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1.
Nat Microbiol ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698178

RESUMO

The detection of oral bacteria in faecal samples has been associated with inflammation and intestinal diseases. The increased relative abundance of oral bacteria in faeces has two competing explanations: either oral bacteria invade the gut ecosystem and expand (the 'expansion' hypothesis), or oral bacteria transit through the gut and their relative increase marks the depletion of other gut bacteria (the 'marker' hypothesis). Here we collected oral and faecal samples from mouse models of gut dysbiosis (antibiotic treatment and DSS-induced colitis) and used 16S ribosomal RNA sequencing to determine the abundance dynamics of oral bacteria. We found that the relative, but not absolute, abundance of oral bacteria increases, reflecting the 'marker' hypothesis. Faecal microbiome datasets from diverse patient cohorts, including healthy individuals and patients with allogeneic haematopoietic cell transplantation or inflammatory bowel disease, consistently support the 'marker' hypothesis and explain associations between oral bacterial abundance and patient outcomes consistent with depleted gut microbiota. By distinguishing between the two hypotheses, our study guides the interpretation of microbiome compositional data and could potentially identify cases where therapies are needed to rebuild the resident microbiome rather than protect against invading oral bacteria.

2.
ArXiv ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38659636

RESUMO

Fecal Microbiota Transplant (FMT) is an FDA approved treatment for recurrent Clostridium difficile infections, and is being explored for other clinical applications, from alleviating digestive and neurological disorders, to priming the microbiome for cancer treatment, and restoring microbiomes impacted by cancer treatment. Quantifying the extent of engraftment following an FMT is important in determining if a recipient didn't respond because the engrafted microbiome didn't produce the desired outcomes (a successful FMT, but negative treatment outcome), or the microbiome didn't engraft (an unsuccessful FMT and negative treatment outcome). The lack of a consistent methodology for quantifying FMT engraftment extent hinders the assessment of FMT success and its relation to clinical outcomes, and presents challenges for comparing FMT results and protocols across studies. Here we review 46 studies of FMT in humans and model organisms and group their approaches for assessing the extent to which an FMT engrafts into three criteria: 1) Chimeric Asymmetric Community Coalescence investigates microbiome shifts following FMT engraftment using methods such as alpha diversity comparisons, beta diversity comparisons, and microbiome source tracking. 2) Donated Microbiome Indicator Features tracks donated microbiome features (e.g., amplicon sequence variants or species of interest) as a signal of engraftment with methods such as differential abundance testing based on the current sample collection, or tracking changes in feature abundances that have been previously identified (e.g., from FMT or disease-relevant literature). 3) Temporal Stability examines how resistant post-FMT recipient's microbiomes are to reverting back to their baseline microbiome. Individually, these criteria each highlight a critical aspect of microbiome engraftment; investigated together, however, they provide a clearer assessment of microbiome engraftment. We discuss the pros and cons of each of these criteria, providing illustrative examples of their application. We also introduce key terminology and recommendations on how FMT studies can be analyzed for rigorous engraftment extent assessment.

3.
Proc Natl Acad Sci U S A ; 121(11): e2319254121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38442180

RESUMO

Natural killer (NK) cells are a vital part of the innate immune system capable of rapidly clearing mutated or infected cells from the body and promoting an immune response. Here, we find that NK cells activated by viral infection or tumor challenge increase uptake of fatty acids and their expression of carnitine palmitoyltransferase I (CPT1A), a critical enzyme for long-chain fatty acid oxidation. Using a mouse model with an NK cell-specific deletion of CPT1A, combined with stable 13C isotope tracing, we observe reduced mitochondrial function and fatty acid-derived aspartate production in CPT1A-deficient NK cells. Furthermore, CPT1A-deficient NK cells show reduced proliferation after viral infection and diminished protection against cancer due to impaired actin cytoskeleton rearrangement. Together, our findings highlight that fatty acid oxidation promotes NK cell metabolic resilience, processes that can be optimized in NK cell-based immunotherapies.


