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1.
Eur Rev Med Pharmacol Sci ; 25(3): 1511-1521, 2021 02.
Article in English | MEDLINE | ID: mdl-33629320

ABSTRACT

OBJECTIVE: Coronary artery bypass grafting (CABG) seems to present a powerful trigger of oxidative stress (OS) and acute inflammatory response. This study aimed to estimate the effects of off-pump coronary artery bypass (OPCAB) grafting on the OS that is commonly observed in patients undergoing operation under cardiopulmonary bypass (CPB). Additionally, we aimed to examine the relationship between and paraoxonase 1 (PON1) activity and the degree of stenosis, severity and complexity of the atherosclerotic lesions, estimated by SYNTAX score (SS). PATIENTS AND METHODS: Study group of 107 patients scheduled for CABG were divided into CPB and OPCAB group. Blood samples for OS markers measurement were collected at six-time intervals: before skin incision (t1), immediately after surgery (t2), 6h (t3), 24h (t4), 48h (t5) and 96h after cessation of the operation and surgical trauma (t6). SS was calculated. RESULTS: A significant decrease in lipid hydroperoxides (LOOH) and advanced oxidation protein products (AOPP) levels after both types of surgeries were observed, whereas PON1 reduction was observed higher in the CPB than in the OPCAB group. A significant inverse correlation between SS values and PON1 activity, preoperatively and during the early postoperative hours after surgery [in t2, t3 time intervals (p<0.05 for all)] was found. ROC analysis showed that for CPB patients, Model with all OS parameters showed excellent accuracy (AUC=0.957, p<0.001) for prediction postoperative complications. CONCLUSIONS: Decrease in PON1 activity during the early post-operative phases was related to higher SS. This relationship was more convincing in CPB, compared with OPCAB patients. Moreover, integrated models of OS status parameters have the capability to predict the development of postoperative complications.


Subject(s)
Aryldialkylphosphatase/metabolism , Cardiopulmonary Bypass/adverse effects , Coronary Artery Bypass/adverse effects , Postoperative Complications/metabolism , Cohort Studies , Female , Humans , Male , Middle Aged , Prospective Studies
2.
Biol Sex Differ ; 11(1): 36, 2020 07 06.
Article in English | MEDLINE | ID: mdl-32631423

ABSTRACT

BACKGROUND: Studies have recently examined the role of epigenetic mechanisms in preeclampsia pathophysiology. One commonly examined epigenetic process is DNA methylation. This heritable epigenetic marker is involved in many important cellular functions. The aim of this study was to establish the association between DNA methylation and preeclampsia and to critically appraise the roles of major study characteristics that can significantly impact the association between DNA methylation and preeclampsia. MAIN BODY: A systematic review was performed by searching PubMed, Web of Science, and EMBASE for original research articles published over time, until May 31, 2019 in English. Eligible studies compared DNA methylation levels in pregnant women with vs. without preeclampsia. Ninety articles were included. Epigenome-wide studies identified hundreds of differentially methylated places/regions in preeclamptic patients. Hypomethylation was the predominant finding in studies analyzing placental tissue (14/19), while hypermethylation was detected in three studies that analyzed maternal white blood cells (3/3). In candidate gene studies, methylation alterations for a number of genes were found to be associated with preeclampsia. A greater number of differentially methylated genes was found when analyzing more severe preeclampsia (70/82), compared to studies analyzing less severe preeclampsia vs. controls (13/27). A high degree of heterogeneity existed among the studies in terms of methodological study characteristics including design (study design, definition of preeclampsia, control group, sample size, confounders), implementation (biological sample, DNA methylation method, purification of DNA extraction, and validation of methylation), analysis (analytical method, batch effect, genotyping, and gene expression), and data presentation (methylation quantification measure, measure of variability, reporting). Based on the results of this review, we provide recommendations for study design and analytical approach for further studies. CONCLUSIONS: The findings from this review support the role of DNA methylation in the pathophysiology of preeclampsia. Establishing field-wide methodological and analytical standards may increase value and reduce waste, allowing researchers to gain additional insights into the role of DNA methylation in the pathophysiology of preeclampsia.


