Rheology of different hydrocolloids-rice starch blends. Effect of successive heating-cooling cycles

10 pages, 3 figures, 5 tables.-- Available online 25 November 2010.Hydrocolloids are frequently used for modifying starch functionality. In the present study the possible interaction of three different hydrocolloids – guar gum, hydroxypropylmethylcellulose (HPMC) and xanthan gum – with rice starch was explored by determining the pasting, viscoelastic and swelling properties of the rice starch–hydrocolloids mixtures. The impact of successive heating–cooling cycles on the pasting, viscoelasticity and swelling was also determined. Hydrocolloids tested in the range 0.2–0.8% (w/w) significantly modified the pasting, viscoelastic and swelling properties of rice starch–hydrocolloid pastes (8%, w/w) and the extent of the effect was dependent on hydrocolloid concentration. Guar and xanthan gum mixtures with rice starch had the greatest effect on the pasting properties, whereas HPMC mixtures only changed the viscosity during cooling. The starch–hydrocolloids pastes formed weaker gels compared to those of the starch alone. Rheological results suggested the formation of composite network structures with high frequency dependence. Successive multiple-heating cycles allowed the gel to rearrange resulting in altered gel viscoelasticity and release of water soluble compounds that favour phase separation at the highest hydrocolloid level tested.Financial support from University of California-Davis, Ministry of Education and Science, Spanish Research National Council (CSIC) and Spanish Ministerio de Ciencia e Innovación (Project AGL2008-00092/ALI) is gratefully acknowledged. Dr. Rosell thanks the Spanish Ministry of Education and Science for her grant.Peer reviewe

Reference values of vessel diameters, stenosis prevalence, and arterial variations of the lower limb arteries in a male population sample using contrast-enhanced MR angiography

Introduction Morphological characterization of leg arteries is of significant importance to detect vascular remodeling triggered by atherosclerotic changes. We determined reference values of vessel diameters and assessed prevalence of stenosis and arterial variations of the lower limb arteries in a healthy male population sample. Methods Gadolinium-enhanced magnetic resonance angiography at 1.5 Tesla was performed in 756 male participants ( median age = 52 years, range = 21 +/- 82 years) of the population-based Study of Health in Pomerania. Vessel diameters were measured in 9 predefined segments of the pelvic and leg arteries and 95th percentiles were used for upper reference values of means of left and right side arteries. Results Reference values of vascular diameters decreased from proximal to distal arteries: common iliac = 1.18cm;internal iliac = 0.75cm;external iliac = 1.03cm;proximal femoral = 1.02cm;distal femoral = 0.77cm;popliteal = 0.69cm;anterior tibial = 0.42cm;posterior tibial = 0.38cm;fibular = 0.40cm. Body-surface area indexed reference values increased with age in all segments. A number of 53 subjects (7.0%) had at least one stenosis, mainly in the lower leg arteries anterior tibial (n = 28, 3.7%), posterior tibial (n = 18, 2.4%) and fibular (n = 20, 2.6%). The risk of stenosis increased considerably with age (odds ratio = 1.08;p<0.001). The most common arterial variant was type I-A in both legs (n = 620, 82%)

Technical and Clinical Outcome of Talent versus Endurant Endografts for Endovascular Aortic Aneurysm Repair

The technical evolution of endografts for the interventional management of infrarenal abdominal aortic aneurysms (AAA) has allowed a continuous expansion of indications. This study compares the established Talent endograft with its successor, the Endurant endograft, taking individual aortoiliac anatomy into account.From June 2007 to December 2010, 35 patients with AAA were treated with a Talent endograft (33 men) and 36 patients with an Endurant endograft (34 men). Aortoiliac anatomy was evaluated in detail using preinterventional computed tomography angiography. The 30-day outcome of both groups were compared regarding technical and clinical success as well as complications including endoleaks.The Endurant group included more patients with unfavorable anatomy (kinking of pelvic arteries, p = 0.017; shorter proximal neck, p = 0.084). Primary technical success was 91.4% in the Talent group and 100% in the Endurant group (p = 0.115). Type 1 endoleaks occurred in 5.7% of patients in the Talent group and in 2.8% of those in the Endurant group (p = 0.614). Type 3 endoleaks only occurred in the Talent group (2.9% of patients; p = 0.493). Type 2 endoleaks were significantly less common in the Endurant group than in the Talent group (8.3% versus 28.6%; p = 0.035). Rates of major and minor complications were not significantly different between both groups. Primary clinical success was significantly better in the Endurant group (97.2%) than in the Talent group (80.0%) (p = 0.028).Endurant endografts appear to have better technical and clinical outcome in patients with difficult aortoiliac anatomy, significantly reducing the occurrence of type 2 endoleaks

Teil a: Lernvideo Thoraxradiologie

Inhalt: Befundungsalgorithmus; Pneumothorax; Spannungspneumothorax; Pleuraerguss; Silhouettenzeiche

Teil b: Interaktive Vorlesung Thoraxradiologie

Inhalt: Befundungen und Auswertungen von Thoraxaufnahme

Endovascular repair of arterial iliac vessel wall lesions with a self-expandable nitinol stent graft system.

