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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.
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
3.
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
4.
J Clin Invest ; 91(2): 416-9, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8432849

RESUMO

We have previously reported that inhibition of human CFU-erythroid (E) colony formation by tumor necrosis factor (TNF) is an indirect effect mediated by a soluble factor released from a fraction of marrow accessory cells which are predominantly stromal elements (Means, R. T., Jr., E. N. Dessypris, and S. B. Krantz. 1990. J. Clin. Invest. 86:538-541). Further studies reported here identify a mediator of this effect. The inhibitory effect of recombinant TNF on marrow CFU-E is ablated by neutralizing antibodies to human beta IFN, but not by antibodies to gamma IFN or IL-1. Anti-beta IFN also neutralizes the inhibitory effect of conditioned medium prepared from marrow cells exposed to TNF. Human beta IFN inhibits colony formation by unpurified marrow CFU-E as well as highly purified CFU-E generated from peripheral blood progenitors, and limiting dilution analysis shows that this is a direct inhibitory effect. TNF has been implicated in the pathogenesis of the anemia of chronic diseases since blood TNF levels are elevated in many patients with this syndrome, and since exposure to TNF produces a similar anemia in either humans or mice. The present study demonstrates that beta IFN is a required mediator of this inhibitory effect on erythropoiesis.


Assuntos
Células Precursoras Eritroides/efeitos dos fármacos , Interferon beta/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Eritropoese/efeitos dos fármacos , Humanos , Técnicas In Vitro , Proteínas Recombinantes/farmacologia
5.
J Clin Invest ; 86(2): 538-41, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2384599

RESUMO

Recombinant tumor necrosis factor (rTNF) inhibits erythropoiesis in vivo and in vitro. To study the mechanism of this inhibition, the effect of rTNF on highly purified human CFU-erythroid (E) (mean purity 63.5%), which were generated from peripheral blood burst-forming units-erythroid (BFU-E), was compared to its effect on unpurified human marrow CFU-E (mean purity 0.21%). Although growth of colonies from marrow CFU-E was inhibited by rTNF, no significant effect on purified BFU-E-derived CFU-E colony growth was found. Removal of accessory marrow cells by soy bean agglutinin (SBA) ablated the inhibition of marrow CFU-E colonies by rTNF. Inhibition of colony growth was then restored by adding back SBA+ cells, but not by adding T lymphocytes or adherent cells. Conditioned medium prepared from bone marrow mononuclear cells stimulated by rTNF inhibited the growth of colonies from highly purified BFU-E derived CFU-E resistant to direct inhibition by rTNF. These findings indicate that rTNF does not directly inhibit CFU-E, but requires accessory cells to decrease erythropoiesis. These accessory cells reside in the SBA+ cell fraction, but are neither T cells nor adherent cells. Therefore, in order to produce anemia, TNF must induce release or production of a factor that directly inhibits erythroid colony growth.


Assuntos
Células da Medula Óssea , Eritropoese/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Ensaio de Unidades Formadoras de Colônias , Humanos , Técnicas In Vitro , Proteínas Recombinantes
6.
J Clin Invest ; 52(2): 324-36, 1973 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-4119161

RESUMO

The marrow cells of a patient with pure red cell aplasia markedly increased their rate of heme synthesis when they were freed from the host environment and were incubated in vitro. When the red cell aplasia was treated with cyclophosphamide and prednisone, marrow cell incorporation of (59)Fe into heme in vitro increased several weeks before a reticulocytosis was apparent, and was the earliest effect noted. The plasma gammaG-globulins of this patient inhibited heme synthesis by normal marrow cells or the patient's own marrow cells obtained after remission of the disease. Since the inhibition of heme synthesis could be the result of damage to erythroblasts, the patient's posttreatment marrow cells or normal marrow cells were labeled with (59)Fe and were then incubated with the patient's pretreatment, treatment, and posttreatment gammaG-globulins as well as normal gammaG-globulins. At the end of this incubation the supernatant and cells were separated and counted. Heme was extracted and also was counted. Treatment of the cells with the patient's pretreatment gammaG-globulins resulted in a release of 40% of the radioactive heme from the cells. This represented the loss of radioactive hemoglobin and was an index of erythroblast cytotoxicity. A progressive disappearance of the cytotoxic factor in the gammaG-globulins occurred in the 3 wk period preceding the onset of reticulocytes in the patient's blood. Posttreatment and normal gammaG-globulins did not produce this effect and increased injury of red cells and lymphocytes was not produced by the patient's pretreatment gammaG-globulins. These studies demonstrate a method for measuring erythroblast cytoxicity and show that red cell aplasia is associated with gammaG-globulins that specifically damage erythroblasts. Whether interference with new erythroblast development also occurs and contributes to the inhibition of heme synthesis has not yet been ascertained.


