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Faict S, Oudaert I, D’Auria L, Dehairs J, Maes K, Vlummens P, De Veirman K, De Bruyne E, Fostier K, Vande Broek I, Schots R, Vanderkerken K, Swinnen JV, Menu E. The Transfer of Sphingomyelinase Contributes to Drug Resistance in Multiple Myeloma. Cancers (Basel) 2019; 11:cancers11121823. [PMID: 31756922 PMCID: PMC6966559 DOI: 10.3390/cancers11121823] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 11/12/2019] [Accepted: 11/18/2019] [Indexed: 02/07/2023] Open
Abstract
Multiple myeloma (MM) is well-known for the development of drug resistance, leading to relapse. Therefore, finding novel treatment strategies remains necessary. By performing a lipidomics assay on MM patient plasma, we aimed to identify new targets. We observed a dysregulation in the sphingolipid metabolism, with the upregulation of several ceramides and downregulation of sphingomyelin. This imbalance suggests an increase in sphingomyelinase, the enzyme responsible for hydrolyzing sphingomyelin into ceramide. We confirmed the upregulation of acid sphingomyelinase (ASM) in primary MM cells. Furthermore, we observed an increase in ASM expression in MM cell lines treated with melphalan or bortezomib, as well as in their exosomes. Exosomes high in ASM content were able to transfer the drug-resistant phenotype to chemosensitive cells, hereby suggesting a tumor-protective role for ASM. Finally, inhibition of ASM by amitriptyline improved drug sensitivity in MM cell lines and primary MM cells. In summary, this study is the first to analyze differences in plasma lipid composition of MM patients and match the observed differences to an upregulation of ASM. Moreover, we demonstrate that amitriptyline is able to inhibit ASM and increase sensitivity to anti-myeloma drugs. This study, therefore, provides a rational to include ASM-targeting-drugs in combination strategies in myeloma patients.
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Journal Article |
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Wollast R, Schmitz M, Bigot A, Luminet O. The Theory of Planned Behavior during the COVID-19 pandemic: A comparison of health behaviors between Belgian and French residents. PLoS One 2021; 16:e0258320. [PMID: 34735473 PMCID: PMC8568184 DOI: 10.1371/journal.pone.0258320] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 09/23/2021] [Indexed: 11/19/2022] Open
Abstract
The COVID-19 pandemic presents a global crisis and authorities have encouraged the population to promote preventive health behaviors to slow the spread of the virus. While the literature on psychological factors influencing health behaviors during the COVID-19 is flourishing, there is a lack of cross-national research focusing on multiple health behaviors. The present study overcomes this limitation and affords a validation of the Theory of Planned Behavior (TPB) as a conceptual framework for explaining the adoption of handwashing and limitation of social contacts, two health behaviors that highly differ in their nature. Specifically, we compare TPB model on these two protective behaviors among people living in Belgium (N = 3744) and France (N = 1060) during the COVID-19 sanitary crisis. Data were collected from March 18 until April 19, 2020, which corresponds to the spring lockdown and the first peak of the pandemic in these countries. Results indicated that more positive attitudes, greater social norms, increased perceived control and higher intentions were related to higher adherence to handwashing and limitation of social contacts, for both Belgian and French residents. Ultimately, we argued that the TPB model tends to manifest similarly across countries in explaining health behaviors, when comparing handwashing and limitation of social contacts among individuals living in different national contexts.
