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1.
Cell ; 167(7): 1681-1692, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27984720

RESUMO

The elucidation of the genetic code remains among the most influential discoveries in biology. While innumerable studies have validated the general universality of the code and its value in predicting and analyzing protein coding sequences, established and emerging work has also suggested that full genome decryption may benefit from a greater consideration of a codon's neighborhood within an mRNA than has been broadly applied. This Review examines the evidence for context cues in translation, with a focus on several recent studies that reveal broad roles for mRNA context in programming translation start sites, the rate of translation elongation, and stop codon identity.


Assuntos
Códon , Eucariotos/fisiologia , Biossíntese de Proteínas , RNA Mensageiro/química , Ribossomos/fisiologia , Imagem Molecular , Células Procarióticas/fisiologia , RNA Mensageiro/fisiologia , RNA de Transferência/fisiologia
2.
Annu Rev Genet ; 56: 89-112, 2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-35878627

RESUMO

Gametogenesis is a conserved developmental program whereby a diploid progenitor cell differentiates into haploid gametes, the precursors for sexually reproducing organisms. In addition to ploidy reduction and extensive organelle remodeling, gametogenesis naturally rejuvenates the ensuing gametes, leading to resetting of life span. Excitingly, ectopic expression of the gametogenesis-specific transcription factor Ndt80 is sufficient to extend life span in mitotically dividing budding yeast, suggesting that meiotic rejuvenation pathways can be repurposed outside of their natural context. In this review, we highlight recent studies of gametogenesis that provide emerging insight into natural quality control, organelle remodeling, and rejuvenation strategies that exist within a cell. These include selective inheritance, programmed degradation, and de novo synthesis, all of which are governed by the meiotic gene expression program entailing many forms of noncanonical gene regulation. Finally, we highlight critical questions that remain in the field and provide perspective on the implications of gametogenesis research on human health span.


Assuntos
Gametogênese , Rejuvenescimento , Humanos , Gametogênese/genética , Senescência Celular , Controle de Qualidade , Haploidia
3.
Cell ; 154(2): 442-51, 2013 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-23849981

RESUMO

The genetic interrogation and reprogramming of cells requires methods for robust and precise targeting of genes for expression or repression. The CRISPR-associated catalytically inactive dCas9 protein offers a general platform for RNA-guided DNA targeting. Here, we show that fusion of dCas9 to effector domains with distinct regulatory functions enables stable and efficient transcriptional repression or activation in human and yeast cells, with the site of delivery determined solely by a coexpressed short guide (sg)RNA. Coupling of dCas9 to a transcriptional repressor domain can robustly silence expression of multiple endogenous genes. RNA-seq analysis indicates that CRISPR interference (CRISPRi)-mediated transcriptional repression is highly specific. Our results establish that the CRISPR system can be used as a modular and flexible DNA-binding platform for the recruitment of proteins to a target DNA sequence, revealing the potential of CRISPRi as a general tool for the precise regulation of gene expression in eukaryotic cells.


Assuntos
Proteínas de Bactérias/genética , Marcação de Genes/métodos , Streptococcus pyogenes , Células HEK293 , Células HeLa , Humanos , Saccharomyces cerevisiae/genética , Pequeno RNA não Traduzido
4.
Nat Rev Mol Cell Biol ; 16(11): 651-64, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26465719

RESUMO

Ribosome profiling, which involves the deep sequencing of ribosome-protected mRNA fragments, is a powerful tool for globally monitoring translation in vivo. The method has facilitated discovery of the regulation of gene expression underlying diverse and complex biological processes, of important aspects of the mechanism of protein synthesis, and even of new proteins, by providing a systematic approach for experimental annotation of coding regions. Here, we introduce the methodology of ribosome profiling and discuss examples in which this approach has been a key factor in guiding biological discovery, including its prominent role in identifying thousands of novel translated short open reading frames and alternative translation products.


