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1.
Eur J Clin Microbiol Infect Dis ; 36(9): 1651-1660, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28409290

RESUMO

Viral meningitis is mainly caused by non-polio enteroviruses (NPEV). Large-scale data on the clinical characteristics between different outbreaks within the same region are lacking. This study aimed to analyse a possible influence of the circulating NPEV genotype on the disease outcome of affected children. A retrospective cohort study analysing two major outbreaks of NPEV meningitis in Germany in 2008 and 2013 was conducted in cooperation with the National Reference Centre for Poliomyelitis and Enteroviruses (NRC PE) and five German children's hospitals. A total of 196 patients with laboratory-confirmed NPEV meningitis were enrolled. In 2008, children with NPEV meningitis had significantly higher fever and showed more behavioural changes and less back pain. To better define typical findings in echovirus 30 (E-30) meningitis, patients were split into the following three groups: E-30 positive patients, patients with "Non E-30" infection and patients with "Untyped" NPEV infection. E-30 positive patients were significantly older and their disease course was more acute, with early admission to but also early discharge from hospital. E-30 positive patients showed a significantly higher rate of headache and meningism, and a lower rate of diarrhoea and clinically defined septicaemia when compared to the others. Regarding laboratory testing, E-30 positive patients presented with significantly elevated peripheral blood neutrophil counts when compared to patients with "Non E-30" or "Untyped" NPEV infection. In conclusion, E-30 meningitis in children shows a characteristic pattern of clinical features. To further characterise NPEV strains worldwide, continuous surveillance and typing of NPEV strains causing central nervous system disease is warranted.


Assuntos
Surtos de Doenças , Enterovirus Humano B , Enterovirus , Meningite Viral/epidemiologia , Meningite Viral/virologia , Criança , Pré-Escolar , Enterovirus/classificação , Enterovirus Humano B/classificação , Feminino , Alemanha/epidemiologia , História do Século XXI , Humanos , Masculino , Meningite Viral/diagnóstico , Meningite Viral/história , Admissão do Paciente/estatística & dados numéricos , Estudos Retrospectivos , Sorogrupo , Avaliação de Sintomas
2.
Allergol Select ; 1(1): 21-27, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30402598

RESUMO

Food allergens are frequent causes of anaphylaxis. In particular in children and adolescents they are the most frequent elicitors of severe allergic reactions, and in adults food allergens rank third behind insect venom and drugs. Since July 2006 severe allergic reactions from Germany, Austria, and Switzerland are collected in the anaphylaxis registry. Currently 78 hospitals and private practises are connected. From July 2006 until February 2009 1,156 severe allergic reactions were registered. Among children and adolescents (n = 187, age range from 3 months to 17 years) food allergens were the most frequent triggers, comprising 58% of cases. In the adult group (n = 968, 18 - 85 years) food allergens were in the third position (16.3%) behind insect venom and drugs. In children legumes (31%) and in particular peanuts were frequently responsible food allergens, followed by tree nuts (25%) with hazelnut being the most frequent elicitor. In adults fruits (13.4%) most often induced severe food-dependent anaphylaxis, but also animal products (12.2%); among these most frequently crustaceans and molluscs. Cofactors were often suspected in food-dependent anaphylaxis, namely in 39% of the adult group and in 14% of the pediatric group. In adults drugs (22%) and physical activity (10%) were reported to be the most frequent cofactors, in children physical activity was suspected in 8.7% and drugs in 2.6%. Concomitant diseases like atopic dermatitis, allergic asthma, or allergic rhinoconjunctivitis were reported in 78% of children and adolescents and in 67% of the adults. In conclusion, food-induced anaphylaxis, its cofactors and concomitant diseases are age-dependent. The data offers to identify risk factors of anaphylaxis.

