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1.
Cell ; 185(14): 2591-2608.e30, 2022 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-35803246

RESUMEN

Melanoma brain metastasis (MBM) frequently occurs in patients with advanced melanoma; yet, our understanding of the underlying salient biology is rudimentary. Here, we performed single-cell/nucleus RNA-seq in 22 treatment-naive MBMs and 10 extracranial melanoma metastases (ECMs) and matched spatial single-cell transcriptomics and T cell receptor (TCR)-seq. Cancer cells from MBM were more chromosomally unstable, adopted a neuronal-like cell state, and enriched for spatially variably expressed metabolic pathways. Key observations were validated in independent patient cohorts, patient-derived MBM/ECM xenograft models, RNA/ATAC-seq, proteomics, and multiplexed imaging. Integrated spatial analyses revealed distinct geography of putative cancer immune evasion and evidence for more abundant intra-tumoral B to plasma cell differentiation in lymphoid aggregates in MBM. MBM harbored larger fractions of monocyte-derived macrophages and dysfunctional TOX+CD8+ T cells with distinct expression of immune checkpoints. This work provides comprehensive insights into MBM biology and serves as a foundational resource for further discovery and therapeutic exploration.


Asunto(s)
Neoplasias Encefálicas , Melanoma , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/secundario , Linfocitos T CD8-positivos/patología , Ecosistema , Humanos , RNA-Seq
2.
Nat Immunol ; 24(10): 1645-1653, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37709986

RESUMEN

Persistent exposure to antigen during chronic infection or cancer renders T cells dysfunctional. The molecular mechanisms regulating this state of exhaustion are thought to be common in infection and cancer, despite obvious differences in their microenvironments. Here we found that NFAT5, an NFAT family transcription factor that lacks an AP-1 docking site, was highly expressed in exhausted CD8+ T cells in the context of chronic infections and tumors but was selectively required in tumor-induced CD8+ T cell exhaustion. Overexpression of NFAT5 in CD8+ T cells reduced tumor control, while deletion of NFAT5 improved tumor control by promoting the accumulation of tumor-specific CD8+ T cells that had reduced expression of the exhaustion-associated proteins TOX and PD-1 and produced more cytokines, such as IFNÉ£ and TNF, than cells with wild-type levels of NFAT5, specifically in the precursor exhausted PD-1+TCF1+TIM-3-CD8+ T cell population. NFAT5 did not promote T cell exhaustion during chronic infection with clone 13 of lymphocytic choriomeningitis virus. Expression of NFAT5 was induced by TCR triggering, but its transcriptional activity was specific to the tumor microenvironment and required hyperosmolarity. Thus, NFAT5 promoted the exhaustion of CD8+ T cells in a tumor-selective fashion.


Asunto(s)
Coriomeningitis Linfocítica , Neoplasias , Humanos , Factores de Transcripción/metabolismo , Linfocitos T CD8-positivos , Agotamiento de Células T , Infección Persistente , Microambiente Tumoral , Receptor de Muerte Celular Programada 1/genética , Receptor de Muerte Celular Programada 1/metabolismo , Virus de la Coriomeningitis Linfocítica , Neoplasias/metabolismo
3.
Nat Immunol ; 24(5): 869-883, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37081150

RESUMEN

To date, no immunotherapy approaches have managed to fully overcome T-cell exhaustion, which remains a mandatory fate for chronically activated effector cells and a major therapeutic challenge. Understanding how to reprogram CD8+ tumor-infiltrating lymphocytes away from exhausted effector states remains an elusive goal. Our work provides evidence that orthogonal gene engineering of T cells to secrete an interleukin (IL)-2 variant binding the IL-2Rßγ receptor and the alarmin IL-33 reprogrammed adoptively transferred T cells to acquire a novel, synthetic effector state, which deviated from canonical exhaustion and displayed superior effector functions. These cells successfully overcame homeostatic barriers in the host and led-in the absence of lymphodepletion or exogenous cytokine support-to high levels of engraftment and tumor regression. Our work unlocks a new opportunity of rationally engineering synthetic CD8+ T-cell states endowed with the ability to avoid exhaustion and control advanced solid tumors.


