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1.
Thromb Res ; 128(5): e100-6, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21862110

RESUMO

INTRODUCTION: Monocyte- and microparticle (MP)-associated tissue factor (TF) is upregulated in diabetes. Lipopolysaccharide (LPS) induces expression of TF and alternatively spliced TF (asTF) and increases MP release from monocytes. Using LPS-stimulated TF-bearing human monocytes, we examined whether glibenclamide, a sulfonylurea used to treat diabetes type 2, might possess anticoagulant properties. METHODS: We studied the effects of glibenclamide on cell- and supernatant-associated procoagulant activity (Factor Xa-generating assay and clot formation assay), on expression of TF and asTF (flow cytometry, RT-qPCR, western blot) and on cell viability and MP release (flow cytometry). RESULTS: Glibenclamide dose-dependently decreased procoagulant activity of cells and supernatants. The reduction in cellular procoagulant activity coincided with reduced expression of TF and asTF in cells, whereas cell viability remained almost unchanged. The glibenclamide-induced reduction in procoagulant activity of supernatants appeared to be associated with a decreased number of released MPs. CONCLUSIONS: Reduction of monocyte- and supernatant-associated procoagulant activity by glibenclamide is associated with decreased expression of TF and asTF and possibly with a reduced MP number. Our data indicate that glibenclamide reduces the prothrombotic state in LPS-stimulated monocytes in vitro. Glibenclamide might therefore also have an anticoagulant effect in vivo, but this needs to be further evaluated.


Assuntos
Anticoagulantes , Glibureto/farmacologia , Hipoglicemiantes/farmacologia , Monócitos/efeitos dos fármacos , Testes de Coagulação Sanguínea , Sobrevivência Celular/efeitos dos fármacos , Micropartículas Derivadas de Células/efeitos dos fármacos , Células Cultivadas , Humanos , Lipopolissacarídeos , Trombofilia/tratamento farmacológico , Tromboplastina/análise , Tromboplastina/efeitos dos fármacos
2.
Occup Environ Med ; 65(3): 211-4, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17855504

RESUMO

BACKGROUND: Workers producing bacterial single-cell protein (BSCP), "bioprotein," are exposed to organic dust containing high levels of endoxins (lipopolysaccharides, LPS). Workers in this industry have complained of episodes of fever, fatigue, chest tightness, skin dryness and rubor. The aim of the present study was to quantify LPS and inflammatory mediators in plasma among the workers and non-exposed control subjects. METHODS: We included eight non-smoking production workers, aged 32-51 (median 38), and eight non-smoking, non-exposed controls, aged 30-51 (median 39). Airborne and plasma endotoxin concentrations were measured, as well as plasma hsCRP and different cytokines, chemokines and metalloproteinases. RESULTS: The workers who did not use personal respiratory protection were exposed to varying airborne levels of endotoxin, 430 (75-15 000) EU/m3 (median, range). The level of plasma LPS was significantly elevated (p = 0.01) among the workers compared to the non-exposed controls. The workers also had elevated levels of MCP-1 (p = 0.02), MIP-1alpha (p = 0.05) and MMP-3 (p = 0.04). IL-6 and hsCRP were also elevated among the exposed group, but not significantly (p = 0.10 and p = 0.07, respectively). CONCLUSIONS: In this study, we detected LPS in plasma of individuals exposed to high levels of LPS at their workplace. This finding is supported by elevated levels of several inflammatory cytokines among the workers, significantly exceeding that of the non-exposed control group. To the best of our knowledge, this is the first time that plasma LPS, together with increased inflammatory markers in plasma, has been detected in an occupational setting.


Assuntos
Poluentes Ocupacionais do Ar/sangue , Bioquímica , Indústria Química , Lipopolissacarídeos/sangue , Adulto , Ração Animal , Fenômenos Bioquímicos , Biomarcadores/sangue , Proteína C-Reativa/análise , Estudos de Casos e Controles , Citocinas/sangue , Monitoramento Ambiental/métodos , Feminino , Humanos , Pneumopatias/etiologia , Masculino , Metaloproteases/sangue , Methylococcus capsulatus , Pessoa de Meia-Idade , Doenças Profissionais/etiologia , Exposição Ocupacional
3.
Thromb Res ; 119(5): 621-30, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-16844202

