334 research outputs found
An improved method for isolation of RNA from bone
<p>Abstract</p> <p>Background</p> <p>Bone physiology is increasingly appreciated as an important contributor to metabolic disorders such as type 2 diabetes. However, progress in understanding the role of bone in determining metabolic health is hampered by the well-described difficulty of obtaining high quality RNA from bone for gene expression analysis using the currently available approaches.</p> <p>Results</p> <p>We developed a simple approach to isolate bone RNA that combines pulverizing the bone and the phenol-guanidinium based RNA extraction in a single step while maintaining near-freezing temperatures. This single step method increases the yield of high quality RNA by eight-fold, with RNA integrity numbers ranging from 6.7 to 9.2.</p> <p>Conclusions</p> <p>Our streamlined approach substantially increases the yield of high-quality RNA from bone tissue while facilitating safe and efficient processing of multiple samples using readily available platforms. The RNA obtained from this method is suitable for use in gene expression analysis in real-time quantitative PCR, microarray, and next generation sequencing applications.</p
"Data-Based Project and Analysis"
Curatorial note from Digital Pedagogy in the Humanities: Like Melanie Feinbergâs course, this course usefully engages with information as authored by explicitly asking students to first understand and then to intervene in existing systems or processes in order to create an argument. However, while Feinbergâs course focuses on a specific aspect of information systems (metadata) and a specific theoretical concept (residuality), Kleinâs course asks students to discover and articulate their own interests, which might range from forms of visualization to formats of data and from epistemological issues to the social or political. Whether producing a proof-of-concept or proposal, students must think about how their critical arguments intersect with real-world constraints. Projects such as Nicholas Feltonâs personal annual reports are especially valuable objects to consider, as they represent uses of data that are personal and emerging, open to a variety of arguments and interventions, as well as concrete and specific, realized in specific technologies that are available to students. One of the interesting tensions running through the assignments collected here is between information as crafted by individuals and information as structured by distributed technical systems and tools, and one of the key pedagogical uses of Kleinâs project is in having students experience and negotiate this tension
The ubiquitin ligase Siah2 regulates obesity-induced adipose tissue inflammation
© 2015 The Obesity Society. Objective Chronic, low-grade adipose tissue inflammation associated with adipocyte hypertrophy is an important link in the relationship between obesity and insulin resistance. Although ubiquitin ligases regulate inflammatory processes, the role of these enzymes in metabolically driven adipose tissue inflammation is relatively unexplored. Herein, the effect of the ubiquitin ligase Siah2 on obesity-related adipose tissue inflammation was examined. Methods Wild-type and Siah2KO mice were fed a low- or high-fat diet for 16 weeks. Indirect calorimetry, body composition, and glucose and insulin tolerance were assayed along with glucose and insulin levels. Gene and protein expression, immunohistochemistry, adipocyte size distribution, and lipolysis were also analyzed. Results Enlarged adipocytes in obese Siah2KO mice were not associated with obesity-induced insulin resistance. Proinflammatory gene expression, stress kinase signaling, fibrosis, and crown-like structures were reduced in the Siah2KO adipose tissue, and Siah2KO adipocytes were more responsive to insulin-dependent inhibition of lipolysis. Loss of Siah2 increased expression of PPARγ target genes involved in lipid metabolism and decreased expression of proinflammatory adipokines regulated by PPARγ. Conclusions Siah2 links adipocyte hypertrophy with adipocyte dysfunction and recruitment of proinflammatory immune cells to adipose tissue. Selective regulation of PPARγ activity is a Siah2-mediated mechanism contributing to obesity-induced adipose tissue inflammation
Killer instincts: natural killer cells as multifactorial cancer immunotherapy
Natural killer (NK) cells integrate heterogeneous signals for activation and inhibition using germline-encoded receptors. These receptors are stochastically co-expressed, and their concurrent engagement and signaling can adjust the sensitivity of individual cells to putative targets. Against cancers, which mutate and evolve under therapeutic and immunologic pressure, the diversity for recognition provided by NK cells may be key to comprehensive cancer control. NK cells are already being trialled as adoptive cell therapy and targets for immunotherapeutic agents. However, strategies to leverage their naturally occurring diversity and agility have not yet been developed. In this review, we discuss the receptors and signaling pathways through which signals for activation or inhibition are generated in NK cells, focusing on their roles in cancer and potential as targets for immunotherapies. Finally, we consider the impacts of receptor co-expression and the potential to engage multiple pathways of NK cell reactivity to maximize the scope and strength of antitumor activities
A New Spontaneously Transformed Syngeneic Model of High-Grade Serous Ovarian Cancer with a Tumor-Initiating Cell Population
