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Faithful transfer of parental histones to newly replicated daughter DNA strands is critical for inheritance of epigenetic states. Although replication proteins that facilitate parental histone transfer have been identified, how intact histone H3-H4 tetramers travel from the front to the back of the replication fork remains unknown. Here, we use AlphaFold-Multimer structural predictions combined with biochemical and genetic approaches to identify the Mrc1/CLASPIN subunit of the replisome as a histone chaperone. Mrc1 contains a conserved histone-binding domain that forms a brace around the H3-H4 tetramer mimicking nucleosomal DNA and H2A-H2B histones, is required for heterochromatin inheritance, and promotes parental histone recycling during replication. We further identify binding sites for the FACT histone chaperone in Swi1/TIMELESS and DNA polymerase α that are required for heterochromatin inheritance. We propose that Mrc1, in concert with FACT acting as a mobile co-chaperone, coordinates the distribution of parental histones to newly replicated DNA.
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Chromatin-based epigenetic memory relies on the symmetric distribution of parental histones to newly synthesized daughter DNA strands, aided by histone chaperones within the DNA replication machinery. However, the mechanism of parental histone transfer remains elusive. Here, we reveal that in fission yeast, the replisome protein Mrc1 plays a crucial role in promoting the transfer of parental histone H3-H4 to the lagging strand, ensuring proper heterochromatin inheritance. In addition, Mrc1 facilitates the interaction between Mcm2 and DNA polymerase alpha, two histone-binding proteins critical for parental histone transfer. Furthermore, Mrc1's involvement in parental histone transfer and epigenetic inheritance is independent of its known functions in DNA replication checkpoint activation and replisome speed control. Instead, Mrc1 interacts with Mcm2 outside of its histone-binding region, creating a physical barrier to separate parental histone transfer pathways. These findings unveil Mrc1 as a key player within the replisome, coordinating parental histone segregation to regulate epigenetic inheritance.
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The eukaryotic replisome, organized around the Cdc45-MCM-GINS (CMG) helicase, orchestrates chromosome replication. Multiple factors associate directly with CMG, including Ctf4 and the heterotrimeric fork protection complex (Csm3/Tof1 and Mrc1), which has important roles including aiding normal replication rates and stabilizing stalled forks. How these proteins interface with CMG to execute these functions is poorly understood. Here we present 3 to 3.5 Å resolution electron cryomicroscopy (cryo-EM) structures comprising CMG, Ctf4, and the fork protection complex at a replication fork. The structures provide high-resolution views of CMG-DNA interactions, revealing a mechanism for strand separation, and show Csm3/Tof1 "grip" duplex DNA ahead of CMG via a network of interactions important for efficient replication fork pausing. Although Mrc1 was not resolved in our structures, we determine its topology in the replisome by cross-linking mass spectrometry. Collectively, our work reveals how four highly conserved replisome components collaborate with CMG to facilitate replisome progression and maintain genome stability.
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Proteínas de Unión al ADN/ultraestructura , Proteínas de Mantenimiento de Minicromosoma/ultraestructura , Proteínas Nucleares/ultraestructura , Proteínas de Saccharomyces cerevisiae/ultraestructura , Proteínas de Ciclo Celular/metabolismo , Microscopía por Crioelectrón/métodos , ADN Helicasas/genética , Replicación del ADN/genética , Replicación del ADN/fisiología , ADN de Hongos/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Mantenimiento de Minicromosoma/metabolismo , Proteínas Nucleares/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismoRESUMEN
Programmed fork pausing is a complex process allowing cells to arrest replication forks at specific loci in a polar manner. Studies in budding yeast and other model organisms indicate that such replication fork barriers do not act as roadblocks passively impeding fork progression but rather elicit complex interactions between fork and barrier components. In this issue of Genes & Development, Shyian and colleagues (pp. 87-98) show that in budding yeast, the fork protection complex Tof1-Csm3 interacts physically with DNA topoisomerase I (Top1) at replication forks through the C-terminal domain of Tof1. Fork pausing at the ribosomal DNA (rDNA) replication fork barrier (RFB) is impaired in the absence of Top1 or in a tof1 mutant that does not bind Top1, but the function of Top1 can be partially compensated for by Top2. Together, these data indicate that topoisomerases play an unexpected role in the regulation of programmed fork pausing in Saccharomyces cerevisiae.