RESUMO

INTRODUCTION: Cell surface tissue factor (TF) is normally encrypted, but can be activated by various cellular perturbations. Exposure of TF bearing cells to calcium ionophore has been reported to increase TF activity, de-encrypt TF, by phosphatidylserine (PS)-dependent and -independent mechanisms. Our aim has been to examine at the single cell level, if increased cell surface PS coincided with increased cell surface TF antigen, and cell death (necrosis, 7-AAD-intercalation), and relate this to monocyte- and microparticle (MP)-associated procoagulant activity. MATERIALS AND METHODS: We exposed lipopolysaccharide-stimulated, human, elutriation-purified, cryopreserved TF bearing monocytes to increasing concentrations of calcium ionophore (A23187) and measured procoagulant activity in cells and supernatants. These measurements were compared with quantification of cell surface TF and PS (Annexin V) and of cell necrosis (7-AAD) by flow cytometry, and complemented by confocal microscopy. RESULTS: We observed that calcium ionophore increased cellular and MP-associated TF activity, but not cell surface TF antigen. The discrepancy between TF activity and TF antigen coincided with a dose-dependent increase in the number of cells expressing PS. These cells were to a large extent necrotic and many of them also expressed TF. CONCLUSIONS: We suggest such TF positive dying cells to contribute to the discordance between TF activity and TF expression. Calcium ionophore also increased MP-associated TF activity and release of MPs may be a way to disseminate procoagulant activity. Our findings emphasize the importance of adequately assessing cell death and taking into consideration its possible role in experiments with calcium ionophore.


Assuntos
Cálcio/metabolismo , Ionóforos/farmacologia , Monócitos/efeitos dos fármacos , Tromboplastina/efeitos dos fármacos , Coagulação Sanguínea/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Relação Dose-Resposta a Droga , Fator Xa/análise , Fator Xa/biossíntese , Citometria de Fluxo , Humanos , Monócitos/metabolismo , Tromboplastina/metabolismo
4.
Heart ; 91(3): 299-304, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15710705

RESUMO

OBJECTIVES: To test the hypothesis that heat shock protein (Hsp) 70 may be released into the circulation after acute myocardial infarction (AMI) by exploring the kinetics of Hsp70 release and the relations between Hsp70 and markers of inflammation and myocardial damage in AMI. DESIGN: Blood samples from 24 patients were prospectively collected through to the first day after AMI. Hsp70, interleukin (IL) 6, IL-8, and IL-10 in serum were measured by enzyme linked immunosorbent assay (ELISA). RESULTS: Median Hsp70 concentrations in AMI patients measured at arrival, six hours thereafter, and the following morning were 686, 868, and 607 pg/ml, respectively. These concentrations were all significantly different from those of the control patients with angina with a median serum Hsp70 concentration of 306 pg/ml. Peak Hsp70 correlated with creatine kinase (CK) MB (r = 0.62, p < 0.01) and cardiac troponin T (r = 0.58, p < 0.01). Furthermore, serum Hsp70 correlated with IL-6 and IL-8 at six hours (r = 0.60, p < 0.01 and r = 0.59, p < 0.01, respectively). CONCLUSIONS: In this study, Hsp70 was rapidly released into the circulation after AMI. Circulating Hsp70 is suggested as a marker of myocardial damage. In addition, Hsp70 may have a role in the inflammatory response after AMI.


Assuntos
Proteínas de Choque Térmico HSP70/sangue , Isquemia Miocárdica/sangue , Biomarcadores/sangue , Creatina Quinase/sangue , Feminino , Humanos , Interleucina-10/sangue , Interleucina-6/sangue , Interleucina-8/sangue , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/patologia , Isquemia Miocárdica/patologia , Miocárdio/patologia , Necrose , Estudos Prospectivos , Troponina/sangue
5.
Scand J Gastroenterol ; 38(8): 871-7, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12940442

