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Background/Objectives: One of the hallmarks of Alzheimer's disease (AD) is the accumulation of aggregated beta-amyloid (Aβ) protein in the form of senile plaques within brain tissue. Senile plaques contain various post-translational modifications of Aβ, including prevalent isomerization of Asp7 residue. The Asp7 isomer has been shown to exhibit increased neurotoxicity and induce amyloidogenesis in brain tissue of transgenic mice. The toxicity of Aβ peptides may be partly mediated by their structure and morphology. In this respect, in this study we analyzed the structural and aggregation characteristics of the Asp7 isoform of Aβ42 and compared them to those of synthetic Aβ42. We also investigated the effects of intracerebroventricular (i.c.v.) administration of these peptides, a method often used to induce AD-like symptoms in rodent models. Methods: Atomic force microscopy (AFM) was conducted to compare the morphological and aggregation properties of Aβ42 and Asp7 iso-Aβ42. The effects of i.c.v. stereotaxic administration of the proteins were assessed via behavioral analysis and reactive oxygen species (ROS) estimation in vivo using a scanning ion-conductance microscope with a confocal module. Results: AFM measurements revealed structural differences between the two peptides, most notably in their soluble toxic oligomeric forms. The i.c.v. administration of Asp7 iso-Aβ42 induced spatial memory deficits in rats and elevated oxidative stress levels in vivo, suggesting a potential of ROS in the pathogenic mechanism of the peptide. Conclusions: The findings support the further investigation of Asp7 iso-Aβ42 in translational research on AD and suggest its involvement in neurodegenerative processes. [ABSTRACT FROM AUTHOR]

Given the high growth rates of cognitive decline among the elderly population and the lack of effective etiological treatments, early diagnosis of cognitive impairment progression is an imperative task for modern science and medicine. It is of particular interest to identify predictors of an unfavorable subsequent course of cognitive disorders, specifically, rapid progression. Our study assessed the informative role of various risk factors on the dynamics of cognitive impairment among mild cognitive impairment (MCI) patients. The study included patients with MCI (N = 338) who underwent neuropsychological assessment, magnetic resonance imaging (MRI) examination, blood sampling for general and biochemical analysis, APOE genotyping, and polygenic risk score (PRS) evaluation. The APOE ε4/ε4 genotype was found to be associated with a diminished overall cognitive scores initial assessment and negative cognitive dynamics. No associations were found between cognitive changes and the PRS. The progression of cognitive impairment was associated with the width of the third ventricle and hematological parameters, specifically, hematocrit and erythrocyte levels. The absence of significant associations between the dynamics of cognitive decline and PRS over three years can be attributed to the provided suitable medical care for the prevention of cognitive impairment. Adding other risk factors and their inclusion in panels assessing the risk of progression of cognitive impairment should be considered. [ABSTRACT FROM AUTHOR]

Chemotherapy is among the main classical approaches to the treatment of oncologic diseases. Its efficiency has been comprehensively proven by clinical examinations; however, the low selectivity of chemotherapeutic agents limits the possibilities of this method, making it necessary to search for new approaches to the therapy of oncologic diseases. Photodynamic therapy is the least invasive method and a very efficient alternative for the treatment of malignant tumors; however, its efficiency depends on the depth of light penetration into the tissue and on the degree of oxygenation of the treatment zone. In this work, a hitherto unknown conjugate of a natural bacteriochlorin derivative and doxorubicin was obtained. In vitro and in vivo studies showed a more pronounced activity of the conjugate against MCF-7 and 4T1 cells and its higher tumorotropicity in animal tumor-bearing animals compared to free anthracycline antibiotic. The suggested conjugate implements the advantages of photodynamic therapy and chemotherapy and has great potential in cancer treatment. [ABSTRACT FROM AUTHOR]

