Search Results (159)

Background: Duchenne muscular dystrophy (DMD), which affects 1 in 3500 to 5000 newborn boys worldwide, is characterized by progressive skeletal muscle weakness and degeneration. The reduced muscle regeneration capacity presented by patients is associated with increased fibrosis. Satellite cells (SCs) are skeletal muscle stem cells that play an important role in adult muscle maintenance and regeneration. The absence or mutation of dystrophin in DMD is hypothesized to impair SC asymmetric division, leading to cell cycle arrest. Methods: To overcome the limited availability of biopsies from DMD patients, we used our 3D skeletal muscle organoid (SMO) system, which delivers a stable population of myogenic progenitors (MPs) in dormant, activated, and committed stages, to perform SMO cultures using three DMD patient-derived iPSC lines. Results: The results of scRNA-seq analysis of three DMD SMO cultures versus two healthy, non-isogenic, SMO cultures indicate reduced MP populations with constant activation and differentiation, trending toward embryonic and immature myotubes. Mapping our data onto the human myogenic reference atlas, together with primary SC scRNA-seq data, indicated a more immature developmental stage of DMD organoid-derived MPs. DMD fibro-adipogenic progenitors (FAPs) appear to be activated in SMOs. Conclusions: Our organoid system provides a promising model for studying muscular dystrophies in vitro, especially in the case of early developmental onset, and a methodology for overcoming the bottleneck of limited patient material for skeletal muscle disease modeling. Full article

User churn in online games refers to players becoming inactive for an extended period. Even a small increase in churn can lead to significant revenue loss, making churn prediction crucial for sustaining long-term player engagement. Although user churn prediction has been extensively studied, most existing approaches either ignore non-login periods or treat all inactivity uniformly, overlooking key behavioral differences. This study addresses this gap by categorizing non-login periods into three types, as follows: inactivity due to new or dormant users, genuine loss of interest, and temporary inaccessibility caused by external factors. These periods are treated as either non-existent or missing data and imputed using techniques such as mean or mode substitution, linear interpolation, and multiple imputation by chained equations (MICE). MICE was selected due to its ability to impute missing values more robustly by considering multivariate relationships. A random forest (RF) classifier, chosen for its interpretability and robustness to incomplete data, serves as the primary prediction model. Additionally, classifier chains are used to capture label dependencies, and principal component analysis (PCA) is applied to reduce dimensionality and mitigate overfitting. Experiments on real-world MMORPG data show that our approach improves predictive accuracy, achieving a micro-averaged AUC of above 0.92 and a weighted F1 score exceeding 0.70. These findings suggest that our approach improves churn prediction and offers actionable insights for supporting personalized player retention strategies. Full article

Dormancy occurs when Mycobacterium tuberculosis (Mtb) enters a non-replicating and metabolically inactive state in response to hostile environment. During this state, it is highly resistant to conventional antibiotics, which increase the urgency to develop new potential drugs against dormant bacilli. In view of this, the dormancy survival regulator (DosR) protein is thought to be an essential component that plays a key role in bacterial adaptation to dormancy during hypoxic conditions. Herein, the NP-lib database containing natural product compounds was screened virtually against the binding site of the DosR protein using the MTiopen screen web server. A series of computational analyses were performed, including redocking, intermolecular interaction analysis, and MDS, followed by binding free energy analysis. Through screening, 1000 natural product compounds were obtained with docking energy ranging from −8.5 to −4.1 kcal/mol. The top four lead compounds were then selected for further investigation. On comparative analysis of intermolecular interaction, dynamics simulation and MM/GBSA calculation revealed that M3 docked with the DosR protein (docking score = −8.1 kcal/mol, RMSD = ~7 Å and ΔG Bind = −53.51 kcal/mol) exhibited stronger stability than reference compound Ursolic acid (docking score = −6.2 kcal/mol, RMSD = ~13.5 Å and ΔG Bind = −44.51 kcal/mol). Hence, M3 is recommended for further validation through in vitro and in vivo studies against latent tuberculosis infection. Full article

