Glycoprotein Content Research Articles

BIOCHEMICAL PARAMETERS OF THE BLOOD OF RATS OF DIFFERENT AGES AFTER FILLING THE METAPHYSEAL DEFECT OF THE FEMUR WITH ALLOGENEIC BONE IMPLANTS WITH LOCAL ADMINISTRATION OF BLOOD PLASMA ENRICHED WITH PLATELETS

A promising method of regenerative medicine is the saturation of allografts with platelet-rich plasma (PRP). Objective. To evaluate the course of metabolic processes after filling a hole defect in the distal metaphysis of the femur with allogeneic bone implants in conditions of additional local administration of allogeneic PRP. Methods. In the model of a hole defect in white rats with the filling of the defect with an allograft, as well as with additional local stimulation of PRP on the 7th day; on the 3rd and 7th days and on the 1st, 3rd and 7th days in blood serum, the content of glycoproteins (GP), chondroitin sulfates (CST), total protein (TP), calcium (Ca), activity alkaline phosphatase (AlP) and acid phosphatase (AcP). The results. 14 day. In the 3-month rats, under one stimulation, an increase in TP and Ca, a decrease in AcP was observed, with two stimulations there was a 1.11 times smaller GP, 1.13 times larger TP and 1.43 times Ca compared to those in rats without stimulation. During three stimulations, the GP was 1.24 times lower than that in animals without stimulation. In the 12-month rats in comparison with the data of rats without stimulation, 1.15 times higher GP, Ca, AlP activity, and 1.44 times more AcP were noted. 28 days of the 3-month rats for one injection exceeded the data of animals without stimulation by 1.34 times for GP, and were inferior to them by 1.31 times for AcP. In the 12-month rats, compared to these animals without stimulation, with three injections, a 1.19 times greater TP was noted. 90 d. In the 3-month rats for one injection showed 1.24 times less CST with 1.28 times lower AlP compared to data from rats without stimulation. 12-month rats exceeded the data of the group without stimulation by 1.43 times for AlP. Conclusions. In rats with an alloimplant (especially at 12 months), an increase in connective tissue formation markers and a decrease in LF activity were observed. Filling the defect with an alloimplant led to an increase in inflammation indicators and an increase in markers of bone tissue formation.

Scalable Extraction of Airway Mucins from Porcine Trachea.

Mucins are a major component of the innate defense system in the airways and their biological functions are important to consider in pulmonary disease research. However, the available mucus models for basic research relevant to the lung can be difficult to acquire in sufficient quantity to conduct such studies. Here, we present a new strategy to isolate airway mucins from pig trachea at the milligram to gram scale for use in pulmonary disease research. Using this protocol, we were able to isolate mucins with minimal DNA contamination consisting of ∼70% by weight protein. Compared to porcine gastric mucins extracted with the same procedure, the porcine tracheal extract possessed significantly greater O-linked glycoprotein (mucin) content. Particle tracking microrheology was used to evaluate the biophysical properties of porcine trachea mucins. We found porcine tracheal mucins formed a much tighter mesh network and possessed a significantly greater microviscosity compared to lab extracted porcine gastric mucins. In comparison to mucus harvested from human airway tissue cultures, we found porcine tracheal mucins also possessed a greater microviscosity suggesting these mucins can form into a gel-like material at physiological total solids concentrations. These studies establish an accessible means to isolate airway mucins from porcine trachea at large scale for use in pulmonary disease research.

