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991.
Denise Campbell-Scherer Yvonne Chiu Nicole Naadu Ofosu Thea Luig Karen Heather Hunter Badi Jabbour Sauleha Farooq Ali Mahdi Aline Gayawira Fransiska Awasis Funke Olokude Hannah Goa Hina Syed Judy Sillito Lydia Yip Lyn Belle Mawien Akot Monique Nutter Nadia Farhat Yan Wang Niga Jalal Saida Khalif Shiva Chapagain Stephanie Fernandez Susan Azarcon Zhewar Hama 《CMAJ》2021,193(31):E1203
BACKGROUND:The COVID-19 pandemic has exacerbated disparities in poverty and illness for people in vulnerable circumstances in ethnocultural communities. We sought to understand the evolving impacts of COVID-19 on ethnocultural communities to inform intersectoral advocacy and community action.METHODS:The Illuminate Project used participatory action research, with cultural health brokers as peer researchers, from Sept. 21 to Dec. 31, 2020, in Edmonton, Alberta. Twenty-one peer researchers collected narratives from members of ethnocultural communities and self-interpreted them as they entered the narratives into the SenseMaker platform, a mixed-method data collection tool. The entire research team analyzed real-time, aggregate, quantitative and qualitative data to identify emerging thematic domains, then visualized these domains with social network analysis.RESULTS:Brokers serving diverse communities collected 773 narratives. Identified domains illuminate the evolving and entangled impacts of COVID-19 including the following: COVID-19 prevention and management; care of acute, chronic and serious illnesses other than COVID-19; maternal care; mental health and triggers of past trauma; financial insecurity; impact on children and youth and seniors; and legal concerns. We identified that community social capital and cultural brokering are key assets that facilitate access to formal health and social system supports.INTERPRETATION:The Illuminate Project has illustrated the entangled, systemic issues that result in poor health among vulnerable members of ethnocultural communities, and the exacerbating effects of COVID-19, which also increased barriers to mitigation. Cultural brokering and community social capital are key supports for people during the COVID-19 pandemic. These findings can inform policy to reduce harm and support community resiliency.Mahatma Gandhi observed that “the true measure of any society can be found in how it treats its most vulnerable members.” Ethnocultural communities, defined by their unique shared characteristics (e.g., cultural traditions, language, country of origin),1 face greater challenges and have higher rates of poverty and illness than the general Canadian population. Migration results in conditions that affect all social determinants of health and disproportionally affect health outcomes, herein referred to as vulnerable circumstances.2,3 The emergence of major outbreaks of SARS-CoV-2 infections in ethnocultural communities highlights both the vulnerable circumstances of these communities and the disparities they face in accessing high-quality, culturally appropriate information and support.4–7 Studies have shown substantial variation in deaths attributed to COVID-19 based on factors such as age, sex, ethnicity, length of time in Canada, income and education.8–11 However, given the well-known gap in reporting comprehensive COVID-19 data in relation to race and ethnicity, efforts to measure its impact are hampered.8–12 There is an urgent need to understand the evolving challenges of COVID-19 to inform action and public policy that can mitigate these challenges.To understand evolving situations of complexity and crisis, sensemaking, defined as “a continuous process to establish situational awareness,”13 is a crucial undertaking.14 Using participatory action research,15–18 we sought to understand the evolving impacts of COVID-19 on ethnocultural communities to inform broader national efforts to migitate the impacts of COVID-19. Particularly, we sought to understand how the challenges of COVID-19 are entangled with contextual factors at multiple levels, how families and communities are leveraging strengths and social capital to adapt, and the role of cultural brokers in managing the crisis. 相似文献
992.
Myeng Chan Hong Yun Kyung Kim Jae Yong Choi Si Qiang Yang Hakjune Rhee Young Hoon Ryu Tae Hyun Choi Gi Jeong Cheon Gwang Il An Hye Yun Kim Youngsoo Kim Dong Jin Kim Jun-Seok Lee Young-Tae Chang Kyo Chul Lee 《Bioorganic & medicinal chemistry》2010,18(22):7724-7730
Fluorescence probes that can detect Aβ (β-amyloid peptide) plaque are important tools for diagnosis of Alzheimer’s disease (AD), and 4-N-methylamino-4′-hydroxystilbene (SB-13) is one of the promising candidate molecules. We report here the synthesis of SB-13 derivatives that consist of various electron donating/withdrawing moieties and distinct size of N-substituents. The synthesized compounds were screened for detection of Aβ40 fibrils in vitro. Four compounds exhibited more than sixfold intensity increase, and they were further analyzed for detail bindings and Aβ plaque imaging. Among these molecules, compound 42 meets two critical requirements for imaging agent; high fluorescence responsiveness and strong binding affinity. This compound showed more than 25-fold increase with the dissociation constant of 1.13 ± 0.37 μM. In AD mouse brain tissue, 42 selectively stained Aβ plaque, more specifically peripheral regions of Aβ plaque. This finding demonstrated its potential use as brain-imaging agents for AD studies. 相似文献
993.
