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Purpose: Highly conformal radiotherapy techniques require precise patient positioning. We report our first experience with a new cast system for fixation of the pelvis during stereotactically guided intensity modulated radiotherapy (IMRT) of the prostate with respect to positioning accuracy of the prostate.Material and Methods: The immobilization device consists of a custom-made wrap-around body cast that extends from the abdomen to the thighs and a separate head mask, both made from Scotchcast, and attaches to a frame for extracranial stereotaxy. Sixteen CT-studies (> or = 25 slices, thickness: 3 mm) of 2 patients who were immobilized for IMRT of prostate tumors were evaluated with respect to set-up accuracy of bony structures and the prostate itself. CT-studies were performed immediately before or after a treatment fraction. Deviations of bony landmarks and anatomical landmarks inside the planning target volume were measured in all 3 dimensions.Results: Mean patient movements of 0.15 +/- 0.3 mm (latero-lateral), 0.9 +/- 1 mm (anterior-posterior), 1 +/- 1 mm (tranversal vectorial error) and < 3 mm slice thickness (craniocaudal) were recorded using bony landmarks and 0.9 +/- 0.9 mm (latero-lateral), 1.8 +/- 1.5 mm (anterior-posterior), 2.2 +/- 1.5 mm (transversal vectorial error) and < 3 mm (craniocaudal) using the confines of, or landmarks within the prostate. Standard deviations of absolute positioning error as an often used metric for positioning accuracy ranged between 0.3 and 1.7 mm in the transversal plane. The worst case transversal vectorial deviation for the prostate was 4.4 mm. Figure 4 summarizes the set-up accuracy of bony landmarks and the prostate.Conclusion: The presented combination of a body cast and head mask system in a rigid stereotactic body frame ensures reliable noninvasive patient fixation for fractionated extracranial stereotactic radiotherapy. It provides precise and reliable positioning of the prostate and meets the requirements for highly conformal radiotherapy such as IMRT. No further improvement of repositioning can be achieved with external immobilization devices since the positioning error of the target relative to the skeleton exceeds the accuracy of the positioning of the skeleton itself. [ABSTRACT FROM AUTHOR]

This paper describes apparatus and methods for measuring uptake of inhaled vapors in the nose and lungs of dogs. The system allows sampling of air from the trachea at specific times during inspiration and expiration without surgical manipulation of the animal, thus allowing repeated studies in the same animal. During exposure, the dogs are anesthetized and cyclic respiratory patterns are maintained by means of an external respirator. A pneumotachograph installed in the exposure line is connected to a respiratory monitoring system that both monitors the dog's respiratory pattern and triggers sampling at specific times in the respiratory cycle. Air sampling, both at the nose and within the trachea, can be done during the entire breathing cycle or during specific portions of it. Vapors are sampled at a point just external to the dog's nose and from within the trachea through a modified endotracheal tube. To develop and demonstrate the system, three beagle dogs were exposed to 2,4-dimethylpentane and 1,3-dioxolane at nominal vapor concentrations of 500 ppm; vapor sampling was triggered for the entire inspiratory and expiratory portions of the breathing cycle during 10-min exposures. After correcting data to account for vapor that desorbed from the nasal passages during exhalation (after initially being absorbed in the nose during inhalation), net nasal uptake of 2,4-dimethylpentane was 28.3%; net nasal uptake of 1,3-dioxolane was 66.6%. Lung uptake was 14.0% for 2,4-dimethylpentane and 2.1% for 1,3-dioxolane. The system was developed for use with dogs, but it can be adapted for use with any animal species that can be intubated with endotracheal vapor sampling tubes. [ABSTRACT FROM PUBLISHER]

