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The immune-mediated necrotizing myopathies (IMNM) are autoimmune myositides clinically characterized by proximal predominant weakness and elevated creatine kinase (CK). They may be associated with autoantibodies (anti-HMGCR, anti-SRP), triggered by statin use (e.g., anti-HMGCR myopathy), associated with cancer, or may be idiopathic. Immunotherapy is required to improve strength and decrease the CK level, but no therapies are currently approved by the U.S. Food and Drug Administration for the treatment of IMNM. The optimal treatment strategy for IMNM is currently unknown and wide practice variation exists in the management of this condition. However, observational studies and expert opinion suggest that certain therapies may be more effective for the different serological subtypes of IMNM. HMGCR IMNM often responds favorably to intravenous immunoglobulin (IVIG) even as monotherapy. Signal recognition peptide and seronegative IMNM typically require combination immunotherapy, most often consisting of an oral immunosuppressant, corticosteroids, and IVIG or rituximab. Patients often remain on immunotherapy for years and relapse is common during tapering of immunotherapy. Further studies are needed to guide the optimal management of these patients.
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Miositis , Humanos , Miositis/inmunología , Miositis/terapia , Miositis/tratamiento farmacológico , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/terapia , Enfermedades Autoinmunes/tratamiento farmacológico , Inmunoterapia/métodos , Autoanticuerpos/inmunología , Inmunoglobulinas Intravenosas/uso terapéutico , Enfermedades Musculares/inmunología , Enfermedades Musculares/terapia , Enfermedades Musculares/tratamiento farmacológico , Hidroximetilglutaril-CoA Reductasas/inmunología , Necrosis , Manejo de la EnfermedadRESUMEN
Conservationists spend considerable resources to create and enhance wildlife habitat. Monitoring how species respond to these efforts helps managers allocate limited resources. However, monitoring efforts often encounter logistical challenges that are exacerbated as geographic extent increases. We used autonomous recording units (ARUs) and automated acoustic classification to mitigate the challenges of assessing Eastern Whip-poor-will (Antrostomus vociferus) response to forest management across the eastern USA. We deployed 1263 ARUs in forests with varying degrees of management intensity. Recordings were processed using an automated classifier and the resulting detection data were used to assess occupancy. Whip-poor-wills were detected at 401 survey locations. Across our study region, whip-poor-will occupancy decreased with latitude and elevation. At the landscape scale, occupancy decreased with the amount of impervious cover, increased with herbaceous cover and oak and evergreen forests, and exhibited a quadratic relationship with the amount of shrub-scrub cover. At the site-level, occupancy was negatively associated with basal area and brambles (Rubus spp.) and exhibited a quadratic relationship with woody stem density. Implementation of practices that create and sustain a mosaic of forest age classes and a diverse range of canopy closure within oak (Quercus spp.) dominated landscapes will have the highest probability of hosting whip-poor-wills. The use of ARUs and a machine learning classifier helped overcome challenges associated with monitoring a nocturnal species with a short survey window across a large spatial extent. Future monitoring efforts that combine ARU-based protocols and mappable fine-resolution structural vegetation data would likely further advance our understanding of whip-poor-will response to forest management.
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Conservación de los Recursos Naturales , Ecosistema , Bosques , Animales , Conservación de los Recursos Naturales/métodosRESUMEN
Objectives: Facial-onset sensory and motor neuronopathy (FOSMN) is a rare neuromuscular disorder characterized by progressive facial sensory impairment followed by motor dysfunction in a rostro-caudal distribution. FOSMN is clinically and pathologically associated with amyotrophic lateral sclerosis and frontotemporal dementia (ALS/FTD). In contrast to ALS/FTD, the genetic profile of patients with FOSMN and the role of genetic testing are poorly defined. Methods: A 66-year-old woman was evaluated in our neuromuscular clinic for progressive facial pain, dysphagia, and dysarthria. Her diagnostic evaluation included brain and cervical MRI, nerve conduction studies and EMG, and an ALS/FTD next-generation sequencing panel. Results: The patient was diagnosed with FOSMN, and we identified a N390D variant in transactive response DNA-binding protein (TDP-43/TARDBP). This variant has never been reported in FOSMN but was previously reported in 2 cases of ALS, and a N390S variant was also previously reported in FOSMN. A review of the literature revealed that TARDBP mutations are overrepresented in patients with FOSMN compared with patients with ALS/FTD. By contrast, other common familial forms of ALS, including C9ORF72 or SOD1, are respectively absent or rare in FOSMN. Discussion: FOSMN is pathologically and genetically associated with TDP-43. Therefore, ALS genetic testing that includes specifically TARDBP should be considered in patients with FOSMN.
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Tree regeneration shapes forest carbon dynamics by determining long-term forest composition and structure, which suggests that threats to natural regeneration may diminish the capacity of forests to replace live tree carbon transferred to the atmosphere or other pools through tree mortality. Yet, the potential implications of tree regeneration patterns for future carbon dynamics have been sparsely studied. We used forest inventory plots to investigate whether the composition of existing tree regeneration is consistent with aboveground carbon stock loss, replacement, or gain for forests across the northeastern and midwestern USA, leveraging a recently developed method to predict the likelihood of sapling recruitment from seedling abundance tallied within six seedling height classes. A comparison of carbon stock predictions from tree and seedling composition suggested that 29% of plots were poised to lose carbon based on seedling composition, 55% were poised for replacement of carbon stocks (<5 Mg ha-1 difference) and 16% were poised to gain carbon. Forests predicted to lose carbon tended to be on steeper slopes, at lower latitudes, and in rolling upland environments. Although plots predicted to gain and lose carbon had similar stand ages, carbon loss plots had greater current carbon stocks. Synthesis and applications. Our results demonstrate the utility of considering tree regeneration through the lens of carbon replacement to develop effective management strategies to secure long-term carbon storage and resilience in the context of global change. Forests poised to lose C due to climate change and other stressors could be prioritized for regeneration strategies that enhance long-term carbon resilience and stewardship.