A gain of function variant in RGS18 candidate for a familial mild bleeding syndrome

BackgroundInherited platelet diseases are bleeding disorders characterized by either defects in platelet count or platelet function, the latter being less common and very heterogeneous. Numerous gene variants associated with abnormal receptors, granules, and signaling pathways have been reported. Despite significant advancements in our understanding, many patients still lack a precise diagnosis. ObjectivesTo identify the genetic basis of a novel mild bleeding syndrome in a family exhibiting a selective defect of platelet aggregation. MethodsOur study included 6 family members across 3 generations who displayed reduced platelet aggregation in response to adenosine diphosphate, PAR1-AP, arachidonic acid, and epinephrine but not collagen. Platelet morphology, granule content, and expression of major surface glycoproteins were all found to be normal. Whole exome sequencing was performed for affected and nonaffected family members. ResultsWe identified RGS18, which encodes the regulator of G protein signaling (RGS) 18, as a candidate gene for the platelet function defect observed in this family. The RGS18 protein serves as a crucial negative regulator of G protein-coupled receptor signaling and coordinates the signaling pathways of natural platelet inhibitors. The heterozygous RGS18 c.643C>T, p.Arg215∗ variant was found to cosegregate among all 6 affected subjects. ConclusionTruncation at Arg215 removes the S216 and S218 phosphorylation sites, which are crucial regulatory domains for RGS18 activation. The impaired platelet function is thought to arise from excessive platelet downregulation due to constitutive activation of RGS18, resulting from a loss of association of the truncated form with the 14-3-3 protein.

The ultrasonic-assisted enzymatic extraction, characteristics and antioxidant activities of lychee nuclear polysaccharide

A response surface methodology (RSM) and one-factor method were established to investigate the optimum conditions for the extraction of lychee nuclear polysaccharides (LSP) by ultrasonic-assisted pectinase. The content of basic components in polysaccharides was determined. The antioxidant activity was well determined and compared the differences in the activities of the polysaccharides extracted by water extraction (LSP-HW) and those extracted at ultrasound-assisted enzyme (LSP-UAE). The activity of lychee nuclear polysaccharide increased with the increase of concentration. The anti-hydroxyl radical and anti-lipid peroxidation abilities of lychee nuclear polysaccharide were more excellent, and LSP-HW was slightly better than LSP-UAE in terms of activity, but the difference was not significant. In terms of solubility; LSP-HW without deproteinization was the best, followed by LSP-UAE, and the worst was LSP-UAE after deproteinization. The higher the glycoprotein content, the better the solubility of its polysaccharide. Compared with the existing extraction methods, this experiment greatly improved the extraction rate of lychee nuclear polysaccharides and further enriched the antioxidant activities of polysaccharides.

Extraction optimization, partial purification, and characterization of sialoglycoproteins from Labeo rohita roes

In India, fish roes are generally considered worthless garbage and disposed of without recovering the valuable molecules, creating environmental and disposal problems. The present investigation aimed to optimize the extraction conditions, partial purification, and characterization of sialoglycoproteins (RRSGP) from Labeo rohita (rohu) roes. RSM generated optimum conditions for maximum RRSGP (70.49 %) extraction, which were 1.25 M NaCl, 1:32.5(w/v) solid-to-liquid ratio, 47.5 °C temperature, and 3 h time. Further, sialoglycoproteins from RRSGPs were partially purified, and result revealed that obtained peak-1 (PRRSGP) using QFF anion exchange chromatography exhibited higher glycoprotein and sialic acid content (p < 0.05). SDS-PAGE pattern of PRRSGP presented dominant bands of 97 kDa and 27 kDa glycoproteins. FTIR spectrum of PRRSGP confirmed the presence of glycated proteins. HPLC analysis revealed that PRRSGP consists of Neu5Ac. Furthermore, β-elimination reaction elucidated that PRRSGP contained N-glycosidic linkage. PRRSGP exhibited tyrosine and glutamate as primary amino acids. Glycan part of PRRSGP presented mannose and N-acetyl galactosamine as dominant neutral and amino sugar, respectively. Furthermore, PRRSGP exhibited antioxidant activity with EC50 value for DPPH (8.79 mg/ml) and ABTS (2.21 mg/ml). Besides, RRSGP displayed better protein solubility, foaming, and emulsion properties. Therefore, rohu roes are potential source of sialoglycoproteins that can be recovered and used as bio-functional ingredients in food and nutraceutical applications.

