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1.
Sci Adv ; 10(19): eadh0798, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38718107

ABSTRACT

Mutations in the LMNA gene encoding lamins A/C cause an array of tissue-selective diseases, with the heart being the most commonly affected organ. Despite progress in understanding the perturbations emanating from LMNA mutations, an integrative understanding of the pathogenesis underlying cardiac dysfunction remains elusive. Using a novel conditional deletion model capable of translatome profiling, we observed that cardiomyocyte-specific Lmna deletion in adult mice led to rapid cardiomyopathy with pathological remodeling. Before cardiac dysfunction, Lmna-deleted cardiomyocytes displayed nuclear abnormalities, Golgi dilation/fragmentation, and CREB3-mediated stress activation. Translatome profiling identified MED25 activation, a transcriptional cofactor that regulates Golgi stress. Autophagy is disrupted in the hearts of these mice, which can be recapitulated by disrupting the Golgi. Systemic administration of modulators of autophagy or ER stress significantly delayed cardiac dysfunction and prolonged survival. These studies support a hypothesis wherein stress responses emanating from the perinuclear space contribute to the LMNA cardiomyopathy development.


Subject(s)
Cardiomyopathies , Lamin Type A , Myocytes, Cardiac , Nuclear Envelope , Animals , Lamin Type A/metabolism , Lamin Type A/genetics , Mice , Nuclear Envelope/metabolism , Cardiomyopathies/metabolism , Cardiomyopathies/etiology , Cardiomyopathies/pathology , Cardiomyopathies/genetics , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/pathology , Autophagy , Stress, Physiological , Disease Models, Animal , Endoplasmic Reticulum Stress , Golgi Apparatus/metabolism , Mice, Knockout
2.
Int J Mol Sci ; 24(7)2023 Mar 24.
Article in English | MEDLINE | ID: mdl-37047128

ABSTRACT

Mediator 25 (Med25) is a member of the mediator complex that relays signals from transcription factors to the RNA polymerase II machinery. Multiple transcription factors, particularly those involved in lipid metabolism, utilize the mediator complex, but how Med25 is involved in this context is unclear. We previously identified Med25 in a translatome screen of adult cardiomyocytes (CMs) in a novel cell type-specific model of LMNA cardiomyopathy. In this study, we show that Med25 upregulation is coincident with myocardial lipid accumulation. To ascertain the role of Med25 in lipid accumulation, we utilized iPSC-derived and neonatal CMs to recapitulate the in vivo phenotype by depleting lamins A and C (lamin A/C) in vitro. Although lamin A/C depletion elicits lipid accumulation, this effect appears to be mediated by divergent mechanisms dependent on the CM developmental state. To directly investigate Med25 in lipid accumulation, we induced adipogenesis in Med25-silenced 3T3-L1 preadipocytes and detected enhanced lipid accumulation. Assessment of pertinent mediators driving adipogenesis revealed that C/EBPα and PPARγ are super-induced by Med25 silencing. Our results indicate that Med25 limits adipogenic potential by suppressing the levels of master regulators that govern adipogenesis. Furthermore, we caution the use of early-developmental-stage cardiomyocytes to model adult-stage cells, particularly for dissecting metabolic perturbations emanating from LMNA mutations.


Subject(s)
Adipogenesis , Lamin Type A , Animals , Mice , 3T3-L1 Cells , Adipogenesis/genetics , Cell Differentiation , Lamin Type A/genetics , Lamin Type A/metabolism , Lipids/pharmacology , Mediator Complex/genetics , Mediator Complex/metabolism , PPAR gamma/metabolism , Transcription Factors/metabolism
3.
bioRxiv ; 2023 Jun 07.
Article in English | MEDLINE | ID: mdl-36824975

ABSTRACT

Mutations in the LMNA gene encoding nuclear lamins A/C cause a diverse array of tissue-selective diseases, with the heart being the most commonly affected organ. Despite progress in understanding the molecular perturbations emanating from LMNA mutations, an integrative understanding of the pathogenesis leading to cardiac dysfunction remains elusive. Using a novel cell-type specific Lmna deletion mouse model capable of translatome profiling, we found that cardiomyocyte-specific Lmna deletion in adult mice led to rapid cardiomyopathy with pathological remodeling. Prior to the onset of cardiac dysfunction, lamin A/C-depleted cardiomyocytes displayed nuclear envelope deterioration, golgi dilation/fragmentation, and CREB3-mediated golgi stress activation. Translatome profiling identified upregulation of Med25, a transcriptional co-factor that can selectively dampen UPR axes. Autophagy is disrupted in the hearts of these mice, which can be recapitulated by disrupting the golgi or inducing nuclear damage by increased matrix stiffness. Systemic administration of pharmacological modulators of autophagy or ER stress significantly improved the cardiac function. These studies support a hypothesis wherein stress responses emanating from the perinuclear space contribute to the development of LMNA cardiomyopathy. Teaser: Interplay of stress responses underlying the development of LMNA cardiomyopathy.

