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1.
Cell ; 185(17): 3153-3168.e18, 2022 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-35926507

RESUMO

The centromere represents a single region in most eukaryotic chromosomes. However, several plant and animal lineages assemble holocentromeres along the entire chromosome length. Here, we compare genome organization and evolution as a function of centromere type by assembling chromosome-scale holocentric genomes with repeat-based holocentromeres from three beak-sedge (Rhynchospora pubera, R. breviuscula, and R. tenuis) and their closest monocentric relative, Juncus effusus. We demonstrate that transition to holocentricity affected 3D genome architecture by redefining genomic compartments, while distributing centromere function to thousands of repeat-based centromere units genome-wide. We uncover a complex genome organization in R. pubera that hides its unexpected octoploidy and describe a marked reduction in chromosome number for R. tenuis, which has only two chromosomes. We show that chromosome fusions, facilitated by repeat-based holocentromeres, promoted karyotype evolution and diploidization. Our study thus sheds light on several important aspects of genome architecture and evolution influenced by centromere organization.


Assuntos
Centrômero , Cyperaceae , Animais , Centrômero/genética , Cyperaceae/genética , Evolução Molecular , Cariótipo , Plantas/genética
2.
Cell ; 184(10): 2618-2632.e17, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33836156

RESUMO

The ongoing pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is currently affecting millions of lives worldwide. Large retrospective studies indicate that an elevated level of inflammatory cytokines and pro-inflammatory factors are associated with both increased disease severity and mortality. Here, using multidimensional epigenetic, transcriptional, in vitro, and in vivo analyses, we report that topoisomerase 1 (TOP1) inhibition suppresses lethal inflammation induced by SARS-CoV-2. Therapeutic treatment with two doses of topotecan (TPT), an FDA-approved TOP1 inhibitor, suppresses infection-induced inflammation in hamsters. TPT treatment as late as 4 days post-infection reduces morbidity and rescues mortality in a transgenic mouse model. These results support the potential of TOP1 inhibition as an effective host-directed therapy against severe SARS-CoV-2 infection. TPT and its derivatives are inexpensive clinical-grade inhibitors available in most countries. Clinical trials are needed to evaluate the efficacy of repurposing TOP1 inhibitors for severe coronavirus disease 2019 (COVID-19) in humans.


Assuntos
Tratamento Farmacológico da COVID-19 , DNA Topoisomerases Tipo I/metabolismo , SARS-CoV-2/metabolismo , Inibidores da Topoisomerase I/farmacologia , Topotecan/farmacologia , Animais , COVID-19/enzimologia , COVID-19/patologia , Chlorocebus aethiops , Humanos , Inflamação/tratamento farmacológico , Inflamação/enzimologia , Inflamação/patologia , Inflamação/virologia , Mesocricetus , Camundongos , Camundongos Transgênicos , Células THP-1 , Células Vero
3.
Cell ; 183(3): 636-649.e18, 2020 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-33031745

RESUMO

Cytoplasmic accumulation of TDP-43 is a disease hallmark for many cases of amyotrophic lateral sclerosis (ALS), associated with a neuroinflammatory cytokine profile related to upregulation of nuclear factor κB (NF-κB) and type I interferon (IFN) pathways. Here we show that this inflammation is driven by the cytoplasmic DNA sensor cyclic guanosine monophosphate (GMP)-AMP synthase (cGAS) when TDP-43 invades mitochondria and releases DNA via the permeability transition pore. Pharmacologic inhibition or genetic deletion of cGAS and its downstream signaling partner STING prevents upregulation of NF-κB and type I IFN induced by TDP-43 in induced pluripotent stem cell (iPSC)-derived motor neurons and in TDP-43 mutant mice. Finally, we document elevated levels of the specific cGAS signaling metabolite cGAMP in spinal cord samples from patients, which may be a biomarker of mtDNA release and cGAS/STING activation in ALS. Our results identify mtDNA release and cGAS/STING activation as critical determinants of TDP-43-associated pathology and demonstrate the potential for targeting this pathway in ALS.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , DNA Mitocondrial/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Membrana/metabolismo , Poro de Transição de Permeabilidade Mitocondrial/metabolismo , Nucleotidiltransferases/metabolismo , Alarminas/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Citoplasma/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Células HEK293 , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Inflamação/metabolismo , Interferon Tipo I/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , NF-kappa B/metabolismo , Degeneração Neural/patologia , Fosfotransferases (Aceptor do Grupo Álcool) , Subunidades Proteicas/metabolismo , Transdução de Sinais
4.
Nature ; 624(7992): 602-610, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38093003

