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1.
Phys Rev Lett ; 109(15): 156602, 2012 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-23102348

RESUMO

We demonstrate that a giant spin Hall effect (SHE) can be induced by introducing a small amount of Bi impurities in Cu. Our analysis, based on a new three-dimensional finite element treatment of spin transport, shows that the sign of the SHE induced by the Bi impurities is negative and its spin Hall (SH) angle amounts to -0.24. Such a negative large SH angle in CuBi alloys can be explained by applying the resonant scattering model proposed by Fert and Levy [Phys. Rev. Lett. 106, 157208 (2011)] to 6p impurities.

2.
J Exp Med ; 166(4): 967-81, 1987 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-2821154

RESUMO

B cell stimulatory factor 2 receptors (BSF-2-R) were studied using radioiodinated recombinant BSF-2 with a specific activity of 6.16 X 10(13) cpm/g. Kinetic studies showed that binding of 125I-BSF-2 to CESS cells reached maximum level within 150 min at 0 degrees C. There was a single class of receptors with high affinity (Kd 3.4 X 10(-10) M) on CESS, and the number of receptors was 2,700 per cell. Binding of 125I-BSF-2 to CESS was competitively inhibited by unlabeled BSF-2 but not by IL-1, IL-2, IFN-beta, IFN-gamma, and G-CSF, indicating the presence of the receptors specific for BSF-2. EBV-transformed B lymphoblastoid cell lines (CESS, SKW6-CL4, LCL13, and LCL14) expressed BSF-2-R, whereas Burkitt's lines did not. EBV or EBNA2 did not induce the expression of the receptors on Burkitt's cells. The plasma cell lines (ARH-77 and U266) expressed BSF-2-R, fitting the function of BSF-2 as plasma cell growth factor. Several other cell lines, the histiocytic line U937, the promyelocytic line HL60, the astrocytoma line U373 and the glioblastoma line SK-MG-4, in which BSF-2 was inducible with IL-1 or TPA, displayed BSF-2-R with Kd in the range of 1.3-6.4 X 10(-10) M, suggesting the autocrine mechanism in BSF-2 function. The four T cell lines (CEM, HSB, Jurkat, and OM 1) did not express a detectable number of receptors, but normal resting T cells expressed 100-1,000 receptors per cell. BSF-2-R were not present on normal resting B cells but expressed on activated B cells with a Kd of 3.6-5.0 X 10(-10) M, fitting the function of BSF-2, which acts on B cells at the final maturation stage to induce immunoglobulin production.


Assuntos
Linfócitos B/fisiologia , Produtos Biológicos/metabolismo , Linfocinas/metabolismo , Receptores Mitogênicos/análise , Astrocitoma/análise , Ligação Competitiva , Linhagem Celular , Transformação Celular Viral , Citocinas , Glioma/análise , Herpesvirus Humano 4 , Histiocitoma Fibroso Benigno/análise , Humanos , Interleucina-6 , Radioisótopos do Iodo , Marcação por Isótopo , Cinética , Leucemia Mieloide Aguda/metabolismo , Receptores de Interleucina-4 , Receptores Mitogênicos/biossíntese , Proteínas Recombinantes/metabolismo , Distribuição Tecidual
3.
Science ; 241(4867): 825-8, 1988 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-3136546

RESUMO

Interleukin-6 (IL-6/BSF-2/IFN beta 2) is a multifunctional cytokine that regulates the growth and differentiation of various tissues, and is known particularly for its role in the immune response and acute phase reactions. A complementary DNA encoding the human IL-6 receptor (IL-6-R) has now been isolated. The IL-6-R consists of 468 amino acids, including a signal peptide of approximately 19 amino acids and a domain of approximately 90 amino acids that is similar to a domain in the immunoglobulin (Ig) superfamily. The cytoplasmic domain of approximately 82 amino acids lacks a tyrosine/kinase domain, unlike other growth factor receptors.


