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1.
Int J Lab Hematol ; 33(5): 526-32, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21463487

RESUMO

INTRODUCTION: T-helper cell type 1 (Th1) polarization of the immune response has been documented in patients with chronic immune thrombocytopenia (ITP). Interleukin (IL)-10 is the most important factor regulating Th1 and T-helper type 2 cytokine synthesis. This study evaluated the impact of IL-10 polymorphisms on both susceptibility to, and severity of, chronic ITP. METHODS: We analyzed -1082(G/A), -812(C/T), and -592(C/A) IL-10 polymorphisms in 90 patients with adult chronic ITP and 202 race- and sex-matched healthy controls. RESULTS: No significant differences in the genotype or haplotype frequencies were observed between the patient with chronic ITP and the control group. However, more patients with the -592AA genotype showed a severe thrombocytopenic state (platelet count <10 x 109/l) than those with the -592CC/CA genotypes (44.1%vs. 19.6%, P = 0.01). Furthermore, more patients with the ATA/ATA haplotype showed a severe thrombocytopenic state than those without the ATA/ATA haplotype (44.1%vs. 19.6%, P = 0.01). CONCLUSION: According to our data, patients with low producer type of IL-10 polymorphisms have more severe thrombocytopenia, suggesting that IL-10 gene polymorphisms may reflect the severity of ITP.


Assuntos
Interleucina-10/genética , Polimorfismo de Nucleotídeo Único/genética , Púrpura Trombocitopênica Idiopática/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Povo Asiático/genética , Doença Crônica , Feminino , Frequência do Gene , Genótipo , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , Púrpura Trombocitopênica Idiopática/terapia , Resultado do Tratamento , Adulto Jovem
2.
Int J Lab Hematol ; 31(6): 630-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18691343

RESUMO

In this study, we attempted to evaluate the clinical significance of T helper 1 (Th1)/T helper 2 (Th2) ratio in patients with myelodysplastic syndrome (MDS), five refractory anaemia (RA), four refractory anaemia with ringed sideroblasts (RARS), 31 refractory cytopenia with multilineage dysplasia (RCMD), nine refractory anaemia with excess blast-1 (RAEB-1) and seven refractory anaemia with excess blast-2 (RAEB-2). Intracellular interleukin-4 (Th2 cytokine) and interferon-gamma (Th1 cytokine) production was assessed in CD4+ T lymphocytes activated by phorbol 12-myristate 13-acetate and ionomycin using flow cytometry. Mean Th1/Th2 ratios in each MDS group were as follows: RA/RARS, 8.8 (95% CI, 5.8-11.8), RCMD, 14.7 (95% CI, 9.5-19.9), RAEB-1, 10.6 (95% CI, 4.6-16.6), RAEB-2, 12.8 (95% CI, 3.0-22.7) and control 12.8 (95% CI, 9.6-16.1). There were no significant differences in Th1/Th2 ratio in the RA/RARS, RCMD, RAEB-1 and RAEB-2 subgroups when compared to controls. Because Th1/Th2 ratio in the RCMD group was widely distributed, we divided RCMD patients according to Th1/Th2 ratio into three groups (low, normal and high Th1/Th2 groups). There were no differences in severity of cytopenia among the three above groups. However, the percentage of CD8 cells in the low Th1/Th2 group was significantly lower than those in the high group (P < 0.01). These data suggest that Th1/Th2 imbalance induces CD4/CD8 imbalance, and serves as a marker of the biological interplay in immune regulation.


Assuntos
Síndromes Mielodisplásicas/imunologia , Células Th1/imunologia , Células Th2/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia Refratária/imunologia , Anemia Sideroblástica/imunologia , Relação CD4-CD8 , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Feminino , Humanos , Interferon gama , Interleucina-4/biossíntese , Masculino , Pessoa de Meia-Idade
3.
Ann Hematol ; 80(8): 452-5, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11563589

RESUMO

The survival time of myeloma patients improved from a few months to many years after treatment with melphalan. Perhaps chemotherapy more intensive than melphalan-prednisolone should be administered to patients at risk of early death. Therefore, early death must be accurately predicted. We analyzed 93 patients with recently diagnosed myeloma and found that 13 (14%) died within 6 months (early death). The most common cause of death was bacterial and fungal pneumonia when myeloma became uncontrollable. The response to conventional chemotherapy was poorer in patients at high risk of early death than the control group. Multivariate analysis showed that the serum level of beta-2 microglobulin was the only value that predicted early death.


