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1.
RSC Adv ; 12(39): 25669-25674, 2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36199299

RESUMO

Monoalkyl oxalates are among the most important building blocks being applied to the synthesis of a variety of significant classes of compounds or applied to various cutting-edge reactions. However, their commercial availability is limited. Their synthetic methods are also limited because of the difficulty to synthesize them, and those hitherto reported are carried out in organic solvents often with the use of toxic reagents with mostly low to modest yields. Here we have developed practical synthesis of monoalkyl oxalates in aqueous media by applying the highly efficient selective monohydrolysis reactions of symmetric diesters which we reported previously. The best conditions apply an aqueous NaOH solution with relatively nontoxic THF or acetonitrile as a co-solvent at around 0-5 °C. The procedures are simple and environmentally friendly without requiring toxic or expensive reagents, yet yielding the corresponding half-esters in high yields with high purities. All the half-esters prepared here are stable over a long period of time. Therefore, our studies are expected to offer practical green methods for the synthesis of monoalkyl oxalates.

2.
Hepatol Int ; 8(2): 233-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26202504

RESUMO

BACKGROUND: Treatment with systemic corticosteroids is often used for acute liver failure (ALF), but this has increased the number of profoundly immunocompromised patients and cases of opportunistic infection. METHODS: Between January 2007 and December 2012, all patients (n = 51) referred to the Chiba University Hospital for treatment of ALF were studied. Patients with prothrombin activity of 40 % or less of the standardized values were defined as having ALF. Patient age, sex, cause of ALF, alanine aminotransferase and total bilirubin levels, prothrombin activity and total amount of corticosteroid were analyzed to determine the factors associated with the occurrence of opportunistic infection. RESULTS: Opportunistic infections occurred in 21.6 % (n = 11) of ALF patients. Thirty-five patients underwent systemic corticosteroid therapy, and 31.4 % of those patients showed opportunistic infections. Cytomegalovirus (n = 9, 81.8 %) and Pneumocystis jiroveci (n = 6, 54.5 %) were the microorganisms frequently suspected as the causes of opportunistic infection. In 7 (63.6 %) of the 11 cases of opportunistic infection, 2 or more species of microorganism were detected. Seven patients (63.6 %) with opportunistic infection were cured by treatment. Cox regression analysis for the patients who underwent systemic corticosteroid therapy steroid treatment revealed that age over 52 years (compared to younger patients: odds ratio = 9.62, 95 % confidence interval = 1.22-76.9) was only the predictive factor for the occurrence of opportunistic infection. CONCLUSION: Opportunistic infections are not rare in ALF patients, and the appropriate diagnosis and treatment of these infections are critical during ALF treatment.

3.
Clin Vaccine Immunol ; 19(10): 1690-2, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22855394

RESUMO

The immunogenicity of pandemic influenza A H1N1 virus (A/H1pdm) vaccine might be modified by prior seasonal trivalent influenza vaccine (sTIV) administration. We conducted a retrospective analysis of immunogenicity of 243 health care workers (number of sTIV-positive [sTIV(+)] subjects, 216; number of sTIV(-) subjects, 27) by hemagglutination inhibition. There was no significant difference in the ratios of antibody titers of ≥40 (41.2% versus 48.1%; P = 0.49) and fold increases in geometric mean titer (3.8 versus 4.5; P = 0.37). sTIV injected 7 to 10 days prior to A/H1pdm vaccine administration did not interfere with the immunogenicity of the latter.


Assuntos
Anticorpos Antivirais/sangue , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Pessoal de Saúde , Testes de Inibição da Hemaglutinação , Humanos , Vacinas contra Influenza/administração & dosagem , Influenza Humana/imunologia , Pandemias/prevenção & controle , Estudos Retrospectivos , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/imunologia
4.
Rinsho Ketsueki ; 52(11): 1759-64, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22185798

RESUMO

In Japan, we encountered a pandemic expansion of novel influenza A(H1N1) in September 2009, but the impact on patients with underlying disease remained unclear. The Tokyo Children Cancer Study Group (TCCSG) established a "novel influenza information-sharing system" to share real time information on how the novel influenza affects pediatric patients with cancer or other hematologic disorders. To facilitate reporting, we limited the items to only the basic data (underlying disease, age, sex), influenza-associated data (diagnostic method, therapy and outcome) and allowed space for free comments. We could share the information promptly, and found that this system worked well. One hundred and fifteen patients were reported between September 2009 and February 2010. Although eight patients needed to be hospitalized, none of the patients died, were admitted to intensive care units or demonstrated sequelae. The novel influenza A(H1N1) did not have a strong impact on pediatric patients with cancer or hematologic disorder at least during the 2009-2010 season.