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Comparative Study |
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Abstract
PURPOSE OF REVIEW Numerous clinically relevant allergenic molecules enhance the performance of specific (s) IgE tests and improve the specificity of allergy diagnosis. This review aimed to summarize our current knowledge of the high-molecular-weight allergens involved in the development of occupational asthma and rhinitis and to critically analyze the contribution of component-resolved diagnosis in the management of these conditions. RECENT FINDINGS There is a lack of standardization and validation for most available extracts of occupational agents, and assessment of sIgE reactivity to occupational allergen components has been poorly investigated, with the notable exception of natural rubber latex (NRL) and wheat flour. In the case of NRL, the application of recombinant single allergens and amplification of natural extracts with stable recombinant allergens improved the test sensitivity. IgE-sensitization profile in patients with baker's asthma showed great interindividual variation, and extract-based diagnostic is still recommended. For other occupational allergens, it remains necessary to evaluate the relevance of single allergen molecules for the sensitization induced by occupational exposure. Progress has been made to characterize occupational allergens especially NRL and wheat, although there is still an unmet need to increase the knowledge of occupational allergens, to include standardized tools into routine diagnostic, and to evaluate their usefulness in clinical practice.
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Vilela JDMV, Moghassemi S, Dadashzadeh A, Dolmans MM, Azevedo RB, Amorim CA. Safety of Lavender Oil-Loaded Niosomes for In Vitro Culture and Biomedical Applications. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:1999. [PMID: 35745338 PMCID: PMC9229298 DOI: 10.3390/nano12121999] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 05/30/2022] [Accepted: 06/09/2022] [Indexed: 12/22/2022]
Abstract
(1) Background: Essential oils have long been used as therapeutic agents. Lavender (Lavandula angustifolia) oil (LO) is an antispasmodic, anticonvulsant, relaxant, painkilling, and antimicrobial essential oil investigated as a natural substance for biomedical therapies. Nanoparticles have shown significant promise in improving drug delivery and efficacy. Considering these benefits, the aim of this study was to evaluate the toxicity of LO and lavender oil niosomes (LONs) in stem cells and myofibroblast models cultured in vitro. (2) Methods: Adipose tissue-derived stem cells and myometrial cells were cultured with LO or LONs at different concentrations (0, 0.016%, 0.031%, and 0.063%) and toxicity was evaluated with PrestoBlue™ and live/dead assay using calcein and ethidium homodimer. (3) Results: Cell viability was similar to controls in all groups, except in 0.063% LO for myometrial cells, which showed lower viability than the control medium. (4) Conclusion: These results suggest that both LO and LONs are safe for cell culture and may be used for pharmaceutical and biomedical therapies in future applications in regenerative medicine.
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Turusheva A, Frolova E, Korystina E, Zelenukha D, Tadjibaev P, Gurina N, Turkeshi E, Degryse JM. Do commonly used frailty models predict mortality, loss of autonomy and mental decline in older adults in northwestern Russia? A prospective cohort study. BMC Geriatr 2016; 16:98. [PMID: 27160275 PMCID: PMC4862060 DOI: 10.1186/s12877-016-0276-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2015] [Accepted: 05/05/2016] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Frailty prevalence differs across countries depending on the models used to assess it that are based on various conceptual and operational definitions. This study aims to assess the clinical validity of three frailty models among community-dwelling older adults in north-western Russia where there is a higher incidence of cardiovascular disease and lower life expectancy than in European countries. METHODS The Crystal study is a population-based prospective cohort study in Kolpino, St. Petersburg, Russia. A random sample of the population living in the district was stratified into two age groups: 65-75 (n = 305) and 75+ (n = 306) and had a baseline comprehensive health assessment followed by a second one after 33.4 +/-3 months. The total observation time was 47 +/-14.6 months. Frailty was assessed according to the models of Fried, Puts and Steverink-Slaets. Its association with mortality at 5 years follow-up as well as dependency, mental and physical decline at around 2.5 years follow up was explored by multivariable and time-to-event analyses. RESULTS Mortality was predicted independently from age, sex and comorbidities only by the frail status of the Fried model in those over 75 years old [HR (95 % CI) = 2.50 (1.20-5.20)]. Mental decline was independently predicted only by pre-frail [OR (95 % CI) = 0.24 (0.10-0.55)] and frail [OR (95 % CI) = 0.196 (0.06-0.67)] status of Fried model in those 65-75 years old. The prediction of dependency and physical decline by pre-frail and frail status of any the three frailty models was not statistically significant in this cohort of older adults. CONCLUSIONS None of the three frailty models was valid at predicting 5 years mortality and disability, mental and physical decline at 2.5 years in a cohort of older adults in north-west Russia. Frailty by the Fried model had only limited value for mortality in those 75 years old and mental decline in those 65-75 years old. Further research is needed to identify valid frailty markers for older adults in this population.
