Functional and morphological comparison of extracellular matrices derived from porcine small intestinal submucosa and porcine dermis to support rabbit uterus regeneration.

he aim of this study was to compare the ability of extracellular matrices (ECMs) of various structural origins to support uterus regeneration and maintain contractile function. The experiment was carried out in 18 New Zealand white female rabbits divided into a control group and two experimental groups. In the control group, bipolar electrodes were attached to the uterine horns to collect electromyography data. In the experimental groups, uterine horns were partially excised with immediate implantation of the extracellular matrix (ECM) derived from porcine small intestinal submucosa (SIS), DynaMatrix®, or from porcine dermis, Medeor® Matrix. Twelve weeks later, bipolar electrodes were attached to the regeneration areas in both experimental groups. The electromyography data in all groups were continuously recorded after administration of a single dose of estradiol valerate. Fourteen weeks after EMCs implantation, the rabbits were spayed, and the uterine wall was sampled for histological and immunohistochemical evaluation. The regenerated uterus retained the myoelectric activity pattern, and the mean amplitudes of maximum deflections did not differ between the experimental and control groups. The regeneration supported by the SIS-derived ECM was more advanced than that supported by the dermal-derived ECM. However, some pathological changes were noted in both experimental groups within the regeneration areas.

Intraocular Chondrosarcoma in a Rabbit.

Post-traumatic intraocular sarcomas are rarely reported in domestic animals and are most common in cats. An 8-year-old rabbit (Oryctolagus cuniculus) was referred to a veterinary clinic due to ocular discharge, uveitis and protein precipitate in the anterior chamber of the right eye. The eye was enucleated and histopathological examination revealed a poorly demarcated tumour within the ciliary body with invasion to adjacent eye structures. Neoplastic cells formed chaotic cartilage lacunae and were immunopositive for vimentin but immunonegative for pancytokeratin. On this basis, the neoplasm was diagnosed as a chondrosarcoma. To the best of our knowledge, this is the first report of intraocular chondrosarcoma in a rabbit. There was no history of previous ocular trauma but as there was serological evidence of Encephalitozoon cuniculi infection, inflammation could have been a predisposing factor to development of the neoplasm.

Canine and Feline Oral Cavity Tumours and Tumour-like Lesions: a Retrospective Study of 486 Cases (2015-2017).

Oral cavity tumours and tumour-like lesions are common in dogs and cats, and their diagnosis and classification requires histopathological examination. The aim of this study was to analyse retrospectively oral cavity lesions in dogs and cats in order to evaluate the distribution of inflammatory, hyperplastic and neoplastic lesions manifested as tumours. A total of 486 oral cavity tumours and tumour-like lesions (340 canine; 146 feline), diagnosed routinely from 2015 to 2017, were included. The lesions were classified as inflammatory, hyperplastic or neoplastic (benign and malignant). Histopathological diagnosis was based on haematoxylin and eosin staining and, when necessary, May-Grünwald-Giemsa (for mast cell tumours) or Masson's Fontana (for melanomas) stains or immunohistochemistry (for CD3, CD79α and S100 markers). For dogs, 29.11% (99/340) of the lesions were benign tumours, 24.12% (82/340) were hyperplastic lesions and 14.7% (50/340) were inflammatory lesions. For cats, 4.79% (7/146) were benign tumours, 15.07% (22/146) were hyperplastic lesions and 57.53% (84/146) were inflammatory lesions. Furthermore, 23.24% (79/340) of canine cases were diagnosed with gingival hyperplasia and 19.12% (65/340) were diagnosed with peripheral odontogenic fibroma, while 43.84% (64/146) of feline cases were diagnosed with chronic lymphoplasmacytic stomatitis. Malignant tumours in dogs and cats constituted 32.06% (109/340) and 21.91% (32/146) of the lesions, respectively, with high-grade melanoma in dogs and squamous cell carcinoma in cats being the most common.

Influence of simvastatin on hepatocytes - histopathological and immunohistochemical study.

