Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 328
Filtrar
1.
J Appl Microbiol ; 131(3): 1515-1530, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33570830

RESUMO

AIMS: To reveal the sources of Aeromonas infection in Okinawa Prefecture of Japan, the species, virulence genes and clones of strains isolated from clinical specimens and well water were compared. METHODS AND RESULTS: The properties of both isolates were investigated by sequencing of rpoD, detection of 10 virulence genes using PCR and genotyping with pulsed-field gel electrophoresis. In all, 68 clinical and 146 well water strains of Aeromonas were isolated and the main species were A. caviae, A. dhakensis, A. hydrophila and A. veronii biovar sobria. Aeromonas dhakensis possessed various virulence genes; however, A. caviae possessed only fla. The same or similar clones were distributed in certain areas of Okinawa and one clone had survived several months in the biliary system of two patients, respectively. CONCLUSION: Although the same Aeromonas clone was not isolated from clinical and well water samples, our study revealed the detected patterns of virulence genes in both isolates, the distribution of identical/similar clones in the Okinawan environment and long-time survival in patient's organs. SIGNIFICANCE AND IMPACT OF THE STUDY: We investigated the association between Aeromonas patients and well water exposure. This study provides the properties of species, virulence genes and clones of Aeromonas isolated from samples of these origins.


Assuntos
Aeromonas , Água Potável/microbiologia , Infecções por Bactérias Gram-Negativas , Virulência , Aeromonas/genética , Aeromonas/patogenicidade , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Japão , Virulência/genética
2.
Hernia ; 25(5): 1279-1287, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33128678

RESUMO

PURPOSE: Bowel wall enhancement on CT imaging is considered one of the useful features for the prediction of the presence of irreversible ischemic change in patients with small bowel obstruction. However, the applicability of CT imaging in patients with incarcerated hernias has not been investigated in detail. The aim of this retrospective study was to evaluate the feasibility of preoperative CT findings for the prediction of the presence of irreversible ischemic change in patients with incarcerated hernias containing small bowel. METHODS: Included in this study were 76 patients who underwent surgery for preoperatively diagnosed incarcerated hernias containing small bowel (27 inguinal hernias, 37 femoral hernias and 12 obturator hernias) at our hospital between January 2011 and June 2020. The preoperative clinicoradiological features were compared between the groups, and predictors for intestinal resection were evaluated. RESULTS: Nineteen patients required intestinal resection (Resection group), and the other 57 patients did not require intestinal resection (Nonresection group). Multivariate analyses revealed that age ≥ 80 years (p = 0.018, odds ratio = 6.604) and the absence of bowel wall enhancement (p = 0.032, odds ratio = 51.200) were independent predictors for intestinal resection. In resected specimens, all patients with an absence of bowel wall enhancement on preoperative enhanced CT had ischemic changes extending beyond the muscularis propria. CONCLUSIONS: Preoperative enhancement CT yields useful information for the prediction of the presence of irreversible ischemic change in patients with incarcerated hernias containing small bowel.


Assuntos
Hérnia Inguinal , Hérnia do Obturador , Obstrução Intestinal , Idoso de 80 Anos ou mais , Hérnia Inguinal/cirurgia , Hérnia do Obturador/cirurgia , Herniorrafia , Humanos , Obstrução Intestinal/diagnóstico por imagem , Obstrução Intestinal/etiologia , Obstrução Intestinal/cirurgia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
3.
Rev Sci Instrum ; 85(2): 02A959, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593538

RESUMO

The Kei-source is a compact electron cyclotron resonance ion source using only permanent magnets and a frequency of 10 GHz. It was developed at the National Institute of Radiological Sciences (NIRS) for producing C(4+) ions oriented for high-energy carbon therapy. It has also been used as an ion source for the NIRS-930 cyclotron. Its microwave band region for the traveling-wave-tube amplifier and maximum output power are 8-10 GHz and 350 W, respectively. Since 2006, it has provided various ion beams such as proton, deuteron, carbon, oxygen, and neon with sufficient intensity (200 µA for proton and deuteron, 50 µA for C(4+), for example) and good stability for radioisotope production, tests of radiation damage, and basic research experiments. Its horizontal and vertical emittances were measured using a screen monitor and waist-scan. The present paper reports the current status of the Kei-source.