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Observational Study |
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Kaljević J, Tesseur C, Le TBK, Laloux G. Cell cycle-dependent organization of a bacterial centromere through multi-layered regulation of the ParABS system. PLoS Genet 2023; 19:e1010951. [PMID: 37733798 PMCID: PMC10547168 DOI: 10.1371/journal.pgen.1010951] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 10/03/2023] [Accepted: 09/01/2023] [Indexed: 09/23/2023] Open
Abstract
The accurate distribution of genetic material is crucial for all organisms. In most bacteria, chromosome segregation is achieved by the ParABS system, in which the ParB-bound parS sequence is actively partitioned by ParA. While this system is highly conserved, its adaptation in organisms with unique lifestyles and its regulation between developmental stages remain largely unexplored. Bdellovibrio bacteriovorus is a predatory bacterium proliferating through polyploid replication and non-binary division inside other bacteria. Our study reveals the subcellular dynamics and multi-layered regulation of the ParABS system, coupled to the cell cycle of B. bacteriovorus. We found that ParA:ParB ratios fluctuate between predation stages, their balance being critical for cell cycle progression. Moreover, the parS chromosomal context in non-replicative cells, combined with ParB depletion at cell division, critically contribute to the unique cell cycle-dependent organization of the centromere in this bacterium, highlighting new levels of complexity in chromosome segregation and cell cycle control.
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Santos-Ribeiro D, Lecocq M, de Beukelaer M, Verleden S, Bouzin C, Ambroise J, Dorfmuller P, Yakoub Y, Huaux F, Quarck R, Karmouty-Quintana H, Ghigna MR, Bignard J, Nadaud S, Soubrier F, Horman S, Perros F, Godinas L, Pilette C. Disruption of GCN2 Pathway Aggravates Vascular and Parenchymal Remodeling during Pulmonary Fibrosis. Am J Respir Cell Mol Biol 2023; 68:326-338. [PMID: 36476191 PMCID: PMC12042145 DOI: 10.1165/rcmb.2021-0541oc] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 12/06/2022] [Indexed: 12/12/2022] Open
Abstract
Pulmonary fibrosis (PF) and pulmonary hypertension (PH) are chronic diseases of the pulmonary parenchyma and circulation, respectively, which may coexist, but underlying mechanisms remain elusive. Mutations in the GCN2 (general control nonderepressible 2) gene (EIF2AK4 [eukaryotic translation initiation factor 2 alpha kinase 4]) were recently associated with pulmonary veno-occlusive disease. The aim of this study is to explore the involvement of the GCN2/eIF2α (eukaryotic initiation factor 2α) pathway in the development of PH during PF, in both human disease and in a laboratory animal model. Lung tissue from patients with PF with or without PH was collected at the time of lung transplantation, and control tissue was obtained from tumor resection surgery. Experimental lung disease was induced in either male wild-type or EIF2AK4-mutated Sprague-Dawley rats, randomly receiving a single intratracheal instillation of bleomycin or saline. Hemodynamic studies and organ collection were performed 3 weeks after instillation. Only significant results (P < 0.05) are presented. In PF lung tissue, GCN2 protein expression was decreased compared with control tissue. GCN2 expression was reduced in CD31+ endothelial cells. In line with human data, GCN2 protein expression was decreased in the lung of bleomycin rats compared with saline. EIF2AK4-mutated rats treated with bleomycin showed increased parenchymal fibrosis (hydroxyproline concentrations) and vascular remodeling (media wall thickness) as well as increased right ventricular systolic pressure compared with wild-type animals. Our data show that GCN2 is dysregulated in both humans and in an animal model of combined PF and PH. The possibility of a causative implication of GCN2 dysregulation in PF and/or PH development should be further studied.
