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1.
Sci Total Environ ; 947: 174408, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38972407

RESUMO

Big data have become increasingly important for policymakers and scientists but have yet to be employed for the development of spatially specific groundwater contamination indices or protecting human and environmental health. The current study sought to develop a series of indices via analyses of three variables: Non-E. coli coliform (NEC) concentration, E. coli concentration, and the calculated NEC:E. coli concentration ratio. A large microbial water quality dataset comprising 1,104,094 samples collected from 292,638 Ontarian wells between 2010 and 2021 was used. Getis-Ord Gi* (Gi*), Local Moran's I (LMI), and space-time scanning were employed for index development based on identified cluster recurrence. Gi* and LMI identify hot and cold spots, i.e., spatially proximal subregions with similarly high or low contamination magnitudes. Indices were statistically compared with mapped well density and age-adjusted enteric infection rates (i.e., campylobacteriosis, cryptosporidiosis, giardiasis, verotoxigenic E. coli (VTEC) enteritis) at a subregional (N = 298) resolution for evaluation and final index selection. Findings suggest that index development via Gi* represented the most efficacious approach. Developed Gi* indices exhibited no correlation with well density, implying that indices are not biased by rural population density. Gi* indices exhibited positive correlations with mapped infection rates, and were particularly associated with higher bacterial (Campylobacter, VTEC) infection rates among younger sub-populations (p < 0.05). Conversely, no association was found between developed indices and giardiasis rates, an infection not typically associated with private groundwater contamination. Findings suggest that a notable proportion of bacterial infections are associated with groundwater and that the developed Gi* index represents an appropriate spatiotemporal reflection of long-term groundwater quality. Bacterial infection correlations with the NEC:E. coli ratio index (p < 0.001) were markedly different compared to correlations with the E. coli index, implying that the ratio may supplement E. coli monitoring as a groundwater assessment metric capable of elucidating contamination mechanisms. This study may serve as a methodological blueprint for the development of big data-based groundwater contamination indices across the globe.

3.
Sci Data ; 11(1): 656, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38906875

RESUMO

During the COVID-19 pandemic, the Province of Ontario, Canada, launched a wastewater surveillance program to monitor SARS-CoV-2, inspired by the early work and successful forecasts of COVID-19 waves in the city of Ottawa, Ontario. This manuscript presents a dataset from January 1, 2021, to March 31, 2023, with RT-qPCR results for SARS-CoV-2 genes and PMMoV from 107 sites across all 34 public health units in Ontario, covering 72% of the province's and 26.2% of Canada's population. Sampling occurred 2-7 times weekly, including geographical coordinates, serviced populations, physico-chemical water characteristics, and flowrates. In doing so, this manuscript ensures data availability and metadata preservation to support future research and epidemic preparedness through detailed analyses and modeling. The dataset has been crucial for public health in tracking disease locally, especially with the rise of the Omicron variant and the decline in clinical testing, highlighting wastewater-based surveillance's role in estimating disease incidence in Ontario.


Assuntos
COVID-19 , SARS-CoV-2 , Águas Residuárias , Ontário/epidemiologia , COVID-19/epidemiologia , Águas Residuárias/virologia , Humanos , Pandemias , Carga Viral
4.
bioRxiv ; 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38659888