Assuntos
Biossíntese de Proteínas/genética , RNA Mensageiro/genética , Ribossomos/genética , Sequência de Bases , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Proteínas/metabolismo , Análise de Sequência de RNA
5.
J Mol Cell Cardiol ; 186: 31-44, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37979443

RESUMO

Ischemia/reperfusion (I/R) injury after revascularization contributes ∼50% of infarct size and causes heart failure, for which no established clinical treatment exists. ß-hydroxybutyrate (ß-OHB), which serves as both an energy source and a signaling molecule, has recently been reported to be cardioprotective when administered immediately before I/R and continuously after reperfusion. This study aims to determine whether administering ß-OHB at the time of reperfusion with a single dose can alleviate I/R injury and, if so, to define the mechanisms involved. We found plasma ß-OHB levels were elevated during ischemia in STEMI patients, albeit not to myocardial protection level, and decreased after revascularization. In mice, compared with normal saline, ß-OHB administrated at reperfusion reduced infarct size (by 50%) and preserved cardiac function, as well as activated autophagy and preserved mtDNA levels in the border zone. Our treatment with one dose ß-OHB reached a level achievable with fasting and strenuous physical activity. In neonatal rat ventricular myocytes (NRVMs) subjected to I/R, ß-OHB at physiologic level reduced cell death, increased autophagy, preserved mitochondrial mass, function, and membrane potential, in addition to attenuating reactive oxygen species (ROS) levels. ATG7 knockdown/knockout abolished the protective effects of ß-OHB observed both in vitro and in vivo. Mechanistically, ß-OHB's cardioprotective effects were associated with inhibition of mTOR signaling. In conclusion, ß-OHB, when administered at reperfusion, reduces infarct size and maintains mitochondrial homeostasis by increasing autophagic flux (potentially through mTOR inhibition). Since ß-OHB has been safely tested in heart failure patients, it may be a viable therapeutic to reduce infarct size in STEMI patients.


Assuntos
Insuficiência Cardíaca , Traumatismo por Reperfusão Miocárdica , Infarto do Miocárdio com Supradesnível do Segmento ST , Camundongos , Ratos , Animais , Humanos , Masculino , Ácido 3-Hidroxibutírico/farmacologia , Ácido 3-Hidroxibutírico/metabolismo , Ácido 3-Hidroxibutírico/uso terapêutico , Infarto do Miocárdio com Supradesnível do Segmento ST/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Mitocôndrias/metabolismo , Autofagia , Serina-Treonina Quinases TOR/metabolismo , Reperfusão , Insuficiência Cardíaca/metabolismo
6.
Diabetologia ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780786

RESUMO

AIMS/HYPOTHESIS: Our study aims to uncover glycaemic phenotype heterogeneity in type 1 diabetes. METHODS: In the Study of the French-speaking Society of Type 1 Diabetes (SFDT1), we characterised glycaemic heterogeneity thanks to a set of complementary metrics: HbA1c, time in range (TIR), time below range (TBR), CV, Gold score and glycaemia risk index (GRI). Applying the Discriminative Dimensionality Reduction with Trees (DDRTree) algorithm, we created a phenotypic tree, i.e. a 2D visual mapping. We also carried out a clustering analysis for comparison. RESULTS: We included 618 participants with type 1 diabetes (52.9% men, mean age 40.6 years [SD 14.1]). Our phenotypic tree identified seven glycaemic phenotypes. The 2D phenotypic tree comprised a main branch in the proximal region and glycaemic phenotypes in the distal areas. Dimension 1, the horizontal dimension, was positively associated with GRI (coefficient [95% CI]) (0.54 [0.52, 0.57]), HbA1c (0.39 [0.35, 0.42]), CV (0.24 [0.19, 0.28]) and TBR (0.11 [0.06, 0.15]), and negatively with TIR (-0.52 [-0.54, -0.49]). The vertical dimension was positively associated with TBR (0.41 [0.38, 0.44]), CV (0.40 [0.37, 0.43]), TIR (0.16 [0.12, 0.20]), Gold score (0.10 [0.06, 0.15]) and GRI (0.06 [0.02, 0.11]), and negatively with HbA1c (-0.21 [-0.25, -0.17]). Notably, socioeconomic factors, cardiovascular risk indicators, retinopathy and treatment strategy were significant determinants of glycaemic phenotype diversity. The phenotypic tree enabled more granularity than traditional clustering in revealing clinically relevant subgroups of people with type 1 diabetes. CONCLUSIONS/INTERPRETATION: Our study advances the current understanding of the complex glycaemic profile in people with type 1 diabetes and suggests that strategies based on isolated glycaemic metrics might not capture the complexity of the glycaemic phenotypes in real life. Relying on these phenotypes could improve patient stratification in type 1 diabetes care and personalise disease management.