Asunto(s)
Linfocitos T CD8-positivos , Inmunoterapia Adoptiva , Interleucina-2 , Neoplasias Experimentales , Linfocitos T CD8-positivos/inmunología , Agotamiento de Células T , Linfocitos Infiltrantes de Tumor/inmunología , Interleucina-2/farmacología , Interleucina-33 , Ingeniería de Proteínas , Femenino , Animales , Ratones , Ratones Endogámicos C57BL , Línea Celular Tumoral , Neoplasias Experimentales/terapia , Receptor de Muerte Celular Programada 1/metabolismo
4.
Nature ; 613(7943): 298-302, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36631652

RESUMEN

Bed load sediment transport, in which wind or water flowing over a bed of sediment causes grains to roll or hop along the bed, is a critically important mechanism in contexts ranging from river restoration1 to planetary exploration2. Despite its widespread occurrence, predictions of bed load sediment flux are notoriously imprecise3,4. Many studies have focused on grain size variability5 as a source of uncertainty, but few have investigated the role of grain shape, even though shape has long been suspected to influence transport rates6. Here we show that grain shape can modify bed load transport rates by an amount comparable to the scatter in many sediment transport datasets4,7,8. We develop a theory that accounts for grain shape effects on fluid drag and granular friction and predicts that the onset and efficiency of transport depend on the coefficients of drag and bulk friction of the transported grains. Laboratory experiments confirm these predictions and reveal that the effect of grain shape on sediment transport can be difficult to intuit from the appearance of grains. We propose a shape-corrected sediment transport law that collapses our experimental measurements. Our results enable greater accuracy in predictions of sediment transport and help reconcile theories developed for spherical particles with the behaviour of natural sediment grains.

5.
Immunity ; 50(1): 195-211.e10, 2019 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-30635237

RESUMEN

Checkpoint blockade mediates a proliferative response of tumor-infiltrating CD8+ T lymphocytes (TILs). The origin of this response has remained elusive because chronic activation promotes terminal differentiation or exhaustion of tumor-specific T cells. Here we identified a subset of tumor-reactive TILs bearing hallmarks of exhausted cells and central memory cells, including expression of the checkpoint protein PD-1 and the transcription factor Tcf1. Tcf1+PD-1+ TILs mediated the proliferative response to immunotherapy, generating both Tcf1+PD-1+ and differentiated Tcf1-PD-1+ cells. Ablation of Tcf1+PD-1+ TILs restricted responses to immunotherapy. Tcf1 was not required for the generation of Tcf1+PD-1+ TILs but was essential for the stem-like functions of these cells. Human TCF1+PD-1+ cells were detected among tumor-reactive CD8+ T cells in the blood of melanoma patients and among TILs of primary melanomas. Thus, immune checkpoint blockade relies not on reversal of T cell exhaustion programs, but on the proliferation of a stem-like TIL subset.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Linfocitos T CD8-positivos/inmunología , Factor Nuclear 1-alfa del Hepatocito/metabolismo , Linfocitos Infiltrantes de Tumor/inmunología , Melanoma/terapia , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Células Madre/inmunología , Subgrupos de Linfocitos T/inmunología , Animales , Linfocitos T CD8-positivos/efectos de los fármacos , Diferenciación Celular , Proliferación Celular , Receptor 2 Celular del Virus de la Hepatitis A/antagonistas & inhibidores , Factor Nuclear 1-alfa del Hepatocito/genética , Humanos , Inmunoterapia , Linfocitos Infiltrantes de Tumor/efectos de los fármacos , Melanoma/inmunología , Melanoma Experimental , Ratones , Ratones Endogámicos C57BL
6.
Am J Hum Genet ; 109(12): 2110-2125, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36400022

