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Objective: This study aimed to determine the relationship between spiritual, religious, and existential well-being and self-efficacy for appropriate medication use in African American women with hypertension. Methods: In this study, we conducted cross-sectional correlations using linear regression analysis. An African American sample of women from across the United States with hypertension was chosen through a purposive sampling technique. An online survey was used. Results: There were 186 African American women with hypertension who took part in the study, with an average age of 57.15 (SD = 12.79) years. The study found significant correlations between spiritual (p = .022), religious (p = .033), and existential (p = .021) well-being and self-efficacy for appropriate medication use in African American women with hypertension. The study concluded that no women reported high spiritual, religious, or existential well-being, only moderate. Nor were they very confident that they would take their medications under changing or challenging circumstances. Conclusion: African American women are the most religious aggregate in the United States, and there is evidence that spiritual, religious, and existential well-being affects their self-efficacy for appropriate medication use. Clinicians and researchers must collaborate to enhance medication adherence through continuous education, assessment, and reinforcement while also attuning their practice to spiritual, religious, and existential well-being effects on self-efficacy for appropriate medication use in African American women.
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The differential diagnosis for abdominal or pelvic pain in women of child-bearing age that present to the emergency department is broad. A rare cause of abdominal and pelvic pain is hematometra, or a collection of blood products within the uterus. While blood is normally expelled through menses, this process is disrupted in some patients due to congenital or acquired abnormalities. This can lead to progressive uterine distension and pain, which may ultimately require medical or surgical intervention. Hematometra is rare, but is a serious condition that can be diagnosed easily at bedside using point of care ultrasound.
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BACKGROUND: Pulmonary hypertension (PH) in heart failure with preserved ejection fraction (HFpEF) is a common and highly morbid syndrome, but mechanisms driving PH-HFpEF are poorly understood. We sought to determine whether a well-accepted murine model of HFpEF also displays features of PH, and we sought to identify pathways that might drive early remodeling of the pulmonary vasculature in HFpEF. METHODS: Eight-week-old male and female C57BL/6J mice received either Nγ-nitro-L-arginine methyl ester and high-fat diet or control water and diet for 2, 5, and 12 weeks. The db/db mice were studied as a second model of HFpEF. Early pathways regulating PH were identified by bulk and single-cell RNA sequencing. Findings were confirmed by immunostain in lungs of mice or lung slides from clinically performed autopsies of patients with PH-HFpEF. ELISA was used to verify IL-1ß (interleukin-1 beta) in mouse lung, mouse plasma, and also human plasma from patients with PH-HFpEF obtained at the time of right heart catheterization. Clodronate liposomes and an anti-IL-1ß antibody were utilized to deplete macrophages and IL-1ß, respectively, to assess their impact on pulmonary vascular remodeling in HFpEF in mouse models. RESULTS: Nγ-nitro-L-arginine methyl ester/high-fat diet-treated mice developed PH, small vessel muscularization, and right heart dysfunction. Inflammation-related gene ontologies were overrepresented in bulk RNA sequencing analysis of whole lungs, with an increase in CD68+ cells in both murine and human PH-HFpEF lungs. Cytokine profiling showed an increase in IL-1ß in mouse and human plasma. Finally, clodronate liposome treatment in mice prevented PH in Nγ-nitro-L-arginine methyl ester/high-fat diet-treated mice, and IL-1ß depletion also attenuated PH in Nγ-nitro-L-arginine methyl ester/high-fat diet-treated mice. CONCLUSIONS: We report a novel model for the study of PH and right heart remodeling in HFpEF, and we identify myeloid cell-derived IL-1ß as an important contributor to PH in HFpEF.
