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1.
Cell ; 171(5): 1042-1056.e10, 2017 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-29056344

RESUMO

We present an extensive assessment of mutation burden through sequencing analysis of >81,000 tumors from pediatric and adult patients, including tumors with hypermutation caused by chemotherapy, carcinogens, or germline alterations. Hypermutation was detected in tumor types not previously associated with high mutation burden. Replication repair deficiency was a major contributing factor. We uncovered new driver mutations in the replication-repair-associated DNA polymerases and a distinct impact of microsatellite instability and replication repair deficiency on the scale of mutation load. Unbiased clustering, based on mutational context, revealed clinically relevant subgroups regardless of the tumors' tissue of origin, highlighting similarities in evolutionary dynamics leading to hypermutation. Mutagens, such as UV light, were implicated in unexpected cancers, including sarcomas and lung tumors. The order of mutational signatures identified previous treatment and germline replication repair deficiency, which improved management of patients and families. These data will inform tumor classification, genetic testing, and clinical trial design.


Assuntos
Neoplasias/genética , Adulto , Criança , Análise por Conglomerados , DNA Polimerase II/genética , DNA Polimerase III/genética , Replicação do DNA , Humanos , Mutação , Neoplasias/classificação , Neoplasias/patologia , Neoplasias/terapia , Proteínas de Ligação a Poli-ADP-Ribose/genética
2.
Nature ; 623(7988): 757-764, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37968390

RESUMO

Extreme weather events perturb ecosystems and increasingly threaten biodiversity1. Ecologists emphasize the need to forecast and mitigate the impacts of these events, which requires knowledge of how risk is distributed among species and environments. However, the scale and unpredictability of extreme events complicate risk assessment1-4-especially for large animals (megafauna), which are ecologically important and disproportionately threatened but are wide-ranging and difficult to monitor5. Traits such as body size, dispersal ability and habitat affiliation are hypothesized to determine the vulnerability of animals to natural hazards1,6,7. Yet it has rarely been possible to test these hypotheses or, more generally, to link the short-term and long-term ecological effects of weather-related disturbance8,9. Here we show how large herbivores and carnivores in Mozambique responded to Intense Tropical Cyclone Idai, the deadliest storm on record in Africa, across scales ranging from individual decisions in the hours after landfall to changes in community composition nearly 2 years later. Animals responded behaviourally to rising floodwaters by moving upslope and shifting their diets. Body size and habitat association independently predicted population-level impacts: five of the smallest and most lowland-affiliated herbivore species declined by an average of 28% in the 20 months after landfall, while four of the largest and most upland-affiliated species increased by an average of 26%. We attribute the sensitivity of small-bodied species to their limited mobility and physiological constraints, which restricted their ability to avoid the flood and endure subsequent reductions in the quantity and quality of food. Our results identify general traits that govern animal responses to severe weather, which may help to inform wildlife conservation in a volatile climate.


Assuntos
Tamanho Corporal , Tempestades Ciclônicas , Mamíferos , Animais , Altitude , Biodiversidade , Carnivoridade , Conservação dos Recursos Naturais , Dieta/veterinária , Ecossistema , Clima Extremo , Inundações , Previsões , Herbivoria , Mamíferos/anatomia & histologia , Mamíferos/fisiologia , Moçambique
3.
N Engl J Med ; 388(1): 44-54, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36546659

RESUMO

BACKGROUND: Adagrasib, an oral small-molecule inhibitor of mutant KRAS G12C protein, has shown clinical activity in pretreated patients with several tumor types, including colorectal cancer. Preclinical studies suggest that combining a KRAS G12C inhibitor with an epidermal growth factor receptor antibody could be an effective clinical strategy. METHODS: In this phase 1-2, open-label, nonrandomized clinical trial, we assigned heavily pretreated patients with metastatic colorectal cancer with mutant KRAS G12C to receive adagrasib monotherapy (600 mg orally twice daily) or adagrasib (at the same dose) in combination with intravenous cetuximab once a week (with an initial loading dose of 400 mg per square meter of body-surface area, followed by a dose of 250 mg per square meter) or every 2 weeks (with a dose of 500 mg per square meter). The primary end points were objective response (complete or partial response) and safety. RESULTS: As of June 16, 2022, a total of 44 patients had received adagrasib, and 32 had received combination therapy with adagrasib and cetuximab, with a median follow-up of 20.1 months and 17.5 months, respectively. In the monotherapy group (43 evaluable patients), a response was reported in 19% of the patients (95% confidence interval [CI], 8 to 33). The median response duration was 4.3 months (95% CI, 2.3 to 8.3), and the median progression-free survival was 5.6 months (95% CI, 4.1 to 8.3). In the combination-therapy group (28 evaluable patients), the response was 46% (95% CI, 28 to 66). The median response duration was 7.6 months (95% CI, 5.7 to not estimable), and the median progression-free survival was 6.9 months (95% CI, 5.4 to 8.1). The percentage of grade 3 or 4 treatment-related adverse events was 34% in the monotherapy group and 16% in the combination-therapy group. No grade 5 adverse events were observed. CONCLUSIONS: Adagrasib had antitumor activity in heavily pretreated patients with metastatic colorectal cancer with mutant KRAS G12C, both as oral monotherapy and in combination with cetuximab. The median response duration was more than 6 months in the combination-therapy group. Reversible adverse events were common in the two groups. (Funded by Mirati Therapeutics; KRYSTAL-1 ClinicalTrials.gov number, NCT03785249.).


