A simple in vitro model for investigating epithelial/mesenchymal interactions: keratinocyte inhibition of fibroblast proliferation and fibronectin synthesis

Hypertrophic scarring and graft contracture are major causes of morbidity after burn injuries. It is well established that application of a split-thickness skin graft reduces scarring and contraction, and cultured epithelial autografts have a similar effect. To investigate the influence of keratinocytes on fibroblast proliferation and fibronectin synthesis, we used an in vitro separated co-culture model in which epithelial sheets were cultured above fibroblast monolayers without physical contact. We also investigated the response of fibroblasts to keratinocyte-conditioned medium (KCM) obtained from confluent and subconfluent keratinocyte monolayers. Both cultured epithelial sheets, composed of adherent fully confluent keratinocytes, and their conditioned medium, reduced fibroblast proliferation. However, KCM from subconfluent keratinocytes stimulated fibroblast proliferation at low concentrations while inhibiting it at higher concentrations, indicating that keratinocytes can produce both mitogenic and growth-inhibiting factors for fibroblasts. KCM, but not epithelial sheet co-culture, also inhibited fibroblast fibronectin synthesis. This indicates regulation of fibroblast phenotype by soluble factors released by the keratinocyte and also suggests that there is a dialogue between keratinocytes and fibroblasts with respect to fibronectin production. We conclude that this separated co-culture model is a simple way to study epithelial/mesenchymal communication particularly with respect to the role of the fibroblast in wound healing.     

LESIONS OF THE MID-SHAFT OF THE HUMERUS PRESENTING AS SHOULDER CAPSULITIS

We describe three patients who presented with pain and restrictionof movement at the shoulder suggestive of capsulitis, but provedto have lesions of the mid-shaft of the humerus. It is importantto be aware of the possibility of this cause of a ‘frozenshoulder’, since radiographs of the shoulder are usuallycropped at the mid-humerus and lesions at this level may easilybe missed. A radiograph of the entire humerus, or an isotopebone scan, may be more useful than repeated shoulder radiographsin patients whose shoulder symptoms do not respond to standardtreatment KEY WORDS: Shoulder joint, Humerus, Radiographs, Pain Department of Rheumatology, The Whittington Hospita HighgateHill, London N19 5NF     

Left Septal Atrial Tachycardias: Electrocardiographic and Electrophysiologic Characterization of a Paraseptal Focus

Left Septal Atrial Tachycardias. Objective: The objective was to characterize the electrocardiographic and electrophysiological features of focal atrial tachycardia (FAT) originating from the left septum (LS). Background: FAT is recognized to occur at predefined anatomic locations rather than randomly throughout the atria. We describe the ECG and EP features of ATs originating from the LS as an important site for apparent perinodal tachycardias. Methods: Nine patients presenting with LS FAT from a consecutive series of 384 underwent EP/RFA for symptomatic FAT. Results: The mean age was 56 ± 12 years; 7 female with symptoms for 36 ± 28 months. P wave morphology (PWM) was negative/positive in lead V1 and across the precordial leads and negative or negative/positive in inferior leads in all patients. Tachycardia was incessant in 6 out of 9 patients with a mean tachycardia cycle length 421 ± 56 milliseconds. His A was ahead of P wave in all patients (mean ?15 ± 5 milliseconds) and earlier than CS proximal (mean 4 ± 9 milliseconds). Successful acute focal ablation achieved at a mean of 31 ± 12 milliseconds ahead of P wave with no recurrences at a mean follow‐up of 30 ± 28 months. Conclusion: Although the left septum is an uncommon site for focal AT an awareness of this location for harboring foci is particularly important when mapping apparently right‐sided septal tachycardias. (J Cardiovasc Electrophysiol, Vol. 24, pp. 413‐418, April 2013)     