Assuntos
Ciclotrons/instrumentação , Elétrons , Radiologia/instrumentação , Imãs , Imagem Molecular
4.
J Laryngol Otol ; 122(2): 155-60, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17592661

RESUMO

OBJECTIVES: To determine the characteristics of causative factors of taste disorders amongst the elderly, and to examine the therapeutic effect of a zinc agent, taking into account age-related factors. SUBJECTS: A total of 408 patients with taste disorders were divided into three groups by age: 49 years or younger, 50 to 64 years old, and 65 years or older. RESULTS: The incidence of taste disorders caused by drug administration and systemic disease were significantly higher in the elderly group. A serum zinc concentration of 69 microg/dl or lower was found in 33 per cent of the elderly group, significantly more (p < 0.001) than the 19 per cent of the 49 years or younger group with such a concentration. Zinc administration was therapeutically effective in 70 per cent of the whole population studied, and in 74 per cent of the elderly population. CONCLUSIONS: In the elderly, the incidence of taste disorders caused by drug administration or systemic disease was significantly greater compared with other age groups. The curative effects of zinc administration were not observed to be influenced by age.


Assuntos
Distúrbios do Paladar/etiologia , Zinco/uso terapêutico , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
5.
Eur Respir J ; 22(5): 739-42, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14621078

RESUMO

The aim of the study was to determine whether the amount of urinary trypsin inhibitor (UTI) in serum, a degenerate induced by neutrophil elastase (NE), reflects the degree of bronchial inflammation in children with acute asthma exacerbation. The involvement of neutrophil-mediated inflammation plays as important a role as eosinophil-mediated inflammation in the pathogenesis of acute asthma exacerbation. However, no measurable marker is sensitive enough to assess neutrophil-mediated inflammation in the airways. The pre-alpha-/inter-alpha-trypsin inhibitors are assumed to be precursors of UTI. NE degrades pre-alpha-/inter-alpha-trypsin inhibitors to liberate UTI. UTI concentrations in 25 childhood patients admitted with asthma exacerbation and 15 control subjects were measured by means of one-step sandwich-type enzyme immunoassay. Serum UTI concentrations in the patients at admission were significantly higher than control values (10.597+/-0.649 and 6.136+/-0.303 U x mL(-1), respectively (mean+/-SEM)). These levels returned to baseline values with improvement in the asthmatic symptoms. However, serum NE and alpha1 antitrypsin concentrations were not significantly different between patients and controls, even during acute exacerbation in the former. The findings suggest that neutrophil-mediated inflammatory events are involved in exacerbation of childhood asthma. The monitoring of urinary trypsin inhibitor concentrations might be useful for evaluating the neutrophil-mediated inflammation in childhood asthma attack.


Assuntos
Asma/sangue , Glicoproteínas/sangue , Inibidores da Tripsina/sangue , Doença Aguda , Asma/fisiopatologia , Biomarcadores/sangue , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Contagem de Leucócitos , Elastase de Leucócito/sangue , Masculino , Neutrófilos , Inibidores Teciduais de Metaloproteinases/sangue , alfa 1-Antitripsina/análise
6.
Appl Microbiol Biotechnol ; 60(1-2): 160-7, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12382058

RESUMO

In lactic acid bacteria, pentoses are metabolized via the phosphoketolase pathway, which catalyzes the cleavage of D-xylulose-5-phosphate to equimolar amounts of glyceraldehyde 3-phosphate and acetylphosphate. Hence the yield coefficient of lactate from pentose does not exceed 1.0 mol/mol, while that of Lactococcus lactis IO-1(JCM7638) at high D-xylose concentrations often exceeds the theoretical value. This suggests that, in addition to the phosphoketolase pathway, L. lactisIO-1 may possess another metabolic pathway that produces only lactic acid from xylose. In the present study, the metabolism of xylose in L. lactisIO-1 was deduced from the product formation and enzyme activities of L. lactisIO-1 in batch culture and continuous culture. During cultivation with xylose concentrations above ca. 50 g/l, the yield coefficient of L-lactate exceeded 1.0 mol/mol while those of acetate, formate and ethanol were very low. At xylose concentrations less than 5 g/l, acetate, formate and ethanol were produced with yield coefficients of about 1.0 mol/mol, while L-lactate was scarcely produced. In cells grown at high xylose concentrations, a marked decrease in the specific activities of phosphoketolase and pyruvate formate lyase (PFL), and an increase in those of transketolase and transaldolase were observed. These results indicate that in L. lactisIO-1 xylose may be catabolized by two different pathways, the phosphoketolase pathway yielding acetate, formate and ethanol, and the pentose phosphate (PP)/glycolytic pathway which converts xylose to L-lactate only. Furthermore, it was deduced that the change in the xylose concentration in the culture medium shifts xylulose 5-phosphate metabolism between the phosphoketolase pathway and the PP/glycolytic pathway in L. lactisIO-1, and pyruvate metabolism between cleavage to acetyl-CoA and formic acid by PFL and the reduction to L-lactate by lactate dehydrogenase.


