Effects of fibrates on plasma prothrombotic activity in patients with type IIb dyslipidemia

OBJECTIVE

Increased levels of fibrinogen and plasminogen activator inhibitor 1 (PAI-1) are associated with an increased risk of ischemic coronary disease and its complications. Since atherogenic dyslipidemias are well-known risk factors for coronary heart disease, this study aimed to determine whether Type IIb dyslipidemia, one of the most atherogenic dyslipidemias, is accompanied by increased PAI-1 and fibrinogen synthesis. The additional aim of this study was to evaluate the effect of micronized fibrates on the levels of PAI-1 and fibrinogen in patients with Type IIb dyslipidemia.

SUBJECTS

Thirty patients with Type IIb dyslipidemia and 12 age-matched control subjects were studied. Fourteen patients were treated with fenofibrate and 16 were treated with ciprofibrate for 1 month.

METHODS

Plasma PAI-1 levels were measured by the ELISA method with Diagnostica Stago kit. The level of fibrinogen was measured by the Clauss method.

RESULTS

PAI-1 levels in dyslipidemic patients before treatment differed significantly in both the fenofibrate and ciprofibrate treatment groups (101.18 +/- 36.47 ng/ml, 87.64 +/- 32.06 ng/ml, respectively) from those in the control group (32.32 +/- 7.39 ng/ml, p < 0.001). Compared with the control subjects (2.91 +/- 0.35 g/l), fibrinogen levels before treatment were higher in patients with dyslipidemia treated with ciprofibrate (3.42 +/- 0.59 g/l, NS) and fenofibrate (3.65 +/- 1.10 g/l, p < 0.05). One-month ciprofibrate treatment resulted in an insignificant decrease in PAI-1 levels (76.28 21.60 ng/ml, NS) and in a significant decrease in fibrinogen levels (2.73 +/- 0.40 g/l, p < 0.01). After one-month fenofibrate treatment PAI-1 levels (81.22 +/- 25.01 ng/ml, p < 0.01) and fibrinogen levels (2.95 0.72 g/l, p < 0.01) decreased significantly.

CONCLUSION

Type IIb dyslipidemic patients have increased levels of PAI-1 and fibrinogen. Micronized fibrates decreased not only lipid levels but also the levels of fibrinogen and PAI-1 in these patients.

Reliability and responsiveness of three different pain assessments

The visual analogue scale (VAS) and ordered categorical scales, i.e. numeric rating scales (NRS), are commonly used in the assessment of pain. However, these scales are bounded by fixed endpoints and thus the range of measurement is limited. The disparity in repeated assessments of perceived pain intensity with the VAS, NRS, and electrical stimulation applied as a matching stimulus was studied in 69 patients (48 women and 21 men, 19-72 years) with chronic nociceptive or neurogenic pain. Responsiveness with transcutaneous electrical nerve stimulation (TENS) using the same measurement procedures was evaluated in the same patients. Comparison of results from the three pain assessments showed that the painmatcher is at least as reliable and responsive as VAS and NRS. None of the three measurements showed evidence for systematic disagreement and had only significant random individual disagreement. They also showed evidence for responsiveness.

[Estimation of plasma malonyl dialdehyde concentration in patients with pulmonary tuberculosis]

Plasma malonyl dialdehyde (MDA) concentration was determined by Placer method in patients with pulmonary tuberculosis before and during treatment period with tuberculostatic drugs. Patients were divided into three groups. Group I comprised 20 patients (10 men and 10 women) aged 24-74 years (mean 48.3 years) with pulmonary tuberculosis BK(+). Group II comprised 20 patients (15 men and 5 women) aged 19-67 years (mean 45.1 years) with pulmonary tuberculosis BK(0). The control group consisted of 16 clinically healthy persons (12 men and 4 women) aged 28-59 years (mean 42.5 years). In patients blood samples (5 ml) were collected for examination from cubital vein before, after 1-month and 2-month treatment period with tuberculostatic drugs. In the control group blood samples were collected from cubital vein once. Results of our study showed that plasma MDA concentrations in patients with pulmonary tuberculosis, both before and during treatment period with tuberculostatic drugs, were significantly higher, in comparison to the control group.