The present study was undertaken to highlight the influence of simvastatin administration on hepatocyte morphology, proliferation, and apoptosis. The study included 48 gilts aged 3 months (weighing ca. 30 kg) divided into groups I (control; n=24) and II, receiving 40 mg/animal simvastatin orally (simavastatin; n=24) for 29 days. The animals were euthanized on days subsequent to the experiment. The livers were sampled, fixed, and processed routinely for histopathology, histochemistry, and immunohistochemistry (for proliferating cell nuclear antigen, Bcl-2, and caspase-3). Apoptosis was visualized by terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL). Simvastatin administration caused acute hepatocyte swelling, glycogen depletion, hyperaemia, multifocal hepatocyte proliferation with occasional pseudoacinar formation, connective tissue hyperplasia, eosinophil infiltration, and interface hepatitis. The proliferating cell nuclear antigen index, mean diameter of argyrophilic nucleolar organizer regions, and Bcl-2 immunoexpression were lower compared to control, and mean caspase-3 immunoexpression was higher in group II compared to control. On day 25 and 29 single hepatocytes in the simvastatin- treated group were TUNEL-positive. Simvastatin caused morphological alteration which became more intense over time. The results from the present study suggest that simvastatin treatment may cause glycogen, lipid metabolism and cell membrane permeability distortion, fibrosis, interface hepatitis, reduction in hepatocyte proliferation and transcriptional activity, and enhanced vulnerability to apoptosis. Summing up the results, it can be concluded that simvastatin caused liver damage with similar morphological changes seen in autoimmune-like liver injury, which may indicate that simvastatin may induce autoimmune-like drug induced liver injury.

Effects of caponisation and age on the histology of the internal organs of Leghorn cockerels.

1. Poultry researchers seek the most efficient bird line to produce capons (castrated cockerels). The previous studies did not include results from histopathological analyses of internal organs after caponisation. No data have been published on whether adipose tissue accumulates in internal organs or if caponisation changes the structure of the lymphoid organs and the accumulation of lymphoid cells. 2. The aim of this study was to analyse the occurrence of histopathological lesions in internal organs from Leghorn (layer-type) capons and cockerels at different times of fattening. 3. Two hundred, one-day-old Leghorn cockerels were used in this experiment. At 8 weeks of age, the birds were randomly divided into a control group (100 uncastrated cockerels) and a second group consisting of 100 castrated birds. At 12, 16, 20, 24 and 28 weeks of age, six cockerels and six capons were slaughtered. Samples of all internal organs from six cockerels and six capons at each slaughter age were evaluated. 4. The main histopathological differences between capons and cockerels were related to the accumulation of adipose tissue, with higher values noted in capons, especially in the gizzard and the caecum submucosa and fatty degeneration in liver hepatocytes. 5. Additionally, differences were observed more often in cockerels than in capons with regard to depletion of lymphoid cells in lymphoid organs, including the thymus and bursa of Fabricius in 28-week-old birds and the spleen in 24-week-old birds. 6. These studies prove that caponisation causes the accumulation of fat in internal organs and changes the structure of lymphoid organs. 7. Age influences the occurrence of desirable lesions, such as the accumulation of adipose tissue within the examined organs, and older capons (24 and 28 weeks old) are better sources of high quality, potentially edible tissues.

Influence of simvastatin on red blood cell line in porcine bone marrow.

Simvastatin is a drug commonly used to reduce the cholesterol level. 32 clinically healthy female pigs with a bodyweight of 35-40 kg, kept in standard laboratory conditions were chosen for the experiment and divided into 2 groups (control and experimental) consisting of 16 animals. The experimental group received simvastatin orally at a dose of 40 mg (one tablet once a day) for 56 days, and at the same time the control group received placebo (empty gelatin capsules). Bone marrow smears and peripheral blood samples were evaluated. The obtained results indicate that simvastatin may inhibit erythropoiesis even after a relatively short period of administration, and observed changes can be the cause of some symptoms (for example anemia) occurring during statin therapy.

Morphology and immunoreactivity of canine and feline extramedullary plasmacytomas.