RESUMO

Indigenous Australians harbour rich and unique genomic diversity. However, Aboriginal and Torres Strait Islander ancestries are historically under-represented in genomics research and almost completely missing from reference datasets1-3. Addressing this representation gap is critical, both to advance our understanding of global human genomic diversity and as a prerequisite for ensuring equitable outcomes in genomic medicine. Here we apply population-scale whole-genome long-read sequencing4 to profile genomic structural variation across four remote Indigenous communities. We uncover an abundance of large insertion-deletion variants (20-49 bp; n = 136,797), structural variants (50 b-50 kb; n = 159,912) and regions of variable copy number (>50 kb; n = 156). The majority of variants are composed of tandem repeat or interspersed mobile element sequences (up to 90%) and have not been previously annotated (up to 62%). A large fraction of structural variants appear to be exclusive to Indigenous Australians (12% lower-bound estimate) and most of these are found in only a single community, underscoring the need for broad and deep sampling to achieve a comprehensive catalogue of genomic structural variation across the Australian continent. Finally, we explore short tandem repeats throughout the genome to characterize allelic diversity at 50 known disease loci5, uncover hundreds of novel repeat expansion sites within protein-coding genes, and identify unique patterns of diversity and constraint among short tandem repeat sequences. Our study sheds new light on the dimensions and dynamics of genomic structural variation within and beyond Australia.


Assuntos
Povos Aborígenes Australianos e Ilhéus do Estreito de Torres , Genoma Humano , Variação Estrutural do Genoma , Humanos , Alelos , Austrália/etnologia , Povos Aborígenes Australianos e Ilhéus do Estreito de Torres/genética , Conjuntos de Dados como Assunto , Variações do Número de Cópias de DNA/genética , Loci Gênicos/genética , Genética Médica , Variação Estrutural do Genoma/genética , Genômica , Mutação INDEL/genética , Sequências Repetitivas Dispersas/genética , Repetições de Microssatélites/genética , Genoma Humano/genética
5.
Nature ; 608(7924): 757-765, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35948641

RESUMO

The notion that mobile units of nucleic acid known as transposable elements can operate as genomic controlling elements was put forward over six decades ago1,2. However, it was not until the advancement of genomic sequencing technologies that the abundance and repertoire of transposable elements were revealed, and they are now known to constitute up to two-thirds of mammalian genomes3,4. The presence of DNA regulatory regions including promoters, enhancers and transcription-factor-binding sites within transposable elements5-8 has led to the hypothesis that transposable elements have been co-opted to regulate mammalian gene expression and cell phenotype8-14. Mammalian transposable elements include recent acquisitions and ancient transposable elements that have been maintained in the genome over evolutionary time. The presence of ancient conserved transposable elements correlates positively with the likelihood of a regulatory function, but functional validation remains an essential step to identify transposable element insertions that have a positive effect on fitness. Here we show that CRISPR-Cas9-mediated deletion of a transposable element-namely the LINE-1 retrotransposon Lx9c11-in mice results in an exaggerated and lethal immune response to virus infection. Lx9c11 is critical for the neogenesis of a non-coding RNA (Lx9c11-RegoS) that regulates genes of the Schlafen family, reduces the hyperinflammatory phenotype and rescues lethality in virus-infected Lx9c11-/- mice. These findings provide evidence that a transposable element can control the immune system to favour host survival during virus infection.


Assuntos
Elementos de DNA Transponíveis , Interações entre Hospedeiro e Microrganismos , Imunidade , Retroelementos , Viroses , Animais , Sistemas CRISPR-Cas/genética , Elementos de DNA Transponíveis/genética , Elementos de DNA Transponíveis/imunologia , Evolução Molecular , Interações entre Hospedeiro e Microrganismos/genética , Interações entre Hospedeiro e Microrganismos/imunologia , Imunidade/genética , Camundongos , RNA não Traduzido/genética , Sequências Reguladoras de Ácido Nucleico/genética , Retroelementos/genética , Retroelementos/imunologia , Viroses/genética , Viroses/imunologia
6.
Proc Natl Acad Sci U S A ; 119(49): e2201573119, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36445969

RESUMO

We investigate financial market dynamics by introducing a heterogeneous agent-based opinion formation model. In this work, we organize individuals in a financial market according to their trading strategy, namely, whether they are noise traders or fundamentalists. The opinion of a local majority compels the market exchanging behavior of noise traders, whereas the global behavior of the market influences the decisions of fundamentalist agents. We introduce a noise parameter, q, to represent the level of anxiety and perceived uncertainty regarding market behavior, enabling the possibility of adrift financial action. We place individuals as nodes in an Erdös-Rényi random graph, where the links represent their social interactions. At any given time, individuals assume one of two possible opinion states ±1 regarding buying or selling an asset. The model exhibits fundamental qualitative and quantitative real-world market features such as the distribution of logarithmic returns with fat tails, clustered volatility, and the long-term correlation of returns. We use Student's t distributions to fit the histograms of logarithmic returns, showing a gradual shift from a leptokurtic to a mesokurtic regime depending on the fraction of fundamentalist agents. Furthermore, we compare our results with those concerning the distribution of the logarithmic returns of several real-world financial indices.


