The design of immobilized enzyme preparations is an important and relevant area of modern sciences and technologies. Immobilization of enzymes from animal sources (component I) on natural carriers ...(component II) increases the system stability by protecting the active site of the enzyme from deactivation; facilitates the separation and accelerates the recovery of the enzyme. This makes reuse possible and provides a significant reduction in operating costs. Hydrolytic enzymes (such as lipases) and polysaccharides (such as chitosan) are the most promising of such pairs of components. The main attention here is devoted to the discussion on lipase immobilization on polysaccharide (mainly - chitin and chitosan). Based on the analysis of the available literature, the most adequate method is the immobilization of lipase from porcine pancreas (LPP) on polysaccharide particles (such as chitin or chitosan) pre-treated with ultrasound (to increase the particle surface area) and glutaraldehyde (for particle activation) that shows reasonably high LPP activity and stability. In order to increase further the activity of the lipase, some authors proposed to incorporate a spacer in the form of 1,3-diaminopropane (or 1,3-diaminobutane) prior to activation of the surface of the chitosan particles. In particular cases, the use of chitin (instead of chitosan) may be an alternative solution for biotechnological applications.
Recently the idea of constructing “supramolecular enzyme systems” realized in the so-called “coimmobilized multienzymatic systems” strategy. The most fascinating example is the combined assay of a mixture of native LPP, glycerol kinase (from Cellulomonas) and glycerol-3-phosphate oxidase (from Aerococcus viridans) linked by glutaraldehyde to chitosan (as shell for inorganic nanoparticle core). This material was placed on a Pt-electrode as biosensor and was successfully applied for amperometric determination of the triglyceride level in the serum of healthy and diseased person. Thus, the whole innovative research-production sequence is described by Aggarwal V. and Pundir C.S.: from simple components to advanced material and further biomedical application.
Thus, the following approach of lipase immobilization appears the most promising for future applications: a few types of lipases or the combination of LPP with some other enzymes immobilized simultaneously on multifunctional carriers (as nanohybrids of inorganic core and polysaccharide shell).
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•Immobilization of enzymes on natural carriers is an important area of biocolloids.•Lipase immobilized on chitosan particles (ChiPs) is useful for bionanotechnology.•Lipase adsorption on ChiPs (using ultrasound) increases the activity and stability.•Lipase linked to ChiPs (by glutaraldehyde) is useful for particle activation.
RNA polymerase II (POL II) is responsible for the transcription of messenger RNAs (mRNAs) and long non-coding RNAs (lncRNAs). Previously, we have shown the evolutionary invariance of the structural ...features of DNA in the POL II core promoters of the precursors of mRNAs. In this work, we have analyzed the POL II core promoters of the precursors of lncRNAs in
and
genomes. Structural analysis of nucleotide sequences in positions -50, +30 bp in relation to the TSS have shown the extremely heterogeneous 3D structure that includes two singular regions - hexanucleotide "INR" around the TSS and octanucleotide "TATA-box" at around ~-28 bp upstream. Thus, the 3D structure of core promoters of lncRNA resembles the architecture of the core promoters of mRNAs; however, textual analysis revealed differences between promoters of lncRNAs and promoters of mRNAs, which lies in their textual characteristics; namely, the informational entropy at each position of the nucleotide text of lncRNA core promoters (by the exception of singular regions) is significantly higher than that of the mRNA core promoters. Another distinguishing feature of lncRNA is the extremely rare occurrence in the TATA box of octanucleotides with the consensus sequence. These textual differences can significantly affect the efficiency of the transcription of lncRNAs.
Goats are ubiquitous, including in hot and dry regions, while also being very sensitive to climate fluctuations, expressed in temperature differences. This affects their productivity and milk ...quality. Adaptation to heat requires high energy costs, affects "neurohumoral" regulation and is accompanied by oxidative stress with the increased production of free radicals. The aim was to study the main biochemical parameters of goat milk and its antioxidant activity depending on the season of the year. Sampling was carried out in April, June, August and October. Analysis of the biochemical components and antioxidant activity of goat milk was performed using modern analytical systems. From spring to autumn, the mass fraction of true or crude proteins in goat milk increased by 14.6-63.7% or by 12.3-52.1%, and the mass fraction of caseins also increased by 13.6-60.6%. For vitamin C level and the total amount of water-soluble antioxidants, a pronounced gradual decrease from spring to autumn was observed. In the summer period, a small increase in the carotene level in milk (by 3.0-6.1% compared to April) was established. Vitamin A content increased by 86.5% (June) or by 70.3% (October) compared to April. Thus, the numerous significant changes in the major parameters of goat's milk depending on the season were revealed.