Michelle Hannah 《The Australian journal of anthropology》2010,21(3):332-349
Recent global linkages have brought about increased cross‐cultural encounters between diverse Buddhist groups. While this often results in rich, rewarding relationships, it has also resulted in cross‐cultural tensions. This article examines disputes that arose between diverse groups of Buddhists during international Buddhist conferences about proposals to introduce full ordination for Tibetan Buddhist nuns. I argue that this debate and conflict is largely the result of globalisation and the resultant interactions between indigenous Buddhists and western converts and, in turn, western moral discourses and feminisms. 相似文献
994.
Ikhlas S. Ahmed Hannah J. Rohe Katherine E. Twist Rolf J. Craven 《The Journal of biological chemistry》2010,285(32):24775-24782
Tumorigenesis requires the concerted action of multiple pathways, including pathways that stimulate proliferation and metabolism. Epidermal growth factor receptor (EGFR) is a transmembrane receptor-tyrosine kinase that is associated with cancer progression, and the EGFR inhibitors erlotinib/tarceva and tyrphostin/AG-1478 are potent anti-cancer therapeutics. Pgrmc1 (progesterone receptor membrane component 1) is a cytochrome b5-related protein that is up-regulated in tumors and promotes cancer growth. Pgrmc1 and its homologues have been implicated in cell signaling, and we show here that Pgrmc1 increases susceptibility to AG-1478 and erlotinib, increases plasma membrane EGFR levels, and co-precipitates with EGFR. Pgrmc1 co-localizes with EGFR in cytoplasmic vesicles and co-fractionates with EGFR in high density microsomes. The findings have therapeutic potential because a Pgrmc1 small molecule ligand, which inhibits growth in a variety of cancer cell types, de-stabilized EGFR in multiple tumor cell lines. EGFR is one of the most potent receptor-tyrosine kinases driving tumorigenesis, and our data support a role for Pgrmc1 in promoting several cancer phenotypes at least in part by binding EGFR and stabilizing plasma membrane pools of the receptor. 相似文献
995.
Markus Wirtz Hannah Birke Corinna Heeg Christopher Müller Fabian Hosp Christian Throm Stephan K?nig Anna Feldman-Salit Karsten Rippe Gabriele Petersen Rebecca C. Wade Vladimir Rybin Klaus Scheffzek Rüdiger Hell 《The Journal of biological chemistry》2010,285(43):32810-32817
Cysteine synthesis in bacteria and plants is catalyzed by serine acetyltransferase (SAT) and O-acetylserine (thiol)-lyase (OAS-TL), which form the hetero-oligomeric cysteine synthase complex (CSC). In plants, but not in bacteria, the CSC is assumed to control cellular sulfur homeostasis by reversible association of the subunits. Application of size exclusion chromatography, analytical ultracentrifugation, and isothermal titration calorimetry revealed a hexameric structure of mitochondrial SAT from Arabidopsis thaliana (AtSATm) and a 2:1 ratio of the OAS-TL dimer to the SAT hexamer in the CSC. Comparable results were obtained for the composition of the cytosolic SAT from A. thaliana (AtSATc) and the cytosolic SAT from Glycine max (Glyma16g03080, GmSATc) and their corresponding CSCs. The hexameric SAT structure is also supported by the calculated binding energies between SAT trimers. The interaction sites of dimers of AtSATm trimers are identified using peptide arrays. A negative Gibbs free energy (ΔG = −33 kcal mol−1) explains the spontaneous formation of the AtCSCs, whereas the measured SAT:OAS-TL affinity (KD = 30 nm) is 10 times weaker than that of bacterial CSCs. Free SAT from bacteria is >100-fold more sensitive to feedback inhibition by cysteine than AtSATm/c. The sensitivity of plant SATs to cysteine is further decreased by CSC formation, whereas the feedback inhibition of bacterial SAT by cysteine is not affected by CSC formation. The data demonstrate highly similar quaternary structures of the CSCs from bacteria and plants but emphasize differences with respect to the affinity of CSC formation (KD) and the regulation of cysteine sensitivity of SAT within the CSC. 相似文献
996.
Elisabeth C. Lowe Sarah Bydder Robert S. Hartshorne Hannah L. U. Tape Elizabeth J. Dridge Charles M. Debieux Konrad Paszkiewicz Ian Singleton Richard J. Lewis Joanne M. Santini David J. Richardson Clive S. Butler 《The Journal of biological chemistry》2010,285(24):18433-18442
Selenate reductase (SER) from Thauera selenatis is a periplasmic enzyme that has been classified as a type II molybdoenzyme. The enzyme comprises three subunits SerABC, where SerC is an unusual b-heme cytochrome. In the present work the spectropotentiometric characterization of the SerC component and the identification of redox partners to SER are reported. The mid-point redox potential of the b-heme was determined by optical titration (Em + 234 ± 10 mV). A profile of periplasmic c-type cytochromes expressed in T. selenatis under selenate respiring conditions was undertaken. Two c-type cytochromes were purified (∼24 and ∼6 kDa), and the 24-kDa protein (cytc-Ts4) was shown to donate electrons to SerABC in vitro. Protein sequence of cytc-Ts4 was obtained by N-terminal sequencing and liquid chromatography-tandem mass spectrometry analysis, and based upon sequence similarities, was assigned as a member of cytochrome c4 family. Redox potentiometry, combined with UV-visible spectroscopy, showed that cytc-Ts4 is a diheme cytochrome with a redox potential of +282 ± 10 mV, and both hemes are predicted to have His-Met ligation. To identify the membrane-bound electron donors to cytc-Ts4, growth of T. selenatis in the presence of respiratory inhibitors was monitored. The specific quinol-cytochrome c oxidoreductase (QCR) inhibitors myxothiazol and antimycin A partially inhibited selenate respiration, demonstrating that some electron flux is via the QCR. Electron transfer via a QCR and a diheme cytochrome c4 is a novel route for a member of the DMSO reductase family of molybdoenzymes. 相似文献
997.