Assuntos
Antineoplásicos , Cetuximab , Neoplasias Colorretais , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cetuximab/administração & dosagem , Cetuximab/efeitos adversos , Cetuximab/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/secundário , Piperazinas/uso terapêutico , Proteínas Proto-Oncogênicas p21(ras)/genética , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico
4.
Nature ; 588(7836): 124-129, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33268865

RESUMO

Ageing is a degenerative process that leads to tissue dysfunction and death. A proposed cause of ageing is the accumulation of epigenetic noise that disrupts gene expression patterns, leading to decreases in tissue function and regenerative capacity1-3. Changes to DNA methylation patterns over time form the basis of ageing clocks4, but whether older individuals retain the information needed to restore these patterns-and, if so, whether this could improve tissue function-is not known. Over time, the central nervous system (CNS) loses function and regenerative capacity5-7. Using the eye as a model CNS tissue, here we show that ectopic expression of Oct4 (also known as Pou5f1), Sox2 and Klf4 genes (OSK) in mouse retinal ganglion cells restores youthful DNA methylation patterns and transcriptomes, promotes axon regeneration after injury, and reverses vision loss in a mouse model of glaucoma and in aged mice. The beneficial effects of OSK-induced reprogramming in axon regeneration and vision require the DNA demethylases TET1 and TET2. These data indicate that mammalian tissues retain a record of youthful epigenetic information-encoded in part by DNA methylation-that can be accessed to improve tissue function and promote regeneration in vivo.


Assuntos
Envelhecimento/genética , Reprogramação Celular/genética , Metilação de DNA , Epigênese Genética , Olho , Regeneração Nervosa/genética , Visão Ocular/genética , Visão Ocular/fisiologia , Envelhecimento/fisiologia , Animais , Axônios/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular , Proteínas de Ligação a DNA/genética , Dependovirus/genética , Dioxigenases , Modelos Animais de Doenças , Olho/citologia , Olho/inervação , Olho/patologia , Feminino , Vetores Genéticos/genética , Glaucoma/genética , Glaucoma/patologia , Humanos , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Camundongos , Camundongos Endogâmicos C57BL , Fator 3 de Transcrição de Octâmero/genética , Traumatismos do Nervo Óptico/genética , Proteínas Proto-Oncogênicas/genética , Células Ganglionares da Retina/citologia , Fatores de Transcrição SOXB1/genética , Transcriptoma/genética
5.
Nature ; 575(7784): 679-682, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31723262

RESUMO

Caspase-8 is a protease with both pro-death and pro-survival functions: it mediates apoptosis induced by death receptors such as TNFR11, and suppresses necroptosis mediated by the kinase RIPK3 and the pseudokinase MLKL2-4. Mice that lack caspase-8 display MLKL-dependent embryonic lethality4, as do mice that express catalytically inactive CASP8(C362A)5. Casp8C362A/C362AMlkl-/- mice die during the perinatal period5, whereas Casp8-/-Mlkl-/- mice are viable4, which indicates that inactive caspase-8 also has a pro-death scaffolding function. Here we show that mutant CASP8(C362A) induces the formation of ASC (also known as PYCARD) specks, and caspase-1-dependent cleavage of GSDMD and caspases 3 and 7 in MLKL-deficient mouse intestines around embryonic day 18. Caspase-1 and its adaptor ASC contributed to the perinatal lethal phenotype because a number of Casp8C362A/C362AMlkl-/-Casp1-/- and Casp8C362A/C362AMlkl-/-Asc-/- mice survived beyond weaning. Transfection studies suggest that inactive caspase-8 adopts a distinct conformation to active caspase-8, enabling its prodomain to engage ASC. Upregulation of the lipopolysaccharide sensor caspase-11 in the intestines of both Casp8C362A/C362AMlkl-/- and Casp8C362A/C362AMlkl-/-Casp1-/- mice also contributed to lethality because Casp8C362A/C362AMlkl-/-Casp1-/-Casp11-/- (Casp11 is also known as Casp4) neonates survived more often than Casp8C362A/C362AMlkl-/-Casp1-/- neonates. Finally, Casp8C362A/C362ARipk3-/-Casp1-/-Casp11-/- mice survived longer than Casp8C362A/C362AMlkl-/-Casp1-/-Casp11-/- mice, indicating that a necroptosis-independent function of RIPK3 also contributes to lethality. Thus, unanticipated plasticity in death pathways is revealed when caspase-8-dependent apoptosis and MLKL-dependent necroptosis are inhibited.