The aim of the study was the evaluation of morphology and immunophenotype of canine (19 cases) and feline (7 cases) extramedullary plasmacytomas. Tumours, located in skin, oral cavity and spleen were surgically excised, fixed and processed for histopathology and immunohistochemistry (CD79α, CD18, proliferating cell nuclear antigen, metallothionein). Histologically, tumours were classified into mature, cleaved, asynchronous, polymorphous blastic, hyalin, or monomorphous blastic type. All evaluated tumours showed cytoplasmic expression of CD79α antigen. The expression of CD18 was observed in canine cutaneous and splenic tumours. In canine tumours expression of metallothionein was low to moderate, while in feline plasmacytomas - absent or low. In canine tumours, the mitotic index and proliferating cell nuclear antigen index were positively correlated with the expression of metallothionein. In feline tumours no correlation between mitotic index, proliferating cell nuclear antigen and metallothionein was found. This is the first study describing expression of metallothionein in canine and feline extramedullary plasmacytoma.

Safety of the long-term application of QuikClot Combat Gauze, ChitoGauze PRO and Celox Gauze in a femoral artery injury model in swine - a preliminary study.

The purpose of this study was to examine the safety of the long-term application of QuikClot Combat Gauze, ChitoGauze PRO and Celox Gauze using a swine model. The study was conducted on nine pigs weighing approximately 30 kg, which were randomly divided into three groups. Under deep anesthesia, the pigs underwent complete transverse cutting of the femoral artery in the groin region. Hemostatic dressings were left in the wound for 24 hours. The animals were euthanized 24 hours after dressing application. In each group, macroscopic and microscopic severe changes and shock symptoms were observed in the lungs, liver, kidneys and heart. Fibrino-gaseous embolic material was found in the pulmonary artery of each group and in the lung vessels of the animals from the ChitoGauze PRO and Celox Gauze groups. In conclusion, the long-term application of the evaluated hemostatic dressings has the risk of coagulopathy and reaching the progressive stage of shock. The residues from the hemostatic dressings can ingress into the systemic circulation, thereby increasing the risk of embolus formation. Because of these harmful effects, the evaluated hemostatic dressings are not appropriate for long-term use. Future studies are needed on the consequences of the long-term application of these hemostatic agents.

Histopathological studies of the heart in three lines of broiler chickens.

The aim of this study was to analyse the morphological lesion pattern of the heart of broiler chickens (Cobb 500, Hubbard F15 and Ross 308) during fattening with no clinical signs of disease and to determine the most susceptible period for the occurrence of morphological lesions. The most frequently diagnosed lesions in each genetic line were degeneration of the fibres with vacuolation, congestion of cardiac muscle, oedema and vacuolisation of the Purkinje cells. The highest numbers of morphological lesions were observed on d 38, 31 and 10 of life. The lesions were most numerous in the septum, followed by the left and right ventricles. Ischaemic cardiomyocytes were also most numerous on d 38 of life and in the left ventricle. Overload of cardiac muscle, prolonged hypoxia and increasing body weight on d 38 are the likely reasons for the largest number of lesions and ischaemic fibres, which may lead to heart failure.

Effect of low-energy laser irradiation and antioxidant supplementation on cell apoptosis during skeletal muscle post-injury regeneration in pigs.

The aim of this study was to evaluate the effect of low-energy laser irradiation, coenzyme Q10 and vitamin E supplementation on the apoptosis of macrophages and muscle precursor cells during skeletal muscle regeneration after bupivacaine-induced injury. The experiment was conducted on 75 gilts, divided into 5 experimental groups: I--control, II--low-energy laser irradiation, III--coenzyme Q10, IV--coenzyme Q10 and vitamin E, V--vitamin E. Muscle necrosis was induced by injection of 0.5% bupivacaine hydrochloride. The animals were euthanized on subsequent days after injury. Samples were formalin fixed and processed routinely for histopathology. Apoptosis was detected using the TUNEL method. The obtained results indicate that low-energy laser irradiation has a beneficial effect on macrophages and muscle precursor cell activity during muscle post-injury regeneration and protects these cells against apoptosis. Vitamin E has a slightly lower protective effect, limited mainly to the macrophages. Coenzyme Q10 co-supplemented with vitamin E increases the activity of macrophages and muscle precursor cells, myotube and young muscle formation. Importantly, muscle precursor cells seem to be more sensitive to apoptosis than macrophages in the environment of regenerating damaged muscle.