Subject(s)
DNA Methylation , Epigenesis, Genetic , Pre-Eclampsia/genetics , Pre-Eclampsia/physiopathology , Female , Genetic Predisposition to Disease , Humans , Pregnancy
3.
Reprod Domest Anim ; 53(4): 947-954, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29740884

ABSTRACT

Foetal sex determination using polymerase chain reaction (PCR) in mammals is based on the amplification of gender-specific foetal DNA sequences circulating in maternal blood. The bovine synepitheliochorial placenta does not allow a direct contact between the trophoblast and the maternal blood, resulting in difficult passage of foetal DNA and, consequently, its very small amounts in maternal bloodstream. Circulating cell-free foetal DNA (ccffDNA) encompasses short nucleotide fragments (300-600 bp) in maternal circulation. The aim of this study was to assess this non-invasive method in accurate prenatal sexing in early and late gestational periods in comparison with ultrasound diagnostics. As various DNA isolation and amplification methods were tested, their success in obtaining reliable results was evaluated. Two groups were tested, each consisting of 20 pregnant cows. Blood of a bull and a non-pregnant heifer was the controls. Extraction of foetal DNA was accomplished by three different methods: using tubes with silicone membranes, a single-tube extraction without silicone membranes and phenol-chloroform extraction. Following each extraction method, foetal DNA was amplified using PCR and real-time PCR with both bAML and TSPY primers in a separate reaction. Positive results were obtained only after amplification of foetal DNA extracted with a single-tube extraction kit. In comparison with ultrasound examination results and foetal gender recorded at birth, the sensitivity of the PCR test was 90% in Group I, but the technique failed to detect male foetuses in Group II. The real-time PCR test sensitivity in Group I was 90% and in Group II 91.6%.


Subject(s)
DNA/genetics , Polymerase Chain Reaction/veterinary , Sex Determination Analysis/veterinary , Animals , Cattle , Female , Male , Polymerase Chain Reaction/methods , Pregnancy , Reproduction , Ultrasonography, Prenatal/veterinary
4.
Opt Express ; 25(9): 10090-10102, 2017 May 01.
Article in English | MEDLINE | ID: mdl-28468384

ABSTRACT

The self-structuring of laser light in an artificial optical medium composed of a colloidal suspension of nanoparticles is demonstrated using variational and numerical methods extended to dissipative systems. In such engineered materials, competing nonlinear susceptibilities are enhanced by the light induced migration of nanoparticles. The compensation of diffraction by competing focusing and defocusing nonlinearities, together with a balance between loss and gain, allow for self-organization of light and the formation of stable dissipative breathing vortex solitons. Due to their robustness, the breathers may be used for selective dynamic photonic tweezing of nanoparticles in colloidal nanosuspensions.

5.
Phlebology ; 29(2): 98-104, 2014 Mar.
Article in English | MEDLINE | ID: mdl-22987234

ABSTRACT

OBJECTIVES: Condition known as chronic cerebrospinal venous insufficiency (CCSVI) is characterized by insufficient cerebral vein drainage in patients with multiple sclerosis (MS) and internal jugular vein (IJV), vertebral and/or azygos veins stenoses. However, external compression on the IJV was not clearly described as a potential cause of CCSVI. We aim to present a case of CCSVI in a patient with MS caused by bilateral IJV inverted valves combined with IJV external compression by carotid bulb. METHODS: A 31-year-old female patient was admitted to our institute for IJV and vertebral veins morphological and haemodynamical assessment after being treated for MS for the last 14 years. Colour Doppler ultrasonography showed right IJV prestenotic dilation and inverted valves in both IJV. Computerized tomography angiography showed bilateral IJV compression by carotid bulb. Haemodynamical Doppler parameters showed that external IJV compression significantly contributed to CCSVI occurrence. RESULTS: Bilateral IJV confluence percutaneous angioplasty (PTA) was done, and the patient was discharged for further neurological examination. Partial carbon dioxide pressure was significantly lower in the distal part of both IJV following PTA and oxygen saturation increased. CONCLUSION: In the case presented, PTA of the IJV confluence resulted in haemodynamic improvement despite the presence of IJV external compression.