Assuntos
Neoplasias , Viroses , Humanos , Metabolismo dos Lipídeos , Células Matadoras Naturais , Ácidos Graxos
4.
Facial Plast Surg ; 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38016660

RESUMO

Nasal obstruction (NO) is a common clinical symptom characterized by a subjective sensation of insufficient airflow through the nasal cavity and may result from various factors, including changes in nasal anatomy, inflammatory conditions, tumoral lesions, and other etiologies. While a thorough medical history and physical examination can often identify its cause, imaging is usually necessary to fully understand the problem. Computed tomography (CT) is the primary imaging modality used to evaluate the nasal cavity and paranasal sinuses, allowing for the identification of potential causes and structural abnormalities. However, when soft tissue characterization is required, magnetic resonance imaging (MRI) is also useful. Understanding the anatomical and pathological basis of NO is crucial for accurate diagnosis and appropriate management. Imaging techniques provide valuable information for identifying the underlying causes of NO and guiding treatment decisions. This article reviews the normal anatomy of the nasal cavity and adjacent paranasal sinuses as well as the several conditions that may affect breathing comfort (tumors, inflammatory diseases, bony and cartilaginous anatomical variants, and "nonobstructive" mucosal thickenings), showing their normal presentation on CT and MRI.

5.
Cancer Res ; 83(20): 3478-3491, 2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37526524

RESUMO

Understanding the rewired metabolism underlying organ-specific metastasis in breast cancer could help identify strategies to improve the treatment and prevention of metastatic disease. Here, we used a systems biology approach to compare metabolic fluxes used by parental breast cancer cells and their brain- and lung-homing derivatives. Divergent lineages had distinct, heritable metabolic fluxes. Lung-homing cells maintained high glycolytic flux despite low levels of glycolytic intermediates, constitutively activating a pathway sink into lactate. This strong Warburg effect was associated with a high ratio of lactate dehydrogenase (LDH) to pyruvate dehydrogenase (PDH) expression, which correlated with lung metastasis in patients with breast cancer. Although feature classification models trained on clinical characteristics alone were unable to predict tropism, the LDH/PDH ratio was a significant predictor of metastasis to the lung but not to other organs, independent of other transcriptomic signatures. High lactate efflux was also a trait in lung-homing metastatic pancreatic cancer cells, suggesting that lactate production may be a convergent phenotype in lung metastasis. Together, these analyses highlight the essential role that metabolism plays in organ-specific cancer metastasis and identify a putative biomarker for predicting lung metastasis in patients with breast cancer. SIGNIFICANCE: Lung-homing metastatic breast cancer cells express an elevated ratio of lactate dehydrogenase to pyruvate dehydrogenase, indicating that ratios of specific metabolic gene transcripts have potential as metabolic biomarkers for predicting organ-specific metastasis.


Assuntos
Neoplasias da Mama , Neoplasias Pulmonares , Segunda Neoplasia Primária , Humanos , Feminino , Neoplasias da Mama/patologia , L-Lactato Desidrogenase/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Biomarcadores , Pulmão/patologia , Lactatos , Piruvatos , Melanoma Maligno Cutâneo
6.
bioRxiv ; 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37645838

RESUMO

Metabolic rewiring allows cells to adapt their metabolism in response to evolving environmental conditions. Traditional metabolomics techniques, whether targeted or untargeted, often struggle to interpret these adaptive shifts. Here, we introduce MetaboLiteLearner, a machine learning framework that harnesses the detailed fragmentation patterns from electron ionization (EI) collected in scan mode during gas chromatography/mass spectrometry (GC/MS) to predict abundance changes in metabolically adapted cells. When tested on breast cancer cells with different preferences to metastasize to specific organs, MetaboLiteLearner predicted the impact of metabolic rewiring on metabolites withheld from the training dataset using only the EI spectra, without metabolite identification or pre-existing knowledge of metabolic networks. The model learned captures shared and unique metabolomic shifts between brain- and lung-homing metastatic lineages, suggesting potential organ-tailored cellular adaptations. Integrating machine learning and metabolomics paves the way for new insights into complex cellular adaptations.