RESUMO

BACKGROUND: The majority of hemochromatosis patients are homozygous for the HFE-C282Y mutation. However, less than half of C282Y homozygous subjects identified by population screening studies actually develop the disease. The cytokine TNF-alpha is implicated in the regulation of iron metabolism at different levels. Our aim was to study the role of TNF-alpha and its promoter polymorphisms in the phenotypic expression of hemochromatosis in individuals with and without the C282Y mutation. METHODS: We studied 4 groups of 10 subjects each: (1) C282Y homozygotes without clinical hemochromatosis; (2) C282Y homozygotes with hemochromatosis; (3) secondary hemochromatosis (without C282Y mutation); and (4) controls. Groups were age-matched and sex-matched. Peripheral blood mononuclear cells (PBMC) were stimulated with lipopolysaccharide (LPS) and the release of TNF-alpha was measured. Additionally, the G/A polymorphisms at position -238 and -308 of the TNF-alpha, gene were determined by PCR and RFLP analysis in 178 hemochromatosis patients and 41 controls. RESULTS: TNF-alpha production from PBMC at 8 and 24 h after increasing concentrations of LPS stimulation were similar in the four groups. The prevalence of TNF-alpha polymorphisms was similar in patients and controls. The prevalences of cirrhosis, siderosis, median s-ferritin and median ALT values were similar in patients with and without the TNF-alpha polymorphisms. CONCLUSIONS: Neither TNF-alpha, released from PBMC nor the presence of TNF-alpha polymorphisms seem to be associated with disease manifestation in hemochromatosis.


Assuntos
Expressão Gênica/genética , Hemocromatose/genética , Antígenos de Histocompatibilidade Classe I/genética , Proteínas de Membrana/genética , Polimorfismo Genético/genética , Regiões Promotoras Genéticas/genética , Fator de Necrose Tumoral alfa/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Proteína da Hemocromatose , Homozigoto , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Mutação/genética , Fenótipo
6.
J Thromb Haemost ; 1(5): 971-5, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12871363

RESUMO

In a randomized trial on the effect of dalteparin for 5 weeks after HRS we evaluated hemostatic variables in plasma sampled before and 1, 6 and 35 days postoperatively. In 218 patients we found that prothrombin fragment 1 + 2 (F1 + 2), thrombin-antithrombin complexes (TAT), d-dimer and fibrinogen were significantly higher on day 35 as compared with baseline values in the placebo group (P < 0.001 for all). The same pattern was found in the dalteparin group, but with significantly lower values for F1 + 2, TAT and d-dimer. In patients in the placebo group with venographically proven deep vein thrombosis (DVT) on day 35 (33%), significantly higher values were found for F1 + 2, TAT and d-dimer than in patients without DVT. Patients in the highest quartile of d-dimer (>2850 ng mL-1) had an odds ratio for the presence of DVT of 24.0 when compared with patients in the lowest quartile (<1625 ng mL-1). It is concluded that a substantial hypercoagulability is sustained until day 35 after HRS, significantly reduced with prolonged administration of dalteparin.


Assuntos
Artroplastia de Quadril/efeitos adversos , Trombofilia/tratamento farmacológico , Trombose/prevenção & controle , Idoso , Anticoagulantes/farmacologia , Anticoagulantes/uso terapêutico , Fatores de Coagulação Sanguínea/análise , Fatores de Coagulação Sanguínea/efeitos dos fármacos , Dalteparina/farmacologia , Dalteparina/uso terapêutico , Feminino , Humanos , Masculino , Flebografia , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/prevenção & controle , Trombofilia/etiologia , Trombofilia/prevenção & controle , Trombose/tratamento farmacológico , Trombose/etiologia , Trombose Venosa/diagnóstico , Trombose Venosa/prevenção & controle
7.
J Endotoxin Res ; 7(6): 401-20, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11753210

RESUMO

Neisseria meningitidis causes meningitis, fulminant septicemia or mild meningococcemia attacking mainly children and young adults. Lipopolysaccharides (LPS) consist of a symmetrical hexa-acyl lipid A and a short oligosaccharide chain and are classified in 11 immunotypes. Lipid A is the primary toxic component of N. meningitidis. LPS levels in plasma and cerebrospinal fluid as determined by Limulus amebocyte lysate (LAL) assay are quantitatively closely associated with inflammatory mediators, clinical symptoms, and outcome. Patients with persistent septic shock, multiple organ failure, and severe coagulopathy reveal extraordinarily high levels of LPS in plasma. The cytokine production is compartmentalized to either the circulation or to the subarachnoid space. Mortality related to shock increases from 0% to > 80% with a 10-fold increase of plasma LPS from 10 to 100 endotoxin units/ml. Hemorrhagic skin lesions and thrombosis are caused by up-regulation of tissue factor which induces coagulation, and by inhibition of fibrinolysis by plasminogen activator inhibitor 1 (PAI-1). Effective antibiotic treatment results in a rapid decline of plasma LPS (half-life 1-3 h) and cytokines, and reduced generation of thrombin, and PAI-1. Early antibiotic treatment is mandatory. Three intervention trials to block lipid A have not significantly reduced the mortality of meningococcal septicemia.


