ALDH1A2 (RALDH2) genetic variation in human congenital heart disease

Abstract\ud \ud \ud \ud Background\ud \ud Signaling by the vitamin A-derived morphogen retinoic acid (RA) is required at multiple steps of cardiac development. Since conversion of retinaldehyde to RA by retinaldehyde dehydrogenase type II (ALDH1A2, a.k.a RALDH2) is critical for cardiac development, we screened patients with congenital heart disease (CHDs) for genetic variation at the ALDH1A2 locus.\ud \ud \ud \ud Methods\ud \ud One-hundred and thirty-three CHD patients were screened for genetic variation at the ALDH1A2 locus through bi-directional sequencing. In addition, six SNPs (rs2704188, rs1441815, rs3784259, rs1530293, rs1899430) at the same locus were studied using a TDT-based association approach in 101 CHD trios. Observed mutations were modeled through molecular mechanics (MM) simulations using the AMBER 9 package, Sander and Pmemd programs. Sequence conservation of observed mutations was evaluated through phylogenetic tree construction from ungapped alignments containing ALDH8 s, ALDH1Ls, ALDH1 s and ALDH2 s. Trees were generated by the Neighbor Joining method. Variations potentially affecting splicing mechanisms were cloned and functional assays were designed to test splicing alterations using the pSPL3 splicing assay.\ud \ud \ud \ud Results\ud \ud We describe in Tetralogy of Fallot (TOF) the mutations Ala151Ser and Ile157Thr that change non-polar to polar residues at exon 4. Exon 4 encodes part of the highly-conserved tetramerization domain, a structural motif required for ALDH oligomerization. Molecular mechanics simulation studies of the two mutations indicate that they hinder tetramerization. We determined that the SNP rs16939660, previously associated with spina bifida and observed in patients with TOF, does not affect splicing. Moreover, association studies performed with classical models and with the transmission disequilibrium test (TDT) design using single marker genotype, or haplotype information do not show differences between cases and controls.\ud \ud \ud \ud Conclusion\ud \ud In summary, our screen indicates that ALDH1A2 genetic variation is present in TOF patients, suggesting a possible causal role for this gene in rare cases of human CHD, but does not support the hypothesis that variation at the ALDH1A2 locus is a significant modifier of the risk for CHD in humans.Work supported by grants from Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) 01/000090; 00/030722; 01/142381; 02/113402; 03/099982; 04/116068; 04/157044 and Conselho Nacional de Desenvolvimento Científico e Tecnológico 481872/20078. We would like to thank the careful work and thoughtful suggestions of the two reviewers responsible for the reviewing editorial process.Work supported by grants from Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) 01/00009-0; 00/03072-2; 01/14238-1; 02/11340-2; 03/09998-2; 04/11606-8; 04/15704-4 and Conselho Nacional de Desenvolvimento Científico e Tecnológico 481872/2007-8. We would like to thank the careful work and thoughtful suggestions of the two reviewers responsible for the reviewing editorial process

Effects of N-Butyl-2-Cyanoacrylate on High-Level Jejunojejunostomy

&lt;i&gt;Background:&lt;/i&gt; Morbidity and mortality due to anastomotic complications in gastrointestinal surgery remain important problems. The tissue adhesive N-butyl-2-cyanoacrylate (NB2CA) is used in many fields of surgery. This study was designed to assess the effects of NB2CA on high-level jejunojejunostomy. &lt;i&gt;Materials and Methods:&lt;/i&gt; Forty male albino Wistar rats were divided into 4 groups of 10 each. The groups were treated as follows: group 1 underwent only a jejunojejunostomy, group 2 underwent jejunojejunostomy followed by NB2CA application around the anastomosis, group 3 underwent jejunojejunostomy after a 60-min ischemia and a 60-min reperfusion, and group 4 underwent jejunojejunostomy after a 60-min ischemia and a 60-min reperfusion followed by NB2CA application around the anastomosis. At postoperative day 7, the subjects in all groups were sacrificed. Intra-abdominal adhesions, anastomotic complications and anastomotic burst pressures (ABP) were recorded. &lt;i&gt;Results:&lt;/i&gt; The analysis of all the groups for adhesion scores and ABP showed statistical significance (p &lt; 0.001). &lt;i&gt;Conclusions:&lt;/i&gt; The use of NB2CA had positive effects in terms of increasing ABP both with and without the initial ischemia- reperfusion insult. However, it had the adverse effect of significantly increasing the number of intra-abdominal adhesions.</jats:p

Effect of angiotensin II type 1 receptor blocker on osteoporotic rat femurs

PubMed ID: 23087139Background: Osteoblasts and osteoclasts are known to express Ang II type I (AT1) receptor in cell cultures, suggesting the existence of local renin-angiotensin system (RAS) in bone. This study was designed to investigate the effects of losartan as AT1 receptor blocker on ovariectomized rats' femur. Methods: Losartan (5 mg/kg/day) was administered via oral gavage for 8 weeks. Bone mineral density (BMD) was measured using dual energy X-ray absorptiometry, while tensile and three-point bending tests were performed for evaluation of biomechanical properties of bone. The trabecular porosity was analyzed by scanning electron microscopy. Results: There was a significant decrease in BMD values of ovariectomized rats' femurs which were reversed by losartan treatment. According to tensile test results, ultimate tensile strength and strain values of losartan treated ovariectomized rats' femurs increased and decreased, respectively, when compared to that of ovariectomized animals. Losartan treatment also caused a significant recovery in flexural strength and modulus parameters regarding respective control values, which mean losartan treated ovariectomized rats' femur had more force tolerance until break than ovariectomized rats' femur. Quantitative microscopic analysis showed larger trabecular porosity in ovariectomized rats than control rat femurs and it was significantly decreased after losartan treatment. Conclusion: Blockage of AT1 receptor increased strength, mass and trabecular connections of ovariectomized rat femurs. Therefore, it is tempting to speculate that drugs, including AT1 receptor blockers, may be used for the treatment of osteoporosis or reduction of its detrimental effects in the future. Copyright © 2012 by Institute of Pharmacology Polish Academy of Sciences.We thank Dr. Ozan AKKUS from Case Western Reserve University, USA for constructive critique of the manuscipt. We thank Dr. Mustafa YILDIZ from Suleyman Demirel University, Turkey for help during DEXA procedures. The study was part of Baris Ozgur Donmez PhD thesis and supported by Akdeniz University Research Fund with number of 2007.03.0122.006. Disclosure of financial conflicts of interest: None. -