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1.
Mol Cell ; 84(8): 1406-1421.e8, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38490199

RESUMO

Enhancers bind transcription factors, chromatin regulators, and non-coding transcripts to modulate the expression of target genes. Here, we report 3D genome structures of single mouse ES cells as they are induced to exit pluripotency and transition through a formative stage prior to undergoing neuroectodermal differentiation. We find that there is a remarkable reorganization of 3D genome structure where inter-chromosomal intermingling increases dramatically in the formative state. This intermingling is associated with the formation of a large number of multiway hubs that bring together enhancers and promoters with similar chromatin states from typically 5-8 distant chromosomal sites that are often separated by many Mb from each other. In the formative state, genes important for pluripotency exit establish contacts with emerging enhancers within these multiway hubs, suggesting that the structural changes we have observed may play an important role in modulating transcription and establishing new cell identities.


Assuntos
Células-Tronco Embrionárias Murinas , Sequências Reguladoras de Ácido Nucleico , Camundongos , Animais , Células-Tronco Embrionárias Murinas/metabolismo , Células-Tronco Embrionárias/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Cromatina/genética , Cromatina/metabolismo , Elementos Facilitadores Genéticos
2.
Nature ; 616(7957): 581-589, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37020023

RESUMO

General approaches for designing sequence-specific peptide-binding proteins would have wide utility in proteomics and synthetic biology. However, designing peptide-binding proteins is challenging, as most peptides do not have defined structures in isolation, and hydrogen bonds must be made to the buried polar groups in the peptide backbone1-3. Here, inspired by natural and re-engineered protein-peptide systems4-11, we set out to design proteins made out of repeating units that bind peptides with repeating sequences, with a one-to-one correspondence between the repeat units of the protein and those of the peptide. We use geometric hashing to identify protein backbones and peptide-docking arrangements that are compatible with bidentate hydrogen bonds between the side chains of the protein and the peptide backbone12. The remainder of the protein sequence is then optimized for folding and peptide binding. We design repeat proteins to bind to six different tripeptide-repeat sequences in polyproline II conformations. The proteins are hyperstable and bind to four to six tandem repeats of their tripeptide targets with nanomolar to picomolar affinities in vitro and in living cells. Crystal structures reveal repeating interactions between protein and peptide interactions as designed, including ladders of hydrogen bonds from protein side chains to peptide backbones. By redesigning the binding interfaces of individual repeat units, specificity can be achieved for non-repeating peptide sequences and for disordered regions of native proteins.


Assuntos
Peptídeos , Engenharia de Proteínas , Proteínas , Sequência de Aminoácidos , Modelos Moleculares , Peptídeos/química , Peptídeos/metabolismo , Proteínas/química , Proteínas/metabolismo , Engenharia de Proteínas/métodos , Ligação de Hidrogênio , Ligação Proteica , Dobramento de Proteína , Conformação Proteica
3.
Nature ; 609(7926): 313-319, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36045297

RESUMO

The vertebrate lineages that would shape Mesozoic and Cenozoic terrestrial ecosystems originated across Triassic Pangaea1-11. By the Late Triassic (Carnian stage, ~235 million years ago), cosmopolitan 'disaster faunas' (refs. 12-14) had given way to highly endemic assemblages12,13 on the supercontinent. Testing the tempo and mode of the establishment of this endemism is challenging-there were few geographic barriers to dispersal across Pangaea during the Late Triassic. Instead, palaeolatitudinal climate belts, and not continental boundaries, are proposed to have controlled distribution15-18. During this time of high endemism, dinosaurs began to disperse and thus offer an opportunity to test the timing and drivers of this biogeographic pattern. Increased sampling can test this prediction: if dinosaurs initially dispersed under palaeolatitudinal-driven endemism, then an assemblage similar to those of South America4,19-21 and India19,22-including the earliest dinosaurs-should be present in Carnian deposits in south-central Africa. Here we report a new Carnian assemblage from Zimbabwe that includes Africa's oldest definitive dinosaurs, including a nearly complete skeleton of the sauropodomorph Mbiresaurus raathi gen. et sp. nov. This assemblage resembles other dinosaur-bearing Carnian assemblages, suggesting that a similar vertebrate fauna ranged high-latitude austral Pangaea. The distribution of the first dinosaurs is correlated with palaeolatitude-linked climatic barriers, and dinosaurian dispersal to the rest of the supercontinent was delayed until these barriers relaxed, suggesting that climatic controls influenced the initial composition of the terrestrial faunas that persist to this day.