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Objective. Macrophages and astrocytes play a crucial role in the aftermath of a traumatic spinal cord injury (SCI). Infiltrating macrophages adopt a pro-inflammatory phenotype while resident astrocytes adopt a neurotoxic phenotype at the injury site, both of which contribute to neuronal death and inhibit axonal regeneration. The cytokine interleukin-4 (IL-4) has shown significant promise in preclinical models of SCI by alleviating the macrophage-mediated inflammation and promoting functional recovery. However, its effect on neurotoxic reactive astrocytes remains to be elucidated, which we explored in this study. We also studied the beneficial effects of a sustained release of IL-4 from an injectable biomaterial compared to bolus administration of IL-4.Approach. We fabricated a heparin-based coacervate capable of anchoring and releasing bioactive IL-4 and tested its efficacyin vitroandin vivo. Main results. We show that IL-4 coacervate is biocompatible and drives a robust anti-inflammatory macrophage phenotype in culture. We also show that IL-4 and IL-4 coacervate can alleviate the reactive neurotoxic phenotype of astrocytes in culture. Finally, using a murine model of contusion SCI, we show that IL-4 and IL-4 coacervate, injected intraspinally 2 d post-injury, can reduce macrophage-mediated inflammation, and alleviate neurotoxic astrocyte phenotype, acutely and chronically, while also promoting neuroprotection with significant improvements in hindlimb locomotor recovery. We observed that IL-4 coacervate can promote a more robust regenerative macrophage phenotypein vitro, as well as match its efficacyin vivo,compared to bolus IL-4.Significance. Our work shows the promise of coacervate as a great choice for local and prolonged delivery of cytokines like IL-4. We support this by showing that the coacervate can release bioactive IL-4, which acts on macrophages and astrocytes to promote a pro-regenerative environment following a SCI leading to robust neuroprotective and functional outcomes.
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Astrocitos , Interleucina-4 , Recuperación de la Función , Traumatismos de la Médula Espinal , Animales , Femenino , Ratones , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Células Cultivadas , Preparaciones de Acción Retardada/administración & dosificación , Interleucina-4/administración & dosificación , Interleucina-4/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones Endogámicos C57BL , Fenotipo , Recuperación de la Función/efectos de los fármacos , Recuperación de la Función/fisiología , Traumatismos de la Médula Espinal/tratamiento farmacológico , Traumatismos de la Médula Espinal/fisiopatología , Traumatismos de la Médula Espinal/metabolismoRESUMEN
Cold-air pooling is an important topoclimatic process that creates temperature inversions with the coldest air at the lowest elevations. Incomplete understanding of sub-canopy spatiotemporal cold-air pooling dynamics and associated ecological impacts hinders predictions and conservation actions related to climate change and cold-dependent species and functions. To determine if and how cold-air pooling influences forest composition, we characterized the frequency, strength, and temporal dynamics of cold-air pooling in the sub-canopy at local to regional scales in New England, USA. We established a network of 48 plots along elevational transects and continuously measured sub-canopy air temperatures for 6-10 months (depending on site). We then estimated overstory and understory community temperature preferences by surveying tree composition in each plot and combining these data with known species temperature preferences. We found that cold-air pooling was frequent (19-43% seasonal occurrences) and that sites with the most frequent inversions displayed inverted forest composition patterns across slopes with more cold-adapted species, namely conifers, at low instead of high elevations. We also observed both local and regional variability in cold-air pooling dynamics, revealing that while cold-air pooling is common, it is also spatially complex. Our study, which uniquely focused on broad spatial and temporal scales, has revealed some rarely reported cold-air pooling dynamics. For instance, we discovered frequent and strong temperature inversions that occurred across seasons and in some locations were most frequent during the daytime, likely affecting forest composition. Together, our results show that cold-air pooling is a fundamental ecological process that requires integration into modeling efforts predicting future forest vegetation patterns under climate change, as well as greater consideration for conservation strategies identifying potential climate refugia for cold-adapted species.
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Current vascular grafts, primarily Gore-Tex® and Dacron®, don't integrate with the host and have low patency in small-diameter vessels (<6 mm). Biomaterials that possess appropriate viscoelasticity, compliance, and high biocompatibility are essential for their application in small blood vessels. We have developed metal ion crosslinked poly(propanediol-co-(hydroxyphenyl methylene)amino-propanediol sebacate) (M-PAS), a biodegradable elastomer with a wide range of mechanical properties. We call these materials metallo-elastomers. An initial test on Zn-, Fe-, and Cu-PAS grafts reveals that Cu-PAS is the most suitable because of its excellent elastic recoil and well-balanced polymer degradation/tissue regeneration rate. Here we report host remodeling of Cu-PAS vascular grafts in rats over one year. 76 % of the grafts remain patent and >90 % of the synthetic polymer is degraded by 12 months. Extensive cell infiltration leads to a positive host remodeling. The remodeled grafts feature a fully endothelialized lumen. Circumferentially organized smooth muscle cells, elastin fibers, and widespread mature collagen give the neoarteries mechanical properties similar to native arteries. Proteomic analysis further reveals the presence of important vascular proteins in the neoarteries. Evidence suggests that Cu-PAS is a promising material for engineering small blood vessels.