Epigenetic changes are associated with the regulation of transcription of key cell regulatory genes micro RNAs (miRNAs) during different types of liver injury. This study evaluated the role of ...methylation-associated miRNA, miR-34a, in alcoholic liver diseases. We identified that ethanol feeding for 4 weeks significantly up-regulated 0.8% of known miRNA compared with controls, including miR-34a. Treatment of normal human hepatocytes (N-Heps) and cholangiocytes human intrahepatic biliary epithelial cells (HiBECs) with ethanol and lipopolysaccharide induced a significant increase of miR-34a expression. Overexpression of miR-34a decreased ethanol-induced apoptosis in both N-Heps and HiBECs. In support of the concept that the 5′-promoter region of miR-34a was noted to be embedded within a CpG island, the expression level of miR-34a was significantly increased after demethylation treatment in N-Heps and HiBECs. By methylation-specific PCR, we confirmed that miR-34a activation is associated with ethanol-linked hypomethylation of the miR-34a promoter. A combination of bioinformatics, dual-luciferase reporter assay, mass spectrometry, and Western blot analysis revealed that caspase-2 and sirtuin 1 are the direct targets of miR-34a. Furthermore, modulation of miR-34a also altered expression of matrix metalloproteases 1 and 2, the mediators involved in hepatic remodeling during alcoholic liver fibrosis. These findings provide the basis for an exciting field in which the epigenomic microRNAs of hepatic cells may be manipulated with potential therapeutic benefits in human alcoholic liver diseases.
Background & Aims microRNAs (miRNAs) are a class of small noncoding RNAs that can regulate gene expression by translation repression or mRNA degradation. Our aim was to evaluate the role of ...aberrantly expressed miRNAs in hepatocellular cancer (HCC). Methods miRNA expression in HCC tissues and cells was evaluated by qPCR array and Taqman miRNA assay. Cell proliferation, motility, invasion, and the angiogenesis index were quantitated using commercial assays. DNA methylation status, matrix metalloproteinases (MMPs) mRNA expression was quantitated by real-time PCR analysis. Results miRNA profiling identified a decrease in miR-125b expression in HCC tumor tissues and cell lines. The expression of miR-125b was significantly increased by the methylation inhibitor 5-aza-2′-deoxycytidine in HCC cells but not in normal controls, suggesting that the expression of miR-125b could be epigenetically modulated. Methylation-specific PCR revealed hypermethylation status of miR-125b in HCC cells compared to non-malignant controls. Cell proliferation, anchorage-independent growth, cell migration, invasion, and angiogenesis were significantly decreased by the introduction of miR-125b precursor in HCC cell lines. Placenta growth factor was identified as a target of miR-125b by bioinformatics analysis and experimentally verified using luciferase reporter constructs. Overexpression of miR-125b in HCC cells decreased PIGF expression, and altered the angiogenesis index. Furthermore, modulation of miR-125b also distorted expression of MMP-2 and -9, the mediators of enzymatic degradation of the extracellular matrix. Conclusions Our studies showing epigenetic silencing of miR-125b contributes to an invasive phenotype provide novel mechanistic insights and identify a potential target mechanism that could be manipulated for therapeutic benefit in HCC.
