Preservation of collagen in the soft tissues of frozen mammoths

We investigated the characteristics of extracellular matrix (ECM) in the soft tissue of two frozen baby woolly mammoths (Mammuthus primigenius) that died and were buried in Siberian permafrost approximately 40,000 years ago. Morphological and biochemical analyses of mammoth lung and liver demonstrated that those soft tissues were preserved at the gross anatomical and histological levels. The ultrastructure of ECM components, namely a fibrillar structure with a collagen-characteristic pattern of cross-striation, was clearly visible with transmission and scanning electron microscopy. Type I and type IV collagens were detected by immunohistochemical observation. Quantitative amino acid analysis of liver and lung tissues of the baby mammoths indicated that collagenous protein is selectively preserved in these tissues as a main protein. Type I and type III collagens were detected as major components by means of liquid chromatography–mass spectrometry analysis after digestion with trypsin. These results indicate that the triple helical collagen molecule, which is resistant to proteinase digestion, has been preserved in the soft tissues of these frozen mammoths for 40,000 years.

Preservation of collagen in the soft tissues of frozen mammoths

We investigated the characteristics of extracellular matrix (ECM) in the soft tissue of two frozen baby woolly mammoths ( Mammuthus primigenius ) that died and were buried in Siberian permafrost approximately 40,000 years ago. Morphological and biochemical analyses of mammoth lung and liver demonstrated that those soft tissues were preserved at the gross anatomical and histological levels. The ultrastructure of ECM components, namely a fibrillar structure with a collagen-characteristic pattern of cross-striation, was clearly visible with transmission and scanning electron microscopy. Type I and type IV collagens were detected by immunohistochemical observation. Quantitative amino acid analysis of liver and lung tissues of the baby mammoths indicated that collagenous protein is selectively preserved in these tissues as a main protein. Type I and type III collagens were detected as major components by means of liquid chromatography–mass spectrometry analysis after digestion with trypsin. These results indicate that the triple helical collagen molecule, which is resistant to proteinase digestion, has been preserved in the soft tissues of these frozen mammoths for 40,000 years.

Unusual Myoid Differentiation in a Canine Benign Mixed Mammary Tumour

This report describes an unusual mesenchymal differentiation in a canine benign mixed mammary tumour. A 13-year-old crossbreed female dog was submitted to surgery to remove an inguinal mammary nodule. The tumour was composed of mammary epithelium and mesenchymal populations, not only of cartilage and bone but also of myoid cells. PTAH demonstrated cross striation of striated muscle, and immunohistochemistry highlighted striated muscle expressing desmin and calponin, and smooth muscle expressing desmin, SMA, and calponin. The tumour was diagnosed as a benign mixed tumour with leio- and rhabdomyoid differentiation. There was no tumour recurrence after one year of clinical follow-up. In conclusion, the well-differentiated features of leiomyocytes and rhabdomyocytes and the growth pattern define the benign origin of the mesenchymal component, which has been confirmed by a benign outcome; therefore, the knowledge of this kind of differentiation is helpful to avoid misdiagnoses.

Justification of technical parameters of an ultrasonic device for improvement of meat salting efficiency

The results of a study of the effect of wet ultrasonic lamb meat salting on the muscle tissue microstructure are presented, and the technical parameters of the ultrasonic device are justified. It has been established that significant destruction and swelling of muscle fibers, local destruction of the sarcolemma with its pronounced rugosity are observed at ultrasonic salting with a frequency of 35 kHz, the cross-striation is poorly expressed, the tissue structure is disturbed. An ultrasonic salting with a frequency of 26 kHz was accompanied an increase in the number of transverse microcracks and crevices, loosening of muscle fibers, the formation of cavities between them while retention of the tissue structure, which contributes to the appearance of a brine between muscle fibers and accelerates its penetration into the fiber. It allows us to recommend ultrasound at a frequency of 26 kHz for cavitation activation of the brine to intensify the technological process of lamb meat salting.

