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B Jana

Publications and source records attributed to B Jana.

14 recordsLinked to original sources
PubMed2006

Why does ethanol induce cellular heat-shock response?

At the time of induction of the periplasmic protein alkaline phosphatase (AP) in Escherichia coli, the presence of ethanol (10% v/v) in the growth medium did not allow the induced AP to be translocated out to the periplasm. The nontransported AP was stored in the cytoplasm as the unfolded precursor form (AP with its amino-terminal signal sequence), which had no enzymatic activity. The presence of 10% v/v ethanol in the growth medium also induced the heat-shock response in E. coli, which was evident from the enhanced syntheses of several heat-shock proteins (HSPs) over their cellular basal levels. These results, in conjunction with our earlier findings on the occurrence of heat-shock response in an AP-signal sequence mutant of E. coli due to the export deficiency of AP precursor, suggest that the membrane protein precursors, stored in the cytoplasm due to the ethanol-mediated inhibition of translocation, behaved to the cells as abnormal proteins, which ultimately triggered the signal for the induction of heat-shock response in E. coli.

Alkaline Phosphatase↗
PubMed2006

The impact of zearalenone on the level of the selected estrogens in blood serum of sexually immature gilts.

The aim of the study was to evaluate the influence of low dose (LOEL - lowest observed effect level) of zearalenone (200 microg/kg b.w.), applied per os for 7 days (short-term intoxication), on sexual behavior, concentration of the examined xenobiotic and its metabolite and selected estrogens in sexually immature gilts: ovariohysterectomised (group D1) and intact (group D2) animals. Clinical signs of oestrus (reddening, oedema and hyperaemia of the vulva and serorhoea from the reproductive tract--lack of standing reflex) were obserwed in group D1 on day 6 and in group D2 on day 4 of the experiment. Laboratory analyses of blood plasma were carried out determine the presence of zearalenone and alpha-zearalenole. They revealed an increase in the level of alpha-zearalenol before the oestrus, decrease in total amount of both examined substances on day when the oestrus appeared and increase in the level of both examined xenobiotics in the post oestrus period together with the higher share of zearalenone. Medium concentrations of estrone and estradiol within the borders of method determination in the majority of periods examined. Higher levels of estrone (32.0 pg/ml) were found on day 4, in the group D2 and estradiol (6.5 pg/ml) on day 6 in the D2 group. The presents study revealed that zearalenone applied per os at LOEL dose causes the incidence of apparent sexual readiness (without standing reflex) in sexually immature gilts with the somatically immature reproductive system.

Animals↗
PubMed2005

Level of zearalenone in blood serum and lesions in ovarian follicles of sexually immature gilts in the course of zearalenone micotoxicosis.

The aim of the study was to determine how a low dose of zearalenone applied orally for eight days influences the level of zearalenone (ZEN) and alpha-zearalenole in blood plasma and causes the occurrence of histopathological changes in the cells of the ovarian follicles in sexually immature gilts. The animals were divided into 2 groups (control, C; n = 4 and experimental, E; n = 4). The gilts from group E were treated daily with zearalenone at a dose of 200 microg/kg b.w. The level of zearalenone and alpha-zearalenole (ZON as the sum of the levels of both zearalenone and alpha-zearalenole) was measured daily. On day eight of the experiment the animals were sacrificed and their ovaries were taken for histopathological examination. The tissue sections obtained were HE- and PAS-stained according to McManus. The presence of PCNA antigen was also estimated. The highest concentration of ZON was noted on day 5 in group E (8.16 +/- 2.49 ng/ml). External estrus symptoms without standing reflex were observed in group E on day 4. In group C there were no pathological changes in the ovaries. In group E, a few ovarian follicles were found, but they were located in the cortical layer. They were filled with a liquid substance rich in protein and without the granulosa layer. There was disintegration with apoptotic-like changes of the PCNA-negative cells in the granulosa layer of single mature follicles. On day 4 the dose of zearalenone caused disturbances in the process of development and maturation of some of the best developed ovarian follicles. This probably occurred through the activation of on apoptosis-like process of the granulosa cells with simultaneous manifestation of estrus without standing reflex.

