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1.
J Stroke Cerebrovasc Dis ; 33(10): 107899, 2024 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-39106923

RESUMO

BACKGROUND: Early diagnosis of previously unknown cancer (i.e., occult cancer) after an acute ischemic stroke (AIS) could result in faster initiation of cancer therapy and potentially improve clinical outcomes. Our study aimed to compare mortality rates between AIS patients with occult cancer diagnosed during the index stroke hospitalization versus those diagnosed after hospital discharge. METHODS: Among consecutive AIS patients treated at our stroke center from 2015 through 2020, we identified new cancer diagnoses made within the year after the AIS. We used multivariable Cox regression analyses to evaluate the association between the timing of occult cancer diagnosis (during the AIS hospitalization versus after discharge) and long-term survival. RESULTS: Of 3894 AIS patients with available long-term follow-up data, 59 (1.5 %) were diagnosed with a new cancer within one year after index stroke. Of these, 27 (46 %) were diagnosed during the index hospitalization and 32 (54 %) were diagnosed after discharge. During a median follow-up of 406 days (interquartile range, 89-1073), 70 % (n = 19) of patients whose cancer was diagnosed during hospitalization had died, compared to 63 % (n = 20) of patients whose cancer was diagnosed after discharge (p= 0.58). In our main multivariable model, there was no difference in long-term mortality between patient groups (adjusted hazard ratio, 1.16; 95 % confidence interval, 0.53-2.52; p= 0.71). CONCLUSIONS: In this analysis, timing of a new cancer diagnosis after AIS did not seem to influence patients' long-term survival. Given the fairly small number of included patients with previously occult cancer, larger multicenter studies are needed to confirm our results.

2.
Injury ; : 111758, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39098571

RESUMO

INTRODUCTION: Older patients are expected to comprise 40 % of trauma admissions in the next 30 years. The use of whole blood (WB) has shown promise in improving mortality while lowering the utilization of blood products. However, the use of WB in older trauma patients has not been examined. The objective of our study is to determine the safety and efficacy of a WB first transfusion strategy in injured older patients. METHODS: Older trauma patients, defined as age ≥55 years old, were reviewed from March 2016-November 2021. Patients that received a WB first resuscitation strategy were compared to those that received a ratio based component strategy. Demographics as well as complications rates, blood product transfusion volumes, and mortality were evaluated. Univariate and multivariable analysis was used to determine independent predictors of mortality. RESULTS: There were 388 older trauma patients that received any blood products during the study period. A majority of patients received a WB first resuscitation strategy (83 %). Compared to patients that received component therapy, patients that received WB first were more likely female, less likely to have a penetrating mechanism, and had a slightly lower injury severity score. The-30 day mortality rate was comparable (WB 36% vs component 37 %, p = 0.914). While rates of AKI were slightly higher in those that received WB, this did not result in increased rates of renal replacement therapy (3 % vs 2 %, p = 1). Further, compared to patients that received components, patients that were resuscitated with a WB first strategy significantly utilized lower median volumes of platelets (0 mL vs 197 mL, p < 0.001), median volumes of plasma (0 mL vs 1253 mL, p < 0.001, and median total volume of blood products (1000 mL vs 2859 mL, p < 0.001). CONCLUSION: The use of WB in the older trauma patient appears safe, with mortality and complication rates comparable to component therapy. Blood product utilization is significantly less in those that are resuscitated with WB first.

3.
Free Radic Biol Med ; 224: 1-8, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39147069

RESUMO

We re-examined the reported increase in mitochondrial ROS production during acute hypoxia in cells. Using the Amplex Ultrared/horseradish peroxidase assay we found a decrease, not increase, in hydrogen peroxide release from HEK293 cells under acute hypoxia, at times ranging from 1 min to 3 h. The rates of superoxide/hydrogen peroxide production from each of the three major sites (site IQ in complex I and site IIIQo in complex III in mitochondria, and NADH oxidases (NOX) in the cytosol) were decreased to the same extent by acute hypoxia, with no change in the cells' ability to degrade added hydrogen peroxide. A similar decrease in ROS production under acute hypoxia was found using the diacetyldichlorofluorescein assay. Using a HIF1α reporter cell line we confirmed earlier observations that suppression of superoxide production by site IIIQo decreases HIF1α expression, and found similar effects of suppressing site IQ or NOX. We conclude that increased mitochondrial ROS do not drive the response of HIF1α to acute hypoxia, but suggest that cytosolic H2O2 derived from site IQ, site IIIQo and NOX in cells is necessary to permit HIF1α stabilization by other signals.