Background/Objectives: Malaria, caused by infection with Plasmodium parasites, exacts a heavy toll worldwide. There are two licensed vaccines for malaria as well as two monoclonal antibodies that have shown promising efficacy in field trials. The vaccines and monoclonal antibodies target the major surface protein (circumsporozoite protein, CSP) of Plasmodium falciparum. Yet P. falciparum is only one of the four major species of Plasmodium that infect humans. Plasmodium vivax is the second leading cause of malaria, but the P. vivax vaccine and monoclonal development lags far behind that for P. falciparum owing to the lack of basic preclinical tools such as in vitro culture or mouse models that replicate the key biological features of P. vivax. Notably among these features is the ability to form dormant liver stages (hypnozoites) that reactivate and drive the majority of the P. vivax malaria burden. Plasmodium cynomolgi is a simian parasite which is genotypically very close and phenotypically similar to P. vivax; it can infect non-human primates commonly used in research and replicates many features of P. vivax, including relapsing hypnozoites. Methods: Recently, a strain of P. cynomolgi has been adapted to in vitro cultures allowing parasite transgenesis. Here, we created a transgenic P. cynomolgi parasite in which the endogenous P. cynomolgi CSP has been replaced with P. vivax CSP, with the goal of enabling the preclinical study of anti-P. vivax CSP interventions to protect against primary and relapse infections. Results: We show that the in vitro-generated transgenic Pcy[PvCSP] parasite expresses both serotypes of P. vivax CSP and retains full functionality in vivo, including the ability to transmit to laboratory-reared Anopheles mosquitoes and cause relapsing infections in rhesus macaques. To our knowledge, this is the first gene replacement in a relapsing Plasmodium species. Conclusions: This work can directly enable the in vivo development of anti-P. vivax CSP interventions and provide a blueprint for the study of relapsing malaria through reverse genetics. Full article

This study investigates the germination ecology of three Lepidium species, including the invasive, indehiscent-fruited Lepidium appelianum and Lepidium draba, and the invasive, dehiscent-fruited Lepidium campestre. The ability of Lepidium species to germinate under a wide range of temperature conditions is significant for understanding their potential invasiveness and establishment in novel and extreme environments. This study aims to clarify the germination behavior of L. appelianum, L. draba, and L. campestre, thereby enhancing our understanding of their invasive potential and ecological implications in the context of a changing climate. The base (Tb), optimum (To), and maximum temperatures for 50% germination (Tc(50)) were determined across a broad thermal gradient following standard protocols. Freshly harvested seeds and fruits of L. appelianum are non-dormant. In contrast, L. draba exhibit pericarp-mediated chemical dormancy, while L. campestre demonstrates physiological dormancy, which is released through after-ripening. The results indicate that L. appelianum and L. draba seeds and fruits germinate at a base temperature (Tb) of 1 °C and 4 °C, respectively. On the other hand, L. campestre seeds germinate at a Tb of 5.8 °C. The optimum temperature (To) for the germination of seeds and fruits in L. appelianum and L. draba ranges from 23 °C to 25 °C, while the To for L. campestre seed germination is 16 °C to 18 °C. Additionally, the maximum temperature for 50% germination (Tc(50)) for L. appelianum fruits is 39.8 °C, for L. draba it is 34.4 °C, and L. campestre reports a (Tc(50)) ranging from 27.4 °C to 33.3 °C for freshly harvested and after-ripened seeds, respectively. These results demonstrated that L. appelianum and L. draba can germinate across a broad temperature range, from very cold to very hot, unlike L. campestre. These findings suggest that the unique reproductive strategy of indehiscent fruits, coupled with a wide thermal germination niche, may contribute to the invasive success of L. appelianum and L. draba. Given the projected climate warming, the results highlight the potential for increased invasiveness of these species and suggest the need for targeted management strategies. Full article