Assuntos
Lipopolissacarídeos , Infecções Meningocócicas , Neisseria meningitidis/patogenicidade , Citocinas/sangue , Fibrinólise/fisiologia , Humanos , Lipopolissacarídeos/sangue , Lipopolissacarídeos/química , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/toxicidade , Meningite Meningocócica/sangue , Meningite Meningocócica/diagnóstico , Meningite Meningocócica/tratamento farmacológico , Infecções Meningocócicas/sangue , Infecções Meningocócicas/diagnóstico , Infecções Meningocócicas/tratamento farmacológico , Penicilina G/uso terapêutico , Penicilinas/uso terapêutico , Inibidor 1 de Ativador de Plasminogênio/sangue , Inibidor 1 de Ativador de Plasminogênio/imunologia , Polimorfismo Genético , Sepse/diagnóstico
8.
J Intern Med ; 249(6): 511-8, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11422657

RESUMO

OBJECTIVES: To investigate the prognostic value of plasma fibrinogen level amongst middle-aged survivors of myocardial infarction (MI). DESIGN: Prospective cohort study. SETTINGS: Determination of fibrinogen and other prognostic variables in MI patients recruited in a presumably stable phase of coronary heart disease (CHD). SUBJECTS: A total of 247 middle-aged CHD patients (54 women and 193 men) who had their first MI at age < or = 60 (women) or < or = 55 (men) were recruited at least 3 months after (mean 2.1 years) the most recent MI. MAIN OUTCOME MEASURES: The primary endpoint was total mortality, and the secondary endpoint was cardiac deaths. The tertiary endpoint was major cardiac events (cardiac death, MI and cardiac arrest). RESULTS: During a follow-up period of 10 years a total of 44 patients had died, 36 from cardiac causes. Major cardiac event occurred in 70 patients. After adjusting for age, ejection fraction (EF), total serum cholesterol (TC), smoking and hypertension, patients in the top quartile of fibrinogen (> or = 4.0 g L-1) had a relative risk (RR) of 1.8 (95% CI 1.0-3.6) (P = 0.07) for death of all causes. The top quartile of fibrinogen was a stronger predictor of cardiac death; RR = 2.2 (95% CI 1.1-4.4) (P = 0.03), whilst the effect on the endpoint major cardiac event was not significant; RR=1.1 (95% CI 0.6-1.9) (P = 0.69). CONCLUSIONS: A plasma fibrinogen level in the top quartile predicted cardiac death in middle-aged patients who had suffered MI.


Assuntos
Fibrinogênio/análise , Infarto do Miocárdio/mortalidade , Feminino , Seguimentos , Humanos , Lipídeos/sangue , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Noruega/epidemiologia , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Estatísticas não Paramétricas , Volume Sistólico , Inquéritos e Questionários
9.
J Immunol Methods ; 252(1-2): 45-55, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11334964

RESUMO

After developing and applying a method for cryopreserving monocytes, we found a substantial cell loss when culturing these cells. Monocytes were isolated from blood donors by density gradient centrifugation, purified by elutriation and cryopreserved. Thawed cells were cultured in ultra low attachment wells and studied with Annexin V, Propidium iodide, Dihexyloxacarbocyanine (DiOC(6)(3)), bromolated deoxyuridine triphosphate nucleotides (Br-dUTP), DNA ploidy and DNA ladder methodologies. The main cell loss was within the first 24 h and recovery on day 7 was 35-40%. The first 2-6 h of culture were found to be crucial for determining which cells survive. Initially (2-4 h), apoptosis was the main feature but after 6 h, necrosis dominated. Two populations of cells developed after 24 h: "A" consisting of larger cells with low levels of apoptosis and necrosis signals and population "B" comprising smaller cells with a high expression of necrotic but low levels of apoptotic signals. Signs of DNA fragmentation were slight. These early, dynamic changes may be important for the interpretation of experimental results when investigating monocytes in culture.