4.
NPJ Precis Oncol ; 8(1): 178, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138341

RESUMO

Enabling the examination of cell-cell relationships in tissue, spatially resolved omics technologies have revolutionised our perspectives on cancer biology. Clinically, the development of immune checkpoint inhibitors (ICI) has advanced cancer therapeutics. However, a major challenge of effective implementation is the identification of predictive biomarkers of response. In this review we examine the potential added predictive value of spatial biomarkers of response to ICI beyond current clinical benchmarks.

5.
Int J Mol Sci ; 25(15)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39125680

RESUMO

Inflammatory processes in the brain can exert important neuroprotective functions. However, in neurological and psychiatric disorders, it is often detrimental due to chronic microglial over-activation and the dysregulation of cytokines and chemokines. Growing evidence indicates the emerging yet prominent pathophysiological role of neuroinflammation in the development and progression of these disorders. Despite recent advances, there is still a pressing need for effective therapies, and targeting neuroinflammation is a promising approach. Therefore, in this study, we investigated the anti-neuroinflammatory potential of a marketed and quantified proprietary herbal extract of Ginkgo biloba leaves called EGb 761 (10-500 µg/mL) in BV2 microglial cells stimulated by LPS (10 ng/mL). Our results demonstrate significant inhibition of LPS-induced expression and release of cytokines tumor necrosis factor-α (TNF-α) and Interleukin 6 (IL-6) and chemokines C-X-C motif chemokine ligand 2 (CXCL2), CXCL10, c-c motif chemokine ligand 2 (CCL2) and CCL3 in BV2 microglial cells. The observed effects are possibly mediated by the mitogen-activated protein kinases (MAPK), p38 MAPK and ERK1/2, as well as the protein kinase C (PKC) and the nuclear factor (NF)-κB signaling cascades. The findings of this in vitro study highlight the anti-inflammatory properties of EGb 761 and its therapeutic potential, making it an emerging candidate for the treatment of neuroinflammatory diseases and warranting further research in pre-clinical and clinical settings.


Assuntos
Anti-Inflamatórios , Ginkgo biloba , Lipopolissacarídeos , Microglia , Extratos Vegetais , Ginkgo biloba/química , Microglia/efeitos dos fármacos , Microglia/metabolismo , Extratos Vegetais/farmacologia , Animais , Camundongos , Anti-Inflamatórios/farmacologia , Linhagem Celular , Citocinas/metabolismo , NF-kappa B/metabolismo , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Extrato de Ginkgo
6.
Eur Phys J C Part Fields ; 84(8): 784, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39130092

RESUMO

The multi-staged XENON program at INFN Laboratori Nazionali del Gran Sasso aims to detect dark matter with two-phase liquid xenon time projection chambers of increasing size and sensitivity. The XENONnT experiment is the latest detector in the program, planned to be an upgrade of its predecessor XENON1T. It features an active target of 5.9 tonnes of cryogenic liquid xenon (8.5 tonnes total mass in cryostat). The experiment is expected to extend the sensitivity to WIMP dark matter by more than an order of magnitude compared to XENON1T, thanks to the larger active mass and the significantly reduced background, improved by novel systems such as a radon removal plant and a neutron veto. This article describes the XENONnT experiment and its sub-systems in detail and reports on the detector performance during the first science run.