3.
Eur J Clin Microbiol Infect Dis ; 31(11): 3173-82, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22850740

RESUMO

A prospective clinical study was performed to correlate nasopharyngeal carriage of bacteria with the type of lower respiratory tract infections (LRTI) in hospitalised children. To determine bacterial load in nasopharyngeal aspirates (NPA) we used semiquantitative culturing and quantitative TaqMan-PCR for those pathogens difficult to culture. Specimens and clinical data were obtained from 311 children between 0 and 16 years of age with LRTI during the period of 2006-2008. The most common detected potentially pathogenic colonisers were Haemophilus influenzae (32.1 %), Moraxella catharralis (26.7 %), Staphylococcus aureus (17.7 %) and Streptococcus pneumoniae (16.7 %). As expected S. aureus was the most common coloniser in children less than 4 months of age, whereas H. influenzae detection peaked in older children. Co-colonisation with other bacterial pathogens were more often observed in children with S. aureus (46 %) and S. pneumoniae (49 %) than in those with H. influenzae (30 %) or M. catharralis (27 %). Children with S. aureus co-colonisation had higher levels of C-reactive-protein, received antibiotics more frequently and stayed longer in hospital than those with S. aureus single colonisation. In contrast, children with H. influenzae, M. catharralis or S. pneumoniae colonisation suffered more often from pneumonia than children with S. aureus colonisation. Coloniser specific analysis of bacterial quantity revealed no significant reduction of the bacterial carriage from the first to the second NPA. No correlation of a high bacterial load and occurrence of pneumonia could be detected. In conclusion, clinical characteristics in children with LRTIs are associated with a specific bacterial set of colonisers detected in the nasopharynx rather than on their quantity.


Assuntos
Bactérias/classificação , Bactérias/isolamento & purificação , Infecções Bacterianas/patologia , Portador Sadio/microbiologia , Nasofaringe/microbiologia , Infecções Respiratórias/patologia , Adolescente , Infecções Bacterianas/microbiologia , Carga Bacteriana/métodos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Reação em Cadeia da Polimerase/métodos , Estudos Prospectivos , Infecções Respiratórias/microbiologia
4.
J Surg Oncol ; 102(5): 539-42, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20812264

RESUMO

Bevacizumab (Avastin™; rhuMab VEGF), a monoclonal antibody targeting vascular endothelial growth factor (VEGF), has seen increased use in the perioperative treatment of colorectal and pancreatic cancer. Little is known, however, regarding its impact on surgical outcomes in patients undergoing resection. The objective of this review was to examine if the addition of bevacizumab to existing neoadjuvant regimens increases morbidity after cancer resection.


Assuntos
Inibidores da Angiogênese/efeitos adversos , Anticorpos Monoclonais/efeitos adversos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Inibidores da Angiogênese/administração & dosagem , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados , Bevacizumab , Neoplasias Colorretais/cirurgia , Humanos , Terapia Neoadjuvante , Neoplasias Pancreáticas/cirurgia , Complicações Pós-Operatórias , Resultado do Tratamento
5.
Crit Rev Oncol Hematol ; 58(2): 156-65, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16387511

RESUMO

Anemia is common in older people and it becomes more so with advancing decades. Because the older population is increasing, the prevalence of anemia and consequently its impact on health and healthcare expenditure is expected to rise. Although the causes and consequences of anemia have not been fully elucidated and its etiology is occasionally elusive, clinical evidence has indicated that anemia itself is a cause of morbidity and it can complicate other health conditions. The clinical approach to anemia is evolving. In the past, anemia was mainly seen as a sign of underlying disease; today, anemia is considered to be a cause of severe deterioration of quality of life, morbidity, and decline in physical function, and a risk factor for death. A better understanding of anemia in the elderly will lead to improved treatment strategies, including the more judicious use of transfusion and appropriate use of erythropoietic agents.


Assuntos
Anemia/epidemiologia , Avaliação Geriátrica , Serviços de Saúde para Idosos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/economia , Doença de Alzheimer/etiologia , Anemia/complicações , Anemia/economia , Anemia/terapia , Doenças Cardiovasculares/economia , Doenças Cardiovasculares/etiologia , Doença Crônica , Fadiga/economia , Fadiga/etiologia , Feminino , Custos de Cuidados de Saúde , Humanos , Masculino , Prevalência , Fatores de Risco , Análise de Sobrevida
6.
Blood ; 97(11): 3424-32, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11369633

