Vascular Endothelial Growth Factor and Nitric Oxide Serum Levels in Arterial Hypertension

Vascular endothelial growth factor (VEGF) is a specific mitogen for endothelial cells and an inducer of the angiogenic procedure. Endothelial nitric oxide (NO) is a potent vasodilator. Because both are implicated in vascular function, it is possible that they would be significantly affected in arterial hypertension. The aim of the study was the investigation of the levels of the two substances in blood serum and their potential relation in patients with untreated essential arterial hypertension compared to healthy individuals. VEGF levels were found 129.1 +/- 135.9 pg/mL in a group of 28 untreated hypertensive patients vs. 209.0 +/- 133.3 pg/mL in a group of 28 healthy individuals (p = 0.008). Nitrites and nitrates levels (as an indirect index of calculating NO levels) were also lower in hypertensive patients than in healthy individuals (19.8 +/- 9.7 micromol/L vs. 29.6 +/- 15.9 micromol/L, p = 0.014). A positive correlation between NOx (nitrites and nitrates levels) and VEGF was found in healthy individuals (r = 0.55, p = 0.003), but there was no correlation in hypertensive patients. The significant decrease of serum VEGF and NO in arterial hypertension and the existence of a correlation between the two substances in healthy subjects that did not exist in the hypertensive patients are findings that need evaluation.

Effect of zoledronic acid on markers of bone turnover and mineral density in osteoporotic patients with beta-thalassaemia

Osteoporosis has emerged as an important cause of morbidity in patients with thalassemia major. Studies regarding the efficacy of bisphosphonates in thalassemia-induced osteoporosis have yielded conflicting results. We performed this prospective study to evaluate the efficacy of zoledronic acid in osteoporotic patients with thalassemia major. Patients, 29, were given 1 mg zoledronic acid intravenously every 3 months for a total of four doses. Twenty age- and sex-matched healthy blood donors served as controls. Before each infusion and 3 months after the last infusion, we determined serum levels of osteoprotegerin (OPG), N-terminal cross-linking telopeptide of type I collagen (NTX), osteocalcin (OC) and insulin-like growth factor 1 (IGF-1). Bone mineral density (BMD) of the lumbar spine was measured at baseline and after the treatment's completion. At baseline, OPG did not differ significantly between patients and controls (p=0.2), NTX were higher in patients although not significantly (p=0.139), whereas, OC levels were significantly higher and IGF-1 levels significantly lower in patients than in controls (p<0.001 and p<0.006, respectively). Zoledronic acid administration resulted in a significant decrease in NTX, OC and IGF-1 (p<0.05, p<0.001 and p<0.05, respectively) and in a significant increase in OPG and BMD (p<0.05 for both comparisons). The change in NTX, osteocalcin and IGF-1 became significant as early as 3 months after the first administration of zoledronic acid, while the change in OPG reached significance only after three infusions. Our study supports the effectiveness of bisphosphonates in the treatment of thalassemia-induced osteoporosis.

Acute large bowel pseudo-obstruction due to multiple myeloma

Involvement of the gastrointestinal (GI) tract by multiple myeloma (MM) is extremely rare. The small intestine and stomach are the most frequent sites of spread. We report 1 case of a 61-year-old woman who presented with clinical and radiographic features of an acute large bowel pseudo-obstruction. An abdominal computerized tomography (CT) showed a large tumor of the rectum. On morphological and immunohistochemical examination the tumor fulfilled the criteria of MM. The patient received combined chemotherapy and radiotherapy which led to the disappearance of the tumor. A review of the literature revealed that this is the first reported case of MM presented as acute large bowel pseudo-obstruction due to a rectal myeloma tumor.

Elevated levels of serum vascular endothelial growth factor in patients with polycythaemia vera

Angiogenesis seems to be a prominent event of myeloproliferative diseases. There are few reported data on angiogenesis and the significance of its stimulator, the vascular endothelial growth factor (VEGF), in polycythaemia vera (PV). We report our observation of elevated serum VEGF levels in patients suffering from PV. Twenty patients with PV and 20 age-matched healthy subjects were enrolled. VEGF levels were measured by a quantitative sandwich enzyme immunoassay. Serum VEGF levels in PV were found to be very significantly higher than in healthy individuals (569.7 +/- 101.2 vs. 164.7 +/- 32.8 pg/ml, p = 0.001). We found no correlation between VEGF and haemoglobin, platelet or leucocyte counts in the patient group. Different therapeutic regimens had no influence on VEGF levels. However, in the control group, we observed a positive correlation between VEGF levels and platelet counts (r = 0.52, p = 0.02). Platelet counts did not differ between patients and healthy subjects. We also evaluated platelet-poor plasma VEGF levels in 10 patients and in all healthy individuals. We found very low levels of VEGF, approximately zero in most cases, in both groups and there was obviously no difference between the two groups. Our results indicate that VEGF is overproduced in PV. However, follow-up studies are needed to verify the role of this factor.