Assuntos
Transtornos de Ansiedade , Ansiedade , Humanos , Interação Social
7.
Am J Physiol Cell Physiol ; 327(4): C1143-C1149, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39159390

RESUMO

The renin-angiotensin system (RAS) is composed of a series of peptides, receptors, and enzymes that play a pivotal role in maintaining cardiovascular homeostasis. Among the most important players in this system are the angiotensin-II and angiotensin-(1-7) peptides. Our group has recently demonstrated that alamandine (ALA), a peptide with structural and functional similarities to angiotensin-(1-7), interacts with cardiomyocytes, enhancing contractility via the Mas-related G protein-coupled receptor member D (MrgD). It is currently unknown whether this modulation varies along the distinct phases of the day. To address this issue, we assessed the ALA-induced contractility response of cardiomyocytes from mice at four Zeitgeber times (ZTs). At ZT2 (light phase), ALA enhanced cardiomyocyte shortening in an MrgD receptor-dependent manner, which was associated with nitric oxide (NO) production. At ZT14 (dark phase), ALA induced a negative modulation on the cardiomyocyte contraction. ß-Alanine, an MrgD agonist, reproduced the time-of-day effects of ALA on myocyte shortening. NG-nitro-l-arginine methyl ester, an NO synthase inhibitor, blocked the increase in fractional shortening induced by ALA at ZT2. No effect of ALA on myocyte shortening was observed at ZT8 and ZT20. Our results show that ALA/MrgD signaling in cardiomyocytes is subject to temporal modulation. This finding has significant implications for pharmacological approaches that combine chronotherapy for cardiac conditions triggered by disruption of circadian rhythms and hormonal signaling.NEW & NOTEWORTHY Alamandine, a member of the renin-angiotensin system, serves critical roles in cardioprotection, including the modulation of cardiomyocyte contractility. Whether this effect varies along the day is unknown. Our results provide evidence that alamandine via receptor MrgD exerts opposing actions on cardiomyocyte shortening, enhancing, or reducing contraction depending on the time of day. These findings may have significant implications for the development and effectiveness of future cardiac therapies.


Assuntos
Contração Miocárdica , Miócitos Cardíacos , Óxido Nítrico , Oligopeptídeos , Receptores Acoplados a Proteínas G , Animais , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Contração Miocárdica/fisiologia , Camundongos , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Óxido Nítrico/metabolismo , Oligopeptídeos/farmacologia , Camundongos Endogâmicos C57BL , Ritmo Circadiano/fisiologia , Ritmo Circadiano/efeitos dos fármacos , Receptores de Neuropeptídeos/metabolismo , Receptores de Neuropeptídeos/agonistas , Receptores de Neuropeptídeos/antagonistas & inibidores , Masculino , Células Cultivadas , Sistema Renina-Angiotensina/efeitos dos fármacos , Sistema Renina-Angiotensina/fisiologia
8.
Emerg Infect Dis ; 30(9): 1850-1864, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39173663

RESUMO

Plague is a deadly zoonosis that still poses a threat in many regions of the world. We combined epidemiologic, host, and vector surveillance data collected during 1961-1980 from the Araripe Plateau focus in northeastern Brazil with ecologic, geoclimatic, and Yersinia pestis genomic information to elucidate how these factors interplay in plague activity. We identified well-delimited plague hotspots showing elevated plague risk in low-altitude areas near the foothills of the plateau's concave sectors. Those locations exhibited distinct precipitation and vegetation coverage patterns compared with the surrounding areas. We noted a seasonal effect on plague activity, and human cases linearly correlated with precipitation and rodent and flea Y. pestis positivity rates. Genomic characterization of Y. pestis strains revealed a foundational strain capable of evolving into distinct genetic variants, each linked to temporally and spatially constrained plague outbreaks. These data could identify risk areas and improve surveillance in other plague foci within the Caatinga biome.