RESUMO

The retinoblastoma (Rb), cyclin-dependent kinase (CDK), and CDK inhibitor genes regulate cell generation, and deregulation can produce increased cell growth and tumorigenesis. Polycythemia vera (PV) is a clonal myeloproliferative disease where the mechanism producing increased hematopoiesis is still unknown. To investigate possible defects in cell-cycle regulation in PV, the expression of Rb and CDK inhibitor gene messenger RNAs (mRNAs) in highly purified human erythroid colony-forming cells (ECFCs) was screened using an RNase protection assay (RPA) and 11 gene probes. It was found that RNA representing exon 2 of p16(INK4a) and p14(ARF) was enhanced by 2.8- to 15.9-fold in 11 patients with PV. No increase of exon 2 mRNA was evident in the T cells of patients with PV, or in the ECFCs and T cells from patients with secondary polycythemia. p27 also had elevated mRNA expression in PV ECFCs, but to a lesser degree. Because the INK4a/ARF locus encodes 2 tumor suppressors, p16(INK4a) and p14(ARF) with the same exon 2 sequence, the increased mRNA fragment could represent either one. To clarify this, mRNA representing the unique first exons of INK4a and ARF were analyzed by semiquantitative reverse transcription-polymerase chain reaction. This demonstrated that mRNAs from the first exons of both genes were increased in erythroid and granulocyte-macrophage cells and Western blot analysis showed that the INK4a protein (p16(INK4a)) was increased in PV ECFCs. Sequencing revealed no mutations of INK4a or ARF in 10 patients with PV. p16(INK4a) is an important negative cell-cycle regulator, but in contrast with a wide range of malignancies where inactivation of the INK4a gene is one of the most common carcinogenetic events, in PV p16( INK4a) expression was dramatically increased without a significant change in ECFC cell cycle compared with normal ECFCs. It is quite likely that p16(INK4a) and p14(ARF) are not the pathogenetic cause of PV, but instead represent a cellular response to an abnormality of a downstream regulator of proliferation such as cyclin D, CDK4/CDK6, Rb, or E2F. Further work to delineate the function of these genes in PV is in progress. (Blood. 2001;97:3424-3432)


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/genética , Quinases Ciclina-Dependentes/antagonistas & inibidores , Expressão Gênica , Policitemia Vera/genética , Proteínas/genética , Idoso , Ciclo Celular , Divisão Celular , Análise Mutacional de DNA , Células Precursoras Eritroides/metabolismo , Células Precursoras Eritroides/patologia , Éxons , Feminino , Granulócitos/química , Células-Tronco Hematopoéticas/química , Humanos , Macrófagos/química , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T/química , Linfócitos T/metabolismo , Proteína Supressora de Tumor p14ARF
7.
Glycoconj J ; 18(10): 769-77, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12441666

RESUMO

An affinity purification procedure is employed for the isolation of FL-specific binding proteins from MM6 cell membranes using magnetobeads coated with glycated polylysine and elution with FL and glycated 6-aminocaproic acid. Two main binding proteins were identified as membrane-bound nucleolin and cellular myosin heavy chain, which are glycosylated. This study shows that in these cells binding of short-term glycated albumin leads to activation of PKC, especially its isoform epsilon and this is linked to translocation of AP-1 and NF-kappaB into the nucleus. Consequently, an increased formation of IL-1ss mRNA is observed. The PKC inhibitor GO6976 prevents all these effects. Glycated albumin also stimulates activation of PTK. The PTK inhibitor genistein prevents activation of AP-1 indicating that PTK is also involved in this process, whereas NF-kappaB translocation is only dependent on PKC activation.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular , Isoenzimas/metabolismo , Monócitos/metabolismo , NF-kappa B/metabolismo , Proteína Quinase C/metabolismo , Albumina Sérica/metabolismo , Fator de Transcrição AP-1/metabolismo , Proteínas de Transporte/farmacologia , Linhagem Celular , Citocinas/biossíntese , Ensaio de Desvio de Mobilidade Eletroforética , Ativação Enzimática , Produtos Finais de Glicação Avançada , Glicosilação , Humanos , Proteínas de Membrana/química , Proteínas de Membrana/isolamento & purificação , Proteínas de Membrana/metabolismo , Monócitos/enzimologia , Cadeias Pesadas de Miosina/química , Cadeias Pesadas de Miosina/isolamento & purificação , Cadeias Pesadas de Miosina/metabolismo , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Ligação Proteica , Proteína Quinase C-épsilon , RNA Mensageiro/biossíntese , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Albumina Sérica/química , Albumina Sérica/farmacologia , Transdução de Sinais , Albumina Sérica Glicada , Nucleolina
8.
Blood ; 97(4): 843, 2001 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11873810
9.
Eur J Pediatr ; 159 Suppl 2: S70-3, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11043148