Subject(s)
Jugular Veins/diagnostic imaging , Multiple Sclerosis/physiopathology , Venous Insufficiency/physiopathology , Adult , Angiography , Angioplasty , Azygos Vein/physiopathology , Female , Hemodynamics , Humans , Lasers , Multiple Sclerosis/complications , Oxygen/chemistry , Pressure , Tomography, X-Ray Computed , Ultrasonography, Doppler , Venous Insufficiency/complications
6.
Vasa ; 40(6): 474-81, 2011 Nov.
Article in English | MEDLINE | ID: mdl-22090181

ABSTRACT

BACKGROUND: To evaluate safety, short and long-term graft patency, clinical success rates, and factors associated with patency, limb salvage and mortality after surgical reconstruction in patients younger than 50 years of age who had undergone unilateral iliac artery bypass surgery. PATIENTS AND METHODS: From January 2000 to January 2010, 65 consecutive reconstructive vascular operations were performed in 22 women and 43 men of age < 50 years with unilateral iliac atherosclerotic lesions and claudication or chronic limb ischemia. All patients were followed at 1, 3, 6, and 12 months after surgery and every 6 months thereafter. RESULTS: There was in-hospital vascular graft thrombosis in four (6.1 %) patients. No in-hospital deaths occurred. Median follow-up was 49.6 ± 33 months. Primary patency rates at 1-, 3-, 5-, and 10-year were 92.2 %, 85.6 %, 73.6 %, and 56.5 %, respectively. Seven patients passed away during follow-up of which four patients due to coronary artery disease, two patients due to cerebrovascular disease and one patient due to malignancy. Limb salvage rate after 1-, 3-, 5-, and 10-year follow-up was 100 %, 100 %, 96.3 %, and 91.2 %, respectively. Cox regression analysis including age, sex, risk factors for vascular disease, indication for treatment, preoperative ABI, lesion length, graft diameter and type of pre-procedural lesion (stenosis/occlusion), showed that only age (beta - 0.281, expected beta 0.755, p = 0.007) and presence of diabetes mellitus during index surgery (beta - 1.292, expected beta 0.275, p = 0.026) were found to be significant predictors of diminishing graft patency during the follow-up. Presence of diabetes mellitus during index surgery (beta - 1.246, expected beta 0.291, p = 0.034) was the only variable predicting mortality. CONCLUSIONS: Surgical treatment for unilateral iliac lesions in patients with premature atherosclerosis is a safe procedure with a low operative risk and acceptable long-term results. Diabetes mellitus and age at index surgery are predictive for low graft patency. Presence of diabetes is associated with decreased long-term survival.


Subject(s)
Arterial Occlusive Diseases/surgery , Atherosclerosis/surgery , Blood Vessel Prosthesis Implantation , Graft Occlusion, Vascular/etiology , Iliac Artery/surgery , Ischemia/surgery , Leg/blood supply , Limb Salvage , Adult , Arterial Occlusive Diseases/mortality , Atherosclerosis/mortality , Cause of Death , Female , Follow-Up Studies , Graft Occlusion, Vascular/mortality , Humans , Ischemia/mortality , Male , Middle Aged , Proportional Hazards Models , Risk Factors , Survival Rate
7.
Phys Rev Lett ; 105(21): 213901, 2010 Nov 19.
Article in English | MEDLINE | ID: mdl-21231306

ABSTRACT

Using a combination of the variation approximation and direct simulations, we consider the model of the light transmission in nonlinearly amplified bulk media, taking into account the localization of the gain, i.e., the linear loss shaped as a parabolic function of the transverse radius, with a minimum at the center. The balance of the transverse diffraction, self-focusing, gain, and the inhomogeneous loss provides for the hitherto elusive stabilization of vortex solitons, in a large zone of the parameter space. Adjacent to it, stability domains are found for several novel kinds of localized vortices, including spinning elliptically shaped ones, eccentric elliptic vortices which feature double rotation, spinning crescents, and breathing vortices.

8.
Cerebrovasc Dis ; 28(6): 589-94, 2009.
Article in English | MEDLINE | ID: mdl-19844099

ABSTRACT

BACKGROUND: Previous data are conflicting as to whether imbalance between hemostatic factors is associated with clinical strokes. We evaluated the association between hemostatic factor levels and subclinical lacunar infarcts in a nested sample from a subset of the Atherosclerosis Risk in Communities (ARIC) cohort. METHODS: 196 cases without clinical strokes had lacunar infarcts by MRI, and 214 controls without radiographic infarcts were frequency-matched by age group and sex. Logistic regression models were fitted to assess the association between levels of hemostatic markers and case status. RESULTS: In age-, race- and sex-adjusted models, von Willebrand factor (vWF) and D-dimer were positively associated with case status, with odds ratios for the highest vs. lowest tertile of 2.0 (95% CI 1.2-3.6) for vWF and 1.76 (95% CI 1.02-3.0) for D-dimer. Plasminogen had nonsignificant inverse associations with presence of silent lacunar infarcts. CONCLUSIONS: vWF and D-dimer were positively associated, and plasminogen was nonsignificantly inversely associated with subclinical radiographic infarct. Further studies on the role of these hemostatic factors in the development of silent lacunar infarcts may help elucidate the mechanisms behind this injury and may even point to potential targets for future intervention.


