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1.
Water Sci Technol ; 87(3): 614-619, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36789707

RESUMO

Organic sludge has recently attracted attention as a renewable energy source. While the organic matter contained in sludge can be utilized as various renewable energy sources, its nitrogen component has limited use. In this study, subcritical water treatment was conducted to recover ammonia from digested sludge. While ammonia recovered via stripping is limited to soluble components, subcritical water treatment can convert solid components and dissolved organic nitrogen sludge into ammonia. Digested sludge was treated at several reaction temperatures, reaction pressures, treatment times, and oxygen ratios to determine the ammonia generation rate. Among the conditions tested in this study, an ammonium generation rate of 84.0% was obtained at 400 °C, 10 MPa, a treatment time of 5 min, and at an oxygen ratio of 1.2.


Assuntos
Esgotos , Purificação da Água , Amônia , Temperatura , Oxigênio , Nitrogênio
2.
Nat Genet ; 11(1): 52-9, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7550314

RESUMO

Parthenogenesis in the mouse is embryonic lethal partly because of imprinted genes that are expressed only from the paternal genome. In a systematic screen using subtraction hybridization between cDNAs from normal and parthenogenetic embryos, we initially identified two apparently novel imprinted genes, Peg1 and Peg3. Peg1 (paternally expressed gene 1) or Mest, the first imprinted gene found on the mouse chromosome 6, may contribute to the lethality of parthenogenones and of embryos with a maternal duplication for the proximal chromosome 6. Peg1/Mest is widely expressed in mesodermal tissues and belongs to the alpha/beta hydrolase fold family. A similar approach with androgenones can be used to identify imprinted genes that are expressed from the maternal genome only.


Assuntos
Mapeamento Cromossômico , DNA Complementar/genética , Genes Letais , Impressão Genômica/genética , Hidrolases/genética , Camundongos/genética , Partenogênese/genética , Técnica de Subtração , Sequência de Aminoácidos , Animais , Sequência de Bases , Desenvolvimento Embrionário e Fetal/genética , Feminino , Morte Fetal/genética , Regulação da Expressão Gênica no Desenvolvimento , Hidrolases/biossíntese , Masculino , Camundongos/embriologia , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Dados de Sequência Molecular , Muridae/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
3.
Nat Genet ; 12(2): 186-90, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8563758

RESUMO

Genetic and embryological studies in the mouse demonstrated functional differences between parental chromosomes during development. This is due to imprinted genes whose expression is dependent on their parental origin. In a recent systematic screen for imprinted genes, we detected Peg3 (paternally expressed gene 3). Peg3 is not expressed in parthenogenones. In interspecific hybrids, only the paternal copy of the gene is expressed in the embryos, individual tissues examined in d9.5-13.5 embryos, neonates and adults. Peg3 mRNA is a 9 kb transcript encoding an unusual zinc finger protein with eleven widely spaced C2H2 type motifs and two groups of amino acid repeats. Peg3 is expressed in early somites, branchial arches and other mesodermal tissues, as well as in the hypothalamus. Peg3 maps to the proximal region of chromosome 7. Consistent with our findings, maternal duplication of the proximal chromosome 7 causes neonatal lethality. This region is syntenic with human chromosome 19q13.1-13.3 (refs 10,11), where the genes for myotonic dystrophy and a putative tumour suppressor gene are located.


Assuntos
Impressão Genômica/genética , Proteínas Quinases , Proteínas/genética , Fatores de Transcrição , Dedos de Zinco , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos , Sequência de Bases , Química Encefálica , Bandeamento Cromossômico , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Hibridização in Situ Fluorescente , Fatores de Transcrição Kruppel-Like , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Muridae/embriologia , RNA Mensageiro/genética , Análise de Sequência de DNA
4.
Phys Rev Lett ; 108(20): 206803, 2012 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-23003165

RESUMO

The experimental evidence is presented of the topological insulator state in PbBi2Te4. A single surface Dirac cone is observed by angle-resolved photoemission spectroscopy with synchrotron radiation. Topological invariants Z2 are calculated from the ab initio band structure to be 1;(111). The observed two-dimensional isoenergy contours in the bulk energy gap are found to be the largest among the known three-dimensional topological insulators. This opens a pathway to achieving a sufficiently large spin current density in future spintronic devices.