7.
Cell ; 186(12): 2705-2718.e17, 2023 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-37295406

RESUMO

Discerning the effect of pharmacological exposures on intestinal bacterial communities in cancer patients is challenging. Here, we deconvoluted the relationship between drug exposures and changes in microbial composition by developing and applying a new computational method, PARADIGM (parameters associated with dynamics of gut microbiota), to a large set of longitudinal fecal microbiome profiles with detailed medication-administration records from patients undergoing allogeneic hematopoietic cell transplantation. We observed that several non-antibiotic drugs, including laxatives, antiemetics, and opioids, are associated with increased Enterococcus relative abundance and decreased alpha diversity. Shotgun metagenomic sequencing further demonstrated subspecies competition, leading to increased dominant-strain genetic convergence during allo-HCT that is significantly associated with antibiotic exposures. We integrated drug-microbiome associations to predict clinical outcomes in two validation cohorts on the basis of drug exposures alone, suggesting that this approach can generate biologically and clinically relevant insights into how pharmacological exposures can perturb or preserve microbiota composition. The application of a computational method called PARADIGM to a large dataset of cancer patients' longitudinal fecal specimens and detailed daily medication records reveals associations between drug exposures and the intestinal microbiota that recapitulate in vitro findings and are also predictive of clinical outcomes.


Assuntos
Microbioma Gastrointestinal , Transplante de Células-Tronco Hematopoéticas , Microbiota , Neoplasias , Humanos , Microbioma Gastrointestinal/genética , Fezes/microbiologia , Metagenoma , Antibacterianos , Neoplasias/tratamento farmacológico
8.
Cell Host Microbe ; 31(7): 1126-1139.e6, 2023 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-37329880

RESUMO

Longitudinal microbiome data provide valuable insight into disease states and clinical responses, but they are challenging to mine and view collectively. To address these limitations, we present TaxUMAP, a taxonomically informed visualization for displaying microbiome states in large clinical microbiome datasets. We used TaxUMAP to chart a microbiome atlas of 1,870 patients with cancer during therapy-induced perturbations. Bacterial density and diversity were positively associated, but the trend was reversed in liquid stool. Low-diversity states (dominations) remained stable after antibiotic treatment, and diverse communities had a broader range of antimicrobial resistance genes than dominations. When examining microbiome states associated with risk for bacteremia, TaxUMAP revealed that certain Klebsiella species were associated with lower risk for bacteremia localize in a region of the atlas that is depleted in high-risk enterobacteria. This indicated a competitive interaction that was validated experimentally. Thus, TaxUMAP can chart comprehensive longitudinal microbiome datasets, enabling insights into microbiome effects on human health.


Assuntos
Bacteriemia , Microbioma Gastrointestinal , Microbiota , Humanos , Microbioma Gastrointestinal/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias/genética
9.
Braz Oral Res ; 37: 025, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37018807

RESUMO

The pandemic caused by coronavirus has resonated throughout different levels of health care in Brazil and, in this context, the present research aimed to evaluate this impact on tertiary dental care provided by the Unified Health System (SUS). Therefore, an ecological study was conducted with data obtained from the Hospital Information System processed by the Portal of the Department of Informatics of SUS. The sample consisted of patients of all sexes and age groups, whose Hospital Admission Authorizations (AIHs) were approved for dental tertiary care procedures from January 2015 to December 2020. Descriptive analyses and the ANOVA test with a significance level set at p < 0.05 were used. When the annual mean numbers of AIHs approved were evaluated, findings showed that on an average, the Southeast region authorized a higher number of procedures (p-value < 0.001), however, in the pandemic year (2020), a reduction of approximately 24.5% of these hospitalizations occurred throughout Brazil, with the Midwest being the region most affected (32.12%). A percentage increase occurred in the Surgical Treatment of Oral sinus/Oral nasal Fistula (16.1%), in addition to a significant decrease in performing procedures for Resection of Mouth Lesion (33.4%). In the pandemic year, there was a reduction of 14% in expenditures related to hospital services and 23.26% related to professional services. It was concluded that the data presented demonstrated a significant reduction in AIHs for tertiary dental care in the pandemic year.