Cellular immunity in women aged 20–40 living in different climatic and geographic regions

The aim. To identify phenotypic features of adaptive cellular immune responses in young women living in different climatic and geographic regions.Materials and methods. We examined 63 apparently healthy women, including 25 residents of Sovpolye settlement, Arkhangelsk region (Arctic region) and 38 residents of Tskhinvali (Republic of South Ossetia) aged 20–40. The content of lymphocytes, their phenotypes CD4+, CD8+, CD3+, CD5+, CD16+, CD10+, CD71+, CD25+, HLA-DR+ and CD95+, CEA (carcinoembryonic antigen) glycoprotein, and interleukin (IL) 6 and IL-10 cytokines was studied. Lymphocytes phenotyping was performed by indirect immunoperoxidase reaction using monoclonal antibodies (MedBioSpektr, Moscow) on “dried drop” lymphocyte sample with peroxidase conjugate and chromogen solution staining for immersion microscopy analysis (Nicon 50i, Japan). The content of CEA glycoprotein and cytokines was determined using ELISA.Results. In women living in Arctic region, a deficiency of CD5+, CD3+, CD10+, CD95+, CD71+, CD25+, HLA-DR+ cells, CEA and IL-6 concentrations is associated with high concentrations of CD8+ and IL-10. In women living in Southern region, a slight deficiency of CD5+, CD8+ and CD95+ cells is associated with high concentrations of CEA, IL-6, IL-10 and CD10+, CD16+ and HLA-DR+ cells.Conclusion. In inhabitants of different climatic regions, the features of formation of adaptive immune reactions are determined by different quantitative and qualitative composition of lymphocytes and cytokines phenotypes. Reduction of reserve capabilities of immune homeostasis is detected 3 times more often in inhabitants of the Arctic region.

Using a Sandwich ELISA to Determine the Immunogenic Glycoprotein Content in a Vaccine

Using a Sandwich ELISA to Determine the Immunogenic Glycoprotein Content in a Vaccine

Using a Sandwich ELISA to Determine the Immunogenic Glycoprotein Content in a Vaccine

Using a Sandwich ELISA to Determine the Immunogenic Glycoprotein Content in a Vaccine

Quality of edible bird’s nest treated by keratinolytic enzymes-based cleaning solution

Edible bird's nest (EBN) is one of the luxury foods that is widely used as a healthy food due to its nutritional value and therapeutic benefits. The traditional EBN washing process causes a reduction in weight and nutrient content and an increase in pollutants due to the use of hydrogen peroxide. An exploratory observation method was used to examine the quality of EBN from Collocalia fuciphaga before and after washing using a washing solution based on keratinolytic enzymes. There are four stages of EBN cleaning i.e. cleaning by tap water, ethanol solution, enzyme solution at room temperature and 50oC and drying at 40oC for 42 hrs. A total of 60 EBN (unclean, n = 30) and clean, n = 30) were analyzed using the AOAC method. The mineral content of Ca, Fe, K and Mg using atomic absorption spectrophotometry (AAS) except that P was measured by spectrophotometer. A carbohydrate estimation kit was used to measure glycoprotein content and the amino acid content was determined using the HPLC method. Evaluation of the cleanliness was carried out using a scoring system by semi-trained panelists. The results obtained showed that the clean EBNs were slightly yellowish-white in color, and the cleanliness of EBN before and after cleaning increased from 2.35 to 3.84. Clean EBN protein content decreased by 7.2% while total amino acids decreased from 38.51% to 32.71%. Clean EBN contains eight essential amino acids of 17.93% with high levels of leucine, valine, arginine, and threonine (2.42-2.96%). EBN's clean ash content increased from 3.7% to 7.8%. Carbohydrate content and iron in clean EBN were 39.19±0.76% and 14.35 mg/100 g dry matter, respectively. The high levels of carbohydrates and iron appear to be good sources of glycoprotein to support health and have the potential as an alternative source of iron for people with anemia. The stepwise EBN washing method using tapwater, ethanol and a washing solution based on keratinolytic enzymes can be applied to reduce weight loss and improve the quality of EBN.

