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2.
BJOG ; 117(12): 1553-7, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21126322

RESUMO

We evaluated the effect of so-called monitoring and treatment charts on the management of eclampsia in a referral hospital in Malawi. Baseline characteristics, clinical management, as well as overall maternal and perinatal outcome were compared by reviewing the medical files of two groups, before and after introduction of the charts in 2006. The use of the charts has resulted in improved monitoring of women with eclampsia and may have contributed to the reduction in the planned prelabour caesarean section rate from 87% to 33%, as more women underwent induction of labour after stabilisation (P = 0.020). Overall maternal and perinatal outcomes were similar.


Assuntos
Eclampsia/terapia , Hospitalização/economia , Adolescente , Adulto , Custos e Análise de Custo , Eclampsia/economia , Feminino , Fidelidade a Diretrizes , Humanos , Malaui , Prontuários Médicos , Guias de Prática Clínica como Assunto , Gravidez , Resultado da Gravidez , Prática Profissional/normas , Encaminhamento e Consulta/economia , Adulto Jovem
3.
Eur Respir J ; 31(2): 241-51, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18057054

RESUMO

The epidemiological association between cancer and exposure to ambient air pollution particles (particles with a 50% cut-off aerodynamic diameter of 10 microm (PM(10))) has been related to the ability of PM(10) and its constituent nanoparticles (NPs) to cause reactive oxidative species (ROS)-driven DNA damage. However, there are no data on the molecular response to these genotoxic effects. In order to assess whether PM(10), NP and ROS-driven DNA damage induce carcinogenesis pathways, A549 cells were treated with tert-butyl-hyperperoxide (Tbh), urban dust (UD), carbon black (CB), nanoparticulate CB (NPCB), benzo(a)pyrene (BaP) and NPCB coated with BaP for

Assuntos
Carcinógenos Ambientais/toxicidade , Transformação Celular Neoplásica/induzido quimicamente , Dano ao DNA/efeitos da radiação , Nanopartículas/toxicidade , Análise de Variância , Western Blotting , Linhagem Celular Tumoral , Ensaio Cometa , Quebras de DNA de Cadeia Dupla , Genes BRCA1 , Humanos , Técnicas In Vitro , Análise Multivariada , Mutagênicos/toxicidade , Estresse Oxidativo , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Sensibilidade e Especificidade
4.
J Physiol Pharmacol ; 58 Suppl 5(Pt 2): 437-44, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18204156

RESUMO

cAMP responsive element binding protein (CREB) plays an important role in transcriptional machinery. CREB signaling is altered in patients with asthma. However, the role of CREB in chronic obstructive pulmonary disease (COPD) is less clear. In the present study we assessed changes in subcellular CREB distribution and activation (CREB-P) in 35 stable COPD patients treated with formoterol (F), formoterol+budesonide (F/ICS), and formoterol+budesonide+theophylline (F/ICS/Th) b.i.d. for 4 weeks, using SDS-PAGE/WB in cytosol and nuclear extracts of induced sputum cells. The expression of CREB was increased after F/ICS in both cytosolic and nuclear fractions by about 40% and 24%, respectively (P<0.001, P<0.01), while CREB-P increased after F/ICS by about 50% (P<0.01) in both compartments. These changes were not affected by theophylline. In F/ICS-treated patients, relative accumulation of CREB in cytosol was observed. These findings indicate, that poor response to ICS therapy may be related to increased CREB-associated signaling.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/biossíntese , Citoplasma/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Albuterol/uso terapêutico , Western Blotting , Broncodilatadores/uso terapêutico , Núcleo Celular/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Humanos , Fosforilação , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/genética , Serina/metabolismo , Espirometria , Escarro/química , Escarro/metabolismo , Frações Subcelulares/metabolismo , Fatores de Transcrição
5.
J Physiol Pharmacol ; 58 Suppl 5(Pt 2): 461-70, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18204159

