The Biomechanics of the Locust Ovipositor Valves: a Unique Digging Apparatus

The female locust has a unique mechanism for digging in order to deposit its eggs deep in the ground. It utilizes two pairs of sclerotized valves to displace the granular matter, while extending its abdomen as it propagates underground. This ensures optimal conditions for the eggs to incubate, and provides them with protection from predators. Here, two major axes of operation of the digging valves are identified, one in parallel to the propagation direction of the ovipositor, and one perpendicular to it. The direction-dependent biomechanics of the locust major, dorsal digging valves are quantified and analyzed, under forces in the physiological range and beyond, considering hydration level, as well as the females age, or sexual maturation state. Our findings reveal that the responses of the valves to compression forces in the specific directions change upon sexual maturation to follow their function, and depend on environmental conditions. Namely, in the physiological force range, the valves are resistant to mechanical failure. In addition, mature females, which lay eggs, have stiffer valves, up to roughly nineteen times the stiffness of the pre-mature locusts. The valves are stiffer in the major working direction, corresponding to soil shuffling and compression, compared to the direction of propagation. Hydration of the valves reduces their stiffness but increases their resilience against failure. These findings provide mechanical and materials guidelines for the design of novel non-drilling excavating tools, including 3D-printed anisotropic materials based on composites.

MicroRNA-155 Expression With Brucella Infection in vitro and in vivo and Decreased Serum Levels of MicroRNA-155 in Patients With Brucellosis

Infection by Brucella is characterized by the inhibition of host immune responses. MicroRNA-155 (miR-155) has been implicated in the immune response to many diseases. In this study, miR-155 expression during Brucella 16M infection of macrophages and mice were analyzed. Expression of miR-155 was significantly induced in macrophages at 24 hours post infection. Analysis of infected mice showed that miR-155 was inhibited at 7 and 14 days, but induced at 28 days. Very interestingly, the induction or inhibition trend was reversed at 7 and 14 days in 16M△virB-infected mice. This suggested that decreased expression of miR-155 at an early stage of infection was dependent on intracellular replication. In humans with brucellosis, serum levels of miR-155 were significantly decreased compared to those without brucellosis and healthy volunteers. Significant correlations were observed between serum level of miR-155 and serum anti-Brucella antibody titers and symptom of sweat. The decrease in miR-155 with Brucella infection contrasts with the increase in miR-155 observed in Mycobacterium tuberculosis infection. This contrasting effect suggests that Brucella interferes with miR-155-regulated immune responses through a unique mechanism. Taken together, data from this study indicate that Brucella infection affects miR-155 expression, and that human brucellosis patients show decreased serum levels of miR-155.

The TPLATE complex mediates membrane bending during plant clathrin–mediated endocytosis

Clathrin-mediated endocytosis is the major route of entry of cargos into cells and thus underpins many physiological processes. During endocytosis, an area of flat membrane is remodeled by proteins to create a spherical vesicle against intracellular forces. The protein machinery which mediates this membrane bending in plants is unknown. However, it is known that plant endocytosis is actin independent, thus indicating that plants utilize a unique mechanism to mediate membrane bending against high-turgor pressure compared to other model systems. Here, we investigate the TPLATE complex, a plant-specific endocytosis protein complex. It has been thought to function as a classical adaptor functioning underneath the clathrin coat. However, by using biochemical and advanced live microscopy approaches, we found that TPLATE is peripherally associated with clathrin-coated vesicles and localizes at the rim of endocytosis events. As this localization is more fitting to the protein machinery involved in membrane bending during endocytosis, we examined cells in which the TPLATE complex was disrupted and found that the clathrin structures present as flat patches. This suggests a requirement of the TPLATE complex for membrane bending during plant clathrin–mediated endocytosis. Next, we used in vitro biophysical assays to confirm that the TPLATE complex possesses protein domains with intrinsic membrane remodeling activity. These results redefine the role of the TPLATE complex and implicate it as a key component of the evolutionarily distinct plant endocytosis mechanism, which mediates endocytic membrane bending against the high-turgor pressure in plant cells.

A co-opted endogenous retroviral envelope promotes cell survival by controlling SLC31A1/CTR1-mediated copper transport and homeostasis

Copper is a critical element for eukaryotic life, involved in numerous cellular functions and in redox balance but it can be toxic in excess. Therefore, tight regulation of copper acquisition and homeostasis is essential for cell physiology and survival. Here, we identified a unique mechanism for cell survival involving the regulation of copper homeostasis by an endogenous retroviral (ERV) envelope glycoprotein called Refrex1. We show that extracellular copper sensing by cells increased Refrex1 expression, which in turn regulated copper acquisition through interaction with the main copper transporter SLC31A1/CTR1. Downmodulation of Refrex1 resulted in intracellular copper accumulation leading to ROS production and subsequent apoptosis, which could be reverted by copper chelator treatment. Our results demonstrate that Refrex1 has been co-opted for its ability to regulate copper entry through CTR1 interaction in order to limit copper excess for a proper redox balance, and suggests that other ERV may have similar metabolic functions among vertebrates.