Assuntos
Glicólise , Ácido Láctico/metabolismo , Lactococcus lactis/metabolismo , Xilose/metabolismo , Enzimas/metabolismo , Fermentação , Lactococcus lactis/enzimologia , Lactococcus lactis/crescimento & desenvolvimento , Via de Pentose Fosfato/fisiologia , Xilose/antagonistas & inibidores
7.
Biochim Biophys Acta ; 1522(1): 59-61, 2001 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-11718901

RESUMO

Nippostrongylus brasiliensis (Nb) is one of the most important parasites in studying Th2 immune response of the host, but little is known about its antigenic structures of the excretory-secretory or structural proteins of the parasite. Here we report cloning and characterization of a novel antigenic gene from cDNA library of Nb adult worm by immunoscreening. The positive clone, KLP-Nb, had an open reading frame of 612 bp that encodes a 203-amino-acid protein and was homologous to 'similar to keratins in a glycine-rich region' of Caenorhabditis elegans. Its expression was confirmed by Northern blotting and IgG enzyme-linked immunosorbent assay. This protein seems to be one of the components of cuticle that covers the nematode body.


Assuntos
Queratinas/genética , Nippostrongylus/genética , Sequência de Aminoácidos , Animais , Clonagem Molecular , Queratinas/química , Dados de Sequência Molecular , Nippostrongylus/química , Fases de Leitura Aberta , Alinhamento de Sequência
8.
Clin Exp Immunol ; 125(2): 283-90, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11529921

RESUMO

We have reported previously that the abnormally down-regulated protein kinase C (PKC) causes cellular dysfunction observed in natural killer (NK) cells, polymorphonuclear leucocytes (PMNs) and fibroblasts from beige mouse, an animal model of Chediak-Higashi syndrome (CHS). Here we show that the abnormal down-regulation of PKC activity also occurs in Epstein-Barr (EB) virus-transformed cell lines from CHS patients. When CHS cell lines were stimulated with concanavalin A (Con A) for 20 min, the membrane-bound PKC activity declined markedly, whereas that in control cell lines increased. We found that E-64-d, which protects PKC from calpain-mediated proteolysis, reversed the declined PKC activity and corrected the increased Con A cap formation to almost normal levels in CHS cell lines. We confirmed that the dysregulation of PKC activity also occurred in peripheral blood mononuclear leucocytes (PBMC) from CHS patients and that E-64-d corrected both the declined PKC activity and increased Con A cap formation. E-64-d also corrected the reduced lysosomal elastase and cathepsin G activity in CHS cell lines. In contrast, chelerythrin, a specific inhibitor of PKC, and C2-ceramide, which promotes PKC breakdown induced by calpain, increased Con A cap formation and inhibited both elastase and cathepsin G activity in normal cell lines. Moreover, we found that ceramide production in CHS cell lines increased significantly after Con A stimulation, which coincides with our previous observation in fibroblasts from CHS mice. These results suggest an association between ceramide-induced PKC down-regulation and the cellular dysfunctions in CHS.