RESUMO

Intrinsically photosensitive retinal ganglion cells (ipRGCs) play a crucial role in several physiological light responses. In this study we generate a new Opn4cre knock-in allele (Opn4cre(DSO)), in which cre is placed immediately downstream of the Opn4 start codon. This approach aims to faithfully reproduce endogenous Opn4 expression and improve compatibility with widely used reporters. We evaluated the efficacy and sensitivity of Opn4cre(DSO) for labeling in retina and brain, and provide an in-depth comparison with the extensively utilized Opn4cre(Saha) line. Through this characterization, Opn4cre(DSO) demonstrated higher specificity in labeling ipRGCs, with minimal recombination escape. Leveraging a combination of electrophysiological, molecular, and morphological analyses, we confirmed its sensitivity in detecting all ipRGC types (M1-M6). Using this new tool, we describe the topographical distributions of ipRGC types across the retinal landscape, uncovering distinct ventronasal biases for M5 and M6 types, setting them apart from their M1-M4 counterparts. In the brain, we find vastly different labeling patterns between lines, with Opn4cre(DSO) only labeling ipRGC axonal projections to their targets. The combination of off-target effects of Opn4cre(Saha) across the retina and brain, coupled with diminished efficiencies of both Cre lines when coupled to less sensitive reporters, underscores the need for careful consideration in experimental design and validation with any Opn4cre driver. Overall, the Opn4cre(DSO) mouse line represents an improved tool for studying ipRGC function and distribution, offering a means to selectively target these cells to study light-regulated behaviors and physiology.

5.
Blood Adv ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640200

RESUMO

Etavopivat is an investigational, once-daily, oral, selective erythrocyte pyruvate kinase (PKR) activator. A multicenter, randomized, placebo-controlled, double-blind, 3-part, phase 1 study (https://clinicaltrials.gov/study/NCT03815695) was conducted to characterize the safety and clinical activity of etavopivat. Thirty-six patients with sickle cell disease (SCD) were enrolled into 4 cohorts: one single-dose; two multiple ascending doses; one open-label [OL]. In the OL cohort, 15 patients (median age 33.0 [range, 17‒55] years received 400-mg etavopivat once daily for 12 weeks; 14 completed treatment. Consistent with the mechanism of PKR activation, increases in ATP and decreases in 2,3 diphosphoglycerate were observed and sustained over 12 weeks' treatment. This translated clinically to an increase in hemoglobin (mean maximal increase 1.6 [range, 0.8‒2.8] g/dL), with >1 g/dL increase in 11 (73%) patients during treatment. Additionally, oxygen tension at which hemoglobin is 50% saturated was reduced (P=.0007) with concomitant shift in point-of-sickling (P=.0034) to lower oxygen tension in oxygen-gradient ektacytometry. Hemolysis markers (absolute reticulocyte count, indirect bilirubin, lactate dehydrogenase) decreased from baseline, along with matrix metalloproteinase-9 and erythropoietin. In the OL cohort, adverse events (AEs) were mostly grade 1/2, consistent with underlying SCD; 5 patients had serious AEs. Vaso-occlusive pain episode was the most common treatment-emergent AE (n=7) in the OL cohort. In this first study of etavopivat in SCD, 400 mg once daily for 12 weeks was well-tolerated, resulting in rapid and sustained increases in hemoglobin, improved RBC physiology, and decreased hemolysis.

6.
Blood ; 143(21): 2145-2151, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38364110

RESUMO

ABSTRACT: Voxelotor is an inhibitor of sickle hemoglobin polymerization that is used to treat sickle cell disease. Although voxelotor has been shown to improve anemia, the clinical benefit on the brain remains to be determined. This study quantified the cerebral hemodynamic effects of voxelotor in children with sickle cell anemia (SCA) using noninvasive diffuse optical spectroscopies. Specifically, frequency-domain near-infrared spectroscopy combined with diffuse correlation spectroscopy were used to noninvasively assess regional oxygen extraction fraction (OEF), cerebral blood volume, and an index of cerebral blood flow (CBFi). Estimates of CBFi were first validated against arterial spin-labeled magnetic resonance imaging (ASL-MRI) in 8 children with SCA aged 8 to 18 years. CBFi was significantly positively correlated with ASL-MRI-measured blood flow (R2 = 0.651; P = .015). Next, a single-center, open-label pilot study was completed in 8 children with SCA aged 4 to 17 years on voxelotor, monitored before treatment initiation and at 4, 8, and 12 weeks (NCT05018728). By 4 weeks, both OEF and CBFi significantly decreased, and these decreases persisted to 12 weeks (both P < .05). Decreases in CBFi were significantly correlated with increases in blood hemoglobin (Hb) concentration (P = .025), whereas the correlation between decreases in OEF and increases in Hb trended toward significance (P = .12). Given that previous work has shown that oxygen extraction and blood flow are elevated in pediatric SCA compared with controls, these results suggest that voxelotor may reduce cerebral hemodynamic impairments. This trial was registered at www.ClinicalTrials.gov as #NCT05018728.