Assuntos
Redes de Comunicação de Computadores , Doenças Hematológicas , Hospedeiro Imunocomprometido , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Sistemas de Informação , Neoplasias , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , Japão/epidemiologia , Masculino , Risco , Fatores Sexuais , Fatores de Tempo
5.
Jpn J Infect Dis ; 64(3): 177-82, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21617299

RESUMO

Pandemic influenza A (H1N1) virus (AH1pdm) emerged in April 2009. An inactivated, split-virus, unadjuvanted AH1pdm vaccine was manufactured in Japan, and vaccination was initiated with top priority for healthcare workers (HCWs) on October 19, 2009. A retrospective cohort study was conducted to evaluate the effectiveness of a single-dose vaccine for HCWs in a hospital in Japan. A total of 1,567 (84.5%) of 1,854 HCWs were vaccinated. Thirty-seven were infected with AH1pdm before the vaccine became available, and were excluded. The other 250 were not vaccinated for personal reasons. We analyzed the influenza infection rate with or without vaccination and related adverse events. Among the 1,817 HCWs without previous infection, 37 were infected with AH1pdm; 13 (5.2%) of 250 unvaccinated HCWs became infected, which was a significantly higher rate than the 24 (1.5%) of 1,567 vaccinated HCWs (P=0.001). Multivariate analysis revealed that age of 20-29 years was a risk factor for infection (adjusted odds ratio [aOR], 3.7; P<0.001), and that vaccination was a preventive factor (aOR, 0.20; P<0.001). Adverse events occurred in 549 of 1,060 HCWs, but most were mild. Although vaccination was carried out during AH1pdm epidemic expansion, the single-dose AH1pdm vaccine proved effective in HCWs, and severe adverse events were rare.


Assuntos
Pessoal de Saúde , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Adulto , Estudos de Coortes , Feminino , Hospitais Universitários , Humanos , Vacinas contra Influenza/administração & dosagem , Influenza Humana/imunologia , Japão , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Vacinação/efeitos adversos , Vacinação/métodos , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/efeitos adversos , Vacinas de Produtos Inativados/imunologia , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/efeitos adversos , Vacinas de Subunidades Antigênicas/imunologia , Adulto Jovem
6.
J Clin Virol ; 51(1): 68-72, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21324735

RESUMO

BACKGROUND: Definitive diagnosis is crucial in reducing morbidity and mortality from pandemic influenza A H1N1 2009 (A/H1N1/2009), especially in high-risk populations. We recently developed a rapid diagnosis kit (RDK) capable of specifically detecting A/H1N1/2009. OBJECTIVES: To evaluate the diagnostic capability of the RDK in a multicenter, prospective trial. STUDY DESIGN: Samples were obtained by nasal swab from patients with suspected influenza. The diagnostic capability of the RDK was compared with that of the standard, real-time reverse transcription-polymerase chain reaction (RT-PCR) method. RESULTS: Of 266 patients who met the criteria, 122 and 92 were positive for A/H1N1/2009 influenza by PCR and by the newly developed RDK, respectively. The sensitivity, specificity and positive and negative predictive values of the RDK were 73.0%, 97.9%, 96.7% and 81.0%, respectively. A/H1N1/2009 detection rates by the RDK were significantly lower in samples obtained from patients more than 3 days after onset than in samples obtained between 1 and 2 days. CONCLUSIONS: The A/H1N1/2009-specific RDK is a reliable test that can be used easily at a patient's bedside for rapid diagnosis of A/H1N1/2009. This test will be of key importance in the control of A/H1N1/2009.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos Virais/imunologia , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/diagnóstico , Kit de Reagentes para Diagnóstico/normas , Adolescente , Distribuição por Idade , Criança , Pré-Escolar , Cromatografia de Afinidade , Intervalos de Confiança , Feminino , Humanos , Lactente , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/imunologia , Influenza Humana/virologia , Japão , Masculino , Pandemias , Estudos Prospectivos , Kit de Reagentes para Diagnóstico/virologia , Sensibilidade e Especificidade , Distribuição por Sexo , Fatores de Tempo
7.
Microbiol Immunol ; 54(10): 618-24, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21118299