Assuntos
Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/terapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/sangue , Análise Multivariada , Prognóstico , Fatores de Risco , Fatores de Tempo , Microglobulina beta-2/sangue
4.
Yakugaku Zasshi ; 121(3): 193-213, 2001 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-11265115

RESUMO

The following topics are described: 1. chemistry of beta-lactamases; 2. beta-lactamases from Streptomyces including distribution of beta-lactamases in actinobacteria, properties of beta-lactamases from Streptomyces, cloning and regulatory mechanism of expression of beta-lactamase genes from Streptomyces and evolution and classification of beta-lactamases in general; 3. penicillin-binding proteins from Streptomyces including beta-lactam-producing- and non-producing strains and 4. eukaryotic-type protein kinases from Streptomyces including cloning of the genes and evolution and classification of eukaryotic-type protein kinases in general.


Assuntos
Antibacterianos/biossíntese , Proteínas de Bactérias , Resistência Microbiana a Medicamentos , Hexosiltransferases , Peptidil Transferases , Streptomyces , beta-Lactamases , Sequência de Aminoácidos , Proteínas de Transporte , Clonagem Molecular , Evolução Molecular , Regulação Enzimológica da Expressão Gênica , Dados de Sequência Molecular , Muramilpentapeptídeo Carboxipeptidase , Proteínas de Ligação às Penicilinas , Pró-Fármacos , Proteínas Quinases/química , Proteínas Quinases/genética , Streptomyces/enzimologia , Streptomyces/metabolismo , beta-Lactamases/classificação , beta-Lactamases/genética , beta-Lactamas
5.
Bioorg Med Chem ; 9(2): 477-86, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11249139

RESUMO

To develop a potent and effective anti-HIV compound with a definite polyanionic structure, synthesis of oligotyrosine sulfates by oligomerization with simultaneous sulfation of tyrosine was tried. One component was successfully isolated from the mixture containing many products as its sodium salt (Y-ART-4) and was identified as the salt of nonatyrosine N- and O1-9-decasulfate, NaO3S-[Tyr(SO3Na)]9-ONa. Anti-HIV activity of Y-ART-4, determined from the protection it provided against HIV-induced cytopathic effects, was almost the same with that of dextran sulfate and curdlan sulfate.


Assuntos
Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/farmacologia , Linhagem Celular Transformada/efeitos dos fármacos , Linhagem Celular Transformada/microbiologia , Cromatografia Líquida de Alta Pressão , Efeito Citopatogênico Viral , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Humanos , Concentração Inibidora 50 , Oligopeptídeos , Fosfotransferases/antagonistas & inibidores , DNA Polimerase Dirigida por RNA/metabolismo , Inibidores da Transcriptase Reversa/síntese química , Inibidores da Transcriptase Reversa/farmacologia , Tirosina/análogos & derivados
6.
Bioorg Med Chem ; 9(2): 487-92, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11249140

RESUMO

Fully N- and O-sulfated homooligomers from octamer to nonadecamer of tyrosine were obtained as their sodium salts, aO3S-[Tyr(SO3Na)]n-ONa (n = 8-19), from reaction mixtures of tyrosine with sulfur trioxide trimethylamine and pyridine comlexes, respectively, in pyridine. Their anti-HIV activity increased along with the increase of the chain length up to the dodecamer, maintained the same level to the length of the heptadecamer and then decreased. The maximal activity level was the same as or higher than that of dextran and curdlan sulfates.


Assuntos
Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/farmacologia , Linhagem Celular Transformada/efeitos dos fármacos , Linhagem Celular Transformada/microbiologia , Cromatografia Líquida de Alta Pressão , Técnicas de Química Combinatória , Efeito Citopatogênico Viral , Humanos , Concentração Inibidora 50 , Oligopeptídeos , Relação Estrutura-Atividade , Tirosina/análogos & derivados
7.
Antimicrob Agents Chemother ; 43(12): 3014-7, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10582901

RESUMO

The distribution of beta-lactamase activities in a collection of actinomycete strains was surveyed. Six of 127 strains were found to produce beta-lactamase. This low frequency was in contrast to the case with Streptomyces species. The producing strains were not related phylogenetically. MICs of benzylpenicillin did not correlate with beta-lactamase production.