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ADN-Topoisomerasas de Tipo I , Proteínas de Saccharomyces cerevisiae , Proteínas de Ciclo Celular , Replicación del ADN , Proteínas de Unión al ADNRESUMEN
Replication forks temporarily or terminally pause at hundreds of hard-to-replicate regions around the genome. A conserved pair of budding yeast replisome components Tof1-Csm3 (fission yeast Swi1-Swi3 and human TIMELESS-TIPIN) act as a "molecular brake" and promote fork slowdown at proteinaceous replication fork barriers (RFBs), while the accessory helicase Rrm3 assists the replisome in removing protein obstacles. Here we show that the Tof1-Csm3 complex promotes fork pausing independently of Rrm3 helicase by recruiting topoisomerase I (Top1) to the replisome. Topoisomerase II (Top2) partially compensates for the pausing decrease in cells when Top1 is lost from the replisome. The C terminus of Tof1 is specifically required for Top1 recruitment to the replisome and fork pausing but not for DNA replication checkpoint (DRC) activation. We propose that forks pause at proteinaceous RFBs through a "sTOP" mechanism ("slowing down with topoisomerases I-II"), which we show also contributes to protecting cells from topoisomerase-blocking agents.
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Replicación del ADN/genética , ADN-Topoisomerasas/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Ciclo Celular/metabolismo , ADN Helicasas/metabolismo , ADN-Topoisomerasas de Tipo I/metabolismo , Proteínas de Unión al ADN/metabolismo , Mutación , Transporte de Proteínas , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismoRESUMEN
The role of visit-to-visit variability of a biomarker in predicting related disease has been recognized in medical science. Existing measures of biological variability are criticized for being entangled with random variability resulted from measurement error or being unreliable due to limited measurements per individual. In this article, we propose a new measure to quantify the biological variability of a biomarker by evaluating the fluctuation of each individual-specific trajectory behind longitudinal measurements. Given a mixed-effects model for longitudinal data with the mean function over time specified by cubic splines, our proposed variability measure can be mathematically expressed as a quadratic form of random effects. A Cox model is assumed for time-to-event data by incorporating the defined variability as well as the current level of the underlying longitudinal trajectory as covariates, which, together with the longitudinal model, constitutes the joint modeling framework in this article. Asymptotic properties of maximum likelihood estimators are established for the present joint model. Estimation is implemented via an Expectation-Maximization (EM) algorithm with fully exponential Laplace approximation used in E-step to reduce the computation burden due to the increase of the random effects dimension. Simulation studies are conducted to reveal the advantage of the proposed method over the two-stage method, as well as a simpler joint modeling approach which does not take into account biomarker variability. Finally, we apply our model to investigate the effect of systolic blood pressure variability on cardiovascular events in the Medical Research Council elderly trial, which is also the motivating example for this article.
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Modelos Estadísticos , Humanos , Anciano , Estudios Longitudinales , Modelos de Riesgos Proporcionales , Simulación por Computador , BiomarcadoresRESUMEN
The chromosomal cohesin complex establishes sister chromatid cohesion during S phase, which forms the basis for faithful segregation of DNA replication products during cell divisions. Cohesion establishment is defective in the absence of either of three non-essential Saccharomyces cerevisiae replication fork components Tof1-Csm3 and Mrc1. Here, we investigate how these conserved factors contribute to cohesion establishment. Tof1-Csm3 and Mrc1 serve known roles during DNA replication, including replication checkpoint signaling, securing replication fork speed, as well as recruiting topoisomerase I and the histone chaperone FACT. By modulating each of these functions independently, we rule out that one of these known replication roles explains the contribution of Tof1-Csm3 and Mrc1 to cohesion establishment. Instead, using purified components, we reveal direct and multipronged protein interactions of Tof1-Csm3 and Mrc1 with the cohesin complex. Our findings open the possibility that a series of physical interactions between replication fork components and cohesin facilitate successful establishment of sister chromatid cohesion during DNA replication.