Assuntos
Anemia Falciforme , Circulação Cerebrovascular , Oxigênio , Humanos , Anemia Falciforme/sangue , Criança , Adolescente , Masculino , Feminino , Oxigênio/sangue , Oxigênio/metabolismo , Pré-Escolar , Imageamento por Ressonância Magnética/métodos , Pirazinas/uso terapêutico , Pirazinas/administração & dosagem , Projetos Piloto , Benzaldeídos/uso terapêutico , Benzaldeídos/farmacologia , Benzaldeídos/administração & dosagem , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Pirazóis
7.
Water Res ; 253: 121207, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38401469

RESUMO

Wastewater-based epidemiology (WBE) is an emerging, practical surveillance tool for monitoring community levels of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, SC2). However, a paucity of data exists regarding SARS-CoV-2 and viral biomarker behaviour in aqueous and wastewater environments. Therefore, there is a pressing need to develop efficient and robust methods that both improve method sensitivity and reduce time and cost. We present a novel method for SARS-CoV-2, Human Coronavirus 229E (229E), and Pepper Mild Mottle Virus (PMMoV) recovery utilizing surface charge-based attraction via the branched cationic polymer, polyethylenimine (PEI). Initially, dose-optimization experiments demonstrated that low concentrations of PEI (0.001% w/v) proved most effective at flocculating suspended viruses and viral material, including additional unbound SC2 viral fragments and/or RNA from raw wastewater. A design-of-experiments (DOE) approach was used to optimize virus and/or viral material aggregation behaviour and recovery across varying aqueous conditions, revealing pH as a major influence on recoverability in this system, combinatorially due to both a reduction in viral material surface charge and increased protonation of PEI-bound amine groups. Overall, this method has shown great promise in significantly improving quantitative viral recovery, providing a straightforward and effective augmentation to standard centrifugation techniques.


Assuntos
COVID-19 , RNA Viral , Humanos , SARS-CoV-2 , Polietilenoimina , Águas Residuárias
8.
Sci Rep ; 14(1): 3728, 2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355869

RESUMO

Wastewater surveillance of coronavirus disease 2019 (COVID-19) commonly applies reverse transcription-quantitative polymerase chain reaction (RT-qPCR) to quantify severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA concentrations in wastewater over time. In most applications worldwide, maximal sensitivity and specificity of RT-qPCR has been achieved, in part, by monitoring two or more genomic loci of SARS-CoV-2. In Ontario, Canada, the provincial Wastewater Surveillance Initiative reports the average copies of the CDC N1 and N2 loci normalized to the fecal biomarker pepper mild mottle virus. In November 2021, the emergence of the Omicron variant of concern, harboring a C28311T mutation within the CDC N1 probe region, challenged the accuracy of the consensus between the RT-qPCR measurements of the N1 and N2 loci of SARS-CoV-2. In this study, we developed and applied a novel real-time dual loci quality assurance and control framework based on the relative difference between the loci measurements to the City of Ottawa dataset to identify a loss of sensitivity of the N1 assay in the period from July 10, 2022 to January 31, 2023. Further analysis via sequencing and allele-specific RT-qPCR revealed a high proportion of mutations C28312T and A28330G during the study period, both in the City of Ottawa and across the province. It is hypothesized that nucleotide mutations in the probe region, especially A28330G, led to inefficient annealing, resulting in reduction in sensitivity and accuracy of the N1 assay. This study highlights the importance of implementing quality assurance and control criteria to continually evaluate, in near real-time, the accuracy of the signal produced in wastewater surveillance applications that rely on detection of pathogens whose genomes undergo high rates of mutation.