RESUMO

To assess whether nanoparticle (NP) driven DNA damage induces the expression of proinflammatory transcription factors such as NFB and AP-1 A549, lung epithelial cells were treated with Carbon Black (CB), nanoparticulate CB (NPCB), NPCB coated with BaP (BaP-NPCB) for various times ranging from 30 min to 24 h. DNA strand break was determined by the comet assay and cell cycle status was analyzed using flow cytometry. Nuclear extracts were used for WB analysis of P approximately Ser15-p53. EMSA was used to detect DNA binding. Tested NP caused single strand breaks and significantly altered cell cycle kinetics. NF-kappaB and AP-1 DNA binding were increased at early time points (2.3 and 2.6 fold at 1 hour, respectively). Effects were also found on Ser15-p53 phosphorylation. N-acetylcysteine blocked NP driven effects. In conclusion, NPCB and BaP-NPCB induce DNA damage, activating p53, proteins related to DNA repair and proinflammatory transcription factors.


Assuntos
Dano ao DNA/fisiologia , Células Epiteliais/metabolismo , Pulmão/metabolismo , NF-kappa B/metabolismo , Nanopartículas/toxicidade , Fuligem/toxicidade , Fator de Transcrição AP-1/metabolismo , Acetilcisteína/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/ultraestrutura , Sobrevivência Celular/efeitos dos fármacos , DNA/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Células Epiteliais/efeitos dos fármacos , Humanos , L-Lactato Desidrogenase/metabolismo , Pulmão/citologia , Pulmão/efeitos dos fármacos , Fosforilação , Suspensões , Proteína Supressora de Tumor p53/metabolismo
6.
Thorax ; 60(4): 293-300, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15790984

RESUMO

BACKGROUND: A study was undertaken to assess both oxidative stress and inflammation in the lungs of patients with chronic obstructive pulmonary disease (COPD) during severe and very severe exacerbations compared with those with stable COPD, healthy smokers, and non-smokers. Two sites within the lungs were compared: the large airways (in sputum) and the peripheral airways (by bronchoalveolar lavage (BAL)). METHODS: BAL fluid cell numbers and levels of tumour necrosis factor (TNFalpha) and interleukin (IL)-8 were measured as markers of airway inflammation and glutathione (GSH) levels as a marker of antioxidant status. Nuclear translocation of the pro-inflammatory transcription factors nuclear factor-kappaB (NF-kappaB) and activator protein 1 (AP-1) were also measured by electromobility shift assay in BAL fluid leucocytes and lung biopsy samples. RESULTS: Influx of inflammatory cells into the peripheral airways during exacerbations of COPD was confirmed. Increased IL-8 levels were detected in BAL fluid from patients with stable COPD compared with non-smokers and healthy smokers, with no further increase during exacerbations. In contrast, IL-8 levels in the large airways increased during exacerbations. GSH levels were increased in the BAL fluid of smokers (444%) and patients with stable COPD (235%) compared with non-smokers and were reduced during exacerbations (severe 89.2%; very severe 52.3% compared with stable COPD). NF-kappaB DNA binding in BAL leucocytes was decreased in healthy smokers compared with non-smokers (41.3%, n = 9, p<0.001) but did not differ in COPD patients, whereas AP-1 DNA binding was significantly decreased during exacerbations of COPD. CONCLUSION: There is evidence of increased oxidative stress in the airways of patients with COPD that is increased further in severe and very severe exacerbations of the disease. This is associated with increased neutrophil influx and IL-8 levels during exacerbations.


Assuntos
Bronquite/patologia , Estresse Oxidativo/fisiologia , Doença Pulmonar Obstrutiva Crônica/patologia , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Ensaio de Desvio de Mobilidade Eletroforética , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Interleucina-8/análise , Masculino , Pessoa de Meia-Idade , NF-kappa B/análise , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fator de Necrose Tumoral alfa/análise
7.
Am J Physiol Lung Cell Mol Physiol ; 282(2): L237-48, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11792628

