793 research outputs found
Twisted [(R3P)PdX] groups above dicarbaborane ligands: 4-dimethylsulfido-3-iodo-3-triphenylphosphine-closo-3-pallada-1,2-dicarbadodecaborane and 3-dimethylphenylphosphine-3-chloro-4-dimethylsulfido-closo-3-pallada-1,2-dicarbadodecaborane
The structural analyses of [3-(PPh₃)-3-I-4-(SMe₂)-closo-3,1,2-PdC₂B₉H₁₀] or [Pd(C₄H₁₆B₉S)I(C₁₈H₁₅P)], (I), and [3-(PPhMe₂)-3-Cl-4-(SMe₂)-closo-3,1,2-PdC₂B₉H₁₀] or [Pd(C₄H₁₆B₉S)Cl(C₈H₁₁P)], (II), show that in comparison with [3-(PR₃)2-closo-3,1,2-PdC₂B₉H₁₁] the presence of the 4-SMe₂ group causes the [PdX(PR₃)] unit (X = halogen) to twist about an axis passing through the Pd atom and the directly opposite B atom of the carbaborane ligand. The halogen atoms are located almost directly above a C atom in the C₂B₃ face, and the conformations of the [PdX(PR₃)] units above the C₂B₃ faces are not those predicted from molecular orbital calculations of the closo-3,1,2-PdC₂B₉ system. The fact that the variation from the predicted conformation is greater in the case of (I) than in (II) may be ascribed to the greater steric interactions induced by the I atom in (I) compared with the Cl atom in (II)
Conditioning and Habituation of White-Tailed Deer to Two Common Deterrents
It was hypothesized white-tailed deer (Odocoileus virginianus) could be readily conditioned to 2 commonly used deterrents, Deer-Away® Big Game Repellent (BGR) and blood meal (BM). Plots were randomly assigned BGR, BM and control. Free-ranging deer were initially conditioned to forage for corn at each 49m 2 bare earth plots delivered at 0500 hr and 1600 hr by programmable siing-type feeders. Hoof prints were counted within a 3.7m 2 sample area of each plot to quantify activity. Following preconditioning, data were collected during 5, 5-day periods. Application of BGR and BM to their respective bare earth plots occurred during periods 2, 4 and 5. Initial exposure decreased the number of hoof-prints for BGR (P = 0.011) and BM (P = 0.033) compared to the control. Subsequent exposure to BGR during periods 4 and 5 did not differ from the control (P \u3e 0.227). Prints counted following exposure to BM were similar to the control in period 4 (P = 0.267), but lower (P = 0.045) in period 5. Within each treatment group , prints counted were lower during period 2 compared to periods 1, 3, 4 and 5 for both BGR (P =0.001) and BM (P = 0.018). No differences (P \u3e 0.05) were found among periods 1,3,4 and 5 within each treatment. Results support the hypothesis that white-tailed deer can readily be conditioned to these two commonly used deterrents
Developing a recovery college: a preliminary exercise in establishing regional readiness and community needs
peer-reviewedBackground: Recovery orientated intervention has experienced a paradigm shift towards stakeholder training and education within recovery colleges. Such colleges are typicallyunderpinned by a culture of emancipatory education that aims to facilitate recovery through educational choice.Aims: The study aims to establish regional readiness for a recovery college. Specifically, we aim to uncover key stakeholder attitudes towards recovery, outline a contextual conceptualization of recovery and show how inductive, community-based research can incorporate stakeholderviews with core fidelity markers of a recovery college.Method: A mixed methods approach, specifically a cross-sectional survey, was adopted tointersect quantitative scales of stakeholder attitudes and qualitative assessment of recovery concepts and community needs.Results: Stakeholders recovery attitudes were positive overall with some variation between participant groups. Concepts of recovery were developing independent abilities, establishing connectedness to support and as a journey. The needs cited by the stakeholders were largely correlated with the core fidelity markers of a recovery college.Conclusion: A community psychology approach offers a means to ascertain regional readinessfor a recovery college, and uncover key development foci based on community needs. Werecommend that service areas adopt a similar approach when considering recovery-orientatedservice developments.ACCEPTEDpeer-reviewe
High intensity exercise as a dishabituating stimulus restores counterregulatory responses in recurrently hypoglycemic rodents
Hypoglycemia is a major adverse effect of insulin therapy for people with type 1 diabetes (T1D). Profound defects in the normal counterregulatory response to hypoglycemia explain the frequency of hypoglycemia occurrence in T1D. Defective counterregulation results to a large extent from prior exposure to hypoglycemia per se, leading to a condition called impaired awareness of hypoglycemia (IAH), the cause of which is unknown. In the current study, we investigate the hypothesis that IAH develops through a special type of adaptive memory referred to as habituation. To test this hypothesis, we used a novel intense stimulus (high-intensity exercise) to demonstrate two classic features of a habituated response, namely dishabituation and response recovery. We demonstrate that after recurrent hypoglycemia the introduction of a novel dishabituating stimulus (a single burst of high-intensity exercise) in male Sprague-Dawley rats restores the defective hypoglycemia counterregulatory response. In addition, the rats showed an enhanced response to the novel stimulus (response recovery). We make the further observation using proteomic analysis of hypothalamic extracts that high-intensity exercise in recurrently hypoglycemic rats increases levels of a number of proteins linked with brain-derived neurotrophic factor signaling. These findings may lead to novel therapeutic approaches for individuals with T1D and IAH.</jats:p