Assuntos
Vigilância Epidemiológica Baseada em Águas Residuárias , Águas Residuárias , Alelos , Mutação , Ontário/epidemiologia , SARS-CoV-2/genética , RNA Viral/genética
10.
Toxins (Basel) ; 15(11)2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37999491

RESUMO

The survival of Escherichia coli (E. coli) bacteria, the most common faecal indicator bacteria (FIB), may be significantly affected by cyanobacteria present during a harmful algal bloom (HAB). Therefore, the effect of Microcystis on the survival of FIB E.coli and coliforms was investigated. Microcosms containing two species of Microcystis (M. aeruginosa and M. smithii) were established and then inoculated with four reference strains of E. coli (ATCC 25922, 8739, 51813, and 11775) to explore the cyanobacteria-bacteria dynamics at a laboratory setting. Monitoring over several days showed normal growth of Microcystis, with or without the presence of E. coli. However, Microcystis was shown to dramatically decrease the survival of E. coli over time. Analysis of microcystin production by Microcystis was found to correlate with loss of E. coli, suggesting a toxic effect of microcystins on E. coli bacteria. This phenomenon was also demonstrated for a natural consortium of E. coli and coliform bacteria by inoculating with contaminated lake water. The results indicate that the use of E. coli as FIB may be greatly compromised in the presence of Microcystis spp. such as during a HAB when associated toxins are produced.


Assuntos
Cianobactérias , Microcystis , Escherichia coli , Microcistinas/toxicidade , Proliferação Nociva de Algas , Lagos/microbiologia
11.
Clin Ter ; 174(Suppl 2(6)): 243-248, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37994771

RESUMO

Abstract: The worldwide infertility crisis and the increase in mortality and morbidity among infants, due to preterm births and associated complications, have stimulated research into artificial placenta (AP) and artificial womb (AW) technology as novel solutions. These technologies mimic the natural environment provided in the mother's womb, using chambers that ensure the supply of nutrients to the fetus and disposal of waste substances through an appropriate mechanism. This review aims to highlight the background of AP and AW technologies, revisit their historical development and proposed applications, and discuss challenges and bioethical and moral issues. Further research is required to investigate any negative effects of these new technologies, and ethical concerns pertaining to the structure and operation of this newly developed technology must be addressed and resolved prior to its introduction to the public sphere.


Assuntos
Placenta , Útero , Gravidez , Recém-Nascido , Lactente , Feminino , Humanos , Feto , Tecnologia
12.
Clin Ter ; 174(Suppl 2(6)): 227-229, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37994768

RESUMO

Abstract: Professor Derek Pheby's passing in November 2022 marked a profound loss for the scientific community. Professor Derek Pheby, a stalwart figure in the fields of autoimmune diseases and bioethics, was known for his dedication to scientific research and patients' support, particularly for those affected by paraneoplastic autoimmune syndromes. Professor Pheby made significant contributions to research, especially about Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). His leadership of the ME Biobank and scientific coordination of EUROMENE demonstrated his commitment to pushing boundaries and fostering international collaborations. Professor Pheby's scientific work addressed various aspects of ME/CFS, from physician education to patient needs, the development of a post-mortem tissue bank, and effective treatments. Beyond his medical career, Professor Pheby was a crucial member of the Independent Ethics Committee of MAGI, he was a poet, humanitarian, and advocate for child protection. His generosity and boundless spirit left an enduring legacy, fostering innovative research in the pursuit of combating autoimmune diseases.