Congenital abnormalities and arthrogryposis in newly born lambs in Al Muthanna province Iraq. Suspicion of Akabane virus infection

Akabane virus, a member of the Orthobunyavirus genus in the family Bunyaviridae, causes congenital abnormalities and arthrogryposis with hydrocephalus or hydroencephaly in ruminants. Tis study intends to describe the clinical signs, gross and histopathological features seen in 25 afected lambs in an outbreak of congenital arthrogryposis with hydrocephalus or hydranencephaly in Al-Muthanna governorate, Iraq afer a large number of stillbirths and musculoskeletal deformities from October 2017 to May 2018. Skeletal muscle hypoplasia was seen in the limbs of the afected lambs accompanied with severe arthrogryposis and gross visible brain malformations. In addition, fetal mummifcations, stillbirths, and dead lambs were also seen. Te most histopathological features in muscle fbers were degenerative lesions and absences of cross-striation accompanied with mild infltration of neutrophils and mononuclear cells in severely afected lambs. Te meninges of afected lambs revealed fused membranes with focal areas of fbrous thickenings and necrotic debris. In conclusion, according to clinical signs, gross and histopathological investigations, Akabane virus, a member of the Orthobunyavirus genus in the family Bunyaviridae, causes congenital abnormalities and arthrogryposis with hydrocephalus or hydroencephaly in ruminants and could be the cause of this outbreak, although future studies must be performed to confrm the etiology of this outbreak. Moreover, other causes of hydrocephalus or cerebellar malformation, such as Schmallenberg virus, bluetongue virus and border disease virus and teratogenic plants that lead to arthrogryposis, have to be investigated. Also, the authorities should take prevention and control measurements to stop the replication of arthropod vectors.

TRANSFORMATION OF STRUCTURAL COMPONENTS OF MASTICATORY MUSCLES OF IMMATURE ANIMALS IN DIFFERENT STAGES OF MERCAZOLILUM-INDUCED HYPOTHYROIDISM

The aim of the study. The aim of this study was to establish the features of the structural organization of the chewing and lateral pterygoid muscles of immature rats during the developmental stages of experimental hypothyroidism. Materials and methods. The material for the study was the chewing and lateral pterygoid muscles of 48 white mongrel immature rats-males. The following research methods were used: mercazole-induced hypothyroidism modelling, injection method for studying the bloodstream, histological examination of blood vessels and tissue elements, electron microscopy, morphometric analysis, biochemical methods, statistical evaluation of the results. Results. A violation of thyroid homeostasis (a decrease in the concentration of thyroid hormones in the blood) has been established. In the bloodstream, edematous changes are observed histologically and submicroscopically. A decrease in the number of hemocapillaries per unit area and the number of hemocapillaries per muscle fiber have been established morphometrically. In muscle fibers, cross striation with vacuolization of endomysia and perimisia is lost. Edematous changes are observed, which are aggravated depending on the duration of experimental hypothyroidism. The glycolytic muscle fibers are more affected, and the changes are aggravated depending on the duration of the experiment. It has also been found out that there is a redistribution in the amount of muscle fibers. There is a tendency to a decrease in oxidative-glycolytic and a significant increase in glycolytic muscle fibers. The morphological changes that have been found out are accompanied by violations of the macroelement balance, in particular, the content of Ca, P, Mg, which determine the functioning of skeletal muscle tissue. Conclusion. Thus, at different periods of hypothyroidism, edematous changes occur both in the vascular wall and in muscle fibers, which are aggravated depending on the duration of hypothyroidism and are caused by a decrease in the basic metabolic rate, slowing of redox processes and tissue hypoxia. At the same time, chromotropic substances are released from bonds with proteins and accumulate in the intermediate substance with the subsequent replacement of collagen fibers by mucus-like masses.