RESUMO

A phase III observational study evaluating a single-dose of an inactivated, split-virus, unadjuvanted AH1pdm vaccine in HCW was conducted. A safe and effective vaccine was needed after the emergence of AH1pdm in April 2009. We analyzed the immunogenicity and safety of the vaccine. A total of 409 subjects were enrolled and given 15 µg hemagglutinin antigen by s.c. injection. Antibody titers were measured using hemagglutination-inhibition antibody assays before vaccination and 28 days after. The co-primary immunogenicity end-points were the proportion of subjects with antibody titers of 1:40 or more, the proportion of subjects with either seroconversion or a significant increase in antibody titer, and the factor increase in geometric mean titer. We collected 389 pair samples. Antibody titers of 1:40 or more were observed in 148 of 389 subjects (38.0%, 95% CI: 33.2-42.9). The immunogenicity was also confirmed in other end-points, but was not sufficient and was lower than in previous reports. A total of 96 of adverse events was reported: 51 local events and 57 systemic events. There were 12 subjects with both local and systemic events. Nearly all events were mild to moderate except in four subjects. A single 15-µg dose of AH1pdm vaccine did not induce sufficient immunogenicity in HCW, with mild-to-moderate vaccine-associated adverse events. We need to consider further improvement of the AH1pdm vaccine program in HCW for the prevention of nosocomial infection, as well as for the benefit of HCW.


Assuntos
Pessoal de Saúde , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Adulto , Idoso , Anticorpos Antivirais/sangue , Feminino , Hospitais Universitários , Humanos , Vacinas contra Influenza/efeitos adversos , Japão , Masculino , Pessoa de Meia-Idade , Pandemias , Estudos Prospectivos , Vacinação
8.
Masui ; 59(1): 56-63, 2010 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-20077771

RESUMO

Infection control committee as the central decision-making and infection control team (ICT) for carrying out all aspects of infection control are important for hospital infection control. Standard precautions are used for all patients and apply to all body fluids except for sweat, whether or not they contain visible blood. Transmission-based precautions involve airborne, droplet, contact vector-borne and common vehicle precautions. Airborne precautions are for tuberculosis, varicella and measles. Small particles (< 5 microm) can be dispersed widely by air currents. Droplet precautions are for influenza, rubella, pertussis, and so on. Transmission via large droplet (< 5 microm) requires close contact within 1 to 2 m. Contact transmissions are for blood-borne pathogens, such as hepatitis B and C virus and HIV, bacterial infections via percutaneous and mucocutaneous exposure, and so on. Vaccinations for measles, rubella, varicella, mumps, influenza and hepatitis B virus to health-care workers are important. Influenza virus is mainly transmitted via droplet and contact, but also via airborne transmission in the aerosol-generating procedures such as intubation and suctioning. WHO declared a public health emergency in April 2009. A novel influenza has spread rapidly across the globe, and it will be necessary to prepare for the outbreak in this autumn and winter.


Assuntos
Controle de Infecções , Doenças Transmissíveis/microbiologia , Doenças Transmissíveis/transmissão , Busca de Comunicante , Surtos de Doenças/prevenção & controle , Hospitais , Humanos , Controle de Infecções/métodos , Controle de Infecções/organização & administração , Controle de Infecções/normas , Vacinação
9.
Clin J Gastroenterol ; 2(6): 420-424, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26192799

RESUMO

We report three cases of severe opportunistic infection in patients with acute liver failure (ALF). These cases included a 56-year-old man infected with Cryptococcus neoformans, cytomegarovirus (CMV), Candida albicans and Aspergillus fumigates, as well as a 62-year-old man and a 54-year-old woman infected with pneumocystis pneumonia, CMV and Aspergillus fumigatus. One patient died as a result of the infection rather than liver failure. We stress the importance of opportunistic infection as a consideration in the use of immunosuppressive agents for the treatment of ALF.

10.
Yakugaku Zasshi ; 128(7): 1073-9, 2008 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-18591876

RESUMO

The track records of the use of anti-methicillin-resistant Staphylococcus aureus agents (anti-MRSA agents) in a 5-year period (2001.4-2006.3) were collected, and cases in which anti-MRSA agents were used for >4 days were selected. In each case, the results of laboratory data and bacterial examination before and after administering the anti-MRSA agents were investigated retrospectively. In addition, it was also investigated in each case whether therapeutic drug monitoring (TDM) was carried out. It was observed that the number of patients treated with anti-MRSA agents and the total dose of anti-MRSA agents used tended to increase over time, except for arbekacin sulfate. It was, however, shown that treatment with anti-MRSA agents resulted in significant decreases in body temperature, C-reactive protein, and white blood cell counts. Bacterial examination was conducted in 75.6% of the patients treated with anti-MRSA agents, with MRSA being detected in 72.4% of the cases examined. On the other hand, TDM was also conducted in 60% of the cases, but this was at a lower percentage than that of the other examinations. Quantitative bacterial examination after treatment with anti-MRSA agents indicates that TDM can be considered important for the appropriate use of anti-MRSA agents.


