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1.
J Hepatol ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38548067

RESUMO

BACKGROUND: Non-invasive scores have been proposed to identify patients with fibrotic, metabolic dysfunction associated steatohepatitis (MASH), who are at the highest risk of progression to complications of cirrhosis and may benefit from pharmacologic treatments. However, data in type 2 diabetes (T2DM) patients are lacking. The aim of this multicenter prospective study was to compare head-to-head FAST (FibroScan-aspartate aminotransferase [AST]), MAST (magnetic resonance imaging [MRI]-AST), MEFIB (magnetic resonance elastography [MRE] plus FIB-4), and FNI (fibrotic NASH index) for detecting fibrotic MASH in T2DM patients. METHODS: 330 T2DM outpatients with biopsy-proven metabolic dysfunction associated steatotic liver disease (MASLD) from the QUID-NASH study (NCT03634098), who underwent FibroScan, MRI-PDFF and MRE at the time of liver biopsy (LB) were studied. The main outcome was fibrotic MASH, defined as NAS ≥ 4 (with at least one point each) and fibrosis stage ≥ 2 (centrally reviewed). RESULTS: 245 patients (median age 59 years, male 65%, BMI 31 kg/m2; fibrotic MASH 39%) had all data available for scores comparison. FAST and MAST had similar accuracy (AUROCs 0.81 vs. 0.79, p = 0.41) but outperformed FNI (0.74; p = 0.01) and MEFIB (0.68; p < 0.0001). When using original cutoffs, MAST outperformed FAST, MEFIB and FNI when comparing the percentage of correctly classified patients, in whom LB would be avoided (69% vs. 48%, 46%, 39%, respectively; p < 0.001). When using cutoffs specific to our population, FAST outperformed FNI and MAST (56% vs. 40%, and 38%, respectively; p < 0.001). CONCLUSION: Our findings show that FAST, MAST, MEFIB and FNI are accurate non-invasive tools to identify T2DM patients with fibrotic MASH in secondary/tertiary diabetes clinics. Cutoffs adapted to T2DM population should be considered. TRIAL REGISTRATION NUMBER: NCT03634098.

2.
PLoS One ; 19(3): e0297159, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38466696

RESUMO

INTRODUCTION: In 2012, the World Health Organization revised treatment guidelines for childhood pneumonia with lower chest wall indrawing (LCWI) but no 'danger signs', to recommend home-based treatment. We analysed data from children hospitalized with LCWI pneumonia in the Pneumonia Etiology Research for Child Health (PERCH) study to identify sub-groups with high odds of mortality, who might continue to benefit from hospital management but may not be admitted by staff implementing the 2012 guidelines. We compare the proportion of deaths identified using the criteria in the 2012 guidelines, and the proportion of deaths identified using an alternative set of criteria from our model. METHODS: PERCH enrolled a cohort of 2189 HIV-negative children aged 2-59 months who were admitted to hospital with LCWI pneumonia (without obvious cyanosis, inability to feed, vomiting, convulsions, lethargy or head nodding) between 2011-2014 in Kenya, Zambia, South Africa, Mali, The Gambia, Bangladesh, and Thailand. We analysed risk factors for mortality among these cases using predictive logistic regression. Malnutrition was defined as mid-upper-arm circumference <125mm or weight-for-age z-score <-2. RESULTS: Among 2189 cases, 76 (3·6%) died. Mortality was associated with oxygen saturation <92% (aOR 3·33, 1·99-5·99), HIV negative but exposed status (4·59, 1·81-11·7), moderate or severe malnutrition (6·85, 3·22-14·6) and younger age (infants compared to children 12-59 months old, OR 2·03, 95%CI 1·05-3·93). At least one of three risk factors: hypoxaemia, HIV exposure, or malnutrition identified 807 children in this population, 40% of LCWI pneumonia cases and identified 86% of the children who died in hospital (65/76). Risk factors identified using the 2012 WHO treatment guidelines identified 66% of the children who died in hospital (n = 50/76). CONCLUSIONS: Although it focuses on treatment failure in hospital, this study supports the proposal for better risk stratification of children with LCWI pneumonia. Those who have hypoxaemia, any malnutrition or those who were born to HIV positive mothers, experience poorer outcomes than other children with LCWI pneumonia. Consistent identification of these risk factors should be prioritised and children with at least one of these risk factors should not be managed in the community.