[Generation of reactive oxygen species by peripheral blood neutrophils in patients with pulmonary tuberculosis]

Oxygen metabolism of neutrophils was measured using chemiluminescence method in patient with pulmonary tuberculosis. Patients were included into three groups. Group I--20 patients (10 men, 10 women) aged 24-74 years (mean 48.3 years) with pulmonary tuberculosis BK(+). Group II--20 patients (15 men, 5 women) aged 19-67 years (mean 45.1 years) with pulmonary tuberculosis BK(0). The control group consisted 16 clinically healthy persons (12 men, 4 women) aged 28-59 years (mean 42.5 years). Blood samples (5 ml) were collected for examination from cubital vein early morning before breakfast. A luminometer 1251 coupled with an IBM PC AT compatible computer was used for the measurement of chemiluminescence. The chemiluminescence of non-stimulated neutrophils and those stimulated by a receptor stimulus formyl-Met-Leu-Phe (fMLP) as well as an extrareceptor stimulus phorbol myristate acete (PMA) was measured. The results of our study demonstrated that chemiluminescence of non-stimulated as well as stimulated by fMLP and PMA neutrophils was lower in comparison to the values of chemiluminescence in the control group.

A non-parametric approach to translating gene region heterogeneity associated with phenotype into location heterogeneity

MOTIVATION

The analysis of genetic data poses statistical problems in the form of high dimensionality with small sample sizes. The construction of a composite gene region (sequence pair) heterogeneity measure is one technique for reducing the dimensionality of the problem. This approach however is not without cost, since the contribution of locations to observed gene region differences between groups becomes entangled in this summary measure. This is problematic since it is of scientific interest to identify locations that together depict phenotype.

RESULTS

A method is proposed for relating observed gene region heterogeneity back to the location level. In the spirit of a factor analysis-type setting, the approach focuses on identifying a latent variable structure among locations to explain within and between group genetic differences associated with phenotype. The method is flexible for identifying either the additive contribution from individual locations or the additive contribution from a group of locations, to observed gene region heterogeneity, depending upon the weighting scheme used in constructing a gene region heterogeneity measure. The approach is illustrated with clinical trial data, where the problem of altered HIV drug susceptibility is examined through characterizing location contributions to HIV protease gene region differences associated with a phenotypic treatment response.

AVAILABILITY

The Splus (MathSoft, Inc. S-Plus 2000, Seattle, WA, 1999) developed menu-driven functions for obtaining results, GENE_ S (J.Kowalski, Harvard School of Public Health, Boston, MA 2001), is available from the author upon request.

Correlation between left ventricular mass and the resting and post-exercise release of ANP in healthy men

BACKGROUND

The goal of our study was to assess the impact of left ventricular mass on the resting and post-exercise release of atrial natriuretic peptide (ANP) in healthy young men.

MATERIAL AND METHODS

The study involved 36 young men divided into two groups. Group I consisted of 18 healthy untrained men 20-24 years old (mean 22.1). Group II included 18 healthy men aged 22-27 years (mean 23.4 years) who had been taking regular dynamic and static physical exercise for at least 2 years. Echocardiograms were performed in both groups. The thickness of the posterior wall (PW-d), the thickness of the interventricular septum (IV-d), and the left ventricular end-diastole dimension (DdLV) were measured and used to calculate the left ventricular mass. Subsequently, all the patients underwent an exercise test on a cycloergometer. The workload in both groups was 2 Watts/kg at 60 rpm. The anticipated age-adjusted heart rate values at this workload were 170/min in Group I and 155/min in Group II. Blood samples were collected before the exercise test and 1 minute afterwards. The concentrations of ANP and sodium ions and the hematocrit index were measured.