Assuntos
Clonagem Molecular , Genes , Transcrição Gênica , Sequência de Aminoácidos , Sequência de Bases , Linhagem Celular , DNA/genética , DNA/isolamento & purificação , Humanos , Cadeias kappa de Imunoglobulina/genética , Dados de Sequência Molecular , Receptores Imunológicos/genética , Receptores de Interleucina-6 , Homologia de Sequência do Ácido Nucleico
4.
Eur Neuropsychopharmacol ; 17(4): 273-6, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17116390

RESUMO

The CLOCK gene has attracted attention due to its influence on the circadian rhythm, as well as its impacts on the dopaminergic system. We conducted a preliminary study to examine whether the T3111C single nucleotide polymorphism of the CLOCK gene is associated with the development of schizophrenia by examining samples from schizophrenics (n=145) and normal controls (n=128). Both genotype and allele frequencies were significantly different between schizophrenics and controls (p=0.022, p=0.015, respectively). Schizophrenics had a significantly higher frequency of the C allele compared to controls (odds ratio 1.76, 95% CI 1.12-2.75). In particular, disorganized and residual type schizophrenics had significantly higher C allele frequencies than controls (p=0.004 and p=0.037, respectively). Our results suggest that the T3111C polymorphism of the CLOCK gene is associated with schizophrenia. It is important to explore the association between CLOCK and dopamine function, and to examine the impact of CLOCK on phenotypes such as symptoms and drug response in patients with schizophrenia.


Assuntos
Polimorfismo Genético/genética , Esquizofrenia/genética , Transativadores/genética , Adulto , Proteínas CLOCK , Análise Mutacional de DNA , Feminino , Frequência do Gene , Genótipo , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Estatísticas não Paramétricas
5.
Epidemiol Psychiatr Sci ; 25(1): 58-68, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25373686

RESUMO

BACKGROUND: Little is known about whether particular suicide methods have contributed differently to the recent unfavourable suicide mortality trends in Japan. Analysing such trends may shed light on the effect of potentially preventable factors, such as the impact of restricting access to certain popular suicide methods, on overall rates. Therefore, we assessed recent trends in method-specific suicide by gender and age in Japan. METHOD: Suicide mortality and population data between 1990 and 2011 were obtained from the Vital Statistics of Japan and used to calculate method-specific mortality rates. Suicide methods were divided into seven groups: overdose, gases, hanging, drowning, cutting, jumping and other means. Age was divided into four groups: 15-24, 25-44, 45-64 and 65+ years. We applied joinpoint regression to the data and quantified the observed changes. RESULTS: The results of the joinpoint regression analyses showed a sharp increase in overall suicide rates for males and females of all ages until the late 1990s. Suicide from hanging and jumping, in particular, contributed to this increase. After 2000, an increasing trend in overall suicide rates in both males and females aged 15-24 and 25-44 years was observed, with overdose, gases and hanging contributing to this increasing trend. CONCLUSIONS: Our findings revealed that different suicide methods varied in their contribution to the recent overall suicide transition in Japan. Regarding factors associated with the recent increase in suicides by overdose, gases, hanging and jumping, further research is needed in order to promote and implement effective means restriction strategies.


Assuntos
Suicídio/estatística & dados numéricos , Adolescente , Adulto , Idoso , Afogamento , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores Sexuais , Adulto Jovem
6.
J Hand Surg Eur Vol ; 41(2): 198-203, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26221009

RESUMO

UNLABELLED: Trigger fingers with proximal interphalangeal joint flexion contracture are suggested to have a poorer response to corticosteroid injection than those without contracture, though this has not been proven scientifically. We compared the clinical response to corticosteroid injection between trigger fingers with and without proximal interphalangeal joint contracture, and investigated the influence of the injection on the A1 pulley and flexor digitorum tendons using ultrasonography. One month after injection, pain was significantly reduced in the no contracture group, and 56% of trigger fingers with proximal interphalangeal joint contracture resolved. Before injection, relative thickening of the A1 pulley and flexor digitorum tendons, and a partial hypoechoic lesion of the flexor digitorum superficialis tendon were observed in the contracture group. One month after injection, the thickening of the tendons and the A1 pulley was reduced, but the partial hypoechoic lesion was still observed in significant numbers. We have demonstrated that the presence of a proximal interphalangeal joint contracture was associated with a reduced clinical response to corticosteroid injection, and we suggest that the pathologic change in the flexor digitorum superficialis tendon, represented by the partial hypoechoic lesion, contributed to corticosteroid injection resistance. LEVEL OF EVIDENCE: IV.


