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1.
Glycoconj J ; 34(1): 85-94, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27658397

RESUMO

An N-acetyl sugar-binding lectin (termed iNoL) displaying cytotoxic activity against human cancer cells was isolated from the slipper lobster Ibacus novemdentatus (family Scyllaridae). iNoL recognized monosaccharides containing N-acetyl group, and glycoproteins (e.g., BSM) containing oligosaccharides with N-acetyl sugar. iNoL was composed of five subunits (330, 260, 200, 140, and 30 kDa), which in turn consisted of 70-, 40-, and 30-kDa polypeptides held together by disulfide bonds. Electron microscopic observations and gel permeation chromatography indicated that iNoL was a huge (500-kDa) molecule and had a polygonal structure under physiological conditions. iNoL displayed cytotoxic (apoptotic) effects against human cancer cell lines MCF7 and T47D (breast), HeLa (ovarian), and Caco2 (colonic), through incorporation (internalization) into cells. The lectin was transported into lysosomes via endosomes. Its cytotoxic effect and incorporation into cells were inhibited by the co-presence of N-acetyl-D-mannosamine (ManNAc). Treatment of HeLa cells with iNoL resulted in DNA fragmentation and chromatin condensation, through activation of caspase-9 and -3. In summary, the novel crustacean lectin iNoL is incorporated into mammalian cancer cells through glycoconjugate interaction, and has cytotoxic (apoptotic) effects.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Decápodes/química , Endocitose , Lectinas/farmacologia , Animais , Antineoplásicos/química , Células CACO-2 , Caspase 3/metabolismo , Caspase 9/metabolismo , Endossomos/efeitos dos fármacos , Endossomos/metabolismo , Glicoproteínas/metabolismo , Células HeLa , Humanos , Lectinas/química , Lectinas/toxicidade , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Células MCF-7 , Ligação Proteica
2.
J Periodontal Res ; 52(3): 594-602, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28233905

RESUMO

BACKGROUND AND OBJECTIVE: Periodontal disease is a chronic inflammatory disease caused by bacterial infection that can lead to tooth loss. Gingival crevicular fluid can be collected easily and noninvasively. We previously discovered the presence of apolipoprotein B (apoB), the main constituent of low-density lipoprotein, and oxidized low-density lipoprotein (oxLDL) in the gingival crevicular fluid of healthy subjects. In this study, we investigated whether periodontal conditions affect the levels of apoB and oxLDL in gingival crevicular fluid. MATERIAL AND METHODS: The study population comprised 11 patients with chronic periodontitis. A pair of gingival crevicular fluid samples was collected from each patient at a healthy site and at a site with periodontitis (baseline samples). Thereafter, gingival crevicular fluid samples were collected from the same patients again at 4 and 8 wk after scaling and root planing (SRP). The levels of apoB, oxLDL, protein and cytokines in gingival crevicular fluid, in addition to gingival crevicular fluid volume, were measured. RESULTS: At baseline, the levels of apoB and oxLDL in gingival crevicular fluid were higher at the sites with periodontitis than at the healthy sites. The levels of apoB and oxLDL at periodontal sites decreased after SRP. The level of oxLDL in gingival crevicular fluid correlated well with the probing pocket depth. The oxLDL : apoB ratio in gingival crevicular fluid was significantly higher than that in plasma. CONCLUSIONS: The levels of apoB and oxLDL in gingival crevicular fluid change according to the periodontal tissue conditions.


Assuntos
Apolipoproteínas B/análise , Periodontite Crônica/metabolismo , Líquido do Sulco Gengival/química , Lipoproteínas LDL/análise , Idoso , Periodontite Crônica/terapia , Citocinas/análise , Índice de Placa Dentária , Raspagem Dentária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice Periodontal , Aplainamento Radicular
3.
Colorectal Dis ; 17(11): 1002-6, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25891199

