Origin and Development of the Adipose Tissue, a Key Organ in Physiology and Disease

Adipose tissue is a dynamic organ, well known for its function in energy storage and mobilization according to nutrient availability and body needs, in charge of keeping the energetic balance of the organism. During the last decades, adipose tissue has emerged as the largest endocrine organ in the human body, being able to secrete hormones as well as inflammatory molecules and having an important impact in multiple processes such as adipogenesis, metabolism and chronic inflammation. However, the cellular progenitors, development, homeostasis and metabolism of the different types of adipose tissue are not fully known. During the last decade, Drosophila melanogaster has demonstrated to be an excellent model to tackle some of the open questions in the field of metabolism and development of endocrine/metabolic organs. Discoveries ranged from new hormones regulating obesity to subcellular mechanisms that regulate lipogenesis and lipolysis. Here, we review the available evidences on the development, types and functions of adipose tissue in Drosophila and identify some gaps for future research. This may help to understand the cellular and molecular mechanism underlying the pathophysiology of this fascinating key tissue, contributing to establish this organ as a therapeutic target.

Greenhouse Effect in the Standard Atmosphere

The “line-by-line” method is used for the evaluation of thermal emission of the standard atmosphere toward the Earth. Accounting for thermodynamic equilibrium of the radiation field with air molecules and considering the atmosphere as a weakly nonuniform layer, we reduce the emission at a given frequency for this layer containing molecules of various types to that of a uniform layer, which is characterized by a certain radiative temperature Tω, an optical thickness uω and an opaque factor g(uω). Radiative parameters of molecules are taken from the HITRAN database, and an altitude of cloud location is taken from the energetic balance of the Earth. Within the framework of this model, we calculate the parameters of the greenhouse effect, including the partial radiative fluxes due to different greenhouse components in the frequency range up to 2600 cm−1. In addition, the derivations are determined from the radiative flux from the atmosphere to the Earth over the concentration logarithm of greenhouse components. From this, it follows that the observed rate of growth of the amount of atmospheric carbon dioxide accounts for a contribution of approximately 30% to the observed increase in the global atmosphere during recent decades. If we assume that the basic part of the greenhouse effect is determined by an increase in the concentration c(H2O) of water atmospheric molecules, it is approximately dlnc(H2O/dt)=0.003 yr−1. This corresponds to an increase in the average moisture of the atmosphere of 0.2%/yr.

Pituitary and ovarian hormones: is their plasma concentration affected by litter size in primiparous lactating rabbit does?

Genetic selection in commercial rabbit lines based on litter size has positively improved the number of kits suckling, presumably to weaning. Although it has been proven that the energetic balance of primiparous does is due to the need to satisfy pregnancy, lactation and growth requirements, litter size adjustment from 7 to 12 kits is applied as a routine in commercial rabbit farms. The suckling stimulus provokes a prolactin (PRL) secretion, which in turn can modulate the preovulatory release of luteinising hormone (LH) and, consequently, the ovulatory and productive responses of the does. This study aimed to determine if litter size of prolific primiparous rabbit does during lactation [Group HL, with high litter density (10-12 kits; n=21) and Group LL, with low litter density (7-9 kits; n=29)] influences plasma concentration of PRL. Blood samples from lactating does were taken weekly throughout lactation starting on day 4 post-partum, until day 32 post-partum, before and immediately after suckling. In addition, the does were re-inseminated after weaning (day 32 post-partum), and sampled at 0 and 60 min after induction of ovulation to determine whether litter size affected the peak of LH, progesterone (P4) concentrations and the main productive parameters of their second pregnancy. All hormones were determined by enzyme immunoassay. Statistical analysis of the results revealed that the PRL concentrations of hyperprolific rabbit does before and immediately after a suckling stimulus from 7-9 or 10-12 kits were significanltly different, as we only detected basal levels, with a rise after weaning in both groups. More studies are necessary, delaying blood sampling to later periods of time after the suckling stimulus, in order to conclude whether the peak release of this hormone is altered or not. There were also no differences in plasma LH and progesterone levels after artificial insemination, or in productive performance of these females after their second pregnancy. In conclusion, the litter size adjustment of prolific primiparous rabbits with 7 to 12 kits determines adequate pituitary, ovarian and reproductive responses at second parturition if the does are inseminated after weaning.