Assuntos
Corticosteroides/administração & dosagem , Articulações dos Dedos/fisiopatologia , Dedo em Gatilho/tratamento farmacológico , Idoso , Contratura/fisiopatologia , Feminino , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Medição da Dor , Resultado do Tratamento , Dedo em Gatilho/fisiopatologia , Ultrassonografia de Intervenção
7.
Biochim Biophys Acta ; 1089(1): 1-7, 1991 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-2025639

RESUMO

The pyruvate dehydrogenase complex and the alpha-ketoglutarate dehydrogenase complex are multienzyme complexes consisting of three different enzymes. No significant similarity has been reported among the dehydrogenases which are component enzymes of these complexes, despite the presence of homology among the other component enzymes. Here we isolated cDNAs for the alpha and beta subunits of rat pyruvate dehydrogenase and they exhibited a significant similarity of the amino acid sequences among rat pyruvate dehydrogenase, 2-oxoisovalerate dehydrogenase (which is a dehydrogenase component of branched chain alpha-ketoacid dehydrogenase complex) and alpha-ketoglutarate dehydrogenase, suggesting that they have been derived from a common ancestral dehydrogenase. Our results suggested that the alpha and beta subunits of the pyruvate and 2-oxoisovalerate dehydrogenases have been derived by the cleavage of the alpha-ketoglutarate dehydrogenase. However, we could not find significant homology between rat pyruvate dehydrogenase and Gram-negative bacterial pyruvate dehydrogenase.


Assuntos
Azotobacter/enzimologia , Escherichia coli/enzimologia , Complexo Cetoglutarato Desidrogenase/química , Complexo Piruvato Desidrogenase/química , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Complexo Cetoglutarato Desidrogenase/genética , Dados de Sequência Molecular , Complexo Piruvato Desidrogenase/genética , Ratos , Homologia de Sequência do Ácido Nucleico
8.
Biochim Biophys Acta ; 1380(1): 82-92, 1998 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-9545544

RESUMO

Monosialogangliosides (GM1, GM2, GM3 and GM4) were reconstituted in lipid monolayers at the air-water interface. The binding amounts and the initial binding rates of wheat germ agglutinin (WGA) to the monosialoganglioside monolayers were quantitatively studied by use of a quartz-crystal microbalance (QCM). A QCM was horizontally attached to the monolayer from the air phase, and the binding behavior (mass increase) was followed by the frequency decrease of the QCM. WGA binding affinities for the ganglioside monolayers were influenced by hydrophilic head groups of lipid matrices, densities of gangliosides, and sequences of oligosaccharide in gangliosides. Binding of WGA to the gangliosides reconstituted in a phosphatidylcholine (sphingomyelin and distearoylphosphatidylcholine) matrix was strongly suppressed, but not in a neutral glycolipids (GlcCer, GalCer, and LacCer), dipalmitoylphosphatidylethanolamine, and dipalmitoylphosphatidylethanolamine matrix. WGA showed high affinity for monolayers containing 20 mol% gangliosides, but only low affinity for 100% ganglioside monolayers. WGA preferably binds to gangliosides in the following sequence: GM3 > GM4 >> GM2 = GM1. No affinities of WGA for GM2 and GM1 were observed. The combined techniques of monolayer and QCM have the advantages of investigating recognition properties of gangliosides.


Assuntos
Gangliosídeos/química , Gangliosídeos/metabolismo , Aglutininas do Germe de Trigo/química , Aglutininas do Germe de Trigo/metabolismo , Ar , Animais , Sítios de Ligação , Fenômenos Biofísicos , Biofísica , Sequência de Carboidratos , Bovinos , Gangliosídeo G(M1)/química , Gangliosídeo G(M2)/química , Gangliosídeo G(M3)/química , Técnicas In Vitro , Cinética , Dados de Sequência Molecular , Ácido N-Acetilneuramínico/química , Ligação Proteica , Quartzo , Água , Baleias
9.
Leukemia ; 15(7): 1111-7, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11455981

RESUMO

We originally reported that vitamin K2 (VK2) analogs, including menaquinone 4 (MK4) but not vitamin K1, effectively induce apoptosis in various types of primary cultured leukemia cells and leukemia cell lines in vitro. It has also been reported by others that VK2 showed the differentiation-inducing activity in leukemia cell lines. To investigate the discrepancy between apoptosis- and differentiation-inductions of leukemia cells by VK2 treatment, we used bcl-2 gene transfected HL-60 cells (HL-60-bcl-2) which resulted in five-fold over-expression of BCL-2 protein, and then compared the effects of MK4 to the control HL-60-neo cells. Seventy-two hours of exposure to various concentrations of MK4 resulted in growth inhibition of these cells in a dose-dependent manner (0.1-50 microM), however, HL-60-bcl-2 was less sensitive against MK4. MK4 potently induced apoptosis of HL-60-neo cells along with the depolarization of mitochondrial membrane potential and caspase-3 activation. Notably, HL-60-bcl-2 was almost completely resistant to apoptosis induction in response to MK4, although cell growth inhibition was still observed. In spite of the abrogation of apoptosis induction, about 90% of HL-60-bcl-2 cells were arrested in the G0/G1 phase within 48 h of exposure to 10 microM of MK4 accompanied by up-modulation of p27KIP1 expression. Concomitantly, HL-60-bcl-2 cells underwent monocytic differentiation. These data suggest that VK2 also shows the differentiation inducing effects on leukemia cells which are resistant against VK2-inducing apoptosis. The dichotomous nature of VK2 against leukemia cells appears to have clinical benefits for the treatment of patients with leukemias and myelodysplastic syndromes.