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Replicación del ADN , Proteínas de Saccharomyces cerevisiae , Proteínas de Unión al ADN/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Ciclo Celular/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Cromátides/metabolismo , CohesinasRESUMEN
INTRODUCTION/AIMS: Amyotrophic lateral sclerosis (ALS) exhibits selective muscle weakness. The weak shoulder and arm sparing signs, assessed by a single experienced neurologist, have been reported to be superior to previous signs in sensitivity and specificity. However, it is unknown whether the same results are observed when assessed by multiple neurologists. METHODS: Subjects were retrospectively identified from our department's inpatient database from 2014 to 2023. Medical Research Council (MRC) scores of the deltoid (Del), biceps brachii (BB), triceps brachii (TB), and first dorsal interosseous (FDI) muscles were evaluated. The weak shoulder sign was defined as positive when Del was weaker than BB and TB. The arm sparing sign was defined as positive when both Del and FDI were weaker than BB and TB. Sensitivity was analyzed in all ALS patients and in subgroups based on the region of symptom onset, presence or absence of upper motor neuron (UMN) signs, and the Japanese ALS Severity Classification. RESULTS: Seventy-one patients with ALS were identified. Eight neurologists and three neurology residents evaluated each patient's MRC scores. The weak shoulder and arm sparing signs were observed in 72% and 48% of patients, respectively, with no significant difference in sensitivity across patient subgroups. DISCUSSION: The weak shoulder and arm sparing signs showed high and moderate sensitivity, respectively, consistent with a previous report, even when evaluated by multiple examiners. This expands the clinical utility and increases the reliability of these signs, potentially contributing to accurate ALS diagnosis when combined with other clinical features and objective assessments.
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Malaria, a devastating disease, has claimed numerous lives and caused considerable suffering, with young children and pregnant women being the most severely affected group. However, the emergence of multidrug-resistant strains of Plasmodium and the adverse side effects associated with existing antimalarial drugs underscore the urgent need for the development of novel, well-tolerated, and more efficient drugs to combat this global health threat. To address these challenges, six new hydantoins derivatives were synthesized and evaluated for their in vitro antiplasmodial activity. Notably, compound 2c exhibited excellent inhibitory activity against the tested Pf3D7 strain, with an IC50 value of 3.97 ± 0.01 nM, three-fold better than chloroquine. Following closely, compound 3b demonstrated an IC50 value of 27.52 ± 3.37 µM against the Pf3D7 strain in vitro. Additionally, all the hydantoins derivatives tested showed inactive against human MCR-5 cells, with an IC50 value exceeding 100 µM. In summary, the hydantoin derivative 2c emerges as a promising candidate for further exploration as an antiplasmodial compound.
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Antimaláricos , Hidantoínas , Malaria , Embarazo , Niño , Femenino , Humanos , Preescolar , Plasmodium falciparum , Cloroquina/farmacología , Malaria/tratamiento farmacológico , Hidantoínas/farmacologíaRESUMEN
BACKGROUND: Approximately 1.3 billion people worldwide face barriers in accessing inclusive healthcare due to disabilities, leading to worse health outcomes, particularly in low and middle-income countries (LMIC). However, there is a lack of training of healthcare workers about disability, both globally and in Uganda. OBJECTIVES: To use mixed research methods to develop a comprehensive training program with standardisedelements for healthcare workers in Uganda, focusing on improving their knowledge, attitudes, and skills inproviding care for people with disabilities. METHODS: The Medical Research Council (MRC) approach was employed to guide the development of the training intervention. We conducted an umbrella review to gather relevant literature on disability training for healthcare workers. Interviews were conducted with international experts to gain insights and perspectives on the topic. Additionally, interviews were undertaken with people with disabilities and healthcare workers in Uganda to understand their experiences and needs. A participatory workshop was organised involving key stakeholders, to collaboratively design the training material based on the findings from these data sources. RESULTS: Eight review articles examined training programs for healthcare workers on disability. Training settings ranged from specialised clinical settings to non-clinical settings, and the duration and evaluation methods of the training varied widely. Lectures and didactic methods were commonly used, often combined with other approaches such as case studies and simulations. The impact of the training was assessed through healthcare worker reports on attitudes, knowledge, and self-efficacy. Interviews emphasised the importance of involving people with disabilities in the training and improving communication and understanding between healthcare providers and people with disabilities. Five themes for a training on disability for healthcare workers were generated through the workshop, including responsibilities and rights, communication, informed consent, accommodation, and referral and connection, which were used to guide the development of the curriculum, training materials and training approach. CONCLUSION: This study presents a novel approach to develop a training program that aims to enhance healthcare services for people with disabilities in Uganda. The findings offer practical insights for the development of similar programs in LMICs. The effectiveness of the training program will be evaluated through a pilot test, and policy support is crucial for its successful implementation at scale.