Assuntos
Peste , Yersinia pestis , Peste/epidemiologia , Peste/microbiologia , Brasil/epidemiologia , Yersinia pestis/genética , Humanos , Animais , Epidemias , Sifonápteros/microbiologia , Genoma Bacteriano , Genômica/métodos , Estações do Ano
9.
Int J Cancer ; 155(4): 719-730, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38648380

RESUMO

There is a gap in the understanding of the barriers to cancer screening participation and complying with downstream management in the Community of Latin American and Caribbean states (CELAC). Our study aimed to assess barriers across the cancer screening pathway from the health system perspective, and interventions in place to improve screening in CELAC. A standardized tool was used to collect information on the barriers across the screening pathway through engagement with the health authorities of 27 member states of CELAC. Barriers were organized in a framework adapted from the Tanahashi conceptual model and consisted of the following dimensions: availability of services, access (covering accessibility and affordability), acceptability, user-provider interaction, and effectiveness of services (which includes governance, protocols and guidelines, information system, and quality assurance). The tool also collected information of interventions in place, categorized in user-directed interventions to increase demand, user-directed interventions to increase access, provider-directed interventions, and policy and system-level interventions. All countries prioritized barriers related to the information systems, such as the population register not being accurate or complete (N = 19; 70.4%). All countries implemented some kind of intervention to improve cancer screening, group education being the most reported (N = 23; 85.2%). Training on screening delivery was the most referred provider-directed intervention (N = 19; 70.4%). The study has identified several barriers to the implementation of cancer screening in the region and interventions in place to overcome some of the barriers. Further analysis is required to evaluate the effectiveness of these interventions in achieving their objectives.


Assuntos
Detecção Precoce de Câncer , Acessibilidade aos Serviços de Saúde , Neoplasias , Humanos , América Latina , Detecção Precoce de Câncer/estatística & dados numéricos , Região do Caribe/epidemiologia , Neoplasias/diagnóstico , Neoplasias/prevenção & controle , Feminino
10.
Ann Surg ; 280(2): 202-211, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38984800

RESUMO

OBJECTIVE: To determine whether daily postoperative step goals and feedback through a fitness tracker (FT) reduce the rate of postoperative complications after surgery. BACKGROUND: Early and enhanced postoperative mobilization has been advocated to reduce postoperative complications, but it is unknown whether FT alone can reduce morbidity. METHODS: EXPELLIARMUS was performed at 11 University Hospitals across Germany by the student-led clinical trial network SIGMA. Patients undergoing major abdominal surgery were enrolled, equipped with an FT, and randomly assigned to the experimental (visible screen) or control intervention (blackened screen). The experimental group received daily step goals and feedback through the FT. The primary end point was postoperative morbidity within 30 days using the Comprehensive Complication Index (CCI). All trial visits were performed by medical students in the hospital with the opportunity to consult a surgeon-facilitator who also obtained informed consent. After discharge, medical students performed the 30-day postoperative visit through telephone and electronic questionnaires. RESULTS: A total of 347 patients were enrolled. Baseline characteristics were comparable between the 2 groups. The mean age of patients was 58 years, and 71% underwent surgery for malignant disease, with the most frequent indications being pancreatic, colorectal, and hepatobiliary malignancies. Roughly one-third of patients underwent laparoscopic surgery. No imputation for the primary end point was necessary as data completeness was 100%. There was no significant difference in the CCI between the 2 groups in the intention-to-treat analysis (mean±SD CCI experimental group: 23±24 vs. control: 22±22; 95% CI: -6.1, 3.7; P=0.628). All secondary outcomes, including quality of recovery, 6-minute walking test, length of hospital stay, and step count until postoperative day 7 were comparable between the 2 groups. CONCLUSIONS: Daily step goals combined with FT-based feedback had no effect on postoperative morbidity. The EXPELLIARMUS shows that medical students can successfully conduct randomized controlled trials in surgery.


Assuntos
Abdome , Monitores de Aptidão Física , Complicações Pós-Operatórias , Humanos , Masculino , Feminino , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/epidemiologia , Pessoa de Meia-Idade , Abdome/cirurgia , Idoso , Alemanha , Deambulação Precoce , Estudantes de Medicina
11.
Ann Surg ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39114920

