Wolves: Behavior, Ecology, and Conservation: Photo Section II

Adult wolves are very attentive to the pups. Both parents feed and care for them. Any older siblings similarly participate in pup care and feeding. Kin selection is probably the best explanation for the latter behavior. Top: Photograph by Isaac Babcock. Bottom: Photograph by L. David Mech

Cofilin-actin rods, a hippocampal pathology in mouse models of human dementias, form from different inducers through a common molecular pathway

2020 Summer.Includes bibliographical references.To view the abstract, please see the full text of the document

Wolves: Behavior, Ecology, and Conservation: Photo Section II

Adult wolves are very attentive to the pups. Both parents feed and care for them. Any older siblings similarly participate in pup care and feeding. Kin selection is probably the best explanation for the latter behavior. Top: Photograph by Isaac Babcock. Bottom: Photograph by L. David Mech

Direct interaction of HIV gp120 with neuronal CXCR4 and CCR5 receptors induces cofilin-actin rod pathology via a cellular prion protein- and NOX-dependent mechanism.

Nearly 50% of individuals with long-term HIV infection are affected by the onset of progressive HIV-associated neurocognitive disorders (HAND). HIV infiltrates the central nervous system (CNS) early during primary infection where it establishes persistent infection in microglia (resident macrophages) and astrocytes that in turn release inflammatory cytokines, small neurotoxic mediators, and viral proteins. While the molecular mechanisms underlying pathology in HAND remain poorly understood, synaptodendritic damage has emerged as a hallmark of HIV infection of the CNS. Here, we report that the HIV viral envelope glycoprotein gp120 induces the formation of aberrant, rod-shaped cofilin-actin inclusions (rods) in cultured mouse hippocampal neurons via a signaling pathway common to other neurodegenerative stimuli including oligomeric, soluble amyloid-β and proinflammatory cytokines. Previous studies showed that synaptic function is impaired preferentially in the distal proximity of rods within dendrites. Our studies demonstrate gp120 binding to either chemokine co-receptor CCR5 or CXCR4 is capable of inducing rod formation, and signaling through this pathway requires active NADPH oxidase presumably through the formation of superoxide (O2-) and the expression of cellular prion protein (PrPC). These findings link gp120-mediated oxidative stress to the generation of rods, which may underlie early synaptic dysfunction observed in HAND

Recommendations on the Use of Ecosystem Modeling for Informing Ecosystem-Based Fisheries Management and Restoration Outcomes in the Gulf of Mexico

Ecosystem-based fisheries management (EBFM) and ecosystem restoration are gaining momentum worldwide, including in U.S. waters of the Gulf of Mexico (GOM). Ecosystem models are valuable tools for informing EBFM and restoration activities. In this paper, we provide guidance and a roadmap for ecosystem modeling in the GOM region, with an emphasis on model development and use of model products to inform EBFM and the increasing investments in restoration. We propose eight “best practices” for ecosystem modeling efforts, including (1) identification of priority management questions, (2) scenarios as simulation experiments, (3) calibration and validation needs, (4) sensitivity and uncertainty analyses, (5) ensuring transparency, (6) improving communication between ecosystem modelers and the various stakeholders, (7) documentation of modeling efforts, and (8) maintaining the ecosystem models and codes. Fisheries management in the USA adheres to a prescriptive set of calculations. Therefore, the use of ecosystem modeling in EBFM for the GOM will likely be incremental, starting with the incorporation of environmental variables into single-species assessments, the provision of background (stage-setting) information on environmental and food web effects (e.g., the impacts of lionfish Pterois spp. invasion), and strategic advice through management strategy evaluation. Management questions related to restoration in the GOM (e.g., the impacts of freshwater and sediment diversions as part of coastal restoration, habitat preservation, and rehabilitation; and measures to mitigate nutrient loading and hypoxia) have more flexibility in how they are addressed and thus are primed for immediate use of ecosystem modeling. The questions related to restoration are appropriate for ecosystem modeling, and data collection at the restoration project level can provide critical information for modeling to then scale up to regional responses. Ecosystem modeling efforts need to be initiated and advanced now in order for the tools to be ready in the near future. Addressing resource management issues and questions will benefit greatly from the proper use of ecosystem modeling

Recommendations on the Use of Ecosystem Modeling for Informing Ecosystem-Based Fisheries Management and Restoration Outcomes in the Gulf of Mexico

Ecosystem-based fisheries management (EBFM) and ecosystem restoration are gaining momentum worldwide, including in U.S. waters of the Gulf of Mexico (GOM). Ecosystem models are valuable tools for informing EBFM and restoration activities. In this paper, we provide guidance and a roadmap for ecosystem modeling in the GOM region, with an emphasis on model development and use of model products to inform EBFM and the increasing investments in restoration. We propose eight “best practices” for ecosystem modeling efforts, including (1) identification of priority management questions, (2) scenarios as simulation experiments, (3) calibration and validation needs, (4) sensitivity and uncertainty analyses, (5) ensuring transparency, (6) improving communication between ecosystem modelers and the various stakeholders, (7) documentation of modeling efforts, and (8) maintaining the ecosystem models and codes. Fisheries management in the USA adheres to a prescriptive set of calculations. Therefore, the use of ecosystem modeling in EBFM for the GOM will likely be incremental, starting with the incorporation of environmental variables into single-species assessments, the provision of background (stage-setting) information on environmental and food web effects (e.g., the impacts of lionfish Pterois spp. invasion), and strategic advice through management strategy evaluation. Management questions related to restoration in the GOM (e.g., the impacts of freshwater and sediment diversions as part of coastal restoration, habitat preservation, and rehabilitation; and measures to mitigate nutrient loading and hypoxia) have more flexibility in how they are addressed and thus are primed for immediate use of ecosystem modeling. The questions related to restoration are appropriate for ecosystem modeling, and data collection at the restoration project level can provide critical information for modeling to then scale up to regional responses. Ecosystem modeling efforts need to be initiated and advanced now in order for the tools to be ready in the near future. Addressing resource management issues and questions will benefit greatly from the proper use of ecosystem modeling