RESUMEN

The use of population descriptors such as race, ethnicity, and ancestry in science, medicine, and public health has a long, complicated, and at times dark history, particularly for genetics, given the field's perceived importance for understanding between-group differences. The historical and potential harms that come with irresponsible use of these categories suggests a clear need for definitive guidance about when and how they can be used appropriately. However, while many prior authors have provided such guidance, no established consensus exists, and the extant literature has not been examined for implied consensus and sources of disagreement. Here, we present the results of a scoping review of published normative recommendations regarding the use of population categories, particularly in genetics research. Following PRISMA guidelines, we extracted recommendations from n = 121 articles matching inclusion criteria. Articles were published consistently throughout the time period examined and in a broad range of journals, demonstrating an ongoing and interdisciplinary perceived need for guidance. Examined recommendations fall under one of eight themes identified during analysis. Seven are characterized by broad agreement across articles; one, "appropriate definitions of population categories and contexts for use," revealed substantial fundamental disagreement among articles. Additionally, while many articles focus on the inappropriate use of race, none fundamentally problematize ancestry. This work can be a resource to researchers looking for normative guidance on the use of population descriptors and can orient authors of future guidelines to this complex field, thereby contributing to the development of more effective future guidelines for genetics research.


Asunto(s)
Etnicidad , Problema de Conducta , Humanos , Pueblo Asiatico , Consenso , Etnicidad/genética , Investigadores
7.
Cell Mol Life Sci ; 81(1): 348, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136766

RESUMEN

The biological clock in eukaryotes controls daily rhythms in physiology and behavior. It displays a complex organization that involves the molecular transcriptional clock and the redox oscillator which may coordinately work to control cellular rhythms. The redox oscillator has emerged very early in evolution in adaptation to the environmental changes in O2 levels and has been shown to regulate daily rhythms in glycerolipid (GL) metabolism in different eukaryotic cells. GLs are key components of lipid droplets (LDs), intracellular storage organelles, present in all living organisms, and essential for energy and lipid homeostasis regulation and survival; however, the cell bioenergetics status is not constant across time and depends on energy demands. Thus, the formation and degradation of LDs may reflect a time-dependent process following energy requirements. This work investigated the presence of metabolic rhythms in LD content along evolution by studying prokaryotic and eukaryotic cells and organisms. We found sustained temporal oscillations in LD content in Pseudomonas aeruginosa bacteria and Caenorhabditis elegans synchronized by temperature cycles, in serum-shock synchronized human embryonic kidney cells (HEK 293 cells) and brain tumor cells (T98G and GL26) after a dexamethasone pulse. Moreover, in synchronized T98G cells, LD oscillations were altered by glycogen synthase kinase-3 (GSK-3) inhibition that affects the cytosolic activity of the metabolic oscillator or by knocking down LIPIN-1, a key GL synthesizing enzyme. Overall, our findings reveal the existence of metabolic oscillations in terms of LD content highly conserved across evolutionary scales notwithstanding variations in complexity, regulation, and cell organization.


Asunto(s)
Caenorhabditis elegans , Gotas Lipídicas , Pseudomonas aeruginosa , Humanos , Gotas Lipídicas/metabolismo , Animales , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Células HEK293 , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/genética , Relojes Biológicos/genética , Evolución Biológica , Metabolismo de los Lípidos/genética , Ritmo Circadiano/genética , Ritmo Circadiano/fisiología
8.
J Pharmacol Exp Ther ; 389(3): 258-267, 2024 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-38135508

