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Notwithstanding the high safety level of the currently available blood for transfusion and the decreasing frequency of transfusion-related complications, administration of labile blood products to paediatric patients still poses unique challenges and considerations. The incidence of thalassaemia and sickle cell disease in the paediatric population may be high enough under specific racial and geographical contexts. Red cell transfusion is the cornerstone of β-thalassaemia treatment and one of the most effective ways to prevent or correct specific acute and chronic complications of sickle cell disease. However, this life-saving strategy comes with its own complications, such as additional iron overload, alloimmunization and haemolytic reactions, among others. In paediatrics, the dependency of the transfusion outcome upon disease and other recipient characteristics is more prominent compared with the adults, owing to differences in developmental maturity and physiology that render them more susceptible to common risks, exacerbate the host response to transfused cells, and modify the type or the clinical severity of the transfusion-related morbidity. The adverse branch of red cell transfusion is likely the overall effect of several factors acting synergistically to shape the clinical phenotype of this therapy, including inherent donor/blood unit variables, like antigenicity, red cell deformability and extracellular vesicles, as well as recipient variables, such as history of alloimmunization and inflammation level at time of transfusion. This review focuses on paediatric patients with β-thalassaemia and sickle cell disease as a recipient group with distinct transfusion-related characteristics, and introduces new concepts for consideration, not adequately studied and elucidated so far.  相似文献   
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Purpose of Review

Nutraceuticals are a form of complementary and alternative medicine that is commonly used by children and adolescents with migraine. In this review, observational studies, randomized controlled trials, systematic reviews, and meta-analyses on the efficacy and safety of single compound nutraceuticals for the management of migraine in children and adolescents were identified through a literature search of MEDLINE, Embase, and EBM Reviews—Cochrane Central Register of Controlled Trials.

Recent Findings

Twenty-one studies were reviewed, of which 11 were observational studies, 7 were randomized controlled trials, and 3 were systematic reviews. Six different nutraceuticals were included in the review: vitamin D, riboflavin, coenzyme Q10, magnesium, butterbur, and polyunsaturated fatty acids. All but three of the studies assessed the role of nutraceuticals in migraine prevention, while three studies evaluated the role of intravenous magnesium for acute migraine management. Overall, the quality and size of the studies were limited.

Summary

Due to low quality evidence and limited studies, no definite conclusions can be drawn on the efficacy of nutraceuticals for the treatment of pediatric migraine. Future studies are warranted in order to establish evidence upon which to define the role of nutraceuticals in this patient population.
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A critical component of nervous system development is synapse elimination during early postnatal life, a process known to depend on neuronal activity. Changes in synaptic strength in the form of long-term potentiation (LTP) and long-term depression (LTD) correlate with dendritic spine enlargement or shrinkage, respectively, but whether LTD can lead to an actual separation of the synaptic structures when the spine shrinks or is lost remains unknown. Here, we addressed this issue by using concurrent imaging and electrophysiological recording of live synapses. Slices of rat hippocampus were cultured on multielectrode arrays, and the neurons were labeled with genes encoding red or green fluorescent proteins to visualize presynaptic and postsynaptic neuronal processes, respectively. LTD-inducing stimulation led to a reduction in the synaptic green and red colocalization, and, in many cases, it induced a complete separation of the presynaptic bouton from the dendritic spine. This type of synapse loss was associated with smaller initial spine size and greater synaptic depression but not spine shrinkage during LTD. All cases of synapse separation were observed without an accompanying loss of the spine during this period. We suggest that repeated low-frequency stimulation simultaneous with LTD induction is capable of restructuring synaptic contacts. Future work with this model will be able to provide critical insight into the molecular mechanisms of activity- and experience-dependent refinement of brain circuitry during development.  相似文献   
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