The aim of the study was to assess the physiological and antioxidant status before and after a 4 h search and rescue field exercise, with handlers, under warm-weather conditions performing activities compared to a control group of similarly trained dogs at rest. Serum chemistry demonstrated a decrease in serum sodium (Na) and potassium (K) in both exercising and control groups, however only Na was decreased significantly (P < 0.05) after exercise and hematocrits (HCTs) remained unchanged. The exercise group demonstrated significantly decreased serum phosphorus (P) and magnesium (Mg) compared to pre-exercise values, as did the control group (P < 0.025). There was also a significant increase in creatinine kinase concentrations in the exercise groups (P < 0.025). Serum non-esterified fatty acids were increased only in the exercise group after exercise, suggesting fat mobilization to produce energy. The mean total serum antioxidant potential in searching dogs was no different from the pre- and post-exercise values in the control dogs. Serum vitamin E concentrations did not differ between the two groups, with a decreasing trend in both groups. There was a modest decrease in serum uric acid in the control group, while there was a significant rise after exercise in the searching group (P < 0.01). Multiple changes in serum chemistry, HCTs and blood gases were documented in this study, and were similar to those observed after other endurance activities. The lack of hemoconcentration in this field search exercise suggested that even in extreme environmental conditions (heat and humidity), dogs with access to water do not experience significant dehydration or diminished antioxidant status., (Copyright © 2015. Published by Elsevier Ltd.)

Background: Dogs are a unique model for examining the effects of exercise on vitamin D status because of their lack of vitamin D synthesis by UV exposure. In addition, the inflammatory response may be associated with hypovitaminosis D., Objectives: To investigate the effects of several days of endurance exercise on plasma vitamin D (25-(OH)D3, 24,25-(OH)D3 and 1,25(OH)D3) and serum C-reactive protein (CRP) concentrations in stage-stop racing sled dogs., Animals: 12 racing sled dogs and 8 control dogs., Methods: Blood was collected before the race and immediately after racing on days 2 and 8. Plasma vitamin D metabolites and serum CRP concentrations were measured., Results: Racing dogs showed a significant increase in 25(OH)D3 on day 2 (P = .027) and day 8 of the race (P < .001), whereas no increases were observed in control dogs. The plasma concentration of 24,25(OH)D3 showed a significant increase by day 8 (P < .001). There were no significant changes in 1,25(OH) D3 concentrations across all time points and groups. Racing dogs had significantly increased CRP concentrations by day 2 (39.3 ± 30.1 μg/mL; P < .001)., Conclusions and Clinical Importance: Increases in vitamin D metabolites as well as increases in CRP concentrations were observed in racing sled dogs. This finding was contrary to the hypothesis that decreases in vitamin D status in athletes may be related to the acute phase inflammatory response during exercise. In addition, the increased 24,25(OH)D3 concentrations compared to what is observed in other species suggests metabolic variations in dogs that lead to enhanced disposal of vitamin D., (Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.)

The effect of a protective cream was tested in a new tandem repeated irritation test with tandem application of 0.5% sodium lauryl sulphate (SLS) and undiluted toluene. The irritants were applied twice daily for 30 min to the ventral forearms of 20 volunteers. Irritant cutaneous reactions were quantified by a visual score, transepidermal water loss, chromametry and skin capacitance. Concurrent application of SLS/toluene induced stronger reactions than those caused by twice daily application of each irritant on its own. A protective effect of the protective cream was obtained against all treatment combinations and was significant for SLS/SLS (p < or = 0.01) and SLS/ toluene (p < or = 0.05). Our results indicate that the tandem repetitive irritation test has great potential in the evaluation of skin care products to prevent irritant contact dermatitis.

In this article, the results of 3 studies on 2 hand cleansers (products A and B) are analysed. Three different test models (the patch test, the forearm wash test and the use test) are used to obtain information on the skin irritancy of these 2 products. Test reactivity was assessed by clinical scores and bioengineering methods such as corneometry for skin moisture, transepidermal water loss measurements for barrier function and chromametry for erythema. A correlating trend of product A being more aggressive than product B could be confirmed in all 3 studies and was statistically significant in the patch-testing series. Distinction of the results was dependent on the test protocol employed. Models for testing cleansing preparations should be chosen carefully, depending on the hypothesis to be evaluated.

