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1.
Cell ; 184(2): 334-351.e20, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33434495

RESUMO

Despite considerable efforts, the mechanisms linking genomic alterations to the transcriptional identity of cancer cells remain elusive. Integrative genomic analysis, using a network-based approach, identified 407 master regulator (MR) proteins responsible for canalizing the genetics of individual samples from 20 cohorts in The Cancer Genome Atlas (TCGA) into 112 transcriptionally distinct tumor subtypes. MR proteins could be further organized into 24 pan-cancer, master regulator block modules (MRBs), each regulating key cancer hallmarks and predictive of patient outcome in multiple cohorts. Of all somatic alterations detected in each individual sample, >50% were predicted to induce aberrant MR activity, yielding insight into mechanisms linking tumor genetics and transcriptional identity and establishing non-oncogene dependencies. Genetic and pharmacological validation assays confirmed the predicted effect of upstream mutations and MR activity on downstream cellular identity and phenotype. Thus, co-analysis of mutational and gene expression profiles identified elusive subtypes and provided testable hypothesis for mechanisms mediating the effect of genetic alterations.


Assuntos
Neoplasias/genética , Transcrição Gênica , Adenocarcinoma/genética , Animais , Linhagem Celular Tumoral , Neoplasias do Colo/genética , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Genoma Humano , Células HEK293 , Humanos , Camundongos Nus , Mutação/genética , Reprodutibilidade dos Testes
2.
Cell ; 179(5): 1084-1097.e21, 2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31730851

RESUMO

The ocean is home to myriad small planktonic organisms that underpin the functioning of marine ecosystems. However, their spatial patterns of diversity and the underlying drivers remain poorly known, precluding projections of their responses to global changes. Here we investigate the latitudinal gradients and global predictors of plankton diversity across archaea, bacteria, eukaryotes, and major virus clades using both molecular and imaging data from Tara Oceans. We show a decline of diversity for most planktonic groups toward the poles, mainly driven by decreasing ocean temperatures. Projections into the future suggest that severe warming of the surface ocean by the end of the 21st century could lead to tropicalization of the diversity of most planktonic groups in temperate and polar regions. These changes may have multiple consequences for marine ecosystem functioning and services and are expected to be particularly significant in key areas for carbon sequestration, fisheries, and marine conservation. VIDEO ABSTRACT.


Assuntos
Biodiversidade , Plâncton/fisiologia , Água do Mar/microbiologia , Geografia , Modelos Teóricos , Oceanos e Mares , Filogenia
3.
N Engl J Med ; 388(22): 2037-2048, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36876756

RESUMO

BACKGROUND: Data from a 5-year follow-up of outcomes after transcatheter edge-to-edge repair of severe mitral regurgitation, as compared with outcomes after maximal doses of guideline-directed medical therapy alone, in patients with heart failure are now available. METHODS: We randomly assigned patients with heart failure and moderate-to-severe or severe secondary mitral regurgitation who remained symptomatic despite the use of maximal doses of guideline-directed medical therapy to undergo transcatheter edge-to-edge repair plus receive medical therapy (device group) or to receive medical therapy alone (control group) at 78 sites in the United States and Canada. The primary effectiveness end point was all hospitalizations for heart failure through 2 years of follow-up. The annualized rate of all hospitalizations for heart failure, all-cause mortality, the risk of death or hospitalization for heart failure, and safety, among other outcomes, were assessed through 5 years. RESULTS: Of the 614 patients enrolled in the trial, 302 were assigned to the device group and 312 to the control group. The annualized rate of hospitalization for heart failure through 5 years was 33.1% per year in the device group and 57.2% per year in the control group (hazard ratio, 0.53; 95% confidence interval [CI], 0.41 to 0.68). All-cause mortality through 5 years was 57.3% in the device group and 67.2% in the control group (hazard ratio, 0.72; 95% CI, 0.58 to 0.89). Death or hospitalization for heart failure within 5 years occurred in 73.6% of the patients in the device group and in 91.5% of those in the control group (hazard ratio, 0.53; 95% CI, 0.44 to 0.64). Device-specific safety events within 5 years occurred in 4 of 293 treated patients (1.4%), with all the events occurring within 30 days after the procedure. CONCLUSIONS: Among patients with heart failure and moderate-to-severe or severe secondary mitral regurgitation who remained symptomatic despite guideline-directed medical therapy, transcatheter edge-to-edge repair of the mitral valve was safe and led to a lower rate of hospitalization for heart failure and lower all-cause mortality through 5 years of follow-up than medical therapy alone. (Funded by Abbott; COAPT ClinicalTrials.gov number, NCT01626079.).