Improving screening and treatment options for patients with epithelial ovarian cancer has been a major challenge in cancer research. Development of novel diagnostic and therapeutic approaches, particularly for the most common subtype, high-grade serous ovarian cancer (HGSC), has been hampered by controversies over the origin of the disease and a lack of spontaneous HGSC models to resolve this controversy. Over long-term culture in our laboratory, an ovarian surface epithelial (OSE) cell line spontaneously transformed OSE (STOSE). The objective of this study was to determine if the STOSE cell line is a good model of HGSC. STOSE cells grow faster than early passage parental M0505 cells with a doubling time of 13 and 48âh, respectively. STOSE cells form colonies in soft agar, an activity for which M0505 cells have negligible capacity. Microarray analysis identified 1755 down-regulated genes and 1203 up-regulated genes in STOSE compared to M0505 cells, many associated with aberrant Wnt/ÎČ-catenin and Nf-ÎșB signaling. Upregulation of Ccnd1 and loss of Cdkn2a in STOSE tumors is consistent with changes identified in human ovarian cancers by The Cancer Genome Atlas. Intraperitoneal injection of STOSE cells into severe combined immunodeficient and syngeneic FVB/N mice produced cytokeratin+, WT1+, inhibinâ, and PAX8+ tumors, a histotype resembling human HGSC. Based on evidence that a SCA1+ stem cell-like population exists in M0505 cells, we examined a subpopulation of SCA1+ cells that is present in STOSE cells. Compared to SCA1â cells, SCA1+ STOSE cells have increased colony-forming capacity and form palpable tumors 8âdays faster after intrabursal injection into FVB/N mice. This study has identified the STOSE cells as the first spontaneous murine model of HGSC and provides evidence for the OSE as a possible origin of HGSC. Furthermore, this model provides a novel opportunity to study how normal stem-like OSE cells may transform into tumor-initiating cells
Combined inhibition of BCL-2 and MCL-1 overcomes BAX deficiency-mediated resistance of TP53-mutant acute myeloid leukemia to individual BH3 mimetics
TP53-mutant acute myeloid leukemia (AML) respond poorly to currently available treatments, including venetoclax-based drug combinations and pose a major therapeutic challenge. Analyses of RNA sequencing and reverse phase protein array datasets revealed significantly lower BAX RNA and protein levels in TP53-mutant compared to TP53-wild-type (WT) AML, a finding confirmed in isogenic CRISPR-generated TP53-knockout and -mutant AML. The response to either BCL-2 (venetoclax) or MCL-1 (AMG176) inhibition was BAX-dependent and much reduced in TP53-mutant compared to TP53-WT cells, while the combination of two BH3 mimetics effectively activated BAX, circumventing survival mechanisms in cells treated with either BH3 mimetic, and synergistically induced cell death in TP53-mutant AML and stem/progenitor cells. The BH3 mimetic-driven stress response and cell death patterns after dual inhibition were largely independent of TP53 status and affected by apoptosis induction. Co-targeting, but not individual targeting of BCL-2 and MCL-1 in mice xenografted with TP53-WT and TP53-R248W Molm13 cells suppressed both TP53-WT and TP53-mutant cell growth and significantly prolonged survival. Our results demonstrate that co-targeting BCL-2 and MCL-1 overcomes BAX deficiency-mediated resistance to individual BH3 mimetics in TP53-mutant cells, thus shifting cell fate from survival to death in TP53-deficient and -mutant AML. This concept warrants clinical evaluation
Exploration of Burnout, Emotional Thriving, and Emotional Recovery in an Academic Medical Center: a Mixed Methods Quality Improvement Project
Introduction: Healthcare provider burnout, an indicator of wellbeing, impacts patient safety, provider distress, and employee turnover. In this mixed methods, multi-site quality improvement study conducted \u3c6 months prior to the start of the COVID-19 pandemic, we assessed employee wellbeing in a large clinical department.
Methods: Wellbeing surveys were sent electronically to Department of Medicine clinicians, researchers, administrators, and staff from August-September 2019 assessing perceptions of Burnout, Emotional Thriving (ET), and Emotional Recovery (ER). Qualitative responses were reviewed for themes using mixed inductive-deductive analysis. The initial coding was done by small teams with consensus obtained through large group discussions. This study was IRB-approved as non-human subjects research.
Results: Of the 671 respondents, 54% met criteria for burnout (Burnout+), 65% for ER (ER+), and 61% for ET (ET+). ER+ and ET+ were present in nearly half of Burnout+ respondents (53% and 43% respectively). Several themes emerged in the qualitative analysis: workload and expectations; tangible resources; work culture; and salary/benefits, with leadership influencing each of the domains.
Conclusion: Burnout, ET, and ER can co-exist within the same individual. Employee wellbeing is not adequately reflected by the binary of whether or not an individual is experiencing burnout. All employees at academic medical centers, including staff, researchers, and clinicians, are vulnerable to the same workplace factors driving burnout. Our findings have been used to target areas of intervention during the COVID-19 pandemic at our institution. We propose that other academic medical centers may have similar workplace stressors that they could assess and target for improvement
Defining Ecological Drought for the Twenty-First Century
THE RISING RISK OF DROUGHT. Droughts of the twenty-first century are characterized by hotter temperatures, longer duration, and greater spatial extent, and are increasingly exacerbated by human demands for water. This situation increases the vulnerability of ecosystems to drought, including a rise in drought-driven tree mortality globally (Allen et al. 2015) and anticipated ecosystem transformations from one state to anotherâfor example, forest to a shrubland (Jiang et al. 2013). When a drought drives changes within ecosystems, there can be a ripple effect through human communities that depend on those ecosystems for critical goods and services (Millar and Stephenson 2015). For example, the âMillennium Droughtâ (2002â10) in Australia caused unanticipated losses to key services provided by hydrological ecosystems in the MurrayâDarling basinâincluding air quality regulation, waste treatment, erosion prevention, and recreation. The costs of these losses exceeded AUD $800 million, as resources were spent to replace these services and adapt to new drought-impacted ecosystems (Banerjee et al. 2013). Despite the high costs to both nature and people, current drought research, management, and policy perspectives often fail to evaluate how drought affects ecosystems and the ânatural capitalâ they provide to human communities. Integrating these human and natural dimensions of drought is an essential step toward addressing the rising risk of drought in the twenty-first century
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