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1.
Hum Exp Toxicol ; 40(12): 2048-2062, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34053323

RESUMO

PURPOSE: The mechanism of cytotoxicity of silibinin on two human hepatocellular carcinoma (HCC) cell lines, HepG2 (p53 wild-type) and Hep3B cells (p53 null), is examined in relation with the induction of autophagy and phosphorylation of AMP-activated protein kinase (p-AMPK). MATERIALS AND METHODS: Levels of apoptosis in relation to the levels of autophagy and those of glycolysis-related proteins, glucose transporter 1/4 (Glut1/4) and hexokinase-II (HK2), in HepG2 and Hep3B cells were examined. RESULTS: Silibinin-induced apoptosis was incomplete for HCC cell death in that up-regulated autophagy and/or reduced level of glycolysis, which are induced by silibinin treatment, antagonized silibinin-induced apoptosis. Inhibition of autophagy with 3-methyl adenine (3MA) or blocking of AMP-activated protein kinase (AMPK) activation with Compound C (CC) enhanced silibinin-induced apoptosis. The results confirm that AMPK involved in autophagy as well as in glycolysis remaining with silibinin is responsible for attenuation of silibinin-induced apoptosis. Blocking of AMPK or autophagy contributes to the enhancement of silibinin's cytotoxicity to HepG2 and Hep3B cells. CONCLUSION: This study shows that incomplete apoptosis of HCC by silibinin treatment becomes complete by repression of autophagy and/or glycolysis.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Silimarina/farmacologia , Proteínas Quinases Ativadas por AMP/metabolismo , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/metabolismo , Fosforilação/efeitos dos fármacos , Poli(ADP-Ribose) Polimerases/metabolismo
2.
Cancer Gene Ther ; 17(3): 147-54, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19745843

RESUMO

Natural killer (NK) cells hold promise for cancer therapy. NK cytotoxicity can be enhanced by expression of chimeric antigen receptors that re-direct specificity toward target cells by engaging cell surface molecules expressed on target cells. We developed a regulatory-compliant, scalable non-viral approach to engineer NK cells to be target-specific based on transfection of mRNA encoding chimeric receptors. Transfection of eGFP mRNA into ex vivo expanded NK cells (N=5) or purified unstimulated NK cells from peripheral blood (N=4) resulted in good cell viability with eGFP expression in 85+/-6% and 86+/-4%, 24 h after transfection, respectively. An mRNA encoding a receptor directed against CD19 (anti-CD19-BB-z) was also transfected into NK cells efficiently. Ex vivo expanded and purified unstimulated NK cells expressing anti-CD19-BB-z exhibited enhanced cytotoxicity against CD19(+) target cells resulting in > or =80% lysis of acute lymphoblastic leukemia and B-lineage chronic lymphocytic leukemia cells at effector target ratios lower than 10:1. The target-specific cytotoxicity for anti-CD19-BB-z mRNA-transfected NK cells was observed as early as 3 h after transfection and persisted for up to 3 days. The method described here should facilitate the clinical development of NK-based antigen-targeted immunotherapy for cancer.


Assuntos
Antígenos CD19/metabolismo , Células Matadoras Naturais/metabolismo , Receptores de Antígenos/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Sobrevivência Celular/fisiologia , Células Cultivadas , Eletroporação , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Imunofenotipagem , Células Matadoras Naturais/citologia , Receptores de Antígenos/genética , Transfecção
3.
J Appl Microbiol ; 102(4): 1159-66, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17381760

RESUMO

AIMS: To investigate the influence of avilamycin (AVM) administration and its subsequent withdrawal on the emergence and disappearance of AVM-resistant enterococci in the intestine of broiler chickens. METHODS AND RESULTS: Five chicks each of C, L and H groups were given the basal diet, the basal diet supplemented with 5 g AVM/ton and the basal diet supplemented with 50 g AVM/ton, respectively. The AVM-resistant Enterococcus faecalis population did not emerge during 30 days of the AVM administration period, whereas the AVM-resistant Enterococcus faecium with a minimum inhibitory concentration of >512 microg ml(-1) in the faeces of chicks of the L and H groups emerged on 3 and 1 days after the AVM administration, respectively. Thereafter, the AVM-resistant Ent. faecium population density in both L and H groups maintained high levels during the AVM administration period. Twenty days after the AVM withdrawal, the AVM-resistant Ent. faecium population disappeared from the intestines of both four of five chicks of L group and three of five chicks of H group. The AVM-resistant Ent. faecium population density in one chick from each of the groups, L and H, did not change before and after the AVM removal. CONCLUSIONS: The AVM-resistant Ent. faecium emerged during the AVM administration, and disappeared from the intestine of most chicks after the AVM withdrawal. However, the AVM-resistant Ent. faecium persisted in some chicks 20 days after AVM withdrawal. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results suggest that introducing an AVM withdrawal period could minimize the risk of AVM-resistant Ent. faecium becoming carcass contaminants, and that prudent antibiotic use alone is not sufficient to stem emergence of the AVM-resistant Ent. faecium.