Potency, immunogenicity, and efficacy of rabies vaccine: In vitro and in vivo approach.

Rabies, a potentially lethal virus, affects more than 150 countries. Although the rabies vaccine and immunoglobulin have been available since 1908, Bangladesh is new to vaccine manufacturing. We checked the quality of the local manufacturing rabies vaccine for substandard. The potency and immunogenicity of 20 vaccines were analyzed by three in vivo and in vitro methods from March 2020 to May 2023. Single radial immunodiffusion, fluorescent antibody virus neutralization, and national institutes of health tests were carried out to evaluate the vaccine's efficacy to provide sufficient protection against the rabies virus. The potency of the rabies vaccine was determined by the in vitro SRID method by measuring glycoprotein content. An average of 16 articles from each batch was calculated. The minimum and maximum average mean values of the 20 batches were 5.058 and 5.346, respectively. The variance was calculated at 0.00566. We found a coefficient of variation (CV) between 9.36% and 14.80%. The 100% sample was satisfactory, as these samples had a potency of over 2.5 IU/mL. To observe immunogenicity, we applied the FAVN method for determining antibody titers. An average of 16 articles from every batch were counted to quantify antibody titers. The mean quantity of antibody titers ranged from 2.389 to 3.3875. The CV was slightly lower because of the dispersion of the data. At last, we performed an in vivo method, the NIH test method, to determine potency based on mortality rate. We found a mean value of 4.777 IU/SHD with a standard deviation of 1.13 IU/SHD. All 20 batches were found 100% satisfactory in the NIH test. The study implies that the rabies human vaccines manufactured in Bangladesh are potent enough to provide sufficient immunogenicity. Our research is warranted testimony for healthcare providers who work to extirpate rabies.

Perfusion filtration technology for the cultivation of VNK-21/13-13 cells for the manufacture of rabies vaccine

The possibility of practical use of perfusion cell culture technology VNK-21/13-13 was evaluated in the manufacture of rabies vaccine using bioreactors with a working volume of 5 liters and 100 liters. The purpose of this study is to develop a highly effective technology for perfusion continuous suspension cultivation of the transplanted BHK– 21/13-13 cell line, suitable for use as a cellular substrate in the manufacture of rabies vaccine. Using Cytiva filter elements made of PES membrane material with a retention rating of 0.65 microns, a cell density above 7× 106 cells/ml was achieved for the subsequent production of a viral suspension. The glycoprotein content measured by the ELISA method reached a maximum on the 4th day after infection, was 5 IU/ml. The maximum cell accumulation and glycoprotein content in the 5 L bioreactor was more than 2-3 times higher than for the serial production of rabies vaccine. When reproducing the rabies virus in a 100 l bioreactor after perfusion cultivation, the cell concentration was 16-20 million/ml with a viability of 95.4%. The highest content of the virus glycoprotein was also achieved in a bioreactor with a working volume of 100 liters 4 days after infection and amounted to 8 IU/ ml. Sequencing of the glycoprotein gene revealed the genetic stability of the main immunogenicity protein, which is an important indicator for controlling the stability of the virus during many passages in vaccine production using a perfusion system.

Comparison of the Eggshell and the Porcine Pericardium Membranes for Guided Tissue Regeneration Applications.