Assuntos
Anemia Aplástica/metabolismo , Eritrócitos Anormais/metabolismo , gama-Globulinas/fisiologia , Anemia Aplástica/tratamento farmacológico , Medula Óssea/metabolismo , Células da Medula Óssea , Ciclofosfamida/uso terapêutico , Eritropoetina/farmacologia , Heme/análise , Heme/biossíntese , Hemoglobinas/análise , Humanos , Isótopos de Ferro , Masculino , Pessoa de Meia-Idade , Prednisona/uso terapêutico , gama-Globulinas/análise
7.
J Clin Invest ; 94(1): 34-43, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7518834

RESUMO

Erythropoietin (EP), insulin-like growth factor I (IGF-I) and stem cell factor (SCF) each reduce apoptosis of human erythroid progenitor cells. To determine if these growth factors have additional roles in stimulating erythropoiesis, the proliferation, maturation, and survival of highly purified human erythroid colony-forming cells (ECFCs) were studied during the application of different combinations of these growth factors in a serum-free liquid culture. EP maintained cell viability and supported heme synthesis during erythroid maturation, with little increase in viable cell number or stimulation of DNA synthesis. The addition of SCF with EP resulted in a substantial increase in DNA synthesis, which was greater than that seen with the addition of EP and was associated with a large expansion in the number of ECFCs. Thus EP, by itself, produces little increase in cell proliferation, and expansion of the number of erythroid cells depends upon the presence of SCF with EP. The addition of IGF-I with EP led to enhanced heme synthesis and moderate cellular proliferation, but also greatly enhanced nuclear condensation and enucleation in the late erythroblasts. Thus EP, by itself, is not sufficient for complete end-terminal nuclear condensation/enucleation and the presence of IGF-I is necessary for this complete process. While EP greatly reduced apoptosis during 16 h of incubation at 37 degrees C, the addition of SCF and IGF-I with EP had little additional effect, but these additions enhanced DNA synthesis > 3.4-fold. Thus SCF may have an additional role in directly stimulating proliferation through a process that is distinct from apoptosis. Our observations indicate that EP prevents apoptosis and maintains erythroid cell viability and development. IGF-I enhances erythroid maturation and proliferation, but the proliferation of erythroid progenitors is mainly controlled by the addition of SCF with EP, independent of an effect on apoptosis.


Assuntos
Células Precursoras Eritroides/efeitos dos fármacos , Eritropoetina/farmacologia , Fatores de Crescimento de Células Hematopoéticas/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Apoptose/efeitos dos fármacos , Células Cultivadas , DNA/biossíntese , Células Precursoras Eritroides/fisiologia , Heme/biossíntese , Humanos , Proteínas Recombinantes/farmacologia , Fator de Células-Tronco
8.
J Clin Invest ; 84(4): 1340-4, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2551927

RESUMO

The role of erythropoietin (EP) in polycythemia vera (PV) is controversial, with some experiments suggesting that erythroid progenitors in PV are exquisitely sensitive to EP and EP dependent, and others suggesting that PV progenitors are EP independent. We have examined the characteristics of the EP receptor (EP-R) on erythroid colony-forming cells (ECFC) from patients with PV. In contrast to normal ECFC, which have two classes of EP-R, with 20% showing high affinity (Kd = 0.13 nM; range, 0.04-0.20 nM) and the remainder lower affinity (Kd = 0.37 nM; range, 0.28-0.57 nM), PV ECFC show a single class of 851 low affinity EP-R with Kd = 0.72 nM (range, 0.36-0.85 nM). ECFC from patients with secondary (EP driven) polycythemia or anemia show two classes of EP-R (Kd = 0.18 and 1.10 nM, respectively). Attempts to remove tightly bound EP from putative high affinity EP-R in PV did not reveal any higher affinity receptors. Determination of molecular size by crosslinking showed two proteins of 90 and 100 kD similar to those seen with normal EP-R. These studies indicate the PV ECFC have EP-R that are structurally similar to normal EP-R but lack the higher binding affinity for EP.