Assuntos
Ração Animal/microbiologia , Antibacterianos/farmacologia , Galinhas/microbiologia , Enterococcus faecium/efeitos dos fármacos , Microbiologia de Alimentos , Oligossacarídeos/farmacologia , Animais , Contagem de Colônia Microbiana , Farmacorresistência Bacteriana , Enterococcus faecium/crescimento & desenvolvimento , Enterococcus faecium/isolamento & purificação
4.
Kyobu Geka ; 56(8 Suppl): 712-7, 2003 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-12910957

RESUMO

We performed off-pump coronary artery bypass grafting (CABG) in all cases without reoperation case from July, 2002. Advantage of off-pump CABG versus on-pump CABG which is reduced a number of perioperative complication and early patients recovery was previously demonstrated. In our institute, the mean number of grafts per patients was 4.7 +/- 1.3, and the rate of using arterial grafts was 99.5% in all cases without minimally invasive direct coronary artery bypass (MIDCAB). The mean hospital stay after operation was 10.8 +/- 2.8. It was shorted remarkably in comparison with on-pump CABG; 19.4 +/- 6. Furthermore, sever complication was not occurred in any cases after operation though high risk cases were increased. In the early cases, atrial fibrillation complicated frequently (32%), but using after magnesium sulfate it was remarkably decreased (8.4%). On the other-hand, attention is necessary for the infection caused by the increase of high risk patients. Therefore, we used vancomycin (VCM) at these cases from the viewpoint of prevention. Recently, we performed remnant omental transfer for the sever diabetes mellitus case which was used bilateral internal thoracic artery on CABG. It learned to get the early recovery which was necessary for the off-pump CABG by the above additional treatment.


Assuntos
Ponte de Artéria Coronária/métodos , Doença das Coronárias/cirurgia , Tempo de Internação , Assistência Perioperatória , Antibioticoprofilaxia , Fibrilação Atrial/tratamento farmacológico , Ponte Cardiopulmonar/estatística & dados numéricos , Ponte de Artéria Coronária/estatística & dados numéricos , Humanos , Sulfato de Magnésio/uso terapêutico , Artéria Torácica Interna/transplante , Omento/transplante , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/terapia , Estudos Retrospectivos , Risco , Infecções Estafilocócicas/prevenção & controle , Resultado do Tratamento , Vancomicina/uso terapêutico
5.
Bone Marrow Transplant ; 29(7): 595-8, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11979309

RESUMO

Human herpesvirus 6 (HHV-6) infection and disease are serious complications of allogeneic hematopoietic stem cell transplantation (allo-SCT). Ganciclovir (GCV) is effective against HHV-6 in vitro but the antiviral susceptibility of HHV-6 has not been well characterized in vivo. We retrospectively compared the HHV-6 reactivation rate in pediatric allo-SCT recipients with and without GCV prophylaxis. The HHV-6 reactivation rate at 3 weeks after allo-SCT in patients without prophylactic GCV administration was significantly higher than that in those receiving prophylactic GCV (11/28 vs 0/13, P < 0.01). Five of 36 patients without prophylactic GCV showed clinical manifestations including skin rash, interstitial pneumonitis, persistent thrombocytopenia, enterocolitis and thrombotic microangiopathy, respectively. HHV-6-associated symptoms were observed in one of the 13 patients receiving prophylactic GCV. This patient showed fever, diarrhea and graft rejection concomitantly with a sudden increase of HHV-6 DNA copy number. Patients who received GCV for treatment of HHV-6 infection showed an improvement in symptoms and/or decrease of HHV-6 copy number. Thus, GCV is effective for treating HHV-6 disease after allo-SCT in vivo.