Assuntos
Infecções por HIV , Desnutrição , Pneumonia , Lactente , Criança , Humanos , Pré-Escolar , Pneumonia/epidemiologia , Hospitalização , Desnutrição/complicações , Infecções por HIV/complicações , Hipóxia/etiologia
3.
PLoS One ; 19(2): e0297741, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38358974

RESUMO

Prior to the next generation sequencing and characterization of the tumor genome landscape, mutations in the SWI/SNF chromatin remodeling complex and the KEAP1-NRF2 signaling pathway were underappreciated. While these two classes of mutations appeared to independently contribute to tumor development, recent reports have demonstrated a mechanistic link between these two regulatory mechanisms in specific cancer types and cell models. In this work, we expand upon these data by exploring the relationship between mutations in BAF and PBAF subunits of the SWI/SNF complex and activation of NRF2 signal transduction across many cancer types. ARID1A/B mutations were strongly associated with NRF2 transcriptional activity in head and neck squamous carcinomas (HNSC). Many additional tumor types showed significant association between NRF2 signaling and mutation of specific components of the SWI/SNF complex. Different effects of BAF and PBAF mutations on the polarity of NRF2 signaling were observed. Overall, our results support a context-dependent functional link between SWI/SNF and NRF2 mutations across human cancers and implicate ARID1A inactivation in HPV-negative HNSC in promoting tumor progression and survival through activation of the KEAP1-NRF2 signaling pathway. The tumor-specific effects of these mutations open a new area of study for how mutations in the KEAP1-NRF2 pathway and the SWI/SNF complex contribute to cancer.


Assuntos
Proteínas de Ligação a DNA , Neoplasias de Cabeça e Pescoço , Fator 2 Relacionado a NF-E2 , Fatores de Transcrição , Humanos , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Neoplasias de Cabeça e Pescoço/genética , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Mutação , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Transdução de Sinais/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
4.
Cancer Res Commun ; 4(2): 487-495, 2024 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-38335300

RESUMO

Aberrant activation of the NRF2/NFE2L2 transcription factor commonly occurs in head and neck squamous cell carcinomas (HNSCC). Mouse model studies have shown that NRF2 activation alone does not result in cancer. When combined with classic oncogenes and at the right dose, NRF2 activation promotes tumor initiation and progression. Here we deleted the tumor suppressor genes p16INK4A and p53 (referred to as CP mice), which are commonly lost in human HNSCC, in the presence of a constitutively active NRF2E79Q mutant (CPN mice). NRF2E79Q expression in CPN mice resulted in squamous cell hyperplasia or dysplasia with hyperkeratosis in the esophagus, oropharynx, and forestomach. In addition, CPN mice displayed oral cavity squamous cell carcinoma (OSCC); CP mice bearing wild-type NRF2 expression did not develop oral cavity hyperplasia, dysplasia or OSCC. In both CP and CPN mice, we also observed predominantly abdominal sarcomas and carcinomas. Our data show that in the context of p53 and p16 tumor suppressor loss, NRF2 activation serves oncogenic functions to drive OSCC. CPN mice represent a new model for OSCC that closely reflects the genetics of human HNSCC. SIGNIFICANCE: Human squamous cancers frequently show constitutive NRF2 activation, associated with poorer outcomes and resistance to multiple therapies. Here, we report the first activated NRF2-driven and human-relevant mouse model of squamous cell carcinoma that develops in the background of p16 and p53 loss. The availability of this model will lead to a clearer understanding of how NRF2 contributes to the initiation, progression, and therapeutic response of OSCC.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Animais , Humanos , Camundongos , Carcinoma de Células Escamosas/genética , Modelos Animais de Doenças , Neoplasias de Cabeça e Pescoço/genética , Hiperplasia/genética , Neoplasias Bucais/genética , Fator 2 Relacionado a NF-E2/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Proteína Supressora de Tumor p53/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo
5.
J Grad Med Educ ; 16(1): 88-89, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38304586
6.
Eur Radiol ; 34(3): 1461-1470, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37658893