5.
Int J Oncol ; 32(2): 397-403, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18202762

RESUMO

NPe6 is a novel second-generation photosensitizer used for photodynamic therapy (PDT). PDT using NPe6 and diode laser (664 nm) induces cell death, inflammatory reactions, immunological responses and damage to the microvasculature. In this study, we evaluated the influence of the immunological responses and of enhanced angiogenesis on the anti-tumor effect of NPe6-PDT using cytokine-overexpressing Lewis lung carcinoma (LLC), LLC-IL-2 cells both in vitro and in vivo. We showed by DNA microarray analysis in vitro that IL-2 and GADD-45alpha (growth arrest and DNA damage 45 alpha) mRNA expressions were induced by 3 h after NPe6-PDT applied at a dose killing 90% of the cells (LD90). IL-2-overexpressing cells (LLC/IL-2 cells) were resistant to the loss of clonogenicity as compared to the parental LLC cells in vitro. Furthermore, in female C57BL/6 mice, NPe6-PDT produced a cure rate of 66.7% in LLC tumors, whereas the cure rate was only 16.6% in LLC/IL-2 tumors, and overexpression of IL-2 caused failure of NPe6-PDT, with tumor recurrence, in vivo. These results suggest that IL-2 expression may play an unfavorable role in attenuation of the antitumor effect of NPe6-PDT. It has been reported that the expression of vascular endothelial growth factor (VEGF), in particular, may cause tumor recurrence after PDT and exert unfavorable effect in relation to attenuate the anti-tumor activity of PDT. Results of immunohistochemical analysis of LLC/IL-2 tumors have revealed that the expressions of GADD-45alpha and VEGF are induced in these tumors after PDT, and in particular, 12 h after PDT, the expression levels were much higher as compared with those in the LLC tumors. The results of our studies using in vitro and in vivo models suggest that the cell death caused by PDT was inhibited by induction of GADD-45alpha expression and that tumor recurrence was promoted by the enhancement of VEGF expression mediated by IL-2 upregulation. Therefore, it is speculated that the use of an IL-2 inhibitor may improve the efficacy of NPe6-PDT.


Assuntos
Proteínas de Ciclo Celular/biossíntese , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Interleucina-2/biossíntese , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas Nucleares/biossíntese , Fotoquimioterapia/métodos , Porfirinas/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Carcinoma Pulmonar de Lewis , Feminino , Interleucina-2/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fármacos Fotossensibilizantes/farmacologia , Recidiva , Fator A de Crescimento do Endotélio Vascular/biossíntese
6.
J Neurol Neurosurg Psychiatry ; 79(12): 1324-6, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18550630

RESUMO

BACKGROUND: In elderly people, chronic dizziness is endemic. However, chronic dizziness of unknown origin is difficult to assess. OBJECTIVE: To investigate whether mild unrecognised benign paroxysmal positional vertigo (BPPV) is a cause of isolated chronic dizziness in the elderly. PATIENTS AND METHODS: The prevalence of extremely weak, horizontal, direction changing apogeotropic positional nystagmus (HAPN) that had not been detected by conventional examination was evaluated in 200 patients with isolated chronic dizziness and in 155 age matched control subjects without dizziness. RESULTS: A high prevalence of weak HAPN was found in patients with isolated chronic dizziness (98/200 (49.0%)) compared with the prevalence in control subjects without dizziness (25/155 (16.1%); p<0.0001). Symptoms improved in some patients by daily positional exercise for BPPV. CONCLUSION: Because BPPV is the most common cause of dizziness in the elderly, and HAPN is a characteristic of horizontal canal BPPV, our findings suggest that mild persistent BPPV is a possible cause of chronic dizziness of otherwise unknown origin in the elderly.