Assuntos
Síndrome de Chediak-Higashi/enzimologia , Concanavalina A/farmacologia , Inibidores de Cisteína Proteinase/farmacologia , Leucina/farmacologia , Leucócitos Mononucleares/enzimologia , Lisossomos/enzimologia , Proteína Quinase C/metabolismo , Calpaína/antagonistas & inibidores , Catepsina G , Catepsinas/metabolismo , Linhagem Celular Transformada , Ceramidas/biossíntese , Síndrome de Chediak-Higashi/imunologia , Criança , Regulação para Baixo , Antagonismo de Drogas , Feminino , Humanos , Leucina/análogos & derivados , Leucócitos Mononucleares/efeitos dos fármacos , Masculino , Elastase Pancreática/metabolismo , Agregação de Receptores/efeitos dos fármacos , Serina Endopeptidases , Esfingomielina Fosfodiesterase/metabolismo
10.
Clin Immunol ; 100(2): 250-9, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11465955

RESUMO

The mechanism of hypergammaglobulinemia in patients infected with HIV has remained unclear in spite of the identification of a reduction of CD4+ T cells. The amounts of CD27+ memory B cells were remarkably reduced in the peripheral blood and immunoglobulin (Ig) production was diminished in HIV-infected patients. Some of the freshly isolated patients' T cells expressed the CD70 (CD27 ligand) on the surface and the CD70 expression on both of the CD4+ and CD8+ T cells was greatly enhanced by various stimuli. It was also striking that plasmacytosis was observed in patients' bone marrow. Thus, our findings suggest that CD70 expressed spontaneously or by activation on T cells of HIV-infected patients stimulates memory B cells via CD27 and promotes their differentiation into plasma cells, resulting in the elevation of serum Ig levels and the elimination of circulating memory B cells in HIV-infected patients.


Assuntos
Antígenos CD , Linfócitos B/imunologia , Infecções por HIV/imunologia , Hipergamaglobulinemia/imunologia , Plasmócitos/imunologia , Adulto , Sequência de Aminoácidos , Ligante CD27 , Pré-Escolar , Feminino , Infecções por HIV/complicações , Humanos , Hipergamaglobulinemia/complicações , Masculino , Proteínas de Membrana/imunologia , Pessoa de Meia-Idade , Dados de Sequência Molecular , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia
11.
Clin Exp Immunol ; 124(3): 461-4, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11472408

RESUMO

The B-cell lineage in a patient with B-cell-negative severe combined immunodeficiency (SCID) was analysed by using antisurrogate light chain (SL) MoAbs. Peripheral CD3(+) T cells and CD19(+) B cells were absent in the patient. The common gamma (gamma c) chain was expressed normally on the patient's peripheral NK cells and his peripheral mononuclear cells did not possess any mutations in recombinase activating gene (RAG)-1, 2. Normal levels of expression of Ku70 and Ku80 protein were found by Western blot analysis. The patient did, however, display an increase in fibroblast sensitivity to irradiation. Furthermore, flow cytometric analyses of bone marrow cells showed that surface IgM and cytoplasmic mu positive cells were absent and that CD19(+) B cells were composed of only CD34(+) terminal deoxynucleotidyl transferase (TdT)(+) SL(+) pro-B cells. The complete arrest of pro- to pre-B cell development in the SCID patient's bone marrow suggests that some genes involved in V(D)J recombination, excepting the RAG gene, may play a causative role in the immunodeficiency.


Assuntos
Linfócitos B/citologia , Células da Medula Óssea/citologia , Proteínas de Ligação a DNA/genética , Células-Tronco Hematopoéticas/citologia , Proteínas de Homeodomínio/genética , Mutação , Imunodeficiência Combinada Severa/genética , Antígenos CD/análise , Linfócitos B/imunologia , Células da Medula Óssea/imunologia , Diferenciação Celular , Linhagem Celular Transformada , Linhagem da Célula , Feminino , Células-Tronco Hematopoéticas/imunologia , Humanos , Lactente , Masculino , Proteínas Nucleares , Linhagem , Imunodeficiência Combinada Severa/sangue , Imunodeficiência Combinada Severa/imunologia
12.
Transfusion ; 41(5): 615-20, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11346696

