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1.
Genome Res ; 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39284687

RESUMO

The use of long-read direct RNA sequencing (DRS) and PCR cDNA sequencing (PCS) in clinical oncology remains limited, with no direct comparison between the two methods. We used DRS and PCS to study clear cell renal cell carcinoma (ccRCC), focussing on new transcript and gene discovery. Twelve primary ccRCC archival tumors, six from patients who went on to relapse, were analysed. Results were validated in an independent cohort of twenty patients by qRT-PCR and compared to DRS analysis of RCC4 cells. In archival clinical samples and due to long-term storage, average read length was lower (400-500nt) than that achieved through DRS of RCC4 cells (>1100nt). Still, deconvolution analysis showed a loss of immune infiltrate in primary tumors of patients who relapse as reported by others. Differentially expressed genes in patients who went on to relapse were determined with good overlap between DRS and PCS, identifying LINC04216 and the T cell exhaustion marker TOX as novel candidate recurrence-associated genes. Novel transcript analysis revealed over 10,000 candidate novel transcripts detected by both methods and in ccRCC cells in vitro, including a novel CD274 (PD-L1) transcript encoding for the soluble version of the protein with a longer 3' UTR and lower stability than the annotated transcript. Both methods identified 414 novel genes, also detected in RCC4 cells, including a novel noncoding gene over-expressed in patients who relapse. Overall, we showcase use of PCS and DRS in archival tumor samples to uncover unmapped features of cancer transcriptomes, linked to disease progression and immune evasion.

2.
J Mol Cell Cardiol ; 184: 75-87, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37805125

RESUMO

Caveolae are tiny invaginations in the sarcolemma that buffer extra membrane and contribute to mechanical regulation of cellular function. While the role of caveolae in membrane mechanosensation has been studied predominantly in non-cardiomyocyte cells, caveolae contribution to cardiac mechanotransduction remains elusive. Here, we studied the role of caveolae in the regulation of Ca2+ signaling in atrial cardiomyocytes. In Langendorff-perfused mouse hearts, atrial pressure/volume overload stretched atrial myocytes and decreased caveolae density. In isolated cells, caveolae were disrupted through hypotonic challenge that induced a temporal (<10 min) augmentation of Ca2+ transients and caused a rise in Ca2+ spark activity. Similar changes in Ca2+ signaling were observed after chemical (methyl-ß-cyclodextrin) and genetic ablation of caveolae in cardiac-specific conditional caveolin-3 knock-out mice. Acute disruption of caveolae, both mechanical and chemical, led to the elevation of cAMP level in the cell interior, and cAMP-mediated augmentation of protein kinase A (PKA)-phosphorylated ryanodine receptors (at Ser2030 and Ser2808). Caveolae-mediated stimulatory effects on Ca2+ signaling were abolished via inhibition of cAMP production by adenyl cyclase antagonists MDL12330 and SQ22536, or reduction of PKA activity by H-89. A compartmentalized mathematical model of mouse atrial myocytes linked the observed changes to a microdomain-specific decrease in phosphodiesterase activity, which disrupted cAMP signaling and augmented PKA activity. Our findings add a new dimension to cardiac mechanobiology and highlight caveolae-associated cAMP/PKA-mediated phosphorylation of Ca2+ handling proteins as a novel component of mechano-chemical feedback in atrial myocytes.


Assuntos
Fibrilação Atrial , Miócitos Cardíacos , Camundongos , Animais , Miócitos Cardíacos/metabolismo , Cavéolas/metabolismo , Mecanotransdução Celular , Fibrilação Atrial/metabolismo , AMP Cíclico/metabolismo , Transdução de Sinais/fisiologia
3.
Am J Physiol Endocrinol Metab ; 324(5): E437-E448, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37018654