Assuntos
Eritropoetina/metabolismo , Policitemia Vera/metabolismo , Receptores de Superfície Celular/metabolismo , Reagentes de Ligações Cruzadas , Eletroforese em Gel de Poliacrilamida , Células Precursoras Eritroides/metabolismo , Eritropoese , Humanos , Receptores da Eritropoetina
9.
J Clin Invest ; 87(2): 391-6, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1991825

RESUMO

Because polycythemia vera (PV) is a clonal hematopoietic stem cell disease with a trilineage hyperplasia, and interleukin-3 (IL-3) stimulates trilineage hematopoiesis, we have studied the response of highly purified PV blood burst-forming units-erythroid (BFU-E) to recombinant human IL-3 (rIL-3). Whereas the growth of normal blood BFU-E in vitro rapidly declined by 40 and 60% after 24 and 48 h of incubation without 50 U/ml of rIL-3, the growth of PV BFU-E declined by only 10 and 30% under the same conditions, demonstrating a reduced dependence on rIL-3. A reduced dependence of PV BFU-E on recombinant human erythropoietin (rEP) was also present. Dose-response experiments showed a 117-fold increase in PV BFU-E sensitivity to rIL-3, and a 6.5-fold increase in sensitivity to rEP, compared to normal BFU-E, whereas blood BFU-E from patients with secondary polycythemia responded like normal BFU-E. Endogenous erythroid colony (EEC) formation, which is independent of the addition of rEP, was reduced by 50% after erythroid colony-forming cells were generated from PV BFU-E in vitro without rIL-3 for 3 d, whereas rEP-stimulated erythroid colonies were unaffected. These studies demonstrate a striking hypersensitivity of PV blood BFU-E to rIL-3, which may be the major factor in the pathogenesis of increased erythropoiesis without increased EP concentrations.


Assuntos
Células Precursoras Eritroides/efeitos dos fármacos , Interleucina-3/farmacologia , Policitemia Vera/sangue , Relação Dose-Resposta a Droga , Eritropoetina/farmacologia , Humanos , Técnicas In Vitro , Proteínas Recombinantes/farmacologia
10.
J Clin Invest ; 80(2): 357-66, 1987 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3038955

RESUMO

Morphological and biochemical studies of human colony-forming units-erythroid (CFU-E) have been hindered by their extreme rarity. Since burst-forming units-erythroid (BFU-E) develop into CFU-E, we used normal human blood BFU-E to generate large numbers of highly purified CFU-E in vitro. Using density centrifugation, sheep erythrocyte rosetting, surface immunoglobulin-positive cell depletion, adherence to plastic, and negative panning with monoclonal antibodies, human blood BFU-E were purified from 0.017 to 0.368%, a 22-fold purification with a 43% yield. The panned cells were cultured in methylcellulose with recombinant erythropoietin (rEp) and conditioned medium for 9 d. These cells were then collected and CFU-E were further purified using adherence and density centrifugation. This yielded almost 10(7) erythroid colony forming cells with a purity of 70 +/- 18%. Analysis of these cells by light and electron microscopy showed 94% erythroid cells. The prominent cell was a primitive blast with high nuclear/cytoplasmic ratio, dispersed nuclear chromatin and a distinct large nucleolus. The relation between the number of erythroid colonies and the number of day 9 cells plated in plasma clots was a straight line through the origin with a maximum number of erythroid colonies at 1 U/ml of rEp and no erythroid colonies without rEp. Specific binding with 125I-rEp showed that 60% of the binding was inhibited by excess pure erythropoietin (Ep), but not by albumin, fetal calf serum, and a variety of growth factors or glycoproteins. By days 12-13 of cell culture, when the progenitor cells matured to late erythroblasts, specific binding markedly declined. In this study, human CFU-E have been isolated in sufficient purity to characterize the morphology of these rare cells and in sufficient numbers to measure specific binding of Ep.