Assuntos
Caspase 8/metabolismo , Morte Celular/genética , Mucosa Intestinal/citologia , Animais , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Caspase 8/genética , Feminino , Regulação da Expressão Gênica , Células HEK293 , Humanos , Mucosa Intestinal/enzimologia , Estimativa de Kaplan-Meier , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo
6.
J Infect Dis ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38781438

RESUMO

BACKGROUND: Asymptomatic carriage of malaria parasites persists even as malaria transmission declines. Low density infections are often submicroscopic, not detected by rapid diagnostic tests (RDTs) or microscopy, but detectable by PCR. METHODS: To characterize submicroscopic Plasmodium falciparum carriage in an area of declining malaria transmission, asymptomatic persons >5 years of age in rural Bagamoyo District, Tanzania, were screened using RDT, microscopy, and PCR. We investigated the size of the submicroscopic reservoir of infection across villages, determined factors associated with submicroscopic carriage, and assessed the natural history of submicroscopic malaria over four weeks. RESULTS: Among 6,076 participants, P. falciparum prevalence by RDT, microscopy, and PCR was 9%, 9%, and 28%, respectively, with roughly two-thirds of PCR-positive individuals harboring submicroscopic infection. Adult status, female gender, dry season months, screened windows, and bednet use were associated with submicroscopic carriage. Among 15 villages encompassing 80% of participants, the proportion of submicroscopic carriers increased with decreasing village-level malaria prevalence. Over four weeks, 23% (61/266) of submicroscopic carriers became RDT-positive, with half exhibiting symptoms, while half (133/266) were no longer parasitemic at the end of four weeks. Progression to RDT-positive patent malaria occurred more frequently in villages with higher malaria prevalence. CONCLUSIONS: Micro-heterogeneity in transmission observed at the village level appears to impact both the size of the submicroscopic reservoir and the likelihood of submicroscopic carriers developing patent malaria in coastal Tanzania.

7.
Int J Cancer ; 154(1): 28-40, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37615573

RESUMO

Differences in the average age at cancer diagnosis are observed across countries. We therefore aimed to assess international variation in the median age at diagnosis of common cancers worldwide, after adjusting for differences in population age structure. We used IARC's Cancer Incidence in Five Continents (CI5) Volume XI database, comprising cancer diagnoses between 2008 and 2012 from population-based cancer registries in 65 countries. We calculated crude median ages at diagnosis for lung, colon, breast and prostate cancers in each country, then adjusted for population age differences using indirect standardization. We showed that median ages at diagnosis changed by up to 10 years after standardization, typically increasing in low- and middle-income countries (LMICs) and decreasing in high-income countries (HICs), given relatively younger and older populations, respectively. After standardization, the range of ages at diagnosis was 12 years for lung cancer (median age 61-Bulgaria vs 73-Bahrain), 12 years for colon cancer (60-the Islamic Republic of Iran vs 72-Peru), 10 years for female breast cancer (49-Algeria, the Islamic Republic of Iran, Republic of Korea vs 59-USA and others) and 10 years for prostate cancer (65-USA, Lithuania vs 75-Philippines). Compared to HICs, populations in LMICs were diagnosed with colon cancer at younger ages but with prostate cancer at older ages (both pLMICS-vs-HICs < 0.001). In countries with higher smoking prevalence, lung cancers were diagnosed at younger ages in both women and men (both pcorr < 0.001). Female breast cancer tended to be diagnosed at younger ages in East Asia, the Middle East and Africa. Our findings suggest that the differences in median ages at cancer diagnosis worldwide likely reflect population-level variation in risk factors and cancer control measures, including screening.