Cholangiocarcinoma (CCA) is a biliary cancer arising from damaged bile ducts. Epithelial‐mesenchymal transition (EMT) occurs as epithelial cells begin to resemble mesenchymal cells leading to ...increased invasion potential as the extracellular matrix (ECM) degrades. Histamine exerts its effects by way of four receptors (H1‐H4 HRs). Clobenpropit, a potent H4HR agonist, inhibits mammary adenocarcinoma growth. We have shown that (1) cholangiocytes and CCA cells express H1‐H4 HRs and (2) the H3HR decreases CCA proliferation. We evaluated the effects of clobenpropit on CCA proliferation, invasion, EMT phenotypes, and ECM degradation. In vitro, we used CCA cell lines to study proliferation, signaling pathways, and the morphological invasive potential. Gene and protein expression of the hepatobiliary epithelial markers CK‐7, CK‐8, and CK‐19, the focal contact protein paxillin, and the mesenchymal markers fibronectin, s100A4, and vimentin were evaluated. Cell invasion across an ECM layer was quantitated and matrix metalloproteinase‐1, ‐2, ‐3, ‐9, and ‐11 gene and protein expression was examined. Evaluation of the specific role of H4HR was performed by genetic knockdown of the H3HR and overexpression of H4HR. Proliferation was evaluated by proliferating cellular nuclear antigen immunoblotting. In vivo, xenograft tumors were treated with either vehicle or clobenpropit for 39 days. Tumor volume was recorded every other day. Clobenpropit significantly decreased CCA proliferation by way of a Ca2+‐dependent pathway and altered morphological development and invasion. Loss of H3HR expression or overexpression of H4HR significantly decreased CCA proliferation. In vivo, clobenpropit inhibited xenograft tumor growth compared with controls. Conclusion: Modulation of H4HR by clobenpropit disrupts EMT processes, ECM breakdown, and invasion potential and decreases tumor growth. Interruption of tumorigenesis and invasion by histamine may add to therapeutic advances for CCAs. (HEPATOLOGY 2011;)
Functional pluripotent characteristics have been observed in specific subpopulations of hepatic cells that express some of the known cholangiocyte markers. Although evidence indicates that specific ...cytokines, granulocyte macrophage colony‐stimulating factors (GM‐CSFs), and stem cell factors (SCFs) may be candidate treatments for liver injury, the role of these cytokines in intrahepatic biliary epithelium remodeling is unknown. Thus, our aim was to characterize the specific cytokines that regulate the remodeling potentials of cholangiocytes after 70% partial hepatectomy (PH). The expression of the cytokines and their downstream signaling molecules was studied in rats after 70% PH by immunoblotting and in small and large murine cholangiocyte cultures (SMCCs and LMCCs) by immunocytochemistry and real‐time polymerase chain reaction (PCR). There was a significant, stable increase in SCF and GM‐CSF levels until 7 days after PH. Real‐time PCR analysis revealed significant increases of key remodeling molecules, such as S100 calcium‐binding protein A4 (S100A4) and miR‐181b, after SCF plus GM‐CSF administration in SMCCs. SMCCs produced significant amounts of soluble and bound SCFs and GM‐CSFs in response to transforming growth factor‐beta (TGF‐β). When SMCCs were incubated with TGF‐β plus anti‐SCF+GM‐CSF antibodies, there was a significant decrease in S100A4 expression. Furthermore, treatment of SMCCs with SCF+GM‐CSF significantly increased matrix metalloproteinases (MMP‐2 and MMP‐9) messenger RNA as well as miR‐181b expression, along with a reduction of metalloproteinase inhibitor 3. Levels of MMP‐2, MMP‐9, and miR‐181b were also up‐regulated in rat liver and isolated cholangiocytes after PH. Conclusion: Our data suggest that altered expression of SCF+GM‐CSF after PH can contribute to biliary remodeling (e.g., post‐transplantation) by functional deregulation of the activity of key signaling intermediates involved in cell expansion and multipotent differentiation. (HEPATOLOGY 2012;;55:209–221)
PURPOSETo explore self-reported musculoskeletal symptoms in radiographers registered by the American Registry of Radiologic Technologists (ARRT) in the United States. There is a gap in the literature ...focusing on the unique set of risk factors for radiographers. METHODSA subset of ARRT radiographers received an email invitation to complete an online survey that included questions about their experience with musculoskeletal symptoms and their exposure to potential risk factors for those symptoms. RESULTSOut of the 635 ARRT credentialed, nonretired radiographers who completed the survey, 81% reported experiencing pain or discomfort while performing patient cases. Through logistic regression statistical modeling, a set of 4 personal factors (including poorer perceptions of health and sleep quality), 1 work demographic factor (working in fluoroscopy), and 3 psychosocial work factors (including perceptions of higher physically demanding workload and work pressure and stress) were identified in differentiating radiographers who experience pain or discomfort when performing patient cases from those who do not. DISCUSSIONConsistent with prior research, these results indicate multiple work-related factors, including physical and psychosocial work factors, appear to be associated with the prevalence of musculoskeletal symptoms in radiographers. Ideas for addressing these risk factors are discussed, as well as opportunities for radiography managers and academics to collaborate in evaluating the effectiveness of intervention ideas when deployed in practice. CONCLUSIONAlthough this study is cross-sectional, these results can be used to inform intervention efforts, such as limiting or rotating work duties in fluoroscopy, reducing other physically demanding aspects of work, addressing understaffing, which increases work pressure in many ways, and promoting employee self-care practices.