Assuntos
COVID-19 , Humanos , Pandemias , Atenção Terciária à Saúde , Brasil , Assistência Odontológica
10.
Braz. oral res. (Online) ; 37: 025, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS, BBO - Odontologia | ID: biblio-1430037

RESUMO

Abstract The pandemic caused by coronavirus has resonated throughout different levels of health care in Brazil and, in this context, the present research aimed to evaluate this impact on tertiary dental care provided by the Unified Health System (SUS). Therefore, an ecological study was conducted with data obtained from the Hospital Information System processed by the Portal of the Department of Informatics of SUS. The sample consisted of patients of all sexes and age groups, whose Hospital Admission Authorizations (AIHs) were approved for dental tertiary care procedures from January 2015 to December 2020. Descriptive analyses and the ANOVA test with a significance level set at p < 0.05 were used. When the annual mean numbers of AIHs approved were evaluated, findings showed that on an average, the Southeast region authorized a higher number of procedures (p-value < 0.001), however, in the pandemic year (2020), a reduction of approximately 24.5% of these hospitalizations occurred throughout Brazil, with the Midwest being the region most affected (32.12%). A percentage increase occurred in the Surgical Treatment of Oral sinus/Oral nasal Fistula (16.1%), in addition to a significant decrease in performing procedures for Resection of Mouth Lesion (33.4%). In the pandemic year, there was a reduction of 14% in expenditures related to hospital services and 23.26% related to professional services. It was concluded that the data presented demonstrated a significant reduction in AIHs for tertiary dental care in the pandemic year.

11.
Elife ; 112022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36409069

RESUMO

Microbes have disproportionate impacts on the macroscopic world. This is in part due to their ability to grow to large populations that collectively secrete massive amounts of secondary metabolites and alter their environment. Yet, the conditions favoring secondary metabolism despite the potential costs for primary metabolism remain unclear. Here we investigated the biosurfactants that the bacterium Pseudomonas aeruginosa makes and secretes to decrease the surface tension of surrounding liquid. Using a combination of genomics, metabolomics, transcriptomics, and mathematical modeling we show that the ability to make surfactants from glycerol varies inconsistently across the phylogenetic tree; instead, lineages that lost this ability are also worse at reducing the oxidative stress of primary metabolism on glycerol. Experiments with different carbon sources support a link with oxidative stress that explains the inconsistent distribution across the P. aeruginosa phylogeny and suggests a general principle: P. aeruginosa lineages produce surfactants if they can reduce the oxidative stress produced by primary metabolism and have excess resources, beyond their primary needs, to afford secondary metabolism. These results add a new layer to the regulation of a secondary metabolite unessential for primary metabolism but important to change physical properties of the environments surrounding bacterial populations.


Assuntos
Carbono , Glicerol , Metabolismo Secundário , Filogenia , Transporte Biológico , Pseudomonas aeruginosa/genética
12.
Nat Commun ; 13(1): 5617, 2022 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-36153315

RESUMO

Infections by multidrug-resistant Enterobacteriaceae (MRE) are life-threatening to patients. The intestinal microbiome protects against MRE colonization, but antibiotics cause collateral damage to commensals and open the way to colonization and subsequent infection. Despite the significance of this problem, the specific commensals and mechanisms that restrict MRE colonization remain largely unknown. Here, by performing a multi-omic prospective study of hospitalized patients combined with mice experiments, we find that Lactobacillus is key, though not sufficient, to restrict MRE gut colonization. Lactobacillus rhamnosus and murinus increase the levels of Clostridiales bacteria, which induces a hostile environment for MRE growth through increased butyrate levels and reduced nutrient sources. This mechanism of colonization resistance, an interaction between Lactobacillus spp. and Clostridiales involving cooperation between microbiota members, is conserved in mice and patients. These results stress the importance of exploiting microbiome interactions for developing effective probiotics that prevent infections in hospitalized patients.