RESUMO

There is now considerable evidence for an association between the levels of particulate air pollution [particulate matter <10 microm in aerodynamic diameter (PM(10))] and various adverse health endpoints. The release of proinflammatory mediators from PM(10)-exposed macrophages may be important in stimulating cytokine release from lung epithelial cells, thus amplifying the inflammatory response. A549 cells were treated with conditioned media from monocyte-derived macrophages stimulated with PM(10), titanium dioxide (TiO(2)), or ultrafine TiO(2). We demonstrate that only conditioned media from PM(10)-stimulated macrophages significantly increased nuclear factor-kappaB and activator protein-1 DNA binding, enhanced interleukin-8 (IL-8) mRNA levels as assessed by RT-PCR, and augmented IL-8 protein levels, over untreated controls. Furthermore, PM(10)-conditioned media also caused transactivation of IL-8 as determined by an IL-8-chloramphenicol acetyl transferase reporter. Analysis of these conditioned media revealed marked increases in tumor necrosis factor-alpha (TNF-alpha) and protein levels and enhanced chemotactic activity for neutrophils. Preincubation of conditioned media with TNF-alpha-neutralizing antibodies significantly reduced IL-8 production. These data suggest that PM(10)-activated macrophages may amplify the inflammatory response by enhancing IL-8 release from lung epithelial cells, in part, via elaboration of TNF-alpha.


Assuntos
Poluentes Atmosféricos/farmacologia , Células Epiteliais/imunologia , Macrófagos Alveolares/imunologia , Alvéolos Pulmonares/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Anticorpos/farmacologia , Linhagem Celular , Quimiotaxia de Leucócito/efeitos dos fármacos , Quimiotaxia de Leucócito/imunologia , Meios de Cultivo Condicionados/farmacologia , Proteínas de Ligação a DNA/metabolismo , Células Epiteliais/citologia , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/imunologia , Humanos , Interleucina-1/metabolismo , Interleucina-8/genética , Macrófagos Alveolares/efeitos dos fármacos , NF-kappa B/metabolismo , Neutrófilos/citologia , Tamanho da Partícula , Regiões Promotoras Genéticas/fisiologia , Alvéolos Pulmonares/citologia , RNA Mensageiro/análise , Fator de Transcrição AP-1/metabolismo , Fator de Necrose Tumoral alfa/imunologia
8.
Toxicol Appl Pharmacol ; 166(2): 101-10, 2000 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-10896851

RESUMO

Exposure to particulate air pollution (PM(10)) is associated with exacerbations of respiratory diseases and increased cardiopulmonary mortality. PM(10) induces lung inflammation in rats, which has been attributed to many factors, including the ultrafine components of PM(10), endotoxins, and transition metals. In this study, we investigated in alveolar epithelial (A549) cells whether PM(10) could activate nuclear factor-kappa B (NF-kappaB), a transcription factor stimulated in response to many proinflammatory agents. Our results show that PM(10) samples from various sites within the United Kingdom cause nuclear translocation, DNA-binding, and transcriptional activation of NF-kappaB in A549 cells. Furthermore, increased NF-kappaB activity was observed in the absence of IkappaB degradation. To evaluate the role of iron, A549 cells were exposed to PM(10) previously treated with phosphate-buffered saline (PBS), deferoxamine mesylate, or deferoxamine plus ferrozine. PBS-treated and, to a lesser extent, deferoxamine-treated PM(10) were able to activate NF-kappaB, whereas this response was completely abrogated in cells exposed to PM(10) treated with both deferoxamine and ferrozine. Moreover, we studied the effects of soluble components of PM(10) on NF-kappaB activation by exposing alveolar epithelial cells to soluble fractions from PM(10) treated with PBS or the metal chelators. We found that, compared with fractions from PBS-treated PM(10) which activated NF-kappaB, fractions from PM(10) treated with deferoxamine and ferrozine did not stimulate NF-kappaB activity above background levels. Coincubation of polymixin B, an endotoxin-binding compound, and PM(10) did not inhibit NF-kappaB. In summary, PM(10) activates NF-kappaB in A549 cells by an iron-mediated mechanism in the absence of IkappaB degradation.