998.
Hannah S. Rhee Joseph F.Y. Hoh 《The journal of histochemistry and cytochemistry》2010,58(12):1057-1065
This work uses cross-innervation of respiratory muscles of different developmental origins to probe myogenic and neurogenic mechanisms regulating their fiber types. The thyroarytenoid (TA) originates from the sixth branchial arch, whereas the sternohyoid (SH) is derived from somitic mesoderm. Immunohistochemical analysis using highly specific monoclonal antibodies to myosin heavy chain (MyHC) isoforms reveals that normal rat SH comprises slow, 2a, 2x, and 2b fibers, as in limb fast muscles, whereas the external division of the TA has only 2b/eo fibers coexpressing 2B and extraocular (EO) MyHCs. Twelve weeks after cross-innervation with the recurrent laryngeal nerve, the SH retained slow and 2a fibers, greatly increased the proportion of 2x fibers, and their 2b fibers failed to express EO MyHC. In the cross-innervated TA, the SH nerve failed to induce slow and 2A MyHC expression and failed to suppress EO MyHC expression in 2b/eo fibers. However, 2x fibers amounting to 4.2% appeared de novo in the external division of the TA. We conclude that although MyHC gene expression in these muscles can be modulated by neural activity, the patterns of response to altered innervation are largely myogenically determined, thus supporting the idea that SH and TA differ in muscle allotype. (J Histochem Cytochem 58:1057–1065, 2010) 相似文献
999.
Polycystin (PC)1 and PC2 are membrane proteins implicated in autosomal dominant polycystic kidney disease. A physiologically relevant cleavage at PC1's G protein-coupled receptor proteolytic site (GPS) occurs early in the secretory pathway. Our results suggest that PC2 increases both PC1 GPS cleavage and PC1's appearance at the plasma membrane. Mutations that prevent PC1's GPS cleavage prevent its plasma membrane localization. PC2 is a member of the trp family of cation channels and is an important PC1 binding partner. The effect of PC2 on PC1 localization is independent of PC2 channel activity, as tested using channel-inhibiting PC2 mutations. PC1 and PC2 can interact through their C-terminal tails, but removing the C-terminal tail of either protein has no effect on PC1 surface localization in human embryonic kidney 293 cells. Experiments in polarized LLC-PK cells show that apical and ciliary PC1 localization requires PC2 and that this delivery is sensitive to PC2 truncation. In sum, our work shows that PC2 expression is required for the movement of PC1 to the plasma and ciliary membranes. In fibroblast cells this localization effect is independent of PC2's channel activity or PC1 binding ability but involves a stimulation of PC1's GPS cleavage before the PC1 protein's surface delivery. 相似文献
1000.
Diversity of endophytic bacteria in ginseng and their potential for plant growth promotion 总被引:1,自引:0,他引:1
Endophytic bacteria have been found in virtually every plant studied, where they colonize the internal tissues of their host
plant and can form a range of different beneficial relationships. The diversity of bacterial endophytes associated with ginseng
plants of varying age levels in Korea was investigated. Fifty-one colonies were isolated from the interior of ginseng stems.
Although a mixed composition of endophyte communities was recovered from ginseng based on the results of 16S rDNA analysis,
bacteria of the genus Bacillus and Staphylococcus dominated in 1-year-old and 4-year-old plants, respectively. Phylogenetic analysis revealed four clusters: Firmicutes, Actinobacteria, α-Proteobacteria, and γ-Proteobacteria, with Firmicutes being predominant. To evaluate the plant growth promoting activities, 18 representative isolates were selected. Amplification
of nifH gene confirmed the presence of diazotrophy in only two isolates. Half of the isolates solubilized mineral phosphate. Except
four, all the other endophytic isolates produced significant amounts of indole acetic acid in nutrient broth. Iron sequestering
siderophore production was detected in seven isolates. Isolates E-I-3 (Bacillus megaterium), E-I-4 (Micrococcus luteus), E-I-8 (B. cereus), and E-I-20 (Lysinibacillus fusiformis) were positive for most of the plant growth promoting traits, indicating their role in growth promotion of ginseng. 相似文献