RESUMO

OBJECTIVES: To evaluate the association between fat infiltration in skeletal muscles (myosteatosis) and hepatocellular carcinoma (HCC) in patients with non-alcoholic fatty liver disease (NAFLD). METHODS: In a cross-sectional cohort of 72 histologically proven NAFLD patients (n = 38 with non-alcoholic steatohepatitis; NASH), among which 20 had HCC diagnosed on biopsy, we used proton density fat fraction (PDFF) at MRI to evaluate myosteatosis in skeletal muscles (mean fat fraction and first order radiomic-based pattern) at the third lumbar level, namely in erector spinae (ES), quadratus lumborum (QL), psoas, oblique, and rectus muscles. RESULTS: PDFFES was 70% higher in patients with HCC when compared to those without HCC (9.6 ± 5.5% versus 5.7 ± 3.0%, respectively, p < 0.001). In multivariate logistic regression, PDFFES was a significant predictor of the presence of HCC (AUC = 0.72, 95% CI 0.57-0.86, p = 0.002) independently from age, sex, visceral fat area, and liver fibrosis stage (all p < 0.05). The relationship between PDFFES and HCC was exacerbated in patients with NASH (AUC = 0.79, 95% CI 0.63-0.86, p = 0.006). In patients with NASH, radiomics features of heterogeneity such as energy and entropy in any of the paraspinal muscles (i.e., ES, QL, or psoas) were independent predictors of HCC. EnergyES identified patients with HCC (n = 13) in the NASH population with AUC = 0.92 (95% CI 0.82-1.00, p < 0.001). CONCLUSION: In patients with NAFLD, and more specifically in those with NASH, the degree and heterogeneity of myosteatosis is independently associated with HCC irrespective of liver fibrosis stage. CLINICAL RELEVANCE STATEMENT: Our data suggest that myosteatosis could be used as a biomarker of HCC in the ever-expanding NAFLD population and pave the way for further investigation in longitudinal studies. KEY POINTS: • HCC in patients with non-alcoholic fatty liver disease, and more specifically in those with non-alcoholic steatohepatitis, is independently associated with severe fatty infiltration (myosteatosis) of paravertebral skeletal muscles. • Association between myosteatosis and HCC is independent from liver fibrosis stage. • Histogram-based radiomics features of myosteatosis predicts the risk of HCC in patients with non-alcoholic steatohepatitis.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/patologia , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Estudos Transversais , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Fígado/patologia , Cirrose Hepática/patologia , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/patologia
7.
J Econ Entomol ; 117(1): 43-57, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38092702

RESUMO

The western honey bee (Apis mellifera L.) is the most globally used managed pollinator species, but it can have limited pollinating activity on nectariferous crops displaying anthers isolated from stigmas, i.e., when anthers are spatially or temporally separated from stigma within or between flowers. We supplemented honey bee colonies with pollen in the combs or in paste form laid on top of the hive frames to test if these treatments could reduce their pollen foraging and increase their pollinating activity in a monoecious and nectariferous cultivar of cantaloupe melon (Cucumis melo L.), in comparison with control colonies not supplemented. We recorded the pollen forager density per flower, the number of pollen grains deposited per stigma and their resulting fruit set, seed set and fruit mass, before and after the colony pollen supplementations. The number of pollen grains deposited by honey bees on stigmas increased gradually after pollen supplementation in the combs. But pollen foraging decreased only moderately, and no effect could be observed on any yield component except the seed set. On the other hand, there was no effect of the pollen paste laid on top of the frames either on stigmatic pollen loads, on colony pollen foraging or on any yield component. Supplementing honey bee colonies with pollen in the combs can therefore be an effective means for increasing their pollinating activity in nectariferous crops displaying anthers isolated from stigmas, e.g., Amaryllidaceae, Apiaceae, Cucurbitaceae, avocado, all hybrid seed productions. The context for the potential use of pollen substitutes is discussed.