Assuntos
Poluentes Atmosféricos/farmacologia , Proteínas I-kappa B/metabolismo , Ferro/fisiologia , NF-kappa B/metabolismo , Alvéolos Pulmonares/metabolismo , Adenocarcinoma/metabolismo , Núcleo Celular/metabolismo , DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Desferroxamina/farmacologia , Interações Medicamentosas , Ferrozina/farmacologia , Humanos , Neoplasias Pulmonares/metabolismo , NF-kappa B/genética , Tamanho da Partícula , Polimixina B/farmacologia , Alvéolos Pulmonares/citologia , Alvéolos Pulmonares/efeitos dos fármacos , Células Tumorais Cultivadas
9.
Am J Respir Crit Care Med ; 159(6): 1696-702, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10351906

RESUMO

It has been proposed that abnormal mechanical properties may contribute to capillary retention of polymorphonuclear leukocytes (PMN) in sepsis, leading to the development of organ dysfunction. The present study was designed to determine whether PMN rigidity is increased in severe sepsis, and whether changes in the rheologic behavior of PMN correlate with the clinical course in sepsis. Eighteen adults with severe sepsis were studied over a period of 14 d; 11 survived and seven died. PMN deformation behavior was investigated via micropore filtration, using the cell transit analyzer. On Day 0, PMN rigidity was 2.5-fold greater for sepsis patients than for five normal controls (p < 0.001). PMN rigidity progressively improved over the 14 d study period for patients who recovered, but not for those who died; clinical indicators correlated with PMN rigidity. Patient PMN also exhibited a 5-fold greater increase in rigidity in response to formyl-methionylleucylphenylalanine (fMLP) than did control PMN. Both the increased rigidity and enhanced response to fMLP could be simulated in vitro by incubation of normal PMN with tumor necrosis factor-alpha (TNF-alpha). We conclude that circulating PMN are more rigid in severe sepsis, and are "primed" for an augmented response to chemotactic stimuli. These findings support the hypothesis that cytokine-mediated increases of PMN rigidity may lead to sequestration of these cells in capillaries and to the consequent impairment of microvascular perfusion in sepsis.


Assuntos
Infecções/fisiopatologia , Neutrófilos/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Elasticidade , Feminino , Humanos , Infecções/patologia , Masculino , Pessoa de Meia-Idade , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia
10.
FEBS Lett ; 443(2): 235-9, 1999 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-9989612

RESUMO

Apocynin (4-hydroxy-3-methoxy-acetophenone) is a potent intracellular inhibitor of superoxide anion production in neutrophils. In this study, we studied the effect of apocynin on the regulation of the antioxidant glutathione (GSH) and activation of the transcription factor AP-I in human alveolar epithelial cells (A549). Apocynin enhanced intracellular GSH by increasing gamma-glutamylcysteine synthetase activity in A549 cells. Apocynin also increased the expression of gamma-GCS heavy subunit mRNA. This was associated with increased AP-1 DNA binding as measured by the electrophoretic mobility shift assay. These data indicate that apocynin displays antioxidant properties, in part, by increasing glutathione synthesis through activation of AP-1.


Assuntos
Acetofenonas/farmacologia , Antioxidantes/farmacologia , Glutationa/biossíntese , Alvéolos Pulmonares/efeitos dos fármacos , Fator de Transcrição AP-1/metabolismo , Sequência de Bases , Linhagem Celular , DNA/metabolismo , Primers do DNA , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Humanos , Ligação Proteica , Alvéolos Pulmonares/enzimologia , Alvéolos Pulmonares/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
11.
Scand J Rehabil Med ; 30(2): 87-94, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9606770

RESUMO

The purpose of this study was to review the literature on the effects of day-hospital rehabilitation (DHR) in stroke patients. In The Netherlands DHR concerns a multidisciplinary approach to decrease disability and handicap and to optimize quality of life in an outpatient setting. Data were collected by a computer-aided search of published randomized trials. Fifteen articles reporting on seven randomized controlled trials were selected. Data extraction included a score for quality of the methods, based on four categories: "study population", "interventions", "effects" and "data presentation and analysis". To each criterion a weight was attached and the maximum score was set at 100 points. In judging the methodological quality of the selected studies, one study proved insufficient. Of the remaining studies the sum score varied from 34 to 67, with a mean of 50. Comparison of the results of the studies is complicated by different definitions of DHR, different natures of the control group and the study population, and the variety of measurement instruments applied. Often instruments were applied whose reliability and validity was not proven. As of now it is not possible to prove that DHR for stroke patients is effective. In future research a standardized definition of DHR, a uniform control group, and acceptable research methodology and adequate measurement instruments must be applied.