Cancer stem cells (CSCs) are a subpopulation with self-renewal and differentiation capacities believed to be responsible for tumor initiation, progression, and recurrence. These cells exhibit unique metabolic features that contribute to their stemness and survival in hostile tumor microenvironments. Like non-stem cancer cells, CSCs primarily rely on glycolysis for ATP production, akin to the Warburg effect. However, CSCs also show increased dependence on alternative metabolic pathways, such as oxidative phosphorylation (OXPHOS) and fatty acid metabolism, which provide necessary energy and building blocks for self-renewal and therapy resistance. The metabolic plasticity of CSCs enables them to adapt to fluctuating nutrient availability and hypoxic conditions within the tumor. Recent studies highlight the importance of these metabolic shifts in maintaining the CSC phenotype and promoting cancer progression. The CSC model suggests that a small, metabolically adaptable subpopulation drives tumor growth and therapy resistance. CSCs can switch between glycolysis and mitochondrial metabolism, enhancing their survival under stress and dormant states. Targeting CSC metabolism offers a promising therapeutic strategy; however, their adaptability complicates eradication. A multi-targeted approach addressing various metabolic pathways is essential for effective CSC elimination, underscoring the need for further research into specific CSC markers and mechanisms that distinguish their metabolism from normal stem cells for successful therapeutic intervention. Full article

Seed propagation is the primary means of reproducing many native and endemic species, including garberia [Garberia heterophylla (W. Bartram) Merrill & F. Harper]. This attractive pollinator plant, native to Florida, is scarcely found in nursery production and largely unknown to the gardening community. To better understand the seed biology of garberia, a series of experiments were conducted to evaluate the effects of population on seed viability and germination response to four seasonal temperatures, as well as the effects of time on seed storability. Initial seed viability was 49% and 60% for Central and North Florida populations, respectively. Seeds germinated readily, indicating non-dormancy, with significant effects of population and temperature observed. Overall, on day 28, a greater germination proportion was observed from seeds collected from North Florida than Central Florida across temperatures, except for winter (11/22 °C), where responses were similar. The greatest germination proportion for seeds collected from North Florida was observed at 15/27 °C (fall) and 19/29 °C (spring), whereas the greatest germination from Central Florida was observed at 11/22 °C (winter), with the steepest decline observed at summer temperatures (24/33 °C). Further, it was observed that garberia seeds are intolerant of long-term storage, losing viability as early as 3 months under conventional cold or room temperature storage and decreasing substantially more after 6 months. These findings contribute to the overall understanding of the seed biology of underutilized species such as garberia, key to the development of efficient and reliable propagation systems for our nursery industry. Full article

If lettuce is contaminated in the field, Shiga toxin-producing E. coli (STEC) O157:H7 can survive through the distribution chain. Prolonged cold storage during transportation may impact pathogen physiology, affecting subsequent stress survival and virulence. Greenhouse-grown Romaine lettuce, inoculated with three STEC O157:H7 strains, was harvested after 24 h and stored at 2 °C for 5 d following 4 h at harvest temperature (9 °C or 17 °C). Culturable, persister, and viable but non-culturable (VBNC) cells were quantified. Virulence was evaluated using Galleria mellonella and acid tolerance at pH 2.5 and tolerance to 20–25 ppm free chlorine were quantified. Colder harvest temperature (9 °C) before cold storage led to greater transformation of STEC O157:H7 into dormant states and decreased virulence in most cases. Increasing length of cold storage led to decreased virulence and acid tolerance of STEC O157:H7 on lettuce, while having no significant effect on chlorine tolerance. These findings highlight that entry of STEC O157:H7 into dormant states during harvest and transportation at cold temperatures leads to decreased stress tolerance and virulence with increasing cold storage. Changes in STEC O157:H7 physiology on lettuce during cold storage can be integrated into risk assessment tools for producers, which can assist in identifying practices that minimize risk of STEC O157:H7 from consumption of lettuce. Full article