Understanding the essential elements of work-based learning and its relevance to everyday clinical practice

williams c. (2010) Journal of Nursing Management  18, 624–632
Understanding the essential elements of work-based learning and its relevance to everyday clinical practice Aim To critically review the work-based learning literature and explore the implications of the findings for the development of work-based learning programmes. Background With NHS budgets under increasing pressure, and challenges to the impact of classroom-based learning on patient outcomes, work-based learning is likely to come under increased scrutiny as a potential solution. Evidence from higher education institutions suggests that work-based learning can improve practice, but in many cases it is perceived as little more than on-the-job training to perform tasks. Evaluation The CINAHL database was searched using the keywords work-based learning, work-place learning and practice-based learning. Those articles that had a focus on post-registration nursing were selected and critically reviewed. Key issues Using the review of the literature, three key issues were explored. Work-based learning has the potential to change practice. Learning how to learn and critical reflection are key features. For effective work-based learning nurses need to take control of their own learning, receive support to critically reflect on their practice and be empowered to make changes to that practice. Conclusions A critical review of the literature has identified essential considerations for the implementation of work-based learning. A change in culture from classroom to work-based learning requires careful planning and consideration of learning cultures. Implications for nursing management To enable effective work-based learning, nurse managers need to develop a learning culture in their workplace. They should ensure that skilled facilitation is provided to support staff with critical reflection and effecting changes in practice. Contribution to New Knowledge This paper has identified three key issues that need to be considered in the development of work-based learning programmes.     

Neuroimaging in childhood arterial ischaemic stroke: evaluation of imaging modalities and aetiologies

Aim The aim of this study was to describe neuroimaging patterns associated with arterial ischaemic stroke (AIS) in childhood and to differentiate them according to stroke aetiology. Method Clinical and neuroimaging (acute and follow‐up) findings were analysed prospectively in 79 children (48 males, 31 females) aged 2 months to 15 years 8 months (median 5y 3mo) at the time of stroke by the Swiss Neuropaediatric Stroke Registry from 2000 to 2006. Results Stroke was confirmed in the acute period in 36 out of 41 children who underwent computed tomography, in 53 of 57 who underwent T2‐weighted magnetic resonance imaging (MRI) and in all 48 children who underwent diffusion‐weighted MRI. AIS occurred in the anterior cerebral artery (ACA) in 63 participants and in all cases was associated with lesions of the middle cerebral artery (MCA). The lesion was cortical–subcortical in 30 out of 63 children, cortical in 25 out of 63, and subcortical in 8 of 63 children. Among participants with AIS in the posterior circulation territory, the stroke was cortical–subcortical in 8 out of 16, cortical in 5 of 16, and thalamic in 3 out of 16 children. Interpretation AIS mainly involves the anterior circulation territory, with both the ACA and the MCA being affected. The classification of Ganesan is an appropriate population‐based classification for our Swiss cohort, but the neuroimaging pattern alone is insufficient to determine the aetiology of stroke in a paediatric population. The results show a poor correlation between lesion pattern and aetiology.     

Nursing Care of the Neonate Receiving High-Frequency Jet Ventilation

Respiratory distress remains a major source of morbidity and mortality among infants, despite advances in conventional mechanical ventilation over the past 20 years. High-frequency jet ventilation provides an alternative treatment modality for neonates suffering from pulmonary air leak syndromes, such as pulmonary interstitial emphysema and pneumothorax. This new technology presents special challenges to the nurse caring for these critically ill neonates and their families.     

Diagnosis of Ventricular Tachycardia Using a Pacemaker Holter Function

The diagnosis of ventricular tachycardia (VT) using the Holter function of an implanted pacemaker has not yet been reported. We present the case of a patient with episodes of slow VT. hemodynamically stable, but in whom long lasting attacks were not identified by the patient as VT recurrences, finally leading to progressive heart failure. Prospective analysis of the 24-hour ECG and comparison with the pacemaker Holter data allowed us to determine diagnostic criteria to recognize VT using the pacemaker Holter function. Using these criteria it was possible to retrospectively diagnose VT occurrence during the weeks when the patient was out-of-hospital.