Assuntos
Antivirais/uso terapêutico , Ganciclovir/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Herpesvirus Humano 6/efeitos dos fármacos , Infecções por Roseolovirus/prevenção & controle , Criança , DNA Viral/sangue , Avaliação de Medicamentos , Feminino , Herpes Zoster/prevenção & controle , Herpesvirus Humano 6/crescimento & desenvolvimento , Herpesvirus Humano 6/isolamento & purificação , Humanos , Masculino , Reação em Cadeia da Polimerase , Estudos Retrospectivos , Infecções por Roseolovirus/tratamento farmacológico , Infecções por Roseolovirus/epidemiologia , Infecções por Roseolovirus/mortalidade , Transplante Homólogo , Viremia/tratamento farmacológico , Ativação Viral/efeitos dos fármacos
6.
Int J Hematol ; 74(3): 338-41, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11721973

RESUMO

Unrelated cord blood transplantation (CBT) has been worldwide for bone marrow reconstitution. CBT is associated with a high frequency of engraftment failure and rejection due to a small dose of graft cells. In cases of engraftment failure or rejection following unrelated CBT, retransplantation from the original donors is impossible. We report a successful transplantation with CD34+ blood cells selected from a 2-loci HLA-mismatched mother to a child with acute monocytic leukemia after engraftment failure of the primary CBT. Selected CD34+ blood cell transplantation is a useful approach for retransplantation in the setting of engraftment failure.


Assuntos
Antígenos CD34 , Células Sanguíneas/transplante , Transplante de Células-Tronco Hematopoéticas , Adulto , Antígenos CD34/análise , Células Sanguíneas/citologia , Células Sanguíneas/imunologia , Intervalo Livre de Doença , Feminino , Sangue Fetal/citologia , Sobrevivência de Enxerto , Histocompatibilidade , Teste de Histocompatibilidade , Humanos , Recém-Nascido , Leucemia Monocítica Aguda/terapia , Masculino
7.
Bone Marrow Transplant ; 27(9): 977-82, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11436109

RESUMO

To assess the involvement of vascular endothelial cell activation and damage in stem cell transplantation (SCT)-related complications, such as acute and chronic GVHD and thrombotic microangiopathy (TMA), we investigated the changes in serum levels of soluble forms of vascular cell adhesion molecule-1 (sVCAM-1) and E-selectin (sE-selectin) in SCT. The soluble form of intercellular adhesion molecule-1 (sICAM-1) was also analyzed. In patients with acute GVHD (grades II-IV), serum levels of sE-selectin and sICAM-1 increased around onset of GVHD (day 30). While the increase of sE-selectin levels was transient, sICAM-1 levels remained high until day 60. In patients with extensive chronic GVHD, sVCAM-1 as well as sE-selectin levels significantly increased. The appearance of clinical symptoms was preceded by elevations of sVCAM-1 and sE-selectin levels on day 60, and sICAM-1 levels on days 30 and 60. For the analysis of TMA, to exclude the influence of GVHD, serum levels were measured in auto-SCT patients. Around the onset of TMA, sVCAM-1 and sE-selectin levels significantly increased in patients with TMA without an increase of sICAM-1 levels. These findings support the notion that activation and injury of endothelium are commonly involved in the pathogenesis of acute and chronic GVHD and TMA.


Assuntos
Moléculas de Adesão Celular/sangue , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Adolescente , Biomarcadores/sangue , Criança , Pré-Escolar , Selectina E/sangue , Endotélio Vascular/lesões , Endotélio Vascular/metabolismo , Doença Enxerto-Hospedeiro/sangue , Doença Enxerto-Hospedeiro/etiologia , Humanos , Lactente , Molécula 1 de Adesão Intercelular/sangue , Leucemia/complicações , Leucemia/terapia , Solubilidade , Trombose/sangue , Trombose/etiologia , Fatores de Tempo , Transplante Autólogo/efeitos adversos , Transplante Homólogo/efeitos adversos , Molécula 1 de Adesão de Célula Vascular/sangue
8.
Bone Marrow Transplant ; 27(10): 1065-70, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11438822