Assuntos
Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Leucemia/tratamento farmacológico , Vitamina K/farmacologia , Ciclo Celular/efeitos dos fármacos , Células HL-60 , Humanos , Leucemia/patologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia
10.
Leukemia ; 14(2): 278-84, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10673745

RESUMO

We have investigated the possible role of anti-tumor antibody detected in a case of follicular lymphoma which demonstrated the spontaneous reduction of leukemic tumor cells. The tumor cells genotypically had monoclonal rearrangements of the immunoglobulin J H and C kappa genes, but phenotypically exhibited surface IgG, A, kappa and lambda (kappa lambda dual positivity). The culture study revealed that IgGlambda, at least, was derived from the serum, and IgAkappa was expressed intrinsically. Furthermore, the positive correlation between the densities of both surface light chains on two-color flow cytometry, the rosette formation study and its inhibition test by the Fcgamma fragment suggested that the serum IgGlambda combined with some antigens on the tumor-cell surface via its Fab portion and with the Fcgamma receptor of macrophages via its Fc portion. From these findings, we regarded the present case as an anti-tumor antibody-coated lymphoma. In addition, the phagocytic study disclosed that the serum-derived IgGlambda, at least, might have induced the phagocytosis of circulating lymphoma cells by macrophages. In conclusion, the existence of the anti-tumor antibody-coated lymphoma may be helpful in clarifying the immunological mechanism of the spontaneous regression occasionally seen in lymphomas.


Assuntos
Anticorpos Antineoplásicos/metabolismo , Cadeias kappa de Imunoglobulina/metabolismo , Cadeias lambda de Imunoglobulina/metabolismo , Linfoma Folicular/imunologia , Fagocitose/imunologia , Receptores de IgG/metabolismo , Adulto , Feminino , Citometria de Fluxo , Rearranjo Gênico , Genótipo , Humanos , Imunoglobulina A/metabolismo , Imunoglobulina G/metabolismo , Imunofenotipagem , Linfoma Folicular/patologia , Fenótipo , Remissão Espontânea , Formação de Roseta , Células Tumorais Cultivadas
11.
Leukemia ; 9(12): 2123-6, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8609727

RESUMO

In order to analyze systemic immune surveillance in patients with B cell non-Hodgkin's lymphomas (B-NHL), we investigated circulating lymphocytes using two-color flow cytometry. The proportions of CD3-CD56+ natural killer (NK) cells and CD8++(bright) S6F1++ killer-effector T cells corresponding to activated cytotoxic T lymphocytes (aCTL) were studied in the peripheral blood of 26 patients with indolent lymphoma (IL) and 24 with aggressive lymphoma (AL). The AL patients with both limited disease and advanced disease had an increased proportion of NK cells. However, this feature was not evident in IL patients with either limited or advanced disease. In contrast, an increased proportion of aCTL was observed only in IL patients with advanced disease. These findings indicate that IL may differ from AL in terms of immune surveillance against neoplastic B cells.


Assuntos
Linfoma de Células B/imunologia , Linfócitos T Citotóxicos/patologia , Adulto , Idoso , Antígenos CD/imunologia , Feminino , Humanos , Imunofenotipagem , Linfoma de Células B/sangue , Linfoma de Células B/patologia , Masculino , Pessoa de Meia-Idade
12.
Leukemia ; 13(9): 1399-405, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10482991

