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1

Do environmental quality standards for selected nerve agents ensure safety of the ecosystems?

100%
Kalinowski R., Chrzanowska E., Brytan M.
Ochrona Środowiska i Zasobów Naturalnych
|
2013
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tom 24
|
nr 1(55)
2

Ocena ekotoksykologiczna wybranych bojowych środków trujących w stosunku do skorupiaków Daphnia magna

100%
Kalinowski R., Chrzanowska E., Brytan M.
Ochrona Środowiska i Zasobów Naturalnych
|
2011
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nr 48
3

Determination of PNEC for selected decontaminants based on seed germination and vigor indexes of terrestrial plants

100%
Chrzanowska E., Kalinowski R., Brytan M.
Ochrona Środowiska i Zasobów Naturalnych
|
2013
|
tom 24
|
nr 1(55)
4

Symulacja zmian aktywności acetylocholinoesterazy w przebiegu zatrucia związkami fosforoorganicznymi u ludzi z wykorzystaniem dynamicznego modelu in vitro

100%
Brytan M., Kalinowski R., Paluch M., Kowalczyk M.
Ochrona Środowiska i Zasobów Naturalnych
|
2009
|
nr 41
5

Ocena oddziaływania wojskowych odkażalników proszkowych na Lemna minor

100%
Chrzanowska E., Kalinowski R., Brytan M.
Ochrona Środowiska i Zasobów Naturalnych
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2011
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nr 48
6

Molecular mechanisms participating in inhibition of GnRH/LH secretion induced by CRH

88%
Ciechanowska M., Lapot M., Paruszewska E., Brytan M., Przekop F.
Acta Neurobiologiae Experimentalis
|
2017
|
tom 77
|
nr Suppl.1
INTRODUCTION: It is generally accepted that corticotropin-releasing hormone (CRH) is the central mediator of stress-activated changes in the pituitary-adrenal axis because it results in the release of adrenocorticotropic hormone (ACTH) and finally increases the levels of cortisol. In some situations CRH also inhibits the release of GnRH and it has been proposed as a mediator of the anti‑reproductive effects of stress. AIM(S): This study aimed to explain how prolonged activation or inhibition of CRH‑ergic activity affected molecular processes governing GnRH/LH secretion in follicular-phase sheep. METHOD(S): The study included two experimental approaches: first, we investigated the effect of CRH or CRH antagonist (α‑helical CRH 9‑41; CRH‑A) on GnRH and GnRH receptor (GnRHR) biosynthesis in the hypothalamus and on GnRHR in the anterior pituitary gland (AP) using an immunoassay (ELISA). This analysis was supplemented by radioimmunoassay (RIA) method for LH; second, we used Real-time PCR to analyse the influence of CRH and CRH‑A on the levels of kisspeptin (Kiss 1) mRNA in the preoptic area (POA) and ventromedial hypothalamus including arcuate nucleus (VMH/ARC). RESULTS: Our results show that stimulation or inhibition of CRH receptors significantly decreased or increased GnRH biosynthesis in the hypothalamus, respectively, and led to differentresponsesin the expression of GnRHR. CRH increased GnRHR abundance in the POA, but decreased it in the hypothalamus and in the AP. Blockade of CRH receptors had the opposite effect on the level of post‑translational product of GnRHR gene. In addition, administration of CRH decreased plasma LH concentration and Kiss1 mRNA in the POA and VMH/ARC, while CRH-A exerted an opposite action. CONCLUSIONS: The study demonstrates that CRH-ergic neurotransmission is involved in the regulatory pathways of GnRH and GnRHR biosynthesis in the hypothalamic-pituitary unit of follicular-phase sheep conceivably via mechanisms in which Kiss 1 participate. FINANCIAL SUPPORT: This work was supported by grant National Science Center Poland No UMO-2012/05/B/ NZ4/02443.
7

Implication of GABA-ergic system on GnRH and GnRHR biosynthesis and LH secretion in the hypothalamic-pituitary unit of follicular-phase ewes

