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Bank Korsgaard posted an update 3 days, 13 hours ago
Traumatic brain injury (TBI) is distinct from other neurological disorders because it is induced by a discrete event that applies extreme mechanical forces to the brain. This review describes how the brain senses, integrates, and responds to forces under both normal conditions and during injury. The response to forces is influenced by the unique mechanical properties of brain tissue, which differ by region, cell type, and sub-cellular structure. Elements such as the extracellular matrix, plasma membrane, transmembrane receptors, and cytoskeleton influence its properties. These same components also act as force-sensors, allowing neurons and glia to respond to their physical environment and maintain homeostasis. However, when applied forces become too large, as in TBI, these components may respond in an aberrant manner or structurally fail, resulting in unique pathological sequelae. This so-called “pathological mechanosensation” represents a spectrum of cellular responses, which vary depending on the overall biomechanical parameters of the injury and may be compounded by repetitive injuries. Voruciclib Such aberrant physical responses and/or damage to cells along with the resulting secondary injury cascades can ultimately lead to long-term cellular dysfunction and degeneration, often resulting in persistent deficits. Indeed, pathological mechanosensation not only directly initiates secondary injury cascades, but this post-physical damage environment provides the context in which these cascades unfold. Collectively, these points underscore the need to use experimental models that accurately replicate the biomechanics of TBI in humans. Understanding cellular responses in context with injury biomechanics may uncover therapeutic targets addressing various facets of trauma-specific sequelae.
The early and short-term efficacy of the snorkel/chimney technique for endovascular aortic aneurysm repair (ch-EVAR) have been previously reported. However, long-term ch-EVAR performance, vessel patency, and patient survival remain unknown. Our study evaluated the late outcomes to identify possible predictors of failure within the PERICLES (performance of the chimney technique for the treatment of complex aortic pathologies) registry.
Clinical and radiographic data from patients who had undergone ch-EVAR from 2008 to 2014 in the PERICLES registry were updated with an extension of the follow-up. Regression models were used to evaluate the relevant anatomic and operative characteristics as factors influencing the late results. We focused on patients with ≥30months of follow-up (mean, 46.6months; range, 30-120months).
A total of 517 patients from the initial PERICLES registry were included in the present analysis, from which the mean follow-up was updated from 17.1months to 28.2months (range, 1-120months).s significantly associated with persistent or late type Ia endoleak (odds ratio, 4.86; 95% confidence interval, 1.42-16.59; P= .012).
The present analysis of the PERICLES registry has provided the missing long-term experience for the ch-EVAR technique, showing favorable results with more than one half of the patients surviving for >5years and a chimney graft branch vessel patency of 92%. The absence of an infrarenal neck and treatment with a sealing zone diameter >30mm were the main anatomic long-term limits of the technique, requiring adequate preoperative planning and determination of the appropriate indication.
30 mm were the main anatomic long-term limits of the technique, requiring adequate preoperative planning and determination of the appropriate indication.Human epidermal growth factor receptor 2 positive (HER2+) advanced breast cancer (ABC) accounts for about 15-20% of all ABC cases. Large randomized trials have determined the standard first- and second-line treatments for this subgroup of patients, namely dual blockade plus chemotherapy and TDM1. However, no standard treatment is specifically recommended after TDM1, and most of the subsequent therapeutic choices commonly rely on old trials not optimally reflecting the current patient population. The recent FDA-approval of three novel anti-HER2 compounds is revolutionizing the field. In particular, trastuzumab deruxtecan was approved after showing unprecedented activity in a phase 2 trial for highly pretreated HER2+ ABC patients; tucatinib and neratinib were approved based on the results of the randomized HER2CLIMB and NALA trial, respectively. With an increasing arsenal of treatment options, clinical decision-making will need to take into account a variety of aspects, including differences in clinical trial designs, outcomes and toxicity profile of each drug, patient’s characteristics and preferences.In the early 20th century, August and Marie Krogh settled one of the most controversial questions in physiology, showing through elegant experiments that oxygen (O2) uptake at the lung is driven by passive diffusion alone. Krogh’s later work, on the regulation of local blood flow and capillary recruitment at the tissues, was awarded with the Nobel Prize in 1920. A century later it is still undisputed that O2 moves across tissues by diffusion, however, animals use active mechanisms to regulate and facilitate the passive process. Teleost fishes have evolved a mechanism by which adrenergic sodium-proton-exchangers (β-NHEs) on the red blood cell (RBC) membrane actively create H+ gradients that are short-circuited in the presence of plasma-accessible carbonic anhydrase (CA) at the tissue capillaries. The rapid acidification of the RBC reduces the O2 affinity of pH-sensitive haemoglobin, which increases the O2 diffusion gradient to the tissues. When RBCs leave the site of plasma-accessible CA, β-NHE activity recovers RBC pH during venous transit, to promote renewed O2 loading at the gills. This mechanism allows teleosts to unload more O2 at their tissues without compromising O2 diffusion gradients and therefore, to use the available O2 carrying capacity of the blood to a greater degree. In Atlantic salmon, β-NHE short-circuiting reduces the requirements on the heart by up to 30% during moderate exercise and even at rest, with important ecological implications. Thus, in some teleosts, the RBCs participate in regulating the systemic O2 flux by actively altering the passive diffusion of O2 that Krogh discovered.