Do WHO-ISH guidelines identify high risk mild hypertensive patients?

OBJECTIVE: To assess the ability of 1993 WHO-ISH recommendations to identify patients who need drug treatment. METHODS: 268 hypertensive patients with suspected mild hypertension were preselected for this study at their first visit at the referral center. 123 were included after a short in-hospital work-up when they fulfilled the 1993 WHO-ISH criteria for mild hypertension (90-105 mmHg diastolic BP and/or 140-180 mmHg systolic BP). Echocardiography was performed in all patients by the same investigator according to ASE convention. The combined 10-year risk of stroke and coronary heart disease was calculated with the Framingham equation. Patients were then followed up for six months by the same physician blinded to echographic results and risk calculations and applying the WHO-ISH guidelines (monthly BP measurement and subjective assessment of risk). Five patients were excluded, for reasons unrelated to the protocol. RESULTS: The decision of drug treatment was taken at the 1st, 2nd, 3rd, 4th, 5th, 6th monthly visit after work-up in 2, 6, 25, 7, 2 and 6 patients, respectively. Among these 118 patients, 48 patients (29 male, 19 female) were eventually treated and 70 (49 male, 30 female) remained untreated. BP s at preselection and on a day of work-up were similar in both groups. Patients in whom drug treatment was prescribed were older and had higher lef ventricular mass (LVM) than untreated patients, but only 2 of them (all in the treated group) had LVM values above usual thresholds (LVM > 125 g/m2, in men and women). Stroke and coronary risks were both higher in treated than in untreated patients (p < 0.05). The physician using the guidelines decided to treat only 19 of the 38 patients with a 10-year risk < 10% (true positive), whereas she decided to treat with drugs 12 patients among the 44 with a 10-year risk < 5%. CONCLUSION: The difference in LVM between untreated and treated patients support the validity of the WHO-ISH guidelines, but the measurement of LVM did not bring much information for managing the individual patient. Application of these guidelines did not satisfactorily identify high risk patients and could lead to over-treatment of low risk patients.     

Vascular and cardiac remodeling in world class professional cyclists

BACKGROUND: Numerous studies have demonstrated that left ventricular (LV) hypertrophy is often associated with conditioning. METHODS AND RESULTS: The aim of the study was to evaluate cardiac and carotid artery changes induced by professional cycling. We collected M-mode left ventricle and B-mode right common carotid artery data from 149 male professional cyclists before the 1995 "Tour de France" race and 52 male control subjects. LV mass indexed to body surface area in cyclists was double that in control subjects, with no overlap of 95% confidence intervals (cyclists 100.9 to 187 g/m2 and control subjects 51.8 to 96.3 g/m2). Both mean arterial diameter and mean arterial diastolic intima-media thickness (IMT) were 13% higher in cyclists than in control subjects, with overlap of 95% confidence intervals (for arterial IMT 0.45 to 0.65 mm in cyclists and 0.38 to 0.60 mm in control subjects). CONCLUSIONS: Our results suggest that intense cycling has an effect on the cardiovascular system, more pronounced on the left ventricle and less pronounced on large arteries. Nevertheless, athletic training should be considered as a potential determinant of carotid modification.     

Wideband frequency and in situ characterization of aluminum nitride (AlN) in a metal/insulator/metal (MIM) configuration

This paper deals with the electrical wideband frequency and in situ characterization of aluminum nitride (AlN) material. This material is interesting for bulk acoustic wave (BAW) or surface acoustic wave (SAW) devices. In a first step, low frequency characterizations allow to know current versus voltage characteristics, leakages and temperature dependence of the electrical properties. Then, AlN properties in an integrated “metal/insulator/metal” configuration are characterized using MIM waveguide and RLCG parameters are measured up to 20 GHz. An electrical field breakdown of 7.5 MV cm⁻¹ and a relative permittivity between 9 and 10 are extracted. Acoustic resonances, validated with Mason one-dimensional simulation, occur near 5 and 12 GHz. Finally, the MIM devices performances are determined in a wideband frequency: from 1 MHz to 10 GHz.     

Improvement of Capacitive Behavior on Gradient-Free PZT Thin Films

PbZr_0,52Ti_0,48O₃ thin films were synthetized by sol-gel techniques on large scale Pt(111)/TiO_x/SiO₂/Si substrates (200 mm in diameter). The Zr/Ti ratio gradient – that appears through the thickness of the layer with standard processing – can be reduced using an optimized “gradient-compensated” approach. Capacitance measurements revealed an augmentation of the effective permittivity from 5 to 15% using “gradient-free” PZT (reaching 1700 for 2μm). Large scale breakdown voltage analysis revealed an increase of 20% for the breakdown field for low thicknesses (1.25MV/cm for 240 nm-thick layer) suitable for capacitor integration.     

