Echocardiographic follow-up after implanting 17-mm Regent mechanical prostheses

The aim of this study was to evaluate midterm echocardiographic results and changes in quality of life after aortic valve replacement with 17-mm St. Jude Medical Regent mechanical prostheses in patients with aortic valve stenosis. The study population was 34 women and 2 men, aged 31-83 years. Echocardiographic follow-up was 100% complete at 4.1 +/- 1.8 years. Hospital mortality was 5.6%. Actuarial 5-year survival was 88.5% +/- 0.067%. Postoperative echocardiography showed significant regression of left ventricular mass index and significant reductions of peak gradient, mean gradient and mean effective orifice area index. All survivors were interviewed using the 36-item Short Form Health Survey questionnaire. Scores obtained in 7 of the 8 domains of the test were significantly higher than preoperative values. In our experience, implantation of this prosthesis allowed regression of left ventricular mass index and improved the perceived quality of life.     

Coronary Arteries Simplified with 3D Cylinders to Assess True Bifurcation Angles in Atherosclerotic Patients

The geometry of coronary arteries affects regional atherogenic processes. Accurate images can be assessed using multislice computer tomography (MSCT) to estimate bifurcations angles. We propose a three-dimensional (3D) method to measure true bifurcation angles of coronary arteries and to determine possible correlations between plaque presence and angulations. The left main (LM) coronary artery, left anterior descendent (LAD) and left circumflex artery (LCX) were imaged in 40 atherosclerotic and 35 healthy patients, using 64-rows MSCT. This Y-junction was simplified fitting a 3D cylinder to each vessel to estimate true bifurcation angles and diameters. The method was tested in phantoms and interobserver variability was assessed. Geometrical results were compared between groups using an unpaired t-test. The cylinders fitted reasonably well with mean distances to measured points below 0.4 mm. LAD–LCX bifurcation angles were wider in the atherosclerotic group (p < 0.01). LAD (p < 0.01) and LCX (p < 0.05) diameters were also larger. In phantoms mean absolute difference between true and estimated angles (N = 27) was 0.44 ± 0.54°. Interobserver mean difference (N = 135) was 1.8 ± 5.8°. Simplifying coronary bifurcation with cylinders results in a reliable technique to assess coronary artery geometry in 3D, avoiding planar projections and decreasing interobserver variability. Geometrical risk factors should be incorporated to properly predict atherosclerosis processes.     

Corrosion Behavior of Titanium Dental Implants with Implantoplasty

The procedure generally used to remove bacterial biofilm adhering to the surface of titanium on dental implants is implantoplasty. This treatment is based on the machining of the titanium surface to remove bacterial plaque. In this study, we used 60 grade 4 titanium implants and performed the implantoplasty protocol. Using X-ray diffraction, we determined the stresses accumulated in each of the as-received, machined and debris implants. The resistance to corrosion in open circuit and potentiodynamically in physiological medium has been determined, and the corrosion potentials and intensities have been determined. Tests have been carried out to determine ion release by ICP-MS at different immersion times. The results show that the corrosion resistance and the release of titanium ions into the medium are related to the accumulated energy or the degree of deformation. The titanium debris exhibit compressive residual stresses of −202 MPa, the implant treated with implantoplasty −120 MPa, and as-received −77 MPa, with their corrosion behavior resulting in corrosion rates of 0.501, 0.77, and 0.444 mm/year, respectively. Debris is the material with the worst corrosion resistance and the one that releases the most titanium ions to the physiological medium (15.3 ppb after 21 days vs. 7 ppb for as-received samples). Pitting has been observed on the surface of the debris released into the physiological environment. This behavior should be taken into account by clinicians for the good long-term behavior of implants with implantoplasty.     

Regional mapping of RBP4 to 10q23→q24 and RBP1 to 3q21→q22 in man

The human gene coding for RBP4 has been assigned to 10q2324 using a panel of somatic cell hybrids and in situ hybridization experiments. The mapping of the human RBP1, previously assigned by our group to chromosome 3 using a panel of somatic cell hybrids, was restricted to the region 3q2122 using in situ experiments and Southern blots of genomic DNA from a hybrid retaining a portion of chromosome 3.R.F. is recipient of a Research Grant from A.I.R.C.     