Guided bone regeneration is frequently used to reconstruct the alveolar bone to rehabilitate the mastication using dental implants. The purpose of this article is to research the properties of eggshell membrane (ESM) and its potential application in tissue engineering. The study focuses on the structural, mechanical, and histological characteristics of ESM extracted from Gallus domesticus eggs and to compare them to a commercially available porcine pericardium membrane (Jason® membrane, botiss biomaterials GmbH, Zossen, Germany). Thus, histology was performed on the ESM, and a comparison of the microstructure through scanning electron microscopy and atomic force microscopy (AFM) was conducted. Also, mechanical tensile strength was evaluated. Samples of ESM were prepared and treated with alcohol for fixation and disinfection. Histological analysis revealed that the ESM architecture is constituted out of loose collagen fibers. However, due to the random arrangement of collagen fibers within the membrane, it might not be an effective barrier and occlusive barrier. Comparative analyses were performed between the ESM and the AFM examinations and demonstrated differences in the surface topography and mechanical properties between the two membranes. The ESM exhibited rougher surfaces and weaker mechanical cohesion attributed to its glycoprotein content. The study concludes that while the ESM displays favorable biocompatibility and resorb ability, its non-uniform collagen arrangement limits its suitability as a guided bone regeneration membrane in the current non-crosslinked native form. Crosslinking techniques may enhance its properties for such applications. Further research is needed to explore modifications and processing methods that could leverage the ESM's unique properties for tissue engineering purposes.

Splenectomy improves erythrocyte functionality in spherocytosis based on septin abundance, but not maturation defects.

Splenectomy improves the clinical parameters of patients with hereditary spherocytosis, but its potential benefit to red blood cell (RBC) functionality and the mechanism behind this benefit remain largely overlooked. Here, we compared 7 nonsplenectomized and 13 splenectomized patients with mutations in the β-spectrin or the ankyrin gene. We showed that hematological parameters, spherocyte abundance, osmotic fragility, intracellular calcium, and extracellular vesicle release were largely but not completely restored by splenectomy, whereas cryohemolysis was not. Affected RBCs exhibited decreases in β-spectrin and/or ankyrin contents and slight alterations in spectrin membrane distribution, depending on the mutation. These modifications were found in both splenectomized and nonsplenectomized patients and poorly correlated with RBC functionality alteration, suggesting additional impairments. Accordingly, we found an increased abundance of septins, small guanosine triphosphate-binding cytoskeletal proteins. Septins-2, -7, and -8 but not -11 were less abundant upon splenectomy and correlated with the disease severity. Septin-2 membrane association was confirmed by immunolabeling. Except for cryohemolysis, all parameters of RBC morphology and functionality correlated with septin abundance. The increased septin content might result from RBC maturation defects, as evidenced by (1) the decreased protein 4.2 and Rh-associated glycoprotein content in all patient RBCs, (2) increased endoplasmic reticulum remnants and endocytosis proteins in nonsplenectomized patients, and (3) increased lysosomal and mitochondrial remnants in splenectomized patients. Our study paves the way for a better understanding of the involvement of septins in RBC membrane biophysical properties. In addition, the lack of restoration of septin-independent cryohemolysis by splenectomy may call into question its recommendation in specific cases.

Cell wall polysaccharide and glycoprotein content tracks growth-form diversity and an aridity gradient in the leaf-succulent genus Crassula.

Cell wall traits are believed to be a key component of the succulent syndrome, an adaptive syndrome to drought, yet the variability of such traits remains largely unknown. In this study, we surveyed the leaf polysaccharide and glycoprotein composition in a wide sampling of Crassula species that occur naturally along an aridity gradient in southern Africa, and we interpreted its adaptive significance in relation to growth form and arid adaptation. To study the glycomic diversity, we sampled leaf material from 56 Crassula taxa and performed comprehensive microarray polymer profiling to obtain the relative content of cell wall polysaccharides and glycoproteins. This analysis was complemented by the determination of monosaccharide composition and immunolocalization in leaf sections using glycan-targeting antibodies. We found that compact and non-compact Crassula species occupy distinct phenotypic spaces in terms of leaf glycomics, particularly in regard to rhamnogalacturonan I, its arabinan side chains, and arabinogalactan proteins (AGPs). Moreover, these cell wall components also correlated positively with increasing aridity, which suggests that they are likely advantageous in terms of arid adaptation. These differences point to compact Crassula species having more elastic cell walls with plasticizing properties, which can be interpreted as an adaptation toward increased drought resistance. Furthermore, we report an intracellular pool of AGPs associated with oil bodies and calcium oxalate crystals, which could be a peculiarity of Crassula and could be linked to increased drought resistance. Our results indicate that glycomics may be underlying arid adaptation and drought resistance in succulent plants.