Comparative Analysis of Right Ventricle Fluid Dynamics

The right and left sides of the human heart operate with a common timing and pump the same amount of blood. Therefore, the right ventricle (RV) presents a function that is comparable to the left ventricle (LV) in terms of flow generation; nevertheless, the RV operates against a much lower arterial pressure (afterload) and requires a lower muscular strength. This study compares the fluid dynamics of the normal right and left ventricles to better understand the role of the RV streamlined geometry and provide some physics-based ground for the construction of clinical indicators for the right side. The analysis is performed by image-based direct numerical simulation, using the immersed boundary technique including the simplified models of tricuspid and mitral valves. Results demonstrated that the vortex formation process during early diastole is similar in the two ventricles, then the RV vorticity rapidly dissipates in the subvalvular region while the LV sustains a weak circulatory pattern at the center of the chamber. Afterwards, during the systolic contraction, the RV geometry allows an efficient transfer of mechanical work to the propelled blood; differently from the LV, this work is non-negligible in the global energetic balance. The varying behavior of the RV, from reservoir to conduct, during the different phases of the heartbeat is briefly discussed in conjunction to the development of possible dysfunctions.

Van der Waals interaction affects wrinkle formation in two-dimensional materials

Nonlinear mechanics of solids is an exciting field that encompasses both beautiful mathematics, such as the emergence of instabilities and the formation of complex patterns, as well as multiple applications. Two-dimensional crystals and van der Waals (vdW) heterostructures allow revisiting this field on the atomic level, allowing much finer control over the parameters and offering atomistic interpretation of experimental observations. In this work, we consider the formation of instabilities consisting of radially oriented wrinkles around mono- and few-layer “bubbles” in two-dimensional vdW heterostructures. Interestingly, the shape and wavelength of the wrinkles depend not only on the thickness of the two-dimensional crystal forming the bubble, but also on the atomistic structure of the interface between the bubble and the substrate, which can be controlled by their relative orientation. We argue that the periodic nature of these patterns emanates from an energetic balance between the resistance of the top membrane to bending, which favors large wavelength of wrinkles, and the membrane-substrate vdW attraction, which favors small wrinkle amplitude. Employing the classical “Winkler foundation” model of elasticity theory, we show that the number of radial wrinkles conveys a valuable relationship between the bending rigidity of the top membrane and the strength of the vdW interaction. Armed with this relationship, we use our data to demonstrate a nontrivial dependence of the bending rigidity on the number of layers in the top membrane, which shows two different regimes driven by slippage between the layers, and a high sensitivity of the vdW force to the alignment between the substrate and the membrane.

Effects of Late-Life Caloric Restriction on Age-Related Alterations in the Rat Cortex and Hippocampus

Background: A major problem of aging is the disruption of metabolic homeostasis. This is particularly relevant in the brain where it provokes neurodegeneration. Caloric restriction is a physiologic intervention known to delay the deleterious consequences of aging in several species ranging from yeast to mammals. To date, most studies on experimental models have started this dietary intervention from weaning, which is very difficult to be translated to human beings. Here, we study the effects of a more realistic dietary regimen in rats, starting at an advanced age and lasting for six months. Methods: we analyzed in the cortex and hippocampus, the proteins involved in the energetic balance of the cells, cholesterol metabolism, oxidative stress response, inflammation, synaptic impairment, and brain trophism. Results: our results suggest that caloric restriction in late life can revert only some age-related changes studied here.

Energetic Balance of Biogas and Fertilizing Potential of Digestate from Anaerobic Digestion of Manihot Utilissima