Assuntos
Enterobacteriaceae , Lactobacillus , Animais , Antibacterianos/farmacologia , Butiratos/farmacologia , Clostridiales , Camundongos , Estudos Prospectivos
13.
GE Port J Gastroenterol ; 29(3): 197-202, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35702174

RESUMO

Introduction: Anorectal pain is a symptom with a negative impact on quality of life and it can sometimes develop into a chronic pain syndrome. Structural anorectal pain is treated according to the underlying pathology. In situations of chronic post-surgical pain that is refractory to conventional therapeutic approaches, percutaneous tibial nerve stimulation (PTNS) is an option. PTNS is a neurostimulation technique used in the treatment of lower urinary tract dysfunction. There has been increasing evidence of its benefits for improving other conditions, such as chronic pelvic pain (CPP) and faecal incontinence (FI). Case Presentation: We report a case of a 45-year-old woman with chronic post-surgical anorectal pain (CPAP) treated with PTNS. The patient reported a consistent and dramatic decrease in both the frequency and intensity of pain, assessed by the Brief Pain Inventory (BPI). A decrease in the pain interference with mood, normal work, and walking/mobility was also noted, as evaluated by BPI and EQ-5D-3L questionnaires. Discussion: Neuromodulation treatments have been reported as effective for anorectal pain, but reports on the use of PTNS are rare. The tibial nerve is easily accessible and provides an optimal site for neurostimulation without the need of an operating room or anaesthesia. The overall improvement observed in this case of chronic anorectal pain suggests a potential new area of research for PTNS.


Introdução: A dor anorectal é um sintoma com um impacto negativo na qualidade de vida, podendo, por vezes, desenvolver-se numa síndrome de dor crónica. A dor ano rectal de etiologia estrutural trata-se de acordo com a patologia subjacente. No entanto, em situações de dor crónica pós-cirúrgica refratária a abordagens terapêuticas convencionais, a estimulação percutânea do nervo tibial (percutaneous tibial nerve stimulation − PTNS) é uma opção de tratamento. A PTNS é uma técnica de neuroestimulação, estando descritos benefícios da sua aplicação no tratamento da urgência, frequência, incontinência e retenção urinária. Evidência crescente mostra, ainda, resultados promissores noutras condições, como a dor crónica pélvica e a incontinência fecal. Caso Clínico: Descrevemos um caso de uma mulher de 45 anos, com dor crónica anorectal pós-cirúrgica tratada com PTNS. Ao longo do período de seguimento, a doente reportou uma diminuição consistente e significativa na frequência e na intensidade da dor, tal como avaliado pelo Brief Pain Inventory (BPI). Adicionalmente, foi notória uma melhoria significativa de parâmetros relacionados com a qualidade de vida, avaliados pelos questionários BPI e EQ-5D-3L. Discussão: A evidência atual mostra que técnicas baseadas em neuromodulação têm sido eficazes no tratamento da dor anorectal, apesar dos estudos com PTNS ainda serem escassos. O nervo tibial é uma estrutura facilmente acessível e constitui um local óptimo para aplicação de neuroestimulação. A PTNS é uma opção terapêutica pouco invasiva, que não necessita de idas ao bloco operatório, nem de apoio de anestesia. O benefício observado do uso da PTNS neste caso sugere uma nova área de estudo e de potencial aplicabilidade para a técnica.

14.
Sci Data ; 9(1): 219, 2022 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-35585088

RESUMO

Hospitalized patients receiving hematopoietic cell transplants provide a unique opportunity to study the human gut microbiome. We previously compiled a large-scale longitudinal dataset of fecal microbiota and associated metadata, but we had limited that analysis to taxonomic composition of bacteria from 16S rRNA gene sequencing. Here we augment those data with shotgun metagenomics. The compilation amounts to a nested subset of 395 samples compiled from different studies at Memorial Sloan Kettering. Shotgun metagenomics describes the microbiome at the functional level, particularly in antimicrobial resistances and virulence factors. We provide accession numbers that link each sample to the paired-end sequencing files deposited in a public repository, which can be directly accessed by the online services of PATRIC to be analyzed without the users having to download or transfer the files. Then, we show how shotgun sequencing enables the assembly of genomes from metagenomic data. The new data, combined with the metadata published previously, enables new functional studies of the microbiomes of patients with cancer receiving bone marrow transplantation.