RESULTS

In Group I the mean left ventricular mass was 193.1 +/- 51.8 g; in Group II, 248.1 x 91.91 g, which is a statistically significant difference. The resting ANP concentration in Group I was higher than in Group II (24.44 +/- 12.35 pg/ml vs 21.39 +/- 11.03 pg/ml), but the difference was not statistically significant. After exercise there was a significant increase in ANP concentration in both groups: 53.89 +/- 39.98 pg/ml and 47.50 +/- 26.67 pg/ml respectively. There was no correlation between the ANP concentration before and after exercise and the left ventricular mass in either group. There were also no differences between the two groups in resting hematocrit: 48% in Group I and 49.5% in Group II. A significant increase in hematocrit was observed in both groups after exercise. Exertion induced a significant decrease in the plasma sodium concentration in both groups. The ratio of mean plasma ANP concentration at rest to left ventricular mass, corrected according to hematocrit values, was 6.10 in Group I and 4.25 in Group II; after exercise, 14.06 and 9.72 respectively. The ratio of post-exercise increase in ANP concentration to left ventricular mass was 7.6 in Group I and 5.32 in Group II. The average left ventricular mass in Group II, although 30% greater than in Group I, did not exceed 259 g, which is considered the upper limit of normal. Despite this difference the ANP concentration in Group II was ca. 20% lower than in Group II, without cardiac hypertrophy. In both groups a significant increase in ANP concentration was observed when the subjects were exposed to submaximal workload. In Group II, however, the increase was markedly lower. No correlation was found between left ventricular mass at rest and post-exercise ANP release, nor between left ventricular mass and ANP secretion. By contrast, a tendency towards lower ANP release was found in Group II, despite the markedly larger left ventricular mass.

CONCLUSIONS

In the evaluation of risk related to left ventricular hypertrophy, both the mass index and cardiac functional efficiency should be taken into account.

Identification of an angiogenic mitogen selective for endocrine gland endothelium

The known endothelial mitogens stimulate growth of vascular endothelial cells without regard to their tissue of origin. Here we report a growth factor that is expressed largely in one type of tissue and acts selectively on one type of endothelium. This molecule, called endocrine-gland-derived vascular endothelial growth factor (EG-VEGF), induced proliferation, migration and fenestration (the formation of membrane discontinuities) in capillary endothelial cells derived from endocrine glands. However, EG-VEGF had little or no effect on a variety of other endothelial and non-endothelial cell types tested. Similar to VEGF, EG-VEGF possesses a HIF-1 binding site, and its expression is induced by hypoxia. Both EG-VEGF and VEGF resulted in extensive angiogenesis and cyst formation when delivered in the ovary. However, unlike VEGF, EG-VEGF failed to promote angiogenesis in the cornea or skeletal muscle. Expression of human EG-VEGF messenger RNA is restricted to the steroidogenic glands, ovary, testis, adrenal and placenta and is often complementary to the expression of VEGF, suggesting that these molecules function in a coordinated manner. EG-VEGF is an example of a class of highly specific mitogens that act to regulate proliferation and differentiation of the vascular endothelium in a tissue-specific manner.

Neuroleptics normalize increased release of interleukin- 1 beta and tumor necrosis factor-alpha from monocytes in schizophrenia

Some recent reports show that schizophrenia is accompanied by changes in lymphocyte activity. This study investigated the activity of monocytes by determining their release of interleukin- 1 beta (IL- 1 beta) and tumor necrosis factor-alpha (TNF-alpha). Monocytes were immunomagnetically isolated from the peripheral blood of schizophrenic patients before and after neuroleptic medication and stimulated by lipopolisaccharide (LPS) in vitro. The monocytes of schizophrenic patients released significantly higher amounts of IL- 1 beta and TNF-alpha than those of healthy controls. Treatment with the typical neuroleptics haloperidol and perazine decreased the release of IL- 1 beta and TNF-alpha to the control levels. The study has shown that the activity of monocytes is increased in schizophrenia and that neuroleptic treatment normalizes this activity.

