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Determining the brain perfusion is an important task for diagnosis of vascular diseases such as occlusions and intracerebral haemorrhage. Even after successful diagnosis, there is a high risk of restenosis or rebleeding such that patients need intense attention in the days after treatment. Within this work, we present a diagnostic tomographic imager that allows access to brain perfusion quantitatively in short intervals. The device is based on the magnetic particle imaging technology and is designed for human scale. It is highly sensitive and allows the detection of an iron concentration of 263 pmol Fe  ml −1 , which is one of the lowest iron concentrations imaged by MPI so far. The imager is self-shielded and can be used in unshielded environments such as intensive care units. In combination with the low technical requirements this opens up a variety of medical applications and would allow monitoring of stroke on intensive care units. Magnetic particle imaging (MPI) has been applied to various pre-clinical settings, including detection of ischemic stroke in mice. Translation of MPI to a clinical setting has been obstacled by the lack of a device with sufficient bore size and, at the same time, reasonable technical requirements. Here the authors present a human-sized MPI device with low technical requirements designed for detection of brain ischemia.

Background: Repetitive or sustained elevated shoulder postures have been identified as a significant risk factor for occupationally related shoulder musculoskeletal disorders. Construction workers exposed to routine overhead work have high rates of shoulder pain that frequently progresses to functional loss and disability. Exercise interventions have potential for slowing this progression. Aims: To evaluate a therapeutic exercise programme intended to reduce pain and improve shoulder function. Methods: Construction worker volunteers were screened by history and clinical examination to test for inclusion/exclusion criteria consistent with shoulder pain and impingement syndrome. Sixty seven male symptomatic workers (mean age 49) were randomised into a treatment intervention group (n = 34) and a control group (n = 33); asymptomatic subjects (n = 25) participated as an additional control group. Subjects in the intervention group were instructed in a standardised eight week home exercise programme of five shoulder stretching and strengthening exercises. Subjects in the control groups received no intervention. Subjects returned after 8–12 weeks for follow up testing. Results: The intervention group showed significantly greater improvements in the Shoulder Rating Questionnaire (SRQ) score and shoulder satisfaction score than the control groups. Average post-test SRQ scores for the exercise group remained below levels for asymptomatic workers. Intervention subjects also reported significantly greater reductions in pain and disability than controls. Conclusions: Results suggest a home exercise programme can be effective in reducing symptoms and improving function in construction workers with shoulder pain.

Background and Purpose. Treatment of patients with impingement symptoms commonly includes exercises intended to restore “normal” movement patterns. Evidence that indicates the existence of abnormal patterns in people with shoulder pain is limited. The purpose of this investigation was to analyze glenohumeral and scapulothoracic kinematics and associated scapulothoracic muscle activity in a group of subjects with symptoms of shoulder impingement relative to a group of subjects without symptoms of shoulder impingement matched for occupational exposure to overhead work. Subjects. Fifty-two subjects were recruited from a population of construction workers with routine exposure to overhead work. Methods. Surface electromyographic data were collected from the upper and lower parts of the trapezius muscle and from the serratus anterior muscle. Electromagnetic sensors simultaneously tracked 3-dimensional motion of the trunk, scapula, and humerus during humeral elevation in the scapular plane in 3 hand-held load conditions: (1) no load, (2) 2.3-kg load, and (3) 4.6-kg load. An analysis of variance model was used to test for group and load effects for 3 phases of motion (31°–60°, 61°–90°, and 91°–120°). Results. Relative to the group without impingement, the group with impingement showed decreased scapular upward rotation at the end of the first of the 3 phases of interest, increased anterior tipping at the end of the third phase of interest, and increased scapular medial rotation under the load conditions. At the same time, upper and lower trapezius muscle electromyographic activity increased in the group with impingement as compared with the group without impingement in the final 2 phases, although the upper trapezius muscle changes were apparent only during the 4.6-kg load condition. The serratus anterior muscle demonstrated decreased activity in the group with impingement across all loads and phases. Conclusion and Discussion. Scapular tipping (rotation about a medial to lateral axis) and serratus anterior muscle function are important to consider in the rehabilitation of patients with symptoms of shoulder impingement related to occupational exposure to overhead work.