Assuntos
Fezes , Transplante de Células-Tronco Hematopoéticas , Microbiota , Fezes/microbiologia , Humanos , Metagenômica , Microbiota/genética , RNA Ribossômico 16S/genética
15.
ISME J ; 16(8): 2040-2055, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35597888

RESUMO

Dietary fibers are generally thought to benefit intestinal health. Their impacts on the composition and metabolic function of the gut microbiome, however, vary greatly across individuals. Previous research showed that each individual's response to fibers depends on their baseline gut microbiome, but the ecology driving microbiota remodeling during fiber intake remained unclear. Here, we studied the long-term dynamics of the gut microbiome and short-chain fatty acids (SCFAs) in isogenic mice with distinct microbiota baselines fed with the fermentable fiber inulin and resistant starch compared to the non-fermentable fiber cellulose. We found that inulin produced a generally rapid response followed by gradual stabilization to new equilibria, and those dynamics were baseline-dependent. We parameterized an ecology model from the time-series data, which revealed a group of bacteria whose growth significantly increased in response to inulin and whose baseline abundance and interspecies competition explained the baseline dependence of microbiome density and community composition dynamics. Fecal levels of SCFAs, such as propionate, were associated with the abundance of inulin responders, yet inter-individual variation of gut microbiome impeded the prediction of SCFAs by machine learning models. We showed that our methods and major findings were generalizable to dietary resistant starch. Finally, we analyzed time-series data of synthetic and natural human gut microbiome in response to dietary fiber and validated the inferred interspecies interactions in vitro. This study emphasizes the importance of ecological modeling to understand microbiome responses to dietary changes and the need for personalized interventions.


Assuntos
Microbioma Gastrointestinal , Animais , Fibras na Dieta/metabolismo , Ácidos Graxos Voláteis/metabolismo , Fezes/microbiologia , Humanos , Inulina , Camundongos , Amido Resistente
16.
iScience ; 25(4): 104079, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35359802

RESUMO

Mathematical models have many applications in infectious diseases: epidemiologists use them to forecast outbreaks and design containment strategies; systems biologists use them to study complex processes sustaining pathogens, from the metabolic networks empowering microbial cells to ecological networks in the microbiome that protects its host. Here, we (1) review important models relevant to infectious diseases, (2) draw parallels among models ranging widely in scale. We end by discussing a minimal set of information for a model to promote its use by others and to enable predictions that help us better fight pathogens and the diseases they cause.

17.
Mol Cancer Ther ; 21(5): 831-843, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35247928

RESUMO

Therapeutic resistance is a fundamental obstacle in cancer treatment. Tumors that initially respond to treatment may have a preexisting resistant subclone or acquire resistance during treatment, making relapse theoretically inevitable. Here, we investigate treatment strategies that may delay relapse using mathematical modeling. We find that for a single-drug therapy, pulse treatment-short, elevated doses followed by a complete break from treatment-delays relapse compared with continuous treatment with the same total dose over a length of time. For tumors treated with more than one drug, continuous combination treatment is only sometimes better than sequential treatment, while pulsed combination treatment or simply alternating between the two therapies at defined intervals delays relapse the longest. These results are independent of the fitness cost or benefit of resistance, and are robust to noise. Machine-learning analysis of simulations shows that the initial tumor response and heterogeneity at the start of treatment suffice to determine the benefit of pulsed or alternating treatment strategies over continuous treatment. Analysis of eight tumor burden trajectories of breast cancer patients treated at Memorial Sloan Kettering Cancer Center shows the model can predict time to resistance using initial responses to treatment and estimated preexisting resistant populations. The model calculated that pulse treatment would delay relapse in all eight cases. Overall, our results support that pulsed treatments optimized by mathematical models could delay therapeutic resistance.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos , Recidiva , Carga Tumoral
18.
Trends Cancer ; 8(6): 506-516, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35277375

RESUMO

For decades, mathematical models have influenced how we schedule chemotherapeutics. More recently, mathematical models have leveraged lessons from ecology, evolution, and game theory to advance predictions of optimal treatment schedules, often in a personalized medicine manner. We discuss both established and emerging therapeutic strategies that deviate from canonical standard-of-care regimens, and how mathematical models have contributed to the design of such schedules. We first examine scheduling options for single therapies and review the advantages and disadvantages of various treatment plans. We then consider the challenge of scheduling multiple therapies, and review the mathematical and clinical support for various conflicting treatment schedules. Finally, we propose how a consilience of mathematical and clinical knowledge can best determine the optimal treatment schedules for patients.