RESUMO

We have previously reported that vitamin K2 (VK2) has a potent apoptosis inducing activity toward various types of primary cultured leukemia cells including acute myelogenous leukemia arising from myelodysplastic syndromes (MDS). We established a novel cell line, designated MDS-KZ, from a patient with MDS in blastic transformation, and further investigated the effects of VK2 using this novel cell line. MDS-KZ shows complex chromosomal anomaly including -4, 5q-, -7, 13q+, 20q-, consistent with that seen in the original patient. Culture of MDS-KZ cells in RPMI1640 medium containing 10% FBS lead to steady but very slow proliferation with a doubling time of 14 days. However, the cellular growth rate was significantly accelerated in the presence of various growth factors such as granulocyte colony-stimulating factor, stem cell factor, granulocyte-macrophage colony-stimulating factor, interleukin-3, and thrombopoietin. Most of the cultured cells show the morphological features of myeloblasts. They are positive for CD7, CD33, CD34, CD45, CD117, and HLA-DR. However, about 10% of the cells are more mature metamyelocytes and neutrophils with various dysplastic characteristics such as pseudo-Pelger nuclear anomaly and hypersegmentation, suggesting a potential for differentiation in this cell line. As previously reported for cultured primary leukemia cells, exposure to VK2, but not to VK1, resulted in induction of apoptosis of MDS-KZ cells in a dose-dependent manner (IC50: 5 microM). In addition, VK2 treatment induced down-regulation of BCL-2 and up-regulation of BAX protein expression with concomitant activation of caspase-3 (CPP32). A tetrapeptide functioning as antagonist of caspase-3, Ac-DEVD-H, suppressed the VK2-induced inhibition of cell growth, suggesting that caspase-3 is, at least in part, involved in VK2-induced apoptosis. These observations suggest that the MDS-KZ cell line can serve as a model for the study of the molecular mechanisms of VK2-induced apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Ativação Linfocitária , Síndromes Mielodisplásicas/tratamento farmacológico , Vitamina K/uso terapêutico , Idoso , Caspase 3 , Caspases/metabolismo , Linhagem Celular Transformada , Citocinas/farmacologia , Ativação Enzimática , Feminino , Humanos , Síndromes Mielodisplásicas/enzimologia , Síndromes Mielodisplásicas/patologia
13.
Leukemia ; 12(9): 1392-7, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9737687

RESUMO

We have previously reported that vitamin K2 (VK2) but not VK1 has a potent apoptosis-inducing effect on freshly isolated leukemia cells from patients with various types of leukemia. By multi-color flow cytometric analysis using monoclonal antibody (mAb), APO2.7, which detects mitochondrial 7A6 antigen specifically expressed by cells undergoing apoptosis, we further investigated the apoptosis-inducing effect of VK2 on minor populations of leukemic blast cells in bone marrow from patients with myelodysplastic syndrome (MDS) and overt myeloid leukemia (post-MDS AML). Limiting dilution of CD95 (anti-Fas) mAb-treated apoptotic Jurkat cells with nonapoptotic CTB-1 cells revealed that APO2.7-positive Jurkat cells were consistently detectable by flow cytometry when present at levels of at least 5% in the CTB-1 suspension. In patient samples the gating area for leukemic clone was determined using cell surface antigen-specific mAbs conjugated with either fluorescein isothionate (FITC) or phycoerythrin (PE) and subsequently the cells stained with phycoerythrin cyanine (PE-Cy5)-conjugated APO2.7 mAb were assessed within the gating area of the leukemic clone for monitoring apoptosis. Treatment of the bone marrow mononuclear cells with 3-10 microM of VK2 (menaquinone-3, -4 and -5) in vitro potently induced apoptosis of the leukemic blast cells as compared with the untreated control cells in all 15 MDS patients tested. This effect was more prominent on blastic cells than that on mature myeloid cells such as CD34-/CD33+ gated cells. In addition, VK2 performed much less effectively on CD3-positive lymphoid cells. In contrast to VK2, VK1 did not show apoptosis-inducing activity. These data suggest that VK2 may be used for treatment of patients with MDS in blastic transformation.


Assuntos
Anticorpos Monoclonais/farmacologia , Apoptose , Citometria de Fluxo/métodos , Síndromes Mielodisplásicas/tratamento farmacológico , Vitamina K/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Medula Óssea/efeitos dos fármacos , Medula Óssea/patologia , Humanos , Células Jurkat/efeitos dos fármacos , Proteínas de Membrana/imunologia , Vitamina K/análogos & derivados
14.
Gene ; 261(1): 53-62, 2000 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-11164037