Assuntos
Transtornos Cerebrovasculares/reabilitação , Idoso , Instituições de Assistência Ambulatorial , Humanos , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Eur J Immunol ; 28(1): 80-9, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9485188

RESUMO

Appropriate recruitment of neutrophils to sites of infection or tissue injury is a key event in the inflammatory response. A number of studies have shown the critical role of selectins in tethering and rolling of neutrophils on vascular endothelium, as well as a more complex regulatory role, since they have the potential to alter leukocyte recruitment by triggering beta2 integrin-mediated adhesion. In this study, we report that in contrast to patients "at risk" of developing acute respiratory disease syndrome (ARDS), elevated plasma levels of soluble E-selectin are found in patients with established disease. Since neutrophil granulocytes are implicated in ARDS pathogenesis, we have investigated the possibility of a link between elevated soluble plasma E-selectin levels and disease progression by examining the effects of soluble recombinant E-selectin (E-zz) upon neutrophil function. In this paper, we describe the novel finding that exposure of neutrophils to E-zz potentiates a number of neutrophil functions which may act to drive inflammatory processes. Although neutrophil deformability, an important parameter determining retention within the lung microvasculature, was not affected by E-zz, neutrophil polarization was observed. In addition, neutrophil beta2 integrin-mediated adhesion was found to be augmented by E-zz without alteration in levels of surface expression of alphaMbeta2 or the "activation" reporter epitope defined by monoclonal antibody 24. Concomitantly with increased beta2 integrin-mediated adhesion, we observed an inhibition of formyl-Met-Leu-Phe-directed chemotaxis. Together with an augmentation of neutrophil reactive oxidant species production and release of superoxide anions, these data raise the possibility that soluble E-selectin exerts pro-inflammatory effects upon neutrophil function at sites of inflammation, thereby exacerbating disease processes.


Assuntos
Selectina E/farmacologia , Neutrófilos/efeitos dos fármacos , Síndrome do Desconforto Respiratório/patologia , Antígenos CD18/fisiologia , Adesão Celular , Fatores Quimiotáticos/farmacologia , Quimiotaxia de Leucócito/efeitos dos fármacos , Progressão da Doença , Endotélio Vascular/citologia , Humanos , Perfuração Intestinal/complicações , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/farmacologia , Explosão Respiratória , Síndrome do Desconforto Respiratório/sangue , Síndrome do Desconforto Respiratório/etiologia , Risco , Solubilidade , Superóxidos/metabolismo
13.
Mediators Inflamm ; 5(3): 188-90, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-18475714

RESUMO

Lipocortn 1 (Lc1) is an anti-inflammatory protein, which, given systemically, inhibits polymorphonuclear neutrophil (PMN) emigration from the circulation to sites of inflammation; delivery of Lc1 to the inflamed site is ineffective. We have examined the effect of Lc1 on changes in PMN deformability, and observed a consistent improvement in the deformability of unstimulated PMN; N-formyl-methionyl-leucyl-phenylalanine (fMLP)-activated cell deformability was unaltered. A Lc1-induced increase in cell deformability may reduce PMN sequestration so contributing to the anti-migratory effects of systemic Lc1 previously demonstrated in vivo.