RESUMO

Human herpesvirus-6 (HHV-6) and -7 were analyzed in 25 and 18 patients with allogeneic (allo) and autologous (auto) stem cell transplantation (SCT), respectively, by weekly examination of viral DNA in peripheral mononuclear cells using semiquantitative PCR and serologic tests up to 12 weeks after SCT. HHV-6 DNA was detected in 29.6% and 27.9% of samples after allo- and auto-SCT, respectively. The proportions of HHV-6-DNA-positive samples increased in week 3 and 4 after allo-SCT, and in week 1 to 3 after auto-SCT. The frequency of HHV-7 DNA detection, however, was higher after auto-SCT (24.7%) than allo-SCT (12.8%) (P 10(2) copies of HHV-6 DNA (/10(5) cells) on two consecutive occasions were allo-SCT recipients and three showed clinical episodes. Conversely, three of five patients with continuous reactivation of HHV-7 were auto-SCT recipients. Thus, the frequencies of HHV-6 and -7 DNA detection showed an inverse relationship comparing allo- and auto-SCT, suggesting a different mechanism may regulate HHV-6 and -7 reactivation.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Herpesvirus Humano 6/crescimento & desenvolvimento , Herpesvirus Humano 7/crescimento & desenvolvimento , Transplante Autólogo/efeitos adversos , Transplante Homólogo/efeitos adversos , Adolescente , Adulto , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , DNA Viral/sangue , DNA Viral/classificação , Feminino , Herpesvirus Humano 6/genética , Herpesvirus Humano 7/genética , Humanos , Lactente , Masculino , Reação em Cadeia da Polimerase , Ativação Viral
9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 63(6 Pt 2): 066221, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11415220

RESUMO

Chaos in the multimode nonadiabatic system constructed by Heller [J. Chem. Phys. 92, 1718 (1990)], which consists of two diabatic two-dimensional harmonic potentials with the Condon coupling, is studied. A thorough investigation is carried out by scanning the magnitudes of the Condon coupling and the Duschinsky angle. To elucidate mechanisms that can cause chaos in this quantum system, the statistical properties of the energy levels and eigenfunctions of the system are investigated. We find an evidence in terms of the nearest-neighbor spacing distribution of energy levels and other measures that a certain class of chaos is purely induced by the nonadiabatic interaction due to breakdown of the Born-Oppenheimer approximation. Since the nonadiabatic transition can induce repeated bifurcation and merging of a wave packet around the region of quasicrossing between two potential surfaces, and since this interaction does not have a counterpart in the lower adiabatic system, the present chaos deserves being called "nonadiabatic chaos." Another type of chaos in a nonadiabatic system was previously identified [D. M. Leitner et al., J. Chem. Phys. 104, 434 (1996)] that reflects the inherent chaos of a corresponding adiabatic potential. We present a comparative study to establish the similarity and difference between these kinds of chaos.

10.
Bone Marrow Transplant ; 26(6): 681-3, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11041570

RESUMO

We report a 5-year-old boy with juvenile myelomonocytic leukemia (JMML) which relapsed after an allogeneic bone marrow transplant who was successfully treated with interferon-alpha (IFN-alpha). One year after starting the therapy, he remains clinically well and in complete remission while continuing treatment with IFN-alpha and bestatin. Although the precise mechanism by which remission was induced is uncertain, a GVL effect combined with a direct antileukemia effect of IFN-alpha may be responsible. Further assessment of the role of IFN-alpha in relapsed JMLL patients is warranted.


Assuntos
Antineoplásicos/uso terapêutico , Transplante de Medula Óssea , Interferon-alfa/uso terapêutico , Leucemia Mielomonocítica Crônica/terapia , Pré-Escolar , Terapia Combinada , Efeito Enxerto vs Leucemia , Humanos , Leucemia Mielomonocítica Crônica/tratamento farmacológico , Masculino
11.
Int J Hematol ; 72(1): 69-73, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10979212

RESUMO

We analyzed the expression pattern of adhesion molecules including beta 1-integrins (CD49c, CD49d, CD49e, CD49f), beta 2-integrins (CD11a, CD11b, CD11c), CD44, and CD54 in 141 children with B-cell precursor acute lymphoblastic leukemia (pre-B ALL) and in 21 children with B-cell ALL/non-Hodgkin's lymphoma (B-ALL/NHL). The frequencies of CD11a, CD49f, and CD44 expression were significantly higher in CD34+ pre-B ALL than in CD34- pre-B ALL. Although CD49d, CD49e, and CD44 were less frequently expressed in B-ALL/NHL than in pre-B ALL, the expression of CD11a and CD54 were more frequent in B-ALL/NHL. In pre-B ALL, expression of CD11a positively correlated with that of CD11b (P < .05) and CD54 (P < .01), and CD49c positively correlated with CD49f (P < .01). Of the clinical parameters of patients with pre-B ALL, expression of CD11a was associated with a low leukocyte count (P < .05). The presence of CD54 on the cell surface was an independent factor indicating a poor prognosis. The estimated 5-year event-free survival was 42.3% for CD54+ (n = 31) compared with 70.3% for CD54- patients (n = 38) (P < .05). These findings demonstrated that expression of adhesion molecules is dependent on the phenotype of B-lineage cells and that the expression of some of these molecules has clinical significance.


