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1

Zmiany ultrastrukturalne w migdalkach i plucach po eksperymentalnym zakazeniu swin immunizowanych przeciw chorobie Aujeszkyego

100%
Szweda W., Przybylska-Gornowicz B.
Medycyna Weterynaryjna
|
1997
|
tom 53
|
nr 03
159-163
2

Ultrastructural study of central nervous system after experimental infection with Suid Herpesvirus-1 in pigs vaccinated against Aujeszky's disease

100%
Szweda W., Przybylska-Gornowicz B.
Archivum Veterinarium Polonicum
|
1996
|
tom 36
|
nr 1-4
3
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The low doses effect of experimental zearalenone (ZEN) intoxication on the presence of Ca2+ in selected ovarian cells from pre-pubertal bitches

100%
Gajecka M., Przybylska-Gornowicz B.
Polish Journal of Veterinary Sciences
|
2012
|
tom 15
|
nr 4
The objective of this study was to determine the effect of 42-day ZEN intoxication on the presence of Ca2+ in selected ovarian cells from beagle bitches, using the potassium pyroantimonate (PPA) method. Samples were collected from 30 clinically healthy, pre-pubertal, genetically homogeneous animals. The bitches were divided into three groups of 10 animals each: experimental group I - 50 μg ZEN/kg BW (100% NOAEL) administered once daily per os; experimental group II - 75 μg ZEN/kg BW (150% NOAEL) administered once daily per os; control group - placebo containing no ZEN administered per os. An electron microscopic analysis revealed that cells died due to apoptosis, depending on the ZEN dose and the type of cells exposed to intoxication. Lower ZEN doses led to apoptosis-like changes in the cells. Cell death was a consequence of excess Ca2+ accumulation in the mitochondria, followed by cell dysfunction and a decrease in or the absence of mitochondrial metabolic activity in oocytes, follicle cells and interstitial cells in experimental bitches.
4

Leu-enkephalin immunoreactivity in the pig pineal gland

100%
Przybylska-Gornowicz B., Lewczuk B.
Folia Histochemica et Cytobiologica
|
2002
|
tom 40
|
nr 2
5

Postnatal development of the pineal gland in the goat [Capra hircus] - light and electron microscopy studies

100%
Nowicki M., Przybylska-Gornowicz B.
Polish Journal of Veterinary Sciences
|
2006
|
tom 09
|
nr 2
This study was conducted to investigate structural transformations of the goat pineal gland during postnatal development. The pineals of newborn, 4-week-, 4-month-, 1-year- and 3-year-old male goats were prepared for qualitative and quantitative investigations at both light and transmission electron microscopy levels. In the first 4 months after birth, the pinealocytes developed very intensively, which was connected with enlargement of their volume as well as distinct qualitative and quantitative transformations of their cytoplasmic organelles. Parallel to these changes, the pineal parenchyma underwent deep reorganization and the mosaic pattern, characteristic for newborns, disappeared. At the same time the meshwork of blood vessels supporting the goat pineal gland developed conspicuously. From fourth months to one year of postnatal life continuation of the growth of some pinealocyte organelles and very intensive development of all components of the pineal connective tissue were observed. In the three-year-old goats some decrease in the relative volume of most cytoplasmic structures of pinealocytes as well as increase in collagen fibers in stroma were noticed. The investigations established intensive growth of the goat pineal to the age of 4 months, which included mainly some increase in the pinealocyte and their structures. The pineal gland of 4-month- and 1-year-old goats showed morphological features which are considered as symptoms of high secretory activity. The structure of the pineal gland in 3-year-old animals and the changes observed both in their pinealocytes and connective tissue in comparison with 1-year-old individuals point to some decrease in the goat pineal activity in this age.
6

The effect of exogenous melatonin on the pinealocyte ultrastructure in the domestic pig [Sus domesticus] depends on the time of its administration

100%
Lewczuk B., Przybylska-Gornowicz B.
Polish Journal of Veterinary Sciences
|
2000
|
tom 03
|
nr 1
Melatonin secretion is not regulated via simple negative feedback inhibition. However some results show that melatonin may influence its own synthesis and secretion as well as other processes in the pineal gland. The present study was undertaken to check the effects of melatonin administered at different times of day on the ultrastructure of pig pinealocytes. The study was performed in summer under natural photoperiod. Gilts, aged 4 months, received lmg or 3 x lmg melatonin (i.m.) daily for four consecutive days, at different times of day. Point count analysis was used in quantitative studies of pinealocyte substructures. The administration of melatonin caused clear changes in the pinealocyte ultrastructure and the effects were closely dependent on the time of hormone injection. The most visible changes were observed in pinealocytes of pigs which received one injection of melatonin per 24 hr, at the end of the light phase. This schedule of melatonin administration resulted in a decrease in the relative volume of mitochondria and dense bodies of type MBB-1 (specific structures of the pig pinealocytes) as well as an increase in the relative volume of Golgi apparatus and numerical density of multivesicular bodies. The melatonin administration three times per 24 hr (in the morning, in the early afternoon and in the evening) caused a decrease in the relative volume of mitochondria and Golgi apparatus as well as an increase in the relative volume of MBB-1. Treatment with melatonin once per 24 hr in the morning resulted in a decrease in the relative volume of mitochondria.
7

