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RNA-binding proteins (RBPs), which regulate gene expression through post-transcriptional modifications of RNAs, play a role in diverse biological processes that include bone cell development and bone tissue formation. RBP dysregulation may result in aberrant bone homeostasis and contribute to various bone diseases. The function of RBPs in bone physiology and pathophysiology and the underlying molecular mechanisms have been extensively studied in recent years. This article provides a review of such studies, highlighting the potential of RBPs as pivotal targets for therapeutic intervention. [ABSTRACT FROM AUTHOR]

Mammalian hibernation is composed of multiple episodes of torpor bout, separated by phases of interbout arousal. During torpor, the skeletal muscles of mammals are undoubtedly inactive, but it has been proven to mitigate disuse atrophy. While interbout arousal has been implicated in the prevention of muscle atrophy, the underlying mechanisms sustaining muscle contraction remain to be explored. In the present study, Daurian ground squirrels (Spermophilus dauricus) were divided into four groups: pre-hibernation (PRE), torpor (TOR), interbout arousal (IBA), and post-hibernation (POST). The contractile performance of slow-twitch soleus muscle (SOL) and fast-twitch extensor digitorum longus muscle (EDL) was detected both in situ and in vitro. Concurrently, mitochondrial respiratory chain complex activity in these muscles was quantified. Our findings revealed that in situ contractile properties of both muscles, including force, power output, time duration, and force development/relaxation rates of twitch contraction, and force and power output of tetanic contraction declined in the TOR group compared to the PRE group, but improved in the IBA and POST groups. Fatigue resistance of muscles, determined by the power output of repetitive tetanic contractions in situ, decreased in the TOR group but recovered in the IBA and POST groups. In vitro studies demonstrated that tetanic contraction power output in isolated muscles increased with muscle temperature in both TOR and IBA groups. However, at the same temperature, power output was consistently lower in the TOR group compared to the IBA group. Moreover, the activity of the mitochondrial respiratory chain complex, especially Complexes I and II, decreased in the TOR group but showed recovery in the IBA and POST groups. These findings suggest that both the contractile performance and fatigue resistance of mammalian skeletal muscle are compromised during torpor but can be improved during interbout arousal and post-hibernation. The rebound in body temperature and rise in mitochondrial respiratory chain complex activity in skeletal muscle are involved in enhancing contractile performance and fatigue resistance. This study suggests that interbout arousal functions as a vital temporal interval during which skeletal muscles can transition from the inactivity induced by torpor to a state of restored contractile functionality. Thus, interbout arousal serves as a behavioral safeguard against disuse-induced damage to skeletal muscles during hibernation. [ABSTRACT FROM AUTHOR]

Simple Summary: Over the past 20 years, there has been a worldwide resurgence in the nuisance biting insects known as bed bugs. The resurgence is due to the development of insecticide resistance, such that modern bed bugs are very hard to kill. This also means that control is expensive, and not everyone has the financial resources to pay for eradication. In an effort to develop cheaper control solutions, we investigated the use of "lethal harborages". Here, pieces of cardboard were treated with different insecticides, two strains of bed bugs (one that is easy to kill and one that is resistant) were allowed to enter the treated cardboards, and mortality was recorded. The cardboard treated with silica dioxide were the most effective, causing 100% of the bugs to die within 14 to 17 days when using the highest dose. This silica dioxide dust was also tested in an artificial environment. By day 21, all the bugs in the treated settings were eliminated. These "lethal harborages" were highly effective in the laboratory and are a potential low-cost solution as part of an overall bed bug control plan. Over the past two decades, there has been a worldwide resurgence in the bed bugs Cimex lectularius L. and Cimex hemipterus (F.). This is primarily due to insecticide resistance, making bed bug management and eradication challenging and expensive. To address the need for more affordable control solutions, "lethal harborages" were explored. Cardboard squares were treated using insecticidal dusts at different dosage levels, including silica dioxide, diatomaceous earth, deltamethrin, permethrin, and fipronil. Two strains of C. lectularius, one susceptible and one resistant, were allowed to enter the treated harborages, and mortality rates were recorded daily. The silica dioxide products proved to be the most efficacious, consistently achieving 100% mortality between 14–17 d at the highest dose. An artificial environment trial using the "new ChinChex®" formulation of silica dioxide resulted in the complete elimination of bed bugs in the treated harborages within 21 d. These findings suggest that lethal harborages, especially those impregnated with silica dioxide, offer a cost-effective solution that could be incorporated into broader integrated bed bug management strategies. This approach may help alleviate the burden of bed bug infestations in economically disadvantaged communities. [ABSTRACT FROM AUTHOR]