RESUMO

We aimed to investigate the human skeletal muscle (SkM) DNA methylome after exercise in low-carbohydrate (CHO) energy-balance (with high-fat) conditions compared with exercise in low-CHO energy-deficit (with low-fat) conditions. The objective was to identify novel epigenetically regulated genes and pathways associated with "train-low sleep-low" paradigms. The sleep-low conditions included nine males that cycled to deplete muscle glycogen while reaching a set energy expenditure. Postexercise, low-CHO meals (protein matched) completely replaced (using high fat) or only partially replaced (low fat) the energy expended. The following morning, resting baseline biopsies were taken and the participants then undertook 75 minutes of cycling exercise, with skeletal muscle biopsies collected 30 minutes and 3.5 hours postexercise. Discovery of genome-wide DNA methylation was undertaken using Illumina EPIC arrays, and targeted gene expression analysis was conducted by quantitative RT-PCR. At baseline, participants under energy balance (high fat) demonstrated a predominantly hypermethylated (60%) profile across the genome compared to energy-deficit low-fat conditions. However, postexercise performed in energy balance (with high fat) elicited a more prominent hypomethylation signature 30 minutes postexercise in gene regulatory regions important for transcription (CpG islands within promoter regions) compared with exercise in energy-deficit (with low-fat) conditions. Such hypomethylation was enriched within pathways related to IL6-JAK-STAT signaling, metabolic processes, p53/cell cycle, and oxidative/fatty acid metabolism. Hypomethylation within the promoter regions of the genes; histone deacetylase 2 (HDAC2), MECR, IGF2, and c13orf16 were associated with significant increases in gene expression in the postexercise period in energy balance compared with an energy deficit. Furthermore, HDAC11 was oppositely regulated at the gene expression level compared with family member HDAC2, where HDAC11 was hypomethylated yet increased in energy-deficit compared with energy-balance conditions. Overall, we identify some novel epigenetically regulated genes associated with train-low sleep-low paradigms.NEW & NOTEWORTHY We identify novel epigenetically regulated genes associated with train-low sleep-low paradigms. Exercise under low-carbohydrate (CHO) energy-balance (high-fat) conditions elicited a more prominent DNA hypomethylation signature 30 minutes postexercise compared with low-CHO energy-deficit (low-fat) conditions. This was enriched within IL6-JAK-STAT signaling, metabolic processes, p53, cell cycle, oxidative phosphorylation, and fatty acid metabolism. Histone deacetylase (HDAC) family members 2, 4, 10, and 11 demonstrated hypomethylation, with HDAC2 and HDAC11 possessing alternative regulation of gene expression in energy balance versus deficit conditions.


Assuntos
Epigenoma , Interleucina-6 , Masculino , Humanos , Interleucina-6/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Músculo Esquelético/metabolismo , Glicogênio/metabolismo , Ácidos Graxos/metabolismo
4.
FASEB J ; 37(1): e22720, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36542473

RESUMO

Cancer survivors suffer impairments in skeletal muscle in terms of reduced mass and function. Interestingly, human skeletal muscle possesses an epigenetic memory of earlier stimuli, such as exercise. Long-term retention of epigenetic changes in skeletal muscle following cancer survival and/or exercise training has not yet been studied. We, therefore, investigated genome-wide DNA methylation (methylome) in skeletal muscle following a 5-month, 3/week aerobic-training intervention in breast cancer survivors 10-14 years after diagnosis and treatment. These results were compared to breast cancer survivors who remained untrained and to age-matched controls with no history of cancer, who undertook the same training intervention. Skeletal muscle biopsies were obtained from 23 females before(pre) and after(post) the 5-month training period. InfiniumEPIC 850K DNA methylation arrays and RT-PCR for gene expression were performed. The breast cancer survivors displayed a significant retention of increased DNA methylation (i.e., hypermethylation) at a larger number of differentially methylated positions (DMPs) compared with healthy age-matched controls pre training. Training in cancer survivors led to an exaggerated number of DMPs with a hypermethylated signature occurring at non-regulatory regions compared with training in healthy age-matched controls. However, the opposite occurred in important gene regulatory regions, where training in cancer survivors elicited a considerable reduction in methylation (i.e., hypomethylation) in 99% of the DMPs located in CpG islands within promoter regions. Importantly, training was able to reverse the hypermethylation identified in cancer survivors back toward a hypomethylated signature that was observed pre training in healthy age-matched controls at 300 (out of 881) of these island/promoter-associated CpGs. Pathway enrichment analysis identified training in cancer survivors evoked a predominantly hypomethylated signature in pathways associated with cell cycle, DNA replication/repair, transcription, translation, mTOR signaling, and the proteosome. Differentially methylated region (DMR) analysis also identified genes: BAG1, BTG2, CHP1, KIFC1, MKL2, MTR, PEX11B, POLD2, S100A6, SNORD104, and SPG7 as hypermethylated in breast cancer survivors, with training reversing these CpG island/promoter-associated DMRs toward a hypomethylated signature. Training also elicited a largely different epigenetic response in healthy individuals than that observed in cancer survivors, with very few overlapping changes. Only one gene, SIRT2, was identified as having altered methylation in cancer survivors at baseline and after training in both the cancer survivors and healthy controls. Overall, human skeletal muscle may retain a hypermethylated signature as long as 10-14 years after breast cancer treatment/survival. Five months of aerobic training reset the skeletal muscle methylome toward signatures identified in healthy age-matched individuals in gene regulatory regions.


