Solution and crystal structure of BA42, a protein from the Antarctic bacterium Bizionia argentinensis comprised of a stand-alone TPM domain.

The structure of the BA42 protein belonging to the Antarctic flavobacterium Bizionia argentinensis was determined by nuclear magnetic resonance and X-ray crystallography. This is the first structure of a member of the PF04536 family comprised of a stand-alone TPM domain. The structure reveals a new topological variant of the four ß-strands constituting the central ß-sheet of the αßα architecture and a double metal binding site stabilizing a pair of crossing loops, not observed in previous structures of proteins belonging to this family. BA42 shows differences in structure and dynamics in the presence or absence of bound metals. The affinity for divalent metal ions is close to that observed in proteins that modulate their activity as a function of metal concentration, anticipating a possible role for BA42.

High-dose plasmid-mediated VEGF gene transfer is safe in patients with severe ischemic heart disease (Genesis-I). A phase I, open-label, two-year follow-up trial.

OBJECTIVES: We aimed to assess safety and, secondarily, the efficacy of intramyocardial high-dose plasmid-vascular endothelial growth factor (VEGF) 165 (pVEGF165) gene transfer in no-option patients with coronary artery disease (CAD). BACKGROUND: Controlled trials of pVEGF165 in CAD have shown little benefit. One possible reason is shortness of dosage. We have shown in large mammalian models of chronic myocardial ischemia and acute myocardial infarction that intramyocardial pVEGF165 at doses significantly higher than those used in recent phase II trials is safe and efficacious on myocardial perfusion, left ventricular function, and infarct size limitation. METHODS: Using an injection catheter, 10 patients with severe CAD not amenable for revascularization received 10 intramyocardial injections of 0.38 mg (total dose, 3.8 mg) pVEGF165 in zones exhibiting myocardial ischemia, as assessed by combined stress 99mTc-sestamibi single-photon emission computed tomography and stress echocardiography. RESULTS: No serious adverse events related to either VEGF or the injection procedure occurred over the 2-year follow-up. One patient suffered femoral artery thrombosis after a follow-up coronary angiography, successfully resolved with medical treatment. Six patients suffered uncomplicated coronary ischemic events during the second year follow-up. Angina functional class decreased from 2.6 ± 0.2 to 1.2 ± 0.3 (mean ± SEM, P < 0.05), quality of life increased from 56.9 ± 3.2 to 82.6 ± 2.4 (P < 0.05), the summed difference score of myocardial perfusion decreased from 13.4 ± 2 to 7.7 ± 1.8 (P < 0.04), and stress ejection fraction did not change (44.2 ± 3.6% to 47.8 ± 3.1%, P = NS). CONCLUSIONS: High-dose intramyocardial pVEGF165 is safe at 2 years follow-up in patients with severe CAD. The efficacy results observed must be taken cautiously given the uncontrolled, open-label study design.

Effect of vascular endothelial growth factor gene transfer on infarct size, left ventricular function and myocardial perfusion in sheep after 2 months of coronary artery occlusion.

BACKGROUND: In large mammalian models of acute myocardial infarction (AMI), plasmid-mediated vascular endothelial growth factor (pVEGF) gene transfer has been shown to induce angio-arteriogenesis, proliferation of myocyte precursors and adult cardiomyocyte mitosis, reducing infarct size at 15 days after coronary artery occlusion. However, it is unknown whether these effects persist at longer follow-up times, nor how they affect cardiac performance. We thus assessed infarct size, left ventricular (LV) function and perfusion in 2-month-old ovine AMI. METHODS: Adult sheep with coronary artery occlusion were randomized to blindly receive ten intramyocardial injections of 3.8 mg of pVEGF or empty plasmid distributed at the infarct border. Three and 60 days later, LV perfusion (single-photon emission computed tomography) and function (stress echocardiography) were assessed. Finally, hemodynamics (LV catheterization), scar size and peri-infarct histology were studied. RESULTS: Infarct size was 30% smaller in pVEGF-treated sheep (23.6 ± 1.9% versus 32.7 ± 2.7% of the LV; p < 0.02). Percentage fractional shortening and wall thickening at the infarct border improved after pVEGF, as did myocardial perfusion and LV wall motion under pharmacological stress. Global LV function did not differ between groups, although the force-frequency response was preserved in pVEGF group and lost in placebo animals. These effects were associated with angio-arteriogenesis and proliferation of cardiomyocyte precursors. CONCLUSIONS: In sheep with AMI, pVEGF gene transfer affords long-term infarct size reduction, yielding regional LV function and perfusion improvement and reducing remodeling progression. These results suggest the potential usefulness of this approach in the clinical setting.