Aggressive, solid variant of alveolar rhabdomyosarcoma with cutaneous involvement in a juvenile labrador retriever.

An 8.5-month-old male Labrador retriever presented with a cutaneous mass in the right maxillofacial region and swelling of the gingiva. The dog received antibiotic and anti-inflammatory treatment. After 3 weeks the dog returned, presenting with disseminated cutaneous tumours on the neck, trunk and groin. One of the nodules was resected and a cutaneous round cell tumour was diagnosed on microscopical examination. The dog was humanely destroyed. Necropsy examination revealed disseminated tumours in the skin, internal organs and skeletal muscles. Microscopically, all of the tumours were composed of small round cells, arranged in nests. Immunohistochemically, the neoplastic cells expressed vimentin, desmin, MyoD1, myogenin and smooth muscle actin, but were negative for CD3, CD18, CD79αcy, cytokeratin AE1/AE3, chromogranin A, class II molecules of the major histocompatibility complex, neuron-specific enolase and S100. The average Ki67 index was 89.5%. The final diagnosis was a solid variant of alveolar rhabdomyosarcoma (ARMS). This is the first report of the cutaneous multifocal form of ARMS in veterinary oncology.

Cytomorphometry of canine cutaneous histiocytoma.

A morphometric analysis of tumoral Langerhans cells and activated macrophages was conducted using canine cutaneous tumors (65 cases of canine cutaneous histiocytoma and 7 cases of pyogranuloma). The histiocytic origin of the tumor cells was confirmed using immunohistochemistry. The parameters of the morphometric analysis included cellular and nuclear size and shape and the nuclear:cytoplasmic ratio; the variability of these features was calculated separately for each tumor. The canine cutaneous histiocytoma group was divided into four stages of regression depending on the intensity of the lymphocytic infiltration. Statistical analysis revealed that the anisocytosis, anisokaryosis and cellular pleomorphism of tumoral Langerhans cells increased, while the cellular circularity and nuclear:cytoplasmic ratio decreased with tumor regression. Activated macrophages of the pyogranuloma were significantly larger, and had larger nuclei, than tumoral Langerhans cells. Furthermore, these activated macrophages showed greater anisocytosis and anisokaryosis and a lower nuclear:cytoplasmic ratio than tumoral Langerhans cells in the first stages of tumor regression. These results indicate that tumoral Langerhans cells undergo morphologic changes during the regression of canine cutaneous histiocytoma, reflecting their maturation and differentiation. Morphometry can be a useful method for distinguishing activated macrophages from tumoral Langerhans cells.

Effect of 24 hour application of three hemostatic dressings to porcine thigh muscles.

The effectiveness of three types of hemostatic dressings, QuikClot Gauze, ChitoGauze PRO and Celox Gauze, was evaluated in nine pigs. The results indicated a strong influence of all examined dressings on porcine femoral muscle tissue evaluated 24 hours after direct contact. A histopathological analysis revealed pathological changes in muscle tissue specimens collected from all the animals.

Immunocytochemical expression of 3beta- and 17beta-hydroxysteroid dehydrogenase in bitch ovaries exposed to low doses of zearalenone.

Companion animals, including bitches, are exposed to intoxication with zearalenone (ZEN) present in feed, and the above may lead to reproductive disorders which are pften noted in veterinary practice. The aim of this study was to determine the effect of long-term and low-dose ZEN intoxication on the immunoexpression (optical density) of 3beta-hydroxysteroid dehydrogenase (3beta-HSD) and 17beta-hydroxysteroid dehydrogenase (17beta-HSD) in the ovaries of pre-pubertal bitches. The experiment involved 30 clinically healthy, immature Beagle bitches aged approximately 70 days with initial average body weight of 8 kg. The animals were randomly divided into two experimental groups (EI and EII) and a control group (C; n = 10 in all groups). Group EI was administered 50 microg ZEN/kg BW per os over a period of 42 days, group EII received 75 microg ZEN/kg BW per os for 42 days, and group C was administered placebo per os over a period of 42 days. Weighed amounts of the analyzed mycotoxin were administered every morning in gel capsules before feeding. The animals were subjected to ovariohysterectomy at the end of the experiment. Immunocytochemical analyses were performed to localize 3beta-HSD and 17beta-HSD enzymes and determine their optical density. The results revealed that changes in the immunoexpression of the above enzymes were inversely proportional to the applied dose of ZEN substrate.