RESUMO

BACKGROUND: Alloimmune neonatal neutropenia (ANN) is caused by a reaction of maternal alloantibodies with paternally inherited antigens on the fetal neutrophils. While human neutrophil antigens (HNA) antibodies are found in half of ANN cases, specific antibodies have not been defined in the remaining cases. STUDY DESIGN AND METHODS: Reported here is a neonate with omphalitis due to neutropenia. To elucidate the cause of ANN, flow cytometric and PCR analyses were used. Reactions of the patient's and mother's sera with neutrophils, lymphocytes, and platelets were examined by lymphocytotoxicity test (LCT), anti-human immunoglobulin-LCT, and mixed passive hemagglutination test. RESULTS: The maternal sera reacted with neutrophils, lymphocytes, and platelets of the patient and father. The platelet adsorption eliminated the reaction of the maternal serum with the patient's neutrophils. The HLA typing of the family and an LCT using a panel of lymphocytes of 20 HLA-typed donors showed HLA-A2 antigen as a target of antibodies in the maternal serum. According to anti-human immunoglobulin-LCT, the anti-HLA-A2 was present in the neonatal serum. On the other hand, HNA antibodies were not detectable in the patient's or the mother's serum. CONCLUSION: These results suggest that the transplacental passage of the maternal HLA antibody caused neutropenia in this patient.


Assuntos
Antígenos HLA/imunologia , Isoanticorpos/imunologia , Neutropenia/etiologia , Adulto , Feminino , Humanos , Recém-Nascido , Masculino
13.
Int J Hematol ; 73(1): 87-92, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11372761

RESUMO

The use of theophylline in the treatment of obstructive pulmonary diseases has diminished with the advent of new medications. However, its use as a second-line bronchodilator has been reconsidered in recent years. Theophylline is reported to have immunomodulatory actions that may account for its clinical effectiveness in the control of airway inflammation. Theophylline, even at low plasma concentrations, inhibits the late asthmatic reaction following allergen challenge. The apparent suppression of airway inflammation by theophylline reinforces findings from in vitro experiments (including our recent studies). Its immunomodulatory actions include inhibition of cytokine synthesis and release, inhibition of inflammatory cell activation, and acceleration of granulocyte apoptosis. On the basis of these findings, theophylline has been re-evaluated as a key drug for the long-term management of bronchial asthma, and new applications are proposed for the clinical use of xanthine derivatives. Here, we review some recent advances in the understanding of pharmacological actions and new applications of xanthine derivatives.


Assuntos
Teofilina/farmacologia , Adjuvantes Imunológicos/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Humanos , Leucócitos/citologia , Leucócitos/fisiologia , Inibidores de Fosfodiesterase/farmacologia , Antagonistas de Receptores Purinérgicos P1 , Teofilina/uso terapêutico
14.
J Neurol Sci ; 185(2): 89-93, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11311288

RESUMO

Previous studies have shown that activation of blood coagulation and fibrin depositions around CNS vessels are observed in animals with experimental autoimmune encephalomyelitis (EAE), which provides an animal model for human autoimmune demyelinating disorders. We examined the values of peripheral blood fibrinogen, thrombin-antithrombin III complex (TAT), fibrinolytic activity, and fibrin degradation products in Lewis rats with EAE to elucidate the role of the blood coagulation-fibrinolysis system in EAE. Plasma TAT values increased immediately prior to development of symptoms, and decreased according to the improvement of symptoms. There was significant correlation between TAT values and clinical scores of EAE; other markers were not correlated with the symptoms of EAE. These results suggest that plasma TAT levels are sensitive markers of the severity of EAE, and may be useful clinical indicators for the severity of human autoimmune demyelinating disorders.


Assuntos
Antitrombina III/metabolismo , Transtornos da Coagulação Sanguínea/sangue , Coagulação Sanguínea/imunologia , Encefalomielite Autoimune Experimental/sangue , Trombina/metabolismo , Animais , Antitrombina III/imunologia , Bioensaio , Transtornos da Coagulação Sanguínea/imunologia , Transtornos da Coagulação Sanguínea/fisiopatologia , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/fisiopatologia , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Fibrinogênio/metabolismo , Fibrinólise/imunologia , Ratos , Ratos Endogâmicos Lew , Medula Espinal/imunologia , Medula Espinal/patologia , Medula Espinal/fisiopatologia , Trombina/imunologia
15.
Blood ; 97(9): 2561-7, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11313242