Assuntos
Cucurbitaceae , Himenópteros , Abelhas , Animais , Frutas , Sementes , Pólen , Produtos Agrícolas , Polinização
8.
J Magn Reson Imaging ; 59(1): 97-107, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37158252

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is increasing worldwide and is a growing cause of liver cirrhosis and cancer. The performance of the magnetic resonance elastography (MRE) visco-elastic parameters in diagnosing progressive forms of NAFLD, including nonalcoholic steatohepatitis (NASH) and substantial fibrosis (F ≥ 2), needs to be clarified. PURPOSE: To assess the value of three-dimensional MRE visco-elastic parameters as markers of NASH and substantial fibrosis in mice with NAFLD. STUDY TYPE: Prospective. ANIMAL MODEL: Two mouse models of NAFLD were induced by feeding with high fat diet or high fat, choline-deficient, amino acid-defined diet. FIELD STRENGTH/SEQUENCE: 7T/multi-slice multi-echo spin-echo MRE at 400 Hz with motion encoding in the three spatial directions. ASSESSMENT: Hepatic storage and loss moduli were calculated. Histological analysis was based on the NASH Clinical Research Network criteria. STATISTICAL TESTS: Mann-Whitney, Kruskal-Wallis tests, Spearman rank correlations and multiple regressions were used. Diagnostic performance was assessed with areas under the receiver operating characteristic curves (AUCs). P value <0.05 was considered significant. RESULTS: Among the 59 mice with NAFLD, 21 had NASH and 20 had substantial fibrosis (including 8 mice without and 12 mice with NASH). The storage and loss moduli had similar moderate accuracy for diagnosing NASH with AUCs of 0.67 and 0.66, respectively. For diagnosing substantial fibrosis, the AUC of the storage modulus was 0.73 and the AUC of the loss modulus was 0.81, indicating good diagnostic performance. Using Spearman correlations, histological fibrosis, inflammation and steatosis, but not ballooning, were significantly correlated with the visco-elastic parameters. Using multiple regression, fibrosis was the only histological feature independently associated with the visco-elastic parameters. CONCLUSION: MRE in mice with NAFLD suggests that the storage and loss moduli have good diagnostic performance for detecting progressive NAFLD defined as substantial fibrosis rather than NASH. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY STAGE: 2.


Assuntos
Técnicas de Imagem por Elasticidade , Hepatopatia Gordurosa não Alcoólica , Animais , Camundongos , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Estudos Prospectivos , Biópsia , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/etiologia , Fibrose
9.
Rev Neurol (Paris) ; 179(10): 1134-1144, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37827930

RESUMO

Amyotrophic lateral sclerosis (ALS) is a rare disease characterized by a progressive and irreversible degeneration of upper and lower motor neurons leading to death. In France, limited data exist describing the criteria used in clinical practice for diagnosis and follow-up, and how novel therapies may fit in. The objective of this Delphi panel was to obtain an overview of current French practices in ALS diagnosis, management, and follow-up by determining the scales and criteria used in clinical practice outside of clinical trials, as well as the place of a future treatment like AMX0035, acting on endoplasmic reticulum (ER) stress and mitochondrial dysfunction, in the current therapeutic strategies. A questionnaire was administered to 24 ALS healthcare providers practicing in ALS centers in France. Two rounds of remote voting were organized, before proposition of final consensus statements. Consensus was considered reached when at least 66% of the voters agreed. Consensus were obtained to define the new Gold Coast criteria as the ones used in clinical practice to establish the diagnosis of ALS, thus replacing the revised El Escorial criteria, considered too complex and now mainly used to characterize the patient populations to be included in clinical trials. The clinical factors considered to establish ALS diagnosis are mainly the demonstration of progression of the motor deficit and elimination of differential diagnoses. The ALSFRS-R scale is used in daily clinical practice to assess patient's functional impairment in terms of number of points lost, with the bulbar, respiratory, and fine motor subscores being the most important to evaluate independently. A critical medical need was identified regarding the provision of new therapeutic alternatives in ALS. The panel members would support the earliest management of patients. In this landscape, based on data from a very encouraging phase II (Centaur trial), AMX0035 represents a new tool of choice in current treatment strategies for all patients for whom experts are confident in the diagnosis of ALS, in combination with riluzole. These results will need to be confirmed by the ongoing phase III trial (Phoenix trial).