7.
EMBO J ; 39(13): e104073, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32432379

RESUMO

Respirometry is the gold standard measurement of mitochondrial oxidative function, as it reflects the activity of the electron transport chain complexes working together. However, the requirement for freshly isolated mitochondria hinders the feasibility of respirometry in multi-site clinical studies and retrospective studies. Here, we describe a novel respirometry approach suited for frozen samples by restoring electron transfer components lost during freeze/thaw and correcting for variable permeabilization of mitochondrial membranes. This approach preserves 90-95% of the maximal respiratory capacity in frozen samples and can be applied to isolated mitochondria, permeabilized cells, and tissue homogenates with high sensitivity. We find that primary changes in mitochondrial function, detected in fresh tissue, are preserved in frozen samples years after collection. This approach will enable analysis of the integrated function of mitochondrial Complexes I to IV in one measurement, collected at remote sites or retrospectively in samples residing in tissue biobanks.


Assuntos
Criopreservação , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Mitocôndrias/metabolismo , Consumo de Oxigênio , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Masculino , Camundongos
8.
J Membr Biol ; 257(1-2): 51-61, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38315239

RESUMO

Escherichia coli is the most common microorganism causing nosocomial or community-acquired bacteremia, and extended-spectrum ß-lactamase-producing Escherichia coli isolates are identified worldwide with increasing frequency. For this reason, it is necessary to evaluate potential new molecules like antimicrobial peptides. They are recognized for their biological potential which makes them promising candidates in the fight against infections. The goal of this research was to evaluate the potential of the synthetic peptide ΔM3 on several extended-spectrum ß-lactamase producing E. coli isolates. The antimicrobial and cytotoxic activity of the peptide was spectrophotometrically determined. Additionally, the capacity of the peptide to interact with the bacterial membrane was monitored by fluorescence microscopy and infrared spectroscopy. The results demonstrated that the synthetic peptide is active against Escherichia coli isolates at concentrations similar to Meropenem. On the other hand, no cytotoxic effect was observed in HaCaT keratinocyte cells even at 10 times the minimal inhibitory concentration. Microscopy results showed a permeabilizing effect of the peptide on the bacteria. The infrared results showed that ΔM3 showed affinity for the lipids of the microorganism's membrane. The results suggest that the ∆M3 interacts with the negatively charged lipids from the E. coli by a disturbing effect on membrane. Finally, the secondary structure experiments of the peptide showed a random structure in solution that did not change during the interaction with the membranes.


Assuntos
Infecções por Escherichia coli , Escherichia coli , Humanos , Antibacterianos/farmacologia , beta-Lactamases , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Lipídeos , Peptídeos/farmacologia
9.
Semin Neurol ; 44(2): 168-177, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38485127

RESUMO

Underserved and underrepresented populations have historically been excluded from neurological research. This lack of representation has implications for translation of research findings into clinical practice given the impact of social determinants of health on neurological disease risk, progression, and outcomes. Lack of inclusion in research is driven by individual-, investigator-, and study-level barriers as well as larger systemic injustices (e.g., structural racism, discriminatory practices). Although strategies to increase inclusion of underserved and underrepresented populations have been put forth, numerous questions remain about the most effective methodology. In this article, we highlight inclusivity patterns and gaps among the most common neurological conditions and propose best practices informed by our own experiences in engagement of local community organizations and collaboration efforts to increase underserved and underrepresented population participation in neurological research.


Assuntos
Área Carente de Assistência Médica , Populações Vulneráveis , Humanos
10.
BMC Infect Dis ; 24(1): 179, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336649