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Insuficiencia Cardíaca , Hipertensión Pulmonar , Animales , Femenino , Humanos , Masculino , Ratones , Ácido Clodrónico , Insuficiencia Cardíaca/metabolismo , Hipertensión Pulmonar/etiología , Interleucina-1beta , Ratones Endogámicos C57BL , Células Mieloides/metabolismo , Volumen Sistólico/fisiologíaRESUMEN
OBJECTIVES: A pilot study was performed to develop and test an observed structured clinical exam (OSCE) for clinical ultrasound in second-year medical students. The goal was to assess a longitudinal clinical ultrasound curriculum for medical students and to help determine readiness to perform ultrasound during clinical clerkships. METHODS: The OSCE contained 40 tasks over 30 min in a one-to-one examiner to examinee environment using standardized patients covering cardiac, pulmonary, and inferior vena cava (IVC) ultrasound exams along with 6 critical diagnoses. Examinees were assessed using a binary checklist approach. A two-way ANOVA analysis was performed to determine if there were differences between the day and session the OSCE was administered. Results are presented as mean ± standard deviation. RESULTS: One hundred fifty-two students were tested with an overall mean score of 64.9 ± 17.6%. Scores between the cardiac, IVC, and lung sections varied-67.8% ± 18.8%, 62.4% ± 26.2%, and 57.1% ± 20.6%, respectively. One hundred twenty-six (82.9%) answered at least one critical diagnosis incorrectly. Students in the late session performed better than the early session (1: 60% vs 2: 69%, p = .001). CONCLUSIONS: Students performed better in later sessions. Additionally, the number of questions left blank at the end of the exam suggests that the length of the OSCE should be evaluated. Incorporating critical diagnoses was challenging for examinees. The proposed OSCE is a valuable assessment tool that could be adapted to assess student's readiness to use clinical ultrasound prior to clerkships.
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BACKGROUND: Children with complex health needs (CCHN) have intersecting medical, behavioral health, and social needs. Unfortunately, fragmentation across health and social services sectors often results in uncoordinated care for CCHN and their families. OBJECTIVE: The purpose of this article is to describe the creation of a statewide cross-sector partnership, the Children's Complex Care Coalition of North Carolina, to identify and act on opportunities for system-level improvements in the care of CCHN. METHODS: We applied a virtual community engagement approach to form an advisory committee of cross-sector collaborators; systematically identify priorities most important and urgent to collaborators for improving systems of care; and host a series of virtual convenings involving more than 90 attendees from across the state to operationalize collaborator-identified priorities into actionable next steps. LESSONS LEARNED: Key facilitators of success for the Children's Complex Care Coalition of North Carolina partnership were investing time in building trusting relationships, particularly with families of CCHN, and aligning goals and priorities with existing local and regional efforts. Challenges included incorporating traditionally under-represented perspectives, right-sizing virtual convening attendance and number of topics covered, and navigating technological difficulties in a virtual environment. CONCLUSIONS: Health systems can catalyze the formation of cross-sector coalitions and community partnerships to advance complex care. Virtual convenings with interactive activities and participatory structures can be an efficient medium to connect coalition members and elicit actionable recommendations for system-level improvements that address the needs of community members.
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Salud Infantil , Investigación Participativa Basada en la Comunidad , Niño , Humanos , North CarolinaRESUMEN
Background: Pulmonary hypertension (PH) in heart failure with preserved ejection fraction (HFpEF) is a common and highly morbid syndrome, but mechanisms driving PH-HFpEF are not well understood. We sought to determine whether a well-accepted murine model of HFpEF also displays features of PH in HFpEF, and we sought to identify pathways that might drive early remodeling of the pulmonary vasculature in HFpEF. Methods: Eight week old male and female C57/BL6J mice were given either L-NAME and high fat diet (HFD) or control water/diet for 2,5, and 12 weeks. Bulk RNA sequencing and single cell RNA sequencing was performed to identify early and cell-specific pathways that might regulate pulmonary vascular remodeling in PH-HFpEF. Finally, clodronate liposome and IL1ß antibody treatments were utilized to deplete macrophages or IL1ß, respectively, to assess their impact on pulmonary vascular remodeling in HFpEF. Results: Mice given L-NAME/HFD developed PH, small vessel muscularization, and right heart dysfunction after 2 weeks of treatment. Inflammation-related gene ontologies were over-represented in bulk RNA sequencing analysis of whole lungs, with an increase in CD68+ cells in both murine and human PH-HFpEF lungs. Cytokine profiling of mouse lung and plasma showed an increase in IL1ß, which was confirmed in plasma from patients with HFpEF. Single cell sequencing of mouse lungs also showed an increase in M1-like, pro-inflammatory populations of Ccr2+ monocytes and macrophages, and transcript expression of IL1ß was primarily restricted to myeloid-type cells. Finally, clodronate liposome treatment prevented the development of PH in L-NAME/HFD treated mice, and IL1ß antibody treatment also attenuated PH in L-NAME/HFD treated mice. Conclusions: Our study demonstrated that a well-accepted model of HFpEF recapitulates features of pulmonary vascular remodeling commonly seen in patients with HFpEF, and we identified myeloid cell derived IL1ß as an important contributor to PH in HFpEF.