14.
Am J Respir Cell Mol Biol ; 13(5): 531-9, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7576688

RESUMO

Neutrophil (PMN) sequestration in the pulmonary microvasculature precedes the migration of these cells into the airspaces in inflamed lungs. Intratracheal instillation of the heat-killed organism Corynebacterium parvum in the rat induces an alveolitis in which PMN constitute 70 to 80% of the total cell count in the bronchoalveolar lavage (BAL). This acute alveolitis results in increased sequestration in the pulmonary microvasculature of 51Cr-labeled PMN when compared with control lungs. The aims of this study were to confirm this increased pulmonary PMN sequestration using unlabeled cells and to assess the function and adhesion molecule expression of such sequestered PMN. We counted the number of PMN and erythrocytes obtained by pulmonary vascular lavage (PVL) and compared the ratio of these two cell types in PVL and peripheral blood (PB) as a measure of the sequestration of PMN in the pulmonary vasculature. Compared with control animals, PVL in C. parvum-treated rats had higher PMN counts, which could not be accounted for by the PB leukocytosis. Sequestration of PMN in the pulmonary microvasculature depends on several factors, including the upregulation of adhesion molecules on both PMN and endothelial surfaces and the ability of the cells to deform when passing through the microcirculation. Cells obtained from the PVL were less deformable than PB cells in control but not in C. parvum-treated animals. The expression of the CD18 integrin on PMN obtained from the PVL of C. parvum-treated animals was increased compared with cells from control animals.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Antígenos CD11/metabolismo , Antígenos CD18/metabolismo , Neutrófilos/imunologia , Pneumonia/patologia , Animais , Contagem de Leucócitos , Masculino , Neutrófilos/patologia , Pneumonia/imunologia , Propionibacterium acnes , Ratos , Superóxidos/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
15.
Thorax ; 50(6): 661-7, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7638810

RESUMO

BACKGROUND: The transit of neutrophils through the pulmonary microvasculature is prolonged compared with red blood cells and is increased further during cigarette smoking and in exacerbations of chronic obstructive pulmonary disease. The increased residence time (sequestration) of neutrophils in the pulmonary capillaries in these conditions may be the first step leading to the accumulation of cells within the lung interstitium and in the bronchoalveolar space, so potentiating lung damage. A rat model has been developed to investigate the factors which may influence neutrophil transit through the lung microvasculature. METHODS: Intratracheal instillation of the heat killed organism Corynebacterium parvum was used to induce an acute neutrophil alveolitis. Neutrophils and red blood cells were isolated from donor rats, labelled with two distinct radioisotopes, and then reinjected into recipient rats to assess their transit through the pulmonary circulation. To ascertain whether peripheral blood neutrophils were minimally altered by the isolation procedure their functional status in vitro was compared with that of inflammatory neutrophils in a number of assays commonly used as descriptors of neutrophil activation. The influence of neutrophil activation on the accumulation of cells in the lungs was assessed by comparing the lung sequestration of control neutrophils, isolated from peripheral blood, with that of inflammatory neutrophils obtained from bronchoalveolar lavage of inflamed rat lungs. Lung sequestration of neutrophils was defined as the fold increase in the ratio of neutrophils labelled with chromium-51 to red blood cells labelled with technetium-99m in lung tissue compared with the same ratio in peripheral blood. RESULTS: Sequestration of peripheral blood neutrophils occurred in control rat lungs as shown by a 17.5 (2.1) fold increase in the ratio of neutrophils to red blood cells in the pulmonary circulation compared with the ratio of these cells in the peripheral circulation. When inflammatory neutrophils, obtained by bronchoalveolar lavage from C parvum-treated animals, were injected into control rats, the increase was 90.6 (11.0) fold. Induction of an inflammatory response in the lung tissue of the recipient rat also caused an increase in the sequestration of control neutrophils compared with the same cells in control rat lungs which was, however, less marked than when inflammatory neutrophils were used (34.7 (4.7) fold). The mean (SE) pressure developed on filtration of inflammatory neutrophils in vitro through a millipore filter (7.53 (0.2) cm H2O) was greater than that of peripheral blood neutrophils (1.18 (0.2) cm H2O). Increased filtration pressure indicates a decrease in cell deformability and suggests that this may be a contributory factor to the increased sequestration of inflammatory neutrophils in the pulmonary vasculature. CONCLUSIONS: This study shows that there is sequestration of neutrophils in the pulmonary vasculature in normal rat lungs which increases in acute lung inflammation and when inflammatory neutrophils are injected into control animals. In this model changes in the neutrophil, such as cell deformability, may have a more important role in inducing increased neutrophil sequestration than the inflammatory response in the lungs.