Assuntos
Apoptose , Técnicas de Cultura de Células , Citometria de Fluxo , Monócitos/citologia , Necrose , Técnicas de Cultura de Células/métodos , Células Cultivadas , Criopreservação , Dano ao DNA , Citometria de Fluxo/métodos , Humanos , Fatores de Tempo
10.
Thromb Res ; 102(3): 273-83, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11369421

RESUMO

In the present study, we have shown that stimulation of cryopreserved, human peripheral blood monocytes with the cell wall components from Gram-negative bacteria, lipopolysaccharide (LPS), and from rapid-growing Mycobacterium sp., non-mannose-capped lipoarabinomannan (AraLAM), both induce expression of the "early immediate genes" tissue factor (TF) and tumor necrosis factor-alpha (TNF-alpha). This was demonstrated both at the protein and the mRNA levels. Antibodies against the CD14 receptor could block the stimulating effects. AraLAM was a significantly weaker inducer than LPS, and we speculate that this may reside in the number of the fatty acids in the part of the molecule that interacts with the CD14/Toll-like receptors (TLR). Finally, both LPS and AraLAM activated the "early immediate genes" through translocation of the transcription factor proteins NF-kappaB/Rel and increasing the binding activity of AP-1.


Assuntos
Genes Precoces/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Monócitos/efeitos dos fármacos , Tromboplastina/genética , Fator de Necrose Tumoral alfa/genética , Antígenos de Bactérias/farmacologia , Escherichia coli/química , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Monócitos/metabolismo , Mycobacterium/química , NF-kappa B/efeitos dos fármacos , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Tromboplastina/efeitos dos fármacos , Tromboplastina/metabolismo , Fator de Transcrição AP-1/efeitos dos fármacos , Fatores de Transcrição/efeitos dos fármacos , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
11.
Eur J Appl Physiol ; 84(4): 358-66, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11374121

RESUMO

Strenuous endurance exercise in fasted subjects is accompanied by increased plasma levels of catecholamines, leucocytosis, low insulin, and elevated plasma free fatty acids (FFA). Immediately after such exercise, plasma FFA may rise to high and potentially harmful levels, whereas the white blood cell count (WBCC) rapidly decreases towards or below baseline values. The present work investigated how active recovery (AR) for 15 min at 50% of maximal oxygen consumption (VO2max), after 60 min of uphill running at 83% of VO2max, influenced plasma FFA, lymphocyte, neutrophil, granulocyte, and monocyte count, as well as adrenaline, noradrenaline, insulin and cortisol concentrations until 120 min post-exercise. Thirteen endurance athletes participated in the study [24.2 (3.7) years, 1.82 (0.06) m, 76.7 (7.9) kg and VO2max 69.2 (6.8) ml min-1 kg-1]. In a randomized order, the subjects completed two sets of strenuous workouts, followed by either AR or complete rest in the supine position (RR). Compared with RR, AR strongly counteracted the rapid increase in plasma FFA 5 min post-exercise. The decreases in neutrophil and monocyte counts post-exercise were nullified by AR, and the cell count stayed above resting values throughout the observation period. AR also counteracted the rapid return of hormone concentration towards baseline levels. It would appear that active recovery at low intensity after strenuous exercise can maintain sufficient adrenergic activation to counteract the post-exercise drop in WBCC. However, in spite of keeping the catecholamine concentration high and insulin levels low, AR can also maintain a low plasma FFA concentration, probably because of the continued use of FFA in muscle. It remains to be elucidated whether the observed high FFA and low WBCC values after RR have a negative effect on health. If so, AR could be a preventive measure.


Assuntos
Epinefrina/sangue , Ácidos Graxos não Esterificados/sangue , Hidrocortisona/sangue , Norepinefrina/sangue , Resistência Física/imunologia , Adulto , Humanos , Insulina/sangue , Ácido Láctico/sangue , Contagem de Linfócitos , Monócitos/citologia , Neutrófilos/citologia , Corrida/fisiologia
12.
Methods Mol Med ; 67: 427-39, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-21337159

RESUMO

Lipopolysaccharides (LPS) located to the outer leaflet of the outer membrane have been identified as the main common endotoxic component of Gramnegative bacteria (1-3). Although other constituents of the bacterial cell wall, i.e., peptidoglycan, may contribute, LPS is considered to be the single most important constituent of Neisseria meningitidis that induces inflammation in the host (4-12). Neisserial lipopolysaccharides are often referred to as lipooligosaccharides (LOS) owing to the short polysaccharide chains comprising approx 10 sugars or less that are attached to lipid A.