Assuntos
Linfoma de Burkitt/metabolismo , Moléculas de Adesão Celular/metabolismo , Linfoma de Células B/metabolismo , Antígenos CD/metabolismo , Células da Medula Óssea/imunologia , Células da Medula Óssea/patologia , Linfoma de Burkitt/diagnóstico , Linfoma de Burkitt/patologia , Imunofenotipagem , Integrinas/metabolismo , Linfoma de Células B/diagnóstico , Linfoma de Células B/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Prognóstico
12.
Arch Histol Cytol ; 63(1): 71-9, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10770590

RESUMO

Macrophages adhere to a variety of substrata including plastic, glass or an extracellular matrix either in a highly specific manner or through less specific mechanisms. We investigated the effect of type I collagen, the most abundant protein in animal tissues, on the adhesion of macrophages derived from a human monoblastic cell line U937. Macrophages were observed to adhere very weakly to type I collagen and aggregate, whereas they adhered firmly and spread on plastic, bovine serum albumin or fibronectin. On the adhesive substratum, the lower surface of the macrophages was flat and closely apposed to the substratum. In contrast, macrophages adhered on type I collagen at the tip of cell processes. The adhesion of macrophages to plastic, bovine serum albumin or fibronectin was associated with the induction of tyrosine phosphorylation of a variety of proteins including a major protein band at 66 kDa. In contrast, the induction of tyrosine phosphorylation was markedly reduced when the macrophages were cultured on type I collagen. Two members of the src family, Lyn and Hck, were tyrosine phosphorylated in firmly adhered macrophages but not in macrophages cultured on type I collagen. These results suggest that the adhesion of macrophages is associated with the tyrosine phosphorylation of a variety of proteins including Lyn and Hck, and that type I collagen serves as a non-adhesive substratum for macrophages, resulting in an altered signal transduction.


Assuntos
Colágeno/fisiologia , Matriz Extracelular/fisiologia , Macrófagos/metabolismo , Anticorpos Monoclonais/metabolismo , Adesão Celular , Linhagem Celular , Ácido Edético/metabolismo , Matriz Extracelular/ultraestrutura , Fibronectinas/metabolismo , Humanos , Integrinas/metabolismo , Macrófagos/fisiologia , Macrófagos/ultraestrutura , Microscopia Eletrônica , Fagocitose , Fosforilação , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-hck , Albumina Sérica/metabolismo , Fatores de Tempo , Tirosina , Quinases da Família src/metabolismo
13.
Kyobu Geka ; 53(3): 251-3, 2000 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-10714119

RESUMO

A 60-year-old female presented in end-stage renal failure. She was introduced continuous ambulatory peritoneal dialysis in August 1997. After about six months, acute hydrothorax developed in her right side of the pleural cavity. Then she was obligated to give up CAPD because of repeated recurrence of hydrothorax. She wanted to return to CAPD for her life style. In November 1998, she came to our hospital to have a surgical treatment for her pleuroperitoneal communication. We performed video assisted thoracoscopic surgery. Using methylene blue containing dialysis solution through CAPD catheter, we found a bleb on the diaphragm that expanded gradually. We diagnosed that potion was pleuroperitoneal communication. The defect of diaphragm was directly closed with surgical stapler. Post-operative course was very favorable. She could restarted CAPD at 3 postoperative day, and discharged from our hospital after 5 days of operation. No recurrence of hydrothorax has been detected for a years after the surgical treatment.