Assuntos
Pulmão/irrigação sanguínea , Neutrófilos/fisiologia , Pneumonia/patologia , Animais , Antígenos de Bactérias , Líquido da Lavagem Broncoalveolar/citologia , Movimento Celular/fisiologia , Células Cultivadas , Radioisótopos de Cromo , Modelos Animais de Doenças , Eritrócitos/diagnóstico por imagem , Masculino , Microcirculação , Ativação de Neutrófilo/fisiologia , Neutrófilos/diagnóstico por imagem , Pneumonia/diagnóstico por imagem , Pneumonia/etiologia , Propionibacterium acnes/imunologia , Cintilografia , Ratos , Fluxo Sanguíneo Regional , Tecnécio
16.
J Appl Physiol (1985) ; 77(4): 1801-10, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7836203

RESUMO

The potential for neutrophils to obstruct microvessels was evaluated by measuring transit of individual neutrophils through 8-microns pores in an automated cell transit analyzer (CTA) or into micropipettes (4-8 microns ID). Stimulation in vitro by the chemotactic agent N-formyl-methionyl-leucyl-phenylalanine. (fMLP), cigarette smoke, or purified antineutrophil cytoplasm antibodies greatly increased flow resistance, but the response varied in its dependence on time and pore diameter. Cigarette smoke or fMLP caused rapid loss of cellular deformability, although observations were complicated by changes in cell shape: progressive bipolar shape formation (after treatment with fMLP) could facilitate entry into larger pores (approximately 8 microns), whereas blebs induced by cigarette smoke caused bridging of these pores with cell immobilization. These processes led to an underestimation of the changes in deformability by the CTA. Neutrophils responded slowly to the antineutrophil cytoplasm antibodies (approximately 30 min), with a greater increase in flow resistance evaluated by a micro-pipette (4-6 microns ID) than by the CTA. We conclude that the effect of neutrophil stimulation on flow through capillary-sized vessels is potentially great (with resistance typically increased 10-fold or even complete blockage) but may depend on the vascular and cellular geometry and may be local or disseminated, depending on the rate of the rheological response.


Assuntos
Autoanticorpos/farmacologia , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Ativação de Neutrófilo/fisiologia , Neutrófilos/fisiologia , Fumaça , Adulto , Anticorpos Anticitoplasma de Neutrófilos , Citocalasina B/farmacologia , Humanos , Imunoglobulina G/farmacologia , Contagem de Leucócitos , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Reologia
18.
Am J Respir Crit Care Med ; 149(6): 1526-33, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8004309

RESUMO

Neutrophils within the lungs are considered to play an important role in the pathogenesis of pulmonary emphysema. We have studied the intravascular distribution of reinjected autologous 111In-labeled neutrophils in lung specimens resected 10 min after reinjection from 10 patients undergoing surgery for peripheral bronchogenic tumors. An excess of neutrophils relative to that expected for the 99mTc-labeled erythrocyte blood volume was confirmed in all specimens (range, 3- to 136-fold). In seven specimens which were completely examined, this excess displayed a skewed distribution, with a median neutrophil sequestration of 20-fold excess, and correlated with local blood volume (r = -0.51; p < 0.001). There was also a significant correlation between alveolar wall surface area per unit volume of lung (AWUV) and neutrophil excess, when randomly selected tissue blocks from each specimen were analyzed (r = 0.34, n = 51, p = 0.012). This same trend was demonstrated when whole specimen median values were considered (r = 0.64, n = 7, p = 0.07). Thus in areas of the lungs with lower AWUV values (increasing microscopic emphysema), fewer neutrophils were present. These studies add further support to the view that emphysema per se is not associated with an increased sequestration of pulmonary intravascular neutrophils.