RESUMO

OBJECTIVE: The aim of this study was a prospective validation of the recently established ISGPS pancreas classification as a parenchymal risk classification system for pancreatic fistula after pancreatoduodenectomy. SUMMARY BACKGROUND DATA: Postoperative pancreatic fistula (POPF) is the major driver for complications after partial pancreatoduodenectomy (PD). Recently, the International Study Group for Pancreatic Surgery (ISGPS) published a pancreas classification containing the parameters main pancreatic duct diameter (MPD) and pancreatic texture to help assess the risk of POPF development following pancreatoduodenectomy. METHODS: From January 2020 to July 2021, 271 patients receiving elective PD were included after informed consent. The postoperative course was documented prospectively up to postoperative day 30. Among the pancreas characteristics, MPD and pancreatic texture were assessed intraoperatively at the pancreatic resection margin and the pancreatic glands were assigned to one of the four pancreas classes according to the ISGPS (A to D). The primary endpoint was POPF according to the updated ISGPS definition. Secondary endpoints comprised other post-PD morbidity and mortality. RESULTS: Of 271 patients, 264 had available data according to the ISGPS pancreas classification. Of those, 78 were assigned to class A (30%), 53 to class B (20%), 50 to class C (19%) and 83 to class D (31%). POPF occurred in 54 of 271 patients (19.9%). The 30-day mortality was 7/271 (2.6%), with 6/7 having developed POPF (86%). POPF rates within the classes A, B, C and D were 9.0%, 11.3%, 20.0% and 37.4%, respectively (P<0.001). In the univariable regression analysis, only patients in pancreas class D demonstrated a significantly higher risk for POPF when compared to class A (OR 6.05, 95%-CI: 2.6-15.9, P<0.001). In the multivariable regression model, patients in class D had a significantly higher risk for POPF compared to class A (OR 3.45, 95%-CI: 1.15-11.3, P=0.032). The model comprised Body Mass Index, surgery duration, microscopic fibrosis and the ISGPS pancreas classification, demonstrating an AUC-value of approximately 0.82 when tested on the PARIS dataset. CONCLUSION: This prospective trial shows that the ISGPS pancreas classification is valid. Patients in risk class D are prone to POPF independently of other factors. Therefore, all future publications on pancreatic surgery should report the risk class according to the ISGPS pancreas classification to allow for a better comparison of reported cohorts.

12.
Development ; 148(17)2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34414417

RESUMO

Branchio-oto-renal syndrome (BOR) is a disorder characterized by hearing loss, and craniofacial and/or renal defects. Variants in the transcription factor Six1 and its co-factor Eya1, both of which are required for otic development, are linked to BOR. We previously identified Sobp as a potential Six1 co-factor, and SOBP variants in mouse and humans cause otic phenotypes; therefore, we asked whether Sobp interacts with Six1 and thereby may contribute to BOR. Co-immunoprecipitation and immunofluorescence experiments demonstrate that Sobp binds to and colocalizes with Six1 in the cell nucleus. Luciferase assays show that Sobp interferes with the transcriptional activation of Six1+Eya1 target genes. Experiments in Xenopus embryos that either knock down or increase expression of Sobp show that it is required for formation of ectodermal domains at neural plate stages. In addition, altering Sobp levels disrupts otic vesicle development and causes craniofacial cartilage defects. Expression of Xenopus Sobp containing the human variant disrupts the pre-placodal ectoderm similar to full-length Sobp, but other changes are distinct. These results indicate that Sobp modifies Six1 function and is required for vertebrate craniofacial development, and identify Sobp as a potential candidate gene for BOR.


Assuntos
Desenvolvimento Ósseo , Proteínas de Homeodomínio/metabolismo , Metaloproteínas/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Xenopus/metabolismo , Animais , Síndrome Brânquio-Otorrenal/embriologia , Síndrome Brânquio-Otorrenal/genética , Núcleo Celular/metabolismo , Orelha Interna/embriologia , Orelha Interna/metabolismo , Ectoderma/embriologia , Ectoderma/metabolismo , Expressão Gênica , Proteínas de Homeodomínio/genética , Larva/crescimento & desenvolvimento , Metaloproteínas/genética , Crista Neural/embriologia , Crista Neural/metabolismo , Proteínas Nucleares/genética , Ligação Proteica , Proteínas Tirosina Fosfatases/metabolismo , Ativação Transcricional , Proteínas de Xenopus/genética , Xenopus laevis
13.
Small ; 20(3): e2304547, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37621039

RESUMO

The electrogeneration of hydrogen peroxide (H2 O2 ) via the oxygen reduction reaction is a crucial process for advanced water treatment technologies. While significant effort is being devoted to developing highly reactive materials, gas provision systems used in these processes are receiving less attention. Here, using oxygen nanobubbles to improve the gas efficiency of the electrogeneration of H2 O2 is proposed. Aeration with nanobubbles is compared to aeration with macrobubbles under an identical experimental set-up, with nanobubbles showing a much higher gas-liquid volumetric mass transfer coefficient (KL a) of 2.6 × 10-2 min-1 compared to 2.7 × 10-4 min-1 for macrobubbles. Consequently, nanobubbles exhibit a much higher gas efficiency using 60% of O2 delivered to the system compared to 0.19% for macrobubbles. Further, it is observed that the electrogeneration of H2 O2 using carbon felt electrodes is enhanced using nanobubbles. Under the same dissolved oxygen levels, nanobubbles boost the reaction yield to 84%, while macrobubbles yield only 53.8%. To the authors' knowledge, this is the first study to investigate the use of nanobubbles in electrochemical reactions and demonstrate their ability to enhance gas efficiency and electrocatalytic response. These findings have important implications for developing more efficient chemical and electrochemical processes operating under gas-starving systems.

