Development in oviparous reptiles requires the correct formation and function of extra-embryonic membranes in the egg. In 2017, we incubated 2583 eggs from five species of freshwater turtle during a ...long-term ecological study and opened eggs that failed to hatch. We described a previously unreported developmental anomaly: the retention of an extra-embryonic membrane around 7 turtles (1 Spiny Softshell Turtle (Apalone spinifera (Le Sueur, 1827)), 1 Snapping Turtle (Chelydra serpentina (Linnaeus, 1758)), and 5 Northern Map Turtles (Graptemys geographica (Le Sueur, 1817))) that were alive but unhatched >14 days after their clutch mates had emerged. We investigated the association between retention of this membrane and the exhibition of other developmental deformities of varying severity, and we tested whether this novel abnormality was associated with reduced fertility or hatching success in affected clutches. Consultation of ∼150 years of literature suggests that we observed persistence of the chorioallantoic membrane (CAM; also called the chorioallantois). Our data suggest that clutches where at least one turtle exhibits a persistent CAM may also exhibit slightly reduced fertility or hatch success in the rest of the clutch compared with conspecific clutches that do not contain this anomaly. Future research should investigate the factors predicting CAM retention and other developmental abnormalities.
Blow fly (Diptera: Calliphoridae) larvae are commonly used in forensic cases to determine postmortem intervals using development rates and successional changes in community composition. Studies are ...conducted from different regions to provide these data. We wanted to know how widely applicable these data are. We examined whether urbanized landscapes have distinct urban blow fly communities or whether the community composition in urbanized areas is simply a variation of that found in the surrounding habitat or ecozone. Using liver baited traps, we sampled 7,272 flies from 32 sites across Canada and used mapping analysis to assess urban and rural landcover classifications, and compared urban and rural species abundance and composition. Blow fly species communities from urban areas across Canada were made up of similar species and differed from the communities found in nearby rural sites. Trapping at rural sites caught more blow flies compared with urban sites (mean flies/site 59.5 and 12.4). Of the 14 species caught, 8 were caught at urban sites, 61% of these being Cynomya cadaverina Robineau-Desvoidy, 14% Phormia regina Meigen, and 11% Lucilia sericata (Meigen). In rural sites, all 14 species were caught, 41% of specimens caught were P. regina, 21% C. cadaverina, 10% Calliphora vomitoria (Linnaeus), with only 4% L. sericata. These data suggest that regional studies are appropriate for forensic entomology applications in urban landscapes, given the similar trends across Canada, less so for wilderness or rural landscapes.
Preeclampsia (PE) is characterized by maternal hypertension and placental dysfunction, often leading to fetal growth restriction (FGR). It is associated with an overexpression of the anti-angiogenic ...sFLT1 protein, which originates from the placenta and serves as a clinical biomarker to predict PE. To analyze the impact of sFLT1 on placental function and fetal growth, we generated transgenic mice with placenta-specific human sFLT1 (hsFLT1) overexpression. Immunohistochemical, morphometrical, and molecular analyses of the placentas on 14.5 dpc and 18.5 dpc were performed with a focus on angiogenesis, nutrient transport, and inflammation. Additionally, fetal development upon placental hsFLT1 overexpression was investigated. Dams exhibited a mild increase in serum hsFLT1 levels upon placental hsFLT1 expression and revealed growth restriction of the fetuses in a sex-specific manner. Male FGR fetuses expressed higher amounts of placental
mRNA compared to females. FGR placentas displayed an altered morphology, hallmarked by an increase in the spongiotrophoblast layer and changes in labyrinthine vascularization. Further, FGR placentas showed a significant reduction in placental glycogen storage and nutrient transporter expression. Moreover, signs of hypoxia and inflammation were observed in FGR placentas. The transgenic spongiotrophoblast-specific hsFLT1 mouse line demonstrates that low hsFLT1 serum levels are sufficient to induce significant alterations in fetal and placental development in a sex-specific manner.
Abstract
This paper explores how management and organization research has shed light on the relation between standards and power. The narrative literature review intersects so far unconnected ...categorizations from standardization and power literatures to systematically map out the broad knowledge structure of the power‐related literature on standardization. As a result, the paper details six power‐related notions of standardization. Building on the review, the paper summarizes neglected issues and suggests new avenues for future research. The analysis reveals that research widely tends toward either/or conceptions in terms of the empowering or disempowering dynamics of standardization. To descend from this dichotomous perspective in future research, the paper finally recommends exploring the dialectics of standardization in more detail: first, by analyzing standards as a reflection of existing power structures and contestations; second, by investigating standards as subject to power logics and interests; and third, by scrutinizing standardization as the dynamic interplay of powerlessness and powerfulness.