Single- and multi-quantum well (QW) structures of Ga(AsBi)/GaAs with up to 10% Bi were grown by molecular beam epitaxy (MBE) at 300–330°C substrate temperature. The photoluminesce measurements of QW structures demonstrated room temperature emission up to wavelengths of ∼1.43 μm. In the structures obtained using a combined growth approach – an active layer with three QWs with ∼6% Bi was grown by MBE, whereas (AlGa)As claddings were grown by the metal organic vapour phase epitaxy technique – room temperature lasing at 1060 nm was documented.

We have studied the effects of carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) on tumor angiogenesis in murine ductal mammary adenocarcinomas. We crossed transgenic mice with whey acidic protein promoter-driven large T-antigen expression (WAP-T mice) with oncogene-induced mammary carcinogenesis with CEACAM1null mice, and with Tie2-Ceacam1 transgenics, in which the Tie2 promoter drives endothelial overexpression of CEACAM1 (WAP-T × CEACAM1 endo+ mice), and analyzed tumor vascularization, angiogenesis and vessel maturation in these mice. Using flat-panel volume computed tomography (fpVCT) and histology, we found that WAP-T × CEACAM1 endo+ mice exhibited enhanced tumoral vascularization owing to CEACAM1 + vessels in the tumor periphery, and increased intratumoral angiogenesis compared with controls. In contrast, vascularization of CEACAM1null/WAP-T-derived tumors was poor, and tumor vessels were dilated, leaky and showed poor pericyte coverage. Consequently, the tumoral vasculature could not be visualized in CEACAM1null/WAP-T mice by fpVCT, and we observed poor organization of the perivascular extracellular matrix (ECM), accompanied by the accumulation of collagen IV-degrading matrix metalloproteinase 9 + (MMP9 + ) leukocytes and stromal cells. Vascular instability and alterations in ECM structure were accompanied by a significant increase in pulmonary metastases in CEACAM1null/WAP-T mice, whereas only occasional metastases were observed in CEACAM1 + hosts. In CEACAM1 + hosts, intratumoral vessels did not express CEACAM1, but they were intact, extensively covered with pericytes and framed by a well-organized perivascular ECM. MMP9 + accessory cells were largely absent. Orthotopic transplantation of primary WAP-T- and CEACAM1null/WAP-T tumors into all three mouse lines confirmed that a CEACAM1 + host environment is a prerequisite for productive angiogenic remodeling of the tumor microenvironment. Hence, CEACAM1 expression in the tumor periphery determines the vascular phenotype in a tumor, whereas systemic absence of CEACAM1 interferes with the formation of an organized tumor matrix and intratumoral vessel maturation.

Study design: Case series; nonparametric repeated-measures analysis of variance. Objective: To compare and contrast three-dimensional shoulder kinematics during frequently utilized upper extremity weight-bearing activities (standing depression lifts used in brace walking, weight-relief raises, transfers) and postures (sitting rest, standing in a frame) in spinal cord injury (SCI). Setting: Movement Analysis Laboratory, Department of Physical Therapy, Ithaca College, Rochester, NY, USA. Methods: Three female and two male subjects (39.2±6.1 years old) at least 12 months post-SCI (14.6±6.7 years old), SCI distal to T2 and with an ASIA score of A. The Flock of Birds magnetic tracking device was used to measure three-dimensional positions of the scapula, humerus and thorax during various activities. Results: Standing in a frame resulted in significantly less scapular anterior tilt (AT) and greater glenohumeral external rotation (GHER) than standing depression lifts and weight-relief raises. Conclusions: Standing frame posture offers the most favorable shoulder joint positions (less scapular AT and greater GHER) when compared to sitting rest posture, weight-relief raises, transfers and standing depression lifts. Knowledge of kinematic patterns associated with each activity is an essential first step to understanding the potential impact on shoulder health. Choosing specific activities or modifying techniques within functional activities that promote favorable shoulder positions may preserve long-term shoulder health. Sponsorship: National Institute of Health (R15HD41379-01) and the Spinal Cord Research Foundation (2251-01).