Increasing protein stability using a rational approach combining sequence homology and structural alignment: Stabilizing the WW domain

This study shows that a combination of sequence homology and structural information can be used to increase the stability of the WW domain by 2.5 kcal mol(-1) and increase the T(m) by 28 degrees C. Previous homology-based protein design efforts typically investigate positions with low sequence identity, whereas this study focuses on semi-conserved core residues and proximal residues, exploring their role(s) in mediating stabilizing interactions on the basis of structural considerations. The A20R and L30Y mutations allow increased hydrophobic interactions because of complimentary surfaces and an electrostatic interaction with a third residue adjacent to the ligand-binding hydrophobic cluster, increasing stability significantly beyond what additivity would predict for the single mutations. The D34T mutation situated in a pi-turn possibly disengages Asn31, allowing it to make up to three hydrogen bonds with the backbone in strand 1 and loop 2. The synergistic mutations A20R/L30Y in combination with the remotely located mutation D34T add together to create a hYap WW domain that is significantly more stable than any of the protein structures on which the design was based (Pin and FBP28 WW domains).

PET imaging of somatostatin receptors using [68GA]DOTA-D-Phe1-Tyr3-octreotide: first results in patients with meningiomas

Imaging of somatostatin receptors (SSTRs) using [111In]diethylenetriaminepentaacetic-acid-octreotide (DTPAOC) has proven to be helpful in the differentiation of meningiomas, neurinomas or neurofibromas, and metastases as well as in the follow-up of meningiomas. A drawback of the SPECT method is its limited sensitivity in detecting small meningiomas. Because of PET's increased spatial resolution and its ability to absolutely quantify biodistribution, a PET tracer for SSTR imaging would be desirable.

METHODS

1,4,7,10-tetraazacyclododecane-N,N',N",N"'-tetraacetic-acid-D-Phe1-Tyr3-octreotide (DOTATOC) was labeled using the positron-emitting generator nuclide 68Ga. We acquired dynamic PET images over 120 min after intravenous injection of 175 MBq [68Ga]DOTATOC in 3 patients suffering from 8 meningiomas (WHO I degrees; 7- to 25-mm diameter). Patients' heads had been fixed using individually shaped fiber masks equipped with an external stereotactic localizer system to match PET, CT, and MRI datasets.

RESULTS

[68Ga]DOTATOC was rapidly cleared from the blood (half-life alpha, 3.5 min; half-life beta, 63 min). Standardized uptake values (SUVs) of meningiomas increased immediately after injection and reached a plateau 60-120 min after injection (mean SUV, 10.6). No tracer could be found in the surrounding healthy brain tissue. All meningiomas (even the 3 smallest [7- to 8-mm diameter]) showed high tracer uptake and could be visualized clearly. Tracer boundaries showed a good correspondence with the matched CT and MRI images. PET provided valuable additional information regarding the extent of meningiomas located beneath osseous structures, especially at the base of the skull.

CONCLUSION

According to our initial experiences, [68Ga]DOTATOC seems to be a very promising new PET tracer for imaging SSTRs even in small meningiomas, offering excellent imaging properties and a very high tumor-to-background ratio.

[Comparison of HLA class I and DR class II antigen frequency in Polish patients, in relation to different stages of the disease]

The aim of this study was to analyze the association between HLA class I and class II DR frequency in the different stages of sarcoidosis in Polish population. 88 patients and 30 healthy controls have been typed. Patients were divided into three groups depending on radiological findings. In the first group were 28 cases presenting the regression of the disease. In the second were 33 patients in stable stage II or III and in the third group 27 patients with pulmonary fibrosis (stage IV). The typing was performed by NIH method using commercial sera. There were no statistically significant differences between studied group in HLA-A class I. The frequency of HLA B-18 was statistically more frequent in patients with sarcoidosis compared to healthy controls. HLA-DR1 was not present in third group of patients and the difference was significant compared to healthy controls.