RESUMO

UNLABELLED: Phenylketonuria treatment policies vary not only between different countries worldwide, but also within one country. Recommendations and guidelines for phenylketonuria should deal with the following subjects: 1. What is the target age to start dietary phenylalanine restriction under newborn-screening conditions? 2. At which plasma phenylalanine concentration should phenylalanine restriction be initiated? 3. Which are the recommended plasma phenylalanine concentrations at different ages? 4. What is the recommended frequency of monitoring phenylalanine in plasma? Statements from the following countries are presented: Czech Republic, Denmark, France, Germany, Great Britain, Hungary, Ireland, Poland, Slovakia and the United States. CONCLUSION: Due to the lack of internationally accepted guidelines, management of phenylketonuria still varies between different countries. Our efforts should focus on the formulation of internationally acceptable and accepted recommendations for the treatment of patients with phenylketonuria at different ages.


Assuntos
Fenilcetonúrias/dietoterapia , Guias de Prática Clínica como Assunto , Adolescente , Adulto , Envelhecimento/sangue , Criança , Pré-Escolar , Coleta de Dados , Europa (Continente) , Humanos , Lactente , Recém-Nascido , Fenilalanina/administração & dosagem , Fenilalanina/sangue , Fenilcetonúrias/sangue , Fatores de Tempo , Estados Unidos
11.
Br J Haematol ; 110(1): 63-70, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10930980

RESUMO

Erythropoietin (EPO) and stem cell factor (SCF) are two important factors in human erythropoiesis. We have recently demonstrated that SCF and EPO synergistically activate mitogen-activated protein (MAP) kinase, thereby promoting growth of human erythroid colony-forming cells (ECFCs). In the present study, we have examined the intracellular mechanisms by which SCF and EPO maintain survival of these cells. In the absence of SCF and EPO, human ECFCs underwent rapid apoptosis. The process was significantly inhibited by addition of a single factor and was totally prevented in the presence of both factors. Treatment of ECFCs with wortmannin, a specific inhibitor of phosphoinositide 3-kinase (PI3K), inhibited the antiapoptotic effect of SCF but had no effect on that of EPO, indicating that SCF but not EPO inhibits apoptosis through the PI3K pathway. In contrast, treatment of ECFCs with PD98059, a specific inhibitor of MAP kinase/ERK kinase (MEK), inhibited cell growth but had no effect on the antiapoptotic activity of either SCF or EPO, suggesting that SCF and EPO prevent apoptosis of human ECFCs independent of the extracellular signal-regulated kinase (ERK) pathway. Interestingly, both EPO and SCF induced activation of PI3K. However, through PI3K, SCF caused activation of protein kinase B (PKB), an anti-apoptosis signal, whereas EPO led to activation of ERKs. Furthermore, the SCF- and EPO-maintained expression of antiapoptotic protein Bcl-XL was correlated with the activation of ERKs and was inhibited by PD98059, suggesting that Bcl-XL may not have a major role in preventing apoptosis of human ECFCs. Phosphorylated BAD was not affected by SCF, EPO or wortmannin. Taken together with our previous results, the present study indicates that SCF and EPO support survival and growth of human ECFCs through different signalling pathways and that they transduce distinctly different signals through activation of PI3K.