Assuntos
Eritroblastos/citologia , Eritropoese , Eritropoetina/metabolismo , Anticorpos Monoclonais , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Eritroblastos/metabolismo , Humanos , Técnicas In Vitro , Metilcelulose , Microscopia Eletrônica , Receptores de Superfície Celular/metabolismo , Receptores da Eritropoetina , Fatores de Tempo
11.
J Clin Invest ; 83(5): 1701-9, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2651478

RESUMO

The presence of heterogeneous erythroid progenitor cells, contaminant cells, or serum may alter erythroid colony development in vitro. To obtain highly purified colony-forming units-erythroid (CFU-E), we cultured partially purified human blood burst-forming units-erythroid (BFU-E) in methylcellulose with recombinant human erythropoietin (rHuEPO) for 7 d and generated cells that consisted of 30-60% CFU-E, but no BFU-E. A serum-free medium was used that allowed development of the same number of erythroid colonies as serum containing medium, but with a greater percentage of larger colonies. This medium consisted of delipidated crystalline bovine serum albumin, iron saturated transferrin, lipid suspension, fibrinogen, thrombin, Iscove's modified Dulbecco's medium/F-12[HAM], and insulin plus rHuEPO. When CFU-E were cultured in a limiting dilution assay and the percentage of nonresponder wells was plotted against cell concentration, both serum-free cultures and serum-containing cultures yielded overlapping straight lines through the origin indicating that CFU-E development did not depend on accessory cells and that insulin acted directly on the CFU-E. Human recombinant interleukin 3 (IL-3) and/or granulocyte-macrophage colony-stimulating factor had no effect on CFU-E growth, while they markedly enhanced BFU-E growth. Physiological concentrations of recombinant human insulin-like growth factor I (IGF-I) enhanced CFU-E growth in the absence of insulin and, together with rHuEPO in serum-free medium, provided a plating efficiency equal to that of serum-containing medium. Limiting dilution analysis in serum-free medium with IGF-I showed a straight line through the origin indicating that IGF-I also acted directly on the CFU-E and not through an effect on accessory cells. These data demonstrate that CFU-E do not require accessory cells, but do require IGF-I and/or insulin which act directly on the CFU-E.


Assuntos
Eritrócitos/fisiologia , Eritropoese/efeitos dos fármacos , Células-Tronco Hematopoéticas/fisiologia , Fator de Crescimento Insulin-Like I/fisiologia , Insulina/fisiologia , Somatomedinas/fisiologia , Adulto , Fenômenos Fisiológicos Sanguíneos , Divisão Celular , Ensaio de Unidades Formadoras de Colônias , Fatores Estimuladores de Colônias/farmacologia , Meios de Cultura , Contagem de Eritrócitos , Eritrócitos/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Substâncias de Crescimento/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Hormônios/farmacologia , Humanos , Interleucina-3/farmacologia
12.
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.

13.
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
14.
J Natl Cancer Inst ; 59(1): 107-11, 1977 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-875048

RESUMO

When spleen cells removed from plethoric BALB/c mice shortly after infection with Friend polycythemia virus were cultured, they subsequently increased their rate of hemoglobin synthesis in vitro without the addition of the hormone erythropoietin. The increased 59Fe incorporation into hemoglobin in vitro was part of a well-defined single wave unlike the progressive increase in hemoglobin synthesis that occurs in vivo. The peak occurred within the same total time (85-105 hr after infection), irrespective of either the virus dose or time after infection when the cells were removed from the animal and cultured. However, the magnitude of the peak increased with an increase in either of these two variables. Medium change experiments indicated that the time during which the peak occurred was not artificially determined by depletion of some medium component or the accumulation of an inhibitor. This system may be useful in separating the early events of Friend virus infection from the late effects on erythroid differentiation.