Assuntos
Neoplasias da Mama , Neoplasias do Colo , Neoplasias Pulmonares , Neoplasias da Próstata , Masculino , Humanos , Pessoa de Meia-Idade , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/epidemiologia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/epidemiologia , Pulmão , Incidência
8.
Int J Cancer ; 154(4): 596-606, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37715370

RESUMO

An estimated 38 million people live with human immunodeficiency virus (HIV) worldwide and are at excess risk for multiple cancer types. Elevated cancer risks in people living with HIV (PLWH) are driven primarily by increased exposure to carcinogens, most notably oncogenic viruses acquired through shared transmission routes, plus acceleration of viral carcinogenesis by HIV-related immunosuppression. In the era of widespread antiretroviral therapy (ART), life expectancy of PLWH has increased, with cancer now a leading cause of co-morbidity and death. Furthermore, the types of cancers occurring among PLWH are shifting over time and vary in their relative burden in different parts of the world. In this context, the International Agency for Research on Cancer (IARC) and the US National Cancer Institute (NCI) convened a meeting in September 2022 of multinational and multidisciplinary experts to focus on cancer in PLWH. This report summarizes the proceedings, including a review of the state of the science of cancer descriptive epidemiology, etiology, molecular tumor characterization, primary and secondary prevention, treatment disparities and survival in PLWH around the world. A consensus of key research priorities and recommendations in these domains is also presented.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Neoplasias , Estados Unidos/epidemiologia , Humanos , HIV , National Cancer Institute (U.S.) , Neoplasias/tratamento farmacológico , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Fármacos Anti-HIV/uso terapêutico
9.
FASEB J ; 37(7): e23042, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37358817

RESUMO

Patients who recover from hospital-acquired pneumonia exhibit a high incidence of end-organ dysfunction following hospital discharge, including cognitive deficits. We have previously demonstrated that pneumonia induces the production and release of cytotoxic oligomeric tau from pulmonary endothelial cells, and these tau oligomers can enter the circulation and may be a cause of long-term morbidities. Endothelial-derived oligomeric tau is hyperphosphorylated during infection. The purpose of these studies was to determine whether Ser-214 phosphorylation of tau is a necessary stimulus for generation of cytotoxic tau variants. The results of these studies demonstrate that Ser-214 phosphorylation is critical for the cytotoxic properties of infection-induced oligomeric tau. In the lung, Ser-214 phosphorylated tau contributes to disruption of the alveolar-capillary barrier, resulting in increased permeability. However, in the brain, both the Ser-214 phosphorylated tau and the mutant Ser-214-Ala tau, which cannot be phosphorylated, disrupted hippocampal long-term potentiation suggesting that inhibition of long-term potentiation was relatively insensitive to the phosphorylation status of Ser-214. Nonetheless, phosphorylation of tau is essential to its cytotoxicity since global dephosphorylation of the infection-induced cytotoxic tau variants rescued long-term potentiation. Collectively, these data demonstrate that multiple forms of oligomeric tau are generated during infectious pneumonia, with different forms of oligomeric tau being responsible for dysfunction of distinct end-organs during pneumonia.


Assuntos
Antineoplásicos , Pneumonia , Humanos , Fosforilação , Proteínas tau/genética , Proteínas tau/metabolismo , Células Endoteliais/metabolismo , Pulmão/metabolismo
10.
J Anim Ecol ; 93(2): 147-158, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38230868

RESUMO

Classifying specimens is a critical component of ecological research, biodiversity monitoring and conservation. However, manual classification can be prohibitively time-consuming and expensive, limiting how much data a project can afford to process. Computer vision, a form of machine learning, can help overcome these problems by rapidly, automatically and accurately classifying images of specimens. Given the diversity of animal species and contexts in which images are captured, there is no universal classifier for all species and use cases. As such, ecologists often need to train their own models. While numerous software programs exist to support this process, ecologists need a fundamental understanding of how computer vision works to select appropriate model workflows based on their specific use case, data types, computing resources and desired performance capabilities. Ecologists may also face characteristic quirks of ecological datasets, such as long-tail distributions, 'unknown' species, similarity between species and polymorphism within species, which impact the efficacy of computer vision. Despite growing interest in computer vision for ecology, there are few resources available to help ecologists face the challenges they are likely to encounter. Here, we present a gentle introduction for species classification using computer vision. In this manuscript and associated GitHub repository, we demonstrate how to prepare training data, basic model training procedures, and methods for model evaluation and selection. Throughout, we explore specific considerations ecologists should make when training classification models, such as data domains, feature extractors and class imbalances. With these basics, ecologists can adjust their workflows to achieve research goals and/or account for uncertainty in downstream analysis. Our goal is to provide guidance for ecologists for getting started in or improving their use of machine learning for visual classification tasks.