RESUMEN

The cognitive impairments that are often observed in patients with alcohol use disorder (AUD) partially contribute to the extremely low rates of treatment initiation and adherence. Brain acetylcholine receptors (AChR) mediate and modulate cognitive and reward-related behavior, and their distribution can be altered by long-term heavy drinking. Therefore, AChRs are promising pharmacotherapeutic targets for treating the cognitive symptoms of AUD. In the present study, the procognitive efficacy of two AChR agonists, xanomeline and varenicline, were evaluated in group-housed monkeys who self-administered ethanol for more than 1 year. The muscarinic AChR antagonist scopolamine was used to disrupt performance of a serial stimulus discrimination and reversal (SDR) task designed to probe cognitive flexibility, defined as the ability to modify a previously learned behavior in response to a change in reinforcement contingencies. The ability of xanomeline and varenicline to remediate the disruptive effects of scopolamine was compared between socially dominant and subordinate monkeys, with lighter and heavier drinking histories, respectively. We hypothesized that subordinate monkeys would be more sensitive to all three drugs. Scopolamine dose-dependently impaired performance on the serial SDR task in all monkeys at doses lower than those that produced nonspecific impairments (e.g., sedation); its potency did not differ between dominant and subordinate monkeys. However, both AChR agonists were effective in remediating the scopolamine-induced deficit in subordinate monkeys but not in dominant monkeys. These findings suggest xanomeline and varenicline may be effective for enhancing cognitive flexibility in individuals with a history of heavy drinking. SIGNIFICANCE STATEMENT: Procognitive effects of two acetylcholine (ACh) receptor agonists were assessed in group-housed monkeys who had several years' experience drinking ethanol. The muscarinic ACh receptor agonist xanomeline and the nicotinic ACh receptor agonist varenicline reversed a cognitive deficit induced by the muscarinic ACh receptor antagonist scopolamine. However, this effect was observed only in lower-ranking (subordinate) monkeys and not higher-ranking (dominant monkeys). Results suggest that ACh agonists may effectively remediate alcohol-induced cognitive deficits in a subpopulation of those with alcohol use disorder.


Asunto(s)
Etanol , Macaca fascicularis , Escopolamina , Animales , Masculino , Etanol/farmacología , Escopolamina/farmacología , Cognición/efectos de los fármacos , Consumo de Bebidas Alcohólicas/tratamiento farmacológico , Consumo de Bebidas Alcohólicas/psicología , Vareniclina/farmacología , Agonistas Colinérgicos/farmacología , Nootrópicos/farmacología
9.
Cell Mol Neurobiol ; 44(1): 51, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38907776

RESUMEN

The circadian system is a conserved time-keeping machinery that regulates a wide range of processes such as sleep/wake, feeding/fasting, and activity/rest cycles to coordinate behavior and physiology. Circadian disruption can be a contributing factor in the development of metabolic diseases, inflammatory disorders, and higher risk of cancer. Glioblastoma (GBM) is a highly aggressive grade 4 brain tumor that is resistant to conventional therapies and has a poor prognosis after diagnosis, with a median survival of only 12-15 months. GBM cells kept in culture were shown to contain a functional circadian oscillator. In seeking more efficient therapies with lower side effects, we evaluated the pharmacological modulation of the circadian clock by targeting the cytosolic kinases glycogen synthase kinase-3 (GSK-3) and casein kinase 1 ε/δ (CK1ε/δ) with specific inhibitors (CHIR99021 and PF670462, respectively), the cryptochrome protein stabilizer (KL001), or circadian disruption after Per2 knockdown expression in GBM-derived cells. CHIR99021-treated cells had a significant effect on cell viability, clock protein expression, migration, and cell cycle distribution. Moreover, cultures exhibited higher levels of reactive oxygen species and alterations in lipid droplet content after GSK-3 inhibition compared to control cells. The combined treatment of CHIR99021 with temozolomide was found to improve the effect on cell viability compared to temozolomide therapy alone. Per2 disruption affected both GBM migration and cell cycle progression. Overall, our results suggest that pharmacological modulation or molecular clock disruption severely affects GBM cell biology.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Glioblastoma/patología , Glioblastoma/metabolismo , Glioblastoma/tratamiento farmacológico , Humanos , Línea Celular Tumoral , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/tratamiento farmacológico , Piridinas/farmacología , Supervivencia Celular/efectos de los fármacos , Citosol/metabolismo , Citosol/efectos de los fármacos , Glucógeno Sintasa Quinasa 3/metabolismo , Pirimidinas/farmacología , Movimiento Celular/efectos de los fármacos , Relojes Circadianos/efectos de los fármacos , Relojes Circadianos/fisiología , Proteínas CLOCK/metabolismo , Proteínas CLOCK/genética , Proteínas Circadianas Period/metabolismo , Proteínas Circadianas Period/genética , Especies Reactivas de Oxígeno/metabolismo
10.
FASEB J ; 37(7): e23001, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37249913