7.
Cancer Res Commun ; 4(8): 1978-1990, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39015091

RESUMO

Emerging evidence supports the important role of the tumor microbiome in oncogenesis, cancer immune phenotype, cancer progression, and treatment outcomes in many malignancies. In this study, we investigated the metastatic melanoma tumor microbiome and its potential roles in association with clinical outcomes, such as survival, in patients with metastatic disease treated with immune checkpoint inhibitors (ICI). Baseline tumor samples were collected from 71 patients with metastatic melanoma before treatment with ICIs. Bulk RNA sequencing (RNA-seq) was conducted on the formalin-fixed, paraffin-embedded and fresh frozen tumor samples. Durable clinical benefit (primary clinical endpoint) following ICIs was defined as overall survival >24 months and no change to the primary drug regimen (responders). We processed RNA-seq reads to carefully identify exogenous sequences using the {exotic} tool. The age of the 71 patients with metastatic melanoma ranged from 24 to 83 years, 59% were male, and 55% survived >24 months following the initiation of ICI treatment. Exogenous taxa were identified in the tumor RNA-seq, including bacteria, fungi, and viruses. We found differences in gene expression and microbe abundances in immunotherapy-responsive versus nonresponsive tumors. Responders showed significant enrichment of bacteriophages in the phylum Uroviricota, and nonresponders showed enrichment of several bacteria, including Campylobacter jejuni. These microbes correlated with immune-related gene expression signatures. Finally, we found that models for predicting prolonged survival with immunotherapy using both microbe abundances and gene expression outperformed models using either dataset alone. Our findings warrant further investigation and potentially support therapeutic strategies to modify the tumor microbiome in order to improve treatment outcomes with ICIs. SIGNIFICANCE: We analyzed the tumor microbiome and interactions with genes and pathways in metastatic melanoma treated with immunotherapy and identified several microbes associated with immunotherapy response and immune-related gene expression signatures. Machine learning models that combined microbe abundances and gene expression outperformed models using either dataset alone in predicting immunotherapy responses.


Assuntos
Inibidores de Checkpoint Imunológico , Melanoma , Microbiota , Humanos , Melanoma/tratamento farmacológico , Melanoma/microbiologia , Melanoma/imunologia , Melanoma/secundário , Masculino , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Feminino , Pessoa de Meia-Idade , Idoso , Adulto , Microbiota/efeitos dos fármacos , Idoso de 80 Anos ou mais , Adulto Jovem , Resultado do Tratamento , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/microbiologia , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Metástase Neoplásica , Prognóstico
8.
J Natl Compr Canc Netw ; 22(5): 290-298, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-39019054

RESUMO

The NCCN Guidelines for Cutaneous Melanoma (termed Melanoma: Cutaneous) provide multidisciplinary recommendations for diagnostic workup, staging, and treatment of patients. These NCCN Guidelines Insights focus on the update to neoadjuvant systemic therapy options and summarize the new clinical data evaluated by the NCCN panel for the recommended therapies in Version 2.2024 of the NCCN Guidelines for Cutaneous Melanoma.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Melanoma/terapia , Melanoma/diagnóstico , Melanoma/patologia , Neoplasias Cutâneas/terapia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Estadiamento de Neoplasias , Oncologia/normas , Oncologia/métodos
9.
ESC Heart Fail ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39041459