Subject(s)
Brain Infarction/blood , Brain Infarction/epidemiology , Fibrin Fibrinogen Degradation Products/metabolism , Plasminogen/metabolism , von Willebrand Factor/metabolism , Atherosclerosis/epidemiology , Biomarkers/blood , Brain Infarction/pathology , Case-Control Studies , Cross-Sectional Studies , Female , Humans , Logistic Models , Magnetic Resonance Imaging , Male , Middle Aged , Predictive Value of Tests , Retrospective Studies , Risk Factors , United States/epidemiology
9.
Opt Express ; 17(14): 11698-709, 2009 Jul 06.
Article in English | MEDLINE | ID: mdl-19582084

ABSTRACT

Dynamical and steady-state behavior of beams propagating in nematic liquid crystals (NLCs) is analyzed. A well-known model for the beam propagation and the director reorientation angle in a NLC cell is treated numerically in space and time. The formation of steady-state soliton breathers in a threshold region of beam intensities is displayed. Below the region the beams diffract, above the region spatiotemporal instabilities develop, as the input intensity and the material parameters are varied. Curiously, the only kind of solitons we could demonstrate in our numerical studies was the breathers. Despite repeated efforts, we could not find the solitons with a steady profile propagating in the NLC model at hand.

10.
Phys Rev Lett ; 96(1): 013903, 2006 Jan 13.
Article in English | MEDLINE | ID: mdl-16486455

ABSTRACT

The generation and nonlinear dynamics of multidimensional optical dissipative solitonic pulses are examined. The variational method is extended to complex dissipative systems, in order to obtain steady state solutions of the (D + 1)-dimensional complex cubic-quintic Ginzburg-Landau equation (D = 1, 2, 3). A stability criterion is established fixing a domain of dissipative parameters for stable steady state solutions. Following numerical simulations, evolution of any input pulse from this domain leads to stable dissipative solitons.

11.
Opt Express ; 14(25): 12310-5, 2006 Dec 11.
Article in English | MEDLINE | ID: mdl-19529659

ABSTRACT

The behavior of counterpropagating self-trapped optical beam structures in nematic liquid crystals is investigated. A time-dependent model for the beam propagation and the director reorientation in a nematic liquid crystal is numerically treated in three spatial dimensions and time. We find that the stable vector solitons can only exist in a narrow threshold region of control parameters. Below this region the beams diffract, above they self-focus into a series of focal spots. Spatiotemporal instabilities are observed as the input intensity, the propagation distance, and the birefringence are increased. We demonstrate undulation, filamentation, and convective dynamical instabilities of counterpropagating beams. Qualitatively similar behavior as of the copropagating beams is observed, except that it happens at lower values of control parameters.

12.
J Thromb Haemost ; 1(1): 88-94, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12871544

ABSTRACT

Plasma thrombomodulin (soluble TM; sTM) is considered to be a marker of endothelial injury, but a recent report indicated that the relationship of sTM with thrombosis is complex. Venous thromboembolic events were identified in adults in two longitudinal cohort studies, the Atherosclerosis Risk in Communities Study and the Cardiovascular Health Study, totaling 21 690 participants. After 8 years of follow-up, sTM was measured in baseline plasma of 305 participants who developed venous thrombosis and 607 who did not. Thrombomodulin A455V genotype was determined in 302 cases and 626 controls. There was no difference in the prevalence of the three TM genotypes between cases and controls and no difference in age-adjusted mean values of sTM by genotype. There were no associations of age-adjusted sTM or TMA455V genotype with overall venous thromboembolism or with thrombosis in any subtype of venous thromboembolism.


