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  Malnutrition in Chronic Kidney Disease

  Iorember, Franca M.; Univ Arizona, Coll Med Phoenix, Dept Child Hlth (Frontiers, 2018-06-20)

  Patients with chronic kidney disease are at substantial risk for malnutrition, characterized by protein energy wasting and micronutrient deficiency. Studies show a high prevalence rate of malnutrition in both children and adults with chronic kidney disease. Apart from abnormalities in growth hormone-insulin like growth factor axis, malnutrition also plays a role in the development of stunted growth, commonly observed in children with chronic kidney disease. The pathogenic mechanisms of malnutrition in chronic kidney disease are complex and involve an interplay of multiple pathophysiologic alterations including decreased appetite and nutrient intake, hormonal derangements, metabolic imbalances, inflammation, increased catabolism, and dialysis related abnormalities. Malnutrition increases the risk of morbidity, mortality and overall disease burden in these patients. The simple provision of adequate calorie and protein intake does not effectively treat malnutrition in patients with chronic kidney disease owing to the intricate and multifaceted derangements affecting nutritional status in these patients. A clear understanding of the pathophysiologic mechanisms involved in the development of malnutrition in chronic kidney disease is necessary for developing strategies and interventions that are effective, and capable of restoring normal development and mitigating negative clinical outcomes. In this article, a review of the pathophysiologic mechanisms of malnutrition in chronic kidney disease is presented.
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  Modeling Fire Pathways in Montane Grassland-Forest Ecotones

  Conver, Joshua L.; Falk, Donald A.; Yool, Stephen R.; Parmenter, Robert R.; Univ Arizona, Sch Nat Resources & Environm; Univ Arizona, Sch Geog & Dev (Springer, 2018-02-01)

  Fire plays a key role in regulating the spatial interactions between adjacent vegetation types from the stand to the landscape scale. Fire behavior modeling can facilitate the understanding of these interactions and help managers restore or maintain fire’s natural role. The Valles Caldera National Preserve (VALL), in the Jemez Mountains of northern New Mexico, USA, contains one of the largest montane grasslands in North America and extensive areas of grassland-forest ecotone. We used the Minimum Travel Time (MTT) module in FlamMap to investigate the primary fire-growth vectors on the VALL landscape for the 50th, 90th, and 99th percentile of fire weather conditions. We evaluated whether modeled fire-growth vectors tended to follow the grassland-forest ecotone or if fire traveled directly across the grasslands and over the upland forest with a chi-square test. Our results indicated that the ecotone is a primary corridor for fire growth on the VALL landscape. Regular fire spread along the grassland-forest ecotone may help stabilize the boundary zone between these two dynamic communities by preventing forest encroachment into the grassland and maintaining an open stand structure. Identifying the dominant fire corridors will help land managers re-establish the spatial and process dynamics of the natural fire regime.
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  Ankle Fracture-Dislocations: A Review

  Morin, Matthew; Lawson, Keith; Univ Arizona, Coll Med (Sage, 2018-09-20)

  Ankle fractures are common musculoskeletal injuries that may result in tibiotalar joint dislocations. Ankle fracture-dislocations occur via similar mechanisms as ankle fractures, although the persistence or magnitude of the deforming force is sufficient to disrupt any remaining bony or soft-tissue stability. Ankle fracture-dislocations likely represent distinct clinical entities, as the pathology, management, and patient outcomes following these injuries differ from those seen in more common ankle fractures without dislocation. Ankle fracture-dislocations have higher rates of concomitant injury including open fractures, chondral lesions, and intra-articular loose bodies. Long-term outcomes in ankle fracture-dislocations are worse than ankle fractures without dislocation. Higher rates of posttraumatic osteoarthritis and chronic pain have also been reported. In this review, we discuss the current literature regarding the history, management, and outcomes of ankle-fracture dislocations and highlight the need for future study.
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  Maqlaqsyalank hemyeega: Goals and expectations of Klamath-Modoc revitalization

  Dupris, Joseph; Univ Arizona (UNIV HAWAII PRESS, 2019-03)

  This paper documents a collaboration between the Klamath Tribes and the American Indian Language Development Institute (AILDI) focused on intra-community capacity-building and early stages of language planning through immersion activities, survey responses, and discussion of intra-community involvement. In December 2016, I facilitated a three-day maqlaqsyals (Klamath-Modoc language) immersion workshop, "maqlaqsyalank henlyeega", on the Klamath reservation. Each day, immersion lessons focused on developing conversational use of maqlaqsyals between participants. During each lunch hour, participants shared personal goals and priorities regarding successful language revitalization. Ten tribal community members, including myself, made explicit their interest of sharing knowledge within the larger tribal community. Many of the workshop participants expressed the goal of using the language with their families while some participants expressed that the workshop had already helped them reach a personal goal in three days. Participants also discussed obtaining linguistic resources and establishing domains of language use. Understanding current interests of language in my tribal community provides early steps toward developing the framework of a "good linguist" in the maqlaqsyals revitalization movement.
• The lipidated connexin mimetic peptide SRPTEKT-Hdc is a potent inhibitor of Cx43 channels with specificity for the pS368 phospho-isoform

  Cotter, Maura L; Boitano, Scott; Lampe, Paul D; Solan, Joell L; Vagner, Josef; Ek-Vitorin, Jose F; Burt, Janis M; Univ Arizona, Dept Pharmacol; Univ Arizona, Bio5 Inst; Univ Arizona, Asthma & Airway Dis Res Ctr; et al. (AMER PHYSIOLOGICAL SOC, 2019-10-07)

  Connexin (Cx) mimetic peptides derived from extracellular loop II sequences (e.g., Gap27: SRPTEKTIFII; Peptide5: VDCFLSRPTEKT) have been used as reversible, Cx-specific blockers of hemichannel (HCh) and gap junction channel (GJCh) function. These blockers typically require high concentrations (~5 µM, <1 h for HCh; ~100 µM, >1 h for GJCh) to achieve inhibition. We have shown that addition of a hexadecyl (Hdc) lipid tail to the conserved SRPTEKT peptide sequence (SRPTEKT-Hdc) results in a novel, highly efficacious, and potent inhibitor of mechanically induced Ca2+-wave propagation (IC50 64.8 pM) and HCh-mediated dye uptake (IC50 45.0 pM) in Madin-Darby canine kidney cells expressing rat Cx43 (MDCK43). The lack of similar effect on dye coupling (NBD-MTMA) suggested channel conformation-specific inhibition. Here we report that SRPTEKT-Hdc inhibition of Ca2+-wave propagation, dye coupling, and dye uptake depended on the functional configuration of Cx43 as determined by phosphorylation at serine 368 (S368). Ca2+-wave propagation was enhanced in MDCK cells expressing single-site mutants of Cx43 that mimicked (MDCK43-S368D) or favored (MDCK43-S365A) phosphorylation at S368. Furthermore, SRPTEKT-Hdc potently inhibited GJCh-mediated Ca2+-wave propagation (IC50 230.4 pM), dye coupling, and HCh-mediated dye uptake in MDCK43-S368D and -S365A cells. In contrast, Ca2+-wave propagation, dye coupling, and dye uptake were largely unaffected (IC50 12.3 μM) by SRPTEKT-Hdc in MDCK43-S368A and -S365D cells, mutations that mimic or favor dephosphorylation at S368. Together, these data indicate that SRPTEKT-Hdc is a potent inhibitor of physiological Ca2+-wave signaling mediated specifically by the pS368 phosphorylated form of Cx43.

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