RESUMO

AIM: Several procedures have been described for rectovaginal fistula with a wide range of success, but there is little information on the long-term outcome. The aim of the present study was to investigate the long-term outcome after transvaginal anterior levatorplasty (ALP) for intractable rectovaginal fistula. METHOD: Data of 16 consecutive patients undergoing transvaginal ALP with fistulectomy and closure of the rectum and vagina between 1998 and 2011 were prospectively recorded and retrospectively investigated to study the long-term outcome. RESULTS: Birth injury (n = 7), low anterior resection for rectal cancer (n = 3), pouch surgery for ulcerative colitis (n = 2) and a procedure for prolapse and haemorrhoids (n = 2) were the main causes of the fistula. Nine patients had a covering stoma before surgery. All patients underwent ALP, with a covering stoma in two patients. Infection occurred in one patient and wound rupture after surgery in another patient. These patients underwent reoperation by ALP. All fistulae had healed at a median follow-up of 84 (8-193) months after initial surgery or stoma closure. CONCLUSION: Transvaginal ALP is effective for the treatment of mid or low rectovaginal fistula. The results show that a graft is not necessary regardless of whether or not previous surgery has been performed.


Assuntos
Cirurgia Endoscópica por Orifício Natural/métodos , Procedimentos de Cirurgia Plástica/métodos , Fístula Retovaginal/cirurgia , Reto/cirurgia , Retalhos Cirúrgicos , Adulto , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Vagina
4.
Glycoconj J ; 31(2): 171-84, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24271942

RESUMO

SBL/RC-RNase was originally isolated from frog (Rana catesbeiana) oocytes and purified as a novel sialic acid-binding lectin (SBL) that displayed strong anti-cancer activity. SBL was later shown to be identical to a ribonuclease (RC-RNase) from oocytes of the same species. The administration of SBL/RC-RNase induced apoptosis (with nuclear condensation and DNA fragmentation) in mouse leukemia P388 cells but did not kill umbilical vein endothelial or fibroblast cells derived from normal tissues. The cytotoxic activity of SBL/RC-RNase was inhibited by desialylation of P388 cells and/or the co-presence of free bovine submaxillary mucin. FACS analysis showed that SBL/RC-RNase was incorporated into cells after attachment to cholesterol-rich microdomains. Addition of the cholesterol remover methyl-ß-cyclodextrin reduced SBL/RC-RNase-induced apoptosis. Apoptosis occurred through the caspase-3 pathway following activation of caspase-8 by SBL/RC-RNase. A heat shock cognate protein (Hsc70) and a heat shock protein (Hsp70) (each 70 kDa) on the cell membrane were shown to bind to SBL/RC-RNase by mass spectrometric and flow cytometric analyses. Quercetin, an inhibitor of Hsc70 and Hsp70, significantly reduced SBL/RC-RNase-induced apoptosis. Taken together, our findings suggest that sialyl-glycoconjugates present in cholesterol-rich microdomains form complexes with Hsc70 or Hsp70 that act as triggers for SBL/RC-RNase to induce apoptosis through a pathway involving the activation of caspase-3 and caspase-8.


Assuntos
Apoptose/fisiologia , Colesterol/química , Glicoconjugados/metabolismo , Microdomínios da Membrana/química , Oócitos/enzimologia , Ribonucleases/metabolismo , Animais , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular , Proteínas de Choque Térmico HSC70/metabolismo , Proteínas de Choque Térmico HSP72/metabolismo , Leucemia P388 , Microdomínios da Membrana/metabolismo , Camundongos , Ácido N-Acetilneuramínico/química , Rana catesbeiana
5.
Tech Coloproctol ; 17(4): 437-40, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23292111

RESUMO

BACKGROUND: The aim of the present study was to classify the short-term outcomes of local correction of stoma prolapse with a stapler device. METHODS: The medical records of 11 patients undergoing local correction of stoma prolapse using a stapler device were retrospectively reviewed. RESULTS: No mortality or morbidity was observed after the surgery. Median operative time was 35 min (range 15-75 min), and blood loss was minimal. Median duration of follow-up was 12 months (range 6-55 months). One of the 11 patients had a recurrent stoma prolapse. CONCLUSIONS: This technique can be a feasible, safe and minimally invasive correction procedure for stoma prolapse.