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Vaes B, Indestege P, Serneels T, Hegendörfer E, van Peet PG, Poortvliet RKE, Wallemacq P, Gussekloo J, Degryse J. Biomarkers versus traditional risk factors to predict cardiovascular events in very old adults: cross-validated prospective cohort study. BMJ Open 2020; 10:e035809. [PMID: 32595156 PMCID: PMC7322328 DOI: 10.1136/bmjopen-2019-035809] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
OBJECTIVES To test new cardiovascular (CV) risk models in very old adults with and without a history of CV disease (CVD), based on traditional risk factors and biomarkers. DESIGN Cross-validated prospective cohort study. The models were tested in the BELFRAIL Study and externally validated in the Leiden 85-plus Study. SETTING General practice, Belgium and The Netherlands. PARTICIPANTS The BELFRAIL cohort consisted of 266 patients aged 80 years or older without a history of CVD and 260 with a history of CVD. The Leiden 85-plus Study consisted of 264 patients aged 85 years without a history of CVD and 282 with a history of CVD. OUTCOME MEASURES The model with traditional risk factors and biomarkers, as well as the model using only biomarkers, was compared with the model with only traditional risk factors to predict 3-year CV morbidity and mortality. A competing-risk analysis was performed, and the continuous net reclassification improvement (NRI), integrated discrimination improvement (IDI) and net benefit were used to compare the predictive value of the different models. RESULTS Traditional risk factors poorly predicted CV mortality and morbidity. In participants without a history of CVD, adding N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) improved the prediction (NRI 0.56 (95% CI 0.16 to 0.99) and relative IDI 4.01 (95% CI 2.19 to 6.28)). In participants with a history of CVD, the NRI with the addition of NT-pro-BNP and high-sensitivity C reactive protein was 0.38 (95% CI 0.09 to 0.70), and the relative IDI was 0.53 (95% CI 0.23 to 0.90). Moreover, in participants without a history of CVD, NT-pro-BNP performed well as a stand-alone predictor (NRI 0.32 (95% CI -0.12 to 0.74) and relative IDI 3.44 (95% CI 1.56 to 6.09)). CONCLUSIONS This study tested new risk models to predict CV morbidity and mortality in very old adults. Especially, NT-pro-BNP showed a strong added predictive value. This opens perspectives for clinicians who are in need of an easily applicable strategy for CV risk prediction in very old adults.
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Boyer E, Deltenre L, Dourte M, Colmant L, Paître E, Sleegers K, Suelves N, Hanseeuw B, Kienlen-Campard P. Comparison of plasma soluble and extracellular vesicles-associated biomarkers in Alzheimer's disease patients and cognitively normal individuals. Alzheimers Res Ther 2024; 16:141. [PMID: 38943196 PMCID: PMC11212434 DOI: 10.1186/s13195-024-01508-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Accepted: 06/19/2024] [Indexed: 07/01/2024]
Abstract
BACKGROUND Amyloid-β (Aβ) and tau are brain hallmarks of Alzheimer's disease (AD), also present in blood as soluble biomarkers or encapsulated in extracellular vesicles (EVs). Our goal was to assess how soluble plasma biomarkers of AD pathology correlate with the number and content of EVs. METHODS Single-molecule enzyme-linked assays were used to quantify Aβ42/40 and tau in plasma samples and neurally-derived EVs (NDEVs) from a cohort of APOE ε4- (n = 168) and APOE ε4+ (n = 68) cognitively normal individuals and AD patients (n = 55). The ratio of CD56 (Neuronal cell-adhesion molecule) to CD81 signal measured by ELISA-DELFIA was used for the relative quantification of NDEVs in plasma samples. RESULTS The soluble plasma Aβ42/40 ratio is decreased in AD patients compared to cognitively normal individuals. The amount and content (Aβ40, Aβ42, tau) of plasma NDEVs were similar between groups. Plasma NDEVs quantity remain consistent with aging and between AD and CN individuals. However, the quantity of soluble biomarkers was negatively correlated to NDEVs number in cognitively normal individuals, while in AD patients, this correlation is lost, suggesting a shift in the mechanism underpinning the production and the release of these biomarkers in pathological conditions. CONCLUSION Soluble plasma Aβ42/40 ratio is the most robust biomarker to discriminate between AD patients and CN individuals, as it normalizes for the number of NDEVs. Analysis of NDEVs and their content pointed toward peculiar mechanisms of Aβ release in AD. Further research on independent cohorts can confirm our findings and assess whether plasma Aβ and tau need correction by NDEVs for better AD risk identification in CN populations.