RESUMO

The human genome, as in other eukaryotes, has a wide heterogeneity in the DNA base composition. The evolutionary basis for this heterogeneity has been unknown. A previous study of the human genome (846 genes analyzed) has shown that, in the major range of the G+C content in the third codon position (0.25-0.75), biases from the Parity Rule 2 (PR2) among the synonymous codons of the four-codon amino acids are similar except in the highest G+C range (Sueoka, N., 1999. Translation-coupled violation of Parity Rule 2 in human genes is not the cause of heterogeneity of the DNA G+C content of third codon position. Gene 238, 53-58.). PR2 is an intra-strand rule where A=T and G=C are expected when there are no biases between the two complementary strands of DNA in mutation and selection rates (substitution rates). In this study, 14,026 human genes were analyzed. In addition, the third codon positions of two-codon amino acids were analyzed. New results show the following: (a) The G+C contents of the third codon position of human genes are scattered in the G+C range of 0.22-0.96 in the third codon position. (b) The PR2 biases are similar in the range of 0.25-0.75, whereas, in the high G+C range (0.75-0.96; 13% of the genes), the PR2-bias fingerprints are different from those of the major range. (c) Unlike the PR2 biases, the G+C contents of the third codon position for both four-codon and two-codon amino acids are all correlated almost perfectly with the G+C content of the third codon position over the total G+C ranges. These results support the notion that the directional mutation pressure, rather than the directional selection pressure, is mainly responsible for the heterogeneity of the G+C content of the third codon position.


Assuntos
Composição de Bases , Códon/genética , DNA/genética , Genes/genética , Aminoácidos/genética , Bases de Dados Factuais , Evolução Molecular , Frequência do Gene , Variação Genética , Genoma Humano , Humanos , Mutação , Seleção Genética
15.
FEBS Lett ; 260(1): 67-9, 1990 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-2105236

RESUMO

Members of the RNA-binding protein superfamily contain RNA binding domains of about 90 amino acids with a highly conserved motif 'GFGF'. Using the conserved motif with some variations G-(F/Y)-(G/A)-(F/Y)-(V/I)-X-(F/Y) as a probe, we screened protein sequences carrying identical amino acids in an NBRF-protein database. It has been found that the C-terminal portion of clustered asparagine-rich protein (CARP), a malaria antigen from Plasmodium falciparum, shows an unexpected sequence similarity with the RNA-binding protein superfamily for the C-terminal half of the RNA-binding domain. Dot matrix comparisons and alignment of these sequences as well as a statistical test have revealed highly significant sequence similarities. From these analyses, we conclude that the malaria antigen CARP belongs to a large family of the RNA-binding proteins. An evolutionary implication of the sequence similarity was also discussed.


Assuntos
Antígenos de Protozoários/isolamento & purificação , Asparagina/análise , Proteínas de Transporte/isolamento & purificação , Malária/parasitologia , Plasmodium falciparum/imunologia , Sequência de Aminoácidos , Animais , Malária/genética , Técnicas de Sonda Molecular , Dados de Sequência Molecular , Plasmodium falciparum/genética , Proteínas de Ligação a RNA , Homologia de Sequência do Ácido Nucleico
16.
Leuk Res ; 24(4): 359-66, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10713334

RESUMO

Refractory anemia (RA) in myelodysplastic syndrome (MDS) without prominent dysplasia closely resemble the mild type of aplastic anemia (AA) in their hematological features. This sometimes makes it difficult to distinguish clearly between the two diseases. Using the multi-color flow cytometric technique, we compared cell surface antigen expression patterns on bone marrow hematopoietic progenitor cells which were isolated as a CD34 positive- CD45 dull positive with low side scatter intensity (CD34(+)CD45(dull+)SSC(low)) population in flow cytogram between RA (n=12) and AA (n=11). The antigens analyzed in CD34(+)CD45(dull+)SSC(low) mononuclear cells were: CD38 and CD71 for cell growth-related antigens, CD 33 and CD13 for myeloid and monocytoid lineage-associated antigens, CD7 and CD19 for lymphoid lineage, and CD14 for a monocytic lineage specific antigen. The percentages of CD34(+)CD45(dull+)SSC(low) cells in bone marrow non-erythroid mononuclear cells, and the expression frequencies of CD38, CD71, CD33 and CD13 antigens in CD34(+)CD45(dull+)SSC(low) progenitors were all significantly decreased in AA compared to normal bone marrows (n=7) (P<0.005). In contrast, in RA bone marrows the percentages of CD34(+)CD45(dull+)SSC(low) cells showed wide distribution and the cell surface antigen expression patterns varied among each case: some cases showed low frequencies of CD38 and CD71 expression as well as AA, whereas the others showed high expression frequency of specific antigen(s) which may reflect the clonal expansion of an abnormal clone in bone marrow. An MDS patient who had progressed from RA to RAEB showed further projecting pattern of expression of CD38 and CD33 in CD34(+)CD45(dull+)SSC(low) population in accordance with the disease progression. These data suggest that analysis of cell surface antigen expression patterns of CD34(+)CD45(dull+)SSC(low) progenitor cells by multi-color flow cytometry appears to be a useful method for qualitative and quantitative assessment of marrow progenitor states in AA and RA, therefore this method could be helpful for early detection of clonal evolution in MDS.


