Biomedical subjects

Antonija Begonja

Publications and source records attributed to Antonija Begonja.

3 recordsLinked to original sources

PubMed2004

Soluble adhesion molecules in acute ischemic stroke.

BACKGROUND: Inflammatory adhesion molecules play a key role in the development of ischemic lesions. Elevated plasma concentrations of soluble adhesion molecules are reported in stroke patients, but data are still controversial. Our aim was to explore the potential association of plasma levels of soluble (s) intercellular and vascular cellular adhesion molecules-1 (sICAM-1 and sVCAM-1), sE-selectin and sL-selectin with acute ischemic stroke. METHODS: At our university hospital in Zagreb, Croatia, we prospectively enrolled 67 subjects with acute ischemic stroke, as well as 76 consecutive healthy individuals as controls who were visiting the centre for reasons unrelated to stroke. Serum concentrations of the molecules of interest were determined by means of quantitative sandwich enzyme immunoassay. RESULTS: Mean levels of sICAM-1 (p < 0.001), sVCAM-1 (p < 0.034) and sE-selectin (p < 0.002) were higher in patients than in controls, whereas sL-selectin was lower in patients (p = 0.043). In patients, levels of soluble adhesion molecules were independent of age and sex except for sL-selectin, which was inversely correlated with age (r = -0.260, p = 0.034) and higher in women (p = 0.006) and diabetics (n = 14; p = 0.004). Serum levels did not differ significantly with respect to carotid atherosclerotic disease, smoking status, hypertension or hypercholesterolemia. As well as correlating with each other, concentrations of soluble adhesion molecules in patients correlated with traditional biochemical markers of inflammation: total leukocyte count, erythrocyte sedimentation rate (ESR) and C-reactive protein level. Concentrations of sICAM-1 and high-density lipoprotein-cholesterol and ESR were identified as significant independent predictors/indicators of acute ischemic stroke. CONCLUSIONS: Acute ischemic stroke is associated with elevated plasma levels of sICAM-1, sVCAM-1 and sE-selectin, independent of age, sex and other recognized risk factors for stroke. Decreased levels of sL-selectin are associated with acute stroke. The observed changes in serum concentrations of adhesion molecules indicate inflammatory process occurring during acute cerebral ischemia.

Aged↗

PubMed2003

Potent inhibition of human platelets by cGMP analogs independent of cGMP-dependent protein kinase.

Platelets play a key role in hemostasis through their ability to rapidly adhere to activated or injured endothelium, subendothelial matrix proteins, and other activated platelets. A strong equilibrium between activating and inhibiting processes is essential for normal platelet and vascular function, impairment of this equilibrium being associated with either thrombophilic or bleeding disorders. Both cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP) have been established as crucial and synergistic intracellular messengers that mediate the effects of platelet inhibitors such as nitric oxide (NO) and prostacyclin (PG-I2). However, it was recently suggested that a rapid cGMP/cGMP-dependent protein kinase (cGK)-mediated extracellular signal-related kinase (ERK) phosphorylation promotes platelet activation. This hypothesis was examined here by evaluating established and proposed cGK activators/inhibitors with respect to their capacity to promote either platelet activation or inhibition. In particular, the regulatory role of cGK for ERK phosphorylation and thrombin-, thromboxane-, and VWF-induced platelet activation was investigated. The data obtained do not support the concept that cGK-mediated ERK phosphorylation promotes platelet activation but confirm the inhibitory role of cGK in platelet function. One explanation for these discrepancies is the novel finding that extracellular cGMP analogs potently and rapidly inhibit thrombin-, thromboxane-, and VWF-induced human platelet signaling and activation by a cGK-independent mechanism.

8-Bromo Cyclic Adenosine Monophosphate↗

PubMed2003

Croatian population data for the C677T polymorphism in methylenetetrahydrofolate reductase: frequencies in healthy and atherosclerotic study groups.

BACKGROUND: The aim of this study was to investigate the frequency of C677T methylenetetrahydrofolate reductase (MTHFR) mutation in healthy Croatian volunteers and in patients with atherosclerosis. METHODS: The C677T MTHFR gene mutation was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 640 subjects, residents of the Zagreb city or Zagreb surroundings. Control group (n=298) was healthy blood donors. Patients (n=342) were divided into two groups of those with coronary heart disease, CAD (n=247) and those with >60% carotid stenosis, CS (n=95). RESULTS: CC genotype was recorded in 45% of healthy volunteers and 46% of patients (46.3% with CS and 46.2% with CAD). TC genotype was found in 49% of healthy volunteers and 45% of patients (46.3% with CS and 44.9% with CAD). There was no significant difference (p>0.05) from the control group in the genotype or allele frequency either for the overall group of patients with atherosclerosis or for the patient subgroups. CONCLUSION: The preliminary study of MTHFR polymorphism in control subjects and cardiovascular disease/carotid stenosis patients revealed that in Croats there was a low frequency of TT genotype (6% in controls vs. 9% in patients) and T allele (31% for cases and controls). Additionally, our results did not show significantly higher frequency of MTHFR mutation in CAD and CS studied groups.

Adult↗