RESUMO

Neutrophil-specific granule deficiency (SGD) is a rare congenital disorder. The neutrophils of individuals with SGD display atypical bi-lobed nuclei, lack expression of all secondary and tertiary granule proteins, and possess defects in chemotaxis, disaggregation, receptor up-regulation, and bactericidal activity, resulting in frequent and severe bacterial infections. Previously, a homozygous mutation in the CCAAT/enhancer binding protein-epsilon (C/EBPepsilon) gene was reported for one case of SGD. To substantiate the role of C/EBPepsilon in the development of SGD and elucidate its mechanism of inheritance, the mutational status of the gene was determined in a second individual. An A-nucleotide insertion in the coding region of the C/EBPepsilon gene was detected. This mutation completely abolished the predicted translation of all C/EBPepsilon isoforms. Microsatellite and nucleotide sequence analyses of the C/EBPepsilon locus in the parents of the proband indicated that the disorder may have resulted from homozygous recessive inheritance of the mutant allele from an ancestor shared by both parents. The mutant C/EBPepsilon(32) protein localized in the cytoplasm rather than the nucleus and was unable to activate transcription. Consistent with this, a significant decrease in the levels of the messenger RNAs (mRNAs) encoding the secondary granule protein human 18-kd cationic antimicrobial protein (hCAP-18)/LL-37 and the primary granule protein bactericidal/permeability-increasing protein were observed in the patient. The hCAP-18 mRNA was induced by overexpression of C/EBPepsilon(32) in the human myeloid leukemia cell line, U937, supporting the hypothesis that C/EBPepsilon is a key regulator of granule gene synthesis. This study strongly implicates mutation of the C/EBPepsilon gene as the primary genetic defect involved in the development of neutrophil SGD and defines its mechanism of inheritance.


Assuntos
Proteínas Estimuladoras de Ligação a CCAAT/genética , Mutação da Fase de Leitura , Neutropenia/genética , Adulto , Grânulos Citoplasmáticos , Feminino , Genes Recessivos , Homozigoto , Humanos , Neutropenia/congênito , Neutropenia/etiologia , Neutropenia/patologia , Neutrófilos/patologia
16.
Cancer Res ; 61(8): 3361-8, 2001 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11309293

RESUMO

The seco-steroid hormone, 1alpha,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] inhibits proliferation and induces differentiation of malignant cells including those of the hematopoietic system. The 24-oxo metabolite of 1,25(OH)(2)D(3) also has prominent antiproliferative activities against various cancer cells. We chemically synthesized five novel 24-oxo vitamin D(3) analogues and evaluated their abilities both to inhibit clonal growth and induce differentiation of myeloid leukemia cells and to cause hypercalcemia. The 1alpha,25-dihydroxy-16-ene-D(3) [1,25(OH)(2)-16-ene-D(3)] and 1alpha,25-dihydroxy-16-ene-19-nor-D(3) [1,25(OH)(2)-16-ene-19-nor-D(3)] and their 24-oxo metabolites showed greater potency than 1,25(OH)(2)D(3) in their abilities to inhibit clonal proliferation of HL-60, NB4, and U937 leukemic cell lines as measured by methylcellulose soft-gel assay. Their inhibition of clonal growth was irreversible as analyzed by pulse exposure studies. The synthetic analogues also had greater potency than 1,25(OH)(2)D(3) to induce differentiation of HL-60 and NB4 cells as measured by generation of superoxide, nonspecific esterase production, and induction of CD11b and CD14 cell surface antigens and to increase the proportion of these cells in the G(0)-G(1) phase of the cell cycle. For most assays, the 24-oxo metabolite was slightly more potent than the unmodified analogue, and 50% activity was usually found in the nanomolar range. These analogues and their 24-oxo metabolites also inhibited fresh leukemic cell clonal proliferation. Expression of p27(KIP1), a cyclin-dependent kinase inhibitor that plays an important role in blocking the cell cycle, was found by Western blot analysis to be induced by the analogues and their 24-oxo metabolites in both HL-60 and U937 cells, suggesting a possible mechanism by which these analogues inhibit leukemic growth. Notably, the calcemic activity tested by injections of 1alpha,25-dihydroxy-16-ene-24-oxo-19-nor-D(3) in mice was at least 12-fold less than 1alpha,25(OH)(2)-16-ene-19-nor-D(3). Taken together, chemically synthesized 24-oxo metabolites of 1alpha,25(OH)(2)-16-ene-D(3) and 1alpha,25(OH)(2)-16-ene-19-nor-D(3) irreversibly inhibited proliferation and induced differentiation of acute myeloid leukemia cells with minimal toxicity; these compounds may have a role in the maintenance phase of therapy for acute myeloid leukemia.