Assuntos
Tontura/complicações , Tontura/diagnóstico , Nistagmo Fisiológico , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Tontura/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurologia/métodos , Prevalência , Resultado do Tratamento , Vertigem , Testes de Função Vestibular/métodos
7.
Food Chem Toxicol ; 46(3): 1119-24, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18155344

RESUMO

Ellagic acid is a phenolic acid compound, used as a food additive for its antioxidative properties. Because of its chemical characteristics, use is also to be expected in cosmetics. The present 90-day subchronic toxicity study was performed in F344 rats at dose levels of 0, 1.25, 2.5 and 5% in powdered basal diet, with actual doses of 9.4, 19.1, 39.1 g/kg b.w., respectively, in males, and 10.1, 20.1, 42.3 g/kg b.w. in females. No mortality or treatment-related clinical signs were observed throughout the experimental period. Body weight gain was significantly reduced from weeks 3 (5% group), 6 (2.5% group) and 7 (1.25% group) to the end of the experiment (except week 8 in the lowest group) in the treated females, the final body weights being decreased in the 5% (92.5%), 2.5% (94.2%) and 1.25% (94.8%) treated groups as compared to the control. Changes in MCV and serum AST, ALP, Ca, Cl and P were sporadically observed, but these were not considered to be treatment-related alterations. There were no obvious histopathological changes in any of the groups. The no-observed-effect level (NOEL) was estimated to be 5% (3011 mg/kg b.w./day) for males and the no-observed-adverse-effect level (NOAEL) and NOEL in females were estimated to be 5% (3254 mg/kg b.w./day) and <1.25% (778 mg/kg b.w./day), respectively.


Assuntos
Antioxidantes/toxicidade , Ácido Elágico/toxicidade , Aditivos Alimentares/toxicidade , Animais , Análise Química do Sangue , Peso Corporal/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Feminino , Testes Hematológicos , Masculino , Nível de Efeito Adverso não Observado , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Endogâmicos F344
8.
Transplant Proc ; 40(2): 574-7, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18374132

RESUMO

We directly injected porcine donor mesenchymal stem cells (MSC) into murine bone marrow (BM) cavities to examine the effects of intra-BM cotransplantation of MSC in pig-to-NOD/SCID mouse bone marrow transplantation (BMT) on xenogeneic engraftment. Porcine MSC prepared by aspiration of iliac BM of miniature swine were identified as CD90+CD29+CD45-CD31- and shown to differentiate into osteoblastocytes and adipocytes. A few weeks after expansion, MSC (1 x 10(6) cells/mouse) were directly injected with BM cells (30 x 10(6) cells/mouse) obtained from vertebrae through a microsyringe into BM cavities of both tibiae of NOD/SCID mice after 3-Gy total body irradiation. Controls were injected with only BM cells. Porcine chimerisms of BM cells of tibiae (injection site) and of femurs (non-injection site) in recipient mice were evaluated with porcine and murine cell markers using FACS. The chimerism of porcine class I+ cells at the injection site in the MSC group and the controls were 3.45%, 1.43%, and 0.17%, and 2.27%, 0.81%, and 0.1% at 1, 3, and 6 weeks, respectively. The chimerism at the noninjection site in the MSC group and the controls were 0.21%, 1.34%, and 0.11%, and 0.06%, 0.42%, and 0.09% at 1, 3, and 6 weeks, respectively. The total chimerisms of injection site in the MSC group to 6 weeks were significantly higher than those in the control group (1.60% vs 0.99%; P < .05), whereas the chimerism of the noninjection site in MSC group was remarkably higher at 3 weeks. In conclusion, intra-BM cotransplantation of porcine donor MSC in pig-to-NOD/SCID mouse BMT improved short-term xenogeneic engraftment, presumably due to humoral factors.