Optimal scale production of biogas from the anaerobic digestion (AD) of organic wastes (OWs) as substrates has become one of stimulating environment-friendly procedures to foster the replacement of fossil energies by renewable ones. AD of OWs generated from households is desirable as an effective method to fight against environmental pollution effects of the latter in developing countries. Notably in Africa where each year there are more than 600,000 premature deaths following the use of solid biomass energy (especially charcoal). Yet, if assessing the potential of biogas production, that is, biochemical methane potential (BMP) has played a prominent role in the choice of substrates, in the other hand the evaluation of the optimal ratio between the quantity of variety OWs and the amount of energy to be produced has not received several attentions. The latter is valuable not only for energetic productivity but also for profitability. Thus, in this report, an energetic balance between the amount of leaves and stems of Manihot Utilissima (MU) annually produced as well as the energetic potential of their biogas were investigated. Cow manure (CM) was employed as inoculum, under mesophilic conditions of the collection sites: Ngaba and Ndjili in Kinshasa City Province (KCP), Congo DR, where the leaves and stems of MU are among the most generated wastes. Furthermore, we evaluated the fertilizing potential of digestates from the AD of the leaves and stems by their Carbon/Nitrogen (C/N) ratios. The annual energetic potentials of biogas produced were estimated to be 1.362 ± 0.028 109 kWh for the leaves and 0.337 ± 0.006 109 kWh for the stems. These were associated to the energy needs for the KCP households corresponding to the use of charcoal. The latter was evaluated to be 166 103 tons for leaves and 41 103 tons for the stems of MU, respectively. The fertilizing potential of digestates from the AD of the leaves and stems of MU assessed by their C/N ratios were determined to be 5 and 10, respectively; indicating that they are favorable for the cultivation of vegetables and fruit trees in KCP soils (C/N~5) but also optimal for the organisms, soil conditioning and could improve the soils hydraulic conductivity (C/N~10).

„Meat Should Be Prescribed in Very Small Doses, Arsenic-like”. How Josephine Joteyko and Varia Kipiani Pioneered Medical Research to Improve Vegetarianism in 1906

This compilation is based on the original report on a clinical survey conducted in Brussels (1905-1906) by Josephine Joteyko and Varia Kipiani with 43 vegetarians. Having advanced expertise in physiology and experimentalism, Joteyko (with Lithuanian and Polish origins) and Kipiani (with Georgian origins) discussed their findings at the Congress of the Belgian Society for Vegetarianism in 1906. For both children and adults, females and males, regardless of age, the findings demonstrated vegetarian dietary habits to be beneficiary for human development, the subjects’ physical and mental health, welfare, and physical and intellectual efficiency. Surprisingly, Joteyko and Kipiani confirmed C. Darwin’s observation across various nutritional cultures that vegetarian food would increase the energetic balance of the human body. Additionally, their focus on the moteur humain shows affinities with Taylorism, the modernist utopias of labor, the enhancement of human faculties, the protection of workers and their rights from automation, and applied social science represented by Joteyko and Kipiani as multidisciplinary investigators. The compilation was made on: J. Joteyko & V. Kipiani, Enquête scientifique sur les Végétariens de Bruxelles, Conférence donnée à la Société végétarienne de Belgique, le 4 décembre 1906, pp. 1–77, with no further correction.

Numerical simulation and analysis of pressure distribution and airflow speed around an airborne cloud microphysics measurements instrument

Clouds have an important impact on Earth’s energetic balance, so measuring accurately the microphysical parameters and using them in research has become one important step in atmospheric studies. Regarding the fact that light scattering probes convert the flow rate to concentration, any wrong assumption or measurement of the flow rate can lead to incorrect results. Applying numerical simulation to an airborne cloud microphysics measurements instrument can provide information that can be measured in any point of the sampling volume, and further used in determination of microphysics parameters, providing more accurate data. Taking this into consideration, in this paper are presented the results of numerical simulation applied to Cloud Aerosol and Precipitation Spectrometer and the comparison with results reported in literature.

Amino Acid and Carbohydrate Metabolism Are Coordinated to Maintain Energetic Balance during Drought in Sugarcane

The ability to expand crop plantations without irrigation is a major goal to increase agriculture sustainability. To achieve this end, we need to understand the mechanisms that govern plant growth responses under drought conditions. In this study, we combined physiological, transcriptomic, and genomic data to provide a comprehensive picture of drought and recovery responses in the leaves and roots of sugarcane. Transcriptomic profiling using oligoarrays and RNA-seq identified 2898 (out of 21,902) and 46,062 (out of 373,869) transcripts as differentially expressed, respectively. Co-expression analysis revealed modules enriched in photosynthesis, small molecule metabolism, alpha-amino acid metabolism, trehalose biosynthesis, serine family amino acid metabolism, and carbohydrate transport. Together, our findings reveal that carbohydrate metabolism is coordinated with the degradation of amino acids to provide carbon skeletons to the tricarboxylic acid cycle. This coordination may help to maintain energetic balance during drought stress adaptation, facilitating recovery after the stress is alleviated. Our results shed light on candidate regulatory elements and pave the way to biotechnology strategies towards the development of drought-tolerant sugarcane plants.