13.
Scand J Clin Lab Invest ; 60(5): 357-65, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11003255

RESUMO

BACKGROUND: Monocyte purification by means of counter-current elutriation and subsequent cryopreservation for future use was initiated in 1986 and has been established as a routine since 1993. AIM: To sum up and evaluate our method for the isolation and preservation of monocytes. MATERIALS AND METHODS: Peripheral blood mononuclear cells (PBMC) were isolated from healthy donor blood by density gradient centrifugation, and monocytes were isolated from the PBMC by counter-current elutriation centrifugation using the Beckman J-6M/E centrifuge. The monocytes were then cryopreserved at 135 degrees C and thawed when required for experimental use. RESULTS: Results are given for the last 6 years, including 59 elutriations and the fractions containing monocytes. The mean purity of monocytes was 93% (range 64-98%); mean recovery was 51% (range 22-55%). Studies of CD14 expression and Annexin V indicate that there are no differences between elutriated fractions immediately upon purification or after freezing and thawing. The studies also indicate that interdonor variations are much larger than intradonor variations. DISCUSSION: Although it differs from other reports in certain respects, our procedure has nevertheless produced results in line with other findings. After extensive testing and use in different contexts we feel confident that we have established a method for producing a large number of purified and well-preserved monocytes. CONCLUSION: The goal of being able to perform a large number of experiments with monocytes of high purity and good functionality has been reached.


Assuntos
Separação Celular/métodos , Criopreservação/métodos , Monócitos/citologia , Anexina A5/análise , Contagem de Células Sanguíneas , Centrifugação com Gradiente de Concentração , Citometria de Fluxo , Humanos , Receptores de Lipopolissacarídeos/análise , Fatores de Tempo
14.
Thromb Haemost ; 83(6): 868-73, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10896240

RESUMO

The effect of aspirin on LPS-incubation of whole blood was investigated. Aspirin induced a concentration dependent increase (2.5-5-fold at 5 mM aspirin) in LPS-induced appearance of TNF-alpha and fibrinopeptide A (FPA) in plasma, despite the concomitant increase in the inhibitory cytokine IL-100. Aspirin substantially raised the levels of LPS-induced TF-mRNA and TNFalpha-mRNA in monocytes isolated from whole blood. The median ratio for TF-/beta-actin mRNA increased from 1.5 +/- 0.44 in the presence of LPS-alone, to 2.5 +/- 0.51 when 5 mM aspirin was added. The TNFalpha/beta-actin mRNA ratios were 1.8 +/- 0.4 and 5.5 +/- 2.7 respectively. Addition of exogenous PGE2 before incubation nearly abrogated the effect of aspirin on TNF-alpha, substantiating the role of PGE2 as a regulator of TNF-alpha synthesis, whereas the effect on FPA was small. Thus, in the presence of LPS in this whole blood model, aspirin apparently had a pro-inflammatory rather than an anti-inflammatory effect.


Assuntos
Aspirina/farmacologia , Fibrina/biossíntese , Lipopolissacarídeos/farmacologia , Fator de Necrose Tumoral alfa/biossíntese , Células Sanguíneas/química , Células Sanguíneas/efeitos dos fármacos , Células Sanguíneas/metabolismo , Dinoprostona/farmacologia , Relação Dose-Resposta a Droga , Fibrina/efeitos dos fármacos , Fibrinopeptídeo A/biossíntese , Fibrinopeptídeo A/efeitos dos fármacos , Humanos , Interleucina-10/biossíntese , Monócitos/química , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Fragmentos de Peptídeos/biossíntese , Fragmentos de Peptídeos/efeitos dos fármacos , Protrombina/biossíntese , Protrombina/efeitos dos fármacos , RNA Mensageiro/sangue , RNA Mensageiro/efeitos dos fármacos , Tromboplastina/genética , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética
15.
Clin Infect Dis ; 30(4): 643-7, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10770723