Assuntos
Neoplasias Colorretais/cirurgia , Colostomia/efeitos adversos , Grampeadores Cirúrgicos , Prolapso Visceral/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Colectomia/métodos , Doenças do Colo/cirurgia , Neoplasias Colorretais/patologia , Colostomia/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação/métodos , Estudos Retrospectivos , Medição de Risco , Fatores de Tempo , Resultado do Tratamento , Prolapso Visceral/etiologia
6.
Heredity (Edinb) ; 108(3): 242-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21792227

RESUMO

Transmission ratio distortion (TRD), in which one allele is transmitted more frequently than the opposite allele, is presumed to act as a driving force in the emergence of a reproductive barrier. TRD acting in a sex-specific manner has been frequently observed in interspecific and intraspecific hybrids across a broad range of organisms. In contrast, sex-independent TRD (siTRD), which results from preferential transmission of one of the two alleles in the heterozygote through both sexes, has been detected in only a few plant species. We previously reported an S(6) locus-mediated siTRD, in which the S(6) allele from an Asian wild rice strain (Oryza rufipogon) was transmitted more frequently than the S(6)(a) allele from an Asian cultivated rice strain (O. sativa) through both male and female gametes in heterozygous plants. Here, we report on the effect of a difference in genetic background on S(6) locus-mediated siTRD, based on the analysis using near-isogenic lines and the original wild strain as a parental strain for crossing. We found that the degree of TRD through the male gametes varied depending on the genetic background of the female (pistil) plants. Despite the occurrence of TRD through both male and female gametes, abnormality was detected in ovules, but not in pollen grains, in the heterozygote. These results suggest the involvement of unlinked modifiers and developmentally distinct, sex-specific genetic mechanisms in S(6) locus-mediated siTRD, raising the possibility that siTRD driven by a single locus may be affected by multiple genetic factors harbored in natural populations.


Assuntos
Cruzamentos Genéticos , Oryza/genética , Alelos , Mapeamento Cromossômico , Cromossomos de Plantas , Frequência do Gene , Ordem dos Genes , Loci Gênicos , Genótipo , Meiose , Pólen/genética , Reprodução/genética
7.
Tech Coloproctol ; 16(2): 143-5, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22083443

RESUMO

Stomal prolapse is one of the common complications in transverse colostomy and can be managed conservatively in most cases; however, laparotomy and reconstruction of the stoma may sometimes be required, especially in case of irreducible colostomy prolapse. We have reported a simple local repair with reconstruction of the loop colostomy. We herein report a new more simple technique to avoid laparotomy and allow excision of the irreducible colostomy prolapse and complete closure of the distal limb of loop colostomy when no decompression is required in the distal limb of the stoma. In this procedure, the number of stapler and the time with blood loss for the operation can be saved.


Assuntos
Doenças do Colo/cirurgia , Colostomia/efeitos adversos , Grampeadores Cirúrgicos , Perda Sanguínea Cirúrgica , Humanos , Prolapso , Fatores de Tempo
8.
Nanotechnology ; 22(16): 165704, 2011 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-21393818

RESUMO

Excellent photoconductive properties have been found in Sb(2)O(3) nanobelts synthesized by a surfactant-assisted solvothermal method. Visible-light photodetectors have been designed from Sb(2)O(3) nanobelt networks using micrometer-wide gold wires as masks. Photodetectors show high sensitivity to visible light, high stability, and reproducibility. Fast response and decay times (<0.3 s) are comparable or even better than these parameters in many other metal oxide nanoscale photodetectors. The dominant mechanism of excellent photoconductivity is attributed to the barrier height modulations in the nanobelt-to-nanobelt contact regions. These results demonstrate that Sb(2)O(3) nanobelt networks can indeed serve as high-performance photodetectors in the visible light range.


Assuntos
Nanoestruturas/química , Nanoestruturas/ultraestrutura , Fotometria/instrumentação , Compostos de Estanho/química , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Nanoestruturas/efeitos da radiação , Compostos de Estanho/efeitos da radiação
9.
Int J Cardiovasc Imaging ; 37(7): 2337-2343, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33704588