Altered Secretion, Constitution, and Functional Properties of the Gastrointestinal Mucus in a Rat Model of Sporadic Alzheimer's Disease.

The gastrointestinal (GI) system is affected in Alzheimer's disease (AD); however, it is currently unknown whether GI alterations arise as a consequence of central nervous system (CNS) pathology or play a causal role in the pathogenesis. GI mucus is a possible mediator of GI dyshomeostasis in neurological disorders as the CNS controls mucus production and secretion via the efferent arm of the brain-gut axis. The aim was to use a brain-first model of sporadic AD induced by intracerebroventricular streptozotocin (STZ-icv; 3 mg/kg) to dissect the efferent (i.e., brain-to-gut) effects of isolated central neuropathology on the GI mucus. Morphometric analysis of goblet cell mucigen granules revealed altered GI mucus secretion in the AD model, possibly mediated by the insensitivity of AD goblet cells to neurally evoked mucosal secretion confirmed by ex vivo cholinergic stimulation of isolated duodenal rings. The dysfunctional efferent control of the GI mucus secretion results in altered biochemical composition of the mucus associated with reduced mucin glycoprotein content, aggregation, and binding capacity in vitro. Finally, functional consequences of the reduced barrier-forming capacity of the mucin-deficient AD mucus are demonstrated using the in vitro two-compartment caffeine diffusion interference model. Isolated central AD-like neuropathology results in the loss of efferent control of GI homeostasis via the brain-gut axis and is characterized by the insensitivity to neurally evoked mucosal secretion, altered mucus constitution with reduced mucin content, and reduced barrier-forming capacity, potentially increasing the susceptibility of the STZ-icv rat model of AD to GI and systemic inflammation induced by intraluminal toxins, microorganisms, and drugs.

An inulin-type fructan isolated from Serratula chinensis alleviated the dextran sulfate sodium-induced colitis in mice through regulation of intestinal barrier and gut microbiota

Herein, we aimed to explore the polysaccharide material basis of Serratula chinensis and establish its beneficial effects against colitis. A neutral polysaccharide (SCP) was extracted from S. chinensis in high yield using hot water. The molecular weights were calculated by HPSEC as Mw = 2928 Da, Mn = 2634 Da, and Mw/Mn = 1.11. FT-IR and 1D/2D-NMR spectroscopic analyses confirmed that SCP was an inulin-type fructan with α-D-Glcp-(1 → [1)-β-D-Fruf-(2]17) linkages. Treatment with SCP (200 or 400 mg/kg) alleviated dextran sulfate sodium (DSS)-induced mouse colitis symptoms, including the loss of body weight, increase of disease activity index score, and shortening of colon length. Histopathological and immunofluorescence assessments revealed that SCP could reduce pathological damage to the colon, restore the number of goblet cells, increase the content of glycoproteins in goblet cells and mucins in crypts, and enhance the expression of tight junction proteins ZO-1 and occludin. In addition, metagenomic sequencing revealed that SCP could improve the dysbiosis of gut microbiomes and act on multiple microbial functions. Moreover, SCP treatment increased the content of colonic acetic acid and butanoic acid. Collectively, these results indicated that SCP could alleviate the DSS-induced colitis in mice through regulation of intestinal barrier and gut microbiota.