KEY MESSAGES: 1. Healthcare workers require training to effectively address the health concerns of people with disabilities, yet this is rarely included in curricula worldwide. 2. Uganda recognises the importance of addressing this issue and is taking steps to improve training programs about disability for healthcare workers. 3. We used multiple research methods (umbrella review, semi-structured interviews, participatory research and collaborative design) to co-develop a comprehensive training program with standardised elements for healthcare workers in Uganda, focusing on improving their knowledge, attitudes, and skills in providing care for people with disabilities. 4. The developed training material could be adapted for healthcare workers in other resource-limited settings, and policy support is needed to ensure its implementation at scale.
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Personas con Discapacidad , Personal de Salud , Humanos , Uganda , Personal de Salud/educación , Atención a la Salud , ActitudRESUMEN
In response to DNA replication stress, DNA replication checkpoint kinase Mec1 phosphorylates Mrc1, which in turn activates Rad53 to prevent the generation of deleterious single-stranded DNA, a process that remains poorly understood. We previously reported that lagging-strand DNA synthesis proceeds farther than leading strand in rad53-1 mutant cells defective in replication checkpoint under replication stress, resulting in the exposure of long stretches of the leading-strand templates. Here, we show that asymmetric DNA synthesis is also observed in mec1-100 and mrc1-AQ cells defective in replication checkpoint but, surprisingly, not in mrc1∆ cells in which both DNA replication and checkpoint functions of Mrc1 are missing. Furthermore, depletion of either Mrc1 or its partner, Tof1, suppresses the asymmetric DNA synthesis in rad53-1 mutant cells. Thus, the DNA replication checkpoint pathway couples leading- and lagging-strand DNA synthesis by attenuating the replication function of Mrc1-Tof1 under replication stress.
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Proteínas de Ciclo Celular/metabolismo , Quinasa de Punto de Control 2/metabolismo , Replicación del ADN/fisiología , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Ciclo Celular/genética , Quinasa de Punto de Control 2/genética , Replicación del ADN/genética , ADN de Hongos/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Fosforilación , Proteínas Serina-Treonina Quinasas/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomycetales/genética , Saccharomycetales/metabolismoRESUMEN
Paraquat (PQ) is a commercially important and effective herbicide in the world. Nevertheless, it has higher toxicity causing acute organ damage and different complications, mainly in the lungs and kidneys. Ferulic acid (FA), 4-hydroxy-3-methoxycinnamic acid imposes multiple pharmacological impacts. No protective effect of FA on PQ poisoning-caused human embryonic lung fibroblast damage has not been reported. Despite their many beneficial effects, FA is characterized by poor water solubility, low bioavailability, and phytochemical instability. To solve the problem, ß-cyclodextrin nanosponge (ß-CD NSs) was utilized to increase the solubility of FA so that it was grafted into ß-CD NSs to establish ß-CD@FA NSs. The purpose of this work was to examine for the first time the protective effect of ß-CD@FA NS on MRC-5 human lung cells damages induced by PQ poisoning. MTS assay was performed to investigate the viability of MRC-5 cells at different concentrations of FA/ß-CD@FA NSs when cells were co-cultured with 0.2 µg/mL PQ. The flow cytometry study was carried out to determine apoptosis. Malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) levels were detected using appropriate biochemistry kits. Compared with the PQ group, the cell activity, CAT, and SOD levels were significantly increased in the FA and chiefly in ß-CD@FA NSs intervention groups, whereas apoptosis and MDA levels were markedly decreased. The inflammatory factors tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), and interleukin 22 (IL-22) were detected. The results demonstrate that ß-CD@FA NSs can inhibit PQ-induced cell damage by enhancing antioxidant stress capacity and regulation of inflammatory responses.
