Morphological rearrangement of the metabolic link of the microcirculatory bed of guinea pigs lungs after sensitization with ovalbumin

The reaction of the lung microvessels is an urgent issue of morphology and medicine in general, as well as one of the insufficiently investigated points in the study of morphological changes in chronic allergic diseases of the respiratory system. The aim is to study the morphological changes in the vessels of the metabolic link of the microcirculation in the lungs of guinea pigs sensitized with ovalbumin. Materials and methods. We have studied the lungs of 48 guinea pigs, using histological and morphometric methods, under conditions of experimental ovalbumin-induced allergic inflammation, simulated by three-time subcutaneous sensitization and subsequent 8-day intranasal inhalation of ovalbumin. To estimate the structural and functional state of capillaries, the inner diameter of the vessels was determined. Results. A general regularity in the reactivity of the hemomicrocirculatory bed of guinea pig lungs in experimental ovalbumin-induced allergic inflammation was established, which consists in a significant structural and functional restructuring of the exchange vessels of the microcirculatory bed. Dysfunction of the capillaries endothelium is manifested by a change of vasodilatation to vasospasm, as evidenced by morphometric changes in the diameter of the capillaries lumen in the experimental groups, and an increase in the permeability of the capillaries wall, which is confirmed by edema and disorganization of the connective tissue component. Conclusions. Allergic inflammation leads to structural and functional reorganization of the metabolic link of the hemomicrocirculatory bed of guinea pig lungs, which has a multidirectional staging character depending on the duration of the experiment and is a manifestation of a violation of the compensatory-adaptive processes of hemomicrocirculation. The most pronounced changes in the form of a decrease in the diameter of the lumen of the blood capillaries of the lungs of guinea pigs by 23 % compared to the control are observed during the late period of the development of the allergic inflammatory process.

Features of skeletal muscle structure in Smena-8 and Andalusian Blue chickens in separate periods of postembryonic ontogenesis

Histological and morphological characteristics of skeletal muscles in chickens of the meat direction of productivity Smena-8 and egg direction of productivity Andalusian blue on the 20th and 29th days of postembryonic development are presented. The skeletal striated muscle tissue of the studied bird obeys the general principles of myogenesis inherent in most animal species and is characterized by signs of a definitive structure. It is shown that on the 20th and 29th days of postembryonic ontogenesis in the Smena-8 cross and the Andalusian blue breed, the quadriceps femoris is ahead of the superficial pectoral muscle in terms of the thickness of muscle fibers. The thickness of the endomysium and perimysium in the connective tissue component of the superficial pectoral muscle in chickens of both directions of productivity prevails over that in the quadriceps femoris. Based on the obtained morphometric parameters of the structure of muscle fibers, the concept of myogenesis of skeletal muscles in agricultural poultry of egg and meat productivity directions is presented.

Micromorphological characteristics of the superficial pectoral muscle in Kulangi and Malay fighting chickens

On the basis of histological and micromorphometric studies, the general regularities and breed features of the structural organization of the superficial pectoral muscle in chickens of the meat production direction Kulangi and Malajskaya bojcovaya hens are presented. The age of the studied individuals was 1 and 29 days. The study evaluated the structural and morphometric parameters of not only the muscle fibers, but also the connective tissue component of the studied muscle. It is shown that representatives of fighting breeds of the meat direction of productivity are characterized by general patterns and distinctive features of the structure of the muscle tissue of the superficial pectoral muscle. The similarity of all the studied samples of muscle tissue in terms of area was revealed, which indicates that this feature has optimal values and is stable during ontogenesis. At the same time, the parameters of the thickness of the endomysium, peremysium, muscle fibers and their bundles had variable values in all the studied bird breeds on the 1st and 29th days of ontogenesis. The data obtained indicate the presence of both common morphological features of muscle tissue, genetically determined and stable regardless of productivity, and variable, which can change under the influence of selection. The results of the research are important for veterinary biology, industrial poultry farming, veterinary and sanitary expertise and can be used to improve the methods of breeding work.

Features of the microorganization of the superficial pectoral muscle in chickens of meat and egg areas of productivity

On the basis of histological and micromorphometric studies, general patterns and breed features of the structural organization of the superficial pectoral muscle in meat (Smena-8, Cobb-500) and egg (Hisex white, Andalusian blue) productivity directions are presented. The age of the examined individuals is 29 days. The study evaluated the structural and morphometric parameters of not only muscle fibers, but also the connective tissue component of the muscle under study. It is shown that representatives of meat breeds surpass representatives of egg breeds in terms of muscle fiber thickness and perimisia. At the same time, the indicators of the thickness of the endomysium, bundles of muscle fibers and the area of muscle tissue had similar values in all studied birds. The data obtained indicate the presence of both common morphological traits of muscle tissue, genetically determined and stable regardless of productivity, and variable, which can change under the influence of selection. The research results are important for biology, comparative, species and breed morphology, as well as for veterinary and sanitary examination of chicken meat and in poultry farming to assess the purity of the breed.