CHANGES IN MARKERS OF BONE TISSUE REMODELING AND THE INFLAMMATORY PROCESS IN THE BLOOD SERUM OF WHITE RATS IN CASE OF DEFECT FILLING OF THE FEMUR WITH IMPLANTS BASED ON POLYLACTIDE AND TRICALCIUMPHOSPHATE WITH MESENCHYMAL STEM CELLS

Objective. Based on the analysis of markers of inflammation and metabolism of bone tissue in the blood serum of laboratory rats, to evaluate the course of bone remodeling after filling the defect in the distal metaphysis of the femur with 3D-printed implants based on polylactide and tricalcium phosphate (3D-I) alone or in combination with mesenchymal stromal cells (MSCs). Methods. 53 white rats were used, which were divided into groups: intact (5 animals) — the operation was not performed; Control (15) — 3D-I; Experiment I (15) — 3D-I + cultured alloMSCs; Experiment II (15) — 3D-I + introduction of alloMSCs into the area of surgical intervention 7 days after implantation. The following were studied: the content of glycoproteins (GP), interleukin-6 (IL-6), osteocalcin, chondroitin sulfates (CS), total protein, calcium, alkaline (AlP) and acid phosphatase (AP) activity, and their ratio, mineralization indices were calculated. Results. Compared with intact animals, higher indicators were determined in the rats of the Control group: the content of GP by 39.73; 32.88; 23.29 %; CS — 250.00; 222.09 and 196.51 %, AlP activity — 81.67, 51.03, 39.36 %, on the 15th, 30th, and 90th days of the experiment; IL-6 — 44.89; 60.06 % on the 15th and 30th days. In the rats of the Experiment I g roup: the content of GP — by 82.19; 65.75, 57.53 %, IL-6 — 72.14; 96.59; 79.88 %, CS — 306.98; 276.74; 253.49 %; AlP activity — 63.73; 129.70; 51.28 %, on the 15th, 30th and 90th days of the experiment. In the Experiment II group: on the 15th, 30th and 90th days, the content of GP was higher by 27.40; 26.03; 129.18 %; CS — by 175.58; 137.21 and 115.12 %; AlP activity — 192.99; 178.02, 76.31 %; on the 15th and 30th days: IL-6 — by 37.46; 20.74 %. Conclusions. In the case of filling the defect with 3D-printed implants, biochemical signs of moderate inflammation were determined; 3D-printed implants together with MSCs — pronounced inflammation, slowing of bone formation, formation of connective tissue; 3D-printed implants with postoperative injection of MSCs — moderate inflammation and optimal conditions for healing the defect with bone tissue.

BIOCHEMICAL INDICATORS OF BLOOD SERUM OF RATS OF DIFFERENT AGES AFTER FILLING THE DEFECT IN THE METAPHYSIS OF THE FEMUR WITH ALLOGENEIC BONE IMPLANTS

Bone defects that do not heal on their own are a significant problem in orthopaedic and trauma surgery. One of the approaches to its solution is the use of bone alloimplants (AloI). Objective. On the basis of the analysis of biochemical indicators of the metabolism of connective tissue in the blood serum of laboratory rats, the course of metabolic processes after the filling of the defect in the metaphysis of the AloI femur was evaluated. Methods. A model of creating a transcortical defect of critical size (diameter 3 mm, depth 3 mm) in the metaphysis of the femur of 3- and 6-month-old rats was used. In animals of groups I (n = 15, age 3 months) and III (n = 15,12 months) the defects were left unfilled, II (n = 15, 3 months) and IV (n = 15, 12 months) — filled with structural AloI. After 14, 28 and 90 days, the content of glycoproteins, total chondroitin sulphates (CS), protein and calcium, activity of alkaline and acid phosphatases in blood serum was investigated. Results. The introduction of AloI leads to an increase in the content of glycoproteins for all periodsof observation in rats of both age groups. 14 days after implantation in 12-month-old rats, compared to 3-month-old rats, a 1.30 times higher level of CS in blood serum was determined (p = 0.008), which is due to their higher content in the area of connective tissue implantation; the activity of alkaline phosphatase decreased by 1.80 times p = 0.016) and acid phosphatase by 1.50 times (p = 0.018), which indicates a delay in the formation and reorganization of bone tissue. However, the level of CS under the conditions of the establishment of AloI on the 90th day was lower compared to the correspondinggroups without plasticity of the defect: in 3-month-old rats by 1.44 times ( p = 0.008), in 12-month-old rats by 1.52 times (p = 0.008). Conclusions. According to the indicators of biochemical markers of connective tissue metabolism, the use of AloI for plasticity of defects of a critical size in the metaphysis of the femur of rats leads to the activation of bone regeneration with a greater manifestation in younger recipients compared to groups with an unfilleddefect.