Assuntos
Neoplasias da Mama , Proteínas Imediatamente Precoces , Feminino , Humanos , Epigenoma , Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Metilação de DNA , Epigênese Genética , Exercício Físico/fisiologia , Músculo Esquelético/fisiologia , Ilhas de CpG/genética , Proteínas Imediatamente Precoces/genética , Proteínas Supressoras de Tumor/genética
5.
J Behav Addict ; 11(2): 222-225, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35895459

RESUMO

This paper comments three recent publications in the Journal of Behavioral Addictions (Brand et al., 2022; Gola et al., 2022; Sassover & Weinstein, 2022). It shortly discusses (1) the role of researcher biases and the significance of the naming of a disorder (here "sexual addiction" and "pornography use disorder") for stigma and treatment, (2) the development and course of CSBD and its significance for research results, (3) the role of "Sexual" in CSBD. The paper concludes that the guidelines for CSBD give a precise description and the authors plea for an exchange between disciplines and a sex positive treatment approach.


Assuntos
Transtornos Parafílicos , Disfunções Sexuais Psicogênicas , Comportamento Compulsivo , Literatura Erótica , Humanos , Comportamento Sexual , Disfunções Sexuais Psicogênicas/terapia
6.
Nat Biotechnol ; 40(10): 1488-1499, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35637420

RESUMO

High-order three-dimensional (3D) interactions between more than two genomic loci are common in human chromatin, but their role in gene regulation is unclear. Previous high-order 3D chromatin assays either measure distant interactions across the genome or proximal interactions at selected targets. To address this gap, we developed Pore-C, which combines chromatin conformation capture with nanopore sequencing of concatemers to profile proximal high-order chromatin contacts at the genome scale. We also developed the statistical method Chromunity to identify sets of genomic loci with frequencies of high-order contacts significantly higher than background ('synergies'). Applying these methods to human cell lines, we found that synergies were enriched in enhancers and promoters in active chromatin and in highly transcribed and lineage-defining genes. In prostate cancer cells, these included binding sites of androgen-driven transcription factors and the promoters of androgen-regulated genes. Concatemers of high-order contacts in highly expressed genes were demethylated relative to pairwise contacts at the same loci. Synergies in breast cancer cells were associated with tyfonas, a class of complex DNA amplicons. These results rigorously link genome-wide high-order 3D interactions to lineage-defining transcriptional programs and establish Pore-C and Chromunity as scalable approaches to assess high-order genome structure.


Assuntos
Sequenciamento por Nanoporos , Nanoporos , Androgênios , Cromatina/genética , Humanos , Fatores de Transcrição/genética
7.
Front Hum Neurosci ; 16: 705238, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35250509

RESUMO

Surgical expertise does not have a clear definition and is often culturally associated with power, authority, prestige, and case number rather than more objective proxies of excellence. Multiple models of expertise progression have been proposed including the Dreyfus model, however, they all currently require subjective evaluation of skill. Recently, efforts have been made to improve the ways in which surgical excellence is measured and expertise is defined using artificial intelligence, video recordings, and accelerometers. However, these aforementioned methods of assessment are still subjective or indirect proxies of expertise, thus uncovering the neural mechanisms that differentiate expert surgeons from trainees may enhance the objectivity of surgical expertise validation. In fact, some researchers have already suggested that their neural imaging-based expertise classification methods outperform currently used methods of surgical skill certification such as the Fundamentals of Laparoscopic Surgery (FLS) scores. Such imaging biomarkers would not only help better identify the highest performing surgeons, but could also improve residency programs by providing more objective, evidence-based feedback and developmental milestones for those in training and perhaps act as a marker of surgical potential in medical students. Despite the potential advantages of using neural imaging in the assessment of surgical expertise, this field of research remains in its infancy. This systematic review identifies studies that have applied neuromonitoring in assessing surgical skill across levels of expertise. The goals of this review are to identify (1) the strongest neural indicators of surgical expertise, (2) the limitations of the current literature on this subject, (3) the most sensible future directions for further study. We found substantial evidence that surgical expertise can be delineated by differential activation and connectivity in the prefrontal cortex (PFC) across multiple task and neuroimaging modalities. Specifically, novices tend to have greater PFC activation than experts under standard conditions in bimanual and decision-making tasks. However, under high temporal demand tasks, experts had increased PFC activation whereas novices had decreased PFC activation. Common limitations uncovered in this review were that task difficulty was often insufficient to delineate between residents and attending. Moreover, attending level involvement was also low in multiple studies which may also have contributed to this issue. Most studies did not analyze the ability of their neuromonitoring findings to accurately classify subjects by level of expertise. Finally, the predominance of fNIRS as the neuromonitoring modality limits our ability to uncover the neural correlates of surgical expertise in non-cortical brain regions. Future studies should first strive to address these limitations. In the longer term, longitudinal within-subjects design over the course of a residency or even a career will also advance the field. Although logistically arduous, such studies would likely be most beneficial in demonstrating effects of increasing surgical expertise on regional brain activation and inter-region connectivity.