Fibromuscular dysplasia in arteries and in a vein in broiler chickens.

Fibromuscular dysplasia (FMD) is a group of nonatherosclerotic, noninflammatory diseases of blood vessels with unknown aetiology. In our study, FMD was diagnosed in blood vessels in samples taken from kidneys, liver and lung of broiler chickens. The FMD occurred during rearing in 8 of 108 broiler chickens examined for the effects of intensive rearing on the.internal organs. Histopathological and immunohistochemical examinations revealed medial subtypes of FMD, medial fibromuscular dysplasia and medial fibromuscular stenosis. The first subtype presented as plugs in vessel lumens consisting of smooth muscle and fibrous connective tissue originating from the tunica media. The second subtype presented as a proliferation of smooth muscle cells and fibroblasts originating from the media and leading to lumen stenosis. The aetiology of FMD is still unknown. Thus, genetic factors are suspected as a cause of the disease. This is the first report of FMD in a vein of an animal species.

Sensitivity of skeletal muscle to pro-apoptotic factors.

In mononuclear cells, apoptosis leads to DNA fragmentation and cell destruction, regardless of the activated pathway. As regards multinuclear cells, e.g. skeletal muscle fibers, apoptosis rarely induces the death of the entire cell, and it generally affects single nuclei. This process, referred to as nuclear apoptosis, has a negative effect on the expression of genes in the myonuclear domain. Apoptosis may be initiated in muscle cells by external stimuli which activate cell membrane death receptors as well as by internal stimuli which stimulate the mitochondrial release of pro-apoptotic proteins. Reactive oxygen species also play an important role in the initiation of apoptosis. In muscle cells, ROS are produced in response to extracellular reactions or by cell mitochondria. It is, therefore, believed that mitochondria play a central role in apoptosis within skeletal muscle. Skeletal muscles have a well-developed system that protects them against oxidative damage. Myogenic stem cells are an integral part of multinucleated myofibers, and they are critically important for the maintenance of normal muscle mass, muscle growth, regeneration and hypertrophy. The latest research results indicate that myogenic cells are more sensitive to oxidative stress and pro-apoptotic factors than well-differentiated cells, such as myotubes. The complex structure and activity of skeletal muscle prompted research into the role of apoptosis and its intensity under various physiological and pathological conditions. This review summarizes the results of research investigating control mechanisms and the apoptosis process in skeletal muscle fibers, and indicates unresearched areas where further work is required.

The influence of experimental Yersinia enterocolitica infection on the pregnancy course in sows--preliminary studies. III. Histopathological lesions.

The aim of the study was to evaluate the anatomo- and histopathological lesions in internal organs of sows and their stillborn piglets after experimental Y. enterocolitica infection in different phases of pregnancy. Twelve pregnant sows were divided into 4 groups, infected per os on 33 (n = 3), 54 (n = 3) and 89 (n = 3) day of pregnancy with the pathogenic Y. enterocolitica strain isolated from the aborted swine fetus, and uninfected control group. Histopathological examinations of internal organs and intestine samples of stillborn piglets, slaughtered sows and samples of placentas were performed. Anatomo- and histopathological lesions were the most intense in the group of sows infected in the final phase of pregnancy, where the highest number of stillborn piglets was also found. Lesions of internal organs in stillborn piglets suggested a severe generalized bacterial infection. Although the analysis of experimental Y. enterocolitica infection of pregnant sows revealed that the most intense clinical, anatomopathological and histopathological abnormalities were recorded in the group of animals infected in the final phase of pregnancy. Infection in the first phase of pregnancy could have had an influence on the formation of the granulomatous inflammation. Differences in anatomopathological lesions between infected and control animals suggest that the period of pregnancy in which the infection appears could have had an influence on the course of yersiniosis in pigs.