Assuntos
Fístula/cirurgia , Diálise Peritoneal Ambulatorial Contínua/efeitos adversos , Doenças Peritoneais/cirurgia , Doenças Pleurais/cirurgia , Cirurgia Torácica Vídeoassistida , Feminino , Fístula/etiologia , Humanos , Hidrotórax/etiologia , Pessoa de Meia-Idade , Doenças Peritoneais/etiologia , Doenças Pleurais/etiologia , Resultado do Tratamento
14.
Bone Marrow Transplant ; 24(8): 919-23, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10516706

RESUMO

Thrombotic microangiopathy (TMA) is a serious complication of BMT. Several factors are important in the etiology of TMA, such as cyclosporin A, GVHD, irradiation, intensive conditioning chemotherapy and infection, which cause damage to vascular endothelial cells leading to activation of these cells. We describe two young children with TMA following high-dose chemotherapy with autologous BMT. Development of TMA was accompanied by reactivation of HHV-6, which was identified by both an increase in the copy number of HHV-6 DNA in the peripheral blood and a significant increase in antibody titers to HHV-6. Thus, it was suggested that reactivation of HHV-6 together with high-dose chemotherapy played an important role in the pathogenesis of TMA in these patients. Since HHV-6 is known to infect vascular endothelial cells, and CMV which is virologically closely related to HHV-6, has been reported to be a pathogen that causes TMA, infection with HHV-6 of vascular endothelial cells may induce TMA via damage and activation of these cells.


Assuntos
Transplante de Medula Óssea/efeitos adversos , Síndrome Hemolítico-Urêmica/virologia , Hepatoblastoma/terapia , Infecções por Herpesviridae/etiologia , Herpesvirus Humano 6/isolamento & purificação , Leucemia Megacarioblástica Aguda/terapia , Neoplasias Hepáticas/terapia , Trombose/virologia , Terapia Combinada/efeitos adversos , Feminino , Síndrome Hemolítico-Urêmica/etiologia , Hepatoblastoma/patologia , Humanos , Lactente , Leucemia Megacarioblástica Aguda/patologia , Neoplasias Hepáticas/patologia , Masculino , Trombose/etiologia , Transplante Autólogo
15.
J Pharm Pharmacol ; 51(3): 279-84, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10344628

RESUMO

This study was aimed at determining the driving force for spermine transport in rat renal proximal tubular brush-border membrane. The uptake of spermine and trientine, a spermine-like drug used for treating Wilson's disease, into rat renal brush-border membrane vesicles was significantly stimulated by an outwardly directed Na+ gradient. The Na+-dependent uptake was temperature dependent and saturable. A kinetic analysis of the initial uptake of spermine with an Na+ gradient gave a Km value of 1.44 microM and a Vmax value of 6.31 pmol (mg protein)(-1)/30s. The Na+ dependent uptake of [3H]spermine was inhibited by spermine, trientine and tetraethylene-pentamine. Substrates of the H+/organic cation transporter (cimetidine and tetraethyl-ammonium), physiological polyamines (putrescine and spermidine) with 2 or 3 amino groups and aminoglycosides (amikacin and tobramicin) with 4 or 5 cationic amines did not affect the uptake of spermine in the presence of an outwardly directed Na+ gradient. These results suggest that the renal tubular secretion of spermine is mediated by an Na+/spermine antiport system which is specific for a straight-chain polyamine compound with more than 4 amino groups.


Assuntos
Antiporters/fisiologia , Túbulos Renais/fisiologia , Microvilosidades/química , Poliaminas/farmacocinética , Sódio/química , Espermina/farmacocinética , Animais , Interações Medicamentosas , Técnicas In Vitro , Microvilosidades/metabolismo , Ratos , Ratos Wistar , Temperatura , Trientina/farmacocinética
16.
Biophys J ; 76(5): 2412-20, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10233058

RESUMO

A video-rate (30 frames/s) scanning two-photon excitation microscope has been successfully tested. The microscope, based on a Nikon RCM 8000, incorporates a femtosecond pulsed laser with wavelength tunable from 690 to 1050 nm, prechirper optics for laser pulse-width compression, resonant galvanometer for video-rate point scanning, and a pair of nonconfocal detectors for fast emission ratioing. An increase in fluorescent emission of 1.75-fold is consistently obtained with the use of the prechirper optics. The nonconfocal detectors provide another 2.25-fold increase in detection efficiency. Ratio imaging and optical sectioning can therefore be performed more efficiently without confocal optics. Faster frame rates, at 60, 120, and 240 frames/s, can be achieved with proportionally reduced scan lines per frame. Useful two-photon images can be acquired at video rate with a laser power as low as 2.7 mW at specimen with the genetically modified green fluorescent proteins. Preliminary results obtained using this system confirm that the yellow "cameleons" exhibit similar optical properties as under one-photon excitation conditions. Dynamic two-photon images of cardiac myocytes and ratio images of yellow cameleon-2.1, -3.1, and -3.1nu are also presented.