8.
Cardiol Young ; 32(12): 1952-1956, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35152927

RESUMO

BACKGROUND: Recurrent laryngeal nerve injury leading to vocal cord paralysis is a known complication of cardiothoracic surgery. Its occurrence during interventional catheterisation procedures has been documented in case reports, but there have been no studies to determine an incidence. OBJECTIVE: To establish the incidence of left recurrent laryngeal nerve injury leading to vocal cord paralysis after left pulmonary artery stenting, patent ductus arteriosus device closure and the combination of the procedures either consecutively or simultaneously. METHODS: Members of the Congenital Cardiovascular Interventional Study Consortium were asked to perform a retrospective analysis to identify cases of recurrent laryngeal nerve injury after the aforementioned procedures. Twelve institutions participated in the analysis. They also contributed the total number of each procedure performed at their respective institutions for statistical purposes. RESULTS: Of the 1337 patients who underwent left pulmonary artery stent placement, six patients (0.45%) had confirmed vocal cord paralysis. 4001 patients underwent patent ductus arteriosus device closure, and two patients (0.05%) developed left vocal cord paralysis. Patients who underwent both left pulmonary artery stent placement and patent ductus arteriosus device closure had the highest incidence of vocal cord paralysis which occurred in 4 of the 26 patients (15.4%). Overall, 92% of affected patients in our study population had resolution of symptoms. CONCLUSION: Recurrent laryngeal nerve injury is a rare complication of left pulmonary artery stent placement or patent ductus arteriosus device closure. However, the incidence is highest in patients undergoing both procedures either consecutively or simultaneously. Additional research is necessary to determine contributing factors that might reduce the risk of recurrent laryngeal nerve injury.


Assuntos
Permeabilidade do Canal Arterial , Traumatismos do Nervo Laríngeo Recorrente , Paralisia das Pregas Vocais , Humanos , Traumatismos do Nervo Laríngeo Recorrente/etiologia , Traumatismos do Nervo Laríngeo Recorrente/complicações , Paralisia das Pregas Vocais/epidemiologia , Paralisia das Pregas Vocais/etiologia , Permeabilidade do Canal Arterial/epidemiologia , Permeabilidade do Canal Arterial/cirurgia , Permeabilidade do Canal Arterial/complicações , Incidência , Estudos Retrospectivos , Cateterismo/efeitos adversos
9.
Genome Biol ; 22(1): 227, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34482832

RESUMO

We develop the Oncogene Concatenated Enriched Amplicon Nanopore Sequencing (OCEANS) method, in which variants with low variant allele frequency (VAFs) are amplified and subsequently concatenated for Nanopore Sequencing. OCEANS allows accurate detection of somatic mutations with VAF limits of detection between 0.05 and 1%. We construct 4 distinct multi-gene OCEANS panels targeting recurrent mutations in acute myeloid leukemia, melanoma, non-small- cell lung cancer, and hepatocellular carcinoma and validate them on clinical samples. By demonstrating detection of low VAF single nucleotide variant mutations using Nanopore Sequencing, OCEANS is poised to enable same-day clinical sequencing panels.


Assuntos
Mutação , Sequenciamento por Nanoporos/métodos , Neoplasias/genética , Oncogenes/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Leucemia Mieloide Aguda/genética , Neoplasias Pulmonares/genética , Melanoma
10.
A A Pract ; 15(4): e01432, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33783367

RESUMO

The role of concurrent illness in coronavirus disease 2019 (COVID-19) is unknown. Patients with leukemia may display altered thromboinflammatory responses. We report a 53-year-old man presenting with acute leukemia and COVID-19 who developed thrombotic complications and acute respiratory distress syndrome. Multiple analyses, including rotational thromboelastometry and flow cytometry on blood and bronchoalveolar lavage, are reported to characterize coagulation and immune profiles. The patient developed chemotherapy-induced neutropenia that may have protected his lungs from granulocyte-driven hyperinflammatory acute lung injury. However, neutropenia also alters viral clearing, potentially enabling ongoing viral propagation. This case depicts a precarious equilibrium between leukemia and COVID-19.