RESUMO

AIMS: We aim to evaluate change in the use of prognostic guideline-directed medical therapies (GDMTs) for heart failure (HF) before and after a cancer diagnosis as well as the matched non-cancer controls, including renin-angiotensin-system inhibitors (RASIs), beta-blockers, and mineralocorticoid receptor antagonists (MRAs). METHODS AND RESULTS: We conducted a longitudinal study in patients with HF in the UK Clinical Practice Research Datalink between 2005 and 2021. We selected patients with probable HF with reduced ejection fraction (HFrEF) based on diagnostic and prescription records. We described the longitudinal trends in the use and dosing of GDMTs before and after receiving an incident cancer diagnosis. HF patients with cancer were matched with a 1:1 ratio to HF patients without cancer to investigate the association between cancer diagnosis and treatment adherence, persistence, initiation, and dose titration as odds ratios (ORs) with 95% confidence intervals (CIs) using multivariable logistic regression models. Of 8504 eligible HFrEF patients with incident cancer, 4890 were matched to controls without cancer. The mean age was 75.7 (±8.4) years and 73.9% were male. In the 12 months following a cancer diagnosis, patients experienced reductions in the use and dosing of GDMT. Compared with the non-cancer controls, patients with cancer had higher risks for poor adherence for all three medication classes (RASIs: OR = 1.51, 95% CI = 1.35-1.68; beta-blockers: OR = 1.22, 95% CI = 1.08-1.37; MRAs: OR = 1.31, 95% CI = 1.08-1.59) and poor persistence (RASIs: OR = 2.04, 95% CI = 1.75-2.37; beta-blockers: OR = 1.35, 95% CI = 1.12-1.63; MRAs: OR = 1.49, 95% CI = 1.16-1.93), and higher risks for dose down-titration for RASIs (OR = 1.69, 95% CI = 1.40-2.04) and beta-blockers (OR = 1.31, 95% CI = 1.05-1.62). Cancer diagnosis was not associated with treatment initiation or dose up-titration. Event rates for HF hospitalization and mortality were higher in patients with poor adherence or persistence to GDMTs. CONCLUSIONS: Following a cancer diagnosis, patients with HFrEF were more likely to have reduced use of GDMTs for HF.

10.
Clin J Sport Med ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38975933

RESUMO

OBJECTIVE: Ultramarathon runners are a unique patient population who have been shown to have a lower rate of severe chronic medical conditions. This study aimed to determine the effect that COVID-19 infection has had on this population and their running behavior. DESIGN: The Ultrarunners Longitudinal TRAcking (ULTRA) Study is a large longitudinal study of ultramarathon runners. Questions on health status, running behavior, and COVID-19 infection were included in the most recent survey. SETTING: Community survey. PARTICIPANTS: Seven hundred thirty-four ultramarathon runners participated in the study. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Personal, exercise, and COVID-19 infection history. RESULTS: 52.7% of study participants reported having been symptomatic from a COVID-19 infection, with 6.7% testing positive multiple times. Participants required a total of 4 days of hospitalization. The most common symptoms included fever (73.6%), fatigue (68.5%), sore throat (68.2%), runny nose (67.7%), and cough (67.4%). Cardiovascular symptoms, which are of particular interest in the running population, included shortness of breath (46.3%), tachycardia (44.7%), chest pain (36.2%), and wheezing (33.3%). A total of 50 subjects (6.8%) reported long COVID (symptoms lasting more than 12 weeks). CONCLUSIONS: Severe COVID-19 infection has been rare in this population of ultramarathon runners, although symptomatic infection that affects running is common. To support the well-being of this group of highly active athletes, clinicians should appreciate that cardiovascular symptoms are common and the long-term significance of these symptoms in runners is unknown. LEVEL OF EVIDENCE: Level 2 prospective study.

11.
Int J Mol Sci ; 25(14)2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39062841

RESUMO

Pre-treatment genotyping of four well-characterized toxicity risk-variants in the dihydropyrimidine dehydrogenase gene (DPYD) has been widely implemented in Europe to prevent serious adverse effects in cancer patients treated with fluoropyrimidines. Current genotyping practices are largely limited to selected commonly studied variants and are unable to determine phasing when more than one variant allele is detected. Recent evidence indicates that common DPYD variants modulate the functional impact of deleterious variants in a phase-dependent manner, where a cis- or a trans-configuration translates into different toxicity risks and dosing recommendations. DPYD is a large gene with 23 exons spanning nearly a mega-base of DNA, making it a challenging candidate for full-gene sequencing in the diagnostic setting. Herein, we present a time- and cost-efficient long-read sequencing approach for capturing the complete coding region of DPYD. We demonstrate that this method can reliably produce phased genotypes, overcoming a major limitation with current methods. This method was validated using 21 subjects, including two cancer patients, each of whom carried multiple DPYD variants. Genotype assignments showed complete concordance with conventional approaches. Furthermore, we demonstrate that the method is robust to technical challenges inherent in long-range sequencing of PCR products, including reference alignment bias and PCR chimerism.