[Evaluation of anti-mycobacterial antibody IgG concentration in rapid diagnosis of tuberculosis]

Tuberculosis is not always easy to diagnose. All the methods applied in diagnosis of this illness have certain limitations. In this study the value of Rapid Test TB in diagnosis of tuberculosis was evaluated. The aim of the test is to detect antibody against mycobacterial antigen 38 kDa. Material consisted of 100 persons divided into 4 groups: BK(+) tuberculosis patients, BK (0) tuberculosis patients--culture (+), lung cancer patients and patients with sarcoidosis. Positive results were obtained in 100% of culture positive patients and in 10% of patients culture (+), in 20% of lung cancer patients and in 40% of patients with sarcoidosis. Specifity of the test was 55%. The results indicate that Immunozyme Mycobacterium test is valuable tool in tuberculosis diagnosis especially in case when a technical equipment is wanting.

Development of poly-(D,L-lactide--coglycolide) microsphere formulations containing recombinant human vascular endothelial growth factor to promote local angiogenesis

Although preclinical animal studies have demonstrated the utility of recombinant human vascular endothelial growth factor (rhVEGF) in promoting neovascularization in regions of ischemia, rhVEGF systemic administration did not provide clinical benefit to patients in recent placebo-controlled Phase II clinical trials. The amount of rhVEGF localized in the ischemic region after systemic administration is minimal and does not persist for more than 1 day. A greater persistence of rhVEGF at the region of ischemia may provide an increased angiogenesis with the eventual formation of patent blood vessels to restore nourishment to the tissues. We sought to develop a formulation of rhVEGF in poly(D,L-lactide--co-glycolide) (PLG) microspheres that would provide a continuous local delivery of intact protein. A stable formulation of rhVEGF for encapsulation contained a small amount of a stabilizing sugar, trehalose. Addition of excess trehalose increased the rate of release from the PLG. In addition, PLG with free acid end groups appeared to retard the initial release of rhVEGF by associating with it through ionic interactions at the positively charged heparin binding domain. rhVEGF was released continuously for 21 days with a very low (less than 10%) initial burst. The released rhVEGF aggregated and hydrolyzed over time and lost heparin affinity but not receptor affinity. The compression molding of rhVEGF PLG microspheres into disks yielded formulations with a low initial release and a lag of 10 days followed by complete release. The PLG microsphere formulations were assessed in the corneal implant model of angiogenesis and generated a dose-dependent angiogenic response. These formulations were also administered intravitreally and subretinally, generating local neovascularization comparable to the human disease states, vitroretinopathy and age-related macular degeneration, respectively. The rhVEGF PLG formulations may increase local angiogenesis without systemic side effects and may also be useful in the development of ocular disease models.

A comparative meta-analysis on the variability in test performance among FDA-licensed enzyme immunosorbent assays for HIV antibody testing

BACKGROUND

Although independently published studies have compared diagnostic test performance among various manufactured enzyme immunosorbent assays (EIAs) used in HIV antibody testing, none have attempted to formally synthesize such results through a comparative meta-analysis. In particular, no estimates of post-FDA approval test performance, in terms of sensitivity and specificity, and their associated variability within each manufacturer, has been reported in the literature, along with an analysis of the relative differences in manufacturer test performance in practice (after FDA approval).

METHODS

Retrieval of studies was done using several searching strategies, while retrieval of manufacturer information was done through package inserts and direct contacts. Comparisons of HIV antibody test performance across manufacturers and within a single manufacturer were made based on 16 estimates (from 11 articles) and 33 estimates (from 19 articles), respectively. A generalized linear model, based upon Bayes estimates of sensitivity and specificity, was used to assess the impact of several study-level covariates on the performance of these EIAs, with overall estimates of manufacturer test performance and associated variability obtained based on generalized estimating equations.

RESULTS

Estimates of test performance were obtained across studies, with a significant (P < 0.01) difference between manufacturers. The test performance of each manufacturer significantly interacted (P < 0.05) with the following study-level covariates: type of population screened, year of diagnostic testing and study quality. Among a single manufacturer, Abbott, significant improvement in estimates of test sensitivity (P < 0.01) and specificity (P < 0.01) was observed with each newly produced antibody kit.

CONCLUSION

Estimates on the relative differences in test performance within each manufacturer may be used for guiding decisions on the choice of EIA test kit for HIV antibodies, given the type of population screened, as well as cost and time considerations. In addition, the results of this meta-analysis may be used in modeling HIV prevalence when used as prior information within a Bayesian framework or for standardizing test results among various manufacturers.

