Experimental discrimination of ion stopping models near the Bragg peak in highly ionized matter.

The energy deposition of ions in dense plasmas is a key process in inertial confinement fusion that determines the α-particle heating expected to trigger a burn wave in the hydrogen pellet and resulting in high thermonuclear gain. However, measurements of ion stopping in plasmas are scarce and mostly restricted to high ion velocities where theory agrees with the data. Here, we report experimental data at low projectile velocities near the Bragg peak, where the stopping force reaches its maximum. This parameter range features the largest theoretical uncertainties and conclusive data are missing until today. The precision of our measurements, combined with a reliable knowledge of the plasma parameters, allows to disprove several standard models for the stopping power for beam velocities typically encountered in inertial fusion. On the other hand, our data support theories that include a detailed treatment of strong ion-electron collisions.

Models of short bowel syndrome in pigs: a technical review.

BACKGROUND: Short bowel syndrome (SBS) is still a life-threatening disease in both children and adults. Although the therapeutic options are improving, challenges still remain, and to overcome these challenges is a major focus of SBS research today. In order to simulate anatomical and physiological conditions similar to those in humans for research, porcine models of SBS are often used. Various approaches for generating SBS models have been described in the literature. METHODS/RESULTS: In this work, we present a review of different types of porcine models of SBS and outline the differences between those models regarding types of animals, surgical procedures, monitoring, and methods of assessment. CONCLUSION: The aim of this study was to select the most suitable SBS model regarding the purpose of the research.

Practice of dilatation after surgical correction in anorectal malformations.

BACKGROUND: In order to prevent stricture of the neoanus after surgical correction, regular dilatation is recommended. There is a lack of knowledge about the performance of anal dilatation and the occurrence of pain. The aim of our investigation was to describe the practice of dilatation and to identify possible risk factors for painful procedures. METHODS: Congenital Uro-Rectal Malformations Network is a German interdisciplinary multicenter research network. With standard questionnaires, physicians interviewed 243 patients and/or their parents at home, additional 103 patients born since 2009 were assessed through their treating physicians. RESULTS: In total, 88 % of the patients received dilatations. Treatment lasted for 7 months in median (range 1-156 months), until the age of 13 months (range 1-171 months). In 69 % painful dilatation was reported; without a significant differences in age or gender. In 32 % bleeding was reported. In 30 % at least one dilatation was performed under general anesthesia. In 11 % some kind of analgesia was used. Type of fistula, dilatations lasting longer than 10 months and Hegar size above 15 were relevant factors for experience of pain. There were about 16 % postoperative strictures of the neoanus, without reported differences in dilatation procedures; but there was a relation to type of malformation. CONCLUSION: Considering the high number of painful treatments, predictors for painful dilatations should be further clarified through standardized documentation and prospective evaluation in order to improve follow-up.

Current practice and future perspectives in the treatment of short bowel syndrome in children--a systematic review.

PURPOSE: Short bowel syndrome (SBS) is a malabsorption disorder of the intestine, which leads to an inadequate alimentary supply. A number of therapeutic approaches are already in use, but research advances may provide new options in the future. The purpose of this paper was to provide an overview of the established therapeutic approaches together with a discussion of the future perspectives in the treatment of patients with SBS. We review those studies dealing with the treatment of SBS patients and discuss both surgical and non-surgical approaches together with tissue engineering. METHODS: A systemic review of Medline-cited studies dealing with current practice and future perspectives in the treatment of short bowel in children was performed. RESULTS: Surgical approaches, non-surgical approaches, and tissue engineering which was used in the treatment of SBS were analyzed. Among the surgical approaches, the bowel lengthening procedures and small bowel transplantation are prevalent. Stimulants are most important concerning non-surgical approaches. Tissue engineering seems to be more experimental and was also evaluated. CONCLUSION: The treatment of SBS patients remains very complex. It is eminent to find the best therapeutic option for each patient and to individualize and modify the different possible types of applied techniques frequently.

Revision surgery in pectus excavatum after failure of Nuss technique.

A 17-year-old female had undergone two failed pectus excavatum repairs using the Nuss technique. Each time the bar had shifted, one time displacing the heart. Revision surgery was carried out using the Erlangen technique, which proved to be a safe and successful method to remove the displaced bar and correct the pectus excavatum.

Bradykinin in ischemia-reperfusion injury of the rat lung.

Recent studies described possibilities to reduce lung damage after intestinal ischemia by application of a selective bradykinin-2 receptor antagonist (HOE 140). In contrast, it has been shown that the preischemic application of bradykinin (BK) reduced ischemic damage of the myocardium. In the present study, to evaluate the effects of BK and HOE 140 in lung ischemia-reperfusion injury we used a standardized in vivo ischemia-reperfusion model of the right rat lung. Ischemia of 60 min was induced by cross-clamping of the right hilus followed by 120 min of reperfusion. During reperfusion, the left hilus was ligated. In Group 1 (n=5), the animals were sham operated without induction of ischemia under ligation of the left lung hilus. Group 2 (n=5) was operated as described, Group 3 (n=5) received 100 microg bradykinin (BK) before reperfusion, Group 4 (n=5) was given a B2-agonist before reperfusion, and Group 5 (n=5) was given 100 microg HOE140/kg body weight before reperfusion. Blood pressure and arterial oxygenation were monitored. As a marker of endothelial damage, angiotensin-converting-enzyme activity (ACE) in serum and RT-PCR of ACE and angiotensin-2 in lung tissue were determined in all groups. Two of the HOE140-treated animals died within 30 min of reperfusion. During reperfusion, significantly higher PaO2 values (P<0.01) have been observed in BK treated animals of Group 3 (214+/-22 mmHg) and sham operated controls of Group 1 (233+/-26 mmHg) compared with Groups 2 (132+/-13 mmHg) and Group 5 (125+/-50 mmHg; P<0.01). Serum ACE activity after reperfusion was significantly lower in Group 1 (3.5+/-0.5 IU/l), Group 3 (3.8+/-1.1 IU/l), and Group 4 (2.2+/-0.5 IU/l; P<0.05) vs. Group 2 (4.8+/-0.9 IU/l), whereas Group 5 (6.2+/-5.4 IU/l) did not differ from Group 2. mRNA expressions of ACE was lower in Group 1 and Group 3 compared with Group 2 (P<0.01). AT-2 mRNA expression did not show any differences between the investigated groups. A significantly lower ACE activity and expression and a significantly higher oxygenation after BK application in Group 3 strongly suggest a positive influence of bradykinin on ischemic preconditioning of the pulmonary endothelium. Positive effects of application of bradykinin-receptor antagonists could not be proved in this study.