Assuntos
Anemia Aplástica/imunologia , Anemia Refratária/imunologia , Antígenos CD , Antígenos de Superfície/análise , Células da Medula Óssea/imunologia , Citometria de Fluxo , Células-Tronco Hematopoéticas/imunologia , ADP-Ribosil Ciclase , ADP-Ribosil Ciclase 1 , Adulto , Idoso , Antígenos CD34/análise , Antígenos de Diferenciação/análise , Humanos , Antígenos Comuns de Leucócito/análise , Glicoproteínas de Membrana , Pessoa de Meia-Idade , NAD+ Nucleosidase/análise
17.
Am J Med Genet ; 96(2): 141-5, 2000 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-10893485

RESUMO

The cholecystokinin A receptor (CCK-AR) modulates CCK-stimulated dopamine release in the posterior nucleus accumbens, and its gene is mapped to 4p15.2-15.1 with the dopamine receptor 5 (DR5) gene. We speculated that alterations in the CCK-AR lead to an increase in dopamine release, which may in turn constitute a predisposition in schizophrenia. We investigated genetic variations in the promoter region and the coding region of the CCK-AR gene. An association analysis was conducted between 83 unrelated schizophrenic patients and 80 healthy controls. Novel polymorphisms (201A-->G, 246G-->A in the promoter region, 1260T-->A, 1266T-->C in intron 1 within the 3' mRNA splice acceptor site consensus sequence, and Leu306Leu in exon 5) were found in addition to the variants (608G-->A in intron 1, 3849C-->T [Ile296Ile] in exon 5) reported previously. Significant differences were found in the allele frequencies of the 201A-->G nucleotide substitution in the promoter region between patients and controls (P = 0.0181, odds ratio: 1.972, after Bonferroni correction: P = 0.0543). These differences were also found between the patients with paranoid type and controls (P = 0.0274, odds ratio = 3.667, after Bonferroni correction: P = 0.0822). Our analyses suggest that the 201A allele frequency was higher in the schizophrenic group, especially in the paranoid type, than in the control group at a rate that was not quite significant after Bonferroni correction. Am J. Med Genet. (Neuropsychiatr. Genet.) 96:141-145, 2000.


Assuntos
Predisposição Genética para Doença/genética , Polimorfismo Genético/genética , Receptores da Colecistocinina/genética , Esquizofrenia/genética , Adulto , Feminino , Predisposição Genética para Doença/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Regiões Promotoras Genéticas/genética , Receptor de Colecistocinina A , Esquizofrenia/etiologia
18.
Am J Med Genet ; 88(6): 700-4, 1999 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-10581492

RESUMO

Genetic variations in the 5'-untranslated region and the coding region of the CCK-B receptor (CCK-BR) gene were investigated in healthy controls. Novel variants (-215 C-->A, Leu37Phe, Arg319Glu) were found in addition to the mutations (Val125Iso, His207His, Arg215His, 2491 C-->A) reported previously. In the present study, association analysis was carried out for these variants between 80 unrelated schizophrenic patients and 100 healthy controls. The genotype frequency of the -215 C-->A nucleotide substitution in the 5'-untranslated region of CCK-BR gene was significantly higher in the schizophrenic patients than in the controls (6.25%, P = 0.037). However, the difference was not significant after Bonferroni correction for multiple comparisons. Moreover, no association was found between the clinical characteristics of the patients and the genotype frequencies of the variants. These results suggest that the CCK-BR gene polymorphisms have no association with schizophrenia nor its clinical heterogeneity. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 88:700-704, 1999.