Cytoplasmic dense bodies in pig pinealocyte during postnatal development. Quantitative, ultrastructural study

100%
Przybylska-Gornowicz B., Lewczuk B.
Folia Morphologica
|
1997
|
tom 56
|
nr 1
8

The study of melatonin release from pineal gland of the domestic pig using a perfusion culture technique

81%
Lewczuk B., Przybylska-Gornowicz B., Wyrzykowski Z.
Acta Neurobiologiae Experimentalis
|
1997
|
tom 57
|
nr 5
9

Dobowe zmiany stezenia melatoniny w osoczu krwi niedojrzalych plciowo loszek podczas dlugiego dnia swietlnego

81%
Lewczuk B., Bulc M., Przybylska-Gornowicz B.
Medycyna Weterynaryjna
|
2006
|
tom 62
|
nr 10
1171-1175
The level of melatonin in plasma was investigated in gilts reared during long summer days (sunrise 430, sunset 2030). Lighting in the animal's rooms was provided by windows and fluorescent lamps, which were automatically turned on at 545 and turned off at 1945. The light intensity during photophase was 500 lux at the level of the animal's eyes. Blood samples were taken from twelve gilts over a 24 hour period and further sampling was continued in six pigs over the following 3 days. The effect of exposure to a 500 lux light during the night on plasma melatonin levels was studied in the remaining six gilts. The concentration of melatonin in the plasma was measured by direct radioimmunoassay employing an R/R/19540-16876 antibody and iodinated tracer. Concentrations of the investigated hormone were low during day and rapidly increased at the onset of night during which the plasma melatonin level remained at an elevated plateau and then declined at the onset of day. The mean concentration of plasma melatonin was about three times higher during the night compared to daytime. Monitoring of the pineal hormone level in blood plasma over four consecutive days indicated regular melatonin rhythms in 5 of the 6 investigated pigs. A 500 lux light (turned on for one night) did not prevent a nocturnal increase in plasma melatonin levels.
10
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Neuropeptide Y as a presynaptic modulator of norepinephrine release from the sympathetic nerve fibers in the pig pineal gland

81%
Ziolkowska N., Lewczuk B., Przybylska-Gornowicz B.
Polish Journal of Veterinary Sciences
|
2015
|
tom 18
|
nr 1
Norepinephrine (NE) released from the sympathetic nerve endings is the main neurotransmitter controlling melatonin synthesis in the mammalian pineal gland. Although neuropeptide Y (NPY) co-exists with NE in the pineal sympathetic nerve fibers it also occurs in a population of non-adrenergic nerve fibers located in this gland. The role of NPY in pineal physiology is still enigmatic. The present study characterizes the effect of NPY on the depolarization-evoked 3H-NE release from the pig pineal explants. The explants of the pig pineal gland were loaded with 3H-NE in the presence of pargyline and superfused with Tyrode medium. They were exposed twice to the modified Tyrode medium containing 60 mM of K+ to evoke the 3H-NE release via depolarization. NPY, specific agonists of Y1- and Y2-receptors and pharmacologically active ligands of a2-adrenoceptors were added to the medium before and during the second depolarization. The radioactivity was measured in medium fractions collected every 2 minutes during the superfusion. NPY (0.1 - 10 μM) significantly decreased the depolarization-induced 3H-NE release. Similar effect was observed after the treatment with Y2-agonist: NPY13-36, but not with Y1-agonist: [Leu31,Pro34]-NPY. The tritium overflow was lower in the explants exposed to the 5 μM NPY and 1 μM rauwolscine than to rauwolscine only. The effects of 5 μM NPY and 0.05 μM UK 14,304 on the depolarization-evoked 3H-NE release were additive. The results show that NPY is involved in the regulation of NE release from the sympathetic terminals in the pig pineal gland, inhibiting this process via Y2-receptors.
11

Abnormal morphology of skeletal muscles in meat-type chickens - ultrastructural observations