The effects of chitosan as feed additive for animals (FAFAs) on various digestive processes are an important to study because of the animal nutrition and production quality, healthcare and farming. ...The aims of this study were to evaluate the total amount of water-soluble antioxidants (TAWSA) of chitosan and high protein microbiologically synthesized concentrate as FAFAs; to assess the effect of these FAFAs on TAWSA values, parameters of sheep blood serum and rumen content by biochemical, physical and chemical methods. The laboratory studies of TAWSA values of feed components based on chitosan from different manufacturers or/and a high-protein concentrate were implemented. The animal experiments were carried out on six rumen-fistulated ewes (in three rounds of 14 days each, i.e., three groups) to confirm the results of the laboratory studies. The particular differences of the TAWSA of sheep blood by using both FAFAs by amperometric method were determined. A strong negative correlation −0.67 (or −0.86) was observed between TAWSA and the total protein (globulin’s) content in the blood for the Group 3 of animals. A moderate (0.40) or strong (0.73) positive correlation between TAWSA and total protein content in the blood for the Group 2 of animals than weak correlation 0.23 (or 0.26) for the control Group 1. In conclusion, the correlations between the value changes of TAWSA vs. major biochemical parameters of a blood serum of rumen-fistulated ewes (Group 3 > Group 2 > Group 1) or some indicators of the rumen content (ingesta pH, total content of volatile fatty acids, etc.) were found for the first time.
The aim of the work was to study the correlations between the total amount of water-soluble antioxidants (TAWSA) and biochemical parameters (BC) of cow milk depending on the somatic cell count (SCC). ...The BC and TAWSA values of cow milk were measured by spectroscopic and amperometric methods, respectively. The milk samples from the black-and-white cows (Moscow region) were divided according to SCС values: (1) ≤200, (2) 200-499, (3) 500-999, and (4) ≥1000 thousand units/mL. The average TAWSA values for groups 1, 2, 3, and 4 (33, 15, 13, and 12 milk samples) were the following: 15.95±0.74, 14.45±0.84, 16.04±0.63, and 14.58±1.18. The correlations between TAWSA and BC (group 1) were the following: total fat percentage (TFP) -0.305; true protein percentage (TP1) -0.197; total nitrogen percentage (TN2) -0.210; lactose -0.156; solids-not-fat (SNF) -0.276; total dry matter (TDM) -0.399; freezing point (FP) -0.112; pH -0.114; somatic cell count (SCC) - (-0,052). The correlations between TAWSA and BC (group 2) were the following: TFP -0.332; TP1 -0.296; TN2 -0.303; lactose - (-0.308); SNF -0.159; TDM -0.391; FP -0.226; pH - (-0.211); SCC -0.193. The correlations between TAWSA and BC (group 3) were the following: TFP - (-0.352); TP1 - (-0.411); TN2 – (-0.401); lactose - (-0.166); SNF - (-0.462); TDM - (-0.504); FP - (-0.766); pH - (-0.047); SCC - (-0.698). The correlations between TAWSA and BC (group 4) were the following: TFP -0.159; TP1 -0.046; TN2 – 0.077; lactose - (-0.317); SNF - (-0.237); TDM -0.058; FP - (-0.036); pH - (-0.477); SCC - (-0.072). These data are important in assessing the physiological-biochemical status and state of the antioxidant defense system of cows’ organism.
Lipases play an important role in numerous metabolic reactions in all living species and may be activated at interfaces by some biopolymers in vivo, but inhibited—in vitro. The effect of two chitosan ...samples with different molecular weights on the activity of lipase from porcine pancreas (LPP) in triacetin hydrolysis was investigated. An equimolar amount or excess of chitosan activates LPP by a factor of 1.2 to 1.6. In order to support these data, a negatively charged polyelectrolyte—sodium polystyrene sulfonate (PSS)—was used instead of chitosan. A small increase in LPP activity was found also at an equimolar amount or excess of PSS. This unexpected effect can be explained as “interfacial activation” of LPP with opening of the hydrophobic channel for triacylglycerol hydrolysis. The observed activation effect is important for fundamental biochemistry of human and animal digestion models, as well as for further lipase applications.