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Paraquat , beta-Ciclodextrinas , Humanos , Paraquat/toxicidad , Pulmón , beta-Ciclodextrinas/farmacología , Superóxido Dismutasa/metabolismo , Estrés OxidativoRESUMEN
Road cracks significantly affect the serviceability and safety of roadways, especially in mountainous terrain. Traditional inspection methods, such as manual detection, are excessively time-consuming, labor-intensive, and inefficient. Additionally, multi-function detection vehicles equipped with diverse sensors are costly and unsuitable for mountainous roads, primarily because of the challenging terrain conditions characterized by frequent bends in the road. To address these challenges, this study proposes a customized Unmanned Aerial Vehicle (UAV) inspection system designed for automatic crack detection. This system focuses on enhancing autonomous capabilities in mountainous terrains by incorporating embedded algorithms for route planning, autonomous navigation, and automatic crack detection. The slide window method (SWM) is proposed to enhance the autonomous navigation of UAV flights by generating path planning on mountainous roads. This method compensates for GPS/IMU positioning errors, particularly in GPS-denied or GPS-drift scenarios. Moreover, the improved MRC-YOLOv8 algorithm is presented to conduct autonomous crack detection from UAV imagery in an on/offboard module. To validate the performance of our UAV inspection system, we conducted multiple experiments to evaluate its accuracy, robustness, and efficiency. The results of the experiments on automatic navigation demonstrate that our fusion method, in conjunction with SWM, effectively enables real-time route planning in GPS-denied mountainous terrains. The proposed system displays an average localization drift of 2.75% and a per-point local scanning error of 0.33 m over a distance of 1.5 km. Moreover, the experimental results on the road crack detection reveal that the MRC-YOLOv8 algorithm achieves an F1-Score of 87.4% and a mAP of 92.3%, thus surpassing other state-of-the-art models like YOLOv5s, YOLOv8n, and YOLOv9 by 1.2%, 1.3%, and 3.0% in terms of mAP, respectively. Furthermore, the parameters of the MRC-YOLOv8 algorithm indicate a volume reduction of 0.19(×106) compared to the original YOLOv8 model, thus enhancing its lightweight nature. The UAV inspection system proposed in this study serves as a valuable tool and technological guidance for the routine inspection of mountainous roads.
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In this study, we investigated reconfigurable intelligent surface (RIS)-assisted device-to-device (D2D) communication systems over Nakagami-m fading channels. To enhance the reliability of RIS-assisted D2D communications, we utilized the rate-splitting multiple access (RSMA) technique to maximize the achievable ergodic rate for our considered systems. Specifically, both devices decoded the common symbol by treating private symbols as interference, and then each private symbol was decoded by treating the other as interference. In order to maximize the achievable ergodic rate at the destination, we analyzed the achievable ergodic rate of the RIS link and the D2D link, and the destination jointly decoded both symbols transmitted from the source and device by involving the maximum ratio combination (MRC). We obtained a closed-form expression for the achievable ergodic rate of the proposed RIS-assisted D2D communication system. Finally, we investigated the influence of power allocation factors and the number of reflective elements on the achievable ergodic rate. As seen by the numerical results, there was a good match between the analysis and simulation results, as well as significant superiority compared with existing works.
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Paraquat (PQ) herbicide poisoning is a severe medical problem in developing countries without suitable therapy. This study aimed to investigate the effects of crocin (CCN) and nano crocin (NCCN) on PQ -induced toxicity in the MRC-5 cell line. The results showed that the particle size of NCCN was 140.3 ± 18.0 nm, and the zeta potential of the optimal crocin-loaded niosomes was 23.4 ± 2.8 mV. The NCCN was more effective than CCN in the inhibition of PQ-induced toxicity. Treatment of the MRC-5 cells leads to a decrease in ROS and an increase in SOD, CAT, GPX, and TAC levels in PQ-CCN and PQ-NCCN groups compared with the PQ group. These changes tended to be positively associated with the NCCN compared to CCN. Overall, NCCN was more effective than crocin in treating PQ-induced toxicity in vitro and deserved further preclinical consideration.