RESUMO

BACKGROUND: During the COVID-19 pandemic swift implementation of research cohorts was key. While many studies focused exclusively on infected individuals, population based cohorts are essential for the follow-up of SARS-CoV-2 impact on public health. Here we present the CON-VINCE cohort, estimate the point and period prevalence of the SARS-CoV-2 infection, reflect on the spread within the Luxembourgish population, examine immune responses to SARS-CoV-2 infection and vaccination, and ascertain the impact of the pandemic on population psychological wellbeing at a nationwide level. METHODS: A representative sample of the adult Luxembourgish population was enrolled. The cohort was followed-up for twelve months. SARS-CoV-2 RT-qPCR and serology were conducted at each sampling visit. The surveys included detailed epidemiological, clinical, socio-economic, and psychological data. RESULTS: One thousand eight hundred sixty-five individuals were followed over seven visits (April 2020-June 2021) with the final weighted period prevalence of SARS-CoV-2 infection of 15%. The participants had similar risks of being infected regardless of their gender, age, employment status and education level. Vaccination increased the chances of IgG-S positivity in infected individuals. Depression, anxiety, loneliness and stress levels increased at a point of study when there were strict containment measures, returning to baseline afterwards. CONCLUSION: The data collected in CON-VINCE study allowed obtaining insights into the infection spread in Luxembourg, immunity build-up and the impact of the pandemic on psychological wellbeing of the population. Moreover, the study holds great translational potential, as samples stored at the biobank, together with self-reported questionnaire information, can be exploited in further research. TRIAL REGISTRATION: Trial registration number: NCT04379297, 10 April 2020.


Assuntos
COVID-19 , Adulto , Humanos , COVID-19/epidemiologia , SARS-CoV-2 , Pandemias , Luxemburgo/epidemiologia , Ansiedade/epidemiologia
11.
J Immunol ; 209(5): 896-906, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35914835

RESUMO

Protein kinase CK2 is a serine/threonine kinase composed of two catalytic subunits (CK2α and/or CK2α') and two regulatory subunits (CK2ß). CK2 promotes cancer progression by activating the NF-κB, PI3K/AKT/mTOR, and JAK/STAT pathways, and also is critical for immune cell development and function. The potential involvement of CK2 in CD8+ T cell function has not been explored. We demonstrate that CK2 protein levels and kinase activity are enhanced upon mouse CD8+ T cell activation. CK2α deficiency results in impaired CD8+ T cell activation and proliferation upon TCR stimulation. Furthermore, CK2α is involved in CD8+ T cell metabolic reprogramming through regulating the AKT/mTOR pathway. Lastly, using a mouse Listeria monocytogenes infection model, we demonstrate that CK2α is required for CD8+ T cell expansion, maintenance, and effector function in both primary and memory immune responses. Collectively, our study implicates CK2α as an important regulator of mouse CD8+ T cell activation, metabolic reprogramming, and differentiation both in vitro and in vivo.


Assuntos
Caseína Quinase II , NF-kappa B , Linfócitos T CD8-Positivos/metabolismo , Caseína Quinase II/metabolismo , Fosfatidilinositol 3-Quinases , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas c-akt , Receptores de Antígenos de Linfócitos T , Serina , Linfócitos T/metabolismo , Serina-Treonina Quinases TOR
12.
Nature ; 559(7712): 130-134, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29950728

RESUMO

The conserved and essential DEAD-box RNA helicase Ded1p from yeast and its mammalian orthologue DDX3 are critical for the initiation of translation1. Mutations in DDX3 are linked to tumorigenesis2-4 and intellectual disability5, and the enzyme is targeted by a range of viruses6. How Ded1p and its orthologues engage RNAs during the initiation of translation is unknown. Here we show, by integrating transcriptome-wide analyses of translation, RNA structure and Ded1p-RNA binding, that the effects of Ded1p on the initiation of translation are connected to near-cognate initiation codons in 5' untranslated regions. Ded1p associates with the translation pre-initiation complex at the mRNA entry channel and repressing the activity of Ded1p leads to the accumulation of RNA structure in 5' untranslated regions, the initiation of translation from near-cognate start codons immediately upstream of these structures and decreased protein synthesis from the corresponding main open reading frames. The data reveal a program for the regulation of translation that links Ded1p, the activation of near-cognate start codons and mRNA structure. This program has a role in meiosis, in which a marked decrease in the levels of Ded1p is accompanied by the activation of the alternative translation initiation sites that are seen when the activity of Ded1p is repressed. Our observations indicate that Ded1p affects translation initiation by controlling the use of near-cognate initiation codons that are proximal to mRNA structure in 5' untranslated regions.