RESUMEN

Cardiac arrest (CA) and concomitant post-CA syndrome lead to a lethal condition characterized by systemic ischemia-reperfusion injury. Oxygen (O2 ) supply during cardiopulmonary resuscitation (CPR) is the key to success in resuscitation, but sustained hyperoxia can produce toxic effects post CA. However, only few studies have investigated the optimal duration and dosage of O2 administration. Herein, we aimed to determine whether high concentrations of O2 at resuscitation are beneficial or harmful. After rats were resuscitated from the 10-min asphyxia, mechanical ventilation was restarted at an FIO2 of 1.0 or 0.3. From 10 min after initiating CPR, FIO2 of both groups were maintained at 0.3. Bio-physiological parameters including O2 consumption (VO2 ) and mRNA gene expression in multiple organs were evaluated. The FIO2 0.3 group decreased VO2 , delayed the time required to achieve peak MAP, lowered ejection fraction (75.1 ± 3.3% and 59.0 ± 5.7% with FIO2 1.0 and 0.3, respectively; p < .05), and increased blood lactate levels (4.9 ± 0.2 mmol/L and 5.6 ± 0.2 mmol/L, respectively; p < .05) at 10 min after CPR. FIO2 0.3 group had significant increases in hypoxia-inducible factor, inflammatory, and apoptosis-related mRNA gene expression in the brain. Likewise, significant upregulations of hypoxia-inducible factor and apoptosis-related gene expression were observed in the FIO2 0.3 group in the heart and lungs. Insufficient O2 supplementation in the first 10 min of resuscitation could prolong ischemia, and may result in unfavorable biological responses 2 h after CA. Faster recovery from the impairment of O2 metabolism might contribute to the improvement of hemodynamics during the early post-resuscitation phase; therefore, it may be reasonable to provide the maximum feasible O2 concentrations during CPR.


Asunto(s)
Reanimación Cardiopulmonar , Paro Cardíaco , Ratas , Animales , Oxígeno , Paro Cardíaco/terapia , Hemodinámica , Hipoxia , Modelos Animales de Enfermedad
11.
Langmuir ; 40(25): 12888-12898, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38872416

RESUMEN

In this work, we study the relationship between the molecular water layer (MWL) and frost freezing onset and propagation. The progression of frost has been reported to be governed by various localized icing phenomena, including interdroplet ice bridging, dry zones, and frost halos. Reports studying the state of water on surfaces have revealed the presence of a thin nanometer water layer on a range of surfaces. Regardless of further investigations that show environmental humidity, temperature, and surface energy to affect the thickness of the MWL on surfaces, the influence of the MWL on frost nucleation and propagation has not yet been previously addressed in the literature. To study the effect of the MWL on surface freezing events, a range of surface-functionalized glass substrates were prepared. In situ monitoring of freezing events with thermal imaging allowed studying the effect of surface chemistry and environmental relative humidity (RH) on the thickness and continuity of the MWL. We argue that the observed icing nucleation and propagation kinetics are directly related to the presence and continuity of the MWL, which can be manipulated by controlling the environmental humidity and surface chemistry.