Assuntos
Dinossauros , Ecossistema , Animais , Clima , Fósseis , História Antiga , Filogenia , Filogeografia , Densidade Demográfica , Dinâmica Populacional , Esqueleto , Zimbábue
4.
Development ; 151(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38205939

RESUMO

Asymmetric cell divisions often generate daughter cells of unequal size in addition to different fates. In some contexts, daughter cell size asymmetry is thought to be a key input to specific binary cell fate decisions. An alternative possibility is that unequal division is a mechanism by which a variety of cells of different sizes are generated during embryonic development. We show here that two unequal cell divisions precede neuroblast formation in the C lineage of Caenorhabditis elegans. The equalisation of these divisions in a pig-1/MELK mutant background has little effect on neuroblast specification. Instead, we demonstrate that let-19/MDT13 is a regulator of the proneural basic helix-loop-helix transcription factor hlh-14/ASCL1 and find that both are required to concomitantly regulate the acquisition of neuroblast identity and neuroblast cell size. Thus, embryonic neuroblast cell size in this lineage is progressively regulated in parallel with identity by key neural cell fate regulators. We propose that key cell fate determinants have a previously unappreciated function in regulating unequal cleavage, and therefore cell size, of the progenitor cells whose daughter cell fates they then go on to specify.


Assuntos
Proteínas de Caenorhabditis elegans , Células-Tronco Neurais , Animais , Proteínas de Caenorhabditis elegans/genética , Neurônios , Caenorhabditis elegans , Divisão Celular , Tamanho Celular
5.
Proc Natl Acad Sci U S A ; 121(38): e2410679121, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39264739

RESUMO

Enterotoxigenic Escherichia coli (ETEC) cause hundreds of millions of diarrheal illnesses annually ranging from mildly symptomatic cases to severe, life-threatening cholera-like diarrhea. Although ETEC are associated with long-term sequelae including malnutrition, the acute diarrheal illness is largely self-limited. Recent studies indicate that in addition to causing diarrhea, the ETEC heat-labile toxin (LT) modulates the expression of many genes in intestinal epithelia, including carcinoembryonic cell adhesion molecules (CEACAMs) which ETEC exploit as receptors, enabling toxin delivery. Here, however, we demonstrate that LT also enhances the expression of CEACAMs on extracellular vesicles (EV) shed by intestinal epithelia and that CEACAM-laden EV increase in abundance during human infections, mitigate pathogen-host interactions, scavenge free ETEC toxins, and accelerate ETEC clearance from the gastrointestinal tract. Collectively, these findings indicate that CEACAMs play a multifaceted role in ETEC pathogen-host interactions, transiently favoring the pathogen, but ultimately contributing to innate responses that extinguish these common infections.


Assuntos
Toxinas Bacterianas , Escherichia coli Enterotoxigênica , Enterotoxinas , Infecções por Escherichia coli , Proteínas de Escherichia coli , Interações Hospedeiro-Patógeno , Escherichia coli Enterotoxigênica/metabolismo , Humanos , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Enterotoxinas/metabolismo , Toxinas Bacterianas/metabolismo , Vesículas Extracelulares/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Animais , Camundongos , Antígenos CD/metabolismo , Antígenos CD/genética , Antígeno Carcinoembrionário/metabolismo , Antígeno Carcinoembrionário/genética , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular/genética , Diarreia/microbiologia , Diarreia/metabolismo
6.
J Cell Sci ; 137(11)2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38864427