Morphofunctional changes of structural components of masticatory muscles of mature animals in mercazolilum-induced hypothyroidism

The damage of the muscular system is one of the frequent complications in thyroid diseases, but today there is no unanimous view on the morphofunctional changes in masticatory muscles in hypothyroidism. The purpose of this study was to determine the peculiarities of the structural organization of the masseter and lateral pterygoid muscles of mature rats in various stages of experimentally modeled hypothyroidism. The study was performed on the masticatory muscles of mature male rats during the 14th, 21st, 28th days of the development of mercazolilum-induced hypothyroidism. The following research methods were used: injection method of study of the circulatory bed of the masticatory muscles; histological examination of blood vessels and tissue elements of the masticatory muscles; electron microscopic examination; morphometric analysis (mean value of blood vessels’ lumen and thickness of their walls; number of capillaries in 1 μm2 of cross section of muscular fiber; the quantity of the capillaries at one muscular fiber, the percentage of oxidative (OMF), oxidative-glycolytic (OGMF), glycolytic (GMF) muscular fibers, average muscular fiber area, biochemical methods, and statistical analysis was conducted out using the software RV.3.0. The development of hypothyroidism is indicated by the reduction of hormones of the thyroid gland in the blood. During the 14th day of the experiment in the arterial bed in the injection of Parisian blue in the masticatory muscles there is a deformation of the vascular pattern. The number of hemocapillaries decreases. The edema of the cytoplasm of endothelial cells is submicroscopically marked. In muscular fibers, the cross-striation is broken, the area of their cross-section is enlarged, the dilation and vacuolization are observed in the endomysium. A change was determined in the quantitative distribution of all types of fibers (the number of OGMF and OMF decreased, and the amount of GMF increased). At the ultramicroscopic level, there were observed pronounced changes in all types of muscular fibers, especially in the GMF and OMF of the masseter muscle. On the 21st day, a significant deformation of the vascular pattern was observed, with a decrease of the arterial lumen and an increase of the vein lumen. The number of hemocapillaries continues to decrease. Ultra-structurally, in the endothelial cells of the hemocapillaries of the masticatory muscles, edema changes progress. In muscular fibers there is a loss of cross-striation and observed swelling. There is a tendency to decrease of the number of OGMF and OMF and increase of the amount of GMF. At the ultramicroscopic level, there are pronounced changes in all types of fibers, especially in the masseter muscle. During the 28th day of mercazolilum-induced hypothyroidism changes in the vessels and muscle fibers are progressing. Described morphological changes are associated with the dynamics of the trace substances’ composition. Thus, in mercazolilum-induced hypothyroidism in the masticatory muscles there are edematous changes both in the vascular bed and in muscular fibers. Moreover, the changes are deepened depending on the duration of the experiment.

Study of pathological lesions in rats after the experimental administration of Lindane

In this experimental study, the lesions that are caused from the chemical substance Lindane were studied. Sixteen rats were used as experimental animals. The substance was orally administered, with food, to 10 rats (5 females and 5 males) in a dose of 8,2 mg/kg b.w./3 days during the first 10 days and in a dose of the 33 mg/kg b.w./ 2 days during the following 40 days. The remaining 6 rats (4 females and 2 males) were used as controls. The mainly clinical symptoms which were observed in the experimental animals, in the end of the experimentation, were anorexia, lethargy, hypothermia and muscular rigor. All the rats were sacrificed 5 days after the administration of the last dose of the substance and they were autopsied. In the macroscopical examination oedema and vascular hyperhaemia were observed in the brain. In the histological examination spongiosis of the white matter of the brain, interstitial pneumonia, oedema and loss of the cross striation of the cardiac muscle cells, coagulative necrosis of individual groups of hepatic cells and degeneration of the epithelial cells of the urinary tubules were detected. In conclusion, when Lindane is administered in subtoxical doses for a long period of time it is possible to cause damages to the organism of the experimental animals, which are located mainly in the brain and secondary in the liver, the kidneys and the other organs.