Assuntos
Regiões 5' não Traduzidas/genética , Códon de Iniciação/genética , RNA Helicases DEAD-box/metabolismo , Iniciação Traducional da Cadeia Peptídica/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Reagentes de Ligações Cruzadas/química , Subunidades Ribossômicas Menores de Eucariotos/química , Subunidades Ribossômicas Menores de Eucariotos/metabolismo
13.
Support Care Cancer ; 32(2): 112, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38236480

RESUMO

PURPOSE: Nigeria has the highest burden of breast cancer (BC) in Africa. While the survival rates for BC are over 90% in many high-income countries; low-and middle-income countries like Nigeria have 40% BC survival rates. Prior studies show that the burden and poor BC survival rates are exacerbated by both health system and individual level factors, yet there is a paucity of literature on the experiences of BC survivors in Nigeria. Hence, this study explored the divergent and convergent experiences of BC survivors in accessing, navigating, and coping with treatment. METHODS: Participants (N = 24, aged 35 to 73 years) were recruited and engaged in focus group discussions (group 1, n = 11; group 2, n = 13 participants). Transcripts were transcribed verbatim and analyzed with inductive thematic analysis. RESULTS: Four themes were identified: "I am carrying this [breast cancer] alone," "Living my life," "'God' helped me," and "A very painful journey." Participants described how they concealed their BC diagnosis from family and significant others while accessing and navigating BC treatment. Also, they adopted spiritual beliefs as a coping mechanism while sticking to their treatment and acknowledging the burden of BC on their well-being. CONCLUSIONS: Our findings explored the emotional burden of BC diagnosis and treatment and the willingness of the BC survivors to find meaning in their diagnosis. Treatment for BC survivors should integrate supportive care and innovative BC access tools to reduce pain and mitigate the burdens of BC. IMPLICATIONS FOR CANCER SURVIVORS: The integration of innovative technologies for venous access and other treatment needs of BC is crucial and will improve survivorship. Non-disclosure of BC diagnosis is personal and complicated; hence, BC survivors need to be supported at various levels of care and treatment to make meaningful decisions. To improve survivorship, patient engagement is crucial in shared decision-making, collaboration, and active participation in care.


Assuntos
Neoplasias da Mama , Sobreviventes de Câncer , Humanos , Feminino , Neoplasias da Mama/terapia , Cônjuges , Sobreviventes , Sobrevivência , Dor
14.
Am J Physiol Heart Circ Physiol ; 324(4): H484-H493, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36800507

RESUMO

Mitochondrial DNA (mtDNA) haplotype regulates mitochondrial structure/function and reactive oxygen species in aortocaval fistula (ACF) in mice. Here, we unravel the mitochondrial haplotype effects on cardiomyocyte mitochondrial ultrastructure and transcriptome response to ACF in vivo. Phenotypic responses and quantitative transmission electron microscopy (TEM) and RNA sequence at 3 days were determined after sham surgery or ACF in vivo in cardiomyocytes from wild-type (WT) C57BL/6J (C57n:C57mt) and C3H/HeN (C3Hn:C3Hmt) and mitochondrial nuclear exchange mice (C57n:C3Hmt or C3Hn:C57mt). Quantitative TEM of cardiomyocyte mitochondria C3HWT hearts have more electron-dense compact mitochondrial cristae compared with C57WT. In response to ACF, mitochondrial area and cristae integrity are normal in C3HWT; however, there is mitochondrial swelling, cristae lysis, and disorganization in both C57WT and MNX hearts. Tissue analysis shows that C3HWT hearts have increased autophagy, antioxidant, and glucose fatty acid oxidation-related genes compared with C57WT. Comparative transcriptomic analysis of cardiomyocytes from ACF was dependent upon mtDNA haplotype. C57mtDNA haplotype was associated with increased inflammatory/protein synthesis pathways and downregulation of bioenergetic pathways, whereas C3HmtDNA showed upregulation of autophagy genes. In conclusion, ACF in vivo shows a protective response of C3Hmt haplotype that is in large part driven by mitochondrial nuclear genome interaction.NEW & NOTEWORTHY The results of this study support the effects of mtDNA haplotype on nuclear gene expression in cardiomyocytes. Currently, there is no acceptable therapy for volume overload due to mitral regurgitation. The findings of this study could suggest that mtDNA haplotype activates different pathways after ACF warrants further investigations on human population of heart disease from different ancestry backgrounds.