RESUMO

Endocannabinoid signalling mediated by cannabinoid receptor 1 (CB1R, also known as CNR1) is critical for homeostatic neuromodulation of both excitatory and inhibitory synapses. This requires highly polarised axonal surface expression of CB1R, but how this is achieved remains unclear. We previously reported that the α-helical H9 domain in the intracellular C terminus of CB1R contributes to axonal surface expression by an unknown mechanism. Here, we show in rat primary neuronal cultures that the H9 domain binds to the endocytic adaptor protein SGIP1 to promote CB1R expression in the axonal membrane. Overexpression of SGIP1 increases CB1R axonal surface localisation but has no effect on CB1R lacking the H9 domain (CB1RΔH9). Conversely, SGIP1 knockdown reduces axonal surface expression of CB1R but does not affect CB1RΔH9. Furthermore, SGIP1 knockdown diminishes CB1R-mediated inhibition of presynaptic Ca2+ influx in response to neuronal activity. Taken together, these data advance mechanistic understanding of endocannabinoid signalling by demonstrating that SGIP1 interaction with the H9 domain underpins axonal CB1R surface expression to regulate presynaptic responsiveness.


Assuntos
Axônios , Ligação Proteica , Receptor CB1 de Canabinoide , Animais , Receptor CB1 de Canabinoide/metabolismo , Receptor CB1 de Canabinoide/genética , Axônios/metabolismo , Ratos , Domínios Proteicos , Humanos , Células Cultivadas , Neurônios/metabolismo , Ratos Sprague-Dawley , Membrana Celular/metabolismo
7.
N Engl J Med ; 388(17): 1547-1558, 2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-36912538

RESUMO

BACKGROUND: Between 1999 and 2009 in the United Kingdom, 82,429 men between 50 and 69 years of age received a prostate-specific antigen (PSA) test. Localized prostate cancer was diagnosed in 2664 men. Of these men, 1643 were enrolled in a trial to evaluate the effectiveness of treatments, with 545 randomly assigned to receive active monitoring, 553 to undergo prostatectomy, and 545 to undergo radiotherapy. METHODS: At a median follow-up of 15 years (range, 11 to 21), we compared the results in this population with respect to death from prostate cancer (the primary outcome) and death from any cause, metastases, disease progression, and initiation of long-term androgen-deprivation therapy (secondary outcomes). RESULTS: Follow-up was complete for 1610 patients (98%). A risk-stratification analysis showed that more than one third of the men had intermediate or high-risk disease at diagnosis. Death from prostate cancer occurred in 45 men (2.7%): 17 (3.1%) in the active-monitoring group, 12 (2.2%) in the prostatectomy group, and 16 (2.9%) in the radiotherapy group (P = 0.53 for the overall comparison). Death from any cause occurred in 356 men (21.7%), with similar numbers in all three groups. Metastases developed in 51 men (9.4%) in the active-monitoring group, in 26 (4.7%) in the prostatectomy group, and in 27 (5.0%) in the radiotherapy group. Long-term androgen-deprivation therapy was initiated in 69 men (12.7%), 40 (7.2%), and 42 (7.7%), respectively; clinical progression occurred in 141 men (25.9%), 58 (10.5%), and 60 (11.0%), respectively. In the active-monitoring group, 133 men (24.4%) were alive without any prostate cancer treatment at the end of follow-up. No differential effects on cancer-specific mortality were noted in relation to the baseline PSA level, tumor stage or grade, or risk-stratification score. No treatment complications were reported after the 10-year analysis. CONCLUSIONS: After 15 years of follow-up, prostate cancer-specific mortality was low regardless of the treatment assigned. Thus, the choice of therapy involves weighing trade-offs between benefits and harms associated with treatments for localized prostate cancer. (Funded by the National Institute for Health and Care Research; ProtecT Current Controlled Trials number, ISRCTN20141297; ClinicalTrials.gov number, NCT02044172.).


Assuntos
Antígeno Prostático Específico , Neoplasias da Próstata , Humanos , Masculino , Antagonistas de Androgênios/uso terapêutico , Androgênios , Seguimentos , Antígeno Prostático Específico/sangue , Prostatectomia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/terapia , Conduta Expectante , Pessoa de Meia-Idade , Idoso , Radioterapia , Medição de Risco
8.
Development ; 150(7)2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36897564