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Pressure overload of the heart is characterized by concentric hypertrophy and interstitial fibrosis. Cardiac fibroblasts (CFs) in the ventricular wall become activated during injury and synthesize and compact the extracellular matrix, which causes interstitial fibrosis and stiffening of the ventricular heart walls. Talin1 (Tln1) and Talin2 (Tln2) are mechanosensitive proteins that participate in focal adhesion transmission of signals from the extracellular environment to the actin cytoskeleton of CFs. The aim of the present study was to determine whether the removal of Tln1 and Tln2 from CFs would reduce interstitial fibrosis and cardiac hypertrophy. Twelve-week-old male and female Tln2-null (Tln2-/-) and Tln2-null, CF-specific Tln1 knockout (Tln2-/-;Tln1CF-/-) mice were given angiotensin-II (ANG II) (1.5 mg/kg/day) or saline through osmotic pumps for 8 wk. Cardiomyocyte area and measures of heart thickness were increased in the male ANG II-infused Tln2-/-;Tln1CF-/- mice, whereas there was no increase in interstitial fibrosis. Systolic blood pressure was increased in the female Tln2-/-;Tln1CF-/- mice after ANG II infusion compared with the Tln2-/- mice. However, there was no increase in cardiac hypertrophy in the Tln2-/-;Tln1CF-/- mice, which was seen in the Tln2-/- mice. Collectively, these data indicate that in male mice, the absence of Tln1 and Tln2 in CFs leads to cardiomyocyte hypertrophy in response to ANG II, whereas it results in a hypertrophy-resistant phenotype in female mice. These findings have important implications for the role of mechanosensitive proteins in CFs and their impact on cardiomyocyte function in the pathogenesis of hypertension and cardiac hypertrophy.NEW & NOTEWORTHY The role of talins has been previously studied in cardiomyocytes; however, these mechanotransductive proteins that are members of the focal adhesion complex have not been examined in cardiac fibroblasts previously. We hypothesized that loss of talins in cardiac fibroblasts would reduce interstitial fibrosis in the heart with a pressure overload model. However, we found that although loss of talins did not alter fibrosis, it did result in cardiomyocyte and ventricular hypertrophy.
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Miocitos Cardíacos , Talina , Angiotensina II/farmacología , Animales , Cardiomegalia/metabolismo , Femenino , Fibroblastos/metabolismo , Fibrosis , Masculino , Ratones , Ratones Noqueados , Miocardio/metabolismo , Miocitos Cardíacos/metabolismo , Talina/genética , Talina/metabolismoRESUMEN
Loss of function KCNK3 mutation is one of the gene variants driving hereditary pulmonary arterial hypertension (PAH). KCNK3 is expressed in several cell and tissue types on both membrane and endoplasmic reticulum and potentially plays a role in multiple pathological process associated with PAH. However, the role of various stressors driving the susceptibility of KCNK3 mutation to PAH is unknown. Hence, we exposed kcnk3fl/fl animals to hypoxia, metabolic diet and low dose lipopolysaccharide (LPS) and performed molecular characterization of their tissue. We also used tissue samples from KCNK3 patients (skin fibroblast derived inducible pluripotent stem cells, blood, lungs, peripheral blood mononuclear cells) and performed microarray, immunohistochemistry (IHC) and mass cytometry time of flight (CyTOF) experiments. Although a hypoxic insult did not alter vascular tone in kcnk3fl/fl mice, RNASeq study of these lungs implied that inflammatory and metabolic factors were altered, and the follow-up diet study demonstrated a dysregulation of bone marrow cells in kcnk3fl/fl mice. Finally, a low dose LPS study clearly showed that inflammation could be a possible second hit driving PAH in kcnk3fl/fl mice. Multiplex, IHC and CyTOF immunophenotyping studies on human samples confirmed the mouse data and strongly indicated that cell mediated, and innate immune responses may drive PAH susceptibility in these patients. In conclusion, loss of function KCNK3 mutation alters various physiological processes from vascular tone to metabolic diet through inflammation. Our data suggests that altered circulating immune cells may drive PAH susceptibility in patients with KCNK3 mutation.
