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41.
Initiation of the extrinsic pathway of coagulation by human and rabbit alveolar macrophages: a kinetic study 总被引:3,自引:0,他引:3
We examined assembly and expression of the factor X activating complex on human and rabbit alveolar macrophages. Kinetic parameters of the factor X activating reaction were determined by functional titrations of factors VII and X with macrophage tissue factor (TF) added. We found rapid activation of factor X to Xa on alveolar macrophage surfaces. Detection of rapid factor Xa formation on macrophages required addition of exogenous factors VII and X. At plasma concentrations of the purified factors, factor Xa was formed on freshly isolated macrophages at approximately 5.4 pmol/min/10(6) cells. After macrophage maturation in culture for 20 hours with LPS (endotoxin) added, the factor X activation rate was increased two- to sixfold. The km' (apparent km) of TF-factor VII enzymatic complexes assembled on alveolar macrophages for factor X were (258 +/- 55 and 475 +/- 264 nmol/L for human and rabbit cells, respectively). The km' did not change during macrophage maturation in culture, but V'max (apparent Vmax) was consistently increased. The K1/2 of human factor VII (concentrations giving half maximal rates of factor X activation) for the interaction with human and rabbit alveolar macrophage TF were 0.191 +/- 0.096 and 1.7 +/- 0.7 etamol/L, respectively. The K1/2 were not significantly changed after maturation, whereas rates of Xa formation at saturation with factor VII were increased. The fast rates of factor X activation observed at physiologic concentrations of plasma-derived factors VII and X indicate that TF on alveolar macrophages is likely to provide sites for binding of factor VII and activation of factor X in vivo during clotting reactions associated with alveolar edema and inflammation. 相似文献
42.
Jianjun Wang Sanna Ruotsalainen Leena Moilanen P?ivi Lepist? Markku Laakso Johanna Kuusisto 《European heart journal》2007,28(7):857-864
AIMS: The metabolic syndrome (MetS) is defined as a clustering of cardiovascular risk factors characterized by insulin resistance. We investigated the relationship of the MetS and its single components, defined by all six different criteria, with coronary heart disease (CHD), cardiovascular disease (CVD), and all-cause mortality in a prospective population-based study. METHODS AND RESULTS: The MetS was defined according to the World Health Organization (WHO), the European Group for the Study of Insulin Resistance (EGIR), the National Cholesterol Education Program (NCEP), the American College of Endocrinology (ACE), the International Diabetes Federation (IDF), and the American Heart Association (updated NCEP) criteria. We investgated the relationship of the MetS defined by aforementioned six criteria with CHD, CVD, and all-cause mortality with Cox regression analyses in a non-diabetic Finnish population of 1025 subjects, aged 65-74 years, during the 13-year follow-up. The MetS defined by all aforementioned criteria was associated with a statistically significant risk for CVD mortality when adjusted for all confounding variables (Hazards Ratios, HRs from 1.31 to 1.51). The MetS defined by the WHO, ACE, and IDF criteria was associated with an increased risk of CHD mortality (HRs from 1.42 to 1.58). There was no association between the MetS by any criteria and all-cause mortality. Of the single components of the MetS, the following predicted CVD mortality in multivariable models: impaired fasting glucose by the WHO, NCEP, and ACE criteria (HR 1.34) and by the IDF and updated NCEP criteria (HR 1.29); impaired glucose tolerance by the WHO and ACE criteria (HR 1.55); low HDL cholesterol by the EGIR criteria (HR 1.50) and by the NCEP, IDF, and updated NCEP criteria (HR 1.29); and microalbuminuria according to the WHO definition (HR 1.86). CONCLUSION: The MetS defined by all six current criteria predicts CVD mortality in elderly subjects. However, of the single components of the MetS, IFG, IGT, low HDL cholesterol, and microalbuminuria predicted CVD mortality with equal or higher HRs when compared with the different definitions of the MetS. Therefore, our study suggests that the MetS is a marker of CVD risk, but not above and beyond the risk associated with its individual components. 相似文献
43.