Assuntos
Apoptose/efeitos dos fármacos , Células Precursoras Eritroides/fisiologia , Eritropoetina/farmacologia , Proteínas Serina-Treonina Quinases , Transdução de Sinais , Fator de Células-Tronco/farmacologia , Androstadienos/farmacologia , Células Cultivadas , Sinergismo Farmacológico , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Células Precursoras Eritroides/efeitos dos fármacos , Flavonoides/farmacologia , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Wortmanina
12.
Blood ; 95(12): 3742-9, 2000 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10845905

RESUMO

Based on the hypothesis that interferon gamma (IFN-gamma) may have stimulating effects on survival of hematopoietic progenitor cells, we examined the effect of IFN-gamma on apoptosis of mature erythroid colony-forming cells (ECFCs) derived from human peripheral blood obtained from normal, healthy volunteers. When the cells were cultured in the presence of IFN-gamma, even without erythropoietin (EPO), the viability of the cells was maintained for at least 36 hours. When apoptosis of ECFCs was assessed by flow cytometric analysis', using annexin V, IFN-gamma reduced the extent of apoptosis of the cells, as well as EPO. DNA fragmentation of ECFCs was also reduced by IFN-gamma. In cells cultured with IFN-gamma alone, expression of Bcl-x was detected but the level of expression decreased gradually during incubation for 36 hours, and the expression level was lower than incubation with EPO. Fas expression and activation of downstream caspases were assessed by flow cytometric analysis or fluorometric protease assay. IFN-gamma induced Fas expression of the cells without the activation of caspase8 or caspase3 during 16 hours of incubation, while deprivation of EPO induced expression of Fas and the activation of both caspase8 and caspase3. We propose that IFN-gamma produces a stimulating signal for the survival of mature erythroid progenitor cells by reducing apoptosis through a mechanism other than modulating Fas and one related to the expression of Bcl-x. (Blood. 2000;95:3742-3749)


Assuntos
Apoptose/fisiologia , Eritropoetina/farmacologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/fisiologia , Interferon gama/farmacologia , Anexina A5/análise , Apoptose/efeitos dos fármacos , Caspase 3 , Caspase 8 , Caspase 9 , Caspases/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultura Livres de Soro , Fragmentação do DNA , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Interleucina-3/farmacologia , Cinética , Proteínas Proto-Oncogênicas c-bcl-2/análise , Proteínas Recombinantes/farmacologia , Fator de Células-Tronco/farmacologia
13.
J Pediatr Health Care ; 14(1): 20-5, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11141822

RESUMO

INTRODUCTION: The purpose of this study was to retrospectively ascertain behaviors and activities that may constitute high risk during the adolescent years (ages 12-18) of young adults (ages 20-25) who are infected with human immunodeficiency virus (HIV). METHODS: Subjects (n = 44) from 1 of 5 clinics in a large midwestern city completed a survey form, developed by the investigators, which examined 6 areas of behavior and activities that the literature suggested may be associated with high-risk behaviors. RESULTS: The adolescent high-risk profile of an HIV-infected young man includes sexual abuse before the age of 12 years, heavy consumption of alcohol, heavy consumption of a variety of illicit drugs, a wide variety of sexual experiences at very young ages, and multiple sexual partners. The adolescent high-risk profile of an HIV-infected young woman in this study includes heavy consumption of alcohol, heavy consumption of a variety of illicit drugs, and unprotected vaginal intercourse at very young ages as evidenced by a high number of sexually transmitted diseases at very young ages. DISCUSSION: Although the small number of participants in this study restricts interpretation of the results, adolescent health initiatives should be examined in light of these findings. Programs and services must consider the context of psychosocial situations, as well as past experiences, and incorporate this knowledge into prevention strategies.


Assuntos
Comportamento do Adolescente , Infecções por HIV/prevenção & controle , Infecções por HIV/psicologia , Assunção de Riscos , Adolescente , Adulto , Criança , Coleta de Dados , Feminino , Humanos , Masculino , Estudos Retrospectivos , População Urbana
16.
Glycoconj J ; 17(10): 713-6, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11425191

RESUMO

Amadori-modified proteins are bound by macrophages and monocytes via fructosyllysine-specific receptors. Detergent extracts from U937 cell membranes were used to purify the binding proteins by affinity purification on glycated polylysine coated magnetic beads followed by SDS-PAGE. Two proteins of 200 and 100kDa were isolated. MS-analysis of the 200 kDa protein showed high homologies with cellular myosin heavy chain, type A. Both fructosyllysine specific binding proteins, cellular myosin heavy chain and nucleolin, are glycosylated.