Assuntos
Insuficiência Cardíaca , Miócitos Cardíacos , Camundongos , Animais , Humanos , Miócitos Cardíacos/metabolismo , Haplótipos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , DNA Mitocondrial/genética
15.
Plant Biotechnol J ; 21(10): 2019-2032, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37421233

RESUMO

Citrus bacterial canker (CBC), caused by Xanthomonas citri subsp. citri (Xcc), causes dramatic losses to the citrus industry worldwide. Transcription activator-like effectors (TALEs), which bind to effector binding elements (EBEs) in host promoters and activate transcription of downstream host genes, contribute significantly to Xcc virulence. The discovery of the biochemical context for the binding of TALEs to matching EBE motifs, an interaction commonly referred to as the TALE code, enabled the in silico prediction of EBEs for each TALE protein. Using the TALE code, we engineered a synthetic resistance (R) gene, called the Xcc-TALE-trap, in which 14 tandemly arranged EBEs, each capable of autonomously recognizing a particular Xcc TALE, drive the expression of Xanthomonas avrGf2, which encodes a bacterial effector that induces plant cell death. Analysis of a corresponding transgenic Duncan grapefruit showed that transcription of the cell death-inducing executor gene, avrGf2, was strictly TALE-dependent and could be activated by several different Xcc TALE proteins. Evaluation of Xcc strains from different continents showed that the Xcc-TALE-trap mediates resistance to this global panel of Xcc isolates. We also studied in planta-evolved TALEs (eTALEs) with novel DNA-binding domains and found that these eTALEs also activate the Xcc-TALE-trap, suggesting that the Xcc-TALE-trap is likely to confer durable resistance to Xcc. Finally, we show that the Xcc-TALE-trap confers resistance not only in laboratory infection assays but also in more agriculturally relevant field studies. In conclusion, transgenic plants containing the Xcc-TALE-trap offer a promising sustainable approach to control CBC.


Assuntos
Citrus , Xanthomonas , Efetores Semelhantes a Ativadores de Transcrição/genética , Efetores Semelhantes a Ativadores de Transcrição/metabolismo , Citrus/genética , Citrus/microbiologia , Xanthomonas/genética , Regiões Promotoras Genéticas/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia
16.
Nitric Oxide ; 130: 22-35, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36414197

RESUMO

Limited O2 availability can decrease essential processes in energy metabolism. However, cancers have developed distinct metabolic adaptations to these conditions. For example, glutaminolysis can maintain energy metabolism and hypoxia signaling. Additionally, it has been observed that nitric oxide (NO) possesses concentration-dependent, biphasic effects in cancer. NO has potent anti-tumor effects through modulating events such as angiogenesis and metastasis at low physiological concentrations and inducing cell death at higher concentrations. In this study, Ewing Sarcoma cells (A-673), MIA PaCa, and SKBR3 cells were treated with DetaNONOate (DetaNO) in a model of hypoxia (1% O2) and reoxygenation (21% O2). All 3 cell types showed NO-dependent inhibition of cellular O2 consumption which was enhanced as O2-tension decreased. L-Gln depletion suppressed the mitochondrial response to decreasing O2 tension in all 3 cell types and resulted in inhibition of Complex I activity. In A-673 cells the O2 tension dependent change in mitochondrial O2 consumption and increase in glycolysis was dependent on the presence of L-Gln. The response to hypoxia and Complex I activity were restored by α-ketoglutarate. NO exposure resulted in the A-673 cells showing greater sensitivity to decreasing O2 tension. Under conditions of L-Gln depletion, NO restored HIF-1α levels and the mitochondrial response to O2 tension possibly through the increase of 2-hydroxyglutarate. NO also resulted in suppression of cellular bioenergetics and further inhibition of Complex I which was not rescued by α-ketoglutarate. Taken together these data suggest that NO modulates the mitochondrial response to O2 differentially in the absence and presence of L-Gln. These data suggest a combination of metabolic strategies targeting glutaminolysis and Complex I in cancer cells.