81%
Polak M., Przybylska-Gornowicz B., Faruga A.
Polish Journal of Veterinary Sciences
|
2009
|
tom 12
|
nr 4
In order to determine the effect of different production systems on muscle ultrastructure in meat-type chickens, we examined m. gastrocnemius and m. pectoralis superficialis in two lines of chickens (Anak Titan and Isa 215) raised in three different technological systems (indoors in a conventional facility, indoors with limited outdoor access and outdoors with an umbrella roof). Our previous study showed some abnormalities in the histological structure of these muscles. We hypothesized that electron microscopy, having a strategic position in muscle examination, would provide insight into changes in muscle tissue revealed by light microscopy. The results of the study indicate that the muscles examined undergo ultrastructural alterations regardless of the muscle type, chicken line and production system. The abnormalities observed in the present study were found to affect many aspects of fiber ultrastructure impairing function of the myofibrillar apparatus – the structure of mitochondria and sarcoplasmic reticulum, defects of the sarcolemma as well as the appearance of remnants resulting from fiber disintegration. Abnormal responses were found primarily in myofibrils and mitochondria, and – to a lesser extent – in other structures of muscle fibers. We suggest that the majority of the changes observed may lead to muscle damage followed by pathology. The severity of these changes was particularly evident in the muscles of chickens of the Isa 215 line (highly selected) kept outdoors with an umbrella roof. The observations point to a dependence of the above changes on the line of chickens and rearing conditions. Therefore, the limited potential of highly selected broilers to adapt to different environmental conditions should be taken into account while selecting a new production technology.
12

Wplyw warunkow utrzymania i typu uzytkowego mlodych indorow rzeznych na budowe histologiczna i ultrastrukture miesni

81%
Burs M., Przybylska-Gornowicz B., Faruga A.
Medycyna Weterynaryjna
|
2006
|
tom 62
|
nr 10
1195-1200
The study carried out morphological investigations using light and electron microscopes on the muscles of BUT 9 and Big 6 turkeys reared in two different types of conditions - indoor and outdoor (poultry yard with roof shelter). Musculus pectoralis superficialis and musculus gastrocnemius were collected from male turkeys slaughtered at 16 weeks of age. The tissues were subjected to histochemical and ultrastructure investigations, including morphometric analysis. There were no significant differences in the histology and ultrastructure characteristics of the muscles between BUT 9 and Big 6 turkeys. However, clear differences in these characteristics were observed between the two types of rearing. Degenerative changes including focal necrosis, infiltration by mononuclear cells, smaller capillary to fiber ratio and the formation of electron dense deposits, the absence of glycogen and sarcoplasm disintegration were often found in turkeys reared indoors. These structural alterations appeared to be related to partial muscle ischemia. Outdoor rearing, which enables exercise, has a beneficial effect on muscle structure.
13
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Calcium ions in the pig pineal gland - an ultracytochemical study

81%
Lewczuk B., Bulc M., Prusik M., Przybylska-Gornowicz B.
Journal of Elementology
|
2007
|
tom 12
|
nr 4
335-346
The aim of the study was to analyze the distribution of calcium ions in the pig pineal gland at the level of electron microscopy. The investigations were performed on the pineals obtained immediately after slaughter (performed between 11:30 and 12:00 a.m.) from 4-month-old gilts. The fixation procedures were conducted with the use of pyroantimonate, which reacted with calcium ions and formed electron dense precipitates. The precipitates were found both in the intercellular spaces and in cells - pinealocytes, gial cells, endothelial cells and fibroblasts. The precipitates were much more numerous in the intercellular spaces than in the cells. Amount and distribution of precipitates differed significantly between pinealocytes, therefore two types of cells were distinguished. The first type of pinealocytes included cells containing a small or moderate amount of precipitates. They were usually characterized by light or dark cytoplasm and large variability in number and structure of dense bodies. Pinealocytes classified to the second type possessed large or very large content of precipitates. These cells were characterized by electron dense cytoplasm and showed the presence of numerous dense bodies. In both types of pinealocytes, precipitates were present in the nucleus and in the cytoplasm. In nuclei, precipitates were numerous in nucleoplasma and rather infrequently noted between membranes of the nuclear envelope. In the cytoplasm deposits were found in mitochondria, vesicles and cisterns of smooth endoplasmic reticulum, in the Golgi apparatus and in cytosol. The amount of precipitates in glial cells, endothelial cells and fibrocytes was lower than in pinealocytes.
14
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Ultracytochemical localization of calcium ions in the pineal organ of the domestic turkey