Assuntos
Actinomycetales/enzimologia , beta-Lactamases/metabolismo , Actinomycetales/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Penicilina G/farmacologia , Resistência às Penicilinas , Penicilinas/farmacologia , Filogenia , Fatores de Tempo
8.
Eur J Haematol ; 62(1): 63-7, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9918314

RESUMO

The morphology of myeloma cells is reported to be one of the prognostic factors in multiple myeloma (MM) patients. We analyzed the prognostic factors, including morphological classification, in 292 patients with MM in order to select poor-risk patients who should be considered candidates for early intensive chemotherapy, including stem cell transplantation. Multivariate analysis was applied to 90 patients diagnosed between 1989 and 1996, because serum beta-2-microglobulin (beta2M) has been measured regularly since 1989, and showed that serum albumin, serum beta2M, and the morphology of myeloma cells predicted survival. According to these factors, patients were divided into 3 risk groups; a high-risk group (14%), a intermediate-risk group (46%) and a low-risk group (40%). There were significant differences between survival times in these 3 groups (median survival: high-risk, 16; intermediate-risk, 22; and low-risk, 44 months).


Assuntos
Mieloma Múltiplo/diagnóstico , Estadiamento de Neoplasias/métodos , Plasmócitos/patologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/epidemiologia , Mieloma Múltiplo/mortalidade , Análise Multivariada , Prognóstico , Fatores de Risco , Taxa de Sobrevida
9.
J Med ; 28(5-6): 311-8, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9604789

RESUMO

In ten patients with multiple myeloma (MM), serum beta-2-microglobulin (B2M) levels were monitored in order to clarify the influence of alpha interferon (IFN) administration. Despite decreases in M-protein and the absence of renal dysfunction, the levels of serum B2M were sustained above those prior to melphalan-prednisolone and IFN therapy in seven patients with MM for six months. Serum B2M did not increase in ten patients with MM treated only by melphalan-prednisolone. Furthermore, serum B2M levels in a patient who achieved a complete response were sustained above her prior level and returned to normal after cession of IFN therapy. Our study suggests that the serum B2M level is increased by treatment with IFN, and does not prove the condition of the disease.


Assuntos
Antineoplásicos/uso terapêutico , Interferon-alfa/uso terapêutico , Mieloma Múltiplo/sangue , Mieloma Múltiplo/terapia , Microglobulina beta-2/análise , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Pré-Escolar , Esquema de Medicação , Feminino , Humanos , Lactente , Interferon-alfa/administração & dosagem , Masculino , Melfalan/administração & dosagem , Pessoa de Meia-Idade , Prednisolona/administração & dosagem
10.
Antiviral Res ; 30(2-3): 95-108, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8783802

RESUMO

To evaluate the efficacy of Y-ART-3 as an antiviral drug for HIV infections, its anti-HIV activity was assessed in vitro in cell culture systems and in vivo in hu-PBL-SCID mice. The results indicated that Y-ART-3 invariably inhibited not only HIV-1, but also HIV-2 and SIV strains. Its mechanism of action is ascribed to inhibition of viral adsorption to CD4-positive cells. In an in vivo study, human Ig- and CD4-positive cells were detected at similar levels in Y-ART-3-treated hu-PBL-SCID mice that were infected with HIV, and in PBS-treated control hu-PBL SCID mice that were not infected with HIV. If HIV positivity was calculated using the number of tests in which HIV was detected (i.e. PCR, and p24 from co-cultures of spleen and peritoneal wash cells), a significant effect of Y-ART-3 at a dose of 4 mg/kg was noted. Therefore, Y-ART-3 may be considered to be a potent and effective anti-HIV compound.


Assuntos
Antivirais/farmacologia , Ácido Gálico/análogos & derivados , Glucose/análogos & derivados , HIV-1/efeitos dos fármacos , HIV-2/efeitos dos fármacos , Taninos Hidrolisáveis , Vírus da Imunodeficiência Símia/efeitos dos fármacos , Taninos/farmacologia , Animais , Antivirais/imunologia , Linhagem Celular , Efeito Citopatogênico Viral , Ácido Gálico/química , Ácido Gálico/farmacologia , Células Gigantes , Glucose/química , Glucose/farmacologia , Proteína do Núcleo p24 do HIV/metabolismo , HIV-1/metabolismo , HIV-1/fisiologia , HIV-2/fisiologia , Humanos , Camundongos , Camundongos SCID , Vírus da Imunodeficiência Símia/fisiologia , Taninos/imunologia , Células Tumorais Cultivadas , Replicação Viral
11.
J Antibiot (Tokyo) ; 48(10): 1076-80, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7490210