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Comparative Study |
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Wollast R, Schmitz M, Bigot A, Brisbois M, Luminet O. Predicting health behaviors during the COVID-19 pandemic: A longitudinal study. PLoS One 2024; 19:e0299868. [PMID: 38489308 PMCID: PMC10942062 DOI: 10.1371/journal.pone.0299868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 02/16/2024] [Indexed: 03/17/2024] Open
Abstract
We investigated the social, emotional, and cognitive predictors of adherence to four health behaviors (handwashing, mask wearing, social contact limitations, and physical distancing) during one critical phase of the COVID-19 pandemic. We collected data (N = 5803, mean age = 53; 57% women) in Belgium at five time points between April and July 2021, a time during which infections evolved from high (third wave of the pandemic) to low numbers of COVID-19 cases. The results show that the social, emotional, and cognitive predictors achieved high levels of explained variance (R2 > .60). In particular, the central components of behavioral change (attitudes, intentions, control, habits, norms, and risk) were the strongest and most consistent predictors of health behaviors over time. Likewise, autonomous motivation and empathetic emotions (e.g., attentive, compassionate) had a positive impact on health behavior adherence, whereas it was the opposite for lively emotions (e.g., active, enthusiastic). These results offer policymakers actionable insights into the most potent and stable factors associated with health behaviors, equipping them with effective strategies to curtail the spread of future infectious diseases.
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Grubliauskaitė M, Vlieghe H, Moghassemi S, Dadashzadeh A, Camboni A, Gudlevičienė Ž, Amorim CA. Influence of ovarian stromal cells on human ovarian follicle growth in a 3D environment. Hum Reprod Open 2023; 2024:hoad052. [PMID: 38204939 PMCID: PMC10776356 DOI: 10.1093/hropen/hoad052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 11/30/2023] [Indexed: 01/12/2024] Open
Abstract
STUDY QUESTION Do ovarian stromal cells (OSCs) influence the viability and growth of human preantral follicles in vitro? SUMMARY ANSWER A feeder layer of OSCs promotes the growth and transition of low developmental stage follicles to the primary/secondary stage while maintaining a high proportion of viable follicles. WHAT IS KNOWN ALREADY In the ovary, follicles rely on the support of ovarian cells, which secrete essential factors for their survival and development. This phenomenon has also been demonstrated in vitro through the 3D culture of isolated mouse primary and secondary follicles on a feeder layer of OSCs. This co-culture notably enhances follicle survival and growth. STUDY DESIGN SIZE DURATION Pre-antral follicles were isolated from human frozen-thawed ovarian tissue biopsies and then encapsulated in 1% alginate scaffolds. These embedded preantral follicles were either placed directly on the OSCs feeder layer or at the bottom of a culture dish for a 7-day in vitro culture (control). The study compared follicle viability, growth, and hormone production between the different groups. PARTICIPANTS/MATERIALS SETTING METHODS Primordial/intermediate and primary follicles were isolated from