Assuntos
Éxons/genética , Polimorfismo Genético/genética , Regiões Promotoras Genéticas/genética , Receptores da Colecistocinina/genética , Esquizofrenia/genética , Regiões 5' não Traduzidas/genética , Adulto , Substituição de Aminoácidos/genética , Estudos de Casos e Controles , Feminino , Frequência do Gene/genética , Predisposição Genética para Doença , Variação Genética/genética , Genótipo , Humanos , Íntrons/genética , Masculino , Pessoa de Meia-Idade , Mutação/genética , Razão de Chances , Polimorfismo Conformacional de Fita Simples , Receptor de Colecistocinina B
19.
Am J Med Genet ; 81(5): 434-9, 1998 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-9754630

RESUMO

Dysfunction of serotonin systems has been implicated in schizophrenia. In the present study, the human 5-HT1A receptor gene containing the 5' untranslated region was screened in order to detect genetic variations, through which alteration of protein function or level of expression might contribute to schizophrenia. Genomic DNAs were isolated from whole-blood samples of 61 unrelated schizophrenic patients and 100 healthy controls. Genetic variations were screened systematically by single-strand conformational polymorphism (SSCP) analysis, followed by direct sequencing of polymerase chain reaction (PCR) product as well as restriction fragment-length polymorphism (RFLP). The novel mutations (-51T --> C, -152C --> G, -321G --> C, -480delA, and -581C --> A) were found in the 5' untranslated region. Furthermore, we found a novel missense mutation (Gly272Asp) in the coding region in addition to the mutations (Pro16Leu, 294G --> A, and 549C --> T) reported previously. No significant differences in genotype frequencies as well as allele frequencies were found between patients and controls. Our data provided no evidence of association between schizophrenia and the variants in the 5' untranslated region as well as the coding region of the human 5-HT1A receptor gene.


Assuntos
Genoma Humano , Mutação , Regiões Promotoras Genéticas/genética , Receptores de Serotonina/genética , Esquizofrenia/genética , Marcadores Genéticos , Predisposição Genética para Doença , Humanos
20.
Bone Marrow Transplant ; 19(10): 1001-9, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9169644

RESUMO

Recipients of marrow from alternative donors (unrelated or HLA-mismatched related donors) have a higher incidence of post-transplant complications compared to recipients of marrow from HLA-identical siblings. HLA disparity undetected by routine typing techniques has been suggested as one cause for the increased complications observed. Limiting dilution analysis (LDA) of donor-derived, host-reactive T cell precursor frequency prior to transplant has been proposed as a surrogate indicator of underlying HLA disparity which might be used to predict transplant outcome and aid in donor selection. We compared results of LDA of host-reactive IL-2 producing helper T lymphocytes (HTLp) and/or cytolytic T lymphocytes (CTLp) in 77 alternative marrow donor/recipient pairs with transplant outcome using univariate and multivariate analysis. All donor grafts were depleted ex vivo of mature T cells. Median patient age was 15 years (1-53). Donor selection was based on serologic typing for HLA class I and high resolution oligotyping for HLA-DRB1-DRB5, and HLA-DQB1. HLA-A and HLA-B locus antigens were retrospectively defined by one dimensional isoelectric focusing (IEF). Cox proportional hazards regression models were used to assess the impact of frequency and estimated cell dose of CTLp and HTLp on outcome. The CTLp assay was most sensitive to HLA-A and HLA-B locus disparity detected by serology or IEF. The HTLp assay detected class I disparity but was most strongly reactive in the presence of HLA-DRB1 disparity. Univariate analysis indicated a significant association of CTLp frequency and dose with severe (grades 3-4) acute graft-versus-host disease (GVHD), and of CTLp dose with chronic GVHD. Both assays were associated with survival and neither assay was associated with relapse. After adjustment for other significant covariables including known HLA disparity, the association of CTLp with acute GVHD was lost, however, CTLp frequency and CTLp dose remained associated with survival and HTLp frequency was associated with chronic GVHD. These data support the hypothesis that post-BMT complications may be influenced not only by T cell dose but by the alloreactive potential of the cells infused. LDA of alloreactive potential was useful in detecting disparity and in predicting survival or chronic GVHD in recipients of alternative donor TCD marrow grafts.


Assuntos
Transplante de Medula Óssea/imunologia , Transplante de Medula Óssea/métodos , Linfócitos T Citotóxicos/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Adolescente , Adulto , Purging da Medula Óssea , Transplante de Medula Óssea/efeitos adversos , Criança , Pré-Escolar , Feminino , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/imunologia , Antígenos HLA , Teste de Histocompatibilidade , Humanos , Lactente , Depleção Linfocítica , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Doadores de Tecidos , Transplante Homólogo
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