RESUMO

The effects of cochlioquinone A, isolated from Drechslera sacchari, were studied in vitro and in vivo. This compound specifically inhibited diacylglycerol kinase activity with Ki = 3.1 microM. The kinetics revealed that cochlioquinone A inhibited diacylglycerol kinase in competition with ATP, and non-competitively with diacylglycerol. The compound inhibited neither protein kinase C, epidermal growth factor receptor-associated protein tyrosine kinase, nor phospholipase C. Cochlioquinone A reduced the concentration of phosphatidic acid in T cell lymphoma with a half maximal concentration of 3 microM, and simultaneously augmented the phosphorylation of 80 kDa protein, a known substrate of protein kinase C. The degree of the phosphorylation of 80 kDa protein in the presence of cochlioquinone A was similar to that in the presence of phorbol myristate acetate (0.1 microgram/ml). These results demonstrate that cochlioquinone A is a specific inhibitor of diacylglycerol kinase, which regulates the activity of protein kinase C.


Assuntos
Antinematódeos/farmacologia , Benzoquinonas/farmacologia , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Animais , Antinematódeos/farmacocinética , Benzoquinonas/farmacocinética , Bovinos , Células Cultivadas , Diacilglicerol Quinase
12.
J Bacteriol ; 177(18): 5342-5, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7545157

RESUMO

A gene was cloned from Streptomyces coelicolor A3(2). It encodes a protein of 368 amino acid residues with a high degree of similarity to prokaryotic release factor 2. However, it has neither an internal stop codon nor the Shine-Dalgarno-like sequence immediately upstream of the assumed frameshift position. The gene is expressed and functional in Escherichia coli as peptide chain release factor 2. The transcription start site is at or adjacent to the translational start site. The size of the mRNA detected by hybridization suggests that the gene (prfB) is monocistronic in S. coelicolor A3(2). However, about 80 bp upstream of the gene there is an operon which is composed of two genes encoding eukaryotic-type serine/threonine kinases.


Assuntos
Sequência Conservada/genética , Genes Bacterianos/genética , Fatores de Terminação de Peptídeos/genética , Biossíntese de Proteínas/genética , Streptomyces/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Códon de Terminação , Escherichia coli/genética , Dados de Sequência Molecular , Óperon/genética , Fatores de Terminação de Peptídeos/química , Proteínas Serina-Treonina Quinases/genética , RNA Bacteriano/biossíntese , RNA Mensageiro/biossíntese , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Streptomyces/química , Transcrição Gênica/genética
13.
Gene ; 153(1): 99-104, 1995 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-7883195

RESUMO

A 6.3-kb DNA fragment encoding two eukaryotic-type serine/threonine protein kinases (Ser/Thr PK) was cloned from Streptomyces coelicolor A3(2) by using a PCR product obtained with primers based on highly conserved regions of eukaryotic Ser/Thr PK. The nucleotide (nt) sequence of the essential 4.4-kb fragment contained two possible ORFs. One ORF (PkaA) contained 543 amino acids (aa), while another (PkaB) consisted of 417 aa. The N-terminal half of both proteins showed significant similarity with the catalytic domain of eukaryotic Ser/Thr PK. On the other hand, the C-terminal region of PkaA, but not of PkaB, is rich in Pro and Gln residues, indicating that PkaA works as a PK as well as a transcription factor. The pkaB gene was overexpressed in Escherichia coli, and the gene product (PkaB) was found to be phosphorylated mainly at Thr. The pkaA gene was also overexpressed in E. coli, and the gene product (PkaA) was found to be phosphorylated mainly at Thr and slightly at Ser. In the case of PkaA, at least 100 aa residues from the C terminus were not essential for the PK activity. When the PCR product was used as a probe, it hybridized to DNA fragments from all the Streptomyces species tested, indicating that these types of Ser/Thr PK are distributed ubiquitously and play significant physiological roles in the various species of Streptomyces.


Assuntos
Proteínas de Bactérias/genética , Genes Bacterianos , Proteínas Serina-Treonina Quinases/genética , Streptomyces/genética , Fatores de Transcrição , Sequência de Aminoácidos , Animais , Proteínas de Bactérias/biossíntese , Sequência de Bases , Clonagem Molecular , Escherichia coli/genética , Células Eucarióticas/enzimologia , Humanos , Camundongos , Dados de Sequência Molecular , Fases de Leitura Aberta , Fosforilação , Processamento de Proteína Pós-Traducional , Proteínas Serina-Treonina Quinases/biossíntese , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Streptomyces/enzimologia
14.
Antimicrob Agents Chemother ; 39(1): 260-3, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7535038

RESUMO

The beta-lactamase gene from Streptomyces fradiae Y59 was cloned and sequenced. To determine which amino acid residues are critical in binding activity to blue dextran, chimera beta-lactamases were constructed and their binding abilities were determined. The results suggested that blue dextran binding may depend more on overall conformation of about two-thirds of the beta-lactamase molecule from the N terminus than on the primary structure.