Assuntos
Esclerose Amiotrófica Lateral , Humanos , Esclerose Amiotrófica Lateral/diagnóstico , Esclerose Amiotrófica Lateral/terapia , Riluzol/uso terapêutico , Neurônios Motores , Diagnóstico Diferencial
11.
Rev Neurol (Paris) ; 179(9): 1020-1029, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37735015

RESUMO

Relationships between genes and amyotrophic lateral sclerosis (ALS) have been widely accepted since the first studies highlighting pathogenic mutations in the SOD1 gene 30years ago. Over the last three decades, scientific literature has clearly highlighted the central role played by genetic factors in the disease, in both clinics and pathophysiology, as well as in therapeutics. This implies that health professionals who care for patients with ALS are increasingly faced with patients and relatives eager to have answers to questions related to the role of genetic factors in the occurrence of the disease and the risk for their relatives to develop ALS. In order to address these public health issues, the French ALS network FILSLAN proposed to the Haute Autorité de santé (HAS) the drafting of a French National Protocol (PNDS) on ALS genetics. This PNDS was developed according to the "method for developing a national diagnosis and care protocol for rare diseases" published by the HAS in 2012 (methodological guide for PNDS available on the HAS website: http://www.has-sante.fr/). This document aims to provide the most recent data on the role of genes in ALS and to detail the implications for diagnosis and care.


Assuntos
Esclerose Amiotrófica Lateral , Humanos , Esclerose Amiotrófica Lateral/diagnóstico , Esclerose Amiotrófica Lateral/epidemiologia , Esclerose Amiotrófica Lateral/genética , Mutação
12.
Phys Rev Lett ; 131(4): 041002, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37566836

RESUMO

The LUX-ZEPLIN experiment is a dark matter detector centered on a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility in Lead, South Dakota, USA. This Letter reports results from LUX-ZEPLIN's first search for weakly interacting massive particles (WIMPs) with an exposure of 60 live days using a fiducial mass of 5.5 t. A profile-likelihood ratio analysis shows the data to be consistent with a background-only hypothesis, setting new limits on spin-independent WIMP-nucleon, spin-dependent WIMP-neutron, and spin-dependent WIMP-proton cross sections for WIMP masses above 9 GeV/c^{2}. The most stringent limit is set for spin-independent scattering at 36 GeV/c^{2}, rejecting cross sections above 9.2×10^{-48} cm at the 90% confidence level.

13.
Phys Rev Lett ; 131(2): 021802, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37505961

RESUMO

This Letter reports one of the most precise measurements to date of the antineutrino spectrum from a purely ^{235}U-fueled reactor, made with the final dataset from the PROSPECT-I detector at the High Flux Isotope Reactor. By extracting information from previously unused detector segments, this analysis effectively doubles the statistics of the previous PROSPECT measurement. The reconstructed energy spectrum is unfolded into antineutrino energy and compared with both the Huber-Mueller model and a spectrum from a commercial reactor burning multiple fuel isotopes. A local excess over the model is observed in the 5-7 MeV energy region. Comparison of the PROSPECT results with those from commercial reactors provides new constraints on the origin of this excess, disfavoring at 2.0 and 3.7 standard deviations the hypotheses that antineutrinos from ^{235}U are solely responsible and noncontributors to the excess observed at commercial reactors, respectively.