In this work, metabolite profiling of seeds and antioxidant analysis of fragments of two marine seagrasses, Posidonia oceanica and Cymodocea nodosa, were carried out to identify metabolite signature involved in seed viability and to evaluate the potential of fragments as a source of bioactive compounds. Using HILIC/QTOF-MS, UHPLC-MS and spectrophotometric analysis, seed metabolites and polyphenols and antioxidant activities, such as those of radical scavenging (RSA), reduction (FRAP, CUPRAC) and complexation (CCA), of rhizome fragments were evaluated. Metabolite comparison between seeds revealed differences across development stages (germinated and non-germinated) and seed types (dormant and non-dormant), providing insights into metabolic activity potentially associated with germination processes and seed viability. Furthermore, polyphenol analysis showed the highest content of caffeic acid in mature leaves (17.00 ± 0.02 μg g⁻¹ dw for P. oceanica and 98.00 ± 0.03 μg g⁻¹ dw for C. nodosa). Total phenolic content was correlated with flavonoids and with reduction and complexation activities. The combination of radical scavenging activity and t_1/2 was higher in P. oceanica than C. nodosa and also surpassed the commercial synthetic antioxidant BHA. We conclude P. oceanica and C. nodosa exhibit distinct seed metabolite profiles related to germination and type of seeds, and that fragments are rich in antioxidants, with potential as sustainable sources of bioactive compounds. Full article

Alfalfa (Medicago sativa) is a globally distributed economic legume crop used for forage and ecological restoration. We aimed to explore the mechanisms underlying the cold acclimation observed in this species. Our results for fall plant growth showed that non-dormant alfalfa (SD) maintained a vigorous growth rate compared to that of fall-dormant alfalfa (ZD); however, the winter survival rate of ZD was higher than that of SD. Among the ZD samples, the starch content first accumulated and then decreased; the sucrose content was consumed first along with simultaneous raffinose accumulation, which was followed by sucrose content accumulation, with consistent changes in the corresponding related synthase and hydrolase activity. SD exhibited the opposite trend. The transcriptome data showed that most of the differentially expressed genes were involved in carbon metabolism (ko01200), amino acid biosynthesis (ko01230), and starch and sucrose metabolism (ko00500). Our data clearly show that alfalfa’s cold acclimation mechanism is a complex process, with the establishment of stable carbon homeostasis; sucrose is first converted into starch and raffinose, and then, starch is converted into sucrose, which enables alfalfa’s cold resistance. The process is accompanied by CBF/DREB1A TF regulation. This study provides important insights into the cold acclimation mechanisms of alfalfa. Full article

Background: This paper briefly reviews the most important endocrine features of primary ovarian insufficiency (POI) and shows their relevance for the diagnosis and treatment of this condition. Introduction: Endocrine disturbances in POI cause problems for both the fertility and general health status of the affected women. Both subfertility and infertility result from the depletion of growing ovarian follicles which, in its turn, is the causative factor of hypoestrogenism; this is responsible for most of the general health problems affecting women. Method: Search of literature. Results and conclusion: A combination of high-serum follicle-stimulating hormone (FSH) and low 17β-estradiol (E2) concentrations is a key feature characterizing POI and is the decisive element for POI diagnosis. However, an in-depth search for possible genetic and non-genetic causes is important for adequate counseling regarding prevention and early intervention. The treatment of general health problems, based on correcting hypoestrogenism through hormone replacement therapy (HRT), is relatively easy. On the other hand, resolving infertility is a much more difficult task, and oocyte donation is the only really efficient instrument. Fertility preservation is a suitable alternative in patients with early POI diagnosis, in whom some viable follicles are still present in the ovaries. In patients who refuse oocyte donation, intraovarian injection of autologous platelet-rich plasma and in vitro activation of dormant follicles may be considered. Other innovative treatments, such as stem cell therapies or nuclear transfer, are currently under investigation. Full article

Beaver populations in the U.S. northeast are rising, increasing the number of beaver dams and ponds in suburban watersheds. These new beaver ponds may impact the way that harmful algal blooms occur by changing biogeochemical cycling and sediment characteristics. In this study, piezometers, installed upstream and downstream of multiple dam structures were used to evaluate changes in nitrate and orthophosphate concentrations in surface and hyporheic water. Data were also collected with seepage meters, discharge measurements, lab and field-based analytical tests, and sediment samples. These were collected from beaver dams and paired non-beaver dams upstream of unimpounded reaches to look at the potential for dormant sediment-based cyanobacteria to bloom and produce toxins under ideal light and nutrient levels. Results indicate a significant increase in orthophosphate from upstream to downstream of beaver dams. Results also demonstrate that toxin potential did not increase between cyanobacteria in beaver pond sediment and the paired unimpounded sample; however, under ideal light and nutrient levels, sediment from a beaver dam led to faster cyanobacterial growth. These findings highlight that while beaver dams and impoundments function as nutrient sinks within the tributary watersheds, there are potential risks from downstream transport of bloom-inducing sediment following a dam collapse. Full article