13.
Clin Ter ; 174(Suppl 2(6)): 230-235, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37994769

RESUMO

Abstract: This scholarly article delves into the multifaceted domains of human cloning, encompassing its biological underpinnings, ethical dimensions, and broader societal implications. The exposition commences with a succinct historical and contextual overview of human cloning, segueing into an in-depth exploration of its biological intri-cacies. Central to this biological scrutiny is a comprehensive analysis of somatic cell nuclear transfer (SCNT) and its assorted iterations. The accomplishments and discoveries in cloning technology, such as successful animal cloning operations and advances in the efficiency and viability of cloned embryos, are reviewed. Future improvements, such as reprogramming procedures and gene editing technology, are also discussed. The discourse extends to ethical quandaries intrinsic to human cloning, entailing an extensive contemplation of values such as human dignity, autonomy, and safety. Furthermore, the ramifications of human cloning on a societal plane are subjected to scrutiny, with a dedicated emphasis on ramifications encompassing personal identity, kinship connections, and the fundamental notion of maternity. Culminating the analysis is a reiteration of the imperative to develop and govern human cloning technology judiciously and conscientiously. Finally, it discusses several ethical and practical issues, such as safety concerns, the possibility of exploitation, and the erosion of human dignity, and emphasizes the significance of carefully considering these issues.


Assuntos
Clonagem de Organismos , Técnicas de Transferência Nuclear , Animais , Feminino , Humanos , Gravidez , Autoimagem , Biologia
16.
Int J Mol Sci ; 24(11)2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37298696

RESUMO

This study analyzed microarray data of right ventricular (RV) tissue from rats exposed to pulmonary embolism to understand the initial dynamic transcriptional response to mechanical stress and compare it with experimental pulmonary hypertension (PH) models. The dataset included samples harvested from 55 rats at 11 different time points or RV locations. We performed principal component analysis (PCA) to explore clusters based on spatiotemporal gene expression. Relevant pathways were identified from fast gene set enrichment analysis using PCA coefficients. The RV transcriptomic signature was measured over several time points, ranging from hours to weeks after an acute increase in mechanical stress, and was found to be highly dependent on the severity of the initial insult. Pathways enriched in the RV outflow tracts of rats at 6 weeks after severe PE share many commonalities with experimental PH models, but the transcriptomic signature at the RV apex resembles control tissue. The severity of the initial pressure overload determines the trajectory of the transcriptomic response independent of the final afterload, but this depends on the location where the tissue is biopsied. Chronic RV pressure overload due to PH appears to progress toward similar transcriptomic endpoints.


Assuntos
Hipertensão Pulmonar , Embolia Pulmonar , Ratos , Animais , Ventrículos do Coração/metabolismo , Transcriptoma , Perfilação da Expressão Gênica , Hipertensão Pulmonar/metabolismo , Modelos Animais de Doenças , Remodelação Ventricular
17.
Front Cell Dev Biol ; 11: 1076458, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37035245

RESUMO

All-trans-retinoic acid (ATRA)-based differentiation therapy of acute promyelocytic leukemia (APL) represents one of the most clinically effective examples of precision medicine and the first example of targeted oncoprotein degradation. The success of ATRA in APL, however, remains to be translated to non-APL acute myeloid leukemia (AML). We previously showed that aberrant histone modifications, including histone H3 lysine 4 (H3K4) and lysine 27 (H3K27) methylation, were associated with this lack of response and that epigenetic therapy with small molecule inhibitors of the H3K4 demethylase LSD1/KDM1A could reprogram AML cells to respond to ATRA. Serving as the enzymatic component of Polycomb Repressive Complex 2, EZH2/KMT6A methyltransferase plays a critical role in normal hematopoiesis by affecting the balance between self-renewal and differentiation. The canonical function of EZH2 is methylation of H3K27, although important non-canonical roles have recently been described. EZH2 mutation or deregulated expression has been conclusively demonstrated in the pathogenesis of AML and response to treatment, thus making it an attractive therapeutic target. In this study, we therefore investigated whether inhibition of EZH2 might also improve the response of non-APL AML cells to ATRA-based therapy. We focused on GSK-343, a pyridone-containing S-adenosyl-L-methionine cofactor-competitive EZH2 inhibitor that is representative of its class, and HKMTI-1-005, a substrate-competitive dual inhibitor targeting EZH2 and the closely related G9A/GLP H3K9 methyltransferases. We found that treatment with HKMTI-1-005 phenocopied EZH2 knockdown and was more effective in inducing differentiation than GSK-343, despite the efficacy of GSK-343 in terms of abolishing H3K27 trimethylation. Furthermore, transcriptomic analysis revealed that in contrast to treatment with GSK-343, HKMTI-1-005 upregulated the expression of differentiation pathway genes with and without ATRA, while downregulating genes associated with a hematopoietic stem cell phenotype. These results pointed to a non-canonical role for EZH2, which was supported by the finding that EZH2 associates with the master regulator of myeloid differentiation, RARα, in an ATRA-dependent manner that was enhanced by HKMTI-1-005, possibly playing a role in co-regulator complex exchange during transcriptional activation. In summary, our results strongly suggest that addition of HKMTI-1-005 to ATRA is a new therapeutic approach against AML that warrants further investigation.