Assuntos
Transplante de Medula Óssea/imunologia , Sobrevivência de Enxerto/fisiologia , Transplante de Células-Tronco Mesenquimais , Transplante Heterólogo/fisiologia , Animais , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Suínos
9.
Dalton Trans ; 47(8): 2575-2580, 2018 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-29384546

RESUMO

Silver bismuth diselenide (AgBiSe2) has attracted much attention as an efficient thermoelectric material, owing to its intrinsically low lattice thermal conductivity. While samples synthesized using a solid-state reaction showed n-type conductivity and their dimensionless figure of merit (ZT) reached ∼1 by electron doping, theoretical calculations predicted that a remarkably high thermoelectric performance can be achieved in p-type AgBiSe2. In this paper, we present the effect of Te substitution on the crystal structure and thermoelectric properties of AgBiSe2, expecting p-type conductivity due to the shallowing of the energy potential of the valence band. We found that all AgBiSe2-xTex (x = 0-0.8) prepared using a solid-state reaction exhibits n-type conductivity from 300 to 750 K. The room-temperature lattice thermal conductivity decreased to as low as 0.3 W m-1 K-1 by Te substitution, which was qualitatively described using the point defect scattering model for the solid solution. We show that ZT reaches ∼0.6 for x = 0.8 at a broad range of temperatures, from 550 to 750 K, due to the increased power factor, although the carrier concentration has not been optimized yet.

10.
Oncol Rep ; 18(3): 679-83, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17671719

RESUMO

ATX-s10-Na(II) is a novel second-generation photo-sensitizer for photodynamic therapy (PDT). PDT using ATX-s10 and diode laser (670 nm) induces an apoptotic response, inflammatory reaction, immune reaction and damage to the microvasculature. In particular, the vascular shut-down effect plays an important role in the anti-tumor activity of ATX-s10-PDT. It has been reported that PDT induces hypoxia and expression of the vascular endothelial growth factor (VEGF) via the hypoxia-inducible factor 1 (HIF1)-alpha pathway. We hypothesized that the expression of VEGF may cause tumor recurrence after PDT and exert unfavorable effect against the anti-tumor activity of ATX-s10-PDT. In this study, we showed by DNA microarray analysis in vitro that VEGF mRNA expression was induced 3 h after laser irradiation in ATX-s10-PDT. We compared the anti-tumor activity of ATX-s10-PDT against lung cancer cell lines SBC-3 and SBC-3/VEGF, the latter overexpressing VEGF; there was no significant difference in the sensitivity to the PDT between the two cell lines as assessed by clonogenic assay. Furthermore, no statistically significant difference in the anti-tumor effect of PDT, as measured by tumor cures, was found between SBC-3 and SBC-3/VEGF tumors in female Balb/c-nu/nu nude mice in vivo. In conclusion, ATX-s10-PDT may prevent tumor recurrence despite induction of VEGF and promotion of tumor angiogenesis, which are known to enhance tumor proliferation and survival.


Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/uso terapêutico , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Linhagem Celular Tumoral , DNA de Neoplasias/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Neoplasias Pulmonares , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Análise de Sequência com Séries de Oligonucleotídeos , RNA/genética , RNA/isolamento & purificação
11.
Nat Biotechnol ; 18(10): 1086-90, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11017048

RESUMO

For introducing regions of human chromosomes greater than a megabase into cells or animals, we have developed a chromosome-cloning system in which defined regions of human chromosomes can be cloned into a stable human minichromosome vector in homologous recombination-proficient chicken DT40 cells. The stable minichromosome vector allowed a 10 Mb-sized region of the mitotically unstable human chromosome 22 to be stably maintained in mouse embryonic stem (ES) cells, and in mice. Furthermore, we demonstrated functional expression of human genes from the HAC in mice. This study describes a stable cloning and expression system for greater than megabase-sized regions of human chromosomes.