Oxidative stress is prevalent in organisms, and excessive oxidative damage can trigger cell death. Bacteria have evolved multiple pathways to cope with adverse stress, including the regulation of the cell cycle. Previous studies show that non-lethal exposure to H₂O₂ and mutations in antioxidant enzymes suppress replication initiation in Escherichia coli. The existence of common regulatory factors governing replication initiation across diverse causes-induced oxidative stress remains unclear. In this study, we utilized flow cytometry to determine the replication pattern of E. coli, and found that oxidative stress also participated in the inhibition of replication initiation by a defective iron regulation (fur-bfr-dps deletion). Adding a certain level of ATP promoted replication initiation in various antioxidant enzyme-deficient mutants and the ΔfurΔbfrΔdps mutant, suggesting that low ATP levels could be a common factor in the inhibition of replication initiation by different causes-induced oxidative stress. More potential common factors were screened using proteomics, followed by genetic validation with H₂O₂ stress. We found that oxidative stress might mediate the inhibition of replication initiation by interfering with the metabolism of glycine, glutamate, ornithine, and aspartate. Blocking CcmA-dependent cytochrome c biosynthesis, deleting the efflux pump proteins MdtABCD and TolC, or the arabinose transporter AraFHG eliminated the replication initiation inhibition by H₂O₂. In conclusion, this study uncovers a common multifactorial pathway of different causes-induced oxidative stress inhibiting replication initiation. Dormant and persistent bacteria exhibit an arrested or slow cell cycle, and non-lethal oxidative stress promotes their formation. Our findings contribute to exploring strategies to limit dormant and persistent bacterial formation by maintaining faster DNA replication initiation (cell cycle progression). Full article

An efficient legal system facilitates the enforcement of guarantees, enables the recovery of non-performing loans and increases trust between creditors and borrowers. This study examines the effect of the legal environment and the profitability of the Angolan banking sector. Specifically, it analyses the influence of property rights and the rule of law on bank profitability in Angola. The study employs various econometric methods for analyzing panel data, such as Feasible Generalized Least Squares (FGLS), and instrumental variables models such as Two-Stage Least Squares (IV-2SLS), Generalized Method of Moments (IV-GMM) and Quantile Regression (MQREG). The study concludes that improving the legal environment by strengthening property rights and promoting the rule of law favours the profitability of Angolan banks. In terms of practical implications, this study shows that the legal environment in Angola is an important barrier to the promotion of credit in Angola, and, above all, to improving the profitability of banks. This study contributes to the scarce literature highlighting the relationship between the legal system and the Angolan banking sector, a topic that has been little explored in the context of African countries. Furthermore, the study awakens the dormant debate on the legal system and finance. Full article

Black locust (Fabaceae family) seeds are known for their strong dormant state and are an excellent candidate for studying and developing methods to break dormancy. We investigated overcoming the dormancy using several different sources of non-thermal plasma, which, by modifying, etching, or disrupting the waxy seed coat, allowed water to penetrate the seeds and initiate germination. All plasma sources tested enhanced seed germination to varying degrees, with over 80% germination observed when using a dielectric barrier discharge, while control seeds showed no germination. Non-thermal plasma treatment significantly decreased the water contact angle of the seed surface from an initial 120° (for untreated seeds) to complete wetting when using a dielectric barrier discharge or atmospheric-pressure plasma jet. The experiments indicate two mechanisms for the modification of the waxy seed coat by a non-thermal plasma: hydrophilization of the wax surface through the binding of oxygen particles and etching of narrow channels in the wax layer, allowing water to penetrate the seed. Full article