RESUMO

During morphogenesis, large-scale changes of tissue primordia are coordinated across an embryo. In Drosophila, several tissue primordia and embryonic regions are bordered or encircled by supracellular actomyosin cables, junctional actomyosin enrichments networked between many neighbouring cells. We show that the single Drosophila Alp/Enigma-family protein Zasp52, which is most prominently found in Z-discs of muscles, is a component of many supracellular actomyosin structures during embryogenesis, including the ventral midline and the boundary of the salivary gland placode. We reveal that Zasp52 contains within its central coiled-coil region a type of actin-binding motif usually found in CapZbeta proteins, and this domain displays actin-binding activity. Using endogenously-tagged lines, we identify that Zasp52 interacts with junctional components, including APC2, Polychaetoid and Sidekick, and actomyosin regulators. Analysis of zasp52 mutant embryos reveals that the severity of the embryonic defects observed scales inversely with the amount of functional protein left. Large tissue deformations occur where actomyosin cables are found during embryogenesis, and in vivo and in silico analyses suggest a model whereby supracellular Zasp52-containing cables aid to insulate morphogenetic changes from one another.


Assuntos
Actomiosina , Proteínas de Drosophila , Animais , Actomiosina/metabolismo , Actinas/metabolismo , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/metabolismo , Sarcômeros/metabolismo , Morfogênese/genética
9.
PLoS Pathog ; 20(9): e1012241, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39283948

RESUMO

Enterotoxigenic Escherichia coli (ETEC) cause hundreds of millions of cases of infectious diarrhea annually, predominantly in children from low-middle income regions. Notably, in children, as well as volunteers challenged with ETEC, diarrheal severity is significantly increased in blood group A (bgA) individuals. EtpA, is a secreted glycoprotein adhesin that functions as a blood group A lectin to promote critical interactions between ETEC and blood group A glycans on intestinal epithelia for effective bacterial adhesion and toxin delivery. EtpA is highly immunogenic resulting in robust antibody responses following natural infection and experimental challenge of volunteers with ETEC. To understand how EtpA directs ETEC-blood group A interactions and stimulates adaptive immunity, we mutated EtpA, mapped its glycosylation by mass-spectrometry (MS), isolated polyclonal (pAbs) and monoclonal antibodies (mAbs) from vaccinated mice and ETEC-infected volunteers, and determined structures of antibody-EtpA complexes by cryo-electron microscopy. Both bgA and mAbs that inhibited EtpA-bgA interactions and ETEC adhesion, bound to the C-terminal repeat domain highlighting this region as crucial for ETEC pathogen-host interaction. MS analysis uncovered extensive and heterogeneous N-linked glycosylation of EtpA and cryo-EM structures revealed that mAbs directly engage these unique glycan containing epitopes. Finally, electron microscopy-based polyclonal epitope mapping revealed antibodies targeting numerous distinct epitopes on N and C-terminal domains, suggesting that EtpA vaccination generates responses against neutralizing and decoy regions of the molecule. Collectively, we anticipate that these data will inform our general understanding of pathogen-host glycan interactions and adaptive immunity relevant to rational vaccine subunit design.


Assuntos
Escherichia coli Enterotoxigênica , Infecções por Escherichia coli , Proteínas de Escherichia coli , Polissacarídeos , Escherichia coli Enterotoxigênica/imunologia , Camundongos , Animais , Polissacarídeos/imunologia , Polissacarídeos/metabolismo , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/microbiologia , Humanos , Proteínas de Escherichia coli/imunologia , Glicosilação , Adesinas de Escherichia coli/imunologia , Adesinas de Escherichia coli/metabolismo , Anticorpos Antibacterianos/imunologia , Aderência Bacteriana/imunologia , Glicoproteínas de Membrana
10.
PLoS Biol ; 21(8): e3002222, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37552676

RESUMO

The human genome encodes approximately 20,000 proteins, many still uncharacterised. It has become clear that scientific research tends to focus on well-studied proteins, leading to a concern that poorly understood genes are unjustifiably neglected. To address this, we have developed a publicly available and customisable "Unknome database" that ranks proteins based on how little is known about them. We applied RNA interference (RNAi) in Drosophila to 260 unknown genes that are conserved between flies and humans. Knockdown of some genes resulted in loss of viability, and functional screening of the rest revealed hits for fertility, development, locomotion, protein quality control, and resilience to stress. CRISPR/Cas9 gene disruption validated a component of Notch signalling and 2 genes contributing to male fertility. Our work illustrates the importance of poorly understood genes, provides a resource to accelerate future research, and highlights a need to support database curation to ensure that misannotation does not erode our awareness of our own ignorance.