88%
Lapot M., Brytan M., Kowalczyk M., Przekop F., Ciechanowska M.
Acta Neurobiologiae Experimentalis
|
2019
|
tom 79
|
nr Suppl.1
INTRODUCTION: An inverse relationship between GnRH transcript level and GABA neuronal activity has been suggested; in particular, that GABA at the hypothalamic level may exert a suppressive effect on subsequent steps of GnRH biosynthesis. This inhibitory action of GABA seems to be mediated mainly via a GABA type A receptor (GABAAR) mechanism. AIM(S): In the present study, we analysed the effects of GABAAR activation or inhibition on the levels of post-translational products of the genes encoding the GnRH ligand and GnRH receptor (GnRHR) in the hypothalamic-pituitary unit of follicular-phase ewes using an in vivo infusion model. METHOD(S): Prolonged intermittent infusions of small doses of the GABAAR agonist, muscimol, or an antagonist, bicuculline, were performed into the third cerebral ventricle of ewes. Enzyme‑linked immunosorbent assay (ELISA) was used to investigate the effects of drugs on GnRH and GnRHR levels in the preoptic area (POA), anterior (AH) and ventromedial (VMH) hypothalamus, stalk/median eminence (SME), and GnRHR in the anterior pituitary gland (AP). The radioimmunoassay (RIA) method was also chosen for determining the level of LH in blood plasma. RESULTS: The study showed that activation or blockade of GABAAR significantly decreased or increased, respectively, GnRH concentration in all analysed structures and led to analogous changes in plasma LH concentration. Similar muscimol‑ and bicuculline‑related alterations were observed in the levels of GnRHR. CONCLUSIONS: On the basis of these results, it is suggested that the GABAergic system in the hypothalamus of follicular-phase sheep affects GnRH and GnRHR biosynthesis either directly or via GABAergic-sensitive interneurons, leading to suppression in the secretory activity of the hypothalamic‑pituitary GnRH/LH system.
8

The role of cortisol and kisspeptin in suppression of the GnRH/LH secretion in follicular-phase ewes subjected to prolonged stress

88%
Ciechanowska M., Lapot M., Kowalczyk M., Brytan M., Przekop F.
Acta Neurobiologiae Experimentalis
|
2019
|
tom 79
|
nr Suppl.1
INTRODUCTION: A contrary relation between prolonged stress and normal reproductive efficiency has frequently been observed in domestic animals, and the action of various stressors is manifested primarily by an increase in the level of glucocorticoids in blood. AIM(S): This study aimed to determine the central and peripheral mechanisms governing GnRH biosynthesis and LH secretion in prolonged-stressed follicular‑phase sheep. They included two main experimental approaches: (1) an investigation of the effects of physical stress on GnRH and GnRH receptor (GnRHR) biosynthesis, and (2) examination of the influence of stressor on levels of mRNAs encoding kisspeptin (Kiss1) and the Kiss1 receptor (Kiss1r). Furthermore, plasma LH and cortisol concentrations were also measured. METHOD(S): The ELISA technique was used to analyse the effects of stress on levels of post-translational products of genes encoding the GnRH ligand and GnRH receptor (GnRHR) in the preoptic area (POA), anterior (AH) and ventromedial (VMH) hypothalamus, stalk/median eminence (SME), and GnRHR in the anterior pituitary (AP). Real‑time PCR was chosen for determination of the effects of stress on Kiss1 mRNA levels in the POA and the VMH the including arcuate nucleus (VMH/ARC), and on Kiss1r mRNA abundance in POA‑hypothalamic structures. These analyses were supplemented by radioimmunoassay (RIA) and ELISA methods for the measurement of LH and cortisol levels in blood, respectively. RESULTS: Stress decreased GnRH and GnRHR biosynthesis in the hypothalamus, and GnRHR in the AP. Moreover, stress lowered plasma LH concentration and levels of Kiss1 mRNA in the POA and VMH/ARC as well as Kiss1r mRNA in these structures and in the SME. An increase in plasma cortisol concentration under stress conditions was also observed. CONCLUSIONS: This study demonstrates that stress affects GnRH/GnRHR biosynthesis and LH secretion in follicular-phase sheep, conceivably via both central and peripheral mechanisms including Kiss1 neuronal activity and action of cortisol.
9

Molecular mechanisms participating in inhibition of GnRH/LH secretion induced by CRH

88%
Ciechanowska M., Lapot M., Paruszewska E., Brytan M., Przekop F.
Acta Neurobiologiae Experimentalis
|
2017
|
tom 77
|
nr Suppl.1
10

The influence of soman on the expression of tp53 gene in the rat brain; distant effect