Assuntos
Neoplasias , Óxido Nítrico , Humanos , Óxido Nítrico/farmacologia , Glutamina/farmacologia , Glutamina/metabolismo , Ácidos Cetoglutáricos , Hipóxia/metabolismo , Metabolismo Energético/fisiologia
17.
BMC Med Res Methodol ; 23(1): 8, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36631766

RESUMO

BACKGROUND: In the older general population, neurodegenerative diseases (NDs) are associated with increased disability, decreased physical and cognitive function. Detecting risk factors can help implement prevention measures. Using deep neural networks (DNNs), a machine-learning algorithm could be an alternative to Cox regression in tabular datasets with many predictive features. We aimed to compare the performance of different types of DNNs with regularized Cox proportional hazards models to predict NDs in the older general population. METHODS: We performed a longitudinal analysis with participants of the English Longitudinal Study of Ageing. We included men and women with no NDs at baseline, aged 60 years and older, assessed every 2 years from 2004 to 2005 (wave2) to 2016-2017 (wave 8). The features were a set of 91 epidemiological and clinical baseline variables. The outcome was new events of Parkinson's, Alzheimer or dementia. After applying multiple imputations, we trained three DNN algorithms: Feedforward, TabTransformer, and Dense Convolutional (Densenet). In addition, we trained two algorithms based on Cox models: Elastic Net regularization (CoxEn) and selected features (CoxSf). RESULTS: 5433 participants were included in wave 2. During follow-up, 12.7% participants developed NDs. Although the five models predicted NDs events, the discriminative ability was superior using TabTransformer (Uno's C-statistic (coefficient (95% confidence intervals)) 0.757 (0.702, 0.805). TabTransformer showed superior time-dependent balanced accuracy (0.834 (0.779, 0.889)) and specificity (0.855 (0.0.773, 0.909)) than the other models. With the CoxSf (hazard ratio (95% confidence intervals)), age (10.0 (6.9, 14.7)), poor hearing (1.3 (1.1, 1.5)) and weight loss 1.3 (1.1, 1.6)) were associated with a higher DNN risk. In contrast, executive function (0.3 (0.2, 0.6)), memory (0, 0, 0.1)), increased gait speed (0.2, (0.1, 0.4)), vigorous physical activity (0.7, 0.6, 0.9)) and higher BMI (0.4 (0.2, 0.8)) were associated with a lower DNN risk. CONCLUSION: TabTransformer is promising for prediction of NDs with heterogeneous tabular datasets with numerous features. Moreover, it can handle censored data. However, Cox models perform well and are easier to interpret than DNNs. Therefore, they are still a good choice for NDs.


Assuntos
Doenças Neurodegenerativas , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Estudos de Coortes , Estudos Longitudinais , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/epidemiologia , Aprendizado de Máquina , Redes Neurais de Computação
18.
BMC Public Health ; 23(1): 1517, 2023 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-37558981

RESUMO

BACKGROUND: Im/migrants (immigrants and migrants, including refugees, asylum seekers, and individuals without legal documentation) experience unique assets and needs in relation to coronavirus disease 2019 (COVID-19). Community-based participatory research (CBPR) is one way to engage im/migrant communities. Rochester Healthy Community Partnership (RHCP) is a CBPR partnership in Rochester, Minnesota. RHCP partners noted that credible COVID-19 information was not available to their communities. In response, RHCP formed a COVID-19 Task Force and adapted the Centers for Disease Control and Prevention's Crisis and Emergency Risk Communication (CERC) framework to create an intervention that prioritized im/migrant groups experiencing health disparities. In the CERC intervention, communication leaders delivered COVID-19 health messages to their social networks and documented related concerns. RHCP relayed these concerns to regional leaders to ensure that im/migrant experiences were included in decision making. Once vaccines were available, RHCP continued to deploy the CERC intervention to promote vaccination equity. The aims of this paper are to (1) describe the implementation of a bidirectional CERC intervention for vaccination equity, and (2) describe a community-engaged and community-based vaccine clinic intervention. METHODS: First, we surveyed participants (n = 37) to assess COVID-19 experiences, acceptability of the CERC intervention, and motivation to receive a COVID-19 vaccination. Second, we collaborated with community partners to hold vaccine clinics. We report descriptive statistics from each intervention. RESULTS: When asked about the acceptability of the CERC intervention for vaccine equity, most participants either reported that they 'really liked it' or 'thought it was just ok'. Most participants stated that they would recommend the program to family or friends who have not yet received the COVID-19 vaccine. Almost all participants reported that they felt 'much more' or 'somewhat more' motivated to receive a COVID-19 vaccine after the intervention. We administered 1158 vaccines at the vaccination clinics. CONCLUSIONS: We found that participants viewed the CERC intervention for vaccination equity as an acceptable way to disseminate COVID-19-related information. Nearly all participants reported that the intervention convinced them to receive a COVID-19 vaccine. In our experience, community-engaged and community-based clinics are a successful way to administer vaccines to im/migrant communities during a pandemic.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Comunicação , Rede Social , Vacinação
19.
J Perinat Med ; 51(5): 600-606, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-36394545