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Chronic kidney disease (CKD) is one of the non-infectious diseases that threaten patients' lives on a daily basis. Its prevalence is high, but under-reported by patients and those living with the disease, as it is silent and asymptomatic in the early stages. Kidney disease increases the risk of heart and vascular disease. These problems can manifest themselves slowly, over a long period of time. Early detection and treatment can often prevent chronic kidney disease from worsening. As kidney disease progresses, it can lead to kidney failure, requiring dialysis or a kidney transplant to stay alive. In this narrative review, we will mainly discuss different treatment option costs in different countries and how much they cost healthcare systems in countries in three different continents.
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Diálisis Renal , Insuficiencia Renal Crónica , Humanos , Insuficiencia Renal Crónica/epidemiología , Insuficiencia Renal Crónica/terapia , África/epidemiología , Costos de la Atención en Salud , Asia/epidemiologíaRESUMEN
Osteosarcoma is one of the most common orthopedic malignancies and is characterized by rapid disease progression and a poor prognosis. Currently, research on methods to inhibit osteosarcoma proliferation is still limited. In this study, we found that MST4 levels were significantly increased in osteosarcoma cell lines and tumor tissues compared to normal controls and demonstrated that MST4 is an influential factor in promoting osteosarcoma proliferation both in vivo and in vitro. Proteomic analysis was performed on osteosarcoma cells in the MST4 overexpression and vector expression groups, and 545 significantly differentially expressed proteins were identified and quantified. The candidate differentially expressed protein MRC2 was then identified using parallel reaction monitoring validation. Subsequently, MRC2 expression was silenced with small interfering RNA (siRNA), and we were surprised to find that this alteration affected the cell cycle of MST4-overexpressing osteosarcoma cells, promoted apoptosis and impaired the positive regulation of osteosarcoma growth by MST4. In conclusion, this study identified a novel approach for suppressing osteosarcoma proliferation. Reduction of MRC2 activity inhibits osteosarcoma proliferation in patients with high MST4 expression by altering the cell cycle, which may be valuable for treating osteosarcoma and improving patient prognosis.
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Neoplasias Óseas , Osteosarcoma , Humanos , Proteínas Serina-Treonina Quinasas/genética , Proteómica , Osteosarcoma/patología , ARN Interferente Pequeño/genética , Neoplasias Óseas/metabolismo , Proliferación Celular/genética , Línea Celular TumoralRESUMEN
The expansion of the geographical footprint of dengue viruses (DENVs) and their mosquito vectors have affected more than half of the global population, including older adults who appear to show elevated risk of severe dengue. Despite this epidemiological trend, how aging contributes to increased dengue pathogenesis is poorly understood. A limitation has been the lack of useful in vitro experimental approaches; cell lines commonly used for infection studies are immortal and hence do not age. Cell strains such as WI-38 and MRC-5 with diploid genomes do age with in vitro passaging, but these cell strains were isolated decades ago and are now mostly highly passaged. Here, we show that reprogramming of cell strains with finite life span into induced pluripotent stem cells (iPSCs), followed by conversion back into terminally differentiated cells, can be an approach to derive genetically identical cells at different stages of aging. The iPSC-derived differentiated cells were susceptible to wild-type DENV infection and produced greater levels of type I interferon expression with increased passaging, despite similar levels of infection. In contrast, infection with the attenuated DENV-2 PDK53 and YF17D-204 strains showed reduced and increased levels of infection with increasing passages, respectively; the latter could be clinically pertinent, as YF17D-204 vaccination in older adults is associated with increased risk of severe adverse outcome. The differences in infection susceptibility and host response collectively suggest the potential of iPSC-derived cell strains as a genetically controlled approach to understanding how aging impacts viral pathogenesis. IMPORTANCE Aging has been a risk factor for poor clinical outcome in several infectious diseases, including dengue. However, age-dependent responses to dengue and other flaviviral infection or vaccination have remained incompletely understood due partly to lack of suitable laboratory tools. We thus developed an in vitro approach to examine age-related changes in host response to flaviviral infection. Notably, this approach uses cell strains with diploid rather than aneuploidic genomes, which are unstable. Conversion of these cells into iPSCs ensures sustainability of this resource, and reprogramming back into terminally differentiated cells would, even with a limited number of passages, produce cells at different stages of aging for infection studies. Our findings suggest that this in vitro system has the potential to serve as a genetically controlled approach to define the age-related response to flavivirus infection.