Assuntos
Cateterismo Cardíaco , Insuficiência Cardíaca , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Humanos , Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/métodos , Seguimentos , Insuficiência Cardíaca/terapia , Insuficiência Cardíaca/cirurgia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/métodos , Insuficiência da Valva Mitral/etiologia , Insuficiência da Valva Mitral/cirurgia , Resultado do Tratamento
4.
Proc Natl Acad Sci U S A ; 120(6): e2213163120, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36716377

RESUMO

Material fluxes at the land-ocean interface impact seawater composition and global cycling of elements. However, most attention has been focused on the fluvial dissolved fluxes. For elements like lead (Pb), whose fluvial particulate flux into the ocean is two orders of magnitude higher than the dissolved counterpart, the role of particulates in elemental cycling is potentially important but currently less appreciated. Using both chemical analyses on samples collected from around equatorial Southeast Asia and model simulations, we show that particulate-dissolved exchange is an important mechanism controlling the concentration and isotopic composition of dissolved Pb in the ocean. Our model indicates that Pb contributed from particulate-dissolved exchange at ocean boundaries is larger than, or at least comparable to, other major Pb sources to the seawater before the Anthropocene, when the anthropogenic Pb was absent. Our work highlights the importance of boundary exchange in understanding marine element cycling and weathering-climate feedback.

5.
Plant Physiol ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38593032

RESUMO

Trehalose 6-phosphate (Tre6P) is an essential signal metabolite that regulates the level of sucrose, linking growth and development to the metabolic status. We hypothesized that Tre6P plays a role in mediating the regulation of gene expression by sucrose. To test this, we performed transcriptomic profiling on Arabidopsis (Arabidopsis thaliana) plants that expressed a bacterial TREHALOSE 6-PHOSPHATE SYNTHASE (TPS) under the control of an ethanol-inducible promoter. Induction led to a 4-fold rise in Tre6P levels, a concomitant decrease in sucrose, significant changes (FDR ≤ 0.05) of over 13,000 transcripts, and two-fold or larger changes of over 5000 transcripts. Comparison with nine published responses to sugar availability allowed some of these changes to be linked to the rise in Tre6P, while others were probably due to lower sucrose or other indirect effects. Changes linked to Tre6P included repression of photosynthesis-related gene expression and induction of many growth-related processes including ribosome biogenesis. About 500 starvation-related genes are known to be induced by SUCROSE-NON-FERMENTING-1-RELATED KINASE 1 (SnRK1). They were largely repressed by Tre6P in a manner consistent with SnRK1 inhibition by Tre6P. SnRK1 also represses many genes that are involved in biosynthesis and growth. These responded to Tre6P in a more complex manner, pointing toward Tre6P interacting with other C-signaling pathways. Additionally, elevated Tre6P modified the expression of genes encoding regulatory subunits of the SnRK1 complex and TPS class II and FCS-LIKE ZINC FINGER proteins that are thought to modulate SnRK1 function and genes involved in circadian, TARGET OF RAPAMYCIN-, light, abscisic acid, and other hormone signaling.