Assuntos
Lesão Pulmonar Aguda/complicações , Transtornos da Coagulação Sanguínea/complicações , Transtornos da Coagulação Sanguínea/patologia , COVID-19/complicações , COVID-19/patologia , Leucemia Mieloide Aguda/complicações , Lesão Pulmonar Aguda/diagnóstico , Lesão Pulmonar Aguda/patologia , Transtornos da Coagulação Sanguínea/diagnóstico , Lavagem Broncoalveolar , COVID-19/diagnóstico , Citometria de Fluxo , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Neutropenia/complicações , Neutropenia/diagnóstico , Neutropenia/patologia , SARS-CoV-2 , Tromboelastografia , Fatores de Virulência
11.
Am J Physiol Cell Physiol ; 320(1): C45-C56, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33052072

RESUMO

UBR5 is an E3 ubiquitin ligase positively associated with anabolism, hypertrophy, and recovery from atrophy in skeletal muscle. The precise mechanisms underpinning UBR5's role in the regulation of skeletal muscle mass remain unknown. The present study aimed to elucidate these mechanisms by silencing the UBR5 gene in vivo. To achieve this aim, we electroporated a UBR5-RNAi plasmid into mouse tibialis anterior muscle to investigate the impact of reduced UBR5 on anabolic signaling MEK/ERK/p90RSK and Akt/GSK3ß/p70S6K/4E-BP1/rpS6 pathways. Seven days after UBR5 RNAi electroporation, although reductions in overall muscle mass were not detected, the mean cross-sectional area (CSA) of green fluorescent protein (GFP)-positive fibers were reduced (-9.5%) and the number of large fibers were lower versus the control. Importantly, UBR5-RNAi significantly reduced total RNA, muscle protein synthesis, ERK1/2, Akt, and GSK3ß activity. Although p90RSK phosphorylation significantly increased, total p90RSK protein levels demonstrated a 45% reduction with UBR5-RNAi. Finally, these early events after 7 days of UBR5 knockdown culminated in significant reductions in muscle mass (-4.6%) and larger reductions in fiber CSA (-18.5%) after 30 days. This was associated with increased levels of phosphatase PP2Ac and inappropriate chronic elevation of p70S6K and rpS6 between 7 and 30 days, as well as corresponding reductions in eIF4e. This study demonstrates that UBR5 plays an important role in anabolism/hypertrophy, whereby knockdown of UBR5 culminates in skeletal muscle atrophy.


Assuntos
Metabolismo Energético , Músculo Esquelético/enzimologia , Atrofia Muscular/enzimologia , Ubiquitina-Proteína Ligases/metabolismo , Animais , Regulação para Baixo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Técnicas de Silenciamento de Genes , Glicogênio Sintase Quinase 3 beta/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Músculo Esquelético/patologia , Atrofia Muscular/genética , Atrofia Muscular/patologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Transdução de Sinais , Fatores de Tempo , Ubiquitina-Proteína Ligases/deficiência , Ubiquitina-Proteína Ligases/genética
12.
Int J Mol Sci ; 21(21)2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33113898

RESUMO

Following cell stress such as ionising radiation (IR) exposure, multiple cellular pathways are activated. We recently demonstrated that ferredoxin reductase (FDXR) has a remarkable IR-induced transcriptional responsiveness in blood. Here, we provided a first comprehensive FDXR variant profile following DNA damage. First, specific quantitative real-time polymerase chain reaction (qPCR) primers were designed to establish dose-responses for eight curated FDXR variants, all up-regulated after IR in a dose-dependent manner. The potential role of gender on the expression of these variants was tested, and neither the variants response to IR nor the background level of expression was profoundly affected; moreover, in vitro induction of inflammation temporarily counteracted IR response early after exposure. Importantly, transcriptional up-regulation of these variants was further confirmed in vivo in blood of radiotherapy patients. Full-length nanopore sequencing was performed to identify other FDXR variants and revealed the high responsiveness of FDXR-201 and FDXR-208. Moreover, FDXR-218 and FDXR-219 showed no detectable endogenous expression, but a clear detection after IR. Overall, we characterised 14 FDXR transcript variants and identified for the first time their response to DNA damage in vivo. Future studies are required to unravel the function of these splicing variants, but they already represent a new class of radiation exposure biomarkers.


Assuntos
Sangue/efeitos da radiação , Neoplasias/genética , Oxirredutases/genética , Regulação para Cima , Adulto , Processamento Alternativo , Dano ao DNA , Relação Dose-Resposta à Radiação , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/radioterapia , Radiação Ionizante
13.
J Biol Chem ; 295(19): 6498-6508, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32238431

RESUMO

Arrestin-1 is the arrestin family member responsible for inactivation of the G protein-coupled receptor rhodopsin in photoreceptors. Arrestin-1 is also well-known to interact with additional protein partners and to affect other signaling cascades beyond phototransduction. In this study, we investigated one of these alternative arrestin-1 binding partners, the glycolysis enzyme enolase-1, to map the molecular contact sites between these two proteins and investigate how the binding of arrestin-1 affects the catalytic activity of enolase-1. Using fluorescence quench protection of strategically placed fluorophores on the arrestin-1 surface, we observed that arrestin-1 primarily engages enolase-1 along a surface that is opposite of the side of arrestin-1 that binds photoactivated rhodopsin. Using this information, we developed a molecular model of the arrestin-1-enolase-1 complex, which was validated by targeted substitutions of charge-pair interactions. Finally, we identified the likely source of arrestin's modulation of enolase-1 catalysis, showing that selective substitution of two amino acids in arrestin-1 can completely remove its effect on enolase-1 activity while still remaining bound to enolase-1. These findings open up opportunities for examining the functional effects of arrestin-1 on enolase-1 activity in photoreceptors and their surrounding cells.