Animals↗
PubMed2005

Immuno-endocrine mechanisms connected with the creation of corpora lutea persistent in animal ovaries.

Factors which induce the corpus luteum persistent (CLP) creation in animal ovaries are located in the hypothalamic-pituitary-ovarian axis and also in the uterus. In cows and likewise in others animals, various mediators of inflammatory reaction are released, mainly proinflammatory cytokines from inflamed uterus into the blood and lymph. Afterwards the cytokines cross the blood-brain barrier, and though the brain mediators alter the hormonal profile and amplitude pulses of the hormones release in the hypothalamus and the pituitary. Until it is known, that cytokines: IL-1, IL-2, IL-6, TNF-alpha and also IFN-alpha, administered into the median eminence, cause an increase in corticotrophin-releasing hormone (CRH) and adrenocorticotropic hormone (ACTH) concentrations and decrease in the pituitary gland hormones secretion. The immune system, represented in the corpora lutea (CL) by numerous macrophages/monocytes, limphocytes and neutrophils plays an important role in the luteolysis process. The stimulating factor of the infiltration of these cells is an increased PRL level. The preovulatory increase in PRL level regulates the number of macrophages in newly-formed CL and later influences the number of these cells in the luteolysis period. The pulsatory release and high levels of the hypophyseal oxytocin (OT) and uterine PGF2alpha ensure the beginning and the normal course of the luteolysis period. The cytokines decrease OT concentration and disorder its pulsatory release from the pituitary. In these circumstances the quantity of the uterine PGF2alpha reaching ovaries, is insufficient to begin luteolysis. In the inflamed uterus, the elevation of PGE2 and PGI2 synthesis takes place. Both prostaglandins cause smooth uterine muscles relaxation and the dilatation of blood and lymph vessels in this organ. In these conditions, the blood and lymph outflow from the uterus is several times slower than in the control animals. The secretion of P4 and E2 from CLP, in comparison with control animals, is significantly lower. Decreased P4 concentration during the luteal phase of the estrous cycle, and E2 in the initiation of the luteolysis period, may cause the insufficient preparation of the endometrium for hypophyseal OT activity. Finally, we can assume that the creation of the CLP in the animal ovary is an exceptionally complex and not yet fully understood process.

Animals↗
PubMed2005

The effect of intrauterine infusion of inflammation-provoking factors on proinflammatory cytokines and hormones in rat peripheral blood.

The aim of the study was to determine, using the rat model, whether uterine infections cause an increase in cytokine concentrations in peripheral blood, and whether this increase is accompanied by changes in the pituitary-ovarian axis function. The levels of tumor necrosis factor-alpha, interleukin-1beta, luteinizing hormone, follicle-stimulating hormone, prolactin, progesterone, testosterone and estradiol-17beta in blood plasma as well as the weight of the uterus were determined after intrauterine infusion of lipopolysaccharide (15 microg), peptidoglycan (1 mg) and Escherichia coli (10(6) cfu) suspension on the day of metaestrus. On days 3, 7 and 10 after treatment the rats were sacrificed to collect the blood samples. Inflammation of uterus and vaginal discharge developed in all rats after treatment. The administration of lipopolysaccharide, peptidoglycan and Escherichia coli induced considerable changes in ovarian cyclic activity, mainly diestrus was observed. Application of all these factors resulted in an increase (P<0.05, P<0.01) of plasma levels of tumor necrosis factor-alpha, interleukin-1beta, mainly on day 3 and 7. In the rats receiving pathological factors, the plasma levels of luteinizing hormone, follicle-stimulating hormone, prolactin and estradiol-17beta decreased (P<0.05, P<0.01) whereas progesterone and testosterone increased (P<0.05). These results indicate that in rats, the developing inflammatory process of the uterus following lipopolysaccharide, peptidoglycan and Escherichia coli infusions is connected with an increase of tumor necrosis factor-alpha, interleukin-1beta concentrations in peripheral blood, and is accompanied by changes in the pituitary-ovarian axis function.

Animals↗
PubMed2004

Adrenergic innervation and steroidogenic activity of cystic porcine ovaries.