6.
Mol Psychiatry ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802507

RESUMO

Previous meta-analyses have documented the association of immune-inflammatory pathways with the pathophysiology of Major Depressive Episode (MDE), as reflected by alterations in peripheral blood immune cell counts. However, it remains unclear whether these immunological changes are distinct in individuals experiencing suicidal ideation (SI) or suicidal behavior (SB), beyond the context of an MDE. This systematic review and meta-analysis aimed to examine peripheral immune cell profiles across samples with SI/SB and compare them to healthy controls or patients with MDE. A systematic literature search was conducted in MEDLINE, Embase, and PsycINFO for articles published from inception until June 12, 2023. Two independent reviewers screened the articles for inclusion, extracted data, and assessed the risk of bias using the Newcastle-Ottawa scale. Meta-analyses were performed using a random-effects model to calculate standardized mean differences (SMDs) and 95% confidence intervals (CIs) for immune cell counts or ratios between groups with and without SI/SB. Heterogeneity across studies was assessed using the restricted maximum-likelihood estimator for tau statistic and I2-statistic and tested by the Q test. Publication bias was evaluated using the Egger´s test and funnel plots. Meta-regression analyses were conducted to explore the potential moderating effects of age, gender, current or lifetime SI/SB, and the type of self-harming behavior (SI or SB). The study was registered with PROSPERO (CRD42023433089). The systematic review included 30 studies, with data from 19 studies included in the meta-analyses comprising 139 unique comparisons. Eleven different cell populations or ratios were included, comprising 1973 individuals with SI/SB and 5537 comparison subjects. White blood cell (WBC) and neutrophil counts were higher in individuals with SI/SB than in controls (WBC: SMD = 0.458; 95% CI = 0.367-0.548; p value ≤ 0.001; I2 = 0.002% and; Neutrophils: SMD = 0.581; 95% CI = 0.408-0.753; p < 0.001), indicating an inflammatory process. The neutrophil-to-lymphocyte ratio (NLR) emerged as a potential marker, demonstrating a notable elevation in individuals with SI/SB (SMD = 0.695; 95% CI = 0.054-1.335; p value = 0.033; I2 = 94.281%; Q test p value ≤ 0.001). The elevated NLR appears to be primarily driven by the increase in neutrophil counts, as no significant differences were found in lymphocyte counts between groups. Comparisons among participants with and without SI/SB and depression revealed similar trends with increased NLR, monocyte-to-lymphocyte ratio (MLR), and platelet-to-lymphocyte ratio (PLR) observed in depressed individuals with SI/SB compared to those without SI/SB. Broad alteration in the peripheral immune cell populations and their ratios were observed in individuals with SI/SB, indicating an immune activation or dysfunction. Notably, these immunological changes were also evident when comparing MDE individuals with and without SI/SB, suggesting that such immune dysfunction associated with suicidality cannot be solely attributed to or explained by depressive symptoms. The NLR, MLR, and PLR ratios, in combination with novel immune cellular and protein biomarkers, open new avenues in understanding the immunological underpinnings of SI/SB. These findings highlight the potential utility of immune markers as part of a multi-modal approach for risk stratification and therapeutic monitoring in SI/SB.

7.
Mol Psychiatry ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879719

RESUMO

Substance use disorders (SUD) and drug addiction are major threats to public health, impacting not only the millions of individuals struggling with SUD, but also surrounding families and communities. One of the seminal challenges in treating and studying addiction in human populations is the high prevalence of co-morbid conditions, including an increased risk of contracting a human immunodeficiency virus (HIV) infection. Of the ~15 million people who inject drugs globally, 17% are persons with HIV. Conversely, HIV is a risk factor for SUD because chronic pain syndromes, often encountered in persons with HIV, can lead to an increased use of opioid pain medications that in turn can increase the risk for opioid addiction. We hypothesize that SUD and HIV exert shared effects on brain cell types, including adaptations related to neuroplasticity, neurodegeneration, and neuroinflammation. Basic research is needed to refine our understanding of these affected cell types and adaptations. Studying the effects of SUD in the context of HIV at the single-cell level represents a compelling strategy to understand the reciprocal interactions among both conditions, made feasible by the availability of large, extensively-phenotyped human brain tissue collections that have been amassed by the Neuro-HIV research community. In addition, sophisticated animal models that have been developed for both conditions provide a means to precisely evaluate specific exposures and stages of disease. We propose that single-cell genomics is a uniquely powerful technology to characterize the effects of SUD and HIV in the brain, integrating data from human cohorts and animal models. We have formed the Single-Cell Opioid Responses in the Context of HIV (SCORCH) consortium to carry out this strategy.