Assuntos
Arrestina/química , Biomarcadores Tumorais/química , Proteínas de Ligação a DNA/química , Modelos Moleculares , Complexos Multienzimáticos/química , Fosfopiruvato Hidratase/química , Rodopsina/química , Proteínas Supressoras de Tumor/química , Arrestina/genética , Sítios de Ligação , Biomarcadores Tumorais/genética , Catálise , Proteínas de Ligação a DNA/genética , Humanos , Complexos Multienzimáticos/genética , Fosfopiruvato Hidratase/genética , Rodopsina/genética , Proteínas Supressoras de Tumor/genética
14.
Br J Haematol ; 189(5): e211-e213, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32236943
15.
Radiat Res ; 193(2): 143-154, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31829904

RESUMO

In the event of a large-scale event leading to acute ionizing radiation exposure, high-throughput methods would be required to assess individual dose estimates for triage purposes. Blood-based gene expression is a broad source of biomarkers of radiation exposure which have great potential for providing rapid dose estimates for a large population. Time is a crucial component in radiological emergencies and the shipment of blood samples to relevant laboratories presents a concern. In this study, we performed nanopore sequencing analysis to determine if the technology can be used to detect radiation-inducible genes in human peripheral blood mononuclear cells (PBMCs). The technology offers not only long-read sequencing but also a portable device which can overcome issues involving sample shipment, and provide faster results. For this goal, blood from nine healthy volunteers was 2 Gy ex vivo X irradiated. After PBMC isolation, irradiated samples were incubated along with the controls for 24 h at 37°C. RNA was extracted, poly(A)+ enriched and reverse-transcribed before sequencing. The data generated was analyzed using a Snakemake pipeline modified to handle paired samples. The sequencing analysis identified a radiation signature consisting of 46 differentially expressed genes (DEGs) which included 41 protein-coding genes, a long non-coding RNA and four pseudogenes, five of which have been identified as radiation-responsive transcripts for the first time. The genes in which transcriptional expression is most significantly modified after radiation exposure were APOBEC3H and FDXR, presenting a 25- and 28-fold change on average, respectively. These levels of transcriptional response were comparable to results we obtained by quantitative polymerase chain reaction (qPCR) analysis. In vivo exposure analyses showed a transcriptional radioresponse at 24 h postirradiation for both genes together with a strong dose-dependent response in blood irradiated ex vivo. Finally, extrapolating from the data we obtained, the minimum sequencing time required to detect an irradiated sample using APOBEC3H transcripts would be less than 3 min for a total of 50,000 reads. Future improvements, in sample processing and bioinformatic pipeline for specific radiation-responsive transcript identification, will allow the provision of a portable, rapid, real-time biodosimetry platform based on this new sequencing technology. In summary, our data show that nanopore sequencing can identify radiation-responsive genes and can also be used for identification of new transcripts.


Assuntos
Sangue/metabolismo , Sangue/efeitos da radiação , Sequenciamento por Nanoporos , Exposição à Radiação/efeitos adversos , Transcrição Gênica/efeitos da radiação , Transcriptoma/efeitos da radiação , Relação Dose-Resposta à Radiação , Genômica , Humanos , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/efeitos da radiação
16.
ISME J ; 14(3): 727-739, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31822788

RESUMO

Acanthamoeba-infecting Mimiviridae are giant viruses with dsDNA genome up to 1.5 Mb. They build viral factories in the host cytoplasm in which the nuclear-like virus-encoded functions take place. They are themselves the target of infections by 20-kb-dsDNA virophages, replicating in the giant virus factories and can also be found associated with 7-kb-DNA episomes, dubbed transpovirons. Here we isolated a virophage (Zamilon vitis) and two transpovirons respectively associated to B- and C-clade mimiviruses. We found that the virophage could transfer each transpoviron provided the host viruses were devoid of a resident transpoviron (permissive effect). If not, only the resident transpoviron originally isolated from the corresponding virus was replicated and propagated within the virophage progeny (dominance effect). Although B- and C-clade viruses devoid of transpoviron could replicate each transpoviron, they did it with a lower efficiency across clades, suggesting an ongoing process of adaptive co-evolution. We analysed the proteomes of host viruses and virophage particles in search of proteins involved in this adaptation process. This study also highlights a unique example of intricate commensalism in the viral world, where the transpoviron uses the virophage to propagate and where the Zamilon virophage and the transpoviron depend on the giant virus to replicate, without affecting its infectious cycle.