Subject(s)
Thromboembolism/blood , Thromboembolism/genetics , Thrombomodulin/blood , Thrombomodulin/genetics , Venous Thrombosis/blood , Venous Thrombosis/genetics , Age Factors , Aged , Amino Acid Substitution , Case-Control Studies , Female , Genotype , Humans , Incidence , Male , Polymorphism, Genetic , Prevalence , Prospective Studies , Risk Factors , Thromboembolism/epidemiology , Venous Thrombosis/epidemiology
13.
Phys Rev E Stat Nonlin Soft Matter Phys ; 64(5 Pt 2): 057601, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11736151

ABSTRACT

The nonlinear dynamics of laser beams carrying phase singularity in media with cubic-quintic nonlinearity changing from self-focusing to self-defocusing is examined. A novel kind of stable nonlocalized optical vortices appears in such media as well as localized vortex solitons. Linear stability analysis and numerical simulations show the stability of localized vortices only in the defocusing region.

14.
Atherosclerosis ; 157(2): 309-14, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11472730

ABSTRACT

Thrombomodulin, an endothelial membrane glycoprotein, is an essential part of the protein C anti-coagulant pathway. It may also have a role in the regulation of fibrinolysis. We carried out a cross-sectional study to assess the association of soluble thrombomodulin (sTM) with peripheral artery disease (PAD) in a stratified random sample (n=863) of otherwise healthy black and white participants of the Atherosclerosis Risk in Communities (ARIC) Study. PAD was more common in black than in white participants and associated with classical risk factors in an expected manner; positively with age, smoking, hypertension, diabetes (P=0.05), and LDL-cholesterol, and inversely with HDL-cholesterol. Significant positive associations were observed also with fibrinogen and white blood cell count. Overall, the sTM concentration was not a significant predictor of PAD. The association was, however, modified by the level of factor VIII:C in whites (P=0.002 for the interaction), but not in blacks. Protein C was inversely associated with PAD prevalence (odds ratio 0.33, 95% CI 0.18--0.61, P=0.0004). sTM was inversely associated with plasminogen, but no associations with t-PA, PAI-1, or D-dimer were seen. In conclusion, the present results provide some additional evidence on the role of thrombomodulin-protein C pathway in atherosclerotic disease and support our earlier observation on interaction between sTM and factor VIII:C.


Subject(s)
Arteriosclerosis/blood , Thrombomodulin/blood , Black or African American , Arteriosclerosis/epidemiology , Arteriosclerosis/etiology , Cohort Studies , Cross-Sectional Studies , Factor VIII/analysis , Humans , Middle Aged , Plasminogen/analysis , Prevalence , Protein C/analysis , Reference Values , Risk Factors , Solubility , United States/epidemiology , White People
15.
Ann Epidemiol ; 11(3): 166-70, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11293402

ABSTRACT

PURPOSE: The -455G/A (HaeIII) polymorphism of the beta-fibrinogen gene influences levels of plasma fibrinogen. We determined whether it influences risk of coronary heart disease. METHODS: We conducted a case-cohort study nested within a prospective investigation, the Atherosclerosis Risk in Communities Study. We accumulated 398 incident coronary heart disease cases over a median of 5.3 years of follow-up and compared their -455G/A status with a random sample of the cohort (n = 498). RESULTS: Plasma fibrinogen was higher (p = 0.04) in AA homozygous participants (341 mg/dL) than in persons carrying the G allele: GA (290 mg/dL), GG (298 mg/dL). However, there was no significant association between -455G/A and incident CHD. CONCLUSIONS: Although a small effect cannot be excluded, -455G/A does not appear to be an important genetic determinant of CHD.


Subject(s)
Arteriosclerosis/epidemiology , Coronary Disease/epidemiology , Fibrinogen/genetics , Polymorphism, Genetic , Adenine , Alleles , Arteriosclerosis/blood , Arteriosclerosis/genetics , Cohort Studies , Coronary Disease/blood , Coronary Disease/genetics , Fibrinogen/analysis , Genotype , Guanine , Humans , Incidence , Male , Middle Aged , Prospective Studies , Risk Factors , United States/epidemiology
16.
Arterioscler Thromb Vasc Biol ; 21(4): 611-7, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11304480