Background: Many surgeons and orthopaedic references recommend that fixation of a disrupted distal tibiofibular syndesmosis be performed with the ankle in dorsiflexion to avoid overtightening and subsequent restriction of ankle dorsiflexion. This recommendation is based in large part on one cadaveric study without clinical correlation. The purpose of the present study was to examine whether overtightening of the syndesmosis limits maximal ankle dorsiflexion., Methods: Nineteen cadaveric ankles were used for the study. Each ankle was tested for the initial range of motion after release of the Achilles tendon proximal to the ankle joint. All capsular and ligamentous structures remained intact. Kirschner wires were placed in the tibia and talus. The angle between the wires with the ankle maximally dorsiflexed was measured before and after syndesmotic compression. Syndesmotic compression was achieved with a 4.5-mm lag screw with the ankle in plantar flexion., Results: There was no difference between the values for maximal dorsiflexion before and after syndesmotic compression., Conclusions: Syndesmotic compression in and of itself does not diminish ankle dorsiflexion in a cadaveric model., Clinical Relevance: Maximal dorsiflexion of the ankle during syndesmotic fixation is not required in order to avoid loss of dorsiflexion. It is likely that the most important aspect of syndesmotic fixation is anatomic reduction of the syndesmosis and that the degree of ankle dorsiflexion during fixation is not important.

The objective of this study was to investigate MRI methods for monitoring focused ultrasound surgery (FUS) of breast tumors. To this end, the mammary glands of sheep were used as tissue model. The tissue was treated in vivo with numerous single sonications which covered extended target volumes by employing a scanning technique. The ultrasound focus position was controlled by online temperature mapping based on the temperature dependence of the relaxation time T(1). This approach proved to be reliable and offers thus an alternative to proton resonance frequency methods, whose application is hampered in fatty tissues. FUS-induced tissue changes were visible on T(2)- as well as on pre- and post-contrast T(1)-weighted images. According to our initial experience, noninvasive MRI-guided FUS of breast tumors is feasible.

Purpose: Highly conformal radiotherapy techniques require precise patient positioning. We report our first experience with a new cast system for fixation of the pelvis during stereotactically guided intensity modulated radiotherapy (IMRT) of the prostate with respect to positioning accuracy of the prostate., Material and Methods: The immobilization device consists of a custom-made wrap-around body cast that extends from the abdomen to the thighs and a separate head mask, both made from Scotchcast, and attaches to a frame for extracranial stereotaxy. Sixteen CT-studies (> or = 25 slices, thickness: 3 mm) of 2 patients who were immobilized for IMRT of prostate tumors were evaluated with respect to set-up accuracy of bony structures and the prostate itself. CT-studies were performed immediately before or after a treatment fraction. Deviations of bony landmarks and anatomical landmarks inside the planning target volume were measured in all 3 dimensions., Results: Mean patient movements of 0.15 +/- 0.3 mm (latero-lateral), 0.9 +/- 1 mm (anterior-posterior), 1 +/- 1 mm (tranversal vectorial error) and < 3 mm slice thickness (craniocaudal) were recorded using bony landmarks and 0.9 +/- 0.9 mm (latero-lateral), 1.8 +/- 1.5 mm (anterior-posterior), 2.2 +/- 1.5 mm (transversal vectorial error) and < 3 mm (craniocaudal) using the confines of, or landmarks within the prostate. Standard deviations of absolute positioning error as an often used metric for positioning accuracy ranged between 0.3 and 1.7 mm in the transversal plane. The worst case transversal vectorial deviation for the prostate was 4.4 mm. Figure 4 summarizes the set-up accuracy of bony landmarks and the prostate., Conclusion: The presented combination of a body cast and head mask system in a rigid stereotactic body frame ensures reliable noninvasive patient fixation for fractionated extracranial stereotactic radiotherapy. It provides precise and reliable positioning of the prostate and meets the requirements for highly conformal radiotherapy such as IMRT. No further improvement of repositioning can be achieved with external immobilization devices since the positioning error of the target relative to the skeleton exceeds the accuracy of the positioning of the skeleton itself.