Assuntos
Microscopia de Fluorescência/instrumentação , Microscopia de Vídeo/instrumentação , Fenômenos Biofísicos , Biofísica , Cálcio/metabolismo , Células Cultivadas , Escherichia coli/citologia , Escherichia coli/metabolismo , Estudos de Avaliação como Assunto , Corantes Fluorescentes , Células HeLa , Humanos , Técnicas In Vitro , Lasers , Miocárdio/citologia , Miocárdio/metabolismo , Óptica e Fotônica/instrumentação , Fótons , Células de Purkinje/citologia , Células de Purkinje/metabolismo , Proteínas Recombinantes/metabolismo
17.
Exp Hematol ; 27(5): 826-33, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10340398

RESUMO

Morphophenotypic lineage switches occur in a small percentage of those with acute leukemia, and the underlying mechanisms are not clear. In this study, we attempted to induce a lineage switch in acute myelocytic leukemia (AML) with monosomy 7, whose lineage had switched from acute T-lymphocytic leukemia (T-ALL) during chemotherapy, in severe combined immunodeficient (SCID) mice. Although the transplanted myeloid cells were engrafted in SCID mice without cytokine administration, T-ALL developed in SCID mice treated with recombinant human granulocyte-macrophage colony-stimulating factor or recombinant human interleukin 3. Analysis of the nucleotide sequences of the rearranged T-cell receptor gamma-chain (TCR-gamma) gene revealed that this lineage switch resulted from the selection of the T-lineage subclone in SCID mice, which had expanded at onset. In addition, we found that the T-lineage and myeloid cells belonged to the distinct subclones, which were different in TCR-gamma gene rearrangements, but were derived from a common clone with an identical N-ras gene mutation for both subclones. In in vitro cultures, only the myeloid subclone grew; the T-lineage subclone failed to grow even in the presence of recombinant human granulocyte-macrophage colony-stimulating factor or recombinant human interleukin 3. These results suggested that the initial diagnostic T-lymphoid subclone, whose growth was dependent on these cytokines and the hematopoietic microenvironment, emerged from a bipotential T-lymphoid/myeloid leukemic stem cell, and further genetic event(s) induced the myeloid subclone, which grew independently of these cytokines and the microenvironment.


Assuntos
Linhagem da Célula , Cromossomos Humanos Par 7 , Leucemia Mieloide/patologia , Leucemia-Linfoma de Células T do Adulto/patologia , Monossomia , Doença Aguda , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Sequência de Bases , Pré-Escolar , DNA de Neoplasias , Rearranjo Gênico da Cadeia gama dos Receptores de Antígenos dos Linfócitos T , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Interleucina-3/farmacologia , Cariotipagem , Leucemia Mieloide/genética , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Leucemia-Linfoma de Células T do Adulto/genética , Masculino , Camundongos , Camundongos SCID , Dados de Sequência Molecular , Transplante de Neoplasias , Proteínas Recombinantes/farmacologia , Células Tumorais Cultivadas
18.
Life Sci ; 64(9): 755-61, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10075108

RESUMO

Doxorubicin (DOX=adriamycine), an effective chemotherapeutic agents for cancers, has severe cardiotoxicity. In the paresent study, we examined the protective effect of thermal preconditioning (TP) against apoptosis of rat cardiac muscle cells induced by DOX. Treatment with DOX (10 microM) for 24 hrs resulted in apoptosis of cardiac muscle cells, which was evaluated by examining "DNA ladder" formation and TUNEL staining. The number of TUNEL-positive cells was significantly decreased in cells subjected to TP by incubation at 42 degrees C for 30 min, 24 hrs prior to DOX-treatment. Antisense oligonucleotides of the heat shock protein (HSP) 70 blunted this effect. These results indicate that DOX-induced apoptosis in cardiac muscle cells is prevented by TP, at least in part, via a HSP70-mediated mechanism.