To enhance how educators use robotics to support the development of STEM and 21st century competencies, we report findings from focus groups and interviews with 133 elementary teachers and 46 ...elementary students, 19 video-recorded classroom observations, and a teacher survey from Ontario, Canada. We find that teachers use robotics in a variety of ways to support the development of cognitive, interpersonal, and intrapersonal skills. Despite the potential benefits, our participants identified several factors that limit the adoption of robotics teaching and learning on a wider scale, including insufficient curriculum and assessment integration, resources, and professional development and support. We provide practical policy guidelines to support the broader integration of robotics and reflect on how these recommendations may inform teaching and learning in a (post-) COVID-19 classroom.
MicroRNAs are endogenous small non‐coding RNAs that regulate gene expression and cancer development. A rare population of hepatocellular cancer stem cells (HSCs) holds the extensive proliferative and ...self‐renewal potential necessary to form a liver tumour. We postulated that specific transcriptional factors might regulate the expression of microRNAs and subsequently modulate the expression of gene products involved in phenotypic characteristics of HSCs. We evaluated the expression of microRNA in human HSCs by microarray profiling, and defined the target genes and functional effects of two groups of microRNA regulated by IL‐6 and transcriptional factor Twist. A subset of highly chemoresistant and invasive HSCs was screened with aberrant expressions of cytokine IL‐6 and Twist. We demonstrated that conserved let‐7 and miR‐181 family members were up‐regulated in HSCs by global microarray‐based microRNA profiling followed by validation with real‐time polymerase chain reaction. Importantly, inhibition of let‐7 increases the chemosensitivity of HSCs to sorafenib and doxorubicin whereas silencing of miR‐181 led to a reduction in HSCs motility and invasion. Knocking down IL‐6 and Twist in HSCs significantly reduced let‐7 and miR‐181 expression and subsequently inhibited chemoresistance and cell invasion. We showed that let‐7 directly targets SOCS‐1 and caspase‐3, whereas miR‐181 directly targets RASSF1A, TIMP3 as well as nemo‐like kinase (NLK). In conclusion, alterations of IL‐6‐ and Twist‐regulated microRNA expression in HSCs play a part in tumour spreading and responsiveness to chemotherapy. Our results define a novel regulatory mechanism of let‐7/miR‐181s suggesting that let‐7 and miR‐181 may be molecular targets for eradication of hepatocellular malignancies.
Background: Cardiology is but one of the many clinical foci available to certified Advanced Practice Registered Nurses (APRNs). In fact, more acute care APRNs choose cardiology as their focus than ...any other. With such strong interest in cardiac advanced practice nursing, it is imperative to assess the adequacy of preparation for those who wish to follow this career path. Known barriers exist in the educational and clinical preparation of this APRN population, however, there is little research detailing the specifics of those barriers.
Purpose: This study describes the needs of APRNs who plan to specialize in cardiology.
Method and Sampling: A qualitative design was used to describe the motivation of APRNs specializing in cardiology, tools they currently utilize to achieve their specialization, and their needs based on the current approach. I recruited participants, APRNs specializing in cardiology, through meetings at a local cardiology practice. Seven APRNs specializing in cardiology with experience ranging from 10 months to 15 years, and currently working in a cardiac setting, participated in the study. Structured interviews were conducted to describe the needs of APRNs who plan to specialize in cardiology. The interviews were audiotaped and analyzed to reveal commonalities.