8.
PLoS Biol ; 20(3): e3001497, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35312677

RESUMO

Treadmilling protein filaments perform essential cellular functions by growing from one end while shrinking from the other, driven by nucleotide hydrolysis. Bacterial cell division relies on the primitive tubulin homolog FtsZ, a target for antibiotic discovery that assembles into single treadmilling filaments that hydrolyse GTP at an active site formed upon subunit association. We determined high-resolution filament structures of FtsZ from the pathogen Staphylococcus aureus in complex with different nucleotide analogs and cations, including mimetics of the ground and transition states of catalysis. Together with mutational and biochemical analyses, our structures reveal interactions made by the GTP γ-phosphate and Mg2+ at the subunit interface, a K+ ion stabilizing loop T7 for co-catalysis, new roles of key residues at the active site and a nearby crosstalk area, and rearrangements of a dynamic water shell bridging adjacent subunits upon GTP hydrolysis. We propose a mechanistic model that integrates nucleotide hydrolysis signaling with assembly-associated conformational changes and filament treadmilling. Equivalent assembly mechanisms may apply to more complex tubulin and actin cytomotive filaments that share analogous features with FtsZ.


Assuntos
Proteínas do Citoesqueleto , Nucleotídeos , Proteínas de Bactérias/metabolismo , Proteínas do Citoesqueleto/metabolismo , Guanosina Trifosfato/metabolismo , Tubulina (Proteína)
9.
J Biol Chem ; 299(3): 102941, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36702251

RESUMO

Glutamine synthetase (GS), which catalyzes the ATP-dependent synthesis of L-glutamine from L-glutamate and ammonia, is a ubiquitous and conserved enzyme that plays a pivotal role in nitrogen metabolism across all life domains. In vertebrates, GS is highly expressed in astrocytes, where its activity sustains the glutamate-glutamine cycle at glutamatergic synapses and is thus essential for maintaining brain homeostasis. In fact, decreased GS levels or activity have been associated with neurodegenerative diseases, with these alterations attributed to oxidative post-translational modifications of the protein, in particular tyrosine nitration. In this study, we expressed and purified human GS (HsGS) and performed an in-depth analysis of its oxidative inactivation by peroxynitrite (ONOO-) in vitro. We found that ONOO- exposure led to a dose-dependent loss of HsGS activity, the oxidation of cysteine, methionine, and tyrosine residues and also the nitration of tryptophan and tyrosine residues. Peptide mapping by LC-MS/MS through combined H216O/H218O trypsin digestion identified up to 10 tyrosine nitration sites and five types of dityrosine cross-links; these modifications were further scrutinized by structural analysis. Tyrosine residues 171, 185, 269, 283, and 336 were the main nitration targets; however, tyrosine-to-phenylalanine HsGS mutants revealed that their sole nitration was not responsible for enzyme inactivation. In addition, we observed that ONOO- induced HsGS aggregation and activity loss. Thiol oxidation was a key modification to elicit aggregation, as it was also induced by hydrogen peroxide treatment. Taken together, our results indicate that multiple oxidative events at various sites are responsible for the inactivation and aggregation of human GS.


Assuntos
Glutamato-Amônia Ligase , Ácido Peroxinitroso , Processamento de Proteína Pós-Traducional , Humanos , Cromatografia Líquida , Glutamato-Amônia Ligase/genética , Glutamato-Amônia Ligase/metabolismo , Ácido Peroxinitroso/química , Ácido Peroxinitroso/farmacologia , Espectrometria de Massas em Tandem , Tirosina/metabolismo , Ativação Enzimática/efeitos dos fármacos , Oxirredução , Mutação , Agregação Patológica de Proteínas/induzido quimicamente
10.
Br J Haematol ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532575

RESUMO

Peripheral T-cell lymphomas (PTCLs) are a heterogeneous group of haematological cancers with generally poor clinical outcomes. However, a subset of patients experience durable disease control, and little is known regarding long-term outcomes. The International T-cell Lymphoma Project (ITCLP) is the largest prospectively collected cohort of patients with PTCLs, providing insight into clinical outcomes at academic medical centres globally. We performed a long-term outcome analysis on patients from the ITCLP with available 10-year follow-up data (n = 735). The overall response rate to first-line therapy was 68%, while 5- and 10-year overall survival estimates were 49% and 40% respectively. Most deaths occurred prior to 5 years, and for patients alive at 5 years, the chance of surviving to 10 years was 84%. However, lymphoma remained the leading cause of death in the 5- to 10-year period (67%). Low-risk International Prognostic Index and Prognostic Index for T-cell lymphoma scores both identified patients with improved survival, while in multivariate analysis, age >60 years and Eastern Cooperative Oncology Group performance status 2-4 were associated with inferior outcomes. The favourable survival seen in patients achieving durable initial disease control emphasizes the unmet need for optimal front-line therapeutic approaches in PTCLs.