18.
J Hosp Infect ; 136: 110-117, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37105259

RESUMO

BACKGROUND: Healthcare workers treating SARS-CoV-2 patients are at risk of infection by respiratory exposure to patient-emitted, virus-laden aerosols. Source control devices such as ventilated patient isolation hoods have been shown to limit the dissemination of non-infectious airborne particles in laboratory tests, but data on their performance in mitigating the airborne transmission risk of infectious viruses are lacking. AIM: We used an infectious airborne virus to quantify the ability of a ventilated hood to reduce infectious virus exposure in indoor environments. METHODS: We nebulized 109 plaque forming units (pfu) of bacteriophage PhiX174 virus into a ∼30-m3 room when the hood was active or inactive. The airborne concentration of infectious virus was measured by BioSpot-VIVAS and settle plates using plaque assay quantification on the bacterial host Escherichia coli C. The airborne particle number concentration (PNC) was also monitored continuously using an optical particle sizer. FINDINGS: The median airborne viral concentration in the room reached 1.41 × 105 pfu/m3 with the hood inactive. When active, the hood reduced infectious virus concentration in air samples by 374-fold. The deposition of infectious virus on the surface of settle plates was reduced by 87-fold. This was associated with a 109-fold reduction in total airborne particle number escape rate. CONCLUSION: A personal ventilation hood significantly reduced airborne particle escape, considerably lowering infectious virus contamination in an indoor environment. Our findings support the further development of source control devices to mitigate nosocomial infection risk among healthcare workers exposed to airborne viruses in clinical settings.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/prevenção & controle , Carga Viral , Respiração Artificial , Aerossóis e Gotículas Respiratórios
19.
Am J Respir Cell Mol Biol ; 69(1): 73-86, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36944195

RESUMO

Hypoxia-inducible factor (HIF) has received much attention as a potential pulmonary hypertension (PH) treatment target because inhibition of HIF reduces the severity of established PH in rodent models. However, the limitations of small-animal models of PH in predicting the therapeutic effects of pharmacologic interventions in humans PH are well known. Therefore, we sought to interrogate the role of HIFs in driving the activated phenotype of PH cells from human and bovine vessels. We first established that pulmonary arteries (PAs) from human and bovine PH lungs exhibit markedly increased expression of direct HIF target genes (CA9, GLUT1, and NDRG1), as well as cytokines/chemokines (CCL2, CSF2, CXCL12, and IL6), growth factors (FGF1, FGF2, PDGFb, and TGFA), and apoptosis-resistance genes (BCL2, BCL2L1, and BIRC5). The expression of the genes found in the intact PAs was determined in endothelial cells, smooth muscle cells, and fibroblasts cultured from the PAs. The data showed that human and bovine pulmonary vascular fibroblasts from patients or animals with PH (termed PH-Fibs) were the cell type that exhibited the highest level and the most significant increases in the expression of cytokines/chemokines and growth factors. In addition, we found that human, but not bovine, PH-Fibs exhibit consistent misregulation of HIFα protein stability, reduced HIF1α protein hydroxylation, and increased expression of HIF target genes even in cells grown under normoxic conditions. However, whereas HIF inhibition reduced the expression of direct HIF target genes, it had no impact on other "persistently activated" genes. Thus, our study indicated that HIF inhibition alone is not sufficient to reverse the persistently activated phenotype of human and bovine PH-Fibs.