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Infecciones por Flavivirus/metabolismo , Infecciones por Flavivirus/virología , Flavivirus/fisiología , Interacciones Huésped-Patógeno , Células Madre Pluripotentes Inducidas/metabolismo , Células Madre Pluripotentes Inducidas/virología , Factores de Edad , Diferenciación Celular , Células Cultivadas , Senescencia Celular/genética , Senescencia Celular/inmunología , Dengue/virología , Virus del Dengue , Femenino , Fibroblastos/citología , Fibroblastos/metabolismo , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/inmunología , Humanos , MasculinoRESUMEN
BACKGROUND AND PURPOSE: Measuring health-related quality of life (QOL) is vital for understanding the disease impact, but the complex relationship between clinical parameters and QOL remains unclear. The objective was to determine the demographic and clinical factors that influence the QOL in adults with inherited and acquired myopathies. METHODS: The study was of cross-sectional design. Detailed demographic and clinical details were collected. Patients answered Neuro-QOL and Patient-Reported Outcomes Measurement Information System short-form questionnaires. RESULTS: Data was collected from 100 consecutive in-person patient visits. Mean age of the cohort was 49.5 ± 20.1 (18-85) years, and the majority were male (53, 53%). Bivariate analysis between the various demographic and clinical features with the QOL scales revealed single simple question (SSQ), handgrip strength, Medical Research Council (MRC) sum score, female gender, and age to be nonuniformly associated with the QOL scales. There was no difference between inherited and acquired myopathies for any of the QOL scores, except for the poorer lower limb function domain in inherited myopathies (36.7 ± 7.3 vs. 40.9 ± 11.2, p = 0.049). Linear regression models revealed lower SSQ, lower handgrip strength, and lower MRC sum score to independently predict poor QOL. CONCLUSIONS: Handgrip strength and SSQ serve as novel predictors of QOL in myopathies. Handgrip strength has a significant impact on physical, mental, and social domains and deserves special attention with respect to rehabilitation. SSQ correlates well with QOL and can be employed as a quick and global assessment of a patient's well-being. Differences in QOL scores between patients with inherited and acquired myopathies were minimal.
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Enfermedades Musculares , Calidad de Vida , Humanos , Adulto , Masculino , Femenino , Persona de Mediana Edad , Anciano , Estudios Transversales , Fuerza de la Mano , Encuestas y CuestionariosRESUMEN
The urokinase plasminogen activator receptor-associated protein (uPARAP/Endo180) is already known to be a key collagen receptor involved in collagen internalization and degradation in mesenchymal cells and some macrophages. It is one of the four members of the mannose receptor family along with a macrophage mannose receptor (MMR), a phospholipase lipase receptor (PLA2R), and a dendritic receptor (DEC-205). As a clathrin-dependent endocytic receptor for collagen or large collagen fragments as well as through its association with urokinase (uPA) and its receptor (uPAR), uPARAP/Endo180 takes part in extracellular matrix (ECM) remodeling, cell chemotaxis and migration under physiological (tissue homeostasis and repair) and pathological (fibrosis, cancer) conditions. Recent advances that have shown an expanded contribution of this multifunctional protein across a broader range of biological processes, including vascular biology and innate immunity, are summarized in this paper. It has previously been demonstrated that uPARAP/Endo180 assists in lymphangiogenesis through its capacity to regulate the heterodimerization of vascular endothelial growth factor receptors (VEGFR-2 and VEGFR-3). Moreover, recent findings have demonstrated that it is also involved in the clearance of collectins and the regulation of the immune system, something which is currently being studied as a biomarker and a therapeutic target in a number of cancers.