14.
Sci Rep ; 13(1): 10306, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37365355

RESUMO

Infections caused by multi-drug resistant Enterobacterales (MDR-E) are difficult to treat and cause significant mortality, especially in developing countries. This study characterized the phenotypic and genotypic profiles of 49 randomly selected beta-lactam resistant MDR-E previously isolated from patients being managed in hospitals in Nigeria using whole genome sequencing. The study isolates exhibited 85.5% resistance to 3rd generation cephalosporins and 65.3% resistance to carbapenems. The blaTEM-1B (29, 59.2%), blaCTX-M-15 (38, 77.6%), and blaNDM-1 (17, 51.5%) were the most common penicillinase, ESBL, and carbapenem resistant genes across isolates, respectively. Seventeen (45%) of blaCTX-M-15 was carried on the insertion sequence ISEc9 while blaNDM-1 (11, 64.7%) were associated with ISEc33. None of the 21 plasmids detected were associated with ß-lactamase genes. Higher resistance rates were found in E. coli ST-88 (n = 2) and the high-risk ST-692 (n = 2). For Klebsiella species, the high-risk clones ST-476 (n = 8) and ST-147 (n = 3) predominated and had higher phenotypic resistance rates and higher number of AMR genes. The mechanisms and pattern of antibiotic resistance differ from patterns previously described with isolates harbouring a wide range of AMRGs. The detection of several chromosomally mediated carbapenemases in our study also represents a significant finding that warrants further investigation to better understand its' implications for clinical practice and public health. The selected MDR-Es were found to be pan-susceptible to tigecycline and had very low resistance to fosfomycin, suggesting a potential for these as empiric treatments. A surveillance approach incorporating both conventional laboratory techniques and modern molecular techniques is essential for the comprehensive characterization of the emergence and dissemination of antimicrobial resistance in Enterobacterales infections within Nigeria.


Assuntos
Escherichia coli , beta-Lactamas , Humanos , Antibacterianos/farmacologia , Nigéria/epidemiologia , Testes de Sensibilidade Microbiana , beta-Lactamases/genética , Carbapenêmicos , Resistência beta-Lactâmica/genética , Hospitais
15.
Nat Commun ; 14(1): 2894, 2023 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-37210563

RESUMO

SMARCA4 (BRG1) and SMARCA2 (BRM) are the two paralogous ATPases of the SWI/SNF chromatin remodeling complexes frequently inactivated in cancers. Cells deficient in either ATPase have been shown to depend on the remaining counterpart for survival. Contrary to this paralog synthetic lethality, concomitant loss of SMARCA4/2 occurs in a subset of cancers associated with very poor outcomes. Here, we uncover that SMARCA4/2-loss represses expression of the glucose transporter GLUT1, causing reduced glucose uptake and glycolysis accompanied with increased dependency on oxidative phosphorylation (OXPHOS); adapting to this, these SMARCA4/2-deficient cells rely on elevated SLC38A2, an amino acid transporter, to increase glutamine import for fueling OXPHOS. Consequently, SMARCA4/2-deficient cells and tumors are highly sensitive to inhibitors targeting OXPHOS or glutamine metabolism. Furthermore, supplementation of alanine, also imported by SLC38A2, restricts glutamine uptake through competition and selectively induces death in SMARCA4/2-deficient cancer cells. At a clinically relevant dose, alanine supplementation synergizes with OXPHOS inhibition or conventional chemotherapy eliciting marked antitumor activity in patient-derived xenografts. Our findings reveal multiple druggable vulnerabilities of SMARCA4/2-loss exploiting a GLUT1/SLC38A2-mediated metabolic shift. Particularly, unlike dietary deprivation approaches, alanine supplementation can be readily applied to current regimens for better treatment of these aggressive cancers.


Assuntos
Glutamina , Neoplasias , Humanos , Transportador de Glucose Tipo 1 , Adenosina Trifosfatases/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Suplementos Nutricionais , DNA Helicases/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
16.
Mayo Clin Proc ; 98(4): 549-558, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37019514