Assuntos
Computadores , Redes Neurais de Computação , Animais , Aprendizado de Máquina , Biodiversidade
11.
Pediatr Blood Cancer ; 71(7): e31051, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38706187

RESUMO

It is not clear whether trial access disparities exist in the Children's Oncology Group (COG). Here, we leverage a cohort of children with high-risk neuroblastoma (HR-NBL) enrolled on the COG ANBL00B1 neuroblastoma biology study to examine subsequent enrollment to upfront COG therapeutic trials by race, ethnicity, and proxied poverty status. Among 1917 children with HR-NBL enrolled on ANBL00B1, 696 (36.3%) subsequently enrolled on an upfront therapeutic trial with no difference by race, ethnicity, or proxied poverty status. In neuroblastoma, trial access disparities are not comparable to adult oncology, and efforts to advance equity should prioritize other mechanisms of survival disparities.


Assuntos
Neuroblastoma , Pobreza , Humanos , Neuroblastoma/terapia , Neuroblastoma/etnologia , Masculino , Feminino , Criança , Pré-Escolar , Lactente , Etnicidade/estatística & dados numéricos , Ensaios Clínicos como Assunto/estatística & dados numéricos , Disparidades em Assistência à Saúde , Adolescente , Seguimentos
12.
Arch Sex Behav ; 53(4): 1541-1559, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38472604

RESUMO

Pre-exposure prophylaxis (PrEP) use may be associated with condom use decisions. The current investigation examined sexual decision-making in the context of PrEP among young adult men who have sex with men (MSM) between 18 and 30 years old, using an explanatory sequential mixed methods design. For the quantitative aim, 99 MSM currently taking PrEP (i.e., PrEP-experienced) and 140 MSM not currently taking PrEP (i.e., PrEP-naive) completed an online survey, including the Sexual Delay Discounting Task (SDDT), which captures likelihood of condom use. For the qualitative aim, 15 people from each group were interviewed about their (1) conceptualizations of risky sex and (2) ways they manage their sexual risk. Participants were, on average, 25.69 years old (SD = 3.07) and 64% White. Results from the quantitative aim revealed, controlling for covariates, PrEP-experienced participants exhibited significantly lower likelihood of (1) using an immediately available condom and (2) waiting for a delayed condom (i.e., sexual delay discounting) compared to PrEP-naive participants. Qualitative themes explaining what young adult MSM consider to be risky sex included: (1) any sex as risky sex, (2) risky sex as "sex without a conversation," and (3) risky sex as sex with risk for physical harm. Themes on ways young adult MSM manage sexual risk were classified as proactive, reactive, and passive. Results suggest that PrEP use is related to condom use decisions. Taken together, quantitative differences in sexual delay discounting, but qualitatively similar conceptualizations and management of risky sex, suggest that the SDDT may be a useful tool in sex research to capture processes (i.e., delay discounting) underlying sexual decision-making that may be missed by traditional self-reports. Implications of results, including potentially providing (good quality) condoms with every PrEP prescription, and future research topics are discussed.


Assuntos
Infecções por HIV , Profilaxia Pré-Exposição , Minorias Sexuais e de Gênero , Masculino , Adulto Jovem , Humanos , Adolescente , Adulto , Homossexualidade Masculina , Profilaxia Pré-Exposição/métodos , Economia Comportamental , Infecções por HIV/prevenção & controle , Comportamento Sexual , Preservativos
13.
Am J Respir Cell Mol Biol ; 69(3): 340-354, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37201952

RESUMO

Pulmonary microvascular endothelial cells contribute to the integrity of the lung gas exchange interface, and they are highly glycolytic. Although glucose and fructose represent discrete substrates available for glycolysis, pulmonary microvascular endothelial cells prefer glucose over fructose, and the mechanisms involved in this selection are unknown. 6-Phosphofructo-2-kinase/fructose-2, 6-bisphosphatase 3 (PFKFB3) is an important glycolytic enzyme that drives glycolytic flux against negative feedback and links glycolytic and fructolytic pathways. We hypothesized that PFKFB3 inhibits fructose metabolism in pulmonary microvascular endothelial cells. We found that PFKFB3 knockout cells survive better than wild-type cells in fructose-rich medium under hypoxia. Seahorse assays, lactate and glucose measurements, and stable isotope tracing showed that PFKFB3 inhibits fructose-hexokinase-mediated glycolysis and oxidative phosphorylation. Microarray analysis revealed that fructose upregulates PFKFB3, and PFKFB3 knockout cells increase fructose-specific GLUT5 (glucose transporter 5) expression. Using conditional endothelial-specific PFKFB3 knockout mice, we demonstrated that endothelial PFKFB3 knockout increases lung tissue lactate production after fructose gavage. Last, we showed that pneumonia increases fructose in BAL fluid in mechanically ventilated ICU patients. Thus, PFKFB3 knockout increases GLUT5 expression and the hexokinase-mediated fructose use in pulmonary microvascular endothelial cells that promotes their survival. Our findings indicate that PFKFB3 is a molecular switch that controls glucose versus fructose use in glycolysis and help better understand lung endothelial cell metabolism during respiratory failure.