Osteoporosis, a disease characterized by both loss of bone mass and structural deterioration of bone, is the most common reason for a broken bone among the elderly. It is known that the attenuated differentiation ability of osteogenic cells has been regarded as one of the greatest contributors to age-related bone formation reduction. However, the effects of current therapies are still unsatisfactory. In this study we identify a novel long noncoding RNA AK045490 which is correlated with osteogenic differentiation and enriched in skeletal tissues of mice. In vitro analysis of bone-derived mesenchymal stem cells (BMSCs) showed that AK045490 inhibited osteoblast differentiation. In vivo inhibition of AK045490 by its small interfering RNA rescued bone formation in ovariectomized osteoporosis mice model. Mechanistically, AK045490 inhibited the nuclear translocation of β-catenin and downregulated the expression of TCF1, LEF1, and Runx2. The results suggest that Lnc-AK045490 suppresses β-catenin/TCF1/Runx2 signaling and inhibits osteoblast differentiation and bone formation, providing a novel mechanism of osteogenic differentiation and a potential drug target for osteoporosis. [ABSTRACT FROM AUTHOR]

Skeletal systems provide support, movement, and protection to the human body. It can be affected by several life suffering bone disorders such as osteoporosis, osteoarthritis, and bone cancers. It is not an easy job to treat bone disorders because of avascular cartilage regions. Treatment with non-specific drug delivery must utilize high doses of systemic administration, which may result in toxicities in non-skeletal tissues and low therapeutic efficacy. Therefore, in order to overcome such limitations, developments in targeted delivery systems are urgently needed. Although the idea of a general targeted delivery system using bone targeting moieties like bisphosphonates, tetracycline, and calcium phosphates emerged a few decades ago, identification of carrier systems like viral and non-viral vectors is a recent approach. Viral vectors have high transfection efficiency but are limited by inducing immunogenicity and oncogenicity. Although non-viral vectors possess low transfection efficiency they are comparatively safe. A number of non-viral vectors including cationic lipids, cationic polymers, and cationic peptides have been developed and used for targeted delivery of DNA, RNA, and drugs to bone tissues or cells with successful consequences. Here we mainly discuss such various non-viral delivery systems with respect to their mechanisms and applications in the specific targeting of bone tissues or cells. Moreover, we discuss possible therapeutic agents that can be delivered against various bone related disorders. [ABSTRACT FROM AUTHOR]

In this paper, three kinds of polymer, of epoxy resin (EP), phenolic resin (PF), and unsaturated polyester (UP), were used as fillers to prepare the laminated composite surface, and the tribological properties of a composite surface were studied under dry sliding condition. The results showed that: (i) the composites surface without MoS2 exhibited high friction coefficient and high wear rate at 25 °C, while the friction coefficients were reduced when the temperature increases to 100 °C; (ii) with the addition of MoS2, the friction coefficient of the epoxy resin composite containing MoS2 (E1) was below 0.22 under a temperature of 25–150 °C, and the friction coefficient was increased to 0.32 as temperature increased to 150 °C, while the average friction coefficient of the unsaturated polyester composite containing MoS2 (U1) was very low and below 0.20 under a temperature of 25–150 °C. Analysis of the wear scars indicated that, for the MoS2-containing composite, the transfer films of the E1 and U1 were smooth and continuous under low temperature, while the transfer film of U1 was comparatively complete than that of E1 under 150 °C. The composites with solid lubrication had excellent high-temperature self-lubricating properties, which was attributed to the synergistic effect of the laminated structure, and the thermal expansion of the polymer, and finally a transfer film was formed on the sliding path. [ABSTRACT FROM AUTHOR]

Gene therapy is manipulation in/of gene expression in specific cells/tissue to treat diseases. This manipulation is carried out by introducing exogenous nucleic acids, such as DNA or RNA, into the cell. Because of their negative charge and considerable larger size, the delivery of these molecules, in general, should be mediated by gene vectors. Non-viral vectors, as promising delivery systems, have received considerable attention due to their low cytotoxicity and non-immunogenicity. As research continued, more and more functional non-viral vectors have emerged. They not only have the ability to deliver a gene into the cells but also have other functions, such as the performance of fluorescence imaging, which aids in monitoring their progress, targeted delivery, and biodegradation. Recently, many reviews related to non-viral vectors, such as polymers and cationic lipids, have been reported. However, there are few reviews regarding functional non-viral vectors. This review summarizes the common functional non-viral vectors developed in the last ten years and their potential applications in the future. The transfection efficiency and the transport mechanism of these materials were also discussed in detail. We hope that this review can help researchers design more new high-efficiency and low-toxicity multifunctional non-viral vectors, and further accelerate the progress of gene therapy.