RESUMO

Thrombopoietin (TPO), interleukin (IL)-6, and platelets were measured serially in 9 patients with fulminant meningococcal septicemia and consumption coagulopathy. The results were compared with those of patients with meningococcal meningitis and mild meningococcemia (n=10) and with those of healthy control subjects (n=19). TPO levels in control subjects were below the detection limit (<63 pg/mL). In patients with fulminant meningococcal septicemia, the median TPO level on admission was 193 pg/mL (range, 133-401 pg/mL), and the level peaked within 3-7 days (median, 488 pg/mL; range, 239-1334 pg/mL). Platelet counts remained low, despite the elevated TPO levels. In patients with meningitis or meningococcemia, the median TPO level on admission was 112 pg/mL (range, <63-695 pg/mL), and the TPO level was not detectable within 48 h. Platelet counts for these patients remained within normal limits. Maximum IL-6 levels in patients with septicemia were observed on admission (median, 5317 pg/mL; range, 188-651,000 pg/mL) and increased earlier than TPO levels. In patients with fulminant septicemia, TPO level increases significantly whereas the level of circulating platelets does not.


Assuntos
Bacteriemia/sangue , Infecções Meningocócicas/sangue , Neisseria meningitidis , Trombopoetina/sangue , Adulto , Bacteriemia/metabolismo , Bacteriemia/microbiologia , Criança , Humanos , Interleucina-6/sangue , Infecções Meningocócicas/metabolismo , Infecções Meningocócicas/microbiologia , Contagem de Plaquetas
16.
Int J Sports Med ; 21(8): 608-12, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11156284

RESUMO

This study was conducted to examine the effects of different recovery regimens on white blood cell count (WBCC) and muscle enzyme activities following strenuous, submaximal, steady state workouts on a treadmill. Fourteen endurance trained, healthy, non-smoking college-aged males participated in the study. The workouts were followed by either 15-min of rest recovery (RR), or active recovery (AR). The AR consisted of running at 50% of VO2max whereas RR implied complete rest. Seven subjects completed two sets of 60-min running at 70% of VO2max (moderate intensity group, MI) followed by either RR or AR. The other seven completed two sets of 30-min running at 80% of VO2max (high intensity group, HI) followed by either RR or AR. Blood samples were drawn at rest, immediately after exercise, and at 15- and 120-min post-exercise (PE). Blood lactate concentrations increased throughout the running trials. Creatine kinase (CK), lactate dehydrogenase (LD), white blood cell count (WBCC) and thrombocyte count increased between rest and 0-min PE (p<0.05). Between 0-15-min PE, there were several significant differences between RR and AR in the HI-trial. RR was associated with a 35% reduction in WBCC, compared to only 6% decrease in AR (p<0.02). Neither during 15-120-min PE this period, nor in the 120-min sample alone, were there any significant differences in WBCC between the RR and AR experiments. In conclusion, the results show that AR as opposed to rest recovery prevents the initial 0-15-min PE fall in WBCC after strenuous endurance exercise.


Assuntos
Exercício Físico/fisiologia , Resistência Física/imunologia , Descanso , Adulto , Creatina Quinase/análise , Creatina Quinase/metabolismo , Fadiga , Humanos , L-Lactato Desidrogenase/análise , L-Lactato Desidrogenase/metabolismo , Contagem de Leucócitos , Masculino , Consumo de Oxigênio
17.
J Endotoxin Res ; 6(6): 437-45, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11521068

RESUMO

Neisseria meningitidis, the cause of epidemic meningitis and acute lethal sepsis, synthesizes surplus lipopolysaccharides (LPSs) during growth, which are released as outer membrane vesicles (OMV) or "blebs". Meningococcal disease severity is related to plasma LPS levels. We have compared the biological activities of native outer membrane vesicles (nOMV) to those of purified Nm-LPS (Nm-LPS) and LPS-depleted OMV (dOMV) prepared from N. meningitidis. The LPS content of nOMV was determined spectrophotometrically by quantifying KDO and by silver-stained SDS-PAGE gels. The morphology of the preparations was studied by transmission electron microscopy. The Limulus amoebocyte lysate (LAL) assay was used to quantify LPS in the plasma solutions. The preparations were diluted in endotoxin-free heparin plasma to equal amounts of LPS (w/w) in the range 50-5000 pg/ml. The biological reactivity was tested by: (i) a monocyte target-assay (monocyte purity > or =96%); and (ii) a whole blood model, measuring the secretion of TNF-alpha and IL-6 induction of procoagulant activity in monocytes (PCA). In both models, nOMV induced dose-dependent cell responses (TNF-alpha, IL-6, PCA) similar to purified Nm-LPS, whereas dOMV induced minimal responses. However, LAL activity was significantly higher for nOMV than for purified Nm-LPS and dOMV. The cellular responses of purified Nm-LPS and nOMV were reduced (>95%) by a specific anti-CD14-antibody.