ABSTRACT

The fibrinolytic system may play a role in the pathogenesis of coronary heart disease (CHD), but existing prospective studies have not consistently shown an independent association between fibrinolytic factors and CHD. None has reported an association between plasminogen and CHD incidence. In the prospective Atherosclerosis Risk in Communities (ARIC) Study of middle-aged adults, we examined the association of incident CHD with several fibrinolytic factors: tissue plasminogen activator antigen, plasminogen activator inhibitor-1, plasminogen, and fibrin fragment D-dimer as well as a marker of coagulation activation (prothrombin fragment F1.2). We measured these in stored baseline plasma samples of 326 subjects who developed CHD and, for comparison, a stratified random sample of the entire cohort (n=720). Tissue plasminogen activator and plasminogen activator inhibitor-1 antigen levels were associated positively with CHD incidence in analyses adjusted for age, race, and sex but were not associated with CHD after adjustment for other risk factors. Plasminogen and D-dimer levels were associated positively and independently with CHD incidence; the multivariable-adjusted relative risks (95% CIs) for the highest versus lowest quintiles were 2.20 (1.2 to 4.2) for plasminogen and 4.21 (1.9 to 9.6) for D-dimer. F1.2 was not associated with CHD incidence. Our findings lend support for a link between fibrinolytic factors and CHD incidence. A positive association between plasminogen and CHD is seemingly opposite the direction expected but may reflect a compensatory response to impaired plasminogen activation in subjects prone to CHD.


Subject(s)
Coronary Artery Disease/blood , Fibrin Fibrinogen Degradation Products/analysis , Peptide Fragments/blood , Plasminogen Activator Inhibitor 1/blood , Plasminogen/analysis , Tissue Plasminogen Activator/blood , Biomarkers , Cohort Studies , Coronary Artery Disease/diagnosis , Coronary Artery Disease/epidemiology , Female , Fibrinolysis , Humans , Incidence , Male , Middle Aged , Prospective Studies , Prothrombin , Sampling Studies , United States/epidemiology
17.
Circulation ; 103(10): 1386-9, 2001 Mar 13.
Article in English | MEDLINE | ID: mdl-11245641

ABSTRACT

BACKGROUND: Thrombomodulin (TM) is expressed on the endothelial surface and plays an important role in vasoprotection. A common polymorphism of TM at amino acid position 455 with an alanine (A) to valine (V) transition was previously reported to be associated cross-sectionally with acute myocardial infarction. Whether this single nucleotide polymorphism predicts risk of developing coronary heart disease (CHD) is unclear. METHODS AND RESULTS: Within a large cohort study, we identified 467 incident CHD cases during an average of 5 years of follow-up. We determined TM-455 genotypes on 376 CHD cases (23% black, 77% white) and a reference sample of 461. The AA genotype was significantly more prevalent in noncases than in cases (P:=0.016). The prevalences of the AA genotype in noncase blacks and whites were 93% and 67%, respectively. The AA genotype frequency was significantly reduced in black cases versus noncases (P:=0.018). It was also lower in white cases than in noncases, but the difference was not statistically significant (P:=0.066). Weighted proportional hazards regression analysis after adjustment for age, sex, and other CHD risk factors showed that having the V allele increased risk of CHD by 6.1-fold (risk ratio 6.1, 95% CI 1.7 to 22.9) in blacks but did not significantly increase the risk in whites. CONCLUSIONS: The TM A455V polymorphism predicts risk of developing CHD in blacks.


Subject(s)
Coronary Disease/genetics , Polymorphism, Genetic , Thrombomodulin/genetics , Adult , Black People , Cohort Studies , Coronary Disease/epidemiology , Coronary Disease/ethnology , Female , Genetic Predisposition to Disease , Genetic Testing , Humans , Male , Middle Aged , Prospective Studies , Risk Factors
18.
FASEB J ; 15(2): 288-90, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11156939

ABSTRACT

The purpose of this investigation is to determine whether the levels of cyclooxygenase-2 (COX-2) expression are cell cycle dependent. We used a serum-starved human foreskin fibroblast model to determine changes in COX-2 mRNA, protein, and promoter activity in response to stimulation with interleukin-1b (IL-1b) and phorbol 12-myristate 13-acetate (PMA) at G0, G1, S and G2/M phases of the cell cycle. IL-1b (1 ng/ml) and PMA (100 nM) induced robust COX-2 expression in the G0 cells, and the level of COX-2 expression declined progressively after the cells had entered the cell cycle. The COX-2 mRNA level at G1, S and G2/M phases of the cell cycle was 76%, 46%, and 30% of that at G0, respectively. A 5-flanking promoter fragment of COX-2 constructed into a luciferase expression vector was transfected into cells. The promoter activity in response to PMA stimulation was significantly higher in G0 than in S phase cells. These results imply that G0 cells are the key players in inflammation and other COX-2-dependent pathophysiological processes. When the cells are in the proliferative phase, COX-2 inducibility becomes restrained probably by an endogenous control mechanism to avoid COX-2 mediated oxidative DNA damage.


