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Increased Thickness (increased + thickness)
Selected AbstractsIncreased thickness of the arterial intima-media detected by ultrasonography in patients with rheumatoid arthritisARTHRITIS & RHEUMATISM, Issue 6 2002Yasuro Kumeda Objective To determine whether arterial wall thickening is advanced in rheumatoid arthritis (RA) patients compared with healthy controls by measuring the intima-media thickness (IMT) of the common carotid and femoral arteries, and to evaluate the factors associated with arterial IMT in patients with RA. Methods We studied 138 RA patients and 94 healthy controls (matched for age, sex, and other major risk factors for atherosclerosis). IMT was measured on digitized still images of the common carotid and femoral arteries obtained by high-resolution ultrasonography (10-MHz in-line Sectascanner). Laboratory variables relevant to RA activity were measured by routine methods. The degree of RA progression was assessed by scoring (Larsen method) metacarpophalangeal (MCP) joints on hand radiographs. Activities of daily living were determined by a modified Health Assessment Questionnaire (M-HAQ) score, and physical activity levels were assessed by ultrasound measurement of the calcaneus (expressed as the osteo-sono assessment index [OSI] Z score). Results Common carotid and femoral artery IMTs were significantly higher (P < 0.05) in RA patients (mean ± SD 0.641 ± 0.127 and 0.632 ± 0.125 mm, respectively) compared with controls (0.576 ± 0.115 and 0.593 ± 0.141 mm, respectively). Multiple regression analysis revealed a significant association between RA and the common carotid artery IMT. Moreover, the common carotid artery IMT in RA patients was positively associated with disease duration, the MCP joint Larsen score, and the M-HAQ score, and was negatively associated with the calcaneus OSI Z score. No significant association was found between corticosteroid treatment and common carotid artery IMT. Conclusion RA patients exhibited greater thickness of the common carotid and femoral arteries than healthy controls. The duration and severity of RA and decreased activities of daily living, but not corticosteroid treatment, were independently associated with the increased arterial wall thickness. [source] Radiological interpretation of the navicular boneEQUINE VETERINARY EDUCATION, Issue 5 2008S. Dyson Summary Acquisition of a sufficient number of high quality radiographic views is an essential prerequisite to accurate radiological interpretation of the navicular bone. This requires appropriate preparation of the foot, careful attention to limb position and to both centring and direction of the x-ray beam, according to hoof capsule conformation. Artefacts are easily created. Potentially significant radiological abnormalities include: entheseiophytes at the proximomedial and proximolateral aspect of the bone; proximal or distal extension of the flexor border of the bone, distal border fragments, 8 or more large and variably shaped distal border radiolucent zones; discrete radiolucent areas in the spongiosa with or without detectable communication with the flexor cortex; new bone at the sagittal ridge; increased thickness of the flexor cortex; sclerosis of the spongiosa; and a bipartite bone. [source] MR imaging findings of small bowel hemorrhage: Two cases of mural involvement and one of perimuralJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 5 2009Polytimi Leonardou MD Abstract Purpose To demonstrate the MR appearance of small bowel wall hemorrhage. Materials and Methods A search was performed of the clinical information system (CIS) and the abdominal MRI databases of our institution for patients diagnosed with bowel hemorrhage on MRI between January 1, 2000, and July 31, 2008. All patients were imaged using a protocol that included noncontrast T1- and T2-weighted images and postgadolinium gradient echo images. Results Two male patients, 44 and 55 years of age, were identified with small bowel mural hemorrhage, one in the duodenum and one in the jejunum. A third patient, a 66-year-old man, was identified with perimural hematoma. The following imaging features were observed: for mural hemorrhage, mural-based increased signal intensity (SI) in the bowel wall on fat suppressed T1-weighted images, variable increased SI on T2-weighted images and no appreciable enhancement on the postcontrast T1-weighted image; perimural hemorrhage exhibited normal thickness low SI wall on T2-weighted single shot images, with ill-defined material surrounding the bowel. SI features of this material, was similar to mural-based abnormality. Conclusion In two patients with small bowel wall hemorrhage, the wall showed increased thickness with increased SI on noncontrast T1-weighted images and lack of enhancement on postgadolinium images. Perimural hematoma showed an intact normal thickness wall that was low SI on T2 with surrounding material that was high SI on noncontrast T1-weighted images and did not enhance. J. Magn. Reson. Imaging 2009;29:1185,1189. © 2009 Wiley-Liss, Inc. [source] Improved Dielectric Properties of Bi1.5Zn1.0Nb1.5O7/(111)-Oriented Ba0.6Sr0.4TiO3 Bilayered Films for Tunable Microwave ApplicationsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 5 2010Lihui Yang Bi1.5Zn1.0Nb1.5O7/(111)-oriented Ba0.6Sr0.4TiO3 [BZN/BST (111)] bilayered films (,500-nm-thick) have been prepared on Pt/TiOx/SiO2/Si substrates by RF-magnetron sputtering. Experimental results suggested that the BZN layer has played a positive role in improving the dielectric properties of the films. With the increased thickness of BZN, the dielectric loss was significantly