frozen-thawed ovarian tissue of cancer patients (n = 6). OSCs were then isolated from ovarian tissue of post-menopausal women and cultured as a feeder layer. Follicle diameter was measured on Days 0 and 7 using an inverted microscope to assess their development based on the increase in diameter. Viability was evaluated by staining a subset of follicles (n = 87) with calcein AM and ethidium homodimer-I, followed by classification into healthy/minimally damaged and damaged/dead follicles using confocal fluorescence microscopy. Additionally, estradiol levels were measured using ELISA. MAIN RESULTS AND THE ROLE OF CHANCE A total of 382 human preantral follicles (370 primordial/intermediate and 12 primary) with a mean diameter of 40.8 ± 9.9 µm (mean ± SD) were isolated, embedded in 1% alginate hydrogel, and placed either on a monolayer of OSCs or directly on the plastic. By Day 7, the preantral follicles showed a significant size increase under both culture conditions (P < 0.0001 for D0 vs D7). The mean diameter of follicles (quiescent and growing) cultured on the feeder layer was 80.6 ± 11.0 μm compared to 67.3 ± 7.2 μm without it (P = 0.07). During the 7-day in vitro culture, the viability of the follicles significantly decreased only in the group without an OSCs monolayer compared to the D0 viability (P < 0.05). Additionally, more follicles transitioned to a higher developmental stage in the presence of OSCs (D0 primordial/intermediate: 184, primary: 7 vs D7 primordial/intermediate: 51, primary/secondary: 93) compared to those cultured without OSCs (D0 primordial/intermediate: 186, primary: 5 vs D7 primordial/intermediate: 84, primary/secondary: 65; P < 0.001). Specifically, 66 and 44 follicles reached the secondary stage (75< x <200 μm) in the presence and absence of OSCs, respectively. Moreover, the estradiol level was significantly higher (P = 0.006) in the alginate beads containing primordial and growing follicles cultured on the OSCs (54.1 ± 14.2 pg/ml) compared to those cultured without OSCs (29.9 ± 4.0 pg/ml). LARGE SCALE DATA N/A. LIMITATIONS REASONS FOR CAUTION This study was conducted using a short-term culture, and none of the primordial/intermediate/primary follicles reached the antral stage. Further in vitro studies are required to investigate follicular developmental capacity, physiology, and steroidogenesis in alginate scaffolds with human OSCs. WIDER IMPLICATIONS OF THE FINDINGS Activating and growing human primordial/intermediate follicles to a secondary stage in in vitro short-term culture has posed a longstanding challenge. However, co-culturing with human OSCs has shown the potential to overcome this limitation. STUDY FUNDING/COMPETING INTERESTS This study was supported by grants from the Fonds National de la Recherche Scientifique de Belgique (FNRS-PDR Convention grant number T.0004.20 awarded to C.A.A., PhD scholarship awarded to H.V.), Fondation Louvain (awarded to C.A.A.; PhD scholarship awarded to S.M., as part of a legacy from Mr Frans Heyes, and PhD scholarship awarded to A.D. as part of a legacy from Mrs Ilse Schirmer), Foundation Against Cancer (grant 2018-042 awarded to A.C.), and the European Community Structural Funds and Lithuanian Research Council (Agreement registration No. D-19-0874). The authors have no conflicts of interest to declare.
