The Association between Apolipoprotein E Genotypes and Serum Malondialdehyde Level with End-Stage Renal Disease.

Background: The Apolipoprotein E (ApoE) polymorphism plays an important role in the pathophysiology of end-stage renal disease (ESRD). Additionally, ApoE may contribute to the progression of oxidative stress. Thus, this study aimed to determine the ApoE gene polymorphism and evaluate the malondialdehyde (MDA) level in ESRD patients and healthy individuals. Methods: The present cross-sectional study was conducted at 2010 at Kermanshah University of Medical Sciences (Kermanshah, Iran). The study population comprised ESRD patients (n=136) and healthy individuals (n=137). The MDA level was assessed using high-performance liquid chromatography (HPLC), and the frequencies of ApoE gene alleles were analyzed using restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR). The data were analyzed using Statistical Package for Social Sciences (SPSS), version 13. The significant differences of ApoE genotypes in case and control groups were assessed using Pearson's Chi square tests, and two-tailed Student's tests. A logistic regression model was used to calculate the odd ratio. P<0.05 was considered statistically significant. Results: According to the results, ESRD patients had a higher frequency of the E2/E3 genotype than the healthy group (P<0.001). The results indicated that E3/E4 genotype frequency in the patients' group was higher than that of the control group (P=0.026). Furthermore, the E3/E2 (OR=5.7, 95% CI=2.68-12.14) (P<0.001) and E3/E4 (OR=1.57, 95% CI=1.05-2.34) (P=0.029) genotypes were found to increase the risk of ESRD. Moreover, the MDA level in ESRD patients was higher than the healthy individuals (P<0.001). The patients with E3/E2 (P<0.001) and E3/E4 (P<0.001) genotypes had a higher level of MDA than the control group. Conclusion: According to the findings, patients with ESRD had higher genotypes of E3/E2 and E3/E4, which suggests a higher risk of developing ESRD.

A highly sensitive quantum dots-DNA nanobiosensor based on fluorescence resonance energy transfer for rapid detection of nanomolar amounts of human papillomavirus 18.

A very sensitive and convenient nanobiosensor based on fluorescence resonance energy transfer (FRET) was developed for the detection of a 22-mer oligonucleotides sequence in Human Papillomavirus 18 virus (HPV18) gene. For this purpose, water-soluble CdTe quantum dots (QDs) were synthesized and, subsequently, amino-modified 11-mer oligonucleotide as one of the two necessary probes was attached to QDs surface to form functional QDs-DNA conjugates. Right after addition of the QDs-DNA and a second Cyanine5 (Cy5)-labeled 11-mer oligonucleotide probe to the DNA target solution, the sandwiched hybrids were formed. The resulting hybridization brings the Cy5 fluorophore as the acceptor to close proximity of the QDs as donor, so that an effective transfer of energy from the excited QDs to the Cy5 probe would occur via FRET processing. The fluorescence intensity of Cy5 found to linearly enhance by increasing the DNA target concentration from 1.0 to 50.0nM, with a detection limit of 0.2nM. This homogeneous DNA detection method does not require excessive washing and separation steps of un-hybridized DNA, due to the fact that no FRET can be observed when the probes are not ligated. Finally, feasibility and selectivity of the proposed one-spot DNA detection nanobiosensor were investigated by analysis of derived nucleotides from HPV18 and mismatched sequences.