Assuntos
Acanthamoeba/virologia , Mimiviridae/fisiologia , Vírus Gigantes/genética , Vírus Gigantes/fisiologia , Mimiviridae/genética , Mimiviridae/crescimento & desenvolvimento , Mimiviridae/isolamento & purificação , Simbiose , Virófagos/genética , Virófagos/fisiologia
17.
World J Pediatr Congenit Heart Surg ; 11(4): NP229-NP231, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-30983537

RESUMO

During initial repair of supracardiac total anomalous pulmonary venous connection (TAPVC), the vertical vein (VV) is sometimes left patent (not ligated or divided) in the hope that this strategy may reduce the likelihood or severity of postoperative pulmonary hypertensive crises. We report a case of a 35-year-old pregnant patient with previously repaired supracardiac TAPVC who presented with atrial arrhythmia and right heart dilation. A cardiac magnetic resonance imaging study confirmed the diagnosis of patency of the vertical vein and right heart dilation. The VV was occluded with a catheter-delivered vascular occlusion device through a percutaneous approach, resulting in resolution of right heart dilation and arrhythmia. This case highlights the role of cross-sectional imaging as an adjunct to echocardiography in adults with repaired congenital heart disease.


Assuntos
Complicações Cardiovasculares na Gravidez , Veias Pulmonares/anormalidades , Síndrome de Cimitarra/cirurgia , Procedimentos Cirúrgicos Vasculares/métodos , Adulto , Ecocardiografia , Feminino , Humanos , Imagem Cinética por Ressonância Magnética/métodos , Período Pós-Operatório , Gravidez , Veias Pulmonares/diagnóstico por imagem , Veias Pulmonares/cirurgia , Síndrome de Cimitarra/diagnóstico
18.
Catheter Cardiovasc Interv ; 94(4): 607-617, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31419019

RESUMO

OBJECTIVES: To investigate whether age and valve size at implant contribute to outcomes after Melody transcatheter pulmonary valve replacement (TPVR). BACKGROUND: Patient age and valve size at implant contribute to longevity of surgical pulmonary valves. METHODS: All patients discharged with a Melody valve in the pulmonary position, as part of three prospective Melody valve multicenter studies, comprised the study cohort. Acute and time-related outcomes were analyzed according to age: children (≤12 years), adolescents (13-18 years), young adults (19-29 years), and older adults (≥30 years). RESULTS: Successful Melody valve implantation occurred in 49 children, 107 adolescents, 96 young adults, and 57 older adults. Pediatric patients (≤18 years) were more likely to have TPVR for conduit stenosis than adults (62% vs. 44%); children had the smallest conduits. After TPVR, pediatric and adult patients had similar decreases in right ventricular (RV) size by MRI, but adults had improved percentage predicted peak VO2 (58% preimplant to 64% postimplant, p = .02) and FEV1 (69% pre to 71% post, p = .005). Younger age was associated with shorter freedom from RVOT dysfunction, reintervention, and explant. Children had the shortest freedom from endocarditis (p = .041), but all other groups had 5-year freedom from endocarditis of ≥90%. CONCLUSIONS: Younger age was associated with shorter time to RVOT dysfunction, reintervention, and explant after Melody TPVR. Patients ≥13 years of age were at low risk for endocarditis and explant to 5 years. A better understanding of time-related outcomes by age will aid in the comparison of therapeutic options for TPVR candidates. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT00740870 (NCT00740870), https://clinicaltrials.gov/ct2/show/NCT01186692 (NCT01186692), and https://clinicaltrials.gov/ct2/show/NCT00688571 (NCT00688571).


Assuntos
Cateterismo Cardíaco/instrumentação , Implante de Prótese de Valva Cardíaca/instrumentação , Próteses Valvulares Cardíacas , Valva Pulmonar/cirurgia , Adolescente , Fatores Etários , Canadá , Cateterismo Cardíaco/efeitos adversos , Criança , Ensaios Clínicos como Assunto , Bases de Dados Factuais , Remoção de Dispositivo , Endocardite/etiologia , Endocardite/fisiopatologia , Endocardite/cirurgia , Europa (Continente) , Feminino , Implante de Prótese de Valva Cardíaca/efeitos adversos , Hemodinâmica , Humanos , Masculino , Intervalo Livre de Progressão , Desenho de Prótese , Falha de Prótese , Valva Pulmonar/diagnóstico por imagem , Valva Pulmonar/fisiopatologia , Reoperação , Fatores de Risco , Fatores de Tempo , Estados Unidos , Obstrução do Fluxo Ventricular Externo/etiologia , Obstrução do Fluxo Ventricular Externo/fisiopatologia , Obstrução do Fluxo Ventricular Externo/cirurgia , Adulto Jovem
19.
Ann Pediatr Cardiol ; 12(2): 159-162, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31143047