We studied both morphology and steroidogenic activity of porcine ovaries after dexamethasone (DMX)-induced polycystic status. In the polycystic-changed ovaries, an increase in the number of DbetaH-IR and/or NPY-IR nerve terminals was found in the wall of follicles, cysts and blood vessels. After DXM injections, we observed changes in the mean contents of progesterone, androstendione, estradiol-17beta, as well as noradrenaline, dopamine and adrenaline in the studied ovarian structures. The obtained data revealed that, in the polycystic ovaries of gilts, an increase in the number of adrenergic nerve terminals was associated with changes of the steroidogenic activity, what may suggest an important role of the adrenergic innervation in the ovarian cyst formation in the gilts.

Analysis of Variance↗
PubMed2003

Targeted destruction of normal and cancer cells through lutropin/choriogonadotropin receptors using Hecate-betaCG conjugate.

A recent approach to cancer treatment is destruction of malignant and non-malignant tumors by hormonally targeted lytic peptides. The presence of lutropin/choriogonadotropin (LH/CG) receptors has been confirmed in several cancer cells (e.g. breast, ovarian, and prostate). In a series of experiments conducted in vitro, we have used a conjugate of the 23-amino acid lytic peptide Hecate and a 15-amino acid segment of beta-chain of CG. To test the hypothesis that Hecate-betaCG selectively destroys porcine granulosa and luteal cells, and Leydig cancer cell line (BLT-1) possessing LH/CG receptors, the conjugate was added to culture media at different concentrations of 0.5 to 10 micro M. Spleen cells and late passage of granulosa cancer cell line (KK-1) not-possessing LH/CG receptors were used as controls. The toxicity of Hecate-betaCG conjugate was concentration-dependent in all cell types but different among various cells. The toxicity of the conjugate to treated cells was closely correlated with the number of LH/CG receptors per cell. At low concentration (1 micro M), Hecate-betaCG was more cytotoxic to cells bearing LH/CG receptors than to controls (p < 0.01). In contrast to cells possessing LH/CG receptors, cancer cell line KK-1 and spleen cells were sensitive only at concentration of 5 micro M (p < 0.001). We conclude that Hecate-betaCG selectively kills cells expressing LH/CG receptors; its toxicity is dependent on the number of binding sites for LH/CG.

Animals↗
PubMed2003

The cannulation of the caudal caval vein through the femoral vein in the pig for endocrine research.

The present study was designed to examine the usefulness of cannulation of the caudal caval vein through the femoral vein for the measurement of hormone concentrations in the reproductive tract in the pig. The experiment was performed on sexually pubertal gilts (Polish Large White x Polish Landrace) of a similar age (7-8 months) and body mass (100-110 kg) after two controlled subsequent estrous cycles. Six gilts in the luteal phase (10th day) of the estrous cycle were used in this experiment. The animals were subjected to a surgical procedure which included:--premedication (Combelen, i.m. 1 ml/10 kg of body mass) and than after 20-30 min general anaesthesia (Vetbutal, i.v., dose 30-40 ml) according to body mass and the symptoms observed,--insertion of cannulas (o.d. 2.2 and i.d. 1.8 mm)--one into the jugular vein and the other into the caudal caval vein through the femoral vein. In several gilts the cannulas were inserted into the caudal caval vein to a depth of 14, 18, 20, 23, 25 and 30 cm from the femoral ring. The concentrations of progesterone (P4) and testosterone (T) were analysed in samples of blood plasma from the jugular and caudal caval veins by radioimmunoassay (RIA). The largest differences in hormone concentrations between the jugular and caudal caval veins were ascertained when a cannula was inserted into the caudal caval vein to a depth of 20 cm from the femoral ring. In other cases the differences were less prominent, or no differences were observed (e.g. 14 cm for progesterone and testosterone or 18 cm for testosterone).

Animals↗
PubMed2002

Hormonal profile and morphological changes in pig ovaries after intraovarian infusions of Escherichia coli endotoxin.