Draft genome sequence of Bizionia argentinensis, isolated from Antarctic surface water.

A psychrotolerant marine bacterial strain, designated JUB59(T), was isolated from Antarctic surface seawater and classified as a new species of the genus Bizionia. Here, we present the first draft genome sequence for this genus, which suggests interesting features such as UV resistance, hydrolytic exoenzymes, and nitrogen metabolism.

Long-term effects of growth hormone on infarct size and left ventricular function in sheep with coronary artery occlusion.

The effects of growth hormone (GH) on infarct size and left ventricular (LV) function in experimental acute myocardial infarction (AMI) have been controversial. Moreover, little, if any, information exists regarding long-term evaluation of therapeutic doses of GH in large mammalian models of AMI. We therefore aimed to assess the effect of therapeutic doses of GH over 3.5 months on infarct size and heart function in sheep with AMI. After coronary artery ligation, sheep received subcutaneous human GH 8 IU/d (n = 8) or vehicle (n = 8) over 100 days. Infarct area was similar in GH (16.9% +/- 3% of LV area) and placebo (16.5% +/- 3.7%, P = not significant) sheep. At 3 days of treatment onset, but not at later times, GH sheep had higher LV shortening fraction (30.7% +/- 3.5% vs. 24.8% +/- 6.1%, P < 0.04), systolic anterior wall thickness (10.1 +/- 0.8 vs. 8.6 +/- 1.2 mm, P < 0.02), and cardiac index (3.8 +/- 0.6 vs. 2.8 +/- 0.7 L x min x m, P < 0.01). This evolution of function parameters paralleled that of serum insulin-like growth factor 1 levels, which differed significantly only during the first week, suggesting a direct effect of GH on LV contractility. These results may suggest the usefulness of therapeutic doses of GH at the early phases of AMI but do not support maintaining the treatment for longer time.

Combined VEGF gene transfer and erythropoietin in ovine reperfused myocardial infarction.

BACKGROUND: In reperfused acute myocardial infarction (RAMI), cardioprotective treatments may enhance myocardial salvage and hence reduce the area of necrosis. Based on studies showing that plasmid-mediated vascular endothelial growth factor (pVEGF) gene transfer reduces infarct size by combining angio-arteriogenic and cardiomyogenic effects and that erythropoietin (EPO) exerts anti-apoptotic actions in animal models of AMI, we aimed to assess if their association would reduce infarct size to a larger extent than any of them individually in a large mammalian model of RAMI. METHODS: Adult sheep subjected to 90-minute coronary artery occlusion received upon reperfusion intramyocardial pVEGF 3.8 mg plus intravenous EPO 1000 IU/kg (n=8), pVEGF (n=8), EPO (n=8) or placebo (n=8). RESULTS: Fifteen days after treatment, infarct size was smaller in the 3 treatment groups (pVEGF+EPO: 8 ± 1 %; pVEGF: 16 ± 5 %; EPO: 13 ± 4 %) compared to placebo (25 ± 7 %, p<0.001). However, in the EPO+VEGF group infarct size was significantly smaller than in the groups receiving EPO or VEGF individually (p<0.05). DNA fragmentation, a hallmark of late apoptosis, was significantly lower in sheep receiving EPO. The combined treatment, while not affecting global left ventricular performance, improved regional peri-infarct function and prevented over-time expansion of the post-infarct perfusion defect. CONCLUSIONS: Combined pVEGF and EPO treatment might be clinically useful to enhance the benefits of early revascularization in patients with acute myocardial infarction.