Hepatocyte growth factor enhances vascular endothelial growth factor-induced angiogenesis in vitro and in vivo

Vascular endothelial growth factor (VEGF) is an important mediator of angiogenesis in both physiological and pathological processes. Hepatocyte growth factor (HGF) is a mesenchyme-derived mitogen that also stimulates cell migration, and branching and/or tubular morphogenesis of epithelial and endothelial cells. In the present study, we tested the hypothesis that simultaneous administration of HGF and VEGF would synergistically promote new blood vessel formation. HGF acted in concert with VEGF to promote human endothelial cell survival and tubulogenesis in 3-D type I collagen gels, a response that did not occur with either growth factor alone. The synergistic effects of VEGF and HGF on endothelial survival correlated with greatly augmented mRNA levels for the anti-apoptotic genes Bcl-2 and A1. Co-culture experiments with human neonatal dermal fibroblasts and human umbilical vein endothelial cells demonstrated that neonatal dermal fibroblasts, in combination with VEGF, stimulated human umbilical vein endothelial cells tubulogenesis through the paracrine secretion of HGF. Finally, in vivo experiments demonstrated that the combination of HGF and VEGF increased neovascularization in the rat corneal assay greater than either growth factor alone. We suggest that combination therapy using HGF and VEGF co-administration may provide a more effective strategy to achieve therapeutic angiogenesis.

A new immunological marker of atherosclerotic injury of arterial wall

BACKGROUND AND OBJECTIVE

The atherosclerotic arterial injuries lead to many life threatening vascular incidents. It has been well documented that inflammatory processes play an important role in atherogenesis. Intensive studies are undertaken to find a serum marker of inflammatory reaction correlated with arterial injuries.

METHODS

In our study we measured the level of interleukin-6 (IL-6) in patients with dyslipidemia IIa and IIb biochemically confirmed. Control estimations were done in age-matched group. Arterial injuries were evaluated as a thickening of complex intima-media in common carotid arteries by means of Doppler ultrasonography.

RESULTS

Levels of IL-6 were significantly higher in both groups of patients with dyslipidemia as compared with the healthy control persons (IIa vs control p<0.001, IIb vs control p<0.001). The plasma level of IL-6 is significantly correlated to intima-media complex thickness (r=0.68, p<0.0001).

CONCLUSION

We conclude that increase of serum concentration of IL-6 may be related to arterial wall injuries in the course of the most atherogenic lipid disorders.

[Respiratory response to inspiratory resistive load changes in patients with obstructive sleep apnea syndrome]

Patients with OSA have many episodes of increased airway resistance because of repeated collapses of upper airways during night. The aim of this work was to evaluate respiratory response during chemical stimulation without and with added inspiratory resistive load (10 cmH2O/L/sec). The studies were performed during quiet breathing with air and during hypercapnic and hypoxic rebreathing tests without and with inspiratory resistive loading in 23 obese (BMI = 34.4 +/- 4.3 kg/m2) patients with OSA and in 10 healthy subjects with similar weight (BMI = 32.4 +/- 4.3 kg/m2). The measurements of respiratory responses (ventilation, mouth occlusion pressure) were performed with the use of computerized equipment. During quiet breathing in response to added load an increase of P0.1 in controls and in OSA patients was observed. During hypercapnic stimulation the ventilatory response with additional load decreased in patients as well as in controls. The slope of mouth occlusion pressure response increased significantly in controls (from 4.40 to 6.83 cmH2O/kPa, p < 0.001) and slightly weaker in OSA patients (from 4.21 to 5.43 cmH2O/kPa, p < 0.05). Although the difference between the slopes was not significant, we found that the absolute increase of P0.1 measured at point 8 kPa of PEtCO2 during loaded breathing was significantly smaller in OSA patients in comparison to controls. (2.1 vs. 10.3 cm H2O; p < 0.001). During hypoxic stimulation occlusion pressure responses were similar in both examined groups. In conclusion we postulate that OSA patients have impaired respiratory compensation of additional inspiratory load, what was demonstrated during hypercapnic rebreathing test.