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Glibert H, Bridoux L, Palate M, Piget C, Ahn MT, Gualdani R, Domínguez-Bajo A, Clotman F, Rijli FM, Gofflot F. Primary Cell Cultures in Neurobiology: Optimized Protocol for Culture of Mouse Fetal Hindbrain Neurons. Cells 2025; 14:758. [PMID: 40497933 PMCID: PMC12153581 DOI: 10.3390/cells14110758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2025] [Revised: 05/19/2025] [Accepted: 05/20/2025] [Indexed: 06/19/2025] Open
Abstract
Primary cultures of neural cells are important key tools for basic and translational neuroscience research. These primary cell cultures are classically generated from the rodent brain hippocampus or cortex and optimized for enrichment in neurons at the expense of glial cells. Importantly, considerable differences exist in neuronal cell populations and in glial cell contribution between different brain regions. Because many basic and translational research projects aim to identify mechanisms underlying brainstem neuronal networks that affect major vital functions, primary cultures representative of cell populations present in the hindbrain are required. However, the preparation of primary cultures of brainstem/hindbrain neurons is scarcely described in the literature, limiting the possibilities for studying the development and physiology of these brain regions in vitro. The present report describes a reliable protocol to dissociate and culture in vitro embryonic mouse fetal hindbrain neurons in a defined culture medium, while control of astrocytes' expansion was attained by using a chemically defined, serum-free supplement, namely CultureOne™. The neuronal cells maintained according to this protocol differentiate and, by 10 days in vitro, they develop extensive axonal and dendritic branching. Using immunofluorescence, we further characterized the different cell populations and neuronal subtypes. Patch-clamp recordings demonstrate the excitable nature of these neurons, while colocalization of pre- and postsynaptic neuronal markers showed that neurons form mature synapses, suggesting the establishment of functional networks in vitro. The cultures produced by this method show excellent reproducibility and can be used for molecular, biochemical, and physiological analyses, as illustrated here for tamoxifen-induced Cre recombination in genetically-modified neural cells.
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Fain JS, Wangermez C, Loriot A, Denoue C, De Smet C. DNA Hypomethylation Underlies Epigenetic Swapping between AGO1 and AGO1-V2 Isoforms in Tumors. EPIGENOMES 2024; 8:24. [PMID: 39051182 PMCID: PMC11270204 DOI: 10.3390/epigenomes8030024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Revised: 06/10/2024] [Accepted: 06/18/2024] [Indexed: 07/27/2024] Open
Abstract
Human tumors progress in part by accumulating epigenetic alterations, which include gains and losses of DNA methylation in different parts of the cancer cell genome. Recent work has revealed a link between these two opposite alterations by showing that DNA hypomethylation in tumors can induce the expression of transcripts that overlap downstream gene promoters and thereby induce their hypermethylation. Preliminary in silico evidence prompted us to investigate if this mechanism applies to the locus harboring AGO1, a gene that plays a central role in miRNA biogenesis and RNA interference. Inspection of public RNA-Seq datasets and RT-qPCR experiments show that an alternative transcript starting 13.4 kb upstream of AGO1 (AGO1-V2) is expressed specifically in testicular germ cells, and becomes aberrantly activated in different types of tumors, particularly in tumors of the esophagus, stomach, and lung. This expression pattern classifies AGO1-V2 into the group of "Cancer-Germline" (CG) genes. Analysis of transcriptomic and methylomic datasets provided evidence that transcriptional activation of AGO1-V2 depends on DNA demethylation of its promoter region. Western blot experiments revealed that AGO1-V2 encodes a shortened isoform of AGO1, corresponding to a truncation of 75 aa in the N-terminal domain, and which we therefore referred to as "∆NAGO1". Interestingly, significant correlations between hypomethylation/activation of AGO1-V2 and hypermethylation/repression of AGO1 were observed upon examination of tumor cell lines and tissue datasets. Overall, our study reveals the existence of a process of interdependent epigenetic alterations in the AGO1 locus, which promotes swapping between two AGO1 protein-coding mRNA isoforms in tumors.
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Ray A, Minh Tran TT, Santos Natividade RD, Moreira RA, Simpson JD, Mohammed D, Koehler M, L Petitjean SJ, Zhang Q, Bureau F, Gillet L, Poma AB, Alsteens D. Single-Molecule Investigation of the Binding Interface Stability of SARS-CoV-2 Variants with ACE2. ACS NANOSCIENCE AU 2024; 4:136-145. [PMID: 38644967 PMCID: PMC11027127 DOI: 10.1021/acsnanoscienceau.3c00060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 02/20/2024] [Accepted: 02/21/2024] [Indexed: 04/23/2024]
Abstract
The SARS-CoV-2 pandemic spurred numerous research endeavors to comprehend the virus and mitigate its global severity. Understanding the binding interface between the virus and human receptors is pivotal to these efforts and paramount to curbing infection and transmission. Here we employ atomic force microscopy and steered molecular dynamics simulation to explore SARS-CoV-2 receptor binding domain (RBD) variants and angiotensin-converting enzyme 2 (ACE2), examining the impact of mutations at key residues upon binding affinity. Our results show that the Omicron and Delta variants possess strengthened binding affinity in comparison to the Mu variant. Further, using sera from individuals either vaccinated or with acquired immunity following Delta strain infection, we assess the impact of immunity upon variant RBD/ACE2 complex formation. Single-molecule force spectroscopy analysis suggests that vaccination before infection may provide stronger protection across variants. These results underscore the need to monitor antigenic changes in order to continue developing innovative and effective SARS-CoV-2 abrogation strategies.