Motherhood and cultural and historical traditions

The problem of the relationship and interaction of motherhood with the development of culture became very serious and very significant. It requires consistent scientific research and philosophical generalization. The article presents a holistic vision of the phenomenon of motherhood in the context of culture. The motherhood considered from these positions acts as the specific phenomenon of our existence, the unique mechanism of physical and sociocultural reproduction of the person. In a sense, motherhood can be seen as a center that forms culture, because initially the cultural space for the child is concentered around the mother.

Roles of host mitochondria in the development of COVID-19 pathology: Could mitochondria be a potential therapeutic target?

The recent emergence of severe acute respiratory syndrome-Corona Virus 2 (SARS-CoV-2) in late 2019 and its spread worldwide caused an acute pandemic of Coronavirus disease 19 (COVID-19). Since then, COVID-19 has been under intense scrutiny as its outbreak led to significant changes in healthcare, social activities, and economic settings worldwide. Although angiotensin-converting enzyme-2 (ACE-2) receptor is shown to be the primary port of SARS-CoV-2 entry in cells, the mechanisms behind the establishment and pathologies of COVID-19 are poorly understood. As recent studies have shown that host mitochondria play an essential role in virus-mediated innate immune response, pathologies, and infection, in this review, we will discuss in detail the entry and progression of SARS-CoV-2 and how mitochondria could play roles in COVID-19 disease. We will also review the potential interactions between SARS-CoV-2 and mitochondria and discuss possible treatments, including whether mitochondria as a potential therapeutic target in COVID-19. Understanding SARS-CoV-2 and mitochondrial interactions mediated virus establishment, inflammation, and other consequences may provide a unique mechanism and conceptual advancement in finding a novel treatment for COVID-19.

Traumatic Avulsion Fracture of the Origin of the Brachioradialis Muscle: A Case Report and Review of the Literature

Avulsion fracture of the brachioradialis muscle origin at the proximal two-thirds of the lateral supraepicondylar ridge of the humerus is an extremely rare fracture with only 4 reported cases in the literature so far. In this article, we describe the case of a 50-year-old male patient who had sustained a closed fracture of the latter after falling from a height of 1.5 m on a flexed elbow and pronated hand. The patient was managed with immobilization of the elbow and wrist with a posterior splint in neutral position for 3 weeks, followed by wrist and elbow therapeutic mobilization sessions for 3 months. At the final follow-up, the patient had painless active and passive full range of motion of the elbow along with good flexion strength. The unique mechanism by which this avulsion fracture occurred is explained on the basis of the mode of injury, position of the limb, and structure and function of the brachioradialis muscle.

1-Formyl-β-carboline Derivatives Block Newcastle Disease Virus Proliferation through Suppressing Viral Adsorption and Entry Processes

Newcastle disease virus (NDV) is one of the highly contagious pathogens causing devastating economic effects on the global poultry industry. In the present study, three 1-formyl-β-carboline derivatives (compounds 6, 7, and 9) were found to be potent inhibitors of different genotypes of NDV with IC50 values within 10 μM, which are similar to ribavirin. The virus titers were decreased by the presence of 1-formyl-β-carboline derivatives in a dose-dependent manner, and the inhibition rate was found to exceed 90% at the concentration of 20 μM. These compounds mainly suppressed the adsorption and entry processes of NDV lifecycle. Through DARTS, CETSA, and RBC binding assay, these compounds were identified as novel HN inhibitors, which could directly interact with the NDV HN protein to affect the adsorption of NDV. Furthermore, they could inhibit the entry of NDV through suppressing the PI3K/Akt pathway rather than the ERK pathway. The PI3K/Akt pathway was proved to be involved in NDV entry. Our findings reveal a unique mechanism through which 1-formyl-β-carboline derivatives restrain NDV infection. Moreover, these compounds represent suitable scaffolds for designing novel HN inhibitors.

LEGAL MEASURES OF THE STATE PREVENTION OF ETHNIC AND RELIGIOUS CONFLICTS

The article studies the ethnic and religious conflicts developed over the last years. The author comes to the conclusion that many disputable events of the geopolitical process and the administrative law forms of state activity are the main reasons for all these conflicts. This article finds the ways to solve eth- nic and religious conflicts, as well as it reviews modern means of preventing them. However a wide range of mechanisms to settle this problem isn’t able to resolve it. In this context the author tries to make a unique mechanism suitable for settlement or prevention of all conflicts, or at least the major part of them.