Assuntos
Volume Sanguíneo , Carcinoma Broncogênico/sangue , Carcinoma Broncogênico/diagnóstico , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/diagnóstico , Neutrófilos/patologia , Circulação Pulmonar , Enfisema Pulmonar/sangue , Enfisema Pulmonar/diagnóstico , Idoso , Análise de Variância , Carcinoma Broncogênico/complicações , Carcinoma Broncogênico/cirurgia , Feminino , Câmaras gama , Humanos , Radioisótopos de Índio , Contagem de Leucócitos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/fisiopatologia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Pneumonectomia , Alvéolos Pulmonares/patologia , Enfisema Pulmonar/complicações , Enfisema Pulmonar/fisiopatologia , Enfisema Pulmonar/cirurgia , Análise de Regressão
19.
Am Rev Respir Dis ; 148(5): 1277-83, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8239165

RESUMO

Acute cigarette smoking increases the sequestration of neutrophils in the lungs of humans. This may be due to the delayed transit of cells in the pulmonary microcirculation, which may result from a reduction in cell deformability as suggested by in vitro studies of smoke-exposed neutrophils. In order to support this hypothesis we wished to determine if a reduction in leukocyte deformability could be measured in whole blood exposed to smoke in vitro or in vivo. Whole blood filterability, which largely reflects leukocyte deformability, was measured as the pressure developed by filtration of diluted whole blood through a micropore membrane. Whole blood filtration pressures did not change when blood was exposed to smoke in vitro or in venous blood after acute smoking in vivo. However, arterial blood sampled from chronic smokers during acute smoking showed a consistent reduction in leukocyte deformability associated with a small increase in plasma elastase. To assess whether these changes were induced by oxidants in cigarette smoke, we measured the levels of the antioxidant glutathione (GSH), erythrocyte (RBC) membrane fragility, and products of lipid peroxidation in plasma and RBC in blood exposed to smoke in vivo and in vitro. No change in RBC lipid peroxidation or membrane fragility could be detected after in vitro smoke exposure, possibly because of the high antioxidant capacity of the RBC. However, reduced blood GSH levels and increased levels of lipid peroxidation products were detected in plasma, reflecting oxidant stress. In contrast, we were unable to detect evidence of an increased oxidant burden in blood after acute smoking in vivo, in either arterial or venous blood samples.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Leucócitos/fisiologia , Fumar/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Carboxihemoglobina/análise , Deformação Eritrocítica , Filtração , Glutationa/sangue , Humanos , Técnicas In Vitro , Elastase de Leucócito , Peroxidação de Lipídeos , Masculino , Pessoa de Meia-Idade , Elastase Pancreática/sangue
20.
Exp Lung Res ; 18(6): 813-27, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1468412

RESUMO

Peripheral blood neutrophils were harvested and exposed acutely in vitro to physiologically attainable levels of cigarette smoke. The adherence of radiolabeled neutrophils subsequently to alveolar epithelial cell monolayers was measured. In contrast to control cells, smoke-exposed neutrophils were significantly less adherent and failed to increase their adherence following stimulation with phorbol ester or f-met-leu-phe (fMLP). Flow cytometric analysis of the cell surface adhesion protein CD18 demonstrated no significant change in expression following in vitro smoke exposure and, furthermore, no increase in surface CD18 of smoke-exposed cells following consecutive fMLP stimulation was demonstrated. Acute in vivo cigarette smoking of up to 4 cigarettes also did not alter peripheral blood neutrophil CD18 expression. Cell spreading and chemokinesis, but not chemotaxis, was also impaired following in vitro smoke exposure. These data suggest that acute cigarette smoke may impair the crucial neutrophil functions of adherence and movement. However, the chronic effects of cigarette smoke exposure may clearly differ.


Assuntos
Neutrófilos/citologia , Fumar/efeitos adversos , Adulto , Anticorpos Monoclonais , Antígenos CD/análise , Antígenos de Superfície/análise , Adesão Celular/fisiologia , Linhagem Celular , Quimiotaxia de Leucócito/fisiologia , Células Epiteliais , Citometria de Fluxo , Humanos , Integrinas/análise , Teste de Inibição de Aderência Leucocítica , Neutrófilos/imunologia , Fatores de Tempo
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