RESUMO

This study examined whether using an artificial neural network (ANN) helps beginners in diagnostic cardiac imaging to achieve similar results to experts when interpreting stress myocardial perfusion imaging (MPI). One hundred and thirty-eight patients underwent stress MPI with Tc-labeled agents. An expert and a beginner interpreted stress/rest MPI with or without the ANN and the results were compared. The myocardium was divided into 5 regions (the apex; septum; anterior; lateral, and inferior regions), and the defect score of myocardial blood flow was evaluated from 0 to 4, and SSS, SRS, and SDS were calculated. The ANN effect, defined as the difference in each of these scores between with and without the ANN, was calculated to investigate the influence of ANN on the interpreters' performance. We classified 2 groups (insignificant perfusion group and significant perfusion group) and compared them. In the same way, classified 2 groups (insignificant ischemia group and significant ischemia group) and compared them. Besides, we classified 2 groups (normal vessels group and multi-vessels group) and compared them. The ANN effect was smaller for the expert than for the beginner. Besides, the ANN effect for insignificant perfusion group, insignificant ischemia group and multi-vessels group were smaller for the expert than for the beginner. On the other hand, the ANN effect for significant perfusion group, significant ischemia group and normal vessels group were no significant. When interpreting MPI, beginners may achieve similar results to experts by using an ANN. Thus, interpreting MPI with ANN may be useful for beginners. Furthermore, when beginners interpret insignificant perfusion group, insignificant ischemia group and multi-vessel group, beginners may achieve similar results to experts by using an ANN.


Assuntos
Imagem de Perfusão do Miocárdio , Coração , Humanos , Redes Neurais de Computação , Perfusão , Valor Preditivo dos Testes , Tomografia Computadorizada de Emissão de Fóton Único
10.
Phys Rev Lett ; 105(4): 045004, 2010 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-20867854

RESUMO

A complex multistage transition of the edge radial electric field is observed in JT-60U H-mode phase without edge localized mode. An interesting feature is that the poloidal rotation velocity of the carbon impurity ions changes in the later H-phase without a comparable change in the main ion pressure gradient, indicating a change in the parallel momentum (and particle) balance channel.

11.
J Appl Microbiol ; 109(1): 156-65, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20028436

RESUMO

AIMS: Prolyl aminopeptidase (PAP) degrades only amino-terminal proline from peptides. The food-grade fungus Aspergillus oryzae produces this enzyme only in small amounts. In this paper, we present efficient production of recombinant PAP with an overexpression system of A. oryzae and characterization of its biochemical properties. METHODS AND RESULTS: The gene encoding PAP was overexpressed as a His-tag fusion protein under a taka-amylase gene (amyB) promoter with a limited expressing condition in A. oryzae. The PAP activity in the mycelia grown in rich medium containing glucose (repressing condition) was twice that in starch (inducing condition). The enzyme prepared as cell-free extract was partially purified through two-step column chromatography. The PAP was estimated to be a hexameric protein and exhibited salt tolerance against NaCl of up to 4 mol l(-1). CONCLUSIONS: Aspergillus oryzae PAP was produced under the repressing condition of amyB promoter in a PAP-overexpressing strain and purified 1800-folds. Overproduction of PAP under promoter-inducing conditions led to an increase in inactive PAP, possibly because of irregular folding. SIGNIFICANCE AND IMPACT OF THE STUDY: PAP with a high specific activity and salt tolerance may be used effectively in the manufacturing processes of fermented foods.


Assuntos
Aminopeptidases/biossíntese , Aspergillus oryzae/enzimologia , Microbiologia Industrial , Aminopeptidases/genética , Aminopeptidases/metabolismo , Aspergillus oryzae/genética , Meios de Cultura , Regiões Promotoras Genéticas , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
12.
Lett Appl Microbiol ; 50(4): 386-92, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20149082

RESUMO

AIM: To develop a detection assay for staphylococcal mecA and spa by using loop-mediated isothermal amplification (LAMP) method. METHODS AND RESULTS: Staphylococcus aureus and other related species were subjected to the detection of mecA and spa by both PCR and LAMP methods. The LAMP successfully amplified the genes under isothermal conditions at 64 degrees C within 60 min, and demonstrated identical results with the conventional PCR methods. The detection limits of the LAMP for mecA and spa, by gel electrophoresis, were 10(2) and 10 cells per tube, respectively. The naked-eye inspections were possible with 10(3) and 10 cells for detection of mecA and spa, respectively. The LAMP method was then applied to sputum and dental plaque samples. The LAMP and PCR demonstrated identical results for the plaque samples, although frequency in detection of mecA and spa by the LAMP was relatively lower for the sputum samples when compared to the PCR methods. CONCLUSION: Application of the LAMP enabled a rapid detection assay for mecA and spa. The assay may be applicable to clinical plaque samples. SIGNIFICANCE AND IMPACT OF THE STUDY: The LAMP offers an alternative detection assay for mecA and spa with a great advantage of the rapidity.