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Inmunomodulación/genética , Mutación , Proteínas del Tejido Nervioso/genética , Canales de Potasio de Dominio Poro en Tándem/genética , Hipertensión Arterial Pulmonar/genética , Hipertensión Arterial Pulmonar/inmunología , Animales , Biomarcadores , Estudios de Casos y Controles , Citocinas/metabolismo , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Perfilación de la Expresión Génica , Predisposición Genética a la Enfermedad , Humanos , Hipoxia/genética , Hipoxia/metabolismo , Linfocitos/inmunología , Linfocitos/metabolismo , Ratones , Ratones Noqueados , Modelos Biológicos , Monocitos/inmunología , Monocitos/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Canales de Potasio de Dominio Poro en Tándem/metabolismo , Hipertensión Arterial Pulmonar/complicaciones , Hipertensión Arterial Pulmonar/fisiopatología , TranscriptomaRESUMEN
Background: Complications of fibroids in pregnancy are well known, including postpartum hemorrhage, labor dystocia, and cesarean delivery. Outside of pregnancy and labor, the rare occurrence of spontaneous fibroid rupture has been documented. Case: The current case report involves a woman who presented with acute abdominal pain in the third trimester of pregnancy and was found to have spontaneous rupture of a fibroid before the onset of labor. Her initial presentation, diagnosis through use of point-of-care ultrasound, acute surgical management, and postoperative course are described. Conclusion: When assessing acute abdominal pain in a pregnant patient, fibroid rupture should be considered despite the absence of prior uterine surgery. Bedside point-of-care ultrasonography is a useful tool for assessment of abdominal pain in the third trimester of pregnancy.
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Background: In 2012, mutations in Cav1 were found to be the driving mutation in several cases of heritable pulmonary arterial hypertension (PAH). These mutations replaced the last 21 amino acids of Cav1 with a novel 22-amino-acid sequence. Because previously only Cav1 knockouts had been studied in the context of PAH, examining the in vivo effects of this novel mutation holds promise for new understanding of the role of Cav1 in disease etiology. Methods: The new 22 amino acids created by the human mutation were knocked into the native mouse Cav1 locus. The mice underwent hemodynamic, energy balance, and inflammatory measurements, both at baseline and after being stressed with either a metabolic or an inflammatory challenge [low-dose lipopolysaccharide (LPS)]. To metabolically challenge the mice, they were injected with streptozotocin (STZ) and fed a high-fat diet for 12 weeks. Results: Very little mutant protein was found in vivo (roughly 2% of wild-type by mass spectrometry), probably because of degradation after failure to traffic from the endoplasmic reticulum. The homozygous mutants developed a mild, low-penetrance PAH similar to that described previously in knockouts, and neither baseline nor metabolic nor inflammatory stress resulted in pressures above normal in heterozygous animals. The homozygous mutants had increased lean mass and worsened oral glucose tolerance, as previously described in knockouts. Novel findings include the preservation of Cav2 and accessory proteins in the liver and the kidney, while they are lost with homozygous Cav1 mutation in the lungs. We also found that the homozygous mutants had a significantly lower tolerance to voluntary spontaneous exercise than the wild-type mice, with the heterozygous mice at an intermediate level. The mutants also had higher circulating monocytes, with both heterozygous and homozygous animals having higher pulmonary MCP1 and MCP5 proteins. The heterozygous animals also lost weight at an LPS challenge level at which the wild-type mice continued to gain weight. Conclusions: The Cav1 mutation identified in human patients in 2012 is molecularly similar to a knockout of Cav1. It results in not only metabolic deficiencies and mild pulmonary hypertension, as expected, but also an inflammatory phenotype and reduced spontaneous exercise.
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Dolor Abdominal/diagnóstico por imagen , Intestino Delgado/diagnóstico por imagen , Isquemia/diagnóstico por imagen , Vena Porta/diagnóstico por imagen , Trombosis de la Vena/diagnóstico por imagen , Adulto , Anticoagulantes/uso terapéutico , Procedimientos Quirúrgicos del Sistema Digestivo , Servicio de Urgencia en Hospital , Femenino , Heparina/uso terapéutico , Humanos , Intestino Delgado/patología , Intestino Delgado/cirugía , Isquemia/patología , Isquemia/cirugía , Sistemas de Atención de Punto , Resultado del Tratamiento , Ultrasonografía , Trombosis de la Vena/patología , Trombosis de la Vena/cirugíaRESUMEN
Inflammation is a major cause of morbidity and mortality in Western societies. Despite use of multiple drugs, both chronic and acute inflammation still represent major health burdens. Inflammation produces highly reactive dicarbonyl lipid peroxidation products such as isolevuglandins which covalently modify and cross-link proteins via lysine residues. Mitochondrial dysfunction has been associated with inflammation; however, its molecular mechanisms and pathophysiological role are still obscure. We hypothesized that inflammation-induced isolevuglandins contribute to mitochondrial dysfunction and mortality. To test this hypothesis, we have (a) investigated the mitochondrial dysfunction in response to synthetic 15-E2-isolevuglandin (IsoLG) and its adducts; (b) developed a new mitochondria-targeted scavenger of isolevuglandins by conjugating 2-hydroxybenzylamine to the lipophilic cation triphenylphosphonium, (4-(4-aminomethyl)-3-hydroxyphenoxy)butyl)-triphenylphosphonium (mito2HOBA); (c) tested if mito2HOBA protects from mitochondrial dysfunction and mortality using a lipopolysaccharide model of inflammation. Acute exposure to either IsoLG or IsoLG adducts with lysine, ethanolamine or phosphatidylethanolamine inhibits mitochondrial respiration and attenuates Complex I activity. Complex II function was much more resistant to IsoLG. We confirmed that mito2HOBA markedly accumulates in isolated mitochondria and it is highly reactive with IsoLGs. To test the role of mitochondrial IsoLGs, we studied the therapeutic potential of mito2HOBA in lipopolysaccharide mouse model of sepsis. Mito2HOBA supplementation in drinking water (0.1â¯g/L) to lipopolysaccharide treated mice increased survival by 3-fold, improved complex I-mediated respiration, and histopathological analyses supported mito2HOBA-mediated protection of renal cortex from cell injury. These data support the role of mitochondrial IsoLG in mitochondrial dysfunction and inflammation. We conclude that reducing mitochondrial IsoLGs may be a promising therapeutic target in inflammation and conditions associated with mitochondrial oxidative stress and dysfunction.
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Inflamación/metabolismo , Lípidos/farmacología , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Animales , Respiración de la Célula/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Complejo I de Transporte de Electrón/metabolismo , Complejo II de Transporte de Electrones/metabolismo , Activación Enzimática/efectos de los fármacos , Inflamación/etiología , Riñón/metabolismo , Peroxidación de Lípido , Lípidos/química , Lipopolisacáridos/efectos adversos , Lipopolisacáridos/inmunología , Ratones , Estrés Oxidativo , Sepsis/etiología , Sepsis/metabolismo , Sepsis/mortalidadRESUMEN
RATIONALE: Pulmonary arterial hypertension is a deadly disease of the pulmonary vasculature for which no disease-modifying therapies exist. Small-vessel stiffening and remodeling are fundamental pathological features of pulmonary arterial hypertension that occur early and drive further endovascular cell dysfunction. Bone marrow (BM)-derived proangiogenic cells (PACs), a specialized heterogeneous subpopulation of myeloid lineage cells, are thought to play an important role in pathogenesis. OBJECTIVE: To determine whether BM-derived PACs directly contributed to experimental pulmonary hypertension (PH) by promoting small-vessel stiffening through 5-HT2B (serotonin 2B receptor)-mediated signaling. METHODS AND RESULTS: We performed BM transplants using transgenic donor animals expressing diphtheria toxin secondary to activation of an endothelial-specific tamoxifen-inducible Cre and induced experimental PH using hypoxia with SU5416 to enhance endovascular injury and ablated BM-derived PACs, after which we measured right ventricular systolic pressures in a closed-chest procedure. BM-derived PAC lineage tracing was accomplished by transplanting BM from transgenic donor animals with fluorescently labeled hematopoietic cells and treating mice with a 5-HT2B antagonist. BM-derived PAC ablation both prevented and reversed experimental PH with SU5416-enhanced endovascular injury, reducing the number of muscularized pulmonary arterioles and normalizing arteriole stiffness as measured by atomic force microscopy. Similarly, treatment with a pharmacological antagonist of 5-HT2B also prevented experimental PH, reducing the number and stiffness of muscularized pulmonary arterioles. PACs accelerated pulmonary microvascular endothelial cell injury response in vitro, and the presence of BM-derived PACs significantly correlated with stiffer pulmonary arterioles in pulmonary arterial hypertension patients and mice with experimental PH. RNA sequencing of BM-derived PACs showed that 5-HT2B antagonism significantly altered biologic pathways regulating cell proliferation, locomotion and migration, and cytokine production and response to cytokine stimulus. CONCLUSIONS: Together, our findings illustrate that BM-derived PACs directly contribute to experimental PH with SU5416-enhanced endovascular injury by mediating small-vessel stiffening and remodeling in a 5-HT2B signaling-dependent manner.
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Hipertensión Pulmonar/patología , Células Progenitoras Mieloides/metabolismo , Receptor de Serotonina 5-HT2B/metabolismo , Rigidez Vascular , Inhibidores de la Angiogénesis/toxicidad , Animales , Arteriolas/patología , Linaje de la Célula , Células Cultivadas , Hipertensión Pulmonar/sangre , Hipertensión Pulmonar/etiología , Indoles/toxicidad , Pulmón/irrigación sanguínea , Ratones , Ratones Endogámicos C57BL , Células Progenitoras Mieloides/citología , Células Progenitoras Mieloides/trasplante , Pirroles/toxicidadRESUMEN
Background: Pulmonary hypertension (PH) is a progressive cardiovascular disease, characterized by endothelial and smooth muscle dysfunction and vascular remodeling, followed by right heart failure. Group III PH develops secondarily to chronic lung disease such as idiopathic pulmonary fibrosis (IPF), and both hastens and predicts mortality despite of all known pharmacological interventions. Thus, there is urgent need for development of newer treatment strategies. Objective: Angiotensin converting enzyme 2 (ACE2), a member of the renin angiotensin family, is therapeutically beneficial in animal models of pulmonary vascular diseases and is currently in human clinical trials for primary PH. Although previous studies suggest that administration of ACE2 prevents PH secondary to bleomycin-induced murine IPF, it is unknown whether ACE2 can reverse or treat existing disease. Therefore, in the present study, we tested the efficacy of ACE2 in arresting the progression of group 3 PH. Methods: To establish pulmonary fibrosis, we administered 0.018 U/g bleomycin 2x/week for 4 weeks in adult FVB/N mice, and sacrificed 5 weeks following the first injection. ACE2 or vehicle was administered via osmotic pump for the final 2 weeks, beginning 3 weeks after bleomycin. Echocardiography and hemodynamic assessment was performed prior to sacrifice and tissue collection. Results: Administration of bleomycin significantly increased lung collagen expression, pulmonary vascular remodeling, and pulmonary arterial pressure, and led to mild right ventricular hypertrophy. Acute treatment with ACE2 significantly attenuated vascular remodeling and increased pulmonary SOD2 expression without measurable effects on pulmonary fibrosis. This was associated with nonsignificant positive effects on pulmonary arterial pressure and cardiac function. Conclusion: Collectively, our findings enumerate that ACE2 treatment improved pulmonary vascular muscularization following bleomycin exposure, concomitant with increased SOD2 expression. Although it may not alter the pulmonary disease course of IPF, ACE2 could be an effective therapeutic strategy for the treatment of group 3 PH.
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Haploinsufficiency of the melanocortin-4 receptor, the most common monogenetic obesity syndrome in humans, is associated with a reduction in autonomic tone, bradycardia, and incidence of obesity-associated hypertension. Thus, it has been assumed that melanocortin obesity syndrome may be protective with respect to obesity-associated cardiovascular disease. We show here that absence of the melanocortin-4 receptor (MC4R) in mice causes dilated cardiomyopathy, characterized by reduced contractility and increased left ventricular diameter. This cardiomyopathy is independent of obesity as weight matched diet induced obese mice do not display systolic dysfunction. Mc4r cardiomyopathy is characterized by ultrastructural changes in mitochondrial morphology and cardiomyocyte disorganization. Remarkably, testing of myocardial tissue from Mc4r-/- mice exhibited increased ADP stimulated respiratory capacity. However, this increase in respiration correlates with increased reactive oxygen species production - a canonical mediator of tissue damage. Together this study identifies MC4R deletion as a novel and potentially clinically important cause of heart failure.
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Cardiomiopatía Dilatada/genética , Cardiomiopatía Dilatada/patología , Receptor de Melanocortina Tipo 4/deficiencia , Adenosina Difosfato/metabolismo , Animales , Respiración de la Célula/efectos de los fármacos , Ratones Endogámicos C57BL , Ratones Noqueados , Mitocondrias/ultraestructura , Miocardio/patología , Miocitos Cardíacos/patología , Especies Reactivas de Oxígeno/metabolismo , Especies Reactivas de Oxígeno/toxicidadRESUMEN
Pulmonary hypertension (PH) complicating chronic parenchymal lung disease, such as idiopathic pulmonary fibrosis, results in significant morbidity and mortality. Since the hypoxia-inducible factor (HIF) signaling pathway is important for development of pulmonary hypertension in chronic hypoxia, we investigated whether HIF signaling in vascular endothelium regulates development of PH related to pulmonary fibrosis. We generated a transgenic model in which HIF is deleted within vascular endothelial cells and then exposed these mice to chronic intraperitoneal bleomycin to induce PH associated with lung fibrosis. Although no differences in the degree of fibrotic remodeling were observed, we found that endothelial HIF-deficient mice were protected against development of PH, including right ventricle and pulmonary vessel remodeling. Similarly, endothelial HIF-deficient mice were protected from PH after a 4-wk exposure to normobaric hypoxia. In vitro studies of pulmonary vascular endothelial cells isolated from the HIF-targeted mice and controls revealed that endothelial HIF signaling increases endothelial cell expression of connective tissue growth factor, enhances vascular permeability, and promotes pulmonary artery smooth muscle cell proliferation and wound healing ability, all of which have the potential to impact the development of PH in vivo. Taken together, these studies demonstrate that vascular endothelial cell HIF signaling is necessary for development of hypoxia and pulmonary fibrosis associated PH. As such, HIF and HIF-regulated targets represent a therapeutic target in these conditions.
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Células Endoteliales/metabolismo , Hipertensión Pulmonar/metabolismo , Factor 1 Inducible por Hipoxia/metabolismo , Arteria Pulmonar/metabolismo , Animales , Proliferación Celular/fisiología , Células Cultivadas , Endotelio Vascular/metabolismo , Fibrosis/etiología , Hipertensión Pulmonar/complicaciones , Hipoxia/metabolismo , Ratones Transgénicos , Músculo Liso Vascular/metabolismo , Remodelación Vascular/fisiologíaRESUMEN
Pulmonary fibrosis is often complicated by pulmonary hypertension (PH), and previous studies have shown a potential link between bone morphogenetic protein receptor II (BMPR2) and PH secondary to pulmonary fibrosis. We exposed transgenic mice expressing mutant BMPR2 and control mice to repetitive intraperitoneal injections of bleomycin for 4 weeks. The duration of transgene activation was too short for mutant BMPR2 mice to develop spontaneous PH. Mutant BMPR2 mice had increased right ventricular systolic pressure compared to control mice, without differences in pulmonary fibrosis. We found increased hypoxia-inducible factor (HIF)1-α stabilization in lungs of mutant-BMPR2-expressing mice compared to controls following bleomycin treatment. In addition, expression of the hypoxia response element protein connective tissue growth factor was increased in transgenic mice as well as in a human pulmonary microvascular endothelial cell line expressing mutant BMPR2. In mouse pulmonary vascular endothelial cells, mutant BMPR2 expression resulted in increased HIF1-α and reactive oxygen species production following exposure to hypoxia, both of which were attenuated with the antioxidant TEMPOL. These data suggest that expression of mutant BMPR2 worsens secondary PH through increased HIF activity in vascular endothelium. This pathway could be therapeutically targeted in patients with PH secondary to pulmonary fibrosis.
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Engineering educators have long discussed the need to teach professional responsibility and the social context of engineering without adding to overcrowded curricula. One difficulty we face is the lack of appropriate teaching materials that can fit into existing courses. The PRiME (Professional Responsibility Modules for Engineering) Project (http://www.engr.utexas.edu/ethics/primeModules.cfm) described in this paper was initiated at the University of Texas, Austin to provide web-based modules that could be integrated into any undergraduate engineering class. Using HPL (How People Learn) theory, PRiME developed and piloted four modules during the academic year 2004-2005. This article introduces the modules and the pilot, outlines the assessment process, analyzes the results, and describes how the modules are being revised in light of the initial assessment. In its first year of development and testing, PRiME made significant progress towards meeting its objectives. The PRiME Project can strengthen engineering education by providing faculty with an effective system for engaging students in learning about professional responsibility.