Assuntos
Streptomyces/genética , beta-Lactamases/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Dextranos/metabolismo , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , beta-Lactamases/metabolismo
16.
Biochim Biophys Acta ; 1221(1): 29-35, 1994 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-8130274

RESUMO

An isoflavone compound, daidzein, inhibits the cell proliferation of Swiss 3T3 cells. Analysis of entry in S phase of Swiss 3T3 cells reveals that daidzein blocked cell cycle G1 phase progression 4.6 h after stimulation by bombesin plus insulin. After removal of daidzein, insulin or insulin-like growth factors (IGFs) reinitiate cell cycle progression of daidzein-blocked cells without further addition of bombesin. The order in the mitogenic action of insulin or IGFs is as follows: IGF-1 (5 ng/ml) >> IGF-2 (0.5 microgram/ml) congruent to insulin (1 microgram/ml). Studies in vivo of protein kinase activation by mitogenic stimulation reveal that the treatment with daidzein decreased the activation of a MAP2 phosphorylating protein kinase (MAP2 kinase). In vitro kinase assays showed that daidzein inhibits casein kinase II activity, but does not inhibit MAP2 kinase activity. Activation of casein kinase II by polylysine augments the activity of MAP2 kinase in digitonin-permeabilized 3T3 cells. These results suggest that daidzein blocked G1 phase cell cycle progression of Swiss 3T3 by inhibiting the activity of casein kinase II which is required for the commitment of mitogenic signal by insulin or IGF-1 in G1 phase.


Assuntos
Ciclo Celular/fisiologia , Estrogênios não Esteroides/farmacologia , Antagonistas da Insulina/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Insulina/farmacologia , Isoflavonas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Células 3T3 , Animais , Bombesina/farmacologia , Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Caseína Quinases , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Humanos , Fator de Crescimento Insulin-Like I/antagonistas & inibidores , Fator de Crescimento Insulin-Like II/farmacologia , Cinética , Camundongos , Fator de Crescimento Derivado de Plaquetas/farmacologia , Inibidores de Proteínas Quinases , Proteínas Quinases/metabolismo , Proteínas Recombinantes/farmacologia , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Fatores de Tempo
17.
FEMS Microbiol Lett ; 112(3): 343-8, 1993 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-8224800

RESUMO

A hybridized DNA fragment was cloned as a 7.6-kb fragment from Streptomyces lavendulae KCCS0263 using a 1.9-kb SacI-XbaI DNA fragment from S. cellulosae as a probe. The latter fragment encoded a beta-lactamase which can bind blue dextran. The hybridized region was reduced to a 2.8-kb KpnI-BclI fragment and the nucleotide sequence was determined. The nucleotide sequence indicated one open reading frame whose amino acid sequence is very similar to that of the beta-lactamase from S. cellulosae. The gene produced beta-lactamase enzyme at a low but significant amount.


Assuntos
Genes Bacterianos , Streptomyces/genética , beta-Lactamases/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Expressão Gênica , Dados de Sequência Molecular , Filogenia , Mapeamento por Restrição , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Streptomyces/classificação
18.
Mol Phylogenet Evol ; 2(2): 97-111, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8025724