81%
Lewczuk B., Prusik M., Ziolkowska N., Przybylska-Gornowicz B.
Journal of Elementology
|
2012
|
tom 17
|
nr 4
Calcium ions are involved in several processes occurring in the avian pineal, including the regulation of melatonin secretion. The aim of study was to investigate distribution of calcium ions in the pineal organ of domestic turkey at the level of electron microscopy. The study was performed on 12 female turkeys housed in a cycle of 12L : 12 D (light intensity 300 lux; 07:00 – 19:00), starting from the third week of life. At the age of 12 weeks, the birds were anesthetized with halothane and sacrificed by decapitation at 14:00 and at 02:00 (in darkness). The pineals were fixed using the potassium pyroantimonate method, which enables visualization of calcium ions in the form of electron dense precipitates. Extremely numerous, large precipitates of calcium pyroantimonate were observed between collagen fibres of the connective tissue surrounding the pineal follicles. The number of precipitates in the follicles was much lower than in the neighbouring stroma. Precipitates were numerous in intercellular spaces between cells forming the follicular wall. In contrast, they were infrequently observed in the follicular lumen. In pinealocytes, large amounts of precipitates were present in the nucleus, mitochondria and short, wide cisterns of the smooth endoplasmic reticulum. Precipitates were sparse in the apical prolongations of rudimentary-receptor pinealocytes. The content of precipitates did not differ prominently between individual pinealocytes. Precipitates in the cytosol of both rudimentary-receptor pinealocytes and secretory pinealocytes were much more numerous in the organs taken ex vivo during nighttime than during daytime. Supporting cells contained much fewer precipitates than pinealocytes.
15
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Content available

Regulation of melatonin secretion in the pineal organ of the domestic duck - an in vitro study

81%
Prusik M., Lewczuk B., Ziolkowska N., Przybylska-Gornowicz B.
Polish Journal of Veterinary Sciences
|
2015
|
tom 18
|
nr 3
The aim of study was to determine the mechanisms regulating melatonin secretion in the pineal organs of 1-day-old and 9-month-old domestic ducks. The pineals were cultured in a superfusion system under different light conditions. Additionally, some explants were treated with norepinephrine. The pineal glands of 1-day-old ducks released melatonin in a well-entrained, regular rhythm during incubation under a 12 hrs light : 12 hrs dark cycle and adjusted their secretory activity to a reversed 12 hrs dark : 12 hrs light cycle within 2 days. In contrast, the diurnal changes in melatonin secretion from the pineals of 9-month-old ducks were largely irregular and the adaptation to a reversed cycle lasted 3 days. The pineal organs of nestling and adult ducks incubated in a continuous light or darkness secreted melatonin in a circadian rhythm. The treatment with norepinephrine during photophases of a light-dark cycle resulted in: 1) a precise adjustment of melatonin secretion rhythm to the presence of this catecholamine in the culture medium, 2) a very high amplitude of the rhythm, 3) a rapid adaptation of the pineal secretory activity to a reversed light-dark cycle. The effects of norepinephrine were similar in the pineal organs of nestlings and adults. In conclusion, melatonin secretion in the duck pineal organ is controlled by three main mechanisms: the direct photoreception, the endogenous generator and the noradrenergic transmission. The efficiency of intra-pineal, photosensitivity-based regulatory mechanism is markedly lower in adult than in nestling individuals.
16

Opioid involment in the control of the pineal gland activity - a preliminary study

81%
Lewczuk B., Przybylska-Gornowicz B., Wyrzykowski Z., Kostyra E.
Acta Neurobiologiae Experimentalis
|
1996
|
tom 56
|
nr 3
17

Postnatal changes in adrenergic and neuropeptide Y - containing nerve fibres in pineal gland of the pig. An immunohistochemical study

81%
Przybylska-Gornowicz B., Kaleczyc J., Majewski M., Lewczuk B.
Folia Histochemica et Cytobiologica
|
1995
|
tom 33
|
nr 4
18

Prosomatostatin and somatostatin in pig pineal gland. An immunohistochemical study

81%
Przybylska-Gornowicz B., Lewczuk B., Moller M.
Folia Histochemica et Cytobiologica
|
1999
|
tom 37
|
nr 2
19

Distribution of NADPH-diaphorase activity in the pineal gland of the turkey

81%
Lewczuk B., Nowicki M., Brzozowski W., Przybylska-Gornowicz B.
Folia Histochemica et Cytobiologica
|
2002
|
tom 40
|
nr 2
20

Demonstration of nerve fibers immunoreactive to peptide N-terminal histidine C-terminal isoleucine [PHI] and vasoactive intestinal peptide [VIP] in the pig pineal gland

81%
Nowicki M., Lewczuk B., Papiewska M., Przybylska-Gornowicz B.
Folia Histochemica et Cytobiologica
|
2003
|
tom 41
|
nr 3
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