Assuntos
Proteínas de Bactérias/análise , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Proteína Estafilocócica A/análise , Idoso , Idoso de 80 Anos ou mais , Técnicas Bacteriológicas , DNA Bacteriano/isolamento & purificação , Placa Dentária/microbiologia , Humanos , Limite de Detecção , Staphylococcus aureus Resistente à Meticilina/genética , Pessoa de Meia-Idade , Proteínas de Ligação às Penicilinas , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
14.
J Appl Microbiol ; 105(5): 1711-9, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18828788

RESUMO

AIMS: Aspartyl aminopeptidase (DAP) has a high degree of substrate specificity, degrading only amino-terminal acidic amino acids from peptides. Therefore, attention is focused here on the efficient production of this enzyme by a recombinant Aspergillus oryzae and characterization of its biochemical properties. METHODS AND RESULTS: The gene encoding DAP was overexpressed under a taka-amylase gene promoter, with His-tag linker in A. oryzae, during cultivation in a Co(2+)-containing medium. The enzyme was extracted from the mycelia and purified with immobilized nickel ion absorption chromatography using a buffer containing cobalt ion and imidazole. The active fraction was further purified with gel filtration chromatography. The resultant, electrophoretically pure enzyme displayed a molecular mass of 520 kDa. This enzyme displayed high reactivity towards peptide substrate rather than synthetic substrates. CONCLUSIONS: Recombinant A. oryzae DAP was purified to homogeneity with an increased specific activity, when cultivated in a Co(2+)-rich medium. Moreover, the use of suitable metal ions in microbial cultivation and purification processes may help in increasing the specific activity of other metalloproteases and their functional analysis. SIGNIFICANCE AND IMPACT OF THE STUDY: Recombinant DAP produced using a cobalt ion in culture media of A. oryzae and purification process allow high yield of the enzyme activity.


Assuntos
Aspergillus oryzae/enzimologia , Glutamil Aminopeptidase/isolamento & purificação , Aspergillus oryzae/genética , Cromatografia em Gel , Cromatografia por Troca Iônica , Cobalto/farmacologia , Meios de Cultura/química , Glutamil Aminopeptidase/metabolismo , Peso Molecular , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Especificidade por Substrato
15.
Rev Sci Instrum ; 79(5): 053506, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18513068

RESUMO

A new technique to measure the first and second derivatives of the ion temperature profile has been developed by using a charge exchange spectroscopy system with space modulation optics. The space observed is scanned up to +/-3 cm with a cosine wave modulation frequency up to 30 Hz by shifting the object lens in front of the optical fiber bundle by 0.5 mm with a piezoelement. The first and second derivatives of ion temperature are derived from the modulation component of the ion temperature measured by using Fourier series expansion.

16.
J Clin Invest ; 77(4): 1382-6, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2937806

RESUMO

A new strategy was shown for the manipulation of autoantibody production in humans. Antiidiotypic antibody to human anti-DNA autoantibody was conjugated with neocarzinostatin (NCS), a cytotoxic agent, by using N-succimidyl 3-(2-pyridyldithio) propionate as a coupling agent. Human B cell clones, which produce anti-DNA autoantibodies, were killed by in vitro treatment with antiidiotype (Id)-NCS conjugates, while clones expressing an Id with irrelevant specificity were unaffected. These results indicate that treatment with anti-Id-NCS conjugates can act as a potent and specific means of generating immunosuppression of autoantibody production. This approach will have a significant advantage in aborting clones that are not effectively suppressed for the autoantibodies by anti-Id antibodies alone, and will result in a potential therapeutic treatment for systemic lupus erythematosus.