Päivä H Laakso J Laine H Laaksonen R Knuuti J Raitakari OT 《Journal of the American College of Cardiology》2002,40(7):1241-1247
OBJECTIVE: The goal of this study was to examine the relationship between plasma asymmetric dimethylarginine (ADMA) level and hyperemic myocardial blood flow (MBF) in subjects with borderline hypertension (BHT) and familial hypercholesterolemia (FH). METHODS: Asymmetric dimethylarginine is an endogenous competitive inhibitor of nitric oxide synthase that may modulate vascular function.We measured plasma ADMA levels and myocardial flow in 77 young men (mean age 35 +/- 5 years), including 47 healthy controls, 16 men with BHT, and 14 men with FH. Basal and dipyridamole-induced myocardial flow was measured using positron emission tomography. Plasma ADMA levels were measured using high-pressure liquid chromatography. RESULTS: Asymmetric dimethylarginine levels were significantly elevated in the BHT group compared with controls (0.59 +/- 0.13 micromol/l vs. 0.43 +/- 0.12 micromol/l, p < 0.001), and they had significantly lower dipyridamole flow (2.85 +/- 1.20 ml/min/g vs. 3.69 +/- 1.68 ml/min/g, p < 0.05). In a multivariate regression model adjusted for the study group, dipyridamole flow was inversely associated with ADMA (p < 0.05), age (p < 0.05), and apolipoprotein B concentration (p < 0.05). CONCLUSIONS: We conclude that plasma ADMA concentration is related to dipyridamole-induced vasodilatory function in young men, independently of blood pressure elevation and hypercholesterolemia. Subjects with BHT have significantly increased plasma ADMA levels, which may partly explain the impaired hyperemic MBF in this condition. 相似文献
44.
Miettinen H.; Lehto S.; Saikku P.; Haffner S. M.; Ronnemaa T.; Pyorala K.; Laakso M. 《European heart journal》1996,17(5):682-688
OBJECTIVE: It has been suggested that Chlamydia pneumoniae, a Gram-negativeintracellular bacterium, is a risk factor for both myocardialinfarction and chronic coronary heart disease. Previous studieshave been done predominantly in non-diabetic subjects and thusthe effect of diabetes on the association between C. pneumontaeantibodies and coronary heart disease has not been analysed.The aim of our study was to investigate the association betweenprior chlamydial infection and the risk of serious coronaryheart disease events (myocardial infarction or coronary death)in a 7-year prospective study of cohorts of diabetic and non-diabeticsubjects in two areas of Finland. RESULTS: It was found that the prevalence of elevated chlamydial antibodiesat baseline was higher in non-diabetic subjects who had seriouscoronary heart disease events during the follow-up than in subjectswithout coronary heart disease events (32 vs 15%, relative risk2·56, P=0·013) in East Finland. In non-diabeticsubjects living in West Finland we did not find this association.The association between the C pneumoniae antibodies and coronaryheart disease events did not markedly change after controllingfor other risk factors for coronary heart disease (OR 2·44,P=0·055) in non-diabetic subjects living in eastern Finland.In diabetic patients we did not find any association betweenchlamydial antibodies and coronary heart disease events. CONCLUSION: We found an association between C. pneumoniae antibodies andcoronary heart disease events in non-diabetics living in easternFinland. This association remained strong even after controllingfor the other risk factors for coronary heart disease. In diabeticpatients with high risk for coronary heart disease, C. pneumnoniaewas not a risk factor for coronary heart disease.(Eur HeartJ 1996; 17: 682688) 相似文献
45.
Factors affecting the transduction of pluripotent hematopoietic stem cells: long-term expression of a human adenosine deaminase gene in mice 总被引:5,自引:0,他引:5
An amphotropic retroviral vector, LgAL(delta Mo + PyF101) containing a human adenosine deaminase (ADA) cDNA was used to optimize procedures for the lasting genetic modification of the hematopoietic system of mice. The highest number of retrovirally infected cells in the hematopoietic tissues of long-term reconstituted mice was observed after transplantation of bone marrow (BM) cells that had been cocultured in the presence of both interleukin-1 alpha (IL-1 alpha) and IL-3. A significantly lower number was detected when IL-1 alpha was omitted from such cocultures. The yield of cells that generate spleen colony-forming cells (CFU-S) in the BM of lethally irradiated recipients (MRA-CFU-S) significantly improved on inclusion of the adherent cell fraction of cocultures in the transplant. Retroviral integration patterns in MRA-CFU-S-derived spleen colonies showed that an MRA-CFU-S can produce many CFU-S during BM regeneration. Expression of hADA was detected in the circulating white blood cells of long-term reconstituted animals, demonstrating that the LgAL(delta Mo + PyF101) vector is capable of directing the sustained expression of hADA, and in approximately 35% of the transduced MRA-CFU-S-derived spleen colonies. These results should facilitate the development of gene therapy protocols for the treatment of severe combined immunodeficiency caused by a lack of functional ADA. 相似文献
46.