11.
Brief Bioinform ; 23(5)2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36088571

RESUMO

Cell surface proteins have been used as diagnostic and prognostic markers in cancer research and as targets for the development of anticancer agents. Many of these proteins lie at the top of signaling cascades regulating cell responses and gene expression, therefore acting as 'signaling hubs'. It has been previously demonstrated that the integrated network analysis on transcriptomic data is able to infer cell surface protein activity in breast cancer. Such an approach has been implemented in a publicly available method called 'SURFACER'. SURFACER implements a network-based analysis of transcriptomic data focusing on the overall activity of curated surface proteins, with the final aim to identify those proteins driving major phenotypic changes at a network level, named surface signaling hubs. Here, we show the ability of SURFACER to discover relevant knowledge within and across cancer datasets. We also show how different cancers can be stratified in surface-activity-specific groups. Our strategy may identify cancer-wide markers to design targeted therapies and biomarker-based diagnostic approaches.


Assuntos
Antineoplásicos , Neoplasias da Mama , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Feminino , Humanos , Proteínas de Membrana/genética , Transcriptoma
12.
Circ J ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38852997

RESUMO

BACKGROUND: Age-related changes in left ventricular (LV) structure and function lower the threshold for the onset of heart failure with preserved ejection fraction (HFpEF). LV parameters change also with race; however, the racial differences in age-related changes in LV parameters with and without adjustment for body mass index (BMI), heart rate (HR), and blood pressure (BP) remain unclear.Methods and Results: We performed a subanalysis of the World Alliance Society of Echocardiography Normal Values Study, an international cross-sectional study that examined normal echocardiographic values in 15 countries. The age-related changes in 2-dimensional echocardiographic derived parameters including LV size, systolic function, and mass, were compared between healthy Japanese (n=227) and healthy White (n=98) and Black (n=69) American participants. In men, age-related changes in all parameters did not differ significantly among races. However, compared with Japanese women, White American women had a smaller body surface area (BSA)-indexed LV volume, BSA-indexed LV internal dimension at end-systole, BSA-indexed LV stroke volume, and LV mass index to BSA, and a larger LV ejection fraction with age, even after adjusting for BMI, HR, and BP. CONCLUSIONS: Age-related changes in LV structure and function, which are important for the pathophysiology of HFpEF, may differ by race. Therefore, future studies examining echocardiographic reference values for each age group in each race are needed.

13.
Cell Mol Biol Lett ; 29(1): 44, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553684

RESUMO

Aspartate-glutamate carrier isoform 1 (AGC1) is a carrier responsible for the export of mitochondrial aspartate in exchange for cytosolic glutamate and is part of the malate-aspartate shuttle, essential for the balance of reducing equivalents in the cells. In the brain, mutations in SLC25A12 gene, encoding for AGC1, cause an ultra-rare genetic disease, reported as a neurodevelopmental encephalopathy, whose symptoms include global hypomyelination, arrested psychomotor development, hypotonia and seizures. Among the biological components most affected by AGC1 deficiency are oligodendrocytes, glial cells responsible for myelination processes, and their precursors [oligodendrocyte progenitor cells (OPCs)]. The AGC1 silencing in an in vitro model of OPCs was documented to cause defects of proliferation and differentiation, mediated by alterations of histone acetylation/deacetylation. Disrupting AGC1 activity could possibly reduce the availability of acetyl groups, leading to perturbation of many biological pathways, such as histone modifications and fatty acids formation for myelin production. Here, we explore the transcriptome of mouse OPCs partially silenced for AGC1, reporting results of canonical analyses (differential expression) and pathway enrichment analyses, which highlight a disruption in fatty acids synthesis from both a regulatory and enzymatic stand. We further investigate the cellular effects of AGC1 deficiency through the identification of most affected transcriptional networks and altered alternative splicing. Transcriptional data were integrated with differential metabolite abundance analysis, showing downregulation of several amino acids, including glutamine and aspartate. Taken together, our results provide a molecular foundation for the effects of AGC1 deficiency in OPCs, highlighting the molecular mechanisms affected and providing a list of actionable targets to mitigate the effects of this pathology.