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Drążyk D, Missal M. The oculomotor signature of expected surprise. Sci Rep 2022; 12:2543. [PMID: 35169177 PMCID: PMC8847614 DOI: 10.1038/s41598-022-06403-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 01/31/2022] [Indexed: 11/09/2022] Open
Abstract
Expected surprise, defined as the anticipation of uncertainty associated with the occurrence of a future event, plays a major role in gaze shifting and spatial attention. In the present study, we analyzed its impact on oculomotor behavior. We hypothesized that the occurrence of anticipatory saccades could decrease with increasing expected surprise and that its influence on visually-guided responses could be different given the presence of sensory information and perhaps competitive attentional effects. This hypothesis was tested in humans using a saccadic reaction time task in which a cue indicated the future stimulus position. In the 'no expected surprise' condition, the visual target could appear only at one previously cued location. In other conditions, more likely future positions were cued with increasing expected surprise. Anticipation was more frequent and pupil size was larger in the 'no expected surprise' condition compared with all other conditions, probably due to increased arousal. The latency of visually-guided saccades increased linearly with the logarithm of surprise (following Hick's law) but their maximum velocity repeated the arousal-related pattern. Therefore, expected surprise affects anticipatory and visually-guided responses differently. Moreover, these observations suggest a causal chain linking surprise, attention and saccades that could be disrupted in attentional or impulse control disorders.
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D'hondt S, Aujoulat I, Degryse JM. Development and Validation of a Revised Ambivalent Ageism Scale for Use in the Health Care Sector: The AAShc. THE GERONTOLOGIST 2024; 64:gnad136. [PMID: 37846520 DOI: 10.1093/geront/gnad136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Indexed: 10/18/2023] Open
Abstract
BACKGROUND AND OBJECTIVES The aim of this study was to adapt and validate the Ambivalent Ageism Scale (AAS) among paramedical students for use in the health care sector. RESEARCH DESIGN AND METHODS A cross-sectional study was conducted among the following paramedical students: physiotherapy, occupational therapy, and nursing students. A total of 6 items were added based on the literature and the scale was evaluated by students and professors with experience working with older adults. The following psychometric properties were evaluated: internal consistency, concurrent validity, structural validity (exploratory factor analysis), and reliability. RESULTS A total of 265 students participated: 19.2% physiotherapy students, 27.5% occupational therapy students, 50.6% nursing students, and 2.6% other paramedical students. The concurrent validity study showed a significant correlation between AAShc (Ambivalent Ageism Scale in the health care sector) and UCLA-GAS-F (French version of the University of California, Los Angeles Geriatric Attitudes Scale) with r (265) = 0.491 (p < .001). The factor analyses produced an 18-item (α = 0.866) scale composed of 5 factors: Infantilization (5 items, α = 0.766), Control (2 items, α = 0.789), Overaccommodation (2 items, α = 0.829), Unwanted help (2 items, α = 0.656), and Hostile Ageism (7 items, α = 0.717). Finally, the generalizability analysis revealed a G-coefficient of 0.86, a Phi-coefficient of 0.83, and a standard error of measurement of 2.31%. DISCUSSION AND IMPLICATIONS The AAShc appears to be a valid and reliable scale to measure ageism among paramedical students. This scale can be a useful tool to reduce ageism toward older adults in the health care sector.
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