Assuntos
Células Endoteliais , Frutose , Hexoquinase , Animais , Camundongos , Células Endoteliais/metabolismo , Glucose/metabolismo , Lactatos , Pulmão/metabolismo , Frutose/metabolismo
14.
Am J Physiol Lung Cell Mol Physiol ; 325(2): L174-L189, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37366533

RESUMO

Pneumonia elicits the production of cytotoxic beta amyloid (Aß) that contributes to end-organ dysfunction, yet the mechanism(s) linking infection to activation of the amyloidogenic pathway that produces cytotoxic Aß is unknown. Here, we tested the hypothesis that gamma-secretase activating protein (GSAP), which contributes to the amyloidogenic pathway in the brain, promotes end-organ dysfunction following bacterial pneumonia. First-in-kind Gsap knockout rats were generated. Wild-type and knockout rats possessed similar body weights, organ weights, circulating blood cell counts, arterial blood gases, and cardiac indices at baseline. Intratracheal Pseudomonas aeruginosa infection caused acute lung injury and a hyperdynamic circulatory state. Whereas infection led to arterial hypoxemia in wild-type rats, the alveolar-capillary barrier integrity was preserved in Gsap knockout rats. Infection potentiated myocardial infarction following ischemia-reperfusion injury, and this potentiation was abolished in knockout rats. In the hippocampus, GSAP contributed to both pre- and postsynaptic neurotransmission, increasing the presynaptic action potential recruitment, decreasing neurotransmitter release probability, decreasing the postsynaptic response, and preventing postsynaptic hyperexcitability, resulting in greater early long-term potentiation but reduced late long-term potentiation. Infection abolished early and late long-term potentiation in wild-type rats, whereas the late long-term potentiation was partially preserved in Gsap knockout rats. Furthermore, hippocampi from knockout rats, and both the wild-type and knockout rats following infection, exhibited a GSAP-dependent increase in neurotransmitter release probability and postsynaptic hyperexcitability. These results elucidate an unappreciated role for GSAP in innate immunity and highlight the contribution of GSAP to end-organ dysfunction during infection.NEW & NOTEWORTHY Pneumonia is a common cause of end-organ dysfunction, both during and in the aftermath of infection. In particular, pneumonia is a common cause of lung injury, increased risk of myocardial infarction, and neurocognitive dysfunction, although the mechanisms responsible for such increased risk are unknown. Here, we reveal that gamma-secretase activating protein, which contributes to the amyloidogenic pathway, is important for end-organ dysfunction following infection.


Assuntos
Doença de Alzheimer , Pneumonia Bacteriana , Ratos , Animais , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Insuficiência de Múltiplos Órgãos , Peptídeos beta-Amiloides/metabolismo , Neurotransmissores
15.
Int J Cancer ; 153(6): 1182-1191, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37278097

RESUMO

Burkitt lymphoma (BL) is an aggressive B-cell lymphoma that occurs worldwide. A study of BL in the US National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) program during 1973 to 2005 (n = 3043) revealed three age-specific incidence peaks of BL and rates that were rising. We studied BL cases diagnosed in SEER 22 during 2000 to 2019 (n = 11 626) to investigate age-specific BL incidence rates and temporal trends. The age-standardized BL incidence rate was 3.96/million person-years, with a 2.85:1 male-to-female ratio. The BL rate among both Hispanic and White individuals was higher than in Black individuals (4.52, 4.12 vs 3.14). Age-specific BL rates showed peaks during pediatric, adult and elderly years in males and pediatric and elderly peaks in females. Based on 4524 BL cases with HIV status (SEER 13), only one peak in adult males (45 years) was observed. Overall age-standardized BL incidence rates rose 1.2%/year (not significant) up to 2009 then fell significantly by 2.4%/year thereafter. Temporal trends in BL rates during 2000 to 2019 varied with age group as pediatric BL rates rose 1.1%/year, while elderly BL rates fell 1.7%/year and adult BL rates rose 3.4%/year until 2007 before falling 3.1%/year thereafter. Overall survival from BL was 64% at 2 years, being highest in pediatric patients and lowest in Black and elderly individuals vs other subgroups. Survival improved by 20% between 2000 and 2019. Our data suggest that BL age-specific incidence rates are multimodal and that overall BL rates rose up to 2009 and then fell, suggesting changes in etiological factors or diagnosis.