RESUMO

OBJECTIVE: To evaluate the value of serial C-reactive protein (CRP) measurements in predicting the risk of cardiovascular disease (CVD), cancer, and mortality. METHODS: The analysis was performed using data from two prospective, population-based observational cohorts: the Prevention of Renal and Vascular End-Stage Disease (PREVEND) study and the Framingham Heart Study (FHS). A total of 9253 participants had CRP measurements available at two examinations (PREVEND: 1997-1998 and 2001-2002; FHS Offspring cohort: 1995-1998 and 1998-2001). All CRP measurements were natural log-transformed before analyses. Cardiovascular disease included fatal and nonfatal cardiovascular, cerebrovascular and peripheral vascular events, and heart failure. Cancer included all malignancies except nonmelanoma skin cancers. RESULTS: The mean age of the study population at baseline was 52.4±12.1 years and 51.2% (n=4733) were women. Advanced age, female sex, smoking, body mass index, and total cholesterol were associated with greater increases in CRP levels over time (Pall<.001 in the multivariable model). Baseline CRP, as well as increase in CRP over time (ΔCRP), were associated with incident CVD (hazard ratio [HR]: 1.29 per 1-SD increase; 95% confidence interval [CI]: 1.29 to 1.47, and HR per 1-SD increase: 1.19; 95% CI: 1.09 to 1.29 respectively). Similar findings were observed for incident cancer (baseline CRP, HR: 1.17; 95% CI: 1.09 to 1.26; ΔCRP, HR: 1.08; 95% CI: 1.01 to 1.15) and mortality (baseline CRP, HR: 1.29; 95% CI: 1.21 to 1.37; ΔCRP, HR: 1.10; 95% CI: 1.05 to 1.16). CONCLUSION: Initial as well as subsequent increases in CRP levels predict future CVD, cancer, and mortality in the general population.


Assuntos
Doenças Cardiovasculares , Neoplasias , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Masculino , Proteína C-Reativa/análise , Doenças Cardiovasculares/epidemiologia , Fatores de Risco , Estudos Prospectivos
17.
J Cancer Res Clin Oncol ; 149(10): 7717-7728, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37004598

RESUMO

AIM: To summarise our centre's experience managing patients with neuroendocrine tumours (NETs) in the first 5 years after the introduction of peptide receptor radionuclide therapy (PRRT) with [177Lu]Lu-DOTA-octreotate (LUTATE). The report emphasises aspects of the patient management related to functional imaging and use of radionuclide therapy. METHODS: We describe the criteria for treatment with LUTATE at our centre, the methodology for patient selection, and the results of an audit of clinical measures, imaging results and patient-reported outcomes. Subjects are treated initially with four cycles of ~ 8 GBq of LUTATE administered as an outpatient every 8 weeks. RESULTS: In the first 5 years offering LUTATE, we treated 143 individuals with a variety of NETs of which approx. 70% were gastroentero-pancreatic in origin (small bowel: 42%, pancreas: 28%). Males and females were equally represented. Mean age at first treatment with LUTATE was 61 ± 13 years with range 28-87 years. The radiation dose to the organs considered most at risk, the kidneys, averaged 10.6 ± 4.0 Gy in total. Median overall survival (OS) from first receiving LUTATE was 72.5 months with a median progression-free survival (PFS) of 32.3 months. No evidence of renal toxicity was seen. The major long-term complication seen was myelodysplastic syndrome (MDS) with a 5% incidence. CONCLUSIONS: LUTATE treatment for NETs is a safe and effective treatment. Our approach relies heavily on functional and morphological imaging informing the multidisciplinary team of NET specialists to guide appropriate therapy, which we suggest has contributed to the favourable outcomes seen.


Assuntos
Tumores Neuroendócrinos , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Tumores Neuroendócrinos/patologia , Medicina de Precisão , Octreotida/uso terapêutico , Imagem Molecular , Receptores de Peptídeos , Radioisótopos
18.
Nanomedicine (Lond) ; 18(1): 53-66, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36938861

RESUMO

Background: Implantation of insulin-secreting cells has been trialed as a treatment for Type 1 diabetes mellitus; however, the host immunogenic response limits their effectiveness. Methodology: The authors developed a core-shell nanostructure of upconversion nanoparticle-mesoporous silica for controlled local delivery of an immunomodulatory agent, MCC950, using near-infrared light and validated it in in vitro models of fibrosis. Results: The individual components of the nanosystem did not affect the proliferation of insulin-secreting cells, unlike fibroblast proliferation (p < 0.01). The nanosystem is effective at releasing MCC950 and preventing fibroblast differentiation (p < 0.01), inflammation (IL-6 expression; p < 0.05) and monocyte adhesion (p < 0.01). Conclusion: This MCC950-loaded nanomedicine system could be used in the future together with insulin-secreting cell implants to increase their longevity as a curative treatment for Type 1 diabetes mellitus.


