained evidence for other endocrine disorders suggesting multiple endocrine neoplasia (MEN) in this pedigree. The proband is complicated with Wilms' tumor. It is now widely accepted that respective predisposed genes of MEN type 1 and Wilms' tumor, and PTH gene are located on chromosome 11. The manifestation observed in this case may be related to mutational abnormalities on chromosome 11.


Assuntos
Adenocarcinoma/genética , Adenoma/genética , Hiperparatireoidismo/etiologia , Neoplasias Renais/genética , Segunda Neoplasia Primária/genética , Síndromes Neoplásicas Hereditárias/genética , Neoplasias das Paratireoides/genética , Tumor de Wilms/genética , Adenoma/complicações , Feminino , Humanos , Hipercalcemia/etiologia , Neoplasias Maxilomandibulares/genética , Leiomioma , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Neoplasia Endócrina Múltipla/genética , Síndromes Neoplásicas Hereditárias/classificação , Tumores Odontogênicos/genética , Neoplasias das Paratireoides/complicações , Linhagem , Neoplasias Uterinas , Tumor de Wilms/secundário
17.
Ind Health ; 31(4): 143-53, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7512540

RESUMO

Intratracheal instillation of GaAs suspension has been histopathologically shown to induce a diffuse pulmonary response. In the present study, magnetometry was used to evaluate the effects of intratracheally instilled GaAs on the behavior of externally magnetized iron particles instilled in rabbit lung. Magnetometric evaluation of the effects of GaAs in rabbits dosed with 30 mg or 300 mg/animal showed significant decreased relaxation of iron particles at 1, 3, 7, 14, 21 and 28 days following instillation compared with the controls. Relaxation indicates a rapid decrease of remanent magnetic field following magnetization of the lungs due to random rotation of phagocytized iron particles in macrophages. Clearance of the iron particles was measured by serial determinations of the remanent magnetic field at the end of magnetization estimated from relaxation curves. Clearance was significantly impaired in rabbits exposed to both doses of GaAs at 14, 21 and 28 days after instillation. Dose-effect relationships were observed in both cases. Histological examination of lungs instilled with these doses indicated active phagocytosis of GaAs and iron particles by alveolar macrophages.


Assuntos
Arsenicais/farmacologia , Gálio/farmacologia , Ferro/farmacocinética , Pulmão/efeitos dos fármacos , Magnetismo , Animais , Relação Dose-Resposta a Droga , Campos Eletromagnéticos , Compostos Férricos/administração & dosagem , Pulmão/patologia , Macrófagos Alveolares/ultraestrutura , Coelhos
18.
Artigo em Inglês | MEDLINE | ID: mdl-9886109

RESUMO

In an attempt to investigate possible urban-rural difference in prevalence of hepatitis B and C virus (HBV and HCV, respectively) infection in continental China, triplet surveys on HBV and HCV infection markers (ie, HBsAg, anti-HBs, anti-HBc, and anti-HCV) and serum enzyme levels (AST, ALT and gamma-GTP) were conducted in 1997 on groups of apparently healthy adult women (49 to 50 subjects per group); one group (the City group) was in Xian, the provincial capital of Shaanxi Province, and two others (the Village A group and the Village B group) were in farming villages in the Province some 200 and 25 km away from Xian, respectively. Comparison among the three groups showed that there was no urban-rural difference in prevalence of HBV and HCV infection positive (HBV+ and HCV+) cases and that the overall prevalence of HBV+ and HCV+ cases was 70% and 3%, respectively. HBsAg+ prevalence was however higher in the villages (8% when the two villages were combined) than in the city (2%). HBV infection was not associated in general with apparent increase in emission enzyme levels in the serum, whereas HCV infection might be associated with an increase in ALT, AST and gamma-GTP. The present observation in combination with other previously published results suggests that urban-rural difference will not be remarkable in HBV and HCV infection prevalence in Continental China and that the public health problem is more serious with HBV infection and quite less so with HCV infection.


Assuntos
Hepatite B/epidemiologia , Hepatite C/epidemiologia , Saúde da População Rural , Saúde da População Urbana , Saúde da Mulher , Adulto , Idoso , Anticorpos Antivirais/sangue , Biomarcadores/sangue , China/epidemiologia , Feminino , Hepatite B/sangue , Hepatite C/sangue , Humanos , Pessoa de Meia-Idade , Prevalência
19.
Ophthalmic Surg Lasers ; 30(3): 229-31, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10100261

RESUMO

We report a case of an 8-year-old boy who presented with an intraocular foreign body composed of graphite pencil lead. The patient had been accidentally poked in the right eye with a graphite pencil. Primary care consisted of corneal suturing and lens extraction. Two pieces of the pencil lead remained in the vitreous cavity following surgery, and 2 days later the patient developed endophthalmitis. Pars plana vitrectomy was performed immediately and the intraocular foreign bodies were removed through the scleral wound. Cultures of the vitreous fluid revealed no bacterial organisms. X-ray fluoroscopic analysis of the vitreous detected 1 ppm of aluminum (a constituent of the pencil lead). Although the clinical presentation indicated probable bacterial endophthalmitis, the detection of elemental aluminum within the vitreous cavity also suggested the possibility of further retinal toxicity due to some dissolving of the pencil lead.


Assuntos
Lesões da Córnea , Endoftalmite/etiologia , Corpos Estranhos no Olho/complicações , Infecções Oculares Bacterianas/etiologia , Ferimentos Oculares Penetrantes/complicações , Catarata/etiologia , Extração de Catarata , Criança , Endoftalmite/diagnóstico , Endoftalmite/cirurgia , Corpos Estranhos no Olho/diagnóstico , Corpos Estranhos no Olho/cirurgia , Infecções Oculares Bacterianas/diagnóstico , Infecções Oculares Bacterianas/cirurgia , Ferimentos Oculares Penetrantes/diagnóstico , Ferimentos Oculares Penetrantes/cirurgia , Seguimentos , Humanos , Fotocoagulação a Laser , Cristalino/lesões , Cristalino/cirurgia , Masculino , Reoperação , Ruptura , Tomografia Computadorizada por Raios X , Vitrectomia
20.
No To Hattatsu ; 22(1): 61-5, 1990 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-2294952

RESUMO

Two siblings with interstitial deletion of chromosome 14 not associated with ring formation were reported. Clinical features of the patients included failure to thrive, severe mental retardation, microcephaly, round face, hypertelorism, micrognathia and high-arched palate. They were common also in five previously reported cases. Other peculiar finding was hyperthyrotropinemia in their neonatal periods; mild hypothyroidism was found in the elder sister, and hyperthyrotropinemia was only transient in the younger sister. By a high-resolution G-banding analysis, the maternal origin of the chromosome with the deletion was noted.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 14 , Anormalidades Múltiplas/sangue , Anormalidades Múltiplas/genética , Pré-Escolar , Feminino , Humanos , Lactente , Deficiência Intelectual/sangue , Deficiência Intelectual/genética , Cariotipagem , Tireotropina/sangue
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