Subject(s)
Cell Cycle/physiology , Fibroblasts/cytology , Fibroblasts/enzymology , Gene Expression Regulation, Enzymologic/physiology , Isoenzymes/genetics , Prostaglandin-Endoperoxide Synthases/genetics , Cells, Cultured , Cyclooxygenase 2 , Gene Expression Regulation, Enzymologic/drug effects , Humans , Isoenzymes/metabolism , Membrane Proteins , Models, Biological , Promoter Regions, Genetic/drug effects , Prostaglandin-Endoperoxide Synthases/metabolism , Resting Phase, Cell Cycle , S Phase , Skin/cytology , Tetradecanoylphorbol Acetate/pharmacology
19.
Circulation ; 102(16): 1901-5, 2000 Oct 17.
Article in English | MEDLINE | ID: mdl-11034936

ABSTRACT

BACKGROUND: The major platelet integrin glycoprotein IIb-IIIa plays a primary role in platelet aggregation and acute thrombus formation at the site of vascular injury. A genetic polymorphism of glycoprotein IIb-IIIa (Pl(A)) has recently been proposed as a potential genetic factor linking to platelet hyperaggregability and increased risk of myocardial infarction. Despite numerous, mostly nonprospective studies, the role of this polymorphism as a clinically relevant, inherited risk factor for coronary heart disease (CHD) is still controversial. The purpose of this study was to determine whether Pl(A2) is a risk factor for incident CHD and whether it is correlated with increased platelet activation in a case-cohort study nested within a prospective epidemiologic investigation. METHODS AND RESULTS: Blood samples were collected and processed from the Atherosclerosis Risk in Communities Study cohort at the baseline examination (1987 to 1989). They were stored at -80 degrees C. Pl(A1/A2) genotype and plasma beta-thromboglobulin levels were determined in 439 incident CHD cases and a reference cohort sample of 544 (of whom 18 were also CHD cases). The prevalence of the Pl(A2) allele was not different in cases versus noncases. No significant correlation between CHD risk factors and the Pl(A2) allele was noted either. Platelet activation, as measured by plasma beta-thromboglobulin levels, was not enhanced in individuals with the Pl(A2) allele. CONCLUSIONS: This prospective study indicates that healthy individuals carrying the Pl(A2) allele do not have an increased risk of CHD.


Subject(s)
Alleles , Antigens, Human Platelet/genetics , Coronary Disease/genetics , Antigens, Human Platelet/blood , Case-Control Studies , Cohort Studies , Coronary Disease/epidemiology , Female , Gene Frequency , Genotype , Humans , Incidence , Male , Middle Aged , Platelet Activation/genetics , Polymerase Chain Reaction , Polymorphism, Genetic , Polymorphism, Restriction Fragment Length , Prospective Studies , Regression Analysis , Risk Factors , Seroepidemiologic Studies , beta-Thromboglobulin/metabolism
20.
Arterioscler Thromb Vasc Biol ; 20(2): 601-6, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10669661

ABSTRACT

Although numerous cross-sectional studies have identified possible determinants of plasma fibrinogen and factor VII levels, few prospective studies exist. We assessed the longitudinal relation of changes in fibrinogen and factor VII over 6 years with changes to other cardiovascular risk factors in a sample of 440 men and 549 women from the Atherosclerosis Risk in Communities (ARIC) study. Fibrinogen increased more in older participants, those with or who developed diabetes, those who at any time smoked, and those whose plasma HDL cholesterol or triglycerides decreased and increased less in female participants who started hormonal replacement therapy. Factor VII coagulant activity increased more in younger participants, women, those who gained greater weight or developed diabetes, those who quit smoking, those in whom plasma triglycerides decreased, and female participants who received hormonal replacement therapy. Thus, our longitudinal data suggest with some exceptions that adverse changes in cardiovascular risk factors are accompanied by increases in plasma levels of fibrinogen and factor VII.


Subject(s)
Factor VII/analysis , Fibrinogen/analysis , Population Surveillance , Aging/blood , Arteriosclerosis/etiology , Cohort Studies , Diabetes Mellitus/blood , Female , Humans , Longitudinal Studies , Male , Middle Aged , Prospective Studies , Risk Factors , Smoking
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