The project "Barrierfree dEsign foR Teaching and Learning" (BERTL) aims to identify and reduce barriers in teaching, with a focus on Universal Design or Design for All. BERTL includes an analysis of ...the situation at the University, to identify barriers faced by people with disabilities, chronic diseases, and in different life situations The BERTL Simulation Lab and Toolbox will be developed based on the analysis to help identify and eliminate barriers in their courses, and the continuing education program. In the different phases of the project, pilot courses with different didactic concepts are analyzed, checked for barriers in teaching materials and course procedures also peer feedbacks are conducted. These results will be used to improve and expand the courses of the University Applied Science and the used didactic principles. Establishing a handbook and a training series at the University is also aim of this project as practice collection and sample courses to support lecturers. The project results will be used in teaching and made publicly available.
Summary
Pain is the main complication of sickle cell disease (SCD). Individuals with SCD experience acute pain episodes and chronic daily pain, both of which are managed with opioids. Opioids have ...deleterious side effects and use‐associated stigma that make them less than ideal for SCD pain management. After recognizing the neuropathic qualities of SCD pain, clinically‐approved therapies for neuropathic pain, including gabapentin, now present unique non‐opioid based therapies for SCD pain management. These experiments explored the efficacy of gabapentin in relieving evoked and spontaneous chronic pain, and hypoxia/reoxygenation (H/R)‐induced acute pain in mouse models of SCD. When administered following H/R, a single dose of gabapentin alleviated mechanical hypersensitivity in SCD mice by decreasing peripheral fibre activity. Gabapentin treatment also alleviated spontaneous ongoing pain in SCD mice. Longitudinal daily administration of gabapentin failed to alleviate H/R‐induced pain or chronic evoked mechanical, cold or deep tissue hypersensitivity in SCD mice. Consistent with this observation, voltage‐gated calcium channel (VGCC) α2δ1 subunit expression was similar in sciatic nerve, dorsal root ganglia and lumbar spinal cord tissue from SCD and control mice. Based on these data, gabapentin may be an effective opioid alternative for the treatment of chronic spontaneous and acute H/R pain in SCD.
Approximately one-third of individuals with sickle cell disease (SCD) develop chronic pain. This debilitating pain is inadequately treated because the underlying mechanisms driving the pain are ...poorly understood. In addition to persistent pain, patients with SCD are also in a tonically proinflammatory state. Previous studies have revealed that there are elevated plasma levels of many inflammatory mediators including chemokine (c-c motif) ligand 2 (CCL2) in individuals with SCD. Using a transgenic mouse model of SCD, we investigated the contributions of CCL2 signaling to SCD-related pain. Inhibition of chemokine receptor 2 (CCR2), but not CCR4, alleviated the behavioral mechanical and cold hypersensitivity in SCD. Furthermore, acute CCR2 blockade reversed both the behavioral and the in vitro responsiveness of sensory neurons to an agonist of TRPV1, a neuronal ion channel previously implicated in SCD pain. These results provide insight into the immune-mediated regulation of hypersensitivity in SCD and could inform future development of analgesics or therapeutic measures to prevent chronic pain.
Leeches have a worldwide distribution, yet numerous geographical regions remain to be adequately surveyed. Here, we present leech species records for one of these regions: the far north of Ontario, ...Canada. This region is primarily wetland habitat and includes two of Ontario's three ecozones. Morphological examinations, as well as a single instance of successful DNA amplification with subsequent molecular identification, allowed us to identify representatives of 12 species from two predatory families (Erpobdellidae and Haemopidae) and one parasitic family (Glossiphoniidae) among samples of 130 individuals. To provide a more inclusive list of species records for this remote region, our data were also augmented by 25 largely unpublished collection records (for 102 individuals) from the Canadian Museum of Nature, which revealed the presence of an additional species. We comment on finds of particular interest in our sampling with comparison to relevant literature and provide new distribution data for these species.
Protophormia terraenovae (Robineau‐Desvoidy) (Diptera: Calliphoridae) and Phormia regina (Meigen) (Diptera: Calliphoridae) are morphologically similar blow fly species commonly used for estimating ...postmortem intervals. Field collection and storage of adults can result in color changes, in particular on calypters and palps; often collected specimens show damage such as wing fray or fungal growth. We measured the frons width: total head width ratio using photographs (ImageJ version 1.49) to differentiate these two species. Both sexes were distinguishable to species, with the greatest difference between males: 12.34% P. terraenovae versus 1.62% P. regina, less so for females: 40.25% P. terraenovae, versus 33.65% P. regina. Incorporating this feature into future blow fly keys would help with distinguishing field‐caught specimens when other features are obstructed.
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