Assuntos
Antibióticos Antineoplásicos/metabolismo , Anticorpos Anti-Idiotípicos/imunologia , Autoanticorpos/isolamento & purificação , DNA/imunologia , Idiótipos de Imunoglobulinas/imunologia , Zinostatina/metabolismo , Anticorpos Monoclonais , Linfócitos B/metabolismo , Células Cultivadas , Citometria de Fluxo , Fluorescência , Humanos
17.
J Natl Cancer Inst ; 59(4): 1099-105, 1977 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20513

RESUMO

Natural cell-mediated cytotoxicity (NCMC) and antibody-dependent cell-mediated cytotoxicity (ADCC) appeared to involve similar cytotoxic mechanisms; effector N-cells killed target cells with IgG antibodies attached to the Fc receptor determining the specificity of the reaction. In NCMC the wide range of specificities detected by natural antibodies provided an effector system capable of recognizing numerous antigens on cultured target cells. When several target cells were tested concurrently, an apparent nonselective cytotoxicity resulted. The specificity of individual reactions against each of the target cells could be demonstrated by selective inhibition with competitor cells. The inhibition of cytotoxicity by competition and the effect of proteases on the effector cell for NCMC, but not for ADCC, initially suggested an antibody on the surface of the natural cytotoxic effector cell. This suggestion was supported by the loss of activity with treatments that removed immunoglobulins on the effector cell and by the recovery of reactivity with incubation of the cells in normal human serum. Absorption of the reconstituting serum with target cells resulted in loss of activity against that target cell, substantiating the role of natural antibodies.


Assuntos
Anticorpos , Citotoxicidade Imunológica , Imunidade Celular , Imunidade Inata , Linfócitos/imunologia , Especificidade de Anticorpos , Citotoxicidade Imunológica/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Imunidade Celular/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Fragmentos Fc das Imunoglobulinas , Imunoglobulina G , Técnicas In Vitro , Peptídeo Hidrolases/farmacologia
18.
Cancer Res ; 45(3): 1314-9, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2578877

RESUMO

Mouse monoclonal antibodies were produced against MT-2 cell line derived from adult T-cell leukemia or human T-cell leukemia virus-rich fraction therefrom. Two IgG1 antibodies, Ta60a and Ta60b, were found to be reactive not only with cell lines derived from adult T-cell leukemia or cutaneous T-cell lymphomas, but also with activated peripheral blood lymphocytes, suggesting the similarity of Ta60 antigen group to Tac antigen which is present on interleukin 2 receptor. Thus, the relationship among these antigens was studied. Two Ta60 antibodies and Tac antibody immunoprecipitated the molecule with almost identical electrophoretic mobility, approximately a Mr 60,000 antigen from [3H]glucosamine-labeled activated peripheral blood lymphocytes or MT-2, MT-1, or ATN-1 cells from adult T-cell leukemia and a Mr 53,000 antigen from HUT-102 cells derived from cutaneous T-cell lymphomas. Further, Tac antibody was found to immunoprecipitate Ta60b molecule on 125I-labeled MT-2 cells by sequential immunoprecipitation, indicating that these two epitopes are on the same molecule. Antibody binding inhibition assays with either 3H-labeled Ta60a or Ta60b antibody demonstrated that Ta60a and Tac are the same epitope, but different from Ta60b. Thus, at least two epitopes were demonstrated to be present on interleukin 2 receptor molecule. However, Ta60b antibody showed almost no blocking effects on proliferation of an interleukin-2-dependent cell line, whereas Ta60a antibody did. Various hematopoietic tumor cells were typed with these two antibodies, but the results with Ta60b antibody were described, because they showed a similar specificity. Ta60b antibody reacted with all adult T-cell leukemia cases, but did not react with T-cell acute lymphoblastic leukemia, lymphoblastic lymphoma, or mature T-cell lymphoma. Interestingly, 3 of 12 acute myeloblastic leukemia and 2 of 5 chronic myelocytic leukemia in blastic crisis showed positive reactions. One-third of B-cell chronic lymphocytic leukemia and B-cell lymphoma as well as a few B-cell lines were also weakly reactive with this antibody. A part of the results with direct tests was confirmed by the absorption tests. The results obtained demonstrated the presence of Ta60b on a certain fraction of malignant hematopoietic cells of other than T-cell origin.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos de Neoplasias/imunologia , Epitopos/análise , Leucemia/imunologia , Ativação Linfocitária , Linfócitos/imunologia , Linhagem Celular , Sistema Hematopoético/imunologia , Humanos , Receptores Imunológicos/análise , Receptores de Interleucina-2 , Linfócitos T
19.
Biochim Biophys Acta ; 1311(3): 143-9, 1996 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-8664340