Effect of butaphosphane and cyanocobalamin on regeneration of muscle fibres in pigs.

The aim of the study was to monitor the effect of butaphosphane (1-(n-butylamino)-1-methylophosphorous acid) and cyanocobalamin (Catosal preparation, Bayer AG) on regeneration of the longissimus lumborum muscle (musculus longissimus lumborum) in pigs. Experiments were conducted on 34 piglets of Polish Large White breed with a mean body weight of 20 kg that were divided into two groups. Piglets of group I (control) received an intramuscular injection of 10 cm3 of 0.5% bupivacaine hydrochloride at both side of the spine. Piglets of group II were injected with bupivacaine, as in group I, and additionally received intramuscular injections of 5 ml of Catosal for 5 subsequent days. The animals were euthanized 6, 12, and 24 hours as well as 2, 3, 4, 5, 7, 10 and 14 days after muscle injury. Preparations obtained from muscle specimens were stained with HE, PAS method acc. to McManus, HBFP, Feulgen, and Unna methods. Ultrastructural preparations (TEM) were prepared following a standard procedure. The presence of vimentin, desmin and PCNA was detected immunohistochemically in sections prepared with a paraffin method. Necrosis of muscle fibres was observed in all animals after bupivacaine injection. The administration of Catosal accelerated the regeneration of damaged skeletal muscles in pigs through the facilitation of phagocytosis and enhancement of myogenic cells proliferation. No effect of Catosal was found on differentiation of myoblasts or maturation of newly-formed muscle fibres.

Histopathological and immunohistochemical examinations, and changes in proliferation activity of the uterus in bitches following zearalenon micotoxicosis.

The research was aimed at determining the impact of the experimental oral administration of zearalenon on the uterus in bitches. The study was carried out on 9 sexually mature 1 to 3 year-old bitches that were divided into three groups: two experimental ones and a control group. The experimental animals were orally administered zearalenon at 25 microg/kg BW (body weight) (group DI; n=3) and 50 microg/kg BW (group DII; n=3) throughout 100 days while the control bitches (group K; n=3) were administered placebo. After the period of 100 days, ovariohysterectomy was performed, and the uterine samples were submitted to histopathological and immunohistochemical examinations in order to determine the structure of the wall and the presence of PCNA antigen. In the experimental animals, the histopathological examinations revealed regressive lesions, such as degeneration and atrophia within the endometrium and myometrium, and local circulatory disorders, i.e. edema and extravasation. These lesions were not reported in the controls. In the bitches administered zearalenon, the tissues did not express any proliferative activity as determined by the presence of PCNA. It is assumed that, following the administration of zearalenon for 100 days orally to bitches, disruption of the structures within the wall of the uterus (i.e. degeneration, atrophy, edema, and extravasation within the endometrium and myometrium) develops. This research proves that zearalenon ingested by bitches may lead to dysfunction of the uterus and cause disruption of its structures.

Effect of melatonin implants on the morphological picture of selected internal organs, and hematological and biochemical indices in minks.

This study was aimed at monitoring the effect of melatonin implants on selected hematological and biochemical indices as well as on morphology changes of lungs, liver, spleen, kidneys and brain in minks. Experiments were carried out on 300 minks aged 2 years, bred under conditions of a large-herd farm and fed identical feedstuff. Melatonin implants were inserted subcutaneously to the minks in the form of granules containing 6 mg of melatonin. The control group consisted of minks from the basic herd. A better appetite and higher body weights characterized the experimental minks. Skins obtained were larger, thinner and covered with springy hair with a good sheen, yet were stragglier than in the control group. The hematological indices analyzed did not differ between the groups and were within referential values. Biochemical indices of liver and kidneys profiles were better in the experimental group. In the experimental minks, histopathological examinations demonstrated lesser intensity of disorders in brain and liver circulation, lesser intensity of degenerative lesions in liver tissues and kidneys as well as smaller infiltration of lymphocytic and plasmatic cells in lungs and liver.