Estimation of oxidative stress and its correlation with uterine arteries Doppler velocimetry in women with preeclampsia

OBJECTIVES: Estimation of oxidative stress through the measurement of lipid peroxides and malondialdehyde serum concentration as well as serum antioxidants level expressed by total antioxidants status and its correlation with Doppler velocimetry in women with preeclampsia. MATERIAL AND METHODS: Thirty four patients with preeclampsia at third trimester of gestation: 19 with the mild form and 15 with the severe form of the disease, 21 women with uncomplicated pregnancy at third trimester of gestation served as a control group. Colorimetric methods were used to estimate lipid peroxides, malondialdehyde and antioxidants serum level. In each patient Pulsatility Index and Uterine Artery Score in uterine arteries was measured. RESULTS: Serum concentration of lipid peroxides and malondialdehyde was the highest in patients with severe preeclampsia, but the statistical difference concerned only lipid peroxides level which was significantly higher in this group than in women with mild form of the disease and in the control group. Pulsatility index Uterine Artery Score values were significantly higher in women with severe preeclampsia in comparison to two other groups of patients. Lipid peroxides level significantly positively correlated with Pulsatility Index and Uterine Artery Score values in the whole studied population. CONCLUSIONS: Only severe form of preeclampsia is associated with oxidative stress which impaired placenta perfusion expressed by the increase of uterine arteries resistance.     

Differentiation of HL-60 myeloid leukemia cells induced by all-trans retinoic acid is enhanced in combination with caffeic acid

We investigated a possible enhancement of all-trans retinoic acid (ATRA)-induced differentiation of HL-60 human myeloid leukemia cells by caffeic acid (CA), a widely distributed plant phenolic compound. Our results showed that CA, in the concentration of 13 or 52 micro M, had no or minimal influence on cell differentiation, whereas the differentiating activity of ATRA was potentiated by CA treatment. We proved, using flow cytometric detection of the CD66b surface molecule, a synergistic effect of CA: at day 10, 18.3% of CD66b-positive cells were detected after treatment with ATRA only, and 33% when CA and ATRA were combined together. NBT-assay confirmed that this additive effect of CA on ATRA-induced differentiation. Proliferating activity as assessed by MTT-assay was generally not affected by CA at given concentrations. However, cell proliferation was significantly reduced by 52 micro M CA at 96-h intervals. This effect was markedly enhanced when CA, at both concentrations, and ATRA were combined. The possibility to enhance the differentiation potential of ATRA by CA may improve outcomes in the therapy of acute promyelocytic leukemia.     

The effects of paclitaxel on the three phases of restenosis: smooth muscle cell proliferation, migration, and matrix formation: an in vitro study

PURPOSE: We sought to evaluate the growth-modulating potential of paclitaxel on cultured human arterial smooth muscle cells depending on the administered dose. MATERIAL AND METHODS: For all experiments human arterial smooth muscle cells (SMCs) were used. SMCs were either cultured for 5 days or for 20 days with paclitaxel (doses: 10(-7) M, 10(-8) M, 10(-9) M). For a total period of 20 days, proliferation kinetics of the SMC were analyzed. To assess the clonogenic activity of the SMC colony-forming assays were performed. Drug- and dose-dependent cell cycle changes were analyzed by flow cytometry. The effect on cell migration was examined in a 2-chamber migration system. The effects of paclitaxel on the synthesis of tenascin were examined via immunofluorescence. RESULTS: Depending on the dose administered, paclitaxel proved to inhibit SMC proliferation effectively when administered during the total period of 20 days. When incubated for 5 days with doses of paclitaxel ranging between 10(-8) M and 10(-9) M, SMCs showed clear signs of regeneration. When being incubated with 10(-7) M of paclitaxel, however, SMCs reacted with a reduction in cell proliferation, a reduced clonogenic activity, and a drug-induced G2/M phase block. SMC migration was inhibited effectively as well as extracellular matrix formation. CONCLUSION: Paclitaxel is a potent inhibitor of SMC proliferation, SMC migration, and extracellular matrix formation in vitro, with all three phases of the restenosis process inhibited effectively.     

Intramedullary abscess of the spinal cord in children: a case report and review of the literature

A case report of an intramedullary spinal cord abscess in a 13-month-old boy and a review of relevant existing pediatric literature is presented. Thirty-eight cases of pediatric intramedullary spinal cord abscess are analyzed for presenting signs and symptoms, microbiology of isolated organisms, surgical intervention, antibiotic administration and outcome. The most significant variable on outcome is timely surgical intervention, followed by appropriate antibiotic administration.     

Transplacental and other routes of cancer transmission between individuals

Cancer in pregnancy is not rare, and the possibility of transmission of malignancy from mother to child, while infrequent, represents a clinical challenge for the primary pediatric hematologist-oncologist. The authors summarize all reported cases of vertically transmitted cancer and review other reported cases of person-to-person transfer of malignancy. As these cases represent a unique physiologic model of tumor transplantation, the biology of cancer transmission is discussed and provisional guidelines are given for the screening of infants born to women with cancer.     

The stereospecificity of flobufen metabolism in isolated guinea pig hepatocytes

Background

Extracellular nucleotides play an important role in the regulation of vascular tone and may be involved in cerebral vasospasm after subarachnoidal haemorrhage. This study was designed to characterise the contractile P2 receptors in endothelium-denuded human cerebral and omental arteries. The isometric tension of isolated vessel segments was recorded in vitro. P2 receptor mRNA expression was examined by RT-PCR.

Results

In human cerebral arteries, the selective P2Y₆ receptor agonist, UDPβS was the most potent of all the agonists tested (pEC₅₀ = 6.8 ± 0.7). The agonist potency; UDPβS > αβ-MeATP > UTPγS > ATPγS > ADPβS = 0, indicated the presence of contractile P2X₁ P2Y₂, P2Y₄ and P2Y₆, but not P2Y₁ receptors, in human cerebral arteries. In human omental arteries, UDPβS was inactive. The agonist potency; αβ-MeATP > ATPγS = UTPγS > ADPβS = UDPβS = 0, indicated the presence of contractile P2X₁, and P2Y₂ receptors, but not P2Y₁ or P2Y₆ receptors, in human omental arteries. RT-PCR analysis of endothelium-denuded human cerebral and omental arteries demonstrated P2X₁, P2Y₁, P2Y₂ and P2Y₆ receptor mRNA expression. There were no bands for the P2Y₄ receptor mRNA in the omental arteries, while barely detectable in the cerebral arteries.

Conclusions

P2Y₆ receptors play a prominent role in mediating contraction of human cerebral arteries. Conversely, no such effect can be observed in human omental arteries and previous results confirm the absence of P2Y₆ receptors in human coronary arteries. The P2Y₆ receptor might be a suitable target for the treatment of cerebral vasospasm.