Assuntos
Linfoma de Burkitt , Neoplasias , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , População Negra/estatística & dados numéricos , Linfoma de Burkitt/epidemiologia , Incidência , Estados Unidos/epidemiologia , Brancos/estatística & dados numéricos , Hispânico ou Latino/estatística & dados numéricos , Pessoa de Meia-Idade
16.
Int J Cancer ; 153(1): 64-72, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36929885

RESUMO

In the United States, renal cell carcinoma (RCC) incidence and the prevalence of obesity, an established risk factor for RCC, have been increasing for several decades. RCC is more common among older individuals. We sought to quantify the contribution of excess adiposity to the rising incidence of RCC among individuals 60 years or older. National Institutes of Health-American Association of Retired Persons Diet and Health Study data (n = 453 859 participants, enrolled in 1995-1996, age at enrollment 50-71 years) were used to estimate multivariable-adjusted hazard ratios (HRs) for RCC across body mass index categories and HRs associated with smoking. Population attributable fractions (PAFs) were calculated using estimated HRs and annual overweight/obesity prevalence from the National Health Interview Survey (1985-2008). PAF estimates were combined with RCC incidence from Surveillance, Epidemiology and End Results-13 to calculate annual percent changes in RCC incidence attributable (and unrelated) to overweight/obesity. We found that between 1995 and 2018, among individuals aged 60 years and older, PAF for overweight/obesity increased from 18% to 29% for all RCCs. In comparison, the PAF for smoking declined from 12% to 9%. RCC incidence increased 1.8% per year (95% confidence interval [CI] 1.5%-2.1%) overall, while RCC incidence attributable to overweight/obesity increased 3.8% per year (95%CI 3.5%-4.2%) and RCC incidence unrelated to overweight/obesity increased 1.2% per year (95% CI 0.9%-1.4%). In conclusion, overweight/obesity appears to have contributed importantly to the rising incidence of RCC in the United States since the mid-1990s. Public health interventions focused on reducing overweight and obesity could help substantially in curbing this trend.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Estados Unidos/epidemiologia , Pessoa de Meia-Idade , Idoso , Carcinoma de Células Renais/epidemiologia , Sobrepeso/complicações , Sobrepeso/epidemiologia , Incidência , Obesidade/complicações , Obesidade/epidemiologia , Fatores de Risco , Neoplasias Renais/epidemiologia , Neoplasias Renais/etiologia , Índice de Massa Corporal
17.
Int J Cancer ; 152(10): 2052-2060, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36650690

RESUMO

In Costa Rica (CR), only one report on head and neck cancer (HNC) incidence trends (1985-2007) has been published and no investigations on the epidemiology of potentially human papillomavirus (HPV)-related and HPV-unrelated HNCs have been done. We examined the age-standardized incidence rates (IRs) and trends of head and neck squamous cell carcinomas (HNSCC) and compared incidence trends of potentially HPV-related and HPV-unrelated HNSCCs. We obtained all available HNC cases for the period 2006-2015 from the Costa Rican National Cancer Registry of Tumors and the population estimates from the Costa Rican National Institute of Statistics and Census. The analysis was restricted to invasive HNSCCs (n = 1577). IRs and incidence rate ratios were calculated using SEER*Stat software and were age-standardized for the 2010 Costa Rican population. Joinpoint regression analysis program was used to calculate trends and annual percent changes (APCs) in rates. For all HNSCCs, the age-standardized IR was 34.0/million person-years; 95% CI 32.4, 35.8. There was a significant decline in the incidence of nasopharyngeal cancer (APC: -5.9% per year; 95% CI -10.8, -0.7) and laryngeal cancer (APC: -5.4% per year; -9.2, 1.5). The incidence trends for hypopharyngeal, oropharyngeal and oral cavity cancers each remained stable over time. HNSCCs were categorized by their potential relatedness to HPV infection. Though the APCs were not statistically significant, IRs of potentially HPV-related HNSCCs trended upward, while HPV-unrelated HNSCCs trended downward. HNSCCs are uncommon in CR and decreased over time. We observed a divergent pattern of decreasing HPV-unrelated with increasing HPV-related HNSCCs that should be further informed by HPV genotyping tumor samples.


Assuntos
Neoplasias de Cabeça e Pescoço , Neoplasias Nasofaríngeas , Infecções por Papillomavirus , Humanos , Adulto , Carcinoma de Células Escamosas de Cabeça e Pescoço , Incidência , Papillomavirus Humano , Costa Rica
18.
Cancer Metastasis Rev ; 41(3): 607-625, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35752704