The purpose of this study was to estimate morphological changes in the ovary and size of the production of steroid hormones during the luteal phase of the estrous cycle in pigs after intraovarian infusions of Escherichia coli endotoxin. Polish Large White gilts (n = 15) of similar age (7-8 months) and body weight (90-110 kg) with two controlled subsequent estrous cycles were used. The animals were randomly divided into two groups: control (n = 9, the 10th day of the estrous cycle,) and treated with Escherichia coli endotoxin (n = 6, the same day of the estrous cycle). The gilts were infused with Escherichia coli endotoxin at a dose of 1 mg three times a day during six consecutive days, from the 14th to the 19th day of the estrous cycle. Plasma concentrations of progesterone (P4), androstenedione (A4), testosterone (T), estrone (E1) and estradiol-17 beta (E2) were determined by radioimmunoassay method. Infusions of Escherichia coli endotoxin resulted in a significant (p < 0.001) decrease in the production of P4, A4, T, E1 and E2 in the luteal phase as compared with the levels found in the control animals. Plasma level of P4, A4 and T was decreased by 84.6%, 86.0% and 73.0%, respectively. Plasma concentrations of E1 and E2 in some cases exceeded 5 pg/ml, nevertheless in the majority of the samples they were under sensitivity of the method. Escherichia coli endotoxin infusions resulted in a considerable decrease in the size of the ovaries, and morphological changes characteristic for acute and chronic inflammation were observed.

Androstenedione↗
PubMed2002

Effect of the gonadotrophins treatment on morphological alterations in ovary and peripheral plasma concentrations of steroid hormones in gilts.

The present study was designed to examine the influence of gonadotrophins treatment on the ovarian morphology changes and plasma concentrations of steroid hormones in peripheral blood. The experiment was performed on sexually pubertal gilts (Large White x Landrace) of similar age (7-8 months) and body mass (100-110 kg) with two controlled subsequent estrous cycles. The animals were randomly divided into four groups: two control consisting of pigs with the luteal phase (n = 9, the 10th day of the estrous cycle) and the follicular phase (n = 6, the 20th day of the estrous cycle) and two experimental ones consisting of animals with both mentioned periods (n = 7 and n = 9) treated with gonadotrophins (PMSG and hCG). The gilts in the luteal phase were injected (s.c.) with gonadotrophins at a daily dose of PMSG 400 and hCG 200 IU from the 16th to the 27th day (the 6th day of the next estrous cycle). The gilts in the follicular phase, were injected with the same dose of gonadotrophins but from the 8th to the 19th day of the estrous cycle. Plasma concentrations of P4, A4, T, E1, E2 and metabolite of PGF2 alpha-PGFM were determined by radioimmunoassay (RIA) method. Injections of PMSG and hCG in both experimental groups produced several times enlarged: weight, size and volume of ovaries and alterations in a number of structural elements as compared with those found in the control animals. The morphological elements presented in ovaries: corpora haemorrhagica, corpora lutea, regular and atretic follicles and first of all cysts by distinctly differentiation thickness of the walls are characteristic for cystic ovarian degeneration. Plasma concentrations all determined hormones after gonadotrophins treatment in experimental groups were increased except E1 (insignificant decrease) in luteal phase as compared with those found in the control groups. Statistically significant increase (p < 0.001) in plasma concentrations of P4, A4, and T in both experimental groups and E2 (p < 0.001) in luteal phase were noted. In peripheral plasma concentrations increase of E1 and E2 in follicular phase of the estrous cycle were insignificant.

Animals↗
PubMed2002

Boar pheromone androstenol may affect the ovarian morphology in cycling gilts by humoral pathway.

Up to 1999 it was accepted that pheromones act exclusively by stimulation of dendritic receptors of olfactory neurons massed in the olfactory epithelium, but in 1999-2000, the presence of local humoral pathway for transfer of boar pheromone androstenol from the nasal cavity to the hypophysis and brain was demonstrated in gilts. The aim of the present study was to ascertain whether boar pheromone androstenol may affect by humoral pathway the ovarian morphology in gilts. This study demonstrated that intramuscular injections of androstenol in the follicular phase (17-20 day) of the estrous cycle in anosmatic gilts, in which the neural pathway for olfactory function was experimentally blocked, produced lack of the ovulation and changes in the morphology of ovaries. Histological analysis of the ovaries, collected seven days after androstenol injections, revealed the absence of corpora lutea and healthy follicles of a diameter over 6 mm as well as a significant decrease in the number of the follicles up to I mm in diameter (P<0.01). In androstenol-treated gilts, the number of atretic follicles from 1 mm to 6 mm in size was increased (P<0.01-P<0.001) and in one gilt cysts were found. The obtained results provided some evidence that in gilts in addition to acting by standard neural pathway, androstenol as a priming pheromone may affect the ovarian morphology by a humoral pathway.