Assuntos
Proteínas de Membrana/isolamento & purificação , Proteínas de Membrana/metabolismo , Proteínas Motores Moleculares , Cadeias Pesadas de Miosina/isolamento & purificação , Cadeias Pesadas de Miosina/metabolismo , Sequência de Aminoácidos , Glicosilação , Humanos , Proteínas de Membrana/química , Dados de Sequência Molecular , Cadeias Pesadas de Miosina/química , Proteínas Nucleares , Fosfoproteínas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Células U937 , Nucleolina
17.
Blood ; 94(12): 4067-76, 1999 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-10590051

RESUMO

Erythropoietin (EPO), a major regulator of erythroid progenitor cells, is essential for the survival, proliferation, and differentiation of immature erythroid cells. To gain insight into the molecular mechanism by which EPO functions, we analyzed the activation of Jun N-terminal kinases (JNKs) and extracellular signal-regulated kinases (ERKs) in HCD-57 cells, a murine erythroid progenitor cell line that requires EPO for survival and proliferation. Withdrawal of EPO from the cell culture medium resulted in sustained activation of JNKs plus p38 MAP kinase, and inactivation of ERKs, preceding apoptosis of the cells. Addition of EPO to the EPO-deprived cells caused activation of ERKs accompanied by inactivation of JNKs and p38 MAP kinase and rescued the cells from apoptosis. Phorbol 12-myristate 13-acetate, which activated ERKs by a different mechanism, also suppressed the activation of JNKs and significantly retarded apoptosis of the cells caused by withdrawal of EPO. Furthermore, MEK inhibitor PD98059, which inhibited activation of ERKs, caused activation of JNKs, whereas suppression of JNK expression by antisense oligonucleotides and inhibition of p38 MAP kinase by SB203580 caused attenuation of the apoptosis that occurs upon withdrawal of EPO. Finally, the activation of JNKs and p38 MAP kinase and concurrent inactivation of ERKs upon withdrawal of EPO were also observed in primary human erythroid colony-forming cells. Taken together, the data suggest that activation of ERKs promotes cell survival, whereas activation of JNKs and p38 MAP kinase leads to apoptosis and EPO functions by controlling the dynamic balance between ERKs and JNKs.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Eritroblastos/patologia , Eritroblastos/fisiologia , Eritropoetina/farmacologia , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Animais , Linhagem Celular , Sobrevivência Celular/fisiologia , Humanos , Sistema de Sinalização das MAP Quinases/fisiologia , Camundongos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Proteínas Quinases p38 Ativadas por Mitógeno
18.
J Clin Immunol ; 19(3): 179-85, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10404403

RESUMO

The cytokines, interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), and interleukin-2 (IL-2) are important endogenous proinflammatory proteins and have been linked to disease activity in multiple sclerosis. In this study, we use flow cytometric methodology to compare the secretion of IFN-gamma, IL-2, and TNF-alpha from peripheral blood-derived T cells of multiple sclerosis patients to the secretion in healthy controls. The percentages of IFN-gamma, IL-2, and TNF-alpha secreting cells are not significantly different between multiple sclerosis patients and controls. However, the TNF-alpha secreting CD3 cell percentage is correlated with the IFN-gamma and IL-2 secreting CD3 cell percentages in multiple sclerosis patients. In the controls, only the TNF-alpha secreting CD3 cell percentage is correlated with IFN-gamma. These findings show that correlated secretion of cytokines occurs in multiple sclerosis and suggest that concerted intercytokine interactions may play an important role in the disease.