Assuntos
Cromossomos Artificiais Humanos/genética , Clonagem Molecular/métodos , DNA Recombinante/genética , Animais , Linhagem Celular , Galinhas , Quimera/genética , Quimera/imunologia , Cromossomos Humanos Par 22/genética , Citometria de Fluxo , Expressão Gênica , Fator Estimulador de Colônias de Granulócitos/sangue , Fator Estimulador de Colônias de Granulócitos/imunologia , Humanos , Hibridomas/imunologia , Cadeias Leves de Imunoglobulina/genética , Cadeias Leves de Imunoglobulina/imunologia , Hibridização in Situ Fluorescente , Camundongos , Mitose/genética , Recombinação Genética/genética , Homologia de Sequência do Ácido Nucleico , Células-Tronco , Telômero/genética , Fatores de Tempo
12.
Theriogenology ; 67(1): 127-33, 2007 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17070901

RESUMO

Considerable progress has been made in methods for production of transgenic livestock; beginning with pronuclear microinjection over 20 years ago. New methods, including the use of viral vectors, sperm-mediated gene transfer and somatic cell cloning, have overcome many of the limitations of pronuclear microinjection. It is now possible to not only readily make simple insertional genetic modifications, but also to accomplish, more complex, homozygous gene targeting and artificial chromosome transfer in livestock.


Assuntos
Animais Domésticos/genética , Animais Geneticamente Modificados , Biotecnologia/tendências , Clonagem Molecular , Técnicas de Transferência de Genes/veterinária , Animais , Animais Domésticos/fisiologia , Bovinos/genética , Bovinos/fisiologia , Feminino , Cabras/genética , Cabras/fisiologia , Masculino , Seleção Genética , Ovinos/genética , Ovinos/fisiologia , Suínos/genética , Suínos/fisiologia
13.
Rev Sci Instrum ; 88(8): 085111, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28863664

RESUMO

In this study, we developed a user-friendly automatic powder diffraction measurement system for Debye-Scherrer geometry using a capillary sample at beamline BL02B2 of SPring-8. The measurement system consists of six one-dimensional solid-state (MYTHEN) detectors, a compact auto-sampler, wide-range temperature control systems, and a gas handling system. This system enables to do the automatic measurement of temperature dependence of the diffraction patterns for multiple samples. We introduced two measurement modes in the MYTHEN system and developed new attachments for the sample environment such as a gas handling system. The measurement modes and the attachments can offer in situ and/or time-resolved measurements in an extended temperature range between 25 K and 1473 K and various gas atmospheres and pressures. The results of the commissioning and performance measurements using reference materials (NIST CeO2 674b and Si 640c), V2O3 and Ti2O3, and a nanoporous coordination polymer are presented.

14.
Neuropharmacology ; 50(8): 909-16, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16504219

RESUMO

L-3,4-dihydroxyphenylalanine (DOPA) is a neurotransmitter candidate. To map the DOPAergic system functionally, DOPA-induced c-Fos expression was detected under inhibition of central aromatic L-amino acid decarboxylase (AADC). In rats treated with a central AADC inhibitor, DOPA significantly increased the number of c-Fos-positive nuclei in the paraventricular nuclei (PVN) and the nucleus tractus solitarii (NTS), and showed a tendency to increase in the supraoptic nuclei (SON), but not in the striatum. On the other hand, DOPA with a peripheral AADC inhibitor elevated the level of c-Fos-positive nuclei in the four regions, suggesting that DOPA itself induces c-Fos expression in the SON, PVN and NTS. In rats treated with 6-hydroxydopamine (6-OHDA) to lesion the nigrostriatal dopamine (DA) pathway, DOPA significantly induced c-Fos expression in the four regions under the inhibition of peripheral AADC. However, under the inhibition of central AADC, DOPA did not significantly increase the number of c-Fos-positive nuclei in the four regions, suggesting that DOPA at least in part induces c-Fos expression through its conversion to DA. It was likely that the 6-OHDA lesion enhanced the response to DA, but attenuated that to DOPA itself. In conclusion, we proposed that the SON, PVN and NTS include target sites for DOPA itself.