Noriaki Moriyama Teemu Laakso Peter Raivio Sebastian Dahlbacka Eeva-Maija Kinnunen Tatu Juvonen Antti Valtola Annastiina Husso Maina P. Jalava Tuomas Ahvenvaara Tuomas Tauriainen Jarkko Piuhola Asta Lahtinen Matti Niemelä Timo Mäkikallio Marko Virtanen Pasi Maaranen Markku Eskola Mika Laine 《The Canadian journal of cardiology》2021,37(1):37-46
BackgroundThe data on acute kidney injury (AKI) in patients without chronic kidney disease (CKD) after transcatheter aortic valve replacement (TAVR) are limited. The study sought to compare the incidence of AKI and its impact on 5-year mortality after TAVR and surgical aortic valve replacement (SAVR) in patients without CKD.MethodsThis registry included data from 6463 consecutive patients who underwent TAVR or SAVR. CKD was defined as estimated glomerular filtration rate <60 mL/min/1.73 m2. AKI was defined according to the Kidney Disease Improving Global Outcomes criteria. For sensitivity analysis, propensity-score matching between TAVR and SAVR was performed.ResultsThe study included 4555 consecutive patients (TAVR, n = 1215 and SAVR, n = 3340) without CKD. Propensity-score matching identified 542 pairs. Patients who underwent TAVR had a significantly lower incidence of AKI in comparison to those who underwent SAVR (unmatched 4.7% vs 16.4%, P < 0.001, multivariable analysis: odds ratio, 0.29, 95% confidence interval [CI], 0.20-0.41; matched 5.9% vs 19.0%, P < 0.001). Patients with AKI had significantly increased 5-year mortality compared with those without AKI (unmatched 36.0% vs 19.1%, log-rank P < 0.001; matched 36.3% vs 24.0%, log-rank P < 0.001). The adjusted hazard ratios for 5-year mortality were 1.58 (95% CI, 1.20-2.08) for AKI grade 1, 3.27 (95% CI, 2.09-5.06) for grade 2, and 4.82 (95% CI, 2.93-8.04) for grade 3.ConclusionsTAVR in patients without CKD was associated with a significantly less frequent incidence of AKI compared with SAVR. AKI significantly increased the risk of 5-year mortality after either TAVR or SAVR, and increasing severity of AKI was incrementally associated with 5-year mortality. 相似文献
47.
Siitonen N Lindström J Eriksson J Valle TT Hämäläinen H Ilanne-Parikka P Keinänen-Kiukaanniemi S Tuomilehto J Laakso M Uusitupa M 《Diabetologia》2004,47(8):1416-1424
Aims/hypothesis Impaired insulin secretion has a strong genetic component. In this study we investigated whether the 12Glu9 polymorphism in the gene encoding the 2B-adrenergic receptor (ADRA2B) is associated with insulin secretion and/or the incidence of Type 2 diabetes in individuals with impaired glucose tolerance.Methods We investigated a total of 506 subjects with impaired glucose tolerance participating in the Finnish Diabetes Prevention Study (DPS). Participants were randomly assigned to an intervention group or a control group. Anthropometric measurements and an oral glucose tolerance test were performed at baseline and at annual follow-up. In a subgroup of patients (n=83), a frequently sampled intravenous glucose tolerance test (FSIGT) was performed at baseline.Results All patients had similar anthropometric measurements and insulin and glucose levels at baseline. Multiple logistic regression analysis revealed significant interaction (p=0.003) between study group and genotype across the entire study population. In the control group, subjects with the Glu9 allele had an increased risk of developing Type 2 diabetes compared with subjects with the Glu12/12 genotype (odds ratio [OR]=2.68, 95% CI 1.02–7.09, p=0.047 for Glu12/12, and OR=5.17, 95% CI 1.76–15.21, p=0.003 for Glu9/9). This increased risk was not observed in the intervention group, who showed significant weight loss during the trial. In the subgroup who underwent the FSIGT, subjects with the Glu9/9 genotype showed the lowest acute insulin response (p=0.005 for trend).Conclusions/interpretation The 12Glu9 polymorphism of ADRA2B is associated with impaired first-phase insulin secretion and may predict the development of Type 2 diabetes in subjects with impaired glucose tolerance who are not subjected to a lifestyle intervention.Abbreviations AIR acute insulin response - AR adrenergic receptor - BMR basal metabolic rate - DI disposition index - DPS the Finnish Diabetes Prevention Study - FSIGT frequently sampled intravenous glucose tolerance test - OR odds ratio - SG glucose effectiveness - SI insulin sensitivity index 相似文献
48.