14.
Crit Care Med ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39177437

RESUMO

OBJECTIVES: Significant practice variation exists in the amount of resuscitative IV fluid given to patients with sepsis. Current research suggests equipoise between a tightly restrictive or more liberal strategy but data is lacking on a wider range of resuscitation practices. We sought to examine the relationship between a wide range of fluid resuscitation practices and sepsis mortality and then identify the primary driver of this practice variation. DESIGN: Retrospective analysis of the Premier Healthcare Database. SETTING: Six hundred twelve U.S. hospitals. PATIENTS: Patients with sepsis and septic shock admitted from the emergency department to the ICU from January 1, 2016, to December 31, 2019. INTERVENTIONS: The volume of resuscitative IV fluid administered before the end of hospital day- 1 and mortality. MEASUREMENTS AND MAIN RESULTS: In total, 190,682 patients with sepsis and septic shock were included in the analysis. Based upon patient characteristics and illness severity, we predicted that physicians should prescribe patients with sepsis a narrow mean range of IV fluid (95% range, 3.6-4.5 L). Instead, we observed wide variation in the mean IV fluids administered (95% range, 1.7-7.4 L). After splitting the patients into five groups based upon attending physician practice, we observed patients in the moderate group (4.0 L; interquartile range [IQR], 2.4-5.1 L) experienced a 2.5% reduction in risk-adjusted mortality compared with either the very low (1.6 L; IQR, 1.0-2.5 L) or very high (6.1 L; IQR, 4.0-9.0 L) fluid groups p < 0.01). An analysis of within- and between-hospital IV fluid resuscitation practices showed that physician variation within hospitals instead of practice differences between hospitals accounts for the observed variation. CONCLUSIONS: Individual physician practice drives excess variation in the amount of IV fluid given to patients with sepsis. A moderate approach to IV fluid resuscitation is associated with decreased sepsis mortality and should be tested in future randomized controlled trials.

15.
Bioinformatics ; 39(4)2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36943380

RESUMO

MOTIVATION: Deep learning attained excellent results in digital pathology recently. A challenge with its use is that high quality, representative training datasets are required to build robust models. Data annotation in the domain is labor intensive and demands substantial time commitment from expert pathologists. Active learning (AL) is a strategy to minimize annotation. The goal is to select samples from the pool of unlabeled data for annotation that improves model accuracy. However, AL is a very compute demanding approach. The benefits for model learning may vary according to the strategy used, and it may be hard for a domain specialist to fine tune the solution without an integrated interface. RESULTS: We developed a framework that includes a friendly user interface along with run-time optimizations to reduce annotation and execution time in AL in digital pathology. Our solution implements several AL strategies along with our diversity-aware data acquisition (DADA) acquisition function, which enforces data diversity to improve the prediction performance of a model. In this work, we employed a model simplification strategy [Network Auto-Reduction (NAR)] that significantly improves AL execution time when coupled with DADA. NAR produces less compute demanding models, which replace the target models during the AL process to reduce processing demands. An evaluation with a tumor-infiltrating lymphocytes classification application shows that: (i) DADA attains superior performance compared to state-of-the-art AL strategies for different convolutional neural networks (CNNs), (ii) NAR improves the AL execution time by up to 4.3×, and (iii) target models trained with patches/data selected by the NAR reduced versions achieve similar or superior classification quality to using target CNNs for data selection. AVAILABILITY AND IMPLEMENTATION: Source code: https://github.com/alsmeirelles/DADA.


Assuntos
Aprendizado Profundo , Redes Neurais de Computação , Software , Processamento de Imagem Assistida por Computador , Curadoria de Dados
16.
Rheumatology (Oxford) ; 63(2): 456-465, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37216912