Assuntos
Descarboxilases de Aminoácido-L-Aromático/metabolismo , Sistema Nervoso Central/efeitos dos fármacos , Dopaminérgicos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Levodopa/farmacologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Animais , Benserazida/farmacologia , Contagem de Células/métodos , Interações Medicamentosas , Inibidores Enzimáticos/farmacologia , Lateralidade Funcional , Hidrazinas/farmacologia , Imuno-Histoquímica/métodos , Masculino , Feixe Prosencefálico Mediano/lesões , Atividade Motora/efeitos dos fármacos , Oxidopamina/toxicidade , Ratos , Ratos Sprague-Dawley
15.
Food Chem Toxicol ; 44(1): 138-45, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16095791

RESUMO

Dunaliella carotene, extracted from dunaliella alga (Dunaliella bardawil or Dunaliella salina), for use as a food-coloring agent, has beta-carotene as its mainly constituent. As there have been no reports of toxicological evaluation, a 90-day subchronic toxicity study was here performed in F344 rats at dose levels of 0 (control), 0.63%, 1.25%, 2.5% and 5% in powdered basal diet. The average daily intakes of dunaliella carotene were 352, 696, 1420 and 2750 mg/kg/day, respectively, for males, and 370, 748, 1444 and 2879 mg/kg/day for females. No mortality or treatment-related clinical signs were observed throughout the experimental period in any of the groups. Body weight gain was slightly but significantly (p < 0.05) reduced from week 5 to the end of the experiment in 2.5% and 5% males. Increased PLT were observed in 1.25% and 5% males, and 2.5% and 5% females. Significant elevations or tendencies for increase in serum T. Cho and Ca were observed in all treated males and females, with clear dose-dependence in males. Organ weight measurement and histopathological observation revealed no toxicological changes. Based on growth suppression, no-observed-adverse-effect-levels (NOAELs) were estimated to be 1.25% (696 mg/kg/day) for males and 5% (2879 mg/kg/day) for females. As increases in serum Ca were observed in the lowest group in both sexes, a no-observed-effect level (NOEL) could not be determined in this study.


Assuntos
Clorófitas/química , Corantes de Alimentos/toxicidade , beta Caroteno/toxicidade , Administração Oral , Animais , Plaquetas/efeitos dos fármacos , Cálcio/sangue , Colesterol/sangue , Relação Dose-Resposta a Droga , Feminino , Corantes de Alimentos/análise , Masculino , Nível de Efeito Adverso não Observado , Extratos Vegetais/análise , Extratos Vegetais/toxicidade , Contagem de Plaquetas , Ratos , Ratos Endogâmicos F344 , Testes de Toxicidade , Aumento de Peso/efeitos dos fármacos , beta Caroteno/análise
16.
Cancer Res ; 52(17): 4634-41, 1992 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-1324788

RESUMO

We have recently demonstrated that bufalin is a new potent inducer of the differentiation of human myeloid leukemia cells. The present work was carried out to examine further the effect of bufalin on the growth and characteristics of human leukemia-derived cell lines U937, ML1, and HL60. At concentrations of 5-10 nM, bufalin decreased the growth of ML1 cells preferentially at the G2 phase and U937 cells at the S and G2 phases of the cell cycle. Bufalin, under these conditions, induced the differentiation of U937, ML1, and HL60 cells to monocyte/macrophage-like cells by measuring the expression of various differentiation markers, as assessed by morphology and histochemistry, and ability to phagocytose latex particles, to reduce nitroblue tetrazolium, and to develop Fc receptors. U937 and ML1 cells started to differentiate at 4 and 6 h, respectively, after treatment with 10 nM bufalin and showed maximum differentiation 72 h later. At present, a mechanism for the bufalin-mediated induction of the differentiation of these human leukemia cells remains to be determined. The combination of bufalin with all-trans retinoic acid, 1 alpha,25-dihydroxyvitamin D3, 4'-demethylepipodophyllotoxin ethylidene-beta-D-glucoside (VP16), or human gamma-interferon synergistically induced the differentiation of HL60 and U937 cells. A similar effect on ML1 cells was observed with the combination of bufalin with VP16 or human rTNF-alpha. These results suggest that bufalin in combination with VP16, all-trans retinoic acid, 1 alpha,25-dihydroxyvitamin D3, rTNF-alpha, or gamma-interferon may be very useful in the differentiation of human leukemia.