Neighborhood Factors Relevant for Walking in Older, Urban, African American Adults
Focus-group and photo-voice methodology were used to identify the salient factors of the neighborhood environment that encourage or discourage walking in older, urban African Americans. Twenty-one male (n = 2) and female (n = 19) African Americans age 60 years and older (M = 70 ± 8.7, range = 61–85) were recruited from a large urban senior center. Photographs taken by the participants were used to facilitate focus-group discussions. The most salient factors that emerged included the presence of other people, neighborhood surroundings, and safety from crime, followed by sidewalk and traffic conditions, animals, public walking tracks and trails, and weather. Future walking interventions for older African Americans should include factors that encourage walking, such as the presence of other friendly or active people, attractive or peaceful surroundings, and a sense of safety from crime
Nrf2-mediated neuroprotection response to recurrent hypoglycemia is insufficient to prevent cognitive impairment in a rodent model of type 1 diabetes
It remains uncertain whether recurrent nonsevere hypoglycemia (Hypo) results in long-term cognitive impairment in type 1 diabetes (T1D). This study tested the hypothesis that specifically in the T1D state, Hypo leads to cognitive impairment via a pathological response to oxidative stress. Wild-type (Control) and nuclear factor–erythroid 2 p45–related factor 2 (Nrf2) null mice were studied. Eight groups of mice (Control and Nrf2−/− ± T1D and ± Hypo) were subject to recurrent, twice-weekly, insulin or saline injections over 4 weeks, after which cognitive function was assessed and brain tissue analyzed. Recurrent moderate hypoglycemia in T1D, but not Control, mice significantly impaired cognitive performance, and this was associated with hippocampal oxidative damage and inflammation despite an enhanced expression of Nrf2 and its target genes Hmox1 and Nqo1. In Nrf2−/− mice, both T1D and Hypo independently resulted in impaired cognitive performance, and this was associated with oxidative cell damage and marked inflammation. Together, these data suggest that Hypo induces an Nrf2-dependent antioxidant response in the hippocampus, which counteracts oxidative damage. However, in T1D, this neuroprotective mechanism is insufficient to prevent neuronal oxidative damage, resulting in chronic deficits in working and long-term memory.</jats:p
Influenza A virus preferentially snatches noncoding RNA caps
Influenza A virus (IAV) lacks the enzyme for adding 5\u27 caps to its RNAs and snatches the 5\u27 ends of host capped RNAs to prime transcription. Neither the preference of the host RNA sequences snatched nor the effect of cap-snatching on host processes is completely defined. Previous studies of influenza cap-snatching used poly(A)-selected RNAs from infected cells or relied on annotated host genes to define the snatched host RNAs, and thus lack details on many noncoding host RNAs including snRNAs, snoRNAs, and promoter-associated capped small (cs)RNAs, which are made by paused Pol II during transcription initiation. In this study, we used a nonbiased technique, CapSeq, to identify host and viral-capped RNAs including nonpolyadenylated RNAs in the same samples, and investigated the substrate-product correlation between the host RNAs and the viral RNAs. We demonstrated that noncoding host RNAs, particularly U1 and U2, are the preferred cap-snatching source over mRNAs or pre-mRNAs. We also found that csRNAs are highly snatched by IAV. Because the functions of csRNAs remain mostly unknown, especially in somatic cells, our finding reveals that csRNAs at least play roles in the process of IAV infection. Our findings support a model where nascent RNAs including csRNAs are the preferred targets for cap-snatching by IAV and raise questions about how IAV might use snatching preferences to modulate host-mRNA splicing and transcription
Coxsackievirus-Induced Proteomic Alterations in Primary Human Islets Provide Insights for the Etiology of Diabetes
Enteroviral infections have been associated with the development of type 1 diabetes (T1D), a chronic inflammatory disease characterized by autoimmune destruction of insulin-producing pancreatic beta cells. Cultured human islets, including the insulin-producing beta cells, can be infected with coxsackievirus B4 (CVB4) and thus are useful for understanding cellular responses to infection. We performed quantitative mass spectrometry analysis on cultured primary human islets infected with CVB4 to identify molecules and pathways altered upon infection. Corresponding uninfected controls were included in the study for comparative protein expression analyses. Proteins were significantly and differentially regulated in human islets challenged with virus compared with their uninfected counterparts. Complementary analyses of gene transcripts in CVB4-infected primary islets over a time course validated the induction of RNA transcripts for many of the proteins that were increased in the proteomics studies. Notably, infection with CVB4 results in a considerable decrease in insulin. Genes/proteins modulated during CVB4 infection also include those involved in activation of immune responses, including type I interferon pathways linked to T1D pathogenesis and with antiviral, cell repair, and inflammatory properties. Our study applies proteomics analyses to cultured human islets challenged with virus and identifies target proteins that could be useful in T1D interventions
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