Assuntos
Antibacterianos/administração & dosagem , Dibecacina/análogos & derivados , Monitoramento de Medicamentos , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Teicoplanina/administração & dosagem , Vancomicina/administração & dosagem , Antibacterianos/farmacologia , Dibecacina/administração & dosagem , Dibecacina/farmacologia , Farmacorresistência Bacteriana , Humanos , Resistência a Meticilina , Estudos Retrospectivos , Staphylococcus aureus/isolamento & purificação , Teicoplanina/farmacologia , Fatores de Tempo , Vancomicina/farmacologia
11.
Cell Biol Int ; 32(6): 692-7, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18295514

RESUMO

Phorbol-12-myristate-13-acetate (PMA) significantly elevated c-mpl promoter activity and the protein kinase C (PKC) inhibitors GF 109203, H7 and calphostin C conspicuously reduced the steady level of the activity. Destruction of the -107Sp1 and the -57Sp1 sites in the c-mpl promoter enhancer region resulted in decrease of the promoter activity by 49.6% and 48.2%, respectively, and destruction of -69Ets and -28Ets elements dramatically decreased the activity by 93.4% and 82.6%, respectively, while mutation of -77GATA moderately reduced the activity by 28.6%. We conclude that the expression of the c-mpl gene is modulated by transcription through a PKC-dependent pathway and that Ets elements at -69 and -28 nucleotides in front of the transcription start site are critical that Sp1(-107) and Sp1(-57) are also important and that GATA(-77) is less involved as a positive regulatory element in c-mpl gene expression induced by PMA in CMK cells.


Assuntos
Regiões Promotoras Genéticas , Receptores de Trombopoetina/genética , Acetato de Tetradecanoilforbol/farmacologia , Ativação Transcricional , Sítios de Ligação , Linhagem Celular , Elementos Facilitadores Genéticos , Humanos , Mutação Puntual , Proteína Quinase C/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-ets/metabolismo , Deleção de Sequência , Fator de Transcrição Sp1/metabolismo
12.
Ther Drug Monit ; 30(1): 75-83, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18223466

RESUMO

The objectives of this study were to develop a population pharmacokinetic model and to determine the covariates affecting the pharmacokinetics of busulfan in Japanese pediatric patients who received high-dose oral busulfan as a conditioning regimen before hematopoietic stem cell transplantation. Population analysis was performed using retrospective therapeutic drug monitoring data (including test dose data) from 103 children. Their ages ranged from 2 months to 11 years old (mean age, 30 months; median age, 18 months). The plasma concentration of busulfan in all 1028 samples was measured with the same high-performance liquid chromatography method. Maximum likelihood estimates were sought for pharmacokinetic parameters with the NONMEM program. The best structural covariate-free model for busulfan was a one-compartment model with an exponential error model to account for intersubject variability and a proportional error model to account for intrasubject variability. The apparent oral clearance was found to be correlated with age, aspartate transaminase, and type of disease (malignant disease or other). The apparent volume of distribution was related to body weight. The busulfan formulation (1% powder form or crystal form) and dose (milligrams per kilogram) influenced the absorption rate constant. It was estimated that oral clearance expressed per kilogram of body weight is low at early infancy, then increases to a maximum at approximately 2 years of age and, thereafter, decreases. In conclusion, we have developed a population pharmacokinetic model of oral busulfan in children, particularly for those younger than 4 years old, that takes into consideration not only body size, but also several other covariates.