Findings: After analyzing the audio recordings three major commonalities emerged: APRNs specializing in cardiology must overcome limited educational opportunities, APRNs specializing in cardiology require a higher level of skill than their formal training and licensing requirements provide, and the need to validate APRNs specializing in cardiology knowledge. Additional commonalities included availability and the type of degree programs, and a lack of cardiac focus in educational preparation.
Conclusion: The findings showed the needs of APRNs who plan to specialize in cardiology are rooted in their educational preparation. There is a vast amount of variability among degree programs and a severe lack of cardiac focus in their educational preparation. In order to achieve competency, 100% of study participants secured a mentorship with an expert cardiac clinician for a minimum of one year post-graduation and without assistance from their educational programs. Additionally, APRNs specializing in cardiology believe a national certification or examination requirement would be beneficial to their practice.
Background: Cardiology is but one of the many clinical foci available to certified Advanced Practice Registered Nurses (APRNs). In fact, more acute care APRNs choose cardiology as their focus than ...any other. With such strong interest in cardiac advanced practice nursing, it is imperative to assess the adequacy of preparation for those who wish to follow this career path. Known barriers exist in the educational and clinical preparation of this APRN population, however, there is little research detailing the specifics of those barriers. Purpose: This study describes the needs of APRNs who plan to specialize in cardiology. Method and Sampling: A qualitative design was used to describe the motivation of APRNs specializing in cardiology, tools they currently utilize to achieve their specialization, and their needs based on the current approach. I recruited participants, APRNs specializing in cardiology, through meetings at a local cardiology practice. Seven APRNs specializing in cardiology with experience ranging from 10 months to 15 years, and currently working in a cardiac setting, participated in the study. Structured interviews were conducted to describe the needs of APRNs who plan to specialize in cardiology. The interviews were audiotaped and analyzed to reveal commonalities. Findings: After analyzing the audio recordings three major commonalities emerged: APRNs specializing in cardiology must overcome limited educational opportunities, APRNs specializing in cardiology require a higher level of skill than their formal training and licensing requirements provide, and the need to validate APRNs specializing in cardiology knowledge. Additional commonalities included availability and the type of degree programs, and a lack of cardiac focus in educational preparation. Conclusion: The findings showed the needs of APRNs who plan to specialize in cardiology are rooted in their educational preparation. There is a vast amount of variability among degree programs and a severe lack of cardiac focus in their educational preparation. In order to achieve competency, 100% of study participants secured a mentorship with an expert cardiac clinician for a minimum of one year post-graduation and without assistance from their educational programs. Additionally, APRNs specializing in cardiology believe a national certification or examination requirement would be beneficial to their practice.
Health disparities in physical, psychological, and social well-being are known to exist among underserved and marginalized populations, and although it is widely accepted that public parks and ...greenspaces can provide these physical, mental and social benefits, underserved and minority communities are more likely to have an unequitable distribution of quality parks. Quality and maintenance of parks are important because neglect of existing parks can cause parks to be dangerous and unwelcoming spaces that diminish the value and benefits that these greenspaces can provide for residents. Underserved communities cannot typically afford landscape architecture services and historically, residents of these communities have been left out of the decision-making process when funding for parks have been distributed. One way that these distributional and procedural environmental injustices can be solved is through the work of non-profit community development organizations that utilize community engagement tools. Using a participatory design approach, this thesis explores how to redesign Duane Avenue Park, a neglected park located in south Baltimore, Maryland. The park design will be used by a local non-profit, the Greater Baybrook Alliance, to write proposals for grant funding for the future implementation of the Park. By researching literature related to this topic, performing site inventory and analysis, and conducting thorough stakeholder and community engagement through surveys, in-person events, and one-on-one interactions, I created a proposed site plan that addressed the following design goals:Goal 1: Improve Perception of Safety & Discourage Negative Uses Goal 2: Design an Adventure Park that Encourages Play and Connections with NatureGoal 3: Create Spaces for Gathering and other Activity GeneratorsGoal 4: Incorporate Public Art While this is not meant to provide evidence that one park can resolve all the issues a community faces, it can show that parks can be part of a larger community strategy that can help to address some issues such as health disparities, safety, and environmental justice.
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