Histochemical changes during development of Harderian gland in chicken

The present study was aimed to examine histochemical changes in the Harderian gland of pre and post hatched chicks from 11 day of incubation to 24 days of age. In pre hatched groups, the gland was in the developing stage. There was no well defined parenchyma, septa and capsule in early embryonic stage. Histochemical observation revealed that weak or negligible activity of PAS, AB/PAS and Sudan black B was seen in epithelial lining of Harderian gland on 18th and 20th day of incubation. The gland was compound tubule-acinar type at 20th day of incubation, consisted of capsule, parenchyma and stroma. PAS activity was seen in the capsule, septa, epithelial lining of acini and tubule and interstitial connective tissue cells. PAS activity was aggregated towards the apical part of the tubular epithelium as well as at the free luminal surface epithelium of the acini. PAS activity increases with the development of connective tissue component of Harderian gland with the advancement of age. The Harderian gland was predominantly mucus and lipid secreting gland. All epithelial cells of the glandular unit of Harderian gland contain both neutral and acidic mucin. Intense AB-positive activity was seen at the apex of tubule with the advancement of age. Sudan black B activity was recorded in the cytoplasm of epithelial lining of tubule and acini of the Harderian gland and their presence increases with age.

Clinical and experimental substantiation of the effect of hypoxia on the wall of the small and large intestine in newborns

Based on the analysis of morphological and morphometric data, the clinical and experimental results of the effect of hypoxia on the wall of the small and large intestine in newborns are presented. The clinical part is based on the study of 58 case histories of patients with necrotizing enterocolitis, which the operating material (resected sections of the small intestine, large intestine) was studied in detail. The experimental work included the modeling of chronic hypobaric hypoxia in different trimesters of pregnancy in 4 groups of white rats (24 females). The offspring was taken out of the experiment at 4-5 days after birth, followed by collection of the small and large intestine areas to study histoarchitectonics. It is proved that hypoxia affects the number of newborn offspring, its weight. The small intestine is most vulnerable to the effect of this factor. Analysis of the morphological and morphometric picture of the operating and experimental material convincingly proves that under the influence of hypoxia the destruction of the intestinal mucosa occurs and the growth of the connective tissue component in the muscle layer occurs. Changes from the microcirculation of blood and lymph provoke the development of pre-ulcerative, ulcerative defects and the formation of necrosis. Disturbance of the drainage function promotes the spread of destruction in the intestinal wall.

Bovine biceps femoris is resistant to tenderization by lower-salt moisture enhancement or enzyme addition

Unacceptable toughness in retail beef cuts prepared from round muscles is not uncommon. The biceps femoris (BF) muscle is a particular challenge due to its high connective tissue content. Disruption of connective tissue by proteolytic enzyme injection has been demonstrated to improve tenderness in some muscles. Moisture enhancement can also be effective; however, concern over sodium content in processed foods is rising. The single and combined effects of lower-salt moisture enhancement (ME; 0.25% sodium chloride/0.25% sodium phosphate) and injection of enzymes from different sources (fungal aspartyl protease, bacterial protease, porcine pancreatin, plant-derived papain) on tenderness characteristics of the BF was examined. The enzyme and ME treatments were not interactive. Moisture enhancement had no impact on peak shear force or sensory tenderness, although juiciness and saltiness perception was enhanced, even at the relatively low salt level. Each enzyme treatment reduced the shear force associated with the myofibrillar component of the BF, but did not influence the connective tissue component. No off flavour development or other sensory defects resulted from enzyme treatment. The ineffectiveness of the treatments may have been due to the low salt level, lack of enzyme specificity for collagen, or the relatively intractable nature of the BF to tenderization treatments.

IgE alone stimulates mast cell adhesion to fibronectin via pathways similar to those used by IgE + antigen but distinct from those used by Steel factor

We recently demonstrated that immunoglobulin E (IgE), in the absence of cross-linking agents, activates signaling pathways in healthy murine bone marrow–derived mast cells (BMMCs) and that this activation enhances BMMC survival, at least in part, via secretion of autocrine-acting cytokines. We report herein that IgE alone also triggers the adhesion of both BMMCs and connective tissue mast cells (CTMCs) to the connective tissue component, fibronectin (FN). This adhesion occurs to the same extent as that triggered by optimal levels of Steel factor (SF) or IgE + antigen (IgE + Ag) and is mediated by an increased avidity of the integrin very late antigen 5 (VLA-5). Moreover, this IgE-induced adhesion, which is prolonged compared with that elicited by SF or IgE + Ag, requires phosphatidylinositol 3-kinase (PI3K), phospholipase C γ (PLCγ), and extracellular calcium but not extracellular-regulated kinase (Erk) or p38. Interestingly, we found, using the calcium channel blocker, 2-APB (2-aminoethoxydiphenyl borate) and Lyn–/– BMMCs that both IgE- and IgE + Ag-induced adhesion to FN require extracellular calcium entry, whereas SF does not. Furthermore, our data suggest that FN acts synergistically with IgE to prolong intracellular phosphorylation events and to enhance IgE-induced inflammatory cytokine production and BMMC survival.