Assuntos
Cálcio/sangue , Proteínas de Ciclo Celular , Colecalciferol/análogos & derivados , Colecalciferol/farmacologia , Leucemia Mieloide/tratamento farmacológico , Proteínas Supressoras de Tumor , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Colecalciferol/metabolismo , Inibidor de Quinase Dependente de Ciclina p21 , Inibidor de Quinase Dependente de Ciclina p27 , Ciclinas/biossíntese , Di-Hidroxicolecalciferóis/metabolismo , Di-Hidroxicolecalciferóis/farmacologia , Relação Dose-Resposta a Droga , Inibidores do Crescimento/metabolismo , Inibidores do Crescimento/farmacologia , Células HL-60/efeitos dos fármacos , Humanos , Leucemia Mieloide/metabolismo , Leucemia Mieloide/patologia , Proteínas Associadas aos Microtúbulos/biossíntese
17.
J Immunol ; 166(7): 4672-7, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11254727

RESUMO

We compared a potential to generate mast cells among various sources of CD34(+) peripheral blood (PB) cells in the presence of stem cell factor (SCF) with or without thrombopoietin (TPO), using a serum-deprived liquid culture system. From the time course of relative numbers of tryptase-positive and chymase-positive cells in the cultured cells grown by CD34(+) PB cells of nonasthmatic healthy individuals treated with G-CSF, TPO appears to potentiate the SCF-dependent growth of mast cells without influencing the differentiation into mast cell lineage. CD34(+) PB cells from asthmatic patients in a stable condition generated significantly more mast cells under stimulation with SCF alone or SCF+TPO at 6 wk of culture than did steady-state CD34(+) PB cells of normal controls. Single-cell culture studies showed a substantial difference in the number of SCF-responsive or SCF+TPO-responsive mast cell progenitors in CD34(+) PB cells between the two groups. In the presence of TPO, CD34(+) PB cells from asthmatic children could respond to a suboptimal concentration of SCF to a greater extent, compared with the values obtained by those of normal controls. Six-week cultured mast cells of asthmatic subjects had maturation properties (intracellular histamine content and tryptase/chymase enzymatic activities) similar to those derived from mobilized CD34(+) PB cells of nonasthmatic subjects. An increase in a potential of circulating hemopoietic progenitors to differentiate into mast cell lineage may contribute to the recruitment of mast cells toward sites of asthmatic mucosal inflammation.


Assuntos
Asma/sangue , Células-Tronco Hematopoéticas/patologia , Mastócitos/patologia , Adolescente , Antígenos CD34/biossíntese , Antígenos CD34/sangue , Asma/imunologia , Asma/patologia , Contagem de Células , Diferenciação Celular/imunologia , Divisão Celular/imunologia , Linhagem da Célula/imunologia , Células Cultivadas , Senescência Celular/imunologia , Criança , Pré-Escolar , Combinação de Medicamentos , Feminino , Fator Estimulador de Colônias de Granulócitos/farmacologia , Células-Tronco Hematopoéticas/imunologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Interleucina-6/farmacologia , Masculino , Mastócitos/imunologia , Mastócitos/metabolismo , Fator de Células-Tronco/farmacologia , Trombopoetina/farmacologia
18.
Kidney Blood Press Res ; 24(1): 18-26, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11174002

RESUMO

BACKGROUND/AIMS: The imbalance between degradation and synthesis of the glomerular extracellular matrix (ECM) causes glomerular sclerosis in various types of glomerulonephritis. We investigated the effect of prostacyclin, which is an inflammatory mediator, on the production of matrix metalloproteinase (MMP)-9 and MMP-2 in human cultured mesangial cells. The synthesis of Jun proteins and Ets-1 proteins, which are related with MMP-9 gene, was also studied. METHODS: The production of MMP-9 and MMP-2 was investigated by gelatin zymography. Western blotting was undertaken to analyze the protein synthesis of Jun and Ets-1. RESULTS: Prostacyclin inhibited the production of MMP-9 induced by phorbol ester. The inhibitory effect by prostacyclin was reversed in part by the pretreatment with an inhibitor of protein kinase A, such as H-89. Forskolin also inhibited the production of MMP-9. The production of MMP-2 was constitutionally seen and was not influenced by prostacyclin and forskolin. The synthesis of Jun protein augmented by phorbol ester was suppressed by prostacyclin. Ets-1 protein was constitutionally synthesized and was not affected by phorbol ester and prostacyclin. CONCLUSION: Prostacyclin plays an important role in inflammatory glomerular disorders by regulating the metabolism of ECM. The production of MMP-9 and MMP-2 may be under the different control pathways.


