Directed migration by contact guidance is a poorly understood yet vital phenomenon, particularly for carcinoma cell invasion on aligned collagen fibres. We demonstrate that for single cells, aligned architectures providing contact guidance cues induce constrained focal adhesion maturation and associated F-actin alignment, consequently orchestrating anisotropic traction stresses that drive cell orientation and directional migration. Consistent with this understanding, relaxing spatial constraints to adhesion maturation either through reduction in substrate alignment density or reduction in adhesion size diminishes the contact guidance response. While such interactions allow single mesenchymal-like cells to spontaneously ‘sense' and follow topographic alignment, intercellular interactions within epithelial clusters temper anisotropic cell–substratum forces, resulting in substantially lower directional response. Overall, these results point to the control of contact guidance by a balance of cell–substratum and cell–cell interactions, modulated by cell phenotype-specific cytoskeletal arrangements. Thus, our findings elucidate how phenotypically diverse cells perceive ECM alignment at the molecular level.

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The diagnosis of Mycobacterium ulcerans infection is hampered by the slow growth of the bacterium in culture, resulting in a delay of several months before a specific diagnosis can be obtained. In addition, M. ulcerans cannot be isolated from water even when there is convincing epidemiological evidence implicating this as the source of infection. The aim of the present study was to develop a PCR assay to circumvent the problems of delayed diagnosis and insensitivity of standard bacterial culture for M. ulcerans. For the PCR, we isolated an M. ulcerans-specific DNA fragment, 1,109 bp long, which is repeated at least 50 times throughout the genome. Use of this sequence as a target for PCR allowed us to detect as few as 2 molecules of genomic DNA in vitro. The PCR was used to detect M. ulcerans DNA in fresh tissue and paraffin-embedded sections from all seven patients with culture-confirmed cases of infection.

The objective was to identify the usefulness of heparin level by anti-factor Xa (anti-Xa) assay vs activated partial thromboplastin time (PTT) or activated clotting time (ACT) in neonates undergoing extracorporeal membrane oxygenation (ECMO). A retrospective record review of 21 patients in the neonatal intensive care unit (mean ECMO initiation age, 2 days; range, 0-4 days; male/female ratio, 1:1) undergoing ECMO from 2006 to 2008 was performed. Linear regression correlations between anti-Xa, PTT, and ACT were determined by extrapolating PTT and ACT therapeutic ranges that corresponded with the ECMO heparin target range of 0.3 to 0.6 U/mL. Pearson correlation coefficients between heparin levels and PTT (-0.903 to 0.984), PTT less than 40 seconds after correction using PTT-heparinase (-0.903 to 1.000), and ACT (-0.951 to 0.891) in this patient population were widely variable. Inconsistency of PTT and ACT therapeutic ranges corresponding to heparin levels of 0.3 to 0.6 U/mL prompts a multifactorial approach to ECMO management because no single laboratory test can be used to determine appropriate anticoagulation management.

Thromboelastography (TEG) aids in monitoring a patient's global hemostatic system by measuring the rate of clot formation, clot strength, and stability. The usefulness of TEG in pediatric settings, especially with neonates, is limited owing to a lack of neonatal reference values. In this study, neonatal TEG reference intervals were developed and results correlated with other coagulation test parameters. Samples were from women who delivered a neonate after at least 34 weeks of gestation in normal pregnancies. From the recovered placenta, cord blood from the umbilical vein or artery was collected within 30 minutes after delivery and tested. Neonatal TEG reaction time (time clot formation begins), clot firmness (shear elastic modulus strength), and platelet function analysis closure times were significantly lower than those in adult ranges (P< .001). When compared with the values for children, TEG reaction time, angle, coagulation index, clot firmness value, and clot kinetics (time from clot formation to time amplitude reaches 20 mm) were significantly different (P< .001) among neonates. TEG can be used to interpret the data for newborns by using reference values obtained in the present study.

Cochrane Library Cochrane Database of Systematic Reviews Normal saline (0.9% sodium chloride) versus heparin intermittent flushing for the prevention of occlusion in long-term central venous catheters in infants and children (Review) Bradford NK, Edwards RM, Chan RJ Bradford NK, Edwards RM, Chan RJ. Normal saline (0.9% sodium chloride) versus heparin intermittent flushing for the prevention of occlusion in long-term central venous catheters in infants and children.

The aim of this study was to investigate the association between foot type and the morphometry of selected muscles and tendons of the lower limb. Sixty-one healthy participants (31 male, 30 female; aged 27.1 ± 8.8 years) underwent gray-scale musculoskeletal ultrasound examination to determine the anterior-posterior (AP) thickness of tibialis anterior, tibialis posterior, and peroneus longus muscles and tendons as well as the Achilles tendon. Foot type was classified based on arch height and footprint measurements. Potentially confounding variables (height, weight, hip and waist circumference, rearfoot and ankle joint range of motion, and levels of physical activity) were also measured. Multiple linear regression models were used to determine the association between foot type with muscle and tendon morphometry accounting for potentially confounding variables. Foot type was significantly and independently associated with AP thickness of the tibialis anterior tendon, peroneus longus muscle, and Achilles tendon, accounting for approximately 7% to 16% of the variation. Flat-arched feet were associated with a thicker tibialis anterior tendon, a thicker peroneus longus muscle, and a thinner Achilles tendon. Foot type is associated with morphometry of tendons that control sagittal plane motion of the rearfoot; and the peroneus longus muscle that controls frontal plane motion of the rearfoot. These findings may be related to differences in tendon loading during gait.

PurposeChallenges experienced by staff in the Oncology Services Group at Queensland Children’s Hospital led to issues with staff retention, well-being, and stress on team culture. Therefore, a customized program was developed through a needs analysis to improve the well-being and resilience of oncology staff, enabling them to cope with stressors and critical incidents inherent in their everyday work and to flourish. The program included education, on-site counselors, mindfulness sessions, debriefing, well-being resources, and improved engagement, support, and communication.MethodsEvaluation of the program in the first year examined program participation, staff feedback following education workshops and mindfulness sessions, staff retention rates, and the results of an annual organizational staff survey and a program outcome survey.ResultsApproximately 76% of staff attended the Introduction to Well-being workshop, and 98% of responses to survey questions were positive. Staff also provided positive feedback on the other well-being workshops and sessions embedded within existing education programs. Employee Assistance Program counseling sessions had an 81% uptake, with a wide variety of presenting issues, 62% related to work. All participants in mindfulness sessions agreed that it was a valuable tool to improve clinical practice, 94% said it had an immediate positive impact on their well-being, and 70% agreed that they were applying mindfulness principles outside the sessions. Staff retention and turnover improved. Staff reported a positive effect on awareness of self-care, addressing risks to resilience, seeking support from trusted colleagues, coping with critical incidents, and the ability to interact positively with patients and families.ConclusionThe evaluation showed a positive impact on staff well-being. Although there was a wide variety of successful interventions reported in the literature, sustainability needs to be considered. Feedback on this program found that staff appreciated being listened to, valued, and supported through the strategies, and the ongoing program will continue to monitor staff needs and be responsive in building their resilience and well-being.