This work describes a new drug-delivery system that can release an immunomodulatory drug in a controlled manner and prevent fibrosis, which is part of the immune response when a foreign body is implanted. This system can be particularly useful for insulin-secreting cell implants, used to replace multiple daily injections of insulin and improve the quality of life of people with Type 1 diabetes mellitus. By preventing the immune response that leads to fibrosis, the longevity of these cellular implants can be extended without the need for frequent replacement procedures. This innovative nanosystem can release the required amount of immunomodulatory drug, which could be stimulated with the use of special light, hence showing the ability for local and extended delivery. This type of system has the potential to reduce the side effects associated with oral daily administration of immunomodulatory agents in people with Type 1 diabetes mellitus.


Assuntos
Diabetes Mellitus Tipo 1 , Nanopartículas , Nanoestruturas , Humanos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Nanoestruturas/química
19.
Rev Sci Instrum ; 94(1): 015112, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36725581

RESUMO

Maintaining the electric fields necessary for the current generation of noble liquid time projection chambers (TPCs), with drift lengths exceeding 1 m, requires a large negative voltage applied to their cathode. Delivering such high voltage is associated with an elevated risk of electrostatic discharge and electroluminescence, which would be detrimental to the performance of the experiment. The Xenon Breakdown Apparatus (XeBrA) is a 5-l, high voltage test chamber built to investigate the contributing factors to electrical breakdown in noble liquids. In this work, we present the main findings after conducting scans over stressed electrode areas, surface finish, pressure, and high voltage ramp speed in the medium of liquid xenon. Area scaling and surface finish were observed to be the dominant factors affecting breakdown, whereas no significant changes were observed with varying pressure or ramp speed. A general rise in both the anode current and photon rate was observed in the last 30 s, leading up to a breakdown, with a marked increase in the last couple of seconds. In addition, the position of breakdowns was reconstructed with a system of high-speed cameras and a moderate correlation with the Fowler-Nordheim field emission model was found. Tentative evidence for bubble nucleation being the originating mechanism of breakdown in the liquid was also observed. We deem the results presented in this work to be of particular interest for the design of future, large TPCs, and practical recommendations are provided.

20.
Am J Pathol ; 193(4): 456-473, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36657718

RESUMO

Poorly differentiated (PD) chordoma, a rare, aggressive tumor originating from notochordal tissue, shows loss of SMARCB1 expression, a core component of the Switch/Sucrose Non-Fermentable (SWI/SNF) chromatin remodeling complexes. To determine the impact of SMARCB1 re-expression on cell growth and gene expression, two SMARCB1-negative PD chordoma cell lines with an inducible SMARCB1 expression system were generated. After 72 hours of induction of SMARCB1, both SMARCB1-negative PD chordoma cell lines continued to proliferate. This result contrasted with those observed with SMARCB1-negative rhabdoid cell lines in which SMARCB1 re-expression caused the rapid inhibition of growth. We found that the lack of growth inhibition may arise from the loss of CDKN2A (p16INK4A) expression in PD chordoma cell lines. RNA-sequencing of cell lines after SMARCB1 re-expression showed a down-regulation for rRNA and RNA processing as well as metabolic processing and increased expression of genes involved in cell adhesion, cell migration, and development. Taken together, these data establish that SMARCB1 re-expression in PD chordomas alters the repertoire of SWI/SNF complexes, perhaps restoring those associated with cellular differentiation. These novel findings support a model in which SMARCB1 inactivation blocks the conversion of growth-promoting SWI/SNF complexes to differentiation-inducing ones, and they implicate SMARCB1 loss as a late event in tumorigenic progression. Importantly, the absence of growth inhibition after SMARCB1 restoration creates a unique opportunity to identify therapeutic vulnerabilities.


Assuntos
Cordoma , Humanos , Cordoma/genética , Cordoma/patologia , Fatores de Transcrição/metabolismo , Diferenciação Celular/genética , Carcinogênese , Proteína SMARCB1/genética
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