Assuntos
Lipopolissacarídeos/toxicidade , Neisseria meningitidis/patogenicidade , Adulto , Membrana Celular/química , Membrana Celular/ultraestrutura , Humanos , Técnicas In Vitro , Interleucina-6/biossíntese , Teste do Limulus , Receptores de Lipopolissacarídeos/sangue , Lipopolissacarídeos/isolamento & purificação , Microscopia Eletrônica , Modelos Biológicos , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Neisseria meningitidis/química , Neisseria meningitidis/ultraestrutura , Fator de Necrose Tumoral alfa/biossíntese
18.
J Cardiovasc Pharmacol ; 34(4): 584-8, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10511135

RESUMO

Elevated levels of endothelin-1 (ET-1) and von Willebrand factor (vWF), both markers indicative of endothelial function, are associated with hypertension. In a randomized open study we investigated the effect of antihypertensive treatment with the alpha-blocker doxazosin (n = 23) or the beta-blocker atenolol (n = 22) for 22 weeks on circulating levels of ET-1 and vWF in middle-aged men with essential hypertension. Blood pressure reduction was satisfactorily achieved with both drugs, although the decrease in the atenolol group was larger than that in the doxazosin group. A reduction in the levels of vWF occurred in both groups, being more pronounced in the alpha-blocker group compared with the decrease on beta blockers, p = 0.004 and p = 0.056, respectively. In the alpha-blocker group, there was a significant correlation (r = 0.50, p = 0.022) between the reduction in diastolic blood pressure and the decline in vWF. A highly significant decrease in plasma ET-1 was obtained during beta blockade (p = 0.007), whereas no significant change occurred within the alpha-blocker group. There was, however, no correlation between the decrease in blood pressure and the reduction in ET-1. The different favorable effects of alpha and beta blockers on endothelial function expressed as vWF and ET-1, could indicate that the effects are probably related not only to the blood pressure per se, but also to the different pharmacologic mechanisms of the drugs.


Assuntos
Atenolol/farmacologia , Doxazossina/farmacologia , Endotelina-1/sangue , Hipertensão/patologia , Fator de von Willebrand/metabolismo , Antagonistas Adrenérgicos alfa/farmacologia , Antagonistas Adrenérgicos beta/farmacologia , Adulto , Anti-Hipertensivos/farmacologia , Biomarcadores , Pressão Sanguínea/efeitos dos fármacos , Endotélio/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Método Simples-Cego
20.
Thromb Haemost ; 81(4): 566-70, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10235440

RESUMO

Omega-3 fatty acids (n-3 FA) may reduce atherogenesis and thrombosis. We investigated the effects of n-3 FAs on procoagulant activity and cytokine expression in whole blood cultures from patients with atherosclerosis. Eleven of the 23 included patients had received 5.1 g n-3 FA daily for 6 months (group I) whereas 12 patients had been on placebo (group II). All patients were then given 5. g n-3 FA daily for another 4 weeks. At baseline significantly lower levels of LPS-induced prothrombin fragment1+2 were found in group I (p = 0.010), this difference being eliminated after 4 weeks. Il-6 and TNFalpha were significantly higher at baseline in group I and the differences in changes from baseline between the groups were statistically highly significant with increasing values in group II(Il-6 p = 0.001, TNF alpha p = 0.002). The present results indicate a reduction in pro-thrombotic potential in patients receiving highly concentrated n-3 FA, whereas some proinflammatory responses might be adverse.


Assuntos
Arteriosclerose/sangue , Arteriosclerose/tratamento farmacológico , Citocinas/sangue , Fator VIII , Ácidos Graxos Ômega-3/uso terapêutico , Adulto , Idoso , Contagem de Células Sanguíneas , Método Duplo-Cego , Fator VIII/efeitos dos fármacos , Ácidos Graxos/sangue , Feminino , Humanos , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Lipoproteínas/sangue , Masculino , Pessoa de Meia-Idade , Fosfolipídeos/sangue , Vitamina E/sangue
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