To assess the therapeutic outcome after endovascular repair of iliac arterial lesions (IALs) using a self-expandable Nitinol stent graft system.Between July 2006 and March 2013, 16 patients (13 males, mean age: 68 years) with a self-expandable Nitinol stent graft. A total of 19 lesions were treated: nine true aneurysms, two anastomotic aneurysms, two dissections, one arteriovenous fistula, two type 1B endoleaks after endovascular aneurysm repair, one pseudoaneurysm, and two perforations after angioplasty. Pre-, intra-, and postinterventional imaging studies and the medical records were analyzed for technical and clinical success and postinterventional complications.The primary technical and clinical success rate was 81.3% (13/16 patients) and 75.0% (12/16), respectively. Two patients had technical failure due to persistent type 1A endoleak and another patient due to acute stent graft thrombosis. One patient showed severe stent graft kinking on the first postinterventional day. In two patients, a second intervention was performed. The secondary technical and clinical success rate was 87.5% (14/16) and 93.8% (15/16). The minor complication rate was 6.3% (patient with painful hematoma at the access site). The major complication rate was 6.3% (patient with ipsilateral deep vein thrombosis). During median follow-up of 22.4 months, an infection of the aneurysm sac in one patient and a stent graft thrombosis in another patient were observed.Endovascular repair of various IALs with a self-expandable Nitinol stent graft is safe and effective

Pulmonary emphysema is a predictor of pneumothorax after CT-guided transthoracic pulmonary biopsies of pulmonary nodules.

Pneumothoraces are the most frequently occurring complications of CT-guided percutaneous transthoracic pulmonary biopsies (PTPB). The aim of this study was to evaluate the influence of pre-diagnostic lung emphysema on the incidence and extent of pneumothoraces and to establish a risk stratification for the evaluation of the pre-procedure complication probability.CT-guided PTPB of 100 pre-selected patients (mean age 67.1±12.8 years) were retrospectively enrolled from a single center database of 235 PTPB performed between 2012-2014. Patients were grouped according to pneumothorax appearance directly after PTPB (group I: without pneumothorax, n = 50; group II: with pneumothorax, n = 50). Group II was further divided according to post-interventional treatment (group IIa: chest tube placement, n = 24; group IIb: conservative therapy, n = 26). For each patient pre-diagnostic percentage of emphysema was quantified using CT density analysis. Emphysema stages were compared between groups using bivariate analyses and multinomial logistic regression analyses.Emphysema percentage was significantly associated with the occurrence of post-interventional pneumothorax (p = 0.006). Adjusted for potential confounders (age, gender, lesion size and length of interventional pathway) the study yielded an OR of 1.07 (p = 0.042). Absolute risk of pneumothorax increased from 43.4% at an emphysema rate of 5% to 73.8% at 25%. No differences could be seen in patients with pneumothorax between percentage of emphysema and mode of therapy (p = 0.721).The rate of lung emphysema is proportionally related to the incidence of pneumothorax after CT-guided PTPB and allows pre-interventional risk stratification. There is no association between stage of emphysema and post-interventional requirement of chest tube placement

Successful endovascular repair of an iliac AV fistula in a 49-year-old woman with progressive dyspnea, right leg pain and edematous swelling of the extremity.

<p><b>A</b>) Volume reconstruction (VR) with AV fistula between the right common iliac artery and vein (arrow); note the massive enlargement of the inferior cava vein. <b>B</b>) Angiographic correlation of the finding. <b>C</b>) The control angiogram after stent graft placement reveals a type 1A endoleak with persistent AV fistula (arrow). <b>D</b>) VR 12 months after implantation of a second stent graft (arrows) shows complete occlusion of the AV fistula.</p

Endovascular Repair of Arterial Iliac Vessel Wall Lesions with a Self-Expandable Nitinol Stent Graft System - Table 1

<p>CIA = common iliac artery, IIA = internal iliac artery, EIA = external iliac artery, d = diameter, l = length.</p><p>* = reperfused IIA aneurysm 3 days (patient no. 6) resp. 5 days (patient no. 15) after infrarenal endovascular aneurysm repair.</p

Successful stent graft placement of a ruptured IIA aneurysm in a 77-year-old man with acute abdominal pain in the left lower quadrant.

<p><b>A</b>) Volume reconstruction (VR) shows a large left IIA aneurysm with the irregular boundaries (arrows) indicating a rupture. <b>B</b>) On axial CT scan the true size of the aneurysm is depicted with active bleeding within the thrombosed part and blood surrounding the aneurysm (arrows). <b>C</b>) Selective angiography shows a strong IIA aneurysm (arrow) with major side branches. <b>D</b>) Angiogram after stent graft placement and coiling of aneurysm shows complete exclusion of the aneurysm from blood flow.</p