Journal of Autism and Developmental Disorders - This paper analyses disfluencies and ungrammatical expressions in the speech of 11–13-year-old Finnish-speaking boys with ASD... 相似文献
49.
Enhancement of neutrophil function by granulocyte-macrophage colony- stimulating factor involves recruitment of a less responsive subpopulation 总被引:3,自引:0,他引:3
Human granulocyte-macrophage colony-stimulating factor (GM-CSF) enhances numerous functions of mature neutrophils (PMN) including phagocytosis, superoxide responses to chemotaxins, antibody-dependent cellular cytotoxicity, and expression of complement receptors. A central question concerns whether the mechanism of enhancement involves quantitative increases in the response of all cells v subpopulation recruitment. The effects of GM-CSF on individual cell light scatter changes, membrane potential, and oxidant responses induced by the chemoattractant N-formyl-methionyl-leucyl-phenylalanine (FMLP) were assessed by flow cytometry and by scoring individual cells for nitroblue tetrazolium dye (NBT) reduction. GM-CSF produced a dose- and time-dependent shift in forward light scatter that was very similar in character to that seen with FMLP or leukotriene B4 stimulation. Although not capable of depolarizing the cells directly, GM-CSF primed PMNs for enhanced membrane potential responses to FMLP by significantly increasing the proportion of depolarizing cells when compared with diluent-treated controls after a 60-minute incubation at 37 degrees C (79.4% +/- 3.4% v 29.5% +/- 4.7% GM-CSF v diluent, mean +/- SE, P less than .005, n = 11). Subpopulation recruitment by GM-CSF treatment was also demonstrated by the FMLP-elicited NBT test. Taken together, these results indicate that GM-CSF can modulate the function of mature PMN by enhancing the proportion of responsive cells. 相似文献
50.
Bash RO; Crist WM; Shuster JJ; Link MP; Amylon M; Pullen J; Carroll AJ; Buchanan GR; Smith RG; Baer R 《Blood》1993,81(8):2110-2117
Alteration of the TAL1 locus is the most common nonrandom genetic defect in childhood T-cell acute lymphoblastic leukemia (T-ALL). To determine if rearrangements of the TAL1 proto-oncogene confer a distinct leukemic phenotype, we studied leukemic peripheral blood or bone marrow samples from 182 children with newly diagnosed T-ALL enrolled on Pediatric Oncology Group treatment protocols. Forty-eight (26%) of the samples had a local rearrangement of the TAL1 locus. Demographic and clinical features were compared for patient subgroups with and without TAL1 rearrangements. The only clinical correlates that were significantly associated with TAL1 gene rearrangements were higher white blood cell count (P = .017) and higher hemoglobin (P = .007) at diagnosis. Immunophenotypically, samples with altered TAL1 were more likely to be CD2+ (P = .001) and lack CD10 (cALLa) expression (P = .007) than those without the rearrangement. There was a trend toward improved event-free survival (EFS) in patients with TAL1 rearrangements (4-year EFS was 44% +/- 7% for patients without the rearrangements v 59% +/- 11% for those with rearrangements), but the difference was not significant (P = .34). The role of TAL1 in leukemogenesis has yet to be clearly defined, and the prognostic significance of TAL1 gene rearrangements in T-ALL deserves further study. 相似文献