Plasma lipid peroxidation in sporadic Parkinson's disease. Role of the L-dopa

Oxidative stress plays an important role in the pathogenesis of neurodegenerative diseases, such as Parkinson's disease (PD). There are several methods to measure oxidative stress, being lipid peroxidation (LPO) one of the most frequently used. Endogenous plasma LPO was determined by a spectrofluorimetric method in fifty two patients with sporadic PD and in forty controls. To know the maximum capacity of lipids to peroxidate, LPO was also measured after co-incubation with Fe2+/H2O2 (exogenous LPO). All PD patients were taken L-dopa and the effect of this treatment on LPO levels was additionally studied. Urine catecholamines and their main metabolites were also analyzed, and their possible correlation to LPO statistically studied. Endogenous plasma LPO levels were 33% higher in PD group than in control group (P<0.001). Exogenous plasma or oxidizability was also higher in PD patients compared to controls (20%, P<0.05). The intake of L-dopa was negatively dose-related to endogenous and exogenous plasma LPO. In conclusion, plasma of PD patients has elevated levels of LPO and also is more prone to peroxidation than that in the control group. The results also suggest an antioxidant effect of L-dopa.     

Episodic memory in progressive supranuclear palsy: a neuropsychological and neuroimaging study

Neurological Sciences - Episodic memory impairment may occur in progressive supranuclear palsy (PSP). However, it remains uncertain whether this is due to executive dysfunction or to the...     

Thalamo-cortical networks in subtypes of migraine with aura patients

BackgroundWe searched for differences in resting-state functional connectivity (FC) between brain networks and its relationship with the microstructure of the thalamus between migraine with pure visual auras (MA), and migraine with complex neurological auras (MA+), i.e. with the addition of at least one of sensory or language symptom.Methods3T MRI data were obtained from 20 patients with MA and 15 with MA + and compared with those from 19 healthy controls (HCs). We collected resting state data among independent component networks. Diffusivity metrics of bilateral thalami were calculated and correlated with resting state ICs-Z-scores.ResultsAs compared to HCs, both patients with MA and MA + disclosed disrupted FC between the default mode network (DMN) and the right dorsal attention system (DAS). The MA + subgroup had lower microstructural metrics than both HCs and the MA subgroup, which correlated negatively with the strength of DMN connectivity. Although the microstructural metrics of MA patients did not differ from those of HCs, these patients lacked the correlation with the strength of DAS connectivity found in HCs.ConclusionsThe present findings suggest that, as far as MRI profiles are concerned, the two clinical phenotypes of migraine with aura have both common and distinct morpho-functional features of nodes in the thalamo-cortical network.     

Vaccinia virus recombinants as a model system to analyze interferon-induced pathways.

The interferons (IFNs) are a family of cytokines with broad antiviral activities that also control cell proliferation and modulate immune responses. IFNs exert their pleiotropic actions through the regulation of multiple pathways that have been subjected to extensive study using diverse approaches. The scope of this review is to show how we can take advantage of vaccinia virus (VV) to study IFN-related pathways. We summarize and present the different VV models available for studying IFN function and the possibilities that they offer to analyze IFN-induced pathways, IFN modulators, and the biologic effects at the molecular and cellular levels. Emphasis is given to studies of dsRNA-activated signaling with VV lacking E3L (VV DeltaE3L) and in RNA-activated protein kinase (PKR)-related pathways, through the use of VV recombinants (VVr) with inducible PKR (VV PKR). The latest system is versatile, as expression of PKR can be regulated and induced at different times; similarly, VVr can be generated expressing other PKR modulators. As an example of the utility of VVr, we describe how this model has been used to analyze the antiviral and proapoptotic functions of PKR, the impact of PKR on translation, and the PKR-induced activation of the nuclear factor-kappaB (NF-kappaB) pathway.