Assuntos
Eritropoese , Vírus da Leucemia Murina de Friend , Policitemia/fisiopatologia , Baço/fisiopatologia , Infecções Tumorais por Vírus/fisiopatologia , Animais , Divisão Celular , Transformação Celular Neoplásica , Meios de Cultura , Hemoglobinas/biossíntese , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos BALB C , Policitemia/etiologia , Policitemia/metabolismo , Baço/metabolismo , Fatores de Tempo
15.
Biochim Biophys Acta ; 1177(1): 15-24, 1993 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-8485165

RESUMO

The interaction of in vitro short-term glycated rat serum albumin with rat peritoneal cells (40% macrophages) was investigated. Using 125I-labeled albumins the following results were obtained. Glycated albumins showed a binding reaction at 4 degrees C, which appeared to reach equilibrium within 2 h. The concentration-dependent binding of glycated albumin showed saturation. Binding data evaluated for glycated albumin using the Sips equation are: average association constant Ko = 3.15 x 10(7) M-1 with a heterogeneity index of a = 0.8 and 1.12 x 10(4) binding sites per cell. Such binding sites were identified in 40% of the peritoneal cell preparations studied. Native albumins, maleylated albumin, chondroitinsulfates, polylysine, lysine, fructose, glucose and hexitol-lysine could not compete with radio-labeled glycated rat albumin for its binding site on peritoneal cells. Effective competitors were glycated human serum albumin, glycated polylysine and fructose-lysine. Although the contamination with minute amounts of advanced glycosylation end products (AGE) could not be excluded, short-term glycated albumin was found to be bound to membranes of peritoneal phagocytotic cells by fructose-lysine specific proteins, whose approximately defined molecular masses of 290 kDa are distinct from hitherto described binding proteins for AGE- and aldehyde-modified proteins or for the scavenger receptors.


Assuntos
Macrófagos/metabolismo , Albumina Sérica/metabolismo , Animais , Sítios de Ligação , Ligação Competitiva , Membrana Celular/metabolismo , Produtos Finais de Glicação Avançada , Humanos , Radioisótopos do Iodo , Cavidade Peritoneal , Ratos , Albumina Sérica/química , Albumina Sérica/farmacologia , Albumina Sérica Glicada
16.
Biochim Biophys Acta ; 1266(1): 57-63, 1995 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-7718622

RESUMO

Short-term exposure of human serum albumin to glucose in vitro results in the formation of fructosyllysine residues. Using short-term glucose-modified albumin the interactions with human monocytes and with the human monocyte-like cells U937, MonoMac 6, HL60, and THP1 were studied. Short-term glycated albumin was specifically bound by monocytes, U937 and MonoMac 6 cells, but not by HL60 and THP1 cells. This specific binding of short-term glycated albumin was inhibited by fructosyllysine, but not by hexitollysine. Short-term glycated albumin did not compete for binding of albumin, modified by advanced glycation end products. Scatchard analysis of the binding data indicated that there are 10,000 binding sites per cell in monocytes or U937 cells and 2000 sites per cell on MonoMac 6 cells with affinity constants of 9 x 10(6) M-1. Specific binding of short-term glycated albumin to human monocytes was observed in 29% of the 101 human subjects investigated. Ligand-receptor cross-linking and ligand blotting experiments revealed two binding proteins of 100 to 110 and 190 kDa in SDS-PAGE after membrane protein solubilization of U937 and MonoMac 6 cells. The binding of short-term glycated albumin to MonoMac 6 cells induced the production of the cytokines IL-1 and TNF.


Assuntos
Lisina/análogos & derivados , Monócitos/metabolismo , Receptores de Aminoácido/metabolismo , Sítios de Ligação , Ligação Competitiva , Linhagem Celular , Citocinas/biossíntese , Produtos Finais de Glicação Avançada , Humanos , Radioisótopos do Iodo , Lisina/metabolismo , Albumina Sérica/metabolismo , Albumina Sérica Glicada
17.
Biochim Biophys Acta ; 1266(1): 109-12, 1995 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-7718615