12.
Ann Bot ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39223914

RESUMEN

BACKGROUND AND AIMS: Flower-visitor interactions comprise a continuum of behaviors, from mutualistic partners to antagonistic visitors. Despite being relatively frequent in natural communities, florivory remains unexplored, especially when comprising abiotic factors, spatio-temporal variations and global environmental changes. Here, we addressed the variation of florivory driven by changes in elevation and temporal flower availability. We expect decreased floral resources as elevation increases -due to environmental constraints- which may affect plant-florivore interactions. Yet, if floral resources decrease but florivores remain constant, then we may expect an increase in florivory with increasing elevation in the community. METHODS: The flowering phenology of plant individuals was recorded in the Neotropical campo rupestre vegetation, in southeastern Brazil. Damages by florivores were recorded in plots at elevations ranging from 823 to 1411 m using two response variables as a proxy for florivory: the proportion of attacked flowers per plant and the proportion of petal removal on single flowers. KEY RESULTS: Flower attack increased with elevation and damages were intensified in species with longer flowering periods. Conversely, longer flowering periods resulted in higher levels of petal removal when decreasing elevation. The temporal availability of flowers affected florivory, with the proportion of attacked flowers being more intense when there are less flowered individuals in the community. Petal removal on single flowers was intensified in plots with a larger number of individuals flowering, and with more species co-flowering. CONCLUSIONS: This study brings one of the broadest records of a commonly neglected interaction of insects feeding on floral structures, quantifying the combined effect of floral display and availability along an elevation gradient in a highly biodiverse mountaintop community. These findings contribute to filling in the gap in the understanding of florivory dynamics, focusing on a tropical mountaintop scenario facing imminent environmental changes and excessive natural resource exploitation.

13.
Philos Trans A Math Phys Eng Sci ; 382(2274): 20230101, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38826047

RESUMEN

Optical projection tomography (OPT) is a three-dimensional mesoscopic imaging modality that can use absorption or fluorescence contrast, and is widely applied to fixed and live samples in the mm-cm scale. For fluorescence OPT, we present OPT implemented for accessibility and low cost, an open-source research-grade implementation of modular OPT hardware and software that has been designed to be widely accessible by using low-cost components, including light-emitting diode (LED) excitation and cooled complementary metal-oxide-semiconductor (CMOS) cameras. Both the hardware and software are modular and flexible in their implementation, enabling rapid switching between sample size scales and supporting compressive sensing to reconstruct images from undersampled sparse OPT data, e.g. to facilitate rapid imaging with low photobleaching/phototoxicity. We also explore a simple implementation of focal scanning OPT to achieve higher resolution, which entails the use of a fan-beam geometry reconstruction method to account for variation in magnification. This article is part of the Theo Murphy meeting issue 'Open, reproducible hardware for microscopy'.

15.
Am J Emerg Med ; 78: 182-187, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38301368

RESUMEN

OBJECTIVE: Oxygen consumption (VO2), carbon dioxide generation (VCO2), and respiratory quotient (RQ), which is the ratio of VO2 to VCO2, are critical indicators of human metabolism. To seek a link between the patient's metabolism and pathophysiology of critical illness, we investigated the correlation of these values with mortality in critical care patients. METHODS: This was a prospective, observational study conducted at a suburban, quaternary care teaching hospital. Age 18 years or older healthy volunteers and patients who underwent mechanical ventilation were enrolled. A high-fidelity automation device, which accuracy is equivalent to the gold standard Douglas Bag technique, was used to measure VO2, VCO2, and RQ at a wide range of fraction of inspired oxygen (FIO2). RESULTS: We included a total of 21 subjects including 8 post-cardiothoracic surgery patients, 7 intensive care patients, 3 patients from the emergency room, and 3 healthy volunteers. This study included 10 critical care patients, whose metabolic measurements were performed in the ER and ICU, and 6 died. VO2, VCO2, and RQ of survivors were 282 +/- 95 mL/min, 202 +/- 81 mL/min, and 0.70 +/- 0.10, and those of non-survivors were 240 +/- 87 mL/min, 140 +/- 66 mL/min, and 0.57 +/- 0.08 (p = 0.34, p = 0.10, and p < 0.01), respectively. The difference of RQ was statistically significant (p < 0.01) and it remained significant when the subjects with FIO2 < 0.5 were excluded (p < 0.05). CONCLUSIONS: Low RQ correlated with high mortality, which may potentially indicate a decompensation of the oxygen metabolism in critically ill patients.