Assuntos
Antineoplásicos/toxicidade , Apoptose , Doxorrubicina/toxicidade , Proteínas de Choque Térmico HSP70/metabolismo , Coração/efeitos dos fármacos , Hipertermia Induzida , Miocárdio/metabolismo , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Células Cultivadas , DNA/análise , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/genética , DNA Complementar/análise , Eletroforese em Gel de Ágar , Proteínas de Choque Térmico HSP70/genética , Temperatura Alta , Marcação In Situ das Extremidades Cortadas , Precondicionamento Isquêmico Miocárdico , Miocárdio/citologia , Oligonucleotídeos Antissenso/farmacologia , Ratos
19.
Pharm Res ; 16(12): 1888-92, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10644079

RESUMO

PURPOSE: To elucidate the effects of drug interactions on the urinary excretion of trientine in rats. METHOD: Trientine and various other drugs were intravenously administered to rats and the urinary excretion of trientine was investigated. To clarify the mechanisms of drug-drug interactions, we also investigated the effects of various drugs on spermine uptake by rat renal brushborder membrane vesicles. RESULTS: Cimetidine, a substrate of the H+/organic cation antiporter, and aminoglycoside antibiotics did not affect trientine excretion, while acetazolamide and furosemide, which increase the concentration of sodium ions in renal proximal tubules, increased the excretion of trientine. However, trichlormethiazide, which acts in renal distal tubules, did not affect trientine excretion. Acetazolamide and furosemide did not directly affect the Na+/spermine transporter because these diuretics had no effect on the uptake of spermine into the rat renal brush-border membrane vesicles. CONCLUSIONS: There is no interaction between trientine and the substrate of the H+/organic cation antiporter or aminoglycoside antibiotics. However, drugs that change the concentration of sodium ions in renal proximal tubules, such as diuretics, can increase the trientine excretion since the increase in the luminal concentration of sodium ion accelerates the Na+/spermine antiporter.


Assuntos
Acetazolamida/farmacologia , Diuréticos/farmacologia , Furosemida/farmacologia , Rim/metabolismo , Trientina/urina , Animais , Cromatografia Líquida de Alta Pressão , Interações Medicamentosas , Injeções Intravenosas , Rim/efeitos dos fármacos , Córtex Renal/efeitos dos fármacos , Córtex Renal/metabolismo , Masculino , Microvilosidades/metabolismo , Ratos , Ratos Wistar , Estimulação Química , Trientina/administração & dosagem
20.
J Immunol ; 161(9): 4695-701, 1998 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-9794399

RESUMO

The mechanisms responsible for myocardial injury and cell death in myocarditis are still unclear. We examined whether myocardial cell death occurs via apoptosis in myosin-induced autoimmune myocarditis in rats and whether the Fas/Fas ligand (FasL) system plays a role in this apoptosis. On days 14, 17, 21, and 35 after immunization with porcine heart myosin, some cardiomyocytes and infiltrating lymphocytes were found to be apoptotic on in situ terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end-labeling (TUNEL) assay, but none was on day 60 and in control rats. Apoptotic indices peaked at day 17, and laddering of genomic DNA from the affected myocardium was observed on days 17 and 21 on agarose gel electrophoresis. The expression of Fas mRNA and protein was detected on days 17 and 21 in some cardiomyocytes and infiltrating lymphocytes by Northern blot analysis and immunohistochemistry, respectively. In addition, FasL was detected in some infiltrating lymphocytes on days 14, 17, and 21 by both in situ hybridization and immunostaining, and FasL-positive lymphocytes were mainly CD4+ cells. Some rats were injected with anti-Fas Ab (0.1 mg/kg) or anti-FasL Ab (0.1 mg/kg), and subsequently, inflammatory lesions exhibited less severe than did untreated rats with myocarditis. These findings suggest that cell death via apoptosis of cardiomyocytes and lymphocytes is one of the mechanisms of myocardial injury in autoimmune myocarditis, and that the Fas/FasL system might play a role in the induction of this apoptosis.


Assuntos
Doenças Autoimunes/imunologia , Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Glicoproteínas de Membrana/imunologia , Miocardite/imunologia , Receptor fas/imunologia , Doença Aguda , Animais , Apoptose , Doenças Autoimunes/patologia , Convalescença , Proteína Ligante Fas , Imunização , Marcação In Situ das Extremidades Cortadas , Masculino , Miocardite/patologia , Miocárdio/imunologia , Miocárdio/patologia , Miosinas/imunologia , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos Lew , Suínos , Receptor fas/genética
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