Assuntos
Sistemas de Transporte de Aminoácidos Acídicos/deficiência , Antiporters/deficiência , Doenças Desmielinizantes Hereditárias do Sistema Nervoso Central , Doenças Mitocondriais , Células Precursoras de Oligodendrócitos , Transtornos Psicomotores , Camundongos , Animais , Regulação para Baixo/genética , Células Precursoras de Oligodendrócitos/metabolismo , Ácido Aspártico/metabolismo , Isoformas de Proteínas/metabolismo , Ácidos Graxos
14.
J Biol Chem ; 298(8): 102204, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35772495

RESUMO

The protozoan parasite Trypanosoma cruzi is the causative agent of American trypanosomiasis, otherwise known as Chagas disease. To survive in the host, the T. cruzi parasite needs antioxidant defense systems. One of these is a hybrid heme peroxidase, the T. cruzi ascorbate peroxidase-cytochrome c peroxidase enzyme (TcAPx-CcP). TcAPx-CcP has high sequence identity to members of the class I peroxidase family, notably ascorbate peroxidase (APX) and cytochrome c peroxidase (CcP), as well as a mitochondrial peroxidase from Leishmania major (LmP). The aim of this work was to solve the structure and examine the reactivity of the TcAPx-CcP enzyme. Low temperature electron paramagnetic resonance spectra support the formation of an exchange-coupled [Fe(IV)=O Trp233•+] compound I radical species, analogous to that used in CcP and LmP. We demonstrate that TcAPx-CcP is similar in overall structure to APX and CcP, but there are differences in the substrate-binding regions. Furthermore, the electron transfer pathway from cytochrome c to the heme in CcP and LmP is preserved in the TcAPx-CcP structure. Integration of steady state kinetic experiments, molecular dynamic simulations, and bioinformatic analyses indicates that TcAPx-CcP preferentially oxidizes cytochrome c but is still competent for oxidization of ascorbate. The results reveal that TcAPx-CcP is a credible cytochrome c peroxidase, which can also bind and use ascorbate in host cells, where concentrations are in the millimolar range. Thus, kinetically and functionally TcAPx-CcP can be considered a hybrid peroxidase.


Assuntos
Citocromo-c Peroxidase , Trypanosoma cruzi , Antioxidantes , Ascorbato Peroxidases/genética , Ascorbato Peroxidases/metabolismo , Ácido Ascórbico/metabolismo , Doença de Chagas/parasitologia , Citocromo-c Peroxidase/química , Citocromo-c Peroxidase/genética , Citocromo-c Peroxidase/metabolismo , Citocromos c/metabolismo , Heme/metabolismo , Humanos , Peroxidase/metabolismo , Peroxidases/metabolismo , Especificidade por Substrato , Trypanosoma cruzi/enzimologia , Trypanosoma cruzi/metabolismo
15.
Environ Microbiol ; 25(12): 3387-3405, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37915109

RESUMO

In this study, we compared the genomes of three metal-resistant bacteria isolated from mercury-contaminated soil. We identified diverse and novel MGEs with evidence of multiple LGT events shaping their genomic structure and heavy metal resistance. Among the three metal-resistant strains, Sphingobium sp SA2 and Sphingopyxis sp SE2 were resistant to multiple metals including mercury, cadmium, copper, zinc and lead. Pseudoxanthomonas sp SE1 showed resistance to mercury only. Whole genome sequencing by Illumina and Oxford Nanopore technologies was undertaken to obtain comprehensive genomic data. The Sphingobium and Sphingopyxis strains contained multiple chromosomes and plasmids, whereas the Pseudoxanthomonas strain contained one circular chromosome. Consistent with their metal resistance profiles, the strains of Sphingobium and Sphingopyxis contained a higher quantity of diverse metal resistance genes across their chromosomes and plasmids compared to the single-metal resistant Pseudoxanthomonas SE1. In all three strains, metal resistance genes were principally associated with various novel MGEs including genomic islands (GIs), integrative conjugative elements (ICEs), transposons, insertion sequences (IS), recombinase in trio (RIT) elements and group II introns, indicating their importance in facilitating metal resistance adaptation in a contaminated environment. In the Pseudoxanthomonas strain, metal resistance regions were largely situated on a GI. The chromosomes of the strains of Sphingobium and Sphingopyxis contained multiple metal resistance regions, which were likely acquired by several GIs, ICEs, numerous IS elements, several Tn3 family transposons and RIT elements. Two of the plasmids of Sphingobium were impacted by Tn3 family transposons and ISs likely integrating metal resistance genes. The two plasmids of Sphingopyxis harboured transposons, IS elements, an RIT element and a group II intron. This study provides a comprehensive annotation of complex genomic regions of metal resistance associated with novel MGEs. It highlights the critical importance of LGT in the evolution of metal resistance of bacteria in contaminated environments.