Asunto(s)
Pulmón , Respiración Artificial , Humanos , Adolescente , Estudios Prospectivos , Calorimetría Indirecta/métodos , Consumo de Oxígeno , Dióxido de Carbono/metabolismo , Enfermedad Crítica/terapia , Oxígeno
16.
Nucleic Acids Res ; 50(D1): D1109-D1114, 2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34747477

RESUMEN

Single-cell transcriptomics allows the study of immune cell heterogeneity at an unprecedented level of resolution. The Swiss portal for immune cell analysis (SPICA) is a web resource dedicated to the exploration and analysis of single-cell RNA-seq data of immune cells. In contrast to other single-cell databases, SPICA hosts curated, cell type-specific reference atlases that describe immune cell states at high resolution, and published single-cell datasets analysed in the context of these atlases. Additionally, users can privately analyse their own data in the context of existing atlases and contribute to the SPICA database. SPICA is available at https://spica.unil.ch.


Asunto(s)
Bases de Datos Genéticas , Transcriptoma/genética , Regulación de la Expresión Génica/genética , Humanos , RNA-Seq/métodos , Análisis de la Célula Individual/métodos , Transcriptoma/inmunología
17.
J Appl Toxicol ; 2024 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-38494651

RESUMEN

Plastic waste comprises polymers of different chemicals that disintegrate into nanoplastic particles (NPLs) of 1-100-nm size, thereby littering the environment and posing a threat to wildlife and human health. Research on NPL contamination has up to now focused on the ecotoxicology effects of the pollution rather than the health risks. This review aimed to speculate about the possible properties of carcinogenic and neurotoxic NPL as pollutants. Given their low-dimensional size and high surface size ratio, NPLs can easily penetrate biological membranes to cause functional and structural damage in cells. Once inside the cell, NPLs can interrupt the autophagy flux of cellular debris, alter proteostasis, provoke mitochondrial dysfunctions, and induce endoplasmic reticulum stress. Harmful metabolic and biological processes induced by NPLs include oxidative stress (OS), ROS generation, and pro-inflammatory reactions. Depending on the cell cycle status, NPLs may direct DNA damage, tumorigenesis, and lately carcinogenesis in tissues with high self-renewal capabilities like epithelia. In cells able to live the longest like neurons, NPLs could trigger neurodegeneration by promoting toxic proteinaceous aggregates, OS, and chronic inflammation. NPL genotoxicity and neurotoxicity are discussed based on the gathered evidence, when available, within the context of the intracellular uptake of these newcomer nanoparticles. In summary, this review explains how the risk evaluation of NPL pollution for human health may benefit from accurately monitoring NPL toxicokinetics and toxicodynamics at the intracellular resolution level.

18.
J Med Internet Res ; 26: e51837, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38441945

RESUMEN

BACKGROUND: Artificial intelligence chatbots such as ChatGPT (OpenAI) have garnered excitement about their potential for delegating writing tasks ordinarily performed by humans. Many of these tasks (eg, writing recommendation letters) have social and professional ramifications, making the potential social biases in ChatGPT's underlying language model a serious concern. OBJECTIVE: Three preregistered studies used the text analysis program Linguistic Inquiry and Word Count to investigate gender bias in recommendation letters written by ChatGPT in human-use sessions (N=1400 total letters). METHODS: We conducted analyses using 22 existing Linguistic Inquiry and Word Count dictionaries, as well as 6 newly created dictionaries based on systematic reviews of gender bias in recommendation letters, to compare recommendation letters generated for the 200 most historically popular "male" and "female" names in the United States. Study 1 used 3 different letter-writing prompts intended to accentuate professional accomplishments associated with male stereotypes, female stereotypes, or neither. Study 2 examined whether lengthening each of the 3 prompts while holding the between-prompt word count constant modified the extent of bias. Study 3 examined the variability within letters generated for the same name and prompts. We hypothesized that when prompted with gender-stereotyped professional accomplishments, ChatGPT would evidence gender-based language differences replicating those found in systematic reviews of human-written recommendation letters (eg, more affiliative, social, and communal language for female names; more agentic and skill-based language for male names). RESULTS: Significant differences in language between letters generated for female versus male names were observed across all prompts, including the prompt hypothesized to be neutral, and across nearly all language categories tested. Historically female names received significantly more social referents (5/6, 83% of prompts), communal or doubt-raising language (4/6, 67% of prompts), personal pronouns (4/6, 67% of prompts), and clout language (5/6, 83% of prompts). Contradicting the study hypotheses, some gender differences (eg, achievement language and agentic language) were significant in both the hypothesized and nonhypothesized directions, depending on the prompt. Heteroscedasticity between male and female names was observed in multiple linguistic categories, with greater variance for historically female names than for historically male names. CONCLUSIONS: ChatGPT reproduces many gender-based language biases that have been reliably identified in investigations of human-written reference letters, although these differences vary across prompts and language categories. Caution should be taken when using ChatGPT for tasks that have social consequences, such as reference letter writing. The methods developed in this study may be useful for ongoing bias testing among progressive generations of chatbots across a range of real-world scenarios. TRIAL REGISTRATION: OSF Registries osf.io/ztv96; https://osf.io/ztv96.