Assuntos
Bufanolídeos/administração & dosagem , Diferenciação Celular/efeitos dos fármacos , Leucemia Mieloide/patologia , Macrófagos/citologia , Monócitos/citologia , Antineoplásicos/administração & dosagem , Divisão Celular/efeitos dos fármacos , Citocinas/administração & dosagem , Digitoxigenina/administração & dosagem , Esquema de Medicação , Sinergismo Farmacológico , Humanos , Técnicas In Vitro , Ouabaína/administração & dosagem , ATPase Trocadora de Sódio-Potássio/metabolismo , Células Tumorais Cultivadas/citologia , Vitaminas/administração & dosagem
17.
Oncogene ; 15(6): 677-83, 1997 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-9264408

RESUMO

The Pebpb2/Cbfb gene encodes the non-DNA binding beta subunit of the heterodimeric transcription factor, PEBP2/CBF, and has been implicated in a subtype of human acute myeloid leukemia, as well as being indispensable for the development of definitive hematopoiesis in the murine fetal liver. By examining a subcellular localization of the PEBP2beta/CBFbeta protein in tissue culture cells, we could reveal an additional aspect of the protein other than to be a subunit of a transcription factor. Immunoblot and immunocytochemical staining showed that PEBP2beta/CBFbeta was mostly present in the cytoplasm. This PEBP2beta/CBFbeta was free from its DNA-binding partner, the alpha subunit of PEBP2/CBF, as judged by the electrophoretic mobility shift assays. Furthermore, a significant amount of PEBP2beta/CBFbeta was retained in the cytoskeleton preparation after detergent extraction of the cells and was found by double immunofluorescence to colocalize with the F-actin on stress fibers and the vinculin in membrane processes. Thus, the present study extends PEBP2beta/CBFbeta to be a cytoskeleton-affinitive as well as nuclear protein. The implications of these results are discussed.


Assuntos
Citoplasma/metabolismo , Citoesqueleto/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/metabolismo , Células 3T3 , Actinas/metabolismo , Animais , Western Blotting , Núcleo Celular/metabolismo , Células Cultivadas , Subunidade beta de Fator de Ligação ao Core , Proteínas de Ligação a DNA/imunologia , Humanos , Imuno-Histoquímica , Camundongos , Microscopia de Fluorescência , Fator de Transcrição AP-2 , Fatores de Transcrição/imunologia , Transfecção , Vinculina/metabolismo
18.
Biochim Biophys Acta ; 875(1): 115-21, 1986 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-3079639

RESUMO

The uptake and degradation of GM1 ganglioside (GM1) and asialoGM1 ganglioside (GA1) were studied in cultured fibroblasts from normal individuals and patients with beta-galactosidase deficiency, using the lipid-loading test. The glycolipids were incorporated from the media into the fibroblasts and the terminal galactose was hydrolyzed in normal cells. The hydrolysis rates of GA1 were 80-86% of normal on the 3rd day after loading, while GM1 was hydrolyzed slowly; 35-54% on the 14th day. In infantile GM1 gangliosidosis and I-cell disease, little GM1 and GA1 was hydrolyzed on any day of culture, while fibroblasts from patients with adult GM1 gangliosidosis, Morquio disease type B and galactosialidosis hydrolyzed the lipids at nearly normal rates. The intracellular accumulation of the glycolipids, on the basis of protein content, was abnormally high in the case of infantile GM1 gangliosidosis and I-cell disease, but normal in the other disorders examined. These observations indicate that the in situ metabolism of GM1 and GA1 is probably normal in fibroblasts from patients with adult GM1 gangliosidosis, Morquio disease type B and galactosialidosis, although in vitro beta-galactosidase activities in these disorders are very low. The results are compatible with findings that GM1 and GA1 do not accumulate in the somatic organs of patients with adult GM1 gangliosidosis and galactosialidosis. In I-cell disease, however, the results of the loading test did not agree with the finding that there is little accumulation of glycolipids in postmortem tissues.