Assuntos
Povo Asiático , Bussulfano/farmacocinética , Transplante de Células-Tronco Hematopoéticas , Imunossupressores/farmacocinética , Fatores Etários , Área Sob a Curva , Aspartato Aminotransferases/sangue , Bussulfano/sangue , Criança , Pré-Escolar , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Imunossupressores/sangue , Lactente , Japão , Masculino , Taxa de Depuração Metabólica , Modelos Biológicos
13.
Haematologica ; 92(12): 1687-90, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18055993

RESUMO

We analyzed the outcomes of 44 children with hepatitis associated aplastic anemia (HAA) who received immunosuppressive therapy (IST) with antithymocyte globulin (ATG) and cyclosporine (CsA). Fourteen (31.8%) patients achieved complete response and 17 (38.6%) achieved partial response, for an overall response rate of 70.4% after 6 months. Seven non-responders received bone marrow transplantation from an HLA-matched unrelated donor and 6 out of 7 are alive. The probability of overall survival at 10 years was 88.3+/-4.9%, which supports the role of IST with ATG and CsA as treatment of choice for children with HAA without an HLA identical sibling donor.


Assuntos
Anemia Aplástica/terapia , Soro Antilinfocitário/administração & dosagem , Transplante de Medula Óssea , Ciclosporina/administração & dosagem , Hepatite/terapia , Imunossupressores/administração & dosagem , Adolescente , Anemia Aplástica/mortalidade , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Seguimentos , Hepatite/patologia , Teste de Histocompatibilidade , Humanos , Lactente , Masculino , Taxa de Sobrevida , Transplante Homólogo
15.
Blood ; 104(12): 3527-34, 2004 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-15297313

RESUMO

Forty-four infants with acute lymphoblastic leukemia (ALL) characterized by MLL gene rearrangements were treated on a protocol of intensive chemotherapy followed by hematopoietic stem cell transplantation (HSCT) between November 1998 and June 2002. The remission induction rate was 91.0%, and the 3-year overall survival and event-free survival (EFS) rates, with 95% confidence intervals, were 58.2% (43.5%-72.9%) and 43.6% (28.5%-58.7%), respectively. Univariate analysis of EFS by presenting features indicated a poorer outcome in patients younger than 6 months of age with high white blood cell counts (>/= 100 x 10(9)/L; EFS rate, 9.4% versus 55.1% for all others, P = .0036) and in those with central nervous system invasion (EFS rate, 10.0% versus 56.9% for all others, P = .0073). The 3-year posttransplantation EFS rate for the 29 patients who underwent HSCT in first remission was 64.4% (46.4%-82.4%). In this subgroup, only the timing of HSCT (first remission versus others) was a significant risk factor by multivariate analysis (P < .0001). These results suggest that early introduction of HSCT, possibly with a less toxic conditioning regimen, may improve the prognosis for infants with MLL(+) ALL. Identification of subgroups or patients who respond well to intensified chemotherapy alone should have a high priority in future investigations.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Proteínas de Ligação a DNA/genética , Transplante de Células-Tronco Hematopoéticas/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Proto-Oncogenes/genética , Fatores de Transcrição/genética , Fatores Etários , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Feminino , Rearranjo Gênico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Histona-Lisina N-Metiltransferase , Humanos , Lactente , Recém-Nascido , Infiltração Leucêmica , Contagem de Leucócitos , Masculino , Proteína de Leucina Linfoide-Mieloide , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Prognóstico , Indução de Remissão , Análise de Sobrevida , Condicionamento Pré-Transplante/efeitos adversos , Resultado do Tratamento
16.
J Gravit Physiol ; 11(2): P65-6, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16231458

RESUMO

We have analyzed the effect of stress caused by the exposure of BALB/c mice to microgravity change on the susceptibility to herpes simplex virus type 1 (HSV-1) infection. Mice exposed to microgravity for 10 seconds showed a decreased rate of survival from HSV-1 infection. Murine interferon (MuIFN) administration to mice after exposure to microgravity partly diminished the decrease in survival. After repeated exposure to microgravity, mice showed tolerance to the stress. These results indicate that microgravity-stress leads to a down regulation of resistance to virus infection in relation to the modulation of the central nerve system in mice. Responsibility of the immune system dependent on cytokines, including IFN, for down regulation of the resistance is also suggested. Tail-suspended mice were also less resistant to virus infection.


