In tissue engineering and regenerative medicine, a biomaterial provides mechanical support and biochemical signals to encourage cell attachment and modulate cell behaviour. Nature’s template for a ...biomaterial is the extracellular matrix (ECM). The ECM contains intrinsic biochemical and mechanical cues that regulate cell phenotype and function in development, in homeostasis and in response to injury. The use of ECM-based materials in biomedical research has advanced from coating cell culture plates with purified ECM components to the design of ECM-mimicking biomaterials and the engineering of decellularized tissues aimed at recapitulating the dynamics, composition and structure of the ECM. In this Review, we highlight important matrix properties and functions in the context of tissue engineering and regenerative medicine, consider techniques such as proteomics for the investigation of matrix structure and composition and discuss different engineering strategies for the design of matrix-mimicking biomaterials. Tissue, whole organ and cell culture decellularization approaches are examined for their potential to preserve the tissue-specific biochemical composition and ultrastructure of the ECM and for the development of biomaterials that promote the formation of functional tissues in clinical applications. Finally, we investigate challenges and opportunities of ECM biomaterials for the design of organotypic models to study disease progression, for the ex vivo creation of engineered tissue and for the clinical translation of functional tissue reconstruction strategies in vivo.
The network theory conceptualizes mental disorders as complex networks of symptoms influencing each other by creating feedback loops, leading to a self-sustained syndromic constellation. Symptoms ...central to the network have the greatest impact in sustaining the rest of symptoms. This analysis focused on the network structure of depressive symptoms in late-life because of their distinct etiologic factors, clinical presentation, and outcomes. We analyzed cross-sectional data from wave 2 of the 19 country Survey of Health, Ageing, and Retirement in Europe (SHARE) and included non-institutionalized adults aged 65 years or older (mean age 74 years, 59% females) endorsing at least one depressive symptom on the EURO-D scale for depression (N =8,557). We characterized the network structure of depressive symptoms in late-life and used indices of "strength", "betweenness", and "closeness" to identify symptoms central to the network. We used a case-dropping bootstrap procedure to assess network stability. Death wishes, depressed mood, loss of interest, and pessimism had the highest values of centrality. Insomnia, fatigue and appetite changes had lower centrality values. The identified network remained stable after dropping 74.5% of the sample. Sex or age did not significantly influence the network structure. In conclusion, death wishes, depressed mood, loss of interest, and pessimism constitute the "backbone" that sustains depressive symptoms in late-life. Symptoms central to the network of depressive symptoms may be used as targets for novel, focused interventions and in studies investigating neurobiological processes central to late-life depression.
Biomarkers have transformed modern medicine but remain largely elusive in psychiatry, partly because there is a weak correspondence between diagnostic labels and their neurobiological substrates. ...Like other neuropsychiatric disorders, depression is not a unitary disease, but rather a heterogeneous syndrome that encompasses varied, co-occurring symptoms and divergent responses to treatment. By using functional magnetic resonance imaging (fMRI) in a large multisite sample (n = 1,188), we show here that patients with depression can be subdivided into four neurophysiological subtypes ('biotypes') defined by distinct patterns of dysfunctional connectivity in limbic and frontostriatal networks. Clustering patients on this basis enabled the development of diagnostic classifiers (biomarkers) with high (82-93%) sensitivity and specificity for depression subtypes in multisite validation (n = 711) and out-of-sample replication (n = 477) data sets. These biotypes cannot be differentiated solely on the basis of clinical features, but they are associated with differing clinical-symptom profiles. They also predict responsiveness to transcranial magnetic stimulation therapy (n = 154). Our results define novel subtypes of depression that transcend current diagnostic boundaries and may be useful for identifying the individuals who are most likely to benefit from targeted neurostimulation therapies.
Although the preceding chapters discuss much of the new knowledge of neurocircuitry of neuropsychiatric diseases, and an invasive approach to treatment, this chapter describes and reviews the ...noninvasive methods of testing circuit-based theories and treating neuropsychiatric diseases that do not involve implanting electrodes into the brain or on its surface. These techniques are transcranial magnetic stimulation, vagus nerve stimulation, and transcranial direct current stimulation. Two of these approaches have FDA approval as therapies.
Innate cells are responsible for the rapid recognition of infection and mediate essential mechanisms of pathogen elimination, and also facilitate adaptive immune responses. We review here the ...numerous intricate interactions among innate cells that initiate protective immunity. The efficient eradication of pathogens depends on the coordinated actions of multiple cells, including innate cells and epithelial cells. Rather than acting as isolated effector cells, innate cells are in constant communication with other responding cells of the immune system, locally and distally. These interactions are critically important for the efficient control of primary infections as well for the development of 'trained' innate cells that facilitate the rapid elimination of homologous or heterologous infections.
Polymeric guanylate-binding proteins (GBPs) physically dismember the vacuole membrane formed by Toxoplasma gondii while nitric oxide (NO) poisons and inhibits parasite replication within interferon ...(IFN)-γ activated macrophages. Zhao et al. report a novel mechanism for synergy between these classical microbicidal and microbistatic effectors in cell-autonomous immunity to the intracellular parasites.
Polymeric guanylate-binding proteins (GBPs) physically dismember the vacuole membrane formed by Toxoplasma gondii while nitric oxide (NO) poisons and inhibits parasite replication within interferon (IFN)-γ activated macrophages. Zhao et al. report a novel mechanism for synergy between these classical microbicidal and microbistatic effectors in cell-autonomous immunity to the intracellular parasites.
Cuffless Blood Pressure Measurement Mukkamala, Ramakrishna; Stergiou, George S; Avolio, Alberto P
Annual review of biomedical engineering,
2022-Jun-06, Letnik:
24, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Cuffless blood pressure (BP) measurement has become a popular field due to clinical need and technological opportunity. However, no method has been broadly accepted hitherto. The objective of this ...review is to accelerate progress in the development and application of cuffless BP measurement methods. We begin by describing the principles of conventional BP measurement, outstanding hypertension hypotension problems that could be addressed with cuffless methods, and recent technological advances, including smartphone proliferation and wearable sensing, that are driving the field. We then present all major cuffless methods under investigation, including their current evidence. Our presentation includes calibrated methods (i.e., pulse transit time, pulse wave analysis, and facial video processing) and uncalibrated methods (i.e., cuffless oscillometry, ultrasound, and volume control). The calibrated methods can offer convenience advantages, whereas the uncalibrated methods do not require periodic cuff device usage or demographic inputs. We conclude by summarizing the field and highlighting potentially useful future research directions.
Pioneering anesthesiologists Paul Wood, M.D., and Arthur Guedel, M.D., were Hoosiers who migrated from America's Heartland to opposite coasts. Dr. Wood moved east to New York in 1913; Dr. Guedel, ...west to California in 1928. By 1962, each pioneer had been honored with a namesake anesthesia museum. Fast-forwarding 55 yr, two young anesthesia historians, California's Jane Moon, M.D., and Pennsylvania's Melissa Coleman, M.D., met at the 2017 International Symposium of the History of Anesthesia in Boston. Today, these women are chairs of the Wood Library-Museum's Archives and Museum Committees, respectively. As the newest authors of "Anesthesiology Reflections," Drs. Coleman and Moon leave their coastal states semiannually for board meetings at the Wood Library-Museum of Anesthesiology, returning as legacies of Drs. Wood and Guedel…back to the American Heartland.
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