RESUMO

A synthetic peptide corresponding to the N-terminal amino acid residues of stanniocalcin (STC1-20) and including a region that is known to be an active site in teleosts was prepared and tested for its effects on the metabolism of mammalian bone in vitro. STC1-20 (10(-10)-10(-12) M) inhibited increases in the number of tartrate-resistant acid phosphatase-positive, multinucleated cells promoted by an N-terminal fragment of human parathyroid hormone (hPTH1-34) in cultures of murine hemopoietic cells. STC1-20 also slightly decreased the rate of loss of radioactivity from calvariae of fetal rats that had been prelabeled with 45Ca, both with and without stimulation by hPTH1-34. The accumulation of cAMP induced by hPTH1-34 in ROS 17/2.8-5 cells was suppressed by STC1-20 (10(-10)-10(-12) M). Treatment with STC1-20 (10(-11)-10(-13) M) caused increases of the rate of incorporation of [3H]proline into the collagenase-digestible protein of calvariae in newborn mice. From these results, it appears that STC1-20 has diverse effects on the metabolism of mammalian bone, causing a biphasic response. Such effects have not been observed with intact stanniocalcin or with materials from the corpuscles of Stannius and they are also different from the effects of hPTH1-34.


Assuntos
Osso e Ossos/metabolismo , Cálcio/metabolismo , Glicoproteínas/farmacologia , Hormônios/farmacologia , Fragmentos de Peptídeos/farmacologia , Fosfatase Ácida/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Osso e Ossos/efeitos dos fármacos , Contagem de Células/efeitos dos fármacos , AMP Cíclico/metabolismo , Feminino , Glicoproteínas/química , Hormônios/química , Humanos , Isoenzimas/metabolismo , Camundongos , Dados de Sequência Molecular , Hormônio Paratireóideo/farmacologia , Fragmentos de Peptídeos/síntese química , Ratos , Ratos Sprague-Dawley , Salmão , Homologia de Sequência de Aminoácidos , Crânio , Fosfatase Ácida Resistente a Tartarato , Teriparatida , Células Tumorais Cultivadas
20.
Exp Hematol ; 17(7): 795-9, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2502422

RESUMO

The effects of recombinant preparations of human interferon-gamma (rIFN-gamma) and tumor necrosis factor (rTNF), alone or in combination, on class I or class II major histocompatibility complex (MHC) antigen induction were studied using K562, a multipotent hematopoietic precursor cell line. Class I antigens were weakly induced by rIFN-gamma; however, rTNF at any concentration examined (1-1000 U/ml) showed no effect on the induction of class I or class II antigens in the cells. rIFN-gamma (600 U/ml) induced approximately 20% of the cells to express class I antigens after 72-h exposure, whereas 81% of the cells demonstrated class I antigens on their cell surfaces when the cells were simultaneously exposed to 600 U/ml of rIFN-gamma and 1000 U/ml of rTNF. The class II MHC antigens were not induced by the treatments with rIFN-gamma or rTNF, alone or in combination. A synergistic increase of mRNA for class I MHC molecules was demonstrated by treatments of the cells with rIFN-gamma and rTNF in combination. rTNF, but not rIFN-gamma, weakly induced granulocyte-monocyte antigens on the cell surface; however, no synergism was observed on the induction of these antigens by the combined treatments with rIFN-gamma and rTNF. These results indicate that class I MHC antigen expression on K562 cells can be induced by IFN-gamma in cooperation with TNF in a manner different from myeloid antigen expression.


Assuntos
Antígenos de Histocompatibilidade Classe I/imunologia , Interferon gama/farmacologia , Leucemia Mieloide/patologia , Fator de Necrose Tumoral alfa/farmacologia , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Regulação da Expressão Gênica/efeitos dos fármacos , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Técnicas In Vitro , RNA Mensageiro/genética , Proteínas Recombinantes , Células Tumorais Cultivadas
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