RESUMO

Obesity, exceptionally prevalent in the USA, promotes the incidence and progression of numerous cancer types including breast cancer. Complex, interacting metabolic and immune dysregulation marks the development of both breast cancer and obesity. Obesity promotes chronic low-grade inflammation, particularly in white adipose tissue, which drives immune dysfunction marked by increased pro-inflammatory cytokine production, alternative macrophage activation, and reduced T cell function. Breast tissue is predominantly composed of white adipose, and developing breast cancer readily and directly interacts with cells and signals from adipose remodeled by obesity. This review discusses the biological mechanisms through which obesity promotes breast cancer, the role of obesity in breast cancer health disparities, and dietary interventions to mitigate the adverse effects of obesity on breast cancer. We detail the intersection of obesity and breast cancer, with an emphasis on the shared and unique patterns of immune dysregulation in these disease processes. We have highlighted key areas of breast cancer biology exacerbated by obesity, including incidence, progression, and therapeutic response. We posit that interception of obesity-driven breast cancer will require interventions that limit protumor signaling from obese adipose tissue and that consider genetic, structural, and social determinants of the obesity-breast cancer link. Finally, we detail the evidence for various dietary interventions to offset obesity effects in clinical and preclinical studies of breast cancer. In light of the strong associations between obesity and breast cancer and the rising rates of obesity in many parts of the world, the development of effective, safe, well-tolerated, and equitable interventions to limit the burden of obesity on breast cancer are urgently needed.


Assuntos
Neoplasias da Mama , Tecido Adiposo/metabolismo , Neoplasias da Mama/complicações , Neoplasias da Mama/etiologia , Feminino , Humanos , Inflamação/metabolismo , Obesidade/complicações , Obesidade/metabolismo
19.
PLoS Pathog ; 17(2): e1009291, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33529209

RESUMO

Acinetobacter baumannii is a highly antibiotic-resistant bacterial pathogen for which novel therapeutic approaches are needed. Unfortunately, the drivers of virulence in A. baumannii remain uncertain. By comparing genomes among a panel of A. baumannii strains we identified a specific gene variation in the capsule locus that correlated with altered virulence. While less virulent strains possessed the intact gene gtr6, a hypervirulent clinical isolate contained a spontaneous transposon insertion in the same gene, resulting in the loss of a branchpoint in capsular carbohydrate structure. By constructing isogenic gtr6 mutants, we confirmed that gtr6-disrupted strains were protected from phagocytosis in vitro and displayed higher bacterial burden and lethality in vivo. Gtr6+ strains were phagocytized more readily and caused lower bacterial burden and no clinical illness in vivo. We found that the CR3 receptor mediated phagocytosis of gtr6+, but not gtr6-, strains in a complement-dependent manner. Furthermore, hypovirulent gtr6+ strains demonstrated increased virulence in vivo when CR3 function was abrogated. In summary, loss-of-function in a single capsule assembly gene dramatically altered virulence by inhibiting complement deposition and recognition by phagocytes across multiple A. baumannii strains. Thus, capsular structure can determine virulence among A. baumannii strains by altering bacterial interactions with host complement-mediated opsonophagocytosis.


Assuntos
Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/patogenicidade , Cápsulas Bacterianas/fisiologia , Fagócitos/virologia , Fagocitose , Polissacarídeos Bacterianos/química , Virulência , Infecções por Acinetobacter/genética , Infecções por Acinetobacter/metabolismo , Animais , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Fagócitos/metabolismo , Células RAW 264.7
20.
Psychol Med ; 53(6): 2205-2215, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-34620265

RESUMO

BACKGROUND: The role of interpersonal relationship functioning in trauma recovery is well-established. However, much of this research has been done with cross-sectional samples, often years after trauma exposure, using self-report methodology only, and is focused on intimate relationship adjustment. METHODS: The current study investigated the longitudinal associations between interpersonal (intimate and non-intimate) relationship functioning and clinician- and self-reported posttraumatic stress disorder (PTSD) symptoms in 151 recently (within the past 6 months) traumatized individuals. Participants were assessed at four time points over 1 year. RESULTS: Approximately 53% of the sample was diagnosed with PTSD at initial assessment, with declining rates of diagnostic status over time to 16%. Latent difference score (LDS) modeling revealed nonlinear declines in both clinician-assessed and self-reported PTSD symptom severity, with faster declines in earlier periods. Likewise, LDS models revealed nonlinear declines in negative (conflict) aspects of interpersonal relationship functioning, but linear declines in positive (support, depth) aspects. The relationship between PTSD and relationship functioning differed for clinician- and self-reported PTSD. Bivariate LDS modeling revealed significant cross-lagged effects from relationship conflict to clinician-assessed PTSD, and significant cross-lagged effects from self-reported PTSD to relationship conflict over time. CONCLUSIONS: These results highlight that the variability in prior results may be related to the method of assessing PTSD symptomatology and different relational constructs. Implications for theory and early intervention are discussed.


Assuntos
Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Estudos Transversais , Relações Interpessoais , Parceiros Sexuais , Comportamento Sexual
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