Cyclosporine and its metabolites before and 2 h post-dose: comparative measurements of a monoclonal and a polyclonal immunoassay

The aim of the study was to investigate the better accuracy of the 2-h post-dose (C2) levels of cyclosporine (CyA), compared with the pre-dose (C0) levels and to evaluate the results measured by a monoclonal or a polyclonal immunoassay. The parent compound of CyA in C2 (monoclonal2) was measured in 53 kidney transplant patients by the monoclonal fluorescence polarization method, as well as the parent compound plus metabolites (polyclonal2) by the polyclonal fluorescence polarization method. Also, the parent compound was measured in 21 of the patients for the C0 (monoclonal0), whereas the parent compound plus metabolites in 36, for the C0 (polyclonal0). As level of metabolites was considered the difference between polyclonal and monoclonal values (polyclonal-monoclonal), either in C0 (metabolites0) or in C2 (metabolites2). The ratio polyclonal2/monoclonal2 gave a mean value of 1.7+/-0.2 (mean+/-SD), whereas the mean value of the ratio polyclonal0/monoclonal0 was 2.3+/-0.6, with almost double variation. The mean value of the ratio metabolites2/monoclonal2 was 0.7+/-0.2 and of the ratio metabolites0/monoclonal0 was 1.3+/-0.6. The difference between the two ratios is very significant (p = 0.000001) and they are not correlated with each other (r = 0.18, p = 0.44). The measurements of monoclonal0 and polyclonal0 or monoclonal2 and polyclonal2 are very significantly correlated (r = 0.94, p = 0.000001 and r = 0.97, p = 0.000001, respectively). In C0 the proportion of metabolites is higher than in C2, with a double variation, as the degree of metabolism is diverse. Consecutively, in monoclonal methods, as cross-reactions occur with metabolites, it is more accurate to use the C2 measurement for the evaluation of CyA. The application of both methods, the polyclonal and the monoclonal, could be a useful tool as it gives an estimation of metabolites whose degree of contribution to the immunosuppressive result is difficult to ascertain. Finally, if for reasons of clinical experience, the polyclonal method is used, then the mean therapeutic levels of polyclonal2 are 1.5-1.7 compared with monoclonal2.

Serum concentrations of insulin-like growth factor-I (IGF-I) in patients with liver cirrhosis

BACKGROUND/AIMS

Insulin-like growth factor-I is an important anabolic polypeptide with various effects. The circulating insulin-like growth factor-I is mainly liver derived. The aim of this study was to determine insulin-like growth factor-I serum levels in patients with cirrhosis and to clarify their association with patients' clinical condition and the etiology of cirrhosis.

METHODOLOGY

Forty patients with liver cirrhosis were enrolled. Cirrhosis was in 22 cases induced by virus, in 10 due to primary biliary cause and in the rest 8 of alcoholic origin. The Child score index was found as A (n = 26), B (n = 9), C (n = 5). Twenty, age-matched healthy subjects, were used as a control group. Serum insulin-like growth factor-I was measured by an immunoradiometric assay in all subjects.

RESULTS

Serum insulin-like growth factor-I levels in liver cirrhosis were found very significantly lower than in healthy individuals (57.4 +/- 7.0 ng/mL vs. 198.8 +/- 16.3 ng/mL, p = 0.0000001). In liver cirrhosis insulin-like growth factor-I was negatively correlated with spleen enlargement (r = -0.46, p = 0.0031). Child B and C patients showed significantly reduced insulin-like growth factor-I levels in comparison to patients staged as Child A (28.9 +/- 3.0 ng/mL vs. 72.8 +/- 9.3 ng/mL, p = 0.0016). The comparison of 12 patients with viral induced cirrhosis (Child A) to 14 patients with non-viral cirrhosis, of the same clinical stage, showed non-significant difference (84.2 +/- 16 ng/mL vs. 63.1 +/- 10.3 ng/mL, p = 0.27).

CONCLUSIONS

Insulin-like growth factor-I synthesis is disturbed in liver cirrhosis and reflects the severity of the clinical stage. It represents a good marker of hepatic function. The etiology of cirrhosis does not seem to influence its levels.