RESUMO

beta-Lactamases are the main cause of beta-lactam resistance in many pathogenic bacteria. These enzymes can be detected in a variety of pathogenic as well as non-pathogenic bacteria. The cyanobacteria are also known to produce a beta-lactamase. Recently, the amino acid sequences and the three-dimensional structures of some of these beta-lactamases have been clarified. On the basis of the amino acid sequences of 47 beta-lactamases and the computer-aided analysis, a phylogenetic tree is proposed in this paper. According to the tree, beta-lactamases are classified into six groups. Group 1 beta-lactamases are mainly composed of plasmid-mediated enzymes from gram-negative bacteria. However, chromosome-derived beta-lactamases from Klebsiella pneumoniae and Rhodopseudomonas capsulata take part in this group. Group 2 enzymes consist of a part of the chromosome-encoded beta-lactamases from Streptomyces, and chromosome-mediated enzymes from Yersinia enterocolitica, Citrobacter diversus, and Klebsiella oxytoca. Chromosome-encoded beta-lactamases from gram-negative bacteria form group 3. Group 4 is composed of metalloenzymes, whereas group 5 consists of OXA type beta-lactamases. Chromosome-encoded beta-lactamases from gram-positive bacteria form group 6. Comparison of the amino acid sequences among these groups confirmed the phylogenetic tree and the classification: the beta-lactamases in each group have its particular conserved amino acid sequences. In addition, the tree provides more detailed classification and time-scale mutual relationships and predicts new types of beta-lactamases that may be found. Furthermore, the classification deduced from the tree is generally in accord with the one based on the amino acid sequences reported previously. However, the class A beta-lactamases are clearly divided into three groups: groups 1, 2, and 6. RDF2 analysis shows that some combinations between beta-lactamases and beta-lactam-interacting proteins as well as eukaryotic proteins have a low but significant evolutionary relatedness.


Assuntos
Bactérias/genética , Filogenia , beta-Lactamases/genética , Sequência de Aminoácidos , Bactérias/classificação , Bactérias/enzimologia , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , beta-Lactamases/classificação
19.
Rinsho Ketsueki ; 34(4): 444-9, 1993 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-8510331

RESUMO

Quantitation of peripheral circulating myeloma cell precursors, problems on serum beta 2-microglobulin value which is a prognostic factor in myeloma, and prognostic factors associated with long-term survival in our Japanese myeloma patients are described. Peripheral blood mononuclear cells were cultured in vitro in the presence of various recombinant cytokines and differentiated to plasma cells to quantify peripheral circulating myeloma cell precursors. It has speculated that the variation in the number of myeloma cell precursors in peripheral blood could be used as a parameter of the efficacy of chemotherapy in patients with myeloma. Serum beta 2-microglobulin value increased with age and under alpha-interferon therapy in myeloma, even if M protein decreased, suggesting that its value should be carefully monitored when evaluating the response to alpha-interferon and other chemotherapeutic agents. Of 1,119 Japanese patients with symptomatic myeloma who were newly diagnosed at 16 institutions of the Japan Myeloma Study Group between 1965 and 1981, 38 (3.4%) patients survived for more than 10 years. In comparison with 121 patients who died within 10 years in our institution, younger age, low and intermediate tumor mass, lower plasmacytosis, higher percentages of granulocytes and erythroblasts in bone marrow, and subtype classified as mature or intermediate were strongly correlated with long-term survival.


Assuntos
Mieloma Múltiplo/sangue , Adulto , Idoso , Feminino , Humanos , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia , Mieloma Múltiplo/terapia , Proteínas do Mieloma/metabolismo , Prognóstico , Taxa de Sobrevida , Microglobulina beta-2/metabolismo
20.
Gene ; 125(1): 91-6, 1993 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-8449418

RESUMO

The argG gene, encoding argininosuccinate synthetase, was cloned from Streptomyces lavendulae KCCS0055 by colony hybridization using the argG-carrying 2.1-kb fragment of S. coelicolor DNA as a probe. The restriction map of the cloned DNA fragment was very similar to that of S. coelicolor. This DNA fragment could complement the argG mutation of both S. lividans 1326 I10 and Escherichia coli K-12 JE5694, suggesting that the fragment contained a promoter for both E. coli and S. lividans. The subcloning experiment using E. coli K-12 JE5694 as a host has indicated that the essential region for argG is contained in the 2.5-kb DNA fragment. The translational product was identified as a 56-kDa kDa protein in minicells and by conventional gel electrophoresis. Determination of the nucleotide (nt) sequence of the 2.5-kb DNA fragment revealed one open reading frame of 1449 bp. The amino acid (aa) sequence analysis showed that the N-terminus was Ser, and 9 aa from the N terminus were completely identical with those deduced from the nt sequence. Nuclease S1 mapping indicated that the transcription start point is located near the start codon.


Assuntos
Argininossuccinato Sintase/genética , Streptomyces/enzimologia , Sequência de Aminoácidos , Argininossuccinato Sintase/biossíntese , Sequência de Bases , Clonagem Molecular , Escherichia coli , Expressão Gênica , Dados de Sequência Molecular , Biossíntese de Proteínas , Proteínas Recombinantes/biossíntese , Endonucleases Específicas para DNA e RNA de Cadeia Simples , Transcrição Gênica
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