RESUMO

OBJECTIVES: To test the association of use of antimalarials with the overall safety of treatment in RA patients receiving one or multiple courses of biologic (b)DMARDs or a Janus kinase inhibitor (JAKi). METHODS: BiobadaBrasil is a multicentric registry-based cohort study of Brazilian patients with rheumatic diseases starting their first bDMARD or JAKi. The present analysis includes RA patients recruited from January 2009 to October 2019, followed up over one or multiple (up to six) courses of treatment (latest date, 19 November 2019). The primary outcome was the incidence of serious adverse events (SAEs). Total and system-specific adverse events (AEs) and treatment interruption served as secondary outcomes. Negative binomial regression with generalized estimating equations (to estimate multivariate incidence rate ratios, mIRR) and frailty Cox proportional hazards models were used for statistical analyses. RESULTS: The number of patients enrolled was 1316 (2335 treatment courses, 6711 patient-years [PY]; 1254.5 PY on antimalarials). The overall incidence of SAEs was 9.2/100 PY. Antimalarials were associated with reduced risk of SAEs (mIRR: 0.49; 95% CI: 0.36, 0.68; P < 0.001), total AEs (0.68; 95% CI: 0.56, 0.81; P < 0.001), serious infections (0.53; 95% CI: 0.34, 0.84; P = 0.007) and total hepatic AEs (0.21; 95% CI: 0.05, 0.85; P = 0.028). Antimalarials were also related to better survival of treatment course (P = 0.003). There was no significant increase in the risk of cardiovascular AEs. CONCLUSION: Among RA patients on treatment with bDMARDs or JAKi, concomitant use of antimalarials was associated with reduced the incidence of serious and total AEs and with longer treatment course survival.


Assuntos
Antimaláricos , Antirreumáticos , Artrite Reumatoide , Produtos Biológicos , Inibidores de Janus Quinases , Humanos , Inibidores de Janus Quinases/efeitos adversos , Antimaláricos/efeitos adversos , Estudos de Coortes , Artrite Reumatoide/epidemiologia , Antirreumáticos/efeitos adversos , Produtos Biológicos/uso terapêutico
17.
Ann Surg Oncol ; 31(9): 6180-6192, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38954094

RESUMO

BACKGROUND: The use of surgery in patients with locally advanced pancreatic cancer (LAPC) following induction chemotherapy is increasing. However, most series do not report on the total cohort of patients undergoing surgical exploration; therefore, this single-center study investigates outcomes among all consecutive patients with LAPC who underwent surgical exploration. METHODS: We conducted a retrospective, single-center analysis including all consecutive patients with LAPC (Dutch Pancreatic Cancer Group criteria) who underwent surgical exploration with curative intent (January 2014-June 2023) after induction therapy. Primary outcomes were resection rate and overall survival (OS) from the time of diagnosis. RESULTS: Overall, 127 patients underwent surgical exploration for LAPC, whereby 100 patients (78.7%) underwent resection and 27 patients (21.3%) underwent a non-therapeutic laparotomy due to the extent of vascular involvement (n = 11, 8.7%) or occult metastases (n = 16, 12.6%). The overall in-hospital/30-day mortality rate was 0.8% and major morbidity was 31.3% (in patients after resection: 1.0% and 33.3%, respectively). The overall 90-day mortality rate was 5.5%, which included 3.1% mortality due to disease progression. Resection was associated with longer median OS {29 months (95% confidence interval [CI] 26-43) vs. 17 months (95% CI 11-26); p < 0.001} compared with patients undergoing non-therapeutic laparotomy, with corresponding 5-year OS rates of 28.4% and 7.7%. In Cox proportional hazard regression analysis, only pancreatic body/tail tumors independently predicted OS (hazard ratio 1.788 [95% CI 1.042-3.068]). CONCLUSION: This single-center series found a resection rate of 78.7% in patients with LAPC selected for surgical exploration, with a low risk of mortality and morbidity in all explored patients and a 5-year OS rate after resection of 28.4%.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Quimioterapia de Indução , Pancreatectomia , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/cirurgia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/mortalidade , Masculino , Feminino , Estudos Retrospectivos , Taxa de Sobrevida , Pessoa de Meia-Idade , Idoso , Seguimentos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Prognóstico , Terapia Neoadjuvante/mortalidade , Adulto
18.
Plant Cell Environ ; 47(3): 782-798, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37994626

RESUMO

The relationship between plants and pollinators is known to be influenced by ecological interactions with other community members. While most research has focused on aboveground communities affecting plant-pollinator interactions, it is increasingly recognized that soil-dwelling organisms can directly or indirectly impact these interactions. Although studies have examined the effects of arbuscular mycorrhizal fungi on floral traits, there is a gap in research regarding similar effects associated with plant growth-promoting rhizobacteria (PGPR), particularly concerning floral scent. Our study aimed to investigate the influence of the PGPR Bacillus amyloliquefaciens on the floral traits of wild (Solanum habrochaites, Solanum pimpinellifolium and Solanum peruvianum) and cultivated tomato (Solanum lycopersicum), as well as the impact of microbially-driven changes in floral scent on the foraging behaviour of the stingless bee Melipona quadrifasciata. Our findings revealed that inoculating tomatoes with PGPR led to an increased number of flowers and enhanced overall floral volatile emission. Additionally, we observed higher flower biomass and pollen levels in all species, except S. peruvianum. Importantly, these changes in volatile emissions influenced the foraging behaviour of M. quadrifasciata significantly. Our results highlight the impact of beneficial soil microbes on plant-pollinator interactions, shedding light on the multiple effects that plant-microbial interactions can have on aboveground organisms.


