Enrichment of the habitat of captive rodents Heterocephalus glaber (naked mole rats) to implement their innate behavioral pattern of digging dense soil in search of food, paradoxically led to the appearance of unusual animals in the colony. They showed signs of cachexia, distinguished from other animals by a lower temperature (from 31 degrees C to 26 degrees C) and body mass index with decreasing proportion of subcutaneous fat. This animal demonstrated aggressive feeding behavior, but didn't gain weight even after finishing experiment with intensive physical activity. In histochemical analysis of tissues from cachexic and normal animals of the same age and sex liver hyperlipofuscinos is was revealed and indicated that animals when being in a habitat with an increased oxygen content for them (21 % versus 8 % in their natural underground habitat), experienced severe oxidative stress during physical exercise. Stress led to a disruption of the body's regulatory systems, a sharp increase in metabolism even at rest, an overload of the cardiovascular and respiratory systems and damage to organs and tissues. To clarify the pathogenetic mechanism of the observed phenomenon, microRNA was extracted from the animal tissues and sequenced. Then bioinformatics analysis of differential expression of microRNAs between groups of healthy animals and animals with idiopathic cachexia was performed. (c) 2025 Elsevier B.V. and Soci & eacute;t & eacute; Fran & ccedil;aise de Biochimie et Biologie Mol & eacute;culaire (SFBBM). All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Enrichment of habitat of the captive rodents Heterocephalus glaber (naked mole rats) allowing them to implement the innate behavioral pattern of digging through hard soil somehow led to the emergence of unusual animals showing signs of cachexia in the colony; these differed from other animals by the reduced body mass index associated with subcutaneous fat reduction. Furthermore, the animals itself showed aggressive eating behavior, but showed no weight gain even after stopping digging due to detachment of the camera with soil. The study aimed to clarify the pathogenetic mechanism underlying the reported phenomenon. For that animals showing signs of cachexia (one female and two males aged 4-5 years) were withdrawn from the colony, along with the animals showing no such signs (two females and one male aged 4-5 years) as controls. Histologic assessment of tissues revealed cardiac hypertrophy and hyperlipofuscinosis of the liver. Cardiac hypertrophy was also suggested by the results of the animal heart microRNA sequencing bioinformatics analysis that revealed elevated levels of microRNA responsible for the increased cell division activity and reduced apoptotic activity in the heart. These data suggest that the animals living in the habitat with the increased oxygen content (21% vs. 8% in the natural habitat, underground) experienced severe oxidative stress during physical activity, which resulted in dysfunction of body's regulatory systems, increased metabolism at rest, cardiovascular system overload, and damage to organs and tissues. Thus, naked mole rats can have normal physical activity only under conditions of low oxygen content.

Cairo is one of the largest megacities in the World and the particle load of its atmosphere is known to be particularly important. In this work we aim at assessing the temporal variability of the aerosol's characteristics and the magnitude of its impacts on the transfer of solar radiation. For this we use the level 2 quality assured products obtained by inversion of the instantaneous AERONET sunphotometer measurements performed in Cairo during the Cairo Aerosol CHaracterization Experiment (CACHE), which lasted from the end of October 2004 to the end of March 2006. The analysis of the temporal variation of the aerosol's optical depth (AOD) and spectral dependence suggests that the aerosol is generally a mixture of at least 3 main components differing in composition and size. This is confirmed by the detailed analysis of the monthly-averaged size distributions and associated optical properties (single scattering albedo and asymmetry parameter). The components of the aerosol are found to be 1) a highly absorbing background aerosol produced by daily activities (traffic, industry), 2) an additional, 'pollution' component produced by the burning of agricultural wastes in the Nile delta, and 3) a coarse desert dust component. In July, an enhancement of the accumulation mode is observed due to the atmospheric stability favoring its building up and possibly to secondary aerosols being produced by active photochemistry. More generally, the time variability of the aerosol's characteristics is due to the combined effects of meteorological factors and seasonal production processes. Because of the large values of the AOD achieved during the desert dust and biomass burning episodes, the instantaneous aerosol radiative forcing (RF) at both the top (TOA) and bottom (BOA) of the atmosphere is maximal during these events. For instance, during the desert dust storm of April 8, 2005 RFBOA. RFTOA, and the corresponding atmospheric heating rate peaked at -161.7W/m(2), -65.8 W/m(2), and 4.0 K/d, respectively. Outside these extreme events, the distributions of the radiative forcing values at BOA and TOA are Gaussian with means and standard deviations of 58 (27), and 19(11)W/m(2), respectively. These two negative values indicate a cooling effect at the 2 atmospheric levels but the largest absolute value at BOA corresponds to a trapping of solar radiation inside the atmosphere. The averages of the instantaneous forcing efficiencies (FE) derived from measurements performed at solar zenith angles between 50 and 76 are 195 (+/-42) and -62(+/-17)W/m(2).AOD(550) for BOA and TOA, respectively. The value at TOA is larger than in other urban environments, which could be due to the desert dust component backscattering more solar radiation to space than absorbing urban aerosols. The lower absorption of solar light by desert dust also explains qualitatively the lower than usual value of FEBOA. A more precise study of the effects of the desert dust and biomass burning aerosols shows that fluctuations of their monthly-averaged concentrations explain the departures of the TOA and BOA radiative forcings from the background situation. In April, the contributions of DD to the month averages of the instantaneous radiative forcing are as high as 53% at BOA, and 66% at TOA. In October, the biomass burning mode contributes 33 and 27% of these forcings, respectively. Noteworthy is that the contribution of DD to RF is never less than 17% (at BOA) and 27% (at TA), emphasizing the importance of the mineral dust component on the transfer of solar radiation above Cairo, and this even in months when no major dust storm is observed. (C) 2010 Elsevier B.V. All rights reserved.