Assuntos
Di-Hidrouracila Desidrogenase (NADP) , Genótipo , Técnicas de Genotipagem , Di-Hidrouracila Desidrogenase (NADP)/genética , Humanos , Técnicas de Genotipagem/métodos , Análise de Sequência de DNA/métodos , Neoplasias/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Polimorfismo de Nucleotídeo Único , Alelos
13.
J Neural Eng ; 21(4)2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39084245

RESUMO

Objective.Optogenetics allows the manipulation of neural circuitsin vivowith high spatial and temporal precision. However, combining this precision with control over a significant portion of the brain is technologically challenging (especially in larger animal models).Approach.Here, we have developed, optimised, and testedin vivo, the Utah Optrode Array (UOA), an electrically addressable array of optical needles and interstitial sites illuminated by 181µLEDs and used to optogenetically stimulate the brain. The device is specifically designed for non-human primate studies.Main results.Thinning the combinedµLED and needle backplane of the device from 300µm to 230µm improved the efficiency of light delivery to tissue by 80%, allowing lowerµLED drive currents, which improved power management and thermal performance. The spatial selectivity of each site was also improved by integrating an optical interposer to reduce stray light emission. These improvements were achieved using an innovative fabrication method to create an anodically bonded glass/silicon substrate with through-silicon vias etched, forming an optical interposer. Optical modelling was used to demonstrate that the tip structure of the device had a major influence on the illumination pattern. The thermal performance was evaluated through a combination of modelling and experiment, in order to ensure that cortical tissue temperatures did not rise by more than 1 °C. The device was testedin vivoin the visual cortex of macaque expressing ChR2-tdTomato in cortical neurons.Significance.It was shown that the UOA produced the strongest optogenetic response in the region surrounding the needle tips, and that the extent of the optogenetic response matched the predicted illumination profile based on optical modelling-demonstrating the improved spatial selectivity resulting from the optical interposer approach. Furthermore, different needle illumination sites generated different patterns of low-frequency potential activity.


Assuntos
Optogenética , Animais , Optogenética/métodos , Optogenética/instrumentação , Estimulação Luminosa/métodos , Estimulação Luminosa/instrumentação , Desenho de Equipamento/métodos , Macaca mulatta , Luz , Masculino
14.
Chem Sci ; 15(27): 10541-10546, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38994423

RESUMO

Dissectol A is a rearranged terpene glycoside isolated from several flowering plants. Starting from glucose, the densely functionalized bicyclic structure has been prepared via site-selective oxidation and an intramolecular allylic alkylation reaction with an enediolate as the nucleophile. Despite earlier reports, dissectol A is not effective at inhibiting DevRS signaling in whole-cell Mycobacterium tuberculosis and does not inhibit growth of the bacterium.

15.
Int J Cancer ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39001563

RESUMO

Despite advancements in treating cutaneous melanoma, patients with acral and mucosal (A/M) melanomas still have limited therapeutic options and poor prognoses. We analyzed 156 melanomas (101 cutaneous, 28 acral, and 27 mucosal) using the Foundation One cancer-gene specific clinical testing platform and identified new, potentially targetable genomic alterations (GAs) in specific anatomic sites of A/M melanomas. Using novel pre-clinical models of A/M melanoma, we demonstrate that several GAs and corresponding oncogenic pathways associated with cutaneous melanomas are similarly targetable in A/M melanomas. Other alterations, including MYC and CRKL amplifications, were unique to A/M melanomas and susceptible to indirect targeting using the BRD4 inhibitor JQ1 or Src/ABL inhibitor dasatinib, respectively. We further identified new, actionable A/M-specific alterations, including an inactivating NF2 fusion in a mucosal melanoma responsive to dasatinib in vivo. Our study highlights new molecular differences between cutaneous and A/M melanomas, and across different anatomic sites within A/M, which may change clinical testing and treatment paradigms for these rare melanomas.