Assuntos
Elementos de DNA Transponíveis , Mercúrio , Elementos de DNA Transponíveis/genética , Genoma Bacteriano/genética , Plasmídeos/genética , Ilhas Genômicas , Bactérias/genética
16.
Brief Bioinform ; 22(2): 690-700, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33057582

RESUMO

The current outbreak of COVID-19 has generated an unprecedented scientific response worldwide, with the generation of vast amounts of publicly available epidemiological, biological and clinical data. Bioinformatics scientists have quickly produced online methods to provide non-computational users with the opportunity of analyzing such data. In this review, we report the results of this effort, by cataloguing the currently most popular web tools for COVID-19 research and analysis. Our focus was driven on tools drawing data from the fields of epidemiology, genomics, interactomics and pharmacology, in order to provide a meaningful depiction of the current state of the art of COVID-19 online resources.


Assuntos
COVID-19/prevenção & controle , Pandemias , COVID-19/virologia , Biologia Computacional , Humanos , Internet , SARS-CoV-2/isolamento & purificação
17.
Mol Psychiatry ; 27(5): 2492-2501, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35296810

RESUMO

The global crisis of opioid overdose fatalities has led to an urgent search to discover the neurobiological mechanisms of opioid use disorder (OUD). A driving force for OUD is the dysphoric and emotionally painful state (hyperkatifeia) that is produced during acute and protracted opioid withdrawal. Here, we explored a mechanistic role for extrahypothalamic stress systems in driving opioid addiction. We found that glucocorticoid receptor (GR) antagonism with mifepristone reduced opioid addiction-like behaviors in rats and zebrafish of both sexes and decreased the firing of corticotropin-releasing factor neurons in the rat amygdala (i.e., a marker of brain stress system activation). In support of the hypothesized role of glucocorticoid transcriptional regulation of extrahypothalamic GRs in addiction-like behavior, an intra-amygdala infusion of an antisense oligonucleotide that blocked GR transcriptional activity reduced addiction-like behaviors. Finally, we identified transcriptional adaptations of GR signaling in the amygdala of humans with OUD. Thus, GRs, their coregulators, and downstream systems may represent viable therapeutic targets to treat the "stress side" of OUD.


Assuntos
Transtornos Relacionados ao Uso de Opioides , Síndrome de Abstinência a Substâncias , Corticosteroides , Animais , Hormônio Liberador da Corticotropina , Ratos , Peixe-Zebra
18.
Environ Res ; 226: 115692, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36931378

RESUMO

In the Paraná River lower basin, an important agro-productive area of Argentina, crop fields and cattle breeding activities are common and may affect water quality. So, the aim of this study was to analyze the impacts of cattle breeding and agricultural activities on a stream from Buenos Aires, through physicochemical parameters (metals, pesticides, and emerging contaminants) and ecotoxicological parameters with Rhinella arenarum larvae, a native amphibian species. Three sites were selected on an ordinary plain stream that goes through agricultural fields and a cattle breeding establishment (upstream -S1-, near -S2- and downstream -S3- the establishment). Physicochemical parameters were measured in situ (in water) and in laboratory (in water and sediment samples: metals, pesticides, ivermectin and oxytetracycline). A semi-static chronic toxicity bioassay (504 h) was performed with water samples, and neurotoxicity, oxidative stress and genotoxicity biomarkers were measured after acute exposure (96 h). According to the index, a degradation in the water quality was observed in all sites. Ivermectin (8.03 mg/kg) and oxytetracycline (1.9 mg/kg) were detected in sediment samples from S2. Pesticides were detected in all sites, mainly in water samples: S1 presented the highest variability (7 residues) and in S3 AMPA, glyphosate and acetochlor concentrations were higher (10.3, 22.4 and 23.8 µg/L). Also, all sites significantly produced lethality at chronic exposure. Lethality at 504h was 40% for S1, 56.66% for S2 and 93.33% for S3. At acute exposure, the oxidative stress biomarkers were altered on R. arenarum larvae exposed to all sites and the neurotoxicity biomarkers were altered on larvae exposed to S1 and S3. Water quality was severely degraded by the surrounding agricultural and cattle breeding activities, which may represent a threat to the ecosystems.