Assuntos
Gangliosídeo G(M1)/metabolismo , Galactosidases/deficiência , Glicoesfingolipídeos/metabolismo , beta-Galactosidase/deficiência , Adulto , Animais , Encéfalo , Bovinos , Células Cultivadas , Fibroblastos/metabolismo , Gangliosidoses/metabolismo , Humanos , Lactente , Cinética , Valores de Referência , Trítio
19.
Biochim Biophys Acta ; 879(2): 215-20, 1986 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-3094585

RESUMO

The metabolism of galactosylceramide was investigated in normal and twitcher mice, an animal model for human globoid cell leukodystrophy. The findings were compared with data obtained on human tissues. In vitro studies demonstrated that there were two genetically distinct enzymes that hydrolyze galactosylceramide: galactosylceramidase I and II. The former was deficient in the twitcher, while the latter was intact. beta-Galactosidase preparations purified from normal mouse liver possessed the activity to hydrolyze galactosylceramide when the assay conditions for galactosylceramidase II was used. Therefore, galactosylceramidase II was considered to be identical to GM1 ganglioside beta-galactosidase. In contrast to the human enzyme, the murine beta-galactosidase had a relatively high Km value toward galactosylceramide. The galactosylceramide-loading test demonstrated that the twitcher fibroblasts hydrolyzed the lipid at lower rates than seen in cases of human globoid cell leukodystrophy fibroblasts. These differences in galactosylceramidase II between murine and human tissues suggest that galactosylceramide accumulates in twitcher mice but not in humans with globoid cell leukodystrophy, even though galactosylceramidase I is genetically deficient in both human and this mouse model.


Assuntos
Cerebrosídeos/metabolismo , Galactosilceramidas/metabolismo , Leucodistrofia de Células Globoides/metabolismo , Camundongos Mutantes Neurológicos/metabolismo , Animais , Galactosilceramidase/metabolismo , Humanos , Hidrólise , Técnicas In Vitro , Leucodistrofia de Células Globoides/enzimologia , Fígado/enzimologia , Camundongos , beta-Galactosidase/metabolismo
20.
Biochim Biophys Acta ; 677(2): 280-6, 1981 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-7295797

RESUMO

The activities of mitochondrial type A and B monoamine oxidase were determined in the liver of rats fed a diet containing 2-acetylaminofluorene (AAF). Three days after the initiation of AAF-feeding, there was a significant decrease of type B monoamine oxidase activity without affect on type A enzyme. The decreased activity of type B monoamine oxidase, which reached a minimum after three weeks, was sustained for as long as AAF-feeding was continued. Sex-related difference in response to AAF was seen in the rat with respect to the onset and the intensity of the decreased type B monoamine oxidase activity, male rats being more sensitive to the carcinogen than female rats. In contrast to the in vivo effect, AAF showed a potent inhibitory effect on type A monoamine oxidase, rather than on type B enzyme, when added in vitro. The pI50 values were estimated to be 7.5 against type A monoamine oxidase and 4.1 against type B enzyme, respectively. The in vitro inhibition of both types of monoamine oxidase by AAF was competitive. The Ki values for AAF were calculated to be 9.51 x 10(-9)M for type A monoamine oxidase and 1.30 x 10(-5)M for type B enzyme, respectively. In accordance with the potent inhibitory effect of AAF on type A monoamine oxidase in vitro, a single administration of the carcinogen, at a dose of 50 mg/kg, resulted in a marked and temporal decrease of the enzyme activity in the mitochondria of male rat liver. Recovery of the decreased type B monoamine oxidase activity was slow, and the enzyme activity did not return to control levels, even if rats were fed the basal diet for 2 or 4 weeks after the cessation of AAF-feeding


Assuntos
2-Acetilaminofluoreno/toxicidade , Mitocôndrias Hepáticas/efeitos dos fármacos , Inibidores da Monoaminoxidase , Monoaminoxidase/metabolismo , Animais , Feminino , Técnicas In Vitro , Neoplasias Hepáticas Experimentais/induzido quimicamente , Masculino , Mitocôndrias Hepáticas/enzimologia , Ratos , Fatores Sexuais
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