76%
Brytan M., Kowalczyk M., Lapot M., Paruszewska E., Antkowiak B., Przekop F., Ciechanowska M.
Acta Neurobiologiae Experimentalis
|
2017
|
tom 77
|
nr Suppl.1
INTRODUCTION: The organophosphorus compound soman (GD), an irreversible inhibitor of cholinesterases, produces seizure activity and related brain damage. Studies using various biochemical markers of programmed cell death indicate apoptotic rather than necrotic mechanism of GD-induced acute cell damage in the brain. One of the most important links between the proliferation and cell death machinery is the tumor suppressor p53, which as a guardian of the genome and the element promoting apoptosis makes it a prime target for a prognostic factor. AIM(S): The aim of this study was to examine distant effects of poisoning with a small, repeated dose of GD on the expression of mRNA encoding p53 protein in the rat brain. METHOD(S): The study was performed on maternal generation (F0) and on first filial generation (F1) of Wistar rats. Low clinically asymptomatic dose of GD (0.2×LD50) was administered by subcutaneous repeated injections, first in pregnancy and subsequently during the lactation period. Six months after the end of poisoning the animals were euthanised and brain structures (hippocampus, cerebellum and piriform cortex) were isolated aseptically for evaluation of p53 mRNA. To determine p53 transcript levels Real-Time PCR with SYBR Green dye was applied. RESULTS: GD action resulted in a significant increase of p53 transcript in the cerebellum and in the piriform cortex of both F0 and F1 females as well as in F1 males. The significant elevation of p53 mRNA level in the hippocampus was observed only in F1 females. CONCLUSIONS: The study demonstrates that GD causes distant changes in the expression of p53 mRNA in the rat brain. Increased expression of p53 mRNA provides indirect evidence that GD-induced distant disorders may include DNA damage and cell cycle disturbances leading to cell dysfunction and their elimination via apoptosis. FINANCIAL SUPPORT: This work was supported by Polish Ministry of Science and Higher Education No O R00 0042 08, “Soldier as a precise weapon – individual sets and kits”.
11

Prolonged SOCS3 gene response following soman intoxication in the rat brain

76%
Paruszewska E., Lapot M., Brytan M., Antkowiak B., Kowalczyk M., Ciechanowska M.
Acta Neurobiologiae Experimentalis
|
2017
|
tom 77
|
nr Suppl.1
INTRODUCTION: In comparison with well documented data concerning the mechanisms of acute neurotoxic action of nerve agents such as soman (GD), the immunomodulatory properties of these compounds are still poorly understood, especially considering their long‑term effects. One promising candidate for mediation of GD-induced immunomodulation seems to be a suppressor of cytokine signaling 3 (SOCS 3) – an intracellular protein which exhibits a wide variety of physiological effects on immune cell function. There also exists strong evidence to support SOCS3 as a crucial regulator of many disease processes in the central nervous system. AIM(S): The aim of the present study was to determine whether perinatal exposure to GD exerted distant action on the expression of mRNA encoding SOCS3 in selected tissue of the rats brain. METHOD(S): Studies were conducted on maternal generation (F0) and on first filial generation (F1) of Wistar rats. F0 animals were treated subcutaneously with a low (0.2×LD50) repeated dose of soman (o-pinacolyl methylphosphonofluoridate). GD was administrated first, in pregnancy, and subsequently during the lactation period. Six months after termination of GD exposure animals were anesthetised and immediately hippocampus, cerebellum and piriform cortex were obtained for subsequent analysis. Real-Time PCR with SYBR Green dye was used to evaluate the level of SOCS3 mRNA in selected structures of the brain. RESULTS: Intoxication with GD decreased significantly SOCS3 mRNA levels in the cerebellum and in the piriform cortex in F0 females and in their offspring of both sexes. The analogous tendency, but without statistical significance, was observed in the hippocampus of all experimental animals. CONCLUSIONS: The current data do not clarify distant signs and symptoms of soman exposure; however, a decrease in expression of SOCS3 following intoxication with GD may suggest a functional role of this protein in pathogenesis of GD-induced neurological disorders. FINANCIAL SUPPORT: This work was supported by Polish Ministry of Science and Higher Education No O R00 0042 08, “Soldier as a precise weapon – packages and sets”.
12
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Effects of corticotropin releasing hormone and corticotropin releasing hormone antagonist on biosynthesis of gonadotropin releasing hormone and gonadotropin releasing hormone receptor in the hypothalamic-pituitary unit of follicular-phase ewes and contribution of kisspeptin

64%
Ciechanowska M., Kowalczyk M., Lapot M., Malewski T., Antkowiak B., Brytan M., Winnicka I., Przekop F.
Journal of Physiology and Pharmacology
|
2018
|
tom 69
|
nr 3
13
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Microbiological analysis of bioaerosols collected from Hospital Emergency Departments and ambulances

52%
Bielawska-Drozd A., Cieslik P., Bohacz J., Kornillowicz-Kowalska T., Zakowska D., Bartoszcze M., Wizlo-Skowronek B., Winnicka I., Brytan M., Kubiak L., Skopinska-Rozewska E., Kocik J.
Annals of Agricultural and Environmental Medicine
|
2018
|
tom 25
|
nr 2
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