4.
Methods Mol Biol ; 2626: 399-444, 2023.
Article in English | MEDLINE | ID: mdl-36715918

ABSTRACT

Citizen science is a productive approach to include non-scientists in research efforts that impact particular issues or communities. In most cases, scientists at advanced career stages design high-quality, exciting projects that enable citizen contribution, a crowdsourcing process that drives discovery forward and engages communities. The challenges of having citizens design their own research with no or limited training and providing access to laboratory tools, reagents, and supplies have limited citizen science efforts. This leaves the incredible life experiences and immersion of citizens in communities that experience health disparities out of the research equation, thus hampering efforts to address community health needs with a full picture of the challenges that must be addressed. Here, we present a robust and reproducible approach that engages participants from Grade 5 through adult in research focused on defining how diet impacts disease signaling. We leverage the powerful genetics, cell biology, and biochemistry of Drosophila oogenesis to define how nutrients impact phenotypes associated with genetic mutants that are implicated in cancer and diabetes. Participants lead the project design and execution, flipping the top-down hierarchy of the prevailing scientific culture to co-create research projects and infuse the research with cultural and community relevance.


Subject(s)
Drosophila , Public Health , Animals , Research
5.
Proc Natl Acad Sci U S A ; 119(15): e2109448119, 2022 04 12.
Article in English | MEDLINE | ID: mdl-35394871

ABSTRACT

Genetic studies of hippocampal granule neuron development have been used to elucidate cellular functions of Pten and Fmr1. While mutations in each gene cause neurodevelopmental disorders such as autism and fragile X syndrome, how Pten and Fmr1 function alone or together during normal development is not known. Moreover, Pten mRNA is bound by the fragile X mental retardation protein (FMRP) RNA binding protein, but how this physical interaction impinges on phosphatase and tensin homolog protein (PTEN) expression is not known. To understand the interaction of PTEN and FMRP, we investigated the dentate gyrus granule neuron development in Pten and Fmr1 knockout (KO) mice. Interestingly, heterozygosity of Pten restored Fmr1 KO cellular phenotypes, including dendritic arborization, and spine density, while PTEN protein expression was significantly increased in Fmr1 KO animals. However, complete deletion of both Pten and Fmr1 resulted in a dramatic increase in dendritic length, spine density, and spine length. In addition, overexpression of PTEN in Fmr1 KO Pten heterozygous background reduced dendritic length, arborization, spine density, and spine length including pS6 levels. Our findings suggest that PTEN levels are negatively regulated by FMRP, and some Fmr1 KO phenotypes are caused by dysregulation of PTEN protein. These observations provide evidence for the genetic interaction of PTEN and FMRP and a possible mechanistic basis for the pathogenesis of Fmr1-related fragile X neurodevelopmental disorders.


Subject(s)
Fragile X Mental Retardation Protein , Fragile X Syndrome , PTEN Phosphohydrolase , Animals , Dentate Gyrus/cytology , Dentate Gyrus/growth & development , Disease Models, Animal , Fragile X Mental Retardation Protein/genetics , Fragile X Mental Retardation Protein/metabolism , Fragile X Syndrome/genetics , Fragile X Syndrome/metabolism , Heterozygote , Mice , Mice, Inbred C57BL , Mice, Knockout , Neurogenesis/genetics , Neurons/metabolism , Neurons/pathology , PTEN Phosphohydrolase/genetics , PTEN Phosphohydrolase/metabolism
6.
Nurse Educ ; 46(2): 101-105, 2021.
Article in English | MEDLINE | ID: mdl-32433379

ABSTRACT

BACKGROUND: Advanced health assessment is a required course in advanced practice RN (APRN) education, essential to providing the foundation for differential diagnosis (DD) skills and the ability to formulate a plan of care. PROBLEM: Feedback from clinical preceptors revealed that our doctor of nursing practice (DNP) students struggled to make a DD. APPROACH: This educational quality improvement project collected data from 7 cohorts of DNP students in either the Family Nurse Practitioner or Adult Gerontology Nurse Practitioner program to evaluate their readiness for clinical practicums and to inform necessary curriculum revisions. OUTCOMES: Data revealed that students' ability to identify 3 DDs correctly during the summative health assessment objective structured clinical examination was inconsistent. Qualitative data revealed students lacked understanding on how to use results from the physical assessment to formulate a DD. CONCLUSION: The findings of this project corroborate those from the literature that suggest we should teach APRN students DD skills explicitly.