Androgens↗
PubMed2001

Immunoreactivity of iNOS in porcine uterus after infusions of Escherichia coli endotoxin.

The aim of this study was to investigate the distribution of inducible isoform of nitric oxide synthase (iNOS) in the porcine uterus after infusions of Escherichia coli endotoxin (lipopolysaccharide, LPS). In the group I (treated; n=6), 1 mg of LPS was infused into both the left and right uterine horn starting from the 4th to the 10th day of the estrous cycle, twice a day. In the group II (control; n=6), saline was infused into the uterus. The uterine horns were collected on the 14th day of the estrous cycle. Cryostat sections from the paraformaldehyde fixed tissues were stained immunohistochemically to estimate the distribution of iNOS. The luminal and glandular epithelium was stained more intensely for iNOS in the LPS-treated gilts than in the control animals. After LPS infusions, iNOS staining in vascular endothelial cells was also more intense than that observed in the controls. The present study has revealed that infusions of LPS into the porcine uterus result in an increase in the intensity of iNOS staining in some structures of this organ and supports our earlier data that NO can mediate an inflammatory effect of LPS in the uterus.

Animals↗
PubMed1996

The concentration of GnRH in hypothalamus, LH and FSH in pituitary, LH, PRL and sex steroids in peripheral and ovarian venous plasma of hypo- and hyperthyroid, cysts-bearing gilts.

The aim of this work was to investigate the hormonal pattern in hypo- and hyperthyroid gilts with experimentally induced cystic ovarian disease (COD). A total of 70 adult, nulliparous gilts divided into six groups were used for the experiment. Group I was euthyroid and control. Group II was made hypothyroid by oral administration of methylthiouracyl for 24 days. Group III represented euthyroid gilts injected with gonadotropins (PMSG and hCG). Group IV consisted of hypothyroid gilts injected with gonadotropins. Group V was treated with L-thyroxine for 24 days and Group VI with thyroxine and with gonadotropins for the last 10 days of the test. The treatment of all groups was terminated on the 4th-5th day of the next estrous cycle. The peripheral blood of the gilts was collected on Day 0, and on Day 24. On the 25th day the gilts were laparotomized and cannulas were inserted into utero-ovarian veins of each ovary for blood collection. Simultaneously, peripheral blood samples were collected during 1 to 3 consecutive days. The animals were then slaughtered and the hypothalamus, pituitary and ovaries were frozen and preserved for further analyses. In hypothalamic tissue the content of GnRH: in the pituitary the concentration of LH and FSH; and in peripheral and ovarian blood plasma the level of LH, PRL, E1, P4, A4, T and cortisol (Cl) were estimated by RIA procedure. The level of GnRH in the hypothalamus, and LH and FSH in the pituitary showed a tendency to parallel with thyroid function which may indicate a role of this gland in their production or secretion. In hypothyroid animals an increase of LH and PRL and a slight decrease of secretory function of the ovaries were noted. Injections of gonadotropins in euthyroid or hypo- and hyperthyroid gilts intensified the function of the ovaries, which was manifested by numerous follicular cysts and corpora lutea. The hormonal milieu of gilts from these groups showed a low level of LH, PRL and an increased content of sex steroids in peripheral and ovarian blood. The ovarian steroidogenesis of cyst-bearing gilts was disturbed, which was indicated by an increased level of E1, P4, A4, T, and Cl, but a low level of E2. These disturbances in steroidogenesis in cystic gilts may be caused by a deficiency in LH secretion as the consequence of the pituitary gonadotropin suppression by the used gonadotropins. The steroid hormone pattern of cyst-bearing gilts strongly resembles the endocrine profile noted in polycystic ovarian disease in women.

Animals↗