Assuntos
Oxitetraciclina , Praguicidas , Poluentes Químicos da Água , Animais , Bovinos , Praguicidas/análise , Ecossistema , Ivermectina , Poluentes Químicos da Água/análise , Metais , Anfíbios/metabolismo , Larva/metabolismo , Biomarcadores , Monitoramento Ambiental
19.
Echocardiography ; 40(3): 188-195, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36621915

RESUMO

BACKGROUND: Assessment of left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) plays a key role in the diagnosis of cardiac amyloidosis (CA). However, manual measurements are time consuming and prone to variability. We aimed to assess whether fully automated artificial intelligence (AI) calculation of LVEF and GLS provide similar estimates and can identify abnormalities in agreement with conventional manual methods, in patients with pre-clinical and clinical CA. METHODS: We identified 51 patients (age 80 ± 10 years, 53% male) with confirmed CA according to guidelines, who underwent echocardiography before and/or at the time of CA diagnosis (median (IQR) time between observations 3.87 (1.93, 5.44 years). LVEF and GLS were quantified from the apical 2- and 4-chamber views using both manual and fully automated methods (EchoGo Core 2.0, Ultromics). Inter-technique agreement was assessed using linear regression and Bland-Altman analyses and two-way ANOVA. The diagnostic accuracy and time for detecting abnormalities (defined as LVEF ≤ 50% and GLS ≥ -15.1%, respectively) using AI was assessed by comparisons to manual measurements as a reference. RESULTS: There were no significant differences in manual and automated LVEF and GLS values in either pre-CA (p = .791 and p = .105, respectively) or at diagnosis (p = .463 and p = .722). The two methods showed strong correlation on both the pre-CA (r = .78 and r = .83) and CA echoes (r = .74 and r = .80) for LVEF and GLS, respectively. The sensitivity and specificity of AI-derived indices for detecting abnormal LVEF were 83% and 86%, respectively, in the pre-CA echo and 70% and 79% at CA diagnosis. The sensitivity and specificity of AI-derived indices for detecting abnormal GLS was 82% and 86% in the pre-CA echo and 100% and 67% at the time of CA diagnosis. There was no significant difference in the relationship between LVEF (p = .99) and GLS (p = .19) and time to abnormality between the two methods. CONCLUSION: Fully automated AI-calculated LVEF and GLS are comparable to manual measurements in patients pre-CA and at the time of CA diagnosis. The widespread implementation of automated LVEF and GLS may allow for more rapid assessment in different disease states with comparable accuracy and reproducibility to manual methods.


Assuntos
Amiloidose , Disfunção Ventricular Esquerda , Humanos , Masculino , Idoso , Idoso de 80 Anos ou mais , Feminino , Função Ventricular Esquerda , Volume Sistólico , Inteligência Artificial , Reprodutibilidade dos Testes , Deformação Longitudinal Global , Valor Preditivo dos Testes
20.
J Environ Manage ; 327: 116881, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36462484

RESUMO

Coffee consumption is concentrated in the "Global North", while production is mainly located in the "Global South". This trade-driven dependency leads to the exploitation of natural resources. As an export-oriented cash crop, such dependency jeopardizes the existence of a fair distribution of the risks and revenues among all the actors taking part in its globalized supply chain. Coffee trees are mainly rain-fed and only partly irrigated. However, the increasing global coffee demand led to higher consumption of freshwater, which can exacerbate the stressed condition of already stressed water basins. This study quantifies the impact of global coffee consumption on water scarcity, considering the larger system made of producer and consumer countries. The global displacement of such impact is driven by consumer preferences. We found that the US, EU and Asian countries' coffee consumption create impact on water scarcity mostly in African and South American countries, which is also representative of the economic disparities existing behind the global trade flows. Climate change will likely affect the varieties currently preferred by global consumers. Therefore, immediate environmental sustainability actions including water resource preservation are necessary to face current and future challenges.


Assuntos
Insegurança Hídrica , Abastecimento de Água , Recursos Hídricos , Água Doce , Água
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