1H, 15N and 13C chemical shift assignments of the BA42 protein of the psychrophilic bacteria Bizionia argentinensis sp. nov.

BA42 is a protein belonging to the psychrophilic bacteria Bizionia argentinensis sp. nov. Bioinformatics analysis showed that it presents significant sequence identity with a Pfam A family, DUF 477, found both in eukarya and eubacteria but of unknown function in all these organisms. Here, we report the NMR spectra assignment of this 145 amino acid protein. These data will allow performing NMR structural studies with the aim of using the three-dimensional structure as relevant information in order to determine the function of this family of proteins.

Bizionia argentinensis sp. nov., isolated from surface marine water in Antarctica.

A marine bacterial strain, designated strain JUB59(T), was isolated from surface seawater in Antarctica and subsequently characterized. Cells were found to be Gram-negative, non-motile rods forming butyrous, shiny, yellowish orange colonies on marine agar. Growth occurred at 2-28 degrees C (optimally at 22-25 degrees C) but not at 30 degrees C; Na+ ions were required, but 9 % NaCl (w/v) was not tolerated. Phylogenetic analysis, based on comparisons of the complete 16S rRNA gene sequence of the novel isolate with the sequences of closely related strains, showed that strain JUB59(T) belonged to the family Flavobacteriaceae, representing a novel species of the genus Bizionia. The highest levels of sequence similarity were found with respect to Bizionia myxarmorum ADA-4(T) (97.4 %) and Bizionia algoritergicola APA-1(T) (97.1 %). However, the DNA-DNA relatedness of strain JUB59(T) with respect to these two strains was low (15.9-17.3 and 19.3-22.1 %, respectively). The predominant fatty acids of strain JUB59(T) were iso-15 : 1omega10c (18.1 %), iso-15 : 0 (17.3 %), anteiso-15 : 0 (13.9 %), iso-17 : 0 3-OH (9.2 %), 15 : 0 (6.0 %) and iso-16 : 0 3-OH (5.3 %). The main polar lipids were phosphatidylethanolamine, an aminolipid, an amino-positive phospholipid and two unidentified lipids. MK-6 was the major respiratory quinone (>90 %) and the DNA G+C content was 34 mol%. On the basis of the data obtained, strain JUB59(T) represents a novel species of the genus Bizionia, for which the name Bizionia argentinensis sp. nov. is proposed. The type strain is JUB59(T) (=DSM 19628(T)=CCM-A-29 1259(T)).

Expresión y efecto del gen de VEGF165 humano en músculo esquelético isquémico de conejos. ¿Necesidad de administración repetitiva para el tratamiento de la enfermedad vascular periféica? / Expression and effects after VEGF165 gene transfer: is it necessary the reiterative administration for the treatment of peripheral vascular disease?

Peripheral vascular disease is a disorder fifficult to treat. Due to the lack of an effective pharmacological therapy, the ischemia of an effective pharmacological therapy, the ischemia of the lower limbs pursues a relentless course, ending many times in the amputation...The authors present in this study a 6 years experience with this management, and recently the effects of an experimental model of peripheral vascular disease in rabbits is evaluated. The results obtained in this study are important because they could attribute to he trnasitority of the genetic expression the contradictory results founded in clinical assays of peripheral vascular disease

Expresión y efecto del gen de VEGF165 humano en músculo esquelético isquémico de conejos. ¿Necesidad de administración repetitiva para el tratamiento de la enfermedad vascular periféica? / Expression and effects after VEGF165 gene transfer: is it necessary the reiterative administration for the treatment of peripheral vascular disease?

Peripheral vascular disease is a disorder fifficult to treat. Due to the lack of an effective pharmacological therapy, the ischemia of an effective pharmacological therapy, the ischemia of the lower limbs pursues a relentless course, ending many times in the amputation...The authors present in this study a 6 years experience with this management, and recently the effects of an experimental model of peripheral vascular disease in rabbits is evaluated. The results obtained in this study are important because they could attribute to he trnasitority of the genetic expression the contradictory results founded in clinical assays of peripheral vascular disease