RESUMO

The ability of short-term in vitro glycated albumin to react with monocytes or the monocyte-like cells U937 is due to the Amadori adduct fructosyllysine. Two binding proteins of about 100 and 200 kDa have been previously described to interact specifically with the monocyte-like cell line U937. Detergent extracts from U937 cell membranes were used to purify the 100kDa protein by ion exchange chromatography, fructosyllysine-Sepharose affinity chromatography and SDS-PAGE. Six amino acids from the N-terminal end and two peptide sequences of 14 and 15 amino acids were identical with the N-terminus and the positions 349 to 362 and 610 to 624 of the major nuclear protein nucleolin. However, ligand blotting experiments with nuclear extracts from U937 and RIN cells showed no binding of glycated albumin with nucleolin. The reported amino acid sequences of the 100kDa fructosyllysine specific binding protein do not show any homologies with AGE-receptors. This receptor protein as a nucleolin-like polypeptide belongs to the superfamily of RNA-binding proteins.


Assuntos
Lisina/análogos & derivados , Monócitos/metabolismo , Proteínas Nucleares/isolamento & purificação , Proteínas de Ligação a RNA/isolamento & purificação , Sequência de Aminoácidos , Linhagem Celular , Membrana Celular/metabolismo , Lisina/metabolismo , Proteínas de Membrana/isolamento & purificação , Dados de Sequência Molecular , Proteínas Nucleares/química , Fosfoproteínas/química , Proteínas de Ligação a RNA/química , Nucleolina
18.
Arch Intern Med ; 139(10): 1151-3, 1979 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-314791

RESUMO

While taking orally administered anticoagulants, three patients had hemorrhages into their retropharyngeal and submandibular spaces, suffering eventual acute airway obstruction. One of the patients died. Despite the life-threatening nature of this complication of anticoagulant therapy, the diagnosis was obscure and initially veiled in complaints of sore throat or hoarseness, suggesting infection. Thorough investigation of such complaints is necessary in patients receiving anticoagulation therapy. If a hematoma is discovered, the patient should be admitted to the hospital for close observation and prompt reversal of anticoagulation with plasma. Intubation or tracheostomy also may be required.


Assuntos
Obstrução das Vias Respiratórias/induzido quimicamente , Anticoagulantes/efeitos adversos , Obstrução das Vias Respiratórias/diagnóstico , Obstrução das Vias Respiratórias/terapia , Hemorragia/induzido quimicamente , Hemorragia/diagnóstico , Hemorragia/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Soalho Bucal , Hemorragia Bucal/induzido quimicamente , Hemorragia Bucal/diagnóstico , Hemorragia Bucal/terapia , Doenças Faríngeas/induzido quimicamente , Doenças Faríngeas/diagnóstico , Doenças Faríngeas/terapia , Traqueotomia
19.
Arch Intern Med ; 147(6): 1179-80, 1987 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3036033

RESUMO

Pure red cell aplasia developed in a patient with small-cell lung cancer who was also taking sustained-release procainamide. Shortly after discontinuation of the procainamide preparation, a reticulocytosis and increasing hemoglobin level were observed.


Assuntos
Anemia Aplástica/induzido quimicamente , Procainamida/efeitos adversos , Idoso , Carcinoma de Células Pequenas/tratamento farmacológico , Preparações de Ação Retardada , Quimioterapia Combinada , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Infarto do Miocárdio/tratamento farmacológico , Procainamida/administração & dosagem
20.
Arch Intern Med ; 139(5): 584-6, 1979 May.
Artigo em Inglês | MEDLINE | ID: mdl-312628

RESUMO

Neutropenia associated with high-dose cimetidine therapy developed in a patient in whom earlier therapy, as well as rechallenge with low-dose cimetidine, did not result in neutropenia. As other factors cannot be implicated, a dose-related toxicity of cimetidine appears likely. Although the mechanism of cimetidine-induced neutropenia is unknown, it may involve the previously demonstrated ability of histamine H2 receptor antagonists to block the histamine-induced initiation of DNA synthesis in bone marrow stem cells.


Assuntos
Agranulocitose/induzido quimicamente , Cimetidina/efeitos adversos , Guanidinas/efeitos adversos , Neutropenia/induzido quimicamente , Adulto , Cimetidina/administração & dosagem , Cimetidina/uso terapêutico , Relação Dose-Resposta a Droga , Hemorragia Gastrointestinal/tratamento farmacológico , Humanos , Masculino
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