16.
Am J Surg ; 238: 115820, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-39059340

RESUMO

BACKGROUND: It has previously been demonstrated that Thrombelastography(TEG) angle may be associated with recurrence and survival in pancreas cancer in a cohort of patients operated on at the University of Colorado in 2016-2017. Now approaching 10 years of follow-up, we revisit these associations and strengthen these claims with multivariate analysis. METHODS: Retrospective chart review was performed. Statistical analysis was conducted using STATA. Receiver operating characteristic(ROC) curves identified the performance of angle for predicting recurrence&survival. Unadjusted and adjusted cox regression models were used to identify significant predictors of these outcomes. RESULTS: 47 patients were included with median follow-up of 29.6 months. ROC curves for angle predicting recurrence and survival identified a cutoff of 44.5°. KM curves demonstrated that patients above the cutoff were more likely to recur(90%vs46 â€‹%,p â€‹= â€‹0.001) and less likely to survive(16%vs56 â€‹%,p â€‹= â€‹0.001). Angle remained significant on multivariate analyses (HR recurrence:3.64[1.32-10.25],HR survival:3.80[1.38-10.46]). CONCLUSIONS: TEG angle is independently associated with disease recurrence and overall survival in pancreas cancer. This may be identifying virulent tumor biology, but further studies are required. A prospective study is underway.

17.
Biochim Biophys Acta Mol Cell Res ; 1871(7): 119796, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39038610

RESUMO

Pyruvate kinase M2 (PKM2) is a key glycolytic enzyme interacting with the inositol 1,4,5-trisphosphate receptor (IP3R). This interaction suppresses IP3R-mediated cytosolic [Ca2+] rises. As PKM2 exists in monomeric, dimeric and tetrameric forms displaying different properties including catalytic activity, we investigated the molecular determinants of PKM2 enabling its interaction with IP3Rs. Treatment of HeLa cells with TEPP-46, a compound stabilizing the tetrameric form of PKM2, increased both its catalytic activity and the suppression of IP3R-mediated Ca2+ signals. Consistently, in PKM2 knock-out HeLa cells, PKM2C424L, a tetrameric, highly active PKM2 mutant, but not inactive PKM2K270M or the less active PKM2K305Q, suppressed IP3R-mediated Ca2+ release. Surprisingly, however, in vitro assays did not reveal a direct interaction between purified PKM2 and either the purified Fragment 5 of IP3R1 (a.a. 1932-2216) or the therein located D5SD peptide (a.a. 2078-2098 of IP3R1), the presumed interaction sites of PKM2 on the IP3R. Moreover, on-nucleus patch clamp of heterologously expressed IP3R1 in DT40 cells devoid of endogenous IP3Rs did not reveal any functional effect of purified wild-type PKM2, mutant PKM2 or PKM1 proteins. These results indicate that an additional factor mediates the regulation of the IP3R by PKM2 in cellulo. Immunoprecipitation of GRP75 using HeLa cell lysates co-precipitated IP3R1, IP3R3 and PKM2. Moreover, the D5SD peptide not only disrupted PKM2:IP3R, but also PKM2:GRP75 and GRP75:IP3R interactions. Our data therefore support a model in which catalytically active, tetrameric PKM2 suppresses Ca2+ signaling via the IP3R through a multiprotein complex involving GRP75.

18.
Nanotechnology ; 35(39)2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38955132

RESUMO

Electron backscatter diffraction and cathodoluminescence are complementary scanning electron microscopy modes widely used in the characterisation of semiconductor films, respectively revealing the strain state of a crystalline material and the effect of this strain on the light emission from the sample. Conflicting beam, sample and detector geometries have meant it is not generally possible to acquire the two signals together during the same scan. Here, we present a method of achieving this simultaneous acquisition, by collecting the light emission through a transparent sample substrate. We apply this combination of techniques to investigate the strain field and resultant emission wavelength variation in a deep-ultraviolet micro-LED. For such compatible samples, this approach has the benefits of avoiding image alignment issues and minimising beam damage effects.