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

Hallux valgus is a progressive foot deformity characterized by a lateral deviation of the hallux with corresponding medial deviation of the first metatarsal. Late-stage changes may render the hallux painful and without functional utility, leading to impaired gait. Various environmental, genetic, and anatomical predispositions have been suggested, but the exact cause of hallux valgus is unknown. Evidence indicates that conservative intervention for hallux valgus provides relief from symptoms but does not reverse deformity. Part 1 of this perspective article reviews the literature describing the anatomy, pathomechanics, and etiology of hallux valgus. Part 2 expands on the biomechanical initiators of hallux valgus attributed to the first metatarsal. Theory is advanced that collapse of the arch with vertical orientation (tilt) of the first metatarsal axis initiates deformity. To counteract the progression of hallux valgus, we use theory to discuss a possible mechanism by which foot orthoses can bolster the arch and reorient the first metatarsal axis horizontally.

Background and Purpose. People with idiopathic loss of shoulder range of motion (ROM) have difficulty completing activities of daily living. This investigation was performed to determine the association between active glenohumeral ROM and function and to develop a multiple regression equation to explain variation in function in people with idiopathic loss of shoulder motion. Subjects and Methods. This was a comparative study of 21 subjects (18 female, 3 male), using measurements of shoulder kinematics and administration of the Shoulder Rating Questionnaire (SRQ). Electromagnetic tracking sensors monitored the 3-dimensional position of the scapula and humerus throughout active shoulder motions. Correlations were performed between the active ROMs of interest and various demographic factors and the SRQ. A multiple regression equation was generated. Results. A multiple regression equation including scapular-plane abduction, external rotation at the side, external rotation at 90 degrees of abduction, and weight explained 69% of the variation in the SRQ scores. Discussion and Conclusion. The results suggest that active ROM can be used to predict function in people with idiopathic loss of shoulder ROM.

Although not well understood, foot kinematics are changed with hallux valgus. The purpose of this study was to examine tarsal kinematics in women with hallux valgus deformity. A prospective, cross-sectional design was used. Twenty women with (n=10) and without (n=10) deformity participated. Data were acquired with the use of a magnetic resonance scanner. Participants were posed standing to simulate gait, with images reconstructed into virtual bone datasets. Measures taken described foot posture (hallux angle, intermetatarsal angle, arch angle). With the use of additional computer processes, the image sequence was then registered across gait conditions to compute relative tarsal position angles, first-ray angles, and helical axis parameters decomposed into X, Y, and Z components. An analysis of variance model compared kinematics between groups and across conditions. Multiple regression analysis assessed the relationship of arch angle, navicular position, and inclination of the first-ray axis. Both the hallux and intermetatarsal angles were larger with deformity; arch angle was not different between groups. The calcaneus was everted by ≥6.6 degrees, and the first ray adducted (F=44.17) by ≥9.3 degrees across conditions with deformity. There was an interaction (F=5.06) for the first-ray axis. Follow-up comparisons detected increased inclination of the first-ray axis over middle stance compared with late stance in the group with deformity. Gait was simulated, kinetics were not measured, and sample size was small. There were group differences. Eversion of the calcaneus and adduction of the first ray were increased, and the first-ray axis was inclined 24 degrees over middle stance in women with deformity compared with 6 degrees in control participants. Results may identify risk factors of hallux valgus and inform nonoperative treatment (orthoses, exercise) strategies.