Assuntos
Citocinas/biossíntese , Esclerose Múltipla/imunologia , Linfócitos T/imunologia , Adolescente , Adulto , Idoso , Complexo CD3/metabolismo , Citocinas/sangue , Feminino , Citometria de Fluxo , Humanos , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade
19.
Blood ; 93(10): 3309-16, 1999 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10233883

RESUMO

Interferon gamma (IFNgamma) induces apoptosis in purified human erythroid colony-forming cells (ECFC) and inhibits cell growth. Fas (APO-1; CD95) and Fas ligand (FasL) mediate apoptosis induced by IFNgamma, because Fas is significantly upregulated by IFNgamma, whereas Fas ligand is constitutively present in the ECFC and neutralization of FasL greatly reduces the apoptosis. Because conversion of caspases from their dormant proenzyme forms to active enzymes has a critical role in transducing a cascade leading to apoptosis, we performed further studies of the expression and activation of caspases in normal human and IFNgamma-treated day-6 ECFC to better understand the mechanism of IFNgamma action in producing this cell death. RNase protection assays showed that the caspase-1, -2, -6, -8, and -9 mRNAs were upregulated by IFNgamma, whereas the caspase-5 and -7 mRNAs were not increased. Western blots showed that FLICE/caspase-8 was upregulated and activated by 24 hours of incubation with IFNgamma. FADD was not similarly altered by incubation with IFNgamma. Western blots of ICE/caspase-1, which might be required for amplification of the initial FLICE activation signal, showed that pro-ICE expression significantly increased after treatment with IFNgamma for 24 hours and cleavage of pro-ICE also increased. CPP32/apopain/caspase-3, responsible for the proteolytic cleavage of poly (ADP) ribose polymerase (PARP), was also studied and treatment of ECFC with IFNgamma resulted in an increased concentration of caspase-3 by 24 hours and a clear induction of enzyme activation by 48 hours, which was identified by the appearance of its p17-kD peptide fragment. The cleavage of PARP was demonstrated by an obvious increase of the 89-kD PARP cleavage product, which was observed at almost the same time as caspase-3 activation in the IFNgamma-treated cells, whereas untreated ECFC showed little change. Peptide inhibitors of the caspase proteins, DEVD-fmk, DEVD-cho, YVAD-cho, and IETD-fmk, were incubated with the ECFC to obtain further evidence for the involvement of caspases in IFNgamma-induced apoptosis. The activation of FLICE/caspase-8 and CPP32/caspase-3 and cleavage of PARP clearly were inhibited, but the reduction of cell growth due to apoptosis, induced by IFNgamma, was only partially blocked by the presence of the inhibitors. These results indicate that IFNgamma acts on ECFC not only to upregulate Fas, but also to selectively upregulate caspases-1, -3, and -8, which are activated and produce apoptosis, whereas the concentrations of FasL and FADD are not demonstrably changed.


Assuntos
Caspase 1/genética , Caspases/genética , Células Precursoras Eritroides/citologia , Células Precursoras Eritroides/fisiologia , Regulação Enzimológica da Expressão Gênica , Interferon gama/farmacologia , Apoptose/efeitos dos fármacos , Caspase 1/metabolismo , Caspase 3 , Caspase 8 , Caspase 9 , Caspases/metabolismo , Separação Celular/métodos , Células Cultivadas , Inibidores de Cisteína Proteinase/farmacologia , Ativação Enzimática , Células Precursoras Eritroides/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Cinética , RNA Mensageiro/genética , Proteínas Recombinantes , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos
20.
Ann Occup Hyg ; 42(8): 541-7, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9838867

RESUMO

A new whole-body exposure chamber for human skin and lung challenge offers possibilities for experimental exposure challenges carried out in clinical practice, for exposure of patients, in research and for investigations of the effects of exposure on the skin and in the respiratory tract. The chamber system can be used for both aerosols and gases. Dynamically controlled, the chamber is relatively easy to operate and to clean. Air exchange rates can be varied between 6-12/h. Initial studies with wheat flour have been carried out. The homogeneity and stability of the wheat flour aerosol concentration (the spatial and the temporal variation) inside the chamber can be kept at acceptable levels.


Assuntos
Aerossóis/efeitos adversos , Câmaras de Exposição Atmosférica , Farinha/efeitos adversos , Exposição Ocupacional , Triticum , Administração Cutânea , Aerossóis/farmacocinética , Aerossóis/farmacologia , Humanos , Exposição por Inalação , Pulmão/efeitos dos fármacos , Sistema Respiratório/efeitos dos fármacos , Pele/efeitos dos fármacos
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