Assuntos
Carcinógenos/farmacologia , Epoprostenol/farmacologia , Mesângio Glomerular/metabolismo , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/biossíntese , Inibidores da Agregação Plaquetária/farmacologia , Acetato de Tetradecanoilforbol/farmacologia , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Ativação Enzimática , Humanos , Transdução de Sinais/efeitos dos fármacos
19.
Cell Biochem Funct ; 19(1): 43-50, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11223870

RESUMO

To determine the temporal roles of phosphatidylinositol 3-kinase (PI3-kinase) and phospholipase D (PLD) during human neutrophil activation stimulated by a chemotactic peptide, we examined the kinetics of these enzymes and related them to a neutrophil function (superoxide production). Both wortmannin and 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one (LY294002), potent and specific inhibitors of PI3-kinase, inhibit PI3-kinase activity in human neutrophils and significantly inhibit superoxide production from the early phase. Ethanol has no effect on PI3-kinase and markedly inhibits superoxide production at the late phase. Although these agents are inhibitory to different degrees, when neutrophils are simultaneously treated with ethanol and PI3-kinase inhibitors, superoxide is not produced. These results suggest that PI3-kinase and PLD play a pivotal role in the signal transduction pathway of the chemo-attractant-receptor involved neutrophil activation. These enzymes produce second messengers which are required for subsequent superoxide production in human neutrophils. NADPH oxidase is activated in a PI3-kinase-dependent manner at the early phase, and PLD activity follows it and is related to superoxide production at the late phase in human neutrophils by stimulation with FMLP.


Assuntos
N-Formilmetionina Leucil-Fenilalanina/metabolismo , Neutrófilos/enzimologia , Fosfatidilinositol 3-Quinases/fisiologia , Fosfolipase D/fisiologia , Superóxidos/metabolismo , Androstadienos/farmacologia , Cromonas/farmacologia , Relação Dose-Resposta a Droga , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Etanol/farmacologia , Humanos , Cinética , Morfolinas/farmacologia , NADPH Oxidases/metabolismo , Neutrófilos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Fatores de Tempo , Wortmanina
20.
Eur J Pediatr ; 159(12): 892-4, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11131345

RESUMO

UNLABELLED: A 12-year-old girl presented with permanent isolated proximal renal tubular acidosis (pRTA), glaucoma, band keratopathy, mild cataract and short stature. Severe metabolic acidosis was caused by the impairment of bicarbonate reabsorption in the proximal tubules and alkali therapy improved her acidaemia. A homozygous G to A transition at nucleotide 1,678 in the basolateral kidney type Na+/HCO3- (kNBC) cotransporter gene SLC4A4, which is critical in HCO3- resorption in renal proximal tubules, was identified. Her height and height velocity (HV) were very low (-4.0 SD and -4.4 SD, respectively) before alkali treatment, but both improved after initiating alkali therapy at the age of 2 years and 3 months. The patient's body height and HV were 131.5 cm (-2.7 SD) and 4.0 cm (-2.0 SD), respectively at the age of 12 years. CONCLUSION: This case demonstrates that early administration of alkali therapy and sustained correction of acidosis, even if inadequate to correct the metabolic acidosis, can markedly improves growth in permanent isolated proximal renal tubular acidosis.


Assuntos
Acidose Tubular Renal/genética , Acidose Tubular Renal/fisiopatologia , Bicarbonatos , Estatura , Proteínas de Transporte/genética , Citratos/uso terapêutico , Diuréticos/uso terapêutico , Hidroclorotiazida/uso terapêutico , Citrato de Potássio/uso terapêutico , Acidose Tubular Renal/tratamento farmacológico , Criança , Quimioterapia Combinada , Feminino , Humanos , Citrato de Sódio , Simportadores de Sódio-Bicarbonato
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA