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1.
Arterioscler Thromb Vasc Biol ; 42(1): 35-48, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34758633

RESUMO

OBJECTIVE: Animal models of atherosclerosis are used extensively to interrogate molecular mechanisms in serial fashion. We tested whether a novel systems biology approach to integration of preclinical data identifies novel pathways and regulators in human disease. Approach and Results: Of 716 articles published in ATVB from 1995 to 2019 using the apolipoprotein E knockout mouse to study atherosclerosis, data were extracted from 360 unique studies in which a gene was experimentally perturbed to impact plaque size or composition and analyzed using Ingenuity Pathway Analysis software. TREM1 (triggering receptor expressed on myeloid cells) signaling and LXR/RXR (liver X receptor/retinoid X receptor) activation were identified as the top atherosclerosis-associated pathways in mice (both P<1.93×10-4, TREM1 implicated early and LXR/RXR in late atherogenesis). The top upstream regulatory network in mice (sc-58125, a COX2 inhibitor) linked 64.0% of the genes into a single network. The pathways and networks identified in mice were interrogated by testing for associations between the genetically predicted gene expression of each mouse pathway-identified human homolog with clinical atherosclerosis in a cohort of 88 660 human subjects. Homologous human pathways and networks were significantly enriched for gene-atherosclerosis associations (empirical P<0.01 for TREM1 and LXR/RXR pathways and COX2 network). This included 12(60.0%) TREM1 pathway genes, 15(53.6%) LXR/RXR pathway genes, and 67(49.3%) COX2 network genes. Mouse analyses predicted, and human study validated, the strong association of COX2 expression (PTGS2) with increased likelihood of atherosclerosis (odds ratio, 1.68 per SD of genetically predicted gene expression; P=1.07×10-6). CONCLUSIONS: PRESCIANT (Preclinical Science Integration and Translation) leverages published preclinical investigations to identify high-confidence pathways, networks, and regulators of human disease.


Assuntos
Apolipoproteínas E/genética , Aterosclerose/genética , Redes Reguladoras de Genes , Biologia de Sistemas , Adulto , Idoso , Animais , Apolipoproteínas E/deficiência , Aterosclerose/metabolismo , Aterosclerose/patologia , Modelos Animais de Doenças , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Camundongos Knockout para ApoE , Pessoa de Meia-Idade , Fenótipo , Placa Aterosclerótica , Medição de Risco , Fatores de Risco , Fatores Sexuais , Especificidade da Espécie
2.
Crit Care Med ; 50(10): 1461-1476, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36106970

RESUMO

OBJECTIVES: To assess recent advances in interfacility critical care transport. DATA SOURCES: PubMed English language publications plus chapters and professional organization publications. STUDY SELECTION: Manuscripts including practice manuals and standard (1990-2021) focused on interfacility transport of critically ill patients. DATA EXTRACTION: Review of society guidelines, legislative requirements, objective measures of outcomes, and transport practice standards occurred in work groups assessing definitions and foundations of interfacility transport, transport team composition, and transport specific considerations. Qualitative analysis was performed to characterize current science regarding interfacility transport. DATA SYNTHESIS: The Task Force conducted an integrative review of 496 manuscripts combined with 120 from the authors' collections including nonpeer reviewed publications. After title and abstract screening, 40 underwent full-text review, of which 21 remained for qualitative synthesis. CONCLUSIONS: Since 2004, there have been numerous advances in critical care interfacility transport. Clinical deterioration may be mitigated by appropriate patient selection, pretransport optimization, and transport by a well-resourced team and vehicle. There remains a dearth of high-quality controlled studies, but notable advances in monitoring, en route management, transport modality (air vs ground), as well as team composition and training serve as foundations for future inquiry. Guidance from professional organizations remains uncoupled from enforceable regulations, impeding standardization of transport program quality assessment and verification.


Assuntos
Deterioração Clínica , Estado Terminal , Cuidados Críticos , Estado Terminal/terapia , Humanos , Transporte de Pacientes
3.
Arterioscler Thromb Vasc Biol ; 41(11): 2740-2755, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34615372

RESUMO

Objective: MR (mineralocorticoid receptor) activation associates with increased risk of cardiovascular ischemia while MR inhibition reduces cardiovascular-related mortality and plaque inflammation in mouse atherosclerosis. MR in myeloid cells (My-MR) promotes inflammatory cell infiltration into injured tissues and atherosclerotic plaque inflammation by unclear mechanisms. Here, we examined the role of My-MR in leukocyte trafficking and the impact of sex. Approach and Results: We confirm in vivo that My-MR deletion (My-MR-KO) in ApoE-KO mice decreased plaque size. Flow cytometry revealed fewer plaque macrophages with My-MR-KO. By intravital microscopy, My-MR-KO significantly attenuated monocyte slow-rolling and adhesion to mesenteric vessels and decreased peritoneal infiltration of myeloid cells in response to inflammatory stimuli in male but not female mice. My-MR-KO mice had significantly less PSGL1 (P-selectin glycoprotein ligand 1) mRNA in peritoneal macrophages and surface PSGL1 protein on circulating monocytes in males. In vitro, MR activation with aldosterone significantly increased PSGL1 mRNA only in monocytes from MR-intact males. Similarly, aldosterone induced, and MR antagonist spironolactone inhibited, PSGL1 expression in human U937 monocytes. Mechanistically, aldosterone stimulated MR binding to a predicted MR response element in intron-1 of the PSGL1 gene by ChIP-qPCR. Reporter assays demonstrated that this PSGL1 MR response element is necessary and sufficient for aldosterone-activated, MR-dependent transcriptional activity. Conclusions: These data identify PSGL1 as a My-MR target gene that drives leukocyte trafficking to enhance atherosclerotic plaque inflammation. These novel and sexually dimorphic findings provide insight into increased ischemia risk with MR activation, cardiovascular protection in women, and the role of MR in atherosclerosis and tissue inflammation.


Assuntos
Aorta Torácica/metabolismo , Doenças da Aorta/metabolismo , Aterosclerose/metabolismo , Adesão Celular , Migração e Rolagem de Leucócitos , Macrófagos Peritoneais/metabolismo , Glicoproteínas de Membrana/metabolismo , Monócitos/metabolismo , Receptores de Mineralocorticoides/metabolismo , Adulto , Animais , Aorta Torácica/patologia , Doenças da Aorta/genética , Doenças da Aorta/patologia , Doenças da Aorta/prevenção & controle , Aterosclerose/genética , Aterosclerose/patologia , Aterosclerose/prevenção & controle , Adesão Celular/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Células HEK293 , Humanos , Hipoglicemia/tratamento farmacológico , Hipoglicemia/genética , Hipoglicemia/metabolismo , Migração e Rolagem de Leucócitos/efeitos dos fármacos , Macrófagos Peritoneais/patologia , Masculino , Glicoproteínas de Membrana/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Pessoa de Meia-Idade , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Monócitos/efeitos dos fármacos , Monócitos/patologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Receptores de Mineralocorticoides/efeitos dos fármacos , Receptores de Mineralocorticoides/genética , Fatores Sexuais , Transdução de Sinais , Espironolactona/uso terapêutico , Transcrição Gênica , Migração Transendotelial e Transepitelial , Resultado do Tratamento , Células U937 , Adulto Jovem
4.
Arterioscler Thromb Vasc Biol ; 39(8): 1588-1601, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31294624

RESUMO

OBJECTIVE: MR (mineralocorticoid receptor) activation is associated with cardiovascular ischemia in humans. This study explores the role of the MR in atherosclerotic mice of both sexes and identifies a sex-specific role for endothelial cell (EC)-MR in vascular inflammation. Approach and Results: In the AAV-PCSK9 (adeno-associated virus-proprotein convertase subtilisin/kexin type 9) mouse atherosclerosis model, MR inhibition attenuated vascular inflammation in males but not females. Further studies comparing male and female littermates with intact MR or EC-MR deletion revealed that although EC-MR deletion did not affect plaque size in either sex, it reduced aortic arch inflammation specifically in male mice as measured by flow cytometry. Moreover, MR-intact females had larger plaques but were protected from vascular inflammation compared with males. Intravital microscopy of the mesenteric vasculature demonstrated that EC-MR deletion attenuated TNFα (tumor necrosis factor α)-induced leukocyte slow rolling and adhesion in males, while females exhibited fewer leukocyte-endothelial interactions with no additional effect of EC-MR deletion. These effects corresponded with decreased TNFα-induced expression of the endothelial adhesion molecules ICAM-1 (intercellular adhesion molecule-1) and E-selectin in males with EC-MR deletion compared with MR-intact males and females of both genotypes. These observations were also consistent with MR and estrogen regulation of ICAM-1 transcription and E-selectin expression in primary cultured mouse ECs and human umbilical vein ECs. CONCLUSIONS: In male mice, EC-MR deletion attenuates leukocyte-endothelial interactions, plaque inflammation, and expression of E-selectin and ICAM-1, providing a potential mechanism by which the MR promotes vascular inflammation. In females, plaque inflammation and leukocyte-endothelial interactions are decreased relative to males and EC-MR deletion is not protective.


Assuntos
Aterosclerose/complicações , Células Endoteliais/fisiologia , Receptores de Mineralocorticoides/fisiologia , Vasculite/etiologia , Animais , Células Cultivadas , Selectina E/genética , Feminino , Molécula 1 de Adesão Intercelular/genética , Leucócitos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Caracteres Sexuais
5.
Phys Biol ; 16(2): 021002, 2019 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-30620933

RESUMO

Nanoparticles (NPs) constitute a powerful therapeutic platform with exciting prospects as potential inhibitors of amyloid-[Formula: see text] (Aß) aggregation, a process associated with Alzheimer's disease (AD). Researchers have synthesized and tested a large collection of NPs with disparate sizes, shapes, electrostatic properties and surface ligands that evoke a variety of responses on Aß aggregation. In spite of a decade of research on the NP-Aß system and many promising experimental results, NPs have failed to progress to any level of clinical trials for AD. A theoretical framework with which to approach this physical system is presented featuring two simple metrics, (1) the extent to which NPs adsorb Aß, and (2) the degree to which interaction with a NP alters Aß conformation relative to aggregation propensity. Most of our current understanding of these two interactions has been gained through experimentation, and many of these studies are reviewed herein. We also provide a potential roadmap for studies that we believe could produce viable NPs as an effective AD therapeutic platform.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Nanopartículas/uso terapêutico , Placa Amiloide/terapia , Humanos
6.
Crit Care Med ; 43(8): 1692-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25860203

RESUMO

OBJECTIVES: This article reports results of the first National Institutes of Health-funded prospective interfacility transport study to determine the effect of goal-directed therapy administered by a specialized pediatric team to critically ill children with the systemic inflammatory response syndrome. We hypothesized that goal-directed therapy during interfacility transport would decrease hospital length of stay, prevent multiple organ dysfunction, and reduce subsequent ICU interventions. DESIGN: Before-and-after intervention trial. SETTING: During interfacility transport of critically ill patients by a specialized pediatric transport team, back to a tertiary care children's hospital. PATIENTS: Before-and-after intervention trial. DESIGN: Interfacility pediatric transport patients, age 1 month to 17 years, with systemic inflammatory response syndrome. INTERVENTIONS: Prospective data were collected on all pediatric interfacility transport patients with systemic inflammatory response syndrome transported by the Angel One Transport team at Arkansas Children's Hospital. A 10-month data collection period was followed by institution of a goal-directed resuscitation protocol. Data were subsequently collected for 10 additional months followed by comparison of pre- and postintervention groups. All transport personnel underwent training with didactics and high-fidelity simulation until mastery with goal-directed resuscitation was achieved. MEASUREMENTS AND MAIN RESULTS: All transport patients were screened for systemic inflammatory response syndrome using established variables and 235 (123 preintervention and 112 postintervention) were enrolled. Univariate analysis revealed shorter hospital stay (11 ± 15 d vs 7 ± 10 d; p = 0.02) and fewer required therapeutic ICU interventions in the postintervention group (Therapeutic Intervention Scoring System-28 Scores, 19.4 ± 6.8 vs 17.3 ± 6.6; p = 0.04). ICU stay and prevalence of organ dysfunction were not statistically different. Multivariable analysis showed a 1.6-day (95% CI, 1.3-2.03; p = 0.02) decrease in hospital stay in the postintervention group. CONCLUSIONS: This study suggests that goal-directed therapy administered by a specialized pediatric transport team has the potential to impact the outcomes of critically ill children. Findings from this study should be confirmed across multiple institutions, but have the potential to impact the clinical outcomes of critically ill children with systemic inflammatory response syndrome.


Assuntos
Estado Terminal/terapia , Planejamento de Assistência ao Paciente/organização & administração , Transferência de Pacientes/organização & administração , Ressuscitação/métodos , Síndrome de Resposta Inflamatória Sistêmica/terapia , Criança , Pré-Escolar , Feminino , Hospitais Pediátricos , Humanos , Tempo de Internação , Masculino , Insuficiência de Múltiplos Órgãos/prevenção & controle , National Institutes of Health (U.S.) , Estudos Prospectivos , Índice de Gravidade de Doença , Fatores de Tempo , Estados Unidos
7.
J Intellect Disabil Res ; 59(2): 150-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23889770

RESUMO

BACKGROUND: The positive relationship between problem behaviours of children with additional complex needs and psychological distress in their caregivers has been widely evidenced. Fewer studies, however, have assessed the relationship between care recipients' problem behaviours and key physiological processes, relevant for the physical health status of their care providers. This study examined the psychological, endocrine and health corollaries of child problem behaviours in caregivers of children with autism and attention deficit hyperactivity disorder. METHODS: Caregivers (n = 18) completed self-report measures of psychological distress, child problem behaviours and incidences of commonly occurring ailments. To capture important parameters of the basal diurnal cortisol pattern, caregivers collected saliva samples at waking, 30 min post waking, 1200 h and 2200 h on two consecutive weekdays. RESULTS: Data revealed a positive relationship between caregivers' perceived levels of stress and problems with child conduct behaviours. In addition, caregivers who reported more problems with child emotional and hyperactivity behaviours displayed atypical cortisol patterns characterised by flatter diurnal cortisol slopes and reduced cortisol awakening response magnitude. Subjective reports of commonly occurring ailments were also greater in caregivers experiencing more problems with child emotional behaviours. CONCLUSIONS: These findings have implications for interventions that aim to improve the psychophysiological well-being of the caregiver by targeting problem behaviours of the care recipient.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Transtorno Autístico/psicologia , Cuidadores/psicologia , Nível de Saúde , Estresse Fisiológico/fisiologia , Estresse Psicológico/psicologia , Adolescente , Adulto , Cuidadores/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , Humanos , Hidrocortisona/metabolismo , Masculino , Pessoa de Meia-Idade , Saliva/metabolismo , Estresse Psicológico/metabolismo , Inquéritos e Questionários , Adulto Jovem
8.
J Hosp Infect ; 140: 34-39, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37562594

RESUMO

BACKGROUND: Monitoring hand hygiene compliance in the ambulatory setting remains a challenge because a healthcare trained observer loses line of sight once the examination room door closes. This quality improvement project focused on the implementation of a hand hygiene compliance improvement programme that is amenable to the routines and work flows of the ambulatory setting. METHODS: After a review of the literature, nursing leadership and infection prevention implemented the 'patient as the observer' hand hygiene programme across 32 ambulatory practices. RESULTS: Patients completed 281,000 observations with an overall compliance rate of ≥90%. The average overall compliance rate by role was 91% for providers, 89% for nurses, and 91% for medical assistants/technicians/others. A 92% compliance average was noted 'before caring for you' and 89% 'after caring for you' for providers, 90% and 87% for nurses, and 92% and 89% for medical assistants/technicians/others. DISCUSSION: This study demonstrated that the implementation of a hand hygiene compliance improvement programme using the patient as the observer can be adopted successfully in the ambulatory setting. CONCLUSION: Hand hygiene compliance can be monitored effectively in the ambulatory setting with the involvement of the patient as the observer.


Assuntos
Infecção Hospitalar , Higiene das Mãos , Humanos , Melhoria de Qualidade , Fidelidade a Diretrizes , Assistência Ambulatorial , Instalações de Saúde , Desinfecção das Mãos , Infecção Hospitalar/prevenção & controle , Controle de Infecções
9.
J Biomed Biotechnol ; 2012: 371414, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22811594

RESUMO

The Ilama is an important agricultural livestock in much of South America. The llama is increasing in popularity in the United States as a companion animal. Little work has been done to improve llama production using modern technology. A paucity of information is available regarding the llama genome. We report the construction of a llama bacterial artificial chromosome (BAC) library of about 196,224 clones in the vector pECBAC1. Using flow cytometry and bovine, human, mouse, and chicken as controls, we determined the llama genome size to be 2.4 × 109 bp. The average insert size of the library is 137.8 kb corresponding to approximately 9-fold genome coverage. Further studies are needed to further characterize the library and llama genome. We anticipate that this new library will help facilitate future genomic studies in the llama.


Assuntos
Camelídeos Americanos/genética , Cromossomos Artificiais Bacterianos/genética , Biblioteca Gênica , Tamanho do Genoma/genética , Genoma/genética , Genômica/métodos , Animais , Humanos
11.
JDR Clin Trans Res ; 6(2): 213-221, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32437630

RESUMO

INTRODUCTION: Ability to access needed dental care may vary among population subgroups. We assessed 1) the differences in the proportions of adults who reported unmet dental care needs in the past 12 months and the associated barriers (structural, financial, and cognitive) in 2015 to 2016 versus 2003 to 2004 by race/ethnicity and 2) the subgroups that are more likely to report unmet dental care needs. METHODS: Data of 10,029 respondents aged ≥19 y from the 2003-2004 and 2015-2016 National Health and Nutrition Examination Surveys were used. Chi-square tests assessed the differences in the proportions of adults who reported not getting the needed dental care between the periods. A multiple logistic regression model was run to identify characteristics that were significantly associated with unmet need after adjusting for other factors. RESULTS: Overall, 19.4% of the adults reported an unmet dental care need in 2015 to 2016, as compared with 21% in 2003 to 2004. The overall unmet dental care need decreased only in the Hispanic groups (34% to 28%, P = 0.045) between 2003-2004 and 2015-2016. Between the periods, unmet need decreased among Hispanics aged 19 to 64 y (35% to 28%, P = 0.02), Hispanics with some college education or above (33.5% to 21.0%, P = 0.008), and nonpoor Hispanic adults (29.8% to 20.4%, P = 0.048). No significant differences were observed in the proportions of adults reporting structural (P = 0.09), financial (P = 0.86), or cognitive (P = 0.07) barriers between the periods. When compared with their counterparts, nonelderly adults, women, Hispanics, adults with a high school education, those with less than a high school education, and poor adults were significantly more likely to report unmet dental care needs. CONCLUSIONS: Racial and ethnic disparities in accessing and receiving the needed dental care still exist. Financial barriers to dental care are the most commonly cited reasons for not getting the needed dental care. KNOWLEDGE TRANSFER STATEMENT: The results of the study will inform policy makers, public health planners, and dental professionals about subgroups that still face difficulty in receiving the dental care they need. Policy makers should develop new policies to mitigate the financial barriers that are still prevalent. Dental professionals can mitigate the public's cognitive and financial barriers by educating the community through outreach programs and by providing services to low-income populations at reduced charges or through alternative payment plans.


Assuntos
Etnicidade , Pobreza , Adulto , Idoso , Assistência Odontológica , Feminino , Humanos , Pessoa de Meia-Idade , Inquéritos Nutricionais , Adulto Jovem
12.
Pulm Circ ; 11(3): 20458940211025240, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34211700

RESUMO

Abnormalities that characterize pulmonary arterial hypertension include impairment in the structure and function of pulmonary vascular endothelial and smooth muscle cells. Aldosterone levels are elevated in human pulmonary arterial hypertension and in experimental pulmonary hypertension, while inhibition of the aldosterone-binding mineralocorticoid receptor attenuates pulmonary hypertension in multiple animal models. We explored the role of mineralocorticoid receptor in endothelial and smooth muscle cells in using cell-specific mineralocorticoid receptor knockout mice exposed to sugen/hypoxia-induced pulmonary hypertension. Treatment with the mineralocorticoid receptor inhibitor spironolactone significantly reduced right ventricular systolic pressure. However, this is not reproduced by selective mineralocorticoid receptor deletion in smooth muscle cells or endothelial cells. Similarly, spironolactone attenuated the increase in right ventricular cardiomyocyte area independent of vascular mineralocorticoid receptor with no effect on right ventricular weight or interstitial fibrosis. Right ventricular perivascular fibrosis was significantly decreased by spironolactone and this was reproduced by specific deletion of mineralocorticoid receptor from endothelial cells. Endothelial cell-mineralocorticoid receptor deletion attenuated the sugen/hypoxia-induced increase in the leukocyte-adhesion molecule, E-selectin, and collagen IIIA1 in the right ventricle. Spironolactone also significantly reduced pulmonary arteriolar muscularization, independent of endothelial cell-mineralocorticoid receptor or smooth muscle cell-mineralocorticoid receptor. Finally, the degree of pulmonary perivascular inflammation was attenuated by mineralocorticoid receptor antagonism and was fully reproduced by smooth muscle cell-specific mineralocorticoid receptor deletion. These studies demonstrate that in the sugen/hypoxia pulmonary hypertension model, systemic-mineralocorticoid receptor blockade significantly attenuates the disease and that mineralocorticoid receptor has cell-specific effects, with endothelial cell-mineralocorticoid receptor contributing to right ventricular perivascular fibrosis and smooth muscle cell-mineralocorticoid receptor participating in pulmonary vascular inflammation. As mineralocorticoid receptor antagonists are being investigated to treat pulmonary arterial hypertension, these findings support novel mechanisms and potential mineralocorticoid receptor targets that mediate therapeutic benefits in patients.

13.
Circ Heart Fail ; 14(2): e007279, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33517669

RESUMO

BACKGROUND: Mineralocorticoid receptor (MR) antagonists decrease heart failure (HF) hospitalization and mortality, but the mechanisms are unknown. Preclinical studies reveal that the benefits on cardiac remodeling and dysfunction are not completely explained by inhibition of MR in cardiomyocytes, fibroblasts, or endothelial cells. The role of MR in smooth muscle cells (SMCs) in HF has never been explored. METHODS: Male mice with inducible deletion of MR from SMCs (SMC-MR-knockout) and their MR-intact littermates were exposed to HF induced by 27-gauge transverse aortic constriction versus sham surgery. HF phenotypes and mechanisms were measured 4 weeks later using cardiac ultrasound, intracardiac pressure measurements, exercise testing, histology, cardiac gene expression, and leukocyte flow cytometry. RESULTS: Deletion of MR from SMC attenuated transverse aortic constriction-induced HF with statistically significant improvements in ejection fraction, cardiac stiffness, chamber dimensions, intracardiac pressure, pulmonary edema, and exercise capacity. Mechanistically, SMC-MR-knockout protected from adverse cardiac remodeling as evidenced by decreased cardiomyocyte hypertrophy and fetal gene expression, interstitial and perivascular fibrosis, and inflammatory and fibrotic gene expression. Exposure to pressure overload resulted in a statistically significant decline in cardiac capillary density and coronary flow reserve in MR-intact mice. These vascular parameters were improved in SMC-MR-knockout mice compared with MR-intact littermates exposed to transverse aortic constriction. CONCLUSIONS: These results provide a novel paradigm by which MR inhibition may be beneficial in HF by blocking MR in SMC, thereby improving cardiac blood supply in the setting of pressure overload-induced hypertrophy, which in turn mitigates the adverse cardiac remodeling that contributes to HF progression and symptoms.


Assuntos
Insuficiência Cardíaca/genética , Miócitos de Músculo Liso/metabolismo , Receptores de Mineralocorticoides/genética , Remodelação Ventricular/genética , Animais , Aorta/cirurgia , Pressão Arterial , Cardiomegalia/genética , Cardiomegalia/patologia , Cardiomegalia/fisiopatologia , Constrição Patológica , Modelos Animais de Doenças , Ecocardiografia , Técnicas de Inativação de Genes , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Camundongos , Músculo Liso Vascular/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Miócitos de Músculo Liso/patologia , Miócitos de Músculo Liso/fisiologia
14.
Anal Biochem ; 399(1): 30-8, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20018160

RESUMO

Evidence that membrane-associated amyloid aggregate growth can impart membrane damage represents one possible mechanism for the neurodegeneration associated with deposited amyloid-beta protein (Abeta) aggregates in the brains of Alzheimer's disease (AD) patients. This potential pathogenic event necessitates an understanding of the impact that cellular membrane composition may have on Abeta aggregate growth. In the current study, a quartz crystal microbalance (QCM) was employed to examine the growth of Abeta(1-40) aggregation intermediates on supported phospholipid bilayers (SPBs) assembled at the crystal surface. These surface-specific measurements illustrate that zwitterionic SPBs selectively bind aggregated but not monomeric protein, and these bound aggregates are capable of supporting nonsaturable reversible growth via monomer addition. Growth-capable Abeta(1-40) aggregation intermediates more readily bind SPBs composed of phospholipids with a greater degree of carbon saturation. Furthermore, kinetic analysis afforded by the quantitative real-time QCM measurements reveals that SPBs with greater saturation also better support the growth of bound Abeta(1-40) aggregation intermediates as a result of the slower dissociation of bound monomer rather than more efficient recognition between aggregate and monomeric protein. These findings correlate with epidemiological and experimental evidence that links increased dietary intake of polyunsaturated fatty acids to a reduced risk of AD.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Bicamadas Lipídicas/metabolismo , Fragmentos de Peptídeos/metabolismo , Fosfolipídeos/química , Quartzo , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/química , Ácidos Graxos/química , Bicamadas Lipídicas/química , Lipossomos/química , Fragmentos de Peptídeos/química , Fenilenodiaminas/química , Fosfatidilcolinas/química
15.
Pharmacol Ther ; 203: 107387, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31271793

RESUMO

Cardiovascular disease remains the leading cause of death for both men and women. The observation that premenopausal women are protected from cardiovascular disease relative to age-matched men, and that this protection is lost with menopause, has led to extensive study of the role of sex steroid hormones in the pathogenesis of cardiovascular disease. However, the molecular basis for sex differences in cardiovascular disease is still not fully understood, limiting the ability to tailor therapies to male and female patients. Therefore, there is a growing need to investigate molecular pathways outside of traditional sex hormone signaling to fully understand sex differences in cardiovascular disease. Emerging evidence points to the mineralocorticoid receptor (MR), a steroid hormone receptor activated by the adrenal hormone aldosterone, as one such mediator of cardiovascular disease risk, potentially serving as a sex-dependent link between cardiovascular risk factors and disease. Enhanced activation of the MR by aldosterone is associated with increased risk of cardiovascular disease. Emerging evidence implicates the MR specifically within the endothelial cells lining the blood vessels in mediating some of the sex differences observed in cardiovascular pathology. This review summarizes the available clinical and preclinical literature concerning the role of the MR in the pathophysiology of endothelial dysfunction, hypertension, atherosclerosis, and heart failure, with a special emphasis on sex differences in the role of endothelial-specific MR in these pathologies. The available data regarding the molecular mechanisms by which endothelial-specific MR may contribute to sex differences in cardiovascular disease is also summarized. A paradigm emerges from synthesis of the literature in which endothelial-specific MR regulates vascular function in a sex-dependent manner in response to cardiovascular risk factors to contribute to disease. Limitations in this field include the relative paucity of women in clinical trials and, until recently, the nearly exclusive use of male animals in preclinical investigations. Enhanced understanding of the sex-specific roles of endothelial MR could lead to novel mechanistic insights underlying sex differences in cardiovascular disease incidence and outcomes and could identify additional therapeutic targets to effectively treat cardiovascular disease in men and women.


Assuntos
Doenças Cardiovasculares/metabolismo , Endotélio Vascular/metabolismo , Receptores de Mineralocorticoides/metabolismo , Caracteres Sexuais , Animais , Humanos
16.
Biomed Mater ; 14(3): 035007, 2019 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-30795002

RESUMO

3D printing is a rapid and accessible fabrication technology that engenders creative custom design solutions for cell scaffolds, perfusion systems and cell culture systems for tissue engineering. Critical to its success is the biocompatibility of the materials used, which should allow long-term tissue culture without affecting cell viability or inducing an inflammatory response for in vitro and in vivo applications. Polyjet 3D printers offer arguably the highest resolution with the fewest design constraints of any commercially available 3D printing systems. Although widely used for rapid-prototyping of medical devices and 3D anatomical modelling, polyjet printing has not been adopted by the tissue engineering field, largely due to the cytotoxicity of leachates from the printed parts. Biocompatibility in the context of cell culture is not commonly addressed for polyjet materials, as they tend to be optimised for their ability to fabricate complex structures. In order to study the potential issues surrounding the leaching of toxins, we prepared cell culture substrates using the commercially available MED610 photopolymer. The substrates were cleaned using either the manufacturer-specified 'biocompatible' washing procedures, or a novel protocol incorporating a sonication in isopropanol and water step. We then compared the effectiveness of these both in vitro and in vivo. Using primary mouse myoblast cultures, the manufacturer's protocol led to inconsistent and poorer cell viability when compared to the sonication protocol (p = 0.0002 at 48 h after indirect exposure). Subdermal implantation of MED610 into nude rats demonstrated a significant foreign body response with a greater number of giant cells (p = 0.0161) and foreign bodies (p = 0.0368) when compared to the sonication protocol, which was comparable to the control (sham) groups. These results present an improved, cytocompatible cleaning protocol of printable photopolymers to facilitate creative 3D-printed custom designs for cell culture systems for both in vitro and in vivo tissue engineering applications.


Assuntos
Materiais Biocompatíveis/química , Bioimpressão/instrumentação , Polímeros/química , Impressão Tridimensional/instrumentação , Engenharia Tecidual/instrumentação , Animais , Bioimpressão/métodos , Técnicas de Cultura de Células , Sobrevivência Celular , Células Cultivadas , Teste de Materiais , Camundongos , Camundongos Endogâmicos C57BL , Fotoquímica , Ratos , Ratos Nus , Solventes , Sonicação , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Microtomografia por Raio-X
17.
J Appl Microbiol ; 104(5): 1239-43, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18217939

RESUMO

The role of moulds in the spoilage of fresh fruits and vegetables is discussed. Although the major problems are economic with a significant loss of useful food materials, there are a few examples implicating a role for mycotoxins in the safety of fresh fruits. The significance of the mycotoxins patulin, ochratoxin and tenuazonic acid will be reviewed.


Assuntos
Microbiologia de Alimentos , Frutas/microbiologia , Fungos/fisiologia , Micotoxinas/toxicidade , Verduras/microbiologia , Humanos , Ocratoxinas/toxicidade , Patulina/toxicidade , Ácido Tenuazônico/toxicidade
18.
J Int Med Res ; 36(2): 211-21, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18380929

RESUMO

Despite considerable research and constantly emerging treatment modalities, the mortality associated with acute respiratory distress syndrome (ARDS) has remained virtually unchanged over the last decade. Clinical studies have been unable to show a reduction in mortality for most therapeutic interventions except for low tidal volume ventilation. Failure to prove a mortality benefit might be a result of the varying severity of ARDS in the patients studied. Nevertheless, positive responses to single supportive measures (inhaled nitric oxide, prone positioning and extracorporeal membrane oxygenation) have been demonstrated in multiple trials. Criteria for administration, weaning and discontinuation of these supportive interventions have never been described in detail. In this context, implementation of an evidence-based algorithm might facilitate clinical management of severe ARDS. This review summarizes the current evidence base and proposes a new treatment algorithm that aims to prioritize the administration of advanced strategies in a multimodal approach for ARDS.


Assuntos
Algoritmos , Medicina Baseada em Evidências/métodos , Síndrome do Desconforto Respiratório/terapia , Terapia Combinada , Medicina Baseada em Evidências/tendências , Humanos , Síndrome do Desconforto Respiratório/diagnóstico , Síndrome do Desconforto Respiratório/fisiopatologia , Índice de Gravidade de Doença
19.
J Am Heart Assoc ; 7(4)2018 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-29453308