The aim of the study was to control the number of inertial cavitation bubbles in the focal area of an electromagnetic lithotripter in water independently of peak intensity, averaged intensity or pressure waveform. To achieve this, the shockwave pulses were applied in double pulse sequences, which were administered at a fixed pulse repetition frequency (PRF) of 0.33 Hz. The two pulses of a double pulse were separated by a variable short pulse separation time (PST) ranging from 200 micros to 1500 ms. The number and size of the cavitation bubbles were monitored by scattered laser light and stroboscopic photographs. We found that the number of inertial cavitation bubbles as a measure of cavitation dose was substantially influenced by variation of the PST, while the pressure pulse waveform, averaged acoustic intensity and bubble size were kept constant. The second pulse of each double pulse generated more cavitation bubbles than the first. At 14 kV capacitor voltage, the total number of cavitation bubbles generated by the double pulses increased with shorter PST down to approximately 400 micros, the cavitation lifespan. The results can be explained by cavitation nuclei generated by the violently imploding inertial cavitation bubbles. This method of pulse administration and cavitation monitoring could be useful to establish a cavitation dose-effect relationship independently of other acoustic parameters.

To determine whether the accepted principles of management of open tibia fractures apply to children, 40 consecutive open fractures of the tibial shaft in skeletally immature patients were retrospectively reviewed. Attempts were made to evaluate the functional and social impact of open tibia fractures in children. All open fractures were initially treated by rapid irrigation and debridement which was repeated every 48 hours until soft tissues stabilized. The average age was 10.1 years and average follow up was 26 months (range: 18 to 84). There were 16 grade I, 10 grade II, and 14 grade III open fractures. The grade III fractures were further subdivided into 6 grade IIIA, 7 grade IIIB, and 1 grade IIIC. The average time to union was 7.5 and 11.0 weeks in the grade I and II fractures respectively, with no infections and no delayed unions. In grade III fractures, the average time to union was 15 weeks, with 1 infection and 3 delayed unions. Bone grafting using autogenous iliac crest was performed on 2 patients. The children surveyed missed an average of 4.1 months of school and 33% had to repeat a year. Twenty-five percent of the children complained of nightmares involving the events of the accident. Chronic pain despite solid union was found in 30% of patients. Forty percent of those surveyed (7 grade III fractures) complained of a limp. The low incidence of soft tissue complications and infections in the study population supports applying in children the same basic soft tissue management principles of open fracture treatment as used in adults. While bone stabilization options are limited in children, the rate of successful union without adjunctive bone grafting is much higher than that of adults treated under similar protocols. Routine early iliac crest bone grafting is unnecessary. The prevalence of gait abnormality despite fracture union should be taken into account during the patient's rehabilitation. The extensive time missed from school and resulting scholastic setback should not be underestimated.

A microspray nozzle has been developed for the localized administration of solutions or suspensions to discrete pulmonary airway regions via bronchoscopy. Toxicants or tracer particles can be administered to single or multiple, specific lung airway segments. This permits studies of local-airway, whole-lung, and systemic responses to inhaled materials. The nozzle is fabricated by ultra-precision machining, has an overall length of 1 mm, and a diameter small enough to fit in the end of a 1.1-mm inner diameter, 1.2-mm outer diameter catheter. In vitro studies demonstrated the delivery efficiency for 99mTc solutions (98 +/- 1% SD) and for suspensions of 99mTc sulfur colloid or 3-mum 85Sr-labeled microspheres (55 +/- 15%). Photographic and gamma camera images of material deposited in the airways of Beagle dogs demonstrated in vivo that the deposition patterns are compact and uniform. The technique may also have therapeutic medical applications.