Assuntos
Herpes Simples/imunologia , Imunidade Inata/efeitos dos fármacos , Interferon-alfa/farmacologia , Interferon beta/farmacologia , Estresse Fisiológico/imunologia , Simulação de Ausência de Peso , Adaptação Fisiológica/imunologia , Animais , Feminino , Elevação dos Membros Posteriores , Camundongos , Camundongos Endogâmicos BALB C
17.
J Biol Chem ; 278(33): 30450-7, 2003 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12750384

RESUMO

Genes expressed with day/night rhythms in the mouse liver were searched for by microarray analysis using an in-house array harboring mouse liver cDNAs. The rhythmic expression with a single peak and trough level was confirmed by RNA blot analysis for 3beta-Hsd and Gabarapl1 genes exhibiting a peak in the light phase and Spot14, Hspa8, Hspa5, and Hsp84-1 genes showing a peak in the dark phase. On the other hand, mRNA levels for all of the three fibrinogen subunits, Aalpha, Bbeta and gamma, exhibited two peaks each in the light and dark phases in a synchronized manner. This two-peaked rhythmic pattern of fibrinogen genes as well as the single peak-trough pattern of other genes was diminished or almost completely lost in the liver of Clock mutant mice, suggesting that the two-peaked expression is also under the control of oscillation-generating genes. In constant darkness, the first peak of the expression rhythm of fibrinogen genes was almost intact, but the second peak disappeared. Therefore, although the first peak in the subjective day is a component of the innate circadian rhythm, the second peak seems to require light stimuli. Fasting in constant darkness caused shifts of time phases of the circadian rhythms. Protein levels of the fibrinogen subunits in whole blood also exhibited circadian rhythms. In the mouse and human loci of the fibrinogen gene cluster, a number of sequence elements resembling circadian transcription factor-binding sites were found. The fibrinogen gene locus provides a unique system for the study of two-peaked day/night rhythms of gene expression in a synchronized form.


Assuntos
Ritmo Circadiano/fisiologia , Fibrinogênio/genética , Fígado/fisiologia , Animais , Mapeamento Cromossômico , Cromossomos de Mamíferos , Chaperona BiP do Retículo Endoplasmático , Regulação da Expressão Gênica/fisiologia , Masculino , Camundongos , Família Multigênica/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos
18.
J Biol Chem ; 277(13): 11247-54, 2002 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-11782470

RESUMO

Expression levels of Gb3/CD77 synthase together with Gb3/CD77 antigen were analyzed using human hematopoietic tumor cell lines and normal cells. Among about 40 kinds of cells, Burkitt lymphoma cells showed the highest gene expression concomitant with the expression levels of Gb3/CD77. Unexpectedly, megakaryoblastic leukemia lines also expressed fairly high levels of mRNA of Gb3/CD77 synthase and its product. A megakaryoblastic leukemia line, MEG-01 was sensitive to verotoxins from Escherichia coli O157 and apoptosis was induced via the caspase pathway. We also demonstrated that the cell surface Gb3/CD77 expression was reduced on differentiated MEG-01 although the mRNA level of the alpha1,4Gal-T gene increased. In this case, the localization of Gb3/CD77 was changed from the cell surface to the cytoplasm as stained with a granular pattern, co-localizing with platelet GPIIb-IIIa, indicating that some of them were platelet precursors. Small particles outside of cells also showed similar staining patterns. These results agreed with the previous report that platelets produced in mature megakaryoblasts abundantly contained Gb3/CD77 antigen. Here, we propose the possibility that verotoxins bind immature megakaryoblasts and induce their apoptosis, leading to the arrest of platelet generation in the bone marrow. This may be one of the causes of thrombocytopenia in patients with hemolytic uremic syndrome.


Assuntos
Galactosiltransferases/genética , Leucemia Megacarioblástica Aguda/genética , Toxinas Shiga/farmacologia , Apoptose , Humanos , Leucemia Megacarioblástica Aguda/enzimologia , Leucemia Megacarioblástica Aguda/patologia , Células Tumorais Cultivadas
19.
Biol Sci Space ; 16(3): 159-60, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12695601

RESUMO

It is reported that the stay in the space develop anemia, throbocytopenia, and altered function and structure of red blood cell. The mechanism of these abnormalities was not clarified yet. TPO has been shown to stimulate both megakaryocyte colony growth from marrow progenitor cells and the maturation of immature megakaryocyte to form functional platelet. This process include massive cytoskeletal rearrangement, such as proplatelet formation and fragmentation of proplatelet. Our previous reports (Fuse and Sato, 2001, Fuse et al, 2001) showed an inverse relationship between decreased platelet count and increased TPO concentrations in peripheral blood of mouse was induced by parabolic flight (PF). We have studied which gravity change during PF involved this phenomenon.


Assuntos
Plaquetas/fisiologia , Hipergravidade , Voo Espacial , Trombocitopenia/etiologia , Ausência de Peso/efeitos adversos , Animais , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Contagem de Plaquetas , Trombopoetina/sangue , Trombopoetina/metabolismo , Fatores de Tempo
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