The development of animal models of mental disorders is an important task since such models are useful for studying the neurobiological mechanisms of psychopathologies and for trial of new therapeutic drugs. One way to model pathologies of the nervous system is to impair fetal neurodevelopment through stress of the pregnant future mother, or prenatal stress (PS). The use of variable frequency ultrasound (US) in rodents is a promising method of imitating psychological stress, to which women in modern society are most often subjected. The aim of our study was to investigate the effect of PS induced by exposure to variable frequency ultrasound (US PS) throughout the gestational period on the adult rat offspring, namely, to identify features of behavioral alterations and neurochemical brain parameters that can be associated with certain mental disorders in humans, to determine the possibility of creating a new model of psychopathology. Our study included a study of some behavioral characteristics of male and female rats in the elevated plus maze, open-field test, object recognition test, social interaction test, sucrose preference test, latent inhibition test, Morris water maze, forced swimming test, acoustic startle reflex, and prepulse inhibition tests. We also determined the activity of the serotonergic, dopaminergic, and noradrenergic neurotransmitter systems in the hippocampus and frontal cortex by HPLC-ED. Concentration of norepinephrine, dopamine, DOPAC, serotonin, and HIAA, as well as DOPAC/dopamine and HIAA/serotonin ratios were determined. A correlation analysis of behavioral and neurochemical parameters in male and female rats was performed based on the data obtained. The results of the study showed that US PS altered the behavioral phenotype of the rat offspring. US PS increased the level of anxious behavior, impaired orientation-research behavior, increased grooming activity, decreased the desire for social contacts, shifted behavioral reactions from social interaction to interaction with inanimate objects, impaired latent inhibition, and decreased the startle reflex. US PS activated the serotonergic, dopaminergic, and noradrenergic neurotransmitter systems of the rat frontal cortex and hippocampus. A correlation between neurochemical and behavioral parameters was revealed. Our study showed that US PS leads to a certain dysfunction on behavioral and neurochemical levels in rats that is most closely associated with symptoms of schizophrenia or autism. We hypothesize that this could potentially be an indicator of face validity for a model of psychopathology based on neurodevelopmental impairment. [ABSTRACT FROM AUTHOR]

The article presents the authors’ methodology for studying technical ignition causes of cars, with the establishment of the initial fire based on the signs and nature of temperature damage. What is more, subsequent development of the main scenario of fire occurrence is introduced. Modern control system is becoming larger and more complicated day by day and probability of system outage increases with it, so people urgently need to personalize the system of failure diagnostics to conduct real-time monitoring and malfunction diagnosis in production system and take necessary steps to improve its overall reliability and maintainability. According to the presented method of fire research, determination of the ignition causes is carried out by the method of successive elimination. Based on the functional features of the researchable object (a motor vehicle), established by expertise as an initial fire, the ignition of flammable liquid because of leakage from the fuel system, thermal development of the processes accompanying the emergency operation mode of the power grid could be possible ignition causes of the car. The authors pay special attention to the fire hazard of the electric system of a vehicle, which is determined by the fact that its individual elements can serve as a source of burning in case of an emergency in some functional chain. Establishment of initial fire causes increased complexity in connection with relatively small size of cars (especially light cars), fleetness of fires in vehicles and in case of failure to take recovery measures for burning in the initial stage and its development for the entire volume of the car. The results of applying the methodology were positively evaluated by independent expert companies.

Danger is a key concept of life safety it is, constantly being transforming and taking on new forms at the present time. Information and information technologies play an important role in the modern world, which causes the need for further research in this area, including to ensure the safety of various aspects of life. In modern research, it is presented that information flows are characterized by an information, energy component. Theodore van Houen, the creator of the theory of quantum entropy logic, showed in his theory that information flows have material properties, information is a material form of matter. The development of energy information technologies or methods of nonlinear forecasting, which is based on quantum entropy logic, currently opens up unlimited possibilities for obtaining information. These technologies are widely used in foreign countries for various purposes: for medical purposes for diagnosing diseases, as well as for the study of events in time and space. These technologies are being actively developed in our country in private laboratories and institutes and are used for preventive analysis in order to prevent unfavorably developing events.

Advantages of light-optical devices (LEDs) were investigated in the article. Based on the research, special attention is paid to the prospects of development of led headlights. Complicacy of car electrical equipment leads to increase of indicated efficiency and energy storage capacity and electric generators, yield increase, decrease of labor intensity maintenance operation and reconstruction. On the other hand, innovations in scientific-technological progress in electronic engineering sphere lead to rise in reluctances, so more than 30% of these reluctances account for electrical equipment. Analysis of current requirements to automobile components of lighting devices has been carried out. LEDs as automobile light sources are gaining rapid popularity. Currently, LEDs are widely used as internal light sources (instrument illumination, indicator lamps) and external ones (tail lights, additional brake lights, daytime running lights). Since 2007, white LEDs have been used as dipped- and main-beam sources. Light sources are characterized by such parameters as voltage, light power and luminous power. Derivative of these parameters is the luminous efficiency (luminous power per unit of light power), that acts as a kind of lamp’s performance and economy indicator. This article has been made in relation to the study of auto technical expertise in Moscow and Moscow Region.