Maternal and cord serum lipid profiles of preterm infants with respiratory distress syndrome

Background: Lipid metabolism has an important role in fetal development during the late stage of gestation, including growth and fat accretion in utero, increasing amniotic fluid lecithin levels with maturation of pulmonary function and changes in the levels of minor phospholipids in amniotic fluid

Efficiency of lasers and a desensitizer agent on dentin hypersensitivity treatment: a clinical study

Aim: The aim of this clinical study was to determine and compare the efficiency of the glutaraldehyde-containing agent (GCA), Nd:YAG, Er,Cr:YSGG lasers, and the combination of them on the dentin hypersensitivity (DH) treatment.Subjects and Methods: This study was performed with the participation of 17 healthy adult patients having 100 teeth with DH; the patients were randomly divided into five groups according to the treatment protocol: (1) application of GCA on sensitive teeth, (2) Nd:YAG laser (1 W/cm2, 10 Hz) irradiation on sensitive teeth, (3) application of GCA on sensitive teeth and then Nd:YAG laser irradiation, (4) Er,Cr:YSGG laser (0.25 W/cm2, 20 Hz) irradiation on sensitive teeth, (5) application of GCA on sensitive teeth and then Er,Cr:YSGG laser irradiation. Sensitivity levels were assessed by the Yeaple probe on the buccal surfaces of the teeth at a force setting of 10 g. Measurements were performed for 30 min, after 7, 90, and 180 days of the therapy to assess the effects of desensitization. The evaluations were analyzed using the one-way analysis of variance and repeated measurement test (P < 0.05).Results: After sessions, DH was significantly reduced in all groups at each measurement point. The Er,Cr:YSGG laser with or without GCA application were the most effective ones in DH treatment (P < 0.05). Comparison of the treatment regimens demonstrated that the scores achieved with the Yeaple probe were not significantly higher for the Nd:YAG laser groups than the GCA alone group.Conclusions: This clinical study shows that the Er,Cr:YSGG laser have promising potential for the treatment of DH.Keywords: Dentin hypersensitivity, Er,Cr:YSGG laser, Nd:YAG laser, Yeaple prob

Numerical Characterization of In Vivo Wireless Communication Channels

In this paper, we numerically investigated the in vivo wireless communication channel for human male torso at 915 MHz. Results show that in vivo channel is different than the classical communication channel and location dependency is very critical for link budget calculations. A statistical path loss model based on angle, depth and body region is introduced for near and far field regions. Furthermore, multipath characteristics are investigated using a power delay profile as well

Magnetic resonance molecular imaging contrast agents and their application in atherosclerosis

Heart disease is the most prevalent cause of mortality in the Western world and is most frequently caused by rupture of lesions in the arteries, which are formed by atherosclerosis. Atherosclerosis is a progressive disease, and therefore, there is a strong motivation to be able to image the stages of this disease in vivo. The pathogenesis of this disease is now well established, and a number of markers such as macrophages, vascular adhesion molecules, fibrin, and the alphanubeta3-integrin have been identified that are of particular interest for imaging. Furthermore, the differentiation between the stable and unstable plaque with imaging is a central goal of the field. Contrast can be generated in magnetic resonance imaging through the application of several types of agents such as T1, T2, chemical exchange saturation transfer or 19F-based imaging agents. Subsequent to the discussion of the above topics, we will describe some examples of molecular imaging agents that successfully detect specific markers in atherosclerotic plaques that are of interest in several stages of this diseas

Incorporation of an apoE-derived lipopeptide in high-density lipoprotein MRI contrast agents for enhanced imaging of macrophages in atherosclerosis

Magnetic resonance (MR) imaging is becoming a pivotal diagnostic method to identify and characterize vulnerable atherosclerotic plaques. We previously reported a reconstituted high-density lipoprotein (rHDL) nanoparticle platform enriched with Gd-based amphiphiles as a plaque-specific MR imaging contrast agent. Further modification can be accomplished by inserting targeting moieties into this platform to potentially allow for improved intraplaque macrophage uptake. Since studies have indicated that intraplaque macrophage density is directly correlated to plaque vulnerability, modification of the rHDL platform may allow for better detection of vulnerable plaques. In the current study we incorporated a carboxyfluoresceine-labeled apolipoprotein E-derived lipopeptide, P2fA2, into rHDL. The in vitro macrophage uptake and in vivo MR efficacy were demonstrated using murine J774A.1 macrophages and the apolipoprotein E knock-out (apoE(-/-)) mouse model of atherosclerosis. The in vitro studies indicated enhanced association of murine macrophages to P2fA2 enriched rHDL (rHDL-P2A2) nanoparticles, relative to rHDL, using optical techniques and MR imaging. The in vivo studies showed a more pronounced and significantly higher signal enhancement of the atherosclerotic wall 24 h after the 50 micromol Gd/kg injection of rHDL-P2A2 relative to administration of rHDL. The normalized enhancement ratio for atherosclerotic wall of rHDL-P2A2 contrast agent injection was 90%, while that of rHDL was 53% 24 h post-injection. Confocal laser scanning microscopy revealed that rHDL-P2A2 nanoparticles co-localized primarily with intraplaque macrophages. The results of the current study confirm the hypothesis that intraplaque macrophage uptake of rHDL may be enhanced by the incorporation of the P2fA2 peptide into the modified HDL particl