Asunto(s)
Inteligencia Artificial , Sexismo , Humanos , Femenino , Masculino , Revisiones Sistemáticas como Asunto , Lenguaje , Lingüística
19.
Sensors (Basel) ; 24(11)2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38894428

RESUMEN

Heart failure is a severe medical condition with an important worldwide incidence that occurs when the heart is unable to efficiently pump the patient's blood throughout the body. The monitoring of edema in the lower limbs is one of the most efficient ways to control the evolution of the condition. Impedance spectroscopy has been proposed as an efficient technique to monitor body volume in patients with heart failure. It is necessary to research new wearable devices for remote patient monitoring, which can be easily worn by patients in a continuous way. In this work, we design and implement new wearable textile electrodes for the monitoring of edema evolution in patients with heart failure. Impedance spectroscopy measurements were carried out in 5 healthy controls and 2 patients with heart failure using our wearable electrodes for 3 days. The results show the appropriateness of impedance spectroscopy and our wearable electrodes to monitor body volume evolution. Impedance spectroscopy is shown to be an efficient marker of the presence of edema in heart failure patients. Initial patient positive feedback was obtained for the use of the wearable device.


Asunto(s)
Espectroscopía Dieléctrica , Electrodos , Insuficiencia Cardíaca , Textiles , Dispositivos Electrónicos Vestibles , Humanos , Insuficiencia Cardíaca/fisiopatología , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/métodos , Espectroscopía Dieléctrica/métodos , Espectroscopía Dieléctrica/instrumentación , Masculino , Femenino , Persona de Mediana Edad , Edema/diagnóstico , Anciano
20.
J Fish Biol ; 104(6): 1875-1887, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38501373

RESUMEN

The short-tail yellownose skate, Zearaja brevicaudata, occurs off southern Brazil and along the Argentine continental shelf, including waters surrounding the Islas Malvinas and the upper slope, and is very frequently caught by trawl fisheries throughout its range. The age, growth, and maturity of Z. brevicaudata were investigated using 204 individuals collected by commercial fishing vessels from northern Argentina, between March 2016 and September 2019. Age was determined on a sample comprising vertebrae from 151 individuals, 60 males, ranging in size from 391 to 956 mm total length (TL), and 91 females, ranging in size from 324 to 1060 mm TL. Maximum ages determined for males and females were 22 and 29 years, respectively. A Bayesian framework was employed with a set of three candidate models to estimate growth parameters (von Bertalanffy, Gompertz, and Logistic). The von Bertalanffy model had the best fit, and the sexes showed undistinguishable growth parameters. For sexes combined, derived growth mean parameters (± S.D.) were L∞ = 1081 mm ± 64.34 mm, k = 0.09 ± 0.01 years-1, and L0 = 248 mm ± 23.52 mm. The age at maturity was estimated at 13.15 and 14.66 years for males and females, respectively.


Asunto(s)
Rajidae , Animales , Rajidae/crecimiento & desarrollo , Masculino , Femenino , Argentina , Rasgos de la Historia de Vida , Explotaciones Pesqueras , Teorema de Bayes , Brasil , Maduración Sexual , Tamaño Corporal
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