19.
Fish Shellfish Immunol ; 151: 109740, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38960104

RESUMO

ß-glucans are carbohydrates present in the cell wall of many fungi, which are often used as immunostimulants in feeds for farmed species. Their capacity to activate innate immune responses directly acting on innate cell populations has been widely documented in fish. However, whether they can affect the functionality of adaptive immune cells has been scarcely explored. In this context, in the current work, we have determined the effects of ß-glucans on rainbow trout blood IgM+ B cells in the presence or absence of 2,4,6-trinitrophenyl hapten conjugated to lipopolysaccharide (TNP-LPS), a model antigen. For this, rainbow trout peripheral blood leukocytes were incubated with different doses of ß-glucans or media alone in the presence or absence of TNP-LPS for 48 h. The size, levels of expression of surface MHC II, antigen processing and phagocytic capacities and proliferation of IgM+ B cells were then studied by flow cytometry. The number of IgM-secreting cells in the cultures was also estimated by ELISpot. ß-glucans significantly decreased the levels of surface MHC II expression and the antigen processing capacities of these cells, especially in the presence of TNP-LPS, while they increased their phagocytic activity. On their own, ß-glucans slightly activated the proliferation of IgM+ B cells but reduced that induced by TNP-LPS. In contrast, ß-glucans significantly increased the number of cells secreting IgM in the cultures. This effect of ß-glucans on the IgM-secreting capacity of B cells was also confirmed through a feeding experiment, in which the IgM-secreting capacity of blood leukocytes obtained from fish fed a ß-glucan-supplemented diet for one month was compared to that of leukocytes obtained from fish fed a control diet. Altogether, these findings contribute to increase our knowledge regarding the effects of ß-glucans on fish adaptive responses.


Assuntos
Linfócitos B , Imunoglobulina M , Oncorhynchus mykiss , beta-Glucanas , Animais , Oncorhynchus mykiss/imunologia , beta-Glucanas/farmacologia , beta-Glucanas/administração & dosagem , Imunoglobulina M/imunologia , Linfócitos B/imunologia , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/administração & dosagem , Lipopolissacarídeos/farmacologia , Imunidade Inata/efeitos dos fármacos , Suplementos Nutricionais/análise
20.
Science ; 384(6703): eadl0370, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38935708

RESUMO

Innate lymphoid cells (ILCs) and adaptive T lymphocytes promote tissue homeostasis and protective immune responses. Their production depends on the transcription factor GATA3, which is further elevated specifically in ILC2s and T helper 2 cells to drive type-2 immunity during tissue repair, allergic disorders, and anti-helminth immunity. The control of this crucial up-regulation is poorly understood. Using CRISPR screens in ILCs we identified previously unappreciated myocyte-specific enhancer factor 2d (Mef2d)-mediated regulation of GATA3-dependent type-2 lymphocyte differentiation. Mef2d-deletion from ILC2s and/or T cells specifically protected against an allergen lung challenge. Mef2d repressed Regnase-1 endonuclease expression to enhance IL-33 receptor production and IL-33 signaling and acted downstream of calcium-mediated signaling to translocate NFAT1 to the nucleus to promote type-2 cytokine-mediated immunity.


Assuntos
Fator de Transcrição GATA3 , Imunidade Inata , Interleucina-33 , Fatores de Transcrição MEF2 , Fatores de Transcrição NFATC , Pneumonia , Células Th2 , Animais , Camundongos , Fatores de Transcrição MEF2/metabolismo , Fatores de Transcrição MEF2/genética , Células Th2/imunologia , Interleucina-33/metabolismo , Fatores de Transcrição NFATC/metabolismo , Pneumonia/imunologia , Fator de Transcrição GATA3/metabolismo , Fator de Transcrição GATA3/genética , Camundongos Endogâmicos C57BL , Diferenciação Celular , Sinalização do Cálcio , Hipersensibilidade/imunologia , Pulmão/imunologia , Alérgenos/imunologia , Linfócitos/imunologia , Proteína 1 Semelhante a Receptor de Interleucina-1
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