Assuntos
Hipertensão Pulmonar , Animais , Humanos , Hipertensão Pulmonar/metabolismo , Células Endoteliais/metabolismo , Fenótipo , Citocinas/metabolismo , Artéria Pulmonar/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , Hipóxia/complicações , Fibroblastos/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Células Cultivadas
20.
Am J Physiol Heart Circ Physiol ; 324(6): H804-H820, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36961489

RESUMO

Right ventricular (RV) failure is the major determinant of outcome in pulmonary hypertension (PH). Calves exposed to 2-wk hypoxia develop severe PH and unlike rodents, hypoxia-induced PH in this species can lead to right heart failure. We, therefore, sought to examine the molecular and structural changes in the RV in calves with hypoxia-induced PH, hypothesizing that we could identify mechanisms underlying compensated physiological function in the face of developing severe PH. Calves were exposed to 14 days of environmental hypoxia (equivalent to 4,570 m/15,000 ft elevation, n = 29) or ambient normoxia (1,525 m/5,000 ft, n = 25). Cardiopulmonary function was evaluated by right heart catheterization and pressure volume loops. Molecular and cellular determinants of RV remodeling were analyzed by cDNA microarrays, RealTime PCR, proteomics, and immunochemistry. Hypoxic exposure induced robust PH, with increased RV contractile performance and preserved cardiac output, yet evidence of dysregulated RV-pulmonary artery mechanical coupling as seen in advanced disease. Analysis of gene expression revealed cellular processes associated with structural remodeling, cell signaling, and survival. We further identified specific clusters of gene expression associated with 1) hypertrophic gene expression and prosurvival mechanotransduction through YAP-TAZ signaling, 2) extracellular matrix (ECM) remodeling, 3) inflammatory cell activation, and 4) angiogenesis. A potential transcriptomic signature of cardiac fibroblasts in RV remodeling was detected, enriched in functions related to cell movement, tissue differentiation, and angiogenesis. Proteomic and immunohistochemical analysis confirmed RV myocyte hypertrophy, together with localization of ECM remodeling, inflammatory cell activation, and endothelial cell proliferation within the RV interstitium. In conclusion, hypoxia and hemodynamic load initiate coordinated processes of protective and compensatory RV remodeling to withstand the progression of PH.NEW & NOTEWORTHY Using a large animal model and employing a comprehensive approach integrating hemodynamic, transcriptomic, proteomic, and immunohistochemical analyses, we examined the early (2 wk) effects of severe PH on the RV. We observed that RV remodeling during PH progression represents a continuum of transcriptionally driven processes whereby cardiac myocytes, fibroblasts, endothelial cells, and proremodeling macrophages act to coordinately maintain physiological homeostasis and protect myocyte survival during chronic, severe, and progressive pressure overload.


Assuntos
Insuficiência Cardíaca , Hipertensão Pulmonar , Disfunção Ventricular Direita , Animais , Bovinos , Hipertensão Pulmonar/metabolismo , Células Endoteliais/metabolismo , Mecanotransdução Celular , Proteômica , Hipertrofia Ventricular Direita/genética , Hipertrofia Ventricular Direita/metabolismo , Ventrículos do Coração , Modelos Animais de Doenças , Hipóxia , Remodelação Ventricular , Função Ventricular Direita , Disfunção Ventricular Direita/genética , Disfunção Ventricular Direita/complicações
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