Stressful life events, bipolar disorder, and the "kindling model"

A common misconception is that bipolar disorder is an endogenous process. However, previous research suggests a role for life events in the onset of and recovery from bipolar episodes. Yet, there remains some question as to whether the relationship between life events and onset changes over the course of the disorder as a result of the number of episodes an individual has experienced. Using a rigorous interview measure of stressful life events, the current study tested the kindling model (R. M. Post, 1992), which theorizes that major life events play a diminishing role over the course of illness in bipolar patients. Analyses revealed that the number of episodes experienced does not appear to have a significant effect on bipolar 1 patients' reactivity to external stressors. In addition, the results suggest that a more complex relationship exists among age, stress, and onset of new episodes than can be adequately explained by the kindling model.

Analysis of biological effects and signaling properties of Flt-1 (VEGFR-1) and KDR (VEGFR-2). A reassessment using novel receptor-specific vascular endothelial growth factor mutants

Endothelial cells express two related vascular endothelial growth factor (VEGF) receptor tyrosine kinases, KDR (kinase-insert domain containing receptor, or VEGFR-2) and Flt-1 (fms-like tyrosine kinase, or VEGFR-1). Although considerable experimental evidence links KDR activation to endothelial cell mitogenesis, there is still significant uncertainty concerning the role of individual VEGF receptors for other biological effects such as vascular permeability. VEGF mutants that bind to either KDR or Flt-1 with high selectivity were used to determine which of the two receptors serves to mediate different VEGF functions. In addition to mediating mitogenic signaling, selective KDR activation was sufficient for the activation of intracellular signaling pathways implicated in cell migration. KDR stimulation caused tyrosine phosphorylation of both phosphatidylinositol 3-kinase and phospholipase Cgamma in primary endothelial cells and stimulated cell migration. KDR-selective VEGF was also able to induce angiogenesis in the rat cornea to an extent indistinguishable from wild type VEGF. We also demonstrate that KDR, but not Flt-1, stimulation is responsible for the induction of vascular permeability by VEGF.

Levels of sICAM-1, sVCAM-1 and MCP-1 in patients with hyperlipoproteinemia IIa and -IIb

OBJECTIVE

Hyperlipoproteinemia is one of the factors that are involved in the development of atherosclerosis. One of the mechanisms through which these high plasma lipid levels trigger the formation of atherosclerotic lesions is a change in the expression of adhesion molecules on endothelial and smooth muscle cells. The aim of this study was to evaluate the plasma levels of soluble intracellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1) and monocyte chemoattractant protein-1 (MCP-1) in patients with Type IIa (HLP-IIa) and IIb (HLP-IIb) hyperlipoproteinemias.

SUBJECTS

Twenty patients with HLP-IIa, 20 patients with HLP-IIb and 23 control subjects were studied. To accurately evaluate adhesion molecule levels, we excluded those hyperlipemic patients and control subjects who had an inflammatory disease.

METHODS

Plasma sICAM-1, sVCAM-1 and MCP-1 levels were measured by the ELISA method.

RESULTS

sVCAM-1 levels in HLP-IIa and HLP-IIb patients (535 +/- 27 ng/ml and 545 +/- 22 ng/ml, respectively) did not differ significantly from those in the control group (558 +/- 20 ng/ml). sICAM-1 levels were significantly higher in patients with HLP-IIa and HLP-IIb (279 +/- 10 ng/ml and 322 +/- 12 ng/ml, respectively) compared to the control group (226 +/- 10 ng/ml). MCP-1 levels were significantly higher in HLP-IIa and HLP-IIb patients (151 +/- 12 pg/ml vs 154 +/- 12 pg/ml, respectively) compared to healthy controls (98 +/- 4 pg/ml). sICAM-1 levels in the HLP-IIb group were significantly higher than in the HLP-IIa group.

CONCLUSION

The results of the study suggest that lipid abnormalities affect the levels of adhesion molecules and chemokines in plasma.