Subject(s)
Advanced Practice Nursing , Curriculum , Education, Nursing, Graduate , Students, Nursing , Advanced Practice Nursing/education , Clinical Competence , Cohort Studies , Diagnosis, Differential , Education, Nursing, Graduate/methods , Humans , Nursing Education Research , Nursing Evaluation Research , Preceptorship , Students, Nursing/psychology
7.
J Am Assoc Nurse Pract ; 32(5): 400-407, 2020 May.
Article in English | MEDLINE | ID: mdl-31577668

ABSTRACT

Preceptors are essential to nurse practitioner (NP) students' transition from being a student to competent entry-level NP graduate. The literature is replete with data pertaining to the benefits of and barriers to preceptors engaging in the clinical education of NP students, and little has changed in the last two decades in this regard. Therefore, faculty solicited preceptor input to enhance curriculum revision and clinical training preparation. This qualitative inquiry project derived data from interviews with 13 preceptors in a variety of clinical settings. Interviews were audio-recorded, transcribed verbatim, and analyzed using a content analysis method. Recruiting, training, and retaining qualified, willing preceptors are of paramount importance to NP programs. This article describes preceptor expectations of NP students' knowledge, skills, and attitudes for optimal clinical rotation experiences. The results have important implications for innovative NP educational models, developing trust in NP education programs and promoting competency development of the NP student using entrustable professional activities.


Subject(s)
Education, Nursing, Graduate/standards , Mentors/psychology , Preceptorship/standards , Attitude of Health Personnel , Clinical Competence/standards , Clinical Competence/statistics & numerical data , Education, Nursing, Graduate/methods , Education, Nursing, Graduate/statistics & numerical data , Humans , Interviews as Topic/methods , Mentors/statistics & numerical data , Preceptorship/methods , Preceptorship/statistics & numerical data , Qualitative Research , Quality Improvement
8.
Malawi Med J ; 29(2): 118-123, 2017 06.
Article in English | MEDLINE | ID: mdl-28955418

ABSTRACT

BACKGROUND: The aim of this study was to understand the perceptions and experiences of health education and self-management practices on Malamulo Adventist Hospital type 2 diabetic patients. METHODS: In this qualitative study, key informant interviews (KIIs; n=4) and focus group discussions (3 FGDs; n=16) were conducted amongst type 2 diabetes patients who had been treated at Malamulo Adventist Hospital in southern Malawi at least once. Key informant interviews and focus group discussions were audio recorded, transcribed verbatim and translated for analysis. Grounded theory methods were used to identify line-by-line emerging codes and were categorized and examined in Atlas.ti. The data was analyzed for emergent themes and supported by critical quotes. RESULTS: Content analysis revealed participants had a positive regard for the diabetes education classes and had satisfactory health literacy. Participants expressed their ability to integrate diabetes education, such as exercise into their lifestyle. Due to financial constraints subjects experienced trouble maintaining their medication regimen, and had difficulty adopting healthier nutritional alternatives. Although patients expressed efficacy in controlling their blood sugar they subsequently expressed having limited knowledge when dealing with diabetes complications. CONCLUSIONS: Diabetes self-management is comprised of a complex set of processes. Patients with type 2 diabetes at Malamulo Adventist Hospital are deeply impacted by these processes which includes their understanding of the disease process, effects of medication, economic challenges to acquiring health care services and medications, and one's unique life experience. For all patients with type 2 diabetes to successfully manage their condition, support from their family, the medical community, and health policies must be readily available.


Subject(s)
Diabetes Mellitus, Type 2/therapy , Health Education , Health Knowledge, Attitudes, Practice , Patient Education as Topic , Self Care , Female , Focus Groups , Humans , Interviews as Topic , Malawi , Male , Middle Aged , Qualitative Research , Self-Management , Young Adult
9.
Adv Neonatal Care ; 13(5): 361-8, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24042144

ABSTRACT

PURPOSE: Although the American Academy of Pediatrics and the American Congress of Obstetricians and Gynecologists recommend obtaining temperature in newborn infants via the axilla, controversy still exists whether to obtain rectal or axillary temperatures. Of concern is the risk of perforating the rectum or colon during rectal temperature-taking. The purpose of this study was to explore the accuracy of electronic thermometer measuring temperature in the axilla compared with the rectum in full-term newborn infants. DESIGN: This was an agreement study involving a purposive sample of newborn infants who were greater than 37 weeks' gestation. The general care nursery was located in a large, urban Midwestern academic medical center, and data collection occurred between May 2010 and August 2010. METHODS: On admission to the general care nursery, both axillary and rectal temperatures were taken using the FasTemp device by Filac Electronic. Axillary temperatures were taken first, followed immediately by rectal temperature. Descriptive statistics, Pearson correlations, and scatter plots were computed. RESULTS: In 69 newborns, the mean difference between rectal and left axilla temperatures was 0.23°C. There was a significant correlation between rectal temperature and the body temperature for the left axilla (r = 0.786; P = .01). CONCLUSIONS: These preliminary data support the use of left axillary temperature measurement in the full-term newborn infant in the first few days of life to provide a safe and accurate alternative to rectal temperatures. CLINICAL RELEVANCE: Nurses caring for newborn infants now have evidence showing that temperature-taking in the left axilla is an alternative to using rectal temperatures, possibly minimizing discomfort and potential risk of perforation.


Subject(s)
Axilla/physiology , Body Temperature/physiology , Rectum/physiology , Female , Humans , Infant, Newborn , Male , Practice Guidelines as Topic , Regression Analysis , Reproducibility of Results , Thermometers
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