Assuntos
Neoplasias , Humanos , Modelos Teóricos , Neoplasias/tratamento farmacológico , Medicina de Precisão
19.
Nat Commun ; 13(1): 721, 2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-35132084

RESUMO

Much of our understanding of bacterial behavior stems from studies in liquid culture. In nature, however, bacteria frequently live in densely packed spatially-structured communities. How does spatial structure affect bacterial cooperative behaviors? In this work, we examine rhamnolipid production-a cooperative and virulent behavior of Pseudomonas aeruginosa. Here we show that, in striking contrast to well-mixed liquid culture, rhamnolipid gene expression in spatially-structured colonies is strongly associated with colony specific growth rate, and is impacted by perturbation with diffusible quorum signals. To interpret these findings, we construct a data-driven statistical inference model which captures a length-scale of bacterial interaction that develops over time. Finally, we find that perturbation of P. aeruginosa swarms with quorum signals preserves the cooperating genotype in competition, rather than creating opportunities for cheaters. Overall, our data demonstrate that the complex response to spatial localization is key to preserving bacterial cooperative behaviors.


Assuntos
Interações Microbianas/fisiologia , Modelos Biológicos , Proteínas de Bactérias/genética , Biomassa , Contagem de Colônia Microbiana , Regulação Bacteriana da Expressão Gênica , Glicolipídeos/genética , Glicolipídeos/metabolismo , Locomoção , Interações Microbianas/genética , Mutação , Imagem Óptica , Regiões Promotoras Genéticas , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/fisiologia , Percepção de Quorum , Análise Espaço-Temporal
20.
J Stroke Cerebrovasc Dis ; 31(4): 106313, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35093627

RESUMO

BACKGROUND AND PURPOSE: Contrary to anterior circulation, the legitimacy of endovascular treatment in posterior circulation stroke is still being questioned. Finding reliable prognostic factors and determining how patient selection should be done has become top priority. METHODS: Observational and retrospective study from two Portuguese hospitals, including all consecutive patients with posterior circulation occlusions who underwent thrombectomy between January 1st 2015 and December 31st 2019. RESULTS: Out of a total of 126 patients, the median age was 74 (IQR 61-80) and 39.7% were female. A good clinical outcome (mRS ≤2) was associated with a lower incidence of coma (24,2% vs 66,7%, p < 0,001) and of sudden onset coma (3% vs 18%,=0,04), a lower NIHSS at admission (14 vs 19, p < 0,001), a higher pc-ASPECTS at admission (10 vs 9, p < 0,001) and at 24 h (8 vs 6, p < 0,001) and a higher BATMAN score (7 vs 6, p = 0,017). Differences in the times of symptom-onset-to-recanalization (496 vs 536, p = 0,19) and symptom-onset-to-coma (130 vs 195, p = 0,52) were not remarkable. When excluding NIHSS and pc-ASPECTS at 24 h, coma (p = 0,003; OR=0,22; 95% CI: 0,08-0,59) and the pc-ASPECTS at admission (p = 0,037; OR=1,63; 95% CI: 1,03-2,57) become independent predictors of good outcome. CONCLUSIONS: In strokes from the posterior circulation, coma, more than time, appears to be an important prognostic factor. The BATMAN and the pc-ASPECTS scores were also associated with clinical outcome and coma.


Assuntos
Procedimentos Endovasculares , Acidente Vascular Cerebral , Idoso , Encéfalo , Coma/diagnóstico , Coma/terapia , Feminino , Humanos , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Trombectomia , Resultado do Tratamento
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