RESUMO
Complex interactions of the branching ureteric bud (UB) and surrounding mesenchymal cells during metanephric kidney development determine the final number of nephrons. Impaired nephron endowment predisposes to arterial hypertension and chronic kidney disease. In the kidney, extracellular matrix (ECM) proteins are usually regarded as acellular scaffolds or as the common histological end-point of chronic kidney diseases. Since only little is known about their physiological role in kidney development, we aimed for analyzing the expression and role of fibronectin. In mouse, fibronectin was expressed during all stages of kidney development with significant changes over time. At embryonic day (E) 12.5 and E13.5, fibronectin lined the UB epithelium, which became less pronounced at E16.5 and then switched to a glomerular expression in the postnatal and adult kidneys. Similar results were obtained in human kidneys. Deletion of fibronectin at E13.5 in cultured metanephric mouse kidneys resulted in reduced kidney sizes and impaired glomerulogenesis following reduced cell proliferation and branching of the UB epithelium. Fibronectin colocalized with alpha 8 integrin and fibronectin loss caused a reduction in alpha 8 integrin expression, release of glial-derived neurotrophic factor and expression of Wnt11, both of which are promoters of UB branching. In conclusion, the ECM protein fibronectin acts as a regulator of kidney development and is a determinant of the final nephron number.
Assuntos
Fibronectinas , Rim , Animais , Fibronectinas/metabolismo , Fibronectinas/genética , Camundongos , Humanos , Rim/metabolismo , Rim/embriologia , Proteínas Wnt/metabolismo , Proteínas Wnt/genética , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Proliferação de Células , Integrinas/metabolismo , Integrinas/genética , Camundongos Endogâmicos C57BL , Matriz Extracelular/metabolismo , Cadeias alfa de IntegrinasRESUMO
Chronic pain conditions are associated with abnormalities in brain structure and function. Moreover, some studies indicate that brain activity related to the subjective perception of chronic pain may be distinct from activity for acute pain. However, the latter are based on observations from cross-sectional studies. How brain activity reorganizes with transition from acute to chronic pain has remained unexplored. Here we study this transition by examining brain activity for rating fluctuations of back pain magnitude. First we compared back pain-related brain activity between subjects who have had the condition for â¼2 months with no prior history of back pain for 1 year (early, acute/subacute back pain group, n = 94), to subjects who have lived with back pain for >10 years (chronic back pain group, n = 59). In a subset of subacute back pain patients, we followed brain activity for back pain longitudinally over a 1-year period, and compared brain activity between those who recover (recovered acute/sub-acute back pain group, n = 19) and those in which the back pain persists (persistent acute/sub-acute back pain group, n = 20; based on a 20% decrease in intensity of back pain in 1 year). We report results in relation to meta-analytic probabilistic maps related to the terms pain, emotion, and reward (each map is based on >200 brain imaging studies, derived from neurosynth.org). We observed that brain activity for back pain in the early, acute/subacute back pain group is limited to regions involved in acute pain, whereas in the chronic back pain group, activity is confined to emotion-related circuitry. Reward circuitry was equally represented in both groups. In the recovered acute/subacute back pain group, brain activity diminished in time, whereas in the persistent acute/subacute back pain group, activity diminished in acute pain regions, increased in emotion-related circuitry, and remained unchanged in reward circuitry. The results demonstrate that brain representation for a constant percept, back pain, can undergo large-scale shifts in brain activity with the transition to chronic pain. These observations challenge long-standing theoretical concepts regarding brain and mind relationships, as well as provide important novel insights regarding definitions and mechanisms of chronic pain.
Assuntos
Encéfalo/patologia , Dor Crônica/patologia , Dor Crônica/psicologia , Emoções/fisiologia , Adulto , Análise de Variância , Dor nas Costas/patologia , Encéfalo/irrigação sanguínea , Mapeamento Encefálico , Estudos Transversais , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Modelos Lineares , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Metanálise como Assunto , Pessoa de Meia-Idade , Vias Neurais/irrigação sanguínea , Vias Neurais/patologia , Observação , Oxigênio/sangue , Medição da Dor , Escalas de Graduação Psiquiátrica , RecompensaRESUMO
Access to social services is important for the safety of children and ultimately for reunification of families involved in the child welfare system. The process of linking families to services however, varies by caseworker and can be cumbersome and time-consuming. The DCFS Needs Portal is an internet-based intervention to improve the timing and quality of social service referrals in Los Angeles County We used a case study approach including in-depth interviews, direct observations and user feedback obtained from the Needs Portal to 1) determine perceived benefits and barriers to adopting the Needs Portal and 2) report how the flow of information between users and developers was used to adapt to user needs. Our analyses revealed four major barriers: 1) caseworker apprehension regarding new technology, 2) variation in communication styles by user type, 3) lack of technological infrastructure and 4) competing workplace demands. Information sharing between developers and users has the potential to better meet the needs of users and ultimately maximize utilization of new technology. Although internet-based interventions are designed to inexpensively and effectively coordinate services, emerging interventions may require in-person assistance and modifications in order to succeed.
RESUMO
BACKGROUND: Video-laryngoscopes are marketed for intubation in difficult airway management. They provide a better view of the larynx and may facilitate tracheal intubation, but there is no adequately powered study comparing different types of video-laryngoscopes in a difficult airway scenario or in a simulated difficult airway situation. METHODS/DESIGN: The objective of this trial is to evaluate and to compare the clinical performance of three video-laryngoscopes with a guiding channel for intubation (Airtraq™, A. P. Advance™, King Vision™) and three video-laryngoscopes without an integrated tracheal tube guidance (C-MAC™, GlideScope™, McGrath™) in a simulated difficult airway situation in surgical patients. The working hypothesis is that each video-laryngoscope provides at least a 90% first intubation success rate (lower limit of the 95% confidence interval >0.9). It is a prospective, patient-blinded, multicenter, randomized controlled trial in 720 patients who are scheduled for elective surgery under general anesthesia, requiring tracheal intubation at one of the three participating hospitals. A difficult airway will be created using an extrication collar and taping the patients' head on the operating table to substantially reduce mouth opening and to minimize neck movement. Tracheal intubation will be performed with the help of one of the six devices according to randomization. Insertion success, time necessary for intubation, Cormack-Lehane grade and percentage of glottic opening (POGO) score at laryngoscopy, optimization maneuvers required to aid tracheal intubation, adverse events and technical problems will be recorded. Primary outcome is intubation success at first attempt. DISCUSSION: We will simulate the difficult airway and evaluate different video-laryngoscopes in this highly realistic and clinically challenging scenario, independently from manufacturers of the devices. Because of the sufficiently powered multicenter design this study will deliver important and cutting-edge results that will help clinicians decide which device to use for intubation of the expected and unexpected difficult airway. TRIAL REGISTRATION: NCT01692535.