Assuntos
Drosophila , Fertilidade , Animais , Masculino , Humanos , Drosophila/genética , Interferência de RNA , Fertilidade/genética
11.
Development ; 149(3)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35005771

RESUMO

Zebrafish transgenic lines and light sheet fluorescence microscopy allow in-depth insights into three-dimensional vascular development in vivo. However, quantification of the zebrafish cerebral vasculature in 3D remains highly challenging. Here, we describe and test an image analysis workflow for 3D quantification of the total or regional zebrafish brain vasculature, called zebrafish vasculature quantification (ZVQ). It provides the first landmark- or object-based vascular inter-sample registration of the zebrafish cerebral vasculature, producing population average maps allowing rapid assessment of intra- and inter-group vascular anatomy. ZVQ also extracts a range of quantitative vascular parameters from a user-specified region of interest, including volume, surface area, density, branching points, length, radius and complexity. Application of ZVQ to 13 experimental conditions, including embryonic development, pharmacological manipulations and morpholino-induced gene knockdown, shows that ZVQ is robust, allows extraction of biologically relevant information and quantification of vascular alteration, and can provide novel insights into vascular biology. To allow dissemination, the code for quantification, a graphical user interface and workflow documentation are provided. Together, ZVQ provides the first open-source quantitative approach to assess the 3D cerebrovascular architecture in zebrafish.


Assuntos
Veias Cerebrais/diagnóstico por imagem , Imageamento Tridimensional/métodos , Peixe-Zebra/crescimento & desenvolvimento , Animais , Animais Geneticamente Modificados/crescimento & desenvolvimento , Automação , Encéfalo/irrigação sanguínea , Análise por Conglomerados , Embrião não Mamífero/irrigação sanguínea , Desenvolvimento Embrionário , Processamento de Imagem Assistida por Computador , Interface Usuário-Computador
12.
Cell ; 142(1): 158-69, 2010 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-20603021

RESUMO

The various membranes of eukaryotic cells differ in composition, but it is at present unclear if this results in differences in physical properties. The sequences of transmembrane domains (TMDs) of integral membrane proteins should reflect the physical properties of the bilayers in which they reside. We used large datasets from both fungi and vertebrates to perform a comprehensive comparison of the TMDs of proteins from different organelles. We find that TMDs are not generic but have organelle-specific properties with a dichotomy in TMD length between the early and late parts of the secretory pathway. In addition, TMDs from post-ER organelles show striking asymmetries in amino acid compositions across the bilayer that is linked to residue size and varies between organelles. The pervasive presence of organelle-specific features among the TMDs of a particular organelle has implications for TMD prediction, regulation of protein activity by location, and sorting of proteins and lipids in the secretory pathway.


Assuntos
Proteínas de Membrana/química , Estrutura Terciária de Proteína , Homologia Estrutural de Proteína , Animais , Membrana Celular/metabolismo , Complexo de Golgi/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Proteínas de Membrana/metabolismo , Organelas/metabolismo
13.
Proc Natl Acad Sci U S A ; 119(5)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35082153

RESUMO

The regeneration of bioavailable phosphate from immobilized organophosphorus represents a key process in the global phosphorus cycle and is facilitated by enzymes known as phosphatases. Most bacteria possess at least one of three phosphatases with broad substrate specificity, known as PhoA, PhoX, and PhoD, whose activity is optimal under alkaline conditions. The production and activity of these phosphatases is repressed by phosphate availability. Therefore, they are only fully functional when bacteria experience phosphorus-limiting growth conditions. Here, we reveal a previously overlooked phosphate-insensitive phosphatase, PafA, prevalent in Bacteroidetes, which is highly abundant in nature and represents a major route for the regeneration of environmental phosphate. Using the enzyme from Flavobacterium johnsoniae, we show that PafA is highly active toward phosphomonoesters, is fully functional in the presence of excess phosphate, and is essential for growth on phosphorylated carbohydrates as a sole carbon source. These distinct properties of PafA may expand the metabolic niche of Bacteroidetes by enabling the utilization of abundant organophosphorus substrates as C and P sources, providing a competitive advantage when inhabiting zones of high microbial activity and nutrient demand. PafA, which is constitutively synthesized by soil and marine flavobacteria, rapidly remineralizes phosphomonoesters releasing bioavailable phosphate that can be acquired by neighboring cells. The pafA gene is highly diverse in plant rhizospheres and is abundant in the global ocean, where it is expressed independently of phosphate availability. PafA therefore represents an important enzyme in the context of global biogeochemical cycling and has potential applications in sustainable agriculture.