Irradiated bilayer graphene

We describe the gated bilayer graphene system when it is subjected to intense terahertz frequency electromagnetic radiation. We examine the electron band structure and density of states via exact diagonalization methods within Floquet theory. We find that dynamical states are induced which lead to modification of the band structure. We first examine the situation where there is no external magnetic field. In the unbiased case, dynamical gaps appear in the spectrum which manifest as dips in the density of states. For finite inter-layer bias (where a static gap is present in the band structure of unirradiated bilayer graphene), dynamical states may be induced in the static gap. These states can show a high degree of valley polarization. When the system is placed in a strong magnetic field, the radiation induces coupling between the Landau levels which allows dynamical levels to exist. For strong fields, this means the Landau levels are smeared to form a near-continuum of states.     

Nanoparticles for targeted cancer radiotherapy

Radiotherapy, where ionizing radiation is locally delivered either through an external beam or by surgically implanting radionuclide-based seeds in the tumor, is one of the gold standard treatments for cancer. Due to the non-selective nature of radiation, healthy tissue surrounding the cancerous region is usually affected by the treatment. Hence, new strategies, including targeted alpha therapy, are being studied to improve the selectivity of the treatment and minimize side effects. Several challenges, however, limit the current development of targeted radiotherapy, such as the functionalization of the therapeutic agent with targeting vectors and controlling the release of recoiling daughters. Nanoparticles offer unique opportunities as drug delivery vehicles, since they are biocompatible, enhance the cellular uptake of drugs, and are easily functionalized with targeting molecules. In this review, we examine how nanoparticles can be used for targeted radiotherapy, either as sensitizers of external beams or as delivery vehicles for therapeutic radionuclides. We describe the clinical relevance of different types of nanoparticles, followed by an analysis of how these nanoconstructs can solve some of the main limitations of conventional radiotherapy. Finally, we critically discuss the current situation of nanoparticle-based radiotherapy in clinical settings and challenges that need to be overcome in the future for further development of the field.

     

"Hidden" dUTPase sequence in human immunodeficiency virus type 1 gp120

A coding region homologous to the sequence for essential eukaryotic enzyme dUTPase has been identified in different genomic regions of several viral lineages. Unlike the nonprimate lentiviruses (caprine arthritis- encephalitis virus, equine infectious anemia virus, feline immunodeficiency virus, and visna virus), where dUTPase is integrated into the pol coding region, this enzyme has never been demonstrated to be present in the primate lentivirus genomes (human immunodeficiency virus type 1 [HIV-1], HIV-2, or the related simian immunodeficiency virus). A novel approach allowed us to identify a weak but significant sequence similarity between HIV-1 gp120 and the human dUTPase. This finding was then extended to all of the primate lentivirus lineages. Together with the recently reported fragmentary structural similarity between the V3 loop region and the Escherichia coli dUTPase (P. D. Kwong, R. Wyatt, J. Robinson, R. W. Sweet, J. Sodroski, and W. A. Hendrickson, Nature 393:648-659, 1998), our results strongly suggest that an ancestral dUTPase gene has evolved into the present primate lentivirus CD4 and cytokine receptor interacting region of gp120.     

Incidence of inflammatory bowel diseases in the department of Puy-de-D?me in 1993 and 1994. EPIMICI. Epidémiologie des Maladies Inflammatoires Cryptogenetiques de l'Intestin group

The aim of this prospective epidemiological study was to investigate the incidence of Inflammatory Bowel Disease in the Puy-de-D?me county using the same methodology as EPIMAD's registry. METHODS: From 01/01/93 to 31/12/94, each gastroenterologist (n = 22) collected patients consulting for the first time with clinical symptoms compatible with inflammatory bowel disease. Data were reported on a questionnaire by an interviewer practitioner. The final diagnosis of Crohn's disease and ulcerative colitis was made in a blind manner by two expert gastroenterologists and recorded according to the Calkin's criteria as definite, probable, or possible diagnosis, or unclassifiable chronic colitis or acute colitis. RESULTS: 167 new cases were identified: 112 (67.1%) inflammatory bowel disease for the combined group of definite and probable cases with 79 Crohn's disease (70.5%), 29 ulcerative colitis (25.9%) of which 11 ulcerative proctitis (37.9%), 4 unclassifiable chronic colitis (3.6%) and 55 acute colitis (32.9%). The crude and age-adjusted incidence (per 10(5)/year) was respectively 6.6 and 5.7 for Crohn's disease and 2.4 and 1.9 for ulcerative colitis. The highest age-specific incidence rate for Crohn's disease was between 40-49 years (14.1) and for ulcerative colitis between 80-89 years (6.8). The female/male ratio was 0.8 for Crohn's disease and 1.1 for ulcerative colitis. The median age at the time of diagnosis was 42.6 years for Crohn's disease and 35.3 years for ulcerative colitis. CONCLUSIONS: These preliminary findings revealed a high incidence of Crohn's disease and low of ulcerative colitis in this county. However, these results must be managed carefully because these data were recorded only on two years and the inflammatory bowel disease classified possible and acute colitis require a follow-up.