RESUMO

AMPLATZER™ muscular ventricular septal defect occluder is used commonly for off-label purposes. We describe an unusual case of a patient with tetralogy of Fallot who underwent repair with a right ventricle to pulmonary artery homograft due to abnormal coronary artery pattern. During the initial surgery, the native right ventricular outflow tract was left open. At 30 years of age, he was symptomatic due to severe native right ventricular outflow tract insufficiency. Cardiac MRI confirmed a dilated right ventricle and pulmonary insufficiency through the native right ventricular outflow tract, despite no significant homograft insufficiency due to previous Melody® valve placement. The right ventricular outflow tract was closed successfully using an 18 mm AMPLATZER™ muscular ventricular septal defect occluder. At 5-year follow-up, there is no native right ventricular outflow tract insufficiency and no additional arrhythmia. We suggest that percutaneous closure of the insufficient; native right ventricular outflow tract using a septal occluder is an alternative to surgical management.

20.
Sci Rep ; 9(1): 4251, 2019 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-30862794

RESUMO

Transcriptome wide changes in human skeletal muscle after acute (anabolic) and chronic resistance exercise (RE) induced hypertrophy have been extensively determined in the literature. We have also recently undertaken DNA methylome analysis (850,000 + CpG sites) in human skeletal muscle after acute and chronic RE, detraining and retraining, where we identified an association between DNA methylation and epigenetic memory of exercise induced skeletal muscle hypertrophy. However, it is currently unknown as to whether all the genes identified in the transcriptome studies to date are also epigenetically regulated at the DNA level after acute, chronic or repeated RE exposure. We therefore aimed to undertake large scale bioinformatical analysis by pooling the publicly available transcriptome data after acute (110 samples) and chronic RE (181 samples) and comparing these large data sets with our genome-wide DNA methylation analysis in human skeletal muscle after acute and chronic RE, detraining and retraining. Indeed, after acute RE we identified 866 up- and 936 down-regulated genes at the expression level, with 270 (out of the 866 up-regulated) identified as being hypomethylated, and 216 (out of 936 downregulated) as hypermethylated. After chronic RE we identified 2,018 up- and 430 down-regulated genes with 592 (out of 2,018 upregulated) identified as being hypomethylated and 98 (out of 430 genes downregulated) as hypermethylated. After KEGG pathway analysis, genes associated with 'cancer' pathways were significantly enriched in both bioinformatic analysis of the pooled transcriptome and methylome datasets after both acute and chronic RE. This resulted in 23 (out of 69) and 28 (out of 49) upregulated and hypomethylated and 12 (out of 37) and 2 (out of 4) downregulated and hypermethylated 'cancer' genes following acute and chronic RE respectively. Within skeletal muscle tissue, these 'cancer' genes predominant functions were associated with matrix/actin structure and remodelling, mechano-transduction (e.g. PTK2/Focal Adhesion Kinase and Phospholipase D- following chronic RE), TGF-beta signalling and protein synthesis (e.g. GSK3B after acute RE). Interestingly, 51 genes were also identified to be up/downregulated in both the acute and chronic RE pooled transcriptome analysis as well as significantly hypo/hypermethylated after acute RE, chronic RE, detraining and retraining. Five genes; FLNB, MYH9, SRGAP1, SRGN, ZMIZ1 demonstrated increased gene expression in the acute and chronic RE transcriptome and also demonstrated hypomethylation in these conditions. Importantly, these 5 genes demonstrated retained hypomethylation even during detraining (following training induced hypertrophy) when exercise was ceased and lean mass returned to baseline (pre-training) levels, identifying them as genes associated with epigenetic memory in skeletal muscle. Importantly, for the first time across the transcriptome and epigenome combined, this study identifies novel differentially methylated genes associated with human skeletal muscle anabolism, hypertrophy and epigenetic memory.


Assuntos
Metilação de DNA/fisiologia , Exercício Físico/fisiologia , Proteínas Musculares/metabolismo , Músculo Esquelético/fisiologia , Treinamento Resistido , Transcriptoma/fisiologia , Conjuntos de Dados como Assunto , Regulação para Baixo/fisiologia , Epigênese Genética/fisiologia , Perfilação da Expressão Gênica , Humanos , Hipertrofia/fisiopatologia , Masculino , Proteínas Musculares/genética , Regulação para Cima/fisiologia , Adulto Jovem
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