Assuntos
Proteínas de Bactérias/metabolismo , Fosfatos/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Fósforo/metabolismo , Bacteroidetes/metabolismo , Biodiversidade , Flavobacterium/metabolismo
14.
Proc Natl Acad Sci U S A ; 119(28): e2123212119, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35867757

RESUMO

Humans lack the capacity to produce the Galα1-3Galß1-4GlcNAc (α-gal) glycan, and produce anti-α-gal antibodies upon exposure to the carbohydrate on a diverse set of immunogens, including commensal gut bacteria, malaria parasites, cetuximab, and tick proteins. Here we use X-ray crystallographic analysis of antibodies from α-gal knockout mice and humans in complex with the glycan to reveal a common binding motif, centered on a germline-encoded tryptophan residue at Kabat position 33 (W33) of the complementarity-determining region of the variable heavy chain (CDRH1). Immunoglobulin sequencing of anti-α-gal B cells in healthy humans and tick-induced mammalian meat anaphylaxis patients revealed preferential use of heavy chain germline IGHV3-7, encoding W33, among an otherwise highly polyclonal antibody response. Antigen binding was critically dependent on the presence of the germline-encoded W33 residue for all of the analyzed antibodies; moreover, introduction of the W33 motif into naive IGHV3-23 antibody phage libraries enabled the rapid selection of α-gal binders. Our results outline structural and genetic factors that shape the human anti-α-galactosyl antibody response, and provide a framework for future therapeutics development.


Assuntos
Anafilaxia , Anticorpos , Hipersensibilidade Alimentar , Cadeias Pesadas de Imunoglobulinas , Região Variável de Imunoglobulina , Doenças Transmitidas por Carrapatos , Trissacarídeos , Anafilaxia/imunologia , Animais , Anticorpos/química , Anticorpos/genética , Formação de Anticorpos/genética , Complexo Antígeno-Anticorpo/química , Cristalografia por Raios X , Hipersensibilidade Alimentar/imunologia , Humanos , Cadeias Pesadas de Imunoglobulinas/química , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/química , Região Variável de Imunoglobulina/imunologia , Camundongos , Camundongos Knockout , Biblioteca de Peptídeos , Conformação Proteica , Doenças Transmitidas por Carrapatos/imunologia , Trissacarídeos/genética , Trissacarídeos/imunologia
15.
Gut ; 73(10): 1650-1661, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-38955400

RESUMO

OBJECTIVE: Gut microbiome composition is associated with multiple diseases, but relatively little is known about its relationship with long-term outcome measures. While gut dysbiosis has been linked to mortality risk in the general population, the relationship with overall survival in specific diseases has not been extensively studied. In the current study, we present results from an in-depth analysis of the relationship between gut dysbiosis and all-cause and cause-specific mortality in the setting of solid organ transplant recipients (SOTR). DESIGN: We analysed 1337 metagenomes derived from faecal samples of 766 kidney, 334 liver, 170 lung and 67 heart transplant recipients part of the TransplantLines Biobank and Cohort-a prospective cohort study including extensive phenotype data with 6.5 years of follow-up. To analyze gut dysbiosis, we included an additional 8208 metagenomes from the general population of the same geographical area (northern Netherlands). Multivariable Cox regression and a machine learning algorithm were used to analyse the association between multiple indicators of gut dysbiosis, including individual species abundances, and all-cause and cause-specific mortality. RESULTS: We identified two patterns representing overall microbiome community variation that were associated with both all-cause and cause-specific mortality. The gut microbiome distance between each transplantation recipient to the average of the general population was associated with all-cause mortality and death from infection, malignancy and cardiovascular disease. A multivariable Cox regression on individual species abundances identified 23 bacterial species that were associated with all-cause mortality, and by applying a machine learning algorithm, we identified a balance (a type of log-ratio) consisting of 19 out of the 23 species that were associated with all-cause mortality. CONCLUSION: Gut dysbiosis is consistently associated with mortality in SOTR. Our results support the observations that gut dysbiosis is associated with long-term survival. Since our data do not allow us to infer causality, more preclinical research is needed to understand mechanisms before we can determine whether gut microbiome-directed therapies may be designed to improve long-term outcomes.