Magnetic resonance molecular imaging of thrombosis in an arachidonic acid mouse model using an activated platelet targeted probe

Atherosclerotic plaque rupture leads to acute thrombus formation and may trigger serious clinical events such as myocardial infarction or stroke. Therefore, it would be valuable to identify atherothrombosis and vulnerable plaques before the onset of such clinical events. We sought to determine whether the noninvasive in vivo visualization of activated platelets was effective when using a target-specific MRI contrast agent to identify thrombi, hallmarks of vulnerable or high-risk atherosclerotic plaques. Inflammatory thrombi were induced in mice via topical application of arachidonic acid on the carotid. Thrombus formation was imaged with intravital fluorescence microscopy and molecular MRI. To accomplish the latter, a paramagnetic contrast agent (P975) that targets the glycoprotein alpha(IIb)beta(3), expressed on activated platelets, was investigated. The specificity of P975 for activated platelets was studied in vitro. In vivo, high spatial-resolution MRI was performed at baseline and longitudinally over 2 hours after injecting P975 or a nonspecific agent. The contralateral carotid, a sham surgery group, and a competitive inhibition experiment served as controls. P975 showed a good affinity for activated platelets, with an IC(50) (concentration of dose that produces 50% inhibition) value of 2.6 micromol/L. In thrombosed animals, P975 produced an immediate and sustained increase in MRI signal, whereas none of the control groups revealed any significant increase in MRI signal 2 hours after injection. More important, the competitive inhibition experiment with an alpha(IIb)beta(3) antagonist suppressed the MRI signal enhancement, which is indicative for the specificity of P975 for the activated platelets. P975 allowed in vivo target-specific noninvasive MRI of activated platelet

Well-defined, multifunctional nanostructures of a paramagnetic lipid and a lipopeptide for macrophage imaging

In the field of nanomedicine there is a great demand for technologies that allow the creation of self-assembled structures of which the size and morphology can be accurately controlled. In the current study, we report a nanoparticle platform that is composed of a paramagnetic lipid and a fluorescently labeled lipopeptide. By judiciously controlling the ratio of the aforementioned amphiphilic molecules, a variety of well-defined nanosized supramolecular structures with different sizes and morphologies could be created. The hydrodynamic radii of the different structures were determined by dynamic light scattering. Cryo-TEM revealed the aggregate morphology to vary from small micellar structures to plate-like and even full grown ribbons of which the aspect ratios varied from a diameter of 5-8 nm to structures with a width of up to 25 nm and infinite length. Interestingly, nuclear magnetic resonance dispersion profiling revealed excellent properties for MRI and also showed that the relaxivity of the structures was tunable and morphology dependent. Finally, macrophage cells were treated with two selected nanoparticles and were shown to be avidly taken up. In conclusion we demonstrate a methodology to create structures that (1) are paramagnetic to enable their detection with MRI, (2) exhibit fluorescent properties, (3) can be tuned to defined sizes and shapes, and (4) are efficiently taken up by macrophage cells in vitr

Annexin A5-Functionalized Bimodal Nanoparticles for MRI and Fluorescence Imaging of Atherosclerotic Plaques

Apoptosis and macrophage burden are believed to correlate with atherosclerotic plaque vulnerability and are therefore considered important diagnostic and therapeutic targets for atherosclerosis. These cell types are characterized by the exposure of phosphatidylserine (PS) at their surface. In the present study, we developed and applied a small micellar fluorescent annexin A5-functionalized nanoparticle for noninvasive magnetic resonance imaging (MRI) of PS exposing cells in atherosclerotic lesions. Annexin A5-mediated target-specificity was confirmed with ellipsometry and in vitro binding to apoptotic Jurkat cells. In vivo T(1)-weighted MRI of the abdominal aorta in atherosclerotic ApoE(-/-) mice revealed enhanced uptake of the annexin A5-micelles as compared to control-micelles, which was corroborated with ex vivo near-infrared fluorescence images of excised whole aortas. Confocal laser scanning microscopy (CLSM) demonstrated that the targeted agent was associated with macrophages and apoptotic cells, whereas the nonspecific control agent showed no clear uptake by such cells. In conclusion, the annexin A5-conjugated bimodal micelles displayed potential for noninvasive assessment of cell types that are considered to significantly contribute to plaque instability and therefore may be of great value in the assessment of atherosclerotic lesion phenotyp