Owing to its resistance to degradation, hair is an important bio‐sample with unique properties used to study post mortem decompositional changes. The present paper is a microscopical approach to ...preserved human scalp hair discovered at the 18th–19th‐century archaeological site of Iași, Romania. The hair fibre alterations were assessed using optical microscopy, scanning electron microscopy, image analysis and hair histological scores. External alterations showed a statistically significant heterogeneous degradation. Image analysis results of the internal degradation of hairs were correlated to external lesions. The results consider the implication of intrinsic biological factors in the post mortem degradation of human hair preserved in graves with comparable environmental conditions.
The heat shock (HS) response is an adaptation of organisms to elevated temperature. It includes substantial changes in the composition of cellular membranes, proteins and soluble carbohydrates. To ...protect the cellular macromolecules, thermophilic organisms have evolved mechanisms of persistent thermotolerance. Many of those mechanisms are common for thermotolerance and the HS response. However, it remains unknown whether thermophilic species respond to HS by further elevating concentrations of protective components. We investigated the composition of the soluble cytosol carbohydrates and membrane lipids of the thermophilic fungi Rhizomucor tauricus and Myceliophthora thermophilaat optimum temperature conditions (41-43 °С), and under HS (51-53 °С). At optimum temperatures, the membrane lipid composition was characterized by a high proportion of phosphatidic acids (PA) (20-35 % of the total), which were the main components of the membrane lipids, together with phosphatidylcholines (PC), phosphatidylethanolamines (PE) and sterols (St). In response to HS, the proportion of PA and St increased, and the amount of PC and PE decreased. No decrease in the degree of fatty acid desaturation in the major phospholipids under HS was detected. The mycelium of all fungi at optimum temperatures contained high levels of trehalose (8-10 %, w/w; 60-95 % of the total carbohydrates), which is a hallmark of thermophilia. In contrast to mesophilic fungi, heat exposure decreased the trehalose level and the fungi did not acquire thermotolerance to lethal HS, indicating that trehalose plays a key role in this process. This pattern of changes appears to be conserved in the studied filamentous thermophilic fungi.
Unsaturated fatty acids, such as oleic acid (OA) and linoleic acid (LA), are promising antimicrobial and cytostatic agents. We modified OA and LA with thymol (TOA and TLA, respectively) to expand ...their bioavailability, stability, and possible applications, and encapsulated these derivatives in polymeric nanoparticles (TOA-NPs and TLA-NPs, respectively). Prior to synthesis, we performed mathematical simulations with PASS and ADMETlab 2.0 to predict the biological activity and pharmacokinetics of TOA and TLA. TOA and TLA were synthesized via esterification in the presence of catalysts. Next, we formulated nanoparticles using the single-emulsion solvent evaporation technique. We applied dynamic light scattering, Uv-vis spectroscopy, release studies under gastrointestinal (pH 1.2-6.8) and blood environment simulation conditions (pH 7.4), and in vitro biological activity testing to characterize the nanoparticles. PASS revealed that TOA and TLA have antimicrobial and anticancer therapeutic potential. ADMETlab 2.0 provided a rationale for TOA and TLA encapsulation. The nanoparticles had an average size of 212-227 nm, with a high encapsulation efficiency (71-93%), and released TOA and TLA in a gradual and prolonged mode. TLA-NPs possessed higher antibacterial activity against
and
and pronounced cytotoxic activity against MCF-7, K562, and A549 cell lines compared to TOA-NPs. Our findings expand the biomedical application of fatty acids and provide a basis for further in vivo evaluation of designed derivatives and formulations.
In this paper we present the work related to the parameters identification for abrasive waterjet milling (AWJM) model that appears as an ill-posed inverse problem. The necessity of studying this ...problem comes from the industrial milling applications where the possibility to predict and model the final surface with high accuracy is one of the primary tasks in the absence of any knowledge of the model parameters that should be used. The adjoint approach based on corresponding Lagrangian gives the opportunity to find out the unknowns of the AWJM model and their optimal values that could be used to reproduce the required trench profile. Due to the complexity of the nonlinear problem and the large number of the model parameters, we use an automatic differentiation software tool. This approach also gives us the ability to distribute the research on more complex cases and consider different types of model errors and 3D time dependent model with variations of the jet feed speed. This approach gives us a good opportunity to identify the optimal model parameters and predict the surface profile both with self-generated data and measurements obtained from the real production. Considering different types of model errors allows us to receive the results acceptable in manufacturing and to expect the proper identification of unknowns.