Assuntos
Disbiose , Microbioma Gastrointestinal , Transplante de Órgãos , Humanos , Disbiose/mortalidade , Feminino , Masculino , Pessoa de Meia-Idade , Transplante de Órgãos/efeitos adversos , Estudos Prospectivos , Causas de Morte , Transplantados/estatística & dados numéricos , Adulto , Fezes/microbiologia , Países Baixos/epidemiologia , Metagenoma , Idoso
16.
Br J Cancer ; 130(1): 9-18, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37898721

RESUMO

Adenocarcinoma of the oesophagus and gastro-oesophageal junction represent a large burden of cancer death in the Western World with an increasing incidence. In the past two decades, the overall survival of patients on a potentially curative treatment pathway has more than doubled due to the addition of perioperative oncological therapies to surgery. However, patients often fail to respond to oncological treatment or struggle to complete their treatment after surgery. In this review, we discuss the current evidence for total neoadjuvant therapy and options for assessment of treatment response.


Assuntos
Adenocarcinoma , Neoplasias Esofágicas , Humanos , Terapia Neoadjuvante , Neoplasias Esofágicas/tratamento farmacológico , Adenocarcinoma/tratamento farmacológico , Junção Esofagogástrica
17.
Br J Cancer ; 130(10): 1697-1708, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38499728

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) incidence has increased rapidly, and prognosis remains poor. We aimed to explore predictors of routes to diagnosis (RtD), and outcomes, in HCC cases. METHODS: HCC cases diagnosed 2006-2017 were identified from the National Cancer Registration Dataset and linked to Hospital Episode Statistics and the RtD metric. Multivariable logistic regression was used to explore associations between RtD, diagnosis year, 365-day mortality and receipt of potentially curative treatment. RESULTS: 23,555 HCC cases were identified; 36.1% via emergency presentation (EP), 30.2% GP referral (GP), 17.1% outpatient referral, 11.0% two-week wait and 4.6% other/unknown routes. Odds of 365-day mortality was >70% lower via GP or OP routes than EP, and odds of curative treatment 3-4 times higher. Further adjustment for cancer/cirrhosis stage attenuated the associations with curative treatment. People who were older, female, had alcohol-related liver disease, or were more deprived, were at increased risk of an EP. Over time, diagnoses via EP decreased, and via GP increased. CONCLUSIONS: HCC RtD is an important predictor of outcomes. Continuing to reduce EP and increase GP and OP presentations, for example by identifying and regularly monitoring patients at higher risk of HCC, may improve stage at diagnosis and survival.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/epidemiologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/epidemiologia , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Adulto , Encaminhamento e Consulta/estatística & dados numéricos , Prognóstico , Idoso de 80 Anos ou mais , Adulto Jovem , Adolescente
18.
Am J Transplant ; 24(8): 1456-1466, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38493925

RESUMO

Kidney transplant recipients (KTRs) experience more fatigue, anxiety, and depressive symptoms and lower concentration and health-related quality of life (HRQoL) compared with the general population. Anemia is a potential cause that is well-recognized and treated. Iron deficiency, however, is often unrecognized, despite its potential detrimental effects related to and unrelated to anemia. We investigated the interplay of anemia, iron deficiency, and patient-reported outcomes in 814 outpatient KTRs (62% male, age 56 ± 13 years) enrolled in the TransplantLines Biobank and Cohort Study (Groningen, The Netherlands). In total, 28% had iron deficiency (ie, transferrin saturation < 20% and ferritin < 100 µg/L), and 29% had anemia (World Health Organization criteria). In linear regression analyses, iron deficiency, but not anemia, was associated with more fatigue, worse concentration, lower wellbeing, more anxiety, more depressive symptoms, and lower HRQoL, independent of age, sex, estimated glomerular filtration rate, anemia, and other potential confounders. In the fully adjusted logistic regression models, iron deficiency was associated with an estimated 53% higher risk of severe fatigue, a 100% higher risk of major depressive symptoms, and a 51% higher chance of being at risk for sick leave/work disability. Clinical trials are needed to investigate the effect of iron deficiency correction on patient-reported outcomes and HRQoL in KTRs.