Assuntos
Solanum lycopersicum , Solanum , Animais , Polinização , Flores , Plantas , Pólen , Solo
19.
Histopathology ; 84(1): 6-17, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37872108

RESUMO

Advancements in the classification of lung adenocarcinoma have resulted in significant changes in pathological reporting. The eighth edition of the tumour-node-metastasis (TNM) staging guidelines calls for the use of invasive size in staging in place of total tumour size. This shift improves prognostic stratification and requires a more nuanced approach to tumour measurements in challenging situations. Similarly, the adoption of new grading criteria based on the predominant and highest-grade pattern proposed by the International Association for the Study of Lung Cancer (IASLC) shows improved prognostication, and therefore clinical utility, relative to previous grading systems. Spread through airspaces (STAS) is a form of tumour invasion involving tumour cells spreading through the airspaces, which has been highly researched in recent years. This review discusses updates in pathological T staging, adenocarcinoma grading and STAS and illustrates the utility and limitations of current concepts in lung adenocarcinoma.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Neoplasias Pulmonares , Humanos , Invasividade Neoplásica/patologia , Adenocarcinoma de Pulmão/patologia , Neoplasias Pulmonares/patologia , Adenocarcinoma/patologia , Prognóstico , Estadiamento de Neoplasias , Estudos Retrospectivos , Recidiva Local de Neoplasia/patologia
20.
Glob Chang Biol ; 30(1): e16994, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37916608

RESUMO

The O2 content of the global ocean has been declining progressively over the past decades, mainly because of human activities and global warming. Nevertheless, how long-term deoxygenation affects macrobenthic communities, sediment biogeochemistry and their mutual feedback remains poorly understood. Here, we evaluate the response of the benthic assemblages and biogeochemical functioning to decreasing O2 concentrations along the persistent bottom-water dissolved O2 gradient of the Estuary and Gulf of St. Lawrence (QC, Canada). We report several of non-linear biodiversity and functional responses to decreasing O2 concentrations, and identify an O2 threshold that occurs at approximately at 63 µM. Below this threshold, macrobenthic community assemblages change, and bioturbation rates drastically decrease to near zero. Consequently, the sequence of electron acceptors used to metabolize the sedimentary organic matter is squeezed towards the sediment surface while reduced compounds accumulate closer (as much as 0.5-2.5 cm depending on the compound) to the sediment-water interface. Our results illustrate the capacity of bioturbating species to compensate for the biogeochemical consequences of hypoxia and can help to predict future changes in benthic ecosystems.


Les teneurs en O2 de l'océan mondial ont diminué progressivement au cours des dernières décennies, principalement en raison des activités humaines et du réchauffement climatique. Néanmoins, les effets à long terme de la désoxygénation sur les communautés macrobenthiques, la biogéochimie des sédiments et leurs interactions mutuelles demeurent mal compris. Dans cette étude, nous évaluons la réponse des assemblages de macrofaune benthiques et de la dynamique biogéochimique sédimentaire aux concentrations décroissantes d'O2 le long du gradient persistant d'O2 dissous dans l'eau de fond de l'estuaire et du golfe du Saint-Laurent (QC, Canada). Nous avons observé plusieurs réponses non linéaires de la biodiversité et de la dynamique biogéochimique sédimentaire face à la diminution de la concentration en O2 avec un seuil situé à environ 63 µM. En dessous de ce seuil, les assemblages de communautés macrobenthiques changent, et les taux de bioturbation diminuent drastiquement pour atteindre des niveaux presque nuls. En conséquence, la séquence des accepteurs d'électrons utilisés pour minéraliser la matière organique sédimentaire se contracte vers la surface du sédiment, tandis que les composés réduits s'accumulent plus près (jusqu'à 0.5 à 2.5 cm selon le composé) de l'interface sédiment-eau. Nos résultats illustrent la capacité des espèces bioturbatrices à compenser les conséquences biogéochimiques de la désoxygénation et peuvent contribuer à prédire les futurs changements dans les écosystèmes benthiques.


Assuntos
Ecossistema , Sedimentos Geológicos , Humanos , Sedimentos Geológicos/química , Biodiversidade , Água , Oceanos e Mares
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