lowered, accompanied with a tolerable reduction of tunability. The thickness effect was discussed with a series connection model of multilayered capacitors, and the calculated permittivity was obtained. At 400 kV/cm, moderate tunability of 50.55%, low dielectric loss of 0.0108, and the largest figure of merit of 46.8 can be achieved for BZN (50 nm)/BST(450 nm) bilayered films. [source] Polypyrrole Thin Films Formed by Admicellar Polymerization Support the Osteogenic Differentiation of Mesenchymal Stem CellsMACROMOLECULAR BIOSCIENCE, Issue 8 2004Harold Castano Abstract Summary: The objective of this study was to evaluate the attachment, proliferation, and differentiation of rat mesenchymal stem cells (MSC) toward the osteoblastic phenotype seeded on polypyrrole (PPy) thin films made by admicellar polymerization. Three different concentrations of pyrrole (Py) monomer (20, 35, and 50,×,10,3M) were used with the PPy films deposited on tissue culture polystyrene dishes (TCP). Regular TCP dishes and PPy polymerized on TCP by chemical polymerization without surfactant using 5,×,10,3M Py, were used as controls. Rat MSC were seeded on these surfaces and cultured for up to 20 d in osteogenic media. Surface topography was characterized by atomic force microscopy, X-ray photoelectron spectroscopy, and static contact angle. Cell attachment, proliferation, alkaline phosphatase (ALP) activity, and calcium content were measured to evaluate the ability of MSC to adhere and differentiate on PPy-coated TCP. Increased monomer concentrations resulted in PPy films of increased thickness and surface roughness. PPy films generated by different monomer concentrations induced drastically different cellular events. A wide spectrum of cell attachment characteristics (from excellent cell attachment to the complete inability to adhere) were obtained by varying the monomer concentration from 20 m to 50,×,10,3M. In particular the 20,×,10,3M PPy thin films demonstrated superior induction of MSC osteogenicity, which was comparable to standard TCP dishes, unlike PPy films of similar thickness prepared by chemical polymerization without surfactant. Adhesion of mesenchymal stem cells on tissue culture plates (TCP) coated with polypyrrole thin films made by admicellar polymerization. [source] Leaf Epidermal Hydathodes and the Ecophysiological Consequences of Foliar Water Uptake in Species of Crassula from the Namib Desert in Southern AfricaPLANT BIOLOGY, Issue 2 2000C. E. Martin Abstract: Epidermal hydathodes were found on leaves of 46 of 48 species of Crassula collected from the Namib Desert in southern Africa. The possibility that these structures might allow the absorption of surface water was investigated in 27 species (including subspecies). The presence of hydathodes on leaf epidermi correlated, in most cases, with increases in leaf thickness and enhanced rates of nocturnal, and sometimes diurnal, CO2 uptake following wetting of the leaves during the night. The precise nature of these responses varied depending on the species. In addition, wetting only the older leaves on the lower portion of the shoot of C. tetragona ssp. acutifolia not only resulted in increased thickness of these leaves, but also effected an increase in leaf thickness and stimulation of CO2 uptake rates in the distal, younger portion of the shoot that was not wetted. Overall, foliar hydathodes were implicated in the absorption of surface water in many species of Crassula such that the ecophysiology of these desert succulents was positively affected. Although rainfall in the Namib Desert is infrequent, surface wetting of the leaves is a more common occurrence as a result of nighttime dew or fog deposition. Presumably, species with hydathodes benefit directly from this source of moisture. These findings have important implications in understanding a relatively unexplored adaptation of some xerophytes to an extremely arid environment. [source] Frequency of atrial septal aneurysm in patients with recent stroke: Preliminary results from a multicenter studyCLINICAL CARDIOLOGY, Issue 4 2001Michele Aquilina M.D. Abstract Background: The role of atrial septal aneurysm (ASA) as a risk factor for cerebral ischemia of unknown etiology is controversial. Recent studies have found an association between ASA and focal ischemic events, while results from other studies suggest a low incidence of embolism in patients with ASA. Hypothesis: The present study was designed to evaluate the frequency of ASA, a minor cardioembolic source, in patients with a recent stroke presenting with normal carotid arteries. Methods: In all, 394 patients with cerebral ischemic stroke were referred to our institutions. Patients underwent transthracic and transesophageal echocardiography and carotid artery ultrasound examination. The study population included 215 patients without significant arterial disease. Frequency and morphologic characteristics of ASA were evaluated. Results: Transthoracic examination showed ASA in 39 patients (18%), while transesophageal echocardiography showed ASA in 61 patients (28%). A patent foramen ovale was found in 47 patients (21.8%) and was associated with ASA in 40 patients (65.5%). We observed an increased thickness of the aneurysmatic wall (3.80 ± 1.7 mm) in all patients with ASA. Conclusions: The present study confirms the relationship between ASA and stroke in patients with normal carotid arteries. The most common abnormality associated with ASA was patent foramen ovale. We suggest that patients who have a stroke in the absence of significant carotid disease undergo transesophageal echocardiography to identify possible underlying septal abnormalities. [source] |