Assuntos
Transplante de Rim , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Seguimentos , Prognóstico , Falência Renal Crônica/cirurgia , Taxa de Filtração Glomerular , Transplantados/psicologia , Fatores de Risco , Anemia , Deficiências de Ferro , Anemia Ferropriva , Depressão/etiologia , Adulto , Testes de Função Renal , Fadiga/etiologia , Complicações Pós-Operatórias , Países Baixos , Idoso , Ansiedade/etiologia
19.
Microbiology (Reading) ; 170(8)2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39106481

RESUMO

The rhizosphere hosts complex and abundant microbiomes whose structure and composition are now well described by metagenomic studies. However, the dynamic mechanisms that enable micro-organisms to establish along a growing plant root are poorly characterized. Here, we studied how a motile bacterium utilizes the microhabitats created by soil pore space to establish in the proximity of plant roots. We have established a model system consisting of Bacillus subtilis and lettuce seedlings co-inoculated in transparent soil microcosms. We carried out live imaging experiments and developed image analysis pipelines to quantify the abundance of the bacterium as a function of time and position in the pore space. Results showed that the establishment of the bacterium in the rhizosphere follows a precise sequence of events where small islands of mobile bacteria were first seen forming near the root tip within the first 12-24 h of inoculation. Biofilm was then seen forming on the root epidermis at distances of about 700-1000 µm from the tip. Bacteria accumulated predominantly in confined pore spaces within 200 µm from the root or the surface of a particle. Using probabilistic models, we could map the complete sequence of events and propose a conceptual model of bacterial establishment in the pore space. This study therefore advances our understanding of the respective role of growth and mobility in the efficient colonization of bacteria in the rhizosphere.


Assuntos
Bacillus subtilis , Lactuca , Raízes de Plantas , Rizosfera , Microbiologia do Solo , Bacillus subtilis/crescimento & desenvolvimento , Bacillus subtilis/metabolismo , Bacillus subtilis/fisiologia , Raízes de Plantas/microbiologia , Lactuca/microbiologia , Biofilmes/crescimento & desenvolvimento , Plântula/microbiologia , Plântula/crescimento & desenvolvimento
20.
Breast Cancer Res Treat ; 203(3): 523-531, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37882921

RESUMO

PURPOSE: This observational study aims to assess the feasibility of calculating indicators developed by the European Commission Initiative on Breast Cancer (ECIBC) for the Dutch breast cancer population. METHODS: Patients diagnosed with invasive or in situ breast cancer between 2012 and 2018 were selected from the Netherlands Cancer Registry (NCR). Outcomes of the quality indicators (QI) were presented as mean scores and were compared to a stated norm. Variation between hospitals was assessed by standard deviations and funnel plots and trends over time were evaluated. The quality indicator calculator (QIC) was validated by comparing these outcomes with the outcomes of constructed algorithms in Stata. RESULTS: In total, 133,527 patients were included. Data for 24 out of 26 QIs were available in the NCR. For 67% and 67% of the QIs, a mean score above the norm and low or medium hospital variation was observed, respectively. The proportion of patients undergoing a breast reconstruction or neoadjuvant systemic therapy increased over time. The proportion treated within 4 weeks from diagnosis, having >10 lymph nodes removed or estrogen negative breast cancer who underwent adjuvant chemotherapy decreased. The outcomes of the constructed algorithms in this study and the QIC showed 100% similarity. CONCLUSION: Data from the NCR could be used for the calculation of more than 92% of the ECIBC indicators. The quality of breast cancer care in the Netherlands is high, as more than half of the QIs already score above the norm and medium hospital variation was observed. The QIC can be easy and reliably applied.


Assuntos
Carcinoma de Mama in situ , Neoplasias da Mama , Humanos , Feminino , Indicadores de Qualidade em Assistência à Saúde , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/terapia , Países Baixos/epidemiologia , Hospitais
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