RESUMO

This systematic review and meta-analysis assessed the risk of inadequate prenatal care and pregnancy outcome among incarcerated pregnant individuals in the United States. PubMed/MedLine, Embase, ClinicalTrials.gov and Web of Science were searched from inception up to March 30th, 2022. Studies were included if they reported the risk of inadequate prenatal care and/or pregnancy outcomes among incarcerated pregnant individuals in the United States jails or prisons. Adequacy of prenatal care was quantified by Kessner index. The random-effects model was used to pool the mean differences or odds ratios (OR) and the corresponding 95% confidence intervals (CIs) using RevMan software. Nine studies were included in the final review. A total of 11,534 pregnant individuals, of whom 2,544 were incarcerated while pregnant, and 8,990 who were matched non-incarcerated pregnant individuals serving as control group, were utilized. Compared to non-incarcerated pregnancies, incarcerated pregnant individuals were at higher risk of inadequate prenatal care (OR 2.99 [95% CI: 1.60, 5.61], p<0.001) and were more likely to have newborns with low birthweight (OR 1.66 [95% CI: 1.19, 2.32], p=0.003). There was no significant difference between incarcerated and matched control pregnancies in the rates of preterm birth and stillbirth. The findings of the current systematic review and meta-analysis suggest that incarcerated pregnant individuals have an increased risk of inadequate prenatal care. Considering the limited number of current studies, further research is indicated to both assess whether the risk of inadequate prenatal care has negative impact on prenatal outcomes for this population and to determine the steps that can be taken to enhance prenatal care for all pregnant individuals incarcerated in the United States prisons.


Assuntos
Resultado da Gravidez , Nascimento Prematuro , Feminino , Gravidez , Recém-Nascido , Humanos , Estados Unidos/epidemiologia , Resultado da Gravidez/epidemiologia , Cuidado Pré-Natal , Nascimento Prematuro/epidemiologia , Natimorto , Prisões
20.
Cardiol Young ; 33(9): 1569-1573, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36062556

RESUMO

MAIN AIM: To electrophysiologically determine the impact of moderate to severe chronic hypoxia (H) resulting from a wide array of CHD (HCHD) conditions on the integrity of brainstem function. MATERIALS AND METHODS: Applying brainstem auditory-evoked response methodology, 30 chronically afflicted HCHD patients, who already had undergone heart surgery, were compared to 28 healthy control children (1-15 yo) matched by age, gender and socioeconomic condition. Blood oxygen saturation was clinically determined and again immediately before brainstem auditory-evoked response testing. RESULTS: Among HCHD children, auditory wave latencies (I, III and V) were significantly longer (medians: I, 2.02 ms; III, 4.12 ms, and; V, 6.30 ms) compared to control (medians: I, 1.67ms; III, 3.72 ms, and; V, 5.65 ms), as well as interpeak intervals (HCHD medians: I-V, 4.25 ms, and; III-V, 2.25ms; control medians: I-V, 3.90 ms and, III-V, 1.80 ms) without significant differences in wave amplitudes between groups. A statistically significant and inverse correlation between average blood oxygen saturation of each group (control, 94%; HCHD, 78%) and their respective wave latencies and interpeak intervals was found. CONCLUSIONS: As determined by brainstem auditory-evoked responses, young HCHD patients manifestly show severely altered neuronal conductivity in the auditory pathway strongly correlated with their hypoxic condition. These observations are strongly supported by different brainstem neurological and image studies showing that alterations, either in microstructure or function, result from the condition of chronic hypoxia in CHD. The non-altered wave amplitudes are indicative of relatively well-preserved neuronal relay nuclei.


Assuntos
Potenciais Evocados Auditivos do Tronco Encefálico , Hipóxia , Humanos , Criança , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Tronco Encefálico
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