Oscillometry is a popular technique for automatic estimation of blood pressure (BP). However, most of the oscillometric algorithms rely on empirical coefficients for systolic and diastolic pressure ...evaluation that may differ in various patient populations, rendering the technique unreliable. A promising complementary technique for automatic estimation of BP, based on the dependence of pulse transit time (PTT) on cuff pressure (CP) (PTT-CP mapping), has been proposed in the literature. However, a theoretical grounding for this technique and a nonparametric BP estimation approach are still missing. In this paper, we propose a novel coefficient-free BP estimation method based on PTT-CP dependence. PTT is mathematically modeled as a function of arterial lumen area under the cuff. It is then analytically shown that PTT-CP mappings computed from various points on the arterial pulses can be used to directly estimate systolic, diastolic, and mean arterial pressure without empirical coefficients. Analytical results are cross-validated with a pilot investigation on ten healthy subjects where 150 simultaneous electrocardiogram and oscillometric BP recordings are analyzed. The results are encouraging whereby the mean absolute errors of the proposed method in estimating systolic and diastolic pressures are 5.31 and 4.51 mmHg, respectively, relative to the Food and Drug Administration approved Omron monitor. Our work thus shows promise toward providing robust and objective BP estimation in a variety of patients and monitoring situations.
The accumulation of low molecular weight cytoprotective compounds (osmolytes) and changes in the membrane lipids composition are of key importance for the adaptation to stress impacts. However, the ...reason behind the wide variety of osmolytes present in the cell remains unclear. We suggest that specific functions of osmolytes can be revealed by studying the adaptation mechanisms of the mycelial fungus Emericellopsis alkalina (Hypocreales, Ascomycota) that is resistant to both alkaline pH values and high sodium chloride concentrations. It has been established that the fungus uses different osmolytes to adapt to ambient pH and NaCl concentration. Arabitol was predominant osmolyte in alkaline conditions, while mannitol prevailed in acidic conditions. On the salt-free medium mannitol was the main osmolyte; under optimal conditions (pH 10.2; 0.4 M NaCl) arabitol and mannitol were both predominant. Higher NaCl concentrations (1.0–1.5 M) resulted in the accumulation of low molecular weight polyol - erythritol, which amounted up to 12–14%, w/w. On the contrary, changes in the composition of membrane lipids were limited under pH and NaCl impacts; only higher NaCl concentrations led to the increase in the degree of unsaturation of membrane lipids. Results obtained indicated the key role of the osmolytes in the adaptation to the ambient pH and osmotic impacts.
To study the mechanisms of protection of the cell membranes and macromolecules from cold, the composition of osmolytes, membrane lipids, and their fatty acids in a submerged culture of
Mucor flavus
...was analyzed in growth dynamics at 20 and 4°C. This micromycete is psychrotolerant, having a wide growth temperature range (from –2 to 25°C) with an optimum at 20°C.
Mucor flavus
has a high growth rate (15 mm/day at 20°C, 4 mm/day at 0°C). At both temperatures, phosphatidic acids and phosphatidylethanolamines were predominant in the composition of membrane lipids, while phosphatidylcholines were the minor components. The main difference in the composition of membrane lipids was the threefold lower share of sterols at 4°C. During growth under optimal conditions, the proportion of phosphatidic acids decreased against the background of a slight increase in the levels of sterols, phosphatidylethanolamines, and phosphatidylcholines, while at 4°C the proportion of phosphatidic acids decreased slightly and the proportion of phosphatidylcholines increased. The fatty acids composition of phospholipids during growth at 20°C did not change significantly; linoleic, oleic, linolenic, and palmitic acids were predominant. At 4°C, the proportion of palmitic acid decreased and that of oleic acid increased, while the proportion of γ-linolenic acid decreased by half while that of α-linoleic acid increased. However, these changes did not lead to a significant change in the unsaturation degree of phospholipids, which varied between 1.5 and 1.6. Trehalose and glucose were the predominant osmolytes of the cytosol; glycerol was present in minor amounts only at 4°C. At both temperatures, the amount of osmolytes reached 3% of the dry weight in the course of growth, and the proportion of trehalose reached 70%. At both temperatures, a constant composition of osmolytes and slight changes in the composition of membrane lipids and their degree of unsaturation were observed, which probably contributes to the high growth rate of the fungus over a wide temperature range.
Principles of constructing theory of development and establishment of radiobiological reactions in the multilevel hierarchical structures of multicellular organisms are laid down on the bases of ...mathematical modeling and the theory of biosystems reliability. These principles are consistent with experimental and theoretical studies. Mathematical models were tested on the example of radiobiological effects of the perennial aquatic herbaceous plant Spirodela polyrrhiza. Possibility of using the proposed method for studying radiobiological and biophysical processes for biological structures of various complexity: from cell level to population level of higher plants is justified.
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