RESUMO

BACKGROUND: The incidence of obesity is rising, particularly among women. Microvascular dysfunction is more common with female sex, obesity, and hyperlipidemia and predicts adverse cardiovascular outcomes, but the molecular mechanisms are unclear. Because obesity is associated with mineralocorticoid receptor (MR) activation, we tested the hypothesis that MR in endothelial cells contribute to sex differences in resistance vessel dysfunction in response to cardiometabolic risk factors. METHODS AND RESULTS: Male and female endothelial cell-specific MR knockout mice and MR-intact littermates were randomized to high-fat-diet-induced obesity or obesity with hyperlipidemia induced by adeno-associated virus-based vector targeting transfer of the mutant stable form (DY mutation) of the human PCSK9 (proprotein convertase subtilisin/kexin type 9) gene and compared with control diet. Female but not male mice were sensitive to obesity-induced endothelial dysfunction, whereas endothelial function was impaired in obese hyperlipidemic males and females. In males, obesity or hyperlipidemia decreased the nitric oxide component of vasodilation without altering superoxide production or endothelial nitric oxide synthase expression or phosphorylation. Decreased nitric oxide content in obese males was overcome by enhanced endothelium-derived hyperpolarization-mediated relaxation along with increased SK3 expression. Conversely, in females, endothelium-derived hyperpolarization was significantly impaired by obesity with lower IK1 expression and by hyperlipidemia with lower IK1 and SK3 expression, loss of H2O2-mediated vasodilation, and increased superoxide production. Endothelial cell-MR deletion prevented endothelial dysfunction induced by risk factors only in females. Rather than restoring endothelium-derived hyperpolarization in females, endothelial cell-MR deletion enhanced nitric oxide and prevented hyperlipidemia-induced oxidative stress. CONCLUSIONS: These data reveal distinct mechanisms driving resistance vessel dysfunction in males versus females and suggest that personalized treatments are needed to prevent the progression of vascular disease in the setting of obesity, depending on both the sex and the metabolic profile of each patient.


Assuntos
Endotélio Vascular/fisiopatologia , Hiperlipidemias/fisiopatologia , Artérias Mesentéricas/fisiopatologia , Obesidade/fisiopatologia , Vasodilatação , Animais , Fatores Biológicos/metabolismo , Modelos Animais de Doenças , Endotélio Vascular/metabolismo , Feminino , Hiperlipidemias/genética , Hiperlipidemias/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/metabolismo , Masculino , Artérias Mesentéricas/metabolismo , Camundongos Knockout , Mutação , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Obesidade/genética , Obesidade/metabolismo , Estresse Oxidativo , Fosforilação , Pró-Proteína Convertase 9/genética , Receptores de Mineralocorticoides/genética , Receptores de Mineralocorticoides/metabolismo , Fatores Sexuais , Canais de Potássio Ativados por Cálcio de Condutância Baixa/metabolismo , Superóxidos/metabolismo
20.
Front Cardiovasc Med ; 5: 81, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30038907

RESUMO

Objective: Elevated levels of the hormone aldosterone are associated with increased risk of myocardial infarction and stroke in humans and increased progression and inflammation of atherosclerotic plaques in animal models. Aldosterone acts through the mineralocorticoid receptor (MR) which is expressed in vascular smooth muscle cells (SMCs) where it promotes SMC calcification and chemokine secretion in vitro. The objective of this study is to explore the role of the MR specifically in SMCs in the progression of atherosclerosis and the associated vascular inflammation in vivo in the apolipoprotein E knockout (ApoE-/-) mouse model. Methods and Results: Male ApoE-/- mice were bred with mice in which MR could be deleted specifically from SMCs by tamoxifen injection. The resulting atheroprone SMC-MR-KO mice were compared to their MR-Intact littermates after high fat diet (HFD) feeding for 8 or 16 weeks or normal diet for 12 months. Body weight, tail cuff blood pressure, heart and spleen weight, and serum levels of glucose, cholesterol, and aldosterone were measured for all mice at the end of the treatment period. Serial histologic sections of the aortic root were stained with Oil Red O to assess plaque size, lipid content, and necrotic core area; with PicroSirius Red for quantification of collagen content; by immunofluorescent staining with anti-Mac2/Galectin-3 and anti-smooth muscle α-actin antibodies to assess inflammation and SMC marker expression; and with Von Kossa stain to detect plaque calcification. In the 16-week HFD study, these analyses were also performed in sections from the brachiocephalic artery. Flow cytometry of cell suspensions derived from the aortic arch was also performed to quantify vascular inflammation after 8 and 16 weeks of HFD. Deletion of the MR specifically from SMCs did not significantly change plaque size, lipid content, necrotic core, collagen content, inflammatory staining, actin staining, or calcification, nor were there differences in the extent of vascular inflammation between MR-Intact and SMC-MR-KO mice in the three experiments. Conclusion: SMC-MR does not directly contribute to the formation, progression, or inflammation of atherosclerotic plaques in the ApoE-/- mouse model of atherosclerosis. This indicates that the MR in non-SMCs mediates the pro-atherogenic effects of MR activation.

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