Changes in the indicators of connective tissue metabolism in the blood serum of experimental rats under the conditions of modeling the development of degenerative processes in paravertebral muscles

Low back pain is a common health problem. To deepen the understanding of the pathogenesis of the disease, experimental studies on animals with modeling of the pathological process are necessary. Objective. Based on the analysis of biochemical markers of connective tissue metabolism in the blood serum of laboratory rats, the applicability of the studied models of degenerative muscle tissue damage to study the relationship between this condition and the development of disorders in spinal motor segments was assessed. Methods. Two models of reproduction of degenerative processes in the paravertebral muscles of white rats were tested: I (n = 5) — alimentary (diet-induced) obesity, by keeping it for 3 months on a high-calorie diet; II (n = 5) — ischemia, by tying the large rectus muscles of the back with suture material (45 days). Control group (n = 5) — intact animals of similar age and sex. The content of glycoproteins, total chondroitin sulfates (CS), hexosamines, protein-bound hexoses, seroglycoides, fractional distribution and total content of hydroxyproline and glycosaminoglycan sulfates (GAGs) were investigated in the blood serum of rats. The results. In the blood serum of rats of groups I and II, a significant increase compared to the control level of glycoproteins was determined, with a greater effect in the ischemia model, but no significant changes of protein-bound hexoses, hexosamines and CS were recorded. The level of inflammatory markers (sialic acids and seroglycoides) in the blood serum of animals of both groups did not differ significantly from the control, and changes in the parameters of hydroxyproline (except for the slightly changed protein-bound fraction) and GAGs were significant only for the ischemia model. Conclusions. Based on the analysis of biochemical markers of connective tissue metabolism in rats of groups I and II, changes characteristic of degenerative processes were determined, with a greater manifestation in the ischemia model. No significant increase in biochemical markers of inflammation was recorded. Both models can be used to reproduce dystrophic processes in osteochondrosis.

Characterization of PcSTT3B as a Key Oligosaccharyltransferase Subunit Involved in N-glycosylation and Its Role in Development and Pathogenicity of Phytophthora capsici.

Asparagine (Asn, N)-linked glycosylation is a conserved process and an essential post-translational modification that occurs on the NXT/S motif of the nascent polypeptides in endoplasmic reticulum (ER). The mechanism of N-glycosylation and biological functions of key catalytic enzymes involved in this process are rarely documented for oomycetes. In this study, an N-glycosylation inhibitor tunicamycin (TM) hampered the mycelial growth, sporangial release, and zoospore production of Phytophthora capsici, indicating that N-glycosylation was crucial for oomycete growth development. Among the key catalytic enzymes involved in N-glycosylation, the PcSTT3B gene was characterized by its functions in P. capsici. As a core subunit of the oligosaccharyltransferase (OST) complex, the staurosporine and temperature sensive 3B (STT3B) subunit were critical for the catalytic activity of OST. The PcSTT3B gene has catalytic activity and is highly conservative in P. capsici. By using a CRISPR/Cas9-mediated gene replacement system to delete the PcSTT3B gene, the transformants impaired mycelial growth, sporangial release, zoospore production, and virulence. The PcSTT3B-deleted transformants were more sensitive to an ER stress inducer TM and display low glycoprotein content in the mycelia, suggesting that PcSTT3B was associated with ER stress responses and N-glycosylation. Therefore, PcSTT3B was involved in the development, pathogenicity, and N-glycosylation of P. capsici.