Graphical abstract
Possible molecular interactions between chitosan and lipase from porcine pancreas
Feed additives are widely used to enrich animal diets in order to optimize digestive and metabolic processes. However, variations in the technology of preparation of even single-component ...compositions can play a significant role in the effects of their use. The effects of chitosan as a feed additive for animals on various digestive processes are important to study because of the animal nutrition and production quality, healthcare and farming, etc. We studied the antioxidant activity of various feed components: chitosan from various manufacturers and a high protein microbiologic synthesis concentrate by amperometric method. The antioxidant activity values in the rumen content and sheep blood were then examined and evaluated using these feed additives in the diet. The animal experiments were carried out on six rumen- fistulated ewes (in three groups). The particular tendencies of correlation value changes of the antioxidant activity vs. major biochemical parameters of a blood serum of rumen-fistulated ewes (in three groups) or some indicators of the rumen content were obtained for the first time. These data and correlations can be useful for understanding of the features of the sheep antioxidant status and for the evaluation of the feed additives and factors in sheep nutrition. The effects of chitosan as feed additive for animals (FAFAs) on various digestive processes are an important to study because of the animal nutrition and production quality, healthcare and farming. The aims of this study were to evaluate the total amount of water- soluble antioxidants (TAWSA) of chitosan and high protein microbiologically synthesized concentrate as FAFAs; to assess the effect of these FAFAs on TAWSA values, parameters of sheep blood serum and rumen content by biochemical, physical and chemical methods. The laboratory studies of TAWSA values of feed components based on chitosan from different manufacturers or/and a high-protein concentrate were implemented. The animal experiments were carried out on six rumen-fistulated ewes (in three rounds of 14 days each, i.e., three groups) to confirm the results of the laboratory studies. The particular differences of the TAWSA of sheep blood by using both FAFAs by amperometric method were determined. A strong negative correlation -0.67 (or -0.86) was observed between TAWSA and the total protein (globulin's) content in the blood for the Group 3 of animals. A moderate (0.40) or strong (0.73) positive correlation between TAWSA and total protein content in the blood for the Group 2 of animals than weak correlation 0.23 (or 0.26) for the control Group 1. In conclusion, the correlations between the value changes of TAWSA vs. major biochemical parameters of a blood serum of rumen-fistulated ewes (Group 3 > Group 2 > Group 1) or some indicators of the rumen content (ingesta pH, total content of volatile fatty acids, etc.) were found for the first time. Keywords: sheep blood serum; antioxidant activity; chitosan additives; high- protein concentrate; amperometric method
Sequence preferences of DNA binding proteins are a primary mechanism by which cells interpret the genome. Despite the central importance of these proteins in physiology, development, and evolution, ...comprehensive DNA binding specificities have been determined experimentally for only a few proteins. Here, we used microarrays containing all 10-base pair sequences to examine the binding specificities of 104 distinct mouse DNA binding proteins representing 22 structural classes. Our results reveal a complex landscape of binding, with virtually every protein analyzed possessing unique preferences. Roughly half of the proteins each recognized multiple distinctly different sequence motifs, challenging our molecular understanding of how proteins interact with their DNA binding sites. This complexity in DNA recognition may be important in gene regulation and in the evolution of transcriptional regulatory networks.
Previous studies assessing the prevalence of COVID-19 sequelae in adults and children were performed in the absence of an agreed definition. We investigated prevalence of post-COVID-19 condition ...(PCC) (WHO definition), at 6- and 12-months follow-up, amongst previously hospitalised adults and children and assessed risk factors.
Prospective cohort study of children and adults with confirmed COVID-19 in Moscow, hospitalised between April and August, 2020. Two follow-up telephone interviews, using the International Severe Acute Respiratory and Emerging Infection Consortium survey, were performed at 6 and 12 months after discharge.
One thousand thirteen of 2509 (40%) of adults and 360 of 849 (42%) of children discharged participated in both the 6- and 12-month follow-ups. PCC prevalence was 50% (95% CI 47-53) in adults and 20% (95% CI 16-24) in children at 6 months, with decline to 34% (95% CI 31-37) and 11% (95% CI 8-14), respectively, at 12 months. In adults, female sex was associated with PCC at 6- and 12-month follow-up (OR 2.04, 95% CI 1.57 to 2.65) and (OR 2.04, 1.54 to 2.69), respectively. Pre-existing hypertension (OR 1.42, 1.04 to 1.94) was associated with post-COVID-19 condition at 12 months. In children, neurological comorbidities were associated with PCC both at 6 months (OR 4.38, 1.36 to 15.67) and 12 months (OR 8.96, 2.55 to 34.82) while allergic respiratory diseases were associated at 12 months (OR 2.66, 1.04 to 6.47).
Although prevalence of PCC declined one year after discharge, one in three adults and one in ten children experienced ongoing sequelae. In adults, females and persons with pre-existing hypertension, and in children, persons with neurological comorbidities or allergic respiratory diseases are at higher risk of PCC.
Initial periods and magnetic fields of neutron stars Igoshev, Andrei P; Frantsuzova, Anastasia; Gourgouliatos, Konstantinos N ...
Monthly notices of the Royal Astronomical Society,
07/2022, Volume:
514, Issue:
3
Journal Article
Peer reviewed
Open access
ABSTRACT
Initial distributions of pulsar periods and magnetic fields are essential components of multiple modern astrophysical models. Not enough work has been done to properly constrain these ...distributions using direct measurements. Here, we aim to fill this gap by rigorously analysing the properties of young neutron stars (NSs) associated to supernova remnants (SNRs). In order to perform this task, we compile a catalogue of 56 NSs uniquely paired to SNRs with known age estimate. Further, we analyse this catalogue using multiple statistical techniques. We found that distribution of magnetic fields and periods for radio pulsars are both well described using the lognormal distribution. The mean magnetic field is log10B/G = 12.44 and standard deviation is σB = 0.44. Magnetars and central compact objects do not follow the same distribution. The mean initial period is $\log _{10} P_0 P / \mathrm{s} = -1.04_{-0.2}^{+0.15}$ and standard deviation is $\sigma _{\rm p} = 0.53_{-0.08}^{+0.12}$. We show that the normal distribution does not describe the initial periods of NSs sufficiently well. Parameters of the initial period distribution are not sensitive to the exact value of the braking index.
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